Commit Graph

3900 Commits

Author SHA1 Message Date
Ming Lei
0c6af1ccd5 blk-mq: put driver tag if dispatch budget can't be got
We have to put the driver tag if dispatch budget can't be got, otherwise
it might cause IO deadlock, especially in case that size of tags is very
small.

Fixes: de1482974080(blk-mq: introduce .get_budget and .put_budget in blk_mq_ops)
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Christoph Hellwig
f00c4d80ff block: pass full fmode_t to blk_verify_command
Use the obvious calling convention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Christoph Hellwig
d004a5e7d4 block: remove __bio_kmap_atomic
This helper doesn't buy us much over calling kmap_atomic directly.
In fact in the only caller it does a bit of useless work as the
caller already has the bvec at hand, and said caller would even
buggy for a multi-segment bio due to the use of this helper.

So just remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Jens Axboe
05b7941394 Revert "blk-mq: don't handle TAG_SHARED in restart"
This reverts commit 358a3a6bcc.

We have cases that aren't covered 100% in the drivers, so for now
we have to retain the shared tag restart loops.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-10 19:53:25 -07:00
Ingo Molnar
8c5db92a70 Merge branch 'linus' into locking/core, to resolve conflicts
Conflicts:
	include/linux/compiler-clang.h
	include/linux/compiler-gcc.h
	include/linux/compiler-intel.h
	include/uapi/linux/stddef.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 10:32:44 +01:00
Ming Lei
923218f616 blk-mq: don't allocate driver tag upfront for flush rq
The idea behind it is simple:

1) for none scheduler, driver tag has to be borrowed for flush rq,
   otherwise we may run out of tag, and that causes an IO hang. And
   get/put driver tag is actually noop for none, so reordering tags
   isn't necessary at all.

2) for a real I/O scheduler, we need not allocate a driver tag upfront
   for flush rq. It works just fine to follow the same approach as
   normal requests: allocate driver tag for each rq just before calling
   ->queue_rq().

One driver visible change is that the driver tag isn't shared in the
flush request sequence. That won't be a problem, since we always do that
in legacy path.

Then flush rq need not be treated specially wrt. get/put driver tag.
This cleans up the code - for instance, reorder_tags_to_front() can be
removed, and we needn't worry about request ordering in dispatch list
for avoiding I/O deadlock.

Also we have to put the driver tag before requeueing.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:40:13 -06:00
Ming Lei
244c65a3cc blk-mq: move blk_mq_put_driver_tag*() into blk-mq.h
We need this helper to put the driver tag for flush rq, since we will
not share tag in the flush request sequence in the following patch
in case that I/O scheduler is applied.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:39:57 -06:00
Ming Lei
a6a252e649 blk-mq-sched: decide how to handle flush rq via RQF_FLUSH_SEQ
In case of IO scheduler we always pre-allocate one driver tag before
calling blk_insert_flush(), and flush request will be marked as
RQF_FLUSH_SEQ once it is in flush machinery.

So if RQF_FLUSH_SEQ isn't set, we call blk_insert_flush() to handle
the request, otherwise the flush request is dispatched to ->dispatch
list directly.

This is a preparation patch for not preallocating a driver tag for flush
requests, and for not treating flush requests as a special case. This is
similar to what the legacy path does.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:38:50 -06:00
Ming Lei
598906f814 blk-flush: use blk_mq_request_bypass_insert()
In the following patch, we will use RQF_FLUSH_SEQ to decide:

1) if the flag isn't set, the flush rq need to be inserted via
blk_insert_flush()

2) otherwise, the flush rq need to be dispatched directly since
it is in flush machinery now.

So we use blk_mq_request_bypass_insert() for requests of bypassing
flush machinery, just like the legacy path did.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:38:40 -06:00
Ming Lei
b0850297c7 block: pass 'run_queue' to blk_mq_request_bypass_insert
Block flush need this function without running the queue, so add a
parameter controlling whether we run it or not.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:38:40 -06:00
Ming Lei
9c71c83c85 blk-flush: don't run queue for requests bypassing flush
blk_insert_flush() should only insert request since run queue always
follows it.

In case of bypassing flush, we don't need to run queue because every
blk_insert_flush() follows one run queue.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:38:40 -06:00
Jianchao Wang
6d6f167ce7 blk-mq: put the driver tag of nxt rq before first one is requeued
When freeing the driver tag of the next rq with an I/O scheduler
configured, we get the first entry of the list. However, this can
race with requeue of a request, and we end up getting the wrong request
from the head of the list. Free the driver tag of next rq before the
failed one is requeued in the failure branch of queue_rq callback.

Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:38:40 -06:00
weiping zhang
e840107322 blkcg: add sanity check for blkcg policy operations
blkcg policy should keep cpd/pd's alloc_fn and free_fn in pairs,
otherwise policy would register fail.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:31:15 -06:00
Ming Lei
88022d7201 blk-mq: don't handle failure in .get_budget
It is enough to just check if we can get the budget via .get_budget().
And we don't need to deal with device state change in .get_budget().

For SCSI, one issue to be fixed is that we have to call
scsi_mq_uninit_cmd() to free allocated ressources if SCSI device fails
to handle the request. And it isn't enough to simply call
blk_mq_end_request() to do that if this request is marked as
RQF_DONTPREP.

Fixes: 0df21c86bdbf(scsi: implement .get_budget and .put_budget for blk-mq)
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 12:31:08 -06:00
Christoph Hellwig
e4f36b249b block: fix peeking requests during PM
We need to look for an active PM request until the next softbarrier
instead of looking for the first non-PM request.  Otherwise any cause
of request reordering might starve the PM request(s).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-04 08:17:06 -06:00
Bart Van Assche
21e768b442 blk-mq: Make blk_mq_get_request() error path less confusing
blk_mq_get_tag() can modify data->ctx. This means that in the
error path of blk_mq_get_request() data->ctx should be passed to
blk_mq_put_ctx() instead of local_ctx. Note: since blk_mq_put_ctx()
ignores its argument, this patch does not change any functionality.

References: commit 1ad43c0078 ("blk-mq: don't leak preempt counter/q_usage_counter when allocating rq failed")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-03 12:33:56 -06:00
Liu Bo
39b4954c0a badblocks: fix wrong return value in badblocks_set if badblocks are disabled
MD's rdev_set_badblocks() expects that badblocks_set() returns 1 if
badblocks are disabled, otherwise, rdev_set_badblocks() will record
superblock changes and return success in that case and md will fail to
report an IO error which it should.

This bug has existed since badblocks were introduced in commit
9e0e252a04 ("badblocks: Add core badblock management code").

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Acked-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2017-11-03 11:29:50 -07:00
weiping zhang
c2e82a2348 blk-mq: fix nr_requests wrong value when modify it from sysfs
if blk-mq use "none" io scheduler, nr_request get a wrong value when
input a number > tag_set->queue_depth. blk_mq_tag_update_depth will get
the smaller one min(nr, set->queue_depth), and then q->nr_request get a
wrong value.

Reproduce:

echo none > /sys/block/nvme0n1/queue/scheduler
echo 1000000 > /sys/block/nvme0n1/queue/nr_requests
cat /sys/block/nvme0n1/queue/nr_requests
1000000

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-03 12:21:06 -06:00
Christoph Hellwig
ea435e1b93 block: add a poll_fn callback to struct request_queue
That we we can also poll non blk-mq queues.  Mostly needed for
the NVMe multipath code, but could also be useful elsewhere.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-03 10:31:48 -06:00
Christoph Hellwig
8ddcd65325 block: introduce GENHD_FL_HIDDEN
With this flag a driver can create a gendisk that can be used for I/O
submission inside the kernel, but which is not registered as user
facing block device.  This will be useful for the NVMe multipath
implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-03 10:31:48 -06:00
Christoph Hellwig
517bf3c306 block: don't look at the struct device dev_t in disk_devt
The hidden gendisks introduced in the next patch need to keep the dev
field in their struct device empty so that udev won't try to create
block device nodes for them.  To support that rewrite disk_devt to
look at the major and first_minor fields in the gendisk itself instead
of looking into the struct device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-03 10:31:48 -06:00
Christoph Hellwig
ef71de8b15 block: add a blk_steal_bios helper
This helpers allows to bounce steal the uncompleted bios from a request so
that they can be reissued on another path.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-03 10:31:48 -06:00
Christoph Hellwig
f421e1d9ad block: provide a direct_make_request helper
This helper allows reinserting a bio into a new queue without much
overhead, but requires all queue limits to be the same for the upper
and lower queues, and it does not provide any recursion preventions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Javier González <javier@cnexlabs.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-03 10:31:48 -06:00
Jens Axboe
3e2cb3ad47 Merge branch 'nvme-4.15' of git://git.infradead.org/nvme into for-4.15/block
Pull NVMe changes from Christoph:

"Below are the currently queue nvme updates for Linux 4.15.  There are
a few more things that could make it for this merge window, but I'd
like to get things into linux-next, especially for the unlikely case
that Linus decided to cut -rc8.

Highlights:
 - support for SGLs in the PCIe driver (Chaitanya Kulkarni)
 - disable I/O schedulers for the admin queue (Israel Rukshin)
 - various Fibre Channel fixes and enhancements (James Smart)
 - various refactoring for better code sharing between transports
   (Sagi Grimberg and me)

as well as lots of little bits from various contributors."
2017-11-03 10:28:51 -06:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Ming Lei
1f460b63d4 blk-mq: don't restart queue when .get_budget returns BLK_STS_RESOURCE
SCSI restarts its queue in scsi_end_request() automatically, so we don't
need to handle this case in blk-mq.

Especailly any request won't be dequeued in this case, we needn't to
worry about IO hang caused by restart vs. dispatch.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-01 08:20:34 -06:00
Ming Lei
358a3a6bcc blk-mq: don't handle TAG_SHARED in restart
Now restart is used in the following cases, and TAG_SHARED is for
SCSI only.

1) .get_budget() returns BLK_STS_RESOURCE
- if resource in target/host level isn't satisfied, this SCSI device
will be added in shost->starved_list, and the whole queue will be rerun
(via SCSI's built-in RESTART) in scsi_end_request() after any request
initiated from this host/targe is completed. Forget to mention, host level
resource can't be an issue for blk-mq at all.

- the same is true if resource in the queue level isn't satisfied.

- if there isn't outstanding request on this queue, then SCSI's RESTART
can't work(blk-mq's can't work too), and the queue will be run after
SCSI_QUEUE_DELAY, and finally all starved sdevs will be handled by SCSI's
RESTART when this request is finished

2) scsi_dispatch_cmd() returns BLK_STS_RESOURCE
- if there isn't onprogressing request on this queue, the queue
will be run after SCSI_QUEUE_DELAY

- otherwise, SCSI's RESTART covers the rerun.

3) blk_mq_get_driver_tag() failed
- BLK_MQ_S_TAG_WAITING covers the cross-queue RESTART for driver
allocation.

In one word, SCSI's built-in RESTART is enough to cover the queue
rerun, and we don't need to pay special attention to TAG_SHARED wrt. restart.

In my test on scsi_debug(8 luns), this patch improves IOPS by 20% ~ 30% when
running I/O on these 8 luns concurrently.

Aslo Roman Pen reported the current RESTART is very expensive especialy
when there are lots of LUNs attached in one host, such as in his
test, RESTART causes half of IOPS be cut.

Fixes: https://marc.info/?l=linux-kernel&m=150832216727524&w=2
Fixes: 6d8c6c0f97 ("blk-mq: Restart a single queue if tag sets are shared")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-01 08:20:33 -06:00
Ming Lei
b347689ffb blk-mq-sched: improve dispatching from sw queue
SCSI devices use host-wide tagset, and the shared driver tag space is
often quite big. However, there is also a queue depth for each lun(
.cmd_per_lun), which is often small, for example, on both lpfc and
qla2xxx, .cmd_per_lun is just 3.

So lots of requests may stay in sw queue, and we always flush all
belonging to same hw queue and dispatch them all to driver.
Unfortunately it is easy to cause queue busy because of the small
.cmd_per_lun.  Once these requests are flushed out, they have to stay in
hctx->dispatch, and no bio merge can happen on these requests, and
sequential IO performance is harmed.

This patch introduces blk_mq_dequeue_from_ctx for dequeuing a request
from a sw queue, so that we can dispatch them in scheduler's way. We can
then avoid dequeueing too many requests from sw queue, since we don't
flush ->dispatch completely.

This patch improves dispatching from sw queue by using the .get_budget
and .put_budget callbacks.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-01 08:20:02 -06:00
Ming Lei
de14829740 blk-mq: introduce .get_budget and .put_budget in blk_mq_ops
For SCSI devices, there is often a per-request-queue depth, which needs
to be respected before queuing one request.

Currently blk-mq always dequeues the request first, then calls
.queue_rq() to dispatch the request to lld. One obvious issue with this
approach is that I/O merging may not be successful, because when the
per-request-queue depth can't be respected, .queue_rq() has to return
BLK_STS_RESOURCE, and then this request has to stay in hctx->dispatch
list. This means it never gets a chance to be merged with other IO.

This patch introduces .get_budget and .put_budget callback in blk_mq_ops,
then we can try to get reserved budget first before dequeuing request.
If the budget for queueing I/O can't be satisfied, we don't need to
dequeue request at all. Hence the request can be left in the IO
scheduler queue, for more merging opportunities.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-01 08:20:02 -06:00
Ming Lei
63ba8e31c3 block: kyber: check if there are requests in ctx in kyber_has_work()
There may be request in sw queue, and not fetched to domain queue
yet, so check it in kyber_has_work().

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-01 08:20:02 -06:00
Ming Lei
caf8eb0d60 blk-mq-sched: move actual dispatching into one helper
So that it becomes easy to support to dispatch from sw queue in the
following patch.

No functional change.

Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Suggested-by: Christoph Hellwig <hch@lst.de> # for simplifying dispatch logic
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-01 08:20:02 -06:00
Ming Lei
5e3d02bbaf blk-mq-sched: dispatch from scheduler IFF progress is made in ->dispatch
When the hw queue is busy, we shouldn't take requests from the scheduler
queue any more, otherwise it is difficult to do IO merge.

This patch fixes the awful IO performance on some SCSI devices(lpfc,
qla2xxx, ...) when mq-deadline/kyber is used by not taking requests if
hw queue is busy.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-01 08:20:02 -06:00
Bart Van Assche
4e9b6f2082 block: Fix a race between blk_cleanup_queue() and timeout handling
Make sure that if the timeout timer fires after a queue has been
marked "dying" that the affected requests are finished.

Reported-by: chenxiang (M) <chenxiang66@hisilicon.com>
Fixes: commit 287922eb0b ("block: defer timeouts to a workqueue")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Tested-by: chenxiang (M) <chenxiang66@hisilicon.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-30 13:28:10 -06:00
Byungchul Park
e319e1fbd9 block, locking/lockdep: Assign a lock_class per gendisk used for wait_for_completion()
Darrick posted the following warning and Dave Chinner analyzed it:

> ======================================================
> WARNING: possible circular locking dependency detected
> 4.14.0-rc1-fixes #1 Tainted: G        W
> ------------------------------------------------------
> loop0/31693 is trying to acquire lock:
>  (&(&ip->i_mmaplock)->mr_lock){++++}, at: [<ffffffffa00f1b0c>] xfs_ilock+0x23c/0x330 [xfs]
>
> but now in release context of a crosslock acquired at the following:
>  ((complete)&ret.event){+.+.}, at: [<ffffffff81326c1f>] submit_bio_wait+0x7f/0xb0
>
> which lock already depends on the new lock.
>
> the existing dependency chain (in reverse order) is:
>
> -> #2 ((complete)&ret.event){+.+.}:
>        lock_acquire+0xab/0x200
>        wait_for_completion_io+0x4e/0x1a0
>        submit_bio_wait+0x7f/0xb0
>        blkdev_issue_zeroout+0x71/0xa0
>        xfs_bmapi_convert_unwritten+0x11f/0x1d0 [xfs]
>        xfs_bmapi_write+0x374/0x11f0 [xfs]
>        xfs_iomap_write_direct+0x2ac/0x430 [xfs]
>        xfs_file_iomap_begin+0x20d/0xd50 [xfs]
>        iomap_apply+0x43/0xe0
>        dax_iomap_rw+0x89/0xf0
>        xfs_file_dax_write+0xcc/0x220 [xfs]
>        xfs_file_write_iter+0xf0/0x130 [xfs]
>        __vfs_write+0xd9/0x150
>        vfs_write+0xc8/0x1c0
>        SyS_write+0x45/0xa0
>        entry_SYSCALL_64_fastpath+0x1f/0xbe
>
> -> #1 (&xfs_nondir_ilock_class){++++}:
>        lock_acquire+0xab/0x200
>        down_write_nested+0x4a/0xb0
>        xfs_ilock+0x263/0x330 [xfs]
>        xfs_setattr_size+0x152/0x370 [xfs]
>        xfs_vn_setattr+0x6b/0x90 [xfs]
>        notify_change+0x27d/0x3f0
>        do_truncate+0x5b/0x90
>        path_openat+0x237/0xa90
>        do_filp_open+0x8a/0xf0
>        do_sys_open+0x11c/0x1f0
>        entry_SYSCALL_64_fastpath+0x1f/0xbe
>
> -> #0 (&(&ip->i_mmaplock)->mr_lock){++++}:
>        up_write+0x1c/0x40
>        xfs_iunlock+0x1d0/0x310 [xfs]
>        xfs_file_fallocate+0x8a/0x310 [xfs]
>        loop_queue_work+0xb7/0x8d0
>        kthread_worker_fn+0xb9/0x1f0
>
> Chain exists of:
>   &(&ip->i_mmaplock)->mr_lock --> &xfs_nondir_ilock_class --> (complete)&ret.event
>
>  Possible unsafe locking scenario by crosslock:
>
>        CPU0                    CPU1
>        ----                    ----
>   lock(&xfs_nondir_ilock_class);
>   lock((complete)&ret.event);
>                                lock(&(&ip->i_mmaplock)->mr_lock);
>                                unlock((complete)&ret.event);
>
>                *** DEADLOCK ***

The warning is a false positive, caused by the fact that all
wait_for_completion()s in submit_bio_wait() are waiting with the same
lock class.

However, some bios have nothing to do with others, for example in the case
of loop devices, there's no direct connection between the bios of an upper
device and the bios of a lower device(=loop device).

The safest way to assign different lock classes to different devices is
to do it for each gendisk. In other words, this patch assigns a
lockdep_map per gendisk and uses it when initializing completion in
submit_bio_wait().

Analyzed-by: Dave Chinner <david@fromorbit.com>
Reported-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: amir73il@gmail.com
Cc: axboe@kernel.dk
Cc: david@fromorbit.com
Cc: hch@infradead.org
Cc: idryomov@gmail.com
Cc: johan@kernel.org
Cc: johannes.berg@intel.com
Cc: kernel-team@lge.com
Cc: linux-block@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-xfs@vger.kernel.org
Cc: oleg@redhat.com
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/1508921765-15396-10-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-26 07:54:17 +02:00
Jens Axboe
4d740bc9f0 mq-deadline: add 'deadline' as a name alias
The scheduler framework now supports looking up the appropriate
scheduler with the {name,mq} tupple. We can register mq-deadline
with the alias of 'deadline', so that switching to 'deadline'
will do the right thing based on the type of driver attached to
it.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-25 12:36:55 -06:00
Jens Axboe
8ac0d9a81e elevator: allow name aliases
Since we now lookup elevator types with the appropriate multiqueue
capability, allow schedulers to register with an alias alongside
the real name. This is in preparation for allowing 'mq-deadline'
to register an alias of 'deadline' as well.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-25 12:36:50 -06:00
Jens Axboe
2527d99789 elevator: lookup mq vs non-mq elevators
If an IO scheduler is selected via elevator= and it doesn't match
the driver in question wrt blk-mq support, then we fail to boot.

The elevator= parameter is deprecated and only supported for
non-mq devices. Augment the elevator lookup API so that we
pass in if we're looking for an mq capable scheduler or not,
so that we only ever return a valid type for the queue in
question.

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=196695
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-25 12:36:45 -06:00
Ilya Dryomov
d5ce4c31d6 block: cope with WRITE ZEROES failing in blkdev_issue_zeroout()
sd_config_write_same() ignores ->max_ws_blocks == 0 and resets it to
permit trying WRITE SAME on older SCSI devices, unless ->no_write_same
is set.  Because REQ_OP_WRITE_ZEROES is implemented in terms of WRITE
SAME, blkdev_issue_zeroout() may fail with -EREMOTEIO:

  $ fallocate -zn -l 1k /dev/sdg
  fallocate: fallocate failed: Remote I/O error
  $ fallocate -zn -l 1k /dev/sdg  # OK
  $ fallocate -zn -l 1k /dev/sdg  # OK

The following calls succeed because sd_done() sets ->no_write_same in
response to a sense that would become BLK_STS_TARGET/-EREMOTEIO, causing
__blkdev_issue_zeroout() to fall back to generating ZERO_PAGE bios.

This means blkdev_issue_zeroout() must cope with WRITE ZEROES failing
and fall back to manually zeroing, unless BLKDEV_ZERO_NOFALLBACK is
specified.  For BLKDEV_ZERO_NOFALLBACK case, return -EOPNOTSUPP if
sd_done() has just set ->no_write_same thus indicating lack of offload
support.

Fixes: c20cfc27a4 ("block: stop using blkdev_issue_write_same for zeroing")
Cc: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-25 12:28:23 -06:00
Ilya Dryomov
425a4dba79 block: factor out __blkdev_issue_zero_pages()
blkdev_issue_zeroout() will use this in !BLKDEV_ZERO_NOFALLBACK case.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-25 12:28:22 -06:00
Ilya Dryomov
bb749b31c2 block: move CAP_SYS_ADMIN check in blkdev_roset()
Check for CAP_SYS_ADMIN before calling into the driver, similar to
blkdev_flushbuf().  This is safer and can spare a check in the driver.

(Currently BLKROSET is overridden by md and rbd, rbd is missing the
check.  md has the check, but it covers a lot more than BLKROSET.)

Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-25 12:25:00 -06:00
Christoph Hellwig
65e53aab6d block: Use DECLARE_COMPLETION_ONSTACK() in submit_bio_wait()
Simplify the code by getting rid of the submit_bio_ret structure.

(This also helps address a lockdep false positive.)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: amir73il@gmail.com
Cc: axboe@kernel.dk
Cc: darrick.wong@oracle.com
Cc: david@fromorbit.com
Cc: hch@infradead.org
Cc: idryomov@gmail.com
Cc: johan@kernel.org
Cc: johannes.berg@intel.com
Cc: kernel-team@lge.com
Cc: linux-block@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-xfs@vger.kernel.org
Cc: oleg@redhat.com
Cc: tj@kernel.org
Link: http://lkml.kernel.org/r/1508921765-15396-2-git-send-email-byungchul.park@lge.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-25 12:18:59 +02:00
Mark Rutland
6aa7de0591 locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-25 11:01:08 +02:00
Dmitry Monakhov
351499a172 block: Invalidate cache on discard v2
It is reasonable drop page cache on discard, otherwise that pages may
be written by writeback second later, so thin provision devices will
not be happy. This seems to be a  security leak in case of secure discard case.

Also add check for queue_discard flag on early stage.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-24 18:44:57 -06:00
Sagi Grimberg
dab7487bdf block: remove blk_mq_reinit_tagset
No callers left.

Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-10-18 19:27:49 +02:00
Sagi Grimberg
149e10f8ff block: introduce blk_mq_tagset_iter
Iterator helper to apply a function on all the
tags in a given tagset. export it as it will be used
outside the block layer later on.

Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-10-18 19:27:48 +02:00
Omar Sandoval
8cf4666020 kyber: fix hang on domain token wait queue
When we're getting a domain token, if we fail to get a token on our
first attempt, we put the current hardware queue on a wait queue and
then try again just in case a token was freed after our initial attempt
but before we got on the wait queue. If this second attempt succeeds, we
currently leave the hardware queue on the wait queue. Usually this is
okay; we'll just run the hardware queue one extra time when another
token is freed. However, if the hardware queue doesn't have any other
requests waiting, then when it it gets the extra wakeup, it won't have
anything to free and therefore won't wake up any other hardware queues.
If tokens are limited, then we won't make forward progress and the
device will hang.

Reported-by: Bin Zha <zhabin.zb@alibaba-inc.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-17 16:18:11 -06:00
Randy Dunlap
519c8e9ffd block: fix Sphinx kernel-doc warning
Sphinx treats symbols that end with '_' as a kind of special
documentation indicator, so fix that by adding an ending '*'
to it.

../block/bio.c:404: ERROR: Unknown target name: "gfp".

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-16 13:00:12 -06:00
Al Viro
0e5b935d43 bio_alloc_map_data(): do bmd->iter setup right there
just need to copy it iter instead of iter->nr_segs

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:43 -04:00
Al Viro
d16d44ebb0 bio_copy_user_iov(): saner bio size calculation
it's a bounce buffer; we don't *care* how badly is the real
source/destination fragmented, all that matters is the total
size.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:42 -04:00
Al Viro
0a0f151364 bio_map_user_iov(): get rid of copying iov_iter
we do want *iter advanced

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:42 -04:00
Al Viro
98a09d6106 bio_copy_from_iter(): get rid of copying iov_iter
we want the one passed to it advanced, anyway

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:41 -04:00
Al Viro
2884d0be87 move more stuff down into bio_copy_user_iov()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:40 -04:00
Al Viro
e81cef5d30 blk_rq_map_user_iov(): move iov_iter_advance() down
... into bio_{map,copy}_user_iov()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:40 -04:00
Al Viro
b282cc7669 bio_map_user_iov(): get rid of the iov_for_each()
Use iov_iter_npages()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:39 -04:00
Al Viro
98f0bc9905 bio_map_user_iov(): move alignment check into the main loop
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:39 -04:00
Al Viro
e2e115d18b don't rely upon subsequent bio_add_pc_page() calls failing
... they might actually succeed in some cases (when we are at the
queue-imposed segments limit, the next page is not mergable with
the last one we'd got in, but the first page covered by the next
iovec *is* mergable).  Make sure that once it's failed, we are
done with that bio.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:38 -04:00
Al Viro
629e42bcc3 ... and with iov_iter_get_pages_alloc() it becomes even simpler
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:38 -04:00
Al Viro
076098e51b bio_map_user_iov(): switch to iov_iter_get_pages()/iov_iter_advance()
... and to hell with iov_for_each() nonsense

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-11 17:23:37 -04:00
Al Viro
1cfd0ddd82 bio_copy_user_iov(): don't ignore ->iov_offset
Since "block: support large requests in blk_rq_map_user_iov" we
started to call it with partially drained iter; that works fine
on the write side, but reads create a copy of iter for completion
time.  And that needs to take the possibility of ->iov_iter != 0
into account...

Cc: stable@vger.kernel.org #v4.5+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-10 23:55:14 -04:00
Al Viro
2b04e8f6bb more bio_map_user_iov() leak fixes
we need to take care of failure exit as well - pages already
in bio should be dropped by analogue of bio_unmap_pages(),
since their refcounts had been bumped only once per reference
in bio.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-10 23:54:57 -04:00
Vitaly Mayatskikh
95d78c28b5 fix unbalanced page refcounting in bio_map_user_iov
bio_map_user_iov and bio_unmap_user do unbalanced pages refcounting if
IO vector has small consecutive buffers belonging to the same page.
bio_add_pc_page merges them into one, but the page reference is never
dropped.

Cc: stable@vger.kernel.org
Signed-off-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-10-10 23:54:51 -04:00
Shaohua Li
85acb3ba2f block: set request_list for request
Legacy queue sets request's request_list, mq doesn't. This makes mq does
the same thing, so we can find cgroup of a request. Note, we really
only use blkg field of request_list, it's pointless to allocate mempool
for request_list in mq case.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-10 13:48:16 -06:00
Shaohua Li
eca8b53a67 blk-stat: delete useless code
Fix two issues:
- the per-cpu stat flush is unnecessary, nobody uses per-cpu stat except
  sum it to global stat. We can do the calculation there. The flush just
  wastes cpu time.
- some fields are signed int/s64. I don't see the point.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-10 13:48:14 -06:00
Jiufei Xue
53cfdc10a9 blk-throttle: fix null pointer dereference while throttling writeback IOs
A null pointer dereference can occur when blkcg is removed manually
with writeback IOs inflight. This is caused by the following case:

Writeback kworker submit the bio and set bio->bi_cg_private to tg
in blk_throtl_assoc_bio.
Then we remove the block cgroup manually, the blkg and tg would be
freed if there is no request inflight.
When the submitted bio come back, blk_throtl_bio_endio() fetch the tg
which was already freed.

Fix this by increasing the refcount of blkg in funcion
blk_throtl_assoc_bio() so that the blkg will not be freed until the
bio_endio called.

Reviewed-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jiufei Xue <jiufei.xjf@alibaba-inc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-10 13:09:34 -06:00
weiping zhang
58a9edce0a blkcg: check pol->cpd_free_fn before free cpd
check pol->cpd_free_fn() instead of pol->cpd_alloc_fn() when free cpd.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-10 09:04:47 -06:00
Paolo Valente
99fead8d38 block, bfq: fix unbalanced decrements of burst size
The commit "block, bfq: decrease burst size when queues in burst
exit" introduced the decrement of burst_size on the removal of a
bfq_queue from the burst list. Unfortunately, this decrement can
happen to be performed even when burst size is already equal to 0,
because of unbalanced decrements. A description follows of the cause
of these unbalanced decrements, namely a wrong assumption, and of the
way how this wrong assumption leads to unbalanced decrements.

The wrong assumption is that a bfq_queue can exit only if the process
associated with the bfq_queue has exited. This is false, because a
bfq_queue, say Q, may exit also as a consequence of a merge with
another bfq_queue. In this case, Q exits because the I/O of its
associated process has been redirected to another bfq_queue.

The decrement unbalance occurs because Q may then be re-created after
a split, and added back to the current burst list, *without*
incrementing burst_size. burst_size is not incremented because Q is
not a new bfq_queue added to the burst list, but a bfq_queue only
temporarily removed from the list, and, before the commit "bfq-sq,
bfq-mq: decrease burst size when queues in burst exit", burst_size was
not decremented when Q was removed.

This commit addresses this issue by just checking whether the exiting
bfq_queue is a merged bfq_queue, and, in that case, not decrementing
burst_size. Unfortunately, this still leaves room for unbalanced
decrements, in the following rarer case: on a split, the bfq_queue
happens to be inserted into a different burst list than that it was
removed from when merged. If this happens, the number of elements in
the new burst list becomes higher than burst_size (by one). When the
bfq_queue then exits, it is of course not in a merged state any
longer, thus burst_size is decremented, which results in an unbalanced
decrement.  To handle this sporadic, unlucky case in a simple way,
this commit also checks that burst_size is larger than 0 before
decrementing it.

Finally, this commit removes an useless, extra check: the check that
the bfq_queue is sync, performed before checking whether the bfq_queue
is in the burst list. This extra check is redundant, because only sync
bfq_queues can be inserted into the burst list.

Fixes: 7cb04004fa ("block, bfq: decrease burst size when queues in burst exit")
Reported-by: Philip Müller <philm@manjaro.org>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Angelo Ruocco <angeloruocco90@gmail.com>
Tested-by: Philip Müller <philm@manjaro.org>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-09 09:54:58 -06:00
Luca Miccio
b5dc5d4d1f block,bfq: Disable writeback throttling
Similarly to CFQ, BFQ has its write-throttling heuristics, and it
is better not to combine them with further write-throttling
heuristics of a different nature.
So this commit disables write-back throttling for a device if BFQ
is used as I/O scheduler for that device.

