Commit Graph

5678 Commits

Author SHA1 Message Date
Kent Overstreet
b330e6a49d md: convert to kvmalloc
The code really just wants a big flat buffer, so just do that.

Link: http://lkml.kernel.org/r/20181217131929.11727-3-kent.overstreet@gmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12 10:04:02 -07:00
Linus Torvalds
6cdc577a18 - Update bio-based DM core to always call blk_queue_split() and update
DM targets to properly advertise discard limits that blk_queue_split()
   looks at when dtermining to split discard.  Whereby allowing DM core's
   own 'split_discard_bios' to be removed.
 
 - Improve DM cache target to provide support for discard passdown to the
   origin device.
 
 - Introduce support to directly boot to a DM mapped device from init by
   using dm-mod.create= module param.  This eliminates the need for an
   elaborate initramfs that is otherwise needed to create DM devices.
   This feature's implementation has been worked on for quite some time
   (got up to v12) and is of particular interest to Android and other
   more embedded platforms (e.g. ARM).
 
 - Rate limit errors from the DM integrity target that were identified as
   the cause for recent NMI hangs due to console limitations.
 
 - Add sanity checks for user input to thin-pool and external snapshot
   creation.
 
 - Remove some unused leftover kmem caches from when old .request_fn
   request-based support was removed.
 
 - Various small cleanups and fixes to targets (e.g. typos, needless
   unlikely() annotations, use struct_size(), remove needless
   .direct_access method from dm-snapshot)
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Merge tag 'for-5.1/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Update bio-based DM core to always call blk_queue_split() and update
   DM targets to properly advertise discard limits that
   blk_queue_split() looks at when dtermining to split discard. Whereby
   allowing DM core's own 'split_discard_bios' to be removed.

 - Improve DM cache target to provide support for discard passdown to
   the origin device.

 - Introduce support to directly boot to a DM mapped device from init by
   using dm-mod.create= module param. This eliminates the need for an
   elaborate initramfs that is otherwise needed to create DM devices.

   This feature's implementation has been worked on for quite some time
   (got up to v12) and is of particular interest to Android and other
   more embedded platforms (e.g. ARM).

 - Rate limit errors from the DM integrity target that were identified
   as the cause for recent NMI hangs due to console limitations.

 - Add sanity checks for user input to thin-pool and external snapshot
   creation.

 - Remove some unused leftover kmem caches from when old .request_fn
   request-based support was removed.

 - Various small cleanups and fixes to targets (e.g. typos, needless
   unlikely() annotations, use struct_size(), remove needless
   .direct_access method from dm-snapshot)

* tag 'for-5.1/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm integrity: limit the rate of error messages
  dm snapshot: don't define direct_access if we don't support it
  dm cache: add support for discard passdown to the origin device
  dm writecache: fix typo in name for writeback_wq
  dm: add support to directly boot to a mapped device
  dm thin: add sanity checks to thin-pool and external snapshot creation
  dm block manager: remove redundant unlikely annotation
  dm verity fec: remove redundant unlikely annotation
  dm integrity: remove redundant unlikely annotation
  dm: always call blk_queue_split() in dm_process_bio()
  dm: fix to_sector() for 32bit
  dm switch: use struct_size() in kzalloc()
  dm: remove unused _rq_tio_cache and _rq_cache
  dm: eliminate 'split_discard_bios' flag from DM target interface
  dm: update dm_process_bio() to split bio if in ->make_request_fn()
2019-03-09 17:40:27 -08:00
Linus Torvalds
80201fe175 for-5.1/block-20190302
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Merge tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:
 "Not a huge amount of changes in this round, the biggest one is that we
  finally have Mings multi-page bvec support merged. Apart from that,
  this pull request contains:

   - Small series that avoids quiescing the queue for sysfs changes that
     match what we currently have (Aleksei)

   - Series of bcache fixes (via Coly)

   - Series of lightnvm fixes (via Mathias)

   - NVMe pull request from Christoph. Nothing major, just SPDX/license
     cleanups, RR mp policy (Hannes), and little fixes (Bart,
     Chaitanya).

   - BFQ series (Paolo)

   - Save blk-mq cpu -> hw queue mapping, removing a pointer indirection
     for the fast path (Jianchao)

   - fops->iopoll() added for async IO polling, this is a feature that
     the upcoming io_uring interface will use (Christoph, me)

   - Partition scan loop fixes (Dongli)

   - mtip32xx conversion from managed resource API (Christoph)

   - cdrom registration race fix (Guenter)

   - MD pull from Song, two minor fixes.

   - Various documentation fixes (Marcos)

   - Multi-page bvec feature. This brings a lot of nice improvements
     with it, like more efficient splitting, larger IOs can be supported
     without growing the bvec table size, and so on. (Ming)

   - Various little fixes to core and drivers"

* tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block: (117 commits)
  block: fix updating bio's front segment size
  block: Replace function name in string with __func__
  nbd: propagate genlmsg_reply return code
  floppy: remove set but not used variable 'q'
  null_blk: fix checking for REQ_FUA
  block: fix NULL pointer dereference in register_disk
  fs: fix guard_bio_eod to check for real EOD errors
  blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->map
  block: optimize bvec iteration in bvec_iter_advance
  block: introduce mp_bvec_for_each_page() for iterating over page
  block: optimize blk_bio_segment_split for single-page bvec
  block: optimize __blk_segment_map_sg() for single-page bvec
  block: introduce bvec_nth_page()
  iomap: wire up the iopoll method
  block: add bio_set_polled() helper
  block: wire up block device iopoll method
  fs: add an iopoll method to struct file_operations
  loop: set GENHD_FL_NO_PART_SCAN after blkdev_reread_part()
  loop: do not print warn message if partition scan is successful
  block: bounce: make sure that bvec table is updated
  ...
2019-03-08 14:12:17 -08:00
Mikulas Patocka
2255574468 dm integrity: limit the rate of error messages
When using dm-integrity underneath md-raid, some tests with raid
auto-correction trigger large amounts of integrity failures - and all
these failures print an error message. These messages can bring the
system to a halt if the system is using serial console.

