Check the return of mddev_find(), since it may fail due to out of
memeory or out of usable minor number.
The reason I chose -ENODEV instead of -ENOMEM or something else is
md_alloc() function chose that ;)
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Properly initialize MD recovery flags when resuming device-mapper devices.
When a device-mapper device is suspended, all I/O must stop. This is done by
calling 'md_stop_writes' and 'mddev_suspend'. These calls in-turn manipulate
the recovery flags - including setting 'MD_RECOVERY_FROZEN'. The DM device
may have been suspended while recovery was not yet complete, so the process
needs to pick-up where it left off. Since 'mddev_resume' does not unset
'MD_RECOVERY_FROZEN' and set 'MD_RECOVERY_NEEDED', we must do it ourselves.
'MD_RECOVERY_NEEDED' can safely be set in 'mddev_resume', but 'MD_RECOVERY_FROZEN'
must be set outside of 'mddev_resume' due to how MD handles RAID reshaping.
(e.g. It is possible for a user to delay reshaping a RAID5->RAID6 by purposefully
setting 'MD_RECOVERY_FROZEN'. Clearing it in 'mddev_resume' would override the
desired behavior.)
Because 'mddev_resume' already unconditionally calls 'md_wakeup_thread(mddev->thread)'
there is no need to make this call from 'raid_resume' since it calls 'mddev_resume'.
Also clean up where level_store calls mddev_resume() - it current
duplicates some of the funcitons of that call. - NB
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Now that bitmaps can be resized, we can allow an array to be resized
while the bitmap is present.
This only covers resizing that involves changing the effective size
of member devices, not resizing that changes the number of devices.
Signed-off-by: NeilBrown <neilb@suse.de>
This new 'struct bitmap_storage' reflects the external storage of the
bitmap.
Having this clearly defined will make it easier to change the storage
used while the array is active.
Signed-off-by: NeilBrown <neilb@suse.de>
An md bitmap comprises two parts
- internal counting of active writes per 'chunk'.
- external storage of whether there are any active writes on
each chunk
The second requires the first, but the first doesn't require the
second.
Not having backing storage means that the bitmap cannot expedite
resync after a crash, but it still allows us to expedite the recovery
of a recently-removed device.
So: allow a bitmap to exist even if there is no backing device.
In that case we default to 128M chunks.
A particular value of this is that we can remove and re-add a bitmap
(possibly of a different granularity) on a degraded array, and not
lose the information needed to fast-recover the missing device.
We don't actually activate these bitmaps yet - that will come
in a later patch.
Signed-off-by: NeilBrown <neilb@suse.de>
If we are to allow bitmaps to be resized when the array is resized,
we need to know how much space there is.
So create an attribute to store this information and set appropriate
defaults.
It can be set more precisely via sysfs, or future metadata extensions
may allow it to be recorded.
Signed-off-by: NeilBrown <neilb@suse.de>
This ensures that it is always freed - there were case where
we failed to free the page.
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
dm-raid currently open-codes the freeing of some members of
and rdev. It is more maintainable to have it call common code
from md.c which does this for all call-sites.
So remove free_disk_sb to md_rdev_clear, export it, and use it in
dm-raid.c
Signed-off-by: NeilBrown <neilb@suse.de>
Some resync type operations need to act on the address space of the
device, others on the address space of the array.
This only affects RAID10, so it sets resync_max_sectors to the array
size (it defaults to the device size), and that is currently used for
resync only. However reshape of a RAID10 must be done against the
array size, not device size, so change code to use resync_max_sectors
for both the resync and the reshape cases.
This does not affect RAID5 or RAID1, just RAID10.
Signed-off-by: NeilBrown <neilb@suse.de>
Some code in raid1 and raid10 use sync_page_io to
read/write pages when responding to read errors.
As we will shortly support changing data_offset for
raid10, this function must understand new_data_offset.
So add that understanding.
Signed-off-by: NeilBrown <neilb@suse.de>
When reshaping we can avoid costly intermediate backup by
changing the 'start' address of the array on the device
(if there is enough room).