Signed-off-by: Luca Miccio <lucmiccio@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-09 08:29:21 -06:00
Tim Hansen
4078def82f block/bio: Remove null checks before mempool_destroy in bioset_free
This patch removes redundant checks for null values on bio_pool and
bvec_pool.

Found using make coccicheck M=block/ on linux-net tree on the
next-20170929 tag.

Signed-off-by: Tim Hansen <devtimhansen@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-06 13:03:14 -06:00
Tim Hansen
4b14a5c5d5 block: remove unnecessary NULL checks in bioset_integrity_free()
mempool_destroy() already checks for a NULL value being passed in, this
eliminates duplicate checks.

This was caught by running make coccicheck M=block/ on linus' tree on
commit 77ede3a014 (current head as of this
patch).

Reviewed-by: Kyle Fortin <kyle.fortin@oracle.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Tim Hansen <devtimhansen@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-06 13:03:12 -06:00
Christoph Hellwig
5fdee2127f block: remove QUEUE_FLAG_STACKABLE
We already have a queue_is_rq_based helper to check if a request_queue
is request based, so we can remove the flag for it.

Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-05 15:22:59 -06:00
Jens Axboe
fc13457f74 blk-mq: document the need to have STARTED and COMPLETED share a byte
For memory ordering guarantees on stores, we need to ensure that
these two bits share the same byte of storage in the unsigned
long. Add a comment as to why, and a BUILD_BUG_ON() to ensure that
we don't violate this requirement.

Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-04 11:22:24 -06:00
Peter Zijlstra
a7af0af321 blk-mq: attempt to fix atomic flag memory ordering
Attempt to untangle the ordering in blk-mq. The patch introducing the
single smp_mb__before_atomic() is obviously broken in that it doesn't
clearly specify a pairing barrier and an obtained guarantee.

The comment is further misleading in that it hints that the
deadline store and the COMPLETE store also need to be ordered, but
AFAICT there is no such dependency. However what does appear to be
important is the clear happening _after_ the store, and that worked by
pure accident.

This clarifies blk_mq_start_request() -- we should not get there with
STARTING set -- this simplifies the code and makes the barrier usage
sane (the old code could be read to allow not having _any_ atomic after
the barrier, in which case the barrier hasn't got anything to order). We
then also introduce the missing pairing barrier for it.

Also down-grade the barrier to smp_wmb(), this is cheaper for
PowerPC/ARM and doesn't cost anything extra on x86.

And it documents the STARTING vs COMPLETE ordering. Although I've not
been entirely successful in reverse engineering the blk-mq state
machine so there might still be more funnies around timeout vs
requeue.

If I got anything wrong, feel free to educate me by adding comments to
clarify things ;-)

Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Fixes: 538b753418 ("blk-mq: request deadline must be visible before marking rq as started")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-04 11:20:11 -06:00
Benjamin Block
eab40cf336 bsg-lib: fix use-after-free under memory-pressure
When under memory-pressure it is possible that the mempool which backs
the 'struct request_queue' will make use of up to BLKDEV_MIN_RQ count
emergency buffers - in case it can't get a regular allocation. These
buffers are preallocated and once they are also used, they are
re-supplied with old finished requests from the same request_queue (see
mempool_free()).

The bug is, when re-supplying the emergency pool, the old requests are
not again ran through the callback mempool_t->alloc(), and thus also not
through the callback bsg_init_rq(). Thus we skip initialization, and
while the sense-buffer still should be good, scsi_request->cmd might
have become to be an invalid pointer in the meantime. When the request
is initialized in bsg.c, and the user's CDB is larger than BLK_MAX_CDB,
bsg will replace it with a custom allocated buffer, which is freed when
the user's command is finished, thus it dangles afterwards. When next a
command is sent by the user that has a smaller/similar CDB as
BLK_MAX_CDB, bsg will assume that scsi_request->cmd is backed by
scsi_request->__cmd, will not make a custom allocation, and write into
undefined memory.

Fix this by splitting bsg_init_rq() into two functions:
 - bsg_init_rq() is changed to only do the allocation of the
   sense-buffer, which is used to back the bsg job's reply buffer. This
   pointer should never change during the lifetime of a scsi_request, so
   it doesn't need re-initialization.
 - bsg_initialize_rq() is a new function that makes use of
   'struct request_queue's initialize_rq_fn callback (which was
   introduced in v4.12). This is always called before the request is
   given out via blk_get_request(). This function does the remaining
   initialization that was previously done in bsg_init_rq(), and will
   also do it when the request is taken from the emergency-pool of the
   backing mempool.

Fixes: 50b4d48552 ("bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer")
Cc: <stable@vger.kernel.org> # 4.11+
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-04 08:35:04 -06:00
Omar Sandoval
70e62f4bac blk-mq-debugfs: fix device sched directory for default scheduler
In blk_mq_debugfs_register(), I remembered to set up the per-hctx sched
directories if a default scheduler was already configured by
blk_mq_sched_init() from blk_mq_init_allocated_queue(), but I didn't do
the same for the device-wide sched directory. Fix it.

Fixes: d332ce0918 ("blk-mq-debugfs: allow schedulers to register debugfs attributes")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 15:58:55 -06:00
Joseph Qi
4f02fb7617 blk-throttle: fix possible io stall when upgrade to max
There is a case which will lead to io stall. The case is described as
follows.
/test1
  |-subtest1
/test2
  |-subtest2
And subtest1 and subtest2 each has 32 queued bios already.

Now upgrade to max. In throtl_upgrade_state, it will try to dispatch
bios as follows:
1) tg=subtest1, do nothing;
2) tg=test1, transfer 32 queued bios from subtest1 to test1; no pending
left, no need to schedule next dispatch;
3) tg=subtest2, do nothing;
4) tg=test2, transfer 32 queued bios from subtest2 to test2; no pending
left, no need to schedule next dispatch;
5) tg=/, transfer 8 queued bios from test1 to /, 8 queued bios from
test2 to /, 8 queued bios from test1 to /, and 8 queued bios from test2
to /; note that test1 and test2 each still has 16 queued bios left;
6) tg=/, try to schedule next dispatch, but since disptime is now
(update in tg_update_disptime, wait=0), pending timer is not scheduled
in fact;
7) In throtl_upgrade_state it totally dispatches 32 queued bios and with
32 left. test1 and test2 each has 16 queued bios;
8) throtl_pending_timer_fn sees the left over bios, but could do
nothing, because throtl_select_dispatch returns 0, and test1/test2 has
no pending tg.

The blktrace shows the following:
8,32   0        0     2.539007641     0  m   N throtl upgrade to max
8,32   0        0     2.539072267     0  m   N throtl /test2 dispatch nr_queued=16 read=0 write=16
8,32   7        0     2.539077142     0  m   N throtl /test1 dispatch nr_queued=16 read=0 write=16

So force schedule dispatch if there are pending children.

Reviewed-by: Shaohua Li <shli@fb.com>
Signed-off-by: Joseph Qi <qijiang.qj@alibaba-inc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 15:41:55 -06:00
Christoph Hellwig
9c9883744d block: move __elv_next_request to blk-core.c
No need to have this helper inline in a header.  Also drop the __ prefix.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 08:43:04 -06:00
Paolo Valente
7cb04004fa block, bfq: decrease burst size when queues in burst exit
If many queues belonging to the same group happen to be created
shortly after each other, then the concurrent processes associated
with these queues have typically a common goal, and they get it done
as soon as possible if not hampered by device idling.  Examples are
processes spawned by git grep, or by systemd during boot. As for
device idling, this mechanism is currently necessary for weight
raising to succeed in its goal: privileging I/O.  In view of these
facts, BFQ does not provide the above queues with either weight
raising or device idling.

On the other hand, a burst of queue creations may be caused also by
the start-up of a complex application. In this case, these queues need
usually to be served one after the other, and as quickly as possible,
to maximise responsiveness. Therefore, in this case the best strategy
is to weight-raise all the queues created during the burst, i.e., the
exact opposite of the strategy for the above case.

To distinguish between the two cases, BFQ uses an empirical burst-size
threshold, found through extensive tests and monitoring of daily
usage. Only large bursts, i.e., burst with a size above this
threshold, are considered as generated by a high number of parallel
processes. In this respect, upstart-based boot proved to be rather
hard to detect as generating a large burst of queue creations, because
with upstart most of the queues created in a burst exit *before* the
next queues in the same burst are created. To address this issue, I
changed the burst-detection mechanism so as to not decrease the size
of the current burst even if one of the queues in the burst is
eliminated.

Unfortunately, this missing decrease causes false positives on very
fast systems: on the start-up of a complex application, such as
libreoffice writer, so many queues are created, served and exited
shortly after each other, that a large burst of queue creations is
wrongly detected as occurring. These false positives just disappear if
the size of a burst is decreased when one of the queues in the burst
exits. This commit restores the missing burst-size decrease, relying
of the fact that upstart is apparently unlikely to be used on systems
running this and future versions of the kernel.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Mauro Andreolini <mauro.andreolini@unimore.it>
Signed-off-by: Angelo Ruocco <angeloruocco90@gmail.com>
Tested-by: Mirko Montanari <mirkomontanari91@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 08:40:58 -06:00
Paolo Valente
894df937e0 block, bfq: let early-merged queues be weight-raised on split too
A just-created bfq_queue, say Q, may happen to be merged with another
bfq_queue on the very first invocation of the function
__bfq_insert_request. In such a case, even if Q would clearly deserve
interactive weight raising (as it has just been created), the function
bfq_add_request does not make it to be invoked for Q, and thus to
activate weight raising for Q. As a consequence, when the state of Q
is saved for a possible future restore, after a split of Q from the
other bfq_queue(s), such a state happens to be (unjustly)
non-weight-raised. Then the bfq_queue will not enjoy any weight
raising on the split, even if should still be in an interactive
weight-raising period when the split occurs.

This commit solves this problem as follows, for a just-created
bfq_queue that is being early-merged: it stores directly, in the saved
state of the bfq_queue, the weight-raising state that would have been
assigned to the bfq_queue if not early-merged.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Angelo Ruocco <angeloruocco90@gmail.com>
Tested-by: Mirko Montanari <mirkomontanari91@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 08:40:57 -06:00
Paolo Valente
3e2bdd6dff block, bfq: check and switch back to interactive wr also on queue split
As already explained in the message of commit "block, bfq: fix
wrong init of saved start time for weight raising", if a soft
real-time weight-raising period happens to be nested in a larger
interactive weight-raising period, then BFQ restores the interactive
weight raising at the end of the soft real-time weight raising. In
particular, BFQ checks whether the latter has ended only on request
dispatches.

Unfortunately, the above scheme fails to restore interactive weight
raising in the following corner case: if a bfq_queue, say Q,
1) Is merged with another bfq_queue while it is in a nested soft
real-time weight-raising period. The weight-raising state of Q is
then saved, and not considered any longer until a split occurs.
2) Is split from the other bfq_queue(s) at a time instant when its
soft real-time weight raising is already finished.
On the split, while resuming the previous, soft real-time
weight-raised state of the bfq_queue Q, BFQ checks whether the
current soft real-time weight-raising period is actually over. If so,
BFQ switches weight raising off for Q, *without* checking whether the
soft real-time period was actually nested in a non-yet-finished
interactive weight-raising period.

This commit addresses this issue by adding the above missing check in
bfq_queue splits, and restoring interactive weight raising if needed.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Angelo Ruocco <angeloruocco90@gmail.com>
Tested-by: Mirko Montanari <mirkomontanari91@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 08:40:56 -06:00
Paolo Valente
4baa8bb13f block, bfq: fix wrong init of saved start time for weight raising
This commit fixes a bug that causes bfq to fail to guarantee a high
responsiveness on some drives, if there is heavy random read+write I/O
in the background. More precisely, such a failure allowed this bug to
be found [1], but the bug may well cause other yet unreported
anomalies.

BFQ raises the weight of the bfq_queues associated with soft real-time
applications, to privilege the I/O, and thus reduce latency, for these
applications. This mechanism is named soft-real-time weight raising in
BFQ. A soft real-time period may happen to be nested into an
interactive weight raising period, i.e., it may happen that, when a
bfq_queue switches to a soft real-time weight-raised state, the
bfq_queue is already being weight-raised because deemed interactive
too. In this case, BFQ saves in a special variable
wr_start_at_switch_to_srt, the time instant when the interactive
weight-raising period started for the bfq_queue, i.e., the time
instant when BFQ started to deem the bfq_queue interactive. This value
is then used to check whether the interactive weight-raising period
would still be in progress when the soft real-time weight-raising
period ends.  If so, interactive weight raising is restored for the
bfq_queue. This restore is useful, in particular, because it prevents
bfq_queues from losing their interactive weight raising prematurely,
as a consequence of spurious, short-lived soft real-time
weight-raising periods caused by wrong detections as soft real-time.

If, instead, a bfq_queue switches to soft-real-time weight raising
while it *is not* already in an interactive weight-raising period,
then the variable wr_start_at_switch_to_srt has no meaning during the
following soft real-time weight-raising period. Unfortunately the
handling of this case is wrong in BFQ: not only the variable is not
flagged somehow as meaningless, but it is also set to the time when
the switch to soft real-time weight-raising occurs. This may cause an
interactive weight-raising period to be considered mistakenly as still
in progress, and thus a spurious interactive weight-raising period to
start for the bfq_queue, at the end of the soft-real-time
weight-raising period. In particular the spurious interactive
weight-raising period will be considered as still in progress, if the
soft-real-time weight-raising period does not last very long. The
bfq_queue will then be wrongly privileged and, if I/O bound, will
unjustly steal bandwidth to truly interactive or soft real-time
bfq_queues, harming responsiveness and low latency.

This commit fixes this issue by just setting wr_start_at_switch_to_srt
to minus infinity (farthest past time instant according to jiffies
macros): when the soft-real-time weight-raising period ends, certainly
no interactive weight-raising period will be considered as still in
progress.

[1] Background I/O Type: Random - Background I/O mix: Reads and writes
- Application to start: LibreOffice Writer in
http://www.phoronix.com/scan.php?page=news_item&px=Linux-4.13-IO-Laptop

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Angelo Ruocco <angeloruocco90@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Tested-by: Mirko Montanari <mirkomontanari91@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 08:40:54 -06:00
Jens Axboe
7beb2f845b blk-mq: wire up completion notifier for laptop mode
For some reason, the laptop mode IO completion notified was never wired
up for blk-mq. Ensure that we trigger the callback appropriately, to arm
the laptop mode flush timer.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-03 08:38:17 -06:00
Jens Axboe
5385fa47d8 blk-mq-tag: kill unused tag enums
We don't have any notion of a tagging cache anymore, and haven't
for a long time. Kill off the unused enums.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-10-01 01:26:21 -06:00
weiping zhang
547248736a blk-mq: remove unused function hctx_allow_merges
since 9bddeb2a5b "blk-mq: make per-sw-queue bio merge as default .bio_merge"
there is no caller for this function.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-30 02:17:37 -06:00
Shaohua Li
af551fb3be blkcg: delete unused APIs
Nobody uses the APIs right now.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-26 07:41:22 -06:00
Shaohua Li
f5c156c4c2 block: fix a crash caused by wrong API
part_stat_show takes a part device not a disk, so we should use
part_to_disk.

Fixes: d62e26b3ffd2("block: pass in queue to inflight accounting")
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-25 08:56:05 -06:00
Waiman Long
5acb3cc2c2 blktrace: Fix potential deadlock between delete & sysfs ops
The lockdep code had reported the following unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(s_active#228);
                               lock(&bdev->bd_mutex/1);
                               lock(s_active#228);
  lock(&bdev->bd_mutex);

 *** DEADLOCK ***

The deadlock may happen when one task (CPU1) is trying to delete a
partition in a block device and another task (CPU0) is accessing
tracing sysfs file (e.g. /sys/block/dm-1/trace/act_mask) in that
partition.

The s_active isn't an actual lock. It is a reference count (kn->count)
on the sysfs (kernfs) file. Removal of a sysfs file, however, require
a wait until all the references are gone. The reference count is
treated like a rwsem using lockdep instrumentation code.

The fact that a thread is in the sysfs callback method or in the
ioctl call means there is a reference to the opended sysfs or device
file. That should prevent the underlying block structure from being
removed.

Instead of using bd_mutex in the block_device structure, a new
blk_trace_mutex is now added to the request_queue structure to protect
access to the blk_trace structure.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Fix typo in patch subject line, and prune a comment detailing how
the code used to work.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-25 08:56:05 -06:00
Christoph Hellwig
f507b54dcc bsg-lib: don't free job in bsg_prepare_job
The job structure is allocated as part of the request, so we should not
free it in the error path of bsg_prepare_job.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-25 08:56:05 -06:00
Jens Axboe
157f377beb block: directly insert blk-mq request from blk_insert_cloned_request()
A NULL pointer crash was reported for the case of having the BFQ IO
scheduler attached to the underlying blk-mq paths of a DM multipath
device.  The crash occured in blk_mq_sched_insert_request()'s call to
e->type->ops.mq.insert_requests().

Paolo Valente correctly summarized why the crash occured with:
"the call chain (dm_mq_queue_rq -> map_request -> setup_clone ->
blk_rq_prep_clone) creates a cloned request without invoking
e->type->ops.mq.prepare_request for the target elevator e.  The cloned
request is therefore not initialized for the scheduler, but it is
however inserted into the scheduler by blk_mq_sched_insert_request."

All said, a request-based DM multipath device's IO scheduler should be
the only one used -- when the original requests are issued to the
underlying paths as cloned requests they are inserted directly in the
underlying dispatch queue(s) rather than through an additional elevator.

But commit bd166ef18 ("blk-mq-sched: add framework for MQ capable IO
schedulers") switched blk_insert_cloned_request() from using
blk_mq_insert_request() to blk_mq_sched_insert_request().  Which
incorrectly added elevator machinery into a call chain that isn't
supposed to have any.

To fix this introduce a blk-mq private blk_mq_request_bypass_insert()
that blk_insert_cloned_request() calls to insert the request without
involving any elevator that may be attached to the cloned request's
request_queue.

Fixes: bd166ef183 ("blk-mq-sched: add framework for MQ capable IO schedulers")
Cc: stable@vger.kernel.org
Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Tested-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-11 16:43:57 -06:00
Mikulas Patocka
09c2c359be block: fix integer overflow in __blkdev_sectors_to_bio_pages()
Fix possible integer overflow in __blkdev_sectors_to_bio_pages if
sector_t is 32-bit.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 615d22a51c ("block: Fix __blkdev_issue_zeroout loop")
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-11 09:46:49 -06:00
Scott Bauer
dbec491b12 block: sed-opal: Set MBRDone on S3 resume path if TPER is MBREnabled
Users who are booting off their Opal enabled drives are having
issues when they have a shadow MBR set up after s3/resume cycle.
When the Drive has a shadow MBR setup the MBRDone flag is set to
false upon power loss (S3/S4/S5). When the MBRDone flag is false
I/O to LBA 0 -> LBA_END_MBR are remapped to the shadow mbr
of the drive. If the drive contains useful data in the 0 -> end_mbr
range upon s3 resume the user can never get to that data as the
drive will keep remapping it to the MBR. To fix this when we unlock
on S3 resume, we need to tell the drive that we're done with the
shadow mbr (even though we didnt use it) by setting true to MBRDone.
This way the drive will stop the remapping and the user can access
their data.

Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: Scott Bauer <scott.bauer@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-11 09:45:52 -06:00
Linus Torvalds
126e76ffbf Merge branch 'for-4.14/block-postmerge' of git://git.kernel.dk/linux-block
Pull followup block layer updates from Jens Axboe:
 "I ended up splitting the main pull request for this series into two,
  mainly because of clashes between NVMe fixes that went into 4.13 after
  the for-4.14 branches were split off. This pull request is mostly
  NVMe, but not exclusively. In detail, it contains:

   - Two pull request for NVMe changes from Christoph. Nothing new on
     the feature front, basically just fixes all over the map for the
     core bits, transport, rdma, etc.

   - Series from Bart, cleaning up various bits in the BFQ scheduler.

   - Series of bcache fixes, which has been lingering for a release or
     two. Coly sent this in, but patches from various people in this
     area.

   - Set of patches for BFQ from Paolo himself, updating both
     documentation and fixing some corner cases in performance.

   - Series from Omar, attempting to now get the 4k loop support
     correct. Our confidence level is higher this time.

   - Series from Shaohua for loop as well, improving O_DIRECT
     performance and fixing a use-after-free"

* 'for-4.14/block-postmerge' of git://git.kernel.dk/linux-block: (74 commits)
  bcache: initialize dirty stripes in flash_dev_run()
  loop: set physical block size to logical block size
  bcache: fix bch_hprint crash and improve output
  bcache: Update continue_at() documentation
  bcache: silence static checker warning
  bcache: fix for gc and write-back race
  bcache: increase the number of open buckets
  bcache: Correct return value for sysfs attach errors
  bcache: correct cache_dirty_target in __update_writeback_rate()
  bcache: gc does not work when triggering by manual command
  bcache: Don't reinvent the wheel but use existing llist API
  bcache: do not subtract sectors_to_gc for bypassed IO
  bcache: fix sequential large write IO bypass
  bcache: Fix leak of bdev reference
  block/loop: remove unused field
  block/loop: fix use after free
  bfq: Use icq_to_bic() consistently
  bfq: Suppress compiler warnings about comparisons
  bfq: Check kstrtoul() return value
  bfq: Declare local functions static
  ...
2017-09-09 12:49:01 -07:00
Davidlohr Bueso
f0f1a45f95 block/cfq: cache rightmost rb_node
For the same reasons we already cache the leftmost pointer, apply the same
optimization for rb_last() calls.  Users must explicitly do this as
rb_root_cached only deals with the smallest node.

[dave@stgolabs.net: brain fart #1]
  Link: http://lkml.kernel.org/r/20170731155955.GD21328@linux-80c1.suse
Link: http://lkml.kernel.org/r/20170719014603.19029-18-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:49 -07:00
Davidlohr Bueso
09663c86e2 block/cfq: replace cfq_rb_root leftmost caching
... with the generic rbtree flavor instead. No changes
in semantics whatsoever.

Link: http://lkml.kernel.org/r/20170719014603.19029-11-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:49 -07:00
Linus Torvalds
572c01ba19 SCSI misc on 20170907
This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas, megaraid_sas, zfcp and a host of minor updates.
 
 The major driver change here is the elimination of the block based
 cciss driver in favour of the SCSI based hpsa driver (which now drives
 all the legacy cases cciss used to be required for).  Plus a reset
 handler clean up and the redo of the SAS SMP handler to use bsg lib.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQIcBAABAgAGBQJZscDNAAoJEAVr7HOZEZN4DWIQAK/UkkrvKpV/jLATM/yi7CoL
 QidY86Hmwwl7A9HQ+2fjLfAsye0xcCzRwkucKK90IP5b4pefHhiJJfiMKAAe3TUW
 xstnY5z5jaOhDG4nyJFoSm5fH5qXkMnJ8NZRK8f6Qg5yBN5dStEKqoBboNsz4KBI
 md7idw0mbp5i2GXlJwSpc5eDS97GiPL6WkwgGaGKfXF1NDau0GbEdjijfz55haCD
 pMhY7WJh/71RfOq/1ThXT1Z3khOlVcKXrkdO+602n7zh/klRBRtBC8m2a6xCfZPj
 n7Pb/s0jhCQPd+e/Xtv7WEbY8uNOCrGoVgZ6U5EGrT5IeTfep24ackYqerjMhE63
 esi4BJY8lUP9SGleLMgjYWyCHdmxBJRa7UI614DWN/H0QoGP6j/2EzGoi5Fw04vC
 H8/+aqPPWZc9KUBioRYo8xWO8YgMqL2eyXY+Tc9cwxqAe2T6k/NC1zJVgDFKXfzb
 QoWW4v9NNmYwf5vL/7tNgkeTMFQV66yUR7dR3SGTSk8UIrJ40ok0JyUAsDg86ZAH
 BfMkWwhWQ6Byoel0Y7Ti88T49Cox/64r/I0ux06Qgg99+KpRLT7z20+GLIEHgXxg
 116C39rgvYKqzc7W8RCyj8qSROuMVzg6QFbB6n+1PEsYIX2O8A2Re3jdS34q2LbX
 aBDm/Lfdl4kkJrV9xY6P
 =nQUG
 -----END PGP SIGNATURE-----

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas,
  megaraid_sas, zfcp and a host of minor updates.

  The major driver change here is the elimination of the block based
  cciss driver in favour of the SCSI based hpsa driver (which now drives
  all the legacy cases cciss used to be required for). Plus a reset
  handler clean up and the redo of the SAS SMP handler to use bsg lib"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (279 commits)
  scsi: scsi-mq: Always unprepare before requeuing a request
  scsi: Show .retries and .jiffies_at_alloc in debugfs
  scsi: Improve requeuing behavior
  scsi: Call scsi_initialize_rq() for filesystem requests
  scsi: qla2xxx: Reset the logo flag, after target re-login.
  scsi: qla2xxx: Fix slow mem alloc behind lock
  scsi: qla2xxx: Clear fc4f_nvme flag
  scsi: qla2xxx: add missing includes for qla_isr
  scsi: qla2xxx: Fix an integer overflow in sysfs code
  scsi: aacraid: report -ENOMEM to upper layer from aac_convert_sgraw2()
  scsi: aacraid: get rid of one level of indentation
  scsi: aacraid: fix indentation errors
  scsi: storvsc: fix memory leak on ring buffer busy
  scsi: scsi_transport_sas: switch to bsg-lib for SMP passthrough
  scsi: smartpqi: remove the smp_handler stub
  scsi: hpsa: remove the smp_handler stub
  scsi: bsg-lib: pass the release callback through bsg_setup_queue
  scsi: Rework handling of scsi_device.vpd_pg8[03]
  scsi: Rework the code for caching Vital Product Data (VPD)
  scsi: rcu: Introduce rcu_swap_protected()
  ...
2017-09-07 21:11:05 -07:00
Linus Torvalds
3645e6d0dc Merge tag 'md/4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md
Pull MD updates from Shaohua Li:
 "This update mainly fixes bugs:

   - Make raid5 ppl support several ppl from Pawel

   - Several raid5-cache bug fixes from Song

   - Bitmap fixes from Neil and Me

   - One raid1/10 regression fix since 4.12 from Me

   - Other small fixes and cleanup"

* tag 'md/4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md/bitmap: disable bitmap_resize for file-backed bitmaps.
  raid5-ppl: Recovery support for multiple partial parity logs
  md: Runtime support for multiple ppls
  md/raid0: attach correct cgroup info in bio
  lib/raid6: align AVX512 constants to 512 bits, not bytes
  raid5: remove raid5_build_block
  md/r5cache: call mddev_lock/unlock() in r5c_journal_mode_show
  md: replace seq_release_private with seq_release
  md: notify about new spare disk in the container
  md/raid1/10: reset bio allocated from mempool
  md/raid5: release/flush io in raid5_do_work()
  md/bitmap: copy correct data for bitmap super
2017-09-07 12:41:48 -07:00
Linus Torvalds
a0725ab0c7 Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
 "This is the first pull request for 4.14, containing most of the code
  changes. It's a quiet series this round, which I think we needed after
  the churn of the last few series. This contains:

   - Fix for a registration race in loop, from Anton Volkov.

   - Overflow complaint fix from Arnd for DAC960.

   - Series of drbd changes from the usual suspects.

   - Conversion of the stec/skd driver to blk-mq. From Bart.

   - A few BFQ improvements/fixes from Paolo.

   - CFQ improvement from Ritesh, allowing idling for group idle.

   - A few fixes found by Dan's smatch, courtesy of Dan.

   - A warning fixup for a race between changing the IO scheduler and
     device remova. From David Jeffery.

   - A few nbd fixes from Josef.

   - Support for cgroup info in blktrace, from Shaohua.

   - Also from Shaohua, new features in the null_blk driver to allow it
     to actually hold data, among other things.

   - Various corner cases and error handling fixes from Weiping Zhang.

   - Improvements to the IO stats tracking for blk-mq from me. Can
     drastically improve performance for fast devices and/or big
     machines.

   - Series from Christoph removing bi_bdev as being needed for IO
     submission, in preparation for nvme multipathing code.

   - Series from Bart, including various cleanups and fixes for switch
     fall through case complaints"

* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
  kernfs: checking for IS_ERR() instead of NULL
  drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
  drbd: Fix allyesconfig build, fix recent commit
  drbd: switch from kmalloc() to kmalloc_array()
  drbd: abort drbd_start_resync if there is no connection
  drbd: move global variables to drbd namespace and make some static
  drbd: rename "usermode_helper" to "drbd_usermode_helper"
  drbd: fix race between handshake and admin disconnect/down
  drbd: fix potential deadlock when trying to detach during handshake
  drbd: A single dot should be put into a sequence.
  drbd: fix rmmod cleanup, remove _all_ debugfs entries
  drbd: Use setup_timer() instead of init_timer() to simplify the code.
  drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
  drbd: new disk-option disable-write-same
  drbd: Fix resource role for newly created resources in events2
  drbd: mark symbols static where possible
  drbd: Send P_NEG_ACK upon write error in protocol != C
  drbd: add explicit plugging when submitting batches
  drbd: change list_for_each_safe to while(list_first_entry_or_null)
  drbd: introduce drbd_recv_header_maybe_unplug
  ...
2017-09-07 11:59:42 -07:00
Linus Torvalds
bafb0762cb Char/Misc drivers for 4.14-rc1
Here is the big char/misc driver update for 4.14-rc1.
 
 Lots of different stuff in here, it's been an active development cycle
 for some reason.  Highlights are:
   - updated binder driver, this brings binder up to date with what
     shipped in the Android O release, plus some more changes that
     happened since then that are in the Android development trees.
   - coresight updates and fixes
   - mux driver file renames to be a bit "nicer"
   - intel_th driver updates
   - normal set of hyper-v updates and changes
   - small fpga subsystem and driver updates
   - lots of const code changes all over the driver trees
   - extcon driver updates
   - fmc driver subsystem upadates
   - w1 subsystem minor reworks and new features and drivers added
   - spmi driver updates
 
 Plus a smattering of other minor driver updates and fixes.
 
 All of these have been in linux-next with no reported issues for a
 while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 -----BEGIN PGP SIGNATURE-----
 
 iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCWa1+Ew8cZ3JlZ0Brcm9h
 aC5jb20ACgkQMUfUDdst+yl26wCgquufNylfhxr65NbJrovduJYzRnUAniCivXg8
 bePIh/JI5WxWoHK+wEbY
 =hYWx
 -----END PGP SIGNATURE-----

Merge tag 'char-misc-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big char/misc driver update for 4.14-rc1.

  Lots of different stuff in here, it's been an active development cycle
  for some reason. Highlights are:

   - updated binder driver, this brings binder up to date with what
     shipped in the Android O release, plus some more changes that
     happened since then that are in the Android development trees.

   - coresight updates and fixes

   - mux driver file renames to be a bit "nicer"

   - intel_th driver updates

   - normal set of hyper-v updates and changes

   - small fpga subsystem and driver updates

   - lots of const code changes all over the driver trees

   - extcon driver updates

   - fmc driver subsystem upadates

   - w1 subsystem minor reworks and new features and drivers added

   - spmi driver updates

  Plus a smattering of other minor driver updates and fixes.

