When a write error is detected, don't mark the device as failed
immediately but rather record the fact for handle_stripe to deal with.
Handle_stripe then attempts to record a bad block. Only if that fails
does the device get marked as faulty.
Signed-off-by: NeilBrown <neilb@suse.de>
If we get an uncorrectable read error - record a bad block rather than
failing the device.
And if these errors (which may be due to known bad blocks) cause
recovery to be impossible, record a bad block on the recovering
devices, or abort the recovery.
As we might abort a recovery without failing a device we need to teach
RAID5 about recovery_disabled handling.
Signed-off-by: NeilBrown <neilb@suse.de>
There are two times that we might read in raid5:
1/ when a read request fits within a chunk on a single
working device.
In this case, if there is any bad block in the range of
the read, we simply fail the cache-bypass read and
perform the read though the stripe cache.
2/ when reading into the stripe cache. In this case we
mark as failed any device which has a bad block in that
strip (1 page wide).
Note that we will both avoid reading and avoid writing.
This is correct (as we will never read from the block, there
is no point writing), but not optimal (as writing could 'fix'
the error) - that will be addressed later.
If we have not seen any write errors on the device yet, we treat a bad
block like a recent read error. This will encourage an attempt to fix
the read error which will either generate a write error, or will
ensure good data is stored there. We don't yet forget the bad block
in that case. That comes later.
Now that we honour bad blocks when reading we can allow devices with
bad blocks into the array.
Signed-off-by: NeilBrown <neilb@suse.de>
raid1d is too big with several deep branches.
So separate them out into their own functions.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
If we cannot read a block from anywhere during recovery, there is
now a better approach than just giving up.
We can record a bad block on each device and keep going - being
careful not to clear the bad block when a write succeeds as it might -
it will be a write of incorrect data.
We have now reached the state where - for raid1 - we only call
md_error if md_set_badblocks has failed.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
If we find a bad block while writing as part of resync/recovery we
need to report that back to raid1d which must record the bad block,
or fail the device.
Similarly when fixing a read error, a further error should just
record a bad block if possible rather than failing the device.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
When we get a write error (in the data area, not in metadata),
update the badblock log rather than failing the whole device.
As the write may well be many blocks, we trying writing each
block individually and only log the ones which fail.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
When performing write-behind we allocate pages to store the data
during write.
Previously we just keep a list of pages. Now we keep a list of
bi_vec which includes offset and size.
This means that the r1bio has complete information to create a new
bio which will be needed for retrying after write errors.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
If we succeed in writing to a block that was recorded as
being bad, we clear the bad-block record.
This requires some delayed handling as the bad-block-list update has
to happen in process-context.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
If we have seen any write error on a drive, then don't write to
any known-bad blocks on that drive.
If necessary, we divide the write request up into pieces just
like we do for reads, so each piece is either all written or
all not written to any given drive.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
It is only safe to choose not to write to a bad block if that bad
block is safely recorded in metadata - i.e. if it has been
'acknowledged'.
If it hasn't we need to wait for the acknowledgement.
We support that using rdev->blocked wait and
md_wait_for_blocked_rdev by introducing a new device flag
'BlockedBadBlock'.
This flag is only advisory.
It is cleared whenever we acknowledge a bad block, so that a waiter
can re-check the particular bad blocks that it is interested it.
It should be set by a caller when they find they need to wait.
This (set after test) is inherently racy, but as
md_wait_for_blocked_rdev already has a timeout, losing the race will
have minimal impact.
When we clear "Blocked" was also clear "BlockedBadBlocks" incase it
was set incorrectly (see above race).
We also modify the way we manage 'Blocked' to fit better with the new
handling of 'BlockedBadBlocks' and to make it consistent between
externally managed and internally managed metadata. This requires
that each raidXd loop checks if the metadata needs to be written and
triggers a write (md_check_recovery) if needed. Otherwise a queued
write request might cause raidXd to wait for the metadata to write,
and only that thread can write it.
