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/highmem.h>
32 #include <asm/uaccess.h>
33 #include <asm/processor.h>
34 #include <linux/mempool.h>
37 #include "cifsproto.h"
38 #include "cifs_debug.h"
41 cifs_wake_up_task(struct mid_q_entry
*mid
)
43 wake_up_process(mid
->callback_data
);
47 AllocMidQEntry(const struct smb_hdr
*smb_buffer
, struct TCP_Server_Info
*server
)
49 struct mid_q_entry
*temp
;
52 cifs_dbg(VFS
, "Null TCP session in AllocMidQEntry\n");
56 temp
= mempool_alloc(cifs_mid_poolp
, GFP_NOFS
);
60 memset(temp
, 0, sizeof(struct mid_q_entry
));
61 temp
->mid
= smb_buffer
->Mid
; /* always LE */
62 temp
->pid
= current
->pid
;
63 temp
->command
= cpu_to_le16(smb_buffer
->Command
);
64 cifs_dbg(FYI
, "For smb_command %d\n", smb_buffer
->Command
);
65 /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
66 /* when mid allocated can be before when sent */
67 temp
->when_alloc
= jiffies
;
68 temp
->server
= server
;
71 * The default is for the mid to be synchronous, so the
72 * default callback just wakes up the current task.
74 temp
->callback
= cifs_wake_up_task
;
75 temp
->callback_data
= current
;
78 atomic_inc(&midCount
);
79 temp
->mid_state
= MID_REQUEST_ALLOCATED
;
84 DeleteMidQEntry(struct mid_q_entry
*midEntry
)
86 #ifdef CONFIG_CIFS_STATS2
87 __le16 command
= midEntry
->server
->vals
->lock_cmd
;
90 midEntry
->mid_state
= MID_FREE
;
91 atomic_dec(&midCount
);
92 if (midEntry
->large_buf
)
93 cifs_buf_release(midEntry
->resp_buf
);
95 cifs_small_buf_release(midEntry
->resp_buf
);
96 #ifdef CONFIG_CIFS_STATS2
98 /* commands taking longer than one second are indications that
99 something is wrong, unless it is quite a slow link or server */
100 if ((now
- midEntry
->when_alloc
) > HZ
) {
101 if ((cifsFYI
& CIFS_TIMER
) && (midEntry
->command
!= command
)) {
102 printk(KERN_DEBUG
" CIFS slow rsp: cmd %d mid %llu",
103 midEntry
->command
, midEntry
->mid
);
104 printk(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
105 now
- midEntry
->when_alloc
,
106 now
- midEntry
->when_sent
,
107 now
- midEntry
->when_received
);
111 mempool_free(midEntry
, cifs_mid_poolp
);
115 cifs_delete_mid(struct mid_q_entry
*mid
)
117 spin_lock(&GlobalMid_Lock
);
118 list_del(&mid
->qhead
);
119 spin_unlock(&GlobalMid_Lock
);
121 DeleteMidQEntry(mid
);
125 * smb_send_kvec - send an array of kvecs to the server
126 * @server: Server to send the data to
127 * @iov: Pointer to array of kvecs
128 * @n_vec: length of kvec array
129 * @sent: amount of data sent on socket is stored here
131 * Our basic "send data to server" function. Should be called with srv_mutex
132 * held. The caller is responsible for handling the results.