  All of these have been in linux-next with no reported issues for a
  while"

* tag 'char-misc-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (244 commits)
  ANDROID: binder: don't queue async transactions to thread.
  ANDROID: binder: don't enqueue death notifications to thread todo.
  ANDROID: binder: Don't BUG_ON(!spin_is_locked()).
  ANDROID: binder: Add BINDER_GET_NODE_DEBUG_INFO ioctl
  ANDROID: binder: push new transactions to waiting threads.
  ANDROID: binder: remove proc waitqueue
  android: binder: Add page usage in binder stats
  android: binder: fixup crash introduced by moving buffer hdr
  drivers: w1: add hwmon temp support for w1_therm
  drivers: w1: refactor w1_slave_show to make the temp reading functionality separate
  drivers: w1: add hwmon support structures
  eeprom: idt_89hpesx: Support both ACPI and OF probing
  mcb: Fix an error handling path in 'chameleon_parse_cells()'
  MCB: add support for SC31 to mcb-lpc
  mux: make device_type const
  char: virtio: constify attribute_group structures.
  Documentation/ABI: document the nvmem sysfs files
  lkdtm: fix spelling mistake: "incremeted" -> "incremented"
  perf: cs-etm: Fix ETMv4 CONFIGR entry in perf.data file
  nvmem: include linux/err.h from header
  ...
2017-09-05 11:08:17 -07:00
Ingo Molnar
edc2988c54 Merge branch 'linus' into locking/core, to fix up conflicts
Conflicts:
	mm/page_alloc.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-04 11:01:18 +02:00
Linus Torvalds
aa9d4648c2 Updates for 4.14 kernel merge window
- Lots of hfi1 driver updates (mixed with a few qib and core updates as
   well)
 - rxe updates
 - various mlx updates
 - Set default roce type to RoCEv2
 - Several larger fixes for bnxt_re that were too big for -rc
 - Several larger fixes for qedr that, likewise, were too big for -rc
 - Misc core changes
 - Make the hns_roce driver compilable on arches other than aarch64 so we
   can more easily debug build issues related to it
 - Add rdma-netlink infrastructure updates
 - Add automatic IRQ affinity infrastructure
 - Add 32bit lid support
 - Lots of misc fixes across the subsystem from random people
 - Autoloading of RDMA netlink modules
 - PCI pool cleanups from Romain Perier
 - mlx5 driver feature additions and fixes
 - Hardware tag matchine feature
 - Fix sleeping in atomic when resolving roce ah
 - Add experimental ioctl interface as posted to linux-api@
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZqBDtAAoJELgmozMOVy/dNlcQAJhYNRGaNUBx0L6+8t2xwUrt
 7ndP6qlMar30DJY9FjTQCzRBw0CRMWkXdJD8rYlyaHy07pjWDKG8LZtxEXu1FLdZ
 oNRvQX6ZJh8Bz7db2SQFBCTF2uWGZZFqWQCrSbQwjj9xxjMDs59u/knmwHVY9dKk
 egjPG4IQBDmcTeNY7h1otG2hXpx7QPIOilQW2EFN5SWAuBAazdF2JKxjjxqhnUfp
 gD2pSdgsm3VSMoo0zpMa6qOP+9GcOu8J97fYFhasRYWCavPdWHyq+XNu9S/eicRd
 xbv+seCYM+9jPb2dsNdjEKll7w3yyWdu7h6tSCMPYv54eN9sDDiO1w2L2ZnESMZa
 JRnSfB+HXru1r4RyHOTPO8peaNhYlR1V4u8bTS5G2dffbHis9BajkWoAR/oSiUcB
 AIjIIDcdJFVGfpF9KIt/pEl+adHNgESibSijzOUYkyw6RNbPqDmdd7YakPHcQhKN
 clE3zQfIsPRLWsToP/nkBE0tUd3tQocRuLy7ote7hXQK+0p7TBz0a6Kkj87MvX33
 8dVbUI+q6WRlEY90l71y0ZdXy/AvkxkFxAc4Y7FQZyJxhEArTaKgfa5fmpRwVxBm
 yi9baoYCspHNRNv6AO4IL86ZCJqmWBuch8CBY1n2X3h8IGfKYEZUAZ+T/mnTTeUq
 A4joXduz94ZD4w23leD1
 =2ntC
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma

Pull rdma updates from Doug Ledford:
 "This is a big pull request.

  Of note is that I'm sending you the new ioctl API for the rdma
  subsystem. We put it up on linux-api@, but didn't get much response.
  The API is complex, but it solves two different problems in one go:

   1) The bi-directional nature of the RDMA file write calls, which
      created the security hole we had to handle (and for which the fix
      is now causing problems for systems in production, we were a bit
      over zealous in the fix and the ability to open a device, then
      fork, then create new queue pairs on the device and use them is
      broken).

   2) The bloat caused by different vendors implementing extensions to
      the base verbs API. Each vendor's hardware is slightly different,
      and the hardware might be suitable for one extension but not
      another.

      By the time we add generic extensions for all the different ways
      that the different hardware can offload things, the API becomes
      bloated. Things like our completion structs have started to exceed
      a cache line in size because of all the elements needed to support
      this. That in turn shows up heavily in the performance graphs with
      a noticable drop in performance on 100Gigabit links as our
      completion structs go from occupying one cache line to 1+.

      This API makes things like the completion structs modular in a
      very similar way to netlink so that your structs can only include
      the items needed for the offloads/features you are actually using
      on a given queue pair. In that way we support everything, but only
      use what we need, and our structs stay smaller.

  The ioctl API is better explained by the posting on linux-api@ than I
  can explain it here, so I'll just leave it at that.

  The rest of the pull request is typical stuff.

  Updates for 4.14 kernel merge window

   - Lots of hfi1 driver updates (mixed with a few qib and core updates
     as well)

   - rxe updates

   - various mlx updates

   - Set default roce type to RoCEv2

   - Several larger fixes for bnxt_re that were too big for -rc

   - Several larger fixes for qedr that, likewise, were too big for -rc

   - Misc core changes

   - Make the hns_roce driver compilable on arches other than aarch64 so
     we can more easily debug build issues related to it

   - Add rdma-netlink infrastructure updates

   - Add automatic IRQ affinity infrastructure

   - Add 32bit lid support

   - Lots of misc fixes across the subsystem from random people

   - Autoloading of RDMA netlink modules

   - PCI pool cleanups from Romain Perier

   - mlx5 driver feature additions and fixes

   - Hardware tag matchine feature

   - Fix sleeping in atomic when resolving roce ah

   - Add experimental ioctl interface as posted to linux-api@"

* tag 'for-linus-ioctl' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (328 commits)
  IB/core: Expose ioctl interface through experimental Kconfig
  IB/core: Assign root to all drivers
  IB/core: Add completion queue (cq) object actions
  IB/core: Add legacy driver's user-data
  IB/core: Export ioctl enum types to user-space
  IB/core: Explicitly destroy an object while keeping uobject
  IB/core: Add macros for declaring methods and attributes
  IB/core: Add uverbs merge trees functionality
  IB/core: Add DEVICE object and root tree structure
  IB/core: Declare an object instead of declaring only type attributes
  IB/core: Add new ioctl interface
  RDMA/vmw_pvrdma: Fix a signedness
  RDMA/vmw_pvrdma: Report network header type in WC
  IB/core: Add might_sleep() annotation to ib_init_ah_from_wc()
  IB/cm: Fix sleeping in atomic when RoCE is used
  IB/core: Add support to finalize objects in one transaction
  IB/core: Add a generic way to execute an operation on a uobject
  Documentation: Hardware tag matching
  IB/mlx5: Support IB_SRQT_TM
  net/mlx5: Add XRQ support
  ...
2017-09-03 17:49:17 -07:00
Bart Van Assche
12cd3a2fe3 bfq: Use icq_to_bic() consistently
Some code uses icq_to_bic() to convert an io_cq pointer to a
bfq_io_cq pointer while other code uses a direct cast. Convert
the code that uses a direct cast such that it uses icq_to_bic().

Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 13:56:42 -06:00
Bart Van Assche
1530486cda bfq: Suppress compiler warnings about comparisons
This patch avoids that the following warnings are reported when
building with W=1:

block/bfq-iosched.c: In function 'bfq_back_seek_max_store':
block/bfq-iosched.c:4860:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/bfq-iosched.c:4876:1: note: in expansion of macro 'STORE_FUNCTION'
 STORE_FUNCTION(bfq_back_seek_max_store, &bfqd->bfq_back_max, 0, INT_MAX, 0);
 ^~~~~~~~~~~~~~
block/bfq-iosched.c: In function 'bfq_slice_idle_store':
block/bfq-iosched.c:4860:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/bfq-iosched.c:4879:1: note: in expansion of macro 'STORE_FUNCTION'
 STORE_FUNCTION(bfq_slice_idle_store, &bfqd->bfq_slice_idle, 0, INT_MAX, 2);
 ^~~~~~~~~~~~~~
block/bfq-iosched.c: In function 'bfq_slice_idle_us_store':
block/bfq-iosched.c:4892:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
  if (__data < (MIN))      \
             ^
block/bfq-iosched.c:4899:1: note: in expansion of macro 'USEC_STORE_FUNCTION'
 USEC_STORE_FUNCTION(bfq_slice_idle_us_store, &bfqd->bfq_slice_idle, 0,
 ^~~~~~~~~~~~~~~~~~~

Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 13:56:40 -06:00
Bart Van Assche
2f79136ba2 bfq: Check kstrtoul() return value
Make sysfs writes fail for invalid numbers instead of storing
uninitialized data copied from the stack. This patch removes
all uninitialized_var() occurrences from the BFQ source code.

Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 13:56:39 -06:00
Bart Van Assche
dfb79af546 bfq: Declare local functions static
Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 13:56:37 -06:00
Bart Van Assche
fa393d1b9c bfq: Annotate fall-through in a switch statement
This patch avoids that gcc 7 issues a warning about fall-through
when building with W=1.

Acked-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 13:56:36 -06:00
Bart Van Assche
8363dae234 compat_hdio_ioctl: Fix a declaration
This patch avoids that sparse reports the following warning messages:

block/compat_ioctl.c:85:11: warning: incorrect type in assignment (different address spaces)
block/compat_ioctl.c:85:11:    expected unsigned long *[noderef] <asn:1>p
block/compat_ioctl.c:85:11:    got void [noderef] <asn:1>*
block/compat_ioctl.c:91:21: warning: incorrect type in argument 1 (different address spaces)
block/compat_ioctl.c:91:21:    expected void const volatile [noderef] <asn:1>*<noident>
block/compat_ioctl.c:91:21:    got unsigned long *[noderef] <asn:1>p
block/compat_ioctl.c:87:53: warning: dereference of noderef expression
block/compat_ioctl.c:91:21: warning: dereference of noderef expression

Fixes: commit d597580d37 ("generic ...copy_..._user primitives")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-08-31 17:32:41 -04:00
Paolo Valente
24d90bb2f3 block, bfq: guarantee update_next_in_service always returns an eligible entity
If the function bfq_update_next_in_service is invoked as a consequence
of the activation or requeueing of an entity, say E, then it doesn't
invoke bfq_lookup_next_entity to get the next-in-service entity. In
contrast, it follows a shorter path: if E happens to be eligible (see
commit "bfq-sq-mq: make lookup_next_entity push up vtime on
expirations" for details on eligibility) and to have a lower virtual
finish time than the current candidate as next-in-service entity, then
E directly becomes the next-in-service entity. Unfortunately, there is
a corner case for which this shorter path makes
bfq_update_next_in_service choose a non eligible entity: it occurs if
both E and the current next-in-service entity happen to be non
eligible when bfq_update_next_in_service is invoked. In this case, E
is not set as next-in-service, and, since bfq_lookup_next_entity is
not invoked, the state of the parent entity is not updated so as to
end up with an eligible entity as the proper next-in-service entity.

In this respect, next-in-service is actually allowed to be non
eligible while some queue is in service: since no system-virtual-time
push-up can be performed in that case (see again commit "bfq-sq-mq:
make lookup_next_entity push up vtime on expirations" for details),
next-in-service is chosen, speculatively, as a function of the
possible value that the system virtual time may get after a push
up. But the correctness of the schedule breaks if next-in-service is
still a non eligible entity when it is time to set in service the next
entity. Unfortunately, this may happen in the above corner case.

This commit fixes this problem by making bfq_update_next_in_service
invoke bfq_lookup_next_entity not only if the above shorter path
cannot be taken, but also if the shorter path is taken but fails to
yield an eligible next-in-service entity.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-31 08:20:31 -06:00
Paolo Valente
a02195ce86 block, bfq: remove direct switch to an entity in higher class
If the function bfq_update_next_in_service is invoked as a consequence
of the activation or requeueing of an entity, say E, and finds out
that E belongs to a higher-priority class than that of the current
next-in-service entity, then it sets next_in_service directly to
E. But this may lead to anomalous schedules, because E may happen not
be eligible for service, because its virtual start time is higher than
the system virtual time for its service tree.

This commit addresses this issue by simply removing this direct
switch.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-31 08:20:29 -06:00
Paolo Valente
80294c3bbf block, bfq: make lookup_next_entity push up vtime on expirations
To provide a very smooth service, bfq starts to serve a bfq_queue
only if the queue is 'eligible', i.e., if the same queue would
have started to be served in the ideal, perfectly fair system that
bfq simulates internally. This is obtained by associating each
queue with a virtual start time, and by computing a special system
virtual time quantity: a queue is eligible only if the system
virtual time has reached the virtual start time of the
queue. Finally, bfq guarantees that, when a new queue must be set
in service, there is always at least one eligible entity for each
active parent entity in the scheduler. To provide this guarantee,
the function __bfq_lookup_next_entity pushes up, for each parent
entity on which it is invoked, the system virtual time to the
minimum among the virtual start times of the entities in the
active tree for the parent entity (more precisely, the push up
occurs if the system virtual time happens to be lower than all
such virtual start times).

There is however a circumstance in which __bfq_lookup_next_entity
cannot push up the system virtual time for a parent entity, even
if the system virtual time is lower than the virtual start times
of all the child entities in the active tree. It happens if one of
the child entities is in service. In fact, in such a case, there
is already an eligible entity, the in-service one, even if it may
not be not present in the active tree (because in-service entities
may be removed from the active tree).

Unfortunately, in the last re-design of the
hierarchical-scheduling engine, the reset of the pointer to the
in-service entity for a given parent entity--reset to be done as a
consequence of the expiration of the in-service entity--always
happens after the function __bfq_lookup_next_entity has been
invoked. This causes the function to think that there is still an
entity in service for the parent entity, and then that the system
virtual time cannot be pushed up, even if actually such a
no-more-in-service entity has already been properly reinserted
into the active tree (or in some other tree if no more
active). Yet, the system virtual time *had* to be pushed up, to be
ready to correctly choose the next queue to serve. Because of the
lack of this push up, bfq may wrongly set in service a queue that
had been speculatively pre-computed as the possible
next-in-service queue, but that would no more be the one to serve
after the expiration and the reinsertion into the active trees of
the previously in-service entities.

This commit addresses this issue by making
__bfq_lookup_next_entity properly push up the system virtual time
if an expiration is occurring.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-31 08:20:28 -06:00
Christoph Hellwig
c1225f01af scsi: bsg-lib: pass the release callback through bsg_setup_queue
The SAS code will need it.  Also mark the name argument const to match
bsg_register_queue.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-29 21:51:43 -04:00
Christoph Hellwig
c529594f93 bsg: remove #if 0'ed code
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 10:50:30 -06:00
Ben Hutchings
7de967e76f mq-deadline: Enable auto-loading when built as module
The block core requests modules with the "-iosched" name suffix, but
mq-deadline does not have that suffix.  Add an alias.

Fixes: 945ffb60c1 ("mq-deadline: add blk-mq adaptation of the deadline ...")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 10:47:23 -06:00
Ben Hutchings
26b4cf2497 bfq: Re-enable auto-loading when built as a module
The block core requests modules with the "-iosched" name suffix, but
bfq no longer has that suffix.  Add an alias.

Fixes: ea25da4808 ("block, bfq: split bfq-iosched.c into multiple ...")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 10:47:23 -06:00
Damien Le Moal
5034435c84 block: Make blk_dequeue_request() static
The only caller of this function is blk_start_request() in the same
file. Fix blk_start_request() description accordingly.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 09:49:31 -06:00
Ying Huang
966a967116 smp: Avoid using two cache lines for struct call_single_data
struct call_single_data is used in IPIs to transfer information between
CPUs.  Its size is bigger than sizeof(unsigned long) and less than
cache line size.  Currently it is not allocated with any explicit alignment
requirements.  This makes it possible for allocated call_single_data to
cross two cache lines, which results in double the number of the cache lines
that need to be transferred among CPUs.

This can be fixed by requiring call_single_data to be aligned with the
size of call_single_data. Currently the size of call_single_data is the
power of 2.  If we add new fields to call_single_data, we may need to
add padding to make sure the size of new definition is the power of 2
as well.

Fortunately, this is enforced by GCC, which will report bad sizes.

To set alignment requirements of call_single_data to the size of
call_single_data, a struct definition and a typedef is used.

To test the effect of the patch, I used the vm-scalability multiple
thread swap test case (swap-w-seq-mt).  The test will create multiple
threads and each thread will eat memory until all RAM and part of swap
is used, so that huge number of IPIs are triggered when unmapping
memory.  In the test, the throughput of memory writing improves ~5%
compared with misaligned call_single_data, because of faster IPIs.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Huang, Ying <ying.huang@intel.com>
[ Add call_single_data_t and align with size of call_single_data. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/87bmnqd6lz.fsf@yhuang-mobile.sh.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 15:14:38 +02:00
Jens Axboe
cd996fb47c Linux 4.13-rc7
-----BEGIN PGP SIGNATURE-----
 
 iQEcBAABAgAGBQJZo2HiAAoJEHm+PkMAQRiG3OcIAJqSeVK2uQ/QhmqFN1ExYay4
 bdTjSTtSk7GH6PxI2C0cqfZvsxOUU7ICDHG8bYM1LA0S0SxfOtoFhHGKc/BcFLX8
 MiKJWlF51ZbX0mkIEpKF+C8pRrXPgSqtk3N450/k2BzG9qCZSM93A2NCOB7v9T9w
 XOBUIYHqfTS2tdmCinjwu8Ls+w8oPOGH1gLjxZyGnBlg4lTqHMcUufmHeVEAh11d
 giGByqqqXH69kGD1HNC7H6quzXN9rz4n0gEwEG0mIhfkJ98b+ESSWwSEXXypOAQD
 QT5/6+2YizXf5DPCqR46xasQCPjRsS6Sv0cF2cntW2PEAb4jBjhx5gTFlJcoOC8=
 =efWJ
 -----END PGP SIGNATURE-----

Merge tag 'v4.13-rc7' into for-4.14/block-postmerge

Linux 4.13-rc7

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 13:00:44 -06:00
David Jeffery
e9a823fb34 block: fix warning when I/O elevator is changed as request_queue is being removed
There is a race between changing I/O elevator and request_queue removal
which can trigger the warning in kobject_add_internal.  A program can
use sysfs to request a change of elevator at the same time another task
is unregistering the request_queue the elevator would be attached to.
The elevator's kobject will then attempt to be connected to the
request_queue in the object tree when the request_queue has just been
removed from sysfs.  This triggers the warning in kobject_add_internal
as the request_queue no longer has a sysfs directory:

kobject_add_internal failed for iosched (error: -2 parent: queue)
------------[ cut here ]------------
WARNING: CPU: 3 PID: 14075 at lib/kobject.c:244 kobject_add_internal+0x103/0x2d0

To fix this warning, we can check the QUEUE_FLAG_REGISTERED flag when
changing the elevator and use the request_queue's sysfs_lock to
serialize between clearing the flag and the elevator testing the flag.

Signed-off-by: David Jeffery <djeffery@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 10:52:44 -06:00
weiping zhang
235f8da119 block, scheduler: convert xxx_var_store to void
The last parameter "count" never be used in xxx_var_store,
convert these functions to void.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 10:01:08 -06:00
Greg Kroah-Hartman
9749c37275 Merge 4.13-rc7 into char-misc-next
We want the binder fix in here as well for testing and merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28 10:19:01 +02:00
weiping zhang
4c18c9e962 blkcg: avoid free blkcg_root when failed to alloc blkcg policy
this patch fix two errors, firstly avoid kfree blk_root, secondly not
free(blkcg) ,if blkcg alloc fail(blkcg == NULL), just unlock that mutex;

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 13:51:07 -06:00
Shaohua Li
8a8e6f84ad md/raid0: attach correct cgroup info in bio
The discard bio doesn't attach the original bio cgroup info. Normal bio
is cloned, so is fine.

Signed-off-by: Shaohua Li <shli@fb.com>
2017-08-25 10:21:48 -07:00
Omar Sandoval
3140c3cfae block: update comments to reflect REQ_FLUSH -> REQ_PREFLUSH rename
Normally I wouldn't bother with this, but in my opinion the comments are
the most important part of this whole file since without them no one
would have any clue how this insanity works.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 10:36:54 -06:00
Bart Van Assche
22d538213e blk-mq-debugfs: Add names for recently added flags
The symbolic constants QUEUE_FLAG_SCSI_PASSTHROUGH, QUEUE_FLAG_QUIESCED
and REQ_NOWAIT are missing from blk-mq-debugfs.c. Add these to
blk-mq-debugfs.c such that these appear as names in debugfs instead of
as numbers.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 08:07:44 -06:00
Bart Van Assche
6a934bb814 compat_hdio_ioctl: Fix a declaration
This patch avoids that sparse reports the following warning messages:

block/compat_ioctl.c:85:11: warning: incorrect type in assignment (different address spaces)
block/compat_ioctl.c:85:11:    expected unsigned long *[noderef] <asn:1>p
block/compat_ioctl.c:85:11:    got void [noderef] <asn:1>*
block/compat_ioctl.c:91:21: warning: incorrect type in argument 1 (different address spaces)
block/compat_ioctl.c:91:21:    expected void const volatile [noderef] <asn:1>*<noident>
block/compat_ioctl.c:91:21:    got unsigned long *[noderef] <asn:1>p
block/compat_ioctl.c:87:53: warning: dereference of noderef expression
block/compat_ioctl.c:91:21: warning: dereference of noderef expression

Fixes: commit d597580d37 ("generic ...copy_..._user primitives")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-24 08:40:17 -06:00
weiping zhang
47570848f0 block: remove blk_free_devt in add_partition
put_device(pdev) will call pdev->type->release finally, and blk_free_devt
has been called in part_release(), so remove it.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-24 08:26:57 -06:00
Benjamin Block
50b4d48552 bsg-lib: fix kernel panic resulting from missing allocation of reply-buffer
Since we split the scsi_request out of struct request bsg fails to
provide a reply-buffer for the drivers. This was done via the pointer
for sense-data, that is not preallocated anymore.

Failing to allocate/assign it results in illegal dereferences because
LLDs use this pointer unquestioned.

An example panic on s390x, using the zFCP driver, looks like this (I had
debugging on, otherwise NULL-pointer dereferences wouldn't even panic on
s390x):

Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 6b6b6b6b6b6b6000 TEID: 6b6b6b6b6b6b6403
Fault in home space mode while using kernel ASCE.
AS:0000000001590007 R3:0000000000000024
Oops: 0038 ilc:2 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in: <Long List>
CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.12.0-bsg-regression+ #3
Hardware name: IBM 2964 N96 702 (z/VM 6.4.0)
task: 0000000065cb0100 task.stack: 0000000065cb4000
Krnl PSW : 0704e00180000000 000003ff801e4156 (zfcp_fc_ct_els_job_handler+0x16/0x58 [zfcp])
           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000001 000000005fa9d0d0 000000005fa9d078 0000000000e16866
           000003ff00000290 6b6b6b6b6b6b6b6b 0000000059f78f00 000000000000000f
           00000000593a0958 00000000593a0958 0000000060d88800 000000005ddd4c38
           0000000058b50100 07000000659cba08 000003ff801e8556 00000000659cb9a8
Krnl Code: 000003ff801e4146: e31020500004        lg      %r1,80(%r2)
           000003ff801e414c: 58402040           l       %r4,64(%r2)
          #000003ff801e4150: e35020200004       lg      %r5,32(%r2)
          >000003ff801e4156: 50405004           st      %r4,4(%r5)
           000003ff801e415a: e54c50080000       mvhi    8(%r5),0
           000003ff801e4160: e33010280012       lt      %r3,40(%r1)
           000003ff801e4166: a718fffb           lhi     %r1,-5
           000003ff801e416a: 1803               lr      %r0,%r3
Call Trace:
([<000003ff801e8556>] zfcp_fsf_req_complete+0x726/0x768 [zfcp])
 [<000003ff801ea82a>] zfcp_fsf_reqid_check+0x102/0x180 [zfcp]
 [<000003ff801eb980>] zfcp_qdio_int_resp+0x230/0x278 [zfcp]
 [<00000000009b91b6>] qdio_kick_handler+0x2ae/0x2c8
 [<00000000009b9e3e>] __tiqdio_inbound_processing+0x406/0xc10
 [<00000000001684c2>] tasklet_action+0x15a/0x1d8
 [<0000000000bd28ec>] __do_softirq+0x3ec/0x848
 [<00000000001675a4>] irq_exit+0x74/0xf8
 [<000000000010dd6a>] do_IRQ+0xba/0xf0
 [<0000000000bd19e8>] io_int_handler+0x104/0x2d4
 [<00000000001033b6>] enabled_wait+0xb6/0x188
([<000000000010339e>] enabled_wait+0x9e/0x188)
 [<000000000010396a>] arch_cpu_idle+0x32/0x50
 [<0000000000bd0112>] default_idle_call+0x52/0x68
 [<00000000001cd0fa>] do_idle+0x102/0x188
 [<00000000001cd41e>] cpu_startup_entry+0x3e/0x48
 [<0000000000118c64>] smp_start_secondary+0x11c/0x130
 [<0000000000bd2016>] restart_int_handler+0x62/0x78
 [<0000000000000000>]           (null)
INFO: lockdep is turned off.
Last Breaking-Event-Address:
 [<000003ff801e41d6>] zfcp_fc_ct_job_handler+0x3e/0x48 [zfcp]

Kernel panic - not syncing: Fatal exception in interrupt

This patch moves bsg-lib to allocate and setup struct bsg_job ahead of
time, including the allocation of a buffer for the reply-data.

This means, struct bsg_job is not allocated separately anymore, but as part
of struct request allocation - similar to struct scsi_cmd. Reflect this in
the function names that used to handle creation/destruction of struct
bsg_job.

Reported-by: Steffen Maier <maier@linux.vnet.ibm.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Fixes: 82ed4db499 ("block: split scsi_request out of struct request")
Cc: <stable@vger.kernel.org> #4.11+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-24 08:22:10 -06:00
Milan Broz
97e05463e0 bio-integrity: Fix regression if profile verify_fn is NULL
In dm-integrity target we register integrity profile that have
both generate_fn and verify_fn callbacks set to NULL.

This is used if dm-integrity is stacked under a dm-crypt device
for authenticated encryption (integrity payload contains authentication
tag and IV seed).

In this case the verification is done through own crypto API
processing inside dm-crypt; integrity profile is only holder
of these data. (And memory is owned by dm-crypt as well.)

After the commit (and previous changes)
  Commit 7c20f11680
  Author: Christoph Hellwig <hch@lst.de>
  Date:   Mon Jul 3 16:58:43 2017 -0600

    bio-integrity: stop abusing bi_end_io

we get this crash:

: BUG: unable to handle kernel NULL pointer dereference at   (null)
: IP:   (null)
: *pde = 00000000
...
:
: Workqueue: kintegrityd bio_integrity_verify_fn
: task: f48ae180 task.stack: f4b5c000
: EIP:   (null)
: EFLAGS: 00210286 CPU: 0
: EAX: f4b5debc EBX: 00001000 ECX: 00000001 EDX: 00000000
: ESI: 00001000 EDI: ed25f000 EBP: f4b5dee8 ESP: f4b5dea4
:  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
: CR0: 80050033 CR2: 00000000 CR3: 32823000 CR4: 001406d0
: Call Trace:
:  ? bio_integrity_process+0xe3/0x1e0
:  bio_integrity_verify_fn+0xea/0x150
:  process_one_work+0x1c7/0x5c0
:  worker_thread+0x39/0x380
:  kthread+0xd6/0x110
:  ? process_one_work+0x5c0/0x5c0
:  ? kthread_worker_fn+0x100/0x100
:  ? kthread_worker_fn+0x100/0x100
:  ret_from_fork+0x19/0x24
: Code:  Bad EIP value.
: EIP:   (null) SS:ESP: 0068:f4b5dea4
: CR2: 0000000000000000

Patch just skip the whole verify workqueue if verify_fn is set to NULL.

Fixes: 7c20f116 ("bio-integrity: stop abusing bi_end_io")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
[hch: trivial whitespace fix]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-24 08:16:48 -06:00
Shaohua Li
ea0ea2bc6d blk-throttle: cap discard request size
discard request usually is very big and easily use all bandwidth budget
of a cgroup. discard request size doesn't really mean the size of data
written, so it doesn't make sense to account it into bandwidth budget.
Jens pointed out treating the size 0 doesn't make sense too, because
discard request does have cost. But it's not easy to find the actual
cost. This patch simply makes the size one sector.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 15:56:33 -06:00
weiping zhang
37dcd6570f block, bfq: fix error handle in bfq_init
if elv_register fail, bfq_pool should be free.

Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 15:35:54 -06:00
Christoph Hellwig
74d46992e0 block: replace bi_bdev with a gendisk pointer and partitions index
This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:55 -06:00
Christoph Hellwig
807d4af2f6 block: add a __disk_get_part helper
This helper allows looking up a partion under RCU protection without
grabbing a reference to it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:52 -06:00
Christoph Hellwig
de65b01232 block: reject attempts to allocate more than DISK_MAX_PARTS partitions
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:50 -06:00
Bart Van Assche
130d733a61 block: Warn if blk_queue_rq_timed_out() is called for a blk-mq queue
The timeout handler set by blk_queue_rq_timed_out() is only used
in single queue mode. Calling this function for blk-mq drivers is
wrong. Hence issue a warning if this function is called by a blk-mq
driver.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:02:30 -06:00
Bart Van Assche
4ddd56b003 block: Relax a check in blk_start_queue()
Calling blk_start_queue() from interrupt context with the queue
lock held and without disabling IRQs, as the skd driver does, is
safe. This patch avoids that loading the skd driver triggers the
following warning:

WARNING: CPU: 11 PID: 1348 at block/blk-core.c:283 blk_start_queue+0x84/0xa0
RIP: 0010:blk_start_queue+0x84/0xa0
Call Trace:
 skd_unquiesce_dev+0x12a/0x1d0 [skd]
 skd_complete_internal+0x1e7/0x5a0 [skd]
 skd_complete_other+0xc2/0xd0 [skd]
 skd_isr_completion_posted.isra.30+0x2a5/0x470 [skd]
 skd_isr+0x14f/0x180 [skd]
 irq_forced_thread_fn+0x2a/0x70
 irq_thread+0x144/0x1a0
 kthread+0x125/0x140
 ret_from_fork+0x2a/0x40

Fixes: commit a038e25364 ("[PATCH] blk_start_queue() must be called with irq disabled - add warning")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:45:29 -06:00
Bart Van Assche
6d2cf6f2b4 genhd: Annotate all part and part_tbl pointer dereferences
Annotate gendisk.part_tbl and disk_part_tbl.part dereferences with
rcu_dereference_protected(). This patch does not change the behavior
of the modified code but ensures that sparse does not complain about
disk->part_tbl manipulations nor about part_tbl->part accesses.
Additionally, improve documentation of the locking requirements of
the modified functions.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:36:58 -06:00
Bart Van Assche
f846593391 blk-mq-debugfs: Declare a local symbol static
This was detected by sparse.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:36:58 -06:00
Bart Van Assche
d352ae205d blk-mq: Make blk_mq_reinit_tagset() calls easier to read
Since blk_mq_ops.reinit_request is only called from inside
blk_mq_reinit_tagset(), make this function pointer an argument of
blk_mq_reinit_tagset() instead of a member of struct blk_mq_ops.
This patch does not change any functionality but makes
blk_mq_reinit_tagset() calls easier to read and to analyze.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: James Smart <james.smart@broadcom.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:36:58 -06:00
Bart Van Assche
37f02e5fb3 block: Unexport blk_queue_end_tag()
This function is only used inside the block layer core. Hence
unexport it.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:36:58 -06:00
Bart Van Assche
4d6062193b block: Fix two comments that refer to .queue_rq() return values
Since patch "blk-mq: switch .queue_rq return value to blk_status_t"
.queue_rq() returns a BLK_STS_* value instead of a BLK_MQ_RQ_*
value. Hence refer to the former in comments about .queue_rq()
return values.

