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[SCSI] iscsi: add transport end point callbacks
[net-next-2.6.git] / drivers / scsi / libiscsi.c
CommitLineData
7996a778
MC		 1/*
2 * iSCSI lib functions
3 *
4 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
5 * Copyright (C) 2004 - 2006 Mike Christie
6 * Copyright (C) 2004 - 2005 Dmitry Yusupov
7 * Copyright (C) 2004 - 2005 Alex Aizman
8 * maintained by open-iscsi@googlegroups.com
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 */
24#include <linux/types.h>
25#include <linux/mutex.h>
26#include <linux/kfifo.h>
27#include <linux/delay.h>
28#include <net/tcp.h>
29#include <scsi/scsi_cmnd.h>
30#include <scsi/scsi_device.h>
31#include <scsi/scsi_eh.h>
32#include <scsi/scsi_tcq.h>
33#include <scsi/scsi_host.h>
34#include <scsi/scsi.h>
35#include <scsi/iscsi_proto.h>
36#include <scsi/scsi_transport.h>
37#include <scsi/scsi_transport_iscsi.h>
38#include <scsi/libiscsi.h>
39
40struct iscsi_session *
41class_to_transport_session(struct iscsi_cls_session *cls_session)
42{
43 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
44 return iscsi_hostdata(shost->hostdata);
45}
46EXPORT_SYMBOL_GPL(class_to_transport_session);
47
48#define INVALID_SN_DELTA 0xffff
49
50int
51iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
52{
53 uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
54 uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
55
56 if (max_cmdsn < exp_cmdsn -1 &&
57 max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
58 return ISCSI_ERR_MAX_CMDSN;
59 if (max_cmdsn > session->max_cmdsn ||
60 max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
61 session->max_cmdsn = max_cmdsn;
62 if (exp_cmdsn > session->exp_cmdsn ||
63 exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
64 session->exp_cmdsn = exp_cmdsn;
65
66 return 0;
67}
68EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn);
69
70void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask,
71 struct iscsi_data *hdr,
72 int transport_data_cnt)
73{
74 struct iscsi_conn *conn = ctask->conn;
75
76 memset(hdr, 0, sizeof(struct iscsi_data));
77 hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
78 hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
79 ctask->unsol_datasn++;
80 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
81 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
82
83 hdr->itt = ctask->hdr->itt;
84 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
85
86 hdr->offset = cpu_to_be32(ctask->total_length -
87 transport_data_cnt -
88 ctask->unsol_count);
89
90 if (ctask->unsol_count > conn->max_xmit_dlength) {
91 hton24(hdr->dlength, conn->max_xmit_dlength);
92 ctask->data_count = conn->max_xmit_dlength;
93 hdr->flags = 0;
94 } else {
95 hton24(hdr->dlength, ctask->unsol_count);
96 ctask->data_count = ctask->unsol_count;
97 hdr->flags = ISCSI_FLAG_CMD_FINAL;
98 }
99}
100EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu);
101
102/**
103 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
104 * @ctask: iscsi cmd task
105 *
106 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
107 * fields like dlength or final based on how much data it sends
108 */
109static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
110{
111 struct iscsi_conn *conn = ctask->conn;
112 struct iscsi_session *session = conn->session;
113 struct iscsi_cmd *hdr = ctask->hdr;
114 struct scsi_cmnd *sc = ctask->sc;
115
116 hdr->opcode = ISCSI_OP_SCSI_CMD;
117 hdr->flags = ISCSI_ATTR_SIMPLE;
118 int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
119 hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) |
120 (session->age << ISCSI_AGE_SHIFT);
121 hdr->data_length = cpu_to_be32(sc->request_bufflen);
122 hdr->cmdsn = cpu_to_be32(session->cmdsn);
123 session->cmdsn++;
124 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
125 memcpy(hdr->cdb, sc->cmnd, sc->cmd_len);
126 memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
127
128 if (sc->sc_data_direction == DMA_TO_DEVICE) {
129 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
130 /*
131 * Write counters:
132 *
133 * imm_count bytes to be sent right after
134 * SCSI PDU Header
135 *
136 * unsol_count bytes(as Data-Out) to be sent
137 * without R2T ack right after
138 * immediate data
139 *
140 * r2t_data_count bytes to be sent via R2T ack's
141 *
142 * pad_count bytes to be sent as zero-padding
143 */
144 ctask->imm_count = 0;
145 ctask->unsol_count = 0;
146 ctask->unsol_datasn = 0;
147
148 if (session->imm_data_en) {
149 if (ctask->total_length >= session->first_burst)
150 ctask->imm_count = min(session->first_burst,
151 conn->max_xmit_dlength);
152 else
153 ctask->imm_count = min(ctask->total_length,
154 conn->max_xmit_dlength);
155 hton24(ctask->hdr->dlength, ctask->imm_count);
156 } else
157 zero_data(ctask->hdr->dlength);
158
159 if (!session->initial_r2t_en)
160 ctask->unsol_count = min(session->first_burst,
161 ctask->total_length) - ctask->imm_count;
162 if (!ctask->unsol_count)
163 /* No unsolicit Data-Out's */
164 ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL;
165 } else {
166 ctask->datasn = 0;
167 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
168 zero_data(hdr->dlength);
169
170 if (sc->sc_data_direction == DMA_FROM_DEVICE)
171 hdr->flags |= ISCSI_FLAG_CMD_READ;
172 }
173
174 conn->scsicmd_pdus_cnt++;
175}
176EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu);
177
178/**
179 * iscsi_complete_command - return command back to scsi-ml
180 * @session: iscsi session
181 * @ctask: iscsi cmd task
182 *
183 * Must be called with session lock.
184 * This function returns the scsi command to scsi-ml and returns
185 * the cmd task to the pool of available cmd tasks.
186 */
187static void iscsi_complete_command(struct iscsi_session *session,
188 struct iscsi_cmd_task *ctask)
189{
190 struct scsi_cmnd *sc = ctask->sc;
191
192 ctask->sc = NULL;
193 list_del_init(&ctask->running);
194 __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
195 sc->scsi_done(sc);
196}
197
198/**
199 * iscsi_cmd_rsp - SCSI Command Response processing
200 * @conn: iscsi connection
201 * @hdr: iscsi header
202 * @ctask: scsi command task
203 * @data: cmd data buffer
204 * @datalen: len of buffer
205 *
206 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
207 * then completes the command and task.
