cifs: fix noserverino handling when unix extensions are enabled

The uniqueid field sent by the server when unix extensions are enabled
is currently used sometimes when it shouldn't be. The readdir codepath
is correct, but most others are not. Fix it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/cifsproto.h

@@ -110,6 +110,7 @@ extern int cifs_posix_open(char *full_path, struct inode **pinode,
 				struct super_block *sb,
 				int mode, int oflags,
 				__u32 *poplock, __u16 *pnetfid, int xid);
+void cifs_fill_uniqueid(struct super_block *sb, struct cifs_fattr *fattr);
 extern void cifs_unix_basic_to_fattr(struct cifs_fattr *fattr,
 				     FILE_UNIX_BASIC_INFO *info,
 				     struct cifs_sb_info *cifs_sb);

fs/cifs/dir.c

@@ -248,6 +248,7 @@ int cifs_posix_open(char *full_path, struct inode **pinode,
 
 	/* get new inode and set it up */
 	if (*pinode == NULL) {
+		cifs_fill_uniqueid(sb, &fattr);
 		*pinode = cifs_iget(sb, &fattr);
 		if (!*pinode) {
 			rc = -ENOMEM;

fs/cifs/inode.c

@@ -169,6 +169,17 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
 	cifs_set_ops(inode, fattr->cf_flags & CIFS_FATTR_DFS_REFERRAL);
 }
 
+void
+cifs_fill_uniqueid(struct super_block *sb, struct cifs_fattr *fattr)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)
+		return;
+
+	fattr->cf_uniqueid = iunique(sb, ROOT_I);
+}
+
 /* Fill a cifs_fattr struct with info from FILE_UNIX_BASIC_INFO. */
 void
 cifs_unix_basic_to_fattr(struct cifs_fattr *fattr, FILE_UNIX_BASIC_INFO *info,
@@ -322,6 +333,7 @@ int cifs_get_inode_info_unix(struct inode **pinode,
 
 	if (*pinode == NULL) {
 		/* get new inode */
+		cifs_fill_uniqueid(sb, &fattr);
 		*pinode = cifs_iget(sb, &fattr);
 		if (!*pinode)
 			rc = -ENOMEM;
@@ -1197,6 +1209,7 @@ int cifs_mkdir(struct inode *inode, struct dentry *direntry, int mode)
 				direntry->d_op = &cifs_dentry_ops;
 
 			cifs_unix_basic_to_fattr(&fattr, pInfo, cifs_sb);
+			cifs_fill_uniqueid(inode->i_sb, &fattr);
 			newinode = cifs_iget(inode->i_sb, &fattr);
 			if (!newinode) {
 				kfree(pInfo);