30 Sep, 2020
1 commit
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Signed-off-by: Qinglang Miao
Signed-off-by: Mike Snitzer
05 Aug, 2020
1 commit
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Pull uninitialized_var() macro removal from Kees Cook:
"This is long overdue, and has hidden too many bugs over the years. The
series has several "by hand" fixes, and then a trivial treewide
replacement.- Clean up non-trivial uses of uninitialized_var()
- Update documentation and checkpatch for uninitialized_var() removal
- Treewide removal of uninitialized_var()"
* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
compiler: Remove uninitialized_var() macro
treewide: Remove uninitialized_var() usage
checkpatch: Remove awareness of uninitialized_var() macro
mm/debug_vm_pgtable: Remove uninitialized_var() usage
f2fs: Eliminate usage of uninitialized_var() macro
media: sur40: Remove uninitialized_var() usage
KVM: PPC: Book3S PR: Remove uninitialized_var() usage
clk: spear: Remove uninitialized_var() usage
clk: st: Remove uninitialized_var() usage
spi: davinci: Remove uninitialized_var() usage
ide: Remove uninitialized_var() usage
rtlwifi: rtl8192cu: Remove uninitialized_var() usage
b43: Remove uninitialized_var() usage
drbd: Remove uninitialized_var() usage
x86/mm/numa: Remove uninitialized_var() usage
docs: deprecated.rst: Add uninitialized_var()
17 Jul, 2020
1 commit
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Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/Reviewed-by: Leon Romanovsky # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe # IB
Acked-by: Kalle Valo # wireless drivers
Reviewed-by: Chao Yu # erofs
Signed-off-by: Kees Cook
01 Jul, 2020
1 commit
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generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.Signed-off-by: Christoph Hellwig
Signed-off-by: Jens Axboe
16 Jan, 2020
1 commit
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Logical block size has type unsigned short. That means that it can be at
most 32768. However, there are architectures that can run with 64k pages
(for example arm64) and on these architectures, it may be possible to
create block devices with 64k block size.For exmaple (run this on an architecture with 64k pages):
Mount will fail with this error because it tries to read the superblock using 2-sector
access:
device-mapper: writecache: I/O is not aligned, sector 2, size 1024, block size 65536
EXT4-fs (dm-0): unable to read superblockThis patch changes the logical block size from unsigned short to unsigned
int to avoid the overflow.Cc: stable@vger.kernel.org
Reviewed-by: Martin K. Petersen
Reviewed-by: Ming Lei
Signed-off-by: Mikulas Patocka
Signed-off-by: Jens Axboe
04 Apr, 2018
1 commit
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Move dm-bufio.h to include/linux/ so that external GPL'd DM target
modules can use it.It is better to allow the use of dm-bufio than force external modules
to implement the equivalent buffered IO mechanism in some new way. The
hope is this will encourage the use of dm-bufio; which will then make it
easier for a GPL'd external DM target module to be included upstream.A couple dm-bufio EXPORT_SYMBOL exports have also been updated to use
EXPORT_SYMBOL_GPL.Signed-off-by: Mikulas Patocka
Signed-off-by: Mike Snitzer
31 May, 2017
1 commit
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Commit b685d3d65ac7 ("block: treat REQ_FUA and REQ_PREFLUSH as
synchronous") removed REQ_SYNC flag from WRITE_{FUA|PREFLUSH|...}
definitions. generic_make_request_checks() however strips REQ_FUA and
REQ_PREFLUSH flags from a bio when the storage doesn't report volatile
write cache and thus write effectively becomes asynchronous which can
lead to performance regressions.Fix the problem by making sure all bios which are synchronous are
properly marked with REQ_SYNC.Fixes: b685d3d65ac7 ("block: treat REQ_FUA and REQ_PREFLUSH as synchronous")
Cc: stable@vger.kernel.org
Signed-off-by: Jan Kara
Signed-off-by: Mike Snitzer
01 Nov, 2016
1 commit
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Remove the WRITE_* and READ_SYNC wrappers, and just use the flags
directly. Where applicable this also drops usage of the
bio_set_op_attrs wrapper.Signed-off-by: Christoph Hellwig
Signed-off-by: Jens Axboe
08 Jun, 2016
1 commit
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Separate the op from the rq_flag_bits and have dm
set/get the bio using bio_set_op_attrs/bio_op.Signed-off-by: Mike Christie
Reviewed-by: Hannes Reinecke
Signed-off-by: Jens Axboe
09 Jan, 2016
1 commit
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When there is an error copying a chunk dm-snapshot can incorrectly hold
associated bios indefinitely, resulting in hung IO.The function copy_callback sets pe->error if there was error copying the
chunk, and then calls complete_exception. complete_exception calls
pending_complete on error, otherwise it calls commit_exception with
commit_callback (and commit_callback calls complete_exception).The persistent exception store (dm-snap-persistent.c) assumes that calls
to prepare_exception and commit_exception are paired.
