Variables start_idx and end_idx are supposed to hold a page index
derived from the file offsets. The int type is not the right one though,
offsets larger than 1 << 44 will get silently trimmed off the high bits.
(1 << 44 is 16TiB)
What can go wrong, if start is below the boundary and end gets trimmed:
- if there's a page after start, we'll find it (radix_tree_gang_lookup_slot)
- the final check "if (page->index <= end_idx)" will unexpectedly fail
The function will return false, ie. "there's no page in the range",
although there is at least one.
btrfs_page_exists_in_range is used to prevent races in:
* in hole punching, where we make sure there are not pages in the
truncated range, otherwise we'll wait for them to finish and redo
truncation, but we're going to replace the pages with holes anyway so
the only problem is the intermediate state
* lock_extent_direct: we want to make sure there are no pages before we
lock and start DIO, to prevent stale data reads
For practical occurence of the bug, there are several constaints. The
file must be quite large, the affected range must cross the 16TiB
boundary and the internal state of the file pages and pending operations
must match. Also, we must not have started any ordered data in the
range, otherwise we don't even reach the buggy function check.
DIO locking tries hard in several places to avoid deadlocks with
buffered IO and avoids waiting for ranges. The worst consequence seems
to be stale data read.
CC: Liu Bo <bo.li.liu@oracle.com>
CC: stable@vger.kernel.org # 3.16+
Fixes: fc4adbff82 ("btrfs: Drop EXTENT_UPTODATE check in hole punching and direct locking")
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The setting of return code ret should be based on the error code
passed into function end_extent_writepage and not on ret. Thanks
to Liu Bo for spotting this mistake in the original fix I submitted.
Detected by CoverityScan, CID#1414312 ("Logically dead code")
Fixes: 5dca6eea91 ("Btrfs: mark mapping with error flag to report errors to userspace")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit b685d3d65a "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.
CC: David Sterba <dsterba@suse.com>
CC: linux-btrfs@vger.kernel.org
Fixes: b685d3d65a
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
Cycle mount btrfs can cause fiemap to return different result.
Like:
# mount /dev/vdb5 /mnt/btrfs
# dd if=/dev/zero bs=16K count=4 oflag=dsync of=/mnt/btrfs/file
# xfs_io -c "fiemap -v" /mnt/btrfs/file
/mnt/test/file:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..127]: 25088..25215 128 0x1
# umount /mnt/btrfs
# mount /dev/vdb5 /mnt/btrfs
# xfs_io -c "fiemap -v" /mnt/btrfs/file
/mnt/test/file:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..31]: 25088..25119 32 0x0
1: [32..63]: 25120..25151 32 0x0
2: [64..95]: 25152..25183 32 0x0
3: [96..127]: 25184..25215 32 0x1
But after above fiemap, we get correct merged result if we call fiemap
again.
# xfs_io -c "fiemap -v" /mnt/btrfs/file
/mnt/test/file:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..127]: 25088..25215 128 0x1
[REASON]
Btrfs will try to merge extent map when inserting new extent map.
btrfs_fiemap(start=0 len=(u64)-1)
|- extent_fiemap(start=0 len=(u64)-1)
|- get_extent_skip_holes(start=0 len=64k)
| |- btrfs_get_extent_fiemap(start=0 len=64k)
| |- btrfs_get_extent(start=0 len=64k)
| | Found on-disk (ino, EXTENT_DATA, 0)
| |- add_extent_mapping()
| |- Return (em->start=0, len=16k)
|
|- fiemap_fill_next_extent(logic=0 phys=X len=16k)
|
|- get_extent_skip_holes(start=0 len=64k)
| |- btrfs_get_extent_fiemap(start=0 len=64k)
| |- btrfs_get_extent(start=16k len=48k)
| | Found on-disk (ino, EXTENT_DATA, 16k)
| |- add_extent_mapping()
| | |- try_merge_map()
| | Merge with previous em start=0 len=16k
| | resulting em start=0 len=32k
| |- Return (em->start=0, len=32K) << Merged result
|- Stripe off the unrelated range (0~16K) of return em
|- fiemap_fill_next_extent(logic=16K phys=X+16K len=16K)
^^^ Causing split fiemap extent.
And since in add_extent_mapping(), em is already merged, in next
fiemap() call, we will get merged result.
[FIX]
Here we introduce a new structure, fiemap_cache, which records previous
fiemap extent.
And will always try to merge current fiemap_cache result before calling
fiemap_fill_next_extent().
Only when we failed to merge current fiemap extent with cached one, we
will call fiemap_fill_next_extent() to submit cached one.
So by this method, we can merge all fiemap extents.
It can also be done in fs/ioctl.c, however the problem is if
fieinfo->fi_extents_max == 0, we have no space to cache previous fiemap
extent.
So I choose to merge it in btrfs.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs updates from Chris Mason:
"This has fixes and cleanups Dave Sterba collected for the merge
window.
The biggest functional fixes are between btrfs raid5/6 and scrub, and
raid5/6 and device replacement. Some of our pending qgroup fixes are
included as well while I bash on the rest in testing.
We also have the usual set of cleanups, including one that makes
__btrfs_map_block() much more maintainable, and conversions from
atomic_t to refcount_t"
* 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (71 commits)
btrfs: fix the gfp_mask for the reada_zones radix tree
Btrfs: fix reported number of inode blocks
Btrfs: send, fix file hole not being preserved due to inline extent
Btrfs: fix extent map leak during fallocate error path
Btrfs: fix incorrect space accounting after failure to insert inline extent
Btrfs: fix invalid attempt to free reserved space on failure to cow range
btrfs: Handle delalloc error correctly to avoid ordered extent hang
btrfs: Fix metadata underflow caused by btrfs_reloc_clone_csum error
btrfs: check if the device is flush capable
btrfs: delete unused member nobarriers
btrfs: scrub: Fix RAID56 recovery race condition
btrfs: scrub: Introduce full stripe lock for RAID56
btrfs: Use ktime_get_real_ts for root ctime
Btrfs: handle only applicable errors returned by btrfs_get_extent
btrfs: qgroup: Fix qgroup corruption caused by inode_cache mount option
btrfs: use q which is already obtained from bdev_get_queue
Btrfs: switch to div64_u64 if with a u64 divisor
Btrfs: update scrub_parity to use u64 stripe_len
Btrfs: enable repair during read for raid56 profile
btrfs: use clear_page where appropriate
...
__vmalloc* allows users to provide gfp flags for the underlying
allocation. This API is quite popular
$ git grep "=[[:space:]]__vmalloc\|return[[:space:]]*__vmalloc" | wc -l
77
The only problem is that many people are not aware that they really want
to give __GFP_HIGHMEM along with other flags because there is really no
reason to consume precious lowmemory on CONFIG_HIGHMEM systems for pages
which are mapped to the kernel vmalloc space. About half of users don't
use this flag, though. This signals that we make the API unnecessarily
too complex.
This patch simply uses __GFP_HIGHMEM implicitly when allocating pages to
be mapped to the vmalloc space. Current users which add __GFP_HIGHMEM
are simplified and drop the flag.
Link: http://lkml.kernel.org/r/20170307141020.29107-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Cristopher Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are many code paths opencoding kvmalloc. Let's use the helper
instead. The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator. E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation. This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously. There is no guarantee something like that happens
though.
This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.
Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Santosh Raspatur <santosh@chelsio.com>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Yishai Hadas <yishaih@mellanox.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commits cc8385b59e and 7ef70b4d99 added preallocation for the
reada radix trees and also switched them over to GFP_KERNEL for the
default gfp mask.
Since we're doing radix tree insertions under spinlocks, we need
to make sure the mask doesn't allow sleeping. This fix keeps
the radix preallocation but switches back to the original gfp_mask.
Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull block layer updates from Jens Axboe:
- Add BFQ IO scheduler under the new blk-mq scheduling framework. BFQ
was initially a fork of CFQ, but subsequently changed to implement
fairness based on B-WF2Q+, a modified variant of WF2Q. BFQ is meant
to be used on desktop type single drives, providing good fairness.
From Paolo.
- Add Kyber IO scheduler. This is a full multiqueue aware scheduler,
using a scalable token based algorithm that throttles IO based on
live completion IO stats, similary to blk-wbt. From Omar.
- A series from Jan, moving users to separately allocated backing
devices. This continues the work of separating backing device life
times, solving various problems with hot removal.
- A series of updates for lightnvm, mostly from Javier. Includes a
'pblk' target that exposes an open channel SSD as a physical block
device.
- A series of fixes and improvements for nbd from Josef.
- A series from Omar, removing queue sharing between devices on mostly
legacy drivers. This helps us clean up other bits, if we know that a
queue only has a single device backing. This has been overdue for
more than a decade.
- Fixes for the blk-stats, and improvements to unify the stats and user
windows. This both improves blk-wbt, and enables other users to
register a need to receive IO stats for a device. From Omar.
- blk-throttle improvements from Shaohua. This provides a scalable
framework for implementing scalable priotization - particularly for
blk-mq, but applicable to any type of block device. The interface is
marked experimental for now.
- Bucketized IO stats for IO polling from Stephen Bates. This improves
efficiency of polled workloads in the presence of mixed block size
IO.
- A few fixes for opal, from Scott.
- A few pulls for NVMe, including a lot of fixes for NVMe-over-fabrics.
From a variety of folks, mostly Sagi and James Smart.
- A series from Bart, improving our exposed info and capabilities from
the blk-mq debugfs support.
- A series from Christoph, cleaning up how handle WRITE_ZEROES.
- A series from Christoph, cleaning up the block layer handling of how
we track errors in a request. On top of being a nice cleanup, it also
shrinks the size of struct request a bit.
- Removal of mg_disk and hd (sorry Linus) by Christoph. The former was
never used by platforms, and the latter has outlived it's usefulness.
- Various little bug fixes and cleanups from a wide variety of folks.
* 'for-4.12/block' of git://git.kernel.dk/linux-block: (329 commits)
block: hide badblocks attribute by default
blk-mq: unify hctx delay_work and run_work
block: add kblock_mod_delayed_work_on()
blk-mq: unify hctx delayed_run_work and run_work
nbd: fix use after free on module unload
MAINTAINERS: bfq: Add Paolo as maintainer for the BFQ I/O scheduler
blk-mq-sched: alloate reserved tags out of normal pool
mtip32xx: use runtime tag to initialize command header
scsi: Implement blk_mq_ops.show_rq()
blk-mq: Add blk_mq_ops.show_rq()
blk-mq: Show operation, cmd_flags and rq_flags names
blk-mq: Make blk_flags_show() callers append a newline character
blk-mq: Move the "state" debugfs attribute one level down
blk-mq: Unregister debugfs attributes earlier
blk-mq: Only unregister hctxs for which registration succeeded
blk-mq-debugfs: Rename functions for registering and unregistering the mq directory
blk-mq: Let blk_mq_debugfs_register() look up the queue name
blk-mq: Register <dev>/queue/mq after having registered <dev>/queue
ide-pm: always pass 0 error to ide_complete_rq in ide_do_devset
ide-pm: always pass 0 error to __blk_end_request_all
..
