[POWERPC] Only offer CONFIG_BRIQ_PANEL if CONFIG_PPC_CHRP is enabled
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / scsi / iscsi_tcp.c
1 /*
2 * iSCSI Initiator over TCP/IP Data-Path
3 *
4 * Copyright (C) 2004 Dmitry Yusupov
5 * Copyright (C) 2004 Alex Aizman
6 * Copyright (C) 2005 - 2006 Mike Christie
7 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
8 * maintained by open-iscsi@googlegroups.com
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published
12 * by the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * See the file COPYING included with this distribution for more details.
21 *
22 * Credits:
23 * Christoph Hellwig
24 * FUJITA Tomonori
25 * Arne Redlich
26 * Zhenyu Wang
27 */
28
29 #include <linux/types.h>
30 #include <linux/list.h>
31 #include <linux/inet.h>
32 #include <linux/blkdev.h>
33 #include <linux/crypto.h>
34 #include <linux/delay.h>
35 #include <linux/kfifo.h>
36 #include <linux/scatterlist.h>
37 #include <linux/mutex.h>
38 #include <net/tcp.h>
39 #include <scsi/scsi_cmnd.h>
40 #include <scsi/scsi_host.h>
41 #include <scsi/scsi.h>
42 #include <scsi/scsi_transport_iscsi.h>
43
44 #include "iscsi_tcp.h"
45
46 #define ISCSI_TCP_VERSION "1.0-595"
47
48 MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
49 "Alex Aizman <itn780@yahoo.com>");
50 MODULE_DESCRIPTION("iSCSI/TCP data-path");
51 MODULE_LICENSE("GPL");
52 MODULE_VERSION(ISCSI_TCP_VERSION);
53 /* #define DEBUG_TCP */
54 #define DEBUG_ASSERT
55
56 #ifdef DEBUG_TCP
57 #define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
58 #else
59 #define debug_tcp(fmt...)
60 #endif
61
62 #ifndef DEBUG_ASSERT
63 #ifdef BUG_ON
64 #undef BUG_ON
65 #endif
66 #define BUG_ON(expr)
67 #endif
68
69 static unsigned int iscsi_max_lun = 512;
70 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
71
72 static inline void
73 iscsi_buf_init_iov(struct iscsi_buf *ibuf, char *vbuf, int size)
74 {
75 ibuf->sg.page = virt_to_page(vbuf);
76 ibuf->sg.offset = offset_in_page(vbuf);
77 ibuf->sg.length = size;
78 ibuf->sent = 0;
79 ibuf->use_sendmsg = 1;
80 }
81
82 static inline void
83 iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
84 {
85 ibuf->sg.page = sg->page;
86 ibuf->sg.offset = sg->offset;
87 ibuf->sg.length = sg->length;
88 /*
89 * Fastpath: sg element fits into single page
90 */
91 if (sg->length + sg->offset <= PAGE_SIZE && !PageSlab(sg->page))
92 ibuf->use_sendmsg = 0;
93 else
94 ibuf->use_sendmsg = 1;
95 ibuf->sent = 0;
96 }
97
98 static inline int
99 iscsi_buf_left(struct iscsi_buf *ibuf)
100 {
101 int rc;
102
103 rc = ibuf->sg.length - ibuf->sent;
104 BUG_ON(rc < 0);
105 return rc;
106 }
107
108 static inline void
109 iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
110 u8* crc)
111 {
112 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
113
114 crypto_digest_digest(tcp_conn->tx_tfm, &buf->sg, 1, crc);
115 buf->sg.length += sizeof(uint32_t);
116 }
117
118 static inline int
119 iscsi_hdr_extract(struct iscsi_tcp_conn *tcp_conn)
120 {
121 struct sk_buff *skb = tcp_conn->in.skb;
122
123 tcp_conn->in.zero_copy_hdr = 0;
124
125 if (tcp_conn->in.copy >= tcp_conn->hdr_size &&
126 tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER) {
127 /*
128 * Zero-copy PDU Header: using connection context
129 * to store header pointer.
130 */
131 if (skb_shinfo(skb)->frag_list == NULL &&
132 !skb_shinfo(skb)->nr_frags) {
133 tcp_conn->in.hdr = (struct iscsi_hdr *)
134 ((char*)skb->data + tcp_conn->in.offset);
135 tcp_conn->in.zero_copy_hdr = 1;
136 } else {
137 /* ignoring return code since we checked
138 * in.copy before */
139 skb_copy_bits(skb, tcp_conn->in.offset,
140 &tcp_conn->hdr, tcp_conn->hdr_size);
141 tcp_conn->in.hdr = &tcp_conn->hdr;
142 }
143 tcp_conn->in.offset += tcp_conn->hdr_size;
144 tcp_conn->in.copy -= tcp_conn->hdr_size;
145 } else {
146 int hdr_remains;
147 int copylen;
148
149 /*
150 * PDU header scattered across SKB's,
151 * copying it... This'll happen quite rarely.
152 */
153
154 if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER)
155 tcp_conn->in.hdr_offset = 0;
156
157 hdr_remains = tcp_conn->hdr_size - tcp_conn->in.hdr_offset;
158 BUG_ON(hdr_remains <= 0);
159
160 copylen = min(tcp_conn->in.copy, hdr_remains);
161 skb_copy_bits(skb, tcp_conn->in.offset,
162 (char*)&tcp_conn->hdr + tcp_conn->in.hdr_offset,
163 copylen);
164
165 debug_tcp("PDU gather offset %d bytes %d in.offset %d "
166 "in.copy %d\n", tcp_conn->in.hdr_offset, copylen,
167 tcp_conn->in.offset, tcp_conn->in.copy);
168
169 tcp_conn->in.offset += copylen;
170 tcp_conn->in.copy -= copylen;
171 if (copylen < hdr_remains) {
172 tcp_conn->in_progress = IN_PROGRESS_HEADER_GATHER;
173 tcp_conn->in.hdr_offset += copylen;
174 return -EAGAIN;
175 }
176 tcp_conn->in.hdr = &tcp_conn->hdr;
177 tcp_conn->discontiguous_hdr_cnt++;
178 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
179 }
180
181 return 0;
182 }
183
184 /*
185 * must be called with session lock
186 */
187 static void
188 __iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
189 {
190 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
191 struct scsi_cmnd *sc;
192
193 sc = ctask->sc;
194 if (unlikely(!sc))
195 return;
196
197 tcp_ctask->xmstate = XMSTATE_IDLE;
198 tcp_ctask->r2t = NULL;
199 }
200
201 /**
202 * iscsi_data_rsp - SCSI Data-In Response processing
203 * @conn: iscsi connection
204 * @ctask: scsi command task
205 **/
206 static int
207 iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
208 {
209 int rc;
210 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
211 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
212 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
213 struct iscsi_session *session = conn->session;
214 int datasn = be32_to_cpu(rhdr->datasn);
215
216 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
217 if (rc)
218 return rc;
219 /*
220 * setup Data-In byte counter (gets decremented..)
221 */
222 ctask->data_count = tcp_conn->in.datalen;
223
224 if (tcp_conn->in.datalen == 0)
225 return 0;
226
227 if (ctask->datasn != datasn)
228 return ISCSI_ERR_DATASN;
229
230 ctask->datasn++;
231
232 tcp_ctask->data_offset = be32_to_cpu(rhdr->offset);
233 if (tcp_ctask->data_offset + tcp_conn->in.datalen > ctask->total_length)
234 return ISCSI_ERR_DATA_OFFSET;
235
236 if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
237 struct scsi_cmnd *sc = ctask->sc;
238
239 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
240 if (rhdr->flags & ISCSI_FLAG_DATA_UNDERFLOW) {
241 int res_count = be32_to_cpu(rhdr->residual_count);
242
243 if (res_count > 0 &&
244 res_count <= sc->request_bufflen) {
245 sc->resid = res_count;
246 sc->result = (DID_OK << 16) | rhdr->cmd_status;
247 } else
248 sc->result = (DID_BAD_TARGET << 16) |
249 rhdr->cmd_status;
250 } else if (rhdr->flags & ISCSI_FLAG_DATA_OVERFLOW) {
251 sc->resid = be32_to_cpu(rhdr->residual_count);
252 sc->result = (DID_OK << 16) | rhdr->cmd_status;
253 } else
254 sc->result = (DID_OK << 16) | rhdr->cmd_status;
255 }
256
257 conn->datain_pdus_cnt++;
258 return 0;
259 }
260
261 /**
262 * iscsi_solicit_data_init - initialize first Data-Out
263 * @conn: iscsi connection
264 * @ctask: scsi command task
265 * @r2t: R2T info
266 *
267 * Notes:
268 * Initialize first Data-Out within this R2T sequence and finds
269 * proper data_offset within this SCSI command.
270 *
271 * This function is called with connection lock taken.
