ability to handle partial request completions -- otherwise with the
current SCSI LLDs these changes could lead to silent data corruption.
- Fix two DM version bumps that were missing from the initial 4.2 DM
pull request (enabled userspace lvm2 to know certain changes have been
made).
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Merge tag 'dm-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
"Apologies for not pressing this request-based DM partial completion
issue further, it was an oversight on my part. We'll have to get it
fixed up properly and revisit for a future release.
- Revert block and DM core changes the removed request-based DM's
ability to handle partial request completions -- otherwise with the
current SCSI LLDs these changes could lead to silent data
corruption.
- Fix two DM version bumps that were missing from the initial 4.2 DM
pull request (enabled userspace lvm2 to know certain changes have
been made)"
* tag 'dm-4.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm cache policy smq: fix "default" version to be 1.4.0
dm: bump the ioctl version to 4.32.0
Revert "block, dm: don't copy bios for request clones"
Revert "dm: do not allocate any mempools for blk-mq request-based DM"
Merge second patchbomb from Andrew Morton:
- most of the rest of MM
- lots of misc things
- procfs updates
- printk feature work
- updates to get_maintainer, MAINTAINERS, checkpatch
- lib/ updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (96 commits)
exit,stats: /* obey this comment */
coredump: add __printf attribute to cn_*printf functions
coredump: use from_kuid/kgid when formatting corename
fs/reiserfs: remove unneeded cast
NILFS2: support NFSv2 export
fs/befs/btree.c: remove unneeded initializations
fs/minix: remove unneeded cast
init/do_mounts.c: add create_dev() failure log
kasan: remove duplicate definition of the macro KASAN_FREE_PAGE
fs/efs: femove unneeded cast
checkpatch: emit "NOTE: <types>" message only once after multiple files
checkpatch: emit an error when there's a diff in a changelog
checkpatch: validate MODULE_LICENSE content
checkpatch: add multi-line handling for PREFER_ETHER_ADDR_COPY
checkpatch: suggest using eth_zero_addr() and eth_broadcast_addr()
checkpatch: fix processing of MEMSET issues
checkpatch: suggest using ether_addr_equal*()
checkpatch: avoid NOT_UNIFIED_DIFF errors on cover-letter.patch files
checkpatch: remove local from codespell path
checkpatch: add --showfile to allow input via pipe to show filenames
...
Commit bccab6a0 ("dm cache: switch the "default" cache replacement
policy from mq to smq") should've incremented the "default" policy's
version number to 1.4.0 rather than reverting to version 1.0.0.
Reported-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This reverts commit 5f1b670d0b.
Justification for revert as reported in this dm-devel post:
https://www.redhat.com/archives/dm-devel/2015-June/msg00160.html
this change should not be pushed to mainline yet.
Firstly, Christoph has a newer version of the patch that fixes silent
data corruption problem:
https://www.redhat.com/archives/dm-devel/2015-May/msg00229.html
And the new version still depends on LLDDs to always complete requests
to the end when error happens, while block API doesn't enforce such a
requirement. If the assumption is ever broken, the inconsistency between
request and bio (e.g. rq->__sector and rq->bio) will cause silent data
corruption:
https://www.redhat.com/archives/dm-devel/2015-June/msg00022.html
Reported-by: Junichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
There's no point in starting over when we meet a '/'. This also
eliminates a stack variable and a little .text.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- blk-mq request-based DM no longer uses any mempools now that partial
completions are no longer handled as part of cloned requests
- DM raid cleanups and support for MD raid0
- DM cache core advances and a new stochastic-multi-queue (smq) cache
replacement policy
- smq is the new default dm-cache policy
- DM thinp cleanups and much more efficient large discard support
- DM statistics support for request-based DM and nanosecond resolution
timestamps
- Fixes to DM stripe, DM log-writes, DM raid1 and DM crypt
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Merge tag 'dm-4.2-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- DM core cleanups:
* blk-mq request-based DM no longer uses any mempools now that
partial completions are no longer handled as part of cloned
requests
- DM raid cleanups and support for MD raid0
- DM cache core advances and a new stochastic-multi-queue (smq) cache
replacement policy
* smq is the new default dm-cache policy
- DM thinp cleanups and much more efficient large discard support
- DM statistics support for request-based DM and nanosecond resolution
timestamps
- Fixes to DM stripe, DM log-writes, DM raid1 and DM crypt
* tag 'dm-4.2-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (39 commits)
dm stats: add support for request-based DM devices
dm stats: collect and report histogram of IO latencies
dm stats: support precise timestamps
dm stats: fix divide by zero if 'number_of_areas' arg is zero
dm cache: switch the "default" cache replacement policy from mq to smq
dm space map metadata: fix occasional leak of a metadata block on resize
dm thin metadata: fix a race when entering fail mode
dm thin: fail messages with EOPNOTSUPP when pool cannot handle messages
dm thin: range discard support
dm thin metadata: add dm_thin_remove_range()
dm thin metadata: add dm_thin_find_mapped_range()
dm btree: add dm_btree_remove_leaves()
dm stats: Use kvfree() in dm_kvfree()
dm cache: age and write back cache entries even without active IO
dm cache: prefix all DMERR and DMINFO messages with cache device name
dm cache: add fail io mode and needs_check flag
dm cache: wake the worker thread every time we free a migration object
dm cache: add stochastic-multi-queue (smq) policy
dm cache: boost promotion of blocks that will be overwritten
dm cache: defer whole cells
...
