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29#include <linux/types.h>
30#include <linux/list.h>
31#include <linux/inet.h>
32#include <linux/file.h>
33#include <linux/blkdev.h>
34#include <linux/crypto.h>
35#include <linux/delay.h>
36#include <linux/kfifo.h>
37#include <linux/scatterlist.h>
38#include <net/tcp.h>
39#include <scsi/scsi_cmnd.h>
40#include <scsi/scsi_device.h>
41#include <scsi/scsi_host.h>
42#include <scsi/scsi.h>
43#include <scsi/scsi_transport_iscsi.h>
44
45#include "iscsi_tcp.h"
46
47MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
48 "Dmitry Yusupov <dmitry_yus@yahoo.com>, "
49 "Alex Aizman <itn780@yahoo.com>");
50MODULE_DESCRIPTION("iSCSI/TCP data-path");
51MODULE_LICENSE("GPL");
52
53static int iscsi_dbg_libtcp;
54module_param_named(debug_libiscsi_tcp, iscsi_dbg_libtcp, int,
55 S_IRUGO | S_IWUSR);
56MODULE_PARM_DESC(debug_libiscsi_tcp, "Turn on debugging for libiscsi_tcp "
57 "module. Set to 1 to turn on, and zero to turn off. Default "
58 "is off.");
59
60#define ISCSI_DBG_TCP(_conn, dbg_fmt, arg...) \
61 do { \
62 if (iscsi_dbg_libtcp) \
63 iscsi_conn_printk(KERN_INFO, _conn, \
64 "%s " dbg_fmt, \
65 __func__, ##arg); \
66 } while (0);
67
68static int iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
69 struct iscsi_segment *segment);
70
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93
94static inline void
95iscsi_tcp_segment_init_sg(struct iscsi_segment *segment,
96 struct scatterlist *sg, unsigned int offset)
97{
98 segment->sg = sg;
99 segment->sg_offset = offset;
100 segment->size = min(sg->length - offset,
101 segment->total_size - segment->total_copied);
102 segment->data = NULL;
103}
104
105
106
107
108
109
110
111
112
113
114static void iscsi_tcp_segment_map(struct iscsi_segment *segment, int recv)
115{
116 struct scatterlist *sg;
117
118 if (segment->data != NULL || !segment->sg)
119 return;
120
121 sg = segment->sg;
122 BUG_ON(segment->sg_mapped);
123 BUG_ON(sg->length == 0);
124
125
126
127
128
129
130
131 if (page_count(sg_page(sg)) >= 1 && !recv)
132 return;
133
134 segment->sg_mapped = kmap_atomic(sg_page(sg), KM_SOFTIRQ0);
135 segment->data = segment->sg_mapped + sg->offset + segment->sg_offset;
136}
137
138void iscsi_tcp_segment_unmap(struct iscsi_segment *segment)
139{
140 if (segment->sg_mapped) {
141 kunmap_atomic(segment->sg_mapped, KM_SOFTIRQ0);
142 segment->sg_mapped = NULL;
143 segment->data = NULL;
144 }
145}
146EXPORT_SYMBOL_GPL(iscsi_tcp_segment_unmap);
147
148
149
150
151static inline void
152iscsi_tcp_segment_splice_digest(struct iscsi_segment *segment, void *digest)
153{
154 segment->data = digest;
155 segment->digest_len = ISCSI_DIGEST_SIZE;
156 segment->total_size += ISCSI_DIGEST_SIZE;
157 segment->size = ISCSI_DIGEST_SIZE;
158 segment->copied = 0;
159 segment->sg = NULL;
160 segment->hash = NULL;
161}
162
163
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166
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171
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173
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175
176
177
178
179int iscsi_tcp_segment_done(struct iscsi_tcp_conn *tcp_conn,
180 struct iscsi_segment *segment, int recv,
181 unsigned copied)
182{
183 struct scatterlist sg;
184 unsigned int pad;
185
186 ISCSI_DBG_TCP(tcp_conn->iscsi_conn, "copied %u %u size %u %s\n",
187 segment->copied, copied, segment->size,
188 recv ? "recv" : "xmit");
189 if (segment->hash && copied) {
190
191
192
193
194 iscsi_tcp_segment_unmap(segment);
195
196 if (!segment->data) {
197 sg_init_table(&sg, 1);
198 sg_set_page(&sg, sg_page(segment->sg), copied,
199 segment->copied + segment->sg_offset +
200 segment->sg->offset);
201 } else
202 sg_init_one(&sg, segment->data + segment->copied,
203 copied);
204 crypto_hash_update(segment->hash, &sg, copied);
205 }
206
207 segment->copied += copied;
208 if (segment->copied < segment->size) {
209 iscsi_tcp_segment_map(segment, recv);
210 return 0;
211 }
212
