4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 * Jeremy Allison (jra@samba.org) 2006.
8 * This library is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU Lesser General Public License as published
10 * by the Free Software Foundation; either version 2.1 of the License, or
11 * (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
16 * the GNU Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public License
19 * along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include <linux/list.h>
25 #include <linux/gfp.h>
26 #include <linux/wait.h>
27 #include <linux/net.h>
28 #include <linux/delay.h>
29 #include <linux/freezer.h>
30 #include <linux/tcp.h>
31 #include <linux/bvec.h>
32 #include <linux/highmem.h>
33 #include <linux/uaccess.h>
34 #include <asm/processor.h>
35 #include <linux/mempool.h>
38 #include "cifsproto.h"
39 #include "cifs_debug.h"
42 cifs_wake_up_task(struct mid_q_entry
*mid
)
44 wake_up_process(mid
->callback_data
);
48 AllocMidQEntry(const struct smb_hdr
*smb_buffer
, struct TCP_Server_Info
*server
)
50 struct mid_q_entry
*temp
;
53 cifs_dbg(VFS
, "Null TCP session in AllocMidQEntry\n");
57 temp
= mempool_alloc(cifs_mid_poolp
, GFP_NOFS
);
61 memset(temp
, 0, sizeof(struct mid_q_entry
));
62 temp
->mid
= get_mid(smb_buffer
);
63 temp
->pid
= current
->pid
;
64 temp
->command
= cpu_to_le16(smb_buffer
->Command
);
65 cifs_dbg(FYI
, "For smb_command %d\n", smb_buffer
->Command
);
66 /* do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
67 /* when mid allocated can be before when sent */
68 temp
->when_alloc
= jiffies
;
69 temp
->server
= server
;
72 * The default is for the mid to be synchronous, so the
73 * default callback just wakes up the current task.
75 temp
->callback
= cifs_wake_up_task
;
76 temp
->callback_data
= current
;
79 atomic_inc(&midCount
);
80 temp
->mid_state
= MID_REQUEST_ALLOCATED
;
85 DeleteMidQEntry(struct mid_q_entry
*midEntry
)
87 #ifdef CONFIG_CIFS_STATS2
88 __le16 command
= midEntry
->server
->vals
->lock_cmd
;
91 midEntry
->mid_state
= MID_FREE
;
92 atomic_dec(&midCount
);
93 if (midEntry
->large_buf
)
94 cifs_buf_release(midEntry
->resp_buf
);
96 cifs_small_buf_release(midEntry
->resp_buf
);
97 #ifdef CONFIG_CIFS_STATS2
99 /* commands taking longer than one second are indications that
100 something is wrong, unless it is quite a slow link or server */
101 if ((now
- midEntry
->when_alloc
) > HZ
) {
102 if ((cifsFYI
& CIFS_TIMER
) && (midEntry
->command
!= command
)) {
103 pr_debug(" CIFS slow rsp: cmd %d mid %llu",
104 midEntry
->command
, midEntry
->mid
);
105 pr_info(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
106 now
- midEntry
->when_alloc
,
107 now
- midEntry
->when_sent
,
108 now
- midEntry
->when_received
);
112 mempool_free(midEntry
, cifs_mid_poolp
);
116 cifs_delete_mid(struct mid_q_entry
*mid
)
118 spin_lock(&GlobalMid_Lock
);
119 list_del(&mid
->qhead
);
120 spin_unlock(&GlobalMid_Lock
);
122 DeleteMidQEntry(mid
);
126 * smb_send_kvec - send an array of kvecs to the server
127 * @server: Server to send the data to
128 * @smb_msg: Message to send
129 * @sent: amount of data sent on socket is stored here
131 * Our basic "send data to server" function. Should be called with srv_mutex
132 * held. The caller is responsible for handling the results.
