Commit Graph

753202 Commits

Author SHA1 Message Date
Wei Yongjun
81cf54e01a nvmet: fix a typo in nvmet_file_ns_enable()
Fix a typo in nvmet_file_ns_enable().

Fixes: d5eff33ee6 ("nvmet: add simple file backed ns support")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.e>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-31 18:46:46 +02:00
Christoph Hellwig
cc456b65b7 nvme-fabrics: allow internal passthrough command on deleting controllers
Without this we can't cleanly shut down.

Based on analysis an an earlier patch from Hannes Reinecke.

Fixes: bb06ec3145 ("nvme: expand nvmf_check_if_ready checks")
Reported-by: Hannes Reinecke <hare@suse.de>
Tested-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: James Smart <james.smart@broadcom.com>
2018-05-31 18:46:46 +02:00
Christoph Hellwig
fe4a97918d nvme-loop: add support for multiple ports
This is useful at least for multipath testing.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
2018-05-30 08:05:18 +02:00
Christoph Hellwig
90ea5ca45c nvme-pci: simplify __nvme_submit_cmd
With recent CQ handling improvements we can now move the locking into
__nvme_submit_cmd.  Also remove the local tail variable to make the code
more obvious, remove the __ prefix in the name, and fix the comments
describing the function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
2018-05-30 08:04:26 +02:00
Keith Busch
b9cac43c2c nvme-pci: Rate limit the nvme timeout warnings
The block layer's timeout handling currently prevents drivers from
completing commands outside the timeout callback once blk-mq decides
they've expired. If a device breaks, this could potentially create many
thousands of timed out commands. There's nothing of value to be gleaned
from observing each of those messages, so this patch adds a rate limit
on them.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-30 08:04:25 +02:00
James Smart
ab4f47a9f4 nvme: allow duplicate controller if prior controller being deleted
The current checks for whether a new controller request "matches" an
existing controller ignores controller state and checks identity strings.
There are cases where an existing controller may be in its last steps of
deletion when they are "matched" by a new connection.

Change the behavior so that the new connection ignores controllers that
are deleted.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-30 08:03:23 +02:00
Christoph Hellwig
5de815a7ee block: remove parent device reference from struct bsg_class_device
Bsg holding a reference to the parent device may result in a crash if a
bsg file handle is closed after the parent device driver has unloaded.

Holding a reference is not really needed: the parent device must exist
between bsg_register_queue and bsg_unregister_queue.  Before the device
goes away the caller does blk_cleanup_queue so that all in-flight
requests to the device are gone and all new requests cannot pass beyond
the queue.  The queue itself is a refcounted object and it will stay
alive with a bsg file.

Based on analysis, previous patch and changelog from Anatoliy Glagolev.

Reported-by: Anatoliy Glagolev <glagolig@gmail.com>
Reviewed-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 13:00:25 -06:00
Jens Axboe
b7405176b5 Merge branch 'nvme-4.18-2' of git://git.infradead.org/nvme into for-4.18/block
Pull NVMe changes from Christoph:

"Here is the current batch of nvme updates for 4.18, we have a few more
 patches in the queue, but I'd like to get this pile into your tree
 and linux-next ASAP.

 The biggest item is support for file-backed namespaces in the NVMe
 target from Chaitanya, in addition to that we mostly small fixes from
 all the usual suspects."

* 'nvme-4.18-2' of git://git.infradead.org/nvme:
  nvme: fixup memory leak in nvme_init_identify()
  nvme: fix KASAN warning when parsing host nqn
  nvmet-loop: use nr_phys_segments when map rq to sgl
  nvmet-fc: increase LS buffer count per fc port
  nvmet: add simple file backed ns support
  nvmet: remove duplicate NULL initialization for req->ns
  nvmet: make a few error messages more generic
  nvme-fabrics: allow duplicate connections to the discovery controller
  nvme-fabrics: centralize discovery controller defaults
  nvme-fabrics: remove unnecessary controller subnqn validation
  nvme-fc: remove setting DNR on exception conditions
  nvme-rdma: stop admin queue before freeing it
  nvme-pci: Fix AER reset handling
  nvme-pci: set nvmeq->cq_vector after alloc cq/sq
  nvme: host: core: fix precedence of ternary operator
  nvme: fix lockdep warning in nvme_mpath_clear_current_path
2018-05-29 12:56:20 -06:00
Christoph Hellwig
5afb78356c block: don't print a message when the device went away
The information about a size change in this case just creates confusion.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
4163a03984 block: unexport check_disk_size_change
Only used in block_dev.c and the partitions code, and it should remain
that way..