Pull btrfs fix from Chris Mason:
"We have one more fix for btrfs.
This gets rid of a new WARN_ON from rc1 that ended up making more
noise than we really want. The larger fix for the underflow got
delayed a bit and it's better for now to put it under
CONFIG_BTRFS_DEBUG"
* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: qgroup: move noisy underflow warning to debugging build
Currently when there are buffered writes that were not yet flushed and
they fall within allocated ranges of the file (that is, not in holes or
beyond eof assuming there are no prealloc extents beyond eof), btrfs
simply reports an incorrect number of used blocks through the stat(2)
system call (or any of its variants), regardless of mount options or
inode flags (compress, compress-force, nodatacow). This is because the
number of blocks used that is reported is based on the current number
of bytes in the vfs inode plus the number of dealloc bytes in the btrfs
inode. The later covers bytes that both fall within allocated regions
of the file and holes.
Example scenarios where the number of reported blocks is wrong while the
buffered writes are not flushed:
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt/sdc
$ xfs_io -f -c "pwrite -S 0xaa 0 64K" /mnt/sdc/foo1
wrote 65536/65536 bytes at offset 0
64 KiB, 16 ops; 0.0000 sec (259.336 MiB/sec and 66390.0415 ops/sec)
$ sync
$ xfs_io -c "pwrite -S 0xbb 0 64K" /mnt/sdc/foo1
wrote 65536/65536 bytes at offset 0
64 KiB, 16 ops; 0.0000 sec (192.308 MiB/sec and 49230.7692 ops/sec)
# The following should have reported 64K...
$ du -h /mnt/sdc/foo1
128K /mnt/sdc/foo1
$ sync
# After flushing the buffered write, it now reports the correct value.
$ du -h /mnt/sdc/foo1
64K /mnt/sdc/foo1
$ xfs_io -f -c "falloc -k 0 128K" -c "pwrite -S 0xaa 0 64K" /mnt/sdc/foo2
wrote 65536/65536 bytes at offset 0
64 KiB, 16 ops; 0.0000 sec (520.833 MiB/sec and 133333.3333 ops/sec)
$ sync
$ xfs_io -c "pwrite -S 0xbb 64K 64K" /mnt/sdc/foo2
wrote 65536/65536 bytes at offset 65536
64 KiB, 16 ops; 0.0000 sec (260.417 MiB/sec and 66666.6667 ops/sec)
# The following should have reported 128K...
$ du -h /mnt/sdc/foo2
192K /mnt/sdc/foo2
$ sync
# After flushing the buffered write, it now reports the correct value.
$ du -h /mnt/sdc/foo2
128K /mnt/sdc/foo2
So the number of used file blocks is simply incorrect, unlike in other
filesystems such as ext4 and xfs for example, but only while the buffered
writes are not flushed.
Fix this by tracking the number of delalloc bytes that fall within holes
and beyond eof of a file, and use instead this new counter when reporting
the number of used blocks for an inode.
Another different problem that exists is that the delalloc bytes counter
is reset when writeback starts (by clearing the EXTENT_DEALLOC flag from
the respective range in the inode's iotree) and the vfs inode's bytes
counter is only incremented when writeback finishes (through
insert_reserved_file_extent()). Therefore while writeback is ongoing we
simply report a wrong number of blocks used by an inode if the write
operation covers a range previously unallocated. While this change does
not fix this problem, it does minimizes it a lot by shortening that time
window, as the new dealloc bytes counter (new_delalloc_bytes) is only
decremented when writeback finishes right before updating the vfs inode's
bytes counter. Fully fixing this second problem is not trivial and will
be addressed later by a different patch.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Normally we don't have inline extents followed by regular extents, but
there's currently at least one harmless case where this happens. For
example, when the page size is 4Kb and compression is enabled:
$ mkfs.btrfs -f /dev/sdb
$ mount -o compress /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0xaa 0 4K" -c "fsync" /mnt/foobar
$ xfs_io -c "pwrite -S 0xbb 8K 4K" -c "fsync" /mnt/foobar
In this case we get a compressed inline extent, representing 4Kb of
data, followed by a hole extent and then a regular data extent. The
inline extent was not expanded/converted to a regular extent exactly
because it represents 4Kb of data. This does not cause any apparent
problem (such as the issue solved by commit e1699d2d7b
("btrfs: add missing memset while reading compressed inline extents"))
except trigger an unexpected case in the incremental send code path
that makes us issue an operation to write a hole when it's not needed,
resulting in more writes at the receiver and wasting space at the
receiver.
So teach the incremental send code to deal with this particular case.
The issue can be currently triggered by running fstests btrfs/137 with
compression enabled (MOUNT_OPTIONS="-o compress" ./check btrfs/137).
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
If the call to btrfs_qgroup_reserve_data() failed, we were leaking an
extent map structure. The failure can happen either due to an -ENOMEM
condition or, when quotas are enabled, due to -EDQUOT for example.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[BUG]
If run_delalloc_range() returns error and there is already some ordered
extents created, btrfs will be hanged with the following backtrace:
Call Trace:
__schedule+0x2d4/0xae0
schedule+0x3d/0x90
btrfs_start_ordered_extent+0x160/0x200 [btrfs]
? wake_atomic_t_function+0x60/0x60
btrfs_run_ordered_extent_work+0x25/0x40 [btrfs]
btrfs_scrubparity_helper+0x1c1/0x620 [btrfs]
btrfs_flush_delalloc_helper+0xe/0x10 [btrfs]
process_one_work+0x2af/0x720
? process_one_work+0x22b/0x720
worker_thread+0x4b/0x4f0
kthread+0x10f/0x150
? process_one_work+0x720/0x720
? kthread_create_on_node+0x40/0x40
ret_from_fork+0x2e/0x40
[CAUSE]
|<------------------ delalloc range --------------------------->|
| OE 1 | OE 2 | ... | OE n |
|<>| |<---------- cleanup range --------->|
||
\_=> First page handled by end_extent_writepage() in __extent_writepage()
The problem is caused by error handler of run_delalloc_range(), which
doesn't handle any created ordered extents, leaving them waiting on
btrfs_finish_ordered_io() to finish.
However after run_delalloc_range() returns error, __extent_writepage()
won't submit bio, so btrfs_writepage_end_io_hook() won't be triggered
except the first page, and btrfs_finish_ordered_io() won't be triggered
for created ordered extents either.
So OE 2~n will hang forever, and if OE 1 is larger than one page, it
will also hang.
[FIX]
Introduce btrfs_cleanup_ordered_extents() function to cleanup created
ordered extents and finish them manually.
The function is based on existing
btrfs_endio_direct_write_update_ordered() function, and modify it to
act just like btrfs_writepage_endio_hook() but handles specified range
other than one page.
After fix, delalloc error will be handled like:
|<------------------ delalloc range --------------------------->|
| OE 1 | OE 2 | ... | OE n |
|<>|<-------- ----------->|<------ old error handler --------->|
|| ||
|| \_=> Cleaned up by cleanup_ordered_extents()
\_=> First page handled by end_extent_writepage() in __extent_writepage()
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
[BUG]
When btrfs_reloc_clone_csum() reports error, it can underflow metadata
and leads to kernel assertion on outstanding extents in
run_delalloc_nocow() and cow_file_range().
BTRFS info (device vdb5): relocating block group 12582912 flags data
BTRFS info (device vdb5): found 1 extents
assertion failed: inode->outstanding_extents >= num_extents, file: fs/btrfs//extent-tree.c, line: 5858
Currently, due to another bug blocking ordered extents, the bug is only
reproducible under certain block group layout and using error injection.
a) Create one data block group with one 4K extent in it.
To avoid the bug that hangs btrfs due to ordered extent which never
finishes
b) Make btrfs_reloc_clone_csum() always fail
c) Relocate that block group
[CAUSE]
run_delalloc_nocow() and cow_file_range() handles error from
btrfs_reloc_clone_csum() wrongly:
(The ascii chart shows a more generic case of this bug other than the
bug mentioned above)
|<------------------ delalloc range --------------------------->|
| OE 1 | OE 2 | ... | OE n |
|<----------- cleanup range --------------->|
|<----------- ----------->|
\/
btrfs_finish_ordered_io() range
So error handler, which calls extent_clear_unlock_delalloc() with
EXTENT_DELALLOC and EXTENT_DO_ACCOUNT bits, and btrfs_finish_ordered_io()
will both cover OE n, and free its metadata, causing metadata under flow.
[Fix]
The fix is to ensure after calling btrfs_add_ordered_extent(), we only
call error handler after increasing the iteration offset, so that
cleanup range won't cover any created ordered extent.
|<------------------ delalloc range --------------------------->|
| OE 1 | OE 2 | ... | OE n |
|<----------- ----------->|<---------- cleanup range --------->|
\/
btrfs_finish_ordered_io() range
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Allocate struct backing_dev_info separately instead of embedding it
inside superblock. This unifies handling of bdi among users.
CC: Chris Mason <clm@fb.com>
CC: Josef Bacik <jbacik@fb.com>
CC: David Sterba <dsterba@suse.com>
CC: linux-btrfs@vger.kernel.org
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
The WARN_ON and warning from report_reserved_underflow can become very
noisy and is visible unconditionally although this is namely for
debugging. The patch "btrfs: Add WARN_ON for qgroup reserved underflow"
(18dc22c19b) went to 4.11-rc1 and the plan
was to get the fix as well, but this hasn't happened.
CC: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The block layer call chain from submit_bio will check if the write cache
is enabled for the given queue before submitting the flush. This will
add a code to fail fast if its not.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ updated changelog to reflect current code stat, blkdev_issue_flush is
not used yet ]
Signed-off-by: David Sterba <dsterba@suse.com>
The last consumer of nobarriers is removed by the commit [1] and sync
won't fail with EOPNOTSUPP anymore. Thus, now when write cache is write
through it just return success without actually transpiring such a
request to the block device/lun.
