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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
32static int iscsi_dbg_lib_conn;
33module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
34 S_IRUGO | S_IWUSR);
35MODULE_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
39static int iscsi_dbg_lib_session;
40module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
41 S_IRUGO | S_IWUSR);
42MODULE_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
46static int iscsi_dbg_lib_eh;
47module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
48 S_IRUGO | S_IWUSR);
49MODULE_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#define ISCSI_CMD_COMPL_WAIT 5
87
88inline void iscsi_conn_queue_xmit(struct iscsi_conn *conn)
89{
90 struct Scsi_Host *shost = conn->session->host;
91 struct iscsi_host *ihost = shost_priv(shost);
92
93 if (ihost->workq)
94 queue_work(ihost->workq, &conn->xmitwork);
95}
96EXPORT_SYMBOL_GPL(iscsi_conn_queue_xmit);
97
98inline void iscsi_conn_queue_recv(struct iscsi_conn *conn)
99{
100 struct Scsi_Host *shost = conn->session->host;
101 struct iscsi_host *ihost = shost_priv(shost);
102
103 if (ihost->workq && !test_bit(ISCSI_CONN_FLAG_SUSPEND_RX, &conn->flags))
104 queue_work(ihost->workq, &conn->recvwork);
105}
106EXPORT_SYMBOL_GPL(iscsi_conn_queue_recv);
107
108static void __iscsi_update_cmdsn(struct iscsi_session *session,
109 uint32_t exp_cmdsn, uint32_t max_cmdsn)
110{
111 /*
112 * standard specifies this check for when to update expected and
113 * max sequence numbers
114 */
115 if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
116 return;
117
118 if (exp_cmdsn != session->exp_cmdsn &&
119 !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
120 session->exp_cmdsn = exp_cmdsn;
121
122 if (max_cmdsn != session->max_cmdsn &&
123 !iscsi_sna_lt(max_cmdsn, session->max_cmdsn))
124 session->max_cmdsn = max_cmdsn;
125}
126
127void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
128{
129 __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
130 be32_to_cpu(hdr->max_cmdsn));
131}
132EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
133
134/**
135 * iscsi_prep_data_out_pdu - initialize Data-Out
136 * @task: scsi command task
137 * @r2t: R2T info
138 * @hdr: iscsi data in pdu
139 *
140 * Notes:
141 * Initialize Data-Out within this R2T sequence and finds
142 * proper data_offset within this SCSI command.
143 *
144 * This function is called with connection lock taken.
145 **/
146void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
147 struct iscsi_data *hdr)
148{
149 struct iscsi_conn *conn = task->conn;
150 unsigned int left = r2t->data_length - r2t->sent;
151
152 task->hdr_len = sizeof(struct iscsi_data);
153
154 memset(hdr, 0, sizeof(struct iscsi_data));
155 hdr->ttt = r2t->ttt;
156 hdr->datasn = cpu_to_be32(r2t->datasn);
157 r2t->datasn++;
158 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
159 hdr->lun = task->lun;
160 hdr->itt = task->hdr_itt;
161 hdr->exp_statsn = r2t->exp_statsn;
162 hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
163 if (left > conn->max_xmit_dlength) {
164 hton24(hdr->dlength, conn->max_xmit_dlength);
165 r2t->data_count = conn->max_xmit_dlength;
166 hdr->flags = 0;
167 } else {
168 hton24(hdr->dlength, left);
169 r2t->data_count = left;
170 hdr->flags = ISCSI_FLAG_CMD_FINAL;
171 }
172 conn->dataout_pdus_cnt++;
173}
174EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
175
176static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
177{
178 unsigned exp_len = task->hdr_len + len;
179
180 if (exp_len > task->hdr_max) {
181 WARN_ON(1);
182 return -EINVAL;
183 }
184
185 WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
186 task->hdr_len = exp_len;
187 return 0;
188}
189
190/*
191 * make an extended cdb AHS
192 */
193static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
194{
195 struct scsi_cmnd *cmd = task->sc;
196 unsigned rlen, pad_len;
197 unsigned short ahslength;
198 struct iscsi_ecdb_ahdr *ecdb_ahdr;
199 int rc;
200
201 ecdb_ahdr = iscsi_next_hdr(task);
202 rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
203
204 BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
205 ahslength = rlen + sizeof(ecdb_ahdr->reserved);
206
207 pad_len = iscsi_padding(rlen);
208
209 rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
210 sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
211 if (rc)
212 return rc;
213
214 if (pad_len)
215 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
216
217 ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
218 ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
219 ecdb_ahdr->reserved = 0;
220 memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
221
222 ISCSI_DBG_SESSION(task->conn->session,
223 "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
224 "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
225 "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
226 task->hdr_len);
227 return 0;
228}
229
230/**
231 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
232 * @task: iscsi task
233 * @opcode: opcode to check for
234 *
235 * During TMF a task has to be checked if it's affected.
236 * All unrelated I/O can be passed through, but I/O to the
237 * affected LUN should be restricted.
238 * If 'fast_abort' is set we won't be sending any I/O to the
239 * affected LUN.
240 * Otherwise the target is waiting for all TTTs to be completed,
241 * so we have to send all outstanding Data-Out PDUs to the target.
242 */
243static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
244{
245 struct iscsi_session *session = task->conn->session;
246 struct iscsi_tm *tmf = &session->tmhdr;
247 u64 hdr_lun;
248
249 if (session->tmf_state == TMF_INITIAL)
250 return 0;
251
252 if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
253 return 0;
254
255 switch (ISCSI_TM_FUNC_VALUE(tmf)) {
256 case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
257 /*
258 * Allow PDUs for unrelated LUNs
259 */
260 hdr_lun = scsilun_to_int(&tmf->lun);
261 if (hdr_lun != task->sc->device->lun)
262 return 0;
263 fallthrough;
264 case ISCSI_TM_FUNC_TARGET_WARM_RESET:
265 /*
266 * Fail all SCSI cmd PDUs
267 */
268 if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
269 iscsi_session_printk(KERN_INFO, session,
270 "task [op %x itt 0x%x/0x%x] rejected.\n",
271 opcode, task->itt, task->hdr_itt);
272 return -EACCES;
273 }
274 /*
275 * And also all data-out PDUs in response to R2T
276 * if fast_abort is set.
277 */
278 if (session->fast_abort) {
279 iscsi_session_printk(KERN_INFO, session,
280 "task [op %x itt 0x%x/0x%x] fast abort.\n",
281 opcode, task->itt, task->hdr_itt);
282 return -EACCES;
283 }
284 break;
285 case ISCSI_TM_FUNC_ABORT_TASK:
286 /*
287 * the caller has already checked if the task
288 * they want to abort was in the pending queue so if
289 * we are here the cmd pdu has gone out already, and
290 * we will only hit this for data-outs
291 */
292 if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
293 task->hdr_itt == tmf->rtt) {
294 ISCSI_DBG_SESSION(session,
295 "Preventing task %x/%x from sending "
296 "data-out due to abort task in "
297 "progress\n", task->itt,
298 task->hdr_itt);
299 return -EACCES;
300 }
301 break;
302 }
303
304 return 0;
305}
306
307/**
308 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
309 * @task: iscsi task
310 *
311 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
312 * fields like dlength or final based on how much data it sends
313 */
314static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
315{
316 struct iscsi_conn *conn = task->conn;
317 struct iscsi_session *session = conn->session;
318 struct scsi_cmnd *sc = task->sc;
319 struct iscsi_scsi_req *hdr;
320 unsigned hdrlength, cmd_len, transfer_length;
321 itt_t itt;
322 int rc;
323
324 rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
325 if (rc)
326 return rc;
327
328 if (conn->session->tt->alloc_pdu) {
329 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
330 if (rc)
331 return rc;
332 }
333 hdr = (struct iscsi_scsi_req *)task->hdr;
334 itt = hdr->itt;
335 memset(hdr, 0, sizeof(*hdr));
336
337 if (session->tt->parse_pdu_itt)
338 hdr->itt = task->hdr_itt = itt;
339 else
340 hdr->itt = task->hdr_itt = build_itt(task->itt,
341 task->conn->session->age);
342 task->hdr_len = 0;
343 rc = iscsi_add_hdr(task, sizeof(*hdr));
344 if (rc)
345 return rc;
346 hdr->opcode = ISCSI_OP_SCSI_CMD;
347 hdr->flags = ISCSI_ATTR_SIMPLE;
348 int_to_scsilun(sc->device->lun, &hdr->lun);
349 task->lun = hdr->lun;
350 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
351 cmd_len = sc->cmd_len;
352 if (cmd_len < ISCSI_CDB_SIZE)
353 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
354 else if (cmd_len > ISCSI_CDB_SIZE) {
355 rc = iscsi_prep_ecdb_ahs(task);
356 if (rc)
357 return rc;
358 cmd_len = ISCSI_CDB_SIZE;
359 }
360 memcpy(hdr->cdb, sc->cmnd, cmd_len);
361
362 task->imm_count = 0;
363 if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL)
364 task->protected = true;
365
366 transfer_length = scsi_transfer_length(sc);
367 hdr->data_length = cpu_to_be32(transfer_length);
368 if (sc->sc_data_direction == DMA_TO_DEVICE) {
369 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
370
371 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
372 /*
373 * Write counters:
374 *
375 * imm_count bytes to be sent right after
376 * SCSI PDU Header
377 *
378 * unsol_count bytes(as Data-Out) to be sent
379 * without R2T ack right after
380 * immediate data
381 *
382 * r2t data_length bytes to be sent via R2T ack's
383 *
384 * pad_count bytes to be sent as zero-padding
385 */
386 memset(r2t, 0, sizeof(*r2t));
387
388 if (session->imm_data_en) {
389 if (transfer_length >= session->first_burst)
390 task->imm_count = min(session->first_burst,
391 conn->max_xmit_dlength);
392 else
393 task->imm_count = min(transfer_length,
394 conn->max_xmit_dlength);
395 hton24(hdr->dlength, task->imm_count);
396 } else
397 zero_data(hdr->dlength);
398
399 if (!session->initial_r2t_en) {
400 r2t->data_length = min(session->first_burst,
401 transfer_length) -
402 task->imm_count;
403 r2t->data_offset = task->imm_count;
404 r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
405 r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
406 }
407
408 if (!task->unsol_r2t.data_length)
409 /* No unsolicit Data-Out's */
410 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
411 } else {
412 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
413 zero_data(hdr->dlength);
414
415 if (sc->sc_data_direction == DMA_FROM_DEVICE)
416 hdr->flags |= ISCSI_FLAG_CMD_READ;
417 }
418
419 /* calculate size of additional header segments (AHSs) */
420 hdrlength = task->hdr_len - sizeof(*hdr);
421
422 WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
423 hdrlength /= ISCSI_PAD_LEN;
424
425 WARN_ON(hdrlength >= 256);
426 hdr->hlength = hdrlength & 0xFF;
427 hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
428
429 if (session->tt->init_task && session->tt->init_task(task))
430 return -EIO;
431
432 task->state = ISCSI_TASK_RUNNING;
433 session->cmdsn++;
434
435 conn->scsicmd_pdus_cnt++;
436 ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
437 "itt 0x%x len %d cmdsn %d win %d]\n",
438 sc->sc_data_direction == DMA_TO_DEVICE ?
439 "write" : "read", conn->id, sc, sc->cmnd[0],
440 task->itt, transfer_length,
441 session->cmdsn,
442 session->max_cmdsn - session->exp_cmdsn + 1);
443 return 0;
444}
445
446/**
447 * iscsi_free_task - free a task
448 * @task: iscsi cmd task
449 *
450 * Must be called with session back_lock.
451 * This function returns the scsi command to scsi-ml or cleans
452 * up mgmt tasks then returns the task to the pool.
453 */
454static void iscsi_free_task(struct iscsi_task *task)
455{
456 struct iscsi_conn *conn = task->conn;
457 struct iscsi_session *session = conn->session;
458 struct scsi_cmnd *sc = task->sc;
459 int oldstate = task->state;
460
461 ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
462 task->itt, task->state, task->sc);
463
464 session->tt->cleanup_task(task);
465 task->state = ISCSI_TASK_FREE;
466 task->sc = NULL;
467 /*
468 * login task is preallocated so do not free
469 */
470 if (conn->login_task == task)
471 return;
472
473 kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
474
475 if (sc) {
476 /* SCSI eh reuses commands to verify us */
477 iscsi_cmd(sc)->task = NULL;
478 /*
479 * queue command may call this to free the task, so
480 * it will decide how to return sc to scsi-ml.
481 */
482 if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
483 scsi_done(sc);
484 }
485}
486
487bool iscsi_get_task(struct iscsi_task *task)
488{
489 return refcount_inc_not_zero(&task->refcount);
490}
491EXPORT_SYMBOL_GPL(iscsi_get_task);
492
493/**
494 * __iscsi_put_task - drop the refcount on a task
495 * @task: iscsi_task to drop the refcount on
496 *
497 * The back_lock must be held when calling in case it frees the task.
498 */
499void __iscsi_put_task(struct iscsi_task *task)
500{
501 if (refcount_dec_and_test(&task->refcount))
502 iscsi_free_task(task);
503}
504EXPORT_SYMBOL_GPL(__iscsi_put_task);
505
506void iscsi_put_task(struct iscsi_task *task)
507{
508 struct iscsi_session *session = task->conn->session;
509
510 if (refcount_dec_and_test(&task->refcount)) {
511 spin_lock_bh(&session->back_lock);
512 iscsi_free_task(task);
513 spin_unlock_bh(&session->back_lock);
514 }
515}
516EXPORT_SYMBOL_GPL(iscsi_put_task);
517
518/**
519 * iscsi_complete_task - finish a task
520 * @task: iscsi cmd task
521 * @state: state to complete task with
522 *
523 * Must be called with session back_lock.
524 */
525static void iscsi_complete_task(struct iscsi_task *task, int state)
526{
527 struct iscsi_conn *conn = task->conn;
528
529 ISCSI_DBG_SESSION(conn->session,
530 "complete task itt 0x%x state %d sc %p\n",
531 task->itt, task->state, task->sc);
532 if (task->state == ISCSI_TASK_COMPLETED ||
533 task->state == ISCSI_TASK_ABRT_TMF ||
534 task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
535 task->state == ISCSI_TASK_REQUEUE_SCSIQ)
536 return;
537 WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
538 task->state = state;
539
540 if (READ_ONCE(conn->ping_task) == task)
541 WRITE_ONCE(conn->ping_task, NULL);
542
543 /* release get from queueing */
544 __iscsi_put_task(task);
545}
546
547/**
548 * iscsi_complete_scsi_task - finish scsi task normally
549 * @task: iscsi task for scsi cmd
550 * @exp_cmdsn: expected cmd sn in cpu format
551 * @max_cmdsn: max cmd sn in cpu format
552 *
553 * This is used when drivers do not need or cannot perform
554 * lower level pdu processing.
555 *
556 * Called with session back_lock
557 */
558void iscsi_complete_scsi_task(struct iscsi_task *task,
559 uint32_t exp_cmdsn, uint32_t max_cmdsn)
560{
561 struct iscsi_conn *conn = task->conn;
562
563 ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
564
565 conn->last_recv = jiffies;
566 __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
567 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
568}
569EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
570
571/*
572 * Must be called with back and frwd lock
573 */
574static bool cleanup_queued_task(struct iscsi_task *task)
575{
576 struct iscsi_conn *conn = task->conn;
577 bool early_complete = false;
578
579 /*
580 * We might have raced where we handled a R2T early and got a response
581 * but have not yet taken the task off the requeue list, then a TMF or
582 * recovery happened and so we can still see it here.
583 */
584 if (task->state == ISCSI_TASK_COMPLETED)
585 early_complete = true;
586
587 if (!list_empty(&task->running)) {
588 list_del_init(&task->running);
589 /*
590 * If it's on a list but still running this could be cleanup
591 * from a TMF or session recovery.
592 */
593 if (task->state == ISCSI_TASK_RUNNING ||
594 task->state == ISCSI_TASK_COMPLETED)
595 __iscsi_put_task(task);
596 }
597
598 if (conn->session->running_aborted_task == task) {
599 conn->session->running_aborted_task = NULL;
600 __iscsi_put_task(task);
601 }
602
603 if (conn->task == task) {
604 conn->task = NULL;
605 __iscsi_put_task(task);
606 }
607
608 return early_complete;
609}
610
611/*
612 * session back and frwd lock must be held and if not called for a task that
613 * is still pending or from the xmit thread, then xmit thread must be suspended
614 */
615static void __fail_scsi_task(struct iscsi_task *task, int err)
616{
617 struct iscsi_conn *conn = task->conn;
618 struct scsi_cmnd *sc;
619 int state;
620
621 if (cleanup_queued_task(task))
622 return;
623
624 if (task->state == ISCSI_TASK_PENDING) {
625 /*
626 * cmd never made it to the xmit thread, so we should not count
627 * the cmd in the sequencing
628 */
629 conn->session->queued_cmdsn--;
630 /* it was never sent so just complete like normal */
631 state = ISCSI_TASK_COMPLETED;
632 } else if (err == DID_TRANSPORT_DISRUPTED)
633 state = ISCSI_TASK_ABRT_SESS_RECOV;
634 else
635 state = ISCSI_TASK_ABRT_TMF;
636
637 sc = task->sc;
638 sc->result = err << 16;
639 scsi_set_resid(sc, scsi_bufflen(sc));
640 iscsi_complete_task(task, state);
641}
642
643static void fail_scsi_task(struct iscsi_task *task, int err)
644{
645 struct iscsi_session *session = task->conn->session;
646
647 spin_lock_bh(&session->back_lock);
648 __fail_scsi_task(task, err);
649 spin_unlock_bh(&session->back_lock);
650}
651
652static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
653 struct iscsi_task *task)
654{
655 struct iscsi_session *session = conn->session;
656 struct iscsi_hdr *hdr = task->hdr;
657 struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
658 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
659
660 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
661 return -ENOTCONN;
662
663 if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
664 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
665 /*
666 * pre-format CmdSN for outgoing PDU.
667 */
668 nop->cmdsn = cpu_to_be32(session->cmdsn);
669 if (hdr->itt != RESERVED_ITT) {
670 /*
671 * TODO: We always use immediate for normal session pdus.
672 * If we start to send tmfs or nops as non-immediate then
673 * we should start checking the cmdsn numbers for mgmt tasks.
674 *
675 * During discovery sessions iscsid sends TEXT as non immediate,
676 * but we always only send one PDU at a time.
677 */
678 if (conn->c_stage == ISCSI_CONN_STARTED &&
679 !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
680 session->queued_cmdsn++;
681 session->cmdsn++;
682 }
683 }
684
685 if (session->tt->init_task && session->tt->init_task(task))
686 return -EIO;
687
688 if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
689 session->state = ISCSI_STATE_LOGGING_OUT;
690
691 task->state = ISCSI_TASK_RUNNING;
692 ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
693 "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
694 hdr->itt, task->data_count);
695 return 0;
696}
697
698/**
699 * iscsi_alloc_mgmt_task - allocate and setup a mgmt task.
700 * @conn: iscsi conn that the task will be sent on.
701 * @hdr: iscsi pdu that will be sent.
702 * @data: buffer for data segment if needed.
703 * @data_size: length of data in bytes.
704 */
705static struct iscsi_task *
706iscsi_alloc_mgmt_task(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
707 char *data, uint32_t data_size)
708{
709 struct iscsi_session *session = conn->session;
710 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
711 struct iscsi_task *task;
712 itt_t itt;
713
714 if (session->state == ISCSI_STATE_TERMINATE ||
715 !test_bit(ISCSI_CONN_FLAG_BOUND, &conn->flags))
716 return NULL;
717
718 if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
719 /*
720 * Login and Text are sent serially, in
721 * request-followed-by-response sequence.
722 * Same task can be used. Same ITT must be used.
723 * Note that login_task is preallocated at conn_create().
724 */
725 if (conn->login_task->state != ISCSI_TASK_FREE) {
726 iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
727 "progress. Cannot start new task.\n");
728 return NULL;
729 }
730
731 if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
732 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);
733 return NULL;
734 }
735
736 task = conn->login_task;
737 } else {
738 if (session->state != ISCSI_STATE_LOGGED_IN)
739 return NULL;
740
741 if (data_size != 0) {
742 iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
743 return NULL;
744 }
745
746 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
747 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
748
749 if (!kfifo_out(&session->cmdpool.queue,
750 (void*)&task, sizeof(void*)))
751 return NULL;
752 }
753 /*
754 * released in complete pdu for task we expect a response for, and
755 * released by the lld when it has transmitted the task for
756 * pdus we do not expect a response for.
757 */
758 refcount_set(&task->refcount, 1);
759 task->conn = conn;
760 task->sc = NULL;
761 INIT_LIST_HEAD(&task->running);
762 task->state = ISCSI_TASK_PENDING;
763
764 if (data_size) {
765 memcpy(task->data, data, data_size);
766 task->data_count = data_size;
767 } else
768 task->data_count = 0;
769
770 if (conn->session->tt->alloc_pdu) {
771 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
772 iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
773 "pdu for mgmt task.\n");
774 goto free_task;
775 }
776 }
777
778 itt = task->hdr->itt;
779 task->hdr_len = sizeof(struct iscsi_hdr);
780 memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
781
782 if (hdr->itt != RESERVED_ITT) {
783 if (session->tt->parse_pdu_itt)
784 task->hdr->itt = itt;
785 else
786 task->hdr->itt = build_itt(task->itt,
787 task->conn->session->age);
788 }
789
790 return task;
791
792free_task:
793 iscsi_put_task(task);
794 return NULL;
795}
796
797/**
798 * iscsi_send_mgmt_task - Send task created with iscsi_alloc_mgmt_task.
799 * @task: iscsi task to send.
800 *
801 * On failure this returns a non-zero error code, and the driver must free
802 * the task with iscsi_put_task;
803 */
804static int iscsi_send_mgmt_task(struct iscsi_task *task)
805{
806 struct iscsi_conn *conn = task->conn;
807 struct iscsi_session *session = conn->session;
808 struct iscsi_host *ihost = shost_priv(conn->session->host);
809 int rc = 0;
810
811 if (!ihost->workq) {
812 rc = iscsi_prep_mgmt_task(conn, task);
813 if (rc)
814 return rc;
815
816 rc = session->tt->xmit_task(task);
817 if (rc)
818 return rc;
819 } else {
820 list_add_tail(&task->running, &conn->mgmtqueue);
821 iscsi_conn_queue_xmit(conn);
822 }
823
824 return 0;
825}
826
827static int __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
828 char *data, uint32_t data_size)
829{
830 struct iscsi_task *task;
831 int rc;
832
833 task = iscsi_alloc_mgmt_task(conn, hdr, data, data_size);
834 if (!task)
835 return -ENOMEM;
836
837 rc = iscsi_send_mgmt_task(task);
838 if (rc)
839 iscsi_put_task(task);
840 return rc;
841}
842
843int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
844 char *data, uint32_t data_size)
845{
846 struct iscsi_conn *conn = cls_conn->dd_data;
847 struct iscsi_session *session = conn->session;
848 int err = 0;
849
850 spin_lock_bh(&session->frwd_lock);
851 if (__iscsi_conn_send_pdu(conn, hdr, data, data_size))
852 err = -EPERM;
853 spin_unlock_bh(&session->frwd_lock);
854 return err;
855}
856EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
857
858/**
859 * iscsi_scsi_cmd_rsp - SCSI Command Response processing
860 * @conn: iscsi connection
861 * @hdr: iscsi header
862 * @task: scsi command task
863 * @data: cmd data buffer
864 * @datalen: len of buffer
865 *
866 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
867 * then completes the command and task. called under back_lock
868 **/
869static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
870 struct iscsi_task *task, char *data,
871 int datalen)
872{
873 struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
874 struct iscsi_session *session = conn->session;
875 struct scsi_cmnd *sc = task->sc;
876
877 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
878 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
879
880 sc->result = (DID_OK << 16) | rhdr->cmd_status;
881
882 if (task->protected) {
883 sector_t sector;
884 u8 ascq;
885
886 /**
887 * Transports that didn't implement check_protection
888 * callback but still published T10-PI support to scsi-mid
889 * deserve this BUG_ON.
890 **/
891 BUG_ON(!session->tt->check_protection);
892
893 ascq = session->tt->check_protection(task, §or);
894 if (ascq) {
895 scsi_build_sense(sc, 1, ILLEGAL_REQUEST, 0x10, ascq);
896 scsi_set_sense_information(sc->sense_buffer,
897 SCSI_SENSE_BUFFERSIZE,
898 sector);
899 goto out;
900 }
901 }
902
903 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
904 sc->result = DID_ERROR << 16;
905 goto out;
906 }
907
908 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
909 uint16_t senselen;
910
911 if (datalen < 2) {
912invalid_datalen:
913 iscsi_conn_printk(KERN_ERR, conn,
914 "Got CHECK_CONDITION but invalid data "
915 "buffer size of %d\n", datalen);
916 sc->result = DID_BAD_TARGET << 16;
917 goto out;
918 }
919
920 senselen = get_unaligned_be16(data);
921 if (datalen < senselen)
922 goto invalid_datalen;
923
924 memcpy(sc->sense_buffer, data + 2,
925 min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
926 ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
927 min_t(uint16_t, senselen,
928 SCSI_SENSE_BUFFERSIZE));
929 }
930
931 if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
932 ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
933 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
934 }
935
936 if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
937 ISCSI_FLAG_CMD_OVERFLOW)) {
938 int res_count = be32_to_cpu(rhdr->residual_count);
939
940 if (res_count > 0 &&
941 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
942 res_count <= scsi_bufflen(sc)))
943 /* write side for bidi or uni-io set_resid */
944 scsi_set_resid(sc, res_count);
945 else
946 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
947 }
948out:
949 ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
950 sc, sc->result, task->itt);
951 conn->scsirsp_pdus_cnt++;
952 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
953}
954
955/**
956 * iscsi_data_in_rsp - SCSI Data-In Response processing
957 * @conn: iscsi connection
958 * @hdr: iscsi pdu
959 * @task: scsi command task
960 *
961 * iscsi_data_in_rsp sets up the scsi_cmnd fields based on the data received
962 * then completes the command and task. called under back_lock
963 **/
964static void
965iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
966 struct iscsi_task *task)
967{
968 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
969 struct scsi_cmnd *sc = task->sc;
970
971 if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
972 return;
973
974 iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
975 sc->result = (DID_OK << 16) | rhdr->cmd_status;
976 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
977 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
978 ISCSI_FLAG_DATA_OVERFLOW)) {
979 int res_count = be32_to_cpu(rhdr->residual_count);
980
981 if (res_count > 0 &&
982 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
983 res_count <= sc->sdb.length))
984 scsi_set_resid(sc, res_count);
985 else
986 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
987 }
988
989 ISCSI_DBG_SESSION(conn->session, "data in with status done "
990 "[sc %p res %d itt 0x%x]\n",
991 sc, sc->result, task->itt);
992 conn->scsirsp_pdus_cnt++;
993 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
994}
995
996static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
997{
998 struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
999 struct iscsi_session *session = conn->session;
1000
1001 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1002 conn->tmfrsp_pdus_cnt++;
1003
1004 if (session->tmf_state != TMF_QUEUED)
1005 return;
1006
1007 if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
1008 session->tmf_state = TMF_SUCCESS;
1009 else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
1010 session->tmf_state = TMF_NOT_FOUND;
1011 else
1012 session->tmf_state = TMF_FAILED;
1013 wake_up(&session->ehwait);
1014}
1015
1016static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
1017{
1018 struct iscsi_nopout hdr;
1019 struct iscsi_task *task;
1020
1021 if (!rhdr) {
1022 if (READ_ONCE(conn->ping_task))
1023 return -EINVAL;
1024 }
1025
1026 memset(&hdr, 0, sizeof(struct iscsi_nopout));
1027 hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
1028 hdr.flags = ISCSI_FLAG_CMD_FINAL;
1029
1030 if (rhdr) {
1031 hdr.lun = rhdr->lun;
1032 hdr.ttt = rhdr->ttt;
1033 hdr.itt = RESERVED_ITT;
1034 } else
1035 hdr.ttt = RESERVED_ITT;
1036
1037 task = iscsi_alloc_mgmt_task(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
1038 if (!task)
1039 return -ENOMEM;
1040
1041 if (!rhdr)
1042 WRITE_ONCE(conn->ping_task, task);
1043
1044 if (iscsi_send_mgmt_task(task)) {
1045 if (!rhdr)
1046 WRITE_ONCE(conn->ping_task, NULL);
1047 iscsi_put_task(task);
1048
1049 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
1050 return -EIO;
1051 } else if (!rhdr) {
1052 /* only track our nops */
1053 conn->last_ping = jiffies;
1054 }
1055
1056 return 0;
1057}
1058
1059/**
1060 * iscsi_nop_out_rsp - SCSI NOP Response processing
1061 * @task: scsi command task
1062 * @nop: the nop structure
1063 * @data: where to put the data
1064 * @datalen: length of data
1065 *
1066 * iscsi_nop_out_rsp handles nop response from use or
1067 * from user space. called under back_lock
1068 **/
1069static int iscsi_nop_out_rsp(struct iscsi_task *task,
1070 struct iscsi_nopin *nop, char *data, int datalen)
1071{
1072 struct iscsi_conn *conn = task->conn;
1073 int rc = 0;
1074
1075 if (READ_ONCE(conn->ping_task) != task) {
1076 /*
1077 * If this is not in response to one of our
1078 * nops then it must be from userspace.
1079 */
1080 if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
1081 data, datalen))
1082 rc = ISCSI_ERR_CONN_FAILED;
1083 } else
1084 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
1085 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1086 return rc;
1087}
1088
1089static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1090 char *data, int datalen)
1091{
1092 struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1093 struct iscsi_hdr rejected_pdu;
1094 int opcode, rc = 0;
1095
1096 conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1097
1098 if (ntoh24(reject->dlength) > datalen ||
1099 ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1100 iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1101 "pdu. Invalid data length (pdu dlength "
1102 "%u, datalen %d\n", ntoh24(reject->dlength),
1103 datalen);
1104 return ISCSI_ERR_PROTO;
1105 }
1106 memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1107 opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1108
1109 switch (reject->reason) {
1110 case ISCSI_REASON_DATA_DIGEST_ERROR:
1111 iscsi_conn_printk(KERN_ERR, conn,
1112 "pdu (op 0x%x itt 0x%x) rejected "
1113 "due to DataDigest error.\n",
1114 opcode, rejected_pdu.itt);
1115 break;
1116 case ISCSI_REASON_IMM_CMD_REJECT:
1117 iscsi_conn_printk(KERN_ERR, conn,
1118 "pdu (op 0x%x itt 0x%x) rejected. Too many "
1119 "immediate commands.\n",
1120 opcode, rejected_pdu.itt);
1121 /*
1122 * We only send one TMF at a time so if the target could not
1123 * handle it, then it should get fixed (RFC mandates that
1124 * a target can handle one immediate TMF per conn).
1125 *
1126 * For nops-outs, we could have sent more than one if
1127 * the target is sending us lots of nop-ins
1128 */
1129 if (opcode != ISCSI_OP_NOOP_OUT)
1130 return 0;
1131
1132 if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1133 /*
1134 * nop-out in response to target's nop-out rejected.
1135 * Just resend.
1136 */
1137 /* In RX path we are under back lock */
1138 spin_unlock(&conn->session->back_lock);
1139 spin_lock(&conn->session->frwd_lock);
1140 iscsi_send_nopout(conn,
1141 (struct iscsi_nopin*)&rejected_pdu);
1142 spin_unlock(&conn->session->frwd_lock);
1143 spin_lock(&conn->session->back_lock);
1144 } else {
1145 struct iscsi_task *task;
1146 /*
1147 * Our nop as ping got dropped. We know the target
1148 * and transport are ok so just clean up
1149 */
1150 task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1151 if (!task) {
1152 iscsi_conn_printk(KERN_ERR, conn,
1153 "Invalid pdu reject. Could "
1154 "not lookup rejected task.\n");
1155 rc = ISCSI_ERR_BAD_ITT;
1156 } else
1157 rc = iscsi_nop_out_rsp(task,
1158 (struct iscsi_nopin*)&rejected_pdu,
1159 NULL, 0);
1160 }
1161 break;
1162 default:
1163 iscsi_conn_printk(KERN_ERR, conn,
1164 "pdu (op 0x%x itt 0x%x) rejected. Reason "
1165 "code 0x%x\n", rejected_pdu.opcode,
1166 rejected_pdu.itt, reject->reason);
1167 break;
1168 }
1169 return rc;
1170}
1171
1172/**
1173 * iscsi_itt_to_task - look up task by itt
1174 * @conn: iscsi connection
1175 * @itt: itt
1176 *
1177 * This should be used for mgmt tasks like login and nops, or if
1178 * the LDD's itt space does not include the session age.
1179 *
1180 * The session back_lock must be held.
1181 */
1182struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1183{
1184 struct iscsi_session *session = conn->session;
1185 int i;
1186
1187 if (itt == RESERVED_ITT)
1188 return NULL;
1189
1190 if (session->tt->parse_pdu_itt)
1191 session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1192 else
1193 i = get_itt(itt);
1194 if (i >= session->cmds_max)
1195 return NULL;
1196
1197 return session->cmds[i];
1198}
1199EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1200
1201/**
1202 * __iscsi_complete_pdu - complete pdu
1203 * @conn: iscsi conn
1204 * @hdr: iscsi header
1205 * @data: data buffer
1206 * @datalen: len of data buffer
1207 *
1208 * Completes pdu processing by freeing any resources allocated at
1209 * queuecommand or send generic. session back_lock must be held and verify
1210 * itt must have been called.
1211 */
1212int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1213 char *data, int datalen)
1214{
1215 struct iscsi_session *session = conn->session;
1216 int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1217 struct iscsi_task *task;
1218 uint32_t itt;
1219
1220 conn->last_recv = jiffies;
1221 rc = iscsi_verify_itt(conn, hdr->itt);
1222 if (rc)
1223 return rc;
1224
1225 if (hdr->itt != RESERVED_ITT)
1226 itt = get_itt(hdr->itt);
1227 else
1228 itt = ~0U;
1229
1230 ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1231 opcode, conn->id, itt, datalen);
1232
1233 if (itt == ~0U) {
1234 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1235
1236 switch(opcode) {
1237 case ISCSI_OP_NOOP_IN:
1238 if (datalen) {
1239 rc = ISCSI_ERR_PROTO;
1240 break;
1241 }
1242
1243 if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1244 break;
1245
1246 /* In RX path we are under back lock */
1247 spin_unlock(&session->back_lock);
1248 spin_lock(&session->frwd_lock);
1249 iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1250 spin_unlock(&session->frwd_lock);
1251 spin_lock(&session->back_lock);
1252 break;
1253 case ISCSI_OP_REJECT:
1254 rc = iscsi_handle_reject(conn, hdr, data, datalen);
1255 break;
1256 case ISCSI_OP_ASYNC_EVENT:
1257 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1258 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1259 rc = ISCSI_ERR_CONN_FAILED;
1260 break;
1261 default:
1262 rc = ISCSI_ERR_BAD_OPCODE;
1263 break;
1264 }
1265 goto out;
1266 }
1267
1268 switch(opcode) {
1269 case ISCSI_OP_SCSI_CMD_RSP:
1270 case ISCSI_OP_SCSI_DATA_IN:
1271 task = iscsi_itt_to_ctask(conn, hdr->itt);
1272 if (!task)
1273 return ISCSI_ERR_BAD_ITT;
1274 task->last_xfer = jiffies;
1275 break;
1276 case ISCSI_OP_R2T:
1277 /*
1278 * LLD handles R2Ts if they need to.
1279 */
1280 return 0;
1281 case ISCSI_OP_LOGOUT_RSP:
1282 case ISCSI_OP_LOGIN_RSP:
1283 case ISCSI_OP_TEXT_RSP:
1284 case ISCSI_OP_SCSI_TMFUNC_RSP:
1285 case ISCSI_OP_NOOP_IN:
1286 task = iscsi_itt_to_task(conn, hdr->itt);
1287 if (!task)
1288 return ISCSI_ERR_BAD_ITT;
1289 break;
1290 default:
1291 return ISCSI_ERR_BAD_OPCODE;
1292 }
1293
1294 switch(opcode) {
1295 case ISCSI_OP_SCSI_CMD_RSP:
1296 iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1297 break;
1298 case ISCSI_OP_SCSI_DATA_IN:
1299 iscsi_data_in_rsp(conn, hdr, task);
1300 break;
1301 case ISCSI_OP_LOGOUT_RSP:
1302 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1303 if (datalen) {
1304 rc = ISCSI_ERR_PROTO;
1305 break;
1306 }
1307 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1308 goto recv_pdu;
1309 case ISCSI_OP_LOGIN_RSP:
1310 case ISCSI_OP_TEXT_RSP:
1311 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1312 /*
1313 * login related PDU's exp_statsn is handled in
1314 * userspace
1315 */
1316 goto recv_pdu;
1317 case ISCSI_OP_SCSI_TMFUNC_RSP:
1318 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1319 if (datalen) {
1320 rc = ISCSI_ERR_PROTO;
1321 break;
1322 }
1323
1324 iscsi_tmf_rsp(conn, hdr);
1325 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1326 break;
1327 case ISCSI_OP_NOOP_IN:
1328 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1329 if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1330 rc = ISCSI_ERR_PROTO;
1331 break;
1332 }
1333 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1334
1335 rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1336 data, datalen);
1337 break;
1338 default:
1339 rc = ISCSI_ERR_BAD_OPCODE;
1340 break;
1341 }
1342
1343out:
1344 return rc;
1345recv_pdu:
1346 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1347 rc = ISCSI_ERR_CONN_FAILED;
1348 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1349 return rc;
1350}
1351EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1352
1353int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1354 char *data, int datalen)
1355{
1356 int rc;
1357
1358 spin_lock(&conn->session->back_lock);
1359 rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1360 spin_unlock(&conn->session->back_lock);
1361 return rc;
1362}
1363EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1364
1365int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1366{
1367 struct iscsi_session *session = conn->session;
1368 int age = 0, i = 0;
1369
1370 if (itt == RESERVED_ITT)
1371 return 0;
1372
1373 if (session->tt->parse_pdu_itt)
1374 session->tt->parse_pdu_itt(conn, itt, &i, &age);
1375 else {
1376 i = get_itt(itt);
1377 age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1378 }
1379
1380 if (age != session->age) {
1381 iscsi_conn_printk(KERN_ERR, conn,
1382 "received itt %x expected session age (%x)\n",
1383 (__force u32)itt, session->age);
1384 return ISCSI_ERR_BAD_ITT;
1385 }
1386
1387 if (i >= session->cmds_max) {
1388 iscsi_conn_printk(KERN_ERR, conn,
1389 "received invalid itt index %u (max cmds "
1390 "%u.\n", i, session->cmds_max);
1391 return ISCSI_ERR_BAD_ITT;
1392 }
1393 return 0;
1394}
1395EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1396
1397/**
1398 * iscsi_itt_to_ctask - look up ctask by itt
1399 * @conn: iscsi connection
1400 * @itt: itt
1401 *
1402 * This should be used for cmd tasks.
1403 *
1404 * The session back_lock must be held.
1405 */
1406struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1407{
1408 struct iscsi_task *task;
1409
1410 if (iscsi_verify_itt(conn, itt))
1411 return NULL;
1412
1413 task = iscsi_itt_to_task(conn, itt);
1414 if (!task || !task->sc)
1415 return NULL;
1416
1417 if (iscsi_cmd(task->sc)->age != conn->session->age) {
1418 iscsi_session_printk(KERN_ERR, conn->session,
1419 "task's session age %d, expected %d\n",
1420 iscsi_cmd(task->sc)->age, conn->session->age);
1421 return NULL;
1422 }
1423
1424 return task;
1425}
1426EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1427
1428void iscsi_session_failure(struct iscsi_session *session,
1429 enum iscsi_err err)
1430{
1431 struct iscsi_conn *conn;
1432
1433 spin_lock_bh(&session->frwd_lock);
1434 conn = session->leadconn;
1435 if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1436 spin_unlock_bh(&session->frwd_lock);
1437 return;
1438 }
1439
1440 iscsi_get_conn(conn->cls_conn);
1441 spin_unlock_bh(&session->frwd_lock);
1442 /*
1443 * if the host is being removed bypass the connection
1444 * recovery initialization because we are going to kill
1445 * the session.
1446 */
1447 if (err == ISCSI_ERR_INVALID_HOST)
1448 iscsi_conn_error_event(conn->cls_conn, err);
1449 else
1450 iscsi_conn_failure(conn, err);
1451 iscsi_put_conn(conn->cls_conn);
1452}
1453EXPORT_SYMBOL_GPL(iscsi_session_failure);
1454
1455static bool iscsi_set_conn_failed(struct iscsi_conn *conn)
1456{
1457 struct iscsi_session *session = conn->session;
1458
1459 if (session->state == ISCSI_STATE_FAILED)
1460 return false;
1461
1462 if (conn->stop_stage == 0)
1463 session->state = ISCSI_STATE_FAILED;
1464
1465 set_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags);
1466 set_bit(ISCSI_CONN_FLAG_SUSPEND_RX, &conn->flags);
1467 return true;
1468}
1469
1470void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1471{
1472 struct iscsi_session *session = conn->session;
1473 bool needs_evt;
1474
1475 spin_lock_bh(&session->frwd_lock);
1476 needs_evt = iscsi_set_conn_failed(conn);
1477 spin_unlock_bh(&session->frwd_lock);
1478
1479 if (needs_evt)
1480 iscsi_conn_error_event(conn->cls_conn, err);
1481}
1482EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1483
1484static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1485{
1486 struct iscsi_session *session = conn->session;
1487
1488 /*
1489 * Check for iSCSI window and take care of CmdSN wrap-around
1490 */
1491 if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1492 ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1493 "%u MaxCmdSN %u CmdSN %u/%u\n",
1494 session->exp_cmdsn, session->max_cmdsn,
1495 session->cmdsn, session->queued_cmdsn);
1496 return -ENOSPC;
1497 }
1498 return 0;
1499}
1500
1501static int iscsi_xmit_task(struct iscsi_conn *conn, struct iscsi_task *task,
1502 bool was_requeue)
1503{
1504 int rc;
1505
1506 if (!conn->task) {
1507 /*
1508 * Take a ref so we can access it after xmit_task().
1509 *
1510 * This should never fail because the failure paths will have
1511 * stopped the xmit thread.
1512 */
1513 if (!iscsi_get_task(task)) {
1514 WARN_ON_ONCE(1);
1515 return 0;
1516 }
1517 } else {
1518 /* Already have a ref from when we failed to send it last call */
1519 conn->task = NULL;
1520 }
1521
1522 /*
1523 * If this was a requeue for a R2T we have an extra ref on the task in
1524 * case a bad target sends a cmd rsp before we have handled the task.
1525 */
1526 if (was_requeue)
1527 iscsi_put_task(task);
1528
1529 /*
1530 * Do this after dropping the extra ref because if this was a requeue
1531 * it's removed from that list and cleanup_queued_task would miss it.
1532 */
1533 if (test_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags)) {
1534 /*
1535 * Save the task and ref in case we weren't cleaning up this
1536 * task and get woken up again.
1537 */
1538 conn->task = task;
1539 return -ENODATA;
1540 }
1541
1542 spin_unlock_bh(&conn->session->frwd_lock);
1543 rc = conn->session->tt->xmit_task(task);
1544 spin_lock_bh(&conn->session->frwd_lock);
1545 if (!rc) {
1546 /* done with this task */
1547 task->last_xfer = jiffies;
1548 } else {
1549 /*
1550 * get an extra ref that is released next time we access it
1551 * as conn->task above.
1552 */
1553 iscsi_get_task(task);
1554 conn->task = task;
1555 }
1556
1557 iscsi_put_task(task);
1558 return rc;
1559}
1560
1561/**
1562 * iscsi_requeue_task - requeue task to run from session workqueue
1563 * @task: task to requeue
1564 *
1565 * Callers must have taken a ref to the task that is going to be requeued.
1566 */
1567void iscsi_requeue_task(struct iscsi_task *task)
1568{
1569 struct iscsi_conn *conn = task->conn;
1570
1571 /*
1572 * this may be on the requeue list already if the xmit_task callout
1573 * is handling the r2ts while we are adding new ones
1574 */
1575 spin_lock_bh(&conn->session->frwd_lock);
1576 if (list_empty(&task->running)) {
1577 list_add_tail(&task->running, &conn->requeue);
1578 } else {
1579 /*
1580 * Don't need the extra ref since it's already requeued and
1581 * has a ref.
1582 */
1583 iscsi_put_task(task);
1584 }
1585 iscsi_conn_queue_xmit(conn);
1586 spin_unlock_bh(&conn->session->frwd_lock);
1587}
1588EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1589
1590/**
1591 * iscsi_data_xmit - xmit any command into the scheduled connection
1592 * @conn: iscsi connection
1593 *
1594 * Notes:
1595 * The function can return -EAGAIN in which case the caller must
1596 * re-schedule it again later or recover. '0' return code means
1597 * successful xmit.
1598 **/
1599static int iscsi_data_xmit(struct iscsi_conn *conn)
1600{
1601 struct iscsi_task *task;
1602 int rc = 0;
1603
1604 spin_lock_bh(&conn->session->frwd_lock);
1605 if (test_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags)) {
1606 ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1607 spin_unlock_bh(&conn->session->frwd_lock);
1608 return -ENODATA;
1609 }
1610
1611 if (conn->task) {
1612 rc = iscsi_xmit_task(conn, conn->task, false);
1613 if (rc)
1614 goto done;
1615 }
1616
1617 /*
1618 * process mgmt pdus like nops before commands since we should
1619 * only have one nop-out as a ping from us and targets should not
1620 * overflow us with nop-ins
1621 */
1622check_mgmt:
1623 while (!list_empty(&conn->mgmtqueue)) {
1624 task = list_entry(conn->mgmtqueue.next, struct iscsi_task,
1625 running);
1626 list_del_init(&task->running);
1627 if (iscsi_prep_mgmt_task(conn, task)) {
1628 /* regular RX path uses back_lock */
1629 spin_lock_bh(&conn->session->back_lock);
1630 __iscsi_put_task(task);
1631 spin_unlock_bh(&conn->session->back_lock);
1632 continue;
1633 }
1634 rc = iscsi_xmit_task(conn, task, false);
1635 if (rc)
1636 goto done;
1637 }
1638
1639check_requeue:
1640 while (!list_empty(&conn->requeue)) {
1641 /*
1642 * we always do fastlogout - conn stop code will clean up.
1643 */
1644 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1645 break;
1646
1647 task = list_entry(conn->requeue.next, struct iscsi_task,
1648 running);
1649
1650 if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1651 break;
1652
1653 list_del_init(&task->running);
1654 rc = iscsi_xmit_task(conn, task, true);
1655 if (rc)
1656 goto done;
1657 if (!list_empty(&conn->mgmtqueue))
1658 goto check_mgmt;
1659 }
1660
1661 /* process pending command queue */
1662 while (!list_empty(&conn->cmdqueue)) {
1663 task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1664 running);
1665 list_del_init(&task->running);
1666 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1667 fail_scsi_task(task, DID_IMM_RETRY);
1668 continue;
1669 }
1670 rc = iscsi_prep_scsi_cmd_pdu(task);
1671 if (rc) {
1672 if (rc == -ENOMEM || rc == -EACCES)
1673 fail_scsi_task(task, DID_IMM_RETRY);
1674 else
1675 fail_scsi_task(task, DID_ABORT);
1676 continue;
1677 }
1678 rc = iscsi_xmit_task(conn, task, false);
1679 if (rc)
1680 goto done;
1681 /*
1682 * we could continuously get new task requests so
1683 * we need to check the mgmt queue for nops that need to
1684 * be sent to aviod starvation
1685 */
1686 if (!list_empty(&conn->mgmtqueue))
1687 goto check_mgmt;
1688 if (!list_empty(&conn->requeue))
1689 goto check_requeue;
1690 }
1691
1692 spin_unlock_bh(&conn->session->frwd_lock);
1693 return -ENODATA;
1694
1695done:
1696 spin_unlock_bh(&conn->session->frwd_lock);
1697 return rc;
1698}
1699
1700static void iscsi_xmitworker(struct work_struct *work)
1701{
1702 struct iscsi_conn *conn =
1703 container_of(work, struct iscsi_conn, xmitwork);
1704 int rc;
1705 /*
1706 * serialize Xmit worker on a per-connection basis.
1707 */
1708 do {
1709 rc = iscsi_data_xmit(conn);
1710 } while (rc >= 0 || rc == -EAGAIN);
1711}
1712
1713static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1714 struct scsi_cmnd *sc)
1715{
1716 struct iscsi_task *task;
1717
1718 if (!kfifo_out(&conn->session->cmdpool.queue,
1719 (void *) &task, sizeof(void *)))
1720 return NULL;
1721
1722 iscsi_cmd(sc)->age = conn->session->age;
1723 iscsi_cmd(sc)->task = task;
1724
1725 refcount_set(&task->refcount, 1);
1726 task->state = ISCSI_TASK_PENDING;
1727 task->conn = conn;
1728 task->sc = sc;
1729 task->have_checked_conn = false;
1730 task->last_timeout = jiffies;
1731 task->last_xfer = jiffies;
1732 task->protected = false;
1733 INIT_LIST_HEAD(&task->running);
1734 return task;
1735}
1736
1737enum {
1738 FAILURE_BAD_HOST = 1,
1739 FAILURE_SESSION_FAILED,
1740 FAILURE_SESSION_FREED,
1741 FAILURE_WINDOW_CLOSED,
1742 FAILURE_OOM,
1743 FAILURE_SESSION_TERMINATE,
1744 FAILURE_SESSION_IN_RECOVERY,
1745 FAILURE_SESSION_RECOVERY_TIMEOUT,
1746 FAILURE_SESSION_LOGGING_OUT,
1747 FAILURE_SESSION_NOT_READY,
1748};
1749
1750int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1751{
1752 struct iscsi_cls_session *cls_session;
1753 struct iscsi_host *ihost;
1754 int reason = 0;
1755 struct iscsi_session *session;
1756 struct iscsi_conn *conn;
1757 struct iscsi_task *task = NULL;
1758
1759 sc->result = 0;
1760 iscsi_cmd(sc)->task = NULL;
1761
1762 ihost = shost_priv(host);
1763
1764 cls_session = starget_to_session(scsi_target(sc->device));
1765 session = cls_session->dd_data;
1766 spin_lock_bh(&session->frwd_lock);
1767
1768 reason = iscsi_session_chkready(cls_session);
1769 if (reason) {
1770 sc->result = reason;
1771 goto fault;
1772 }
1773
1774 if (session->state != ISCSI_STATE_LOGGED_IN) {
1775 /*
1776 * to handle the race between when we set the recovery state
1777 * and block the session we requeue here (commands could
1778 * be entering our queuecommand while a block is starting
1779 * up because the block code is not locked)
1780 */
1781 switch (session->state) {
1782 case ISCSI_STATE_FAILED:
1783 /*
1784 * cmds should fail during shutdown, if the session
1785 * state is bad, allowing completion to happen
1786 */
1787 if (unlikely(system_state != SYSTEM_RUNNING)) {
1788 reason = FAILURE_SESSION_FAILED;
1789 sc->result = DID_NO_CONNECT << 16;
1790 break;
1791 }
1792 fallthrough;
1793 case ISCSI_STATE_IN_RECOVERY:
1794 reason = FAILURE_SESSION_IN_RECOVERY;
1795 sc->result = DID_IMM_RETRY << 16;
1796 break;
1797 case ISCSI_STATE_LOGGING_OUT:
1798 reason = FAILURE_SESSION_LOGGING_OUT;
1799 sc->result = DID_IMM_RETRY << 16;
1800 break;
1801 case ISCSI_STATE_RECOVERY_FAILED:
1802 reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1803 sc->result = DID_TRANSPORT_FAILFAST << 16;
1804 break;
1805 case ISCSI_STATE_TERMINATE:
1806 reason = FAILURE_SESSION_TERMINATE;
1807 sc->result = DID_NO_CONNECT << 16;
1808 break;
1809 default:
1810 reason = FAILURE_SESSION_FREED;
1811 sc->result = DID_NO_CONNECT << 16;
1812 }
1813 goto fault;
1814 }
1815
1816 conn = session->leadconn;
1817 if (!conn) {
1818 reason = FAILURE_SESSION_FREED;
1819 sc->result = DID_NO_CONNECT << 16;
1820 goto fault;
1821 }
1822
1823 if (test_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags)) {
1824 reason = FAILURE_SESSION_IN_RECOVERY;
1825 sc->result = DID_REQUEUE << 16;
1826 goto fault;
1827 }
1828
1829 if (iscsi_check_cmdsn_window_closed(conn)) {
1830 reason = FAILURE_WINDOW_CLOSED;
1831 goto reject;
1832 }
1833
1834 task = iscsi_alloc_task(conn, sc);
1835 if (!task) {
1836 reason = FAILURE_OOM;
1837 goto reject;
1838 }
1839
1840 if (!ihost->workq) {
1841 reason = iscsi_prep_scsi_cmd_pdu(task);
1842 if (reason) {
1843 if (reason == -ENOMEM || reason == -EACCES) {
1844 reason = FAILURE_OOM;
1845 goto prepd_reject;
1846 } else {
1847 sc->result = DID_ABORT << 16;
1848 goto prepd_fault;
1849 }
1850 }
1851 if (session->tt->xmit_task(task)) {
1852 session->cmdsn--;
1853 reason = FAILURE_SESSION_NOT_READY;
1854 goto prepd_reject;
1855 }
1856 } else {
1857 list_add_tail(&task->running, &conn->cmdqueue);
1858 iscsi_conn_queue_xmit(conn);
1859 }
1860
1861 session->queued_cmdsn++;
1862 spin_unlock_bh(&session->frwd_lock);
1863 return 0;
1864
1865prepd_reject:
1866 spin_lock_bh(&session->back_lock);
1867 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1868 spin_unlock_bh(&session->back_lock);
1869reject:
1870 spin_unlock_bh(&session->frwd_lock);
1871 ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1872 sc->cmnd[0], reason);
1873 return SCSI_MLQUEUE_TARGET_BUSY;
1874
1875prepd_fault:
1876 spin_lock_bh(&session->back_lock);
1877 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1878 spin_unlock_bh(&session->back_lock);
1879fault:
1880 spin_unlock_bh(&session->frwd_lock);
1881 ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1882 sc->cmnd[0], reason);
1883 scsi_set_resid(sc, scsi_bufflen(sc));
1884 scsi_done(sc);
1885 return 0;
1886}
1887EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1888
1889int iscsi_target_alloc(struct scsi_target *starget)
1890{
1891 struct iscsi_cls_session *cls_session = starget_to_session(starget);
1892 struct iscsi_session *session = cls_session->dd_data;
1893
1894 starget->can_queue = session->scsi_cmds_max;
1895 return 0;
1896}
1897EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1898
1899static void iscsi_tmf_timedout(struct timer_list *t)
1900{
1901 struct iscsi_session *session = from_timer(session, t, tmf_timer);
1902
1903 spin_lock(&session->frwd_lock);
1904 if (session->tmf_state == TMF_QUEUED) {
1905 session->tmf_state = TMF_TIMEDOUT;
1906 ISCSI_DBG_EH(session, "tmf timedout\n");
1907 /* unblock eh_abort() */
1908 wake_up(&session->ehwait);
1909 }
1910 spin_unlock(&session->frwd_lock);
1911}
1912
1913static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1914 struct iscsi_tm *hdr, int age,
1915 int timeout)
1916 __must_hold(&session->frwd_lock)
1917{
1918 struct iscsi_session *session = conn->session;
1919
1920 if (__iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr, NULL, 0)) {
1921 spin_unlock_bh(&session->frwd_lock);
1922 iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1923 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1924 spin_lock_bh(&session->frwd_lock);
1925 return -EPERM;
1926 }
1927 conn->tmfcmd_pdus_cnt++;
1928 session->tmf_timer.expires = timeout * HZ + jiffies;
1929 add_timer(&session->tmf_timer);
1930 ISCSI_DBG_EH(session, "tmf set timeout\n");
1931
1932 spin_unlock_bh(&session->frwd_lock);
1933 mutex_unlock(&session->eh_mutex);
1934
1935 /*
1936 * block eh thread until:
1937 *
1938 * 1) tmf response
1939 * 2) tmf timeout
1940 * 3) session is terminated or restarted or userspace has
1941 * given up on recovery
1942 */
1943 wait_event_interruptible(session->ehwait, age != session->age ||
1944 session->state != ISCSI_STATE_LOGGED_IN ||
1945 session->tmf_state != TMF_QUEUED);
1946 if (signal_pending(current))
1947 flush_signals(current);
1948 del_timer_sync(&session->tmf_timer);
1949
1950 mutex_lock(&session->eh_mutex);
1951 spin_lock_bh(&session->frwd_lock);
1952 /* if the session drops it will clean up the task */
1953 if (age != session->age ||
1954 session->state != ISCSI_STATE_LOGGED_IN)
1955 return -ENOTCONN;
1956 return 0;
1957}
1958
1959/*
1960 * Fail commands. session frwd lock held and xmit thread flushed.
1961 */
1962static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error)
1963{
1964 struct iscsi_session *session = conn->session;
1965 struct iscsi_task *task;
1966 int i;
1967
1968restart_cmd_loop:
1969 spin_lock_bh(&session->back_lock);
1970 for (i = 0; i < session->cmds_max; i++) {
1971 task = session->cmds[i];
1972 if (!task->sc || task->state == ISCSI_TASK_FREE)
1973 continue;
1974
1975 if (lun != -1 && lun != task->sc->device->lun)
1976 continue;
1977 /*
1978 * The cmd is completing but if this is called from an eh
1979 * callout path then when we return scsi-ml owns the cmd. Wait
1980 * for the completion path to finish freeing the cmd.
1981 */
1982 if (!iscsi_get_task(task)) {
1983 spin_unlock_bh(&session->back_lock);
1984 spin_unlock_bh(&session->frwd_lock);
1985 udelay(ISCSI_CMD_COMPL_WAIT);
1986 spin_lock_bh(&session->frwd_lock);
1987 goto restart_cmd_loop;
1988 }
1989
1990 ISCSI_DBG_SESSION(session,
1991 "failing sc %p itt 0x%x state %d\n",
1992 task->sc, task->itt, task->state);
1993 __fail_scsi_task(task, error);
1994 __iscsi_put_task(task);
1995 }
1996 spin_unlock_bh(&session->back_lock);
1997}
1998
1999/**
2000 * iscsi_suspend_queue - suspend iscsi_queuecommand
2001 * @conn: iscsi conn to stop queueing IO on
2002 *
2003 * This grabs the session frwd_lock to make sure no one is in
2004 * xmit_task/queuecommand, and then sets suspend to prevent
2005 * new commands from being queued. This only needs to be called
2006 * by offload drivers that need to sync a path like ep disconnect
2007 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
2008 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
2009 */
2010void iscsi_suspend_queue(struct iscsi_conn *conn)
2011{
2012 spin_lock_bh(&conn->session->frwd_lock);
2013 set_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags);
2014 spin_unlock_bh(&conn->session->frwd_lock);
2015}
2016EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
2017
2018/**
2019 * iscsi_suspend_tx - suspend iscsi_data_xmit
2020 * @conn: iscsi conn to stop processing IO on.
2021 *
2022 * This function sets the suspend bit to prevent iscsi_data_xmit
2023 * from sending new IO, and if work is queued on the xmit thread
2024 * it will wait for it to be completed.
2025 */
2026void iscsi_suspend_tx(struct iscsi_conn *conn)
2027{
2028 struct Scsi_Host *shost = conn->session->host;
2029 struct iscsi_host *ihost = shost_priv(shost);
2030
2031 set_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags);
2032 if (ihost->workq)
2033 flush_work(&conn->xmitwork);
2034}
2035EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
2036
2037static void iscsi_start_tx(struct iscsi_conn *conn)
2038{
2039 clear_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags);
2040 iscsi_conn_queue_xmit(conn);
2041}
2042
2043/**
2044 * iscsi_suspend_rx - Prevent recvwork from running again.
2045 * @conn: iscsi conn to stop.
2046 */
2047void iscsi_suspend_rx(struct iscsi_conn *conn)
2048{
2049 struct Scsi_Host *shost = conn->session->host;
2050 struct iscsi_host *ihost = shost_priv(shost);
2051
2052 set_bit(ISCSI_CONN_FLAG_SUSPEND_RX, &conn->flags);
2053 if (ihost->workq)
2054 flush_work(&conn->recvwork);
2055}
2056EXPORT_SYMBOL_GPL(iscsi_suspend_rx);
2057
2058/*
2059 * We want to make sure a ping is in flight. It has timed out.
2060 * And we are not busy processing a pdu that is making
2061 * progress but got started before the ping and is taking a while
2062 * to complete so the ping is just stuck behind it in a queue.
2063 */
2064static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
2065{
2066 if (READ_ONCE(conn->ping_task) &&
2067 time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
2068 (conn->ping_timeout * HZ), jiffies))
2069 return 1;
2070 else
2071 return 0;
2072}
2073
2074enum scsi_timeout_action iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
2075{
2076 enum scsi_timeout_action rc = SCSI_EH_NOT_HANDLED;
2077 struct iscsi_task *task = NULL, *running_task;
2078 struct iscsi_cls_session *cls_session;
2079 struct iscsi_session *session;
2080 struct iscsi_conn *conn;
2081 int i;
2082
2083 cls_session = starget_to_session(scsi_target(sc->device));
2084 session = cls_session->dd_data;
2085
2086 ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
2087
2088 spin_lock_bh(&session->frwd_lock);
2089 spin_lock(&session->back_lock);
2090 task = iscsi_cmd(sc)->task;
2091 if (!task) {
2092 /*
2093 * Raced with completion. Blk layer has taken ownership
2094 * so let timeout code complete it now.
2095 */
2096 rc = SCSI_EH_NOT_HANDLED;
2097 spin_unlock(&session->back_lock);
2098 goto done;
2099 }
2100 if (!iscsi_get_task(task)) {
2101 /*
2102 * Racing with the completion path right now, so give it more
2103 * time so that path can complete it like normal.
2104 */
2105 rc = SCSI_EH_RESET_TIMER;
2106 task = NULL;
2107 spin_unlock(&session->back_lock);
2108 goto done;
2109 }
2110 spin_unlock(&session->back_lock);
2111
2112 if (session->state != ISCSI_STATE_LOGGED_IN) {
2113 /*
2114 * During shutdown, if session is prematurely disconnected,
2115 * recovery won't happen and there will be hung cmds. Not
2116 * handling cmds would trigger EH, also bad in this case.
2117 * Instead, handle cmd, allow completion to happen and let
2118 * upper layer to deal with the result.
2119 */
2120 if (unlikely(system_state != SYSTEM_RUNNING)) {
2121 sc->result = DID_NO_CONNECT << 16;
2122 ISCSI_DBG_EH(session, "sc on shutdown, handled\n");
2123 rc = SCSI_EH_NOT_HANDLED;
2124 goto done;
2125 }
2126 /*
2127 * We are probably in the middle of iscsi recovery so let
2128 * that complete and handle the error.
