1 files changed, 32 insertions, 0 deletions

diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index fa210010358d..7195fadf1cfa 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -489,6 +489,37 @@ cifs_get_srv_inum(const unsigned int xid, struct cifs_tcon *tcon,
                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 }
 
+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;
+}
+
 struct smb_version_operations smb1_operations = {
         .send_cancel = send_nt_cancel,
         .compare_fids = cifs_compare_fids,
@@ -518,6 +549,7 @@ struct smb_version_operations smb1_operations = {
         .is_path_accessible = cifs_is_path_accessible,
         .query_path_info = cifs_query_path_info,
         .get_srv_inum = cifs_get_srv_inum,
+        .build_path_to_root = cifs_build_path_to_root,
 };
 
 struct smb_version_values smb1_values = {