Merge bk://cifs.bkbits.net/linux-2.5cifs

into penguin.transmeta.com:/home/torvalds/v2.5/linux

fs/cifs/AUTHORS

@@ -20,3 +20,9 @@ Patch Contributors
 Zwane Mwaikambo
 Andi Kleen
 
+Test case and Bug Report contributors
+-------------------------------------
+Thanks to those in the community who have submitted detailed bug reports
+and debug of problems they have found:  Jochen Dolze, David Blaine,
+Rene Scharfe, Martin Josefsson and others. 
+

fs/cifs/CHANGES

+Version 0.77
+------------
+Fix display of NTFS DFS junctions to display as symlinks.
+They are the network equivalent.  Fix oops in 
+cifs_partialpagewrite caused by missing spinlock protection
+of openfile linked list.  Allow writebehind caching errors to 
+be returned to the application at file close.
+
+Version 0.76
+------------
+Clean up options displayed in /proc/mounts by show_options to
+be more consistent with other filesystems.
+
 Version 0.75
 ------------
 Fix delete of readonly file to Windows servers.  Reflect

fs/cifs/TODO

@@ -18,6 +18,8 @@ c) multi-user mounts - multiplexed sessionsetups over single vc
 d) Kerberos/SPNEGO session setup support - (started)
 
 e) NTLMv2 authentication and MD5-HMAC signing SMB PDUs - (mostly implemented)
+	signing necessary for some Windows 2003 servers in domain 
+	controller mode.
 
 f) oplock support (ie safe CIFS distributed file caching) is not quite complete.
 In addition Directory entry caching relies on a 1 second timer, rather than 
@@ -52,7 +54,8 @@ file opens on top of each other by incrementing reference count rather
 than resending (helps reduce server resource utilization and avoid
 spurious oplock breaks).
 
-KNOWN BUGS (updated March 7, 2003)
+
+KNOWN BUGS (updated May 16, 2003)
 ====================================
 1) existing symbolic links (Windows reparse points) are recognized but
 can not be created remotely. They are implemented for Samba and those that
@@ -60,6 +63,11 @@ support the CIFS Unix extensions but Samba has a bug currently handling
 symlink text beginning with slash
 2) delete of file with read-only attribute set will fail (may be ok)
 3) mount helper syntax not quite matching man page
+4) follow_link and readdir code does not follow dfs junctions
+but recognizes them
+5) create of new files to FAT partitions on Windows servers can
+succeed but still return access denied (appears to be Windows 
+not client problem).  NTFS partitions do not have this problem.
 
 Misc testing to do
 =================
@@ -68,6 +76,6 @@ types.
 
 2) Run dbench
 
-3) Finish FSX testing on SMP now that we workaround the Samba bug
+3) Finish high stress fsx testing on SMP clients
 
 4) Additional performance testing and optimization

fs/cifs/cifsfs.c

@@ -209,8 +209,8 @@ cifs_destroy_inode(struct inode *inode)
 
 /*
  * cifs_show_options() is for displaying mount options in /proc/mounts.
- * It tries to avoid showing settings that were not changed from their
- * defaults.
+ * Not all settable options are displayed but most of the important
+ * ones are.
  */
 static int
 cifs_show_options(struct seq_file *s, struct vfsmount *m)
@@ -219,14 +219,18 @@ cifs_show_options(struct seq_file *s, struct vfsmount *m)
 
 	cifs_sb = CIFS_SB(m->mnt_sb);
 
-	if (cifs_sb)
+	if (cifs_sb) {
 		if (cifs_sb->tcon) {
-			seq_printf(s, ", TARGET: %s ", cifs_sb->tcon->treeName);
-			seq_printf(s, "FS TYPE: %s ",
-				   cifs_sb->tcon->nativeFileSystem);
+			seq_printf(s, ",unc=%s", cifs_sb->tcon->treeName);
 			if (cifs_sb->tcon->ses->userName)
-				seq_printf(s, " USER: %s ",
+				seq_printf(s, ",username=%s",
 					   cifs_sb->tcon->ses->userName);
+			if(cifs_sb->tcon->ses->domainName)
+				seq_printf(s, ",domain=%s",
+					cifs_sb->tcon->ses->domainName);
+		}
+		seq_printf(s, ",rsize=%d",cifs_sb->rsize);
+		seq_printf(s, ",wsize=%d",cifs_sb->wsize);
 	}
 	return 0;
 }
@@ -423,6 +427,7 @@ cifs_destroy_mids(void)
 static int cifs_oplock_thread(void * dummyarg)
 {
 	struct list_head * tmp;
+	struct list_head * tmp1;
 	struct oplock_q_entry * oplock_item;
 	struct file * pfile;
 	struct cifsTconInfo *pTcon;
@@ -438,9 +443,8 @@ static int cifs_oplock_thread(void * dummyarg)
 		/* BB add missing code */
 		cFYI(1,("oplock thread woken up - flush inode")); /* BB remove */
 		write_lock(&GlobalMid_Lock); 
-		list_for_each(tmp, &GlobalOplock_Q) {
-			oplock_item = list_entry(tmp, struct
-							       oplock_q_entry,
+		list_for_each_safe(tmp, tmp1, &GlobalOplock_Q) {
+			oplock_item = list_entry(tmp, struct oplock_q_entry,
 							       qhead);
 			if(oplock_item) {
 				pTcon = oplock_item->tcon;
@@ -449,6 +453,9 @@ static int cifs_oplock_thread(void * dummyarg)
 				DeleteOplockQEntry(oplock_item);
 				write_unlock(&GlobalMid_Lock);
 				rc = filemap_fdatawrite(pfile->f_dentry->d_inode->i_mapping);
+				if(rc)
+					CIFS_I(pfile->f_dentry->d_inode)->write_behind_rc 
+						= rc;
 				cFYI(1,("Oplock flush file %p rc %d",pfile,rc));
 				/* send oplock break */
 				write_lock(&GlobalMid_Lock);

fs/cifs/cifsglob.h

@@ -221,6 +221,7 @@ struct cifsInodeInfo {
 	struct list_head lockList;
 	/* BB add in lists for dirty pages - i.e. write caching info for oplock */
 	struct list_head openFileList;
+	int write_behind_rc;
 	__u32 cifsAttrs; /* e.g. DOS archive bit, sparse, compressed, system */
 	atomic_t inUse;	 /* num concurrent users (local openers cifs) of file*/
 	unsigned long time;	/* jiffies of last update/check of inode */

fs/cifs/cifspdu.h

@@ -1263,6 +1263,7 @@ typedef struct dfs_referral_level_3 {
 	__u16 ServerType;	/* 0x0001 = CIFS server */
 	__u16 ReferralFlags;	/* or proximity - not clear which since always set to zero - SNIA spec says 0x01 means strip off PathConsumed chars before submitting RequestFileName to remote node */
 	__u16 TimeToLive;
+	__u16 Proximity;
 	__u16 DfsPathOffset;
 	__u16 DfsAlternatePathOffset;
 	__u16 NetworkAddressOffset;

fs/cifs/cifsproto.h

@@ -127,13 +127,15 @@ extern int CIFSSMBUnixQPathInfo(const int xid,
 extern int CIFSGetDFSRefer(const int xid, struct cifsSesInfo *ses,
 			const unsigned char *searchName,
 			unsigned char **targetUNCs,
-			int *number_of_UNC_in_array,
+			unsigned int *number_of_UNC_in_array,
 			const struct nls_table *nls_codepage);
 
 extern int connect_to_dfs_path(int xid, struct cifsSesInfo *pSesInfo,
 			const char *old_path,
 			const struct nls_table *nls_codepage);
-
+extern int get_dfs_path(int xid, struct cifsSesInfo *pSesInfo,
+			const char *old_path, const struct nls_table *nls_codepage, 
+			unsigned int *pnum_referrals, unsigned char ** preferrals);
 extern int CIFSSMBQFSInfo(const int xid, struct cifsTconInfo *tcon,
 			struct statfs *FSData,
 			const struct nls_table *nls_codepage);

fs/cifs/cifssmb.c

@@ -1625,15 +1625,18 @@ int
 CIFSGetDFSRefer(const int xid, struct cifsSesInfo *ses,
 		const unsigned char *searchName,
 		unsigned char **targetUNCs,
-		int *number_of_UNC_in_array,
+		unsigned int *number_of_UNC_in_array,
 		const struct nls_table *nls_codepage)
 {
 /* TRANS2_GET_DFS_REFERRAL */
 	TRANSACTION2_GET_DFS_REFER_REQ *pSMB = NULL;
 	TRANSACTION2_GET_DFS_REFER_RSP *pSMBr = NULL;
+	struct dfs_referral_level_3 * referrals = NULL;
 	int rc = 0;
 	int bytes_returned;
 	int name_len;
+	unsigned int i;
+	char * temp;
 	*number_of_UNC_in_array = 0;
 	*targetUNCs = NULL;
 