135 smb_send_kvec(struct TCP_Server_Info
*server
, struct kvec
*iov
, size_t n_vec
,
140 struct msghdr smb_msg
;
141 unsigned int remaining
;
142 size_t first_vec
= 0;
143 struct socket
*ssocket
= server
->ssocket
;
147 smb_msg
.msg_name
= (struct sockaddr
*) &server
->dstaddr
;
148 smb_msg
.msg_namelen
= sizeof(struct sockaddr
);
149 smb_msg
.msg_control
= NULL
;
150 smb_msg
.msg_controllen
= 0;
151 if (server
->noblocksnd
)
152 smb_msg
.msg_flags
= MSG_DONTWAIT
+ MSG_NOSIGNAL
;
154 smb_msg
.msg_flags
= MSG_NOSIGNAL
;
157 for (i
= 0; i
< n_vec
; i
++)
158 remaining
+= iov
[i
].iov_len
;
163 * If blocking send, we try 3 times, since each can block
164 * for 5 seconds. For nonblocking we have to try more
165 * but wait increasing amounts of time allowing time for
166 * socket to clear. The overall time we wait in either
167 * case to send on the socket is about 15 seconds.
168 * Similarly we wait for 15 seconds for a response from
169 * the server in SendReceive[2] for the server to send
170 * a response back for most types of requests (except
171 * SMB Write past end of file which can be slow, and
172 * blocking lock operations). NFS waits slightly longer
173 * than CIFS, but this can make it take longer for
174 * nonresponsive servers to be detected and 15 seconds
175 * is more than enough time for modern networks to
176 * send a packet. In most cases if we fail to send
177 * after the retries we will kill the socket and
178 * reconnect which may clear the network problem.
180 rc
= kernel_sendmsg(ssocket
, &smb_msg
, &iov
[first_vec
],
181 n_vec
- first_vec
, remaining
);
184 if (i
>= 14 || (!server
->noblocksnd
&& (i
> 2))) {
185 cifs_dbg(VFS
, "sends on sock %p stuck for 15 seconds\n",
197 /* send was at least partially successful */
200 if (rc
== remaining
) {
205 if (rc
> remaining
) {
206 cifs_dbg(VFS
, "sent %d requested %d\n", rc
, remaining
);
211 /* should never happen, letting socket clear before
212 retrying is our only obvious option here */
213 cifs_dbg(VFS
, "tcp sent no data\n");
220 /* the line below resets i */
221 for (i
= first_vec
; i
< n_vec
; i
++) {
222 if (iov
[i
].iov_len
) {
223 if (rc
> iov
[i
].iov_len
) {
224 rc
-= iov
[i
].iov_len
;
227 iov
[i
].iov_base
+= rc
;
228 iov
[i
].iov_len
-= rc
;
235 i
= 0; /* in case we get ENOSPC on the next send */
242 * rqst_page_to_kvec - Turn a slot in the smb_rqst page array into a kvec
243 * @rqst: pointer to smb_rqst
244 * @idx: index into the array of the page
245 * @iov: pointer to struct kvec that will hold the result
247 * Helper function to convert a slot in the rqst->rq_pages array into a kvec.
248 * The page will be kmapped and the address placed into iov_base. The length
249 * will then be adjusted according to the ptailoff.
252 cifs_rqst_page_to_kvec(struct smb_rqst
*rqst
, unsigned int idx
,
256 * FIXME: We could avoid this kmap altogether if we used
257 * kernel_sendpage instead of kernel_sendmsg. That will only
258 * work if signing is disabled though as sendpage inlines the
259 * page directly into the fraglist. If userspace modifies the
260 * page after we calculate the signature, then the server will
261 * reject it and may break the connection. kernel_sendmsg does
262 * an extra copy of the data and avoids that issue.