2129 */
2130 rc = SCSI_EH_RESET_TIMER;
2131 goto done;
2132 }
2133
2134 conn = session->leadconn;
2135 if (!conn) {
2136 /* In the middle of shuting down */
2137 rc = SCSI_EH_RESET_TIMER;
2138 goto done;
2139 }
2140
2141 /*
2142 * If we have sent (at least queued to the network layer) a pdu or
2143 * recvd one for the task since the last timeout ask for
2144 * more time. If on the next timeout we have not made progress
2145 * we can check if it is the task or connection when we send the
2146 * nop as a ping.
2147 */
2148 if (time_after(task->last_xfer, task->last_timeout)) {
2149 ISCSI_DBG_EH(session, "Command making progress. Asking "
2150 "scsi-ml for more time to complete. "
2151 "Last data xfer at %lu. Last timeout was at "
2152 "%lu\n.", task->last_xfer, task->last_timeout);
2153 task->have_checked_conn = false;
2154 rc = SCSI_EH_RESET_TIMER;
2155 goto done;
2156 }
2157
2158 if (!conn->recv_timeout && !conn->ping_timeout)
2159 goto done;
2160 /*
2161 * if the ping timedout then we are in the middle of cleaning up
2162 * and can let the iscsi eh handle it
2163 */
2164 if (iscsi_has_ping_timed_out(conn)) {
2165 rc = SCSI_EH_RESET_TIMER;
2166 goto done;
2167 }
2168
2169 spin_lock(&session->back_lock);
2170 for (i = 0; i < conn->session->cmds_max; i++) {
2171 running_task = conn->session->cmds[i];
2172 if (!running_task->sc || running_task == task ||
2173 running_task->state != ISCSI_TASK_RUNNING)
2174 continue;
2175
2176 /*
2177 * Only check if cmds started before this one have made
2178 * progress, or this could never fail
2179 */
2180 if (time_after(running_task->sc->jiffies_at_alloc,
2181 task->sc->jiffies_at_alloc))
2182 continue;
2183
2184 if (time_after(running_task->last_xfer, task->last_timeout)) {
2185 /*
2186 * This task has not made progress, but a task
2187 * started before us has transferred data since
2188 * we started/last-checked. We could be queueing
2189 * too many tasks or the LU is bad.
2190 *
2191 * If the device is bad the cmds ahead of us on
2192 * other devs will complete, and this loop will
2193 * eventually fail starting the scsi eh.
2194 */
2195 ISCSI_DBG_EH(session, "Command has not made progress "
2196 "but commands ahead of it have. "
2197 "Asking scsi-ml for more time to "
2198 "complete. Our last xfer vs running task "
2199 "last xfer %lu/%lu. Last check %lu.\n",
2200 task->last_xfer, running_task->last_xfer,
2201 task->last_timeout);
2202 spin_unlock(&session->back_lock);
2203 rc = SCSI_EH_RESET_TIMER;
2204 goto done;
2205 }
2206 }
2207 spin_unlock(&session->back_lock);
2208
2209 /* Assumes nop timeout is shorter than scsi cmd timeout */
2210 if (task->have_checked_conn)
2211 goto done;
2212
2213 /*
2214 * Checking the transport already or nop from a cmd timeout still
2215 * running
2216 */
2217 if (READ_ONCE(conn->ping_task)) {
2218 task->have_checked_conn = true;
2219 rc = SCSI_EH_RESET_TIMER;
2220 goto done;
2221 }
2222
2223 /* Make sure there is a transport check done */
2224 iscsi_send_nopout(conn, NULL);
2225 task->have_checked_conn = true;
2226 rc = SCSI_EH_RESET_TIMER;
2227
2228done:
2229 spin_unlock_bh(&session->frwd_lock);
2230
2231 if (task) {
2232 task->last_timeout = jiffies;
2233 iscsi_put_task(task);
2234 }
2235 ISCSI_DBG_EH(session, "return %s\n", rc == SCSI_EH_RESET_TIMER ?
2236 "timer reset" : "shutdown or nh");
2237 return rc;
2238}
2239EXPORT_SYMBOL_GPL(iscsi_eh_cmd_timed_out);
2240
2241static void iscsi_check_transport_timeouts(struct timer_list *t)
2242{
2243 struct iscsi_conn *conn = from_timer(conn, t, transport_timer);
2244 struct iscsi_session *session = conn->session;
2245 unsigned long recv_timeout, next_timeout = 0, last_recv;
2246
2247 spin_lock(&session->frwd_lock);
2248 if (session->state != ISCSI_STATE_LOGGED_IN)
2249 goto done;
2250
2251 recv_timeout = conn->recv_timeout;
2252 if (!recv_timeout)
2253 goto done;
2254
2255 recv_timeout *= HZ;
2256 last_recv = conn->last_recv;
2257
2258 if (iscsi_has_ping_timed_out(conn)) {
2259 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2260 "expired, recv timeout %d, last rx %lu, "
2261 "last ping %lu, now %lu\n",
2262 conn->ping_timeout, conn->recv_timeout,
2263 last_recv, conn->last_ping, jiffies);
2264 spin_unlock(&session->frwd_lock);
2265 iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT);
2266 return;
2267 }
2268
2269 if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2270 /* send a ping to try to provoke some traffic */
2271 ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2272 if (iscsi_send_nopout(conn, NULL))
2273 next_timeout = jiffies + (1 * HZ);
2274 else
2275 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2276 } else
2277 next_timeout = last_recv + recv_timeout;
2278
2279 ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2280 mod_timer(&conn->transport_timer, next_timeout);
2281done:
2282 spin_unlock(&session->frwd_lock);
2283}
2284
2285/**
2286 * iscsi_conn_unbind - prevent queueing to conn.
2287 * @cls_conn: iscsi conn ep is bound to.
2288 * @is_active: is the conn in use for boot or is this for EH/termination
2289 *
2290 * This must be called by drivers implementing the ep_disconnect callout.
2291 * It disables queueing to the connection from libiscsi in preparation for
2292 * an ep_disconnect call.
2293 */
2294void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active)
2295{
2296 struct iscsi_session *session;
2297 struct iscsi_conn *conn;
2298
2299 if (!cls_conn)
2300 return;
2301
2302 conn = cls_conn->dd_data;
2303 session = conn->session;
2304 /*
2305 * Wait for iscsi_eh calls to exit. We don't wait for the tmf to
2306 * complete or timeout. The caller just wants to know what's running
2307 * is everything that needs to be cleaned up, and no cmds will be
2308 * queued.
2309 */
2310 mutex_lock(&session->eh_mutex);
2311
2312 iscsi_suspend_queue(conn);
2313 iscsi_suspend_tx(conn);
2314
2315 spin_lock_bh(&session->frwd_lock);
2316 clear_bit(ISCSI_CONN_FLAG_BOUND, &conn->flags);
2317
2318 if (!is_active) {
2319 /*
2320 * if logout timed out before userspace could even send a PDU
2321 * the state might still be in ISCSI_STATE_LOGGED_IN and
2322 * allowing new cmds and TMFs.
2323 */
2324 if (session->state == ISCSI_STATE_LOGGED_IN)
2325 iscsi_set_conn_failed(conn);
2326 }
2327 spin_unlock_bh(&session->frwd_lock);
2328 mutex_unlock(&session->eh_mutex);
2329}
2330EXPORT_SYMBOL_GPL(iscsi_conn_unbind);
2331
2332static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2333 struct iscsi_tm *hdr)
2334{
2335 memset(hdr, 0, sizeof(*hdr));
2336 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2337 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2338 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2339 hdr->lun = task->lun;
2340 hdr->rtt = task->hdr_itt;
2341 hdr->refcmdsn = task->cmdsn;
2342}
2343
2344int iscsi_eh_abort(struct scsi_cmnd *sc)
2345{
2346 struct iscsi_cls_session *cls_session;
2347 struct iscsi_session *session;
2348 struct iscsi_conn *conn;
2349 struct iscsi_task *task;
2350 struct iscsi_tm *hdr;
2351 int age;
2352
2353 cls_session = starget_to_session(scsi_target(sc->device));
2354 session = cls_session->dd_data;
2355
2356 ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2357
2358completion_check:
2359 mutex_lock(&session->eh_mutex);
2360 spin_lock_bh(&session->frwd_lock);
2361 /*
2362 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2363 * got the command.
2364 */
2365 if (!iscsi_cmd(sc)->task) {
2366 ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2367 "it completed.\n");
2368 spin_unlock_bh(&session->frwd_lock);
2369 mutex_unlock(&session->eh_mutex);
2370 return SUCCESS;
2371 }
2372
2373 /*
2374 * If we are not logged in or we have started a new session
2375 * then let the host reset code handle this
2376 */
2377 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2378 iscsi_cmd(sc)->age != session->age) {
2379 spin_unlock_bh(&session->frwd_lock);
2380 mutex_unlock(&session->eh_mutex);
2381 ISCSI_DBG_EH(session, "failing abort due to dropped "
2382 "session.\n");
2383 return FAILED;
2384 }
2385
2386 spin_lock(&session->back_lock);
2387 task = iscsi_cmd(sc)->task;
2388 if (!task || !task->sc) {
2389 /* task completed before time out */
2390 ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2391
2392 spin_unlock(&session->back_lock);
2393 spin_unlock_bh(&session->frwd_lock);
2394 mutex_unlock(&session->eh_mutex);
2395 return SUCCESS;
2396 }
2397
2398 if (!iscsi_get_task(task)) {
2399 spin_unlock(&session->back_lock);
2400 spin_unlock_bh(&session->frwd_lock);
2401 mutex_unlock(&session->eh_mutex);
2402 /* We are just about to call iscsi_free_task so wait for it. */
2403 udelay(ISCSI_CMD_COMPL_WAIT);
2404 goto completion_check;
2405 }
2406
2407 ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n", sc, task->itt);
2408 conn = session->leadconn;
2409 iscsi_get_conn(conn->cls_conn);
2410 conn->eh_abort_cnt++;
2411 age = session->age;
2412 spin_unlock(&session->back_lock);
2413
2414 if (task->state == ISCSI_TASK_PENDING) {
2415 fail_scsi_task(task, DID_ABORT);
2416 goto success;
2417 }
2418
2419 /* only have one tmf outstanding at a time */
2420 if (session->tmf_state != TMF_INITIAL)
2421 goto failed;
2422 session->tmf_state = TMF_QUEUED;
2423
2424 hdr = &session->tmhdr;
2425 iscsi_prep_abort_task_pdu(task, hdr);
2426
2427 if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout))
2428 goto failed;
2429
2430 switch (session->tmf_state) {
2431 case TMF_SUCCESS:
2432 spin_unlock_bh(&session->frwd_lock);
2433 /*
2434 * stop tx side incase the target had sent a abort rsp but
2435 * the initiator was still writing out data.
2436 */
2437 iscsi_suspend_tx(conn);
2438 /*
2439 * we do not stop the recv side because targets have been
2440 * good and have never sent us a successful tmf response
2441 * then sent more data for the cmd.
2442 */
2443 spin_lock_bh(&session->frwd_lock);
2444 fail_scsi_task(task, DID_ABORT);
2445 session->tmf_state = TMF_INITIAL;
2446 memset(hdr, 0, sizeof(*hdr));
2447 spin_unlock_bh(&session->frwd_lock);
2448 iscsi_start_tx(conn);
2449 goto success_unlocked;
2450 case TMF_TIMEDOUT:
2451 session->running_aborted_task = task;
2452 spin_unlock_bh(&session->frwd_lock);
2453 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2454 goto failed_unlocked;
2455 case TMF_NOT_FOUND:
2456 if (iscsi_task_is_completed(task)) {
2457 session->tmf_state = TMF_INITIAL;
2458 memset(hdr, 0, sizeof(*hdr));
2459 /* task completed before tmf abort response */
2460 ISCSI_DBG_EH(session, "sc completed while abort in "
2461 "progress\n");
2462 goto success;
2463 }
2464 fallthrough;
2465 default:
2466 session->tmf_state = TMF_INITIAL;
2467 goto failed;
2468 }
2469
2470success:
2471 spin_unlock_bh(&session->frwd_lock);
2472success_unlocked:
2473 ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2474 sc, task->itt);
2475 iscsi_put_task(task);
2476 iscsi_put_conn(conn->cls_conn);
2477 mutex_unlock(&session->eh_mutex);
2478 return SUCCESS;
2479
2480failed:
2481 spin_unlock_bh(&session->frwd_lock);
2482failed_unlocked:
2483 ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2484 task ? task->itt : 0);
2485 /*
2486 * The driver might be accessing the task so hold the ref. The conn
2487 * stop cleanup will drop the ref after ep_disconnect so we know the
2488 * driver's no longer touching the task.
2489 */
2490 if (!session->running_aborted_task)
2491 iscsi_put_task(task);
2492
2493 iscsi_put_conn(conn->cls_conn);
2494 mutex_unlock(&session->eh_mutex);
2495 return FAILED;
2496}
2497EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2498
2499static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2500{
2501 memset(hdr, 0, sizeof(*hdr));
2502 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2503 hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2504 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2505 int_to_scsilun(sc->device->lun, &hdr->lun);
2506 hdr->rtt = RESERVED_ITT;
2507}
2508
2509int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2510{
2511 struct iscsi_cls_session *cls_session;
2512 struct iscsi_session *session;
2513 struct iscsi_conn *conn;
2514 struct iscsi_tm *hdr;
2515 int rc = FAILED;
2516
2517 cls_session = starget_to_session(scsi_target(sc->device));
2518 session = cls_session->dd_data;
2519
2520 ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc,
2521 sc->device->lun);
2522
2523 mutex_lock(&session->eh_mutex);
2524 spin_lock_bh(&session->frwd_lock);
2525 /*
2526 * Just check if we are not logged in. We cannot check for
2527 * the phase because the reset could come from a ioctl.
2528 */
2529 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2530 goto unlock;
2531 conn = session->leadconn;
2532
2533 /* only have one tmf outstanding at a time */
2534 if (session->tmf_state != TMF_INITIAL)
2535 goto unlock;
2536 session->tmf_state = TMF_QUEUED;
2537
2538 hdr = &session->tmhdr;
2539 iscsi_prep_lun_reset_pdu(sc, hdr);
2540
2541 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2542 session->lu_reset_timeout)) {
2543 rc = FAILED;
2544 goto unlock;
2545 }
2546
2547 switch (session->tmf_state) {
2548 case TMF_SUCCESS:
2549 break;
2550 case TMF_TIMEDOUT:
2551 spin_unlock_bh(&session->frwd_lock);
2552 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2553 goto done;
2554 default:
2555 session->tmf_state = TMF_INITIAL;
2556 goto unlock;
2557 }
2558
2559 rc = SUCCESS;
2560 spin_unlock_bh(&session->frwd_lock);
2561
2562 iscsi_suspend_tx(conn);
2563
2564 spin_lock_bh(&session->frwd_lock);
2565 memset(hdr, 0, sizeof(*hdr));
2566 fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2567 session->tmf_state = TMF_INITIAL;
2568 spin_unlock_bh(&session->frwd_lock);
2569
2570 iscsi_start_tx(conn);
2571 goto done;
2572
2573unlock:
2574 spin_unlock_bh(&session->frwd_lock);
2575done:
2576 ISCSI_DBG_EH(session, "dev reset result = %s\n",
2577 rc == SUCCESS ? "SUCCESS" : "FAILED");
2578 mutex_unlock(&session->eh_mutex);
2579 return rc;
2580}
2581EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2582
2583void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2584{
2585 struct iscsi_session *session = cls_session->dd_data;
2586
2587 spin_lock_bh(&session->frwd_lock);
2588 if (session->state != ISCSI_STATE_LOGGED_IN) {
2589 session->state = ISCSI_STATE_RECOVERY_FAILED;
2590 wake_up(&session->ehwait);
2591 }
2592 spin_unlock_bh(&session->frwd_lock);
2593}
2594EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2595
2596/**
2597 * iscsi_eh_session_reset - drop session and attempt relogin
2598 * @sc: scsi command
2599 *
2600 * This function will wait for a relogin, session termination from
2601 * userspace, or a recovery/replacement timeout.
2602 */
2603int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2604{
2605 struct iscsi_cls_session *cls_session;
2606 struct iscsi_session *session;
2607 struct iscsi_conn *conn;
2608
2609 cls_session = starget_to_session(scsi_target(sc->device));
2610 session = cls_session->dd_data;
2611
2612 mutex_lock(&session->eh_mutex);
2613 spin_lock_bh(&session->frwd_lock);
2614 if (session->state == ISCSI_STATE_TERMINATE) {
2615failed:
2616 ISCSI_DBG_EH(session,
2617 "failing session reset: Could not log back into "
2618 "%s [age %d]\n", session->targetname,
2619 session->age);
2620 spin_unlock_bh(&session->frwd_lock);
2621 mutex_unlock(&session->eh_mutex);
2622 return FAILED;
2623 }
2624
2625 conn = session->leadconn;
2626 iscsi_get_conn(conn->cls_conn);
2627
2628 spin_unlock_bh(&session->frwd_lock);
2629 mutex_unlock(&session->eh_mutex);
2630
2631 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2632 iscsi_put_conn(conn->cls_conn);
2633
2634 ISCSI_DBG_EH(session, "wait for relogin\n");
2635 wait_event_interruptible(session->ehwait,
2636 session->state == ISCSI_STATE_TERMINATE ||
2637 session->state == ISCSI_STATE_LOGGED_IN ||
2638 session->state == ISCSI_STATE_RECOVERY_FAILED);
2639 if (signal_pending(current))
2640 flush_signals(current);
2641
2642 mutex_lock(&session->eh_mutex);
2643 spin_lock_bh(&session->frwd_lock);
2644 if (session->state == ISCSI_STATE_LOGGED_IN) {
2645 ISCSI_DBG_EH(session,
2646 "session reset succeeded for %s,%s\n",
2647 session->targetname, conn->persistent_address);
2648 } else
2649 goto failed;
2650 spin_unlock_bh(&session->frwd_lock);
2651 mutex_unlock(&session->eh_mutex);
2652 return SUCCESS;
2653}
2654EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2655
2656static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2657{
2658 memset(hdr, 0, sizeof(*hdr));
2659 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2660 hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2661 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2662 hdr->rtt = RESERVED_ITT;
2663}
2664
2665/**
2666 * iscsi_eh_target_reset - reset target
2667 * @sc: scsi command
2668 *
2669 * This will attempt to send a warm target reset.
2670 */
2671static int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2672{
2673 struct iscsi_cls_session *cls_session;
2674 struct iscsi_session *session;
2675 struct iscsi_conn *conn;
2676 struct iscsi_tm *hdr;
2677 int rc = FAILED;
2678
2679 cls_session = starget_to_session(scsi_target(sc->device));
2680 session = cls_session->dd_data;
2681
2682 ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2683 session->targetname);
2684
2685 mutex_lock(&session->eh_mutex);
2686 spin_lock_bh(&session->frwd_lock);
2687 /*
2688 * Just check if we are not logged in. We cannot check for
2689 * the phase because the reset could come from a ioctl.
2690 */
2691 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2692 goto unlock;
2693 conn = session->leadconn;
2694
2695 /* only have one tmf outstanding at a time */
2696 if (session->tmf_state != TMF_INITIAL)
2697 goto unlock;
2698 session->tmf_state = TMF_QUEUED;
2699
2700 hdr = &session->tmhdr;
2701 iscsi_prep_tgt_reset_pdu(sc, hdr);
2702
2703 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2704 session->tgt_reset_timeout)) {
2705 rc = FAILED;
2706 goto unlock;
2707 }
2708
2709 switch (session->tmf_state) {
2710 case TMF_SUCCESS:
2711 break;
2712 case TMF_TIMEDOUT:
2713 spin_unlock_bh(&session->frwd_lock);
2714 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2715 goto done;
2716 default:
2717 session->tmf_state = TMF_INITIAL;
2718 goto unlock;
2719 }
2720
2721 rc = SUCCESS;
2722 spin_unlock_bh(&session->frwd_lock);
2723
2724 iscsi_suspend_tx(conn);
2725
2726 spin_lock_bh(&session->frwd_lock);
2727 memset(hdr, 0, sizeof(*hdr));
2728 fail_scsi_tasks(conn, -1, DID_ERROR);
2729 session->tmf_state = TMF_INITIAL;
2730 spin_unlock_bh(&session->frwd_lock);
2731
2732 iscsi_start_tx(conn);
2733 goto done;
2734
2735unlock:
2736 spin_unlock_bh(&session->frwd_lock);
2737done:
2738 ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2739 rc == SUCCESS ? "SUCCESS" : "FAILED");
2740 mutex_unlock(&session->eh_mutex);
2741 return rc;
2742}
2743
2744/**
2745 * iscsi_eh_recover_target - reset target and possibly the session
2746 * @sc: scsi command
2747 *
2748 * This will attempt to send a warm target reset. If that fails,
2749 * we will escalate to ERL0 session recovery.
2750 */
2751int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2752{
2753 int rc;
2754
2755 rc = iscsi_eh_target_reset(sc);
2756 if (rc == FAILED)
2757 rc = iscsi_eh_session_reset(sc);
2758 return rc;
2759}
2760EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2761
2762/*
2763 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2764 * should be accessed via kfifo_{get,put} on q->queue.
2765 * Optionally, the caller can obtain the array of object pointers
2766 * by passing in a non-NULL @items pointer
2767 */
2768int
2769iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2770{
2771 int i, num_arrays = 1;
2772
2773 memset(q, 0, sizeof(*q));
2774
2775 q->max = max;
2776
2777 /* If the user passed an items pointer, he wants a copy of
2778 * the array. */
2779 if (items)
2780 num_arrays++;
2781 q->pool = kvcalloc(num_arrays * max, sizeof(void *), GFP_KERNEL);
2782 if (q->pool == NULL)
2783 return -ENOMEM;
2784
2785 kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2786
2787 for (i = 0; i < max; i++) {
2788 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2789 if (q->pool[i] == NULL) {
2790 q->max = i;
2791 goto enomem;
2792 }
2793 kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2794 }
2795
2796 if (items) {
2797 *items = q->pool + max;
2798 memcpy(*items, q->pool, max * sizeof(void *));
2799 }
2800
2801 return 0;
2802
2803enomem:
2804 iscsi_pool_free(q);
2805 return -ENOMEM;
2806}
2807EXPORT_SYMBOL_GPL(iscsi_pool_init);
2808
2809void iscsi_pool_free(struct iscsi_pool *q)
2810{
2811 int i;
2812
2813 for (i = 0; i < q->max; i++)
2814 kfree(q->pool[i]);
2815 kvfree(q->pool);
2816}
2817EXPORT_SYMBOL_GPL(iscsi_pool_free);
2818
2819int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost,
2820 uint16_t requested_cmds_max)
2821{
2822 int scsi_cmds, total_cmds = requested_cmds_max;
2823
2824check:
2825 if (!total_cmds)
2826 total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2827 /*
2828 * The iscsi layer needs some tasks for nop handling and tmfs,
2829 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2830 * + 1 command for scsi IO.
2831 */
2832 if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2833 printk(KERN_ERR "iscsi: invalid max cmds of %d. Must be a power of two that is at least %d.\n",
2834 total_cmds, ISCSI_TOTAL_CMDS_MIN);
2835 return -EINVAL;
2836 }
2837
2838 if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2839 printk(KERN_INFO "iscsi: invalid max cmds of %d. Must be a power of 2 less than or equal to %d. Using %d.\n",
2840 requested_cmds_max, ISCSI_TOTAL_CMDS_MAX,
2841 ISCSI_TOTAL_CMDS_MAX);
2842 total_cmds = ISCSI_TOTAL_CMDS_MAX;
2843 }
2844
2845 if (!is_power_of_2(total_cmds)) {
2846 total_cmds = rounddown_pow_of_two(total_cmds);
2847 if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2848 printk(KERN_ERR "iscsi: invalid max cmds of %d. Must be a power of 2 greater than %d.\n", requested_cmds_max, ISCSI_TOTAL_CMDS_MIN);
2849 return -EINVAL;
2850 }
2851
2852 printk(KERN_INFO "iscsi: invalid max cmds %d. Must be a power of 2. Rounding max cmds down to %d.\n",
2853 requested_cmds_max, total_cmds);
2854 }
2855
2856 scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2857 if (shost->can_queue && scsi_cmds > shost->can_queue) {
2858 total_cmds = shost->can_queue;
2859
2860 printk(KERN_INFO "iscsi: requested max cmds %u is higher than driver limit. Using driver limit %u\n",
2861 requested_cmds_max, shost->can_queue);
2862 goto check;
2863 }
2864
2865 return scsi_cmds;
2866}
2867EXPORT_SYMBOL_GPL(iscsi_host_get_max_scsi_cmds);
2868
2869/**
2870 * iscsi_host_add - add host to system
2871 * @shost: scsi host
2872 * @pdev: parent device
2873 *
2874 * This should be called by partial offload and software iscsi drivers
2875 * to add a host to the system.
2876 */
2877int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2878{
2879 if (!shost->can_queue)
2880 shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2881
2882 if (!shost->cmd_per_lun)
2883 shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2884
2885 return scsi_add_host(shost, pdev);
2886}
2887EXPORT_SYMBOL_GPL(iscsi_host_add);
2888
2889/**
2890 * iscsi_host_alloc - allocate a host and driver data
2891 * @sht: scsi host template
2892 * @dd_data_size: driver host data size
2893 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2894 *
2895 * This should be called by partial offload and software iscsi drivers.
2896 * To access the driver specific memory use the iscsi_host_priv() macro.
2897 */
2898struct Scsi_Host *iscsi_host_alloc(const struct scsi_host_template *sht,
2899 int dd_data_size, bool xmit_can_sleep)
2900{
2901 struct Scsi_Host *shost;
2902 struct iscsi_host *ihost;
2903
2904 shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2905 if (!shost)
2906 return NULL;
2907 ihost = shost_priv(shost);
2908
2909 if (xmit_can_sleep) {
2910 ihost->workq = alloc_workqueue("iscsi_q_%d",
2911 WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND,
2912 1, shost->host_no);
2913 if (!ihost->workq)
2914 goto free_host;
2915 }
2916
2917 spin_lock_init(&ihost->lock);
2918 ihost->state = ISCSI_HOST_SETUP;
2919 ihost->num_sessions = 0;
2920 init_waitqueue_head(&ihost->session_removal_wq);
2921 return shost;
2922
2923free_host:
2924 scsi_host_put(shost);
2925 return NULL;
2926}
2927EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2928
2929static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2930{
2931 iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2932}
2933
2934/**
2935 * iscsi_host_remove - remove host and sessions
2936 * @shost: scsi host
2937 * @is_shutdown: true if called from a driver shutdown callout
2938 *
2939 * If there are any sessions left, this will initiate the removal and wait
2940 * for the completion.
2941 */
2942void iscsi_host_remove(struct Scsi_Host *shost, bool is_shutdown)
2943{
2944 struct iscsi_host *ihost = shost_priv(shost);
2945 unsigned long flags;
2946
2947 spin_lock_irqsave(&ihost->lock, flags);
2948 ihost->state = ISCSI_HOST_REMOVED;
2949 spin_unlock_irqrestore(&ihost->lock, flags);
2950
2951 if (!is_shutdown)
2952 iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2953 else
2954 iscsi_host_for_each_session(shost, iscsi_force_destroy_session);
2955
2956 wait_event_interruptible(ihost->session_removal_wq,
2957 ihost->num_sessions == 0);
2958 if (signal_pending(current))
2959 flush_signals(current);
2960
2961 scsi_remove_host(shost);
2962}
2963EXPORT_SYMBOL_GPL(iscsi_host_remove);
2964
2965void iscsi_host_free(struct Scsi_Host *shost)
2966{
2967 struct iscsi_host *ihost = shost_priv(shost);
2968
2969 if (ihost->workq)
2970 destroy_workqueue(ihost->workq);
2971
2972 kfree(ihost->netdev);
2973 kfree(ihost->hwaddress);
2974 kfree(ihost->initiatorname);
2975 scsi_host_put(shost);
2976}
2977EXPORT_SYMBOL_GPL(iscsi_host_free);
2978
2979static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2980{
2981 struct iscsi_host *ihost = shost_priv(shost);
2982 unsigned long flags;
2983
2984 shost = scsi_host_get(shost);
2985 if (!shost) {
2986 printk(KERN_ERR "Invalid state. Cannot notify host removal "
2987 "of session teardown event because host already "
2988 "removed.\n");
2989 return;
2990 }
2991
2992 spin_lock_irqsave(&ihost->lock, flags);
2993 ihost->num_sessions--;
2994 if (ihost->num_sessions == 0)
2995 wake_up(&ihost->session_removal_wq);
2996 spin_unlock_irqrestore(&ihost->lock, flags);
2997 scsi_host_put(shost);
2998}
2999
3000/**
3001 * iscsi_session_setup - create iscsi cls session and host and session
3002 * @iscsit: iscsi transport template
3003 * @shost: scsi host
3004 * @cmds_max: session can queue
3005 * @dd_size: private driver data size, added to session allocation size
3006 * @cmd_task_size: LLD task private data size
3007 * @initial_cmdsn: initial CmdSN
3008 * @id: target ID to add to this session
3009 *
3010 * This can be used by software iscsi_transports that allocate
3011 * a session per scsi host.
3012 *
3013 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
3014 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
3015 * for nop handling and login/logout requests.
3016 */
3017struct iscsi_cls_session *
3018iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
3019 uint16_t cmds_max, int dd_size, int cmd_task_size,
3020 uint32_t initial_cmdsn, unsigned int id)
3021{
3022 struct iscsi_host *ihost = shost_priv(shost);
3023 struct iscsi_session *session;
3024 struct iscsi_cls_session *cls_session;
3025 int cmd_i, scsi_cmds;
3026 unsigned long flags;
3027
3028 spin_lock_irqsave(&ihost->lock, flags);
3029 if (ihost->state == ISCSI_HOST_REMOVED) {
3030 spin_unlock_irqrestore(&ihost->lock, flags);
3031 return NULL;
3032 }
3033 ihost->num_sessions++;
3034 spin_unlock_irqrestore(&ihost->lock, flags);
3035
3036 scsi_cmds = iscsi_host_get_max_scsi_cmds(shost, cmds_max);
3037 if (scsi_cmds < 0)
3038 goto dec_session_count;
3039
3040 cls_session = iscsi_alloc_session(shost, iscsit,
3041 sizeof(struct iscsi_session) +
3042 dd_size);
3043 if (!cls_session)
3044 goto dec_session_count;
3045 session = cls_session->dd_data;
3046 session->cls_session = cls_session;
3047 session->host = shost;
3048 session->state = ISCSI_STATE_FREE;
3049 session->fast_abort = 1;
3050 session->tgt_reset_timeout = 30;
3051 session->lu_reset_timeout = 15;
3052 session->abort_timeout = 10;
3053 session->scsi_cmds_max = scsi_cmds;
3054 session->cmds_max = scsi_cmds + ISCSI_MGMT_CMDS_MAX;
3055 session->queued_cmdsn = session->cmdsn = initial_cmdsn;
3056 session->exp_cmdsn = initial_cmdsn + 1;
3057 session->max_cmdsn = initial_cmdsn + 1;
3058 session->max_r2t = 1;
3059 session->tt = iscsit;
3060 session->dd_data = cls_session->dd_data + sizeof(*session);
3061
3062 session->tmf_state = TMF_INITIAL;
3063 timer_setup(&session->tmf_timer, iscsi_tmf_timedout, 0);
3064 mutex_init(&session->eh_mutex);
3065 init_waitqueue_head(&session->ehwait);
3066
3067 spin_lock_init(&session->frwd_lock);
3068 spin_lock_init(&session->back_lock);
3069
3070 /* initialize SCSI PDU commands pool */
3071 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
3072 (void***)&session->cmds,
3073 cmd_task_size + sizeof(struct iscsi_task)))
3074 goto cmdpool_alloc_fail;
3075
3076 /* pre-format cmds pool with ITT */
3077 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
3078 struct iscsi_task *task = session->cmds[cmd_i];
3079
3080 if (cmd_task_size)
3081 task->dd_data = &task[1];
3082 task->itt = cmd_i;
3083 task->state = ISCSI_TASK_FREE;
3084 INIT_LIST_HEAD(&task->running);
3085 }
3086
3087 if (!try_module_get(iscsit->owner))
3088 goto module_get_fail;
3089
3090 if (iscsi_add_session(cls_session, id))
3091 goto cls_session_fail;
3092
3093 return cls_session;
3094
3095cls_session_fail:
3096 module_put(iscsit->owner);
3097module_get_fail:
3098 iscsi_pool_free(&session->cmdpool);
3099cmdpool_alloc_fail:
3100 iscsi_free_session(cls_session);
3101dec_session_count:
3102 iscsi_host_dec_session_cnt(shost);
3103 return NULL;
3104}
3105EXPORT_SYMBOL_GPL(iscsi_session_setup);
3106
3107/*
3108 * issi_session_remove - Remove session from iSCSI class.