@@ -1701,6 +1704,76 @@ CIFSGetDFSRefer(const int xid, struct cifsSesInfo *ses,
 		cFYI(1, ("Send error in GetDFSRefer = %d", rc));
 	} else {		/* decode response */
 /* BB Add logic to parse referrals here */
+		pSMBr->DataOffset = le16_to_cpu(pSMBr->DataOffset);
+		pSMBr->DataCount = le16_to_cpu(pSMBr->DataCount);
+		cFYI(1,
+		     ("Decoding GetDFSRefer response.  BCC: %d  Offset %d",
+		      pSMBr->ByteCount, pSMBr->DataOffset));
+		if ((pSMBr->ByteCount < 17) || (pSMBr->DataOffset > 512))	/* BB also check enough total bytes returned */
+			rc = -EIO;	/* bad smb */
+		else {
+			referrals = 
+			    (struct dfs_referral_level_3 *) 
+					(8 /* sizeof start of data block */ +
+					pSMBr->DataOffset +
+					(char *) &pSMBr->hdr.Protocol); 
+			cFYI(1,("num_referrals: %d dfs flags: 0x%x ... \nfor referral one refer size: 0x%x srv type: 0x%x refer flags: 0x%x ttl: 0x%x",pSMBr->NumberOfReferrals,pSMBr->DFSFlags, referrals->ReferralSize,referrals->ServerType,referrals->ReferralFlags,referrals->TimeToLive));
+			/* BB This field is actually two bytes in from start of
+			   data block so we could do safety check that DataBlock
+			   begins at address of pSMBr->NumberOfReferrals */
+			*number_of_UNC_in_array = le16_to_cpu(pSMBr->NumberOfReferrals);
+
+			/* BB Fix below so can return more than one referral */
+			if(*number_of_UNC_in_array > 1)
+				*number_of_UNC_in_array = 1;
+
+			/* get the length of the strings describing refs */
+			name_len = 0;
+			for(i=0;i<*number_of_UNC_in_array;i++) {
+				/* make sure that DfsPathOffset not past end */
+				referrals->DfsPathOffset = le16_to_cpu(referrals->DfsPathOffset);
+				if(referrals->DfsPathOffset > pSMBr->DataCount) {
+					/* if invalid referral, stop here and do 
+					not try to copy any more */
+					*number_of_UNC_in_array = i;
+					break;
+				} 
+				temp = ((char *)referrals) + referrals->DfsPathOffset;
+
+				if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE) {
+					name_len += UniStrnlen((wchar_t *)temp,pSMBr->DataCount);
+				} else {
+					name_len += strnlen(temp,pSMBr->DataCount);
+				}
+				referrals++;
+				/* BB add check that referral pointer does not fall off end PDU */
+				
+			}
+			/* BB add check for name_len bigger than bcc */
+			*targetUNCs = 
+				kmalloc(name_len+1+ (*number_of_UNC_in_array),GFP_KERNEL);
+			/* copy the ref strings */
+			referrals =  
+			    (struct dfs_referral_level_3 *) 
+					(8 /* sizeof data hdr */ +
+					pSMBr->DataOffset + 
+					(char *) &pSMBr->hdr.Protocol);
+
+			for(i=0;i<*number_of_UNC_in_array;i++) {
+				temp = ((char *)referrals) + referrals->DfsPathOffset;
+				if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE) {
+					cifs_strfromUCS_le(*targetUNCs,
+						(wchar_t *) temp, name_len, nls_codepage);
+				} else {
+					strncpy(*targetUNCs,temp,name_len);
+				}
+				/*  BB update target_uncs pointers */
+				referrals++;
+			}
+			temp = *targetUNCs;
+			temp[name_len] = 0;
+		}
+
 	}
 	if (pSMB)
 		buf_release(pSMB);

fs/cifs/connect.c

@@ -571,11 +571,32 @@ find_unc(__u32 new_target_ip_addr, char *uncName, char *userName)
 int
 connect_to_dfs_path(int xid, struct cifsSesInfo *pSesInfo,
 		    const char *old_path, const struct nls_table *nls_codepage)
+{
+	unsigned char *referrals = NULL;
+	unsigned int num_referrals;
+	int rc = 0;
+
+	rc = get_dfs_path(xid, pSesInfo,old_path, nls_codepage, 
+			&num_referrals, &referrals);
+
+	/* BB Add in code to: if valid refrl, if not ip address contact
+		the helper that resolves tcp names, mount to it, try to 
+		tcon to it unmount it if fail */
+
+	/* BB free memory for referrals string BB */
+
+	return rc;
+}
+
+int
+get_dfs_path(int xid, struct cifsSesInfo *pSesInfo,
+			const char *old_path, const struct nls_table *nls_codepage, 
+			unsigned int *pnum_referrals, unsigned char ** preferrals)
 {
 	char *temp_unc;
 	int rc = 0;
-	int num_referrals = 0;
-	unsigned char *referrals = NULL;
+
+	*pnum_referrals = 0;
 
