4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 * Jeremy Allison (jra@samba.org) 2006.
8 * This library is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU Lesser General Public License as published
10 * by the Free Software Foundation; either version 2.1 of the License, or
11 * (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
16 * the GNU Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include <linux/list.h>
25 #include <linux/gfp.h>
26 #include <linux/wait.h>
27 #include <linux/net.h>
28 #include <linux/delay.h>
29 #include <linux/freezer.h>
30 #include <linux/tcp.h>
31 #include <linux/bvec.h>
32 #include <linux/highmem.h>
33 #include <linux/uaccess.h>
34 #include <asm/processor.h>
35 #include <linux/mempool.h>
38 #include "cifsproto.h"
39 #include "cifs_debug.h"
40 #include "smb2proto.h"
41 #include "smbdirect.h"
43 /* Max number of iovectors we can use off the stack when sending requests. */
44 #define CIFS_MAX_IOV_SIZE 8
47 cifs_wake_up_task(struct mid_q_entry *mid)
49 wake_up_process(mid->callback_data);
53 AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
55 struct mid_q_entry *temp;
58 cifs_dbg(VFS, "Null TCP session in AllocMidQEntry\n");
62 temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
63 memset(temp, 0, sizeof(struct mid_q_entry));
64 temp->mid = get_mid(smb_buffer);
65 temp->pid = current->pid;
66 temp->command = cpu_to_le16(smb_buffer->Command);
67 cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
68 /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
69 /* when mid allocated can be before when sent */
70 temp->when_alloc = jiffies;
71 temp->server = server;
74 * The default is for the mid to be synchronous, so the
75 * default callback just wakes up the current task.
77 temp->callback = cifs_wake_up_task;
78 temp->callback_data = current;
80 atomic_inc(&midCount);
81 temp->mid_state = MID_REQUEST_ALLOCATED;
86 DeleteMidQEntry(struct mid_q_entry *midEntry)
88 #ifdef CONFIG_CIFS_STATS2
89 __le16 command = midEntry->server->vals->lock_cmd;
92 midEntry->mid_state = MID_FREE;
93 atomic_dec(&midCount);
94 if (midEntry->large_buf)
95 cifs_buf_release(midEntry->resp_buf);
97 cifs_small_buf_release(midEntry->resp_buf);
98 #ifdef CONFIG_CIFS_STATS2
100 /* commands taking longer than one second are indications that
101 something is wrong, unless it is quite a slow link or server */
102 if (time_after(now, midEntry->when_alloc + HZ)) {
103 if ((cifsFYI & CIFS_TIMER) && (midEntry->command != command)) {
104 pr_debug(" CIFS slow rsp: cmd %d mid %llu",
105 midEntry->command, midEntry->mid);
106 pr_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
107 now - midEntry->when_alloc,
108 now - midEntry->when_sent,
109 now - midEntry->when_received);
113 mempool_free(midEntry, cifs_mid_poolp);
117 cifs_delete_mid(struct mid_q_entry *mid)
119 spin_lock(&GlobalMid_Lock);
120 list_del(&mid->qhead);
121 spin_unlock(&GlobalMid_Lock);
123 DeleteMidQEntry(mid);
127 * smb_send_kvec - send an array of kvecs to the server
128 * @server: Server to send the data to
129 * @smb_msg: Message to send
130 * @sent: amount of data sent on socket is stored here
132 * Our basic "send data to server" function. Should be called with srv_mutex
133 * held. The caller is responsible for handling the results.
136 smb_send_kvec(struct TCP_Server_Info *server, struct msghdr *smb_msg,
141 struct socket *ssocket = server->ssocket;
145 smb_msg->msg_name = (struct sockaddr *) &server->dstaddr;
146 smb_msg->msg_namelen = sizeof(struct sockaddr);
147 smb_msg->msg_control = NULL;
148 smb_msg->msg_controllen = 0;
149 if (server->noblocksnd)
150 smb_msg->msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL;
152 smb_msg->msg_flags = MSG_NOSIGNAL;
154 while (msg_data_left(smb_msg)) {
156 * If blocking send, we try 3 times, since each can block
157 * for 5 seconds. For nonblocking we have to try more
158 * but wait increasing amounts of time allowing time for
159 * socket to clear. The overall time we wait in either
160 * case to send on the socket is about 15 seconds.