Fixes: commit 39a70c76b8 ("blk-mq: clarify dispatch may not be drained/blocked by stopping queue")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:36:58 -06:00
Christoph Hellwig
c005390374 blk-mq-pci: add a fallback when pci_irq_get_affinity returns NULL
While pci_irq_get_affinity should never fail for SMP kernel that
implement the affinity mapping, it will always return NULL in the
UP case, so provide a fallback mapping of all queues to CPU 0 in
that case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:08:14 -06:00
Keith Busch
3280d66a63 blk-mq: Fix queue usage on failed request allocation
blk_mq_get_request() does not release the callers queue usage counter
when allocation fails. The caller still needs to account for its own
queue usage when it is unable to allocate a request.

Fixes: 1ad43c0078 ("blk-mq: don't leak preempt counter/q_usage_counter when allocating rq failed")

Reported-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Tested-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-15 07:22:34 -06:00
Greg Kroah-Hartman
d985524680 Merge 4.13-rc5 into char-misc-next
We want the firmware, and other changes, in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-14 13:29:31 -07:00
Ritesh Harjani
b3193bc0dc cfq: Give a chance for arming slice idle timer in case of group_idle
In below scenario blkio cgroup does not work as per their assigned
weights :-
1. When the underlying device is nonrotational with a single HW queue
with depth of >= CFQ_HW_QUEUE_MIN
2. When the use case is forming two blkio cgroups cg1(weight 1000) &
cg2(wight 100) and two processes(file1 and file2) doing sync IO in
their respective blkio cgroups.

For above usecase result of fio (without this patch):-
file1: (groupid=0, jobs=1): err= 0: pid=685: Thu Jan  1 19:41:49 1970
  write: IOPS=1315, BW=41.1MiB/s (43.1MB/s)(1024MiB/24906msec)
<...>
file2: (groupid=0, jobs=1): err= 0: pid=686: Thu Jan  1 19:41:49 1970
  write: IOPS=1295, BW=40.5MiB/s (42.5MB/s)(1024MiB/25293msec)
<...>
// both the process BW is equal even though they belong to diff.
cgroups with weight of 1000(cg1) and 100(cg2)

In above case (for non rotational NCQ devices),
as soon as the request from cg1 is completed and even
though it is provided with higher set_slice=10, because of CFQ
algorithm when the driver tries to fetch the request, CFQ expires
this group without providing any idle time nor weight priority
and schedules another cfq group (in this case cg2).
And thus both cfq groups(cg1 & cg2) keep alternating to get the
disk time and hence loses the cgroup weight based scheduling.

Below patch gives a chance to cfq algorithm (cfq_arm_slice_timer)
to arm the slice timer in case group_idle is enabled.
In case if group_idle is also not required (including for nonrotational
NCQ drives), we need to explicitly set group_idle = 0 from sysfs for
such cases.

With this patch result of fio(for above usecase) :-
file1: (groupid=0, jobs=1): err= 0: pid=690: Thu Jan  1 00:06:08 1970
  write: IOPS=1706, BW=53.3MiB/s (55.9MB/s)(1024MiB/19197msec)
<..>
file2: (groupid=0, jobs=1): err= 0: pid=691: Thu Jan  1 00:06:08 1970
  write: IOPS=1043, BW=32.6MiB/s (34.2MB/s)(1024MiB/31401msec)
<..>
// In this processes BW is as per their respective cgroups weight.

Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-11 09:00:26 -06:00
Paolo Valente
edaf94285b block, bfq: boost throughput with flash-based non-queueing devices
When a queue associated with a process remains empty, there are cases
where throughput gets boosted if the device is idled to await the
arrival of a new I/O request for that queue. Currently, BFQ assumes
that one of these cases is when the device has no internal queueing
(regardless of the properties of the I/O being served). Unfortunately,
this condition has proved to be too general. So, this commit refines it
as "the device has no internal queueing and is rotational".

This refinement provides a significant throughput boost with random
I/O, on flash-based storage without internal queueing. For example, on
a HiKey board, throughput increases by up to 125%, growing, e.g., from
6.9MB/s to 15.6MB/s with two or three random readers in parallel.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Luca Miccio <lucmiccio@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-11 08:58:03 -06:00
Paolo Valente
d5be3fefc9 block,bfq: refactor device-idling logic
The logic that decides whether to idle the device is scattered across
three functions. Almost all of the logic is in the function
bfq_bfqq_may_idle, but (1) part of the decision is made in
bfq_update_idle_window, and (2) the function bfq_bfqq_must_idle may
switch off idling regardless of the output of bfq_bfqq_may_idle. In
addition, both bfq_update_idle_window and bfq_bfqq_must_idle make
their decisions as a function of parameters that are used, for similar
purposes, also in bfq_bfqq_may_idle. This commit addresses these
issues by moving all the logic into bfq_bfqq_may_idle.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-11 08:58:02 -06:00
Jens Axboe
e743eb1ecd block: remove unused syncfull/asyncfull queue flags
We haven't used these in years, but somehow the definitions still
remained. Kill them, and renumber the QUEUE_FLAG_ space. We had
a hole in the beginning of the space, too.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-10 08:25:38 -06:00
Bart Van Assche
d4acf3650c block: Make blk_mq_delay_kick_requeue_list() rerun the queue at a quiet time
The blk_mq_delay_kick_requeue_list() function is used by the device
mapper and only by the device mapper to rerun the queue and requeue
list after a delay. This function is called once per request that
gets requeued. Modify this function such that the queue is run once
per path change event instead of once per request that is requeued.

Fixes: commit 2849450ad3 ("blk-mq: introduce blk_mq_delay_kick_requeue_list()")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 20:24:38 -06:00
Christoph Hellwig
f86e28c4dc bio-integrity: only verify integrity on the lowest stacked driver
This gets us back to the behavior in 4.12 and earlier.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Fixes: 7c20f116 ("bio-integrity: stop abusing bi_end_io")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 20:24:36 -06:00
Milan Broz
c775d2098d bio-integrity: Fix regression if profile verify_fn is NULL
In dm-integrity target we register integrity profile that have
both generate_fn and verify_fn callbacks set to NULL.

This is used if dm-integrity is stacked under a dm-crypt device
for authenticated encryption (integrity payload contains authentication
tag and IV seed).

In this case the verification is done through own crypto API
processing inside dm-crypt; integrity profile is only holder
of these data. (And memory is owned by dm-crypt as well.)

After the commit (and previous changes)
  Commit 7c20f11680
  Author: Christoph Hellwig <hch@lst.de>
  Date:   Mon Jul 3 16:58:43 2017 -0600

    bio-integrity: stop abusing bi_end_io

we get this crash:

: BUG: unable to handle kernel NULL pointer dereference at   (null)
: IP:   (null)
: *pde = 00000000
...
:
: Workqueue: kintegrityd bio_integrity_verify_fn
: task: f48ae180 task.stack: f4b5c000
: EIP:   (null)
: EFLAGS: 00210286 CPU: 0
: EAX: f4b5debc EBX: 00001000 ECX: 00000001 EDX: 00000000
: ESI: 00001000 EDI: ed25f000 EBP: f4b5dee8 ESP: f4b5dea4
:  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
: CR0: 80050033 CR2: 00000000 CR3: 32823000 CR4: 001406d0
: Call Trace:
:  ? bio_integrity_process+0xe3/0x1e0
:  bio_integrity_verify_fn+0xea/0x150
:  process_one_work+0x1c7/0x5c0
:  worker_thread+0x39/0x380
:  kthread+0xd6/0x110
:  ? process_one_work+0x5c0/0x5c0
:  ? kthread_worker_fn+0x100/0x100
:  ? kthread_worker_fn+0x100/0x100
:  ret_from_fork+0x19/0x24
: Code:  Bad EIP value.
: EIP:   (null) SS:ESP: 0068:f4b5dea4
: CR2: 0000000000000000

Patch just skip the whole verify workqueue if verify_fn is set to NULL.

Fixes: 7c20f116 ("bio-integrity: stop abusing bi_end_io")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
[hch: trivial whitespace fix]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 20:24:26 -06:00
Jens Axboe
b8d62b3a9c blk-mq: enable checking two part inflight counts at the same time
Modify blk_mq_in_flight() to count both a partition and root at
the same time. Then we only have to call it once, instead of
potentially looping the tags twice.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 13:09:33 -06:00
Jens Axboe
f299b7c7a9 blk-mq: provide internal in-flight variant
We don't have to inc/dec some counter, since we can just
iterate the tags. That makes inc/dec a noop, but means we
have to iterate busy tags to get an in-flight count.

Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 13:09:28 -06:00
Jens Axboe
0609e0efc5 block: make part_in_flight() take an array of two ints
Instead of returning the count that matches the partition, pass
in an array of two ints. Index 0 will be filled with the inflight
count for the partition in question, and index 1 will filled
with the root inflight count, if the partition passed in is not the
root.

This is in preparation for being able to calculate both in one
go.

Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 13:09:20 -06:00
Jens Axboe
d62e26b3ff block: pass in queue to inflight accounting
No functional change in this patch, just in preparation for
basing the inflight mechanism on the queue in question.

Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 13:09:16 -06:00
Jens Axboe
7f5562d5ec blk-mq-tag: check for NULL rq when iterating tags
Since we introduced blk-mq-sched, the tags->rqs[] array has been
dynamically assigned. So we need to check for NULL when iterating,
since there's a window of time where the bit is set, but we haven't
dynamically assigned the tags->rqs[] array position yet.

This is perfectly safe, since the memory backing of the request is
never going away while the device is alive.

Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 13:09:08 -06:00
Christoph Hellwig
9346beb9d0 bio-integrity: move the bio integrity profile check earlier in bio_integrity_prep
This makes the code more obvious, and moves the most likely branch first
in the function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-09 10:00:29 -06:00
Sagi Grimberg
24c5dc6610 block: Add rdma affinity based queue mapping helper
Like pci and virtio, we add a rdma helper for affinity
spreading. This achieves optimal mq affinity assignments
according to the underlying rdma device affinity maps.

Reviewed-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-08 14:58:03 -04:00
Jan Kara
3d289d6882 block: Add comment to submit_bio_wait()
submit_bio_wait() does not consume bio reference. Add comment about
that.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-02 08:25:04 -06:00
Ming Lei
1ad43c0078 blk-mq: don't leak preempt counter/q_usage_counter when allocating rq failed
When blk_mq_get_request() failed, preempt counter isn't
released, and blk_mq_make_request() doesn't release the counter
too.

This patch fixes the issue, and makes sure that preempt counter
is only held if rq is allocated successfully. The same policy is
applied on .q_usage_counter too.

Signed-off-by: Ming Lei <minlei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-02 08:23:57 -06:00
Jens Axboe
b7a71e66d4 blk-mq: add warning to __blk_mq_run_hw_queue() for ints disabled
We recently had a bug in the IPR SCSI driver, where it would end up
making the SCSI mid layer run the mq hardware queue with interrupts
disabled. This isn't legal, since the software queue locking relies
on never being grabbed from interrupt context. Additionally, drivers
that set BLK_MQ_F_BLOCKING may schedule from this context.

Add a WARN_ON_ONCE() to catch bad users up front.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-01 09:28:24 -06:00
Paolo Valente
46d556e6aa block, bfq: consider also in_service_entity to state whether an entity is active
Groups of BFQ queues are represented by generic entities in BFQ. When
a queue belonging to a parent entity is deactivated, the parent entity
may need to be deactivated too, in case the deactivated queue was the
only active queue for the parent entity. This deactivation may need to
be propagated upwards if the entity belongs, in its turn, to a further
higher-level entity, and so on. In particular, the upward propagation
of deactivation stops at the first parent entity that remains active
even if one of its child entities has been deactivated.

To decide whether the last non-deactivation condition holds for a
parent entity, BFQ checks whether the field next_in_service is still
not NULL for the parent entity, after the deactivation of one of its
child entity. If it is not NULL, then there are certainly other active
entities in the parent entity, and deactivations can stop.

Unfortunately, this check misses a corner case: if in_service_entity
is not NULL, then next_in_service may happen to be NULL, although the
parent entity is evidently active. This happens if: 1) the entity
pointed by in_service_entity is the only active entity in the parent
entity, and 2) according to the definition of next_in_service, the
in_service_entity cannot be considered as next_in_service. See the
comments on the definition of next_in_service for details on this
second point.

Hitting the above corner case causes crashes.

To address this issue, this commit:
1) Extends the above check on only next_in_service to controlling both
next_in_service and in_service_entity (if any of them is not NULL,
then no further deactivation is performed)
2) Improves the (important) comments on how next_in_service is defined
and updated; in particular it fixes a few rather obscure paragraphs

Reported-by: Eric Wheeler <bfq-sched@lists.ewheeler.net>
Reported-by: Rick Yiu <rick_yiu@htc.com>
Reported-by: Tom X Nguyen <tom81094@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Eric Wheeler <bfq-sched@lists.ewheeler.net>
Tested-by: Rick Yiu <rick_yiu@htc.com>
Tested-by: Laurentiu Nicola <lnicola@dend.ro>
Tested-by: Tom X Nguyen <tom81094@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-29 15:32:49 -06:00
Paolo Valente
6ab1d8da97 block, bfq: reset in_service_entity if it becomes idle
BFQ implements hierarchical scheduling by representing each group of
queues with a generic parent entity. For each parent entity, BFQ
maintains an in_service_entity pointer: if one of the child entities
happens to be in service, in_service_entity points to it.  The
resetting of these pointers happens only on queue expirations: when
the in-service queue is expired, i.e., stops to be the queue in
service, BFQ resets all in_service_entity pointers along the
parent-entity path from this queue to the root entity.

Functions handling the scheduling of entities assume, naturally, that
in-service entities are active, i.e., have pending I/O requests (or,
as a special case, even if they have no pending requests, they are
expected to receive a new request very soon, with the scheduler idling
the storage device while waiting for such an event). Unfortunately,
the above resetting scheme of the in_service_entity pointers may cause
this assumption to be violated.  For example, the in-service queue may
happen to remain without requests because of a request merge. In this
case the queue does become idle, and all related data structures are
updated accordingly. But in_service_entity still points to the queue
in the parent entity. This inconsistency may even propagate to
higher-level parent entities, if they happen to become idle as well,
as a consequence of the leaf queue becoming idle. For this queue and
parent entities, scheduling functions have an undefined behaviour,
and, as reported, may easily lead to kernel crashes or hangs.

This commit addresses this issue by simply resetting the
in_service_entity field also when it is detected to point to an entity
becoming idle (regardless of why the entity becomes idle).

Reported-by: Laurentiu Nicola <lnicola@dend.ro>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Laurentiu Nicola <lnicola@dend.ro>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-29 15:32:47 -06:00
Jens Axboe
18e9781d44 blk-mq: blk_mq_requeue_work() doesn't need to save IRQ flags
We know we're in process context, so don't bother using the
IRQ safe versions of the spin lock.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-29 09:00:03 -06:00
Shaohua Li
35fe6d7632 block: use standard blktrace API to output cgroup info for debug notes
Currently cfq/bfq/blk-throttle output cgroup info in trace in their own
way. Now we have standard blktrace API for this, so convert them to use
it.

Note, this changes the behavior a little bit. cgroup info isn't output
by default, we only do this with 'blk_cgroup' option enabled. cgroup
info isn't output as a string by default too, we only do this with
'blk_cgname' option enabled. Also cgroup info is output in different
position of the note string. I think these behavior changes aren't a big
issue (actually we make trace data shorter which is good), since the
blktrace note is solely for debugging.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-29 09:00:03 -06:00
Shaohua Li
007cc56b7e block: always attach cgroup info into bio
blkcg_bio_issue_check() already gets blkcg for a BIO.
bio_associate_blkcg() uses a percpu refcounter, so it's a very cheap
operation. There is no point we don't attach the cgroup info into bio at
blkcg_bio_issue_check. This also makes blktrace outputs correct cgroup
info.

Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-29 09:00:03 -06:00
Christoph Hellwig
76451d79bd blk-mq: map queues to all present CPUs
We already do this for PCI mappings, and the higher level code now
expects that CPU on/offlining doesn't have an affect on the queue
mappings.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-24 10:01:31 -06:00
Christoph Hellwig
765e40b675 block: disable runtime-pm for blk-mq
The blk-mq code lacks support for looking at the rpm_status field, tracking
active requests and the RQF_PM flag.

Due to the default switch to blk-mq for scsi people start to run into
suspend / resume issue due to this fact, so make sure we disable the runtime
PM functionality until it is properly implemented.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-24 08:46:40 -06:00
Greg Kroah-Hartman
24a81a2c25 Merge 4.13-rc2 into char-misc-next
We want the char/misc driver fixes in here as well to handle future
changes.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-23 19:58:30 -07:00
Logan Gunthorpe
133d55cdb2 block: order /proc/devices by major number
Presently, the order of the block devices listed in /proc/devices is not
entirely sequential. If a block device has a major number greater than
BLKDEV_MAJOR_HASH_SIZE (255), it will be ordered as if its major were
module 255. For example, 511 appears after 1.

This patch cleans that up and prints each major number in the correct
order, regardless of where they are stored in the hash table.

In order to do this, we introduce BLKDEV_MAJOR_MAX as an artificial
limit (chosen to be 512). It will then print all devices in major
order number from 0 to the maximum.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-17 15:42:20 +02:00
Hou Tao
3f7cb4f413 bfq: dispatch request to prevent queue stalling after the request completion
There are mq devices (eg., virtio-blk, nbd and loopback) which don't
invoke blk_mq_run_hw_queues() after the completion of a request.
If bfq is enabled on these devices and the slice_idle attribute or
strict_guarantees attribute is set as zero, it is possible that
after a request completion the remaining requests of busy bfq queue
will stalled in the bfq schedule until a new request arrives.

To fix the scheduler latency problem, we need to check whether or not
all issued requests have completed and dispatch more requests to driver
if there is no request in driver.

The problem can be reproduced by running the following script
on a virtio-blk device with nr_hw_queues as 1:

#!/bin/sh

dev=vdb
# mount point for dev
mp=/tmp/mnt
cd $mp

job=strict.job
cat <<EOF > $job
[global]
direct=1
bs=4k
size=256M
rw=write
ioengine=libaio
iodepth=128
runtime=5
time_based

[1]
filename=1.data

[2]
new_group
filename=2.data
EOF

echo bfq > /sys/block/$dev/queue/scheduler
echo 1 > /sys/block/$dev/queue/iosched/strict_guarantees
fio $job

Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-12 08:32:04 -06:00
Hou Tao
38c9140740 bfq: fix typos in comments about B-WF2Q+ algorithm
The start time of eligible entity should be less than or equal to
the current virtual time, and the entity in idle tree has a finish
time being greater than the current virtual time.

Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-12 08:32:02 -06:00
Linus Torvalds
130568d5ea Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull more block updates from Jens Axboe:
 "This is a followup for block changes, that didn't make the initial
  pull request. It's a bit of a mixed bag, this contains:

   - A followup pull request from Sagi for NVMe. Outside of fixups for
     NVMe, it also includes a series for ensuring that we properly
     quiesce hardware queues when browsing live tags.

   - Set of integrity fixes from Dmitry (mostly), fixing various issues
     for folks using DIF/DIX.

   - Fix for a bug introduced in cciss, with the req init changes. From
     Christoph.

   - Fix for a bug in BFQ, from Paolo.

   - Two followup fixes for lightnvm/pblk from Javier.

   - Depth fix from Ming for blk-mq-sched.

   - Also from Ming, performance fix for mtip32xx that was introduced
     with the dynamic initialization of commands"

* 'for-linus' of git://git.kernel.dk/linux-block: (44 commits)
  block: call bio_uninit in bio_endio
  nvmet: avoid unneeded assignment of submit_bio return value
  nvme-pci: add module parameter for io queue depth
  nvme-pci: compile warnings in nvme_alloc_host_mem()
  nvmet_fc: Accept variable pad lengths on Create Association LS
  nvme_fc/nvmet_fc: revise Create Association descriptor length
  lightnvm: pblk: remove unnecessary checks
  lightnvm: pblk: control I/O flow also on tear down
  cciss: initialize struct scsi_req
  null_blk: fix error flow for shared tags during module_init
  block: Fix __blkdev_issue_zeroout loop
  nvme-rdma: unconditionally recycle the request mr
  nvme: split nvme_uninit_ctrl into stop and uninit
  virtio_blk: quiesce/unquiesce live IO when entering PM states
  mtip32xx: quiesce request queues to make sure no submissions are inflight
  nbd: quiesce request queues to make sure no submissions are inflight
  nvme: kick requeue list when requeueing a request instead of when starting the queues
  nvme-pci: quiesce/unquiesce admin_q instead of start/stop its hw queues
  nvme-loop: quiesce/unquiesce admin_q instead of start/stop its hw queues
  nvme-fc: quiesce/unquiesce admin_q instead of start/stop its hw queues
  ...
2017-07-11 15:36:52 -07:00
Shaohua Li
b222dd2fdd block: call bio_uninit in bio_endio
bio_free isn't a good place to free cgroup info. There are a
lot of cases bio is allocated in special way (for example, in stack) and
never gets called by bio_put hence bio_free, we are leaking memory. This
patch moves the free to bio endio, which should be called anyway. The
bio_uninit call in bio_free is kept, in case the bio never gets called
bio endio.

This assumes ->bi_end_io() doesn't access cgroup info, which seems true
in my audit.

This along with Christoph's integrity patch should fix the memory leak
issue.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-10 12:43:33 -06:00
Linus Torvalds
c856863988 Merge branch 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc compat stuff updates from Al Viro:
 "This part is basically untangling various compat stuff. Compat
  syscalls moved to their native counterparts, getting rid of quite a
  bit of double-copying and/or set_fs() uses. A lot of field-by-field
  copyin/copyout killed off.

   - kernel/compat.c is much closer to containing just the
     copyin/copyout of compat structs. Not all compat syscalls are gone
     from it yet, but it's getting there.

   - ipc/compat_mq.c killed off completely.

   - block/compat_ioctl.c cleaned up; floppy compat ioctls moved to
     drivers/block/floppy.c where they belong. Yes, there are several
     drivers that implement some of the same ioctls. Some are m68k and
     one is 32bit-only pmac. drivers/block/floppy.c is the only one in
     that bunch that can be built on biarch"

* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  mqueue: move compat syscalls to native ones
  usbdevfs: get rid of field-by-field copyin
  compat_hdio_ioctl: get rid of set_fs()
  take floppy compat ioctls to sodding floppy.c
  ipmi: get rid of field-by-field __get_user()
  ipmi: get COMPAT_IPMICTL_RECEIVE_MSG in sync with the native one
  rt_sigtimedwait(): move compat to native
  select: switch compat_{get,put}_fd_set() to compat_{get,put}_bitmap()
  put_compat_rusage(): switch to copy_to_user()
  sigpending(): move compat to native
  getrlimit()/setrlimit(): move compat to native
  times(2): move compat to native
  compat_{get,put}_bitmap(): use unsafe_{get,put}_user()
  fb_get_fscreeninfo(): don't bother with do_fb_ioctl()
  do_sigaltstack(): lift copying to/from userland into callers
  take compat_sys_old_getrlimit() to native syscall
  trim __ARCH_WANT_SYS_OLD_GETRLIMIT
2017-07-06 20:57:13 -07:00
Damien Le Moal
615d22a51c block: Fix __blkdev_issue_zeroout loop
The BIO issuing loop in __blkdev_issue_zeroout() is allocating BIOs
with a maximum number of bvec (pages) equal to

min(nr_sects, (sector_t)BIO_MAX_PAGES)

This works since the requested number of bvecs will always be limited
to the absolute maximum number supported (BIO_MAX_PAGES), but this is
ineficient as too many bvec entries may be requested due to the
different units being used in the min() operation (number of sectors vs
number of pages).
To fix this, introduce the helper __blkdev_sectors_to_bio_pages() to
correctly calculate the number of bvecs for zeroout BIOs as the issuing
loop progresses. The calculation is done using consistent units and
makes sure that the number of pages return is at least 1 (for cases
where the number of sectors is less that the number of sectors in
a page).

Also remove a trailing space after the bit shift in the internal loop
min() call.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-06 09:43:20 -06:00
kbuild test robot
ea4d12dabf bio-integrity: fix boolreturn.cocci warnings
block/bio-integrity.c:318:10-11: WARNING: return of 0/1 in function 'bio_integrity_prep' with return type bool

 Return statements in functions returning bool should use
 true/false instead of 1/0.
Generated by: scripts/coccinelle/misc/boolreturn.cocci

Fixes: e23947bd76 ("bio-integrity: fold bio_integrity_enabled to bio_integrity_prep")
CC: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-04 16:11:53 -06:00
Linus Torvalds
03ffbcdd78 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The irq department delivers:

   - Expand the generic infrastructure handling the irq migration on CPU
     hotplug and convert X86 over to it. (Thomas Gleixner)

     Aside of consolidating code this is a preparatory change for:

   - Finalizing the affinity management for multi-queue devices. The
     main change here is to shut down interrupts which are affine to a
     outgoing CPU and reenabling them when the CPU comes online again.
     That avoids moving interrupts pointlessly around and breaking and
     reestablishing affinities for no value. (Christoph Hellwig)

     Note: This contains also the BLOCK-MQ and NVME changes which depend
     on the rework of the irq core infrastructure. Jens acked them and
     agreed that they should go with the irq changes.

   - Consolidation of irq domain code (Marc Zyngier)

   - State tracking consolidation in the core code (Jeffy Chen)

   - Add debug infrastructure for hierarchical irq domains (Thomas
     Gleixner)

   - Infrastructure enhancement for managing generic interrupt chips via
     devmem (Bartosz Golaszewski)

   - Constification work all over the place (Tobias Klauser)

   - Two new interrupt controller drivers for MVEBU (Thomas Petazzoni)

   - The usual set of fixes, updates and enhancements all over the
     place"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (112 commits)
  irqchip/or1k-pic: Fix interrupt acknowledgement
  irqchip/irq-mvebu-gicp: Allocate enough memory for spi_bitmap
  irqchip/gic-v3: Fix out-of-bound access in gic_set_affinity
  nvme: Allocate queues for all possible CPUs
  blk-mq: Create hctx for each present CPU
  blk-mq: Include all present CPUs in the default queue mapping
  genirq: Avoid unnecessary low level irq function calls
  genirq: Set irq masked state when initializing irq_desc
  genirq/timings: Add infrastructure for estimating the next interrupt arrival time
  genirq/timings: Add infrastructure to track the interrupt timings
  genirq/debugfs: Remove pointless NULL pointer check
  irqchip/gic-v3-its: Don't assume GICv3 hardware supports 16bit INTID
  irqchip/gic-v3-its: Add ACPI NUMA node mapping
  irqchip/gic-v3-its-platform-msi: Make of_device_ids const
  irqchip/gic-v3-its: Make of_device_ids const
  irqchip/irq-mvebu-icu: Add new driver for Marvell ICU
  irqchip/irq-mvebu-gicp: Add new driver for Marvell GICP
  dt-bindings/interrupt-controller: Add DT binding for the Marvell ICU
  genirq/irqdomain: Remove auto-recursive hierarchy support
  irqchip/MSI: Use irq_domain_update_bus_token instead of an open coded access
  ...
2017-07-03 16:50:31 -07:00
Christoph Hellwig
7c20f11680 bio-integrity: stop abusing bi_end_io
And instead call directly into the integrity code from bio_end_io.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 17:00:59 -06:00
Dmitry Monakhov
63573e359d bio-integrity: Restore original iterator on verify stage
Currently ->verify_fn not woks at all because at the moment it is called
bio->bi_iter.bi_size == 0, so we do not iterate integrity bvecs at all.

In order to perform verification we need to know original data vector,
with new bvec rewind API this is trivial.

testcase: 3c6509eaa8

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
[hch: adopted for new status values]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:56:29 -06:00
Dmitry Monakhov
128b6f9fdd t10-pi: Move opencoded contants to common header
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:56:25 -06:00
Dmitry Monakhov
e23947bd76 bio-integrity: fold bio_integrity_enabled to bio_integrity_prep
Currently all integrity prep hooks are open-coded, and if prepare fails
we ignore it's code and fail bio with EIO. Let's return real error to
upper layer, so later caller may react accordingly.

In fact no one want to use bio_integrity_prep() w/o bio_integrity_enabled,
so it is reasonable to fold it in to one function.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
[hch: merged with the latest block tree,
	return bool from bio_integrity_prep]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:56:24 -06:00
Dmitry Monakhov
fbd08e7673 bio-integrity: fix interface for bio_integrity_trim
bio_integrity_trim inherent it's interface from bio_trim and accept
offset and size, but this API is error prone because data offset
must always be insync with bio's data offset. That is why we have
integrity update hook in bio_advance()

So only meaningful values are: offset == 0, sectors == bio_sectors(bio)
Let's just remove them completely.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:56:22 -06:00
Dmitry Monakhov
309a62fa3a bio-integrity: bio_integrity_advance must update integrity seed
SCSI drivers do care about bip_seed so we must update it accordingly.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:56:21 -06:00
Dmitry Monakhov
376a78abf5 bio-integrity: bio_trim should truncate integrity vector accordingly
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:56:19 -06:00
Ming Lei
32825c45ff blk-mq-sched: fix performance regression of mq-deadline
When mq-deadline is taken, IOPS of sequential read and
seqential write is observed more than 20% drop on sata(scsi-mq)
devices, compared with using 'none' scheduler.

The reason is that the default nr_requests for scheduler is
too big for small queuedepth devices, and latency is increased
much.

Since the principle of taking 256 requests for mq scheduler
is based on 128 queue depth, this patch changes into
double size of min(hw queue_depth, 128).

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:54:09 -06:00
Paolo Valente
431b17f9d5 block, bfq: don't change ioprio class for a bfq_queue on a service tree
On each deactivation or re-scheduling (after being served) of a
bfq_queue, BFQ invokes the function __bfq_entity_update_weight_prio(),
to perform pending updates of ioprio, weight and ioprio class for the
bfq_queue. BFQ also invokes this function on I/O-request dispatches,
to raise or lower weights more quickly when needed, thereby improving
latency. However, the entity representing the bfq_queue may be on the
active (sub)tree of a service tree when this happens, and, although
with a very low probability, the bfq_queue may happen to also have a
pending change of its ioprio class. If both conditions hold when
__bfq_entity_update_weight_prio() is invoked, then the entity moves to
a sort of hybrid state: the new service tree for the entity, as
returned by bfq_entity_service_tree(), differs from service tree on
which the entity still is. The functions that handle activations and
deactivations of entities do not cope with such a hybrid state (and
would need to become more complex to cope).

This commit addresses this issue by just making
__bfq_entity_update_weight_prio() not perform also a possible pending
change of ioprio class, when invoked on an I/O-request dispatch for a
bfq_queue. Such a change is thus postponed to when
__bfq_entity_update_weight_prio() is invoked on deactivation or
re-scheduling of the bfq_queue.