[1]
commit b25de9d6da
block: remove BIO_EOPNOTSUPP
And, as the device/lun write cache state may change dynamically saving
such as state won't help either. So deleting the member nobarriers.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When scrubbing a RAID5 which has recoverable data corruption (only one
data stripe is corrupted), sometimes scrub will report more csum errors
than expected. Sometimes even unrecoverable error will be reported.
The problem can be easily reproduced by the following steps:
1) Create a btrfs with RAID5 data profile with 3 devs
2) Mount it with nospace_cache or space_cache=v2
To avoid extra data space usage.
3) Create a 128K file and sync the fs, unmount it
Now the 128K file lies at the beginning of the data chunk
4) Locate the physical bytenr of data chunk on dev3
Dev3 is the 1st data stripe.
5) Corrupt the first 64K of the data chunk stripe on dev3
6) Mount the fs and scrub it
The correct csum error number should be 16 (assuming using x86_64).
Larger csum error number can be reported in a 1/3 chance.
And unrecoverable error can also be reported in a 1/10 chance.
The root cause of the problem is RAID5/6 recover code has race
condition, due to the fact that full scrub is initiated per device.
While for other mirror based profiles, each mirror is independent with
each other, so race won't cause any big problem.
For example:
Corrupted | Correct | Correct |
| Scrub dev3 (D1) | Scrub dev2 (D2) | Scrub dev1(P) |
------------------------------------------------------------------------
Read out D1 |Read out D2 |Read full stripe |
Check csum |Check csum |Check parity |
Csum mismatch |Csum match, continue |Parity mismatch |
handle_errored_block | |handle_errored_block |
Read out full stripe | | Read out full stripe|
D1 csum error(err++) | | D1 csum error(err++)|
Recover D1 | | Recover D1 |
So D1's csum error is accounted twice, just because
handle_errored_block() doesn't have enough protection, and race can happen.
On even worse case, for example D1's recovery code is re-writing
D1/D2/P, and P's recovery code is just reading out full stripe, then we
can cause unrecoverable error.
This patch will use previously introduced lock_full_stripe() and
unlock_full_stripe() to protect the whole scrub_handle_errored_block()
function for RAID56 recovery.
So no extra csum error nor unrecoverable error.
Reported-by: Goffredo Baroncelli <kreijack@libero.it>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unlike mirror based profiles, RAID5/6 recovery needs to read out the
whole full stripe.
And if we don't do proper protection, it can easily cause race condition.
Introduce 2 new functions: lock_full_stripe() and unlock_full_stripe()
for RAID5/6.
Which store a rb_tree of mutexes for full stripes, so scrub callers can
use them to lock a full stripe to avoid race.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_root_item maintains the ctime for root updates. This is not part
of vfs_inode.
Since current_time() uses struct inode* as an argument as Linus
suggested, this cannot be used to update root times unless, we modify
the signature to use inode.
Since btrfs uses nanosecond time granularity, it can also use
ktime_get_real_ts directly to obtain timestamp for the root. It is
necessary to use the timespec time api here because the same
btrfs_set_stack_timespec_*() apis are used for vfs inode times as well.
These can be transitioned to using timespec64 when btrfs internally
changes to use timespec64 as well.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_get_extent() never returns NULL pointers, so this code introduces
a static checker warning.
The btrfs_get_extent() is a bit complex, but trust me that it doesn't
return NULLs and also if it did we would trigger the BUG_ON(!em) before
the last return statement.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[ updated subject ]
Signed-off-by: David Sterba <dsterba@suse.com>
[BUG]
The easist way to reproduce the bug is:
------
# mkfs.btrfs -f $dev -n 16K
# mount $dev $mnt -o inode_cache
# btrfs quota enable $mnt
# btrfs quota rescan -w $mnt
# btrfs qgroup show $mnt
qgroupid rfer excl
-------- ---- ----
0/5 32.00KiB 32.00KiB
^^ Twice the correct value
------
And fstests/btrfs qgroup test group can easily detect them with
inode_cache mount option.
Although some of them are false alerts since old test cases are using
fixed golden output.
While new test cases will use "btrfs check" to detect qgroup mismatch.
[CAUSE]
Inode_cache mount option will make commit_fs_roots() to call
btrfs_save_ino_cache() to update fs/subvol trees, and generate new
delayed refs.
However we call btrfs_qgroup_prepare_account_extents() too early, before
commit_fs_roots().
This makes the "old_roots" for newly generated extents are always NULL.
For freeing extent case, this makes both new_roots and old_roots to be
empty, while correct old_roots should not be empty.
This causing qgroup numbers not decreased correctly.
[FIX]
Modify the timing of calling btrfs_qgroup_prepare_account_extents() to
just before btrfs_qgroup_account_extents(), and add needed delayed_refs
handler.
So qgroup can handle inode_map mount options correctly.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have already assigned q from bdev_get_queue() so use it.
And rearrange the code for better view.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is fixing code pieces where we use div_u64 when passing a u64 divisor.
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 3d8da67817 ("Btrfs: fix divide error upon chunk's stripe_len")
changed stripe_len in struct map_lookup to u64, but didn't update
stripe_len in struct scrub_parity.
This updates the type and switches to div64_u64_rem to match u64 divisor.
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Now that scrub can fix data errors with the help of parity for raid56
profile, repair during read is able to as well.
Although the mirror num in raid56 scenario has different meanings, i.e.
0 or 1: read data directly
> 1: do recover with parity,
it could be fit into how we repair bad block during read.
The trick is to use BTRFS_MAP_READ instead of BTRFS_MAP_WRITE to get the
device and position on it.
Cc: David Sterba <dsterba@suse.cz>
Tested-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There's a helper to clear whole page, with a arch-specific optimized
code. The replaced cases do not seem to be in performace critical code,
but we still might get some percent gain.
Signed-off-by: David Sterba <dsterba@suse.com>
scrub_setup_recheck_block() calls btrfs_map_sblock() and then accesses
bbio without protection of bio_counter.
This can lead to use-after-free if racing with dev replace cancel.
Fix it by increasing bio_counter before calling btrfs_map_sblock() and
decreasing the bio_counter when corresponding recover is finished.
Cc: Liu Bo <bo.li.liu@oracle.com>
Reported-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When raid56 dev-replace is cancelled by running scrub, we will free
target device without waiting for in-flight bios, causing the following
NULL pointer deference or general protection failure.
BUG: unable to handle kernel NULL pointer dereference at 00000000000005e0
IP: generic_make_request_checks+0x4d/0x610
CPU: 1 PID: 11676 Comm: kworker/u4:14 Tainted: G O 4.11.0-rc2 #72
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
Workqueue: btrfs-endio-raid56 btrfs_endio_raid56_helper [btrfs]
task: ffff88002875b4c0 task.stack: ffffc90001334000
RIP: 0010:generic_make_request_checks+0x4d/0x610
Call Trace:
? generic_make_request+0xc7/0x360
generic_make_request+0x24/0x360
? generic_make_request+0xc7/0x360
submit_bio+0x64/0x120
? page_in_rbio+0x4d/0x80 [btrfs]
? rbio_orig_end_io+0x80/0x80 [btrfs]
finish_rmw+0x3f4/0x540 [btrfs]
validate_rbio_for_rmw+0x36/0x40 [btrfs]
raid_rmw_end_io+0x7a/0x90 [btrfs]
bio_endio+0x56/0x60
end_workqueue_fn+0x3c/0x40 [btrfs]
btrfs_scrubparity_helper+0xef/0x620 [btrfs]
btrfs_endio_raid56_helper+0xe/0x10 [btrfs]
process_one_work+0x2af/0x720
? process_one_work+0x22b/0x720
worker_thread+0x4b/0x4f0
kthread+0x10f/0x150
? process_one_work+0x720/0x720
? kthread_create_on_node+0x40/0x40
ret_from_fork+0x2e/0x40
RIP: generic_make_request_checks+0x4d/0x610 RSP: ffffc90001337bb8
In btrfs_dev_replace_finishing(), we will call
btrfs_rm_dev_replace_blocked() to wait bios before destroying the target
device when scrub is finished normally.
However when dev-replace is aborted, either due to error or cancelled by
scrub, we didn't wait for bios, this can lead to use-after-free if there
are bios holding the target device.
Furthermore, for raid56 scrub, at least 2 places are calling
btrfs_map_sblock() without protection of bio_counter, leading to the
problem.
This patch fixes the problem:
1) Wait for bio_counter before freeing target device when canceling
replace
2) When calling btrfs_map_sblock() for raid56, use bio_counter to
protect the call.
Cc: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In the following situation, scrub will calculate wrong parity to
overwrite the correct one:
RAID5 full stripe:
Before
| Dev 1 | Dev 2 | Dev 3 |
| Data stripe 1 | Data stripe 2 | Parity Stripe |
--------------------------------------------------- 0
| 0x0000 (Bad) | 0xcdcd | 0x0000 |
--------------------------------------------------- 4K
| 0xcdcd | 0xcdcd | 0x0000 |
...
| 0xcdcd | 0xcdcd | 0x0000 |
--------------------------------------------------- 64K
After scrubbing dev3 only:
| Dev 1 | Dev 2 | Dev 3 |
| Data stripe 1 | Data stripe 2 | Parity Stripe |
--------------------------------------------------- 0
| 0xcdcd (Good) | 0xcdcd | 0xcdcd (Bad) |
--------------------------------------------------- 4K
| 0xcdcd | 0xcdcd | 0x0000 |
...
| 0xcdcd | 0xcdcd | 0x0000 |
--------------------------------------------------- 64K
The reason is that after raid56 read rebuild rbio->stripe_pages are all
correctly recovered (0xcd for data stripes).
However when we check and repair parity in
scrub_parity_check_and_repair(), we will append pages in sparity->spages
list to rbio->bio_pages[], which contains old on-disk data.
And when we submit parity data to disk, we calculate parity using
rbio->bio_pages[] first, if rbio->bio_pages[] not found, then fallback
to rbio->stripe_pages[].
The patch fix it by not appending pages from sparity->spages.
So finish_parity_scrub() will use rbio->stripe_pages[] which is correct.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Newly introduced qgroup reserved space trace points are normally nested
into several common qgroup operations.
While some other trace points are not well placed to co-operate with
them, causing confusing output.
This patch re-arrange trace_btrfs_qgroup_release_data() and
trace_btrfs_qgroup_free_delayed_ref() trace points so they are triggered
before reserved space ones.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Introduce the following trace points:
qgroup_update_reserve
qgroup_meta_reserve
These trace points are handy to trace qgroup reserve space related
problems.