135 smb_send_kvec(struct TCP_Server_Info
*server
, struct msghdr
*smb_msg
,
140 struct socket
*ssocket
= server
->ssocket
;
144 smb_msg
->msg_name
= (struct sockaddr
*) &server
->dstaddr
;
145 smb_msg
->msg_namelen
= sizeof(struct sockaddr
);
146 smb_msg
->msg_control
= NULL
;
147 smb_msg
->msg_controllen
= 0;
148 if (server
->noblocksnd
)
149 smb_msg
->msg_flags
= MSG_DONTWAIT
+ MSG_NOSIGNAL
;
151 smb_msg
->msg_flags
= MSG_NOSIGNAL
;
153 while (msg_data_left(smb_msg
)) {
155 * If blocking send, we try 3 times, since each can block
156 * for 5 seconds. For nonblocking we have to try more
157 * but wait increasing amounts of time allowing time for
158 * socket to clear. The overall time we wait in either
159 * case to send on the socket is about 15 seconds.
160 * Similarly we wait for 15 seconds for a response from
161 * the server in SendReceive[2] for the server to send
162 * a response back for most types of requests (except
163 * SMB Write past end of file which can be slow, and
164 * blocking lock operations). NFS waits slightly longer
165 * than CIFS, but this can make it take longer for
166 * nonresponsive servers to be detected and 15 seconds
167 * is more than enough time for modern networks to
168 * send a packet. In most cases if we fail to send
169 * after the retries we will kill the socket and
170 * reconnect which may clear the network problem.
172 rc
= sock_sendmsg(ssocket
, smb_msg
);
176 (!server
->noblocksnd
&& (retries
> 2))) {
177 cifs_dbg(VFS
, "sends on sock %p stuck for 15 seconds\n",
181 msleep(1 << retries
);
189 /* should never happen, letting socket clear before
190 retrying is our only obvious option here */
191 cifs_dbg(VFS
, "tcp sent no data\n");
196 /* send was at least partially successful */
198 retries
= 0; /* in case we get ENOSPC on the next send */
204 rqst_len(struct smb_rqst
*rqst
)
207 struct kvec
*iov
= rqst
->rq_iov
;
208 unsigned long buflen
= 0;
210 /* total up iov array first */
211 for (i
= 0; i
< rqst
->rq_nvec
; i
++)
212 buflen
+= iov
[i
].iov_len
;
214 /* add in the page array if there is one */
215 if (rqst
->rq_npages
) {
216 buflen
+= rqst
->rq_pagesz
* (rqst
->rq_npages
- 1);
217 buflen
+= rqst
->rq_tailsz
;
224 smb_send_rqst(struct TCP_Server_Info
*server
, struct smb_rqst
*rqst
)
227 struct kvec
*iov
= rqst
->rq_iov
;
228 int n_vec
= rqst
->rq_nvec
;
229 unsigned int smb_buf_length
= get_rfc1002_length(iov
[0].iov_base
);
230 unsigned long send_length
;
232 size_t total_len
= 0, sent
, size
;
233 struct socket
*ssocket
= server
->ssocket
;
234 struct msghdr smb_msg
;
240 /* sanity check send length */
241 send_length
= rqst_len(rqst
);
242 if (send_length
!= smb_buf_length
+ 4) {
243 WARN(1, "Send length mismatch(send_length=%lu smb_buf_length=%u)\n",
244 send_length
, smb_buf_length
);
251 cifs_dbg(FYI
, "Sending smb: smb_len=%u\n", smb_buf_length
);
252 dump_smb(iov
[0].iov_base
, iov
[0].iov_len
);
253 dump_smb(iov
[1].iov_base
, iov
[1].iov_len
);
255 /* cork the socket */
256 kernel_setsockopt(ssocket
, SOL_TCP
, TCP_CORK
,
257 (char *)&val
, sizeof(val
));
260 for (i
= 0; i
< n_vec
; i
++)
261 size
+= iov
[i
].iov_len
;
263 iov_iter_kvec(&smb_msg
.msg_iter
, WRITE
| ITER_KVEC
, iov
, n_vec
, size
);
265 rc
= smb_send_kvec(server
, &smb_msg
, &sent
);
271 /* now walk the page array and send each page in it */
272 for (i
= 0; i
< rqst
->rq_npages
; i
++) {
273 size_t len
= i
== rqst
->rq_npages
- 1
276 struct bio_vec bvec
= {
277 .bv_page
= rqst
->rq_pages
[i
],
280 iov_iter_bvec(&smb_msg
.msg_iter
, WRITE
| ITER_BVEC
,
282 rc
= smb_send_kvec(server
, &smb_msg
, &sent
);
292 kernel_setsockopt(ssocket
, SOL_TCP
, TCP_CORK
,
293 (char *)&val
, sizeof(val
));
295 if ((total_len
> 0) && (total_len
!= smb_buf_length
+ 4)) {
296 cifs_dbg(FYI
, "partial send (wanted=%u sent=%zu): terminating session\n",
