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>
36 #include <linux/sched/signal.h>
39 #include "cifsproto.h"
40 #include "cifs_debug.h"
41 #include "smb2proto.h"
42 #include "smbdirect.h"
44 /* Max number of iovectors we can use off the stack when sending requests. */
45 #define CIFS_MAX_IOV_SIZE 8
48 cifs_wake_up_task(struct mid_q_entry *mid)
50 wake_up_process(mid->callback_data);
54 AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
56 struct mid_q_entry *temp;
59 cifs_dbg(VFS, "Null TCP session in AllocMidQEntry\n");
63 temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
64 memset(temp, 0, sizeof(struct mid_q_entry));
65 kref_init(&temp->refcount);
66 temp->mid = get_mid(smb_buffer);
67 temp->pid = current->pid;
68 temp->command = cpu_to_le16(smb_buffer->Command);
69 cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
70 /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
71 /* when mid allocated can be before when sent */
72 temp->when_alloc = jiffies;
73 temp->server = server;
76 * The default is for the mid to be synchronous, so the
77 * default callback just wakes up the current task.
79 temp->callback = cifs_wake_up_task;
80 temp->callback_data = current;
82 atomic_inc(&midCount);
83 temp->mid_state = MID_REQUEST_ALLOCATED;
87 static void _cifs_mid_q_entry_release(struct kref *refcount)
89 struct mid_q_entry *mid = container_of(refcount, struct mid_q_entry,
92 mempool_free(mid, cifs_mid_poolp);
95 void cifs_mid_q_entry_release(struct mid_q_entry *midEntry)
97 spin_lock(&GlobalMid_Lock);
98 kref_put(&midEntry->refcount, _cifs_mid_q_entry_release);
99 spin_unlock(&GlobalMid_Lock);
103 DeleteMidQEntry(struct mid_q_entry *midEntry)
105 #ifdef CONFIG_CIFS_STATS2
106 __le16 command = midEntry->server->vals->lock_cmd;
107 __u16 smb_cmd = le16_to_cpu(midEntry->command);
109 unsigned long roundtrip_time;
110 struct TCP_Server_Info *server = midEntry->server;
112 midEntry->mid_state = MID_FREE;
113 atomic_dec(&midCount);
114 if (midEntry->large_buf)
115 cifs_buf_release(midEntry->resp_buf);
117 cifs_small_buf_release(midEntry->resp_buf);
118 #ifdef CONFIG_CIFS_STATS2
120 if (now < midEntry->when_alloc)
121 cifs_dbg(VFS, "invalid mid allocation time\n");
122 roundtrip_time = now - midEntry->when_alloc;
124 if (smb_cmd < NUMBER_OF_SMB2_COMMANDS) {
125 if (atomic_read(&server->num_cmds[smb_cmd]) == 0) {
126 server->slowest_cmd[smb_cmd] = roundtrip_time;
127 server->fastest_cmd[smb_cmd] = roundtrip_time;
129 if (server->slowest_cmd[smb_cmd] < roundtrip_time)
130 server->slowest_cmd[smb_cmd] = roundtrip_time;
131 else if (server->fastest_cmd[smb_cmd] > roundtrip_time)
132 server->fastest_cmd[smb_cmd] = roundtrip_time;
134 cifs_stats_inc(&server->num_cmds[smb_cmd]);
135 server->time_per_cmd[smb_cmd] += roundtrip_time;
138 * commands taking longer than one second (default) can be indications
139 * that something is wrong, unless it is quite a slow link or a very
140 * busy server. Note that this calc is unlikely or impossible to wrap
141 * as long as slow_rsp_threshold is not set way above recommended max
142 * value (32767 ie 9 hours) and is generally harmless even if wrong
143 * since only affects debug counters - so leaving the calc as simple
144 * comparison rather than doing multiple conversions and overflow
147 if ((slow_rsp_threshold != 0) &&
148 time_after(now, midEntry->when_alloc + (slow_rsp_threshold * HZ)) &&
149 (midEntry->command != command)) {
151 * smb2slowcmd[NUMBER_OF_SMB2_COMMANDS] counts by command
152 * NB: le16_to_cpu returns unsigned so can not be negative below
154 if (smb_cmd < NUMBER_OF_SMB2_COMMANDS)
155 cifs_stats_inc(&server->smb2slowcmd[smb_cmd]);
157 trace_smb3_slow_rsp(smb_cmd, midEntry->mid, midEntry->pid,
158 midEntry->when_sent, midEntry->when_received);
159 if (cifsFYI & CIFS_TIMER) {
160 pr_debug(" CIFS slow rsp: cmd %d mid %llu",
161 midEntry->command, midEntry->mid);
162 cifs_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
163 now - midEntry->when_alloc,
164 now - midEntry->when_sent,
165 now - midEntry->when_received);
169 cifs_mid_q_entry_release(midEntry);
173 cifs_delete_mid(struct mid_q_entry *mid)
175 spin_lock(&GlobalMid_Lock);
176 list_del_init(&mid->qhead);
177 mid->mid_flags |= MID_DELETED;
178 spin_unlock(&GlobalMid_Lock);
180 DeleteMidQEntry(mid);
184 * smb_send_kvec - send an array of kvecs to the server
185 * @server: Server to send the data to
186 * @smb_msg: Message to send
187 * @sent: amount of data sent on socket is stored here
189 * Our basic "send data to server" function. Should be called with srv_mutex
190 * held. The caller is responsible for handling the results.
193 smb_send_kvec(struct TCP_Server_Info *server, struct msghdr *smb_msg,
198 struct socket *ssocket = server->ssocket;
202 smb_msg->msg_name = (struct sockaddr *) &server->dstaddr;
203 smb_msg->msg_namelen = sizeof(struct sockaddr);
204 smb_msg->msg_control = NULL;
205 smb_msg->msg_controllen = 0;
206 if (server->noblocksnd)
207 smb_msg->msg_flags = MSG_DONTWAIT + MSG_NOSIGNAL;
209 smb_msg->msg_flags = MSG_NOSIGNAL;
211 while (msg_data_left(smb_msg)) {
213 * If blocking send, we try 3 times, since each can block
214 * for 5 seconds. For nonblocking we have to try more
215 * but wait increasing amounts of time allowing time for
216 * socket to clear. The overall time we wait in either
217 * case to send on the socket is about 15 seconds.
218 * Similarly we wait for 15 seconds for a response from
219 * the server in SendReceive[2] for the server to send
220 * a response back for most types of requests (except
221 * SMB Write past end of file which can be slow, and
222 * blocking lock operations). NFS waits slightly longer
223 * than CIFS, but this can make it take longer for
224 * nonresponsive servers to be detected and 15 seconds
225 * is more than enough time for modern networks to
226 * send a packet. In most cases if we fail to send
227 * after the retries we will kill the socket and
228 * reconnect which may clear the network problem.
230 rc = sock_sendmsg(ssocket, smb_msg);
234 (!server->noblocksnd && (retries > 2))) {
235 cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
239 msleep(1 << retries);
247 /* should never happen, letting socket clear before
248 retrying is our only obvious option here */
249 cifs_dbg(VFS, "tcp sent no data\n");
254 /* send was at least partially successful */
256 retries = 0; /* in case we get ENOSPC on the next send */
262 smb_rqst_len(struct TCP_Server_Info *server, struct smb_rqst *rqst)
267 unsigned long buflen = 0;
269 if (server->vals->header_preamble_size == 0 &&
270 rqst->rq_nvec >= 2 && rqst->rq_iov[0].iov_len == 4) {
271 iov = &rqst->rq_iov[1];
272 nvec = rqst->rq_nvec - 1;
275 nvec = rqst->rq_nvec;
278 /* total up iov array first */
279 for (i = 0; i < nvec; i++)
280 buflen += iov[i].iov_len;
283 * Add in the page array if there is one. The caller needs to make
284 * sure rq_offset and rq_tailsz are set correctly. If a buffer of
285 * multiple pages ends at page boundary, rq_tailsz needs to be set to
288 if (rqst->rq_npages) {
289 if (rqst->rq_npages == 1)
290 buflen += rqst->rq_tailsz;
293 * If there is more than one page, calculate the
294 * buffer length based on rq_offset and rq_tailsz
296 buflen += rqst->rq_pagesz * (rqst->rq_npages - 1) -
298 buflen += rqst->rq_tailsz;
306 __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
307 struct smb_rqst *rqst)
312 unsigned int send_length = 0;
314 sigset_t mask, oldmask;
315 size_t total_len = 0, sent, size;
316 struct socket *ssocket = server->ssocket;
317 struct msghdr smb_msg;
319 __be32 rfc1002_marker;
321 if (cifs_rdma_enabled(server) && server->smbd_conn) {
322 rc = smbd_send(server, num_rqst, rqst);
329 if (signal_pending(current)) {
330 cifs_dbg(FYI, "signal is pending before sending any data\n");
334 /* cork the socket */
335 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
336 (char *)&val, sizeof(val));
338 for (j = 0; j < num_rqst; j++)
339 send_length += smb_rqst_len(server, &rqst[j]);
340 rfc1002_marker = cpu_to_be32(send_length);
343 * We should not allow signals to interrupt the network send because
344 * any partial send will cause session reconnects thus increasing
345 * latency of system calls and overload a server with unnecessary
350 sigprocmask(SIG_BLOCK, &mask, &oldmask);
352 /* Generate a rfc1002 marker for SMB2+ */
353 if (server->vals->header_preamble_size == 0) {
355 .iov_base = &rfc1002_marker,
358 iov_iter_kvec(&smb_msg.msg_iter, WRITE, &hiov, 1, 4);
359 rc = smb_send_kvec(server, &smb_msg, &sent);
367 cifs_dbg(FYI, "Sending smb: smb_len=%u\n", send_length);
369 for (j = 0; j < num_rqst; j++) {
370 iov = rqst[j].rq_iov;
371 n_vec = rqst[j].rq_nvec;
374 for (i = 0; i < n_vec; i++) {
375 dump_smb(iov[i].iov_base, iov[i].iov_len);
