コード例 #1
0
ファイル: transport.c プロジェクト: avagin/linux
static int
__smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
		struct smb_rqst *rqst)
{
	int rc = 0;
	struct kvec *iov;
	int n_vec;
	unsigned int send_length = 0;
	unsigned int i, j;
	sigset_t mask, oldmask;
	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, num_rqst, rqst);
		goto smbd_done;
	}

	if (ssocket == NULL)
		return -EAGAIN;

	if (signal_pending(current)) {
		cifs_dbg(FYI, "signal is pending before sending any data\n");
		return -EINTR;
	}

	/* cork the socket */
	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
				(char *)&val, sizeof(val));

	for (j = 0; j < num_rqst; j++)
		send_length += smb_rqst_len(server, &rqst[j]);
	rfc1002_marker = cpu_to_be32(send_length);

	/*
	 * We should not allow signals to interrupt the network send because
	 * any partial send will cause session reconnects thus increasing
	 * latency of system calls and overload a server with unnecessary
	 * requests.
	 */

	sigfillset(&mask);
	sigprocmask(SIG_BLOCK, &mask, &oldmask);

	/* 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, &hiov, 1, 4);
		rc = smb_send_kvec(server, &smb_msg, &sent);
		if (rc < 0)
			goto unmask;

		total_len += sent;
		send_length += 4;
	}

	cifs_dbg(FYI, "Sending smb: smb_len=%u\n", send_length);

	for (j = 0; j < num_rqst; j++) {
		iov = rqst[j].rq_iov;
		n_vec = rqst[j].rq_nvec;

		size = 0;
		for (i = 0; i < n_vec; i++) {
			dump_smb(iov[i].iov_base, iov[i].iov_len);
			size += iov[i].iov_len;
		}

		iov_iter_kvec(&smb_msg.msg_iter, WRITE, iov, n_vec, size);

		rc = smb_send_kvec(server, &smb_msg, &sent);
		if (rc < 0)
			goto unmask;

		total_len += sent;

		/* now walk the page array and send each page in it */
		for (i = 0; i < rqst[j].rq_npages; i++) {
			struct bio_vec bvec;

			bvec.bv_page = rqst[j].rq_pages[i];
			rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
					     &bvec.bv_offset);

			iov_iter_bvec(&smb_msg.msg_iter, WRITE,
				      &bvec, 1, bvec.bv_len);
			rc = smb_send_kvec(server, &smb_msg, &sent);
			if (rc < 0)
				break;

			total_len += sent;
		}
	}

unmask:
	sigprocmask(SIG_SETMASK, &oldmask, NULL);

	/*
	 * If signal is pending but we have already sent the whole packet to
	 * the server we need to return success status to allow a corresponding
	 * mid entry to be kept in the pending requests queue thus allowing
	 * to handle responses from the server by the client.
	 *
	 * If only part of the packet has been sent there is no need to hide
	 * interrupt because the session will be reconnected anyway, so there
	 * won't be any response from the server to handle.
	 */

	if (signal_pending(current) && (total_len != send_length)) {
		cifs_dbg(FYI, "signal is pending after attempt to send\n");
		rc = -EINTR;
	}

	/* uncork it */
	val = 0;
	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
				(char *)&val, sizeof(val));

	if ((total_len > 0) && (total_len != send_length)) {
		cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
			 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
		 * socket so the server throws away the partial SMB
		 */
		server->tcpStatus = CifsNeedReconnect;
		trace_smb3_partial_send_reconnect(server->CurrentMid,
						  server->hostname);
	}
smbd_done:
	if (rc < 0 && rc != -EINTR)
		cifs_dbg(VFS, "Error %d sending data on socket to server\n",
			 rc);
	else if (rc > 0)
		rc = 0;

	return rc;
}

static int
smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
	      struct smb_rqst *rqst, int flags)
{
	struct kvec iov;
	struct smb2_transform_hdr tr_hdr;
	struct smb_rqst cur_rqst[MAX_COMPOUND];
	int rc;