297 smb_buf_length
+ 4, total_len
);
299 * If we have only sent part of an SMB then the next SMB could
300 * be taken as the remainder of this one. We need to kill the
301 * socket so the server throws away the partial SMB
303 server
->tcpStatus
= CifsNeedReconnect
;
306 if (rc
< 0 && rc
!= -EINTR
)
307 cifs_dbg(VFS
, "Error %d sending data on socket to server\n",
316 smb_sendv(struct TCP_Server_Info
*server
, struct kvec
*iov
, int n_vec
)
318 struct smb_rqst rqst
= { .rq_iov
= iov
,
321 return smb_send_rqst(server
, &rqst
);
325 smb_send(struct TCP_Server_Info
*server
, struct smb_hdr
*smb_buffer
,
326 unsigned int smb_buf_length
)
330 iov
[0].iov_base
= smb_buffer
;
332 iov
[1].iov_base
= (char *)smb_buffer
+ 4;
333 iov
[1].iov_len
= smb_buf_length
;
335 return smb_sendv(server
, iov
, 2);
339 wait_for_free_credits(struct TCP_Server_Info
*server
, const int timeout
,
344 spin_lock(&server
->req_lock
);
345 if (timeout
== CIFS_ASYNC_OP
) {
346 /* oplock breaks must not be held up */
349 spin_unlock(&server
->req_lock
);
355 spin_unlock(&server
->req_lock
);
356 cifs_num_waiters_inc(server
);
357 rc
= wait_event_killable(server
->request_q
,
358 has_credits(server
, credits
));
359 cifs_num_waiters_dec(server
);
362 spin_lock(&server
->req_lock
);
364 if (server
->tcpStatus
== CifsExiting
) {
365 spin_unlock(&server
->req_lock
);
370 * Can not count locking commands against total
371 * as they are allowed to block on server.
374 /* update # of requests on the wire to server */
375 if (timeout
!= CIFS_BLOCKING_OP
) {
379 spin_unlock(&server
->req_lock
);
387 wait_for_free_request(struct TCP_Server_Info
*server
, const int timeout
,
392 val
= server
->ops
->get_credits_field(server
, optype
);
393 /* Since an echo is already inflight, no need to wait to send another */
394 if (*val
<= 0 && optype
== CIFS_ECHO_OP
)
396 return wait_for_free_credits(server
, timeout
, val
);
400 cifs_wait_mtu_credits(struct TCP_Server_Info
*server
, unsigned int size
,
401 unsigned int *num
, unsigned int *credits
)
408 static int allocate_mid(struct cifs_ses
*ses
, struct smb_hdr
*in_buf
,
409 struct mid_q_entry
**ppmidQ
)
411 if (ses
->server
->tcpStatus
== CifsExiting
) {
415 if (ses
->server
->tcpStatus
== CifsNeedReconnect
) {
416 cifs_dbg(FYI
, "tcp session dead - return to caller to retry\n");
420 if (ses
->status
== CifsNew
) {
421 if ((in_buf
->Command
!= SMB_COM_SESSION_SETUP_ANDX
) &&
422 (in_buf
->Command
!= SMB_COM_NEGOTIATE
))
424 /* else ok - we are setting up session */
427 if (ses
->status
== CifsExiting
) {
428 /* check if SMB session is bad because we are setting it up */
429 if (in_buf
->Command
!= SMB_COM_LOGOFF_ANDX
)
431 /* else ok - we are shutting down session */
434 *ppmidQ
= AllocMidQEntry(in_buf
, ses
->server
);
437 spin_lock(&GlobalMid_Lock
);
438 list_add_tail(&(*ppmidQ
)->qhead
, &ses
->server
->pending_mid_q
);
439 spin_unlock(&GlobalMid_Lock
);
444 wait_for_response(struct TCP_Server_Info
*server
, struct mid_q_entry
*midQ
)
448 error
= wait_event_freezekillable_unsafe(server
->response_q
,
449 midQ
->mid_state
!= MID_REQUEST_SUBMITTED
);
457 cifs_setup_async_request(struct TCP_Server_Info
*server
, struct smb_rqst
*rqst
)
460 struct smb_hdr
*hdr
= (struct smb_hdr
*)rqst
->rq_iov
[0].iov_base
;
461 struct mid_q_entry
*mid
;
463 if (rqst
->rq_iov
[0].iov_len
!= 4 ||
464 rqst
->rq_iov
[0].iov_base
+ 4 != rqst
->rq_iov
[1].iov_base
)
465 return ERR_PTR(-EIO
);
467 /* enable signing if server requires it */
469 hdr
->Flags2
|= SMBFLG2_SECURITY_SIGNATURE
;
471 mid
= AllocMidQEntry(hdr
, server
);
473 return ERR_PTR(-ENOMEM
);
475 rc
= cifs_sign_rqst(rqst
, server
, &mid
->sequence_number
);
477 DeleteMidQEntry(mid
);
485 * Send a SMB request and set the callback function in the mid to handle
486 * the result. Caller is responsible for dealing with timeouts.