3109 */
3110void iscsi_session_remove(struct iscsi_cls_session *cls_session)
3111{
3112 struct iscsi_session *session = cls_session->dd_data;
3113 struct Scsi_Host *shost = session->host;
3114
3115 iscsi_remove_session(cls_session);
3116 /*
3117 * host removal only has to wait for its children to be removed from
3118 * sysfs, and iscsi_tcp needs to do iscsi_host_remove before freeing
3119 * the session, so drop the session count here.
3120 */
3121 iscsi_host_dec_session_cnt(shost);
3122}
3123EXPORT_SYMBOL_GPL(iscsi_session_remove);
3124
3125/**
3126 * iscsi_session_free - Free iscsi session and it's resources
3127 * @cls_session: iscsi session
3128 */
3129void iscsi_session_free(struct iscsi_cls_session *cls_session)
3130{
3131 struct iscsi_session *session = cls_session->dd_data;
3132 struct module *owner = cls_session->transport->owner;
3133
3134 iscsi_pool_free(&session->cmdpool);
3135 kfree(session->password);
3136 kfree(session->password_in);
3137 kfree(session->username);
3138 kfree(session->username_in);
3139 kfree(session->targetname);
3140 kfree(session->targetalias);
3141 kfree(session->initiatorname);
3142 kfree(session->boot_root);
3143 kfree(session->boot_nic);
3144 kfree(session->boot_target);
3145 kfree(session->ifacename);
3146 kfree(session->portal_type);
3147 kfree(session->discovery_parent_type);
3148
3149 iscsi_free_session(cls_session);
3150 module_put(owner);
3151}
3152EXPORT_SYMBOL_GPL(iscsi_session_free);
3153
3154/**
3155 * iscsi_session_teardown - destroy session and cls_session
3156 * @cls_session: iscsi session
3157 */
3158void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
3159{
3160 iscsi_session_remove(cls_session);
3161 iscsi_session_free(cls_session);
3162}
3163EXPORT_SYMBOL_GPL(iscsi_session_teardown);
3164
3165/**
3166 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
3167 * @cls_session: iscsi_cls_session
3168 * @dd_size: private driver data size
3169 * @conn_idx: cid
3170 */
3171struct iscsi_cls_conn *
3172iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
3173 uint32_t conn_idx)
3174{
3175 struct iscsi_session *session = cls_session->dd_data;
3176 struct iscsi_conn *conn;
3177 struct iscsi_cls_conn *cls_conn;
3178 char *data;
3179 int err;
3180
3181 cls_conn = iscsi_alloc_conn(cls_session, sizeof(*conn) + dd_size,
3182 conn_idx);
3183 if (!cls_conn)
3184 return NULL;
3185 conn = cls_conn->dd_data;
3186
3187 conn->dd_data = cls_conn->dd_data + sizeof(*conn);
3188 conn->session = session;
3189 conn->cls_conn = cls_conn;
3190 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
3191 conn->id = conn_idx;
3192 conn->exp_statsn = 0;
3193
3194 timer_setup(&conn->transport_timer, iscsi_check_transport_timeouts, 0);
3195
3196 INIT_LIST_HEAD(&conn->mgmtqueue);
3197 INIT_LIST_HEAD(&conn->cmdqueue);
3198 INIT_LIST_HEAD(&conn->requeue);
3199 INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
3200
3201 /* allocate login_task used for the login/text sequences */
3202 spin_lock_bh(&session->frwd_lock);
3203 if (!kfifo_out(&session->cmdpool.queue,
3204 (void*)&conn->login_task,
3205 sizeof(void*))) {
3206 spin_unlock_bh(&session->frwd_lock);
3207 goto login_task_alloc_fail;
3208 }
3209 spin_unlock_bh(&session->frwd_lock);
3210
3211 data = (char *) __get_free_pages(GFP_KERNEL,
3212 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
3213 if (!data)
3214 goto login_task_data_alloc_fail;
3215 conn->login_task->data = conn->data = data;
3216
3217 err = iscsi_add_conn(cls_conn);
3218 if (err)
3219 goto login_task_add_dev_fail;
3220
3221 return cls_conn;
3222
3223login_task_add_dev_fail:
3224 free_pages((unsigned long) conn->data,
3225 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
3226
3227login_task_data_alloc_fail:
3228 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
3229 sizeof(void*));
3230login_task_alloc_fail:
3231 iscsi_put_conn(cls_conn);
3232 return NULL;
3233}
3234EXPORT_SYMBOL_GPL(iscsi_conn_setup);
3235
3236/**
3237 * iscsi_conn_teardown - teardown iscsi connection
3238 * @cls_conn: iscsi class connection
3239 *
3240 * TODO: we may need to make this into a two step process
3241 * like scsi-mls remove + put host
3242 */
3243void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
3244{
3245 struct iscsi_conn *conn = cls_conn->dd_data;
3246 struct iscsi_session *session = conn->session;
3247
3248 iscsi_remove_conn(cls_conn);
3249
3250 del_timer_sync(&conn->transport_timer);
3251
3252 mutex_lock(&session->eh_mutex);
3253 spin_lock_bh(&session->frwd_lock);
3254 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
3255 if (session->leadconn == conn) {
3256 /*
3257 * leading connection? then give up on recovery.
3258 */
3259 session->state = ISCSI_STATE_TERMINATE;
3260 wake_up(&session->ehwait);
3261 }
3262 spin_unlock_bh(&session->frwd_lock);
3263
3264 /* flush queued up work because we free the connection below */
3265 iscsi_suspend_tx(conn);
3266
3267 spin_lock_bh(&session->frwd_lock);
3268 free_pages((unsigned long) conn->data,
3269 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
3270 kfree(conn->persistent_address);
3271 kfree(conn->local_ipaddr);
3272 /* regular RX path uses back_lock */
3273 spin_lock_bh(&session->back_lock);
3274 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
3275 sizeof(void*));
3276 spin_unlock_bh(&session->back_lock);
3277 if (session->leadconn == conn)
3278 session->leadconn = NULL;
3279 spin_unlock_bh(&session->frwd_lock);
3280 mutex_unlock(&session->eh_mutex);
3281
3282 iscsi_put_conn(cls_conn);
3283}
3284EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
3285
3286int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
3287{
3288 struct iscsi_conn *conn = cls_conn->dd_data;
3289 struct iscsi_session *session = conn->session;
3290
3291 if (!session) {
3292 iscsi_conn_printk(KERN_ERR, conn,
3293 "can't start unbound connection\n");
3294 return -EPERM;
3295 }
3296
3297 if ((session->imm_data_en || !session->initial_r2t_en) &&
3298 session->first_burst > session->max_burst) {
3299 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
3300 "first_burst %d max_burst %d\n",
3301 session->first_burst, session->max_burst);
3302 return -EINVAL;
3303 }
3304
3305 if (conn->ping_timeout && !conn->recv_timeout) {
3306 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
3307 "zero. Using 5 seconds\n.");
3308 conn->recv_timeout = 5;
3309 }
3310
3311 if (conn->recv_timeout && !conn->ping_timeout) {
3312 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
3313 "zero. Using 5 seconds.\n");
3314 conn->ping_timeout = 5;
3315 }
3316
3317 spin_lock_bh(&session->frwd_lock);
3318 conn->c_stage = ISCSI_CONN_STARTED;
3319 session->state = ISCSI_STATE_LOGGED_IN;
3320 session->queued_cmdsn = session->cmdsn;
3321
3322 conn->last_recv = jiffies;
3323 conn->last_ping = jiffies;
3324 if (conn->recv_timeout && conn->ping_timeout)
3325 mod_timer(&conn->transport_timer,
3326 jiffies + (conn->recv_timeout * HZ));
3327
3328 switch(conn->stop_stage) {
3329 case STOP_CONN_RECOVER:
3330 /*
3331 * unblock eh_abort() if it is blocked. re-try all
3332 * commands after successful recovery
3333 */
3334 conn->stop_stage = 0;
3335 session->tmf_state = TMF_INITIAL;
3336 session->age++;
3337 if (session->age == 16)
3338 session->age = 0;
3339 break;
3340 case STOP_CONN_TERM:
3341 conn->stop_stage = 0;
3342 break;
3343 default:
3344 break;
3345 }
3346 spin_unlock_bh(&session->frwd_lock);
3347
3348 iscsi_unblock_session(session->cls_session);
3349 wake_up(&session->ehwait);
3350 return 0;
3351}
3352EXPORT_SYMBOL_GPL(iscsi_conn_start);
3353
3354static void
3355fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3356{
3357 struct iscsi_task *task;
3358 int i, state;
3359
3360 for (i = 0; i < conn->session->cmds_max; i++) {
3361 task = conn->session->cmds[i];
3362 if (task->sc)
3363 continue;
3364
3365 if (task->state == ISCSI_TASK_FREE)
3366 continue;
3367
3368 ISCSI_DBG_SESSION(conn->session,
3369 "failing mgmt itt 0x%x state %d\n",
3370 task->itt, task->state);
3371
3372 spin_lock_bh(&session->back_lock);
3373 if (cleanup_queued_task(task)) {
3374 spin_unlock_bh(&session->back_lock);
3375 continue;
3376 }
3377
3378 state = ISCSI_TASK_ABRT_SESS_RECOV;
3379 if (task->state == ISCSI_TASK_PENDING)
3380 state = ISCSI_TASK_COMPLETED;
3381 iscsi_complete_task(task, state);
3382 spin_unlock_bh(&session->back_lock);
3383 }
3384}
3385
3386void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3387{
3388 struct iscsi_conn *conn = cls_conn->dd_data;
3389 struct iscsi_session *session = conn->session;
3390 int old_stop_stage;
3391
3392 mutex_lock(&session->eh_mutex);
3393 spin_lock_bh(&session->frwd_lock);
3394 if (conn->stop_stage == STOP_CONN_TERM) {
3395 spin_unlock_bh(&session->frwd_lock);
3396 mutex_unlock(&session->eh_mutex);
3397 return;
3398 }
3399
3400 /*
3401 * When this is called for the in_login state, we only want to clean
3402 * up the login task and connection. We do not need to block and set
3403 * the recovery state again
3404 */
3405 if (flag == STOP_CONN_TERM)
3406 session->state = ISCSI_STATE_TERMINATE;
3407 else if (conn->stop_stage != STOP_CONN_RECOVER)
3408 session->state = ISCSI_STATE_IN_RECOVERY;
3409
3410 old_stop_stage = conn->stop_stage;
3411 conn->stop_stage = flag;
3412 spin_unlock_bh(&session->frwd_lock);
3413
3414 del_timer_sync(&conn->transport_timer);
3415 iscsi_suspend_tx(conn);
3416
3417 spin_lock_bh(&session->frwd_lock);
3418 conn->c_stage = ISCSI_CONN_STOPPED;
3419 spin_unlock_bh(&session->frwd_lock);
3420
3421 /*
3422 * for connection level recovery we should not calculate
3423 * header digest. conn->hdr_size used for optimization
3424 * in hdr_extract() and will be re-negotiated at
3425 * set_param() time.
3426 */
3427 if (flag == STOP_CONN_RECOVER) {
3428 conn->hdrdgst_en = 0;
3429 conn->datadgst_en = 0;
3430 if (session->state == ISCSI_STATE_IN_RECOVERY &&
3431 old_stop_stage != STOP_CONN_RECOVER) {
3432 ISCSI_DBG_SESSION(session, "blocking session\n");
3433 iscsi_block_session(session->cls_session);
3434 }
3435 }
3436
3437 /*
3438 * flush queues.
3439 */
3440 spin_lock_bh(&session->frwd_lock);
3441 fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3442 fail_mgmt_tasks(session, conn);
3443 memset(&session->tmhdr, 0, sizeof(session->tmhdr));
3444 spin_unlock_bh(&session->frwd_lock);
3445 mutex_unlock(&session->eh_mutex);
3446}
3447EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3448
3449int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3450 struct iscsi_cls_conn *cls_conn, int is_leading)
3451{
3452 struct iscsi_session *session = cls_session->dd_data;
3453 struct iscsi_conn *conn = cls_conn->dd_data;
3454
3455 spin_lock_bh(&session->frwd_lock);
3456 if (is_leading)
3457 session->leadconn = conn;
3458
3459 set_bit(ISCSI_CONN_FLAG_BOUND, &conn->flags);
3460 spin_unlock_bh(&session->frwd_lock);
3461
3462 /*
3463 * The target could have reduced it's window size between logins, so
3464 * we have to reset max/exp cmdsn so we can see the new values.
3465 */
3466 spin_lock_bh(&session->back_lock);
3467 session->max_cmdsn = session->exp_cmdsn = session->cmdsn + 1;
3468 spin_unlock_bh(&session->back_lock);
3469 /*
3470 * Unblock xmitworker(), Login Phase will pass through.
3471 */
3472 clear_bit(ISCSI_CONN_FLAG_SUSPEND_RX, &conn->flags);
3473 clear_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags);
3474 return 0;
3475}
3476EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3477
3478int iscsi_switch_str_param(char **param, char *new_val_buf)
3479{
3480 char *new_val;
3481
3482 if (*param) {
3483 if (!strcmp(*param, new_val_buf))
3484 return 0;
3485 }
3486
3487 new_val = kstrdup(new_val_buf, GFP_NOIO);
3488 if (!new_val)
3489 return -ENOMEM;
3490
3491 kfree(*param);
3492 *param = new_val;
3493 return 0;
3494}
3495EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3496
3497int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3498 enum iscsi_param param, char *buf, int buflen)
3499{
3500 struct iscsi_conn *conn = cls_conn->dd_data;
3501 struct iscsi_session *session = conn->session;
3502 int val;
3503
3504 switch(param) {
3505 case ISCSI_PARAM_FAST_ABORT:
3506 sscanf(buf, "%d", &session->fast_abort);
3507 break;
3508 case ISCSI_PARAM_ABORT_TMO:
3509 sscanf(buf, "%d", &session->abort_timeout);
3510 break;
3511 case ISCSI_PARAM_LU_RESET_TMO:
3512 sscanf(buf, "%d", &session->lu_reset_timeout);
3513 break;
3514 case ISCSI_PARAM_TGT_RESET_TMO:
3515 sscanf(buf, "%d", &session->tgt_reset_timeout);
3516 break;
3517 case ISCSI_PARAM_PING_TMO:
3518 sscanf(buf, "%d", &conn->ping_timeout);
3519 break;
3520 case ISCSI_PARAM_RECV_TMO:
3521 sscanf(buf, "%d", &conn->recv_timeout);
3522 break;
3523 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3524 sscanf(buf, "%d", &conn->max_recv_dlength);
3525 break;
3526 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3527 sscanf(buf, "%d", &conn->max_xmit_dlength);
3528 break;
3529 case ISCSI_PARAM_HDRDGST_EN:
3530 sscanf(buf, "%d", &conn->hdrdgst_en);
3531 break;
3532 case ISCSI_PARAM_DATADGST_EN:
3533 sscanf(buf, "%d", &conn->datadgst_en);
3534 break;
3535 case ISCSI_PARAM_INITIAL_R2T_EN:
3536 sscanf(buf, "%d", &session->initial_r2t_en);
3537 break;
3538 case ISCSI_PARAM_MAX_R2T:
3539 sscanf(buf, "%hu", &session->max_r2t);
3540 break;
3541 case ISCSI_PARAM_IMM_DATA_EN:
3542 sscanf(buf, "%d", &session->imm_data_en);
3543 break;
3544 case ISCSI_PARAM_FIRST_BURST:
3545 sscanf(buf, "%d", &session->first_burst);
3546 break;
3547 case ISCSI_PARAM_MAX_BURST:
3548 sscanf(buf, "%d", &session->max_burst);
3549 break;
3550 case ISCSI_PARAM_PDU_INORDER_EN:
3551 sscanf(buf, "%d", &session->pdu_inorder_en);
3552 break;
3553 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3554 sscanf(buf, "%d", &session->dataseq_inorder_en);
3555 break;
3556 case ISCSI_PARAM_ERL:
3557 sscanf(buf, "%d", &session->erl);
3558 break;
3559 case ISCSI_PARAM_EXP_STATSN:
3560 sscanf(buf, "%u", &conn->exp_statsn);
3561 break;
3562 case ISCSI_PARAM_USERNAME:
3563 return iscsi_switch_str_param(&session->username, buf);
3564 case ISCSI_PARAM_USERNAME_IN:
3565 return iscsi_switch_str_param(&session->username_in, buf);
3566 case ISCSI_PARAM_PASSWORD:
3567 return iscsi_switch_str_param(&session->password, buf);
3568 case ISCSI_PARAM_PASSWORD_IN:
3569 return iscsi_switch_str_param(&session->password_in, buf);
3570 case ISCSI_PARAM_TARGET_NAME:
3571 return iscsi_switch_str_param(&session->targetname, buf);
3572 case ISCSI_PARAM_TARGET_ALIAS:
3573 return iscsi_switch_str_param(&session->targetalias, buf);
3574 case ISCSI_PARAM_TPGT:
3575 sscanf(buf, "%d", &session->tpgt);
3576 break;
3577 case ISCSI_PARAM_PERSISTENT_PORT:
3578 sscanf(buf, "%d", &conn->persistent_port);
3579 break;
3580 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3581 return iscsi_switch_str_param(&conn->persistent_address, buf);
3582 case ISCSI_PARAM_IFACE_NAME:
3583 return iscsi_switch_str_param(&session->ifacename, buf);
3584 case ISCSI_PARAM_INITIATOR_NAME:
3585 return iscsi_switch_str_param(&session->initiatorname, buf);
3586 case ISCSI_PARAM_BOOT_ROOT:
3587 return iscsi_switch_str_param(&session->boot_root, buf);
3588 case ISCSI_PARAM_BOOT_NIC:
3589 return iscsi_switch_str_param(&session->boot_nic, buf);
3590 case ISCSI_PARAM_BOOT_TARGET:
3591 return iscsi_switch_str_param(&session->boot_target, buf);
3592 case ISCSI_PARAM_PORTAL_TYPE:
3593 return iscsi_switch_str_param(&session->portal_type, buf);
3594 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3595 return iscsi_switch_str_param(&session->discovery_parent_type,
3596 buf);
3597 case ISCSI_PARAM_DISCOVERY_SESS:
3598 sscanf(buf, "%d", &val);
3599 session->discovery_sess = !!val;
3600 break;
3601 case ISCSI_PARAM_LOCAL_IPADDR:
3602 return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3603 default:
3604 return -ENOSYS;
3605 }
3606
3607 return 0;
3608}
3609EXPORT_SYMBOL_GPL(iscsi_set_param);
3610
3611int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3612 enum iscsi_param param, char *buf)
3613{
3614 struct iscsi_session *session = cls_session->dd_data;
3615 int len;
3616
3617 switch(param) {
3618 case ISCSI_PARAM_FAST_ABORT:
3619 len = sysfs_emit(buf, "%d\n", session->fast_abort);
3620 break;
3621 case ISCSI_PARAM_ABORT_TMO:
3622 len = sysfs_emit(buf, "%d\n", session->abort_timeout);
3623 break;
3624 case ISCSI_PARAM_LU_RESET_TMO:
3625 len = sysfs_emit(buf, "%d\n", session->lu_reset_timeout);
3626 break;
3627 case ISCSI_PARAM_TGT_RESET_TMO:
3628 len = sysfs_emit(buf, "%d\n", session->tgt_reset_timeout);
3629 break;
3630 case ISCSI_PARAM_INITIAL_R2T_EN:
3631 len = sysfs_emit(buf, "%d\n", session->initial_r2t_en);
3632 break;
3633 case ISCSI_PARAM_MAX_R2T:
3634 len = sysfs_emit(buf, "%hu\n", session->max_r2t);
3635 break;
3636 case ISCSI_PARAM_IMM_DATA_EN:
3637 len = sysfs_emit(buf, "%d\n", session->imm_data_en);
3638 break;
3639 case ISCSI_PARAM_FIRST_BURST:
3640 len = sysfs_emit(buf, "%u\n", session->first_burst);
3641 break;
3642 case ISCSI_PARAM_MAX_BURST:
3643 len = sysfs_emit(buf, "%u\n", session->max_burst);
3644 break;
3645 case ISCSI_PARAM_PDU_INORDER_EN:
3646 len = sysfs_emit(buf, "%d\n", session->pdu_inorder_en);
3647 break;
3648 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3649 len = sysfs_emit(buf, "%d\n", session->dataseq_inorder_en);
3650 break;
3651 case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3652 len = sysfs_emit(buf, "%d\n", session->def_taskmgmt_tmo);
3653 break;
3654 case ISCSI_PARAM_ERL:
3655 len = sysfs_emit(buf, "%d\n", session->erl);
3656 break;
3657 case ISCSI_PARAM_TARGET_NAME:
3658 len = sysfs_emit(buf, "%s\n", session->targetname);
3659 break;
3660 case ISCSI_PARAM_TARGET_ALIAS:
3661 len = sysfs_emit(buf, "%s\n", session->targetalias);
3662 break;
3663 case ISCSI_PARAM_TPGT:
3664 len = sysfs_emit(buf, "%d\n", session->tpgt);
3665 break;
3666 case ISCSI_PARAM_USERNAME:
3667 len = sysfs_emit(buf, "%s\n", session->username);
3668 break;
3669 case ISCSI_PARAM_USERNAME_IN:
3670 len = sysfs_emit(buf, "%s\n", session->username_in);
3671 break;
3672 case ISCSI_PARAM_PASSWORD:
3673 len = sysfs_emit(buf, "%s\n", session->password);
3674 break;
3675 case ISCSI_PARAM_PASSWORD_IN:
3676 len = sysfs_emit(buf, "%s\n", session->password_in);
3677 break;
3678 case ISCSI_PARAM_IFACE_NAME:
3679 len = sysfs_emit(buf, "%s\n", session->ifacename);
3680 break;
3681 case ISCSI_PARAM_INITIATOR_NAME:
3682 len = sysfs_emit(buf, "%s\n", session->initiatorname);
3683 break;
3684 case ISCSI_PARAM_BOOT_ROOT:
3685 len = sysfs_emit(buf, "%s\n", session->boot_root);
3686 break;
3687 case ISCSI_PARAM_BOOT_NIC:
3688 len = sysfs_emit(buf, "%s\n", session->boot_nic);
3689 break;
3690 case ISCSI_PARAM_BOOT_TARGET:
3691 len = sysfs_emit(buf, "%s\n", session->boot_target);
3692 break;
3693 case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3694 len = sysfs_emit(buf, "%u\n", session->auto_snd_tgt_disable);
3695 break;
3696 case ISCSI_PARAM_DISCOVERY_SESS:
3697 len = sysfs_emit(buf, "%u\n", session->discovery_sess);
3698 break;
3699 case ISCSI_PARAM_PORTAL_TYPE:
3700 len = sysfs_emit(buf, "%s\n", session->portal_type);
3701 break;
3702 case ISCSI_PARAM_CHAP_AUTH_EN:
3703 len = sysfs_emit(buf, "%u\n", session->chap_auth_en);
3704 break;
3705 case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3706 len = sysfs_emit(buf, "%u\n", session->discovery_logout_en);
3707 break;
3708 case ISCSI_PARAM_BIDI_CHAP_EN:
3709 len = sysfs_emit(buf, "%u\n", session->bidi_chap_en);
3710 break;
3711 case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3712 len = sysfs_emit(buf, "%u\n", session->discovery_auth_optional);
3713 break;
3714 case ISCSI_PARAM_DEF_TIME2WAIT:
3715 len = sysfs_emit(buf, "%d\n", session->time2wait);
3716 break;
3717 case ISCSI_PARAM_DEF_TIME2RETAIN:
3718 len = sysfs_emit(buf, "%d\n", session->time2retain);
3719 break;
3720 case ISCSI_PARAM_TSID:
3721 len = sysfs_emit(buf, "%u\n", session->tsid);
3722 break;
3723 case ISCSI_PARAM_ISID:
3724 len = sysfs_emit(buf, "%02x%02x%02x%02x%02x%02x\n",
3725 session->isid[0], session->isid[1],
3726 session->isid[2], session->isid[3],
3727 session->isid[4], session->isid[5]);
3728 break;
3729 case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3730 len = sysfs_emit(buf, "%u\n", session->discovery_parent_idx);
3731 break;
3732 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3733 if (session->discovery_parent_type)
3734 len = sysfs_emit(buf, "%s\n",
3735 session->discovery_parent_type);
3736 else
3737 len = sysfs_emit(buf, "\n");
3738 break;
3739 default:
3740 return -ENOSYS;
3741 }
3742
3743 return len;
3744}
3745EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3746
3747int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3748 enum iscsi_param param, char *buf)
3749{
3750 struct sockaddr_in6 *sin6 = NULL;
3751 struct sockaddr_in *sin = NULL;
3752 int len;
3753
3754 switch (addr->ss_family) {
3755 case AF_INET:
3756 sin = (struct sockaddr_in *)addr;
3757 break;
3758 case AF_INET6:
3759 sin6 = (struct sockaddr_in6 *)addr;
3760 break;
3761 default:
3762 return -EINVAL;
3763 }
3764
3765 switch (param) {
3766 case ISCSI_PARAM_CONN_ADDRESS:
3767 case ISCSI_HOST_PARAM_IPADDRESS:
3768 if (sin)
3769 len = sysfs_emit(buf, "%pI4\n", &sin->sin_addr.s_addr);
3770 else
3771 len = sysfs_emit(buf, "%pI6\n", &sin6->sin6_addr);
3772 break;
3773 case ISCSI_PARAM_CONN_PORT:
3774 case ISCSI_PARAM_LOCAL_PORT:
3775 if (sin)
3776 len = sysfs_emit(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3777 else
3778 len = sysfs_emit(buf, "%hu\n",
3779 be16_to_cpu(sin6->sin6_port));
3780 break;
3781 default:
3782 return -EINVAL;
3783 }
3784
3785 return len;
3786}
3787EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3788
3789int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3790 enum iscsi_param param, char *buf)
3791{
3792 struct iscsi_conn *conn = cls_conn->dd_data;
3793 int len;
3794
3795 switch(param) {
3796 case ISCSI_PARAM_PING_TMO:
3797 len = sysfs_emit(buf, "%u\n", conn->ping_timeout);
3798 break;
3799 case ISCSI_PARAM_RECV_TMO:
3800 len = sysfs_emit(buf, "%u\n", conn->recv_timeout);
3801 break;
3802 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3803 len = sysfs_emit(buf, "%u\n", conn->max_recv_dlength);
3804 break;
3805 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3806 len = sysfs_emit(buf, "%u\n", conn->max_xmit_dlength);
3807 break;
3808 case ISCSI_PARAM_HDRDGST_EN:
3809 len = sysfs_emit(buf, "%d\n", conn->hdrdgst_en);
3810 break;
3811 case ISCSI_PARAM_DATADGST_EN:
3812 len = sysfs_emit(buf, "%d\n", conn->datadgst_en);
3813 break;
3814 case ISCSI_PARAM_IFMARKER_EN:
3815 len = sysfs_emit(buf, "%d\n", conn->ifmarker_en);
3816 break;
3817 case ISCSI_PARAM_OFMARKER_EN:
3818 len = sysfs_emit(buf, "%d\n", conn->ofmarker_en);
3819 break;
3820 case ISCSI_PARAM_EXP_STATSN:
3821 len = sysfs_emit(buf, "%u\n", conn->exp_statsn);
3822 break;
3823 case ISCSI_PARAM_PERSISTENT_PORT:
3824 len = sysfs_emit(buf, "%d\n", conn->persistent_port);
3825 break;
3826 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3827 len = sysfs_emit(buf, "%s\n", conn->persistent_address);
3828 break;
3829 case ISCSI_PARAM_STATSN:
3830 len = sysfs_emit(buf, "%u\n", conn->statsn);
3831 break;
3832 case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3833 len = sysfs_emit(buf, "%u\n", conn->max_segment_size);
3834 break;
3835 case ISCSI_PARAM_KEEPALIVE_TMO:
3836 len = sysfs_emit(buf, "%u\n", conn->keepalive_tmo);
3837 break;
3838 case ISCSI_PARAM_LOCAL_PORT:
3839 len = sysfs_emit(buf, "%u\n", conn->local_port);
3840 break;
3841 case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3842 len = sysfs_emit(buf, "%u\n", conn->tcp_timestamp_stat);
3843 break;
3844 case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3845 len = sysfs_emit(buf, "%u\n", conn->tcp_nagle_disable);
3846 break;
3847 case ISCSI_PARAM_TCP_WSF_DISABLE:
3848 len = sysfs_emit(buf, "%u\n", conn->tcp_wsf_disable);
3849 break;
3850 case ISCSI_PARAM_TCP_TIMER_SCALE:
3851 len = sysfs_emit(buf, "%u\n", conn->tcp_timer_scale);
3852 break;
3853 case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3854 len = sysfs_emit(buf, "%u\n", conn->tcp_timestamp_en);
3855 break;
3856 case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3857 len = sysfs_emit(buf, "%u\n", conn->fragment_disable);
3858 break;
3859 case ISCSI_PARAM_IPV4_TOS:
3860 len = sysfs_emit(buf, "%u\n", conn->ipv4_tos);
3861 break;
3862 case ISCSI_PARAM_IPV6_TC:
3863 len = sysfs_emit(buf, "%u\n", conn->ipv6_traffic_class);
3864 break;
3865 case ISCSI_PARAM_IPV6_FLOW_LABEL:
3866 len = sysfs_emit(buf, "%u\n", conn->ipv6_flow_label);
3867 break;
3868 case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3869 len = sysfs_emit(buf, "%u\n", conn->is_fw_assigned_ipv6);
3870 break;
3871 case ISCSI_PARAM_TCP_XMIT_WSF:
3872 len = sysfs_emit(buf, "%u\n", conn->tcp_xmit_wsf);
3873 break;
3874 case ISCSI_PARAM_TCP_RECV_WSF:
3875 len = sysfs_emit(buf, "%u\n", conn->tcp_recv_wsf);
3876 break;
3877 case ISCSI_PARAM_LOCAL_IPADDR:
3878 len = sysfs_emit(buf, "%s\n", conn->local_ipaddr);
3879 break;
3880 default:
3881 return -ENOSYS;
3882 }
3883
3884 return len;
3885}
3886EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3887
3888int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3889 char *buf)
3890{
3891 struct iscsi_host *ihost = shost_priv(shost);
3892 int len;
3893
3894 switch (param) {
3895 case ISCSI_HOST_PARAM_NETDEV_NAME:
3896 len = sysfs_emit(buf, "%s\n", ihost->netdev);
3897 break;
3898 case ISCSI_HOST_PARAM_HWADDRESS:
3899 len = sysfs_emit(buf, "%s\n", ihost->hwaddress);
3900 break;
3901 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3902 len = sysfs_emit(buf, "%s\n", ihost->initiatorname);
3903 break;
3904 default:
3905 return -ENOSYS;
3906 }
3907
3908 return len;
3909}
3910EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3911
3912int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3913 char *buf, int buflen)
3914{
3915 struct iscsi_host *ihost = shost_priv(shost);
3916
3917 switch (param) {
3918 case ISCSI_HOST_PARAM_NETDEV_NAME:
3919 return iscsi_switch_str_param(&ihost->netdev, buf);
3920 case ISCSI_HOST_PARAM_HWADDRESS:
3921 return iscsi_switch_str_param(&ihost->hwaddress, buf);
3922 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3923 return iscsi_switch_str_param(&ihost->initiatorname, buf);
3924 default:
3925 return -ENOSYS;
3926 }
3927
3928 return 0;
3929}
3930EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3931
3932MODULE_AUTHOR("Mike Christie");
3933MODULE_DESCRIPTION("iSCSI library functions");
3934MODULE_LICENSE("GPL");
1/*
2 * iSCSI lib functions
3 *
4 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
5 * Copyright (C) 2004 - 2006 Mike Christie
6 * Copyright (C) 2004 - 2005 Dmitry Yusupov
7 * Copyright (C) 2004 - 2005 Alex Aizman
8 * maintained by open-iscsi@googlegroups.com
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 */
24#include <linux/types.h>
25#include <linux/kfifo.h>
26#include <linux/delay.h>
27#include <linux/log2.h>
28#include <linux/slab.h>
29#include <linux/sched/signal.h>
30#include <linux/module.h>
31#include <asm/unaligned.h>
32#include <net/tcp.h>
33#include <scsi/scsi_cmnd.h>
34#include <scsi/scsi_device.h>
35#include <scsi/scsi_eh.h>
36#include <scsi/scsi_tcq.h>
37#include <scsi/scsi_host.h>
38#include <scsi/scsi.h>
39#include <scsi/iscsi_proto.h>
40#include <scsi/scsi_transport.h>
41#include <scsi/scsi_transport_iscsi.h>
42#include <scsi/libiscsi.h>
43
44static int iscsi_dbg_lib_conn;
45module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int,
46 S_IRUGO | S_IWUSR);
47MODULE_PARM_DESC(debug_libiscsi_conn,
48 "Turn on debugging for connections in libiscsi module. "
49 "Set to 1 to turn on, and zero to turn off. Default is off.");
50
51static int iscsi_dbg_lib_session;
52module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int,
53 S_IRUGO | S_IWUSR);
54MODULE_PARM_DESC(debug_libiscsi_session,
55 "Turn on debugging for sessions in libiscsi module. "
56 "Set to 1 to turn on, and zero to turn off. Default is off.");
57
58static int iscsi_dbg_lib_eh;
59module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int,
60 S_IRUGO | S_IWUSR);
61MODULE_PARM_DESC(debug_libiscsi_eh,
62 "Turn on debugging for error handling in libiscsi module. "
63 "Set to 1 to turn on, and zero to turn off. Default is off.");
64
65#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...) \
66 do { \
67 if (iscsi_dbg_lib_conn) \
68 iscsi_conn_printk(KERN_INFO, _conn, \
69 "%s " dbg_fmt, \
70 __func__, ##arg); \
71 } while (0);
72
73#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...) \
74 do { \
75 if (iscsi_dbg_lib_session) \
76 iscsi_session_printk(KERN_INFO, _session, \
77 "%s " dbg_fmt, \
78 __func__, ##arg); \
79 } while (0);
80
81#define ISCSI_DBG_EH(_session, dbg_fmt, arg...) \
82 do { \
83 if (iscsi_dbg_lib_eh) \
84 iscsi_session_printk(KERN_INFO, _session, \
85 "%s " dbg_fmt, \
86 __func__, ##arg); \
87 } while (0);
88
89inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
90{
91 struct Scsi_Host *shost = conn->session->host;
92 struct iscsi_host *ihost = shost_priv(shost);
93
94 if (ihost->workq)
95 queue_work(ihost->workq, &conn->xmitwork);
96}
97EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
98
99static void __iscsi_update_cmdsn(struct iscsi_session *session,
100 uint32_t exp_cmdsn, uint32_t max_cmdsn)
101{
102 /*
103 * standard specifies this check for when to update expected and
104 * max sequence numbers
105 */
106 if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1))
107 return;
108
109 if (exp_cmdsn != session->exp_cmdsn &&
110 !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn))
111 session->exp_cmdsn = exp_cmdsn;
112
113 if (max_cmdsn != session->max_cmdsn &&
114 !iscsi_sna_lt(max_cmdsn, session->max_cmdsn))
115 session->max_cmdsn = max_cmdsn;
116}
117
118void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
119{
120 __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn),
121 be32_to_cpu(hdr->max_cmdsn));
122}
123EXPORT_SYMBOL_GPL(iscsi_update_cmdsn);
124
125/**
126 * iscsi_prep_data_out_pdu - initialize Data-Out
127 * @task: scsi command task
128 * @r2t: R2T info
129 * @hdr: iscsi data in pdu
130 *
131 * Notes:
132 * Initialize Data-Out within this R2T sequence and finds
133 * proper data_offset within this SCSI command.
134 *
135 * This function is called with connection lock taken.
136 **/
137void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t,
138 struct iscsi_data *hdr)
139{
140 struct iscsi_conn *conn = task->conn;
141 unsigned int left = r2t->data_length - r2t->sent;
142
143 task->hdr_len = sizeof(struct iscsi_data);
144
145 memset(hdr, 0, sizeof(struct iscsi_data));
146 hdr->ttt = r2t->ttt;
147 hdr->datasn = cpu_to_be32(r2t->datasn);
148 r2t->datasn++;
149 hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
150 hdr->lun = task->lun;
151 hdr->itt = task->hdr_itt;
152 hdr->exp_statsn = r2t->exp_statsn;
153 hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent);
154 if (left > conn->max_xmit_dlength) {
155 hton24(hdr->dlength, conn->max_xmit_dlength);
156 r2t->data_count = conn->max_xmit_dlength;
157 hdr->flags = 0;
158 } else {
159 hton24(hdr->dlength, left);
160 r2t->data_count = left;
161 hdr->flags = ISCSI_FLAG_CMD_FINAL;
162 }
163 conn->dataout_pdus_cnt++;
164}
165EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu);
166
167static int iscsi_add_hdr(struct iscsi_task *task, unsigned len)
168{
169 unsigned exp_len = task->hdr_len + len;
170
171 if (exp_len > task->hdr_max) {
172 WARN_ON(1);
173 return -EINVAL;
174 }
175
176 WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */
177 task->hdr_len = exp_len;
178 return 0;
179}
180
181/*
182 * make an extended cdb AHS
183 */
184static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
185{
186 struct scsi_cmnd *cmd = task->sc;
187 unsigned rlen, pad_len;
188 unsigned short ahslength;
189 struct iscsi_ecdb_ahdr *ecdb_ahdr;
190 int rc;
191
192 ecdb_ahdr = iscsi_next_hdr(task);
193 rlen = cmd->cmd_len - ISCSI_CDB_SIZE;
194
195 BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb));
196 ahslength = rlen + sizeof(ecdb_ahdr->reserved);
197
198 pad_len = iscsi_padding(rlen);
199
200 rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) +
201 sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len);
202 if (rc)
203 return rc;
204
205 if (pad_len)
206 memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len);
207
208 ecdb_ahdr->ahslength = cpu_to_be16(ahslength);
209 ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB;
210 ecdb_ahdr->reserved = 0;
211 memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
212
213 ISCSI_DBG_SESSION(task->conn->session,
214 "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
215 "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
216 "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
217 task->hdr_len);
218 return 0;
219}
220
221static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
222{
223 struct scsi_cmnd *sc = task->sc;
224 struct iscsi_rlength_ahdr *rlen_ahdr;
225 int rc;
226
227 rlen_ahdr = iscsi_next_hdr(task);
228 rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr));
229 if (rc)
230 return rc;
231
232 rlen_ahdr->ahslength =
233 cpu_to_be16(sizeof(rlen_ahdr->read_length) +
234 sizeof(rlen_ahdr->reserved));
235 rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH;
236 rlen_ahdr->reserved = 0;
237 rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
238
239 ISCSI_DBG_SESSION(task->conn->session,
240 "bidi-in rlen_ahdr->read_length(%d) "
241 "rlen_ahdr->ahslength(%d)\n",
242 be32_to_cpu(rlen_ahdr->read_length),
243 be16_to_cpu(rlen_ahdr->ahslength));
244 return 0;
245}
246
247/**
248 * iscsi_check_tmf_restrictions - check if a task is affected by TMF
249 * @task: iscsi task
250 * @opcode: opcode to check for
251 *
252 * During TMF a task has to be checked if it's affected.
253 * All unrelated I/O can be passed through, but I/O to the
254 * affected LUN should be restricted.
255 * If 'fast_abort' is set we won't be sending any I/O to the
256 * affected LUN.
257 * Otherwise the target is waiting for all TTTs to be completed,
258 * so we have to send all outstanding Data-Out PDUs to the target.
259 */
260static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode)
261{
262 struct iscsi_conn *conn = task->conn;
263 struct iscsi_tm *tmf = &conn->tmhdr;
264 u64 hdr_lun;
265
266 if (conn->tmf_state == TMF_INITIAL)
267 return 0;
268
269 if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC)
270 return 0;
271
272 switch (ISCSI_TM_FUNC_VALUE(tmf)) {
273 case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
274 /*
275 * Allow PDUs for unrelated LUNs
276 */
277 hdr_lun = scsilun_to_int(&tmf->lun);
278 if (hdr_lun != task->sc->device->lun)
279 return 0;
280 /* fall through */
281 case ISCSI_TM_FUNC_TARGET_WARM_RESET:
282 /*
283 * Fail all SCSI cmd PDUs
284 */
285 if (opcode != ISCSI_OP_SCSI_DATA_OUT) {
286 iscsi_conn_printk(KERN_INFO, conn,
287 "task [op %x/%x itt "
288 "0x%x/0x%x] "
289 "rejected.\n",
290 task->hdr->opcode, opcode,
291 task->itt, task->hdr_itt);
292 return -EACCES;
293 }
294 /*
295 * And also all data-out PDUs in response to R2T
296 * if fast_abort is set.
297 */
298 if (conn->session->fast_abort) {
299 iscsi_conn_printk(KERN_INFO, conn,
300 "task [op %x/%x itt "
301 "0x%x/0x%x] fast abort.\n",
302 task->hdr->opcode, opcode,
303 task->itt, task->hdr_itt);
304 return -EACCES;
305 }
306 break;
307 case ISCSI_TM_FUNC_ABORT_TASK:
308 /*
309 * the caller has already checked if the task
310 * they want to abort was in the pending queue so if
311 * we are here the cmd pdu has gone out already, and
312 * we will only hit this for data-outs
313 */
314 if (opcode == ISCSI_OP_SCSI_DATA_OUT &&
315 task->hdr_itt == tmf->rtt) {
316 ISCSI_DBG_SESSION(conn->session,
317 "Preventing task %x/%x from sending "
318 "data-out due to abort task in "
319 "progress\n", task->itt,
320 task->hdr_itt);
321 return -EACCES;
322 }
323 break;
324 }
325
326 return 0;
327}
328
329/**
330 * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu
331 * @task: iscsi task
332 *
333 * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set
334 * fields like dlength or final based on how much data it sends
335 */
336static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
337{
338 struct iscsi_conn *conn = task->conn;
339 struct iscsi_session *session = conn->session;
340 struct scsi_cmnd *sc = task->sc;
341 struct iscsi_scsi_req *hdr;
342 unsigned hdrlength, cmd_len, transfer_length;
343 itt_t itt;
344 int rc;
345
346 rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD);
347 if (rc)
348 return rc;
349
350 if (conn->session->tt->alloc_pdu) {
351 rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD);
352 if (rc)
353 return rc;
354 }
355 hdr = (struct iscsi_scsi_req *)task->hdr;
356 itt = hdr->itt;
357 memset(hdr, 0, sizeof(*hdr));
358
359 if (session->tt->parse_pdu_itt)
360 hdr->itt = task->hdr_itt = itt;
361 else
362 hdr->itt = task->hdr_itt = build_itt(task->itt,
363 task->conn->session->age);
364 task->hdr_len = 0;
365 rc = iscsi_add_hdr(task, sizeof(*hdr));
366 if (rc)
367 return rc;
368 hdr->opcode = ISCSI_OP_SCSI_CMD;
369 hdr->flags = ISCSI_ATTR_SIMPLE;
370 int_to_scsilun(sc->device->lun, &hdr->lun);
371 task->lun = hdr->lun;
372 hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
373 cmd_len = sc->cmd_len;
374 if (cmd_len < ISCSI_CDB_SIZE)
375 memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len);
376 else if (cmd_len > ISCSI_CDB_SIZE) {
377 rc = iscsi_prep_ecdb_ahs(task);
378 if (rc)
379 return rc;
380 cmd_len = ISCSI_CDB_SIZE;
381 }
382 memcpy(hdr->cdb, sc->cmnd, cmd_len);
383
384 task->imm_count = 0;
385 if (scsi_bidi_cmnd(sc)) {
386 hdr->flags |= ISCSI_FLAG_CMD_READ;
387 rc = iscsi_prep_bidi_ahs(task);
388 if (rc)
389 return rc;
390 }
391
392 if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL)
393 task->protected = true;
394
395 transfer_length = scsi_transfer_length(sc);
396 hdr->data_length = cpu_to_be32(transfer_length);
397 if (sc->sc_data_direction == DMA_TO_DEVICE) {
398 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
399
400 hdr->flags |= ISCSI_FLAG_CMD_WRITE;
401 /*
402 * Write counters:
403 *
404 * imm_count bytes to be sent right after
405 * SCSI PDU Header
406 *
407 * unsol_count bytes(as Data-Out) to be sent
408 * without R2T ack right after
409 * immediate data
410 *
411 * r2t data_length bytes to be sent via R2T ack's
412 *
413 * pad_count bytes to be sent as zero-padding
414 */
415 memset(r2t, 0, sizeof(*r2t));
416
417 if (session->imm_data_en) {
418 if (transfer_length >= session->first_burst)
419 task->imm_count = min(session->first_burst,
420 conn->max_xmit_dlength);
421 else
422 task->imm_count = min(transfer_length,
423 conn->max_xmit_dlength);
424 hton24(hdr->dlength, task->imm_count);
425 } else
426 zero_data(hdr->dlength);
427
428 if (!session->initial_r2t_en) {
429 r2t->data_length = min(session->first_burst,
430 transfer_length) -
431 task->imm_count;
432 r2t->data_offset = task->imm_count;
433 r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
434 r2t->exp_statsn = cpu_to_be32(conn->exp_statsn);
435 }
436
437 if (!task->unsol_r2t.data_length)
438 /* No unsolicit Data-Out's */
439 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
440 } else {
441 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
442 zero_data(hdr->dlength);
443
444 if (sc->sc_data_direction == DMA_FROM_DEVICE)
445 hdr->flags |= ISCSI_FLAG_CMD_READ;
446 }
447
448 /* calculate size of additional header segments (AHSs) */
449 hdrlength = task->hdr_len - sizeof(*hdr);
450
451 WARN_ON(hdrlength & (ISCSI_PAD_LEN-1));
452 hdrlength /= ISCSI_PAD_LEN;
453
454 WARN_ON(hdrlength >= 256);
455 hdr->hlength = hdrlength & 0xFF;
456 hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
457
458 if (session->tt->init_task && session->tt->init_task(task))
459 return -EIO;
460
461 task->state = ISCSI_TASK_RUNNING;
462 session->cmdsn++;
463
464 conn->scsicmd_pdus_cnt++;
465 ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
466 "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
467 scsi_bidi_cmnd(sc) ? "bidirectional" :
468 sc->sc_data_direction == DMA_TO_DEVICE ?
469 "write" : "read", conn->id, sc, sc->cmnd[0],
470 task->itt, transfer_length,
471 scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
472 session->cmdsn,
473 session->max_cmdsn - session->exp_cmdsn + 1);
474 return 0;
475}
476
477/**
478 * iscsi_free_task - free a task
479 * @task: iscsi cmd task
480 *
481 * Must be called with session back_lock.
482 * This function returns the scsi command to scsi-ml or cleans
483 * up mgmt tasks then returns the task to the pool.
484 */
485static void iscsi_free_task(struct iscsi_task *task)
486{
487 struct iscsi_conn *conn = task->conn;
488 struct iscsi_session *session = conn->session;
489 struct scsi_cmnd *sc = task->sc;
490 int oldstate = task->state;
491
492 ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
493 task->itt, task->state, task->sc);
494
495 session->tt->cleanup_task(task);
496 task->state = ISCSI_TASK_FREE;
497 task->sc = NULL;
498 /*
499 * login task is preallocated so do not free
500 */
501 if (conn->login_task == task)
502 return;
503
504 kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*));
505
506 if (sc) {
507 /* SCSI eh reuses commands to verify us */
508 sc->SCp.ptr = NULL;
509 /*
510 * queue command may call this to free the task, so
511 * it will decide how to return sc to scsi-ml.
512 */
513 if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
514 sc->scsi_done(sc);
515 }
516}
517
518void __iscsi_get_task(struct iscsi_task *task)
519{
520 refcount_inc(&task->refcount);
521}
522EXPORT_SYMBOL_GPL(__iscsi_get_task);
523
524void __iscsi_put_task(struct iscsi_task *task)
525{
526 if (refcount_dec_and_test(&task->refcount))
527 iscsi_free_task(task);
528}
529EXPORT_SYMBOL_GPL(__iscsi_put_task);
530
531void iscsi_put_task(struct iscsi_task *task)
532{
533 struct iscsi_session *session = task->conn->session;
534
535 /* regular RX path uses back_lock */
536 spin_lock_bh(&session->back_lock);
537 __iscsi_put_task(task);
538 spin_unlock_bh(&session->back_lock);
539}
540EXPORT_SYMBOL_GPL(iscsi_put_task);
541
542/**
543 * iscsi_complete_task - finish a task
544 * @task: iscsi cmd task
545 * @state: state to complete task with
546 *
547 * Must be called with session back_lock.
548 */
549static void iscsi_complete_task(struct iscsi_task *task, int state)
550{
551 struct iscsi_conn *conn = task->conn;
552
553 ISCSI_DBG_SESSION(conn->session,
554 "complete task itt 0x%x state %d sc %p\n",
555 task->itt, task->state, task->sc);
556 if (task->state == ISCSI_TASK_COMPLETED ||
557 task->state == ISCSI_TASK_ABRT_TMF ||
558 task->state == ISCSI_TASK_ABRT_SESS_RECOV ||
559 task->state == ISCSI_TASK_REQUEUE_SCSIQ)
560 return;
561 WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
562 task->state = state;
563
564 spin_lock_bh(&conn->taskqueuelock);
565 if (!list_empty(&task->running)) {
566 pr_debug_once("%s while task on list", __func__);
567 list_del_init(&task->running);
568 }
569 spin_unlock_bh(&conn->taskqueuelock);
570
571 if (conn->task == task)
572 conn->task = NULL;
573
574 if (conn->ping_task == task)
575 conn->ping_task = NULL;
576
577 /* release get from queueing */
578 __iscsi_put_task(task);
579}
580
581/**
582 * iscsi_complete_scsi_task - finish scsi task normally
583 * @task: iscsi task for scsi cmd
584 * @exp_cmdsn: expected cmd sn in cpu format
585 * @max_cmdsn: max cmd sn in cpu format
586 *
587 * This is used when drivers do not need or cannot perform
588 * lower level pdu processing.
589 *
590 * Called with session back_lock
591 */
592void iscsi_complete_scsi_task(struct iscsi_task *task,
593 uint32_t exp_cmdsn, uint32_t max_cmdsn)
594{
595 struct iscsi_conn *conn = task->conn;
596
597 ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt);
598
599 conn->last_recv = jiffies;
600 __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn);
601 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
602}
603EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task);
604
605
606/*
607 * session back_lock must be held and if not called for a task that is
608 * still pending or from the xmit thread, then xmit thread must
609 * be suspended.
610 */
611static void fail_scsi_task(struct iscsi_task *task, int err)
612{
613 struct iscsi_conn *conn = task->conn;
614 struct scsi_cmnd *sc;
615 int state;
616
617 /*
618 * if a command completes and we get a successful tmf response
619 * we will hit this because the scsi eh abort code does not take
620 * a ref to the task.
621 */
622 sc = task->sc;
623 if (!sc)
624 return;
625
626 if (task->state == ISCSI_TASK_PENDING) {
627 /*
628 * cmd never made it to the xmit thread, so we should not count
629 * the cmd in the sequencing
630 */
631 conn->session->queued_cmdsn--;
632 /* it was never sent so just complete like normal */
633 state = ISCSI_TASK_COMPLETED;
634 } else if (err == DID_TRANSPORT_DISRUPTED)
635 state = ISCSI_TASK_ABRT_SESS_RECOV;
636 else
637 state = ISCSI_TASK_ABRT_TMF;
638
639 sc->result = err << 16;
640 if (!scsi_bidi_cmnd(sc))
641 scsi_set_resid(sc, scsi_bufflen(sc));
642 else {
643 scsi_out(sc)->resid = scsi_out(sc)->length;
644 scsi_in(sc)->resid = scsi_in(sc)->length;
645 }
646
647 /* regular RX path uses back_lock */
648 spin_lock_bh(&conn->session->back_lock);
649 iscsi_complete_task(task, state);
650 spin_unlock_bh(&conn->session->back_lock);
651}
652
653static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
654 struct iscsi_task *task)
655{
656 struct iscsi_session *session = conn->session;
657 struct iscsi_hdr *hdr = task->hdr;
658 struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
659 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
660
661 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
662 return -ENOTCONN;
663
664 if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT)
665 nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
666 /*
667 * pre-format CmdSN for outgoing PDU.
668 */
669 nop->cmdsn = cpu_to_be32(session->cmdsn);
670 if (hdr->itt != RESERVED_ITT) {
671 /*
672 * TODO: We always use immediate for normal session pdus.
673 * If we start to send tmfs or nops as non-immediate then
674 * we should start checking the cmdsn numbers for mgmt tasks.
675 *
676 * During discovery sessions iscsid sends TEXT as non immediate,
677 * but we always only send one PDU at a time.
678 */
679 if (conn->c_stage == ISCSI_CONN_STARTED &&
680 !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
681 session->queued_cmdsn++;
682 session->cmdsn++;
683 }
684 }
685
686 if (session->tt->init_task && session->tt->init_task(task))
687 return -EIO;
688
689 if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT)
690 session->state = ISCSI_STATE_LOGGING_OUT;
691
692 task->state = ISCSI_TASK_RUNNING;
693 ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
694 "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
695 hdr->itt, task->data_count);
696 return 0;
697}
698
699static struct iscsi_task *
700__iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
701 char *data, uint32_t data_size)
702{
703 struct iscsi_session *session = conn->session;
704 struct iscsi_host *ihost = shost_priv(session->host);
705 uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK;
706 struct iscsi_task *task;
707 itt_t itt;
708
709 if (session->state == ISCSI_STATE_TERMINATE)
710 return NULL;
711
712 if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) {
713 /*
714 * Login and Text are sent serially, in
715 * request-followed-by-response sequence.
716 * Same task can be used. Same ITT must be used.
717 * Note that login_task is preallocated at conn_create().
718 */
719 if (conn->login_task->state != ISCSI_TASK_FREE) {
720 iscsi_conn_printk(KERN_ERR, conn, "Login/Text in "
721 "progress. Cannot start new task.\n");
722 return NULL;
723 }
724
725 if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) {
726 iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN);
727 return NULL;
728 }
729
730 task = conn->login_task;
731 } else {
732 if (session->state != ISCSI_STATE_LOGGED_IN)
733 return NULL;
734
735 if (data_size != 0) {
736 iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode);
737 return NULL;
738 }
739
740 BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
741 BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
742
743 if (!kfifo_out(&session->cmdpool.queue,
744 (void*)&task, sizeof(void*)))
745 return NULL;
746 }
747 /*
748 * released in complete pdu for task we expect a response for, and
749 * released by the lld when it has transmitted the task for
750 * pdus we do not expect a response for.
751 */
752 refcount_set(&task->refcount, 1);
753 task->conn = conn;
754 task->sc = NULL;
755 INIT_LIST_HEAD(&task->running);
756 task->state = ISCSI_TASK_PENDING;
757
758 if (data_size) {
759 memcpy(task->data, data, data_size);
760 task->data_count = data_size;
761 } else
762 task->data_count = 0;
763
764 if (conn->session->tt->alloc_pdu) {
765 if (conn->session->tt->alloc_pdu(task, hdr->opcode)) {
766 iscsi_conn_printk(KERN_ERR, conn, "Could not allocate "
767 "pdu for mgmt task.\n");
768 goto free_task;
769 }
770 }
771
772 itt = task->hdr->itt;
773 task->hdr_len = sizeof(struct iscsi_hdr);
774 memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
775
776 if (hdr->itt != RESERVED_ITT) {
777 if (session->tt->parse_pdu_itt)
778 task->hdr->itt = itt;
779 else
780 task->hdr->itt = build_itt(task->itt,
781 task->conn->session->age);
782 }
783
784 if (!ihost->workq) {
785 if (iscsi_prep_mgmt_task(conn, task))
786 goto free_task;
787
788 if (session->tt->xmit_task(task))
789 goto free_task;
790 } else {
791 spin_lock_bh(&conn->taskqueuelock);
792 list_add_tail(&task->running, &conn->mgmtqueue);
793 spin_unlock_bh(&conn->taskqueuelock);
794 iscsi_conn_queue_work(conn);
795 }
796
797 return task;
798
799free_task:
800 /* regular RX path uses back_lock */
801 spin_lock(&session->back_lock);
802 __iscsi_put_task(task);
803 spin_unlock(&session->back_lock);
804 return NULL;
805}
806
807int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr,
808 char *data, uint32_t data_size)
809{
810 struct iscsi_conn *conn = cls_conn->dd_data;
811 struct iscsi_session *session = conn->session;
812 int err = 0;
813
814 spin_lock_bh(&session->frwd_lock);
815 if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size))
816 err = -EPERM;
817 spin_unlock_bh(&session->frwd_lock);
818 return err;
819}
820EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu);
821
822/**
823 * iscsi_cmd_rsp - SCSI Command Response processing
824 * @conn: iscsi connection
825 * @hdr: iscsi header
826 * @task: scsi command task
827 * @data: cmd data buffer
828 * @datalen: len of buffer
829 *
830 * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and
831 * then completes the command and task.
832 **/
833static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
834 struct iscsi_task *task, char *data,
835 int datalen)
836{
837 struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr;
838 struct iscsi_session *session = conn->session;
839 struct scsi_cmnd *sc = task->sc;
840
841 iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
842 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
843
844 sc->result = (DID_OK << 16) | rhdr->cmd_status;
845
846 if (task->protected) {
847 sector_t sector;
848 u8 ascq;
849
850 /**
851 * Transports that didn't implement check_protection
852 * callback but still published T10-PI support to scsi-mid
853 * deserve this BUG_ON.
854 **/
855 BUG_ON(!session->tt->check_protection);
856
857 ascq = session->tt->check_protection(task, §or);
858 if (ascq) {
859 sc->result = DRIVER_SENSE << 24 |
860 SAM_STAT_CHECK_CONDITION;
861 scsi_build_sense_buffer(1, sc->sense_buffer,
862 ILLEGAL_REQUEST, 0x10, ascq);
863 scsi_set_sense_information(sc->sense_buffer,
864 SCSI_SENSE_BUFFERSIZE,
865 sector);
866 goto out;
867 }
868 }
869
870 if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
871 sc->result = DID_ERROR << 16;
872 goto out;
873 }
874
875 if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) {
876 uint16_t senselen;
877
878 if (datalen < 2) {
879invalid_datalen:
880 iscsi_conn_printk(KERN_ERR, conn,
881 "Got CHECK_CONDITION but invalid data "
882 "buffer size of %d\n", datalen);
883 sc->result = DID_BAD_TARGET << 16;
884 goto out;
885 }
886
887 senselen = get_unaligned_be16(data);
888 if (datalen < senselen)
889 goto invalid_datalen;
890
891 memcpy(sc->sense_buffer, data + 2,
892 min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
893 ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
894 min_t(uint16_t, senselen,
895 SCSI_SENSE_BUFFERSIZE));
896 }
897
898 if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
899 ISCSI_FLAG_CMD_BIDI_OVERFLOW)) {
900 int res_count = be32_to_cpu(rhdr->bi_residual_count);
901
902 if (scsi_bidi_cmnd(sc) && res_count > 0 &&
903 (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW ||
904 res_count <= scsi_in(sc)->length))
905 scsi_in(sc)->resid = res_count;
906 else
907 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
908 }
909
910 if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW |
911 ISCSI_FLAG_CMD_OVERFLOW)) {
912 int res_count = be32_to_cpu(rhdr->residual_count);
913
914 if (res_count > 0 &&
915 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
916 res_count <= scsi_bufflen(sc)))
917 /* write side for bidi or uni-io set_resid */
918 scsi_set_resid(sc, res_count);
919 else
920 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
921 }
922out:
923 ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n",
924 sc, sc->result, task->itt);
925 conn->scsirsp_pdus_cnt++;
926 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
927}
928
929/**
930 * iscsi_data_in_rsp - SCSI Data-In Response processing
931 * @conn: iscsi connection
932 * @hdr: iscsi pdu
933 * @task: scsi command task
934 **/
935static void
936iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
937 struct iscsi_task *task)
938{
939 struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr;
940 struct scsi_cmnd *sc = task->sc;
941
942 if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS))
943 return;
944
945 iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr);
946 sc->result = (DID_OK << 16) | rhdr->cmd_status;
947 conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
948 if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
949 ISCSI_FLAG_DATA_OVERFLOW)) {
950 int res_count = be32_to_cpu(rhdr->residual_count);
951
952 if (res_count > 0 &&
953 (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
954 res_count <= scsi_in(sc)->length))
955 scsi_in(sc)->resid = res_count;
956 else
957 sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
958 }
959
960 ISCSI_DBG_SESSION(conn->session, "data in with status done "
961 "[sc %p res %d itt 0x%x]\n",
962 sc, sc->result, task->itt);
963 conn->scsirsp_pdus_cnt++;
964 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
965}
966
967static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
968{
969 struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr;
970
971 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
972 conn->tmfrsp_pdus_cnt++;
973
974 if (conn->tmf_state != TMF_QUEUED)
975 return;
976
977 if (tmf->response == ISCSI_TMF_RSP_COMPLETE)
978 conn->tmf_state = TMF_SUCCESS;
979 else if (tmf->response == ISCSI_TMF_RSP_NO_TASK)
980 conn->tmf_state = TMF_NOT_FOUND;
981 else
982 conn->tmf_state = TMF_FAILED;
983 wake_up(&conn->ehwait);
984}
985
986static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr)
987{
988 struct iscsi_nopout hdr;
989 struct iscsi_task *task;
990
991 if (!rhdr && conn->ping_task)
992 return -EINVAL;
993
994 memset(&hdr, 0, sizeof(struct iscsi_nopout));
995 hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE;
996 hdr.flags = ISCSI_FLAG_CMD_FINAL;
997
998 if (rhdr) {
999 hdr.lun = rhdr->lun;
1000 hdr.ttt = rhdr->ttt;
1001 hdr.itt = RESERVED_ITT;
1002 } else
1003 hdr.ttt = RESERVED_ITT;
1004
1005 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0);
1006 if (!task) {
1007 iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n");
1008 return -EIO;
1009 } else if (!rhdr) {
1010 /* only track our nops */
1011 conn->ping_task = task;
1012 conn->last_ping = jiffies;
1013 }
1014
1015 return 0;
1016}
1017
1018static int iscsi_nop_out_rsp(struct iscsi_task *task,
1019 struct iscsi_nopin *nop, char *data, int datalen)
1020{
1021 struct iscsi_conn *conn = task->conn;
1022 int rc = 0;
1023
1024 if (conn->ping_task != task) {
1025 /*
1026 * If this is not in response to one of our
1027 * nops then it must be from userspace.
