[CIFS] Add support for legacy servers part 4

	Fix WriteX support for old servers which do not support large
	files.

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

fs/cifs/cifssmb.c

@@ -1082,12 +1082,20 @@ CIFSSMBWrite(const int xid, struct cifsTconInfo *tcon,
 	int rc = -EACCES;
 	WRITE_REQ *pSMB = NULL;
 	WRITE_RSP *pSMBr = NULL;
-	int bytes_returned;
+	int bytes_returned, wct;
 	__u32 bytes_sent;
 	__u16 byte_count;
 
 	/* cFYI(1,("write at %lld %d bytes",offset,count));*/
-	rc = smb_init(SMB_COM_WRITE_ANDX, 14, tcon, (void **) &pSMB,
+	if(tcon->ses == NULL)
+		return -ECONNABORTED;
+
+	if(tcon->ses->capabilities & CAP_LARGE_FILES)
+		wct = 14;
+	else
+		wct = 12;
+
+	rc = smb_init(SMB_COM_WRITE_ANDX, wct, tcon, (void **) &pSMB,
 		      (void **) &pSMBr);
 	if (rc)
 		return rc;
@@ -1098,7 +1106,11 @@ CIFSSMBWrite(const int xid, struct cifsTconInfo *tcon,
 	pSMB->AndXCommand = 0xFF;	/* none */
 	pSMB->Fid = netfid;
 	pSMB->OffsetLow = cpu_to_le32(offset & 0xFFFFFFFF);
-	pSMB->OffsetHigh = cpu_to_le32(offset >> 32);
+	if(wct == 14) 
+		pSMB->OffsetHigh = cpu_to_le32(offset >> 32);
+	else if((offset >> 32) > 0) /* can not handle this big offset for old */
+		return -EIO;
+	
 	pSMB->Reserved = 0xFFFFFFFF;
 	pSMB->WriteMode = 0;
 	pSMB->Remaining = 0;
@@ -1135,7 +1147,14 @@ CIFSSMBWrite(const int xid, struct cifsTconInfo *tcon,
 	pSMB->DataLengthLow = cpu_to_le16(bytes_sent & 0xFFFF);
 	pSMB->DataLengthHigh = cpu_to_le16(bytes_sent >> 16);
 	pSMB->hdr.smb_buf_length += bytes_sent+1;
-	pSMB->ByteCount = cpu_to_le16(byte_count);
+
+	if(wct == 14)
+		pSMB->ByteCount = cpu_to_le16(byte_count);
+	else { /* old style write has byte count 4 bytes earlier */
+		struct smb_com_writex_req * pSMBW = 
+			(struct smb_com_writex_req *)pSMB;
+		pSMBW->ByteCount = cpu_to_le16(byte_count);
+	}
 
 	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
 			 (struct smb_hdr *) pSMBr, &bytes_returned, long_op);

fs/cifs/connect.c

@@ -1079,7 +1079,7 @@ cifs_parse_mount_options(char *options, const char *devname,struct smb_vol *vol)
 		} else if (strnicmp(data, "brl", 3) == 0) {
 			vol->nobrl =  0;
 		} else if ((strnicmp(data, "nobrl", 5) == 0) || 
-			   (strnicmp(data, "nolock", 6)) {
+			   (strnicmp(data, "nolock", 6) == 0)) {
 			vol->nobrl =  1;
 			/* turn off mandatory locking in mode
 			if remote locking is turned off since the

fs/cifs/file.c

@@ -1183,11 +1183,16 @@ ssize_t cifs_user_read(struct file *file, char __user *read_data,
 	char *smb_read_data;
 	char __user *current_offset;
 	struct smb_com_read_rsp *pSMBr;
+	int use_old_read = FALSE;
 
 	xid = GetXid();
 	cifs_sb = CIFS_SB(file->f_dentry->d_sb);
 	pTcon = cifs_sb->tcon;
 
