Currently we disallow reflink and dedupe if the two files aren't on the same vfsmount. However we really only need to disallow it if they're not on the same super block. It is very common for btrfs to have a main subvolume that is mounted and then different subvolumes mounted at different locations. It's allowed to reflink between these volumes, but the vfsmount check disallows this. Instead fix dedupe to check for the same superblock, and simply remove the vfsmount check for reflink as it already does the superblock check. Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx> Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Josef Bacik <josef@xxxxxxxxxxxxxx> --- fs/ioctl.c | 4 ---- fs/remap_range.c | 7 +------ 2 files changed, 1 insertion(+), 10 deletions(-) diff --git a/fs/ioctl.c b/fs/ioctl.c index 1ed097e94af2..090bf47606ab 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -236,9 +236,6 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, if (!src_file.file) return -EBADF; - ret = -EXDEV; - if (src_file.file->f_path.mnt != dst_file->f_path.mnt) - goto fdput; cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff, olen, 0); if (cloned < 0) @@ -247,7 +244,6 @@ static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd, ret = -EINVAL; else ret = 0; -fdput: fdput(src_file); return ret; } diff --git a/fs/remap_range.c b/fs/remap_range.c index 231159682907..bc5fb006dc79 100644 --- a/fs/remap_range.c +++ b/fs/remap_range.c @@ -362,11 +362,6 @@ loff_t do_clone_file_range(struct file *file_in, loff_t pos_in, WARN_ON_ONCE(remap_flags & REMAP_FILE_DEDUP); - /* - * FICLONE/FICLONERANGE ioctls enforce that src and dest files are on - * the same mount. Practically, they only need to be on the same file - * system. - */ if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb) return -EXDEV; @@ -458,7 +453,7 @@ loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos, goto out_drop_write; ret = -EXDEV; - if (src_file->f_path.mnt != dst_file->f_path.mnt) + if (file_inode(src_file)->i_sb != file_inode(dst_file)->i_sb) goto out_drop_write; ret = -EISDIR; -- 2.26.3
