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gpio: rcar: Fix runtime PM imbalance on error
[linux/fpc-iii.git] / drivers / scsi / libiscsi.c
blob874dd4beed10431f2ab31e45bfeec66f75b88999
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * iSCSI lib functions
4 *
5 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
6 * Copyright (C) 2004 - 2006 Mike Christie
7 * Copyright (C) 2004 - 2005 Dmitry Yusupov
8 * Copyright (C) 2004 - 2005 Alex Aizman
9 * maintained by open-iscsi@googlegroups.com
10 */
11 #include <linux/types.h>
12 #include <linux/kfifo.h>
13 #include <linux/delay.h>
14 #include <linux/log2.h>
15 #include <linux/slab.h>
16 #include <linux/sched/signal.h>
17 #include <linux/module.h>
18 #include <asm/unaligned.h>
19 #include <net/tcp.h>
20 #include <scsi/scsi_cmnd.h>
21 #include <scsi/scsi_device.h>
22 #include <scsi/scsi_eh.h>
23 #include <scsi/scsi_tcq.h>
24 #include <scsi/scsi_host.h>
25 #include <scsi/scsi.h>
26 #include <scsi/iscsi_proto.h>
27 #include <scsi/scsi_transport.h>
28 #include <scsi/scsi_transport_iscsi.h>
29 #include <scsi/libiscsi.h>
30 #include <trace/events/iscsi.h>
31
32 static int iscsi_dbg_lib_conn;
33 module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
34 S_IRUGO | S_IWUSR);
35 MODULE_PARM_DESC(debug_libiscsi_conn,
36 "Turn on debugging for connections in libiscsi module. "
37 "Set to 1 to turn on, and zero to turn off. Default is off.");
38
39 static int iscsi_dbg_lib_session;
40 module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
41 S_IRUGO | S_IWUSR);
42 MODULE_PARM_DESC(debug_libiscsi_session,
43 "Turn on debugging for sessions in libiscsi module. "
44 "Set to 1 to turn on, and zero to turn off. Default is off.");
45
46 static int iscsi_dbg_lib_eh;
47 module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
48 S_IRUGO | S_IWUSR);
49 MODULE_PARM_DESC(debug_libiscsi_eh,
50 "Turn on debugging for error handling in libiscsi module. "
51 "Set to 1 to turn on, and zero to turn off. Default is off.");
52
53 #define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...) \
54 do { \
55 if (iscsi_dbg_lib_conn) \
56 iscsi_conn_printk(KERN_INFO, _conn, \
57 "%s " dbg_fmt, \
58 __func__, ##arg); \
59 iscsi_dbg_trace(trace_iscsi_dbg_conn, \
60 &(_conn)->cls_conn->dev, \
61 "%s " dbg_fmt, __func__, ##arg);\
62 } while (0);
63
64 #define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...) \
65 do { \
66 if (iscsi_dbg_lib_session) \
67 iscsi_session_printk(KERN_INFO, _session, \
68 "%s " dbg_fmt, \
69 __func__, ##arg); \
70 iscsi_dbg_trace(trace_iscsi_dbg_session, \
71 &(_session)->cls_session->dev, \
72 "%s " dbg_fmt, __func__, ##arg); \
73 } while (0);
74
75 #define ISCSI_DBG_EH(_session, dbg_fmt, arg...) \
76 do { \
77 if (iscsi_dbg_lib_eh) \
78 iscsi_session_printk(KERN_INFO, _session, \
79 "%s " dbg_fmt, \
80 __func__, ##arg); \
81 iscsi_dbg_trace(trace_iscsi_dbg_eh, \
82 &(_session)->cls_session->dev, \
83 "%s " dbg_fmt, __func__, ##arg); \
84 } while (0);
85
86 inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
87 {
88 struct Scsi_Host *shost = conn->session->host;
89 struct iscsi_host *ihost = shost_priv(shost);
90
91 if (ihost->workq)
92 queue_work(ihost->workq, &conn->xmitwork);
93 }
94 EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
95
96 static void __iscsi_update_cmdsn(struct iscsi_session *session,
97 uint32_t exp_cmdsn, uint32_t max_cmdsn)
98 {
99 /*
100 * standard specifies this check for when to update expected and
101 * max sequence numbers
102 */
103 if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
104 return;
105
106 if (exp_cmdsn != session->exp_cmdsn &&
107 !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
108 session->exp_cmdsn = exp_cmdsn;
109
110 if (max_cmdsn != session->max_cmdsn &&
111 !iscsi_sna_lt(max_cmdsn, session->max_cmdsn))
112 session->max_cmdsn = max_cmdsn;
113 }
114
115 void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
116 {
117 __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
118 be32_to_cpu(hdr->max_cmdsn));
119 }
120 EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
121
122 /**
123 * iscsi_prep_data_out_pdu - initialize Data-Out
124 * @task: scsi command task
125 * @r2t: R2T info
126 * @hdr: iscsi data in pdu
127 *
128 * Notes:
129 * Initialize Data-Out within this R2T sequence and finds
130 * proper data_offset within this SCSI command.
131 *
132 * This function is called with connection lock taken.
133 **/
134 void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
135 struct iscsi_data *hdr)
136 {
137 struct iscsi_conn *conn = task->conn;
138 unsigned int left = r2t->data_length - r2t->sent;
139
140 task->hdr_len = sizeof(struct iscsi_data);
141
142 memset(hdr, 0, sizeof(struct iscsi_data));
143 hdr->ttt = r2t->ttt;
144 hdr->datasn = cpu_to_be32(r2t->datasn);
145 r2t->datasn++;
146 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
147 hdr->lun = task->lun;
148 hdr->itt = task->hdr_itt;
149 hdr->exp_statsn = r2t->exp_statsn;
150 hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
151 if (left > conn->max_xmit_dlength) {
152 hton24(hdr->dlength, conn->max_xmit_dlength);
153 r2t->data_count = conn->max_xmit_dlength;
154 hdr->flags = 0;
155 } else {
156 hton24(hdr->dlength, left);
157 r2t->data_count = left;
158 hdr->flags = ISCSI_FLAG_CMD_FINAL;
159 }
160 conn->dataout_pdus_cnt++;
161 }
162 EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
163
164 static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
165 {
166 unsigned exp_len = task->hdr_len + len;
167
168 if (exp_len > task->hdr_max) {
169 WARN_ON(1);
170 return -EINVAL;
171 }
172
173 WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
174 task->hdr_len = exp_len;
175 return 0;
176 }
177
178 /*
179 * make an extended cdb AHS
180 */
181 static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
182 {
183 struct scsi_cmnd *cmd = task->sc;
184 unsigned rlen, pad_len;
185 unsigned short ahslength;
186 struct iscsi_ecdb_ahdr *ecdb_ahdr;
187 int rc;
188
189 ecdb_ahdr = iscsi_next_hdr(task);
190 rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
191
192 BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
193 ahslength = rlen + sizeof(ecdb_ahdr->reserved);
194
195 pad_len = iscsi_padding(rlen);
196
197 rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
198 sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
199 if (rc)
200 return rc;
201
202 if (pad_len)
203 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
204
205 ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
206 ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
207 ecdb_ahdr->reserved = 0;
208 memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
209
210 ISCSI_DBG_SESSION(task->conn->session,
211 "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
212 "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
213 "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
214 task->hdr_len);
215 return 0;
216 }
217
218 /**
219 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
220 * @task: iscsi task
221 * @opcode: opcode to check for
222 *
223 * During TMF a task has to be checked if it's affected.
224 * All unrelated I/O can be passed through, but I/O to the
225 * affected LUN should be restricted.
226 * If 'fast_abort' is set we won't be sending any I/O to the
227 * affected LUN.
228 * Otherwise the target is waiting for all TTTs to be completed,
229 * so we have to send all outstanding Data-Out PDUs to the target.
230 */
231 static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
232 {
233 struct iscsi_conn *conn = task->conn;
234 struct iscsi_tm *tmf = &conn->tmhdr;
235 u64 hdr_lun;
236
237 if (conn->tmf_state == TMF_INITIAL)
238 return 0;
239
240 if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
241 return 0;
242
243 switch (ISCSI_TM_FUNC_VALUE(tmf)) {
244 case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
245 /*
246 * Allow PDUs for unrelated LUNs
247 */
248 hdr_lun = scsilun_to_int(&tmf->lun);
249 if (hdr_lun != task->sc->device->lun)
250 return 0;
251 /* fall through */
252 case ISCSI_TM_FUNC_TARGET_WARM_RESET:
253 /*
254 * Fail all SCSI cmd PDUs
255 */
256 if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
257 iscsi_conn_printk(KERN_INFO, conn,
258 "task [op %x itt "
259 "0x%x/0x%x] "
260 "rejected.\n",
261 opcode, task->itt,
262 task->hdr_itt);
263 return -EACCES;
264 }
265 /*
266 * And also all data-out PDUs in response to R2T
267 * if fast_abort is set.
268 */
269 if (conn->session->fast_abort) {
270 iscsi_conn_printk(KERN_INFO, conn,
271 "task [op %x itt "
272 "0x%x/0x%x] fast abort.\n",
273 opcode, task->itt,
274 task->hdr_itt);
275 return -EACCES;
276 }
277 break;
278 case ISCSI_TM_FUNC_ABORT_TASK:
279 /*
280 * the caller has already checked if the task
281 * they want to abort was in the pending queue so if
282 * we are here the cmd pdu has gone out already, and
283 * we will only hit this for data-outs
284 */
285 if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
286 task->hdr_itt == tmf->rtt) {
287 ISCSI_DBG_SESSION(conn->session,
288 "Preventing task %x/%x from sending "
289 "data-out due to abort task in "
290 "progress\n", task->itt,
291 task->hdr_itt);
292 return -EACCES;
293 }
294 break;
295 }
296
297 return 0;
298 }
299
300 /**
301 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
302 * @task: iscsi task
303 *
304 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
305 * fields like dlength or final based on how much data it sends
306 */
307 static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
308 {
309 struct iscsi_conn *conn = task->conn;
310 struct iscsi_session *session = conn->session;
311 struct scsi_cmnd *sc = task->sc;
312 struct iscsi_scsi_req *hdr;
313 unsigned hdrlength, cmd_len, transfer_length;
314 itt_t itt;
315 int rc;
316
317 rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
318 if (rc)
319 return rc;
320
321 if (conn->session->tt->alloc_pdu) {
322 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
323 if (rc)
324 return rc;
325 }
326 hdr = (struct iscsi_scsi_req *)task->hdr;
327 itt = hdr->itt;
328 memset(hdr, 0, sizeof(*hdr));
329
330 if (session->tt->parse_pdu_itt)
331 hdr->itt = task->hdr_itt = itt;
332 else
333 hdr->itt = task->hdr_itt = build_itt(task->itt,
334 task->conn->session->age);
335 task->hdr_len = 0;
336 rc = iscsi_add_hdr(task, sizeof(*hdr));
337 if (rc)
338 return rc;
339 hdr->opcode = ISCSI_OP_SCSI_CMD;
340 hdr->flags = ISCSI_ATTR_SIMPLE;
341 int_to_scsilun(sc->device->lun, &hdr->lun);
342 task->lun = hdr->lun;
343 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
344 cmd_len = sc->cmd_len;
345 if (cmd_len < ISCSI_CDB_SIZE)
346 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
347 else if (cmd_len > ISCSI_CDB_SIZE) {
348 rc = iscsi_prep_ecdb_ahs(task);
349 if (rc)
350 return rc;
351 cmd_len = ISCSI_CDB_SIZE;
352 }
353 memcpy(hdr->cdb, sc->cmnd, cmd_len);
354
355 task->imm_count = 0;
356 if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL)
357 task->protected = true;
358
359 transfer_length = scsi_transfer_length(sc);
360 hdr->data_length = cpu_to_be32(transfer_length);
361 if (sc->sc_data_direction == DMA_TO_DEVICE) {
362 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
363
364 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
365 /*
366 * Write counters:
367 *
368 * imm_count bytes to be sent right after
369 * SCSI PDU Header
370 *
371 * unsol_count bytes(as Data-Out) to be sent
372 * without R2T ack right after
373 * immediate data
374 *
375 * r2t data_length bytes to be sent via R2T ack's
376 *
377 * pad_count bytes to be sent as zero-padding
378 */
379 memset(r2t, 0, sizeof(*r2t));
380
381 if (session->imm_data_en) {
382 if (transfer_length >= session->first_burst)
383 task->imm_count = min(session->first_burst,
384 conn->max_xmit_dlength);
385 else
386 task->imm_count = min(transfer_length,
387 conn->max_xmit_dlength);
388 hton24(hdr->dlength, task->imm_count);
389 } else
390 zero_data(hdr->dlength);
391
392 if (!session->initial_r2t_en) {
393 r2t->data_length = min(session->first_burst,
394 transfer_length) -
395 task->imm_count;
396 r2t->data_offset = task->imm_count;
397 r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
398 r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
399 }
400
401 if (!task->unsol_r2t.data_length)
402 /* No unsolicit Data-Out's */
403 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
404 } else {
405 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
406 zero_data(hdr->dlength);
407
408 if (sc->sc_data_direction == DMA_FROM_DEVICE)
409 hdr->flags |= ISCSI_FLAG_CMD_READ;
410 }
411
412 /* calculate size of additional header segments (AHSs) */
413 hdrlength = task->hdr_len - sizeof(*hdr);
414
415 WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
416 hdrlength /= ISCSI_PAD_LEN;
417
418 WARN_ON(hdrlength >= 256);
419 hdr->hlength = hdrlength & 0xFF;
420 hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
421
422 if (session->tt->init_task && session->tt->init_task(task))
423 return -EIO;
424
425 task->state = ISCSI_TASK_RUNNING;
426 session->cmdsn++;
427
428 conn->scsicmd_pdus_cnt++;
429 ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
430 "itt 0x%x len %d cmdsn %d win %d]\n",
431 sc->sc_data_direction == DMA_TO_DEVICE ?
432 "write" : "read", conn->id, sc, sc->cmnd[0],
433 task->itt, transfer_length,
434 session->cmdsn,
435 session->max_cmdsn - session->exp_cmdsn + 1);
436 return 0;
437 }
438
439 /**
440 * iscsi_free_task - free a task
441 * @task: iscsi cmd task
442 *
443 * Must be called with session back_lock.
444 * This function returns the scsi command to scsi-ml or cleans
445 * up mgmt tasks then returns the task to the pool.
446 */
447 static void iscsi_free_task(struct iscsi_task *task)
448 {
449 struct iscsi_conn *conn = task->conn;
450 struct iscsi_session *session = conn->session;
451 struct scsi_cmnd *sc = task->sc;
452 int oldstate = task->state;
453
454 ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
455 task->itt, task->state, task->sc);
456
457 session->tt->cleanup_task(task);
458 task->state = ISCSI_TASK_FREE;
459 task->sc = NULL;
460 /*
461 * login task is preallocated so do not free
462 */
463 if (conn->login_task == task)
464 return;
465
466 kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
467
468 if (sc) {
469 /* SCSI eh reuses commands to verify us */
470 sc->SCp.ptr = NULL;
471 /*
472 * queue command may call this to free the task, so
473 * it will decide how to return sc to scsi-ml.
