[CIFS] Support for legacy servers part 3 - Add support for Open and most

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

fs/cifs/cifspdu.h

@@ -40,6 +40,7 @@
 #define SMB_COM_SETATTR               0x09 /* trivial response */
 #define SMB_COM_LOCKING_ANDX          0x24 /* trivial response */
 #define SMB_COM_COPY                  0x29 /* trivial rsp, fail filename ignrd*/
+#define SMB_COM_OPEN_ANDX             0x2D /* Legacy open for old servers */
 #define SMB_COM_READ_ANDX             0x2E
 #define SMB_COM_WRITE_ANDX            0x2F
 #define SMB_COM_TRANSACTION2          0x32
@@ -625,6 +626,7 @@ typedef struct smb_com_findclose_req {
 } FINDCLOSE_REQ;
 
 /* OpenFlags */
+#define REQ_MORE_INFO      0x00000001  /* legacy (OPEN_AND_X) only */
 #define REQ_OPLOCK         0x00000002
 #define REQ_BATCHOPLOCK    0x00000004
 #define REQ_OPENDIRONLY    0x00000008
@@ -680,6 +682,62 @@ typedef struct smb_com_open_rsp {
 	__u16 ByteCount;	/* bct = 0 */
 } OPEN_RSP;
 
+/* format of legacy open request */
+typedef struct smb_com_openx_req {
+	struct smb_hdr	hdr;	/* wct = 15 */
+	__u8 AndXCommand;
+	__u8 AndXReserved;
+	__le16 AndXOffset;
+	__le16 OpenFlags;
+	__le16 Mode;
+	__le16 Sattr; /* search attributes */
+	__le16 FileAttributes;  /* dos attrs */
+	__le32 CreateTime; /* os2 format */
+	__le16 OpenFunction;
+	__le32 EndOfFile;
+	__le32 Timeout;
+	__le32 Reserved;
+	__u16  ByteCount;  /* file name follows */
+	char   fileName[1];
+} OPENX_REQ;
+
+typedef struct smb_com_openx_rsp {
+	struct smb_hdr	hdr;	/* wct = 15 */
+	__u8 AndXCommand;
+	__u8 AndXReserved;
+	__le16 AndXOffset;
+	__u16  Fid;
+	__le16 FileAttributes;
+	__le32 LastWriteTime; /* os2 format */
+	__le32 EndOfFile;
+	__le16 Access;
+	__le16 FileType;
+	__le16 IPCState;
+	__le16 Action;
+	__u32  FileId;
+	__u16  Reserved;
+	__u16  ByteCount;
+} OPENX_RSP; 
+
+/* Legacy write request for older servers */
+typedef struct smb_com_writex_req {
+        struct smb_hdr hdr;     /* wct = 12 */
+        __u8 AndXCommand;
+        __u8 AndXReserved;
+        __le16 AndXOffset;
+        __u16 Fid;
+        __le32 OffsetLow;
+        __u32 Reserved; /* Timeout */
+        __le16 WriteMode; /* 1 = write through */
+        __le16 Remaining;
+        __le16 Reserved2;
+        __le16 DataLengthLow;
+        __le16 DataOffset;
+        __le16 ByteCount;
+        __u8 Pad;               /* BB check for whether padded to DWORD boundary and optimum performance here */
+        char Data[0];
+} WRITEX_REQ;
+
 typedef struct smb_com_write_req {
 	struct smb_hdr hdr;	/* wct = 14 */
 	__u8 AndXCommand;
@@ -711,6 +769,21 @@ typedef struct smb_com_write_rsp {
 	__u16 ByteCount;
 } WRITE_RSP;
 
+/* legacy read request for older servers */
+typedef struct smb_com_readx_req {
+        struct smb_hdr hdr;     /* wct = 10 */
+        __u8 AndXCommand;
+        __u8 AndXReserved;
+        __le16 AndXOffset;
+        __u16 Fid;
+        __le32 OffsetLow;
+        __le16 MaxCount;
+        __le16 MinCount;                /* obsolete */
+        __le32 Reserved;
+        __le16 Remaining;
+        __le16 ByteCount;
+} READX_REQ;
+
 typedef struct smb_com_read_req {
 	struct smb_hdr hdr;	/* wct = 12 */
 	__u8 AndXCommand;

fs/cifs/cifsproto.h

@@ -218,9 +218,17 @@ extern int CIFSSMBOpen(const int xid, struct cifsTconInfo *tcon,
 			const int access_flags, const int omode,
 			__u16 * netfid, int *pOplock, FILE_ALL_INFO *,
 			const struct nls_table *nls_codepage, int remap);
+extern int SMBLegacyOpen(const int xid, struct cifsTconInfo *tcon,
+			const char *fileName, const int disposition,
+			const int access_flags, const int omode,
+			__u16 * netfid, int *pOplock, FILE_ALL_INFO *,
+			const struct nls_table *nls_codepage, int remap);
 extern int CIFSSMBClose(const int xid, struct cifsTconInfo *tcon,
 			const int smb_file_id);
 
+extern int SMBLegacyRead(const int xid, struct cifsTconInfo *tcon,
+			const int netfid, unsigned int count,
+			const __u64 lseek, unsigned int *nbytes, char **buf);
 extern int CIFSSMBRead(const int xid, struct cifsTconInfo *tcon,
 			const int netfid, unsigned int count,
 			const __u64 lseek, unsigned int *nbytes, char **buf);

fs/cifs/cifssmb.c

@@ -680,6 +680,146 @@ CIFSSMBMkDir(const int xid, struct cifsTconInfo *tcon,
 	return rc;
 }
 
+static __u16 convert_disposition(int disposition)
+{
+	__u16 ofun = 0;
+
+	switch (disposition) {
+		case FILE_SUPERSEDE:
+			ofun = SMBOPEN_OCREATE | SMBOPEN_OTRUNC;
+			break;
+		case FILE_OPEN:
+			ofun = SMBOPEN_OAPPEND;
+			break;
+		case FILE_CREATE:
+			ofun = SMBOPEN_OCREATE;
+			break;
+		case FILE_OPEN_IF:
+			ofun = SMBOPEN_OCREATE | SMBOPEN_OAPPEND;
+			break;
+		case FILE_OVERWRITE:
+			ofun = SMBOPEN_OTRUNC;
+			break;
+		case FILE_OVERWRITE_IF:
+			ofun = SMBOPEN_OCREATE | SMBOPEN_OTRUNC;
+			break;
+		default:
+			cFYI(1,("unknown disposition %d",disposition));
+			ofun =  SMBOPEN_OAPPEND; /* regular open */
+	}
+	return ofun;
+}
+
+int
+SMBLegacyOpen(const int xid, struct cifsTconInfo *tcon,
+	    const char *fileName, const int openDisposition,
+	    const int access_flags, const int create_options, __u16 * netfid,
+            int *pOplock, FILE_ALL_INFO * pfile_info,
+	    const struct nls_table *nls_codepage, int remap)
+{
+	int rc = -EACCES;
+	OPENX_REQ *pSMB = NULL;
+	OPENX_RSP *pSMBr = NULL;
+	int bytes_returned;
+	int name_len;
+	__u16 count;
+
+OldOpenRetry:
+	rc = smb_init(SMB_COM_OPEN_ANDX, 15, tcon, (void **) &pSMB,
+		      (void **) &pSMBr);
+	if (rc)
+		return rc;
+
+	pSMB->AndXCommand = 0xFF;       /* none */
+
+	if (pSMB->hdr.Flags2 & SMBFLG2_UNICODE) {
+		count = 1;      /* account for one byte pad to word boundary */
+		name_len =
+		   cifsConvertToUCS((__le16 *) (pSMB->fileName + 1),
+				    fileName, PATH_MAX, nls_codepage, remap);
+		name_len++;     /* trailing null */
+		name_len *= 2;
+	} else {                /* BB improve check for buffer overruns BB */
+		count = 0;      /* no pad */
+		name_len = strnlen(fileName, PATH_MAX);
+		name_len++;     /* trailing null */
+		strncpy(pSMB->fileName, fileName, name_len);
+	}
+	if (*pOplock & REQ_OPLOCK)
+		pSMB->OpenFlags = cpu_to_le16(REQ_OPLOCK);
+	else if (*pOplock & REQ_BATCHOPLOCK) {
+		pSMB->OpenFlags = cpu_to_le16(REQ_BATCHOPLOCK);
+	}
+	pSMB->OpenFlags |= cpu_to_le16(REQ_MORE_INFO);
+	/* BB fixme add conversion for access_flags to bits 0 - 2 of mode */
+	/* 0 = read
+	   1 = write
+	   2 = rw
+	   3 = execute
+        */
+	pSMB->Mode = cpu_to_le16(2);
+	pSMB->Mode |= cpu_to_le16(0x40); /* deny none */
+	/* set file as system file if special file such
+	   as fifo and server expecting SFU style and
+	   no Unix extensions */
+
+        if(create_options & CREATE_OPTION_SPECIAL)
+                pSMB->FileAttributes = cpu_to_le16(ATTR_SYSTEM);
+        else
+                pSMB->FileAttributes = cpu_to_le16(ATTR_NORMAL);
+
+	/* if ((omode & S_IWUGO) == 0)
+		pSMB->FileAttributes |= cpu_to_le32(ATTR_READONLY);*/
+	/*  Above line causes problems due to vfs splitting create into two
+	    pieces - need to set mode after file created not while it is
+	    being created */
+
+	/* BB FIXME BB */
+/*	pSMB->CreateOptions = cpu_to_le32(create_options & CREATE_OPTIONS_MASK); */
+	/* BB FIXME END BB */
+	pSMB->OpenFunction = convert_disposition(openDisposition);
+	count += name_len;
+	pSMB->hdr.smb_buf_length += count;
+
+	pSMB->ByteCount = cpu_to_le16(count);
+	/* long_op set to 1 to allow for oplock break timeouts */
+	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+		         (struct smb_hdr *) pSMBr, &bytes_returned, 1);
+	cifs_stats_inc(&tcon->num_opens);
+	if (rc) {
+		cFYI(1, ("Error in Open = %d", rc));
+	} else {
+	/* BB verify if wct == 15 */
+
+/*		*pOplock = pSMBr->OplockLevel; */  /* BB take from action field BB */
+
+		*netfid = pSMBr->Fid;   /* cifs fid stays in le */
+		/* Let caller know file was created so we can set the mode. */
+		/* Do we care about the CreateAction in any other cases? */
+	/* BB FIXME BB */
+/*		if(cpu_to_le32(FILE_CREATE) == pSMBr->CreateAction)
+			*pOplock |= CIFS_CREATE_ACTION; */
+	/* BB FIXME END */
+
+		if(pfile_info) {
+			pfile_info->CreationTime = 0; /* BB convert CreateTime*/
+			pfile_info->LastAccessTime = 0; /* BB fixme */
+			pfile_info->LastWriteTime = 0; /* BB fixme */
+			pfile_info->ChangeTime = 0;  /* BB fixme */
+			pfile_info->Attributes = pSMBr->FileAttributes; 
+			/* the file_info buf is endian converted by caller */
+			pfile_info->AllocationSize = pSMBr->EndOfFile;
+			pfile_info->EndOfFile = pSMBr->EndOfFile;
+			pfile_info->NumberOfLinks = cpu_to_le32(1);
+		}
+	}
+
+	cifs_buf_release(pSMB);
+	if (rc == -EAGAIN)
+		goto OldOpenRetry;
+	return rc;
+}
+
 int
 CIFSSMBOpen(const int xid, struct cifsTconInfo *tcon,
 	    const char *fileName, const int openDisposition,
@@ -783,6 +923,81 @@ CIFSSMBOpen(const int xid, struct cifsTconInfo *tcon,
 	return rc;
 }
 
