xref: /linux/drivers/target/iscsi/iscsi_target_util.c (revision 0d3b051adbb72ed81956447d0d1e54d5943ee6f5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * This file contains the iSCSI Target specific utility functions.
4  *
5  * (c) Copyright 2007-2013 Datera, Inc.
6  *
7  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
8  *
9  ******************************************************************************/
10 
11 #include <linux/list.h>
12 #include <linux/sched/signal.h>
13 #include <net/ipv6.h>         /* ipv6_addr_equal() */
14 #include <scsi/scsi_tcq.h>
15 #include <scsi/iscsi_proto.h>
16 #include <target/target_core_base.h>
17 #include <target/target_core_fabric.h>
18 #include <target/iscsi/iscsi_transport.h>
19 
20 #include <target/iscsi/iscsi_target_core.h>
21 #include "iscsi_target_parameters.h"
22 #include "iscsi_target_seq_pdu_list.h"
23 #include "iscsi_target_datain_values.h"
24 #include "iscsi_target_erl0.h"
25 #include "iscsi_target_erl1.h"
26 #include "iscsi_target_erl2.h"
27 #include "iscsi_target_tpg.h"
28 #include "iscsi_target_util.h"
29 #include "iscsi_target.h"
30 
31 #define PRINT_BUFF(buff, len)					\
32 {								\
33 	int zzz;						\
34 								\
35 	pr_debug("%d:\n", __LINE__);				\
36 	for (zzz = 0; zzz < len; zzz++) {			\
37 		if (zzz % 16 == 0) {				\
38 			if (zzz)				\
39 				pr_debug("\n");			\
40 			pr_debug("%4i: ", zzz);			\
41 		}						\
42 		pr_debug("%02x ", (unsigned char) (buff)[zzz]);	\
43 	}							\
44 	if ((len + 1) % 16)					\
45 		pr_debug("\n");					\
46 }
47 
48 extern struct list_head g_tiqn_list;
49 extern spinlock_t tiqn_lock;
50 
51 int iscsit_add_r2t_to_list(
52 	struct iscsi_cmd *cmd,
53 	u32 offset,
54 	u32 xfer_len,
55 	int recovery,
56 	u32 r2t_sn)
57 {
58 	struct iscsi_r2t *r2t;
59 
60 	lockdep_assert_held(&cmd->r2t_lock);
61 
62 	WARN_ON_ONCE((s32)xfer_len < 0);
63 
64 	r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
65 	if (!r2t) {
66 		pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
67 		return -1;
68 	}
69 	INIT_LIST_HEAD(&r2t->r2t_list);
70 
71 	r2t->recovery_r2t = recovery;
72 	r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
73 	r2t->offset = offset;
74 	r2t->xfer_len = xfer_len;
75 	list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
76 	spin_unlock_bh(&cmd->r2t_lock);
77 
78 	iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
79 
80 	spin_lock_bh(&cmd->r2t_lock);
81 	return 0;
82 }
83 
84 struct iscsi_r2t *iscsit_get_r2t_for_eos(
85 	struct iscsi_cmd *cmd,
86 	u32 offset,
87 	u32 length)
88 {
89 	struct iscsi_r2t *r2t;
90 
91 	spin_lock_bh(&cmd->r2t_lock);
92 	list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
93 		if ((r2t->offset <= offset) &&
94 		    (r2t->offset + r2t->xfer_len) >= (offset + length)) {
95 			spin_unlock_bh(&cmd->r2t_lock);
96 			return r2t;
97 		}
98 	}
99 	spin_unlock_bh(&cmd->r2t_lock);
100 
101 	pr_err("Unable to locate R2T for Offset: %u, Length:"
102 			" %u\n", offset, length);
103 	return NULL;
104 }
105 
106 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
107 {
108 	struct iscsi_r2t *r2t;
109 
110 	spin_lock_bh(&cmd->r2t_lock);
111 	list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
112 		if (!r2t->sent_r2t) {
113 			spin_unlock_bh(&cmd->r2t_lock);
114 			return r2t;
115 		}
116 	}
117 	spin_unlock_bh(&cmd->r2t_lock);
118 
119 	pr_err("Unable to locate next R2T to send for ITT:"
120 			" 0x%08x.\n", cmd->init_task_tag);
121 	return NULL;
122 }
123 
124 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
125 {
126 	lockdep_assert_held(&cmd->r2t_lock);
127 
128 	list_del(&r2t->r2t_list);
129 	kmem_cache_free(lio_r2t_cache, r2t);
130 }
131 
132 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
133 {
134 	struct iscsi_r2t *r2t, *r2t_tmp;
135 
136 	spin_lock_bh(&cmd->r2t_lock);
137 	list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
138 		iscsit_free_r2t(r2t, cmd);
139 	spin_unlock_bh(&cmd->r2t_lock);
140 }
141 
142 static int iscsit_wait_for_tag(struct se_session *se_sess, int state, int *cpup)
143 {
144 	int tag = -1;
145 	DEFINE_SBQ_WAIT(wait);
146 	struct sbq_wait_state *ws;
147 	struct sbitmap_queue *sbq;
148 
149 	if (state == TASK_RUNNING)
150 		return tag;
151 
152 	sbq = &se_sess->sess_tag_pool;
153 	ws = &sbq->ws[0];
154 	for (;;) {
155 		sbitmap_prepare_to_wait(sbq, ws, &wait, state);
156 		if (signal_pending_state(state, current))
157 			break;
158 		tag = sbitmap_queue_get(sbq, cpup);
159 		if (tag >= 0)
160 			break;
161 		schedule();
162 	}
163 
164 	sbitmap_finish_wait(sbq, ws, &wait);
165 	return tag;
166 }
167 
168 /*
169  * May be called from software interrupt (timer) context for allocating
170  * iSCSI NopINs.