	if (!(flags & CIFS_TRANSFORM_REQ))
		return __smb_send_rqst(server, num_rqst, rqst);

	if (num_rqst > MAX_COMPOUND - 1)
		return -ENOMEM;

	memset(&cur_rqst[0], 0, sizeof(cur_rqst));
	memset(&iov, 0, sizeof(iov));
	memset(&tr_hdr, 0, sizeof(tr_hdr));

	iov.iov_base = &tr_hdr;
	iov.iov_len = sizeof(tr_hdr);
	cur_rqst[0].rq_iov = &iov;
	cur_rqst[0].rq_nvec = 1;

	if (!server->ops->init_transform_rq) {
		cifs_dbg(VFS, "Encryption requested but transform callback "
			 "is missing\n");
		return -EIO;
	}

	rc = server->ops->init_transform_rq(server, num_rqst + 1,
					    &cur_rqst[0], rqst);
	if (rc)
		return rc;

	rc = __smb_send_rqst(server, num_rqst + 1, &cur_rqst[0]);
	smb3_free_compound_rqst(num_rqst, &cur_rqst[1]);
	return rc;
}

int
smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
	 unsigned int smb_buf_length)
{
	struct kvec iov[2];
	struct smb_rqst rqst = { .rq_iov = iov,
				 .rq_nvec = 2 };

	iov[0].iov_base = smb_buffer;
	iov[0].iov_len = 4;
	iov[1].iov_base = (char *)smb_buffer + 4;
	iov[1].iov_len = smb_buf_length;

	return __smb_send_rqst(server, 1, &rqst);
}

static int
wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits,
		      const int timeout, const int flags,
		      unsigned int *instance)
{
	int rc;
	int *credits;
	int optype;
	long int t;

	if (timeout < 0)
		t = MAX_JIFFY_OFFSET;
	else
		t = msecs_to_jiffies(timeout);

	optype = flags & CIFS_OP_MASK;

	*instance = 0;

	credits = server->ops->get_credits_field(server, optype);
	/* Since an echo is already inflight, no need to wait to send another */
	if (*credits <= 0 && optype == CIFS_ECHO_OP)
		return -EAGAIN;

	spin_lock(&server->req_lock);
	if ((flags & CIFS_TIMEOUT_MASK) == CIFS_NON_BLOCKING) {
		/* oplock breaks must not be held up */
		server->in_flight++;
		*credits -= 1;
		*instance = server->reconnect_instance;
		spin_unlock(&server->req_lock);
		return 0;
	}

	while (1) {
		if (*credits < num_credits) {
			spin_unlock(&server->req_lock);
			cifs_num_waiters_inc(server);
			rc = wait_event_killable_timeout(server->request_q,
				has_credits(server, credits, num_credits), t);
			cifs_num_waiters_dec(server);
			if (!rc) {
				trace_smb3_credit_timeout(server->CurrentMid,
					server->hostname, num_credits);
				cifs_dbg(VFS, "wait timed out after %d ms\n",
					 timeout);
				return -ENOTSUPP;
			}
			if (rc == -ERESTARTSYS)
				return -ERESTARTSYS;
			spin_lock(&server->req_lock);
		} else {
			if (server->tcpStatus == CifsExiting) {
				spin_unlock(&server->req_lock);
				return -ENOENT;
			}