376 size += iov[i].iov_len;
379 iov_iter_kvec(&smb_msg.msg_iter, WRITE, iov, n_vec, size);
381 rc = smb_send_kvec(server, &smb_msg, &sent);
387 /* now walk the page array and send each page in it */
388 for (i = 0; i < rqst[j].rq_npages; i++) {
391 bvec.bv_page = rqst[j].rq_pages[i];
392 rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
395 iov_iter_bvec(&smb_msg.msg_iter, WRITE,
396 &bvec, 1, bvec.bv_len);
397 rc = smb_send_kvec(server, &smb_msg, &sent);
406 sigprocmask(SIG_SETMASK, &oldmask, NULL);
409 * If signal is pending but we have already sent the whole packet to
410 * the server we need to return success status to allow a corresponding
411 * mid entry to be kept in the pending requests queue thus allowing
412 * to handle responses from the server by the client.
414 * If only part of the packet has been sent there is no need to hide
415 * interrupt because the session will be reconnected anyway, so there
416 * won't be any response from the server to handle.
419 if (signal_pending(current) && (total_len != send_length)) {
420 cifs_dbg(FYI, "signal is pending after attempt to send\n");
426 kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
427 (char *)&val, sizeof(val));
429 if ((total_len > 0) && (total_len != send_length)) {
430 cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
431 send_length, total_len);
433 * If we have only sent part of an SMB then the next SMB could
434 * be taken as the remainder of this one. We need to kill the
435 * socket so the server throws away the partial SMB
437 server->tcpStatus = CifsNeedReconnect;
438 trace_smb3_partial_send_reconnect(server->CurrentMid,
442 if (rc < 0 && rc != -EINTR)
443 cifs_dbg(VFS, "Error %d sending data on socket to server\n",
452 smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
453 struct smb_rqst *rqst, int flags)
456 struct smb2_transform_hdr tr_hdr;
457 struct smb_rqst cur_rqst[MAX_COMPOUND];
460 if (!(flags & CIFS_TRANSFORM_REQ))
461 return __smb_send_rqst(server, num_rqst, rqst);
463 if (num_rqst > MAX_COMPOUND - 1)
466 memset(&cur_rqst[0], 0, sizeof(cur_rqst));
467 memset(&iov, 0, sizeof(iov));
468 memset(&tr_hdr, 0, sizeof(tr_hdr));
470 iov.iov_base = &tr_hdr;
471 iov.iov_len = sizeof(tr_hdr);
472 cur_rqst[0].rq_iov = &iov;
473 cur_rqst[0].rq_nvec = 1;
475 if (!server->ops->init_transform_rq) {
476 cifs_dbg(VFS, "Encryption requested but transform callback "
481 rc = server->ops->init_transform_rq(server, num_rqst + 1,
486 rc = __smb_send_rqst(server, num_rqst + 1, &cur_rqst[0]);
487 smb3_free_compound_rqst(num_rqst, &cur_rqst[1]);
492 smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
493 unsigned int smb_buf_length)
496 struct smb_rqst rqst = { .rq_iov = iov,
499 iov[0].iov_base = smb_buffer;
501 iov[1].iov_base = (char *)smb_buffer + 4;
502 iov[1].iov_len = smb_buf_length;
504 return __smb_send_rqst(server, 1, &rqst);
508 wait_for_free_credits(struct TCP_Server_Info *server, const int num_credits,
509 const int timeout, const int flags,
510 unsigned int *instance)
518 t = MAX_JIFFY_OFFSET;
520 t = msecs_to_jiffies(timeout);
522 optype = flags & CIFS_OP_MASK;
526 credits = server->ops->get_credits_field(server, optype);
527 /* Since an echo is already inflight, no need to wait to send another */
528 if (*credits <= 0 && optype == CIFS_ECHO_OP)
531 spin_lock(&server->req_lock);
532 if ((flags & CIFS_TIMEOUT_MASK) == CIFS_NON_BLOCKING) {
533 /* oplock breaks must not be held up */
536 *instance = server->reconnect_instance;
537 spin_unlock(&server->req_lock);
542 if (*credits < num_credits) {
543 spin_unlock(&server->req_lock);
544 cifs_num_waiters_inc(server);
545 rc = wait_event_killable_timeout(server->request_q,
546 has_credits(server, credits, num_credits), t);
547 cifs_num_waiters_dec(server);
549 trace_smb3_credit_timeout(server->CurrentMid,
550 server->hostname, num_credits);
551 cifs_dbg(VFS, "wait timed out after %d ms\n",
555 if (rc == -ERESTARTSYS)
557 spin_lock(&server->req_lock);
559 if (server->tcpStatus == CifsExiting) {
560 spin_unlock(&server->req_lock);
565 * For normal commands, reserve the last MAX_COMPOUND
566 * credits to compound requests.