161 * Similarly we wait for 15 seconds for a response from
162 * the server in SendReceive[2] for the server to send
163 * a response back for most types of requests (except
164 * SMB Write past end of file which can be slow, and
165 * blocking lock operations). NFS waits slightly longer
166 * than CIFS, but this can make it take longer for
167 * nonresponsive servers to be detected and 15 seconds
168 * is more than enough time for modern networks to
169 * send a packet. In most cases if we fail to send
170 * after the retries we will kill the socket and
171 * reconnect which may clear the network problem.
173 rc = sock_sendmsg(ssocket, smb_msg);
177 (!server->noblocksnd && (retries > 2))) {
178 cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
182 msleep(1 << retries);
190 /* should never happen, letting socket clear before
191 retrying is our only obvious option here */
192 cifs_dbg(VFS, "tcp sent no data\n");
197 /* send was at least partially successful */
199 retries = 0; /* in case we get ENOSPC on the next send */
205 rqst_len(struct smb_rqst *rqst)
208 struct kvec *iov = rqst->rq_iov;
209 unsigned long buflen = 0;
211 /* total up iov array first */
212 for (i = 0; i < rqst->rq_nvec; i++)
213 buflen += iov[i].iov_len;
215 /* add in the page array if there is one */
216 if (rqst->rq_npages) {
217 buflen += rqst->rq_pagesz * (rqst->rq_npages - 1);
218 buflen += rqst->rq_tailsz;
225 __smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
228 struct kvec *iov = rqst->rq_iov;
229 int n_vec = rqst->rq_nvec;
230 unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);
231 unsigned long send_length;
233 size_t total_len = 0, sent, size;
234 struct socket *ssocket = server->ssocket;
235 struct msghdr smb_msg;
237 if (cifs_rdma_enabled(server) && server->smbd_conn) {
238 rc = smbd_send(server->smbd_conn, rqst);
244 /* sanity check send length */
245 send_length = rqst_len(rqst);
246 if (send_length != smb_buf_length + 4) {
247 WARN(1, "Send length mismatch(send_length=%lu smb_buf_length=%u)\n",
248 send_length, smb_buf_length);
255 cifs_dbg(FYI, "Sending smb: smb_len=%u\n", smb_buf_length);
256 dump_smb(iov[0].iov_base, iov[0].iov_len);
257 dump_smb(iov[1].iov_base, iov[1].iov_len);
259 /* cork the socket */
260 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
261 (char *)&val, sizeof(val));
264 for (i = 0; i < n_vec; i++)
265 size += iov[i].iov_len;
267 iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC, iov, n_vec, size);
269 rc = smb_send_kvec(server, &smb_msg, &sent);
275 /* now walk the page array and send each page in it */
276 for (i = 0; i < rqst->rq_npages; i++) {
277 size_t len = i == rqst->rq_npages - 1
280 struct bio_vec bvec = {
281 .bv_page = rqst->rq_pages[i],
284 iov_iter_bvec(&smb_msg.msg_iter, WRITE | ITER_BVEC,
286 rc = smb_send_kvec(server, &smb_msg, &sent);
296 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
297 (char *)&val, sizeof(val));
299 if ((total_len > 0) && (total_len != smb_buf_length + 4)) {
300 cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
301 smb_buf_length + 4, total_len);
303 * If we have only sent part of an SMB then the next SMB could
304 * be taken as the remainder of this one. We need to kill the
305 * socket so the server throws away the partial SMB
307 server->tcpStatus = CifsNeedReconnect;
310 if (rc < 0 && rc != -EINTR)
311 cifs_dbg(VFS, "Error %d sending data on socket to server\n",
320 smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst, int flags)
322 struct smb_rqst cur_rqst;
