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[ALSA] Add model entry for Samsung X10 laptop
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / scsi / iscsi_tcp.c
blob66a1ae1d6982b209596cdf75e6ce6616b634f099
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/err.h>
30 #include <linux/types.h>
31 #include <linux/list.h>
32 #include <linux/inet.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 <linux/mutex.h>
39 #include <net/tcp.h>
40 #include <scsi/scsi_cmnd.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
47 MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
48 "Alex Aizman <itn780@yahoo.com>");
49 MODULE_DESCRIPTION("iSCSI/TCP data-path");
50 MODULE_LICENSE("GPL");
51 /* #define DEBUG_TCP */
52 #define DEBUG_ASSERT
53
54 #ifdef DEBUG_TCP
55 #define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
56 #else
57 #define debug_tcp(fmt...)
58 #endif
59
60 #ifndef DEBUG_ASSERT
61 #ifdef BUG_ON
62 #undef BUG_ON
63 #endif
64 #define BUG_ON(expr)
65 #endif
66
67 static unsigned int iscsi_max_lun = 512;
68 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
69
70 static inline void
71 iscsi_buf_init_iov(struct iscsi_buf *ibuf, char *vbuf, int size)
72 {
73 ibuf->sg.page = virt_to_page(vbuf);
74 ibuf->sg.offset = offset_in_page(vbuf);
75 ibuf->sg.length = size;
76 ibuf->sent = 0;
77 ibuf->use_sendmsg = 1;
78 }
79
80 static inline void
81 iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
82 {
83 ibuf->sg.page = sg->page;
84 ibuf->sg.offset = sg->offset;
85 ibuf->sg.length = sg->length;
86 /*
87 * Fastpath: sg element fits into single page
88 */
89 if (sg->length + sg->offset <= PAGE_SIZE && !PageSlab(sg->page))
90 ibuf->use_sendmsg = 0;
91 else
92 ibuf->use_sendmsg = 1;
93 ibuf->sent = 0;
94 }
95
96 static inline int
97 iscsi_buf_left(struct iscsi_buf *ibuf)
98 {
99 int rc;
100
101 rc = ibuf->sg.length - ibuf->sent;
102 BUG_ON(rc < 0);
103 return rc;
104 }
105
106 static inline void
107 iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
108 u8* crc)
109 {
110 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
111 struct hash_desc desc;
112
113 desc.tfm = tcp_conn->tx_tfm;
114 desc.flags = 0;
115 crypto_hash_digest(&desc, &buf->sg, buf->sg.length, crc);
116 buf->sg.length += sizeof(uint32_t);
117 }
118
119 static inline int
120 iscsi_hdr_extract(struct iscsi_tcp_conn *tcp_conn)
121 {
122 struct sk_buff *skb = tcp_conn->in.skb;
123
124 tcp_conn->in.zero_copy_hdr = 0;
125
126 if (tcp_conn->in.copy >= tcp_conn->hdr_size &&
127 tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER) {
128 /*
129 * Zero-copy PDU Header: using connection context
130 * to store header pointer.
131 */
132 if (skb_shinfo(skb)->frag_list == NULL &&
133 !skb_shinfo(skb)->nr_frags) {
134 tcp_conn->in.hdr = (struct iscsi_hdr *)
135 ((char*)skb->data + tcp_conn->in.offset);
136 tcp_conn->in.zero_copy_hdr = 1;
137 } else {
138 /* ignoring return code since we checked
139 * in.copy before */
140 skb_copy_bits(skb, tcp_conn->in.offset,
141 &tcp_conn->hdr, tcp_conn->hdr_size);
142 tcp_conn->in.hdr = &tcp_conn->hdr;
143 }
144 tcp_conn->in.offset += tcp_conn->hdr_size;
145 tcp_conn->in.copy -= tcp_conn->hdr_size;
146 } else {
147 int hdr_remains;
148 int copylen;
149
150 /*
151 * PDU header scattered across SKB's,
152 * copying it... This'll happen quite rarely.
153 */
154
155 if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER)
156 tcp_conn->in.hdr_offset = 0;
157
158 hdr_remains = tcp_conn->hdr_size - tcp_conn->in.hdr_offset;
159 BUG_ON(hdr_remains <= 0);
160
161 copylen = min(tcp_conn->in.copy, hdr_remains);
162 skb_copy_bits(skb, tcp_conn->in.offset,
163 (char*)&tcp_conn->hdr + tcp_conn->in.hdr_offset,
164 copylen);
165
166 debug_tcp("PDU gather offset %d bytes %d in.offset %d "
167 "in.copy %d\n", tcp_conn->in.hdr_offset, copylen,
168 tcp_conn->in.offset, tcp_conn->in.copy);
169
170 tcp_conn->in.offset += copylen;
171 tcp_conn->in.copy -= copylen;
172 if (copylen < hdr_remains) {
173 tcp_conn->in_progress = IN_PROGRESS_HEADER_GATHER;
174 tcp_conn->in.hdr_offset += copylen;
175 return -EAGAIN;
176 }
177 tcp_conn->in.hdr = &tcp_conn->hdr;
178 tcp_conn->discontiguous_hdr_cnt++;
179 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
180 }
181
182 return 0;
183 }
184
185 /*
186 * must be called with session lock
187 */
188 static void
189 iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
190 {
191 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
192 struct iscsi_r2t_info *r2t;
193 struct scsi_cmnd *sc;
194
195 /* flush ctask's r2t queues */
196 while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
197 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
198 sizeof(void*));
199 debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
200 }
201
202 sc = ctask->sc;
203 if (unlikely(!sc))
204 return;
205
206 tcp_ctask->xmstate = XMSTATE_IDLE;
207 tcp_ctask->r2t = NULL;
208 }
209
210 /**
211 * iscsi_data_rsp - SCSI Data-In Response processing
212 * @conn: iscsi connection
213 * @ctask: scsi command task
214 **/
215 static int
216 iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
217 {
218 int rc;
219 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
220 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
221 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
222 struct iscsi_session *session = conn->session;
223 int datasn = be32_to_cpu(rhdr->datasn);
224
225 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
226 if (rc)
227 return rc;
228 /*
229 * setup Data-In byte counter (gets decremented..)
230 */
231 ctask->data_count = tcp_conn->in.datalen;
232
233 if (tcp_conn->in.datalen == 0)
234 return 0;
235
236 if (ctask->datasn != datasn)
237 return ISCSI_ERR_DATASN;
238
239 ctask->datasn++;
240
241 tcp_ctask->data_offset = be32_to_cpu(rhdr->offset);
242 if (tcp_ctask->data_offset + tcp_conn->in.datalen > ctask->total_length)
243 return ISCSI_ERR_DATA_OFFSET;
244
245 if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
246 struct scsi_cmnd *sc = ctask->sc;
247
248 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
249 if (rhdr->flags & ISCSI_FLAG_DATA_UNDERFLOW) {
250 int res_count = be32_to_cpu(rhdr->residual_count);
251
252 if (res_count > 0 &&
253 res_count <= sc->request_bufflen) {
254 sc->resid = res_count;
255 sc->result = (DID_OK << 16) | rhdr->cmd_status;
256 } else
257 sc->result = (DID_BAD_TARGET << 16) |
258 rhdr->cmd_status;
259 } else if (rhdr->flags & ISCSI_FLAG_DATA_OVERFLOW) {
260 sc->resid = be32_to_cpu(rhdr->residual_count);
261 sc->result = (DID_OK << 16) | rhdr->cmd_status;
262 } else
263 sc->result = (DID_OK << 16) | rhdr->cmd_status;
264 }
265
266 conn->datain_pdus_cnt++;
267 return 0;
268 }
269
270 /**
271 * iscsi_solicit_data_init - initialize first Data-Out
272 * @conn: iscsi connection
273 * @ctask: scsi command task
274 * @r2t: R2T info
275 *
276 * Notes:
277 * Initialize first Data-Out within this R2T sequence and finds
278 * proper data_offset within this SCSI command.
279 *
280 * This function is called with connection lock taken.
