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_server_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_server_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_server_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_server_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_server_dbg(VFS, "Encryption requested but transform "
477 "callback is missing\n");
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 */
535 if (server->in_flight > server->max_in_flight)
536 server->max_in_flight = server->in_flight;
538 *instance = server->reconnect_instance;
539 spin_unlock(&server->req_lock);
544 if (*credits < num_credits) {
545 spin_unlock(&server->req_lock);
546 cifs_num_waiters_inc(server);
547 rc = wait_event_killable_timeout(server->request_q,
548 has_credits(server, credits, num_credits), t);
549 cifs_num_waiters_dec(server);
551 trace_smb3_credit_timeout(server->CurrentMid,
552 server->hostname, num_credits);
553 cifs_server_dbg(VFS, "wait timed out after %d ms\n",
557 if (rc == -ERESTARTSYS)
559 spin_lock(&server->req_lock);
561 if (server->tcpStatus == CifsExiting) {
562 spin_unlock(&server->req_lock);
567 * For normal commands, reserve the last MAX_COMPOUND
568 * credits to compound requests.
569 * Otherwise these compounds could be permanently
570 * starved for credits by single-credit requests.
572 * To prevent spinning CPU, block this thread until
573 * there are >MAX_COMPOUND credits available.
574 * But only do this is we already have a lot of
575 * credits in flight to avoid triggering this check
576 * for servers that are slow to hand out credits on
579 if (!optype && num_credits == 1 &&
580 server->in_flight > 2 * MAX_COMPOUND &&
581 *credits <= MAX_COMPOUND) {
582 spin_unlock(&server->req_lock);
583 cifs_num_waiters_inc(server);
584 rc = wait_event_killable_timeout(
586 has_credits(server, credits,
589 cifs_num_waiters_dec(server);
591 trace_smb3_credit_timeout(
593 server->hostname, num_credits);
594 cifs_server_dbg(VFS, "wait timed out after %d ms\n",
598 if (rc == -ERESTARTSYS)
600 spin_lock(&server->req_lock);
605 * Can not count locking commands against total
606 * as they are allowed to block on server.
609 /* update # of requests on the wire to server */
610 if ((flags & CIFS_TIMEOUT_MASK) != CIFS_BLOCKING_OP) {
611 *credits -= num_credits;
612 server->in_flight += num_credits;
613 if (server->in_flight > server->max_in_flight)
614 server->max_in_flight = server->in_flight;
615 *instance = server->reconnect_instance;
617 spin_unlock(&server->req_lock);
625 wait_for_free_request(struct TCP_Server_Info *server, const int flags,
626 unsigned int *instance)
628 return wait_for_free_credits(server, 1, -1, flags,
633 wait_for_compound_request(struct TCP_Server_Info *server, int num,
634 const int flags, unsigned int *instance)
638 credits = server->ops->get_credits_field(server, flags & CIFS_OP_MASK);
640 spin_lock(&server->req_lock);
641 if (*credits < num) {
643 * Return immediately if not too many requests in flight since
644 * we will likely be stuck on waiting for credits.
646 if (server->in_flight < num - *credits) {
647 spin_unlock(&server->req_lock);
651 spin_unlock(&server->req_lock);
653 return wait_for_free_credits(server, num, 60000, flags,
658 cifs_wait_mtu_credits(struct TCP_Server_Info *server, unsigned int size,
659 unsigned int *num, struct cifs_credits *credits)
663 credits->instance = server->reconnect_instance;
667 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
668 struct mid_q_entry **ppmidQ)
670 if (ses->server->tcpStatus == CifsExiting) {
674 if (ses->server->tcpStatus == CifsNeedReconnect) {
675 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
679 if (ses->status == CifsNew) {
680 if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
681 (in_buf->Command != SMB_COM_NEGOTIATE))
683 /* else ok - we are setting up session */
686 if (ses->status == CifsExiting) {
687 /* check if SMB session is bad because we are setting it up */
688 if (in_buf->Command != SMB_COM_LOGOFF_ANDX)
690 /* else ok - we are shutting down session */
693 *ppmidQ = AllocMidQEntry(in_buf, ses->server);
696 spin_lock(&GlobalMid_Lock);
697 list_add_tail(&(*ppmidQ)->qhead, &ses->server->pending_mid_q);
698 spin_unlock(&GlobalMid_Lock);
703 wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
707 error = wait_event_freezekillable_unsafe(server->response_q,
708 midQ->mid_state != MID_REQUEST_SUBMITTED);
716 cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
719 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
720 struct mid_q_entry *mid;
722 if (rqst->rq_iov[0].iov_len != 4 ||
723 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
724 return ERR_PTR(-EIO);
726 /* enable signing if server requires it */
728 hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
730 mid = AllocMidQEntry(hdr, server);
732 return ERR_PTR(-ENOMEM);
734 rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
736 DeleteMidQEntry(mid);
744 * Send a SMB request and set the callback function in the mid to handle
745 * the result. Caller is responsible for dealing with timeouts.
748 cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
749 mid_receive_t *receive, mid_callback_t *callback,
750 mid_handle_t *handle, void *cbdata, const int flags,
751 const struct cifs_credits *exist_credits)
754 struct mid_q_entry *mid;
755 struct cifs_credits credits = { .value = 0, .instance = 0 };
756 unsigned int instance;
759 optype = flags & CIFS_OP_MASK;
761 if ((flags & CIFS_HAS_CREDITS) == 0) {
762 rc = wait_for_free_request(server, flags, &instance);
766 credits.instance = instance;
768 instance = exist_credits->instance;
770 mutex_lock(&server->srv_mutex);
773 * We can't use credits obtained from the previous session to send this
774 * request. Check if there were reconnects after we obtained credits and
775 * return -EAGAIN in such cases to let callers handle it.
777 if (instance != server->reconnect_instance) {
778 mutex_unlock(&server->srv_mutex);
779 add_credits_and_wake_if(server, &credits, optype);
783 mid = server->ops->setup_async_request(server, rqst);
785 mutex_unlock(&server->srv_mutex);
786 add_credits_and_wake_if(server, &credits, optype);
790 mid->receive = receive;
791 mid->callback = callback;
792 mid->callback_data = cbdata;
793 mid->handle = handle;
794 mid->mid_state = MID_REQUEST_SUBMITTED;
796 /* put it on the pending_mid_q */
797 spin_lock(&GlobalMid_Lock);
798 list_add_tail(&mid->qhead, &server->pending_mid_q);
799 spin_unlock(&GlobalMid_Lock);
802 * Need to store the time in mid before calling I/O. For call_async,
803 * I/O response may come back and free the mid entry on another thread.
805 cifs_save_when_sent(mid);
806 cifs_in_send_inc(server);
807 rc = smb_send_rqst(server, 1, rqst, flags);
808 cifs_in_send_dec(server);
811 revert_current_mid(server, mid->credits);
812 server->sequence_number -= 2;
813 cifs_delete_mid(mid);
816 mutex_unlock(&server->srv_mutex);
821 add_credits_and_wake_if(server, &credits, optype);
827 * Send an SMB Request. No response info (other than return code)
828 * needs to be parsed.
830 * flags indicate the type of request buffer and how long to wait
831 * and whether to log NT STATUS code (error) before mapping it to POSIX error
835 SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
836 char *in_buf, int flags)
843 iov[0].iov_base = in_buf;
844 iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
845 flags |= CIFS_NO_RSP_BUF;
846 rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags, &rsp_iov);
847 cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
853 cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
857 cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n",
858 __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state);
860 spin_lock(&GlobalMid_Lock);
861 switch (mid->mid_state) {
862 case MID_RESPONSE_RECEIVED:
863 spin_unlock(&GlobalMid_Lock);
865 case MID_RETRY_NEEDED:
868 case MID_RESPONSE_MALFORMED:
875 list_del_init(&mid->qhead);
876 cifs_server_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
877 __func__, mid->mid, mid->mid_state);
880 spin_unlock(&GlobalMid_Lock);
882 DeleteMidQEntry(mid);
887 send_cancel(struct TCP_Server_Info *server, struct smb_rqst *rqst,
888 struct mid_q_entry *mid)
890 return server->ops->send_cancel ?
