iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

btrfs: send: update comment at find_extent_clone()

Browse Source 
We have this unclear comment at find_extent_clone() about extents starting
at a file offset greater than or equals to the i_size of the inode. It's
not really informative and it's misleading, since it mentions the author
found such extents with snapshots and large files.

Such extents are a result of fallocate with FALLOC_FL_KEEP_SIZE and there
is no relation to snapshots or large files (all write paths update the
i_size before inserting a new file extent item). So update the comment to
be precise about it and why we don't bother looking for clone sources in
that case.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Filipe Manana 2022-11-01 16:15:42 +00:00 committed by David Sterba
parent 61ce908a3c
commit d3f41317f0
1 changed files with 7 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
fs/btrfs/send.c
View File

@ -1365,14 +1365,14 @@ static int find_extent_clone(struct send_ctx *sctx,
int compressed;
u32 i;
if (data_offset >= ino_size) {
/*
* There may be extents that lie behind the file's size.
* I at least had this in combination with snapshotting while
* writing large files.
* With fallocate we can get prealloc extents beyond the inode's i_size,
* so we don't do anything here because clone operations can not clone
* to a range beyond i_size without increasing the i_size of the
* destination inode.
*/
if (data_offset >= ino_size)
return 0;
}
fi = btrfs_item_ptr(eb, path->slots[0], struct btrfs_file_extent_item);
extent_type = btrfs_file_extent_type(eb, fi);