[CIFS] Allow SMBWrite2 to work to older servers

Signed-off-by: Steve French (sfrench@us.ibm.com)

1 files changed, 22 insertions, 7 deletions

diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 365949c14646..41996a240149 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -1139,11 +1139,15 @@ CIFSSMBWrite2(const int xid, struct cifsTconInfo *tcon,
 {
         int rc = -EACCES;
         WRITE_REQ *pSMB = NULL;
-        int bytes_returned;
+        int bytes_returned, wct;
         int smb_hdr_len;
 
         cFYI(1,("write2 at %lld %d bytes",offset,count)); /* BB removeme BB */
-        rc = small_smb_init(SMB_COM_WRITE_ANDX, 14, tcon, (void **) &pSMB);
+        if(tcon->ses->capabilities & CAP_LARGE_FILES)
+                wct = 14;
+        else
+                wct = 12;
+        rc = small_smb_init(SMB_COM_WRITE_ANDX, wct, tcon, (void **) &pSMB);
         if (rc)
                 return rc;
         /* tcon and ses pointer are checked in smb_init */
@@ -1153,7 +1157,10 @@ CIFSSMBWrite2(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;
@@ -1164,9 +1171,17 @@ CIFSSMBWrite2(const int xid, struct cifsTconInfo *tcon,
         pSMB->DataLengthLow = cpu_to_le16(count & 0xFFFF);
         pSMB->DataLengthHigh = cpu_to_le16(count >> 16);
         smb_hdr_len = pSMB->hdr.smb_buf_length + 1; /* hdr + 1 byte pad */
-        pSMB->hdr.smb_buf_length += count+1;
-        pSMB->ByteCount = cpu_to_le16(count + 1);
-
+        if(wct == 14)
+                pSMB->hdr.smb_buf_length += count+1;
+        else /* wct == 12 */
+                pSMB->hdr.smb_buf_length += count+5; /* smb data starts later */ 
+        if(wct == 14)
+                pSMB->ByteCount = cpu_to_le16(count + 1);
+        else /* wct == 12 */ /* bigger pad, smaller smb hdr, keep offset ok */ {
+                struct smb_com_writex_req * pSMBW =
+                                (struct smb_com_writex_req *)pSMB;
+                pSMBW->ByteCount = cpu_to_le16(count + 5);
+        }
         iov[0].iov_base = pSMB;
         iov[0].iov_len = smb_hdr_len + 4;
 
@@ -1174,7 +1189,7 @@ CIFSSMBWrite2(const int xid, struct cifsTconInfo *tcon,
                           long_op);
         cifs_stats_inc(&tcon->num_writes);
         if (rc) {
-                cFYI(1, ("Send error in write = %d", rc));
+                cFYI(1, ("Send error Write2 = %d", rc));
                 *nbytes = 0;
         } else {
                 WRITE_RSP * pSMBr = (WRITE_RSP *)pSMB;