891 server->ops->send_cancel(server, rqst, mid) : 0;
895 cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
898 unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
900 dump_smb(mid->resp_buf, min_t(u32, 92, len));
902 /* convert the length into a more usable form */
906 struct smb_rqst rqst = { .rq_iov = iov,
909 iov[0].iov_base = mid->resp_buf;
911 iov[1].iov_base = (char *)mid->resp_buf + 4;
912 iov[1].iov_len = len - 4;
913 /* FIXME: add code to kill session */
914 rc = cifs_verify_signature(&rqst, server,
915 mid->sequence_number);
917 cifs_server_dbg(VFS, "SMB signature verification returned error = %d\n",
921 /* BB special case reconnect tid and uid here? */
922 return map_smb_to_linux_error(mid->resp_buf, log_error);
926 cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
929 struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
930 struct mid_q_entry *mid;
932 if (rqst->rq_iov[0].iov_len != 4 ||
933 rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
934 return ERR_PTR(-EIO);
936 rc = allocate_mid(ses, hdr, &mid);
939 rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
941 cifs_delete_mid(mid);
948 cifs_compound_callback(struct mid_q_entry *mid)
950 struct TCP_Server_Info *server = mid->server;
951 struct cifs_credits credits;
953 credits.value = server->ops->get_credits(mid);
954 credits.instance = server->reconnect_instance;
956 add_credits(server, &credits, mid->optype);
960 cifs_compound_last_callback(struct mid_q_entry *mid)
962 cifs_compound_callback(mid);
963 cifs_wake_up_task(mid);
967 cifs_cancelled_callback(struct mid_q_entry *mid)
969 cifs_compound_callback(mid);
970 DeleteMidQEntry(mid);
974 compound_send_recv(const unsigned int xid, struct cifs_ses *ses,
975 const int flags, const int num_rqst, struct smb_rqst *rqst,
976 int *resp_buf_type, struct kvec *resp_iov)
978 int i, j, optype, rc = 0;
979 struct mid_q_entry *midQ[MAX_COMPOUND];
980 bool cancelled_mid[MAX_COMPOUND] = {false};
981 struct cifs_credits credits[MAX_COMPOUND] = {
982 { .value = 0, .instance = 0 }
984 unsigned int instance;
986 struct TCP_Server_Info *server;
988 optype = flags & CIFS_OP_MASK;
990 for (i = 0; i < num_rqst; i++)
991 resp_buf_type[i] = CIFS_NO_BUFFER; /* no response buf yet */
993 if ((ses == NULL) || (ses->server == NULL)) {
994 cifs_dbg(VFS, "Null session\n");
998 server = ses->server;
999 if (server->tcpStatus == CifsExiting)
1003 * Wait for all the requests to become available.
1004 * This approach still leaves the possibility to be stuck waiting for
1005 * credits if the server doesn't grant credits to the outstanding
1006 * requests and if the client is completely idle, not generating any
1008 * This can be handled by the eventual session reconnect.
1010 rc = wait_for_compound_request(server, num_rqst, flags,
1015 for (i = 0; i < num_rqst; i++) {
1016 credits[i].value = 1;
1017 credits[i].instance = instance;
1021 * Make sure that we sign in the same order that we send on this socket
1022 * and avoid races inside tcp sendmsg code that could cause corruption
1026 mutex_lock(&server->srv_mutex);
1029 * All the parts of the compound chain belong obtained credits from the
1030 * same session. We can not use credits obtained from the previous
1031 * session to send this request. Check if there were reconnects after
1032 * we obtained credits and return -EAGAIN in such cases to let callers
1035 if (instance != server->reconnect_instance) {
1036 mutex_unlock(&server->srv_mutex);
1037 for (j = 0; j < num_rqst; j++)
1038 add_credits(server, &credits[j], optype);
1042 for (i = 0; i < num_rqst; i++) {
1043 midQ[i] = server->ops->setup_request(ses, &rqst[i]);
1044 if (IS_ERR(midQ[i])) {
1045 revert_current_mid(server, i);
1046 for (j = 0; j < i; j++)
1047 cifs_delete_mid(midQ[j]);
1048 mutex_unlock(&server->srv_mutex);
1050 /* Update # of requests on wire to server */
1051 for (j = 0; j < num_rqst; j++)
1052 add_credits(server, &credits[j], optype);
1053 return PTR_ERR(midQ[i]);
1056 midQ[i]->mid_state = MID_REQUEST_SUBMITTED;
1057 midQ[i]->optype = optype;
1059 * Invoke callback for every part of the compound chain
1060 * to calculate credits properly. Wake up this thread only when
1061 * the last element is received.
1063 if (i < num_rqst - 1)
1064 midQ[i]->callback = cifs_compound_callback;
1066 midQ[i]->callback = cifs_compound_last_callback;
1068 cifs_in_send_inc(server);
1069 rc = smb_send_rqst(server, num_rqst, rqst, flags);
1070 cifs_in_send_dec(server);
1072 for (i = 0; i < num_rqst; i++)
1073 cifs_save_when_sent(midQ[i]);
1076 revert_current_mid(server, num_rqst);
1077 server->sequence_number -= 2;
1080 mutex_unlock(&server->srv_mutex);
1083 * If sending failed for some reason or it is an oplock break that we
1084 * will not receive a response to - return credits back
1086 if (rc < 0 || (flags & CIFS_NO_SRV_RSP)) {
1087 for (i = 0; i < num_rqst; i++)
1088 add_credits(server, &credits[i], optype);
1093 * At this point the request is passed to the network stack - we assume
1094 * that any credits taken from the server structure on the client have
1095 * been spent and we can't return them back. Once we receive responses
1096 * we will collect credits granted by the server in the mid callbacks
1097 * and add those credits to the server structure.
1101 * Compounding is never used during session establish.
1103 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP))
1104 smb311_update_preauth_hash(ses, rqst[0].rq_iov,
1107 for (i = 0; i < num_rqst; i++) {
1108 rc = wait_for_response(server, midQ[i]);
1113 for (; i < num_rqst; i++) {
1114 cifs_server_dbg(VFS, "Cancelling wait for mid %llu cmd: %d\n",
1115 midQ[i]->mid, le16_to_cpu(midQ[i]->command));
1116 send_cancel(server, &rqst[i], midQ[i]);
1117 spin_lock(&GlobalMid_Lock);
1118 if (midQ[i]->mid_state == MID_REQUEST_SUBMITTED) {
1119 midQ[i]->mid_flags |= MID_WAIT_CANCELLED;
1120 midQ[i]->callback = cifs_cancelled_callback;
1121 cancelled_mid[i] = true;
1122 credits[i].value = 0;
1124 spin_unlock(&GlobalMid_Lock);
1128 for (i = 0; i < num_rqst; i++) {
1132 rc = cifs_sync_mid_result(midQ[i], server);
1134 /* mark this mid as cancelled to not free it below */
1135 cancelled_mid[i] = true;
1139 if (!midQ[i]->resp_buf ||
1140 midQ[i]->mid_state != MID_RESPONSE_RECEIVED) {
1142 cifs_dbg(FYI, "Bad MID state?\n");
1146 buf = (char *)midQ[i]->resp_buf;
1147 resp_iov[i].iov_base = buf;
1148 resp_iov[i].iov_len = midQ[i]->resp_buf_size +
1149 server->vals->header_preamble_size;
1151 if (midQ[i]->large_buf)
1152 resp_buf_type[i] = CIFS_LARGE_BUFFER;
1154 resp_buf_type[i] = CIFS_SMALL_BUFFER;
1156 rc = server->ops->check_receive(midQ[i], server,
1157 flags & CIFS_LOG_ERROR);
1159 /* mark it so buf will not be freed by cifs_delete_mid */
1160 if ((flags & CIFS_NO_RSP_BUF) == 0)
1161 midQ[i]->resp_buf = NULL;
1166 * Compounding is never used during session establish.
1168 if ((ses->status == CifsNew) || (optype & CIFS_NEG_OP)) {
1170 .iov_base = resp_iov[0].iov_base,
1171 .iov_len = resp_iov[0].iov_len
1173 smb311_update_preauth_hash(ses, &iov, 1);
1178 * This will dequeue all mids. After this it is important that the
1179 * demultiplex_thread will not process any of these mids any futher.
1180 * This is prevented above by using a noop callback that will not
1181 * wake this thread except for the very last PDU.