 	if (pSesInfo->ipc_tid == 0) {
 		temp_unc = kmalloc(2 /* for slashes */ +
@@ -594,11 +615,10 @@ connect_to_dfs_path(int xid, struct cifsSesInfo *pSesInfo,
 		kfree(temp_unc);
 	}
 	if (rc == 0)
-		rc = CIFSGetDFSRefer(xid, pSesInfo, old_path, &referrals,
-				     &num_referrals, nls_codepage);
-
-	return -ENODEV;	/* BB remove and add return code processing */
+		rc = CIFSGetDFSRefer(xid, pSesInfo, old_path, preferrals,
+				     pnum_referrals, nls_codepage);
 
+	return rc;
 }
 
 int setup_session(unsigned int xid, struct cifsSesInfo *pSesInfo, struct nls_table * nls_info)

fs/cifs/file.c

@@ -110,10 +110,14 @@ cifs_open(struct inode *inode, struct file *file)
 			pCifsFile->netfid = netfid;
 			pCifsFile->pid = current->pid;
 			pCifsFile->pfile = file; /* needed for writepage */
+			write_lock(&file->f_owner.lock);
+			write_lock(&GlobalSMBSeslock);
 			list_add(&pCifsFile->tlist,&pTcon->openFileList);
 			pCifsInode = CIFS_I(file->f_dentry->d_inode);
 			if(pCifsInode->openFileList.next)
 				list_add(&pCifsFile->flist,&pCifsInode->openFileList);
+			write_unlock(&GlobalSMBSeslock);
+			write_unlock(&file->f_owner.lock);
 			if(file->f_flags & O_CREAT) {           
 				/* time to set mode which we can not set earlier due
 				 to problems creating new read-only files */
@@ -154,9 +158,11 @@ int reopen_files(struct cifsTconInfo * pTcon, struct nls_table * nlsinfo)
 	struct cifsFileInfo *open_file = NULL;
 	struct file * file = NULL;
 	struct list_head *tmp;
+	struct list_head *tmp1;
 
 /* list all files open on tree connection */
-	list_for_each(tmp, &pTcon->openFileList) {            
+	read_lock(&GlobalSMBSeslock);
+	list_for_each_safe(tmp, tmp1, &pTcon->openFileList) {            
 		open_file = list_entry(tmp,struct cifsFileInfo, flist);
 		if(open_file) {
 			if(open_file->search_resume_name) {
@@ -166,7 +172,9 @@ int reopen_files(struct cifsTconInfo * pTcon, struct nls_table * nlsinfo)
 			kfree(open_file);
 			if(file) {                
 				file->private_data = NULL;
+				read_unlock(&GlobalSMBSeslock);
 				rc = cifs_open(file->f_dentry->d_inode,file);
+				read_lock(&GlobalSMBSeslock);
 				if(rc) {
 					cFYI(1,("reconnecting file %s failed with %d",
 						file->f_dentry->d_name.name,rc));
@@ -177,6 +185,7 @@ int reopen_files(struct cifsTconInfo * pTcon, struct nls_table * nlsinfo)
 			} 
 		}
 	}
+	read_unlock(&GlobalSMBSeslock);
 	return rc;
 }
 
@@ -195,9 +204,11 @@ cifs_close(struct inode *inode, struct file *file)
 	cifs_sb = CIFS_SB(inode->i_sb);
 	pTcon = cifs_sb->tcon;
 	if (pSMBFile) {
+		write_lock(&file->f_owner.lock);
 		if(pSMBFile->flist.next)
 			list_del(&pSMBFile->flist);
 		list_del(&pSMBFile->tlist);
+		write_unlock(&file->f_owner.lock);
 		rc = CIFSSMBClose(xid, pTcon, pSMBFile->netfid);
 		if(pSMBFile->search_resume_name)
 			kfree(pSMBFile->search_resume_name);
@@ -206,6 +217,8 @@ cifs_close(struct inode *inode, struct file *file)
 	} else
 		rc = -EBADF;
 