			/*
			 * For normal commands, reserve the last MAX_COMPOUND
			 * credits to compound requests.
			 * Otherwise these compounds could be permanently
			 * starved for credits by single-credit requests.
			 *
			 * To prevent spinning CPU, block this thread until
			 * there are >MAX_COMPOUND credits available.
			 * But only do this is we already have a lot of
			 * credits in flight to avoid triggering this check
			 * for servers that are slow to hand out credits on
			 * new sessions.
			 */
			if (!optype && num_credits == 1 &&
			    server->in_flight > 2 * MAX_COMPOUND &&
			    *credits <= MAX_COMPOUND) {
				spin_unlock(&server->req_lock);
				cifs_num_waiters_inc(server);
				rc = wait_event_killable_timeout(
					server->request_q,
					has_credits(server, credits,
						    MAX_COMPOUND + 1),
					t);
				cifs_num_waiters_dec(server);
				if (!rc) {
					trace_smb3_credit_timeout(
						server->CurrentMid,
						server->hostname, num_credits);
					cifs_dbg(VFS, "wait timed out after %d ms\n",
						 timeout);
					return -ENOTSUPP;
				}
				if (rc == -ERESTARTSYS)
					return -ERESTARTSYS;
				spin_lock(&server->req_lock);
				continue;
			}

			/*
			 * Can not count locking commands against total
			 * as they are allowed to block on server.
			 */

			/* update # of requests on the wire to server */
			if ((flags & CIFS_TIMEOUT_MASK) != CIFS_BLOCKING_OP) {
				*credits -= num_credits;
				server->in_flight += num_credits;
				*instance = server->reconnect_instance;
			}
			spin_unlock(&server->req_lock);
			break;
		}
	}
	return 0;
}

static int
wait_for_free_request(struct TCP_Server_Info *server, const int flags,
		      unsigned int *instance)
{
	return wait_for_free_credits(server, 1, -1, flags,
				     instance);
}

static int
wait_for_compound_request(struct TCP_Server_Info *server, int num,
			  const int flags, unsigned int *instance)
{
	int *credits;

	credits = server->ops->get_credits_field(server, flags & CIFS_OP_MASK);

	spin_lock(&server->req_lock);
	if (*credits < num) {
		/*
		 * Return immediately if not too many requests in flight since
		 * we will likely be stuck on waiting for credits.
		 */
		if (server->in_flight < num - *credits) {
			spin_unlock(&server->req_lock);
			return -ENOTSUPP;
		}
	}
	spin_unlock(&server->req_lock);

	return wait_for_free_credits(server, num, 60000, flags,
				     instance);
}
コード例 #2
0
ファイル: transport.c プロジェクト: AlexShiLucky/linux
static int
__smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
		struct smb_rqst *rqst)
{
	int rc = 0;
	struct kvec *iov;
	int n_vec;
	unsigned int send_length = 0;
	unsigned int i, j;
	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, rqst);
		goto smbd_done;
	}
	if (ssocket == NULL)
		return -ENOTSOCK;

	/* cork the socket */
	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
				(char *)&val, sizeof(val));

	for (j = 0; j < num_rqst; j++)
		send_length += smb_rqst_len(server, &rqst[j]);
	rfc1002_marker = cpu_to_be32(send_length);

	/* 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, &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);

	for (j = 0; j < num_rqst; j++) {
		iov = rqst[j].rq_iov;
		n_vec = rqst[j].rq_nvec;

		size = 0;
		for (i = 0; i < n_vec; i++) {
			dump_smb(iov[i].iov_base, iov[i].iov_len);
			size += iov[i].iov_len;
		}

		iov_iter_kvec(&smb_msg.msg_iter, WRITE, iov, n_vec, size);

		rc = smb_send_kvec(server, &smb_msg, &sent);
		if (rc < 0)
			goto uncork;

		total_len += sent;

		/* now walk the page array and send each page in it */
		for (i = 0; i < rqst[j].rq_npages; i++) {
			struct bio_vec bvec;

			bvec.bv_page = rqst[j].rq_pages[i];
			rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
					     &bvec.bv_offset);

			iov_iter_bvec(&smb_msg.msg_iter, WRITE,
				      &bvec, 1, bvec.bv_len);
			rc = smb_send_kvec(server, &smb_msg, &sent);
			if (rc < 0)
				break;

			total_len += sent;
		}
	}

uncork:
	/* uncork it */
	val = 0;
	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
				(char *)&val, sizeof(val));

