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 kref_init(&temp->refcount);
65 temp->mid = get_mid(smb_buffer);
66 temp->pid = current->pid;
67 temp->command = cpu_to_le16(smb_buffer->Command);
68 cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
69 /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
70 /* when mid allocated can be before when sent */
71 temp->when_alloc = jiffies;
72 temp->server = server;
75 * The default is for the mid to be synchronous, so the
76 * default callback just wakes up the current task.
78 temp->callback = cifs_wake_up_task;
79 temp->callback_data = current;
81 atomic_inc(&midCount);
82 temp->mid_state = MID_REQUEST_ALLOCATED;
86 static void _cifs_mid_q_entry_release(struct kref *refcount)
88 struct mid_q_entry *mid = container_of(refcount, struct mid_q_entry,
91 mempool_free(mid, cifs_mid_poolp);
94 void cifs_mid_q_entry_release(struct mid_q_entry *midEntry)
96 spin_lock(&GlobalMid_Lock);
97 kref_put(&midEntry->refcount, _cifs_mid_q_entry_release);
98 spin_unlock(&GlobalMid_Lock);
102 DeleteMidQEntry(struct mid_q_entry *midEntry)
104 #ifdef CONFIG_CIFS_STATS2
105 __le16 command = midEntry->server->vals->lock_cmd;
108 midEntry->mid_state = MID_FREE;
109 atomic_dec(&midCount);
110 if (midEntry->large_buf)
111 cifs_buf_release(midEntry->resp_buf);
113 cifs_small_buf_release(midEntry->resp_buf);
114 #ifdef CONFIG_CIFS_STATS2
116 /* commands taking longer than one second are indications that
117 something is wrong, unless it is quite a slow link or server */
118 if (time_after(now, midEntry->when_alloc + HZ)) {
119 if ((cifsFYI & CIFS_TIMER) && (midEntry->command != command)) {
120 pr_debug(" CIFS slow rsp: cmd %d mid %llu",
121 midEntry->command, midEntry->mid);
122 pr_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
123 now - midEntry->when_alloc,
124 now - midEntry->when_sent,
125 now - midEntry->when_received);
129 cifs_mid_q_entry_release(midEntry);
133 cifs_delete_mid(struct mid_q_entry *mid)
135 spin_lock(&GlobalMid_Lock);
136 list_del(&mid->qhead);
137 spin_unlock(&GlobalMid_Lock);
139 DeleteMidQEntry(mid);
143 * smb_send_kvec - send an array of kvecs to the server
144 * @server: Server to send the data to
145 * @smb_msg: Message to send
146 * @sent: amount of data sent on socket is stored here
148 * Our basic "send data to server" function. Should be called with srv_mutex
149 * held. The caller is responsible for handling the results.
152 smb_send_kvec(struct TCP_Server_Info *server, struct msghdr *smb_msg,
157 struct socket *ssocket = server->ssocket;
161 smb_msg->msg_name = (struct sockaddr *) &server->dstaddr;
162 smb_msg->msg_namelen = sizeof(struct sockaddr);
163 smb_msg->msg_control = NULL;
164 smb_msg->msg_controllen = 0;
165 if (server->noblocksnd)
166 smb_msg->msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL;
168 smb_msg->msg_flags = MSG_NOSIGNAL;
170 while (msg_data_left(smb_msg)) {
172 * If blocking send, we try 3 times, since each can block
173 * for 5 seconds. For nonblocking we have to try more
174 * but wait increasing amounts of time allowing time for
175 * socket to clear. The overall time we wait in either
176 * case to send on the socket is about 15 seconds.
177 * Similarly we wait for 15 seconds for a response from
178 * the server in SendReceive[2] for the server to send
179 * a response back for most types of requests (except
180 * SMB Write past end of file which can be slow, and
181 * blocking lock operations). NFS waits slightly longer
182 * than CIFS, but this can make it take longer for
183 * nonresponsive servers to be detected and 15 seconds
184 * is more than enough time for modern networks to
185 * send a packet. In most cases if we fail to send
186 * after the retries we will kill the socket and
187 * reconnect which may clear the network problem.
