Detach sched.h from mm.h
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / smbfs / request.c
CommitLineData
1da177e4
LT
1/*
2 * request.c
3 *
4 * Copyright (C) 2001 by Urban Widmark
5 *
6 * Please add a note about your changes to smbfs in the ChangeLog file.
7 */
8
1525dccb 9#include <linux/kernel.h>
1da177e4
LT
10#include <linux/types.h>
11#include <linux/fs.h>
12#include <linux/slab.h>
13#include <linux/net.h>
e8edc6e0 14#include <linux/sched.h>
1da177e4
LT
15
16#include <linux/smb_fs.h>
17#include <linux/smbno.h>
18#include <linux/smb_mount.h>
19
20#include "smb_debug.h"
21#include "request.h"
22#include "proto.h"
23
24/* #define SMB_SLAB_DEBUG (SLAB_RED_ZONE | SLAB_POISON) */
25#define SMB_SLAB_DEBUG 0
26
1da177e4 27/* cache for request structures */
e18b890b 28static struct kmem_cache *req_cachep;
1da177e4
LT
29
30static int smb_request_send_req(struct smb_request *req);
31
32/*
33 /proc/slabinfo:
34 name, active, num, objsize, active_slabs, num_slaps, #pages
35*/
36
37
38int smb_init_request_cache(void)
39{
40 req_cachep = kmem_cache_create("smb_request",
41 sizeof(struct smb_request), 0,
42 SMB_SLAB_DEBUG | SLAB_HWCACHE_ALIGN,
43 NULL, NULL);
44 if (req_cachep == NULL)
45 return -ENOMEM;
46
47 return 0;
48}
49
50void smb_destroy_request_cache(void)
51{
1a1d92c1 52 kmem_cache_destroy(req_cachep);
1da177e4
LT
53}
54
55/*
56 * Allocate and initialise a request structure
57 */
58static struct smb_request *smb_do_alloc_request(struct smb_sb_info *server,
59 int bufsize)
60{
61 struct smb_request *req;
62 unsigned char *buf = NULL;
63
c3762229 64 req = kmem_cache_zalloc(req_cachep, GFP_KERNEL);
1da177e4
LT
65 VERBOSE("allocating request: %p\n", req);
66 if (!req)
67 goto out;
68
69 if (bufsize > 0) {
d063389e 70 buf = kmalloc(bufsize, GFP_NOFS);
1da177e4
LT
71 if (!buf) {
72 kmem_cache_free(req_cachep, req);
73 return NULL;
74 }
75 }
76
1da177e4
LT
77 req->rq_buffer = buf;
78 req->rq_bufsize = bufsize;
79 req->rq_server = server;
80 init_waitqueue_head(&req->rq_wait);
81 INIT_LIST_HEAD(&req->rq_queue);
82 atomic_set(&req->rq_count, 1);
83
84out:
85 return req;
86}
87
88struct smb_request *smb_alloc_request(struct smb_sb_info *server, int bufsize)
89{
90 struct smb_request *req = NULL;
91
92 for (;;) {
93 atomic_inc(&server->nr_requests);
94 if (atomic_read(&server->nr_requests) <= MAX_REQUEST_HARD) {
95 req = smb_do_alloc_request(server, bufsize);
96 if (req != NULL)
97 break;
98 }
99
100#if 0
101 /*
102 * Try to free up at least one request in order to stay
103 * below the hard limit
104 */
105 if (nfs_try_to_free_pages(server))
106 continue;
107
108 if (signalled() && (server->flags & NFS_MOUNT_INTR))
109 return ERR_PTR(-ERESTARTSYS);
110 current->policy = SCHED_YIELD;
111 schedule();
112#else
113 /* FIXME: we want something like nfs does above, but that
114 requires changes to all callers and can wait. */
115 break;
116#endif
117 }
118 return req;
119}
120
121static void smb_free_request(struct smb_request *req)
122{
123 atomic_dec(&req->rq_server->nr_requests);
124 if (req->rq_buffer && !(req->rq_flags & SMB_REQ_STATIC))
d063389e
PE
125 kfree(req->rq_buffer);
126 kfree(req->rq_trans2buffer);
1da177e4
LT
127 kmem_cache_free(req_cachep, req);
128}
129
130/*
131 * What prevents a rget to race with a rput? The count must never drop to zero
132 * while it is in use. Only rput if it is ok that it is free'd.