213 segment->total_copied += segment->copied;
214 segment->copied = 0;
215 segment->size = 0;
216
217
218 iscsi_tcp_segment_unmap(segment);
219
220
221 ISCSI_DBG_TCP(tcp_conn->iscsi_conn, "total copied %u total size %u\n",
222 segment->total_copied, segment->total_size);
223 if (segment->total_copied < segment->total_size) {
224
225 iscsi_tcp_segment_init_sg(segment, sg_next(segment->sg),
226 0);
227 iscsi_tcp_segment_map(segment, recv);
228 BUG_ON(segment->size == 0);
229 return 0;
230 }
231
232
233 if (!(tcp_conn->iscsi_conn->session->tt->caps & CAP_PADDING_OFFLOAD)) {
234 pad = iscsi_padding(segment->total_copied);
235 if (pad != 0) {
236 ISCSI_DBG_TCP(tcp_conn->iscsi_conn,
237 "consume %d pad bytes\n", pad);
238 segment->total_size += pad;
239 segment->size = pad;
240 segment->data = segment->padbuf;
241 return 0;
242 }
243 }
244
245
246
247
248
249 if (segment->hash) {
250 crypto_hash_final(segment->hash, segment->digest);
251 iscsi_tcp_segment_splice_digest(segment,
252 recv ? segment->recv_digest : segment->digest);
253 return 0;
254 }
255
256 return 1;
257}
258EXPORT_SYMBOL_GPL(iscsi_tcp_segment_done);
259
260
261
262
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274
275
276
277static int
278iscsi_tcp_segment_recv(struct iscsi_tcp_conn *tcp_conn,
279 struct iscsi_segment *segment, const void *ptr,
280 unsigned int len)
281{
282 unsigned int copy = 0, copied = 0;
283
284 while (!iscsi_tcp_segment_done(tcp_conn, segment, 1, copy)) {
285 if (copied == len) {
286 ISCSI_DBG_TCP(tcp_conn->iscsi_conn,
287 "copied %d bytes\n", len);
288 break;
289 }
290
291 copy = min(len - copied, segment->size - segment->copied);
292 ISCSI_DBG_TCP(tcp_conn->iscsi_conn, "copying %d\n", copy);
293 memcpy(segment->data + segment->copied, ptr + copied, copy);
294 copied += copy;
295 }
296 return copied;
297}
298
299inline void
300iscsi_tcp_dgst_header(struct hash_desc *hash, const void *hdr, size_t hdrlen,
301 unsigned char digest[ISCSI_DIGEST_SIZE])
302{
303 struct scatterlist sg;
304
305 sg_init_one(&sg, hdr, hdrlen);
306 crypto_hash_digest(hash, &sg, hdrlen, digest);
307}
308EXPORT_SYMBOL_GPL(iscsi_tcp_dgst_header);
309
310static inline int
311iscsi_tcp_dgst_verify(struct iscsi_tcp_conn *tcp_conn,
312 struct iscsi_segment *segment)
313{
314 if (!segment->digest_len)
315 return 1;
316
317 if (memcmp(segment->recv_digest, segment->digest,
318 segment->digest_len)) {
319 ISCSI_DBG_TCP(tcp_conn->iscsi_conn, "digest mismatch\n");
320 return 0;
321 }
322
323 return 1;
324}
325
326
327
328
329static inline void
330__iscsi_segment_init(struct iscsi_segment *segment, size_t size,
331 iscsi_segment_done_fn_t *done, struct hash_desc *hash)
332{
333 memset(segment, 0, sizeof(*segment));
334 segment->total_size = size;
335 segment->done = done;
336
337 if (hash) {
338 segment->hash = hash;
339 crypto_hash_init(hash);
340 }
341}
342
343inline void
344iscsi_segment_init_linear(struct iscsi_segment *segment, void *data,
345 size_t size, iscsi_segment_done_fn_t *done,
346 struct hash_desc *hash)
347{
348 __iscsi_segment_init(segment, size, done, hash);
349 segment->data = data;
350 segment->size = size;
351}
352EXPORT_SYMBOL_GPL(iscsi_segment_init_linear);
353
354inline int
355iscsi_segment_seek_sg(struct iscsi_segment *segment,
356 struct scatterlist *sg_list, unsigned int sg_count,
357 unsigned int offset, size_t size,
358 iscsi_segment_done_fn_t *done, struct hash_desc *hash)
359{
360 struct scatterlist *sg;
361 unsigned int i;
362
363 __iscsi_segment_init(segment, size, done, hash);
364 for_each_sg(sg_list, sg, sg_count, i) {
365 if (offset < sg->length) {
366 iscsi_tcp_segment_init_sg(segment, sg, offset);
367 return 0;
368 }
369 offset -= sg->length;
370 }
371
372 return ISCSI_ERR_DATA_OFFSET;
373}
374EXPORT_SYMBOL_GPL(iscsi_segment_seek_sg);
375
376
377
378
379
380
381
382
383
384void iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn)
385{
386 ISCSI_DBG_TCP(tcp_conn->iscsi_conn,
387 "(%s)\n", tcp_conn->iscsi_conn->hdrdgst_en ?
388 "digest enabled" : "digest disabled");
389 iscsi_segment_init_linear(&tcp_conn->in.segment,
390 tcp_conn->in.hdr_buf, sizeof(struct iscsi_hdr),
391 iscsi_tcp_hdr_recv_done, NULL);
392}
393EXPORT_SYMBOL_GPL(iscsi_tcp_hdr_recv_prep);
394
395
396
397
398static int
399iscsi_tcp_data_recv_done(struct iscsi_tcp_conn *tcp_conn,
400 struct iscsi_segment *segment)
401{
402 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
403 int rc = 0;
404
405 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
406 return ISCSI_ERR_DATA_DGST;
407
408 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr,
409 conn->data, tcp_conn->in.datalen);
410 if (rc)
411 return rc;
412
413 iscsi_tcp_hdr_recv_prep(tcp_conn);
414 return 0;
415}
416
417static void
418iscsi_tcp_data_recv_prep(struct iscsi_tcp_conn *tcp_conn)
419{
420 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
421 struct hash_desc *rx_hash = NULL;
422
423 if (conn->datadgst_en &
424 !(conn->session->tt->caps & CAP_DIGEST_OFFLOAD))
425 rx_hash = tcp_conn->rx_hash;
426
427 iscsi_segment_init_linear(&tcp_conn->in.segment,
428 conn->data, tcp_conn->in.datalen,
429 iscsi_tcp_data_recv_done, rx_hash);
430}
431
432
433
434
435
436
437
438void iscsi_tcp_cleanup_task(struct iscsi_task *task)
439{
440 struct iscsi_tcp_task *tcp_task = task->dd_data;
441 struct iscsi_r2t_info *r2t;
442
443
444 if (!task->sc)
445 return;
446
447
448 while (__kfifo_get(tcp_task->r2tqueue, (void*)&r2t, sizeof(void*))) {
449 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
450 sizeof(void*));
451 ISCSI_DBG_TCP(task->conn, "pending r2t dropped\n");
452 }
453
454 r2t = tcp_task->r2t;
455 if (r2t != NULL) {
456 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
457 sizeof(void*));
458 tcp_task->r2t = NULL;
459 }
460}
461EXPORT_SYMBOL_GPL(iscsi_tcp_cleanup_task);
462
463
464
465
466
467
468static int iscsi_tcp_data_in(struct iscsi_conn *conn, struct iscsi_task *task)
469{
470 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
471 struct iscsi_tcp_task *tcp_task = task->dd_data;
472 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
473 int datasn = be32_to_cpu(rhdr->datasn);
474 unsigned total_in_length = scsi_in(task->sc)->length;
475
476
477
478
479
480 if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
481 iscsi_update_cmdsn(conn->session, (struct iscsi_nopin*)rhdr);
482
483 if (tcp_conn->in.datalen == 0)
484 return 0;
485
486 if (tcp_task->exp_datasn != datasn) {
487 ISCSI_DBG_TCP(conn, "task->exp_datasn(%d) != rhdr->datasn(%d)"
488 "\n", tcp_task->exp_datasn, datasn);
489 return ISCSI_ERR_DATASN;
490 }
491
492 tcp_task->exp_datasn++;
493
494 tcp_task->data_offset = be32_to_cpu(rhdr->offset);
495 if (tcp_task->data_offset + tcp_conn->in.datalen > total_in_length) {
496 ISCSI_DBG_TCP(conn, "data_offset(%d) + data_len(%d) > "
497 "total_length_in(%d)\n", tcp_task->data_offset,
498 tcp_conn->in.datalen, total_in_length);
499 return ISCSI_ERR_DATA_OFFSET;
500 }
501
502 conn->datain_pdus_cnt++;
503 return 0;
504}
505
506
507
508
509
510
511static int iscsi_tcp_r2t_rsp(struct iscsi_conn *conn, struct iscsi_task *task)
512{
513 struct iscsi_session *session = conn->session;
514 struct iscsi_tcp_task *tcp_task = task->dd_data;
515 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
516 struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
517 struct iscsi_r2t_info *r2t;
518 int r2tsn = be32_to_cpu(rhdr->r2tsn);
519 int rc;
520
521 if (tcp_conn->in.datalen) {
522 iscsi_conn_printk(KERN_ERR, conn,
523 "invalid R2t with datalen %d\n",
524 tcp_conn->in.datalen);
525 return ISCSI_ERR_DATALEN;
526 }
527
528 if (tcp_task->exp_datasn != r2tsn){
529 ISCSI_DBG_TCP(conn, "task->exp_datasn(%d) != rhdr->r2tsn(%d)\n",
530 tcp_task->exp_datasn, r2tsn);
531 return ISCSI_ERR_R2TSN;
532 }
533
534
535 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
536
537 if (!task->sc || session->state != ISCSI_STATE_LOGGED_IN) {
538 iscsi_conn_printk(KERN_INFO, conn,
539 "dropping R2T itt %d in recovery.\n",
540 task->itt);
541 return 0;
542 }
543
544 rc = __kfifo_get(tcp_task->r2tpool.queue, (void*)&r2t, sizeof(void*));
545 if (!rc) {
546 iscsi_conn_printk(KERN_ERR, conn, "Could not allocate R2T. "
547 "Target has sent more R2Ts than it "
548 "negotiated for or driver has has leaked.\n");
549 return ISCSI_ERR_PROTO;
550 }
551
552 r2t->exp_statsn = rhdr->statsn;
553 r2t->data_length = be32_to_cpu(rhdr->data_length);
554 if (r2t->data_length == 0) {
555 iscsi_conn_printk(KERN_ERR, conn,
556 "invalid R2T with zero data len\n");
557 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
558 sizeof(void*));
559 return ISCSI_ERR_DATALEN;
560 }
561
562 if (r2t->data_length > session->max_burst)
563 ISCSI_DBG_TCP(conn, "invalid R2T with data len %u and max "
564 "burst %u. Attempting to execute request.\n",
565 r2t->data_length, session->max_burst);
566
567 r2t->data_offset = be32_to_cpu(rhdr->data_offset);
568 if (r2t->data_offset + r2t->data_length > scsi_out(task->sc)->length) {
569 iscsi_conn_printk(KERN_ERR, conn,
570 "invalid R2T with data len %u at offset %u "
571 "and total length %d\n", r2t->data_length,
572 r2t->data_offset, scsi_out(task->sc)->length);
573 __kfifo_put(tcp_task->r2tpool.queue, (void*)&r2t,
574 sizeof(void*));
575 return ISCSI_ERR_DATALEN;
576 }
577
578 r2t->ttt = rhdr->ttt;
579 r2t->datasn = 0;
580 r2t->sent = 0;
581
582 tcp_task->exp_datasn = r2tsn + 1;
583 __kfifo_put(tcp_task->r2tqueue, (void*)&r2t, sizeof(void*));
584 conn->r2t_pdus_cnt++;
585
586 iscsi_requeue_task(task);
587 return 0;
588}
589
590
591
592
593static int
594iscsi_tcp_process_data_in(struct iscsi_tcp_conn *tcp_conn,
595 struct iscsi_segment *segment)
596{
597 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
598 struct iscsi_hdr *hdr = tcp_conn->in.hdr;
599 int rc;
600
601 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
602 return ISCSI_ERR_DATA_DGST;
603
604
605 if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
606 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
607 if (rc)
608 return rc;
609 }
610
611 iscsi_tcp_hdr_recv_prep(tcp_conn);
612 return 0;
613}
614
615
616
617
618
619
620
621
622
623
624
625static int
626iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
627{
628 int rc = 0, opcode, ahslen;
629 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
630 struct iscsi_task *task;
631
632
633 tcp_conn->in.datalen = ntoh24(hdr->dlength);
634 if (tcp_conn->in.datalen > conn->max_recv_dlength) {
635 iscsi_conn_printk(KERN_ERR, conn,
636 "iscsi_tcp: datalen %d > %d\n",
637 tcp_conn->in.datalen, conn->max_recv_dlength);
638 return ISCSI_ERR_DATALEN;
639 }
640
641
642
643
644 ahslen = hdr->hlength << 2;
645
646 opcode = hdr->opcode & ISCSI_OPCODE_MASK;
647
648 rc = iscsi_verify_itt(conn, hdr->itt);
649 if (rc)
650 return rc;
651
652 ISCSI_DBG_TCP(conn, "opcode 0x%x ahslen %d datalen %d\n",
653 opcode, ahslen, tcp_conn->in.datalen);
654
655 switch(opcode) {
656 case ISCSI_OP_SCSI_DATA_IN:
657 spin_lock(&conn->session->lock);
658 task = iscsi_itt_to_ctask(conn, hdr->itt);
659 if (!task)
660 rc = ISCSI_ERR_BAD_ITT;
661 else
662 rc = iscsi_tcp_data_in(conn, task);
663 if (rc) {
664 spin_unlock(&conn->session->lock);
665 break;
666 }
667
668 if (tcp_conn->in.datalen) {
669 struct iscsi_tcp_task *tcp_task = task->dd_data;
670 struct hash_desc *rx_hash = NULL;
671 struct scsi_data_buffer *sdb = scsi_in(task->sc);
672
673
674
675
676
677
678
679
680
681 if (conn->datadgst_en &&
682 !(conn->session->tt->caps & CAP_DIGEST_OFFLOAD))
683 rx_hash = tcp_conn->rx_hash;
684
685 ISCSI_DBG_TCP(conn, "iscsi_tcp_begin_data_in( "
686 "offset=%d, datalen=%d)\n",
687 tcp_task->data_offset,
688 tcp_conn->in.datalen);
689 task->last_xfer = jiffies;
690 rc = iscsi_segment_seek_sg(&tcp_conn->in.segment,
691 sdb->table.sgl,
692 sdb->table.nents,
693 tcp_task->data_offset,
694 tcp_conn->in.datalen,
695 iscsi_tcp_process_data_in,
696 rx_hash);
697 spin_unlock(&conn->session->lock);
698 return rc;
699 }
700 rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
701 spin_unlock(&conn->session->lock);
702 break;
703 case ISCSI_OP_SCSI_CMD_RSP:
704 if (tcp_conn->in.datalen) {
705 iscsi_tcp_data_recv_prep(tcp_conn);
706 return 0;
707 }
708 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
709 break;
710 case ISCSI_OP_R2T:
711 spin_lock(&conn->session->lock);
712 task = iscsi_itt_to_ctask(conn, hdr->itt);
713 if (!task)
714 rc = ISCSI_ERR_BAD_ITT;
715 else if (ahslen)
716 rc = ISCSI_ERR_AHSLEN;
717 else if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
718 task->last_xfer = jiffies;
719 rc = iscsi_tcp_r2t_rsp(conn, task);
720 } else
721 rc = ISCSI_ERR_PROTO;
722 spin_unlock(&conn->session->lock);
723 break;
724 case ISCSI_OP_LOGIN_RSP:
725 case ISCSI_OP_TEXT_RSP:
726 case ISCSI_OP_REJECT:
727 case ISCSI_OP_ASYNC_EVENT:
728
729
730
731
732
733 if (ISCSI_DEF_MAX_RECV_SEG_LEN < tcp_conn->in.datalen) {
734 iscsi_conn_printk(KERN_ERR, conn,
735 "iscsi_tcp: received buffer of "
736 "len %u but conn buffer is only %u "
737 "(opcode %0x)\n",
738 tcp_conn->in.datalen,
739 ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);
740 rc = ISCSI_ERR_PROTO;
741 break;
742 }
743
744
745
746
747 if (tcp_conn->in.datalen) {
748 iscsi_tcp_data_recv_prep(tcp_conn);
749 return 0;
750 }
751
752 case ISCSI_OP_LOGOUT_RSP:
753 case ISCSI_OP_NOOP_IN:
754 case ISCSI_OP_SCSI_TMFUNC_RSP:
755 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
756 break;
757 default:
758 rc = ISCSI_ERR_BAD_OPCODE;
759 break;
760 }
761
762 if (rc == 0) {
763
764
765 if (tcp_conn->in.datalen)
766 return ISCSI_ERR_PROTO;
767 iscsi_tcp_hdr_recv_prep(tcp_conn);
768 }
769
770 return rc;
771}
772
773
774
775
776
777
778
779
780static int
781iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
782 struct iscsi_segment *segment)
783{
784 struct iscsi_conn *conn = tcp_conn->iscsi_conn;
785 struct iscsi_hdr *hdr;
786
787
788
789
790
791 hdr = (struct iscsi_hdr *) tcp_conn->in.hdr_buf;
792 if (segment->copied == sizeof(struct iscsi_hdr) && hdr->hlength) {
793
794
795
796 unsigned int ahslen = hdr->hlength << 2;
797
798
799 if (sizeof(*hdr) + ahslen > sizeof(tcp_conn->in.hdr_buf))
800 return ISCSI_ERR_AHSLEN;
801
802 segment->total_size += ahslen;
803 segment->size += ahslen;
804 return 0;
805 }
806
807
808
809
810 if (conn->hdrdgst_en &&
811 !(conn->session->tt->caps & CAP_DIGEST_OFFLOAD)) {
812 if (segment->digest_len == 0) {
813
814
815
816
817
818 iscsi_tcp_segment_splice_digest(segment,
819 segment->recv_digest);
820 return 0;
821 }
822
823 iscsi_tcp_dgst_header(tcp_conn->rx_hash, hdr,
824 segment->total_copied - ISCSI_DIGEST_SIZE,
825 segment->digest);
826
827 if (!iscsi_tcp_dgst_verify(tcp_conn, segment))
828 return ISCSI_ERR_HDR_DGST;
829 }
830
831 tcp_conn->in.hdr = hdr;
832 return iscsi_tcp_hdr_dissect(conn, hdr);
833}
834
835
836
837
838
839
840
841
842inline int iscsi_tcp_recv_segment_is_hdr(struct iscsi_tcp_conn *tcp_conn)
843{
844 return tcp_conn->in.segment.done == iscsi_tcp_hdr_recv_done;
845}
846EXPORT_SYMBOL_GPL(iscsi_tcp_recv_segment_is_hdr);
847
848
849
850
851
852
853
854
855
856
857
858int iscsi_tcp_recv_skb(struct iscsi_conn *conn, struct sk_buff *skb,
859 unsigned int offset, bool offloaded, int *status)
860{
861 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
862 struct iscsi_segment *segment = &tcp_conn->in.segment;
863 struct skb_seq_state seq;
864 unsigned int consumed = 0;
865 int rc = 0;
866
867 ISCSI_DBG_TCP(conn, "in %d bytes\n", skb->len - offset);
868
869
870
871
872
873 conn->last_recv = jiffies;
874
875 if (unlikely(conn->suspend_rx)) {
876 ISCSI_DBG_TCP(conn, "Rx suspended!\n");
877 *status = ISCSI_TCP_SUSPENDED;
878 return 0;
879 }
880
881 if (offloaded) {
882 segment->total_copied = segment->total_size;
883 goto segment_done;
884 }
885
886 skb_prepare_seq_read(skb, offset, skb->len, &seq);
887 while (1) {
888 unsigned int avail;
889 const u8 *ptr;
890
891 avail = skb_seq_read(consumed, &ptr, &seq);
892 if (avail == 0) {
893 ISCSI_DBG_TCP(conn, "no more data avail. Consumed %d\n",
894 consumed);
895 *status = ISCSI_TCP_SKB_DONE;
896 skb_abort_seq_read(&seq);
897 goto skb_done;
898 }
899 BUG_ON(segment->copied >= segment->size);
900
901 ISCSI_DBG_TCP(conn, "skb %p ptr=%p avail=%u\n", skb, ptr,
902 avail);
903 rc = iscsi_tcp_segment_recv(tcp_conn, segment, ptr, avail);
904 BUG_ON(rc == 0);
905 consumed += rc;
906
907 if (segment->total_copied >= segment->total_size) {
908 skb_abort_seq_read(&seq);
909 goto segment_done;
910 }
911 }
912
913segment_done:
914 *status = ISCSI_TCP_SEGMENT_DONE;
915 ISCSI_DBG_TCP(conn, "segment done\n");
916 rc = segment->done(tcp_conn, segment);
917 if (rc != 0) {
918 *status = ISCSI_TCP_CONN_ERR;
919 ISCSI_DBG_TCP(conn, "Error receiving PDU, errno=%d\n", rc);
920 iscsi_conn_failure(conn, rc);
921 return 0;
922 }
923
924
925skb_done:
926 conn->rxdata_octets += consumed;
927 return consumed;
928}
929EXPORT_SYMBOL_GPL(iscsi_tcp_recv_skb);
930
931
932
933
934
935
936
937int iscsi_tcp_task_init(struct iscsi_task *task)
938{
939 struct iscsi_tcp_task *tcp_task = task->dd_data;
940 struct iscsi_conn *conn = task->conn;
941 struct scsi_cmnd *sc = task->sc;
942 int err;
943
944 if (!sc) {
945
946
947
948
949 ISCSI_DBG_TCP(conn, "mtask deq [itt 0x%x]\n", task->itt);
950
951 return conn->session->tt->init_pdu(task, 0, task->data_count);
952 }
953
954 BUG_ON(__kfifo_len(tcp_task->r2tqueue));
955 tcp_task->exp_datasn = 0;
956
957
958 ISCSI_DBG_TCP(conn, "task deq [itt 0x%x imm %d unsol %d]\n",
959 task->itt, task->imm_count, task->unsol_r2t.data_length);
960
961 err = conn->session->tt->init_pdu(task, 0, task->imm_count);
962 if (err)
963 return err;
964 task->imm_count = 0;
965 return 0;
966}
967EXPORT_SYMBOL_GPL(iscsi_tcp_task_init);
968
969static struct iscsi_r2t_info *iscsi_tcp_get_curr_r2t(struct iscsi_task *task)
970{
971 struct iscsi_session *session = task->conn->session;
972 struct iscsi_tcp_task *tcp_task = task->dd_data;
973 struct iscsi_r2t_info *r2t = NULL;
974
975 if (iscsi_task_has_unsol_data(task))
976 r2t = &task->unsol_r2t;
977 else {
978 spin_lock_bh(&session->lock);
979 if (tcp_task->r2t) {
980 r2t = tcp_task->r2t;
981
982 if (r2t->data_length <= r2t->sent) {
983 ISCSI_DBG_TCP(task->conn,
984 " done with r2t %p\n", r2t);
985 __kfifo_put(tcp_task->r2tpool.queue,
986 (void *)&tcp_task->r2t,
987 sizeof(void *));
988 tcp_task->r2t = r2t = NULL;
989 }
990 }
991
992 if (r2t == NULL) {
993 __kfifo_get(tcp_task->r2tqueue,
994 (void *)&tcp_task->r2t, sizeof(void *));
995 r2t = tcp_task->r2t;
996 }
997 spin_unlock_bh(&session->lock);
998 }
999
1000 return r2t;
1001}
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011int iscsi_tcp_task_xmit(struct iscsi_task *task)
1012{
1013 struct iscsi_conn *conn = task->conn;
1014 struct iscsi_session *session = conn->session;
1015 struct iscsi_r2t_info *r2t;
1016 int rc = 0;
1017
1018flush:
1019
1020 rc = session->tt->xmit_pdu(task);
1021 if (rc < 0)
1022 return rc;
1023
1024
1025 if (!task->sc) {
1026 if (task->hdr->itt == RESERVED_ITT)
1027 iscsi_put_task(task);
1028 return 0;
1029 }
1030
1031
1032 if (task->sc->sc_data_direction != DMA_TO_DEVICE)
1033 return 0;
1034
1035 r2t = iscsi_tcp_get_curr_r2t(task);
1036 if (r2t == NULL) {
1037
1038 ISCSI_DBG_TCP(conn, "no R2Ts yet\n");
1039 return 0;
1040 }
1041
1042 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_DATA_OUT);
1043 if (rc)
1044 return rc;
1045 iscsi_prep_data_out_pdu(task, r2t, (struct iscsi_data *) task->hdr);
1046
1047 ISCSI_DBG_TCP(conn, "sol dout %p [dsn %d itt 0x%x doff %d dlen %d]\n",
1048 r2t, r2t->datasn - 1, task->hdr->itt,
1049 r2t->data_offset + r2t->sent, r2t->data_count);
1050
1051 rc = conn->session->tt->init_pdu(task, r2t->data_offset + r2t->sent,
1052 r2t->data_count);
1053 if (rc) {
1054 iscsi_conn_failure(conn, ISCSI_ERR_XMIT_FAILED);
1055 return rc;
1056 }
1057
1058 r2t->sent += r2t->data_count;
1059 goto flush;
1060}
1061EXPORT_SYMBOL_GPL(iscsi_tcp_task_xmit);
1062
1063struct iscsi_cls_conn *