+	if((rc ==0) && CIFS_I(inode)->write_behind_rc)
+		rc = CIFS_I(inode)->write_behind_rc;
 	FreeXid(xid);
 	return rc;
 }
@@ -407,6 +420,7 @@ cifs_partialpagewrite(struct page *page,unsigned from, unsigned to)
 	struct cifsInodeInfo *cifsInode;
 	struct cifsFileInfo *open_file = NULL;
 	struct list_head *tmp;
+	struct list_head *tmp1;
 	int xid;
 
 	xid = GetXid();
@@ -445,14 +459,17 @@ cifs_partialpagewrite(struct page *page,unsigned from, unsigned to)
 		
 
 	cifsInode = CIFS_I(mapping->host);
-	list_for_each(tmp, &cifsInode->openFileList) {            
+	read_lock(&GlobalSMBSeslock);
+	list_for_each_safe(tmp, tmp1, &cifsInode->openFileList) {            
 		open_file = list_entry(tmp,struct cifsFileInfo, flist);           
 	/* We could check if file is open for writing first */
 		if((open_file->pfile) && 
 		   ((open_file->pfile->f_flags & O_RDWR) || 
 			(open_file->pfile->f_flags & O_WRONLY))) {
+			read_unlock(&GlobalSMBSeslock);
 			bytes_written = cifs_write(open_file->pfile, write_data,
 					to-from, &offset);
+			read_lock(&GlobalSMBSeslock);
 		/* Does mm or vfs already set times? */
 			inode->i_atime = inode->i_mtime = CURRENT_TIME;
 			if ((bytes_written > 0) && (offset)) {
@@ -462,6 +479,7 @@ cifs_partialpagewrite(struct page *page,unsigned from, unsigned to)
 			}
 		}
 	}
+	read_unlock(&GlobalSMBSeslock);
 	if(open_file == NULL) {
 		cFYI(1,("No writeable filehandles for inode"));
 		rc = -EIO;
@@ -548,7 +566,8 @@ cifs_fsync(struct file *file, struct dentry *dentry, int datasync)
 		dentry->d_name.name, datasync));
 	
 	rc = filemap_fdatawrite(inode->i_mapping);
-
+	if(rc == 0)
+		CIFS_I(inode)->write_behind_rc = 0;
 	FreeXid(xid);
 	return rc;
 }
@@ -600,6 +619,9 @@ int cifs_flush(struct file *file)
 	/* filemapfdatawrite appears easier for the time being */
 
 	rc = filemap_fdatawrite(inode->i_mapping);
+	if(rc == 0) /* reset wb rc if we were able to write out dirty pages */
+		CIFS_I(inode)->write_behind_rc = 0;
+		
 	cFYI(1,("Flush inode %p file %p rc %d",inode,file,rc));
 
 	return rc;
@@ -678,9 +700,13 @@ static void cifs_copy_cache_pages(struct address_space *mapping,
 	while (bytes_read > 0) {
 		if(list_empty(pages))
 			break;
+
+		spin_lock(&mapping->page_lock);
 		page = list_entry(pages->prev, struct page, list);
 
 		list_del(&page->list);
+		spin_unlock(&mapping->page_lock);
+
 		if (add_to_page_cache(page, mapping, page->index, GFP_KERNEL)) {
 			page_cache_release(page);
 			cFYI(1,("Add page cache failed"));
@@ -739,12 +765,14 @@ cifs_readpages(struct file *file, struct address_space *mapping,
 	pagevec_init(&lru_pvec, 0);
 
 	for(i = 0;i<num_pages;) {
-
+		spin_lock(&mapping->page_lock);
 		if(list_empty(page_list)) {
 			break;
 		}
 		page = list_entry(page_list->prev, struct page, list);
 		offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
+	        spin_unlock(&mapping->page_lock);
+
 		/* for reads over a certain size could initiate async read ahead */
 
 		cFYI(0,("Read %d pages into cache at offset %ld ",
@@ -762,12 +790,15 @@ cifs_readpages(struct file *file, struct address_space *mapping,
 		if ((rc < 0) || (smb_read_data == NULL)) {
 			cFYI(1,("Read error in readpages: %d",rc));
 			/* clean up remaing pages off list */
+            
+			spin_lock(&mapping->page_lock);
 			while (!list_empty(page_list) && (i < num_pages)) {
 				page = list_entry(page_list->prev, struct page, list);
 				list_del(&page->list);
 			}
+			spin_unlock(&mapping->page_lock);
 			break;
-		} else if (bytes_read > 0){
+		} else if (bytes_read > 0) {
 			pSMBr = (struct smb_com_read_rsp *)smb_read_data;
 			cifs_copy_cache_pages(mapping, page_list, bytes_read,
 				smb_read_data + 4 /* RFC1000 hdr */ +