272 **/
273 static void
274 iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
275 struct iscsi_r2t_info *r2t)
276 {
277 struct iscsi_data *hdr;
278 struct scsi_cmnd *sc = ctask->sc;
279 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
280
281 hdr = &r2t->dtask.hdr;
282 memset(hdr, 0, sizeof(struct iscsi_data));
283 hdr->ttt = r2t->ttt;
284 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
285 r2t->solicit_datasn++;
286 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
287 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
288 hdr->itt = ctask->hdr->itt;
289 hdr->exp_statsn = r2t->exp_statsn;
290 hdr->offset = cpu_to_be32(r2t->data_offset);
291 if (r2t->data_length > conn->max_xmit_dlength) {
292 hton24(hdr->dlength, conn->max_xmit_dlength);
293 r2t->data_count = conn->max_xmit_dlength;
294 hdr->flags = 0;
295 } else {
296 hton24(hdr->dlength, r2t->data_length);
297 r2t->data_count = r2t->data_length;
298 hdr->flags = ISCSI_FLAG_CMD_FINAL;
299 }
300 conn->dataout_pdus_cnt++;
301
302 r2t->sent = 0;
303
304 iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
305 sizeof(struct iscsi_hdr));
306
307 if (sc->use_sg) {
308 int i, sg_count = 0;
309 struct scatterlist *sg = sc->request_buffer;
310
311 r2t->sg = NULL;
312 for (i = 0; i < sc->use_sg; i++, sg += 1) {
313 /* FIXME: prefetch ? */
314 if (sg_count + sg->length > r2t->data_offset) {
315 int page_offset;
316
317 /* sg page found! */
318
319 /* offset within this page */
320 page_offset = r2t->data_offset - sg_count;
321
322 /* fill in this buffer */
323 iscsi_buf_init_sg(&r2t->sendbuf, sg);
324 r2t->sendbuf.sg.offset += page_offset;
325 r2t->sendbuf.sg.length -= page_offset;
326
327 /* xmit logic will continue with next one */
328 r2t->sg = sg + 1;
329 break;
330 }
331 sg_count += sg->length;
332 }
333 BUG_ON(r2t->sg == NULL);
334 } else
335 iscsi_buf_init_iov(&tcp_ctask->sendbuf,
336 (char*)sc->request_buffer + r2t->data_offset,
337 r2t->data_count);
338 }
339
340 /**
341 * iscsi_r2t_rsp - iSCSI R2T Response processing
342 * @conn: iscsi connection
343 * @ctask: scsi command task
344 **/
345 static int
346 iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
347 {
348 struct iscsi_r2t_info *r2t;
349 struct iscsi_session *session = conn->session;
350 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
351 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
352 struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
353 int r2tsn = be32_to_cpu(rhdr->r2tsn);
354 int rc;
355
356 if (tcp_conn->in.datalen)
357 return ISCSI_ERR_DATALEN;
358
359 if (tcp_ctask->exp_r2tsn && tcp_ctask->exp_r2tsn != r2tsn)
360 return ISCSI_ERR_R2TSN;
361
362 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
363 if (rc)
364 return rc;
365
366 /* FIXME: use R2TSN to detect missing R2T */
367
368 /* fill-in new R2T associated with the task */
369 spin_lock(&session->lock);
370 if (!ctask->sc || ctask->mtask ||
371 session->state != ISCSI_STATE_LOGGED_IN) {
372 printk(KERN_INFO "iscsi_tcp: dropping R2T itt %d in "
373 "recovery...\n", ctask->itt);
374 spin_unlock(&session->lock);
375 return 0;
376 }
377 rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
378 BUG_ON(!rc);
379
380 r2t->exp_statsn = rhdr->statsn;
381 r2t->data_length = be32_to_cpu(rhdr->data_length);
382 if (r2t->data_length == 0 ||
383 r2t->data_length > session->max_burst) {
384 spin_unlock(&session->lock);
385 return ISCSI_ERR_DATALEN;
386 }
387
388 r2t->data_offset = be32_to_cpu(rhdr->data_offset);
389 if (r2t->data_offset + r2t->data_length > ctask->total_length) {
390 spin_unlock(&session->lock);
391 return ISCSI_ERR_DATALEN;
392 }
393
394 r2t->ttt = rhdr->ttt; /* no flip */
395 r2t->solicit_datasn = 0;
396
397 iscsi_solicit_data_init(conn, ctask, r2t);
398
399 tcp_ctask->exp_r2tsn = r2tsn + 1;
400 tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
401 __kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
402 __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
403
404 scsi_queue_work(session->host, &conn->xmitwork);
405 conn->r2t_pdus_cnt++;
406 spin_unlock(&session->lock);
407
408 return 0;
409 }
410
411 static int
412 iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
413 {
414 int rc = 0, opcode, ahslen;
415 struct iscsi_hdr *hdr;
416 struct iscsi_session *session = conn->session;
417 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
418 uint32_t cdgst, rdgst = 0, itt;
419
420 hdr = tcp_conn->in.hdr;
421
422 /* verify PDU length */
423 tcp_conn->in.datalen = ntoh24(hdr->dlength);
424 if (tcp_conn->in.datalen > conn->max_recv_dlength) {
425 printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
426 tcp_conn->in.datalen, conn->max_recv_dlength);
427 return ISCSI_ERR_DATALEN;
428 }
429 tcp_conn->data_copied = 0;
430
431 /* read AHS */
432 ahslen = hdr->hlength << 2;
433 tcp_conn->in.offset += ahslen;
434 tcp_conn->in.copy -= ahslen;
435 if (tcp_conn->in.copy < 0) {
436 printk(KERN_ERR "iscsi_tcp: can't handle AHS with length "
437 "%d bytes\n", ahslen);
438 return ISCSI_ERR_AHSLEN;
439 }
440
441 /* calculate read padding */
442 tcp_conn->in.padding = tcp_conn->in.datalen & (ISCSI_PAD_LEN-1);
443 if (tcp_conn->in.padding) {
444 tcp_conn->in.padding = ISCSI_PAD_LEN - tcp_conn->in.padding;
445 debug_scsi("read padding %d bytes\n", tcp_conn->in.padding);
446 }
447
448 if (conn->hdrdgst_en) {
449 struct scatterlist sg;
450
451 sg_init_one(&sg, (u8 *)hdr,
452 sizeof(struct iscsi_hdr) + ahslen);
453 crypto_digest_digest(tcp_conn->rx_tfm, &sg, 1, (u8 *)&cdgst);
454 rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
455 ahslen);
456 if (cdgst != rdgst) {
457 printk(KERN_ERR "iscsi_tcp: hdrdgst error "
458 "recv 0x%x calc 0x%x\n", rdgst, cdgst);
459 return ISCSI_ERR_HDR_DGST;
460 }
461 }
462
463 opcode = hdr->opcode & ISCSI_OPCODE_MASK;
464 /* verify itt (itt encoding: age+cid+itt) */
465 rc = iscsi_verify_itt(conn, hdr, &itt);
466 if (rc == ISCSI_ERR_NO_SCSI_CMD) {
467 tcp_conn->in.datalen = 0; /* force drop */
468 return 0;
469 } else if (rc)
470 return rc;
471
472 debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
473 opcode, tcp_conn->in.offset, tcp_conn->in.copy,
474 ahslen, tcp_conn->in.datalen);
475
476 switch(opcode) {
477 case ISCSI_OP_SCSI_DATA_IN:
478 tcp_conn->in.ctask = session->cmds[itt];
479 rc = iscsi_data_rsp(conn, tcp_conn->in.ctask);
480 /* fall through */
481 case ISCSI_OP_SCSI_CMD_RSP:
482 tcp_conn->in.ctask = session->cmds[itt];
483 if (tcp_conn->in.datalen)
484 goto copy_hdr;
485
486 spin_lock(&session->lock);
487 __iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
488 rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
489 spin_unlock(&session->lock);
490 break;
491 case ISCSI_OP_R2T:
492 tcp_conn->in.ctask = session->cmds[itt];
493 if (ahslen)
494 rc = ISCSI_ERR_AHSLEN;
495 else if (tcp_conn->in.ctask->sc->sc_data_direction ==
496 DMA_TO_DEVICE)
497 rc = iscsi_r2t_rsp(conn, tcp_conn->in.ctask);
498 else
499 rc = ISCSI_ERR_PROTO;
500 break;
501 case ISCSI_OP_LOGIN_RSP:
502 case ISCSI_OP_TEXT_RSP:
503 case ISCSI_OP_LOGOUT_RSP:
504 case ISCSI_OP_NOOP_IN:
505 case ISCSI_OP_REJECT:
506 case ISCSI_OP_ASYNC_EVENT:
507 if (tcp_conn->in.datalen)
508 goto copy_hdr;
509 /* fall through */
510 case ISCSI_OP_SCSI_TMFUNC_RSP:
511 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
512 break;
513 default:
514 rc = ISCSI_ERR_BAD_OPCODE;
515 break;
516 }
517
518 return rc;
519
520 copy_hdr:
521 /*
522 * if we did zero copy for the header but we will need multiple
523 * skbs to complete the command then we have to copy the header
524 * for later use
525 */
526 if (tcp_conn->in.zero_copy_hdr && tcp_conn->in.copy <
527 (tcp_conn->in.datalen + tcp_conn->in.padding +
528 (conn->datadgst_en ? 4 : 0))) {
529 debug_tcp("Copying header for later use. in.copy %d in.datalen"
530 " %d\n", tcp_conn->in.copy, tcp_conn->in.datalen);
531 memcpy(&tcp_conn->hdr, tcp_conn->in.hdr,
532 sizeof(struct iscsi_hdr));
533 tcp_conn->in.hdr = &tcp_conn->hdr;
534 tcp_conn->in.zero_copy_hdr = 0;
535 }
536 return 0;
537 }
538
539 /**
540 * iscsi_ctask_copy - copy skb bits to the destanation cmd task
541 * @conn: iscsi tcp connection
542 * @ctask: scsi command task
543 * @buf: buffer to copy to
544 * @buf_size: size of buffer
545 * @offset: offset within the buffer
546 *
547 * Notes:
548 * The function calls skb_copy_bits() and updates per-connection and
549 * per-cmd byte counters.
550 *
551 * Read counters (in bytes):
552 *
553 * conn->in.offset offset within in progress SKB
554 * conn->in.copy left to copy from in progress SKB
555 * including padding
556 * conn->in.copied copied already from in progress SKB
557 * conn->data_copied copied already from in progress buffer
558 * ctask->sent total bytes sent up to the MidLayer
559 * ctask->data_count left to copy from in progress Data-In
560 * buf_left left to copy from in progress buffer
561 **/
562 static inline int
563 iscsi_ctask_copy(struct iscsi_tcp_conn *tcp_conn, struct iscsi_cmd_task *ctask,
564 void *buf, int buf_size, int offset)
565 {
566 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
567 int buf_left = buf_size - (tcp_conn->data_copied + offset);
568 int size = min(tcp_conn->in.copy, buf_left);
569 int rc;
570
571 size = min(size, ctask->data_count);
572
573 debug_tcp("ctask_copy %d bytes at offset %d copied %d\n",
574 size, tcp_conn->in.offset, tcp_conn->in.copied);
575
576 BUG_ON(size <= 0);
577 BUG_ON(tcp_ctask->sent + size > ctask->total_length);
578
579 rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
580 (char*)buf + (offset + tcp_conn->data_copied), size);
581 /* must fit into skb->len */
582 BUG_ON(rc);
583
584 tcp_conn->in.offset += size;
585 tcp_conn->in.copy -= size;
586 tcp_conn->in.copied += size;
587 tcp_conn->data_copied += size;
588 tcp_ctask->sent += size;
589 ctask->data_count -= size;
590
591 BUG_ON(tcp_conn->in.copy < 0);
592 BUG_ON(ctask->data_count < 0);
593
594 if (buf_size != (tcp_conn->data_copied + offset)) {
595 if (!ctask->data_count) {
596 BUG_ON(buf_size - tcp_conn->data_copied < 0);
597 /* done with this PDU */
598 return buf_size - tcp_conn->data_copied;
599 }
600 return -EAGAIN;
601 }
602
603 /* done with this buffer or with both - PDU and buffer */
604 tcp_conn->data_copied = 0;
605 return 0;
606 }
607
608 /**
609 * iscsi_tcp_copy - copy skb bits to the destanation buffer
610 * @conn: iscsi tcp connection
611 *
612 * Notes:
613 * The function calls skb_copy_bits() and updates per-connection
614 * byte counters.