133 */
134static void smb_rget(struct smb_request *req)
135{
136 atomic_inc(&req->rq_count);
137}
138void smb_rput(struct smb_request *req)
139{
140 if (atomic_dec_and_test(&req->rq_count)) {
141 list_del_init(&req->rq_queue);
142 smb_free_request(req);
143 }
144}
145
146/* setup to receive the data part of the SMB */
147static int smb_setup_bcc(struct smb_request *req)
148{
149 int result = 0;
150 req->rq_rlen = smb_len(req->rq_header) + 4 - req->rq_bytes_recvd;
151
152 if (req->rq_rlen > req->rq_bufsize) {
153 PARANOIA("Packet too large %d > %d\n",
154 req->rq_rlen, req->rq_bufsize);
155 return -ENOBUFS;
156 }
157
158 req->rq_iov[0].iov_base = req->rq_buffer;
159 req->rq_iov[0].iov_len = req->rq_rlen;
160 req->rq_iovlen = 1;
161
162 return result;
163}
164
165/*
166 * Prepare a "normal" request structure.
167 */
168static int smb_setup_request(struct smb_request *req)
169{
170 int len = smb_len(req->rq_header) + 4;
171 req->rq_slen = len;
172
173 /* if we expect a data part in the reply we set the iov's to read it */
174 if (req->rq_resp_bcc)
175 req->rq_setup_read = smb_setup_bcc;
176
177 /* This tries to support re-using the same request */
178 req->rq_bytes_sent = 0;
179 req->rq_rcls = 0;
180 req->rq_err = 0;
181 req->rq_errno = 0;
182 req->rq_fragment = 0;
d063389e 183 kfree(req->rq_trans2buffer);
1174cf73 184 req->rq_trans2buffer = NULL;
1da177e4
LT
185
186 return 0;
187}
188
189/*
190 * Prepare a transaction2 request structure
191 */
192static int smb_setup_trans2request(struct smb_request *req)
193{
194 struct smb_sb_info *server = req->rq_server;
195 int mparam, mdata;
196 static unsigned char padding[4];
197
198 /* I know the following is very ugly, but I want to build the
199 smb packet as efficiently as possible. */
200
201 const int smb_parameters = 15;
202 const int header = SMB_HEADER_LEN + 2 * smb_parameters + 2;
1525dccb
MAC
203 const int oparam = ALIGN(header + 3, sizeof(u32));
204 const int odata = ALIGN(oparam + req->rq_lparm, sizeof(u32));
1da177e4
LT
205 const int bcc = (req->rq_data ? odata + req->rq_ldata :
206 oparam + req->rq_lparm) - header;
207
208 if ((bcc + oparam) > server->opt.max_xmit)
209 return -ENOMEM;
210 smb_setup_header(req, SMBtrans2, smb_parameters, bcc);
211
212 /*
213 * max parameters + max data + max setup == bufsize to make NT4 happy
214 * and not abort the transfer or split into multiple responses. It also
215 * makes smbfs happy as handling packets larger than the buffer size
216 * is extra work.
217 *
218 * OS/2 is probably going to hate me for this ...
