Commit Graph

4009 Commits

Author SHA1 Message Date
Filipe Manana 425b5dafc8 Btrfs: remove unnecessary inode generation lookup in send
No need to search in the send tree for the generation number of the inode,
we already have it in the recorded_ref structure passed to us.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:28 -07:00
Filipe Manana 21543baddc Btrfs: fix race when updating existing ref head
While we update an existing ref head's extent_op, we're not holding
its spinlock, so while we're updating its extent_op contents (key,
flags) we can have a task running __btrfs_run_delayed_refs() that
holds the ref head's lock and sets its extent_op to NULL right after
the task updating the ref head just checked its extent_op was not NULL.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:28 -07:00
Qu Wenruo c3a468915a btrfs: Add trace for btrfs_workqueue alloc/destroy
Since most of the btrfs_workqueue is printed as pointer address,
for easier analysis, add trace for btrfs_workqueue alloc/destroy.
So it is possible to determine the workqueue that a given work belongs
to(by comparing the wq pointer address with alloc trace event).

Signed-off-by: Qu Wenruo <quenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:28 -07:00
Filipe Manana f094c9bd3e Btrfs: less fs tree lock contention when using autodefrag
When finding new extents during an autodefrag, don't do so many fs tree
lookups to find an extent with a size smaller then the target treshold.
Instead, after each fs tree forward search immediately unlock upper
levels and process the entire leaf while holding a read lock on the leaf,
since our leaf processing is very fast.
This reduces lock contention, allowing for higher concurrency when other
tasks want to write/update items related to other inodes in the fs tree,
as we're not holding read locks on upper tree levels while processing the
leaf and we do less tree searches.

Test:

    sysbench --test=fileio --file-num=512 --file-total-size=16G \
       --file-test-mode=rndrw --num-threads=32 --file-block-size=32768 \
       --file-rw-ratio=3 --file-io-mode=sync --max-time=1800 \
       --max-requests=10000000000 [prepare|run]

(fileystem mounted with -o autodefrag, averages of 5 runs)

Before this change: 58.852Mb/sec throughtput, read 77.589Gb, written 25.863Gb
After this change:  63.034Mb/sec throughtput, read 83.102Gb, written 27.701Gb

Test machine: quad core intel i5-3570K, 32Gb of RAM, SSD.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Guangyu Sun 72de6b5393 Btrfs: return EPERM when deleting a default subvolume
The error message is confusing:

 # btrfs sub delete /mnt/mysub/
 Delete subvolume '/mnt/mysub'
 ERROR: cannot delete '/mnt/mysub' - Directory not empty

The error message does not make sense to me: It's not about deleting a
directory but it's a subvolume, and it doesn't matter if the subvolume is
empty or not.

Maybe EPERM or is more appropriate in this case, combined with an explanatory
kernel log message. (e.g. "subvolume with ID 123 cannot be deleted because
it is configured as default subvolume.")

Reported-by: Koen De Wit <koen.de.wit@oracle.com>
Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Filipe Manana ef66af101a Btrfs: add missing kfree in btrfs_destroy_workqueue
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Filipe Manana 308d9800b2 Btrfs: cache extent states in defrag code path
When locking file ranges in the inode's io_tree, cache the first
extent state that belongs to the target range, so that when unlocking
the range we don't need to search in the io_tree again, reducing cpu
time and making and therefore holding the io_tree's lock for a shorter
period.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Josef Bacik 3bbb24b20a Btrfs: fix deadlock with nested trans handles
Zach found this deadlock that would happen like this

btrfs_end_transaction <- reduce trans->use_count to 0
  btrfs_run_delayed_refs
    btrfs_cow_block
      find_free_extent
	btrfs_start_transaction <- increase trans->use_count to 1
          allocate chunk
	btrfs_end_transaction <- decrease trans->use_count to 0
	  btrfs_run_delayed_refs
	    lock tree block we are cowing above ^^

We need to only decrease trans->use_count if it is above 1, otherwise leave it
alone.  This will make nested trans be the only ones who decrease their added
ref, and will let us get rid of the trans->use_count++ hack if we have to commit
the transaction.  Thanks,

cc: stable@vger.kernel.org
Reported-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Tested-by: Zach Brown <zab@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Theodore Ts'o 02b9984d64 fs: push sync_filesystem() down to the file system's remount_fs()
Previously, the no-op "mount -o mount /dev/xxx" operation when the
file system is already mounted read-write causes an implied,
unconditional syncfs().  This seems pretty stupid, and it's certainly
documented or guaraunteed to do this, nor is it particularly useful,
except in the case where the file system was mounted rw and is getting
remounted read-only.

However, it's possible that there might be some file systems that are
actually depending on this behavior.  In most file systems, it's
probably fine to only call sync_filesystem() when transitioning from
read-write to read-only, and there are some file systems where this is
not needed at all (for example, for a pseudo-filesystem or something
like romfs).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Jan Kara <jack@suse.cz>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Anders Larsen <al@alarsen.net>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: Petr Vandrovec <petr@vandrovec.name>
Cc: xfs@oss.sgi.com
Cc: linux-btrfs@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: codalist@coda.cs.cmu.edu
Cc: linux-ext4@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: fuse-devel@lists.sourceforge.net
Cc: cluster-devel@redhat.com
Cc: linux-mtd@lists.infradead.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: linux-nilfs@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: reiserfs-devel@vger.kernel.org
2014-03-13 10:14:33 -04:00
Miao Xie 573bfb72f7 Btrfs: fix possible empty list access when flushing the delalloc inodes
We didn't have a lock to protect the access to the delalloc inodes list, that is
we might access a empty delalloc inodes list if someone start flushing delalloc
inodes because the delalloc inodes were moved into a other list temporarily.
Fix it by wrapping the access with a lock.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:29 -04:00
Miao Xie 31f3d255c6 Btrfs: split the global ordered extents mutex
When we create a snapshot, we just need wait the ordered extents in
the source fs/file root, but because we use the global mutex to protect
this ordered extents list of the source fs/file root to avoid accessing
a empty list, if someone got the mutex to access the ordered extents list
of the other fs/file root, we had to wait.

This patch splits the above global mutex, now every fs/file root has
its own mutex to protect its own list.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:28 -04:00
Miao Xie 6c255e67ce Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
We needn't flush all delalloc inodes when we doesn't get s_umount lock,
or we would make the tasks wait for a long time.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:27 -04:00
Miao Xie 24af7dd188 Btrfs: reclaim delalloc metadata more aggressively
generic/074 in xfstests failed sometimes because of the enospc error,
the reason of this problem is that we just reclaimed the space we need
from the reserved space for delalloc, and then tried to reserve the space,
but if some task did no-flush reservation between the above reclamation
and reservation,
	Task1			Task2
	shrink_delalloc()
	reclaim 1 block
	(The space that can
	 be reserved now is 1
	 block)
				do no-flush reservation
				reserve 1 block
				(The space that can
				 be reserved now is 0
				 block)
	reserving 1 block failed
the reservation of Task1 failed, but in fact, there was enough space to
reserve if we could reclaim more space before.

