cifs: push rfc1002 generation down the stack

Move the generation of the 4 byte length field down the stack and
generate it immediately before we start writing the data to the socket.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>

1 files changed, 32 insertions, 50 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 1f1a68f..63f25f9 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -241,13 +241,14 @@ __smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
 	int rc;
 	struct kvec *iov = rqst->rq_iov;
 	int n_vec = rqst->rq_nvec;
-	unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);
-	unsigned long send_length;
+	unsigned int send_length;
 	unsigned int i;
 	size_t total_len = 0, sent, size;
 	struct socket *ssocket = server->ssocket;
 	struct msghdr smb_msg;
 	int val = 1;
+	__be32 rfc1002_marker;
+
 	if (cifs_rdma_enabled(server) && server->smbd_conn) {
 		rc = smbd_send(server->smbd_conn, rqst);
 		goto smbd_done;
@@ -255,26 +256,34 @@ __smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
 	if (ssocket == NULL)
 		return -ENOTSOCK;
 
-	/* sanity check send length */
 	send_length = rqst_len(rqst);
-	if (send_length != smb_buf_length + 4) {
-		WARN(1, "Send length mismatch(send_length=%lu smb_buf_length=%u)\n",
-			send_length, smb_buf_length);
-		return -EIO;
-	}
-
-	if (n_vec < 2)
-		return -EIO;
-
-	cifs_dbg(FYI, "Sending smb: smb_len=%u\n", smb_buf_length);
-	dump_smb(iov[0].iov_base, iov[0].iov_len);
-	dump_smb(iov[1].iov_base, iov[1].iov_len);
+	rfc1002_marker = cpu_to_be32(send_length);
 
 	/* cork the socket */
 	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
 				(char *)&val, sizeof(val));
 
 	size = 0;
+	/* Generate a rfc1002 marker for SMB2+ */
+	if (server->vals->header_preamble_size == 0) {
+		struct kvec hiov = {
+			.iov_base = &rfc1002_marker,
+			.iov_len  = 4
+		};
+		iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC, &hiov,
+			      1, 4);
+		rc = smb_send_kvec(server, &smb_msg, &sent);
+		if (rc < 0)
+			goto uncork;
+
+		total_len += sent;
+		send_length += 4;
+	}
+
+	cifs_dbg(FYI, "Sending smb: smb_len=%u\n", send_length);
+	dump_smb(iov[0].iov_base, iov[0].iov_len);
+	dump_smb(iov[1].iov_base, iov[1].iov_len);
+
 	for (i = 0; i < n_vec; i++)
 		size += iov[i].iov_len;
 
@@ -308,9 +317,9 @@ uncork:
 	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
 				(char *)&val, sizeof(val));
 
-	if ((total_len > 0) && (total_len != smb_buf_length + 4)) {
+	if ((total_len > 0) && (total_len != send_length)) {
 		cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
-			 smb_buf_length + 4, total_len);
+			 send_length, total_len);
 		/*
 		 * If we have only sent part of an SMB then the next SMB could
 		 * be taken as the remainder of this one. We need to kill the
@@ -730,7 +739,6 @@ cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	 * to the same server. We may make this configurable later or
 	 * use ses->maxReq.
 	 */
-
 	rc = wait_for_free_request(ses->server, timeout, optype);
 	if (rc)
 		return rc;
@@ -766,8 +774,8 @@ cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 
 #ifdef CONFIG_CIFS_SMB311
 	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP))
-		smb311_update_preauth_hash(ses, rqst->rq_iov+1,
-					   rqst->rq_nvec-1);
+		smb311_update_preauth_hash(ses, rqst->rq_iov,
+					   rqst->rq_nvec);
 #endif
 
 	if (timeout == CIFS_ASYNC_OP)
@@ -812,8 +820,8 @@ cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
 #ifdef CONFIG_CIFS_SMB311
 	if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {
 		struct kvec iov = {
-			.iov_base = buf,
-			.iov_len = midQ->resp_buf_size
+			.iov_base = resp_iov->iov_base,
+			.iov_len = resp_iov->iov_len
 		};
 		smb311_update_preauth_hash(ses, &iov, 1);
 	}
@@ -879,39 +887,13 @@ smb2_send_recv(const unsigned int xid, struct cifs_ses *ses,
 	       const int flags, struct kvec *resp_iov)
 {
 	struct smb_rqst rqst;
-	struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
 	int rc;
-	int i;
-	__u32 count;
-	__be32 rfc1002_marker;
-
-	if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
-		new_iov = kmalloc_array(n_vec + 1, sizeof(struct kvec),
-					GFP_KERNEL);
-		if (!new_iov)
-			return -ENOMEM;
-	} else
-		new_iov = s_iov;
-
-	/* 1st iov is an RFC1002 Session Message length */
-	memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
-
-	count = 0;
-	for (i = 1; i < n_vec + 1; i++)
-		count += new_iov[i].iov_len;
-
-	rfc1002_marker = cpu_to_be32(count);
-
-	new_iov[0].iov_base = &rfc1002_marker;
-	new_iov[0].iov_len = 4;
 
 	memset(&rqst, 0, sizeof(struct smb_rqst));
-	rqst.rq_iov = new_iov;
-	rqst.rq_nvec = n_vec + 1;
+	rqst.rq_iov = iov;
+	rqst.rq_nvec = n_vec;
 
 	rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
-	if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
-		kfree(new_iov);
 	return rc;
 }