Add support for journal disk hot add/remove. Mostly trival checks in md
part. The raid5 part is a little tricky. For hot-remove, we can't wait
pending write as it's called from raid5d. The wait will cause deadlock.
We simplily fail the hot-remove. A hot-remove retry can success
eventually since if journal disk is faulty all pending write will be
failed and finish. For hot-add, since an array supporting journal but
without journal disk will be marked read-only, we are safe to hot add
journal without stopping IO (should be read IO, while journal only
handles write IO).
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
get_seconds() API is not y2038 safe on 32 bit systems and the API
is deprecated. Replace it with calls to ktime_get_real_seconds()
API instead. Change mddev structure types to time64_t accordingly.
32 bit signed timestamps will overflow in the year 2038.
Change the user interface mdu_array_info_s structure timestamps:
ctime and utime values used in ioctls GET_ARRAY_INFO and
SET_ARRAY_INFO to unsigned int. This will extend the field to last
until the year 2106.
The long term plan is to get rid of ctime and utime values in
this structure as this information can be read from the on-disk
meta data directly.
Clamp the tim64_t timestamps to positive values with a max of U32_MAX
when returning from GET_ARRAY_INFO ioctl to accommodate above changes
in the data type of timestamps to unsigned int.
v0.90 on disk meta data uses u32 for maintaining time stamps.
So this will also last until year 2106.
Assumption is that the usage of v0.90 will be deprecated by
year 2106.
Timestamp fields in the on disk meta data for v1.0 version already
use 64 bit data types. Remove the truncation of the bits while
writing to or reading from these from the disk.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NeilBrown <neilb@suse.com>
When CONFIG_LBDAF is not set, sector_t is only 32-bits wide, which
means we cannot have devices with more than 2TB, and the code that
is trying to handle compatibility support for large devices in
md version 0.90 is meaningless but also causes a compile-time warning:
drivers/md/md.c: In function 'super_90_load':
drivers/md/md.c:1029:19: warning: large integer implicitly truncated to unsigned type [-Woverflow]
drivers/md/md.c: In function 'super_90_rdev_size_change':
drivers/md/md.c:1323:17: warning: large integer implicitly truncated to unsigned type [-Woverflow]
This adds a check for CONFIG_LBDAF to avoid even getting into this
code path, and also adds an explicit cast to let the compiler know
it doesn't have to warn about the truncation.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NeilBrown <neilb@suse.com>
MD_CHANGE_CLEAN had been replaced with MD_CHANGE_PENDING after
commit 070dc6 ("md: resolve confusion of MD_CHANGE_CLEAN"),
so make the change accordingly.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reloading of superblock must be performed under reconfig_mutex. However,
this cannot be done with md_reload_sb because it would deadlock with
the message DLM lock. So, we defer it in md_check_recovery() which is
executed by mddev->thread.
This introduces a new flag, MD_RELOAD_SB, which if set, will reload the
superblock. And good_device_nr is also added to 'struct mddev' which is
used to get the num of the good device within cluster raid.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
For clustered raid, we need to do extra actions when change
bitmap to none.
1. check if all the bitmap lock could be get or not, if yes then
we can continue the change since cluster raid is only active
in current node. Otherwise return fail and unlock the related
bitmap locks
2. set nodes to 0 and then leave cluster environment.
3. release other nodes's bitmap lock.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
If a spare device was marked faulty, it would not be reflected
in receiving nodes because it would mark it as activated and continue.
Continue the operation, so it may be set as faulty.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
The remove disk message does not need metadata_update_start(), but
can be an independent message.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
For cluster raid, if one disk couldn't be reach in one node, then
other nodes would receive the REMOVE message for the disk.
In receiving node, we can't call md_kick_rdev_from_array to remove
the disk from array synchronously since the disk might still be busy
in this node. So let's set a ClusterRemove flag on the disk, then
let the thread to do the removal job eventually.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
md currently doesn't allow a 'sync_action' such as 'reshape' to be set
while MD_RECOVERY_NEEDED is set.