219 */
220 mparam = SMB_TRANS2_MAX_PARAM;
221 mdata = req->rq_bufsize - mparam;
222
223 mdata = server->opt.max_xmit - mparam - 100;
224 if (mdata < 1024) {
225 mdata = 1024;
226 mparam = 20;
227 }
228
229#if 0
230 /* NT/win2k has ~4k max_xmit, so with this we request more than it wants
231 to return as one SMB. Useful for testing the fragmented trans2
232 handling. */
233 mdata = 8192;
234#endif
235
236 WSET(req->rq_header, smb_tpscnt, req->rq_lparm);
237 WSET(req->rq_header, smb_tdscnt, req->rq_ldata);
238 WSET(req->rq_header, smb_mprcnt, mparam);
239 WSET(req->rq_header, smb_mdrcnt, mdata);
240 WSET(req->rq_header, smb_msrcnt, 0); /* max setup always 0 ? */
241 WSET(req->rq_header, smb_flags, 0);
242 DSET(req->rq_header, smb_timeout, 0);
243 WSET(req->rq_header, smb_pscnt, req->rq_lparm);
244 WSET(req->rq_header, smb_psoff, oparam - 4);
245 WSET(req->rq_header, smb_dscnt, req->rq_ldata);
246 WSET(req->rq_header, smb_dsoff, req->rq_data ? odata - 4 : 0);
247 *(req->rq_header + smb_suwcnt) = 0x01; /* setup count */
248 *(req->rq_header + smb_suwcnt + 1) = 0x00; /* reserved */
249 WSET(req->rq_header, smb_setup0, req->rq_trans2_command);
250
251 req->rq_iovlen = 2;
252 req->rq_iov[0].iov_base = (void *) req->rq_header;
253 req->rq_iov[0].iov_len = oparam;
254 req->rq_iov[1].iov_base = (req->rq_parm==NULL) ? padding : req->rq_parm;
255 req->rq_iov[1].iov_len = req->rq_lparm;
256 req->rq_slen = oparam + req->rq_lparm;
257
258 if (req->rq_data) {
259 req->rq_iovlen += 2;
260 req->rq_iov[2].iov_base = padding;
261 req->rq_iov[2].iov_len = odata - oparam - req->rq_lparm;
262 req->rq_iov[3].iov_base = req->rq_data;
263 req->rq_iov[3].iov_len = req->rq_ldata;
264 req->rq_slen = odata + req->rq_ldata;
265 }
266
267 /* always a data part for trans2 replies */
268 req->rq_setup_read = smb_setup_bcc;
269
270 return 0;
271}
272
273/*
274 * Add a request and tell smbiod to process it
275 */
276int smb_add_request(struct smb_request *req)
277{
278 long timeleft;
279 struct smb_sb_info *server = req->rq_server;
280 int result = 0;
281
282 smb_setup_request(req);
283 if (req->rq_trans2_command) {
284 if (req->rq_buffer == NULL) {
285 PARANOIA("trans2 attempted without response buffer!\n");
286 return -EIO;
287 }
288 result = smb_setup_trans2request(req);
289 }
290 if (result < 0)
291 return result;
292
293#ifdef SMB_DEBUG_PACKET_SIZE
294 add_xmit_stats(req);
295#endif
296
297 /* add 'req' to the queue of requests */
298 if (smb_lock_server_interruptible(server))
299 return -EINTR;
300
301 /*
302 * Try to send the request as the process. If that fails we queue the
303 * request and let smbiod send it later.
304 */
305
306 /* FIXME: each server has a number on the maximum number of parallel
307 requests. 10, 50 or so. We should not allow more requests to be
308 active. */
309 if (server->mid > 0xf000)
310 server->mid = 0;
311 req->rq_mid = server->mid++;
312 WSET(req->rq_header, smb_mid, req->rq_mid);
313
314 result = 0;
315 if (server->state == CONN_VALID) {
316 if (list_empty(&server->xmitq))
317 result = smb_request_send_req(req);
318 if (result < 0) {
319 /* Connection lost? */
320 server->conn_error = result;
321 server->state = CONN_INVALID;
322 }
323 }
324 if (result != 1)
325 list_add_tail(&req->rq_queue, &server->xmitq);
326 smb_rget(req);
327
328 if (server->state != CONN_VALID)
329 smbiod_retry(server);
330
331 smb_unlock_server(server);
332
333 smbiod_wake_up();
334
335 timeleft = wait_event_interruptible_timeout(req->rq_wait,
336 req->rq_flags & SMB_REQ_RECEIVED, 30*HZ);
337 if (!timeleft || signal_pending(current)) {
338 /*
339 * On timeout or on interrupt we want to try and remove the
340 * request from the recvq/xmitq.