567 * Otherwise these compounds could be permanently
568 * starved for credits by single-credit requests.
570 * To prevent spinning CPU, block this thread until
571 * there are >MAX_COMPOUND credits available.
572 * But only do this is we already have a lot of
573 * credits in flight to avoid triggering this check
574 * for servers that are slow to hand out credits on
577 if (!optype && num_credits == 1 &&
578 server->in_flight > 2 * MAX_COMPOUND &&
579 *credits <= MAX_COMPOUND) {
580 spin_unlock(&server->req_lock);
581 cifs_num_waiters_inc(server);
582 rc = wait_event_killable_timeout(
584 has_credits(server, credits,
587 cifs_num_waiters_dec(server);
589 trace_smb3_credit_timeout(
591 server->hostname, num_credits);
592 cifs_dbg(VFS, "wait timed out after %d ms\n",
596 if (rc == -ERESTARTSYS)
598 spin_lock(&server->req_lock);
603 * Can not count locking commands against total
604 * as they are allowed to block on server.
607 /* update # of requests on the wire to server */
608 if ((flags & CIFS_TIMEOUT_MASK) != CIFS_BLOCKING_OP) {
609 *credits -= num_credits;
610 server->in_flight += num_credits;
611 *instance = server->reconnect_instance;
613 spin_unlock(&server->req_lock);
621 wait_for_free_request(struct TCP_Server_Info *server, const int flags,
622 unsigned int *instance)
624 return wait_for_free_credits(server, 1, -1, flags,
629 wait_for_compound_request(struct TCP_Server_Info *server, int num,
630 const int flags, unsigned int *instance)
634 credits = server->ops->get_credits_field(server, flags & CIFS_OP_MASK);
636 spin_lock(&server->req_lock);
637 if (*credits < num) {
639 * Return immediately if not too many requests in flight since
640 * we will likely be stuck on waiting for credits.
642 if (server->in_flight < num - *credits) {
643 spin_unlock(&server->req_lock);
647 spin_unlock(&server->req_lock);
649 return wait_for_free_credits(server, num, 60000, flags,
654 cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
655 unsigned int *num, struct cifs_credits *credits)
659 credits->instance = server->reconnect_instance;
663 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
664 struct mid_q_entry **ppmidQ)
666 if (ses->server->tcpStatus == CifsExiting) {
670 if (ses->server->tcpStatus == CifsNeedReconnect) {
671 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
675 if (ses->status == CifsNew) {
676 if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
677 (in_buf->Command != SMB_COM_NEGOTIATE))
679 /* else ok - we are setting up session */
682 if (ses->status == CifsExiting) {
683 /* check if SMB session is bad because we are setting it up */
684 if (in_buf->Command != SMB_COM_LOGOFF_ANDX)
686 /* else ok - we are shutting down session */
689 *ppmidQ = AllocMidQEntry(in_buf, ses->server);
692 spin_lock(&GlobalMid_Lock);
693 list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q);
694 spin_unlock(&GlobalMid_Lock);
699 wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
703 error = wait_event_freezekillable_unsafe(server->response_q,
704 midQ->mid_state != MID_REQUEST_SUBMITTED);
712 cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
715 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
716 struct mid_q_entry *mid;
718 if (rqst->rq_iov[0].iov_len != 4 ||
719 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
720 return ERR_PTR(-EIO);
722 /* enable signing if server requires it */
724 hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
726 mid = AllocMidQEntry(hdr, server);
728 return ERR_PTR(-ENOMEM);
730 rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
732 DeleteMidQEntry(mid);
740 * Send a SMB request and set the callback function in the mid to handle
741 * the result. Caller is responsible for dealing with timeouts.
744 cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
745 mid_receive_t *receive, mid_callback_t *callback,
746 mid_handle_t *handle, void *cbdata, const int flags,
747 const struct cifs_credits *exist_credits)
750 struct mid_q_entry *mid;
751 struct cifs_credits credits = { .value = 0, .instance = 0 };
752 unsigned int instance;
755 optype = flags & CIFS_OP_MASK;
757 if ((flags & CIFS_HAS_CREDITS) == 0) {
758 rc = wait_for_free_request(server, flags, &instance);
762 credits.instance = instance;
764 instance = exist_credits->instance;
766 mutex_lock(&server->srv_mutex);
769 * We can't use credits obtained from the previous session to send this
770 * request. Check if there were reconnects after we obtained credits and
771 * return -EAGAIN in such cases to let callers handle it.
