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 "smbdirect.h"
42 /* Max number of iovectors we can use off the stack when sending requests. */
43 #define CIFS_MAX_IOV_SIZE 8
46 cifs_wake_up_task(struct mid_q_entry *mid)
48 wake_up_process(mid->callback_data);
52 AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
54 struct mid_q_entry *temp;
57 cifs_dbg(VFS, "Null TCP session in AllocMidQEntry\n");
61 temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
62 memset(temp, 0, sizeof(struct mid_q_entry));
63 temp->mid = get_mid(smb_buffer);
64 temp->pid = current->pid;
65 temp->command = cpu_to_le16(smb_buffer->Command);
66 cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
67 /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
68 /* when mid allocated can be before when sent */
69 temp->when_alloc = jiffies;
70 temp->server = server;
73 * The default is for the mid to be synchronous, so the
74 * default callback just wakes up the current task.
76 temp->callback = cifs_wake_up_task;
77 temp->callback_data = current;
79 atomic_inc(&midCount);
80 temp->mid_state = MID_REQUEST_ALLOCATED;
85 DeleteMidQEntry(struct mid_q_entry *midEntry)
87 #ifdef CONFIG_CIFS_STATS2
88 __le16 command = midEntry->server->vals->lock_cmd;
91 midEntry->mid_state = MID_FREE;
92 atomic_dec(&midCount);
93 if (midEntry->large_buf)
94 cifs_buf_release(midEntry->resp_buf);
96 cifs_small_buf_release(midEntry->resp_buf);
97 #ifdef CONFIG_CIFS_STATS2
99 /* commands taking longer than one second are indications that
100 something is wrong, unless it is quite a slow link or server */
101 if (time_after(now, midEntry->when_alloc + HZ)) {
102 if ((cifsFYI & CIFS_TIMER) && (midEntry->command != command)) {
103 pr_debug(" CIFS slow rsp: cmd %d mid %llu",
104 midEntry->command, midEntry->mid);
105 pr_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
106 now - midEntry->when_alloc,
107 now - midEntry->when_sent,
108 now - midEntry->when_received);
112 mempool_free(midEntry, cifs_mid_poolp);
116 cifs_delete_mid(struct mid_q_entry *mid)
118 spin_lock(&GlobalMid_Lock);
119 list_del(&mid->qhead);
120 spin_unlock(&GlobalMid_Lock);
122 DeleteMidQEntry(mid);
126 * smb_send_kvec - send an array of kvecs to the server
127 * @server: Server to send the data to
128 * @smb_msg: Message to send
129 * @sent: amount of data sent on socket is stored here
131 * Our basic "send data to server" function. Should be called with srv_mutex
132 * held. The caller is responsible for handling the results.
135 smb_send_kvec(struct TCP_Server_Info *server, struct msghdr *smb_msg,
140 struct socket *ssocket = server->ssocket;
144 smb_msg->msg_name = (struct sockaddr *) &server->dstaddr;
145 smb_msg->msg_namelen = sizeof(struct sockaddr);
146 smb_msg->msg_control = NULL;
147 smb_msg->msg_controllen = 0;
148 if (server->noblocksnd)
149 smb_msg->msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL;
151 smb_msg->msg_flags = MSG_NOSIGNAL;
153 while (msg_data_left(smb_msg)) {
155 * If blocking send, we try 3 times, since each can block
156 * for 5 seconds. For nonblocking we have to try more
157 * but wait increasing amounts of time allowing time for
158 * socket to clear. The overall time we wait in either
159 * case to send on the socket is about 15 seconds.
160 * Similarly we wait for 15 seconds for a response from
161 * the server in SendReceive[2] for the server to send
162 * a response back for most types of requests (except
163 * SMB Write past end of file which can be slow, and
164 * blocking lock operations). NFS waits slightly longer
165 * than CIFS, but this can make it take longer for
166 * nonresponsive servers to be detected and 15 seconds
167 * is more than enough time for modern networks to
168 * send a packet. In most cases if we fail to send
169 * after the retries we will kill the socket and
170 * reconnect which may clear the network problem.