Fix this problem by the aggressive reclamation of the reserved delalloc
metadata space.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:26 -04:00
Miao Xie 0424c54897 Btrfs: remove unnecessary lock in may_commit_transaction()
The reason is:
- The per-cpu counter has its own lock to protect itself.
- Here we needn't get a exact value.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:25 -04:00
Miao Xie b88935bf98 Btrfs: remove the unnecessary flush when preparing the pages
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:25 -04:00
Miao Xie 41bd9ca459 Btrfs: just do dirty page flush for the inode with compression before direct IO
As the comment in the btrfs_direct_IO says, only the compressed pages need be
flush again to make sure they are on the disk, but the common pages needn't,
so we add a if statement to check if the inode has compressed pages or not,
if no, skip the flush.

And in order to prevent the write ranges from intersecting, we need wait for
the running ordered extents. But the current code waits for them twice, one
is done before the direct IO starts (in btrfs_wait_ordered_range()), the other
is before we get the blocks, it is unnecessary. because we can do the direct
IO without holding i_mutex, it means that the intersected ordered extents may
happen during the direct IO, the first wait can not avoid this problem. So we
use filemap_fdatawrite_range() instead of btrfs_wait_ordered_range() to remove
the first wait.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:24 -04:00
Miao Xie af7a65097b Btrfs: wake up the tasks that wait for the io earlier
The tasks that wait for the IO_DONE flag just care about the io of the dirty
pages, so it is better to wake up them immediately after all the pages are
written, not the whole process of the io completes.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:23 -04:00
Miao Xie 8b9d83cd6b Btrfs: fix early enospc due to the race of the two ordered extent wait
btrfs_wait_ordered_roots() moves all the list entries to a new list,
and then deals with them one by one. But if the other task invokes this
function at that time, it would get a empty list. It makes the enospc
error happens more early. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:22 -04:00
Miao Xie 8257b2dc3c Btrfs: introduce btrfs_{start, end}_nocow_write() for each subvolume
If the snapshot creation happened after the nocow write but before the dirty
data flush, we would fail to flush the dirty data because of no space.

So we must keep track of when those nocow write operations start and when they
end, if there are nocow writers, the snapshot creators must wait. In order
to implement this function, I introduce btrfs_{start, end}_nocow_write(),
which is similar to mnt_{want,drop}_write().

These two functions are only used for nocow file write operations.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:22 -04:00
Qu Wenruo 52483bc26f btrfs: Add ftrace for btrfs_workqueue
Add ftrace for btrfs_workqueue for further workqueue tunning.
This patch needs to applied after the workqueue replace patchset.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:21 -04:00
Qu Wenruo 6db8914f97 btrfs: Cleanup the btrfs_workqueue related function type
The new btrfs_workqueue still use open-coded function defition,
this patch will change them into btrfs_func_t type which is much the
same as kernel workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:20 -04:00
Liu Bo 2131bcd38b Btrfs: add readahead for send_write
Btrfs send reads data from disk and then writes to a stream via pipe or
a file via flush.

Currently we're going to read each page a time, so every page results
in a disk read, which is not friendly to disks, esp. HDD.  Given that,
the performance can be gained by adding readahead for those pages.

Here is a quick test:
$ btrfs subvolume create send
$ xfs_io -f -c "pwrite 0 1G" send/foobar
$ btrfs subvolume snap -r send ro
$ time "btrfs send ro -f /dev/null"

           w/o             w
real    1m37.527s       0m9.097s
user    0m0.122s        0m0.086s
sys     0m53.191s       0m12.857s

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:19 -04:00
Liu Bo a4d96d6254 Btrfs: share the same code for __record_{new,deleted}_ref
This has no functional change, only picks out the same part of two functions,
and makes it shared.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:19 -04:00
Filipe Manana fcbd2154d1 Btrfs: avoid unnecessary utimes update in incremental send
When we're finishing processing of an inode, if we're dealing with a
directory inode that has a pending move/rename operation, we don't
need to send a utimes update instruction to the send stream, as we'll
do it later after doing the move/rename operation. Therefore we save
some time here building paths and doing btree lookups.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:18 -04:00
Filipe Manana e2127cf008 Btrfs: make defrag not fragment files when using prealloc extents
When using prealloc extents, a file defragment operation may actually
fragment the file and increase the amount of data space used by the file.
This change fixes that behaviour.

Example:

$ mkfs.btrfs -f /dev/sdb3
$ mount /dev/sdb3 /mnt
$ cd /mnt
$ xfs_io -f -c 'falloc 0 1048576' foobar && sync
$ xfs_io -c 'pwrite -S 0xff -b 100000 5000 100000' foobar
$ xfs_io -c 'pwrite -S 0xac -b 100000 200000 100000' foobar
$ xfs_io -c 'pwrite -S 0xe1 -b 100000 900000 100000' foobar && sync

Before defragmenting the file:

$ btrfs filesystem df /mnt
Data, single: total=8.00MiB, used=1.25MiB
System, DUP: total=8.00MiB, used=16.00KiB
System, single: total=4.00MiB, used=0.00
Metadata, DUP: total=1.00GiB, used=112.00KiB
Metadata, single: total=8.00MiB, used=0.00

$ btrfs-debug-tree /dev/sdb3
(...)
	item 6 key (257 EXTENT_DATA 0) itemoff 15810 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 0 nr 4096
	item 7 key (257 EXTENT_DATA 4096) itemoff 15757 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 4096 nr 102400 ram 1048576
		extent compression 0
	item 8 key (257 EXTENT_DATA 106496) itemoff 15704 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 106496 nr 90112
	item 9 key (257 EXTENT_DATA 196608) itemoff 15651 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 196608 nr 106496 ram 1048576
		extent compression 0
	item 10 key (257 EXTENT_DATA 303104) itemoff 15598 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 303104 nr 593920
	item 11 key (257 EXTENT_DATA 897024) itemoff 15545 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 897024 nr 106496 ram 1048576
		extent compression 0
	item 12 key (257 EXTENT_DATA 1003520) itemoff 15492 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 1003520 nr 45056
(...)

Now defragmenting the file results in more data space used than before:

$ btrfs filesystem defragment -f foobar && sync
$ btrfs filesystem df /mnt
Data, single: total=8.00MiB, used=1.55MiB
System, DUP: total=8.00MiB, used=16.00KiB
System, single: total=4.00MiB, used=0.00
Metadata, DUP: total=1.00GiB, used=112.00KiB
Metadata, single: total=8.00MiB, used=0.00

And the corresponding file extent items are now no longer perfectly sequential
as before, and we're now needlessly using more space from data block groups:

$ btrfs-debug-tree /dev/sdb3
(...)
	item 6 key (257 EXTENT_DATA 0) itemoff 15810 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 0 nr 4096 ram 1048576
		extent compression 0
	item 7 key (257 EXTENT_DATA 4096) itemoff 15757 itemsize 53
		extent data disk byte 13893632 nr 102400
		extent data offset 0 nr 102400 ram 102400
		extent compression 0
	item 8 key (257 EXTENT_DATA 106496) itemoff 15704 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 106496 nr 90112 ram 1048576
		extent compression 0
	item 9 key (257 EXTENT_DATA 196608) itemoff 15651 itemsize 53
		extent data disk byte 13996032 nr 106496
		extent data offset 0 nr 106496 ram 106496
		extent compression 0
	item 10 key (257 EXTENT_DATA 303104) itemoff 15598 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 303104 nr 593920
	item 11 key (257 EXTENT_DATA 897024) itemoff 15545 itemsize 53
		extent data disk byte 14102528 nr 106496
		extent data offset 0 nr 106496 ram 106496
		extent compression 0
	item 12 key (257 EXTENT_DATA 1003520) itemoff 15492 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 1003520 nr 45056 ram 1048576
		extent compression 0
(...)