281 **/
282 static void
283 iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
284 struct iscsi_r2t_info *r2t)
285 {
286 struct iscsi_data *hdr;
287 struct scsi_cmnd *sc = ctask->sc;
288 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
289
290 hdr = &r2t->dtask.hdr;
291 memset(hdr, 0, sizeof(struct iscsi_data));
292 hdr->ttt = r2t->ttt;
293 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
294 r2t->solicit_datasn++;
295 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
296 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
297 hdr->itt = ctask->hdr->itt;
298 hdr->exp_statsn = r2t->exp_statsn;
299 hdr->offset = cpu_to_be32(r2t->data_offset);
300 if (r2t->data_length > conn->max_xmit_dlength) {
301 hton24(hdr->dlength, conn->max_xmit_dlength);
302 r2t->data_count = conn->max_xmit_dlength;
303 hdr->flags = 0;
304 } else {
305 hton24(hdr->dlength, r2t->data_length);
306 r2t->data_count = r2t->data_length;
307 hdr->flags = ISCSI_FLAG_CMD_FINAL;
308 }
309 conn->dataout_pdus_cnt++;
310
311 r2t->sent = 0;
312
313 iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
314 sizeof(struct iscsi_hdr));
315
316 if (sc->use_sg) {
317 int i, sg_count = 0;
318 struct scatterlist *sg = sc->request_buffer;
319
320 r2t->sg = NULL;
321 for (i = 0; i < sc->use_sg; i++, sg += 1) {
322 /* FIXME: prefetch ? */
323 if (sg_count + sg->length > r2t->data_offset) {
324 int page_offset;
325
326 /* sg page found! */
327
328 /* offset within this page */
329 page_offset = r2t->data_offset - sg_count;
330
331 /* fill in this buffer */
332 iscsi_buf_init_sg(&r2t->sendbuf, sg);
333 r2t->sendbuf.sg.offset += page_offset;
334 r2t->sendbuf.sg.length -= page_offset;
335
336 /* xmit logic will continue with next one */
337 r2t->sg = sg + 1;
338 break;
339 }
340 sg_count += sg->length;
341 }
342 BUG_ON(r2t->sg == NULL);
343 } else
344 iscsi_buf_init_iov(&tcp_ctask->sendbuf,
345 (char*)sc->request_buffer + r2t->data_offset,
346 r2t->data_count);
347 }
348
349 /**
350 * iscsi_r2t_rsp - iSCSI R2T Response processing
351 * @conn: iscsi connection
352 * @ctask: scsi command task
353 **/
354 static int
355 iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
356 {
357 struct iscsi_r2t_info *r2t;
358 struct iscsi_session *session = conn->session;
359 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
360 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
361 struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
362 int r2tsn = be32_to_cpu(rhdr->r2tsn);
363 int rc;
364
365 if (tcp_conn->in.datalen)
366 return ISCSI_ERR_DATALEN;
367
368 if (tcp_ctask->exp_r2tsn && tcp_ctask->exp_r2tsn != r2tsn)
369 return ISCSI_ERR_R2TSN;
370
371 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
372 if (rc)
373 return rc;
374
375 /* FIXME: use R2TSN to detect missing R2T */
376
377 /* fill-in new R2T associated with the task */
378 spin_lock(&session->lock);
379 if (!ctask->sc || ctask->mtask ||
380 session->state != ISCSI_STATE_LOGGED_IN) {
381 printk(KERN_INFO "iscsi_tcp: dropping R2T itt %d in "
382 "recovery...\n", ctask->itt);
383 spin_unlock(&session->lock);
384 return 0;
385 }
386
387 rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
388 BUG_ON(!rc);
389
390 r2t->exp_statsn = rhdr->statsn;
391 r2t->data_length = be32_to_cpu(rhdr->data_length);
392 if (r2t->data_length == 0 ||
393 r2t->data_length > session->max_burst) {
394 spin_unlock(&session->lock);
395 return ISCSI_ERR_DATALEN;
396 }
397
398 r2t->data_offset = be32_to_cpu(rhdr->data_offset);
399 if (r2t->data_offset + r2t->data_length > ctask->total_length) {
400 spin_unlock(&session->lock);
401 return ISCSI_ERR_DATALEN;
402 }
403
404 r2t->ttt = rhdr->ttt; /* no flip */
405 r2t->solicit_datasn = 0;
406
407 iscsi_solicit_data_init(conn, ctask, r2t);
408
409 tcp_ctask->exp_r2tsn = r2tsn + 1;
410 tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
411 __kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
412 list_move_tail(&ctask->running, &conn->xmitqueue);
413
414 scsi_queue_work(session->host, &conn->xmitwork);
415 conn->r2t_pdus_cnt++;
416 spin_unlock(&session->lock);
417
418 return 0;
419 }
420
421 static int
422 iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
423 {
424 int rc = 0, opcode, ahslen;
425 struct iscsi_hdr *hdr;
426 struct iscsi_session *session = conn->session;
427 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
428 uint32_t cdgst, rdgst = 0, itt;
429
430 hdr = tcp_conn->in.hdr;
431
432 /* verify PDU length */
433 tcp_conn->in.datalen = ntoh24(hdr->dlength);
434 if (tcp_conn->in.datalen > conn->max_recv_dlength) {
435 printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
436 tcp_conn->in.datalen, conn->max_recv_dlength);
437 return ISCSI_ERR_DATALEN;
438 }
439 tcp_conn->data_copied = 0;
440
441 /* read AHS */
442 ahslen = hdr->hlength << 2;
443 tcp_conn->in.offset += ahslen;
444 tcp_conn->in.copy -= ahslen;
445 if (tcp_conn->in.copy < 0) {
446 printk(KERN_ERR "iscsi_tcp: can't handle AHS with length "
447 "%d bytes\n", ahslen);
448 return ISCSI_ERR_AHSLEN;
449 }
450
451 /* calculate read padding */
452 tcp_conn->in.padding = tcp_conn->in.datalen & (ISCSI_PAD_LEN-1);
453 if (tcp_conn->in.padding) {
454 tcp_conn->in.padding = ISCSI_PAD_LEN - tcp_conn->in.padding;
455 debug_scsi("read padding %d bytes\n", tcp_conn->in.padding);
456 }
457
458 if (conn->hdrdgst_en) {
459 struct hash_desc desc;
460 struct scatterlist sg;
461
462 sg_init_one(&sg, (u8 *)hdr,
463 sizeof(struct iscsi_hdr) + ahslen);
464 desc.tfm = tcp_conn->rx_tfm;
465 desc.flags = 0;
466 crypto_hash_digest(&desc, &sg, sg.length, (u8 *)&cdgst);
467 rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
468 ahslen);
469 if (cdgst != rdgst) {
470 printk(KERN_ERR "iscsi_tcp: hdrdgst error "
471 "recv 0x%x calc 0x%x\n", rdgst, cdgst);
472 return ISCSI_ERR_HDR_DGST;
473 }
474 }
475
476 opcode = hdr->opcode & ISCSI_OPCODE_MASK;
477 /* verify itt (itt encoding: age+cid+itt) */
478 rc = iscsi_verify_itt(conn, hdr, &itt);
479 if (rc == ISCSI_ERR_NO_SCSI_CMD) {
480 tcp_conn->in.datalen = 0; /* force drop */
481 return 0;
482 } else if (rc)
483 return rc;
484
485 debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
486 opcode, tcp_conn->in.offset, tcp_conn->in.copy,
487 ahslen, tcp_conn->in.datalen);
488
489 switch(opcode) {
490 case ISCSI_OP_SCSI_DATA_IN:
491 tcp_conn->in.ctask = session->cmds[itt];
492 rc = iscsi_data_rsp(conn, tcp_conn->in.ctask);
493 if (rc)
494 return rc;
495 /* fall through */
496 case ISCSI_OP_SCSI_CMD_RSP:
497 tcp_conn->in.ctask = session->cmds[itt];
498 if (tcp_conn->in.datalen)
499 goto copy_hdr;
500
501 spin_lock(&session->lock);
502 iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
503 rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
504 spin_unlock(&session->lock);
505 break;
506 case ISCSI_OP_R2T:
507 tcp_conn->in.ctask = session->cmds[itt];
508 if (ahslen)
509 rc = ISCSI_ERR_AHSLEN;
510 else if (tcp_conn->in.ctask->sc->sc_data_direction ==
511 DMA_TO_DEVICE)
512 rc = iscsi_r2t_rsp(conn, tcp_conn->in.ctask);
513 else
514 rc = ISCSI_ERR_PROTO;
515 break;
516 case ISCSI_OP_LOGIN_RSP:
517 case ISCSI_OP_TEXT_RSP:
518 case ISCSI_OP_REJECT:
519 case ISCSI_OP_ASYNC_EVENT:
520 /*
521 * It is possible that we could get a PDU with a buffer larger
522 * than 8K, but there are no targets that currently do this.
523 * For now we fail until we find a vendor that needs it
524 */
525 if (DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH <
526 tcp_conn->in.datalen) {
527 printk(KERN_ERR "iscsi_tcp: received buffer of len %u "
528 "but conn buffer is only %u (opcode %0x)\n",
529 tcp_conn->in.datalen,
530 DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, opcode);
531 rc = ISCSI_ERR_PROTO;
532 break;
533 }
534
535 if (tcp_conn->in.datalen)
536 goto copy_hdr;
537 /* fall through */
538 case ISCSI_OP_LOGOUT_RSP:
539 case ISCSI_OP_NOOP_IN:
540 case ISCSI_OP_SCSI_TMFUNC_RSP:
541 rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
542 break;
543 default:
544 rc = ISCSI_ERR_BAD_OPCODE;
545 break;
546 }
547
548 return rc;
549
550 copy_hdr:
551 /*
552 * if we did zero copy for the header but we will need multiple
553 * skbs to complete the command then we have to copy the header
554 * for later use
555 */
556 if (tcp_conn->in.zero_copy_hdr && tcp_conn->in.copy <=
557 (tcp_conn->in.datalen + tcp_conn->in.padding +
558 (conn->datadgst_en ? 4 : 0))) {
559 debug_tcp("Copying header for later use. in.copy %d in.datalen"
560 " %d\n", tcp_conn->in.copy, tcp_conn->in.datalen);
561 memcpy(&tcp_conn->hdr, tcp_conn->in.hdr,
562 sizeof(struct iscsi_hdr));
563 tcp_conn->in.hdr = &tcp_conn->hdr;
564 tcp_conn->in.zero_copy_hdr = 0;
565 }
566 return 0;
567 }
568
569 /**
570 * iscsi_ctask_copy - copy skb bits to the destanation cmd task
571 * @conn: iscsi tcp connection
572 * @ctask: scsi command task
573 * @buf: buffer to copy to
574 * @buf_size: size of buffer
575 * @offset: offset within the buffer
576 *
577 * Notes:
578 * The function calls skb_copy_bits() and updates per-connection and
579 * per-cmd byte counters.
580 *
581 * Read counters (in bytes):
582 *
583 * conn->in.offset offset within in progress SKB
584 * conn->in.copy left to copy from in progress SKB
585 * including padding
586 * conn->in.copied copied already from in progress SKB
587 * conn->data_copied copied already from in progress buffer
588 * ctask->sent total bytes sent up to the MidLayer
589 * ctask->data_count left to copy from in progress Data-In
590 * buf_left left to copy from in progress buffer
591 **/
592 static inline int
593 iscsi_ctask_copy(struct iscsi_tcp_conn *tcp_conn, struct iscsi_cmd_task *ctask,
594 void *buf, int buf_size, int offset)
595 {
596 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
597 int buf_left = buf_size - (tcp_conn->data_copied + offset);
598 int size = min(tcp_conn->in.copy, buf_left);
599 int rc;
600
601 size = min(size, ctask->data_count);
602
603 debug_tcp("ctask_copy %d bytes at offset %d copied %d\n",
604 size, tcp_conn->in.offset, tcp_conn->in.copied);
605
606 BUG_ON(size <= 0);
607 BUG_ON(tcp_ctask->sent + size > ctask->total_length);
608
609 rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
610 (char*)buf + (offset + tcp_conn->data_copied), size);
611 /* must fit into skb->len */
612 BUG_ON(rc);
613
614 tcp_conn->in.offset += size;
615 tcp_conn->in.copy -= size;
616 tcp_conn->in.copied += size;
617 tcp_conn->data_copied += size;
618 tcp_ctask->sent += size;
619 ctask->data_count -= size;
620
621 BUG_ON(tcp_conn->in.copy < 0);
622 BUG_ON(ctask->data_count < 0);
623
624 if (buf_size != (tcp_conn->data_copied + offset)) {
625 if (!ctask->data_count) {
626 BUG_ON(buf_size - tcp_conn->data_copied < 0);
627 /* done with this PDU */
628 return buf_size - tcp_conn->data_copied;
629 }
630 return -EAGAIN;
631 }
632
633 /* done with this buffer or with both - PDU and buffer */
634 tcp_conn->data_copied = 0;
635 return 0;
636 }
637
638 /**
639 * iscsi_tcp_copy - copy skb bits to the destanation buffer
640 * @conn: iscsi tcp connection
641 *
642 * Notes:
643 * The function calls skb_copy_bits() and updates per-connection
644 * byte counters.