1064iscsi_tcp_conn_setup(struct iscsi_cls_session *cls_session, int dd_data_size,
1065 uint32_t conn_idx)
1066
1067{
1068 struct iscsi_conn *conn;
1069 struct iscsi_cls_conn *cls_conn;
1070 struct iscsi_tcp_conn *tcp_conn;
1071
1072 cls_conn = iscsi_conn_setup(cls_session, sizeof(*tcp_conn), conn_idx);
1073 if (!cls_conn)
1074 return NULL;
1075 conn = cls_conn->dd_data;
1076
1077
1078
1079
1080 conn->max_recv_dlength = ISCSI_DEF_MAX_RECV_SEG_LEN;
1081
1082 tcp_conn = conn->dd_data;
1083 tcp_conn->iscsi_conn = conn;
1084
1085 tcp_conn->dd_data = kzalloc(dd_data_size, GFP_KERNEL);
1086 if (!tcp_conn->dd_data) {
1087 iscsi_conn_teardown(cls_conn);
1088 return NULL;
1089 }
1090 return cls_conn;
1091}
1092EXPORT_SYMBOL_GPL(iscsi_tcp_conn_setup);
1093
1094void iscsi_tcp_conn_teardown(struct iscsi_cls_conn *cls_conn)
1095{
1096 struct iscsi_conn *conn = cls_conn->dd_data;
1097 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1098
1099 kfree(tcp_conn->dd_data);
1100 iscsi_conn_teardown(cls_conn);
1101}
1102EXPORT_SYMBOL_GPL(iscsi_tcp_conn_teardown);
1103
1104int iscsi_tcp_r2tpool_alloc(struct iscsi_session *session)
1105{
1106 int i;
1107 int cmd_i;
1108
1109
1110
1111
1112 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1113 struct iscsi_task *task = session->cmds[cmd_i];
1114 struct iscsi_tcp_task *tcp_task = task->dd_data;
1115
1116
1117
1118
1119
1120
1121
1122
1123 if (iscsi_pool_init(&tcp_task->r2tpool,
1124 session->max_r2t * 2, NULL,
1125 sizeof(struct iscsi_r2t_info))) {
1126 goto r2t_alloc_fail;
1127 }
1128
1129
1130 tcp_task->r2tqueue = kfifo_alloc(
1131 session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
1132 if (tcp_task->r2tqueue == ERR_PTR(-ENOMEM)) {
1133 iscsi_pool_free(&tcp_task->r2tpool);
1134 goto r2t_alloc_fail;
1135 }
1136 }
1137
1138 return 0;
1139
1140r2t_alloc_fail:
1141 for (i = 0; i < cmd_i; i++) {
1142 struct iscsi_task *task = session->cmds[i];
1143 struct iscsi_tcp_task *tcp_task = task->dd_data;
1144
1145 kfifo_free(tcp_task->r2tqueue);
1146 iscsi_pool_free(&tcp_task->r2tpool);
1147 }
1148 return -ENOMEM;
1149}
1150EXPORT_SYMBOL_GPL(iscsi_tcp_r2tpool_alloc);
1151
1152void iscsi_tcp_r2tpool_free(struct iscsi_session *session)
1153{
1154 int i;
1155
1156 for (i = 0; i < session->cmds_max; i++) {
1157 struct iscsi_task *task = session->cmds[i];
1158 struct iscsi_tcp_task *tcp_task = task->dd_data;
1159
1160 kfifo_free(tcp_task->r2tqueue);
1161 iscsi_pool_free(&tcp_task->r2tpool);
1162 }
1163}
1164EXPORT_SYMBOL_GPL(iscsi_tcp_r2tpool_free);
1165
1166void iscsi_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn,
1167 struct iscsi_stats *stats)
1168{
1169 struct iscsi_conn *conn = cls_conn->dd_data;
1170
1171 stats->txdata_octets = conn->txdata_octets;
1172 stats->rxdata_octets = conn->rxdata_octets;
1173 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
1174 stats->dataout_pdus = conn->dataout_pdus_cnt;
1175 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
1176 stats->datain_pdus = conn->datain_pdus_cnt;
1177 stats->r2t_pdus = conn->r2t_pdus_cnt;
1178 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
1179 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
1180}
1181EXPORT_SYMBOL_GPL(iscsi_tcp_conn_get_stats);
1182