615 **/
616 static inline int
617 iscsi_tcp_copy(struct iscsi_tcp_conn *tcp_conn)
618 {
619 void *buf = tcp_conn->data;
620 int buf_size = tcp_conn->in.datalen;
621 int buf_left = buf_size - tcp_conn->data_copied;
622 int size = min(tcp_conn->in.copy, buf_left);
623 int rc;
624
625 debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
626 size, tcp_conn->in.offset, tcp_conn->data_copied);
627 BUG_ON(size <= 0);
628
629 rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
630 (char*)buf + tcp_conn->data_copied, size);
631 BUG_ON(rc);
632
633 tcp_conn->in.offset += size;
634 tcp_conn->in.copy -= size;
635 tcp_conn->in.copied += size;
636 tcp_conn->data_copied += size;
637
638 if (buf_size != tcp_conn->data_copied)
639 return -EAGAIN;
640
641 return 0;
642 }
643
644 static inline void
645 partial_sg_digest_update(struct iscsi_tcp_conn *tcp_conn,
646 struct scatterlist *sg, int offset, int length)
647 {
648 struct scatterlist temp;
649
650 memcpy(&temp, sg, sizeof(struct scatterlist));
651 temp.offset = offset;
652 temp.length = length;
653 crypto_digest_update(tcp_conn->data_rx_tfm, &temp, 1);
654 }
655
656 static void
657 iscsi_recv_digest_update(struct iscsi_tcp_conn *tcp_conn, char* buf, int len)
658 {
659 struct scatterlist tmp;
660
661 sg_init_one(&tmp, buf, len);
662 crypto_digest_update(tcp_conn->data_rx_tfm, &tmp, 1);
663 }
664
665 static int iscsi_scsi_data_in(struct iscsi_conn *conn)
666 {
667 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
668 struct iscsi_cmd_task *ctask = tcp_conn->in.ctask;
669 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
670 struct scsi_cmnd *sc = ctask->sc;
671 struct scatterlist *sg;
672 int i, offset, rc = 0;
673
674 BUG_ON((void*)ctask != sc->SCp.ptr);
675
676 /*
677 * copying Data-In into the Scsi_Cmnd
678 */
679 if (!sc->use_sg) {
680 i = ctask->data_count;
681 rc = iscsi_ctask_copy(tcp_conn, ctask, sc->request_buffer,
682 sc->request_bufflen,
683 tcp_ctask->data_offset);
684 if (rc == -EAGAIN)
685 return rc;
686 if (conn->datadgst_en)
687 iscsi_recv_digest_update(tcp_conn, sc->request_buffer,
688 i);
689 rc = 0;
690 goto done;
691 }
692
693 offset = tcp_ctask->data_offset;
694 sg = sc->request_buffer;
695
696 if (tcp_ctask->data_offset)
697 for (i = 0; i < tcp_ctask->sg_count; i++)
698 offset -= sg[i].length;
699 /* we've passed through partial sg*/
700 if (offset < 0)
701 offset = 0;
702
703 for (i = tcp_ctask->sg_count; i < sc->use_sg; i++) {
704 char *dest;
705
706 dest = kmap_atomic(sg[i].page, KM_SOFTIRQ0);
707 rc = iscsi_ctask_copy(tcp_conn, ctask, dest + sg[i].offset,
708 sg[i].length, offset);
709 kunmap_atomic(dest, KM_SOFTIRQ0);
710 if (rc == -EAGAIN)
711 /* continue with the next SKB/PDU */
712 return rc;
713 if (!rc) {
714 if (conn->datadgst_en) {
715 if (!offset)
716 crypto_digest_update(
717 tcp_conn->data_rx_tfm,
718 &sg[i], 1);
719 else
720 partial_sg_digest_update(tcp_conn,
721 &sg[i],
722 sg[i].offset + offset,
723 sg[i].length - offset);
724 }
725 offset = 0;
726 tcp_ctask->sg_count++;
727 }
728
729 if (!ctask->data_count) {
730 if (rc && conn->datadgst_en)
731 /*
732 * data-in is complete, but buffer not...
733 */
734 partial_sg_digest_update(tcp_conn, &sg[i],
735 sg[i].offset, sg[i].length-rc);
736 rc = 0;
737 break;
738 }
739
740 if (!tcp_conn->in.copy)
741 return -EAGAIN;
742 }
743 BUG_ON(ctask->data_count);
744
745 done:
746 /* check for non-exceptional status */
747 if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
748 debug_scsi("done [sc %lx res %d itt 0x%x]\n",
749 (long)sc, sc->result, ctask->itt);
750 spin_lock(&conn->session->lock);
751 __iscsi_ctask_cleanup(conn, ctask);
752 __iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
753 spin_unlock(&conn->session->lock);
754 }
755
756 return rc;
757 }
758
759 static int
760 iscsi_data_recv(struct iscsi_conn *conn)
761 {
762 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
763 int rc = 0, opcode;
764
765 opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
766 switch (opcode) {
767 case ISCSI_OP_SCSI_DATA_IN:
768 rc = iscsi_scsi_data_in(conn);
769 break;
770 case ISCSI_OP_SCSI_CMD_RSP:
771 spin_lock(&conn->session->lock);
772 __iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
773 spin_unlock(&conn->session->lock);
774 case ISCSI_OP_TEXT_RSP:
775 case ISCSI_OP_LOGIN_RSP:
776 case ISCSI_OP_NOOP_IN:
777 case ISCSI_OP_ASYNC_EVENT:
778 case ISCSI_OP_REJECT:
779 /*
780 * Collect data segment to the connection's data
781 * placeholder
782 */
783 if (iscsi_tcp_copy(tcp_conn)) {
784 rc = -EAGAIN;
785 goto exit;
786 }
787
788 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, tcp_conn->data,
789 tcp_conn->in.datalen);
790 if (!rc && conn->datadgst_en && opcode != ISCSI_OP_LOGIN_RSP)
791 iscsi_recv_digest_update(tcp_conn, tcp_conn->data,
792 tcp_conn->in.datalen);
793 break;
794 default:
795 BUG_ON(1);
796 }
797 exit:
798 return rc;
799 }
800
801 /**
802 * iscsi_tcp_data_recv - TCP receive in sendfile fashion
803 * @rd_desc: read descriptor
804 * @skb: socket buffer
805 * @offset: offset in skb
806 * @len: skb->len - offset
807 **/
808 static int
809 iscsi_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
810 unsigned int offset, size_t len)
811 {
812 int rc;
813 struct iscsi_conn *conn = rd_desc->arg.data;
814 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
815 int processed;
816 char pad[ISCSI_PAD_LEN];
817 struct scatterlist sg;
818
819 /*
820 * Save current SKB and its offset in the corresponding
821 * connection context.
822 */
823 tcp_conn->in.copy = skb->len - offset;
824 tcp_conn->in.offset = offset;
825 tcp_conn->in.skb = skb;
826 tcp_conn->in.len = tcp_conn->in.copy;
827 BUG_ON(tcp_conn->in.copy <= 0);
828 debug_tcp("in %d bytes\n", tcp_conn->in.copy);
829
830 more:
831 tcp_conn->in.copied = 0;
832 rc = 0;
833
834 if (unlikely(conn->suspend_rx)) {
835 debug_tcp("conn %d Rx suspended!\n", conn->id);
836 return 0;
837 }
838
839 if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER ||
840 tcp_conn->in_progress == IN_PROGRESS_HEADER_GATHER) {
841 rc = iscsi_hdr_extract(tcp_conn);
842 if (rc) {
843 if (rc == -EAGAIN)
844 goto nomore;
845 else {
846 iscsi_conn_failure(conn, rc);
847 return 0;
848 }
849 }
850
851 /*
852 * Verify and process incoming PDU header.
853 */
854 rc = iscsi_tcp_hdr_recv(conn);
855 if (!rc && tcp_conn->in.datalen) {
856 if (conn->datadgst_en) {
857 BUG_ON(!tcp_conn->data_rx_tfm);
858 crypto_digest_init(tcp_conn->data_rx_tfm);
859 }
860 tcp_conn->in_progress = IN_PROGRESS_DATA_RECV;
861 } else if (rc) {
862 iscsi_conn_failure(conn, rc);
863 return 0;
864 }
865 }
866
867 if (tcp_conn->in_progress == IN_PROGRESS_DDIGEST_RECV) {
868 uint32_t recv_digest;
869
870 debug_tcp("extra data_recv offset %d copy %d\n",
871 tcp_conn->in.offset, tcp_conn->in.copy);
872 skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
873 &recv_digest, 4);
874 tcp_conn->in.offset += 4;
875 tcp_conn->in.copy -= 4;
876 if (recv_digest != tcp_conn->in.datadgst) {
877 debug_tcp("iscsi_tcp: data digest error!"
878 "0x%x != 0x%x\n", recv_digest,
879 tcp_conn->in.datadgst);
880 iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
881 return 0;
882 } else {
883 debug_tcp("iscsi_tcp: data digest match!"
884 "0x%x == 0x%x\n", recv_digest,
885 tcp_conn->in.datadgst);
886 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
887 }
888 }
889
890 if (tcp_conn->in_progress == IN_PROGRESS_DATA_RECV &&
891 tcp_conn->in.copy) {
892
893 debug_tcp("data_recv offset %d copy %d\n",
894 tcp_conn->in.offset, tcp_conn->in.copy);
895
896 rc = iscsi_data_recv(conn);
897 if (rc) {
898 if (rc == -EAGAIN)
899 goto again;
900 iscsi_conn_failure(conn, rc);
901 return 0;
902 }
903 tcp_conn->in.copy -= tcp_conn->in.padding;
904 tcp_conn->in.offset += tcp_conn->in.padding;
905 if (conn->datadgst_en) {
906 if (tcp_conn->in.padding) {
907 debug_tcp("padding -> %d\n",
908 tcp_conn->in.padding);
909 memset(pad, 0, tcp_conn->in.padding);
910 sg_init_one(&sg, pad, tcp_conn->in.padding);
911 crypto_digest_update(tcp_conn->data_rx_tfm,
912 &sg, 1);
913 }
914 crypto_digest_final(tcp_conn->data_rx_tfm,
915 (u8 *) & tcp_conn->in.datadgst);
916 debug_tcp("rx digest 0x%x\n", tcp_conn->in.datadgst);
917 tcp_conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
918 } else
919 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
920 }
921
922 debug_tcp("f, processed %d from out of %d padding %d\n",
923 tcp_conn->in.offset - offset, (int)len, tcp_conn->in.padding);
924 BUG_ON(tcp_conn->in.offset - offset > len);
925
926 if (tcp_conn->in.offset - offset != len) {
927 debug_tcp("continue to process %d bytes\n",
928 (int)len - (tcp_conn->in.offset - offset));
929 goto more;
930 }
931
932 nomore:
933 processed = tcp_conn->in.offset - offset;
934 BUG_ON(processed == 0);
935 return processed;
936
937 again:
938 processed = tcp_conn->in.offset - offset;
939 debug_tcp("c, processed %d from out of %d rd_desc_cnt %d\n",
940 processed, (int)len, (int)rd_desc->count);
941 BUG_ON(processed == 0);
942 BUG_ON(processed > len);
943
944 conn->rxdata_octets += processed;
945 return processed;
946 }
947
948 static void
949 iscsi_tcp_data_ready(struct sock *sk, int flag)
950 {
951 struct iscsi_conn *conn = sk->sk_user_data;
952 read_descriptor_t rd_desc;
953
954 read_lock(&sk->sk_callback_lock);
955
956 /*
957 * Use rd_desc to pass 'conn' to iscsi_tcp_data_recv.