Fix this by limiting the rate of error messages - it improves the speed
of raid recovery and avoids the hang.

Fixes: 7eada909bf ("dm: add integrity target")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-06 09:03:00 -05:00
Mikulas Patocka
c439ca69d5 dm snapshot: don't define direct_access if we don't support it
Don't define a direct_access function that fails, dm_dax_direct_access
already fails with -EIO if the pointer is zero;

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:52 -05:00
Mike Snitzer
de7180ff90 dm cache: add support for discard passdown to the origin device
DM cache now defaults to passing discards down to the origin device.
User may disable this using the "no_discard_passdown" feature when
creating the cache device.

If the cache's underlying origin device doesn't support discards then
passdown is disabled (with warning).  Similarly, if the underlying
origin device's max_discard_sectors is less than a cache block discard
passdown will be disabled (this is required because sizing of the cache
internal discard bitset depends on it).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:52 -05:00
Huaisheng Ye
f87e033b3b dm writecache: fix typo in name for writeback_wq
The workqueue's name should be "writecache-writeback" instead of
"writecache-writeabck".

Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:51 -05:00
Helen Koike
6bbc923dfc dm: add support to directly boot to a mapped device
Add a "create" module parameter, which allows device-mapper targets to
be configured at boot time. This enables early use of DM targets in the
boot process (as the root device or otherwise) without the need of an
initramfs.

The syntax used in the boot param is based on the concise format from
the dmsetup tool to follow the rule of least surprise:

	dmsetup table --concise /dev/mapper/lroot

Which is:
	dm-mod.create=<name>,<uuid>,<minor>,<flags>,<table>[,<table>+][;<name>,<uuid>,<minor>,<flags>,<table>[,<table>+]+]

Where,
	<name>		::= The device name.
	<uuid>		::= xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx | ""
	<minor>		::= The device minor number | ""
	<flags>		::= "ro" | "rw"
	<table>		::= <start_sector> <num_sectors> <target_type> <target_args>
	<target_type>	::= "verity" | "linear" | ...

For example, the following could be added in the boot parameters:
dm-mod.create="lroot,,,rw, 0 4096 linear 98:16 0, 4096 4096 linear 98:32 0" root=/dev/dm-0

Only the targets that were tested are allowed and the ones that don't
change any block device when the device is create as read-only. For
example, mirror and cache targets are not allowed. The rationale behind
this is that if the user makes a mistake, choosing the wrong device to
be the mirror or the cache can corrupt data.

The only targets initially allowed are:
* crypt
* delay
* linear
* snapshot-origin
* striped
* verity

Co-developed-by: Will Drewry <wad@chromium.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:50 -05:00
Jason Cai (Xiang Feng)
70de2cbda8 dm thin: add sanity checks to thin-pool and external snapshot creation
Invoking dm_get_device() twice on the same device path with different
modes is dangerous.  Because in that case, upgrade_mode() will alloc a
new 'dm_dev' and free the old one, which may be referenced by a previous
caller.  Dereferencing the dangling pointer will trigger kernel NULL
pointer dereference.

The following two cases can reproduce this issue.  Actually, they are
invalid setups that must be disallowed, e.g.:

1. Creating a thin-pool with read_only mode, and the same device as
both metadata and data.

dmsetup create thinp --table \
    "0 41943040 thin-pool /dev/vdb /dev/vdb 128 0 1 read_only"

BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
...
Call Trace:
 new_read+0xfb/0x110 [dm_bufio]
 dm_bm_read_lock+0x43/0x190 [dm_persistent_data]
 ? kmem_cache_alloc_trace+0x15c/0x1e0
 __create_persistent_data_objects+0x65/0x3e0 [dm_thin_pool]
 dm_pool_metadata_open+0x8c/0xf0 [dm_thin_pool]
 pool_ctr.cold.79+0x213/0x913 [dm_thin_pool]
 ? realloc_argv+0x50/0x70 [dm_mod]
 dm_table_add_target+0x14e/0x330 [dm_mod]
 table_load+0x122/0x2e0 [dm_mod]
 ? dev_status+0x40/0x40 [dm_mod]
 ctl_ioctl+0x1aa/0x3e0 [dm_mod]
 dm_ctl_ioctl+0xa/0x10 [dm_mod]
 do_vfs_ioctl+0xa2/0x600
 ? handle_mm_fault+0xda/0x200
 ? __do_page_fault+0x26c/0x4f0
 ksys_ioctl+0x60/0x90
 __x64_sys_ioctl+0x16/0x20
 do_syscall_64+0x55/0x150
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

2. Creating a external snapshot using the same thin-pool device.

dmsetup create thinp --table \
    "0 41943040 thin-pool /dev/vdc /dev/vdb 128 0 2 ignore_discard"
dmsetup message /dev/mapper/thinp 0 "create_thin 0"
dmsetup create snap --table \
            "0 204800 thin /dev/mapper/thinp 0 /dev/mapper/thinp"

BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
...
Call Trace:
? __alloc_pages_nodemask+0x13c/0x2e0
retrieve_status+0xa5/0x1f0 [dm_mod]
? dm_get_live_or_inactive_table.isra.7+0x20/0x20 [dm_mod]
 table_status+0x61/0xa0 [dm_mod]
 ctl_ioctl+0x1aa/0x3e0 [dm_mod]
 dm_ctl_ioctl+0xa/0x10 [dm_mod]
 do_vfs_ioctl+0xa2/0x600
 ksys_ioctl+0x60/0x90
 ? ksys_write+0x4f/0xb0
 __x64_sys_ioctl+0x16/0x20
 do_syscall_64+0x55/0x150
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Jason Cai (Xiang Feng) <jason.cai@linux.alibaba.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:49 -05:00
Chengguang Xu
5941c621dc dm block manager: remove redundant unlikely annotation
unlikely has already included in IS_ERR(),
so just remove redundant unlikely annotation.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:48 -05:00
Chengguang Xu
821b40da4d dm verity fec: remove redundant unlikely annotation
unlikely has already included in IS_ERR(),
so just remove redundant unlikely annotation.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:48 -05:00
Chengguang Xu
5e3d0e3706 dm integrity: remove redundant unlikely annotation
unlikely has already included in IS_ERR(),
so just remove redundant unlikely annotation.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:47 -05:00
Mike Snitzer
effd58c95f dm: always call blk_queue_split() in dm_process_bio()
Do not just call blk_queue_split() if the bio is_abnormal_io().

Fixes: 568c73a355 ("dm: update dm_process_bio() to split bio if in ->make_request_fn()")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:53:32 -05:00
Gustavo A. R. Silva
d2832376b6 dm switch: use struct_size() in kzalloc()
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
    int stuff;
    void *entry[];
};

instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:48:51 -05:00
Mike Snitzer
e689fbab3d dm: remove unused _rq_tio_cache and _rq_cache
Also move dm_rq_target_io structure definition from dm-rq.h to dm-rq.c

Fixes: 6a23e05c2f ("dm: remove legacy request-based IO path")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-03-05 14:48:50 -05:00
Mike Snitzer
61697a6abd dm: eliminate 'split_discard_bios' flag from DM target interface
There is no need to have DM core split discards on behalf of a DM target
now that blk_queue_split() handles splitting discards based on the
queue_limits.  A DM target just needs to set max_discard_sectors,
discard_granularity, etc, in queue_limits.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-02-20 23:24:55 -05:00
Mike Snitzer
568c73a355 dm: update dm_process_bio() to split bio if in ->make_request_fn()
Must call blk_queue_split() otherwise queue_limits for abnormal requests
(e.g. discard, writesame, etc) won't be imposed.

In addition, add dm_queue_split() to simplify DM specific splitting that
is needed for targets that impose ti->max_io_len.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-02-19 12:25:00 -05:00
Linus Torvalds
24f0a48743 for-linus-20190215
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Merge tag 'for-linus-20190215' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - Ensure we insert into the hctx dispatch list, if a request is marked
   as DONTPREP (Jianchao)

 - NVMe pull request, single missing unlock on error fix (Keith)

 - MD pull request, single fix for a potentially data corrupting issue
   (Nate)

 - Floppy check_events regression fix (Yufen)

* tag 'for-linus-20190215' of git://git.kernel.dk/linux-block:
  md/raid1: don't clear bitmap bits on interrupted recovery.
  floppy: check_events callback should not return a negative number
  nvme-pci: add missing unlock for reset error
  blk-mq: insert rq with DONTPREP to hctx dispatch list when requeue
2019-02-15 09:12:28 -08:00
Jens Axboe
6fb845f0e7 Linux 5.0-rc6
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Merge tag 'v5.0-rc6' into for-5.1/block

Pull in 5.0-rc6 to avoid a dumb merge conflict with fs/iomap.c.
This is needed since io_uring is now based on the block branch,
to avoid a conflict between the multi-page bvecs and the bits
of io_uring that touch the core block parts.

* tag 'v5.0-rc6': (525 commits)
  Linux 5.0-rc6
  x86/mm: Make set_pmd_at() paravirt aware
  MAINTAINERS: Update the ocores i2c bus driver maintainer, etc
  blk-mq: remove duplicated definition of blk_mq_freeze_queue
  Blk-iolatency: warn on negative inflight IO counter
  blk-iolatency: fix IO hang due to negative inflight counter
  MAINTAINERS: unify reference to xen-devel list
  x86/mm/cpa: Fix set_mce_nospec()
  futex: Handle early deadlock return correctly
  futex: Fix barrier comment
  net: dsa: b53: Fix for failure when irq is not defined in dt
  blktrace: Show requests without sector
  mips: cm: reprime error cause
  mips: loongson64: remove unreachable(), fix loongson_poweroff().
  sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach()
  geneve: should not call rt6_lookup() when ipv6 was disabled
  KVM: nVMX: unconditionally cancel preemption timer in free_nested (CVE-2019-7221)
  KVM: x86: work around leak of uninitialized stack contents (CVE-2019-7222)
  kvm: fix kvm_ioctl_create_device() reference counting (CVE-2019-6974)
  signal: Better detection of synchronous signals
  ...
2019-02-15 08:43:59 -07:00
Ming Lei
56d18f62f5 block: kill BLK_MQ_F_SG_MERGE
QUEUE_FLAG_NO_SG_MERGE has been killed, so kill BLK_MQ_F_SG_MERGE too.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-15 08:40:12 -07:00
Ming Lei
2705c93742 block: kill QUEUE_FLAG_NO_SG_MERGE
Since bdced438ac ("block: setup bi_phys_segments after splitting"),
physical segment number is mainly figured out in blk_queue_split() for
fast path, and the flag of BIO_SEG_VALID is set there too.

