[CIFS] on reconnect to Samba - reset the unix capabilities

After temporary server or network failure and reconneciton, we were not
resending the unix capabilities via SetFSInfo - which confused Samba posix
byte range locking code.

Discovered by jra
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/Kconfig

@@ -1871,20 +1871,14 @@ config CIFS
 	  file servers such as Windows 2000 (including Windows 2003, NT 4  
 	  and Windows XP) as well by Samba (which provides excellent CIFS
 	  server support for Linux and many other operating systems). Limited
-	  support for Windows ME and similar servers is provided as well. 
-	  You must use the smbfs client filesystem to access older SMB servers
-	  such as OS/2 and DOS.
+	  support for OS/2 and Windows ME and similar servers is provided as well.
 
 	  The intent of the cifs module is to provide an advanced
-	  network file system client for mounting to CIFS compliant servers, 
+	  network file system client for mounting to CIFS compliant servers,
 	  including support for dfs (hierarchical name space), secure per-user
 	  session establishment, safe distributed caching (oplock), optional
-	  packet signing, Unicode and other internationalization improvements, 
-	  and optional Winbind (nsswitch) integration. You do not need to enable
-	  cifs if running only a (Samba) server. It is possible to enable both
-	  smbfs and cifs (e.g. if you are using CIFS for accessing Windows 2003
-	  and Samba 3 servers, and smbfs for accessing old servers). If you need 
-	  to mount to Samba or Windows from this machine, say Y.
+	  packet signing, Unicode and other internationalization improvements. 
+	  If you need to mount to Samba or Windows from this machine, say Y.
 
 config CIFS_STATS
         bool "CIFS statistics"
@@ -1977,14 +1971,13 @@ config CIFS_EXPERIMENTAL
 	  depends on CIFS && EXPERIMENTAL
 	  help
 	    Enables cifs features under testing. These features are
-	    experimental and currently include support for writepages
-	    (multipage writebehind performance improvements) and directory
-	    change notification ie fcntl(F_DNOTIFY) as well as some security
-	    improvements.  Some also depend on setting at runtime the
-	    pseudo-file /proc/fs/cifs/Experimental (which is disabled by
-	    default). See the file fs/cifs/README for more details.
-
-	    If unsure, say N.
+	    experimental and currently include DFS support and directory 
+	    change notification ie fcntl(F_DNOTIFY), as well as the upcall
+	    mechanism which will be used for Kerberos session negotiation
+	    and uid remapping.  Some of these features also may depend on 
+	    setting a value of 1 to the pseudo-file /proc/fs/cifs/Experimental
+	    (which is disabled by default). See the file fs/cifs/README 
+	    for more details.  If unsure, say N.
 
 config CIFS_UPCALL
 	  bool "Kerberos/SPNEGO advanced session setup (EXPERIMENTAL)"

fs/cifs/CHANGES

@@ -4,7 +4,12 @@ Fix oops in list_del during mount caused by unaligned string.
 Fix file corruption which could occur on some large file
 copies caused by writepages page i/o completion bug.
 Seek to SEEK_END forces check for update of file size for non-cached
-files.
+files. Allow file size to be updated on remote extend of locally open,
+non-cached file.  Fix reconnect to newer Samba servers (or other servers
+which support the CIFS Unix/POSIX extensions) so that we again tell the
+server the Unix/POSIX cifs capabilities which we support (SetFSInfo).
+Add experimental support for new POSIX Open/Mkdir (which returns
+stat information on the open, and allows setting the mode).
 
 Version 1.46
 ------------

fs/cifs/TODO

@@ -128,3 +128,11 @@ negotiated size) and send larger write sizes to modern servers.
 
 4) More exhaustively test against less common servers.  More testing
 against Windows 9x, Windows ME servers.
+
+DOS attrs - returned as pseudo-xattr in Samba format (check VFAT and NTFS for this too)
+
+mount check for unmatched uids - and uid override
+
+Add mount option for Linux extension disable per mount, and partial disable per mount (uid off, symlink/fifo/mknod on but what about posix acls?) 
+
+Free threads at umount --force that are stuck on the sesSem

fs/cifs/cifsfs.h

@@ -100,5 +100,5 @@ extern ssize_t	cifs_getxattr(struct dentry *, const char *, void *, size_t);
 extern ssize_t	cifs_listxattr(struct dentry *, char *, size_t);
 extern int cifs_ioctl (struct inode * inode, struct file * filep,
 		       unsigned int command, unsigned long arg);
-#define CIFS_VERSION   "1.47"
+#define CIFS_VERSION   "1.48"
 #endif				/* _CIFSFS_H */