773 if (instance != server->reconnect_instance) {
774 mutex_unlock(&server->srv_mutex);
775 add_credits_and_wake_if(server, &credits, optype);
779 mid = server->ops->setup_async_request(server, rqst);
781 mutex_unlock(&server->srv_mutex);
782 add_credits_and_wake_if(server, &credits, optype);
786 mid->receive = receive;
787 mid->callback = callback;
788 mid->callback_data = cbdata;
789 mid->handle = handle;
790 mid->mid_state = MID_REQUEST_SUBMITTED;
792 /* put it on the pending_mid_q */
793 spin_lock(&GlobalMid_Lock);
794 list_add_tail(&mid->qhead, &server->pending_mid_q);
795 spin_unlock(&GlobalMid_Lock);
798 * Need to store the time in mid before calling I/O. For call_async,
799 * I/O response may come back and free the mid entry on another thread.
801 cifs_save_when_sent(mid);
802 cifs_in_send_inc(server);
803 rc = smb_send_rqst(server, 1, rqst, flags);
804 cifs_in_send_dec(server);
807 revert_current_mid(server, mid->credits);
808 server->sequence_number -= 2;
809 cifs_delete_mid(mid);
812 mutex_unlock(&server->srv_mutex);
817 add_credits_and_wake_if(server, &credits, optype);
823 * Send an SMB Request. No response info (other than return code)
824 * needs to be parsed.
826 * flags indicate the type of request buffer and how long to wait
827 * and whether to log NT STATUS code (error) before mapping it to POSIX error
831 SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
832 char *in_buf, int flags)
839 iov[0].iov_base = in_buf;
840 iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
841 flags |= CIFS_NO_RSP_BUF;
842 rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
843 cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
849 cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
853 cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n",
854 __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state);
856 spin_lock(&GlobalMid_Lock);
857 switch (mid->mid_state) {
858 case MID_RESPONSE_RECEIVED:
859 spin_unlock(&GlobalMid_Lock);
861 case MID_RETRY_NEEDED:
864 case MID_RESPONSE_MALFORMED:
871 list_del_init(&mid->qhead);
872 cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
873 __func__, mid->mid, mid->mid_state);
876 spin_unlock(&GlobalMid_Lock);
878 DeleteMidQEntry(mid);
883 send_cancel(struct TCP_Server_Info *server, struct smb_rqst *rqst,
884 struct mid_q_entry *mid)
886 return server->ops->send_cancel ?
887 server->ops->send_cancel(server, rqst, mid) : 0;
891 cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
894 unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
896 dump_smb(mid->resp_buf, min_t(u32, 92, len));
898 /* convert the length into a more usable form */
902 struct smb_rqst rqst = { .rq_iov = iov,
905 iov[0].iov_base = mid->resp_buf;
907 iov[1].iov_base = (char *)mid->resp_buf + 4;
908 iov[1].iov_len = len - 4;
909 /* FIXME: add code to kill session */
910 rc = cifs_verify_signature(&rqst, server,
911 mid->sequence_number);
913 cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
917 /* BB special case reconnect tid and uid here? */
918 return map_smb_to_linux_error(mid->resp_buf, log_error);
922 cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
925 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
926 struct mid_q_entry *mid;
928 if (rqst->rq_iov[0].iov_len != 4 ||
929 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
930 return ERR_PTR(-EIO);
932 rc = allocate_mid(ses, hdr, &mid);
935 rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
937 cifs_delete_mid(mid);
944 cifs_compound_callback(struct mid_q_entry *mid)
946 struct TCP_Server_Info *server = mid->server;
947 struct cifs_credits credits;
949 credits.value = server->ops->get_credits(mid);
950 credits.instance = server->reconnect_instance;
952 add_credits(server, &credits, mid->optype);
956 cifs_compound_last_callback(struct mid_q_entry *mid)
958 cifs_compound_callback(mid);
959 cifs_wake_up_task(mid);
963 cifs_cancelled_callback(struct mid_q_entry *mid)
965 cifs_compound_callback(mid);
966 DeleteMidQEntry(mid);
970 compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
971 const int flags, const int num_rqst, struct smb_rqst *rqst,
972 int *resp_buf_type, struct kvec *resp_iov)
974 int i, j, optype, rc = 0;
975 struct mid_q_entry *midQ[MAX_COMPOUND];
976 bool cancelled_mid[MAX_COMPOUND] = {false};
977 struct cifs_credits credits[MAX_COMPOUND] = {
978 { .value = 0, .instance = 0 }
980 unsigned int instance;
982 struct TCP_Server_Info *server;
984 optype = flags & CIFS_OP_MASK;
986 for (i = 0; i < num_rqst; i++)
987 resp_buf_type[i] = CIFS_NO_BUFFER; /* no response buf yet */
989 if ((ses == NULL) || (ses->server == NULL)) {
990 cifs_dbg(VFS, "Null session\n");
994 server = ses->server;
995 if (server->tcpStatus == CifsExiting)
999 * Wait for all the requests to become available.
