Add resume key support for readdir to workaround Windows 2000 and XP server

problem.  Update oplock handling code.  Reduce excessive stack usage in 
link.c

fs/cifs/CHANGES

+Version 0.72
+------------
+Add resume key support to search (readdir) code to workaround
+Windows bug.  Add /proc/fs/cifs/LookupCacheEnable which
+allows disabling caching of attribute information for
+lookups.
+
+Version 0.71
+------------
+Add more oplock handling (distributed caching code).  Remove
+dead code.  Remove excessive stack space utilization from
+symlink routines.
+
 Version 0.70
 ------------
 Fix oops in get dfs referral (triggered when null path sent in to

fs/cifs/cifs_debug.c

@@ -185,6 +185,8 @@ static read_proc_t cifsFYI_read;
 static write_proc_t cifsFYI_write;
 static read_proc_t oplockEnabled_read;
 static write_proc_t oplockEnabled_write;
+static read_proc_t lookupFlag_read;
+static write_proc_t lookupFlag_write;
 static read_proc_t traceSMB_read;
 static write_proc_t traceSMB_write;
 static read_proc_t multiuser_mount_read;
@@ -243,6 +245,12 @@ cifs_proc_init(void)
 	if (pde)
 		pde->write_proc = extended_security_write;
 
+	pde =
+	create_proc_read_entry("LookupCacheEnable", 0, proc_fs_cifs,
+		lookupFlag_read, 0);
+	if (pde)
+		pde->write_proc = lookupFlag_write;
+
 	pde =
 	    create_proc_read_entry("NTLMV2Enabled", 0, proc_fs_cifs,
 				   ntlmv2_enabled_read, 0);
@@ -353,6 +361,44 @@ oplockEnabled_write(struct file *file, const char *buffer,
 	return count;
 }
 
+static int
+lookupFlag_read(char *page, char **start, off_t off,
+		   int count, int *eof, void *data)
+{
+	int len;
+
+	len = sprintf(page, "%d\n", lookupCacheEnabled);
+
+	len -= off;
+	*start = page + off;
+
+	if (len > count)
+		len = count;
+	else
+		*eof = 1;
+
+	if (len < 0)
+		len = 0;
+
+	return len;
+}
+static int
+lookupFlag_write(struct file *file, const char *buffer,
+		    unsigned long count, void *data)
+{
+	char c;
+	int rc;
+
+	rc = get_user(c, buffer);
+	if (rc)
+		return rc;
+	if (c == '0' || c == 'n' || c == 'N')
+		lookupCacheEnabled = 0;
+	else if (c == '1' || c == 'y' || c == 'Y')
+		lookupCacheEnabled = 1;
+
+	return count;
+}
 static int
 traceSMB_read(char *page, char **start, off_t off, int count,
 	      int *eof, void *data)

fs/cifs/cifsfs.c

@@ -48,11 +48,13 @@ int cifsFYI = 0;
 int cifsERROR = 1;
 int traceSMB = 0;
 unsigned int oplockEnabled = 0;
+unsigned int lookupCacheEnabled = 1;
 unsigned int multiuser_mount = 0;
 unsigned int extended_security = 0;
 unsigned int ntlmv2_support = 0;
 unsigned int sign_CIFS_PDUs = 0;
 unsigned int CIFSMaximumBufferSize = CIFS_MAX_MSGSIZE;
+struct task_struct * oplockThread = NULL;
 
 extern int cifs_mount(struct super_block *, struct cifs_sb_info *, char *,
 			char *);
@@ -175,6 +177,7 @@ static int cifs_permission(struct inode * inode, int mask)
 static kmem_cache_t *cifs_inode_cachep;
 kmem_cache_t *cifs_req_cachep;
 kmem_cache_t *cifs_mid_cachep;
+kmem_cache_t *cifs_oplock_cachep;
 
 static struct inode *
 cifs_alloc_inode(struct super_block *sb)
@@ -390,10 +393,17 @@ int
 cifs_init_mids(void)
 {
 	cifs_mid_cachep = kmem_cache_create("cifs_mpx_ids",
-					    sizeof (struct mid_q_entry), 0,
-					    SLAB_HWCACHE_ALIGN, NULL, NULL);
+				sizeof (struct mid_q_entry), 0,
+				SLAB_HWCACHE_ALIGN, NULL, NULL);
 	if (cifs_mid_cachep == NULL)
 		return -ENOMEM;
+	cifs_oplock_cachep = kmem_cache_create("cifs_oplock_structs",
+				sizeof (struct oplock_q_entry), 0,
+				SLAB_HWCACHE_ALIGN, NULL, NULL);
+	if (cifs_oplock_cachep == NULL) {
+		kmem_cache_destroy(cifs_mid_cachep);
+		return -ENOMEM;
+	}
 
 	return 0;
 }
@@ -404,6 +414,49 @@ cifs_destroy_mids(void)
 	if (kmem_cache_destroy(cifs_mid_cachep))
 		printk(KERN_WARNING
 		       "cifs_destroy_mids: error not all structures were freed\n");
+	if (kmem_cache_destroy(cifs_oplock_cachep))
+		printk(KERN_WARNING
+		       "error not all oplock structures were freed\n");}
+
+static int cifs_oplock_thread(void * dummyarg)
+{
+	struct list_head * tmp;
+	struct oplock_q_entry * oplock_item;
+	struct file * pfile;
+	struct cifsTconInfo *pTcon;
+	int rc;
+
+	daemonize("cifsoplockd");
+	allow_signal(SIGKILL);
+
+	oplockThread = current;
+	while (1) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		schedule_timeout(100*HZ);
+		/* 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,
+							       qhead);
+			if(oplock_item) {
+				pTcon = oplock_item->tcon;
+				pfile = oplock_item->file_to_flush;
+				cFYI(1,("process item on queue"));/* BB remove */
+				DeleteOplockQEntry(oplock_item);
+				write_unlock(&GlobalMid_Lock);
+				rc = filemap_fdatawrite(pfile->f_dentry->d_inode->i_mapping);
+				cFYI(1,("Oplock flush file %p rc %d",pfile,rc));
+				/* send oplock break */
+				write_lock(&GlobalMid_Lock);
+			} else
+				break;
+			cFYI(1,("next time through list")); /* BB remove */
+		}
+		write_unlock(&GlobalMid_Lock);
+		cFYI(1,("next time through while loop")); /* BB remove */
+	}
 }
 
 static int __init
@@ -416,7 +469,7 @@ init_cifs(void)
 	INIT_LIST_HEAD(&GlobalServerList);	/* BB not implemented yet */
 	INIT_LIST_HEAD(&GlobalSMBSessionList);
 	INIT_LIST_HEAD(&GlobalTreeConnectionList);
-
+	INIT_LIST_HEAD(&GlobalOplock_Q);
 /*
  *  Initialize Global counters
  */
@@ -437,9 +490,11 @@ init_cifs(void)
 			rc = cifs_init_request_bufs();
 			if (!rc) {
 				rc = register_filesystem(&cifs_fs_type);
-				if (!rc)
-					return rc;	/* Success */
-				else
+				if (!rc) {                
+					kernel_thread(cifs_oplock_thread, NULL, 
+						CLONE_FS | CLONE_FILES | CLONE_VM);
+					return rc; /* Success */
+				} else
 					cifs_destroy_request_bufs();
 			}
 			cifs_destroy_mids();
@@ -459,10 +514,12 @@ exit_cifs(void)
 #if CONFIG_PROC_FS
 	cifs_proc_clean();
 #endif
-    	unregister_filesystem(&cifs_fs_type);
+	unregister_filesystem(&cifs_fs_type);
 	cifs_destroy_inodecache();
 	cifs_destroy_mids();
 	cifs_destroy_request_bufs();
+	if(oplockThread)
+		send_sig(SIGKILL, oplockThread, 1);
 }
 
 MODULE_AUTHOR("Steve French <sfrench@us.ibm.com>");

fs/cifs/cifsglob.h

@@ -207,6 +207,9 @@ struct cifsFileInfo {
     struct file * pfile; /* needed for writepage */
 	int endOfSearch:1;	/* we have reached end of search */
 	int closePend:1;	/* file is marked to close */
+    char * search_resume_name;
+    unsigned int resume_name_length;
+    __u32 resume_key;
 };
 
 /*
@@ -221,7 +224,8 @@ struct cifsInodeInfo {
 	atomic_t inUse;	 /* num concurrent users (local openers cifs) of file*/
 	unsigned long time;	/* jiffies of last update/check of inode */
 	int clientCanCacheRead:1; /* read oplock */
-    int clientCanCacheAll:1;  /* read and writebehind oplock */
+	int clientCanCacheAll:1;  /* read and writebehind oplock */
+	int oplockPending:1;
 	struct inode vfs_inode;
 };
 
@@ -251,14 +255,20 @@ struct mid_q_entry {
 	int midState;	/* wish this were enum but can not pass to wait_event */
 };
 
+struct oplock_q_entry {
+	struct list_head qhead;
+	struct file * file_to_flush;
+	struct cifsTconInfo * tcon; 
+};
+
 #define   MID_FREE 0
 #define   MID_REQUEST_ALLOCATED 1
 #define   MID_REQUEST_SUBMITTED 2
 #define   MID_RESPONSE_RECEIVED 4
 
-struct servers_not_supported {	/* @z4a */
-	struct servers_not_supported *next1;	/* @z4a */
-	char server_Name[SERVER_NAME_LEN_WITH_NULL];	/* @z4a */
+struct servers_not_supported { /* @z4a */
+	struct servers_not_supported *next1;  /* @z4a */
+	char server_Name[SERVER_NAME_LEN_WITH_NULL]; /* @z4a */
 	/* Server Names in SMB protocol are 15 chars + X'20'  */
 	/*   in 16th byte...                      @z4a        */
 };
@@ -301,6 +311,8 @@ GLOBAL_EXTERN struct list_head GlobalSMBSessionList;
 GLOBAL_EXTERN struct list_head GlobalTreeConnectionList;
 GLOBAL_EXTERN rwlock_t GlobalSMBSeslock;  /* protects list inserts on 3 above */
 
+GLOBAL_EXTERN struct list_head GlobalOplock_Q;
+
 /*
  * Global transaction id (XID) information
  */
@@ -327,6 +339,7 @@ GLOBAL_EXTERN unsigned int multiuser_mount;	/* if enabled allows new sessions
 				have the uid/password or Kerberos credential 
 				or equivalent for current user */
 GLOBAL_EXTERN unsigned int oplockEnabled;
+GLOBAL_EXTERN unsigned int lookupCacheEnabled;
 GLOBAL_EXTERN unsigned int extended_security;	/* if on, session setup sent 
 				with more secure ntlmssp2 challenge/resp */
 GLOBAL_EXTERN unsigned int ntlmv2_support;  /* better optional password hash */

fs/cifs/cifspdu.h

@@ -38,6 +38,7 @@
 #define SMB_COM_WRITE_ANDX            0x2F
 #define SMB_COM_TRANSACTION2	      0x32
 #define SMB_COM_TRANSACTION2_SECONDARY 0x33
+#define SMB_COM_FIND_CLOSE2           0x34
 #define SMB_COM_TREE_DISCONNECT       0x71
 #define SMB_COM_NEGOTIATE             0x72
 #define SMB_COM_SESSION_SETUP_ANDX    0x73
@@ -584,7 +585,7 @@ typedef union smb_com_tree_disconnect {	/* as an altetnative can use flag on tre
 
 typedef struct smb_com_close_req {
 	struct smb_hdr hdr;	/* wct = 3 */
-	__u16 FileID;		/* target file attributes */
+	__u16 FileID;
 	__u32 LastWriteTime;	/* should be zero */
 	__u16 ByteCount;	/* 0 */
 } CLOSE_REQ;
@@ -594,6 +595,12 @@ typedef struct smb_com_close_rsp {
 	__u16 ByteCount;	/* bct = 0 */
 } CLOSE_RSP;
 
+typedef struct smb_com_findclose_req {
+	struct smb_hdr hdr; /* wct = 1 */
+	__u16 FileID;
+	__u16 ByteCount;    /* 0 */
+} FINDCLOSE_REQ;
+
 /* OpenFlags */
 #define REQ_OPLOCK         0x00000002
 #define REQ_BATCHOPLOCK    0x00000004
@@ -1152,7 +1159,7 @@ typedef struct smb_com_transaction2_fnext_req {
 	__u16 InformationLevel;
 	__u32 ResumeKey;
 	__u16 SearchFlags;
-	char ResumeFileName[1];	/* will be null string actually since we set bit 3 - resume from previous ending place */
+	char ResumeFileName[1];
 } TRANSACTION2_FNEXT_REQ;
 
 typedef struct smb_com_transaction2_fnext_rsp {
@@ -1509,7 +1516,7 @@ typedef struct {
 	__u32 ExtFileAttributes;
 	__u32 FileNameLength;
 	char FileName[1];
-} FILE_DIRECTORY_INFO;		/* level 257 FF response data area */
+} FILE_DIRECTORY_INFO;   /* level 257 FF response data area */
 
 struct gea {
 	unsigned char cbName;

fs/cifs/cifsproto.h

@@ -57,6 +57,8 @@ extern void header_assemble(struct smb_hdr *, char /* command */ ,
 			const struct cifsTconInfo *, int
 			/* length of fixed section (word count) in two byte units  */
 			);
+struct oplock_q_entry * AllocOplockQEntry(struct file *,struct cifsTconInfo *);
+void DeleteOplockQEntry(struct oplock_q_entry *);
 extern struct timespec cifs_NTtimeToUnix(u64 /* utc nanoseconds since 1601 */ );
 extern u64 cifs_UnixTimeToNT(struct timespec);
 extern void RevUcode_to_Ucode(char *revUnicode, char *UnicodeName);
@@ -104,9 +106,13 @@ extern int CIFSFindFirst(const int xid, struct cifsTconInfo *tcon,
 extern int CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
 			FILE_DIRECTORY_INFO * findData,
 			T2_FNEXT_RSP_PARMS * findParms,
-			const __u16 searchHandle, const __u32 resumeKey,
+			const __u16 searchHandle, char * resume_name,
+			int name_length, __u32 resume_key,
 			int *UnicodeFlag, int *pUnixFlag);
 
+extern int CIFSFindClose(const int, struct cifsTconInfo *tcon,
+			const __u16 search_handle);
+
 extern int CIFSSMBQPathInfo(const int xid, struct cifsTconInfo *tcon,
 			const unsigned char *searchName,
 			FILE_ALL_INFO * findData,

fs/cifs/cifssmb.c

@@ -1449,7 +1449,7 @@ CIFSFindFirst(const int xid, struct cifsTconInfo *tcon,
 	    cpu_to_le16(ATTR_READONLY | ATTR_HIDDEN | ATTR_SYSTEM |
 			ATTR_DIRECTORY);
 	pSMB->SearchCount = cpu_to_le16(CIFS_MAX_MSGSIZE / sizeof (FILE_DIRECTORY_INFO));	/* should this be shrunk even more ? */
-	pSMB->SearchFlags = cpu_to_le16(CIFS_SEARCH_CLOSE_AT_END);
+	pSMB->SearchFlags = cpu_to_le16(CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME);
 
 	/* test for Unix extensions */
 	if (tcon->ses->capabilities & CAP_UNIX) {
@@ -1496,9 +1496,9 @@ CIFSFindFirst(const int xid, struct cifsTconInfo *tcon,
 
 int
 CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
-	     FILE_DIRECTORY_INFO * findData,
-	     T2_FNEXT_RSP_PARMS * findParms, const __u16 searchHandle,
-	     __u32 resumeKey, int *pUnicodeFlag, int *pUnixFlag)
+		FILE_DIRECTORY_INFO * findData, T2_FNEXT_RSP_PARMS * findParms,
+		const __u16 searchHandle, char * resume_file_name, int name_len,
+		__u32 resume_key, int *pUnicodeFlag, int *pUnixFlag)
 {
 /* level 257 SMB_ */
 	TRANSACTION2_FNEXT_REQ *pSMB = NULL;
@@ -1508,6 +1508,9 @@ CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
 	int bytes_returned;
 