Now only blk_recount_segments() and blk_recalc_rq_segments() use this
flag.

Basically blk_recount_segments() is bypassed in fast path given BIO_SEG_VALID
is set in blk_queue_split().

For another user of blk_recalc_rq_segments():

- run in partial completion branch of blk_update_request, which is an unusual case

- run in blk_cloned_rq_check_limits(), still not a big problem if the flag is killed
since dm-rq is the only user.

Multi-page bvec is enabled now, not doing S/G merging is rather pointless with the
current setup of the I/O path, as it isn't going to save you a significant amount
of cycles.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-15 08:40:12 -07:00
Ming Lei
6dc4f100c1 block: allow bio_for_each_segment_all() to iterate over multi-page bvec
This patch introduces one extra iterator variable to bio_for_each_segment_all(),
then we can allow bio_for_each_segment_all() to iterate over multi-page bvec.

Given it is just one mechannical & simple change on all bio_for_each_segment_all()
users, this patch does tree-wide change in one single patch, so that we can
avoid to use a temporary helper for this conversion.

Reviewed-by: Omar Sandoval <osandov@fb.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>
2019-02-15 08:40:11 -07:00
Ming Lei
2e1f4f4d24 bcache: avoid to use bio_for_each_segment_all() in bch_bio_alloc_pages()
bch_bio_alloc_pages() is always called on one new bio, so it is safe
to access the bvec table directly. Given it is the only kind of this
case, open code the bvec table access since bio_for_each_segment_all()
will be changed to support for iterating over multipage bvec.

Acked-by: Coly Li <colyli@suse.de>
Reviewed-by: Omar Sandoval <osandov@fb.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>
2019-02-15 08:40:11 -07:00
Nikos Tsironis
4ae280b4ee dm thin: fix bug where bio that overwrites thin block ignores FUA
When provisioning a new data block for a virtual block, either because
the block was previously unallocated or because we are breaking sharing,
if the whole block of data is being overwritten the bio that triggered
the provisioning is issued immediately, skipping copying or zeroing of
the data block.

When this bio completes the new mapping is inserted in to the pool's
metadata by process_prepared_mapping(), where the bio completion is
signaled to the upper layers.

This completion is signaled without first committing the metadata.  If
the bio in question has the REQ_FUA flag set and the system crashes
right after its completion and before the next metadata commit, then the
write is lost despite the REQ_FUA flag requiring that I/O completion for
this request must only be signaled after the data has been committed to
non-volatile storage.

Fix this by deferring the completion of overwrite bios, with the REQ_FUA
flag set, until after the metadata has been committed.

Cc: stable@vger.kernel.org
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-02-14 19:02:29 -05:00
Nate Dailey
dfcc34c99f md/raid1: don't clear bitmap bits on interrupted recovery.
sync_request_write no longer submits writes to a Faulty device. This has
the unfortunate side effect that bitmap bits can be incorrectly cleared
if a recovery is interrupted (previously, end_sync_write would have
prevented this). This means the next recovery may not copy everything
it should, potentially corrupting data.

Add a function for doing the proper md_bitmap_end_sync, called from
end_sync_write and the Faulty case in sync_request_write.

backport note to 4.14: s/md_bitmap_end_sync/bitmap_end_sync
Cc: stable@vger.kernel.org 4.14+
Fixes: 0c9d5b127f ("md/raid1: avoid reusing a resync bio after error handling.")
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Tested-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Nate Dailey <nate.dailey@stratus.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-02-12 14:06:58 -08:00
Mikulas Patocka
ff0c129d3b dm crypt: don't overallocate the integrity tag space
bio_sectors() returns the value in the units of 512-byte sectors (no
matter what the real sector size of the device).  dm-crypt multiplies
bio_sectors() by on_disk_tag_size to calculate the space allocated for
integrity tags.  If dm-crypt is running with sector size larger than
512b, it allocates more data than is needed.

Device Mapper trims the extra space when passing the bio to
dm-integrity, so this bug didn't result in any visible misbehavior.
But it must be fixed to avoid wasteful memory allocation for the block
integrity payload.

Fixes: ef43aa3806 ("dm crypt: add cryptographic data integrity protection (authenticated encryption)")
Cc: stable@vger.kernel.org # 4.12+
Reported-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-02-11 12:06:48 -05:00
Coly Li
dc7292a5bc bcache: use (REQ_META|REQ_PRIO) to indicate bio for metadata
In 'commit 752f66a75a ("bcache: use REQ_PRIO to indicate bio for
metadata")' REQ_META is replaced by REQ_PRIO to indicate metadata bio.
This assumption is not always correct, e.g. XFS uses REQ_META to mark
metadata bio other than REQ_PRIO. This is why Nix noticed that bcache
does not cache metadata for XFS after the above commit.

Thanks to Dave Chinner, he explains the difference between REQ_META and
REQ_PRIO from view of file system developer. Here I quote part of his
explanation from mailing list,
   REQ_META is used for metadata. REQ_PRIO is used to communicate to
   the lower layers that the submitter considers this IO to be more
   important that non REQ_PRIO IO and so dispatch should be expedited.