This s a problem, particularly since commit 738a273806 as that can
cause ->check_shape to call mddev_resume() which sets
MD_RECOVERY_NEEDED. So by the time we come to start 'reshape' it is
very likely that MD_RECOVERY_NEEDED is still set.
Testing for this flag is not really needed and is in any case very
racy as it can be set at any moment - asynchronously. Any race
between setting a sync_action and setting MD_RECOVERY_NEEDED must
already be handled properly in some locked code, probably
md_check_recovery(), so remove the test here.
The test on MD_RECOVERY_RUNNING is also racy in the 'reshape' case
so we should test it again after getting mddev_lock().
As this fixes a race and a regression which can cause 'reshape' to
fail, it is suitable for -stable kernels since 4.1
Reported-by: Xiao Ni <xni@redhat.com>
Fixes: 738a273806 ("md/raid5: fix allocation of 'scribble' array.")
Cc: stable@vger.kernel.org (v4.1+)
Signed-off-by: NeilBrown <neilb@suse.com>
Commit 2910ff17d1
introduced a regression which would remove a recently added spare via
slot_store. Revert part of the patch which touches slot_store() and add
the disk directly using pers->hot_add_disk()
Fixes: 2910ff17d1 ("md: remove_and_add_spares() to activate specific
rdev")
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Neil pointed out setting journal disk role to raid_disks will confuse
reshape if we support reshape eventually. Switching the role to 0 (we
should be fine as long as the value >=0) and skip sysfs file creation to
avoid error.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.
Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Two major components to this update.
1/ the clustered-raid1 support from SUSE is nearly
complete. There are a few outstanding issues being
worked on. Maybe half a dozen patches will bring
this to a usable state.
2/ The first stage of journalled-raid5 support from
Facebook makes an appearance. With a journal
device configured (typically NVRAM or SSD), the
"RAID5 write hole" should be closed - a crash
during degraded operations cannot result in data
corruption.
The next stage will be to use the journal as a
write-behind cache so that latency can be reduced
and in some cases throughput increased by
performing more full-stripe writes.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=TD5o
-----END PGP SIGNATURE-----
Merge tag 'md/4.4' of git://neil.brown.name/md
Pull md updates from Neil Brown:
"Two major components to this update.
1) The clustered-raid1 support from SUSE is nearly complete. There
are a few outstanding issues being worked on. Maybe half a dozen
patches will bring this to a usable state.
2) The first stage of journalled-raid5 support from Facebook makes an
appearance. With a journal device configured (typically NVRAM or
SSD), the "RAID5 write hole" should be closed - a crash during
degraded operations cannot result in data corruption.
The next stage will be to use the journal as a write-behind cache
so that latency can be reduced and in some cases throughput
increased by performing more full-stripe writes.
* tag 'md/4.4' of git://neil.brown.name/md: (66 commits)
MD: when RAID journal is missing/faulty, block RESTART_ARRAY_RW
MD: set journal disk ->raid_disk
MD: kick out journal disk if it's not fresh
raid5-cache: start raid5 readonly if journal is missing
MD: add new bit to indicate raid array with journal
raid5-cache: IO error handling
raid5: journal disk can't be removed
raid5-cache: add trim support for log
MD: fix info output for journal disk
raid5-cache: use bio chaining
raid5-cache: small log->seq cleanup
raid5-cache: new helper: r5_reserve_log_entry
raid5-cache: inline r5l_alloc_io_unit into r5l_new_meta
raid5-cache: take rdev->data_offset into account early on
raid5-cache: refactor bio allocation
raid5-cache: clean up r5l_get_meta
raid5-cache: simplify state machine when caches flushes are not needed
raid5-cache: factor out a helper to run all stripes for an I/O unit
raid5-cache: rename flushed_ios to finished_ios
raid5-cache: free I/O units earlier
...
Pull block integrity updates from Jens Axboe:
""This is the joint work of Dan and Martin, cleaning up and improving
the support for block data integrity"
* 'for-4.4/integrity' of git://git.kernel.dk/linux-block:
block, libnvdimm, nvme: provide a built-in blk_integrity nop profile
block: blk_flush_integrity() for bio-based drivers
block: move blk_integrity to request_queue
block: generic request_queue reference counting
nvme: suspend i/o during runtime blk_integrity_unregister
md: suspend i/o during runtime blk_integrity_unregister
md, dm, scsi, nvme, libnvdimm: drop blk_integrity_unregister() at shutdown
block: Inline blk_integrity in struct gendisk
block: Export integrity data interval size in sysfs
block: Reduce the size of struct blk_integrity
block: Consolidate static integrity profile properties
block: Move integrity kobject to struct gendisk
When RAID-4/5/6 array suffers from missing journal device, we put
the array in read only state. We should not allow trasition to
read-write states (clean and active) before replacing journal device.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Set journal disk ->raid_disk to >=0, I choose raid_disks + 1 instead of
0, because we already have a disk with ->raid_disk 0 and this causes
sysfs entry creation conflict. A lot of places assumes disk with
->raid_disk >=0 is normal raid disk, so we add check for journal disk.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
When journal disk is faulty and we are reassemabling the raid array, the
journal disk is old. We don't allow the journal disk added to the raid
array. Since journal disk is missing in the array, the raid5 will mark
the array readonly.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
If a raid array has journal feature bit set, add a new bit to indicate
this. If the array is started without journal disk existing, we know
there is something wrong.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
journal disk can be faulty. The Journal and Faulty aren't exclusive with
each other.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
match_mddev_units is used to check whether 2 RAID arrays share
same disk(s). Arrays that share disk(s) will not do resync at the
same time for better performance (fewer HDD seek). However, this
check should not apply to Spare, Faulty, and Journal disks, as
they do not paticipate in resync.
In this patch, match_mddev_units skips check for disks with flag
"Faulty" or "Journal" or raid_disk < 0.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
If a raid array has journal, the journal can guarantee the consistency,
we can skip resync after a unclean shutdown. The exception is raid
creation or user initiated resync, which we still do a raid resync.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
This reverts commit 7eb418851f.
This commit is poorly justified, I can find not discusison in email,
and it clearly causes a problem.
If a device which is being recovered fails and is subsequently
re-added to an array, there could easily have been changes to the
array *before* the point where the recovery was up to. So the
recovery must start again from the beginning.
If a spare is being recovered and fails, then when it is re-added we
really should do a bitmap-based recovery up to the recovery-offset,
and then a full recovery from there. Before this reversion, we only
did the "full recovery from there" which is not corect. After this
reversion with will do a full recovery from the start, which is safer
but not ideal.
It will be left to a future patch to arrange the two different styles
of recovery.
Reported-and-tested-by: Nate Dailey <nate.dailey@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Cc: stable@vger.kernel.org (3.14+)
Fixes: 7eb418851f ("md: allow a partially recovered device to be hot-added to an array.")
Journal device stores data in a log structure. We need record the log
start. Here we override md superblock recovery_offset for this purpose.
This field of a journal device is meaningless otherwise.
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Next patches will use a disk as raid5/6 journaling. We need a new disk
role to present the journal device and add MD_FEATURE_JOURNAL to
feature_map for backward compability.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Add the following two macros for special roles: spare and faulty
MD_DISK_ROLE_SPARE 0xffff
MD_DISK_ROLE_FAULTY 0xfffe
Add MD_DISK_ROLE_MAX 0xff00 as the maximal possible regular role,
and minimal value of special role.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
To incorporate --grow feature executed on one node, other nodes need to
acknowledge the change in number of disks. Call update_raid_disks()
to update internal data structures.