With this change, the above example will no longer cause allocation of new data
space nor change the sequentiality of the file extents, that is, defragment will
be effectless, leaving all extent items pointing to the extent starting at disk
byte 12845056.

In a 20Gb filesystem I had, mounted with the autodefrag option and 20 files of
400Mb each, initially consisting of a single prealloc extent of 400Mb, having
random writes happening at a low rate, lead to a total of over ~17Gb of data
space used, not far from eventually reaching an ENOSPC state.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:17 -04:00
Filipe Manana dec8ef9055 Btrfs: correctly flush data on defrag when compression is enabled
When the defrag flag BTRFS_DEFRAG_RANGE_START_IO is set and compression
enabled, we weren't flushing completely, as writing compressed extents
is a 2 steps process, one to compress the data and another one to write
the compressed data to disk.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:16 -04:00
Qu Wenruo d458b0540e btrfs: Cleanup the "_struct" suffix in btrfs_workequeue
Since the "_struct" suffix is mainly used for distinguish the differnt
btrfs_work between the original and the newly created one,
there is no need using the suffix since all btrfs_workers are changed
into btrfs_workqueue.

Also this patch fixed some codes whose code style is changed due to the
too long "_struct" suffix.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:16 -04:00
Qu Wenruo a046e9c88b btrfs: Cleanup the old btrfs_worker.
Since all the btrfs_worker is replaced with the newly created
btrfs_workqueue, the old codes can be easily remove.

Signed-off-by: Quwenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:15 -04:00
Qu Wenruo 0339ef2f42 btrfs: Replace fs_info->scrub_* workqueue with btrfs_workqueue.
Replace the fs_info->scrub_* with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:14 -04:00
Qu Wenruo fc97fab0ea btrfs: Replace fs_info->qgroup_rescan_worker workqueue with btrfs_workqueue.
Replace the fs_info->qgroup_rescan_worker with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:13 -04:00
Qu Wenruo 5b3bc44e2e btrfs: Replace fs_info->delayed_workers workqueue with btrfs_workqueue.
Replace the fs_info->delayed_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:12 -04:00
Qu Wenruo dc6e320998 btrfs: Replace fs_info->fixup_workers workqueue with btrfs_workqueue.
Replace the fs_info->fixup_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:12 -04:00
Qu Wenruo 736cfa15e8 btrfs: Replace fs_info->readahead_workers workqueue with btrfs_workqueue.
Replace the fs_info->readahead_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:11 -04:00
Qu Wenruo e66f0bb144 btrfs: Replace fs_info->cache_workers workqueue with btrfs_workqueue.
Replace the fs_info->cache_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:10 -04:00
Qu Wenruo d05a33ac26 btrfs: Replace fs_info->rmw_workers workqueue with btrfs_workqueue.
Replace the fs_info->rmw_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:09 -04:00
Qu Wenruo fccb5d86d8 btrfs: Replace fs_info->endio_* workqueue with btrfs_workqueue.
Replace the fs_info->endio_* workqueues with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:08 -04:00
Qu Wenruo a44903abe9 btrfs: Replace fs_info->flush_workers with btrfs_workqueue.
Replace the fs_info->submit_workers with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:07 -04:00
Qu Wenruo a8c93d4ef6 btrfs: Replace fs_info->submit_workers with btrfs_workqueue.
Much like the fs_info->workers, replace the fs_info->submit_workers
use the same btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:07 -04:00
Qu Wenruo afe3d24267 btrfs: Replace fs_info->delalloc_workers with btrfs_workqueue
Much like the fs_info->workers, replace the fs_info->delalloc_workers
use the same btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:06 -04:00
Qu Wenruo 5cdc7ad337 btrfs: Replace fs_info->workers with btrfs_workqueue.
Use the newly created btrfs_workqueue_struct to replace the original
fs_info->workers

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:05 -04:00
Qu Wenruo 0bd9289c28 btrfs: Add threshold workqueue based on kernel workqueue
The original btrfs_workers has thresholding functions to dynamically
create or destroy kthreads.

Though there is no such function in kernel workqueue because the worker
is not created manually, we can still use the workqueue_set_max_active
to simulated the behavior, mainly to achieve a better HDD performance by
setting a high threshold on submit_workers.
(Sadly, no resource can be saved)

So in this patch, extra workqueue pending counters are introduced to
dynamically change the max active of each btrfs_workqueue_struct, hoping
to restore the behavior of the original thresholding function.

Also, workqueue_set_max_active use a mutex to protect workqueue_struct,
which is not meant to be called too frequently, so a new interval
mechanism is applied, that will only call workqueue_set_max_active after
a count of work is queued. Hoping to balance both the random and
sequence performance on HDD.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:04 -04:00
Qu Wenruo 1ca08976ae btrfs: Add high priority workqueue support for btrfs_workqueue_struct
Add high priority function to btrfs_workqueue.

This is implemented by embedding a btrfs_workqueue into a
btrfs_workqueue and use some helper functions to differ the normal
priority wq and high priority wq.
So the high priority wq is completely independent from the normal
workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:03 -04:00
Qu Wenruo 08a9ff3264 btrfs: Added btrfs_workqueue_struct implemented ordered execution based on kernel workqueue
Use kernel workqueue to implement a new btrfs_workqueue_struct, which
has the ordering execution feature like the btrfs_worker.

The func is executed in a concurrency way, and the
ordred_func/ordered_free is executed in the sequence them are queued
after the corresponding func is done.

The new btrfs_workqueue works much like the original one, one workqueue
for normal work and a list for ordered work.
When a work is queued, ordered work will be added to the list and helper
function will be queued into the workqueue.
The helper function will execute a normal work and then check and execute as many
ordered work as possible in the sequence they were queued.

At this patch, high priority work queue or thresholding is not added yet.
The high priority feature and thresholding will be added in the following patches.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:03 -04:00
Qu Wenruo f5961d41d7 btrfs: Cleanup the unused struct async_sched.
The struct async_sched is not used by any codes and can be removed.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fusionio.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:02 -04:00
Liu Bo 644d1940ab Btrfs: skip search tree for REG files
It is really unnecessary to search tree again for @gen, @mode and @rdev
in the case of REG inodes' creation, as we've got btrfs_inode_item in sctx,
and @gen, @mode and @rdev can easily be fetched.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:01 -04:00
Miao Xie 7b2b70851f Btrfs: fix preallocate vs double nocow write
We can not release the reserved metadata space for the first write if we
find the write position is pre-allocated. Because the kernel might write
the data on the disk before we do the second write but after the can-nocow
check, if we release the space for the first write, we might fail to update
the metadata because of no space.

