CIFS: Make use of common cifs_build_path_to_root for CIFS and SMB2

because the is no difference here. This also adds support of prefixpath
mount option for SMB2.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>

fs/cifs/cifsfs.c

@@ -539,7 +539,7 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
 	char *s, *p;
 	char sep;
 
-	full_path = build_path_to_root(vol, cifs_sb,
+	full_path = cifs_build_path_to_root(vol, cifs_sb,
 					    cifs_sb_master_tcon(cifs_sb));
 	if (full_path == NULL)
 		return ERR_PTR(-ENOMEM);

fs/cifs/cifsglob.h

@@ -280,9 +280,6 @@ struct smb_version_operations {
 	/* set attributes */
 	int (*set_file_info)(struct inode *, const char *, FILE_BASIC_INFO *,
 			     const unsigned int);
-	/* build a full path to the root of the mount */
-	char * (*build_path_to_root)(struct smb_vol *, struct cifs_sb_info *,
-				     struct cifs_tcon *);
 	/* check if we can send an echo or nor */
 	bool (*can_echo)(struct TCP_Server_Info *);
 	/* send echo request */
@@ -1084,15 +1081,6 @@ convert_delimiter(char *path, char delim)
 	}
 }
 
-static inline char *
-build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
-		   struct cifs_tcon *tcon)
-{
-	if (!vol->ops->build_path_to_root)
-		return NULL;
-	return vol->ops->build_path_to_root(vol, cifs_sb, tcon);
-}
-
 #ifdef CONFIG_CIFS_STATS
 #define cifs_stats_inc atomic_inc
 

fs/cifs/cifsproto.h

@@ -60,6 +60,9 @@ extern int init_cifs_idmap(void);
 extern void exit_cifs_idmap(void);
 extern void cifs_destroy_idmaptrees(void);
 extern char *build_path_from_dentry(struct dentry *);
+extern char *cifs_build_path_to_root(struct smb_vol *vol,
+				     struct cifs_sb_info *cifs_sb,
+				     struct cifs_tcon *tcon);
 extern char *build_wildcard_path_from_dentry(struct dentry *direntry);
 extern char *cifs_compose_mount_options(const char *sb_mountdata,
 		const char *fullpath, const struct dfs_info3_param *ref,

fs/cifs/connect.c

@@ -3261,8 +3261,10 @@ cifs_cleanup_volume_info(struct smb_vol *volume_info)
 
 
 #ifdef CONFIG_CIFS_DFS_UPCALL
-/* build_path_to_root returns full path to root when
- * we do not have an exiting connection (tcon) */
+/*
+ * cifs_build_path_to_root returns full path to root when we do not have an
+ * exiting connection (tcon)
+ */
 static char *
 build_unc_path_to_root(const struct smb_vol *vol,
 		const struct cifs_sb_info *cifs_sb)
@@ -3518,8 +3520,10 @@ cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
 			rc = -ENOSYS;
 			goto mount_fail_check;
 		}
-		/* build_path_to_root works only when we have a valid tcon */
-		full_path = build_path_to_root(volume_info, cifs_sb, tcon);
+		/*
+		 * cifs_build_path_to_root works only when we have a valid tcon
+		 */
+		full_path = cifs_build_path_to_root(volume_info, cifs_sb, tcon);
 		if (full_path == NULL) {
 			rc = -ENOMEM;
 			goto mount_fail_check;

fs/cifs/dir.c

@@ -44,6 +44,37 @@ renew_parental_timestamps(struct dentry *direntry)
 	} while (!IS_ROOT(direntry));
 }
 
+char *
+cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
+			struct cifs_tcon *tcon)
+{
+	int pplen = vol->prepath ? strlen(vol->prepath) : 0;
+	int dfsplen;
+	char *full_path = NULL;
+
+	/* if no prefix path, simply set path to the root of share to "" */
+	if (pplen == 0) {
+		full_path = kzalloc(1, GFP_KERNEL);
+		return full_path;
+	}
+
+	if (tcon->Flags & SMB_SHARE_IS_IN_DFS)
+		dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
+	else
+		dfsplen = 0;
+
+	full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
+	if (full_path == NULL)
+		return full_path;
+
+	if (dfsplen)
+		strncpy(full_path, tcon->treeName, dfsplen);
+	strncpy(full_path + dfsplen, vol->prepath, pplen);
+	convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
+	full_path[dfsplen + pplen] = 0; /* add trailing null */
+	return full_path;
+}
+
 /* Note: caller must free return buffer */
 char *
 build_path_from_dentry(struct dentry *direntry)

fs/cifs/smb1ops.c

@@ -575,37 +575,6 @@ cifs_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 	return CIFSSMBQFileInfo(xid, tcon, fid->netfid, data);
 }
 
-static char *
-cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
-			struct cifs_tcon *tcon)
-{
-	int pplen = vol->prepath ? strlen(vol->prepath) : 0;
-	int dfsplen;
-	char *full_path = NULL;
-
-	/* if no prefix path, simply set path to the root of share to "" */
-	if (pplen == 0) {
-		full_path = kzalloc(1, GFP_KERNEL);
-		return full_path;
-	}
-
-	if (tcon->Flags & SMB_SHARE_IS_IN_DFS)
-		dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
-	else
-		dfsplen = 0;
-
-	full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
-	if (full_path == NULL)
-		return full_path;
-
-	if (dfsplen)
-		strncpy(full_path, tcon->treeName, dfsplen);
-	strncpy(full_path + dfsplen, vol->prepath, pplen);
-	convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
-	full_path[dfsplen + pplen] = 0; /* add trailing null */
-	return full_path;
-}
-
 static void
 cifs_clear_stats(struct cifs_tcon *tcon)
 {
@@ -943,7 +912,6 @@ struct smb_version_operations smb1_operations = {
 	.set_path_size = CIFSSMBSetEOF,
 	.set_file_size = CIFSSMBSetFileSize,
 	.set_file_info = smb_set_file_info,
-	.build_path_to_root = cifs_build_path_to_root,
 	.echo = CIFSSMBEcho,
 	.mkdir = CIFSSMBMkDir,
 	.mkdir_setinfo = cifs_mkdir_setinfo,

fs/cifs/smb2ops.c

@@ -262,23 +262,6 @@ smb2_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 	return rc;
 }
 
-static char *
-smb2_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
-			struct cifs_tcon *tcon)
-{
-	int pplen = vol->prepath ? strlen(vol->prepath) : 0;
-	char *full_path = NULL;
-
-	/* if no prefix path, simply set path to the root of share to "" */
-	if (pplen == 0) {
-		full_path = kzalloc(2, GFP_KERNEL);
-		return full_path;
-	}
-
-	cERROR(1, "prefixpath is not supported for SMB2 now");
-	return NULL;
-}
-
 static bool
 smb2_can_echo(struct TCP_Server_Info *server)
 {
@@ -613,7 +596,6 @@ struct smb_version_operations smb21_operations = {
 	.set_path_size = smb2_set_path_size,
 	.set_file_size = smb2_set_file_size,
 	.set_file_info = smb2_set_file_info,
-	.build_path_to_root = smb2_build_path_to_root,
 	.mkdir = smb2_mkdir,
 	.mkdir_setinfo = smb2_mkdir_setinfo,
 	.rmdir = smb2_rmdir,