474 */
475 if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
476 sc->scsi_done(sc);
477 }
478 }
479
480 void __iscsi_get_task(struct iscsi_task *task)
481 {
482 refcount_inc(&task->refcount);
483 }
484 EXPORT_SYMBOL_GPL(__iscsi_get_task);
485
486 void __iscsi_put_task(struct iscsi_task *task)
487 {
488 if (refcount_dec_and_test(&task->refcount))
489 iscsi_free_task(task);
490 }
491 EXPORT_SYMBOL_GPL(__iscsi_put_task);
492
493 void iscsi_put_task(struct iscsi_task *task)
494 {
495 struct iscsi_session *session = task->conn->session;
496
497 /* regular RX path uses back_lock */
498 spin_lock_bh(&session->back_lock);
499 __iscsi_put_task(task);
500 spin_unlock_bh(&session->back_lock);
501 }
502 EXPORT_SYMBOL_GPL(iscsi_put_task);
503
504 /**
505 * iscsi_complete_task - finish a task
506 * @task: iscsi cmd task
507 * @state: state to complete task with
508 *
509 * Must be called with session back_lock.
510 */
511 static void iscsi_complete_task(struct iscsi_task *task, int state)
512 {
513 struct iscsi_conn *conn = task->conn;
514
515 ISCSI_DBG_SESSION(conn->session,
516 "complete task itt 0x%x state %d sc %p\n",
517 task->itt, task->state, task->sc);
518 if (task->state == ISCSI_TASK_COMPLETED ||
519 task->state == ISCSI_TASK_ABRT_TMF ||
520 task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
521 task->state == ISCSI_TASK_REQUEUE_SCSIQ)
522 return;
523 WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
524 task->state = state;
525
526 spin_lock_bh(&conn->taskqueuelock);
527 if (!list_empty(&task->running)) {
528 pr_debug_once("%s while task on list", __func__);
529 list_del_init(&task->running);
530 }
531 spin_unlock_bh(&conn->taskqueuelock);
532
533 if (conn->task == task)
534 conn->task = NULL;
535
536 if (conn->ping_task == task)
537 conn->ping_task = NULL;
538
539 /* release get from queueing */
540 __iscsi_put_task(task);
541 }
542
543 /**
544 * iscsi_complete_scsi_task - finish scsi task normally
545 * @task: iscsi task for scsi cmd
546 * @exp_cmdsn: expected cmd sn in cpu format
547 * @max_cmdsn: max cmd sn in cpu format
548 *
549 * This is used when drivers do not need or cannot perform
550 * lower level pdu processing.
551 *
552 * Called with session back_lock
553 */
554 void iscsi_complete_scsi_task(struct iscsi_task *task,
555 uint32_t exp_cmdsn, uint32_t max_cmdsn)
556 {
557 struct iscsi_conn *conn = task->conn;
558
559 ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
560
561 conn->last_recv = jiffies;
562 __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
563 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
564 }
565 EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
566
567
568 /*
569 * session back_lock must be held and if not called for a task that is
570 * still pending or from the xmit thread, then xmit thread must
571 * be suspended.
572 */
573 static void fail_scsi_task(struct iscsi_task *task, int err)
574 {
575 struct iscsi_conn *conn = task->conn;
576 struct scsi_cmnd *sc;
577 int state;
578
579 /*
580 * if a command completes and we get a successful tmf response
581 * we will hit this because the scsi eh abort code does not take
582 * a ref to the task.
583 */
584 sc = task->sc;
585 if (!sc)
586 return;
587
588 if (task->state == ISCSI_TASK_PENDING) {
589 /*
590 * cmd never made it to the xmit thread, so we should not count
591 * the cmd in the sequencing
592 */
593 conn->session->queued_cmdsn--;
594 /* it was never sent so just complete like normal */
595 state = ISCSI_TASK_COMPLETED;
596 } else if (err == DID_TRANSPORT_DISRUPTED)
597 state = ISCSI_TASK_ABRT_SESS_RECOV;
598 else
599 state = ISCSI_TASK_ABRT_TMF;
600
601 sc->result = err << 16;
602 scsi_set_resid(sc, scsi_bufflen(sc));
603
604 /* regular RX path uses back_lock */
605 spin_lock_bh(&conn->session->back_lock);
606 iscsi_complete_task(task, state);
607 spin_unlock_bh(&conn->session->back_lock);
608 }
609
610 static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
611 struct iscsi_task *task)
612 {
613 struct iscsi_session *session = conn->session;
614 struct iscsi_hdr *hdr = task->hdr;
615 struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
616 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
617
618 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
619 return -ENOTCONN;
620
621 if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
622 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
623 /*
624 * pre-format CmdSN for outgoing PDU.
625 */
626 nop->cmdsn = cpu_to_be32(session->cmdsn);
627 if (hdr->itt != RESERVED_ITT) {
628 /*
629 * TODO: We always use immediate for normal session pdus.
630 * If we start to send tmfs or nops as non-immediate then
631 * we should start checking the cmdsn numbers for mgmt tasks.
632 *
633 * During discovery sessions iscsid sends TEXT as non immediate,
634 * but we always only send one PDU at a time.
635 */
636 if (conn->c_stage == ISCSI_CONN_STARTED &&
637 !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
638 session->queued_cmdsn++;
639 session->cmdsn++;
640 }
641 }
642
643 if (session->tt->init_task && session->tt->init_task(task))
644 return -EIO;
645
646 if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
647 session->state = ISCSI_STATE_LOGGING_OUT;
648
649 task->state = ISCSI_TASK_RUNNING;
650 ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
651 "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
652 hdr->itt, task->data_count);
653 return 0;
654 }
655
656 static struct iscsi_task *
657 __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
658 char *data, uint32_t data_size)
659 {
660 struct iscsi_session *session = conn->session;
661 struct iscsi_host *ihost = shost_priv(session->host);
662 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
663 struct iscsi_task *task;
664 itt_t itt;
665
666 if (session->state == ISCSI_STATE_TERMINATE)
667 return NULL;
668
669 if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
670 /*
671 * Login and Text are sent serially, in
672 * request-followed-by-response sequence.
673 * Same task can be used. Same ITT must be used.
674 * Note that login_task is preallocated at conn_create().
675 */
676 if (conn->login_task->state != ISCSI_TASK_FREE) {
677 iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
678 "progress. Cannot start new task.\n");
679 return NULL;
680 }
681
682 if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
683 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);
684 return NULL;
685 }
686
687 task = conn->login_task;
688 } else {
689 if (session->state != ISCSI_STATE_LOGGED_IN)
690 return NULL;
691
692 if (data_size != 0) {
693 iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
694 return NULL;
695 }
696
697 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
698 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
699
700 if (!kfifo_out(&session->cmdpool.queue,
701 (void*)&task, sizeof(void*)))
702 return NULL;
703 }
704 /*
705 * released in complete pdu for task we expect a response for, and
706 * released by the lld when it has transmitted the task for
707 * pdus we do not expect a response for.
708 */
709 refcount_set(&task->refcount, 1);
710 task->conn = conn;
711 task->sc = NULL;
712 INIT_LIST_HEAD(&task->running);
713 task->state = ISCSI_TASK_PENDING;
714
715 if (data_size) {
716 memcpy(task->data, data, data_size);
717 task->data_count = data_size;
718 } else
719 task->data_count = 0;
720
721 if (conn->session->tt->alloc_pdu) {
722 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
723 iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
724 "pdu for mgmt task.\n");
725 goto free_task;
726 }
727 }
728
729 itt = task->hdr->itt;
730 task->hdr_len = sizeof(struct iscsi_hdr);
731 memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
732
733 if (hdr->itt != RESERVED_ITT) {
734 if (session->tt->parse_pdu_itt)
735 task->hdr->itt = itt;
736 else
737 task->hdr->itt = build_itt(task->itt,
738 task->conn->session->age);
739 }
740
741 if (!ihost->workq) {
742 if (iscsi_prep_mgmt_task(conn, task))
743 goto free_task;
744
745 if (session->tt->xmit_task(task))
746 goto free_task;
747 } else {
748 spin_lock_bh(&conn->taskqueuelock);
749 list_add_tail(&task->running, &conn->mgmtqueue);
750 spin_unlock_bh(&conn->taskqueuelock);
751 iscsi_conn_queue_work(conn);
752 }
753
754 return task;
755
756 free_task:
757 /* regular RX path uses back_lock */
758 spin_lock(&session->back_lock);
759 __iscsi_put_task(task);
760 spin_unlock(&session->back_lock);
761 return NULL;
762 }
763
764 int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
765 char *data, uint32_t data_size)
766 {
767 struct iscsi_conn *conn = cls_conn->dd_data;
768 struct iscsi_session *session = conn->session;
769 int err = 0;
770
771 spin_lock_bh(&session->frwd_lock);
772 if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
773 err = -EPERM;
774 spin_unlock_bh(&session->frwd_lock);
775 return err;
776 }
777 EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
778
779 /**
780 * iscsi_cmd_rsp - SCSI Command Response processing
781 * @conn: iscsi connection
782 * @hdr: iscsi header
783 * @task: scsi command task
784 * @data: cmd data buffer
785 * @datalen: len of buffer
786 *
787 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
788 * then completes the command and task. called under back_lock
789 **/
790 static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
791 struct iscsi_task *task, char *data,
792 int datalen)
793 {
794 struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
795 struct iscsi_session *session = conn->session;
796 struct scsi_cmnd *sc = task->sc;
797
798 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
799 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
800
801 sc->result = (DID_OK << 16) | rhdr->cmd_status;
802
803 if (task->protected) {
804 sector_t sector;
805 u8 ascq;
806
807 /**
808 * Transports that didn't implement check_protection
809 * callback but still published T10-PI support to scsi-mid
810 * deserve this BUG_ON.
811 **/
812 BUG_ON(!session->tt->check_protection);
813
814 ascq = session->tt->check_protection(task, &sector);
815 if (ascq) {
816 sc->result = DRIVER_SENSE << 24 |
817 SAM_STAT_CHECK_CONDITION;
818 scsi_build_sense_buffer(1, sc->sense_buffer,
819 ILLEGAL_REQUEST, 0x10, ascq);
820 scsi_set_sense_information(sc->sense_buffer,
821 SCSI_SENSE_BUFFERSIZE,
822 sector);
823 goto out;
824 }
825 }
826
827 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
828 sc->result = DID_ERROR << 16;
829 goto out;
830 }
831
832 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
833 uint16_t senselen;
834
835 if (datalen < 2) {
836 invalid_datalen:
837 iscsi_conn_printk(KERN_ERR, conn,
838 "Got CHECK_CONDITION but invalid data "
839 "buffer size of %d\n", datalen);
840 sc->result = DID_BAD_TARGET << 16;
841 goto out;
842 }
843
844 senselen = get_unaligned_be16(data);
845 if (datalen < senselen)
846 goto invalid_datalen;
847
848 memcpy(sc->sense_buffer, data + 2,
849 min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
850 ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
851 min_t(uint16_t, senselen,
852 SCSI_SENSE_BUFFERSIZE));
853 }
854
855 if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
856 ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
857 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
858 }
859
860 if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
861 ISCSI_FLAG_CMD_OVERFLOW)) {
862 int res_count = be32_to_cpu(rhdr->residual_count);
863
864 if (res_count > 0 &&
865 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
866 res_count <= scsi_bufflen(sc)))
867 /* write side for bidi or uni-io set_resid */
868 scsi_set_resid(sc, res_count);
869 else
870 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
871 }
872 out:
873 ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
874 sc, sc->result, task->itt);
875 conn->scsirsp_pdus_cnt++;
876 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
877 }
878
879 /**
880 * iscsi_data_in_rsp - SCSI Data-In Response processing
881 * @conn: iscsi connection
882 * @hdr: iscsi pdu
883 * @task: scsi command task
884 *
885 * iscsi_data_in_rsp sets up the scsi_cmnd fields based on the data received
886 * then completes the command and task. called under back_lock
887 **/
888 static void
889 iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
890 struct iscsi_task *task)
891 {
892 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
893 struct scsi_cmnd *sc = task->sc;
894
895 if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
896 return;
897
898 iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
899 sc->result = (DID_OK << 16) | rhdr->cmd_status;
900 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
901 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
902 ISCSI_FLAG_DATA_OVERFLOW)) {
903 int res_count = be32_to_cpu(rhdr->residual_count);
904
905 if (res_count > 0 &&
906 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
907 res_count <= sc->sdb.length))
908 scsi_set_resid(sc, res_count);
909 else
910 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
911 }
912
913 ISCSI_DBG_SESSION(conn->session, "data in with status done "
914 "[sc %p res %d itt 0x%x]\n",
915 sc, sc->result, task->itt);
916 conn->scsirsp_pdus_cnt++;
917 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
918 }
919
920 static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
921 {
922 struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
923
924 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
925 conn->tmfrsp_pdus_cnt++;
926
927 if (conn->tmf_state != TMF_QUEUED)
928 return;
929
930 if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
931 conn->tmf_state = TMF_SUCCESS;
932 else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
933 conn->tmf_state = TMF_NOT_FOUND;
934 else
935 conn->tmf_state = TMF_FAILED;
936 wake_up(&conn->ehwait);
937 }
938
939 static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
940 {
941 struct iscsi_nopout hdr;
942 struct iscsi_task *task;
943
944 if (!rhdr && conn->ping_task)
945 return -EINVAL;
946
947 memset(&hdr, 0, sizeof(struct iscsi_nopout));
948 hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
949 hdr.flags = ISCSI_FLAG_CMD_FINAL;
950
951 if (rhdr) {
952 hdr.lun = rhdr->lun;
953 hdr.ttt = rhdr->ttt;
954 hdr.itt = RESERVED_ITT;
955 } else
956 hdr.ttt = RESERVED_ITT;
957
958 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
959 if (!task) {
960 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
961 return -EIO;
962 } else if (!rhdr) {
963 /* only track our nops */
964 conn->ping_task = task;
965 conn->last_ping = jiffies;
966 }
967
968 return 0;
969 }
970
971 /**
972 * iscsi_nop_out_rsp - SCSI NOP Response processing
973 * @task: scsi command task
974 * @nop: the nop structure
975 * @data: where to put the data
976 * @datalen: length of data
977 *
978 * iscsi_nop_out_rsp handles nop response from use or
979 * from user space. called under back_lock
980 **/
981 static int iscsi_nop_out_rsp(struct iscsi_task *task,
982 struct iscsi_nopin *nop, char *data, int datalen)
983 {
984 struct iscsi_conn *conn = task->conn;
985 int rc = 0;
986
987 if (conn->ping_task != task) {
988 /*
989 * If this is not in response to one of our
990 * nops then it must be from userspace.