Also export btrfs_qgroup structure, as now we directly pass btrfs_qgroup
structure to trace points, so that structure needs to be exported.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
In raid56 scenario, after trying parity recovery, we didn't set
mirror_num for btrfs_bio with failed mirror_num, hence
end_bio_extent_readpage() will report a random mirror_num in dmesg
log.
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Scrub repairs data by the unit called scrub_block, which may contain
several pages. Scrub always tries to look up a good copy of a whole
block, but if there's no such copy, it tries to do repair page by page.
If we don't set page's io_error when checking this bad copy, in the last
step, we may skip this page when repairing bad copy from good copy.
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There are several operations, usually started from ioctls, that cannot
run concurrently. The status is tracked in
mutually_exclusive_operation_running as an atomic_t. We can easily track
the status as one of the per-filesystem flag bits with same
synchronization guarantees.
The conversion replaces:
* atomic_xchg(..., 1) -> test_and_set_bit(FLAG, ...)
* atomic_set(..., 0) -> clear_bit(FLAG, ...)
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We are facing the same problem with EDQUOT which was experienced with
ENOSPC. Not sure if we require a full ticketing system such as ENOSPC, but
here is a quick fix, which may be too big a hammer.
Quotas are reserved during the start of an operation, incrementing
qg->reserved. However, it is written to disk in a commit_transaction
which could take as long as commit_interval. In the meantime there
could be deletions which are not accounted for because deletions are
accounted for only while committed (free_refroot). So, when we get
a EDQUOT flush the data to disk and try again.
This fixes fstests btrfs/139.
Here is a sample script which shows this issue.
DEVICE=/dev/vdb
MOUNTPOINT=/mnt
TESTVOL=$MOUNTPOINT/tmp
QUOTA=5
PROG=btrfs
DD_BS="4k"
DD_COUNT="256"
RUN_TIMES=5000
mkfs.btrfs -f $DEVICE
mount -o commit=240 $DEVICE $MOUNTPOINT
$PROG subvolume create $TESTVOL
$PROG quota enable $TESTVOL
$PROG qgroup limit ${QUOTA}G $TESTVOL
typeset -i DD_RUN_GOOD
typeset -i QUOTA
function _check_cmd() {
if [[ ${?} > 0 ]]; then
echo -n "$(date) E: Running previous command"
echo ${*}
echo "Without sync"
$PROG qgroup show -pcreFf ${TESTVOL}
echo "With sync"
$PROG qgroup show -pcreFf --sync ${TESTVOL}
exit 1
fi
}
while true; do
DD_RUN_GOOD=$RUN_TIMES
while (( ${DD_RUN_GOOD} != 0 )); do
dd if=/dev/zero of=${TESTVOL}/quotatest${DD_RUN_GOOD} bs=${DD_BS} count=${DD_COUNT}
_check_cmd "dd if=/dev/zero of=${TESTVOL}/quotatest${DD_RUN_GOOD} bs=${DD_BS} count=${DD_COUNT}"
DD_RUN_GOOD=(${DD_RUN_GOOD}-1)
done
$PROG qgroup show -pcref $TESTVOL
echo "----------- Cleanup ---------- "
rm $TESTVOL/quotatest*
done
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Define the SEQ_LAST macro to replace (u64)-1 in places where said
value triggers a special-case ref search behavior.
Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Replace hardcoded numeric values for __merge_refs 'mode' argument
with descriptive constants.
Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The members have been effectively unused since "Btrfs: rework qgroup
accounting" (fcebe4562d), there's no substitute for
assert_qgroups_uptodate so it's removed as well.
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The name is misleading and the local variable serves no purpose.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We can preallocate the node so insertion does not have to do that under
the lock. The GFP flags for the global radix tree are initialized to
GFP_NOFS & ~__GFP_DIRECT_RECLAIM
but we can use GFP_KERNEL, because readahead is optional and not on any
critical writeout path.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We can preallocate the node so insertion does not have to do that under
the lock. The GFP flags for the per-device radix tree are initialized to
GFP_NOFS & ~__GFP_DIRECT_RECLAIM
but we can use GFP_KERNEL, same as an allocation above anyway, but also
because readahead is optional and not on any critical writeout path.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Code cleanup.
The code block is for !(*flags & MS_RDONLY). We don't need
to check it again.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We also don't bother to flush free space cache while with free space
tree.
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These two BUG_ON()s would never be true, ensured by callers' logic.
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This adds a helper to show directly whether ops require full stripe.
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
With this, we can avoid allocating memory for dev replace copies if the
target dev is not available.
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since this part is mostly independent, this moves it to a separate
function.
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
As the part of getting extra mirror in __btrfs_map_block is
independent, this puts it into a separate function.
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Since DISCARD is not as important as an operation like write, we don't
copy it to target device during replace, and it makes __btrfs_map_block
less complex.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We have similar code here and there, this merges them into a helper.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
While debugging truncate problems, I found that these tracepoints could
help us quickly know what went wrong.
Two sets of tracepoints are created to track regular/prealloc file item
and inline file item respectively, I put inline as a separate one since
what inline file items cares about are way less than the regular one.
This adds four tracepoints:
- btrfs_get_extent_show_fi_regular
- btrfs_get_extent_show_fi_inline
- btrfs_truncate_show_fi_regular
- btrfs_truncate_show_fi_inline
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ formatting adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After 76b42abbf7 ("Btrfs: fix data loss after truncate when using the
no-holes feature"),
For either NO_HOLES or inline extents, we've set last_size to newsize to
avoid data loss after remount or inode got evicted and read again, thus,
we don't need this check anymore.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
If your filesystem has, eg, data:raid0 metadata:raid1, and you run "btrfs
balance -dconvert=raid1", the meta.target field will be uninitialized.
That's otherwise ok, as it's unused except for this warning.
Thus, let's use the existing set of raid levels for the comparison.
As a side effect, non-convert balances will now nag about data>metadata.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from Chris Mason:
"Dave Sterba collected a few more fixes for the last rc.
These aren't marked for stable, but I'm putting them in with a batch
were testing/sending by hand for this release"
* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix potential use-after-free for cloned bio
Btrfs: fix segmentation fault when doing dio read
Btrfs: fix invalid dereference in btrfs_retry_endio
btrfs: drop the nossd flag when remounting with -o ssd
KASAN reports that there is a use-after-free case of bio in btrfs_map_bio.
If we need to submit IOs to several disks at a time, the original bio
would get cloned and mapped to the destination disk, but we really should
use the original bio instead of a cloned bio to do the sanity check
because cloned bios are likely to be freed by its endio.
Reported-by: Diego <diegocg@gmail.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 2dabb32484 ("Btrfs: Direct I/O read: Work on sectorsized blocks")
introduced this bug during iterating bio pages in dio read's endio hook,
and it could end up with segment fault of the dio reading task.
So the reason is 'if (nr_sectors--)', and it makes the code assume that
there is one more block in the same page, so page offset is increased and
the bio which is created to repair the bad block then has an incorrect
bvec.bv_offset, and a later access of the page content would throw a
segmentation fault.
This also adds ASSERT to check page offset against page size.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When doing directIO repair, we have this oops:
[ 1458.532816] general protection fault: 0000 [#1] SMP
...
[ 1458.536291] Workqueue: btrfs-endio-repair btrfs_endio_repair_helper [btrfs]
[ 1458.536893] task: ffff88082a42d100 task.stack: ffffc90002b3c000
[ 1458.537499] RIP: 0010:btrfs_retry_endio+0x7e/0x1a0 [btrfs]
...
[ 1458.543261] Call Trace:
[ 1458.543958] ? rcu_read_lock_sched_held+0xc4/0xd0
[ 1458.544374] bio_endio+0xed/0x100
[ 1458.544750] end_workqueue_fn+0x3c/0x40 [btrfs]
[ 1458.545257] normal_work_helper+0x9f/0x900 [btrfs]
[ 1458.545762] btrfs_endio_repair_helper+0x12/0x20 [btrfs]
[ 1458.546224] process_one_work+0x34d/0xb70
[ 1458.546570] ? process_one_work+0x29e/0xb70
[ 1458.546938] worker_thread+0x1cf/0x960
[ 1458.547263] ? process_one_work+0xb70/0xb70
[ 1458.547624] kthread+0x17d/0x180
[ 1458.547909] ? kthread_create_on_node+0x70/0x70
[ 1458.548300] ret_from_fork+0x31/0x40
It turns out that btrfs_retry_endio is trying to get inode from a directIO
page.
This fixes the problem by using the saved inode pointer, done->inode.
btrfs_retry_endio_nocsum has the same problem, and it's fixed as well.
Also cleanup unused @start (which is too trivial for a separate patch).
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The opposite case was already handled right in the very next switch entry.
And also when turning on nossd, drop ssd_spread.
Reported-by: Hans van Kranenburg <hans.van.kranenburg@mendix.com>
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from Chris Mason:
"We have three small fixes queued up in my for-linus-4.11 branch"
* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix an integer overflow check
btrfs: Change qgroup_meta_rsv to 64bit
Btrfs: bring back repair during read
This isn't super serious because you need CAP_ADMIN to run this code.
I added this integer overflow check last year but apparently I am
rubbish at writing integer overflow checks... There are two issues.
First, access_ok() works on unsigned long type and not u64 so on 32 bit
systems the access_ok() could be checking a truncated size. The other
issue is that we should be using a stricter limit so we don't overflow
the kzalloc() setting ctx->clone_roots later in the function after the
access_ok():
alloc_size = sizeof(struct clone_root) * (arg->clone_sources_count + 1);
sctx->clone_roots = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN);
Fixes: f5ecec3ce2 ("btrfs: send: silence an integer overflow warning")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ added comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
Using an int value is causing qg->reserved to become negative and
exclusive -EDQUOT to be reached prematurely.
This affects exclusive qgroups only.
TEST CASE:
DEVICE=/dev/vdb
MOUNTPOINT=/mnt
SUBVOL=$MOUNTPOINT/tmp
umount $SUBVOL
umount $MOUNTPOINT
mkfs.btrfs -f $DEVICE
mount /dev/vdb $MOUNTPOINT
btrfs quota enable $MOUNTPOINT
btrfs subvol create $SUBVOL
umount $MOUNTPOINT
mount /dev/vdb $MOUNTPOINT
mount -o subvol=tmp $DEVICE $SUBVOL
btrfs qgroup limit -e 3G $SUBVOL
btrfs quota rescan /mnt -w
for i in `seq 1 44000`; do
dd if=/dev/zero of=/mnt/tmp/test_$i bs=10k count=1
if [[ $? > 0 ]]; then
btrfs qgroup show -pcref $SUBVOL
exit 1
fi
done
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
[ add reproducer to changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 20a7db8ab3 ("btrfs: add dummy callback for readpage_io_failed
and drop checks") made a cleanup around readpage_io_failed_hook, and
it was supposed to keep the original sematics, but it also
unexpectedly disabled repair during read for dup, raid1 and raid10.