264 iov
->iov_base
= kmap(rqst
->rq_pages
[idx
]);
266 /* if last page, don't send beyond this offset into page */
267 if (idx
== (rqst
->rq_npages
- 1))
268 iov
->iov_len
= rqst
->rq_tailsz
;
270 iov
->iov_len
= rqst
->rq_pagesz
;
274 smb_send_rqst(struct TCP_Server_Info
*server
, struct smb_rqst
*rqst
)
277 struct kvec
*iov
= rqst
->rq_iov
;
278 int n_vec
= rqst
->rq_nvec
;
279 unsigned int smb_buf_length
= get_rfc1002_length(iov
[0].iov_base
);
281 size_t total_len
= 0, sent
;
282 struct socket
*ssocket
= server
->ssocket
;
288 cifs_dbg(FYI
, "Sending smb: smb_len=%u\n", smb_buf_length
);
289 dump_smb(iov
[0].iov_base
, iov
[0].iov_len
);
291 /* cork the socket */
292 kernel_setsockopt(ssocket
, SOL_TCP
, TCP_CORK
,
293 (char *)&val
, sizeof(val
));
295 rc
= smb_send_kvec(server
, iov
, n_vec
, &sent
);
301 /* now walk the page array and send each page in it */
302 for (i
= 0; i
< rqst
->rq_npages
; i
++) {
305 cifs_rqst_page_to_kvec(rqst
, i
, &p_iov
);
306 rc
= smb_send_kvec(server
, &p_iov
, 1, &sent
);
307 kunmap(rqst
->rq_pages
[i
]);
317 kernel_setsockopt(ssocket
, SOL_TCP
, TCP_CORK
,
318 (char *)&val
, sizeof(val
));
320 if ((total_len
> 0) && (total_len
!= smb_buf_length
+ 4)) {
321 cifs_dbg(FYI
, "partial send (wanted=%u sent=%zu): terminating session\n",
322 smb_buf_length
+ 4, total_len
);
324 * If we have only sent part of an SMB then the next SMB could
325 * be taken as the remainder of this one. We need to kill the
326 * socket so the server throws away the partial SMB
328 server
->tcpStatus
= CifsNeedReconnect
;
331 if (rc
< 0 && rc
!= -EINTR
)
332 cifs_dbg(VFS
, "Error %d sending data on socket to server\n",
341 smb_sendv(struct TCP_Server_Info
*server
, struct kvec
*iov
, int n_vec
)
343 struct smb_rqst rqst
= { .rq_iov
= iov
,
346 return smb_send_rqst(server
, &rqst
);
350 smb_send(struct TCP_Server_Info
*server
, struct smb_hdr
*smb_buffer
,
351 unsigned int smb_buf_length
)
355 iov
.iov_base
= smb_buffer
;
356 iov
.iov_len
= smb_buf_length
+ 4;
358 return smb_sendv(server
, &iov
, 1);
362 wait_for_free_credits(struct TCP_Server_Info
*server
, const int timeout
,
367 spin_lock(&server
->req_lock
);
368 if (timeout
== CIFS_ASYNC_OP
) {
369 /* oplock breaks must not be held up */
372 spin_unlock(&server
->req_lock
);
378 spin_unlock(&server
->req_lock
);
379 cifs_num_waiters_inc(server
);
380 rc
= wait_event_killable(server
->request_q
,
381 has_credits(server
, credits
));
382 cifs_num_waiters_dec(server
);
385 spin_lock(&server
->req_lock
);
387 if (server
->tcpStatus
== CifsExiting
) {
388 spin_unlock(&server
->req_lock
);
393 * Can not count locking commands against total
394 * as they are allowed to block on server.
397 /* update # of requests on the wire to server */
398 if (timeout
!= CIFS_BLOCKING_OP
) {
402 spin_unlock(&server
->req_lock
);
410 wait_for_free_request(struct TCP_Server_Info
*server
, const int timeout
,
413 return wait_for_free_credits(server
, timeout
,
414 server
->ops
->get_credits_field(server
, optype
));
417 static int allocate_mid(struct cifs_ses
*ses
, struct smb_hdr
*in_buf
,
418 struct mid_q_entry
**ppmidQ
)
420 if (ses
->server
->tcpStatus
== CifsExiting
) {
424 if (ses
->server
->tcpStatus
== CifsNeedReconnect
) {
425 cifs_dbg(FYI
, "tcp session dead - return to caller to retry\n");
429 if (ses
->status
!= CifsGood
) {
430 /* check if SMB session is bad because we are setting it up */
431 if ((in_buf
->Command
!= SMB_COM_SESSION_SETUP_ANDX
) &&
432 (in_buf
->Command
!= SMB_COM_NEGOTIATE
))
434 /* else ok - we are setting up session */
436 *ppmidQ
= AllocMidQEntry(in_buf
, ses
->server
);
439 spin_lock(&GlobalMid_Lock
);
440 list_add_tail(&(*ppmidQ
)->qhead
, &ses
->server
->pending_mid_q
);
441 spin_unlock(&GlobalMid_Lock
);
446 wait_for_response(struct TCP_Server_Info
*server
, struct mid_q_entry
*midQ
)
450 error
= wait_event_freezekillable(server
->response_q
,
451 midQ
->mid_state
!= MID_REQUEST_SUBMITTED
);
459 cifs_setup_async_request(struct TCP_Server_Info
*server
, struct smb_rqst
*rqst
)
462 struct smb_hdr
*hdr
= (struct smb_hdr
*)rqst
->rq_iov
[0].iov_base
;
463 struct mid_q_entry
*mid
;
465 /* enable signing if server requires it */
466 if (server
->sec_mode
& (SECMODE_SIGN_REQUIRED
| SECMODE_SIGN_ENABLED
))
467 hdr
->Flags2
|= SMBFLG2_SECURITY_SIGNATURE
;
469 mid
= AllocMidQEntry(hdr
, server
);
471 return ERR_PTR(-ENOMEM
);
473 rc
= cifs_sign_rqst(rqst
, server
, &mid
->sequence_number
);
475 DeleteMidQEntry(mid
);
483 * Send a SMB request and set the callback function in the mid to handle
484 * the result. Caller is responsible for dealing with timeouts.
487 cifs_call_async(struct TCP_Server_Info
*server
, struct smb_rqst
*rqst
,
488 mid_receive_t
*receive
, mid_callback_t
*callback
,
489 void *cbdata
, const int flags
)
491 int rc
, timeout
, optype
;
492 struct mid_q_entry
*mid
;
494 timeout
= flags
& CIFS_TIMEOUT_MASK
;
495 optype
= flags
& CIFS_OP_MASK
;
497 rc
= wait_for_free_request(server
, timeout
, optype
);
501 mutex_lock(&server
->srv_mutex
);
502 mid
= server
->ops
->setup_async_request(server
, rqst
);
504 mutex_unlock(&server
->srv_mutex
);
505 add_credits(server
, 1, optype
);
506 wake_up(&server
->request_q
);
510 mid
->receive
= receive
;
511 mid
->callback
= callback
;
512 mid
->callback_data
= cbdata
;
513 mid
->mid_state
= MID_REQUEST_SUBMITTED
;
515 /* put it on the pending_mid_q */
516 spin_lock(&GlobalMid_Lock
);
517 list_add_tail(&mid
->qhead
, &server
->pending_mid_q
);
518 spin_unlock(&GlobalMid_Lock
);
521 cifs_in_send_inc(server
);
522 rc
= smb_send_rqst(server
, rqst
);
523 cifs_in_send_dec(server
);
524 cifs_save_when_sent(mid
);
527 server
->sequence_number
-= 2;
528 mutex_unlock(&server
->srv_mutex
);
533 cifs_delete_mid(mid
);
534 add_credits(server
, 1, optype
);
535 wake_up(&server
->request_q
);
541 * Send an SMB Request. No response info (other than return code)
542 * needs to be parsed.