So as a first step, allow such a change to be requested
through sysfs, and recorded in v1.x metadata.
(As we didn't previous check that all 'pad' fields were zero,
we need a new FEATURE flag for this.
A (belatedly) check that all remaining 'pad' fields are
zero to avoid a repeat of this)
The new data offset must be requested separately for each device.
This allows each to have a different change in the data offset.
This is not likely to be used often but as data_offset can be
set per-device, new_data_offset should be too.
This patch also removes the 'acknowledged' arg to rdev_set_badblocks as
it is never used and never will be. At the same time we add a new
arg ('in_new') which is currently always zero but will be used more
soon.
When a reshape finishes we will need to update the data_offset
and rdev->sectors. So provide an exported function to do that.
Signed-off-by: NeilBrown <neilb@suse.de>
Currently a reshape operation always progresses from the start
of the array to the end unless the number of devices is being
reduced, in which case it progressed in the opposite direction.
To reverse a partial reshape which changes the number of devices
you can stop the array and re-assemble with the raid-disks numbers
reversed and it will undo.
However for a reshape that does not change the number of devices
it is not possible to reverse the reshape in the middle - you have to
wait until it completes.
So add a 'reshape_direction' attribute with is either 'forwards' or
'backwards' and can be explicitly set when delta_disks is zero.
This will become more important when we allow the data_offset to
change in a reshape. Then the explicit statement of what direction is
being used will be more useful.
This can be enabled in raid5 trivially as it already supports
reverse reshape and just needs to use a different trigger to request it.
Signed-off-by: NeilBrown <neilb@suse.de>
A flush request is usually issued in transaction commit code path, so
using GFP_KERNEL to allocate memory for flush request bio falls into
the classic deadlock issue.
This is suitable for any -stable kernel to which it applies as it
avoids a possible deadlock.
Cc: stable@vger.kernel.org
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Use del_timer_sync to remove timer before mddev_suspend finishes.
We don't want a timer going off after an mddev_suspend is called. This is
especially true with device-mapper, since it can call the destructor function
immediately following a suspend. This results in the removal (kfree) of the
structures upon which the timer depends - resulting in a very ugly panic.
Therefore, we add a del_timer_sync to mddev_suspend to prevent this.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
commit c744a65c1e
md: don't set md arrays to readonly on shutdown.
removed the possibility of a 'BUG' when data is written to an array
that has just been switched to read-only, but also introduced the
possibility that the array metadata could be corrupted.
If, when md_notify_reboot gets the mddev lock, the array is
in a state where it is assembled but hasn't been started (as can
happen if the personality module is not available, or in other unusual
situations), then incorrect metadata will be written out making it
impossible to re-assemble the array.
So only call __md_stop_writes() if the array has actually been
activated.
This patch is needed for any stable kernel which has had the above
commit applied.
Cc: stable@vger.kernel.org
Reported-by: Christoph Nelles <evilazrael@evilazrael.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Commit 7bfec5f35c
md/raid5: If there is a spare and a want_replacement device, start replacement.
cause md_check_recovery to call ->add_disk much more often.
Instead of only when the array is degraded, it is now called whenever
md_check_recovery finds anything useful to do, which includes
updating the metadata for clean<->dirty transition.
This causes unnecessary work, and causes info messages from ->add_disk
to be reported much too often.
So refine md_check_recovery to only do any actual recovery checking
(including ->add_disk) if MD_RECOVERY_NEEDED is set.
This fix is suitable for 3.3.y:
Cc: stable@vger.kernel.org
Reported-by: Jan Ceuleers <jan.ceuleers@computer.org>
Signed-off-by: NeilBrown <neilb@suse.de>
If there are no unacked bad blocks, then there is no point searching
for them to acknowledge them.
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In super_1_sync (the first hunk) we need to clear 'changed' before
checking read_seqretry(), otherwise we might race with other code
adding a bad block and so won't retry later.
In md_update_sb (the second hunk), in the case where there is no
metadata (neither persistent nor external), we treat any bad blocks as
an error. However we need to clear the 'changed' flag before calling
md_ack_all_badblocks, else it won't do anything.
This patch is suitable for -stable release 3.0 and later.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
The part of /proc/mdstat which describes the bitmap should really
be generated by code in bitmap.c. So move it there.
Signed-off-by: NeilBrown <neilb@suse.de>
Currently we don't honour merge_bvec_fn in member devices so if there
is one, we force all requests to be single-page at most.
This is not ideal.
So enhance the raid10 merge_bvec_fn to check that function in children
as well.
This introduces a small problem. There is no locking around calls
the ->merge_bvec_fn and subsequent calls to ->make_request. So a
device added between these could end up getting a request which
violates its merge_bvec_fn.
Currently the best we can do is synchronize_sched(). This will work
providing no preemption happens. If there is preemption, we just
have to hope that new devices are largely consistent with old devices.
Signed-off-by: NeilBrown <neilb@suse.de>
md.h has an 'rdev_for_each()' macro for iterating the rdevs in an
mddev. However it uses the 'safe' version of list_for_each_entry,
and so requires the extra variable, but doesn't include 'safe' in the
name, which is useful documentation.
Consequently some places use this safe version without needing it, and
many use an explicity list_for_each entry.
So:
- rename rdev_for_each to rdev_for_each_safe
- create a new rdev_for_each which uses the plain
list_for_each_entry,
- use the 'safe' version only where needed, and convert all other
list_for_each_entry calls to use rdev_for_each.
Signed-off-by: NeilBrown <neilb@suse.de>
It seems that with recent kernel, writeback can still be happening
while shutdown is happening, and consequently data can be written
after the md reboot notifier switches all arrays to read-only.
This causes a BUG.
So don't switch them to read-only - just mark them clean and
set 'safemode' to '2' which mean that immediately after any
write the array will be switch back to 'clean'.
This could result in the shutdown happening when array is marked
dirty, thus forcing a resync on reboot. However if you reboot
without performing a "sync" first, you get to keep both halves.
This is suitable for any stable kernel (though there might be some
conflicts with obvious fixes in earlier kernels).
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Some simple md-related fixes.
1/ two small fixes to ensure we handle an interrupted resync properly.
2/ avoid loading the bitmap multiple times in dm-raid
* tag 'md-3.3-fixes' of git://neil.brown.name/md:
md: two small fixes to handling interrupt resync.
Prevent DM RAID from loading bitmap twice.
1/ If a resync is aborted we should record how far we got
(recovery_cp) the last request that we know has completed
(->curr_resync_completed) rather than the last request that was
submitted (->curr_resync).
2/ When a resync aborts we still want to update the metadata with
any changes, so set MD_CHANGE_DEVS even if we 'skip'.
Signed-off-by: NeilBrown <neilb@suse.de>
* 'for-3.3/core' of git://git.kernel.dk/linux-block: (37 commits)
Revert "block: recursive merge requests"
block: Stop using macro stubs for the bio data integrity calls
blockdev: convert some macros to static inlines
fs: remove unneeded plug in mpage_readpages()
block: Add BLKROTATIONAL ioctl
block: Introduce blk_set_stacking_limits function
block: remove WARN_ON_ONCE() in exit_io_context()
block: an exiting task should be allowed to create io_context
block: ioc_cgroup_changed() needs to be exported
block: recursive merge requests
block, cfq: fix empty queue crash caused by request merge
block, cfq: move icq creation and rq->elv.icq association to block core
block, cfq: restructure io_cq creation path for io_context interface cleanup
block, cfq: move io_cq exit/release to blk-ioc.c
block, cfq: move icq cache management to block core
block, cfq: move io_cq lookup to blk-ioc.c
block, cfq: move cfqd->icq_list to request_queue and add request->elv.icq
block, cfq: reorganize cfq_io_context into generic and cfq specific parts
block: remove elevator_queue->ops
block: reorder elevator switch sequence
...
Fix up conflicts in:
- block/blk-cgroup.c
Switch from can_attach_task to can_attach
- block/cfq-iosched.c
conflict with now removed cic index changes (we now use q->id instead)
