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>
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
...
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>