fs/cifs/inode.c

@@ -53,10 +53,6 @@ cifs_get_inode_info_unix(struct inode **pinode,
 	/* dump_mem("\nUnixQPathInfo return data", &findData, sizeof(findData)); */
 	if (rc) {
 		if (rc == -EREMOTE) {
-/* rc = *//* CIFSGetDFSRefer(xid, pTcon->ses, search_path,
-	&referrals,
-	&num_referrals,
-	cifs_sb->local_nls); */
 			tmp_path =
 			    kmalloc(strnlen
 				    (pTcon->treeName,
@@ -180,11 +176,6 @@ cifs_get_inode_info(struct inode **pinode,
 	/* dump_mem("\nQPathInfo return data",&findData, sizeof(findData)); */
 	if (rc) {
 		if (rc == -EREMOTE) {
-			/* BB add call to new func rc = GetDFSReferral(); */
-/* rc = *//* CIFSGetDFSRefer(xid, pTcon->ses, search_path,
-	&referrals,
-	&num_referrals,
-	cifs_sb->local_nls); */
 			tmp_path =
 			    kmalloc(strnlen
 				    (pTcon->treeName,

fs/cifs/link.c

@@ -113,6 +113,9 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
 	/* BB Should we be using page symlink ops here? */
 
 	if (rc == 0) {
+
+/* BB Add special case check for Samba DFS symlinks */
+
 		target_path[PATH_MAX-1] = 0;
 		rc = vfs_follow_link(nd, target_path);
 	}
@@ -186,7 +189,10 @@ cifs_readlink(struct dentry *direntry, char *pBuffer, int buflen)
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *pTcon;
 	char *full_path = NULL;
+	char *tmp_path =  NULL;
 	char * tmpbuffer;
+	unsigned char * referrals = NULL;
+	int num_referrals = 0;
 	int len;
 	__u16 fid;
 
@@ -206,6 +212,7 @@ cifs_readlink(struct dentry *direntry, char *pBuffer, int buflen)
 		FreeXid(xid);
 		return -ENOMEM;
 	}
+
 /* BB add read reparse point symlink code and Unix extensions symlink code here BB */
 	if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)
 		rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
@@ -224,8 +231,36 @@ cifs_readlink(struct dentry *direntry, char *pBuffer, int buflen)
 			if(CIFSSMBClose(xid, pTcon, fid)) {
 				cFYI(1,("Error closing junction point (open for ioctl)"));
 			}
+			if(rc == -EIO) {
+				/* Query if DFS Junction */
+				tmp_path =
+					kmalloc(MAX_TREE_SIZE + MAX_PATHCONF + 1,
+						GFP_KERNEL);
+				if (tmp_path) {
+					strncpy(tmp_path, pTcon->treeName, MAX_TREE_SIZE);
+					strncat(tmp_path, full_path, MAX_PATHCONF);
+					rc = get_dfs_path(xid, pTcon->ses, tmp_path,
+						cifs_sb->local_nls, &num_referrals, &referrals);
+					cFYI(1,("Get DFS for %s rc = %d ",tmp_path, rc));
+					if((num_referrals == 0) && (rc == 0))
+						rc = -EACCES;
+					else {
+						cFYI(1,("num referral: %d",num_referrals));
+						if(referrals) {
+							cFYI(1,("referral string: %s ",referrals));
+							strncpy(tmpbuffer, referrals, len-1);
+						}
 					}
 
+					kfree(tmp_path);
+					if(referrals) {
+						kfree(referrals);
+					}
+				}
+				/* BB add code like else decode referrals then memcpy to
+				  tmpbuffer and free referrals string array BB */
+			}
+		}
 	}
 	/* BB Anything else to do to handle recursive links? */
 	/* BB Should we be using page ops here? */
@@ -238,10 +273,12 @@ cifs_readlink(struct dentry *direntry, char *pBuffer, int buflen)
 		      rc));
 	}
 
-	if (tmpbuffer)
+	if (tmpbuffer) {
 		kfree(tmpbuffer);
-	if (full_path)
+	}
+	if (full_path) {
 		kfree(full_path);
+	}
 	FreeXid(xid);
 	return rc;
 }