189 rc = sock_sendmsg(ssocket, smb_msg);
193 (!server->noblocksnd && (retries > 2))) {
194 cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
198 msleep(1 << retries);
206 /* should never happen, letting socket clear before
207 retrying is our only obvious option here */
208 cifs_dbg(VFS, "tcp sent no data\n");
213 /* send was at least partially successful */
215 retries = 0; /* in case we get ENOSPC on the next send */
221 smb_rqst_len(struct TCP_Server_Info *server, struct smb_rqst *rqst)
226 unsigned long buflen = 0;
228 if (server->vals->header_preamble_size == 0 &&
229 rqst->rq_nvec >= 2 && rqst->rq_iov[0].iov_len == 4) {
230 iov = &rqst->rq_iov[1];
231 nvec = rqst->rq_nvec - 1;
234 nvec = rqst->rq_nvec;
237 /* total up iov array first */
238 for (i = 0; i < nvec; i++)
239 buflen += iov[i].iov_len;
242 * Add in the page array if there is one. The caller needs to make
243 * sure rq_offset and rq_tailsz are set correctly. If a buffer of
244 * multiple pages ends at page boundary, rq_tailsz needs to be set to
247 if (rqst->rq_npages) {
248 if (rqst->rq_npages == 1)
249 buflen += rqst->rq_tailsz;
252 * If there is more than one page, calculate the
253 * buffer length based on rq_offset and rq_tailsz
255 buflen += rqst->rq_pagesz * (rqst->rq_npages - 1) -
257 buflen += rqst->rq_tailsz;
265 __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
266 struct smb_rqst *rqst)
271 unsigned int send_length = 0;
273 size_t total_len = 0, sent, size;
274 struct socket *ssocket = server->ssocket;
275 struct msghdr smb_msg;
277 __be32 rfc1002_marker;
279 if (cifs_rdma_enabled(server) && server->smbd_conn) {
280 rc = smbd_send(server, rqst);
286 /* cork the socket */
287 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
288 (char *)&val, sizeof(val));
290 for (j = 0; j < num_rqst; j++)
291 send_length += smb_rqst_len(server, &rqst[j]);
292 rfc1002_marker = cpu_to_be32(send_length);
294 /* Generate a rfc1002 marker for SMB2+ */
295 if (server->vals->header_preamble_size == 0) {
297 .iov_base = &rfc1002_marker,
300 iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC, &hiov,
302 rc = smb_send_kvec(server, &smb_msg, &sent);
310 cifs_dbg(FYI, "Sending smb: smb_len=%u\n", send_length);
312 for (j = 0; j < num_rqst; j++) {
313 iov = rqst[j].rq_iov;
314 n_vec = rqst[j].rq_nvec;
317 for (i = 0; i < n_vec; i++) {
318 dump_smb(iov[i].iov_base, iov[i].iov_len);
319 size += iov[i].iov_len;
322 iov_iter_kvec(&smb_msg.msg_iter, WRITE | ITER_KVEC,
325 rc = smb_send_kvec(server, &smb_msg, &sent);
331 /* now walk the page array and send each page in it */
332 for (i = 0; i < rqst[j].rq_npages; i++) {
335 bvec.bv_page = rqst[j].rq_pages[i];
336 rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
339 iov_iter_bvec(&smb_msg.msg_iter, WRITE | ITER_BVEC,
340 &bvec, 1, bvec.bv_len);
341 rc = smb_send_kvec(server, &smb_msg, &sent);
352 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
353 (char *)&val, sizeof(val));
355 if ((total_len > 0) && (total_len != send_length)) {
356 cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
357 send_length, total_len);
359 * If we have only sent part of an SMB then the next SMB could
360 * be taken as the remainder of this one. We need to kill the
361 * socket so the server throws away the partial SMB
363 server->tcpStatus = CifsNeedReconnect;
366 if (rc < 0 && rc != -EINTR)
367 cifs_dbg(VFS, "Error %d sending data on socket to server\n",
376 smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst, int flags)
378 struct smb_rqst cur_rqst;
381 if (!(flags & CIFS_TRANSFORM_REQ))
382 return __smb_send_rqst(server, 1, rqst);
384 if (!server->ops->init_transform_rq ||
385 !server->ops->free_transform_rq) {
386 cifs_dbg(VFS, "Encryption requested but transform callbacks are missed\n");
390 rc = server->ops->init_transform_rq(server, &cur_rqst, rqst);
394 rc = __smb_send_rqst(server, 1, &cur_rqst);
395 server->ops->free_transform_rq(&cur_rqst);
400 smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
401 unsigned int smb_buf_length)
404 struct smb_rqst rqst = { .rq_iov = iov,
407 iov[0].iov_base = smb_buffer;
409 iov[1].iov_base = (char *)smb_buffer + 4;
410 iov[1].iov_len = smb_buf_length;
412 return __smb_send_rqst(server, 1, &rqst);
416 wait_for_free_credits(struct TCP_Server_Info *server, const int timeout,
421 spin_lock(&server->req_lock);
422 if (timeout == CIFS_ASYNC_OP) {
423 /* oplock breaks must not be held up */
426 spin_unlock(&server->req_lock);
432 spin_unlock(&server->req_lock);
433 cifs_num_waiters_inc(server);
434 rc = wait_event_killable(server->request_q,
435 has_credits(server, credits));
436 cifs_num_waiters_dec(server);
439 spin_lock(&server->req_lock);
441 if (server->tcpStatus == CifsExiting) {
442 spin_unlock(&server->req_lock);
447 * Can not count locking commands against total
448 * as they are allowed to block on server.