325 if (!(flags & CIFS_TRANSFORM_REQ))
326 return __smb_send_rqst(server, rqst);
328 if (!server->ops->init_transform_rq ||
329 !server->ops->free_transform_rq) {
330 cifs_dbg(VFS, "Encryption requested but transform callbacks are missed\n");
334 rc = server->ops->init_transform_rq(server, &cur_rqst, rqst);
338 rc = __smb_send_rqst(server, &cur_rqst);
339 server->ops->free_transform_rq(&cur_rqst);
344 smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
345 unsigned int smb_buf_length)
348 struct smb_rqst rqst = { .rq_iov = iov,
351 iov[0].iov_base = smb_buffer;
353 iov[1].iov_base = (char *)smb_buffer + 4;
354 iov[1].iov_len = smb_buf_length;
356 return __smb_send_rqst(server, &rqst);
360 wait_for_free_credits(struct TCP_Server_Info *server, const int timeout,
365 spin_lock(&server->req_lock);
366 if (timeout == CIFS_ASYNC_OP) {
367 /* oplock breaks must not be held up */
370 spin_unlock(&server->req_lock);
376 spin_unlock(&server->req_lock);
377 cifs_num_waiters_inc(server);
378 rc = wait_event_killable(server->request_q,
379 has_credits(server, credits));
380 cifs_num_waiters_dec(server);
383 spin_lock(&server->req_lock);
385 if (server->tcpStatus == CifsExiting) {
386 spin_unlock(&server->req_lock);
391 * Can not count locking commands against total
392 * as they are allowed to block on server.
395 /* update # of requests on the wire to server */
396 if (timeout != CIFS_BLOCKING_OP) {
400 spin_unlock(&server->req_lock);
408 wait_for_free_request(struct TCP_Server_Info *server, const int timeout,
413 val = server->ops->get_credits_field(server, optype);
414 /* Since an echo is already inflight, no need to wait to send another */
415 if (*val <= 0 && optype == CIFS_ECHO_OP)
417 return wait_for_free_credits(server, timeout, val);
421 cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
422 unsigned int *num, unsigned int *credits)
429 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
430 struct mid_q_entry **ppmidQ)
432 if (ses->server->tcpStatus == CifsExiting) {
436 if (ses->server->tcpStatus == CifsNeedReconnect) {
437 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
441 if (ses->status == CifsNew) {
442 if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
443 (in_buf->Command != SMB_COM_NEGOTIATE))
445 /* else ok - we are setting up session */
448 if (ses->status == CifsExiting) {
449 /* check if SMB session is bad because we are setting it up */
450 if (in_buf->Command != SMB_COM_LOGOFF_ANDX)
452 /* else ok - we are shutting down session */
455 *ppmidQ = AllocMidQEntry(in_buf, ses->server);
458 spin_lock(&GlobalMid_Lock);
459 list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q);
460 spin_unlock(&GlobalMid_Lock);
465 wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
469 error = wait_event_freezekillable_unsafe(server->response_q,
470 midQ->mid_state != MID_REQUEST_SUBMITTED);
478 cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
481 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
482 struct mid_q_entry *mid;
484 if (rqst->rq_iov[0].iov_len != 4 ||
485 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
486 return ERR_PTR(-EIO);
488 /* enable signing if server requires it */
490 hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
492 mid = AllocMidQEntry(hdr, server);
494 return ERR_PTR(-ENOMEM);
496 rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
498 DeleteMidQEntry(mid);
506 * Send a SMB request and set the callback function in the mid to handle
507 * the result. Caller is responsible for dealing with timeouts.