This leads to call check_reshape() -> md_allow_write() -> md_update_sb(),
this results in a deadlock. This is done so it can safely allocate memory
(which might trigger writeback which might write to raid1). This is
not required for md with a bitmap.
In the clustered case, we don't perform md_update_sb() in md_allow_write(),
but in do_md_run(). Also we disable safemode for clustered mode.
mddev->recovery_cp need not be set in check_sb_changes() because this
is required only when a node reads another node's bitmap. mddev->recovery_cp
(which is read from sb->resync_offset), is set only if mddev is in_sync.
Since we disabled safemode, in_sync is set to zero.
In a clustered environment, the MD may not be in sync because another
node could be writing to it. So make sure that in_sync is not set in
case of clustered node in __md_stop_writes().
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Synchronize pending i/o against a change in the integrity profile to
avoid the possibility of spurious integrity errors. Given linear_add()
is suspending the mddev before manipulating the mddev, do the same for
the other personalities.
Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Now that the integrity profile is statically allocated there is no work
to do when shutting down an integrity enabled block device.
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: James Bottomley <JBottomley@Odin.com>
Acked-by: NeilBrown <neilb@suse.com>
Acked-by: Keith Busch <keith.busch@intel.com>
Acked-by: Vishal Verma <vishal.l.verma@intel.com>
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Up until now the_integrity profile has been dynamically allocated and
attached to struct gendisk after the disk has been made active.
This causes problems because NVMe devices need to register the profile
prior to the partition table being read due to a mandatory metadata
buffer requirement. In addition, DM goes through hoops to deal with
preallocating, but not initializing integrity profiles.
Since the integrity profile is small (4 bytes + a pointer), Christoph
suggested moving it to struct gendisk proper. This requires several
changes:
- Moving the blk_integrity definition to genhd.h.
- Inlining blk_integrity in struct gendisk.
- Removing the dynamic allocation code.
- Adding helper functions which allow gendisk to set up and tear down
the integrity sysfs dir when a disk is added/deleted.
- Adding a blk_integrity_revalidate() callback for updating the stable
pages bdi setting.
- The calls that depend on whether a device has an integrity profile or
not now key off of the bi->profile pointer.
- Simplifying the integrity support routines in DM (Mike Snitzer).
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
For cluster raid, we should not kick it from array if the disk can't be
remove from array successfully.
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Adding the disk worked incorrectly with the new reload code. Fix it:
- No operation should be performed on rdev marked as Candidate
- After a metadata update operation, kick disk if role is 0xfffe
else clear Candidate bit and continue with the regular change check.
- Saving the mode of the lock resource to check if token lock is already
locked, because it can be called twice while adding a disk. However,
unlock_comm() must be called only once.
- add_new_disk() is called by the node initiating the --add operation.
If it needs to be canceled, call add_new_disk_cancel(). The operation
is completed by md_update_sb() which will write and unlock the
communication.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Resync or recovery must be performed by only one node at a time.
A DLM lock resource, resync_lockres provides the mutual exclusion
so that only one node performs the recovery/resync at a time.
If a node is unable to get the resync_lockres, because recovery is
being performed by another node, it set MD_RECOVER_NEEDED so as
to schedule recovery in the future.
Remove the debug message in resync_info_update()
used during development.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
In a clustered environment, a change such as marking a device faulty,
can be recorded by any of the nodes. This is communicated to all the
nodes and re-recording such a change is unnecessary, and quite often
pretty disruptive.
With this patch, just before the update, we detect for the changes
and if the changes are already in superblock, we abort the update
after clearing all the flags
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
md_reload_sb is too simplistic and it explicitly needs to determine
the changes made by the writing node. However, there are multiple areas
where a simple reload could fail.
Instead, read the superblock of one of the "good" rdevs and update
the necessary information:
- read the superblock into a newly allocated page, by temporarily
swapping out rdev->sb_page and calling ->load_super.
- if that fails return
- if it succeeds, call check_sb_changes
1. iterates over list of active devices and checks the matching
dev_roles[] value.