persistent_prepare_exception increases ps->pending_count and
persistent_commit_exception decreases it.If there is a copy error, persistent_prepare_exception is called but
persistent_commit_exception is not. This results in the variable
ps->pending_count never returning to zero and that causes some pending
exceptions (and their associated bios) to be held forever.Fix this by unconditionally calling commit_exception regardless of
whether the copy was successful. A new "valid" parameter is added to
commit_exception -- when the copy fails this parameter is set to zero so
that the chunk that failed to copy (and all following chunks) is not
recorded in the snapshot store. Also, remove commit_callback now that
it is merely a wrapper around pending_complete.Signed-off-by: Mikulas Patocka
Signed-off-by: Mike Snitzer
Cc: stable@vger.kernel.org
05 Nov, 2015
1 commit
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Pull device mapper updates from Mike Snitzer:
"Smaller set of DM changes for this merge. I've based these changes on
Jens' for-4.4/reservations branch because the associated DM changes
required it.- Revert a dm-multipath change that caused a regression for
unprivledged users (e.g. kvm guests) that issued ioctls when a
multipath device had no available paths.- Include Christoph's refactoring of DM's ioctl handling and add
support for passing through persistent reservations with DM
multipath.- All other changes are very simple cleanups"
* tag 'dm-4.4-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm switch: simplify conditional in alloc_region_table()
dm delay: document that offsets are specified in sectors
dm delay: capitalize the start of an delay_ctr() error message
dm delay: Use DM_MAPIO macros instead of open-coded equivalents
dm linear: remove redundant target name from error messages
dm persistent data: eliminate unnecessary return values
dm: eliminate unused "bioset" process for each bio-based DM device
dm: convert ffs to __ffs
dm: drop NULL test before kmem_cache_destroy() and mempool_destroy()
dm: add support for passing through persistent reservations
dm: refactor ioctl handling
Revert "dm mpath: fix stalls when handling invalid ioctls"
dm: initialize non-blk-mq queue data before queue is used
01 Nov, 2015
1 commit
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ffs counts bit starting with 1 (for the least significant bit), __ffs
counts bits starting with 0. This patch changes various occurrences of ffs
to __ffs and removes subtraction of 1 from the result.Note that __ffs (unlike ffs) is not defined when called with zero
argument, but it is not called with zero argument in any of these cases.Signed-off-by: Mikulas Patocka
Signed-off-by: Mike Snitzer
14 Oct, 2015
1 commit
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If an unsupported option is given then the early return from
persistent_ctr() leaked memory allocated for the 'pstore' and never
destroyed the 'metadata_wq'.Fixes: b0d3cc011e53 ("dm snapshot: add new persistent store option to support overflow")
Signed-off-by: Sudip Mukherjee
Signed-off-by: Mike Snitzer
10 Oct, 2015
1 commit
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Commit 76c44f6d80 introduced the possibly for "Overflow" to be reported
by the snapshot device's status. Older userspace (e.g. lvm2) does not
handle the "Overflow" status response.Fix this incompatibility by requiring newer userspace code, that can
cope with "Overflow", request the persistent store with overflow support
by using "PO" (Persistent with Overflow) for the snapshot store type.Reported-by: Zdenek Kabelac
Fixes: 76c44f6d80 ("dm snapshot: don't invalidate on-disk image on snapshot write overflow")
Reviewed-by: Mikulas Patocka
Signed-off-by: Mike Snitzer
12 Aug, 2015
1 commit
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IS_ERR() already contains an 'unlikely' compiler flag so there is no
need to do that again from IS_ERR() callers.Signed-off-by: Viresh Kumar
Signed-off-by: Mike Snitzer
10 Feb, 2015
1 commit
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The vfree() function performs input parameter validation.
Thus the NULL pointer test around vfree() calls is not needed.This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring
Signed-off-by: Mike Snitzer
04 Mar, 2014
1 commit
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Commit 55494bf2947dccdf2 ("dm snapshot: use dm-bufio") broke snapshots.
Before that 3.14-rc1 commit, loading a snapshot's list of exceptions
involved reading exception areas one by one into ps->area and inserting
those exceptions into the hash table. Commit 55494bf2947dccdf2 changed
it so that dm-bufio with prefetch is used to load exceptions in batchs.
Exceptions are loaded correctly, but ps->area is left uninitialized.
