Commit 6f49f46b authored by Jeff Layton's avatar Jeff Layton Committed by Steve French
Browse files

cifs: convert send code to use smb_rqst structs 



Again, just a change in the arguments and some function renaming here.
In later patches, we'll change this code to deal with page arrays.

In this patch, we add a new smb_send_rqst wrapper and have smb_sendv
call that. Then we move most of the existing smb_sendv code into a new
function -- smb_send_kvec. This seems a little redundant, but later
we'll flesh this out to deal with arrays of pages.

Reviewed-by: default avatarPavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: default avatarJeff Layton <jlayton@redhat.com>
Signed-off-by: default avatarSteve French <smfrench@gmail.com>
parent 0b688cfc

fs/cifs/transport.c

+90 −45
Original line number Diff line number Diff line
@@ -119,18 +119,29 @@ cifs_delete_mid(struct mid_q_entry *mid) 
	DeleteMidQEntry(mid);

}



/*

 * smb_send_kvec - send an array of kvecs to the server

 * @server:	Server to send the data to

 * @iov:	Pointer to array of kvecs

 * @n_vec:	length of kvec array

 * @sent:	amount of data sent on socket is stored here

 *

 * Our basic "send data to server" function. Should be called with srv_mutex

 * held. The caller is responsible for handling the results.

 */

static int

smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)

smb_send_kvec(struct TCP_Server_Info *server, struct kvec *iov, size_t n_vec,

		size_t *sent)

{

	int rc = 0;

	int i = 0;

	struct msghdr smb_msg;

	unsigned int len = iov[0].iov_len;

	unsigned int total_len;

	int first_vec = 0;

	unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);

	unsigned int remaining;

	size_t first_vec = 0;

	struct socket *ssocket = server->ssocket;



	*sent = 0;



	if (ssocket == NULL)

		return -ENOTSOCK; /* BB eventually add reconnect code here */
@@ -143,21 +154,14 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) 
	else

		smb_msg.msg_flags = MSG_NOSIGNAL;



	total_len = 0;

	remaining = 0;

	for (i = 0; i < n_vec; i++)

		total_len += iov[i].iov_len;



	cFYI(1, "Sending smb:  total_len %d", total_len);

	dump_smb(iov[0].iov_base, len);

		remaining += iov[i].iov_len;



	i = 0;

	while (total_len) {

		rc = kernel_sendmsg(ssocket, &smb_msg, &iov[first_vec],

				    n_vec - first_vec, total_len);

		if ((rc == -ENOSPC) || (rc == -EAGAIN)) {

			i++;

	while (remaining) {

		/*

			 * If blocking send we try 3 times, since each can block

		 * If blocking send, we try 3 times, since each can block

		 * for 5 seconds. For nonblocking  we have to try more

		 * but wait increasing amounts of time allowing time for

		 * socket to clear.  The overall time we wait in either
@@ -174,25 +178,36 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) 
		 * after the retries we will kill the socket and

		 * reconnect which may clear the network problem.

		 */

			if ((i >= 14) || (!server->noblocksnd && (i > 2))) {

				cERROR(1, "sends on sock %p stuck for 15 seconds",

				    ssocket);

		rc = kernel_sendmsg(ssocket, &smb_msg, &iov[first_vec],

				    n_vec - first_vec, remaining);

		if (rc == -ENOSPC || rc == -EAGAIN) {

			i++;

			if (i >= 14 || (!server->noblocksnd && (i > 2))) {

				cERROR(1, "sends on sock %p stuck for 15 "

					  "seconds", ssocket);

				rc = -EAGAIN;

				break;

			}

			msleep(1 << i);

			continue;

		}



		if (rc < 0)

			break;



		if (rc == total_len) {

			total_len = 0;

		/* send was at least partially successful */

		*sent += rc;



		if (rc == remaining) {

			remaining = 0;

			break;

		} else if (rc > total_len) {

			cERROR(1, "sent %d requested %d", rc, total_len);

		}



		if (rc > remaining) {

			cERROR(1, "sent %d requested %d", rc, remaining);

			break;

		}



		if (rc == 0) {

			/* should never happen, letting socket clear before

			   retrying is our only obvious option here */
@@ -200,7 +215,9 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) 
			msleep(500);

			continue;

		}

		total_len -= rc;



		remaining -= rc;



		/* the line below resets i */

		for (i = first_vec; i < n_vec; i++) {

			if (iov[i].iov_len) {
@@ -215,16 +232,35 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) 
				}

			}

		}



		i = 0; /* in case we get ENOSPC on the next send */

		rc = 0;

	}

	return rc;

}



static int

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);

	size_t total_len;



	cFYI(1, "Sending smb: smb_len=%u", smb_buf_length);

	dump_smb(iov[0].iov_base, iov[0].iov_len);



	rc = smb_send_kvec(server, iov, n_vec, &total_len);



	if ((total_len > 0) && (total_len != smb_buf_length + 4)) {

		cFYI(1, "partial send (%d remaining), terminating session",

			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 socket so the server throws away the partial

		   SMB */

		cFYI(1, "partial send (wanted=%u sent=%zu): terminating "

			"session", smb_buf_length + 4, 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

		 * socket so the server throws away the partial SMB

		 */

		server->tcpStatus = CifsNeedReconnect;

	}
@@ -236,6 +272,15 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec) 
	return rc;

}



static int

smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)

{

	struct smb_rqst rqst = { .rq_iov = iov,

				 .rq_nvec = n_vec };



	return smb_send_rqst(server, &rqst);

}



int

smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,

	 unsigned int smb_buf_length)

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