On sparc32, which includes <linux/swap.h> from <asm/pgtable_32.h>:
drivers/md/dm-cache-policy-mq.c:962:13: error: conflicting types for 'remove_mapping'
include/linux/swap.h:285:12: note: previous declaration of 'remove_mapping' was here
As mq_remove_mapping() already exists, and the local remove_mapping() is
used only once, inline it manually to avoid the conflict.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair Kergon <agk@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Both marked for -stable, both since 3.3. I guess I should spend more
time testing...
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Merge tag 'md/3.11-fixes' of git://neil.brown.name/md
Pull md fixes from Neil Brown:
"Two more bugfixes for md in 3.11
Both marked for -stable, both since 3.3. I guess I should spend more
time testing..."
* tag 'md/3.11-fixes' of git://neil.brown.name/md:
md/raid5: fix interaction of 'replace' and 'recovery'.
md/raid10: remove use-after-free bug.
If a device in a RAID4/5/6 is being replaced while another is being
recovered, then the writes to the replacement device currently don't
happen, resulting in corruption when the replacement completes and the
new drive takes over.
This is because the replacement writes are only triggered when
's.replacing' is set and not when the similar 's.sync' is set (which
is the case during resync and recovery - it means all devices need to
be read).
So schedule those writes when s.replacing is set as well.
In this case we cannot use "STRIPE_INSYNC" to record that the
replacement has happened as that is needed for recording that any
parity calculation is complete. So introduce STRIPE_REPLACED to
record if the replacement has happened.
For safety we should also check that STRIPE_COMPUTE_RUN is not set.
This has a similar effect to the "s.locked == 0" test. The latter
ensure that now IO has been flagged but not started. The former
checks if any parity calculation has been flagged by not started.
We must wait for both of these to complete before triggering the
'replace'.
Add a similar test to the subsequent check for "are we finished yet".
This possibly isn't needed (is subsumed in the STRIPE_INSYNC test),
but it makes it more obvious that the REPLACE will happen before we
think we are finished.
Finally if a NeedReplace device is not UPTODATE then that is an
error. We really must trigger a warning.
This bug was introduced in commit 9a3e1101b8
(md/raid5: detect and handle replacements during recovery.)
which introduced replacement for raid5.
That was in 3.3-rc3, so any stable kernel since then would benefit
from this fix.
Cc: stable@vger.kernel.org (3.3+)
Reported-by: qindehua <13691222965@163.com>
Tested-by: qindehua <qindehua@163.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We always need to be careful when calling generic_make_request, as it
can start a chain of events which might free something that we are
using.
Here is one place I wasn't careful enough. If the wbio2 is not in
use, then it might get freed at the first generic_make_request call.
So perform all necessary tests first.
This bug was introduced in 3.3-rc3 (24afd80d99) and can cause an
oops, so fix is suitable for any -stable since then.
Cc: stable@vger.kernel.org (3.3+)
Signed-off-by: NeilBrown <neilb@suse.de>
Pull block IO driver bits from Jens Axboe:
"As I mentioned in the core block pull request, due to real life
circumstances the driver pull request would be late. Now it looks
like -rc2 late... On the plus side, apart form the rsxx update, these
are all things that I could argue could go in later in the cycle as
they are fixes and not features. So even though things are late, it's
not ALL bad.
The pull request contains:
- Updates to bcache, all bug fixes, from Kent.
- A pile of drbd bug fixes (no big features this time!).
- xen blk front/back fixes.
- rsxx driver updates, some of them deferred form 3.10. So should be
well cooked by now"
* 'for-3.11/drivers' of git://git.kernel.dk/linux-block: (63 commits)
bcache: Allocation kthread fixes
bcache: Fix GC_SECTORS_USED() calculation
bcache: Journal replay fix
bcache: Shutdown fix
bcache: Fix a sysfs splat on shutdown
bcache: Advertise that flushes are supported
bcache: check for allocation failures
bcache: Fix a dumb race
bcache: Use standard utility code
bcache: Update email address
bcache: Delete fuzz tester
bcache: Document shrinker reserve better
bcache: FUA fixes
drbd: Allow online change of al-stripes and al-stripe-size
drbd: Constants should be UPPERCASE
drbd: Ignore the exit code of a fence-peer handler if it returns too late
drbd: Fix rcu_read_lock balance on error path
drbd: fix error return code in drbd_init()
drbd: Do not sleep inside rcu
bcache: Refresh usage docs
...