171  */
172 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, int state)
173 {
174 	struct iscsi_cmd *cmd;
175 	struct se_session *se_sess = conn->sess->se_sess;
176 	int size, tag, cpu;
177 
178 	tag = sbitmap_queue_get(&se_sess->sess_tag_pool, &cpu);
179 	if (tag < 0)
180 		tag = iscsit_wait_for_tag(se_sess, state, &cpu);
181 	if (tag < 0)
182 		return NULL;
183 
184 	size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
185 	cmd = (struct iscsi_cmd *)(se_sess->sess_cmd_map + (tag * size));
186 	memset(cmd, 0, size);
187 
188 	cmd->se_cmd.map_tag = tag;
189 	cmd->se_cmd.map_cpu = cpu;
190 	cmd->conn = conn;
191 	cmd->data_direction = DMA_NONE;
192 	INIT_LIST_HEAD(&cmd->i_conn_node);
193 	INIT_LIST_HEAD(&cmd->datain_list);
194 	INIT_LIST_HEAD(&cmd->cmd_r2t_list);
195 	spin_lock_init(&cmd->datain_lock);
196 	spin_lock_init(&cmd->dataout_timeout_lock);
197 	spin_lock_init(&cmd->istate_lock);
198 	spin_lock_init(&cmd->error_lock);
199 	spin_lock_init(&cmd->r2t_lock);
200 	timer_setup(&cmd->dataout_timer, iscsit_handle_dataout_timeout, 0);
201 
202 	return cmd;
203 }
204 EXPORT_SYMBOL(iscsit_allocate_cmd);
205 
206 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
207 	struct iscsi_cmd *cmd,
208 	u32 seq_send_order)
209 {
210 	u32 i;
211 
212 	for (i = 0; i < cmd->seq_count; i++)
213 		if (cmd->seq_list[i].seq_send_order == seq_send_order)
214 			return &cmd->seq_list[i];
215 
216 	return NULL;
217 }
218 
219 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
220 {
221 	u32 i;
222 
223 	if (!cmd->seq_list) {
224 		pr_err("struct iscsi_cmd->seq_list is NULL!\n");
225 		return NULL;
226 	}
227 
228 	for (i = 0; i < cmd->seq_count; i++) {
229 		if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
230 			continue;
231 		if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
232 			cmd->seq_send_order++;
233 			return &cmd->seq_list[i];
234 		}
235 	}
236 
237 	return NULL;
238 }
239 
240 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
241 	struct iscsi_cmd *cmd,
242 	u32 r2t_sn)
243 {
244 	struct iscsi_r2t *r2t;
245 
246 	spin_lock_bh(&cmd->r2t_lock);
247 	list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
248 		if (r2t->r2t_sn == r2t_sn) {
249 			spin_unlock_bh(&cmd->r2t_lock);
250 			return r2t;
251 		}
252 	}
253 	spin_unlock_bh(&cmd->r2t_lock);
254 
255 	return NULL;
256 }
257 
258 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
259 {
260 	u32 max_cmdsn;
261 	int ret;
262 
263 	/*
264 	 * This is the proper method of checking received CmdSN against
265 	 * ExpCmdSN and MaxCmdSN values, as well as accounting for out
266 	 * or order CmdSNs due to multiple connection sessions and/or
267 	 * CRC failures.
268 	 */
269 	max_cmdsn = atomic_read(&sess->max_cmd_sn);
270 	if (iscsi_sna_gt(cmdsn, max_cmdsn)) {
271 		pr_err("Received CmdSN: 0x%08x is greater than"
272 		       " MaxCmdSN: 0x%08x, ignoring.\n", cmdsn, max_cmdsn);
273 		ret = CMDSN_MAXCMDSN_OVERRUN;
274 
275 	} else if (cmdsn == sess->exp_cmd_sn) {
276 		sess->exp_cmd_sn++;
277 		pr_debug("Received CmdSN matches ExpCmdSN,"
278 		      " incremented ExpCmdSN to: 0x%08x\n",
279 		      sess->exp_cmd_sn);
280 		ret = CMDSN_NORMAL_OPERATION;
281 
282 	} else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
283 		pr_debug("Received CmdSN: 0x%08x is greater"
284 		      " than ExpCmdSN: 0x%08x, not acknowledging.\n",
285 		      cmdsn, sess->exp_cmd_sn);
286 		ret = CMDSN_HIGHER_THAN_EXP;
287 
288 	} else {
289 		pr_err("Received CmdSN: 0x%08x is less than"
290 		       " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
291 		       sess->exp_cmd_sn);
292 		ret = CMDSN_LOWER_THAN_EXP;
293 	}
294 
295 	return ret;
296 }
297 
298 /*
299  * Commands may be received out of order if MC/S is in use.
300  * Ensure they are executed in CmdSN order.
301  */
302 int iscsit_sequence_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
303 			unsigned char *buf, __be32 cmdsn)
304 {
305 	int ret, cmdsn_ret;
306 	bool reject = false;
307 	u8 reason = ISCSI_REASON_BOOKMARK_NO_RESOURCES;
308 
309 	mutex_lock(&conn->sess->cmdsn_mutex);
310 
311 	cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, be32_to_cpu(cmdsn));
312 	switch (cmdsn_ret) {
313 	case CMDSN_NORMAL_OPERATION:
314 		ret = iscsit_execute_cmd(cmd, 0);
315 		if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
316 			iscsit_execute_ooo_cmdsns(conn->sess);
317 		else if (ret < 0) {
318 			reject = true;
319 			ret = CMDSN_ERROR_CANNOT_RECOVER;
320 		}
321 		break;
322 	case CMDSN_HIGHER_THAN_EXP:
323 		ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, be32_to_cpu(cmdsn));
324 		if (ret < 0) {
325 			reject = true;
326 			ret = CMDSN_ERROR_CANNOT_RECOVER;
327 			break;
328 		}
329 		ret = CMDSN_HIGHER_THAN_EXP;
330 		break;
331 	case CMDSN_LOWER_THAN_EXP:
332 	case CMDSN_MAXCMDSN_OVERRUN:
333 	default:
334 		cmd->i_state = ISTATE_REMOVE;
335 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
336 		/*
337 		 * Existing callers for iscsit_sequence_cmd() will silently
338 		 * ignore commands with CMDSN_LOWER_THAN_EXP, so force this
339 		 * return for CMDSN_MAXCMDSN_OVERRUN as well..