451 /* update # of requests on the wire to server */
452 if (timeout != CIFS_BLOCKING_OP) {
456 spin_unlock(&server->req_lock);
464 wait_for_free_request(struct TCP_Server_Info *server, const int timeout,
469 val = server->ops->get_credits_field(server, optype);
470 /* Since an echo is already inflight, no need to wait to send another */
471 if (*val <= 0 && optype == CIFS_ECHO_OP)
473 return wait_for_free_credits(server, timeout, val);
477 cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
478 unsigned int *num, unsigned int *credits)
485 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
486 struct mid_q_entry **ppmidQ)
488 if (ses->server->tcpStatus == CifsExiting) {
492 if (ses->server->tcpStatus == CifsNeedReconnect) {
493 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
497 if (ses->status == CifsNew) {
498 if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
499 (in_buf->Command != SMB_COM_NEGOTIATE))
501 /* else ok - we are setting up session */
504 if (ses->status == CifsExiting) {
505 /* check if SMB session is bad because we are setting it up */
506 if (in_buf->Command != SMB_COM_LOGOFF_ANDX)
508 /* else ok - we are shutting down session */
511 *ppmidQ = AllocMidQEntry(in_buf, ses->server);
514 spin_lock(&GlobalMid_Lock);
515 list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q);
516 spin_unlock(&GlobalMid_Lock);
521 wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
525 error = wait_event_freezekillable_unsafe(server->response_q,
526 midQ->mid_state != MID_REQUEST_SUBMITTED);
534 cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
537 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
538 struct mid_q_entry *mid;
540 if (rqst->rq_iov[0].iov_len != 4 ||
541 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
542 return ERR_PTR(-EIO);
544 /* enable signing if server requires it */
546 hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
548 mid = AllocMidQEntry(hdr, server);
550 return ERR_PTR(-ENOMEM);
552 rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
554 DeleteMidQEntry(mid);
562 * Send a SMB request and set the callback function in the mid to handle
563 * the result. Caller is responsible for dealing with timeouts.
566 cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
567 mid_receive_t *receive, mid_callback_t *callback,
568 mid_handle_t *handle, void *cbdata, const int flags)
570 int rc, timeout, optype;
571 struct mid_q_entry *mid;
572 unsigned int credits = 0;
574 timeout = flags & CIFS_TIMEOUT_MASK;
575 optype = flags & CIFS_OP_MASK;
577 if ((flags & CIFS_HAS_CREDITS) == 0) {
578 rc = wait_for_free_request(server, timeout, optype);
584 mutex_lock(&server->srv_mutex);
585 mid = server->ops->setup_async_request(server, rqst);
587 mutex_unlock(&server->srv_mutex);
588 add_credits_and_wake_if(server, credits, optype);
592 mid->receive = receive;
593 mid->callback = callback;
594 mid->callback_data = cbdata;
595 mid->handle = handle;
596 mid->mid_state = MID_REQUEST_SUBMITTED;
598 /* put it on the pending_mid_q */
599 spin_lock(&GlobalMid_Lock);
600 list_add_tail(&mid->qhead, &server->pending_mid_q);
601 spin_unlock(&GlobalMid_Lock);
604 * Need to store the time in mid before calling I/O. For call_async,
605 * I/O response may come back and free the mid entry on another thread.
607 cifs_save_when_sent(mid);
608 cifs_in_send_inc(server);
609 rc = smb_send_rqst(server, rqst, flags);
610 cifs_in_send_dec(server);
613 server->sequence_number -= 2;
614 cifs_delete_mid(mid);
617 mutex_unlock(&server->srv_mutex);
622 add_credits_and_wake_if(server, credits, optype);
628 * Send an SMB Request. No response info (other than return code)
629 * needs to be parsed.
