[PATCH v2 3/4] cifs: remove redundant size-update block in cifs_remap_file_range()

[Frank Sorenson <sorenson@redhat.com>]

cifs_remap_file_range() acquires i_rwsem on both inodes via
lock_two_nondirectories() before calling smb2_duplicate_extents().
cifs_setsize() (called inside smb2_duplicate_extents() when the clone
extends the file) therefore already runs under the lock, meaning the
fscache_resize_cookie() added to cifs_setsize() by commit fa724e235cfd
("cifs: add fscache_resize_cookie() to cifs_setsize()") is correctly
serialised for this path without further changes.

That same commit made the caller-side block:

    if (rc == 0 && new_size > i_size) {
        truncate_setsize(target_inode, new_size);
        fscache_resize_cookie(cifs_inode_cookie(target_inode), new_size);
    }

redundant: smb2_duplicate_extents() already performs the full size update
via cifs_setsize() when the operation extends the file.  Remove the
now-dead block.

Signed-off-by: Frank Sorenson <sorenson@redhat.com>
Reviewed-by: Huiwen He <hehuiwen@kylinos.cn>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
---
 fs/smb/client/cifsfs.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c
index 1788d93a2522..1060ac5f9fff 100644
--- a/fs/smb/client/cifsfs.c
+++ b/fs/smb/client/cifsfs.c
@@ -1464,11 +1464,7 @@ static loff_t cifs_remap_file_range(struct file *src_file, loff_t off,
 	if (target_tcon->ses->server->ops->duplicate_extents) {
 		rc = target_tcon->ses->server->ops->duplicate_extents(xid,
 			smb_file_src, smb_file_target, off, len, destoff);
-		if (rc == 0 && new_size > i_size) {
-			truncate_setsize(target_inode, new_size);
-			fscache_resize_cookie(cifs_inode_cookie(target_inode),
-					      new_size);
-		} else if (rc == -EOPNOTSUPP) {
+		if (rc == -EOPNOTSUPP) {
 			/*
 			 * copy_file_range syscall man page indicates EINVAL
 			 * is returned e.g when "fd_in and fd_out refer to the
-- 
2.55.0