commit 789b5e0315284463617e106baad360cb9e8db3ac upstream.
Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
register_cpu_notifier(&foobar_cpu_notifier);
put_online_cpus();
This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).
Interestingly, the raid5 code can actually prevent double initialization and
hence can use the following simplified form of callback registration:
register_cpu_notifier(&foobar_cpu_notifier);
get_online_cpus();
for_each_online_cpu(cpu)
init_cpu(cpu);
put_online_cpus();
A hotplug operation that occurs between registering the notifier and calling
get_online_cpus(), won't disrupt anything, because the code takes care to
perform the memory allocations only once.
So reorganize the code in raid5 this way to fix the deadlock with callback
registration.
Cc: linux-raid@vger.kernel.org
Fixes: 36d1c6476b
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
[Srivatsa: Fixed the unregister_cpu_notifier() deadlock, added the
free_scratch_buffer() helper to condense code further and wrote the changelog.]
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9f97e4b128d2ea90a5f5063ea0ee3b0911f4c669 upstream.
Before a write starts we set a bit in the write-intent bitmap.
When the write completes we clear that bit if the write was successful
to all devices. However if the write wasn't fully successful we
should not clear the bit. If the faulty drive is subsequently
re-added, the fact that the bit is still set ensure that we will
re-write the data that is missing.
This logic is mediated by the STRIPE_DEGRADED flag - we only clear the
bitmap bit when this flag is not set.
Currently we correctly set the flag if a write starts when some
devices are failed or missing. But we do *not* set the flag if some
device failed during the write attempt.
This is wrong and can result in clearing the bit inappropriately.
So: set the flag when a write fails.
This bug has been present since bitmaps were introduces, so the fix is
suitable for any -stable kernel.
Reported-by: Ethan Wilson <ethan.wilson@shiftmail.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1cc03eb93245e63b0b7a7832165efdc52e25b4e6 upstream.
commit 5d8c71f9e5
md: raid5 crash during degradation
Fixed a crash in an overly simplistic way which could leave
R5_WriteError or R5_MadeGood set in the stripe cache for devices
for which it is no longer relevant.
When those devices are removed and spares added the flags are still
set and can cause incorrect behaviour.
commit 14a75d3e07
md/raid5: preferentially read from replacement device if possible.
Fixed the same bug if a more effective way, so we can now revert
the original commit.
Reported-and-tested-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Fixes: 5d8c71f9e5
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d47648fcf0611812286f68131b40251c6fa54f5e upstream.
SCSI discard will damage discard stripe bio setting, eg, some fields are
changed. If the stripe is reused very soon, we have wrong bios setting. We
remove discard stripe from hash list, so next time the strip will be fully
initialized.
Suitable for backport to 3.7+.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 37c61ff31e9b5e3fcf3cc6579f5c68f6ad40c4b1 upstream.
SCSI layer will add new payload for discard request. If two bios are merged
to one, the second bio has bi_vcnt 1 which is set in raid5. This will confuse
SCSI and cause oops.
Suitable for backport to 3.7+
Reported-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f94c0b6658c7edea8bc19d13be321e3860a3fa54 upstream.
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.
Reported-by: qindehua <13691222965@163.com>
Tested-by: qindehua <qindehua@163.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some tagged for -stable.
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Merge tag 'md-3.10-fixes' of git://neil.brown.name/md
Pull md bugfixes from Neil Brown:
"A few bugfixes for md
Some tagged for -stable"
* tag 'md-3.10-fixes' of git://neil.brown.name/md:
md/raid1,5,10: Disable WRITE SAME until a recovery strategy is in place
md/raid1,raid10: use freeze_array in place of raise_barrier in various places.
md/raid1: consider WRITE as successful only if at least one non-Faulty and non-rebuilding drive completed it.
md: md_stop_writes() should always freeze recovery.
There are cases where the kernel will believe that the WRITE SAME
command is supported by a block device which does not, in fact,
support WRITE SAME. This currently happens for SATA drivers behind a
SAS controller, but there are probably a hundred other ways that can
happen, including drive firmware bugs.
After receiving an error for WRITE SAME the block layer will retry the
request as a plain write of zeroes, but mdraid will consider the
failure as fatal and consider the drive failed. This has the effect
that all the mirrors containing a specific set of data are each
offlined in very rapid succession resulting in data loss.
However, just bouncing the request back up to the block layer isn't
ideal either, because the whole initial request-retry sequence should
be inside the write bitmap fence, which probably means that md needs
to do its own conversion of WRITE SAME to write zero.
Until the failure scenario has been sorted out, disable WRITE SAME for
raid1, raid5, and raid10.
[neilb: added raid5]
This patch is appropriate for any -stable since 3.7 when write_same
support was added.
Cc: stable@vger.kernel.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
The patch that converted raid5 to use bio_reset() forgot to initialize
bi_vcnt.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: NeilBrown <neilb@suse.de>
Cc: linux-raid@vger.kernel.org
Tested-by: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull block core updates from Jens Axboe:
- Major bit is Kents prep work for immutable bio vecs.
- Stable candidate fix for a scheduling-while-atomic in the queue
bypass operation.
- Fix for the hang on exceeded rq->datalen 32-bit unsigned when merging
discard bios.
- Tejuns changes to convert the writeback thread pool to the generic
workqueue mechanism.
- Runtime PM framework, SCSI patches exists on top of these in James'
tree.
- A few random fixes.
* 'for-3.10/core' of git://git.kernel.dk/linux-block: (40 commits)
relay: move remove_buf_file inside relay_close_buf
partitions/efi.c: replace useless kzalloc's by kmalloc's
fs/block_dev.c: fix iov_shorten() criteria in blkdev_aio_read()
block: fix max discard sectors limit
blkcg: fix "scheduling while atomic" in blk_queue_bypass_start
Documentation: cfq-iosched: update documentation help for cfq tunables
writeback: expose the bdi_wq workqueue
writeback: replace custom worker pool implementation with unbound workqueue
writeback: remove unused bdi_pending_list
aoe: Fix unitialized var usage
bio-integrity: Add explicit field for owner of bip_buf
block: Add an explicit bio flag for bios that own their bvec
block: Add bio_alloc_pages()
block: Convert some code to bio_for_each_segment_all()
block: Add bio_for_each_segment_all()
bounce: Refactor __blk_queue_bounce to not use bi_io_vec
raid1: use bio_copy_data()
pktcdvd: Use bio_reset() in disabled code to kill bi_idx usage
pktcdvd: use bio_copy_data()
block: Add bio_copy_data()
...
If we write to a known-bad-block it will be flags as having
a ReadError by analyse_stripe, but the write will proceed anyway
(as it should). Then the read-error handling will kick in an
write again, then re-read.
We don't need that 'write-again', so set R5_ReWrite so it looks like
it has already been done. Then we will just get the re-read, which we
want.
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
As the function call is the most expensive of these tests it should be
done later in the chain so that it can be avoided in some cases.
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This reverts commit 3a366e614d.
Wanlong Gao reports that it causes a kernel panic on his machine several
minutes after boot. Reverting it removes the panic.
Jens says:
"It's not quite clear why that is yet, so I think we should just revert
the commit for 3.9 final (which I'm assuming is pretty close).
The wifi is crap at the LSF hotel, so sending this email instead of
queueing up a revert and pull request."
Reported-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Requested-by: Jens Axboe <axboe@kernel.dk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tejun writes:
-----
This is the pull request for the earlier patchset[1] with the same
name. It's only three patches (the first one was committed to
workqueue tree) but the merge strategy is a bit involved due to the
dependencies.
* Because the conversion needs features from wq/for-3.10,
block/for-3.10/core is based on rc3, and wq/for-3.10 has conflicts
with rc3, I pulled mainline (rc5) into wq/for-3.10 to prevent those
workqueue conflicts from flaring up in block tree.
