CIFS: Add readpage support for SMB2
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index cb6acc7..23c5693 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1329,6 +1329,57 @@
return rc;
}
+int
+SMB2_read(const unsigned int xid, struct cifs_io_parms *io_parms,
+ unsigned int *nbytes, char **buf, int *buf_type)
+{
+ int resp_buftype, rc = -EACCES;
+ struct smb2_read_rsp *rsp = NULL;
+ struct kvec iov[1];
+
+ *nbytes = 0;
+ rc = smb2_new_read_req(iov, io_parms, 0, 0);
+ if (rc)
+ return rc;
+
+ rc = SendReceive2(xid, io_parms->tcon->ses, iov, 1,
+ &resp_buftype, CIFS_LOG_ERROR);
+
+ rsp = (struct smb2_read_rsp *)iov[0].iov_base;
+
+ if (rsp->hdr.Status == STATUS_END_OF_FILE) {
+ free_rsp_buf(resp_buftype, iov[0].iov_base);
+ return 0;
+ }
+
+ if (rc) {
+ cifs_stats_fail_inc(io_parms->tcon, SMB2_READ_HE);
+ cERROR(1, "Send error in read = %d", rc);
+ } else {
+ *nbytes = le32_to_cpu(rsp->DataLength);
+ if ((*nbytes > CIFS_MAX_MSGSIZE) ||
+ (*nbytes > io_parms->length)) {
+ cFYI(1, "bad length %d for count %d", *nbytes,
+ io_parms->length);
+ rc = -EIO;
+ *nbytes = 0;
+ }
+ }
+
+ if (*buf) {
+ memcpy(*buf, (char *)rsp->hdr.ProtocolId + rsp->DataOffset,
+ *nbytes);
+ free_rsp_buf(resp_buftype, iov[0].iov_base);
+ } else if (resp_buftype != CIFS_NO_BUFFER) {
+ *buf = iov[0].iov_base;
+ if (resp_buftype == CIFS_SMALL_BUFFER)
+ *buf_type = CIFS_SMALL_BUFFER;
+ else if (resp_buftype == CIFS_LARGE_BUFFER)
+ *buf_type = CIFS_LARGE_BUFFER;
+ }
+ return rc;
+}
+
/*
* Check the mid_state and signature on received buffer (if any), and queue the
* workqueue completion task.