48564e62
JN
341 * First check if the request is still part of a queue. (May
342 * have been removed by some error condition)
1da177e4
LT
343 */
344 smb_lock_server(server);
48564e62 345 if (!list_empty(&req->rq_queue)) {
1da177e4
LT
346 list_del_init(&req->rq_queue);
347 smb_rput(req);
348 }
349 smb_unlock_server(server);
350 }
351
352 if (!timeleft) {
353 PARANOIA("request [%p, mid=%d] timed out!\n",
354 req, req->rq_mid);
355 VERBOSE("smb_com: %02x\n", *(req->rq_header + smb_com));
356 VERBOSE("smb_rcls: %02x\n", *(req->rq_header + smb_rcls));
357 VERBOSE("smb_flg: %02x\n", *(req->rq_header + smb_flg));
358 VERBOSE("smb_tid: %04x\n", WVAL(req->rq_header, smb_tid));
359 VERBOSE("smb_pid: %04x\n", WVAL(req->rq_header, smb_pid));
360 VERBOSE("smb_uid: %04x\n", WVAL(req->rq_header, smb_uid));
361 VERBOSE("smb_mid: %04x\n", WVAL(req->rq_header, smb_mid));
362 VERBOSE("smb_wct: %02x\n", *(req->rq_header + smb_wct));
363
364 req->rq_rcls = ERRSRV;
365 req->rq_err = ERRtimeout;
366
367 /* Just in case it was "stuck" */
368 smbiod_wake_up();
369 }
370 VERBOSE("woke up, rcls=%d\n", req->rq_rcls);
371
372 if (req->rq_rcls != 0)
373 req->rq_errno = smb_errno(req);
374 if (signal_pending(current))
375 req->rq_errno = -ERESTARTSYS;
376 return req->rq_errno;
377}
378
379/*
380 * Send a request and place it on the recvq if successfully sent.
381 * Must be called with the server lock held.
382 */
383static int smb_request_send_req(struct smb_request *req)
384{
385 struct smb_sb_info *server = req->rq_server;
386 int result;
387
388 if (req->rq_bytes_sent == 0) {
389 WSET(req->rq_header, smb_tid, server->opt.tid);
390 WSET(req->rq_header, smb_pid, 1);
391 WSET(req->rq_header, smb_uid, server->opt.server_uid);
392 }
393
394 result = smb_send_request(req);
395 if (result < 0 && result != -EAGAIN)
396 goto out;
397
398 result = 0;
399 if (!(req->rq_flags & SMB_REQ_TRANSMITTED))
400 goto out;
401
f116629d 402 list_move_tail(&req->rq_queue, &server->recvq);
1da177e4
LT
403 result = 1;
404out:
405 return result;
406}
407
408/*
409 * Sends one request for this server. (smbiod)
410 * Must be called with the server lock held.
411 * Returns: <0 on error
412 * 0 if no request could be completely sent
413 * 1 if all data for one request was sent
414 */
415int smb_request_send_server(struct smb_sb_info *server)
416{
417 struct list_head *head;
418 struct smb_request *req;
419 int result;
420
421 if (server->state != CONN_VALID)
422 return 0;
423
424 /* dequeue first request, if any */
425 req = NULL;
426 head = server->xmitq.next;
427 if (head != &server->xmitq) {
428 req = list_entry(head, struct smb_request, rq_queue);
429 }
430 if (!req)
431 return 0;
432
433 result = smb_request_send_req(req);
434 if (result < 0) {
435 server->conn_error = result;
f116629d 436 list_move(&req->rq_queue, &server->xmitq);
1da177e4
LT
437 result = -EIO;
438 goto out;
439 }
440
441out:
442 return result;
443}
444
445/*
446 * Try to find a request matching this "mid". Typically the first entry will
447 * be the matching one.
448 */
449static struct smb_request *find_request(struct smb_sb_info *server, int mid)
450{
451 struct list_head *tmp;
452 struct smb_request *req = NULL;
453
454 list_for_each(tmp, &server->recvq) {
455 req = list_entry(tmp, struct smb_request, rq_queue);
456 if (req->rq_mid == mid) {
457 break;
458 }
459 req = NULL;
460 }
461
462 if (!req) {
463 VERBOSE("received reply with mid %d but no request!\n",
464 WVAL(server->header, smb_mid));
465 server->rstate = SMB_RECV_DROP;
466 }
467
468 return req;
469}
470
471/*
472 * Called when we have read the smb header and believe this is a response.