 	cFYI(1, ("In FindNext"));
+	if(resume_file_name == NULL) {
+		return -EIO;
+	}
 	rc = smb_init(SMB_COM_TRANSACTION2, 15, tcon, (void **) &pSMB,
 		      (void **) &pSMBr);
 	if (rc)
@@ -1530,9 +1533,6 @@ CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
 	pSMB->SetupCount = 1;
 	pSMB->Reserved3 = 0;
 	pSMB->SubCommand = cpu_to_le16(TRANS2_FIND_NEXT);
-	pSMB->ByteCount = pSMB->TotalParameterCount + 1 /* pad */ ;
-	pSMB->TotalParameterCount = cpu_to_le16(pSMB->TotalParameterCount);
-	pSMB->ParameterCount = pSMB->TotalParameterCount;
 	pSMB->SearchHandle = searchHandle;	/* always kept as le */
 	findParms->SearchCount = 0;	/* set to zero in case of error */
 	pSMB->SearchCount =
@@ -1546,10 +1546,19 @@ CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
 		    cpu_to_le16(SMB_FIND_FILE_DIRECTORY_INFO);
 		*pUnixFlag = FALSE;
 	}
-	pSMB->ResumeKey = resumeKey;	/* always kept as le */
+	pSMB->ResumeKey = resume_key;
 	pSMB->SearchFlags =
-	    cpu_to_le16(CIFS_SEARCH_CLOSE_AT_END |
-			CIFS_SEARCH_CONTINUE_FROM_LAST);
+	    cpu_to_le16(CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME);
+	/* BB add check to make sure we do not cross end of smb */
+	if(name_len < CIFS_MAX_MSGSIZE) {
+		memcpy(pSMB->ResumeFileName, resume_file_name, name_len);
+		pSMB->ByteCount += name_len;
+	}
+	pSMB->TotalParameterCount += name_len;
+	pSMB->ByteCount = pSMB->TotalParameterCount + 1 /* pad */ ;
+	pSMB->TotalParameterCount = cpu_to_le16(pSMB->TotalParameterCount);
+	pSMB->ParameterCount = pSMB->TotalParameterCount;
+	/* BB improve error handling here */
 	pSMB->hdr.smb_buf_length += pSMB->ByteCount;
 	pSMB->ByteCount = cpu_to_le16(pSMB->ByteCount);
 
@@ -1585,6 +1594,33 @@ CIFSFindNext(const int xid, struct cifsTconInfo *tcon,
 	return rc;
 }
 
+int
+CIFSFindClose(const int xid, struct cifsTconInfo *tcon, const __u16 searchHandle)
+{
+	int rc = 0;
+	FINDCLOSE_REQ *pSMB = NULL;
+	CLOSE_RSP *pSMBr = NULL;
+	int bytes_returned;
+	cFYI(1, ("In CIFSSMBFindClose"));
+
+	rc = smb_init(SMB_COM_FIND_CLOSE2, 1, tcon, (void **) &pSMB,
+		      (void **) &pSMBr);
+	if (rc)
+		return rc;
+
+	pSMB->FileID = searchHandle;
+	pSMB->ByteCount = 0;
+	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+			 (struct smb_hdr *) pSMBr, &bytes_returned, 0);
+	if (rc) {
+		cERROR(1, ("Send error in FindClose = %d", rc));
+	}
+	if (pSMB)
+		buf_release(pSMB);
+
+	return rc;
+}
+
 int
 CIFSGetDFSRefer(const int xid, struct cifsSesInfo *ses,
 		const unsigned char *searchName,

fs/cifs/connect.c

@@ -850,8 +850,7 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 			init_waitqueue_head(&srvTcp->response_q);
 			INIT_LIST_HEAD(&srvTcp->pending_mid_q);
 			srvTcp->tcpStatus = CifsGood;
-			kernel_thread((void *) (void *)
-				      cifs_demultiplex_thread, srvTcp,
+			kernel_thread((void *)(void *)cifs_demultiplex_thread, srvTcp,
 				      CLONE_FS | CLONE_FILES | CLONE_VM);
 		}
 	}

fs/cifs/inode.c

@@ -450,10 +450,10 @@ cifs_rename(struct inode *source_inode, struct dentry *source_direntry,
 	cifs_sb_source = CIFS_SB(source_inode->i_sb);
 	pTcon = cifs_sb_source->tcon;
 
-	if (pTcon != cifs_sb_target->tcon) {    
+	if (pTcon != cifs_sb_target->tcon) {
+		FreeXid(xid);    
 		return -EXDEV;	/* BB actually could be allowed if same server, but
                      different share. Might eventually add support for this */
-        	FreeXid(xid);
 	}
 
 	fromName = build_path_from_dentry(source_direntry);
@@ -471,7 +471,7 @@ cifs_rename(struct inode *source_inode, struct dentry *source_direntry,
 	if (toName)
 		kfree(toName);
 