+	if(pTcon->ses)
+		if((pTcon->ses->capabilities & CAP_LARGE_FILES) == 0)
+			use_old_read = TRUE;
+
 	if (file->private_data == NULL) {
 		FreeXid(xid);
 		return -EBADF;
@@ -1212,16 +1217,21 @@ ssize_t cifs_user_read(struct file *file, char __user *read_data,
 				if (rc != 0)
 					break;
 			}
-
-			rc = CIFSSMBRead(xid, pTcon,
-				 open_file->netfid,
-				 current_read_size, *poffset,
-				 &bytes_read, &smb_read_data);
-			if(rc == -EINVAL) {
+			if(use_old_read)
 				rc = SMBLegacyRead(xid, pTcon,
 					open_file->netfid,
 					current_read_size, *poffset,
 					&bytes_read, &smb_read_data);
+			else {
+				rc = CIFSSMBRead(xid, pTcon,
+					open_file->netfid,
+					current_read_size, *poffset,
+					&bytes_read, &smb_read_data);
+				if(rc == -EINVAL) {
+					use_old_read = TRUE;
+					rc = -EAGAIN;
+					continue;
+				}
 			}
 			pSMBr = (struct smb_com_read_rsp *)smb_read_data;
 			if (copy_to_user(current_offset, 
@@ -1266,6 +1276,7 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
 	int xid;
 	char *current_offset;
 	struct cifsFileInfo *open_file;
+	int use_old_read = FALSE;
 
 	xid = GetXid();
 	cifs_sb = CIFS_SB(file->f_dentry->d_sb);
@@ -1276,6 +1287,9 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
 		return -EBADF;
 	}
 	open_file = (struct cifsFileInfo *)file->private_data;
+	if(pTcon->ses)
+		if((pTcon->ses->capabilities & CAP_LARGE_FILES) == 0)
+			use_old_read = TRUE;
 
 	if ((file->f_flags & O_ACCMODE) == O_WRONLY)
 		cFYI(1, ("attempting read on write only file instance"));
@@ -1294,16 +1308,23 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
 				if (rc != 0)
 					break;
 			}
-
-			rc = CIFSSMBRead(xid, pTcon,
-				 open_file->netfid,
-				 current_read_size, *poffset,
-				 &bytes_read, &current_offset);
-			if(rc == -EINVAL) {
+			if(use_old_read) 
 				rc = SMBLegacyRead(xid, pTcon,
+					 open_file->netfid,
+					 current_read_size, *poffset,
+					 &bytes_read, &current_offset);
+			else {
+				rc = CIFSSMBRead(xid, pTcon,
 					open_file->netfid,
 					current_read_size, *poffset,
 					&bytes_read, &current_offset);
+				/* check if server disavows support for
+				   64 bit offsets */
+				if(rc == -EINVAL) {
+					rc = -EAGAIN;
+					use_old_read = TRUE;
+					continue;
+				}
 			}
 		}
 		if (rc || (bytes_read == 0)) {
@@ -1402,6 +1423,7 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 	struct smb_com_read_rsp *pSMBr;
 	struct pagevec lru_pvec;
 	struct cifsFileInfo *open_file;
+	int use_old_read = FALSE;
 
 	xid = GetXid();
 	if (file->private_data == NULL) {
@@ -1411,7 +1433,9 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 	open_file = (struct cifsFileInfo *)file->private_data;
 	cifs_sb = CIFS_SB(file->f_dentry->d_sb);
 	pTcon = cifs_sb->tcon;
-
+	if(pTcon->ses)
+		if((pTcon->ses->capabilities & CAP_LARGE_FILES) == 0)
+			use_old_read = TRUE;
 	pagevec_init(&lru_pvec, 0);
 
 	for (i = 0; i < num_pages; ) {
@@ -1457,15 +1481,21 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 					break;
 			}
 
-			rc = CIFSSMBRead(xid, pTcon,
-				open_file->netfid,
-				read_size, offset,
-				&bytes_read, &smb_read_data);
-			if (rc == -EINVAL) {
+			if(use_old_read)
 				rc = SMBLegacyRead(xid, pTcon,
 					open_file->netfid,
 					read_size, offset,
 					&bytes_read, &smb_read_data);
+			else {
+				rc = CIFSSMBRead(xid, pTcon,
+					open_file->netfid,
+					read_size, offset,
+					&bytes_read, &smb_read_data);
+				if(rc == -EINVAL) {
+					use_old_read = TRUE;
+					rc = -EAGAIN;
+					continue;
+				}
 			}
 
 			/* BB more RC checks ? */