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Jens Axboe
0b7576d8eb block: move ->timeout request member
After the recent timeout handling changes, we have two holes in
the struct. Move the timeout near the deadline, killing both,
and moving related members closer together. On my config on
x86-64, this shrinks struct request from 312 to 304 bytes.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
d1210d5afb blk-mq: simplify blk_mq_rq_timed_out
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
88b0cfad28 block: document the blk_eh_timer_return values
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
f6e7d48a78 block: remove BLK_EH_HANDLED
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
adb2b769d4 libiscsi: don't try to bypass SCSI EH
libiscsi is the only SCSI code that return BLK_EH_HANDLED, thus trying to
bypass the normal SCSI EH code.  We are going to remove this return value
at the block layer, and at least from a quick look it doesn't look too
harmful to try to send an abort for these cases, especially as the first
one should not actually be possible.  If this doesn't work out iscsi
will probably need its own eh_strategy_handler instead to just do the
right thing.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
ad73d6fead mmc: complete requests from ->timeout
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.

[While this keeps existing behavior it seems to mismatch the comment,
 maintainers please chime in!]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
1fc2b62edb scsi_transport_fc: complete requests from ->timeout
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
0df0bb080a null_blk: complete requests from ->timeout
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
c5fb85b7ff mtip32xx: complete requests from ->timeout
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
e5eab01704 nbd: complete requests from ->timeout
By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
db8c48e4b2 nvme: return BLK_EH_DONE from ->timeout
NVMe always completes the request before returning from ->timeout, either
by polling for it, or by disabling the controller.  Return BLK_EH_DONE so
that the block layer doesn't even try to complete it again.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Christoph Hellwig
6600593cbd block: rename BLK_EH_NOT_HANDLED to BLK_EH_DONE
The BLK_EH_NOT_HANDLED implies nothing happen, but very often that
is not what is happening - instead the driver already completed the
command.  Fix the symbolic name to reflect that a little better.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Keith Busch
12f5b93145 blk-mq: Remove generation seqeunce
This patch simplifies the timeout handling by relying on the request
reference counting to ensure the iterator is operating on an inflight
and truly timed out request. Since the reference counting prevents the
tag from being reallocated, the block layer no longer needs to prevent
drivers from completing their requests while the timeout handler is
operating on it: a driver completing a request is allowed to proceed to
the next state without additional syncronization with the block layer.

This also removes any need for generation sequence numbers since the
request lifetime is prevented from being reallocated as a new sequence
while timeout handling is operating on it.

To enables this a refcount is added to struct request so that request
users can be sure they're operating on the same request without it
changing while they're processing it.  The request's tag won't be
released for reuse until both the timeout handler and the completion
are done with it.

Signed-off-by: Keith Busch <keith.busch@intel.com>
[hch: slight cleanups, added back submission side hctx lock, use cmpxchg
 for completions]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:59:21 -06:00
Keith Busch
ad103e7983 blk-mq: Fix timeout and state order
The block layer had been setting the state to in-flight prior to updating
the timer. This is the wrong order since the timeout handler could observe
the in-flight state with the older timeout, believing the request had
expired when in fact it is just getting started.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:47:40 -06:00
Christoph Hellwig
01fc27d969 libata: remove ata_scsi_timed_out
As far as I can tell this function can't even be called any more, given
that ATA implements its own eh_strategy_handler with ata_scsi_error, which
never calls ->eh_timed_out.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-29 08:47:40 -06:00
Andy Shevchenko
ce4c3e19e5 bcache: Replace bch_read_string_list() by __sysfs_match_string()
Kernel library has a common function to match user input from sysfs
against an array of strings. Thus, replace bch_read_string_list() by
__sysfs_match_string().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-28 14:53:22 -06:00
Andy Shevchenko
ecb37ce9ba bcache: Move couple of functions to sysfs.c
There is couple of functions that are used exclusively in sysfs.c.
Move it to there and make them static.