Reported-by: Marco Piazza <mpiazza@gmail.com>
Reported-by: Laurentiu Nicola <lnicola@dend.ro>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Marco Piazza <mpiazza@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-07-03 16:50:00 -06:00
Linus Torvalds
9bd42183b9 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Add the SYSTEM_SCHEDULING bootup state to move various scheduler
     debug checks earlier into the bootup. This turns silent and
     sporadically deadly bugs into nice, deterministic splats. Fix some
     of the splats that triggered. (Thomas Gleixner)

   - A round of restructuring and refactoring of the load-balancing and
     topology code (Peter Zijlstra)

   - Another round of consolidating ~20 of incremental scheduler code
     history: this time in terms of wait-queue nomenclature. (I didn't
     get much feedback on these renaming patches, and we can still
     easily change any names I might have misplaced, so if anyone hates
     a new name, please holler and I'll fix it.) (Ingo Molnar)

   - sched/numa improvements, fixes and updates (Rik van Riel)

   - Another round of x86/tsc scheduler clock code improvements, in hope
     of making it more robust (Peter Zijlstra)

   - Improve NOHZ behavior (Frederic Weisbecker)

   - Deadline scheduler improvements and fixes (Luca Abeni, Daniel
     Bristot de Oliveira)

   - Simplify and optimize the topology setup code (Lauro Ramos
     Venancio)

   - Debloat and decouple scheduler code some more (Nicolas Pitre)

   - Simplify code by making better use of llist primitives (Byungchul
     Park)

   - ... plus other fixes and improvements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (103 commits)
  sched/cputime: Refactor the cputime_adjust() code
  sched/debug: Expose the number of RT/DL tasks that can migrate
  sched/numa: Hide numa_wake_affine() from UP build
  sched/fair: Remove effective_load()
  sched/numa: Implement NUMA node level wake_affine()
  sched/fair: Simplify wake_affine() for the single socket case
  sched/numa: Override part of migrate_degrades_locality() when idle balancing
  sched/rt: Move RT related code from sched/core.c to sched/rt.c
  sched/deadline: Move DL related code from sched/core.c to sched/deadline.c
  sched/cpuset: Only offer CONFIG_CPUSETS if SMP is enabled
  sched/fair: Spare idle load balancing on nohz_full CPUs
  nohz: Move idle balancer registration to the idle path
  sched/loadavg: Generalize "_idle" naming to "_nohz"
  sched/core: Drop the unused try_get_task_struct() helper function
  sched/fair: WARN() and refuse to set buddy when !se->on_rq
  sched/debug: Fix SCHED_WARN_ON() to return a value on !CONFIG_SCHED_DEBUG as well
  sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming
  sched/wait: Move bit_wait_table[] and related functionality from sched/core.c to sched/wait_bit.c
  sched/wait: Split out the wait_bit*() APIs from <linux/wait.h> into <linux/wait_bit.h>
  sched/wait: Re-adjust macro line continuation backslashes in <linux/wait.h>
  ...
2017-07-03 13:08:04 -07:00
Linus Torvalds
c6b1e36c8f Merge branch 'for-4.13/block' of git://git.kernel.dk/linux-block
Pull core block/IO updates from Jens Axboe:
 "This is the main pull request for the block layer for 4.13. Not a huge
  round in terms of features, but there's a lot of churn related to some
  core cleanups.

  Note this depends on the UUID tree pull request, that Christoph
  already sent out.

  This pull request contains:

   - A series from Christoph, unifying the error/stats codes in the
     block layer. We now use blk_status_t everywhere, instead of using
     different schemes for different places.

   - Also from Christoph, some cleanups around request allocation and IO
     scheduler interactions in blk-mq.

   - And yet another series from Christoph, cleaning up how we handle
     and do bounce buffering in the block layer.

   - A blk-mq debugfs series from Bart, further improving on the support
     we have for exporting internal information to aid debugging IO
     hangs or stalls.

   - Also from Bart, a series that cleans up the request initialization
     differences across types of devices.

   - A series from Goldwyn Rodrigues, allowing the block layer to return
     failure if we will block and the user asked for non-blocking.

   - Patch from Hannes for supporting setting loop devices block size to
     that of the underlying device.

   - Two series of patches from Javier, fixing various issues with
     lightnvm, particular around pblk.

   - A series from me, adding support for write hints. This comes with
     NVMe support as well, so applications can help guide data placement
     on flash to improve performance, latencies, and write
     amplification.

   - A series from Ming, improving and hardening blk-mq support for
     stopping/starting and quiescing hardware queues.

   - Two pull requests for NVMe updates. Nothing major on the feature
     side, but lots of cleanups and bug fixes. From the usual crew.

   - A series from Neil Brown, greatly improving the bio rescue set
     support. Most notably, this kills the bio rescue work queues, if we
     don't really need them.

   - Lots of other little bug fixes that are all over the place"

* 'for-4.13/block' of git://git.kernel.dk/linux-block: (217 commits)
  lightnvm: pblk: set line bitmap check under debug
  lightnvm: pblk: verify that cache read is still valid
  lightnvm: pblk: add initialization check
  lightnvm: pblk: remove target using async. I/Os
  lightnvm: pblk: use vmalloc for GC data buffer
  lightnvm: pblk: use right metadata buffer for recovery
  lightnvm: pblk: schedule if data is not ready
  lightnvm: pblk: remove unused return variable
  lightnvm: pblk: fix double-free on pblk init
  lightnvm: pblk: fix bad le64 assignations
  nvme: Makefile: remove dead build rule
  blk-mq: map all HWQ also in hyperthreaded system
  nvmet-rdma: register ib_client to not deadlock in device removal
  nvme_fc: fix error recovery on link down.
  nvmet_fc: fix crashes on bad opcodes
  nvme_fc: Fix crash when nvme controller connection fails.
  nvme_fc: replace ioabort msleep loop with completion
  nvme_fc: fix double calls to nvme_cleanup_cmd()
  nvme-fabrics: verify that a controller returns the correct NQN
  nvme: simplify nvme_dev_attrs_are_visible
  ...
2017-07-03 10:34:51 -07:00
Linus Torvalds
81e3e04489 UUID/GUID updates:
- introduce the new uuid_t/guid_t types that are going to replace
    the somewhat confusing uuid_be/uuid_le types and make the terminology
    fit the various specs, as well as the userspace libuuid library.
    (me, based on a previous version from Amir)
  - consolidated generic uuid/guid helper functions lifted from XFS
    and libnvdimm (Amir and me)
  - conversions to the new types and helpers (Amir, Andy and me)
 -----BEGIN PGP SIGNATURE-----
 
 iQI/BAABCAApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAllZfmILHGhjaEBsc3Qu
 ZGUACgkQD55TZVIEUYMvyg/9EvWHOOsSdeDykCK3KdH2uIqnxwpl+m7ljccaGJIc
 MmaH0KnsP9p/Cuw5hESh2tYlmCYN7pmYziNXpf/LRS65/HpEYbs4oMqo8UQsN0UM
 2IXHfXY0HnCoG5OixH8RNbFTkxuGphsTY8meaiDr6aAmqChDQI2yGgQLo3WM2/Qe
 R9N1KoBWH/bqY6dHv+urlFwtsREm2fBH+8ovVma3TO73uZCzJGLJBWy3anmZN+08
 uYfdbLSyRN0T8rqemVdzsZ2SrpHYkIsYGUZV43F581vp8e/3OKMoMxpWRRd9fEsa
 MXmoaHcLJoBsyVSFR9lcx3axKrhAgBPZljASbbA0h49JneWXrzghnKBQZG2SnEdA
 ktHQ2sE4Yb5TZSvvWEKMQa3kXhEfIbTwgvbHpcDr5BUZX8WvEw2Zq8e7+Mi4+KJw
 QkvFC1S96tRYO2bxdJX638uSesGUhSidb+hJ/edaOCB/GK+sLhUdDTJgwDpUGmyA
 xVXTF51ramRS2vhlbzN79x9g33igIoNnG4/PV0FPvpCTSqxkHmPc5mK6Vals1lqt
 cW6XfUjSQECq5nmTBtYDTbA/T+8HhBgSQnrrvmferjJzZUFGr/7MXl+Evz2x4CjX
 OBQoAMu241w6Vp3zoXqxzv+muZ/NLar52M/zbi9TUjE0GvvRNkHvgCC4NmpIlWYJ
 Sxg=
 =J/4P
 -----END PGP SIGNATURE-----

Merge tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid

Pull uuid subsystem from Christoph Hellwig:
 "This is the new uuid subsystem, in which Amir, Andy and I have started
  consolidating our uuid/guid helpers and improving the types used for
  them. Note that various other subsystems have pulled in this tree, so
  I'd like it to go in early.

  UUID/GUID summary:

   - introduce the new uuid_t/guid_t types that are going to replace the
     somewhat confusing uuid_be/uuid_le types and make the terminology
     fit the various specs, as well as the userspace libuuid library.
     (me, based on a previous version from Amir)

   - consolidated generic uuid/guid helper functions lifted from XFS and
     libnvdimm (Amir and me)

   - conversions to the new types and helpers (Amir, Andy and me)"

* tag 'uuid-for-4.13' of git://git.infradead.org/users/hch/uuid: (34 commits)
  ACPI: hns_dsaf_acpi_dsm_guid can be static
  mmc: sdhci-pci: make guid intel_dsm_guid static
  uuid: Take const on input of uuid_is_null() and guid_is_null()
  thermal: int340x_thermal: fix compile after the UUID API switch
  thermal: int340x_thermal: Switch to use new generic UUID API
  acpi: always include uuid.h
  ACPI: Switch to use generic guid_t in acpi_evaluate_dsm()
  ACPI / extlog: Switch to use new generic UUID API
  ACPI / bus: Switch to use new generic UUID API
  ACPI / APEI: Switch to use new generic UUID API
  acpi, nfit: Switch to use new generic UUID API
  MAINTAINERS: add uuid entry
  tmpfs: generate random sb->s_uuid
  scsi_debug: switch to uuid_t
  nvme: switch to uuid_t
  sysctl: switch to use uuid_t
  partitions/ldm: switch to use uuid_t
  overlayfs: use uuid_t instead of uuid_be
  fs: switch ->s_uuid to uuid_t
  ima/policy: switch to use uuid_t
  ...
2017-07-03 09:55:26 -07:00
Al Viro
30138384da compat_hdio_ioctl: get rid of set_fs()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-29 18:17:52 -04:00
Al Viro
229b53c9bf take floppy compat ioctls to sodding floppy.c
all other drivers recognizing those ioctls are very much *not*
biarch.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-06-29 18:17:39 -04:00
Max Gurtovoy
fe631457ff blk-mq: map all HWQ also in hyperthreaded system
This patch performs sequential mapping between CPUs and queues.
In case the system has more CPUs than HWQs then there are still
CPUs to map to HWQs. In hyperthreaded system, map the unmapped CPUs
and their siblings to the same HWQ.
This actually fixes a bug that found unmapped HWQs in a system with
2 sockets, 18 cores per socket, 2 threads per core (total 72 CPUs)
running NVMEoF (opens upto maximum of 64 HWQs).

Performance results running fio (72 jobs, 128 iodepth)
using null_blk (w/w.o patch):

bs      IOPS(read submit_queues=72)   IOPS(write submit_queues=72)   IOPS(read submit_queues=24)  IOPS(write submit_queues=24)
-----  ----------------------------  ------------------------------ ---------------------------- -----------------------------
512    4890.4K/4723.5K                 4524.7K/4324.2K                   4280.2K/4264.3K               3902.4K/3909.5K
1k     4910.1K/4715.2K                 4535.8K/4309.6K                   4296.7K/4269.1K               3906.8K/3914.9K
2k     4906.3K/4739.7K                 4526.7K/4330.6K                   4301.1K/4262.4K               3890.8K/3900.1K
4k     4918.6K/4730.7K                 4556.1K/4343.6K                   4297.6K/4264.5K               3886.9K/3893.9K
8k     4906.4K/4748.9K                 4550.9K/4346.7K                   4283.2K/4268.8K               3863.4K/3858.2K
16k    4903.8K/4782.6K                 4501.5K/4233.9K                   4292.3K/4282.3K               3773.1K/3773.5K
32k    4885.8K/4782.4K                 4365.9K/4184.2K                   4307.5K/4289.4K               3780.3K/3687.3K
64k    4822.5K/4762.7K                 2752.8K/2675.1K                   4308.8K/4312.3K               2651.5K/2655.7K
128k   2388.5K/2313.8K                 1391.9K/1375.7K                   2142.8K/2152.2K               1395.5K/1374.2K

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-29 08:40:11 -06:00
Jens Axboe
9ae3b3f52c block: provide bio_uninit() free freeing integrity/task associations
Wen reports significant memory leaks with DIF and O_DIRECT:

"With nvme devive + T10 enabled, On a system it has 256GB and started
logging /proc/meminfo & /proc/slabinfo for every minute and in an hour
it increased by 15968128 kB or ~15+GB.. Approximately 256 MB / minute
leaking.

/proc/meminfo | grep SUnreclaim...

SUnreclaim:      6752128 kB
SUnreclaim:      6874880 kB
SUnreclaim:      7238080 kB
....
SUnreclaim:     22307264 kB
SUnreclaim:     22485888 kB
SUnreclaim:     22720256 kB

When testcases with T10 enabled call into __blkdev_direct_IO_simple,
code doesn't free memory allocated by bio_integrity_alloc. The patch
fixes the issue. HTX has been run with +60 hours without failure."

Since __blkdev_direct_IO_simple() allocates the bio on the stack, it
doesn't go through the regular bio free. This means that any ancillary
data allocated with the bio through the stack is not freed. Hence, we
can leak the integrity data associated with the bio, if the device is
using DIF/DIX.

Fix this by providing a bio_uninit() and export it, so that we can use
it to free this data. Note that this is a minimal fix for this issue.
Any current user of bio's that are allocated outside of
bio_alloc_bioset() suffers from this issue, most notably some drivers.
We will fix those in a more comprehensive patch for 4.13. This also
means that the commit marked as being fixed by this isn't the real
culprit, it's just the most obvious one out there.

Fixes: 542ff7bf18 ("block: new direct I/O implementation")
Reported-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-28 15:30:13 -06:00
Christoph Hellwig
4b855ad371 blk-mq: Create hctx for each present CPU
Currently we only create hctx for online CPUs, which can lead to a lot
of churn due to frequent soft offline / online operations.  Instead
allocate one for each present CPU to avoid this and dramatically simplify
the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Keith Busch <keith.busch@intel.com>
Cc: linux-block@vger.kernel.org
Cc: linux-nvme@lists.infradead.org
Link: http://lkml.kernel.org/r/20170626102058.10200-3-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-28 23:00:07 +02:00
Christoph Hellwig
5f042e7cbd blk-mq: Include all present CPUs in the default queue mapping
This way we get a nice distribution independent of the current cpu
online / offline state.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Keith Busch <keith.busch@intel.com>
Cc: linux-block@vger.kernel.org
Cc: linux-nvme@lists.infradead.org
Link: http://lkml.kernel.org/r/20170626102058.10200-2-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-06-28 23:00:06 +02:00
Paolo Valente
13c931bd9a block, bfq: update wr_busy_queues if needed on a queue split
This commit fixes a bug triggered by a non-trivial sequence of
events. These events are briefly described in the next two
paragraphs. The impatiens, or those who are familiar with queue
merging and splitting, can jump directly to the last paragraph.

On each I/O-request arrival for a shared bfq_queue, i.e., for a
bfq_queue that is the result of the merge of two or more bfq_queues,
BFQ checks whether the shared bfq_queue has become seeky (i.e., if too
many random I/O requests have arrived for the bfq_queue; if the device
is non rotational, then random requests must be also small for the
bfq_queue to be tagged as seeky). If the shared bfq_queue is actually
detected as seeky, then a split occurs: the bfq I/O context of the
process that has issued the request is redirected from the shared
bfq_queue to a new non-shared bfq_queue. As a degenerate case, if the
shared bfq_queue actually happens to be shared only by one process
(because of previous splits), then no new bfq_queue is created: the
state of the shared bfq_queue is just changed from shared to non
shared.

Regardless of whether a brand new non-shared bfq_queue is created, or
the pre-existing shared bfq_queue is just turned into a non-shared
bfq_queue, several parameters of the non-shared bfq_queue are set
(restored) to the original values they had when the bfq_queue
associated with the bfq I/O context of the process (that has just
issued an I/O request) was merged with the shared bfq_queue. One of
these parameters is the weight-raising state.

If, on the split of a shared bfq_queue,
1) a pre-existing shared bfq_queue is turned into a non-shared
bfq_queue;
2) the previously shared bfq_queue happens to be busy;
3) the weight-raising state of the previously shared bfq_queue happens
to change;
the number of weight-raised busy queues changes. The field
wr_busy_queues must then be updated accordingly, but such an update
was missing. This commit adds the missing update.

Reported-by: Luca Miccio <lucmiccio@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:30:47 -06:00
Christoph Hellwig
8fc450443e block: don't set bounce limit in blk_init_queue
Instead move it to the callers.  Those that either don't use bio_data() or
page_address() or are specific to architectures that do not support highmem
are skipped.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:13:45 -06:00
Christoph Hellwig
0bf6595ec8 block: don't set bounce limit in blk_init_allocated_queue
And just move it into scsi_transport_sas which needs it due to low-level
drivers directly derferencing bio_data, and into blk_init_queue_node,
which will need a further push into the callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:13:45 -06:00
Christoph Hellwig
46685d1a95 blk-mq: don't bounce by default
For historical reasons we default to bouncing highmem pages for all block
queues.  But the blk-mq drivers are easy to audit to ensure that we don't
need this - scsi and mtip32xx set explicit limits and everyone else doesn't
have any particular ones.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:13:45 -06:00
Christoph Hellwig
0b0bcacc3b block: don't bother with bounce limits for make_request drivers
We only call blk_queue_bounce for request-based drivers, so stop messing
with it for make_request based drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:13:45 -06:00
Christoph Hellwig
1c4bc3ab9a block: remove the queue_bounce_pfn helper
Only used inside the bounce code, and opencoding it makes it more obvious
what is going on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:13:45 -06:00
Christoph Hellwig
3bce016a4c block: move bounce declarations to block/blk.h
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:13:45 -06:00
Christoph Hellwig
caa4b02476 blk-map: call blk_queue_bounce from blk_rq_append_bio
This makes moves the knowledge about bouncing out of the callers into the
block core (just like we do for the normal I/O path), and allows to unexport
blk_queue_bounce.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:13:21 -06:00
Jens Axboe
f793dfd3f3 blk-mq: expose write hints through debugfs
Useful to verify that things are working the way they should.
Reading the file will return number of kb written with each
write hint. Writing the file will reset the statistics. No care
is taken to ensure that we don't race on updates.

Drivers will write to q->write_hints[] if they handle a given
write hint.

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:31 -06:00
Jens Axboe
cb6934f8ea block: add support for write hints in a bio
No functional changes in this patch, we just use up some holes
in the bio and request structures to define a write hint that
we psas down the stack.

Ensure that we don't merge requests that have different life time
hints assigned to them, and that we inherit the write hint when
cloning a bio.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-27 12:05:27 -06:00
Ingo Molnar
1bc3cd4dfa Merge branch 'linus' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-24 08:57:20 +02:00
Jens Axboe
f95a0d6a95 Merge commit '8e8320c9315c' into for-4.13/block
Pull in the fix for shared tags, as it conflicts with the pending
changes in for-4.13/block. We already pulled in v4.12-rc5 to solve
other conflicts or get fixes that went into 4.12, so not a lot
of changes in this merge.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-22 21:55:24 -06:00
weiping
a9590fe148 blk-mq: remove double set queue_num
hwctx's queue_num has been set prior call blk_mq_init_hctx, so no need
set it again.

Signed-off-by: weiping <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-22 09:18:25 -06:00
Bart Van Assche
852ec80983 blk-mq: Make it safe to quiesce and unquiesce from an interrupt handler
Since blk_mq_quiesce_queue_nowait() can be called from interrupt
context, make this safe. Since this function is not in the hot
path, uninline it.

Fixes: commit f4560ffe8c ("blk-mq: use QUEUE_FLAG_QUIESCED to quiesce queue")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-21 12:01:15 -06:00
Bart Van Assche
34bd9c1c4f block: Fix off-by-one errors in blk_status_to_errno() and print_req_error()
This was detected by the smatch static analyzer.

Fixes: commit 2a842acab1 ("block: introduce new block status code type")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-21 12:01:14 -06:00
Bart Van Assche
e0fc443a86 block: Declare local symbols static
Avoid that building with W=1 causes the compiler to complain that
a declaration for bounce_bio_set and bounce_bio_split is missing.

References: commit a8821f3f32 ("block: Improvements to bounce-buffer handling")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Neil Brown <neilb@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-21 12:01:13 -06:00
Bart Van Assche
e29387ebd8 block: Add fallthrough markers to switch statements
This patch suppresses gcc 7 warnings about falling through in switch
statements when building with W=1. From the gcc documentation: The
-Wimplicit-fallthrough=3 warning is enabled by -Wextra. See also
https://gcc.gnu.org/onlinedocs/gcc-7.1.0/gcc/Warning-Options.html.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-21 11:46:07 -06:00
Jens Axboe
8e8320c931 blk-mq: fix performance regression with shared tags
If we have shared tags enabled, then every IO completion will trigger
a full loop of every queue belonging to a tag set, and every hardware
queue for each of those queues, even if nothing needs to be done.
This causes a massive performance regression if you have a lot of
shared devices.

Instead of doing this huge full scan on every IO, add an atomic
counter to the main queue that tracks how many hardware queues have
been marked as needing a restart. With that, we can avoid looking for
restartable queues, if we don't have to.

Max reports that this restores performance. Before this patch, 4K
IOPS was limited to 22-23K IOPS. With the patch, we are running at
950-970K IOPS.

Fixes: 6d8c6c0f97 ("blk-mq: Restart a single queue if tag sets are shared")
Reported-by: Max Gurtovoy <maxg@mellanox.com>
Tested-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Tested-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-21 10:17:49 -06:00
Bart Van Assche
5435c023b9 blk-mq: Warn when attempting to run a hardware queue that is not mapped
A queue must be frozen while the mapped state of a hardware queue
is changed. Additionally, any change of the mapped state is
followed by a call to blk_mq_map_swqueue() (see also
blk_mq_init_allocated_queue() and blk_mq_update_nr_hw_queues()).
Since blk_mq_map_swqueue() does not map any unmapped hardware
queue onto any software queue, no attempt will be made to run
an unmapped hardware queue. Hence issue a warning upon attempts
to run an unmapped hardware queue.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
edf8ff5588 block: Constify disk_type
The variable 'disk_type' is never modified so constify it.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
7b6078146c blk-mq: Document locking assumptions
Document the locking assumptions in functions that modify
blk_mq_ctx.rq_list to make it easier for humans to verify
this code.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
332ebbf7f9 block: Document what queue type each function is intended for
Some functions in block/blk-core.c must only be used on blk-sq queues
while others are safe to use against any queue type. Document which
functions are intended for blk-sq queues and issue a warning if the
blk-sq API is misused. This does not only help block driver authors
but will also make it easier to remove the blk-sq code once that code
is declared obsolete.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
2fff8a924d block: Check locking assumptions at runtime
Instead of documenting the locking assumptions of most block layer
functions as a comment, use lockdep_assert_held() to verify locking
assumptions at runtime.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
c3a148d20a blk-mq: Initialize .rq_flags in blk_mq_rq_ctx_init()
Initialization of blk-mq requests is a bit weird: blk_mq_rq_ctx_init()
is called after a value has been assigned to .rq_flags and .rq_flags
is initialized in __blk_mq_finish_request(). Initialize .rq_flags in
blk_mq_rq_ctx_init() instead of relying on __blk_mq_finish_request().
Moving the initialization of .rq_flags is fine because all changes
and tests of .rq_flags occur between blk_get_request() and finishing
a request.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
c8d9cf22cf block: Change argument type of scsi_req_init()
Since scsi_req_init() works on a struct scsi_request, change the
argument type into struct scsi_request *.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
ca18d6f769 block: Make most scsi_req_init() calls implicit
Instead of explicitly calling scsi_req_init() after blk_get_request(),
call that function from inside blk_get_request(). Add an
.initialize_rq_fn() callback function to the block drivers that need
it. Merge the IDE .init_rq_fn() function into .initialize_rq_fn()
because it is too small to keep it as a separate function. Keep the
scsi_req_init() call in ide_prep_sense() because it follows a
blk_rq_init() call.

References: commit 82ed4db499 ("block: split scsi_request out of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
d280bab305 block: Introduce request_queue.initialize_rq_fn()
Several block drivers need to initialize the driver-private request
data after having called blk_get_request() and before .prep_rq_fn()
is called, e.g. when submitting a REQ_OP_SCSI_* request. Avoid that
that initialization code has to be repeated after every
blk_get_request() call by adding new callback functions to struct
request_queue and to struct blk_mq_ops.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
cd6ce1482f block: Make request operation type argument declarations consistent
Instead of declaring the second argument of blk_*_get_request()
as int and passing it to functions that expect an unsigned int,
declare that second argument as unsigned int. Also because of
consistency, rename that second argument from 'rw' into 'op'.
This patch does not change any functionality.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Bart Van Assche
0731967877 blk-mq: Reduce blk_mq_hw_ctx size
Since the srcu structure is rather large (184 bytes on an x86-64
system with kernel debugging disabled), only allocate it if needed.

Reported-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 19:27:14 -06:00
Goldwyn Rodrigues
03a07c92a9 block: return on congested block device
A new bio operation flag REQ_NOWAIT is introduced to identify bio's
orignating from iocb with IOCB_NOWAIT. This flag indicates
to return immediately if a request cannot be made instead
of retrying.

Stacked devices such as md (the ones with make_request_fn hooks)
currently are not supported because it may block for housekeeping.
For example, an md can have a part of the device suspended.
For this reason, only request based devices are supported.
In the future, this feature will be expanded to stacked devices
by teaching them how to handle the REQ_NOWAIT flags.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-20 07:12:03 -06:00
Ingo Molnar
2055da9738 sched/wait: Disambiguate wq_entry->task_list and wq_head->task_list naming
So I've noticed a number of instances where it was not obvious from the
code whether ->task_list was for a wait-queue head or a wait-queue entry.

Furthermore, there's a number of wait-queue users where the lists are
not for 'tasks' but other entities (poll tables, etc.), in which case
the 'task_list' name is actively confusing.

To clear this all up, name the wait-queue head and entry list structure
fields unambiguously:

	struct wait_queue_head::task_list	=> ::head
	struct wait_queue_entry::task_list	=> ::entry

For example, this code:

	rqw->wait.task_list.next != &wait->task_list

... is was pretty unclear (to me) what it's doing, while now it's written this way:

	rqw->wait.head.next != &wait->entry

... which makes it pretty clear that we are iterating a list until we see the head.

Other examples are:

	list_for_each_entry_safe(pos, next, &x->task_list, task_list) {
	list_for_each_entry(wq, &fence->wait.task_list, task_list) {

... where it's unclear (to me) what we are iterating, and during review it's
hard to tell whether it's trying to walk a wait-queue entry (which would be
a bug), while now it's written as:

	list_for_each_entry_safe(pos, next, &x->head, entry) {
	list_for_each_entry(wq, &fence->wait.head, entry) {

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:19:14 +02:00
Ingo Molnar
ac6424b981 sched/wait: Rename wait_queue_t => wait_queue_entry_t
Rename:

	wait_queue_t		=>	wait_queue_entry_t

'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue",
but in reality it's a queue *entry*. The 'real' queue is the wait queue head,
which had to carry the name.

Start sorting this out by renaming it to 'wait_queue_entry_t'.

This also allows the real structure name 'struct __wait_queue' to
lose its double underscore and become 'struct wait_queue_entry',
which is the more canonical nomenclature for such data types.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:18:27 +02:00
Ming Lei
641a9ed60f Revert "blk-mq: don't use sync workqueue flushing from drivers"
This patch reverts commit 2719aa217e0d02(blk-mq: don't use
sync workqueue flushing from drivers) because only
blk_mq_quiesce_queue() need the sync flush, and now
we don't need to stop queue any more, so revert it.

Also changes to cancel_delayed_work() in blk_mq_stop_hw_queue().

Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 14:24:48 -06:00
Ming Lei
39a70c76b8 blk-mq: clarify dispatch may not be drained/blocked by stopping queue
BLK_MQ_S_STOPPED may not be observed in other concurrent I/O paths,
we can't guarantee that dispatching won't happen after returning
from the APIs of stopping queue.

So clarify the fact and avoid potential misuse.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 14:24:48 -06:00
Ming Lei
1d9e9bc6b5 blk-mq: don't stop queue for quiescing
Queue can be started by other blk-mq APIs and can be used in
different cases, this limits uses of blk_mq_quiesce_queue()
if it is based on stopping queue, and make its usage very
difficult, especially users have to use the stop queue APIs
carefully for avoiding to break blk_mq_quiesce_queue().

We have applied the QUIESCED flag for draining and blocking
dispatch, so it isn't necessary to stop queue any more.

After stopping queue is removed, blk_mq_quiesce_queue() can
be used safely and easily, then users won't worry about queue
restarting during quiescing at all.

Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 14:24:48 -06:00
Ming Lei
69e07c4adb blk-mq: update comments on blk_mq_quiesce_queue()
Actually what we want to get from blk_mq_quiesce_queue()
isn't only to wait for completion of all ongoing .queue_rq().

In the typical context of canceling requests, we need to
make sure that the following is done in the dispatch path
before starting to cancel requests:

	- failed dispatched request is finished
	- busy dispatched request is requeued, and the STARTED
	flag is cleared

So update comment to keep code, doc and our expection consistent.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 14:24:48 -06:00
Ming Lei
f4560ffe8c blk-mq: use QUEUE_FLAG_QUIESCED to quiesce queue
It is required that no dispatch can happen any more once
blk_mq_quiesce_queue() returns, and we don't have such requirement
on APIs of stopping queue.

But blk_mq_quiesce_queue() still may not block/drain dispatch in the
the case of BLK_MQ_S_START_ON_RUN, so use the new introduced flag of
QUEUE_FLAG_QUIESCED and evaluate it inside RCU read-side critical
sections for fixing this issue.

Also blk_mq_quiesce_queue() is implemented via stopping queue, which
limits its uses, and easy to cause race, because any queue restart in
other paths may break blk_mq_quiesce_queue(). With the introduced
flag of QUEUE_FLAG_QUIESCED, we don't need to depend on stopping queue
for quiescing any more.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 14:24:27 -06:00
Ming Lei
e4e739131a blk-mq: introduce blk_mq_unquiesce_queue
blk_mq_start_stopped_hw_queues() is used implictly
as counterpart of blk_mq_quiesce_queue() for unquiescing queue,
so we introduce blk_mq_unquiesce_queue() and make it
as counterpart of blk_mq_quiesce_queue() explicitly.

This function is for improving the current quiescing mechanism
in the following patches.

Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 14:20:04 -06:00
NeilBrown
58c94cc19e block: don't check for BIO_MAX_PAGES in blk_bio_segment_split()
blk_bio_segment_split() makes sure bios have no more than
BIO_MAX_PAGES entries in the bi_io_vec.
This was done because bio_clone_bioset() (when given a
mempool bioset) could not handle larger io_vecs.

No driver uses bio_clone_bioset() any more, they all
use bio_clone_fast() if anything, and bio_clone_fast()
doesn't clone the bi_io_vec.

The main user of of bio_clone_bioset() at this level
is bounce.c, and bouncing now happens before blk_bio_segment_split(),
so that is not of concern.