+int
+SMBLegacyRead(const int xid, struct cifsTconInfo *tcon,
+            const int netfid, unsigned int count,
+            const __u64 lseek, unsigned int *nbytes, char **buf)
+{
+	int rc = -EACCES;
+	READX_REQ *pSMB = NULL;
+	READ_RSP *pSMBr = NULL;
+	char *pReadData = NULL;
+	int bytes_returned;
+
+	cFYI(1,("Legacy read %d bytes fid %d",count,netfid));
+
+	/* field is shorter in legacy read, only 16 bits */
+	if(count > 2048)
+		count = 2048;  /* BB FIXME make this configurable */
+
+	if(lseek > 0xFFFFFFFF)
+		return -EIO; /* can not read that far into file on old server */
+
+	*nbytes = 0;
+	rc = smb_init(SMB_COM_READ_ANDX, 10, tcon, (void **) &pSMB,
+		      (void **) &pSMBr);
+	if (rc)
+		return rc;
+
+	/* tcon and ses pointer are checked in smb_init */
+	if (tcon->ses->server == NULL)
+		return -ECONNABORTED;
+
+	pSMB->AndXCommand = 0xFF;       /* none */
+	pSMB->Fid = netfid;
+	pSMB->OffsetLow = cpu_to_le32(lseek & 0xFFFFFFFF);
+	pSMB->Remaining = 0;
+	pSMB->MaxCount = cpu_to_le16(count);
+	pSMB->Reserved = 0; /* Must Be Zero */
+	pSMB->ByteCount = 0;  /* no need to do le conversion since it is 0 */
+
+	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+			 (struct smb_hdr *) pSMBr, &bytes_returned, 0);
+	cifs_stats_inc(&tcon->num_reads);
+	if (rc) {
+		cERROR(1, ("Send error in legacy read = %d", rc));
+	} else {
+		int data_length = le16_to_cpu(pSMBr->DataLengthHigh);
+		data_length = data_length << 16;
+		data_length += le16_to_cpu(pSMBr->DataLength);
+		*nbytes = data_length;
+
+		/*check that DataLength would not go beyond end of SMB */
+		if ((data_length > CIFSMaxBufSize) || (data_length > count)) {
+			cFYI(1,("bad length %d for count %d",data_length,count));
+			rc = -EIO;
+			*nbytes = 0;
+		} else {
+			pReadData = (char *) (&pSMBr->hdr.Protocol) +
+						le16_to_cpu(pSMBr->DataOffset);
+/*                      if(rc = copy_to_user(buf, pReadData, data_length)) {
+			 	cERROR(1,("Faulting on read rc = %d",rc));
+				rc = -EFAULT;
+			}*/ /* can not use copy_to_user when using page cache*/
+			if(*buf)
+				memcpy(*buf,pReadData,data_length);
+		}
+	}
+	if(*buf)
+		cifs_buf_release(pSMB);
+	else
+		*buf = (char *)pSMB;
+
+	/* Note: On -EAGAIN error only caller can retry on handle based calls
+		since file handle passed in no longer valid */
+	return rc;
+}
+
 /* If no buffer passed in, then caller wants to do the copy
 	as in the case of readpages so the SMB buffer must be
 	freed by the caller */

fs/cifs/dir.c

@@ -184,6 +184,13 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 			 desiredAccess, CREATE_NOT_DIR,
 			 &fileHandle, &oplock, buf, cifs_sb->local_nls,
 			 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+	if(rc == -EIO) {
+		/* old server, retry the open legacy style */
+		rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
+			desiredAccess, CREATE_NOT_DIR,
+			&fileHandle, &oplock, buf, cifs_sb->local_nls,
+			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+	} 
 	if (rc) {
 		cFYI(1, ("cifs_create returned 0x%x ", rc));
 	} else {

fs/cifs/file.c

@@ -256,6 +256,13 @@ int cifs_open(struct inode *inode, struct file *file)
 			 CREATE_NOT_DIR, &netfid, &oplock, buf,
 			 cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
 				 & CIFS_MOUNT_MAP_SPECIAL_CHR);
+	if (rc == -EIO) {
+		/* Old server, try legacy style OpenX */
+		rc = SMBLegacyOpen(xid, pTcon, full_path, disposition,
+			desiredAccess, CREATE_NOT_DIR, &netfid, &oplock, buf,
+			cifs_sb->local_nls, cifs_sb->mnt_cifs_flags
+				& CIFS_MOUNT_MAP_SPECIAL_CHR);
+	}
 	if (rc) {
 		cFYI(1, ("cifs_open returned 0x%x ", rc));
 		goto out;
@@ -1210,7 +1217,12 @@ ssize_t cifs_user_read(struct file *file, char __user *read_data,
 				 open_file->netfid,
 				 current_read_size, *poffset,
 				 &bytes_read, &smb_read_data);
-
+			if(rc == -EINVAL) {
+				rc = SMBLegacyRead(xid, pTcon,
+					open_file->netfid,
+					current_read_size, *poffset,
+					&bytes_read, &smb_read_data);
+			}
 			pSMBr = (struct smb_com_read_rsp *)smb_read_data;
 			if (copy_to_user(current_offset, 
 					 smb_read_data + 4 /* RFC1001 hdr */
@@ -1287,6 +1299,12 @@ static ssize_t cifs_read(struct file *file, char *read_data, size_t read_size,
 				 open_file->netfid,
 				 current_read_size, *poffset,
 				 &bytes_read, &current_offset);
+			if(rc == -EINVAL) {
+				rc = SMBLegacyRead(xid, pTcon,
+					open_file->netfid,
+					current_read_size, *poffset,
+					&bytes_read, &current_offset);
+			}
 		}
 		if (rc || (bytes_read == 0)) {
 			if (total_read) {
@@ -1443,7 +1461,14 @@ static int cifs_readpages(struct file *file, struct address_space *mapping,
 				open_file->netfid,
 				read_size, offset,
 				&bytes_read, &smb_read_data);
-			/* BB need to check return code here */
+			if (rc == -EINVAL) {
+				rc = SMBLegacyRead(xid, pTcon,
+					open_file->netfid,
+					read_size, offset,
+					&bytes_read, &smb_read_data);
+			}
+
+			/* BB more RC checks ? */
 			if (rc== -EAGAIN) {
 				if (smb_read_data) {
 					cifs_buf_release(smb_read_data);