If that is 'faulty', the device must be marked as faulty
- call md_error to mark the device as faulty. Make sure
not to set CHANGE_DEVS and wakeup mddev->thread or else
it would initiate a resync process, which is the responsibility
of the "primary" node.
- clear the Blocked bit
- Call remove_and_add_spares() to hot remove the device.
If the device is 'spare':
- call remove_and_add_spares() to get the number of spares
added in this operation.
- Reduce mddev->degraded to mark the array as not degraded.
2. reset recovery_cp
- read the rest of the rdevs to update recovery_offset. If recovery_offset
is equal to MaxSector, call spare_active() to set it In_sync
This required that recovery_offset be initialized to MaxSector, as
opposed to zero so as to communicate the end of sync for a rdev.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
remove_and_add_spares() checks for all devices to activate spare.
Change it to activate a specific device if a non-null rdev
argument is passed.
remove_and_add_spares() can be used to activate spares in
slot_store() as well.
For hot_remove_disk(), check if rdev->raid_disk == -1 before
calling remove_and_add_spares()
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Suspending the entire device for resync could take too long. Resync
in small chunks.
cluster's resync window (32M) is maintained in r1conf as
cluster_sync_low and cluster_sync_high and processed in
raid1's sync_request(). If the current resync is outside the cluster
resync window:
1. Set the cluster_sync_low to curr_resync_completed.
2. Check if the sync will fit in the new window, if not issue a
wait_barrier() and set cluster_sync_low to sector_nr.
3. Set cluster_sync_high to cluster_sync_low + resync_window.
4. Send a message to all nodes so they may add it in their suspension
list.
bitmap_cond_end_sync is modified to allow to force a sync inorder
to get the curr_resync_completed uptodate with the sector passed.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Add BITMAP_MAJOR_CLUSTERED as 5, in order to prevent older kernels
to assemble a clustered device.
In order to maximize compatibility, the major version is set to
BITMAP_MAJOR_CLUSTERED *only* if the bitmap is clustered.
Added MD_FEATURE_CLUSTERED in order to return error for older
kernels which would assemble MD even if the bitmap is corrupted.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
If faulty disks of an array are more than allowed degraded number, the
array enters error handling. It will be marked as read-only with
MD_CHANGE_PENDING/RECOVERY_NEEDED set. But currently recovery doesn't
clear CHANGE_PENDING bit for read-only array. If MD_CHANGE_PENDING is
set for a raid5 array, all returned IO will be hold on a list till the
bit is clear. But recovery nevery clears this bit, the IO is always in
pending state and nevery finish. This has bad effects like upper layer
can't get an IO error and the array can't be stopped.
Fixes: c3cce6cda1 ("md/raid5: ensure device failure recorded before write request returns.")
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
If a superblock update is pending, wait for it to complete before
letting md_set_readonly() switch to readonly.
Otherwise we might lose important information about a device having
failed.
For external arrays, waiting for superblock updates can wait on
user-space, so in that case, just return an error.
Reported-and-tested-by: Shaohua Li <shli@fb.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Pull core block updates from Jens Axboe:
"This first core part of the block IO changes contains:
- Cleanup of the bio IO error signaling from Christoph. We used to
rely on the uptodate bit and passing around of an error, now we
store the error in the bio itself.
- Improvement of the above from myself, by shrinking the bio size
down again to fit in two cachelines on x86-64.
- Revert of the max_hw_sectors cap removal from a revision again,
from Jeff Moyer. This caused performance regressions in various
tests. Reinstate the limit, bump it to a more reasonable size
instead.
- Make /sys/block/<dev>/queue/discard_max_bytes writeable, by me.
Most devices have huge trim limits, which can cause nasty latencies
when deleting files. Enable the admin to configure the size down.
We will look into having a more sane default instead of UINT_MAX
sectors.
- Improvement of the SGP gaps logic from Keith Busch.