991 */
992 if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
993 data, datalen))
994 rc = ISCSI_ERR_CONN_FAILED;
995 } else
996 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
997 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
998 return rc;
999 }
1000
1001 static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1002 char *data, int datalen)
1003 {
1004 struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1005 struct iscsi_hdr rejected_pdu;
1006 int opcode, rc = 0;
1007
1008 conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1009
1010 if (ntoh24(reject->dlength) > datalen ||
1011 ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1012 iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1013 "pdu. Invalid data length (pdu dlength "
1014 "%u, datalen %d\n", ntoh24(reject->dlength),
1015 datalen);
1016 return ISCSI_ERR_PROTO;
1017 }
1018 memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1019 opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1020
1021 switch (reject->reason) {
1022 case ISCSI_REASON_DATA_DIGEST_ERROR:
1023 iscsi_conn_printk(KERN_ERR, conn,
1024 "pdu (op 0x%x itt 0x%x) rejected "
1025 "due to DataDigest error.\n",
1026 opcode, rejected_pdu.itt);
1027 break;
1028 case ISCSI_REASON_IMM_CMD_REJECT:
1029 iscsi_conn_printk(KERN_ERR, conn,
1030 "pdu (op 0x%x itt 0x%x) rejected. Too many "
1031 "immediate commands.\n",
1032 opcode, rejected_pdu.itt);
1033 /*
1034 * We only send one TMF at a time so if the target could not
1035 * handle it, then it should get fixed (RFC mandates that
1036 * a target can handle one immediate TMF per conn).
1037 *
1038 * For nops-outs, we could have sent more than one if
1039 * the target is sending us lots of nop-ins
1040 */
1041 if (opcode != ISCSI_OP_NOOP_OUT)
1042 return 0;
1043
1044 if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1045 /*
1046 * nop-out in response to target's nop-out rejected.
1047 * Just resend.
1048 */
1049 /* In RX path we are under back lock */
1050 spin_unlock(&conn->session->back_lock);
1051 spin_lock(&conn->session->frwd_lock);
1052 iscsi_send_nopout(conn,
1053 (struct iscsi_nopin*)&rejected_pdu);
1054 spin_unlock(&conn->session->frwd_lock);
1055 spin_lock(&conn->session->back_lock);
1056 } else {
1057 struct iscsi_task *task;
1058 /*
1059 * Our nop as ping got dropped. We know the target
1060 * and transport are ok so just clean up
1061 */
1062 task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1063 if (!task) {
1064 iscsi_conn_printk(KERN_ERR, conn,
1065 "Invalid pdu reject. Could "
1066 "not lookup rejected task.\n");
1067 rc = ISCSI_ERR_BAD_ITT;
1068 } else
1069 rc = iscsi_nop_out_rsp(task,
1070 (struct iscsi_nopin*)&rejected_pdu,
1071 NULL, 0);
1072 }
1073 break;
1074 default:
1075 iscsi_conn_printk(KERN_ERR, conn,
1076 "pdu (op 0x%x itt 0x%x) rejected. Reason "
1077 "code 0x%x\n", rejected_pdu.opcode,
1078 rejected_pdu.itt, reject->reason);
1079 break;
1080 }
1081 return rc;
1082 }
1083
1084 /**
1085 * iscsi_itt_to_task - look up task by itt
1086 * @conn: iscsi connection
1087 * @itt: itt
1088 *
1089 * This should be used for mgmt tasks like login and nops, or if
1090 * the LDD's itt space does not include the session age.
1091 *
1092 * The session back_lock must be held.
1093 */
1094 struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1095 {
1096 struct iscsi_session *session = conn->session;
1097 int i;
1098
1099 if (itt == RESERVED_ITT)
1100 return NULL;
1101
1102 if (session->tt->parse_pdu_itt)
1103 session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1104 else
1105 i = get_itt(itt);
1106 if (i >= session->cmds_max)
1107 return NULL;
1108
1109 return session->cmds[i];
1110 }
1111 EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1112
1113 /**
1114 * __iscsi_complete_pdu - complete pdu
1115 * @conn: iscsi conn
1116 * @hdr: iscsi header
1117 * @data: data buffer
1118 * @datalen: len of data buffer
1119 *
1120 * Completes pdu processing by freeing any resources allocated at
1121 * queuecommand or send generic. session back_lock must be held and verify
1122 * itt must have been called.
1123 */
1124 int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1125 char *data, int datalen)
1126 {
1127 struct iscsi_session *session = conn->session;
1128 int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1129 struct iscsi_task *task;
1130 uint32_t itt;
1131
1132 conn->last_recv = jiffies;
1133 rc = iscsi_verify_itt(conn, hdr->itt);
1134 if (rc)
1135 return rc;
1136
1137 if (hdr->itt != RESERVED_ITT)
1138 itt = get_itt(hdr->itt);
1139 else
1140 itt = ~0U;
1141
1142 ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1143 opcode, conn->id, itt, datalen);
1144
1145 if (itt == ~0U) {
1146 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1147
1148 switch(opcode) {
1149 case ISCSI_OP_NOOP_IN:
1150 if (datalen) {
1151 rc = ISCSI_ERR_PROTO;
1152 break;
1153 }
1154
1155 if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1156 break;
1157
1158 /* In RX path we are under back lock */
1159 spin_unlock(&session->back_lock);
1160 spin_lock(&session->frwd_lock);
1161 iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1162 spin_unlock(&session->frwd_lock);
1163 spin_lock(&session->back_lock);
1164 break;
1165 case ISCSI_OP_REJECT:
1166 rc = iscsi_handle_reject(conn, hdr, data, datalen);
1167 break;
1168 case ISCSI_OP_ASYNC_EVENT:
1169 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1170 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1171 rc = ISCSI_ERR_CONN_FAILED;
1172 break;
1173 default:
1174 rc = ISCSI_ERR_BAD_OPCODE;
1175 break;
1176 }
1177 goto out;
1178 }
1179
1180 switch(opcode) {
1181 case ISCSI_OP_SCSI_CMD_RSP:
1182 case ISCSI_OP_SCSI_DATA_IN:
1183 task = iscsi_itt_to_ctask(conn, hdr->itt);
1184 if (!task)
1185 return ISCSI_ERR_BAD_ITT;
1186 task->last_xfer = jiffies;
1187 break;
1188 case ISCSI_OP_R2T:
1189 /*
1190 * LLD handles R2Ts if they need to.
1191 */
1192 return 0;
1193 case ISCSI_OP_LOGOUT_RSP:
1194 case ISCSI_OP_LOGIN_RSP:
1195 case ISCSI_OP_TEXT_RSP:
1196 case ISCSI_OP_SCSI_TMFUNC_RSP:
1197 case ISCSI_OP_NOOP_IN:
1198 task = iscsi_itt_to_task(conn, hdr->itt);
1199 if (!task)
1200 return ISCSI_ERR_BAD_ITT;
1201 break;
1202 default:
1203 return ISCSI_ERR_BAD_OPCODE;
1204 }
1205
1206 switch(opcode) {
1207 case ISCSI_OP_SCSI_CMD_RSP:
1208 iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1209 break;
1210 case ISCSI_OP_SCSI_DATA_IN:
1211 iscsi_data_in_rsp(conn, hdr, task);
1212 break;
1213 case ISCSI_OP_LOGOUT_RSP:
1214 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1215 if (datalen) {
1216 rc = ISCSI_ERR_PROTO;
1217 break;
1218 }
1219 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1220 goto recv_pdu;
1221 case ISCSI_OP_LOGIN_RSP:
1222 case ISCSI_OP_TEXT_RSP:
1223 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1224 /*
1225 * login related PDU's exp_statsn is handled in
1226 * userspace
1227 */
1228 goto recv_pdu;
1229 case ISCSI_OP_SCSI_TMFUNC_RSP:
1230 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1231 if (datalen) {
1232 rc = ISCSI_ERR_PROTO;
1233 break;
1234 }
1235
1236 iscsi_tmf_rsp(conn, hdr);
1237 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1238 break;
1239 case ISCSI_OP_NOOP_IN:
1240 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1241 if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1242 rc = ISCSI_ERR_PROTO;
1243 break;
1244 }
1245 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1246
1247 rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1248 data, datalen);
1249 break;
1250 default:
1251 rc = ISCSI_ERR_BAD_OPCODE;
1252 break;
1253 }
1254
1255 out:
1256 return rc;
1257 recv_pdu:
1258 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1259 rc = ISCSI_ERR_CONN_FAILED;
1260 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1261 return rc;
1262 }
1263 EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1264
1265 int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1266 char *data, int datalen)
1267 {
1268 int rc;
1269
1270 spin_lock(&conn->session->back_lock);
1271 rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1272 spin_unlock(&conn->session->back_lock);
1273 return rc;
1274 }
1275 EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1276
1277 int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1278 {
1279 struct iscsi_session *session = conn->session;
1280 int age = 0, i = 0;
1281
1282 if (itt == RESERVED_ITT)
1283 return 0;
1284
1285 if (session->tt->parse_pdu_itt)
1286 session->tt->parse_pdu_itt(conn, itt, &i, &age);
1287 else {
1288 i = get_itt(itt);
1289 age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1290 }
1291
1292 if (age != session->age) {
1293 iscsi_conn_printk(KERN_ERR, conn,
1294 "received itt %x expected session age (%x)\n",
1295 (__force u32)itt, session->age);
1296 return ISCSI_ERR_BAD_ITT;
1297 }
1298
1299 if (i >= session->cmds_max) {
1300 iscsi_conn_printk(KERN_ERR, conn,
1301 "received invalid itt index %u (max cmds "
1302 "%u.\n", i, session->cmds_max);
1303 return ISCSI_ERR_BAD_ITT;
1304 }
1305 return 0;
1306 }
1307 EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1308
1309 /**
1310 * iscsi_itt_to_ctask - look up ctask by itt
1311 * @conn: iscsi connection
1312 * @itt: itt
1313 *
1314 * This should be used for cmd tasks.
1315 *
1316 * The session back_lock must be held.
1317 */
1318 struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1319 {
1320 struct iscsi_task *task;
1321
1322 if (iscsi_verify_itt(conn, itt))
1323 return NULL;
1324
1325 task = iscsi_itt_to_task(conn, itt);
1326 if (!task || !task->sc)
1327 return NULL;
1328
1329 if (task->sc->SCp.phase != conn->session->age) {
1330 iscsi_session_printk(KERN_ERR, conn->session,
1331 "task's session age %d, expected %d\n",
1332 task->sc->SCp.phase, conn->session->age);
1333 return NULL;
1334 }
1335
1336 return task;
1337 }
1338 EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1339
1340 void iscsi_session_failure(struct iscsi_session *session,
1341 enum iscsi_err err)
1342 {
1343 struct iscsi_conn *conn;
1344 struct device *dev;
1345
1346 spin_lock_bh(&session->frwd_lock);
1347 conn = session->leadconn;
1348 if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1349 spin_unlock_bh(&session->frwd_lock);
1350 return;
1351 }
1352
1353 dev = get_device(&conn->cls_conn->dev);
1354 spin_unlock_bh(&session->frwd_lock);
1355 if (!dev)
1356 return;
1357 /*
1358 * if the host is being removed bypass the connection
1359 * recovery initialization because we are going to kill
1360 * the session.
1361 */
1362 if (err == ISCSI_ERR_INVALID_HOST)
1363 iscsi_conn_error_event(conn->cls_conn, err);
1364 else
1365 iscsi_conn_failure(conn, err);
1366 put_device(dev);
1367 }
1368 EXPORT_SYMBOL_GPL(iscsi_session_failure);
1369
1370 void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1371 {
1372 struct iscsi_session *session = conn->session;
1373
1374 spin_lock_bh(&session->frwd_lock);
1375 if (session->state == ISCSI_STATE_FAILED) {
1376 spin_unlock_bh(&session->frwd_lock);
1377 return;
1378 }
1379
1380 if (conn->stop_stage == 0)
1381 session->state = ISCSI_STATE_FAILED;
1382 spin_unlock_bh(&session->frwd_lock);
1383
1384 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1385 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1386 iscsi_conn_error_event(conn->cls_conn, err);
1387 }
1388 EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1389
1390 static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1391 {
1392 struct iscsi_session *session = conn->session;
1393
1394 /*
1395 * Check for iSCSI window and take care of CmdSN wrap-around
1396 */
1397 if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1398 ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1399 "%u MaxCmdSN %u CmdSN %u/%u\n",
1400 session->exp_cmdsn, session->max_cmdsn,
1401 session->cmdsn, session->queued_cmdsn);
1402 return -ENOSPC;
1403 }
1404 return 0;
1405 }
1406
1407 static int iscsi_xmit_task(struct iscsi_conn *conn)
1408 {
1409 struct iscsi_task *task = conn->task;
1410 int rc;
1411
1412 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
1413 return -ENODATA;
1414
1415 spin_lock_bh(&conn->session->back_lock);
1416 if (conn->task == NULL) {
1417 spin_unlock_bh(&conn->session->back_lock);
1418 return -ENODATA;
1419 }
1420 __iscsi_get_task(task);
1421 spin_unlock_bh(&conn->session->back_lock);
1422 spin_unlock_bh(&conn->session->frwd_lock);
1423 rc = conn->session->tt->xmit_task(task);
1424 spin_lock_bh(&conn->session->frwd_lock);
1425 if (!rc) {
1426 /* done with this task */
1427 task->last_xfer = jiffies;
1428 conn->task = NULL;
1429 }
1430 /* regular RX path uses back_lock */
1431 spin_lock(&conn->session->back_lock);
1432 __iscsi_put_task(task);
1433 spin_unlock(&conn->session->back_lock);
1434 return rc;
1435 }
1436
1437 /**
1438 * iscsi_requeue_task - requeue task to run from session workqueue
1439 * @task: task to requeue
1440 *
1441 * LLDs that need to run a task from the session workqueue should call
1442 * this. The session frwd_lock must be held. This should only be called
1443 * by software drivers.
1444 */
1445 void iscsi_requeue_task(struct iscsi_task *task)
1446 {
1447 struct iscsi_conn *conn = task->conn;
1448
1449 /*
1450 * this may be on the requeue list already if the xmit_task callout
1451 * is handling the r2ts while we are adding new ones
1452 */
1453 spin_lock_bh(&conn->taskqueuelock);
1454 if (list_empty(&task->running))
1455 list_add_tail(&task->running, &conn->requeue);
1456 spin_unlock_bh(&conn->taskqueuelock);
1457 iscsi_conn_queue_work(conn);
1458 }
1459 EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1460
1461 /**
1462 * iscsi_data_xmit - xmit any command into the scheduled connection
1463 * @conn: iscsi connection
1464 *
1465 * Notes:
1466 * The function can return -EAGAIN in which case the caller must
1467 * re-schedule it again later or recover. '0' return code means
1468 * successful xmit.