   IOWs, if the filesystem considers metadata IO to be more important
   that user data IO, then it will use REQ_PRIO | REQ_META rather than
   just REQ_META.

Then it seems bios with REQ_META or REQ_PRIO should both be cached for
performance optimation, because they are all probably low I/O latency
demand by upper layer (e.g. file system).

So in this patch, when we want to decide whether to bypass the cache,
REQ_META and REQ_PRIO are both checked. Then both metadata and
high priority I/O requests will be handled properly.

Reported-by: Nix <nix@esperi.org.uk>
Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Andre Noll <maan@tuebingen.mpg.de>
Tested-by: Nix <nix@esperi.org.uk>
Cc: stable@vger.kernel.org
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:33 -07:00
Coly Li
a91fbda49f bcache: fix input overflow to cache set sysfs file io_error_halflife
Cache set sysfs entry io_error_halflife is used to set c->error_decay.
c->error_decay is in type unsigned int, and it is converted by
strtoul_or_return(), therefore overflow to c->error_decay is possible
for a large input value.

This patch fixes the overflow by using strtoul_safe_clamp() to convert
input string to an unsigned long value in range [0, UINT_MAX], then
divides by 88 and set it to c->error_decay.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:33 -07:00
Coly Li
b15008403b bcache: fix input overflow to cache set io_error_limit
c->error_limit is in type unsigned int, it is set via cache set sysfs
file io_error_limit. Inside the bcache code, input string is converted
by strtoul_or_return() and set the converted value to c->error_limit.

Because the converted value is unsigned long, and c->error_limit is
unsigned int, if the input is large enought, overflow will happen to
c->error_limit.

This patch uses sysfs_strtoul_clamp() to convert input string, and set
the range in [0, UINT_MAX] to avoid the potential overflow.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
453745fbbe bcache: fix input overflow to journal_delay_ms
c->journal_delay_ms is in type unsigned short, it is set via sysfs
interface and converted by sysfs_strtoul() from input string to
unsigned short value. Therefore overflow to unsigned short might be
happen when the converted value exceed USHRT_MAX. e.g. writing
65536 into sysfs file journal_delay_ms, c->journal_delay_ms is set to
0.

This patch uses sysfs_strtoul_clamp() to convert the input string and
limit value range in [0, USHRT_MAX], to avoid the input overflow.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
dab71b2db9 bcache: fix input overflow to writeback_rate_minimum
dc->writeback_rate_minimum is type unsigned integer variable, it is set
via sysfs interface, and converte from input string to unsigned integer
by d_strtoul_nonzero(). When the converted input value is larger than
UINT_MAX, overflow to unsigned integer happens.

This patch fixes the overflow by using sysfs_strotoul_clamp() to
convert input string and limit the value in range [1, UINT_MAX], then
the overflow can be avoided.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
5b5fd3c94e bcache: fix potential div-zero error of writeback_rate_p_term_inverse
Current code already uses d_strtoul_nonzero() to convert input string
to an unsigned integer, to make sure writeback_rate_p_term_inverse
won't be zero value. But overflow may happen when converting input
string to an unsigned integer value by d_strtoul_nonzero(), then
dc->writeback_rate_p_term_inverse can still be set to 0 even if the
sysfs file input value is not zero, e.g. 4294967296 (a.k.a UINT_MAX+1).

If dc->writeback_rate_p_term_inverse is set to 0, it might cause a
dev-zero error in following code from __update_writeback_rate(),
	int64_t proportional_scaled =
		div_s64(error, dc->writeback_rate_p_term_inverse);

This patch replaces d_strtoul_nonzero() by sysfs_strtoul_clamp() and
limit the value range in [1, UINT_MAX]. Then the unsigned integer
overflow and dev-zero error can be avoided.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
c3b75a2199 bcache: fix potential div-zero error of writeback_rate_i_term_inverse
dc->writeback_rate_i_term_inverse can be set via sysfs interface. It is
in type unsigned int, and convert from input string by d_strtoul(). The
problem is d_strtoul() does not check valid range of the input, if
4294967296 is written into sysfs file writeback_rate_i_term_inverse,
an overflow of unsigned integer will happen and value 0 is set to
dc->writeback_rate_i_term_inverse.

In writeback.c:__update_writeback_rate(), there are following lines of
code,
      integral_scaled = div_s64(dc->writeback_rate_integral,
                      dc->writeback_rate_i_term_inverse);
If dc->writeback_rate_i_term_inverse is set to 0 via sysfs interface,
a div-zero error might be triggered in the above code.

Therefore we need to add a range limitation in the sysfs interface,
this is what this patch does, use sysfs_stroul_clamp() to replace
d_strtoul() and restrict the input range in [1, UINT_MAX].

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
369d21a73a bcache: fix input overflow to writeback_delay
Sysfs file writeback_delay is used to configure dc->writeback_delay
which is type unsigned int. But bcache code uses sysfs_strtoul() to
convert the input string, therefore it might be overflowed if the input
value is too large. E.g. input value is 4294967296 but indeed 0 is
set to dc->writeback_delay.

This patch uses sysfs_strtoul_clamp() to convert the input string and
set the result value range in [0, UINT_MAX] to avoid such unsigned
integer overflow.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
f5c0b95d2e bcache: use sysfs_strtoul_bool() to set bit-field variables
When setting bcache parameters via sysfs, there are some variables are
defined as bit-field value. Current bcache code in sysfs.c uses either
d_strtoul() or sysfs_strtoul() to convert the input string to unsigned
integer value and set it to the corresponded bit-field value.