340 		 */
341 		ret = CMDSN_LOWER_THAN_EXP;
342 		break;
343 	}
344 	mutex_unlock(&conn->sess->cmdsn_mutex);
345 
346 	if (reject)
347 		iscsit_reject_cmd(cmd, reason, buf);
348 
349 	return ret;
350 }
351 EXPORT_SYMBOL(iscsit_sequence_cmd);
352 
353 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
354 {
355 	struct iscsi_conn *conn = cmd->conn;
356 	struct se_cmd *se_cmd = &cmd->se_cmd;
357 	struct iscsi_data *hdr = (struct iscsi_data *) buf;
358 	u32 payload_length = ntoh24(hdr->dlength);
359 
360 	if (conn->sess->sess_ops->InitialR2T) {
361 		pr_err("Received unexpected unsolicited data"
362 			" while InitialR2T=Yes, protocol error.\n");
363 		transport_send_check_condition_and_sense(se_cmd,
364 				TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
365 		return -1;
366 	}
367 
368 	if ((cmd->first_burst_len + payload_length) >
369 	     conn->sess->sess_ops->FirstBurstLength) {
370 		pr_err("Total %u bytes exceeds FirstBurstLength: %u"
371 			" for this Unsolicited DataOut Burst.\n",
372 			(cmd->first_burst_len + payload_length),
373 				conn->sess->sess_ops->FirstBurstLength);
374 		transport_send_check_condition_and_sense(se_cmd,
375 				TCM_INCORRECT_AMOUNT_OF_DATA, 0);
376 		return -1;
377 	}
378 
379 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
380 		return 0;
381 
382 	if (((cmd->first_burst_len + payload_length) != cmd->se_cmd.data_length) &&
383 	    ((cmd->first_burst_len + payload_length) !=
384 	      conn->sess->sess_ops->FirstBurstLength)) {
385 		pr_err("Unsolicited non-immediate data received %u"
386 			" does not equal FirstBurstLength: %u, and does"
387 			" not equal ExpXferLen %u.\n",
388 			(cmd->first_burst_len + payload_length),
389 			conn->sess->sess_ops->FirstBurstLength, cmd->se_cmd.data_length);
390 		transport_send_check_condition_and_sense(se_cmd,
391 				TCM_INCORRECT_AMOUNT_OF_DATA, 0);
392 		return -1;
393 	}
394 	return 0;
395 }
396 
397 struct iscsi_cmd *iscsit_find_cmd_from_itt(
398 	struct iscsi_conn *conn,
399 	itt_t init_task_tag)
400 {
401 	struct iscsi_cmd *cmd;
402 
403 	spin_lock_bh(&conn->cmd_lock);
404 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
405 		if (cmd->init_task_tag == init_task_tag) {
406 			spin_unlock_bh(&conn->cmd_lock);
407 			return cmd;
408 		}
409 	}
410 	spin_unlock_bh(&conn->cmd_lock);
411 
412 	pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
413 			init_task_tag, conn->cid);
414 	return NULL;
415 }
416 EXPORT_SYMBOL(iscsit_find_cmd_from_itt);
417 
418 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
419 	struct iscsi_conn *conn,
420 	itt_t init_task_tag,
421 	u32 length)
422 {
423 	struct iscsi_cmd *cmd;
424 
425 	spin_lock_bh(&conn->cmd_lock);
426 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
427 		if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT)
428 			continue;
429 		if (cmd->init_task_tag == init_task_tag) {
430 			spin_unlock_bh(&conn->cmd_lock);
431 			return cmd;
432 		}
433 	}
434 	spin_unlock_bh(&conn->cmd_lock);
435 
436 	pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
437 			" dumping payload\n", init_task_tag, conn->cid);
438 	if (length)
439 		iscsit_dump_data_payload(conn, length, 1);
440 
441 	return NULL;
442 }
443 EXPORT_SYMBOL(iscsit_find_cmd_from_itt_or_dump);
444 
445 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
446 	struct iscsi_conn *conn,
447 	u32 targ_xfer_tag)
448 {
449 	struct iscsi_cmd *cmd = NULL;
450 
451 	spin_lock_bh(&conn->cmd_lock);
452 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
453 		if (cmd->targ_xfer_tag == targ_xfer_tag) {
454 			spin_unlock_bh(&conn->cmd_lock);
455 			return cmd;
456 		}
457 	}
458 	spin_unlock_bh(&conn->cmd_lock);
459 
460 	pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
461 			targ_xfer_tag, conn->cid);
462 	return NULL;
463 }
464 
465 int iscsit_find_cmd_for_recovery(
466 	struct iscsi_session *sess,
467 	struct iscsi_cmd **cmd_ptr,
468 	struct iscsi_conn_recovery **cr_ptr,
469 	itt_t init_task_tag)
470 {
471 	struct iscsi_cmd *cmd = NULL;
472 	struct iscsi_conn_recovery *cr;
473 	/*
474 	 * Scan through the inactive connection recovery list's command list.
475 	 * If init_task_tag matches the command is still alligent.
476 	 */
477 	spin_lock(&sess->cr_i_lock);
478 	list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
479 		spin_lock(&cr->conn_recovery_cmd_lock);
480 		list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
481 			if (cmd->init_task_tag == init_task_tag) {
482 				spin_unlock(&cr->conn_recovery_cmd_lock);
483 				spin_unlock(&sess->cr_i_lock);
484 
485 				*cr_ptr = cr;
486 				*cmd_ptr = cmd;
487 				return -2;
488 			}
489 		}
490 		spin_unlock(&cr->conn_recovery_cmd_lock);
491 	}
492 	spin_unlock(&sess->cr_i_lock);
493 	/*
494 	 * Scan through the active connection recovery list's command list.
495 	 * If init_task_tag matches the command is ready to be reassigned.