Besides above, it will allow further clean up.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-28 14:53:20 -06:00
Andy Shevchenko
04cbc21137 bcache: Move couple of string arrays to sysfs.c
There is couple of string arrays that are used exclusively in sysfs.c.
Move it to there and make them static.

Besides above, it will allow further clean up.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-28 14:53:18 -06:00
Coly Li
0f0709e6bf bcache: stop bcache device when backing device is offline
Currently bcache does not handle backing device failure, if backing
device is offline and disconnected from system, its bcache device can still
be accessible. If the bcache device is in writeback mode, I/O requests even
can success if the requests hit on cache device. That is to say, when and
how bcache handles offline backing device is undefined.

This patch tries to handle backing device offline in a rather simple way,
- Add cached_dev->status_update_thread kernel thread to update backing
  device status in every 1 second.
- Add cached_dev->offline_seconds to record how many seconds the backing
  device is observed to be offline. If the backing device is offline for
  BACKING_DEV_OFFLINE_TIMEOUT (30) seconds, set dc->io_disable to 1 and
  call bcache_device_stop() to stop the bache device which linked to the
  offline backing device.

Now if a backing device is offline for BACKING_DEV_OFFLINE_TIMEOUT seconds,
its bcache device will be removed, then user space application writing on
it will get error immediately, and handler the device failure in time.

This patch is quite simple, does not handle more complicated situations.
Once the bcache device is stopped, users need to recovery the backing
device, register and attach it manually.

Changelog:
v3: call wait_for_kthread_stop() before exits kernel thread.
v2: remove "bcache: " prefix when calling pr_warn().
v1: initial version.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Michael Lyle <mlyle@lyle.org>
Cc: Junhui Tang <tang.junhui@zte.com.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-28 14:53:16 -06:00
Liu Bo
6723d8dc9d null_blk: add blocking description and remove lightnvm
- The description of 'blocking' is missing in null_blk.txt

- The 'lightnvm' parameter has been removed in null_blk.c

This updates both in null_blk.txt.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-25 08:51:58 -06:00
Hannes Reinecke
75c8b19a23 nvme: fixup memory leak in nvme_init_identify()
If nvme_get_effects_log() failed the 'id' buffer from the previous
nvme_identify_ctrl() call will never be freed.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Hannes Reinecke
1e5f446162 nvme: fix KASAN warning when parsing host nqn
The host nqn actually is smaller than the space reserved for it,
so we should be using strlcpy to keep KASAN happy.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Chaitanya Kulkarni
eb464833a2 nvmet-loop: use nr_phys_segments when map rq to sgl
Use blk_rq_nr_phys_segments() instead of blk_rq_payload_bytes() to check
if a command contains data to me mapped.  This fixes the case where
a struct requests contains LBAs, but no data will actually be send,
e.g. the pending Write Zeroes support.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
James Smart
17d78252ee nvmet-fc: increase LS buffer count per fc port
Todays limit on concurrent LS's is very small - 4 buffers. With large
subsystem counts or large numbers of initiators connecting, the limit
may be exceeded.

Raise the LS buffer count to 256.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Chaitanya Kulkarni
d5eff33ee6 nvmet: add simple file backed ns support
This patch adds simple file backed namespace support for NVMeOF target.

The new file io-cmd-file.c is responsible for handling the code for I/O
commands when ns is file backed. Also, we introduce mempools based slow
path using sync I/Os for file backed ns to ensure forward progress under
reclaim.

The old block device based implementation is moved to io-cmd-bdev.c and
use a "nvmet_bdev_" symbol prefix.  The enable/disable calls are also
move into the respective files.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: updated changelog, fixed double req->ns lookup in bdev case]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Chaitanya Kulkarni
618cff4285 nvmet: remove duplicate NULL initialization for req->ns
Remove the duplicate NULL initialization for req->ns.  req->ns is always
initialized to NULL in nvmet_req_init(), so there is no need to reset
it later on failures unless we have previously assigned a value to it.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Chaitanya Kulkarni
b40b83e365 nvmet: make a few error messages more generic
"nvmet_check_ctrl_status()" is called from admin-cmd.c along
with io-cmd.c, make the error message more generic.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Hannes Reinecke
181303d035 nvme-fabrics: allow duplicate connections to the discovery controller
The whole point of the discovery controller is that it can accept
multiple connections. Additionally the cmic field is not even defined for
the discovery controller identify page.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Hannes Reinecke
461fbc8f0e nvme-fabrics: centralize discovery controller defaults
When connecting to the discovery controller we have certain defaults
to observe, so centralize them to avoid inconsistencies due to argument
ordering.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
James Smart
ffecb0b452 nvme-fabrics: remove unnecessary controller subnqn validation
After creating the nvme controller, nvmf_create_ctrl() validates
the newly created subsysnqn vs the one specified by the options.