fs/cifs/cifspdu.h

@@ -2108,7 +2108,7 @@ typedef struct {
 
 typedef struct {
 	/* reply varies based on requested level */
-} __atribute__((packed)) OPEN_PSX_RSP; /* level 0x209 SetPathInfo data */
+} __attribute__((packed)) OPEN_PSX_RSP; /* level 0x209 SetPathInfo data */
 
 
 struct file_internal_info {

fs/cifs/cifsproto.h

@@ -23,6 +23,7 @@
 #include <linux/nls.h>
 
 struct statfs;
+struct smb_vol;
 
 /*
  *****************************************************************
@@ -147,6 +148,8 @@ extern int get_dfs_path(int xid, struct cifsSesInfo *pSesInfo,
 			unsigned int *pnum_referrals, 
 			unsigned char ** preferrals,
 			int remap);
+extern void reset_cifs_unix_caps(int xid, struct cifsTconInfo *tcon,
+				 struct super_block * sb, struct smb_vol * vol);
 extern int CIFSSMBQFSInfo(const int xid, struct cifsTconInfo *tcon,
 			struct kstatfs *FSData);
 extern int SMBOldQFSInfo(const int xid, struct cifsTconInfo *tcon,

fs/cifs/cifssmb.c

@@ -158,9 +158,15 @@ small_smb_init(int smb_command, int wct, struct cifsTconInfo *tcon,
 							nls_codepage);
 			if(!rc && (tcon->tidStatus == CifsNeedReconnect)) {
 				mark_open_files_invalid(tcon);
-				rc = CIFSTCon(0, tcon->ses, tcon->treeName, tcon
-					, nls_codepage);
+				rc = CIFSTCon(0, tcon->ses, tcon->treeName, 
+					      tcon, nls_codepage);
 				up(&tcon->ses->sesSem);
+				/* tell server which Unix caps we support */
+				if (tcon->ses->capabilities & CAP_UNIX)
+					reset_cifs_unix_caps(0 /* no xid */,
+						tcon, 
+						NULL /* we do not know sb */,
+						NULL /* no vol info */);	
 				/* BB FIXME add code to check if wsize needs
 				   update due to negotiated smb buffer size
 				   shrinking */
@@ -298,6 +304,12 @@ smb_init(int smb_command, int wct, struct cifsTconInfo *tcon,
 				rc = CIFSTCon(0, tcon->ses, tcon->treeName,
 					      tcon, nls_codepage);
 				up(&tcon->ses->sesSem);
+				/* tell server which Unix caps we support */
+				if (tcon->ses->capabilities & CAP_UNIX)
+					reset_cifs_unix_caps(0 /* no xid */,
+						tcon, 
+						NULL /* do not know sb */,
+						NULL /* no vol info */);
 				/* BB FIXME add code to check if wsize needs
 				update due to negotiated smb buffer size
 				shrinking */

fs/cifs/connect.c

@@ -1613,6 +1613,76 @@ ipv6_connect(struct sockaddr_in6 *psin_server, struct socket **csocket)
 	return rc;
 }
 