544 * flags indicate the type of request buffer and how long to wait
545 * and whether to log NT STATUS code (error) before mapping it to POSIX error
549 SendReceiveNoRsp(const unsigned int xid
, struct cifs_ses
*ses
,
550 char *in_buf
, int flags
)
556 iov
[0].iov_base
= in_buf
;
557 iov
[0].iov_len
= get_rfc1002_length(in_buf
) + 4;
558 flags
|= CIFS_NO_RESP
;
559 rc
= SendReceive2(xid
, ses
, iov
, 1, &resp_buf_type
, flags
);
560 cifs_dbg(NOISY
, "SendRcvNoRsp flags %d rc %d\n", flags
, rc
);
566 cifs_sync_mid_result(struct mid_q_entry
*mid
, struct TCP_Server_Info
*server
)
570 cifs_dbg(FYI
, "%s: cmd=%d mid=%llu state=%d\n",
571 __func__
, le16_to_cpu(mid
->command
), mid
->mid
, mid
->mid_state
);
573 spin_lock(&GlobalMid_Lock
);
574 switch (mid
->mid_state
) {
575 case MID_RESPONSE_RECEIVED
:
576 spin_unlock(&GlobalMid_Lock
);
578 case MID_RETRY_NEEDED
:
581 case MID_RESPONSE_MALFORMED
:
588 list_del_init(&mid
->qhead
);
589 cifs_dbg(VFS
, "%s: invalid mid state mid=%llu state=%d\n",
590 __func__
, mid
->mid
, mid
->mid_state
);
593 spin_unlock(&GlobalMid_Lock
);
595 DeleteMidQEntry(mid
);
600 send_cancel(struct TCP_Server_Info
*server
, void *buf
, struct mid_q_entry
*mid
)
602 return server
->ops
->send_cancel
?
603 server
->ops
->send_cancel(server
, buf
, mid
) : 0;
607 cifs_check_receive(struct mid_q_entry
*mid
, struct TCP_Server_Info
*server
,
610 unsigned int len
= get_rfc1002_length(mid
->resp_buf
) + 4;
612 dump_smb(mid
->resp_buf
, min_t(u32
, 92, len
));
614 /* convert the length into a more usable form */
615 if (server
->sec_mode
& (SECMODE_SIGN_REQUIRED
| SECMODE_SIGN_ENABLED
)) {
618 struct smb_rqst rqst
= { .rq_iov
= &iov
,
621 iov
.iov_base
= mid
->resp_buf
;
623 /* FIXME: add code to kill session */
624 rc
= cifs_verify_signature(&rqst
, server
,
625 mid
->sequence_number
);
627 cifs_dbg(VFS
, "SMB signature verification returned error = %d\n",
631 /* BB special case reconnect tid and uid here? */
632 return map_smb_to_linux_error(mid
->resp_buf
, log_error
);
636 cifs_setup_request(struct cifs_ses
*ses
, struct smb_rqst
*rqst
)
639 struct smb_hdr
*hdr
= (struct smb_hdr
*)rqst
->rq_iov
[0].iov_base
;
640 struct mid_q_entry
*mid
;
642 rc
= allocate_mid(ses
, hdr
, &mid
);
645 rc
= cifs_sign_rqst(rqst
, ses
->server
, &mid
->sequence_number
);
647 cifs_delete_mid(mid
);
654 SendReceive2(const unsigned int xid
, struct cifs_ses
*ses
,
655 struct kvec
*iov
, int n_vec
, int *resp_buf_type
/* ret */,
660 struct mid_q_entry
*midQ
;
661 char *buf
= iov
[0].iov_base
;
662 unsigned int credits
= 1;
663 struct smb_rqst rqst
= { .rq_iov
= iov
,
666 timeout
= flags
& CIFS_TIMEOUT_MASK
;
667 optype
= flags
& CIFS_OP_MASK
;
669 *resp_buf_type
= CIFS_NO_BUFFER
; /* no response buf yet */
671 if ((ses
== NULL
) || (ses
->server
== NULL
)) {
672 cifs_small_buf_release(buf
);
673 cifs_dbg(VFS
, "Null session\n");
677 if (ses
->server
->tcpStatus
== CifsExiting
) {
678 cifs_small_buf_release(buf
);
683 * Ensure that we do not send more than 50 overlapping requests
684 * to the same server. We may make this configurable later or
688 rc
= wait_for_free_request(ses
->server
, timeout
, optype
);
690 cifs_small_buf_release(buf
);
695 * Make sure that we sign in the same order that we send on this socket
696 * and avoid races inside tcp sendmsg code that could cause corruption
700 mutex_lock(&ses
->server
->srv_mutex
);
702 midQ
= ses
->server
->ops
->setup_request(ses
, &rqst
);
704 mutex_unlock(&ses
->server
->srv_mutex
);
705 cifs_small_buf_release(buf
);
706 /* Update # of requests on wire to server */
707 add_credits(ses
->server
, 1, optype
);
708 return PTR_ERR(midQ
);
711 midQ
->mid_state
= MID_REQUEST_SUBMITTED
;
712 cifs_in_send_inc(ses
->server
);
713 rc
= smb_sendv(ses
->server
, iov
, n_vec
);
714 cifs_in_send_dec(ses
->server
);
715 cifs_save_when_sent(midQ
);
718 ses
->server
->sequence_number
-= 2;
719 mutex_unlock(&ses
->server
->srv_mutex
);
722 cifs_small_buf_release(buf
);
726 if (timeout
== CIFS_ASYNC_OP
) {
727 cifs_small_buf_release(buf
);
731 rc
= wait_for_response(ses
->server
, midQ
);
733 send_cancel(ses
->server
, buf
, midQ
);
734 spin_lock(&GlobalMid_Lock
);
735 if (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) {
736 midQ
->callback
= DeleteMidQEntry
;
737 spin_unlock(&GlobalMid_Lock
);
738 cifs_small_buf_release(buf
);
739 add_credits(ses
->server
, 1, optype
);
742 spin_unlock(&GlobalMid_Lock
);
745 cifs_small_buf_release(buf
);
747 rc
= cifs_sync_mid_result(midQ
, ses
->server
);
749 add_credits(ses
->server
, 1, optype
);
753 if (!midQ
->resp_buf
|| midQ
->mid_state
!= MID_RESPONSE_RECEIVED
) {
755 cifs_dbg(FYI
, "Bad MID state?\n");
759 buf
= (char *)midQ
->resp_buf
;
760 iov
[0].iov_base
= buf
;
761 iov
[0].iov_len
= get_rfc1002_length(buf
) + 4;
763 *resp_buf_type
= CIFS_LARGE_BUFFER
;
765 *resp_buf_type
= CIFS_SMALL_BUFFER
;
767 credits
= ses
->server
->ops
->get_credits(midQ
);
769 rc
= ses
->server
->ops
->check_receive(midQ
, ses
->server
,
770 flags
& CIFS_LOG_ERROR
);
772 /* mark it so buf will not be freed by cifs_delete_mid */
773 if ((flags
& CIFS_NO_RESP
) == 0)
774 midQ
->resp_buf
= NULL
;
776 cifs_delete_mid(midQ
);
777 add_credits(ses
->server
, credits
, optype
);
783 SendReceive(const unsigned int xid
, struct cifs_ses
*ses
,
784 struct smb_hdr
*in_buf
, struct smb_hdr
*out_buf
,
785 int *pbytes_returned
, const int timeout
)
788 struct mid_q_entry
*midQ
;
791 cifs_dbg(VFS
, "Null smb session\n");
794 if (ses
->server
== NULL
) {
795 cifs_dbg(VFS
, "Null tcp session\n");
799 if (ses
->server
->tcpStatus
== CifsExiting
)
802 /* Ensure that we do not send more than 50 overlapping requests
803 to the same server. We may make this configurable later or
806 if (be32_to_cpu(in_buf
->smb_buf_length
) > CIFSMaxBufSize
+
807 MAX_CIFS_HDR_SIZE
- 4) {
808 cifs_dbg(VFS
, "Illegal length, greater than maximum frame, %d\n",
809 be32_to_cpu(in_buf
->smb_buf_length
));
813 rc
= wait_for_free_request(ses
->server
, timeout
, 0);
817 /* make sure that we sign in the same order that we send on this socket
818 and avoid races inside tcp sendmsg code that could cause corruption
821 mutex_lock(&ses
->server
->srv_mutex
);
823 rc
= allocate_mid(ses
, in_buf
, &midQ
);
825 mutex_unlock(&ses
->server
->srv_mutex
);
826 /* Update # of requests on wire to server */
827 add_credits(ses
->server
, 1, 0);
831 rc
= cifs_sign_smb(in_buf
, ses
->server
, &midQ
->sequence_number
);
833 mutex_unlock(&ses
->server
->srv_mutex
);
837 midQ
->mid_state
= MID_REQUEST_SUBMITTED
;
839 cifs_in_send_inc(ses
->server
);
840 rc
= smb_send(ses
->server
, in_buf
, be32_to_cpu(in_buf
->smb_buf_length
));
841 cifs_in_send_dec(ses
->server
);
842 cifs_save_when_sent(midQ
);
845 ses
->server
->sequence_number
-= 2;
847 mutex_unlock(&ses
->server
->srv_mutex
);
852 if (timeout
== CIFS_ASYNC_OP
)
855 rc
= wait_for_response(ses
->server
, midQ
);
857 send_cancel(ses
->server
, in_buf
, midQ
);
858 spin_lock(&GlobalMid_Lock
);
859 if (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) {
860 /* no longer considered to be "in-flight" */
861 midQ
->callback
= DeleteMidQEntry
;
862 spin_unlock(&GlobalMid_Lock
);
863 add_credits(ses
->server
, 1, 0);
866 spin_unlock(&GlobalMid_Lock
);
869 rc
= cifs_sync_mid_result(midQ
, ses
->server
);
871 add_credits(ses
->server
, 1, 0);
875 if (!midQ
->resp_buf
|| !out_buf
||
876 midQ
->mid_state
!= MID_RESPONSE_RECEIVED
) {
878 cifs_dbg(VFS
, "Bad MID state?\n");
882 *pbytes_returned
= get_rfc1002_length(midQ
->resp_buf
);
883 memcpy(out_buf
, midQ
->resp_buf
, *pbytes_returned
+ 4);
884 rc
= cifs_check_receive(midQ
, ses
->server
, 0);
886 cifs_delete_mid(midQ
);
887 add_credits(ses
->server
, 1, 0);
892 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
893 blocking lock to return. */
896 send_lock_cancel(const unsigned int xid
, struct cifs_tcon
*tcon
,
897 struct smb_hdr
*in_buf
,
898 struct smb_hdr
*out_buf
)
901 struct cifs_ses
*ses
= tcon
->ses
;
902 LOCK_REQ
*pSMB
= (LOCK_REQ
*)in_buf
;
904 /* We just modify the current in_buf to change
905 the type of lock from LOCKING_ANDX_SHARED_LOCK
906 or LOCKING_ANDX_EXCLUSIVE_LOCK to
907 LOCKING_ANDX_CANCEL_LOCK. */
909 pSMB
->LockType
= LOCKING_ANDX_CANCEL_LOCK
|LOCKING_ANDX_LARGE_FILES
;
911 pSMB
->hdr
.Mid
= get_next_mid(ses
->server
);
913 return SendReceive(xid
, ses
, in_buf
, out_buf
,
918 SendReceiveBlockingLock(const unsigned int xid
, struct cifs_tcon
*tcon
,
919 struct smb_hdr
*in_buf
, struct smb_hdr
*out_buf
,
920 int *pbytes_returned
)
924 struct mid_q_entry
*midQ
;
925 struct cifs_ses
*ses
;
927 if (tcon
== NULL
|| tcon
->ses
== NULL
) {
928 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 (be32_to_cpu(in_buf
->smb_buf_length
) > CIFSMaxBufSize
+
946 MAX_CIFS_HDR_SIZE
- 4) {
947 cifs_dbg(VFS
, "Illegal length, greater than maximum frame, %d\n",
948 be32_to_cpu(in_buf
->smb_buf_length
));
952 rc
= wait_for_free_request(ses
->server
, CIFS_BLOCKING_OP
, 0);
956 /* make sure that we sign in the same order that we send on this socket
957 and avoid races inside tcp sendmsg code that could cause corruption
960 mutex_lock(&ses
->server
->srv_mutex
);
962 rc
= allocate_mid(ses
, in_buf
, &midQ
);
964 mutex_unlock(&ses
->server
->srv_mutex
);
968 rc
= cifs_sign_smb(in_buf
, ses
->server
, &midQ
->sequence_number
);
970 cifs_delete_mid(midQ
);
971 mutex_unlock(&ses
->server
->srv_mutex
);
975 midQ
->mid_state
= MID_REQUEST_SUBMITTED
;
976 cifs_in_send_inc(ses
->server
);
977 rc
= smb_send(ses
->server
, in_buf
, be32_to_cpu(in_buf
->smb_buf_length
));
978 cifs_in_send_dec(ses
->server
);
979 cifs_save_when_sent(midQ
);
982 ses
->server
->sequence_number
-= 2;
984 mutex_unlock(&ses
->server
->srv_mutex
);
987 cifs_delete_mid(midQ
);
991 /* Wait for a reply - allow signals to interrupt. */
992 rc
= wait_event_interruptible(ses
->server
->response_q
,
993 (!(midQ
->mid_state
== MID_REQUEST_SUBMITTED
)) ||
994 ((ses
->server
->tcpStatus
!= CifsGood
) &&
995 (ses
->server
->tcpStatus
!= CifsNew
)));
997 /* Were we interrupted by a signal ? */
998 if ((rc
== -ERESTARTSYS
) &&
999 (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) &&
1000 ((ses
->server
->tcpStatus
== CifsGood
) ||
1001 (ses
->server
->tcpStatus
== CifsNew
))) {
1003 if (in_buf
->Command
== SMB_COM_TRANSACTION2
) {
1004 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1005 blocking lock to return. */
1006 rc
= send_cancel(ses
->server
, in_buf
, midQ
);
1008 cifs_delete_mid(midQ
);
1012 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1013 to cause the blocking lock to return. */
1015 rc
= send_lock_cancel(xid
, tcon
, in_buf
, out_buf
);
1017 /* If we get -ENOLCK back the lock may have
1018 already been removed. Don't exit in this case. */
1019 if (rc
&& rc
!= -ENOLCK
) {
1020 cifs_delete_mid(midQ
);
1025 rc
= wait_for_response(ses
->server
, midQ
);
1027 send_cancel(ses
->server
, in_buf
, midQ
);
1028 spin_lock(&GlobalMid_Lock
);
1029 if (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) {
1030 /* no longer considered to be "in-flight" */
1031 midQ
->callback
= DeleteMidQEntry
;
1032 spin_unlock(&GlobalMid_Lock
);
1035 spin_unlock(&GlobalMid_Lock
);
1038 /* We got the response - restart system call. */
1042 rc
= cifs_sync_mid_result(midQ
, ses
->server
);
1046 /* rcvd frame is ok */
1047 if (out_buf
== NULL
|| midQ
->mid_state
!= MID_RESPONSE_RECEIVED
) {
1049 cifs_dbg(VFS
, "Bad MID state?\n");
1053 *pbytes_returned
= get_rfc1002_length(midQ
->resp_buf
);
1054 memcpy(out_buf
, midQ
->resp_buf
, *pbytes_returned
+ 4);
1055 rc
= cifs_check_receive(midQ
, ses
->server
, 0);
1057 cifs_delete_mid(midQ
);
1058 if (rstart
&& rc
== -EACCES
)
1059 return -ERESTARTSYS
;