Commit Graph

5335 Commits

Author SHA1 Message Date
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
Christoph Hellwig
ff005a0662 block: sanitize blk_get_request calling conventions
Switch everyone to blk_get_request_flags, and then rename
blk_get_request_flags to blk_get_request.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-14 08:55:12 -06:00
Omar Sandoval
522a777566 block: consolidate struct request timestamp fields
Currently, struct request has four timestamp fields:

- A start time, set at get_request time, in jiffies, used for iostats
- An I/O start time, set at start_request time, in ktime nanoseconds,
  used for blk-stats (i.e., wbt, kyber, hybrid polling)
- Another start time and another I/O start time, used for cfq and bfq

These can all be consolidated into one start time and one I/O start
time, both in ktime nanoseconds, shaving off up to 16 bytes from struct
request depending on the kernel config.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-09 08:33:09 -06:00
Coly Li
09a44ca211 bcache: use pr_info() to inform duplicated CACHE_SET_IO_DISABLE set
It is possible that multiple I/O requests hits on failed cache device or
backing device, therefore it is quite common that CACHE_SET_IO_DISABLE is
set already when a task tries to set the bit from bch_cache_set_error().
Currently the message "CACHE_SET_IO_DISABLE already set" is printed by
pr_warn(), which might mislead users to think a serious fault happens in
source code.

This patch uses pr_info() to print the information in such situation,
avoid extra worries. This information is helpful to understand bcache
behavior in cache device failures, so I still keep them in source code.

Fixes: 771f393e8f ("bcache: add CACHE_SET_IO_DISABLE to struct cache_set flags")
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-03 08:35:16 -06:00
Coly Li
4fd8e13843 bcache: set dc->io_disable to true in conditional_stop_bcache_device()
Commit 7e027ca4b5 ("bcache: add stop_when_cache_set_failed option to
backing device") adds stop_when_cache_set_failed option and stops bcache
device if stop_when_cache_set_failed is auto and there is dirty data on
broken cache device. There might exists a small time gap that the cache
set is released and set to NULL but bcache device is not released yet
(because they are released in parallel). During this time gap, dc->c is
NULL so CACHE_SET_IO_DISABLE won't be checked, and dc->io_disable is still
false, so new coming I/O requests will be accepted and directly go into
backing device as no cache set attached to. If there is dirty data on
cache device, this behavior may introduce potential inconsistent data.

This patch sets dc->io_disable to true before calling bcache_device_stop()
to make sure the backing device will reject new coming I/O request as
well, so even in the small time gap no I/O will directly go into backing
device to corrupt data consistency.

Fixes: 7e027ca4b5 ("bcache: add stop_when_cache_set_failed option to backing device")
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-03 08:35:15 -06:00
Coly Li
ecb2ba8cb8 bcache: add wait_for_kthread_stop() in bch_allocator_thread()
When CACHE_SET_IO_DISABLE is set on cache set flags, bcache allocator
thread routine bch_allocator_thread() may stop the while-loops and
exit. Then it is possible to observe the following kernel oops message,

[  631.068366] bcache: bch_btree_insert() error -5
[  631.069115] bcache: cached_dev_detach_finish() Caching disabled for sdf
[  631.070220] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[  631.070250] PGD 0 P4D 0
[  631.070261] Oops: 0002 [#1] SMP PTI
[snipped]
[  631.070578] Workqueue: events cache_set_flush [bcache]
[  631.070597] RIP: 0010:exit_creds+0x1b/0x50
[  631.070610] RSP: 0018:ffffc9000705fe08 EFLAGS: 00010246
[  631.070626] RAX: 0000000000000001 RBX: ffff880a622ad300 RCX: 000000000000000b
[  631.070645] RDX: 0000000000000601 RSI: 000000000000000c RDI: 0000000000000000
[  631.070663] RBP: ffff880a622ad300 R08: ffffea00190c66e0 R09: 0000000000000200
[  631.070682] R10: ffff880a48123000 R11: ffff880000000000 R12: 0000000000000000
[  631.070700] R13: ffff880a4b160e40 R14: ffff880a4b160000 R15: 0ffff880667e2530
[  631.070719] FS:  0000000000000000(0000) GS:ffff880667e00000(0000) knlGS:0000000000000000
[  631.070740] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  631.070755] CR2: 0000000000000000 CR3: 000000000200a001 CR4: 00000000003606e0
[  631.070774] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  631.070793] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  631.070811] Call Trace:
[  631.070828]  __put_task_struct+0x55/0x160
[  631.070845]  kthread_stop+0xee/0x100
[  631.070863]  cache_set_flush+0x11d/0x1a0 [bcache]
[  631.070879]  process_one_work+0x146/0x340
[  631.070892]  worker_thread+0x47/0x3e0
[  631.070906]  kthread+0xf5/0x130
[  631.070917]  ? max_active_store+0x60/0x60
[  631.070930]  ? kthread_bind+0x10/0x10
[  631.070945]  ret_from_fork+0x35/0x40
[snipped]
[  631.071017] RIP: exit_creds+0x1b/0x50 RSP: ffffc9000705fe08
[  631.071033] CR2: 0000000000000000
[  631.071045] ---[ end trace 011c63a24b22c927 ]---
[  631.071085] bcache: bcache_device_free() bcache0 stopped