645 **/
646 static inline int
647 iscsi_tcp_copy(struct iscsi_conn *conn)
648 {
649 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
650 int buf_size = tcp_conn->in.datalen;
651 int buf_left = buf_size - tcp_conn->data_copied;
652 int size = min(tcp_conn->in.copy, buf_left);
653 int rc;
654
655 debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
656 size, tcp_conn->in.offset, tcp_conn->data_copied);
657 BUG_ON(size <= 0);
658
659 rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
660 (char*)conn->data + tcp_conn->data_copied, size);
661 BUG_ON(rc);
662
663 tcp_conn->in.offset += size;
664 tcp_conn->in.copy -= size;
665 tcp_conn->in.copied += size;
666 tcp_conn->data_copied += size;
667
668 if (buf_size != tcp_conn->data_copied)
669 return -EAGAIN;
670
671 return 0;
672 }
673
674 static inline void
675 partial_sg_digest_update(struct iscsi_tcp_conn *tcp_conn,
676 struct scatterlist *sg, int offset, int length)
677 {
678 struct scatterlist temp;
679
680 memcpy(&temp, sg, sizeof(struct scatterlist));
681 temp.offset = offset;
682 temp.length = length;
683 crypto_hash_update(&tcp_conn->data_rx_hash, &temp, length);
684 }
685
686 static void
687 iscsi_recv_digest_update(struct iscsi_tcp_conn *tcp_conn, char* buf, int len)
688 {
689 struct scatterlist tmp;
690
691 sg_init_one(&tmp, buf, len);
692 crypto_hash_update(&tcp_conn->data_rx_hash, &tmp, len);
693 }
694
695 static int iscsi_scsi_data_in(struct iscsi_conn *conn)
696 {
697 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
698 struct iscsi_cmd_task *ctask = tcp_conn->in.ctask;
699 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
700 struct scsi_cmnd *sc = ctask->sc;
701 struct scatterlist *sg;
702 int i, offset, rc = 0;
703
704 BUG_ON((void*)ctask != sc->SCp.ptr);
705
706 /*
707 * copying Data-In into the Scsi_Cmnd
708 */
709 if (!sc->use_sg) {
710 i = ctask->data_count;
711 rc = iscsi_ctask_copy(tcp_conn, ctask, sc->request_buffer,
712 sc->request_bufflen,
713 tcp_ctask->data_offset);
714 if (rc == -EAGAIN)
715 return rc;
716 if (conn->datadgst_en)
717 iscsi_recv_digest_update(tcp_conn, sc->request_buffer,
718 i);
719 rc = 0;
720 goto done;
721 }
722
723 offset = tcp_ctask->data_offset;
724 sg = sc->request_buffer;
725
726 if (tcp_ctask->data_offset)
727 for (i = 0; i < tcp_ctask->sg_count; i++)
728 offset -= sg[i].length;
729 /* we've passed through partial sg*/
730 if (offset < 0)
731 offset = 0;
732
733 for (i = tcp_ctask->sg_count; i < sc->use_sg; i++) {
734 char *dest;
735
736 dest = kmap_atomic(sg[i].page, KM_SOFTIRQ0);
737 rc = iscsi_ctask_copy(tcp_conn, ctask, dest + sg[i].offset,
738 sg[i].length, offset);
739 kunmap_atomic(dest, KM_SOFTIRQ0);
740 if (rc == -EAGAIN)
741 /* continue with the next SKB/PDU */
742 return rc;
743 if (!rc) {
744 if (conn->datadgst_en) {
745 if (!offset)
746 crypto_hash_update(
747 &tcp_conn->data_rx_hash,
748 &sg[i], sg[i].length);
749 else
750 partial_sg_digest_update(tcp_conn,
751 &sg[i],
752 sg[i].offset + offset,
753 sg[i].length - offset);
754 }
755 offset = 0;
756 tcp_ctask->sg_count++;
757 }
758
759 if (!ctask->data_count) {
760 if (rc && conn->datadgst_en)
761 /*
762 * data-in is complete, but buffer not...
763 */
764 partial_sg_digest_update(tcp_conn, &sg[i],
765 sg[i].offset, sg[i].length-rc);
766 rc = 0;
767 break;
768 }
769
770 if (!tcp_conn->in.copy)
771 return -EAGAIN;
772 }
773 BUG_ON(ctask->data_count);
774
775 done:
776 /* check for non-exceptional status */
777 if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
778 debug_scsi("done [sc %lx res %d itt 0x%x flags 0x%x]\n",
779 (long)sc, sc->result, ctask->itt,
780 tcp_conn->in.hdr->flags);
781 spin_lock(&conn->session->lock);
782 iscsi_tcp_cleanup_ctask(conn, ctask);
783 __iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
784 spin_unlock(&conn->session->lock);
785 }
786
787 return rc;
788 }
789
790 static int
791 iscsi_data_recv(struct iscsi_conn *conn)
792 {
793 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
794 int rc = 0, opcode;
795
796 opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
797 switch (opcode) {
798 case ISCSI_OP_SCSI_DATA_IN:
799 rc = iscsi_scsi_data_in(conn);
800 break;
801 case ISCSI_OP_SCSI_CMD_RSP:
802 spin_lock(&conn->session->lock);
803 iscsi_tcp_cleanup_ctask(conn, tcp_conn->in.ctask);
804 spin_unlock(&conn->session->lock);
805 case ISCSI_OP_TEXT_RSP:
806 case ISCSI_OP_LOGIN_RSP:
807 case ISCSI_OP_ASYNC_EVENT:
808 case ISCSI_OP_REJECT:
809 /*
810 * Collect data segment to the connection's data
811 * placeholder
812 */
813 if (iscsi_tcp_copy(conn)) {
814 rc = -EAGAIN;
815 goto exit;
816 }
817
818 rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, conn->data,
819 tcp_conn->in.datalen);
820 if (!rc && conn->datadgst_en && opcode != ISCSI_OP_LOGIN_RSP)
821 iscsi_recv_digest_update(tcp_conn, conn->data,
822 tcp_conn->in.datalen);
823 break;
824 default:
825 BUG_ON(1);
826 }
827 exit:
828 return rc;
829 }
830
831 /**
832 * iscsi_tcp_data_recv - TCP receive in sendfile fashion
833 * @rd_desc: read descriptor
834 * @skb: socket buffer
835 * @offset: offset in skb
836 * @len: skb->len - offset
837 **/
838 static int
839 iscsi_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
840 unsigned int offset, size_t len)
841 {
842 int rc;
843 struct iscsi_conn *conn = rd_desc->arg.data;
844 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
845 int processed;
846 char pad[ISCSI_PAD_LEN];
847 struct scatterlist sg;
848
849 /*
850 * Save current SKB and its offset in the corresponding
851 * connection context.
852 */
853 tcp_conn->in.copy = skb->len - offset;
854 tcp_conn->in.offset = offset;
855 tcp_conn->in.skb = skb;
856 tcp_conn->in.len = tcp_conn->in.copy;
857 BUG_ON(tcp_conn->in.copy <= 0);
858 debug_tcp("in %d bytes\n", tcp_conn->in.copy);
859
860 more:
861 tcp_conn->in.copied = 0;
862 rc = 0;
863
864 if (unlikely(conn->suspend_rx)) {
865 debug_tcp("conn %d Rx suspended!\n", conn->id);
866 return 0;
867 }
868
869 if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER ||
870 tcp_conn->in_progress == IN_PROGRESS_HEADER_GATHER) {
871 rc = iscsi_hdr_extract(tcp_conn);
872 if (rc) {
873 if (rc == -EAGAIN)
874 goto nomore;
875 else {
876 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
877 return 0;
878 }
879 }
880
881 /*
882 * Verify and process incoming PDU header.
883 */
884 rc = iscsi_tcp_hdr_recv(conn);
885 if (!rc && tcp_conn->in.datalen) {
886 if (conn->datadgst_en) {
887 crypto_hash_init(&tcp_conn->data_rx_hash);
888 }
889 tcp_conn->in_progress = IN_PROGRESS_DATA_RECV;
890 } else if (rc) {
891 iscsi_conn_failure(conn, rc);
892 return 0;
893 }
894 }
895
896 if (tcp_conn->in_progress == IN_PROGRESS_DDIGEST_RECV) {
897 uint32_t recv_digest;
898
899 debug_tcp("extra data_recv offset %d copy %d\n",
900 tcp_conn->in.offset, tcp_conn->in.copy);
901 skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
902 &recv_digest, 4);
903 tcp_conn->in.offset += 4;
904 tcp_conn->in.copy -= 4;
905 if (recv_digest != tcp_conn->in.datadgst) {
906 debug_tcp("iscsi_tcp: data digest error!"
907 "0x%x != 0x%x\n", recv_digest,
908 tcp_conn->in.datadgst);
909 iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
910 return 0;
911 } else {
912 debug_tcp("iscsi_tcp: data digest match!"
913 "0x%x == 0x%x\n", recv_digest,
914 tcp_conn->in.datadgst);
915 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
916 }
917 }
918
919 if (tcp_conn->in_progress == IN_PROGRESS_DATA_RECV &&
920 tcp_conn->in.copy) {
921
922 debug_tcp("data_recv offset %d copy %d\n",
923 tcp_conn->in.offset, tcp_conn->in.copy);
924
925 rc = iscsi_data_recv(conn);
926 if (rc) {
927 if (rc == -EAGAIN)
928 goto again;
929 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
930 return 0;
931 }
932 tcp_conn->in.copy -= tcp_conn->in.padding;
933 tcp_conn->in.offset += tcp_conn->in.padding;
934 if (conn->datadgst_en) {
935 if (tcp_conn->in.padding) {
936 debug_tcp("padding -> %d\n",
937 tcp_conn->in.padding);
938 memset(pad, 0, tcp_conn->in.padding);
939 sg_init_one(&sg, pad, tcp_conn->in.padding);
940 crypto_hash_update(&tcp_conn->data_rx_hash,
941 &sg, sg.length);
942 }
943 crypto_hash_final(&tcp_conn->data_rx_hash,
944 (u8 *)&tcp_conn->in.datadgst);
945 debug_tcp("rx digest 0x%x\n", tcp_conn->in.datadgst);
946 tcp_conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
947 } else
948 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
949 }
950
951 debug_tcp("f, processed %d from out of %d padding %d\n",
952 tcp_conn->in.offset - offset, (int)len, tcp_conn->in.padding);
953 BUG_ON(tcp_conn->in.offset - offset > len);
954
955 if (tcp_conn->in.offset - offset != len) {
956 debug_tcp("continue to process %d bytes\n",
957 (int)len - (tcp_conn->in.offset - offset));
958 goto more;
959 }
960
961 nomore:
962 processed = tcp_conn->in.offset - offset;
963 BUG_ON(processed == 0);
964 return processed;
965
966 again:
967 processed = tcp_conn->in.offset - offset;
968 debug_tcp("c, processed %d from out of %d rd_desc_cnt %d\n",
969 processed, (int)len, (int)rd_desc->count);
970 BUG_ON(processed == 0);
971 BUG_ON(processed > len);
972
973 conn->rxdata_octets += processed;
974 return processed;
975 }
976
977 static void
978 iscsi_tcp_data_ready(struct sock *sk, int flag)
979 {
980 struct iscsi_conn *conn = sk->sk_user_data;
981 read_descriptor_t rd_desc;
982
983 read_lock(&sk->sk_callback_lock);
984
985 /*
986 * Use rd_desc to pass 'conn' to iscsi_tcp_data_recv.
987 * We set count to 1 because we want the network layer to
988 * hand us all the skbs that are available. iscsi_tcp_data_recv
989 * handled pdus that cross buffers or pdus that still need data.
990 */
991 rd_desc.arg.data = conn;
992 rd_desc.count = 1;
993 tcp_read_sock(sk, &rd_desc, iscsi_tcp_data_recv);
994
995 read_unlock(&sk->sk_callback_lock);
996 }
997
998 static void
999 iscsi_tcp_state_change(struct sock *sk)
1000 {
1001 struct iscsi_tcp_conn *tcp_conn;
1002 struct iscsi_conn *conn;
1003 struct iscsi_session *session;
1004 void (*old_state_change)(struct sock *);
1005
1006 read_lock(&sk->sk_callback_lock);
1007
1008 conn = (struct iscsi_conn*)sk->sk_user_data;
1009 session = conn->session;
1010
1011 if ((sk->sk_state == TCP_CLOSE_WAIT ||
1012 sk->sk_state == TCP_CLOSE) &&
1013 !atomic_read(&sk->sk_rmem_alloc)) {
1014 debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
1015 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1016 }
1017
1018 tcp_conn = conn->dd_data;
1019 old_state_change = tcp_conn->old_state_change;
1020
1021 read_unlock(&sk->sk_callback_lock);
1022
1023 old_state_change(sk);
1024 }
1025
1026 /**
1027 * iscsi_write_space - Called when more output buffer space is available
1028 * @sk: socket space is available for
1029 **/
1030 static void
1031 iscsi_write_space(struct sock *sk)
1032 {
1033 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
1034 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1035
1036 tcp_conn->old_write_space(sk);
1037 debug_tcp("iscsi_write_space: cid %d\n", conn->id);
1038 scsi_queue_work(conn->session->host, &conn->xmitwork);
1039 }
1040
1041 static void
1042 iscsi_conn_set_callbacks(struct iscsi_conn *conn)
1043 {
1044 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1045 struct sock *sk = tcp_conn->sock->sk;
1046
1047 /* assign new callbacks */
1048 write_lock_bh(&sk->sk_callback_lock);
1049 sk->sk_user_data = conn;
1050 tcp_conn->old_data_ready = sk->sk_data_ready;
1051 tcp_conn->old_state_change = sk->sk_state_change;
1052 tcp_conn->old_write_space = sk->sk_write_space;
1053 sk->sk_data_ready = iscsi_tcp_data_ready;
1054 sk->sk_state_change = iscsi_tcp_state_change;
1055 sk->sk_write_space = iscsi_write_space;
1056 write_unlock_bh(&sk->sk_callback_lock);
1057 }
1058
1059 static void
1060 iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
1061 {
1062 struct sock *sk = tcp_conn->sock->sk;
1063
1064 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
1065 write_lock_bh(&sk->sk_callback_lock);
1066 sk->sk_user_data = NULL;
1067 sk->sk_data_ready = tcp_conn->old_data_ready;
1068 sk->sk_state_change = tcp_conn->old_state_change;
1069 sk->sk_write_space = tcp_conn->old_write_space;
1070 sk->sk_no_check = 0;
1071 write_unlock_bh(&sk->sk_callback_lock);
1072 }
1073
1074 /**
1075 * iscsi_send - generic send routine
1076 * @sk: kernel's socket
1077 * @buf: buffer to write from
1078 * @size: actual size to write
1079 * @flags: socket's flags
1080 */
1081 static inline int
1082 iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
1083 {
1084 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1085 struct socket *sk = tcp_conn->sock;
1086 int offset = buf->sg.offset + buf->sent, res;
1087
1088 /*
1089 * if we got use_sg=0 or are sending something we kmallocd
1090 * then we did not have to do kmap (kmap returns page_address)
1091 *
1092 * if we got use_sg > 0, but had to drop down, we do not
1093 * set clustering so this should only happen for that
1094 * slab case.
1095 */
1096 if (buf->use_sendmsg)
1097 res = sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
1098 else
1099 res = tcp_conn->sendpage(sk, buf->sg.page, offset, size, flags);
1100
1101 if (res >= 0) {
1102 conn->txdata_octets += res;
1103 buf->sent += res;
1104 return res;
1105 }
1106
1107 tcp_conn->sendpage_failures_cnt++;
1108 if (res == -EAGAIN)
1109 res = -ENOBUFS;
1110 else
1111 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1112 return res;
1113 }
1114
1115 /**
1116 * iscsi_sendhdr - send PDU Header via tcp_sendpage()
1117 * @conn: iscsi connection
1118 * @buf: buffer to write from
1119 * @datalen: lenght of data to be sent after the header
1120 *
1121 * Notes:
1122 * (Tx, Fast Path)
1123 **/
1124 static inline int
1125 iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
1126 {
1127 int flags = 0; /* MSG_DONTWAIT; */
1128 int res, size;
1129
1130 size = buf->sg.length - buf->sent;
1131 BUG_ON(buf->sent + size > buf->sg.length);
1132 if (buf->sent + size != buf->sg.length || datalen)
1133 flags |= MSG_MORE;
1134
1135 res = iscsi_send(conn, buf, size, flags);
1136 debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
1137 if (res >= 0) {
1138 if (size != res)
1139 return -EAGAIN;
1140 return 0;
1141 }
1142
1143 return res;
1144 }
1145
1146 /**
1147 * iscsi_sendpage - send one page of iSCSI Data-Out.
1148 * @conn: iscsi connection
1149 * @buf: buffer to write from
1150 * @count: remaining data
1151 * @sent: number of bytes sent
1152 *
1153 * Notes:
1154 * (Tx, Fast Path)
1155 **/
1156 static inline int
1157 iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
1158 int *count, int *sent)
1159 {
1160 int flags = 0; /* MSG_DONTWAIT; */
1161 int res, size;
1162
1163 size = buf->sg.length - buf->sent;
1164 BUG_ON(buf->sent + size > buf->sg.length);
1165 if (size > *count)
1166 size = *count;
1167 if (buf->sent + size != buf->sg.length || *count != size)
1168 flags |= MSG_MORE;
1169
1170 res = iscsi_send(conn, buf, size, flags);
1171 debug_tcp("sendpage: %d bytes, sent %d left %d sent %d res %d\n",
1172 size, buf->sent, *count, *sent, res);
1173 if (res >= 0) {
1174 *count -= res;
1175 *sent += res;
1176 if (size != res)
1177 return -EAGAIN;
1178 return 0;
1179 }
1180
1181 return res;
1182 }
1183
1184 static inline void
1185 iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
1186 struct iscsi_cmd_task *ctask)
1187 {
1188 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1189
1190 crypto_hash_init(&tcp_conn->data_tx_hash);
1191 tcp_ctask->digest_count = 4;
1192 }
1193
1194 static int
1195 iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1196 struct iscsi_buf *buf, uint32_t *digest, int final)
1197 {
1198 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1199 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1200 int rc = 0;
1201 int sent = 0;
1202
1203 if (final)
1204 crypto_hash_final(&tcp_conn->data_tx_hash, (u8 *)digest);
1205
1206 iscsi_buf_init_iov(buf, (char*)digest, 4);
1207 rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
1208 if (rc) {
1209 tcp_ctask->datadigest = *digest;
1210 tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
1211 } else
1212 tcp_ctask->digest_count = 4;
1213 return rc;
1214 }
1215
1216 /**
1217 * iscsi_solicit_data_cont - initialize next Data-Out
1218 * @conn: iscsi connection
1219 * @ctask: scsi command task
1220 * @r2t: R2T info
1221 * @left: bytes left to transfer
1222 *
1223 * Notes:
1224 * Initialize next Data-Out within this R2T sequence and continue
1225 * to process next Scatter-Gather element(if any) of this SCSI command.
1226 *
1227 * Called under connection lock.