So remove the big helpful comment and the code.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 12:40:59 -06:00
NeilBrown
9b10f6a9c2 block: remove bio_clone() and all references.
bio_clone() is no longer used.
Only bio_clone_bioset() or bio_clone_fast().
This is for the best, as bio_clone() used fs_bio_set,
and filesystems are unlikely to want to use bio_clone().

So remove bio_clone() and all references.
This includes a fix to some incorrect documentation.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 12:40:59 -06:00
NeilBrown
a8821f3f32 block: Improvements to bounce-buffer handling
Since commit 23688bf4f8 ("block: ensure to split after potentially
bouncing a bio") blk_queue_bounce() is called *before*
blk_queue_split().
This means that:
 1/ the comments blk_queue_split() about bounce buffers are
    irrelevant, and
 2/ a very large bio (more than BIO_MAX_PAGES) will no longer be
    split before it arrives at blk_queue_bounce(), leading to the
    possibility that bio_clone_bioset() will fail and a NULL
    will be dereferenced.

Separately, blk_queue_bounce() shouldn't use fs_bio_set as the bio
being copied could be from the same set, and this could lead to a
deadlock.

So:
 - allocate 2 private biosets for blk_queue_bounce, one for
   splitting enormous bios and one for cloning bios.
 - add code to split a bio that exceeds BIO_MAX_PAGES.
 - Fix up the comments in blk_queue_split()

Credit-to: Ming Lei <tom.leiming@gmail.com> (suggested using single bio_for_each_segment loop)
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 12:40:59 -06:00
NeilBrown
93b27e7290 blk: use non-rescuing bioset for q->bio_split.
A rescuing bioset is only useful if there might be bios from
that same bioset on the bio_list_on_stack queue at a time
when bio_alloc_bioset() is called.  This never applies to
q->bio_split.

Allocations from q->bio_split are only ever made from
blk_queue_split() which is only ever called early in each of
various make_request_fn()s.  The original bio (call this A)
is then passed to generic_make_request() and is placed on
the bio_list_on_stack queue, and the bio that was allocated
from q->bio_split (B) is processed.

The processing of this may cause other bios to be passed to
generic_make_request() or may even cause the bio B itself to
be passed, possible after some prefix has been split off
(using some other bioset).

generic_make_request() now guarantees that all of these bios
(B and dependants) will be fully processed before the tail
of the original bio A gets handled.  None of these early bios
can possible trigger an allocation from the original
q->bio_split as they are either too small to require
splitting or (more likely) are destined for a different queue.

The next time that the original q->bio_split might be used
by this thread is when A is processed again, as it might
still be too big to handle directly.  By this time there
cannot be any other bios allocated from q->bio_split in the
generic_make_request() queue.  So no rescuing will ever be
needed.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 12:40:59 -06:00
NeilBrown
47e0fb461f blk: make the bioset rescue_workqueue optional.
This patch converts bioset_create() to not create a workqueue by
default, so alloctions will never trigger punt_bios_to_rescuer().  It
also introduces a new flag BIOSET_NEED_RESCUER which tells
bioset_create() to preserve the old behavior.

All callers of bioset_create() that are inside block device drivers,
are given the BIOSET_NEED_RESCUER flag.

biosets used by filesystems or other top-level users do not
need rescuing as the bio can never be queued behind other
bios.  This includes fs_bio_set, blkdev_dio_pool,
btrfs_bioset, xfs_ioend_bioset, and one allocated by
target_core_iblock.c.

biosets used by md/raid do not need rescuing as
their usage was recently audited and revised to never
risk deadlock.

It is hoped that most, if not all, of the remaining biosets
can end up being the non-rescued version.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Credit-to: Ming Lei <ming.lei@redhat.com> (minor fixes)
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 12:40:59 -06:00
NeilBrown
011067b056 blk: replace bioset_create_nobvec() with a flags arg to bioset_create()
"flags" arguments are often seen as good API design as they allow
easy extensibility.
bioset_create_nobvec() is implemented internally as a variation in
flags passed to __bioset_create().

To support future extension, make the internal structure part of the
API.
i.e. add a 'flags' argument to bioset_create() and discard
bioset_create_nobvec().

Note that the bio_split allocations in drivers/md/raid* do not need
the bvec mempool - they should have used bioset_create_nobvec().

Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 12:40:59 -06:00
NeilBrown
af67c31fba blk: remove bio_set arg from blk_queue_split()
blk_queue_split() is always called with the last arg being q->bio_split,
where 'q' is the first arg.

Also blk_queue_split() sometimes uses the passed-in 'bs' and sometimes uses
q->bio_split.

This is inconsistent and unnecessary.  Remove the last arg and always use
q->bio_split inside blk_queue_split()

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Credit-to: Javier González <jg@lightnvm.io> (Noticed that lightnvm was missed)
Reviewed-by: Javier González <javier@cnexlabs.com>
Tested-by: Javier González <javier@cnexlabs.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 12:40:59 -06:00
Christoph Hellwig
e4cdf1a1cb blk-mq: remove __blk_mq_alloc_request
Move most code into blk_mq_rq_ctx_init, and the rest into
blk_mq_get_request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
5bbf4e5a8e blk-mq-sched: unify request prepare methods
This patch makes sure we always allocate requests in the core blk-mq
code and use a common prepare_request method to initialize them for
both mq I/O schedulers.  For Kyber and additional limit_depth method
is added that is called before allocating the request.

Also because none of the intializations can really fail the new method
does not return an error - instead the bfq finish method is hardened
to deal with the no-IOC case.

Last but not least this removes the abuse of RQF_QUEUE by the blk-mq
scheduling code as RQF_ELFPRIV is all that is needed now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
44e8c2bff8 blk-mq: refactor blk_mq_sched_assign_ioc
blk_mq_sched_assign_ioc now only handles the assigned of the ioc if
the schedule needs it (bfq only at the moment).  The caller to the
per-request initializer is moved out so that it can be merged with
a similar call for the kyber I/O scheduler.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
9f21073826 bfq-iosched: fix NULL ioc check in bfq_get_rq_private
icq_to_bic is a container_of operation, so we need to check for NULL
before it.  Also move the check outside the spinlock while we're at
it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
037cebb85b blk-mq: streamline blk_mq_get_request
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
6af54051a0 blk-mq: simplify blk_mq_free_request
Merge three functions only tail-called by blk_mq_free_request into
blk_mq_free_request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
7b9e936163 blk-mq-sched: unify request finished methods
No need to have two different callouts of bfq vs kyber.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
ea511e3c28 blk-mq: remove blk_mq_sched_{get,put}_rq_priv
Having these as separate helpers in a header really does not help
readability, or my chances to refactor this code sanely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
d2c0d38324 blk-mq: move blk_mq_sched_{get,put}_request to blk-mq.c
Having them out of line in blk-mq-sched.c just makes the code flow
unnecessarily complicated.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Christoph Hellwig
6e15cf2a0b blk-mq: mark blk_mq_rq_ctx_init static
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-18 10:08:55 -06:00
Jens Axboe
c27b2d634f Merge branch 'nvme-4.13' of git://git.infradead.org/nvme into for-4.13/block
Pull NVMe changes for 4.13 from Christoph:

Highlights:

 - UUID identifier support from Johannes
 - Lots of cleanups from Sagi
 - Host Memory Buffer support from me

And lots of cleanups and smaller fixes of course.

Note that the UUID identifier changes are based on top of the uuid tree.
I am the maintainer of that tree and will send it to Linus as soon as
4.12 is released as various other trees depend on it as well (and the
diffstat includes those changes unfortunately)
2017-06-16 10:14:59 -06:00
Bart Van Assche
a462b95083 block: Dedicated error code fixups
This patch fixes two sparse warnings introduced by the "dedicated
error codes for the block layer V3" patch series. These changes
have not been tested.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-16 09:47:15 -06:00
Bart Van Assche
dc9edc44de block: Fix a blk_exit_rl() regression
Avoid that the following complaint is reported:

 BUG: sleeping function called from invalid context at kernel/workqueue.c:2790
 in_atomic(): 1, irqs_disabled(): 0, pid: 41, name: rcuop/3
 1 lock held by rcuop/3/41:
  #0:  (rcu_callback){......}, at: [<ffffffff8111f9a2>] rcu_nocb_kthread+0x282/0x500
 Call Trace:
  dump_stack+0x86/0xcf
  ___might_sleep+0x174/0x260
  __might_sleep+0x4a/0x80
  flush_work+0x7e/0x2e0
  __cancel_work_timer+0x143/0x1c0
  cancel_work_sync+0x10/0x20
  blk_throtl_exit+0x25/0x60
  blkcg_exit_queue+0x35/0x40
  blk_release_queue+0x42/0x130
  kobject_put+0xa9/0x190

This happens since we invoke callbacks that need to block from the
queue release handler. Fix this by pushing the final release to
a workqueue.

Reported-by: Ross Zwisler <zwisler@gmail.com>
Fixes: commit b425e50492 ("block: Avoid that blk_exit_rl() triggers a use-after-free")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>

Updated changelog
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-14 13:27:50 -06:00
Christoph Hellwig
fdd050b5b3 Merge branch 'uuid-types' of bombadil.infradead.org:public_git/uuid into nvme-base 2017-06-13 11:45:14 +02:00
Jens Axboe
f06345add9 blk-mq: fixup type of 'ret' in __blk_mq_try_issue_directly()
Should be a blk_status_t type, not an integer.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-12 11:22:46 -06:00
Jens Axboe
8f66439eec Linux 4.12-rc5
-----BEGIN PGP SIGNATURE-----
 
 iQEcBAABAgAGBQJZPdbLAAoJEHm+PkMAQRiGx4wH/1nCjfnl6fE8oJ24/1gEAOUh
 biFdqJkYZmlLYHVtYfLm4Ueg4adJdg0wx6qM/4RaAzmQVvLfDV34bc1qBf1+P95G
 kVF+osWyXrZo5cTwkwapHW/KNu4VJwAx2D1wrlxKDVG5AOrULH1pYOYGOpApEkZU
 4N+q5+M0ce0GJpqtUZX+UnI33ygjdDbBxXoFKsr24B7eA0ouGbAJ7dC88WcaETL+
 2/7tT01SvDMo0jBSV0WIqlgXwZ5gp3yPGnklC3F4159Yze6VFrzHMKS/UpPF8o8E
 W9EbuzwxsKyXUifX2GY348L1f+47glen/1sedbuKnFhP6E9aqUQQJXvEO7ueQl4=
 =m2Gx
 -----END PGP SIGNATURE-----

Merge tag 'v4.12-rc5' into for-4.13/block

We've already got a few conflicts and upcoming work depends on some of the
changes that have gone into mainline as regression fixes for this series.

Pull in 4.12-rc5 to resolve these conflicts and make it easier on down stream
trees to continue working on 4.13 changes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-06-12 08:30:13 -06:00
Christoph Hellwig
4e4cbee93d block: switch bios to blk_status_t
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Christoph Hellwig
fc17b6534e blk-mq: switch ->queue_rq return value to blk_status_t
Use the same values for use for request completion errors as the return
value from ->queue_rq.  BLK_STS_RESOURCE is special cased to cause
a requeue, and all the others are completed as-is.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Christoph Hellwig
2a842acab1 block: introduce new block status code type
Currently we use nornal Linux errno values in the block layer, and while
we accept any error a few have overloaded magic meanings.  This patch
instead introduces a new  blk_status_t value that holds block layer specific
status codes and explicitly explains their meaning.  Helpers to convert from
and to the previous special meanings are provided for now, but I suspect
we want to get rid of them in the long run - those drivers that have a
errno input (e.g. networking) usually get errnos that don't know about
the special block layer overloads, and similarly returning them to userspace
will usually return somethings that strictly speaking isn't correct
for file system operations, but that's left as an exercise for later.

For now the set of errors is a very limited set that closely corresponds
to the previous overloaded errno values, but there is some low hanging
fruite to improve it.

blk_status_t (ab)uses the sparse __bitwise annotations to allow for sparse
typechecking, so that we can easily catch places passing the wrong values.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Paolo Valente
8f9bebc33d block, bfq: access and cache blkg data only when safe
In blk-cgroup, operations on blkg objects are protected with the
request_queue lock. This is no more the lock that protects
I/O-scheduler operations in blk-mq. In fact, the latter are now
protected with a finer-grained per-scheduler-instance lock. As a
consequence, although blkg lookups are also rcu-protected, blk-mq I/O
schedulers may see inconsistent data when they access blkg and
blkg-related objects. BFQ does access these objects, and does incur
this problem, in the following case.

The blkg_lookup performed in bfq_get_queue, being protected (only)
through rcu, may happen to return the address of a copy of the
original blkg. If this is the case, then the blkg_get performed in
bfq_get_queue, to pin down the blkg, is useless: it does not prevent
blk-cgroup code from destroying both the original blkg and all objects
directly or indirectly referred by the copy of the blkg. BFQ accesses
these objects, which typically causes a crash for NULL-pointer
dereference of memory-protection violation.

Some additional protection mechanism should be added to blk-cgroup to
address this issue. In the meantime, this commit provides a quick
temporary fix for BFQ: cache (when safe) blkg data that might
disappear right after a blkg_lookup.

In particular, this commit exploits the following facts to achieve its
goal without introducing further locks.  Destroy operations on a blkg
invoke, as a first step, hooks of the scheduler associated with the
blkg. And these hooks are executed with bfqd->lock held for BFQ. As a
consequence, for any blkg associated with the request queue an
instance of BFQ is attached to, we are guaranteed that such a blkg is
not destroyed, and that all the pointers it contains are consistent,
while that instance is holding its bfqd->lock. A blkg_lookup performed
with bfqd->lock held then returns a fully consistent blkg, which
remains consistent until this lock is held. In more detail, this holds
even if the returned blkg is a copy of the original one.

Finally, also the object describing a group inside BFQ needs to be
protected from destruction on the blkg_free of the original blkg
(which invokes bfq_pd_free). This commit adds private refcounting for
this object, to let it disappear only after no bfq_queue refers to it
any longer.

This commit also removes or updates some stale comments on locking
issues related to blk-cgroup operations.

Reported-by: Tomas Konir <tomas.konir@gmail.com>
Reported-by: Lee Tibbert <lee.tibbert@gmail.com>
Reported-by: Marco Piazza <mpiazza@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Tested-by: Tomas Konir <tomas.konir@gmail.com>
Tested-by: Lee Tibbert <lee.tibbert@gmail.com>
Tested-by: Marco Piazza <mpiazza@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-08 09:51:10 -06:00
Shaohua Li
6679a90c4b blk-throttle: set default latency baseline for harddisk
hard disk IO latency varies a lot depending on spindle move. The latency
range could be from several microseconds to several milliseconds. It's
pretty hard to get the baseline latency used by io.low.

We will use a different stragety here. The idea is only using IO with
spindle move to determine if cgroup IO is in good state. For HD, if io
latency is small (< 1ms), we ignore the IO. Such IO is likely from
sequential IO, and is helpless to help determine if a cgroup's IO is
impacted by other cgroups. With this, we only account IO with big
latency. Then we can choose a hardcoded baseline latency for HD (4ms,
which is typical IO latency with seek).  With all these settings, the
io.low latency works for both HD and SSD.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-07 09:09:32 -06:00
Joseph Qi
a41b816c17 blk-throttle: fix NULL pointer dereference in throtl_schedule_pending_timer
I have encountered a NULL pointer dereference in
throtl_schedule_pending_timer:
  [  413.735396] BUG: unable to handle kernel NULL pointer dereference at 0000000000000038
  [  413.735535] IP: [<ffffffff812ebbbf>] throtl_schedule_pending_timer+0x3f/0x210
  [  413.735643] PGD 22c8cf067 PUD 22cb34067 PMD 0
  [  413.735713] Oops: 0000 [#1] SMP
  ......

This is caused by the following case:
  blk_throtl_bio
    throtl_schedule_next_dispatch  <= sq is top level one without parent
      throtl_schedule_pending_timer
        sq_to_tg(sq)->td->throtl_slice  <= sq_to_tg(sq) returns NULL

Fix it by using sq_to_td instead of sq_to_tg(sq)->td, which will always
return a valid td.

Fixes: 297e3d8547 ("blk-throttle: make throtl_slice tunable")
Signed-off-by: Joseph Qi <qijiang.qj@alibaba-inc.com>
Reviewed-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-07 08:11:24 -06:00
Ming Lei
d964f04a8f blk-mq: fix direct issue
If queue is stopped, we shouldn't dispatch request into driver and
hardware, unfortunately the check is removed in bd166ef183c2(blk-mq-sched:
add framework for MQ capable IO schedulers).

This patch fixes the issue by moving the check back into
__blk_mq_try_issue_directly().

This patch fixes request use-after-free[1][2] during canceling requets
of NVMe in nvme_dev_disable(), which can be triggered easily during
NVMe reset & remove test.

[1] oops kernel log when CONFIG_BLK_DEV_INTEGRITY is on
[  103.412969] BUG: unable to handle kernel NULL pointer dereference at 000000000000000a
[  103.412980] IP: bio_integrity_advance+0x48/0xf0
[  103.412981] PGD 275a88067
[  103.412981] P4D 275a88067
[  103.412982] PUD 276c43067
[  103.412983] PMD 0
[  103.412984]
[  103.412986] Oops: 0000 [#1] SMP
[  103.412989] Modules linked in: vfat fat intel_rapl sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel crypto_simd cryptd ipmi_ssif iTCO_wdt iTCO_vendor_support mxm_wmi glue_helper dcdbas ipmi_si mei_me pcspkr mei sg ipmi_devintf lpc_ich ipmi_msghandler shpchp acpi_power_meter wmi nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod mgag200 i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm crc32c_intel nvme ahci nvme_core libahci libata tg3 i2c_core megaraid_sas ptp pps_core dm_mirror dm_region_hash dm_log dm_mod
[  103.413035] CPU: 0 PID: 102 Comm: kworker/0:2 Not tainted 4.11.0+ #1
[  103.413036] Hardware name: Dell Inc. PowerEdge R730xd/072T6D, BIOS 2.2.5 09/06/2016
[  103.413041] Workqueue: events nvme_remove_dead_ctrl_work [nvme]
[  103.413043] task: ffff9cc8775c8000 task.stack: ffffc033c252c000
[  103.413045] RIP: 0010:bio_integrity_advance+0x48/0xf0
[  103.413046] RSP: 0018:ffffc033c252fc10 EFLAGS: 00010202
[  103.413048] RAX: 0000000000000000 RBX: ffff9cc8720a8cc0 RCX: ffff9cca72958240
[  103.413049] RDX: ffff9cca72958000 RSI: 0000000000000008 RDI: ffff9cc872537f00
[  103.413049] RBP: ffffc033c252fc28 R08: 0000000000000000 R09: ffffffffb963a0d5
[  103.413050] R10: 000000000000063e R11: 0000000000000000 R12: ffff9cc8720a8d18
[  103.413051] R13: 0000000000001000 R14: ffff9cc872682e00 R15: 00000000fffffffb
[  103.413053] FS:  0000000000000000(0000) GS:ffff9cc877c00000(0000) knlGS:0000000000000000
[  103.413054] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  103.413055] CR2: 000000000000000a CR3: 0000000276c41000 CR4: 00000000001406f0
[  103.413056] Call Trace:
[  103.413063]  bio_advance+0x2a/0xe0
[  103.413067]  blk_update_request+0x76/0x330
[  103.413072]  blk_mq_end_request+0x1a/0x70
[  103.413074]  blk_mq_dispatch_rq_list+0x370/0x410
[  103.413076]  ? blk_mq_flush_busy_ctxs+0x94/0xe0
[  103.413080]  blk_mq_sched_dispatch_requests+0x173/0x1a0
[  103.413083]  __blk_mq_run_hw_queue+0x8e/0xa0
[  103.413085]  __blk_mq_delay_run_hw_queue+0x9d/0xa0
[  103.413088]  blk_mq_start_hw_queue+0x17/0x20
[  103.413090]  blk_mq_start_hw_queues+0x32/0x50
[  103.413095]  nvme_kill_queues+0x54/0x80 [nvme_core]
[  103.413097]  nvme_remove_dead_ctrl_work+0x1f/0x40 [nvme]
[  103.413103]  process_one_work+0x149/0x360
[  103.413105]  worker_thread+0x4d/0x3c0
[  103.413109]  kthread+0x109/0x140
[  103.413111]  ? rescuer_thread+0x380/0x380
[  103.413113]  ? kthread_park+0x60/0x60
[  103.413120]  ret_from_fork+0x2c/0x40
[  103.413121] Code: 08 4c 8b 63 50 48 8b 80 80 00 00 00 48 8b 90 d0 03 00 00 31 c0 48 83 ba 40 02 00 00 00 48 8d 8a 40 02 00 00 48 0f 45 c1 c1 ee 09 <0f> b6 48 0a 0f b6 40 09 41 89 f5 83 e9 09 41 d3 ed 44 0f af e8
[  103.413145] RIP: bio_integrity_advance+0x48/0xf0 RSP: ffffc033c252fc10
[  103.413146] CR2: 000000000000000a
[  103.413157] ---[ end trace cd6875d16eb5a11e ]---
[  103.455368] Kernel panic - not syncing: Fatal exception
[  103.459826] Kernel Offset: 0x37600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[  103.850916] ---[ end Kernel panic - not syncing: Fatal exception
[  103.857637] sched: Unexpected reschedule of offline CPU#1!
[  103.863762] ------------[ cut here ]------------

[2] kernel hang in blk_mq_freeze_queue_wait() when CONFIG_BLK_DEV_INTEGRITY is off
[  247.129825] INFO: task nvme-test:1772 blocked for more than 120 seconds.
[  247.137311]       Not tainted 4.12.0-rc2.upstream+ #4
[  247.142954] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  247.151704] Call Trace:
[  247.154445]  __schedule+0x28a/0x880
[  247.158341]  schedule+0x36/0x80
[  247.161850]  blk_mq_freeze_queue_wait+0x4b/0xb0
[  247.166913]  ? remove_wait_queue+0x60/0x60
[  247.171485]  blk_freeze_queue+0x1a/0x20
[  247.175770]  blk_cleanup_queue+0x7f/0x140
[  247.180252]  nvme_ns_remove+0xa3/0xb0 [nvme_core]
[  247.185503]  nvme_remove_namespaces+0x32/0x50 [nvme_core]
[  247.191532]  nvme_uninit_ctrl+0x2d/0xa0 [nvme_core]
[  247.196977]  nvme_remove+0x70/0x110 [nvme]
[  247.201545]  pci_device_remove+0x39/0xc0
[  247.205927]  device_release_driver_internal+0x141/0x200
[  247.211761]  device_release_driver+0x12/0x20
[  247.216531]  pci_stop_bus_device+0x8c/0xa0
[  247.221104]  pci_stop_and_remove_bus_device_locked+0x1a/0x30
[  247.227420]  remove_store+0x7c/0x90
[  247.231320]  dev_attr_store+0x18/0x30
[  247.235409]  sysfs_kf_write+0x3a/0x50
[  247.239497]  kernfs_fop_write+0xff/0x180
[  247.243867]  __vfs_write+0x37/0x160
[  247.247757]  ? selinux_file_permission+0xe5/0x120
[  247.253011]  ? security_file_permission+0x3b/0xc0
[  247.258260]  vfs_write+0xb2/0x1b0
[  247.261964]  ? syscall_trace_enter+0x1d0/0x2b0
[  247.266924]  SyS_write+0x55/0xc0
[  247.270540]  do_syscall_64+0x67/0x150
[  247.274636]  entry_SYSCALL64_slow_path+0x25/0x25
[  247.279794] RIP: 0033:0x7f5c96740840
[  247.283785] RSP: 002b:00007ffd00e87ee8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  247.292238] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f5c96740840
[  247.300194] RDX: 0000000000000002 RSI: 00007f5c97060000 RDI: 0000000000000001
[  247.308159] RBP: 00007f5c97060000 R08: 000000000000000a R09: 00007f5c97059740
[  247.316123] R10: 0000000000000001 R11: 0000000000000246 R12: 00007f5c96a14400
[  247.324087] R13: 0000000000000002 R14: 0000000000000001 R15: 0000000000000000
[  370.016340] INFO: task nvme-test:1772 blocked for more than 120 seconds.

Fixes: 12d70958a2e8(blk-mq: don't fail allocating driver tag for stopped hw queue)
Cc: stable@vger.kernel.org
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-06 10:00:35 -06:00
Ming Lei
dad7a3be49 blk-mq: pass correct hctx to blk_mq_try_issue_directly
When direct issue is done on request picked up from plug list,
the hctx need to be updated with the actual hw queue, otherwise
wrong hctx is used and may hurt performance, especially when
wrong SRCU readlock is acquired/released

Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-06 10:00:33 -06:00
Christoph Hellwig
59b9c6291c partitions/ldm: switch to use uuid_t
And the uuid helpers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:14 +02:00
Dmitry Monakhov
3116a23bb3 bio-integrity: Do not allocate integrity context for bio w/o data
If bio has no data, such as ones from blkdev_issue_flush(),
then we have nothing to protect.

This patch prevent bugon like follows:

kfree_debugcheck: out of range ptr ac1fa1d106742a5ah
kernel BUG at mm/slab.c:2773!
invalid opcode: 0000 [#1] SMP
Modules linked in: bcache
CPU: 0 PID: 4428 Comm: xfs_io Tainted: G        W       4.11.0-rc4-ext4-00041-g2ef0043-dirty #43
Hardware name: Virtuozzo KVM, BIOS seabios-1.7.5-11.vz7.4 04/01/2014
task: ffff880137786440 task.stack: ffffc90000ba8000
RIP: 0010:kfree_debugcheck+0x25/0x2a
RSP: 0018:ffffc90000babde0 EFLAGS: 00010082
RAX: 0000000000000034 RBX: ac1fa1d106742a5a RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88013f3ccb40
RBP: ffffc90000babde8 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000fcb76420 R11: 00000000725172ed R12: 0000000000000282
R13: ffffffff8150e766 R14: ffff88013a145e00 R15: 0000000000000001
FS:  00007fb09384bf40(0000) GS:ffff88013f200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0172f9e40 CR3: 0000000137fa9000 CR4: 00000000000006f0
Call Trace:
 kfree+0xc8/0x1b3
 bio_integrity_free+0xc3/0x16b
 bio_free+0x25/0x66
 bio_put+0x14/0x26
 blkdev_issue_flush+0x7a/0x85
 blkdev_fsync+0x35/0x42
 vfs_fsync_range+0x8e/0x9f
 vfs_fsync+0x1c/0x1e
 do_fsync+0x31/0x4a
 SyS_fsync+0x10/0x14
 entry_SYSCALL_64_fastpath+0x1f/0xc2

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-03 07:36:27 -06:00
Bart Van Assche
d9f9726446 bsg: Check queue type before attaching to a queue
Since BSG only supports request queues for which struct scsi_request
is the first member of their private request data, refuse to register
block layer queues for which struct scsi_request is not the first
member of their private data.

References: commit bd1599d931 ("scsi_transport_sas: fix BSG ioctl memory corruption")
References: commit 82ed4db499 ("block: split scsi_request out of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-01 13:10:41 -06:00
Bart Van Assche
9efc160f4b block: Introduce queue flag QUEUE_FLAG_SCSI_PASSTHROUGH
From the context where a SCSI command is submitted it is not always
possible to figure out whether or not the queue the command is
submitted to has struct scsi_request as the first member of its
private data. Hence introduce the flag QUEUE_FLAG_SCSI_PASSTHROUGH.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Don Brace <don.brace@microsemi.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-01 13:10:40 -06:00
Bart Van Assche
b425e50492 block: Avoid that blk_exit_rl() triggers a use-after-free
Since the introduction of .init_rq_fn() and .exit_rq_fn() it is
essential that the memory allocated for struct request_queue
stays around until all blk_exit_rl() calls have finished. Hence
make blk_init_rl() take a reference on struct request_queue.

This patch fixes the following crash:

general protection fault: 0000 [#2] SMP
CPU: 3 PID: 28 Comm: ksoftirqd/3 Tainted: G      D         4.12.0-rc2-dbg+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
task: ffff88013a108040 task.stack: ffffc9000071c000
RIP: 0010:free_request_size+0x1a/0x30
RSP: 0018:ffffc9000071fd38 EFLAGS: 00010202
RAX: 6b6b6b6b6b6b6b6b RBX: ffff880067362a88 RCX: 0000000000000003
RDX: ffff880067464178 RSI: ffff880067362a88 RDI: ffff880135ea4418
RBP: ffffc9000071fd40 R08: 0000000000000000 R09: 0000000100180009
R10: ffffc9000071fd38 R11: ffffffff81110800 R12: ffff88006752d3d8
R13: ffff88006752d3d8 R14: ffff88013a108040 R15: 000000000000000a
FS:  0000000000000000(0000) GS:ffff88013fd80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa8ec1edb00 CR3: 0000000138ee8000 CR4: 00000000001406e0
Call Trace:
 mempool_destroy.part.10+0x21/0x40
 mempool_destroy+0xe/0x10
 blk_exit_rl+0x12/0x20
 blkg_free+0x4d/0xa0
 __blkg_release_rcu+0x59/0x170
 rcu_process_callbacks+0x260/0x4e0
 __do_softirq+0x116/0x250
 smpboot_thread_fn+0x123/0x1e0
 kthread+0x109/0x140
 ret_from_fork+0x31/0x40

Fixes: commit e9c787e65c ("scsi: allocate scsi_cmnd structures as part of struct request")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@vger.kernel.org> # v4.11+
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-01 13:07:55 -06:00
Bart Van Assche
edea55abb8 blk-mq-debugfs: Add 'kick' operation
Running a queue causes the block layer to examine the per-CPU and
hw queues but not the requeue list. Hence add a 'kick' operation
that also examines the requeue list.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-01 13:03:00 -06:00
Bart Van Assche
2720bab502 blk-mq-debugfs: Show busy requests
Requests that got stuck in a block driver are neither on
blk_mq_ctx.rq_list nor on any hw dispatch queue. Make these
visible in debugfs through the "busy" attribute.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-01 13:02:59 -06:00
Bart Van Assche
8ef1a19103 blk-mq-debugfs: Show requeue list
When verifying whether or not a blk-mq driver forgot to kick the
requeue list after having requeued a request it is important to
be able to verify the contents of the requeue list. Hence export
that list through debugfs.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-01 13:02:58 -06:00
Bart Van Assche
c0cb1c6d39 blk-mq-debugfs: Show atomic request flags
When analyzing e.g. queue lockups it is important to know whether
or not a request has already been started. Hence also show the
atomic request flags.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Eduardo Valentin <eduval@amazon.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-01 13:02:56 -06:00
Hou Tao
5be6b75610 cfq-iosched: fix the delay of cfq_group's vdisktime under iops mode
When adding a cfq_group into the cfq service tree, we use CFQ_IDLE_DELAY
as the delay of cfq_group's vdisktime if there have been other cfq_groups
already.

When cfq is under iops mode, commit 9a7f38c42c ("cfq-iosched: Convert
from jiffies to nanoseconds") could result in a large iops delay and
lead to an abnormal io schedule delay for the added cfq_group. To fix
it, we just need to revert to the old CFQ_IDLE_DELAY value: HZ / 5
when iops mode is enabled.

Despite having the same value, the delay of a cfq_queue in idle class
and the delay of cfq_group are different things, so I define two new
macros for the delay of a cfq_group under time-slice mode and iops mode.

Fixes: 9a7f38c42c ("cfq-iosched: Convert from jiffies to nanoseconds")
Cc: <stable@vger.kernel.org> # 4.8+
Signed-off-by: Hou Tao <houtao1@huawei.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-31 09:25:21 -06:00
Keith Busch
e4dc2b32df blk-mq: Take tagset lock when updating hw queues
The tagset lock needs to be held when iterating the tag_list, so a
lockdep assert was added when updating number of hardware queues. The
drivers calling this API, however, were unaware of the new requirement,
so are failing the assertion.