Before writing metadata, we set FaultRecorded for all devices that
are Faulty, then after writing the metadata we clear Blocked for any
device for which the Fault was certainly Recorded.
The 'faulty' device flag now appears in sysfs if the device is faulty
*or* it has unacknowledged bad blocks. So user-space which does not
understand bad blocks can continue to function correctly.
User space which does, should not assume a device is faulty until it
sees the 'faulty' flag, and then sees the list of unacknowledged bad
blocks is empty.
Signed-off-by: NeilBrown <neilb@suse.de>
If a device has ever seen a write error, we will want to handle
known-bad-blocks differently.
So create an appropriate state flag and export it via sysfs.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
When performing resync/etc, keep the size of the request
small enough that it doesn't overlap any known bad blocks.
Devices with badblocks at the start of the request are completely
excluded.
If there is nowhere to read from due to bad blocks, record
a bad block on each target device.
Now that we never read from known-bad-blocks we can allow devices with
known-bad-blocks into a RAID1.
Signed-off-by: NeilBrown <neilb@suse.de>
Now that we have a bad block list, we should not read from those
blocks.
There are several main parts to this:
1/ read_balance needs to check for bad blocks, and return not only
the chosen device, but also how many good blocks are available
there.
2/ fix_read_error needs to avoid trying to read from bad blocks.
3/ read submission must be ready to issue multiple reads to
different devices as different bad blocks on different devices
could mean that a single large read cannot be served by any one
device, but can still be served by the array.
This requires keeping count of the number of outstanding requests
per bio. This count is stored in 'bi_phys_segments'
4/ retrying a read needs to also be ready to submit a smaller read
and queue another request for the rest.
This does not yet handle bad blocks when reading to perform resync,
recovery, or check.
'md_trim_bio' will also be used for RAID10, so put it in md.c and
export it.
Signed-off-by: NeilBrown <neilb@suse.de>
Space must have been allocated when array was created.
A feature flag is set when the badblock list is non-empty, to
ensure old kernels don't load and trust the whole device.
We only update the on-disk badblocklist when it has changed.
If the badblocklist (or other metadata) is stored on a bad block, we
don't cope very well.
If metadata has no room for bad block, flag bad-blocks as disabled,
and do the same for 0.90 metadata.
Signed-off-by: NeilBrown <neilb@suse.de>
As no personality understand bad block lists yet, we must
reject any device that is known to contain bad blocks.
As the personalities get taught, these tests can be removed.
This only applies to raid1/raid5/raid10.
For linear/raid0/multipath/faulty the whole concept of bad blocks
doesn't mean anything so there is no point adding the checks.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
This can show the log (providing it fits in one page) and
allows bad blocks to be 'acknowledged' meaning that they
have safely been recorded in metadata.
Clearing bad blocks is not allowed via sysfs (except for
code testing). A bad block can only be cleared when
a write to the block succeeds.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
This the first step in allowing md to track bad-blocks per-device so
that we can fail individual blocks rather than the whole device.
This patch just adds a data structure for recording bad blocks, with
routines to add, remove, search the list.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
When calling bioset_create we pass the size of the front_pad as
sizeof(mddev)
which looks suspicious as mddev is a pointer and so it looks like a
common mistake where
sizeof(*mddev)
was intended.
The size is actually correct as we want to store a pointer in the
front padding of the bios created by the bioset, so make the intent
more explicit by using
sizeof(mddev_t *)
Reported-by: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This patch causes MD to generate an event (for device-mapper) when the
synchronization thread is reaped. This is expected behavior for device-mapper.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Revert most of commit e384e58549
md/bitmap: prepare for storing write-intent-bitmap via dm-dirty-log.
MD should not need to use DM's dirty log - we decided to use md's
bitmaps instead.
