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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/kfifo.h>
26#include <linux/delay.h>
27#include <linux/log2.h>
28#include <linux/slab.h>
29#include <linux/sched/signal.h>
30#include <linux/module.h>
31#include <asm/unaligned.h>
32#include <net/tcp.h>
33#include <scsi/scsi_cmnd.h>
34#include <scsi/scsi_device.h>
35#include <scsi/scsi_eh.h>
36#include <scsi/scsi_tcq.h>
37#include <scsi/scsi_host.h>
38#include <scsi/scsi.h>
39#include <scsi/iscsi_proto.h>
40#include <scsi/scsi_transport.h>
41#include <scsi/scsi_transport_iscsi.h>
42#include <scsi/libiscsi.h>
43
44static int iscsi_dbg_lib_conn;
45module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
46 S_IRUGO | S_IWUSR);
47MODULE_PARM_DESC(debug_libiscsi_conn,
48 "Turn on debugging for connections in libiscsi module. "
49 "Set to 1 to turn on, and zero to turn off. Default is off.");
50
51static int iscsi_dbg_lib_session;
52module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
53 S_IRUGO | S_IWUSR);
54MODULE_PARM_DESC(debug_libiscsi_session,
55 "Turn on debugging for sessions in libiscsi module. "
56 "Set to 1 to turn on, and zero to turn off. Default is off.");
57
58static int iscsi_dbg_lib_eh;
59module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
60 S_IRUGO | S_IWUSR);
61MODULE_PARM_DESC(debug_libiscsi_eh,
62 "Turn on debugging for error handling in libiscsi module. "
63 "Set to 1 to turn on, and zero to turn off. Default is off.");
64
65#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...) \
66 do { \
67 if (iscsi_dbg_lib_conn) \
68 iscsi_conn_printk(KERN_INFO, _conn, \
69 "%s " dbg_fmt, \
70 __func__, ##arg); \
71 } while (0);
72
73#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...) \
74 do { \
75 if (iscsi_dbg_lib_session) \
76 iscsi_session_printk(KERN_INFO, _session, \
77 "%s " dbg_fmt, \
78 __func__, ##arg); \
79 } while (0);
80
81#define ISCSI_DBG_EH(_session, dbg_fmt, arg...) \
82 do { \
83 if (iscsi_dbg_lib_eh) \
84 iscsi_session_printk(KERN_INFO, _session, \
85 "%s " dbg_fmt, \
86 __func__, ##arg); \
87 } while (0);
88
89inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
90{
91 struct Scsi_Host *shost = conn->session->host;
92 struct iscsi_host *ihost = shost_priv(shost);
93
94 if (ihost->workq)
95 queue_work(ihost->workq, &conn->xmitwork);
96}
97EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
98
99static void __iscsi_update_cmdsn(struct iscsi_session *session,
100 uint32_t exp_cmdsn, uint32_t max_cmdsn)
101{
102 /*
103 * standard specifies this check for when to update expected and
104 * max sequence numbers
105 */
106 if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
107 return;
108
109 if (exp_cmdsn != session->exp_cmdsn &&
110 !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
111 session->exp_cmdsn = exp_cmdsn;
112
113 if (max_cmdsn != session->max_cmdsn &&
114 !iscsi_sna_lt(max_cmdsn, session->max_cmdsn))
115 session->max_cmdsn = max_cmdsn;
116}
117
118void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
119{
120 __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
121 be32_to_cpu(hdr->max_cmdsn));
122}
123EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
124
125/**
126 * iscsi_prep_data_out_pdu - initialize Data-Out
127 * @task: scsi command task
128 * @r2t: R2T info
129 * @hdr: iscsi data in pdu
130 *
131 * Notes:
132 * Initialize Data-Out within this R2T sequence and finds
133 * proper data_offset within this SCSI command.
134 *
135 * This function is called with connection lock taken.
136 **/
137void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
138 struct iscsi_data *hdr)
139{
140 struct iscsi_conn *conn = task->conn;
141 unsigned int left = r2t->data_length - r2t->sent;
142
143 task->hdr_len = sizeof(struct iscsi_data);
144
145 memset(hdr, 0, sizeof(struct iscsi_data));
146 hdr->ttt = r2t->ttt;
147 hdr->datasn = cpu_to_be32(r2t->datasn);
148 r2t->datasn++;
149 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
150 hdr->lun = task->lun;
151 hdr->itt = task->hdr_itt;
152 hdr->exp_statsn = r2t->exp_statsn;
153 hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
154 if (left > conn->max_xmit_dlength) {
155 hton24(hdr->dlength, conn->max_xmit_dlength);
156 r2t->data_count = conn->max_xmit_dlength;
157 hdr->flags = 0;
158 } else {
159 hton24(hdr->dlength, left);
160 r2t->data_count = left;
161 hdr->flags = ISCSI_FLAG_CMD_FINAL;
162 }
163 conn->dataout_pdus_cnt++;
164}
165EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
166
167static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
168{
169 unsigned exp_len = task->hdr_len + len;
170
171 if (exp_len > task->hdr_max) {
172 WARN_ON(1);
173 return -EINVAL;
174 }
175
176 WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
177 task->hdr_len = exp_len;
178 return 0;
179}
180
181/*
182 * make an extended cdb AHS
183 */
184static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
185{
186 struct scsi_cmnd *cmd = task->sc;
187 unsigned rlen, pad_len;
188 unsigned short ahslength;
189 struct iscsi_ecdb_ahdr *ecdb_ahdr;
190 int rc;
191
192 ecdb_ahdr = iscsi_next_hdr(task);
193 rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
194
195 BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
196 ahslength = rlen + sizeof(ecdb_ahdr->reserved);
197
198 pad_len = iscsi_padding(rlen);
199
200 rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
201 sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
202 if (rc)
203 return rc;
204
205 if (pad_len)
206 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
207
208 ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
209 ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
210 ecdb_ahdr->reserved = 0;
211 memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
212
213 ISCSI_DBG_SESSION(task->conn->session,
214 "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
215 "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
216 "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
217 task->hdr_len);
218 return 0;
219}
220
221static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
222{
223 struct scsi_cmnd *sc = task->sc;
224 struct iscsi_rlength_ahdr *rlen_ahdr;
225 int rc;
226
227 rlen_ahdr = iscsi_next_hdr(task);
228 rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
229 if (rc)
230 return rc;
231
232 rlen_ahdr->ahslength =
233 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
234 sizeof(rlen_ahdr->reserved));
235 rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
236 rlen_ahdr->reserved = 0;
237 rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
238
239 ISCSI_DBG_SESSION(task->conn->session,
240 "bidi-in rlen_ahdr->read_length(%d) "
241 "rlen_ahdr->ahslength(%d)\n",
242 be32_to_cpu(rlen_ahdr->read_length),
243 be16_to_cpu(rlen_ahdr->ahslength));
244 return 0;
245}
246
247/**
248 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
249 * @task: iscsi task
250 * @opcode: opcode to check for
251 *
252 * During TMF a task has to be checked if it's affected.
253 * All unrelated I/O can be passed through, but I/O to the
254 * affected LUN should be restricted.
255 * If 'fast_abort' is set we won't be sending any I/O to the
256 * affected LUN.
257 * Otherwise the target is waiting for all TTTs to be completed,
258 * so we have to send all outstanding Data-Out PDUs to the target.
259 */
260static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
261{
262 struct iscsi_conn *conn = task->conn;
263 struct iscsi_tm *tmf = &conn->tmhdr;
264 u64 hdr_lun;
265
266 if (conn->tmf_state == TMF_INITIAL)
267 return 0;
268
269 if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
270 return 0;
271
272 switch (ISCSI_TM_FUNC_VALUE(tmf)) {
273 case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
274 /*
275 * Allow PDUs for unrelated LUNs
276 */
277 hdr_lun = scsilun_to_int(&tmf->lun);
278 if (hdr_lun != task->sc->device->lun)
279 return 0;
280 /* fall through */
281 case ISCSI_TM_FUNC_TARGET_WARM_RESET:
282 /*
283 * Fail all SCSI cmd PDUs
284 */
285 if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
286 iscsi_conn_printk(KERN_INFO, conn,
287 "task [op %x/%x itt "
288 "0x%x/0x%x] "
289 "rejected.\n",
290 task->hdr->opcode, opcode,
291 task->itt, task->hdr_itt);
292 return -EACCES;
293 }
294 /*
295 * And also all data-out PDUs in response to R2T
296 * if fast_abort is set.
297 */
298 if (conn->session->fast_abort) {
299 iscsi_conn_printk(KERN_INFO, conn,
300 "task [op %x/%x itt "
301 "0x%x/0x%x] fast abort.\n",
302 task->hdr->opcode, opcode,
303 task->itt, task->hdr_itt);
304 return -EACCES;
305 }
306 break;
307 case ISCSI_TM_FUNC_ABORT_TASK:
308 /*
309 * the caller has already checked if the task
310 * they want to abort was in the pending queue so if
311 * we are here the cmd pdu has gone out already, and
312 * we will only hit this for data-outs
313 */
314 if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
315 task->hdr_itt == tmf->rtt) {
316 ISCSI_DBG_SESSION(conn->session,
317 "Preventing task %x/%x from sending "
318 "data-out due to abort task in "
319 "progress\n", task->itt,
320 task->hdr_itt);
321 return -EACCES;
322 }
323 break;
324 }
325
326 return 0;
327}
328
329/**
330 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
331 * @task: iscsi task
332 *
333 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
334 * fields like dlength or final based on how much data it sends
335 */
336static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
337{
338 struct iscsi_conn *conn = task->conn;
339 struct iscsi_session *session = conn->session;
340 struct scsi_cmnd *sc = task->sc;
341 struct iscsi_scsi_req *hdr;
342 unsigned hdrlength, cmd_len, transfer_length;
343 itt_t itt;
344 int rc;
345
346 rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
347 if (rc)
348 return rc;
349
350 if (conn->session->tt->alloc_pdu) {
351 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
352 if (rc)
353 return rc;
354 }
355 hdr = (struct iscsi_scsi_req *)task->hdr;
356 itt = hdr->itt;
357 memset(hdr, 0, sizeof(*hdr));
358
359 if (session->tt->parse_pdu_itt)
360 hdr->itt = task->hdr_itt = itt;
361 else
362 hdr->itt = task->hdr_itt = build_itt(task->itt,
363 task->conn->session->age);
364 task->hdr_len = 0;
365 rc = iscsi_add_hdr(task, sizeof(*hdr));
366 if (rc)
367 return rc;
368 hdr->opcode = ISCSI_OP_SCSI_CMD;
369 hdr->flags = ISCSI_ATTR_SIMPLE;
370 int_to_scsilun(sc->device->lun, &hdr->lun);
371 task->lun = hdr->lun;
372 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
373 cmd_len = sc->cmd_len;
374 if (cmd_len < ISCSI_CDB_SIZE)
375 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
376 else if (cmd_len > ISCSI_CDB_SIZE) {
377 rc = iscsi_prep_ecdb_ahs(task);
378 if (rc)
379 return rc;
380 cmd_len = ISCSI_CDB_SIZE;
381 }
382 memcpy(hdr->cdb, sc->cmnd, cmd_len);
383
384 task->imm_count = 0;
385 if (scsi_bidi_cmnd(sc)) {
386 hdr->flags |= ISCSI_FLAG_CMD_READ;
387 rc = iscsi_prep_bidi_ahs(task);
388 if (rc)
389 return rc;
390 }
391
392 if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL)
393 task->protected = true;
394
395 transfer_length = scsi_transfer_length(sc);
396 hdr->data_length = cpu_to_be32(transfer_length);
397 if (sc->sc_data_direction == DMA_TO_DEVICE) {
398 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
399
400 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
401 /*
402 * Write counters:
403 *
404 * imm_count bytes to be sent right after
405 * SCSI PDU Header
406 *
407 * unsol_count bytes(as Data-Out) to be sent
408 * without R2T ack right after
409 * immediate data
410 *
411 * r2t data_length bytes to be sent via R2T ack's
412 *
413 * pad_count bytes to be sent as zero-padding
414 */
415 memset(r2t, 0, sizeof(*r2t));
416
417 if (session->imm_data_en) {
418 if (transfer_length >= session->first_burst)
419 task->imm_count = min(session->first_burst,
420 conn->max_xmit_dlength);
421 else
422 task->imm_count = min(transfer_length,
423 conn->max_xmit_dlength);
424 hton24(hdr->dlength, task->imm_count);
425 } else
426 zero_data(hdr->dlength);
427
428 if (!session->initial_r2t_en) {
429 r2t->data_length = min(session->first_burst,
430 transfer_length) -
431 task->imm_count;
432 r2t->data_offset = task->imm_count;
433 r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
434 r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
435 }
436
437 if (!task->unsol_r2t.data_length)
438 /* No unsolicit Data-Out's */
439 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
440 } else {
441 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
442 zero_data(hdr->dlength);
443
444 if (sc->sc_data_direction == DMA_FROM_DEVICE)
445 hdr->flags |= ISCSI_FLAG_CMD_READ;
446 }
447
448 /* calculate size of additional header segments (AHSs) */
449 hdrlength = task->hdr_len - sizeof(*hdr);
450
451 WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
452 hdrlength /= ISCSI_PAD_LEN;
453
454 WARN_ON(hdrlength >= 256);
455 hdr->hlength = hdrlength & 0xFF;
456 hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
457
458 if (session->tt->init_task && session->tt->init_task(task))
459 return -EIO;
460
461 task->state = ISCSI_TASK_RUNNING;
462 session->cmdsn++;
463
464 conn->scsicmd_pdus_cnt++;
465 ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
466 "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
467 scsi_bidi_cmnd(sc) ? "bidirectional" :
468 sc->sc_data_direction == DMA_TO_DEVICE ?
469 "write" : "read", conn->id, sc, sc->cmnd[0],
470 task->itt, transfer_length,
471 scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
472 session->cmdsn,
473 session->max_cmdsn - session->exp_cmdsn + 1);
474 return 0;
475}
476
477/**
478 * iscsi_free_task - free a task
479 * @task: iscsi cmd task
480 *
481 * Must be called with session back_lock.
482 * This function returns the scsi command to scsi-ml or cleans
483 * up mgmt tasks then returns the task to the pool.
484 */
485static void iscsi_free_task(struct iscsi_task *task)
486{
487 struct iscsi_conn *conn = task->conn;
488 struct iscsi_session *session = conn->session;
489 struct scsi_cmnd *sc = task->sc;
490 int oldstate = task->state;
491
492 ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
493 task->itt, task->state, task->sc);
494
495 session->tt->cleanup_task(task);
496 task->state = ISCSI_TASK_FREE;
497 task->sc = NULL;
498 /*
499 * login task is preallocated so do not free
500 */
501 if (conn->login_task == task)
502 return;
503
504 kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
505
506 if (sc) {
507 /* SCSI eh reuses commands to verify us */
508 sc->SCp.ptr = NULL;
509 /*
510 * queue command may call this to free the task, so
511 * it will decide how to return sc to scsi-ml.
512 */
513 if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
514 sc->scsi_done(sc);
515 }
516}
517
518void __iscsi_get_task(struct iscsi_task *task)
519{
520 refcount_inc(&task->refcount);
521}
522EXPORT_SYMBOL_GPL(__iscsi_get_task);
523
524void __iscsi_put_task(struct iscsi_task *task)
525{
526 if (refcount_dec_and_test(&task->refcount))
527 iscsi_free_task(task);
528}
529EXPORT_SYMBOL_GPL(__iscsi_put_task);
530
531void iscsi_put_task(struct iscsi_task *task)
532{
533 struct iscsi_session *session = task->conn->session;
534
535 /* regular RX path uses back_lock */
536 spin_lock_bh(&session->back_lock);
537 __iscsi_put_task(task);
538 spin_unlock_bh(&session->back_lock);
539}
540EXPORT_SYMBOL_GPL(iscsi_put_task);
541
542/**
543 * iscsi_complete_task - finish a task
544 * @task: iscsi cmd task
545 * @state: state to complete task with
546 *
547 * Must be called with session back_lock.
548 */
549static void iscsi_complete_task(struct iscsi_task *task, int state)
550{
551 struct iscsi_conn *conn = task->conn;
552
553 ISCSI_DBG_SESSION(conn->session,
554 "complete task itt 0x%x state %d sc %p\n",
555 task->itt, task->state, task->sc);
556 if (task->state == ISCSI_TASK_COMPLETED ||
557 task->state == ISCSI_TASK_ABRT_TMF ||
558 task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
559 task->state == ISCSI_TASK_REQUEUE_SCSIQ)
560 return;
561 WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
562 task->state = state;
563
564 spin_lock_bh(&conn->taskqueuelock);
565 if (!list_empty(&task->running)) {
566 pr_debug_once("%s while task on list", __func__);
567 list_del_init(&task->running);
568 }
569 spin_unlock_bh(&conn->taskqueuelock);
570
571 if (conn->task == task)
572 conn->task = NULL;
573
574 if (conn->ping_task == task)
575 conn->ping_task = NULL;
576
577 /* release get from queueing */
578 __iscsi_put_task(task);
579}
580
581/**
582 * iscsi_complete_scsi_task - finish scsi task normally
583 * @task: iscsi task for scsi cmd
584 * @exp_cmdsn: expected cmd sn in cpu format
585 * @max_cmdsn: max cmd sn in cpu format
586 *
587 * This is used when drivers do not need or cannot perform
588 * lower level pdu processing.
589 *
590 * Called with session back_lock
591 */
592void iscsi_complete_scsi_task(struct iscsi_task *task,
593 uint32_t exp_cmdsn, uint32_t max_cmdsn)
594{
595 struct iscsi_conn *conn = task->conn;
596
597 ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
598
599 conn->last_recv = jiffies;
600 __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
601 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
602}
603EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
604
605
606/*
607 * session back_lock must be held and if not called for a task that is
608 * still pending or from the xmit thread, then xmit thread must
609 * be suspended.
610 */
611static void fail_scsi_task(struct iscsi_task *task, int err)
612{
613 struct iscsi_conn *conn = task->conn;
614 struct scsi_cmnd *sc;
615 int state;
616
617 /*
618 * if a command completes and we get a successful tmf response
619 * we will hit this because the scsi eh abort code does not take
620 * a ref to the task.
621 */
622 sc = task->sc;
623 if (!sc)
624 return;
625
626 if (task->state == ISCSI_TASK_PENDING) {
627 /*
628 * cmd never made it to the xmit thread, so we should not count
629 * the cmd in the sequencing
630 */
631 conn->session->queued_cmdsn--;
632 /* it was never sent so just complete like normal */
633 state = ISCSI_TASK_COMPLETED;
634 } else if (err == DID_TRANSPORT_DISRUPTED)
635 state = ISCSI_TASK_ABRT_SESS_RECOV;
636 else
637 state = ISCSI_TASK_ABRT_TMF;
638
639 sc->result = err << 16;
640 if (!scsi_bidi_cmnd(sc))
641 scsi_set_resid(sc, scsi_bufflen(sc));
642 else {
643 scsi_out(sc)->resid = scsi_out(sc)->length;
644 scsi_in(sc)->resid = scsi_in(sc)->length;
645 }
646
647 /* regular RX path uses back_lock */
648 spin_lock_bh(&conn->session->back_lock);
649 iscsi_complete_task(task, state);
650 spin_unlock_bh(&conn->session->back_lock);
651}
652
653static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
654 struct iscsi_task *task)
655{
656 struct iscsi_session *session = conn->session;
657 struct iscsi_hdr *hdr = task->hdr;
658 struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
659 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
660
661 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
662 return -ENOTCONN;
663
664 if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
665 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
666 /*
667 * pre-format CmdSN for outgoing PDU.
668 */
669 nop->cmdsn = cpu_to_be32(session->cmdsn);
670 if (hdr->itt != RESERVED_ITT) {
671 /*
672 * TODO: We always use immediate for normal session pdus.
673 * If we start to send tmfs or nops as non-immediate then
674 * we should start checking the cmdsn numbers for mgmt tasks.
675 *
676 * During discovery sessions iscsid sends TEXT as non immediate,
677 * but we always only send one PDU at a time.
678 */
679 if (conn->c_stage == ISCSI_CONN_STARTED &&
680 !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
681 session->queued_cmdsn++;
682 session->cmdsn++;
683 }
684 }
685
686 if (session->tt->init_task && session->tt->init_task(task))
687 return -EIO;
688
689 if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
690 session->state = ISCSI_STATE_LOGGING_OUT;
691
692 task->state = ISCSI_TASK_RUNNING;
693 ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
694 "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
695 hdr->itt, task->data_count);
696 return 0;
697}
698
699static struct iscsi_task *
700__iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
701 char *data, uint32_t data_size)
702{
703 struct iscsi_session *session = conn->session;
704 struct iscsi_host *ihost = shost_priv(session->host);
705 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
706 struct iscsi_task *task;
707 itt_t itt;
708
709 if (session->state == ISCSI_STATE_TERMINATE)
710 return NULL;
711
712 if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
713 /*
714 * Login and Text are sent serially, in
715 * request-followed-by-response sequence.
716 * Same task can be used. Same ITT must be used.
717 * Note that login_task is preallocated at conn_create().
718 */
719 if (conn->login_task->state != ISCSI_TASK_FREE) {
720 iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
721 "progress. Cannot start new task.\n");
722 return NULL;
723 }
724
725 if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
726 iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN);
727 return NULL;
728 }
729
730 task = conn->login_task;
731 } else {
732 if (session->state != ISCSI_STATE_LOGGED_IN)
733 return NULL;
734
735 if (data_size != 0) {
736 iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
737 return NULL;
738 }
739
740 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
741 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
742
743 if (!kfifo_out(&session->cmdpool.queue,
744 (void*)&task, sizeof(void*)))
745 return NULL;
746 }
747 /*
748 * released in complete pdu for task we expect a response for, and
749 * released by the lld when it has transmitted the task for
750 * pdus we do not expect a response for.
751 */
752 refcount_set(&task->refcount, 1);
753 task->conn = conn;
754 task->sc = NULL;
755 INIT_LIST_HEAD(&task->running);
756 task->state = ISCSI_TASK_PENDING;
757
758 if (data_size) {
759 memcpy(task->data, data, data_size);
760 task->data_count = data_size;
761 } else
762 task->data_count = 0;
763
764 if (conn->session->tt->alloc_pdu) {
765 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
766 iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
767 "pdu for mgmt task.\n");
768 goto free_task;
769 }
770 }
771
772 itt = task->hdr->itt;
773 task->hdr_len = sizeof(struct iscsi_hdr);
774 memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
775
776 if (hdr->itt != RESERVED_ITT) {
777 if (session->tt->parse_pdu_itt)
778 task->hdr->itt = itt;
779 else
780 task->hdr->itt = build_itt(task->itt,
781 task->conn->session->age);
782 }
783
784 if (!ihost->workq) {
785 if (iscsi_prep_mgmt_task(conn, task))
786 goto free_task;
787
788 if (session->tt->xmit_task(task))
789 goto free_task;
790 } else {
791 spin_lock_bh(&conn->taskqueuelock);
792 list_add_tail(&task->running, &conn->mgmtqueue);
793 spin_unlock_bh(&conn->taskqueuelock);
794 iscsi_conn_queue_work(conn);
795 }
796
797 return task;
798
799free_task:
800 /* regular RX path uses back_lock */
801 spin_lock(&session->back_lock);
802 __iscsi_put_task(task);
803 spin_unlock(&session->back_lock);
804 return NULL;
805}
806
807int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
808 char *data, uint32_t data_size)
809{
810 struct iscsi_conn *conn = cls_conn->dd_data;
811 struct iscsi_session *session = conn->session;
812 int err = 0;
813
814 spin_lock_bh(&session->frwd_lock);
815 if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
816 err = -EPERM;
817 spin_unlock_bh(&session->frwd_lock);
818 return err;
819}
820EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
821
822/**
823 * iscsi_cmd_rsp - SCSI Command Response processing
824 * @conn: iscsi connection
825 * @hdr: iscsi header
826 * @task: scsi command task
827 * @data: cmd data buffer
828 * @datalen: len of buffer
829 *
830 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
831 * then completes the command and task.
832 **/
833static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
834 struct iscsi_task *task, char *data,
835 int datalen)
836{
837 struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
838 struct iscsi_session *session = conn->session;
839 struct scsi_cmnd *sc = task->sc;
840
841 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
842 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
843
844 sc->result = (DID_OK << 16) | rhdr->cmd_status;
845
846 if (task->protected) {
847 sector_t sector;
848 u8 ascq;
849
850 /**
851 * Transports that didn't implement check_protection
852 * callback but still published T10-PI support to scsi-mid
853 * deserve this BUG_ON.
854 **/
855 BUG_ON(!session->tt->check_protection);
856
857 ascq = session->tt->check_protection(task, §or);
858 if (ascq) {
859 sc->result = DRIVER_SENSE << 24 |
860 SAM_STAT_CHECK_CONDITION;
861 scsi_build_sense_buffer(1, sc->sense_buffer,
862 ILLEGAL_REQUEST, 0x10, ascq);
863 scsi_set_sense_information(sc->sense_buffer,
864 SCSI_SENSE_BUFFERSIZE,
865 sector);
866 goto out;
867 }
868 }
869
870 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
871 sc->result = DID_ERROR << 16;
872 goto out;
873 }
874
875 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
876 uint16_t senselen;
877
878 if (datalen < 2) {
879invalid_datalen:
880 iscsi_conn_printk(KERN_ERR, conn,
881 "Got CHECK_CONDITION but invalid data "
882 "buffer size of %d\n", datalen);
883 sc->result = DID_BAD_TARGET << 16;
884 goto out;
885 }
886
887 senselen = get_unaligned_be16(data);
888 if (datalen < senselen)
889 goto invalid_datalen;
890
891 memcpy(sc->sense_buffer, data + 2,
892 min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
893 ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
894 min_t(uint16_t, senselen,
895 SCSI_SENSE_BUFFERSIZE));
896 }
897
898 if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
899 ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
900 int res_count = be32_to_cpu(rhdr->bi_residual_count);
901
902 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
903 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
904 res_count <= scsi_in(sc)->length))
905 scsi_in(sc)->resid = res_count;
906 else
907 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
908 }
909
910 if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
911 ISCSI_FLAG_CMD_OVERFLOW)) {
912 int res_count = be32_to_cpu(rhdr->residual_count);
913
914 if (res_count > 0 &&
915 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
916 res_count <= scsi_bufflen(sc)))
917 /* write side for bidi or uni-io set_resid */
918 scsi_set_resid(sc, res_count);
919 else
920 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
921 }
922out:
923 ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
924 sc, sc->result, task->itt);
925 conn->scsirsp_pdus_cnt++;
926 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
927}
928
929/**
930 * iscsi_data_in_rsp - SCSI Data-In Response processing
931 * @conn: iscsi connection
932 * @hdr: iscsi pdu
933 * @task: scsi command task
934 **/
935static void
936iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
937 struct iscsi_task *task)
938{
939 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
940 struct scsi_cmnd *sc = task->sc;
941
942 if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
943 return;
944
945 iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
946 sc->result = (DID_OK << 16) | rhdr->cmd_status;
947 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
948 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
949 ISCSI_FLAG_DATA_OVERFLOW)) {
950 int res_count = be32_to_cpu(rhdr->residual_count);
951
952 if (res_count > 0 &&
953 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
954 res_count <= scsi_in(sc)->length))
955 scsi_in(sc)->resid = res_count;
956 else
957 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
958 }
959
960 ISCSI_DBG_SESSION(conn->session, "data in with status done "
961 "[sc %p res %d itt 0x%x]\n",
962 sc, sc->result, task->itt);
963 conn->scsirsp_pdus_cnt++;
964 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
965}
966
967static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
968{
969 struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
970
971 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
972 conn->tmfrsp_pdus_cnt++;
973
974 if (conn->tmf_state != TMF_QUEUED)
975 return;
976
977 if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
978 conn->tmf_state = TMF_SUCCESS;
979 else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
980 conn->tmf_state = TMF_NOT_FOUND;
981 else
982 conn->tmf_state = TMF_FAILED;
983 wake_up(&conn->ehwait);
984}
985
986static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
987{
988 struct iscsi_nopout hdr;
989 struct iscsi_task *task;
990
991 if (!rhdr && conn->ping_task)
992 return -EINVAL;
993
994 memset(&hdr, 0, sizeof(struct iscsi_nopout));
995 hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
996 hdr.flags = ISCSI_FLAG_CMD_FINAL;
997
998 if (rhdr) {
999 hdr.lun = rhdr->lun;
1000 hdr.ttt = rhdr->ttt;
1001 hdr.itt = RESERVED_ITT;
1002 } else
1003 hdr.ttt = RESERVED_ITT;
1004
1005 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
1006 if (!task) {
1007 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
1008 return -EIO;
1009 } else if (!rhdr) {
1010 /* only track our nops */
1011 conn->ping_task = task;
1012 conn->last_ping = jiffies;
1013 }
1014
1015 return 0;
1016}
1017
1018static int iscsi_nop_out_rsp(struct iscsi_task *task,
1019 struct iscsi_nopin *nop, char *data, int datalen)
1020{
1021 struct iscsi_conn *conn = task->conn;
1022 int rc = 0;
1023
1024 if (conn->ping_task != task) {
1025 /*
1026 * If this is not in response to one of our
1027 * nops then it must be from userspace.