* Resolving the issue that Jan and Dave raised about debugging
requires arch-wide changes. The patchset is being worked on[2] but
it'll have to go through -mm after these changes show up in -next,
and not included in this pull request.
The three commits are located in the following git branch.
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git writeback-workqueue
Pulling it into block/for-3.10/core produces a conflict in
drivers/md/raid5.c between the following two commits.
e3620a3ad5 ("MD RAID5: Avoid accessing gendisk or queue structs when not available")
2f6db2a707 ("raid5: use bio_reset()")
The conflict is trivial - one removes an "if ()" conditional while the
other removes "rbi->bi_next = NULL" right above it. We just need to
remove both. The merged branch is available at
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq.git block-test-merge
so that you can use it for verification. The test merge commit has
proper merge description.
While these changes are a bit of pain to route, they make code simpler
and even have, while minute, measureable performance gain[3] even on a
workload which isn't particularly favorable to showing the benefits of
this conversion.
----
Fixed up the conflict.
Conflicts:
drivers/md/raid5.c
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- recent regressions in raid5
- recent regressions in dmraid
- a few instances of CONFIG_MULTICORE_RAID456 linger
Several tagged for -stable
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Merge tag 'md-3.9-fixes' of git://neil.brown.name/md
Pull md fixes from NeilBrown:
"A few bugfixes for md
- recent regressions in raid5
- recent regressions in dmraid
- a few instances of CONFIG_MULTICORE_RAID456 linger
Several tagged for -stable"
* tag 'md-3.9-fixes' of git://neil.brown.name/md:
md: remove CONFIG_MULTICORE_RAID456 entirely
md/raid5: ensure sync and DISCARD don't happen at the same time.
MD: Prevent sysfs operations on uninitialized kobjects
MD RAID5: Avoid accessing gendisk or queue structs when not available
md/raid5: schedule_construction should abort if nothing to do.
Had to shuffle the code around a bit (where bi_rw and bi_end_io were
set), but shouldn't really be anything tricky here
Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: NeilBrown <neilb@suse.de>
Bunch of places in the code weren't using it where they could be -
this'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx
into a struct bvec_iter.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: "Ed L. Cashin" <ecashin@coraid.com>
CC: Nick Piggin <npiggin@kernel.dk>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Jim Paris <jim@jtan.com>
CC: Geoff Levand <geoff@infradead.org>
CC: Alasdair Kergon <agk@redhat.com>
CC: dm-devel@redhat.com
CC: Neil Brown <neilb@suse.de>
CC: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Ed Cashin <ecashin@coraid.com>
Just a little convenience macro - main reason to add it now is preparing
for immutable bio vecs, it'll reduce the size of the patch that puts
bi_sector/bi_size/bi_idx into a struct bvec_iter.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Lars Ellenberg <drbd-dev@lists.linbit.com>
CC: Jiri Kosina <jkosina@suse.cz>
CC: Alasdair Kergon <agk@redhat.com>
CC: dm-devel@redhat.com
CC: Neil Brown <neilb@suse.de>
CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
CC: Heiko Carstens <heiko.carstens@de.ibm.com>
CC: linux-s390@vger.kernel.org
CC: Chris Mason <chris.mason@fusionio.com>
CC: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
A number of problems can occur due to races between
resync/recovery and discard.
- if sync_request calls handle_stripe() while a discard is
happening on the stripe, it might call handle_stripe_clean_event
before all of the individual discard requests have completed
(so some devices are still locked, but not all).
Since commit ca64cae960
md/raid5: Make sure we clear R5_Discard when discard is finished.
this will cause R5_Discard to be cleared for the parity device,
so handle_stripe_clean_event() will not be called when the other
devices do become unlocked, so their ->written will not be cleared.
This ultimately leads to a WARN_ON in init_stripe and a lock-up.
- If handle_stripe_clean_event() does clear R5_UPTODATE at an awkward
time for resync, it can lead to s->uptodate being less than disks
in handle_parity_checks5(), which triggers a BUG (because it is
one).
So:
- keep R5_Discard on the parity device until all other devices have
completed their discard request
- make sure we don't try to have a 'discard' and a 'sync' action at
the same time.