Keeping the DIV_ROUND_UP clean-ups that were part of commit
e384e58549, however.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If device-mapper creates a RAID1 array that includes devices to
be rebuilt, it will deref a NULL pointer when finished because
sysfs is not used by device-mapper instantiated RAID devices.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
While preparing to write a stripe we keep the parity block or blocks
locked (R5_LOCKED) - towards the end of schedule_reconstruction.
If the array is discovered to have failed before this write completes
we can leave those blocks LOCKED, and init_stripe will notice that a
free stripe still has a locked block and will complain.
So clear the R5_LOCKED flag in handle_failed_stripe, and demote the
'BUG' to a 'WARN_ON'.
Signed-off-by: NeilBrown <neilb@suse.de>
Read errors are considered to corrected if write-back and re-read
cycle is finished without further problems. Thus moving the rdev->
corrected_errors counting after the re-reading looks more reasonable
IMHO.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Read errors are considered to corrected if write-back and re-read
cycle is finished without further problems. Thus moving the rdev->
corrected_errors counting after the re-reading looks more reasonable
IMHO.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Read errors are considered to corrected if write-back and re-read
cycle is finished without further problems. Thus moving the rdev->
corrected_errors counting after the re-reading looks more reasonable
IMHO. Also included a couple of whitespace fixes on sync_page_io().
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
page_address() returns void pointer, so the casts can be removed.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Normally we would fail a device with a READ error. However if doing
so causes the array to fail, it is better to leave the device
in place and just return the read error to the caller.
The current test for decide if the array will fail is overly
simplistic.
We have a function 'enough' which can tell if the array is failed or
not, so use it to guide the decision.
Signed-off-by: NeilBrown <neilb@suse.de>
When we get a read error during recovery, RAID10 previously
arranged for the recovering device to appear to fail so that
the recovery stops and doesn't restart. This is misleading and wrong.
Instead, make use of the new recovery_disabled handling and mark
the target device and having recovery disabled.
Add appropriate checks in add_disk and remove_disk so that devices
are removed and not re-added when recovery is disabled.
Signed-off-by: NeilBrown <neilb@suse.de>
If we hit a read error while recovering a mirror, we want to abort the
recovery without necessarily failing the disk - as having a disk this
a read error is better than not having an array at all.
Currently this is managed with a per-array flag "recovery_disabled"
and is only implemented for RAID1. For RAID10 we will need finer
grained control as we might want to disable recovery for individual
devices separately.
So push more of the decision making into the personality.
'recovery_disabled' is now a 'cookie' which is copied when the
personality want to disable recovery and is changed when a device is
added to the array as this is used as a trigger to 'try recovery
again'.
This will allow RAID10 to get the control that it needs.
Signed-off-by: NeilBrown <neilb@suse.de>
Commit c89a8eee61 ("Allow faulty devices to be removed from a
readonly array.") added some work on ro array in the function,
but it couldn't be done since we didn't allow the ro array to be
handled from the beginning. Fix it.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
There are places where sysfs links to rdev are handled
in a same way. Add the helper functions to consolidate
them.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
As per printk_ratelimit comment, it should not be used.
Signed-off-by: Christian Dietrich <christian.dietrich@informatik.uni-erlangen.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Using __test_and_{set,clear}_bit_le() with ignoring its return value
can be replaced with __{set,clear}_bit_le().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: NeilBrown <neilb@suse.de>
Cc: linux-raid@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
handle_stripe5() and handle_stripe6() are now virtually identical.
So discard one and rename the other to 'analyse_stripe()'.
It always returns 0, so change it to 'void' and remove the 'done'
variable in handle_stripe().
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
The RAID6 version of this code is usable for RAID5 providing:
- we test "conf->max_degraded" rather than "2" as appropriate
- we make sure s->failed_num[1] is meaningful (and not '-1')
when s->failed > 1
The 'return 1' must become 'goto finish' in the new location.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Apart from 'prexor' which can only be set for RAID5, and
'qd_idx' which can only be meaningful for RAID6, these two
chunks of code are nearly the same.