Recent change to use bio_copy_data() in raid1 when repairing
an array is faulty.
The underlying may have changed the bio in various ways using
bio_advance and these need to be undone not just for the 'sbio' which
is being copied to, but also the 'pbio' (primary) which is being
copied from.
So perform the reset on all bios that were read from and do it early.
This also ensure that the sbio->bi_io_vec[j].bv_len passed to
memcmp is correct.
This fixes a crash during a 'check' of a RAID1 array. The crash was
introduced in 3.10 so this is suitable for 3.10-stable.
Cc: stable@vger.kernel.org (3.10)
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit 7ceb17e87b
md: Allow devices to be re-added to a read-only array.
allowed a bit more than just that. It also allows devices to be added
to a read-write array and to end up skipping recovery.
This patch removes the offending piece of code pending a rewrite for a
subsequent release.
More specifically:
If the array has a bitmap, then the device will still need a bitmap
based resync ('saved_raid_disk' is set under different conditions
is a bitmap is present).
If the array doesn't have a bitmap, then this is correct as long as
nothing has been written to the array since the metadata was checked
by ->validate_super. However there is no locking to ensure that there
was no write.
Bug was introduced in 3.10 and causes data corruption so
patch is suitable for 3.10-stable.
Cc: stable@vger.kernel.org (3.10)
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: NeilBrown <neilb@suse.de>
1/ When an different between blocks is found, data is copied from
one bio to the other. However bv_len is used as the length to
copy and this could be zero. So use r10_bio->sectors to calculate
length instead.
Using bv_len was probably always a bit dubious, but the introduction
of bio_advance made it much more likely to be a problem.
2/ When preparing some blocks for sync, we don't set BIO_UPTODATE
except on bios that we schedule for a read. This ensures that
missing/failed devices don't confuse the loop at the top of
sync_request write.
Commit 8be185f2c9 "raid10: Use bio_reset()"
removed a loop which set BIO_UPTDATE on all appropriate bios.
So we need to re-add that flag.
These bugs were introduced in 3.10, so this patch is suitable for
3.10-stable, and can remove a potential for data corruption.
Cc: stable@vger.kernel.org (3.10)
Reported-by: Brassow Jonathan <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
The alloc kthread should've been using try_to_freeze() - and also there
was the potential for the alloc kthread to get woken up after it had
shut down, which would have been bad.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Part of the job of garbage collection is to add up however many sectors
of live data it finds in each bucket, but that doesn't work very well if
it doesn't reset GC_SECTORS_USED() when it starts. Whoops.
This wouldn't have broken anything horribly, but allocation tries to
preferentially reclaim buckets that are mostly empty and that's not
gonna work with an incorrect GC_SECTORS_USED() value.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
The journal replay code starts by finding something that looks like a
valid journal entry, then it does a binary search over the unchecked
region of the journal for the journal entries with the highest sequence
numbers.
Trouble is, the logic was wrong - journal_read_bucket() returns true if
it found journal entries we need, but if the range of journal entries
we're looking for loops around the end of the journal - in that case
journal_read_bucket() could return true when it hadn't found the highest
sequence number we'd seen yet, and in that case the binary search did
the wrong thing. Whoops.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Stopping a cache set is supposed to make it stop attached backing
devices, but somewhere along the way that code got lost. Fixing this
mainly has the effect of fixing our reboot notifier.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
If we stopped a bcache device when we were already detaching (or
something like that), bcache_device_unlink() would try to remove a
symlink from sysfs that was already gone because the bcache dev kobject
had already been removed from sysfs.
So keep track of whether we've removed stuff from sysfs.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
Whoops - bcache's flush/FUA was mostly correct, but flushes get filtered
out unless we say we support them...
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
In the far-too-complicated closure code - closures can have destructors,
for probably dubious reasons; they get run after the closure is no
longer waiting on anything but before dropping the parent ref, intended
just for freeing whatever memory the closure is embedded in.
Trouble is, when remaining goes to 0 and we've got nothing more to run -
we also have to unlock the closure, setting remaining to -1. If there's
a destructor, that unlock isn't doing anything - nobody could be trying
to lock it if we're about to free it - but if the unlock _is needed...
that check for a destructor was racy. Argh.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: linux-stable <stable@vger.kernel.org> # >= v3.10
framework for storage arrays that dynamically reconfigure their
preferred paths for different device regions.
Fix a bug in the verity target that prevented its use with some
specific sizes of devices.
Improve some locking mechanisms in the device-mapper core and bufio.
Add Mike Snitzer as a device-mapper maintainer.
A few more clean-ups and fixes.
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Merge tag 'dm-3.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull device-mapper changes from Alasdair G Kergon:
"Add a device-mapper target called dm-switch to provide a multipath
framework for storage arrays that dynamically reconfigure their
preferred paths for different device regions.
Fix a bug in the verity target that prevented its use with some
specific sizes of devices.
Improve some locking mechanisms in the device-mapper core and bufio.
Add Mike Snitzer as a device-mapper maintainer.
A few more clean-ups and fixes"
* tag 'dm-3.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
dm: add switch target
dm: update maintainers
dm: optimize reorder structure
dm: optimize use SRCU and RCU
dm bufio: submit writes outside lock
dm cache: fix arm link errors with inline
dm verity: use __ffs and __fls
dm flakey: correct ctr alloc failure mesg
dm verity: remove pointless comparison
dm: use __GFP_HIGHMEM in __vmalloc
dm verity: fix inability to use a few specific devices sizes
dm ioctl: set noio flag to avoid __vmalloc deadlock
dm mpath: fix ioctl deadlock when no paths
dm-switch is a new target that maps IO to underlying block devices
efficiently when there is a large number of fixed-sized address regions
but there is no simple pattern to allow for a compact mapping
representation such as dm-stripe.
Though we have developed this target for a specific storage device, Dell
EqualLogic, we have made an effort to keep it as general purpose as
possible in the hope that others may benefit.
Originally developed by Jim Ramsay. Simplified by Mikulas Patocka.
Signed-off-by: Jim Ramsay <jim_ramsay@dell.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This reorder actually improves performance by 20% (from 39.1s to 32.8s)
on x86-64 quad core Opteron.
I have no explanation for this, possibly it makes some other entries are
better cache-aligned.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch removes "io_lock" and "map_lock" in struct mapped_device and
"holders" in struct dm_table and replaces these mechanisms with
sleepable-rcu.
Previously, the code would call "dm_get_live_table" and "dm_table_put" to
get and release table. Now, the code is changed to call "dm_get_live_table"
and "dm_put_live_table". dm_get_live_table locks sleepable-rcu and
dm_put_live_table unlocks it.
dm_get_live_table_fast/dm_put_live_table_fast can be used instead of
dm_get_live_table/dm_put_live_table. These *_fast functions use
non-sleepable RCU, so the caller must not block between them.
If the code changes active or inactive dm table, it must call
dm_sync_table before destroying the old table.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch changes dm-bufio so that it submits write I/Os outside of the
lock. If the number of submitted buffers is greater than the number of
requests on the target queue, submit_bio blocks. We want to block outside
of the lock to improve latency of other threads that may need the lock.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use __always_inline to avoid a link failure with gcc 4.6 on ARM.
gcc 4.7 is OK.
It creates a function block_div.part.8, it references __udivdi3 and
__umoddi3 and it is never called. The references to __udivdi3 and
__umoddi3 cause a link failure.
Reported-by: Rob Herring <robherring2@gmail.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch changes ffs() to __ffs() and fls() to __fls() which don't add
one to the result.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove the reference to the "linear" target from the error message
issued when allocation fails in the flakey target.
Cc: Robin Dong <sanbai@taobao.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove num < 0 test in verity_ctr because num is unsigned.
(Found by Coverity.)
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use __GFP_HIGHMEM in __vmalloc.
Pages allocated with __vmalloc can be allocated in high memory that is not
directly mapped to kernel space, so use __GFP_HIGHMEM just like vmalloc
does. This patch reduces memory pressure slightly because pages can be
allocated in the high zone.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix a boundary condition that caused failure for certain device sizes.
The problem is reported at
http://code.google.com/p/cryptsetup/issues/detail?id=160
For certain device sizes the number of hashes at a specific level was
calculated incorrectly.
It happens for example for a device with data and metadata block size 4096
that has 16385 blocks and algorithm sha256.
The user can test if he is affected by this bug by running the
"veritysetup verify" command and also by activating the dm-verity kernel
driver and reading the whole block device. If it passes without an error,
then the user is not affected.
The condition for the bug is:
Split the total number of data blocks (data_block_bits) into bit strings,
each string has hash_per_block_bits bits. hash_per_block_bits is
rounddown(log2(metadata_block_size/hash_digest_size)). Equivalently, you
can say that you convert data_blocks_bits to 2^hash_per_block_bits base.
If there some zero bit string below the most significant bit string and at
least one bit below this zero bit string is set, then the bug happens.
The same bug exists in the userspace veritysetup tool, so you must use
fixed veritysetup too if you want to use devices that are affected by
this boundary condition.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # 3.4+
Cc: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Set noio flag while calling __vmalloc() because it doesn't fully respect
gfp flags to avoid a possible deadlock (see commit
502624bdad).
This should be backported to stable kernels 3.8 and newer. The kernel 3.8
doesn't have memalloc_noio_save(), so we should set and restore process
flag PF_MEMALLOC instead.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When multipath needs to retry an ioctl the reference to the
current live table needs to be dropped. Otherwise a deadlock
occurs when all paths are down:
- dm_blk_ioctl takes a reference to the current table
and spins in multipath_ioctl().
- A new table is being loaded, but upon resume the process
hangs in dm_table_destroy() waiting for references to
drop to zero.
With this patch the reference to the old table is dropped
prior to retry, thereby avoiding the deadlock.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Pull trivial tree updates from Jiri Kosina:
"The usual stuff from trivial tree"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
treewide: relase -> release
Documentation/cgroups/memory.txt: fix stat file documentation
sysctl/net.txt: delete reference to obsolete 2.4.x kernel
spinlock_api_smp.h: fix preprocessor comments
treewide: Fix typo in printk
doc: device tree: clarify stuff in usage-model.txt.
open firmware: "/aliasas" -> "/aliases"
md: bcache: Fixed a typo with the word 'arithmetic'
irq/generic-chip: fix a few kernel-doc entries
frv: Convert use of typedef ctl_table to struct ctl_table
sgi: xpc: Convert use of typedef ctl_table to struct ctl_table
doc: clk: Fix incorrect wording
Documentation/arm/IXP4xx fix a typo
Documentation/networking/ieee802154 fix a typo
Documentation/DocBook/media/v4l fix a typo
Documentation/video4linux/si476x.txt fix a typo
Documentation/virtual/kvm/api.txt fix a typo
Documentation/early-userspace/README fix a typo
Documentation/video4linux/soc-camera.txt fix a typo
lguest: fix CONFIG_PAE -> CONFIG_x86_PAE in comment
...
The recent comment:
commit 7e83ccbecd
md/raid10: Allow skipping recovery when clean arrays are assembled
Causes raid10 to skip a recovery in certain cases where it is safe to
do so. Unfortunately it also causes a reshape to be skipped which is
never safe. The result is that an attempt to reshape a RAID10 will
appear to complete instantly, but no data will have been moves so the
array will now contain garbage.
(If nothing is written, you can recovery by simple performing the
reverse reshape which will also complete instantly).
Bug was introduced in 3.10, so this is suitable for 3.10-stable.
Cc: stable@vger.kernel.org (3.10)
Cc: Martin Wilck <mwilck@arcor.de>
Signed-off-by: NeilBrown <neilb@suse.de>
There is a bug in 'check_reshape' for raid5.c To checks
that the new minimum number of devices is large enough (which is
good), but it does so also after the reshape has started (bad).
This is bad because
- the calculation is now wrong as mddev->raid_disks has changed
already, and
- it is pointless because it is now too late to stop.
So only perform that test when reshape has not been committed to.
Signed-off-by: NeilBrown <neilb@suse.de>
1/ If a RAID10 is being reshaped to a fewer number of devices
and is stopped while this is ongoing, then when the array is
reassembled the 'mirrors' array will be allocated too small.