1469 **/
1470 static int iscsi_data_xmit(struct iscsi_conn *conn)
1471 {
1472 struct iscsi_task *task;
1473 int rc = 0;
1474
1475 spin_lock_bh(&conn->session->frwd_lock);
1476 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1477 ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1478 spin_unlock_bh(&conn->session->frwd_lock);
1479 return -ENODATA;
1480 }
1481
1482 if (conn->task) {
1483 rc = iscsi_xmit_task(conn);
1484 if (rc)
1485 goto done;
1486 }
1487
1488 /*
1489 * process mgmt pdus like nops before commands since we should
1490 * only have one nop-out as a ping from us and targets should not
1491 * overflow us with nop-ins
1492 */
1493 spin_lock_bh(&conn->taskqueuelock);
1494 check_mgmt:
1495 while (!list_empty(&conn->mgmtqueue)) {
1496 conn->task = list_entry(conn->mgmtqueue.next,
1497 struct iscsi_task, running);
1498 list_del_init(&conn->task->running);
1499 spin_unlock_bh(&conn->taskqueuelock);
1500 if (iscsi_prep_mgmt_task(conn, conn->task)) {
1501 /* regular RX path uses back_lock */
1502 spin_lock_bh(&conn->session->back_lock);
1503 __iscsi_put_task(conn->task);
1504 spin_unlock_bh(&conn->session->back_lock);
1505 conn->task = NULL;
1506 spin_lock_bh(&conn->taskqueuelock);
1507 continue;
1508 }
1509 rc = iscsi_xmit_task(conn);
1510 if (rc)
1511 goto done;
1512 spin_lock_bh(&conn->taskqueuelock);
1513 }
1514
1515 /* process pending command queue */
1516 while (!list_empty(&conn->cmdqueue)) {
1517 conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1518 running);
1519 list_del_init(&conn->task->running);
1520 spin_unlock_bh(&conn->taskqueuelock);
1521 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1522 fail_scsi_task(conn->task, DID_IMM_RETRY);
1523 spin_lock_bh(&conn->taskqueuelock);
1524 continue;
1525 }
1526 rc = iscsi_prep_scsi_cmd_pdu(conn->task);
1527 if (rc) {
1528 if (rc == -ENOMEM || rc == -EACCES) {
1529 spin_lock_bh(&conn->taskqueuelock);
1530 list_add_tail(&conn->task->running,
1531 &conn->cmdqueue);
1532 conn->task = NULL;
1533 spin_unlock_bh(&conn->taskqueuelock);
1534 goto done;
1535 } else
1536 fail_scsi_task(conn->task, DID_ABORT);
1537 spin_lock_bh(&conn->taskqueuelock);
1538 continue;
1539 }
1540 rc = iscsi_xmit_task(conn);
1541 if (rc)
1542 goto done;
1543 /*
1544 * we could continuously get new task requests so
1545 * we need to check the mgmt queue for nops that need to
1546 * be sent to aviod starvation
1547 */
1548 spin_lock_bh(&conn->taskqueuelock);
1549 if (!list_empty(&conn->mgmtqueue))
1550 goto check_mgmt;
1551 }
1552
1553 while (!list_empty(&conn->requeue)) {
1554 /*
1555 * we always do fastlogout - conn stop code will clean up.
1556 */
1557 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1558 break;
1559
1560 task = list_entry(conn->requeue.next, struct iscsi_task,
1561 running);
1562 if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1563 break;
1564
1565 conn->task = task;
1566 list_del_init(&conn->task->running);
1567 conn->task->state = ISCSI_TASK_RUNNING;
1568 spin_unlock_bh(&conn->taskqueuelock);
1569 rc = iscsi_xmit_task(conn);
1570 if (rc)
1571 goto done;
1572 spin_lock_bh(&conn->taskqueuelock);
1573 if (!list_empty(&conn->mgmtqueue))
1574 goto check_mgmt;
1575 }
1576 spin_unlock_bh(&conn->taskqueuelock);
1577 spin_unlock_bh(&conn->session->frwd_lock);
1578 return -ENODATA;
1579
1580 done:
1581 spin_unlock_bh(&conn->session->frwd_lock);
1582 return rc;
1583 }
1584
1585 static void iscsi_xmitworker(struct work_struct *work)
1586 {
1587 struct iscsi_conn *conn =
1588 container_of(work, struct iscsi_conn, xmitwork);
1589 int rc;
1590 /*
1591 * serialize Xmit worker on a per-connection basis.
1592 */
1593 do {
1594 rc = iscsi_data_xmit(conn);
1595 } while (rc >= 0 || rc == -EAGAIN);
1596 }
1597
1598 static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1599 struct scsi_cmnd *sc)
1600 {
1601 struct iscsi_task *task;
1602
1603 if (!kfifo_out(&conn->session->cmdpool.queue,
1604 (void *) &task, sizeof(void *)))
1605 return NULL;
1606
1607 sc->SCp.phase = conn->session->age;
1608 sc->SCp.ptr = (char *) task;
1609
1610 refcount_set(&task->refcount, 1);
1611 task->state = ISCSI_TASK_PENDING;
1612 task->conn = conn;
1613 task->sc = sc;
1614 task->have_checked_conn = false;
1615 task->last_timeout = jiffies;
1616 task->last_xfer = jiffies;
1617 task->protected = false;
1618 INIT_LIST_HEAD(&task->running);
1619 return task;
1620 }
1621
1622 enum {
1623 FAILURE_BAD_HOST = 1,
1624 FAILURE_SESSION_FAILED,
1625 FAILURE_SESSION_FREED,
1626 FAILURE_WINDOW_CLOSED,
1627 FAILURE_OOM,
1628 FAILURE_SESSION_TERMINATE,
1629 FAILURE_SESSION_IN_RECOVERY,
1630 FAILURE_SESSION_RECOVERY_TIMEOUT,
1631 FAILURE_SESSION_LOGGING_OUT,
1632 FAILURE_SESSION_NOT_READY,
1633 };
1634
1635 int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1636 {
1637 struct iscsi_cls_session *cls_session;
1638 struct iscsi_host *ihost;
1639 int reason = 0;
1640 struct iscsi_session *session;
1641 struct iscsi_conn *conn;
1642 struct iscsi_task *task = NULL;
1643
1644 sc->result = 0;
1645 sc->SCp.ptr = NULL;
1646
1647 ihost = shost_priv(host);
1648
1649 cls_session = starget_to_session(scsi_target(sc->device));
1650 session = cls_session->dd_data;
1651 spin_lock_bh(&session->frwd_lock);
1652
1653 reason = iscsi_session_chkready(cls_session);
1654 if (reason) {
1655 sc->result = reason;
1656 goto fault;
1657 }
1658
1659 if (session->state != ISCSI_STATE_LOGGED_IN) {
1660 /*
1661 * to handle the race between when we set the recovery state
1662 * and block the session we requeue here (commands could
1663 * be entering our queuecommand while a block is starting
1664 * up because the block code is not locked)
1665 */
1666 switch (session->state) {
1667 case ISCSI_STATE_FAILED:
1668 /*
1669 * cmds should fail during shutdown, if the session
1670 * state is bad, allowing completion to happen
1671 */
1672 if (unlikely(system_state != SYSTEM_RUNNING)) {
1673 reason = FAILURE_SESSION_FAILED;
1674 sc->result = DID_NO_CONNECT << 16;
1675 break;
1676 }
1677 /* fall through */
1678 case ISCSI_STATE_IN_RECOVERY:
1679 reason = FAILURE_SESSION_IN_RECOVERY;
1680 sc->result = DID_IMM_RETRY << 16;
1681 break;
1682 case ISCSI_STATE_LOGGING_OUT:
1683 reason = FAILURE_SESSION_LOGGING_OUT;
1684 sc->result = DID_IMM_RETRY << 16;
1685 break;
1686 case ISCSI_STATE_RECOVERY_FAILED:
1687 reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1688 sc->result = DID_TRANSPORT_FAILFAST << 16;
1689 break;
1690 case ISCSI_STATE_TERMINATE:
1691 reason = FAILURE_SESSION_TERMINATE;
1692 sc->result = DID_NO_CONNECT << 16;
1693 break;
1694 default:
1695 reason = FAILURE_SESSION_FREED;
1696 sc->result = DID_NO_CONNECT << 16;
1697 }
1698 goto fault;
1699 }
1700
1701 conn = session->leadconn;
1702 if (!conn) {
1703 reason = FAILURE_SESSION_FREED;
1704 sc->result = DID_NO_CONNECT << 16;
1705 goto fault;
1706 }
1707
1708 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1709 reason = FAILURE_SESSION_IN_RECOVERY;
1710 sc->result = DID_REQUEUE << 16;
1711 goto fault;
1712 }
1713
1714 if (iscsi_check_cmdsn_window_closed(conn)) {
1715 reason = FAILURE_WINDOW_CLOSED;
1716 goto reject;
1717 }
1718
1719 task = iscsi_alloc_task(conn, sc);
1720 if (!task) {
1721 reason = FAILURE_OOM;
1722 goto reject;
1723 }
1724
1725 if (!ihost->workq) {
1726 reason = iscsi_prep_scsi_cmd_pdu(task);
1727 if (reason) {
1728 if (reason == -ENOMEM || reason == -EACCES) {
1729 reason = FAILURE_OOM;
1730 goto prepd_reject;
1731 } else {
1732 sc->result = DID_ABORT << 16;
1733 goto prepd_fault;
1734 }
1735 }
1736 if (session->tt->xmit_task(task)) {
1737 session->cmdsn--;
1738 reason = FAILURE_SESSION_NOT_READY;
1739 goto prepd_reject;
1740 }
1741 } else {
1742 spin_lock_bh(&conn->taskqueuelock);
1743 list_add_tail(&task->running, &conn->cmdqueue);
1744 spin_unlock_bh(&conn->taskqueuelock);
1745 iscsi_conn_queue_work(conn);
1746 }
1747
1748 session->queued_cmdsn++;
1749 spin_unlock_bh(&session->frwd_lock);
1750 return 0;
1751
1752 prepd_reject:
1753 spin_lock_bh(&session->back_lock);
1754 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1755 spin_unlock_bh(&session->back_lock);
1756 reject:
1757 spin_unlock_bh(&session->frwd_lock);
1758 ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1759 sc->cmnd[0], reason);
1760 return SCSI_MLQUEUE_TARGET_BUSY;
1761
1762 prepd_fault:
1763 spin_lock_bh(&session->back_lock);
1764 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1765 spin_unlock_bh(&session->back_lock);
1766 fault:
1767 spin_unlock_bh(&session->frwd_lock);
1768 ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1769 sc->cmnd[0], reason);
1770 scsi_set_resid(sc, scsi_bufflen(sc));
1771 sc->scsi_done(sc);
1772 return 0;
1773 }
1774 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1775
1776 int iscsi_target_alloc(struct scsi_target *starget)
1777 {
1778 struct iscsi_cls_session *cls_session = starget_to_session(starget);
1779 struct iscsi_session *session = cls_session->dd_data;
1780
1781 starget->can_queue = session->scsi_cmds_max;
1782 return 0;
1783 }
1784 EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1785
1786 static void iscsi_tmf_timedout(struct timer_list *t)
1787 {
1788 struct iscsi_conn *conn = from_timer(conn, t, tmf_timer);
1789 struct iscsi_session *session = conn->session;
1790
1791 spin_lock(&session->frwd_lock);
1792 if (conn->tmf_state == TMF_QUEUED) {
1793 conn->tmf_state = TMF_TIMEDOUT;
1794 ISCSI_DBG_EH(session, "tmf timedout\n");
1795 /* unblock eh_abort() */
1796 wake_up(&conn->ehwait);
1797 }
1798 spin_unlock(&session->frwd_lock);
1799 }
1800
1801 static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1802 struct iscsi_tm *hdr, int age,
1803 int timeout)
1804 __must_hold(&session->frwd_lock)
1805 {
1806 struct iscsi_session *session = conn->session;
1807 struct iscsi_task *task;
1808
1809 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1810 NULL, 0);
1811 if (!task) {
1812 spin_unlock_bh(&session->frwd_lock);
1813 iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1814 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1815 spin_lock_bh(&session->frwd_lock);
1816 return -EPERM;
1817 }
1818 conn->tmfcmd_pdus_cnt++;
1819 conn->tmf_timer.expires = timeout * HZ + jiffies;
1820 add_timer(&conn->tmf_timer);
1821 ISCSI_DBG_EH(session, "tmf set timeout\n");
1822
1823 spin_unlock_bh(&session->frwd_lock);
1824 mutex_unlock(&session->eh_mutex);
1825
1826 /*
1827 * block eh thread until:
1828 *
1829 * 1) tmf response
1830 * 2) tmf timeout
1831 * 3) session is terminated or restarted or userspace has
1832 * given up on recovery
1833 */
1834 wait_event_interruptible(conn->ehwait, age != session->age ||
1835 session->state != ISCSI_STATE_LOGGED_IN ||
1836 conn->tmf_state != TMF_QUEUED);
1837 if (signal_pending(current))
1838 flush_signals(current);
1839 del_timer_sync(&conn->tmf_timer);
1840
1841 mutex_lock(&session->eh_mutex);
1842 spin_lock_bh(&session->frwd_lock);
1843 /* if the session drops it will clean up the task */
1844 if (age != session->age ||
1845 session->state != ISCSI_STATE_LOGGED_IN)
1846 return -ENOTCONN;
1847 return 0;
1848 }
1849
1850 /*
1851 * Fail commands. session lock held and recv side suspended and xmit
1852 * thread flushed
1853 */
1854 static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error)
1855 {
1856 struct iscsi_task *task;
1857 int i;
1858
1859 for (i = 0; i < conn->session->cmds_max; i++) {
1860 task = conn->session->cmds[i];
1861 if (!task->sc || task->state == ISCSI_TASK_FREE)
1862 continue;
1863
1864 if (lun != -1 && lun != task->sc->device->lun)
1865 continue;
1866
1867 ISCSI_DBG_SESSION(conn->session,
1868 "failing sc %p itt 0x%x state %d\n",
1869 task->sc, task->itt, task->state);
1870 fail_scsi_task(task, error);
1871 }
1872 }
1873
1874 /**
1875 * iscsi_suspend_queue - suspend iscsi_queuecommand
1876 * @conn: iscsi conn to stop queueing IO on
1877 *
1878 * This grabs the session frwd_lock to make sure no one is in
1879 * xmit_task/queuecommand, and then sets suspend to prevent
1880 * new commands from being queued. This only needs to be called
1881 * by offload drivers that need to sync a path like ep disconnect
1882 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1883 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1884 */
1885 void iscsi_suspend_queue(struct iscsi_conn *conn)
1886 {
1887 spin_lock_bh(&conn->session->frwd_lock);
1888 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1889 spin_unlock_bh(&conn->session->frwd_lock);
1890 }
1891 EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1892
1893 /**
1894 * iscsi_suspend_tx - suspend iscsi_data_xmit
1895 * @conn: iscsi conn tp stop processing IO on.
1896 *
1897 * This function sets the suspend bit to prevent iscsi_data_xmit
1898 * from sending new IO, and if work is queued on the xmit thread
1899 * it will wait for it to be completed.
1900 */
1901 void iscsi_suspend_tx(struct iscsi_conn *conn)
1902 {
1903 struct Scsi_Host *shost = conn->session->host;
1904 struct iscsi_host *ihost = shost_priv(shost);
1905
1906 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1907 if (ihost->workq)
1908 flush_workqueue(ihost->workq);
1909 }
1910 EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1911
1912 static void iscsi_start_tx(struct iscsi_conn *conn)
1913 {
1914 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1915 iscsi_conn_queue_work(conn);
1916 }
1917
1918 /*
1919 * We want to make sure a ping is in flight. It has timed out.
1920 * And we are not busy processing a pdu that is making
1921 * progress but got started before the ping and is taking a while
1922 * to complete so the ping is just stuck behind it in a queue.
1923 */
1924 static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1925 {
1926 if (conn->ping_task &&
1927 time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1928 (conn->ping_timeout * HZ), jiffies))
1929 return 1;
1930 else
1931 return 0;
1932 }
1933
1934 enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1935 {
1936 enum blk_eh_timer_return rc = BLK_EH_DONE;
1937 struct iscsi_task *task = NULL, *running_task;
1938 struct iscsi_cls_session *cls_session;
1939 struct iscsi_session *session;
1940 struct iscsi_conn *conn;
1941 int i;
1942
1943 cls_session = starget_to_session(scsi_target(sc->device));
1944 session = cls_session->dd_data;
1945
1946 ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1947
1948 spin_lock_bh(&session->frwd_lock);
1949 task = (struct iscsi_task *)sc->SCp.ptr;
1950 if (!task) {
1951 /*
1952 * Raced with completion. Blk layer has taken ownership
1953 * so let timeout code complete it now.
1954 */
1955 rc = BLK_EH_DONE;
1956 goto done;
1957 }
1958
1959 if (session->state != ISCSI_STATE_LOGGED_IN) {
1960 /*
1961 * During shutdown, if session is prematurely disconnected,
1962 * recovery won't happen and there will be hung cmds. Not
1963 * handling cmds would trigger EH, also bad in this case.
1964 * Instead, handle cmd, allow completion to happen and let
1965 * upper layer to deal with the result.
1966 */
1967 if (unlikely(system_state != SYSTEM_RUNNING)) {
1968 sc->result = DID_NO_CONNECT << 16;
1969 ISCSI_DBG_EH(session, "sc on shutdown, handled\n");
1970 rc = BLK_EH_DONE;
1971 goto done;
1972 }
1973 /*
1974 * We are probably in the middle of iscsi recovery so let
1975 * that complete and handle the error.
1976 */
1977 rc = BLK_EH_RESET_TIMER;
1978 goto done;
1979 }
1980
1981 conn = session->leadconn;
1982 if (!conn) {
1983 /* In the middle of shuting down */
1984 rc = BLK_EH_RESET_TIMER;
1985 goto done;
1986 }
1987
1988 /*
1989 * If we have sent (at least queued to the network layer) a pdu or
1990 * recvd one for the task since the last timeout ask for
1991 * more time. If on the next timeout we have not made progress
1992 * we can check if it is the task or connection when we send the
1993 * nop as a ping.
1994 */
1995 if (time_after(task->last_xfer, task->last_timeout)) {
1996 ISCSI_DBG_EH(session, "Command making progress. Asking "
1997 "scsi-ml for more time to complete. "
1998 "Last data xfer at %lu. Last timeout was at "
1999 "%lu\n.", task->last_xfer, task->last_timeout);
2000 task->have_checked_conn = false;
2001 rc = BLK_EH_RESET_TIMER;
2002 goto done;
2003 }
2004
2005 if (!conn->recv_timeout && !conn->ping_timeout)
2006 goto done;
2007 /*
2008 * if the ping timedout then we are in the middle of cleaning up
2009 * and can let the iscsi eh handle it
2010 */
2011 if (iscsi_has_ping_timed_out(conn)) {
2012 rc = BLK_EH_RESET_TIMER;
2013 goto done;
2014 }
2015
2016 for (i = 0; i < conn->session->cmds_max; i++) {
2017 running_task = conn->session->cmds[i];
2018 if (!running_task->sc || running_task == task ||
2019 running_task->state != ISCSI_TASK_RUNNING)
2020 continue;
2021
2022 /*
2023 * Only check if cmds started before this one have made
2024 * progress, or this could never fail
2025 */
2026 if (time_after(running_task->sc->jiffies_at_alloc,
2027 task->sc->jiffies_at_alloc))
2028 continue;
2029
2030 if (time_after(running_task->last_xfer, task->last_timeout)) {
2031 /*
2032 * This task has not made progress, but a task
2033 * started before us has transferred data since
2034 * we started/last-checked. We could be queueing
2035 * too many tasks or the LU is bad.
2036 *
2037 * If the device is bad the cmds ahead of us on
2038 * other devs will complete, and this loop will
2039 * eventually fail starting the scsi eh.
2040 */
2041 ISCSI_DBG_EH(session, "Command has not made progress "
2042 "but commands ahead of it have. "
2043 "Asking scsi-ml for more time to "
2044 "complete. Our last xfer vs running task "
2045 "last xfer %lu/%lu. Last check %lu.\n",
2046 task->last_xfer, running_task->last_xfer,
2047 task->last_timeout);
2048 rc = BLK_EH_RESET_TIMER;
2049 goto done;
2050 }
2051 }
2052
2053 /* Assumes nop timeout is shorter than scsi cmd timeout */
2054 if (task->have_checked_conn)
2055 goto done;
2056
2057 /*
2058 * Checking the transport already or nop from a cmd timeout still
2059 * running
2060 */
2061 if (conn->ping_task) {
2062 task->have_checked_conn = true;
2063 rc = BLK_EH_RESET_TIMER;
2064 goto done;
2065 }
2066
2067 /* Make sure there is a transport check done */
2068 iscsi_send_nopout(conn, NULL);
2069 task->have_checked_conn = true;
2070 rc = BLK_EH_RESET_TIMER;
2071
2072 done:
2073 if (task)
2074 task->last_timeout = jiffies;
2075 spin_unlock_bh(&session->frwd_lock);
2076 ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2077 "timer reset" : "shutdown or nh");
2078 return rc;
2079 }
2080 EXPORT_SYMBOL_GPL(iscsi_eh_cmd_timed_out);
2081
2082 static void iscsi_check_transport_timeouts(struct timer_list *t)
2083 {
2084 struct iscsi_conn *conn = from_timer(conn, t, transport_timer);
2085 struct iscsi_session *session = conn->session;
2086 unsigned long recv_timeout, next_timeout = 0, last_recv;
2087
2088 spin_lock(&session->frwd_lock);
2089 if (session->state != ISCSI_STATE_LOGGED_IN)
2090 goto done;
2091
2092 recv_timeout = conn->recv_timeout;
2093 if (!recv_timeout)
2094 goto done;
2095
2096 recv_timeout *= HZ;
2097 last_recv = conn->last_recv;
2098
2099 if (iscsi_has_ping_timed_out(conn)) {
2100 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2101 "expired, recv timeout %d, last rx %lu, "
2102 "last ping %lu, now %lu\n",
2103 conn->ping_timeout, conn->recv_timeout,
2104 last_recv, conn->last_ping, jiffies);
2105 spin_unlock(&session->frwd_lock);
2106 iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT);
2107 return;
2108 }
2109
2110 if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2111 /* send a ping to try to provoke some traffic */
2112 ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2113 if (iscsi_send_nopout(conn, NULL))
2114 next_timeout = jiffies + (1 * HZ);
2115 else
2116 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2117 } else
2118 next_timeout = last_recv + recv_timeout;
2119
2120 ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2121 mod_timer(&conn->transport_timer, next_timeout);
2122 done:
2123 spin_unlock(&session->frwd_lock);
2124 }
2125
2126 static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2127 struct iscsi_tm *hdr)
2128 {
2129 memset(hdr, 0, sizeof(*hdr));
2130 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2131 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2132 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2133 hdr->lun = task->lun;
2134 hdr->rtt = task->hdr_itt;
2135 hdr->refcmdsn = task->cmdsn;
2136 }
2137
2138 int iscsi_eh_abort(struct scsi_cmnd *sc)
2139 {
2140 struct iscsi_cls_session *cls_session;
2141 struct iscsi_session *session;
2142 struct iscsi_conn *conn;
2143 struct iscsi_task *task;
2144 struct iscsi_tm *hdr;
2145 int age;
2146
2147 cls_session = starget_to_session(scsi_target(sc->device));
2148 session = cls_session->dd_data;
2149
2150 ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2151
2152 mutex_lock(&session->eh_mutex);
2153 spin_lock_bh(&session->frwd_lock);
2154 /*
2155 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2156 * got the command.
2157 */
2158 if (!sc->SCp.ptr) {
2159 ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2160 "it completed.\n");
2161 spin_unlock_bh(&session->frwd_lock);
2162 mutex_unlock(&session->eh_mutex);
2163 return SUCCESS;
2164 }
2165
2166 /*
2167 * If we are not logged in or we have started a new session
2168 * then let the host reset code handle this
2169 */
2170 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2171 sc->SCp.phase != session->age) {
2172 spin_unlock_bh(&session->frwd_lock);
2173 mutex_unlock(&session->eh_mutex);
2174 ISCSI_DBG_EH(session, "failing abort due to dropped "
2175 "session.\n");
2176 return FAILED;
2177 }
2178
2179 conn = session->leadconn;
2180 conn->eh_abort_cnt++;
2181 age = session->age;
2182
2183 task = (struct iscsi_task *)sc->SCp.ptr;
2184 ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
2185 sc, task->itt);
2186
2187 /* task completed before time out */
2188 if (!task->sc) {
2189 ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2190 goto success;
2191 }
2192
2193 if (task->state == ISCSI_TASK_PENDING) {
2194 fail_scsi_task(task, DID_ABORT);
2195 goto success;
2196 }
2197
2198 /* only have one tmf outstanding at a time */
2199 if (conn->tmf_state != TMF_INITIAL)
2200 goto failed;
2201 conn->tmf_state = TMF_QUEUED;
2202
2203 hdr = &conn->tmhdr;
2204 iscsi_prep_abort_task_pdu(task, hdr);
2205
2206 if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout))
2207 goto failed;
2208
2209 switch (conn->tmf_state) {
2210 case TMF_SUCCESS:
2211 spin_unlock_bh(&session->frwd_lock);
2212 /*
2213 * stop tx side incase the target had sent a abort rsp but
2214 * the initiator was still writing out data.
2215 */
2216 iscsi_suspend_tx(conn);
2217 /*
2218 * we do not stop the recv side because targets have been
2219 * good and have never sent us a successful tmf response
2220 * then sent more data for the cmd.
2221 */
2222 spin_lock_bh(&session->frwd_lock);
2223 fail_scsi_task(task, DID_ABORT);
2224 conn->tmf_state = TMF_INITIAL;
2225 memset(hdr, 0, sizeof(*hdr));
2226 spin_unlock_bh(&session->frwd_lock);
2227 iscsi_start_tx(conn);
2228 goto success_unlocked;
2229 case TMF_TIMEDOUT:
2230 spin_unlock_bh(&session->frwd_lock);
2231 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2232 goto failed_unlocked;
2233 case TMF_NOT_FOUND:
2234 if (!sc->SCp.ptr) {
2235 conn->tmf_state = TMF_INITIAL;
2236 memset(hdr, 0, sizeof(*hdr));
2237 /* task completed before tmf abort response */
2238 ISCSI_DBG_EH(session, "sc completed while abort in "
2239 "progress\n");
2240 goto success;
2241 }
2242 /* fall through */
2243 default:
2244 conn->tmf_state = TMF_INITIAL;
2245 goto failed;
2246 }
2247
2248 success:
2249 spin_unlock_bh(&session->frwd_lock);
2250 success_unlocked:
2251 ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2252 sc, task->itt);
2253 mutex_unlock(&session->eh_mutex);
2254 return SUCCESS;
2255
2256 failed:
2257 spin_unlock_bh(&session->frwd_lock);
2258 failed_unlocked:
2259 ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2260 task ? task->itt : 0);
2261 mutex_unlock(&session->eh_mutex);
2262 return FAILED;
2263 }
2264 EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2265
2266 static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2267 {
2268 memset(hdr, 0, sizeof(*hdr));
2269 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2270 hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2271 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2272 int_to_scsilun(sc->device->lun, &hdr->lun);
2273 hdr->rtt = RESERVED_ITT;
2274 }
2275
2276 int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2277 {
2278 struct iscsi_cls_session *cls_session;
2279 struct iscsi_session *session;
2280 struct iscsi_conn *conn;
2281 struct iscsi_tm *hdr;
2282 int rc = FAILED;
2283
2284 cls_session = starget_to_session(scsi_target(sc->device));
2285 session = cls_session->dd_data;
2286
2287 ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc,
2288 sc->device->lun);
2289
2290 mutex_lock(&session->eh_mutex);
2291 spin_lock_bh(&session->frwd_lock);
2292 /*
2293 * Just check if we are not logged in. We cannot check for
2294 * the phase because the reset could come from a ioctl.
2295 */
2296 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2297 goto unlock;
2298 conn = session->leadconn;
2299
2300 /* only have one tmf outstanding at a time */
2301 if (conn->tmf_state != TMF_INITIAL)
2302 goto unlock;
2303 conn->tmf_state = TMF_QUEUED;
2304
2305 hdr = &conn->tmhdr;
2306 iscsi_prep_lun_reset_pdu(sc, hdr);
2307
2308 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2309 session->lu_reset_timeout)) {
2310 rc = FAILED;
2311 goto unlock;
2312 }
2313
2314 switch (conn->tmf_state) {
2315 case TMF_SUCCESS:
2316 break;
2317 case TMF_TIMEDOUT:
2318 spin_unlock_bh(&session->frwd_lock);
2319 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2320 goto done;
2321 default:
2322 conn->tmf_state = TMF_INITIAL;
2323 goto unlock;
2324 }
2325
2326 rc = SUCCESS;
2327 spin_unlock_bh(&session->frwd_lock);
2328
2329 iscsi_suspend_tx(conn);
2330
2331 spin_lock_bh(&session->frwd_lock);
2332 memset(hdr, 0, sizeof(*hdr));
2333 fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2334 conn->tmf_state = TMF_INITIAL;
2335 spin_unlock_bh(&session->frwd_lock);
2336
2337 iscsi_start_tx(conn);
2338 goto done;
2339
2340 unlock:
2341 spin_unlock_bh(&session->frwd_lock);
2342 done:
2343 ISCSI_DBG_EH(session, "dev reset result = %s\n",
2344 rc == SUCCESS ? "SUCCESS" : "FAILED");
2345 mutex_unlock(&session->eh_mutex);
2346 return rc;
2347 }
2348 EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2349
2350 void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2351 {
2352 struct iscsi_session *session = cls_session->dd_data;
2353
2354 spin_lock_bh(&session->frwd_lock);
2355 if (session->state != ISCSI_STATE_LOGGED_IN) {
2356 session->state = ISCSI_STATE_RECOVERY_FAILED;
2357 if (session->leadconn)
2358 wake_up(&session->leadconn->ehwait);
2359 }
2360 spin_unlock_bh(&session->frwd_lock);
2361 }
2362 EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2363
2364 /**
2365 * iscsi_eh_session_reset - drop session and attempt relogin
2366 * @sc: scsi command
2367 *
2368 * This function will wait for a relogin, session termination from
2369 * userspace, or a recovery/replacement timeout.
2370 */
2371 int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2372 {
2373 struct iscsi_cls_session *cls_session;
2374 struct iscsi_session *session;
2375 struct iscsi_conn *conn;
2376
2377 cls_session = starget_to_session(scsi_target(sc->device));
2378 session = cls_session->dd_data;
2379 conn = session->leadconn;
2380
2381 mutex_lock(&session->eh_mutex);
2382 spin_lock_bh(&session->frwd_lock);
2383 if (session->state == ISCSI_STATE_TERMINATE) {
2384 failed:
2385 ISCSI_DBG_EH(session,
2386 "failing session reset: Could not log back into "
2387 "%s [age %d]\n", session->targetname,
2388 session->age);
2389 spin_unlock_bh(&session->frwd_lock);
2390 mutex_unlock(&session->eh_mutex);
2391 return FAILED;
2392 }
2393
2394 spin_unlock_bh(&session->frwd_lock);
2395 mutex_unlock(&session->eh_mutex);
2396 /*
2397 * we drop the lock here but the leadconn cannot be destoyed while
2398 * we are in the scsi eh
2399 */
2400 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2401
2402 ISCSI_DBG_EH(session, "wait for relogin\n");
2403 wait_event_interruptible(conn->ehwait,
2404 session->state == ISCSI_STATE_TERMINATE ||
2405 session->state == ISCSI_STATE_LOGGED_IN ||
2406 session->state == ISCSI_STATE_RECOVERY_FAILED);
2407 if (signal_pending(current))
2408 flush_signals(current);
2409
2410 mutex_lock(&session->eh_mutex);
2411 spin_lock_bh(&session->frwd_lock);
2412 if (session->state == ISCSI_STATE_LOGGED_IN) {
2413 ISCSI_DBG_EH(session,
2414 "session reset succeeded for %s,%s\n",
2415 session->targetname, conn->persistent_address);
2416 } else
2417 goto failed;
2418 spin_unlock_bh(&session->frwd_lock);
2419 mutex_unlock(&session->eh_mutex);
2420 return SUCCESS;
2421 }
2422 EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2423
2424 static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2425 {
2426 memset(hdr, 0, sizeof(*hdr));
2427 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2428 hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2429 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2430 hdr->rtt = RESERVED_ITT;
2431 }
2432
2433 /**
2434 * iscsi_eh_target_reset - reset target
2435 * @sc: scsi command
2436 *
2437 * This will attempt to send a warm target reset.
2438 */
2439 static int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2440 {
2441 struct iscsi_cls_session *cls_session;
2442 struct iscsi_session *session;
2443 struct iscsi_conn *conn;
2444 struct iscsi_tm *hdr;
2445 int rc = FAILED;
2446
2447 cls_session = starget_to_session(scsi_target(sc->device));
2448 session = cls_session->dd_data;
2449
2450 ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2451 session->targetname);
2452
2453 mutex_lock(&session->eh_mutex);
2454 spin_lock_bh(&session->frwd_lock);
2455 /*
2456 * Just check if we are not logged in. We cannot check for
2457 * the phase because the reset could come from a ioctl.
2458 */
2459 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2460 goto unlock;
2461 conn = session->leadconn;
2462
2463 /* only have one tmf outstanding at a time */
2464 if (conn->tmf_state != TMF_INITIAL)
2465 goto unlock;
2466 conn->tmf_state = TMF_QUEUED;
2467
2468 hdr = &conn->tmhdr;
2469 iscsi_prep_tgt_reset_pdu(sc, hdr);
2470
2471 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2472 session->tgt_reset_timeout)) {
2473 rc = FAILED;
2474 goto unlock;
2475 }
2476
2477 switch (conn->tmf_state) {
2478 case TMF_SUCCESS:
2479 break;
2480 case TMF_TIMEDOUT:
2481 spin_unlock_bh(&session->frwd_lock);
2482 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2483 goto done;
2484 default:
2485 conn->tmf_state = TMF_INITIAL;
2486 goto unlock;
2487 }
2488
2489 rc = SUCCESS;
2490 spin_unlock_bh(&session->frwd_lock);
2491
2492 iscsi_suspend_tx(conn);
2493
2494 spin_lock_bh(&session->frwd_lock);
2495 memset(hdr, 0, sizeof(*hdr));
2496 fail_scsi_tasks(conn, -1, DID_ERROR);
2497 conn->tmf_state = TMF_INITIAL;
2498 spin_unlock_bh(&session->frwd_lock);
2499
2500 iscsi_start_tx(conn);
2501 goto done;
2502
2503 unlock:
2504 spin_unlock_bh(&session->frwd_lock);
2505 done:
2506 ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2507 rc == SUCCESS ? "SUCCESS" : "FAILED");
2508 mutex_unlock(&session->eh_mutex);
2509 return rc;
2510 }
2511
2512 /**
2513 * iscsi_eh_recover_target - reset target and possibly the session
2514 * @sc: scsi command
2515 *
2516 * This will attempt to send a warm target reset. If that fails,
2517 * we will escalate to ERL0 session recovery.
2518 */
2519 int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2520 {
2521 int rc;
2522
2523 rc = iscsi_eh_target_reset(sc);
2524 if (rc == FAILED)
2525 rc = iscsi_eh_session_reset(sc);
2526 return rc;
2527 }
2528 EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2529
2530 /*
2531 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2532 * should be accessed via kfifo_{get,put} on q->queue.
2533 * Optionally, the caller can obtain the array of object pointers
2534 * by passing in a non-NULL @items pointer
2535 */
2536 int
2537 iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2538 {
2539 int i, num_arrays = 1;
2540
2541 memset(q, 0, sizeof(*q));
2542
2543 q->max = max;
2544
2545 /* If the user passed an items pointer, he wants a copy of
2546 * the array. */
2547 if (items)
2548 num_arrays++;
2549 q->pool = kvcalloc(num_arrays * max, sizeof(void *), GFP_KERNEL);
2550 if (q->pool == NULL)
2551 return -ENOMEM;
2552
2553 kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2554
2555 for (i = 0; i < max; i++) {
2556 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2557 if (q->pool[i] == NULL) {
2558 q->max = i;
2559 goto enomem;
2560 }
2561 kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2562 }
2563
2564 if (items) {
2565 *items = q->pool + max;
2566 memcpy(*items, q->pool, max * sizeof(void *));
2567 }
2568
2569 return 0;
2570
2571 enomem:
2572 iscsi_pool_free(q);
2573 return -ENOMEM;
2574 }
2575 EXPORT_SYMBOL_GPL(iscsi_pool_init);
2576
2577 void iscsi_pool_free(struct iscsi_pool *q)
2578 {
2579 int i;
2580
2581 for (i = 0; i < q->max; i++)
2582 kfree(q->pool[i]);
2583 kvfree(q->pool);
2584 }
2585 EXPORT_SYMBOL_GPL(iscsi_pool_free);
2586
2587 /**
2588 * iscsi_host_add - add host to system
2589 * @shost: scsi host
2590 * @pdev: parent device
2591 *
2592 * This should be called by partial offload and software iscsi drivers
2593 * to add a host to the system.
2594 */
2595 int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2596 {
2597 if (!shost->can_queue)
2598 shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2599
2600 if (!shost->cmd_per_lun)
2601 shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2602
2603 return scsi_add_host(shost, pdev);
2604 }
2605 EXPORT_SYMBOL_GPL(iscsi_host_add);
2606
2607 /**
2608 * iscsi_host_alloc - allocate a host and driver data
2609 * @sht: scsi host template
2610 * @dd_data_size: driver host data size
2611 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2612 *
2613 * This should be called by partial offload and software iscsi drivers.
2614 * To access the driver specific memory use the iscsi_host_priv() macro.
2615 */
2616 struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2617 int dd_data_size, bool xmit_can_sleep)
2618 {
2619 struct Scsi_Host *shost;
2620 struct iscsi_host *ihost;
2621
2622 shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2623 if (!shost)
2624 return NULL;
2625 ihost = shost_priv(shost);
2626
2627 if (xmit_can_sleep) {
2628 snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2629 "iscsi_q_%d", shost->host_no);
2630 ihost->workq = create_singlethread_workqueue(ihost->workq_name);
2631 if (!ihost->workq)
2632 goto free_host;
2633 }
2634
2635 spin_lock_init(&ihost->lock);
2636 ihost->state = ISCSI_HOST_SETUP;
2637 ihost->num_sessions = 0;
2638 init_waitqueue_head(&ihost->session_removal_wq);
2639 return shost;
2640
2641 free_host:
2642 scsi_host_put(shost);
2643 return NULL;
2644 }
2645 EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2646
2647 static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2648 {
2649 iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2650 }
2651
2652 /**
2653 * iscsi_host_remove - remove host and sessions
2654 * @shost: scsi host
2655 *
2656 * If there are any sessions left, this will initiate the removal and wait
2657 * for the completion.
2658 */
2659 void iscsi_host_remove(struct Scsi_Host *shost)
2660 {
2661 struct iscsi_host *ihost = shost_priv(shost);
2662 unsigned long flags;
2663
2664 spin_lock_irqsave(&ihost->lock, flags);
2665 ihost->state = ISCSI_HOST_REMOVED;
2666 spin_unlock_irqrestore(&ihost->lock, flags);
2667
2668 iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2669 wait_event_interruptible(ihost->session_removal_wq,
2670 ihost->num_sessions == 0);
2671 if (signal_pending(current))
2672 flush_signals(current);
2673
2674 scsi_remove_host(shost);
2675 if (ihost->workq)
2676 destroy_workqueue(ihost->workq);
2677 }
2678 EXPORT_SYMBOL_GPL(iscsi_host_remove);
2679
2680 void iscsi_host_free(struct Scsi_Host *shost)
2681 {
2682 struct iscsi_host *ihost = shost_priv(shost);
2683
2684 kfree(ihost->netdev);
2685 kfree(ihost->hwaddress);
2686 kfree(ihost->initiatorname);
2687 scsi_host_put(shost);
2688 }
2689 EXPORT_SYMBOL_GPL(iscsi_host_free);
2690
2691 static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2692 {
2693 struct iscsi_host *ihost = shost_priv(shost);
2694 unsigned long flags;
2695
2696 shost = scsi_host_get(shost);
2697 if (!shost) {
2698 printk(KERN_ERR "Invalid state. Cannot notify host removal "
2699 "of session teardown event because host already "
2700 "removed.\n");
2701 return;
2702 }
2703
2704 spin_lock_irqsave(&ihost->lock, flags);
2705 ihost->num_sessions--;
2706 if (ihost->num_sessions == 0)
2707 wake_up(&ihost->session_removal_wq);
2708 spin_unlock_irqrestore(&ihost->lock, flags);
2709 scsi_host_put(shost);
2710 }
2711
2712 /**
2713 * iscsi_session_setup - create iscsi cls session and host and session
2714 * @iscsit: iscsi transport template
2715 * @shost: scsi host
2716 * @cmds_max: session can queue
2717 * @dd_size: private driver data size, added to session allocation size
2718 * @cmd_task_size: LLD task private data size
2719 * @initial_cmdsn: initial CmdSN
2720 * @id: target ID to add to this session
2721 *
2722 * This can be used by software iscsi_transports that allocate
2723 * a session per scsi host.
2724 *
2725 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2726 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2727 * for nop handling and login/logout requests.
2728 */
2729 struct iscsi_cls_session *
2730 iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2731 uint16_t cmds_max, int dd_size, int cmd_task_size,
2732 uint32_t initial_cmdsn, unsigned int id)
2733 {
2734 struct iscsi_host *ihost = shost_priv(shost);
2735 struct iscsi_session *session;
2736 struct iscsi_cls_session *cls_session;
2737 int cmd_i, scsi_cmds, total_cmds = cmds_max;
2738 unsigned long flags;
2739
2740 spin_lock_irqsave(&ihost->lock, flags);
2741 if (ihost->state == ISCSI_HOST_REMOVED) {
2742 spin_unlock_irqrestore(&ihost->lock, flags);
2743 return NULL;
2744 }
2745 ihost->num_sessions++;
2746 spin_unlock_irqrestore(&ihost->lock, flags);
2747
2748 if (!total_cmds)
2749 total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2750 /*
2751 * The iscsi layer needs some tasks for nop handling and tmfs,
2752 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2753 * + 1 command for scsi IO.