This patch takes the lock within the blk-mq function so the drivers do
not have to be modified in order to be safe.

Fixes: 705cda97e ("blk-mq: Make it safe to use RCU to iterate over blk_mq_tag_set.tag_list")
Reported-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-30 12:32:37 -06:00
Matthias Kaehlcke
03ea8ad78c cfq-iosched: Delete unused function min_vdisktime()
This fixes the following warning when building with clang:

    block/cfq-iosched.c:970:19: error: unused function 'min_vdisktime'
        [-Werror,-Wunused-function]

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-30 09:49:44 -06:00
Ming Lei
9bddeb2a5b blk-mq: make per-sw-queue bio merge as default .bio_merge
Because what the per-sw-queue bio merge does is basically same with
scheduler's .bio_merge(), this patch makes per-sw-queue bio merge
as the default .bio_merge if no scheduler is used or io scheduler
doesn't provide .bio_merge().

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-26 14:12:04 -06:00
Ming Lei
ab42f35d9c blk-mq: merge bio into sw queue before plugging
Before blk-mq is introduced, I/O is merged to elevator
before being putted into plug queue, but blk-mq changed the
order and makes merging to sw queue basically impossible.
Then it is observed that throughput of sequential I/O is degraded
about 10%~20% on virtio-blk in the test[1] if mq-deadline isn't used.

This patch moves the bio merging per sw queue before plugging,
like what blk_queue_bio() does, and the performance regression is
fixed under this situation.

[1]. test script:
sudo fio --direct=1 --size=128G --bsrange=4k-4k --runtime=40 --numjobs=16 --ioengine=libaio --iodepth=64 --group_reporting=1 --filename=/dev/vdb --name=virtio_blk-test-$RW --rw=$RW --output-format=json

RW=read or write

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-26 14:12:03 -06:00
Jens Axboe
8aa6382907 Merge branch 'nvme-4.12' of git://git.infradead.org/nvme into for-linus
Christoph writes:

"A couple of fixes for the next rc on the nvme front. Various FC fixes
from James, controller removal fixes from Ming (including a block layer
patch), a APST related device quirk from Andy, a RDMA fix for small
queue depth device from Marta, as well as fixes for the lack of
metadata support in non-PCIe drivers and the printk logging format from
me."
2017-05-26 09:11:19 -06:00
Bart Van Assche
a8ecdd7117 blk-mq: Only register debugfs attributes for blk-mq queues
The code in blk-mq-debugfs.c assumes that it is working on a blk-mq
queue and is not intended to work on a blk-sq queue. Hence only
register blk-mq debugfs attributes for blk-mq queues.

Fixes: commit 9c1051aacd ("blk-mq: untangle debugfs and sysfs")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-26 07:25:13 -06:00
Richard
223220356d partitions/msdos: FreeBSD UFS2 file systems are not recognized
The code in block/partitions/msdos.c recognizes FreeBSD, OpenBSD
and NetBSD partitions and does a reasonable job picking out OpenBSD
and NetBSD UFS subpartitions.

But for FreeBSD the subpartitions are always "bad".

    Kernel: <bsd:bad subpartition - ignored

Though all 3 of these BSD systems use UFS as a file system, only
FreeBSD uses relative start addresses in the subpartition
declarations.

The following patch fixes this for FreeBSD partitions and leaves
the code for OpenBSD and NetBSD intact:

Signed-off-by: Richard Narron <comet.berkeley@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-23 09:16:07 -06:00
Dan Carpenter
7bd897cfce block: fix an error code in add_partition()
We don't set an error code on this path.  It means that we return NULL
instead of an error pointer and the caller does a NULL dereference.

Fixes: 6d1d8050b4 ("block, partition: add partition_meta_info to hd_struct")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-23 08:41:59 -06:00
Shaohua Li
b4f428ef28 blk-throttle: force user to configure all settings for io.low
Default value of io.low limit is 0. If user doesn't configure the limit,
last patch makes cgroup be throttled to very tiny bps/iops, which could
stall the system. A cgroup with default settings of io.low limit really
means nothing, so we force user to configure all settings, otherwise
io.low limit doesn't take effect. With this stragety, default setting of
latency/idle isn't important, so just set them to very conservative and
safe value.

Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-22 14:47:12 -06:00
Shaohua Li
9bb67aeb96 blk-throttle: respect 0 bps/iops settings for io.low
If a cgroup with low limit 0 for both bps/iops, the cgroup's low limit
is ignored and we throttle the cgroup with its max limit. In this way,
other cgroups with a low limit will not get protected. To fix this, we
don't do the exception any more. cgroup will be throttled to a limit 0
if it uese default setting. To avoid completed stall, we give such
cgroup tiny IO resources.

Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-22 14:47:12 -06:00
Shaohua Li
4cff729f62 blk-throttle: output some debug info in trace
These info are important to understand what's happening and help debug.

Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-22 14:47:12 -06:00
Shaohua Li
5b81fc3cc6 blk-throttle: add hierarchy support for latency target and idle time
For idle time, children's setting should not be bigger than parent's.
For latency target, children's setting should not be smaller than
parent's. The leaf nodes will adjust their settings according to the
hierarchy and compare their IO with the settings and do
upgrade/downgrade. parents nodes don't need to track their IO
latency/idle time.

Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-22 14:47:12 -06:00
Ming Lei
7254a50a5d blk-mq: remove blk_mq_abort_requeue_list()
No one uses it any more, so remove it.

Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-05-22 20:50:11 +02:00
Linus Torvalds
0fcc3ab23d Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
 "Incremental fixes and a small feature addition on top of the main
  libnvdimm 4.12 pull request:

   - Geert noticed that tinyconfig was bloated by BLOCK selecting DAX.
     The size regression is fixed by moving all dax helpers into the
     dax-core and only specifying "select DAX" for FS_DAX and
     dax-capable drivers. He also asked for clarification of the
     NR_DEV_DAX config option which, on closer look, does not need to be
     a config option at all. Mike also throws in a DEV_DAX_PMEM fixup
     for good measure.

   - Ben's attention to detail on -stable patch submissions caught a
     case where the recent fixes to arch_copy_from_iter_pmem() missed a
     condition where we strand dirty data in the cache. This is tagged
     for -stable and will also be included in the rework of the pmem api
     to a proposed {memcpy,copy_user}_flushcache() interface for 4.13.

   - Vishal adds a feature that missed the initial pull due to pending
     review feedback. It allows the kernel to clear media errors when
     initializing a BTT (atomic sector update driver) instance on a pmem
     namespace.

   - Ross noticed that the dax_device + dax_operations conversion broke
     __dax_zero_page_range(). The nvdimm unit tests fail to check this
     path, but xfstests immediately trips over it. No excuse for missing
     this before submitting the 4.12 pull request.

  These all pass the nvdimm unit tests and an xfstests spot check. The
  set has received a build success notification from the kbuild robot"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  filesystem-dax: fix broken __dax_zero_page_range() conversion
  libnvdimm, btt: ensure that initializing metadata clears poison
  libnvdimm: add an atomic vs process context flag to rw_bytes
  x86, pmem: Fix cache flushing for iovec write < 8 bytes
  device-dax: kill NR_DEV_DAX
  block, dax: move "select DAX" from BLOCK to FS_DAX
  device-dax: Tell kbuild DEV_DAX_PMEM depends on DEV_DAX
2017-05-12 15:43:10 -07:00
Christoph Hellwig
ed6565e734 block: handle partial completions for special payload requests
SCSI devices can return short writes on Write Same just like for normal
writes, so we need to handle this case for our special payload requests
as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Tested-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-11 08:08:53 -06:00
Wen Xiong
f36ea50ca0 blk-mq: NVMe 512B/4K+T10 DIF/DIX format returns I/O error on dd with split op
When formatting NVMe to 512B/4K + T10 DIf/DIX, dd with split op returns
"Input/output error". Looks block layer split the bio after calling
bio_integrity_prep(bio). This patch fixes the issue.

Below is how we debug this issue:
(1)format nvme to 4K block # size with type 2 DIF
(2)dd with block size bigger than 1024k.
oflag=direct
dd: error writing '/dev/nvme0n1': Input/output error

We added some debug code in nvme device driver. It showed us the first
op and the second op have the same bi and pi address. This is not
correct.

1st op: nvme0n1 Op:Wr slba 0x505 length 0x100, PI ctrl=0x1400,
	dsmgmt=0x0, AT=0x0 & RT=0x505
	Guard 0x00b1, AT 0x0000, RT physical 0x00000505 RT virtual 0x00002828

2nd op: nvme0n1 Op:Wr slba 0x605 length 0x1, PI ctrl=0x1400, dsmgmt=0x0,
	AT=0x0 & RT=0x605  ==> This op fails and subsequent 5 retires..
	Guard 0x00b1, AT 0x0000, RT physical 0x00000605 RT virtual 0x00002828

With the fix, It showed us both of the first op and the second op have
correct bi and pi address.

1st op: nvme2n1 Op:Wr slba 0x505 length 0x100, PI ctrl=0x1400,
	dsmgmt=0x0, AT=0x0 & RT=0x505
	Guard 0x5ccb, AT 0x0000, RT physical 0x00000505 RT virtual
	0x00002828
2nd op: nvme2n1 Op:Wr slba 0x605 length 0x1, PI ctrl=0x1400, dsmgmt=0x0,
	AT=0x0 & RT=0x605
	Guard 0xab4c, AT 0x0000, RT physical 0x00000605 RT virtual
	0x00003028

Signed-off-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-10 08:02:58 -06:00
Jens Axboe
d373812398 blk-stat: don't use this_cpu_ptr() in a preemptable section
If PREEMPT_RCU is enabled, rcu_read_lock() isn't strong enough
for us to use this_cpu_ptr() in that section. Use the safer
get/put_cpu_ptr() variants instead.

Reported-by: Mike Galbraith <efault@gmx.de>
Fixes: 34dbad5d26 ("blk-stat: convert to callback-based statistics reporting")
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-10 07:40:18 -06:00
Jens Axboe
340ff32167 elevator: remove redundant warnings on IO scheduler switch
We warn twice for switching to a scheduler, if that switch fails.
As we also report the failure in the return value to the
sysfs write, remove the dmesg induced failures.

Keep the failure print for warning to switch to the kconfig
selected IO scheduler, as we can't report errors for that in
any other way.

Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-10 07:40:04 -06:00
Paolo Valente
43c1b3d6e5 block, bfq: stress that low_latency must be off to get max throughput
The introduction of the BFQ and Kyber I/O schedulers has triggered a
new wave of I/O benchmarks. Unfortunately, comments and discussions on
these benchmarks confirm that there is still little awareness that it
is very hard to achieve, at the same time, a low latency and a high
throughput. In particular, virtually all benchmarks measure
throughput, or throughput-related figures of merit, but, for BFQ, they
use the scheduler in its default configuration. This configuration is
geared, instead, toward a low latency. This is evidently a sign that
BFQ documentation is still too unclear on this important aspect. This
commit addresses this issue by stressing how BFQ configuration must be
(easily) changed if the only goal is maximum throughput.

Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-10 07:39:43 -06:00
Paolo Valente
a66c38a171 block, bfq: use pointer entity->sched_data only if set
In the function __bfq_deactivate_entity, the pointer
entity->sched_data could happen to be used before being properly
initialized. This led to a NULL pointer dereference. This commit fixes
this bug by just using this pointer only where it is safe to do so.

Reported-by: Tom Harrison <l12436.tw@gmail.com>
Tested-by: Tom Harrison <l12436.tw@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-10 07:39:43 -06:00
Dan Williams
ef51042472 block, dax: move "select DAX" from BLOCK to FS_DAX
For configurations that do not enable DAX filesystems or drivers, do not
require the DAX core to be built.

Given that the 'direct_access' method has been removed from
'block_device_operations', we can also go ahead and remove the
block-related dax helper functions from fs/block_dev.c to
drivers/dax/super.c. This keeps dax details out of the block layer and
lets the DAX core be built as a module in the FS_DAX=n case.

Filesystems need to include dax.h to call bdev_dax_supported().

Cc: linux-xfs@vger.kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-05-08 10:55:27 -07:00
Colin Ian King
ebd7685795 blk-mq: make __blk_mq_stop_hw_queues static
Making __blk_mq_stop_hw_queues static fixes sparse warning:

  block/blk-mq.c:6: warning: symbol '__blk_mq_stop_hw_queues' was not
  declared. Should it be static?

Fixes: 2719aa217e ("blk-mq: don't use sync workqueue flushing from drivers")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-08 08:09:39 -06:00
Wanpeng Li
51d638b1f5 block/mq: fix potential deadlock during cpu hotplug
This can be triggered by hot-unplug one cpu.

======================================================
 [ INFO: possible circular locking dependency detected ]
 4.11.0+ #17 Not tainted
 -------------------------------------------------------
 step_after_susp/2640 is trying to acquire lock:
  (all_q_mutex){+.+...}, at: [<ffffffffb33f95b8>] blk_mq_queue_reinit_work+0x18/0x110

 but task is already holding lock:
  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffffb306d04f>] cpu_hotplug_begin+0x7f/0xe0

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (cpu_hotplug.lock){+.+.+.}:
        lock_acquire+0x11c/0x230
        __mutex_lock+0x92/0x990
        mutex_lock_nested+0x1b/0x20
        get_online_cpus+0x64/0x80
        blk_mq_init_allocated_queue+0x3a0/0x4e0
        blk_mq_init_queue+0x3a/0x60
        loop_add+0xe5/0x280
        loop_init+0x124/0x177
        do_one_initcall+0x53/0x1c0
        kernel_init_freeable+0x1e3/0x27f
        kernel_init+0xe/0x100
        ret_from_fork+0x31/0x40

 -> #0 (all_q_mutex){+.+...}:
        __lock_acquire+0x189a/0x18a0
        lock_acquire+0x11c/0x230
        __mutex_lock+0x92/0x990
        mutex_lock_nested+0x1b/0x20
        blk_mq_queue_reinit_work+0x18/0x110
        blk_mq_queue_reinit_dead+0x1c/0x20
        cpuhp_invoke_callback+0x1f2/0x810
        cpuhp_down_callbacks+0x42/0x80
        _cpu_down+0xb2/0xe0
        freeze_secondary_cpus+0xb6/0x390
        suspend_devices_and_enter+0x3b3/0xa40
        pm_suspend+0x129/0x490
        state_store+0x82/0xf0
        kobj_attr_store+0xf/0x20
        sysfs_kf_write+0x45/0x60
        kernfs_fop_write+0x135/0x1c0
        __vfs_write+0x37/0x160
        vfs_write+0xcd/0x1d0
        SyS_write+0x58/0xc0
        do_syscall_64+0x8f/0x710
        return_from_SYSCALL_64+0x0/0x7a

 other info that might help us debug this:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(cpu_hotplug.lock);
                                lock(all_q_mutex);
                                lock(cpu_hotplug.lock);
   lock(all_q_mutex);

  *** DEADLOCK ***

 8 locks held by step_after_susp/2640:
  #0:  (sb_writers#6){.+.+.+}, at: [<ffffffffb3244aed>] vfs_write+0x1ad/0x1d0
  #1:  (&of->mutex){+.+.+.}, at: [<ffffffffb32d3a51>] kernfs_fop_write+0x101/0x1c0
  #2:  (s_active#166){.+.+.+}, at: [<ffffffffb32d3a59>] kernfs_fop_write+0x109/0x1c0
  #3:  (pm_mutex){+.+...}, at: [<ffffffffb30d2ecd>] pm_suspend+0x21d/0x490
  #4:  (acpi_scan_lock){+.+.+.}, at: [<ffffffffb34dc3d7>] acpi_scan_lock_acquire+0x17/0x20
  #5:  (cpu_add_remove_lock){+.+.+.}, at: [<ffffffffb306d6d7>] freeze_secondary_cpus+0x27/0x390
  #6:  (cpu_hotplug.dep_map){++++++}, at: [<ffffffffb306cfd5>] cpu_hotplug_begin+0x5/0xe0
  #7:  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffffb306d04f>] cpu_hotplug_begin+0x7f/0xe0

 stack backtrace:
 CPU: 3 PID: 2640 Comm: step_after_susp Not tainted 4.11.0+ #17
 Hardware name: Dell Inc. OptiPlex 7040/0JCTF8, BIOS 1.4.9 09/12/2016
 Call Trace:
  dump_stack+0x99/0xce
  print_circular_bug+0x1fa/0x270
  __lock_acquire+0x189a/0x18a0
  lock_acquire+0x11c/0x230
  ? lock_acquire+0x11c/0x230
  ? blk_mq_queue_reinit_work+0x18/0x110
  ? blk_mq_queue_reinit_work+0x18/0x110
  __mutex_lock+0x92/0x990
  ? blk_mq_queue_reinit_work+0x18/0x110
  ? kmem_cache_free+0x2cb/0x330
  ? anon_transport_class_unregister+0x20/0x20
  ? blk_mq_queue_reinit_work+0x110/0x110
  mutex_lock_nested+0x1b/0x20
  ? mutex_lock_nested+0x1b/0x20
  blk_mq_queue_reinit_work+0x18/0x110
  blk_mq_queue_reinit_dead+0x1c/0x20
  cpuhp_invoke_callback+0x1f2/0x810
  ? __flow_cache_shrink+0x160/0x160
  cpuhp_down_callbacks+0x42/0x80
  _cpu_down+0xb2/0xe0
  freeze_secondary_cpus+0xb6/0x390
  suspend_devices_and_enter+0x3b3/0xa40
  ? rcu_read_lock_sched_held+0x79/0x80
  pm_suspend+0x129/0x490
  state_store+0x82/0xf0
  kobj_attr_store+0xf/0x20
  sysfs_kf_write+0x45/0x60
  kernfs_fop_write+0x135/0x1c0
  __vfs_write+0x37/0x160
  ? rcu_read_lock_sched_held+0x79/0x80
  ? rcu_sync_lockdep_assert+0x2f/0x60
  ? __sb_start_write+0xd9/0x1c0
  ? vfs_write+0x1ad/0x1d0
  vfs_write+0xcd/0x1d0
  SyS_write+0x58/0xc0
  ? rcu_read_lock_sched_held+0x79/0x80
  do_syscall_64+0x8f/0x710
  ? trace_hardirqs_on_thunk+0x1a/0x1c
  entry_SYSCALL64_slow_path+0x25/0x25

The cpu hotplug path will hold cpu_hotplug.lock and then reinit all exiting
queues for blk mq w/ all_q_mutex, however, blk_mq_init_allocated_queue() will
contend these two locks in the inversion order. This is due to commit eabe06595d
(blk/mq: Cure cpu hotplug lock inversion), it fixes a cpu hotplug lock inversion
issue because of hotplug rework, however the hotplug rework is still work-in-progress
and lives in a -tip branch and mainline cannot yet trigger that splat. The commit
breaks the linus's tree in the merge window, so this patch reverts the lock order
and avoids to splat linus's tree.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-07 19:50:11 -06:00
Linus Torvalds
044f1daaaa Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes and updates from Jens Axboe:
 "Some fixes and followup features/changes that should go in, in this
  merge window. This contains:

   - Two fixes for lightnvm from Javier, fixing problems in the new code
     merge previously in this merge window.

   - A fix from Jan for the backing device changes, fixing an issue in
     NFS that causes a failure to mount on certain setups.

   - A change from Christoph, cleaning up the blk-mq init and exit
     request paths.

   - Remove elevator_change(), which is now unused. From Bart.

   - A fix for queue operation invocation on a dead queue, from Bart.

   - A series fixing up mtip32xx for blk-mq scheduling, removing a
     bandaid we previously had in place for this. From me.

   - A regression fix for this series, fixing a case where we wait on
     workqueue flushing from an invalid (non-blocking) context. From me.

   - A fix/optimization from Ming, ensuring that we don't both quiesce
     and freeze a queue at the same time.

   - A fix from Peter on lock ordering for CPU hotplug. Not a real
     problem right now, but will be once the CPU hotplug rework goes in.

   - A series from Omar, cleaning up out blk-mq debugfs support, and
     adding support for exporting info from schedulers in debugfs as
     well. This is really useful in debugging stalls or livelocks. From
     Omar"

* 'for-linus' of git://git.kernel.dk/linux-block: (28 commits)
  mq-deadline: add debugfs attributes
  kyber: add debugfs attributes
  blk-mq-debugfs: allow schedulers to register debugfs attributes
  blk-mq: untangle debugfs and sysfs
  blk-mq: move debugfs declarations to a separate header file
  blk-mq: Do not invoke queue operations on a dead queue
  blk-mq-debugfs: get rid of a bunch of boilerplate
  blk-mq-debugfs: rename hw queue directories from <n> to hctx<n>
  blk-mq-debugfs: don't open code strstrip()
  blk-mq-debugfs: error on long write to queue "state" file
  blk-mq-debugfs: clean up flag definitions
  blk-mq-debugfs: separate flags with |
  nfs: Fix bdi handling for cloned superblocks
  block/mq: Cure cpu hotplug lock inversion
  lightnvm: fix bad back free on error path
  lightnvm: create cmd before allocating request
  blk-mq: don't use sync workqueue flushing from drivers
  mtip32xx: convert internal commands to regular block infrastructure
  mtip32xx: cleanup internal tag assumptions
  block: don't call blk_mq_quiesce_queue() after queue is frozen
  ...
2017-05-06 11:25:08 -07:00
Linus Torvalds
53ef7d0e20 libnvdimm for 4.12
* Region media error reporting: A libnvdimm region device is the parent
 to one or more namespaces. To date, media errors have been reported via
 the "badblocks" attribute attached to pmem block devices for namespaces
 in "raw" or "memory" mode. Given that namespaces can be in "device-dax"
 or "btt-sector" mode this new interface reports media errors
 generically, i.e. independent of namespace modes or state. This
 subsequently allows userspace tooling to craft "ACPI 6.1 Section
 9.20.7.6 Function Index 4 - Clear Uncorrectable Error" requests and
 submit them via the ioctl path for NVDIMM root bus devices.
 
 * Introduce 'struct dax_device' and 'struct dax_operations': Prompted by
 a request from Linus and feedback from Christoph this allows for dax
 capable drivers to publish their own custom dax operations. This fixes
 the broken assumption that all dax operations are related to a
 persistent memory device, and makes it easier for other architectures
 and platforms to add customized persistent memory support.
 
 * 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
 available for storage appliance applications to manually trigger memory
 controllers to drain write-pending buffers that would otherwise be
 flushed automatically by the platform ADR (asynchronous-DRAM-refresh)
 mechanism at a power loss event. Support for "locked" DIMMs is included
 to prevent namespaces from surfacing when the namespace label data area
 is locked. Finally, fixes for various reported deadlocks and crashes,
 also tagged for -stable.
 
 * ACPI / nfit driver updates: General updates of the nfit driver to add
 DSM command overrides, ACPI 6.1 health state flags support, DSM payload
 debug available by default, and various fixes.
 
 Acknowledgements that came after the branch was pushed:
 
 commmit 565851c972 "device-dax: fix sysfs attribute deadlock"
 Tested-by: Yi Zhang <yizhan@redhat.com>
 
 commit 23f4984483 "libnvdimm: rework region badblocks clearing"
 Tested-by: Toshi Kani <toshi.kani@hpe.com>
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZDONJAAoJEB7SkWpmfYgC3SsP/2KrLvTUcz646ViuPOgZ2cC4
 W6wAx6cvDSt+H52kLnFEsYoFt7WAj20ggPirb/Bc5jkGlvwE0lT9Xtmso9GpVkYT
 J9ZJ9pP/4YaAD3II1gmTwaUjYi0FxoOdx3Eb92yuWkO/8ylz4b2Nu3cBpYwyziGQ
 nIfEVwDXRLE86u6x0bWuf6TlVuvsbdiAI55CDqDMVQC6xIOLbSez7b8QIHlpiKEb
 Mw+xqdQva0esoreZEOXEhWNO+qtfILx8/ceBEGTNMp4e/JjZ2FbrSNplM+9bH5k7
 ywqP8lW+mBEw0fmBBkYoVG/xyesiiBb55JLnbi8Ew+7IUxw8a3iV7wftRi62lHcK
 zAjsHe4L+MansgtZsCL8wluvIPaktAdtB4xr7l9VNLKRYRUG73jEWU0gcUNryHIL
 BkQJ52pUS1PkClyAsWbBBHl1I/CvzVPd21VW0YELmLR4OywKy1c+eKw2bcYgjrb4
 59HZSv6S6EoKaQC+2qvVNpePil7cdfg5V2ubH/ki9HoYVyoxDptEWHnvf0NNatIH
 Y7mNcOPvhOksJmnKSyHbDjtRur7WoHIlC9D7UjEFkSBWsKPjxJHoidN4SnCMRtjQ
 WKQU0seoaKj04b68Bs/Qm9NozVgnsPFIUDZeLMikLFX2Jt7YSPu+Jmi2s4re6WLh
 TmJQ3Ly9t3o3/weHSzmn
 =Ox0s
 -----END PGP SIGNATURE-----

Merge tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "The bulk of this has been in multiple -next releases. There were a few
  late breaking fixes and small features that got added in the last
  couple days, but the whole set has received a build success
  notification from the kbuild robot.

  Change summary:

   - Region media error reporting: A libnvdimm region device is the
     parent to one or more namespaces. To date, media errors have been
     reported via the "badblocks" attribute attached to pmem block
     devices for namespaces in "raw" or "memory" mode. Given that
     namespaces can be in "device-dax" or "btt-sector" mode this new
     interface reports media errors generically, i.e. independent of
     namespace modes or state.

     This subsequently allows userspace tooling to craft "ACPI 6.1
     Section 9.20.7.6 Function Index 4 - Clear Uncorrectable Error"
     requests and submit them via the ioctl path for NVDIMM root bus
     devices.

   - Introduce 'struct dax_device' and 'struct dax_operations': Prompted
     by a request from Linus and feedback from Christoph this allows for
     dax capable drivers to publish their own custom dax operations.
     This fixes the broken assumption that all dax operations are
     related to a persistent memory device, and makes it easier for
     other architectures and platforms to add customized persistent
     memory support.

   - 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
     available for storage appliance applications to manually trigger
     memory controllers to drain write-pending buffers that would
     otherwise be flushed automatically by the platform ADR
     (asynchronous-DRAM-refresh) mechanism at a power loss event.
     Support for "locked" DIMMs is included to prevent namespaces from
     surfacing when the namespace label data area is locked. Finally,
     fixes for various reported deadlocks and crashes, also tagged for
     -stable.

   - ACPI / nfit driver updates: General updates of the nfit driver to
     add DSM command overrides, ACPI 6.1 health state flags support, DSM
     payload debug available by default, and various fixes.

  Acknowledgements that came after the branch was pushed:

   - commmit 565851c972 "device-dax: fix sysfs attribute deadlock":
     Tested-by: Yi Zhang <yizhan@redhat.com>

   - commit 23f4984483 "libnvdimm: rework region badblocks clearing"
     Tested-by: Toshi Kani <toshi.kani@hpe.com>"

* tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (52 commits)
  libnvdimm, pfn: fix 'npfns' vs section alignment
  libnvdimm: handle locked label storage areas
  libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
  brd: fix uninitialized use of brd->dax_dev
  block, dax: use correct format string in bdev_dax_supported
  device-dax: fix sysfs attribute deadlock
  libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking"
  libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
  libnvdimm: rework region badblocks clearing
  acpi, nfit: kill ACPI_NFIT_DEBUG
  libnvdimm: fix clear length of nvdimm_forget_poison()
  libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify
  libnvdimm, region: sysfs trigger for nvdimm_flush()
  libnvdimm: fix phys_addr for nvdimm_clear_poison
  x86, dax, pmem: remove indirection around memcpy_from_pmem()
  block: remove block_device_operations ->direct_access()
  block, dax: convert bdev_dax_supported() to dax_direct_access()
  filesystem-dax: convert to dax_direct_access()
  Revert "block: use DAX for partition table reads"
  ext2, ext4, xfs: retrieve dax_device for iomap operations
  ...
2017-05-05 18:49:20 -07:00
Omar Sandoval
daaadb3e94 mq-deadline: add debugfs attributes
Expose the fifo lists, cached next requests, batching state, and
dispatch list. It'd also be possible to add the sorted lists, but there
aren't already seq_file helpers for rbtrees.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:25:17 -06:00
Omar Sandoval
16b738f651 kyber: add debugfs attributes
Expose the domain token pools, asynchronous sbitmap depth, domain
request lists, and batching state.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:25:17 -06:00
Omar Sandoval
d332ce0918 blk-mq-debugfs: allow schedulers to register debugfs attributes
This provides the infrastructure for schedulers to expose their internal
state through debugfs. We add a list of queue attributes and a list of
hctx attributes to struct elevator_type and wire them up when switching
schedulers.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>

Add missing seq_file.h header in blk-mq-debugfs.h

Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:24:40 -06:00
Omar Sandoval
9c1051aacd blk-mq: untangle debugfs and sysfs
Originally, I tied debugfs registration/unregistration together with
sysfs. There's no reason to do this, and it's getting in the way of
letting schedulers define their own debugfs attributes. Instead, tie the
debugfs registration to the lifetime of the structures themselves.

The saner lifetimes mean we can also get rid of the extra mq directory
and move everything one level up. I.e., nvme0n1/mq/hctx0/tags is now
just nvme0n1/hctx0/tags.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:24:13 -06:00
Omar Sandoval
d173a25165 blk-mq: move debugfs declarations to a separate header file
Preparation for adding more declarations.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:23:44 -06:00
Bart Van Assche
18d4d7d057 blk-mq: Do not invoke queue operations on a dead queue
In commit e869b5462f ("blk-mq: Unregister debugfs attributes
earlier"), we shuffled the debugfs cleanup around so that the "state"
attribute was removed before we freed the blk-mq data structures.
However, later changes are going to undo that, so we need to explicitly
disallow running a dead queue.