This involves a new stripe flag to we know when a 'discard' is
happening, and the use of R5_Overlap on the parity disk so when a
discard is wanted while a sync is active, so we know to wake up
the discard at the appropriate time.
Discard support for RAID5 was added in 3.7, so this is suitable for
any -stable kernel since 3.7.
Cc: stable@vger.kernel.org (v3.7+)
Reported-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Tested-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
MD RAID5: Fix kernel oops when RAID4/5/6 is used via device-mapper
Commit a9add5d (v3.8-rc1) added blktrace calls to the RAID4/5/6 driver.
However, when device-mapper is used to create RAID4/5/6 arrays, the
mddev->gendisk and mddev->queue fields are not setup. Therefore, calling
things like trace_block_bio_remap will cause a kernel oops. This patch
conditionalizes those calls on whether the proper fields exist to make
the calls. (Device-mapper will call trace_block_bio_remap on its own.)
This patch is suitable for the 3.8.y stable kernel.
Cc: stable@vger.kernel.org (v3.8+)
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Since commit 1ed850f356
md/raid5: make sure to_read and to_write never go negative.
It has been possible for handle_stripe_dirtying to be called
when there isn't actually any work to do.
It then calls schedule_reconstruction() which will set R5_LOCKED
on the parity block(s) even when nothing else is happening.
This then causes problems in do_release_stripe().
So add checks to schedule_reconstruction() so that if it doesn't
find anything to do, it just aborts.
This bug was introduced in v3.7, so the patch is suitable
for -stable kernels since then.
Cc: stable@vger.kernel.org (v3.7+)
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
mostly little bugfixes.
Only "feature" is a new RAID10 layout which slightly
improves the number of sets of devices that can concurrently
fail, without data loss.
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Merge tag 'md-3.9' of git://neil.brown.name/md
Pull md updates from NeilBrown:
"Mostly little bugfixes.
Only "feature" is a new RAID10 layout which slightly improves the
number of sets of devices that can concurrently fail, without data
loss."
* tag 'md-3.9' of git://neil.brown.name/md:
md: expedite metadata update when switching read-auto -> active
md: remove CONFIG_MULTICORE_RAID456
md/raid1,raid10: fix deadlock with freeze_array()
md/raid0: improve error message when converting RAID4-with-spares to RAID0
md: raid0: fix error return from create_stripe_zones.
md: fix two bugs when attempting to resize RAID0 array.
DM RAID: Add support for MD's RAID10 "far" and "offset" algorithms
MD RAID10: Improve redundancy for 'far' and 'offset' algorithms (part 2)
MD RAID10: Improve redundancy for 'far' and 'offset' algorithms (part 1)
MD RAID10: Minor non-functional code changes
md: raid1,10: Handle REQ_WRITE_SAME flag in write bios
md: protect against crash upon fsync on ro array
Pull block IO core bits from Jens Axboe:
"Below are the core block IO bits for 3.9. It was delayed a few days
since my workstation kept crashing every 2-8h after pulling it into
current -git, but turns out it is a bug in the new pstate code (divide
by zero, will report separately). In any case, it contains:
- The big cfq/blkcg update from Tejun and and Vivek.
- Additional block and writeback tracepoints from Tejun.
- Improvement of the should sort (based on queues) logic in the plug
flushing.
- _io() variants of the wait_for_completion() interface, using
io_schedule() instead of schedule() to contribute to io wait
properly.
- Various little fixes.
You'll get two trivial merge conflicts, which should be easy enough to
fix up"
Fix up the trivial conflicts due to hlist traversal cleanups (commit
b67bfe0d42ca: "hlist: drop the node parameter from iterators").
