cifs: don't use CIFSGetSrvInodeNumber in is_path_accessible

Because it's lighter weight, CIFS tries to use CIFSGetSrvInodeNumber to
verify the accessibility of the root inode and then falls back to doing a
full QPathInfo if that fails with -EOPNOTSUPP. I have at least a report
of a server that returns NT_STATUS_INTERNAL_ERROR rather than something
that translates to EOPNOTSUPP.

Rather than trying to be clever with that call, just have
is_path_accessible do a normal QPathInfo. That call is widely
supported and it shouldn't increase the overhead significantly.

Cc: Stable <stable@kernel.org>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

fs/cifs/connect.c

@@ -2220,16 +2220,8 @@ is_path_accessible(int xid, struct cifsTconInfo *tcon,
 		   struct cifs_sb_info *cifs_sb, const char *full_path)
 {
 	int rc;
-	__u64 inode_num;
 	FILE_ALL_INFO *pfile_info;
 
-	rc = CIFSGetSrvInodeNumber(xid, tcon, full_path, &inode_num,
-				   cifs_sb->local_nls,
-				   cifs_sb->mnt_cifs_flags &
-						CIFS_MOUNT_MAP_SPECIAL_CHR);
-	if (rc != -EOPNOTSUPP)
-		return rc;
-
 	pfile_info = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 	if (pfile_info == NULL)
 		return -ENOMEM;