Update my email address to kernel.org to allow distinction between my
"upstream" and "Red" Hats.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Optimizes dm_io_dec_pending() slightly by avoiding local variables.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Remove the from_wq argument from dm_sumbit_bio_remap(). Eliminates the
need for dm_sumbit_bio_remap() callers to know whether they are
calling for a workqueue or from the original dm_submit_bio().

Add map_task to dm_io struct, record the map_task in alloc_io and
clear it after all target ->map() calls have completed. Update
dm_sumbit_bio_remap to check if 'current' matches io->map_task rather
than rely on passed 'from_rq' argument.

This change really simplifies the chore of porting each DM target to
using dm_sumbit_bio_remap() because there is no longer the risk of
programming error by not completely knowing all the different contexts
a particular method that calls dm_sumbit_bio_remap() might be used in.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

If a target uses dm_submit_bio_remap() it should set
ti->accounts_remapped_io.

Also, switch dm_start_io_acct() WARN_ON to WARN_ON_ONCE.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Support bio polling (REQ_POLLED) in the following approach:

1) only support io polling on normal READ/WRITE, and other abnormal IOs
still fallback to IRQ mode, so the target io (and DM's clone bio) is
exactly inside the dm io.

2) hold one refcnt on io->io_count after submitting this dm bio with
REQ_POLLED

3) support dm native bio splitting, any dm io instance associated with
current bio will be added into one list which head is bio->bi_private
which will be recovered before ending this bio

4) implement .poll_bio() callback, call bio_poll() on the single target
bio inside the dm io which is retrieved via bio->bi_bio_drv_data; call
dm_io_dec_pending() after the target io is done in .poll_bio()

5) enable QUEUE_FLAG_POLL if all underlying queues enable QUEUE_FLAG_POLL,
which is based on Jeffle's previous patch.

These changes are good for a 30-35% IOPS improvement for polled IO.

For detailed test results please see (Jens, thanks for testing!):
https://listman.redhat.com/archives/dm-devel/2022-March/049868.html
or https://marc.info/?l=linux-block&m=164684246214700&w=2Tested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Prepare for supporting IO polling for bio-based driver.

Add ->poll_bio callback so that bio-based driver can provide their own
logic for polling bio.

Also fix ->submit_bio_bio typo in comment block above
__submit_bio_noacct.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Just use the %pg format specifier instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Just use the %pg format specifier to print the block device name
directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Also remove empty newline before 'out:' label at end of __bind.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Update both bio-based and request-based DM to requeue IO if the
mapping table not available.

This race of IO being submitted before the DM device ready is so
narrow, yet possible for initial table load given that the DM device's
request_queue is created prior, that it best to requeue IO to handle
this unlikely case.
Reported-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Commit 7eaceacc ("block: remove per-queue plugging") dropped
unplug_delay and blk_unplug(). Plus, the current kernel has no
fundamental difference between sync_io() and async_io() except
sync_io() uses sync_io_complete() as the notify.fn and explicitly
calls wait_for_completion_io() to sync. The comment isn't valid
any more.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Use time_is_before_jiffies() to improve code readability.
Signed-off-by: Wang Qing <wangqing@vivo.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Explicitly convert unsigned int in the right of the conditional
expression to int to match the left side operand and the return type,
fixing the following compiler warning:

drivers/md/dm-crypt.c:2593:43: warning: signed and unsigned
type in conditional expression [-Wsign-compare]

Fixes: c538f6ec ("dm crypt: add ability to use keys from the kernel key retention service")
Signed-off-by: Aashish Sharma <shraash@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm_cleanup_zoned_dev() uses queue, so it must be called
before blk_cleanup_disk() starts its killing:

blk_cleanup_disk->blk_cleanup_queue()->kobject_put()->blk_release_queue()->
->...RCU...->blk_free_queue_rcu()->kmem_cache_free()

Otherwise, RCU callback may be executed first and
dm_cleanup_zoned_dev() will touch free'd memory:

 BUG: KASAN: use-after-free in dm_cleanup_zoned_dev+0x33/0xd0
 Read of size 8 at addr ffff88805ac6e430 by task dmsetup/681

 CPU: 4 PID: 681 Comm: dmsetup Not tainted 5.17.0-rc2+ #6
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x57/0x7d
  print_address_description.constprop.0+0x1f/0x150
  ? dm_cleanup_zoned_dev+0x33/0xd0
  kasan_report.cold+0x7f/0x11b
  ? dm_cleanup_zoned_dev+0x33/0xd0
  dm_cleanup_zoned_dev+0x33/0xd0
  __dm_destroy+0x26a/0x400
  ? dm_blk_ioctl+0x230/0x230
  ? up_write+0xd8/0x270
  dev_remove+0x156/0x1d0
  ctl_ioctl+0x269/0x530
  ? table_clear+0x140/0x140
  ? lock_release+0xb2/0x750
  ? remove_all+0x40/0x40
  ? rcu_read_lock_sched_held+0x12/0x70
  ? lock_downgrade+0x3c0/0x3c0
  ? rcu_read_lock_sched_held+0x12/0x70
  dm_ctl_ioctl+0xa/0x10
  __x64_sys_ioctl+0xb9/0xf0
  do_syscall_64+0x3b/0x90
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7fb6dfa95c27

Fixes: bb37d772 ("dm: introduce zone append emulation")
Cc: stable@vger.kernel.org
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

It appears like cmd could be a Spectre v1 gadget as it's supplied by a
user and used as an array index. Prevent the contents of kernel memory
from being leaked to userspace via speculative execution by using
array_index_nospec.
Signed-off-by: Jordy Zomer <jordy@pwning.systems>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Remove the second 'a'.
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

All entries measured by dm ima are prefixed by a version string
(dm_version=N.N.N). When there is no data to measure, the entire buffer is
overwritten with a string containing the version string again and the
length of that string is added to the length of the version string.
The new length is now wrong because it contains the version string twice.

This caused entries like this:
dm_version=4.45.0;name=test,uuid=test;table_clear=no_data; \
\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00 \
current_device_capacity=204808;
Signed-off-by: Thore Sommer <public@thson.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

The 'table' static array is read-only so it make sense to make
it const. Add in the int type to clean up checkpatch warning.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Care was taken to support kcryptd_io_read being called from crypt_map
or workqueue.  Use of an intermediate CRYPT_MAP_READ_GFP gfp_t
(defined as GFP_NOWAIT) should protect from maintenance burden if that
flag were to change for some reason.
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Where possible, switch from early bio-based IO accounting (at the time
DM clones each incoming bio) to late IO accounting just before each
remapped bio is issued to underlying device via submit_bio_noacct().

Allows more precise bio-based IO accounting for DM targets that use
their own workqueues to perform additional processing of each bio in
conjunction with their DM_MAPIO_SUBMITTED return from their map
function. When a target is updated to use dm_submit_bio_remap() they
must also set ti->accounts_remapped_io to true.

Use xchg() in start_io_acct(), as suggested by Mikulas, to ensure each
IO is only started once.  The xchg race only happens if
__send_duplicate_bios() sends multiple bios -- that case is reflected
via tio->is_duplicate_bio.  Given the niche nature of this race, it is
best to avoid any xchg performance penalty for normal IO.

For IO that was never submitted with dm_bio_submit_remap(), but the
target completes the clone with bio_endio, accounting is started then
ended and pending_io counter decremented.
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Formally disallow dm_accept_partial_bio() on clones created by
__send_duplicate_bios() because their len_ptr points to a shared
unsigned int.  __send_duplicate_bios() is only used for flush bios
and other "abnormal" bios (discards, writezeroes, etc). And
dm_accept_partial_bio() already didn't support flush bios.

Also refactor __send_changing_extent_only() to reflect it cannot fail.
As such __send_changing_extent_only() can update the clone_info before
__send_duplicate_bios() is called to fan-out __map_bio() calls.
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Remove one 4 byte hole in dm_io struct.
Remove two 4 byte holes in dm_target_io struct.
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Prep for being able to defer trace_block_bio_remap() until when the
bio is remapped and submitted by the DM target.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Commit 8615cb65 ("dm: remove useless loop in
__split_and_process_bio") showcased that we no longer loop.

Remove the bio_advance() in __split_and_process_bio() that was only
needed when looping was possible.

Similarly there is no need to advance the bio, using ci->sector
cursor, in __send_duplicate_bios().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

The flush_bio in question was just initialized to be empty, so there
is no way bio_has_data() will return true.  So remove stale BUG_ON().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Error path code (for handling DM_MAPIO_REQUEUE and DM_MAPIO_KILL) is
effectively identical.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Remove needless branching and indentation. Leaves code to catch
malformed op_is_zone_mgmt bios (they shouldn't have a payload).
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Fold __clone_and_map_data_bio into its only caller.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Rename __split_and_process_bio to dm_split_and_process_bio.
Rename __split_and_process_non_flush to __split_and_process_bio.

Also fix a stale comment and whitespace.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

Improves alignment and groups related members relative to cachelines.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

There is no need for dm_io_dec_pending() to copy dm_io fields
anymore now that DM provides its own pending_io counters again.

The race documented in commit d208b894 ("dm: fix mempool NULL
pointer race when completing IO") no longer exists now that block
core's in_flight counters aren't used to signal all dm_io is
complete.

Also, rename {start,end}_io_acct to dm_{start,end}_io_acct.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm_stats_account_io()'s STAT_PRECISE_TIMESTAMPS support doesn't handle
the fact that with commit b879f915 ("dm: properly fix redundant
bio-based IO accounting") io->start_time _may_ be in the past (meaning
the start_io_acct() was deferred until later).

Add a new dm_stats_recalc_precise_timestamps() helper that will
set/clear a new 'precise_timestamps' flag in the dm_stats struct based
on whether any configured stats enable STAT_PRECISE_TIMESTAMPS.
And update DM core's alloc_io() to use dm_stats_record_start() to set
stats_aux.duration_ns if stats->precise_timestamps is true.

Also, remove unused 'last_sector' and 'last_rw' members from the
dm_stats struct.

Fixes: b879f915 ("dm: properly fix redundant bio-based IO accounting")
Cc: stable@vger.kernel.org
Co-developed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>