489 cifs_call_async(struct TCP_Server_Info
*server
, struct smb_rqst
*rqst
,
490 mid_receive_t
*receive
, mid_callback_t
*callback
, void *cbdata
,
493 int rc
, timeout
, optype
;
494 struct mid_q_entry
*mid
;
495 unsigned int credits
= 0;
497 timeout
= flags
& CIFS_TIMEOUT_MASK
;
498 optype
= flags
& CIFS_OP_MASK
;
500 if ((flags
& CIFS_HAS_CREDITS
) == 0) {
501 rc
= wait_for_free_request(server
, timeout
, optype
);
507 mutex_lock(&server
->srv_mutex
);
508 mid
= server
->ops
->setup_async_request(server
, rqst
);
510 mutex_unlock(&server
->srv_mutex
);
511 add_credits_and_wake_if(server
, credits
, optype
);
515 mid
->receive
= receive
;
516 mid
->callback
= callback
;
517 mid
->callback_data
= cbdata
;
518 mid
->mid_state
= MID_REQUEST_SUBMITTED
;
520 /* put it on the pending_mid_q */
521 spin_lock(&GlobalMid_Lock
);
522 list_add_tail(&mid
->qhead
, &server
->pending_mid_q
);
523 spin_unlock(&GlobalMid_Lock
);
526 cifs_in_send_inc(server
);
527 rc
= smb_send_rqst(server
, rqst
);
528 cifs_in_send_dec(server
);
529 cifs_save_when_sent(mid
);
532 server
->sequence_number
-= 2;
533 cifs_delete_mid(mid
);
536 mutex_unlock(&server
->srv_mutex
);
541 add_credits_and_wake_if(server
, credits
, optype
);
547 * Send an SMB Request. No response info (other than return code)
548 * needs to be parsed.
550 * flags indicate the type of request buffer and how long to wait
551 * and whether to log NT STATUS code (error) before mapping it to POSIX error
555 SendReceiveNoRsp(const unsigned int xid
, struct cifs_ses
*ses
,
556 char *in_buf
, int flags
)
563 iov
[0].iov_base
= in_buf
;
564 iov
[0].iov_len
= get_rfc1002_length(in_buf
) + 4;
565 flags
|= CIFS_NO_RESP
;
566 rc
= SendReceive2(xid
, ses
, iov
, 1, &resp_buf_type
, flags
, &rsp_iov
);
567 cifs_dbg(NOISY
, "SendRcvNoRsp flags %d rc %d\n", flags
, rc
);
573 cifs_sync_mid_result(struct mid_q_entry
*mid
, struct TCP_Server_Info
*server
)
577 cifs_dbg(FYI
, "%s: cmd=%d mid=%llu state=%d\n",
578 __func__
, le16_to_cpu(mid
->command
), mid
->mid
, mid
->mid_state
);
580 spin_lock(&GlobalMid_Lock
);
581 switch (mid
->mid_state
) {
582 case MID_RESPONSE_RECEIVED
:
583 spin_unlock(&GlobalMid_Lock
);
585 case MID_RETRY_NEEDED
:
588 case MID_RESPONSE_MALFORMED
:
595 list_del_init(&mid
->qhead
);
596 cifs_dbg(VFS
, "%s: invalid mid state mid=%llu state=%d\n",
597 __func__
, mid
->mid
, mid
->mid_state
);
600 spin_unlock(&GlobalMid_Lock
);
602 mutex_lock(&server
->srv_mutex
);
603 DeleteMidQEntry(mid
);
604 mutex_unlock(&server
->srv_mutex
);
609 send_cancel(struct TCP_Server_Info
*server
, struct smb_rqst
*rqst
,
610 struct mid_q_entry
*mid
)
612 return server
->ops
->send_cancel
?