Fix this problem by end nocow write if there is dirty data in the range whose
space is pre-allocated.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:00 -04:00
Miao Xie c933956ddf Btrfs: fix wrong lock range and write size in check_can_nocow()
The write range may not be sector-aligned, for example:

       |--------|--------|	<- write range, sector-unaligned, size: 2blocks
  |--------|--------|--------|  <- correct lock range, size: 3blocks

But according to the old code, we used the size of write range to calculate
the lock range directly, not considered the offset, we would get a wrong lock
range:

       |--------|--------|	<- write range, sector-unaligned, size: 2blocks
  |--------|--------|		<- wrong lock range, size: 2blocks

And besides that, the old code also had the same problem when calculating
the real write size. Correct them.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:00 -04:00
David Sterba 9c9ca00bd3 btrfs: send: simplify allocation code in fs_path_ensure_buf
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:59 -04:00
David Sterba 1b2782c8ed btrfs: send: fix old buffer length in fs_path_ensure_buf
In "btrfs: send: lower memory requirements in common case" the code to
save the old_buf_len was incorrectly moved to a wrong place and broke
the original logic.

Reported-by: Filipe David Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Filipe David Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:58 -04:00
Filipe Manana 176840b3aa Btrfs: more efficient btrfs_drop_extent_cache
While droping extent map structures from the extent cache that cover our
target range, we would remove each extent map structure from the red black
tree and then add either 1 or 2 new extent map structures if the former
extent map covered sections outside our target range.

This change simply attempts to replace the existing extent map structure
with a new one that covers the subsection we're not interested in, instead
of doing a red black remove operation followed by an insertion operation.

The number of elements in an inode's extent map tree can get very high for large
files under random writes. For example, while running the following test:

    sysbench --test=fileio --file-num=1 --file-total-size=10G \
        --file-test-mode=rndrw --num-threads=32 --file-block-size=32768 \
        --max-requests=500000 --file-rw-ratio=2 [prepare|run]

I captured the following histogram capturing the number of extent_map items
in the red black tree while that test was running:

    Count: 122462
    Range:  1.000 - 172231.000; Mean: 96415.831; Median: 101855.000; Stddev: 49700.981
    Percentiles:  90th: 160120.000; 95th: 166335.000; 99th: 171070.000
       1.000 -    5.231:   452 |
       5.231 -  187.392:    87 |
     187.392 -  585.911:   206 |
     585.911 - 1827.438:   623 |
    1827.438 - 5695.245:  1962 #
    5695.245 - 17744.861:  6204 ####
   17744.861 - 55283.764: 21115 ############
   55283.764 - 172231.000: 91813 #####################################################

Benchmark:

    sysbench --test=fileio --file-num=1 --file-total-size=10G --file-test-mode=rndwr \
        --num-threads=64 --file-block-size=32768 --max-requests=0 --max-time=60 \
        --file-io-mode=sync --file-fsync-freq=0 [prepare|run]

Before this change: 122.1Mb/sec
After this change:  125.07Mb/sec
(averages of 5 test runs)

Test machine: quad core intel i5-3570K, 32Gb of ram, SSD

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:57 -04:00
Filipe Manana f2071b2155 Btrfs: more efficient split extent state insertion
When we split an extent state there's no need to start the rbtree search
from the root node - we can start it from the original extent state node,
since we would end up in its subtree if we do the search starting at the
root node anyway.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:57 -04:00
Filipe Manana cbc0e9287d Btrfs: remove unneeded field / smaller extent_map structure
We don't need to have an unsigned int field in the extent_map struct
to tell us whether the extent map is in the inode's extent_map tree or
not. We can use the rb_node struct field and the RB_CLEAR_NODE and
RB_EMPTY_NODE macros to achieve the same task.

This reduces sizeof(struct extent_map) from 152 bytes to 144 bytes (on a
64 bits system).

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:56 -04:00
Wang Shilong e84752d434 Btrfs: skip locking when searching commit root
We won't change commit root, skip locking dance with commit root
when walking backrefs, this can speed up btrfs send operations.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:55 -04:00
Wang Shilong 32a447896c Btrfs: wake up @scrub_pause_wait as much as we can
check if @scrubs_running=@scrubs_paused condition inside wait_event()
is not an atomic operation which means we may inc/dec @scrub_running/
paused at any time. Let's wake up @scrub_pause_wait as much as we can
to let commit transaction blocked less.

An example below:

Thread1				Thread2
|->scrub_blocked_if_needed()	|->scrub_pending_trans_workers_inc
  |->increase @scrub_paused
                                       |->increase @scrub_running
  |->wake up scrub_pause_wait list
                                       |->scrub blocked
                                       |->increase @scrub_paused

Thread3 is commiting transaction which is blocked at btrfs_scrub_pause().
So after Thread2 increase @scrub_paused, we meet the condition
@scrub_paused=@scrub_running, but transaction will be still blocked until
another calling to wake up @scrub_pause_wait.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:54 -04:00
Wang Shilong c0af8f0b1c Btrfs: cancel scrub on transaction abortion
If we fail to commit transaction, we'd better
cancel scrub operations.

Suggested-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:54 -04:00
Wang Shilong 12cf93728d Btrfs: device_replace: fix deadlock for nocow case
commit cb7ab02156 cause a following deadlock found by
xfstests,btrfs/011:

Thread1 is commiting transaction which is blocked at
btrfs_scrub_pause().

Thread2 is calling btrfs_file_aio_write() which has held
inode's @i_mutex and commit transaction(blocked because
Thread1 is committing transaction).

Thread3 is copy_nocow_page worker which will also try to
hold inode @i_mutex, so thread3 will wait Thread1 finished.

Thread4 is waiting pending workers finished which will wait
Thread3 finished. So the problem is like this:

Thread1--->Thread4--->Thread3--->Thread2---->Thread1

Deadlock happens! we fix it by letting Thread1 go firstly,
which means we won't block transaction commit while we are
waiting pending workers finished.

Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:53 -04:00
Wang Shilong 6cf7f77e6b Btrfs: fix a possible deadlock between scrub and transaction committing
btrfs_scrub_continue() will be called when cleaning up transaction.However,
this can only be called if btrfs_scrub_pause() is called before.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:52 -04:00
Sachin Kamat 886322e8e7 btrfs: Use PTR_ERR_OR_ZERO
PTR_RET is deprecated. Use PTR_ERR_OR_ZERO instead. While at it
also include missing err.h header.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:51 -04:00
Filipe Manana bf0d1f441d Btrfs: fix send issuing outdated paths for utimes, chown and chmod
When doing an incremental send, if we had a directory pending a move/rename
operation and none of its parents, except for the immediate parent, were
pending a move/rename, after processing the directory's references, we would
be issuing utimes, chown and chmod intructions against am outdated path - a
path which matched the one in the parent root.

This change also simplifies a bit the code that deals with building a path
for a directory which has a move/rename operation delayed.

