smb: cilent: set reparse mount points as automounts

By doing so we can selectively mark those submounts as 'noserverino'
rather than whole mount and thus avoiding inode collisions in them.

Consider a "test" SMB share that has two mounted NTFS volumes
(vol0 & vol1) inside it.

* Before patch

$ mount.cifs //srv/test /mnt/1 -o ...,serverino
$ ls -li /mnt/1/vol0
total 1
281474976710693 drwxr-xr-x 2 root root 0 Jul 15 00:23 $RECYCLE.BIN
281474976710696 drwxr-xr-x 2 root root 0 Jul 18 18:23 System Volume...
281474976710699 -rwxr-xr-x 1 root root 0 Aug 14 21:53 f0
281474976710700 -rwxr-xr-x 1 root root 0 Aug 15 18:52 f2
281474976710698 drwxr-xr-x 2 root root 0 Aug 12 19:39 foo
281474976710692 -rwxr-xr-x 1 root root 5 Aug  4 21:18 vol0_f0.txt
$ ls -li /mnt/1/vol1
total 0
281474976710693 drwxr-xr-x 2 root root 0 Jul 15 00:23 $RECYCLE.BIN
281474976710696 drwxr-xr-x 2 root root 0 Jul 18 18:23 System Volume...
281474976710698 drwxr-xr-x 2 root root 0 Aug 12 19:39 bar
281474976710699 -rwxr-xr-x 1 root root 0 Aug 14 22:03 f0
281474976710700 -rwxr-xr-x 1 root root 0 Aug 14 22:52 f1
281474976710692 -rwxr-xr-x 1 root root 0 Jul 15 00:23 vol1_f0.txt

* After patch

$ mount.cifs //srv/test /mnt/1 -o ...,serverino
$ ls -li /mnt/1/vol0
total 1
590 drwxr-xr-x 2 root root 0 Jul 15 00:23 $RECYCLE.BIN
594 drwxr-xr-x 2 root root 0 Jul 18 18:23 System Volume Information
591 -rwxr-xr-x 1 root root 0 Aug 14 21:53 f0
592 -rwxr-xr-x 1 root root 0 Aug 15 18:52 f2
593 drwxr-xr-x 2 root root 0 Aug 12 19:39 foo
595 -rwxr-xr-x 1 root root 5 Aug  4 21:18 vol0_f0.txt
$ ls -li /mnt/1/vol1
total 0
596 drwxr-xr-x 2 root root 0 Jul 15 00:23 $RECYCLE.BIN
600 drwxr-xr-x 2 root root 0 Jul 18 18:23 System Volume Information
597 drwxr-xr-x 2 root root 0 Aug 12 19:39 bar
598 -rwxr-xr-x 1 root root 0 Aug 14 22:03 f0
599 -rwxr-xr-x 1 root root 0 Aug 14 22:52 f1
601 -rwxr-xr-x 1 root root 0 Jul 15 00:23 vol1_f0.txt

Signed-off-by: Paulo Alcantara (SUSE) <[email protected]>
Signed-off-by: Steve French <[email protected]>

Author: Paulo Alcantara

fs/smb/client/cifsglob.h

@@ -1094,7 +1094,7 @@ cap_unix(struct cifs_ses *ses)
  * inode with new info
  */
 
-#define CIFS_FATTR_DFS_REFERRAL		0x1
+#define CIFS_FATTR_JUNCTION		0x1
 #define CIFS_FATTR_DELETE_PENDING	0x2
 #define CIFS_FATTR_NEED_REVAL		0x4
 #define CIFS_FATTR_INO_COLLISION	0x8