613 server
->ops
->send_cancel(server
, rqst
, mid
) : 0;
617 cifs_check_receive(struct mid_q_entry
*mid
, struct TCP_Server_Info
*server
,
620 unsigned int len
= get_rfc1002_length(mid
->resp_buf
) + 4;
622 dump_smb(mid
->resp_buf
, min_t(u32
, 92, len
));
624 /* convert the length into a more usable form */
628 struct smb_rqst rqst
= { .rq_iov
= iov
,
631 iov
[0].iov_base
= mid
->resp_buf
;
633 iov
[1].iov_base
= (char *)mid
->resp_buf
+ 4;
634 iov
[1].iov_len
= len
- 4;
635 /* FIXME: add code to kill session */
636 rc
= cifs_verify_signature(&rqst
, server
,
637 mid
->sequence_number
);
639 cifs_dbg(VFS
, "SMB signature verification returned error = %d\n",
643 /* BB special case reconnect tid and uid here? */
644 return map_smb_to_linux_error(mid
->resp_buf
, log_error
);
648 cifs_setup_request(struct cifs_ses
*ses
, struct smb_rqst
*rqst
)
651 struct smb_hdr
*hdr
= (struct smb_hdr
*)rqst
->rq_iov
[0].iov_base
;
652 struct mid_q_entry
*mid
;
654 if (rqst
->rq_iov
[0].iov_len
!= 4 ||
655 rqst
->rq_iov
[0].iov_base
+ 4 != rqst
->rq_iov
[1].iov_base
)
656 return ERR_PTR(-EIO
);
658 rc
= allocate_mid(ses
, hdr
, &mid
);
661 rc
= cifs_sign_rqst(rqst
, ses
->server
, &mid
->sequence_number
);
663 cifs_delete_mid(mid
);
670 cifs_send_recv(const unsigned int xid
, struct cifs_ses
*ses
,
671 struct smb_rqst
*rqst
, int *resp_buf_type
, const int flags
,
672 struct kvec
*resp_iov
)
676 struct mid_q_entry
*midQ
;
677 unsigned int credits
= 1;
680 timeout
= flags
& CIFS_TIMEOUT_MASK
;
681 optype
= flags
& CIFS_OP_MASK
;
683 *resp_buf_type
= CIFS_NO_BUFFER
; /* no response buf yet */
685 if ((ses
== NULL
) || (ses
->server
== NULL
)) {
686 cifs_dbg(VFS
, "Null session\n");
690 if (ses
->server
->tcpStatus
== CifsExiting
)
694 * Ensure that we do not send more than 50 overlapping requests
695 * to the same server. We may make this configurable later or
699 rc
= wait_for_free_request(ses
->server
, timeout
, optype
);
704 * Make sure that we sign in the same order that we send on this socket
705 * and avoid races inside tcp sendmsg code that could cause corruption
709 mutex_lock(&ses
->server
->srv_mutex
);
711 midQ
= ses
->server
->ops
->setup_request(ses
, rqst
);
713 mutex_unlock(&ses
->server
->srv_mutex
);
714 /* Update # of requests on wire to server */
715 add_credits(ses
->server
, 1, optype
);
716 return PTR_ERR(midQ
);
719 midQ
->mid_state
= MID_REQUEST_SUBMITTED
;
720 cifs_in_send_inc(ses
->server
);
721 rc
= smb_send_rqst(ses
->server
, rqst
);
722 cifs_in_send_dec(ses
->server
);
723 cifs_save_when_sent(midQ
);
726 ses
->server
->sequence_number
-= 2;
727 mutex_unlock(&ses
->server
->srv_mutex
);
732 if (timeout
== CIFS_ASYNC_OP
)
735 rc
= wait_for_response(ses
->server
, midQ
);
737 send_cancel(ses
->server
, rqst
, midQ
);
738 spin_lock(&GlobalMid_Lock
);
739 if (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) {