Steps to reproduce:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b/c/d/e
    $ mkdir /mnt/btrfs/a/b/c/f
    $ chmod 0777 /mnt/btrfs/a/b/c/d/e
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ mv /mnt/btrfs/a/b/c/f /mnt/btrfs/a/b/f2
    $ mv /mnt/btrfs/a/b/c/d/e /mnt/btrfs/a/b/f2/e2
    $ mv /mnt/btrfs/a/b/c /mnt/btrfs/a/b/c2
    $ mv /mnt/btrfs/a/b/c2/d /mnt/btrfs/a/b/c2/d2
    $ chmod 0700 /mnt/btrfs/a/b/f2/e2
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umount /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:

    ERROR: chmod a/b/c/d/e failed. No such file or directory

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:51 -04:00
Filipe Manana 6baa4293af Btrfs: correctly determine if blocks are shared in btrfs_compare_trees
Just comparing the pointers (logical disk addresses) of the btree nodes is
not completely bullet proof, we have to check if their generation numbers
match too.

It is guaranteed that a COW operation will result in a block with a different
logical disk address than the original block's address, but over time we can
reuse that former logical disk address.

For example, creating a 2Gb filesystem on a loop device, and having a script
running in a loop always updating the access timestamp of a file, resulted in
the same logical disk address being reused for the same fs btree block in about
only 4 minutes.

This could make us skip entire subtrees when doing an incremental send (which
is currently the only user of btrfs_compare_trees). However the odds of getting
2 blocks at the same tree level, with the same logical disk address, equal first
slot keys and different generations, should hopefully be very low.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:50 -04:00
Filipe Manana 9dc442143b Btrfs: fix send attempting to rmdir non-empty directories
The incremental send algorithm assumed that it was possible to issue
a directory remove (rmdir) if the the inode number it was currently
processing was greater than (or equal) to any inode that referenced
the directory's inode. This wasn't a valid assumption because any such
inode might be a child directory that is pending a move/rename operation,
because it was moved into a directory that has a higher inode number and
was moved/renamed too - in other words, the case the following commit
addressed:

    9f03740a95
    (Btrfs: fix infinite path build loops in incremental send)

This made an incremental send issue an rmdir operation before the
target directory was actually empty, which made btrfs receive fail.
Therefore it needs to wait for all pending child directory inodes to
be moved/renamed before sending an rmdir operation.

Simple steps to reproduce this issue:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b/c/x
    $ mkdir /mnt/btrfs/a/b/y
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ mv /mnt/btrfs/a/b/y /mnt/btrfs/a/b/YY
    $ mv /mnt/btrfs/a/b/c/x /mnt/btrfs/a/b/YY
    $ rmdir /mnt/btrfs/a/b/c
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umount /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:

    ERROR: rmdir o259-6-0 failed. Directory not empty

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:49 -04:00
Filipe Manana 29d6d30f5c Btrfs: send, don't send rmdir for same target multiple times
When doing an incremental send, if we delete a directory that has N > 1
hardlinks for the same file and that file has the highest inode number
inside the directory contents, an incremental send would send N times an
rmdir operation against the directory. This made the btrfs receive command
fail on the second rmdir instruction, as the target directory didn't exist
anymore.

Steps to reproduce the issue:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b/c
    $ echo 'ola mundo' > /mnt/btrfs/a/b/c/foo.txt
    $ ln /mnt/btrfs/a/b/c/foo.txt /mnt/btrfs/a/b/c/bar.txt
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ rm -f /mnt/btrfs/a/b/c/foo.txt
    $ rm -f /mnt/btrfs/a/b/c/bar.txt
    $ rmdir /mnt/btrfs/a/b/c
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umount /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:

    ERROR: rmdir o259-6-0 failed. No such file or directory

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:48 -04:00
Filipe Manana 2b863a135f Btrfs: incremental send, fix invalid path after dir rename
This fixes yet one more case not caught by the commit titled:

   Btrfs: fix infinite path build loops in incremental send

In this case, even before the initial full send, we have a directory
which is a child of a directory with a higher inode number. Then we
perform the initial send, and after we rename both the child and the
parent, without moving them around. After doing these 2 renames, an
incremental send sent a rename instruction for the child directory
which contained an invalid "from" path (referenced the parent's old
name, not the new one), which made the btrfs receive command fail.

Steps to reproduce:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b
    $ mkdir /mnt/btrfs/d
    $ mkdir /mnt/btrfs/a/b/c
    $ mv /mnt/btrfs/d /mnt/btrfs/a/b/c
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ mv /mnt/btrfs/a/b/c /mnt/btrfs/a/b/x
    $ mv /mnt/btrfs/a/b/x/d /mnt/btrfs/a/b/x/y
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umout /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:
  "ERROR: rename a/b/c/d -> a/b/x/y failed. No such file or directory"

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:48 -04:00
Filipe Manana 12870f1c9b Btrfs: don't insert useless holes when punching beyond the inode's size
If we punch beyond the size of an inode, we'll correctly remove any prealloc extents,
but we'll also insert file extent items representing holes (disk bytenr == 0) that start
with a key offset that lies beyond the inode's size and are not contiguous with the last
file extent item.

Example:

  $XFS_IO_PROG -f -c "truncate 118811" $SCRATCH_MNT/foo
  $XFS_IO_PROG -c "fpunch 582007 864596" $SCRATCH_MNT/foo
  $XFS_IO_PROG -c "pwrite -S 0x0d -b 39987 92267 39987" $SCRATCH_MNT/foo

btrfs-debug-tree output:

  item 4 key (257 INODE_ITEM 0) itemoff 15885 itemsize 160
	inode generation 6 transid 6 size 132254 block group 0 mode 100600 links 1
  item 5 key (257 INODE_REF 256) itemoff 15872 itemsize 13
	inode ref index 2 namelen 3 name: foo
  item 6 key (257 EXTENT_DATA 0) itemoff 15819 itemsize 53
	extent data disk byte 0 nr 0 gen 6
	extent data offset 0 nr 90112 ram 122880
	extent compression 0
  item 7 key (257 EXTENT_DATA 90112) itemoff 15766 itemsize 53
	extent data disk byte 12845056 nr 4096 gen 6
	extent data offset 0 nr 45056 ram 45056
	extent compression 2
  item 8 key (257 EXTENT_DATA 585728) itemoff 15713 itemsize 53
	extent data disk byte 0 nr 0 gen 6
	extent data offset 0 nr 860160 ram 860160
	extent compression 0

The last extent item, which represents a hole, is useless as it lies beyond the inode's
size.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:47 -04:00
Filipe Manana 85fdfdf611 Btrfs: cleanup delayed-ref.c:find_ref_head()
The argument last wasn't used, all callers supplied a NULL value
for it. Also removed unnecessary intermediate storage of the result
of key comparisons.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:46 -04:00
Filipe Manana 6103fb43fb Btrfs: remove unnecessary ref heads rb tree search
When we didn't find the exact ref head we were looking for, if
return_bigger != 0 we set a new search key to match either the
next node after the last one we found or the first one in the
ref heads rb tree, and then did another full tree search. For both
cases this ended up being pointless as we would end up returning
an entry we already had before repeating the search.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:46 -04:00
Justin Maggard 2c6a92b009 btrfs: wake up transaction thread upon remount
Now that we can adjust the commit interval with a remount, we need
to wake up the transaction thread or else he will continue to sleep
until the previous transaction interval has elapsed before waking
up.  So, if we go from a large commit interval to something smaller,
the transaction thread will not wake up until the large interval has
expired.  This also causes the cleaner thread to stay sleeping, since
it gets woken up by the transaction thread.