When a new exception is allocated, it is stored in this uninitialized
ps->area which will be written to the disk. This causes metadata
corruption.Fix this corruption by copying the last area that was read via dm-bufio
into ps->area.Signed-off-by: Mikulas Patocka
Signed-off-by: Mike Snitzer
15 Jan, 2014
3 commits
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This patch modifies dm-snapshot so that it prefetches the buffers when
loading the exceptions.The number of buffers read ahead is specified in the DM_PREFETCH_CHUNKS
macro. The current value for DM_PREFETCH_CHUNKS (12) was found to
provide the best performance on a single 15k SCSI spindle. In the
future we may modify this default or make it configurable.Also, introduce the function dm_bufio_set_minimum_buffers to setup
bufio's number of internal buffers before freeing happens. dm-bufio may
hold more buffers if enough memory is available. There is no guarantee
that the specified number of buffers will be available - if you need a
guarantee, use the argument reserved_buffers for
dm_bufio_client_create.Signed-off-by: Mikulas Patocka
Signed-off-by: Mike Snitzer -
Use dm-bufio for initial loading of the exceptions.
Introduce a new function dm_bufio_forget that frees the given buffer.Signed-off-by: Mikulas Patocka
Signed-off-by: Mike Snitzer -
Change the functions get_exception, read_exception and insert_exceptions
so that ps->area is passed as an argument.This patch doesn't change any functionality, but it refactors the code
to allow for a cleaner switch over to using dm-bufio.Signed-off-by: Mikulas Patocka
Signed-off-by: Mike Snitzer
07 Jan, 2014
1 commit
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In case CONFIG_DEBUG_OBJECTS_WORK is defined, it is needed to
call destroy_work_on_stack() which frees the debug object to pair
with INIT_WORK_ONSTACK().Signed-off-by: Liu, Chuansheng
Signed-off-by: Mike Snitzer
16 Oct, 2013
1 commit
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This patch fixes a particular type of data corruption that has been
encountered when loading a snapshot's metadata from disk.When we allocate a new chunk in persistent_prepare, we increment
ps->next_free and we make sure that it doesn't point to a metadata area
by further incrementing it if necessary.When we load metadata from disk on device activation, ps->next_free is
positioned after the last used data chunk. However, if this last used
data chunk is followed by a metadata area, ps->next_free is positioned
erroneously to the metadata area. A newly-allocated chunk is placed at
the same location as the metadata area, resulting in data or metadata
corruption.This patch changes the code so that ps->next_free skips the metadata
area when metadata are loaded in function read_exceptions.The patch also moves a piece of code from persistent_prepare_exception
to a separate function skip_metadata to avoid code duplication.CVE-2013-4299
Signed-off-by: Mikulas Patocka
Cc: stable@vger.kernel.org
Cc: Mike Snitzer
Signed-off-by: Alasdair G Kergon
20 Sep, 2013
1 commit
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The kernel reports a lockdep warning if a snapshot is invalidated because
it runs out of space.The lockdep warning was triggered by commit 0976dfc1d0cd80a4e9dfaf87bd87
("workqueue: Catch more locking problems with flush_work()") in v3.5.The warning is false positive. The real cause for the warning is that
the lockdep engine treats different instances of md->lock as a single
lock.This patch is a workaround - we use flush_workqueue instead of flush_work.
This code path is not performance sensitive (it is called only on
initialization or invalidation), thus it doesn't matter that we flush the
whole workqueue.The real fix for the problem would be to teach the lockdep engine to treat
different instances of md->lock as separate locks.Signed-off-by: Mikulas Patocka
Acked-by: Alasdair G Kergon
Signed-off-by: Mike Snitzer
Cc: stable@vger.kernel.org # 3.5+
01 Nov, 2011
1 commit
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These files were getting the defines for EXPORT_SYMBOL because
device.h was including module.h. But we are going to put an
end to that. So add the proper export.h include now.Signed-off-by: Paul Gortmaker
02 Aug, 2011
4 commits
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Coding style cleanups.
Signed-off-by: Alasdair G Kergon
Signed-off-by: Jonathan Brassow -
Use vzalloc() instead of vmalloc()+memset().