740 midQ
->callback
= DeleteMidQEntry
;
741 spin_unlock(&GlobalMid_Lock
);
742 add_credits(ses
->server
, 1, optype
);
745 spin_unlock(&GlobalMid_Lock
);
748 rc
= cifs_sync_mid_result(midQ
, ses
->server
);
750 add_credits(ses
->server
, 1, optype
);
754 if (!midQ
->resp_buf
|| midQ
->mid_state
!= MID_RESPONSE_RECEIVED
) {
756 cifs_dbg(FYI
, "Bad MID state?\n");
760 buf
= (char *)midQ
->resp_buf
;
761 resp_iov
->iov_base
= buf
;
762 resp_iov
->iov_len
= get_rfc1002_length(buf
) + 4;
764 *resp_buf_type
= CIFS_LARGE_BUFFER
;
766 *resp_buf_type
= CIFS_SMALL_BUFFER
;
768 credits
= ses
->server
->ops
->get_credits(midQ
);
770 rc
= ses
->server
->ops
->check_receive(midQ
, ses
->server
,
771 flags
& CIFS_LOG_ERROR
);
773 /* mark it so buf will not be freed by cifs_delete_mid */
774 if ((flags
& CIFS_NO_RESP
) == 0)
775 midQ
->resp_buf
= NULL
;
777 cifs_delete_mid(midQ
);
778 add_credits(ses
->server
, credits
, optype
);
784 SendReceive2(const unsigned int xid
, struct cifs_ses
*ses
,
785 struct kvec
*iov
, int n_vec
, int *resp_buf_type
/* ret */,
786 const int flags
, struct kvec
*resp_iov
)
788 struct smb_rqst rqst
;
789 struct kvec
*new_iov
;
792 new_iov
= kmalloc(sizeof(struct kvec
) * (n_vec
+ 1), GFP_KERNEL
);
796 /* 1st iov is a RFC1001 length followed by the rest of the packet */
797 memcpy(new_iov
+ 1, iov
, (sizeof(struct kvec
) * n_vec
));
799 new_iov
[0].iov_base
= new_iov
[1].iov_base
;
800 new_iov
[0].iov_len
= 4;
801 new_iov
[1].iov_base
+= 4;
802 new_iov
[1].iov_len
-= 4;
804 memset(&rqst
, 0, sizeof(struct smb_rqst
));
805 rqst
.rq_iov
= new_iov
;
806 rqst
.rq_nvec
= n_vec
+ 1;
808 rc
= cifs_send_recv(xid
, ses
, &rqst
, resp_buf_type
, flags
, resp_iov
);
814 SendReceive(const unsigned int xid
, struct cifs_ses
*ses
,
815 struct smb_hdr
*in_buf
, struct smb_hdr
*out_buf
,
816 int *pbytes_returned
, const int timeout
)
819 struct mid_q_entry
*midQ
;
820 unsigned int len
= be32_to_cpu(in_buf
->smb_buf_length
);
821 struct kvec iov
= { .iov_base
= in_buf
, .iov_len
= len
};
822 struct smb_rqst rqst
= { .rq_iov
= &iov
, .rq_nvec
= 1 };
825 cifs_dbg(VFS
, "Null smb session\n");
828 if (ses
->server
== NULL
) {
829 cifs_dbg(VFS
, "Null tcp session\n");
833 if (ses
->server
->tcpStatus
== CifsExiting
)
836 /* Ensure that we do not send more than 50 overlapping requests
837 to the same server. We may make this configurable later or
840 if (len
> CIFSMaxBufSize
+ MAX_CIFS_HDR_SIZE
- 4) {
841 cifs_dbg(VFS
, "Illegal length, greater than maximum frame, %d\n",
846 rc
= wait_for_free_request(ses
->server
, timeout
, 0);
850 /* make sure that we sign in the same order that we send on this socket
851 and avoid races inside tcp sendmsg code that could cause corruption
854 mutex_lock(&ses
->server
->srv_mutex
);
856 rc
= allocate_mid(ses
, in_buf
, &midQ
);
858 mutex_unlock(&ses