+void reset_cifs_unix_caps(int xid, struct cifsTconInfo * tcon, 
+			  struct super_block * sb, struct smb_vol * vol_info)
+{
+	/* if we are reconnecting then should we check to see if
+	 * any requested capabilities changed locally e.g. via
+	 * remount but we can not do much about it here
+	 * if they have (even if we could detect it by the following)
+	 * Perhaps we could add a backpointer to array of sb from tcon
+	 * or if we change to make all sb to same share the same
+	 * sb as NFS - then we only have one backpointer to sb.
+	 * What if we wanted to mount the server share twice once with
+	 * and once without posixacls or posix paths? */
+	__u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
+	   
+	 
+	if(!CIFSSMBQFSUnixInfo(xid, tcon)) {
+		__u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
+		
+		/* check for reconnect case in which we do not
+		   want to change the mount behavior if we can avoid it */
+		if(vol_info == NULL) {
+			/* turn off POSIX ACL and PATHNAMES if not set 
+			   originally at mount time */
+			if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
+				cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
+			if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0)
+				cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
+				
+
+			 
+			
+		}
+		
+		cap &= CIFS_UNIX_CAP_MASK;
+		if(vol_info && vol_info->no_psx_acl)
+			cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
+		else if(CIFS_UNIX_POSIX_ACL_CAP & cap) {
+			cFYI(1,("negotiated posix acl support"));
+			if(sb)
+				sb->s_flags |= MS_POSIXACL;
+		}
+
+		if(vol_info && vol_info->posix_paths == 0)
+			cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
+		else if(cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
+			cFYI(1,("negotiate posix pathnames"));
+			if(sb)
+				CIFS_SB(sb)->mnt_cifs_flags |= 
+					CIFS_MOUNT_POSIX_PATHS;
+		}
+			
+		cFYI(1,("Negotiate caps 0x%x",(int)cap));
+#ifdef CONFIG_CIFS_DEBUG2
+		if(cap & CIFS_UNIX_FCNTL_CAP)
+			cFYI(1,("FCNTL cap"));
+		if(cap & CIFS_UNIX_EXTATTR_CAP)
+			cFYI(1,("EXTATTR cap"));
+		if(cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
+			cFYI(1,("POSIX path cap"));
+		if(cap & CIFS_UNIX_XATTR_CAP)
+			cFYI(1,("XATTR cap"));
+		if(cap & CIFS_UNIX_POSIX_ACL_CAP)
+			cFYI(1,("POSIX ACL cap"));
+#endif /* CIFS_DEBUG2 */
+		if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
+			cFYI(1,("setting capabilities failed"));
+		}
+	}
+}
+
 int
 cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 	   char *mount_data, const char *devname)
@@ -1928,20 +1998,25 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 			if (tcon == NULL)
 				rc = -ENOMEM;
 			else {
-				/* check for null share name ie connect to dfs root */
+				/* check for null share name ie connecting to 
+				 * dfs root */
 
-				/* BB check if this works for exactly length three strings */
+				/* BB check if this works for exactly length 
+				 * three strings */
 				if ((strchr(volume_info.UNC + 3, '\\') == NULL)
 				    && (strchr(volume_info.UNC + 3, '/') ==
 					NULL)) {
 					rc = connect_to_dfs_path(xid, pSesInfo,
-							"", cifs_sb->local_nls,
-							cifs_sb->mnt_cifs_flags & 
-							  CIFS_MOUNT_MAP_SPECIAL_CHR);
+						"", cifs_sb->local_nls,
+						cifs_sb->mnt_cifs_flags & 
+						  CIFS_MOUNT_MAP_SPECIAL_CHR);
 					kfree(volume_info.UNC);
 					FreeXid(xid);
 					return -ENODEV;
 				} else {
+					/* BB Do we need to wrap sesSem around
+					 * this TCon call and Unix SetFS as
+					 * we do on SessSetup and reconnect? */
 					rc = CIFSTCon(xid, pSesInfo, 
 						volume_info.UNC,
 						tcon, cifs_sb->local_nls);
@@ -1962,6 +2037,7 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 			sb->s_maxbytes = (u64) 1 << 31;	/* 2 GB */
 	}
 
+	/* BB FIXME fix time_gran to be larger for LANMAN sessions */
 	sb->s_time_gran = 100;
 
 /* on error free sesinfo and tcon struct if needed */
@@ -2006,45 +2082,11 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 		/* 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)) {
-				__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;
-				}
-
-				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));
-#ifdef CONFIG_CIFS_DEBUG2
-				if(cap & CIFS_UNIX_FCNTL_CAP)
-					cFYI(1,("FCNTL cap"));
-				if(cap & CIFS_UNIX_EXTATTR_CAP)
-					cFYI(1,("EXTATTR cap"));
-				if(cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
-					cFYI(1,("POSIX path cap"));
-				if(cap & CIFS_UNIX_XATTR_CAP)
-					cFYI(1,("XATTR cap"));
-				if(cap & CIFS_UNIX_POSIX_ACL_CAP)
-					cFYI(1,("POSIX ACL cap"));
-#endif /* CIFS_DEBUG2 */
-				if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
-					cFYI(1,("setting capabilities failed"));
-				}
-			}
-		}
+		
+		/* tell server which Unix caps we support */
+		if (tcon->ses->capabilities & CAP_UNIX)
+			reset_cifs_unix_caps(xid, tcon, sb, &volume_info);
+		
 		if (!(tcon->ses->capabilities & CAP_LARGE_WRITE_X))
 			cifs_sb->wsize = min(cifs_sb->wsize,
 					     (tcon->ses->server->maxBuf -