Fix it by simply waking up the transaction thread during a remount.

Signed-off-by: Justin Maggard <jmaggard10@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:45 -04:00
Miao Xie 50471a388c Btrfs: stop joining the log transaction if sync log fails
If the log sync fails, there is something wrong in the log tree, we
should not continue to join the log transaction and log the metadata.
What we should do is to do a full commit.

This patch fixes this problem by setting ->last_trans_log_full_commit
to the current transaction id, it will tell the tasks not to join
the log transaction, and do a full commit.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:44 -04:00
Miao Xie d1433debe7 Btrfs: just wait or commit our own log sub-transaction
We might commit the log sub-transaction which didn't contain the metadata we
logged. It was because we didn't record the log transid and just select
the current log sub-transaction to commit, but the right one might be
committed by the other task already. Actually, we needn't do anything
and it is safe that we go back directly in this case.

This patch improves the log sync by the above idea. We record the transid
of the log sub-transaction in which we log the metadata, and the transid
of the log sub-transaction we have committed. If the committed transid
is >= the transid we record when logging the metadata, we just go back.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:43 -04:00
Miao Xie 8b050d350c Btrfs: fix skipped error handle when log sync failed
It is possible that many tasks sync the log tree at the same time, but
only one task can do the sync work, the others will wait for it. But those
wait tasks didn't get the result of the log sync, and returned 0 when they
ended the wait. It caused those tasks skipped the error handle, and the
serious problem was they told the users the file sync succeeded but in
fact they failed.

This patch fixes this problem by introducing a log context structure,
we insert it into the a global list. When the sync fails, we will set
the error number of every log context in the list, then the waiting tasks
get the error number of the log context and handle the error if need.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:43 -04:00
Miao Xie bb14a59b61 Btrfs: use signed integer instead of unsigned long integer for log transid
The log trans id is initialized to be 0 every time we create a log tree,
and the log tree need be re-created after a new transaction is started,
it means the log trans id is unlikely to be a huge number, so we can use
signed integer instead of unsigned long integer to save a bit space.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:42 -04:00
Miao Xie 7483e1a446 Btrfs: remove unnecessary memory barrier in btrfs_sync_log()
Mutex unlock implies certain memory barriers to make sure all the memory
operation completes before the unlock, and the next mutex lock implies memory
barriers to make sure the all the memory happens after the lock. So it is
a full memory barrier(smp_mb), we needn't add memory barriers. Remove them.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:41 -04:00
Miao Xie e87ac13687 Btrfs: don't start the log transaction if the log tree init fails
The old code would start the log transaction even the log tree init
failed, it was unnecessary. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:40 -04:00
Miao Xie 48cab2e071 Btrfs: fix the skipped transaction commit during the file sync
We may abort the wait earlier if ->last_trans_log_full_commit was set to
the current transaction id, at this case, we need commit the current
transaction instead of the log sub-transaction. But the current code
didn't tell the caller to do it (return 0, not -EAGAIN). Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:40 -04:00
Miao Xie 5c902ba622 Btrfs: use ACCESS_ONCE to prevent the optimize accesses to ->last_trans_log_full_commit
->last_trans_log_full_commit may be changed by the other tasks without lock,
so we need prevent the compiler from the optimize access just like
	tmp = fs_info->last_trans_log_full_commit
	if (tmp == ...)
		...

	<do something>

	if (tmp == ...)
		...

In fact, we need get the new value of ->last_trans_log_full_commit during
the second access. Fix it by ACCESS_ONCE().

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:39 -04:00
Liu Bo 7813b3db0a Btrfs: avoid warning bomb of btrfs_invalidate_inodes
So after transaction is aborted, we need to cleanup inode resources by
calling btrfs_invalidate_inodes(), and btrfs_invalidate_inodes() hopes
roots' refs to be zero in old times and sets a WARN_ON(), however, this
is not always true within cleaning up transaction, so we get to detect
transaction abortion and not warn at all.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:38 -04:00
Liu Bo 2a85d9cac1 Btrfs: fix possible deadlock in btrfs_cleanup_transaction
[13654.480669] ======================================================
[13654.480905] [ INFO: possible circular locking dependency detected ]
[13654.481003] 3.12.0+ #4 Tainted: G        W  O
[13654.481060] -------------------------------------------------------
[13654.481060] btrfs-transacti/9347 is trying to acquire lock:
[13654.481060]  (&(&root->ordered_extent_lock)->rlock){+.+...}, at: [<ffffffffa02d30a1>] btrfs_cleanup_transaction+0x271/0x570 [btrfs]
[13654.481060] but task is already holding lock:
[13654.481060]  (&(&fs_info->ordered_root_lock)->rlock){+.+...}, at: [<ffffffffa02d3015>] btrfs_cleanup_transaction+0x1e5/0x570 [btrfs]
[13654.481060] which lock already depends on the new lock.