* 'for-3.9/core' of git://git.kernel.dk/linux-block: (39 commits)
block: remove redundant check to bd_openers()
block: use i_size_write() in bd_set_size()
cfq: fix lock imbalance with failed allocations
drivers/block/swim3.c: fix null pointer dereference
block: don't select PERCPU_RWSEM
block: account iowait time when waiting for completion of IO request
sched: add wait_for_completion_io[_timeout]
writeback: add more tracepoints
block: add block_{touch|dirty}_buffer tracepoint
buffer: make touch_buffer() an exported function
block: add @req to bio_{front|back}_merge tracepoints
block: add missing block_bio_complete() tracepoint
block: Remove should_sort judgement when flush blk_plug
block,elevator: use new hashtable implementation
cfq-iosched: add hierarchical cfq_group statistics
cfq-iosched: collect stats from dead cfqgs
cfq-iosched: separate out cfqg_stats_reset() from cfq_pd_reset_stats()
blkcg: make blkcg_print_blkgs() grab q locks instead of blkcg lock
block: RCU free request_queue
blkcg: implement blkg_[rw]stat_recursive_sum() and blkg_[rw]stat_merge()
...
I'm not sure why, but the hlist for each entry iterators were conceived
list_for_each_entry(pos, head, member)
The hlist ones were greedy and wanted an extra parameter:
hlist_for_each_entry(tpos, pos, head, member)
Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.
Besides the semantic patch, there was some manual work required:
- Fix up the actual hlist iterators in linux/list.h
- Fix up the declaration of other iterators based on the hlist ones.
- A very small amount of places were using the 'node' parameter, this
was modified to use 'obj->member' instead.
- Coccinelle didn't handle the hlist_for_each_entry_safe iterator
properly, so those had to be fixed up manually.
The semantic patch which is mostly the work of Peter Senna Tschudin is here:
@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;
type T;
expression a,c,d,e;
identifier b;
statement S;
@@
-T b;
<+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
...+>
[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This doesn't seem to actually help and we have an alternate
multi-threading approach waiting in the wings, so just get
rid of this config option and associated code.
As a bonus, we remove one use of CONFIG_EXPERIMENTAL
Cc: Dan Williams <djbw@fb.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: NeilBrown <neilb@suse.de>
bio completion didn't kick block_bio_complete TP. Only dm was
explicitly triggering the TP on IO completion. This makes
block_bio_complete TP useless for tracers which want to know about
bios, and all other bio based drivers skip generating blktrace
completion events.
This patch makes all bio completions via bio_endio() generate
block_bio_complete TP.
* Explicit trace_block_bio_complete() invocation removed from dm and
the trace point is unexported.
* @rq dropped from trace_block_bio_complete(). bios may fly around
w/o queue associated. Verifying and accessing the assocaited queue
belongs to TP probes.
* blktrace now gets both request and bio completions. Make it ignore
bio completions if request completion path is happening.
This makes all bio based drivers generate blktrace completion events
properly and makes the block_bio_complete TP actually useful.
v2: With this change, block_bio_complete TP could be invoked on sg
commands which have bio's with %NULL bi_bdev. Update TP
assignment code to check whether bio->bi_bdev is %NULL before
dereferencing.
Signed-off-by: Tejun Heo <tj@kernel.org>
Original-patch-by: Namhyung Kim <namhyung@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Mostly just little fixes. Probably biggest part is
AVX accelerated RAID6 calculations.
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Merge tag 'md-3.8' of git://neil.brown.name/md
Pull md update from Neil Brown:
"Mostly just little fixes. Probably biggest part is AVX accelerated
RAID6 calculations."
* tag 'md-3.8' of git://neil.brown.name/md:
md/raid5: add blktrace calls
md/raid5: use async_tx_quiesce() instead of open-coding it.
md: Use ->curr_resync as last completed request when cleanly aborting resync.
lib/raid6: build proper files on corresponding arch
lib/raid6: Add AVX2 optimized gen_syndrome functions
lib/raid6: Add AVX2 optimized recovery functions
md: Update checkpoint of resync/recovery based on time.
md:Add place to update ->recovery_cp.
md.c: re-indent various 'switch' statements.
md: close race between removing and adding a device.
md: removed unused variable in calc_sb_1_csm.