- Enable the block core to handle arbitrarily sized bios, which
enables a nice simplification of bio_add_page() (which is an IO hot
path). From Kent.
- Improvements to the partition io stats accounting, making it
faster. From Ming Lei.
- Also from Ming Lei, a basic fixup for overflow of the sysfs pending
file in blk-mq, as well as a fix for a blk-mq timeout race
condition.
- Ming Lin has been carrying Kents above mentioned patches forward
for a while, and testing them. Ming also did a few fixes around
that.
- Sasha Levin found and fixed a use-after-free problem introduced by
the bio->bi_error changes from Christoph.
- Small blk cgroup cleanup from Viresh Kumar"
* 'for-4.3/core' of git://git.kernel.dk/linux-block: (26 commits)
blk: Fix bio_io_vec index when checking bvec gaps
block: Replace SG_GAPS with new queue limits mask
block: bump BLK_DEF_MAX_SECTORS to 2560
Revert "block: remove artifical max_hw_sectors cap"
blk-mq: fix race between timeout and freeing request
blk-mq: fix buffer overflow when reading sysfs file of 'pending'
Documentation: update notes in biovecs about arbitrarily sized bios
block: remove bio_get_nr_vecs()
fs: use helper bio_add_page() instead of open coding on bi_io_vec
block: kill merge_bvec_fn() completely
md/raid5: get rid of bio_fits_rdev()
md/raid5: split bio for chunk_aligned_read
block: remove split code in blkdev_issue_{discard,write_same}
btrfs: remove bio splitting and merge_bvec_fn() calls
bcache: remove driver private bio splitting code
block: simplify bio_add_page()
block: make generic_make_request handle arbitrarily sized bios
blk-cgroup: Drop unlikely before IS_ERR(_OR_NULL)
block: don't access bio->bi_error after bio_put()
block: shrink struct bio down to 2 cache lines again
...
When a write to one of the legs of a RAID1 fails, the failure is
recorded in the metadata of the other leg(s) so that after a restart
the data on the failed drive wont be trusted even if that drive seems
to be working again (maybe a cable was unplugged).
Similarly when we record a bad-block in response to a write failure,
we must not let the write complete until the bad-block update is safe.
Currently there is no interlock between the write request completing
and the metadata update. So it is possible that the write will
complete, the app will confirm success in some way, and then the
machine will crash before the metadata update completes.
This is an extremely small hole for a racy to fit in, but it is
theoretically possible and so should be closed.
So:
- set MD_CHANGE_PENDING when requesting a metadata update for a
failed device, so we can know with certainty when it completes
- queue requests that experienced an error on a new queue which
is only processed after the metadata update completes
- call raid_end_bio_io() on bios in that queue when the time comes.
Signed-off-by: NeilBrown <neilb@suse.com>
This code looks racy.
The only possible race is if two modules try to register at the same
time and that won't happen. But make the code look safe anyway.
Signed-off-by: NeilBrown <neilb@suse.com>
When node A stops an array while the array is doing a resync, we need
to let another node B take over the resync task.
To achieve the goal, we need the A send an explicit BITMAP_NEEDS_SYNC
message to the cluster. And the node B which received that message will
invoke __recover_slot to do resync.
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
We used to set up the safemode_timer timer in md_run. If md_run
would fail before the timer was set up we'd end up trying to modify
a timer that doesn't have a callback function when we access safe_delay_store,
which would trigger a BUG.
neilb: delete init_timer() call as setup_timer() does that.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: NeilBrown <neilb@suse.com>
There can be a small window between the moment that recovery
actually writes the last block and the time when various sysfs
and /proc/mdstat attributes report that it has finished.
During this time, 'sync_completed' can have the wrong value.
This can confuse monitoring software.
So:
- don't set curr_resync_completed beyond the end of the devices,
- set it correctly when resync/recovery has completed.
Signed-off-by: NeilBrown <neilb@suse.com>