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lib/string_helpers.c:string_get_size(): use 32 bit arithmetic when possible
[linux-2.6/btrfs-unstable.git] / drivers / scsi / libiscsi.c
blob8053f24f03499335112721cd50c2816da40393a6
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
43 static int iscsi_dbg_lib_conn;
44 module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
45 S_IRUGO | S_IWUSR);
46 MODULE_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
50 static int iscsi_dbg_lib_session;
51 module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
52 S_IRUGO | S_IWUSR);
53 MODULE_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
57 static int iscsi_dbg_lib_eh;
58 module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
59 S_IRUGO | S_IWUSR);
60 MODULE_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
88 inline 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 }
96 EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
97
98 static 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
117 void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
118 {
119 __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
120 be32_to_cpu(hdr->max_cmdsn));
121 }
122 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
123
124 /**
125 * iscsi_prep_data_out_pdu - initialize Data-Out
126 * @task: scsi command task
127 * @r2t: R2T info
128 * @hdr: iscsi data in pdu
129 *
130 * Notes:
131 * Initialize Data-Out within this R2T sequence and finds
132 * proper data_offset within this SCSI command.
133 *
134 * This function is called with connection lock taken.
135 **/
136 void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
137 struct iscsi_data *hdr)
138 {
139 struct iscsi_conn *conn = task->conn;
140 unsigned int left = r2t->data_length - r2t->sent;
141
142 task->hdr_len = sizeof(struct iscsi_data);
143
144 memset(hdr, 0, sizeof(struct iscsi_data));
145 hdr->ttt = r2t->ttt;
146 hdr->datasn = cpu_to_be32(r2t->datasn);
147 r2t->datasn++;
148 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
149 hdr->lun = task->lun;
150 hdr->itt = task->hdr_itt;
151 hdr->exp_statsn = r2t->exp_statsn;
152 hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
153 if (left > conn->max_xmit_dlength) {
154 hton24(hdr->dlength, conn->max_xmit_dlength);
155 r2t->data_count = conn->max_xmit_dlength;
156 hdr->flags = 0;
157 } else {
158 hton24(hdr->dlength, left);
159 r2t->data_count = left;
160 hdr->flags = ISCSI_FLAG_CMD_FINAL;
161 }
162 conn->dataout_pdus_cnt++;
163 }
164 EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
165
166 static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
167 {
168 unsigned exp_len = task->hdr_len + len;
169
170 if (exp_len > task->hdr_max) {
171 WARN_ON(1);
172 return -EINVAL;
173 }
174
175 WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
176 task->hdr_len = exp_len;
177 return 0;
178 }
179
180 /*
181 * make an extended cdb AHS
182 */
183 static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
184 {
185 struct scsi_cmnd *cmd = task->sc;
186 unsigned rlen, pad_len;
187 unsigned short ahslength;
188 struct iscsi_ecdb_ahdr *ecdb_ahdr;
189 int rc;
190
191 ecdb_ahdr = iscsi_next_hdr(task);
192 rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
193
194 BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
195 ahslength = rlen + sizeof(ecdb_ahdr->reserved);
196
197 pad_len = iscsi_padding(rlen);
198
199 rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
200 sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
201 if (rc)
202 return rc;
203
204 if (pad_len)
205 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
206
207 ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
208 ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
209 ecdb_ahdr->reserved = 0;
210 memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
211
212 ISCSI_DBG_SESSION(task->conn->session,
213 "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
214 "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
215 "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
216 task->hdr_len);
217 return 0;
218 }
219
220 static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
221 {
222 struct scsi_cmnd *sc = task->sc;
223 struct iscsi_rlength_ahdr *rlen_ahdr;
224 int rc;
225
226 rlen_ahdr = iscsi_next_hdr(task);
227 rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
228 if (rc)
229 return rc;
230
231 rlen_ahdr->ahslength =
232 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
233 sizeof(rlen_ahdr->reserved));
234 rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
235 rlen_ahdr->reserved = 0;
236 rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
237
238 ISCSI_DBG_SESSION(task->conn->session,
239 "bidi-in rlen_ahdr->read_length(%d) "
240 "rlen_ahdr->ahslength(%d)\n",
241 be32_to_cpu(rlen_ahdr->read_length),
242 be16_to_cpu(rlen_ahdr->ahslength));
243 return 0;
244 }
245
246 /**
247 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
248 * @task: iscsi task
249 * @opcode: opcode to check for
250 *
251 * During TMF a task has to be checked if it's affected.
252 * All unrelated I/O can be passed through, but I/O to the
253 * affected LUN should be restricted.
254 * If 'fast_abort' is set we won't be sending any I/O to the
255 * affected LUN.
256 * Otherwise the target is waiting for all TTTs to be completed,
257 * so we have to send all outstanding Data-Out PDUs to the target.
258 */
259 static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
260 {
261 struct iscsi_conn *conn = task->conn;
262 struct iscsi_tm *tmf = &conn->tmhdr;
263 u64 hdr_lun;
264
265 if (conn->tmf_state == TMF_INITIAL)
266 return 0;
267
268 if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
269 return 0;
270
271 switch (ISCSI_TM_FUNC_VALUE(tmf)) {
272 case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
273 /*
274 * Allow PDUs for unrelated LUNs
275 */
276 hdr_lun = scsilun_to_int(&tmf->lun);
277 if (hdr_lun != task->sc->device->lun)
278 return 0;
279 /* fall through */
280 case ISCSI_TM_FUNC_TARGET_WARM_RESET:
281 /*
282 * Fail all SCSI cmd PDUs
283 */
284 if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
285 iscsi_conn_printk(KERN_INFO, conn,
286 "task [op %x/%x itt "
287 "0x%x/0x%x] "
288 "rejected.\n",
289 task->hdr->opcode, opcode,
290 task->itt, task->hdr_itt);
291 return -EACCES;
292 }
293 /*
294 * And also all data-out PDUs in response to R2T
295 * if fast_abort is set.
296 */
297 if (conn->session->fast_abort) {
298 iscsi_conn_printk(KERN_INFO, conn,
299 "task [op %x/%x itt "
300 "0x%x/0x%x] fast abort.\n",
301 task->hdr->opcode, opcode,
302 task->itt, task->hdr_itt);
303 return -EACCES;
304 }
305 break;
306 case ISCSI_TM_FUNC_ABORT_TASK:
307 /*
308 * the caller has already checked if the task
309 * they want to abort was in the pending queue so if
310 * we are here the cmd pdu has gone out already, and
311 * we will only hit this for data-outs
312 */
313 if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
314 task->hdr_itt == tmf->rtt) {
315 ISCSI_DBG_SESSION(conn->session,
316 "Preventing task %x/%x from sending "
317 "data-out due to abort task in "
318 "progress\n", task->itt,
319 task->hdr_itt);
320 return -EACCES;
321 }
322 break;
323 }
324
325 return 0;
326 }
327
328 /**
329 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
330 * @task: iscsi task
331 *
332 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
333 * fields like dlength or final based on how much data it sends
334 */
335 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
336 {
337 struct iscsi_conn *conn = task->conn;
338 struct iscsi_session *session = conn->session;
339 struct scsi_cmnd *sc = task->sc;
340 struct iscsi_scsi_req *hdr;
341 unsigned hdrlength, cmd_len, transfer_length;
342 itt_t itt;
343 int rc;
344
345 rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
346 if (rc)
347 return rc;
348
349 if (conn->session->tt->alloc_pdu) {
350 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
351 if (rc)
352 return rc;
353 }
354 hdr = (struct iscsi_scsi_req *)task->hdr;
355 itt = hdr->itt;
356 memset(hdr, 0, sizeof(*hdr));
357
358 if (session->tt->parse_pdu_itt)
359 hdr->itt = task->hdr_itt = itt;
360 else
361 hdr->itt = task->hdr_itt = build_itt(task->itt,
362 task->conn->session->age);
363 task->hdr_len = 0;
364 rc = iscsi_add_hdr(task, sizeof(*hdr));
365 if (rc)
366 return rc;
367 hdr->opcode = ISCSI_OP_SCSI_CMD;
368 hdr->flags = ISCSI_ATTR_SIMPLE;
369 int_to_scsilun(sc->device->lun, &hdr->lun);
370 task->lun = hdr->lun;
371 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
372 cmd_len = sc->cmd_len;
373 if (cmd_len < ISCSI_CDB_SIZE)
374 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
375 else if (cmd_len > ISCSI_CDB_SIZE) {
376 rc = iscsi_prep_ecdb_ahs(task);
377 if (rc)
378 return rc;
379 cmd_len = ISCSI_CDB_SIZE;
380 }
381 memcpy(hdr->cdb, sc->cmnd, cmd_len);
382
383 task->imm_count = 0;
384 if (scsi_bidi_cmnd(sc)) {
385 hdr->flags |= ISCSI_FLAG_CMD_READ;
386 rc = iscsi_prep_bidi_ahs(task);
387 if (rc)
388 return rc;
389 }
390
391 if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL)
392 task->protected = true;
393
394 transfer_length = scsi_transfer_length(sc);
395 hdr->data_length = cpu_to_be32(transfer_length);
396 if (sc->sc_data_direction == DMA_TO_DEVICE) {
397 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
398
399 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
400 /*
401 * Write counters:
402 *
403 * imm_count bytes to be sent right after
404 * SCSI PDU Header
405 *
406 * unsol_count bytes(as Data-Out) to be sent
407 * without R2T ack right after
408 * immediate data
409 *
410 * r2t data_length bytes to be sent via R2T ack's
411 *
412 * pad_count bytes to be sent as zero-padding
413 */
414 memset(r2t, 0, sizeof(*r2t));
415
416 if (session->imm_data_en) {
417 if (transfer_length >= session->first_burst)
418 task->imm_count = min(session->first_burst,
419 conn->max_xmit_dlength);
420 else
421 task->imm_count = min(transfer_length,
422 conn->max_xmit_dlength);
423 hton24(hdr->dlength, task->imm_count);
424 } else
425 zero_data(hdr->dlength);
426
427 if (!session->initial_r2t_en) {
428 r2t->data_length = min(session->first_burst,
429 transfer_length) -
430 task->imm_count;
431 r2t->data_offset = task->imm_count;
432 r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
433 r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
434 }
435
436 if (!task->unsol_r2t.data_length)
437 /* No unsolicit Data-Out's */
438 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
439 } else {
440 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
441 zero_data(hdr->dlength);
442
443 if (sc->sc_data_direction == DMA_FROM_DEVICE)
444 hdr->flags |= ISCSI_FLAG_CMD_READ;
445 }
446
447 /* calculate size of additional header segments (AHSs) */
448 hdrlength = task->hdr_len - sizeof(*hdr);
449
450 WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
451 hdrlength /= ISCSI_PAD_LEN;
452
453 WARN_ON(hdrlength >= 256);
454 hdr->hlength = hdrlength & 0xFF;
455 hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
456
457 if (session->tt->init_task && session->tt->init_task(task))
458 return -EIO;
459
460 task->state = ISCSI_TASK_RUNNING;
461 session->cmdsn++;
462
463 conn->scsicmd_pdus_cnt++;
464 ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
465 "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
466 scsi_bidi_cmnd(sc) ? "bidirectional" :
467 sc->sc_data_direction == DMA_TO_DEVICE ?
468 "write" : "read", conn->id, sc, sc->cmnd[0],
469 task->itt, transfer_length,
470 scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
471 session->cmdsn,
472 session->max_cmdsn - session->exp_cmdsn + 1);
473 return 0;
474 }
475
476 /**
477 * iscsi_free_task - free a task
478 * @task: iscsi cmd task
479 *
480 * Must be called with session back_lock.
481 * This function returns the scsi command to scsi-ml or cleans
482 * up mgmt tasks then returns the task to the pool.
483 */
484 static void iscsi_free_task(struct iscsi_task *task)
485 {
486 struct iscsi_conn *conn = task->conn;
487 struct iscsi_session *session = conn->session;
488 struct scsi_cmnd *sc = task->sc;
489 int oldstate = task->state;
490
491 ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
492 task->itt, task->state, task->sc);
493
494 session->tt->cleanup_task(task);
495 task->state = ISCSI_TASK_FREE;
496 task->sc = NULL;
497 /*
498 * login task is preallocated so do not free
499 */
500 if (conn->login_task == task)
501 return;
502
503 kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
504
505 if (sc) {
506 /* SCSI eh reuses commands to verify us */
507 sc->SCp.ptr = NULL;
508 /*
509 * queue command may call this to free the task, so
510 * it will decide how to return sc to scsi-ml.
511 */
512 if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
513 sc->scsi_done(sc);
514 }
515 }
516
517 void __iscsi_get_task(struct iscsi_task *task)
518 {
519 atomic_inc(&task->refcount);
520 }
521 EXPORT_SYMBOL_GPL(__iscsi_get_task);
522
523 void __iscsi_put_task(struct iscsi_task *task)
524 {
525 if (atomic_dec_and_test(&task->refcount))
526 iscsi_free_task(task);
527 }
528 EXPORT_SYMBOL_GPL(__iscsi_put_task);
529
530 void iscsi_put_task(struct iscsi_task *task)
531 {
532 struct iscsi_session *session = task->conn->session;
533
534 /* regular RX path uses back_lock */
535 spin_lock_bh(&session->back_lock);
536 __iscsi_put_task(task);
537 spin_unlock_bh(&session->back_lock);
538 }
539 EXPORT_SYMBOL_GPL(iscsi_put_task);
540
541 /**
542 * iscsi_complete_task - finish a task
543 * @task: iscsi cmd task
544 * @state: state to complete task with
545 *
546 * Must be called with session back_lock.
547 */
548 static void iscsi_complete_task(struct iscsi_task *task, int state)
549 {
550 struct iscsi_conn *conn = task->conn;
551
552 ISCSI_DBG_SESSION(conn->session,
553 "complete task itt 0x%x state %d sc %p\n",
554 task->itt, task->state, task->sc);
555 if (task->state == ISCSI_TASK_COMPLETED ||
556 task->state == ISCSI_TASK_ABRT_TMF ||
557 task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
558 task->state == ISCSI_TASK_REQUEUE_SCSIQ)
559 return;
560 WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
561 task->state = state;
562
563 if (!list_empty(&task->running))
564 list_del_init(&task->running);
565
566 if (conn->task == task)
567 conn->task = NULL;
568
569 if (conn->ping_task == task)
570 conn->ping_task = NULL;
571
572 /* release get from queueing */
573 __iscsi_put_task(task);
574 }
575
576 /**
577 * iscsi_complete_scsi_task - finish scsi task normally
578 * @task: iscsi task for scsi cmd
579 * @exp_cmdsn: expected cmd sn in cpu format
580 * @max_cmdsn: max cmd sn in cpu format
581 *
582 * This is used when drivers do not need or cannot perform
583 * lower level pdu processing.