172 rc = sock_sendmsg(ssocket, smb_msg);
176 (!server->noblocksnd && (retries > 2))) {
177 cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
181 msleep(1 << retries);
189 /* should never happen, letting socket clear before
190 retrying is our only obvious option here */
191 cifs_dbg(VFS, "tcp sent no data\n");
196 /* send was at least partially successful */
198 retries = 0; /* in case we get ENOSPC on the next send */
204 rqst_len(struct smb_rqst *rqst)
207 struct kvec *iov = rqst->rq_iov;
208 unsigned long buflen = 0;
210 /* total up iov array first */
211 for (i = 0; i < rqst->rq_nvec; i++)
212 buflen += iov[i].iov_len;
214 /* add in the page array if there is one */
215 if (rqst->rq_npages) {
216 buflen += rqst->rq_pagesz * (rqst->rq_npages - 1);
217 buflen += rqst->rq_tailsz;
224 __smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
227 struct kvec *iov = rqst->rq_iov;
228 int n_vec = rqst->rq_nvec;
229 unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);
230 unsigned long send_length;
232 size_t total_len = 0, sent, size;
233 struct socket *ssocket = server->ssocket;
234 struct msghdr smb_msg;
236 if (cifs_rdma_enabled(server) && server->smbd_conn) {
237 rc = smbd_send(server->smbd_conn, rqst);
243 /* sanity check send length */
244 send_length = rqst_len(rqst);
245 if (send_length != smb_buf_length + 4) {
246 WARN(1, "Send length mismatch(send_length=%lu smb_buf_length=%u)\n",
247 send_length, smb_buf_length);
254 cifs_dbg(FYI, "Sending smb: smb_len=%u\n", smb_buf_length);
255 dump_smb(iov[0].iov_base, iov[0].iov_len);
256 dump_smb(iov[1].iov_base, iov[1].iov_len);
258 /* cork the socket */
259 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
260 (char *)&val, sizeof(val));
263 for (i = 0; i < n_vec; i++)
264 size += iov[i].iov_len;
266 iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC, iov, n_vec, size);
268 rc = smb_send_kvec(server, &smb_msg, &sent);
274 /* now walk the page array and send each page in it */
275 for (i = 0; i < rqst->rq_npages; i++) {
276 size_t len = i == rqst->rq_npages - 1
279 struct bio_vec bvec = {
280 .bv_page = rqst->rq_pages[i],
283 iov_iter_bvec(&smb_msg.msg_iter, WRITE | ITER_BVEC,
285 rc = smb_send_kvec(server, &smb_msg, &sent);
295 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
296 (char *)&val, sizeof(val));
298 if ((total_len > 0) && (total_len != smb_buf_length + 4)) {
299 cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
300 smb_buf_length + 4, total_len);
302 * If we have only sent part of an SMB then the next SMB could
303 * be taken as the remainder of this one. We need to kill the
304 * socket so the server throws away the partial SMB
306 server->tcpStatus = CifsNeedReconnect;
309 if (rc < 0 && rc != -EINTR)
310 cifs_dbg(VFS, "Error %d sending data on socket to server\n",
319 smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst, int flags)
321 struct smb_rqst cur_rqst;
324 if (!(flags & CIFS_TRANSFORM_REQ))
325 return __smb_send_rqst(server, rqst);
327 if (!server->ops->init_transform_rq ||
328 !server->ops->free_transform_rq) {
329 cifs_dbg(VFS, "Encryption requested but transform callbacks are missed\n");
333 rc = server->ops->init_transform_rq(server, &cur_rqst, rqst);
337 rc = __smb_send_rqst(server, &cur_rqst);
338 server->ops->free_transform_rq(&cur_rqst);
343 smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
344 unsigned int smb_buf_length)
347 struct smb_rqst rqst = { .rq_iov = iov,
350 iov[0].iov_base = smb_buffer;
352 iov[1].iov_base = (char *)smb_buffer + 4;
353 iov[1].iov_len = smb_buf_length;
355 return __smb_send_rqst(server, &rqst);
359 wait_for_free_credits(struct TCP_Server_Info *server, const int timeout,
364 spin_lock(&server->req_lock);
365 if (timeout == CIFS_ASYNC_OP) {
366 /* oplock breaks must not be held up */
369 spin_unlock(&server->req_lock);
375 spin_unlock(&server->req_lock);
376 cifs_num_waiters_inc(server);
377 rc = wait_event_killable(server->request_q,
378 has_credits(server, credits));
379 cifs_num_waiters_dec(server);
382 spin_lock(&server->req_lock);
384 if (server->tcpStatus == CifsExiting) {
385 spin_unlock(&server->req_lock);
390 * Can not count locking commands against total
391 * as they are allowed to block on server.
394 /* update # of requests on the wire to server */
395 if (timeout != CIFS_BLOCKING_OP) {
399 spin_unlock(&server->req_lock);
407 wait_for_free_request(struct TCP_Server_Info *server, const int timeout,
412 val = server->ops->get_credits_field(server, optype);
413 /* Since an echo is already inflight, no need to wait to send another */
414 if (*val <= 0 && optype == CIFS_ECHO_OP)
416 return wait_for_free_credits(server, timeout, val);
420 cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
421 unsigned int *num, unsigned int *credits)
428 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
429 struct mid_q_entry **ppmidQ)
431 if (ses->server->tcpStatus == CifsExiting) {
435 if (ses->server->tcpStatus == CifsNeedReconnect) {
436 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
440 if (ses->status == CifsNew) {
441 if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
442 (in_buf->Command != SMB_COM_NEGOTIATE))
444 /* else ok - we are setting up session */
447 if (ses->status == CifsExiting) {
448 /* check if SMB session is bad because we are setting it up */
449 if (in_buf->Command != SMB_COM_LOGOFF_ANDX)
451 /* else ok - we are shutting down session */
454 *ppmidQ = AllocMidQEntry(in_buf, ses->server);
457 spin_lock(&GlobalMid_Lock);
458 list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q);
459 spin_unlock(&GlobalMid_Lock);
464 wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
468 error = wait_event_freezekillable_unsafe(server->response_q,
469 midQ->mid_state != MID_REQUEST_SUBMITTED);
477 cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
480 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
481 struct mid_q_entry *mid;
483 if (rqst->rq_iov[0].iov_len != 4 ||
484 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
485 return ERR_PTR(-EIO);
487 /* enable signing if server requires it */
489 hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
491 mid = AllocMidQEntry(hdr, server);
493 return ERR_PTR(-ENOMEM);
495 rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
497 DeleteMidQEntry(mid);
505 * Send a SMB request and set the callback function in the mid to handle
506 * the result. Caller is responsible for dealing with timeouts.
509 cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
510 mid_receive_t *receive, mid_callback_t *callback,
511 mid_handle_t *handle, void *cbdata, const int flags)
513 int rc, timeout, optype;
514 struct mid_q_entry *mid;
515 unsigned int credits = 0;
517 timeout = flags & CIFS_TIMEOUT_MASK;
518 optype = flags & CIFS_OP_MASK;
520 if ((flags & CIFS_HAS_CREDITS) == 0) {
521 rc = wait_for_free_request(server, timeout, optype);
527 mutex_lock(&server->srv_mutex);
528 mid = server->ops->setup_async_request(server, rqst);
530 mutex_unlock(&server->srv_mutex);
531 add_credits_and_wake_if(server, credits, optype);
535 mid->receive = receive;
536 mid->callback = callback;
537 mid->callback_data = cbdata;
538 mid->handle = handle;
539 mid->mid_state = MID_REQUEST_SUBMITTED;
541 /* put it on the pending_mid_q */
542 spin_lock(&GlobalMid_Lock);
543 list_add_tail(&mid->qhead, &server->pending_mid_q);
544 spin_unlock(&GlobalMid_Lock);
547 * Need to store the time in mid before calling I/O. For call_async,
548 * I/O response may come back and free the mid entry on another thread.
550 cifs_save_when_sent(mid);
551 cifs_in_send_inc(server);
552 rc = smb_send_rqst(server, rqst, flags);
553 cifs_in_send_dec(server);
556 server->sequence_number -= 2;
557 cifs_delete_mid(mid);
560 mutex_unlock(&server->srv_mutex);
565 add_credits_and_wake_if(server, credits, optype);
571 * Send an SMB Request. No response info (other than return code)
572 * needs to be parsed.
574 * flags indicate the type of request buffer and how long to wait
575 * and whether to log NT STATUS code (error) before mapping it to POSIX error
579 SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
580 char *in_buf, int flags)
587 iov[0].iov_base = in_buf;
588 iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
589 flags |= CIFS_NO_RESP;
590 rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
591 cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
597 cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
601 cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n",
602 __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state);
604 spin_lock(&GlobalMid_Lock);
605 switch (mid->mid_state) {
606 case MID_RESPONSE_RECEIVED:
607 spin_unlock(&GlobalMid_Lock);
609 case MID_RETRY_NEEDED:
612 case MID_RESPONSE_MALFORMED:
619 list_del_init(&mid->qhead);
620 cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
621 __func__, mid->mid, mid->mid_state);
624 spin_unlock(&GlobalMid_Lock);
626 DeleteMidQEntry(mid);
631 send_cancel(struct TCP_Server_Info *server, struct smb_rqst *rqst,
632 struct mid_q_entry *mid)
634 return server->ops->send_cancel ?
635 server->ops->send_cancel(server, rqst, mid) : 0;
639 cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
642 unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
644 dump_smb(mid->resp_buf, min_t(u32, 92, len));
646 /* convert the length into a more usable form */
650 struct smb_rqst rqst = { .rq_iov = iov,
653 iov[0].iov_base = mid->resp_buf;
655 iov[1].iov_base = (char *)mid->resp_buf + 4;
656 iov[1].iov_len = len - 4;
657 /* FIXME: add code to kill session */
658 rc = cifs_verify_signature(&rqst, server,
659 mid->sequence_number);
661 cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
665 /* BB special case reconnect tid and uid here? */
666 return map_smb_to_linux_error(mid->resp_buf, log_error);
670 cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
673 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
674 struct mid_q_entry *mid;
676 if (rqst->rq_iov[0].iov_len != 4 ||
677 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
678 return ERR_PTR(-EIO);
680 rc = allocate_mid(ses, hdr, &mid);
683 rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
685 cifs_delete_mid(mid);
692 cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
693 struct smb_rqst *rqst, int *resp_buf_type, const int flags,
694 struct kvec *resp_iov)
698 struct mid_q_entry *midQ;
699 unsigned int credits = 1;
702 timeout = flags & CIFS_TIMEOUT_MASK;
703 optype = flags & CIFS_OP_MASK;
705 *resp_buf_type = CIFS_NO_BUFFER; /* no response buf yet */
707 if ((ses == NULL) || (ses->server == NULL)) {
708 cifs_dbg(VFS, "Null session\n");
712 if (ses->server->tcpStatus == CifsExiting)
716 * Ensure that we do not send more than 50 overlapping requests
717 * to the same server. We may make this configurable later or
721 rc = wait_for_free_request(ses->server, timeout, optype);
726 * Make sure that we sign in the same order that we send on this socket
727 * and avoid races inside tcp sendmsg code that could cause corruption
731 mutex_lock(&ses->server->srv_mutex);
733 midQ = ses->server->ops->setup_request(ses, rqst);
735 mutex_unlock(&ses->server->srv_mutex);
736 /* Update # of requests on wire to server */
737 add_credits(ses->server, 1, optype);
738 return PTR_ERR(midQ);
741 midQ->mid_state = MID_REQUEST_SUBMITTED;
742 cifs_in_send_inc(ses->server);
743 rc = smb_send_rqst(ses->server, rqst, flags);
744 cifs_in_send_dec(ses->server);
745 cifs_save_when_sent(midQ);
748 ses->server->sequence_number -= 2;
749 mutex_unlock(&ses->server->srv_mutex);
754 if (timeout == CIFS_ASYNC_OP)
757 rc = wait_for_response(ses->server, midQ);
759 cifs_dbg(FYI, "Cancelling wait for mid %llu\n", midQ->mid);
760 send_cancel(ses->server, rqst, midQ);
761 spin_lock(&GlobalMid_Lock);
762 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
763 midQ->mid_flags |= MID_WAIT_CANCELLED;
764 midQ->callback = DeleteMidQEntry;
765 spin_unlock(&GlobalMid_Lock);
766 add_credits(ses->server, 1, optype);
769 spin_unlock(&GlobalMid_Lock);
772 rc = cifs_sync_mid_result(midQ, ses->server);
774 add_credits(ses->server, 1, optype);
778 if (!midQ->resp_buf || midQ->mid_state != MID_RESPONSE_RECEIVED) {
780 cifs_dbg(FYI, "Bad MID state?\n");
784 buf = (char *)midQ->resp_buf;
785 resp_iov->iov_base = buf;
786 resp_iov->iov_len = get_rfc1002_length(buf) + 4;
788 *resp_buf_type = CIFS_LARGE_BUFFER;
790 *resp_buf_type = CIFS_SMALL_BUFFER;
792 credits = ses->server->ops->get_credits(midQ);
794 rc = ses->server->ops->check_receive(midQ, ses->server,
795 flags & CIFS_LOG_ERROR);
797 /* mark it so buf will not be freed by cifs_delete_mid */
798 if ((flags & CIFS_NO_RESP) == 0)
799 midQ->resp_buf = NULL;
801 cifs_delete_mid(midQ);
802 add_credits(ses->server, credits, optype);
808 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
809 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
810 const int flags, struct kvec *resp_iov)
812 struct smb_rqst rqst;
813 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
816 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
817 new_iov = kmalloc(sizeof(struct kvec) * (n_vec + 1),
824 /* 1st iov is a RFC1001 length followed by the rest of the packet */
825 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
827 new_iov[0].iov_base = new_iov[1].iov_base;
828 new_iov[0].iov_len = 4;
829 new_iov[1].iov_base += 4;
830 new_iov[1].iov_len -= 4;
832 memset(&rqst, 0, sizeof(struct smb_rqst));
833 rqst.rq_iov = new_iov;
834 rqst.rq_nvec = n_vec + 1;
836 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
837 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
842 /* Like SendReceive2 but iov[0] does not contain an rfc1002 header */
844 smb2_send_recv(const unsigned int xid, struct cifs_ses *ses,
845 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
846 const int flags, struct kvec *resp_iov)
848 struct smb_rqst rqst;
849 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
853 __be32 rfc1002_marker;
855 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
856 new_iov = kmalloc(sizeof(struct kvec) * (n_vec + 1),
863 /* 1st iov is an RFC1002 Session Message length */
864 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
867 for (i = 1; i < n_vec + 1; i++)
868 count += new_iov[i].iov_len;
870 rfc1002_marker = cpu_to_be32(count);
872 new_iov[0].iov_base = &rfc1002_marker;
873 new_iov[0].iov_len = 4;
875 memset(&rqst, 0, sizeof(struct smb_rqst));
876 rqst.rq_iov = new_iov;
877 rqst.rq_nvec = n_vec + 1;
879 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
880 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
886 SendReceive(const unsigned int xid, struct cifs_ses *ses,
887 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
888 int *pbytes_returned, const int timeout)
891 struct mid_q_entry *midQ;
892 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
893 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
894 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
897 cifs_dbg(VFS, "Null smb session\n");
900 if (ses->server == NULL) {
901 cifs_dbg(VFS, "Null tcp session\n");
905 if (ses->server->tcpStatus == CifsExiting)
908 /* Ensure that we do not send more than 50 overlapping requests
909 to the same server. We may make this configurable later or
912 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
913 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
918 rc = wait_for_free_request(ses->server, timeout, 0);
922 /* make sure that we sign in the same order that we send on this socket
923 and avoid races inside tcp sendmsg code that could cause corruption
926 mutex_lock(&ses->server->srv_mutex);
928 rc = allocate_mid(ses, in_buf, &midQ);
930 mutex_unlock(&ses->server->srv_mutex);
931 /* Update # of requests on wire to server */
932 add_credits(ses->server, 1, 0);
936 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
938 mutex_unlock(&ses->server->srv_mutex);
942 midQ->mid_state = MID_REQUEST_SUBMITTED;
944 cifs_in_send_inc(ses->server);
945 rc = smb_send(ses->server, in_buf, len);
946 cifs_in_send_dec(ses->server);
947 cifs_save_when_sent(midQ);
950 ses->server->sequence_number -= 2;
952 mutex_unlock(&ses->server->srv_mutex);
957 if (timeout == CIFS_ASYNC_OP)
960 rc = wait_for_response(ses->server, midQ);
962 send_cancel(ses->server, &rqst, midQ);
963 spin_lock(&GlobalMid_Lock);
964 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
965 /* no longer considered to be "in-flight" */
966 midQ->callback = DeleteMidQEntry;
967 spin_unlock(&GlobalMid_Lock);
968 add_credits(ses->server, 1, 0);
971 spin_unlock(&GlobalMid_Lock);
974 rc = cifs_sync_mid_result(midQ, ses->server);
976 add_credits(ses->server, 1, 0);
980 if (!midQ->resp_buf || !out_buf ||
981 midQ->mid_state != MID_RESPONSE_RECEIVED) {
983 cifs_dbg(VFS, "Bad MID state?\n");
987 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
988 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
989 rc = cifs_check_receive(midQ, ses->server, 0);
991 cifs_delete_mid(midQ);
992 add_credits(ses->server, 1, 0);
997 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
998 blocking lock to return. */
1001 send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
1002 struct smb_hdr *in_buf,
1003 struct smb_hdr *out_buf)
1006 struct cifs_ses *ses = tcon->ses;
1007 LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
1009 /* We just modify the current in_buf to change
1010 the type of lock from LOCKING_ANDX_SHARED_LOCK
1011 or LOCKING_ANDX_EXCLUSIVE_LOCK to
1012 LOCKING_ANDX_CANCEL_LOCK. */
1014 pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
1016 pSMB->hdr.Mid = get_next_mid(ses->server);
1018 return SendReceive(xid, ses, in_buf, out_buf,
1019 &bytes_returned, 0);
1023 SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
1024 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1025 int *pbytes_returned)
1029 struct mid_q_entry *midQ;
1030 struct cifs_ses *ses;
1031 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1032 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1033 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1035 if (tcon == NULL || tcon->ses == NULL) {
1036 cifs_dbg(VFS, "Null smb session\n");
1041 if (ses->server == NULL) {
1042 cifs_dbg(VFS, "Null tcp session\n");
1046 if (ses->server->tcpStatus == CifsExiting)
1049 /* Ensure that we do not send more than 50 overlapping requests
1050 to the same server. We may make this configurable later or
1053 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1054 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1059 rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0);
1063 /* make sure that we sign in the same order that we send on this socket
1064 and avoid races inside tcp sendmsg code that could cause corruption
1067 mutex_lock(&ses->server->srv_mutex);
1069 rc = allocate_mid(ses, in_buf, &midQ);
1071 mutex_unlock(&ses->server->srv_mutex);
1075 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
1077 cifs_delete_mid(midQ);
1078 mutex_unlock(&ses->server->srv_mutex);
1082 midQ->mid_state = MID_REQUEST_SUBMITTED;
1083 cifs_in_send_inc(ses->server);
1084 rc = smb_send(ses->server, in_buf, len);
1085 cifs_in_send_dec(ses->server);
1086 cifs_save_when_sent(midQ);
1089 ses->server->sequence_number -= 2;
1091 mutex_unlock(&ses->server->srv_mutex);
1094 cifs_delete_mid(midQ);
1098 /* Wait for a reply - allow signals to interrupt. */
1099 rc = wait_event_interruptible(ses->server->response_q,
1100 (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
1101 ((ses->server->tcpStatus != CifsGood) &&
1102 (ses->server->tcpStatus != CifsNew)));
1104 /* Were we interrupted by a signal ? */
1105 if ((rc == -ERESTARTSYS) &&
1106 (midQ->mid_state == MID_REQUEST_SUBMITTED) &&
1107 ((ses->server->tcpStatus == CifsGood) ||
1108 (ses->server->tcpStatus == CifsNew))) {
1110 if (in_buf->Command == SMB_COM_TRANSACTION2) {
1111 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1112 blocking lock to return. */
1113 rc = send_cancel(ses->server, &rqst, midQ);
1115 cifs_delete_mid(midQ);
1119 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1120 to cause the blocking lock to return. */
1122 rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
1124 /* If we get -ENOLCK back the lock may have
1125 already been removed. Don't exit in this case. */
1126 if (rc && rc != -ENOLCK) {
1127 cifs_delete_mid(midQ);
1132 rc = wait_for_response(ses->server, midQ);
1134 send_cancel(ses->server, &rqst, midQ);
1135 spin_lock(&GlobalMid_Lock);
1136 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1137 /* no longer considered to be "in-flight" */
1138 midQ->callback = DeleteMidQEntry;
1139 spin_unlock(&GlobalMid_Lock);
1142 spin_unlock(&GlobalMid_Lock);
1145 /* We got the response - restart system call. */
1149 rc = cifs_sync_mid_result(midQ, ses->server);
1153 /* rcvd frame is ok */
1154 if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) {
1156 cifs_dbg(VFS, "Bad MID state?\n");
1160 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1161 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1162 rc = cifs_check_receive(midQ, ses->server, 0);
1164 cifs_delete_mid(midQ);
1165 if (rstart && rc == -EACCES)
1166 return -ERESTARTSYS;