[Omar: rebased and updated commit message]
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:23:39 -06:00
Omar Sandoval
f57de23ac9 blk-mq-debugfs: get rid of a bunch of boilerplate
A large part of blk-mq-debugfs.c is file_operations and seq_file
boilerplate. This sucks as is but will suck even more when schedulers
can define their own debugfs entries. Factor it all out into a single
blk_mq_debugfs_fops which multiplexes as needed. We store the
request_queue, blk_mq_hw_ctx, or blk_mq_ctx in the parent directory
dentry, which is kind of hacky, but it works.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:23:35 -06:00
Omar Sandoval
88aabbd7e7 blk-mq-debugfs: rename hw queue directories from <n> to hctx<n>
It's not clear what these numbered directories represent unless you
consult the code. We're about to get rid of the intermediate "mq"
directory, so these would be even more confusing without that context.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:23:30 -06:00
Omar Sandoval
71b90511cb blk-mq-debugfs: don't open code strstrip()
Slightly more readable, plus we also strip leading spaces.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:23:20 -06:00
Omar Sandoval
c7e4145ae1 blk-mq-debugfs: error on long write to queue "state" file
blk_queue_flags_store() currently truncates and returns a short write if
the operation being written is too long. This can give us weird results,
like here:

$ echo "run            bar"
echo: write error: invalid argument
$ dmesg
[ 1103.075435] blk_queue_flags_store: unsupported operation bar. Use either 'run' or 'start'

Instead, return an error if the user does this. While we're here, make
the argument names consistent with everywhere else in this file.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:23:16 -06:00
Omar Sandoval
1a435111f8 blk-mq-debugfs: clean up flag definitions
Make sure the spelled out flag names match the definition. This also
adds a missing hctx state, BLK_MQ_S_START_ON_RUN, and a missing
cmd_flag, __REQ_NOUNMAP.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:23:11 -06:00
Omar Sandoval
bec03d6b92 blk-mq-debugfs: separate flags with |
This reads more naturally than spaces.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 08:22:28 -06:00
Peter Zijlstra
eabe06595d block/mq: Cure cpu hotplug lock inversion
By poking at /debug/sched_features I triggered the following splat:

 [] ======================================================
 [] WARNING: possible circular locking dependency detected
 [] 4.11.0-00873-g964c8b7-dirty #694 Not tainted
 [] ------------------------------------------------------
 [] bash/2109 is trying to acquire lock:
 []  (cpu_hotplug_lock.rw_sem){++++++}, at: [<ffffffff8120cb8b>] static_key_slow_dec+0x1b/0x50
 []
 [] but task is already holding lock:
 []  (&sb->s_type->i_mutex_key#4){+++++.}, at: [<ffffffff81140216>] sched_feat_write+0x86/0x170
 []
 [] which lock already depends on the new lock.
 []
 []
 [] the existing dependency chain (in reverse order) is:
 []
 [] -> #2 (&sb->s_type->i_mutex_key#4){+++++.}:
 []        lock_acquire+0x100/0x210
 []        down_write+0x28/0x60
 []        start_creating+0x5e/0xf0
 []        debugfs_create_dir+0x13/0x110
 []        blk_mq_debugfs_register+0x21/0x70
 []        blk_mq_register_dev+0x64/0xd0
 []        blk_register_queue+0x6a/0x170
 []        device_add_disk+0x22d/0x440
 []        loop_add+0x1f3/0x280
 []        loop_init+0x104/0x142
 []        do_one_initcall+0x43/0x180
 []        kernel_init_freeable+0x1de/0x266
 []        kernel_init+0xe/0x100
 []        ret_from_fork+0x31/0x40
 []
 [] -> #1 (all_q_mutex){+.+.+.}:
 []        lock_acquire+0x100/0x210
 []        __mutex_lock+0x6c/0x960
 []        mutex_lock_nested+0x1b/0x20
 []        blk_mq_init_allocated_queue+0x37c/0x4e0
 []        blk_mq_init_queue+0x3a/0x60
 []        loop_add+0xe5/0x280
 []        loop_init+0x104/0x142
 []        do_one_initcall+0x43/0x180
 []        kernel_init_freeable+0x1de/0x266
 []        kernel_init+0xe/0x100
 []        ret_from_fork+0x31/0x40

 []  *** DEADLOCK ***
 []
 [] 3 locks held by bash/2109:
 []  #0:  (sb_writers#11){.+.+.+}, at: [<ffffffff81292bcd>] vfs_write+0x17d/0x1a0
 []  #1:  (debugfs_srcu){......}, at: [<ffffffff8155a90d>] full_proxy_write+0x5d/0xd0
 []  #2:  (&sb->s_type->i_mutex_key#4){+++++.}, at: [<ffffffff81140216>] sched_feat_write+0x86/0x170
 []
 [] stack backtrace:
 [] CPU: 9 PID: 2109 Comm: bash Not tainted 4.11.0-00873-g964c8b7-dirty #694
 [] Hardware name: Intel Corporation S2600GZ/S2600GZ, BIOS SE5C600.86B.02.02.0002.122320131210 12/23/2013
 [] Call Trace:

 []  lock_acquire+0x100/0x210
 []  get_online_cpus+0x2a/0x90
 []  static_key_slow_dec+0x1b/0x50
 []  static_key_disable+0x20/0x30
 []  sched_feat_write+0x131/0x170
 []  full_proxy_write+0x97/0xd0
 []  __vfs_write+0x28/0x120
 []  vfs_write+0xb5/0x1a0
 []  SyS_write+0x49/0xa0
 []  entry_SYSCALL_64_fastpath+0x23/0xc2

This is because of the cpu hotplug lock rework. Break the chain at #1
by reversing the lock acquisition order. This way i_mutex_key#4 no
longer depends on cpu_hotplug_lock and things are good.

Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-04 07:57:13 -06:00
Jens Axboe
2719aa217e blk-mq: don't use sync workqueue flushing from drivers
A previous commit introduced the sync flush, which we need from
internal callers like blk_mq_quiesce_queue(). However, we also
call the stop helpers from drivers, particularly from ->queue_rq()
when we have to stop processing for a bit. We can't block from
those locations, and we don't have to guarantee that we're
fully flushed.

Fixes: 9f99373790 ("blk-mq: unify hctx delayed_run_work and run_work")
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-03 11:44:43 -06:00
Linus Torvalds
e5021876c9 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md
Pull MD updates from Shaohua Li:

 - Add Partial Parity Log (ppl) feature found in Intel IMSM raid array
   by Artur Paszkiewicz. This feature is another way to close RAID5
   writehole. The Linux implementation is also available for normal
   RAID5 array if specific superblock bit is set.

 - A number of md-cluser fixes and enabling md-cluster array resize from
   Guoqing Jiang

 - A bunch of patches from Ming Lei and Neil Brown to rewrite MD bio
   handling related code. Now MD doesn't directly access bio bvec,
   bi_phys_segments and uses modern bio API for bio split.

 - Improve RAID5 IO pattern to improve performance for hard disk based
   RAID5/6 from me.

 - Several patches from Song Liu to speed up raid5-cache recovery and
   allow raid5 cache feature disabling in runtime.

 - Fix a performance regression in raid1 resync from Xiao Ni.

 - Other cleanup and fixes from various people.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: (84 commits)
  md/raid10: skip spare disk as 'first' disk
  md/raid1: Use a new variable to count flighting sync requests
  md: clear WantReplacement once disk is removed
  md/raid1/10: remove unused queue
  md: handle read-only member devices better.
  md/raid10: wait up frozen array in handle_write_completed
  uapi: fix linux/raid/md_p.h userspace compilation error
  md-cluster: Fix a memleak in an error handling path
  md: support disabling of create-on-open semantics.
  md: allow creation of mdNNN arrays via md_mod/parameters/new_array
  raid5-ppl: use a single mempool for ppl_io_unit and header_page
  md/raid0: fix up bio splitting.
  md/linear: improve bio splitting.
  md/raid5: make chunk_aligned_read() split bios more cleanly.
  md/raid10: simplify handle_read_error()
  md/raid10: simplify the splitting of requests.
  md/raid1: factor out flush_bio_list()
  md/raid1: simplify handle_read_error().
  Revert "block: introduce bio_copy_data_partial"
  md/raid1: simplify alloc_behind_master_bio()
  ...
2017-05-03 10:05:38 -07:00
Ming Lei
7a148c2fcf block: don't call blk_mq_quiesce_queue() after queue is frozen
After queue is frozen, no request in this queue can be in use at all, so
there can't be any .queue_rq() running on this queue.  It isn't
necessary to call blk_mq_quiesce_queue() any more, so remove it in both
elevator_switch_mq() and blk_mq_update_nr_requests().

Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>

Fixed up the description a bit.

Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-02 11:33:08 -06:00
Linus Torvalds
c58d4055c0 A reasonably busy cycle for documentation this time around. There is a new
guide for user-space API documents, rather sparsely populated at the
 moment, but it's a start.  Markus improved the infrastructure for
 converting diagrams.  Mauro has converted much of the USB documentation
 over to RST.  Plus the usual set of fixes, improvements, and tweaks.
 
 There's a bit more than the usual amount of reaching out of Documentation/
 to fix comments elsewhere in the tree; I have acks for those where I could
 get them.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZB1elAAoJEI3ONVYwIuV6wUIQAJSM/4rNdj6z+GXeWhRfbsOo
 vqqVYluvXQIJaaqdsy9dgcfThhOXWYsPyVF6Xd+bDJpwF3BMZYbX1CI1Mo3kRD+7
 9+Pf68cYSHRoU3l/sFI8q0zfKbHtmFteIvnRQoFtRaExqgTR8glUfxNDyN9XuNAZ
 3naS4qMZivM4gjMcSpIB/wFOQpV+6qVIs6VTFLdCC8wodT3W/Wmb+bqrCVJ0twbB
 t8jJeYHt2wsiTdqrKU+VilAUAZ1Lby+DNfeWrO18rC1ohktPyUzOGg8JmTKUBpVO
 qj1OJwD6abuaNh/J9bXsh8u0OrVrBKWjVrhq9IFYDlm92fu3Bgr6YeoaVPEpcklt
 jdlgZnWs9/oXa6d32aMc9F7mP9a0Q1qikFTYINhaHQZCb4VDRuQ9hCSuqWm5jlVy
 lmVAoxLa0zSdOoXaYuO3HC99ku1cIn814CXMDz/IwKXkqUCV+zl+H3AGkvxGyQ5M
 eblw2TnQnc6e1LRcxt5bgpFR1JYMbCJhu0U5XrNFueQV8ReB15dvL7h4y21dWJKF
 2Sr83rwfG1rpZQiSqCjOXxIzuXbEGH3+a+zCDV5IHhQRt/VNDOt2hgmcyucSSJ5h
 5GRFYgTlGvoT/6LdIT39QooHB+4tSDRtEQ6lh0q2ZtVV2rfG/I6/PR5sUbWM65SN
 vAfctRm2afHLhdonSX5O
 =41m+
 -----END PGP SIGNATURE-----

Merge tag 'docs-4.12' of git://git.lwn.net/linux

Pull documentation update from Jonathan Corbet:
 "A reasonably busy cycle for documentation this time around. There is a
  new guide for user-space API documents, rather sparsely populated at
  the moment, but it's a start. Markus improved the infrastructure for
  converting diagrams. Mauro has converted much of the USB documentation
  over to RST. Plus the usual set of fixes, improvements, and tweaks.

  There's a bit more than the usual amount of reaching out of
  Documentation/ to fix comments elsewhere in the tree; I have acks for
  those where I could get them"

* tag 'docs-4.12' of git://git.lwn.net/linux: (74 commits)
  docs: Fix a couple typos
  docs: Fix a spelling error in vfio-mediated-device.txt
  docs: Fix a spelling error in ioctl-number.txt
  MAINTAINERS: update file entry for HSI subsystem
  Documentation: allow installing man pages to a user defined directory
  Doc/PM: Sync with intel_powerclamp code behavior
  zr364xx.rst: usb/devices is now at /sys/kernel/debug/
  usb.rst: move documentation from proc_usb_info.txt to USB ReST book
  convert philips.txt to ReST and add to media docs
  docs-rst: usb: update old usbfs-related documentation
  arm: Documentation: update a path name
  docs: process/4.Coding.rst: Fix a couple of document refs
  docs-rst: fix usb cross-references
  usb: gadget.h: be consistent at kernel doc macros
  usb: composite.h: fix two warnings when building docs
  usb: get rid of some ReST doc build errors
  usb.rst: get rid of some Sphinx errors
  usb/URB.txt: convert to ReST and update it
  usb/persist.txt: convert to ReST and add to driver-api book
  usb/hotplug.txt: convert to ReST and add to driver-api book
  ...
2017-05-02 10:21:17 -07:00
Christoph Hellwig
d6296d39e9 blk-mq: update ->init_request and ->exit_request prototypes
Remove the request_idx parameter, which can't be used safely now that we
support I/O schedulers with blk-mq.  Except for a superflous check in
mtip32xx it was unused anyway.

Also pass the tag_set instead of just the driver data - this allows drivers
to avoid some code duplication in a follow on cleanup.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-02 07:52:08 -06:00
Jens Axboe
9f2779bff2 blk-mq-sched: remove hack that bypasses scheduler for reserved requests
We have update the troublesome driver (mtip32xx) to deal with this
appropriately. So kill the hack that bypassed scheduler allocation
and insertion for reserved requests.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-02 07:52:08 -06:00
Bart Van Assche
c033269490 block: Remove elevator_change()
Since commit 8425339492 ("remove the mg_disk driver") removed the
only caller of elevator_change(), also remove the elevator_change()
function itself.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-02 07:52:08 -06:00
Linus Torvalds
5db6db0d40 Merge branch 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uaccess unification updates from Al Viro:
 "This is the uaccess unification pile. It's _not_ the end of uaccess
  work, but the next batch of that will go into the next cycle. This one
  mostly takes copy_from_user() and friends out of arch/* and gets the
  zero-padding behaviour in sync for all architectures.

  Dealing with the nocache/writethrough mess is for the next cycle;
  fortunately, that's x86-only. Same for cleanups in iov_iter.c (I am
  sold on access_ok() in there, BTW; just not in this pile), same for
  reducing __copy_... callsites, strn*... stuff, etc. - there will be a
  pile about as large as this one in the next merge window.

  This one sat in -next for weeks. -3KLoC"

* 'work.uaccess' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (96 commits)
  HAVE_ARCH_HARDENED_USERCOPY is unconditional now
  CONFIG_ARCH_HAS_RAW_COPY_USER is unconditional now
  m32r: switch to RAW_COPY_USER
  hexagon: switch to RAW_COPY_USER
  microblaze: switch to RAW_COPY_USER
  get rid of padding, switch to RAW_COPY_USER
  ia64: get rid of copy_in_user()
  ia64: sanitize __access_ok()
  ia64: get rid of 'segment' argument of __do_{get,put}_user()
  ia64: get rid of 'segment' argument of __{get,put}_user_check()
  ia64: add extable.h
  powerpc: get rid of zeroing, switch to RAW_COPY_USER
  esas2r: don't open-code memdup_user()
  alpha: fix stack smashing in old_adjtimex(2)
  don't open-code kernel_setsockopt()
  mips: switch to RAW_COPY_USER
  mips: get rid of tail-zeroing in primitives
  mips: make copy_from_user() zero tail explicitly
  mips: clean and reorder the forest of macros...
  mips: consolidate __invoke_... wrappers
  ...
2017-05-01 14:41:04 -07:00
Shaohua Li
e265eb3a30 Merge branch 'md-next' into md-linus 2017-05-01 14:09:21 -07:00
Linus Torvalds
694752922b Merge branch 'for-4.12/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:

 - Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
   was initially a fork of CFQ, but subsequently changed to implement
   fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
   to be used on desktop type single drives, providing good fairness.
   From Paolo.

 - Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
   using a scalable token based algorithm that throttles IO based on
   live completion IO stats, similary to blk-wbt. From Omar.

 - A series from Jan, moving users to separately allocated backing
   devices. This continues the work of separating backing device life
   times, solving various problems with hot removal.

 - A series of updates for lightnvm, mostly from Javier. Includes a
   'pblk' target that exposes an open channel SSD as a physical block
   device.

 - A series of fixes and improvements for nbd from Josef.

 - A series from Omar, removing queue sharing between devices on mostly
   legacy drivers. This helps us clean up other bits, if we know that a
   queue only has a single device backing. This has been overdue for
   more than a decade.

 - Fixes for the blk-stats, and improvements to unify the stats and user
   windows. This both improves blk-wbt, and enables other users to
   register a need to receive IO stats for a device. From Omar.

 - blk-throttle improvements from Shaohua. This provides a scalable
   framework for implementing scalable priotization - particularly for
   blk-mq, but applicable to any type of block device. The interface is
   marked experimental for now.

 - Bucketized IO stats for IO polling from Stephen Bates. This improves
   efficiency of polled workloads in the presence of mixed block size
   IO.

 - A few fixes for opal, from Scott.

 - A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
   From a variety of folks, mostly Sagi and James Smart.

 - A series from Bart, improving our exposed info and capabilities from
   the blk-mq debugfs support.

 - A series from Christoph, cleaning up how handle WRITE_ZEROES.

 - A series from Christoph, cleaning up the block layer handling of how
   we track errors in a request. On top of being a nice cleanup, it also
   shrinks the size of struct request a bit.

 - Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
   never used by platforms, and the latter has outlived it's usefulness.

 - Various little bug fixes and cleanups from a wide variety of folks.

* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
  block: hide badblocks attribute by default
  blk-mq: unify hctx delay_work and run_work
  block: add kblock_mod_delayed_work_on()
  blk-mq: unify hctx delayed_run_work and run_work
  nbd: fix use after free on module unload
  MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
  blk-mq-sched: alloate reserved tags out of normal pool
  mtip32xx: use runtime tag to initialize command header
  scsi: Implement blk_mq_ops.show_rq()
  blk-mq: Add blk_mq_ops.show_rq()
  blk-mq: Show operation, cmd_flags and rq_flags names
  blk-mq: Make blk_flags_show() callers append a newline character
  blk-mq: Move the "state" debugfs attribute one level down
  blk-mq: Unregister debugfs attributes earlier
  blk-mq: Only unregister hctxs for which registration succeeded
  blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
  blk-mq: Let blk_mq_debugfs_register() look up the queue name
  blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
  ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
  ide-pm: always pass 0 error to __blk_end_request_all
  ..
2017-05-01 10:39:57 -07:00
Dan Williams
9438b3e080 block: hide badblocks attribute by default
Commit 99e6608c9e "block: Add badblock management for gendisks"
allowed for drivers like pmem and software-raid to advertise a list of
bad media areas. However, it inadvertently added a 'badblocks' to all
block devices. Lets clean this up by having the 'badblocks' attribute
not be visible when the driver has not populated a 'struct badblocks'
instance in the gendisk.

Cc: Jens Axboe <axboe@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-28 08:26:42 -06:00
Jens Axboe
21c6e939a9 blk-mq: unify hctx delay_work and run_work
The only difference between ->run_work and ->delay_work, is that
the latter is used to defer running a queue. This is done by
marking the queue stopped, and scheduling ->delay_work to run
sometime in the future. While the queue is stopped, direct runs
or runs through ->run_work will not run the queue.

If we combine the handlers, then we need to handle two things:

1) If a delayed/stopped run is scheduled, then we should not run
   the queue before that has been completed.
2) If a queue is delayed/stopped, the handler needs to restart
   the queue. Normally a run of a queue with the stopped bit set
   would be a no-op.

Case 1 is handled by modifying a currently pending queue run
to the deadline set by the caller of blk_mq_delay_queue().
Subsequent attempts to queue a queue run will find the work
item already pending, and direct runs will see a stopped queue
as before.

Case 2 is handled by adding a new bit, BLK_MQ_S_START_ON_RUN,
that tells the work handler that it should clear a stopped
queue and run the handler.

Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-28 08:11:43 -06:00
Jens Axboe
818cd1cbaa block: add kblock_mod_delayed_work_on()
This modifies (or adds, if not currently pending) an existing
delayed work item.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-28 08:10:15 -06:00
Jens Axboe
9f99373790 blk-mq: unify hctx delayed_run_work and run_work
They serve the exact same purpose. Get rid of the non-delayed
work variant, and just run it without delay for the normal case.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-28 08:10:15 -06:00
Jens Axboe
339318080b blk-mq-sched: alloate reserved tags out of normal pool
At least one driver, mtip32xx, has a hard coded dependency on
the value of the reserved tag used for internal commands. While
that should really be fixed up, for now let's ensure that we just
bypass the scheduler tags an allocation marked as reserved. They
are used for house keeping or error handling, so we can safely
ignore them in the scheduler.

Tested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-27 07:45:46 -06:00
Bart Van Assche
2836ee4b1a blk-mq: Add blk_mq_ops.show_rq()
This new callback function will be used in the next patch to show
more information about SCSI requests.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
8658dca8bd blk-mq: Show operation, cmd_flags and rq_flags names
Show the operation name, .cmd_flags and .rq_flags as names instead
of numbers.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
fd07dc8185 blk-mq: Make blk_flags_show() callers append a newline character
This patch does not change any functionality but makes it possible
to produce a single line of output with multiple flag-to-name
translations.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
65ca1ca32c blk-mq: Move the "state" debugfs attribute one level down
Move the "state" attribute from the top level to the "mq" directory
as requested by Omar.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
e869b5462f blk-mq: Unregister debugfs attributes earlier
We currently call blk_mq_free_queue() from blk_cleanup_queue()
before we unregister the debugfs attributes for that queue in
blk_release_queue(). This leaves a window open during which
accessing most of the mq debugfs attributes would cause a
use-after-free. Additionally, the "state" attribute allows
running the queue, which we should not do after the queue has
entered the "dead" state. Fix both cases by unregistering the
debugfs attributes before freeing queue resources starts.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
f05d1ba787 blk-mq: Only unregister hctxs for which registration succeeded
Hctx unregistration involves calling kobject_del(). kobject_del()
must not be called if kobject_add() has not been called. Hence in
the error path only unregister hctxs for which registration succeeded.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
62d6c9496a blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
Since the blk_mq_debugfs_*register_hctxs() functions register and
unregister all attributes under the "mq" directory, rename these
into blk_mq_debugfs_*register_mq().

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
4c9e4019f1 blk-mq: Let blk_mq_debugfs_register() look up the queue name
A later patch will move the call of blk_mq_debugfs_register() to
a function to which the queue name is not passed as an argument.
To avoid having to add a 'name' argument to multiple callers, let
blk_mq_debugfs_register() look up the queue name.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Bart Van Assche
2d0364c8c1 blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
A later patch in this series will modify blk_mq_debugfs_register()
such that it uses q->kobj.parent to determine the name of a
request queue. Hence make sure that that pointer is initialized
before blk_mq_debugfs_register() is called. To avoid lock inversion,
protect sysfs / debugfs registration with the queue sysfs_lock
instead of the global mutex all_q_mutex.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-26 15:09:04 -06:00
Dan Williams
a41fe02b6b Revert "block: use DAX for partition table reads"
commit d1a5f2b4d8 ("block: use DAX for partition table reads") was
part of a stalled effort to allow dax mappings of block devices. Since
then the device-dax mechanism has filled the role of dax-mapping static
device ranges.

Now that we are moving ->direct_access() from a block_device operation
to a dax_inode operation we would need block devices to map and carry
their own dax_inode reference.

Unless / until we decide to revive dax mapping of raw block devices
through the dax_inode scheme, there is no need to carry
read_dax_sector(). Its removal in turn allows for the removal of
bdev_direct_access() and should have been included in commit
2237570168 ("block_dev: remove DAX leftovers").

Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-25 13:20:46 -07:00
Mike Snitzer
2859323e35 block: fix blk_integrity_register to use template's interval_exp if not 0
When registering an integrity profile: if the template's interval_exp is
not 0 use it, otherwise use the ilog2() of logical block size of the
provided gendisk.

This fixes a long-standing DM linear target bug where it cannot pass
integrity data to the underlying device if its logical block size
conflicts with the underlying device's logical block size.

Cc: stable@vger.kernel.org
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-23 12:59:56 -06:00
Ilya Dryomov
19b7ccf865 block: get rid of blk_integrity_revalidate()
Commit 25520d55cd ("block: Inline blk_integrity in struct gendisk")
introduced blk_integrity_revalidate(), which seems to assume ownership
of the stable pages flag and unilaterally clears it if no blk_integrity
profile is registered:

    if (bi->profile)
            disk->queue->backing_dev_info->capabilities |=
                    BDI_CAP_STABLE_WRITES;
    else
            disk->queue->backing_dev_info->capabilities &=
                    ~BDI_CAP_STABLE_WRITES;

It's called from revalidate_disk() and rescan_partitions(), making it
impossible to enable stable pages for drivers that support partitions
and don't use blk_integrity: while the call in revalidate_disk() can be
trivially worked around (see zram, which doesn't support partitions and
hence gets away with zram_revalidate_disk()), rescan_partitions() can
be triggered from userspace at any time.  This breaks rbd, where the
ceph messenger is responsible for generating/verifying CRCs.

Since blk_integrity_{un,}register() "must" be used for (un)registering
the integrity profile with the block layer, move BDI_CAP_STABLE_WRITES
setting there.  This way drivers that call blk_integrity_register() and
use integrity infrastructure won't interfere with drivers that don't
but still want stable pages.

Fixes: 25520d55cd ("block: Inline blk_integrity in struct gendisk")
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 4.4+, needs backporting
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-21 14:17:27 -06:00
Bart Van Assche
abc25a6930 blk-mq: Fix preempt count imbalance
Avoid that the following kernel bug gets triggered:

BUG: sleeping function called from invalid context at ./include/linux/buffer_head.h:349
in_atomic(): 1, irqs_disabled(): 0, pid: 8019, name: find
CPU: 10 PID: 8019 Comm: find Tainted: G        W I     4.11.0-rc4-dbg+ #2
Call Trace:
 dump_stack+0x68/0x93
 ___might_sleep+0x16e/0x230
 __might_sleep+0x4a/0x80
 __ext4_get_inode_loc+0x1e0/0x4e0
 ext4_iget+0x70/0xbc0
 ext4_iget_normal+0x2f/0x40
 ext4_lookup+0xb6/0x1f0
 lookup_slow+0x104/0x1e0
 walk_component+0x19a/0x330
 path_lookupat+0x4b/0x100
 filename_lookup+0x9a/0x110
 user_path_at_empty+0x36/0x40
 vfs_statx+0x67/0xc0
 SYSC_newfstatat+0x20/0x40
 SyS_newfstatat+0xe/0x10
 entry_SYSCALL_64_fastpath+0x18/0xad

This happens since the big if/else in blk_mq_make_request() doesn't
have final else section that also drops the ctx. Add that.

Fixes: b00c53e8f4 ("blk-mq: fix schedule-while-atomic with scheduler attached")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Omar Sandoval <osandov@fb.com>

Added a bit more to the commit log.

Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-21 12:00:40 -06:00
Jens Axboe
99c749a4c4 blk-stat: kill blk_stat_rq_ddir()
No point in providing and exporting this helper. There's just
one (real) user of it, just use rq_data_dir().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-21 07:56:23 -06:00
Bart Van Assche
246665db3b blk-mq: Remove blk_mq_sched_move_to_dispatch()
commit c13660a08c ("blk-mq-sched: change ->dispatch_requests()
to ->dispatch_request()") removed the last user of this function.
Hence also remove the function itself.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 17:28:30 -06:00
Jens Axboe
5feeacdd4a blk-mq: add might_sleep check to blk_mq_get_driver_tag()
If the caller passes in wait=true, it has to be able to block
for a driver tag. We just had a bug where flush insertion
would block on tag allocation, while we had preempt disabled.
Ensure that we catch cases like that earlier next time.

Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 17:23:13 -06:00
Stephen Bates
0206319fdf blk-mq: Fix poll_stat for new size-based bucketing.
Fixes an issue where the size of the poll_stat array in request_queue
does not match the size expected by the new size based bucketing for
IO completion polling.

Fixes: 720b8ccc45 ("blk-mq: Add a polling specific stats function")
Signed-off-by: Stephen Bates <sbates@raithlin.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 17:10:48 -06:00
Jens Axboe
b00c53e8f4 blk-mq: fix schedule-while-atomic with scheduler attached
We must have dropped the ctx before we call
blk_mq_sched_insert_request() with can_block=true, otherwise we risk
that a flush request can block on insertion if we are currently out of
tags.

[   47.667190] BUG: scheduling while atomic: jbd2/sda2-8/2089/0x00000002
[   47.674493] Modules linked in: x86_pkg_temp_thermal btrfs xor zlib_deflate raid6_pq sr_mod cdre
[   47.690572] Preemption disabled at:
[   47.690584] [<ffffffff81326c7c>] blk_mq_sched_get_request+0x6c/0x280
[   47.701764] CPU: 1 PID: 2089 Comm: jbd2/sda2-8 Not tainted 4.11.0-rc7+ #271
[   47.709630] Hardware name: Dell Inc. PowerEdge T630/0NT78X, BIOS 2.3.4 11/09/2016
[   47.718081] Call Trace:
[   47.720903]  dump_stack+0x4f/0x73
[   47.724694]  ? blk_mq_sched_get_request+0x6c/0x280
[   47.730137]  __schedule_bug+0x6c/0xc0
[   47.734314]  __schedule+0x559/0x780
[   47.738302]  schedule+0x3b/0x90
[   47.741899]  io_schedule+0x11/0x40
[   47.745788]  blk_mq_get_tag+0x167/0x2a0
[   47.750162]  ? remove_wait_queue+0x70/0x70
[   47.754901]  blk_mq_get_driver_tag+0x92/0xf0
[   47.759758]  blk_mq_sched_insert_request+0x134/0x170
[   47.765398]  ? blk_account_io_start+0xd0/0x270
[   47.770679]  blk_mq_make_request+0x1b2/0x850
[   47.775766]  generic_make_request+0xf7/0x2d0
[   47.780860]  submit_bio+0x5f/0x120
[   47.784979]  ? submit_bio+0x5f/0x120
[   47.789631]  submit_bh_wbc.isra.46+0x10d/0x130
[   47.794902]  submit_bh+0xb/0x10
[   47.798719]  journal_submit_commit_record+0x190/0x210
[   47.804686]  ? _raw_spin_unlock+0x13/0x30
[   47.809480]  jbd2_journal_commit_transaction+0x180a/0x1d00
[   47.815925]  kjournald2+0xb6/0x250
[   47.820022]  ? kjournald2+0xb6/0x250
[   47.824328]  ? remove_wait_queue+0x70/0x70
[   47.829223]  kthread+0x10e/0x140
[   47.833147]  ? commit_timeout+0x10/0x10
[   47.837742]  ? kthread_create_on_node+0x40/0x40
[   47.843122]  ret_from_fork+0x29/0x40

Fixes: a4d907b6a3 ("blk-mq: streamline blk_mq_make_request")
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 16:42:02 -06:00
Stephen Bates
720b8ccc45 blk-mq: Add a polling specific stats function
Rather than bucketing IO statisics based on direction only we also
bucket based on the IO size. This leads to improved polling
performance. Update the bucket callback function and use it in the
polling latency estimation.

Signed-off-by: Stephen Bates <sbates@raithlin.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 15:29:40 -06:00
Stephen Bates
a37244e4cc blk-stat: convert blk-stat bucket callback to signed
In order to allow for filtering of IO based on some other properties
of the request than direction we allow the bucket function to return
an int.

If the bucket callback returns a negative do no count it in the stats
accumulation.

Signed-off-by: Stephen Bates <sbates@raithlin.com>

Fixed up Kyber scheduler stat callback.

Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 15:29:16 -06:00
Jens Axboe
3a07bb1d76 blk-mq: fix potential oops with polling and blk-mq scheduler
If we have a scheduler attached, blk_mq_tag_to_rq() on the
scheduled tags will return NULL if a request is no longer
in flight. This is different than using the normal tags,
where it will always return the fixed request. Check for
this condition for polling, in case we happen to enter
polling for a completed request.

The request address remains valid, so this check and return
should be perfectly safe.

Fixes: bd166ef183 ("blk-mq-sched: add framework for MQ capable IO schedulers")
Tested-by: Stephen Bates <sbates@raithlin.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 14:53:28 -06:00
Dan Williams
b0686260fe dax: introduce dax_direct_access()
Replace bdev_direct_access() with dax_direct_access() that uses
dax_device and dax_operations instead of a block_device and
block_device_operations for dax. Once all consumers of the old api have
been converted bdev_direct_access() will be deleted.

Given that block device partitioning decisions can cause dax page
alignment constraints to be violated this also introduces the
bdev_dax_pgoff() helper. It handles calculating a logical pgoff relative
to the dax_device and also checks for page alignment.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-04-20 11:57:52 -07:00
Christoph Hellwig
caf7df1227 block: remove the errors field from struct request
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:16:10 -06:00
Christoph Hellwig
453f83418d blk-mq: simplify __blk_mq_complete_request
Merge blk_mq_ipi_complete_request and blk_mq_stat_add into their only
caller.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:16:10 -06:00
Christoph Hellwig
08e0029aa2 blk-mq: remove the error argument to blk_mq_complete_request
Now that all drivers that call blk_mq_complete_requests have a
->complete callback we can remove the direct call to blk_mq_end_request,
as well as the error argument to blk_mq_complete_request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20 12:16:10 -06:00