1183 for (i = 0; i < num_rqst; i++) {
1184 if (!cancelled_mid[i])
1185 cifs_delete_mid(midQ[i]);
1192 cifs_send_recv(const unsigned int xid, struct cifs_ses *ses,
1193 struct smb_rqst *rqst, int *resp_buf_type, const int flags,
1194 struct kvec *resp_iov)
1196 return compound_send_recv(xid, ses, flags, 1, rqst, resp_buf_type,
1201 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
1202 struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
1203 const int flags, struct kvec *resp_iov)
1205 struct smb_rqst rqst;
1206 struct kvec s_iov[CIFS_MAX_IOV_SIZE], *new_iov;
1209 if (n_vec + 1 > CIFS_MAX_IOV_SIZE) {
1210 new_iov = kmalloc_array(n_vec + 1, sizeof(struct kvec),
1213 /* otherwise cifs_send_recv below sets resp_buf_type */
1214 *resp_buf_type = CIFS_NO_BUFFER;
1220 /* 1st iov is a RFC1001 length followed by the rest of the packet */
1221 memcpy(new_iov + 1, iov, (sizeof(struct kvec) * n_vec));
1223 new_iov[0].iov_base = new_iov[1].iov_base;
1224 new_iov[0].iov_len = 4;
1225 new_iov[1].iov_base += 4;
1226 new_iov[1].iov_len -= 4;
1228 memset(&rqst, 0, sizeof(struct smb_rqst));
1229 rqst.rq_iov = new_iov;
1230 rqst.rq_nvec = n_vec + 1;
1232 rc = cifs_send_recv(xid, ses, &rqst, resp_buf_type, flags, resp_iov);
1233 if (n_vec + 1 > CIFS_MAX_IOV_SIZE)
1239 SendReceive(const unsigned int xid, struct cifs_ses *ses,
1240 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1241 int *pbytes_returned, const int flags)
1244 struct mid_q_entry *midQ;
1245 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1246 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1247 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1248 struct cifs_credits credits = { .value = 1, .instance = 0 };
1249 struct TCP_Server_Info *server;
1252 cifs_dbg(VFS, "Null smb session\n");
1255 server = ses->server;
1256 if (server == NULL) {
1257 cifs_dbg(VFS, "Null tcp session\n");
1261 if (server->tcpStatus == CifsExiting)
1264 /* Ensure that we do not send more than 50 overlapping requests
1265 to the same server. We may make this configurable later or
1268 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1269 cifs_server_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1274 rc = wait_for_free_request(server, flags, &credits.instance);
1278 /* make sure that we sign in the same order that we send on this socket
1279 and avoid races inside tcp sendmsg code that could cause corruption
1282 mutex_lock(&server->srv_mutex);
1284 rc = allocate_mid(ses, in_buf, &midQ);
1286 mutex_unlock(&ses->server->srv_mutex);
1287 /* Update # of requests on wire to server */
1288 add_credits(server, &credits, 0);
1292 rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
1294 mutex_unlock(&server->srv_mutex);
1298 midQ->mid_state = MID_REQUEST_SUBMITTED;
1300 cifs_in_send_inc(server);
1301 rc = smb_send(server, in_buf, len);
1302 cifs_in_send_dec(server);
1303 cifs_save_when_sent(midQ);
1306 server->sequence_number -= 2;
1308 mutex_unlock(&server->srv_mutex);
1313 rc = wait_for_response(server, midQ);
1315 send_cancel(server, &rqst, midQ);
1316 spin_lock(&GlobalMid_Lock);
1317 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1318 /* no longer considered to be "in-flight" */
1319 midQ->callback = DeleteMidQEntry;
1320 spin_unlock(&GlobalMid_Lock);
1321 add_credits(server, &credits, 0);
1324 spin_unlock(&GlobalMid_Lock);
1327 rc = cifs_sync_mid_result(midQ, server);
1329 add_credits(server, &credits, 0);
1333 if (!midQ->resp_buf || !out_buf ||
1334 midQ->mid_state != MID_RESPONSE_RECEIVED) {
1336 cifs_server_dbg(VFS, "Bad MID state?\n");
1340 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1341 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1342 rc = cifs_check_receive(midQ, server, 0);
1344 cifs_delete_mid(midQ);
1345 add_credits(server, &credits, 0);
1350 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
1351 blocking lock to return. */
1354 send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
1355 struct smb_hdr *in_buf,