So combine them into one adding a test to call either
handle_parity_checks5 or handle_parity_checks6 as appropriate.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
RAID6 is only allowed to choose 'reconstruct-write' while RAID5 is
also allow 'read-modify-write'
Apart from this difference, handle_stripe_dirtying[56] are nearly
identical. So resolve these differences and create just one function.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Provided that ->failed_num[1] is not a valid device number (which is
easily achieved) fetch_block6 provides all the functionality of
fetch_block5.
So remove the latter and rename the former to simply "fetch_block".
Then handle_stripe_fill5 and handle_stripe_fill6 become the same and
can similarly be united.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Next patch will unite fetch_block5 and fetch_block6.
First I want to make the differences a little more clear.
For RAID6 if we are writing at all and there is a failed device, then
we need to load or compute every block so we can do a
reconstruct-write.
This case isn't needed for RAID5 - we will do a read-modify-write in
that case.
So make that test a separate test in fetch_block6 rather than merged
with two other tests.
Make a similar change in fetch_block5 so the one bit that is not
needed for RAID6 is clearly separate.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
The difference between the RAID5 and RAID6 code here is easily
resolved using conf->max_degraded.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Prior to commit ab69ae12ce the code in handle_stripe5 and
handle_stripe6 to "Finish reconstruct operations initiated by the
expansion process" was identical.
That commit added an identical stanza of code to each function, but in
different places. That was careless.
The raid5 code was correct, so move that out into handle_stripe and
remove raid6 version.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
This arg is only used to differentiate between RAID5 and RAID6 but
that is not needed. For RAID5, raid5_compute_sector will set qd_idx
to "~0" so j with certainly not equals qd_idx, so there is no need
for a guard on that condition.
So remove the guard and remove the arg from the declaration and
callers of handle_stripe_expansion.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
By defining the 'stripe_head_state' in 'handle_stripe', we can move
some common code out of handle_stripe[56]() and into handle_stripe.
The means that all accesses for stripe_head_state in handle_stripe[56]
need to be 's->' instead of 's.', but the compiler should inline
those functions and just use a direct stack reference, and future
patches while hoist most of this code up into handle_stripe()
so we will revert to "s.".
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Adding these three fields will allow more common code to be moved
to handle_stripe()
struct field rearrangement by Namhyung Kim.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
'struct stripe_head_state' stores state about the 'current' stripe
that is passed around while handling the stripe.
For RAID6 there is an extension structure: r6_state, which is also
passed around.
There is no value in keeping these separate, so move the fields from
the latter into the former.
This means that all code now needs to treat s->failed_num as an small
array, but this is a small cost.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
There is common code at the start of handle_stripe5 and
handle_stripe6. Move it into handle_stripe.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
sh->lock is now mainly used to ensure that two threads aren't running
in the locked part of handle_stripe[56] at the same time.
That can more neatly be achieved with an 'active' flag which we set
while running handle_stripe. If we find the flag is set, we simply
requeue the stripe for later by setting STRIPE_HANDLE.
For safety we take ->device_lock while examining the state of the
stripe and creating a summary in 'stripe_head_state / r6_state'.
This possibly isn't needed but as shared fields like ->toread,
->towrite are checked it is safer for now at least.
We leave the label after the old 'unlock' called "unlock" because it
will disappear in a few patches, so renaming seems pointless.
This leaves the stripe 'locked' for longer as we clear STRIPE_ACTIVE
later, but that is not a problem.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
Other places that change or follow dev->towrite and dev->written take
the device_lock as well as the sh->lock.
So it should really be held in these places too.
Also, doing so will allow sh->lock to be discarded.
with merged fixes by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
This is the start of a series of patches to remove sh->lock.
sync_request takes sh->lock before setting STRIPE_SYNCING to ensure
there is no race with testing it in handle_stripe[56].