958 * We set count to 1 because we want the network layer to
959 * hand us all the skbs that are available. iscsi_tcp_data_recv
960 * handled pdus that cross buffers or pdus that still need data.
961 */
962 rd_desc.arg.data = conn;
963 rd_desc.count = 1;
964 tcp_read_sock(sk, &rd_desc, iscsi_tcp_data_recv);
965
966 read_unlock(&sk->sk_callback_lock);
967 }
968
969 static void
970 iscsi_tcp_state_change(struct sock *sk)
971 {
972 struct iscsi_tcp_conn *tcp_conn;
973 struct iscsi_conn *conn;
974 struct iscsi_session *session;
975 void (*old_state_change)(struct sock *);
976
977 read_lock(&sk->sk_callback_lock);
978
979 conn = (struct iscsi_conn*)sk->sk_user_data;
980 session = conn->session;
981
982 if ((sk->sk_state == TCP_CLOSE_WAIT ||
983 sk->sk_state == TCP_CLOSE) &&
984 !atomic_read(&sk->sk_rmem_alloc)) {
985 debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
986 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
987 }
988
989 tcp_conn = conn->dd_data;
990 old_state_change = tcp_conn->old_state_change;
991
992 read_unlock(&sk->sk_callback_lock);
993
994 old_state_change(sk);
995 }
996
997 /**
998 * iscsi_write_space - Called when more output buffer space is available
999 * @sk: socket space is available for
1000 **/
1001 static void
1002 iscsi_write_space(struct sock *sk)
1003 {
1004 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
1005 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1006
1007 tcp_conn->old_write_space(sk);
1008 debug_tcp("iscsi_write_space: cid %d\n", conn->id);
1009 scsi_queue_work(conn->session->host, &conn->xmitwork);
1010 }
1011
1012 static void
1013 iscsi_conn_set_callbacks(struct iscsi_conn *conn)
1014 {
1015 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1016 struct sock *sk = tcp_conn->sock->sk;
1017
1018 /* assign new callbacks */
1019 write_lock_bh(&sk->sk_callback_lock);
1020 sk->sk_user_data = conn;
1021 tcp_conn->old_data_ready = sk->sk_data_ready;
1022 tcp_conn->old_state_change = sk->sk_state_change;
1023 tcp_conn->old_write_space = sk->sk_write_space;
1024 sk->sk_data_ready = iscsi_tcp_data_ready;
1025 sk->sk_state_change = iscsi_tcp_state_change;
1026 sk->sk_write_space = iscsi_write_space;
1027 write_unlock_bh(&sk->sk_callback_lock);
1028 }
1029
1030 static void
1031 iscsi_conn_restore_callbacks(struct iscsi_conn *conn)
1032 {
1033 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1034 struct sock *sk = tcp_conn->sock->sk;
1035
1036 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
1037 write_lock_bh(&sk->sk_callback_lock);
1038 sk->sk_user_data = NULL;
1039 sk->sk_data_ready = tcp_conn->old_data_ready;
1040 sk->sk_state_change = tcp_conn->old_state_change;
1041 sk->sk_write_space = tcp_conn->old_write_space;
1042 sk->sk_no_check = 0;
1043 write_unlock_bh(&sk->sk_callback_lock);
1044 }
1045
1046 /**
1047 * iscsi_send - generic send routine
1048 * @sk: kernel's socket
1049 * @buf: buffer to write from
1050 * @size: actual size to write
1051 * @flags: socket's flags
1052 */
1053 static inline int
1054 iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
1055 {
1056 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1057 struct socket *sk = tcp_conn->sock;
1058 int offset = buf->sg.offset + buf->sent, res;
1059
1060 /*
1061 * if we got use_sg=0 or are sending something we kmallocd
1062 * then we did not have to do kmap (kmap returns page_address)
1063 *
1064 * if we got use_sg > 0, but had to drop down, we do not
1065 * set clustering so this should only happen for that
1066 * slab case.
1067 */
1068 if (buf->use_sendmsg)
1069 res = sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
1070 else
1071 res = tcp_conn->sendpage(sk, buf->sg.page, offset, size, flags);
1072
1073 if (res >= 0) {
1074 conn->txdata_octets += res;
1075 buf->sent += res;
1076 return res;
1077 }
1078
1079 tcp_conn->sendpage_failures_cnt++;
1080 if (res == -EAGAIN)
1081 res = -ENOBUFS;
1082 else
1083 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1084 return res;
1085 }
1086
1087 /**
1088 * iscsi_sendhdr - send PDU Header via tcp_sendpage()
1089 * @conn: iscsi connection
1090 * @buf: buffer to write from
1091 * @datalen: lenght of data to be sent after the header
1092 *
1093 * Notes:
1094 * (Tx, Fast Path)
1095 **/
1096 static inline int
1097 iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
1098 {
1099 int flags = 0; /* MSG_DONTWAIT; */
1100 int res, size;
1101
1102 size = buf->sg.length - buf->sent;
1103 BUG_ON(buf->sent + size > buf->sg.length);
1104 if (buf->sent + size != buf->sg.length || datalen)
1105 flags |= MSG_MORE;
1106
1107 res = iscsi_send(conn, buf, size, flags);
1108 debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
1109 if (res >= 0) {
1110 if (size != res)
1111 return -EAGAIN;
1112 return 0;
1113 }
1114
1115 return res;
1116 }
1117
1118 /**
1119 * iscsi_sendpage - send one page of iSCSI Data-Out.
1120 * @conn: iscsi connection
1121 * @buf: buffer to write from
1122 * @count: remaining data
1123 * @sent: number of bytes sent
1124 *
1125 * Notes:
1126 * (Tx, Fast Path)
1127 **/
1128 static inline int
1129 iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
1130 int *count, int *sent)
1131 {
1132 int flags = 0; /* MSG_DONTWAIT; */
1133 int res, size;
1134
1135 size = buf->sg.length - buf->sent;
1136 BUG_ON(buf->sent + size > buf->sg.length);
1137 if (size > *count)
1138 size = *count;
1139 if (buf->sent + size != buf->sg.length || *count != size)
1140 flags |= MSG_MORE;
1141
1142 res = iscsi_send(conn, buf, size, flags);
1143 debug_tcp("sendpage: %d bytes, sent %d left %d sent %d res %d\n",
1144 size, buf->sent, *count, *sent, res);
1145 if (res >= 0) {
1146 *count -= res;
1147 *sent += res;
1148 if (size != res)
1149 return -EAGAIN;
1150 return 0;
1151 }
1152
1153 return res;
1154 }
1155
1156 static inline void
1157 iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
1158 struct iscsi_cmd_task *ctask)
1159 {
1160 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1161
1162 BUG_ON(!tcp_conn->data_tx_tfm);
1163 crypto_digest_init(tcp_conn->data_tx_tfm);
1164 tcp_ctask->digest_count = 4;
1165 }
1166
1167 static int
1168 iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1169 struct iscsi_buf *buf, uint32_t *digest, int final)
1170 {
1171 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1172 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1173 int rc = 0;
1174 int sent = 0;
1175
1176 if (final)
1177 crypto_digest_final(tcp_conn->data_tx_tfm, (u8*)digest);
1178
1179 iscsi_buf_init_iov(buf, (char*)digest, 4);
1180 rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
1181 if (rc) {
1182 tcp_ctask->datadigest = *digest;
1183 tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
1184 } else
1185 tcp_ctask->digest_count = 4;
1186 return rc;
1187 }
1188
1189 /**
1190 * iscsi_solicit_data_cont - initialize next Data-Out
1191 * @conn: iscsi connection
1192 * @ctask: scsi command task
1193 * @r2t: R2T info
1194 * @left: bytes left to transfer
1195 *
1196 * Notes:
1197 * Initialize next Data-Out within this R2T sequence and continue
1198 * to process next Scatter-Gather element(if any) of this SCSI command.
1199 *
1200 * Called under connection lock.
1201 **/
1202 static void
1203 iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1204 struct iscsi_r2t_info *r2t, int left)
1205 {
1206 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1207 struct iscsi_data *hdr;
1208 struct scsi_cmnd *sc = ctask->sc;
1209 int new_offset;
1210
1211 hdr = &r2t->dtask.hdr;
1212 memset(hdr, 0, sizeof(struct iscsi_data));
1213 hdr->ttt = r2t->ttt;
1214 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
1215 r2t->solicit_datasn++;
1216 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
1217 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1218 hdr->itt = ctask->hdr->itt;
1219 hdr->exp_statsn = r2t->exp_statsn;
1220 new_offset = r2t->data_offset + r2t->sent;
1221 hdr->offset = cpu_to_be32(new_offset);
1222 if (left > conn->max_xmit_dlength) {
1223 hton24(hdr->dlength, conn->max_xmit_dlength);
1224 r2t->data_count = conn->max_xmit_dlength;
1225 } else {
1226 hton24(hdr->dlength, left);
1227 r2t->data_count = left;
1228 hdr->flags = ISCSI_FLAG_CMD_FINAL;
1229 }
1230 conn->dataout_pdus_cnt++;
1231
1232 iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
1233 sizeof(struct iscsi_hdr));
1234
1235 if (sc->use_sg && !iscsi_buf_left(&r2t->sendbuf)) {
1236 BUG_ON(tcp_ctask->bad_sg == r2t->sg);
1237 iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
1238 r2t->sg += 1;
1239 } else
1240 iscsi_buf_init_iov(&tcp_ctask->sendbuf,
1241 (char*)sc->request_buffer + new_offset,
1242 r2t->data_count);
1243 }
1244
1245 static void
1246 iscsi_unsolicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1247 {
1248 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1249 struct iscsi_data_task *dtask;
1250
1251 dtask = tcp_ctask->dtask = &tcp_ctask->unsol_dtask;
1252 iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr,
1253 tcp_ctask->r2t_data_count);
1254 iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
1255 sizeof(struct iscsi_hdr));
1256 }
1257
1258 /**
1259 * iscsi_tcp_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
1260 * @conn: iscsi connection
1261 * @ctask: scsi command task
1262 * @sc: scsi command
1263 **/
1264 static void
1265 iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
1266 {
1267 struct scsi_cmnd *sc = ctask->sc;
1268 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1269
1270 BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
1271
1272 tcp_ctask->sent = 0;
1273 tcp_ctask->sg_count = 0;
1274
1275 if (sc->sc_data_direction == DMA_TO_DEVICE) {
1276 tcp_ctask->xmstate = XMSTATE_W_HDR;
1277 tcp_ctask->exp_r2tsn = 0;
1278 BUG_ON(ctask->total_length == 0);
1279
1280 if (sc->use_sg) {
1281 struct scatterlist *sg = sc->request_buffer;
1282
1283 iscsi_buf_init_sg(&tcp_ctask->sendbuf,
1284 &sg[tcp_ctask->sg_count++]);
1285 tcp_ctask->sg = sg;
1286 tcp_ctask->bad_sg = sg + sc->use_sg;
1287 } else
1288 iscsi_buf_init_iov(&tcp_ctask->sendbuf,
1289 sc->request_buffer,
1290 sc->request_bufflen);
1291
1292 if (ctask->imm_count)
1293 tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
1294
1295 tcp_ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
1296 if (tcp_ctask->pad_count) {
1297 tcp_ctask->pad_count = ISCSI_PAD_LEN -
1298 tcp_ctask->pad_count;
1299 debug_scsi("write padding %d bytes\n",
1300 tcp_ctask->pad_count);
1301 tcp_ctask->xmstate |= XMSTATE_W_PAD;
1302 }
1303
1304 if (ctask->unsol_count)
1305 tcp_ctask->xmstate |= XMSTATE_UNS_HDR |
1306 XMSTATE_UNS_INIT;
1307 tcp_ctask->r2t_data_count = ctask->total_length -
1308 ctask->imm_count -
1309 ctask->unsol_count;
1310
1311 debug_scsi("cmd [itt %x total %d imm %d imm_data %d "
1312 "r2t_data %d]\n",
1313 ctask->itt, ctask->total_length, ctask->imm_count,
1314 ctask->unsol_count, tcp_ctask->r2t_data_count);
1315 } else
1316 tcp_ctask->xmstate = XMSTATE_R_HDR;
1317
1318 iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
1319 sizeof(struct iscsi_hdr));
1320 }
1321
1322 /**
1323 * iscsi_tcp_mtask_xmit - xmit management(immediate) task
1324 * @conn: iscsi connection
1325 * @mtask: task management task
1326 *
1327 * Notes:
1328 * The function can return -EAGAIN in which case caller must
1329 * call it again later, or recover. '0' return code means successful
1330 * xmit.
1331 *
1332 * Management xmit state machine consists of two states:
1333 * IN_PROGRESS_IMM_HEAD - PDU Header xmit in progress
1334 * IN_PROGRESS_IMM_DATA - PDU Data xmit in progress
1335 **/
1336 static int
1337 iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
1338 {
1339 struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
1340 int rc;
1341
1342 debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
1343 conn->id, tcp_mtask->xmstate, mtask->itt);
1344
1345 if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
1346 tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
1347 if (mtask->data_count)
1348 tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
1349 if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
1350 conn->stop_stage != STOP_CONN_RECOVER &&
1351 conn->hdrdgst_en)
1352 iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
1353 (u8*)tcp_mtask->hdrext);
1354 rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
1355 mtask->data_count);
1356 if (rc) {
1357 tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
1358 if (mtask->data_count)
1359 tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
1360 return rc;
1361 }
1362 }
1363
1364 if (tcp_mtask->xmstate & XMSTATE_IMM_DATA) {
1365 BUG_ON(!mtask->data_count);
1366 tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
1367 /* FIXME: implement.
1368 * Virtual buffer could be spreaded across multiple pages...
1369 */
1370 do {
1371 int rc;
1372
1373 rc = iscsi_sendpage(conn, &tcp_mtask->sendbuf,
1374 &mtask->data_count, &tcp_mtask->sent);
1375 if (rc) {
1376 tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
1377 return rc;
1378 }
1379 } while (mtask->data_count);
1380 }
1381
1382 BUG_ON(tcp_mtask->xmstate != XMSTATE_IDLE);
1383 if (mtask->hdr->itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1384 struct iscsi_session *session = conn->session;
1385
1386 spin_lock_bh(&session->lock);
1387 list_del(&conn->mtask->running);
1388 __kfifo_put(session->mgmtpool.queue, (void*)&conn->mtask,
1389 sizeof(void*));
1390 spin_unlock_bh(&session->lock);
1391 }
1392 return 0;
1393 }
1394
1395 static inline int
1396 handle_xmstate_r_hdr(struct iscsi_conn *conn,
1397 struct iscsi_tcp_cmd_task *tcp_ctask)
1398 {
1399 int rc;
1400
1401 tcp_ctask->xmstate &= ~XMSTATE_R_HDR;
1402 if (conn->hdrdgst_en)
1403 iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
1404 (u8*)tcp_ctask->hdrext);
1405 rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, 0);
1406 if (!rc) {
1407 BUG_ON(tcp_ctask->xmstate != XMSTATE_IDLE);
1408 return 0; /* wait for Data-In */
1409 }
1410 tcp_ctask->xmstate |= XMSTATE_R_HDR;
1411 return rc;
1412 }
1413
1414 static inline int
1415 handle_xmstate_w_hdr(struct iscsi_conn *conn,
1416 struct iscsi_cmd_task *ctask)
1417 {
1418 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1419 int rc;
1420
1421 tcp_ctask->xmstate &= ~XMSTATE_W_HDR;
1422 if (conn->hdrdgst_en)
1423 iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
1424 (u8*)tcp_ctask->hdrext);
1425 rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
1426 if (rc)
1427 tcp_ctask->xmstate |= XMSTATE_W_HDR;
1428 return rc;
1429 }
1430
1431 static inline int
1432 handle_xmstate_data_digest(struct iscsi_conn *conn,
1433 struct iscsi_cmd_task *ctask)
1434 {
1435 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1436 int rc;
1437
1438 tcp_ctask->xmstate &= ~XMSTATE_DATA_DIGEST;
1439 debug_tcp("resent data digest 0x%x\n", tcp_ctask->datadigest);
1440 rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
1441 &tcp_ctask->datadigest, 0);
1442 if (rc) {
1443 tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
1444 debug_tcp("resent data digest 0x%x fail!\n",
1445 tcp_ctask->datadigest);
1446 }
1447
1448 return rc;
1449 }
1450
1451 static inline int
1452 handle_xmstate_imm_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1453 {
1454 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1455 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1456 int rc;
1457
1458 BUG_ON(!ctask->imm_count);
1459 tcp_ctask->xmstate &= ~XMSTATE_IMM_DATA;
1460
1461 if (conn->datadgst_en) {
1462 iscsi_data_digest_init(tcp_conn, ctask);
1463 tcp_ctask->immdigest = 0;
1464 }
1465
1466 for (;;) {
1467 rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
1468 &ctask->imm_count, &tcp_ctask->sent);
1469 if (rc) {
1470 tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
1471 if (conn->datadgst_en) {
1472 crypto_digest_final(tcp_conn->data_tx_tfm,
1473 (u8*)&tcp_ctask->immdigest);
1474 debug_tcp("tx imm sendpage fail 0x%x\n",
1475 tcp_ctask->datadigest);
1476 }
1477 return rc;
1478 }
1479 if (conn->datadgst_en)
1480 crypto_digest_update(tcp_conn->data_tx_tfm,
1481 &tcp_ctask->sendbuf.sg, 1);
1482
1483 if (!ctask->imm_count)
1484 break;
1485 iscsi_buf_init_sg(&tcp_ctask->sendbuf,
1486 &tcp_ctask->sg[tcp_ctask->sg_count++]);
1487 }
1488
1489 if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
1490 rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
1491 &tcp_ctask->immdigest, 1);
1492 if (rc) {
1493 debug_tcp("sending imm digest 0x%x fail!\n",
1494 tcp_ctask->immdigest);
1495 return rc;
1496 }
1497 debug_tcp("sending imm digest 0x%x\n", tcp_ctask->immdigest);
1498 }
1499
1500 return 0;
1501 }
1502
1503 static inline int
1504 handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1505 {
1506 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1507 struct iscsi_data_task *dtask;
1508 int rc;
1509
1510 tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
1511 if (tcp_ctask->xmstate & XMSTATE_UNS_INIT) {
1512 iscsi_unsolicit_data_init(conn, ctask);
1513 dtask = tcp_ctask->dtask;
1514 if (conn->hdrdgst_en)
1515 iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
1516 (u8*)dtask->hdrext);
1517 tcp_ctask->xmstate &= ~XMSTATE_UNS_INIT;
1518 }
1519
1520 rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->data_count);
1521 if (rc) {
1522 tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
1523 tcp_ctask->xmstate |= XMSTATE_UNS_HDR;
1524 return rc;
1525 }
1526
1527 debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
1528 ctask->itt, ctask->unsol_count, tcp_ctask->sent);
1529 return 0;
1530 }
1531
1532 static inline int
1533 handle_xmstate_uns_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1534 {
1535 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1536 struct iscsi_data_task *dtask = tcp_ctask->dtask;
1537 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1538 int rc;
1539
1540 BUG_ON(!ctask->data_count);
1541 tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
1542
1543 if (conn->datadgst_en) {
1544 iscsi_data_digest_init(tcp_conn, ctask);
1545 dtask->digest = 0;
1546 }
1547
1548 for (;;) {
1549 int start = tcp_ctask->sent;
1550
1551 rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
1552 &ctask->data_count, &tcp_ctask->sent);
1553 if (rc) {
1554 ctask->unsol_count -= tcp_ctask->sent - start;
1555 tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
1556 /* will continue with this ctask later.. */
1557 if (conn->datadgst_en) {
1558 crypto_digest_final(tcp_conn->data_tx_tfm,
1559 (u8 *)&dtask->digest);
1560 debug_tcp("tx uns data fail 0x%x\n",
1561 dtask->digest);
1562 }
1563 return rc;
1564 }
1565
1566 BUG_ON(tcp_ctask->sent > ctask->total_length);
1567 ctask->unsol_count -= tcp_ctask->sent - start;
1568
1569 /*
1570 * XXX:we may run here with un-initial sendbuf.
1571 * so pass it
1572 */
1573 if (conn->datadgst_en && tcp_ctask->sent - start > 0)
1574 crypto_digest_update(tcp_conn->data_tx_tfm,
1575 &tcp_ctask->sendbuf.sg, 1);
1576
1577 if (!ctask->data_count)
1578 break;
1579 iscsi_buf_init_sg(&tcp_ctask->sendbuf,
1580 &tcp_ctask->sg[tcp_ctask->sg_count++]);
1581 }
1582 BUG_ON(ctask->unsol_count < 0);
1583
1584 /*
1585 * Done with the Data-Out. Next, check if we need
1586 * to send another unsolicited Data-Out.
1587 */
1588 if (ctask->unsol_count) {
1589 if (conn->datadgst_en) {
1590 rc = iscsi_digest_final_send(conn, ctask,
1591 &dtask->digestbuf,
1592 &dtask->digest, 1);
1593 if (rc) {
1594 debug_tcp("send uns digest 0x%x fail\n",
1595 dtask->digest);
1596 return rc;
1597 }
1598 debug_tcp("sending uns digest 0x%x, more uns\n",
1599 dtask->digest);
1600 }
1601 tcp_ctask->xmstate |= XMSTATE_UNS_INIT;
1602 return 1;
1603 }
1604
1605 if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
1606 rc = iscsi_digest_final_send(conn, ctask,
1607 &dtask->digestbuf,
1608 &dtask->digest, 1);
1609 if (rc) {
1610 debug_tcp("send last uns digest 0x%x fail\n",
1611 dtask->digest);
1612 return rc;
1613 }
1614 debug_tcp("sending uns digest 0x%x\n",dtask->digest);
1615 }
1616
1617 return 0;
1618 }
1619
1620 static inline int
1621 handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1622 {
1623 struct iscsi_session *session = conn->session;
1624 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1625 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1626 struct iscsi_r2t_info *r2t = tcp_ctask->r2t;
1627 struct iscsi_data_task *dtask = &r2t->dtask;
1628 int left, rc;
1629
1630 tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
1631 tcp_ctask->dtask = dtask;
1632
1633 if (conn->datadgst_en) {
1634 iscsi_data_digest_init(tcp_conn, ctask);
1635 dtask->digest = 0;
1636 }
1637 solicit_again:
1638 /*
1639 * send Data-Out whitnin this R2T sequence.
1640 */
1641 if (!r2t->data_count)
1642 goto data_out_done;
1643
1644 rc = iscsi_sendpage(conn, &r2t->sendbuf, &r2t->data_count, &r2t->sent);
1645 if (rc) {
1646 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1647 /* will continue with this ctask later.. */
1648 if (conn->datadgst_en) {
1649 crypto_digest_final(tcp_conn->data_tx_tfm,
1650 (u8 *)&dtask->digest);
1651 debug_tcp("r2t data send fail 0x%x\n", dtask->digest);
1652 }
1653 return rc;
1654 }
1655
1656 BUG_ON(r2t->data_count < 0);
1657 if (conn->datadgst_en)
1658 crypto_digest_update(tcp_conn->data_tx_tfm, &r2t->sendbuf.sg,
1659 1);
1660
1661 if (r2t->data_count) {
1662 BUG_ON(ctask->sc->use_sg == 0);
1663 if (!iscsi_buf_left(&r2t->sendbuf)) {
1664 BUG_ON(tcp_ctask->bad_sg == r2t->sg);
1665 iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
1666 r2t->sg += 1;
1667 }
1668 goto solicit_again;
1669 }
1670
1671 data_out_done:
1672 /*
1673 * Done with this Data-Out. Next, check if we have
1674 * to send another Data-Out for this R2T.
1675 */
1676 BUG_ON(r2t->data_length - r2t->sent < 0);
1677 left = r2t->data_length - r2t->sent;
1678 if (left) {
1679 if (conn->datadgst_en) {
1680 rc = iscsi_digest_final_send(conn, ctask,
1681 &dtask->digestbuf,
1682 &dtask->digest, 1);
1683 if (rc) {
1684 debug_tcp("send r2t data digest 0x%x"
1685 "fail\n", dtask->digest);
1686 return rc;
1687 }
1688 debug_tcp("r2t data send digest 0x%x\n",
1689 dtask->digest);
1690 }
1691 iscsi_solicit_data_cont(conn, ctask, r2t, left);
1692 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1693 tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1694 return 1;
1695 }
1696
1697 /*
1698 * Done with this R2T. Check if there are more
1699 * outstanding R2Ts ready to be processed.
1700 */
1701 BUG_ON(tcp_ctask->r2t_data_count - r2t->data_length < 0);
1702 if (conn->datadgst_en) {
1703 rc = iscsi_digest_final_send(conn, ctask, &dtask->digestbuf,
1704 &dtask->digest, 1);
1705 if (rc) {
1706 debug_tcp("send last r2t data digest 0x%x"
1707 "fail\n", dtask->digest);
1708 return rc;
1709 }
1710 debug_tcp("r2t done dout digest 0x%x\n", dtask->digest);
1711 }
1712
1713 tcp_ctask->r2t_data_count -= r2t->data_length;
1714 tcp_ctask->r2t = NULL;
1715 spin_lock_bh(&session->lock);
1716 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
1717 spin_unlock_bh(&session->lock);
1718 if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
1719 tcp_ctask->r2t = r2t;
1720 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1721 tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1722 return 1;
1723 }
1724
1725 return 0;
1726 }
1727
1728 static inline int
1729 handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1730 {
1731 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1732 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1733 struct iscsi_data_task *dtask = tcp_ctask->dtask;
1734 int sent, rc;
1735
1736 tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
1737 iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
1738 tcp_ctask->pad_count);
1739 rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
1740 &sent);
1741 if (rc) {
1742 tcp_ctask->xmstate |= XMSTATE_W_PAD;
1743 return rc;
1744 }
1745
1746 if (conn->datadgst_en) {
1747 crypto_digest_update(tcp_conn->data_tx_tfm,
1748 &tcp_ctask->sendbuf.sg, 1);
1749 /* imm data? */
1750 if (!dtask) {
1751 rc = iscsi_digest_final_send(conn, ctask,
1752 &tcp_ctask->immbuf,
1753 &tcp_ctask->immdigest, 1);
1754 if (rc) {
1755 debug_tcp("send padding digest 0x%x"
1756 "fail!\n", tcp_ctask->immdigest);
1757 return rc;
1758 }
1759 debug_tcp("done with padding, digest 0x%x\n",
1760 tcp_ctask->datadigest);
1761 } else {
1762 rc = iscsi_digest_final_send(conn, ctask,
1763 &dtask->digestbuf,
1764 &dtask->digest, 1);
1765 if (rc) {
1766 debug_tcp("send padding digest 0x%x"
1767 "fail\n", dtask->digest);
1768 return rc;
1769 }
1770 debug_tcp("done with padding, digest 0x%x\n",
1771 dtask->digest);
1772 }
1773 }
1774
1775 return 0;
1776 }
1777
1778 static int
1779 iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1780 {
1781 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1782 int rc = 0;
1783
1784 debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
1785 conn->id, tcp_ctask->xmstate, ctask->itt);
1786
1787 /*
1788 * serialize with TMF AbortTask
1789 */
1790 if (ctask->mtask)
1791 return rc;
1792
1793 if (tcp_ctask->xmstate & XMSTATE_R_HDR)
1794 return handle_xmstate_r_hdr(conn, tcp_ctask);
1795
1796 if (tcp_ctask->xmstate & XMSTATE_W_HDR) {
1797 rc = handle_xmstate_w_hdr(conn, ctask);
1798 if (rc)
1799 return rc;
1800 }
1801
1802 /* XXX: for data digest xmit recover */
1803 if (tcp_ctask->xmstate & XMSTATE_DATA_DIGEST) {
1804 rc = handle_xmstate_data_digest(conn, ctask);
1805 if (rc)
1806 return rc;
1807 }
1808
1809 if (tcp_ctask->xmstate & XMSTATE_IMM_DATA) {
1810 rc = handle_xmstate_imm_data(conn, ctask);
1811 if (rc)
1812 return rc;
1813 }
1814
1815 if (tcp_ctask->xmstate & XMSTATE_UNS_HDR) {
1816 BUG_ON(!ctask->unsol_count);
1817 tcp_ctask->xmstate &= ~XMSTATE_UNS_HDR;
1818 unsolicit_head_again:
1819 rc = handle_xmstate_uns_hdr(conn, ctask);
1820 if (rc)
1821 return rc;
1822 }
1823
1824 if (tcp_ctask->xmstate & XMSTATE_UNS_DATA) {
1825 rc = handle_xmstate_uns_data(conn, ctask);
1826 if (rc == 1)
1827 goto unsolicit_head_again;
1828 else if (rc)
1829 return rc;
1830 goto done;
1831 }
1832
1833 if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
1834 struct iscsi_r2t_info *r2t;
1835
1836 tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1837 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1838 if (!tcp_ctask->r2t)
1839 __kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
1840 sizeof(void*));
1841 solicit_head_again:
1842 r2t = tcp_ctask->r2t;
1843 if (conn->hdrdgst_en)
1844 iscsi_hdr_digest(conn, &r2t->headbuf,
1845 (u8*)r2t->dtask.hdrext);
1846 rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
1847 if (rc) {
1848 tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
1849 tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
1850 return rc;
1851 }
1852
1853 debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
1854 r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
1855 r2t->sent);
1856 }
1857
1858 if (tcp_ctask->xmstate & XMSTATE_SOL_DATA) {
1859 rc = handle_xmstate_sol_data(conn, ctask);
1860 if (rc == 1)
1861 goto solicit_head_again;
1862 if (rc)
1863 return rc;
1864 }
1865
1866 done:
1867 /*
1868 * Last thing to check is whether we need to send write
1869 * padding. Note that we check for xmstate equality, not just the bit.
1870 */
1871 if (tcp_ctask->xmstate == XMSTATE_W_PAD)
1872 rc = handle_xmstate_w_pad(conn, ctask);
1873
1874 return rc;
1875 }
1876
1877 static struct iscsi_cls_conn *
1878 iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1879 {
1880 struct iscsi_conn *conn;
1881 struct iscsi_cls_conn *cls_conn;
1882 struct iscsi_tcp_conn *tcp_conn;
1883
1884 cls_conn = iscsi_conn_setup(cls_session, conn_idx);
1885 if (!cls_conn)
1886 return NULL;
1887 conn = cls_conn->dd_data;
1888 /*
1889 * due to strange issues with iser these are not set
1890 * in iscsi_conn_setup
1891 */
1892 conn->max_recv_dlength = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
1893
1894 tcp_conn = kzalloc(sizeof(*tcp_conn), GFP_KERNEL);
1895 if (!tcp_conn)
1896 goto tcp_conn_alloc_fail;
1897
1898 conn->dd_data = tcp_conn;
1899 tcp_conn->iscsi_conn = conn;
1900 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
1901 /* initial operational parameters */
1902 tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
1903 tcp_conn->data_size = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
1904
1905 /* allocate initial PDU receive place holder */
1906 if (tcp_conn->data_size <= PAGE_SIZE)
1907 tcp_conn->data = kmalloc(tcp_conn->data_size, GFP_KERNEL);
1908 else
1909 tcp_conn->data = (void*)__get_free_pages(GFP_KERNEL,
1910 get_order(tcp_conn->data_size));
1911 if (!tcp_conn->data)
1912 goto max_recv_dlenght_alloc_fail;
1913
1914 return cls_conn;
1915
1916 max_recv_dlenght_alloc_fail:
1917 kfree(tcp_conn);
1918 tcp_conn_alloc_fail:
1919 iscsi_conn_teardown(cls_conn);
1920 return NULL;
1921 }
1922
1923 static void
1924 iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
1925 {
1926 struct iscsi_conn *conn = cls_conn->dd_data;
1927 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1928 int digest = 0;
1929
1930 if (conn->hdrdgst_en || conn->datadgst_en)
1931 digest = 1;
1932
1933 iscsi_conn_teardown(cls_conn);
1934
1935 /* now free tcp_conn */
1936 if (digest) {
1937 if (tcp_conn->tx_tfm)
1938 crypto_free_tfm(tcp_conn->tx_tfm);
1939 if (tcp_conn->rx_tfm)
1940 crypto_free_tfm(tcp_conn->rx_tfm);
1941 if (tcp_conn->data_tx_tfm)
1942 crypto_free_tfm(tcp_conn->data_tx_tfm);
1943 if (tcp_conn->data_rx_tfm)
1944 crypto_free_tfm(tcp_conn->data_rx_tfm);
1945 }
1946
1947 /* free conn->data, size = MaxRecvDataSegmentLength */
1948 if (tcp_conn->data_size <= PAGE_SIZE)
1949 kfree(tcp_conn->data);
1950 else
1951 free_pages((unsigned long)tcp_conn->data,
1952 get_order(tcp_conn->data_size));
1953 kfree(tcp_conn);
1954 }
1955
1956 static int
1957 iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
1958 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
1959 int is_leading)
1960 {
1961 struct iscsi_conn *conn = cls_conn->dd_data;
1962 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1963 struct sock *sk;
1964 struct socket *sock;
1965 int err;
1966
1967 /* lookup for existing socket */
1968 sock = sockfd_lookup((int)transport_eph, &err);
1969 if (!sock) {
1970 printk(KERN_ERR "iscsi_tcp: sockfd_lookup failed %d\n", err);
1971 return -EEXIST;
1972 }
1973
1974 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
1975 if (err)
1976 return err;
1977
1978 /* bind iSCSI connection and socket */
1979 tcp_conn->sock = sock;
1980
1981 /* setup Socket parameters */
1982 sk = sock->sk;
1983 sk->sk_reuse = 1;
1984 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
1985 sk->sk_allocation = GFP_ATOMIC;
1986
1987 /* FIXME: disable Nagle's algorithm */
1988
1989 /*
1990 * Intercept TCP callbacks for sendfile like receive
1991 * processing.
1992 */
1993 conn->recv_lock = &sk->sk_callback_lock;
1994 iscsi_conn_set_callbacks(conn);
1995 tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
1996 /*
1997 * set receive state machine into initial state
1998 */
1999 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
2000
2001 return 0;
2002 }
2003
2004 static void
2005 iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
2006 {
2007 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2008 struct iscsi_r2t_info *r2t;
2009
2010 /* flush ctask's r2t queues */
2011 while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*)))
2012 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
2013 sizeof(void*));
2014
2015 __iscsi_ctask_cleanup(conn, ctask);
2016 }
2017
2018 static void
2019 iscsi_tcp_suspend_conn_rx(struct iscsi_conn *conn)
2020 {
2021 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2022 struct sock *sk;
2023
2024 if (!tcp_conn->sock)
2025 return;
2026
2027 sk = tcp_conn->sock->sk;
2028 write_lock_bh(&sk->sk_callback_lock);
2029 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2030 write_unlock_bh(&sk->sk_callback_lock);
2031 }
2032
2033 static void
2034 iscsi_tcp_terminate_conn(struct iscsi_conn *conn)
2035 {
2036 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2037
2038 if (!tcp_conn->sock)
2039 return;
2040
2041 sock_hold(tcp_conn->sock->sk);
2042 iscsi_conn_restore_callbacks(conn);
2043 sock_put(tcp_conn->sock->sk);
2044
2045 sock_release(tcp_conn->sock);
2046 tcp_conn->sock = NULL;
2047 conn->recv_lock = NULL;
2048 }
2049
2050 /* called with host lock */
2051 static void
2052 iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask,
2053 char *data, uint32_t data_size)
2054 {
2055 struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
2056
2057 iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
2058 sizeof(struct iscsi_hdr));
2059 tcp_mtask->xmstate = XMSTATE_IMM_HDR;
2060
2061 if (mtask->data_count)
2062 iscsi_buf_init_iov(&tcp_mtask->sendbuf, (char*)mtask->data,
2063 mtask->data_count);
2064 }
2065
2066 static int
2067 iscsi_r2tpool_alloc(struct iscsi_session *session)
2068 {
2069 int i;
2070 int cmd_i;
2071
2072 /*
2073 * initialize per-task: R2T pool and xmit queue
2074 */
2075 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2076 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
2077 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2078
2079 /*
2080 * pre-allocated x4 as much r2ts to handle race when
2081 * target acks DataOut faster than we data_xmit() queues
2082 * could replenish r2tqueue.
2083 */
2084
2085 /* R2T pool */
2086 if (iscsi_pool_init(&tcp_ctask->r2tpool, session->max_r2t * 4,
2087 (void***)&tcp_ctask->r2ts,
2088 sizeof(struct iscsi_r2t_info))) {
2089 goto r2t_alloc_fail;
2090 }
2091
2092 /* R2T xmit queue */
2093 tcp_ctask->r2tqueue = kfifo_alloc(
2094 session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
2095 if (tcp_ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
2096 iscsi_pool_free(&tcp_ctask->r2tpool,
2097 (void**)tcp_ctask->r2ts);
2098 goto r2t_alloc_fail;
2099 }
2100 }
2101
2102 return 0;
2103
2104 r2t_alloc_fail:
2105 for (i = 0; i < cmd_i; i++) {
2106 struct iscsi_cmd_task *ctask = session->cmds[i];
2107 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2108
2109 kfifo_free(tcp_ctask->r2tqueue);
2110 iscsi_pool_free(&tcp_ctask->r2tpool,
2111 (void**)tcp_ctask->r2ts);
2112 }
2113 return -ENOMEM;
2114 }
2115
2116 static void
2117 iscsi_r2tpool_free(struct iscsi_session *session)
2118 {
2119 int i;
2120
2121 for (i = 0; i < session->cmds_max; i++) {
2122 struct iscsi_cmd_task *ctask = session->cmds[i];
2123 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2124
2125 kfifo_free(tcp_ctask->r2tqueue);
2126 iscsi_pool_free(&tcp_ctask->r2tpool,
2127 (void**)tcp_ctask->r2ts);
2128 }
2129 }
2130
2131 static int
2132 iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
2133 char *buf, int buflen)
2134 {
2135 struct iscsi_conn *conn = cls_conn->dd_data;
2136 struct iscsi_session *session = conn->session;
2137 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2138 int value;
2139
2140 switch(param) {
2141 case ISCSI_PARAM_MAX_RECV_DLENGTH: {
2142 char *saveptr = tcp_conn->data;
2143 gfp_t flags = GFP_KERNEL;
2144
2145 sscanf(buf, "%d", &value);
2146 if (tcp_conn->data_size >= value) {
2147 iscsi_set_param(cls_conn, param, buf, buflen);
2148 break;
2149 }
2150
2151 spin_lock_bh(&session->lock);
2152 if (conn->stop_stage == STOP_CONN_RECOVER)
2153 flags = GFP_ATOMIC;
2154 spin_unlock_bh(&session->lock);
2155
2156 if (value <= PAGE_SIZE)
2157 tcp_conn->data = kmalloc(value, flags);
2158 else
2159 tcp_conn->data = (void*)__get_free_pages(flags,
2160 get_order(value));
2161 if (tcp_conn->data == NULL) {
2162 tcp_conn->data = saveptr;
2163 return -ENOMEM;
2164 }
2165 if (tcp_conn->data_size <= PAGE_SIZE)
2166 kfree(saveptr);
2167 else
2168 free_pages((unsigned long)saveptr,
2169 get_order(tcp_conn->data_size));
2170 iscsi_set_param(cls_conn, param, buf, buflen);
2171 tcp_conn->data_size = value;
2172 break;
2173 }
2174 case ISCSI_PARAM_HDRDGST_EN:
2175 iscsi_set_param(cls_conn, param, buf, buflen);
2176 tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
2177 if (conn->hdrdgst_en) {
2178 tcp_conn->hdr_size += sizeof(__u32);
2179 if (!tcp_conn->tx_tfm)
2180 tcp_conn->tx_tfm = crypto_alloc_tfm("crc32c",
2181 0);
2182 if (!tcp_conn->tx_tfm)
2183 return -ENOMEM;
2184 if (!tcp_conn->rx_tfm)
2185 tcp_conn->rx_tfm = crypto_alloc_tfm("crc32c",
2186 0);
2187 if (!tcp_conn->rx_tfm) {
2188 crypto_free_tfm(tcp_conn->tx_tfm);
2189 return -ENOMEM;
2190 }
2191 } else {
2192 if (tcp_conn->tx_tfm)
2193 crypto_free_tfm(tcp_conn->tx_tfm);
2194 if (tcp_conn->rx_tfm)
2195 crypto_free_tfm(tcp_conn->rx_tfm);
2196 }
2197 break;
2198 case ISCSI_PARAM_DATADGST_EN:
2199 iscsi_set_param(cls_conn, param, buf, buflen);
2200 if (conn->datadgst_en) {
2201 if (!tcp_conn->data_tx_tfm)
2202 tcp_conn->data_tx_tfm =
2203 crypto_alloc_tfm("crc32c", 0);
2204 if (!tcp_conn->data_tx_tfm)
2205 return -ENOMEM;
2206 if (!tcp_conn->data_rx_tfm)
2207 tcp_conn->data_rx_tfm =
2208 crypto_alloc_tfm("crc32c", 0);
2209 if (!tcp_conn->data_rx_tfm) {
2210 crypto_free_tfm(tcp_conn->data_tx_tfm);
2211 return -ENOMEM;
2212 }
2213 } else {
2214 if (tcp_conn->data_tx_tfm)
2215 crypto_free_tfm(tcp_conn->data_tx_tfm);
2216 if (tcp_conn->data_rx_tfm)
2217 crypto_free_tfm(tcp_conn->data_rx_tfm);
2218 }
2219 tcp_conn->sendpage = conn->datadgst_en ?
2220 sock_no_sendpage : tcp_conn->sock->ops->sendpage;
2221 break;
2222 case ISCSI_PARAM_MAX_R2T:
2223 sscanf(buf, "%d", &value);
2224 if (session->max_r2t == roundup_pow_of_two(value))
2225 break;
2226 iscsi_r2tpool_free(session);
2227 iscsi_set_param(cls_conn, param, buf, buflen);
2228 if (session->max_r2t & (session->max_r2t - 1))
2229 session->max_r2t = roundup_pow_of_two(session->max_r2t);
2230 if (iscsi_r2tpool_alloc(session))
2231 return -ENOMEM;
2232 break;
2233 default:
2234 return iscsi_set_param(cls_conn, param, buf, buflen);
2235 }
2236
2237 return 0;
2238 }
2239
2240 static int
2241 iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
2242 enum iscsi_param param, char *buf)
2243 {
2244 struct iscsi_conn *conn = cls_conn->dd_data;
2245 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2246 struct inet_sock *inet;
2247 struct ipv6_pinfo *np;
2248 struct sock *sk;
2249 int len;
2250
2251 switch(param) {
2252 case ISCSI_PARAM_CONN_PORT:
2253 mutex_lock(&conn->xmitmutex);
2254 if (!tcp_conn->sock) {
2255 mutex_unlock(&conn->xmitmutex);
2256 return -EINVAL;
2257 }
2258
2259 inet = inet_sk(tcp_conn->sock->sk);
2260 len = sprintf(buf, "%hu\n", be16_to_cpu(inet->dport));
2261 mutex_unlock(&conn->xmitmutex);
2262 break;
2263 case ISCSI_PARAM_CONN_ADDRESS:
2264 mutex_lock(&conn->xmitmutex);
2265 if (!tcp_conn->sock) {
2266 mutex_unlock(&conn->xmitmutex);
2267 return -EINVAL;
2268 }
2269
2270 sk = tcp_conn->sock->sk;
2271 if (sk->sk_family == PF_INET) {
2272 inet = inet_sk(sk);
2273 len = sprintf(buf, "%u.%u.%u.%u\n",
2274 NIPQUAD(inet->daddr));
2275 } else {
2276 np = inet6_sk(sk);
2277 len = sprintf(buf,
2278 "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
2279 NIP6(np->daddr));
2280 }
2281 mutex_unlock(&conn->xmitmutex);
2282 break;
2283 default:
2284 return iscsi_conn_get_param(cls_conn, param, buf);
2285 }
2286
2287 return len;
2288 }
2289
2290 static void
2291 iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
2292 {
2293 struct iscsi_conn *conn = cls_conn->dd_data;
2294 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2295
2296 stats->txdata_octets = conn->txdata_octets;
2297 stats->rxdata_octets = conn->rxdata_octets;
2298 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
2299 stats->dataout_pdus = conn->dataout_pdus_cnt;
2300 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
2301 stats->datain_pdus = conn->datain_pdus_cnt;
2302 stats->r2t_pdus = conn->r2t_pdus_cnt;
2303 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
2304 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
2305 stats->custom_length = 3;
2306 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
2307 stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
2308 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
2309 stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
2310 strcpy(stats->custom[2].desc, "eh_abort_cnt");
2311 stats->custom[2].value = conn->eh_abort_cnt;
2312 }
2313
2314 static struct iscsi_cls_session *
2315 iscsi_tcp_session_create(struct iscsi_transport *iscsit,
2316 struct scsi_transport_template *scsit,
2317 uint32_t initial_cmdsn, uint32_t *hostno)
2318 {
2319 struct iscsi_cls_session *cls_session;
2320 struct iscsi_session *session;
2321 uint32_t hn;
2322 int cmd_i;
2323
2324 cls_session = iscsi_session_setup(iscsit, scsit,
2325 sizeof(struct iscsi_tcp_cmd_task),
2326 sizeof(struct iscsi_tcp_mgmt_task),
2327 initial_cmdsn, &hn);
2328 if (!cls_session)
2329 return NULL;
2330 *hostno = hn;
2331
2332 session = class_to_transport_session(cls_session);
2333 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2334 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
2335 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2336
2337 ctask->hdr = &tcp_ctask->hdr;
2338 }
2339
2340 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
2341 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
2342 struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
2343
2344 mtask->hdr = &tcp_mtask->hdr;
2345 }
2346
2347 if (iscsi_r2tpool_alloc(class_to_transport_session(cls_session)))
2348 goto r2tpool_alloc_fail;
2349
2350 return cls_session;
2351
2352 r2tpool_alloc_fail:
2353 iscsi_session_teardown(cls_session);
2354 return NULL;
2355 }
2356
2357 static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
2358 {
2359 iscsi_r2tpool_free(class_to_transport_session(cls_session));
2360 iscsi_session_teardown(cls_session);
2361 }
2362
2363 static struct scsi_host_template iscsi_sht = {
2364 .name = "iSCSI Initiator over TCP/IP, v"
2365 ISCSI_TCP_VERSION,
2366 .queuecommand = iscsi_queuecommand,
2367 .change_queue_depth = iscsi_change_queue_depth,
2368 .can_queue = ISCSI_XMIT_CMDS_MAX - 1,
2369 .sg_tablesize = ISCSI_SG_TABLESIZE,
2370 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
2371 .eh_abort_handler = iscsi_eh_abort,
2372 .eh_host_reset_handler = iscsi_eh_host_reset,
2373 .use_clustering = DISABLE_CLUSTERING,
2374 .proc_name = "iscsi_tcp",
2375 .this_id = -1,
2376 };
2377
2378 static struct iscsi_transport iscsi_tcp_transport = {
2379 .owner = THIS_MODULE,
2380 .name = "tcp",
2381 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
2382 | CAP_DATADGST,
2383 .param_mask = ISCSI_MAX_RECV_DLENGTH |
2384 ISCSI_MAX_XMIT_DLENGTH |
2385 ISCSI_HDRDGST_EN |
2386 ISCSI_DATADGST_EN |
2387 ISCSI_INITIAL_R2T_EN |
2388 ISCSI_MAX_R2T |
2389 ISCSI_IMM_DATA_EN |
2390 ISCSI_FIRST_BURST |
2391 ISCSI_MAX_BURST |
2392 ISCSI_PDU_INORDER_EN |
2393 ISCSI_DATASEQ_INORDER_EN |
2394 ISCSI_ERL |
2395 ISCSI_CONN_PORT |
2396 ISCSI_CONN_ADDRESS |
2397 ISCSI_EXP_STATSN |
2398 ISCSI_PERSISTENT_PORT |
2399 ISCSI_PERSISTENT_ADDRESS |
2400 ISCSI_TARGET_NAME |
2401 ISCSI_TPGT,
2402 .host_template = &iscsi_sht,
2403 .conndata_size = sizeof(struct iscsi_conn),
2404 .max_conn = 1,
2405 .max_cmd_len = ISCSI_TCP_MAX_CMD_LEN,
2406 /* session management */
2407 .create_session = iscsi_tcp_session_create,
2408 .destroy_session = iscsi_tcp_session_destroy,
2409 /* connection management */
2410 .create_conn = iscsi_tcp_conn_create,
2411 .bind_conn = iscsi_tcp_conn_bind,
2412 .destroy_conn = iscsi_tcp_conn_destroy,
2413 .set_param = iscsi_conn_set_param,
2414 .get_conn_param = iscsi_tcp_conn_get_param,
2415 .get_session_param = iscsi_session_get_param,
2416 .start_conn = iscsi_conn_start,
2417 .stop_conn = iscsi_conn_stop,
2418 /* these are called as part of conn recovery */
2419 .suspend_conn_recv = iscsi_tcp_suspend_conn_rx,
2420 .terminate_conn = iscsi_tcp_terminate_conn,
2421 /* IO */
2422 .send_pdu = iscsi_conn_send_pdu,
2423 .get_stats = iscsi_conn_get_stats,
2424 .init_cmd_task = iscsi_tcp_cmd_init,
2425 .init_mgmt_task = iscsi_tcp_mgmt_init,
2426 .xmit_cmd_task = iscsi_tcp_ctask_xmit,
2427 .xmit_mgmt_task = iscsi_tcp_mtask_xmit,
2428 .cleanup_cmd_task = iscsi_tcp_cleanup_ctask,
2429 /* recovery */
2430 .session_recovery_timedout = iscsi_session_recovery_timedout,
2431 };
2432
2433 static int __init
2434 iscsi_tcp_init(void)
2435 {
2436 if (iscsi_max_lun < 1) {
2437 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
2438 iscsi_max_lun);
2439 return -EINVAL;
2440 }
2441 iscsi_tcp_transport.max_lun = iscsi_max_lun;
2442
2443 if (!iscsi_register_transport(&iscsi_tcp_transport))
2444 return -ENODEV;
2445
2446 return 0;
2447 }
2448
2449 static void __exit
2450 iscsi_tcp_exit(void)
2451 {
2452 iscsi_unregister_transport(&iscsi_tcp_transport);
2453 }
2454
2455 module_init(iscsi_tcp_init);
2456 module_exit(iscsi_tcp_exit);