1028 */
1029 if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop,
1030 data, datalen))
1031 rc = ISCSI_ERR_CONN_FAILED;
1032 } else
1033 mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout);
1034 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1035 return rc;
1036}
1037
1038static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1039 char *data, int datalen)
1040{
1041 struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
1042 struct iscsi_hdr rejected_pdu;
1043 int opcode, rc = 0;
1044
1045 conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
1046
1047 if (ntoh24(reject->dlength) > datalen ||
1048 ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) {
1049 iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected "
1050 "pdu. Invalid data length (pdu dlength "
1051 "%u, datalen %d\n", ntoh24(reject->dlength),
1052 datalen);
1053 return ISCSI_ERR_PROTO;
1054 }
1055 memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
1056 opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK;
1057
1058 switch (reject->reason) {
1059 case ISCSI_REASON_DATA_DIGEST_ERROR:
1060 iscsi_conn_printk(KERN_ERR, conn,
1061 "pdu (op 0x%x itt 0x%x) rejected "
1062 "due to DataDigest error.\n",
1063 opcode, rejected_pdu.itt);
1064 break;
1065 case ISCSI_REASON_IMM_CMD_REJECT:
1066 iscsi_conn_printk(KERN_ERR, conn,
1067 "pdu (op 0x%x itt 0x%x) rejected. Too many "
1068 "immediate commands.\n",
1069 opcode, rejected_pdu.itt);
1070 /*
1071 * We only send one TMF at a time so if the target could not
1072 * handle it, then it should get fixed (RFC mandates that
1073 * a target can handle one immediate TMF per conn).
1074 *
1075 * For nops-outs, we could have sent more than one if
1076 * the target is sending us lots of nop-ins
1077 */
1078 if (opcode != ISCSI_OP_NOOP_OUT)
1079 return 0;
1080
1081 if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
1082 /*
1083 * nop-out in response to target's nop-out rejected.
1084 * Just resend.
1085 */
1086 /* In RX path we are under back lock */
1087 spin_unlock(&conn->session->back_lock);
1088 spin_lock(&conn->session->frwd_lock);
1089 iscsi_send_nopout(conn,
1090 (struct iscsi_nopin*)&rejected_pdu);
1091 spin_unlock(&conn->session->frwd_lock);
1092 spin_lock(&conn->session->back_lock);
1093 } else {
1094 struct iscsi_task *task;
1095 /*
1096 * Our nop as ping got dropped. We know the target
1097 * and transport are ok so just clean up
1098 */
1099 task = iscsi_itt_to_task(conn, rejected_pdu.itt);
1100 if (!task) {
1101 iscsi_conn_printk(KERN_ERR, conn,
1102 "Invalid pdu reject. Could "
1103 "not lookup rejected task.\n");
1104 rc = ISCSI_ERR_BAD_ITT;
1105 } else
1106 rc = iscsi_nop_out_rsp(task,
1107 (struct iscsi_nopin*)&rejected_pdu,
1108 NULL, 0);
1109 }
1110 break;
1111 default:
1112 iscsi_conn_printk(KERN_ERR, conn,
1113 "pdu (op 0x%x itt 0x%x) rejected. Reason "
1114 "code 0x%x\n", rejected_pdu.opcode,
1115 rejected_pdu.itt, reject->reason);
1116 break;
1117 }
1118 return rc;
1119}
1120
1121/**
1122 * iscsi_itt_to_task - look up task by itt
1123 * @conn: iscsi connection
1124 * @itt: itt
1125 *
1126 * This should be used for mgmt tasks like login and nops, or if
1127 * the LDD's itt space does not include the session age.
1128 *
1129 * The session back_lock must be held.
1130 */
1131struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
1132{
1133 struct iscsi_session *session = conn->session;
1134 int i;
1135
1136 if (itt == RESERVED_ITT)
1137 return NULL;
1138
1139 if (session->tt->parse_pdu_itt)
1140 session->tt->parse_pdu_itt(conn, itt, &i, NULL);
1141 else
1142 i = get_itt(itt);
1143 if (i >= session->cmds_max)
1144 return NULL;
1145
1146 return session->cmds[i];
1147}
1148EXPORT_SYMBOL_GPL(iscsi_itt_to_task);
1149
1150/**
1151 * __iscsi_complete_pdu - complete pdu
1152 * @conn: iscsi conn
1153 * @hdr: iscsi header
1154 * @data: data buffer
1155 * @datalen: len of data buffer
1156 *
1157 * Completes pdu processing by freeing any resources allocated at
1158 * queuecommand or send generic. session back_lock must be held and verify
1159 * itt must have been called.
1160 */
1161int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1162 char *data, int datalen)
1163{
1164 struct iscsi_session *session = conn->session;
1165 int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
1166 struct iscsi_task *task;
1167 uint32_t itt;
1168
1169 conn->last_recv = jiffies;
1170 rc = iscsi_verify_itt(conn, hdr->itt);
1171 if (rc)
1172 return rc;
1173
1174 if (hdr->itt != RESERVED_ITT)
1175 itt = get_itt(hdr->itt);
1176 else
1177 itt = ~0U;
1178
1179 ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
1180 opcode, conn->id, itt, datalen);
1181
1182 if (itt == ~0U) {
1183 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1184
1185 switch(opcode) {
1186 case ISCSI_OP_NOOP_IN:
1187 if (datalen) {
1188 rc = ISCSI_ERR_PROTO;
1189 break;
1190 }
1191
1192 if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG))
1193 break;
1194
1195 /* In RX path we are under back lock */
1196 spin_unlock(&session->back_lock);
1197 spin_lock(&session->frwd_lock);
1198 iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr);
1199 spin_unlock(&session->frwd_lock);
1200 spin_lock(&session->back_lock);
1201 break;
1202 case ISCSI_OP_REJECT:
1203 rc = iscsi_handle_reject(conn, hdr, data, datalen);
1204 break;
1205 case ISCSI_OP_ASYNC_EVENT:
1206 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1207 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1208 rc = ISCSI_ERR_CONN_FAILED;
1209 break;
1210 default:
1211 rc = ISCSI_ERR_BAD_OPCODE;
1212 break;
1213 }
1214 goto out;
1215 }
1216
1217 switch(opcode) {
1218 case ISCSI_OP_SCSI_CMD_RSP:
1219 case ISCSI_OP_SCSI_DATA_IN:
1220 task = iscsi_itt_to_ctask(conn, hdr->itt);
1221 if (!task)
1222 return ISCSI_ERR_BAD_ITT;
1223 task->last_xfer = jiffies;
1224 break;
1225 case ISCSI_OP_R2T:
1226 /*
1227 * LLD handles R2Ts if they need to.
1228 */
1229 return 0;
1230 case ISCSI_OP_LOGOUT_RSP:
1231 case ISCSI_OP_LOGIN_RSP:
1232 case ISCSI_OP_TEXT_RSP:
1233 case ISCSI_OP_SCSI_TMFUNC_RSP:
1234 case ISCSI_OP_NOOP_IN:
1235 task = iscsi_itt_to_task(conn, hdr->itt);
1236 if (!task)
1237 return ISCSI_ERR_BAD_ITT;
1238 break;
1239 default:
1240 return ISCSI_ERR_BAD_OPCODE;
1241 }
1242
1243 switch(opcode) {
1244 case ISCSI_OP_SCSI_CMD_RSP:
1245 iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
1246 break;
1247 case ISCSI_OP_SCSI_DATA_IN:
1248 iscsi_data_in_rsp(conn, hdr, task);
1249 break;
1250 case ISCSI_OP_LOGOUT_RSP:
1251 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1252 if (datalen) {
1253 rc = ISCSI_ERR_PROTO;
1254 break;
1255 }
1256 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1257 goto recv_pdu;
1258 case ISCSI_OP_LOGIN_RSP:
1259 case ISCSI_OP_TEXT_RSP:
1260 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1261 /*
1262 * login related PDU's exp_statsn is handled in
1263 * userspace
1264 */
1265 goto recv_pdu;
1266 case ISCSI_OP_SCSI_TMFUNC_RSP:
1267 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1268 if (datalen) {
1269 rc = ISCSI_ERR_PROTO;
1270 break;
1271 }
1272
1273 iscsi_tmf_rsp(conn, hdr);
1274 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1275 break;
1276 case ISCSI_OP_NOOP_IN:
1277 iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
1278 if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) {
1279 rc = ISCSI_ERR_PROTO;
1280 break;
1281 }
1282 conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
1283
1284 rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr,
1285 data, datalen);
1286 break;
1287 default:
1288 rc = ISCSI_ERR_BAD_OPCODE;
1289 break;
1290 }
1291
1292out:
1293 return rc;
1294recv_pdu:
1295 if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen))
1296 rc = ISCSI_ERR_CONN_FAILED;
1297 iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
1298 return rc;
1299}
1300EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
1301
1302int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
1303 char *data, int datalen)
1304{
1305 int rc;
1306
1307 spin_lock(&conn->session->back_lock);
1308 rc = __iscsi_complete_pdu(conn, hdr, data, datalen);
1309 spin_unlock(&conn->session->back_lock);
1310 return rc;
1311}
1312EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
1313
1314int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
1315{
1316 struct iscsi_session *session = conn->session;
1317 int age = 0, i = 0;
1318
1319 if (itt == RESERVED_ITT)
1320 return 0;
1321
1322 if (session->tt->parse_pdu_itt)
1323 session->tt->parse_pdu_itt(conn, itt, &i, &age);
1324 else {
1325 i = get_itt(itt);
1326 age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
1327 }
1328
1329 if (age != session->age) {
1330 iscsi_conn_printk(KERN_ERR, conn,
1331 "received itt %x expected session age (%x)\n",
1332 (__force u32)itt, session->age);
1333 return ISCSI_ERR_BAD_ITT;
1334 }
1335
1336 if (i >= session->cmds_max) {
1337 iscsi_conn_printk(KERN_ERR, conn,
1338 "received invalid itt index %u (max cmds "
1339 "%u.\n", i, session->cmds_max);
1340 return ISCSI_ERR_BAD_ITT;
1341 }
1342 return 0;
1343}
1344EXPORT_SYMBOL_GPL(iscsi_verify_itt);
1345
1346/**
1347 * iscsi_itt_to_ctask - look up ctask by itt
1348 * @conn: iscsi connection
1349 * @itt: itt
1350 *
1351 * This should be used for cmd tasks.
1352 *
1353 * The session back_lock must be held.
1354 */
1355struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
1356{
1357 struct iscsi_task *task;
1358
1359 if (iscsi_verify_itt(conn, itt))
1360 return NULL;
1361
1362 task = iscsi_itt_to_task(conn, itt);
1363 if (!task || !task->sc)
1364 return NULL;
1365
1366 if (task->sc->SCp.phase != conn->session->age) {
1367 iscsi_session_printk(KERN_ERR, conn->session,
1368 "task's session age %d, expected %d\n",
1369 task->sc->SCp.phase, conn->session->age);
1370 return NULL;
1371 }
1372
1373 return task;
1374}
1375EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
1376
1377void iscsi_session_failure(struct iscsi_session *session,
1378 enum iscsi_err err)
1379{
1380 struct iscsi_conn *conn;
1381 struct device *dev;
1382
1383 spin_lock_bh(&session->frwd_lock);
1384 conn = session->leadconn;
1385 if (session->state == ISCSI_STATE_TERMINATE || !conn) {
1386 spin_unlock_bh(&session->frwd_lock);
1387 return;
1388 }
1389
1390 dev = get_device(&conn->cls_conn->dev);
1391 spin_unlock_bh(&session->frwd_lock);
1392 if (!dev)
1393 return;
1394 /*
1395 * if the host is being removed bypass the connection
1396 * recovery initialization because we are going to kill
1397 * the session.
1398 */
1399 if (err == ISCSI_ERR_INVALID_HOST)
1400 iscsi_conn_error_event(conn->cls_conn, err);
1401 else
1402 iscsi_conn_failure(conn, err);
1403 put_device(dev);
1404}
1405EXPORT_SYMBOL_GPL(iscsi_session_failure);
1406
1407void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
1408{
1409 struct iscsi_session *session = conn->session;
1410
1411 spin_lock_bh(&session->frwd_lock);
1412 if (session->state == ISCSI_STATE_FAILED) {
1413 spin_unlock_bh(&session->frwd_lock);
1414 return;
1415 }
1416
1417 if (conn->stop_stage == 0)
1418 session->state = ISCSI_STATE_FAILED;
1419 spin_unlock_bh(&session->frwd_lock);
1420
1421 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1422 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
1423 iscsi_conn_error_event(conn->cls_conn, err);
1424}
1425EXPORT_SYMBOL_GPL(iscsi_conn_failure);
1426
1427static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
1428{
1429 struct iscsi_session *session = conn->session;
1430
1431 /*
1432 * Check for iSCSI window and take care of CmdSN wrap-around
1433 */
1434 if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
1435 ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
1436 "%u MaxCmdSN %u CmdSN %u/%u\n",
1437 session->exp_cmdsn, session->max_cmdsn,
1438 session->cmdsn, session->queued_cmdsn);
1439 return -ENOSPC;
1440 }
1441 return 0;
1442}
1443
1444static int iscsi_xmit_task(struct iscsi_conn *conn)
1445{
1446 struct iscsi_task *task = conn->task;
1447 int rc;
1448
1449 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx))
1450 return -ENODATA;
1451
1452 __iscsi_get_task(task);
1453 spin_unlock_bh(&conn->session->frwd_lock);
1454 rc = conn->session->tt->xmit_task(task);
1455 spin_lock_bh(&conn->session->frwd_lock);
1456 if (!rc) {
1457 /* done with this task */
1458 task->last_xfer = jiffies;
1459 conn->task = NULL;
1460 }
1461 /* regular RX path uses back_lock */
1462 spin_lock(&conn->session->back_lock);
1463 __iscsi_put_task(task);
1464 spin_unlock(&conn->session->back_lock);
1465 return rc;
1466}
1467
1468/**
1469 * iscsi_requeue_task - requeue task to run from session workqueue
1470 * @task: task to requeue
1471 *
1472 * LLDs that need to run a task from the session workqueue should call
1473 * this. The session frwd_lock must be held. This should only be called
1474 * by software drivers.
1475 */
1476void iscsi_requeue_task(struct iscsi_task *task)
1477{
1478 struct iscsi_conn *conn = task->conn;
1479
1480 /*
1481 * this may be on the requeue list already if the xmit_task callout
1482 * is handling the r2ts while we are adding new ones
1483 */
1484 spin_lock_bh(&conn->taskqueuelock);
1485 if (list_empty(&task->running))
1486 list_add_tail(&task->running, &conn->requeue);
1487 spin_unlock_bh(&conn->taskqueuelock);
1488 iscsi_conn_queue_work(conn);
1489}
1490EXPORT_SYMBOL_GPL(iscsi_requeue_task);
1491
1492/**
1493 * iscsi_data_xmit - xmit any command into the scheduled connection
1494 * @conn: iscsi connection
1495 *
1496 * Notes:
1497 * The function can return -EAGAIN in which case the caller must
1498 * re-schedule it again later or recover. '0' return code means
1499 * successful xmit.
1500 **/
1501static int iscsi_data_xmit(struct iscsi_conn *conn)
1502{
1503 struct iscsi_task *task;
1504 int rc = 0;
1505
1506 spin_lock_bh(&conn->session->frwd_lock);
1507 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1508 ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
1509 spin_unlock_bh(&conn->session->frwd_lock);
1510 return -ENODATA;
1511 }
1512
1513 if (conn->task) {
1514 rc = iscsi_xmit_task(conn);
1515 if (rc)
1516 goto done;
1517 }
1518
1519 /*
1520 * process mgmt pdus like nops before commands since we should
1521 * only have one nop-out as a ping from us and targets should not
1522 * overflow us with nop-ins
1523 */
1524 spin_lock_bh(&conn->taskqueuelock);
1525check_mgmt:
1526 while (!list_empty(&conn->mgmtqueue)) {
1527 conn->task = list_entry(conn->mgmtqueue.next,
1528 struct iscsi_task, running);
1529 list_del_init(&conn->task->running);
1530 spin_unlock_bh(&conn->taskqueuelock);
1531 if (iscsi_prep_mgmt_task(conn, conn->task)) {
1532 /* regular RX path uses back_lock */
1533 spin_lock_bh(&conn->session->back_lock);
1534 __iscsi_put_task(conn->task);
1535 spin_unlock_bh(&conn->session->back_lock);
1536 conn->task = NULL;
1537 spin_lock_bh(&conn->taskqueuelock);
1538 continue;
1539 }
1540 rc = iscsi_xmit_task(conn);
1541 if (rc)
1542 goto done;
1543 spin_lock_bh(&conn->taskqueuelock);
1544 }
1545
1546 /* process pending command queue */
1547 while (!list_empty(&conn->cmdqueue)) {
1548 conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task,
1549 running);
1550 list_del_init(&conn->task->running);
1551 spin_unlock_bh(&conn->taskqueuelock);
1552 if (conn->session->state == ISCSI_STATE_LOGGING_OUT) {
1553 fail_scsi_task(conn->task, DID_IMM_RETRY);
1554 spin_lock_bh(&conn->taskqueuelock);
1555 continue;
1556 }
1557 rc = iscsi_prep_scsi_cmd_pdu(conn->task);
1558 if (rc) {
1559 if (rc == -ENOMEM || rc == -EACCES) {
1560 spin_lock_bh(&conn->taskqueuelock);
1561 list_add_tail(&conn->task->running,
1562 &conn->cmdqueue);
1563 conn->task = NULL;
1564 spin_unlock_bh(&conn->taskqueuelock);
1565 goto done;
1566 } else
1567 fail_scsi_task(conn->task, DID_ABORT);
1568 spin_lock_bh(&conn->taskqueuelock);
1569 continue;
1570 }
1571 rc = iscsi_xmit_task(conn);
1572 if (rc)
1573 goto done;
1574 /*
1575 * we could continuously get new task requests so
1576 * we need to check the mgmt queue for nops that need to
1577 * be sent to aviod starvation
1578 */
1579 spin_lock_bh(&conn->taskqueuelock);
1580 if (!list_empty(&conn->mgmtqueue))
1581 goto check_mgmt;
1582 }
1583
1584 while (!list_empty(&conn->requeue)) {
1585 /*
1586 * we always do fastlogout - conn stop code will clean up.
1587 */
1588 if (conn->session->state == ISCSI_STATE_LOGGING_OUT)
1589 break;
1590
1591 task = list_entry(conn->requeue.next, struct iscsi_task,
1592 running);
1593 if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT))
1594 break;
1595
1596 conn->task = task;
1597 list_del_init(&conn->task->running);
1598 conn->task->state = ISCSI_TASK_RUNNING;
1599 spin_unlock_bh(&conn->taskqueuelock);
1600 rc = iscsi_xmit_task(conn);
1601 if (rc)
1602 goto done;
1603 spin_lock_bh(&conn->taskqueuelock);
1604 if (!list_empty(&conn->mgmtqueue))
1605 goto check_mgmt;
1606 }
1607 spin_unlock_bh(&conn->taskqueuelock);
1608 spin_unlock_bh(&conn->session->frwd_lock);
1609 return -ENODATA;
1610
1611done:
1612 spin_unlock_bh(&conn->session->frwd_lock);
1613 return rc;
1614}
1615
1616static void iscsi_xmitworker(struct work_struct *work)
1617{
1618 struct iscsi_conn *conn =
1619 container_of(work, struct iscsi_conn, xmitwork);
1620 int rc;
1621 /*
1622 * serialize Xmit worker on a per-connection basis.
1623 */
1624 do {
1625 rc = iscsi_data_xmit(conn);
1626 } while (rc >= 0 || rc == -EAGAIN);
1627}
1628
1629static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn,
1630 struct scsi_cmnd *sc)
1631{
1632 struct iscsi_task *task;
1633
1634 if (!kfifo_out(&conn->session->cmdpool.queue,
1635 (void *) &task, sizeof(void *)))
1636 return NULL;
1637
1638 sc->SCp.phase = conn->session->age;
1639 sc->SCp.ptr = (char *) task;
1640
1641 refcount_set(&task->refcount, 1);
1642 task->state = ISCSI_TASK_PENDING;
1643 task->conn = conn;
1644 task->sc = sc;
1645 task->have_checked_conn = false;
1646 task->last_timeout = jiffies;
1647 task->last_xfer = jiffies;
1648 task->protected = false;
1649 INIT_LIST_HEAD(&task->running);
1650 return task;
1651}
1652
1653enum {
1654 FAILURE_BAD_HOST = 1,
1655 FAILURE_SESSION_FAILED,
1656 FAILURE_SESSION_FREED,
1657 FAILURE_WINDOW_CLOSED,
1658 FAILURE_OOM,
1659 FAILURE_SESSION_TERMINATE,
1660 FAILURE_SESSION_IN_RECOVERY,
1661 FAILURE_SESSION_RECOVERY_TIMEOUT,
1662 FAILURE_SESSION_LOGGING_OUT,
1663 FAILURE_SESSION_NOT_READY,
1664};
1665
1666int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
1667{
1668 struct iscsi_cls_session *cls_session;
1669 struct iscsi_host *ihost;
1670 int reason = 0;
1671 struct iscsi_session *session;
1672 struct iscsi_conn *conn;
1673 struct iscsi_task *task = NULL;
1674
1675 sc->result = 0;
1676 sc->SCp.ptr = NULL;
1677
1678 ihost = shost_priv(host);
1679
1680 cls_session = starget_to_session(scsi_target(sc->device));
1681 session = cls_session->dd_data;
1682 spin_lock_bh(&session->frwd_lock);
1683
1684 reason = iscsi_session_chkready(cls_session);
1685 if (reason) {
1686 sc->result = reason;
1687 goto fault;
1688 }
1689
1690 if (session->state != ISCSI_STATE_LOGGED_IN) {
1691 /*
1692 * to handle the race between when we set the recovery state
1693 * and block the session we requeue here (commands could
1694 * be entering our queuecommand while a block is starting
1695 * up because the block code is not locked)
1696 */
1697 switch (session->state) {
1698 case ISCSI_STATE_FAILED:
1699 /*
1700 * cmds should fail during shutdown, if the session
1701 * state is bad, allowing completion to happen
1702 */
1703 if (unlikely(system_state != SYSTEM_RUNNING)) {
1704 reason = FAILURE_SESSION_FAILED;
1705 sc->result = DID_NO_CONNECT << 16;
1706 break;
1707 }
1708 case ISCSI_STATE_IN_RECOVERY:
1709 reason = FAILURE_SESSION_IN_RECOVERY;
1710 sc->result = DID_IMM_RETRY << 16;
1711 break;
1712 case ISCSI_STATE_LOGGING_OUT:
1713 reason = FAILURE_SESSION_LOGGING_OUT;
1714 sc->result = DID_IMM_RETRY << 16;
1715 break;
1716 case ISCSI_STATE_RECOVERY_FAILED:
1717 reason = FAILURE_SESSION_RECOVERY_TIMEOUT;
1718 sc->result = DID_TRANSPORT_FAILFAST << 16;
1719 break;
1720 case ISCSI_STATE_TERMINATE:
1721 reason = FAILURE_SESSION_TERMINATE;
1722 sc->result = DID_NO_CONNECT << 16;
1723 break;
1724 default:
1725 reason = FAILURE_SESSION_FREED;
1726 sc->result = DID_NO_CONNECT << 16;
1727 }
1728 goto fault;
1729 }
1730
1731 conn = session->leadconn;
1732 if (!conn) {
1733 reason = FAILURE_SESSION_FREED;
1734 sc->result = DID_NO_CONNECT << 16;
1735 goto fault;
1736 }
1737
1738 if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) {
1739 reason = FAILURE_SESSION_IN_RECOVERY;
1740 sc->result = DID_REQUEUE << 16;
1741 goto fault;
1742 }
1743
1744 if (iscsi_check_cmdsn_window_closed(conn)) {
1745 reason = FAILURE_WINDOW_CLOSED;
1746 goto reject;
1747 }
1748
1749 task = iscsi_alloc_task(conn, sc);
1750 if (!task) {
1751 reason = FAILURE_OOM;
1752 goto reject;
1753 }
1754
1755 if (!ihost->workq) {
1756 reason = iscsi_prep_scsi_cmd_pdu(task);
1757 if (reason) {
1758 if (reason == -ENOMEM || reason == -EACCES) {
1759 reason = FAILURE_OOM;
1760 goto prepd_reject;
1761 } else {
1762 sc->result = DID_ABORT << 16;
1763 goto prepd_fault;
1764 }
1765 }
1766 if (session->tt->xmit_task(task)) {
1767 session->cmdsn--;
1768 reason = FAILURE_SESSION_NOT_READY;
1769 goto prepd_reject;
1770 }
1771 } else {
1772 spin_lock_bh(&conn->taskqueuelock);
1773 list_add_tail(&task->running, &conn->cmdqueue);
1774 spin_unlock_bh(&conn->taskqueuelock);
1775 iscsi_conn_queue_work(conn);
1776 }
1777
1778 session->queued_cmdsn++;
1779 spin_unlock_bh(&session->frwd_lock);
1780 return 0;
1781
1782prepd_reject:
1783 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1784reject:
1785 spin_unlock_bh(&session->frwd_lock);
1786 ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
1787 sc->cmnd[0], reason);
1788 return SCSI_MLQUEUE_TARGET_BUSY;
1789
1790prepd_fault:
1791 iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
1792fault:
1793 spin_unlock_bh(&session->frwd_lock);
1794 ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
1795 sc->cmnd[0], reason);
1796 if (!scsi_bidi_cmnd(sc))
1797 scsi_set_resid(sc, scsi_bufflen(sc));
1798 else {
1799 scsi_out(sc)->resid = scsi_out(sc)->length;
1800 scsi_in(sc)->resid = scsi_in(sc)->length;
1801 }
1802 sc->scsi_done(sc);
1803 return 0;
1804}
1805EXPORT_SYMBOL_GPL(iscsi_queuecommand);
1806
1807int iscsi_target_alloc(struct scsi_target *starget)
1808{
1809 struct iscsi_cls_session *cls_session = starget_to_session(starget);
1810 struct iscsi_session *session = cls_session->dd_data;
1811
1812 starget->can_queue = session->scsi_cmds_max;
1813 return 0;
1814}
1815EXPORT_SYMBOL_GPL(iscsi_target_alloc);
1816
1817static void iscsi_tmf_timedout(struct timer_list *t)
1818{
1819 struct iscsi_conn *conn = from_timer(conn, t, tmf_timer);
1820 struct iscsi_session *session = conn->session;
1821
1822 spin_lock(&session->frwd_lock);
1823 if (conn->tmf_state == TMF_QUEUED) {
1824 conn->tmf_state = TMF_TIMEDOUT;
1825 ISCSI_DBG_EH(session, "tmf timedout\n");
1826 /* unblock eh_abort() */
1827 wake_up(&conn->ehwait);
1828 }
1829 spin_unlock(&session->frwd_lock);
1830}
1831
1832static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
1833 struct iscsi_tm *hdr, int age,
1834 int timeout)
1835{
1836 struct iscsi_session *session = conn->session;
1837 struct iscsi_task *task;
1838
1839 task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr,
1840 NULL, 0);
1841 if (!task) {
1842 spin_unlock_bh(&session->frwd_lock);
1843 iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n");
1844 iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
1845 spin_lock_bh(&session->frwd_lock);
1846 return -EPERM;
1847 }
1848 conn->tmfcmd_pdus_cnt++;
1849 conn->tmf_timer.expires = timeout * HZ + jiffies;
1850 add_timer(&conn->tmf_timer);
1851 ISCSI_DBG_EH(session, "tmf set timeout\n");
1852
1853 spin_unlock_bh(&session->frwd_lock);
1854 mutex_unlock(&session->eh_mutex);
1855
1856 /*
1857 * block eh thread until:
1858 *
1859 * 1) tmf response
1860 * 2) tmf timeout
1861 * 3) session is terminated or restarted or userspace has
1862 * given up on recovery
1863 */
1864 wait_event_interruptible(conn->ehwait, age != session->age ||
1865 session->state != ISCSI_STATE_LOGGED_IN ||
1866 conn->tmf_state != TMF_QUEUED);
1867 if (signal_pending(current))
1868 flush_signals(current);
1869 del_timer_sync(&conn->tmf_timer);
1870
1871 mutex_lock(&session->eh_mutex);
1872 spin_lock_bh(&session->frwd_lock);
1873 /* if the session drops it will clean up the task */
1874 if (age != session->age ||
1875 session->state != ISCSI_STATE_LOGGED_IN)
1876 return -ENOTCONN;
1877 return 0;
1878}
1879
1880/*
1881 * Fail commands. session lock held and recv side suspended and xmit
1882 * thread flushed
1883 */
1884static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error)
1885{
1886 struct iscsi_task *task;
1887 int i;
1888
1889 for (i = 0; i < conn->session->cmds_max; i++) {
1890 task = conn->session->cmds[i];
1891 if (!task->sc || task->state == ISCSI_TASK_FREE)
1892 continue;
1893
1894 if (lun != -1 && lun != task->sc->device->lun)
1895 continue;
1896
1897 ISCSI_DBG_SESSION(conn->session,
1898 "failing sc %p itt 0x%x state %d\n",
1899 task->sc, task->itt, task->state);
1900 fail_scsi_task(task, error);
1901 }
1902}
1903
1904/**
1905 * iscsi_suspend_queue - suspend iscsi_queuecommand
1906 * @conn: iscsi conn to stop queueing IO on
1907 *
1908 * This grabs the session frwd_lock to make sure no one is in
1909 * xmit_task/queuecommand, and then sets suspend to prevent
1910 * new commands from being queued. This only needs to be called
1911 * by offload drivers that need to sync a path like ep disconnect
1912 * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi
1913 * will call iscsi_start_tx and iscsi_unblock_session when in FFP.
1914 */
1915void iscsi_suspend_queue(struct iscsi_conn *conn)
1916{
1917 spin_lock_bh(&conn->session->frwd_lock);
1918 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1919 spin_unlock_bh(&conn->session->frwd_lock);
1920}
1921EXPORT_SYMBOL_GPL(iscsi_suspend_queue);
1922
1923/**
1924 * iscsi_suspend_tx - suspend iscsi_data_xmit
1925 * @conn: iscsi conn tp stop processing IO on.
1926 *
1927 * This function sets the suspend bit to prevent iscsi_data_xmit
1928 * from sending new IO, and if work is queued on the xmit thread
1929 * it will wait for it to be completed.
1930 */
1931void iscsi_suspend_tx(struct iscsi_conn *conn)
1932{
1933 struct Scsi_Host *shost = conn->session->host;
1934 struct iscsi_host *ihost = shost_priv(shost);
1935
1936 set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1937 if (ihost->workq)
1938 flush_workqueue(ihost->workq);
1939}
1940EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
1941
1942static void iscsi_start_tx(struct iscsi_conn *conn)
1943{
1944 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
1945 iscsi_conn_queue_work(conn);
1946}
1947
1948/*
1949 * We want to make sure a ping is in flight. It has timed out.
1950 * And we are not busy processing a pdu that is making
1951 * progress but got started before the ping and is taking a while
1952 * to complete so the ping is just stuck behind it in a queue.
1953 */
1954static int iscsi_has_ping_timed_out(struct iscsi_conn *conn)
1955{
1956 if (conn->ping_task &&
1957 time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
1958 (conn->ping_timeout * HZ), jiffies))
1959 return 1;
1960 else
1961 return 0;
1962}
1963
1964enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc)
1965{
1966 enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
1967 struct iscsi_task *task = NULL, *running_task;
1968 struct iscsi_cls_session *cls_session;
1969 struct iscsi_session *session;
1970 struct iscsi_conn *conn;
1971 int i;
1972
1973 cls_session = starget_to_session(scsi_target(sc->device));
1974 session = cls_session->dd_data;
1975
1976 ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc);
1977
1978 spin_lock(&session->frwd_lock);
1979 task = (struct iscsi_task *)sc->SCp.ptr;
1980 if (!task) {
1981 /*
1982 * Raced with completion. Blk layer has taken ownership
1983 * so let timeout code complete it now.
1984 */
1985 rc = BLK_EH_HANDLED;
1986 goto done;
1987 }
1988
1989 if (session->state != ISCSI_STATE_LOGGED_IN) {
1990 /*
1991 * During shutdown, if session is prematurely disconnected,
1992 * recovery won't happen and there will be hung cmds. Not
1993 * handling cmds would trigger EH, also bad in this case.
1994 * Instead, handle cmd, allow completion to happen and let
1995 * upper layer to deal with the result.
1996 */
1997 if (unlikely(system_state != SYSTEM_RUNNING)) {
1998 sc->result = DID_NO_CONNECT << 16;
1999 ISCSI_DBG_EH(session, "sc on shutdown, handled\n");
2000 rc = BLK_EH_HANDLED;
2001 goto done;
2002 }
2003 /*
2004 * We are probably in the middle of iscsi recovery so let
2005 * that complete and handle the error.
2006 */
2007 rc = BLK_EH_RESET_TIMER;
2008 goto done;
2009 }
2010
2011 conn = session->leadconn;
2012 if (!conn) {
2013 /* In the middle of shuting down */
2014 rc = BLK_EH_RESET_TIMER;
2015 goto done;
2016 }
2017
2018 /*
2019 * If we have sent (at least queued to the network layer) a pdu or
2020 * recvd one for the task since the last timeout ask for
2021 * more time. If on the next timeout we have not made progress
2022 * we can check if it is the task or connection when we send the
2023 * nop as a ping.
2024 */
2025 if (time_after(task->last_xfer, task->last_timeout)) {
2026 ISCSI_DBG_EH(session, "Command making progress. Asking "
2027 "scsi-ml for more time to complete. "
2028 "Last data xfer at %lu. Last timeout was at "
2029 "%lu\n.", task->last_xfer, task->last_timeout);
2030 task->have_checked_conn = false;
2031 rc = BLK_EH_RESET_TIMER;
2032 goto done;
2033 }
2034
2035 if (!conn->recv_timeout && !conn->ping_timeout)
2036 goto done;
2037 /*
2038 * if the ping timedout then we are in the middle of cleaning up
2039 * and can let the iscsi eh handle it
2040 */
2041 if (iscsi_has_ping_timed_out(conn)) {
2042 rc = BLK_EH_RESET_TIMER;
2043 goto done;
2044 }
2045
2046 for (i = 0; i < conn->session->cmds_max; i++) {
2047 running_task = conn->session->cmds[i];
2048 if (!running_task->sc || running_task == task ||
2049 running_task->state != ISCSI_TASK_RUNNING)
2050 continue;
2051
2052 /*
2053 * Only check if cmds started before this one have made
2054 * progress, or this could never fail
2055 */
2056 if (time_after(running_task->sc->jiffies_at_alloc,
2057 task->sc->jiffies_at_alloc))
2058 continue;
2059
2060 if (time_after(running_task->last_xfer, task->last_timeout)) {
2061 /*
2062 * This task has not made progress, but a task
2063 * started before us has transferred data since
2064 * we started/last-checked. We could be queueing
2065 * too many tasks or the LU is bad.
2066 *
2067 * If the device is bad the cmds ahead of us on
2068 * other devs will complete, and this loop will
2069 * eventually fail starting the scsi eh.
2070 */
2071 ISCSI_DBG_EH(session, "Command has not made progress "
2072 "but commands ahead of it have. "
2073 "Asking scsi-ml for more time to "
2074 "complete. Our last xfer vs running task "
2075 "last xfer %lu/%lu. Last check %lu.\n",
2076 task->last_xfer, running_task->last_xfer,
2077 task->last_timeout);
2078 rc = BLK_EH_RESET_TIMER;
2079 goto done;
2080 }
2081 }
2082
2083 /* Assumes nop timeout is shorter than scsi cmd timeout */
2084 if (task->have_checked_conn)
2085 goto done;
2086
2087 /*
2088 * Checking the transport already or nop from a cmd timeout still
2089 * running
2090 */
2091 if (conn->ping_task) {
2092 task->have_checked_conn = true;
2093 rc = BLK_EH_RESET_TIMER;
2094 goto done;
2095 }
2096
2097 /* Make sure there is a transport check done */
2098 iscsi_send_nopout(conn, NULL);
2099 task->have_checked_conn = true;
2100 rc = BLK_EH_RESET_TIMER;
2101
2102done:
2103 if (task)
2104 task->last_timeout = jiffies;
2105 spin_unlock(&session->frwd_lock);
2106 ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
2107 "timer reset" : "shutdown or nh");
2108 return rc;
2109}
2110EXPORT_SYMBOL_GPL(iscsi_eh_cmd_timed_out);
2111
2112static void iscsi_check_transport_timeouts(struct timer_list *t)
2113{
2114 struct iscsi_conn *conn = from_timer(conn, t, transport_timer);
2115 struct iscsi_session *session = conn->session;
2116 unsigned long recv_timeout, next_timeout = 0, last_recv;
2117
2118 spin_lock(&session->frwd_lock);
2119 if (session->state != ISCSI_STATE_LOGGED_IN)
2120 goto done;
2121
2122 recv_timeout = conn->recv_timeout;
2123 if (!recv_timeout)
2124 goto done;
2125
2126 recv_timeout *= HZ;
2127 last_recv = conn->last_recv;
2128
2129 if (iscsi_has_ping_timed_out(conn)) {
2130 iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs "
2131 "expired, recv timeout %d, last rx %lu, "
2132 "last ping %lu, now %lu\n",
2133 conn->ping_timeout, conn->recv_timeout,
2134 last_recv, conn->last_ping, jiffies);
2135 spin_unlock(&session->frwd_lock);
2136 iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT);
2137 return;
2138 }
2139
2140 if (time_before_eq(last_recv + recv_timeout, jiffies)) {
2141 /* send a ping to try to provoke some traffic */
2142 ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
2143 if (iscsi_send_nopout(conn, NULL))
2144 next_timeout = jiffies + (1 * HZ);
2145 else
2146 next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
2147 } else
2148 next_timeout = last_recv + recv_timeout;
2149
2150 ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
2151 mod_timer(&conn->transport_timer, next_timeout);
2152done:
2153 spin_unlock(&session->frwd_lock);
2154}
2155
2156static void iscsi_prep_abort_task_pdu(struct iscsi_task *task,
2157 struct iscsi_tm *hdr)
2158{
2159 memset(hdr, 0, sizeof(*hdr));
2160 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2161 hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK;
2162 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2163 hdr->lun = task->lun;
2164 hdr->rtt = task->hdr_itt;
2165 hdr->refcmdsn = task->cmdsn;
2166}
2167
2168int iscsi_eh_abort(struct scsi_cmnd *sc)
2169{
2170 struct iscsi_cls_session *cls_session;
2171 struct iscsi_session *session;
2172 struct iscsi_conn *conn;
2173 struct iscsi_task *task;
2174 struct iscsi_tm *hdr;
2175 int age;
2176
2177 cls_session = starget_to_session(scsi_target(sc->device));
2178 session = cls_session->dd_data;
2179
2180 ISCSI_DBG_EH(session, "aborting sc %p\n", sc);
2181
2182 mutex_lock(&session->eh_mutex);
2183 spin_lock_bh(&session->frwd_lock);
2184 /*
2185 * if session was ISCSI_STATE_IN_RECOVERY then we may not have
2186 * got the command.
2187 */
2188 if (!sc->SCp.ptr) {
2189 ISCSI_DBG_EH(session, "sc never reached iscsi layer or "
2190 "it completed.\n");
2191 spin_unlock_bh(&session->frwd_lock);
2192 mutex_unlock(&session->eh_mutex);
2193 return SUCCESS;
2194 }
2195
2196 /*
2197 * If we are not logged in or we have started a new session
2198 * then let the host reset code handle this
2199 */
2200 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN ||
2201 sc->SCp.phase != session->age) {
2202 spin_unlock_bh(&session->frwd_lock);
2203 mutex_unlock(&session->eh_mutex);
2204 ISCSI_DBG_EH(session, "failing abort due to dropped "
2205 "session.\n");
2206 return FAILED;
2207 }
2208
2209 conn = session->leadconn;
2210 conn->eh_abort_cnt++;
2211 age = session->age;
2212
2213 task = (struct iscsi_task *)sc->SCp.ptr;
2214 ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n",
2215 sc, task->itt);
2216
2217 /* task completed before time out */
2218 if (!task->sc) {
2219 ISCSI_DBG_EH(session, "sc completed while abort in progress\n");
2220 goto success;
2221 }
2222
2223 if (task->state == ISCSI_TASK_PENDING) {
2224 fail_scsi_task(task, DID_ABORT);
2225 goto success;
2226 }
2227
2228 /* only have one tmf outstanding at a time */
2229 if (conn->tmf_state != TMF_INITIAL)
2230 goto failed;
2231 conn->tmf_state = TMF_QUEUED;
2232
2233 hdr = &conn->tmhdr;
2234 iscsi_prep_abort_task_pdu(task, hdr);
2235
2236 if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout))
2237 goto failed;
2238
2239 switch (conn->tmf_state) {
2240 case TMF_SUCCESS:
2241 spin_unlock_bh(&session->frwd_lock);
2242 /*
2243 * stop tx side incase the target had sent a abort rsp but
2244 * the initiator was still writing out data.
2245 */
2246 iscsi_suspend_tx(conn);
2247 /*
2248 * we do not stop the recv side because targets have been
2249 * good and have never sent us a successful tmf response
2250 * then sent more data for the cmd.
2251 */
2252 spin_lock_bh(&session->frwd_lock);
2253 fail_scsi_task(task, DID_ABORT);
2254 conn->tmf_state = TMF_INITIAL;
2255 memset(hdr, 0, sizeof(*hdr));
2256 spin_unlock_bh(&session->frwd_lock);
2257 iscsi_start_tx(conn);
2258 goto success_unlocked;
2259 case TMF_TIMEDOUT:
2260 spin_unlock_bh(&session->frwd_lock);
2261 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2262 goto failed_unlocked;
2263 case TMF_NOT_FOUND:
2264 if (!sc->SCp.ptr) {
2265 conn->tmf_state = TMF_INITIAL;
2266 memset(hdr, 0, sizeof(*hdr));
2267 /* task completed before tmf abort response */
2268 ISCSI_DBG_EH(session, "sc completed while abort in "
2269 "progress\n");
2270 goto success;
2271 }
2272 /* fall through */
2273 default:
2274 conn->tmf_state = TMF_INITIAL;
2275 goto failed;
2276 }
2277
2278success:
2279 spin_unlock_bh(&session->frwd_lock);
2280success_unlocked:
2281 ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n",
2282 sc, task->itt);
2283 mutex_unlock(&session->eh_mutex);
2284 return SUCCESS;
2285
2286failed:
2287 spin_unlock_bh(&session->frwd_lock);
2288failed_unlocked:
2289 ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc,
2290 task ? task->itt : 0);
2291 mutex_unlock(&session->eh_mutex);
2292 return FAILED;
2293}
2294EXPORT_SYMBOL_GPL(iscsi_eh_abort);
2295
2296static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2297{
2298 memset(hdr, 0, sizeof(*hdr));
2299 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2300 hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2301 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2302 int_to_scsilun(sc->device->lun, &hdr->lun);
2303 hdr->rtt = RESERVED_ITT;
2304}
2305
2306int iscsi_eh_device_reset(struct scsi_cmnd *sc)
2307{
2308 struct iscsi_cls_session *cls_session;
2309 struct iscsi_session *session;
2310 struct iscsi_conn *conn;
2311 struct iscsi_tm *hdr;
2312 int rc = FAILED;
2313
2314 cls_session = starget_to_session(scsi_target(sc->device));
2315 session = cls_session->dd_data;
2316
2317 ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc,
2318 sc->device->lun);
2319
2320 mutex_lock(&session->eh_mutex);
2321 spin_lock_bh(&session->frwd_lock);
2322 /*
2323 * Just check if we are not logged in. We cannot check for
2324 * the phase because the reset could come from a ioctl.
2325 */
2326 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2327 goto unlock;
2328 conn = session->leadconn;
2329
2330 /* only have one tmf outstanding at a time */
2331 if (conn->tmf_state != TMF_INITIAL)
2332 goto unlock;
2333 conn->tmf_state = TMF_QUEUED;
2334
2335 hdr = &conn->tmhdr;
2336 iscsi_prep_lun_reset_pdu(sc, hdr);
2337
2338 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2339 session->lu_reset_timeout)) {
2340 rc = FAILED;
2341 goto unlock;
2342 }
2343
2344 switch (conn->tmf_state) {
2345 case TMF_SUCCESS:
2346 break;
2347 case TMF_TIMEDOUT:
2348 spin_unlock_bh(&session->frwd_lock);
2349 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2350 goto done;
2351 default:
2352 conn->tmf_state = TMF_INITIAL;
2353 goto unlock;
2354 }
2355
2356 rc = SUCCESS;
2357 spin_unlock_bh(&session->frwd_lock);
2358
2359 iscsi_suspend_tx(conn);
2360
2361 spin_lock_bh(&session->frwd_lock);
2362 memset(hdr, 0, sizeof(*hdr));
2363 fail_scsi_tasks(conn, sc->device->lun, DID_ERROR);
2364 conn->tmf_state = TMF_INITIAL;
2365 spin_unlock_bh(&session->frwd_lock);
2366
2367 iscsi_start_tx(conn);
2368 goto done;
2369
2370unlock:
2371 spin_unlock_bh(&session->frwd_lock);
2372done:
2373 ISCSI_DBG_EH(session, "dev reset result = %s\n",
2374 rc == SUCCESS ? "SUCCESS" : "FAILED");
2375 mutex_unlock(&session->eh_mutex);
2376 return rc;
2377}
2378EXPORT_SYMBOL_GPL(iscsi_eh_device_reset);
2379
2380void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session)
2381{
2382 struct iscsi_session *session = cls_session->dd_data;
2383
2384 spin_lock_bh(&session->frwd_lock);
2385 if (session->state != ISCSI_STATE_LOGGED_IN) {
2386 session->state = ISCSI_STATE_RECOVERY_FAILED;
2387 if (session->leadconn)
2388 wake_up(&session->leadconn->ehwait);
2389 }
2390 spin_unlock_bh(&session->frwd_lock);
2391}
2392EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout);
2393
2394/**
2395 * iscsi_eh_session_reset - drop session and attempt relogin
2396 * @sc: scsi command
2397 *
2398 * This function will wait for a relogin, session termination from
2399 * userspace, or a recovery/replacement timeout.
2400 */
2401int iscsi_eh_session_reset(struct scsi_cmnd *sc)
2402{
2403 struct iscsi_cls_session *cls_session;
2404 struct iscsi_session *session;
2405 struct iscsi_conn *conn;
2406
2407 cls_session = starget_to_session(scsi_target(sc->device));
2408 session = cls_session->dd_data;
2409 conn = session->leadconn;
2410
2411 mutex_lock(&session->eh_mutex);
2412 spin_lock_bh(&session->frwd_lock);
2413 if (session->state == ISCSI_STATE_TERMINATE) {
2414failed:
2415 ISCSI_DBG_EH(session,
2416 "failing session reset: Could not log back into "
2417 "%s, %s [age %d]\n", session->targetname,
2418 conn->persistent_address, session->age);
2419 spin_unlock_bh(&session->frwd_lock);
2420 mutex_unlock(&session->eh_mutex);
2421 return FAILED;
2422 }
2423
2424 spin_unlock_bh(&session->frwd_lock);
2425 mutex_unlock(&session->eh_mutex);
2426 /*
2427 * we drop the lock here but the leadconn cannot be destoyed while
2428 * we are in the scsi eh
2429 */
2430 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2431
2432 ISCSI_DBG_EH(session, "wait for relogin\n");
2433 wait_event_interruptible(conn->ehwait,
2434 session->state == ISCSI_STATE_TERMINATE ||
2435 session->state == ISCSI_STATE_LOGGED_IN ||
2436 session->state == ISCSI_STATE_RECOVERY_FAILED);
2437 if (signal_pending(current))
2438 flush_signals(current);
2439
2440 mutex_lock(&session->eh_mutex);
2441 spin_lock_bh(&session->frwd_lock);
2442 if (session->state == ISCSI_STATE_LOGGED_IN) {
2443 ISCSI_DBG_EH(session,
2444 "session reset succeeded for %s,%s\n",
2445 session->targetname, conn->persistent_address);
2446 } else
2447 goto failed;
2448 spin_unlock_bh(&session->frwd_lock);
2449 mutex_unlock(&session->eh_mutex);
2450 return SUCCESS;
2451}
2452EXPORT_SYMBOL_GPL(iscsi_eh_session_reset);
2453
2454static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr)
2455{
2456 memset(hdr, 0, sizeof(*hdr));
2457 hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
2458 hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK;
2459 hdr->flags |= ISCSI_FLAG_CMD_FINAL;
2460 hdr->rtt = RESERVED_ITT;
2461}
2462
2463/**
2464 * iscsi_eh_target_reset - reset target
2465 * @sc: scsi command
2466 *
2467 * This will attempt to send a warm target reset.
2468 */
2469static int iscsi_eh_target_reset(struct scsi_cmnd *sc)
2470{
2471 struct iscsi_cls_session *cls_session;
2472 struct iscsi_session *session;
2473 struct iscsi_conn *conn;
2474 struct iscsi_tm *hdr;
2475 int rc = FAILED;
2476
2477 cls_session = starget_to_session(scsi_target(sc->device));
2478 session = cls_session->dd_data;
2479
2480 ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc,
2481 session->targetname);
2482
2483 mutex_lock(&session->eh_mutex);
2484 spin_lock_bh(&session->frwd_lock);
2485 /*
2486 * Just check if we are not logged in. We cannot check for
2487 * the phase because the reset could come from a ioctl.
2488 */
2489 if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN)
2490 goto unlock;
2491 conn = session->leadconn;
2492
2493 /* only have one tmf outstanding at a time */
2494 if (conn->tmf_state != TMF_INITIAL)
2495 goto unlock;
2496 conn->tmf_state = TMF_QUEUED;
2497
2498 hdr = &conn->tmhdr;
2499 iscsi_prep_tgt_reset_pdu(sc, hdr);
2500
2501 if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age,
2502 session->tgt_reset_timeout)) {
2503 rc = FAILED;
2504 goto unlock;
2505 }
2506
2507 switch (conn->tmf_state) {
2508 case TMF_SUCCESS:
2509 break;
2510 case TMF_TIMEDOUT:
2511 spin_unlock_bh(&session->frwd_lock);
2512 iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST);
2513 goto done;
2514 default:
2515 conn->tmf_state = TMF_INITIAL;
2516 goto unlock;
2517 }
2518
2519 rc = SUCCESS;
2520 spin_unlock_bh(&session->frwd_lock);
2521
2522 iscsi_suspend_tx(conn);
2523
2524 spin_lock_bh(&session->frwd_lock);
2525 memset(hdr, 0, sizeof(*hdr));
2526 fail_scsi_tasks(conn, -1, DID_ERROR);
2527 conn->tmf_state = TMF_INITIAL;
2528 spin_unlock_bh(&session->frwd_lock);
2529
2530 iscsi_start_tx(conn);
2531 goto done;
2532
2533unlock:
2534 spin_unlock_bh(&session->frwd_lock);
2535done:
2536 ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname,
2537 rc == SUCCESS ? "SUCCESS" : "FAILED");
2538 mutex_unlock(&session->eh_mutex);
2539 return rc;
2540}
2541
2542/**
2543 * iscsi_eh_recover_target - reset target and possibly the session
2544 * @sc: scsi command
2545 *
2546 * This will attempt to send a warm target reset. If that fails,
2547 * we will escalate to ERL0 session recovery.
2548 */
2549int iscsi_eh_recover_target(struct scsi_cmnd *sc)
2550{
2551 int rc;
2552
2553 rc = iscsi_eh_target_reset(sc);
2554 if (rc == FAILED)
2555 rc = iscsi_eh_session_reset(sc);
2556 return rc;
2557}
2558EXPORT_SYMBOL_GPL(iscsi_eh_recover_target);
2559
2560/*
2561 * Pre-allocate a pool of @max items of @item_size. By default, the pool
2562 * should be accessed via kfifo_{get,put} on q->queue.
2563 * Optionally, the caller can obtain the array of object pointers
2564 * by passing in a non-NULL @items pointer
2565 */
2566int
2567iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
2568{
2569 int i, num_arrays = 1;
2570
2571 memset(q, 0, sizeof(*q));
2572
2573 q->max = max;
2574
2575 /* If the user passed an items pointer, he wants a copy of
2576 * the array. */
2577 if (items)
2578 num_arrays++;
2579 q->pool = kvzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
2580 if (q->pool == NULL)
2581 return -ENOMEM;
2582
2583 kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*));
2584
2585 for (i = 0; i < max; i++) {
2586 q->pool[i] = kzalloc(item_size, GFP_KERNEL);
2587 if (q->pool[i] == NULL) {
2588 q->max = i;
2589 goto enomem;
2590 }
2591 kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*));
2592 }
2593
2594 if (items) {
2595 *items = q->pool + max;
2596 memcpy(*items, q->pool, max * sizeof(void *));
2597 }
2598
2599 return 0;
2600
2601enomem:
2602 iscsi_pool_free(q);
2603 return -ENOMEM;
2604}
2605EXPORT_SYMBOL_GPL(iscsi_pool_init);
2606
2607void iscsi_pool_free(struct iscsi_pool *q)
2608{
2609 int i;
2610
2611 for (i = 0; i < q->max; i++)
2612 kfree(q->pool[i]);
2613 kvfree(q->pool);
2614}
2615EXPORT_SYMBOL_GPL(iscsi_pool_free);
2616
2617/**
2618 * iscsi_host_add - add host to system
2619 * @shost: scsi host
2620 * @pdev: parent device
2621 *
2622 * This should be called by partial offload and software iscsi drivers
2623 * to add a host to the system.
2624 */
2625int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
2626{
2627 if (!shost->can_queue)
2628 shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
2629
2630 if (!shost->cmd_per_lun)
2631 shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
2632
2633 return scsi_add_host(shost, pdev);
2634}
2635EXPORT_SYMBOL_GPL(iscsi_host_add);
2636
2637/**
2638 * iscsi_host_alloc - allocate a host and driver data
2639 * @sht: scsi host template
2640 * @dd_data_size: driver host data size
2641 * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
2642 *
2643 * This should be called by partial offload and software iscsi drivers.
2644 * To access the driver specific memory use the iscsi_host_priv() macro.
2645 */
2646struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
2647 int dd_data_size, bool xmit_can_sleep)
2648{
2649 struct Scsi_Host *shost;
2650 struct iscsi_host *ihost;
2651
2652 shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
2653 if (!shost)
2654 return NULL;
2655 ihost = shost_priv(shost);
2656
2657 if (xmit_can_sleep) {
2658 snprintf(ihost->workq_name, sizeof(ihost->workq_name),
2659 "iscsi_q_%d", shost->host_no);
2660 ihost->workq = create_singlethread_workqueue(ihost->workq_name);
2661 if (!ihost->workq)
2662 goto free_host;
2663 }
2664
2665 spin_lock_init(&ihost->lock);
2666 ihost->state = ISCSI_HOST_SETUP;
2667 ihost->num_sessions = 0;
2668 init_waitqueue_head(&ihost->session_removal_wq);
2669 return shost;
2670
2671free_host:
2672 scsi_host_put(shost);
2673 return NULL;
2674}
2675EXPORT_SYMBOL_GPL(iscsi_host_alloc);
2676
2677static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
2678{
2679 iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
2680}
2681
2682/**
2683 * iscsi_host_remove - remove host and sessions
2684 * @shost: scsi host
2685 *
2686 * If there are any sessions left, this will initiate the removal and wait
2687 * for the completion.
2688 */
2689void iscsi_host_remove(struct Scsi_Host *shost)
2690{
2691 struct iscsi_host *ihost = shost_priv(shost);
2692 unsigned long flags;
2693
2694 spin_lock_irqsave(&ihost->lock, flags);
2695 ihost->state = ISCSI_HOST_REMOVED;
2696 spin_unlock_irqrestore(&ihost->lock, flags);
2697
2698 iscsi_host_for_each_session(shost, iscsi_notify_host_removed);
2699 wait_event_interruptible(ihost->session_removal_wq,
2700 ihost->num_sessions == 0);
2701 if (signal_pending(current))
2702 flush_signals(current);
2703
2704 scsi_remove_host(shost);
2705 if (ihost->workq)
2706 destroy_workqueue(ihost->workq);
2707}
2708EXPORT_SYMBOL_GPL(iscsi_host_remove);
2709
2710void iscsi_host_free(struct Scsi_Host *shost)
2711{
2712 struct iscsi_host *ihost = shost_priv(shost);
2713
2714 kfree(ihost->netdev);
2715 kfree(ihost->hwaddress);
2716 kfree(ihost->initiatorname);
2717 scsi_host_put(shost);
2718}
2719EXPORT_SYMBOL_GPL(iscsi_host_free);
2720
2721static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost)
2722{
2723 struct iscsi_host *ihost = shost_priv(shost);
2724 unsigned long flags;
2725
2726 shost = scsi_host_get(shost);
2727 if (!shost) {
2728 printk(KERN_ERR "Invalid state. Cannot notify host removal "
2729 "of session teardown event because host already "
2730 "removed.\n");
2731 return;
2732 }
2733
2734 spin_lock_irqsave(&ihost->lock, flags);
2735 ihost->num_sessions--;
2736 if (ihost->num_sessions == 0)
2737 wake_up(&ihost->session_removal_wq);
2738 spin_unlock_irqrestore(&ihost->lock, flags);
2739 scsi_host_put(shost);
2740}
2741
2742/**
2743 * iscsi_session_setup - create iscsi cls session and host and session
2744 * @iscsit: iscsi transport template
2745 * @shost: scsi host
2746 * @cmds_max: session can queue
2747 * @dd_size: private driver data size, added to session allocation size
2748 * @cmd_task_size: LLD task private data size
2749 * @initial_cmdsn: initial CmdSN
2750 * @id: target ID to add to this session
2751 *
2752 * This can be used by software iscsi_transports that allocate
2753 * a session per scsi host.
2754 *
2755 * Callers should set cmds_max to the largest total numer (mgmt + scsi) of
2756 * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks
2757 * for nop handling and login/logout requests.
2758 */
2759struct iscsi_cls_session *
2760iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost,
2761 uint16_t cmds_max, int dd_size, int cmd_task_size,
2762 uint32_t initial_cmdsn, unsigned int id)
2763{
2764 struct iscsi_host *ihost = shost_priv(shost);
2765 struct iscsi_session *session;
2766 struct iscsi_cls_session *cls_session;
2767 int cmd_i, scsi_cmds, total_cmds = cmds_max;
2768 unsigned long flags;
2769
2770 spin_lock_irqsave(&ihost->lock, flags);
2771 if (ihost->state == ISCSI_HOST_REMOVED) {
2772 spin_unlock_irqrestore(&ihost->lock, flags);
2773 return NULL;
2774 }
2775 ihost->num_sessions++;
2776 spin_unlock_irqrestore(&ihost->lock, flags);
2777
2778 if (!total_cmds)
2779 total_cmds = ISCSI_DEF_XMIT_CMDS_MAX;
2780 /*
2781 * The iscsi layer needs some tasks for nop handling and tmfs,
2782 * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX
2783 * + 1 command for scsi IO.