1356 struct smb_hdr *out_buf)
1359 struct cifs_ses *ses = tcon->ses;
1360 LOCK_REQ *pSMB = (LOCK_REQ *)in_buf;
1362 /* We just modify the current in_buf to change
1363 the type of lock from LOCKING_ANDX_SHARED_LOCK
1364 or LOCKING_ANDX_EXCLUSIVE_LOCK to
1365 LOCKING_ANDX_CANCEL_LOCK. */
1367 pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
1369 pSMB->hdr.Mid = get_next_mid(ses->server);
1371 return SendReceive(xid, ses, in_buf, out_buf,
1372 &bytes_returned, 0);
1376 SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
1377 struct smb_hdr *in_buf, struct smb_hdr *out_buf,
1378 int *pbytes_returned)
1382 struct mid_q_entry *midQ;
1383 struct cifs_ses *ses;
1384 unsigned int len = be32_to_cpu(in_buf->smb_buf_length);
1385 struct kvec iov = { .iov_base = in_buf, .iov_len = len };
1386 struct smb_rqst rqst = { .rq_iov = &iov, .rq_nvec = 1 };
1387 unsigned int instance;
1388 struct TCP_Server_Info *server;
1390 if (tcon == NULL || tcon->ses == NULL) {
1391 cifs_dbg(VFS, "Null smb session\n");
1395 server = ses->server;
1397 if (server == NULL) {
1398 cifs_dbg(VFS, "Null tcp session\n");
1402 if (server->tcpStatus == CifsExiting)
1405 /* Ensure that we do not send more than 50 overlapping requests
1406 to the same server. We may make this configurable later or
1409 if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) {
1410 cifs_tcon_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
1415 rc = wait_for_free_request(server, CIFS_BLOCKING_OP, &instance);
1419 /* make sure that we sign in the same order that we send on this socket
1420 and avoid races inside tcp sendmsg code that could cause corruption
1423 mutex_lock(&server->srv_mutex);
1425 rc = allocate_mid(ses, in_buf, &midQ);
1427 mutex_unlock(&server->srv_mutex);
1431 rc = cifs_sign_smb(in_buf, server, &midQ->sequence_number);
1433 cifs_delete_mid(midQ);
1434 mutex_unlock(&server->srv_mutex);
1438 midQ->mid_state = MID_REQUEST_SUBMITTED;
1439 cifs_in_send_inc(server);
1440 rc = smb_send(server, in_buf, len);
1441 cifs_in_send_dec(server);
1442 cifs_save_when_sent(midQ);
1445 server->sequence_number -= 2;
1447 mutex_unlock(&server->srv_mutex);
1450 cifs_delete_mid(midQ);
1454 /* Wait for a reply - allow signals to interrupt. */
1455 rc = wait_event_interruptible(server->response_q,
1456 (!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
1457 ((server->tcpStatus != CifsGood) &&
1458 (server->tcpStatus != CifsNew)));
1460 /* Were we interrupted by a signal ? */
1461 if ((rc == -ERESTARTSYS) &&
1462 (midQ->mid_state == MID_REQUEST_SUBMITTED) &&
1463 ((server->tcpStatus == CifsGood) ||
1464 (server->tcpStatus == CifsNew))) {
1466 if (in_buf->Command == SMB_COM_TRANSACTION2) {
1467 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1468 blocking lock to return. */
1469 rc = send_cancel(server, &rqst, midQ);
1471 cifs_delete_mid(midQ);
1475 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1476 to cause the blocking lock to return. */
1478 rc = send_lock_cancel(xid, tcon, in_buf, out_buf);
1480 /* If we get -ENOLCK back the lock may have
1481 already been removed. Don't exit in this case. */
1482 if (rc && rc != -ENOLCK) {
1483 cifs_delete_mid(midQ);
1488 rc = wait_for_response(server, midQ);
1490 send_cancel(server, &rqst, midQ);
1491 spin_lock(&GlobalMid_Lock);
1492 if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
1493 /* no longer considered to be "in-flight" */
1494 midQ->callback = DeleteMidQEntry;
1495 spin_unlock(&GlobalMid_Lock);
1498 spin_unlock(&GlobalMid_Lock);
1501 /* We got the response - restart system call. */
1505 rc = cifs_sync_mid_result(midQ, server);
1509 /* rcvd frame is ok */
1510 if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) {
1512 cifs_tcon_dbg(VFS, "Bad MID state?\n");
1516 *pbytes_returned = get_rfc1002_length(midQ->resp_buf);
1517 memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
1518 rc = cifs_check_receive(midQ, server, 0);
1520 cifs_delete_mid(midQ);
1521 if (rstart && rc == -EACCES)
1522 return -ERESTARTSYS;