584 *
585 * Called with session back_lock
586 */
587 void iscsi_complete_scsi_task(struct iscsi_task *task,
588 uint32_t exp_cmdsn, uint32_t max_cmdsn)
589 {
590 struct iscsi_conn *conn = task->conn;
591
592 ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
593
594 conn->last_recv = jiffies;
595 __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
596 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
597 }
598 EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
599
600
601 /*
602 * session back_lock must be held and if not called for a task that is
603 * still pending or from the xmit thread, then xmit thread must
604 * be suspended.
605 */
606 static void fail_scsi_task(struct iscsi_task *task, int err)
607 {
608 struct iscsi_conn *conn = task->conn;
609 struct scsi_cmnd *sc;
610 int state;
611
612 /*
613 * if a command completes and we get a successful tmf response
614 * we will hit this because the scsi eh abort code does not take
615 * a ref to the task.
616 */
617 sc = task->sc;
618 if (!sc)
619 return;
620
621 if (task->state == ISCSI_TASK_PENDING) {
622 /*
623 * cmd never made it to the xmit thread, so we should not count
624 * the cmd in the sequencing
625 */
626 conn->session->queued_cmdsn--;
627 /* it was never sent so just complete like normal */
628 state = ISCSI_TASK_COMPLETED;
629 } else if (err == DID_TRANSPORT_DISRUPTED)
630 state = ISCSI_TASK_ABRT_SESS_RECOV;
631 else
632 state = ISCSI_TASK_ABRT_TMF;
633
634 sc->result = err << 16;
635 if (!scsi_bidi_cmnd(sc))
636 scsi_set_resid(sc, scsi_bufflen(sc));
637 else {
638 scsi_out(sc)->resid = scsi_out(sc)->length;
639 scsi_in(sc)->resid = scsi_in(sc)->length;
640 }
641
642 /* regular RX path uses back_lock */
643 spin_lock_bh(&conn->session->back_lock);
644 iscsi_complete_task(task, state);
645 spin_unlock_bh(&conn->session->back_lock);
646 }
647
648 static 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
694 static 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 if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
721 iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN);
722 return NULL;
723 }
724
725 task = conn->login_task;
726 } else {
727 if (session->state != ISCSI_STATE_LOGGED_IN)
728 return NULL;
729
730 if (data_size != 0) {
731 iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
732 return NULL;
733 }
734
735 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
736 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
737
738 if (!kfifo_out(&session->cmdpool.queue,
739 (void*)&task, sizeof(void*)))
740 return NULL;
741 }
742 /*
743 * released in complete pdu for task we expect a response for, and
744 * released by the lld when it has transmitted the task for
745 * pdus we do not expect a response for.
746 */
747 atomic_set(&task->refcount, 1);
748 task->conn = conn;
749 task->sc = NULL;
750 INIT_LIST_HEAD(&task->running);
751 task->state = ISCSI_TASK_PENDING;
752
753 if (data_size) {
754 memcpy(task->data, data, data_size);
755 task->data_count = data_size;
756 } else
757 task->data_count = 0;
758
759 if (conn->session->tt->alloc_pdu) {
760 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
761 iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
762 "pdu for mgmt task.\n");
763 goto free_task;
764 }
765 }
766
767 itt = task->hdr->itt;
768 task->hdr_len = sizeof(struct iscsi_hdr);
769 memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
770
771 if (hdr->itt != RESERVED_ITT) {
772 if (session->tt->parse_pdu_itt)
773 task->hdr->itt = itt;
774 else
775 task->hdr->itt = build_itt(task->itt,
776 task->conn->session->age);
777 }
778
779 if (!ihost->workq) {
780 if (iscsi_prep_mgmt_task(conn, task))
781 goto free_task;
782
783 if (session->tt->xmit_task(task))
784 goto free_task;
785 } else {
786 list_add_tail(&task->running, &conn->mgmtqueue);
787 iscsi_conn_queue_work(conn);
788 }
789
790 return task;
791
792 free_task:
793 /* regular RX path uses back_lock */
794 spin_lock_bh(&session->back_lock);
795 __iscsi_put_task(task);
796 spin_unlock_bh(&session->back_lock);
797 return NULL;
798 }
799
800 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
801 char *data, uint32_t data_size)
802 {
803 struct iscsi_conn *conn = cls_conn->dd_data;
804 struct iscsi_session *session = conn->session;
805 int err = 0;
806
807 spin_lock_bh(&session->frwd_lock);
808 if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
809 err = -EPERM;
810 spin_unlock_bh(&session->frwd_lock);
811 return err;
812 }
813 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
814
815 /**
816 * iscsi_cmd_rsp - SCSI Command Response processing
817 * @conn: iscsi connection
818 * @hdr: iscsi header
819 * @task: scsi command task
820 * @data: cmd data buffer
821 * @datalen: len of buffer
822 *
823 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
824 * then completes the command and task.
825 **/
826 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
827 struct iscsi_task *task, char *data,
828 int datalen)
829 {
830 struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
831 struct iscsi_session *session = conn->session;
832 struct scsi_cmnd *sc = task->sc;
833
834 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
835 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
836
837 sc->result = (DID_OK << 16) | rhdr->cmd_status;
838
839 if (task->protected) {
840 sector_t sector;
841 u8 ascq;
842
843 /**
844 * Transports that didn't implement check_protection
845 * callback but still published T10-PI support to scsi-mid
846 * deserve this BUG_ON.
847 **/
848 BUG_ON(!session->tt->check_protection);
849
850 ascq = session->tt->check_protection(task, &sector);
851 if (ascq) {
852 sc->result = DRIVER_SENSE << 24 |
853 SAM_STAT_CHECK_CONDITION;
854 scsi_build_sense_buffer(1, sc->sense_buffer,
855 ILLEGAL_REQUEST, 0x10, ascq);
856 sc->sense_buffer[7] = 0xc; /* Additional sense length */
857 sc->sense_buffer[8] = 0; /* Information desc type */
858 sc->sense_buffer[9] = 0xa; /* Additional desc length */
859 sc->sense_buffer[10] = 0x80; /* Validity bit */
860
861 put_unaligned_be64(sector, &sc->sense_buffer[12]);
862 goto out;
863 }
864 }
865
866 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
867 sc->result = DID_ERROR << 16;
868 goto out;
869 }
870
871 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
872 uint16_t senselen;
873
874 if (datalen < 2) {
875 invalid_datalen:
876 iscsi_conn_printk(KERN_ERR, conn,
877 "Got CHECK_CONDITION but invalid data "
878 "buffer size of %d\n", datalen);
879 sc->result = DID_BAD_TARGET << 16;
880 goto out;
881 }
882
883 senselen = get_unaligned_be16(data);
884 if (datalen < senselen)
885 goto invalid_datalen;
886
887 memcpy(sc->sense_buffer, data + 2,
888 min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
889 ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
890 min_t(uint16_t, senselen,
891 SCSI_SENSE_BUFFERSIZE));
892 }
893
894 if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
895 ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
896 int res_count = be32_to_cpu(rhdr->bi_residual_count);
897
898 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
899 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
900 res_count <= scsi_in(sc)->length))
901 scsi_in(sc)->resid = res_count;
902 else
903 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
904 }
905
906 if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
907 ISCSI_FLAG_CMD_OVERFLOW)) {
908 int res_count = be32_to_cpu(rhdr->residual_count);
909
910 if (res_count > 0 &&
911 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
912 res_count <= scsi_bufflen(sc)))
913 /* write side for bidi or uni-io set_resid */
914 scsi_set_resid(sc, res_count);
915 else
916 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
917 }
918 out:
919 ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
920 sc, sc->result, task->itt);
921 conn->scsirsp_pdus_cnt++;
922 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
923 }
924
925 /**
926 * iscsi_data_in_rsp - SCSI Data-In Response processing
927 * @conn: iscsi connection
928 * @hdr: iscsi pdu
929 * @task: scsi command task
930 **/
931 static void
932 iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
933 struct iscsi_task *task)
934 {
935 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
936 struct scsi_cmnd *sc = task->sc;
937
938 if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
939 return;
940
941 iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
942 sc->result = (DID_OK << 16) | rhdr->cmd_status;
943 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
944 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
945 ISCSI_FLAG_DATA_OVERFLOW)) {
946 int res_count = be32_to_cpu(rhdr->residual_count);
947
948 if (res_count > 0 &&
949 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
950 res_count <= scsi_in(sc)->length))
951 scsi_in(sc)->resid = res_count;
952 else
953 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
954 }
955
956 ISCSI_DBG_SESSION(conn->session, "data in with status done "
957 "[sc %p res %d itt 0x%x]\n",
958 sc, sc->result, task->itt);
959 conn->scsirsp_pdus_cnt++;
960 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
961 }
962
963 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
964 {
965 struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
966
967 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
968 conn->tmfrsp_pdus_cnt++;
969
970 if (conn->tmf_state != TMF_QUEUED)
971 return;
972
973 if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
974 conn->tmf_state = TMF_SUCCESS;
975 else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
976 conn->tmf_state = TMF_NOT_FOUND;
977 else
978 conn->tmf_state = TMF_FAILED;
979 wake_up(&conn->ehwait);
980 }
981
982 static void iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
983 {
984 struct iscsi_nopout hdr;
985 struct iscsi_task *task;
986
987 if (!rhdr && conn->ping_task)
988 return;
989
990 memset(&hdr, 0, sizeof(struct iscsi_nopout));
991 hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
992 hdr.flags = ISCSI_FLAG_CMD_FINAL;
993
994 if (rhdr) {
995 hdr.lun = rhdr->lun;
996 hdr.ttt = rhdr->ttt;
997 hdr.itt = RESERVED_ITT;
998 } else
999 hdr.ttt = RESERVED_ITT;
1000
1001 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
1002 if (!task)
1003 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
1004 else if (!rhdr) {
1005 /* only track our nops */
1006 conn->ping_task = task;
1007 conn->last_ping = jiffies;
1008 }
1009 }
1010
1011 static int iscsi_nop_out_rsp(struct iscsi_task *task,
1012 struct iscsi_nopin *nop, char *data, int datalen)
1013 {
1014 struct iscsi_conn *conn = task->conn;
1015 int rc = 0;
1016
1017 if (conn->ping_task != task) {
1018 /*
1019 * If this is not in response to one of our
1020 * nops then it must be from userspace.
1021 */
1022 if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
1023 data, datalen))
1024 rc = ISCSI_ERR_CONN_FAILED;
1025 } else
1026 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
1027 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1028 return rc;
1029 }
1030
1031 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1032 char *data, int datalen)
1033 {
1034 struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1035 struct iscsi_hdr rejected_pdu;
1036 int opcode, rc = 0;
1037
1038 conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1039
1040 if (ntoh24(reject->dlength) > datalen ||
1041 ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1042 iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1043 "pdu. Invalid data length (pdu dlength "
1044 "%u, datalen %d\n", ntoh24(reject->dlength),
1045 datalen);
1046 return ISCSI_ERR_PROTO;
1047 }
1048 memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1049 opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1050
1051 switch (reject->reason) {
1052 case ISCSI_REASON_DATA_DIGEST_ERROR:
1053 iscsi_conn_printk(KERN_ERR, conn,
1054 "pdu (op 0x%x itt 0x%x) rejected "
1055 "due to DataDigest error.\n",
1056 opcode, rejected_pdu.itt);
1057 break;
1058 case ISCSI_REASON_IMM_CMD_REJECT:
1059 iscsi_conn_printk(KERN_ERR, conn,
1060 "pdu (op 0x%x itt 0x%x) rejected. Too many "
1061 "immediate commands.\n",
1062 opcode, rejected_pdu.itt);
1063 /*
1064 * We only send one TMF at a time so if the target could not
1065 * handle it, then it should get fixed (RFC mandates that
1066 * a target can handle one immediate TMF per conn).
1067 *
1068 * For nops-outs, we could have sent more than one if
1069 * the target is sending us lots of nop-ins
1070 */
1071 if (opcode != ISCSI_OP_NOOP_OUT)
1072 return 0;
1073
1074 if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1075 /*
1076 * nop-out in response to target's nop-out rejected.
1077 * Just resend.
1078 */
1079 /* In RX path we are under back lock */
1080 spin_unlock(&conn->session->back_lock);
1081 spin_lock(&conn->session->frwd_lock);
1082 iscsi_send_nopout(conn,
1083 (struct iscsi_nopin*)&rejected_pdu);
1084 spin_unlock(&conn->session->frwd_lock);
1085 spin_lock(&conn->session->back_lock);
1086 } else {
1087 struct iscsi_task *task;
1088 /*
1089 * Our nop as ping got dropped. We know the target
1090 * and transport are ok so just clean up
1091 */
1092 task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1093 if (!task) {
1094 iscsi_conn_printk(KERN_ERR, conn,
1095 "Invalid pdu reject. Could "
1096 "not lookup rejected task.\n");
1097 rc = ISCSI_ERR_BAD_ITT;
1098 } else
1099 rc = iscsi_nop_out_rsp(task,
1100 (struct iscsi_nopin*)&rejected_pdu,
1101 NULL, 0);
1102 }
1103 break;
1104 default:
1105 iscsi_conn_printk(KERN_ERR, conn,
1106 "pdu (op 0x%x itt 0x%x) rejected. Reason "
1107 "code 0x%x\n", rejected_pdu.opcode,
1108 rejected_pdu.itt, reject->reason);
1109 break;
1110 }
1111 return rc;
1112 }
1113
1114 /**
1115 * iscsi_itt_to_task - look up task by itt
1116 * @conn: iscsi connection
1117 * @itt: itt
1118 *
1119 * This should be used for mgmt tasks like login and nops, or if
1120 * the LDD's itt space does not include the session age.