-    FreeXid(xid);
+	FreeXid(xid);
 	return rc;
 }
 
@@ -500,15 +500,15 @@ cifs_revalidate(struct dentry *direntry)
 
 	if (time_before(jiffies, cifsInode->time + HZ)) {
 	    if((S_ISREG(direntry->d_inode->i_mode) == 0) || 
-              (direntry->d_inode->i_nlink == 1)) {
-		    if (full_path)
-			    kfree(full_path);
-		    FreeXid(xid);
-		    return rc;
-        } else {
-            cFYI(1,("Have to revalidate file due to hardlinks"));
-        }
-            
+			(direntry->d_inode->i_nlink == 1) || 
+			(lookupCacheEnabled == 0)) {
+			if (full_path)
+				kfree(full_path);
+			FreeXid(xid);
+			return rc;
+		} else {
+			cFYI(1,("Have to revalidate file due to hardlinks"));
+		}            
 	}
 
 	if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)

fs/cifs/link.c

@@ -82,7 +82,7 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
 	int rc = -EACCES;
 	int xid;
 	char *full_path = NULL;
-	char target_path[257];
+	char * target_path;
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *pTcon;
 
@@ -91,7 +91,11 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
 	cFYI(1, ("Full path: %s inode = 0x%p", full_path, inode));
 	cifs_sb = CIFS_SB(inode->i_sb);
 	pTcon = cifs_sb->tcon;
-
+	target_path = kmalloc(PATH_MAX, GFP_KERNEL);
+	if(target_path == NULL) {
+		FreeXid(xid);
+		return -ENOMEM;
+	}
 	/* can not call the following line due to EFAULT in vfs_readlink which is presumably expecting a user space buffer */
 	/* length = cifs_readlink(direntry,target_path, sizeof(target_path) - 1);    */
 
@@ -99,7 +103,7 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
 	if (pTcon->ses->capabilities & CAP_UNIX)
 		rc = CIFSSMBUnixQuerySymLink(xid, pTcon, full_path,
 					     target_path,
-					     sizeof (target_path) - 1,
+					     PATH_MAX-1,
 					     cifs_sb->local_nls);
 	else {
 		/* rc = CIFSSMBQueryReparseLinkInfo */
@@ -109,11 +113,13 @@ cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
 	/* BB Should we be using page symlink ops here? */
 
 	if (rc == 0) {
-		target_path[256] = 0;
+		target_path[PATH_MAX-1] = 0;
 		rc = vfs_follow_link(nd, target_path);
 	}
 	/* else EACCESS */
 
+	if (target_path)
+		kfree(target_path);
 	if (full_path)
 		kfree(full_path);
 	FreeXid(xid);
@@ -180,7 +186,8 @@ cifs_readlink(struct dentry *direntry, char *pBuffer, int buflen)
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *pTcon;
 	char *full_path = NULL;
-	char tmpbuffer[256];
+	char * tmpbuffer;
+	int len;
 	__u16 fid;
 
 	xid = GetXid();
@@ -190,20 +197,28 @@ cifs_readlink(struct dentry *direntry, char *pBuffer, int buflen)
 	cFYI(1,
 	     ("Full path: %s inode = 0x%p pBuffer = 0x%p buflen = %d",
 	      full_path, inode, pBuffer, buflen));
-
+	if(buflen > PATH_MAX)
+		len = PATH_MAX;
+	else
+		len = buflen;
+	tmpbuffer = kmalloc(len,GFP_KERNEL);   
+	if(tmpbuffer == NULL) {
+		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,
-					tmpbuffer,
-					sizeof (tmpbuffer) - 1,
-					cifs_sb->local_nls);
+				tmpbuffer,
+				len - 1,
+				cifs_sb->local_nls);
 	else {
 		rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_OPEN, GENERIC_READ,
 				OPEN_REPARSE_POINT,&fid, &oplock, cifs_sb->local_nls);
 		if(!rc) {
 			rc = CIFSSMBQueryReparseLinkInfo(xid, pTcon, full_path,
 				tmpbuffer,
-				sizeof(tmpbuffer) - 1, 
+				len - 1, 
 				fid,
 				cifs_sb->local_nls);
 			if(CIFSSMBClose(xid, pTcon, fid)) {
@@ -216,15 +231,15 @@ cifs_readlink(struct dentry *direntry, char *pBuffer, int buflen)
 	/* BB Should we be using page ops here? */
 