631 * flags indicate the type of request buffer and how long to wait
632 * and whether to log NT STATUS code (error) before mapping it to POSIX error
636 SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
637 char *in_buf, int flags)
644 iov[0].iov_base = in_buf;
645 iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
646 flags |= CIFS_NO_RESP;
647 rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
648 cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
654 cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
658 cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n",
659 __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state);
661 spin_lock(&GlobalMid_Lock);
662 switch (mid->mid_state) {
663 case MID_RESPONSE_RECEIVED:
664 spin_unlock(&GlobalMid_Lock);
666 case MID_RETRY_NEEDED:
669 case MID_RESPONSE_MALFORMED:
676 list_del_init(&mid->qhead);
677 cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
678 __func__, mid->mid, mid->mid_state);
681 spin_unlock(&GlobalMid_Lock);
683 DeleteMidQEntry(mid);
688 send_cancel(struct TCP_Server_Info *server, struct smb_rqst *rqst,
689 struct mid_q_entry *mid)
691 return server->ops->send_cancel ?
692 server->ops->send_cancel(server, rqst, mid) : 0;
696 cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
699 unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
701 dump_smb(mid->resp_buf, min_t(u32, 92, len));
703 /* convert the length into a more usable form */
707 struct smb_rqst rqst = { .rq_iov = iov,
710 iov[0].iov_base = mid->resp_buf;
712 iov[1].iov_base = (char *)mid->resp_buf + 4;
713 iov[1].iov_len = len - 4;
714 /* FIXME: add code to kill session */
715 rc = cifs_verify_signature(&rqst, server,
716 mid->sequence_number);
718 cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
722 /* BB special case reconnect tid and uid here? */
723 return map_smb_to_linux_error(mid->resp_buf, log_error);
727 cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
730 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
731 struct mid_q_entry *mid;
733 if (rqst->rq_iov[0].iov_len != 4 ||
734 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
735 return ERR_PTR(-EIO);
737 rc = allocate_mid(ses, hdr, &mid);
740 rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
742 cifs_delete_mid(mid);
749 cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
750 struct smb_rqst *rqst, int *resp_buf_type, const int flags,
751 struct kvec *resp_iov)
755 struct mid_q_entry *midQ;
756 unsigned int credits = 1;
759 timeout = flags & CIFS_TIMEOUT_MASK;
760 optype = flags & CIFS_OP_MASK;
762 *resp_buf_type = CIFS_NO_BUFFER; /* no response buf yet */
764 if ((ses == NULL) || (ses->server == NULL)) {
765 cifs_dbg(VFS, "Null session\n");
769 if (ses->server->tcpStatus == CifsExiting)
773 * Ensure that we do not send more than 50 overlapping requests
774 * to the same server. We may make this configurable later or
777 rc = wait_for_free_request(ses->server, timeout, optype);
782 * Make sure that we sign in the same order that we send on this socket
783 * and avoid races inside tcp sendmsg code that could cause corruption
787 mutex_lock(&ses->server->srv_mutex);
789 midQ = ses->server->ops->setup_request(ses, rqst);
791 mutex_unlock(&ses->server->srv_mutex);
792 /* Update # of requests on wire to server */
793 add_credits(ses->server, 1, optype);
794 return PTR_ERR(midQ);
797 midQ->mid_state = MID_REQUEST_SUBMITTED;
798 cifs_in_send_inc(ses->server);
799 rc = smb_send_rqst(ses->server, rqst, flags);
800 cifs_in_send_dec(ses->server);
801 cifs_save_when_sent(midQ);
804 ses->server->sequence_number -= 2;
805 mutex_unlock(&ses->server->srv_mutex);
810 #ifdef CONFIG_CIFS_SMB311
811 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP))
812 smb311_update_preauth_hash(ses, rqst->rq_iov,
816 if (timeout == CIFS_ASYNC_OP)
819 rc = wait_for_response(ses->server, midQ);
821 cifs_dbg(FYI, "Cancelling wait for mid %llu\n", midQ->mid);
822 send_cancel(ses->server, rqst, midQ);
823 spin_lock(&GlobalMid_Lock);
824 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
825 midQ->mid_flags |= MID_WAIT_CANCELLED;
826 midQ->callback = DeleteMidQEntry;
827 spin_unlock(&GlobalMid_Lock);
828 add_credits(ses->server, 1, optype);
831 spin_unlock(&GlobalMid_Lock);
834 rc = cifs_sync_mid_result(midQ, ses->server);
836 add_credits(ses->server, 1, optype);
840 if (!midQ->resp_buf || midQ->mid_state != MID_RESPONSE_RECEIVED) {
842 cifs_dbg(FYI, "Bad MID state?\n");
846 buf = (char *)midQ->resp_buf;
847 resp_iov->iov_base = buf;
848 resp_iov->iov_len = midQ->resp_buf_size +
849 ses->server->vals->header_preamble_size;
851 *resp_buf_type = CIFS_LARGE_BUFFER;
853 *resp_buf_type = CIFS_SMALL_BUFFER;
855 #ifdef CONFIG_CIFS_SMB311
856 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {
858 .iov_base = resp_iov->iov_base,
859 .iov_len = resp_iov->iov_len
861 smb311_update_preauth_hash(ses, &iov, 1);
865 credits = ses->server->ops->get_credits(midQ);
867 rc = ses->server->ops->check_receive(midQ, ses->server,
868 flags & CIFS_LOG_ERROR);
870 /* mark it so buf will not be freed by cifs_delete_mid */
871 if ((flags & CIFS_NO_RESP) == 0)
872 midQ->resp_buf = NULL;
874 cifs_delete_mid(midQ);
875 add_credits(ses->server, credits, optype);
881 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
882 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
883 const int flags, struct kvec *resp_iov)
885 struct smb_rqst rqst;
886 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
889 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
890 new_iov = kmalloc_array(n_vec + 1, sizeof(struct kvec),
893 /* otherwise cifs_send_recv below sets resp_buf_type */
894 *resp_buf_type = CIFS_NO_BUFFER;
900 /* 1st iov is a RFC1001 length followed by the rest of the packet */
901 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
903 new_iov[0].iov_base = new_iov[1].iov_base;
904 new_iov[0].iov_len = 4;
905 new_iov[1].iov_base += 4;
906 new_iov[1].iov_len -= 4;
908 memset(&rqst, 0, sizeof(struct smb_rqst));
909 rqst.rq_iov = new_iov;
910 rqst.rq_nvec = n_vec + 1;
912 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
913 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
919 SendReceive(const unsigned int xid, struct cifs_ses *ses,
920 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
921 int *pbytes_returned, const int timeout)
924 struct mid_q_entry *midQ;
925 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
926 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
927 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
930 cifs_dbg(VFS, "Null smb session\n");
933 if (ses->server == NULL) {
934 cifs_dbg(VFS, "Null tcp session\n");
938 if (ses->server->tcpStatus == CifsExiting)
941 /* Ensure that we do not send more than 50 overlapping requests
942 to the same server. We may make this configurable later or
945 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
946 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
951 rc = wait_for_free_request(ses->server, timeout, 0);
955 /* make sure that we sign in the same order that we send on this socket
956 and avoid races inside tcp sendmsg code that could cause corruption
959 mutex_lock(&ses->server->srv_mutex);
961 rc = allocate_mid(ses, in_buf, &midQ);
963 mutex_unlock(&ses->server->srv_mutex);
964 /* Update # of requests on wire to server */
965 add_credits(ses->server, 1, 0);
969 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
971 mutex_unlock(&ses->server->srv_mutex);
975 midQ->mid_state = MID_REQUEST_SUBMITTED;
977 cifs_in_send_inc(ses->server);
978 rc = smb_send(ses->server, in_buf, len);
979 cifs_in_send_dec(ses->server);
980 cifs_save_when_sent(midQ);
983 ses->server->sequence_number -= 2;
985 mutex_unlock(&ses->server->srv_mutex);
990 if (timeout == CIFS_ASYNC_OP)
993 rc = wait_for_response(ses->server, midQ);
995 send_cancel(ses->server, &rqst, midQ);
996 spin_lock(&GlobalMid_Lock);
997 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
998 /* no longer considered to be "in-flight" */
999 midQ->callback = DeleteMidQEntry;
1000 spin_unlock(&GlobalMid_Lock);
1001 add_credits(ses->server, 1, 0);
1004 spin_unlock(&GlobalMid_Lock);
1007 rc = cifs_sync_mid_result(midQ, ses->server);
1009 add_credits(ses->server, 1, 0);
1013 if (!midQ->resp_buf || !out_buf ||
1014 midQ->mid_state != MID_RESPONSE_RECEIVED) {
1016 cifs_dbg(VFS, "Bad MID state?\n");
1020 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1021 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1022 rc = cifs_check_receive(midQ, ses->server, 0);