2754 */
2755 if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2756 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2757 "must be a power of two that is at least %d.\n",
2758 total_cmds, ISCSI_TOTAL_CMDS_MIN);
2759 goto dec_session_count;
2760 }
2761
2762 if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2763 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2764 "must be a power of 2 less than or equal to %d.\n",
2765 cmds_max, ISCSI_TOTAL_CMDS_MAX);
2766 total_cmds = ISCSI_TOTAL_CMDS_MAX;
2767 }
2768
2769 if (!is_power_of_2(total_cmds)) {
2770 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2771 "must be a power of 2.\n", total_cmds);
2772 total_cmds = rounddown_pow_of_two(total_cmds);
2773 if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
2774 goto dec_session_count;
2775 printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
2776 total_cmds);
2777 }
2778 scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2779
2780 cls_session = iscsi_alloc_session(shost, iscsit,
2781 sizeof(struct iscsi_session) +
2782 dd_size);
2783 if (!cls_session)
2784 goto dec_session_count;
2785 session = cls_session->dd_data;
2786 session->cls_session = cls_session;
2787 session->host = shost;
2788 session->state = ISCSI_STATE_FREE;
2789 session->fast_abort = 1;
2790 session->tgt_reset_timeout = 30;
2791 session->lu_reset_timeout = 15;
2792 session->abort_timeout = 10;
2793 session->scsi_cmds_max = scsi_cmds;
2794 session->cmds_max = total_cmds;
2795 session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2796 session->exp_cmdsn = initial_cmdsn + 1;
2797 session->max_cmdsn = initial_cmdsn + 1;
2798 session->max_r2t = 1;
2799 session->tt = iscsit;
2800 session->dd_data = cls_session->dd_data + sizeof(*session);
2801
2802 mutex_init(&session->eh_mutex);
2803 spin_lock_init(&session->frwd_lock);
2804 spin_lock_init(&session->back_lock);
2805
2806 /* initialize SCSI PDU commands pool */
2807 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2808 (void***)&session->cmds,
2809 cmd_task_size + sizeof(struct iscsi_task)))
2810 goto cmdpool_alloc_fail;
2811
2812 /* pre-format cmds pool with ITT */
2813 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2814 struct iscsi_task *task = session->cmds[cmd_i];
2815
2816 if (cmd_task_size)
2817 task->dd_data = &task[1];
2818 task->itt = cmd_i;
2819 task->state = ISCSI_TASK_FREE;
2820 INIT_LIST_HEAD(&task->running);
2821 }
2822
2823 if (!try_module_get(iscsit->owner))
2824 goto module_get_fail;
2825
2826 if (iscsi_add_session(cls_session, id))
2827 goto cls_session_fail;
2828
2829 return cls_session;
2830
2831 cls_session_fail:
2832 module_put(iscsit->owner);
2833 module_get_fail:
2834 iscsi_pool_free(&session->cmdpool);
2835 cmdpool_alloc_fail:
2836 iscsi_free_session(cls_session);
2837 dec_session_count:
2838 iscsi_host_dec_session_cnt(shost);
2839 return NULL;
2840 }
2841 EXPORT_SYMBOL_GPL(iscsi_session_setup);
2842
2843 /**
2844 * iscsi_session_teardown - destroy session, host, and cls_session
2845 * @cls_session: iscsi session
2846 */
2847 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2848 {
2849 struct iscsi_session *session = cls_session->dd_data;
2850 struct module *owner = cls_session->transport->owner;
2851 struct Scsi_Host *shost = session->host;
2852
2853 iscsi_pool_free(&session->cmdpool);
2854
2855 iscsi_remove_session(cls_session);
2856
2857 kfree(session->password);
2858 kfree(session->password_in);
2859 kfree(session->username);
2860 kfree(session->username_in);
2861 kfree(session->targetname);
2862 kfree(session->targetalias);
2863 kfree(session->initiatorname);
2864 kfree(session->boot_root);
2865 kfree(session->boot_nic);
2866 kfree(session->boot_target);
2867 kfree(session->ifacename);
2868 kfree(session->portal_type);
2869 kfree(session->discovery_parent_type);
2870
2871 iscsi_free_session(cls_session);
2872
2873 iscsi_host_dec_session_cnt(shost);
2874 module_put(owner);
2875 }
2876 EXPORT_SYMBOL_GPL(iscsi_session_teardown);
2877
2878 /**
2879 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
2880 * @cls_session: iscsi_cls_session
2881 * @dd_size: private driver data size
2882 * @conn_idx: cid
2883 */
2884 struct iscsi_cls_conn *
2885 iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2886 uint32_t conn_idx)
2887 {
2888 struct iscsi_session *session = cls_session->dd_data;
2889 struct iscsi_conn *conn;
2890 struct iscsi_cls_conn *cls_conn;
2891 char *data;
2892
2893 cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2894 conn_idx);
2895 if (!cls_conn)
2896 return NULL;
2897 conn = cls_conn->dd_data;
2898 memset(conn, 0, sizeof(*conn) + dd_size);
2899
2900 conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2901 conn->session = session;
2902 conn->cls_conn = cls_conn;
2903 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2904 conn->id = conn_idx;
2905 conn->exp_statsn = 0;
2906 conn->tmf_state = TMF_INITIAL;
2907
2908 timer_setup(&conn->transport_timer, iscsi_check_transport_timeouts, 0);
2909
2910 INIT_LIST_HEAD(&conn->mgmtqueue);
2911 INIT_LIST_HEAD(&conn->cmdqueue);
2912 INIT_LIST_HEAD(&conn->requeue);
2913 spin_lock_init(&conn->taskqueuelock);
2914 INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2915
2916 /* allocate login_task used for the login/text sequences */
2917 spin_lock_bh(&session->frwd_lock);
2918 if (!kfifo_out(&session->cmdpool.queue,
2919 (void*)&conn->login_task,
2920 sizeof(void*))) {
2921 spin_unlock_bh(&session->frwd_lock);
2922 goto login_task_alloc_fail;
2923 }
2924 spin_unlock_bh(&session->frwd_lock);
2925
2926 data = (char *) __get_free_pages(GFP_KERNEL,
2927 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2928 if (!data)
2929 goto login_task_data_alloc_fail;
2930 conn->login_task->data = conn->data = data;
2931
2932 timer_setup(&conn->tmf_timer, iscsi_tmf_timedout, 0);
2933 init_waitqueue_head(&conn->ehwait);
2934
2935 return cls_conn;
2936
2937 login_task_data_alloc_fail:
2938 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2939 sizeof(void*));
2940 login_task_alloc_fail:
2941 iscsi_destroy_conn(cls_conn);
2942 return NULL;
2943 }
2944 EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2945
2946 /**
2947 * iscsi_conn_teardown - teardown iscsi connection
2948 * @cls_conn: iscsi class connection
2949 *
2950 * TODO: we may need to make this into a two step process
2951 * like scsi-mls remove + put host
2952 */
2953 void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2954 {
2955 struct iscsi_conn *conn = cls_conn->dd_data;
2956 struct iscsi_session *session = conn->session;
2957
2958 del_timer_sync(&conn->transport_timer);
2959
2960 mutex_lock(&session->eh_mutex);
2961 spin_lock_bh(&session->frwd_lock);
2962 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2963 if (session->leadconn == conn) {
2964 /*
2965 * leading connection? then give up on recovery.
2966 */
2967 session->state = ISCSI_STATE_TERMINATE;
2968 wake_up(&conn->ehwait);
2969 }
2970 spin_unlock_bh(&session->frwd_lock);
2971
2972 /* flush queued up work because we free the connection below */
2973 iscsi_suspend_tx(conn);
2974
2975 spin_lock_bh(&session->frwd_lock);
2976 free_pages((unsigned long) conn->data,
2977 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2978 kfree(conn->persistent_address);
2979 kfree(conn->local_ipaddr);
2980 /* regular RX path uses back_lock */
2981 spin_lock_bh(&session->back_lock);
2982 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2983 sizeof(void*));
2984 spin_unlock_bh(&session->back_lock);
2985 if (session->leadconn == conn)
2986 session->leadconn = NULL;
2987 spin_unlock_bh(&session->frwd_lock);
2988 mutex_unlock(&session->eh_mutex);
2989
2990 iscsi_destroy_conn(cls_conn);
2991 }
2992 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
2993
2994 int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
2995 {
2996 struct iscsi_conn *conn = cls_conn->dd_data;
2997 struct iscsi_session *session = conn->session;
2998
2999 if (!session) {
3000 iscsi_conn_printk(KERN_ERR, conn,
3001 "can't start unbound connection\n");
3002 return -EPERM;
3003 }
3004
3005 if ((session->imm_data_en || !session->initial_r2t_en) &&
3006 session->first_burst > session->max_burst) {
3007 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
3008 "first_burst %d max_burst %d\n",
3009 session->first_burst, session->max_burst);
3010 return -EINVAL;
3011 }
3012
3013 if (conn->ping_timeout && !conn->recv_timeout) {
3014 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
3015 "zero. Using 5 seconds\n.");
3016 conn->recv_timeout = 5;
3017 }
3018
3019 if (conn->recv_timeout && !conn->ping_timeout) {
3020 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
3021 "zero. Using 5 seconds.\n");
3022 conn->ping_timeout = 5;
3023 }
3024
3025 spin_lock_bh(&session->frwd_lock);
3026 conn->c_stage = ISCSI_CONN_STARTED;
3027 session->state = ISCSI_STATE_LOGGED_IN;
3028 session->queued_cmdsn = session->cmdsn;
3029
3030 conn->last_recv = jiffies;
3031 conn->last_ping = jiffies;
3032 if (conn->recv_timeout && conn->ping_timeout)
3033 mod_timer(&conn->transport_timer,
3034 jiffies + (conn->recv_timeout * HZ));
3035
3036 switch(conn->stop_stage) {
3037 case STOP_CONN_RECOVER:
3038 /*
3039 * unblock eh_abort() if it is blocked. re-try all
3040 * commands after successful recovery
3041 */
3042 conn->stop_stage = 0;
3043 conn->tmf_state = TMF_INITIAL;
3044 session->age++;
3045 if (session->age == 16)
3046 session->age = 0;
3047 break;
3048 case STOP_CONN_TERM:
3049 conn->stop_stage = 0;
3050 break;
3051 default:
3052 break;
3053 }
3054 spin_unlock_bh(&session->frwd_lock);
3055
3056 iscsi_unblock_session(session->cls_session);
3057 wake_up(&conn->ehwait);
3058 return 0;
3059 }
3060 EXPORT_SYMBOL_GPL(iscsi_conn_start);
3061
3062 static void
3063 fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3064 {
3065 struct iscsi_task *task;
3066 int i, state;
3067
3068 for (i = 0; i < conn->session->cmds_max; i++) {
3069 task = conn->session->cmds[i];
3070 if (task->sc)
3071 continue;
3072
3073 if (task->state == ISCSI_TASK_FREE)
3074 continue;
3075
3076 ISCSI_DBG_SESSION(conn->session,
3077 "failing mgmt itt 0x%x state %d\n",
3078 task->itt, task->state);
3079 state = ISCSI_TASK_ABRT_SESS_RECOV;
3080 if (task->state == ISCSI_TASK_PENDING)
3081 state = ISCSI_TASK_COMPLETED;
3082 spin_lock_bh(&session->back_lock);
3083 iscsi_complete_task(task, state);
3084 spin_unlock_bh(&session->back_lock);
3085 }
3086 }
3087
3088 static void iscsi_start_session_recovery(struct iscsi_session *session,
3089 struct iscsi_conn *conn, int flag)
3090 {
3091 int old_stop_stage;
3092
3093 mutex_lock(&session->eh_mutex);
3094 spin_lock_bh(&session->frwd_lock);
3095 if (conn->stop_stage == STOP_CONN_TERM) {
3096 spin_unlock_bh(&session->frwd_lock);
3097 mutex_unlock(&session->eh_mutex);
3098 return;
3099 }
3100
3101 /*
3102 * When this is called for the in_login state, we only want to clean
3103 * up the login task and connection. We do not need to block and set
3104 * the recovery state again
3105 */
3106 if (flag == STOP_CONN_TERM)
3107 session->state = ISCSI_STATE_TERMINATE;
3108 else if (conn->stop_stage != STOP_CONN_RECOVER)
3109 session->state = ISCSI_STATE_IN_RECOVERY;
3110
3111 old_stop_stage = conn->stop_stage;
3112 conn->stop_stage = flag;
3113 spin_unlock_bh(&session->frwd_lock);
3114
3115 del_timer_sync(&conn->transport_timer);
3116 iscsi_suspend_tx(conn);
3117
3118 spin_lock_bh(&session->frwd_lock);
3119 conn->c_stage = ISCSI_CONN_STOPPED;
3120 spin_unlock_bh(&session->frwd_lock);
3121
3122 /*
3123 * for connection level recovery we should not calculate
3124 * header digest. conn->hdr_size used for optimization
3125 * in hdr_extract() and will be re-negotiated at
3126 * set_param() time.
3127 */
3128 if (flag == STOP_CONN_RECOVER) {
3129 conn->hdrdgst_en = 0;
3130 conn->datadgst_en = 0;
3131 if (session->state == ISCSI_STATE_IN_RECOVERY &&
3132 old_stop_stage != STOP_CONN_RECOVER) {
3133 ISCSI_DBG_SESSION(session, "blocking session\n");
3134 iscsi_block_session(session->cls_session);
3135 }
3136 }
3137
3138 /*
3139 * flush queues.
3140 */
3141 spin_lock_bh(&session->frwd_lock);
3142 fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3143 fail_mgmt_tasks(session, conn);
3144 memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
3145 spin_unlock_bh(&session->frwd_lock);
3146 mutex_unlock(&session->eh_mutex);
3147 }
3148
3149 void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3150 {
3151 struct iscsi_conn *conn = cls_conn->dd_data;
3152 struct iscsi_session *session = conn->session;
3153
3154 switch (flag) {
3155 case STOP_CONN_RECOVER:
3156 cls_conn->state = ISCSI_CONN_FAILED;
3157 break;
3158 case STOP_CONN_TERM:
3159 cls_conn->state = ISCSI_CONN_DOWN;
3160 break;
3161 default:
3162 iscsi_conn_printk(KERN_ERR, conn,
3163 "invalid stop flag %d\n", flag);
3164 return;
3165 }
3166
3167 iscsi_start_session_recovery(session, conn, flag);
3168 }
3169 EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3170
3171 int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3172 struct iscsi_cls_conn *cls_conn, int is_leading)
3173 {
3174 struct iscsi_session *session = cls_session->dd_data;
3175 struct iscsi_conn *conn = cls_conn->dd_data;
3176
3177 spin_lock_bh(&session->frwd_lock);
3178 if (is_leading)
3179 session->leadconn = conn;
3180 spin_unlock_bh(&session->frwd_lock);
3181
3182 /*
3183 * Unblock xmitworker(), Login Phase will pass through.
3184 */
3185 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3186 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3187 return 0;
3188 }
3189 EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3190
3191 int iscsi_switch_str_param(char **param, char *new_val_buf)
3192 {
3193 char *new_val;
3194
3195 if (*param) {
3196 if (!strcmp(*param, new_val_buf))
3197 return 0;
3198 }
3199
3200 new_val = kstrdup(new_val_buf, GFP_NOIO);
3201 if (!new_val)
3202 return -ENOMEM;
3203
3204 kfree(*param);
3205 *param = new_val;
3206 return 0;
3207 }
3208 EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3209
3210 int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3211 enum iscsi_param param, char *buf, int buflen)
3212 {
3213 struct iscsi_conn *conn = cls_conn->dd_data;
3214 struct iscsi_session *session = conn->session;
3215 int val;
3216
3217 switch(param) {
3218 case ISCSI_PARAM_FAST_ABORT:
3219 sscanf(buf, "%d", &session->fast_abort);
3220 break;
3221 case ISCSI_PARAM_ABORT_TMO:
3222 sscanf(buf, "%d", &session->abort_timeout);
3223 break;
3224 case ISCSI_PARAM_LU_RESET_TMO:
3225 sscanf(buf, "%d", &session->lu_reset_timeout);
3226 break;
3227 case ISCSI_PARAM_TGT_RESET_TMO:
3228 sscanf(buf, "%d", &session->tgt_reset_timeout);
3229 break;
3230 case ISCSI_PARAM_PING_TMO:
3231 sscanf(buf, "%d", &conn->ping_timeout);
3232 break;
3233 case ISCSI_PARAM_RECV_TMO:
3234 sscanf(buf, "%d", &conn->recv_timeout);
3235 break;
3236 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3237 sscanf(buf, "%d", &conn->max_recv_dlength);
3238 break;
3239 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3240 sscanf(buf, "%d", &conn->max_xmit_dlength);
3241 break;
3242 case ISCSI_PARAM_HDRDGST_EN:
3243 sscanf(buf, "%d", &conn->hdrdgst_en);
3244 break;
3245 case ISCSI_PARAM_DATADGST_EN:
3246 sscanf(buf, "%d", &conn->datadgst_en);
3247 break;
3248 case ISCSI_PARAM_INITIAL_R2T_EN:
3249 sscanf(buf, "%d", &session->initial_r2t_en);
3250 break;
3251 case ISCSI_PARAM_MAX_R2T:
3252 sscanf(buf, "%hu", &session->max_r2t);
3253 break;
3254 case ISCSI_PARAM_IMM_DATA_EN:
3255 sscanf(buf, "%d", &session->imm_data_en);
3256 break;
3257 case ISCSI_PARAM_FIRST_BURST:
3258 sscanf(buf, "%d", &session->first_burst);
3259 break;
3260 case ISCSI_PARAM_MAX_BURST:
3261 sscanf(buf, "%d", &session->max_burst);
3262 break;
3263 case ISCSI_PARAM_PDU_INORDER_EN:
3264 sscanf(buf, "%d", &session->pdu_inorder_en);
3265 break;
3266 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3267 sscanf(buf, "%d", &session->dataseq_inorder_en);
3268 break;
3269 case ISCSI_PARAM_ERL:
3270 sscanf(buf, "%d", &session->erl);
3271 break;
3272 case ISCSI_PARAM_EXP_STATSN:
3273 sscanf(buf, "%u", &conn->exp_statsn);
3274 break;
3275 case ISCSI_PARAM_USERNAME:
3276 return iscsi_switch_str_param(&session->username, buf);
3277 case ISCSI_PARAM_USERNAME_IN:
3278 return iscsi_switch_str_param(&session->username_in, buf);
3279 case ISCSI_PARAM_PASSWORD:
3280 return iscsi_switch_str_param(&session->password, buf);
3281 case ISCSI_PARAM_PASSWORD_IN:
3282 return iscsi_switch_str_param(&session->password_in, buf);
3283 case ISCSI_PARAM_TARGET_NAME:
3284 return iscsi_switch_str_param(&session->targetname, buf);
3285 case ISCSI_PARAM_TARGET_ALIAS:
3286 return iscsi_switch_str_param(&session->targetalias, buf);
3287 case ISCSI_PARAM_TPGT:
3288 sscanf(buf, "%d", &session->tpgt);
3289 break;
3290 case ISCSI_PARAM_PERSISTENT_PORT:
3291 sscanf(buf, "%d", &conn->persistent_port);
3292 break;
3293 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3294 return iscsi_switch_str_param(&conn->persistent_address, buf);
3295 case ISCSI_PARAM_IFACE_NAME:
3296 return iscsi_switch_str_param(&session->ifacename, buf);
3297 case ISCSI_PARAM_INITIATOR_NAME:
3298 return iscsi_switch_str_param(&session->initiatorname, buf);
3299 case ISCSI_PARAM_BOOT_ROOT:
3300 return iscsi_switch_str_param(&session->boot_root, buf);
3301 case ISCSI_PARAM_BOOT_NIC:
3302 return iscsi_switch_str_param(&session->boot_nic, buf);
3303 case ISCSI_PARAM_BOOT_TARGET:
3304 return iscsi_switch_str_param(&session->boot_target, buf);
3305 case ISCSI_PARAM_PORTAL_TYPE:
3306 return iscsi_switch_str_param(&session->portal_type, buf);
3307 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3308 return iscsi_switch_str_param(&session->discovery_parent_type,
3309 buf);
3310 case ISCSI_PARAM_DISCOVERY_SESS:
3311 sscanf(buf, "%d", &val);
3312 session->discovery_sess = !!val;
3313 break;
3314 case ISCSI_PARAM_LOCAL_IPADDR:
3315 return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3316 default:
3317 return -ENOSYS;
3318 }
3319
3320 return 0;
3321 }
3322 EXPORT_SYMBOL_GPL(iscsi_set_param);
3323
3324 int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3325 enum iscsi_param param, char *buf)
3326 {
3327 struct iscsi_session *session = cls_session->dd_data;
3328 int len;
3329
3330 switch(param) {
3331 case ISCSI_PARAM_FAST_ABORT:
3332 len = sprintf(buf, "%d\n", session->fast_abort);
3333 break;
3334 case ISCSI_PARAM_ABORT_TMO:
3335 len = sprintf(buf, "%d\n", session->abort_timeout);
3336 break;
3337 case ISCSI_PARAM_LU_RESET_TMO:
3338 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
3339 break;
3340 case ISCSI_PARAM_TGT_RESET_TMO:
3341 len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
3342 break;
3343 case ISCSI_PARAM_INITIAL_R2T_EN:
3344 len = sprintf(buf, "%d\n", session->initial_r2t_en);
3345 break;
3346 case ISCSI_PARAM_MAX_R2T:
3347 len = sprintf(buf, "%hu\n", session->max_r2t);
3348 break;
3349 case ISCSI_PARAM_IMM_DATA_EN:
3350 len = sprintf(buf, "%d\n", session->imm_data_en);
3351 break;
3352 case ISCSI_PARAM_FIRST_BURST:
3353 len = sprintf(buf, "%u\n", session->first_burst);
3354 break;
3355 case ISCSI_PARAM_MAX_BURST:
3356 len = sprintf(buf, "%u\n", session->max_burst);
3357 break;
3358 case ISCSI_PARAM_PDU_INORDER_EN:
3359 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
3360 break;
3361 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3362 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
3363 break;
3364 case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3365 len = sprintf(buf, "%d\n", session->def_taskmgmt_tmo);
3366 break;
3367 case ISCSI_PARAM_ERL:
3368 len = sprintf(buf, "%d\n", session->erl);
3369 break;
3370 case ISCSI_PARAM_TARGET_NAME:
3371 len = sprintf(buf, "%s\n", session->targetname);
3372 break;
3373 case ISCSI_PARAM_TARGET_ALIAS:
3374 len = sprintf(buf, "%s\n", session->targetalias);
3375 break;
3376 case ISCSI_PARAM_TPGT:
3377 len = sprintf(buf, "%d\n", session->tpgt);
3378 break;
3379 case ISCSI_PARAM_USERNAME:
3380 len = sprintf(buf, "%s\n", session->username);
3381 break;
3382 case ISCSI_PARAM_USERNAME_IN:
3383 len = sprintf(buf, "%s\n", session->username_in);
3384 break;
3385 case ISCSI_PARAM_PASSWORD:
3386 len = sprintf(buf, "%s\n", session->password);
3387 break;
3388 case ISCSI_PARAM_PASSWORD_IN:
3389 len = sprintf(buf, "%s\n", session->password_in);
3390 break;
3391 case ISCSI_PARAM_IFACE_NAME:
3392 len = sprintf(buf, "%s\n", session->ifacename);
3393 break;
3394 case ISCSI_PARAM_INITIATOR_NAME:
3395 len = sprintf(buf, "%s\n", session->initiatorname);
3396 break;
3397 case ISCSI_PARAM_BOOT_ROOT:
3398 len = sprintf(buf, "%s\n", session->boot_root);
3399 break;
3400 case ISCSI_PARAM_BOOT_NIC:
3401 len = sprintf(buf, "%s\n", session->boot_nic);
3402 break;
3403 case ISCSI_PARAM_BOOT_TARGET:
3404 len = sprintf(buf, "%s\n", session->boot_target);
3405 break;
3406 case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3407 len = sprintf(buf, "%u\n", session->auto_snd_tgt_disable);
3408 break;
3409 case ISCSI_PARAM_DISCOVERY_SESS:
3410 len = sprintf(buf, "%u\n", session->discovery_sess);
3411 break;
3412 case ISCSI_PARAM_PORTAL_TYPE:
3413 len = sprintf(buf, "%s\n", session->portal_type);
3414 break;
3415 case ISCSI_PARAM_CHAP_AUTH_EN:
3416 len = sprintf(buf, "%u\n", session->chap_auth_en);
3417 break;
3418 case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3419 len = sprintf(buf, "%u\n", session->discovery_logout_en);
3420 break;
3421 case ISCSI_PARAM_BIDI_CHAP_EN:
3422 len = sprintf(buf, "%u\n", session->bidi_chap_en);
3423 break;
3424 case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3425 len = sprintf(buf, "%u\n", session->discovery_auth_optional);
3426 break;
3427 case ISCSI_PARAM_DEF_TIME2WAIT:
3428 len = sprintf(buf, "%d\n", session->time2wait);
3429 break;
3430 case ISCSI_PARAM_DEF_TIME2RETAIN:
3431 len = sprintf(buf, "%d\n", session->time2retain);
3432 break;
3433 case ISCSI_PARAM_TSID:
3434 len = sprintf(buf, "%u\n", session->tsid);
3435 break;
3436 case ISCSI_PARAM_ISID:
3437 len = sprintf(buf, "%02x%02x%02x%02x%02x%02x\n",
3438 session->isid[0], session->isid[1],
3439 session->isid[2], session->isid[3],
3440 session->isid[4], session->isid[5]);
3441 break;
3442 case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3443 len = sprintf(buf, "%u\n", session->discovery_parent_idx);
3444 break;
3445 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3446 if (session->discovery_parent_type)
3447 len = sprintf(buf, "%s\n",
3448 session->discovery_parent_type);
3449 else
3450 len = sprintf(buf, "\n");
3451 break;
3452 default:
3453 return -ENOSYS;
3454 }
3455
3456 return len;
3457 }
3458 EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3459
3460 int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3461 enum iscsi_param param, char *buf)
3462 {
3463 struct sockaddr_in6 *sin6 = NULL;
3464 struct sockaddr_in *sin = NULL;
3465 int len;
3466
3467 switch (addr->ss_family) {
3468 case AF_INET:
3469 sin = (struct sockaddr_in *)addr;
3470 break;
3471 case AF_INET6:
3472 sin6 = (struct sockaddr_in6 *)addr;
3473 break;
3474 default:
3475 return -EINVAL;
3476 }
3477
3478 switch (param) {
3479 case ISCSI_PARAM_CONN_ADDRESS:
3480 case ISCSI_HOST_PARAM_IPADDRESS:
3481 if (sin)
3482 len = sprintf(buf, "%pI4\n", &sin->sin_addr.s_addr);
3483 else
3484 len = sprintf(buf, "%pI6\n", &sin6->sin6_addr);
3485 break;
3486 case ISCSI_PARAM_CONN_PORT:
3487 case ISCSI_PARAM_LOCAL_PORT:
3488 if (sin)
3489 len = sprintf(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3490 else
3491 len = sprintf(buf, "%hu\n",
3492 be16_to_cpu(sin6->sin6_port));
3493 break;
3494 default:
3495 return -EINVAL;
3496 }
3497
3498 return len;
3499 }
3500 EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3501
3502 int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3503 enum iscsi_param param, char *buf)
3504 {
3505 struct iscsi_conn *conn = cls_conn->dd_data;
3506 int len;
3507
3508 switch(param) {
3509 case ISCSI_PARAM_PING_TMO:
3510 len = sprintf(buf, "%u\n", conn->ping_timeout);
3511 break;
3512 case ISCSI_PARAM_RECV_TMO:
3513 len = sprintf(buf, "%u\n", conn->recv_timeout);
3514 break;
3515 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3516 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
3517 break;
3518 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3519 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
3520 break;
3521 case ISCSI_PARAM_HDRDGST_EN:
3522 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
3523 break;
3524 case ISCSI_PARAM_DATADGST_EN:
3525 len = sprintf(buf, "%d\n", conn->datadgst_en);
3526 break;
3527 case ISCSI_PARAM_IFMARKER_EN:
3528 len = sprintf(buf, "%d\n", conn->ifmarker_en);
3529 break;
3530 case ISCSI_PARAM_OFMARKER_EN:
3531 len = sprintf(buf, "%d\n", conn->ofmarker_en);
3532 break;
3533 case ISCSI_PARAM_EXP_STATSN:
3534 len = sprintf(buf, "%u\n", conn->exp_statsn);
3535 break;
3536 case ISCSI_PARAM_PERSISTENT_PORT:
3537 len = sprintf(buf, "%d\n", conn->persistent_port);
3538 break;
3539 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3540 len = sprintf(buf, "%s\n", conn->persistent_address);
3541 break;
3542 case ISCSI_PARAM_STATSN:
3543 len = sprintf(buf, "%u\n", conn->statsn);
3544 break;
3545 case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3546 len = sprintf(buf, "%u\n", conn->max_segment_size);
3547 break;
3548 case ISCSI_PARAM_KEEPALIVE_TMO:
3549 len = sprintf(buf, "%u\n", conn->keepalive_tmo);
3550 break;
3551 case ISCSI_PARAM_LOCAL_PORT:
3552 len = sprintf(buf, "%u\n", conn->local_port);
3553 break;
3554 case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3555 len = sprintf(buf, "%u\n", conn->tcp_timestamp_stat);
3556 break;
3557 case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3558 len = sprintf(buf, "%u\n", conn->tcp_nagle_disable);
3559 break;
3560 case ISCSI_PARAM_TCP_WSF_DISABLE:
3561 len = sprintf(buf, "%u\n", conn->tcp_wsf_disable);
3562 break;
3563 case ISCSI_PARAM_TCP_TIMER_SCALE:
3564 len = sprintf(buf, "%u\n", conn->tcp_timer_scale);
3565 break;
3566 case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3567 len = sprintf(buf, "%u\n", conn->tcp_timestamp_en);
3568 break;
3569 case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3570 len = sprintf(buf, "%u\n", conn->fragment_disable);
3571 break;
3572 case ISCSI_PARAM_IPV4_TOS:
3573 len = sprintf(buf, "%u\n", conn->ipv4_tos);
3574 break;
3575 case ISCSI_PARAM_IPV6_TC:
3576 len = sprintf(buf, "%u\n", conn->ipv6_traffic_class);
3577 break;
3578 case ISCSI_PARAM_IPV6_FLOW_LABEL:
3579 len = sprintf(buf, "%u\n", conn->ipv6_flow_label);
3580 break;
3581 case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3582 len = sprintf(buf, "%u\n", conn->is_fw_assigned_ipv6);
3583 break;
3584 case ISCSI_PARAM_TCP_XMIT_WSF:
3585 len = sprintf(buf, "%u\n", conn->tcp_xmit_wsf);
3586 break;
3587 case ISCSI_PARAM_TCP_RECV_WSF:
3588 len = sprintf(buf, "%u\n", conn->tcp_recv_wsf);
3589 break;
3590 case ISCSI_PARAM_LOCAL_IPADDR:
3591 len = sprintf(buf, "%s\n", conn->local_ipaddr);
3592 break;
3593 default:
3594 return -ENOSYS;
3595 }
3596
3597 return len;
3598 }
3599 EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3600
3601 int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3602 char *buf)
3603 {
3604 struct iscsi_host *ihost = shost_priv(shost);
3605 int len;
3606
3607 switch (param) {
3608 case ISCSI_HOST_PARAM_NETDEV_NAME:
3609 len = sprintf(buf, "%s\n", ihost->netdev);
3610 break;
3611 case ISCSI_HOST_PARAM_HWADDRESS:
3612 len = sprintf(buf, "%s\n", ihost->hwaddress);
3613 break;
3614 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3615 len = sprintf(buf, "%s\n", ihost->initiatorname);
3616 break;
3617 default:
3618 return -ENOSYS;
3619 }
3620
3621 return len;
3622 }
3623 EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3624
3625 int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3626 char *buf, int buflen)
3627 {
3628 struct iscsi_host *ihost = shost_priv(shost);
3629
3630 switch (param) {
3631 case ISCSI_HOST_PARAM_NETDEV_NAME:
3632 return iscsi_switch_str_param(&ihost->netdev, buf);
3633 case ISCSI_HOST_PARAM_HWADDRESS:
3634 return iscsi_switch_str_param(&ihost->hwaddress, buf);
3635 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3636 return iscsi_switch_str_param(&ihost->initiatorname, buf);
3637 default:
3638 return -ENOSYS;
3639 }
3640
3641 return 0;
3642 }
3643 EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3644
3645 MODULE_AUTHOR("Mike Christie");
3646 MODULE_DESCRIPTION("iSCSI library functions");
3647 MODULE_LICENSE("GPL");
Linux with added FPC-III support