->server
->srv_mutex
);
859 /* Update # of requests on wire to server */
860 add_credits(ses
->server
, 1, 0);
864 rc
= cifs_sign_smb(in_buf
, ses
->server
, &midQ
->sequence_number
);
866 mutex_unlock(&ses
->server
->srv_mutex
);
870 midQ
->mid_state
= MID_REQUEST_SUBMITTED
;
872 cifs_in_send_inc(ses
->server
);
873 rc
= smb_send(ses
->server
, in_buf
, len
);
874 cifs_in_send_dec(ses
->server
);
875 cifs_save_when_sent(midQ
);
878 ses
->server
->sequence_number
-= 2;
880 mutex_unlock(&ses
->server
->srv_mutex
);
885 if (timeout
== CIFS_ASYNC_OP
)
888 rc
= wait_for_response(ses
->server
, midQ
);
890 send_cancel(ses
->server
, &rqst
, midQ
);
891 spin_lock(&GlobalMid_Lock
);
892 if (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) {
893 /* no longer considered to be "in-flight" */
894 midQ
->callback
= DeleteMidQEntry
;
895 spin_unlock(&GlobalMid_Lock
);
896 add_credits(ses
->server
, 1, 0);
899 spin_unlock(&GlobalMid_Lock
);
902 rc
= cifs_sync_mid_result(midQ
, ses
->server
);
904 add_credits(ses
->server
, 1, 0);
908 if (!midQ
->resp_buf
|| !out_buf
||
909 midQ
->mid_state
!= MID_RESPONSE_RECEIVED
) {
911 cifs_dbg(VFS
, "Bad MID state?\n");
915 *pbytes_returned
= get_rfc1002_length(midQ
->resp_buf
);
916 memcpy(out_buf
, midQ
->resp_buf
, *pbytes_returned
+ 4);
917 rc
= cifs_check_receive(midQ
, ses
->server
, 0);
919 cifs_delete_mid(midQ
);
920 add_credits(ses
->server
, 1, 0);
925 /* We send a LOCKINGX_CANCEL_LOCK to cause the Windows
926 blocking lock to return. */
929 send_lock_cancel(const unsigned int xid
, struct cifs_tcon
*tcon
,
930 struct smb_hdr
*in_buf
,
931 struct smb_hdr
*out_buf
)
934 struct cifs_ses
*ses
= tcon
->ses
;
935 LOCK_REQ
*pSMB
= (LOCK_REQ
*)in_buf
;
937 /* We just modify the current in_buf to change
938 the type of lock from LOCKING_ANDX_SHARED_LOCK
939 or LOCKING_ANDX_EXCLUSIVE_LOCK to
940 LOCKING_ANDX_CANCEL_LOCK. */
942 pSMB
->LockType
= LOCKING_ANDX_CANCEL_LOCK
|LOCKING_ANDX_LARGE_FILES
;
944 pSMB
->hdr
.Mid
= get_next_mid(ses
->server
);
946 return SendReceive(xid
, ses
, in_buf
, out_buf
,
951 SendReceiveBlockingLock(const unsigned int xid
, struct cifs_tcon
*tcon
,
952 struct smb_hdr
*in_buf
, struct smb_hdr
*out_buf
,
953 int *pbytes_returned
)
957 struct mid_q_entry
*midQ
;
958 struct cifs_ses
*ses
;
959 unsigned int len
= be32_to_cpu(in_buf
->smb_buf_length
);
960 struct kvec iov
= { .iov_base
= in_buf
, .iov_len
= len
};
961 struct smb_rqst rqst
= { .rq_iov
= &iov
, .rq_nvec
= 1 };
963 if (tcon
== NULL
|| tcon
->ses
== NULL
) {
964 cifs_dbg(VFS
, "Null smb session\n");
969 if (ses
->server
== NULL
) {
970 cifs_dbg(VFS
, "Null tcp session\n");
974 if (ses
->server
->tcpStatus
== CifsExiting
)
977 /* Ensure that we do not send more than 50 overlapping requests
978 to the same server. We may make this configurable later or
981 if (len
> CIFSMaxBufSize
+ MAX_CIFS_HDR_SIZE