496 	 */
497 	spin_lock(&sess->cr_a_lock);
498 	list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
499 		spin_lock(&cr->conn_recovery_cmd_lock);
500 		list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_conn_node) {
501 			if (cmd->init_task_tag == init_task_tag) {
502 				spin_unlock(&cr->conn_recovery_cmd_lock);
503 				spin_unlock(&sess->cr_a_lock);
504 
505 				*cr_ptr = cr;
506 				*cmd_ptr = cmd;
507 				return 0;
508 			}
509 		}
510 		spin_unlock(&cr->conn_recovery_cmd_lock);
511 	}
512 	spin_unlock(&sess->cr_a_lock);
513 
514 	return -1;
515 }
516 
517 void iscsit_add_cmd_to_immediate_queue(
518 	struct iscsi_cmd *cmd,
519 	struct iscsi_conn *conn,
520 	u8 state)
521 {
522 	struct iscsi_queue_req *qr;
523 
524 	qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
525 	if (!qr) {
526 		pr_err("Unable to allocate memory for"
527 				" struct iscsi_queue_req\n");
528 		return;
529 	}
530 	INIT_LIST_HEAD(&qr->qr_list);
531 	qr->cmd = cmd;
532 	qr->state = state;
533 
534 	spin_lock_bh(&conn->immed_queue_lock);
535 	list_add_tail(&qr->qr_list, &conn->immed_queue_list);
536 	atomic_inc(&cmd->immed_queue_count);
537 	atomic_set(&conn->check_immediate_queue, 1);
538 	spin_unlock_bh(&conn->immed_queue_lock);
539 
540 	wake_up(&conn->queues_wq);
541 }
542 EXPORT_SYMBOL(iscsit_add_cmd_to_immediate_queue);
543 
544 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
545 {
546 	struct iscsi_queue_req *qr;
547 
548 	spin_lock_bh(&conn->immed_queue_lock);
549 	if (list_empty(&conn->immed_queue_list)) {
550 		spin_unlock_bh(&conn->immed_queue_lock);
551 		return NULL;
552 	}
553 	qr = list_first_entry(&conn->immed_queue_list,
554 			      struct iscsi_queue_req, qr_list);
555 
556 	list_del(&qr->qr_list);
557 	if (qr->cmd)
558 		atomic_dec(&qr->cmd->immed_queue_count);
559 	spin_unlock_bh(&conn->immed_queue_lock);
560 
561 	return qr;
562 }
563 
564 static void iscsit_remove_cmd_from_immediate_queue(
565 	struct iscsi_cmd *cmd,
566 	struct iscsi_conn *conn)
567 {
568 	struct iscsi_queue_req *qr, *qr_tmp;
569 
570 	spin_lock_bh(&conn->immed_queue_lock);
571 	if (!atomic_read(&cmd->immed_queue_count)) {
572 		spin_unlock_bh(&conn->immed_queue_lock);
573 		return;
574 	}
575 
576 	list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
577 		if (qr->cmd != cmd)
578 			continue;
579 
580 		atomic_dec(&qr->cmd->immed_queue_count);
581 		list_del(&qr->qr_list);
582 		kmem_cache_free(lio_qr_cache, qr);
583 	}
584 	spin_unlock_bh(&conn->immed_queue_lock);
585 
586 	if (atomic_read(&cmd->immed_queue_count)) {
587 		pr_err("ITT: 0x%08x immed_queue_count: %d\n",
588 			cmd->init_task_tag,
589 			atomic_read(&cmd->immed_queue_count));
590 	}
591 }
592 
593 int iscsit_add_cmd_to_response_queue(
594 	struct iscsi_cmd *cmd,
595 	struct iscsi_conn *conn,
596 	u8 state)
597 {
598 	struct iscsi_queue_req *qr;
599 
600 	qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
601 	if (!qr) {
602 		pr_err("Unable to allocate memory for"
603 			" struct iscsi_queue_req\n");
604 		return -ENOMEM;
605 	}
606 	INIT_LIST_HEAD(&qr->qr_list);
607 	qr->cmd = cmd;
608 	qr->state = state;
609 
610 	spin_lock_bh(&conn->response_queue_lock);
611 	list_add_tail(&qr->qr_list, &conn->response_queue_list);
612 	atomic_inc(&cmd->response_queue_count);
613 	spin_unlock_bh(&conn->response_queue_lock);
614 
615 	wake_up(&conn->queues_wq);
616 	return 0;
617 }
618 
619 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
620 {
621 	struct iscsi_queue_req *qr;
622 
623 	spin_lock_bh(&conn->response_queue_lock);
624 	if (list_empty(&conn->response_queue_list)) {
625 		spin_unlock_bh(&conn->response_queue_lock);
626 		return NULL;
627 	}
628 
629 	qr = list_first_entry(&conn->response_queue_list,
630 			      struct iscsi_queue_req, qr_list);
631 
632 	list_del(&qr->qr_list);
633 	if (qr->cmd)
634 		atomic_dec(&qr->cmd->response_queue_count);
635 	spin_unlock_bh(&conn->response_queue_lock);
636 
637 	return qr;
638 }
639 
640 static void iscsit_remove_cmd_from_response_queue(
641 	struct iscsi_cmd *cmd,
642 	struct iscsi_conn *conn)
643 {
644 	struct iscsi_queue_req *qr, *qr_tmp;
645 
646 	spin_lock_bh(&conn->response_queue_lock);
647 	if (!atomic_read(&cmd->response_queue_count)) {
648 		spin_unlock_bh(&conn->response_queue_lock);
649 		return;
650 	}
651 
652 	list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
653 				qr_list) {
654 		if (qr->cmd != cmd)
655 			continue;
656 
657 		atomic_dec(&qr->cmd->response_queue_count);
658 		list_del(&qr->qr_list);
659 		kmem_cache_free(lio_qr_cache, qr);
660 	}
661 	spin_unlock_bh(&conn->response_queue_lock);
662 
663 	if (atomic_read(&cmd->response_queue_count)) {
664 		pr_err("ITT: 0x%08x response_queue_count: %d\n",
665 			cmd->init_task_tag,
666 			atomic_read(&cmd->response_queue_count));
667 	}
668 }
669 
670 bool iscsit_conn_all_queues_empty(struct iscsi_conn *conn)
671 {
672 	bool empty;
673 
674 	spin_lock_bh(&conn->immed_queue_lock);
675 	empty = list_empty(&conn->immed_queue_list);
676 	spin_unlock_bh(&conn->immed_queue_lock);
677 
678 	if (!empty)
679 		return empty;
680 
681 	spin_lock_bh(&conn->response_queue_lock);
682 	empty = list_empty(&conn->response_queue_list);
683 	spin_unlock_bh(&conn->response_queue_lock);
684 
685 	return empty;
686 }
687 
688 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
689 {
690 	struct iscsi_queue_req *qr, *qr_tmp;
691 
692 	spin_lock_bh(&conn->immed_queue_lock);
693 	list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
694 		list_del(&qr->qr_list);
695 		if (qr->cmd)
696 			atomic_dec(&qr->cmd->immed_queue_count);
697 
698 		kmem_cache_free(lio_qr_cache, qr);