Signed-off-by: Joe Perches
Signed-off-by: Alasdair G Kergon -
Suppress sparse warnings about cpu_to_le32() by using __le32 types for
on-disk data etc.Signed-off-by: Alasdair G Kergon
-
This patch makes dm-snapshot flush disk cache when writing metadata for
merging snapshot.Without cache flushing the disk may reorder metadata write and other
data writes and there is a possibility of data corruption in case of
power fault.Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka
Signed-off-by: Alasdair G Kergon
29 May, 2011
1 commit
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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
Signed-off-by: Alasdair G Kergon
14 Jan, 2011
2 commits
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metadata_wq serves on-stack work items from chunk_io(). Even if
multiple chunk_io() are simultaneously in progress, each is
independent and queued only once, so multithreaded workqueue can be
safely used.Switch metadata_wq to multithread and flush the work item instead of
the workqueue in chunk_io().Signed-off-by: Tejun Heo
Signed-off-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon -
Convert all create[_singlethread]_work() users to the new
alloc[_ordered]_workqueue(). This conversion is mechanical and
doesn't introduce any behavior change.Signed-off-by: Tejun Heo
Signed-off-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon
27 Oct, 2010
1 commit
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Silly though it is, completions and wait_queue_heads use foo_ONSTACK
(COMPLETION_INITIALIZER_ONSTACK, DECLARE_COMPLETION_ONSTACK,
__WAIT_QUEUE_HEAD_INIT_ONSTACK and DECLARE_WAIT_QUEUE_HEAD_ONSTACK) so I
guess workqueues should do the same thing.s/INIT_WORK_ON_STACK/INIT_WORK_ONSTACK/
s/INIT_DELAYED_WORK_ON_STACK/INIT_DELAYED_WORK_ONSTACK/Cc: Peter Zijlstra
Acked-by: Tejun Heo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 Sep, 2010
1 commit
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This patch converts bio-based dm to support REQ_FLUSH/FUA instead of
now deprecated REQ_HARDBARRIER.* -EOPNOTSUPP handling logic dropped.
* Preflush is handled as before but postflush is dropped and replaced
with passing down REQ_FUA to member request_queues. This replaces
one array wide cache flush w/ member specific FUA writes.* __split_and_process_bio() now calls __clone_and_map_flush() directly
for flushes and guarantees all FLUSH bio's going to targets are zero
` length.* It's now guaranteed that all FLUSH bio's which are passed onto dm
targets are zero length. bio_empty_barrier() tests are replaced
with REQ_FLUSH tests.* Empty WRITE_BARRIERs are replaced with WRITE_FLUSHes.
* Dropped unlikely() around REQ_FLUSH tests. Flushes are not unlikely
enough to be marked with unlikely().* Block layer now filters out REQ_FLUSH/FUA bio's if the request_queue
doesn't support cache flushing. Advertise REQ_FLUSH | REQ_FUA
capability.* Request based dm isn't converted yet. dm_init_request_based_queue()
resets flush support to 0 for now. To avoid disturbing request
based dm code, dm->flush_error is added for bio based dm while
requested based dm continues to use dm->barrier_error.Lightly tested linear, stripe, raid1, snap and crypt targets. Please
proceed with caution as I'm not familiar with the code base.Signed-off-by: Tejun Heo
Cc: dm-devel@redhat.com
Cc: Christoph Hellwig
Signed-off-by: Jens Axboe
12 Aug, 2010
1 commit
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This patch fixes hard-coded value for the size of a chunk that includes
disk header for persistent snapshot. It should be changed to existing
macro NUM_SNAPSHOT_HDR_CHUNKS instead of using hard-coded value 1.Signed-off-by: Tomohiro Kusumi
Signed-off-by: Mikulas Patocka
Signed-off-by: Alasdair G Kergon
17 Feb, 2010
1 commit
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chunk_io() declares its 'struct mdata_req' on the stack and then
initializes its 'struct work_struct' member. Annotate the
initialization of this workqueue with INIT_WORK_ON_STACK to suppress a
debugobjects warning seen when CONFIG_DEBUG_OBJECTS_WORK is enabled.Signed-off-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon
11 Dec, 2009
5 commits
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Add functions that decide how many consecutive chunks of snapshot to
merge back into the origin next and to update the metadata afterwards.prepare_merge provides a pointer to the most recent still-to-be-merged
chunk and returns how many previous ones are consecutive and can be
processed together.commit_merge removes the nr_merged most-recent chunks permanently from
the exception store. The number must not exceed that returned by
prepare_merge.Introduce NUM_SNAPSHOT_HDR_CHUNKS to show where the snapshot header
chunk is accounted for.Signed-off-by: Mikulas Patocka
Reviewed-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon -
Store the reference to the snapshot cow device in the core snapshot
code instead of each exception store. It can be accessed through the
new function dm_snap_cow(). Exception stores should each now maintain a
reference to their parent snapshot struct.This is cleaner and makes part of the forthcoming snapshot merge code simpler.
Signed-off-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon
Reviewed-by: Jonathan Brassow
Cc: Mikulas Patocka -
Add number of sectors used by metadata to the end of the snapshot's status
line.Renamed dm_exception_store_type's 'fraction_full' to 'usage'. Renamed
arguments to be clearer about what is being returned. Also added
'metadata_sectors'.Signed-off-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon -
The exception structure is not necessarily just a snapshot
element (especially after we pull it out of dm-snap.c).Renaming appropriately.
Signed-off-by: Jonathan Brassow
Reviewed-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon -
Minor code touch-up. We don't need the 'else'.
Signed-off-by: Jonathan Brassow
Reviewed-by: Mikulas Patocka
Reviewed-by: Mike Snitzer
Signed-off-by: Alasdair G Kergon