1000 * This approach still leaves the possibility to be stuck waiting for
1001 * credits if the server doesn't grant credits to the outstanding
1002 * requests and if the client is completely idle, not generating any
1004 * This can be handled by the eventual session reconnect.
1006 rc = wait_for_compound_request(server, num_rqst, flags,
1011 for (i = 0; i < num_rqst; i++) {
1012 credits[i].value = 1;
1013 credits[i].instance = instance;
1017 * Make sure that we sign in the same order that we send on this socket
1018 * and avoid races inside tcp sendmsg code that could cause corruption
1022 mutex_lock(&server->srv_mutex);
1025 * All the parts of the compound chain belong obtained credits from the
1026 * same session. We can not use credits obtained from the previous
1027 * session to send this request. Check if there were reconnects after
1028 * we obtained credits and return -EAGAIN in such cases to let callers
1031 if (instance != server->reconnect_instance) {
1032 mutex_unlock(&server->srv_mutex);
1033 for (j = 0; j < num_rqst; j++)
1034 add_credits(server, &credits[j], optype);
1038 for (i = 0; i < num_rqst; i++) {
1039 midQ[i] = server->ops->setup_request(ses, &rqst[i]);
1040 if (IS_ERR(midQ[i])) {
1041 revert_current_mid(server, i);
1042 for (j = 0; j < i; j++)
1043 cifs_delete_mid(midQ[j]);
1044 mutex_unlock(&server->srv_mutex);
1046 /* Update # of requests on wire to server */
1047 for (j = 0; j < num_rqst; j++)
1048 add_credits(server, &credits[j], optype);
1049 return PTR_ERR(midQ[i]);
1052 midQ[i]->mid_state = MID_REQUEST_SUBMITTED;
1053 midQ[i]->optype = optype;
1055 * Invoke callback for every part of the compound chain
1056 * to calculate credits properly. Wake up this thread only when
1057 * the last element is received.
1059 if (i < num_rqst - 1)
1060 midQ[i]->callback = cifs_compound_callback;
1062 midQ[i]->callback = cifs_compound_last_callback;
1064 cifs_in_send_inc(server);
1065 rc = smb_send_rqst(server, num_rqst, rqst, flags);
1066 cifs_in_send_dec(server);
1068 for (i = 0; i < num_rqst; i++)
1069 cifs_save_when_sent(midQ[i]);
1072 revert_current_mid(server, num_rqst);
1073 server->sequence_number -= 2;
1076 mutex_unlock(&server->srv_mutex);
1079 * If sending failed for some reason or it is an oplock break that we
1080 * will not receive a response to - return credits back
1082 if (rc < 0 || (flags & CIFS_NO_SRV_RSP)) {
1083 for (i = 0; i < num_rqst; i++)
1084 add_credits(server, &credits[i], optype);
1089 * At this point the request is passed to the network stack - we assume
1090 * that any credits taken from the server structure on the client have
1091 * been spent and we can't return them back. Once we receive responses
1092 * we will collect credits granted by the server in the mid callbacks
1093 * and add those credits to the server structure.
1097 * Compounding is never used during session establish.