510 cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
511 mid_receive_t *receive, mid_callback_t *callback,
512 mid_handle_t *handle, void *cbdata, const int flags)
514 int rc, timeout, optype;
515 struct mid_q_entry *mid;
516 unsigned int credits = 0;
518 timeout = flags & CIFS_TIMEOUT_MASK;
519 optype = flags & CIFS_OP_MASK;
521 if ((flags & CIFS_HAS_CREDITS) == 0) {
522 rc = wait_for_free_request(server, timeout, optype);
528 mutex_lock(&server->srv_mutex);
529 mid = server->ops->setup_async_request(server, rqst);
531 mutex_unlock(&server->srv_mutex);
532 add_credits_and_wake_if(server, credits, optype);
536 mid->receive = receive;
537 mid->callback = callback;
538 mid->callback_data = cbdata;
539 mid->handle = handle;
540 mid->mid_state = MID_REQUEST_SUBMITTED;
542 /* put it on the pending_mid_q */
543 spin_lock(&GlobalMid_Lock);
544 list_add_tail(&mid->qhead, &server->pending_mid_q);
545 spin_unlock(&GlobalMid_Lock);
548 * Need to store the time in mid before calling I/O. For call_async,
549 * I/O response may come back and free the mid entry on another thread.
551 cifs_save_when_sent(mid);
552 cifs_in_send_inc(server);
553 rc = smb_send_rqst(server, rqst, flags);
554 cifs_in_send_dec(server);
557 server->sequence_number -= 2;
558 cifs_delete_mid(mid);
561 mutex_unlock(&server->srv_mutex);
566 add_credits_and_wake_if(server, credits, optype);
572 * Send an SMB Request. No response info (other than return code)
573 * needs to be parsed.
575 * flags indicate the type of request buffer and how long to wait
576 * and whether to log NT STATUS code (error) before mapping it to POSIX error
580 SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
581 char *in_buf, int flags)
588 iov[0].iov_base = in_buf;
589 iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
590 flags |= CIFS_NO_RESP;
591 rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
592 cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
598 cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
602 cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n",
603 __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state);
605 spin_lock(&GlobalMid_Lock);
606 switch (mid->mid_state) {
607 case MID_RESPONSE_RECEIVED:
608 spin_unlock(&GlobalMid_Lock);
610 case MID_RETRY_NEEDED:
613 case MID_RESPONSE_MALFORMED:
620 list_del_init(&mid->qhead);
621 cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
622 __func__, mid->mid, mid->mid_state);
625 spin_unlock(&GlobalMid_Lock);
627 DeleteMidQEntry(mid);
632 send_cancel(struct TCP_Server_Info *server, struct smb_rqst *rqst,
633 struct mid_q_entry *mid)
635 return server->ops->send_cancel ?
636 server->ops->send_cancel(server, rqst, mid) : 0;
640 cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
643 unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
645 dump_smb(mid->resp_buf, min_t(u32, 92, len));
647 /* convert the length into a more usable form */
651 struct smb_rqst rqst = { .rq_iov = iov,
654 iov[0].iov_base = mid->resp_buf;
656 iov[1].iov_base = (char *)mid->resp_buf + 4;
657 iov[1].iov_len = len - 4;
658 /* FIXME: add code to kill session */
659 rc = cifs_verify_signature(&rqst, server,
660 mid->sequence_number);
662 cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
666 /* BB special case reconnect tid and uid here? */
667 return map_smb_to_linux_error(mid->resp_buf, log_error);
671 cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
674 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
675 struct mid_q_entry *mid;
677 if (rqst->rq_iov[0].iov_len != 4 ||
678 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
679 return ERR_PTR(-EIO);
681 rc = allocate_mid(ses, hdr, &mid);
684 rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
686 cifs_delete_mid(mid);
693 cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
694 struct smb_rqst *rqst, int *resp_buf_type, const int flags,
695 struct kvec *resp_iov)
699 struct mid_q_entry *midQ;
700 unsigned int credits = 1;
703 timeout = flags & CIFS_TIMEOUT_MASK;
704 optype = flags & CIFS_OP_MASK;
706 *resp_buf_type = CIFS_NO_BUFFER; /* no response buf yet */
708 if ((ses == NULL) || (ses->server == NULL)) {
709 cifs_dbg(VFS, "Null session\n");
713 if (ses->server->tcpStatus == CifsExiting)
717 * Ensure that we do not send more than 50 overlapping requests
718 * to the same server. We may make this configurable later or
722 rc = wait_for_free_request(ses->server, timeout, optype);
727 * Make sure that we sign in the same order that we send on this socket
728 * and avoid races inside tcp sendmsg code that could cause corruption
732 mutex_lock(&ses->server->srv_mutex);
734 midQ = ses->server->ops->setup_request(ses, rqst);
736 mutex_unlock(&ses->server->srv_mutex);
737 /* Update # of requests on wire to server */
738 add_credits(ses->server, 1, optype);
739 return PTR_ERR(midQ);
742 midQ->mid_state = MID_REQUEST_SUBMITTED;
743 cifs_in_send_inc(ses->server);
744 rc = smb_send_rqst(ses->server, rqst, flags);
745 cifs_in_send_dec(ses->server);
746 cifs_save_when_sent(midQ);
749 ses->server->sequence_number -= 2;
750 mutex_unlock(&ses->server->srv_mutex);
755 #ifdef CONFIG_CIFS_SMB311
756 if (ses->status == CifsNew)
757 smb311_update_preauth_hash(ses, rqst->rq_iov+1,
761 if (timeout == CIFS_ASYNC_OP)
764 rc = wait_for_response(ses->server, midQ);
766 cifs_dbg(FYI, "Cancelling wait for mid %llu\n", midQ->mid);
767 send_cancel(ses->server, rqst, midQ);
768 spin_lock(&GlobalMid_Lock);
769 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
770 midQ->mid_flags |= MID_WAIT_CANCELLED;
771 midQ->callback = DeleteMidQEntry;
772 spin_unlock(&GlobalMid_Lock);
773 add_credits(ses->server, 1, optype);
776 spin_unlock(&GlobalMid_Lock);
779 rc = cifs_sync_mid_result(midQ, ses->server);
781 add_credits(ses->server, 1, optype);
785 if (!midQ->resp_buf || midQ->mid_state != MID_RESPONSE_RECEIVED) {
787 cifs_dbg(FYI, "Bad MID state?\n");
791 buf = (char *)midQ->resp_buf;
792 resp_iov->iov_base = buf;
793 resp_iov->iov_len = midQ->resp_buf_size +
794 ses->server->vals->header_preamble_size;
796 *resp_buf_type = CIFS_LARGE_BUFFER;
798 *resp_buf_type = CIFS_SMALL_BUFFER;
800 #ifdef CONFIG_CIFS_SMB311
801 if (ses->status == CifsNew) {
804 .iov_len = get_rfc1002_length(buf)
806 smb311_update_preauth_hash(ses, &iov, 1);
810 credits = ses->server->ops->get_credits(midQ);
812 rc = ses->server->ops->check_receive(midQ, ses->server,
813 flags & CIFS_LOG_ERROR);
815 /* mark it so buf will not be freed by cifs_delete_mid */
816 if ((flags & CIFS_NO_RESP) == 0)
817 midQ->resp_buf = NULL;
819 cifs_delete_mid(midQ);
820 add_credits(ses->server, credits, optype);
826 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
827 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
828 const int flags, struct kvec *resp_iov)
830 struct smb_rqst rqst;
831 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
834 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
835 new_iov = kmalloc(sizeof(struct kvec) * (n_vec + 1),
842 /* 1st iov is a RFC1001 length followed by the rest of the packet */
843 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
845 new_iov[0].iov_base = new_iov[1].iov_base;
846 new_iov[0].iov_len = 4;
847 new_iov[1].iov_base += 4;
848 new_iov[1].iov_len -= 4;
850 memset(&rqst, 0, sizeof(struct smb_rqst));
851 rqst.rq_iov = new_iov;
852 rqst.rq_nvec = n_vec + 1;
854 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
855 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
860 /* Like SendReceive2 but iov[0] does not contain an rfc1002 header */
862 smb2_send_recv(const unsigned int xid, struct cifs_ses *ses,
863 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
864 const int flags, struct kvec *resp_iov)
866 struct smb_rqst rqst;
867 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
871 __be32 rfc1002_marker;
873 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
874 new_iov = kmalloc(sizeof(struct kvec) * (n_vec + 1),
881 /* 1st iov is an RFC1002 Session Message length */
882 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
885 for (i = 1; i < n_vec + 1; i++)
886 count += new_iov[i].iov_len;
888 rfc1002_marker = cpu_to_be32(count);
890 new_iov[0].iov_base = &rfc1002_marker;
891 new_iov[0].iov_len = 4;
893 memset(&rqst, 0, sizeof(struct smb_rqst));
894 rqst.rq_iov = new_iov;
895 rqst.rq_nvec = n_vec + 1;
897 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
898 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
904 SendReceive(const unsigned int xid, struct cifs_ses *ses,
905 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
906 int *pbytes_returned, const int timeout)
909 struct mid_q_entry *midQ;
910 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
911 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
912 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
915 cifs_dbg(VFS, "Null smb session\n");
918 if (ses->server == NULL) {
919 cifs_dbg(VFS, "Null tcp session\n");
923 if (ses->server->tcpStatus == CifsExiting)
926 /* Ensure that we do not send more than 50 overlapping requests
927 to the same server. We may make this configurable later or
930 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
931 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
936 rc = wait_for_free_request(ses->server, timeout, 0);
940 /* make sure that we sign in the same order that we send on this socket
941 and avoid races inside tcp sendmsg code that could cause corruption
944 mutex_lock(&ses->server->srv_mutex);
946 rc = allocate_mid(ses, in_buf, &midQ);
948 mutex_unlock(&ses->server->srv_mutex);
949 /* Update # of requests on wire to server */
950 add_credits(ses->server, 1, 0);
954 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
956 mutex_unlock(&ses->server->srv_mutex);
960 midQ->mid_state = MID_REQUEST_SUBMITTED;
962 cifs_in_send_inc(ses->server);
963 rc = smb_send(ses->server, in_buf, len);
964 cifs_in_send_dec(ses->server);
965 cifs_save_when_sent(midQ);
968 ses->server->sequence_number -= 2;
970 mutex_unlock(&ses->server->srv_mutex);
975 if (timeout == CIFS_ASYNC_OP)
978 rc = wait_for_response(ses->server, midQ);
980 send_cancel(ses->server, &rqst, midQ);
981 spin_lock(&GlobalMid_Lock);
982 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
983 /* no longer considered to be "in-flight" */
984 midQ->callback = DeleteMidQEntry;
985 spin_unlock(&GlobalMid_Lock);
986 add_credits(ses->server, 1, 0);
989 spin_unlock(&GlobalMid_Lock);
992 rc = cifs_sync_mid_result(midQ, ses->server);
994 add_credits(ses->server, 1, 0);
998 if (!midQ->resp_buf || !out_buf ||
999 midQ->mid_state != MID_RESPONSE_RECEIVED) {
1001 cifs_dbg(VFS, "Bad MID state?\n");
1005 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1006 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1007 rc = cifs_check_receive(midQ, ses->server, 0);
1009 cifs_delete_mid(midQ);
1010 add_credits(ses->server, 1, 0);
1015 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
1016 blocking lock to return. */
1019 send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
1020 struct smb_hdr *in_buf,
1021 struct smb_hdr *out_buf)
1024 struct cifs_ses *ses = tcon->ses;
1025 LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
1027 /* We just modify the current in_buf to change
1028 the type of lock from LOCKING_ANDX_SHARED_LOCK
1029 or LOCKING_ANDX_EXCLUSIVE_LOCK to
1030 LOCKING_ANDX_CANCEL_LOCK. */
1032 pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
1034 pSMB->hdr.Mid = get_next_mid(ses->server);
1036 return SendReceive(xid, ses, in_buf, out_buf,
1037 &bytes_returned, 0);
1041 SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
1042 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1043 int *pbytes_returned)
1047 struct mid_q_entry *midQ;
1048 struct cifs_ses *ses;
1049 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1050 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1051 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1053 if (tcon == NULL || tcon->ses == NULL) {
1054 cifs_dbg(VFS, "Null smb session\n");
1059 if (ses->server == NULL) {
1060 cifs_dbg(VFS, "Null tcp session\n");
1064 if (ses->server->tcpStatus == CifsExiting)
1067 /* Ensure that we do not send more than 50 overlapping requests
1068 to the same server. We may make this configurable later or
1071 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1072 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1077 rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0);
1081 /* make sure that we sign in the same order that we send on this socket
1082 and avoid races inside tcp sendmsg code that could cause corruption
1085 mutex_lock(&ses->server->srv_mutex);
1087 rc = allocate_mid(ses, in_buf, &midQ);
1089 mutex_unlock(&ses->server->srv_mutex);
1093 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
1095 cifs_delete_mid(midQ);
1096 mutex_unlock(&ses->server->srv_mutex);
1100 midQ->mid_state = MID_REQUEST_SUBMITTED;
1101 cifs_in_send_inc(ses->server);
1102 rc = smb_send(ses->server, in_buf, len);
1103 cifs_in_send_dec(ses->server);
1104 cifs_save_when_sent(midQ);
1107 ses->server->sequence_number -= 2;
1109 mutex_unlock(&ses->server->srv_mutex);
1112 cifs_delete_mid(midQ);
1116 /* Wait for a reply - allow signals to interrupt. */
1117 rc = wait_event_interruptible(ses->server->response_q,
1118 (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
1119 ((ses->server->tcpStatus != CifsGood) &&
1120 (ses->server->tcpStatus != CifsNew)));
1122 /* Were we interrupted by a signal ? */
1123 if ((rc == -ERESTARTSYS) &&
1124 (midQ->mid_state == MID_REQUEST_SUBMITTED) &&
1125 ((ses->server->tcpStatus == CifsGood) ||
1126 (ses->server->tcpStatus == CifsNew))) {
1128 if (in_buf->Command == SMB_COM_TRANSACTION2) {
1129 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1130 blocking lock to return. */
1131 rc = send_cancel(ses->server, &rqst, midQ);
1133 cifs_delete_mid(midQ);
1137 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1138 to cause the blocking lock to return. */
1140 rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
1142 /* If we get -ENOLCK back the lock may have
1143 already been removed. Don't exit in this case. */
1144 if (rc && rc != -ENOLCK) {
1145 cifs_delete_mid(midQ);
1150 rc = wait_for_response(ses->server, midQ);
1152 send_cancel(ses->server, &rqst, midQ);
1153 spin_lock(&GlobalMid_Lock);
1154 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1155 /* no longer considered to be "in-flight" */
1156 midQ->callback = DeleteMidQEntry;
1157 spin_unlock(&GlobalMid_Lock);
1160 spin_unlock(&GlobalMid_Lock);
1163 /* We got the response - restart system call. */
1167 rc = cifs_sync_mid_result(midQ, ses->server);
1171 /* rcvd frame is ok */
1172 if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) {
1174 cifs_dbg(VFS, "Bad MID state?\n");
1178 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1179 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1180 rc = cifs_check_receive(midQ, ses->server, 0);
1182 cifs_delete_mid(midQ);
1183 if (rstart && rc == -EACCES)
1184 return -ERESTARTSYS;