1121 *
1122 * The session back_lock must be held.
1123 */
1124 struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1125 {
1126 struct iscsi_session *session = conn->session;
1127 int i;
1128
1129 if (itt == RESERVED_ITT)
1130 return NULL;
1131
1132 if (session->tt->parse_pdu_itt)
1133 session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1134 else
1135 i = get_itt(itt);
1136 if (i >= session->cmds_max)
1137 return NULL;
1138
1139 return session->cmds[i];
1140 }
1141 EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1142
1143 /**
1144 * __iscsi_complete_pdu - complete pdu
1145 * @conn: iscsi conn
1146 * @hdr: iscsi header
1147 * @data: data buffer
1148 * @datalen: len of data buffer
1149 *
1150 * Completes pdu processing by freeing any resources allocated at
1151 * queuecommand or send generic. session back_lock must be held and verify
1152 * itt must have been called.
1153 */
1154 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1155 char *data, int datalen)
1156 {
1157 struct iscsi_session *session = conn->session;
1158 int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1159 struct iscsi_task *task;
1160 uint32_t itt;
1161
1162 conn->last_recv = jiffies;
1163 rc = iscsi_verify_itt(conn, hdr->itt);
1164 if (rc)
1165 return rc;
1166
1167 if (hdr->itt != RESERVED_ITT)
1168 itt = get_itt(hdr->itt);
1169 else
1170 itt = ~0U;
1171
1172 ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1173 opcode, conn->id, itt, datalen);
1174
1175 if (itt == ~0U) {
1176 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1177
1178 switch(opcode) {
1179 case ISCSI_OP_NOOP_IN:
1180 if (datalen) {
1181 rc = ISCSI_ERR_PROTO;
1182 break;
1183 }
1184
1185 if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1186 break;
1187
1188 /* In RX path we are under back lock */
1189 spin_unlock(&session->back_lock);
1190 spin_lock(&session->frwd_lock);
1191 iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1192 spin_unlock(&session->frwd_lock);
1193 spin_lock(&session->back_lock);
1194 break;
1195 case ISCSI_OP_REJECT:
1196 rc = iscsi_handle_reject(conn, hdr, data, datalen);
1197 break;
1198 case ISCSI_OP_ASYNC_EVENT:
1199 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1200 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1201 rc = ISCSI_ERR_CONN_FAILED;
1202 break;
1203 default:
1204 rc = ISCSI_ERR_BAD_OPCODE;
1205 break;
1206 }
1207 goto out;
1208 }
1209
1210 switch(opcode) {
1211 case ISCSI_OP_SCSI_CMD_RSP:
1212 case ISCSI_OP_SCSI_DATA_IN:
1213 task = iscsi_itt_to_ctask(conn, hdr->itt);
1214 if (!task)
1215 return ISCSI_ERR_BAD_ITT;
1216 task->last_xfer = jiffies;
1217 break;
1218 case ISCSI_OP_R2T:
1219 /*
1220 * LLD handles R2Ts if they need to.
1221 */
1222 return 0;
1223 case ISCSI_OP_LOGOUT_RSP:
1224 case ISCSI_OP_LOGIN_RSP:
1225 case ISCSI_OP_TEXT_RSP:
1226 case ISCSI_OP_SCSI_TMFUNC_RSP:
1227 case ISCSI_OP_NOOP_IN:
1228 task = iscsi_itt_to_task(conn, hdr->itt);
1229 if (!task)
1230 return ISCSI_ERR_BAD_ITT;
1231 break;
1232 default:
1233 return ISCSI_ERR_BAD_OPCODE;
1234 }
1235
1236 switch(opcode) {
1237 case ISCSI_OP_SCSI_CMD_RSP:
1238 iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1239 break;
1240 case ISCSI_OP_SCSI_DATA_IN:
1241 iscsi_data_in_rsp(conn, hdr, task);
1242 break;
1243 case ISCSI_OP_LOGOUT_RSP:
1244 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1245 if (datalen) {
1246 rc = ISCSI_ERR_PROTO;
1247 break;
1248 }
1249 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1250 goto recv_pdu;
1251 case ISCSI_OP_LOGIN_RSP:
1252 case ISCSI_OP_TEXT_RSP:
1253 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1254 /*
1255 * login related PDU's exp_statsn is handled in
1256 * userspace
1257 */
1258 goto recv_pdu;
1259 case ISCSI_OP_SCSI_TMFUNC_RSP:
1260 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1261 if (datalen) {
1262 rc = ISCSI_ERR_PROTO;
1263 break;
1264 }
1265
1266 iscsi_tmf_rsp(conn, hdr);
1267 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1268 break;
1269 case ISCSI_OP_NOOP_IN:
1270 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1271 if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1272 rc = ISCSI_ERR_PROTO;
1273 break;
1274 }
1275 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1276
1277 rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1278 data, datalen);
1279 break;
1280 default:
1281 rc = ISCSI_ERR_BAD_OPCODE;
1282 break;
1283 }
1284
1285 out:
1286 return rc;
1287 recv_pdu:
1288 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1289 rc = ISCSI_ERR_CONN_FAILED;
1290 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1291 return rc;
1292 }
1293 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1294
1295 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1296 char *data, int datalen)
1297 {
1298 int rc;
1299
1300 spin_lock(&conn->session->back_lock);
1301 rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1302 spin_unlock(&conn->session->back_lock);
1303 return rc;
1304 }
1305 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1306
1307 int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1308 {
1309 struct iscsi_session *session = conn->session;
1310 int age = 0, i = 0;
1311
1312 if (itt == RESERVED_ITT)
1313 return 0;
1314
1315 if (session->tt->parse_pdu_itt)
1316 session->tt->parse_pdu_itt(conn, itt, &i, &age);
1317 else {
1318 i = get_itt(itt);
1319 age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1320 }
1321
1322 if (age != session->age) {
1323 iscsi_conn_printk(KERN_ERR, conn,
1324 "received itt %x expected session age (%x)\n",
1325 (__force u32)itt, session->age);
1326 return ISCSI_ERR_BAD_ITT;
1327 }
1328
1329 if (i >= session->cmds_max) {
1330 iscsi_conn_printk(KERN_ERR, conn,
1331 "received invalid itt index %u (max cmds "
1332 "%u.\n", i, session->cmds_max);
1333 return ISCSI_ERR_BAD_ITT;
1334 }
1335 return 0;
1336 }
1337 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1338
1339 /**
1340 * iscsi_itt_to_ctask - look up ctask by itt
1341 * @conn: iscsi connection
1342 * @itt: itt
1343 *
1344 * This should be used for cmd tasks.
1345 *
1346 * The session back_lock must be held.
1347 */
1348 struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1349 {
1350 struct iscsi_task *task;
1351
1352 if (iscsi_verify_itt(conn, itt))
1353 return NULL;
1354
1355 task = iscsi_itt_to_task(conn, itt);
1356 if (!task || !task->sc)
1357 return NULL;
1358
1359 if (task->sc->SCp.phase != conn->session->age) {
1360 iscsi_session_printk(KERN_ERR, conn->session,
1361 "task's session age %d, expected %d\n",
1362 task->sc->SCp.phase, conn->session->age);
1363 return NULL;
1364 }
1365
1366 return task;
1367 }
1368 EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1369
1370 void iscsi_session_failure(struct iscsi_session *session,
1371 enum iscsi_err err)
1372 {
1373 struct iscsi_conn *conn;
1374 struct device *dev;
1375
1376 spin_lock_bh(&session->frwd_lock);
1377 conn = session->leadconn;
1378 if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1379 spin_unlock_bh(&session->frwd_lock);
1380 return;
1381 }
1382
1383 dev = get_device(&conn->cls_conn->dev);
1384 spin_unlock_bh(&session->frwd_lock);
1385 if (!dev)
1386 return;
1387 /*
1388 * if the host is being removed bypass the connection
1389 * recovery initialization because we are going to kill
1390 * the session.
1391 */
1392 if (err == ISCSI_ERR_INVALID_HOST)
1393 iscsi_conn_error_event(conn->cls_conn, err);
1394 else
1395 iscsi_conn_failure(conn, err);
1396 put_device(dev);
1397 }
1398 EXPORT_SYMBOL_GPL(iscsi_session_failure);
1399
1400 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1401 {
1402 struct iscsi_session *session = conn->session;
1403
1404 spin_lock_bh(&session->frwd_lock);
1405 if (session->state == ISCSI_STATE_FAILED) {
1406 spin_unlock_bh(&session->frwd_lock);
1407 return;
1408 }
1409
1410 if (conn->stop_stage == 0)
1411 session->state = ISCSI_STATE_FAILED;
1412 spin_unlock_bh(&session->frwd_lock);
1413
1414 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1415 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1416 iscsi_conn_error_event(conn->cls_conn, err);
1417 }
1418 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1419
1420 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1421 {
1422 struct iscsi_session *session = conn->session;
1423
1424 /*
1425 * Check for iSCSI window and take care of CmdSN wrap-around
1426 */
1427 if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1428 ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1429 "%u MaxCmdSN %u CmdSN %u/%u\n",
1430 session->exp_cmdsn, session->max_cmdsn,
1431 session->cmdsn, session->queued_cmdsn);
1432 return -ENOSPC;
1433 }
1434 return 0;
1435 }
1436
1437 static int iscsi_xmit_task(struct iscsi_conn *conn)
1438 {
1439 struct iscsi_task *task = conn->task;
1440 int rc;
1441
1442 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
1443 return -ENODATA;
1444
1445 __iscsi_get_task(task);
1446 spin_unlock_bh(&conn->session->frwd_lock);
1447 rc = conn->session->tt->xmit_task(task);
1448 spin_lock_bh(&conn->session->frwd_lock);
1449 if (!rc) {
1450 /* done with this task */
1451 task->last_xfer = jiffies;
1452 conn->task = NULL;
1453 }
1454 /* regular RX path uses back_lock */
1455 spin_lock(&conn->session->back_lock);
1456 __iscsi_put_task(task);
1457 spin_unlock(&conn->session->back_lock);
1458 return rc;
1459 }
1460
1461 /**
1462 * iscsi_requeue_task - requeue task to run from session workqueue
1463 * @task: task to requeue
1464 *
1465 * LLDs that need to run a task from the session workqueue should call
1466 * this. The session frwd_lock must be held. This should only be called
1467 * by software drivers.
1468 */
1469 void iscsi_requeue_task(struct iscsi_task *task)
1470 {
1471 struct iscsi_conn *conn = task->conn;
1472
1473 /*
1474 * this may be on the requeue list already if the xmit_task callout
1475 * is handling the r2ts while we are adding new ones
1476 */
1477 if (list_empty(&task->running))
1478 list_add_tail(&task->running, &conn->requeue);
1479 iscsi_conn_queue_work(conn);
1480 }
1481 EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1482
1483 /**
1484 * iscsi_data_xmit - xmit any command into the scheduled connection
1485 * @conn: iscsi connection
1486 *
1487 * Notes:
1488 * The function can return -EAGAIN in which case the caller must
1489 * re-schedule it again later or recover. '0' return code means
1490 * successful xmit.
1491 **/
1492 static int iscsi_data_xmit(struct iscsi_conn *conn)
1493 {
1494 struct iscsi_task *task;
1495 int rc = 0;
1496
1497 spin_lock_bh(&conn->session->frwd_lock);
1498 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1499 ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1500 spin_unlock_bh(&conn->session->frwd_lock);
1501 return -ENODATA;
1502 }
1503
1504 if (conn->task) {
1505 rc = iscsi_xmit_task(conn);
1506 if (rc)
1507 goto done;
1508 }
1509
1510 /*
1511 * process mgmt pdus like nops before commands since we should
1512 * only have one nop-out as a ping from us and targets should not
1513 * overflow us with nop-ins
1514 */
1515 check_mgmt:
1516 while (!list_empty(&conn->mgmtqueue)) {
1517 conn->task = list_entry(conn->mgmtqueue.next,
1518 struct iscsi_task, running);
1519 list_del_init(&conn->task->running);
1520 if (iscsi_prep_mgmt_task(conn, conn->task)) {
1521 /* regular RX path uses back_lock */
1522 spin_lock_bh(&conn->session->back_lock);
1523 __iscsi_put_task(conn->task);
1524 spin_unlock_bh(&conn->session->back_lock);
1525 conn->task = NULL;
1526 continue;
1527 }
1528 rc = iscsi_xmit_task(conn);
1529 if (rc)
1530 goto done;
1531 }
1532
1533 /* process pending command queue */
1534 while (!list_empty(&conn->cmdqueue)) {
1535 conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1536 running);
1537 list_del_init(&conn->task->running);
1538 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1539 fail_scsi_task(conn->task, DID_IMM_RETRY);
1540 continue;
1541 }
1542 rc = iscsi_prep_scsi_cmd_pdu(conn->task);
1543 if (rc) {
1544 if (rc == -ENOMEM || rc == -EACCES) {
1545 list_add_tail(&conn->task->running,
1546 &conn->cmdqueue);
1547 conn->task = NULL;
1548 goto done;
1549 } else
1550 fail_scsi_task(conn->task, DID_ABORT);
1551 continue;
1552 }
1553 rc = iscsi_xmit_task(conn);
1554 if (rc)
1555 goto done;
1556 /*
1557 * we could continuously get new task requests so
1558 * we need to check the mgmt queue for nops that need to
1559 * be sent to aviod starvation
1560 */
1561 if (!list_empty(&conn->mgmtqueue))
1562 goto check_mgmt;
1563 }
1564
1565 while (!list_empty(&conn->requeue)) {
1566 /*
1567 * we always do fastlogout - conn stop code will clean up.
1568 */
1569 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1570 break;
1571
1572 task = list_entry(conn->requeue.next, struct iscsi_task,
1573 running);
1574 if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1575 break;
1576
1577 conn->task = task;
1578 list_del_init(&conn->task->running);
1579 conn->task->state = ISCSI_TASK_RUNNING;
1580 rc = iscsi_xmit_task(conn);
1581 if (rc)
1582 goto done;
1583 if (!list_empty(&conn->mgmtqueue))
1584 goto check_mgmt;
1585 }
1586 spin_unlock_bh(&conn->session->frwd_lock);
1587 return -ENODATA;
1588
1589 done:
1590 spin_unlock_bh(&conn->session->frwd_lock);
1591 return rc;
1592 }
1593
1594 static void iscsi_xmitworker(struct work_struct *work)
1595 {
1596 struct iscsi_conn *conn =
1597 container_of(work, struct iscsi_conn, xmitwork);
1598 int rc;
1599 /*
1600 * serialize Xmit worker on a per-connection basis.
1601 */
1602 do {
1603 rc = iscsi_data_xmit(conn);
1604 } while (rc >= 0 || rc == -EAGAIN);
1605 }
1606
1607 static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1608 struct scsi_cmnd *sc)
1609 {
1610 struct iscsi_task *task;
1611
1612 if (!kfifo_out(&conn->session->cmdpool.queue,
1613 (void *) &task, sizeof(void *)))
1614 return NULL;
1615
1616 sc->SCp.phase = conn->session->age;
1617 sc->SCp.ptr = (char *) task;
1618
1619 atomic_set(&task->refcount, 1);
1620 task->state = ISCSI_TASK_PENDING;
1621 task->conn = conn;
1622 task->sc = sc;
1623 task->have_checked_conn = false;
1624 task->last_timeout = jiffies;
1625 task->last_xfer = jiffies;
1626 task->protected = false;
1627 INIT_LIST_HEAD(&task->running);
1628 return task;
1629 }
1630
1631 enum {
1632 FAILURE_BAD_HOST = 1,
1633 FAILURE_SESSION_FAILED,
1634 FAILURE_SESSION_FREED,
1635 FAILURE_WINDOW_CLOSED,
1636 FAILURE_OOM,
1637 FAILURE_SESSION_TERMINATE,
1638 FAILURE_SESSION_IN_RECOVERY,
1639 FAILURE_SESSION_RECOVERY_TIMEOUT,
1640 FAILURE_SESSION_LOGGING_OUT,
1641 FAILURE_SESSION_NOT_READY,
1642 };
1643
1644 int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1645 {
1646 struct iscsi_cls_session *cls_session;
1647 struct iscsi_host *ihost;
1648 int reason = 0;
1649 struct iscsi_session *session;
1650 struct iscsi_conn *conn;
1651 struct iscsi_task *task = NULL;
1652
1653 sc->result = 0;
1654 sc->SCp.ptr = NULL;
1655
1656 ihost = shost_priv(host);
1657
1658 cls_session = starget_to_session(scsi_target(sc->device));
1659 session = cls_session->dd_data;
1660 spin_lock_bh(&session->frwd_lock);
1661
1662 reason = iscsi_session_chkready(cls_session);
1663 if (reason) {
1664 sc->result = reason;
1665 goto fault;
1666 }
1667
1668 if (session->state != ISCSI_STATE_LOGGED_IN) {
1669 /*
1670 * to handle the race between when we set the recovery state
1671 * and block the session we requeue here (commands could
1672 * be entering our queuecommand while a block is starting
1673 * up because the block code is not locked)
1674 */
1675 switch (session->state) {
1676 case ISCSI_STATE_FAILED:
1677 case ISCSI_STATE_IN_RECOVERY:
1678 reason = FAILURE_SESSION_IN_RECOVERY;
1679 sc->result = DID_IMM_RETRY << 16;
1680 break;
1681 case ISCSI_STATE_LOGGING_OUT:
1682 reason = FAILURE_SESSION_LOGGING_OUT;
1683 sc->result = DID_IMM_RETRY << 16;
1684 break;
1685 case ISCSI_STATE_RECOVERY_FAILED:
1686 reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1687 sc->result = DID_TRANSPORT_FAILFAST << 16;
1688 break;
1689 case ISCSI_STATE_TERMINATE:
1690 reason = FAILURE_SESSION_TERMINATE;
1691 sc->result = DID_NO_CONNECT << 16;
1692 break;
1693 default:
1694 reason = FAILURE_SESSION_FREED;
1695 sc->result = DID_NO_CONNECT << 16;
1696 }
1697 goto fault;
1698 }
1699
1700 conn = session->leadconn;
1701 if (!conn) {
1702 reason = FAILURE_SESSION_FREED;
1703 sc->result = DID_NO_CONNECT << 16;
1704 goto fault;
1705 }
1706
1707 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1708 reason = FAILURE_SESSION_IN_RECOVERY;
1709 sc->result = DID_REQUEUE;
1710 goto fault;
1711 }
1712
1713 if (iscsi_check_cmdsn_window_closed(conn)) {
1714 reason = FAILURE_WINDOW_CLOSED;
1715 goto reject;
1716 }
1717
1718 task = iscsi_alloc_task(conn, sc);
1719 if (!task) {
1720 reason = FAILURE_OOM;
1721 goto reject;
1722 }
1723
1724 if (!ihost->workq) {
1725 reason = iscsi_prep_scsi_cmd_pdu(task);
1726 if (reason) {
1727 if (reason == -ENOMEM || reason == -EACCES) {
1728 reason = FAILURE_OOM;
1729 goto prepd_reject;
1730 } else {
1731 sc->result = DID_ABORT << 16;
1732 goto prepd_fault;
1733 }
1734 }
1735 if (session->tt->xmit_task(task)) {
1736 session->cmdsn--;
1737 reason = FAILURE_SESSION_NOT_READY;
1738 goto prepd_reject;
1739 }
1740 } else {
1741 list_add_tail(&task->running, &conn->cmdqueue);
1742 iscsi_conn_queue_work(conn);
1743 }
1744
1745 session->queued_cmdsn++;
1746 spin_unlock_bh(&session->frwd_lock);
1747 return 0;
1748
1749 prepd_reject:
1750 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1751 reject:
1752 spin_unlock_bh(&session->frwd_lock);
1753 ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1754 sc->cmnd[0], reason);
1755 return SCSI_MLQUEUE_TARGET_BUSY;
1756
1757 prepd_fault:
1758 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1759 fault:
1760 spin_unlock_bh(&session->frwd_lock);
1761 ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1762 sc->cmnd[0], reason);
1763 if (!scsi_bidi_cmnd(sc))
1764 scsi_set_resid(sc, scsi_bufflen(sc));
1765 else {
1766 scsi_out(sc)->resid = scsi_out(sc)->length;
1767 scsi_in(sc)->resid = scsi_in(sc)->length;
1768 }
1769 sc->scsi_done(sc);
1770 return 0;
1771 }
1772 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1773
1774 int iscsi_target_alloc(struct scsi_target *starget)
1775 {
1776 struct iscsi_cls_session *cls_session = starget_to_session(starget);
1777 struct iscsi_session *session = cls_session->dd_data;
1778
1779 starget->can_queue = session->scsi_cmds_max;
1780 return 0;
1781 }
1782 EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1783
1784 static void iscsi_tmf_timedout(unsigned long data)
1785 {
1786 struct iscsi_conn *conn = (struct iscsi_conn *)data;
1787 struct iscsi_session *session = conn->session;
1788
1789 spin_lock(&session->frwd_lock);
1790 if (conn->tmf_state == TMF_QUEUED) {
1791 conn->tmf_state = TMF_TIMEDOUT;
1792 ISCSI_DBG_EH(session, "tmf timedout\n");
1793 /* unblock eh_abort() */
1794 wake_up(&conn->ehwait);
1795 }
1796 spin_unlock(&session->frwd_lock);
1797 }
1798
1799 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1800 struct iscsi_tm *hdr, int age,
1801 int timeout)
1802 {
1803 struct iscsi_session *session = conn->session;
1804 struct iscsi_task *task;
1805
1806 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1807 NULL, 0);
1808 if (!task) {
1809 spin_unlock_bh(&session->frwd_lock);
1810 iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1811 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1812 spin_lock_bh(&session->frwd_lock);
1813 return -EPERM;
1814 }
1815 conn->tmfcmd_pdus_cnt++;
1816 conn->tmf_timer.expires = timeout * HZ + jiffies;
1817 conn->tmf_timer.function = iscsi_tmf_timedout;
1818 conn->tmf_timer.data = (unsigned long)conn;
1819 add_timer(&conn->tmf_timer);
1820 ISCSI_DBG_EH(session, "tmf set timeout\n");
1821
1822 spin_unlock_bh(&session->frwd_lock);
1823 mutex_unlock(&session->eh_mutex);
1824
1825 /*
1826 * block eh thread until:
1827 *
1828 * 1) tmf response
1829 * 2) tmf timeout
1830 * 3) session is terminated or restarted or userspace has
1831 * given up on recovery
1832 */
1833 wait_event_interruptible(conn->ehwait, age != session->age ||
1834 session->state != ISCSI_STATE_LOGGED_IN ||
1835 conn->tmf_state != TMF_QUEUED);
1836 if (signal_pending(current))
1837 flush_signals(current);
1838 del_timer_sync(&conn->tmf_timer);
1839
1840 mutex_lock(&session->eh_mutex);
1841 spin_lock_bh(&session->frwd_lock);
1842 /* if the session drops it will clean up the task */
1843 if (age != session->age ||
1844 session->state != ISCSI_STATE_LOGGED_IN)
1845 return -ENOTCONN;
1846 return 0;
1847 }
1848
1849 /*
1850 * Fail commands. session lock held and recv side suspended and xmit
1851 * thread flushed
1852 */
1853 static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error)
1854 {
1855 struct iscsi_task *task;
1856 int i;
1857
1858 for (i = 0; i < conn->session->cmds_max; i++) {
1859 task = conn->session->cmds[i];
1860 if (!task->sc || task->state == ISCSI_TASK_FREE)
1861 continue;
1862
1863 if (lun != -1 && lun != task->sc->device->lun)
1864 continue;
1865
1866 ISCSI_DBG_SESSION(conn->session,
1867 "failing sc %p itt 0x%x state %d\n",
1868 task->sc, task->itt, task->state);
1869 fail_scsi_task(task, error);
1870 }
1871 }
1872
1873 /**
1874 * iscsi_suspend_queue - suspend iscsi_queuecommand
1875 * @conn: iscsi conn to stop queueing IO on
1876 *
1877 * This grabs the session frwd_lock to make sure no one is in
1878 * xmit_task/queuecommand, and then sets suspend to prevent
1879 * new commands from being queued. This only needs to be called
1880 * by offload drivers that need to sync a path like ep disconnect
1881 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1882 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1883 */
1884 void iscsi_suspend_queue(struct iscsi_conn *conn)
1885 {
1886 spin_lock_bh(&conn->session->frwd_lock);
1887 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1888 spin_unlock_bh(&conn->session->frwd_lock);
1889 }
1890 EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1891
1892 /**
1893 * iscsi_suspend_tx - suspend iscsi_data_xmit
1894 * @conn: iscsi conn tp stop processing IO on.
1895 *
1896 * This function sets the suspend bit to prevent iscsi_data_xmit
1897 * from sending new IO, and if work is queued on the xmit thread
1898 * it will wait for it to be completed.
1899 */
1900 void iscsi_suspend_tx(struct iscsi_conn *conn)
1901 {
1902 struct Scsi_Host *shost = conn->session->host;
1903 struct iscsi_host *ihost = shost_priv(shost);
1904
1905 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1906 if (ihost->workq)
1907 flush_workqueue(ihost->workq);
1908 }
1909 EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1910
1911 static void iscsi_start_tx(struct iscsi_conn *conn)
1912 {
1913 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1914 iscsi_conn_queue_work(conn);
1915 }
1916
1917 /*
1918 * We want to make sure a ping is in flight. It has timed out.
1919 * And we are not busy processing a pdu that is making
1920 * progress but got started before the ping and is taking a while
1921 * to complete so the ping is just stuck behind it in a queue.
1922 */
1923 static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1924 {
1925 if (conn->ping_task &&
1926 time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1927 (conn->ping_timeout * HZ), jiffies))
1928 return 1;
1929 else
1930 return 0;
1931 }
1932
1933 static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1934 {
1935 enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
1936 struct iscsi_task *task = NULL, *running_task;
1937 struct iscsi_cls_session *cls_session;
1938 struct iscsi_session *session;
1939 struct iscsi_conn *conn;
1940 int i;
1941
1942 cls_session = starget_to_session(scsi_target(sc->device));
1943 session = cls_session->dd_data;
1944
1945 ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1946
1947 spin_lock(&session->frwd_lock);
1948 task = (struct iscsi_task *)sc->SCp.ptr;
1949 if (!task) {
1950 /*
1951 * Raced with completion. Blk layer has taken ownership
1952 * so let timeout code complete it now.
1953 */
1954 rc = BLK_EH_HANDLED;
1955 goto done;
1956 }
1957
1958 if (session->state != ISCSI_STATE_LOGGED_IN) {
1959 /*
1960 * We are probably in the middle of iscsi recovery so let
1961 * that complete and handle the error.
1962 */
1963 rc = BLK_EH_RESET_TIMER;
1964 goto done;
1965 }
1966
1967 conn = session->leadconn;
1968 if (!conn) {
1969 /* In the middle of shuting down */
1970 rc = BLK_EH_RESET_TIMER;
1971 goto done;
1972 }
1973
1974 /*
1975 * If we have sent (at least queued to the network layer) a pdu or
1976 * recvd one for the task since the last timeout ask for
1977 * more time. If on the next timeout we have not made progress
1978 * we can check if it is the task or connection when we send the
1979 * nop as a ping.
1980 */
1981 if (time_after(task->last_xfer, task->last_timeout)) {
1982 ISCSI_DBG_EH(session, "Command making progress. Asking "
1983 "scsi-ml for more time to complete. "
1984 "Last data xfer at %lu. Last timeout was at "
1985 "%lu\n.", task->last_xfer, task->last_timeout);
1986 task->have_checked_conn = false;
1987 rc = BLK_EH_RESET_TIMER;
1988 goto done;
1989 }
1990
1991 if (!conn->recv_timeout && !conn->ping_timeout)
1992 goto done;
1993 /*
1994 * if the ping timedout then we are in the middle of cleaning up
1995 * and can let the iscsi eh handle it
1996 */
1997 if (iscsi_has_ping_timed_out(conn)) {
1998 rc = BLK_EH_RESET_TIMER;
1999 goto done;
2000 }
2001
2002 for (i = 0; i < conn->session->cmds_max; i++) {
2003 running_task = conn->session->cmds[i];
2004 if (!running_task->sc || running_task == task ||
2005 running_task->state != ISCSI_TASK_RUNNING)
2006 continue;
2007
2008 /*
2009 * Only check if cmds started before this one have made
2010 * progress, or this could never fail
2011 */
2012 if (time_after(running_task->sc->jiffies_at_alloc,
2013 task->sc->jiffies_at_alloc))
2014 continue;
2015
2016 if (time_after(running_task->last_xfer, task->last_timeout)) {
2017 /*
2018 * This task has not made progress, but a task
2019 * started before us has transferred data since
2020 * we started/last-checked. We could be queueing
2021 * too many tasks or the LU is bad.
2022 *
2023 * If the device is bad the cmds ahead of us on
2024 * other devs will complete, and this loop will
2025 * eventually fail starting the scsi eh.
2026 */
2027 ISCSI_DBG_EH(session, "Command has not made progress "
2028 "but commands ahead of it have. "
2029 "Asking scsi-ml for more time to "
2030 "complete. Our last xfer vs running task "
2031 "last xfer %lu/%lu. Last check %lu.\n",
2032 task->last_xfer, running_task->last_xfer,
2033 task->last_timeout);
2034 rc = BLK_EH_RESET_TIMER;
2035 goto done;
2036 }
2037 }
2038
2039 /* Assumes nop timeout is shorter than scsi cmd timeout */
2040 if (task->have_checked_conn)
2041 goto done;
2042
2043 /*
2044 * Checking the transport already or nop from a cmd timeout still
2045 * running
2046 */
2047 if (conn->ping_task) {
2048 task->have_checked_conn = true;
2049 rc = BLK_EH_RESET_TIMER;
2050 goto done;
2051 }
2052
2053 /* Make sure there is a transport check done */
2054 iscsi_send_nopout(conn, NULL);
2055 task->have_checked_conn = true;
2056 rc = BLK_EH_RESET_TIMER;
2057
2058 done:
2059 if (task)
2060 task->last_timeout = jiffies;
2061 spin_unlock(&session->frwd_lock);
2062 ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2063 "timer reset" : "nh");
2064 return rc;
2065 }
2066
2067 static void iscsi_check_transport_timeouts(unsigned long data)
2068 {
2069 struct iscsi_conn *conn = (struct iscsi_conn *)data;
2070 struct iscsi_session *session = conn->session;
2071 unsigned long recv_timeout, next_timeout = 0, last_recv;
2072
2073 spin_lock(&session->frwd_lock);
2074 if (session->state != ISCSI_STATE_LOGGED_IN)
2075 goto done;
2076
2077 recv_timeout = conn->recv_timeout;
2078 if (!recv_timeout)
2079 goto done;
2080
2081 recv_timeout *= HZ;
2082 last_recv = conn->last_recv;
2083
2084 if (iscsi_has_ping_timed_out(conn)) {
2085 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2086 "expired, recv timeout %d, last rx %lu, "
2087 "last ping %lu, now %lu\n",
2088 conn->ping_timeout, conn->recv_timeout,
2089 last_recv, conn->last_ping, jiffies);
2090 spin_unlock(&session->frwd_lock);
2091 iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT);
2092 return;
2093 }
2094
2095 if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2096 /* send a ping to try to provoke some traffic */
2097 ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2098 iscsi_send_nopout(conn, NULL);
2099 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2100 } else
2101 next_timeout = last_recv + recv_timeout;
2102
2103 ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2104 mod_timer(&conn->transport_timer, next_timeout);
2105 done:
2106 spin_unlock(&session->frwd_lock);
2107 }
2108
2109 static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2110 struct iscsi_tm *hdr)
2111 {
2112 memset(hdr, 0, sizeof(*hdr));
2113 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2114 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2115 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2116 hdr->lun = task->lun;
2117 hdr->rtt = task->hdr_itt;
2118 hdr->refcmdsn = task->cmdsn;
2119 }
2120
2121 int iscsi_eh_abort(struct scsi_cmnd *sc)
2122 {
2123 struct iscsi_cls_session *cls_session;
2124 struct iscsi_session *session;
2125 struct iscsi_conn *conn;
2126 struct iscsi_task *task;
2127 struct iscsi_tm *hdr;
2128 int rc, age;
2129
2130 cls_session = starget_to_session(scsi_target(sc->device));
2131 session = cls_session->dd_data;
2132
2133 ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2134
2135 mutex_lock(&session->eh_mutex);
2136 spin_lock_bh(&session->frwd_lock);
2137 /*
2138 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2139 * got the command.
2140 */
2141 if (!sc->SCp.ptr) {
2142 ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2143 "it completed.\n");
2144 spin_unlock_bh(&session->frwd_lock);
2145 mutex_unlock(&session->eh_mutex);
2146 return SUCCESS;
2147 }
2148
2149 /*
2150 * If we are not logged in or we have started a new session
2151 * then let the host reset code handle this
2152 */
2153 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2154 sc->SCp.phase != session->age) {
2155 spin_unlock_bh(&session->frwd_lock);
2156 mutex_unlock(&session->eh_mutex);
2157 ISCSI_DBG_EH(session, "failing abort due to dropped "
2158 "session.\n");
2159 return FAILED;
2160 }
2161
2162 conn = session->leadconn;
2163 conn->eh_abort_cnt++;
2164 age = session->age;
2165
2166 task = (struct iscsi_task *)sc->SCp.ptr;
2167 ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
2168 sc, task->itt);
2169
2170 /* task completed before time out */
2171 if (!task->sc) {
2172 ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2173 goto success;
2174 }
2175
2176 if (task->state == ISCSI_TASK_PENDING) {
2177 fail_scsi_task(task, DID_ABORT);
2178 goto success;
2179 }
2180
2181 /* only have one tmf outstanding at a time */
2182 if (conn->tmf_state != TMF_INITIAL)
2183 goto failed;
2184 conn->tmf_state = TMF_QUEUED;
2185
2186 hdr = &conn->tmhdr;
2187 iscsi_prep_abort_task_pdu(task, hdr);
2188
2189 if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) {
2190 rc = FAILED;
2191 goto failed;
2192 }
2193
2194 switch (conn->tmf_state) {
2195 case TMF_SUCCESS:
2196 spin_unlock_bh(&session->frwd_lock);
2197 /*
2198 * stop tx side incase the target had sent a abort rsp but
2199 * the initiator was still writing out data.
2200 */
2201 iscsi_suspend_tx(conn);
2202 /*
2203 * we do not stop the recv side because targets have been
2204 * good and have never sent us a successful tmf response
2205 * then sent more data for the cmd.
2206 */
2207 spin_lock_bh(&session->frwd_lock);
2208 fail_scsi_task(task, DID_ABORT);
2209 conn->tmf_state = TMF_INITIAL;
2210 memset(hdr, 0, sizeof(*hdr));
2211 spin_unlock_bh(&session->frwd_lock);
2212 iscsi_start_tx(conn);
2213 goto success_unlocked;
2214 case TMF_TIMEDOUT:
2215 spin_unlock_bh(&session->frwd_lock);
2216 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2217 goto failed_unlocked;
2218 case TMF_NOT_FOUND:
2219 if (!sc->SCp.ptr) {
2220 conn->tmf_state = TMF_INITIAL;
2221 memset(hdr, 0, sizeof(*hdr));
2222 /* task completed before tmf abort response */
2223 ISCSI_DBG_EH(session, "sc completed while abort in "
2224 "progress\n");
2225 goto success;
2226 }
2227 /* fall through */
2228 default:
2229 conn->tmf_state = TMF_INITIAL;
2230 goto failed;
2231 }
2232
2233 success:
2234 spin_unlock_bh(&session->frwd_lock);
2235 success_unlocked:
2236 ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2237 sc, task->itt);
2238 mutex_unlock(&session->eh_mutex);
2239 return SUCCESS;
2240
2241 failed:
2242 spin_unlock_bh(&session->frwd_lock);
2243 failed_unlocked:
2244 ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2245 task ? task->itt : 0);
2246 mutex_unlock(&session->eh_mutex);
2247 return FAILED;
2248 }
2249 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2250
2251 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2252 {
2253 memset(hdr, 0, sizeof(*hdr));
2254 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2255 hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2256 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2257 int_to_scsilun(sc->device->lun, &hdr->lun);
2258 hdr->rtt = RESERVED_ITT;
2259 }
2260
2261 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2262 {
2263 struct iscsi_cls_session *cls_session;
2264 struct iscsi_session *session;
2265 struct iscsi_conn *conn;
2266 struct iscsi_tm *hdr;
2267 int rc = FAILED;
2268
2269 cls_session = starget_to_session(scsi_target(sc->device));
2270 session = cls_session->dd_data;
2271
2272 ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc,
2273 sc->device->lun);
2274
2275 mutex_lock(&session->eh_mutex);
2276 spin_lock_bh(&session->frwd_lock);
2277 /*
2278 * Just check if we are not logged in. We cannot check for
2279 * the phase because the reset could come from a ioctl.
2280 */
2281 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2282 goto unlock;
2283 conn = session->leadconn;
2284
2285 /* only have one tmf outstanding at a time */
2286 if (conn->tmf_state != TMF_INITIAL)
2287 goto unlock;
2288 conn->tmf_state = TMF_QUEUED;
2289
2290 hdr = &conn->tmhdr;
2291 iscsi_prep_lun_reset_pdu(sc, hdr);
2292
2293 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2294 session->lu_reset_timeout)) {
2295 rc = FAILED;
2296 goto unlock;
2297 }
2298
2299 switch (conn->tmf_state) {
2300 case TMF_SUCCESS:
2301 break;
2302 case TMF_TIMEDOUT:
2303 spin_unlock_bh(&session->frwd_lock);
2304 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2305 goto done;
2306 default:
2307 conn->tmf_state = TMF_INITIAL;
2308 goto unlock;
2309 }
2310
2311 rc = SUCCESS;
2312 spin_unlock_bh(&session->frwd_lock);
2313
2314 iscsi_suspend_tx(conn);
2315
2316 spin_lock_bh(&session->frwd_lock);
2317 memset(hdr, 0, sizeof(*hdr));
2318 fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2319 conn->tmf_state = TMF_INITIAL;
2320 spin_unlock_bh(&session->frwd_lock);
2321
2322 iscsi_start_tx(conn);
2323 goto done;
2324
2325 unlock:
2326 spin_unlock_bh(&session->frwd_lock);
2327 done:
2328 ISCSI_DBG_EH(session, "dev reset result = %s\n",
2329 rc == SUCCESS ? "SUCCESS" : "FAILED");
2330 mutex_unlock(&session->eh_mutex);
2331 return rc;
2332 }
2333 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2334
2335 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2336 {
2337 struct iscsi_session *session = cls_session->dd_data;
2338
2339 spin_lock_bh(&session->frwd_lock);
2340 if (session->state != ISCSI_STATE_LOGGED_IN) {
2341 session->state = ISCSI_STATE_RECOVERY_FAILED;
2342 if (session->leadconn)
2343 wake_up(&session->leadconn->ehwait);
2344 }
2345 spin_unlock_bh(&session->frwd_lock);
2346 }
2347 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2348
2349 /**
2350 * iscsi_eh_session_reset - drop session and attempt relogin
2351 * @sc: scsi command
2352 *
2353 * This function will wait for a relogin, session termination from
2354 * userspace, or a recovery/replacement timeout.
2355 */
2356 int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2357 {
2358 struct iscsi_cls_session *cls_session;
2359 struct iscsi_session *session;
2360 struct iscsi_conn *conn;
2361
2362 cls_session = starget_to_session(scsi_target(sc->device));
2363 session = cls_session->dd_data;
2364 conn = session->leadconn;
2365
2366 mutex_lock(&session->eh_mutex);
2367 spin_lock_bh(&session->frwd_lock);
2368 if (session->state == ISCSI_STATE_TERMINATE) {
2369 failed:
2370 ISCSI_DBG_EH(session,
2371 "failing session reset: Could not log back into "
2372 "%s, %s [age %d]\n", session->targetname,
2373 conn->persistent_address, session->age);
2374 spin_unlock_bh(&session->frwd_lock);
2375 mutex_unlock(&session->eh_mutex);
2376 return FAILED;
2377 }
2378
2379 spin_unlock_bh(&session->frwd_lock);
2380 mutex_unlock(&session->eh_mutex);
2381 /*
2382 * we drop the lock here but the leadconn cannot be destoyed while
2383 * we are in the scsi eh
2384 */
2385 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2386
2387 ISCSI_DBG_EH(session, "wait for relogin\n");
2388 wait_event_interruptible(conn->ehwait,
2389 session->state == ISCSI_STATE_TERMINATE ||
2390 session->state == ISCSI_STATE_LOGGED_IN ||
2391 session->state == ISCSI_STATE_RECOVERY_FAILED);
2392 if (signal_pending(current))
2393 flush_signals(current);
2394
2395 mutex_lock(&session->eh_mutex);
2396 spin_lock_bh(&session->frwd_lock);
2397 if (session->state == ISCSI_STATE_LOGGED_IN) {
2398 ISCSI_DBG_EH(session,
2399 "session reset succeeded for %s,%s\n",
2400 session->targetname, conn->persistent_address);
2401 } else
2402 goto failed;
2403 spin_unlock_bh(&session->frwd_lock);
2404 mutex_unlock(&session->eh_mutex);
2405 return SUCCESS;
2406 }
2407 EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2408
2409 static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2410 {
2411 memset(hdr, 0, sizeof(*hdr));
2412 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2413 hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2414 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2415 hdr->rtt = RESERVED_ITT;
2416 }
2417
2418 /**
2419 * iscsi_eh_target_reset - reset target
2420 * @sc: scsi command
2421 *
2422 * This will attempt to send a warm target reset.
2423 */
2424 int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2425 {
2426 struct iscsi_cls_session *cls_session;
2427 struct iscsi_session *session;
2428 struct iscsi_conn *conn;
2429 struct iscsi_tm *hdr;
2430 int rc = FAILED;
2431
2432 cls_session = starget_to_session(scsi_target(sc->device));
2433 session = cls_session->dd_data;
2434
2435 ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2436 session->targetname);
2437
2438 mutex_lock(&session->eh_mutex);
2439 spin_lock_bh(&session->frwd_lock);
2440 /*
2441 * Just check if we are not logged in. We cannot check for
2442 * the phase because the reset could come from a ioctl.
2443 */
2444 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2445 goto unlock;
2446 conn = session->leadconn;
2447
2448 /* only have one tmf outstanding at a time */
2449 if (conn->tmf_state != TMF_INITIAL)
2450 goto unlock;
2451 conn->tmf_state = TMF_QUEUED;
2452
2453 hdr = &conn->tmhdr;
2454 iscsi_prep_tgt_reset_pdu(sc, hdr);
2455
2456 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2457 session->tgt_reset_timeout)) {
2458 rc = FAILED;
2459 goto unlock;
2460 }
2461
2462 switch (conn->tmf_state) {
2463 case TMF_SUCCESS:
2464 break;
2465 case TMF_TIMEDOUT:
2466 spin_unlock_bh(&session->frwd_lock);
2467 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2468 goto done;
2469 default:
2470 conn->tmf_state = TMF_INITIAL;
2471 goto unlock;
2472 }
2473
2474 rc = SUCCESS;
2475 spin_unlock_bh(&session->frwd_lock);
2476
2477 iscsi_suspend_tx(conn);
2478
2479 spin_lock_bh(&session->frwd_lock);
2480 memset(hdr, 0, sizeof(*hdr));
2481 fail_scsi_tasks(conn, -1, DID_ERROR);
2482 conn->tmf_state = TMF_INITIAL;
2483 spin_unlock_bh(&session->frwd_lock);
2484
2485 iscsi_start_tx(conn);
2486 goto done;
2487
2488 unlock:
2489 spin_unlock_bh(&session->frwd_lock);
2490 done:
2491 ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2492 rc == SUCCESS ? "SUCCESS" : "FAILED");
2493 mutex_unlock(&session->eh_mutex);
2494 return rc;
2495 }
2496 EXPORT_SYMBOL_GPL(iscsi_eh_target_reset);
2497
2498 /**
2499 * iscsi_eh_recover_target - reset target and possibly the session
2500 * @sc: scsi command
2501 *
2502 * This will attempt to send a warm target reset. If that fails,
2503 * we will escalate to ERL0 session recovery.
2504 */
2505 int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2506 {
2507 int rc;
2508
2509 rc = iscsi_eh_target_reset(sc);
2510 if (rc == FAILED)
2511 rc = iscsi_eh_session_reset(sc);
2512 return rc;
2513 }
2514 EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2515
2516 /*
2517 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2518 * should be accessed via kfifo_{get,put} on q->queue.
2519 * Optionally, the caller can obtain the array of object pointers
2520 * by passing in a non-NULL @items pointer
2521 */
2522 int
2523 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2524 {
2525 int i, num_arrays = 1;
2526
2527 memset(q, 0, sizeof(*q));
2528
2529 q->max = max;
2530
2531 /* If the user passed an items pointer, he wants a copy of
2532 * the array. */
2533 if (items)
2534 num_arrays++;
2535 q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
2536 if (q->pool == NULL)
2537 return -ENOMEM;
2538
2539 kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2540
2541 for (i = 0; i < max; i++) {
2542 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2543 if (q->pool[i] == NULL) {
2544 q->max = i;
2545 goto enomem;
2546 }
2547 kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2548 }
2549
2550 if (items) {
2551 *items = q->pool + max;
2552 memcpy(*items, q->pool, max * sizeof(void *));
2553 }
2554
2555 return 0;
2556
2557 enomem:
2558 iscsi_pool_free(q);
2559 return -ENOMEM;
2560 }
2561 EXPORT_SYMBOL_GPL(iscsi_pool_init);
2562
2563 void iscsi_pool_free(struct iscsi_pool *q)
2564 {
2565 int i;
2566
2567 for (i = 0; i < q->max; i++)
2568 kfree(q->pool[i]);
2569 kfree(q->pool);
2570 }
2571 EXPORT_SYMBOL_GPL(iscsi_pool_free);
2572
2573 /**
2574 * iscsi_host_add - add host to system
2575 * @shost: scsi host
2576 * @pdev: parent device
2577 *
2578 * This should be called by partial offload and software iscsi drivers
2579 * to add a host to the system.
2580 */
2581 int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2582 {
2583 if (!shost->can_queue)
2584 shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2585
2586 if (!shost->cmd_per_lun)
2587 shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2588
2589 if (!shost->transportt->eh_timed_out)
2590 shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
2591 return scsi_add_host(shost, pdev);
2592 }
2593 EXPORT_SYMBOL_GPL(iscsi_host_add);
2594
2595 /**
2596 * iscsi_host_alloc - allocate a host and driver data
2597 * @sht: scsi host template
2598 * @dd_data_size: driver host data size
2599 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2600 *
2601 * This should be called by partial offload and software iscsi drivers.
2602 * To access the driver specific memory use the iscsi_host_priv() macro.
2603 */
2604 struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2605 int dd_data_size, bool xmit_can_sleep)
2606 {
2607 struct Scsi_Host *shost;
2608 struct iscsi_host *ihost;
2609
2610 shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2611 if (!shost)
2612 return NULL;
2613 ihost = shost_priv(shost);
2614
2615 if (xmit_can_sleep) {
2616 snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2617 "iscsi_q_%d", shost->host_no);
2618 ihost->workq = create_singlethread_workqueue(ihost->workq_name);
2619 if (!ihost->workq)
2620 goto free_host;
2621 }
2622
2623 spin_lock_init(&ihost->lock);
2624 ihost->state = ISCSI_HOST_SETUP;
2625 ihost->num_sessions = 0;
2626 init_waitqueue_head(&ihost->session_removal_wq);
2627 return shost;
2628
2629 free_host:
2630 scsi_host_put(shost);
2631 return NULL;
2632 }
2633 EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2634
2635 static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2636 {
2637 iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2638 }
2639
2640 /**
2641 * iscsi_host_remove - remove host and sessions
2642 * @shost: scsi host
2643 *
2644 * If there are any sessions left, this will initiate the removal and wait
2645 * for the completion.
2646 */
2647 void iscsi_host_remove(struct Scsi_Host *shost)
2648 {
2649 struct iscsi_host *ihost = shost_priv(shost);
2650 unsigned long flags;
2651
2652 spin_lock_irqsave(&ihost->lock, flags);
2653 ihost->state = ISCSI_HOST_REMOVED;
2654 spin_unlock_irqrestore(&ihost->lock, flags);
2655
2656 iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2657 wait_event_interruptible(ihost->session_removal_wq,
2658 ihost->num_sessions == 0);
2659 if (signal_pending(current))
2660 flush_signals(current);
2661
2662 scsi_remove_host(shost);
2663 if (ihost->workq)
2664 destroy_workqueue(ihost->workq);
2665 }
2666 EXPORT_SYMBOL_GPL(iscsi_host_remove);
2667
2668 void iscsi_host_free(struct Scsi_Host *shost)
2669 {
2670 struct iscsi_host *ihost = shost_priv(shost);
2671
2672 kfree(ihost->netdev);
2673 kfree(ihost->hwaddress);
2674 kfree(ihost->initiatorname);
2675 scsi_host_put(shost);
2676 }
2677 EXPORT_SYMBOL_GPL(iscsi_host_free);
2678
2679 static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2680 {
2681 struct iscsi_host *ihost = shost_priv(shost);
2682 unsigned long flags;
2683
2684 shost = scsi_host_get(shost);
2685 if (!shost) {
2686 printk(KERN_ERR "Invalid state. Cannot notify host removal "
2687 "of session teardown event because host already "
2688 "removed.\n");
2689 return;
2690 }
2691
2692 spin_lock_irqsave(&ihost->lock, flags);
2693 ihost->num_sessions--;
2694 if (ihost->num_sessions == 0)
2695 wake_up(&ihost->session_removal_wq);
2696 spin_unlock_irqrestore(&ihost->lock, flags);
2697 scsi_host_put(shost);
2698 }
2699
2700 /**
2701 * iscsi_session_setup - create iscsi cls session and host and session
2702 * @iscsit: iscsi transport template
2703 * @shost: scsi host
2704 * @cmds_max: session can queue
2705 * @cmd_task_size: LLD task private data size
2706 * @initial_cmdsn: initial CmdSN
2707 *
2708 * This can be used by software iscsi_transports that allocate
2709 * a session per scsi host.
2710 *
2711 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2712 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2713 * for nop handling and login/logout requests.
2714 */
2715 struct iscsi_cls_session *
2716 iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2717 uint16_t cmds_max, int dd_size, int cmd_task_size,
2718 uint32_t initial_cmdsn, unsigned int id)
2719 {
2720 struct iscsi_host *ihost = shost_priv(shost);
2721 struct iscsi_session *session;
2722 struct iscsi_cls_session *cls_session;
2723 int cmd_i, scsi_cmds, total_cmds = cmds_max;
2724 unsigned long flags;
2725
2726 spin_lock_irqsave(&ihost->lock, flags);
2727 if (ihost->state == ISCSI_HOST_REMOVED) {
2728 spin_unlock_irqrestore(&ihost->lock, flags);
2729 return NULL;
2730 }
2731 ihost->num_sessions++;
2732 spin_unlock_irqrestore(&ihost->lock, flags);
2733
2734 if (!total_cmds)
2735 total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2736 /*
2737 * The iscsi layer needs some tasks for nop handling and tmfs,
2738 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2739 * + 1 command for scsi IO.
2740 */
2741 if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2742 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2743 "must be a power of two that is at least %d.\n",
2744 total_cmds, ISCSI_TOTAL_CMDS_MIN);
2745 goto dec_session_count;
2746 }
2747
2748 if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2749 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2750 "must be a power of 2 less than or equal to %d.\n",
2751 cmds_max, ISCSI_TOTAL_CMDS_MAX);
2752 total_cmds = ISCSI_TOTAL_CMDS_MAX;
2753 }
2754
2755 if (!is_power_of_2(total_cmds)) {
2756 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2757 "must be a power of 2.\n", total_cmds);
2758 total_cmds = rounddown_pow_of_two(total_cmds);
2759 if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
2760 return NULL;
2761 printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
2762 total_cmds);
2763 }
2764 scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2765
2766 cls_session = iscsi_alloc_session(shost, iscsit,
2767 sizeof(struct iscsi_session) +
2768 dd_size);
2769 if (!cls_session)
2770 goto dec_session_count;
2771 session = cls_session->dd_data;
2772 session->cls_session = cls_session;
2773 session->host = shost;
2774 session->state = ISCSI_STATE_FREE;
2775 session->fast_abort = 1;
2776 session->tgt_reset_timeout = 30;
2777 session->lu_reset_timeout = 15;
2778 session->abort_timeout = 10;
2779 session->scsi_cmds_max = scsi_cmds;
2780 session->cmds_max = total_cmds;
2781 session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2782 session->exp_cmdsn = initial_cmdsn + 1;
2783 session->max_cmdsn = initial_cmdsn + 1;
2784 session->max_r2t = 1;
2785 session->tt = iscsit;
2786 session->dd_data = cls_session->dd_data + sizeof(*session);
2787
2788 mutex_init(&session->eh_mutex);
2789 spin_lock_init(&session->frwd_lock);
2790 spin_lock_init(&session->back_lock);
2791
2792 /* initialize SCSI PDU commands pool */
2793 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2794 (void***)&session->cmds,
2795 cmd_task_size + sizeof(struct iscsi_task)))
2796 goto cmdpool_alloc_fail;
2797
2798 /* pre-format cmds pool with ITT */
2799 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2800 struct iscsi_task *task = session->cmds[cmd_i];
2801
2802 if (cmd_task_size)
2803 task->dd_data = &task[1];
2804 task->itt = cmd_i;
2805 task->state = ISCSI_TASK_FREE;
2806 INIT_LIST_HEAD(&task->running);
2807 }
2808
2809 if (!try_module_get(iscsit->owner))
2810 goto module_get_fail;
2811
2812 if (iscsi_add_session(cls_session, id))
2813 goto cls_session_fail;
2814
2815 return cls_session;
2816
2817 cls_session_fail:
2818 module_put(iscsit->owner);
2819 module_get_fail:
2820 iscsi_pool_free(&session->cmdpool);
2821 cmdpool_alloc_fail:
2822 iscsi_free_session(cls_session);
2823 dec_session_count:
2824 iscsi_host_dec_session_cnt(shost);
2825 return NULL;
2826 }
2827 EXPORT_SYMBOL_GPL(iscsi_session_setup);
2828
2829 /**
2830 * iscsi_session_teardown - destroy session, host, and cls_session
2831 * @cls_session: iscsi session
2832 *
2833 * The driver must have called iscsi_remove_session before
2834 * calling this.
2835 */
2836 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2837 {
2838 struct iscsi_session *session = cls_session->dd_data;
2839 struct module *owner = cls_session->transport->owner;
2840 struct Scsi_Host *shost = session->host;
2841
2842 iscsi_pool_free(&session->cmdpool);
2843
2844 kfree(session->password);
2845 kfree(session->password_in);
2846 kfree(session->username);
2847 kfree(session->username_in);
2848 kfree(session->targetname);
2849 kfree(session->targetalias);
2850 kfree(session->initiatorname);
2851 kfree(session->boot_root);
2852 kfree(session->boot_nic);
2853 kfree(session->boot_target);
2854 kfree(session->ifacename);
2855 kfree(session->portal_type);
2856 kfree(session->discovery_parent_type);
2857
2858 iscsi_destroy_session(cls_session);
2859 iscsi_host_dec_session_cnt(shost);
2860 module_put(owner);
2861 }
2862 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
2863
2864 /**
2865 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
2866 * @cls_session: iscsi_cls_session
2867 * @dd_size: private driver data size
2868 * @conn_idx: cid
2869 */
2870 struct iscsi_cls_conn *
2871 iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2872 uint32_t conn_idx)
2873 {
2874 struct iscsi_session *session = cls_session->dd_data;
2875 struct iscsi_conn *conn;
2876 struct iscsi_cls_conn *cls_conn;
2877 char *data;
2878
2879 cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2880 conn_idx);
2881 if (!cls_conn)
2882 return NULL;
2883 conn = cls_conn->dd_data;
2884 memset(conn, 0, sizeof(*conn) + dd_size);
2885
2886 conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2887 conn->session = session;
2888 conn->cls_conn = cls_conn;
2889 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2890 conn->id = conn_idx;
2891 conn->exp_statsn = 0;
2892 conn->tmf_state = TMF_INITIAL;
2893
2894 init_timer(&conn->transport_timer);
2895 conn->transport_timer.data = (unsigned long)conn;
2896 conn->transport_timer.function = iscsi_check_transport_timeouts;
2897
2898 INIT_LIST_HEAD(&conn->mgmtqueue);
2899 INIT_LIST_HEAD(&conn->cmdqueue);
2900 INIT_LIST_HEAD(&conn->requeue);
2901 INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2902
2903 /* allocate login_task used for the login/text sequences */
2904 spin_lock_bh(&session->frwd_lock);
2905 if (!kfifo_out(&session->cmdpool.queue,
2906 (void*)&conn->login_task,
2907 sizeof(void*))) {
2908 spin_unlock_bh(&session->frwd_lock);
2909 goto login_task_alloc_fail;
2910 }
2911 spin_unlock_bh(&session->frwd_lock);
2912
2913 data = (char *) __get_free_pages(GFP_KERNEL,
2914 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2915 if (!data)
2916 goto login_task_data_alloc_fail;
2917 conn->login_task->data = conn->data = data;
2918
2919 init_timer(&conn->tmf_timer);
2920 init_waitqueue_head(&conn->ehwait);
2921
2922 return cls_conn;
2923
2924 login_task_data_alloc_fail:
2925 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2926 sizeof(void*));
2927 login_task_alloc_fail:
2928 iscsi_destroy_conn(cls_conn);
2929 return NULL;
2930 }
2931 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2932
2933 /**
2934 * iscsi_conn_teardown - teardown iscsi connection
2935 * cls_conn: iscsi class connection
2936 *
2937 * TODO: we may need to make this into a two step process
2938 * like scsi-mls remove + put host
2939 */
2940 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2941 {
2942 struct iscsi_conn *conn = cls_conn->dd_data;
2943 struct iscsi_session *session = conn->session;
2944 unsigned long flags;
2945
2946 del_timer_sync(&conn->transport_timer);
2947
2948 spin_lock_bh(&session->frwd_lock);
2949 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2950 if (session->leadconn == conn) {
2951 /*
2952 * leading connection? then give up on recovery.
2953 */
2954 session->state = ISCSI_STATE_TERMINATE;
2955 wake_up(&conn->ehwait);
2956 }
2957 spin_unlock_bh(&session->frwd_lock);
2958
2959 /*
2960 * Block until all in-progress commands for this connection
2961 * time out or fail.
2962 */
2963 for (;;) {
2964 spin_lock_irqsave(session->host->host_lock, flags);
2965 if (!atomic_read(&session->host->host_busy)) { /* OK for ERL == 0 */
2966 spin_unlock_irqrestore(session->host->host_lock, flags);
2967 break;
2968 }
2969 spin_unlock_irqrestore(session->host->host_lock, flags);
2970 msleep_interruptible(500);
2971 iscsi_conn_printk(KERN_INFO, conn, "iscsi conn_destroy(): "
2972 "host_busy %d host_failed %d\n",
2973 atomic_read(&session->host->host_busy),
2974 session->host->host_failed);
2975 /*
2976 * force eh_abort() to unblock
2977 */
2978 wake_up(&conn->ehwait);
2979 }
2980
2981 /* flush queued up work because we free the connection below */
2982 iscsi_suspend_tx(conn);
2983
2984 spin_lock_bh(&session->frwd_lock);
2985 free_pages((unsigned long) conn->data,
2986 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2987 kfree(conn->persistent_address);
2988 kfree(conn->local_ipaddr);
2989 /* regular RX path uses back_lock */
2990 spin_lock_bh(&session->back_lock);
2991 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2992 sizeof(void*));
2993 spin_unlock_bh(&session->back_lock);
2994 if (session->leadconn == conn)
2995 session->leadconn = NULL;
2996 spin_unlock_bh(&session->frwd_lock);
2997
2998 iscsi_destroy_conn(cls_conn);
2999 }
3000 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
3001
3002 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
3003 {
3004 struct iscsi_conn *conn = cls_conn->dd_data;
3005 struct iscsi_session *session = conn->session;
3006
3007 if (!session) {
3008 iscsi_conn_printk(KERN_ERR, conn,
3009 "can't start unbound connection\n");
3010 return -EPERM;
3011 }
3012
3013 if ((session->imm_data_en || !session->initial_r2t_en) &&
3014 session->first_burst > session->max_burst) {
3015 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
3016 "first_burst %d max_burst %d\n",
3017 session->first_burst, session->max_burst);
3018 return -EINVAL;
3019 }
3020
3021 if (conn->ping_timeout && !conn->recv_timeout) {
3022 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
3023 "zero. Using 5 seconds\n.");
3024 conn->recv_timeout = 5;
3025 }
3026
3027 if (conn->recv_timeout && !conn->ping_timeout) {
3028 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
3029 "zero. Using 5 seconds.\n");
3030 conn->ping_timeout = 5;
3031 }
3032
3033 spin_lock_bh(&session->frwd_lock);
3034 conn->c_stage = ISCSI_CONN_STARTED;
3035 session->state = ISCSI_STATE_LOGGED_IN;
3036 session->queued_cmdsn = session->cmdsn;
3037
3038 conn->last_recv = jiffies;
3039 conn->last_ping = jiffies;
3040 if (conn->recv_timeout && conn->ping_timeout)
3041 mod_timer(&conn->transport_timer,
3042 jiffies + (conn->recv_timeout * HZ));
3043
3044 switch(conn->stop_stage) {
3045 case STOP_CONN_RECOVER:
3046 /*
3047 * unblock eh_abort() if it is blocked. re-try all
3048 * commands after successful recovery
3049 */
3050 conn->stop_stage = 0;
3051 conn->tmf_state = TMF_INITIAL;
3052 session->age++;
3053 if (session->age == 16)
3054 session->age = 0;
3055 break;
3056 case STOP_CONN_TERM:
3057 conn->stop_stage = 0;
3058 break;
3059 default:
3060 break;
3061 }
3062 spin_unlock_bh(&session->frwd_lock);
3063
3064 iscsi_unblock_session(session->cls_session);
3065 wake_up(&conn->ehwait);
3066 return 0;
3067 }
3068 EXPORT_SYMBOL_GPL(iscsi_conn_start);
3069
3070 static void
3071 fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3072 {
3073 struct iscsi_task *task;
3074 int i, state;
3075
3076 for (i = 0; i < conn->session->cmds_max; i++) {
3077 task = conn->session->cmds[i];
3078 if (task->sc)
3079 continue;
3080
3081 if (task->state == ISCSI_TASK_FREE)
3082 continue;
3083
3084 ISCSI_DBG_SESSION(conn->session,
3085 "failing mgmt itt 0x%x state %d\n",
3086 task->itt, task->state);
3087 state = ISCSI_TASK_ABRT_SESS_RECOV;
3088 if (task->state == ISCSI_TASK_PENDING)
3089 state = ISCSI_TASK_COMPLETED;
3090 iscsi_complete_task(task, state);
3091
3092 }
3093 }
3094
3095 static void iscsi_start_session_recovery(struct iscsi_session *session,
3096 struct iscsi_conn *conn, int flag)
3097 {
3098 int old_stop_stage;
3099
3100 mutex_lock(&session->eh_mutex);
3101 spin_lock_bh(&session->frwd_lock);
3102 if (conn->stop_stage == STOP_CONN_TERM) {
3103 spin_unlock_bh(&session->frwd_lock);
3104 mutex_unlock(&session->eh_mutex);
3105 return;
3106 }
3107
3108 /*
3109 * When this is called for the in_login state, we only want to clean
3110 * up the login task and connection. We do not need to block and set
3111 * the recovery state again
3112 */
3113 if (flag == STOP_CONN_TERM)
3114 session->state = ISCSI_STATE_TERMINATE;
3115 else if (conn->stop_stage != STOP_CONN_RECOVER)
3116 session->state = ISCSI_STATE_IN_RECOVERY;
3117
3118 old_stop_stage = conn->stop_stage;
3119 conn->stop_stage = flag;
3120 spin_unlock_bh(&session->frwd_lock);
3121
3122 del_timer_sync(&conn->transport_timer);
3123 iscsi_suspend_tx(conn);
3124
3125 spin_lock_bh(&session->frwd_lock);
3126 conn->c_stage = ISCSI_CONN_STOPPED;
3127 spin_unlock_bh(&session->frwd_lock);
3128
3129 /*
3130 * for connection level recovery we should not calculate
3131 * header digest. conn->hdr_size used for optimization
3132 * in hdr_extract() and will be re-negotiated at
3133 * set_param() time.
3134 */
3135 if (flag == STOP_CONN_RECOVER) {
3136 conn->hdrdgst_en = 0;
3137 conn->datadgst_en = 0;
3138 if (session->state == ISCSI_STATE_IN_RECOVERY &&
3139 old_stop_stage != STOP_CONN_RECOVER) {
3140 ISCSI_DBG_SESSION(session, "blocking session\n");
3141 iscsi_block_session(session->cls_session);
3142 }
3143 }
3144
3145 /*
3146 * flush queues.
3147 */
3148 spin_lock_bh(&session->frwd_lock);
3149 fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3150 fail_mgmt_tasks(session, conn);
3151 memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
3152 spin_unlock_bh(&session->frwd_lock);
3153 mutex_unlock(&session->eh_mutex);
3154 }
3155
3156 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3157 {
3158 struct iscsi_conn *conn = cls_conn->dd_data;
3159 struct iscsi_session *session = conn->session;
3160
3161 switch (flag) {
3162 case STOP_CONN_RECOVER:
3163 case STOP_CONN_TERM:
3164 iscsi_start_session_recovery(session, conn, flag);
3165 break;
3166 default:
3167 iscsi_conn_printk(KERN_ERR, conn,
3168 "invalid stop flag %d\n", flag);
3169 }
3170 }
3171 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3172
3173 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3174 struct iscsi_cls_conn *cls_conn, int is_leading)
3175 {
3176 struct iscsi_session *session = cls_session->dd_data;
3177 struct iscsi_conn *conn = cls_conn->dd_data;
3178
3179 spin_lock_bh(&session->frwd_lock);
3180 if (is_leading)
3181 session->leadconn = conn;
3182 spin_unlock_bh(&session->frwd_lock);
3183
3184 /*
3185 * Unblock xmitworker(), Login Phase will pass through.
3186 */
3187 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3188 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3189 return 0;
3190 }
3191 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3192
3193 int iscsi_switch_str_param(char **param, char *new_val_buf)
3194 {
3195 char *new_val;
3196
3197 if (*param) {
3198 if (!strcmp(*param, new_val_buf))
3199 return 0;
3200 }
3201
3202 new_val = kstrdup(new_val_buf, GFP_NOIO);
3203 if (!new_val)
3204 return -ENOMEM;
3205
3206 kfree(*param);
3207 *param = new_val;
3208 return 0;
3209 }
3210 EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3211
3212 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3213 enum iscsi_param param, char *buf, int buflen)
3214 {
3215 struct iscsi_conn *conn = cls_conn->dd_data;
3216 struct iscsi_session *session = conn->session;
3217 int val;
3218
3219 switch(param) {
3220 case ISCSI_PARAM_FAST_ABORT:
3221 sscanf(buf, "%d", &session->fast_abort);
3222 break;
3223 case ISCSI_PARAM_ABORT_TMO:
3224 sscanf(buf, "%d", &session->abort_timeout);
3225 break;
3226 case ISCSI_PARAM_LU_RESET_TMO:
3227 sscanf(buf, "%d", &session->lu_reset_timeout);
3228 break;
3229 case ISCSI_PARAM_TGT_RESET_TMO:
3230 sscanf(buf, "%d", &session->tgt_reset_timeout);
3231 break;
3232 case ISCSI_PARAM_PING_TMO:
3233 sscanf(buf, "%d", &conn->ping_timeout);
3234 break;
3235 case ISCSI_PARAM_RECV_TMO:
3236 sscanf(buf, "%d", &conn->recv_timeout);
3237 break;
3238 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3239 sscanf(buf, "%d", &conn->max_recv_dlength);
3240 break;
3241 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3242 sscanf(buf, "%d", &conn->max_xmit_dlength);
3243 break;
3244 case ISCSI_PARAM_HDRDGST_EN:
3245 sscanf(buf, "%d", &conn->hdrdgst_en);
3246 break;
3247 case ISCSI_PARAM_DATADGST_EN:
3248 sscanf(buf, "%d", &conn->datadgst_en);
3249 break;
3250 case ISCSI_PARAM_INITIAL_R2T_EN:
3251 sscanf(buf, "%d", &session->initial_r2t_en);
3252 break;
3253 case ISCSI_PARAM_MAX_R2T:
3254 sscanf(buf, "%hu", &session->max_r2t);
3255 break;
3256 case ISCSI_PARAM_IMM_DATA_EN:
3257 sscanf(buf, "%d", &session->imm_data_en);
3258 break;
3259 case ISCSI_PARAM_FIRST_BURST:
3260 sscanf(buf, "%d", &session->first_burst);
3261 break;
3262 case ISCSI_PARAM_MAX_BURST:
3263 sscanf(buf, "%d", &session->max_burst);
3264 break;
3265 case ISCSI_PARAM_PDU_INORDER_EN:
3266 sscanf(buf, "%d", &session->pdu_inorder_en);
3267 break;
3268 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3269 sscanf(buf, "%d", &session->dataseq_inorder_en);
3270 break;
3271 case ISCSI_PARAM_ERL:
3272 sscanf(buf, "%d", &session->erl);
3273 break;
3274 case ISCSI_PARAM_EXP_STATSN:
3275 sscanf(buf, "%u", &conn->exp_statsn);
3276 break;
3277 case ISCSI_PARAM_USERNAME:
3278 return iscsi_switch_str_param(&session->username, buf);
3279 case ISCSI_PARAM_USERNAME_IN:
3280 return iscsi_switch_str_param(&session->username_in, buf);
3281 case ISCSI_PARAM_PASSWORD:
3282 return iscsi_switch_str_param(&session->password, buf);
3283 case ISCSI_PARAM_PASSWORD_IN:
3284 return iscsi_switch_str_param(&session->password_in, buf);
3285 case ISCSI_PARAM_TARGET_NAME:
3286 return iscsi_switch_str_param(&session->targetname, buf);
3287 case ISCSI_PARAM_TARGET_ALIAS:
3288 return iscsi_switch_str_param(&session->targetalias, buf);
3289 case ISCSI_PARAM_TPGT:
3290 sscanf(buf, "%d", &session->tpgt);
3291 break;
3292 case ISCSI_PARAM_PERSISTENT_PORT:
3293 sscanf(buf, "%d", &conn->persistent_port);
3294 break;
3295 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3296 return iscsi_switch_str_param(&conn->persistent_address, buf);
3297 case ISCSI_PARAM_IFACE_NAME:
3298 return iscsi_switch_str_param(&session->ifacename, buf);
3299 case ISCSI_PARAM_INITIATOR_NAME:
3300 return iscsi_switch_str_param(&session->initiatorname, buf);
3301 case ISCSI_PARAM_BOOT_ROOT:
3302 return iscsi_switch_str_param(&session->boot_root, buf);
3303 case ISCSI_PARAM_BOOT_NIC:
3304 return iscsi_switch_str_param(&session->boot_nic, buf);
3305 case ISCSI_PARAM_BOOT_TARGET:
3306 return iscsi_switch_str_param(&session->boot_target, buf);
3307 case ISCSI_PARAM_PORTAL_TYPE:
3308 return iscsi_switch_str_param(&session->portal_type, buf);
3309 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3310 return iscsi_switch_str_param(&session->discovery_parent_type,
3311 buf);
3312 case ISCSI_PARAM_DISCOVERY_SESS:
3313 sscanf(buf, "%d", &val);
3314 session->discovery_sess = !!val;
3315 break;
3316 case ISCSI_PARAM_LOCAL_IPADDR:
3317 return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3318 default:
3319 return -ENOSYS;
3320 }
3321
3322 return 0;
3323 }
3324 EXPORT_SYMBOL_GPL(iscsi_set_param);
3325
3326 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3327 enum iscsi_param param, char *buf)
3328 {
3329 struct iscsi_session *session = cls_session->dd_data;
3330 int len;
3331
3332 switch(param) {
3333 case ISCSI_PARAM_FAST_ABORT:
3334 len = sprintf(buf, "%d\n", session->fast_abort);
3335 break;
3336 case ISCSI_PARAM_ABORT_TMO:
3337 len = sprintf(buf, "%d\n", session->abort_timeout);
3338 break;
3339 case ISCSI_PARAM_LU_RESET_TMO:
3340 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
3341 break;
3342 case ISCSI_PARAM_TGT_RESET_TMO:
3343 len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
3344 break;
3345 case ISCSI_PARAM_INITIAL_R2T_EN:
3346 len = sprintf(buf, "%d\n", session->initial_r2t_en);
3347 break;
3348 case ISCSI_PARAM_MAX_R2T:
3349 len = sprintf(buf, "%hu\n", session->max_r2t);
3350 break;
3351 case ISCSI_PARAM_IMM_DATA_EN:
3352 len = sprintf(buf, "%d\n", session->imm_data_en);
3353 break;
3354 case ISCSI_PARAM_FIRST_BURST:
3355 len = sprintf(buf, "%u\n", session->first_burst);
3356 break;
3357 case ISCSI_PARAM_MAX_BURST:
3358 len = sprintf(buf, "%u\n", session->max_burst);
3359 break;
3360 case ISCSI_PARAM_PDU_INORDER_EN:
3361 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
3362 break;
3363 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3364 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
3365 break;
3366 case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3367 len = sprintf(buf, "%d\n", session->def_taskmgmt_tmo);
3368 break;
3369 case ISCSI_PARAM_ERL:
3370 len = sprintf(buf, "%d\n", session->erl);
3371 break;
3372 case ISCSI_PARAM_TARGET_NAME:
3373 len = sprintf(buf, "%s\n", session->targetname);
3374 break;
3375 case ISCSI_PARAM_TARGET_ALIAS:
3376 len = sprintf(buf, "%s\n", session->targetalias);
3377 break;
3378 case ISCSI_PARAM_TPGT:
3379 len = sprintf(buf, "%d\n", session->tpgt);
3380 break;
3381 case ISCSI_PARAM_USERNAME:
3382 len = sprintf(buf, "%s\n", session->username);
3383 break;
3384 case ISCSI_PARAM_USERNAME_IN:
3385 len = sprintf(buf, "%s\n", session->username_in);
3386 break;
3387 case ISCSI_PARAM_PASSWORD:
3388 len = sprintf(buf, "%s\n", session->password);
3389 break;
3390 case ISCSI_PARAM_PASSWORD_IN:
3391 len = sprintf(buf, "%s\n", session->password_in);
3392 break;
3393 case ISCSI_PARAM_IFACE_NAME:
3394 len = sprintf(buf, "%s\n", session->ifacename);
3395 break;
3396 case ISCSI_PARAM_INITIATOR_NAME:
3397 len = sprintf(buf, "%s\n", session->initiatorname);
3398 break;
3399 case ISCSI_PARAM_BOOT_ROOT:
3400 len = sprintf(buf, "%s\n", session->boot_root);
3401 break;
3402 case ISCSI_PARAM_BOOT_NIC:
3403 len = sprintf(buf, "%s\n", session->boot_nic);
3404 break;
3405 case ISCSI_PARAM_BOOT_TARGET:
3406 len = sprintf(buf, "%s\n", session->boot_target);
3407 break;
3408 case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3409 len = sprintf(buf, "%u\n", session->auto_snd_tgt_disable);
3410 break;
3411 case ISCSI_PARAM_DISCOVERY_SESS:
3412 len = sprintf(buf, "%u\n", session->discovery_sess);
3413 break;
3414 case ISCSI_PARAM_PORTAL_TYPE:
3415 len = sprintf(buf, "%s\n", session->portal_type);
3416 break;
3417 case ISCSI_PARAM_CHAP_AUTH_EN:
3418 len = sprintf(buf, "%u\n", session->chap_auth_en);
3419 break;
3420 case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3421 len = sprintf(buf, "%u\n", session->discovery_logout_en);
3422 break;
3423 case ISCSI_PARAM_BIDI_CHAP_EN:
3424 len = sprintf(buf, "%u\n", session->bidi_chap_en);
3425 break;
3426 case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3427 len = sprintf(buf, "%u\n", session->discovery_auth_optional);
3428 break;
3429 case ISCSI_PARAM_DEF_TIME2WAIT:
3430 len = sprintf(buf, "%d\n", session->time2wait);
3431 break;
3432 case ISCSI_PARAM_DEF_TIME2RETAIN:
3433 len = sprintf(buf, "%d\n", session->time2retain);
3434 break;
3435 case ISCSI_PARAM_TSID:
3436 len = sprintf(buf, "%u\n", session->tsid);
3437 break;
3438 case ISCSI_PARAM_ISID:
3439 len = sprintf(buf, "%02x%02x%02x%02x%02x%02x\n",
3440 session->isid[0], session->isid[1],
3441 session->isid[2], session->isid[3],
3442 session->isid[4], session->isid[5]);
3443 break;
3444 case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3445 len = sprintf(buf, "%u\n", session->discovery_parent_idx);
3446 break;
3447 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3448 if (session->discovery_parent_type)
3449 len = sprintf(buf, "%s\n",
3450 session->discovery_parent_type);
3451 else
3452 len = sprintf(buf, "\n");
3453 break;
3454 default:
3455 return -ENOSYS;
3456 }
3457
3458 return len;
3459 }
3460 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3461
3462 int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3463 enum iscsi_param param, char *buf)
3464 {
3465 struct sockaddr_in6 *sin6 = NULL;
3466 struct sockaddr_in *sin = NULL;
3467 int len;
3468
3469 switch (addr->ss_family) {
3470 case AF_INET:
3471 sin = (struct sockaddr_in *)addr;
3472 break;
3473 case AF_INET6:
3474 sin6 = (struct sockaddr_in6 *)addr;
3475 break;
3476 default:
3477 return -EINVAL;
3478 }
3479
3480 switch (param) {
3481 case ISCSI_PARAM_CONN_ADDRESS:
3482 case ISCSI_HOST_PARAM_IPADDRESS:
3483 if (sin)
3484 len = sprintf(buf, "%pI4\n", &sin->sin_addr.s_addr);
3485 else
3486 len = sprintf(buf, "%pI6\n", &sin6->sin6_addr);
3487 break;
3488 case ISCSI_PARAM_CONN_PORT:
3489 case ISCSI_PARAM_LOCAL_PORT:
3490 if (sin)
3491 len = sprintf(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3492 else
3493 len = sprintf(buf, "%hu\n",
3494 be16_to_cpu(sin6->sin6_port));
3495 break;
3496 default:
3497 return -EINVAL;
3498 }
3499
3500 return len;
3501 }
3502 EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3503
3504 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3505 enum iscsi_param param, char *buf)
3506 {
3507 struct iscsi_conn *conn = cls_conn->dd_data;
3508 int len;
3509
3510 switch(param) {
3511 case ISCSI_PARAM_PING_TMO:
3512 len = sprintf(buf, "%u\n", conn->ping_timeout);
3513 break;
3514 case ISCSI_PARAM_RECV_TMO:
3515 len = sprintf(buf, "%u\n", conn->recv_timeout);
3516 break;
3517 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3518 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
3519 break;
3520 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3521 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
3522 break;
3523 case ISCSI_PARAM_HDRDGST_EN:
3524 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
3525 break;
3526 case ISCSI_PARAM_DATADGST_EN:
3527 len = sprintf(buf, "%d\n", conn->datadgst_en);
3528 break;
3529 case ISCSI_PARAM_IFMARKER_EN:
3530 len = sprintf(buf, "%d\n", conn->ifmarker_en);
3531 break;
3532 case ISCSI_PARAM_OFMARKER_EN:
3533 len = sprintf(buf, "%d\n", conn->ofmarker_en);
3534 break;
3535 case ISCSI_PARAM_EXP_STATSN:
3536 len = sprintf(buf, "%u\n", conn->exp_statsn);
3537 break;
3538 case ISCSI_PARAM_PERSISTENT_PORT:
3539 len = sprintf(buf, "%d\n", conn->persistent_port);
3540 break;
3541 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3542 len = sprintf(buf, "%s\n", conn->persistent_address);
3543 break;
3544 case ISCSI_PARAM_STATSN:
3545 len = sprintf(buf, "%u\n", conn->statsn);
3546 break;
3547 case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3548 len = sprintf(buf, "%u\n", conn->max_segment_size);
3549 break;
3550 case ISCSI_PARAM_KEEPALIVE_TMO:
3551 len = sprintf(buf, "%u\n", conn->keepalive_tmo);
3552 break;
3553 case ISCSI_PARAM_LOCAL_PORT:
3554 len = sprintf(buf, "%u\n", conn->local_port);
3555 break;
3556 case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3557 len = sprintf(buf, "%u\n", conn->tcp_timestamp_stat);
3558 break;
3559 case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3560 len = sprintf(buf, "%u\n", conn->tcp_nagle_disable);
3561 break;
3562 case ISCSI_PARAM_TCP_WSF_DISABLE:
3563 len = sprintf(buf, "%u\n", conn->tcp_wsf_disable);
3564 break;
3565 case ISCSI_PARAM_TCP_TIMER_SCALE:
3566 len = sprintf(buf, "%u\n", conn->tcp_timer_scale);
3567 break;
3568 case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3569 len = sprintf(buf, "%u\n", conn->tcp_timestamp_en);
3570 break;
3571 case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3572 len = sprintf(buf, "%u\n", conn->fragment_disable);
3573 break;
3574 case ISCSI_PARAM_IPV4_TOS:
3575 len = sprintf(buf, "%u\n", conn->ipv4_tos);
3576 break;
3577 case ISCSI_PARAM_IPV6_TC:
3578 len = sprintf(buf, "%u\n", conn->ipv6_traffic_class);
3579 break;
3580 case ISCSI_PARAM_IPV6_FLOW_LABEL:
3581 len = sprintf(buf, "%u\n", conn->ipv6_flow_label);
3582 break;
3583 case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3584 len = sprintf(buf, "%u\n", conn->is_fw_assigned_ipv6);
3585 break;
3586 case ISCSI_PARAM_TCP_XMIT_WSF:
3587 len = sprintf(buf, "%u\n", conn->tcp_xmit_wsf);
3588 break;
3589 case ISCSI_PARAM_TCP_RECV_WSF:
3590 len = sprintf(buf, "%u\n", conn->tcp_recv_wsf);
3591 break;
3592 case ISCSI_PARAM_LOCAL_IPADDR:
3593 len = sprintf(buf, "%s\n", conn->local_ipaddr);
3594 break;
3595 default:
3596 return -ENOSYS;
3597 }
3598
3599 return len;
3600 }
3601 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3602
3603 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3604 char *buf)
3605 {
3606 struct iscsi_host *ihost = shost_priv(shost);
3607 int len;
3608
3609 switch (param) {
3610 case ISCSI_HOST_PARAM_NETDEV_NAME:
3611 len = sprintf(buf, "%s\n", ihost->netdev);
3612 break;
3613 case ISCSI_HOST_PARAM_HWADDRESS:
3614 len = sprintf(buf, "%s\n", ihost->hwaddress);
3615 break;
3616 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3617 len = sprintf(buf, "%s\n", ihost->initiatorname);
3618 break;
3619 default:
3620 return -ENOSYS;
3621 }
3622
3623 return len;
3624 }
3625 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3626
3627 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3628 char *buf, int buflen)
3629 {
3630 struct iscsi_host *ihost = shost_priv(shost);
3631
3632 switch (param) {
3633 case ISCSI_HOST_PARAM_NETDEV_NAME:
3634 return iscsi_switch_str_param(&ihost->netdev, buf);
3635 case ISCSI_HOST_PARAM_HWADDRESS:
3636 return iscsi_switch_str_param(&ihost->hwaddress, buf);
3637 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3638 return iscsi_switch_str_param(&ihost->initiatorname, buf);
3639 default:
3640 return -ENOSYS;
3641 }
3642
3643 return 0;
3644 }
3645 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3646
3647 MODULE_AUTHOR("Mike Christie");
3648 MODULE_DESCRIPTION("iSCSI library functions");
3649 MODULE_LICENSE("GPL");
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