In general, this is an unnecessary check as the Connect message
should implicitly ensure this value matches.

With the change to the FC transport to do an asynchronous connect
for the first association create, the transport will return to
nvmf_create_ctrl() before that first association has been established,
thus the subnqn will not yet be set.

Remove the unnecessary validation.

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:15 +02:00
James Smart
90fcaf5d54 nvme-fc: remove setting DNR on exception conditions
Current code will set DNR if the controller is deleting or there is
an error during controller init. None of this is necessary.

Remove the code that sets DNR

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Jianchao Wang
2e050f00a0 nvme-rdma: stop admin queue before freeing it
For any failure after nvme_rdma_start_queue in
nvme_rdma_configure_admin_queue, the admin queue will be freed with the
NVME_RDMA_Q_LIVE flag still set.  Once nvme_rdma_stop_queue is invoked,
that will cause a use-after-free.
BUG: KASAN: use-after-free in rdma_disconnect+0x1f/0xe0 [rdma_cm]

To fix it, call nvme_rdma_stop_queue for all the failed cases after
nvme_rdma_start_queue.

Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Keith Busch
72cd4cc28e nvme-pci: Fix AER reset handling
The nvme timeout handling doesn't do anything if the pci channel is
offline, which is the case when recovering from PCI error event, so it
was a bad idea to sync the controller reset in this state. This patch
flushes the reset work in the error_resume callback instead when the
channel is back to online. This keeps AER handling serialized and
can recover from timeouts.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=199757
Fixes: cc1d5e749a ("nvme/pci: Sync controller reset for AER slot_reset")
Reported-by: Alex Gagniuc <mr.nuke.me@gmail.com>
Tested-by: Alex Gagniuc <mr.nuke.me@gmail.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Jianchao Wang
a8e3e0bb74 nvme-pci: set nvmeq->cq_vector after alloc cq/sq
Set cq_vector after alloc cq/sq, otherwise nvme_suspend_queue will invoke
free_irq for it and cause a 'Trying to free already-free IRQ  xxx'
warning if the create CQ/SQ command times out.

Signed-off-by: Jianchao Wang <jianchao.w.wang@oracle.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
[hch: fixed to pass a s16 and clean up the comment]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-05-25 16:50:12 +02:00
Joe Perches
5657a819a8 block drivers/block: Use octal not symbolic permissions
Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.

see: https://lkml.org/lkml/2016/8/2/1945

Done with automated conversion via:
$ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...>

Miscellanea:

o Wrapped modified multi-line calls to a single line where appropriate
o Realign modified multi-line calls to open parenthesis

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-24 13:38:59 -06:00
Ming Lei
e6fc464987 blk-mq: avoid starving tag allocation after allocating process migrates
When the allocation process is scheduled back and the mapped hw queue is
changed, fake one extra wake up on previous queue for compensating wake
up miss, so other allocations on the previous queue won't be starved.

This patch fixes one request allocation hang issue, which can be
triggered easily in case of very low nr_request.

The race is as follows:

1) 2 hw queues, nr_requests are 2, and wake_batch is one

2) there are 3 waiters on hw queue 0

3) two in-flight requests in hw queue 0 are completed, and only two
   waiters of 3 are waken up because of wake_batch, but both the two
   waiters can be scheduled to another CPU and cause to switch to hw
   queue 1

4) then the 3rd waiter will wait for ever, since no in-flight request
   is in hw queue 0 any more.

5) this patch fixes it by the fake wakeup when waiter is scheduled to
   another hw queue

Cc: <stable@vger.kernel.org>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>

Modified commit message to make it clearer, and make it apply on
top of the 4.18 branch.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-24 11:00:39 -06:00
Tejun Heo
f183464684 bdi: Move cgroup bdi_writeback to a dedicated low concurrency workqueue
From 0aa2e9b921d6db71150633ff290199554f0842a8 Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Wed, 23 May 2018 10:29:00 -0700

cgwb_release() punts the actual release to cgwb_release_workfn() on
system_wq.  Depending on the number of cgroups or block devices, there
can be a lot of cgwb_release_workfn() in flight at the same time.

We're periodically seeing close to 256 kworkers getting stuck with the
following stack trace and overtime the entire system gets stuck.

  [<ffffffff810ee40c>] _synchronize_rcu_expedited.constprop.72+0x2fc/0x330
  [<ffffffff810ee634>] synchronize_rcu_expedited+0x24/0x30
  [<ffffffff811ccf23>] bdi_unregister+0x53/0x290
  [<ffffffff811cd1e9>] release_bdi+0x89/0xc0
  [<ffffffff811cd645>] wb_exit+0x85/0xa0
  [<ffffffff811cdc84>] cgwb_release_workfn+0x54/0xb0
  [<ffffffff810a68d0>] process_one_work+0x150/0x410
  [<ffffffff810a71fd>] worker_thread+0x6d/0x520
  [<ffffffff810ad3dc>] kthread+0x12c/0x160
  [<ffffffff81969019>] ret_from_fork+0x29/0x40
  [<ffffffffffffffff>] 0xffffffffffffffff

The events leading to the lockup are...

1. A lot of cgwb_release_workfn() is queued at the same time and all
   system_wq kworkers are assigned to execute them.

2. They all end up calling synchronize_rcu_expedited().  One of them
   wins and tries to perform the expedited synchronization.

3. However, that invovles queueing rcu_exp_work to system_wq and
   waiting for it.  Because #1 is holding all available kworkers on
   system_wq, rcu_exp_work can't be executed.  cgwb_release_workfn()
   is waiting for synchronize_rcu_expedited() which in turn is waiting
   for cgwb_release_workfn() to free up some of the kworkers.

We shouldn't be scheduling hundreds of cgwb_release_workfn() at the
same time.  There's nothing to be gained from that.  This patch
updates cgwb release path to use a dedicated percpu workqueue with
@max_active of 1.

While this resolves the problem at hand, it might be a good idea to
isolate rcu_exp_work to its own workqueue too as it can be used from
various paths and is prone to this sort of indirect A-A deadlocks.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-23 15:28:50 -06:00
Josef Bacik
6df133a149 nbd: set discard granularity properly
For some reason we had discard granularity set to 512 always even when
discards were disabled.  Fix this by having the default be 0, and then
if we turn it on set the discard granularity to the blocksize.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-23 15:27:26 -06:00
Ivan Bornyakov
e9a9853c23 nvme: host: core: fix precedence of ternary operator
Ternary operator have lower precedence then bitwise or, so 'cdw10' was
calculated wrong.

Signed-off-by: Ivan Bornyakov <brnkv.i1@gmail.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
2018-05-23 09:11:37 -06:00
Johannes Thumshirn
978628ec79 nvme: fix lockdep warning in nvme_mpath_clear_current_path
When running blktest's nvme/005 with a lockdep enabled kernel the test
case fails due to the following lockdep splat in dmesg:

 =============================
 WARNING: suspicious RCU usage
 4.17.0-rc5 #881 Not tainted
 -----------------------------
 drivers/nvme/host/nvme.h:457 suspicious rcu_dereference_check() usage!

 other info that might help us debug this:

 rcu_scheduler_active = 2, debug_locks = 1
 3 locks held by kworker/u32:5/1102:
  #0:         (ptrval) ((wq_completion)"nvme-wq"){+.+.}, at: process_one_work+0x152/0x5c0
  #1:         (ptrval) ((work_completion)(&ctrl->scan_work)){+.+.}, at: process_one_work+0x152/0x5c0
  #2:         (ptrval) (&subsys->lock#2){+.+.}, at: nvme_ns_remove+0x43/0x1c0 [nvme_core]

The only caller of nvme_mpath_clear_current_path() is nvme_ns_remove()
which holds the subsys lock so it's likely a false positive, but when
using rcu_access_pointer(), we're telling rcu and lockdep that we're
only after the pointer falue.

Fixes: 32acab3181 ("nvme: implement multipath access to nvme subsystems")
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Suggested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
2018-05-23 08:58:27 -06:00