1028 */
1029 if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
1030 data, datalen))
1031 rc = ISCSI_ERR_CONN_FAILED;
1032 } else
1033 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
1034 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1035 return rc;
1036}
1037
1038static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1039 char *data, int datalen)
1040{
1041 struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1042 struct iscsi_hdr rejected_pdu;
1043 int opcode, rc = 0;
1044
1045 conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1046
1047 if (ntoh24(reject->dlength) > datalen ||
1048 ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1049 iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1050 "pdu. Invalid data length (pdu dlength "
1051 "%u, datalen %d\n", ntoh24(reject->dlength),
1052 datalen);
1053 return ISCSI_ERR_PROTO;
1054 }
1055 memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1056 opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1057
1058 switch (reject->reason) {
1059 case ISCSI_REASON_DATA_DIGEST_ERROR:
1060 iscsi_conn_printk(KERN_ERR, conn,
1061 "pdu (op 0x%x itt 0x%x) rejected "
1062 "due to DataDigest error.\n",
1063 opcode, rejected_pdu.itt);
1064 break;
1065 case ISCSI_REASON_IMM_CMD_REJECT:
1066 iscsi_conn_printk(KERN_ERR, conn,
1067 "pdu (op 0x%x itt 0x%x) rejected. Too many "
1068 "immediate commands.\n",
1069 opcode, rejected_pdu.itt);
1070 /*
1071 * We only send one TMF at a time so if the target could not
1072 * handle it, then it should get fixed (RFC mandates that
1073 * a target can handle one immediate TMF per conn).
1074 *
1075 * For nops-outs, we could have sent more than one if
1076 * the target is sending us lots of nop-ins
1077 */
1078 if (opcode != ISCSI_OP_NOOP_OUT)
1079 return 0;
1080
1081 if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1082 /*
1083 * nop-out in response to target's nop-out rejected.
1084 * Just resend.
1085 */
1086 /* In RX path we are under back lock */
1087 spin_unlock(&conn->session->back_lock);
1088 spin_lock(&conn->session->frwd_lock);
1089 iscsi_send_nopout(conn,
1090 (struct iscsi_nopin*)&rejected_pdu);
1091 spin_unlock(&conn->session->frwd_lock);
1092 spin_lock(&conn->session->back_lock);
1093 } else {
1094 struct iscsi_task *task;
1095 /*
1096 * Our nop as ping got dropped. We know the target
1097 * and transport are ok so just clean up
1098 */
1099 task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1100 if (!task) {
1101 iscsi_conn_printk(KERN_ERR, conn,
1102 "Invalid pdu reject. Could "
1103 "not lookup rejected task.\n");
1104 rc = ISCSI_ERR_BAD_ITT;
1105 } else
1106 rc = iscsi_nop_out_rsp(task,
1107 (struct iscsi_nopin*)&rejected_pdu,
1108 NULL, 0);
1109 }
1110 break;
1111 default:
1112 iscsi_conn_printk(KERN_ERR, conn,
1113 "pdu (op 0x%x itt 0x%x) rejected. Reason "
1114 "code 0x%x\n", rejected_pdu.opcode,
1115 rejected_pdu.itt, reject->reason);
1116 break;
1117 }
1118 return rc;
1119}
1120
1121/**
1122 * iscsi_itt_to_task - look up task by itt
1123 * @conn: iscsi connection
1124 * @itt: itt
1125 *
1126 * This should be used for mgmt tasks like login and nops, or if
1127 * the LDD's itt space does not include the session age.
1128 *
1129 * The session back_lock must be held.
1130 */
1131struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1132{
1133 struct iscsi_session *session = conn->session;
1134 int i;
1135
1136 if (itt == RESERVED_ITT)
1137 return NULL;
1138
1139 if (session->tt->parse_pdu_itt)
1140 session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1141 else
1142 i = get_itt(itt);
1143 if (i >= session->cmds_max)
1144 return NULL;
1145
1146 return session->cmds[i];
1147}
1148EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1149
1150/**
1151 * __iscsi_complete_pdu - complete pdu
1152 * @conn: iscsi conn
1153 * @hdr: iscsi header
1154 * @data: data buffer
1155 * @datalen: len of data buffer
1156 *
1157 * Completes pdu processing by freeing any resources allocated at
1158 * queuecommand or send generic. session back_lock must be held and verify
1159 * itt must have been called.
1160 */
1161int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1162 char *data, int datalen)
1163{
1164 struct iscsi_session *session = conn->session;
1165 int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1166 struct iscsi_task *task;
1167 uint32_t itt;
1168
1169 conn->last_recv = jiffies;
1170 rc = iscsi_verify_itt(conn, hdr->itt);
1171 if (rc)
1172 return rc;
1173
1174 if (hdr->itt != RESERVED_ITT)
1175 itt = get_itt(hdr->itt);
1176 else
1177 itt = ~0U;
1178
1179 ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1180 opcode, conn->id, itt, datalen);
1181
1182 if (itt == ~0U) {
1183 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1184
1185 switch(opcode) {
1186 case ISCSI_OP_NOOP_IN:
1187 if (datalen) {
1188 rc = ISCSI_ERR_PROTO;
1189 break;
1190 }
1191
1192 if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1193 break;
1194
1195 /* In RX path we are under back lock */
1196 spin_unlock(&session->back_lock);
1197 spin_lock(&session->frwd_lock);
1198 iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1199 spin_unlock(&session->frwd_lock);
1200 spin_lock(&session->back_lock);
1201 break;
1202 case ISCSI_OP_REJECT:
1203 rc = iscsi_handle_reject(conn, hdr, data, datalen);
1204 break;
1205 case ISCSI_OP_ASYNC_EVENT:
1206 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1207 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1208 rc = ISCSI_ERR_CONN_FAILED;
1209 break;
1210 default:
1211 rc = ISCSI_ERR_BAD_OPCODE;
1212 break;
1213 }
1214 goto out;
1215 }
1216
1217 switch(opcode) {
1218 case ISCSI_OP_SCSI_CMD_RSP:
1219 case ISCSI_OP_SCSI_DATA_IN:
1220 task = iscsi_itt_to_ctask(conn, hdr->itt);
1221 if (!task)
1222 return ISCSI_ERR_BAD_ITT;
1223 task->last_xfer = jiffies;
1224 break;
1225 case ISCSI_OP_R2T:
1226 /*
1227 * LLD handles R2Ts if they need to.
1228 */
1229 return 0;
1230 case ISCSI_OP_LOGOUT_RSP:
1231 case ISCSI_OP_LOGIN_RSP:
1232 case ISCSI_OP_TEXT_RSP:
1233 case ISCSI_OP_SCSI_TMFUNC_RSP:
1234 case ISCSI_OP_NOOP_IN:
1235 task = iscsi_itt_to_task(conn, hdr->itt);
1236 if (!task)
1237 return ISCSI_ERR_BAD_ITT;
1238 break;
1239 default:
1240 return ISCSI_ERR_BAD_OPCODE;
1241 }
1242
1243 switch(opcode) {
1244 case ISCSI_OP_SCSI_CMD_RSP:
1245 iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1246 break;
1247 case ISCSI_OP_SCSI_DATA_IN:
1248 iscsi_data_in_rsp(conn, hdr, task);
1249 break;
1250 case ISCSI_OP_LOGOUT_RSP:
1251 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1252 if (datalen) {
1253 rc = ISCSI_ERR_PROTO;
1254 break;
1255 }
1256 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1257 goto recv_pdu;
1258 case ISCSI_OP_LOGIN_RSP:
1259 case ISCSI_OP_TEXT_RSP:
1260 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1261 /*
1262 * login related PDU's exp_statsn is handled in
1263 * userspace
1264 */
1265 goto recv_pdu;
1266 case ISCSI_OP_SCSI_TMFUNC_RSP:
1267 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1268 if (datalen) {
1269 rc = ISCSI_ERR_PROTO;
1270 break;
1271 }
1272
1273 iscsi_tmf_rsp(conn, hdr);
1274 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1275 break;
1276 case ISCSI_OP_NOOP_IN:
1277 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1278 if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1279 rc = ISCSI_ERR_PROTO;
1280 break;
1281 }
1282 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1283
1284 rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1285 data, datalen);
1286 break;
1287 default:
1288 rc = ISCSI_ERR_BAD_OPCODE;
1289 break;
1290 }
1291
1292out:
1293 return rc;
1294recv_pdu:
1295 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1296 rc = ISCSI_ERR_CONN_FAILED;
1297 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1298 return rc;
1299}
1300EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1301
1302int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1303 char *data, int datalen)
1304{
1305 int rc;
1306
1307 spin_lock(&conn->session->back_lock);
1308 rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1309 spin_unlock(&conn->session->back_lock);
1310 return rc;
1311}
1312EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1313
1314int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1315{
1316 struct iscsi_session *session = conn->session;
1317 int age = 0, i = 0;
1318
1319 if (itt == RESERVED_ITT)
1320 return 0;
1321
1322 if (session->tt->parse_pdu_itt)
1323 session->tt->parse_pdu_itt(conn, itt, &i, &age);
1324 else {
1325 i = get_itt(itt);
1326 age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1327 }
1328
1329 if (age != session->age) {
1330 iscsi_conn_printk(KERN_ERR, conn,
1331 "received itt %x expected session age (%x)\n",
1332 (__force u32)itt, session->age);
1333 return ISCSI_ERR_BAD_ITT;
1334 }
1335
1336 if (i >= session->cmds_max) {
1337 iscsi_conn_printk(KERN_ERR, conn,
1338 "received invalid itt index %u (max cmds "
1339 "%u.\n", i, session->cmds_max);
1340 return ISCSI_ERR_BAD_ITT;
1341 }
1342 return 0;
1343}
1344EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1345
1346/**
1347 * iscsi_itt_to_ctask - look up ctask by itt
1348 * @conn: iscsi connection
1349 * @itt: itt
1350 *
1351 * This should be used for cmd tasks.
1352 *
1353 * The session back_lock must be held.
1354 */
1355struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1356{
1357 struct iscsi_task *task;
1358
1359 if (iscsi_verify_itt(conn, itt))
1360 return NULL;
1361
1362 task = iscsi_itt_to_task(conn, itt);
1363 if (!task || !task->sc)
1364 return NULL;
1365
1366 if (task->sc->SCp.phase != conn->session->age) {
1367 iscsi_session_printk(KERN_ERR, conn->session,
1368 "task's session age %d, expected %d\n",
1369 task->sc->SCp.phase, conn->session->age);
1370 return NULL;
1371 }
1372
1373 return task;
1374}
1375EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1376
1377void iscsi_session_failure(struct iscsi_session *session,
1378 enum iscsi_err err)
1379{
1380 struct iscsi_conn *conn;
1381 struct device *dev;
1382
1383 spin_lock_bh(&session->frwd_lock);
1384 conn = session->leadconn;
1385 if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1386 spin_unlock_bh(&session->frwd_lock);
1387 return;
1388 }
1389
1390 dev = get_device(&conn->cls_conn->dev);
1391 spin_unlock_bh(&session->frwd_lock);
1392 if (!dev)
1393 return;
1394 /*
1395 * if the host is being removed bypass the connection
1396 * recovery initialization because we are going to kill
1397 * the session.
1398 */
1399 if (err == ISCSI_ERR_INVALID_HOST)
1400 iscsi_conn_error_event(conn->cls_conn, err);
1401 else
1402 iscsi_conn_failure(conn, err);
1403 put_device(dev);
1404}
1405EXPORT_SYMBOL_GPL(iscsi_session_failure);
1406
1407void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1408{
1409 struct iscsi_session *session = conn->session;
1410
1411 spin_lock_bh(&session->frwd_lock);
1412 if (session->state == ISCSI_STATE_FAILED) {
1413 spin_unlock_bh(&session->frwd_lock);
1414 return;
1415 }
1416
1417 if (conn->stop_stage == 0)
1418 session->state = ISCSI_STATE_FAILED;
1419 spin_unlock_bh(&session->frwd_lock);
1420
1421 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1422 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1423 iscsi_conn_error_event(conn->cls_conn, err);
1424}
1425EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1426
1427static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1428{
1429 struct iscsi_session *session = conn->session;
1430
1431 /*
1432 * Check for iSCSI window and take care of CmdSN wrap-around
1433 */
1434 if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1435 ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1436 "%u MaxCmdSN %u CmdSN %u/%u\n",
1437 session->exp_cmdsn, session->max_cmdsn,
1438 session->cmdsn, session->queued_cmdsn);
1439 return -ENOSPC;
1440 }
1441 return 0;
1442}
1443
1444static int iscsi_xmit_task(struct iscsi_conn *conn)
1445{
1446 struct iscsi_task *task = conn->task;
1447 int rc;
1448
1449 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
1450 return -ENODATA;
1451
1452 __iscsi_get_task(task);
1453 spin_unlock_bh(&conn->session->frwd_lock);
1454 rc = conn->session->tt->xmit_task(task);
1455 spin_lock_bh(&conn->session->frwd_lock);
1456 if (!rc) {
1457 /* done with this task */
1458 task->last_xfer = jiffies;
1459 conn->task = NULL;
1460 }
1461 /* regular RX path uses back_lock */
1462 spin_lock(&conn->session->back_lock);
1463 __iscsi_put_task(task);
1464 spin_unlock(&conn->session->back_lock);
1465 return rc;
1466}
1467
1468/**
1469 * iscsi_requeue_task - requeue task to run from session workqueue
1470 * @task: task to requeue
1471 *
1472 * LLDs that need to run a task from the session workqueue should call
1473 * this. The session frwd_lock must be held. This should only be called
1474 * by software drivers.
1475 */
1476void iscsi_requeue_task(struct iscsi_task *task)
1477{
1478 struct iscsi_conn *conn = task->conn;
1479
1480 /*
1481 * this may be on the requeue list already if the xmit_task callout
1482 * is handling the r2ts while we are adding new ones
1483 */
1484 spin_lock_bh(&conn->taskqueuelock);
1485 if (list_empty(&task->running))
1486 list_add_tail(&task->running, &conn->requeue);
1487 spin_unlock_bh(&conn->taskqueuelock);
1488 iscsi_conn_queue_work(conn);
1489}
1490EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1491
1492/**
1493 * iscsi_data_xmit - xmit any command into the scheduled connection
1494 * @conn: iscsi connection
1495 *
1496 * Notes:
1497 * The function can return -EAGAIN in which case the caller must
1498 * re-schedule it again later or recover. '0' return code means
1499 * successful xmit.
1500 **/
1501static int iscsi_data_xmit(struct iscsi_conn *conn)
1502{
1503 struct iscsi_task *task;
1504 int rc = 0;
1505
1506 spin_lock_bh(&conn->session->frwd_lock);
1507 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1508 ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1509 spin_unlock_bh(&conn->session->frwd_lock);
1510 return -ENODATA;
1511 }
1512
1513 if (conn->task) {
1514 rc = iscsi_xmit_task(conn);
1515 if (rc)
1516 goto done;
1517 }
1518
1519 /*
1520 * process mgmt pdus like nops before commands since we should
1521 * only have one nop-out as a ping from us and targets should not
1522 * overflow us with nop-ins
1523 */
1524 spin_lock_bh(&conn->taskqueuelock);
1525check_mgmt:
1526 while (!list_empty(&conn->mgmtqueue)) {
1527 conn->task = list_entry(conn->mgmtqueue.next,
1528 struct iscsi_task, running);
1529 list_del_init(&conn->task->running);
1530 spin_unlock_bh(&conn->taskqueuelock);
1531 if (iscsi_prep_mgmt_task(conn, conn->task)) {
1532 /* regular RX path uses back_lock */
1533 spin_lock_bh(&conn->session->back_lock);
1534 __iscsi_put_task(conn->task);
1535 spin_unlock_bh(&conn->session->back_lock);
1536 conn->task = NULL;
1537 spin_lock_bh(&conn->taskqueuelock);
1538 continue;
1539 }
1540 rc = iscsi_xmit_task(conn);
1541 if (rc)
1542 goto done;
1543 spin_lock_bh(&conn->taskqueuelock);
1544 }
1545
1546 /* process pending command queue */
1547 while (!list_empty(&conn->cmdqueue)) {
1548 conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1549 running);
1550 list_del_init(&conn->task->running);
1551 spin_unlock_bh(&conn->taskqueuelock);
1552 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1553 fail_scsi_task(conn->task, DID_IMM_RETRY);
1554 spin_lock_bh(&conn->taskqueuelock);
1555 continue;
1556 }
1557 rc = iscsi_prep_scsi_cmd_pdu(conn->task);
1558 if (rc) {
1559 if (rc == -ENOMEM || rc == -EACCES) {
1560 spin_lock_bh(&conn->taskqueuelock);
1561 list_add_tail(&conn->task->running,
1562 &conn->cmdqueue);
1563 conn->task = NULL;
1564 spin_unlock_bh(&conn->taskqueuelock);
1565 goto done;
1566 } else
1567 fail_scsi_task(conn->task, DID_ABORT);
1568 spin_lock_bh(&conn->taskqueuelock);
1569 continue;
1570 }
1571 rc = iscsi_xmit_task(conn);
1572 if (rc)
1573 goto done;
1574 /*
1575 * we could continuously get new task requests so
1576 * we need to check the mgmt queue for nops that need to
1577 * be sent to aviod starvation
1578 */
1579 spin_lock_bh(&conn->taskqueuelock);
1580 if (!list_empty(&conn->mgmtqueue))
1581 goto check_mgmt;
1582 }
1583
1584 while (!list_empty(&conn->requeue)) {
1585 /*
1586 * we always do fastlogout - conn stop code will clean up.
1587 */
1588 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1589 break;
1590
1591 task = list_entry(conn->requeue.next, struct iscsi_task,
1592 running);
1593 if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1594 break;
1595
1596 conn->task = task;
1597 list_del_init(&conn->task->running);
1598 conn->task->state = ISCSI_TASK_RUNNING;
1599 spin_unlock_bh(&conn->taskqueuelock);
1600 rc = iscsi_xmit_task(conn);
1601 if (rc)
1602 goto done;
1603 spin_lock_bh(&conn->taskqueuelock);
1604 if (!list_empty(&conn->mgmtqueue))
1605 goto check_mgmt;
1606 }
1607 spin_unlock_bh(&conn->taskqueuelock);
1608 spin_unlock_bh(&conn->session->frwd_lock);
1609 return -ENODATA;
1610
1611done:
1612 spin_unlock_bh(&conn->session->frwd_lock);
1613 return rc;
1614}
1615
1616static void iscsi_xmitworker(struct work_struct *work)
1617{
1618 struct iscsi_conn *conn =
1619 container_of(work, struct iscsi_conn, xmitwork);
1620 int rc;
1621 /*
1622 * serialize Xmit worker on a per-connection basis.
1623 */
1624 do {
1625 rc = iscsi_data_xmit(conn);
1626 } while (rc >= 0 || rc == -EAGAIN);
1627}
1628
1629static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1630 struct scsi_cmnd *sc)
1631{
1632 struct iscsi_task *task;
1633
1634 if (!kfifo_out(&conn->session->cmdpool.queue,
1635 (void *) &task, sizeof(void *)))
1636 return NULL;
1637
1638 sc->SCp.phase = conn->session->age;
1639 sc->SCp.ptr = (char *) task;
1640
1641 refcount_set(&task->refcount, 1);
1642 task->state = ISCSI_TASK_PENDING;
1643 task->conn = conn;
1644 task->sc = sc;
1645 task->have_checked_conn = false;
1646 task->last_timeout = jiffies;
1647 task->last_xfer = jiffies;
1648 task->protected = false;
1649 INIT_LIST_HEAD(&task->running);
1650 return task;
1651}
1652
1653enum {
1654 FAILURE_BAD_HOST = 1,
1655 FAILURE_SESSION_FAILED,
1656 FAILURE_SESSION_FREED,
1657 FAILURE_WINDOW_CLOSED,
1658 FAILURE_OOM,
1659 FAILURE_SESSION_TERMINATE,
1660 FAILURE_SESSION_IN_RECOVERY,
1661 FAILURE_SESSION_RECOVERY_TIMEOUT,
1662 FAILURE_SESSION_LOGGING_OUT,
1663 FAILURE_SESSION_NOT_READY,
1664};
1665
1666int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1667{
1668 struct iscsi_cls_session *cls_session;
1669 struct iscsi_host *ihost;
1670 int reason = 0;
1671 struct iscsi_session *session;
1672 struct iscsi_conn *conn;
1673 struct iscsi_task *task = NULL;
1674
1675 sc->result = 0;
1676 sc->SCp.ptr = NULL;
1677
1678 ihost = shost_priv(host);
1679
1680 cls_session = starget_to_session(scsi_target(sc->device));
1681 session = cls_session->dd_data;
1682 spin_lock_bh(&session->frwd_lock);
1683
1684 reason = iscsi_session_chkready(cls_session);
1685 if (reason) {
1686 sc->result = reason;
1687 goto fault;
1688 }
1689
1690 if (session->state != ISCSI_STATE_LOGGED_IN) {
1691 /*
1692 * to handle the race between when we set the recovery state
1693 * and block the session we requeue here (commands could
1694 * be entering our queuecommand while a block is starting
1695 * up because the block code is not locked)
1696 */
1697 switch (session->state) {
1698 case ISCSI_STATE_FAILED:
1699 /*
1700 * cmds should fail during shutdown, if the session
1701 * state is bad, allowing completion to happen
1702 */
1703 if (unlikely(system_state != SYSTEM_RUNNING)) {
1704 reason = FAILURE_SESSION_FAILED;
1705 sc->result = DID_NO_CONNECT << 16;
1706 break;
1707 }
1708 case ISCSI_STATE_IN_RECOVERY:
1709 reason = FAILURE_SESSION_IN_RECOVERY;
1710 sc->result = DID_IMM_RETRY << 16;
1711 break;
1712 case ISCSI_STATE_LOGGING_OUT:
1713 reason = FAILURE_SESSION_LOGGING_OUT;
1714 sc->result = DID_IMM_RETRY << 16;
1715 break;
1716 case ISCSI_STATE_RECOVERY_FAILED:
1717 reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1718 sc->result = DID_TRANSPORT_FAILFAST << 16;
1719 break;
1720 case ISCSI_STATE_TERMINATE:
1721 reason = FAILURE_SESSION_TERMINATE;
1722 sc->result = DID_NO_CONNECT << 16;
1723 break;
1724 default:
1725 reason = FAILURE_SESSION_FREED;
1726 sc->result = DID_NO_CONNECT << 16;
1727 }
1728 goto fault;
1729 }
1730
1731 conn = session->leadconn;
1732 if (!conn) {
1733 reason = FAILURE_SESSION_FREED;
1734 sc->result = DID_NO_CONNECT << 16;
1735 goto fault;
1736 }
1737
1738 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1739 reason = FAILURE_SESSION_IN_RECOVERY;
1740 sc->result = DID_REQUEUE << 16;
1741 goto fault;
1742 }
1743
1744 if (iscsi_check_cmdsn_window_closed(conn)) {
1745 reason = FAILURE_WINDOW_CLOSED;
1746 goto reject;
1747 }
1748
1749 task = iscsi_alloc_task(conn, sc);
1750 if (!task) {
1751 reason = FAILURE_OOM;
1752 goto reject;
1753 }
1754
1755 if (!ihost->workq) {
1756 reason = iscsi_prep_scsi_cmd_pdu(task);
1757 if (reason) {
1758 if (reason == -ENOMEM || reason == -EACCES) {
1759 reason = FAILURE_OOM;
1760 goto prepd_reject;
1761 } else {
1762 sc->result = DID_ABORT << 16;
1763 goto prepd_fault;
1764 }
1765 }
1766 if (session->tt->xmit_task(task)) {
1767 session->cmdsn--;
1768 reason = FAILURE_SESSION_NOT_READY;
1769 goto prepd_reject;
1770 }
1771 } else {
1772 spin_lock_bh(&conn->taskqueuelock);
1773 list_add_tail(&task->running, &conn->cmdqueue);
1774 spin_unlock_bh(&conn->taskqueuelock);
1775 iscsi_conn_queue_work(conn);
1776 }
1777
1778 session->queued_cmdsn++;
1779 spin_unlock_bh(&session->frwd_lock);
1780 return 0;
1781
1782prepd_reject:
1783 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1784reject:
1785 spin_unlock_bh(&session->frwd_lock);
1786 ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1787 sc->cmnd[0], reason);
1788 return SCSI_MLQUEUE_TARGET_BUSY;
1789
1790prepd_fault:
1791 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1792fault:
1793 spin_unlock_bh(&session->frwd_lock);
1794 ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1795 sc->cmnd[0], reason);
1796 if (!scsi_bidi_cmnd(sc))
1797 scsi_set_resid(sc, scsi_bufflen(sc));
1798 else {
1799 scsi_out(sc)->resid = scsi_out(sc)->length;
1800 scsi_in(sc)->resid = scsi_in(sc)->length;
1801 }
1802 sc->scsi_done(sc);
1803 return 0;
1804}
1805EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1806
1807int iscsi_target_alloc(struct scsi_target *starget)
1808{
1809 struct iscsi_cls_session *cls_session = starget_to_session(starget);
1810 struct iscsi_session *session = cls_session->dd_data;
1811
1812 starget->can_queue = session->scsi_cmds_max;
1813 return 0;
1814}
1815EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1816
1817static void iscsi_tmf_timedout(struct timer_list *t)
1818{
1819 struct iscsi_conn *conn = from_timer(conn, t, tmf_timer);
1820 struct iscsi_session *session = conn->session;
1821
1822 spin_lock(&session->frwd_lock);
1823 if (conn->tmf_state == TMF_QUEUED) {
1824 conn->tmf_state = TMF_TIMEDOUT;
1825 ISCSI_DBG_EH(session, "tmf timedout\n");
1826 /* unblock eh_abort() */
1827 wake_up(&conn->ehwait);
1828 }
1829 spin_unlock(&session->frwd_lock);
1830}
1831
1832static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1833 struct iscsi_tm *hdr, int age,
1834 int timeout)
1835{
1836 struct iscsi_session *session = conn->session;
1837 struct iscsi_task *task;
1838
1839 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1840 NULL, 0);
1841 if (!task) {
1842 spin_unlock_bh(&session->frwd_lock);
1843 iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1844 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1845 spin_lock_bh(&session->frwd_lock);
1846 return -EPERM;
1847 }
1848 conn->tmfcmd_pdus_cnt++;
1849 conn->tmf_timer.expires = timeout * HZ + jiffies;
1850 add_timer(&conn->tmf_timer);
1851 ISCSI_DBG_EH(session, "tmf set timeout\n");
1852
1853 spin_unlock_bh(&session->frwd_lock);
1854 mutex_unlock(&session->eh_mutex);
1855
1856 /*
1857 * block eh thread until:
1858 *
1859 * 1) tmf response
1860 * 2) tmf timeout
1861 * 3) session is terminated or restarted or userspace has
1862 * given up on recovery
1863 */
1864 wait_event_interruptible(conn->ehwait, age != session->age ||
1865 session->state != ISCSI_STATE_LOGGED_IN ||
1866 conn->tmf_state != TMF_QUEUED);
1867 if (signal_pending(current))
1868 flush_signals(current);
1869 del_timer_sync(&conn->tmf_timer);
1870
1871 mutex_lock(&session->eh_mutex);
1872 spin_lock_bh(&session->frwd_lock);
1873 /* if the session drops it will clean up the task */
1874 if (age != session->age ||
1875 session->state != ISCSI_STATE_LOGGED_IN)
1876 return -ENOTCONN;
1877 return 0;
1878}
1879
1880/*
1881 * Fail commands. session lock held and recv side suspended and xmit
1882 * thread flushed
1883 */
1884static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error)
1885{
1886 struct iscsi_task *task;
1887 int i;
1888
1889 for (i = 0; i < conn->session->cmds_max; i++) {
1890 task = conn->session->cmds[i];
1891 if (!task->sc || task->state == ISCSI_TASK_FREE)
1892 continue;
1893
1894 if (lun != -1 && lun != task->sc->device->lun)
1895 continue;
1896
1897 ISCSI_DBG_SESSION(conn->session,
1898 "failing sc %p itt 0x%x state %d\n",
1899 task->sc, task->itt, task->state);
1900 fail_scsi_task(task, error);
1901 }
1902}
1903
1904/**
1905 * iscsi_suspend_queue - suspend iscsi_queuecommand
1906 * @conn: iscsi conn to stop queueing IO on
1907 *
1908 * This grabs the session frwd_lock to make sure no one is in
1909 * xmit_task/queuecommand, and then sets suspend to prevent
1910 * new commands from being queued. This only needs to be called
1911 * by offload drivers that need to sync a path like ep disconnect
1912 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1913 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1914 */
1915void iscsi_suspend_queue(struct iscsi_conn *conn)
1916{
1917 spin_lock_bh(&conn->session->frwd_lock);
1918 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1919 spin_unlock_bh(&conn->session->frwd_lock);
1920}
1921EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1922
1923/**
1924 * iscsi_suspend_tx - suspend iscsi_data_xmit
1925 * @conn: iscsi conn tp stop processing IO on.
1926 *
1927 * This function sets the suspend bit to prevent iscsi_data_xmit
1928 * from sending new IO, and if work is queued on the xmit thread
1929 * it will wait for it to be completed.
1930 */
1931void iscsi_suspend_tx(struct iscsi_conn *conn)
1932{
1933 struct Scsi_Host *shost = conn->session->host;
1934 struct iscsi_host *ihost = shost_priv(shost);
1935
1936 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1937 if (ihost->workq)
1938 flush_workqueue(ihost->workq);
1939}
1940EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1941
1942static void iscsi_start_tx(struct iscsi_conn *conn)
1943{
1944 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1945 iscsi_conn_queue_work(conn);
1946}
1947
1948/*
1949 * We want to make sure a ping is in flight. It has timed out.
1950 * And we are not busy processing a pdu that is making
1951 * progress but got started before the ping and is taking a while
1952 * to complete so the ping is just stuck behind it in a queue.
1953 */
1954static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1955{
1956 if (conn->ping_task &&
1957 time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1958 (conn->ping_timeout * HZ), jiffies))
1959 return 1;
1960 else
1961 return 0;
1962}
1963
1964enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1965{
1966 enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
1967 struct iscsi_task *task = NULL, *running_task;
1968 struct iscsi_cls_session *cls_session;
1969 struct iscsi_session *session;
1970 struct iscsi_conn *conn;
1971 int i;
1972
1973 cls_session = starget_to_session(scsi_target(sc->device));
1974 session = cls_session->dd_data;
1975
1976 ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1977
1978 spin_lock(&session->frwd_lock);
1979 task = (struct iscsi_task *)sc->SCp.ptr;
1980 if (!task) {
1981 /*
1982 * Raced with completion. Blk layer has taken ownership
1983 * so let timeout code complete it now.
1984 */
1985 rc = BLK_EH_HANDLED;
1986 goto done;
1987 }
1988
1989 if (session->state != ISCSI_STATE_LOGGED_IN) {
1990 /*
1991 * During shutdown, if session is prematurely disconnected,
1992 * recovery won't happen and there will be hung cmds. Not
1993 * handling cmds would trigger EH, also bad in this case.
1994 * Instead, handle cmd, allow completion to happen and let
1995 * upper layer to deal with the result.
1996 */
1997 if (unlikely(system_state != SYSTEM_RUNNING)) {
1998 sc->result = DID_NO_CONNECT << 16;
1999 ISCSI_DBG_EH(session, "sc on shutdown, handled\n");
2000 rc = BLK_EH_HANDLED;
2001 goto done;
2002 }
2003 /*
2004 * We are probably in the middle of iscsi recovery so let
2005 * that complete and handle the error.
2006 */
2007 rc = BLK_EH_RESET_TIMER;
2008 goto done;
2009 }
2010
2011 conn = session->leadconn;
2012 if (!conn) {
2013 /* In the middle of shuting down */
2014 rc = BLK_EH_RESET_TIMER;
2015 goto done;
2016 }
2017
2018 /*
2019 * If we have sent (at least queued to the network layer) a pdu or
2020 * recvd one for the task since the last timeout ask for
2021 * more time. If on the next timeout we have not made progress
2022 * we can check if it is the task or connection when we send the
2023 * nop as a ping.
2024 */
2025 if (time_after(task->last_xfer, task->last_timeout)) {
2026 ISCSI_DBG_EH(session, "Command making progress. Asking "
2027 "scsi-ml for more time to complete. "
2028 "Last data xfer at %lu. Last timeout was at "
2029 "%lu\n.", task->last_xfer, task->last_timeout);
2030 task->have_checked_conn = false;
2031 rc = BLK_EH_RESET_TIMER;
2032 goto done;
2033 }
2034
2035 if (!conn->recv_timeout && !conn->ping_timeout)
2036 goto done;
2037 /*
2038 * if the ping timedout then we are in the middle of cleaning up
2039 * and can let the iscsi eh handle it
2040 */
2041 if (iscsi_has_ping_timed_out(conn)) {
2042 rc = BLK_EH_RESET_TIMER;
2043 goto done;
2044 }
2045
2046 for (i = 0; i < conn->session->cmds_max; i++) {
2047 running_task = conn->session->cmds[i];
2048 if (!running_task->sc || running_task == task ||
2049 running_task->state != ISCSI_TASK_RUNNING)
2050 continue;
2051
2052 /*
2053 * Only check if cmds started before this one have made
2054 * progress, or this could never fail
2055 */
2056 if (time_after(running_task->sc->jiffies_at_alloc,
2057 task->sc->jiffies_at_alloc))
2058 continue;
2059
2060 if (time_after(running_task->last_xfer, task->last_timeout)) {
2061 /*
2062 * This task has not made progress, but a task
2063 * started before us has transferred data since
2064 * we started/last-checked. We could be queueing
2065 * too many tasks or the LU is bad.
2066 *
2067 * If the device is bad the cmds ahead of us on
2068 * other devs will complete, and this loop will
2069 * eventually fail starting the scsi eh.
2070 */
2071 ISCSI_DBG_EH(session, "Command has not made progress "
2072 "but commands ahead of it have. "
2073 "Asking scsi-ml for more time to "
2074 "complete. Our last xfer vs running task "
2075 "last xfer %lu/%lu. Last check %lu.\n",
2076 task->last_xfer, running_task->last_xfer,
2077 task->last_timeout);
2078 rc = BLK_EH_RESET_TIMER;
2079 goto done;
2080 }
2081 }
2082
2083 /* Assumes nop timeout is shorter than scsi cmd timeout */
2084 if (task->have_checked_conn)
2085 goto done;
2086
2087 /*
2088 * Checking the transport already or nop from a cmd timeout still
2089 * running
2090 */
2091 if (conn->ping_task) {
2092 task->have_checked_conn = true;
2093 rc = BLK_EH_RESET_TIMER;
2094 goto done;
2095 }
2096
2097 /* Make sure there is a transport check done */
2098 iscsi_send_nopout(conn, NULL);
2099 task->have_checked_conn = true;
2100 rc = BLK_EH_RESET_TIMER;
2101
2102done:
2103 if (task)
2104 task->last_timeout = jiffies;
2105 spin_unlock(&session->frwd_lock);
2106 ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2107 "timer reset" : "shutdown or nh");
2108 return rc;
2109}
2110EXPORT_SYMBOL_GPL(iscsi_eh_cmd_timed_out);
2111
2112static void iscsi_check_transport_timeouts(struct timer_list *t)
2113{
2114 struct iscsi_conn *conn = from_timer(conn, t, transport_timer);
2115 struct iscsi_session *session = conn->session;
2116 unsigned long recv_timeout, next_timeout = 0, last_recv;
2117
2118 spin_lock(&session->frwd_lock);
2119 if (session->state != ISCSI_STATE_LOGGED_IN)
2120 goto done;
2121
2122 recv_timeout = conn->recv_timeout;
2123 if (!recv_timeout)
2124 goto done;
2125
2126 recv_timeout *= HZ;
2127 last_recv = conn->last_recv;
2128
2129 if (iscsi_has_ping_timed_out(conn)) {
2130 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2131 "expired, recv timeout %d, last rx %lu, "
2132 "last ping %lu, now %lu\n",
2133 conn->ping_timeout, conn->recv_timeout,
2134 last_recv, conn->last_ping, jiffies);
2135 spin_unlock(&session->frwd_lock);
2136 iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT);
2137 return;
2138 }
2139
2140 if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2141 /* send a ping to try to provoke some traffic */
2142 ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2143 if (iscsi_send_nopout(conn, NULL))
2144 next_timeout = jiffies + (1 * HZ);
2145 else
2146 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2147 } else
2148 next_timeout = last_recv + recv_timeout;
2149
2150 ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2151 mod_timer(&conn->transport_timer, next_timeout);
2152done:
2153 spin_unlock(&session->frwd_lock);
2154}
2155
2156static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2157 struct iscsi_tm *hdr)
2158{
2159 memset(hdr, 0, sizeof(*hdr));
2160 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2161 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2162 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2163 hdr->lun = task->lun;
2164 hdr->rtt = task->hdr_itt;
2165 hdr->refcmdsn = task->cmdsn;
2166}
2167
2168int iscsi_eh_abort(struct scsi_cmnd *sc)
2169{
2170 struct iscsi_cls_session *cls_session;
2171 struct iscsi_session *session;
2172 struct iscsi_conn *conn;
2173 struct iscsi_task *task;
2174 struct iscsi_tm *hdr;
2175 int age;
2176
2177 cls_session = starget_to_session(scsi_target(sc->device));
2178 session = cls_session->dd_data;
2179
2180 ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2181
2182 mutex_lock(&session->eh_mutex);
2183 spin_lock_bh(&session->frwd_lock);
2184 /*
2185 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2186 * got the command.
2187 */
2188 if (!sc->SCp.ptr) {
2189 ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2190 "it completed.\n");
2191 spin_unlock_bh(&session->frwd_lock);
2192 mutex_unlock(&session->eh_mutex);
2193 return SUCCESS;
2194 }
2195
2196 /*
2197 * If we are not logged in or we have started a new session
2198 * then let the host reset code handle this
2199 */
2200 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2201 sc->SCp.phase != session->age) {
2202 spin_unlock_bh(&session->frwd_lock);
2203 mutex_unlock(&session->eh_mutex);
2204 ISCSI_DBG_EH(session, "failing abort due to dropped "
2205 "session.\n");
2206 return FAILED;
2207 }
2208
2209 conn = session->leadconn;
2210 conn->eh_abort_cnt++;
2211 age = session->age;
2212
2213 task = (struct iscsi_task *)sc->SCp.ptr;
2214 ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
2215 sc, task->itt);
2216
2217 /* task completed before time out */
2218 if (!task->sc) {
2219 ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2220 goto success;
2221 }
2222
2223 if (task->state == ISCSI_TASK_PENDING) {
2224 fail_scsi_task(task, DID_ABORT);
2225 goto success;
2226 }
2227
2228 /* only have one tmf outstanding at a time */
2229 if (conn->tmf_state != TMF_INITIAL)
2230 goto failed;
2231 conn->tmf_state = TMF_QUEUED;
2232
2233 hdr = &conn->tmhdr;
2234 iscsi_prep_abort_task_pdu(task, hdr);
2235
2236 if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout))
2237 goto failed;
2238
2239 switch (conn->tmf_state) {
2240 case TMF_SUCCESS:
2241 spin_unlock_bh(&session->frwd_lock);
2242 /*
2243 * stop tx side incase the target had sent a abort rsp but
2244 * the initiator was still writing out data.
2245 */
2246 iscsi_suspend_tx(conn);
2247 /*
2248 * we do not stop the recv side because targets have been
2249 * good and have never sent us a successful tmf response
2250 * then sent more data for the cmd.
2251 */
2252 spin_lock_bh(&session->frwd_lock);
2253 fail_scsi_task(task, DID_ABORT);
2254 conn->tmf_state = TMF_INITIAL;
2255 memset(hdr, 0, sizeof(*hdr));
2256 spin_unlock_bh(&session->frwd_lock);
2257 iscsi_start_tx(conn);
2258 goto success_unlocked;
2259 case TMF_TIMEDOUT:
2260 spin_unlock_bh(&session->frwd_lock);
2261 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2262 goto failed_unlocked;
2263 case TMF_NOT_FOUND:
2264 if (!sc->SCp.ptr) {
2265 conn->tmf_state = TMF_INITIAL;
2266 memset(hdr, 0, sizeof(*hdr));
2267 /* task completed before tmf abort response */
2268 ISCSI_DBG_EH(session, "sc completed while abort in "
2269 "progress\n");
2270 goto success;
2271 }
2272 /* fall through */
2273 default:
2274 conn->tmf_state = TMF_INITIAL;
2275 goto failed;
2276 }
2277
2278success:
2279 spin_unlock_bh(&session->frwd_lock);
2280success_unlocked:
2281 ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2282 sc, task->itt);
2283 mutex_unlock(&session->eh_mutex);
2284 return SUCCESS;
2285
2286failed:
2287 spin_unlock_bh(&session->frwd_lock);
2288failed_unlocked:
2289 ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2290 task ? task->itt : 0);
2291 mutex_unlock(&session->eh_mutex);
2292 return FAILED;
2293}
2294EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2295
2296static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2297{
2298 memset(hdr, 0, sizeof(*hdr));
2299 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2300 hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2301 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2302 int_to_scsilun(sc->device->lun, &hdr->lun);
2303 hdr->rtt = RESERVED_ITT;
2304}
2305
2306int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2307{
2308 struct iscsi_cls_session *cls_session;
2309 struct iscsi_session *session;
2310 struct iscsi_conn *conn;
2311 struct iscsi_tm *hdr;
2312 int rc = FAILED;
2313
2314 cls_session = starget_to_session(scsi_target(sc->device));
2315 session = cls_session->dd_data;
2316
2317 ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc,
2318 sc->device->lun);
2319
2320 mutex_lock(&session->eh_mutex);
2321 spin_lock_bh(&session->frwd_lock);
2322 /*
2323 * Just check if we are not logged in. We cannot check for
2324 * the phase because the reset could come from a ioctl.
2325 */
2326 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2327 goto unlock;
2328 conn = session->leadconn;
2329
2330 /* only have one tmf outstanding at a time */
2331 if (conn->tmf_state != TMF_INITIAL)
2332 goto unlock;
2333 conn->tmf_state = TMF_QUEUED;
2334
2335 hdr = &conn->tmhdr;
2336 iscsi_prep_lun_reset_pdu(sc, hdr);
2337
2338 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2339 session->lu_reset_timeout)) {
2340 rc = FAILED;
2341 goto unlock;
2342 }
2343
2344 switch (conn->tmf_state) {
2345 case TMF_SUCCESS:
2346 break;
2347 case TMF_TIMEDOUT:
2348 spin_unlock_bh(&session->frwd_lock);
2349 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2350 goto done;
2351 default:
2352 conn->tmf_state = TMF_INITIAL;
2353 goto unlock;
2354 }
2355
2356 rc = SUCCESS;
2357 spin_unlock_bh(&session->frwd_lock);
2358
2359 iscsi_suspend_tx(conn);
2360
2361 spin_lock_bh(&session->frwd_lock);
2362 memset(hdr, 0, sizeof(*hdr));
2363 fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2364 conn->tmf_state = TMF_INITIAL;
2365 spin_unlock_bh(&session->frwd_lock);
2366
2367 iscsi_start_tx(conn);
2368 goto done;
2369
2370unlock:
2371 spin_unlock_bh(&session->frwd_lock);
2372done:
2373 ISCSI_DBG_EH(session, "dev reset result = %s\n",
2374 rc == SUCCESS ? "SUCCESS" : "FAILED");
2375 mutex_unlock(&session->eh_mutex);
2376 return rc;
2377}
2378EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2379
2380void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2381{
2382 struct iscsi_session *session = cls_session->dd_data;
2383
2384 spin_lock_bh(&session->frwd_lock);
2385 if (session->state != ISCSI_STATE_LOGGED_IN) {
2386 session->state = ISCSI_STATE_RECOVERY_FAILED;
2387 if (session->leadconn)
2388 wake_up(&session->leadconn->ehwait);
2389 }
2390 spin_unlock_bh(&session->frwd_lock);
2391}
2392EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2393
2394/**
2395 * iscsi_eh_session_reset - drop session and attempt relogin
2396 * @sc: scsi command
2397 *
2398 * This function will wait for a relogin, session termination from
2399 * userspace, or a recovery/replacement timeout.
2400 */
2401int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2402{
2403 struct iscsi_cls_session *cls_session;
2404 struct iscsi_session *session;
2405 struct iscsi_conn *conn;
2406
2407 cls_session = starget_to_session(scsi_target(sc->device));
2408 session = cls_session->dd_data;
2409 conn = session->leadconn;
2410
2411 mutex_lock(&session->eh_mutex);
2412 spin_lock_bh(&session->frwd_lock);
2413 if (session->state == ISCSI_STATE_TERMINATE) {
2414failed:
2415 ISCSI_DBG_EH(session,
2416 "failing session reset: Could not log back into "
2417 "%s, %s [age %d]\n", session->targetname,
2418 conn->persistent_address, session->age);
2419 spin_unlock_bh(&session->frwd_lock);
2420 mutex_unlock(&session->eh_mutex);
2421 return FAILED;
2422 }
2423
2424 spin_unlock_bh(&session->frwd_lock);
2425 mutex_unlock(&session->eh_mutex);
2426 /*
2427 * we drop the lock here but the leadconn cannot be destoyed while
2428 * we are in the scsi eh
2429 */
2430 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2431
2432 ISCSI_DBG_EH(session, "wait for relogin\n");
2433 wait_event_interruptible(conn->ehwait,
2434 session->state == ISCSI_STATE_TERMINATE ||
2435 session->state == ISCSI_STATE_LOGGED_IN ||
2436 session->state == ISCSI_STATE_RECOVERY_FAILED);
2437 if (signal_pending(current))
2438 flush_signals(current);
2439
2440 mutex_lock(&session->eh_mutex);
2441 spin_lock_bh(&session->frwd_lock);
2442 if (session->state == ISCSI_STATE_LOGGED_IN) {
2443 ISCSI_DBG_EH(session,
2444 "session reset succeeded for %s,%s\n",
2445 session->targetname, conn->persistent_address);
2446 } else
2447 goto failed;
2448 spin_unlock_bh(&session->frwd_lock);
2449 mutex_unlock(&session->eh_mutex);
2450 return SUCCESS;
2451}
2452EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2453
2454static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2455{
2456 memset(hdr, 0, sizeof(*hdr));
2457 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2458 hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2459 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2460 hdr->rtt = RESERVED_ITT;
2461}
2462
2463/**
2464 * iscsi_eh_target_reset - reset target
2465 * @sc: scsi command
2466 *
2467 * This will attempt to send a warm target reset.
2468 */
2469static int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2470{
2471 struct iscsi_cls_session *cls_session;
2472 struct iscsi_session *session;
2473 struct iscsi_conn *conn;
2474 struct iscsi_tm *hdr;
2475 int rc = FAILED;
2476
2477 cls_session = starget_to_session(scsi_target(sc->device));
2478 session = cls_session->dd_data;
2479
2480 ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2481 session->targetname);
2482
2483 mutex_lock(&session->eh_mutex);
2484 spin_lock_bh(&session->frwd_lock);
2485 /*
2486 * Just check if we are not logged in. We cannot check for
2487 * the phase because the reset could come from a ioctl.
2488 */
2489 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2490 goto unlock;
2491 conn = session->leadconn;
2492
2493 /* only have one tmf outstanding at a time */
2494 if (conn->tmf_state != TMF_INITIAL)
2495 goto unlock;
2496 conn->tmf_state = TMF_QUEUED;
2497
2498 hdr = &conn->tmhdr;
2499 iscsi_prep_tgt_reset_pdu(sc, hdr);
2500
2501 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2502 session->tgt_reset_timeout)) {
2503 rc = FAILED;
2504 goto unlock;
2505 }
2506
2507 switch (conn->tmf_state) {
2508 case TMF_SUCCESS:
2509 break;
2510 case TMF_TIMEDOUT:
2511 spin_unlock_bh(&session->frwd_lock);
2512 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2513 goto done;
2514 default:
2515 conn->tmf_state = TMF_INITIAL;
2516 goto unlock;
2517 }
2518
2519 rc = SUCCESS;
2520 spin_unlock_bh(&session->frwd_lock);
2521
2522 iscsi_suspend_tx(conn);
2523
2524 spin_lock_bh(&session->frwd_lock);
2525 memset(hdr, 0, sizeof(*hdr));
2526 fail_scsi_tasks(conn, -1, DID_ERROR);
2527 conn->tmf_state = TMF_INITIAL;
2528 spin_unlock_bh(&session->frwd_lock);
2529
2530 iscsi_start_tx(conn);
2531 goto done;
2532
2533unlock:
2534 spin_unlock_bh(&session->frwd_lock);
2535done:
2536 ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2537 rc == SUCCESS ? "SUCCESS" : "FAILED");
2538 mutex_unlock(&session->eh_mutex);
2539 return rc;
2540}
2541
2542/**
2543 * iscsi_eh_recover_target - reset target and possibly the session
2544 * @sc: scsi command
2545 *
2546 * This will attempt to send a warm target reset. If that fails,
2547 * we will escalate to ERL0 session recovery.
2548 */
2549int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2550{
2551 int rc;
2552
2553 rc = iscsi_eh_target_reset(sc);
2554 if (rc == FAILED)
2555 rc = iscsi_eh_session_reset(sc);
2556 return rc;
2557}
2558EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2559
2560/*
2561 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2562 * should be accessed via kfifo_{get,put} on q->queue.
2563 * Optionally, the caller can obtain the array of object pointers
2564 * by passing in a non-NULL @items pointer
2565 */
2566int
2567iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2568{
2569 int i, num_arrays = 1;
2570
2571 memset(q, 0, sizeof(*q));
2572
2573 q->max = max;
2574
2575 /* If the user passed an items pointer, he wants a copy of
2576 * the array. */
2577 if (items)
2578 num_arrays++;
2579 q->pool = kvzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
2580 if (q->pool == NULL)
2581 return -ENOMEM;
2582
2583 kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2584
2585 for (i = 0; i < max; i++) {
2586 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2587 if (q->pool[i] == NULL) {
2588 q->max = i;
2589 goto enomem;
2590 }
2591 kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2592 }
2593
2594 if (items) {
2595 *items = q->pool + max;
2596 memcpy(*items, q->pool, max * sizeof(void *));
2597 }
2598
2599 return 0;
2600
2601enomem:
2602 iscsi_pool_free(q);
2603 return -ENOMEM;
2604}
2605EXPORT_SYMBOL_GPL(iscsi_pool_init);
2606
2607void iscsi_pool_free(struct iscsi_pool *q)
2608{
2609 int i;
2610
2611 for (i = 0; i < q->max; i++)
2612 kfree(q->pool[i]);
2613 kvfree(q->pool);
2614}
2615EXPORT_SYMBOL_GPL(iscsi_pool_free);
2616
2617/**
2618 * iscsi_host_add - add host to system
2619 * @shost: scsi host
2620 * @pdev: parent device
2621 *
2622 * This should be called by partial offload and software iscsi drivers
2623 * to add a host to the system.
2624 */
2625int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2626{
2627 if (!shost->can_queue)
2628 shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2629
2630 if (!shost->cmd_per_lun)
2631 shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2632
2633 return scsi_add_host(shost, pdev);
2634}
2635EXPORT_SYMBOL_GPL(iscsi_host_add);
2636
2637/**
2638 * iscsi_host_alloc - allocate a host and driver data
2639 * @sht: scsi host template
2640 * @dd_data_size: driver host data size
2641 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2642 *
2643 * This should be called by partial offload and software iscsi drivers.
2644 * To access the driver specific memory use the iscsi_host_priv() macro.
2645 */
2646struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2647 int dd_data_size, bool xmit_can_sleep)
2648{
2649 struct Scsi_Host *shost;
2650 struct iscsi_host *ihost;
2651
2652 shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2653 if (!shost)
2654 return NULL;
2655 ihost = shost_priv(shost);
2656
2657 if (xmit_can_sleep) {
2658 snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2659 "iscsi_q_%d", shost->host_no);
2660 ihost->workq = create_singlethread_workqueue(ihost->workq_name);
2661 if (!ihost->workq)
2662 goto free_host;
2663 }
2664
2665 spin_lock_init(&ihost->lock);
2666 ihost->state = ISCSI_HOST_SETUP;
2667 ihost->num_sessions = 0;
2668 init_waitqueue_head(&ihost->session_removal_wq);
2669 return shost;
2670
2671free_host:
2672 scsi_host_put(shost);
2673 return NULL;
2674}
2675EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2676
2677static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2678{
2679 iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2680}
2681
2682/**
2683 * iscsi_host_remove - remove host and sessions
2684 * @shost: scsi host
2685 *
2686 * If there are any sessions left, this will initiate the removal and wait
2687 * for the completion.
2688 */
2689void iscsi_host_remove(struct Scsi_Host *shost)
2690{
2691 struct iscsi_host *ihost = shost_priv(shost);
2692 unsigned long flags;
2693
2694 spin_lock_irqsave(&ihost->lock, flags);
2695 ihost->state = ISCSI_HOST_REMOVED;
2696 spin_unlock_irqrestore(&ihost->lock, flags);
2697
2698 iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2699 wait_event_interruptible(ihost->session_removal_wq,
2700 ihost->num_sessions == 0);
2701 if (signal_pending(current))
2702 flush_signals(current);
2703
2704 scsi_remove_host(shost);
2705 if (ihost->workq)
2706 destroy_workqueue(ihost->workq);
2707}
2708EXPORT_SYMBOL_GPL(iscsi_host_remove);
2709
2710void iscsi_host_free(struct Scsi_Host *shost)
2711{
2712 struct iscsi_host *ihost = shost_priv(shost);
2713
2714 kfree(ihost->netdev);
2715 kfree(ihost->hwaddress);
2716 kfree(ihost->initiatorname);
2717 scsi_host_put(shost);
2718}
2719EXPORT_SYMBOL_GPL(iscsi_host_free);
2720
2721static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2722{
2723 struct iscsi_host *ihost = shost_priv(shost);
2724 unsigned long flags;
2725
2726 shost = scsi_host_get(shost);
2727 if (!shost) {
2728 printk(KERN_ERR "Invalid state. Cannot notify host removal "
2729 "of session teardown event because host already "
2730 "removed.\n");
2731 return;
2732 }
2733
2734 spin_lock_irqsave(&ihost->lock, flags);
2735 ihost->num_sessions--;
2736 if (ihost->num_sessions == 0)
2737 wake_up(&ihost->session_removal_wq);
2738 spin_unlock_irqrestore(&ihost->lock, flags);
2739 scsi_host_put(shost);
2740}
2741
2742/**
2743 * iscsi_session_setup - create iscsi cls session and host and session
2744 * @iscsit: iscsi transport template
2745 * @shost: scsi host
2746 * @cmds_max: session can queue
2747 * @dd_size: private driver data size, added to session allocation size
2748 * @cmd_task_size: LLD task private data size
2749 * @initial_cmdsn: initial CmdSN
2750 * @id: target ID to add to this session
2751 *
2752 * This can be used by software iscsi_transports that allocate
2753 * a session per scsi host.
2754 *
2755 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2756 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2757 * for nop handling and login/logout requests.
2758 */
2759struct iscsi_cls_session *
2760iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2761 uint16_t cmds_max, int dd_size, int cmd_task_size,
2762 uint32_t initial_cmdsn, unsigned int id)
2763{
2764 struct iscsi_host *ihost = shost_priv(shost);
2765 struct iscsi_session *session;
2766 struct iscsi_cls_session *cls_session;
2767 int cmd_i, scsi_cmds, total_cmds = cmds_max;
2768 unsigned long flags;
2769
2770 spin_lock_irqsave(&ihost->lock, flags);
2771 if (ihost->state == ISCSI_HOST_REMOVED) {
2772 spin_unlock_irqrestore(&ihost->lock, flags);
2773 return NULL;
2774 }
2775 ihost->num_sessions++;
2776 spin_unlock_irqrestore(&ihost->lock, flags);
2777
2778 if (!total_cmds)
2779 total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2780 /*
2781 * The iscsi layer needs some tasks for nop handling and tmfs,
2782 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2783 * + 1 command for scsi IO.
2784 */
2785 if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2786 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2787 "must be a power of two that is at least %d.\n",
2788 total_cmds, ISCSI_TOTAL_CMDS_MIN);
2789 goto dec_session_count;
2790 }
2791
2792 if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2793 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2794 "must be a power of 2 less than or equal to %d.\n",
2795 cmds_max, ISCSI_TOTAL_CMDS_MAX);
2796 total_cmds = ISCSI_TOTAL_CMDS_MAX;
2797 }
2798
2799 if (!is_power_of_2(total_cmds)) {
2800 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2801 "must be a power of 2.\n", total_cmds);
2802 total_cmds = rounddown_pow_of_two(total_cmds);
2803 if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
2804 return NULL;
2805 printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
2806 total_cmds);
2807 }
2808 scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2809
2810 cls_session = iscsi_alloc_session(shost, iscsit,
2811 sizeof(struct iscsi_session) +
2812 dd_size);
2813 if (!cls_session)
2814 goto dec_session_count;
2815 session = cls_session->dd_data;
2816 session->cls_session = cls_session;
2817 session->host = shost;
2818 session->state = ISCSI_STATE_FREE;
2819 session->fast_abort = 1;
2820 session->tgt_reset_timeout = 30;
2821 session->lu_reset_timeout = 15;
2822 session->abort_timeout = 10;
2823 session->scsi_cmds_max = scsi_cmds;
2824 session->cmds_max = total_cmds;
2825 session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2826 session->exp_cmdsn = initial_cmdsn + 1;
2827 session->max_cmdsn = initial_cmdsn + 1;
2828 session->max_r2t = 1;
2829 session->tt = iscsit;
2830 session->dd_data = cls_session->dd_data + sizeof(*session);
2831
2832 mutex_init(&session->eh_mutex);
2833 spin_lock_init(&session->frwd_lock);
2834 spin_lock_init(&session->back_lock);
2835
2836 /* initialize SCSI PDU commands pool */
2837 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2838 (void***)&session->cmds,
2839 cmd_task_size + sizeof(struct iscsi_task)))
2840 goto cmdpool_alloc_fail;
2841
2842 /* pre-format cmds pool with ITT */
2843 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2844 struct iscsi_task *task = session->cmds[cmd_i];
2845
2846 if (cmd_task_size)
2847 task->dd_data = &task[1];
2848 task->itt = cmd_i;
2849 task->state = ISCSI_TASK_FREE;
2850 INIT_LIST_HEAD(&task->running);
2851 }
2852
2853 if (!try_module_get(iscsit->owner))
2854 goto module_get_fail;
2855
2856 if (iscsi_add_session(cls_session, id))
2857 goto cls_session_fail;
2858
2859 return cls_session;
2860
2861cls_session_fail:
2862 module_put(iscsit->owner);
2863module_get_fail:
2864 iscsi_pool_free(&session->cmdpool);
2865cmdpool_alloc_fail:
2866 iscsi_free_session(cls_session);
2867dec_session_count:
2868 iscsi_host_dec_session_cnt(shost);
2869 return NULL;
2870}
2871EXPORT_SYMBOL_GPL(iscsi_session_setup);
2872
2873/**
2874 * iscsi_session_teardown - destroy session, host, and cls_session
2875 * @cls_session: iscsi session
2876 */
2877void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2878{
2879 struct iscsi_session *session = cls_session->dd_data;
2880 struct module *owner = cls_session->transport->owner;
2881 struct Scsi_Host *shost = session->host;
2882
2883 iscsi_pool_free(&session->cmdpool);
2884
2885 iscsi_remove_session(cls_session);
2886
2887 kfree(session->password);
2888 kfree(session->password_in);
2889 kfree(session->username);
2890 kfree(session->username_in);
2891 kfree(session->targetname);
2892 kfree(session->targetalias);
2893 kfree(session->initiatorname);
2894 kfree(session->boot_root);
2895 kfree(session->boot_nic);
2896 kfree(session->boot_target);
2897 kfree(session->ifacename);
2898 kfree(session->portal_type);
2899 kfree(session->discovery_parent_type);
2900
2901 iscsi_free_session(cls_session);
2902
2903 iscsi_host_dec_session_cnt(shost);
2904 module_put(owner);
2905}
2906EXPORT_SYMBOL_GPL(iscsi_session_teardown);
2907
2908/**
2909 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
2910 * @cls_session: iscsi_cls_session
2911 * @dd_size: private driver data size
2912 * @conn_idx: cid
2913 */
2914struct iscsi_cls_conn *
2915iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2916 uint32_t conn_idx)
2917{
2918 struct iscsi_session *session = cls_session->dd_data;
2919 struct iscsi_conn *conn;
2920 struct iscsi_cls_conn *cls_conn;
2921 char *data;
2922
2923 cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2924 conn_idx);
2925 if (!cls_conn)
2926 return NULL;
2927 conn = cls_conn->dd_data;
2928 memset(conn, 0, sizeof(*conn) + dd_size);
2929
2930 conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2931 conn->session = session;
2932 conn->cls_conn = cls_conn;
2933 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2934 conn->id = conn_idx;
2935 conn->exp_statsn = 0;
2936 conn->tmf_state = TMF_INITIAL;
2937
2938 timer_setup(&conn->transport_timer, iscsi_check_transport_timeouts, 0);
2939
2940 INIT_LIST_HEAD(&conn->mgmtqueue);
2941 INIT_LIST_HEAD(&conn->cmdqueue);
2942 INIT_LIST_HEAD(&conn->requeue);
2943 spin_lock_init(&conn->taskqueuelock);
2944 INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2945
2946 /* allocate login_task used for the login/text sequences */
2947 spin_lock_bh(&session->frwd_lock);
2948 if (!kfifo_out(&session->cmdpool.queue,
2949 (void*)&conn->login_task,
2950 sizeof(void*))) {
2951 spin_unlock_bh(&session->frwd_lock);
2952 goto login_task_alloc_fail;
2953 }
2954 spin_unlock_bh(&session->frwd_lock);
2955
2956 data = (char *) __get_free_pages(GFP_KERNEL,
2957 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2958 if (!data)
2959 goto login_task_data_alloc_fail;
2960 conn->login_task->data = conn->data = data;
2961
2962 timer_setup(&conn->tmf_timer, iscsi_tmf_timedout, 0);
2963 init_waitqueue_head(&conn->ehwait);
2964
2965 return cls_conn;
2966
2967login_task_data_alloc_fail:
2968 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2969 sizeof(void*));
2970login_task_alloc_fail:
2971 iscsi_destroy_conn(cls_conn);
2972 return NULL;
2973}
2974EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2975
2976/**
2977 * iscsi_conn_teardown - teardown iscsi connection
2978 * @cls_conn: iscsi class connection
2979 *
2980 * TODO: we may need to make this into a two step process
2981 * like scsi-mls remove + put host
2982 */
2983void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2984{
2985 struct iscsi_conn *conn = cls_conn->dd_data;
2986 struct iscsi_session *session = conn->session;
2987
2988 del_timer_sync(&conn->transport_timer);
2989
2990 mutex_lock(&session->eh_mutex);
2991 spin_lock_bh(&session->frwd_lock);
2992 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2993 if (session->leadconn == conn) {
2994 /*
2995 * leading connection? then give up on recovery.
2996 */
2997 session->state = ISCSI_STATE_TERMINATE;
2998 wake_up(&conn->ehwait);
2999 }
3000 spin_unlock_bh(&session->frwd_lock);
3001
3002 /* flush queued up work because we free the connection below */
3003 iscsi_suspend_tx(conn);
3004
3005 spin_lock_bh(&session->frwd_lock);
3006 free_pages((unsigned long) conn->data,
3007 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
3008 kfree(conn->persistent_address);
3009 kfree(conn->local_ipaddr);
3010 /* regular RX path uses back_lock */
3011 spin_lock_bh(&session->back_lock);
3012 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
3013 sizeof(void*));
3014 spin_unlock_bh(&session->back_lock);
3015 if (session->leadconn == conn)
3016 session->leadconn = NULL;
3017 spin_unlock_bh(&session->frwd_lock);
3018 mutex_unlock(&session->eh_mutex);
3019
3020 iscsi_destroy_conn(cls_conn);
3021}
3022EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
3023
3024int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
3025{
3026 struct iscsi_conn *conn = cls_conn->dd_data;
3027 struct iscsi_session *session = conn->session;
3028
3029 if (!session) {
3030 iscsi_conn_printk(KERN_ERR, conn,
3031 "can't start unbound connection\n");
3032 return -EPERM;
3033 }
3034
3035 if ((session->imm_data_en || !session->initial_r2t_en) &&
3036 session->first_burst > session->max_burst) {
3037 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
3038 "first_burst %d max_burst %d\n",
3039 session->first_burst, session->max_burst);
3040 return -EINVAL;
3041 }
3042
3043 if (conn->ping_timeout && !conn->recv_timeout) {
3044 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
3045 "zero. Using 5 seconds\n.");
3046 conn->recv_timeout = 5;
3047 }
3048
3049 if (conn->recv_timeout && !conn->ping_timeout) {
3050 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
3051 "zero. Using 5 seconds.\n");
3052 conn->ping_timeout = 5;
3053 }
3054
3055 spin_lock_bh(&session->frwd_lock);
3056 conn->c_stage = ISCSI_CONN_STARTED;
3057 session->state = ISCSI_STATE_LOGGED_IN;
3058 session->queued_cmdsn = session->cmdsn;
3059
3060 conn->last_recv = jiffies;
3061 conn->last_ping = jiffies;
3062 if (conn->recv_timeout && conn->ping_timeout)
3063 mod_timer(&conn->transport_timer,
3064 jiffies + (conn->recv_timeout * HZ));
3065
3066 switch(conn->stop_stage) {
3067 case STOP_CONN_RECOVER:
3068 /*
3069 * unblock eh_abort() if it is blocked. re-try all
3070 * commands after successful recovery
3071 */
3072 conn->stop_stage = 0;
3073 conn->tmf_state = TMF_INITIAL;
3074 session->age++;
3075 if (session->age == 16)
3076 session->age = 0;
3077 break;
3078 case STOP_CONN_TERM:
3079 conn->stop_stage = 0;
3080 break;
3081 default:
3082 break;
3083 }
3084 spin_unlock_bh(&session->frwd_lock);
3085
3086 iscsi_unblock_session(session->cls_session);
3087 wake_up(&conn->ehwait);
3088 return 0;
3089}
3090EXPORT_SYMBOL_GPL(iscsi_conn_start);
3091
3092static void
3093fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3094{
3095 struct iscsi_task *task;
3096 int i, state;
3097
3098 for (i = 0; i < conn->session->cmds_max; i++) {
3099 task = conn->session->cmds[i];
3100 if (task->sc)
3101 continue;
3102
3103 if (task->state == ISCSI_TASK_FREE)
3104 continue;
3105
3106 ISCSI_DBG_SESSION(conn->session,
3107 "failing mgmt itt 0x%x state %d\n",
3108 task->itt, task->state);
3109 state = ISCSI_TASK_ABRT_SESS_RECOV;
3110 if (task->state == ISCSI_TASK_PENDING)
3111 state = ISCSI_TASK_COMPLETED;
3112 iscsi_complete_task(task, state);
3113
3114 }
3115}
3116
3117static void iscsi_start_session_recovery(struct iscsi_session *session,
3118 struct iscsi_conn *conn, int flag)
3119{
3120 int old_stop_stage;
3121
3122 mutex_lock(&session->eh_mutex);
3123 spin_lock_bh(&session->frwd_lock);
3124 if (conn->stop_stage == STOP_CONN_TERM) {
3125 spin_unlock_bh(&session->frwd_lock);
3126 mutex_unlock(&session->eh_mutex);
3127 return;
3128 }
3129
3130 /*
3131 * When this is called for the in_login state, we only want to clean
3132 * up the login task and connection. We do not need to block and set
3133 * the recovery state again
3134 */
3135 if (flag == STOP_CONN_TERM)
3136 session->state = ISCSI_STATE_TERMINATE;
3137 else if (conn->stop_stage != STOP_CONN_RECOVER)
3138 session->state = ISCSI_STATE_IN_RECOVERY;
3139
3140 old_stop_stage = conn->stop_stage;
3141 conn->stop_stage = flag;
3142 spin_unlock_bh(&session->frwd_lock);
3143
3144 del_timer_sync(&conn->transport_timer);
3145 iscsi_suspend_tx(conn);
3146
3147 spin_lock_bh(&session->frwd_lock);
3148 conn->c_stage = ISCSI_CONN_STOPPED;
3149 spin_unlock_bh(&session->frwd_lock);
3150
3151 /*
3152 * for connection level recovery we should not calculate
3153 * header digest. conn->hdr_size used for optimization
3154 * in hdr_extract() and will be re-negotiated at
3155 * set_param() time.
3156 */
3157 if (flag == STOP_CONN_RECOVER) {
3158 conn->hdrdgst_en = 0;
3159 conn->datadgst_en = 0;
3160 if (session->state == ISCSI_STATE_IN_RECOVERY &&
3161 old_stop_stage != STOP_CONN_RECOVER) {
3162 ISCSI_DBG_SESSION(session, "blocking session\n");
3163 iscsi_block_session(session->cls_session);
3164 }
3165 }
3166
3167 /*
3168 * flush queues.
3169 */
3170 spin_lock_bh(&session->frwd_lock);
3171 fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3172 fail_mgmt_tasks(session, conn);
3173 memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
3174 spin_unlock_bh(&session->frwd_lock);
3175 mutex_unlock(&session->eh_mutex);
3176}
3177
3178void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3179{
3180 struct iscsi_conn *conn = cls_conn->dd_data;
3181 struct iscsi_session *session = conn->session;
3182
3183 switch (flag) {
3184 case STOP_CONN_RECOVER:
3185 case STOP_CONN_TERM:
3186 iscsi_start_session_recovery(session, conn, flag);
3187 break;
3188 default:
3189 iscsi_conn_printk(KERN_ERR, conn,
3190 "invalid stop flag %d\n", flag);
3191 }
3192}
3193EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3194
3195int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3196 struct iscsi_cls_conn *cls_conn, int is_leading)
3197{
3198 struct iscsi_session *session = cls_session->dd_data;
3199 struct iscsi_conn *conn = cls_conn->dd_data;
3200
3201 spin_lock_bh(&session->frwd_lock);
3202 if (is_leading)
3203 session->leadconn = conn;
3204 spin_unlock_bh(&session->frwd_lock);
3205
3206 /*
3207 * Unblock xmitworker(), Login Phase will pass through.
3208 */
3209 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3210 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3211 return 0;
3212}
3213EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3214
3215int iscsi_switch_str_param(char **param, char *new_val_buf)
3216{
3217 char *new_val;
3218
3219 if (*param) {
3220 if (!strcmp(*param, new_val_buf))
3221 return 0;
3222 }
3223
3224 new_val = kstrdup(new_val_buf, GFP_NOIO);
3225 if (!new_val)
3226 return -ENOMEM;
3227
3228 kfree(*param);
3229 *param = new_val;
3230 return 0;
3231}
3232EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3233
3234int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3235 enum iscsi_param param, char *buf, int buflen)
3236{
3237 struct iscsi_conn *conn = cls_conn->dd_data;
3238 struct iscsi_session *session = conn->session;
3239 int val;
3240
3241 switch(param) {
3242 case ISCSI_PARAM_FAST_ABORT:
3243 sscanf(buf, "%d", &session->fast_abort);
3244 break;
3245 case ISCSI_PARAM_ABORT_TMO:
3246 sscanf(buf, "%d", &session->abort_timeout);
3247 break;
3248 case ISCSI_PARAM_LU_RESET_TMO:
3249 sscanf(buf, "%d", &session->lu_reset_timeout);
3250 break;
3251 case ISCSI_PARAM_TGT_RESET_TMO:
3252 sscanf(buf, "%d", &session->tgt_reset_timeout);
3253 break;
3254 case ISCSI_PARAM_PING_TMO:
3255 sscanf(buf, "%d", &conn->ping_timeout);
3256 break;
3257 case ISCSI_PARAM_RECV_TMO:
3258 sscanf(buf, "%d", &conn->recv_timeout);
3259 break;
3260 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3261 sscanf(buf, "%d", &conn->max_recv_dlength);
3262 break;
3263 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3264 sscanf(buf, "%d", &conn->max_xmit_dlength);
3265 break;
3266 case ISCSI_PARAM_HDRDGST_EN:
3267 sscanf(buf, "%d", &conn->hdrdgst_en);
3268 break;
3269 case ISCSI_PARAM_DATADGST_EN:
3270 sscanf(buf, "%d", &conn->datadgst_en);
3271 break;
3272 case ISCSI_PARAM_INITIAL_R2T_EN:
3273 sscanf(buf, "%d", &session->initial_r2t_en);
3274 break;
3275 case ISCSI_PARAM_MAX_R2T:
3276 sscanf(buf, "%hu", &session->max_r2t);
3277 break;
3278 case ISCSI_PARAM_IMM_DATA_EN:
3279 sscanf(buf, "%d", &session->imm_data_en);
3280 break;
3281 case ISCSI_PARAM_FIRST_BURST:
3282 sscanf(buf, "%d", &session->first_burst);
3283 break;
3284 case ISCSI_PARAM_MAX_BURST:
3285 sscanf(buf, "%d", &session->max_burst);
3286 break;
3287 case ISCSI_PARAM_PDU_INORDER_EN:
3288 sscanf(buf, "%d", &session->pdu_inorder_en);
3289 break;
3290 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3291 sscanf(buf, "%d", &session->dataseq_inorder_en);
3292 break;
3293 case ISCSI_PARAM_ERL:
3294 sscanf(buf, "%d", &session->erl);
3295 break;
3296 case ISCSI_PARAM_EXP_STATSN:
3297 sscanf(buf, "%u", &conn->exp_statsn);
3298 break;
3299 case ISCSI_PARAM_USERNAME:
3300 return iscsi_switch_str_param(&session->username, buf);
3301 case ISCSI_PARAM_USERNAME_IN:
3302 return iscsi_switch_str_param(&session->username_in, buf);
3303 case ISCSI_PARAM_PASSWORD:
3304 return iscsi_switch_str_param(&session->password, buf);
3305 case ISCSI_PARAM_PASSWORD_IN:
3306 return iscsi_switch_str_param(&session->password_in, buf);
3307 case ISCSI_PARAM_TARGET_NAME:
3308 return iscsi_switch_str_param(&session->targetname, buf);
3309 case ISCSI_PARAM_TARGET_ALIAS:
3310 return iscsi_switch_str_param(&session->targetalias, buf);
3311 case ISCSI_PARAM_TPGT:
3312 sscanf(buf, "%d", &session->tpgt);
3313 break;
3314 case ISCSI_PARAM_PERSISTENT_PORT:
3315 sscanf(buf, "%d", &conn->persistent_port);
3316 break;
3317 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3318 return iscsi_switch_str_param(&conn->persistent_address, buf);
3319 case ISCSI_PARAM_IFACE_NAME:
3320 return iscsi_switch_str_param(&session->ifacename, buf);
3321 case ISCSI_PARAM_INITIATOR_NAME:
3322 return iscsi_switch_str_param(&session->initiatorname, buf);
3323 case ISCSI_PARAM_BOOT_ROOT:
3324 return iscsi_switch_str_param(&session->boot_root, buf);
3325 case ISCSI_PARAM_BOOT_NIC:
3326 return iscsi_switch_str_param(&session->boot_nic, buf);
3327 case ISCSI_PARAM_BOOT_TARGET:
3328 return iscsi_switch_str_param(&session->boot_target, buf);
3329 case ISCSI_PARAM_PORTAL_TYPE:
3330 return iscsi_switch_str_param(&session->portal_type, buf);
3331 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3332 return iscsi_switch_str_param(&session->discovery_parent_type,
3333 buf);
3334 case ISCSI_PARAM_DISCOVERY_SESS:
3335 sscanf(buf, "%d", &val);
3336 session->discovery_sess = !!val;
3337 break;
3338 case ISCSI_PARAM_LOCAL_IPADDR:
3339 return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3340 default:
3341 return -ENOSYS;
3342 }
3343
3344 return 0;
3345}
3346EXPORT_SYMBOL_GPL(iscsi_set_param);
3347
3348int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3349 enum iscsi_param param, char *buf)
3350{
3351 struct iscsi_session *session = cls_session->dd_data;
3352 int len;
3353
3354 switch(param) {
3355 case ISCSI_PARAM_FAST_ABORT:
3356 len = sprintf(buf, "%d\n", session->fast_abort);
3357 break;
3358 case ISCSI_PARAM_ABORT_TMO:
3359 len = sprintf(buf, "%d\n", session->abort_timeout);
3360 break;
3361 case ISCSI_PARAM_LU_RESET_TMO:
3362 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
3363 break;
3364 case ISCSI_PARAM_TGT_RESET_TMO:
3365 len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
3366 break;
3367 case ISCSI_PARAM_INITIAL_R2T_EN:
3368 len = sprintf(buf, "%d\n", session->initial_r2t_en);
3369 break;
3370 case ISCSI_PARAM_MAX_R2T:
3371 len = sprintf(buf, "%hu\n", session->max_r2t);
3372 break;
3373 case ISCSI_PARAM_IMM_DATA_EN:
3374 len = sprintf(buf, "%d\n", session->imm_data_en);
3375 break;
3376 case ISCSI_PARAM_FIRST_BURST:
3377 len = sprintf(buf, "%u\n", session->first_burst);
3378 break;
3379 case ISCSI_PARAM_MAX_BURST:
3380 len = sprintf(buf, "%u\n", session->max_burst);
3381 break;
3382 case ISCSI_PARAM_PDU_INORDER_EN:
3383 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
3384 break;
3385 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3386 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
3387 break;
3388 case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3389 len = sprintf(buf, "%d\n", session->def_taskmgmt_tmo);
3390 break;
3391 case ISCSI_PARAM_ERL:
3392 len = sprintf(buf, "%d\n", session->erl);
3393 break;
3394 case ISCSI_PARAM_TARGET_NAME:
3395 len = sprintf(buf, "%s\n", session->targetname);
3396 break;
3397 case ISCSI_PARAM_TARGET_ALIAS:
3398 len = sprintf(buf, "%s\n", session->targetalias);
3399 break;
3400 case ISCSI_PARAM_TPGT:
3401 len = sprintf(buf, "%d\n", session->tpgt);
3402 break;
3403 case ISCSI_PARAM_USERNAME:
3404 len = sprintf(buf, "%s\n", session->username);
3405 break;
3406 case ISCSI_PARAM_USERNAME_IN:
3407 len = sprintf(buf, "%s\n", session->username_in);
3408 break;
3409 case ISCSI_PARAM_PASSWORD:
3410 len = sprintf(buf, "%s\n", session->password);
3411 break;
3412 case ISCSI_PARAM_PASSWORD_IN:
3413 len = sprintf(buf, "%s\n", session->password_in);
3414 break;
3415 case ISCSI_PARAM_IFACE_NAME:
3416 len = sprintf(buf, "%s\n", session->ifacename);
3417 break;
3418 case ISCSI_PARAM_INITIATOR_NAME:
3419 len = sprintf(buf, "%s\n", session->initiatorname);
3420 break;
3421 case ISCSI_PARAM_BOOT_ROOT:
3422 len = sprintf(buf, "%s\n", session->boot_root);
3423 break;
3424 case ISCSI_PARAM_BOOT_NIC:
3425 len = sprintf(buf, "%s\n", session->boot_nic);
3426 break;
3427 case ISCSI_PARAM_BOOT_TARGET:
3428 len = sprintf(buf, "%s\n", session->boot_target);
3429 break;
3430 case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3431 len = sprintf(buf, "%u\n", session->auto_snd_tgt_disable);
3432 break;
3433 case ISCSI_PARAM_DISCOVERY_SESS:
3434 len = sprintf(buf, "%u\n", session->discovery_sess);
3435 break;
3436 case ISCSI_PARAM_PORTAL_TYPE:
3437 len = sprintf(buf, "%s\n", session->portal_type);
3438 break;
3439 case ISCSI_PARAM_CHAP_AUTH_EN:
3440 len = sprintf(buf, "%u\n", session->chap_auth_en);
3441 break;
3442 case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3443 len = sprintf(buf, "%u\n", session->discovery_logout_en);
3444 break;
3445 case ISCSI_PARAM_BIDI_CHAP_EN:
3446 len = sprintf(buf, "%u\n", session->bidi_chap_en);
3447 break;
3448 case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3449 len = sprintf(buf, "%u\n", session->discovery_auth_optional);
3450 break;
3451 case ISCSI_PARAM_DEF_TIME2WAIT:
3452 len = sprintf(buf, "%d\n", session->time2wait);
3453 break;
3454 case ISCSI_PARAM_DEF_TIME2RETAIN:
3455 len = sprintf(buf, "%d\n", session->time2retain);
3456 break;
3457 case ISCSI_PARAM_TSID:
3458 len = sprintf(buf, "%u\n", session->tsid);
3459 break;
3460 case ISCSI_PARAM_ISID:
3461 len = sprintf(buf, "%02x%02x%02x%02x%02x%02x\n",
3462 session->isid[0], session->isid[1],
3463 session->isid[2], session->isid[3],
3464 session->isid[4], session->isid[5]);
3465 break;
3466 case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3467 len = sprintf(buf, "%u\n", session->discovery_parent_idx);
3468 break;
3469 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3470 if (session->discovery_parent_type)
3471 len = sprintf(buf, "%s\n",
3472 session->discovery_parent_type);
3473 else
3474 len = sprintf(buf, "\n");
3475 break;
3476 default:
3477 return -ENOSYS;
3478 }
3479
3480 return len;
3481}
3482EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3483
3484int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3485 enum iscsi_param param, char *buf)
3486{
3487 struct sockaddr_in6 *sin6 = NULL;
3488 struct sockaddr_in *sin = NULL;
3489 int len;
3490
3491 switch (addr->ss_family) {
3492 case AF_INET:
3493 sin = (struct sockaddr_in *)addr;
3494 break;
3495 case AF_INET6:
3496 sin6 = (struct sockaddr_in6 *)addr;
3497 break;
3498 default:
3499 return -EINVAL;
3500 }
3501
3502 switch (param) {
3503 case ISCSI_PARAM_CONN_ADDRESS:
3504 case ISCSI_HOST_PARAM_IPADDRESS:
3505 if (sin)
3506 len = sprintf(buf, "%pI4\n", &sin->sin_addr.s_addr);
3507 else
3508 len = sprintf(buf, "%pI6\n", &sin6->sin6_addr);
3509 break;
3510 case ISCSI_PARAM_CONN_PORT:
3511 case ISCSI_PARAM_LOCAL_PORT:
3512 if (sin)
3513 len = sprintf(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3514 else
3515 len = sprintf(buf, "%hu\n",
3516 be16_to_cpu(sin6->sin6_port));
3517 break;
3518 default:
3519 return -EINVAL;
3520 }
3521
3522 return len;
3523}
3524EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3525
3526int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3527 enum iscsi_param param, char *buf)
3528{
3529 struct iscsi_conn *conn = cls_conn->dd_data;
3530 int len;
3531
3532 switch(param) {
3533 case ISCSI_PARAM_PING_TMO:
3534 len = sprintf(buf, "%u\n", conn->ping_timeout);
3535 break;
3536 case ISCSI_PARAM_RECV_TMO:
3537 len = sprintf(buf, "%u\n", conn->recv_timeout);
3538 break;
3539 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3540 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
3541 break;
3542 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3543 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
3544 break;
3545 case ISCSI_PARAM_HDRDGST_EN:
3546 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
3547 break;
3548 case ISCSI_PARAM_DATADGST_EN:
3549 len = sprintf(buf, "%d\n", conn->datadgst_en);
3550 break;
3551 case ISCSI_PARAM_IFMARKER_EN:
3552 len = sprintf(buf, "%d\n", conn->ifmarker_en);
3553 break;
3554 case ISCSI_PARAM_OFMARKER_EN:
3555 len = sprintf(buf, "%d\n", conn->ofmarker_en);
3556 break;
3557 case ISCSI_PARAM_EXP_STATSN:
3558 len = sprintf(buf, "%u\n", conn->exp_statsn);
3559 break;
3560 case ISCSI_PARAM_PERSISTENT_PORT:
3561 len = sprintf(buf, "%d\n", conn->persistent_port);
3562 break;
3563 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3564 len = sprintf(buf, "%s\n", conn->persistent_address);
3565 break;
3566 case ISCSI_PARAM_STATSN:
3567 len = sprintf(buf, "%u\n", conn->statsn);
3568 break;
3569 case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3570 len = sprintf(buf, "%u\n", conn->max_segment_size);
3571 break;
3572 case ISCSI_PARAM_KEEPALIVE_TMO:
3573 len = sprintf(buf, "%u\n", conn->keepalive_tmo);
3574 break;
3575 case ISCSI_PARAM_LOCAL_PORT:
3576 len = sprintf(buf, "%u\n", conn->local_port);
3577 break;
3578 case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3579 len = sprintf(buf, "%u\n", conn->tcp_timestamp_stat);
3580 break;
3581 case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3582 len = sprintf(buf, "%u\n", conn->tcp_nagle_disable);
3583 break;
3584 case ISCSI_PARAM_TCP_WSF_DISABLE:
3585 len = sprintf(buf, "%u\n", conn->tcp_wsf_disable);
3586 break;
3587 case ISCSI_PARAM_TCP_TIMER_SCALE:
3588 len = sprintf(buf, "%u\n", conn->tcp_timer_scale);
3589 break;
3590 case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3591 len = sprintf(buf, "%u\n", conn->tcp_timestamp_en);
3592 break;
3593 case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3594 len = sprintf(buf, "%u\n", conn->fragment_disable);
3595 break;
3596 case ISCSI_PARAM_IPV4_TOS:
3597 len = sprintf(buf, "%u\n", conn->ipv4_tos);
3598 break;
3599 case ISCSI_PARAM_IPV6_TC:
3600 len = sprintf(buf, "%u\n", conn->ipv6_traffic_class);
3601 break;
3602 case ISCSI_PARAM_IPV6_FLOW_LABEL:
3603 len = sprintf(buf, "%u\n", conn->ipv6_flow_label);
3604 break;
3605 case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3606 len = sprintf(buf, "%u\n", conn->is_fw_assigned_ipv6);
3607 break;
3608 case ISCSI_PARAM_TCP_XMIT_WSF:
3609 len = sprintf(buf, "%u\n", conn->tcp_xmit_wsf);
3610 break;
3611 case ISCSI_PARAM_TCP_RECV_WSF:
3612 len = sprintf(buf, "%u\n", conn->tcp_recv_wsf);
3613 break;
3614 case ISCSI_PARAM_LOCAL_IPADDR:
3615 len = sprintf(buf, "%s\n", conn->local_ipaddr);
3616 break;
3617 default:
3618 return -ENOSYS;
3619 }
3620
3621 return len;
3622}
3623EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3624
3625int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3626 char *buf)
3627{
3628 struct iscsi_host *ihost = shost_priv(shost);
3629 int len;
3630
3631 switch (param) {
3632 case ISCSI_HOST_PARAM_NETDEV_NAME:
3633 len = sprintf(buf, "%s\n", ihost->netdev);
3634 break;
3635 case ISCSI_HOST_PARAM_HWADDRESS:
3636 len = sprintf(buf, "%s\n", ihost->hwaddress);
3637 break;
3638 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3639 len = sprintf(buf, "%s\n", ihost->initiatorname);
3640 break;
3641 default:
3642 return -ENOSYS;
3643 }
3644
3645 return len;
3646}
3647EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3648
3649int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3650 char *buf, int buflen)
3651{
3652 struct iscsi_host *ihost = shost_priv(shost);
3653
3654 switch (param) {
3655 case ISCSI_HOST_PARAM_NETDEV_NAME:
3656 return iscsi_switch_str_param(&ihost->netdev, buf);
3657 case ISCSI_HOST_PARAM_HWADDRESS:
3658 return iscsi_switch_str_param(&ihost->hwaddress, buf);
3659 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3660 return iscsi_switch_str_param(&ihost->initiatorname, buf);
3661 default:
3662 return -ENOSYS;
3663 }
3664
3665 return 0;
3666}
3667EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3668
3669MODULE_AUTHOR("Mike Christie");
3670MODULE_DESCRIPTION("iSCSI library functions");
3671MODULE_LICENSE("GPL");
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/kfifo.h>
26#include <linux/delay.h>
27#include <linux/log2.h>
28#include <linux/slab.h>
29#include <linux/module.h>
30#include <asm/unaligned.h>
31#include <net/tcp.h>
32#include <scsi/scsi_cmnd.h>
33#include <scsi/scsi_device.h>
34#include <scsi/scsi_eh.h>
35#include <scsi/scsi_tcq.h>
36#include <scsi/scsi_host.h>
37#include <scsi/scsi.h>
38#include <scsi/iscsi_proto.h>
39#include <scsi/scsi_transport.h>
40#include <scsi/scsi_transport_iscsi.h>
41#include <scsi/libiscsi.h>
42
43static int iscsi_dbg_lib_conn;
44module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
45 S_IRUGO | S_IWUSR);
46MODULE_PARM_DESC(debug_libiscsi_conn,
47 "Turn on debugging for connections in libiscsi module. "
48 "Set to 1 to turn on, and zero to turn off. Default is off.");
49
50static int iscsi_dbg_lib_session;
51module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
52 S_IRUGO | S_IWUSR);
53MODULE_PARM_DESC(debug_libiscsi_session,
54 "Turn on debugging for sessions in libiscsi module. "
55 "Set to 1 to turn on, and zero to turn off. Default is off.");
56
57static int iscsi_dbg_lib_eh;
58module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
59 S_IRUGO | S_IWUSR);
60MODULE_PARM_DESC(debug_libiscsi_eh,
61 "Turn on debugging for error handling in libiscsi module. "
62 "Set to 1 to turn on, and zero to turn off. Default is off.");
63
64#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...) \
65 do { \
66 if (iscsi_dbg_lib_conn) \
67 iscsi_conn_printk(KERN_INFO, _conn, \
68 "%s " dbg_fmt, \
69 __func__, ##arg); \
70 } while (0);
71
72#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...) \
73 do { \
74 if (iscsi_dbg_lib_session) \
75 iscsi_session_printk(KERN_INFO, _session, \
76 "%s " dbg_fmt, \
77 __func__, ##arg); \
78 } while (0);
79
80#define ISCSI_DBG_EH(_session, dbg_fmt, arg...) \
81 do { \
82 if (iscsi_dbg_lib_eh) \
83 iscsi_session_printk(KERN_INFO, _session, \
84 "%s " dbg_fmt, \
85 __func__, ##arg); \
86 } while (0);
87
88inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
89{
90 struct Scsi_Host *shost = conn->session->host;
91 struct iscsi_host *ihost = shost_priv(shost);
92
93 if (ihost->workq)
94 queue_work(ihost->workq, &conn->xmitwork);
95}
96EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
97
98static void __iscsi_update_cmdsn(struct iscsi_session *session,
99 uint32_t exp_cmdsn, uint32_t max_cmdsn)
100{
101 /*
102 * standard specifies this check for when to update expected and
103 * max sequence numbers
104 */
105 if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
106 return;
107
108 if (exp_cmdsn != session->exp_cmdsn &&
109 !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
110 session->exp_cmdsn = exp_cmdsn;
111
112 if (max_cmdsn != session->max_cmdsn &&
113 !iscsi_sna_lt(max_cmdsn, session->max_cmdsn))
114 session->max_cmdsn = max_cmdsn;
115}
116
117void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
118{
119 __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
120 be32_to_cpu(hdr->max_cmdsn));
121}
122EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
123
124/**
125 * iscsi_prep_data_out_pdu - initialize Data-Out
126 * @task: scsi command task
127 * @r2t: R2T info
128 * @hdr: iscsi data in pdu
129 *
130 * Notes:
131 * Initialize Data-Out within this R2T sequence and finds
132 * proper data_offset within this SCSI command.
133 *
134 * This function is called with connection lock taken.
135 **/
136void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
137 struct iscsi_data *hdr)
138{
139 struct iscsi_conn *conn = task->conn;
140 unsigned int left = r2t->data_length - r2t->sent;
141
142 task->hdr_len = sizeof(struct iscsi_data);
143
144 memset(hdr, 0, sizeof(struct iscsi_data));
145 hdr->ttt = r2t->ttt;
146 hdr->datasn = cpu_to_be32(r2t->datasn);
147 r2t->datasn++;
148 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
149 hdr->lun = task->lun;
150 hdr->itt = task->hdr_itt;
151 hdr->exp_statsn = r2t->exp_statsn;
152 hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
153 if (left > conn->max_xmit_dlength) {
154 hton24(hdr->dlength, conn->max_xmit_dlength);
155 r2t->data_count = conn->max_xmit_dlength;
156 hdr->flags = 0;
157 } else {
158 hton24(hdr->dlength, left);
159 r2t->data_count = left;
160 hdr->flags = ISCSI_FLAG_CMD_FINAL;
161 }
162 conn->dataout_pdus_cnt++;
163}
164EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
165
166static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
167{
168 unsigned exp_len = task->hdr_len + len;
169
170 if (exp_len > task->hdr_max) {
171 WARN_ON(1);
172 return -EINVAL;
173 }
174
175 WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
176 task->hdr_len = exp_len;
177 return 0;
178}
179
180/*
181 * make an extended cdb AHS
182 */
183static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
184{
185 struct scsi_cmnd *cmd = task->sc;
186 unsigned rlen, pad_len;
187 unsigned short ahslength;
188 struct iscsi_ecdb_ahdr *ecdb_ahdr;
189 int rc;
190
191 ecdb_ahdr = iscsi_next_hdr(task);
192 rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
193
194 BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
195 ahslength = rlen + sizeof(ecdb_ahdr->reserved);
196
197 pad_len = iscsi_padding(rlen);
198
199 rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
200 sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
201 if (rc)
202 return rc;
203
204 if (pad_len)
205 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
206
207 ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
208 ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
209 ecdb_ahdr->reserved = 0;
210 memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
211
212 ISCSI_DBG_SESSION(task->conn->session,
213 "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
214 "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
215 "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
216 task->hdr_len);
217 return 0;
218}
219
220static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
221{
222 struct scsi_cmnd *sc = task->sc;
223 struct iscsi_rlength_ahdr *rlen_ahdr;
224 int rc;
225
226 rlen_ahdr = iscsi_next_hdr(task);
227 rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
228 if (rc)
229 return rc;
230
231 rlen_ahdr->ahslength =
232 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
233 sizeof(rlen_ahdr->reserved));
234 rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
235 rlen_ahdr->reserved = 0;
236 rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
237
238 ISCSI_DBG_SESSION(task->conn->session,
239 "bidi-in rlen_ahdr->read_length(%d) "
240 "rlen_ahdr->ahslength(%d)\n",
241 be32_to_cpu(rlen_ahdr->read_length),
242 be16_to_cpu(rlen_ahdr->ahslength));
243 return 0;
244}
245
246/**
247 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
248 * @task: iscsi task
249 * @opcode: opcode to check for
250 *
251 * During TMF a task has to be checked if it's affected.
252 * All unrelated I/O can be passed through, but I/O to the
253 * affected LUN should be restricted.
254 * If 'fast_abort' is set we won't be sending any I/O to the
255 * affected LUN.
256 * Otherwise the target is waiting for all TTTs to be completed,
257 * so we have to send all outstanding Data-Out PDUs to the target.
258 */
259static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
260{
261 struct iscsi_conn *conn = task->conn;
262 struct iscsi_tm *tmf = &conn->tmhdr;
263 u64 hdr_lun;
264
265 if (conn->tmf_state == TMF_INITIAL)
266 return 0;
267
268 if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
269 return 0;
270
271 switch (ISCSI_TM_FUNC_VALUE(tmf)) {
272 case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
273 /*
274 * Allow PDUs for unrelated LUNs
275 */
276 hdr_lun = scsilun_to_int(&tmf->lun);
277 if (hdr_lun != task->sc->device->lun)
278 return 0;
279 /* fall through */
280 case ISCSI_TM_FUNC_TARGET_WARM_RESET:
281 /*
282 * Fail all SCSI cmd PDUs
283 */
284 if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
285 iscsi_conn_printk(KERN_INFO, conn,
286 "task [op %x/%x itt "
287 "0x%x/0x%x] "
288 "rejected.\n",
289 task->hdr->opcode, opcode,
290 task->itt, task->hdr_itt);
291 return -EACCES;
292 }
293 /*
294 * And also all data-out PDUs in response to R2T
295 * if fast_abort is set.
296 */
297 if (conn->session->fast_abort) {
298 iscsi_conn_printk(KERN_INFO, conn,
299 "task [op %x/%x itt "
300 "0x%x/0x%x] fast abort.\n",
301 task->hdr->opcode, opcode,
302 task->itt, task->hdr_itt);
303 return -EACCES;
304 }
305 break;
306 case ISCSI_TM_FUNC_ABORT_TASK:
307 /*
308 * the caller has already checked if the task
309 * they want to abort was in the pending queue so if
310 * we are here the cmd pdu has gone out already, and
311 * we will only hit this for data-outs
312 */
313 if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
314 task->hdr_itt == tmf->rtt) {
315 ISCSI_DBG_SESSION(conn->session,
316 "Preventing task %x/%x from sending "
317 "data-out due to abort task in "
318 "progress\n", task->itt,
319 task->hdr_itt);
320 return -EACCES;
321 }
322 break;
323 }
324
325 return 0;
326}
327
328/**
329 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
330 * @task: iscsi task
331 *
332 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
333 * fields like dlength or final based on how much data it sends
334 */
335static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
336{
337 struct iscsi_conn *conn = task->conn;
338 struct iscsi_session *session = conn->session;
339 struct scsi_cmnd *sc = task->sc;
340 struct iscsi_scsi_req *hdr;
341 unsigned hdrlength, cmd_len, transfer_length;
342 itt_t itt;
343 int rc;
344
345 rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
346 if (rc)
347 return rc;
348
349 if (conn->session->tt->alloc_pdu) {
350 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
351 if (rc)
352 return rc;
353 }
354 hdr = (struct iscsi_scsi_req *)task->hdr;
355 itt = hdr->itt;
356 memset(hdr, 0, sizeof(*hdr));
357
358 if (session->tt->parse_pdu_itt)
359 hdr->itt = task->hdr_itt = itt;
360 else
361 hdr->itt = task->hdr_itt = build_itt(task->itt,
362 task->conn->session->age);
363 task->hdr_len = 0;
364 rc = iscsi_add_hdr(task, sizeof(*hdr));
365 if (rc)
366 return rc;
367 hdr->opcode = ISCSI_OP_SCSI_CMD;
368 hdr->flags = ISCSI_ATTR_SIMPLE;
369 int_to_scsilun(sc->device->lun, &hdr->lun);
370 task->lun = hdr->lun;
371 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
372 cmd_len = sc->cmd_len;
373 if (cmd_len < ISCSI_CDB_SIZE)
374 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
375 else if (cmd_len > ISCSI_CDB_SIZE) {
376 rc = iscsi_prep_ecdb_ahs(task);
377 if (rc)
378 return rc;
379 cmd_len = ISCSI_CDB_SIZE;
380 }
381 memcpy(hdr->cdb, sc->cmnd, cmd_len);
382
383 task->imm_count = 0;
384 if (scsi_bidi_cmnd(sc)) {
385 hdr->flags |= ISCSI_FLAG_CMD_READ;
386 rc = iscsi_prep_bidi_ahs(task);
387 if (rc)
388 return rc;
389 }
390
391 if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL)
392 task->protected = true;
393
394 transfer_length = scsi_transfer_length(sc);
395 hdr->data_length = cpu_to_be32(transfer_length);
396 if (sc->sc_data_direction == DMA_TO_DEVICE) {
397 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
398
399 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
400 /*
401 * Write counters:
402 *
403 * imm_count bytes to be sent right after
404 * SCSI PDU Header
405 *
406 * unsol_count bytes(as Data-Out) to be sent
407 * without R2T ack right after
408 * immediate data
409 *
410 * r2t data_length bytes to be sent via R2T ack's
411 *
412 * pad_count bytes to be sent as zero-padding
413 */
414 memset(r2t, 0, sizeof(*r2t));
415
416 if (session->imm_data_en) {
417 if (transfer_length >= session->first_burst)
418 task->imm_count = min(session->first_burst,
419 conn->max_xmit_dlength);
420 else
421 task->imm_count = min(transfer_length,
422 conn->max_xmit_dlength);
423 hton24(hdr->dlength, task->imm_count);
424 } else
425 zero_data(hdr->dlength);
426
427 if (!session->initial_r2t_en) {
428 r2t->data_length = min(session->first_burst,
429 transfer_length) -
430 task->imm_count;
431 r2t->data_offset = task->imm_count;
432 r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
433 r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
434 }
435
436 if (!task->unsol_r2t.data_length)
437 /* No unsolicit Data-Out's */
438 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
439 } else {
440 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
441 zero_data(hdr->dlength);
442
443 if (sc->sc_data_direction == DMA_FROM_DEVICE)
444 hdr->flags |= ISCSI_FLAG_CMD_READ;
445 }
446
447 /* calculate size of additional header segments (AHSs) */
448 hdrlength = task->hdr_len - sizeof(*hdr);
449
450 WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
451 hdrlength /= ISCSI_PAD_LEN;
452
453 WARN_ON(hdrlength >= 256);
454 hdr->hlength = hdrlength & 0xFF;
455 hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
456
457 if (session->tt->init_task && session->tt->init_task(task))
458 return -EIO;
459
460 task->state = ISCSI_TASK_RUNNING;
461 session->cmdsn++;
462
463 conn->scsicmd_pdus_cnt++;
464 ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
465 "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
466 scsi_bidi_cmnd(sc) ? "bidirectional" :
467 sc->sc_data_direction == DMA_TO_DEVICE ?
468 "write" : "read", conn->id, sc, sc->cmnd[0],
469 task->itt, transfer_length,
470 scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
471 session->cmdsn,
472 session->max_cmdsn - session->exp_cmdsn + 1);
473 return 0;
474}
475
476/**
477 * iscsi_free_task - free a task
478 * @task: iscsi cmd task
479 *
480 * Must be called with session back_lock.
481 * This function returns the scsi command to scsi-ml or cleans
482 * up mgmt tasks then returns the task to the pool.
483 */
484static void iscsi_free_task(struct iscsi_task *task)
485{
486 struct iscsi_conn *conn = task->conn;
487 struct iscsi_session *session = conn->session;
488 struct scsi_cmnd *sc = task->sc;
489 int oldstate = task->state;
490
491 ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
492 task->itt, task->state, task->sc);
493
494 session->tt->cleanup_task(task);
495 task->state = ISCSI_TASK_FREE;
496 task->sc = NULL;
497 /*
498 * login task is preallocated so do not free
499 */
500 if (conn->login_task == task)
501 return;
502
503 kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
504
505 if (sc) {
506 /* SCSI eh reuses commands to verify us */
507 sc->SCp.ptr = NULL;
508 /*
509 * queue command may call this to free the task, so
510 * it will decide how to return sc to scsi-ml.
511 */
512 if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
513 sc->scsi_done(sc);
514 }
515}
516
517void __iscsi_get_task(struct iscsi_task *task)
518{
519 atomic_inc(&task->refcount);
520}
521EXPORT_SYMBOL_GPL(__iscsi_get_task);
522
523void __iscsi_put_task(struct iscsi_task *task)
524{
525 if (atomic_dec_and_test(&task->refcount))
526 iscsi_free_task(task);
527}
528EXPORT_SYMBOL_GPL(__iscsi_put_task);
529
530void iscsi_put_task(struct iscsi_task *task)
531{
532 struct iscsi_session *session = task->conn->session;
533
534 /* regular RX path uses back_lock */
535 spin_lock_bh(&session->back_lock);
536 __iscsi_put_task(task);
537 spin_unlock_bh(&session->back_lock);
538}
539EXPORT_SYMBOL_GPL(iscsi_put_task);
540
541/**
542 * iscsi_complete_task - finish a task
543 * @task: iscsi cmd task
544 * @state: state to complete task with
545 *
546 * Must be called with session back_lock.
547 */
548static void iscsi_complete_task(struct iscsi_task *task, int state)
549{
550 struct iscsi_conn *conn = task->conn;
551
552 ISCSI_DBG_SESSION(conn->session,
553 "complete task itt 0x%x state %d sc %p\n",
554 task->itt, task->state, task->sc);
555 if (task->state == ISCSI_TASK_COMPLETED ||
556 task->state == ISCSI_TASK_ABRT_TMF ||
557 task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
558 task->state == ISCSI_TASK_REQUEUE_SCSIQ)
559 return;
560 WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
561 task->state = state;
562
563 spin_lock_bh(&conn->taskqueuelock);
564 if (!list_empty(&task->running)) {
565 pr_debug_once("%s while task on list", __func__);
566 list_del_init(&task->running);
567 }
568 spin_unlock_bh(&conn->taskqueuelock);
569
570 if (conn->task == task)
571 conn->task = NULL;
572
573 if (conn->ping_task == task)
574 conn->ping_task = NULL;
575
576 /* release get from queueing */
577 __iscsi_put_task(task);
578}
579
580/**
581 * iscsi_complete_scsi_task - finish scsi task normally
582 * @task: iscsi task for scsi cmd
583 * @exp_cmdsn: expected cmd sn in cpu format
584 * @max_cmdsn: max cmd sn in cpu format
585 *
586 * This is used when drivers do not need or cannot perform
587 * lower level pdu processing.
588 *
589 * Called with session back_lock
590 */
591void iscsi_complete_scsi_task(struct iscsi_task *task,
592 uint32_t exp_cmdsn, uint32_t max_cmdsn)
593{
594 struct iscsi_conn *conn = task->conn;
595
596 ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
597
598 conn->last_recv = jiffies;
599 __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
600 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
601}
602EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
603
604
605/*
606 * session back_lock must be held and if not called for a task that is
607 * still pending or from the xmit thread, then xmit thread must
608 * be suspended.
609 */
610static void fail_scsi_task(struct iscsi_task *task, int err)
611{
612 struct iscsi_conn *conn = task->conn;
613 struct scsi_cmnd *sc;
614 int state;
615
616 /*
617 * if a command completes and we get a successful tmf response
618 * we will hit this because the scsi eh abort code does not take
619 * a ref to the task.
620 */
621 sc = task->sc;
622 if (!sc)
623 return;
624
625 if (task->state == ISCSI_TASK_PENDING) {
626 /*
627 * cmd never made it to the xmit thread, so we should not count
628 * the cmd in the sequencing
629 */
630 conn->session->queued_cmdsn--;
631 /* it was never sent so just complete like normal */
632 state = ISCSI_TASK_COMPLETED;
633 } else if (err == DID_TRANSPORT_DISRUPTED)
634 state = ISCSI_TASK_ABRT_SESS_RECOV;
635 else
636 state = ISCSI_TASK_ABRT_TMF;
637
638 sc->result = err << 16;
639 if (!scsi_bidi_cmnd(sc))
640 scsi_set_resid(sc, scsi_bufflen(sc));
641 else {
642 scsi_out(sc)->resid = scsi_out(sc)->length;
643 scsi_in(sc)->resid = scsi_in(sc)->length;
644 }
645
646 /* regular RX path uses back_lock */
647 spin_lock_bh(&conn->session->back_lock);
648 iscsi_complete_task(task, state);
649 spin_unlock_bh(&conn->session->back_lock);
650}
651
652static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
653 struct iscsi_task *task)
654{
655 struct iscsi_session *session = conn->session;
656 struct iscsi_hdr *hdr = task->hdr;
657 struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
658 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
659
660 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
661 return -ENOTCONN;
662
663 if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
664 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
665 /*
666 * pre-format CmdSN for outgoing PDU.
667 */
668 nop->cmdsn = cpu_to_be32(session->cmdsn);
669 if (hdr->itt != RESERVED_ITT) {
670 /*
671 * TODO: We always use immediate for normal session pdus.
672 * If we start to send tmfs or nops as non-immediate then
673 * we should start checking the cmdsn numbers for mgmt tasks.
674 *
675 * During discovery sessions iscsid sends TEXT as non immediate,
676 * but we always only send one PDU at a time.
677 */
678 if (conn->c_stage == ISCSI_CONN_STARTED &&
679 !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
680 session->queued_cmdsn++;
681 session->cmdsn++;
682 }
683 }
684
685 if (session->tt->init_task && session->tt->init_task(task))
686 return -EIO;
687
688 if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
689 session->state = ISCSI_STATE_LOGGING_OUT;
690
691 task->state = ISCSI_TASK_RUNNING;
692 ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
693 "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
694 hdr->itt, task->data_count);
695 return 0;
696}
697
698static struct iscsi_task *
699__iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
700 char *data, uint32_t data_size)
701{
702 struct iscsi_session *session = conn->session;
703 struct iscsi_host *ihost = shost_priv(session->host);
704 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
705 struct iscsi_task *task;
706 itt_t itt;
707
708 if (session->state == ISCSI_STATE_TERMINATE)
709 return NULL;
710
711 if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
712 /*
713 * Login and Text are sent serially, in
714 * request-followed-by-response sequence.
715 * Same task can be used. Same ITT must be used.
716 * Note that login_task is preallocated at conn_create().
717 */
718 if (conn->login_task->state != ISCSI_TASK_FREE) {
719 iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
720 "progress. Cannot start new task.\n");
721 return NULL;
722 }
723
724 if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
725 iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN);
726 return NULL;
727 }
728
729 task = conn->login_task;
730 } else {
731 if (session->state != ISCSI_STATE_LOGGED_IN)
732 return NULL;
733
734 if (data_size != 0) {
735 iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
736 return NULL;
737 }
738
739 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
740 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
741
742 if (!kfifo_out(&session->cmdpool.queue,
743 (void*)&task, sizeof(void*)))
744 return NULL;
745 }
746 /*
747 * released in complete pdu for task we expect a response for, and
748 * released by the lld when it has transmitted the task for
749 * pdus we do not expect a response for.
750 */
751 atomic_set(&task->refcount, 1);
752 task->conn = conn;
753 task->sc = NULL;
754 INIT_LIST_HEAD(&task->running);
755 task->state = ISCSI_TASK_PENDING;
756
757 if (data_size) {
758 memcpy(task->data, data, data_size);
759 task->data_count = data_size;
760 } else
761 task->data_count = 0;
762
763 if (conn->session->tt->alloc_pdu) {
764 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
765 iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
766 "pdu for mgmt task.\n");
767 goto free_task;
768 }
769 }
770
771 itt = task->hdr->itt;
772 task->hdr_len = sizeof(struct iscsi_hdr);
773 memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
774
775 if (hdr->itt != RESERVED_ITT) {
776 if (session->tt->parse_pdu_itt)
777 task->hdr->itt = itt;
778 else
779 task->hdr->itt = build_itt(task->itt,
780 task->conn->session->age);
781 }
782
783 if (!ihost->workq) {
784 if (iscsi_prep_mgmt_task(conn, task))
785 goto free_task;
786
787 if (session->tt->xmit_task(task))
788 goto free_task;
789 } else {
790 spin_lock_bh(&conn->taskqueuelock);
791 list_add_tail(&task->running, &conn->mgmtqueue);
792 spin_unlock_bh(&conn->taskqueuelock);
793 iscsi_conn_queue_work(conn);
794 }
795
796 return task;
797
798free_task:
799 /* regular RX path uses back_lock */
800 spin_lock(&session->back_lock);
801 __iscsi_put_task(task);
802 spin_unlock(&session->back_lock);
803 return NULL;
804}
805
806int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
807 char *data, uint32_t data_size)
808{
809 struct iscsi_conn *conn = cls_conn->dd_data;
810 struct iscsi_session *session = conn->session;
811 int err = 0;
812
813 spin_lock_bh(&session->frwd_lock);
814 if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
815 err = -EPERM;
816 spin_unlock_bh(&session->frwd_lock);
817 return err;
818}
819EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
820
821/**
822 * iscsi_cmd_rsp - SCSI Command Response processing
823 * @conn: iscsi connection
824 * @hdr: iscsi header
825 * @task: scsi command task
826 * @data: cmd data buffer
827 * @datalen: len of buffer
828 *
829 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
830 * then completes the command and task.
831 **/
832static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
833 struct iscsi_task *task, char *data,
834 int datalen)
835{
836 struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
837 struct iscsi_session *session = conn->session;
838 struct scsi_cmnd *sc = task->sc;
839
840 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
841 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
842
843 sc->result = (DID_OK << 16) | rhdr->cmd_status;
844
845 if (task->protected) {
846 sector_t sector;
847 u8 ascq;
848
849 /**
850 * Transports that didn't implement check_protection
851 * callback but still published T10-PI support to scsi-mid
852 * deserve this BUG_ON.
853 **/
854 BUG_ON(!session->tt->check_protection);
855
856 ascq = session->tt->check_protection(task, §or);
857 if (ascq) {
858 sc->result = DRIVER_SENSE << 24 |
859 SAM_STAT_CHECK_CONDITION;
860 scsi_build_sense_buffer(1, sc->sense_buffer,
861 ILLEGAL_REQUEST, 0x10, ascq);
862 scsi_set_sense_information(sc->sense_buffer,
863 SCSI_SENSE_BUFFERSIZE,
864 sector);
865 goto out;
866 }
867 }
868
869 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
870 sc->result = DID_ERROR << 16;
871 goto out;
872 }
873
874 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
875 uint16_t senselen;
876
877 if (datalen < 2) {
878invalid_datalen:
879 iscsi_conn_printk(KERN_ERR, conn,
880 "Got CHECK_CONDITION but invalid data "
881 "buffer size of %d\n", datalen);
882 sc->result = DID_BAD_TARGET << 16;
883 goto out;
884 }
885
886 senselen = get_unaligned_be16(data);
887 if (datalen < senselen)
888 goto invalid_datalen;
889
890 memcpy(sc->sense_buffer, data + 2,
891 min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
892 ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
893 min_t(uint16_t, senselen,
894 SCSI_SENSE_BUFFERSIZE));
895 }
896
897 if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
898 ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
899 int res_count = be32_to_cpu(rhdr->bi_residual_count);
900
901 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
902 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
903 res_count <= scsi_in(sc)->length))
904 scsi_in(sc)->resid = res_count;
905 else
906 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
907 }
908
909 if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
910 ISCSI_FLAG_CMD_OVERFLOW)) {
911 int res_count = be32_to_cpu(rhdr->residual_count);
912
913 if (res_count > 0 &&
914 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
915 res_count <= scsi_bufflen(sc)))
916 /* write side for bidi or uni-io set_resid */
917 scsi_set_resid(sc, res_count);
918 else
919 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
920 }
921out:
922 ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
923 sc, sc->result, task->itt);
924 conn->scsirsp_pdus_cnt++;
925 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
926}
927
928/**
929 * iscsi_data_in_rsp - SCSI Data-In Response processing
930 * @conn: iscsi connection
931 * @hdr: iscsi pdu
932 * @task: scsi command task
933 **/
934static void
935iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
936 struct iscsi_task *task)
937{
938 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
939 struct scsi_cmnd *sc = task->sc;
940
941 if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
942 return;
943
944 iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
945 sc->result = (DID_OK << 16) | rhdr->cmd_status;
946 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
947 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
948 ISCSI_FLAG_DATA_OVERFLOW)) {
949 int res_count = be32_to_cpu(rhdr->residual_count);
950
951 if (res_count > 0 &&
952 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
953 res_count <= scsi_in(sc)->length))
954 scsi_in(sc)->resid = res_count;
955 else
956 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
957 }
958
959 ISCSI_DBG_SESSION(conn->session, "data in with status done "
960 "[sc %p res %d itt 0x%x]\n",
961 sc, sc->result, task->itt);
962 conn->scsirsp_pdus_cnt++;
963 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
964}
965
966static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
967{
968 struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
969
970 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
971 conn->tmfrsp_pdus_cnt++;
972
973 if (conn->tmf_state != TMF_QUEUED)
974 return;
975
976 if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
977 conn->tmf_state = TMF_SUCCESS;
978 else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
979 conn->tmf_state = TMF_NOT_FOUND;
980 else
981 conn->tmf_state = TMF_FAILED;
982 wake_up(&conn->ehwait);
983}
984
985static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
986{
987 struct iscsi_nopout hdr;
988 struct iscsi_task *task;
989
990 if (!rhdr && conn->ping_task)
991 return -EINVAL;
992
993 memset(&hdr, 0, sizeof(struct iscsi_nopout));
994 hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
995 hdr.flags = ISCSI_FLAG_CMD_FINAL;
996
997 if (rhdr) {
998 hdr.lun = rhdr->lun;
999 hdr.ttt = rhdr->ttt;
1000 hdr.itt = RESERVED_ITT;
1001 } else
1002 hdr.ttt = RESERVED_ITT;
1003
1004 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
1005 if (!task) {
1006 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
1007 return -EIO;
1008 } else if (!rhdr) {
1009 /* only track our nops */
1010 conn->ping_task = task;
1011 conn->last_ping = jiffies;
1012 }
1013
1014 return 0;
1015}
1016
1017static int iscsi_nop_out_rsp(struct iscsi_task *task,
1018 struct iscsi_nopin *nop, char *data, int datalen)
1019{
1020 struct iscsi_conn *conn = task->conn;
1021 int rc = 0;
1022
1023 if (conn->ping_task != task) {
1024 /*
1025 * If this is not in response to one of our
1026 * nops then it must be from userspace.
1027 */
1028 if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
1029 data, datalen))
1030 rc = ISCSI_ERR_CONN_FAILED;
1031 } else
1032 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
1033 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1034 return rc;
1035}
1036
1037static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1038 char *data, int datalen)
1039{
1040 struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1041 struct iscsi_hdr rejected_pdu;
1042 int opcode, rc = 0;
1043
1044 conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1045
1046 if (ntoh24(reject->dlength) > datalen ||
1047 ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1048 iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1049 "pdu. Invalid data length (pdu dlength "
1050 "%u, datalen %d\n", ntoh24(reject->dlength),
1051 datalen);
1052 return ISCSI_ERR_PROTO;
1053 }
1054 memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1055 opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1056
1057 switch (reject->reason) {
1058 case ISCSI_REASON_DATA_DIGEST_ERROR:
1059 iscsi_conn_printk(KERN_ERR, conn,
1060 "pdu (op 0x%x itt 0x%x) rejected "
1061 "due to DataDigest error.\n",
1062 opcode, rejected_pdu.itt);
1063 break;
1064 case ISCSI_REASON_IMM_CMD_REJECT:
1065 iscsi_conn_printk(KERN_ERR, conn,
1066 "pdu (op 0x%x itt 0x%x) rejected. Too many "
1067 "immediate commands.\n",
1068 opcode, rejected_pdu.itt);
1069 /*
1070 * We only send one TMF at a time so if the target could not
1071 * handle it, then it should get fixed (RFC mandates that
1072 * a target can handle one immediate TMF per conn).
1073 *
1074 * For nops-outs, we could have sent more than one if
1075 * the target is sending us lots of nop-ins
1076 */
1077 if (opcode != ISCSI_OP_NOOP_OUT)
1078 return 0;
1079
1080 if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1081 /*
1082 * nop-out in response to target's nop-out rejected.
1083 * Just resend.
1084 */
1085 /* In RX path we are under back lock */
1086 spin_unlock(&conn->session->back_lock);
1087 spin_lock(&conn->session->frwd_lock);
1088 iscsi_send_nopout(conn,
1089 (struct iscsi_nopin*)&rejected_pdu);
1090 spin_unlock(&conn->session->frwd_lock);
1091 spin_lock(&conn->session->back_lock);
1092 } else {
1093 struct iscsi_task *task;
1094 /*
1095 * Our nop as ping got dropped. We know the target
1096 * and transport are ok so just clean up
1097 */
1098 task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1099 if (!task) {
1100 iscsi_conn_printk(KERN_ERR, conn,
1101 "Invalid pdu reject. Could "
1102 "not lookup rejected task.\n");
1103 rc = ISCSI_ERR_BAD_ITT;
1104 } else
1105 rc = iscsi_nop_out_rsp(task,
1106 (struct iscsi_nopin*)&rejected_pdu,
1107 NULL, 0);
1108 }
1109 break;
1110 default:
1111 iscsi_conn_printk(KERN_ERR, conn,
1112 "pdu (op 0x%x itt 0x%x) rejected. Reason "
1113 "code 0x%x\n", rejected_pdu.opcode,
1114 rejected_pdu.itt, reject->reason);
1115 break;
1116 }
1117 return rc;
1118}
1119
1120/**
1121 * iscsi_itt_to_task - look up task by itt
1122 * @conn: iscsi connection
1123 * @itt: itt
1124 *
1125 * This should be used for mgmt tasks like login and nops, or if
1126 * the LDD's itt space does not include the session age.
1127 *
1128 * The session back_lock must be held.
1129 */
1130struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1131{
1132 struct iscsi_session *session = conn->session;
1133 int i;
1134
1135 if (itt == RESERVED_ITT)
1136 return NULL;
1137
1138 if (session->tt->parse_pdu_itt)
1139 session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1140 else
1141 i = get_itt(itt);
1142 if (i >= session->cmds_max)
1143 return NULL;
1144
1145 return session->cmds[i];
1146}
1147EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1148
1149/**
1150 * __iscsi_complete_pdu - complete pdu
1151 * @conn: iscsi conn
1152 * @hdr: iscsi header
1153 * @data: data buffer
1154 * @datalen: len of data buffer
1155 *
1156 * Completes pdu processing by freeing any resources allocated at
1157 * queuecommand or send generic. session back_lock must be held and verify
1158 * itt must have been called.
1159 */
1160int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1161 char *data, int datalen)
1162{
1163 struct iscsi_session *session = conn->session;
1164 int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1165 struct iscsi_task *task;
1166 uint32_t itt;
1167
1168 conn->last_recv = jiffies;
1169 rc = iscsi_verify_itt(conn, hdr->itt);
1170 if (rc)
1171 return rc;
1172
1173 if (hdr->itt != RESERVED_ITT)
1174 itt = get_itt(hdr->itt);
1175 else
1176 itt = ~0U;
1177
1178 ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1179 opcode, conn->id, itt, datalen);
1180
1181 if (itt == ~0U) {
1182 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1183
1184 switch(opcode) {
1185 case ISCSI_OP_NOOP_IN:
1186 if (datalen) {
1187 rc = ISCSI_ERR_PROTO;
1188 break;
1189 }
1190
1191 if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1192 break;
1193
1194 /* In RX path we are under back lock */
1195 spin_unlock(&session->back_lock);
1196 spin_lock(&session->frwd_lock);
1197 iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1198 spin_unlock(&session->frwd_lock);
1199 spin_lock(&session->back_lock);
1200 break;
1201 case ISCSI_OP_REJECT:
1202 rc = iscsi_handle_reject(conn, hdr, data, datalen);
1203 break;
1204 case ISCSI_OP_ASYNC_EVENT:
1205 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1206 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1207 rc = ISCSI_ERR_CONN_FAILED;
1208 break;
1209 default:
1210 rc = ISCSI_ERR_BAD_OPCODE;
1211 break;
1212 }
1213 goto out;
1214 }
1215
1216 switch(opcode) {
1217 case ISCSI_OP_SCSI_CMD_RSP:
1218 case ISCSI_OP_SCSI_DATA_IN:
1219 task = iscsi_itt_to_ctask(conn, hdr->itt);
1220 if (!task)
1221 return ISCSI_ERR_BAD_ITT;
1222 task->last_xfer = jiffies;
1223 break;
1224 case ISCSI_OP_R2T:
1225 /*
1226 * LLD handles R2Ts if they need to.
1227 */
1228 return 0;
1229 case ISCSI_OP_LOGOUT_RSP:
1230 case ISCSI_OP_LOGIN_RSP:
1231 case ISCSI_OP_TEXT_RSP:
1232 case ISCSI_OP_SCSI_TMFUNC_RSP:
1233 case ISCSI_OP_NOOP_IN:
1234 task = iscsi_itt_to_task(conn, hdr->itt);
1235 if (!task)
1236 return ISCSI_ERR_BAD_ITT;
1237 break;
1238 default:
1239 return ISCSI_ERR_BAD_OPCODE;
1240 }
1241
1242 switch(opcode) {
1243 case ISCSI_OP_SCSI_CMD_RSP:
1244 iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1245 break;
1246 case ISCSI_OP_SCSI_DATA_IN:
1247 iscsi_data_in_rsp(conn, hdr, task);
1248 break;
1249 case ISCSI_OP_LOGOUT_RSP:
1250 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1251 if (datalen) {
1252 rc = ISCSI_ERR_PROTO;
1253 break;
1254 }
1255 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1256 goto recv_pdu;
1257 case ISCSI_OP_LOGIN_RSP:
1258 case ISCSI_OP_TEXT_RSP:
1259 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1260 /*
1261 * login related PDU's exp_statsn is handled in
1262 * userspace
1263 */
1264 goto recv_pdu;
1265 case ISCSI_OP_SCSI_TMFUNC_RSP:
1266 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1267 if (datalen) {
1268 rc = ISCSI_ERR_PROTO;
1269 break;
1270 }
1271
1272 iscsi_tmf_rsp(conn, hdr);
1273 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1274 break;
1275 case ISCSI_OP_NOOP_IN:
1276 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1277 if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1278 rc = ISCSI_ERR_PROTO;
1279 break;
1280 }
1281 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1282
1283 rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1284 data, datalen);
1285 break;
1286 default:
1287 rc = ISCSI_ERR_BAD_OPCODE;
1288 break;
1289 }
1290
1291out:
1292 return rc;
1293recv_pdu:
1294 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1295 rc = ISCSI_ERR_CONN_FAILED;
1296 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1297 return rc;
1298}
1299EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1300
1301int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1302 char *data, int datalen)
1303{
1304 int rc;
1305
1306 spin_lock(&conn->session->back_lock);
1307 rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1308 spin_unlock(&conn->session->back_lock);
1309 return rc;
1310}
1311EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1312
1313int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1314{
1315 struct iscsi_session *session = conn->session;
1316 int age = 0, i = 0;
1317
1318 if (itt == RESERVED_ITT)
1319 return 0;
1320
1321 if (session->tt->parse_pdu_itt)
1322 session->tt->parse_pdu_itt(conn, itt, &i, &age);
1323 else {
1324 i = get_itt(itt);
1325 age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1326 }
1327
1328 if (age != session->age) {
1329 iscsi_conn_printk(KERN_ERR, conn,
1330 "received itt %x expected session age (%x)\n",
1331 (__force u32)itt, session->age);
1332 return ISCSI_ERR_BAD_ITT;
1333 }
1334
1335 if (i >= session->cmds_max) {
1336 iscsi_conn_printk(KERN_ERR, conn,
1337 "received invalid itt index %u (max cmds "
1338 "%u.\n", i, session->cmds_max);
1339 return ISCSI_ERR_BAD_ITT;
1340 }
1341 return 0;
1342}
1343EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1344
1345/**
1346 * iscsi_itt_to_ctask - look up ctask by itt
1347 * @conn: iscsi connection
1348 * @itt: itt
1349 *
1350 * This should be used for cmd tasks.
1351 *
1352 * The session back_lock must be held.
1353 */
1354struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1355{
1356 struct iscsi_task *task;
1357
1358 if (iscsi_verify_itt(conn, itt))
1359 return NULL;
1360
1361 task = iscsi_itt_to_task(conn, itt);
1362 if (!task || !task->sc)
1363 return NULL;
1364
1365 if (task->sc->SCp.phase != conn->session->age) {
1366 iscsi_session_printk(KERN_ERR, conn->session,
1367 "task's session age %d, expected %d\n",
1368 task->sc->SCp.phase, conn->session->age);
1369 return NULL;
1370 }
1371
1372 return task;
1373}
1374EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1375
1376void iscsi_session_failure(struct iscsi_session *session,
1377 enum iscsi_err err)
1378{
1379 struct iscsi_conn *conn;
1380 struct device *dev;
1381
1382 spin_lock_bh(&session->frwd_lock);
1383 conn = session->leadconn;
1384 if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1385 spin_unlock_bh(&session->frwd_lock);
1386 return;
1387 }
1388
1389 dev = get_device(&conn->cls_conn->dev);
1390 spin_unlock_bh(&session->frwd_lock);
1391 if (!dev)
1392 return;
1393 /*
1394 * if the host is being removed bypass the connection
1395 * recovery initialization because we are going to kill
1396 * the session.
1397 */
1398 if (err == ISCSI_ERR_INVALID_HOST)
1399 iscsi_conn_error_event(conn->cls_conn, err);
1400 else
1401 iscsi_conn_failure(conn, err);
1402 put_device(dev);
1403}
1404EXPORT_SYMBOL_GPL(iscsi_session_failure);
1405
1406void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1407{
1408 struct iscsi_session *session = conn->session;
1409
1410 spin_lock_bh(&session->frwd_lock);
1411 if (session->state == ISCSI_STATE_FAILED) {
1412 spin_unlock_bh(&session->frwd_lock);
1413 return;
1414 }
1415
1416 if (conn->stop_stage == 0)
1417 session->state = ISCSI_STATE_FAILED;
1418 spin_unlock_bh(&session->frwd_lock);
1419
1420 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1421 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1422 iscsi_conn_error_event(conn->cls_conn, err);
1423}
1424EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1425
1426static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1427{
1428 struct iscsi_session *session = conn->session;
1429
1430 /*
1431 * Check for iSCSI window and take care of CmdSN wrap-around
1432 */
1433 if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1434 ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1435 "%u MaxCmdSN %u CmdSN %u/%u\n",
1436 session->exp_cmdsn, session->max_cmdsn,
1437 session->cmdsn, session->queued_cmdsn);
1438 return -ENOSPC;
1439 }
1440 return 0;
1441}
1442
1443static int iscsi_xmit_task(struct iscsi_conn *conn)
1444{
1445 struct iscsi_task *task = conn->task;
1446 int rc;
1447
1448 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
1449 return -ENODATA;
1450
1451 __iscsi_get_task(task);
1452 spin_unlock_bh(&conn->session->frwd_lock);
1453 rc = conn->session->tt->xmit_task(task);
1454 spin_lock_bh(&conn->session->frwd_lock);
1455 if (!rc) {
1456 /* done with this task */
1457 task->last_xfer = jiffies;
1458 conn->task = NULL;
1459 }
1460 /* regular RX path uses back_lock */
1461 spin_lock(&conn->session->back_lock);
1462 __iscsi_put_task(task);
1463 spin_unlock(&conn->session->back_lock);
1464 return rc;
1465}
1466
1467/**
1468 * iscsi_requeue_task - requeue task to run from session workqueue
1469 * @task: task to requeue
1470 *
1471 * LLDs that need to run a task from the session workqueue should call
1472 * this. The session frwd_lock must be held. This should only be called
1473 * by software drivers.
1474 */
1475void iscsi_requeue_task(struct iscsi_task *task)
1476{
1477 struct iscsi_conn *conn = task->conn;
1478
1479 /*
1480 * this may be on the requeue list already if the xmit_task callout
1481 * is handling the r2ts while we are adding new ones
1482 */
1483 spin_lock_bh(&conn->taskqueuelock);
1484 if (list_empty(&task->running))
1485 list_add_tail(&task->running, &conn->requeue);
1486 spin_unlock_bh(&conn->taskqueuelock);
1487 iscsi_conn_queue_work(conn);
1488}
1489EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1490
1491/**
1492 * iscsi_data_xmit - xmit any command into the scheduled connection
1493 * @conn: iscsi connection
1494 *
1495 * Notes:
1496 * The function can return -EAGAIN in which case the caller must
1497 * re-schedule it again later or recover. '0' return code means
1498 * successful xmit.
1499 **/
1500static int iscsi_data_xmit(struct iscsi_conn *conn)
1501{
1502 struct iscsi_task *task;
1503 int rc = 0;
1504
1505 spin_lock_bh(&conn->session->frwd_lock);
1506 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1507 ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1508 spin_unlock_bh(&conn->session->frwd_lock);
1509 return -ENODATA;
1510 }
1511
1512 if (conn->task) {
1513 rc = iscsi_xmit_task(conn);
1514 if (rc)
1515 goto done;
1516 }
1517
1518 /*
1519 * process mgmt pdus like nops before commands since we should
1520 * only have one nop-out as a ping from us and targets should not
1521 * overflow us with nop-ins
1522 */
1523 spin_lock_bh(&conn->taskqueuelock);
1524check_mgmt:
1525 while (!list_empty(&conn->mgmtqueue)) {
1526 conn->task = list_entry(conn->mgmtqueue.next,
1527 struct iscsi_task, running);
1528 list_del_init(&conn->task->running);
1529 spin_unlock_bh(&conn->taskqueuelock);
1530 if (iscsi_prep_mgmt_task(conn, conn->task)) {
1531 /* regular RX path uses back_lock */
1532 spin_lock_bh(&conn->session->back_lock);
1533 __iscsi_put_task(conn->task);
1534 spin_unlock_bh(&conn->session->back_lock);
1535 conn->task = NULL;
1536 spin_lock_bh(&conn->taskqueuelock);
1537 continue;
1538 }
1539 rc = iscsi_xmit_task(conn);
1540 if (rc)
1541 goto done;
1542 spin_lock_bh(&conn->taskqueuelock);
1543 }
1544
1545 /* process pending command queue */
1546 while (!list_empty(&conn->cmdqueue)) {
1547 conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1548 running);
1549 list_del_init(&conn->task->running);
1550 spin_unlock_bh(&conn->taskqueuelock);
1551 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1552 fail_scsi_task(conn->task, DID_IMM_RETRY);
1553 spin_lock_bh(&conn->taskqueuelock);
1554 continue;
1555 }
1556 rc = iscsi_prep_scsi_cmd_pdu(conn->task);
1557 if (rc) {
1558 if (rc == -ENOMEM || rc == -EACCES) {
1559 spin_lock_bh(&conn->taskqueuelock);
1560 list_add_tail(&conn->task->running,
1561 &conn->cmdqueue);
1562 conn->task = NULL;
1563 spin_unlock_bh(&conn->taskqueuelock);
1564 goto done;
1565 } else
1566 fail_scsi_task(conn->task, DID_ABORT);
1567 spin_lock_bh(&conn->taskqueuelock);
1568 continue;
1569 }
1570 rc = iscsi_xmit_task(conn);
1571 if (rc)
1572 goto done;
1573 /*
1574 * we could continuously get new task requests so
1575 * we need to check the mgmt queue for nops that need to
1576 * be sent to aviod starvation
1577 */
1578 spin_lock_bh(&conn->taskqueuelock);
1579 if (!list_empty(&conn->mgmtqueue))
1580 goto check_mgmt;
1581 }
1582
1583 while (!list_empty(&conn->requeue)) {
1584 /*
1585 * we always do fastlogout - conn stop code will clean up.
1586 */
1587 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1588 break;
1589
1590 task = list_entry(conn->requeue.next, struct iscsi_task,
1591 running);
1592 if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1593 break;
1594
1595 conn->task = task;
1596 list_del_init(&conn->task->running);
1597 conn->task->state = ISCSI_TASK_RUNNING;
1598 spin_unlock_bh(&conn->taskqueuelock);
1599 rc = iscsi_xmit_task(conn);
1600 if (rc)
1601 goto done;
1602 spin_lock_bh(&conn->taskqueuelock);
1603 if (!list_empty(&conn->mgmtqueue))
1604 goto check_mgmt;
1605 }
1606 spin_unlock_bh(&conn->taskqueuelock);
1607 spin_unlock_bh(&conn->session->frwd_lock);
1608 return -ENODATA;
1609
1610done:
1611 spin_unlock_bh(&conn->session->frwd_lock);
1612 return rc;
1613}
1614
1615static void iscsi_xmitworker(struct work_struct *work)
1616{
1617 struct iscsi_conn *conn =
1618 container_of(work, struct iscsi_conn, xmitwork);
1619 int rc;
1620 /*
1621 * serialize Xmit worker on a per-connection basis.
1622 */
1623 do {
1624 rc = iscsi_data_xmit(conn);
1625 } while (rc >= 0 || rc == -EAGAIN);
1626}
1627
1628static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1629 struct scsi_cmnd *sc)
1630{
1631 struct iscsi_task *task;
1632
1633 if (!kfifo_out(&conn->session->cmdpool.queue,
1634 (void *) &task, sizeof(void *)))
1635 return NULL;
1636
1637 sc->SCp.phase = conn->session->age;
1638 sc->SCp.ptr = (char *) task;
1639
1640 atomic_set(&task->refcount, 1);
1641 task->state = ISCSI_TASK_PENDING;
1642 task->conn = conn;
1643 task->sc = sc;
1644 task->have_checked_conn = false;
1645 task->last_timeout = jiffies;
1646 task->last_xfer = jiffies;
1647 task->protected = false;
1648 INIT_LIST_HEAD(&task->running);
1649 return task;
1650}
1651
1652enum {
1653 FAILURE_BAD_HOST = 1,
1654 FAILURE_SESSION_FAILED,
1655 FAILURE_SESSION_FREED,
1656 FAILURE_WINDOW_CLOSED,
1657 FAILURE_OOM,
1658 FAILURE_SESSION_TERMINATE,
1659 FAILURE_SESSION_IN_RECOVERY,
1660 FAILURE_SESSION_RECOVERY_TIMEOUT,
1661 FAILURE_SESSION_LOGGING_OUT,
1662 FAILURE_SESSION_NOT_READY,
1663};
1664
1665int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1666{
1667 struct iscsi_cls_session *cls_session;
1668 struct iscsi_host *ihost;
1669 int reason = 0;
1670 struct iscsi_session *session;
1671 struct iscsi_conn *conn;
1672 struct iscsi_task *task = NULL;
1673
1674 sc->result = 0;
1675 sc->SCp.ptr = NULL;
1676
1677 ihost = shost_priv(host);
1678
1679 cls_session = starget_to_session(scsi_target(sc->device));
1680 session = cls_session->dd_data;
1681 spin_lock_bh(&session->frwd_lock);
1682
1683 reason = iscsi_session_chkready(cls_session);
1684 if (reason) {
1685 sc->result = reason;
1686 goto fault;
1687 }
1688
1689 if (session->state != ISCSI_STATE_LOGGED_IN) {
1690 /*
1691 * to handle the race between when we set the recovery state
1692 * and block the session we requeue here (commands could
1693 * be entering our queuecommand while a block is starting
1694 * up because the block code is not locked)
1695 */
1696 switch (session->state) {
1697 case ISCSI_STATE_FAILED:
1698 case ISCSI_STATE_IN_RECOVERY:
1699 reason = FAILURE_SESSION_IN_RECOVERY;
1700 sc->result = DID_IMM_RETRY << 16;
1701 break;
1702 case ISCSI_STATE_LOGGING_OUT:
1703 reason = FAILURE_SESSION_LOGGING_OUT;
1704 sc->result = DID_IMM_RETRY << 16;
1705 break;
1706 case ISCSI_STATE_RECOVERY_FAILED:
1707 reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1708 sc->result = DID_TRANSPORT_FAILFAST << 16;
1709 break;
1710 case ISCSI_STATE_TERMINATE:
1711 reason = FAILURE_SESSION_TERMINATE;
1712 sc->result = DID_NO_CONNECT << 16;
1713 break;
1714 default:
1715 reason = FAILURE_SESSION_FREED;
1716 sc->result = DID_NO_CONNECT << 16;
1717 }
1718 goto fault;
1719 }
1720
1721 conn = session->leadconn;
1722 if (!conn) {
1723 reason = FAILURE_SESSION_FREED;
1724 sc->result = DID_NO_CONNECT << 16;
1725 goto fault;
1726 }
1727
1728 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1729 reason = FAILURE_SESSION_IN_RECOVERY;
1730 sc->result = DID_REQUEUE;
1731 goto fault;
1732 }
1733
1734 if (iscsi_check_cmdsn_window_closed(conn)) {
1735 reason = FAILURE_WINDOW_CLOSED;
1736 goto reject;
1737 }
1738
1739 task = iscsi_alloc_task(conn, sc);
1740 if (!task) {
1741 reason = FAILURE_OOM;
1742 goto reject;
1743 }
1744
1745 if (!ihost->workq) {
1746 reason = iscsi_prep_scsi_cmd_pdu(task);
1747 if (reason) {
1748 if (reason == -ENOMEM || reason == -EACCES) {
1749 reason = FAILURE_OOM;
1750 goto prepd_reject;
1751 } else {
1752 sc->result = DID_ABORT << 16;
1753 goto prepd_fault;
1754 }
1755 }
1756 if (session->tt->xmit_task(task)) {
1757 session->cmdsn--;
1758 reason = FAILURE_SESSION_NOT_READY;
1759 goto prepd_reject;
1760 }
1761 } else {
1762 spin_lock_bh(&conn->taskqueuelock);
1763 list_add_tail(&task->running, &conn->cmdqueue);
1764 spin_unlock_bh(&conn->taskqueuelock);
1765 iscsi_conn_queue_work(conn);
1766 }
1767
1768 session->queued_cmdsn++;
1769 spin_unlock_bh(&session->frwd_lock);
1770 return 0;
1771
1772prepd_reject:
1773 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1774reject:
1775 spin_unlock_bh(&session->frwd_lock);
1776 ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1777 sc->cmnd[0], reason);
1778 return SCSI_MLQUEUE_TARGET_BUSY;
1779
1780prepd_fault:
1781 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1782fault:
1783 spin_unlock_bh(&session->frwd_lock);
1784 ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1785 sc->cmnd[0], reason);
1786 if (!scsi_bidi_cmnd(sc))
1787 scsi_set_resid(sc, scsi_bufflen(sc));
1788 else {
1789 scsi_out(sc)->resid = scsi_out(sc)->length;
1790 scsi_in(sc)->resid = scsi_in(sc)->length;
1791 }
1792 sc->scsi_done(sc);
1793 return 0;
1794}
1795EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1796
1797int iscsi_target_alloc(struct scsi_target *starget)
1798{
1799 struct iscsi_cls_session *cls_session = starget_to_session(starget);
1800 struct iscsi_session *session = cls_session->dd_data;
1801
1802 starget->can_queue = session->scsi_cmds_max;
1803 return 0;
1804}
1805EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1806
1807static void iscsi_tmf_timedout(unsigned long data)
1808{
1809 struct iscsi_conn *conn = (struct iscsi_conn *)data;
1810 struct iscsi_session *session = conn->session;
1811
1812 spin_lock(&session->frwd_lock);
1813 if (conn->tmf_state == TMF_QUEUED) {
1814 conn->tmf_state = TMF_TIMEDOUT;
1815 ISCSI_DBG_EH(session, "tmf timedout\n");
1816 /* unblock eh_abort() */
1817 wake_up(&conn->ehwait);
1818 }
1819 spin_unlock(&session->frwd_lock);
1820}
1821
1822static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1823 struct iscsi_tm *hdr, int age,
1824 int timeout)
1825{
1826 struct iscsi_session *session = conn->session;
1827 struct iscsi_task *task;
1828
1829 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1830 NULL, 0);
1831 if (!task) {
1832 spin_unlock_bh(&session->frwd_lock);
1833 iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1834 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1835 spin_lock_bh(&session->frwd_lock);
1836 return -EPERM;
1837 }
1838 conn->tmfcmd_pdus_cnt++;
1839 conn->tmf_timer.expires = timeout * HZ + jiffies;
1840 conn->tmf_timer.function = iscsi_tmf_timedout;
1841 conn->tmf_timer.data = (unsigned long)conn;
1842 add_timer(&conn->tmf_timer);
1843 ISCSI_DBG_EH(session, "tmf set timeout\n");
1844
1845 spin_unlock_bh(&session->frwd_lock);
1846 mutex_unlock(&session->eh_mutex);
1847
1848 /*
1849 * block eh thread until:
1850 *
1851 * 1) tmf response
1852 * 2) tmf timeout
1853 * 3) session is terminated or restarted or userspace has
1854 * given up on recovery
1855 */
1856 wait_event_interruptible(conn->ehwait, age != session->age ||
1857 session->state != ISCSI_STATE_LOGGED_IN ||
1858 conn->tmf_state != TMF_QUEUED);
1859 if (signal_pending(current))
1860 flush_signals(current);
1861 del_timer_sync(&conn->tmf_timer);
1862
1863 mutex_lock(&session->eh_mutex);
1864 spin_lock_bh(&session->frwd_lock);
1865 /* if the session drops it will clean up the task */
1866 if (age != session->age ||
1867 session->state != ISCSI_STATE_LOGGED_IN)
1868 return -ENOTCONN;
1869 return 0;
1870}
1871
1872/*
1873 * Fail commands. session lock held and recv side suspended and xmit
1874 * thread flushed
1875 */
1876static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error)
1877{
1878 struct iscsi_task *task;
1879 int i;
1880
1881 for (i = 0; i < conn->session->cmds_max; i++) {
1882 task = conn->session->cmds[i];
1883 if (!task->sc || task->state == ISCSI_TASK_FREE)
1884 continue;
1885
1886 if (lun != -1 && lun != task->sc->device->lun)
1887 continue;
1888
1889 ISCSI_DBG_SESSION(conn->session,
1890 "failing sc %p itt 0x%x state %d\n",
1891 task->sc, task->itt, task->state);
1892 fail_scsi_task(task, error);
1893 }
1894}
1895
1896/**
1897 * iscsi_suspend_queue - suspend iscsi_queuecommand
1898 * @conn: iscsi conn to stop queueing IO on
1899 *
1900 * This grabs the session frwd_lock to make sure no one is in
1901 * xmit_task/queuecommand, and then sets suspend to prevent
1902 * new commands from being queued. This only needs to be called
1903 * by offload drivers that need to sync a path like ep disconnect
1904 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1905 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1906 */
1907void iscsi_suspend_queue(struct iscsi_conn *conn)
1908{
1909 spin_lock_bh(&conn->session->frwd_lock);
1910 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1911 spin_unlock_bh(&conn->session->frwd_lock);
1912}
1913EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1914
1915/**
1916 * iscsi_suspend_tx - suspend iscsi_data_xmit
1917 * @conn: iscsi conn tp stop processing IO on.
1918 *
1919 * This function sets the suspend bit to prevent iscsi_data_xmit
1920 * from sending new IO, and if work is queued on the xmit thread
1921 * it will wait for it to be completed.