473 */
474static int smb_init_request(struct smb_sb_info *server, struct smb_request *req)
475{
476 int hdrlen, wct;
477
478 memcpy(req->rq_header, server->header, SMB_HEADER_LEN);
479
480 wct = *(req->rq_header + smb_wct);
481 if (wct > 20) {
482 PARANOIA("wct too large, %d > 20\n", wct);
483 server->rstate = SMB_RECV_DROP;
484 return 0;
485 }
486
487 req->rq_resp_wct = wct;
488 hdrlen = SMB_HEADER_LEN + wct*2 + 2;
489 VERBOSE("header length: %d smb_wct: %2d\n", hdrlen, wct);
490
491 req->rq_bytes_recvd = SMB_HEADER_LEN;
492 req->rq_rlen = hdrlen;
493 req->rq_iov[0].iov_base = req->rq_header;
494 req->rq_iov[0].iov_len = hdrlen;
495 req->rq_iovlen = 1;
496 server->rstate = SMB_RECV_PARAM;
497
498#ifdef SMB_DEBUG_PACKET_SIZE
499 add_recv_stats(smb_len(server->header));
500#endif
501 return 0;
502}
503
504/*
505 * Reads the SMB parameters
506 */
507static int smb_recv_param(struct smb_sb_info *server, struct smb_request *req)
508{
509 int result;
510
511 result = smb_receive(server, req);
512 if (result < 0)
513 return result;
514 if (req->rq_bytes_recvd < req->rq_rlen)
515 return 0;
516
517 VERBOSE("result: %d smb_bcc: %04x\n", result,
518 WVAL(req->rq_header, SMB_HEADER_LEN +
519 (*(req->rq_header + smb_wct) * 2)));
520
521 result = 0;
522 req->rq_iov[0].iov_base = NULL;
523 req->rq_rlen = 0;
524 if (req->rq_callback)
525 req->rq_callback(req);
526 else if (req->rq_setup_read)
527 result = req->rq_setup_read(req);
528 if (result < 0) {
529 server->rstate = SMB_RECV_DROP;
530 return result;
531 }
532
533 server->rstate = req->rq_rlen > 0 ? SMB_RECV_DATA : SMB_RECV_END;
534
535 req->rq_bytes_recvd = 0; // recvd out of the iov
536
537 VERBOSE("rlen: %d\n", req->rq_rlen);
538 if (req->rq_rlen < 0) {
539 PARANOIA("Parameters read beyond end of packet!\n");
540 server->rstate = SMB_RECV_END;
541 return -EIO;
542 }
543 return 0;
544}
545
546/*
547 * Reads the SMB data
548 */
549static int smb_recv_data(struct smb_sb_info *server, struct smb_request *req)
550{
551 int result;
552
553 result = smb_receive(server, req);
554 if (result < 0)
555 goto out;
556 if (req->rq_bytes_recvd < req->rq_rlen)
557 goto out;
558 server->rstate = SMB_RECV_END;
559out:
560 VERBOSE("result: %d\n", result);
561 return result;
562}
563
564/*
565 * Receive a transaction2 response
566 * Return: 0 if the response has been fully read
567 * 1 if there are further "fragments" to read
568 * <0 if there is an error
569 */
570static int smb_recv_trans2(struct smb_sb_info *server, struct smb_request *req)
571{
572 unsigned char *inbuf;
573 unsigned int parm_disp, parm_offset, parm_count, parm_tot;
574 unsigned int data_disp, data_offset, data_count, data_tot;
575 int hdrlen = SMB_HEADER_LEN + req->rq_resp_wct*2 - 2;
576
577 VERBOSE("handling trans2\n");
578
579 inbuf = req->rq_header;
580 data_tot = WVAL(inbuf, smb_tdrcnt);
581 parm_tot = WVAL(inbuf, smb_tprcnt);
582 parm_disp = WVAL(inbuf, smb_prdisp);
583 parm_offset = WVAL(inbuf, smb_proff);
584 parm_count = WVAL(inbuf, smb_prcnt);
585 data_disp = WVAL(inbuf, smb_drdisp);
586 data_offset = WVAL(inbuf, smb_droff);
587 data_count = WVAL(inbuf, smb_drcnt);
588
589 /* Modify offset for the split header/buffer we use */
590 if (data_count || data_offset) {
591 if (unlikely(data_offset < hdrlen))
592 goto out_bad_data;
593 else
594 data_offset -= hdrlen;
595 }
596 if (parm_count || parm_offset) {
597 if (unlikely(parm_offset < hdrlen))
598 goto out_bad_parm;
599 else
600 parm_offset -= hdrlen;
601 }
602
603 if (parm_count == parm_tot && data_count == data_tot) {
604 /*
605 * This packet has all the trans2 data.