699 	}
700 	spin_unlock_bh(&conn->immed_queue_lock);
701 
702 	spin_lock_bh(&conn->response_queue_lock);
703 	list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
704 			qr_list) {
705 		list_del(&qr->qr_list);
706 		if (qr->cmd)
707 			atomic_dec(&qr->cmd->response_queue_count);
708 
709 		kmem_cache_free(lio_qr_cache, qr);
710 	}
711 	spin_unlock_bh(&conn->response_queue_lock);
712 }
713 
714 void iscsit_release_cmd(struct iscsi_cmd *cmd)
715 {
716 	struct iscsi_session *sess;
717 	struct se_cmd *se_cmd = &cmd->se_cmd;
718 
719 	WARN_ON(!list_empty(&cmd->i_conn_node));
720 
721 	if (cmd->conn)
722 		sess = cmd->conn->sess;
723 	else
724 		sess = cmd->sess;
725 
726 	BUG_ON(!sess || !sess->se_sess);
727 
728 	kfree(cmd->buf_ptr);
729 	kfree(cmd->pdu_list);
730 	kfree(cmd->seq_list);
731 	kfree(cmd->tmr_req);
732 	kfree(cmd->overflow_buf);
733 	kfree(cmd->iov_data);
734 	kfree(cmd->text_in_ptr);
735 
736 	target_free_tag(sess->se_sess, se_cmd);
737 }
738 EXPORT_SYMBOL(iscsit_release_cmd);
739 
740 void __iscsit_free_cmd(struct iscsi_cmd *cmd, bool check_queues)
741 {
742 	struct iscsi_conn *conn = cmd->conn;
743 
744 	WARN_ON(!list_empty(&cmd->i_conn_node));
745 
746 	if (cmd->data_direction == DMA_TO_DEVICE) {
747 		iscsit_stop_dataout_timer(cmd);
748 		iscsit_free_r2ts_from_list(cmd);
749 	}
750 	if (cmd->data_direction == DMA_FROM_DEVICE)
751 		iscsit_free_all_datain_reqs(cmd);
752 
753 	if (conn && check_queues) {
754 		iscsit_remove_cmd_from_immediate_queue(cmd, conn);
755 		iscsit_remove_cmd_from_response_queue(cmd, conn);
756 	}
757 
758 	if (conn && conn->conn_transport->iscsit_unmap_cmd)
759 		conn->conn_transport->iscsit_unmap_cmd(conn, cmd);
760 }
761 
762 void iscsit_free_cmd(struct iscsi_cmd *cmd, bool shutdown)
763 {
764 	struct se_cmd *se_cmd = cmd->se_cmd.se_tfo ? &cmd->se_cmd : NULL;
765 	int rc;
766 
767 	WARN_ON(!list_empty(&cmd->i_conn_node));
768 
769 	__iscsit_free_cmd(cmd, shutdown);
770 	if (se_cmd) {
771 		rc = transport_generic_free_cmd(se_cmd, shutdown);
772 		if (!rc && shutdown && se_cmd->se_sess) {
773 			__iscsit_free_cmd(cmd, shutdown);
774 			target_put_sess_cmd(se_cmd);
775 		}
776 	} else {
777 		iscsit_release_cmd(cmd);
778 	}
779 }
780 EXPORT_SYMBOL(iscsit_free_cmd);
781 
782 int iscsit_check_session_usage_count(struct iscsi_session *sess)
783 {
784 	spin_lock_bh(&sess->session_usage_lock);
785 	if (sess->session_usage_count != 0) {
786 		sess->session_waiting_on_uc = 1;
787 		spin_unlock_bh(&sess->session_usage_lock);
788 		if (in_interrupt())
789 			return 2;
790 
791 		wait_for_completion(&sess->session_waiting_on_uc_comp);
792 		return 1;
793 	}
794 	spin_unlock_bh(&sess->session_usage_lock);
795 
796 	return 0;
797 }
798 
799 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
800 {
801 	spin_lock_bh(&sess->session_usage_lock);
802 	sess->session_usage_count--;
803 
804 	if (!sess->session_usage_count && sess->session_waiting_on_uc)
805 		complete(&sess->session_waiting_on_uc_comp);
806 
807 	spin_unlock_bh(&sess->session_usage_lock);
808 }
809 
810 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
811 {
812 	spin_lock_bh(&sess->session_usage_lock);
813 	sess->session_usage_count++;
814 	spin_unlock_bh(&sess->session_usage_lock);
815 }
816 
817 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
818 {
819 	struct iscsi_conn *conn;
820 
821 	spin_lock_bh(&sess->conn_lock);
822 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
823 		if ((conn->cid == cid) &&
824 		    (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
825 			iscsit_inc_conn_usage_count(conn);
826 			spin_unlock_bh(&sess->conn_lock);
827 			return conn;
828 		}
829 	}
830 	spin_unlock_bh(&sess->conn_lock);
831 
832 	return NULL;
833 }
834 
835 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
836 {
837 	struct iscsi_conn *conn;
838 
839 	spin_lock_bh(&sess->conn_lock);
840 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
841 		if (conn->cid == cid) {
842 			iscsit_inc_conn_usage_count(conn);
843 			spin_lock(&conn->state_lock);
844 			atomic_set(&conn->connection_wait_rcfr, 1);
845 			spin_unlock(&conn->state_lock);
846 			spin_unlock_bh(&sess->conn_lock);
847 			return conn;
848 		}
849 	}
850 	spin_unlock_bh(&sess->conn_lock);
851 
852 	return NULL;
853 }
854 
855 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
856 {
857 	spin_lock_bh(&conn->conn_usage_lock);
858 	if (conn->conn_usage_count != 0) {
859 		conn->conn_waiting_on_uc = 1;
860 		spin_unlock_bh(&conn->conn_usage_lock);
861 
862 		wait_for_completion(&conn->conn_waiting_on_uc_comp);
863 		return;
864 	}
865 	spin_unlock_bh(&conn->conn_usage_lock);
866 }
867 
868 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
869 {
870 	spin_lock_bh(&conn->conn_usage_lock);
871 	conn->conn_usage_count--;
872 
873 	if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
874 		complete(&conn->conn_waiting_on_uc_comp);
875 
876 	spin_unlock_bh(&conn->conn_usage_lock);
877 }
878 
879 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
880 {
881 	spin_lock_bh(&conn->conn_usage_lock);
882 	conn->conn_usage_count++;
883 	spin_unlock_bh(&conn->conn_usage_lock);
884 }
885 
886 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
887 {
888 	u8 state;
889 	struct iscsi_cmd *cmd;
890 
891 	cmd = iscsit_allocate_cmd(conn, TASK_RUNNING);
892 	if (!cmd)
893 		return -1;
894 
895 	cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
896 	state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
897 				ISTATE_SEND_NOPIN_NO_RESPONSE;
898 	cmd->init_task_tag = RESERVED_ITT;
899 	cmd->targ_xfer_tag = (want_response) ?