This fixes the problem by letting data's inode call the generic
readpage_io_failed callback by returning -EAGAIN from its
readpage_io_failed_hook in order to notify end_bio_extent_readpage to
do the rest. We don't call it directly because the generic one takes
an offset from end_bio_extent_readpage() to calculate the index in the
checksum array and inode's readpage_io_failed_hook doesn't offer that
offset.
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ keep the const function attribute ]
Signed-off-by: David Sterba <dsterba@suse.com>
Pull btrfs fixes from Chris Mason:
"Zygo tracked down a very old bug with inline compressed extents.
I didn't tag this one for stable because I want to do individual
tested backports. It's a little tricky and I'd rather do some extra
testing on it along the way"
* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: add missing memset while reading compressed inline extents
Btrfs: fix regression in lock_delalloc_pages
btrfs: remove btrfs_err_str function from uapi/linux/btrfs.h
This is a story about 4 distinct (and very old) btrfs bugs.
Commit c8b978188c ("Btrfs: Add zlib compression support") added
three data corruption bugs for inline extents (bugs #1-3).
Commit 93c82d5750 ("Btrfs: zero page past end of inline file items")
fixed bug #1: uncompressed inline extents followed by a hole and more
extents could get non-zero data in the hole as they were read. The fix
was to add a memset in btrfs_get_extent to zero out the hole.
Commit 166ae5a418 ("btrfs: fix inline compressed read err corruption")
fixed bug #2: compressed inline extents which contained non-zero bytes
might be replaced with zero bytes in some cases. This patch removed an
unhelpful memset from uncompress_inline, but the case where memset is
required was missed.
There is also a memset in the decompression code, but this only covers
decompressed data that is shorter than the ram_bytes from the extent
ref record. This memset doesn't cover the region between the end of the
decompressed data and the end of the page. It has also moved around a
few times over the years, so there's no single patch to refer to.
This patch fixes bug #3: compressed inline extents followed by a hole
and more extents could get non-zero data in the hole as they were read
(i.e. bug #3 is the same as bug #1, but s/uncompressed/compressed/).
The fix is the same: zero out the hole in the compressed case too,
by putting a memset back in uncompress_inline, but this time with
correct parameters.
The last and oldest bug, bug #0, is the cause of the offending inline
extent/hole/extent pattern. Bug #0 is a subtle and mostly-harmless quirk
of behavior somewhere in the btrfs write code. In a few special cases,
an inline extent and hole are allowed to persist where they normally
would be combined with later extents in the file.
A fast reproducer for bug #0 is presented below. A few offending extents
are also created in the wild during large rsync transfers with the -S
flag. A Linux kernel build (git checkout; make allyesconfig; make -j8)
will produce a handful of offending files as well. Once an offending
file is created, it can present different content to userspace each
time it is read.
Bug #0 is at least 4 and possibly 8 years old. I verified every vX.Y
kernel back to v3.5 has this behavior. There are fossil records of this
bug's effects in commits all the way back to v2.6.32. I have no reason
to believe bug #0 wasn't present at the beginning of btrfs compression
support in v2.6.29, but I can't easily test kernels that old to be sure.
It is not clear whether bug #0 is worth fixing. A fix would likely
require injecting extra reads into currently write-only paths, and most
of the exceptional cases caused by bug #0 are already handled now.
Whether we like them or not, bug #0's inline extents followed by holes
are part of the btrfs de-facto disk format now, and we need to be able
to read them without data corruption or an infoleak. So enough about
bug #0, let's get back to bug #3 (this patch).
An example of on-disk structure leading to data corruption found in
the wild:
item 61 key (606890 INODE_ITEM 0) itemoff 9662 itemsize 160
inode generation 50 transid 50 size 47424 nbytes 49141
block group 0 mode 100644 links 1 uid 0 gid 0
rdev 0 flags 0x0(none)
item 62 key (606890 INODE_REF 603050) itemoff 9642 itemsize 20
inode ref index 3 namelen 10 name: DB_File.so
item 63 key (606890 EXTENT_DATA 0) itemoff 8280 itemsize 1362
inline extent data size 1341 ram 4085 compress(zlib)
item 64 key (606890 EXTENT_DATA 4096) itemoff 8227 itemsize 53
extent data disk byte 5367308288 nr 20480
extent data offset 0 nr 45056 ram 45056
extent compression(zlib)
Different data appears in userspace during each read of the 11 bytes
between 4085 and 4096. The extent in item 63 is not long enough to
fill the first page of the file, so a memset is required to fill the
space between item 63 (ending at 4085) and item 64 (beginning at 4096)
with zero.
Here is a reproducer from Liu Bo, which demonstrates another method
of creating the same inline extent and hole pattern:
Using 'page_poison=on' kernel command line (or enable
CONFIG_PAGE_POISONING) run the following:
# touch foo
# chattr +c foo
# xfs_io -f -c "pwrite -W 0 1000" foo
# xfs_io -f -c "falloc 4 8188" foo
# od -x foo
# echo 3 >/proc/sys/vm/drop_caches
# od -x foo
This produce the following on my box:
Correct output: file contains 1000 data bytes followed
by zeros:
0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
*
0001740 cdcd cdcd cdcd cdcd 0000 0000 0000 0000
0001760 0000 0000 0000 0000 0000 0000 0000 0000
*
0020000
Actual output: the data after the first 1000 bytes
will be different each run:
0000000 cdcd cdcd cdcd cdcd cdcd cdcd cdcd cdcd
*
0001740 cdcd cdcd cdcd cdcd 6c63 7400 635f 006d
0001760 5f74 6f43 7400 435f 0053 5f74 7363 7400
0002000 435f 0056 5f74 6164 7400 645f 0062 5f74
(...)
Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Chris Mason <clm@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
The bug is a regression after commit
(da2c7009f6 "btrfs: teach __process_pages_contig about PAGE_LOCK operation")
and commit
(76c0021db8 "Btrfs: use helper to simplify lock/unlock pages").
So if the dirty pages which are under writeback got truncated partially
before we lock the dirty pages, we couldn't find all pages mapping to the
delalloc range, and the bug didn't return an error so it kept going on and
found that the delalloc range got truncated and got to unlock the dirty
pages, and then the ASSERT could caught the error, and showed
-----------------------------------------------------------------------------
assertion failed: page_ops & PAGE_LOCK, file: fs/btrfs/extent_io.c, line: 1716
-----------------------------------------------------------------------------
This fixes the bug by returning the proper -EAGAIN.
Cc: David Sterba <dsterba@suse.com>
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull vfs 'statx()' update from Al Viro.
This adds the new extended stat() interface that internally subsumes our
previous stat interfaces, and allows user mode to specify in more detail
what kind of information it wants.
It also allows for some explicit synchronization information to be
passed to the filesystem, which can be relevant for network filesystems:
is the cached value ok, or do you need open/close consistency, or what?
From David Howells.
Andreas Dilger points out that the first version of the extended statx
interface was posted June 29, 2010:
https://www.spinics.net/lists/linux-fsdevel/msg33831.html
* 'rebased-statx' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
statx: Add a system call to make enhanced file info available
Pull sched.h split-up from Ingo Molnar:
"The point of these changes is to significantly reduce the
<linux/sched.h> header footprint, to speed up the kernel build and to
have a cleaner header structure.
After these changes the new <linux/sched.h>'s typical preprocessed
size goes down from a previous ~0.68 MB (~22K lines) to ~0.45 MB (~15K
lines), which is around 40% faster to build on typical configs.
Not much changed from the last version (-v2) posted three weeks ago: I
eliminated quirks, backmerged fixes plus I rebased it to an upstream
SHA1 from yesterday that includes most changes queued up in -next plus
all sched.h changes that were pending from Andrew.
I've re-tested the series both on x86 and on cross-arch defconfigs,
and did a bisectability test at a number of random points.
I tried to test as many build configurations as possible, but some
build breakage is probably still left - but it should be mostly
limited to architectures that have no cross-compiler binaries
available on kernel.org, and non-default configurations"
* 'WIP.sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (146 commits)
sched/headers: Clean up <linux/sched.h>
sched/headers: Remove #ifdefs from <linux/sched.h>
sched/headers: Remove the <linux/topology.h> include from <linux/sched.h>
sched/headers, hrtimer: Remove the <linux/wait.h> include from <linux/hrtimer.h>
sched/headers, x86/apic: Remove the <linux/pm.h> header inclusion from <asm/apic.h>
sched/headers, timers: Remove the <linux/sysctl.h> include from <linux/timer.h>
sched/headers: Remove <linux/magic.h> from <linux/sched/task_stack.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/init.h>
sched/core: Remove unused prefetch_stack()
sched/headers: Remove <linux/rculist.h> from <linux/sched.h>
sched/headers: Remove the 'init_pid_ns' prototype from <linux/sched.h>
sched/headers: Remove <linux/signal.h> from <linux/sched.h>
sched/headers: Remove <linux/rwsem.h> from <linux/sched.h>
sched/headers: Remove the runqueue_is_locked() prototype
sched/headers: Remove <linux/sched.h> from <linux/sched/hotplug.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/debug.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/nohz.h>
sched/headers: Remove <linux/sched.h> from <linux/sched/stat.h>
sched/headers: Remove the <linux/gfp.h> include from <linux/sched.h>
sched/headers: Remove <linux/rtmutex.h> from <linux/sched.h>
...
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.
The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode. This change is propagated to the vfs_getattr*()
function.
Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.
========
OVERVIEW
========
The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.
A number of requests were gathered for features to be included. The
following have been included:
(1) Make the fields a consistent size on all arches and make them large.
(2) Spare space, request flags and information flags are provided for
future expansion.
(3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
__s64).
(4) Creation time: The SMB protocol carries the creation time, which could
be exported by Samba, which will in turn help CIFS make use of
FS-Cache as that can be used for coherency data (stx_btime).
This is also specified in NFSv4 as a recommended attribute and could
be exported by NFSD [Steve French].
(5) Lightweight stat: Ask for just those details of interest, and allow a
netfs (such as NFS) to approximate anything not of interest, possibly
without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
Dilger] (AT_STATX_DONT_SYNC).
(6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
its cached attributes are up to date [Trond Myklebust]
(AT_STATX_FORCE_SYNC).