- 4) {
982 cifs_dbg(VFS
, "Illegal length, greater than maximum frame, %d\n",
987 rc
= wait_for_free_request(ses
->server
, CIFS_BLOCKING_OP
, 0);
991 /* make sure that we sign in the same order that we send on this socket
992 and avoid races inside tcp sendmsg code that could cause corruption
995 mutex_lock(&ses
->server
->srv_mutex
);
997 rc
= allocate_mid(ses
, in_buf
, &midQ
);
999 mutex_unlock(&ses
->server
->srv_mutex
);
1003 rc
= cifs_sign_smb(in_buf
, ses
->server
, &midQ
->sequence_number
);
1005 cifs_delete_mid(midQ
);
1006 mutex_unlock(&ses
->server
->srv_mutex
);
1010 midQ
->mid_state
= MID_REQUEST_SUBMITTED
;
1011 cifs_in_send_inc(ses
->server
);
1012 rc
= smb_send(ses
->server
, in_buf
, len
);
1013 cifs_in_send_dec(ses
->server
);
1014 cifs_save_when_sent(midQ
);
1017 ses
->server
->sequence_number
-= 2;
1019 mutex_unlock(&ses
->server
->srv_mutex
);
1022 cifs_delete_mid(midQ
);
1026 /* Wait for a reply - allow signals to interrupt. */
1027 rc
= wait_event_interruptible(ses
->server
->response_q
,
1028 (!(midQ
->mid_state
== MID_REQUEST_SUBMITTED
)) ||
1029 ((ses
->server
->tcpStatus
!= CifsGood
) &&
1030 (ses
->server
->tcpStatus
!= CifsNew
)));
1032 /* Were we interrupted by a signal ? */
1033 if ((rc
== -ERESTARTSYS
) &&
1034 (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) &&
1035 ((ses
->server
->tcpStatus
== CifsGood
) ||
1036 (ses
->server
->tcpStatus
== CifsNew
))) {
1038 if (in_buf
->Command
== SMB_COM_TRANSACTION2
) {
1039 /* POSIX lock. We send a NT_CANCEL SMB to cause the
1040 blocking lock to return. */
1041 rc
= send_cancel(ses
->server
, &rqst
, midQ
);
1043 cifs_delete_mid(midQ
);
1047 /* Windows lock. We send a LOCKINGX_CANCEL_LOCK
1048 to cause the blocking lock to return. */
1050 rc
= send_lock_cancel(xid
, tcon
, in_buf
, out_buf
);
1052 /* If we get -ENOLCK back the lock may have
1053 already been removed. Don't exit in this case. */
1054 if (rc
&& rc
!= -ENOLCK
) {
1055 cifs_delete_mid(midQ
);
1060 rc
= wait_for_response(ses
->server
, midQ
);
1062 send_cancel(ses
->server
, &rqst
, midQ
);
1063 spin_lock(&GlobalMid_Lock
);
1064 if (midQ
->mid_state
== MID_REQUEST_SUBMITTED
) {
1065 /* no longer considered to be "in-flight" */
1066 midQ
->callback
= DeleteMidQEntry
;
1067 spin_unlock(&GlobalMid_Lock
);
1070 spin_unlock(&GlobalMid_Lock
);
1073 /* We got the response - restart system call. */
1077 rc
= cifs_sync_mid_result(midQ
, ses
->server
);
1081 /* rcvd frame is ok */
1082 if (out_buf
== NULL
|| midQ
->mid_state
!= MID_RESPONSE_RECEIVED
) {
1084 cifs_dbg(VFS
, "Bad MID state?\n");
1088 *pbytes_returned
= get_rfc1002_length(midQ
->resp_buf
);
1089 memcpy(out_buf
, midQ
->resp_buf
, *pbytes_returned
+ 4);
1090 rc
= cifs_check_receive(midQ
, ses
->server
, 0);
1092 cifs_delete_mid(midQ
);
1093 if (rstart
&& rc
== -EACCES
)
1094 return -ERESTARTSYS
;