2784 */
2785 if (total_cmds < ISCSI_TOTAL_CMDS_MIN) {
2786 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2787 "must be a power of two that is at least %d.\n",
2788 total_cmds, ISCSI_TOTAL_CMDS_MIN);
2789 goto dec_session_count;
2790 }
2791
2792 if (total_cmds > ISCSI_TOTAL_CMDS_MAX) {
2793 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2794 "must be a power of 2 less than or equal to %d.\n",
2795 cmds_max, ISCSI_TOTAL_CMDS_MAX);
2796 total_cmds = ISCSI_TOTAL_CMDS_MAX;
2797 }
2798
2799 if (!is_power_of_2(total_cmds)) {
2800 printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue "
2801 "must be a power of 2.\n", total_cmds);
2802 total_cmds = rounddown_pow_of_two(total_cmds);
2803 if (total_cmds < ISCSI_TOTAL_CMDS_MIN)
2804 return NULL;
2805 printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n",
2806 total_cmds);
2807 }
2808 scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX;
2809
2810 cls_session = iscsi_alloc_session(shost, iscsit,
2811 sizeof(struct iscsi_session) +
2812 dd_size);
2813 if (!cls_session)
2814 goto dec_session_count;
2815 session = cls_session->dd_data;
2816 session->cls_session = cls_session;
2817 session->host = shost;
2818 session->state = ISCSI_STATE_FREE;
2819 session->fast_abort = 1;
2820 session->tgt_reset_timeout = 30;
2821 session->lu_reset_timeout = 15;
2822 session->abort_timeout = 10;
2823 session->scsi_cmds_max = scsi_cmds;
2824 session->cmds_max = total_cmds;
2825 session->queued_cmdsn = session->cmdsn = initial_cmdsn;
2826 session->exp_cmdsn = initial_cmdsn + 1;
2827 session->max_cmdsn = initial_cmdsn + 1;
2828 session->max_r2t = 1;
2829 session->tt = iscsit;
2830 session->dd_data = cls_session->dd_data + sizeof(*session);
2831
2832 mutex_init(&session->eh_mutex);
2833 spin_lock_init(&session->frwd_lock);
2834 spin_lock_init(&session->back_lock);
2835
2836 /* initialize SCSI PDU commands pool */
2837 if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
2838 (void***)&session->cmds,
2839 cmd_task_size + sizeof(struct iscsi_task)))
2840 goto cmdpool_alloc_fail;
2841
2842 /* pre-format cmds pool with ITT */
2843 for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
2844 struct iscsi_task *task = session->cmds[cmd_i];
2845
2846 if (cmd_task_size)
2847 task->dd_data = &task[1];
2848 task->itt = cmd_i;
2849 task->state = ISCSI_TASK_FREE;
2850 INIT_LIST_HEAD(&task->running);
2851 }
2852
2853 if (!try_module_get(iscsit->owner))
2854 goto module_get_fail;
2855
2856 if (iscsi_add_session(cls_session, id))
2857 goto cls_session_fail;
2858
2859 return cls_session;
2860
2861cls_session_fail:
2862 module_put(iscsit->owner);
2863module_get_fail:
2864 iscsi_pool_free(&session->cmdpool);
2865cmdpool_alloc_fail:
2866 iscsi_free_session(cls_session);
2867dec_session_count:
2868 iscsi_host_dec_session_cnt(shost);
2869 return NULL;
2870}
2871EXPORT_SYMBOL_GPL(iscsi_session_setup);
2872
2873/**
2874 * iscsi_session_teardown - destroy session, host, and cls_session
2875 * @cls_session: iscsi session
2876 */
2877void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
2878{
2879 struct iscsi_session *session = cls_session->dd_data;
2880 struct module *owner = cls_session->transport->owner;
2881 struct Scsi_Host *shost = session->host;
2882
2883 iscsi_pool_free(&session->cmdpool);
2884
2885 iscsi_remove_session(cls_session);
2886
2887 kfree(session->password);
2888 kfree(session->password_in);
2889 kfree(session->username);
2890 kfree(session->username_in);
2891 kfree(session->targetname);
2892 kfree(session->targetalias);
2893 kfree(session->initiatorname);
2894 kfree(session->boot_root);
2895 kfree(session->boot_nic);
2896 kfree(session->boot_target);
2897 kfree(session->ifacename);
2898 kfree(session->portal_type);
2899 kfree(session->discovery_parent_type);
2900
2901 iscsi_free_session(cls_session);
2902
2903 iscsi_host_dec_session_cnt(shost);
2904 module_put(owner);
2905}
2906EXPORT_SYMBOL_GPL(iscsi_session_teardown);
2907
2908/**
2909 * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn
2910 * @cls_session: iscsi_cls_session
2911 * @dd_size: private driver data size
2912 * @conn_idx: cid
2913 */
2914struct iscsi_cls_conn *
2915iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size,
2916 uint32_t conn_idx)
2917{
2918 struct iscsi_session *session = cls_session->dd_data;
2919 struct iscsi_conn *conn;
2920 struct iscsi_cls_conn *cls_conn;
2921 char *data;
2922
2923 cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size,
2924 conn_idx);
2925 if (!cls_conn)
2926 return NULL;
2927 conn = cls_conn->dd_data;
2928 memset(conn, 0, sizeof(*conn) + dd_size);
2929
2930 conn->dd_data = cls_conn->dd_data + sizeof(*conn);
2931 conn->session = session;
2932 conn->cls_conn = cls_conn;
2933 conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
2934 conn->id = conn_idx;
2935 conn->exp_statsn = 0;
2936 conn->tmf_state = TMF_INITIAL;
2937
2938 timer_setup(&conn->transport_timer, iscsi_check_transport_timeouts, 0);
2939
2940 INIT_LIST_HEAD(&conn->mgmtqueue);
2941 INIT_LIST_HEAD(&conn->cmdqueue);
2942 INIT_LIST_HEAD(&conn->requeue);
2943 spin_lock_init(&conn->taskqueuelock);
2944 INIT_WORK(&conn->xmitwork, iscsi_xmitworker);
2945
2946 /* allocate login_task used for the login/text sequences */
2947 spin_lock_bh(&session->frwd_lock);
2948 if (!kfifo_out(&session->cmdpool.queue,
2949 (void*)&conn->login_task,
2950 sizeof(void*))) {
2951 spin_unlock_bh(&session->frwd_lock);
2952 goto login_task_alloc_fail;
2953 }
2954 spin_unlock_bh(&session->frwd_lock);
2955
2956 data = (char *) __get_free_pages(GFP_KERNEL,
2957 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
2958 if (!data)
2959 goto login_task_data_alloc_fail;
2960 conn->login_task->data = conn->data = data;
2961
2962 timer_setup(&conn->tmf_timer, iscsi_tmf_timedout, 0);
2963 init_waitqueue_head(&conn->ehwait);
2964
2965 return cls_conn;
2966
2967login_task_data_alloc_fail:
2968 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
2969 sizeof(void*));
2970login_task_alloc_fail:
2971 iscsi_destroy_conn(cls_conn);
2972 return NULL;
2973}
2974EXPORT_SYMBOL_GPL(iscsi_conn_setup);
2975
2976/**
2977 * iscsi_conn_teardown - teardown iscsi connection
2978 * @cls_conn: iscsi class connection
2979 *
2980 * TODO: we may need to make this into a two step process
2981 * like scsi-mls remove + put host
2982 */
2983void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
2984{
2985 struct iscsi_conn *conn = cls_conn->dd_data;
2986 struct iscsi_session *session = conn->session;
2987
2988 del_timer_sync(&conn->transport_timer);
2989
2990 mutex_lock(&session->eh_mutex);
2991 spin_lock_bh(&session->frwd_lock);
2992 conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
2993 if (session->leadconn == conn) {
2994 /*
2995 * leading connection? then give up on recovery.
2996 */
2997 session->state = ISCSI_STATE_TERMINATE;
2998 wake_up(&conn->ehwait);
2999 }
3000 spin_unlock_bh(&session->frwd_lock);
3001
3002 /* flush queued up work because we free the connection below */
3003 iscsi_suspend_tx(conn);
3004
3005 spin_lock_bh(&session->frwd_lock);
3006 free_pages((unsigned long) conn->data,
3007 get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
3008 kfree(conn->persistent_address);
3009 kfree(conn->local_ipaddr);
3010 /* regular RX path uses back_lock */
3011 spin_lock_bh(&session->back_lock);
3012 kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
3013 sizeof(void*));
3014 spin_unlock_bh(&session->back_lock);
3015 if (session->leadconn == conn)
3016 session->leadconn = NULL;
3017 spin_unlock_bh(&session->frwd_lock);
3018 mutex_unlock(&session->eh_mutex);
3019
3020 iscsi_destroy_conn(cls_conn);
3021}
3022EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
3023
3024int iscsi_conn_start(struct iscsi_cls_conn *cls_conn)
3025{
3026 struct iscsi_conn *conn = cls_conn->dd_data;
3027 struct iscsi_session *session = conn->session;
3028
3029 if (!session) {
3030 iscsi_conn_printk(KERN_ERR, conn,
3031 "can't start unbound connection\n");
3032 return -EPERM;
3033 }
3034
3035 if ((session->imm_data_en || !session->initial_r2t_en) &&
3036 session->first_burst > session->max_burst) {
3037 iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: "
3038 "first_burst %d max_burst %d\n",
3039 session->first_burst, session->max_burst);
3040 return -EINVAL;
3041 }
3042
3043 if (conn->ping_timeout && !conn->recv_timeout) {
3044 iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of "
3045 "zero. Using 5 seconds\n.");
3046 conn->recv_timeout = 5;
3047 }
3048
3049 if (conn->recv_timeout && !conn->ping_timeout) {
3050 iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of "
3051 "zero. Using 5 seconds.\n");
3052 conn->ping_timeout = 5;
3053 }
3054
3055 spin_lock_bh(&session->frwd_lock);
3056 conn->c_stage = ISCSI_CONN_STARTED;
3057 session->state = ISCSI_STATE_LOGGED_IN;
3058 session->queued_cmdsn = session->cmdsn;
3059
3060 conn->last_recv = jiffies;
3061 conn->last_ping = jiffies;
3062 if (conn->recv_timeout && conn->ping_timeout)
3063 mod_timer(&conn->transport_timer,
3064 jiffies + (conn->recv_timeout * HZ));
3065
3066 switch(conn->stop_stage) {
3067 case STOP_CONN_RECOVER:
3068 /*
3069 * unblock eh_abort() if it is blocked. re-try all
3070 * commands after successful recovery
3071 */
3072 conn->stop_stage = 0;
3073 conn->tmf_state = TMF_INITIAL;
3074 session->age++;
3075 if (session->age == 16)
3076 session->age = 0;
3077 break;
3078 case STOP_CONN_TERM:
3079 conn->stop_stage = 0;
3080 break;
3081 default:
3082 break;
3083 }
3084 spin_unlock_bh(&session->frwd_lock);
3085
3086 iscsi_unblock_session(session->cls_session);
3087 wake_up(&conn->ehwait);
3088 return 0;
3089}
3090EXPORT_SYMBOL_GPL(iscsi_conn_start);
3091
3092static void
3093fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn)
3094{
3095 struct iscsi_task *task;
3096 int i, state;
3097
3098 for (i = 0; i < conn->session->cmds_max; i++) {
3099 task = conn->session->cmds[i];
3100 if (task->sc)
3101 continue;
3102
3103 if (task->state == ISCSI_TASK_FREE)
3104 continue;
3105
3106 ISCSI_DBG_SESSION(conn->session,
3107 "failing mgmt itt 0x%x state %d\n",
3108 task->itt, task->state);
3109 state = ISCSI_TASK_ABRT_SESS_RECOV;
3110 if (task->state == ISCSI_TASK_PENDING)
3111 state = ISCSI_TASK_COMPLETED;
3112 iscsi_complete_task(task, state);
3113
3114 }
3115}
3116
3117static void iscsi_start_session_recovery(struct iscsi_session *session,
3118 struct iscsi_conn *conn, int flag)
3119{
3120 int old_stop_stage;
3121
3122 mutex_lock(&session->eh_mutex);
3123 spin_lock_bh(&session->frwd_lock);
3124 if (conn->stop_stage == STOP_CONN_TERM) {
3125 spin_unlock_bh(&session->frwd_lock);
3126 mutex_unlock(&session->eh_mutex);
3127 return;
3128 }
3129
3130 /*
3131 * When this is called for the in_login state, we only want to clean
3132 * up the login task and connection. We do not need to block and set
3133 * the recovery state again
3134 */
3135 if (flag == STOP_CONN_TERM)
3136 session->state = ISCSI_STATE_TERMINATE;
3137 else if (conn->stop_stage != STOP_CONN_RECOVER)
3138 session->state = ISCSI_STATE_IN_RECOVERY;
3139
3140 old_stop_stage = conn->stop_stage;
3141 conn->stop_stage = flag;
3142 spin_unlock_bh(&session->frwd_lock);
3143
3144 del_timer_sync(&conn->transport_timer);
3145 iscsi_suspend_tx(conn);
3146
3147 spin_lock_bh(&session->frwd_lock);
3148 conn->c_stage = ISCSI_CONN_STOPPED;
3149 spin_unlock_bh(&session->frwd_lock);
3150
3151 /*
3152 * for connection level recovery we should not calculate
3153 * header digest. conn->hdr_size used for optimization
3154 * in hdr_extract() and will be re-negotiated at
3155 * set_param() time.
3156 */
3157 if (flag == STOP_CONN_RECOVER) {
3158 conn->hdrdgst_en = 0;
3159 conn->datadgst_en = 0;
3160 if (session->state == ISCSI_STATE_IN_RECOVERY &&
3161 old_stop_stage != STOP_CONN_RECOVER) {
3162 ISCSI_DBG_SESSION(session, "blocking session\n");
3163 iscsi_block_session(session->cls_session);
3164 }
3165 }
3166
3167 /*
3168 * flush queues.
3169 */
3170 spin_lock_bh(&session->frwd_lock);
3171 fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED);
3172 fail_mgmt_tasks(session, conn);
3173 memset(&conn->tmhdr, 0, sizeof(conn->tmhdr));
3174 spin_unlock_bh(&session->frwd_lock);
3175 mutex_unlock(&session->eh_mutex);
3176}
3177
3178void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
3179{
3180 struct iscsi_conn *conn = cls_conn->dd_data;
3181 struct iscsi_session *session = conn->session;
3182
3183 switch (flag) {
3184 case STOP_CONN_RECOVER:
3185 case STOP_CONN_TERM:
3186 iscsi_start_session_recovery(session, conn, flag);
3187 break;
3188 default:
3189 iscsi_conn_printk(KERN_ERR, conn,
3190 "invalid stop flag %d\n", flag);
3191 }
3192}
3193EXPORT_SYMBOL_GPL(iscsi_conn_stop);
3194
3195int iscsi_conn_bind(struct iscsi_cls_session *cls_session,
3196 struct iscsi_cls_conn *cls_conn, int is_leading)
3197{
3198 struct iscsi_session *session = cls_session->dd_data;
3199 struct iscsi_conn *conn = cls_conn->dd_data;
3200
3201 spin_lock_bh(&session->frwd_lock);
3202 if (is_leading)
3203 session->leadconn = conn;
3204 spin_unlock_bh(&session->frwd_lock);
3205
3206 /*
3207 * Unblock xmitworker(), Login Phase will pass through.
3208 */
3209 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
3210 clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
3211 return 0;
3212}
3213EXPORT_SYMBOL_GPL(iscsi_conn_bind);
3214
3215int iscsi_switch_str_param(char **param, char *new_val_buf)
3216{
3217 char *new_val;
3218
3219 if (*param) {
3220 if (!strcmp(*param, new_val_buf))
3221 return 0;
3222 }
3223
3224 new_val = kstrdup(new_val_buf, GFP_NOIO);
3225 if (!new_val)
3226 return -ENOMEM;
3227
3228 kfree(*param);
3229 *param = new_val;
3230 return 0;
3231}
3232EXPORT_SYMBOL_GPL(iscsi_switch_str_param);
3233
3234int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
3235 enum iscsi_param param, char *buf, int buflen)
3236{
3237 struct iscsi_conn *conn = cls_conn->dd_data;
3238 struct iscsi_session *session = conn->session;
3239 int val;
3240
3241 switch(param) {
3242 case ISCSI_PARAM_FAST_ABORT:
3243 sscanf(buf, "%d", &session->fast_abort);
3244 break;
3245 case ISCSI_PARAM_ABORT_TMO:
3246 sscanf(buf, "%d", &session->abort_timeout);
3247 break;
3248 case ISCSI_PARAM_LU_RESET_TMO:
3249 sscanf(buf, "%d", &session->lu_reset_timeout);
3250 break;
3251 case ISCSI_PARAM_TGT_RESET_TMO:
3252 sscanf(buf, "%d", &session->tgt_reset_timeout);
3253 break;
3254 case ISCSI_PARAM_PING_TMO:
3255 sscanf(buf, "%d", &conn->ping_timeout);
3256 break;
3257 case ISCSI_PARAM_RECV_TMO:
3258 sscanf(buf, "%d", &conn->recv_timeout);
3259 break;
3260 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3261 sscanf(buf, "%d", &conn->max_recv_dlength);
3262 break;
3263 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3264 sscanf(buf, "%d", &conn->max_xmit_dlength);
3265 break;
3266 case ISCSI_PARAM_HDRDGST_EN:
3267 sscanf(buf, "%d", &conn->hdrdgst_en);
3268 break;
3269 case ISCSI_PARAM_DATADGST_EN:
3270 sscanf(buf, "%d", &conn->datadgst_en);
3271 break;
3272 case ISCSI_PARAM_INITIAL_R2T_EN:
3273 sscanf(buf, "%d", &session->initial_r2t_en);
3274 break;
3275 case ISCSI_PARAM_MAX_R2T:
3276 sscanf(buf, "%hu", &session->max_r2t);
3277 break;
3278 case ISCSI_PARAM_IMM_DATA_EN:
3279 sscanf(buf, "%d", &session->imm_data_en);
3280 break;
3281 case ISCSI_PARAM_FIRST_BURST:
3282 sscanf(buf, "%d", &session->first_burst);
3283 break;
3284 case ISCSI_PARAM_MAX_BURST:
3285 sscanf(buf, "%d", &session->max_burst);
3286 break;
3287 case ISCSI_PARAM_PDU_INORDER_EN:
3288 sscanf(buf, "%d", &session->pdu_inorder_en);
3289 break;
3290 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3291 sscanf(buf, "%d", &session->dataseq_inorder_en);
3292 break;
3293 case ISCSI_PARAM_ERL:
3294 sscanf(buf, "%d", &session->erl);
3295 break;
3296 case ISCSI_PARAM_EXP_STATSN:
3297 sscanf(buf, "%u", &conn->exp_statsn);
3298 break;
3299 case ISCSI_PARAM_USERNAME:
3300 return iscsi_switch_str_param(&session->username, buf);
3301 case ISCSI_PARAM_USERNAME_IN:
3302 return iscsi_switch_str_param(&session->username_in, buf);
3303 case ISCSI_PARAM_PASSWORD:
3304 return iscsi_switch_str_param(&session->password, buf);
3305 case ISCSI_PARAM_PASSWORD_IN:
3306 return iscsi_switch_str_param(&session->password_in, buf);
3307 case ISCSI_PARAM_TARGET_NAME:
3308 return iscsi_switch_str_param(&session->targetname, buf);
3309 case ISCSI_PARAM_TARGET_ALIAS:
3310 return iscsi_switch_str_param(&session->targetalias, buf);
3311 case ISCSI_PARAM_TPGT:
3312 sscanf(buf, "%d", &session->tpgt);
3313 break;
3314 case ISCSI_PARAM_PERSISTENT_PORT:
3315 sscanf(buf, "%d", &conn->persistent_port);
3316 break;
3317 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3318 return iscsi_switch_str_param(&conn->persistent_address, buf);
3319 case ISCSI_PARAM_IFACE_NAME:
3320 return iscsi_switch_str_param(&session->ifacename, buf);
3321 case ISCSI_PARAM_INITIATOR_NAME:
3322 return iscsi_switch_str_param(&session->initiatorname, buf);
3323 case ISCSI_PARAM_BOOT_ROOT:
3324 return iscsi_switch_str_param(&session->boot_root, buf);
3325 case ISCSI_PARAM_BOOT_NIC:
3326 return iscsi_switch_str_param(&session->boot_nic, buf);
3327 case ISCSI_PARAM_BOOT_TARGET:
3328 return iscsi_switch_str_param(&session->boot_target, buf);
3329 case ISCSI_PARAM_PORTAL_TYPE:
3330 return iscsi_switch_str_param(&session->portal_type, buf);
3331 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3332 return iscsi_switch_str_param(&session->discovery_parent_type,
3333 buf);
3334 case ISCSI_PARAM_DISCOVERY_SESS:
3335 sscanf(buf, "%d", &val);
3336 session->discovery_sess = !!val;
3337 break;
3338 case ISCSI_PARAM_LOCAL_IPADDR:
3339 return iscsi_switch_str_param(&conn->local_ipaddr, buf);
3340 default:
3341 return -ENOSYS;
3342 }
3343
3344 return 0;
3345}
3346EXPORT_SYMBOL_GPL(iscsi_set_param);
3347
3348int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
3349 enum iscsi_param param, char *buf)
3350{
3351 struct iscsi_session *session = cls_session->dd_data;
3352 int len;
3353
3354 switch(param) {
3355 case ISCSI_PARAM_FAST_ABORT:
3356 len = sprintf(buf, "%d\n", session->fast_abort);
3357 break;
3358 case ISCSI_PARAM_ABORT_TMO:
3359 len = sprintf(buf, "%d\n", session->abort_timeout);
3360 break;
3361 case ISCSI_PARAM_LU_RESET_TMO:
3362 len = sprintf(buf, "%d\n", session->lu_reset_timeout);
3363 break;
3364 case ISCSI_PARAM_TGT_RESET_TMO:
3365 len = sprintf(buf, "%d\n", session->tgt_reset_timeout);
3366 break;
3367 case ISCSI_PARAM_INITIAL_R2T_EN:
3368 len = sprintf(buf, "%d\n", session->initial_r2t_en);
3369 break;
3370 case ISCSI_PARAM_MAX_R2T:
3371 len = sprintf(buf, "%hu\n", session->max_r2t);
3372 break;
3373 case ISCSI_PARAM_IMM_DATA_EN:
3374 len = sprintf(buf, "%d\n", session->imm_data_en);
3375 break;
3376 case ISCSI_PARAM_FIRST_BURST:
3377 len = sprintf(buf, "%u\n", session->first_burst);
3378 break;
3379 case ISCSI_PARAM_MAX_BURST:
3380 len = sprintf(buf, "%u\n", session->max_burst);
3381 break;
3382 case ISCSI_PARAM_PDU_INORDER_EN:
3383 len = sprintf(buf, "%d\n", session->pdu_inorder_en);
3384 break;
3385 case ISCSI_PARAM_DATASEQ_INORDER_EN:
3386 len = sprintf(buf, "%d\n", session->dataseq_inorder_en);
3387 break;
3388 case ISCSI_PARAM_DEF_TASKMGMT_TMO:
3389 len = sprintf(buf, "%d\n", session->def_taskmgmt_tmo);
3390 break;
3391 case ISCSI_PARAM_ERL:
3392 len = sprintf(buf, "%d\n", session->erl);
3393 break;
3394 case ISCSI_PARAM_TARGET_NAME:
3395 len = sprintf(buf, "%s\n", session->targetname);
3396 break;
3397 case ISCSI_PARAM_TARGET_ALIAS:
3398 len = sprintf(buf, "%s\n", session->targetalias);
3399 break;
3400 case ISCSI_PARAM_TPGT:
3401 len = sprintf(buf, "%d\n", session->tpgt);
3402 break;
3403 case ISCSI_PARAM_USERNAME:
3404 len = sprintf(buf, "%s\n", session->username);
3405 break;
3406 case ISCSI_PARAM_USERNAME_IN:
3407 len = sprintf(buf, "%s\n", session->username_in);
3408 break;
3409 case ISCSI_PARAM_PASSWORD:
3410 len = sprintf(buf, "%s\n", session->password);
3411 break;
3412 case ISCSI_PARAM_PASSWORD_IN:
3413 len = sprintf(buf, "%s\n", session->password_in);
3414 break;
3415 case ISCSI_PARAM_IFACE_NAME:
3416 len = sprintf(buf, "%s\n", session->ifacename);
3417 break;
3418 case ISCSI_PARAM_INITIATOR_NAME:
3419 len = sprintf(buf, "%s\n", session->initiatorname);
3420 break;
3421 case ISCSI_PARAM_BOOT_ROOT:
3422 len = sprintf(buf, "%s\n", session->boot_root);
3423 break;
3424 case ISCSI_PARAM_BOOT_NIC:
3425 len = sprintf(buf, "%s\n", session->boot_nic);
3426 break;
3427 case ISCSI_PARAM_BOOT_TARGET:
3428 len = sprintf(buf, "%s\n", session->boot_target);
3429 break;
3430 case ISCSI_PARAM_AUTO_SND_TGT_DISABLE:
3431 len = sprintf(buf, "%u\n", session->auto_snd_tgt_disable);
3432 break;
3433 case ISCSI_PARAM_DISCOVERY_SESS:
3434 len = sprintf(buf, "%u\n", session->discovery_sess);
3435 break;
3436 case ISCSI_PARAM_PORTAL_TYPE:
3437 len = sprintf(buf, "%s\n", session->portal_type);
3438 break;
3439 case ISCSI_PARAM_CHAP_AUTH_EN:
3440 len = sprintf(buf, "%u\n", session->chap_auth_en);
3441 break;
3442 case ISCSI_PARAM_DISCOVERY_LOGOUT_EN:
3443 len = sprintf(buf, "%u\n", session->discovery_logout_en);
3444 break;
3445 case ISCSI_PARAM_BIDI_CHAP_EN:
3446 len = sprintf(buf, "%u\n", session->bidi_chap_en);
3447 break;
3448 case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL:
3449 len = sprintf(buf, "%u\n", session->discovery_auth_optional);
3450 break;
3451 case ISCSI_PARAM_DEF_TIME2WAIT:
3452 len = sprintf(buf, "%d\n", session->time2wait);
3453 break;
3454 case ISCSI_PARAM_DEF_TIME2RETAIN:
3455 len = sprintf(buf, "%d\n", session->time2retain);
3456 break;
3457 case ISCSI_PARAM_TSID:
3458 len = sprintf(buf, "%u\n", session->tsid);
3459 break;
3460 case ISCSI_PARAM_ISID:
3461 len = sprintf(buf, "%02x%02x%02x%02x%02x%02x\n",
3462 session->isid[0], session->isid[1],
3463 session->isid[2], session->isid[3],
3464 session->isid[4], session->isid[5]);
3465 break;
3466 case ISCSI_PARAM_DISCOVERY_PARENT_IDX:
3467 len = sprintf(buf, "%u\n", session->discovery_parent_idx);
3468 break;
3469 case ISCSI_PARAM_DISCOVERY_PARENT_TYPE:
3470 if (session->discovery_parent_type)
3471 len = sprintf(buf, "%s\n",
3472 session->discovery_parent_type);
3473 else
3474 len = sprintf(buf, "\n");
3475 break;
3476 default:
3477 return -ENOSYS;
3478 }
3479
3480 return len;
3481}
3482EXPORT_SYMBOL_GPL(iscsi_session_get_param);
3483
3484int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
3485 enum iscsi_param param, char *buf)
3486{
3487 struct sockaddr_in6 *sin6 = NULL;
3488 struct sockaddr_in *sin = NULL;
3489 int len;
3490
3491 switch (addr->ss_family) {
3492 case AF_INET:
3493 sin = (struct sockaddr_in *)addr;
3494 break;
3495 case AF_INET6:
3496 sin6 = (struct sockaddr_in6 *)addr;
3497 break;
3498 default:
3499 return -EINVAL;
3500 }
3501
3502 switch (param) {
3503 case ISCSI_PARAM_CONN_ADDRESS:
3504 case ISCSI_HOST_PARAM_IPADDRESS:
3505 if (sin)
3506 len = sprintf(buf, "%pI4\n", &sin->sin_addr.s_addr);
3507 else
3508 len = sprintf(buf, "%pI6\n", &sin6->sin6_addr);
3509 break;
3510 case ISCSI_PARAM_CONN_PORT:
3511 case ISCSI_PARAM_LOCAL_PORT:
3512 if (sin)
3513 len = sprintf(buf, "%hu\n", be16_to_cpu(sin->sin_port));
3514 else
3515 len = sprintf(buf, "%hu\n",
3516 be16_to_cpu(sin6->sin6_port));
3517 break;
3518 default:
3519 return -EINVAL;
3520 }
3521
3522 return len;
3523}
3524EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param);
3525
3526int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
3527 enum iscsi_param param, char *buf)
3528{
3529 struct iscsi_conn *conn = cls_conn->dd_data;
3530 int len;
3531
3532 switch(param) {
3533 case ISCSI_PARAM_PING_TMO:
3534 len = sprintf(buf, "%u\n", conn->ping_timeout);
3535 break;
3536 case ISCSI_PARAM_RECV_TMO:
3537 len = sprintf(buf, "%u\n", conn->recv_timeout);
3538 break;
3539 case ISCSI_PARAM_MAX_RECV_DLENGTH:
3540 len = sprintf(buf, "%u\n", conn->max_recv_dlength);
3541 break;
3542 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
3543 len = sprintf(buf, "%u\n", conn->max_xmit_dlength);
3544 break;
3545 case ISCSI_PARAM_HDRDGST_EN:
3546 len = sprintf(buf, "%d\n", conn->hdrdgst_en);
3547 break;
3548 case ISCSI_PARAM_DATADGST_EN:
3549 len = sprintf(buf, "%d\n", conn->datadgst_en);
3550 break;
3551 case ISCSI_PARAM_IFMARKER_EN:
3552 len = sprintf(buf, "%d\n", conn->ifmarker_en);
3553 break;
3554 case ISCSI_PARAM_OFMARKER_EN:
3555 len = sprintf(buf, "%d\n", conn->ofmarker_en);
3556 break;
3557 case ISCSI_PARAM_EXP_STATSN:
3558 len = sprintf(buf, "%u\n", conn->exp_statsn);
3559 break;
3560 case ISCSI_PARAM_PERSISTENT_PORT:
3561 len = sprintf(buf, "%d\n", conn->persistent_port);
3562 break;
3563 case ISCSI_PARAM_PERSISTENT_ADDRESS:
3564 len = sprintf(buf, "%s\n", conn->persistent_address);
3565 break;
3566 case ISCSI_PARAM_STATSN:
3567 len = sprintf(buf, "%u\n", conn->statsn);
3568 break;
3569 case ISCSI_PARAM_MAX_SEGMENT_SIZE:
3570 len = sprintf(buf, "%u\n", conn->max_segment_size);
3571 break;
3572 case ISCSI_PARAM_KEEPALIVE_TMO:
3573 len = sprintf(buf, "%u\n", conn->keepalive_tmo);
3574 break;
3575 case ISCSI_PARAM_LOCAL_PORT:
3576 len = sprintf(buf, "%u\n", conn->local_port);
3577 break;
3578 case ISCSI_PARAM_TCP_TIMESTAMP_STAT:
3579 len = sprintf(buf, "%u\n", conn->tcp_timestamp_stat);
3580 break;
3581 case ISCSI_PARAM_TCP_NAGLE_DISABLE:
3582 len = sprintf(buf, "%u\n", conn->tcp_nagle_disable);
3583 break;
3584 case ISCSI_PARAM_TCP_WSF_DISABLE:
3585 len = sprintf(buf, "%u\n", conn->tcp_wsf_disable);
3586 break;
3587 case ISCSI_PARAM_TCP_TIMER_SCALE:
3588 len = sprintf(buf, "%u\n", conn->tcp_timer_scale);
3589 break;
3590 case ISCSI_PARAM_TCP_TIMESTAMP_EN:
3591 len = sprintf(buf, "%u\n", conn->tcp_timestamp_en);
3592 break;
3593 case ISCSI_PARAM_IP_FRAGMENT_DISABLE:
3594 len = sprintf(buf, "%u\n", conn->fragment_disable);
3595 break;
3596 case ISCSI_PARAM_IPV4_TOS:
3597 len = sprintf(buf, "%u\n", conn->ipv4_tos);
3598 break;
3599 case ISCSI_PARAM_IPV6_TC:
3600 len = sprintf(buf, "%u\n", conn->ipv6_traffic_class);
3601 break;
3602 case ISCSI_PARAM_IPV6_FLOW_LABEL:
3603 len = sprintf(buf, "%u\n", conn->ipv6_flow_label);
3604 break;
3605 case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6:
3606 len = sprintf(buf, "%u\n", conn->is_fw_assigned_ipv6);
3607 break;
3608 case ISCSI_PARAM_TCP_XMIT_WSF:
3609 len = sprintf(buf, "%u\n", conn->tcp_xmit_wsf);
3610 break;
3611 case ISCSI_PARAM_TCP_RECV_WSF:
3612 len = sprintf(buf, "%u\n", conn->tcp_recv_wsf);
3613 break;
3614 case ISCSI_PARAM_LOCAL_IPADDR:
3615 len = sprintf(buf, "%s\n", conn->local_ipaddr);
3616 break;
3617 default:
3618 return -ENOSYS;
3619 }
3620
3621 return len;
3622}
3623EXPORT_SYMBOL_GPL(iscsi_conn_get_param);
3624
3625int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3626 char *buf)
3627{
3628 struct iscsi_host *ihost = shost_priv(shost);
3629 int len;
3630
3631 switch (param) {
3632 case ISCSI_HOST_PARAM_NETDEV_NAME:
3633 len = sprintf(buf, "%s\n", ihost->netdev);
3634 break;
3635 case ISCSI_HOST_PARAM_HWADDRESS:
3636 len = sprintf(buf, "%s\n", ihost->hwaddress);
3637 break;
3638 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3639 len = sprintf(buf, "%s\n", ihost->initiatorname);
3640 break;
3641 default:
3642 return -ENOSYS;
3643 }
3644
3645 return len;
3646}
3647EXPORT_SYMBOL_GPL(iscsi_host_get_param);
3648
3649int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param,
3650 char *buf, int buflen)
3651{
3652 struct iscsi_host *ihost = shost_priv(shost);
3653
3654 switch (param) {
3655 case ISCSI_HOST_PARAM_NETDEV_NAME:
3656 return iscsi_switch_str_param(&ihost->netdev, buf);
3657 case ISCSI_HOST_PARAM_HWADDRESS:
3658 return iscsi_switch_str_param(&ihost->hwaddress, buf);
3659 case ISCSI_HOST_PARAM_INITIATOR_NAME:
3660 return iscsi_switch_str_param(&ihost->initiatorname, buf);
3661 default:
3662 return -ENOSYS;
3663 }
3664
3665 return 0;
3666}
3667EXPORT_SYMBOL_GPL(iscsi_host_set_param);
3668
3669MODULE_AUTHOR("Mike Christie");
3670MODULE_DESCRIPTION("iSCSI library functions");
3671MODULE_LICENSE("GPL");