The problem is, the bit-field value only takes the lowest bit of the
converted value. If input is 2, the expected value (like bool value)
of the bit-field value should be 1, but indeed it is 0.

The following sysfs files for bit-field variables have such problem,
	bypass_torture_test,	for dc->bypass_torture_test
	writeback_metadata,	for dc->writeback_metadata
	writeback_running,	for dc->writeback_running
	verify,			for c->verify
	key_merging_disabled,	for c->key_merging_disabled
	gc_always_rewrite,	for c->gc_always_rewrite
	btree_shrinker_disabled,for c->shrinker_disabled
	copy_gc_enabled,	for c->copy_gc_enabled

This patch uses sysfs_strtoul_bool() to set such bit-field variables,
then if the converted value is non-zero, the bit-field variables will
be set to 1, like setting a bool value like expensive_debug_checks.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
e4db37fb69 bcache: add sysfs_strtoul_bool() for setting bit-field variables
When setting bool values via sysfs interface, e.g. writeback_metadata,
if writing 1 into writeback_metadata file, dc->writeback_metadata is
set to 1, but if writing 2 into the file, dc->writeback_metadata is
0. This is misleading, a better result should be 1 for all non-zero
input value.

It is because dc->writeback_metadata is a bit-field variable, and
current code simply use d_strtoul() to convert a string into integer
and takes the lowest bit value. To fix such error, we need a routine
to convert the input string into unsigned integer, and set target
variable to 1 if the converted integer is non-zero.

This patch introduces a new macro called sysfs_strtoul_bool(), it can
be used to convert input string into bool value, we can use it to set
bool value for bit-field vairables.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
8c27a3953e bcache: fix input overflow to sequential_cutoff
People may set sequential_cutoff of a cached device via sysfs file,
but current code does not check input value overflow. E.g. if value
4294967295 (UINT_MAX) is written to file sequential_cutoff, its value
is 4GB, but if 4294967296 (UINT_MAX + 1) is written into, its value
will be 0. This is an unexpected behavior.

This patch replaces d_strtoi_h() by sysfs_strtoul_clamp() to convert
input string to unsigned integer value, and limit its range in
[0, UINT_MAX]. Then the input overflow can be fixed.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:32 -07:00
Coly Li
f54478c6e2 bcache: fix input integer overflow of congested threshold
Cache set congested threshold values congested_read_threshold_us and
congested_write_threshold_us can be set via sysfs interface. These
two values are 'unsigned int' type, but sysfs interface uses strtoul
to convert input string. So if people input a large number like
9999999999, the value indeed set is 1410065407, which is not expected
behavior.

This patch replaces sysfs_strtoul() by sysfs_strtoul_clamp() when
convert input string to unsigned int value, and set value range in
[0, UINT_MAX], to avoid the above integer overflow errors.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Coly Li
596b5a5dd1 bcache: improve sysfs_strtoul_clamp()
Currently sysfs_strtoul_clamp() is defined as,
 82 #define sysfs_strtoul_clamp(file, var, min, max)                   \
 83 do {                                                               \
 84         if (attr == &sysfs_ ## file)                               \
 85                 return strtoul_safe_clamp(buf, var, min, max)      \
 86                         ?: (ssize_t) size;                         \
 87 } while (0)

The problem is, if bit width of var is less then unsigned long, min and
max may not protect var from integer overflow, because overflow happens
in strtoul_safe_clamp() before checking min and max.

To fix such overflow in sysfs_strtoul_clamp(), to make min and max take
effect, this patch adds an unsigned long variable, and uses it to macro
strtoul_safe_clamp() to convert an unsigned long value in range defined
by [min, max]. Then assign this value to var. By this method, if bit
width of var is less than unsigned long, integer overflow won't happen
before min and max are checking.

Now sysfs_strtoul_clamp() can properly handle smaller data type like
unsigned int, of cause min and max should be defined in range of
unsigned int too.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Tang Junhui
58ac323084 bcache: treat stale && dirty keys as bad keys
Stale && dirty keys can be produced in the follow way:
After writeback in write_dirty_finish(), dirty keys k1 will
replace by clean keys k2
==>ret = bch_btree_insert(dc->disk.c, &keys, NULL, &w->key);
==>btree_insert_fn(struct btree_op *b_op, struct btree *b)
==>static int bch_btree_insert_node(struct btree *b,
       struct btree_op *op,
       struct keylist *insert_keys,
       atomic_t *journal_ref,
Then two steps:
A) update k1 to k2 in btree node memory;
   bch_btree_insert_keys(b, op, insert_keys, replace_key)
B) Write the bset(contains k2) to cache disk by a 30s delay work
   bch_btree_leaf_dirty(b, journal_ref).
But before the 30s delay work write the bset to cache device,
these things happened:
A) GC works, and reclaim the bucket k2 point to;
B) Allocator works, and invalidate the bucket k2 point to,
   and increase the gen of the bucket, and place it into free_inc
   fifo;
C) Until now, the 30s delay work still does not finish work,
   so in the disk, the key still is k1, it is dirty and stale
   (its gen is smaller than the gen of the bucket). and then the
   machine power off suddenly happens;
D) When the machine power on again, after the btree reconstruction,
   the stale dirty key appear.