1099 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP))
1100 smb311_update_preauth_hash(ses, rqst[0].rq_iov,
1103 for (i = 0; i < num_rqst; i++) {
1104 rc = wait_for_response(server, midQ[i]);
1109 for (; i < num_rqst; i++) {
1110 cifs_dbg(VFS, "Cancelling wait for mid %llu cmd: %d\n",
1111 midQ[i]->mid, le16_to_cpu(midQ[i]->command));
1112 send_cancel(server, &rqst[i], midQ[i]);
1113 spin_lock(&GlobalMid_Lock);
1114 if (midQ[i]->mid_state == MID_REQUEST_SUBMITTED) {
1115 midQ[i]->mid_flags |= MID_WAIT_CANCELLED;
1116 midQ[i]->callback = cifs_cancelled_callback;
1117 cancelled_mid[i] = true;
1118 credits[i].value = 0;
1120 spin_unlock(&GlobalMid_Lock);
1124 for (i = 0; i < num_rqst; i++) {
1128 rc = cifs_sync_mid_result(midQ[i], server);
1130 /* mark this mid as cancelled to not free it below */
1131 cancelled_mid[i] = true;
1135 if (!midQ[i]->resp_buf ||
1136 midQ[i]->mid_state != MID_RESPONSE_RECEIVED) {
1138 cifs_dbg(FYI, "Bad MID state?\n");
1142 buf = (char *)midQ[i]->resp_buf;
1143 resp_iov[i].iov_base = buf;
1144 resp_iov[i].iov_len = midQ[i]->resp_buf_size +
1145 server->vals->header_preamble_size;
1147 if (midQ[i]->large_buf)
1148 resp_buf_type[i] = CIFS_LARGE_BUFFER;
1150 resp_buf_type[i] = CIFS_SMALL_BUFFER;
1152 rc = server->ops->check_receive(midQ[i], server,
1153 flags & CIFS_LOG_ERROR);
1155 /* mark it so buf will not be freed by cifs_delete_mid */
1156 if ((flags & CIFS_NO_RSP_BUF) == 0)
1157 midQ[i]->resp_buf = NULL;
1162 * Compounding is never used during session establish.
1164 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {
1166 .iov_base = resp_iov[0].iov_base,
1167 .iov_len = resp_iov[0].iov_len
1169 smb311_update_preauth_hash(ses, &iov, 1);
1174 * This will dequeue all mids. After this it is important that the
1175 * demultiplex_thread will not process any of these mids any futher.
1176 * This is prevented above by using a noop callback that will not
1177 * wake this thread except for the very last PDU.
1179 for (i = 0; i < num_rqst; i++) {
1180 if (!cancelled_mid[i])
1181 cifs_delete_mid(midQ[i]);
1188 cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
1189 struct smb_rqst *rqst, int *resp_buf_type, const int flags,
1190 struct kvec *resp_iov)
1192 return compound_send_recv(xid, ses, flags, 1, rqst, resp_buf_type,
1197 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
1198 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
1199 const int flags, struct kvec *resp_iov)
1201 struct smb_rqst rqst;
1202 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
1205 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
1206 new_iov = kmalloc_array(n_vec + 1, sizeof(struct kvec),
1209 /* otherwise cifs_send_recv below sets resp_buf_type */
1210 *resp_buf_type = CIFS_NO_BUFFER;
1216 /* 1st iov is a RFC1001 length followed by the rest of the packet */
1217 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
1219 new_iov[0].iov_base = new_iov[1].iov_base;
1220 new_iov[0].iov_len = 4;
1221 new_iov[1].iov_base += 4;
1222 new_iov[1].iov_len -= 4;
1224 memset(&rqst, 0, sizeof(struct smb_rqst));
1225 rqst.rq_iov = new_iov;
1226 rqst.rq_nvec = n_vec + 1;
1228 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
1229 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
1235 SendReceive(const unsigned int xid, struct cifs_ses *ses,
1236 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1237 int *pbytes_returned, const int flags)
1240 struct mid_q_entry *midQ;
1241 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1242 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1243 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1244 struct cifs_credits credits = { .value = 1, .instance = 0 };
1247 cifs_dbg(VFS, "Null smb session\n");
1250 if (ses->server == NULL) {
1251 cifs_dbg(VFS, "Null tcp session\n");
1255 if (ses->server->tcpStatus == CifsExiting)
1258 /* Ensure that we do not send more than 50 overlapping requests
1259 to the same server. We may make this configurable later or
1262 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1263 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1268 rc = wait_for_free_request(ses->server, flags, &credits.instance);
1272 /* make sure that we sign in the same order that we send on this socket
1273 and avoid races inside tcp sendmsg code that could cause corruption
1276 mutex_lock(&ses->server->srv_mutex);
1278 rc = allocate_mid(ses, in_buf, &midQ);
1280 mutex_unlock(&ses->server->srv_mutex);
1281 /* Update # of requests on wire to server */
1282 add_credits(ses->server, &credits, 0);
1286 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
1288 mutex_unlock(&ses->server->srv_mutex);
1292 midQ->mid_state = MID_REQUEST_SUBMITTED;
1294 cifs_in_send_inc(ses->server);
1295 rc = smb_send(ses->server, in_buf, len);
1296 cifs_in_send_dec(ses->server);
1297 cifs_save_when_sent(midQ);
1300 ses->server->sequence_number -= 2;
1302 mutex_unlock(&ses->server->srv_mutex);
1307 rc = wait_for_response(ses->server, midQ);
1309 send_cancel(ses->server, &rqst, midQ);
1310 spin_lock(&GlobalMid_Lock);
1311 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1312 /* no longer considered to be "in-flight" */
1313 midQ->callback = DeleteMidQEntry;
1314 spin_unlock(&GlobalMid_Lock);
1315 add_credits(ses->server, &credits, 0);
1318 spin_unlock(&GlobalMid_Lock);
1321 rc = cifs_sync_mid_result(midQ, ses->server);
1323 add_credits(ses->server, &credits, 0);
1327 if (!midQ->resp_buf || !out_buf ||
1328 midQ->mid_state != MID_RESPONSE_RECEIVED) {
1330 cifs_dbg(VFS, "Bad MID state?\n");
1334 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1335 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1336 rc = cifs_check_receive(midQ, ses->server, 0);
1338 cifs_delete_mid(midQ);
1339 add_credits(ses->server, &credits, 0);
1344 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
1345 blocking lock to return. */
1348 send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
1349 struct smb_hdr *in_buf,
1350 struct smb_hdr *out_buf)
1353 struct cifs_ses *ses = tcon->ses;
1354 LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
1356 /* We just modify the current in_buf to change
1357 the type of lock from LOCKING_ANDX_SHARED_LOCK
1358 or LOCKING_ANDX_EXCLUSIVE_LOCK to
1359 LOCKING_ANDX_CANCEL_LOCK. */
1361 pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
1363 pSMB->hdr.Mid = get_next_mid(ses->server);
1365 return SendReceive(xid, ses, in_buf, out_buf,
1366 &bytes_returned, 0);
1370 SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
1371 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1372 int *pbytes_returned)
1376 struct mid_q_entry *midQ;
1377 struct cifs_ses *ses;
1378 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1379 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1380 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1381 unsigned int instance;
1383 if (tcon == NULL || tcon->ses == NULL) {
1384 cifs_dbg(VFS, "Null smb session\n");
1389 if (ses->server == NULL) {
1390 cifs_dbg(VFS, "Null tcp session\n");
1394 if (ses->server->tcpStatus == CifsExiting)
1397 /* Ensure that we do not send more than 50 overlapping requests
1398 to the same server. We may make this configurable later or
1401 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1402 cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1407 rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, &instance);
1411 /* make sure that we sign in the same order that we send on this socket
1412 and avoid races inside tcp sendmsg code that could cause corruption
1415 mutex_lock(&ses->server->srv_mutex);
1417 rc = allocate_mid(ses, in_buf, &midQ);
1419 mutex_unlock(&ses->server->srv_mutex);
1423 rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
1425 cifs_delete_mid(midQ);
1426 mutex_unlock(&ses->server->srv_mutex);
1430 midQ->mid_state = MID_REQUEST_SUBMITTED;
1431 cifs_in_send_inc(ses->server);
1432 rc = smb_send(ses->server, in_buf, len);
1433 cifs_in_send_dec(ses->server);
1434 cifs_save_when_sent(midQ);
1437 ses->server->sequence_number -= 2;
1439 mutex_unlock(&ses->server->srv_mutex);
1442 cifs_delete_mid(midQ);
1446 /* Wait for a reply - allow signals to interrupt. */
1447 rc = wait_event_interruptible(ses->server->response_q,
1448 (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
1449 ((ses->server->tcpStatus != CifsGood) &&
1450 (ses->server->tcpStatus != CifsNew)));
1452 /* Were we interrupted by a signal ? */
1453 if ((rc == -ERESTARTSYS) &&
1454 (midQ->mid_state == MID_REQUEST_SUBMITTED) &&
1455 ((ses->server->tcpStatus == CifsGood) ||
1456 (ses->server->tcpStatus == CifsNew))) {
1458 if (in_buf->Command == SMB_COM_TRANSACTION2) {
1459 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1460 blocking lock to return. */
1461 rc = send_cancel(ses->server, &rqst, midQ);
1463 cifs_delete_mid(midQ);
1467 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1468 to cause the blocking lock to return. */
1470 rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
1472 /* If we get -ENOLCK back the lock may have
1473 already been removed. Don't exit in this case. */
1474 if (rc && rc != -ENOLCK) {
1475 cifs_delete_mid(midQ);
1480 rc = wait_for_response(ses->server, midQ);
1482 send_cancel(ses->server, &rqst, midQ);
1483 spin_lock(&GlobalMid_Lock);
1484 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1485 /* no longer considered to be "in-flight" */
1486 midQ->callback = DeleteMidQEntry;
1487 spin_unlock(&GlobalMid_Lock);
1490 spin_unlock(&GlobalMid_Lock);
1493 /* We got the response - restart system call. */
1497 rc = cifs_sync_mid_result(midQ, ses->server);
1501 /* rcvd frame is ok */
1502 if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) {
1504 cifs_dbg(VFS, "Bad MID state?\n");
1508 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1509 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1510 rc = cifs_check_receive(midQ, ses->server, 0);
1512 cifs_delete_mid(midQ);
1513 if (rstart && rc == -EACCES)
1514 return -ERESTARTSYS;