Instead, use a new flag STRIPE_SYNC_REQUESTED and test it early
in handle_stripe[56] (after getting the same lock) and perform the
same set/clear operations if it was set.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (107 commits)
vfs: use ERR_CAST for err-ptr tossing in lookup_instantiate_filp
isofs: Remove global fs lock
jffs2: fix IN_DELETE_SELF on overwriting rename() killing a directory
fix IN_DELETE_SELF on overwriting rename() on ramfs et.al.
mm/truncate.c: fix build for CONFIG_BLOCK not enabled
fs:update the NOTE of the file_operations structure
Remove dead code in dget_parent()
AFS: Fix silly characters in a comment
switch d_add_ci() to d_splice_alias() in "found negative" case as well
simplify gfs2_lookup()
jfs_lookup(): don't bother with . or ..
get rid of useless dget_parent() in btrfs rename() and link()
get rid of useless dget_parent() in fs/btrfs/ioctl.c
fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers
drivers: fix up various ->llseek() implementations
fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek
Ext4: handle SEEK_HOLE/SEEK_DATA generically
Btrfs: implement our own ->llseek
fs: add SEEK_HOLE and SEEK_DATA flags
reiserfs: make reiserfs default to barrier=flush
...
Fix up trivial conflicts in fs/xfs/linux-2.6/xfs_super.c due to the new
shrinker callout for the inode cache, that clashed with the xfs code to
start the periodic workers later.
Moving the event counter into the dynamically allocated 'struc seq_file'
allows poll() support without the need to allocate its own tracking
structure.
All current users are switched over to use the new counter.
Requested-by: Andrew Morton akpm@linux-foundation.org
Acked-by: NeilBrown <neilb@suse.de>
Tested-by: Lucas De Marchi lucas.demarchi@profusion.mobi
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The rcu callback free_conf() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(free_conf).
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NeilBrown <neilb@suse.de>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
In raid5::make_request(), once bio_data_dir(@bi) is detected
it never (and couldn't) be changed. Use the result always.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Replace kmem_cache_alloc + memset(,0,) to kmem_cache_zalloc.
I think it's not harmful since @conf->slab_cache already knows
actual size of struct stripe_head.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When performing a recovery, only first 2 slots in r10_bio are in use,
for read and write respectively. However all of pages in the write bio
are never used and just replaced to read bio's when the read completes.
Get rid of those unused pages and share read pages properly.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When normal-write and sync-read/write bio completes, we should
find out the disk number the bio belongs to. Factor those common
code out to a separate function.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Variable 'first' is initialized to zero and updated to @rdev->raid_disk
only if it is greater than 0. Thus condition '>= first' always implies
'>= 0' so the latter is not needed.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a device fails in a way that causes pending request to take a while
to complete, md will not be able to immediately remove it from the
array in remove_and_add_spares.
It will then incorrectly look like a spare device and md will try to
recover it even though it is failed.
This leads to a recovery process starting and instantly aborting over
and over again.
We should check if the device is faulty before considering it to be a
spare. This will avoid trying to start a recovery that cannot
proceed.
This bug was introduced in 2.6.26 so that patch is suitable for any
kernel since then.
Cc: stable@kernel.org
Reported-by: Jim Paradis <james.paradis@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In the bio_for_each_segment loop, bvl always points current
bio_vec, so the same as bio_iovec_idx(, i). Let's get rid of
it.
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Commit e9c7469bb4 ("md: implment REQ_FLUSH/FUA support")
introduced R5_WantFUA flag and set rw to WRITE_FUA in that case.
However remaining code still checks whether rw is exactly same
as WRITE or not, so FUAed-write ends up with being treated as
READ. Fix it.
This bug has been present since 2.6.37 and the fix is suitable for any
-stable kernel since then. It is not clear why this has not caused
more problems.