Pull block driver update from Jens Axboe:
"Now that the core bits are in, here are the driver bits for 3.8. The
branch contains:
- A huge pile of drbd bits that were dumped from the 3.7 merge
window. Following that, it was both made perfectly clear that
there is going to be no more over-the-wall pulls and how the
situation on individual pulls can be improved.
- A few cleanups from Akinobu Mita for drbd and cciss.
- Queue improvement for loop from Lukas. This grew into adding a
generic interface for waiting/checking an even with a specific
lock, allowing this to be pulled out of md and now loop and drbd is
also using it.
- A few fixes for xen back/front block driver from Roger Pau Monne.
- Partition improvements from Stephen Warren, allowing partiion UUID
to be used as an identifier."
* 'for-3.8/drivers' of git://git.kernel.dk/linux-block: (609 commits)
drbd: update Kconfig to match current dependencies
drbd: Fix drbdsetup wait-connect, wait-sync etc... commands
drbd: close race between drbd_set_role and drbd_connect
drbd: respect no-md-barriers setting also when changed online via disk-options
drbd: Remove obsolete check
drbd: fixup after wait_even_lock_irq() addition to generic code
loop: Limit the number of requests in the bio list
wait: add wait_event_lock_irq() interface
xen-blkfront: free allocated page
xen-blkback: move free persistent grants code
block: partition: msdos: provide UUIDs for partitions
init: reduce PARTUUID min length to 1 from 36
block: store partition_meta_info.uuid as a string
cciss: use check_signature()
cciss: cleanup bitops usage
drbd: use copy_highpage
drbd: if the replication link breaks during handshake, keep retrying
drbd: check return of kmalloc in receive_uuids
drbd: Broadcast sync progress no more often than once per second
drbd: don't try to clear bits once the disk has failed
...
Pull trivial branch from Jiri Kosina:
"Usual stuff -- comment/printk typo fixes, documentation updates, dead
code elimination."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
HOWTO: fix double words typo
x86 mtrr: fix comment typo in mtrr_bp_init
propagate name change to comments in kernel source
doc: Update the name of profiling based on sysfs
treewide: Fix typos in various drivers
treewide: Fix typos in various Kconfig
wireless: mwifiex: Fix typo in wireless/mwifiex driver
messages: i2o: Fix typo in messages/i2o
scripts/kernel-doc: check that non-void fcts describe their return value
Kernel-doc: Convention: Use a "Return" section to describe return values
radeon: Fix typo and copy/paste error in comments
doc: Remove unnecessary declarations from Documentation/accounting/getdelays.c
various: Fix spelling of "asynchronous" in comments.
Fix misspellings of "whether" in comments.
eisa: Fix spelling of "asynchronous".
various: Fix spelling of "registered" in comments.
doc: fix quite a few typos within Documentation
target: iscsi: fix comment typos in target/iscsi drivers
treewide: fix typo of "suport" in various comments and Kconfig
treewide: fix typo of "suppport" in various comments
...
handle_stripe_expansion contains:
if (tx) {
async_tx_ack(tx);
dma_wait_for_async_tx(tx);
}
which is very similar to the body of async_tx_quiesce(),
except that the later handles an error from dma_wait_for_async_tx()
(admittedly by panicing, but that decision belongs in the dma
code, not the md code).
So just us async_tx_quiesce().
Acked-by: Dan Williams <djbw@fb.com>
Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NeilBrown <neilb@suse.de>
New wait_event{_interruptible}_lock_irq{_cmd} macros added. This commit
moves the private wait_event_lock_irq() macro from MD to regular wait
includes, introduces new macro wait_event_lock_irq_cmd() instead of using
the old method with omitting cmd parameter which is ugly and makes a use
of new macros in the MD. It also introduces the _interruptible_ variant.
The use of new interface is when one have a special lock to protect data
structures used in the condition, or one also needs to invoke "cmd"
before putting it to sleep.
All new macros are expected to be called with the lock taken. The lock
is released before sleep and is reacquired afterwards. We will leave the
macro with the lock held.