This will lead to an access error or memory corruption.
2/ A sanity test for a reshaping RAID10 array is restarted
is slightly incorrect.
Due to the first bug, this is suitable for any -stable
kernel since 3.5 where this code was introduced.
Cc: stable@vger.kernel.org (v3.5+)
Signed-off-by: NeilBrown <neilb@suse.de>
Some of bcache's utility code has made it into the rest of the kernel,
so drop the bcache versions.
Bcache used to have a workaround for allocating from a bio set under
generic_make_request() (if you allocated more than once, the bios you
already allocated would get stuck on current->bio_list when you
submitted, and you'd risk deadlock) - bcache would mask out __GFP_WAIT
when allocating bios under generic_make_request() so that allocation
could fail and it could retry from workqueue. But bio_alloc_bioset() has
a workaround now, so we can drop this hack and the associated error
handling.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Journal writes need to be marked FUA, not just REQ_FLUSH. And btree node
writes have... weird ordering requirements.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Now that we're tracking dirty data per stripe, we can add two
optimizations for raid5/6:
* If a stripe is already dirty, force writes to that stripe to
writeback mode - to help build up full stripes of dirty data
* When flushing dirty data, preferentially write out full stripes first
if there are any.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
To make background writeback aware of raid5/6 stripes, we first need to
track the amount of dirty data within each stripe - we do this by
breaking up the existing sectors_dirty into per stripe atomic_ts
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Previously, dirty_data wouldn't get initialized until the first garbage
collection... which was a bit of a problem for background writeback (as
the PD controller keys off of it) and also confusing for users.
This is also prep work for making background writeback aware of raid5/6
stripes.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
The old lazy sorting code was kind of hacky - rewrite in a way that
mathematically makes more sense; the idea is that the size of the sets
of keys in a btree node should increase by a more or less fixed ratio
from smallest to biggest.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Old gcc doesnt like the struct hack, and it is kind of ugly. So finish
off the work to convert pr_debug() statements to tracepoints, and delete
pkey()/pbtree().
Signed-off-by: Kent Overstreet <koverstreet@google.com>
The tracepoints were reworked to be more sensible, and fixed a null
pointer deref in one of the tracepoints.
Converted some of the pr_debug()s to tracepoints - this is partly a
performance optimization; it used to be that with DEBUG or
CONFIG_DYNAMIC_DEBUG pr_debug() was an empty macro; but at some point it
was changed to an empty inline function.
Some of the pr_debug() statements had rather expensive function calls as
part of the arguments, so this code was getting run unnecessarily even
on non debug kernels - in some fast paths, too.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
The most significant change is that btree reads are now done
synchronously, instead of asynchronously and doing the post read stuff
from a workqueue.
This was originally done because we can't block on IO under
generic_make_request(). But - we already have a mechanism to punt cache
lookups to workqueue if needed, so if we just use that we don't have to
deal with the complexity of doing things asynchronously.
The main benefit is this makes the locking situation saner; we can hold
our write lock on the btree node until we're finished reading it, and we
don't need that btree_node_read_done() flag anymore.
Also, for writes, btree_write() was broken out into btree_node_write()
and btree_leaf_dirty() - the old code with the boolean argument was dumb
and confusing.
The prio_blocked mechanism was improved a bit too, now the only counter
is in struct btree_write, we don't mess with transfering a count from
struct btree anymore.
This required changing garbage collection to block prios at the start
and unblock when it finishes, which is cleaner than what it was doing
anyways (the old code had mostly the same effect, but was doing it in a
convoluted way)
And the btree iter btree_node_read_done() uses was converted to a real
mempool.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
An old version of gcc was complaining about using a const int as the
size of a stack allocated array. Which should be fine - but using
ARRAY_SIZE() is better, anyways.
Also, refactor the code to use scnprintf().
Signed-off-by: Kent Overstreet <koverstreet@google.com>
bio_alloc_bioset returns NULL on failure. This fix adds a missing check
for potential NULL pointer dereferencing.
Signed-off-by: Kumar Amit Mehta <gmate.amit@gmail.com>
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Geert Uytterhoeven