From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Don't bother calling the filesystem for a zero-length dedupe request; we can return zero and exit. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> --- fs/read_write.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/read_write.c b/fs/read_write.c index f7b728d4972f..3ff90b3315fb 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -1975,6 +1975,11 @@ int vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, if (!dst_file->f_op->dedupe_file_range) goto out_drop_write; + if (len == 0) { + ret = 0; + goto out_drop_write; + } + ret = dst_file->f_op->dedupe_file_range(src_file, src_pos, dst_file, dst_pos, len); out_drop_write: