Fix for file size handling for locally cached files.

fs/cifs/CHANGES

+Version 0.86
+------------
+Fix oops on empty file readahead.  Fix for file size handling for locally cached files.
 Version 0.85
 ------------
 Fix oops in mkdir when server fails to return inode info. Fix oops in reopen_files

fs/cifs/cifsfs.c

@@ -201,10 +201,11 @@ cifs_alloc_inode(struct super_block *sb)
 	cifs_inode->cifsAttrs = 0x20;	/* default */
 	atomic_set(&cifs_inode->inUse, 0);
 	cifs_inode->time = 0;
-	if(oplockEnabled) {
-		cifs_inode->clientCanCacheRead = 1;
-		cifs_inode->clientCanCacheAll = 1;
-	}
+	/* Until the file is open and we have gotten oplock
+	info back from the server, can not assume caching of
+	file data or metadata */
+	cifs_inode->clientCanCacheRead = FALSE;
+	cifs_inode->clientCanCacheAll = FALSE;
 	INIT_LIST_HEAD(&cifs_inode->openFileList);
 	return &cifs_inode->vfs_inode;
 }

fs/cifs/cifspdu.h

@@ -633,6 +633,12 @@ typedef struct smb_com_open_req {	/* also handles create */
 	char fileName[1];
 } OPEN_REQ;
 
+/* open response: oplock levels */
+#define OPLOCK_NONE  	 0
+#define OPLOCK_EXCLUSIVE 1
+#define OPLOCK_BATCH	 2
+#define OPLOCK_READ	 3  /* level 2 oplock */
+
 typedef struct smb_com_open_rsp {
 	struct smb_hdr hdr;	/* wct = 34 BB */
 	__u8 AndXCommand;

fs/cifs/dir.c

@@ -144,7 +144,7 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 	full_path = build_path_from_dentry(direntry);
 
 	if(nd) { 
-		cFYI(1,("In create nd flags = 0x%x for %s",nd->flags,full_path));
+		cFYI(1,("In create for inode %p dentry->inode %p nd flags = 0x%x for %s",inode, direntry->d_inode, nd->flags,full_path));
 
 		if ((nd->intent.open.flags & O_ACCMODE) == O_RDONLY)
                 	desiredAccess = GENERIC_READ;
@@ -165,6 +165,8 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 	if (rc) {
 		cFYI(1, ("cifs_create returned 0x%x ", rc));
 	} else {
+	/* BB for case of overwriting existing file can we use the inode that was
+		 passed in rather than creating new one?? */
 		if (pTcon->ses->capabilities & CAP_UNIX)
 			rc = cifs_get_inode_info_unix(&newinode, full_path,
 						      inode->i_sb);
@@ -195,8 +197,15 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 				write_lock(&GlobalSMBSeslock);
 				list_add(&pCifsFile->tlist,&pTcon->openFileList);
 				pCifsInode = CIFS_I(newinode);
-				if(pCifsInode)
+				if(pCifsInode) {
 					list_add(&pCifsFile->flist,&pCifsInode->openFileList);
+					if(oplock == OPLOCK_EXCLUSIVE) {
+						pCifsInode->clientCanCacheAll = TRUE;
+						pCifsInode->clientCanCacheRead = TRUE;
+						cFYI(1,("Exclusive Oplock granted on inode %p",newinode));
+					} else if(oplock == OPLOCK_READ)
+						pCifsInode->clientCanCacheRead = TRUE;
+				}
 				write_unlock(&GlobalSMBSeslock);
 				if (cifs_sb->tcon->ses->capabilities & CAP_UNIX)                
 					CIFSSMBUnixSetPerms(xid, pTcon, full_path, inode->i_mode,

fs/cifs/file.c

@@ -50,6 +50,7 @@ cifs_open(struct inode *inode, struct file *file)
 	int desiredAccess = 0x20197;
 	int disposition = FILE_OPEN;
 	__u16 netfid;
+	FILE_ALL_INFO * buf = NULL;
 
 	xid = GetXid();
 
@@ -117,11 +118,12 @@ cifs_open(struct inode *inode, struct file *file)
 
 	/* BB pass O_SYNC flag through on file attributes .. BB */
 
-	/* BB add code to refresh inode by passing in file_info buf on open 
+	/* Also refresh inode by passing in file_info buf returned by SMBOpen 
 	   and calling get_inode_info with returned buf (at least 
 	   helps non-Unix server case */
+        buf = kmalloc(sizeof(FILE_ALL_INFO),GFP_KERNEL);
 	rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess,
-			CREATE_NOT_DIR, &netfid, &oplock, NULL, cifs_sb->local_nls);
+			CREATE_NOT_DIR, &netfid, &oplock, buf, cifs_sb->local_nls);
 	if (rc) {
 		cFYI(1, ("cifs_open returned 0x%x ", rc));
 		cFYI(1, ("oplock: %d ", oplock));	
@@ -140,8 +142,22 @@ cifs_open(struct inode *inode, struct file *file)
 			write_lock(&GlobalSMBSeslock);
 			list_add(&pCifsFile->tlist,&pTcon->openFileList);
 			pCifsInode = CIFS_I(file->f_dentry->d_inode);
-			if(pCifsInode->openFileList.next)
+			if(pCifsInode) {
+		                if (pTcon->ses->capabilities & CAP_UNIX)
+					rc = cifs_get_inode_info_unix(&file->f_dentry->d_inode,
+						full_path, inode->i_sb);
+				else
+					rc = cifs_get_inode_info(&file->f_dentry->d_inode,
+						full_path, buf, inode->i_sb);
+
 				list_add(&pCifsFile->flist,&pCifsInode->openFileList);
+				if(oplock == OPLOCK_EXCLUSIVE) {
+					pCifsInode->clientCanCacheAll = TRUE;
+					pCifsInode->clientCanCacheRead = TRUE;
+					cFYI(1,("Exclusive Oplock granted on inode %p",file->f_dentry->d_inode));
+				} else if(oplock == OPLOCK_READ)
+					pCifsInode->clientCanCacheRead = TRUE;
+			}
 			write_unlock(&GlobalSMBSeslock);
 			write_unlock(&file->f_owner.lock);
 			if(file->f_flags & O_CREAT) {           
@@ -162,6 +178,8 @@ cifs_open(struct inode *inode, struct file *file)
 		}
 	}
 
+	if (buf)
+		kfree(buf);
 	if (full_path)
 		kfree(full_path);
 	FreeXid(xid);
@@ -245,6 +263,13 @@ cifs_close(struct inode *inode, struct file *file)
 	} else
 		rc = -EBADF;
 
+	if(list_empty(&(CIFS_I(inode)->openFileList))) {
+		cFYI(1,("closing last open instance for inode %p",inode));
+		/* if the file is not open we do not know if we can cache
+		info on this inode, much less write behind and read ahead */
+		CIFS_I(inode)->clientCanCacheRead = FALSE;
+		CIFS_I(inode)->clientCanCacheAll  = FALSE;
+	}
 	if((rc ==0) && CIFS_I(inode)->write_behind_rc)
 		rc = CIFS_I(inode)->write_behind_rc;
 	FreeXid(xid);
@@ -837,7 +862,13 @@ cifs_readpages(struct file *file, struct address_space *mapping,
 				break;
 			}
 		} else {
-			cFYI(1,("No bytes read"));
+			cFYI(1,("No bytes read cleaning remaining pages off readahead list"));
+			/* BB turn off caching and do new lookup on file size at server? */
+			while (!list_empty(page_list) && (i < num_pages)) {
+				page = list_entry(page_list->prev, struct page, list);
+				list_del(&page->list);
+			}
+
 			break;
 		}
 		if(smb_read_data) {

fs/cifs/inode.c

@@ -43,6 +43,9 @@ cifs_get_inode_info_unix(struct inode **pinode,
 	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
 	char *tmp_path;
 
+/* BB add caching check so we do not go to server to overwrite inode info to cached file
+	where the local file sizes are correct and the server info is stale  BB */
+
 	xid = GetXid();
 
 	pTcon = cifs_sb->tcon;
@@ -169,7 +172,15 @@ cifs_get_inode_info(struct inode **pinode, const unsigned char *search_path,
 	xid = GetXid();
 
 	pTcon = cifs_sb->tcon;
-	cFYI(1, (" Getting info on %s ", search_path));
+	cFYI(1,("Getting info on %s ", search_path));
+
+	if((pfindData == NULL) && (*pinode != NULL)) {
+		if(CIFS_I(*pinode)->clientCanCacheRead) {
+			cFYI(1,("No need to revalidate inode sizes on cached file "));
+			FreeXid(xid);
+			return rc;
+		}
+	}
 
 	/* if file info not passed in then get it from server */
 	if(pfindData == NULL) {

fs/cifs/ntlmssp.h

@@ -27,26 +27,31 @@
 #define NtLmChallenge     2
 #define NtLmAuthenticate  3
 #define UnknownMessage    8
+
 /* Negotiate Flags */
 #define NTLMSSP_NEGOTIATE_UNICODE       0x01	// Text strings are in unicode
 #define NTLMSSP_NEGOTIATE_OEM           0x02	// Text strings are in OEM
 #define NTLMSSP_REQUEST_TARGET          0x04	// Server return its auth realm
 #define NTLMSSP_NEGOTIATE_SIGN        0x0010	// Request signature capability
 #define NTLMSSP_NEGOTIATE_SEAL        0x0020	// Request confidentiality
-#define NTLMSSP_NEGOTIATE_DGRAM       0x0040
+#define NTLMSSP_NEGOTIATE_DGRAM       0x0040
 #define NTLMSSP_NEGOTIATE_LM_KEY      0x0080	// Use LM session key for sign/seal
 #define NTLMSSP_NEGOTIATE_NTLM        0x0200	// NTLM authentication
 #define NTLMSSP_NEGOTIATE_DOMAIN_SUPPLIED 0x1000
 #define NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED 0x2000
 #define NTLMSSP_NEGOTIATE_LOCAL_CALL  0x4000	// client/server on same machine
 #define NTLMSSP_NEGOTIATE_ALWAYS_SIGN 0x8000	// Sign for all security levels
+#define NTLMSSP_TARGET_TYPE_DOMAIN   0x10000
+#define NTLMSSP_TARGET_TYPE_SERVER   0x20000
+#define NTLMSSP_TARGET_TYPE_SHARE    0x40000
 #define NTLMSSP_NEGOTIATE_NTLMV2     0x80000
+#define NTLMSSP_REQUEST_INIT_RESP   0x100000
+#define NTLMSSP_REQUEST_ACCEPT_RESP 0x200000
+#define NTLMSSP_REQUEST_NOT_NT_KEY  0x400000
 #define NTLMSSP_NEGOTIATE_TARGET_INFO 0x800000
 #define NTLMSSP_NEGOTIATE_128     0x20000000
 #define NTLMSSP_NEGOTIATE_KEY_XCH 0x40000000
-/* server only negotiate flags */
-#define NTLMSSP_TARGET_TYPE_DOMAIN  0x10000	/* NEGOTIATE_DOMAIN 0x1000 ? */
-#define NTLMSSP_TARGET_TYPE_SERVER  0x20000	/* NEGOTIATE_WORKSTATION 0x2000 ? */
+#define NTLMSSP_NEGOTIATE_56      0x80000000
 
 /* Although typedefs are not commonly used for structure definitions */
 /* in the Linux kernel, in this particular case they are useful      */
@@ -62,7 +67,7 @@ typedef struct _SECURITY_BUFFER {
 
 typedef struct _NEGOTIATE_MESSAGE {
 	__u8 Signature[sizeof (NTLMSSP_SIGNATURE)];
-	__u32 MessageType;
+	__u32 MessageType;     /* 1 */
 	__u32 NegotiateFlags;
 	SECURITY_BUFFER DomainName;	/* RFC 1001 style and ASCII */
 	SECURITY_BUFFER WorkstationName;	/* RFC 1001 and ASCII */
@@ -72,7 +77,7 @@ typedef struct _NEGOTIATE_MESSAGE {
 
 typedef struct _CHALLENGE_MESSAGE {
 	__u8 Signature[sizeof (NTLMSSP_SIGNATURE)];
-	__u32 MessageType;
+	__u32 MessageType;   /* 2 */
 	SECURITY_BUFFER TargetName;
 	__u32 NegotiateFlags;
 	__u8 Challenge[CIFS_CRYPTO_KEY_SIZE];
@@ -82,7 +87,7 @@ typedef struct _CHALLENGE_MESSAGE {
 
 typedef struct _AUTHENTICATE_MESSAGE {
 	__u8 Signature[sizeof (NTLMSSP_SIGNATURE)];
-	__u32 MessageType;
+	__u32 MessageType;  /* 3 */
 	SECURITY_BUFFER LmChallengeResponse;
 	SECURITY_BUFFER NtChallengeResponse;
 	SECURITY_BUFFER DomainName;