[13654.481060] the existing dependency chain (in reverse order) is:
[13654.481060] -> #1 (&(&fs_info->ordered_root_lock)->rlock){+.+...}:
[13654.481060]        [<ffffffff810c4103>] lock_acquire+0x93/0x130
[13654.481060]        [<ffffffff81689991>] _raw_spin_lock+0x41/0x50
[13654.481060]        [<ffffffffa02f011b>] __btrfs_add_ordered_extent+0x39b/0x450 [btrfs]
[13654.481060]        [<ffffffffa02f0202>] btrfs_add_ordered_extent+0x32/0x40 [btrfs]
[13654.481060]        [<ffffffffa02df6aa>] run_delalloc_nocow+0x78a/0x9d0 [btrfs]
[13654.481060]        [<ffffffffa02dfc0d>] run_delalloc_range+0x31d/0x390 [btrfs]
[13654.481060]        [<ffffffffa02f7c00>] __extent_writepage+0x310/0x780 [btrfs]
[13654.481060]        [<ffffffffa02f830a>] extent_write_cache_pages.isra.29.constprop.48+0x29a/0x410 [btrfs]
[13654.481060]        [<ffffffffa02f879d>] extent_writepages+0x4d/0x70 [btrfs]
[13654.481060]        [<ffffffffa02d9f68>] btrfs_writepages+0x28/0x30 [btrfs]
[13654.481060]        [<ffffffff8114be91>] do_writepages+0x21/0x50
[13654.481060]        [<ffffffff81140d49>] __filemap_fdatawrite_range+0x59/0x60
[13654.481060]        [<ffffffff81140e13>] filemap_fdatawrite_range+0x13/0x20
[13654.481060]        [<ffffffffa02f1db9>] btrfs_wait_ordered_range+0x49/0x140 [btrfs]
[13654.481060]        [<ffffffffa0318fe2>] __btrfs_write_out_cache+0x682/0x8b0 [btrfs]
[13654.481060]        [<ffffffffa031952d>] btrfs_write_out_cache+0x8d/0xe0 [btrfs]
[13654.481060]        [<ffffffffa02c7083>] btrfs_write_dirty_block_groups+0x593/0x680 [btrfs]
[13654.481060]        [<ffffffffa0345307>] commit_cowonly_roots+0x14b/0x20d [btrfs]
[13654.481060]        [<ffffffffa02d7c1a>] btrfs_commit_transaction+0x43a/0x9d0 [btrfs]
[13654.481060]        [<ffffffffa030061a>] btrfs_create_uuid_tree+0x5a/0x100 [btrfs]
[13654.481060]        [<ffffffffa02d5a8a>] open_ctree+0x21da/0x2210 [btrfs]
[13654.481060]        [<ffffffffa02ab6fe>] btrfs_mount+0x68e/0x870 [btrfs]
[13654.481060]        [<ffffffff811b2409>] mount_fs+0x39/0x1b0
[13654.481060]        [<ffffffff811cd653>] vfs_kern_mount+0x63/0xf0
[13654.481060]        [<ffffffff811cfcce>] do_mount+0x23e/0xa90
[13654.481060]        [<ffffffff811d05a3>] SyS_mount+0x83/0xc0
[13654.481060]        [<ffffffff81692b52>] system_call_fastpath+0x16/0x1b
[13654.481060] -> #0 (&(&root->ordered_extent_lock)->rlock){+.+...}:
[13654.481060]        [<ffffffff810c340a>] __lock_acquire+0x150a/0x1a70
[13654.481060]        [<ffffffff810c4103>] lock_acquire+0x93/0x130
[13654.481060]        [<ffffffff81689991>] _raw_spin_lock+0x41/0x50
[13654.481060]        [<ffffffffa02d30a1>] btrfs_cleanup_transaction+0x271/0x570 [btrfs]
[13654.481060]        [<ffffffffa02d35ce>] transaction_kthread+0x22e/0x270 [btrfs]
[13654.481060]        [<ffffffff81079efa>] kthread+0xea/0xf0
[13654.481060]        [<ffffffff81692aac>] ret_from_fork+0x7c/0xb0
[13654.481060] other info that might help us debug this:

[13654.481060]  Possible unsafe locking scenario:

[13654.481060]        CPU0                    CPU1
[13654.481060]        ----                    ----
[13654.481060]   lock(&(&fs_info->ordered_root_lock)->rlock);
[13654.481060]				 lock(&(&root->ordered_extent_lock)->rlock);
[13654.481060]				 lock(&(&fs_info->ordered_root_lock)->rlock);
[13654.481060]   lock(&(&root->ordered_extent_lock)->rlock);
[13654.481060]
 *** DEADLOCK ***
[...]

======================================================

btrfs_destroy_all_ordered_extents()
gets &fs_info->ordered_root_lock __BEFORE__ acquiring &root->ordered_extent_lock,
while btrfs_[add,remove]_ordered_extent()
acquires &fs_info->ordered_root_lock __AFTER__ getting &root->ordered_extent_lock.

This patch fixes the above problem.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:37 -04:00
Filipe David Borba Manana d5f375270a Btrfs: faster/more efficient insertion of file extent items
This is an extension to my previous commit titled:

  "Btrfs: faster file extent item replace operations"
  (hash 1acae57b16)

Instead of inserting the new file extent item if we deleted existing
file extent items covering our target file range, also allow to insert
the new file extent item if we didn't find any existing items to delete
and replace_extent != 0, since in this case our caller would do another
tree search to insert the new file extent item anyway, therefore just
combine the two tree searches into a single one, saving cpu time, reducing
lock contention and reducing btree node/leaf COW operations.

This covers the case where applications keep doing tail append writes to
files, which for example is the case of Apache CouchDB (its database and
view index files are always open with O_APPEND).

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:37 -04:00
Stanislaw Gruszka 51b98effa4 btrfs: always choose work from prio_head first
In case we do not refill, we can overwrite cur pointer from prio_head
by one from not prioritized head, what looks as something that was
not intended.

This change make we always take works from prio_head first until it's
not empty.

Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:36 -04:00
Wang Shilong dcfd5ad2fc Revert "Btrfs: remove transaction from btrfs send"
This reverts commit 41ce9970a8.
Previously i was thinking we can use readonly root's commit root
safely while it is not true, readonly root may be cowed with the
following cases.

1.snapshot send root will cow source root.
2.balance,device operations will also cow readonly send root
to relocate.

So i have two ideas to make us safe to use commit root.

-->approach 1:
make it protected by transaction and end transaction properly and we research
next item from root node(see btrfs_search_slot_for_read()).

-->approach 2:
add another counter to local root structure to sync snapshot with send.
and add a global counter to sync send with exclusive device operations.

So with approach 2, send can use commit root safely, because we make sure
send root can not be cowed during send. Unfortunately, it make codes *ugly*
and more complex to maintain.

To make snapshot and send exclusively, device operations and send operation
exclusively with each other is a little confusing for common users.

So why not drop into previous way.

Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:35 -04:00
Wang Shilong bcbba5e659 Btrfs: skip readonly root for snapshot-aware defragment
Btrfs send is assuming readonly root won't change, let's skip readonly root.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:34 -04:00
Wang Shilong 850a8cdffe Btrfs: switch to btrfs_previous_extent_item()
Since we have introduced btrfs_previous_extent_item() to search previous
extent item, just switch into it.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:54 -04:00
Hidetoshi Seto f88ba6a2a4 Btrfs: skip submitting barrier for missing device
I got an error on v3.13:
 BTRFS error (device sdf1) in write_all_supers:3378: errno=-5 IO failure (errors while submitting device barriers.)

how to reproduce:
  > mkfs.btrfs -f -d raid1 /dev/sdf1 /dev/sdf2
  > wipefs -a /dev/sdf2
  > mount -o degraded /dev/sdf1 /mnt
  > btrfs balance start -f -sconvert=single -mconvert=single -dconvert=single /mnt

The reason of the error is that barrier_all_devices() failed to submit
barrier to the missing device.  However it is clear that we cannot do
anything on missing device, and also it is not necessary to care chunks
on the missing device.

This patch stops sending/waiting barrier if device is missing.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:53 -04:00
Josef Bacik 29bce2f399 Btrfs: unlock extent and pages on error in cow_file_range
When I converted the BUG_ON() for the free_space_cache_inode in cow_file_range I
made it so we just return an error instead of unlocking all of our various
stuff.  This is a mistake and causes us to hang when we run into this.  This
patch fixes this problem.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:53 -04:00
Josef Bacik c581afc8db Btrfs: balance delayed inode updates
While trying to reproduce a delayed ref problem I noticed the box kept falling
over using all 80gb of my ram with btrfs_inode's and btrfs_delayed_node's.
Turns out this is because we only throttle delayed inode updates in
btrfs_dirty_inode, which doesn't actually get called that often, especially when
all you are doing is creating a bunch of files.  So balance delayed inode
updates everytime we create a new inode.  With this patch we no longer use up
all of our ram with delayed inode updates.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:52 -04:00
David Sterba 1bae30982b btrfs: add simple debugfs interface
Help during debugging to export various interesting infromation and
tunables without the need of extra mount options or ioctls.