 	/* BB null terminate returned string in pBuffer? BB */
-	if (buflen > sizeof (tmpbuffer))
-		buflen = sizeof (tmpbuffer);
 	if (rc == 0) {
-		rc = vfs_readlink(direntry, pBuffer, buflen, tmpbuffer);
+		rc = vfs_readlink(direntry, pBuffer, len, tmpbuffer);
 		cFYI(1,
 		     ("vfs_readlink called from cifs_readlink returned %d",
 		      rc));
 	}
 
+	if (tmpbuffer)
+		kfree(tmpbuffer);
 	if (full_path)
 		kfree(full_path);
 	FreeXid(xid);

fs/cifs/misc.c

@@ -27,6 +27,7 @@
 #include "cifs_debug.h"
 
 extern kmem_cache_t *cifs_req_cachep;
+extern struct task_struct * oplockThread;
 
 __u16 GlobalMid;		/* multiplex id - rotating counter */
 
@@ -336,6 +337,7 @@ is_valid_oplock_break(struct smb_hdr *buf)
 			list_for_each(tmp1,&tcon->openFileList){
 				netfile = list_entry(tmp1,struct cifsFileInfo,tlist);
 				if(pSMB->Fid == netfile->netfid) {
+					struct cifsInodeInfo *pCifsInode;
 			/* BB Add following logic: 
 			  2) look up inode from tcon->openFileList->file->f_dentry->d_inode
 			  3) flush dirty pages and cached byte range locks and mark inode
@@ -345,6 +347,15 @@ is_valid_oplock_break(struct smb_hdr *buf)
 			  6) send oplock break response to server */
 					read_unlock(&GlobalSMBSeslock);
 					cFYI(1,("Matching file id, processing oplock break"));
+					pCifsInode = 
+						CIFS_I(netfile->pfile->f_dentry->d_inode);
+					pCifsInode->clientCanCacheAll = FALSE;
+					if(pSMB->OplockLevel == 0)
+						pCifsInode->clientCanCacheRead = FALSE;
+					pCifsInode->oplockPending = TRUE;
+					AllocOplockQEntry(netfile->pfile, tcon);
+                    cFYI(1,("about to wake up oplock thd"));
+					wake_up_process(oplockThread);               
 					return TRUE;
 				}
 			}

fs/cifs/transport.c

@@ -32,6 +32,7 @@
 #include "cifs_debug.h"
 
 extern kmem_cache_t *cifs_mid_cachep;
+extern kmem_cache_t *cifs_oplock_cachep;
 
 struct mid_q_entry *
 AllocMidQEntry(struct smb_hdr *smb_buffer, struct cifsSesInfo *ses)
@@ -95,6 +96,39 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
 	kmem_cache_free(cifs_mid_cachep, midEntry);
 }
 
+struct oplock_q_entry *
+AllocOplockQEntry(struct file * file, struct cifsTconInfo * tcon)
+{
+	struct oplock_q_entry *temp;
+	if ((file == NULL) || (tcon == NULL)) {
+		cERROR(1, ("Null parms passed to AllocOplockQEntry"));
+		return NULL;
+	}
+	temp = (struct oplock_q_entry *) kmem_cache_alloc(cifs_oplock_cachep,
+						       SLAB_KERNEL);
+	if (temp == NULL)
+		return temp;
+	else {
+		temp->file_to_flush = file;
+		temp->tcon = tcon;
+		write_lock(&GlobalMid_Lock);
+		list_add_tail(&temp->qhead, &GlobalOplock_Q);
+		write_unlock(&GlobalMid_Lock);
+	}
+    return temp;
+
+}
+
+void DeleteOplockQEntry(struct oplock_q_entry * oplockEntry)
+{
+	/* BB add spinlock to protect midq for each session BB */
+	write_lock(&GlobalMid_Lock); 
+    /* should we check if list empty first? */
+	list_del(&oplockEntry->qhead);
+	write_unlock(&GlobalMid_Lock);
+	kmem_cache_free(cifs_oplock_cachep, oplockEntry);
+}
+
 int
 smb_send(struct socket *ssocket, struct smb_hdr *smb_buffer,
 	 unsigned int smb_buf_length, struct sockaddr *sin)