[CIFS] DFS no longer experimental

Also updates some DFS flag definitions
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/Kconfig

@@ -118,6 +118,18 @@ config CIFS_DEBUG2
 	   option can be turned off unless you are debugging
 	   cifs problems.  If unsure, say N.
 
+config CIFS_DFS_UPCALL
+	  bool "DFS feature support"
+	  depends on CIFS && KEYS
+	  help
+	    Distributed File System (DFS) support is used to access shares
+	    transparently in an enterprise name space, even if the share
+	    moves to a different server.  This feature also enables
+	    an upcall mechanism for CIFS which contacts userspace helper
+	    utilities to provide server name resolution (host names to
+	    IP addresses) which is needed for implicit mounts of DFS junction
+	    points. If unsure, say N.
+
 config CIFS_EXPERIMENTAL
 	  bool "CIFS Experimental Features (EXPERIMENTAL)"
 	  depends on CIFS && EXPERIMENTAL
@@ -131,12 +143,3 @@ config CIFS_EXPERIMENTAL
 	    (which is disabled by default). See the file fs/cifs/README
 	    for more details.  If unsure, say N.
 
-config CIFS_DFS_UPCALL
-	  bool "DFS feature support (EXPERIMENTAL)"
-	  depends on CIFS_EXPERIMENTAL
-	  depends on KEYS
-	  help
-	    Enables an upcall mechanism for CIFS which contacts userspace
-	    helper utilities to provide server name resolution (host names to
-	    IP addresses) which is needed for implicit mounts of DFS junction
-	    points. If unsure, say N.

fs/cifs/cifspdu.h

@@ -1931,19 +1931,19 @@ typedef struct smb_com_transaction2_get_dfs_refer_req {
 #define DFS_TYPE_ROOT 0x0001
 
 /* Referral Entry Flags */
-#define DFS_NAME_LIST_REF 0x0200
+#define DFS_NAME_LIST_REF 0x0200 /* set for domain or DC referral responses */
+#define DFS_TARGET_SET_BOUNDARY 0x0400 /* only valid with version 4 dfs req */
 
-typedef struct dfs_referral_level_3 {
-	__le16 VersionNumber;
+typedef struct dfs_referral_level_3 { /* version 4 is same, + one flag bit */
+	__le16 VersionNumber;  /* must be 3 or 4 */
 	__le16 Size;
 	__le16 ServerType; /* 0x0001 = root targets; 0x0000 = link targets */
-	__le16 ReferralEntryFlags; /* 0x0200 bit set only for domain
-				      or DC referral responce */
+	__le16 ReferralEntryFlags;
 	__le32 TimeToLive;
 	__le16 DfsPathOffset;
 	__le16 DfsAlternatePathOffset;
 	__le16 NetworkAddressOffset; /* offset of the link target */
-	__le16 ServiceSiteGuid;
+	__u8   ServiceSiteGuid[16];  /* MBZ, ignored */
 } __attribute__((packed)) REFERRAL3;
 
 typedef struct smb_com_transaction_get_dfs_refer_rsp {
@@ -1953,15 +1953,15 @@ typedef struct smb_com_transaction_get_dfs_refer_rsp {
 	__u8 Pad;
 	__le16 PathConsumed;
 	__le16 NumberOfReferrals;
-	__le16 DFSFlags;
-	__u16 Pad2;
+	__le32 DFSFlags;
 	REFERRAL3 referrals[1];	/* array of level 3 dfs_referral structures */
 	/* followed by the strings pointed to by the referral structures */
 } __attribute__((packed)) TRANSACTION2_GET_DFS_REFER_RSP;
 
 /* DFS Flags */
-#define DFSREF_REFERRAL_SERVER  0x0001
-#define DFSREF_STORAGE_SERVER   0x0002
+#define DFSREF_REFERRAL_SERVER  0x00000001 /* all targets are DFS roots */
+#define DFSREF_STORAGE_SERVER   0x00000002 /* no further ref requests needed */
+#define DFSREF_TARGET_FAILBACK  0x00000004 /* only for DFS referral version 4 */
 
 /* IOCTL information */
 /*