[PATCH Version-2 03/12] VFS permit cross device vfs_copy_file_range

[<andros@netapp.com>]

From: Andy Adamson <andros@rhel7-2-ga-3.androsad.fake>

NFSv4.2 inter server to server copy always copies across devices.

Note: both btrfs and nfs have EXDEV checks in their
copy_file_range functions.

Signed-off-by: Andy Adamson <andros@netapp.com>
---
 fs/read_write.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/fs/read_write.c b/fs/read_write.c
index 1cbab4e..a6d3350 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -1483,7 +1483,6 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
 			    size_t len, unsigned int flags)
 {
 	struct inode *inode_in = file_inode(file_in);
-	struct inode *inode_out = file_inode(file_out);
 	ssize_t ret;
 
 	if (flags != 0)
@@ -1505,10 +1504,6 @@ ssize_t vfs_copy_file_range(struct file *file_in, loff_t pos_in,
 	    (file_out->f_flags & O_APPEND))
 		return -EBADF;
 
-	/* this could be relaxed once a method supports cross-fs copies */
-	if (inode_in->i_sb != inode_out->i_sb)
-		return -EXDEV;
-
 	if (len == 0)
 		return 0;
 
-- 
1.8.3.1