1922 */
1923void iscsi_suspend_tx(struct iscsi_conn *conn)
1924{
1925 struct Scsi_Host *shost = conn->session->host;
1926 struct iscsi_host *ihost = shost_priv(shost);
1927
1928 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1929 if (ihost->workq)
1930 flush_workqueue(ihost->workq);
1931}
1932EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1933
1934static void iscsi_start_tx(struct iscsi_conn *conn)
1935{
1936 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1937 iscsi_conn_queue_work(conn);
1938}
1939
1940/*
1941 * We want to make sure a ping is in flight. It has timed out.
1942 * And we are not busy processing a pdu that is making
1943 * progress but got started before the ping and is taking a while
1944 * to complete so the ping is just stuck behind it in a queue.
1945 */
1946static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1947{
1948 if (conn->ping_task &&
1949 time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1950 (conn->ping_timeout * HZ), jiffies))
1951 return 1;
1952 else
1953 return 0;
1954}
1955
1956static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1957{
1958 enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
1959 struct iscsi_task *task = NULL, *running_task;
1960 struct iscsi_cls_session *cls_session;
1961 struct iscsi_session *session;
1962 struct iscsi_conn *conn;
1963 int i;
1964
1965 cls_session = starget_to_session(scsi_target(sc->device));
1966 session = cls_session->dd_data;
1967
1968 ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1969
1970 spin_lock(&session->frwd_lock);
1971 task = (struct iscsi_task *)sc->SCp.ptr;
1972 if (!task) {
1973 /*
1974 * Raced with completion. Blk layer has taken ownership
1975 * so let timeout code complete it now.
1976 */
1977 rc = BLK_EH_HANDLED;
1978 goto done;
1979 }
1980
1981 if (session->state != ISCSI_STATE_LOGGED_IN) {
1982 /*
1983 * We are probably in the middle of iscsi recovery so let
1984 * that complete and handle the error.
1985 */
1986 rc = BLK_EH_RESET_TIMER;
1987 goto done;
1988 }
1989
1990 conn = session->leadconn;
1991 if (!conn) {
1992 /* In the middle of shuting down */
1993 rc = BLK_EH_RESET_TIMER;
1994 goto done;
1995 }
1996
1997 /*
1998 * If we have sent (at least queued to the network layer) a pdu or
1999 * recvd one for the task since the last timeout ask for
2000 * more time. If on the next timeout we have not made progress
2001 * we can check if it is the task or connection when we send the
2002 * nop as a ping.
2003 */
2004 if (time_after(task->last_xfer, task->last_timeout)) {
2005 ISCSI_DBG_EH(session, "Command making progress. Asking "
2006 "scsi-ml for more time to complete. "
2007 "Last data xfer at %lu. Last timeout was at "
2008 "%lu\n.", task->last_xfer, task->last_timeout);
2009 task->have_checked_conn = false;
2010 rc = BLK_EH_RESET_TIMER;
2011 goto done;
2012 }
2013
2014 if (!conn->recv_timeout && !conn->ping_timeout)
2015 goto done;
2016 /*
2017 * if the ping timedout then we are in the middle of cleaning up
2018 * and can let the iscsi eh handle it
2019 */
2020 if (iscsi_has_ping_timed_out(conn)) {
2021 rc = BLK_EH_RESET_TIMER;
2022 goto done;
2023 }
2024
2025 for (i = 0; i < conn->session->cmds_max; i++) {
2026 running_task = conn->session->cmds[i];
2027 if (!running_task->sc || running_task == task ||
2028 running_task->state != ISCSI_TASK_RUNNING)
2029 continue;
2030
2031 /*
2032 * Only check if cmds started before this one have made
2033 * progress, or this could never fail
2034 */
2035 if (time_after(running_task->sc->jiffies_at_alloc,
2036 task->sc->jiffies_at_alloc))
2037 continue;
2038
2039 if (time_after(running_task->last_xfer, task->last_timeout)) {
2040 /*
2041 * This task has not made progress, but a task
2042 * started before us has transferred data since
2043 * we started/last-checked. We could be queueing
2044 * too many tasks or the LU is bad.
2045 *
2046 * If the device is bad the cmds ahead of us on
2047 * other devs will complete, and this loop will
2048 * eventually fail starting the scsi eh.
2049 */
2050 ISCSI_DBG_EH(session, "Command has not made progress "
2051 "but commands ahead of it have. "
2052 "Asking scsi-ml for more time to "
2053 "complete. Our last xfer vs running task "
2054 "last xfer %lu/%lu. Last check %lu.\n",
2055 task->last_xfer, running_task->last_xfer,
2056 task->last_timeout);
2057 rc = BLK_EH_RESET_TIMER;
2058 goto done;
2059 }
2060 }
2061
2062 /* Assumes nop timeout is shorter than scsi cmd timeout */
2063 if (task->have_checked_conn)
2064 goto done;
2065
2066 /*
2067 * Checking the transport already or nop from a cmd timeout still
2068 * running
2069 */
2070 if (conn->ping_task) {
2071 task->have_checked_conn = true;
2072 rc = BLK_EH_RESET_TIMER;
2073 goto done;
2074 }
2075
2076 /* Make sure there is a transport check done */
2077 iscsi_send_nopout(conn, NULL);
2078 task->have_checked_conn = true;
2079 rc = BLK_EH_RESET_TIMER;
2080
2081done:
2082 if (task)
2083 task->last_timeout = jiffies;
2084 spin_unlock(&session->frwd_lock);
2085 ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2086 "timer reset" : "nh");
2087 return rc;
2088}
2089
2090static void iscsi_check_transport_timeouts(unsigned long data)
2091{
2092 struct iscsi_conn *conn = (struct iscsi_conn *)data;
2093 struct iscsi_session *session = conn->session;
2094 unsigned long recv_timeout, next_timeout = 0, last_recv;
2095
2096 spin_lock(&session->frwd_lock);
2097 if (session->state != ISCSI_STATE_LOGGED_IN)
2098 goto done;
2099
2100 recv_timeout = conn->recv_timeout;
2101 if (!recv_timeout)
2102 goto done;
2103
2104 recv_timeout *= HZ;
2105 last_recv = conn->last_recv;
2106
2107 if (iscsi_has_ping_timed_out(conn)) {
2108 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2109 "expired, recv timeout %d, last rx %lu, "
2110 "last ping %lu, now %lu\n",
2111 conn->ping_timeout, conn->recv_timeout,
2112 last_recv, conn->last_ping, jiffies);
2113 spin_unlock(&session->frwd_lock);
2114 iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT);
2115 return;
2116 }
2117
2118 if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2119 /* send a ping to try to provoke some traffic */
2120 ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2121 if (iscsi_send_nopout(conn, NULL))
2122 next_timeout = jiffies + (1 * HZ);
2123 else
2124 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2125 } else
2126 next_timeout = last_recv + recv_timeout;
2127
2128 ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2129 mod_timer(&conn->transport_timer, next_timeout);
2130done:
2131 spin_unlock(&session->frwd_lock);
2132}
2133
2134static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2135 struct iscsi_tm *hdr)
2136{
2137 memset(hdr, 0, sizeof(*hdr));
2138 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2139 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2140 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2141 hdr->lun = task->lun;
2142 hdr->rtt = task->hdr_itt;
2143 hdr->refcmdsn = task->cmdsn;
2144}
2145
2146int iscsi_eh_abort(struct scsi_cmnd *sc)
2147{
2148 struct iscsi_cls_session *cls_session;
2149 struct iscsi_session *session;
2150 struct iscsi_conn *conn;
2151 struct iscsi_task *task;
2152 struct iscsi_tm *hdr;
2153 int age;
2154
2155 cls_session = starget_to_session(scsi_target(sc->device));
2156 session = cls_session->dd_data;
2157
2158 ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2159
2160 mutex_lock(&session->eh_mutex);
2161 spin_lock_bh(&session->frwd_lock);
2162 /*
2163 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2164 * got the command.
2165 */
2166 if (!sc->SCp.ptr) {
2167 ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2168 "it completed.\n");
2169 spin_unlock_bh(&session->frwd_lock);
2170 mutex_unlock(&session->eh_mutex);
2171 return SUCCESS;
2172 }
2173
2174 /*
2175 * If we are not logged in or we have started a new session
2176 * then let the host reset code handle this
2177 */
2178 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2179 sc->SCp.phase != session->age) {
2180 spin_unlock_bh(&session->frwd_lock);
2181 mutex_unlock(&session->eh_mutex);
2182 ISCSI_DBG_EH(session, "failing abort due to dropped "
2183 "session.\n");
2184 return FAILED;
2185 }
2186
2187 conn = session->leadconn;
2188 conn->eh_abort_cnt++;
2189 age = session->age;
2190
2191 task = (struct iscsi_task *)sc->SCp.ptr;
2192 ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
2193 sc, task->itt);
2194
2195 /* task completed before time out */
2196 if (!task->sc) {
2197 ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2198 goto success;
2199 }
2200
2201 if (task->state == ISCSI_TASK_PENDING) {
2202 fail_scsi_task(task, DID_ABORT);
2203 goto success;
2204 }
2205
2206 /* only have one tmf outstanding at a time */
2207 if (conn->tmf_state != TMF_INITIAL)
2208 goto failed;
2209 conn->tmf_state = TMF_QUEUED;
2210
2211 hdr = &conn->tmhdr;
2212 iscsi_prep_abort_task_pdu(task, hdr);
2213
2214 if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout))
2215 goto failed;
2216
2217 switch (conn->tmf_state) {
2218 case TMF_SUCCESS:
2219 spin_unlock_bh(&session->frwd_lock);
2220 /*
2221 * stop tx side incase the target had sent a abort rsp but
2222 * the initiator was still writing out data.
2223 */
2224 iscsi_suspend_tx(conn);
2225 /*
2226 * we do not stop the recv side because targets have been
2227 * good and have never sent us a successful tmf response
2228 * then sent more data for the cmd.
2229 */
2230 spin_lock_bh(&session->frwd_lock);
2231 fail_scsi_task(task, DID_ABORT);
2232 conn->tmf_state = TMF_INITIAL;
2233 memset(hdr, 0, sizeof(*hdr));
2234 spin_unlock_bh(&session->frwd_lock);
2235 iscsi_start_tx(conn);
2236 goto success_unlocked;
2237 case TMF_TIMEDOUT:
2238 spin_unlock_bh(&session->frwd_lock);
2239 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2240 goto failed_unlocked;
2241 case TMF_NOT_FOUND:
2242 if (!sc->SCp.ptr) {
2243 conn->tmf_state = TMF_INITIAL;
2244 memset(hdr, 0, sizeof(*hdr));
2245 /* task completed before tmf abort response */
2246 ISCSI_DBG_EH(session, "sc completed while abort in "
2247 "progress\n");
2248 goto success;
2249 }
2250 /* fall through */
2251 default:
2252 conn->tmf_state = TMF_INITIAL;
2253 goto failed;
2254 }
2255
2256success:
2257 spin_unlock_bh(&session->frwd_lock);
2258success_unlocked:
2259 ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2260 sc, task->itt);
2261 mutex_unlock(&session->eh_mutex);
2262 return SUCCESS;
2263
2264failed:
2265 spin_unlock_bh(&session->frwd_lock);
2266failed_unlocked:
2267 ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2268 task ? task->itt : 0);
2269 mutex_unlock(&session->eh_mutex);
2270 return FAILED;
2271}
2272EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2273
2274static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2275{
2276 memset(hdr, 0, sizeof(*hdr));
2277 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2278 hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2279 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2280 int_to_scsilun(sc->device->lun, &hdr->lun);
2281 hdr->rtt = RESERVED_ITT;
2282}
2283
2284int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2285{
2286 struct iscsi_cls_session *cls_session;
2287 struct iscsi_session *session;
2288 struct iscsi_conn *conn;
2289 struct iscsi_tm *hdr;
2290 int rc = FAILED;
2291
2292 cls_session = starget_to_session(scsi_target(sc->device));
2293 session = cls_session->dd_data;
2294
2295 ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc,
2296 sc->device->lun);
2297
2298 mutex_lock(&session->eh_mutex);
2299 spin_lock_bh(&session->frwd_lock);
2300 /*
2301 * Just check if we are not logged in. We cannot check for
2302 * the phase because the reset could come from a ioctl.
2303 */
2304 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2305 goto unlock;
2306 conn = session->leadconn;
2307
2308 /* only have one tmf outstanding at a time */
2309 if (conn->tmf_state != TMF_INITIAL)
2310 goto unlock;
2311 conn->tmf_state = TMF_QUEUED;
2312
2313 hdr = &conn->tmhdr;
2314 iscsi_prep_lun_reset_pdu(sc, hdr);
2315
2316 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2317 session->lu_reset_timeout)) {
2318 rc = FAILED;
2319 goto unlock;
2320 }
2321
2322 switch (conn->tmf_state) {
2323 case TMF_SUCCESS:
2324 break;
2325 case TMF_TIMEDOUT:
2326 spin_unlock_bh(&session->frwd_lock);
2327 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2328 goto done;
2329 default:
2330 conn->tmf_state = TMF_INITIAL;
2331 goto unlock;
2332 }
2333
2334 rc = SUCCESS;
2335 spin_unlock_bh(&session->frwd_lock);
2336
2337 iscsi_suspend_tx(conn);
2338
2339 spin_lock_bh(&session->frwd_lock);
2340 memset(hdr, 0, sizeof(*hdr));
2341 fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2342 conn->tmf_state = TMF_INITIAL;
2343 spin_unlock_bh(&session->frwd_lock);
2344
2345 iscsi_start_tx(conn);
2346 goto done;
2347
2348unlock:
2349 spin_unlock_bh(&session->frwd_lock);
2350done:
2351 ISCSI_DBG_EH(session, "dev reset result = %s\n",
2352 rc == SUCCESS ? "SUCCESS" : "FAILED");
2353 mutex_unlock(&session->eh_mutex);
2354 return rc;
2355}
2356EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2357
2358void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2359{
2360 struct iscsi_session *session = cls_session->dd_data;
2361
2362 spin_lock_bh(&session->frwd_lock);
2363 if (session->state != ISCSI_STATE_LOGGED_IN) {
2364 session->state = ISCSI_STATE_RECOVERY_FAILED;
2365 if (session->leadconn)
2366 wake_up(&session->leadconn->ehwait);
2367 }
2368 spin_unlock_bh(&session->frwd_lock);
2369}
2370EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2371
2372/**
2373 * iscsi_eh_session_reset - drop session and attempt relogin
2374 * @sc: scsi command
2375 *
2376 * This function will wait for a relogin, session termination from
2377 * userspace, or a recovery/replacement timeout.
2378 */
2379int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2380{
2381 struct iscsi_cls_session *cls_session;
2382 struct iscsi_session *session;
2383 struct iscsi_conn *conn;
2384
2385 cls_session = starget_to_session(scsi_target(sc->device));
2386 session = cls_session->dd_data;
2387 conn = session->leadconn;
2388
2389 mutex_lock(&session->eh_mutex);
2390 spin_lock_bh(&session->frwd_lock);
2391 if (session->state == ISCSI_STATE_TERMINATE) {
2392failed:
2393 ISCSI_DBG_EH(session,
2394 "failing session reset: Could not log back into "
2395 "%s, %s [age %d]\n", session->targetname,
2396 conn->persistent_address, session->age);
2397 spin_unlock_bh(&session->frwd_lock);
2398 mutex_unlock(&session->eh_mutex);
2399 return FAILED;
2400 }
2401
2402 spin_unlock_bh(&session->frwd_lock);
2403 mutex_unlock(&session->eh_mutex);
2404 /*
2405 * we drop the lock here but the leadconn cannot be destoyed while
2406 * we are in the scsi eh
2407 */
2408 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2409
2410 ISCSI_DBG_EH(session, "wait for relogin\n");
2411 wait_event_interruptible(conn->ehwait,
2412 session->state == ISCSI_STATE_TERMINATE ||
2413 session->state == ISCSI_STATE_LOGGED_IN ||
2414 session->state == ISCSI_STATE_RECOVERY_FAILED);
2415 if (signal_pending(current))
2416 flush_signals(current);
2417
2418 mutex_lock(&session->eh_mutex);
2419 spin_lock_bh(&session->frwd_lock);
2420 if (session->state == ISCSI_STATE_LOGGED_IN) {
2421 ISCSI_DBG_EH(session,
2422 "session reset succeeded for %s,%s\n",
2423 session->targetname, conn->persistent_address);
2424 } else
2425 goto failed;
2426 spin_unlock_bh(&session->frwd_lock);
2427 mutex_unlock(&session->eh_mutex);
2428 return SUCCESS;
2429}
2430EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2431
2432static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2433{
2434 memset(hdr, 0, sizeof(*hdr));
2435 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2436 hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2437 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2438 hdr->rtt = RESERVED_ITT;
2439}
2440
2441/**
2442 * iscsi_eh_target_reset - reset target
2443 * @sc: scsi command
2444 *
2445 * This will attempt to send a warm target reset.
2446 */
2447static int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2448{
2449 struct iscsi_cls_session *cls_session;
2450 struct iscsi_session *session;
2451 struct iscsi_conn *conn;
2452 struct iscsi_tm *hdr;
2453 int rc = FAILED;
2454
2455 cls_session = starget_to_session(scsi_target(sc->device));
2456 session = cls_session->dd_data;
2457
2458 ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2459 session->targetname);
2460
2461 mutex_lock(&session->eh_mutex);
2462 spin_lock_bh(&session->frwd_lock);
2463 /*
2464 * Just check if we are not logged in. We cannot check for
2465 * the phase because the reset could come from a ioctl.
2466 */
2467 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2468 goto unlock;
2469 conn = session->leadconn;
2470
2471 /* only have one tmf outstanding at a time */
2472 if (conn->tmf_state != TMF_INITIAL)
2473 goto unlock;
2474 conn->tmf_state = TMF_QUEUED;
2475
2476 hdr = &conn->tmhdr;
2477 iscsi_prep_tgt_reset_pdu(sc, hdr);
2478
2479 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2480 session->tgt_reset_timeout)) {
2481 rc = FAILED;
2482 goto unlock;
2483 }
2484
2485 switch (conn->tmf_state) {
2486 case TMF_SUCCESS:
2487 break;
2488 case TMF_TIMEDOUT:
2489 spin_unlock_bh(&session->frwd_lock);
2490 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2491 goto done;
2492 default:
2493 conn->tmf_state = TMF_INITIAL;
2494 goto unlock;
2495 }
2496
2497 rc = SUCCESS;
2498 spin_unlock_bh(&session->frwd_lock);
2499
2500 iscsi_suspend_tx(conn);
2501
2502 spin_lock_bh(&session->frwd_lock);
2503 memset(hdr, 0, sizeof(*hdr));
2504 fail_scsi_tasks(conn, -1, DID_ERROR);
2505 conn->tmf_state = TMF_INITIAL;
2506 spin_unlock_bh(&session->frwd_lock);
2507
2508 iscsi_start_tx(conn);
2509 goto done;
2510
2511unlock:
2512 spin_unlock_bh(&session->frwd_lock);
2513done:
2514 ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2515 rc == SUCCESS ? "SUCCESS" : "FAILED");
2516 mutex_unlock(&session->eh_mutex);
2517 return rc;
2518}
2519
2520/**
2521 * iscsi_eh_recover_target - reset target and possibly the session
2522 * @sc: scsi command
2523 *
2524 * This will attempt to send a warm target reset. If that fails,
2525 * we will escalate to ERL0 session recovery.
2526 */
2527int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2528{
2529 int rc;
2530
2531 rc = iscsi_eh_target_reset(sc);
2532 if (rc == FAILED)
2533 rc = iscsi_eh_session_reset(sc);
2534 return rc;
2535}
2536EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2537
2538/*
2539 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2540 * should be accessed via kfifo_{get,put} on q->queue.
2541 * Optionally, the caller can obtain the array of object pointers
2542 * by passing in a non-NULL @items pointer
2543 */
2544int
2545iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2546{
2547 int i, num_arrays = 1;
2548
2549 memset(q, 0, sizeof(*q));
2550
2551 q->max = max;
2552
2553 /* If the user passed an items pointer, he wants a copy of
2554 * the array. */
2555 if (items)
2556 num_arrays++;
2557 q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
2558 if (q->pool == NULL)
2559 return -ENOMEM;
2560
2561 kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2562
2563 for (i = 0; i < max; i++) {
2564 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2565 if (q->pool[i] == NULL) {
2566 q->max = i;
2567 goto enomem;
2568 }
2569 kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2570 }
2571
2572 if (items) {
2573 *items = q->pool + max;
2574 memcpy(*items, q->pool, max * sizeof(void *));
2575 }
2576
2577 return 0;
2578
2579enomem:
2580 iscsi_pool_free(q);
2581 return -ENOMEM;
2582}
2583EXPORT_SYMBOL_GPL(iscsi_pool_init);
2584
2585void iscsi_pool_free(struct iscsi_pool *q)
2586{
2587 int i;
2588
2589 for (i = 0; i < q->max; i++)
2590 kfree(q->pool[i]);
2591 kfree(q->pool);
2592}
2593EXPORT_SYMBOL_GPL(iscsi_pool_free);
2594
2595/**
2596 * iscsi_host_add - add host to system
2597 * @shost: scsi host
2598 * @pdev: parent device
2599 *
2600 * This should be called by partial offload and software iscsi drivers
2601 * to add a host to the system.
2602 */
2603int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2604{
2605 if (!shost->can_queue)
2606 shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2607
2608 if (!shost->cmd_per_lun)
2609 shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2610
2611 if (!shost->transportt->eh_timed_out)
2612 shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
2613 return scsi_add_host(shost, pdev);
2614}
2615EXPORT_SYMBOL_GPL(iscsi_host_add);
2616
2617/**
2618 * iscsi_host_alloc - allocate a host and driver data
2619 * @sht: scsi host template
2620 * @dd_data_size: driver host data size
2621 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2622 *
2623 * This should be called by partial offload and software iscsi drivers.
2624 * To access the driver specific memory use the iscsi_host_priv() macro.
2625 */
2626struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2627 int dd_data_size, bool xmit_can_sleep)
2628{
2629 struct Scsi_Host *shost;
2630 struct iscsi_host *ihost;
2631
2632 shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2633 if (!shost)
2634 return NULL;
2635 ihost = shost_priv(shost);
2636
2637 if (xmit_can_sleep) {
2638 snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2639 "iscsi_q_%d", shost->host_no);
2640 ihost->workq = create_singlethread_workqueue(ihost->workq_name);
2641 if (!ihost->workq)
2642 goto free_host;
2643 }
2644
2645 spin_lock_init(&ihost->lock);
2646 ihost->state = ISCSI_HOST_SETUP;
2647 ihost->num_sessions = 0;
2648 init_waitqueue_head(&ihost->session_removal_wq);
2649 return shost;
2650
2651free_host:
2652 scsi_host_put(shost);
2653 return NULL;
2654}
2655EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2656
2657static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2658{
2659 iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2660}
2661
2662/**
2663 * iscsi_host_remove - remove host and sessions
2664 * @shost: scsi host
2665 *
2666 * If there are any sessions left, this will initiate the removal and wait
2667 * for the completion.
2668 */
2669void iscsi_host_remove(struct Scsi_Host *shost)
2670{
2671 struct iscsi_host *ihost = shost_priv(shost);
2672 unsigned long flags;
2673
2674 spin_lock_irqsave(&ihost->lock, flags);
2675 ihost->state = ISCSI_HOST_REMOVED;
2676 spin_unlock_irqrestore(&ihost->lock, flags);
2677
2678 iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2679 wait_event_interruptible(ihost->session_removal_wq,
2680 ihost->num_sessions == 0);
2681 if (signal_pending(current))
2682 flush_signals(current);
2683
2684 scsi_remove_host(shost);
2685 if (ihost->workq)
2686 destroy_workqueue(ihost->workq);
2687}
2688EXPORT_SYMBOL_GPL(iscsi_host_remove);
2689
2690void iscsi_host_free(struct Scsi_Host *shost)
2691{
2692 struct iscsi_host *ihost = shost_priv(shost);
2693
2694 kfree(ihost->netdev);
2695 kfree(ihost->hwaddress);
2696 kfree(ihost->initiatorname);
2697 scsi_host_put(shost);
2698}
2699EXPORT_SYMBOL_GPL(iscsi_host_free);
2700
2701static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2702{
2703 struct iscsi_host *ihost = shost_priv(shost);
2704 unsigned long flags;
2705
2706 shost = scsi_host_get(shost);
2707 if (!shost) {
2708 printk(KERN_ERR "Invalid state. Cannot notify host removal "
2709 "of session teardown event because host already "
2710 "removed.\n");
2711 return;
2712 }
2713
2714 spin_lock_irqsave(&ihost->lock, flags);
2715 ihost->num_sessions--;
2716 if (ihost->num_sessions == 0)
2717 wake_up(&ihost->session_removal_wq);
2718 spin_unlock_irqrestore(&ihost->lock, flags);
2719 scsi_host_put(shost);
2720}
2721
2722/**
2723 * iscsi_session_setup - create iscsi cls session and host and session
2724 * @iscsit: iscsi transport template
2725 * @shost: scsi host
2726 * @cmds_max: session can queue
2727 * @cmd_task_size: LLD task private data size
2728 * @initial_cmdsn: initial CmdSN
2729 *
2730 * This can be used by software iscsi_transports that allocate
2731 * a session per scsi host.
2732 *
2733 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2734 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2735 * for nop handling and login/logout requests.
2736 */
2737struct iscsi_cls_session *
2738iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2739 uint16_t cmds_max, int dd_size, int cmd_task_size,
2740 uint32_t initial_cmdsn, unsigned int id)
2741{
2742 struct iscsi_host *ihost = shost_priv(shost);
2743 struct iscsi_session *session;
2744 struct iscsi_cls_session *cls_session;
2745 int cmd_i, scsi_cmds, total_cmds = cmds_max;
2746 unsigned long flags;
2747
2748 spin_lock_irqsave(&ihost->lock, flags);
2749 if (ihost->state == ISCSI_HOST_REMOVED) {
2750 spin_unlock_irqrestore(&ihost->lock, flags);
2751 return NULL;
2752 }
2753 ihost->num_sessions++;
2754 spin_unlock_irqrestore(&ihost->lock, flags);
2755
2756 if (!total_cmds)
2757 total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2758 /*
2759 * The iscsi layer needs some tasks for nop handling and tmfs,
2760 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2761 * + 1 command for scsi IO.
2762 */
2763 if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2764 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2765 "must be a power of two that is at least %d.\n",
2766 total_cmds, ISCSI_TOTAL_CMDS_MIN);
2767 goto dec_session_count;
2768 }
2769
2770 if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2771 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2772 "must be a power of 2 less than or equal to %d.\n",
2773 cmds_max, ISCSI_TOTAL_CMDS_MAX);
2774 total_cmds = ISCSI_TOTAL_CMDS_MAX;
2775 }
2776
2777 if (!is_power_of_2(total_cmds)) {
2778 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2779 "must be a power of 2.\n", total_cmds);
2780 total_cmds = rounddown_pow_of_two(total_cmds);
2781 if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
2782 return NULL;
2783 printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
2784 total_cmds);
2785 }
2786 scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2787
2788 cls_session = iscsi_alloc_session(shost, iscsit,
2789 sizeof(struct iscsi_session) +
2790 dd_size);
2791 if (!cls_session)
2792 goto dec_session_count;
2793 session = cls_session->dd_data;
2794 session->cls_session = cls_session;
2795 session->host = shost;
2796 session->state = ISCSI_STATE_FREE;
2797 session->fast_abort = 1;
2798 session->tgt_reset_timeout = 30;
2799 session->lu_reset_timeout = 15;
2800 session->abort_timeout = 10;
2801 session->scsi_cmds_max = scsi_cmds;
2802 session->cmds_max = total_cmds;
2803 session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2804 session->exp_cmdsn = initial_cmdsn + 1;
2805 session->max_cmdsn = initial_cmdsn + 1;
2806 session->max_r2t = 1;
2807 session->tt = iscsit;
2808 session->dd_data = cls_session->dd_data + sizeof(*session);
2809
2810 mutex_init(&session->eh_mutex);
2811 spin_lock_init(&session->frwd_lock);
2812 spin_lock_init(&session->back_lock);
2813
2814 /* initialize SCSI PDU commands pool */
2815 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2816 (void***)&session->cmds,
2817 cmd_task_size + sizeof(struct iscsi_task)))
2818 goto cmdpool_alloc_fail;
2819
2820 /* pre-format cmds pool with ITT */
2821 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2822 struct iscsi_task *task = session->cmds[cmd_i];
2823
2824 if (cmd_task_size)
2825 task->dd_data = &task[1];
2826 task->itt = cmd_i;
2827 task->state = ISCSI_TASK_FREE;
2828 INIT_LIST_HEAD(&task->running);
2829 }
2830
2831 if (!try_module_get(iscsit->owner))
2832 goto module_get_fail;
2833
2834 if (iscsi_add_session(cls_session, id))
2835 goto cls_session_fail;
2836
2837 return cls_session;
2838
2839cls_session_fail:
2840 module_put(iscsit->owner);
2841module_get_fail:
2842 iscsi_pool_free(&session->cmdpool);
2843cmdpool_alloc_fail:
2844 iscsi_free_session(cls_session);
2845dec_session_count:
2846 iscsi_host_dec_session_cnt(shost);
2847 return NULL;
2848}
2849EXPORT_SYMBOL_GPL(iscsi_session_setup);
2850
2851/**
2852 * iscsi_session_teardown - destroy session, host, and cls_session
2853 * @cls_session: iscsi session
2854 *
2855 * The driver must have called iscsi_remove_session before
2856 * calling this.
2857 */
2858void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2859{
2860 struct iscsi_session *session = cls_session->dd_data;
2861 struct module *owner = cls_session->transport->owner;
2862 struct Scsi_Host *shost = session->host;
2863
2864 iscsi_pool_free(&session->cmdpool);
2865
2866 kfree(session->password);
2867 kfree(session->password_in);
2868 kfree(session->username);
2869 kfree(session->username_in);
2870 kfree(session->targetname);
2871 kfree(session->targetalias);
2872 kfree(session->initiatorname);
2873 kfree(session->boot_root);
2874 kfree(session->boot_nic);
2875 kfree(session->boot_target);
2876 kfree(session->ifacename);
2877 kfree(session->portal_type);
2878 kfree(session->discovery_parent_type);
2879
2880 iscsi_destroy_session(cls_session);
2881 iscsi_host_dec_session_cnt(shost);
2882 module_put(owner);
2883}
2884EXPORT_SYMBOL_GPL(iscsi_session_teardown);
2885
2886/**
2887 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
2888 * @cls_session: iscsi_cls_session
2889 * @dd_size: private driver data size
2890 * @conn_idx: cid
2891 */
2892struct iscsi_cls_conn *
2893iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2894 uint32_t conn_idx)
2895{
2896 struct iscsi_session *session = cls_session->dd_data;
2897 struct iscsi_conn *conn;
2898 struct iscsi_cls_conn *cls_conn;
2899 char *data;
2900
2901 cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2902 conn_idx);
2903 if (!cls_conn)
2904 return NULL;
2905 conn = cls_conn->dd_data;
2906 memset(conn, 0, sizeof(*conn) + dd_size);
2907
2908 conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2909 conn->session = session;
2910 conn->cls_conn = cls_conn;
2911 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2912 conn->id = conn_idx;
2913 conn->exp_statsn = 0;
2914 conn->tmf_state = TMF_INITIAL;
2915
2916 init_timer(&conn->transport_timer);
2917 conn->transport_timer.data = (unsigned long)conn;
2918 conn->transport_timer.function = iscsi_check_transport_timeouts;
2919
2920 INIT_LIST_HEAD(&conn->mgmtqueue);
2921 INIT_LIST_HEAD(&conn->cmdqueue);
2922 INIT_LIST_HEAD(&conn->requeue);
2923 spin_lock_init(&conn->taskqueuelock);
2924 INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2925
2926 /* allocate login_task used for the login/text sequences */
2927 spin_lock_bh(&session->frwd_lock);
2928 if (!kfifo_out(&session->cmdpool.queue,
2929 (void*)&conn->login_task,
2930 sizeof(void*))) {
2931 spin_unlock_bh(&session->frwd_lock);
2932 goto login_task_alloc_fail;
2933 }
2934 spin_unlock_bh(&session->frwd_lock);
2935
2936 data = (char *) __get_free_pages(GFP_KERNEL,
2937 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2938 if (!data)
2939 goto login_task_data_alloc_fail;
2940 conn->login_task->data = conn->data = data;
2941
2942 init_timer(&conn->tmf_timer);
2943 init_waitqueue_head(&conn->ehwait);
2944
2945 return cls_conn;
2946
2947login_task_data_alloc_fail:
2948 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2949 sizeof(void*));
2950login_task_alloc_fail:
2951 iscsi_destroy_conn(cls_conn);
2952 return NULL;
2953}
2954EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2955
2956/**
2957 * iscsi_conn_teardown - teardown iscsi connection
2958 * cls_conn: iscsi class connection
2959 *
2960 * TODO: we may need to make this into a two step process
2961 * like scsi-mls remove + put host
2962 */
2963void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2964{
2965 struct iscsi_conn *conn = cls_conn->dd_data;
2966 struct iscsi_session *session = conn->session;
2967
2968 del_timer_sync(&conn->transport_timer);
2969
2970 mutex_lock(&session->eh_mutex);
2971 spin_lock_bh(&session->frwd_lock);
2972 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2973 if (session->leadconn == conn) {
2974 /*
2975 * leading connection? then give up on recovery.
2976 */
2977 session->state = ISCSI_STATE_TERMINATE;
2978 wake_up(&conn->ehwait);
2979 }
2980 spin_unlock_bh(&session->frwd_lock);
2981
2982 /* flush queued up work because we free the connection below */
2983 iscsi_suspend_tx(conn);
2984
2985 spin_lock_bh(&session->frwd_lock);
2986 free_pages((unsigned long) conn->data,
2987 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2988 kfree(conn->persistent_address);
2989 kfree(conn->local_ipaddr);
2990 /* regular RX path uses back_lock */
2991 spin_lock_bh(&session->back_lock);
2992 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2993 sizeof(void*));
2994 spin_unlock_bh(&session->back_lock);
2995 if (session->leadconn == conn)
2996 session->leadconn = NULL;
2997 spin_unlock_bh(&session->frwd_lock);
2998 mutex_unlock(&session->eh_mutex);
2999
3000 iscsi_destroy_conn(cls_conn);
3001}
3002EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
3003
3004int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
3005{
3006 struct iscsi_conn *conn = cls_conn->dd_data;
3007 struct iscsi_session *session = conn->session;
3008
3009 if (!session) {
3010 iscsi_conn_printk(KERN_ERR, conn,
3011 "can't start unbound connection\n");
3012 return -EPERM;
3013 }
3014
3015 if ((session->imm_data_en || !session->initial_r2t_en) &&
3016 session->first_burst > session->max_burst) {
3017 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
3018 "first_burst %d max_burst %d\n",
3019 session->first_burst, session->max_burst);
3020 return -EINVAL;
3021 }
3022
3023 if (conn->ping_timeout && !conn->recv_timeout) {
3024 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
3025 "zero. Using 5 seconds\n.");
3026 conn->recv_timeout = 5;
3027 }
3028
3029 if (conn->recv_timeout && !conn->ping_timeout) {
3030 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
3031 "zero. Using 5 seconds.\n");
3032 conn->ping_timeout = 5;
3033 }
3034
3035 spin_lock_bh(&session->frwd_lock);
3036 conn->c_stage = ISCSI_CONN_STARTED;
3037 session->state = ISCSI_STATE_LOGGED_IN;
3038 session->queued_cmdsn = session->cmdsn;
3039
3040 conn->last_recv = jiffies;
3041 conn->last_ping = jiffies;
3042 if (conn->recv_timeout && conn->ping_timeout)
3043 mod_timer(&conn->transport_timer,
3044 jiffies + (conn->recv_timeout * HZ));
3045
3046 switch(conn->stop_stage) {
3047 case STOP_CONN_RECOVER:
3048 /*
3049 * unblock eh_abort() if it is blocked. re-try all
3050 * commands after successful recovery
3051 */
3052 conn->stop_stage = 0;
3053 conn->tmf_state = TMF_INITIAL;
3054 session->age++;
3055 if (session->age == 16)
3056 session->age = 0;
3057 break;
3058 case STOP_CONN_TERM:
3059 conn->stop_stage = 0;
3060 break;
3061 default:
3062 break;
3063 }
3064 spin_unlock_bh(&session->frwd_lock);
3065
3066 iscsi_unblock_session(session->cls_session);
3067 wake_up(&conn->ehwait);
3068 return 0;
3069}
3070EXPORT_SYMBOL_GPL(iscsi_conn_start);
3071
3072static void
3073fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3074{
3075 struct iscsi_task *task;
3076 int i, state;
3077
3078 for (i = 0; i < conn->session->cmds_max; i++) {
3079 task = conn->session->cmds[i];
3080 if (task->sc)
3081 continue;
3082
3083 if (task->state == ISCSI_TASK_FREE)
3084 continue;
3085
3086 ISCSI_DBG_SESSION(conn->session,
3087 "failing mgmt itt 0x%x state %d\n",
3088 task->itt, task->state);
3089 state = ISCSI_TASK_ABRT_SESS_RECOV;
3090 if (task->state == ISCSI_TASK_PENDING)
3091 state = ISCSI_TASK_COMPLETED;
3092 iscsi_complete_task(task, state);
3093
3094 }
3095}
3096
3097static void iscsi_start_session_recovery(struct iscsi_session *session,
3098 struct iscsi_conn *conn, int flag)
3099{
3100 int old_stop_stage;
3101
3102 mutex_lock(&session->eh_mutex);
3103 spin_lock_bh(&session->frwd_lock);
3104 if (conn->stop_stage == STOP_CONN_TERM) {
3105 spin_unlock_bh(&session->frwd_lock);
3106 mutex_unlock(&session->eh_mutex);
3107 return;
3108 }
3109
3110 /*
3111 * When this is called for the in_login state, we only want to clean
3112 * up the login task and connection. We do not need to block and set
3113 * the recovery state again
3114 */
3115 if (flag == STOP_CONN_TERM)
3116 session->state = ISCSI_STATE_TERMINATE;
3117 else if (conn->stop_stage != STOP_CONN_RECOVER)
3118 session->state = ISCSI_STATE_IN_RECOVERY;
3119
3120 old_stop_stage = conn->stop_stage;
3121 conn->stop_stage = flag;
3122 spin_unlock_bh(&session->frwd_lock);
3123
3124 del_timer_sync(&conn->transport_timer);
3125 iscsi_suspend_tx(conn);
3126
3127 spin_lock_bh(&session->frwd_lock);
3128 conn->c_stage = ISCSI_CONN_STOPPED;
3129 spin_unlock_bh(&session->frwd_lock);
3130
3131 /*
3132 * for connection level recovery we should not calculate
3133 * header digest. conn->hdr_size used for optimization
3134 * in hdr_extract() and will be re-negotiated at
3135 * set_param() time.
3136 */
3137 if (flag == STOP_CONN_RECOVER) {
3138 conn->hdrdgst_en = 0;
3139 conn->datadgst_en = 0;
3140 if (session->state == ISCSI_STATE_IN_RECOVERY &&
3141 old_stop_stage != STOP_CONN_RECOVER) {
3142 ISCSI_DBG_SESSION(session, "blocking session\n");
3143 iscsi_block_session(session->cls_session);
3144 }
3145 }
3146
3147 /*
3148 * flush queues.
3149 */
3150 spin_lock_bh(&session->frwd_lock);
3151 fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3152 fail_mgmt_tasks(session, conn);
3153 memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
3154 spin_unlock_bh(&session->frwd_lock);
3155 mutex_unlock(&session->eh_mutex);
3156}
3157
3158void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3159{
3160 struct iscsi_conn *conn = cls_conn->dd_data;
3161 struct iscsi_session *session = conn->session;
3162
3163 switch (flag) {
3164 case STOP_CONN_RECOVER:
3165 case STOP_CONN_TERM:
3166 iscsi_start_session_recovery(session, conn, flag);
3167 break;
3168 default:
3169 iscsi_conn_printk(KERN_ERR, conn,
3170 "invalid stop flag %d\n", flag);
3171 }
3172}
3173EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3174
3175int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3176 struct iscsi_cls_conn *cls_conn, int is_leading)
3177{
3178 struct iscsi_session *session = cls_session->dd_data;
3179 struct iscsi_conn *conn = cls_conn->dd_data;
3180
3181 spin_lock_bh(&session->frwd_lock);
3182 if (is_leading)
3183 session->leadconn = conn;
3184 spin_unlock_bh(&session->frwd_lock);
3185
3186 /*
3187 * Unblock xmitworker(), Login Phase will pass through.
3188 */
3189 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3190 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3191 return 0;
3192}
3193EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3194
3195int iscsi_switch_str_param(char **param, char *new_val_buf)
3196{
3197 char *new_val;
3198
3199 if (*param) {
3200 if (!strcmp(*param, new_val_buf))
3201 return 0;
3202 }
3203
3204 new_val = kstrdup(new_val_buf, GFP_NOIO);
3205 if (!new_val)
3206 return -ENOMEM;
3207
3208 kfree(*param);
3209 *param = new_val;
3210 return 0;
3211}
3212EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3213
3214int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3215 enum iscsi_param param, char *buf, int buflen)
3216{
3217 struct iscsi_conn *conn = cls_conn->dd_data;
3218 struct iscsi_session *session = conn->session;
3219 int val;
3220
3221 switch(param) {
3222 case ISCSI_PARAM_FAST_ABORT:
3223 sscanf(buf, "%d", &session->fast_abort);
3224 break;
3225 case ISCSI_PARAM_ABORT_TMO:
3226 sscanf(buf, "%d", &session->abort_timeout);
3227 break;
3228 case ISCSI_PARAM_LU_RESET_TMO:
3229 sscanf(buf, "%d", &session->lu_reset_timeout);
3230 break;
3231 case ISCSI_PARAM_TGT_RESET_TMO:
3232 sscanf(buf, "%d", &session->tgt_reset_timeout);
3233 break;
3234 case ISCSI_PARAM_PING_TMO:
3235 sscanf(buf, "%d", &conn->ping_timeout);
3236 break;
3237 case ISCSI_PARAM_RECV_TMO:
3238 sscanf(buf, "%d", &conn->recv_timeout);
3239 break;
3240 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3241 sscanf(buf, "%d", &conn->max_recv_dlength);
3242 break;
3243 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3244 sscanf(buf, "%d", &conn->max_xmit_dlength);
3245 break;
3246 case ISCSI_PARAM_HDRDGST_EN:
3247 sscanf(buf, "%d", &conn->hdrdgst_en);
3248 break;
3249 case ISCSI_PARAM_DATADGST_EN:
3250 sscanf(buf, "%d", &conn->datadgst_en);
3251 break;
3252 case ISCSI_PARAM_INITIAL_R2T_EN:
3253 sscanf(buf, "%d", &session->initial_r2t_en);
3254 break;
3255 case ISCSI_PARAM_MAX_R2T:
3256 sscanf(buf, "%hu", &session->max_r2t);
3257 break;
3258 case ISCSI_PARAM_IMM_DATA_EN:
3259 sscanf(buf, "%d", &session->imm_data_en);
3260 break;
3261 case ISCSI_PARAM_FIRST_BURST:
3262 sscanf(buf, "%d", &session->first_burst);
3263 break;
3264 case ISCSI_PARAM_MAX_BURST:
3265 sscanf(buf, "%d", &session->max_burst);
3266 break;
3267 case ISCSI_PARAM_PDU_INORDER_EN:
3268 sscanf(buf, "%d", &session->pdu_inorder_en);
3269 break;
3270 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3271 sscanf(buf, "%d", &session->dataseq_inorder_en);
3272 break;
3273 case ISCSI_PARAM_ERL:
3274 sscanf(buf, "%d", &session->erl);
3275 break;
3276 case ISCSI_PARAM_EXP_STATSN:
3277 sscanf(buf, "%u", &conn->exp_statsn);
3278 break;
3279 case ISCSI_PARAM_USERNAME:
3280 return iscsi_switch_str_param(&session->username, buf);
3281 case ISCSI_PARAM_USERNAME_IN:
3282 return iscsi_switch_str_param(&session->username_in, buf);
3283 case ISCSI_PARAM_PASSWORD:
3284 return iscsi_switch_str_param(&session->password, buf);
3285 case ISCSI_PARAM_PASSWORD_IN:
3286 return iscsi_switch_str_param(&session->password_in, buf);
3287 case ISCSI_PARAM_TARGET_NAME:
3288 return iscsi_switch_str_param(&session->targetname, buf);
3289 case ISCSI_PARAM_TARGET_ALIAS:
3290 return iscsi_switch_str_param(&session->targetalias, buf);
3291 case ISCSI_PARAM_TPGT:
3292 sscanf(buf, "%d", &session->tpgt);
3293 break;
3294 case ISCSI_PARAM_PERSISTENT_PORT:
3295 sscanf(buf, "%d", &conn->persistent_port);
3296 break;
3297 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3298 return iscsi_switch_str_param(&conn->persistent_address, buf);
3299 case ISCSI_PARAM_IFACE_NAME:
3300 return iscsi_switch_str_param(&session->ifacename, buf);
3301 case ISCSI_PARAM_INITIATOR_NAME:
3302 return iscsi_switch_str_param(&session->initiatorname, buf);
3303 case ISCSI_PARAM_BOOT_ROOT:
3304 return iscsi_switch_str_param(&session->boot_root, buf);
3305 case ISCSI_PARAM_BOOT_NIC:
3306 return iscsi_switch_str_param(&session->boot_nic, buf);
3307 case ISCSI_PARAM_BOOT_TARGET:
3308 return iscsi_switch_str_param(&session->boot_target, buf);
3309 case ISCSI_PARAM_PORTAL_TYPE:
3310 return iscsi_switch_str_param(&session->portal_type, buf);
3311 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3312 return iscsi_switch_str_param(&session->discovery_parent_type,
3313 buf);
3314 case ISCSI_PARAM_DISCOVERY_SESS:
3315 sscanf(buf, "%d", &val);
3316 session->discovery_sess = !!val;
3317 break;
3318 case ISCSI_PARAM_LOCAL_IPADDR:
3319 return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3320 default:
3321 return -ENOSYS;
3322 }
3323
3324 return 0;
3325}
3326EXPORT_SYMBOL_GPL(iscsi_set_param);
3327
3328int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3329 enum iscsi_param param, char *buf)
3330{
3331 struct iscsi_session *session = cls_session->dd_data;
3332 int len;
3333
3334 switch(param) {
3335 case ISCSI_PARAM_FAST_ABORT:
3336 len = sprintf(buf, "%d\n", session->fast_abort);
3337 break;
3338 case ISCSI_PARAM_ABORT_TMO:
3339 len = sprintf(buf, "%d\n", session->abort_timeout);
3340 break;
3341 case ISCSI_PARAM_LU_RESET_TMO:
3342 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
3343 break;
3344 case ISCSI_PARAM_TGT_RESET_TMO:
3345 len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
3346 break;
3347 case ISCSI_PARAM_INITIAL_R2T_EN:
3348 len = sprintf(buf, "%d\n", session->initial_r2t_en);
3349 break;
3350 case ISCSI_PARAM_MAX_R2T:
3351 len = sprintf(buf, "%hu\n", session->max_r2t);
3352 break;
3353 case ISCSI_PARAM_IMM_DATA_EN:
3354 len = sprintf(buf, "%d\n", session->imm_data_en);
3355 break;
3356 case ISCSI_PARAM_FIRST_BURST:
3357 len = sprintf(buf, "%u\n", session->first_burst);
3358 break;
3359 case ISCSI_PARAM_MAX_BURST:
3360 len = sprintf(buf, "%u\n", session->max_burst);
3361 break;
3362 case ISCSI_PARAM_PDU_INORDER_EN:
3363 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
3364 break;
3365 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3366 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
3367 break;
3368 case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3369 len = sprintf(buf, "%d\n", session->def_taskmgmt_tmo);
3370 break;
3371 case ISCSI_PARAM_ERL:
3372 len = sprintf(buf, "%d\n", session->erl);
3373 break;
3374 case ISCSI_PARAM_TARGET_NAME:
3375 len = sprintf(buf, "%s\n", session->targetname);
3376 break;
3377 case ISCSI_PARAM_TARGET_ALIAS:
3378 len = sprintf(buf, "%s\n", session->targetalias);
3379 break;
3380 case ISCSI_PARAM_TPGT:
3381 len = sprintf(buf, "%d\n", session->tpgt);
3382 break;
3383 case ISCSI_PARAM_USERNAME:
3384 len = sprintf(buf, "%s\n", session->username);
3385 break;
3386 case ISCSI_PARAM_USERNAME_IN:
3387 len = sprintf(buf, "%s\n", session->username_in);
3388 break;
3389 case ISCSI_PARAM_PASSWORD:
3390 len = sprintf(buf, "%s\n", session->password);
3391 break;
3392 case ISCSI_PARAM_PASSWORD_IN:
3393 len = sprintf(buf, "%s\n", session->password_in);
3394 break;
3395 case ISCSI_PARAM_IFACE_NAME:
3396 len = sprintf(buf, "%s\n", session->ifacename);
3397 break;
3398 case ISCSI_PARAM_INITIATOR_NAME:
3399 len = sprintf(buf, "%s\n", session->initiatorname);
3400 break;
3401 case ISCSI_PARAM_BOOT_ROOT:
3402 len = sprintf(buf, "%s\n", session->boot_root);
3403 break;
3404 case ISCSI_PARAM_BOOT_NIC:
3405 len = sprintf(buf, "%s\n", session->boot_nic);
3406 break;
3407 case ISCSI_PARAM_BOOT_TARGET:
3408 len = sprintf(buf, "%s\n", session->boot_target);
3409 break;
3410 case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3411 len = sprintf(buf, "%u\n", session->auto_snd_tgt_disable);
3412 break;
3413 case ISCSI_PARAM_DISCOVERY_SESS:
3414 len = sprintf(buf, "%u\n", session->discovery_sess);
3415 break;
3416 case ISCSI_PARAM_PORTAL_TYPE:
3417 len = sprintf(buf, "%s\n", session->portal_type);
3418 break;
3419 case ISCSI_PARAM_CHAP_AUTH_EN:
3420 len = sprintf(buf, "%u\n", session->chap_auth_en);
3421 break;
3422 case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3423 len = sprintf(buf, "%u\n", session->discovery_logout_en);
3424 break;
3425 case ISCSI_PARAM_BIDI_CHAP_EN:
3426 len = sprintf(buf, "%u\n", session->bidi_chap_en);
3427 break;
3428 case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3429 len = sprintf(buf, "%u\n", session->discovery_auth_optional);
3430 break;
3431 case ISCSI_PARAM_DEF_TIME2WAIT:
3432 len = sprintf(buf, "%d\n", session->time2wait);
3433 break;
3434 case ISCSI_PARAM_DEF_TIME2RETAIN:
3435 len = sprintf(buf, "%d\n", session->time2retain);
3436 break;
3437 case ISCSI_PARAM_TSID:
3438 len = sprintf(buf, "%u\n", session->tsid);
3439 break;
3440 case ISCSI_PARAM_ISID:
3441 len = sprintf(buf, "%02x%02x%02x%02x%02x%02x\n",
3442 session->isid[0], session->isid[1],
3443 session->isid[2], session->isid[3],
3444 session->isid[4], session->isid[5]);
3445 break;
3446 case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3447 len = sprintf(buf, "%u\n", session->discovery_parent_idx);
3448 break;
3449 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3450 if (session->discovery_parent_type)
3451 len = sprintf(buf, "%s\n",
3452 session->discovery_parent_type);
3453 else
3454 len = sprintf(buf, "\n");
3455 break;
3456 default:
3457 return -ENOSYS;
3458 }
3459
3460 return len;
3461}
3462EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3463
3464int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3465 enum iscsi_param param, char *buf)
3466{
3467 struct sockaddr_in6 *sin6 = NULL;
3468 struct sockaddr_in *sin = NULL;
3469 int len;
3470
3471 switch (addr->ss_family) {
3472 case AF_INET:
3473 sin = (struct sockaddr_in *)addr;
3474 break;
3475 case AF_INET6:
3476 sin6 = (struct sockaddr_in6 *)addr;
3477 break;
3478 default:
3479 return -EINVAL;
3480 }
3481
3482 switch (param) {
3483 case ISCSI_PARAM_CONN_ADDRESS:
3484 case ISCSI_HOST_PARAM_IPADDRESS:
3485 if (sin)
3486 len = sprintf(buf, "%pI4\n", &sin->sin_addr.s_addr);
3487 else
3488 len = sprintf(buf, "%pI6\n", &sin6->sin6_addr);
3489 break;
3490 case ISCSI_PARAM_CONN_PORT:
3491 case ISCSI_PARAM_LOCAL_PORT:
3492 if (sin)
3493 len = sprintf(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3494 else
3495 len = sprintf(buf, "%hu\n",
3496 be16_to_cpu(sin6->sin6_port));
3497 break;
3498 default:
3499 return -EINVAL;
3500 }
3501
3502 return len;
3503}
3504EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3505
3506int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3507 enum iscsi_param param, char *buf)
3508{
3509 struct iscsi_conn *conn = cls_conn->dd_data;
3510 int len;
3511
3512 switch(param) {
3513 case ISCSI_PARAM_PING_TMO:
3514 len = sprintf(buf, "%u\n", conn->ping_timeout);
3515 break;
3516 case ISCSI_PARAM_RECV_TMO:
3517 len = sprintf(buf, "%u\n", conn->recv_timeout);
3518 break;
3519 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3520 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
3521 break;
3522 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3523 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
3524 break;
3525 case ISCSI_PARAM_HDRDGST_EN:
3526 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
3527 break;
3528 case ISCSI_PARAM_DATADGST_EN:
3529 len = sprintf(buf, "%d\n", conn->datadgst_en);
3530 break;
3531 case ISCSI_PARAM_IFMARKER_EN:
3532 len = sprintf(buf, "%d\n", conn->ifmarker_en);
3533 break;
3534 case ISCSI_PARAM_OFMARKER_EN:
3535 len = sprintf(buf, "%d\n", conn->ofmarker_en);
3536 break;
3537 case ISCSI_PARAM_EXP_STATSN:
3538 len = sprintf(buf, "%u\n", conn->exp_statsn);
3539 break;
3540 case ISCSI_PARAM_PERSISTENT_PORT:
3541 len = sprintf(buf, "%d\n", conn->persistent_port);
3542 break;
3543 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3544 len = sprintf(buf, "%s\n", conn->persistent_address);
3545 break;
3546 case ISCSI_PARAM_STATSN:
3547 len = sprintf(buf, "%u\n", conn->statsn);
3548 break;
3549 case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3550 len = sprintf(buf, "%u\n", conn->max_segment_size);
3551 break;
3552 case ISCSI_PARAM_KEEPALIVE_TMO:
3553 len = sprintf(buf, "%u\n", conn->keepalive_tmo);
3554 break;
3555 case ISCSI_PARAM_LOCAL_PORT:
3556 len = sprintf(buf, "%u\n", conn->local_port);
3557 break;
3558 case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3559 len = sprintf(buf, "%u\n", conn->tcp_timestamp_stat);
3560 break;
3561 case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3562 len = sprintf(buf, "%u\n", conn->tcp_nagle_disable);
3563 break;
3564 case ISCSI_PARAM_TCP_WSF_DISABLE:
3565 len = sprintf(buf, "%u\n", conn->tcp_wsf_disable);
3566 break;
3567 case ISCSI_PARAM_TCP_TIMER_SCALE:
3568 len = sprintf(buf, "%u\n", conn->tcp_timer_scale);
3569 break;
3570 case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3571 len = sprintf(buf, "%u\n", conn->tcp_timestamp_en);
3572 break;
3573 case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3574 len = sprintf(buf, "%u\n", conn->fragment_disable);
3575 break;
3576 case ISCSI_PARAM_IPV4_TOS:
3577 len = sprintf(buf, "%u\n", conn->ipv4_tos);
3578 break;
3579 case ISCSI_PARAM_IPV6_TC:
3580 len = sprintf(buf, "%u\n", conn->ipv6_traffic_class);
3581 break;
3582 case ISCSI_PARAM_IPV6_FLOW_LABEL:
3583 len = sprintf(buf, "%u\n", conn->ipv6_flow_label);
3584 break;
3585 case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3586 len = sprintf(buf, "%u\n", conn->is_fw_assigned_ipv6);
3587 break;
3588 case ISCSI_PARAM_TCP_XMIT_WSF:
3589 len = sprintf(buf, "%u\n", conn->tcp_xmit_wsf);
3590 break;
3591 case ISCSI_PARAM_TCP_RECV_WSF:
3592 len = sprintf(buf, "%u\n", conn->tcp_recv_wsf);
3593 break;
3594 case ISCSI_PARAM_LOCAL_IPADDR:
3595 len = sprintf(buf, "%s\n", conn->local_ipaddr);
3596 break;
3597 default:
3598 return -ENOSYS;
3599 }
3600
3601 return len;
3602}
3603EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3604
3605int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3606 char *buf)
3607{
3608 struct iscsi_host *ihost = shost_priv(shost);
3609 int len;
3610
3611 switch (param) {
3612 case ISCSI_HOST_PARAM_NETDEV_NAME:
3613 len = sprintf(buf, "%s\n", ihost->netdev);
3614 break;
3615 case ISCSI_HOST_PARAM_HWADDRESS:
3616 len = sprintf(buf, "%s\n", ihost->hwaddress);
3617 break;
3618 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3619 len = sprintf(buf, "%s\n", ihost->initiatorname);
3620 break;
3621 default:
3622 return -ENOSYS;
3623 }
3624
3625 return len;
3626}
3627EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3628
3629int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3630 char *buf, int buflen)
3631{
3632 struct iscsi_host *ihost = shost_priv(shost);
3633
3634 switch (param) {
3635 case ISCSI_HOST_PARAM_NETDEV_NAME:
3636 return iscsi_switch_str_param(&ihost->netdev, buf);
3637 case ISCSI_HOST_PARAM_HWADDRESS:
3638 return iscsi_switch_str_param(&ihost->hwaddress, buf);
3639 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3640 return iscsi_switch_str_param(&ihost->initiatorname, buf);
3641 default:
3642 return -ENOSYS;
3643 }
3644
3645 return 0;
3646}
3647EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3648
3649MODULE_AUTHOR("Mike Christie");
3650MODULE_DESCRIPTION("iSCSI library functions");
3651MODULE_LICENSE("GPL");