900 			     session_get_next_ttt(conn->sess) : 0xFFFFFFFF;
901 	spin_lock_bh(&conn->cmd_lock);
902 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
903 	spin_unlock_bh(&conn->cmd_lock);
904 
905 	if (want_response)
906 		iscsit_start_nopin_response_timer(conn);
907 	iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
908 
909 	return 0;
910 }
911 
912 void iscsit_handle_nopin_response_timeout(struct timer_list *t)
913 {
914 	struct iscsi_conn *conn = from_timer(conn, t, nopin_response_timer);
915 	struct iscsi_session *sess = conn->sess;
916 
917 	iscsit_inc_conn_usage_count(conn);
918 
919 	spin_lock_bh(&conn->nopin_timer_lock);
920 	if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
921 		spin_unlock_bh(&conn->nopin_timer_lock);
922 		iscsit_dec_conn_usage_count(conn);
923 		return;
924 	}
925 
926 	pr_err("Did not receive response to NOPIN on CID: %hu, failing"
927 		" connection for I_T Nexus %s,i,0x%6phN,%s,t,0x%02x\n",
928 		conn->cid, sess->sess_ops->InitiatorName, sess->isid,
929 		sess->tpg->tpg_tiqn->tiqn, (u32)sess->tpg->tpgt);
930 	conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
931 	spin_unlock_bh(&conn->nopin_timer_lock);
932 
933 	iscsit_fill_cxn_timeout_err_stats(sess);
934 	iscsit_cause_connection_reinstatement(conn, 0);
935 	iscsit_dec_conn_usage_count(conn);
936 }
937 
938 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
939 {
940 	struct iscsi_session *sess = conn->sess;
941 	struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
942 
943 	spin_lock_bh(&conn->nopin_timer_lock);
944 	if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
945 		spin_unlock_bh(&conn->nopin_timer_lock);
946 		return;
947 	}
948 
949 	mod_timer(&conn->nopin_response_timer,
950 		(get_jiffies_64() + na->nopin_response_timeout * HZ));
951 	spin_unlock_bh(&conn->nopin_timer_lock);
952 }
953 
954 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
955 {
956 	struct iscsi_session *sess = conn->sess;
957 	struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
958 
959 	spin_lock_bh(&conn->nopin_timer_lock);
960 	if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
961 		spin_unlock_bh(&conn->nopin_timer_lock);
962 		return;
963 	}
964 
965 	conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
966 	conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
967 	mod_timer(&conn->nopin_response_timer,
968 		  jiffies + na->nopin_response_timeout * HZ);
969 
970 	pr_debug("Started NOPIN Response Timer on CID: %d to %u"
971 		" seconds\n", conn->cid, na->nopin_response_timeout);
972 	spin_unlock_bh(&conn->nopin_timer_lock);
973 }
974 
975 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
976 {
977 	spin_lock_bh(&conn->nopin_timer_lock);
978 	if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
979 		spin_unlock_bh(&conn->nopin_timer_lock);
980 		return;
981 	}
982 	conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
983 	spin_unlock_bh(&conn->nopin_timer_lock);
984 
985 	del_timer_sync(&conn->nopin_response_timer);
986 
987 	spin_lock_bh(&conn->nopin_timer_lock);
988 	conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
989 	spin_unlock_bh(&conn->nopin_timer_lock);
990 }
991 
992 void iscsit_handle_nopin_timeout(struct timer_list *t)
993 {
994 	struct iscsi_conn *conn = from_timer(conn, t, nopin_timer);
995 
996 	iscsit_inc_conn_usage_count(conn);
997 
998 	spin_lock_bh(&conn->nopin_timer_lock);
999 	if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1000 		spin_unlock_bh(&conn->nopin_timer_lock);
1001 		iscsit_dec_conn_usage_count(conn);
1002 		return;
1003 	}
1004 	conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1005 	spin_unlock_bh(&conn->nopin_timer_lock);
1006 
1007 	iscsit_add_nopin(conn, 1);
1008 	iscsit_dec_conn_usage_count(conn);
1009 }
1010 
1011 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1012 {
1013 	struct iscsi_session *sess = conn->sess;
1014 	struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1015 
1016 	lockdep_assert_held(&conn->nopin_timer_lock);
1017 
1018 	/*
1019 	* NOPIN timeout is disabled.
