[CIFS] Make POSIX CIFS Extensions SetFSInfo match exactly what we want

not just the posix path feature.
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/README

@@ -422,6 +422,13 @@ A partial list of the supported mount options follows:
  nomapchars     Do not translate any of these seven characters (default).
  nocase         Request case insensitive path name matching (case
 		sensitive is the default if the server suports it).
+ posixpaths     If CIFS Unix extensions are supported, attempt to
+		negotiate posix path name support which allows certain
+		characters forbidden in typical CIFS filenames, without
+		requiring remapping. (default)
+ noposixpaths   If CIFS Unix extensions are supported, do not request
+		posix path name support (this may cause servers to
+		reject creatingfile with certain reserved characters).
  nobrl          Do not send byte range lock requests to the server.
 		This is necessary for certain applications that break
 		with cifs style mandatory byte range locks (and most

fs/cifs/cifspdu.h

@@ -1789,7 +1789,13 @@ typedef struct {
 #define CIFS_UNIX_POSIX_ACL_CAP         0x00000002 /* support getfacl/setfacl */
 #define CIFS_UNIX_XATTR_CAP             0x00000004 /* support new namespace   */
 #define CIFS_UNIX_EXTATTR_CAP           0x00000008 /* support chattr/chflag   */
-#define CIFS_UNIX_POSIX_PATHNAMES_CAP   0x00000010 /* Use POSIX pathnames on the wire. */
+#define CIFS_UNIX_POSIX_PATHNAMES_CAP   0x00000010 /* Allow POSIX path chars  */
+#ifdef CONFIG_CIFS_POSIX
+#define CIFS_UNIX_CAP_MASK              0x0000001b
+#else 
+#define CIFS_UNIX_CAP_MASK              0x00000013
+#endif /* CONFIG_CIFS_POSIX */
+
 
 #define CIFS_POSIX_EXTENSIONS           0x00000010 /* support for new QFSInfo */
 

fs/cifs/connect.c

@@ -1920,27 +1920,34 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 		cifs_sb->tcon = tcon;
 		tcon->ses = pSesInfo;
 
-		/* do not care if following two calls succeed - informational only */
+		/* do not care if following two calls succeed - informational */
 		CIFSSMBQFSDeviceInfo(xid, tcon);
 		CIFSSMBQFSAttributeInfo(xid, tcon);
+
 		if (tcon->ses->capabilities & CAP_UNIX) {
 			if(!CIFSSMBQFSUnixInfo(xid, tcon)) {
-				if(!volume_info.no_psx_acl) {
-					if(CIFS_UNIX_POSIX_ACL_CAP & 
-					   le64_to_cpu(tcon->fsUnixInfo.Capability))
-						cFYI(1,("server negotiated posix acl support"));
+				__u64 cap = 
+				       le64_to_cpu(tcon->fsUnixInfo.Capability);
+				cap &= CIFS_UNIX_CAP_MASK;
+				if(volume_info.no_psx_acl)
+					cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
+				else if(CIFS_UNIX_POSIX_ACL_CAP & cap) {
+					cFYI(1,("negotiated posix acl support"));
 					sb->s_flags |= MS_POSIXACL;
 				}
 
-				/* Try and negotiate POSIX pathnames if we can. */
-				if (volume_info.posix_paths && (CIFS_UNIX_POSIX_PATHNAMES_CAP &
-				    le64_to_cpu(tcon->fsUnixInfo.Capability))) {
-					if (!CIFSSMBSetFSUnixInfo(xid, tcon, CIFS_UNIX_POSIX_PATHNAMES_CAP))  {
-						cFYI(1,("negotiated posix pathnames support"));
-						cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
-					} else {
-						cFYI(1,("posix pathnames support requested but not supported"));
+				if(volume_info.posix_paths == 0)
+					cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
+				else if(cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
+					cFYI(1,("negotiate posix pathnames"));
+					cifs_sb->mnt_cifs_flags |= 
+						CIFS_MOUNT_POSIX_PATHS;
 				}
+					
+				cFYI(1,("Negotiate caps 0x%x",(int)cap));
+
+				if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
+					cFYI(1,("setting capabilities failed"));
 				}
 			}
 		}

fs/cifs/file.c

@@ -649,7 +649,9 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
 	wire */
 	if (IS_GETLK(cmd)) {
 		if(experimEnabled && 
-		   (cifs_sb->tcon->ses->capabilities & CAP_UNIX)) {
+		   (cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
+		   (CIFS_UNIX_FCNTL_CAP & 
+			le64_to_cpu(cifs_sb->tcon->fsUnixInfo.Capability))) {
 			int posix_lock_type;
 			if(lockType & LOCKING_ANDX_SHARED_LOCK)
 				posix_lock_type = CIFS_RDLCK;
@@ -686,7 +688,9 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *pfLock)
 		return rc;
 	}
 	if (experimEnabled &&
-		(cifs_sb->tcon->ses->capabilities & CAP_UNIX)) {
+		(cifs_sb->tcon->ses->capabilities & CAP_UNIX) &&
+		(CIFS_UNIX_FCNTL_CAP &
+			 le64_to_cpu(cifs_sb->tcon->fsUnixInfo.Capability))) {
 		int posix_lock_type;
 		if(lockType & LOCKING_ANDX_SHARED_LOCK)
 			posix_lock_type = CIFS_RDLCK;