The reason is when cache_set_flush() tries to call kthread_stop() to stop
allocator thread, but it exits already due to cache device I/O errors.

This patch adds wait_for_kthread_stop() at tail of bch_allocator_thread(),
to prevent the thread routine exiting directly. Then the allocator thread
can be blocked at wait_for_kthread_stop() and wait for cache_set_flush()
to stop it by calling kthread_stop().

changelog:
v3: add Reviewed-by from Hannnes.
v2: not directly return from allocator_wait(), move 'return 0' to tail of
    bch_allocator_thread().
v1: initial version.

Fixes: 771f393e8f ("bcache: add CACHE_SET_IO_DISABLE to struct cache_set flags")
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-03 08:35:13 -06:00
Coly Li
bf78980fcc bcache: count backing device I/O error for writeback I/O
Commit c7b7bd0740 ("bcache: add io_disable to struct cached_dev")
counts backing device I/O requets and set dc->io_disable to true if error
counters exceeds dc->io_error_limit. But it only counts I/O errors for
regular I/O request, neglects errors of write back I/Os when backing device
is offline.

This patch counts the errors of writeback I/Os, in dirty_endio() if
bio->bi_status is  not 0, it means error happens when writing dirty keys
to backing device, then bch_count_backing_io_errors() is called.

By this fix, even there is no reqular I/O request coming, if writeback I/O
errors exceed dc->io_error_limit, the bcache device may still be stopped
for the broken backing device.

Fixes: c7b7bd0740 ("bcache: add io_disable to struct cached_dev")
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-03 08:35:12 -06:00
Coly Li
6147305c73 bcache: set CACHE_SET_IO_DISABLE in bch_cached_dev_error()
Commit c7b7bd0740 ("bcache: add io_disable to struct cached_dev") tries
to stop bcache device by calling bcache_device_stop() when too many I/O
errors happened on backing device. But if there is internal I/O happening
on cache device (writeback scan, garbage collection, etc), a regular I/O
request triggers the internal I/Os may still holds a refcount of dc->count,
and the refcount may only be dropped after the internal I/O stopped.

By this patch, bch_cached_dev_error() will check if the backing device is
attached to a cache set, if yes that CACHE_SET_IO_DISABLE will be set to
flags of this cache set. Then internal I/Os on cache device will be
rejected and stopped immediately, and the bcache device can be stopped.

For people who are not familiar with the interesting refcount dependance,
let me explain a bit more how the fix works. Example the writeback thread
will scan cache device for dirty data writeback purpose. Before it stopps,
it holds a refcount of dc->count. When CACHE_SET_IO_DISABLE bit is set,
the internal I/O will stopped and the while-loop in bch_writeback_thread()
quits and calls cached_dev_put() to drop dc->count. If this is the last
refcount to drop, then cached_dev_detach_finish() will be called. In this
call back function, in turn closure_put(dc->disk.cl) is called to drop a
refcount of closure dc->disk.cl. If this is the last refcount of this
closure to drop, then cached_dev_flush() will be called. Then the cached
device is freed. So if CACHE_SET_IO_DISABLE is not set, the bache device
can not be stopped until all inernal cache device I/O stopped. For large
size cache device, and writeback thread competes locks with gc thread,
there might be a quite long time to wait.

Fixes: c7b7bd0740 ("bcache: add io_disable to struct cached_dev")
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-03 08:35:10 -06:00
Coly Li
6e916a7eb1 bcache: store disk name in struct cache and struct cached_dev
Current code uses bdevname() or bio_devname() to reference gendisk
disk name when bcache needs to display the disk names in kernel message.
It was safe before bcache device failure handling patch set merged in,
because when devices are failed, there was deadlock to prevent bcache
printing error messages with gendisk disk name. But after the failure
handling patch set merged, the deadlock is fixed, so it is possible
that the gendisk structure bdev->hd_disk is released when bdevname() is
called to reference bdev->bd_disk->disk_name[]. This is why I receive
bug report of NULL pointers deference panic.

This patch stores gendisk disk name in a buffer inside struct cache and
struct cached_dev, then print out the offline device name won't reference
bdev->hd_disk anymore. And this patch also avoids extra function calls
of bdevname() and bio_devnmae().

Changelog:
v3, add Reviewed-by from Hannes.
v2, call bdevname() earlier in register_bdev()
v1, first version with segguestion from Junhui Tang.

Fixes: c7b7bd0740 ("bcache: add io_disable to struct cached_dev")
Fixes: 5138ac6748 ("bcache: fix misleading error message in bch_count_io_errors()")
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-03 08:35:08 -06:00
Linus Torvalds
7768ee3f45 Merge tag 'md/4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md
Pull MD fixes from Shaohua Li:
 "Three small fixes for MD:

   - md-cluster fix for faulty device from Guoqing

   - writehint fix for writebehind IO for raid1 from Mariusz

   - a live lock fix for interrupted recovery from Yufen"

* tag 'md/4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  raid1: copy write hint from master bio to behind bio
  md/raid1: exit sync request if MD_RECOVERY_INTR is set
  md-cluster: don't update recovery_offset for faulty device
2018-04-20 10:39:44 -07:00
Linus Torvalds
9f3a0941fb libnvdimm for 4.17
* A rework of the filesytem-dax implementation provides for detection of
   unmap operations (truncate / hole punch) colliding with in-progress
   device-DMA. A fix for these collisions remains a work-in-progress
   pending resolution of truncate latency and starvation regressions.
 
 * The of_pmem driver expands the users of libnvdimm outside of x86 and
   ACPI to describe an implementation of persistent memory on PowerPC with
   Open Firmware / Device tree.
 
 * Address Range Scrub (ARS) handling is completely rewritten to account for
   the fact that ARS may run for 100s of seconds and there is no platform
   defined way to cancel it. ARS will now no longer block namespace
   initialization.
 
 * The NVDIMM Namespace Label implementation is updated to handle label
   areas as small as 1K, down from 128K.
 
 * Miscellaneous cleanups and updates to unit test infrastructure.
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Merge tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:
 "This cycle was was not something I ever want to repeat as there were
  several late changes that have only now just settled.

  Half of the branch up to commit d2c997c0f1 ("fs, dax: use
  page->mapping to warn...") have been in -next for several releases.
  The of_pmem driver and the address range scrub rework were late
  arrivals, and the dax work was scaled back at the last moment.

  The of_pmem driver missed a previous merge window due to an oversight.
  A sense of obligation to rectify that miss is why it is included for
  4.17. It has acks from PowerPC folks. Stephen reported a build failure
  that only occurs when merging it with your latest tree, for now I have
  fixed that up by disabling modular builds of of_pmem. A test merge
  with your tree has received a build success report from the 0day robot
  over 156 configs.

  An initial version of the ARS rework was submitted before the merge
  window. It is self contained to libnvdimm, a net code reduction, and
  passing all unit tests.

  The filesystem-dax changes are based on the wait_var_event()
  functionality from tip/sched/core. However, late review feedback
  showed that those changes regressed truncate performance to a large
  degree. The branch was rewound to drop the truncate behavior change
  and now only includes preparation patches and cleanups (with full acks
  and reviews). The finalization of this dax-dma-vs-trnucate work will
  need to wait for 4.18.

  Summary:

   - A rework of the filesytem-dax implementation provides for detection
     of unmap operations (truncate / hole punch) colliding with
     in-progress device-DMA. A fix for these collisions remains a
     work-in-progress pending resolution of truncate latency and
     starvation regressions.

   - The of_pmem driver expands the users of libnvdimm outside of x86
     and ACPI to describe an implementation of persistent memory on
     PowerPC with Open Firmware / Device tree.

   - Address Range Scrub (ARS) handling is completely rewritten to
     account for the fact that ARS may run for 100s of seconds and there
     is no platform defined way to cancel it. ARS will now no longer
     block namespace initialization.

   - The NVDIMM Namespace Label implementation is updated to handle
     label areas as small as 1K, down from 128K.

   - Miscellaneous cleanups and updates to unit test infrastructure"

* tag 'libnvdimm-for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (39 commits)
  libnvdimm, of_pmem: workaround OF_NUMA=n build error
  nfit, address-range-scrub: add module option to skip initial ars
  nfit, address-range-scrub: rework and simplify ARS state machine
  nfit, address-range-scrub: determine one platform max_ars value
  powerpc/powernv: Create platform devs for nvdimm buses
  doc/devicetree: Persistent memory region bindings
  libnvdimm: Add device-tree based driver
  libnvdimm: Add of_node to region and bus descriptors
  libnvdimm, region: quiet region probe
  libnvdimm, namespace: use a safe lookup for dimm device name
  libnvdimm, dimm: fix dpa reservation vs uninitialized label area
  libnvdimm, testing: update the default smart ctrl_temperature
  libnvdimm, testing: Add emulation for smart injection commands
  nfit, address-range-scrub: introduce nfit_spa->ars_state
  libnvdimm: add an api to cast a 'struct nd_region' to its 'struct device'
  nfit, address-range-scrub: fix scrub in-progress reporting
  dax, dm: allow device-mapper to operate without dax support
  dax: introduce CONFIG_DAX_DRIVER
  fs, dax: use page->mapping to warn if truncate collides with a busy page
  ext2, dax: introduce ext2_dax_aops
  ...
2018-04-10 10:25:57 -07:00
Dan Williams
e13e75b86e Merge branch 'for-4.17/dax' into libnvdimm-for-next 2018-04-09 10:50:17 -07:00
Mariusz Dabrowski
dba40d46eb raid1: copy write hint from master bio to behind bio
Signed-off-by: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Reviewed-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Reviewed-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-04-09 08:54:34 -07:00
Yufen Yu
8c24259323 md/raid1: exit sync request if MD_RECOVERY_INTR is set
We met a sync thread stuck as follows:

 raid1_sync_request+0x2c9/0xb50
 md_do_sync+0x983/0xfa0
 md_thread+0x11c/0x160
 kthread+0x111/0x130
 ret_from_fork+0x35/0x40
 0xffffffffffffffff

At the same time, there is a stuck mdadm thread (mdadm --manage
/dev/md2 --add /dev/sda). It is trying to stop the sync thread:

 kthread_stop+0x42/0xf0
 md_unregister_thread+0x3a/0x70
 md_reap_sync_thread+0x15/0x160
 action_store+0x142/0x2a0
 md_attr_store+0x6c/0xb0
 kernfs_fop_write+0x102/0x180
 __vfs_write+0x33/0x170
 vfs_write+0xad/0x1a0
 SyS_write+0x52/0xc0
 do_syscall_64+0x6e/0x190
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Debug tools show that the sync thread is waiting in raise_barrier(),
until raid1d() end all normal IO bios into bio_end_io_list(introduced
in commit 55ce74d4bf). But, raid1d() cannot end these bios if
MD_CHANGE_PENDING bit is set. It needs to get mddev->reconfig_mutex lock
and then clear the bit in md_check_recovery().
However, the lock is holding by mdadm in action_store().

Thus, there is a loop:
mdadm waiting for sync thread to stop, sync thread waiting for
raid1d() to end bios, raid1d() waiting for mdadm to release
mddev->reconfig_mutex lock and then it can end bios.

Fix this by checking MD_RECOVERY_INTR while waiting in raise_barrier(),
so that sync thread can exit while mdadm is stoping the sync thread.

Fixes: 55ce74d4bf ("md/raid1: ensure device failure recorded before write request returns.")
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-04-09 08:41:16 -07:00
Guoqing Jiang
0ea9924abe md-cluster: don't update recovery_offset for faulty device
Device could become faulty when clustered array handling
METADATA_UPDATED msg, so we don't need to call read_rdev
for this device.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-04-09 08:39:36 -07:00
Linus Torvalds
83c7c18b16 - DM core passthrough ioctl fix to retain reference to DM table, and
that table's block devices, while issuing the ioctl to one of those
   block devices.
 
 - DM core passthrough ioctl fix to _not_ override the fmode_t used to
   issue the ioctl.  Overriding by using the fmode_t that the block
   device was originally open with during DM table load is a liability.
 
 - Add DM core support for secure erase forwarding and update the DM
   linear and DM striped targets to support them.
 
 - A DM core 4.16 stable fix to allow abnormal IO (e.g. discard, write
   same, write zeroes) for targets that make use of the non-splitting IO
   variant (as is done for multipath or thinp when layered directly on
   NVMe).
 
 - Allow DM targets to return a payload in response to a DM message that
   they are sent.  This is useful for DM targets that would like to
   provide statistics data in response to DM messages.
 
 - Update DM bufio to support non-power-of-2 block sizes.  Numerous other
   related changes prepare the DM bufio code for this support.
 
 - Fix DM crypt to use a bounded amount of memory across the entire
   system.  This is to avoid OOM that can otherwise occur in response to
   certain pathological IO workloads (e.g. discarding a large DM crypt
   device).
 
 - Add a 'check_at_most_once' feature to the DM verity target to allow
   verity to be used on mobile devices that have very limited resources.
 
 - Fix the DM integrity target to fail early if a keyed algorithm
   (e.g. HMAC) is to be used but the key isn't set.
 
 - Add non-power-of-2 support to the DM unstripe target.
 
 - Eliminate the use of a Variable Length Array in the DM stripe target.
 
 - Update the DM log-writes target to record metadata (REQ_META flag).
 
 - DM raid fixes for its nosync status and some variable range issues.
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Merge tag 'for-4.17/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - DM core passthrough ioctl fix to retain reference to DM table, and
   that table's block devices, while issuing the ioctl to one of those
   block devices.

 - DM core passthrough ioctl fix to _not_ override the fmode_t used to
   issue the ioctl. Overriding by using the fmode_t that the block
   device was originally open with during DM table load is a liability.

 - Add DM core support for secure erase forwarding and update the DM
   linear and DM striped targets to support them.

 - A DM core 4.16 stable fix to allow abnormal IO (e.g. discard, write
   same, write zeroes) for targets that make use of the non-splitting IO
   variant (as is done for multipath or thinp when layered directly on
   NVMe).

 - Allow DM targets to return a payload in response to a DM message that
   they are sent. This is useful for DM targets that would like to
   provide statistics data in response to DM messages.

 - Update DM bufio to support non-power-of-2 block sizes. Numerous other
   related changes prepare the DM bufio code for this support.

 - Fix DM crypt to use a bounded amount of memory across the entire
   system. This is to avoid OOM that can otherwise occur in response to
   certain pathological IO workloads (e.g. discarding a large DM crypt
   device).

 - Add a 'check_at_most_once' feature to the DM verity target to allow
   verity to be used on mobile devices that have very limited resources.

 - Fix the DM integrity target to fail early if a keyed algorithm (e.g.
   HMAC) is to be used but the key isn't set.

 - Add non-power-of-2 support to the DM unstripe target.

 - Eliminate the use of a Variable Length Array in the DM stripe target.

 - Update the DM log-writes target to record metadata (REQ_META flag).

 - DM raid fixes for its nosync status and some variable range issues.

* tag 'for-4.17/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (28 commits)
  dm: remove fmode_t argument from .prepare_ioctl hook
  dm: hold DM table for duration of ioctl rather than use blkdev_get
  dm raid: fix parse_raid_params() variable range issue
  dm verity: make verity_for_io_block static
  dm verity: add 'check_at_most_once' option to only validate hashes once
  dm bufio: don't embed a bio in the dm_buffer structure
  dm bufio: support non-power-of-two block sizes
  dm bufio: use slab cache for dm_buffer structure allocations
  dm bufio: reorder fields in dm_buffer structure
  dm bufio: relax alignment constraint on slab cache
  dm bufio: remove code that merges slab caches
  dm bufio: get rid of slab cache name allocations
  dm bufio: move dm-bufio.h to include/linux/
  dm bufio: delete outdated comment
  dm: add support for secure erase forwarding
  dm: backfill abnormal IO support to non-splitting IO submission
  dm raid: fix nosync status
  dm mpath: use DM_MAPIO_SUBMITTED instead of magic number 0 in process_queued_bios()
  dm stripe: get rid of a Variable Length Array (VLA)
  dm log writes: record metadata flag for better flags record
  ...
2018-04-06 11:50:19 -07:00
Linus Torvalds
3526dd0c78 for-4.17/block-20180402
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Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:
 "It's a pretty quiet round this time, which is nice. This contains:

   - series from Bart, cleaning up the way we set/test/clear atomic
     queue flags.

   - series from Bart, fixing races between gendisk and queue
     registration and removal.

   - set of bcache fixes and improvements from various folks, by way of
     Michael Lyle.

   - set of lightnvm updates from Matias, most of it being the 1.2 to
     2.0 transition.

   - removal of unused DIO flags from Nikolay.

   - blk-mq/sbitmap memory ordering fixes from Omar.

   - divide-by-zero fix for BFQ from Paolo.

   - minor documentation patches from Randy.

   - timeout fix from Tejun.

   - Alpha "can't write a char atomically" fix from Mikulas.

   - set of NVMe fixes by way of Keith.

   - bsg and bsg-lib improvements from Christoph.

   - a few sed-opal fixes from Jonas.

   - cdrom check-disk-change deadlock fix from Maurizio.

   - various little fixes, comment fixes, etc from various folks"

* tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits)
  blk-mq: Directly schedule q->timeout_work when aborting a request
  blktrace: fix comment in blktrace_api.h
  lightnvm: remove function name in strings
  lightnvm: pblk: remove some unnecessary NULL checks
  lightnvm: pblk: don't recover unwritten lines
  lightnvm: pblk: implement 2.0 support
  lightnvm: pblk: implement get log report chunk
  lightnvm: pblk: rename ppaf* to addrf*
  lightnvm: pblk: check for supported version
  lightnvm: implement get log report chunk helpers
  lightnvm: make address conversions depend on generic device
  lightnvm: add support for 2.0 address format
  lightnvm: normalize geometry nomenclature
  lightnvm: complete geo structure with maxoc*
  lightnvm: add shorten OCSSD version in geo
  lightnvm: add minor version to generic geometry
  lightnvm: simplify geometry structure
  lightnvm: pblk: refactor init/exit sequences
  lightnvm: Avoid validation of default op value
  lightnvm: centralize permission check for lightnvm ioctl
  ...
2018-04-05 14:27:02 -07:00
Mike Snitzer
5bd5e8d891 dm: remove fmode_t argument from .prepare_ioctl hook
Use the fmode_t that is passed to dm_blk_ioctl() rather than
inconsistently (varies across targets) drop it on the floor by
overriding it with the fmode_t stored in 'struct dm_dev'.

All the persistent reservation functions weren't using the fmode_t they
got back from .prepare_ioctl so remove them.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-04 12:12:39 -04:00
Mike Snitzer
971888c469 dm: hold DM table for duration of ioctl rather than use blkdev_get
Commit 519049afea ("dm: use blkdev_get rather than bdgrab when issuing
pass-through ioctl") inadvertantly introduced a regression relative to
users of device cgroups that issue ioctls (e.g. libvirt).  Using
blkdev_get() in DM's passthrough ioctl support implicitly introduced a
cgroup permissions check that would fail unless care were taken to add
all devices in the IO stack to the device cgroup.  E.g. rather than just
adding the top-level DM multipath device to the cgroup all the
underlying devices would need to be allowed.

Fix this, to no longer require allowing all underlying devices, by
simply holding the live DM table (which includes the table's original
blkdev_get() reference on the blockdevice that the ioctl will be issued
to) for the duration of the ioctl.

Also, bump the DM ioctl version so a user can know that their device
cgroup allow workaround is no longer needed.

Reported-by: Michal Privoznik <mprivozn@redhat.com>
Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 519049afea ("dm: use blkdev_get rather than bdgrab when issuing pass-through ioctl")
Cc: stable@vger.kernel.org # 4.16
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-04 12:12:38 -04:00
Heinz Mauelshagen
13bc62d4a6 dm raid: fix parse_raid_params() variable range issue
parse_raid_params() compares variable "int value" with INT_MAX.

E.g. related Coverity report excerpt:
   CID 1364818 (#2 of 3): Operands don't affect result (CONSTANT_EXPRESSION_RESULT) [select issue]
1433                        if (value > INT_MAX) {

Fix by changing checks to avoid INT_MAX.

Whilst on it, avoid unnecessary checks against constants
and add check for sane recovery speed min/max.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-04 12:12:37 -04:00
weiyongjun (A)
d4b1aaf53c dm verity: make verity_for_io_block static
Fixes the following sparse warning:

drivers/md/dm-verity-target.c:375:6: warning:
 symbol 'verity_for_io_block' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-04 12:12:36 -04:00
Patrik Torstensson
843f38d382 dm verity: add 'check_at_most_once' option to only validate hashes once
This allows platforms that are CPU/memory contrained to verify data
blocks only the first time they are read from the data device, rather
than every time.  As such, it provides a reduced level of security
because only offline tampering of the data device's content will be
detected, not online tampering.

Hash blocks are still verified each time they are read from the hash
device, since verification of hash blocks is less performance critical
than data blocks, and a hash block will not be verified any more after
all the data blocks it covers have been verified anyway.

This option introduces a bitset that is used to check if a block has
been validated before or not.  A block can be validated more than once
as there is no thread protection for the bitset.

These changes were developed and tested on entry-level Android Go
devices.

Signed-off-by: Patrik Torstensson <totte@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:29 -04:00
Mikulas Patocka
45354f1eb6 dm bufio: don't embed a bio in the dm_buffer structure
The bio structure consumes a substantial part of dm_buffer.  The bio
structure is only needed when doing I/O on the buffer, thus we don't
have to embed it in the buffer.

Allocate the bio structure only when doing I/O.

We don't need to create a bio_set because, in case of allocation
failure, dm-bufio falls back to using dm-io (which keeps its own
bio_set).

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:29 -04:00
Mikulas Patocka
f51f2e0a7f dm bufio: support non-power-of-two block sizes
Support block sizes that are not a power-of-two (but they must be a
multiple of 512b).  As always, a slab cache is used for allocations.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:28 -04:00
Mikulas Patocka
359dbf19ab dm bufio: use slab cache for dm_buffer structure allocations
kmalloc padded to the next power of two, using a slab cache avoids this.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:27 -04:00
Mikulas Patocka
03b0293959 dm bufio: reorder fields in dm_buffer structure
Reorder fields in dm_buffer structure to improve packing and reduce
structure size.  The compiler allocates 32-bit integer for field 'enum
data_mode', so change it to unsigned char.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:26 -04:00
Mikulas Patocka
6b5e718cc1 dm bufio: relax alignment constraint on slab cache
The I/O buffer doesn't have to be aligned on block size granularity,
relax alignment to ARCH_KMALLOC_MINALIGN (required to allow DMA from
slab cache memory on some architectures).

Also, set SLAB_RECLAIM_ACCOUNT so that the memory allocated from the
cache is accounted as reclaimable and doesn't inflate the 'used' entry
in the free command.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:25 -04:00
Mikulas Patocka
21bb132767 dm bufio: remove code that merges slab caches
All slab allocators can merge duplicate caches.  So dm-bufio doesn't
need extra slab merging logic.  Instead it can just allocate one slab
cache per client and let the allocator merge them.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:25 -04:00
Mikulas Patocka
eeb67a0ba0 dm bufio: get rid of slab cache name allocations
dm-bufio keeps the dm_bufio_cache_names array that holds names of the
slab caches.

Since the commit db265eca77 ("mm/sl[aou]b: Move duping of slab name to
slab_common.c"), the kernel automatically duplicates the slab cache name
when creating the slab cache, so we no longer have to keep the name
allocated.

Remove the code that allocates the slab names and keeps them around.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:24 -04:00
Mikulas Patocka
afa53df869 dm bufio: move dm-bufio.h to include/linux/
Move dm-bufio.h to include/linux/ so that external GPL'd DM target
modules can use it.

It is better to allow the use of dm-bufio than force external modules
to implement the equivalent buffered IO mechanism in some new way.  The
hope is this will encourage the use of dm-bufio; which will then make it
easier for a GPL'd external DM target module to be included upstream.

A couple dm-bufio EXPORT_SYMBOL exports have also been updated to use
EXPORT_SYMBOL_GPL.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:23 -04:00
Mikulas Patocka
1f013174b3 dm bufio: delete outdated comment
This comment was true when dm-bufio was written but, since 4.3, bios can
now have arbitrary size and the driver splits them.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:22 -04:00
Denis Semakin
00716545c8 dm: add support for secure erase forwarding
Set QUEUE_FLAG_SECERASE in DM device's queue_flags if a DM table's
data devices support secure erase.

Also, add support for secure erase to both the linear and striped
targets.

Signed-off-by: Denis Semakin <d.semakin@omprussia.ru>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:21 -04:00
Mike Snitzer
0519c71e8d dm: backfill abnormal IO support to non-splitting IO submission
Otherwise, these abnormal IOs would be sent to the DM target
regardless of whether the target advertised support for them.

Factor out __process_abnormal_io() from __split_and_process_non_flush()
so that discards, write same, etc may be conditionally processed.

Fixes: 978e51ba3 ("dm: optimize bio-based NVMe IO submission")
Cc: stable@vger.kernel.org # 4.16
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:20 -04:00
Heinz Mauelshagen
880bcce0dc dm raid: fix nosync status
Fix a race for "nosync" activations providing "aa.." device health
characters and "0/N" sync ratio rather than "AA..." and "N/N".  Occurs
when status for the raid set is retrieved during resume before the MD
sync thread starts and clears the MD_RECOVERY_NEEDED flag.

Cc: stable@vger.kernel.org # 4.16+
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:19 -04:00
Wang Sheng-Hui
8192a0cd76 dm mpath: use DM_MAPIO_SUBMITTED instead of magic number 0 in process_queued_bios()
Signed-off-by: Wang Sheng-Hui <shhuiw@foxmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:19 -04:00
Tycho Andersen
706dd22f12 dm stripe: get rid of a Variable Length Array (VLA)
Ideally, we'd like to get rid of all VLAs in the kernel and add -Wvla to
the build args: https://lkml.org/lkml/2018/3/7/621

This one is a simple case, since we don't actually need the VLA at all: we
can just iterate over the stripes twice, once to emit their names, and the
second time to emit status (i.e. trade memory for time). Since the number
of stripes is probably low, this is hopefully not that expensive.

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:18 -04:00
Qu Wenruo
e5c4cb9b1b dm log writes: record metadata flag for better flags record
So developer could distinguish data and metadata bios easier.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:17 -04:00
Milan Broz
e16b4f99f0 dm integrity: fail early if required HMAC key is not available
Since crypto API commit 9fa68f6200 ("crypto: hash - prevent using keyed
hashes without setting key") dm-integrity cannot use keyed algorithms
without the key being set.

The dm-integrity recognizes this too late (during use of HMAC), so it
allows creation and formatting of superblock, but the device is in fact
unusable.

Fix it by detecting the key requirement in integrity table constructor.

Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:16 -04:00
Wang Sheng-Hui
2d77dafe23 dm: remove unused macro DM_MOD_NAME_SIZE
Signed-off-by: Wang Sheng-Hui <shhuiw@foxmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:15 -04:00
Heinz Mauelshagen
afac6bd6d1 dm unstripe: remove unnecessary header includes
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:15 -04:00
Heinz Mauelshagen
91e065d8f2 dm unstripe: remove superfluous module init error path message
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Reviewed-by: Scott Bauer <Scott.Bauer@intel.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:14 -04:00
Heinz Mauelshagen
ba5dfbb712 dm unstripe: add "dm-unstriped" module alias
This target's kernel module being named dm-unstripe.ko doesn't allow
lvm2's DM module autoload capability to load the dm-unstripe.ko
because lvm2 looks for dm-unstriped.ko due to the target name being
"unstriped".

Add the "dm-unstriped" module alias to resolve this oversight.

NOTE: this isn't needed for the "striped" target, despite its source
file being named dm-stripe.c, because it is part of dm-mod.ko.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:13 -04:00
Heinz Mauelshagen
2ae600cd15 dm unstripe: support non-power-of-2 chunk size
Address "FIXME: must support non power of 2 chunk_size, dm-stripe.c does".

Bump target version to indicate change.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Tested-by: Scott Bauer <Scott.Bauer@intel.com>
Reviewed-by: Scott Bauer <Scott.Bauer@intel.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:12 -04:00
Mikulas Patocka
5059353df8 dm crypt: limit the number of allocated pages
dm-crypt consumes an excessive amount memory when the user attempts to
zero a dm-crypt device with "blkdiscard -z". The command "blkdiscard -z"
calls the BLKZEROOUT ioctl, it goes to the function __blkdev_issue_zeroout,
__blkdev_issue_zeroout sends a large amount of write bios that contain
the zero page as their payload.

For each incoming page, dm-crypt allocates another page that holds the
encrypted data, so when processing "blkdiscard -z", dm-crypt tries to
allocate the amount of memory that is equal to the size of the device.
This can trigger OOM killer or cause system crash.

Fix this by limiting the amount of memory that dm-crypt allocates to 2%
of total system memory. This limit is system-wide and is divided by the
number of active dm-crypt devices and each device receives an equal
share.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:11 -04:00
Mike Snitzer
1eb5fa849f dm: allow targets to return output from messages they are sent
Could be useful for a target to return stats or other information.
If a target does DMEMIT() anything to @result from its .message method
then it must return 1 to the caller.

Signed-off-By: Mike Snitzer <snitzer@redhat.com>
2018-04-03 15:04:10 -04:00
Dan Williams
976431b02c dax, dm: allow device-mapper to operate without dax support
Change device-mapper's DAX dependency to require the presence of at
least one DAX_DRIVER. This allows device-mapper to be built without
bringing the DAX core along which is especially wasteful when there are
no DAX drivers, like BLK_DEV_PMEM, configured.

Cc: Alasdair Kergon <agk@redhat.com>
Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-04-03 05:41:19 -07:00
Mike Snitzer
da5dadb4f1 dm: fix dropped return code from dm_get_bdev_for_ioctl
dm_get_bdev_for_ioctl()'s return of 0 or 1 must be the result from
prepare_ioctl (1 means the ioctl was issued to a partition, 0 means it
wasn't).  Unfortunately commit 519049afea ("dm: use blkdev_get rather
than bdgrab when issuing pass-through ioctl") reused the variable 'r'
to store the return from blkdev_get() that follows prepare_ioctl()
-- whereby dropping prepare_ioctl()'s result on the floor.

This can lead to an ioctl or persistent reservation being issued to a
partition going unnoticed, which implies the extra permission check for
CAP_SYS_RAWIO is skipped.

Fix this by using a different variable to store blkdev_get()'s return.

Fixes: 519049afea ("dm: use blkdev_get rather than bdgrab when issuing pass-through ioctl")
Reported-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2018-03-29 23:31:32 -04:00