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