In bch_extent_bad(), when expensive_debug_checks is off, it would
treat the dirty key as good even it is stale keys, and it would
cause bellow probelms:
A) In read_dirty() it would cause machine crash:
   BUG_ON(ptr_stale(dc->disk.c, &w->key, 0));
B) It could be worse when reads hits stale dirty keys, it would
   read old incorrect data.

This patch tolerate the existence of these stale && dirty keys,
and treat them as bad key in bch_extent_bad().

(Coly Li: fix indent which was modified by sender's email client)

Signed-off-by: Tang Junhui <tang.junhui.linux@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Colin Ian King
e8cf978dff bcache: fix indentation issue, remove tabs on a hunk of code
There is a hunk of code that is indented one level too deep, fix this
by removing the extra tabs.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Coly Li
d4610456cf bcache: export backing_dev_uuid via sysfs
When there are multiple bcache devices, after a reboot the name of
bcache devices may change (e.g. current /dev/bcache1 was /dev/bcache0
before reboot). Therefore we need the backing device UUID (sb.uuid) to
identify each bcache device.

Backing device uuid can be found by program bcache-super-show, but
directly exporting backing_dev_uuid by sysfs file
/sys/block/bcache<?>/bcache/backing_dev_uuid is a much simpler method.

With backing_dev_uuid, and partition uuids from /dev/disk/by-partuuid/,
now we can identify each bcache device and its partitions conveniently.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Coly Li
926d19465b bcache: export backing_dev_name via sysfs
This patch export dc->backing_dev_name to sysfs file
/sys/block/bcache<?>/bcache/backing_dev_name, then people or user space
tools may know the backing device name of this bcache device.

Of cause it can be done by parsing sysfs links, but this method can be
much simpler to find the link between bcache device and backing device.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Coly Li
83ff9318c4 bcache: not use hard coded memset size in bch_cache_accounting_clear()
In stats.c:bch_cache_accounting_clear(), a hard coded number '7' is
used in memset(). It is because in struct cache_stats, there are 7
atomic_t type members. This is not good when new members added into
struct stats, the hard coded number will only clear part of memory.

This patch replaces 'sizeof(unsigned long) * 7' by more generic
'sizeof(struct cache_stats))', to avoid potential error if new
member added into struct cache_stats.

Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Daniel Axtens
9951379b0c bcache: never writeback a discard operation
Some users see panics like the following when performing fstrim on a
bcached volume:

[  529.803060] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[  530.183928] #PF error: [normal kernel read fault]
[  530.412392] PGD 8000001f42163067 P4D 8000001f42163067 PUD 1f42168067 PMD 0
[  530.750887] Oops: 0000 [#1] SMP PTI
[  530.920869] CPU: 10 PID: 4167 Comm: fstrim Kdump: loaded Not tainted 5.0.0-rc1+ #3
[  531.290204] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 12/27/2015
[  531.693137] RIP: 0010:blk_queue_split+0x148/0x620
[  531.922205] Code: 60 38 89 55 a0 45 31 db 45 31 f6 45 31 c9 31 ff 89 4d 98 85 db 0f 84 7f 04 00 00 44 8b 6d 98 4c 89 ee 48 c1 e6 04 49 03 70 78 <8b> 46 08 44 8b 56 0c 48
8b 16 44 29 e0 39 d8 48 89 55 a8 0f 47 c3
[  532.838634] RSP: 0018:ffffb9b708df39b0 EFLAGS: 00010246
[  533.093571] RAX: 00000000ffffffff RBX: 0000000000046000 RCX: 0000000000000000
[  533.441865] RDX: 0000000000000200 RSI: 0000000000000000 RDI: 0000000000000000
[  533.789922] RBP: ffffb9b708df3a48 R08: ffff940d3b3fdd20 R09: 0000000000000000
[  534.137512] R10: ffffb9b708df3958 R11: 0000000000000000 R12: 0000000000000000
[  534.485329] R13: 0000000000000000 R14: 0000000000000000 R15: ffff940d39212020
[  534.833319] FS:  00007efec26e3840(0000) GS:ffff940d1f480000(0000) knlGS:0000000000000000
[  535.224098] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  535.504318] CR2: 0000000000000008 CR3: 0000001f4e256004 CR4: 00000000001606e0
[  535.851759] Call Trace:
[  535.970308]  ? mempool_alloc_slab+0x15/0x20
[  536.174152]  ? bch_data_insert+0x42/0xd0 [bcache]
[  536.403399]  blk_mq_make_request+0x97/0x4f0
[  536.607036]  generic_make_request+0x1e2/0x410
[  536.819164]  submit_bio+0x73/0x150
[  536.980168]  ? submit_bio+0x73/0x150
[  537.149731]  ? bio_associate_blkg_from_css+0x3b/0x60
[  537.391595]  ? _cond_resched+0x1a/0x50
[  537.573774]  submit_bio_wait+0x59/0x90
[  537.756105]  blkdev_issue_discard+0x80/0xd0
[  537.959590]  ext4_trim_fs+0x4a9/0x9e0
[  538.137636]  ? ext4_trim_fs+0x4a9/0x9e0
[  538.324087]  ext4_ioctl+0xea4/0x1530
[  538.497712]  ? _copy_to_user+0x2a/0x40
[  538.679632]  do_vfs_ioctl+0xa6/0x600
[  538.853127]  ? __do_sys_newfstat+0x44/0x70
[  539.051951]  ksys_ioctl+0x6d/0x80
[  539.212785]  __x64_sys_ioctl+0x1a/0x20
[  539.394918]  do_syscall_64+0x5a/0x110
[  539.568674]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