Cc: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
The @bio->bi_phys_segments consists of active stripes count in the
lower 16 bits and processed stripes count in the upper 16 bits. So
logical-OR operator should be bitwise one.
This bug has been present since 2.6.27 and the fix is suitable for any
-stable kernel since then. Fortunately the bad code is only used on
error paths and is relatively unlikely to be hit.
Cc: stable@kernel.org
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Get rid of ->syncchunk and ->counter_bits since they're never used.
Also discard COUNTER_BYTE_RATIO which is unused.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Add check to determine if a device needs full resync or if partial resync will do
RAID 5 was assuming that if a device was not In_sync, it must undergo a full
resync. We add a check to see if 'saved_raid_disk' is the same as 'raid_disk'.
If it is, we can safely skip the full resync and rely on the bitmap for
partial recovery instead. This is the legitimate purpose of 'saved_raid_disk',
from md.h:
int saved_raid_disk; /* role that device used to have in the
* array and could again if we did a partial
* resync from the bitmap
*/
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Add bitmap support to the device-mapper specific metadata area.
This patch allows the creation of the bitmap metadata area upon
initial array creation via device-mapper.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Add the 'sync_super' function pointer to MD array structure (struct mddev_s)
If device-mapper (dm-raid.c) is to define its own on-disk superblock and be
able to load it, there must still be a way for MD to initiate superblock
updates. The simplest way to make this happen is to provide a pointer in
the MD array structure that can be set by device-mapper (or other module)
with a function to do this. If the function has been set, it will be used;
otherwise, the method with be looked up via 'super_types' as usual.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
MD RAID1: Changes to allow RAID1 to be used by device-mapper (dm-raid.c)
Added the necessary congestion function and conditionalize calls requiring an
array 'queue' or 'gendisk'.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Move personality and sync/recovery thread starting outside md_run.
Moving the wakeup's of the personality and sync/recovery threads out of
md_run and into do_md_run and mddev_resume solves two issues:
1) It allows bitmap_load to be called before the sync_thread is run and
2) when MD personalities are used by device-mapper (dm-raid.c), the start-up
of the array is better alligned with device-mapper primatives
(CTR/resume/suspend/DTR). I/O - in this case, recovery operations - should
not happen until after a resume has taken place.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Make message a bit clearer by s/blocks/k/
I chose 'k' vs 'kiB' or 'kB' because it is what is used earlier in the
message. 'k' may be a bit ambigous, but I think it's better than "blocks"
which normally means 512, but means 1024 in MD.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Disallow resync I/O while the RAID array is suspended.
Recovery, resync, and metadata I/O should not be allowed while a device is
suspended.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Don't attempt md_integrity_register if there is no gendisk struct available.
When MD arrays are built via device-mapper, the gendisk structure is not
available via mddev.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Return client directly from dm_kcopyd_client_create, not through a
parameter, making it consistent with dm_io_client_create.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Reserve just the minimum of pages needed to process one job.
Because we allocate pages from page allocator, we don't need to reserve
a large number of pages. The maximum job size is SUB_JOB_SIZE and we
calculate the number of reserved pages based on this.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Replace the arbitrary calculation of an initial io struct mempool size
with a constant.
The code calculated the number of reserved structures based on the request
size and used a "magic" multiplication constant of 4. This patch changes
it to reserve a fixed number - itself still chosen quite arbitrarily.
Further testing might show if there is a better number to choose.
Note that if there is no memory pressure, we can still allocate an
arbitrary number of "struct io" structures. One structure is enough to
process the whole request.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch changes dm-kcopyd so that it allocates pages from the main
page allocator with __GFP_NOWARN | __GFP_NORETRY flags (so that it can
fail in case of memory pressure). If the allocation fails, dm-kcopyd
allocates pages from its own reserve.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce a parameter for gfp flags to alloc_pl() for use in following
patches.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove the spinlock protecting the pages allocation. The spinlock is only
taken on initialization or from single-threaded workqueue. Therefore, the
spinlock is useless.
The spinlock is taken in kcopyd_get_pages and kcopyd_put_pages.
kcopyd_get_pages is only called from run_pages_job, which is only
called from process_jobs called from do_work.
kcopyd_put_pages is called from client_alloc_pages (which is initialization
function) or from run_complete_job. run_complete_job is only called from
process_jobs called from do_work.
Another spinlock, kc->job_lock is taken each time someone pushes or pops
some work for the worker thread. Once we take kc->job_lock, we
guarantee that any written memory is visible to the other CPUs.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
There's a possible theoretical deadlock in dm-kcopyd because multiple
allocations from the same mempool are required to finish a request.
Avoid this by preallocating sub jobs.
There is a mempool of 512 entries. Each request requires up to 9
entries from the mempool. If we have at least 57 concurrent requests
running, the mempool may overflow and mempool allocations may start
blocking until another entry is freed to the mempool. Because the same
thread is used to free entries to the mempool and allocate entries from
the mempool, this may result in a deadlock.
This patch changes it so that one mempool entry contains all 9 "struct
kcopyd_job" required to fulfill the whole request. The allocation is
done only once in dm_kcopyd_copy and no further mempool allocations are
done during request processing.
If dm_kcopyd_copy is not run in the completion thread, this
implementation is deadlock-free.
MIN_JOBS needs reducing accordingly and we've chosen to reduce it
further to 8.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Don't split SUB_JOB_SIZE jobs
If the job size equals SUB_JOB_SIZE, there is no point in splitting it.
Splitting it just unnecessarily wastes time, because the split job size
is SUB_JOB_SIZE too.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Integrity errors need to be passed to the owner of the integrity
metadata for processing. Consequently EILSEQ should be passed up the
stack.
Cc: stable@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch adds a check that a block device has a request function
defined before it is used. Otherwise, misconfiguration can cause an oops.
Because we are allowing devices with zero size e.g. an offline multipath
device as in commit 2cd54d9bed
("dm: allow offline devices") there needs to be an additional check
to ensure devices are initialised. Some block devices, like a loop
device without a backing file, exist but have no request function.
Reproducer is trivial: dm-mirror on unbound loop device
(no backing file on loop devices)
dmsetup create x --table "0 8 mirror core 2 8 sync 2 /dev/loop0 0 /dev/loop1 0"
and mirror resync will immediatelly cause OOps.
BUG: unable to handle kernel NULL pointer dereference at (null)
? generic_make_request+0x2bd/0x590
? kmem_cache_alloc+0xad/0x190
submit_bio+0x53/0xe0
? bio_add_page+0x3b/0x50
dispatch_io+0x1ca/0x210 [dm_mod]
? read_callback+0x0/0xd0 [dm_mirror]
dm_io+0xbb/0x290 [dm_mod]
do_mirror+0x1e0/0x748 [dm_mirror]
Signed-off-by: Milan Broz <mbroz@redhat.com>
Reported-by: Zdenek Kabelac <zkabelac@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Permit a target to support discards regardless of whether or not all its
underlying devices do.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
b43: fix comment typo reqest -> request
Haavard Skinnemoen has left Atmel
cris: typo in mach-fs Makefile
Kconfig: fix copy/paste-ism for dell-wmi-aio driver
doc: timers-howto: fix a typo ("unsgined")
perf: Only include annotate.h once in tools/perf/util/ui/browsers/annotate.c
md, raid5: Fix spelling error in comment ('Ofcourse' --> 'Of course').
treewide: fix a few typos in comments
regulator: change debug statement be consistent with the style of the rest
Revert "arm: mach-u300/gpio: Fix mem_region resource size miscalculations"
audit: acquire creds selectively to reduce atomic op overhead
rtlwifi: don't touch with treewide double semicolon removal
treewide: cleanup continuations and remove logging message whitespace
ath9k_hw: don't touch with treewide double semicolon removal
include/linux/leds-regulator.h: fix syntax in example code
tty: fix typo in descripton of tty_termios_encode_baud_rate
xtensa: remove obsolete BKL kernel option from defconfig
m68k: fix comment typo 'occcured'
arch:Kconfig.locks Remove unused config option.
treewide: remove extra semicolons
...
The sysfs attribute 'resync_start' (known internally as recovery_cp),
records where a resync is up to. A value of 0 means the array is
not known to be in-sync at all. A value of MaxSector means the array
is believed to be fully in-sync.
When the size of member devices of an array (RAID1,RAID4/5/6) is
increased, the array can be increased to match. This process sets
resync_start to the old end-of-device offset so that the new part of
the array gets resynced.
However with RAID1 (and RAID6) a resync is not technically necessary
and may be undesirable. So it would be good if the implied resync
after the array is resized could be avoided.
So: change 'resync_start' so the value can be changed while the array
is active, and as a precaution only allow it to be changed while
resync/recovery is 'frozen'. Changing it once resync has started is
not going to be useful anyway.
This allows the array to be resized without a resync by:
write 'frozen' to 'sync_action'
write new size to 'component_size' (this will set resync_start)
write 'none' to 'resync_start'
write 'idle' to 'sync_action'.
Also slightly improve some tests on recovery_cp when resizing
raid1/raid5. Now that an arbitrary value could be set we should be
more careful in our tests.
Signed-off-by: NeilBrown <neilb@suse.de>
When a loop ends with an 'if' with a large body, it is neater
to make the if 'continue' on the inverse condition, and then
the body is indented less.
Apply this pattern 3 times, and wrap some other long lines.
Signed-off-by: NeilBrown <neilb@suse.de>
Currently the rdev on which a read error happened could be removed
before we perform the fix_error handling. This requires extra tests
for NULL.
So delay the rdev_dec_pending call until after the call to
fix_read_error so that we can be sure that the rdev still exists.
This allows an 'if' clause to be removed so the body gets re-indented
back one level.
Signed-off-by: NeilBrown <neilb@suse.de>
The current handling and freeing of these pages is a bit fragile.
We only keep the list of allocated pages in each bio, so we need to
still have a valid bio when freeing the pages, which is a bit clumsy.
So simply store the allocated page list in the r1_bio so it can easily
be found and freed when we are finished with the r1_bio.
Signed-off-by: NeilBrown <neilb@suse.de>
If we get a read error during resync/recovery we current repeat with
single-page reads to find out just where the error is, and possibly
read each page from a different device.
With check/repair we don't currently do that, we just fail.
However it is possible that while all devices fail on the large 64K
read, we might be able to satisfy each 4K from one device or another.
So call fix_sync_read_error before process_checks to maximise the
chance of finding good data and writing it out to the devices with
read errors.
For this to work, we need to set the 'uptodate' flags properly after
fix_sync_read_error has succeeded.
Signed-off-by: NeilBrown <neilb@suse.de>
These changes are mostly cosmetic:
1/ change mddev->raid_disks to conf->raid_disks because the later is
technically safer, though in current practice it doesn't matter in
this particular context.
2/ Rearrange two for / if loops to have an early 'continue' so the
body of the 'if' doesn't need to be indented so much.
Signed-off-by: NeilBrown <neilb@suse.de>
sync_request_write is too big and too deep.
So split out two self-contains bits of functionality into separate
function.
Signed-off-by: NeilBrown <neilb@suse.de>
- there is no need to test_bit Faulty, as that was already done in
md_error which is the only caller of these functions.
- MD_CHANGE_DEVS should be set *after* faulty is set to ensure
metadata is updated correctly.
- spinlock should be held while updating ->degraded.
Signed-off-by: NeilBrown <neilb@suse.de>