1228 **/
1229 static void
1230 iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1231 struct iscsi_r2t_info *r2t, int left)
1232 {
1233 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1234 struct iscsi_data *hdr;
1235 struct scsi_cmnd *sc = ctask->sc;
1236 int new_offset;
1237
1238 hdr = &r2t->dtask.hdr;
1239 memset(hdr, 0, sizeof(struct iscsi_data));
1240 hdr->ttt = r2t->ttt;
1241 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
1242 r2t->solicit_datasn++;
1243 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
1244 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
1245 hdr->itt = ctask->hdr->itt;
1246 hdr->exp_statsn = r2t->exp_statsn;
1247 new_offset = r2t->data_offset + r2t->sent;
1248 hdr->offset = cpu_to_be32(new_offset);
1249 if (left > conn->max_xmit_dlength) {
1250 hton24(hdr->dlength, conn->max_xmit_dlength);
1251 r2t->data_count = conn->max_xmit_dlength;
1252 } else {
1253 hton24(hdr->dlength, left);
1254 r2t->data_count = left;
1255 hdr->flags = ISCSI_FLAG_CMD_FINAL;
1256 }
1257 conn->dataout_pdus_cnt++;
1258
1259 iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
1260 sizeof(struct iscsi_hdr));
1261
1262 if (sc->use_sg && !iscsi_buf_left(&r2t->sendbuf)) {
1263 BUG_ON(tcp_ctask->bad_sg == r2t->sg);
1264 iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
1265 r2t->sg += 1;
1266 } else
1267 iscsi_buf_init_iov(&tcp_ctask->sendbuf,
1268 (char*)sc->request_buffer + new_offset,
1269 r2t->data_count);
1270 }
1271
1272 static void
1273 iscsi_unsolicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1274 {
1275 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1276 struct iscsi_data_task *dtask;
1277
1278 dtask = tcp_ctask->dtask = &tcp_ctask->unsol_dtask;
1279 iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr,
1280 tcp_ctask->r2t_data_count);
1281 iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
1282 sizeof(struct iscsi_hdr));
1283 }
1284
1285 /**
1286 * iscsi_tcp_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
1287 * @conn: iscsi connection
1288 * @ctask: scsi command task
1289 * @sc: scsi command
1290 **/
1291 static void
1292 iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
1293 {
1294 struct scsi_cmnd *sc = ctask->sc;
1295 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1296
1297 BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
1298
1299 tcp_ctask->sent = 0;
1300 tcp_ctask->sg_count = 0;
1301
1302 if (sc->sc_data_direction == DMA_TO_DEVICE) {
1303 tcp_ctask->xmstate = XMSTATE_W_HDR;
1304 tcp_ctask->exp_r2tsn = 0;
1305 BUG_ON(ctask->total_length == 0);
1306
1307 if (sc->use_sg) {
1308 struct scatterlist *sg = sc->request_buffer;
1309
1310 iscsi_buf_init_sg(&tcp_ctask->sendbuf,
1311 &sg[tcp_ctask->sg_count++]);
1312 tcp_ctask->sg = sg;
1313 tcp_ctask->bad_sg = sg + sc->use_sg;
1314 } else
1315 iscsi_buf_init_iov(&tcp_ctask->sendbuf,
1316 sc->request_buffer,
1317 sc->request_bufflen);
1318
1319 if (ctask->imm_count)
1320 tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
1321
1322 tcp_ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
1323 if (tcp_ctask->pad_count) {
1324 tcp_ctask->pad_count = ISCSI_PAD_LEN -
1325 tcp_ctask->pad_count;
1326 debug_scsi("write padding %d bytes\n",
1327 tcp_ctask->pad_count);
1328 tcp_ctask->xmstate |= XMSTATE_W_PAD;
1329 }
1330
1331 if (ctask->unsol_count)
1332 tcp_ctask->xmstate |= XMSTATE_UNS_HDR |
1333 XMSTATE_UNS_INIT;
1334 tcp_ctask->r2t_data_count = ctask->total_length -
1335 ctask->imm_count -
1336 ctask->unsol_count;
1337
1338 debug_scsi("cmd [itt 0x%x total %d imm %d imm_data %d "
1339 "r2t_data %d]\n",
1340 ctask->itt, ctask->total_length, ctask->imm_count,
1341 ctask->unsol_count, tcp_ctask->r2t_data_count);
1342 } else
1343 tcp_ctask->xmstate = XMSTATE_R_HDR;
1344
1345 iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
1346 sizeof(struct iscsi_hdr));
1347 }
1348
1349 /**
1350 * iscsi_tcp_mtask_xmit - xmit management(immediate) task
1351 * @conn: iscsi connection
1352 * @mtask: task management task
1353 *
1354 * Notes:
1355 * The function can return -EAGAIN in which case caller must
1356 * call it again later, or recover. '0' return code means successful
1357 * xmit.
1358 *
1359 * Management xmit state machine consists of two states:
1360 * IN_PROGRESS_IMM_HEAD - PDU Header xmit in progress
1361 * IN_PROGRESS_IMM_DATA - PDU Data xmit in progress
1362 **/
1363 static int
1364 iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
1365 {
1366 struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
1367 int rc;
1368
1369 debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
1370 conn->id, tcp_mtask->xmstate, mtask->itt);
1371
1372 if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
1373 tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
1374 if (mtask->data_count)
1375 tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
1376 if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
1377 conn->stop_stage != STOP_CONN_RECOVER &&
1378 conn->hdrdgst_en)
1379 iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
1380 (u8*)tcp_mtask->hdrext);
1381 rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
1382 mtask->data_count);
1383 if (rc) {
1384 tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
1385 if (mtask->data_count)
1386 tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
1387 return rc;
1388 }
1389 }
1390
1391 if (tcp_mtask->xmstate & XMSTATE_IMM_DATA) {
1392 BUG_ON(!mtask->data_count);
1393 tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
1394 /* FIXME: implement.
1395 * Virtual buffer could be spreaded across multiple pages...
1396 */
1397 do {
1398 int rc;
1399
1400 rc = iscsi_sendpage(conn, &tcp_mtask->sendbuf,
1401 &mtask->data_count, &tcp_mtask->sent);
1402 if (rc) {
1403 tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
1404 return rc;
1405 }
1406 } while (mtask->data_count);
1407 }
1408
1409 BUG_ON(tcp_mtask->xmstate != XMSTATE_IDLE);
1410 if (mtask->hdr->itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1411 struct iscsi_session *session = conn->session;
1412
1413 spin_lock_bh(&session->lock);
1414 list_del(&conn->mtask->running);
1415 __kfifo_put(session->mgmtpool.queue, (void*)&conn->mtask,
1416 sizeof(void*));
1417 spin_unlock_bh(&session->lock);
1418 }
1419 return 0;
1420 }
1421
1422 static inline int
1423 handle_xmstate_r_hdr(struct iscsi_conn *conn,
1424 struct iscsi_tcp_cmd_task *tcp_ctask)
1425 {
1426 int rc;
1427
1428 tcp_ctask->xmstate &= ~XMSTATE_R_HDR;
1429 if (conn->hdrdgst_en)
1430 iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
1431 (u8*)tcp_ctask->hdrext);
1432 rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, 0);
1433 if (!rc) {
1434 BUG_ON(tcp_ctask->xmstate != XMSTATE_IDLE);
1435 return 0; /* wait for Data-In */
1436 }
1437 tcp_ctask->xmstate |= XMSTATE_R_HDR;
1438 return rc;
1439 }
1440
1441 static inline int
1442 handle_xmstate_w_hdr(struct iscsi_conn *conn,
1443 struct iscsi_cmd_task *ctask)
1444 {
1445 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1446 int rc;
1447
1448 tcp_ctask->xmstate &= ~XMSTATE_W_HDR;
1449 if (conn->hdrdgst_en)
1450 iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
1451 (u8*)tcp_ctask->hdrext);
1452 rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
1453 if (rc)
1454 tcp_ctask->xmstate |= XMSTATE_W_HDR;
1455 return rc;
1456 }
1457
1458 static inline int
1459 handle_xmstate_data_digest(struct iscsi_conn *conn,
1460 struct iscsi_cmd_task *ctask)
1461 {
1462 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1463 int rc;
1464
1465 tcp_ctask->xmstate &= ~XMSTATE_DATA_DIGEST;
1466 debug_tcp("resent data digest 0x%x\n", tcp_ctask->datadigest);
1467 rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
1468 &tcp_ctask->datadigest, 0);
1469 if (rc) {
1470 tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
1471 debug_tcp("resent data digest 0x%x fail!\n",
1472 tcp_ctask->datadigest);
1473 }
1474
1475 return rc;
1476 }
1477
1478 static inline int
1479 handle_xmstate_imm_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1480 {
1481 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1482 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1483 int rc;
1484
1485 BUG_ON(!ctask->imm_count);
1486 tcp_ctask->xmstate &= ~XMSTATE_IMM_DATA;
1487
1488 if (conn->datadgst_en) {
1489 iscsi_data_digest_init(tcp_conn, ctask);
1490 tcp_ctask->immdigest = 0;
1491 }
1492
1493 for (;;) {
1494 rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
1495 &ctask->imm_count, &tcp_ctask->sent);
1496 if (rc) {
1497 tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
1498 if (conn->datadgst_en) {
1499 crypto_hash_final(&tcp_conn->data_tx_hash,
1500 (u8 *)&tcp_ctask->immdigest);
1501 debug_tcp("tx imm sendpage fail 0x%x\n",
1502 tcp_ctask->datadigest);
1503 }
1504 return rc;
1505 }
1506 if (conn->datadgst_en)
1507 crypto_hash_update(&tcp_conn->data_tx_hash,
1508 &tcp_ctask->sendbuf.sg,
1509 tcp_ctask->sendbuf.sg.length);
1510
1511 if (!ctask->imm_count)
1512 break;
1513 iscsi_buf_init_sg(&tcp_ctask->sendbuf,
1514 &tcp_ctask->sg[tcp_ctask->sg_count++]);
1515 }
1516
1517 if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
1518 rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
1519 &tcp_ctask->immdigest, 1);
1520 if (rc) {
1521 debug_tcp("sending imm digest 0x%x fail!\n",
1522 tcp_ctask->immdigest);
1523 return rc;
1524 }
1525 debug_tcp("sending imm digest 0x%x\n", tcp_ctask->immdigest);
1526 }
1527
1528 return 0;
1529 }
1530
1531 static inline int
1532 handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1533 {
1534 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1535 struct iscsi_data_task *dtask;
1536 int rc;
1537
1538 tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
1539 if (tcp_ctask->xmstate & XMSTATE_UNS_INIT) {
1540 iscsi_unsolicit_data_init(conn, ctask);
1541 dtask = tcp_ctask->dtask;
1542 if (conn->hdrdgst_en)
1543 iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
1544 (u8*)dtask->hdrext);
1545 tcp_ctask->xmstate &= ~XMSTATE_UNS_INIT;
1546 }
1547
1548 rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->data_count);
1549 if (rc) {
1550 tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
1551 tcp_ctask->xmstate |= XMSTATE_UNS_HDR;
1552 return rc;
1553 }
1554
1555 debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
1556 ctask->itt, ctask->unsol_count, tcp_ctask->sent);
1557 return 0;
1558 }
1559
1560 static inline int
1561 handle_xmstate_uns_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1562 {
1563 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1564 struct iscsi_data_task *dtask = tcp_ctask->dtask;
1565 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1566 int rc;
1567
1568 BUG_ON(!ctask->data_count);
1569 tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
1570
1571 if (conn->datadgst_en) {
1572 iscsi_data_digest_init(tcp_conn, ctask);
1573 dtask->digest = 0;
1574 }
1575
1576 for (;;) {
1577 int start = tcp_ctask->sent;
1578
1579 rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
1580 &ctask->data_count, &tcp_ctask->sent);
1581 if (rc) {
1582 ctask->unsol_count -= tcp_ctask->sent - start;
1583 tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
1584 /* will continue with this ctask later.. */
1585 if (conn->datadgst_en) {
1586 crypto_hash_final(&tcp_conn->data_tx_hash,
1587 (u8 *)&dtask->digest);
1588 debug_tcp("tx uns data fail 0x%x\n",
1589 dtask->digest);
1590 }
1591 return rc;
1592 }
1593
1594 BUG_ON(tcp_ctask->sent > ctask->total_length);
1595 ctask->unsol_count -= tcp_ctask->sent - start;
1596
1597 /*
1598 * XXX:we may run here with un-initial sendbuf.
1599 * so pass it
1600 */
1601 if (conn->datadgst_en && tcp_ctask->sent - start > 0)
1602 crypto_hash_update(&tcp_conn->data_tx_hash,
1603 &tcp_ctask->sendbuf.sg,
1604 tcp_ctask->sendbuf.sg.length);
1605
1606 if (!ctask->data_count)
1607 break;
1608 iscsi_buf_init_sg(&tcp_ctask->sendbuf,
1609 &tcp_ctask->sg[tcp_ctask->sg_count++]);
1610 }
1611 BUG_ON(ctask->unsol_count < 0);
1612
1613 /*
1614 * Done with the Data-Out. Next, check if we need
1615 * to send another unsolicited Data-Out.
1616 */
1617 if (ctask->unsol_count) {
1618 if (conn->datadgst_en) {
1619 rc = iscsi_digest_final_send(conn, ctask,
1620 &dtask->digestbuf,
1621 &dtask->digest, 1);
1622 if (rc) {
1623 debug_tcp("send uns digest 0x%x fail\n",
1624 dtask->digest);
1625 return rc;
1626 }
1627 debug_tcp("sending uns digest 0x%x, more uns\n",
1628 dtask->digest);
1629 }
1630 tcp_ctask->xmstate |= XMSTATE_UNS_INIT;
1631 return 1;
1632 }
1633
1634 if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
1635 rc = iscsi_digest_final_send(conn, ctask,
1636 &dtask->digestbuf,
1637 &dtask->digest, 1);
1638 if (rc) {
1639 debug_tcp("send last uns digest 0x%x fail\n",
1640 dtask->digest);
1641 return rc;
1642 }
1643 debug_tcp("sending uns digest 0x%x\n",dtask->digest);
1644 }
1645
1646 return 0;
1647 }
1648
1649 static inline int
1650 handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1651 {
1652 struct iscsi_session *session = conn->session;
1653 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1654 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1655 struct iscsi_r2t_info *r2t = tcp_ctask->r2t;
1656 struct iscsi_data_task *dtask = &r2t->dtask;
1657 int left, rc;
1658
1659 tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
1660 tcp_ctask->dtask = dtask;
1661
1662 if (conn->datadgst_en) {
1663 iscsi_data_digest_init(tcp_conn, ctask);
1664 dtask->digest = 0;
1665 }
1666 solicit_again:
1667 /*
1668 * send Data-Out within this R2T sequence.
1669 */
1670 if (!r2t->data_count)
1671 goto data_out_done;
1672
1673 rc = iscsi_sendpage(conn, &r2t->sendbuf, &r2t->data_count, &r2t->sent);
1674 if (rc) {
1675 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1676 /* will continue with this ctask later.. */
1677 if (conn->datadgst_en) {
1678 crypto_hash_final(&tcp_conn->data_tx_hash,
1679 (u8 *)&dtask->digest);
1680 debug_tcp("r2t data send fail 0x%x\n", dtask->digest);
1681 }
1682 return rc;
1683 }
1684
1685 BUG_ON(r2t->data_count < 0);
1686 if (conn->datadgst_en)
1687 crypto_hash_update(&tcp_conn->data_tx_hash, &r2t->sendbuf.sg,
1688 r2t->sendbuf.sg.length);
1689
1690 if (r2t->data_count) {
1691 BUG_ON(ctask->sc->use_sg == 0);
1692 if (!iscsi_buf_left(&r2t->sendbuf)) {
1693 BUG_ON(tcp_ctask->bad_sg == r2t->sg);
1694 iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
1695 r2t->sg += 1;
1696 }
1697 goto solicit_again;
1698 }
1699
1700 data_out_done:
1701 /*
1702 * Done with this Data-Out. Next, check if we have
1703 * to send another Data-Out for this R2T.
1704 */
1705 BUG_ON(r2t->data_length - r2t->sent < 0);
1706 left = r2t->data_length - r2t->sent;
1707 if (left) {
1708 if (conn->datadgst_en) {
1709 rc = iscsi_digest_final_send(conn, ctask,
1710 &dtask->digestbuf,
1711 &dtask->digest, 1);
1712 if (rc) {
1713 debug_tcp("send r2t data digest 0x%x"
1714 "fail\n", dtask->digest);
1715 return rc;
1716 }
1717 debug_tcp("r2t data send digest 0x%x\n",
1718 dtask->digest);
1719 }
1720 iscsi_solicit_data_cont(conn, ctask, r2t, left);
1721 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1722 tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1723 return 1;
1724 }
1725
1726 /*
1727 * Done with this R2T. Check if there are more
1728 * outstanding R2Ts ready to be processed.
1729 */
1730 BUG_ON(tcp_ctask->r2t_data_count - r2t->data_length < 0);
1731 if (conn->datadgst_en) {
1732 rc = iscsi_digest_final_send(conn, ctask, &dtask->digestbuf,
1733 &dtask->digest, 1);
1734 if (rc) {
1735 debug_tcp("send last r2t data digest 0x%x"
1736 "fail\n", dtask->digest);
1737 return rc;
1738 }
1739 debug_tcp("r2t done dout digest 0x%x\n", dtask->digest);
1740 }
1741
1742 tcp_ctask->r2t_data_count -= r2t->data_length;
1743 tcp_ctask->r2t = NULL;
1744 spin_lock_bh(&session->lock);
1745 __kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
1746 spin_unlock_bh(&session->lock);
1747 if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
1748 tcp_ctask->r2t = r2t;
1749 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1750 tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1751 return 1;
1752 }
1753
1754 return 0;
1755 }
1756
1757 static inline int
1758 handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1759 {
1760 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1761 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1762 struct iscsi_data_task *dtask = tcp_ctask->dtask;
1763 int sent = 0, rc;
1764
1765 tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
1766 iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
1767 tcp_ctask->pad_count);
1768 rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
1769 &sent);
1770 if (rc) {
1771 tcp_ctask->xmstate |= XMSTATE_W_PAD;
1772 return rc;
1773 }
1774
1775 if (conn->datadgst_en) {
1776 crypto_hash_update(&tcp_conn->data_tx_hash,
1777 &tcp_ctask->sendbuf.sg,
1778 tcp_ctask->sendbuf.sg.length);
1779 /* imm data? */
1780 if (!dtask) {
1781 rc = iscsi_digest_final_send(conn, ctask,
1782 &tcp_ctask->immbuf,
1783 &tcp_ctask->immdigest, 1);
1784 if (rc) {
1785 debug_tcp("send padding digest 0x%x"
1786 "fail!\n", tcp_ctask->immdigest);
1787 return rc;
1788 }
1789 debug_tcp("done with padding, digest 0x%x\n",
1790 tcp_ctask->datadigest);
1791 } else {
1792 rc = iscsi_digest_final_send(conn, ctask,
1793 &dtask->digestbuf,
1794 &dtask->digest, 1);
1795 if (rc) {
1796 debug_tcp("send padding digest 0x%x"
1797 "fail\n", dtask->digest);
1798 return rc;
1799 }
1800 debug_tcp("done with padding, digest 0x%x\n",
1801 dtask->digest);
1802 }
1803 }
1804
1805 return 0;
1806 }
1807
1808 static int
1809 iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1810 {
1811 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1812 int rc = 0;
1813
1814 debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
1815 conn->id, tcp_ctask->xmstate, ctask->itt);
1816
1817 /*
1818 * serialize with TMF AbortTask
1819 */
1820 if (ctask->mtask)
1821 return rc;
1822
1823 if (tcp_ctask->xmstate & XMSTATE_R_HDR)
1824 return handle_xmstate_r_hdr(conn, tcp_ctask);
1825
1826 if (tcp_ctask->xmstate & XMSTATE_W_HDR) {
1827 rc = handle_xmstate_w_hdr(conn, ctask);
1828 if (rc)
1829 return rc;
1830 }
1831
1832 /* XXX: for data digest xmit recover */
1833 if (tcp_ctask->xmstate & XMSTATE_DATA_DIGEST) {
1834 rc = handle_xmstate_data_digest(conn, ctask);
1835 if (rc)
1836 return rc;
1837 }
1838
1839 if (tcp_ctask->xmstate & XMSTATE_IMM_DATA) {
1840 rc = handle_xmstate_imm_data(conn, ctask);
1841 if (rc)
1842 return rc;
1843 }
1844
1845 if (tcp_ctask->xmstate & XMSTATE_UNS_HDR) {
1846 BUG_ON(!ctask->unsol_count);
1847 tcp_ctask->xmstate &= ~XMSTATE_UNS_HDR;
1848 unsolicit_head_again:
1849 rc = handle_xmstate_uns_hdr(conn, ctask);
1850 if (rc)
1851 return rc;
1852 }
1853
1854 if (tcp_ctask->xmstate & XMSTATE_UNS_DATA) {
1855 rc = handle_xmstate_uns_data(conn, ctask);
1856 if (rc == 1)
1857 goto unsolicit_head_again;
1858 else if (rc)
1859 return rc;
1860 goto done;
1861 }
1862
1863 if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
1864 struct iscsi_r2t_info *r2t;
1865
1866 tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1867 tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1868 if (!tcp_ctask->r2t)
1869 __kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
1870 sizeof(void*));
1871 solicit_head_again:
1872 r2t = tcp_ctask->r2t;
1873 if (conn->hdrdgst_en)
1874 iscsi_hdr_digest(conn, &r2t->headbuf,
1875 (u8*)r2t->dtask.hdrext);
1876 rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
1877 if (rc) {
1878 tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
1879 tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
1880 return rc;
1881 }
1882
1883 debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
1884 r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
1885 r2t->sent);
1886 }
1887
1888 if (tcp_ctask->xmstate & XMSTATE_SOL_DATA) {
1889 rc = handle_xmstate_sol_data(conn, ctask);
1890 if (rc == 1)
1891 goto solicit_head_again;
1892 if (rc)
1893 return rc;
1894 }
1895
1896 done:
1897 /*
1898 * Last thing to check is whether we need to send write
1899 * padding. Note that we check for xmstate equality, not just the bit.
1900 */
1901 if (tcp_ctask->xmstate == XMSTATE_W_PAD)
1902 rc = handle_xmstate_w_pad(conn, ctask);
1903
1904 return rc;
1905 }
1906
1907 static struct iscsi_cls_conn *
1908 iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1909 {
1910 struct iscsi_conn *conn;
1911 struct iscsi_cls_conn *cls_conn;
1912 struct iscsi_tcp_conn *tcp_conn;
1913
1914 cls_conn = iscsi_conn_setup(cls_session, conn_idx);
1915 if (!cls_conn)
1916 return NULL;
1917 conn = cls_conn->dd_data;
1918 /*
1919 * due to strange issues with iser these are not set
1920 * in iscsi_conn_setup
1921 */
1922 conn->max_recv_dlength = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
1923
1924 tcp_conn = kzalloc(sizeof(*tcp_conn), GFP_KERNEL);
1925 if (!tcp_conn)
1926 goto tcp_conn_alloc_fail;
1927
1928 conn->dd_data = tcp_conn;
1929 tcp_conn->iscsi_conn = conn;
1930 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
1931 /* initial operational parameters */
1932 tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
1933
1934 return cls_conn;
1935
1936 tcp_conn_alloc_fail:
1937 iscsi_conn_teardown(cls_conn);
1938 return NULL;
1939 }
1940
1941 static void
1942 iscsi_tcp_release_conn(struct iscsi_conn *conn)
1943 {
1944 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1945
1946 if (!tcp_conn->sock)
1947 return;
1948
1949 sock_hold(tcp_conn->sock->sk);
1950 iscsi_conn_restore_callbacks(tcp_conn);
1951 sock_put(tcp_conn->sock->sk);
1952
1953 sock_release(tcp_conn->sock);
1954 tcp_conn->sock = NULL;
1955 conn->recv_lock = NULL;
1956 }
1957
1958 static void
1959 iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
1960 {
1961 struct iscsi_conn *conn = cls_conn->dd_data;
1962 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1963 int digest = 0;
1964
1965 if (conn->hdrdgst_en || conn->datadgst_en)
1966 digest = 1;
1967
1968 iscsi_tcp_release_conn(conn);
1969 iscsi_conn_teardown(cls_conn);
1970
1971 /* now free tcp_conn */
1972 if (digest) {
1973 if (tcp_conn->tx_tfm)
1974 crypto_free_hash(tcp_conn->tx_tfm);
1975 if (tcp_conn->rx_tfm)
1976 crypto_free_hash(tcp_conn->rx_tfm);
1977 if (tcp_conn->data_tx_hash.tfm)
1978 crypto_free_hash(tcp_conn->data_tx_hash.tfm);
1979 if (tcp_conn->data_rx_hash.tfm)
1980 crypto_free_hash(tcp_conn->data_rx_hash.tfm);
1981 }
1982
1983 kfree(tcp_conn);
1984 }
1985
1986 static void
1987 iscsi_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1988 {
1989 struct iscsi_conn *conn = cls_conn->dd_data;
1990
1991 iscsi_conn_stop(cls_conn, flag);
1992 iscsi_tcp_release_conn(conn);
1993 }
1994
1995 static int
1996 iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
1997 struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
1998 int is_leading)
1999 {
2000 struct iscsi_conn *conn = cls_conn->dd_data;
2001 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2002 struct sock *sk;
2003 struct socket *sock;
2004 int err;
2005
2006 /* lookup for existing socket */
2007 sock = sockfd_lookup((int)transport_eph, &err);
2008 if (!sock) {
2009 printk(KERN_ERR "iscsi_tcp: sockfd_lookup failed %d\n", err);
2010 return -EEXIST;
2011 }
2012
2013 err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
2014 if (err)
2015 return err;
2016
2017 /* bind iSCSI connection and socket */
2018 tcp_conn->sock = sock;
2019
2020 /* setup Socket parameters */
2021 sk = sock->sk;
2022 sk->sk_reuse = 1;
2023 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
2024 sk->sk_allocation = GFP_ATOMIC;
2025
2026 /* FIXME: disable Nagle's algorithm */
2027
2028 /*
2029 * Intercept TCP callbacks for sendfile like receive
2030 * processing.
2031 */
2032 conn->recv_lock = &sk->sk_callback_lock;
2033 iscsi_conn_set_callbacks(conn);
2034 tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
2035 /*
2036 * set receive state machine into initial state
2037 */
2038 tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
2039
2040 return 0;
2041 }
2042
2043 /* called with host lock */
2044 static void
2045 iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask,
2046 char *data, uint32_t data_size)
2047 {
2048 struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
2049
2050 iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
2051 sizeof(struct iscsi_hdr));
2052 tcp_mtask->xmstate = XMSTATE_IMM_HDR;
2053 tcp_mtask->sent = 0;
2054
2055 if (mtask->data_count)
2056 iscsi_buf_init_iov(&tcp_mtask->sendbuf, (char*)mtask->data,
2057 mtask->data_count);
2058 }
2059
2060 static int
2061 iscsi_r2tpool_alloc(struct iscsi_session *session)
2062 {
2063 int i;
2064 int cmd_i;
2065
2066 /*
2067 * initialize per-task: R2T pool and xmit queue
2068 */
2069 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2070 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
2071 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2072
2073 /*
2074 * pre-allocated x4 as much r2ts to handle race when
2075 * target acks DataOut faster than we data_xmit() queues
2076 * could replenish r2tqueue.
2077 */
2078
2079 /* R2T pool */
2080 if (iscsi_pool_init(&tcp_ctask->r2tpool, session->max_r2t * 4,
2081 (void***)&tcp_ctask->r2ts,
2082 sizeof(struct iscsi_r2t_info))) {
2083 goto r2t_alloc_fail;
2084 }
2085
2086 /* R2T xmit queue */
2087 tcp_ctask->r2tqueue = kfifo_alloc(
2088 session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
2089 if (tcp_ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
2090 iscsi_pool_free(&tcp_ctask->r2tpool,
2091 (void**)tcp_ctask->r2ts);
2092 goto r2t_alloc_fail;
2093 }
2094 }
2095
2096 return 0;
2097
2098 r2t_alloc_fail:
2099 for (i = 0; i < cmd_i; i++) {
2100 struct iscsi_cmd_task *ctask = session->cmds[i];
2101 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2102
2103 kfifo_free(tcp_ctask->r2tqueue);
2104 iscsi_pool_free(&tcp_ctask->r2tpool,
2105 (void**)tcp_ctask->r2ts);
2106 }
2107 return -ENOMEM;
2108 }
2109
2110 static void
2111 iscsi_r2tpool_free(struct iscsi_session *session)
2112 {
2113 int i;
2114
2115 for (i = 0; i < session->cmds_max; i++) {
2116 struct iscsi_cmd_task *ctask = session->cmds[i];
2117 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2118
2119 kfifo_free(tcp_ctask->r2tqueue);
2120 iscsi_pool_free(&tcp_ctask->r2tpool,
2121 (void**)tcp_ctask->r2ts);
2122 }
2123 }
2124
2125 static int
2126 iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
2127 char *buf, int buflen)
2128 {
2129 struct iscsi_conn *conn = cls_conn->dd_data;
2130 struct iscsi_session *session = conn->session;
2131 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2132 int value;
2133
2134 switch(param) {
2135 case ISCSI_PARAM_HDRDGST_EN:
2136 iscsi_set_param(cls_conn, param, buf, buflen);
2137 tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
2138 if (conn->hdrdgst_en) {
2139 tcp_conn->hdr_size += sizeof(__u32);
2140 if (!tcp_conn->tx_tfm)
2141 tcp_conn->tx_tfm =
2142 crypto_alloc_hash("crc32c", 0,
2143 CRYPTO_ALG_ASYNC);
2144 if (IS_ERR(tcp_conn->tx_tfm))
2145 return PTR_ERR(tcp_conn->tx_tfm);
2146 if (!tcp_conn->rx_tfm)
2147 tcp_conn->rx_tfm =
2148 crypto_alloc_hash("crc32c", 0,
2149 CRYPTO_ALG_ASYNC);
2150 if (IS_ERR(tcp_conn->rx_tfm)) {
2151 crypto_free_hash(tcp_conn->tx_tfm);
2152 return PTR_ERR(tcp_conn->rx_tfm);
2153 }
2154 } else {
2155 if (tcp_conn->tx_tfm)
2156 crypto_free_hash(tcp_conn->tx_tfm);
2157 if (tcp_conn->rx_tfm)
2158 crypto_free_hash(tcp_conn->rx_tfm);
2159 }
2160 break;
2161 case ISCSI_PARAM_DATADGST_EN:
2162 iscsi_set_param(cls_conn, param, buf, buflen);
2163 if (conn->datadgst_en) {
2164 if (!tcp_conn->data_tx_hash.tfm)
2165 tcp_conn->data_tx_hash.tfm =
2166 crypto_alloc_hash("crc32c", 0,
2167 CRYPTO_ALG_ASYNC);
2168 if (IS_ERR(tcp_conn->data_tx_hash.tfm))
2169 return PTR_ERR(tcp_conn->data_tx_hash.tfm);
2170 if (!tcp_conn->data_rx_hash.tfm)
2171 tcp_conn->data_rx_hash.tfm =
2172 crypto_alloc_hash("crc32c", 0,
2173 CRYPTO_ALG_ASYNC);
2174 if (IS_ERR(tcp_conn->data_rx_hash.tfm)) {
2175 crypto_free_hash(tcp_conn->data_tx_hash.tfm);
2176 return PTR_ERR(tcp_conn->data_rx_hash.tfm);
2177 }
2178 } else {
2179 if (tcp_conn->data_tx_hash.tfm)
2180 crypto_free_hash(tcp_conn->data_tx_hash.tfm);
2181 if (tcp_conn->data_rx_hash.tfm)
2182 crypto_free_hash(tcp_conn->data_rx_hash.tfm);
2183 }
2184 tcp_conn->sendpage = conn->datadgst_en ?
2185 sock_no_sendpage : tcp_conn->sock->ops->sendpage;
2186 break;
2187 case ISCSI_PARAM_MAX_R2T:
2188 sscanf(buf, "%d", &value);
2189 if (session->max_r2t == roundup_pow_of_two(value))
2190 break;
2191 iscsi_r2tpool_free(session);
2192 iscsi_set_param(cls_conn, param, buf, buflen);
2193 if (session->max_r2t & (session->max_r2t - 1))
2194 session->max_r2t = roundup_pow_of_two(session->max_r2t);
2195 if (iscsi_r2tpool_alloc(session))
2196 return -ENOMEM;
2197 break;
2198 default:
2199 return iscsi_set_param(cls_conn, param, buf, buflen);
2200 }
2201
2202 return 0;
2203 }
2204
2205 static int
2206 iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
2207 enum iscsi_param param, char *buf)
2208 {
2209 struct iscsi_conn *conn = cls_conn->dd_data;
2210 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2211 struct inet_sock *inet;
2212 struct ipv6_pinfo *np;
2213 struct sock *sk;
2214 int len;
2215
2216 switch(param) {
2217 case ISCSI_PARAM_CONN_PORT:
2218 mutex_lock(&conn->xmitmutex);
2219 if (!tcp_conn->sock) {
2220 mutex_unlock(&conn->xmitmutex);
2221 return -EINVAL;
2222 }
2223
2224 inet = inet_sk(tcp_conn->sock->sk);
2225 len = sprintf(buf, "%hu\n", be16_to_cpu(inet->dport));
2226 mutex_unlock(&conn->xmitmutex);
2227 break;
2228 case ISCSI_PARAM_CONN_ADDRESS:
2229 mutex_lock(&conn->xmitmutex);
2230 if (!tcp_conn->sock) {
2231 mutex_unlock(&conn->xmitmutex);
2232 return -EINVAL;
2233 }
2234
2235 sk = tcp_conn->sock->sk;
2236 if (sk->sk_family == PF_INET) {
2237 inet = inet_sk(sk);
2238 len = sprintf(buf, "%u.%u.%u.%u\n",
2239 NIPQUAD(inet->daddr));
2240 } else {
2241 np = inet6_sk(sk);
2242 len = sprintf(buf,
2243 "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
2244 NIP6(np->daddr));
2245 }
2246 mutex_unlock(&conn->xmitmutex);
2247 break;
2248 default:
2249 return iscsi_conn_get_param(cls_conn, param, buf);
2250 }
2251
2252 return len;
2253 }
2254
2255 static void
2256 iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
2257 {
2258 struct iscsi_conn *conn = cls_conn->dd_data;
2259 struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2260
2261 stats->txdata_octets = conn->txdata_octets;
2262 stats->rxdata_octets = conn->rxdata_octets;
2263 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
2264 stats->dataout_pdus = conn->dataout_pdus_cnt;
2265 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
2266 stats->datain_pdus = conn->datain_pdus_cnt;
2267 stats->r2t_pdus = conn->r2t_pdus_cnt;
2268 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
2269 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
2270 stats->custom_length = 3;
2271 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
2272 stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
2273 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
2274 stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
2275 strcpy(stats->custom[2].desc, "eh_abort_cnt");
2276 stats->custom[2].value = conn->eh_abort_cnt;
2277 }
2278
2279 static struct iscsi_cls_session *
2280 iscsi_tcp_session_create(struct iscsi_transport *iscsit,
2281 struct scsi_transport_template *scsit,
2282 uint32_t initial_cmdsn, uint32_t *hostno)
2283 {
2284 struct iscsi_cls_session *cls_session;
2285 struct iscsi_session *session;
2286 uint32_t hn;
2287 int cmd_i;
2288
2289 cls_session = iscsi_session_setup(iscsit, scsit,
2290 sizeof(struct iscsi_tcp_cmd_task),
2291 sizeof(struct iscsi_tcp_mgmt_task),
2292 initial_cmdsn, &hn);
2293 if (!cls_session)
2294 return NULL;
2295 *hostno = hn;
2296
2297 session = class_to_transport_session(cls_session);
2298 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2299 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
2300 struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2301
2302 ctask->hdr = &tcp_ctask->hdr;
2303 }
2304
2305 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
2306 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
2307 struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
2308
2309 mtask->hdr = &tcp_mtask->hdr;
2310 }
2311
2312 if (iscsi_r2tpool_alloc(class_to_transport_session(cls_session)))
2313 goto r2tpool_alloc_fail;
2314
2315 return cls_session;
2316
2317 r2tpool_alloc_fail:
2318 iscsi_session_teardown(cls_session);
2319 return NULL;
2320 }
2321
2322 static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
2323 {
2324 iscsi_r2tpool_free(class_to_transport_session(cls_session));
2325 iscsi_session_teardown(cls_session);
2326 }
2327
2328 static struct scsi_host_template iscsi_sht = {
2329 .name = "iSCSI Initiator over TCP/IP",
2330 .queuecommand = iscsi_queuecommand,
2331 .change_queue_depth = iscsi_change_queue_depth,
2332 .can_queue = ISCSI_XMIT_CMDS_MAX - 1,
2333 .sg_tablesize = ISCSI_SG_TABLESIZE,
2334 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
2335 .eh_abort_handler = iscsi_eh_abort,
2336 .eh_host_reset_handler = iscsi_eh_host_reset,
2337 .use_clustering = DISABLE_CLUSTERING,
2338 .proc_name = "iscsi_tcp",
2339 .this_id = -1,
2340 };
2341
2342 static struct iscsi_transport iscsi_tcp_transport = {
2343 .owner = THIS_MODULE,
2344 .name = "tcp",
2345 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
2346 | CAP_DATADGST,
2347 .param_mask = ISCSI_MAX_RECV_DLENGTH |
2348 ISCSI_MAX_XMIT_DLENGTH |
2349 ISCSI_HDRDGST_EN |
2350 ISCSI_DATADGST_EN |
2351 ISCSI_INITIAL_R2T_EN |
2352 ISCSI_MAX_R2T |
2353 ISCSI_IMM_DATA_EN |
2354 ISCSI_FIRST_BURST |
2355 ISCSI_MAX_BURST |
2356 ISCSI_PDU_INORDER_EN |
2357 ISCSI_DATASEQ_INORDER_EN |
2358 ISCSI_ERL |
2359 ISCSI_CONN_PORT |
2360 ISCSI_CONN_ADDRESS |
2361 ISCSI_EXP_STATSN |
2362 ISCSI_PERSISTENT_PORT |
2363 ISCSI_PERSISTENT_ADDRESS |
2364 ISCSI_TARGET_NAME |
2365 ISCSI_TPGT,
2366 .host_template = &iscsi_sht,
2367 .conndata_size = sizeof(struct iscsi_conn),
2368 .max_conn = 1,
2369 .max_cmd_len = ISCSI_TCP_MAX_CMD_LEN,
2370 /* session management */
2371 .create_session = iscsi_tcp_session_create,
2372 .destroy_session = iscsi_tcp_session_destroy,
2373 /* connection management */
2374 .create_conn = iscsi_tcp_conn_create,
2375 .bind_conn = iscsi_tcp_conn_bind,
2376 .destroy_conn = iscsi_tcp_conn_destroy,
2377 .set_param = iscsi_conn_set_param,
2378 .get_conn_param = iscsi_tcp_conn_get_param,
2379 .get_session_param = iscsi_session_get_param,
2380 .start_conn = iscsi_conn_start,
2381 .stop_conn = iscsi_tcp_conn_stop,
2382 /* IO */
2383 .send_pdu = iscsi_conn_send_pdu,
2384 .get_stats = iscsi_conn_get_stats,
2385 .init_cmd_task = iscsi_tcp_cmd_init,
2386 .init_mgmt_task = iscsi_tcp_mgmt_init,
2387 .xmit_cmd_task = iscsi_tcp_ctask_xmit,
2388 .xmit_mgmt_task = iscsi_tcp_mtask_xmit,
2389 .cleanup_cmd_task = iscsi_tcp_cleanup_ctask,
2390 /* recovery */
2391 .session_recovery_timedout = iscsi_session_recovery_timedout,
2392 };
2393
2394 static int __init
2395 iscsi_tcp_init(void)
2396 {
2397 if (iscsi_max_lun < 1) {
2398 printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
2399 iscsi_max_lun);
2400 return -EINVAL;
2401 }
2402 iscsi_tcp_transport.max_lun = iscsi_max_lun;
2403
2404 if (!iscsi_register_transport(&iscsi_tcp_transport))
2405 return -ENODEV;
2406
2407 return 0;
2408 }
2409
2410 static void __exit
2411 iscsi_tcp_exit(void)
2412 {
2413 iscsi_unregister_transport(&iscsi_tcp_transport);
2414 }
2415
2416 module_init(iscsi_tcp_init);
2417 module_exit(iscsi_tcp_exit);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree