Btrfs: Improve FL_KEEP_SIZE handling in fallocate
- We call inode_size_ok() only if FL_KEEP_SIZE isn't specified.
- As an optimisation we can skip the call if (off + len)
isn't greater than the current size of the file. This operation
is called under the lock so the less work we do, the better.
- If we call inode_size_ok() pass to it the correct value rather
than a more conservative estimation.
Signed-off-by: Davide Italiano <dccitaliano@gmail.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>
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 15a09cb..7af1abd 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2682,9 +2682,12 @@
return ret;
inode_lock(inode);
- ret = inode_newsize_ok(inode, alloc_end);
- if (ret)
- goto out;
+
+ if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + len > inode->i_size) {
+ ret = inode_newsize_ok(inode, offset + len);
+ if (ret)
+ goto out;
+ }
/*
* TODO: Move these two operations after we have checked