Note to DM: IMO this should also fix theoretical race on waitqueue while
using simultaneously wait_event_lock_irq() and wait_event() because of
lack of locking around current state setting and wait queue removal.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
commit 9e44476851
MD: raid5 avoid unnecessary zero page for trim
change raid5 to clear R5_Discard when the complete request is
handled rather than when submitting the per-device discard request.
However it did not clear R5_Discard for the parity device.
This means that if the stripe_head was reused before it expired from
the cache, the setting would be wrong and a hang would result.
Also if the R5_Uptodate bit happens to be set, R5_Discard again
won't be cleared. But R5_Uptodate really should be clear at this point.
So make sure R5_Discard is cleared in all cases, and clear
R5_Uptodate when a 'discard' completes.
Signed-off-by: NeilBrown <neilb@suse.de>
stripe_handle.
The chunk of code in stripe_handle which responds to a
*_result value in reconstruct_state is really the completion
of some processing that happened outside of handle_stripe
(possibly asynchronously) and so should be one of the first
things done in handle_stripe().
After the next patch it will be important that it happens before
handle_stripe_clean_event(), as that will clear some dev->flags
bit that this code tests.
Signed-off-by: NeilBrown <neilb@suse.de>
blkdev_issue_discard currently assumes that the granularity
is a power of 2. So in raid5, round the chosen number up to
avoid embarrassment.
Cc: Shaohua Li <shli@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
"discard" support, some dm-raid improvements and other assorted
bits and pieces.
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Merge tag 'md-3.7' of git://neil.brown.name/md
Pull md updates from NeilBrown:
- "discard" support, some dm-raid improvements and other assorted bits
and pieces.
* tag 'md-3.7' of git://neil.brown.name/md: (29 commits)
md: refine reporting of resync/reshape delays.
md/raid5: be careful not to resize_stripes too big.
md: make sure manual changes to recovery checkpoint are saved.
md/raid10: use correct limit variable
md: writing to sync_action should clear the read-auto state.
Subject: [PATCH] md:change resync_mismatches to atomic64_t to avoid races
md/raid5: make sure to_read and to_write never go negative.
md: When RAID5 is dirty, force reconstruct-write instead of read-modify-write.
md/raid5: protect debug message against NULL derefernce.
md/raid5: add some missing locking in handle_failed_stripe.
MD: raid5 avoid unnecessary zero page for trim
MD: raid5 trim support
md/bitmap:Don't use IS_ERR to judge alloc_page().
md/raid1: Don't release reference to device while handling read error.
raid: replace list_for_each_continue_rcu with new interface
add further __init annotations to crypto/xor.c
DM RAID: Fix for "sync" directive ineffectiveness
DM RAID: Fix comparison of index and quantity for "rebuild" parameter
DM RAID: Add rebuild capability for RAID10
DM RAID: Move 'rebuild' checking code to its own function
...
When a RAID5 is reshaping, conf->raid_disks is increased
before mddev->delta_disks becomes zero.
This can result in check_reshape calling resize_stripes with a
number that is too large. This particularly happens
when md_check_recovery calls ->check_reshape().
If we use ->previous_raid_disks, we don't risk this.
Signed-off-by: NeilBrown <neilb@suse.de>
Now that multiple threads can handle stripes, it is safer to
use an atomic64_t for resync_mismatches, to avoid update races.
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
to_read and to_write are part of the result of analysing
a stripe before handling it.
Their use is to avoid some loops and tests if the values are
known to be zero. Thus it is not a problem if they are a
little bit larger than they should be.
So decrementing them in handle_failed_stripe serves little value, and
due to races it could cause some loops to be skipped incorrectly.
So remove those decrements.
Reported-by: "Jianpeng Ma" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
The pr_debug in add_stripe_bio could race with something
changing *bip, so it is best to hold the lock until
after the pr_debug.
Reported-by: "Jianpeng Ma" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We really should hold the stripe_lock while accessing
'toread' else we could race with add_stripe_bio and corrupt
a list.