We have observed it where both:
1) LVM/devmapper is involved (bcache backing device is LVM volume) and
2) writeback cache is involved (bcache cache_mode is writeback)

On one machine, we can reliably reproduce it with:

 # echo writeback > /sys/block/bcache0/bcache/cache_mode
   (not sure whether above line is required)
 # mount /dev/bcache0 /test
 # for i in {0..10}; do
	file="$(mktemp /test/zero.XXX)"
	dd if=/dev/zero of="$file" bs=1M count=256
	sync
	rm $file
    done
  # fstrim -v /test

Observing this with tracepoints on, we see the following writes:

fstrim-18019 [022] .... 91107.302026: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 4260112 + 196352 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302050: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 4456464 + 262144 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302075: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 4718608 + 81920 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302094: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 5324816 + 180224 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302121: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 5505040 + 262144 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302145: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 5767184 + 81920 hit 0 bypass 1
fstrim-18019 [022] .... 91107.308777: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 6373392 + 180224 hit 1 bypass 0
<crash>

Note the final one has different hit/bypass flags.

This is because in should_writeback(), we were hitting a case where
the partial stripe condition was returning true and so
should_writeback() was returning true early.

If that hadn't been the case, it would have hit the would_skip test, and
as would_skip == s->iop.bypass == true, should_writeback() would have
returned false.

Looking at the git history from 'commit 72c270612b ("bcache: Write out
full stripes")', it looks like the idea was to optimise for raid5/6:

       * If a stripe is already dirty, force writes to that stripe to
	 writeback mode - to help build up full stripes of dirty data

To fix this issue, make sure that should_writeback() on a discard op
never returns true.

More details of debugging:
https://www.spinics.net/lists/linux-bcache/msg06996.html

Previous reports:
 - https://bugzilla.kernel.org/show_bug.cgi?id=201051
 - https://bugzilla.kernel.org/show_bug.cgi?id=196103
 - https://www.spinics.net/lists/linux-bcache/msg06885.html

(Coly Li: minor modification to follow maximum 75 chars per line rule)

Cc: Kent Overstreet <koverstreet@google.com>
Cc: stable@vger.kernel.org
Fixes: 72c270612b ("bcache: Write out full stripes")
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-02-09 07:18:31 -07:00
Mike Snitzer
fa8db4948f dm: don't use bio_trim() afterall
bio_trim() has an early return, which makes it _not_ idempotent, if the
offset is 0 and the bio's bi_size already matches the requested size.
Prior to DM, all users of bio_trim() were fine with this.  But DM has
exposed the fact that bio_trim()'s early return is incompatible with a
cloned bio whose integrity payload must be trimmed via
bio_integrity_trim().

Fix this by reverting DM back to doing the equivalent of bio_trim() but
in an idempotent manner (so bio_integrity_trim is always performed).

Follow-on work is needed to assess what benefit bio_trim()'s early
return is providing to its existing callers.

Reported-by: Milan Broz <gmazyland@gmail.com>
Fixes: 57c36519e4 ("dm: fix clone_bio() to trigger blk_recount_segments()")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-02-06 17:24:37 -05:00
Mikulas Patocka
645efa84f6 dm: add memory barrier before waitqueue_active
Block core changes to switch bio-based IO accounting to be percpu had a
side-effect of altering DM core to now rely on calling waitqueue_active
(in both bio-based and request-based) to check if another task is in
dm_wait_for_completion().

A memory barrier is needed before calling waitqueue_active().  DM core
doesn't piggyback on a preceding memory barrier so it must explicitly
use its own.

For more details on why using waitqueue_active() without a preceding
barrier is unsafe, please see the comment before the waitqueue_active()
definition in include/linux/wait.h.

Add the missing memory barrier by switching to using wq_has_sleeper().

Fixes: 6f75723190 ("dm: remove the pending IO accounting")
Fixes: c4576aed8d ("dm: fix request-based dm's use of dm_wait_for_completion")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2019-02-06 17:24:37 -05:00
Yufen Yu
ebda52fa1b raid1: simplify raid1_error function
Remove redundance set_bit and let code simplify.

Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-02-04 10:37:11 -08:00
Gustavo A. R. Silva
f1e5b6239b md-linear: use struct_size() in kzalloc()
One of the more common cases of allocation size calculations is finding the
size of a structure that has a zero-sized array at the end, along with memory
for some number of elements for that array. For example:

struct foo {
    int stuff;
    void *entry[];
};

instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can now
use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-02-04 10:37:11 -08:00
Alexei Naberezhnov
483cbbeddd md/raid5: fix 'out of memory' during raid cache recovery
This fixes the case when md array assembly fails because of raid cache recovery
unable to allocate a stripe, despite attempts to replay stripes and increase
cache size. This happens because stripes released by r5c_recovery_replay_stripes
and raid5_set_cache_size don't become available for allocation immediately.
Released stripes first are placed on conf->released_stripes list and require
md thread to merge them on conf->inactive_list before they can be allocated.

Patch allows final allocation attempt during cache recovery to wait for
new stripes to become availabe for allocation.

Cc: linux-raid@vger.kernel.org
Cc: Shaohua Li <shli@kernel.org>
Cc: linux-stable <stable@vger.kernel.org> # 4.10+
Fixes: b4c625c673 ("md/r5cache: r5cache recovery: part 1")
Signed-off-by: Alexei Naberezhnov <anaberezhnov@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
2019-01-28 11:44:40 -08:00