606 *
607 * We setup the request so that this will be the common
608 * case. It may be a server error to not return a
609 * response that fits.
610 */
611 VERBOSE("single trans2 response "
612 "dcnt=%u, pcnt=%u, doff=%u, poff=%u\n",
613 data_count, parm_count,
614 data_offset, parm_offset);
615 req->rq_ldata = data_count;
616 req->rq_lparm = parm_count;
617 req->rq_data = req->rq_buffer + data_offset;
618 req->rq_parm = req->rq_buffer + parm_offset;
619 if (unlikely(parm_offset + parm_count > req->rq_rlen))
620 goto out_bad_parm;
621 if (unlikely(data_offset + data_count > req->rq_rlen))
622 goto out_bad_data;
623 return 0;
624 }
625
626 VERBOSE("multi trans2 response "
627 "frag=%d, dcnt=%u, pcnt=%u, doff=%u, poff=%u\n",
628 req->rq_fragment,
629 data_count, parm_count,
630 data_offset, parm_offset);
631
632 if (!req->rq_fragment) {
633 int buf_len;
634
635 /* We got the first trans2 fragment */
636 req->rq_fragment = 1;
637 req->rq_total_data = data_tot;
638 req->rq_total_parm = parm_tot;
639 req->rq_ldata = 0;
640 req->rq_lparm = 0;
641
642 buf_len = data_tot + parm_tot;
643 if (buf_len > SMB_MAX_PACKET_SIZE)
644 goto out_too_long;
645
646 req->rq_trans2bufsize = buf_len;
d063389e 647 req->rq_trans2buffer = kzalloc(buf_len, GFP_NOFS);
1da177e4
LT
648 if (!req->rq_trans2buffer)
649 goto out_no_mem;
1da177e4
LT
650
651 req->rq_parm = req->rq_trans2buffer;
652 req->rq_data = req->rq_trans2buffer + parm_tot;
653 } else if (unlikely(req->rq_total_data < data_tot ||
654 req->rq_total_parm < parm_tot))
655 goto out_data_grew;
656
657 if (unlikely(parm_disp + parm_count > req->rq_total_parm ||
658 parm_offset + parm_count > req->rq_rlen))
659 goto out_bad_parm;
660 if (unlikely(data_disp + data_count > req->rq_total_data ||
661 data_offset + data_count > req->rq_rlen))
662 goto out_bad_data;
663
664 inbuf = req->rq_buffer;
665 memcpy(req->rq_parm + parm_disp, inbuf + parm_offset, parm_count);
666 memcpy(req->rq_data + data_disp, inbuf + data_offset, data_count);
667
668 req->rq_ldata += data_count;
669 req->rq_lparm += parm_count;
670
671 /*
672 * Check whether we've received all of the data. Note that
673 * we use the packet totals -- total lengths might shrink!
674 */
675 if (req->rq_ldata >= data_tot && req->rq_lparm >= parm_tot) {
676 req->rq_ldata = data_tot;
677 req->rq_lparm = parm_tot;
678 return 0;
679 }
680 return 1;
681
682out_too_long:
683 printk(KERN_ERR "smb_trans2: data/param too long, data=%u, parm=%u\n",
684 data_tot, parm_tot);
685 goto out_EIO;
686out_no_mem:
687 printk(KERN_ERR "smb_trans2: couldn't allocate data area of %d bytes\n",
688 req->rq_trans2bufsize);
689 req->rq_errno = -ENOMEM;
690 goto out;
691out_data_grew:
692 printk(KERN_ERR "smb_trans2: data/params grew!\n");
693 goto out_EIO;
694out_bad_parm:
695 printk(KERN_ERR "smb_trans2: invalid parms, disp=%u, cnt=%u, tot=%u, ofs=%u\n",
696 parm_disp, parm_count, parm_tot, parm_offset);
697 goto out_EIO;
698out_bad_data:
699 printk(KERN_ERR "smb_trans2: invalid data, disp=%u, cnt=%u, tot=%u, ofs=%u\n",
700 data_disp, data_count, data_tot, data_offset);
701out_EIO:
702 req->rq_errno = -EIO;
703out:
704 return req->rq_errno;
705}
706
707/*
708 * State machine for receiving responses. We handle the fact that we can't
709 * read the full response in one try by having states telling us how much we
710 * have read.
711 *
712 * Must be called with the server lock held (only called from smbiod).
713 *
714 * Return: <0 on error
715 */
716int smb_request_recv(struct smb_sb_info *server)
717{
718 struct smb_request *req = NULL;
719 int result = 0;
720
721 if (smb_recv_available(server) <= 0)
722 return 0;
723
724 VERBOSE("state: %d\n", server->rstate);
725 switch (server->rstate) {
726 case SMB_RECV_DROP:
727 result = smb_receive_drop(server);
728 if (result < 0)
729 break;
730 if (server->rstate == SMB_RECV_DROP)
731 break;
732 server->rstate = SMB_RECV_START;
733 /* fallthrough */
734 case SMB_RECV_START:
735 server->smb_read = 0;
736 server->rstate = SMB_RECV_HEADER;
737 /* fallthrough */
738 case SMB_RECV_HEADER:
739 result = smb_receive_header(server);
740 if (result < 0)
741 break;
742 if (server->rstate == SMB_RECV_HEADER)
743 break;
744 if (! (*(server->header + smb_flg) & SMB_FLAGS_REPLY) ) {
745 server->rstate = SMB_RECV_REQUEST;
746 break;
747 }
748 if (server->rstate != SMB_RECV_HCOMPLETE)
749 break;
750 /* fallthrough */
751 case SMB_RECV_HCOMPLETE:
752 req = find_request(server, WVAL(server->header, smb_mid));
753 if (!req)
754 break;
755 smb_init_request(server, req);
756 req->rq_rcls = *(req->rq_header + smb_rcls);
757 req->rq_err = WVAL(req->rq_header, smb_err);
758 if (server->rstate != SMB_RECV_PARAM)
759 break;
760 /* fallthrough */
761 case SMB_RECV_PARAM:
762 if (!req)
763 req = find_request(server,WVAL(server->header,smb_mid));
764 if (!req)
765 break;
766 result = smb_recv_param(server, req);
767 if (result < 0)
768 break;
769 if (server->rstate != SMB_RECV_DATA)
770 break;
771 /* fallthrough */
772 case SMB_RECV_DATA:
773 if (!req)
774 req = find_request(server,WVAL(server->header,smb_mid));
775 if (!req)
776 break;
777 result = smb_recv_data(server, req);
778 if (result < 0)
779 break;
780 break;
781
782 /* We should never be called with any of these states */
783 case SMB_RECV_END:
784 case SMB_RECV_REQUEST:
ccb6e363 785 BUG();
1da177e4
LT
786 }
787
788 if (result < 0) {
789 /* We saw an error */
790 return result;
791 }
792
793 if (server->rstate != SMB_RECV_END)
794 return 0;
795
796 result = 0;
797 if (req->rq_trans2_command && req->rq_rcls == SUCCESS)
798 result = smb_recv_trans2(server, req);
799
800 /*
801 * Response completely read. Drop any extra bytes sent by the server.
802 * (Yes, servers sometimes add extra bytes to responses)
803 */
804 VERBOSE("smb_len: %d smb_read: %d\n",
805 server->smb_len, server->smb_read);
806 if (server->smb_read < server->smb_len)
807 smb_receive_drop(server);
808
809 server->rstate = SMB_RECV_START;
810
811 if (!result) {
812 list_del_init(&req->rq_queue);
813 req->rq_flags |= SMB_REQ_RECEIVED;
814 smb_rput(req);
815 wake_up_interruptible(&req->rq_wait);
816 }
817 return 0;
818}