208 **/
209static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
210 struct iscsi_cmd_task *ctask, char *data,
211 int datalen)
212{
213 int rc;
214 struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr;
215 struct iscsi_session *session = conn->session;
216 struct scsi_cmnd *sc = ctask->sc;
217
218 rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
219 if (rc) {
220 sc->result = DID_ERROR << 16;
221 goto out;
222 }
223
224 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
225
226 sc->result = (DID_OK << 16) | rhdr->cmd_status;
227
228 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
229 sc->result = DID_ERROR << 16;
230 goto out;
231 }
232
233 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
234 int senselen;
235
236 if (datalen < 2) {
237invalid_datalen:
238 printk(KERN_ERR "Got CHECK_CONDITION but invalid "
239 "data buffer size of %d\n", datalen);
240 sc->result = DID_BAD_TARGET << 16;
241 goto out;
242 }
243
244 senselen = (data[0] << 8) | data[1];
245 if (datalen < senselen)
246 goto invalid_datalen;
247
248 memcpy(sc->sense_buffer, data + 2,
249 min(senselen, SCSI_SENSE_BUFFERSIZE));
250 debug_scsi("copied %d bytes of sense\n",
251 min(senselen, SCSI_SENSE_BUFFERSIZE));
252 }
253
254 if (sc->sc_data_direction == DMA_TO_DEVICE)
255 goto out;
256
257 if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
258 int res_count = be32_to_cpu(rhdr->residual_count);
259
260 if (res_count > 0 && res_count <= sc->request_bufflen)
261 sc->resid = res_count;
262 else
263 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
264 } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
265 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
266 else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
267 sc->resid = be32_to_cpu(rhdr->residual_count);
268
269out:
270 debug_scsi("done [sc %lx res %d itt 0x%x]\n",
271 (long)sc, sc->result, ctask->itt);
272 conn->scsirsp_pdus_cnt++;
273
274 iscsi_complete_command(conn->session, ctask);
275 return rc;
276}
277
278/**
279 * __iscsi_complete_pdu - complete pdu
280 * @conn: iscsi conn
281 * @hdr: iscsi header
282 * @data: data buffer
283 * @datalen: len of data buffer
284 *
285 * Completes pdu processing by freeing any resources allocated at
286 * queuecommand or send generic. session lock must be held and verify
287 * itt must have been called.
288 */
289int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
290 char *data, int datalen)
291{
292 struct iscsi_session *session = conn->session;
293 int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
294 struct iscsi_cmd_task *ctask;
295 struct iscsi_mgmt_task *mtask;
296 uint32_t itt;
297
298 if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG))
299 itt = hdr->itt & ISCSI_ITT_MASK;
300 else
301 itt = hdr->itt;
302
303 if (itt < session->cmds_max) {
304 ctask = session->cmds[itt];
305
306 debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n",
307 opcode, conn->id, ctask->itt, datalen);
308
309 switch(opcode) {
310 case ISCSI_OP_SCSI_CMD_RSP:
311 BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
312 rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data,
313 datalen);
314 break;
315 case ISCSI_OP_SCSI_DATA_IN:
316 BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
317 if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
318 conn->scsirsp_pdus_cnt++;
319 iscsi_complete_command(session, ctask);
320 }
321 break;
322 case ISCSI_OP_R2T:
323 /* LLD handles this for now */
324 break;
325 default:
326 rc = ISCSI_ERR_BAD_OPCODE;
327 break;
328 }
329 } else if (itt >= ISCSI_MGMT_ITT_OFFSET &&
330 itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) {
331 mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET];
332
333 debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
334 opcode, conn->id, mtask->itt, datalen);
335
336 switch(opcode) {
337 case ISCSI_OP_LOGIN_RSP:
338 case ISCSI_OP_TEXT_RSP:
339 case ISCSI_OP_LOGOUT_RSP:
340 rc = iscsi_check_assign_cmdsn(session,
341 (struct iscsi_nopin*)hdr);
342 if (rc)
343 break;
344
345 rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
346 list_del(&mtask->running);
347 if (conn->login_mtask != mtask)
348 __kfifo_put(session->mgmtpool.queue,
349 (void*)&mtask, sizeof(void*));
350 break;
351 case ISCSI_OP_SCSI_TMFUNC_RSP:
352 rc = iscsi_check_assign_cmdsn(session,
353 (struct iscsi_nopin*)hdr);
354 if (rc)
355 break;
356
357 if (datalen) {
358 rc = ISCSI_ERR_PROTO;
359 break;
360 }
361 conn->tmfrsp_pdus_cnt++;
362 if (conn->tmabort_state == TMABORT_INITIAL) {
363 conn->tmabort_state =
364 ((struct iscsi_tm_rsp *)hdr)->
365 response == ISCSI_TMF_RSP_COMPLETE ?
366 TMABORT_SUCCESS:TMABORT_FAILED;
367 /* unblock eh_abort() */
368 wake_up(&conn->ehwait);
369 }
370 break;
371 case ISCSI_OP_NOOP_IN:
372 if (hdr->ttt != ISCSI_RESERVED_TAG) {
373 rc = ISCSI_ERR_PROTO;
374 break;
375 }
376 rc = iscsi_check_assign_cmdsn(session,
377 (struct iscsi_nopin*)hdr);
378 if (rc)
379 break;
380 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
381
382 rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen);
383 list_del(&mtask->running);
384 if (conn->login_mtask != mtask)
385 __kfifo_put(session->mgmtpool.queue,
386 (void*)&mtask, sizeof(void*));
387 break;
388 default:
389 rc = ISCSI_ERR_BAD_OPCODE;
390 break;
391 }
392 } else if (itt == ISCSI_RESERVED_TAG) {
393 switch(opcode) {
394 case ISCSI_OP_NOOP_IN:
395 if (!datalen) {
396 rc = iscsi_check_assign_cmdsn(session,
397 (struct iscsi_nopin*)hdr);
398 if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
399 rc = iscsi_recv_pdu(conn->cls_conn,
400 hdr, NULL, 0);
401 } else
402 rc = ISCSI_ERR_PROTO;
403 break;
404 case ISCSI_OP_REJECT:
405 /* we need sth like iscsi_reject_rsp()*/
406 case ISCSI_OP_ASYNC_EVENT:
407 /* we need sth like iscsi_async_event_rsp() */
408 rc = ISCSI_ERR_BAD_OPCODE;
409 break;
410 default:
411 rc = ISCSI_ERR_BAD_OPCODE;
412 break;
413 }
414 } else
415 rc = ISCSI_ERR_BAD_ITT;
416
417 return rc;
418}
419EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
420
421int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
422 char *data, int datalen)
423{
424 int rc;
425
426 spin_lock(&conn->session->lock);
427 rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
428 spin_unlock(&conn->session->lock);
429 return rc;
430}
431EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
432
433/* verify itt (itt encoding: age+cid+itt) */
434int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
435 uint32_t *ret_itt)
436{
437 struct iscsi_session *session = conn->session;
438 struct iscsi_cmd_task *ctask;
439 uint32_t itt;
440
441 if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
442 if ((hdr->itt & ISCSI_AGE_MASK) !=
443 (session->age << ISCSI_AGE_SHIFT)) {
444 printk(KERN_ERR "iscsi_tcp: received itt %x expected "
445 "session age (%x)\n", hdr->itt,
446 session->age & ISCSI_AGE_MASK);
447 return ISCSI_ERR_BAD_ITT;
448 }
449
450 if ((hdr->itt & ISCSI_CID_MASK) !=
451 (conn->id << ISCSI_CID_SHIFT)) {
452 printk(KERN_ERR "iscsi_tcp: received itt %x, expected "
453 "CID (%x)\n", hdr->itt, conn->id);
454 return ISCSI_ERR_BAD_ITT;
455 }
456 itt = hdr->itt & ISCSI_ITT_MASK;
457 } else
458 itt = hdr->itt;
459
460 if (itt < session->cmds_max) {
461 ctask = session->cmds[itt];
462
463 if (!ctask->sc) {