	if ((total_len > 0) && (total_len != send_length)) {
		cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
			 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
		 * socket so the server throws away the partial SMB
		 */
		server->tcpStatus = CifsNeedReconnect;
		trace_smb3_partial_send_reconnect(server->CurrentMid,
						  server->hostname);
	}
smbd_done:
	if (rc < 0 && rc != -EINTR)
		cifs_dbg(VFS, "Error %d sending data on socket to server\n",
			 rc);
	else if (rc > 0)
		rc = 0;

	return rc;
}

static int
smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
	      struct smb_rqst *rqst, int flags)
{
	struct kvec iov;
	struct smb2_transform_hdr tr_hdr;
	struct smb_rqst cur_rqst[MAX_COMPOUND];
	int rc;

	if (!(flags & CIFS_TRANSFORM_REQ))
		return __smb_send_rqst(server, num_rqst, rqst);

	if (num_rqst > MAX_COMPOUND - 1)
		return -ENOMEM;

	memset(&cur_rqst[0], 0, sizeof(cur_rqst));
	memset(&iov, 0, sizeof(iov));
	memset(&tr_hdr, 0, sizeof(tr_hdr));

	iov.iov_base = &tr_hdr;
	iov.iov_len = sizeof(tr_hdr);
	cur_rqst[0].rq_iov = &iov;
	cur_rqst[0].rq_nvec = 1;

	if (!server->ops->init_transform_rq) {
		cifs_dbg(VFS, "Encryption requested but transform callback "
			 "is missing\n");
		return -EIO;
	}

	rc = server->ops->init_transform_rq(server, num_rqst + 1,
					    &cur_rqst[0], rqst);
	if (rc)
		return rc;

	rc = __smb_send_rqst(server, num_rqst + 1, &cur_rqst[0]);
	smb3_free_compound_rqst(num_rqst, &cur_rqst[1]);
	return rc;
}

int
smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
	 unsigned int smb_buf_length)
{
	struct kvec iov[2];
	struct smb_rqst rqst = { .rq_iov = iov,
				 .rq_nvec = 2 };

	iov[0].iov_base = smb_buffer;
	iov[0].iov_len = 4;
	iov[1].iov_base = (char *)smb_buffer + 4;
	iov[1].iov_len = smb_buf_length;

	return __smb_send_rqst(server, 1, &rqst);
}

static int
wait_for_free_credits(struct TCP_Server_Info *server, const int timeout,
		      int *credits)
{
	int rc;

	spin_lock(&server->req_lock);
	if (timeout == CIFS_ASYNC_OP) {
		/* oplock breaks must not be held up */
		server->in_flight++;
		*credits -= 1;
		spin_unlock(&server->req_lock);
		return 0;
	}

	while (1) {
		if (*credits <= 0) {
			spin_unlock(&server->req_lock);
			cifs_num_waiters_inc(server);
			rc = wait_event_killable(server->request_q,
						 has_credits(server, credits));
			cifs_num_waiters_dec(server);
			if (rc)
				return rc;
			spin_lock(&server->req_lock);
		} else {
			if (server->tcpStatus == CifsExiting) {
				spin_unlock(&server->req_lock);
				return -ENOENT;
			}

			/*
			 * Can not count locking commands against total
			 * as they are allowed to block on server.
			 */

			/* update # of requests on the wire to server */
			if (timeout != CIFS_BLOCKING_OP) {
				*credits -= 1;
				server->in_flight++;
			}
			spin_unlock(&server->req_lock);
			break;
		}
	}
	return 0;
}

static int
wait_for_free_request(struct TCP_Server_Info *server, const int timeout,
		      const int optype)
{
	int *val;

	val = server->ops->get_credits_field(server, optype);
	/* Since an echo is already inflight, no need to wait to send another */
	if (*val <= 0 && optype == CIFS_ECHO_OP)
		return -EAGAIN;
	return wait_for_free_credits(server, timeout, val);
}