Pull cgroup writeback support from Jens Axboe:
"This is the big pull request for adding cgroup writeback support.
This code has been in development for a long time, and it has been
simmering in for-next for a good chunk of this cycle too. This is one
of those problems that has been talked about for at least half a
decade, finally there's a solution and code to go with it.
Also see last weeks writeup on LWN:
http://lwn.net/Articles/648292/"
* 'for-4.2/writeback' of git://git.kernel.dk/linux-block: (85 commits)
writeback, blkio: add documentation for cgroup writeback support
vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
writeback: do foreign inode detection iff cgroup writeback is enabled
v9fs: fix error handling in v9fs_session_init()
bdi: fix wrong error return value in cgwb_create()
buffer: remove unusued 'ret' variable
writeback: disassociate inodes from dying bdi_writebacks
writeback: implement foreign cgroup inode bdi_writeback switching
writeback: add lockdep annotation to inode_to_wb()
writeback: use unlocked_inode_to_wb transaction in inode_congested()
writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
writeback: implement [locked_]inode_to_wb_and_lock_list()
writeback: implement foreign cgroup inode detection
writeback: make writeback_control track the inode being written back
writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
mm: vmscan: disable memcg direct reclaim stalling if cgroup writeback support is in use
writeback: implement memcg writeback domain based throttling
writeback: reset wb_domain->dirty_limit[_tstmp] when memcg domain size changes
writeback: implement memcg wb_domain
writeback: update wb_over_bg_thresh() to use wb_domain aware operations
...
Pull core block IO update from Jens Axboe:
"Nothing really major in here, mostly a collection of smaller
optimizations and cleanups, mixed with various fixes. In more detail,
this contains:
- Addition of policy specific data to blkcg for block cgroups. From
Arianna Avanzini.
- Various cleanups around command types from Christoph.
- Cleanup of the suspend block I/O path from Christoph.
- Plugging updates from Shaohua and Jeff Moyer, for blk-mq.
- Eliminating atomic inc/dec of both remaining IO count and reference
count in a bio. From me.
- Fixes for SG gap and chunk size support for data-less (discards)
IO, so we can merge these better. From me.
- Small restructuring of blk-mq shared tag support, freeing drivers
from iterating hardware queues. From Keith Busch.
- A few cfq-iosched tweaks, from Tahsin Erdogan and me. Makes the
IOPS mode the default for non-rotational storage"
* 'for-4.2/core' of git://git.kernel.dk/linux-block: (35 commits)
cfq-iosched: fix other locations where blkcg_to_cfqgd() can return NULL
cfq-iosched: fix sysfs oops when attempting to read unconfigured weights
cfq-iosched: move group scheduling functions under ifdef
cfq-iosched: fix the setting of IOPS mode on SSDs
blktrace: Add blktrace.c to BLOCK LAYER in MAINTAINERS file
block, cgroup: implement policy-specific per-blkcg data
block: Make CFQ default to IOPS mode on SSDs
block: add blk_set_queue_dying() to blkdev.h
blk-mq: Shared tag enhancements
block: don't honor chunk sizes for data-less IO
block: only honor SG gap prevention for merges that contain data
block: fix returnvar.cocci warnings
block, dm: don't copy bios for request clones
block: remove management of bi_remaining when restoring original bi_end_io
block: replace trylock with mutex_lock in blkdev_reread_part()
block: export blkdev_reread_part() and __blkdev_reread_part()
suspend: simplify block I/O handling
block: collapse bio bit space
block: remove unused BIO_RW_BLOCK and BIO_EOF flags
block: remove BIO_EOPNOTSUPP
...
This makes it possible to use dm stats with DM multipath.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add an option to dm statistics to collect and report a histogram of
IO latencies.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Make it possible to use precise timestamps with nanosecond granularity
in dm statistics.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If the number_of_areas argument was zero the kernel would crash on
div-by-zero. Add better input validation.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # v3.12+
The Stochastic multiqueue (SMQ) policy (vs MQ) offers the promise of
less memory utilization, improved performance and increased adaptability
in the face of changing workloads. SMQ also does not have any
cumbersome tuning knobs.
Users may switch from "mq" to "smq" simply by appropriately reloading a
DM table that is using the cache target. Doing so will cause all of the
mq policy's hints to be dropped. Also, performance of the cache may
degrade slightly until smq recalculates the origin device's hotspots
that should be cached.
In the future the "mq" policy will just silently make use of "smq" and
the mq code will be removed.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
The metadata space map has a simplified 'bootstrap' mode that is
operational when extending the space maps. Whilst in this mode it's
possible for some refcount decrement operations to become queued (eg, as
a result of shadowing one of the bitmap indexes). These decrements were
not being applied when switching out of bootstrap mode.
The effect of this bug was the leaking of a 4k metadata block. This is
detected by the latest version of thin_check as a non fatal error.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
MD_RECOVERY_DONE is normally cleared by md_check_recovery after a
resync etc finished. However it is possible for raid5_start_reshape
to race and start a reshape before MD_RECOVERY_DONE is cleared. This
can lean to multiple reshapes running at the same time, which isn't
good.
To make sure it is cleared before starting a reshape, and also clear
it when reaping a thread, just to be safe.
Signed-off-by: NeilBrown <neilb@suse.de>
Checking ->sync_thread without holding the mddev_lock()
isn't really safe, even after flushing the workqueue which
ensures md_start_sync() has been run.
While this code is waiting for the lock, md_check_recovery could reap
the thread itself, and then start another thread (e.g. recovery might
finish, then reshape starts). When this thread gets the lock
md_start_sync() hasn't run so it doesn't get reaped, but
MD_RECOVERY_RUNNING gets cleared. This allows two threads to start
which leads to confusion.
So don't both if MD_RECOVERY_RUNNING isn't set, but if it is do
the flush and the test and the reap all under the mddev_lock to
avoid any race with md_check_recovery.
Signed-off-by: NeilBrown <neilb@suse.de>
Fixes: 6791875e2e ("md: make reconfig_mutex optional for writes to md sysfs files.")
Cc: stable@vger.kernel.org (v4.0+)
Returning zero from a 'store' function is bad.
The return value should be either len length of the string
or an error.
So use 'len' if 'err' is zero.
Fixes: 6791875e2e ("md: make reconfig_mutex optional for writes to md sysfs files.")
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@vger.kernel (v4.0+)
In dm_thin_find_block() the ->fail_io flag was checked outside the
metadata device's root_lock, causing dm_thin_find_block() to race with
the setting of this flag.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use EOPNOTSUPP, rather than EINVAL, error code when user attempts to
send the pool a message. Otherwise usespace is led to believe the
message failed due to invalid argument.
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Previously REQ_DISCARD bios have been split into block sized chunks
before submission to the thin target. There are a couple of issues with
this:
- If the block size is small, a large discard request can
get broken up into a great many bios which is both slow and causes
a lot of memory pressure.
- The thin pool block size and the discard granularity for the
underlying data device need to be compatible if we want to passdown
the discard.
This patch relaxes the block size granularity for thin devices. It
makes use of the recent range locking added to the bio_prison to
quiesce a whole range of thin blocks before unmapping them. Once a
thin range has been unmapped the discard can then be passed down to
the data device for those sub ranges where the data blocks are no
longer used (ie. they weren't shared in the first place).
This patch also doesn't make any apologies about open-coding portions
of block core as a means to supporting async discard completions in the
near-term -- if/when late bio splitting lands it'll all get cleaned up.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Retrieve the next run of contiguously mapped blocks. Useful for working
out where to break up IO.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The policy tick() method is normally called from interrupt context.
Both the mq and smq policies do some bottom half work for the tick
method in their map functions. However if no IO is going through the
cache, then that bottom half work doesn't occur. With these policies
this means recently hit entries do not age and do not get written
back as early as we'd like.
Fix this by introducing a new 'can_block' parameter to the tick()
method. When this is set the bottom half work occurs immediately.
'can_block' is set when the tick method is called every second by the
core target (not in interrupt context).
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If a cache metadata operation fails (e.g. transaction commit) the
cache's metadata device will abort the current transaction, set a new
needs_check flag, and the cache will transition to "read-only" mode. If
aborting the transaction or setting the needs_check flag fails the cache
will transition to "fail-io" mode.
Once needs_check is set the cache device will not be allowed to
activate. Activation requires write access to metadata. Future work is
needed to add proper support for running the cache in read-only mode.
Once in fail-io mode the cache will report a status of "Fail".
Also, add commit() wrapper that will disallow commits if in read_only or
fail mode.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When the cache is idle, writeback work was only being issued every
second. With this change outstanding writebacks are streamed
constantly. This offers a writeback performance improvement.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The stochastic-multi-queue (smq) policy addresses some of the problems
with the current multiqueue (mq) policy.
Memory usage
------------
The mq policy uses a lot of memory; 88 bytes per cache block on a 64
bit machine.
SMQ uses 28bit indexes to implement it's data structures rather than
pointers. It avoids storing an explicit hit count for each block. It
has a 'hotspot' queue rather than a pre cache which uses a quarter of
the entries (each hotspot block covers a larger area than a single
cache block).
All these mean smq uses ~25bytes per cache block. Still a lot of
memory, but a substantial improvement nontheless.
Level balancing
---------------
MQ places entries in different levels of the multiqueue structures
based on their hit count (~ln(hit count)). This means the bottom
levels generally have the most entries, and the top ones have very
few. Having unbalanced levels like this reduces the efficacy of the
multiqueue.
SMQ does not maintain a hit count, instead it swaps hit entries with
the least recently used entry from the level above. The over all
ordering being a side effect of this stochastic process. With this
scheme we can decide how many entries occupy each multiqueue level,
resulting in better promotion/demotion decisions.
Adaptability
------------
The MQ policy maintains a hit count for each cache block. For a
different block to get promoted to the cache it's hit count has to
exceed the lowest currently in the cache. This means it can take a
long time for the cache to adapt between varying IO patterns.
Periodically degrading the hit counts could help with this, but I
haven't found a nice general solution.
SMQ doesn't maintain hit counts, so a lot of this problem just goes
away. In addition it tracks performance of the hotspot queue, which
is used to decide which blocks to promote. If the hotspot queue is
performing badly then it starts moving entries more quickly between
levels. This lets it adapt to new IO patterns very quickly.
Performance
-----------
In my tests SMQ shows substantially better performance than MQ. Once
this matures a bit more I'm sure it'll become the default policy.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.
This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it. c files
which need access to more backing-dev details now include
backing-dev.h directly. This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.
v2: fs/fat build failure fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback)
and the role of the separation is unclear. For cgroup support for
writeback IOs, a bdi will be updated to host multiple wb's where each
wb serves writeback IOs of a different cgroup on the bdi. To achieve
that, a wb should carry all states necessary for servicing writeback
IOs for a cgroup independently.
This patch moves bdi->state into wb.
* enum bdi_state is renamed to wb_state and the prefix of all enums is
changed from BDI_ to WB_.
* Explicit zeroing of bdi->state is removed without adding zeoring of
wb->state as the whole data structure is zeroed on init anyway.
* As there's still only one bdi_writeback per backing_dev_info, all
uses of bdi->state are mechanically replaced with bdi->wb.state
introducing no behavior changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: drbd-dev@lists.linbit.com
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
testing from Junichi Nomura and Bart Van Assche.
Also fix a casting bug in dm_merge_bvec() that could cause only a single
page to be added to a bio (Joe identified this while testing dm-cache
writeback).
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Merge tag 'dm-4.1-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device-mapper fixes from Mike Snitzer:
"Quite a few fixes for DM's blk-mq support thanks to extra DM multipath
testing from Junichi Nomura and Bart Van Assche.
Also fix a casting bug in dm_merge_bvec() that could cause only a
single page to be added to a bio (Joe identified this while testing
dm-cache writeback)"
* tag 'dm-4.1-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm: fix casting bug in dm_merge_bvec()
dm: fix reload failure of 0 path multipath mapping on blk-mq devices
dm: fix false warning in free_rq_clone() for unmapped requests
dm: requeue from blk-mq dm_mq_queue_rq() using BLK_MQ_RQ_QUEUE_BUSY
dm mpath: fix leak of dm_mpath_io structure in blk-mq .queue_rq error path
dm: fix NULL pointer when clone_and_map_rq returns !DM_MAPIO_REMAPPED
dm: run queue on re-queue
When considering whether to move a block to the cache we already give
preferential treatment to discarded blocks, since they are cheap to
promote (no read of the origin required since the data is junk).
The same is true of blocks that are about to be completely
overwritten, so we likewise boost their promotion chances.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Currently individual bios are deferred to the worker thread if they
cannot be processed immediately (eg, a block is in the process of
being moved to the fast device).
This patch passes whole cells across to the worker. This saves
reaquiring the cell, and also collects bios destined for the same block
together, which allows them to be mapped with a single look up to the
policy. This reduces the overhead of using dm-cache.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Rather than always releasing the prisoners in a cell, the client may
want to promote one of them to be the new holder. There is a race here
though between releasing an empty cell, and other threads adding new
inmates. So this function makes the decision with its lock held.
This function can have two outcomes:
i) An inmate is promoted to be the holder of the cell (return value of 0).
ii) The cell has no inmate for promotion and is released (return value of 1).
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
We only allow non critical writeback if the origin is idle. It is up
to the policy to decide what writeback work is critical.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
A little class that keeps track of the volume of io that is in flight,
and the length of time that a device has been idle for.
FIXME: rather than jiffes, may be best to use ktime_t (to support faster
devices).
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
There is a race between a policy deciding to replace a cache entry,
the core target writing back any dirty data from this block, and other
IO threads doing IO to the same block.
This sort of problem is avoided most of the time by the core target
grabbing a bio prison cell before making the request to the policy.
But for a demotion the core target doesn't know which block will be
demoted, so can't do this in advance.
Fix this demotion race by introducing a callback to the policy interface
that allows the policy to grab the cell on behalf of the core target.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
A crypto driver can process requests synchronously or asynchronously
and can use an internal driver queue to backlog requests.
Add some comments to clarify internal logic and completion return codes.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Currently if there is a leg failure, the bio will be put into the hold
list until userspace does a remove/replace on the leg. Doing so in a
cluster config (clvmd) is problematic because there may be a temporary
path failure that results in cluster raid1 remove/replace. Such
recovery takes a long time due to a full resync.
Update dm-raid1 to optionally ignore these failures so bios continue
being issued without interrupton. To enable this feature userspace
must pass "keep_log" when creating the dm-raid1 device.
Signed-off-by: Lidong Zhong <lzhong@suse.com>
Tested-by: Liuhua Wang <lwang@suse.com>
Acked-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
On 32-bit:
drivers/md/dm-log-writes.c: In function ‘log_super’:
drivers/md/dm-log-writes.c:323: warning: integer constant is too large for ‘long’ type
Add a ULL suffix to WRITE_LOG_MAGIC to fix this.
Also add a ULL suffix to WRITE_LOG_VERSION as it's stored in a __le64
field.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add dm-raid access to the MD RAID0 personality to enable single zone
striping.
The following changes enable that access:
- add type definition to raid_types array
- make bitmap creation conditonal in super_validate(), because
bitmaps are not allowed in raid0
- set rdev->sectors to the data image size in super_validate()
to allow the raid0 personality to calculate the MD array
size properly
- use mdddev(un)lock() functions instead of direct mutex_(un)lock()
(wrapped in here because it's a trivial change)
- enhance raid_status() to always report full sync for raid0
so that userspace checks for 100% sync will succeed and allow
for resize (and takeover/reshape once added in future paches)
- enhance raid_resume() to not load bitmap in case of raid0
- add merge function to avoid data corruption (seen with readahead)
that resulted from bio payloads that grew too large. This problem
did not occur with the other raid levels because it either did not
apply without striping (raid1) or was avoided via stripe caching.
- raise version to 1.7.0 because of the raid0 API change
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Reviewed-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
- ensure maximum device limit in superblock
- rename DMPF_* (print flags) to CTR_FLAG_* (constructor flags)
and their respective struct raid_set member
- use strcasecmp() in raid10_format_to_md_layout() as in the constructor
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Reviewed-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Remove comment above parse_raid_params() that claims
"devices_handle_discard_safely" is a table line argument when it is
actually is a module parameter.
Also, backfill dm-raid target version 1.6.0 documentation.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Reviewed-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Leverage the block manager's read_only flag instead of duplicating it;
access with new dm_bm_is_read_only() method.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The overwrite has only ever about optimizing away the need to zero a
block if the entire block was being overwritten. As such it is only
relevant when zeroing is enabled.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