Reported-by: "Jianpeng Ma" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We want to avoid zero discarded dev page, because it's useless for discard.
But if we don't zero it, another read/write hit such page in the cache and will
get inconsistent data.
To avoid zero the page, we don't set R5_UPTODATE flag after construction is
done. In this way, discard write request is still issued and finished, but read
will not hit the page. If the stripe gets accessed soon, we need reread the
stripe, but since the chance is low, the reread isn't a big deal.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Discard for raid4/5/6 has limitation. If discard request size is
small, we do discard for one disk, but we need calculate parity and
write parity disk. To correctly calculate parity, zero_after_discard
must be guaranteed. Even it's true, we need do discard for one disk
but write another disks, which makes the parity disks wear out
fast. This doesn't make sense. So an efficient discard for raid4/5/6
should discard all data disks and parity disks, which requires the
write pattern to be (A, A+chunk_size, A+chunk_size*2...). If A's size
is smaller than chunk_size, such pattern is almost impossible in
practice. So in this patch, I only handle the case that A's size
equals to chunk_size. That is discard request should be aligned to
stripe size and its size is multiple of stripe size.
Since we can only handle request with specific alignment and size (or
part of the request fitting stripes), we can't guarantee
zero_after_discard even zero_after_discard is true in low level
drives.
The block layer doesn't send down correctly aligned requests even
correct discard alignment is set, so I must filter out.
For raid4/5/6 parity calculation, if data is 0, parity is 0. So if
zero_after_discard is true for all disks, data is consistent after
discard. Otherwise, data might be lost. Let's consider a scenario:
discard a stripe, write data to one disk and write parity disk. The
stripe could be still inconsistent till then depending on using data
from other data disks or parity disks to calculate new parity. If the
disk is broken, we can't restore it. So in this patch, we only enable
discard support if all disks have zero_after_discard.
If discard fails in one disk, we face the similar inconsistent issue
above. The patch will make discard follow the same path as normal
write request. If discard fails, a resync will be scheduled to make
the data consistent. This isn't good to have extra writes, but data
consistency is important.
If a subsequent read/write request hits raid5 cache of a discarded
stripe, the discarded dev page should have zero filled, so the data is
consistent. This patch will always zero dev page for discarded request
stripe. This isn't optimal because discard request doesn't need such
payload. Next patch will avoid it.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Change the thread parameter, so the thread can carry extra info. Next patch
will use it.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit b17459c050
raid5: add a per-stripe lock
added a spin_lock to the 'stripe_head' struct.
Unfortunately there are two places where this struct is allocated
but the spin lock was only initialised in one of them.
So add the missing spin_lock_init.
Signed-off-by: NeilBrown <neilb@suse.de>
When a replacement device becomes active, we mark the device that it
replaces as 'faulty' so that it can subsequently get removed.
However 'calc_degraded' only pays attention to the primary device, not
the replacement, so the array appears to become degraded, which is
wrong.
So teach 'calc_degraded' to consider any replacement if a primary
device is faulty.
This is suitable for -stable as an incorrect 'degraded' value can
confuse md and could lead to data corruption.
This is only relevant for 3.3 and later.
Cc: stable@vger.kernel.org
Reported-by: Robin Hill <robin@robinhill.me.uk>
Reported-by: John Drescher <drescherjm@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This reverts commit 895e3c5c58.
While this patch seemed like a good idea and did help some workloads,
it hurts other workloads.
Large sequential O_DIRECT writes were faster,
Small random O_DIRECT writes were slower.
Other changes (batching RAID5 writes) have improved the sequential
writes using a different mechanism, so the net result of this patch
is definitely negative. So revert it.
Reported-by: Shaohua Li <shli@kernel.org>
Tested-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Peter Zijlstra
Oleg Nesterov
NeilBrown
Shaohua Li
Linus Torvalds
H. Peter Anvin
Kent Overstreet
majianpeng
Jens Axboe
Jonathan Brassow
Sasha Levin
Tejun Heo
Lukas Czerner
Masanari Iida
Alexander Lyakas