1020 	 */
1021 	if (!na->nopin_timeout)
1022 		return;
1023 
1024 	if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1025 		return;
1026 
1027 	conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1028 	conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1029 	mod_timer(&conn->nopin_timer, jiffies + na->nopin_timeout * HZ);
1030 
1031 	pr_debug("Started NOPIN Timer on CID: %d at %u second"
1032 		" interval\n", conn->cid, na->nopin_timeout);
1033 }
1034 
1035 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1036 {
1037 	spin_lock_bh(&conn->nopin_timer_lock);
1038 	__iscsit_start_nopin_timer(conn);
1039 	spin_unlock_bh(&conn->nopin_timer_lock);
1040 }
1041 
1042 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1043 {
1044 	spin_lock_bh(&conn->nopin_timer_lock);
1045 	if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1046 		spin_unlock_bh(&conn->nopin_timer_lock);
1047 		return;
1048 	}
1049 	conn->nopin_timer_flags |= ISCSI_TF_STOP;
1050 	spin_unlock_bh(&conn->nopin_timer_lock);
1051 
1052 	del_timer_sync(&conn->nopin_timer);
1053 
1054 	spin_lock_bh(&conn->nopin_timer_lock);
1055 	conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1056 	spin_unlock_bh(&conn->nopin_timer_lock);
1057 }
1058 
1059 int iscsit_send_tx_data(
1060 	struct iscsi_cmd *cmd,
1061 	struct iscsi_conn *conn,
1062 	int use_misc)
1063 {
1064 	int tx_sent, tx_size;
1065 	u32 iov_count;
1066 	struct kvec *iov;
1067 
1068 send_data:
1069 	tx_size = cmd->tx_size;
1070 
1071 	if (!use_misc) {
1072 		iov = &cmd->iov_data[0];
1073 		iov_count = cmd->iov_data_count;
1074 	} else {
1075 		iov = &cmd->iov_misc[0];
1076 		iov_count = cmd->iov_misc_count;
1077 	}
1078 
1079 	tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1080 	if (tx_size != tx_sent) {
1081 		if (tx_sent == -EAGAIN) {
1082 			pr_err("tx_data() returned -EAGAIN\n");
1083 			goto send_data;
1084 		} else
1085 			return -1;
1086 	}
1087 	cmd->tx_size = 0;
1088 
1089 	return 0;
1090 }
1091 
1092 int iscsit_fe_sendpage_sg(
1093 	struct iscsi_cmd *cmd,
1094 	struct iscsi_conn *conn)
1095 {
1096 	struct scatterlist *sg = cmd->first_data_sg;
1097 	struct kvec iov;
1098 	u32 tx_hdr_size, data_len;
1099 	u32 offset = cmd->first_data_sg_off;
1100 	int tx_sent, iov_off;
1101 
1102 send_hdr:
1103 	tx_hdr_size = ISCSI_HDR_LEN;
1104 	if (conn->conn_ops->HeaderDigest)
1105 		tx_hdr_size += ISCSI_CRC_LEN;
1106 
1107 	iov.iov_base = cmd->pdu;
1108 	iov.iov_len = tx_hdr_size;
1109 
1110 	tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1111 	if (tx_hdr_size != tx_sent) {
1112 		if (tx_sent == -EAGAIN) {
1113 			pr_err("tx_data() returned -EAGAIN\n");
1114 			goto send_hdr;
1115 		}
1116 		return -1;
1117 	}
1118 
1119 	data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1120 	/*
1121 	 * Set iov_off used by padding and data digest tx_data() calls below
1122 	 * in order to determine proper offset into cmd->iov_data[]
1123 	 */
1124 	if (conn->conn_ops->DataDigest) {
1125 		data_len -= ISCSI_CRC_LEN;
1126 		if (cmd->padding)
1127 			iov_off = (cmd->iov_data_count - 2);
1128 		else
1129 			iov_off = (cmd->iov_data_count - 1);
1130 	} else {
1131 		iov_off = (cmd->iov_data_count - 1);
1132 	}
1133 	/*
1134 	 * Perform sendpage() for each page in the scatterlist
1135 	 */
1136 	while (data_len) {
1137 		u32 space = (sg->length - offset);
1138 		u32 sub_len = min_t(u32, data_len, space);
1139 send_pg:
1140 		tx_sent = conn->sock->ops->sendpage(conn->sock,
1141 					sg_page(sg), sg->offset + offset, sub_len, 0);
1142 		if (tx_sent != sub_len) {
1143 			if (tx_sent == -EAGAIN) {
1144 				pr_err("tcp_sendpage() returned"
1145 						" -EAGAIN\n");
1146 				goto send_pg;
1147 			}
1148 
1149 			pr_err("tcp_sendpage() failure: %d\n",
1150 					tx_sent);
1151 			return -1;
1152 		}
1153 
1154 		data_len -= sub_len;
1155 		offset = 0;
1156 		sg = sg_next(sg);
1157 	}
1158 
1159 send_padding:
1160 	if (cmd->padding) {
1161 		struct kvec *iov_p = &cmd->iov_data[iov_off++];
1162 
1163 		tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1164 		if (cmd->padding != tx_sent) {
1165 			if (tx_sent == -EAGAIN) {
1166 				pr_err("tx_data() returned -EAGAIN\n");
1167 				goto send_padding;
1168 			}
1169 			return -1;
1170 		}
1171 	}
1172 
1173 send_datacrc:
1174 	if (conn->conn_ops->DataDigest) {
1175 		struct kvec *iov_d = &cmd->iov_data[iov_off];
1176 
1177 		tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1178 		if (ISCSI_CRC_LEN != tx_sent) {
1179 			if (tx_sent == -EAGAIN) {
1180 				pr_err("tx_data() returned -EAGAIN\n");
1181 				goto send_datacrc;
1182 			}
1183 			return -1;
1184 		}
1185 	}
1186 
1187 	return 0;
1188 }
1189 
1190 /*
1191  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1192  *      back to the Initiator when an expection condition occurs with the
1193  *      errors set in status_class and status_detail.
1194  *
1195  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1196  *      Returns:        0 on success, -1 on error.
1197  */
1198 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1199 {
1200 	struct iscsi_login_rsp *hdr;
1201 	struct iscsi_login *login = conn->conn_login;
1202 
1203 	login->login_failed = 1;
1204 	iscsit_collect_login_stats(conn, status_class, status_detail);
1205 
1206 	memset(&login->rsp[0], 0, ISCSI_HDR_LEN);
1207 
1208 	hdr	= (struct iscsi_login_rsp *)&login->rsp[0];
1209 	hdr->opcode		= ISCSI_OP_LOGIN_RSP;
1210 	hdr->status_class	= status_class;
1211 	hdr->status_detail	= status_detail;
1212 	hdr->itt		= conn->login_itt;
1213 
1214 	return conn->conn_transport->iscsit_put_login_tx(conn, login, 0);
1215 }
1216 
1217 void iscsit_print_session_params(struct iscsi_session *sess)
1218 {
1219 	struct iscsi_conn *conn;
1220 
1221 	pr_debug("-----------------------------[Session Params for"
1222 		" SID: %u]-----------------------------\n", sess->sid);
1223 	spin_lock_bh(&sess->conn_lock);
1224 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1225 		iscsi_dump_conn_ops(conn->conn_ops);
1226 	spin_unlock_bh(&sess->conn_lock);
1227 
1228 	iscsi_dump_sess_ops(sess->sess_ops);
1229 }
1230 
1231 int rx_data(
1232 	struct iscsi_conn *conn,
1233 	struct kvec *iov,
1234 	int iov_count,
1235 	int data)
1236 {
1237 	int rx_loop = 0, total_rx = 0;
1238 	struct msghdr msg;
1239 
1240 	if (!conn || !conn->sock || !conn->conn_ops)
1241 		return -1;
1242 
1243 	memset(&msg, 0, sizeof(struct msghdr));
1244 	iov_iter_kvec(&msg.msg_iter, READ, iov, iov_count, data);
1245 
1246 	while (msg_data_left(&msg)) {
1247 		rx_loop = sock_recvmsg(conn->sock, &msg, MSG_WAITALL);
1248 		if (rx_loop <= 0) {
1249 			pr_debug("rx_loop: %d total_rx: %d\n",
1250 				rx_loop, total_rx);
1251 			return rx_loop;
1252 		}
1253 		total_rx += rx_loop;
1254 		pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1255 				rx_loop, total_rx, data);
1256 	}
1257 
1258 	return total_rx;
1259 }
1260 
1261 int tx_data(
1262 	struct iscsi_conn *conn,
1263 	struct kvec *iov,
1264 	int iov_count,
1265 	int data)
1266 {
1267 	struct msghdr msg;
1268 	int total_tx = 0;
1269 
1270 	if (!conn || !conn->sock || !conn->conn_ops)
1271 		return -1;
1272 
1273 	if (data <= 0) {
1274 		pr_err("Data length is: %d\n", data);
1275 		return -1;
1276 	}
1277 
1278 	memset(&msg, 0, sizeof(struct msghdr));
1279 
1280 	iov_iter_kvec(&msg.msg_iter, WRITE, iov, iov_count, data);
1281 
1282 	while (msg_data_left(&msg)) {
1283 		int tx_loop = sock_sendmsg(conn->sock, &msg);
1284 		if (tx_loop <= 0) {
1285 			pr_debug("tx_loop: %d total_tx %d\n",
1286 				tx_loop, total_tx);
1287 			return tx_loop;
1288 		}
1289 		total_tx += tx_loop;
1290 		pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1291 					tx_loop, total_tx, data);
1292 	}
1293 
1294 	return total_tx;
1295 }
1296 
1297 void iscsit_collect_login_stats(
1298 	struct iscsi_conn *conn,
1299 	u8 status_class,
1300 	u8 status_detail)
1301 {
1302 	struct iscsi_param *intrname = NULL;
1303 	struct iscsi_tiqn *tiqn;
1304 	struct iscsi_login_stats *ls;
1305 
1306 	tiqn = iscsit_snmp_get_tiqn(conn);
1307 	if (!tiqn)
1308 		return;
1309 
1310 	ls = &tiqn->login_stats;
1311 
1312 	spin_lock(&ls->lock);
1313 	if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1314 		ls->accepts++;
1315 	else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1316 		ls->redirects++;
1317 		ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1318 	} else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1319 		 (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1320 		ls->authenticate_fails++;
1321 		ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1322 	} else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1323 		 (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1324 		ls->authorize_fails++;
1325 		ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1326 	} else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1327 		 (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1328 		ls->negotiate_fails++;
1329 		ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1330 	} else {
1331 		ls->other_fails++;
1332 		ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1333 	}
1334 
1335 	/* Save initiator name, ip address and time, if it is a failed login */
1336 	if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1337 		if (conn->param_list)
1338 			intrname = iscsi_find_param_from_key(INITIATORNAME,
1339 							     conn->param_list);
1340 		strlcpy(ls->last_intr_fail_name,
1341 		       (intrname ? intrname->value : "Unknown"),
1342 		       sizeof(ls->last_intr_fail_name));
1343 
1344 		ls->last_intr_fail_ip_family = conn->login_family;
1345 
1346 		ls->last_intr_fail_sockaddr = conn->login_sockaddr;
1347 		ls->last_fail_time = get_jiffies_64();
1348 	}
1349 
1350 	spin_unlock(&ls->lock);
1351 }
1352 
1353 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1354 {
1355 	struct iscsi_portal_group *tpg;
1356 
1357 	if (!conn)
1358 		return NULL;
1359 
1360 	tpg = conn->tpg;
1361 	if (!tpg)
1362 		return NULL;
1363 
1364 	if (!tpg->tpg_tiqn)
1365 		return NULL;
1366 
1367 	return tpg->tpg_tiqn;
1368 }
1369 
1370 void iscsit_fill_cxn_timeout_err_stats(struct iscsi_session *sess)
1371 {
1372 	struct iscsi_portal_group *tpg = sess->tpg;
1373 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
1374 
1375 	if (!tiqn)
1376 		return;
1377 
1378 	spin_lock_bh(&tiqn->sess_err_stats.lock);
1379 	strlcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
1380 			sess->sess_ops->InitiatorName,
1381 			sizeof(tiqn->sess_err_stats.last_sess_fail_rem_name));
1382 	tiqn->sess_err_stats.last_sess_failure_type =
1383 			ISCSI_SESS_ERR_CXN_TIMEOUT;
1384 	tiqn->sess_err_stats.cxn_timeout_errors++;
1385 	atomic_long_inc(&sess->conn_timeout_errors);
1386 	spin_unlock_bh(&tiqn->sess_err_stats.lock);
1387 }
1388