1024 cifs_delete_mid(midQ);
1025 add_credits(ses->server, 1, 0);
1030 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
1031 blocking lock to return. */
1034 send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
1035 struct smb_hdr *in_buf,
1036 struct smb_hdr *out_buf)
1039 struct cifs_ses *ses = tcon->ses;
1040 LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
1042 /* We just modify the current in_buf to change
1043 the type of lock from LOCKING_ANDX_SHARED_LOCK
1044 or LOCKING_ANDX_EXCLUSIVE_LOCK to
1045 LOCKING_ANDX_CANCEL_LOCK. */
1047 pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
1049 pSMB->hdr.Mid = get_next_mid(ses->server);
1051 return SendReceive(xid, ses, in_buf, out_buf,
1052 &bytes_returned, 0);
1056 SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
1057 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1058 int *pbytes_returned)
1062 struct mid_q_entry *midQ;
1063 struct cifs_ses *ses;
1064 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1065 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1066 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1068 if (tcon == NULL || tcon->ses == NULL) {
1069 cifs_dbg(VFS, "Null smb session\n");
1074 if (ses->server == NULL) {
1075 cifs_dbg(VFS, "Null tcp session\n");
1079 if (ses->server->tcpStatus == CifsExiting)
1082 /* Ensure that we do not send more than 50 overlapping requests
1083 to the same server. We may make this configurable later or
1086 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1087 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1092 rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0);
1096 /* make sure that we sign in the same order that we send on this socket
1097 and avoid races inside tcp sendmsg code that could cause corruption
1100 mutex_lock(&ses->server->srv_mutex);
1102 rc = allocate_mid(ses, in_buf, &midQ);
1104 mutex_unlock(&ses->server->srv_mutex);
1108 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
1110 cifs_delete_mid(midQ);
1111 mutex_unlock(&ses->server->srv_mutex);
1115 midQ->mid_state = MID_REQUEST_SUBMITTED;
1116 cifs_in_send_inc(ses->server);
1117 rc = smb_send(ses->server, in_buf, len);
1118 cifs_in_send_dec(ses->server);
1119 cifs_save_when_sent(midQ);
1122 ses->server->sequence_number -= 2;
1124 mutex_unlock(&ses->server->srv_mutex);
1127 cifs_delete_mid(midQ);
1131 /* Wait for a reply - allow signals to interrupt. */
1132 rc = wait_event_interruptible(ses->server->response_q,
1133 (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
1134 ((ses->server->tcpStatus != CifsGood) &&
1135 (ses->server->tcpStatus != CifsNew)));
1137 /* Were we interrupted by a signal ? */
1138 if ((rc == -ERESTARTSYS) &&
1139 (midQ->mid_state == MID_REQUEST_SUBMITTED) &&
1140 ((ses->server->tcpStatus == CifsGood) ||
1141 (ses->server->tcpStatus == CifsNew))) {
1143 if (in_buf->Command == SMB_COM_TRANSACTION2) {
1144 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1145 blocking lock to return. */
1146 rc = send_cancel(ses->server, &rqst, midQ);
1148 cifs_delete_mid(midQ);
1152 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1153 to cause the blocking lock to return. */
1155 rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
1157 /* If we get -ENOLCK back the lock may have
1158 already been removed. Don't exit in this case. */
1159 if (rc && rc != -ENOLCK) {
1160 cifs_delete_mid(midQ);
1165 rc = wait_for_response(ses->server, midQ);
1167 send_cancel(ses->server, &rqst, midQ);
1168 spin_lock(&GlobalMid_Lock);
1169 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1170 /* no longer considered to be "in-flight" */
1171 midQ->callback = DeleteMidQEntry;
1172 spin_unlock(&GlobalMid_Lock);
1175 spin_unlock(&GlobalMid_Lock);
1178 /* We got the response - restart system call. */
1182 rc = cifs_sync_mid_result(midQ, ses->server);
1186 /* rcvd frame is ok */
1187 if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) {
1189 cifs_dbg(VFS, "Bad MID state?\n");
1193 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1194 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1195 rc = cifs_check_receive(midQ, ses->server, 0);
1197 cifs_delete_mid(midQ);
1198 if (rstart && rc == -EACCES)
1199 return -ERESTARTSYS;