464 printk(KERN_INFO "iscsi_tcp: dropping ctask with "
465 "itt 0x%x\n", ctask->itt);
466 /* force drop */
467 return ISCSI_ERR_NO_SCSI_CMD;
468 }
469
470 if (ctask->sc->SCp.phase != session->age) {
471 printk(KERN_ERR "iscsi_tcp: ctask's session age %d, "
472 "expected %d\n", ctask->sc->SCp.phase,
473 session->age);
474 return ISCSI_ERR_SESSION_FAILED;
475 }
476 }
477
478 *ret_itt = itt;
479 return 0;
480}
481EXPORT_SYMBOL_GPL(iscsi_verify_itt);
482
483void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
484{
485 struct iscsi_session *session = conn->session;
486 unsigned long flags;
487
488 spin_lock_irqsave(&session->lock, flags);
489 if (session->conn_cnt == 1 || session->leadconn == conn)
490 session->state = ISCSI_STATE_FAILED;
491 spin_unlock_irqrestore(&session->lock, flags);
492 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
493 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
494 iscsi_conn_error(conn->cls_conn, err);
495}
496EXPORT_SYMBOL_GPL(iscsi_conn_failure);
497
498/**
499 * iscsi_data_xmit - xmit any command into the scheduled connection
500 * @conn: iscsi connection
501 *
502 * Notes:
503 * The function can return -EAGAIN in which case the caller must
504 * re-schedule it again later or recover. '0' return code means
505 * successful xmit.
506 **/
507static int iscsi_data_xmit(struct iscsi_conn *conn)
508{
509 struct iscsi_transport *tt;
510
511 if (unlikely(conn->suspend_tx)) {
512 debug_scsi("conn %d Tx suspended!\n", conn->id);
513 return 0;
514 }
515 tt = conn->session->tt;
516
517 /*
518 * Transmit in the following order:
519 *
520 * 1) un-finished xmit (ctask or mtask)
521 * 2) immediate control PDUs
522 * 3) write data
523 * 4) SCSI commands
524 * 5) non-immediate control PDUs
525 *
526 * No need to lock around __kfifo_get as long as
527 * there's one producer and one consumer.
528 */
529
530 BUG_ON(conn->ctask && conn->mtask);
531
532 if (conn->ctask) {
533 if (tt->xmit_cmd_task(conn, conn->ctask))
534 goto again;
535 /* done with this in-progress ctask */
536 conn->ctask = NULL;
537 }
538 if (conn->mtask) {
539 if (tt->xmit_mgmt_task(conn, conn->mtask))
540 goto again;
541 /* done with this in-progress mtask */
542 conn->mtask = NULL;
543 }
544
545 /* process immediate first */
546 if (unlikely(__kfifo_len(conn->immqueue))) {
547 while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
548 sizeof(void*))) {
549 list_add_tail(&conn->mtask->running,
550 &conn->mgmt_run_list);
551 if (tt->xmit_mgmt_task(conn, conn->mtask))
552 goto again;
553 }
554 /* done with this mtask */
555 conn->mtask = NULL;
556 }
557
558 /* process command queue */
559 while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
560 sizeof(void*))) {
561 /*
562 * iscsi tcp may readd the task to the xmitqueue to send
563 * write data
564 */
565 if (list_empty(&conn->ctask->running))
566 list_add_tail(&conn->ctask->running, &conn->run_list);
567 if (tt->xmit_cmd_task(conn, conn->ctask))
568 goto again;
569 }
570 /* done with this ctask */
571 conn->ctask = NULL;
572
573 /* process the rest control plane PDUs, if any */
574 if (unlikely(__kfifo_len(conn->mgmtqueue))) {
575 while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
576 sizeof(void*))) {
577 list_add_tail(&conn->mtask->running,
578 &conn->mgmt_run_list);
579 if (tt->xmit_mgmt_task(conn, conn->mtask))
580 goto again;
581 }
582 /* done with this mtask */
583 conn->mtask = NULL;
584 }
585
586 return 0;
587
588again:
589 if (unlikely(conn->suspend_tx))
590 return 0;
591
592 return -EAGAIN;
593}
594
595static void iscsi_xmitworker(void *data)
596{
597 struct iscsi_conn *conn = data;
598
599 /*
600 * serialize Xmit worker on a per-connection basis.
601 */
602 mutex_lock(&conn->xmitmutex);
603 if (iscsi_data_xmit(conn))
604 scsi_queue_work(conn->session->host, &conn->xmitwork);
605 mutex_unlock(&conn->xmitmutex);
606}
607
608enum {
609 FAILURE_BAD_HOST = 1,
610 FAILURE_SESSION_FAILED,
611 FAILURE_SESSION_FREED,
612 FAILURE_WINDOW_CLOSED,
613 FAILURE_SESSION_TERMINATE,
614 FAILURE_SESSION_RECOVERY_TIMEOUT,
615};
616
617int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
618{
619 struct Scsi_Host *host;
620 int reason = 0;
621 struct iscsi_session *session;
622 struct iscsi_conn *conn;
623 struct iscsi_cmd_task *ctask = NULL;
624
625 sc->scsi_done = done;
626 sc->result = 0;
627
628 host = sc->device->host;
629 session = iscsi_hostdata(host->hostdata);
630
631 spin_lock(&session->lock);
632
633 if (session->state != ISCSI_STATE_LOGGED_IN) {
634 if (session->recovery_failed) {
635 reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
636 goto fault;
637 } else if (session->state == ISCSI_STATE_FAILED) {
638 reason = FAILURE_SESSION_FAILED;
639 goto reject;
640 } else if (session->state == ISCSI_STATE_TERMINATE) {
641 reason = FAILURE_SESSION_TERMINATE;
642 goto fault;
643 }
644 reason = FAILURE_SESSION_FREED;
645 goto fault;
646 }
647
648 /*
649 * Check for iSCSI window and take care of CmdSN wrap-around
650 */
651 if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
652 reason = FAILURE_WINDOW_CLOSED;
653 goto reject;
654 }
655
656 conn = session->leadconn;
657
658 __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
659 sc->SCp.phase = session->age;
660 sc->SCp.ptr = (char *)ctask;
661
662 ctask->mtask = NULL;
663 ctask->conn = conn;
664 ctask->sc = sc;
665 INIT_LIST_HEAD(&ctask->running);
666 ctask->total_length = sc->request_bufflen;
667 iscsi_prep_scsi_cmd_pdu(ctask);
668
669 session->tt->init_cmd_task(ctask);
670
671 __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
672 debug_scsi(
673 "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
674 sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
675 conn->id, (long)sc, ctask->itt, sc->request_bufflen,
676 session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
677 spin_unlock(&session->lock);
678
679 scsi_queue_work(host, &conn->xmitwork);
680 return 0;
681
682reject:
683 spin_unlock(&session->lock);
684 debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
685 return SCSI_MLQUEUE_HOST_BUSY;
686
687fault:
688 spin_unlock(&session->lock);
689 printk(KERN_ERR "iscsi_tcp: cmd 0x%x is not queued (%d)\n",
690 sc->cmnd[0], reason);
691 sc->result = (DID_NO_CONNECT << 16);
692 sc->resid = sc->request_bufflen;
693 sc->scsi_done(sc);
694 return 0;
695}
696EXPORT_SYMBOL_GPL(iscsi_queuecommand);
697
698int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
699{
700 if (depth > ISCSI_MAX_CMD_PER_LUN)
701 depth = ISCSI_MAX_CMD_PER_LUN;
702 scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
703 return sdev->queue_depth;
704}
705EXPORT_SYMBOL_GPL(iscsi_change_queue_depth);
706
707static int
708iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
709 char *data, uint32_t data_size)
710{
711 struct iscsi_session *session = conn->session;
712 struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
713 struct iscsi_mgmt_task *mtask;
714
715 spin_lock_bh(&session->lock);
716 if (session->state == ISCSI_STATE_TERMINATE) {
717 spin_unlock_bh(&session->lock);
718 return -EPERM;
719 }
720 if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
721 hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
722 /*
723 * Login and Text are sent serially, in
724 * request-followed-by-response sequence.
725 * Same mtask can be used. Same ITT must be used.
726 * Note that login_mtask is preallocated at conn_create().
727 */
728 mtask = conn->login_mtask;
729 else {
730 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
731 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
732
733 if (!__kfifo_get(session->mgmtpool.queue,
734 (void*)&mtask, sizeof(void*))) {
735 spin_unlock_bh(&session->lock);
736 return -ENOSPC;
737 }
738 }
739
740 /*
741 * pre-format CmdSN and ExpStatSN for outgoing PDU.
742 */
743 if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
744 hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) |
745 (session->age << ISCSI_AGE_SHIFT);
746 nop->cmdsn = cpu_to_be32(session->cmdsn);
747 if (conn->c_stage == ISCSI_CONN_STARTED &&
748 !(hdr->opcode & ISCSI_OP_IMMEDIATE))
749 session->cmdsn++;
750 } else
751 /* do not advance CmdSN */
752 nop->cmdsn = cpu_to_be32(session->cmdsn);
753
754 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
755
756 if (data_size) {
757 memcpy(mtask->data, data, data_size);
758 mtask->data_count = data_size;
759 } else
760 mtask->data_count = 0;
761
762 INIT_LIST_HEAD(&mtask->running);
763 memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr));
764 if (session->tt->init_mgmt_task)
765 session->tt->init_mgmt_task(conn, mtask, data, data_size);
766 spin_unlock_bh(&session->lock);
767
768 debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
769 hdr->opcode, hdr->itt, data_size);
770
771 /*
772 * since send_pdu() could be called at least from two contexts,
773 * we need to serialize __kfifo_put, so we don't have to take
774 * additional lock on fast data-path
775 */
776 if (hdr->opcode & ISCSI_OP_IMMEDIATE)
777 __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
778 else
779 __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
780
781 scsi_queue_work(session->host, &conn->xmitwork);
782 return 0;
783}
784
785int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
786 char *data, uint32_t data_size)
787{
788 struct iscsi_conn *conn = cls_conn->dd_data;
789 int rc;
790
791 mutex_lock(&conn->xmitmutex);
792 rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
793 mutex_unlock(&conn->xmitmutex);
794
795 return rc;
796}
797EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
798
799void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
800{
801 struct iscsi_session *session = class_to_transport_session(cls_session);
802 struct iscsi_conn *conn = session->leadconn;
803
804 spin_lock_bh(&session->lock);
805 if (session->state != ISCSI_STATE_LOGGED_IN) {
806 session->recovery_failed = 1;
807 if (conn)
808 wake_up(&conn->ehwait);
809 }
810 spin_unlock_bh(&session->lock);
811}
812EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
813
814int iscsi_eh_host_reset(struct scsi_cmnd *sc)
815{
816 struct Scsi_Host *host = sc->device->host;
817 struct iscsi_session *session = iscsi_hostdata(host->hostdata);
818 struct iscsi_conn *conn = session->leadconn;
819 int fail_session = 0;
820
821 spin_lock_bh(&session->lock);
822 if (session->state == ISCSI_STATE_TERMINATE) {
823failed:
824 debug_scsi("failing host reset: session terminated "
825 "[CID %d age %d]", conn->id, session->age);
826 spin_unlock_bh(&session->lock);
827 return FAILED;
828 }
829
830 if (sc->SCp.phase == session->age) {
831 debug_scsi("failing connection CID %d due to SCSI host reset",
832 conn->id);
833 fail_session = 1;
834 }
835 spin_unlock_bh(&session->lock);
836
837 /*
838 * we drop the lock here but the leadconn cannot be destoyed while
839 * we are in the scsi eh
840 */
841 if (fail_session) {
842 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
843 /*
844 * if userspace cannot respond then we must kick this off
845 * here for it
846 */
847 iscsi_start_session_recovery(session, conn, STOP_CONN_RECOVER);
848 }
849
850 debug_scsi("iscsi_eh_host_reset wait for relogin\n");
851 wait_event_interruptible(conn->ehwait,
852 session->state == ISCSI_STATE_TERMINATE ||
853 session->state == ISCSI_STATE_LOGGED_IN ||
854 session->recovery_failed);
855 if (signal_pending(current))
856 flush_signals(current);
857
858 spin_lock_bh(&session->lock);
859 if (session->state == ISCSI_STATE_LOGGED_IN)
860 printk(KERN_INFO "host reset succeeded\n");
861 else
862 goto failed;
863 spin_unlock_bh(&session->lock);
864
865 return SUCCESS;
866}
867EXPORT_SYMBOL_GPL(iscsi_eh_host_reset);
868
869static void iscsi_tmabort_timedout(unsigned long data)
870{
871 struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
872 struct iscsi_conn *conn = ctask->conn;
873 struct iscsi_session *session = conn->session;
874
875 spin_lock(&session->lock);
876 if (conn->tmabort_state == TMABORT_INITIAL) {
877 conn->tmabort_state = TMABORT_TIMEDOUT;
878 debug_scsi("tmabort timedout [sc %p itt 0x%x]\n",
879 ctask->sc, ctask->itt);
880 /* unblock eh_abort() */
881 wake_up(&conn->ehwait);
882 }
883 spin_unlock(&session->lock);
884}
885
886/* must be called with the mutex lock */
887static int iscsi_exec_abort_task(struct scsi_cmnd *sc,
888 struct iscsi_cmd_task *ctask)
889{
890 struct iscsi_conn *conn = ctask->conn;
891 struct iscsi_session *session = conn->session;
892 struct iscsi_tm *hdr = &conn->tmhdr;
893 int rc;
894
895 /*
896 * ctask timed out but session is OK requests must be serialized.
897 */
898 memset(hdr, 0, sizeof(struct iscsi_tm));
899 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
900 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
901 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
902 memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
903 hdr->rtt = ctask->hdr->itt;
904 hdr->refcmdsn = ctask->hdr->cmdsn;
905
906 rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
907 NULL, 0);
908 if (rc) {
909 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
910 debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc);
911 return rc;
912 }
913
914 debug_scsi("abort sent [itt 0x%x]\n", ctask->itt);
915
916 spin_lock_bh(&session->lock);
917 ctask->mtask = (struct iscsi_mgmt_task *)
918 session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) -
919 ISCSI_MGMT_ITT_OFFSET];
920
921 if (conn->tmabort_state == TMABORT_INITIAL) {
922 conn->tmfcmd_pdus_cnt++;
923 conn->tmabort_timer.expires = 10*HZ + jiffies;
924 conn->tmabort_timer.function = iscsi_tmabort_timedout;
925 conn->tmabort_timer.data = (unsigned long)ctask;
926 add_timer(&conn->tmabort_timer);
927 debug_scsi("abort set timeout [itt 0x%x]", ctask->itt);
928 }
929 spin_unlock_bh(&session->lock);
930 mutex_unlock(&conn->xmitmutex);
931
932 /*
933 * block eh thread until:
934 *
935 * 1) abort response
936 * 2) abort timeout
937 * 3) session is terminated or restarted or userspace has
938 * given up on recovery
939 */
940 wait_event_interruptible(conn->ehwait,
941 sc->SCp.phase != session->age ||
942 session->state != ISCSI_STATE_LOGGED_IN ||
943 conn->tmabort_state != TMABORT_INITIAL ||
944 session->recovery_failed);
945 if (signal_pending(current))
946 flush_signals(current);
947 del_timer_sync(&conn->tmabort_timer);
948
949 mutex_lock(&conn->xmitmutex);
950 return 0;
951}
952
953/*
954 * xmit mutex and session lock must be held
955 */
956#define iscsi_remove_task(tasktype) \
957static struct iscsi_##tasktype * \
958iscsi_remove_##tasktype(struct kfifo *fifo, uint32_t itt) \
959{ \
960 int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*); \
961 struct iscsi_##tasktype *task; \
962 \
963 debug_scsi("searching %d tasks\n", nr_tasks); \
964 \
965 for (i = 0; i < nr_tasks; i++) { \
966 __kfifo_get(fifo, (void*)&task, sizeof(void*)); \
967 debug_scsi("check task %u\n", task->itt); \
968 \
969 if (task->itt == itt) { \
970 debug_scsi("matched task\n"); \
971 break; \
972 } \
973 \
974 __kfifo_put(fifo, (void*)&task, sizeof(void*)); \
975 } \
976 return NULL; \
977}
978
979iscsi_remove_task(mgmt_task);
980iscsi_remove_task(cmd_task);
981
982static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask)
983{
984 struct iscsi_conn *conn = ctask->conn;
985 struct iscsi_session *session = conn->session;
986
987 if (!ctask->mtask)
988 return -EINVAL;
989
990 if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt))
991 list_del(&ctask->mtask->running);
992 __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask,
993 sizeof(void*));
994 ctask->mtask = NULL;
995 return 0;
996}
997
998/*
999 * session lock and xmitmutex must be held
1000 */
1001static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
1002 int err)
1003{
1004 struct scsi_cmnd *sc;
1005
1006 conn->session->tt->cleanup_cmd_task(conn, ctask);
1007 iscsi_ctask_mtask_cleanup(ctask);
1008
1009 sc = ctask->sc;
1010 if (!sc)
1011 return;
1012 sc->result = err;
1013 sc->resid = sc->request_bufflen;
1014 iscsi_complete_command(conn->session, ctask);
1015}
1016
1017int iscsi_eh_abort(struct scsi_cmnd *sc)
1018{
1019 struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
1020 struct iscsi_conn *conn = ctask->conn;
1021 struct iscsi_session *session = conn->session;
1022 struct iscsi_cmd_task *pending_ctask;
1023 int rc;
1024
1025 conn->eh_abort_cnt++;
1026 debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt);
1027
1028 mutex_lock(&conn->xmitmutex);
1029 spin_lock_bh(&session->lock);
1030
1031 /*
1032 * If we are not logged in or we have started a new session
1033 * then let the host reset code handle this
1034 */
1035 if (session->state != ISCSI_STATE_LOGGED_IN ||
1036 sc->SCp.phase != session->age)
1037 goto failed;
1038
1039 /* ctask completed before time out */
1040 if (!ctask->sc)
1041 goto success;
1042
1043 /* what should we do here ? */
1044 if (conn->ctask == ctask) {
1045 printk(KERN_INFO "sc %p itt 0x%x partially sent. Failing "
1046 "abort\n", sc, ctask->itt);
1047 goto failed;
1048 }
1049
1050 /* check for the easy pending cmd abort */
1051 pending_ctask = iscsi_remove_cmd_task(conn->xmitqueue, ctask->itt);
1052 if (pending_ctask) {
1053 /* iscsi_tcp queues write transfers on the xmitqueue */
1054 if (list_empty(&pending_ctask->running)) {
1055 debug_scsi("found pending task\n");
1056 goto success;
1057 } else
1058 __kfifo_put(conn->xmitqueue, (void*)&pending_ctask,
1059 sizeof(void*));
1060 }
1061
1062 conn->tmabort_state = TMABORT_INITIAL;
1063
1064 spin_unlock_bh(&session->lock);
1065 rc = iscsi_exec_abort_task(sc, ctask);
1066 spin_lock_bh(&session->lock);
1067
1068 iscsi_ctask_mtask_cleanup(ctask);
1069 if (rc || sc->SCp.phase != session->age ||
1070 session->state != ISCSI_STATE_LOGGED_IN)
1071 goto failed;
1072
1073 /* ctask completed before tmf abort response */
1074 if (!ctask->sc) {
1075 debug_scsi("sc completed while abort in progress\n");
1076 goto success;
1077 }
1078
1079 if (conn->tmabort_state != TMABORT_SUCCESS) {
1080 spin_unlock_bh(&session->lock);
1081 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1082 spin_lock_bh(&session->lock);
1083 goto failed;
1084 }
1085
1086success:
1087 debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1088 spin_unlock_bh(&session->lock);
1089
1090 /*
1091 * clean up task if aborted. we have the xmitmutex so grab
1092 * the recv lock as a writer
1093 */
1094 write_lock_bh(conn->recv_lock);
1095 spin_lock(&session->lock);
1096 fail_command(conn, ctask, DID_ABORT << 16);
1097 spin_unlock(&session->lock);
1098 write_unlock_bh(conn->recv_lock);
1099
1100 mutex_unlock(&conn->xmitmutex);
1101 return SUCCESS;
1102
1103failed:
1104 spin_unlock_bh(&session->lock);
1105 mutex_unlock(&conn->xmitmutex);
1106
1107 debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
1108 return FAILED;
1109}
1110EXPORT_SYMBOL_GPL(iscsi_eh_abort);
1111
1112int
1113iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
1114{
1115 int i;
1116
1117 *items = kmalloc(max * sizeof(void*), GFP_KERNEL);
1118 if (*items == NULL)
1119 return -ENOMEM;
1120
1121 q->max = max;
1122 q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
1123 if (q->pool == NULL) {
1124 kfree(*items);
1125 return -ENOMEM;
1126 }
1127
1128 q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
1129 GFP_KERNEL, NULL);
1130 if (q->queue == ERR_PTR(-ENOMEM)) {
1131 kfree(q->pool);
1132 kfree(*items);
1133 return -ENOMEM;
1134 }
1135
1136 for (i = 0; i < max; i++) {
1137 q->pool[i] = kmalloc(item_size, GFP_KERNEL);
1138 if (q->pool[i] == NULL) {
1139 int j;
1140
1141 for (j = 0; j < i; j++)
1142 kfree(q->pool[j]);
1143
1144 kfifo_free(q->queue);
1145 kfree(q->pool);
1146 kfree(*items);
1147 return -ENOMEM;
1148 }
1149 memset(q->pool[i], 0, item_size);
1150 (*items)[i] = q->pool[i];
1151 __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
1152 }
1153 return 0;
1154}
1155EXPORT_SYMBOL_GPL(iscsi_pool_init);
1156
1157void iscsi_pool_free(struct iscsi_queue *q, void **items)
1158{
1159 int i;
1160
1161 for (i = 0; i < q->max; i++)
1162 kfree(items[i]);
1163 kfree(q->pool);
1164 kfree(items);
1165}
1166EXPORT_SYMBOL_GPL(iscsi_pool_free);
1167
1168/*
1169 * iSCSI Session's hostdata organization:
1170 *
1171 * *------------------* <== hostdata_session(host->hostdata)
1172 * | ptr to class sess|
1173 * |------------------| <== iscsi_hostdata(host->hostdata)
1174 * | iscsi_session |
1175 * *------------------*
1176 */
1177
1178#define hostdata_privsize(_sz) (sizeof(unsigned long) + _sz + \
1179 _sz % sizeof(unsigned long))
1180
1181#define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata))
1182
1183/**
1184 * iscsi_session_setup - create iscsi cls session and host and session
1185 * @scsit: scsi transport template
1186 * @iscsit: iscsi transport template
1187 * @initial_cmdsn: initial CmdSN
1188 * @hostno: host no allocated
1189 *
1190 * This can be used by software iscsi_transports that allocate
1191 * a session per scsi host.
1192 **/
1193struct iscsi_cls_session *
1194iscsi_session_setup(struct iscsi_transport *iscsit,
1195 struct scsi_transport_template *scsit,
1196 int cmd_task_size, int mgmt_task_size,
1197 uint32_t initial_cmdsn, uint32_t *hostno)
1198{
1199 struct Scsi_Host *shost;
1200 struct iscsi_session *session;
1201 struct iscsi_cls_session *cls_session;
1202 int cmd_i;
1203
1204 shost = scsi_host_alloc(iscsit->host_template,
1205 hostdata_privsize(sizeof(*session)));
1206 if (!shost)
1207 return NULL;
1208
1209 shost->max_id = 1;
1210 shost->max_channel = 0;
1211 shost->max_lun = iscsit->max_lun;
1212 shost->max_cmd_len = iscsit->max_cmd_len;
1213 shost->transportt = scsit;
1214 shost->transportt->create_work_queue = 1;
1215 *hostno = shost->host_no;
1216
1217 session = iscsi_hostdata(shost->hostdata);
1218 memset(session, 0, sizeof(struct iscsi_session));
1219 session->host = shost;
1220 session->state = ISCSI_STATE_FREE;
1221 session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
1222 session->cmds_max = ISCSI_XMIT_CMDS_MAX;
1223 session->cmdsn = initial_cmdsn;
1224 session->exp_cmdsn = initial_cmdsn + 1;
1225 session->max_cmdsn = initial_cmdsn + 1;
1226 session->max_r2t = 1;
1227 session->tt = iscsit;
1228
1229 /* initialize SCSI PDU commands pool */
1230 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
1231 (void***)&session->cmds,
1232 cmd_task_size + sizeof(struct iscsi_cmd_task)))
1233 goto cmdpool_alloc_fail;
1234
1235 /* pre-format cmds pool with ITT */
1236 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
1237 struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
1238
1239 if (cmd_task_size)
1240 ctask->dd_data = &ctask[1];
1241 ctask->itt = cmd_i;
1242 }
1243
1244 spin_lock_init(&session->lock);
1245 INIT_LIST_HEAD(&session->connections);
1246
1247 /* initialize immediate command pool */
1248 if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
1249 (void***)&session->mgmt_cmds,
1250 mgmt_task_size + sizeof(struct iscsi_mgmt_task)))
1251 goto mgmtpool_alloc_fail;
1252
1253
1254 /* pre-format immediate cmds pool with ITT */
1255 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
1256 struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
1257
1258 if (mgmt_task_size)
1259 mtask->dd_data = &mtask[1];
1260 mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
1261 mtask->data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH,
1262 GFP_KERNEL);
1263 if (!mtask->data) {
1264 int j;
1265
1266 for (j = 0; j < cmd_i; j++)
1267 kfree(session->mgmt_cmds[j]->data);
1268 goto immdata_alloc_fail;
1269 }
1270 }
1271
1272 if (scsi_add_host(shost, NULL))
1273 goto add_host_fail;
1274
1275 cls_session = iscsi_create_session(shost, iscsit, 0);
1276 if (!cls_session)
1277 goto cls_session_fail;
1278 *(unsigned long*)shost->hostdata = (unsigned long)cls_session;
1279
1280 return cls_session;
1281
1282cls_session_fail:
1283 scsi_remove_host(shost);
1284add_host_fail:
1285 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
1286 kfree(session->mgmt_cmds[cmd_i]->data);
1287immdata_alloc_fail:
1288 iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1289mgmtpool_alloc_fail:
1290 iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1291cmdpool_alloc_fail:
1292 scsi_host_put(shost);
1293 return NULL;
1294}
1295EXPORT_SYMBOL_GPL(iscsi_session_setup);
1296
1297/**
1298 * iscsi_session_teardown - destroy session, host, and cls_session
1299 * shost: scsi host
1300 *
1301 * This can be used by software iscsi_transports that allocate
1302 * a session per scsi host.
1303 **/
1304void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
1305{
1306 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
1307 struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
1308 int cmd_i;
1309
1310 scsi_remove_host(shost);
1311
1312 for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
1313 kfree(session->mgmt_cmds[cmd_i]->data);
1314
1315 iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
1316 iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
1317
1318 iscsi_destroy_session(cls_session);
1319 scsi_host_put(shost);
1320}
1321EXPORT_SYMBOL_GPL(iscsi_session_teardown);
1322
1323/**
1324 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
1325 * @cls_session: iscsi_cls_session
1326 * @conn_idx: cid
1327 **/
1328struct iscsi_cls_conn *
1329iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1330{
1331 struct iscsi_session *session = class_to_transport_session(cls_session);
1332 struct iscsi_conn *conn;
1333 struct iscsi_cls_conn *cls_conn;
1334
1335 cls_conn = iscsi_create_conn(cls_session, conn_idx);
1336 if (!cls_conn)
1337 return NULL;
1338 conn = cls_conn->dd_data;
1339 memset(conn, 0, sizeof(*conn));
1340
1341 conn->session = session;
1342 conn->cls_conn = cls_conn;
1343 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
1344 conn->id = conn_idx;
1345 conn->exp_statsn = 0;
1346 conn->tmabort_state = TMABORT_INITIAL;
1347 INIT_LIST_HEAD(&conn->run_list);
1348 INIT_LIST_HEAD(&conn->mgmt_run_list);
1349
1350 /* initialize general xmit PDU commands queue */
1351 conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
1352 GFP_KERNEL, NULL);
1353 if (conn->xmitqueue == ERR_PTR(-ENOMEM))
1354 goto xmitqueue_alloc_fail;
1355
1356 /* initialize general immediate & non-immediate PDU commands queue */
1357 conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1358 GFP_KERNEL, NULL);
1359 if (conn->immqueue == ERR_PTR(-ENOMEM))
1360 goto immqueue_alloc_fail;
1361
1362 conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
1363 GFP_KERNEL, NULL);
1364 if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
1365 goto mgmtqueue_alloc_fail;
1366
1367 INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
1368
1369 /* allocate login_mtask used for the login/text sequences */
1370 spin_lock_bh(&session->lock);
1371 if (!__kfifo_get(session->mgmtpool.queue,
1372 (void*)&conn->login_mtask,
1373 sizeof(void*))) {
1374 spin_unlock_bh(&session->lock);
1375 goto login_mtask_alloc_fail;
1376 }
1377 spin_unlock_bh(&session->lock);
1378
1379 init_timer(&conn->tmabort_timer);
1380 mutex_init(&conn->xmitmutex);
1381 init_waitqueue_head(&conn->ehwait);
1382
1383 return cls_conn;
1384
1385login_mtask_alloc_fail:
1386 kfifo_free(conn->mgmtqueue);
1387mgmtqueue_alloc_fail:
1388 kfifo_free(conn->immqueue);
1389immqueue_alloc_fail:
1390 kfifo_free(conn->xmitqueue);
1391xmitqueue_alloc_fail:
1392 iscsi_destroy_conn(cls_conn);
1393 return NULL;
1394}
1395EXPORT_SYMBOL_GPL(iscsi_conn_setup);
1396
1397/**
1398 * iscsi_conn_teardown - teardown iscsi connection
1399 * cls_conn: iscsi class connection
1400 *
1401 * TODO: we may need to make this into a two step process
1402 * like scsi-mls remove + put host
1403 */
1404void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
1405{
1406 struct iscsi_conn *conn = cls_conn->dd_data;
1407 struct iscsi_session *session = conn->session;
1408 unsigned long flags;
1409
1410 mutex_lock(&conn->xmitmutex);
1411 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1412 if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE) {
1413 if (session->tt->suspend_conn_recv)
1414 session->tt->suspend_conn_recv(conn);
1415
1416 session->tt->terminate_conn(conn);
1417 }
1418
1419 spin_lock_bh(&session->lock);
1420 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
1421 if (session->leadconn == conn) {
1422 /*
1423 * leading connection? then give up on recovery.
1424 */
1425 session->state = ISCSI_STATE_TERMINATE;
1426 wake_up(&conn->ehwait);
1427 }
1428 spin_unlock_bh(&session->lock);
1429
1430 mutex_unlock(&conn->xmitmutex);
1431
1432 /*
1433 * Block until all in-progress commands for this connection
1434 * time out or fail.
1435 */
1436 for (;;) {
1437 spin_lock_irqsave(session->host->host_lock, flags);
1438 if (!session->host->host_busy) { /* OK for ERL == 0 */
1439 spin_unlock_irqrestore(session->host->host_lock, flags);
1440 break;
1441 }
1442 spin_unlock_irqrestore(session->host->host_lock, flags);
1443 msleep_interruptible(500);
1444 printk("conn_destroy(): host_busy %d host_failed %d\n",
1445 session->host->host_busy, session->host->host_failed);
1446 /*
1447 * force eh_abort() to unblock
1448 */
1449 wake_up(&conn->ehwait);
1450 }
1451
1452 spin_lock_bh(&session->lock);
1453 __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
1454 sizeof(void*));
1455 list_del(&conn->item);
1456 if (list_empty(&session->connections))
1457 session->leadconn = NULL;
1458 if (session->leadconn && session->leadconn == conn)
1459 session->leadconn = container_of(session->connections.next,
1460 struct iscsi_conn, item);
1461
1462 if (session->leadconn == NULL)
1463 /* no connections exits.. reset sequencing */
1464 session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
1465 spin_unlock_bh(&session->lock);
1466
1467 kfifo_free(conn->xmitqueue);
1468 kfifo_free(conn->immqueue);
1469 kfifo_free(conn->mgmtqueue);
1470
1471 iscsi_destroy_conn(cls_conn);
1472}
1473EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
1474
1475int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
1476{
1477 struct iscsi_conn *conn = cls_conn->dd_data;
1478 struct iscsi_session *session = conn->session;
1479
1480 if (session == NULL) {
1481 printk(KERN_ERR "iscsi: can't start unbound connection\n");
1482 return -EPERM;
1483 }
1484
1485 spin_lock_bh(&session->lock);
1486 conn->c_stage = ISCSI_CONN_STARTED;
1487 session->state = ISCSI_STATE_LOGGED_IN;
1488
1489 switch(conn->stop_stage) {
1490 case STOP_CONN_RECOVER:
1491 /*
1492 * unblock eh_abort() if it is blocked. re-try all
1493 * commands after successful recovery
1494 */
1495 session->conn_cnt++;
1496 conn->stop_stage = 0;
1497 conn->tmabort_state = TMABORT_INITIAL;
1498 session->age++;
1499 session->recovery_failed = 0;
1500 spin_unlock_bh(&session->lock);
1501
1502 iscsi_unblock_session(session_to_cls(session));
1503 wake_up(&conn->ehwait);
1504 return 0;
1505 case STOP_CONN_TERM:
1506 session->conn_cnt++;
1507 conn->stop_stage = 0;
1508 break;
1509 case STOP_CONN_SUSPEND:
1510 conn->stop_stage = 0;
1511 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1512 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1513 break;
1514 default:
1515 break;
1516 }
1517 spin_unlock_bh(&session->lock);
1518
1519 return 0;
1520}
1521EXPORT_SYMBOL_GPL(iscsi_conn_start);
1522
1523static void
1524flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
1525{
1526 struct iscsi_mgmt_task *mtask, *tmp;
1527
1528 /* handle pending */
1529 while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) ||
1530 __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) {
1531 if (mtask == conn->login_mtask)
1532 continue;
1533 debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt);
1534 __kfifo_put(session->mgmtpool.queue, (void*)&mtask,
1535 sizeof(void*));
1536 }
1537
1538 /* handle running */
1539 list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) {
1540 debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt);
1541 if (mtask == conn->login_mtask)
1542 continue;
1543 list_del(&mtask->running);
1544 __kfifo_put(session->mgmtpool.queue, (void*)&conn->mtask,
1545 sizeof(void*));
1546 }
1547
1548 conn->mtask = NULL;
1549}
1550
1551/* Fail commands. Mutex and session lock held and recv side suspended */
1552static void fail_all_commands(struct iscsi_conn *conn)
1553{
1554 struct iscsi_cmd_task *ctask, *tmp;
1555
1556 /* flush pending */
1557 while (__kfifo_get(conn->xmitqueue, (void*)&ctask, sizeof(void*))) {
1558 debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc,
1559 ctask->itt);
1560 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1561 }
1562
1563 /* fail all other running */
1564 list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) {
1565 debug_scsi("failing in progress sc %p itt 0x%x\n",
1566 ctask->sc, ctask->itt);
1567 fail_command(conn, ctask, DID_BUS_BUSY << 16);
1568 }
1569
1570 conn->ctask = NULL;
1571}
1572
1573void iscsi_start_session_recovery(struct iscsi_session *session,
1574 struct iscsi_conn *conn, int flag)
1575{
1576 spin_lock_bh(&session->lock);
1577 if (conn->stop_stage == STOP_CONN_RECOVER ||
1578 conn->stop_stage == STOP_CONN_TERM) {
1579 spin_unlock_bh(&session->lock);
1580 return;
1581 }
1582 conn->stop_stage = flag;
1583 spin_unlock_bh(&session->lock);
1584
1585 if (session->tt->suspend_conn_recv)
1586 session->tt->suspend_conn_recv(conn);
1587
1588 mutex_lock(&conn->xmitmutex);
1589 spin_lock_bh(&session->lock);
1590 conn->c_stage = ISCSI_CONN_STOPPED;
1591 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1592
1593 session->conn_cnt--;
1594 if (session->conn_cnt == 0 || session->leadconn == conn)
1595 session->state = ISCSI_STATE_FAILED;
1596
1597 spin_unlock_bh(&session->lock);
1598
1599 session->tt->terminate_conn(conn);
1600 /*
1601 * flush queues.
1602 */
1603 spin_lock_bh(&session->lock);
1604 fail_all_commands(conn);
1605 flush_control_queues(session, conn);
1606 spin_unlock_bh(&session->lock);
1607
1608 /*
1609 * for connection level recovery we should not calculate
1610 * header digest. conn->hdr_size used for optimization
1611 * in hdr_extract() and will be re-negotiated at
1612 * set_param() time.
1613 */
1614 if (flag == STOP_CONN_RECOVER) {
1615 conn->hdrdgst_en = 0;
1616 conn->datadgst_en = 0;
1617
1618 if (session->state == ISCSI_STATE_FAILED)
1619 iscsi_block_session(session_to_cls(session));
1620 }
1621 mutex_unlock(&conn->xmitmutex);
1622}
1623EXPORT_SYMBOL_GPL(iscsi_start_session_recovery);
1624
1625void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
1626{
1627 struct iscsi_conn *conn = cls_conn->dd_data;
1628 struct iscsi_session *session = conn->session;
1629
1630 switch (flag) {
1631 case STOP_CONN_RECOVER:
1632 case STOP_CONN_TERM:
1633 iscsi_start_session_recovery(session, conn, flag);
1634 return;
1635 case STOP_CONN_SUSPEND:
1636 if (session->tt->suspend_conn_recv)
1637 session->tt->suspend_conn_recv(conn);
1638
1639 mutex_lock(&conn->xmitmutex);
1640 spin_lock_bh(&session->lock);
1641
1642 conn->stop_stage = flag;
1643 conn->c_stage = ISCSI_CONN_STOPPED;
1644 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1645
1646 spin_unlock_bh(&session->lock);
1647 mutex_unlock(&conn->xmitmutex);
1648 break;
1649 default:
1650 printk(KERN_ERR "invalid stop flag %d\n", flag);
1651 }
1652}
1653EXPORT_SYMBOL_GPL(iscsi_conn_stop);
1654
1655int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
1656 struct iscsi_cls_conn *cls_conn, int is_leading)
1657{
1658 struct iscsi_session *session = class_to_transport_session(cls_session);
1659 struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data;
1660
1661 /* lookup for existing connection */
1662 spin_lock_bh(&session->lock);
1663 list_for_each_entry(tmp, &session->connections, item) {
1664 if (tmp == conn) {
1665 if (conn->c_stage != ISCSI_CONN_STOPPED ||
1666 conn->stop_stage == STOP_CONN_TERM) {
1667 printk(KERN_ERR "iscsi_tcp: can't bind "
1668 "non-stopped connection (%d:%d)\n",
1669 conn->c_stage, conn->stop_stage);
1670 spin_unlock_bh(&session->lock);
1671 return -EIO;
1672 }
1673 break;
1674 }
1675 }
1676 if (tmp != conn) {
1677 /* bind new iSCSI connection to session */
1678 conn->session = session;
1679 list_add(&conn->item, &session->connections);
1680 }
1681 spin_unlock_bh(&session->lock);
1682
1683 if (is_leading)
1684 session->leadconn = conn;
1685
1686 /*
1687 * Unblock xmitworker(), Login Phase will pass through.
1688 */
1689 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1690 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1691 return 0;
1692}
1693EXPORT_SYMBOL_GPL(iscsi_conn_bind);
1694
1695MODULE_AUTHOR("Mike Christie");
1696MODULE_DESCRIPTION("iSCSI library functions");
1697MODULE_LICENSE("GPL");
Clone of davem's net-next-2.6 tree