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[SCSI] iscsi: lower queue depth
[usb.git] / drivers / scsi / iscsi_tcp.c
blob5b14c404069f13d40a2f3b28a17855311c7827db
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 Mike Christie
7 * maintained by open-iscsi@googlegroups.com
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published
11 * by the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * See the file COPYING included with this distribution for more details.
20 *
21 * Credits:
22 * Christoph Hellwig
23 * FUJITA Tomonori
24 * Arne Redlich
25 * Zhenyu Wang
26 */
27
28 #include <linux/types.h>
29 #include <linux/list.h>
30 #include <linux/inet.h>
31 #include <linux/blkdev.h>
32 #include <linux/crypto.h>
33 #include <linux/delay.h>
34 #include <linux/kfifo.h>
35 #include <linux/scatterlist.h>
36 #include <net/tcp.h>
37 #include <scsi/scsi_cmnd.h>
38 #include <scsi/scsi_device.h>
39 #include <scsi/scsi_eh.h>
40 #include <scsi/scsi_request.h>
41 #include <scsi/scsi_tcq.h>
42 #include <scsi/scsi_host.h>
43 #include <scsi/scsi.h>
44 #include <scsi/scsi_transport_iscsi.h>
45
46 #include "iscsi_tcp.h"
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("0:4.409");
53 /* #define DEBUG_TCP */
54 /* #define DEBUG_SCSI */
55 #define DEBUG_ASSERT
56
57 #ifdef DEBUG_TCP
58 #define debug_tcp(fmt...) printk(KERN_DEBUG "tcp: " fmt)
59 #else
60 #define debug_tcp(fmt...)
61 #endif
62
63 #ifdef DEBUG_SCSI
64 #define debug_scsi(fmt...) printk(KERN_DEBUG "scsi: " fmt)
65 #else
66 #define debug_scsi(fmt...)
67 #endif
68
69 #ifndef DEBUG_ASSERT
70 #ifdef BUG_ON
71 #undef BUG_ON
72 #endif
73 #define BUG_ON(expr)
74 #endif
75
76 #define INVALID_SN_DELTA 0xffff
77
78 static unsigned int iscsi_max_lun = 512;
79 module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
80
81 /* global data */
82 static kmem_cache_t *taskcache;
83
84 static inline void
85 iscsi_buf_init_virt(struct iscsi_buf *ibuf, char *vbuf, int size)
86 {
87 sg_init_one(&ibuf->sg, (u8 *)vbuf, size);
88 ibuf->sent = 0;
89 }
90
91 static inline void
92 iscsi_buf_init_iov(struct iscsi_buf *ibuf, char *vbuf, int size)
93 {
94 ibuf->sg.page = (void*)vbuf;
95 ibuf->sg.offset = (unsigned int)-1;
96 ibuf->sg.length = size;
97 ibuf->sent = 0;
98 }
99
100 static inline void*
101 iscsi_buf_iov_base(struct iscsi_buf *ibuf)
102 {
103 return (char*)ibuf->sg.page + ibuf->sent;
104 }
105
106 static inline void
107 iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
108 {
109 /*
110 * Fastpath: sg element fits into single page
111 */
112 if (sg->length + sg->offset <= PAGE_SIZE && page_count(sg->page) >= 2) {
113 ibuf->sg.page = sg->page;
114 ibuf->sg.offset = sg->offset;
115 ibuf->sg.length = sg->length;
116 } else
117 iscsi_buf_init_iov(ibuf, page_address(sg->page), sg->length);
118 ibuf->sent = 0;
119 }
120
121 static inline int
122 iscsi_buf_left(struct iscsi_buf *ibuf)
123 {
124 int rc;
125
126 rc = ibuf->sg.length - ibuf->sent;
127 BUG_ON(rc < 0);
128 return rc;
129 }
130
131 static inline void
132 iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
133 u8* crc)
134 {
135 crypto_digest_digest(conn->tx_tfm, &buf->sg, 1, crc);
136 buf->sg.length += sizeof(uint32_t);
137 }
138
139 static void
140 iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
141 {
142 struct iscsi_session *session = conn->session;
143 unsigned long flags;
144
145 spin_lock_irqsave(&session->lock, flags);
146 if (session->conn_cnt == 1 || session->leadconn == conn)
147 session->state = ISCSI_STATE_FAILED;
148 spin_unlock_irqrestore(&session->lock, flags);
149 set_bit(SUSPEND_BIT, &conn->suspend_tx);
150 set_bit(SUSPEND_BIT, &conn->suspend_rx);
151 iscsi_conn_error(iscsi_handle(conn), err);
152 }
153
154 static inline int
155 iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
156 {
157 uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
158 uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
159
160 if (max_cmdsn < exp_cmdsn -1 &&
161 max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
162 return ISCSI_ERR_MAX_CMDSN;
163 if (max_cmdsn > session->max_cmdsn ||
164 max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
165 session->max_cmdsn = max_cmdsn;
166 if (exp_cmdsn > session->exp_cmdsn ||
167 exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
168 session->exp_cmdsn = exp_cmdsn;
169
170 return 0;
171 }
172
173 static inline int
174 iscsi_hdr_extract(struct iscsi_conn *conn)
175 {
176 struct sk_buff *skb = conn->in.skb;
177
178 if (conn->in.copy >= conn->hdr_size &&
179 conn->in_progress == IN_PROGRESS_WAIT_HEADER) {
180 /*
181 * Zero-copy PDU Header: using connection context
182 * to store header pointer.
183 */
184 if (skb_shinfo(skb)->frag_list == NULL &&
185 !skb_shinfo(skb)->nr_frags)
186 conn->in.hdr = (struct iscsi_hdr *)
187 ((char*)skb->data + conn->in.offset);
188 else {
189 /* ignoring return code since we checked
190 * in.copy before */
191 skb_copy_bits(skb, conn->in.offset,
192 &conn->hdr, conn->hdr_size);
193 conn->in.hdr = &conn->hdr;
194 }
195 conn->in.offset += conn->hdr_size;
196 conn->in.copy -= conn->hdr_size;
197 } else {
198 int hdr_remains;
199 int copylen;
200
201 /*
202 * PDU header scattered across SKB's,
203 * copying it... This'll happen quite rarely.
204 */
205
206 if (conn->in_progress == IN_PROGRESS_WAIT_HEADER)
207 conn->in.hdr_offset = 0;
208
209 hdr_remains = conn->hdr_size - conn->in.hdr_offset;
210 BUG_ON(hdr_remains <= 0);
211
212 copylen = min(conn->in.copy, hdr_remains);
213 skb_copy_bits(skb, conn->in.offset,
214 (char*)&conn->hdr + conn->in.hdr_offset, copylen);
215
216 debug_tcp("PDU gather offset %d bytes %d in.offset %d "
217 "in.copy %d\n", conn->in.hdr_offset, copylen,
218 conn->in.offset, conn->in.copy);
219
220 conn->in.offset += copylen;
221 conn->in.copy -= copylen;
222 if (copylen < hdr_remains) {
223 conn->in_progress = IN_PROGRESS_HEADER_GATHER;
224 conn->in.hdr_offset += copylen;
225 return -EAGAIN;
226 }
227 conn->in.hdr = &conn->hdr;
228 conn->discontiguous_hdr_cnt++;
229 conn->in_progress = IN_PROGRESS_WAIT_HEADER;
230 }
231
232 return 0;
233 }
234
235 static inline void
236 iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
237 {
238 struct scsi_cmnd *sc = ctask->sc;
239 struct iscsi_session *session = conn->session;
240
241 spin_lock(&session->lock);
242 if (unlikely(!sc)) {
243 spin_unlock(&session->lock);
244 return;
245 }
246 if (sc->sc_data_direction == DMA_TO_DEVICE) {
247 struct iscsi_data_task *dtask, *n;
248 /* WRITE: cleanup Data-Out's if any */
249 spin_lock(&conn->lock);
250 list_for_each_entry_safe(dtask, n, &ctask->dataqueue, item) {
251 list_del(&dtask->item);
252 mempool_free(dtask, ctask->datapool);
253 }
254 spin_unlock(&conn->lock);
255 }
256 ctask->xmstate = XMSTATE_IDLE;
257 ctask->r2t = NULL;
258 ctask->sc = NULL;
259 __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
260 spin_unlock(&session->lock);
261 }
262
263 /**
264 * iscsi_cmd_rsp - SCSI Command Response processing
265 * @conn: iscsi connection
266 * @ctask: scsi command task
267 **/
268 static int
269 iscsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
270 {
271 int rc;
272 struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)conn->in.hdr;
273 struct iscsi_session *session = conn->session;
274 struct scsi_cmnd *sc = ctask->sc;
275
276 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
277 if (rc) {
278 sc->result = (DID_ERROR << 16);
279 goto out;
280 }
281
282 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
283
284 sc->result = (DID_OK << 16) | rhdr->cmd_status;
285
286 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
287 sc->result = (DID_ERROR << 16);
288 goto out;
289 }
290
291 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION && conn->senselen) {
292 int sensecopy = min(conn->senselen, SCSI_SENSE_BUFFERSIZE);
293
294 memcpy(sc->sense_buffer, conn->data + 2, sensecopy);
295 debug_scsi("copied %d bytes of sense\n", sensecopy);
296 }
297
298 if (sc->sc_data_direction == DMA_TO_DEVICE)
299 goto out;
300
301 if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
302 int res_count = be32_to_cpu(rhdr->residual_count);
303
304 if (res_count > 0 && res_count <= sc->request_bufflen)
305 sc->resid = res_count;
306 else
307 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
308 } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
309 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
310 else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
311 sc->resid = be32_to_cpu(rhdr->residual_count);
312
313 out:
314 debug_scsi("done [sc %lx res %d itt 0x%x]\n",
315 (long)sc, sc->result, ctask->itt);
316 conn->scsirsp_pdus_cnt++;
317 iscsi_ctask_cleanup(conn, ctask);
318 sc->scsi_done(sc);
319 return rc;
320 }
321
322 /**
323 * iscsi_data_rsp - SCSI Data-In Response processing
324 * @conn: iscsi connection
325 * @ctask: scsi command task
326 **/
327 static int
328 iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
329 {
330 int rc;
331 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)conn->in.hdr;
332 struct iscsi_session *session = conn->session;
333 int datasn = be32_to_cpu(rhdr->datasn);
334
335 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
336 if (rc)
337 return rc;
338 /*
339 * setup Data-In byte counter (gets decremented..)
340 */
341 ctask->data_count = conn->in.datalen;
342
343 if (conn->in.datalen == 0)
344 return 0;
345
346 if (ctask->datasn != datasn)
347 return ISCSI_ERR_DATASN;
348
349 ctask->datasn++;
350
351 ctask->data_offset = be32_to_cpu(rhdr->offset);
352 if (ctask->data_offset + conn->in.datalen > ctask->total_length)
353 return ISCSI_ERR_DATA_OFFSET;
354
355 if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
356 struct scsi_cmnd *sc = ctask->sc;
357
358 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
359 if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
360 int res_count = be32_to_cpu(rhdr->residual_count);
361
362 if (res_count > 0 &&
363 res_count <= sc->request_bufflen) {
364 sc->resid = res_count;
365 sc->result = (DID_OK << 16) | rhdr->cmd_status;
366 } else
367 sc->result = (DID_BAD_TARGET << 16) |
368 rhdr->cmd_status;
369 } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
370 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
371 else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW) {
372 sc->resid = be32_to_cpu(rhdr->residual_count);
373 sc->result = (DID_OK << 16) | rhdr->cmd_status;
374 } else
375 sc->result = (DID_OK << 16) | rhdr->cmd_status;
376 }
377
378 conn->datain_pdus_cnt++;
379 return 0;
380 }
381
382 /**
383 * iscsi_solicit_data_init - initialize first Data-Out
384 * @conn: iscsi connection
385 * @ctask: scsi command task
386 * @r2t: R2T info
387 *
388 * Notes:
389 * Initialize first Data-Out within this R2T sequence and finds
390 * proper data_offset within this SCSI command.
391 *
392 * This function is called with connection lock taken.
393 **/
394 static void
395 iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
396 struct iscsi_r2t_info *r2t)
397 {
398 struct iscsi_data *hdr;
399 struct iscsi_data_task *dtask;
400 struct scsi_cmnd *sc = ctask->sc;
401
402 dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
403 BUG_ON(!dtask);
404 hdr = &dtask->hdr;
405 memset(hdr, 0, sizeof(struct iscsi_data));
406 hdr->ttt = r2t->ttt;
407 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
408 r2t->solicit_datasn++;
409 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
410 memcpy(hdr->lun, ctask->hdr.lun, sizeof(hdr->lun));
411 hdr->itt = ctask->hdr.itt;
412 hdr->exp_statsn = r2t->exp_statsn;
413 hdr->offset = cpu_to_be32(r2t->data_offset);
414 if (r2t->data_length > conn->max_xmit_dlength) {
415 hton24(hdr->dlength, conn->max_xmit_dlength);
416 r2t->data_count = conn->max_xmit_dlength;
417 hdr->flags = 0;
418 } else {
419 hton24(hdr->dlength, r2t->data_length);
420 r2t->data_count = r2t->data_length;
421 hdr->flags = ISCSI_FLAG_CMD_FINAL;
422 }
423 conn->dataout_pdus_cnt++;
424
425 r2t->sent = 0;
426
427 iscsi_buf_init_virt(&r2t->headbuf, (char*)hdr,
428 sizeof(struct iscsi_hdr));
429
430 r2t->dtask = dtask;
431
432 if (sc->use_sg) {
433 int i, sg_count = 0;
434 struct scatterlist *sg = sc->request_buffer;
435
436 r2t->sg = NULL;
437 for (i = 0; i < sc->use_sg; i++, sg += 1) {
438 /* FIXME: prefetch ? */
439 if (sg_count + sg->length > r2t->data_offset) {
440 int page_offset;
441
442 /* sg page found! */
443
444 /* offset within this page */
445 page_offset = r2t->data_offset - sg_count;
446
447 /* fill in this buffer */
448 iscsi_buf_init_sg(&r2t->sendbuf, sg);
449 r2t->sendbuf.sg.offset += page_offset;
450 r2t->sendbuf.sg.length -= page_offset;
451
452 /* xmit logic will continue with next one */
453 r2t->sg = sg + 1;
454 break;
455 }
456 sg_count += sg->length;
457 }
458 BUG_ON(r2t->sg == NULL);
459 } else
460 iscsi_buf_init_iov(&ctask->sendbuf,
461 (char*)sc->request_buffer + r2t->data_offset,
462 r2t->data_count);
463
464 list_add(&dtask->item, &ctask->dataqueue);
465 }
466
467 /**
468 * iscsi_r2t_rsp - iSCSI R2T Response processing
469 * @conn: iscsi connection
470 * @ctask: scsi command task
471 **/
472 static int
473 iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
474 {
475 struct iscsi_r2t_info *r2t;
476 struct iscsi_session *session = conn->session;
477 struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)conn->in.hdr;
478 int r2tsn = be32_to_cpu(rhdr->r2tsn);
479 int rc;
480
481 if (conn->in.ahslen)
482 return ISCSI_ERR_AHSLEN;
483
484 if (conn->in.datalen)
485 return ISCSI_ERR_DATALEN;
486
487 if (ctask->exp_r2tsn && ctask->exp_r2tsn != r2tsn)
488 return ISCSI_ERR_R2TSN;
489
490 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
491 if (rc)
492 return rc;
493
494 /* FIXME: use R2TSN to detect missing R2T */
495
496 /* fill-in new R2T associated with the task */
497 spin_lock(&session->lock);
498 if (!ctask->sc || ctask->mtask ||
499 session->state != ISCSI_STATE_LOGGED_IN) {
500 printk(KERN_INFO "iscsi_tcp: dropping R2T itt %d in "
501 "recovery...\n", ctask->itt);
502 spin_unlock(&session->lock);
503 return 0;
504 }
505 rc = __kfifo_get(ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
506 BUG_ON(!rc);
507
508 r2t->exp_statsn = rhdr->statsn;
509 r2t->data_length = be32_to_cpu(rhdr->data_length);
510 if (r2t->data_length == 0 ||
511 r2t->data_length > session->max_burst) {
512 spin_unlock(&session->lock);
513 return ISCSI_ERR_DATALEN;
514 }
515
516 r2t->data_offset = be32_to_cpu(rhdr->data_offset);
517 if (r2t->data_offset + r2t->data_length > ctask->total_length) {
518 spin_unlock(&session->lock);
519 return ISCSI_ERR_DATALEN;
520 }
521
522 r2t->ttt = rhdr->ttt; /* no flip */
523 r2t->solicit_datasn = 0;
524
525 iscsi_solicit_data_init(conn, ctask, r2t);
526
527 ctask->exp_r2tsn = r2tsn + 1;
528 ctask->xmstate |= XMSTATE_SOL_HDR;
529 __kfifo_put(ctask->r2tqueue, (void*)&r2t, sizeof(void*));
530 __kfifo_put(conn->writequeue, (void*)&ctask, sizeof(void*));
531
532 schedule_work(&conn->xmitwork);
533 conn->r2t_pdus_cnt++;
534 spin_unlock(&session->lock);
535
536 return 0;
537 }
538
539 static int
540 iscsi_hdr_recv(struct iscsi_conn *conn)
541 {
542 int rc = 0;
543 struct iscsi_hdr *hdr;
544 struct iscsi_cmd_task *ctask;
545 struct iscsi_session *session = conn->session;
546 uint32_t cdgst, rdgst = 0;
547
548 hdr = conn->in.hdr;
549
550 /* verify PDU length */
551 conn->in.datalen = ntoh24(hdr->dlength);
552 if (conn->in.datalen > conn->max_recv_dlength) {
553 printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
554 conn->in.datalen, conn->max_recv_dlength);
555 return ISCSI_ERR_DATALEN;
556 }
557 conn->data_copied = 0;
558
559 /* read AHS */
560 conn->in.ahslen = hdr->hlength * 4;
561 conn->in.offset += conn->in.ahslen;
562 conn->in.copy -= conn->in.ahslen;
563 if (conn->in.copy < 0) {
564 printk(KERN_ERR "iscsi_tcp: can't handle AHS with length "
565 "%d bytes\n", conn->in.ahslen);
566 return ISCSI_ERR_AHSLEN;
567 }
568
569 /* calculate read padding */
570 conn->in.padding = conn->in.datalen & (ISCSI_PAD_LEN-1);
571 if (conn->in.padding) {
572 conn->in.padding = ISCSI_PAD_LEN - conn->in.padding;
573 debug_scsi("read padding %d bytes\n", conn->in.padding);
574 }
575
576 if (conn->hdrdgst_en) {
577 struct scatterlist sg;
578
579 sg_init_one(&sg, (u8 *)hdr,
580 sizeof(struct iscsi_hdr) + conn->in.ahslen);
581 crypto_digest_digest(conn->rx_tfm, &sg, 1, (u8 *)&cdgst);
582 rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
583 conn->in.ahslen);
584 }
585
586 /* save opcode for later */
587 conn->in.opcode = hdr->opcode & ISCSI_OPCODE_MASK;
588
589 /* verify itt (itt encoding: age+cid+itt) */
590 if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
591 if ((hdr->itt & AGE_MASK) !=
592 (session->age << AGE_SHIFT)) {
593 printk(KERN_ERR "iscsi_tcp: received itt %x expected "
594 "session age (%x)\n", hdr->itt,
595 session->age & AGE_MASK);
596 return ISCSI_ERR_BAD_ITT;
597 }
598
599 if ((hdr->itt & CID_MASK) != (conn->id << CID_SHIFT)) {
600 printk(KERN_ERR "iscsi_tcp: received itt %x, expected "
601 "CID (%x)\n", hdr->itt, conn->id);
602 return ISCSI_ERR_BAD_ITT;
603 }
604 conn->in.itt = hdr->itt & ITT_MASK;
605 } else
606 conn->in.itt = hdr->itt;
607
608 debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
609 hdr->opcode, conn->in.offset, conn->in.copy,
610 conn->in.ahslen, conn->in.datalen);
611
612 if (conn->in.itt < session->cmds_max) {
613 if (conn->hdrdgst_en && cdgst != rdgst) {
614 printk(KERN_ERR "iscsi_tcp: itt %x: hdrdgst error "
615 "recv 0x%x calc 0x%x\n", conn->in.itt, rdgst,
616 cdgst);
617 return ISCSI_ERR_HDR_DGST;
618 }
619
620 ctask = (struct iscsi_cmd_task *)session->cmds[conn->in.itt];
621
622 if (!ctask->sc) {
623 printk(KERN_INFO "iscsi_tcp: dropping ctask with "
624 "itt 0x%x\n", ctask->itt);
625 conn->in.datalen = 0; /* force drop */
626 return 0;
627 }
628
629 if (ctask->sc->SCp.phase != session->age) {
630 printk(KERN_ERR "iscsi_tcp: ctask's session age %d, "
631 "expected %d\n", ctask->sc->SCp.phase,
632 session->age);
633 return ISCSI_ERR_SESSION_FAILED;
634 }
635
636 conn->in.ctask = ctask;
637
638 debug_scsi("rsp [op 0x%x cid %d sc %lx itt 0x%x len %d]\n",
639 hdr->opcode, conn->id, (long)ctask->sc,
640 ctask->itt, conn->in.datalen);
641
642 switch(conn->in.opcode) {
643 case ISCSI_OP_SCSI_CMD_RSP:
644 BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
645 if (!conn->in.datalen)
646 rc = iscsi_cmd_rsp(conn, ctask);
647 else
648 /*
649 * got sense or response data; copying PDU
650 * Header to the connection's header
651 * placeholder
652 */
653 memcpy(&conn->hdr, hdr,
654 sizeof(struct iscsi_hdr));
655 break;
656 case ISCSI_OP_SCSI_DATA_IN:
657 BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
658 /* save flags for non-exceptional status */
659 conn->in.flags = hdr->flags;
660 /* save cmd_status for sense data */
661 conn->in.cmd_status =
662 ((struct iscsi_data_rsp*)hdr)->cmd_status;
663 rc = iscsi_data_rsp(conn, ctask);
664 break;
665 case ISCSI_OP_R2T:
666 BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
667 if (ctask->sc->sc_data_direction == DMA_TO_DEVICE)
668 rc = iscsi_r2t_rsp(conn, ctask);
669 else
670 rc = ISCSI_ERR_PROTO;
671 break;
672 default:
673 rc = ISCSI_ERR_BAD_OPCODE;
674 break;
675 }
676 } else if (conn->in.itt >= ISCSI_MGMT_ITT_OFFSET &&
677 conn->in.itt < ISCSI_MGMT_ITT_OFFSET +
678 session->mgmtpool_max) {
679 struct iscsi_mgmt_task *mtask = (struct iscsi_mgmt_task *)
680 session->mgmt_cmds[conn->in.itt -
681 ISCSI_MGMT_ITT_OFFSET];
682
683 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
684 conn->in.opcode, conn->id, mtask->itt,
685 conn->in.datalen);
686
687 switch(conn->in.opcode) {
688 case ISCSI_OP_LOGIN_RSP:
689 case ISCSI_OP_TEXT_RSP:
690 case ISCSI_OP_LOGOUT_RSP:
691 rc = iscsi_check_assign_cmdsn(session,
692 (struct iscsi_nopin*)hdr);
693 if (rc)
694 break;
695
696 if (!conn->in.datalen) {
697 rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
698 NULL, 0);
699 if (conn->login_mtask != mtask) {
700 spin_lock(&session->lock);
701 __kfifo_put(session->mgmtpool.queue,
702 (void*)&mtask, sizeof(void*));
703 spin_unlock(&session->lock);
704 }
705 }
706 break;
707 case ISCSI_OP_SCSI_TMFUNC_RSP:
708 rc = iscsi_check_assign_cmdsn(session,
709 (struct iscsi_nopin*)hdr);
710 if (rc)
711 break;
712
713 if (conn->in.datalen || conn->in.ahslen) {
714 rc = ISCSI_ERR_PROTO;
715 break;
716 }
717 conn->tmfrsp_pdus_cnt++;
718 spin_lock(&session->lock);
719 if (conn->tmabort_state == TMABORT_INITIAL) {
720 __kfifo_put(session->mgmtpool.queue,
721 (void*)&mtask, sizeof(void*));
722 conn->tmabort_state =
723 ((struct iscsi_tm_rsp *)hdr)->
724 response == ISCSI_TMF_RSP_COMPLETE ?
725 TMABORT_SUCCESS:TMABORT_FAILED;
726 /* unblock eh_abort() */
727 wake_up(&conn->ehwait);
728 }
729 spin_unlock(&session->lock);
730 break;
731 case ISCSI_OP_NOOP_IN:
732 if (hdr->ttt != ISCSI_RESERVED_TAG) {
733 rc = ISCSI_ERR_PROTO;
734 break;
735 }
736 rc = iscsi_check_assign_cmdsn(session,
737 (struct iscsi_nopin*)hdr);
738 if (rc)
739 break;
740 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
741
742 if (!conn->in.datalen) {
743 struct iscsi_mgmt_task *mtask;
744
745 rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
746 NULL, 0);
747 mtask = (struct iscsi_mgmt_task *)
748 session->mgmt_cmds[conn->in.itt -
749 ISCSI_MGMT_ITT_OFFSET];
750 if (conn->login_mtask != mtask) {
751 spin_lock(&session->lock);
752 __kfifo_put(session->mgmtpool.queue,
753 (void*)&mtask, sizeof(void*));
754 spin_unlock(&session->lock);
755 }
756 }
757 break;
758 default:
759 rc = ISCSI_ERR_BAD_OPCODE;
760 break;
761 }
762 } else if (conn->in.itt == ISCSI_RESERVED_TAG) {
763 switch(conn->in.opcode) {
764 case ISCSI_OP_NOOP_IN:
765 if (!conn->in.datalen) {
766 rc = iscsi_check_assign_cmdsn(session,
767 (struct iscsi_nopin*)hdr);
768 if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
769 rc = iscsi_recv_pdu(iscsi_handle(conn),
770 hdr, NULL, 0);
771 } else
772 rc = ISCSI_ERR_PROTO;
773 break;
774 case ISCSI_OP_REJECT:
775 /* we need sth like iscsi_reject_rsp()*/
776 case ISCSI_OP_ASYNC_EVENT:
777 /* we need sth like iscsi_async_event_rsp() */
778 rc = ISCSI_ERR_BAD_OPCODE;
779 break;
780 default:
781 rc = ISCSI_ERR_BAD_OPCODE;
782 break;
783 }
784 } else
785 rc = ISCSI_ERR_BAD_ITT;
786
787 return rc;
788 }
789
790 /**
791 * iscsi_ctask_copy - copy skb bits to the destanation cmd task
792 * @conn: iscsi connection
793 * @ctask: scsi command task
794 * @buf: buffer to copy to
795 * @buf_size: size of buffer
796 * @offset: offset within the buffer
797 *
798 * Notes:
799 * The function calls skb_copy_bits() and updates per-connection and
800 * per-cmd byte counters.
801 *
802 * Read counters (in bytes):
803 *
804 * conn->in.offset offset within in progress SKB
805 * conn->in.copy left to copy from in progress SKB
806 * including padding
807 * conn->in.copied copied already from in progress SKB
808 * conn->data_copied copied already from in progress buffer
809 * ctask->sent total bytes sent up to the MidLayer
810 * ctask->data_count left to copy from in progress Data-In
811 * buf_left left to copy from in progress buffer
812 **/
813 static inline int
814 iscsi_ctask_copy(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
815 void *buf, int buf_size, int offset)
816 {
817 int buf_left = buf_size - (conn->data_copied + offset);
818 int size = min(conn->in.copy, buf_left);
819 int rc;
820
821 size = min(size, ctask->data_count);
822
823 debug_tcp("ctask_copy %d bytes at offset %d copied %d\n",
824 size, conn->in.offset, conn->in.copied);
825
826 BUG_ON(size <= 0);
827 BUG_ON(ctask->sent + size > ctask->total_length);
828
829 rc = skb_copy_bits(conn->in.skb, conn->in.offset,
830 (char*)buf + (offset + conn->data_copied), size);
831 /* must fit into skb->len */
832 BUG_ON(rc);
833
834 conn->in.offset += size;
835 conn->in.copy -= size;
836 conn->in.copied += size;
837 conn->data_copied += size;
838 ctask->sent += size;
839 ctask->data_count -= size;
840
841 BUG_ON(conn->in.copy < 0);
842 BUG_ON(ctask->data_count < 0);
843
844 if (buf_size != (conn->data_copied + offset)) {
845 if (!ctask->data_count) {
846 BUG_ON(buf_size - conn->data_copied < 0);
847 /* done with this PDU */
848 return buf_size - conn->data_copied;
849 }
850 return -EAGAIN;
851 }
852
853 /* done with this buffer or with both - PDU and buffer */
854 conn->data_copied = 0;
855 return 0;
856 }
857
858 /**
859 * iscsi_tcp_copy - copy skb bits to the destanation buffer
860 * @conn: iscsi connection
861 * @buf: buffer to copy to
862 * @buf_size: number of bytes to copy
863 *
864 * Notes:
865 * The function calls skb_copy_bits() and updates per-connection
866 * byte counters.
867 **/
868 static inline int
869 iscsi_tcp_copy(struct iscsi_conn *conn, void *buf, int buf_size)
870 {
871 int buf_left = buf_size - conn->data_copied;
872 int size = min(conn->in.copy, buf_left);
873 int rc;
874
875 debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
876 size, conn->in.offset, conn->data_copied);
877 BUG_ON(size <= 0);
878
879 rc = skb_copy_bits(conn->in.skb, conn->in.offset,
880 (char*)buf + conn->data_copied, size);
881 BUG_ON(rc);
882
883 conn->in.offset += size;
884 conn->in.copy -= size;
885 conn->in.copied += size;
886 conn->data_copied += size;
887
888 if (buf_size != conn->data_copied)
889 return -EAGAIN;
890
891 return 0;
892 }
893
894 static inline void
895 partial_sg_digest_update(struct iscsi_conn *conn, struct scatterlist *sg,
896 int offset, int length)
897 {
898 struct scatterlist temp;
899
900 memcpy(&temp, sg, sizeof(struct scatterlist));
901 temp.offset = offset;
902 temp.length = length;
903 crypto_digest_update(conn->data_rx_tfm, &temp, 1);
904 }
905
906 static void
907 iscsi_recv_digest_update(struct iscsi_conn *conn, char* buf, int len)
908 {
909 struct scatterlist tmp;
910
911 sg_init_one(&tmp, buf, len);
912 crypto_digest_update(conn->data_rx_tfm, &tmp, 1);
913 }
914
915 static int iscsi_scsi_data_in(struct iscsi_conn *conn)
916 {
917 struct iscsi_cmd_task *ctask = conn->in.ctask;
918 struct scsi_cmnd *sc = ctask->sc;
919 struct scatterlist *sg;
920 int i, offset, rc = 0;
921
922 BUG_ON((void*)ctask != sc->SCp.ptr);
923
924 /*
925 * copying Data-In into the Scsi_Cmnd
926 */
927 if (!sc->use_sg) {
928 i = ctask->data_count;
929 rc = iscsi_ctask_copy(conn, ctask, sc->request_buffer,
930 sc->request_bufflen, ctask->data_offset);
931 if (rc == -EAGAIN)
932 return rc;
933 if (conn->datadgst_en)
934 iscsi_recv_digest_update(conn, sc->request_buffer, i);
935 rc = 0;
936 goto done;
937 }
938
939 offset = ctask->data_offset;
940 sg = sc->request_buffer;
941
942 if (ctask->data_offset)
943 for (i = 0; i < ctask->sg_count; i++)
944 offset -= sg[i].length;
945 /* we've passed through partial sg*/
946 if (offset < 0)
947 offset = 0;
948
949 for (i = ctask->sg_count; i < sc->use_sg; i++) {
950 char *dest;
951
952 dest = kmap_atomic(sg[i].page, KM_SOFTIRQ0);
953 rc = iscsi_ctask_copy(conn, ctask, dest + sg[i].offset,
954 sg[i].length, offset);
955 kunmap_atomic(dest, KM_SOFTIRQ0);
956 if (rc == -EAGAIN)
957 /* continue with the next SKB/PDU */
958 return rc;
959 if (!rc) {
960 if (conn->datadgst_en) {
961 if (!offset)
962 crypto_digest_update(conn->data_rx_tfm,
963 &sg[i], 1);
964 else
965 partial_sg_digest_update(conn, &sg[i],
966 sg[i].offset + offset,
967 sg[i].length - offset);
968 }
969 offset = 0;
970 ctask->sg_count++;
971 }
972
973 if (!ctask->data_count) {
974 if (rc && conn->datadgst_en)
975 /*
976 * data-in is complete, but buffer not...
977 */
978 partial_sg_digest_update(conn, &sg[i],
979 sg[i].offset, sg[i].length-rc);
980 rc = 0;
981 break;
982 }
983
984 if (!conn->in.copy)
985 return -EAGAIN;
986 }
987 BUG_ON(ctask->data_count);
988
989 done:
990 /* check for non-exceptional status */
991 if (conn->in.flags & ISCSI_FLAG_DATA_STATUS) {
992 debug_scsi("done [sc %lx res %d itt 0x%x]\n",
993 (long)sc, sc->result, ctask->itt);
994 conn->scsirsp_pdus_cnt++;
995 iscsi_ctask_cleanup(conn, ctask);
996 sc->scsi_done(sc);
997 }
998
999 return rc;
1000 }
1001
1002 static int
1003 iscsi_data_recv(struct iscsi_conn *conn)
1004 {
1005 struct iscsi_session *session = conn->session;
1006 int rc = 0;
1007
1008 switch(conn->in.opcode) {
1009 case ISCSI_OP_SCSI_DATA_IN:
1010 rc = iscsi_scsi_data_in(conn);
1011 break;
1012 case ISCSI_OP_SCSI_CMD_RSP: {
1013 /*
1014 * SCSI Sense Data:
1015 * copying the entire Data Segment.
1016 */
1017 if (iscsi_tcp_copy(conn, conn->data, conn->in.datalen)) {
1018 rc = -EAGAIN;
1019 goto exit;
1020 }
1021
1022 /*
1023 * check for sense
1024 */
1025 conn->in.hdr = &conn->hdr;
1026 conn->senselen = (conn->data[0] << 8) | conn->data[1];
1027 rc = iscsi_cmd_rsp(conn, conn->in.ctask);
1028 if (!rc && conn->datadgst_en)
1029 iscsi_recv_digest_update(conn, conn->data,
1030 conn->in.datalen);
1031 }
1032 break;
1033 case ISCSI_OP_TEXT_RSP:
1034 case ISCSI_OP_LOGIN_RSP:
1035 case ISCSI_OP_NOOP_IN: {
1036 struct iscsi_mgmt_task *mtask = NULL;
1037
1038 if (conn->in.itt != ISCSI_RESERVED_TAG)
1039 mtask = (struct iscsi_mgmt_task *)
1040 session->mgmt_cmds[conn->in.itt -
1041 ISCSI_MGMT_ITT_OFFSET];
1042
1043 /*
1044 * Collect data segment to the connection's data
1045 * placeholder
1046 */
1047 if (iscsi_tcp_copy(conn, conn->data, conn->in.datalen)) {
1048 rc = -EAGAIN;
1049 goto exit;
1050 }
1051
1052 rc = iscsi_recv_pdu(iscsi_handle(conn), conn->in.hdr,
1053 conn->data, conn->in.datalen);
1054
1055 if (!rc && conn->datadgst_en &&
1056 conn->in.opcode != ISCSI_OP_LOGIN_RSP)
1057 iscsi_recv_digest_update(conn, conn->data,
1058 conn->in.datalen);
1059
1060 if (mtask && conn->login_mtask != mtask) {
1061 spin_lock(&session->lock);
1062 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1063 sizeof(void*));
1064 spin_unlock(&session->lock);
1065 }
1066 }
1067 break;
1068 case ISCSI_OP_ASYNC_EVENT:
1069 case ISCSI_OP_REJECT:
1070 default:
1071 BUG_ON(1);
1072 }
1073 exit:
1074 return rc;
1075 }
1076
1077 /**
1078 * iscsi_tcp_data_recv - TCP receive in sendfile fashion
1079 * @rd_desc: read descriptor
1080 * @skb: socket buffer
1081 * @offset: offset in skb
1082 * @len: skb->len - offset
1083 **/
1084 static int
1085 iscsi_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
1086 unsigned int offset, size_t len)
1087 {
1088 int rc;
1089 struct iscsi_conn *conn = rd_desc->arg.data;
1090 int processed;
1091 char pad[ISCSI_PAD_LEN];
1092 struct scatterlist sg;
1093
1094 /*
1095 * Save current SKB and its offset in the corresponding
1096 * connection context.
1097 */
1098 conn->in.copy = skb->len - offset;
1099 conn->in.offset = offset;
1100 conn->in.skb = skb;
1101 conn->in.len = conn->in.copy;
1102 BUG_ON(conn->in.copy <= 0);
1103 debug_tcp("in %d bytes\n", conn->in.copy);
1104
1105 more:
1106 conn->in.copied = 0;
1107 rc = 0;
1108
1109 if (unlikely(conn->suspend_rx)) {
1110 debug_tcp("conn %d Rx suspended!\n", conn->id);
1111 return 0;
1112 }
1113
1114 if (conn->in_progress == IN_PROGRESS_WAIT_HEADER ||
1115 conn->in_progress == IN_PROGRESS_HEADER_GATHER) {
1116 rc = iscsi_hdr_extract(conn);
1117 if (rc) {
1118 if (rc == -EAGAIN)
1119 goto nomore;
1120 else {
1121 iscsi_conn_failure(conn, rc);
1122 return 0;
1123 }
1124 }
1125
1126 /*
1127 * Verify and process incoming PDU header.
1128 */
1129 rc = iscsi_hdr_recv(conn);
1130 if (!rc && conn->in.datalen) {
1131 if (conn->datadgst_en &&
1132 conn->in.opcode != ISCSI_OP_LOGIN_RSP) {
1133 BUG_ON(!conn->data_rx_tfm);
1134 crypto_digest_init(conn->data_rx_tfm);
1135 }
1136 conn->in_progress = IN_PROGRESS_DATA_RECV;
1137 } else if (rc) {
1138 iscsi_conn_failure(conn, rc);
1139 return 0;
1140 }
1141 }
1142
1143 if (conn->in_progress == IN_PROGRESS_DDIGEST_RECV) {
1144 uint32_t recv_digest;
1145 debug_tcp("extra data_recv offset %d copy %d\n",
1146 conn->in.offset, conn->in.copy);
1147 skb_copy_bits(conn->in.skb, conn->in.offset,
1148 &recv_digest, 4);
1149 conn->in.offset += 4;
1150 conn->in.copy -= 4;
1151 if (recv_digest != conn->in.datadgst) {
1152 debug_tcp("iscsi_tcp: data digest error!"
1153 "0x%x != 0x%x\n", recv_digest,
1154 conn->in.datadgst);
1155 iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
1156 return 0;
1157 } else {
1158 debug_tcp("iscsi_tcp: data digest match!"
1159 "0x%x == 0x%x\n", recv_digest,
1160 conn->in.datadgst);
1161 conn->in_progress = IN_PROGRESS_WAIT_HEADER;
1162 }
1163 }
1164
1165 if (conn->in_progress == IN_PROGRESS_DATA_RECV && conn->in.copy) {
1166
1167 debug_tcp("data_recv offset %d copy %d\n",
1168 conn->in.offset, conn->in.copy);
1169
1170 rc = iscsi_data_recv(conn);
1171 if (rc) {
1172 if (rc == -EAGAIN) {
1173 rd_desc->count = conn->in.datalen -
1174 conn->in.ctask->data_count;
1175 goto again;
1176 }
1177 iscsi_conn_failure(conn, rc);
1178 return 0;
1179 }
1180 conn->in.copy -= conn->in.padding;
1181 conn->in.offset += conn->in.padding;
1182 if (conn->datadgst_en &&
1183 conn->in.opcode != ISCSI_OP_LOGIN_RSP) {
1184 if (conn->in.padding) {
1185 debug_tcp("padding -> %d\n", conn->in.padding);
1186 memset(pad, 0, conn->in.padding);
1187 sg_init_one(&sg, pad, conn->in.padding);
1188 crypto_digest_update(conn->data_rx_tfm, &sg, 1);
1189 }
1190 crypto_digest_final(conn->data_rx_tfm,
1191 (u8 *) & conn->in.datadgst);
1192 debug_tcp("rx digest 0x%x\n", conn->in.datadgst);
1193 conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
1194 } else
1195 conn->in_progress = IN_PROGRESS_WAIT_HEADER;
1196 }
1197
1198 debug_tcp("f, processed %d from out of %d padding %d\n",
1199 conn->in.offset - offset, (int)len, conn->in.padding);
1200 BUG_ON(conn->in.offset - offset > len);
1201
1202 if (conn->in.offset - offset != len) {
1203 debug_tcp("continue to process %d bytes\n",
1204 (int)len - (conn->in.offset - offset));
1205 goto more;
1206 }
1207
1208 nomore:
1209 processed = conn->in.offset - offset;
1210 BUG_ON(processed == 0);
1211 return processed;
1212
1213 again:
1214 processed = conn->in.offset - offset;
1215 debug_tcp("c, processed %d from out of %d rd_desc_cnt %d\n",
1216 processed, (int)len, (int)rd_desc->count);
1217 BUG_ON(processed == 0);
1218 BUG_ON(processed > len);
1219
1220 conn->rxdata_octets += processed;
1221 return processed;
1222 }
1223
1224 static void
1225 iscsi_tcp_data_ready(struct sock *sk, int flag)
1226 {
1227 struct iscsi_conn *conn = sk->sk_user_data;
1228 read_descriptor_t rd_desc;
1229
1230 read_lock(&sk->sk_callback_lock);
1231
1232 /* use rd_desc to pass 'conn' to iscsi_tcp_data_recv */
1233 rd_desc.arg.data = conn;
1234 rd_desc.count = 0;
1235 tcp_read_sock(sk, &rd_desc, iscsi_tcp_data_recv);
1236
1237 read_unlock(&sk->sk_callback_lock);
1238 }
1239
1240 static void
1241 iscsi_tcp_state_change(struct sock *sk)
1242 {
1243 struct iscsi_conn *conn;
1244 struct iscsi_session *session;
1245 void (*old_state_change)(struct sock *);
1246
1247 read_lock(&sk->sk_callback_lock);
1248
1249 conn = (struct iscsi_conn*)sk->sk_user_data;
1250 session = conn->session;
1251
1252 if ((sk->sk_state == TCP_CLOSE_WAIT ||
1253 sk->sk_state == TCP_CLOSE) &&
1254 !atomic_read(&sk->sk_rmem_alloc)) {
1255 debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
1256 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1257 }
1258
1259 old_state_change = conn->old_state_change;
1260
1261 read_unlock(&sk->sk_callback_lock);
1262
1263 old_state_change(sk);
1264 }
1265
1266 /**
1267 * iscsi_write_space - Called when more output buffer space is available
1268 * @sk: socket space is available for
1269 **/
1270 static void
1271 iscsi_write_space(struct sock *sk)
1272 {
1273 struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
1274 conn->old_write_space(sk);
1275 debug_tcp("iscsi_write_space: cid %d\n", conn->id);
1276 clear_bit(SUSPEND_BIT, &conn->suspend_tx);
1277 schedule_work(&conn->xmitwork);
1278 }
1279
1280 static void
1281 iscsi_conn_set_callbacks(struct iscsi_conn *conn)
1282 {
1283 struct sock *sk = conn->sock->sk;
1284
1285 /* assign new callbacks */
1286 write_lock_bh(&sk->sk_callback_lock);
1287 sk->sk_user_data = conn;
1288 conn->old_data_ready = sk->sk_data_ready;
1289 conn->old_state_change = sk->sk_state_change;
1290 conn->old_write_space = sk->sk_write_space;
1291 sk->sk_data_ready = iscsi_tcp_data_ready;
1292 sk->sk_state_change = iscsi_tcp_state_change;
1293 sk->sk_write_space = iscsi_write_space;
1294 write_unlock_bh(&sk->sk_callback_lock);
1295 }
1296
1297 static void
1298 iscsi_conn_restore_callbacks(struct iscsi_conn *conn)
1299 {
1300 struct sock *sk = conn->sock->sk;
1301
1302 /* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
1303 write_lock_bh(&sk->sk_callback_lock);
1304 sk->sk_user_data = NULL;
1305 sk->sk_data_ready = conn->old_data_ready;
1306 sk->sk_state_change = conn->old_state_change;
1307 sk->sk_write_space = conn->old_write_space;
1308 sk->sk_no_check = 0;
1309 write_unlock_bh(&sk->sk_callback_lock);
1310 }
1311
1312 /**
1313 * iscsi_send - generic send routine
1314 * @sk: kernel's socket
1315 * @buf: buffer to write from
1316 * @size: actual size to write
1317 * @flags: socket's flags
1318 *
1319 * Notes:
1320 * depending on buffer will use tcp_sendpage() or tcp_sendmsg().
1321 * buf->sg.offset == -1 tells us that buffer is non S/G and forces
1322 * to use tcp_sendmsg().
1323 */
1324 static inline int
1325 iscsi_send(struct socket *sk, struct iscsi_buf *buf, int size, int flags)
1326 {
1327 int res;
1328
1329 if ((int)buf->sg.offset >= 0) {
1330 int offset = buf->sg.offset + buf->sent;
1331
1332 /* tcp_sendpage */
1333 res = sk->ops->sendpage(sk, buf->sg.page, offset, size, flags);
1334 } else {
1335 struct msghdr msg;
1336
1337 buf->iov.iov_base = iscsi_buf_iov_base(buf);
1338 buf->iov.iov_len = size;
1339
1340 memset(&msg, 0, sizeof(struct msghdr));
1341
1342 /* tcp_sendmsg */
1343 res = kernel_sendmsg(sk, &msg, &buf->iov, 1, size);
1344 }
1345
1346 return res;
1347 }
1348
1349 /**
1350 * iscsi_sendhdr - send PDU Header via tcp_sendpage()
1351 * @conn: iscsi connection
1352 * @buf: buffer to write from
1353 * @datalen: lenght of data to be sent after the header
1354 *
1355 * Notes:
1356 * (Tx, Fast Path)
1357 **/
1358 static inline int
1359 iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
1360 {
1361 struct socket *sk = conn->sock;
1362 int flags = 0; /* MSG_DONTWAIT; */
1363 int res, size;
1364
1365 size = buf->sg.length - buf->sent;
1366 BUG_ON(buf->sent + size > buf->sg.length);
1367 if (buf->sent + size != buf->sg.length || datalen)
1368 flags |= MSG_MORE;
1369
1370 res = iscsi_send(sk, buf, size, flags);
1371 debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
1372 if (res >= 0) {
1373 conn->txdata_octets += res;
1374 buf->sent += res;
1375 if (size != res)
1376 return -EAGAIN;
1377 return 0;
1378 } else if (res == -EAGAIN) {
1379 conn->sendpage_failures_cnt++;
1380 set_bit(SUSPEND_BIT, &conn->suspend_tx);
1381 } else if (res == -EPIPE)
1382 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1383
1384 return res;
1385 }
1386
1387 /**
1388 * iscsi_sendpage - send one page of iSCSI Data-Out.
1389 * @conn: iscsi connection
1390 * @buf: buffer to write from
1391 * @count: remaining data
1392 * @sent: number of bytes sent
1393 *
1394 * Notes:
1395 * (Tx, Fast Path)
1396 **/
1397 static inline int
1398 iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
1399 int *count, int *sent)
1400 {
1401 struct socket *sk = conn->sock;
1402 int flags = 0; /* MSG_DONTWAIT; */
1403 int res, size;
1404
1405 size = buf->sg.length - buf->sent;
1406 BUG_ON(buf->sent + size > buf->sg.length);
1407 if (size > *count)
1408 size = *count;
1409 if (buf->sent + size != buf->sg.length || *count != size)
1410 flags |= MSG_MORE;
1411
1412 res = iscsi_send(sk, buf, size, flags);
1413 debug_tcp("sendpage: %d bytes, sent %d left %d sent %d res %d\n",
1414 size, buf->sent, *count, *sent, res);
1415 if (res >= 0) {
1416 conn->txdata_octets += res;
1417 buf->sent += res;
1418 *count -= res;
1419 *sent += res;
1420 if (size != res)
1421 return -EAGAIN;
1422 return 0;
1423 } else if (res == -EAGAIN) {
1424 conn->sendpage_failures_cnt++;
1425 set_bit(SUSPEND_BIT, &conn->suspend_tx);
1426 } else if (res == -EPIPE)
1427 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1428
1429 return res;
1430 }
1431
1432 static inline void
1433 iscsi_data_digest_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1434 {
1435 BUG_ON(!conn->data_tx_tfm);
1436 crypto_digest_init(conn->data_tx_tfm);
1437 ctask->digest_count = 4;
1438 }
1439
1440 static inline void
1441 iscsi_buf_data_digest_update(struct iscsi_conn *conn, struct iscsi_buf *buf)
1442 {
1443 struct scatterlist sg;
1444
1445 if (buf->sg.offset != -1)
1446 crypto_digest_update(conn->data_tx_tfm, &buf->sg, 1);
1447 else {
1448 sg_init_one(&sg, (char *)buf->sg.page, buf->sg.length);
1449 crypto_digest_update(conn->data_tx_tfm, &sg, 1);
1450 }
1451 }
1452
1453 static inline int
1454 iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1455 struct iscsi_buf *buf, uint32_t *digest, int final)
1456 {
1457 int rc = 0;
1458 int sent = 0;
1459
1460 if (final)
1461 crypto_digest_final(conn->data_tx_tfm, (u8*)digest);
1462
1463 iscsi_buf_init_virt(buf, (char*)digest, 4);
1464 rc = iscsi_sendpage(conn, buf, &ctask->digest_count, &sent);
1465 if (rc) {
1466 ctask->datadigest = *digest;
1467 ctask->xmstate |= XMSTATE_DATA_DIGEST;
1468 } else
1469 ctask->digest_count = 4;
1470 return rc;
1471 }
1472
1473 /**
1474 * iscsi_solicit_data_cont - initialize next Data-Out
1475 * @conn: iscsi connection
1476 * @ctask: scsi command task
1477 * @r2t: R2T info
1478 * @left: bytes left to transfer
1479 *
1480 * Notes:
1481 * Initialize next Data-Out within this R2T sequence and continue
1482 * to process next Scatter-Gather element(if any) of this SCSI command.
1483 *
1484 * Called under connection lock.
1485 **/
1486 static void
1487 iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1488 struct iscsi_r2t_info *r2t, int left)
1489 {
1490 struct iscsi_data *hdr;
1491 struct iscsi_data_task *dtask;
1492 struct scsi_cmnd *sc = ctask->sc;
1493 int new_offset;
1494
1495 dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
1496 BUG_ON(!dtask);
1497 hdr = &dtask->hdr;
1498 memset(hdr, 0, sizeof(struct iscsi_data));
1499 hdr->ttt = r2t->ttt;
1500 hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
1501 r2t->solicit_datasn++;
1502 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
1503 memcpy(hdr->lun, ctask->hdr.lun, sizeof(hdr->lun));
1504 hdr->itt = ctask->hdr.itt;
1505 hdr->exp_statsn = r2t->exp_statsn;
1506 new_offset = r2t->data_offset + r2t->sent;
1507 hdr->offset = cpu_to_be32(new_offset);
1508 if (left > conn->max_xmit_dlength) {
1509 hton24(hdr->dlength, conn->max_xmit_dlength);
1510 r2t->data_count = conn->max_xmit_dlength;
1511 } else {
1512 hton24(hdr->dlength, left);
1513 r2t->data_count = left;
1514 hdr->flags = ISCSI_FLAG_CMD_FINAL;
1515 }
1516 conn->dataout_pdus_cnt++;
1517
1518 iscsi_buf_init_virt(&r2t->headbuf, (char*)hdr,
1519 sizeof(struct iscsi_hdr));
1520
1521 r2t->dtask = dtask;
1522
1523 if (sc->use_sg && !iscsi_buf_left(&r2t->sendbuf)) {
1524 BUG_ON(ctask->bad_sg == r2t->sg);
1525 iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
1526 r2t->sg += 1;
1527 } else
1528 iscsi_buf_init_iov(&ctask->sendbuf,
1529 (char*)sc->request_buffer + new_offset,
1530 r2t->data_count);
1531
1532 list_add(&dtask->item, &ctask->dataqueue);
1533 }
1534
1535 static void
1536 iscsi_unsolicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1537 {
1538 struct iscsi_data *hdr;
1539 struct iscsi_data_task *dtask;
1540
1541 dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
1542 BUG_ON(!dtask);
1543 hdr = &dtask->hdr;
1544 memset(hdr, 0, sizeof(struct iscsi_data));
1545 hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
1546 hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
1547 ctask->unsol_datasn++;
1548 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
1549 memcpy(hdr->lun, ctask->hdr.lun, sizeof(hdr->lun));
1550 hdr->itt = ctask->hdr.itt;
1551 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
1552 hdr->offset = cpu_to_be32(ctask->total_length -
1553 ctask->r2t_data_count -
1554 ctask->unsol_count);
1555 if (ctask->unsol_count > conn->max_xmit_dlength) {
1556 hton24(hdr->dlength, conn->max_xmit_dlength);
1557 ctask->data_count = conn->max_xmit_dlength;
1558 hdr->flags = 0;
1559 } else {
1560 hton24(hdr->dlength, ctask->unsol_count);
1561 ctask->data_count = ctask->unsol_count;
1562 hdr->flags = ISCSI_FLAG_CMD_FINAL;
1563 }
1564
1565 iscsi_buf_init_virt(&ctask->headbuf, (char*)hdr,
1566 sizeof(struct iscsi_hdr));
1567
1568 list_add(&dtask->item, &ctask->dataqueue);
1569
1570 ctask->dtask = dtask;
1571 }
1572
1573 /**
1574 * iscsi_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
1575 * @conn: iscsi connection
1576 * @ctask: scsi command task
1577 * @sc: scsi command
1578 **/
1579 static void
1580 iscsi_cmd_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1581 struct scsi_cmnd *sc)
1582 {
1583 struct iscsi_session *session = conn->session;
1584
1585 BUG_ON(__kfifo_len(ctask->r2tqueue));
1586
1587 ctask->sc = sc;
1588 ctask->conn = conn;
1589 ctask->hdr.opcode = ISCSI_OP_SCSI_CMD;
1590 ctask->hdr.flags = ISCSI_ATTR_SIMPLE;
1591 int_to_scsilun(sc->device->lun, (struct scsi_lun *)ctask->hdr.lun);
1592 ctask->hdr.itt = ctask->itt | (conn->id << CID_SHIFT) |
1593 (session->age << AGE_SHIFT);
1594 ctask->hdr.data_length = cpu_to_be32(sc->request_bufflen);
1595 ctask->hdr.cmdsn = cpu_to_be32(session->cmdsn); session->cmdsn++;
1596 ctask->hdr.exp_statsn = cpu_to_be32(conn->exp_statsn);
1597 memcpy(ctask->hdr.cdb, sc->cmnd, sc->cmd_len);
1598 memset(&ctask->hdr.cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
1599
1600 ctask->mtask = NULL;
1601 ctask->sent = 0;
1602 ctask->sg_count = 0;
1603
1604 ctask->total_length = sc->request_bufflen;
1605
1606 if (sc->sc_data_direction == DMA_TO_DEVICE) {
1607 ctask->exp_r2tsn = 0;
1608 ctask->hdr.flags |= ISCSI_FLAG_CMD_WRITE;
1609 BUG_ON(ctask->total_length == 0);
1610 if (sc->use_sg) {
1611 struct scatterlist *sg = sc->request_buffer;
1612
1613 iscsi_buf_init_sg(&ctask->sendbuf,
1614 &sg[ctask->sg_count++]);
1615 ctask->sg = sg;
1616 ctask->bad_sg = sg + sc->use_sg;
1617 } else {
1618 iscsi_buf_init_iov(&ctask->sendbuf, sc->request_buffer,
1619 sc->request_bufflen);
1620 }
1621
1622 /*
1623 * Write counters:
1624 *
1625 * imm_count bytes to be sent right after
1626 * SCSI PDU Header
1627 *
1628 * unsol_count bytes(as Data-Out) to be sent
1629 * without R2T ack right after
1630 * immediate data
1631 *
1632 * r2t_data_count bytes to be sent via R2T ack's
1633 *
1634 * pad_count bytes to be sent as zero-padding
1635 */
1636 ctask->imm_count = 0;
1637 ctask->unsol_count = 0;
1638 ctask->unsol_datasn = 0;
1639 ctask->xmstate = XMSTATE_W_HDR;
1640 /* calculate write padding */
1641 ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
1642 if (ctask->pad_count) {
1643 ctask->pad_count = ISCSI_PAD_LEN - ctask->pad_count;
1644 debug_scsi("write padding %d bytes\n",
1645 ctask->pad_count);
1646 ctask->xmstate |= XMSTATE_W_PAD;
1647 }
1648 if (session->imm_data_en) {
1649 if (ctask->total_length >= session->first_burst)
1650 ctask->imm_count = min(session->first_burst,
1651 conn->max_xmit_dlength);
1652 else
1653 ctask->imm_count = min(ctask->total_length,
1654 conn->max_xmit_dlength);
1655 hton24(ctask->hdr.dlength, ctask->imm_count);
1656 ctask->xmstate |= XMSTATE_IMM_DATA;
1657 } else
1658 zero_data(ctask->hdr.dlength);
1659
1660 if (!session->initial_r2t_en)
1661 ctask->unsol_count = min(session->first_burst,
1662 ctask->total_length) - ctask->imm_count;
1663 if (!ctask->unsol_count)
1664 /* No unsolicit Data-Out's */
1665 ctask->hdr.flags |= ISCSI_FLAG_CMD_FINAL;
1666 else
1667 ctask->xmstate |= XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
1668
1669 ctask->r2t_data_count = ctask->total_length -
1670 ctask->imm_count -
1671 ctask->unsol_count;
1672
1673 debug_scsi("cmd [itt %x total %d imm %d imm_data %d "
1674 "r2t_data %d]\n",
1675 ctask->itt, ctask->total_length, ctask->imm_count,
1676 ctask->unsol_count, ctask->r2t_data_count);
1677 } else {
1678 ctask->hdr.flags |= ISCSI_FLAG_CMD_FINAL;
1679 if (sc->sc_data_direction == DMA_FROM_DEVICE)
1680 ctask->hdr.flags |= ISCSI_FLAG_CMD_READ;
1681 ctask->datasn = 0;
1682 ctask->xmstate = XMSTATE_R_HDR;
1683 zero_data(ctask->hdr.dlength);
1684 }
1685
1686 iscsi_buf_init_virt(&ctask->headbuf, (char*)&ctask->hdr,
1687 sizeof(struct iscsi_hdr));
1688 conn->scsicmd_pdus_cnt++;
1689 }
1690
1691 /**
1692 * iscsi_mtask_xmit - xmit management(immediate) task
1693 * @conn: iscsi connection
1694 * @mtask: task management task
1695 *
1696 * Notes:
1697 * The function can return -EAGAIN in which case caller must
1698 * call it again later, or recover. '0' return code means successful
1699 * xmit.
1700 *
1701 * Management xmit state machine consists of two states:
1702 * IN_PROGRESS_IMM_HEAD - PDU Header xmit in progress
1703 * IN_PROGRESS_IMM_DATA - PDU Data xmit in progress
1704 **/
1705 static int
1706 iscsi_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
1707 {
1708
1709 debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
1710 conn->id, mtask->xmstate, mtask->itt);
1711
1712 if (mtask->xmstate & XMSTATE_IMM_HDR) {
1713 mtask->xmstate &= ~XMSTATE_IMM_HDR;
1714 if (mtask->data_count)
1715 mtask->xmstate |= XMSTATE_IMM_DATA;
1716 if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
1717 conn->stop_stage != STOP_CONN_RECOVER &&
1718 conn->hdrdgst_en)
1719 iscsi_hdr_digest(conn, &mtask->headbuf,
1720 (u8*)mtask->hdrext);
1721 if (iscsi_sendhdr(conn, &mtask->headbuf, mtask->data_count)) {
1722 mtask->xmstate |= XMSTATE_IMM_HDR;
1723 if (mtask->data_count)
1724 mtask->xmstate &= ~XMSTATE_IMM_DATA;
1725 return -EAGAIN;
1726 }
1727 }
1728
1729 if (mtask->xmstate & XMSTATE_IMM_DATA) {
1730 BUG_ON(!mtask->data_count);
1731 mtask->xmstate &= ~XMSTATE_IMM_DATA;
1732 /* FIXME: implement.
1733 * Virtual buffer could be spreaded across multiple pages...
1734 */
1735 do {
1736 if (iscsi_sendpage(conn, &mtask->sendbuf,
1737 &mtask->data_count, &mtask->sent)) {
1738 mtask->xmstate |= XMSTATE_IMM_DATA;
1739 return -EAGAIN;
1740 }
1741 } while (mtask->data_count);
1742 }
1743
1744 BUG_ON(mtask->xmstate != XMSTATE_IDLE);
1745 return 0;
1746 }
1747
1748 static inline int
1749 handle_xmstate_r_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1750 {
1751 ctask->xmstate &= ~XMSTATE_R_HDR;
1752 if (conn->hdrdgst_en)
1753 iscsi_hdr_digest(conn, &ctask->headbuf, (u8*)ctask->hdrext);
1754 if (!iscsi_sendhdr(conn, &ctask->headbuf, 0)) {
1755 BUG_ON(ctask->xmstate != XMSTATE_IDLE);
1756 return 0; /* wait for Data-In */
1757 }
1758 ctask->xmstate |= XMSTATE_R_HDR;
1759 return -EAGAIN;
1760 }
1761
1762 static inline int
1763 handle_xmstate_w_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1764 {
1765 ctask->xmstate &= ~XMSTATE_W_HDR;
1766 if (conn->hdrdgst_en)
1767 iscsi_hdr_digest(conn, &ctask->headbuf, (u8*)ctask->hdrext);
1768 if (iscsi_sendhdr(conn, &ctask->headbuf, ctask->imm_count)) {
1769 ctask->xmstate |= XMSTATE_W_HDR;
1770 return -EAGAIN;
1771 }
1772 return 0;
1773 }
1774
1775 static inline int
1776 handle_xmstate_data_digest(struct iscsi_conn *conn,
1777 struct iscsi_cmd_task *ctask)
1778 {
1779 ctask->xmstate &= ~XMSTATE_DATA_DIGEST;
1780 debug_tcp("resent data digest 0x%x\n", ctask->datadigest);
1781 if (iscsi_digest_final_send(conn, ctask, &ctask->immbuf,
1782 &ctask->datadigest, 0)) {
1783 ctask->xmstate |= XMSTATE_DATA_DIGEST;
1784 debug_tcp("resent data digest 0x%x fail!\n",
1785 ctask->datadigest);
1786 return -EAGAIN;
1787 }
1788 return 0;
1789 }
1790
1791 static inline int
1792 handle_xmstate_imm_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1793 {
1794 BUG_ON(!ctask->imm_count);
1795 ctask->xmstate &= ~XMSTATE_IMM_DATA;
1796
1797 if (conn->datadgst_en) {
1798 iscsi_data_digest_init(conn, ctask);
1799 ctask->immdigest = 0;
1800 }
1801
1802 for (;;) {
1803 if (iscsi_sendpage(conn, &ctask->sendbuf, &ctask->imm_count,
1804 &ctask->sent)) {
1805 ctask->xmstate |= XMSTATE_IMM_DATA;
1806 if (conn->datadgst_en) {
1807 crypto_digest_final(conn->data_tx_tfm,
1808 (u8*)&ctask->immdigest);
1809 debug_tcp("tx imm sendpage fail 0x%x\n",
1810 ctask->datadigest);
1811 }
1812 return -EAGAIN;
1813 }
1814 if (conn->datadgst_en)
1815 iscsi_buf_data_digest_update(conn, &ctask->sendbuf);
1816
1817 if (!ctask->imm_count)
1818 break;
1819 iscsi_buf_init_sg(&ctask->sendbuf,
1820 &ctask->sg[ctask->sg_count++]);
1821 }
1822
1823 if (conn->datadgst_en && !(ctask->xmstate & XMSTATE_W_PAD)) {
1824 if (iscsi_digest_final_send(conn, ctask, &ctask->immbuf,
1825 &ctask->immdigest, 1)) {
1826 debug_tcp("sending imm digest 0x%x fail!\n",
1827 ctask->immdigest);
1828 return -EAGAIN;
1829 }
1830 debug_tcp("sending imm digest 0x%x\n", ctask->immdigest);
1831 }
1832
1833 return 0;
1834 }
1835
1836 static inline int
1837 handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1838 {
1839 struct iscsi_data_task *dtask;
1840
1841 ctask->xmstate |= XMSTATE_UNS_DATA;
1842 if (ctask->xmstate & XMSTATE_UNS_INIT) {
1843 iscsi_unsolicit_data_init(conn, ctask);
1844 BUG_ON(!ctask->dtask);
1845 dtask = ctask->dtask;
1846 if (conn->hdrdgst_en)
1847 iscsi_hdr_digest(conn, &ctask->headbuf,
1848 (u8*)dtask->hdrext);
1849 ctask->xmstate &= ~XMSTATE_UNS_INIT;
1850 }
1851 if (iscsi_sendhdr(conn, &ctask->headbuf, ctask->data_count)) {
1852 ctask->xmstate &= ~XMSTATE_UNS_DATA;
1853 ctask->xmstate |= XMSTATE_UNS_HDR;
1854 return -EAGAIN;
1855 }
1856
1857 debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
1858 ctask->itt, ctask->unsol_count, ctask->sent);
1859 return 0;
1860 }
1861
1862 static inline int
1863 handle_xmstate_uns_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1864 {
1865 struct iscsi_data_task *dtask = ctask->dtask;
1866
1867 BUG_ON(!ctask->data_count);
1868 ctask->xmstate &= ~XMSTATE_UNS_DATA;
1869
1870 if (conn->datadgst_en) {
1871 iscsi_data_digest_init(conn, ctask);
1872 dtask->digest = 0;
1873 }
1874
1875 for (;;) {
1876 int start = ctask->sent;
1877
1878 if (iscsi_sendpage(conn, &ctask->sendbuf, &ctask->data_count,
1879 &ctask->sent)) {
1880 ctask->unsol_count -= ctask->sent - start;
1881 ctask->xmstate |= XMSTATE_UNS_DATA;
1882 /* will continue with this ctask later.. */
1883 if (conn->datadgst_en) {
1884 crypto_digest_final(conn->data_tx_tfm,
1885 (u8 *)&dtask->digest);
1886 debug_tcp("tx uns data fail 0x%x\n",
1887 dtask->digest);
1888 }
1889 return -EAGAIN;
1890 }
1891
1892 BUG_ON(ctask->sent > ctask->total_length);
1893 ctask->unsol_count -= ctask->sent - start;
1894
1895 /*
1896 * XXX:we may run here with un-initial sendbuf.
1897 * so pass it
1898 */
1899 if (conn->datadgst_en && ctask->sent - start > 0)
1900 iscsi_buf_data_digest_update(conn, &ctask->sendbuf);
1901
1902 if (!ctask->data_count)
1903 break;
1904 iscsi_buf_init_sg(&ctask->sendbuf,
1905 &ctask->sg[ctask->sg_count++]);
1906 }
1907 BUG_ON(ctask->unsol_count < 0);
1908
1909 /*
1910 * Done with the Data-Out. Next, check if we need
1911 * to send another unsolicited Data-Out.
1912 */
1913 if (ctask->unsol_count) {
1914 if (conn->datadgst_en) {
1915 if (iscsi_digest_final_send(conn, ctask,
1916 &dtask->digestbuf,
1917 &dtask->digest, 1)) {
1918 debug_tcp("send uns digest 0x%x fail\n",
1919 dtask->digest);
1920 return -EAGAIN;
1921 }
1922 debug_tcp("sending uns digest 0x%x, more uns\n",
1923 dtask->digest);
1924 }
1925 ctask->xmstate |= XMSTATE_UNS_INIT;
1926 return 1;
1927 }
1928
1929 if (conn->datadgst_en && !(ctask->xmstate & XMSTATE_W_PAD)) {
1930 if (iscsi_digest_final_send(conn, ctask,
1931 &dtask->digestbuf,
1932 &dtask->digest, 1)) {
1933 debug_tcp("send last uns digest 0x%x fail\n",
1934 dtask->digest);
1935 return -EAGAIN;
1936 }
1937 debug_tcp("sending uns digest 0x%x\n",dtask->digest);
1938 }
1939
1940 return 0;
1941 }
1942
1943 static inline int
1944 handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1945 {
1946 struct iscsi_session *session = conn->session;
1947 struct iscsi_r2t_info *r2t = ctask->r2t;
1948 struct iscsi_data_task *dtask = r2t->dtask;
1949 int left;
1950
1951 ctask->xmstate &= ~XMSTATE_SOL_DATA;
1952 ctask->dtask = dtask;
1953
1954 if (conn->datadgst_en) {
1955 iscsi_data_digest_init(conn, ctask);
1956 dtask->digest = 0;
1957 }
1958 solicit_again:
1959 /*
1960 * send Data-Out whitnin this R2T sequence.
1961 */
1962 if (!r2t->data_count)
1963 goto data_out_done;
1964
1965 if (iscsi_sendpage(conn, &r2t->sendbuf, &r2t->data_count, &r2t->sent)) {
1966 ctask->xmstate |= XMSTATE_SOL_DATA;
1967 /* will continue with this ctask later.. */
1968 if (conn->datadgst_en) {
1969 crypto_digest_final(conn->data_tx_tfm,
1970 (u8 *)&dtask->digest);
1971 debug_tcp("r2t data send fail 0x%x\n", dtask->digest);
1972 }
1973 return -EAGAIN;
1974 }
1975
1976 BUG_ON(r2t->data_count < 0);
1977 if (conn->datadgst_en)
1978 iscsi_buf_data_digest_update(conn, &r2t->sendbuf);
1979
1980 if (r2t->data_count) {
1981 BUG_ON(ctask->sc->use_sg == 0);
1982 if (!iscsi_buf_left(&r2t->sendbuf)) {
1983 BUG_ON(ctask->bad_sg == r2t->sg);
1984 iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
1985 r2t->sg += 1;
1986 }
1987 goto solicit_again;
1988 }
1989
1990 data_out_done:
1991 /*
1992 * Done with this Data-Out. Next, check if we have
1993 * to send another Data-Out for this R2T.
1994 */
1995 BUG_ON(r2t->data_length - r2t->sent < 0);
1996 left = r2t->data_length - r2t->sent;
1997 if (left) {
1998 if (conn->datadgst_en) {
1999 if (iscsi_digest_final_send(conn, ctask,
2000 &dtask->digestbuf,
2001 &dtask->digest, 1)) {
2002 debug_tcp("send r2t data digest 0x%x"
2003 "fail\n", dtask->digest);
2004 return -EAGAIN;
2005 }
2006 debug_tcp("r2t data send digest 0x%x\n",
2007 dtask->digest);
2008 }
2009 iscsi_solicit_data_cont(conn, ctask, r2t, left);
2010 ctask->xmstate |= XMSTATE_SOL_DATA;
2011 ctask->xmstate &= ~XMSTATE_SOL_HDR;
2012 return 1;
2013 }
2014
2015 /*
2016 * Done with this R2T. Check if there are more
2017 * outstanding R2Ts ready to be processed.
2018 */
2019 BUG_ON(ctask->r2t_data_count - r2t->data_length < 0);
2020 if (conn->datadgst_en) {
2021 if (iscsi_digest_final_send(conn, ctask, &dtask->digestbuf,
2022 &dtask->digest, 1)) {
2023 debug_tcp("send last r2t data digest 0x%x"
2024 "fail\n", dtask->digest);
2025 return -EAGAIN;
2026 }
2027 debug_tcp("r2t done dout digest 0x%x\n", dtask->digest);
2028 }
2029
2030 ctask->r2t_data_count -= r2t->data_length;
2031 ctask->r2t = NULL;
2032 spin_lock_bh(&session->lock);
2033 __kfifo_put(ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
2034 spin_unlock_bh(&session->lock);
2035 if (__kfifo_get(ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
2036 ctask->r2t = r2t;
2037 ctask->xmstate |= XMSTATE_SOL_DATA;
2038 ctask->xmstate &= ~XMSTATE_SOL_HDR;
2039 return 1;
2040 }
2041
2042 return 0;
2043 }
2044
2045 static inline int
2046 handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
2047 {
2048 struct iscsi_data_task *dtask = ctask->dtask;
2049 int sent;
2050
2051 ctask->xmstate &= ~XMSTATE_W_PAD;
2052 iscsi_buf_init_virt(&ctask->sendbuf, (char*)&ctask->pad,
2053 ctask->pad_count);
2054 if (iscsi_sendpage(conn, &ctask->sendbuf, &ctask->pad_count, &sent)) {
2055 ctask->xmstate |= XMSTATE_W_PAD;
2056 return -EAGAIN;
2057 }
2058
2059 if (conn->datadgst_en) {
2060 iscsi_buf_data_digest_update(conn, &ctask->sendbuf);
2061 /* imm data? */
2062 if (!dtask) {
2063 if (iscsi_digest_final_send(conn, ctask, &ctask->immbuf,
2064 &ctask->immdigest, 1)) {
2065 debug_tcp("send padding digest 0x%x"
2066 "fail!\n", ctask->immdigest);
2067 return -EAGAIN;
2068 }
2069 debug_tcp("done with padding, digest 0x%x\n",
2070 ctask->datadigest);
2071 } else {
2072 if (iscsi_digest_final_send(conn, ctask,
2073 &dtask->digestbuf,
2074 &dtask->digest, 1)) {
2075 debug_tcp("send padding digest 0x%x"
2076 "fail\n", dtask->digest);
2077 return -EAGAIN;
2078 }
2079 debug_tcp("done with padding, digest 0x%x\n",
2080 dtask->digest);
2081 }
2082 }
2083
2084 return 0;
2085 }
2086
2087 static int
2088 iscsi_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
2089 {
2090 int rc = 0;
2091
2092 debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
2093 conn->id, ctask->xmstate, ctask->itt);
2094
2095 /*
2096 * serialize with TMF AbortTask
2097 */
2098 if (ctask->mtask)
2099 return rc;
2100
2101 if (ctask->xmstate & XMSTATE_R_HDR) {
2102 rc = handle_xmstate_r_hdr(conn, ctask);
2103 return rc;
2104 }
2105
2106 if (ctask->xmstate & XMSTATE_W_HDR) {
2107 rc = handle_xmstate_w_hdr(conn, ctask);
2108 if (rc)
2109 return rc;
2110 }
2111
2112 /* XXX: for data digest xmit recover */
2113 if (ctask->xmstate & XMSTATE_DATA_DIGEST) {
2114 rc = handle_xmstate_data_digest(conn, ctask);
2115 if (rc)
2116 return rc;
2117 }
2118
2119 if (ctask->xmstate & XMSTATE_IMM_DATA) {
2120 rc = handle_xmstate_imm_data(conn, ctask);
2121 if (rc)
2122 return rc;
2123 }
2124
2125 if (ctask->xmstate & XMSTATE_UNS_HDR) {
2126 BUG_ON(!ctask->unsol_count);
2127 ctask->xmstate &= ~XMSTATE_UNS_HDR;
2128 unsolicit_head_again:
2129 rc = handle_xmstate_uns_hdr(conn, ctask);
2130 if (rc)
2131 return rc;
2132 }
2133
2134 if (ctask->xmstate & XMSTATE_UNS_DATA) {
2135 rc = handle_xmstate_uns_data(conn, ctask);
2136 if (rc == 1)
2137 goto unsolicit_head_again;
2138 else if (rc)
2139 return rc;
2140 goto done;
2141 }
2142
2143 if (ctask->xmstate & XMSTATE_SOL_HDR) {
2144 struct iscsi_r2t_info *r2t;
2145
2146 ctask->xmstate &= ~XMSTATE_SOL_HDR;
2147 ctask->xmstate |= XMSTATE_SOL_DATA;
2148 if (!ctask->r2t)
2149 __kfifo_get(ctask->r2tqueue, (void*)&ctask->r2t,
2150 sizeof(void*));
2151 solicit_head_again:
2152 r2t = ctask->r2t;
2153 if (conn->hdrdgst_en)
2154 iscsi_hdr_digest(conn, &r2t->headbuf,
2155 (u8*)r2t->dtask->hdrext);
2156 if (iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count)) {
2157 ctask->xmstate &= ~XMSTATE_SOL_DATA;
2158 ctask->xmstate |= XMSTATE_SOL_HDR;
2159 return -EAGAIN;
2160 }
2161
2162 debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
2163 r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
2164 r2t->sent);
2165 }
2166
2167 if (ctask->xmstate & XMSTATE_SOL_DATA) {
2168 rc = handle_xmstate_sol_data(conn, ctask);
2169 if (rc == 1)
2170 goto solicit_head_again;
2171 if (rc)
2172 return rc;
2173 }
2174
2175 done:
2176 /*
2177 * Last thing to check is whether we need to send write
2178 * padding. Note that we check for xmstate equality, not just the bit.
2179 */
2180 if (ctask->xmstate == XMSTATE_W_PAD)
2181 rc = handle_xmstate_w_pad(conn, ctask);
2182
2183 return rc;
2184 }
2185
2186 /**
2187 * iscsi_data_xmit - xmit any command into the scheduled connection
2188 * @conn: iscsi connection
2189 *
2190 * Notes:
2191 * The function can return -EAGAIN in which case the caller must
2192 * re-schedule it again later or recover. '0' return code means
2193 * successful xmit.
2194 **/
2195 static int
2196 iscsi_data_xmit(struct iscsi_conn *conn)
2197 {
2198 if (unlikely(conn->suspend_tx)) {
2199 debug_tcp("conn %d Tx suspended!\n", conn->id);
2200 return 0;
2201 }
2202
2203 /*
2204 * Transmit in the following order:
2205 *
2206 * 1) un-finished xmit (ctask or mtask)
2207 * 2) immediate control PDUs
2208 * 3) write data
2209 * 4) SCSI commands
2210 * 5) non-immediate control PDUs
2211 *
2212 * No need to lock around __kfifo_get as long as
2213 * there's one producer and one consumer.
2214 */
2215
2216 BUG_ON(conn->ctask && conn->mtask);
2217
2218 if (conn->ctask) {
2219 if (iscsi_ctask_xmit(conn, conn->ctask))
2220 goto again;
2221 /* done with this in-progress ctask */
2222 conn->ctask = NULL;
2223 }
2224 if (conn->mtask) {
2225 if (iscsi_mtask_xmit(conn, conn->mtask))
2226 goto again;
2227 /* done with this in-progress mtask */
2228 conn->mtask = NULL;
2229 }
2230
2231 /* process immediate first */
2232 if (unlikely(__kfifo_len(conn->immqueue))) {
2233 struct iscsi_session *session = conn->session;
2234 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
2235 sizeof(void*))) {
2236 if (iscsi_mtask_xmit(conn, conn->mtask))
2237 goto again;
2238
2239 if (conn->mtask->hdr.itt ==
2240 cpu_to_be32(ISCSI_RESERVED_TAG)) {
2241 spin_lock_bh(&session->lock);
2242 __kfifo_put(session->mgmtpool.queue,
2243 (void*)&conn->mtask, sizeof(void*));
2244 spin_unlock_bh(&session->lock);
2245 }
2246 }
2247 /* done with this mtask */
2248 conn->mtask = NULL;
2249 }
2250
2251 /* process write queue */
2252 while (__kfifo_get(conn->writequeue, (void*)&conn->ctask,
2253 sizeof(void*))) {
2254 if (iscsi_ctask_xmit(conn, conn->ctask))
2255 goto again;
2256 }
2257
2258 /* process command queue */
2259 while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
2260 sizeof(void*))) {
2261 if (iscsi_ctask_xmit(conn, conn->ctask))
2262 goto again;
2263 }
2264 /* done with this ctask */
2265 conn->ctask = NULL;
2266
2267 /* process the rest control plane PDUs, if any */
2268 if (unlikely(__kfifo_len(conn->mgmtqueue))) {
2269 struct iscsi_session *session = conn->session;
2270
2271 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
2272 sizeof(void*))) {
2273 if (iscsi_mtask_xmit(conn, conn->mtask))
2274 goto again;
2275
2276 if (conn->mtask->hdr.itt ==
2277 cpu_to_be32(ISCSI_RESERVED_TAG)) {
2278 spin_lock_bh(&session->lock);
2279 __kfifo_put(session->mgmtpool.queue,
2280 (void*)&conn->mtask,
2281 sizeof(void*));
2282 spin_unlock_bh(&session->lock);
2283 }
2284 }
2285 /* done with this mtask */
2286 conn->mtask = NULL;
2287 }
2288
2289 return 0;
2290
2291 again:
2292 if (unlikely(conn->suspend_tx))
2293 return 0;
2294
2295 return -EAGAIN;
2296 }
2297
2298 static void
2299 iscsi_xmitworker(void *data)
2300 {
2301 struct iscsi_conn *conn = data;
2302
2303 /*
2304 * serialize Xmit worker on a per-connection basis.
2305 */
2306 down(&conn->xmitsema);
2307 if (iscsi_data_xmit(conn))
2308 schedule_work(&conn->xmitwork);
2309 up(&conn->xmitsema);
2310 }
2311
2312 #define FAILURE_BAD_HOST 1
2313 #define FAILURE_SESSION_FAILED 2
2314 #define FAILURE_SESSION_FREED 3
2315 #define FAILURE_WINDOW_CLOSED 4
2316 #define FAILURE_SESSION_TERMINATE 5
2317
2318 static int
2319 iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
2320 {
2321 struct Scsi_Host *host;
2322 int reason = 0;
2323 struct iscsi_session *session;
2324 struct iscsi_conn *conn = NULL;
2325 struct iscsi_cmd_task *ctask = NULL;
2326
2327 sc->scsi_done = done;
2328 sc->result = 0;
2329
2330 host = sc->device->host;
2331 session = iscsi_hostdata(host->hostdata);
2332 BUG_ON(host != session->host);
2333
2334 spin_lock(&session->lock);
2335
2336 if (session->state != ISCSI_STATE_LOGGED_IN) {
2337 if (session->state == ISCSI_STATE_FAILED) {
2338 reason = FAILURE_SESSION_FAILED;
2339 goto reject;
2340 } else if (session->state == ISCSI_STATE_TERMINATE) {
2341 reason = FAILURE_SESSION_TERMINATE;
2342 goto fault;
2343 }
2344 reason = FAILURE_SESSION_FREED;
2345 goto fault;
2346 }
2347
2348 /*
2349 * Check for iSCSI window and take care of CmdSN wrap-around
2350 */
2351 if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
2352 reason = FAILURE_WINDOW_CLOSED;
2353 goto reject;
2354 }
2355
2356 conn = session->leadconn;
2357
2358 __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
2359 BUG_ON(ctask->sc);
2360
2361 sc->SCp.phase = session->age;
2362 sc->SCp.ptr = (char*)ctask;
2363 iscsi_cmd_init(conn, ctask, sc);
2364
2365 __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
2366 debug_scsi(
2367 "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
2368 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
2369 conn->id, (long)sc, ctask->itt, sc->request_bufflen,
2370 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
2371 spin_unlock(&session->lock);
2372
2373 if (!in_interrupt() && !down_trylock(&conn->xmitsema)) {
2374 spin_unlock_irq(host->host_lock);
2375 if (iscsi_data_xmit(conn))
2376 schedule_work(&conn->xmitwork);
2377 up(&conn->xmitsema);
2378 spin_lock_irq(host->host_lock);
2379 } else
2380 schedule_work(&conn->xmitwork);
2381
2382 return 0;
2383
2384 reject:
2385 spin_unlock(&session->lock);
2386 debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
2387 return SCSI_MLQUEUE_HOST_BUSY;
2388
2389 fault:
2390 spin_unlock(&session->lock);
2391 printk(KERN_ERR "iscsi_tcp: cmd 0x%x is not queued (%d)\n",
2392 sc->cmnd[0], reason);
2393 sc->sense_buffer[0] = 0x70;
2394 sc->sense_buffer[2] = NOT_READY;
2395 sc->sense_buffer[7] = 0x6;
2396 sc->sense_buffer[12] = 0x08;
2397 sc->sense_buffer[13] = 0x00;
2398 sc->result = (DID_NO_CONNECT << 16);
2399 sc->resid = sc->request_bufflen;
2400 sc->scsi_done(sc);
2401 return 0;
2402 }
2403
2404 static int
2405 iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
2406 {
2407 if (depth > ISCSI_MAX_CMD_PER_LUN)
2408 depth = ISCSI_MAX_CMD_PER_LUN;
2409 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
2410 return sdev->queue_depth;
2411 }
2412
2413 static int
2414 iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
2415 {
2416 int i;
2417
2418 *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
2419 if (*items == NULL)
2420 return -ENOMEM;
2421
2422 q->max = max;
2423 q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
2424 if (q->pool == NULL) {
2425 kfree(*items);
2426 return -ENOMEM;
2427 }
2428
2429 q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
2430 GFP_KERNEL, NULL);
2431 if (q->queue == ERR_PTR(-ENOMEM)) {
2432 kfree(q->pool);
2433 kfree(*items);
2434 return -ENOMEM;
2435 }
2436
2437 for (i = 0; i < max; i++) {
2438 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
2439 if (q->pool[i] == NULL) {
2440 int j;
2441
2442 for (j = 0; j < i; j++)
2443 kfree(q->pool[j]);
2444
2445 kfifo_free(q->queue);
2446 kfree(q->pool);
2447 kfree(*items);
2448 return -ENOMEM;
2449 }
2450 memset(q->pool[i], 0, item_size);
2451 (*items)[i] = q->pool[i];
2452 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
2453 }
2454 return 0;
2455 }
2456
2457 static void
2458 iscsi_pool_free(struct iscsi_queue *q, void **items)
2459 {
2460 int i;
2461
2462 for (i = 0; i < q->max; i++)
2463 kfree(items[i]);
2464 kfree(q->pool);
2465 kfree(items);
2466 }
2467
2468 static iscsi_connh_t
2469 iscsi_conn_create(iscsi_sessionh_t sessionh, uint32_t conn_idx)
2470 {
2471 struct iscsi_session *session = iscsi_ptr(sessionh);
2472 struct iscsi_conn *conn = NULL;
2473
2474 conn = kmalloc(sizeof(struct iscsi_conn), GFP_KERNEL);
2475 if (conn == NULL)
2476 goto conn_alloc_fail;
2477 memset(conn, 0, sizeof(struct iscsi_conn));
2478
2479 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2480 conn->in_progress = IN_PROGRESS_WAIT_HEADER;
2481 conn->id = conn_idx;
2482 conn->exp_statsn = 0;
2483 conn->tmabort_state = TMABORT_INITIAL;
2484
2485 /* initial operational parameters */
2486 conn->hdr_size = sizeof(struct iscsi_hdr);
2487 conn->data_size = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
2488 conn->max_recv_dlength = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
2489
2490 spin_lock_init(&conn->lock);
2491
2492 /* initialize general xmit PDU commands queue */
2493 conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
2494 GFP_KERNEL, NULL);
2495 if (conn->xmitqueue == ERR_PTR(-ENOMEM))
2496 goto xmitqueue_alloc_fail;
2497
2498 /* initialize write response PDU commands queue */
2499 conn->writequeue = kfifo_alloc(session->cmds_max * sizeof(void*),
2500 GFP_KERNEL, NULL);
2501 if (conn->writequeue == ERR_PTR(-ENOMEM))
2502 goto writequeue_alloc_fail;
2503
2504 /* initialize general immediate & non-immediate PDU commands queue */
2505 conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
2506 GFP_KERNEL, NULL);
2507 if (conn->immqueue == ERR_PTR(-ENOMEM))
2508 goto immqueue_alloc_fail;
2509
2510 conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
2511 GFP_KERNEL, NULL);
2512 if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
2513 goto mgmtqueue_alloc_fail;
2514
2515 INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
2516
2517 /* allocate login_mtask used for the login/text sequences */
2518 spin_lock_bh(&session->lock);
2519 if (!__kfifo_get(session->mgmtpool.queue,
2520 (void*)&conn->login_mtask,
2521 sizeof(void*))) {
2522 spin_unlock_bh(&session->lock);
2523 goto login_mtask_alloc_fail;
2524 }
2525 spin_unlock_bh(&session->lock);
2526
2527 /* allocate initial PDU receive place holder */
2528 if (conn->data_size <= PAGE_SIZE)
2529 conn->data = kmalloc(conn->data_size, GFP_KERNEL);
2530 else
2531 conn->data = (void*)__get_free_pages(GFP_KERNEL,
2532 get_order(conn->data_size));
2533 if (!conn->data)
2534 goto max_recv_dlenght_alloc_fail;
2535
2536 init_timer(&conn->tmabort_timer);
2537 init_MUTEX(&conn->xmitsema);
2538 init_waitqueue_head(&conn->ehwait);
2539
2540 return iscsi_handle(conn);
2541
2542 max_recv_dlenght_alloc_fail:
2543 spin_lock_bh(&session->lock);
2544 __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2545 sizeof(void*));
2546 spin_unlock_bh(&session->lock);
2547 login_mtask_alloc_fail:
2548 kfifo_free(conn->mgmtqueue);
2549 mgmtqueue_alloc_fail:
2550 kfifo_free(conn->immqueue);
2551 immqueue_alloc_fail:
2552 kfifo_free(conn->writequeue);
2553 writequeue_alloc_fail:
2554 kfifo_free(conn->xmitqueue);
2555 xmitqueue_alloc_fail:
2556 kfree(conn);
2557 conn_alloc_fail:
2558 return iscsi_handle(NULL);
2559 }
2560
2561 static void
2562 iscsi_conn_destroy(iscsi_connh_t connh)
2563 {
2564 struct iscsi_conn *conn = iscsi_ptr(connh);
2565 struct iscsi_session *session = conn->session;
2566
2567 down(&conn->xmitsema);
2568 set_bit(SUSPEND_BIT, &conn->suspend_tx);
2569 if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE && conn->sock) {
2570 struct sock *sk = conn->sock->sk;
2571
2572 /*
2573 * conn_start() has never been called!
2574 * need to cleanup the socket.
2575 */
2576 write_lock_bh(&sk->sk_callback_lock);
2577 set_bit(SUSPEND_BIT, &conn->suspend_rx);
2578 write_unlock_bh(&sk->sk_callback_lock);
2579
2580 sock_hold(conn->sock->sk);
2581 iscsi_conn_restore_callbacks(conn);
2582 sock_put(conn->sock->sk);
2583 sock_release(conn->sock);
2584 conn->sock = NULL;
2585 }
2586
2587 spin_lock_bh(&session->lock);
2588 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2589 if (session->leadconn == conn) {
2590 /*
2591 * leading connection? then give up on recovery.
2592 */
2593 session->state = ISCSI_STATE_TERMINATE;
2594 wake_up(&conn->ehwait);
2595 }
2596 spin_unlock_bh(&session->lock);
2597
2598 up(&conn->xmitsema);
2599
2600 /*
2601 * Block until all in-progress commands for this connection
2602 * time out or fail.
2603 */
2604 for (;;) {
2605 spin_lock_bh(&conn->lock);
2606 if (!session->host->host_busy) { /* OK for ERL == 0 */
2607 spin_unlock_bh(&conn->lock);
2608 break;
2609 }
2610 spin_unlock_bh(&conn->lock);
2611 msleep_interruptible(500);
2612 printk("conn_destroy(): host_busy %d host_failed %d\n",
2613 session->host->host_busy, session->host->host_failed);
2614 /*
2615 * force eh_abort() to unblock
2616 */
2617 wake_up(&conn->ehwait);
2618 }
2619
2620 /* now free crypto */
2621 if (conn->hdrdgst_en || conn->datadgst_en) {
2622 if (conn->tx_tfm)
2623 crypto_free_tfm(conn->tx_tfm);
2624 if (conn->rx_tfm)
2625 crypto_free_tfm(conn->rx_tfm);
2626 if (conn->data_tx_tfm)
2627 crypto_free_tfm(conn->data_tx_tfm);
2628 if (conn->data_rx_tfm)
2629 crypto_free_tfm(conn->data_rx_tfm);
2630 }
2631
2632 /* free conn->data, size = MaxRecvDataSegmentLength */
2633 if (conn->data_size <= PAGE_SIZE)
2634 kfree(conn->data);
2635 else
2636 free_pages((unsigned long)conn->data,
2637 get_order(conn->data_size));
2638
2639 spin_lock_bh(&session->lock);
2640 __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
2641 sizeof(void*));
2642 list_del(&conn->item);
2643 if (list_empty(&session->connections))
2644 session->leadconn = NULL;
2645 if (session->leadconn && session->leadconn == conn)
2646 session->leadconn = container_of(session->connections.next,
2647 struct iscsi_conn, item);
2648
2649 if (session->leadconn == NULL)
2650 /* none connections exits.. reset sequencing */
2651 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
2652 spin_unlock_bh(&session->lock);
2653
2654 kfifo_free(conn->xmitqueue);
2655 kfifo_free(conn->writequeue);
2656 kfifo_free(conn->immqueue);
2657 kfifo_free(conn->mgmtqueue);
2658 kfree(conn);
2659 }
2660
2661 static int
2662 iscsi_conn_bind(iscsi_sessionh_t sessionh, iscsi_connh_t connh,
2663 uint32_t transport_fd, int is_leading)
2664 {
2665 struct iscsi_session *session = iscsi_ptr(sessionh);
2666 struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = iscsi_ptr(connh);
2667 struct sock *sk;
2668 struct socket *sock;
2669 int err;
2670
2671 /* lookup for existing socket */
2672 sock = sockfd_lookup(transport_fd, &err);
2673 if (!sock) {
2674 printk(KERN_ERR "iscsi_tcp: sockfd_lookup failed %d\n", err);
2675 return -EEXIST;
2676 }
2677
2678 /* lookup for existing connection */
2679 spin_lock_bh(&session->lock);
2680 list_for_each_entry(tmp, &session->connections, item) {
2681 if (tmp == conn) {
2682 if (conn->c_stage != ISCSI_CONN_STOPPED ||
2683 conn->stop_stage == STOP_CONN_TERM) {
2684 printk(KERN_ERR "iscsi_tcp: can't bind "
2685 "non-stopped connection (%d:%d)\n",
2686 conn->c_stage, conn->stop_stage);
2687 spin_unlock_bh(&session->lock);
2688 return -EIO;
2689 }
2690 break;
2691 }
2692 }
2693 if (tmp != conn) {
2694 /* bind new iSCSI connection to session */
2695 conn->session = session;
2696
2697 list_add(&conn->item, &session->connections);
2698 }
2699 spin_unlock_bh(&session->lock);
2700
2701 if (conn->stop_stage != STOP_CONN_SUSPEND) {
2702 /* bind iSCSI connection and socket */
2703 conn->sock = sock;
2704
2705 /* setup Socket parameters */
2706 sk = sock->sk;
2707 sk->sk_reuse = 1;
2708 sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
2709 sk->sk_allocation = GFP_ATOMIC;
2710
2711 /* FIXME: disable Nagle's algorithm */
2712
2713 /*
2714 * Intercept TCP callbacks for sendfile like receive
2715 * processing.
2716 */
2717 iscsi_conn_set_callbacks(conn);
2718
2719 /*
2720 * set receive state machine into initial state
2721 */
2722 conn->in_progress = IN_PROGRESS_WAIT_HEADER;
2723 }
2724
2725 if (is_leading)
2726 session->leadconn = conn;
2727
2728 /*
2729 * Unblock xmitworker(), Login Phase will pass through.
2730 */
2731 clear_bit(SUSPEND_BIT, &conn->suspend_rx);
2732 clear_bit(SUSPEND_BIT, &conn->suspend_tx);
2733
2734 return 0;
2735 }
2736
2737 static int
2738 iscsi_conn_start(iscsi_connh_t connh)
2739 {
2740 struct iscsi_conn *conn = iscsi_ptr(connh);
2741 struct iscsi_session *session = conn->session;
2742 struct sock *sk;
2743
2744 /* FF phase warming up... */
2745
2746 if (session == NULL) {
2747 printk(KERN_ERR "iscsi_tcp: can't start unbound connection\n");
2748 return -EPERM;
2749 }
2750
2751 sk = conn->sock->sk;
2752
2753 write_lock_bh(&sk->sk_callback_lock);
2754 spin_lock_bh(&session->lock);
2755 conn->c_stage = ISCSI_CONN_STARTED;
2756 session->state = ISCSI_STATE_LOGGED_IN;
2757
2758 switch(conn->stop_stage) {
2759 case STOP_CONN_RECOVER:
2760 /*
2761 * unblock eh_abort() if it is blocked. re-try all
2762 * commands after successful recovery
2763 */
2764 session->conn_cnt++;
2765 conn->stop_stage = 0;
2766 conn->tmabort_state = TMABORT_INITIAL;
2767 session->age++;
2768 wake_up(&conn->ehwait);
2769 break;
2770 case STOP_CONN_TERM:
2771 session->conn_cnt++;
2772 conn->stop_stage = 0;
2773 break;
2774 case STOP_CONN_SUSPEND:
2775 conn->stop_stage = 0;
2776 clear_bit(SUSPEND_BIT, &conn->suspend_rx);
2777 clear_bit(SUSPEND_BIT, &conn->suspend_tx);
2778 break;
2779 default:
2780 break;
2781 }
2782 spin_unlock_bh(&session->lock);
2783 write_unlock_bh(&sk->sk_callback_lock);
2784
2785 return 0;
2786 }
2787
2788 static void
2789 iscsi_conn_stop(iscsi_connh_t connh, int flag)
2790 {
2791 struct iscsi_conn *conn = iscsi_ptr(connh);
2792 struct iscsi_session *session = conn->session;
2793 struct sock *sk;
2794 unsigned long flags;
2795
2796 BUG_ON(!conn->sock);
2797 sk = conn->sock->sk;
2798 write_lock_bh(&sk->sk_callback_lock);
2799 set_bit(SUSPEND_BIT, &conn->suspend_rx);
2800 write_unlock_bh(&sk->sk_callback_lock);
2801
2802 down(&conn->xmitsema);
2803
2804 spin_lock_irqsave(session->host->host_lock, flags);
2805 spin_lock(&session->lock);
2806 conn->stop_stage = flag;
2807 conn->c_stage = ISCSI_CONN_STOPPED;
2808 set_bit(SUSPEND_BIT, &conn->suspend_tx);
2809
2810 if (flag != STOP_CONN_SUSPEND)
2811 session->conn_cnt--;
2812
2813 if (session->conn_cnt == 0 || session->leadconn == conn)
2814 session->state = ISCSI_STATE_FAILED;
2815
2816 spin_unlock(&session->lock);
2817 spin_unlock_irqrestore(session->host->host_lock, flags);
2818
2819 if (flag == STOP_CONN_TERM || flag == STOP_CONN_RECOVER) {
2820 struct iscsi_cmd_task *ctask;
2821 struct iscsi_mgmt_task *mtask;
2822
2823 /*
2824 * Socket must go now.
2825 */
2826 sock_hold(conn->sock->sk);
2827 iscsi_conn_restore_callbacks(conn);
2828 sock_put(conn->sock->sk);
2829
2830 /*
2831 * flush xmit queues.
2832 */
2833 spin_lock_bh(&session->lock);
2834 while (__kfifo_get(conn->writequeue, (void*)&ctask,
2835 sizeof(void*)) ||
2836 __kfifo_get(conn->xmitqueue, (void*)&ctask,
2837 sizeof(void*))) {
2838 struct iscsi_r2t_info *r2t;
2839
2840 /*
2841 * flush ctask's r2t queues
2842 */
2843 while (__kfifo_get(ctask->r2tqueue, (void*)&r2t,
2844 sizeof(void*)))
2845 __kfifo_put(ctask->r2tpool.queue, (void*)&r2t,
2846 sizeof(void*));
2847
2848 spin_unlock_bh(&session->lock);
2849 local_bh_disable();
2850 iscsi_ctask_cleanup(conn, ctask);
2851 local_bh_enable();
2852 spin_lock_bh(&session->lock);
2853 }
2854 conn->ctask = NULL;
2855 while (__kfifo_get(conn->immqueue, (void*)&mtask,
2856 sizeof(void*)) ||
2857 __kfifo_get(conn->mgmtqueue, (void*)&mtask,
2858 sizeof(void*))) {
2859 __kfifo_put(session->mgmtpool.queue,
2860 (void*)&mtask, sizeof(void*));
2861 }
2862 conn->mtask = NULL;
2863 spin_unlock_bh(&session->lock);
2864
2865 /*
2866 * release socket only after we stopped data_xmit()
2867 * activity and flushed all outstandings
2868 */
2869 sock_release(conn->sock);
2870 conn->sock = NULL;
2871
2872 /*
2873 * for connection level recovery we should not calculate
2874 * header digest. conn->hdr_size used for optimization
2875 * in hdr_extract() and will be re-negotiated at
2876 * set_param() time.
2877 */
2878 if (flag == STOP_CONN_RECOVER)
2879 conn->hdr_size = sizeof(struct iscsi_hdr);
2880 }
2881 up(&conn->xmitsema);
2882 }
2883
2884 static int
2885 iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
2886 char *data, uint32_t data_size)
2887 {
2888 struct iscsi_session *session = conn->session;
2889 struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
2890 struct iscsi_mgmt_task *mtask;
2891
2892 spin_lock_bh(&session->lock);
2893 if (session->state == ISCSI_STATE_TERMINATE) {
2894 spin_unlock_bh(&session->lock);
2895 return -EPERM;
2896 }
2897 if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
2898 hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
2899 /*
2900 * Login and Text are sent serially, in
2901 * request-followed-by-response sequence.
2902 * Same mtask can be used. Same ITT must be used.
2903 * Note that login_mtask is preallocated at conn_create().
2904 */
2905 mtask = conn->login_mtask;
2906 else {
2907 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
2908 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
2909
2910 if (!__kfifo_get(session->mgmtpool.queue,
2911 (void*)&mtask, sizeof(void*))) {
2912 spin_unlock_bh(&session->lock);
2913 return -ENOSPC;
2914 }
2915 }
2916
2917 /*
2918 * pre-format CmdSN and ExpStatSN for outgoing PDU.
2919 */
2920 if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
2921 hdr->itt = mtask->itt | (conn->id << CID_SHIFT) |
2922 (session->age << AGE_SHIFT);
2923 nop->cmdsn = cpu_to_be32(session->cmdsn);
2924 if (conn->c_stage == ISCSI_CONN_STARTED &&
2925 !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2926 session->cmdsn++;
2927 } else
2928 /* do not advance CmdSN */
2929 nop->cmdsn = cpu_to_be32(session->cmdsn);
2930
2931 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
2932
2933 memcpy(&mtask->hdr, hdr, sizeof(struct iscsi_hdr));
2934
2935 iscsi_buf_init_virt(&mtask->headbuf, (char*)&mtask->hdr,
2936 sizeof(struct iscsi_hdr));
2937
2938 spin_unlock_bh(&session->lock);
2939
2940 if (data_size) {
2941 memcpy(mtask->data, data, data_size);
2942 mtask->data_count = data_size;
2943 } else
2944 mtask->data_count = 0;
2945
2946 mtask->xmstate = XMSTATE_IMM_HDR;
2947
2948 if (mtask->data_count) {
2949 iscsi_buf_init_iov(&mtask->sendbuf, (char*)mtask->data,
2950 mtask->data_count);
2951 }
2952
2953 debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
2954 hdr->opcode, hdr->itt, data_size);
2955
2956 /*
2957 * since send_pdu() could be called at least from two contexts,
2958 * we need to serialize __kfifo_put, so we don't have to take
2959 * additional lock on fast data-path
2960 */
2961 if (hdr->opcode & ISCSI_OP_IMMEDIATE)
2962 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
2963 else
2964 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
2965
2966 schedule_work(&conn->xmitwork);
2967
2968 return 0;
2969 }
2970
2971 static int
2972 iscsi_eh_host_reset(struct scsi_cmnd *sc)
2973 {
2974 struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
2975 struct iscsi_conn *conn = ctask->conn;
2976 struct iscsi_session *session = conn->session;
2977
2978 spin_lock_bh(&session->lock);
2979 if (session->state == ISCSI_STATE_TERMINATE) {
2980 debug_scsi("failing host reset: session terminated "
2981 "[CID %d age %d]", conn->id, session->age);
2982 spin_unlock_bh(&session->lock);
2983 return FAILED;
2984 }
2985 spin_unlock_bh(&session->lock);
2986
2987 debug_scsi("failing connection CID %d due to SCSI host reset "
2988 "[itt 0x%x age %d]", conn->id, ctask->itt,
2989 session->age);
2990 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
2991
2992 return SUCCESS;
2993 }
2994
2995 static void
2996 iscsi_tmabort_timedout(unsigned long data)
2997 {
2998 struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
2999 struct iscsi_conn *conn = ctask->conn;
3000 struct iscsi_session *session = conn->session;
3001
3002 spin_lock(&session->lock);
3003 if (conn->tmabort_state == TMABORT_INITIAL) {
3004 __kfifo_put(session->mgmtpool.queue,
3005 (void*)&ctask->mtask, sizeof(void*));
3006 conn->tmabort_state = TMABORT_TIMEDOUT;
3007 debug_scsi("tmabort timedout [sc %lx itt 0x%x]\n",
3008 (long)ctask->sc, ctask->itt);
3009 /* unblock eh_abort() */
3010 wake_up(&conn->ehwait);
3011 }
3012 spin_unlock(&session->lock);
3013 }
3014
3015 static int
3016 iscsi_eh_abort(struct scsi_cmnd *sc)
3017 {
3018 int rc;
3019 struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
3020 struct iscsi_conn *conn = ctask->conn;
3021 struct iscsi_session *session = conn->session;
3022
3023 conn->eh_abort_cnt++;
3024 debug_scsi("aborting [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
3025
3026 /*
3027 * two cases for ERL=0 here:
3028 *
3029 * 1) connection-level failure;
3030 * 2) recovery due protocol error;
3031 */
3032 down(&conn->xmitsema);
3033 spin_lock_bh(&session->lock);
3034 if (session->state != ISCSI_STATE_LOGGED_IN) {
3035 if (session->state == ISCSI_STATE_TERMINATE) {
3036 spin_unlock_bh(&session->lock);
3037 up(&conn->xmitsema);
3038 goto failed;
3039 }
3040 spin_unlock_bh(&session->lock);
3041 } else {
3042 struct iscsi_tm *hdr = &conn->tmhdr;
3043
3044 /*
3045 * Still LOGGED_IN...
3046 */
3047
3048 if (!ctask->sc || sc->SCp.phase != session->age) {
3049 /*
3050 * 1) ctask completed before time out. But session
3051 * is still ok => Happy Retry.
3052 * 2) session was re-open during time out of ctask.
3053 */
3054 spin_unlock_bh(&session->lock);
3055 up(&conn->xmitsema);
3056 goto success;
3057 }
3058 conn->tmabort_state = TMABORT_INITIAL;
3059 spin_unlock_bh(&session->lock);
3060
3061 /*
3062 * ctask timed out but session is OK
3063 * ERL=0 requires task mgmt abort to be issued on each
3064 * failed command. requests must be serialized.
3065 */
3066 memset(hdr, 0, sizeof(struct iscsi_tm));
3067 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
3068 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
3069 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3070 memcpy(hdr->lun, ctask->hdr.lun, sizeof(hdr->lun));
3071 hdr->rtt = ctask->hdr.itt;
3072 hdr->refcmdsn = ctask->hdr.cmdsn;
3073
3074 rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
3075 NULL, 0);
3076 if (rc) {
3077 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
3078 debug_scsi("abort sent failure [itt 0x%x]", ctask->itt);
3079 } else {
3080 struct iscsi_r2t_info *r2t;
3081
3082 /*
3083 * TMF abort vs. TMF response race logic
3084 */
3085 spin_lock_bh(&session->lock);
3086 ctask->mtask = (struct iscsi_mgmt_task *)
3087 session->mgmt_cmds[(hdr->itt & ITT_MASK) -
3088 ISCSI_MGMT_ITT_OFFSET];
3089 /*
3090 * have to flush r2tqueue to avoid r2t leaks
3091 */
3092 while (__kfifo_get(ctask->r2tqueue, (void*)&r2t,
3093 sizeof(void*))) {
3094 __kfifo_put(ctask->r2tpool.queue, (void*)&r2t,
3095 sizeof(void*));
3096 }
3097 if (conn->tmabort_state == TMABORT_INITIAL) {
3098 conn->tmfcmd_pdus_cnt++;
3099 conn->tmabort_timer.expires = 3*HZ + jiffies;
3100 conn->tmabort_timer.function =
3101 iscsi_tmabort_timedout;
3102 conn->tmabort_timer.data = (unsigned long)ctask;
3103 add_timer(&conn->tmabort_timer);
3104 debug_scsi("abort sent [itt 0x%x]", ctask->itt);
3105 } else {
3106 if (!ctask->sc ||
3107 conn->tmabort_state == TMABORT_SUCCESS) {
3108 conn->tmabort_state = TMABORT_INITIAL;
3109 spin_unlock_bh(&session->lock);
3110 up(&conn->xmitsema);
3111 goto success;
3112 }
3113 conn->tmabort_state = TMABORT_INITIAL;
3114 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
3115 }
3116 spin_unlock_bh(&session->lock);
3117 }
3118 }
3119 up(&conn->xmitsema);
3120
3121
3122 /*
3123 * block eh thread until:
3124 *
3125 * 1) abort response;
3126 * 2) abort timeout;
3127 * 3) session re-opened;
3128 * 4) session terminated;
3129 */
3130 for (;;) {
3131 int p_state = session->state;
3132
3133 rc = wait_event_interruptible(conn->ehwait,
3134 (p_state == ISCSI_STATE_LOGGED_IN ?
3135 (session->state == ISCSI_STATE_TERMINATE ||
3136 conn->tmabort_state != TMABORT_INITIAL) :
3137 (session->state == ISCSI_STATE_TERMINATE ||
3138 session->state == ISCSI_STATE_LOGGED_IN)));
3139 if (rc) {
3140 /* shutdown.. */
3141 session->state = ISCSI_STATE_TERMINATE;
3142 goto failed;
3143 }
3144
3145 if (signal_pending(current))
3146 flush_signals(current);
3147
3148 if (session->state == ISCSI_STATE_TERMINATE)
3149 goto failed;
3150
3151 spin_lock_bh(&session->lock);
3152 if (sc->SCp.phase == session->age &&
3153 (conn->tmabort_state == TMABORT_TIMEDOUT ||
3154 conn->tmabort_state == TMABORT_FAILED)) {
3155 conn->tmabort_state = TMABORT_INITIAL;
3156 if (!ctask->sc) {
3157 /*
3158 * ctask completed before tmf abort response or
3159 * time out.
3160 * But session is still ok => Happy Retry.
3161 */
3162 spin_unlock_bh(&session->lock);
3163 break;
3164 }
3165 spin_unlock_bh(&session->lock);
3166 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
3167 continue;
3168 }
3169 spin_unlock_bh(&session->lock);
3170 break;
3171 }
3172
3173 success:
3174 debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
3175 rc = SUCCESS;
3176 goto exit;
3177
3178 failed:
3179 debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
3180 rc = FAILED;
3181
3182 exit:
3183 del_timer_sync(&conn->tmabort_timer);
3184
3185 down(&conn->xmitsema);
3186 if (conn->sock) {
3187 struct sock *sk = conn->sock->sk;
3188
3189 write_lock_bh(&sk->sk_callback_lock);
3190 iscsi_ctask_cleanup(conn, ctask);
3191 write_unlock_bh(&sk->sk_callback_lock);
3192 }
3193 up(&conn->xmitsema);
3194 return rc;
3195 }
3196
3197 static int
3198 iscsi_r2tpool_alloc(struct iscsi_session *session)
3199 {
3200 int i;
3201 int cmd_i;
3202
3203 /*
3204 * initialize per-task: R2T pool and xmit queue
3205 */
3206 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
3207 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
3208
3209 /*
3210 * pre-allocated x4 as much r2ts to handle race when
3211 * target acks DataOut faster than we data_xmit() queues
3212 * could replenish r2tqueue.
3213 */
3214
3215 /* R2T pool */
3216 if (iscsi_pool_init(&ctask->r2tpool, session->max_r2t * 4,
3217 (void***)&ctask->r2ts, sizeof(struct iscsi_r2t_info))) {
3218 goto r2t_alloc_fail;
3219 }
3220
3221 /* R2T xmit queue */
3222 ctask->r2tqueue = kfifo_alloc(
3223 session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
3224 if (ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
3225 iscsi_pool_free(&ctask->r2tpool, (void**)ctask->r2ts);
3226 goto r2t_alloc_fail;
3227 }
3228
3229 /*
3230 * number of
3231 * Data-Out PDU's within R2T-sequence can be quite big;
3232 * using mempool
3233 */
3234 ctask->datapool = mempool_create(ISCSI_DTASK_DEFAULT_MAX,
3235 mempool_alloc_slab, mempool_free_slab, taskcache);
3236 if (ctask->datapool == NULL) {
3237 kfifo_free(ctask->r2tqueue);
3238 iscsi_pool_free(&ctask->r2tpool, (void**)ctask->r2ts);
3239 goto r2t_alloc_fail;
3240 }
3241 INIT_LIST_HEAD(&ctask->dataqueue);
3242 }
3243
3244 return 0;
3245
3246 r2t_alloc_fail:
3247 for (i = 0; i < cmd_i; i++) {
3248 mempool_destroy(session->cmds[i]->datapool);
3249 kfifo_free(session->cmds[i]->r2tqueue);
3250 iscsi_pool_free(&session->cmds[i]->r2tpool,
3251 (void**)session->cmds[i]->r2ts);
3252 }
3253 return -ENOMEM;
3254 }
3255
3256 static void
3257 iscsi_r2tpool_free(struct iscsi_session *session)
3258 {
3259 int i;
3260
3261 for (i = 0; i < session->cmds_max; i++) {
3262 mempool_destroy(session->cmds[i]->datapool);
3263 kfifo_free(session->cmds[i]->r2tqueue);
3264 iscsi_pool_free(&session->cmds[i]->r2tpool,
3265 (void**)session->cmds[i]->r2ts);
3266 }
3267 }
3268
3269 static struct scsi_host_template iscsi_sht = {
3270 .name = "iSCSI Initiator over TCP/IP, v."
3271 ISCSI_VERSION_STR,
3272 .queuecommand = iscsi_queuecommand,
3273 .change_queue_depth = iscsi_change_queue_depth,
3274 .can_queue = ISCSI_XMIT_CMDS_MAX - 1,
3275 .sg_tablesize = ISCSI_SG_TABLESIZE,
3276 .cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
3277 .eh_abort_handler = iscsi_eh_abort,
3278 .eh_host_reset_handler = iscsi_eh_host_reset,
3279 .use_clustering = DISABLE_CLUSTERING,
3280 .proc_name = "iscsi_tcp",
3281 .this_id = -1,
3282 };
3283
3284 static iscsi_sessionh_t
3285 iscsi_session_create(uint32_t initial_cmdsn, struct Scsi_Host *host)
3286 {
3287 int cmd_i;
3288 struct iscsi_session *session;
3289
3290 session = iscsi_hostdata(host->hostdata);
3291 memset(session, 0, sizeof(struct iscsi_session));
3292
3293 session->host = host;
3294 session->id = host->host_no;
3295 session->state = ISCSI_STATE_LOGGED_IN;
3296 session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
3297 session->cmds_max = ISCSI_XMIT_CMDS_MAX;
3298 session->cmdsn = initial_cmdsn;
3299 session->exp_cmdsn = initial_cmdsn + 1;
3300 session->max_cmdsn = initial_cmdsn + 1;
3301 session->max_r2t = 1;
3302
3303 /* initialize SCSI PDU commands pool */
3304 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
3305 (void***)&session->cmds, sizeof(struct iscsi_cmd_task)))
3306 goto cmdpool_alloc_fail;
3307
3308 /* pre-format cmds pool with ITT */
3309 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++)
3310 session->cmds[cmd_i]->itt = cmd_i;
3311
3312 spin_lock_init(&session->lock);
3313 INIT_LIST_HEAD(&session->connections);
3314
3315 /* initialize immediate command pool */
3316 if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
3317 (void***)&session->mgmt_cmds, sizeof(struct iscsi_mgmt_task)))
3318 goto mgmtpool_alloc_fail;
3319
3320
3321 /* pre-format immediate cmds pool with ITT */
3322 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
3323 session->mgmt_cmds[cmd_i]->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
3324 session->mgmt_cmds[cmd_i]->data = kmalloc(
3325 DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
3326 if (!session->mgmt_cmds[cmd_i]->data) {
3327 int j;
3328
3329 for (j = 0; j < cmd_i; j++)
3330 kfree(session->mgmt_cmds[j]->data);
3331 goto immdata_alloc_fail;
3332 }
3333 }
3334
3335 if (iscsi_r2tpool_alloc(session))
3336 goto r2tpool_alloc_fail;
3337
3338 return iscsi_handle(session);
3339
3340 r2tpool_alloc_fail:
3341 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
3342 kfree(session->mgmt_cmds[cmd_i]->data);
3343 iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
3344 immdata_alloc_fail:
3345 mgmtpool_alloc_fail:
3346 iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
3347 cmdpool_alloc_fail:
3348 return iscsi_handle(NULL);
3349 }
3350
3351 static void
3352 iscsi_session_destroy(iscsi_sessionh_t sessionh)
3353 {
3354 int cmd_i;
3355 struct iscsi_data_task *dtask, *n;
3356 struct iscsi_session *session = iscsi_ptr(sessionh);
3357
3358 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
3359 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
3360 list_for_each_entry_safe(dtask, n, &ctask->dataqueue, item) {
3361 list_del(&dtask->item);
3362 mempool_free(dtask, ctask->datapool);
3363 }
3364 }
3365
3366 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
3367 kfree(session->mgmt_cmds[cmd_i]->data);
3368
3369 iscsi_r2tpool_free(session);
3370 iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
3371 iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
3372 }
3373
3374 static int
3375 iscsi_conn_set_param(iscsi_connh_t connh, enum iscsi_param param,
3376 uint32_t value)
3377 {
3378 struct iscsi_conn *conn = iscsi_ptr(connh);
3379 struct iscsi_session *session = conn->session;
3380
3381 spin_lock_bh(&session->lock);
3382 if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
3383 conn->stop_stage != STOP_CONN_RECOVER) {
3384 printk(KERN_ERR "iscsi_tcp: can not change parameter [%d]\n",
3385 param);
3386 spin_unlock_bh(&session->lock);
3387 return 0;
3388 }
3389 spin_unlock_bh(&session->lock);
3390
3391 switch(param) {
3392 case ISCSI_PARAM_MAX_RECV_DLENGTH: {
3393 char *saveptr = conn->data;
3394 int flags = GFP_KERNEL;
3395
3396 if (conn->data_size >= value) {
3397 conn->max_recv_dlength = value;
3398 break;
3399 }
3400
3401 spin_lock_bh(&session->lock);
3402 if (conn->stop_stage == STOP_CONN_RECOVER)
3403 flags = GFP_ATOMIC;
3404 spin_unlock_bh(&session->lock);
3405
3406 if (value <= PAGE_SIZE)
3407 conn->data = kmalloc(value, flags);
3408 else
3409 conn->data = (void*)__get_free_pages(flags,
3410 get_order(value));
3411 if (conn->data == NULL) {
3412 conn->data = saveptr;
3413 return -ENOMEM;
3414 }
3415 if (conn->data_size <= PAGE_SIZE)
3416 kfree(saveptr);
3417 else
3418 free_pages((unsigned long)saveptr,
3419 get_order(conn->data_size));
3420 conn->max_recv_dlength = value;
3421 conn->data_size = value;
3422 }
3423 break;
3424 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3425 conn->max_xmit_dlength = value;
3426 break;
3427 case ISCSI_PARAM_HDRDGST_EN:
3428 conn->hdrdgst_en = value;
3429 conn->hdr_size = sizeof(struct iscsi_hdr);
3430 if (conn->hdrdgst_en) {
3431 conn->hdr_size += sizeof(__u32);
3432 if (!conn->tx_tfm)
3433 conn->tx_tfm = crypto_alloc_tfm("crc32c", 0);
3434 if (!conn->tx_tfm)
3435 return -ENOMEM;
3436 if (!conn->rx_tfm)
3437 conn->rx_tfm = crypto_alloc_tfm("crc32c", 0);
3438 if (!conn->rx_tfm) {
3439 crypto_free_tfm(conn->tx_tfm);
3440 return -ENOMEM;
3441 }
3442 } else {
3443 if (conn->tx_tfm)
3444 crypto_free_tfm(conn->tx_tfm);
3445 if (conn->rx_tfm)
3446 crypto_free_tfm(conn->rx_tfm);
3447 }
3448 break;
3449 case ISCSI_PARAM_DATADGST_EN:
3450 conn->datadgst_en = value;
3451 if (conn->datadgst_en) {
3452 if (!conn->data_tx_tfm)
3453 conn->data_tx_tfm =
3454 crypto_alloc_tfm("crc32c", 0);
3455 if (!conn->data_tx_tfm)
3456 return -ENOMEM;
3457 if (!conn->data_rx_tfm)
3458 conn->data_rx_tfm =
3459 crypto_alloc_tfm("crc32c", 0);
3460 if (!conn->data_rx_tfm) {
3461 crypto_free_tfm(conn->data_tx_tfm);
3462 return -ENOMEM;
3463 }
3464 } else {
3465 if (conn->data_tx_tfm)
3466 crypto_free_tfm(conn->data_tx_tfm);
3467 if (conn->data_rx_tfm)
3468 crypto_free_tfm(conn->data_rx_tfm);
3469 }
3470 break;
3471 case ISCSI_PARAM_INITIAL_R2T_EN:
3472 session->initial_r2t_en = value;
3473 break;
3474 case ISCSI_PARAM_MAX_R2T:
3475 if (session->max_r2t == roundup_pow_of_two(value))
3476 break;
3477 iscsi_r2tpool_free(session);
3478 session->max_r2t = value;
3479 if (session->max_r2t & (session->max_r2t - 1))
3480 session->max_r2t = roundup_pow_of_two(session->max_r2t);
3481 if (iscsi_r2tpool_alloc(session))
3482 return -ENOMEM;
3483 break;
3484 case ISCSI_PARAM_IMM_DATA_EN:
3485 session->imm_data_en = value;
3486 break;
3487 case ISCSI_PARAM_FIRST_BURST:
3488 session->first_burst = value;
3489 break;
3490 case ISCSI_PARAM_MAX_BURST:
3491 session->max_burst = value;
3492 break;
3493 case ISCSI_PARAM_PDU_INORDER_EN:
3494 session->pdu_inorder_en = value;
3495 break;
3496 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3497 session->dataseq_inorder_en = value;
3498 break;
3499 case ISCSI_PARAM_ERL:
3500 session->erl = value;
3501 break;
3502 case ISCSI_PARAM_IFMARKER_EN:
3503 BUG_ON(value);
3504 session->ifmarker_en = value;
3505 break;
3506 case ISCSI_PARAM_OFMARKER_EN:
3507 BUG_ON(value);
3508 session->ofmarker_en = value;
3509 break;
3510 default:
3511 break;
3512 }
3513
3514 return 0;
3515 }
3516
3517 static int
3518 iscsi_conn_get_param(iscsi_connh_t connh, enum iscsi_param param,
3519 uint32_t *value)
3520 {
3521 struct iscsi_conn *conn = iscsi_ptr(connh);
3522 struct iscsi_session *session = conn->session;
3523
3524 switch(param) {
3525 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3526 *value = conn->max_recv_dlength;
3527 break;
3528 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3529 *value = conn->max_xmit_dlength;
3530 break;
3531 case ISCSI_PARAM_HDRDGST_EN:
3532 *value = conn->hdrdgst_en;
3533 break;
3534 case ISCSI_PARAM_DATADGST_EN:
3535 *value = conn->datadgst_en;
3536 break;
3537 case ISCSI_PARAM_INITIAL_R2T_EN:
3538 *value = session->initial_r2t_en;
3539 break;
3540 case ISCSI_PARAM_MAX_R2T:
3541 *value = session->max_r2t;
3542 break;
3543 case ISCSI_PARAM_IMM_DATA_EN:
3544 *value = session->imm_data_en;
3545 break;
3546 case ISCSI_PARAM_FIRST_BURST:
3547 *value = session->first_burst;
3548 break;
3549 case ISCSI_PARAM_MAX_BURST:
3550 *value = session->max_burst;
3551 break;
3552 case ISCSI_PARAM_PDU_INORDER_EN:
3553 *value = session->pdu_inorder_en;
3554 break;
3555 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3556 *value = session->dataseq_inorder_en;
3557 break;
3558 case ISCSI_PARAM_ERL:
3559 *value = session->erl;
3560 break;
3561 case ISCSI_PARAM_IFMARKER_EN:
3562 *value = session->ifmarker_en;
3563 break;
3564 case ISCSI_PARAM_OFMARKER_EN:
3565 *value = session->ofmarker_en;
3566 break;
3567 default:
3568 return ISCSI_ERR_PARAM_NOT_FOUND;
3569 }
3570
3571 return 0;
3572 }
3573
3574 static void
3575 iscsi_conn_get_stats(iscsi_connh_t connh, struct iscsi_stats *stats)
3576 {
3577 struct iscsi_conn *conn = iscsi_ptr(connh);
3578
3579 stats->txdata_octets = conn->txdata_octets;
3580 stats->rxdata_octets = conn->rxdata_octets;
3581 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
3582 stats->dataout_pdus = conn->dataout_pdus_cnt;
3583 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
3584 stats->datain_pdus = conn->datain_pdus_cnt;
3585 stats->r2t_pdus = conn->r2t_pdus_cnt;
3586 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
3587 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
3588 stats->custom_length = 3;
3589 strcpy(stats->custom[0].desc, "tx_sendpage_failures");
3590 stats->custom[0].value = conn->sendpage_failures_cnt;
3591 strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
3592 stats->custom[1].value = conn->discontiguous_hdr_cnt;
3593 strcpy(stats->custom[2].desc, "eh_abort_cnt");
3594 stats->custom[2].value = conn->eh_abort_cnt;
3595 }
3596
3597 static int
3598 iscsi_conn_send_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr, char *data,
3599 uint32_t data_size)
3600 {
3601 struct iscsi_conn *conn = iscsi_ptr(connh);
3602 int rc;
3603
3604 down(&conn->xmitsema);
3605 rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
3606 up(&conn->xmitsema);
3607
3608 return rc;
3609 }
3610
3611 static struct iscsi_transport iscsi_tcp_transport = {
3612 .owner = THIS_MODULE,
3613 .name = "tcp",
3614 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
3615 | CAP_DATADGST,
3616 .host_template = &iscsi_sht,
3617 .hostdata_size = sizeof(struct iscsi_session),
3618 .max_conn = 1,
3619 .max_cmd_len = ISCSI_TCP_MAX_CMD_LEN,
3620 .create_session = iscsi_session_create,
3621 .destroy_session = iscsi_session_destroy,
3622 .create_conn = iscsi_conn_create,
3623 .bind_conn = iscsi_conn_bind,
3624 .destroy_conn = iscsi_conn_destroy,
3625 .set_param = iscsi_conn_set_param,
3626 .get_param = iscsi_conn_get_param,
3627 .start_conn = iscsi_conn_start,
3628 .stop_conn = iscsi_conn_stop,
3629 .send_pdu = iscsi_conn_send_pdu,
3630 .get_stats = iscsi_conn_get_stats,
3631 };
3632
3633 static int __init
3634 iscsi_tcp_init(void)
3635 {
3636 int error;
3637
3638 if (iscsi_max_lun < 1) {
3639 printk(KERN_ERR "Invalid max_lun value of %u\n", iscsi_max_lun);
3640 return -EINVAL;
3641 }
3642 iscsi_tcp_transport.max_lun = iscsi_max_lun;
3643
3644 taskcache = kmem_cache_create("iscsi_taskcache",
3645 sizeof(struct iscsi_data_task), 0,
3646 SLAB_HWCACHE_ALIGN | SLAB_NO_REAP, NULL, NULL);
3647 if (!taskcache)
3648 return -ENOMEM;
3649
3650 error = iscsi_register_transport(&iscsi_tcp_transport);
3651 if (error)
3652 kmem_cache_destroy(taskcache);
3653
3654 return error;
3655 }
3656
3657 static void __exit
3658 iscsi_tcp_exit(void)
3659 {
3660 iscsi_unregister_transport(&iscsi_tcp_transport);
3661 kmem_cache_destroy(taskcache);
3662 }
3663
3664 module_init(iscsi_tcp_init);
3665 module_exit(iscsi_tcp_exit);
USB Experimental Work