Usage:
* declare your variable in sysfs.h, and include where you need it
* define the variable in sysfs.c and make it visible via
  debugfs_create_TYPE

Depends on CONFIG_DEBUG_FS.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:51 -04:00
David Sterba ace0105076 btrfs: send: lower memory requirements in common case
The fs_path structure uses an inline buffer and falls back to a chain of
allocations, but vmalloc is not necessary because PATH_MAX fits into
PAGE_SIZE.

The size of fs_path has been reduced to 256 bytes from PAGE_SIZE,
usually 4k. Experimental measurements show that most paths on a single
filesystem do not exceed 200 bytes, and these get stored into the inline
buffer directly, which is now 230 bytes. Longer paths are kmalloced when
needed.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:50 -04:00
Filipe David Borba Manana dff6d0adbe Btrfs: make some tree searches in send.c more efficient
We have this pattern where we do search for a contiguous group of
items in a tree and everytime we find an item, we process it, then
we release our path, increment the offset of the search key, do
another full tree search and repeat these steps until a tree search
can't find more items we're interested in.

Instead of doing these full tree searches after processing each item,
just process the next item/slot in our leaf and don't release the path.
Since all these trees are read only and we always use the commit root
for a search and skip node/leaf locks, we're not affecting concurrency
on the trees.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:49 -04:00
Filipe David Borba Manana a0859c0998 Btrfs: use right extent item position in send when finding extent clones
This was a leftover from the commit:

   74dd17fbe3
   (Btrfs: fix btrfs send for inline items and compression)

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:48 -04:00
David Sterba 57fb8910c2 btrfs: send: remove BUG_ON from name_cache_delete
If cleaning the name cache fails, we could try to proceed at the cost of
some memory leak. This is not expected to happen often.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:48 -04:00
David Sterba 4d1a63b21b btrfs: send: remove BUG from process_all_refs
There are only 2 static callers, the BUG would normally be never
reached, but let's be nice.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:47 -04:00
David Sterba 1f5a7ff999 btrfs: send: squeeze bitfilelds in fs_path
We know that buf_len is at most PATH_MAX, 4k, and can merge it with the
reversed member. This saves 3 bytes in favor of inline_buf.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:46 -04:00
David Sterba e25a812206 btrfs: send: remove virtual_mem member from fs_path
We don't need to keep track of that, it's available via is_vmalloc_addr.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:45 -04:00
David Sterba b23ab57d48 btrfs: send: remove prepared member from fs_path
The member is used only to return value back from
fs_path_prepare_for_add, we can do it locally and save 8 bytes for the
inline_buf path.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:44 -04:00
David Sterba 64792f2535 btrfs: send: replace check with an assert in gen_unique_name
The buffer passed to snprintf can hold the fully expanded format string,
64 = 3x largest ULL + 3x char + trailing null.  I don't think that removing the
check entirely is a good idea, hence the ASSERT.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:44 -04:00
Filipe David Borba Manana 5ed7f9ff15 Btrfs: more send support for parent/child dir relationship inversion
The commit titled "Btrfs: fix infinite path build loops in incremental send"
didn't cover a particular case where the parent-child relationship inversion
of directories doesn't imply a rename of the new parent directory. This was
due to a simple logic mistake, a logical and instead of a logical or.

Steps to reproduce:

  $ mkfs.btrfs -f /dev/sdb3
  $ mount /dev/sdb3 /mnt/btrfs
  $ mkdir -p /mnt/btrfs/a/b/bar1/bar2/bar3/bar4
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap1
  $ mv /mnt/btrfs/a/b/bar1/bar2/bar3/bar4 /mnt/btrfs/a/b/k44
  $ mv /mnt/btrfs/a/b/bar1/bar2/bar3 /mnt/btrfs/a/b/k44
  $ mv /mnt/btrfs/a/b/bar1/bar2 /mnt/btrfs/a/b/k44/bar3
  $ mv /mnt/btrfs/a/b/bar1 /mnt/btrfs/a/b/k44/bar3/bar2/k11
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap2
  $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 > /tmp/incremental.send

A patch to update the test btrfs/030 from xfstests, so that it covers
this case, will be submitted soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:43 -04:00
Filipe David Borba Manana 03cb4fb9d8 Btrfs: fix send dealing with file renames and directory moves
This fixes a case that the commit titled:

   Btrfs: fix infinite path build loops in incremental send

didn't cover. If the parent-child relationship between 2 directories
is inverted, both get renamed, and the former parent has a file that
got renamed too (but remains a child of that directory), the incremental
send operation would use the file's old path after sending an unlink
operation for that old path, causing receive to fail on future operations
like changing owner, permissions or utimes of the corresponding inode.

This is not a regression from the commit mentioned before, as without
that commit we would fall into the issues that commit fixed, so it's
just one case that wasn't covered before.

Simple steps to reproduce this issue are:

      $ mkfs.btrfs -f /dev/sdb3
      $ mount /dev/sdb3 /mnt/btrfs
      $ mkdir -p /mnt/btrfs/a/b/c/d
      $ touch /mnt/btrfs/a/b/c/d/file
      $ mkdir -p /mnt/btrfs/a/b/x
      $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap1
      $ mv /mnt/btrfs/a/b/x /mnt/btrfs/a/b/c/x2
      $ mv /mnt/btrfs/a/b/c/d /mnt/btrfs/a/b/c/x2/d2
      $ mv /mnt/btrfs/a/b/c/x2/d2/file /mnt/btrfs/a/b/c/x2/d2/file2
      $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap2
      $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 > /tmp/incremental.send

A patch to update the test btrfs/030 from xfstests, so that it covers
this case, will be submitted soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:42 -04:00
Wang Shilong 98cfee2143 Btrfs: only add roots if necessary in find_parent_nodes()
find_all_leafs() dosen't need add all roots actually, add roots only
if we need, this can avoid unnecessary ulist dance.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:41 -04:00
Hugo Mills abccd00f8a btrfs: Fix 32/64-bit problem with BTRFS_SET_RECEIVED_SUBVOL ioctl
The structure for BTRFS_SET_RECEIVED_IOCTL packs differently on 32-bit
and 64-bit systems. This means that it is impossible to use btrfs
receive on a system with a 64-bit kernel and 32-bit userspace, because
the structure size (and hence the ioctl number) is different.

This patch adds a compatibility structure and ioctl to deal with the
above case.

Signed-off-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:40 -04:00
Filipe David Borba Manana d86477b303 Btrfs: add missing error check in incremental send
Function wait_for_parent_move() returns negative value if an error
happened, 0 if we don't need to wait for the parent's move, and
1 if the wait is needed.
Before this change an error return value was being treated like the
return value 1, which was not correct.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:40 -04:00