And the following have been left out for future extension:
(7) Data version number: Could be used by userspace NFS servers [Aneesh
Kumar].
Can also be used to modify fill_post_wcc() in NFSD which retrieves
i_version directly, but has just called vfs_getattr(). It could get
it from the kstat struct if it used vfs_xgetattr() instead.
(There's disagreement on the exact semantics of a single field, since
not all filesystems do this the same way).
(8) BSD stat compatibility: Including more fields from the BSD stat such
as creation time (st_btime) and inode generation number (st_gen)
[Jeremy Allison, Bernd Schubert].
(9) Inode generation number: Useful for FUSE and userspace NFS servers
[Bernd Schubert].
(This was asked for but later deemed unnecessary with the
open-by-handle capability available and caused disagreement as to
whether it's a security hole or not).
(10) Extra coherency data may be useful in making backups [Andreas Dilger].
(No particular data were offered, but things like last backup
timestamp, the data version number and the DOS archive bit would come
into this category).
(11) Allow the filesystem to indicate what it can/cannot provide: A
filesystem can now say it doesn't support a standard stat feature if
that isn't available, so if, for instance, inode numbers or UIDs don't
exist or are fabricated locally...
(This requires a separate system call - I have an fsinfo() call idea
for this).
(12) Store a 16-byte volume ID in the superblock that can be returned in
struct xstat [Steve French].
(Deferred to fsinfo).
(13) Include granularity fields in the time data to indicate the
granularity of each of the times (NFSv4 time_delta) [Steve French].
(Deferred to fsinfo).
(14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
Note that the Linux IOC flags are a mess and filesystems such as Ext4
define flags that aren't in linux/fs.h, so translation in the kernel
may be a necessity (or, possibly, we provide the filesystem type too).
(Some attributes are made available in stx_attributes, but the general
feeling was that the IOC flags were to ext[234]-specific and shouldn't
be exposed through statx this way).
(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
Michael Kerrisk].
(Deferred, probably to fsinfo. Finding out if there's an ACL or
seclabal might require extra filesystem operations).
(16) Femtosecond-resolution timestamps [Dave Chinner].
(A __reserved field has been left in the statx_timestamp struct for
this - if there proves to be a need).
(17) A set multiple attributes syscall to go with this.
===============
NEW SYSTEM CALL
===============
The new system call is:
int ret = statx(int dfd,
const char *filename,
unsigned int flags,
unsigned int mask,
struct statx *buffer);
The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat(). There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.
Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):
(1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
respect.
(2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
its attributes with the server - which might require data writeback to
occur to get the timestamps correct.
(3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
network filesystem. The resulting values should be considered
approximate.
mask is a bitmask indicating the fields in struct statx that are of
interest to the caller. The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat(). It should be noted that asking for
more information may entail extra I/O operations.
buffer points to the destination for the data. This must be 256 bytes in
size.
======================
MAIN ATTRIBUTES RECORD
======================
The following structures are defined in which to return the main attribute
set:
struct statx_timestamp {
__s64 tv_sec;
__s32 tv_nsec;
__s32 __reserved;
};
struct statx {
__u32 stx_mask;
__u32 stx_blksize;
__u64 stx_attributes;
__u32 stx_nlink;
__u32 stx_uid;
__u32 stx_gid;
__u16 stx_mode;
__u16 __spare0[1];
__u64 stx_ino;
__u64 stx_size;
__u64 stx_blocks;
__u64 __spare1[1];
struct statx_timestamp stx_atime;
struct statx_timestamp stx_btime;
struct statx_timestamp stx_ctime;
struct statx_timestamp stx_mtime;
__u32 stx_rdev_major;
__u32 stx_rdev_minor;
__u32 stx_dev_major;
__u32 stx_dev_minor;
__u64 __spare2[14];
};
The defined bits in request_mask and stx_mask are:
STATX_TYPE Want/got stx_mode & S_IFMT
STATX_MODE Want/got stx_mode & ~S_IFMT
STATX_NLINK Want/got stx_nlink
STATX_UID Want/got stx_uid
STATX_GID Want/got stx_gid
STATX_ATIME Want/got stx_atime{,_ns}
STATX_MTIME Want/got stx_mtime{,_ns}
STATX_CTIME Want/got stx_ctime{,_ns}
STATX_INO Want/got stx_ino
STATX_SIZE Want/got stx_size
STATX_BLOCKS Want/got stx_blocks
STATX_BASIC_STATS [The stuff in the normal stat struct]
STATX_BTIME Want/got stx_btime{,_ns}
STATX_ALL [All currently available stuff]
stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.
Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution. Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.
The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does. The following
attributes map to FS_*_FL flags and are the same numerical value:
STATX_ATTR_COMPRESSED File is compressed by the fs
STATX_ATTR_IMMUTABLE File is marked immutable
STATX_ATTR_APPEND File is append-only
STATX_ATTR_NODUMP File is not to be dumped
STATX_ATTR_ENCRYPTED File requires key to decrypt in fs
Within the kernel, the supported flags are listed by:
KSTAT_ATTR_FS_IOC_FLAGS
[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]
New flags include:
STATX_ATTR_AUTOMOUNT Object is an automount trigger
These are for the use of GUI tools that might want to mark files specially,
depending on what they are.
Fields in struct statx come in a number of classes:
(0) stx_dev_*, stx_blksize.
These are local system information and are always available.
(1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
stx_size, stx_blocks.
These will be returned whether the caller asks for them or not. The
corresponding bits in stx_mask will be set to indicate whether they
actually have valid values.
If the caller didn't ask for them, then they may be approximated. For
example, NFS won't waste any time updating them from the server,
unless as a byproduct of updating something requested.
If the values don't actually exist for the underlying object (such as
UID or GID on a DOS file), then the bit won't be set in the stx_mask,
even if the caller asked for the value. In such a case, the returned
value will be a fabrication.
Note that there are instances where the type might not be valid, for
instance Windows reparse points.
(2) stx_rdev_*.
This will be set only if stx_mode indicates we're looking at a
blockdev or a chardev, otherwise will be 0.
(3) stx_btime.
Similar to (1), except this will be set to 0 if it doesn't exist.
=======
TESTING
=======
The following test program can be used to test the statx system call:
samples/statx/test-statx.c
Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.
Here's some example output. Firstly, an NFS directory that crosses to
another FSID. Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.
[root@andromeda ~]# /tmp/test-statx -A /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:26 Inode: 1703937 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)
Secondly, the result of automounting on that directory.
[root@andromeda ~]# /tmp/test-statx /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:27 Inode: 2 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull more btrfs updates from Chris Mason:
"Btrfs round two.
These are mostly a continuation of Dave Sterba's collection of
cleanups, but Filipe also has some bug fixes and performance
improvements"
* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (69 commits)
btrfs: add dummy callback for readpage_io_failed and drop checks
btrfs: drop checks for mandatory extent_io_ops callbacks
btrfs: document existence of extent_io ops callbacks
btrfs: let writepage_end_io_hook return void
btrfs: do proper error handling in btrfs_insert_xattr_item
btrfs: handle allocation error in update_dev_stat_item
btrfs: remove BUG_ON from __tree_mod_log_insert
btrfs: derive maximum output size in the compression implementation
btrfs: use predefined limits for calculating maximum number of pages for compression
btrfs: export compression buffer limits in a header
btrfs: merge nr_pages input and output parameter in compress_pages
btrfs: merge length input and output parameter in compress_pages
btrfs: constify name of subvolume in creation helpers
btrfs: constify buffers used by compression helpers
btrfs: constify input buffer of btrfs_csum_data
btrfs: constify device path passed to relevant helpers
btrfs: make btrfs_inode_resume_unlocked_dio take btrfs_inode
btrfs: make btrfs_inode_block_unlocked_dio take btrfs_inode
btrfs: Make btrfs_add_nondir take btrfs_inode
btrfs: Make btrfs_add_link take btrfs_inode
...
Instead of including the full <linux/signal.h>, we are going to include the
types-only <linux/signal_types.h> header in <linux/sched.h>, to further
decouple the scheduler header from the signal headers.
This means that various files which relied on the full <linux/signal.h> need
to be updated to gain an explicit dependency on it.
Update the code that relies on sched.h's inclusion of the <linux/signal.h> header.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make extent_io_ops::readpage_io_failed_hook callback mandatory and
define a dummy function for btrfs_extent_io_ops. As the failed IO
callback is not performance critical, the branch vs extra trade off does
not hurt.
Signed-off-by: David Sterba <dsterba@suse.com>
We know that eadpage_end_io_hook, submit_bio_hook and merge_bio_hook are
always defined so we can drop the checks before we call them.
Signed-off-by: David Sterba <dsterba@suse.com>
Some of the callbacks defined in btree_extent_io_ops and
btrfs_extent_io_ops do always exist so we don't need to check the
existence before each call. This patch just reorders the definition and
documents which are mandatory/optional.
Signed-off-by: David Sterba <dsterba@suse.com>
There's no error path in any of the instances, always return 0.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The space check in btrfs_insert_xattr_item is duplicated in it's caller
(do_setxattr) so we won't hit the BUG_ON. Continuing without any check
could be disasterous so turn it to a proper error handling.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All callers dereference the 'tm' parameter before it gets to this
function, the NULL check does not make much sense here.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The value of max_out can be calculated from the parameters passed to the
compressors, which is number of pages and the page size, and we don't
have to needlessly pass it around.
Signed-off-by: David Sterba <dsterba@suse.com>
Move the buffer limit definitions out of compress_file_range.
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The parameter saying how many pages can be allocated at maximum can be
merged with the output page counter, to save some stack space. The
compression implementation will sink the parameter to a local variable
so everything works as before.
The nr_pages variables can also be simply merged in compress_file_range
into one.
Signed-off-by: David Sterba <dsterba@suse.com>
The length parameter is basically duplicated for input and output in the
top level caller of the compress_pages chain. We can simply use one
variable for that and reduce stack consumption. The compression
implementation will sink the parameter to a local variable so everything
works as before.
Signed-off-by: David Sterba <dsterba@suse.com>
In addition to changing the signature, this patch also switches
all the functions which are used as an argument to also take btrfs_inode.
Namely those are: btrfs_get_extent and btrfs_get_extent_filemap.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Replace all 1 << inode->i_blkbits and (1 << inode->i_blkbits) in fs
branch.
This patch also fixes multiple checkpatch warnings: WARNING: Prefer
'unsigned int' to bare use of 'unsigned'
Thanks to Andrew Morton for suggesting more appropriate function instead
of macro.
[geliangtang@gmail.com: truncate: use i_blocksize()]
Link: http://lkml.kernel.org/r/9c8b2cd83c8f5653805d43debde9fa8817e02fc4.1484895804.git.geliangtang@gmail.com
Link: http://lkml.kernel.org/r/1481319905-10126-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull btrfs updates from Chris Mason:
"This has a series of fixes and cleanups that Dave Sterba has been
collecting.
There is a pretty big variety here, cleaning up internal APIs and
fixing corner cases"
* 'for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (124 commits)
Btrfs: use the correct type when creating cow dio extent
Btrfs: fix deadlock between dedup on same file and starting writeback
btrfs: use btrfs_debug instead of pr_debug in transaction abort
btrfs: btrfs_truncate_free_space_cache always allocates path
btrfs: free-space-cache, clean up unnecessary root arguments
btrfs: convert btrfs_inc_block_group_ro to accept fs_info
btrfs: flush_space always takes fs_info->fs_root
btrfs: pass fs_info to (more) routines that are only called with extent_root
btrfs: qgroup: Move half of the qgroup accounting time out of commit trans
btrfs: remove unused parameter from adjust_slots_upwards
btrfs: remove unused parameters from __btrfs_write_out_cache
btrfs: remove unused parameter from cleanup_write_cache_enospc
btrfs: remove unused parameter from __add_inode_ref
btrfs: remove unused parameter from clone_copy_inline_extent
btrfs: remove unused parameters from btrfs_cmp_data
btrfs: remove unused parameter from __add_inline_refs
btrfs: remove unused parameters from scrub_setup_wr_ctx
btrfs: remove unused parameter from create_snapshot
btrfs: remove unused parameter from init_first_rw_device
btrfs: remove unused parameter from __btrfs_alloc_chunk
...
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.
Remove the vma parameter to simplify things.
[arnd@arndb.de: fix ARM build]
Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Before attempting to split a leaf we try to migrate items from the leaf to
its right and left siblings. We start by trying to move items into the
rigth sibling and, if the new item is meant to be inserted at the end of
our leaf, we try to free from our leaf an amount of bytes equal to the
number of bytes used by the new item, by setting the variable space_needed
to the byte size of that new item. However if we fail to move enough items
to the right sibling due to lack of space in that sibling, we then try
to move items into the left sibling, and in that case we try to free
an amount equal to the size of the new item from our leaf, when we need
only to free an amount corresponding to the size of the new item minus
the current free space of our leaf. So make sure that before we try to
move items to the left sibling we do set the variable space_needed with
a value corresponding to the new item's size minus the leaf's current
free space.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
If we have a file with an implicit hole (NO_HOLES feature enabled) that
has an extent following the hole, delayed writes against regions of the
file behind the hole happened before but were not yet flushed and then
we truncate the file to a smaller size that lies inside the hole, we
end up persisting a wrong disk_i_size value for our inode that leads to
data loss after umounting and mounting again the filesystem or after
the inode is evicted and loaded again.
This happens because at inode.c:btrfs_truncate_inode_items() we end up
setting last_size to the offset of the extent that we deleted and that
followed the hole. We then pass that value to btrfs_ordered_update_i_size()
which updates the inode's disk_i_size to a value smaller then the offset
of the buffered (delayed) writes.
Example reproducer:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0x01 0K 32K" /mnt/foo
$ xfs_io -d -c "pwrite -S 0x02 -b 32K 64K 32K" /mnt/foo
$ xfs_io -c "truncate 60K" /mnt/foo
--> inode's disk_i_size updated to 0
$ md5sum /mnt/foo
3c5ca3c3ab42f4b04d7e7eb0b0d4d806 /mnt/foo
$ umount /dev/sdb
$ mount /dev/sdb /mnt
$ md5sum /mnt/foo
d41d8cd98f00b204e9800998ecf8427e /mnt/foo
--> Empty file, all data lost!
Cc: <stable@vger.kernel.org> # 3.14+
Fixes: 16e7549f04 ("Btrfs: incompatible format change to remove hole extents")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
When using the NO_HOLES feature, during an incremental send we often issue
write operations for holes when we should not, because that range is already
a hole in the destination snapshot. While that does not change the contents
of the file at the receiver, it avoids preservation of file holes, leading
to wasted disk space and extra IO during send/receive.
A couple examples where the holes are not preserved follows.
$ mkfs.btrfs -O no-holes -f /dev/sdb
$ mount /dev/sdb /mnt
$ xfs_io -f -c "pwrite -S 0xaa 0 4K" /mnt/foo
$ xfs_io -f -c "pwrite -S 0xaa 0 4K" -c "pwrite -S 0xbb 1028K 4K" /mnt/bar
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
# Now add one new extent to our first test file, increasing its size and
# leaving a 1Mb hole between the first extent and this new extent.
$ xfs_io -c "pwrite -S 0xbb 1028K 4K" /mnt/foo
# Now overwrite the last extent of our second test file.
$ xfs_io -c "pwrite -S 0xcc 1028K 4K" /mnt/bar
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ xfs_io -r -c "fiemap -v" /mnt/snap2/foo
/mnt/snap2/foo:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..7]: 25088..25095 8 0x2000
1: [8..2055]: hole 2048
2: [2056..2063]: 24576..24583 8 0x2001
$ xfs_io -r -c "fiemap -v" /mnt/snap2/bar
/mnt/snap2/bar:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..7]: 25096..25103 8 0x2000
1: [8..2055]: hole 2048
2: [2056..2063]: 24584..24591 8 0x2001
$ btrfs send /mnt/snap1 -f /tmp/1.snap
$ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap
$ umount /mnt
# It's not relevant to enable no-holes in the new filesystem.
$ mkfs.btrfs -O no-holes -f /dev/sdc
$ mount /dev/sdc /mnt
$ btrfs receive /mnt -f /tmp/1.snap
$ btrfs receive /mnt -f /tmp/2.snap
$ xfs_io -r -c "fiemap -v" /mnt/snap2/foo
/mnt/snap2/foo:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..7]: 24576..24583 8 0x2000
1: [8..2063]: 25624..27679 2056 0x1
$ xfs_io -r -c "fiemap -v" /mnt/snap2/bar
/mnt/snap2/bar:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..7]: 24584..24591 8 0x2000
1: [8..2063]: 27680..29735 2056 0x1
The holes do not exist in the second filesystem and they were replaced
with extents filled with the byte 0x00, making each file take 1032Kb of
space instead of 8Kb.
So fix this by not issuing the write operations consisting of buffers
filled with the byte 0x00 when the destination snapshot already has a
hole for the respective range.
A test case for fstests will follow soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
We log holes explicitly by using file extent items, however when replaying
a log tree, if a logged file extent item corresponds to a hole and the
NO_HOLES feature is enabled we do not need to copy the file extent item
into the fs/subvolume tree, as the absence of such file extent items is
the purpose of the NO_HOLES feature. So skip the copying of file extent
items representing holes when the NO_HOLES feature is enabled.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
When falling back from a nocow write to a regular cow write, we were
leaking the subvolume writers counter in 2 situations, preventing
snapshot creation from ever completing in the future, as it waits
for that counter to go down to zero before the snapshot creation
starts.
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[Improved changelog and subject]
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Very often we have the checksums for an extent spread in multiple items
in the checksums tree, and currently the algorithm to delete them starts
by looking for them one by one and then deleting them one by one, which
is not optimal since each deletion involves shifting all the other items
in the leaf and when the leaf reaches some low threshold, to move items
off the leaf into its left and right neighbor leafs. Also, after each
item deletion we release our search path and start a new search for other
checksums items.
So optimize this by deleting in bulk all the items in the same leaf that
contain checksums for the extent being freed.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
When both the parent and send snapshots have a directory inode with the
same number but different generations (therefore they are different
inodes) and both have an entry with the same name, an incremental send
stream will contain an invalid rmdir operation that refers to the
orphanized name of the inode from the parent snapshot.
The following example scenario shows how this happens.
Parent snapshot:
.
|---- d259_old/ (ino 259, gen 9)
| |---- d1/ (ino 258, gen 9)
|
|---- f (ino 257, gen 9)
Send snapshot:
.
|---- d258/ (ino 258, gen 7)
|---- d259/ (ino 259, gen 7)
|---- d1/ (ino 257, gen 7)
When the kernel is processing inode 258 it notices that in both snapshots
there is an inode numbered 259 that is a parent of an inode 258. However
it ignores the fact that the inodes numbered 259 have different generations
in both snapshots, which means they are effectively different inodes.
Then it checks that both inodes 259 have a dentry named "d1" and because
of that it issues a rmdir operation with orphanized name of the inode 258
from the parent snapshot. This happens at send.c:process_record_refs(),
which calls send.c:did_overwrite_first_ref() that returns true and because
of that later on at process_recorded_refs() such rmdir operation is issued
because the inode being currently processed (258) is a directory and it
was deleted in the send snapshot (and replaced with another inode that has
the same number and is a directory too).
Fix this issue by comparing the generations of parent directory inodes
that have the same number and make send.c:did_overwrite_first_ref() when
the generations are different.
The following steps reproduce the problem.
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ touch /mnt/f
$ mkdir /mnt/d1
$ mkdir /mnt/d259_old
$ mv /mnt/d1 /mnt/d259_old/d1
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ btrfs send /mnt/snap1 -f /tmp/1.snap
$ umount /mnt
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt
$ mkdir /mnt/d1
$ mkdir /mnt/dir258
$ mkdir /mnt/dir259
$ mv /mnt/d1 /mnt/dir259/d1
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs receive /mnt/ -f /tmp/1.snap
# Take note that once the filesystem is created, its current
# generation has value 7 so the inodes from the second snapshot all have
# a generation value of 7. And after receiving the first snapshot
# the filesystem is at a generation value of 10, because the call to
# create the second snapshot bumps the generation to 8 (the snapshot
# creation ioctl does a transaction commit), the receive command calls
# the snapshot creation ioctl to create the first snapshot, which bumps
# the filesystem's generation to 9, and finally when the receive
# operation finishes it calls an ioctl to transition the first snapshot
# (snap1) from RW mode to RO mode, which does another transaction commit
# and bumps the filesystem's generation to 10. This means all the inodes
# in the first snapshot (snap1) have a generation value of 9.
$ rm -f /tmp/1.snap
$ btrfs send /mnt/snap1 -f /tmp/1.snap
$ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap
$ umount /mnt
$ mkfs.btrfs -f /dev/sdd
$ mount /dev/sdd /mnt
$ btrfs receive /mnt -f /tmp/1.snap
$ btrfs receive -vv /mnt -f /tmp/2.snap
receiving snapshot mysnap2 uuid=9c03962f-f620-0047-9f98-32e5a87116d9, ctransid=7 parent_uuid=d17a6e3f-14e5-df4f-be39-a7951a5399aa, parent_ctransid=9
utimes
unlink f
mkdir o257-7-0
mkdir o259-7-0
rename o257-7-0 -> o259-7-0/d1
chown o259-7-0/d1 - uid=0, gid=0
chmod o259-7-0/d1 - mode=0755
utimes o259-7-0/d1
rmdir o258-9-0
ERROR: rmdir o258-9-0 failed: No such file or directory
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[Rewrote changelog to be more precise and clear]
Signed-off-by: Filipe Manana <fdmanana@suse.com>
When we are checking if we need to delay the rename operation for an
inode we not checking if a parent inode that exists in the send and
parent snapshots is really the same inode or not, that is, we are not
comparing the generation number of the parent inode in the send and
parent snapshots. Not only this results in unnecessarily delaying a
rename operation but also can later on make us generate an incorrect
name for a new inode in the send snapshot that has the same number
as another inode in the parent snapshot but a different generation.
Here follows an example where this happens.
Parent snapshot:
. (ino 256, gen 3)
|--- dir258/ (ino 258, gen 7)
| |--- dir257/ (ino 257, gen 7)
|
|--- dir259/ (ino 259, gen 7)
Send snapshot:
. (ino 256, gen 3)
|--- file258 (ino 258, gen 10)
|
|--- new_dir259/ (ino 259, gen 10)
|--- dir257/ (ino 257, gen 7)
The following steps happen when computing the incremental send stream:
1) When processing inode 257, its new parent is created using its orphan
name (o257-21-0), and the rename operation for inode 257 is delayed
because its new parent (inode 259) was not yet processed - this
decision to delay the rename operation does not make much sense
because the inode 259 in the send snapshot is a new inode, it's not
the same as inode 259 in the parent snapshot.
2) When processing inode 258 we end up delaying its rmdir operation,
because inode 257 was not yet renamed (moved away from the directory
inode 258 represents). We also create the new inode 258 using its
orphan name "o258-10-0", then rename it to its final name of "file258"
and then issue a truncate operation for it. However this truncate
operation contains an incorrect name, which corresponds to the orphan
name and not to the final name, which makes the receiver fail. This
happens because when we attempt to compute the inode's current name
we verify that there's another inode with the same number (258) that
has its rmdir operation pending and because of that we generate an
orphan name for the new inode 258 (we do this in the function
get_cur_path()).
Fix this by not delayed the rename operation of an inode if it has parents
with the same number but different generations in both snapshots.
The following steps reproduce this example scenario.
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ mkdir /mnt/dir257
$ mkdir /mnt/dir258
$ mkdir /mnt/dir259
$ mv /mnt/dir257 /mnt/dir258/dir257
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ mv /mnt/dir258/dir257 /mnt/dir257
$ rmdir /mnt/dir258
$ rmdir /mnt/dir259
# Remount the filesystem so that the next created inodes will have the
# numbers 258 and 259. This is because when a filesystem is mounted,
# btrfs sets the subvolume's inode counter to a value corresponding to
# the highest inode number in the subvolume plus 1. This inode counter
# is used to assign a unique number to each new inode and it's
# incremented by 1 after very inode creation.
# Note: we unmount and then mount instead of doing a mount with
# "-o remount" because otherwise the inode counter remains at value 260.
$ umount /mnt
$ mount /dev/sdb /mnt
$ touch /mnt/file258
$ mkdir /mnt/new_dir259
$ mv /mnt/dir257 /mnt/new_dir259/dir257
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs send /mnt/snap1 -f /tmp/1.snap
$ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap
$ umount /mnt
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt
$ btrfs receive /mnt -f /tmo/1.snap
$ btrfs receive /mnt -f /tmo/2.snap -vv
receiving snapshot mysnap2 uuid=e059b6d1-7f55-f140-8d7c-9a3039d23c97, ctransid=10 parent_uuid=77e98cb6-8762-814f-9e05-e8ba877fc0b0, parent_ctransid=7
utimes
mkdir o259-10-0
rename dir258 -> o258-7-0
utimes
mkfile o258-10-0
rename o258-10-0 -> file258
utimes
truncate o258-10-0 size=0
ERROR: truncate o258-10-0 failed: No such file or directory
Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Under certain situations, an incremental send operation can fail due to a
premature attempt to create a new top level inode (a direct child of the
subvolume/snapshot root) whose name collides with another inode that was
removed from the send snapshot.
Consider the following example scenario.
Parent snapshot:
. (ino 256, gen 8)
|---- a1/ (ino 257, gen 9)
|---- a2/ (ino 258, gen 9)
Send snapshot:
. (ino 256, gen 3)
|---- a2/ (ino 257, gen 7)
In this scenario, when receiving the incremental send stream, the btrfs
receive command fails like this (ran in verbose mode, -vv argument):
rmdir a1
mkfile o257-7-0
rename o257-7-0 -> a2
ERROR: rename o257-7-0 -> a2 failed: Is a directory
What happens when computing the incremental send stream is:
1) An operation to remove the directory with inode number 257 and
generation 9 is issued.
2) An operation to create the inode with number 257 and generation 7 is
issued. This creates the inode with an orphanized name of "o257-7-0".
3) An operation rename the new inode 257 to its final name, "a2", is
issued. This is incorrect because inode 258, which has the same name
and it's a child of the same parent (root inode 256), was not yet
processed and therefore no rmdir operation for it was yet issued.
The rename operation is issued because we fail to detect that the
name of the new inode 257 collides with inode 258, because their
parent, a subvolume/snapshot root (inode 256) has a different
generation in both snapshots.
So fix this by ignoring the generation value of a parent directory that
matches a root inode (number 256) when we are checking if the name of the
inode currently being processed collides with the name of some other
inode that was not yet processed.
We can achieve this scenario of different inodes with the same number but
different generation values either by mounting a filesystem with the inode
cache option (-o inode_cache) or by creating and sending snapshots across
different filesystems, like in the following example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ mkdir /mnt/a1
$ mkdir /mnt/a2
$ btrfs subvolume snapshot -r /mnt /mnt/snap1
$ btrfs send /mnt/snap1 -f /tmp/1.snap
$ umount /mnt
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt
$ touch /mnt/a2
$ btrfs subvolume snapshot -r /mnt /mnt/snap2
$ btrfs receive /mnt -f /tmp/1.snap
# Take note that once the filesystem is created, its current
# generation has value 7 so the inode from the second snapshot has
# a generation value of 7. And after receiving the first snapshot
# the filesystem is at a generation value of 10, because the call to
# create the second snapshot bumps the generation to 8 (the snapshot
# creation ioctl does a transaction commit), the receive command calls
# the snapshot creation ioctl to create the first snapshot, which bumps
# the filesystem's generation to 9, and finally when the receive
# operation finishes it calls an ioctl to transition the first snapshot
# (snap1) from RW mode to RO mode, which does another transaction commit
# and bumps the filesystem's generation to 10.
$ rm -f /tmp/1.snap
$ btrfs send /mnt/snap1 -f /tmp/1.snap
$ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.snap
$ umount /mnt
$ mkfs.btrfs -f /dev/sdd
$ mount /dev/sdd /mnt
$ btrfs receive /mnt /tmp/1.snap
# Receive of snapshot snap2 used to fail.
$ btrfs receive /mnt /tmp/2.snap
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[Rewrote changelog to be more precise and clear]
Signed-off-by: Filipe Manana <fdmanana@suse.com>
'BTRFS_ORDERED_REGULAR' was introduced for the cow case in patch
'Btrfs: specify a new ordered extent type for create_io_em',
but it missed the directIO cow case.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
Commit e5d6b12fe1 (Btrfs: don't WARN() in btrfs_transaction_abort() for
IO errors) added a pr_debug call to be printed when a transaction is
aborted with -EIO instead of WARN. btrfs_debug prints which file system
the message is associated with so let's use that instead.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_truncate_free_space_cache always allocates a btrfs_path structure
but only uses it when the caller passes a block group. Let's move the
allocation and free into the conditional.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The free space cache APIs accept a root but always use the tree root.
Also, btrfs_truncate_free_space_cache accepts a root AND an inode but
the inode always points to the root anyway, so let's just pass the inode.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_inc_block_group_ro is either passed the extent root or the dev
root, but it doesn't do anything with the dev tree. Let's convert
to passing an fs_info and using the extent root.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We don't need to pass a root to flush_space since it always uses
the fs_root.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Outside of interactions with qgroups, the roots passed in extent-tree.c
are usually passed to ensure that we don't do refcounts on log trees or
to get the allocation profile for an allocation request. Otherwise, it
operates on the extent root. This patch converts some more routines in
extent-tree.c that are always called with the extent root to accept
an fs_info instead.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Just as Filipe pointed out, the most time consuming parts of qgroup are
btrfs_qgroup_account_extents() and
btrfs_qgroup_prepare_account_extents().
Which both call btrfs_find_all_roots() to get old_roots and new_roots
ulist.
What makes things worse is, we're calling that expensive
btrfs_find_all_roots() at transaction committing time with
TRANS_STATE_COMMIT_DOING, which will blocks all incoming transaction.
Such behavior is necessary for @new_roots search as current
btrfs_find_all_roots() can't do it correctly so we do call it just
before switch commit roots.
However for @old_roots search, it's not necessary as such search is
based on commit_root, so it will always be correct and we can move it
out of transaction committing.
This patch moves the @old_roots search part out of
commit_transaction(), so in theory we can half the time qgroup time
consumption at commit_transaction().
But please note that, this won't speedup qgroup overall, the total time
consumption is still the same, just reduce the performance stall.
Cc: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Both unused after the call to update_cache_item has been moved to
__btrfs_wait_cache_io.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Unused since the helper has been split, eb used in the caller.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
After the page locking has been reworked, we get all pages prepared via
cmp_pages.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The name parameters have never been used, as the name is passed via the
dentry.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The 'device' used to be added in that function, but now it's done by the
caller.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Never used for anything meaningful since we have our own superblock
filler.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The 'tree' was used to call locking hook that does not exist anymore.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The logic has been updated in "Btrfs: make mapping->writeback_index
point to the last written page" (a91326679f) and page is not
needed anymore.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This used to hold number of maximum pages to allocate, but this is now
limited by BIO_MAX_PAGES. The local are now unused and removed as well.
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba