1 /*******************************************************************************
2  * This file contains the iSCSI Target specific utility functions.
3  *
4  * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
5  *
6  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
7  *
8  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
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 
21 #include <linux/list.h>
22 #include <scsi/scsi_tcq.h>
23 #include <scsi/iscsi_proto.h>
24 #include <target/target_core_base.h>
25 #include <target/target_core_transport.h>
26 #include <target/target_core_tmr.h>
27 #include <target/target_core_fabric_ops.h>
28 #include <target/target_core_configfs.h>
29 
30 #include "iscsi_target_core.h"
31 #include "iscsi_target_parameters.h"
32 #include "iscsi_target_seq_pdu_list.h"
33 #include "iscsi_target_datain_values.h"
34 #include "iscsi_target_erl0.h"
35 #include "iscsi_target_erl1.h"
36 #include "iscsi_target_erl2.h"
37 #include "iscsi_target_tpg.h"
38 #include "iscsi_target_tq.h"
39 #include "iscsi_target_util.h"
40 #include "iscsi_target.h"
41 
42 #define PRINT_BUFF(buff, len)					\
43 {								\
44 	int zzz;						\
45 								\
46 	pr_debug("%d:\n", __LINE__);				\
47 	for (zzz = 0; zzz < len; zzz++) {			\
48 		if (zzz % 16 == 0) {				\
49 			if (zzz)				\
50 				pr_debug("\n");			\
51 			pr_debug("%4i: ", zzz);			\
52 		}						\
53 		pr_debug("%02x ", (unsigned char) (buff)[zzz]);	\
54 	}							\
55 	if ((len + 1) % 16)					\
56 		pr_debug("\n");					\
57 }
58 
59 extern struct list_head g_tiqn_list;
60 extern spinlock_t tiqn_lock;
61 
62 /*
63  *	Called with cmd->r2t_lock held.
64  */
65 int iscsit_add_r2t_to_list(
66 	struct iscsi_cmd *cmd,
67 	u32 offset,
68 	u32 xfer_len,
69 	int recovery,
70 	u32 r2t_sn)
71 {
72 	struct iscsi_r2t *r2t;
73 
74 	r2t = kmem_cache_zalloc(lio_r2t_cache, GFP_ATOMIC);
75 	if (!r2t) {
76 		pr_err("Unable to allocate memory for struct iscsi_r2t.\n");
77 		return -1;
78 	}
79 	INIT_LIST_HEAD(&r2t->r2t_list);
80 
81 	r2t->recovery_r2t = recovery;
82 	r2t->r2t_sn = (!r2t_sn) ? cmd->r2t_sn++ : r2t_sn;
83 	r2t->offset = offset;
84 	r2t->xfer_len = xfer_len;
85 	list_add_tail(&r2t->r2t_list, &cmd->cmd_r2t_list);
86 	spin_unlock_bh(&cmd->r2t_lock);
87 
88 	iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
89 
90 	spin_lock_bh(&cmd->r2t_lock);
91 	return 0;
92 }
93 
94 struct iscsi_r2t *iscsit_get_r2t_for_eos(
95 	struct iscsi_cmd *cmd,
96 	u32 offset,
97 	u32 length)
98 {
99 	struct iscsi_r2t *r2t;
100 
101 	spin_lock_bh(&cmd->r2t_lock);
102 	list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
103 		if ((r2t->offset <= offset) &&
104 		    (r2t->offset + r2t->xfer_len) >= (offset + length)) {
105 			spin_unlock_bh(&cmd->r2t_lock);
106 			return r2t;
107 		}
108 	}
109 	spin_unlock_bh(&cmd->r2t_lock);
110 
111 	pr_err("Unable to locate R2T for Offset: %u, Length:"
112 			" %u\n", offset, length);
113 	return NULL;
114 }
115 
116 struct iscsi_r2t *iscsit_get_r2t_from_list(struct iscsi_cmd *cmd)
117 {
118 	struct iscsi_r2t *r2t;
119 
120 	spin_lock_bh(&cmd->r2t_lock);
121 	list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
122 		if (!r2t->sent_r2t) {
123 			spin_unlock_bh(&cmd->r2t_lock);
124 			return r2t;
125 		}
126 	}
127 	spin_unlock_bh(&cmd->r2t_lock);
128 
129 	pr_err("Unable to locate next R2T to send for ITT:"
130 			" 0x%08x.\n", cmd->init_task_tag);
131 	return NULL;
132 }
133 
134 /*
135  *	Called with cmd->r2t_lock held.
136  */
137 void iscsit_free_r2t(struct iscsi_r2t *r2t, struct iscsi_cmd *cmd)
138 {
139 	list_del(&r2t->r2t_list);
140 	kmem_cache_free(lio_r2t_cache, r2t);
141 }
142 
143 void iscsit_free_r2ts_from_list(struct iscsi_cmd *cmd)
144 {
145 	struct iscsi_r2t *r2t, *r2t_tmp;
146 
147 	spin_lock_bh(&cmd->r2t_lock);
148 	list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list)
149 		iscsit_free_r2t(r2t, cmd);
150 	spin_unlock_bh(&cmd->r2t_lock);
151 }
152 
153 /*
154  * May be called from software interrupt (timer) context for allocating
155  * iSCSI NopINs.
156  */
157 struct iscsi_cmd *iscsit_allocate_cmd(struct iscsi_conn *conn, gfp_t gfp_mask)
158 {
159 	struct iscsi_cmd *cmd;
160 
161 	cmd = kmem_cache_zalloc(lio_cmd_cache, gfp_mask);
162 	if (!cmd) {
163 		pr_err("Unable to allocate memory for struct iscsi_cmd.\n");
164 		return NULL;
165 	}
166 
167 	cmd->conn	= conn;
168 	INIT_LIST_HEAD(&cmd->i_list);
169 	INIT_LIST_HEAD(&cmd->datain_list);
170 	INIT_LIST_HEAD(&cmd->cmd_r2t_list);
171 	init_completion(&cmd->reject_comp);
172 	spin_lock_init(&cmd->datain_lock);
173 	spin_lock_init(&cmd->dataout_timeout_lock);
174 	spin_lock_init(&cmd->istate_lock);
175 	spin_lock_init(&cmd->error_lock);
176 	spin_lock_init(&cmd->r2t_lock);
177 
178 	return cmd;
179 }
180 
181 /*
182  * Called from iscsi_handle_scsi_cmd()
183  */
184 struct iscsi_cmd *iscsit_allocate_se_cmd(
185 	struct iscsi_conn *conn,
186 	u32 data_length,
187 	int data_direction,
188 	int iscsi_task_attr)
189 {
190 	struct iscsi_cmd *cmd;
191 	struct se_cmd *se_cmd;
192 	int sam_task_attr;
193 
194 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
195 	if (!cmd)
196 		return NULL;
197 
198 	cmd->data_direction = data_direction;
199 	cmd->data_length = data_length;
200 	/*
201 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
202 	 */
203 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
204 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
205 		sam_task_attr = MSG_SIMPLE_TAG;
206 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
207 		sam_task_attr = MSG_ORDERED_TAG;
208 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
209 		sam_task_attr = MSG_HEAD_TAG;
210 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
211 		sam_task_attr = MSG_ACA_TAG;
212 	else {
213 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
214 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
215 		sam_task_attr = MSG_SIMPLE_TAG;
216 	}
217 
218 	se_cmd = &cmd->se_cmd;
219 	/*
220 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
221 	 */
222 	transport_init_se_cmd(se_cmd, &lio_target_fabric_configfs->tf_ops,
223 			conn->sess->se_sess, data_length, data_direction,
224 			sam_task_attr, &cmd->sense_buffer[0]);
225 	return cmd;
226 }
227 
228 struct iscsi_cmd *iscsit_allocate_se_cmd_for_tmr(
229 	struct iscsi_conn *conn,
230 	u8 function)
231 {
232 	struct iscsi_cmd *cmd;
233 	struct se_cmd *se_cmd;
234 	u8 tcm_function;
235 
236 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
237 	if (!cmd)
238 		return NULL;
239 
240 	cmd->data_direction = DMA_NONE;
241 
242 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
243 	if (!cmd->tmr_req) {
244 		pr_err("Unable to allocate memory for"
245 			" Task Management command!\n");
246 		goto out;
247 	}
248 	/*
249 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
250 	 * LIO-Target $FABRIC_MOD
251 	 */
252 	if (function == ISCSI_TM_FUNC_TASK_REASSIGN)
253 		return cmd;
254 
255 	se_cmd = &cmd->se_cmd;
256 	/*
257 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
258 	 */
259 	transport_init_se_cmd(se_cmd, &lio_target_fabric_configfs->tf_ops,
260 				conn->sess->se_sess, 0, DMA_NONE,
261 				MSG_SIMPLE_TAG, &cmd->sense_buffer[0]);
262 
263 	switch (function) {
264 	case ISCSI_TM_FUNC_ABORT_TASK:
265 		tcm_function = TMR_ABORT_TASK;
266 		break;
267 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
268 		tcm_function = TMR_ABORT_TASK_SET;
269 		break;
270 	case ISCSI_TM_FUNC_CLEAR_ACA:
271 		tcm_function = TMR_CLEAR_ACA;
272 		break;
273 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
274 		tcm_function = TMR_CLEAR_TASK_SET;
275 		break;
276 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
277 		tcm_function = TMR_LUN_RESET;
278 		break;
279 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
280 		tcm_function = TMR_TARGET_WARM_RESET;
281 		break;
282 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
283 		tcm_function = TMR_TARGET_COLD_RESET;
284 		break;
285 	default:
286 		pr_err("Unknown iSCSI TMR Function:"
287 			" 0x%02x\n", function);
288 		goto out;
289 	}
290 
291 	se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd,
292 				(void *)cmd->tmr_req, tcm_function);
293 	if (!se_cmd->se_tmr_req)
294 		goto out;
295 
296 	cmd->tmr_req->se_tmr_req = se_cmd->se_tmr_req;
297 
298 	return cmd;
299 out:
300 	iscsit_release_cmd(cmd);
301 	return NULL;
302 }
303 
304 int iscsit_decide_list_to_build(
305 	struct iscsi_cmd *cmd,
306 	u32 immediate_data_length)
307 {
308 	struct iscsi_build_list bl;
309 	struct iscsi_conn *conn = cmd->conn;
310 	struct iscsi_session *sess = conn->sess;
311 	struct iscsi_node_attrib *na;
312 
313 	if (sess->sess_ops->DataSequenceInOrder &&
314 	    sess->sess_ops->DataPDUInOrder)
315 		return 0;
316 
317 	if (cmd->data_direction == DMA_NONE)
318 		return 0;
319 
320 	na = iscsit_tpg_get_node_attrib(sess);
321 	memset(&bl, 0, sizeof(struct iscsi_build_list));
322 
323 	if (cmd->data_direction == DMA_FROM_DEVICE) {
324 		bl.data_direction = ISCSI_PDU_READ;
325 		bl.type = PDULIST_NORMAL;
326 		if (na->random_datain_pdu_offsets)
327 			bl.randomize |= RANDOM_DATAIN_PDU_OFFSETS;
328 		if (na->random_datain_seq_offsets)
329 			bl.randomize |= RANDOM_DATAIN_SEQ_OFFSETS;
330 	} else {
331 		bl.data_direction = ISCSI_PDU_WRITE;
332 		bl.immediate_data_length = immediate_data_length;
333 		if (na->random_r2t_offsets)
334 			bl.randomize |= RANDOM_R2T_OFFSETS;
335 
336 		if (!cmd->immediate_data && !cmd->unsolicited_data)
337 			bl.type = PDULIST_NORMAL;
338 		else if (cmd->immediate_data && !cmd->unsolicited_data)
339 			bl.type = PDULIST_IMMEDIATE;
340 		else if (!cmd->immediate_data && cmd->unsolicited_data)
341 			bl.type = PDULIST_UNSOLICITED;
342 		else if (cmd->immediate_data && cmd->unsolicited_data)
343 			bl.type = PDULIST_IMMEDIATE_AND_UNSOLICITED;
344 	}
345 
346 	return iscsit_do_build_list(cmd, &bl);
347 }
348 
349 struct iscsi_seq *iscsit_get_seq_holder_for_datain(
350 	struct iscsi_cmd *cmd,
351 	u32 seq_send_order)
352 {
353 	u32 i;
354 
355 	for (i = 0; i < cmd->seq_count; i++)
356 		if (cmd->seq_list[i].seq_send_order == seq_send_order)
357 			return &cmd->seq_list[i];
358 
359 	return NULL;
360 }
361 
362 struct iscsi_seq *iscsit_get_seq_holder_for_r2t(struct iscsi_cmd *cmd)
363 {
364 	u32 i;
365 
366 	if (!cmd->seq_list) {
367 		pr_err("struct iscsi_cmd->seq_list is NULL!\n");
368 		return NULL;
369 	}
370 
371 	for (i = 0; i < cmd->seq_count; i++) {
372 		if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
373 			continue;
374 		if (cmd->seq_list[i].seq_send_order == cmd->seq_send_order) {
375 			cmd->seq_send_order++;
376 			return &cmd->seq_list[i];
377 		}
378 	}
379 
380 	return NULL;
381 }
382 
383 struct iscsi_r2t *iscsit_get_holder_for_r2tsn(
384 	struct iscsi_cmd *cmd,
385 	u32 r2t_sn)
386 {
387 	struct iscsi_r2t *r2t;
388 
389 	spin_lock_bh(&cmd->r2t_lock);
390 	list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
391 		if (r2t->r2t_sn == r2t_sn) {
392 			spin_unlock_bh(&cmd->r2t_lock);
393 			return r2t;
394 		}
395 	}
396 	spin_unlock_bh(&cmd->r2t_lock);
397 
398 	return NULL;
399 }
400 
401 static inline int iscsit_check_received_cmdsn(struct iscsi_session *sess, u32 cmdsn)
402 {
403 	int ret;
404 
405 	/*
406 	 * This is the proper method of checking received CmdSN against
407 	 * ExpCmdSN and MaxCmdSN values, as well as accounting for out
408 	 * or order CmdSNs due to multiple connection sessions and/or
409 	 * CRC failures.
410 	 */
411 	if (iscsi_sna_gt(cmdsn, sess->max_cmd_sn)) {
412 		pr_err("Received CmdSN: 0x%08x is greater than"
413 		       " MaxCmdSN: 0x%08x, protocol error.\n", cmdsn,
414 		       sess->max_cmd_sn);
415 		ret = CMDSN_ERROR_CANNOT_RECOVER;
416 
417 	} else if (cmdsn == sess->exp_cmd_sn) {
418 		sess->exp_cmd_sn++;
419 		pr_debug("Received CmdSN matches ExpCmdSN,"
420 		      " incremented ExpCmdSN to: 0x%08x\n",
421 		      sess->exp_cmd_sn);
422 		ret = CMDSN_NORMAL_OPERATION;
423 
424 	} else if (iscsi_sna_gt(cmdsn, sess->exp_cmd_sn)) {
425 		pr_debug("Received CmdSN: 0x%08x is greater"
426 		      " than ExpCmdSN: 0x%08x, not acknowledging.\n",
427 		      cmdsn, sess->exp_cmd_sn);
428 		ret = CMDSN_HIGHER_THAN_EXP;
429 
430 	} else {
431 		pr_err("Received CmdSN: 0x%08x is less than"
432 		       " ExpCmdSN: 0x%08x, ignoring.\n", cmdsn,
433 		       sess->exp_cmd_sn);
434 		ret = CMDSN_LOWER_THAN_EXP;
435 	}
436 
437 	return ret;
438 }
439 
440 /*
441  * Commands may be received out of order if MC/S is in use.
442  * Ensure they are executed in CmdSN order.
443  */
444 int iscsit_sequence_cmd(
445 	struct iscsi_conn *conn,
446 	struct iscsi_cmd *cmd,
447 	u32 cmdsn)
448 {
449 	int ret;
450 	int cmdsn_ret;
451 
452 	mutex_lock(&conn->sess->cmdsn_mutex);
453 
454 	cmdsn_ret = iscsit_check_received_cmdsn(conn->sess, cmdsn);
455 	switch (cmdsn_ret) {
456 	case CMDSN_NORMAL_OPERATION:
457 		ret = iscsit_execute_cmd(cmd, 0);
458 		if ((ret >= 0) && !list_empty(&conn->sess->sess_ooo_cmdsn_list))
459 			iscsit_execute_ooo_cmdsns(conn->sess);
460 		break;
461 	case CMDSN_HIGHER_THAN_EXP:
462 		ret = iscsit_handle_ooo_cmdsn(conn->sess, cmd, cmdsn);
463 		break;
464 	case CMDSN_LOWER_THAN_EXP:
465 		cmd->i_state = ISTATE_REMOVE;
466 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
467 		ret = cmdsn_ret;
468 		break;
469 	default:
470 		ret = cmdsn_ret;
471 		break;
472 	}
473 	mutex_unlock(&conn->sess->cmdsn_mutex);
474 
475 	return ret;
476 }
477 
478 int iscsit_check_unsolicited_dataout(struct iscsi_cmd *cmd, unsigned char *buf)
479 {
480 	struct iscsi_conn *conn = cmd->conn;
481 	struct se_cmd *se_cmd = &cmd->se_cmd;
482 	struct iscsi_data *hdr = (struct iscsi_data *) buf;
483 	u32 payload_length = ntoh24(hdr->dlength);
484 
485 	if (conn->sess->sess_ops->InitialR2T) {
486 		pr_err("Received unexpected unsolicited data"
487 			" while InitialR2T=Yes, protocol error.\n");
488 		transport_send_check_condition_and_sense(se_cmd,
489 				TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
490 		return -1;
491 	}
492 
493 	if ((cmd->first_burst_len + payload_length) >
494 	     conn->sess->sess_ops->FirstBurstLength) {
495 		pr_err("Total %u bytes exceeds FirstBurstLength: %u"
496 			" for this Unsolicited DataOut Burst.\n",
497 			(cmd->first_burst_len + payload_length),
498 				conn->sess->sess_ops->FirstBurstLength);
499 		transport_send_check_condition_and_sense(se_cmd,
500 				TCM_INCORRECT_AMOUNT_OF_DATA, 0);
501 		return -1;
502 	}
503 
504 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))
505 		return 0;
506 
507 	if (((cmd->first_burst_len + payload_length) != cmd->data_length) &&
508 	    ((cmd->first_burst_len + payload_length) !=
509 	      conn->sess->sess_ops->FirstBurstLength)) {
510 		pr_err("Unsolicited non-immediate data received %u"
511 			" does not equal FirstBurstLength: %u, and does"
512 			" not equal ExpXferLen %u.\n",
513 			(cmd->first_burst_len + payload_length),
514 			conn->sess->sess_ops->FirstBurstLength, cmd->data_length);
515 		transport_send_check_condition_and_sense(se_cmd,
516 				TCM_INCORRECT_AMOUNT_OF_DATA, 0);
517 		return -1;
518 	}
519 	return 0;
520 }
521 
522 struct iscsi_cmd *iscsit_find_cmd_from_itt(
523 	struct iscsi_conn *conn,
524 	u32 init_task_tag)
525 {
526 	struct iscsi_cmd *cmd;
527 
528 	spin_lock_bh(&conn->cmd_lock);
529 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_list) {
530 		if (cmd->init_task_tag == init_task_tag) {
531 			spin_unlock_bh(&conn->cmd_lock);
532 			return cmd;
533 		}
534 	}
535 	spin_unlock_bh(&conn->cmd_lock);
536 
537 	pr_err("Unable to locate ITT: 0x%08x on CID: %hu",
538 			init_task_tag, conn->cid);
539 	return NULL;
540 }
541 
542 struct iscsi_cmd *iscsit_find_cmd_from_itt_or_dump(
543 	struct iscsi_conn *conn,
544 	u32 init_task_tag,
545 	u32 length)
546 {
547 	struct iscsi_cmd *cmd;
548 
549 	spin_lock_bh(&conn->cmd_lock);
550 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_list) {
551 		if (cmd->init_task_tag == init_task_tag) {
552 			spin_unlock_bh(&conn->cmd_lock);
553 			return cmd;
554 		}
555 	}
556 	spin_unlock_bh(&conn->cmd_lock);
557 
558 	pr_err("Unable to locate ITT: 0x%08x on CID: %hu,"
559 			" dumping payload\n", init_task_tag, conn->cid);
560 	if (length)
561 		iscsit_dump_data_payload(conn, length, 1);
562 
563 	return NULL;
564 }
565 
566 struct iscsi_cmd *iscsit_find_cmd_from_ttt(
567 	struct iscsi_conn *conn,
568 	u32 targ_xfer_tag)
569 {
570 	struct iscsi_cmd *cmd = NULL;
571 
572 	spin_lock_bh(&conn->cmd_lock);
573 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_list) {
574 		if (cmd->targ_xfer_tag == targ_xfer_tag) {
575 			spin_unlock_bh(&conn->cmd_lock);
576 			return cmd;
577 		}
578 	}
579 	spin_unlock_bh(&conn->cmd_lock);
580 
581 	pr_err("Unable to locate TTT: 0x%08x on CID: %hu\n",
582 			targ_xfer_tag, conn->cid);
583 	return NULL;
584 }
585 
586 int iscsit_find_cmd_for_recovery(
587 	struct iscsi_session *sess,
588 	struct iscsi_cmd **cmd_ptr,
589 	struct iscsi_conn_recovery **cr_ptr,
590 	u32 init_task_tag)
591 {
592 	struct iscsi_cmd *cmd = NULL;
593 	struct iscsi_conn_recovery *cr;
594 	/*
595 	 * Scan through the inactive connection recovery list's command list.
596 	 * If init_task_tag matches the command is still alligent.
597 	 */
598 	spin_lock(&sess->cr_i_lock);
599 	list_for_each_entry(cr, &sess->cr_inactive_list, cr_list) {
600 		spin_lock(&cr->conn_recovery_cmd_lock);
601 		list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_list) {
602 			if (cmd->init_task_tag == init_task_tag) {
603 				spin_unlock(&cr->conn_recovery_cmd_lock);
604 				spin_unlock(&sess->cr_i_lock);
605 
606 				*cr_ptr = cr;
607 				*cmd_ptr = cmd;
608 				return -2;
609 			}
610 		}
611 		spin_unlock(&cr->conn_recovery_cmd_lock);
612 	}
613 	spin_unlock(&sess->cr_i_lock);
614 	/*
615 	 * Scan through the active connection recovery list's command list.
616 	 * If init_task_tag matches the command is ready to be reassigned.
617 	 */
618 	spin_lock(&sess->cr_a_lock);
619 	list_for_each_entry(cr, &sess->cr_active_list, cr_list) {
620 		spin_lock(&cr->conn_recovery_cmd_lock);
621 		list_for_each_entry(cmd, &cr->conn_recovery_cmd_list, i_list) {
622 			if (cmd->init_task_tag == init_task_tag) {
623 				spin_unlock(&cr->conn_recovery_cmd_lock);
624 				spin_unlock(&sess->cr_a_lock);
625 
626 				*cr_ptr = cr;
627 				*cmd_ptr = cmd;
628 				return 0;
629 			}
630 		}
631 		spin_unlock(&cr->conn_recovery_cmd_lock);
632 	}
633 	spin_unlock(&sess->cr_a_lock);
634 
635 	return -1;
636 }
637 
638 void iscsit_add_cmd_to_immediate_queue(
639 	struct iscsi_cmd *cmd,
640 	struct iscsi_conn *conn,
641 	u8 state)
642 {
643 	struct iscsi_queue_req *qr;
644 
645 	qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
646 	if (!qr) {
647 		pr_err("Unable to allocate memory for"
648 				" struct iscsi_queue_req\n");
649 		return;
650 	}
651 	INIT_LIST_HEAD(&qr->qr_list);
652 	qr->cmd = cmd;
653 	qr->state = state;
654 
655 	spin_lock_bh(&conn->immed_queue_lock);
656 	list_add_tail(&qr->qr_list, &conn->immed_queue_list);
657 	atomic_inc(&cmd->immed_queue_count);
658 	atomic_set(&conn->check_immediate_queue, 1);
659 	spin_unlock_bh(&conn->immed_queue_lock);
660 
661 	wake_up_process(conn->thread_set->tx_thread);
662 }
663 
664 struct iscsi_queue_req *iscsit_get_cmd_from_immediate_queue(struct iscsi_conn *conn)
665 {
666 	struct iscsi_queue_req *qr;
667 
668 	spin_lock_bh(&conn->immed_queue_lock);
669 	if (list_empty(&conn->immed_queue_list)) {
670 		spin_unlock_bh(&conn->immed_queue_lock);
671 		return NULL;
672 	}
673 	list_for_each_entry(qr, &conn->immed_queue_list, qr_list)
674 		break;
675 
676 	list_del(&qr->qr_list);
677 	if (qr->cmd)
678 		atomic_dec(&qr->cmd->immed_queue_count);
679 	spin_unlock_bh(&conn->immed_queue_lock);
680 
681 	return qr;
682 }
683 
684 static void iscsit_remove_cmd_from_immediate_queue(
685 	struct iscsi_cmd *cmd,
686 	struct iscsi_conn *conn)
687 {
688 	struct iscsi_queue_req *qr, *qr_tmp;
689 
690 	spin_lock_bh(&conn->immed_queue_lock);
691 	if (!atomic_read(&cmd->immed_queue_count)) {
692 		spin_unlock_bh(&conn->immed_queue_lock);
693 		return;
694 	}
695 
696 	list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
697 		if (qr->cmd != cmd)
698 			continue;
699 
700 		atomic_dec(&qr->cmd->immed_queue_count);
701 		list_del(&qr->qr_list);
702 		kmem_cache_free(lio_qr_cache, qr);
703 	}
704 	spin_unlock_bh(&conn->immed_queue_lock);
705 
706 	if (atomic_read(&cmd->immed_queue_count)) {
707 		pr_err("ITT: 0x%08x immed_queue_count: %d\n",
708 			cmd->init_task_tag,
709 			atomic_read(&cmd->immed_queue_count));
710 	}
711 }
712 
713 void iscsit_add_cmd_to_response_queue(
714 	struct iscsi_cmd *cmd,
715 	struct iscsi_conn *conn,
716 	u8 state)
717 {
718 	struct iscsi_queue_req *qr;
719 
720 	qr = kmem_cache_zalloc(lio_qr_cache, GFP_ATOMIC);
721 	if (!qr) {
722 		pr_err("Unable to allocate memory for"
723 			" struct iscsi_queue_req\n");
724 		return;
725 	}
726 	INIT_LIST_HEAD(&qr->qr_list);
727 	qr->cmd = cmd;
728 	qr->state = state;
729 
730 	spin_lock_bh(&conn->response_queue_lock);
731 	list_add_tail(&qr->qr_list, &conn->response_queue_list);
732 	atomic_inc(&cmd->response_queue_count);
733 	spin_unlock_bh(&conn->response_queue_lock);
734 
735 	wake_up_process(conn->thread_set->tx_thread);
736 }
737 
738 struct iscsi_queue_req *iscsit_get_cmd_from_response_queue(struct iscsi_conn *conn)
739 {
740 	struct iscsi_queue_req *qr;
741 
742 	spin_lock_bh(&conn->response_queue_lock);
743 	if (list_empty(&conn->response_queue_list)) {
744 		spin_unlock_bh(&conn->response_queue_lock);
745 		return NULL;
746 	}
747 
748 	list_for_each_entry(qr, &conn->response_queue_list, qr_list)
749 		break;
750 
751 	list_del(&qr->qr_list);
752 	if (qr->cmd)
753 		atomic_dec(&qr->cmd->response_queue_count);
754 	spin_unlock_bh(&conn->response_queue_lock);
755 
756 	return qr;
757 }
758 
759 static void iscsit_remove_cmd_from_response_queue(
760 	struct iscsi_cmd *cmd,
761 	struct iscsi_conn *conn)
762 {
763 	struct iscsi_queue_req *qr, *qr_tmp;
764 
765 	spin_lock_bh(&conn->response_queue_lock);
766 	if (!atomic_read(&cmd->response_queue_count)) {
767 		spin_unlock_bh(&conn->response_queue_lock);
768 		return;
769 	}
770 
771 	list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
772 				qr_list) {
773 		if (qr->cmd != cmd)
774 			continue;
775 
776 		atomic_dec(&qr->cmd->response_queue_count);
777 		list_del(&qr->qr_list);
778 		kmem_cache_free(lio_qr_cache, qr);
779 	}
780 	spin_unlock_bh(&conn->response_queue_lock);
781 
782 	if (atomic_read(&cmd->response_queue_count)) {
783 		pr_err("ITT: 0x%08x response_queue_count: %d\n",
784 			cmd->init_task_tag,
785 			atomic_read(&cmd->response_queue_count));
786 	}
787 }
788 
789 void iscsit_free_queue_reqs_for_conn(struct iscsi_conn *conn)
790 {
791 	struct iscsi_queue_req *qr, *qr_tmp;
792 
793 	spin_lock_bh(&conn->immed_queue_lock);
794 	list_for_each_entry_safe(qr, qr_tmp, &conn->immed_queue_list, qr_list) {
795 		list_del(&qr->qr_list);
796 		if (qr->cmd)
797 			atomic_dec(&qr->cmd->immed_queue_count);
798 
799 		kmem_cache_free(lio_qr_cache, qr);
800 	}
801 	spin_unlock_bh(&conn->immed_queue_lock);
802 
803 	spin_lock_bh(&conn->response_queue_lock);
804 	list_for_each_entry_safe(qr, qr_tmp, &conn->response_queue_list,
805 			qr_list) {
806 		list_del(&qr->qr_list);
807 		if (qr->cmd)
808 			atomic_dec(&qr->cmd->response_queue_count);
809 
810 		kmem_cache_free(lio_qr_cache, qr);
811 	}
812 	spin_unlock_bh(&conn->response_queue_lock);
813 }
814 
815 void iscsit_release_cmd(struct iscsi_cmd *cmd)
816 {
817 	struct iscsi_conn *conn = cmd->conn;
818 	int i;
819 
820 	iscsit_free_r2ts_from_list(cmd);
821 	iscsit_free_all_datain_reqs(cmd);
822 
823 	kfree(cmd->buf_ptr);
824 	kfree(cmd->pdu_list);
825 	kfree(cmd->seq_list);
826 	kfree(cmd->tmr_req);
827 	kfree(cmd->iov_data);
828 
829 	for (i = 0; i < cmd->t_mem_sg_nents; i++)
830 		__free_page(sg_page(&cmd->t_mem_sg[i]));
831 
832 	kfree(cmd->t_mem_sg);
833 
834 	if (conn) {
835 		iscsit_remove_cmd_from_immediate_queue(cmd, conn);
836 		iscsit_remove_cmd_from_response_queue(cmd, conn);
837 	}
838 
839 	kmem_cache_free(lio_cmd_cache, cmd);
840 }
841 
842 int iscsit_check_session_usage_count(struct iscsi_session *sess)
843 {
844 	spin_lock_bh(&sess->session_usage_lock);
845 	if (sess->session_usage_count != 0) {
846 		sess->session_waiting_on_uc = 1;
847 		spin_unlock_bh(&sess->session_usage_lock);
848 		if (in_interrupt())
849 			return 2;
850 
851 		wait_for_completion(&sess->session_waiting_on_uc_comp);
852 		return 1;
853 	}
854 	spin_unlock_bh(&sess->session_usage_lock);
855 
856 	return 0;
857 }
858 
859 void iscsit_dec_session_usage_count(struct iscsi_session *sess)
860 {
861 	spin_lock_bh(&sess->session_usage_lock);
862 	sess->session_usage_count--;
863 
864 	if (!sess->session_usage_count && sess->session_waiting_on_uc)
865 		complete(&sess->session_waiting_on_uc_comp);
866 
867 	spin_unlock_bh(&sess->session_usage_lock);
868 }
869 
870 void iscsit_inc_session_usage_count(struct iscsi_session *sess)
871 {
872 	spin_lock_bh(&sess->session_usage_lock);
873 	sess->session_usage_count++;
874 	spin_unlock_bh(&sess->session_usage_lock);
875 }
876 
877 /*
878  *	Setup conn->if_marker and conn->of_marker values based upon
879  *	the initial marker-less interval. (see iSCSI v19 A.2)
880  */
881 int iscsit_set_sync_and_steering_values(struct iscsi_conn *conn)
882 {
883 	int login_ifmarker_count = 0, login_ofmarker_count = 0, next_marker = 0;
884 	/*
885 	 * IFMarkInt and OFMarkInt are negotiated as 32-bit words.
886 	 */
887 	u32 IFMarkInt = (conn->conn_ops->IFMarkInt * 4);
888 	u32 OFMarkInt = (conn->conn_ops->OFMarkInt * 4);
889 
890 	if (conn->conn_ops->OFMarker) {
891 		/*
892 		 * Account for the first Login Command received not
893 		 * via iscsi_recv_msg().
894 		 */
895 		conn->of_marker += ISCSI_HDR_LEN;
896 		if (conn->of_marker <= OFMarkInt) {
897 			conn->of_marker = (OFMarkInt - conn->of_marker);
898 		} else {
899 			login_ofmarker_count = (conn->of_marker / OFMarkInt);
900 			next_marker = (OFMarkInt * (login_ofmarker_count + 1)) +
901 					(login_ofmarker_count * MARKER_SIZE);
902 			conn->of_marker = (next_marker - conn->of_marker);
903 		}
904 		conn->of_marker_offset = 0;
905 		pr_debug("Setting OFMarker value to %u based on Initial"
906 			" Markerless Interval.\n", conn->of_marker);
907 	}
908 
909 	if (conn->conn_ops->IFMarker) {
910 		if (conn->if_marker <= IFMarkInt) {
911 			conn->if_marker = (IFMarkInt - conn->if_marker);
912 		} else {
913 			login_ifmarker_count = (conn->if_marker / IFMarkInt);
914 			next_marker = (IFMarkInt * (login_ifmarker_count + 1)) +
915 					(login_ifmarker_count * MARKER_SIZE);
916 			conn->if_marker = (next_marker - conn->if_marker);
917 		}
918 		pr_debug("Setting IFMarker value to %u based on Initial"
919 			" Markerless Interval.\n", conn->if_marker);
920 	}
921 
922 	return 0;
923 }
924 
925 struct iscsi_conn *iscsit_get_conn_from_cid(struct iscsi_session *sess, u16 cid)
926 {
927 	struct iscsi_conn *conn;
928 
929 	spin_lock_bh(&sess->conn_lock);
930 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
931 		if ((conn->cid == cid) &&
932 		    (conn->conn_state == TARG_CONN_STATE_LOGGED_IN)) {
933 			iscsit_inc_conn_usage_count(conn);
934 			spin_unlock_bh(&sess->conn_lock);
935 			return conn;
936 		}
937 	}
938 	spin_unlock_bh(&sess->conn_lock);
939 
940 	return NULL;
941 }
942 
943 struct iscsi_conn *iscsit_get_conn_from_cid_rcfr(struct iscsi_session *sess, u16 cid)
944 {
945 	struct iscsi_conn *conn;
946 
947 	spin_lock_bh(&sess->conn_lock);
948 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
949 		if (conn->cid == cid) {
950 			iscsit_inc_conn_usage_count(conn);
951 			spin_lock(&conn->state_lock);
952 			atomic_set(&conn->connection_wait_rcfr, 1);
953 			spin_unlock(&conn->state_lock);
954 			spin_unlock_bh(&sess->conn_lock);
955 			return conn;
956 		}
957 	}
958 	spin_unlock_bh(&sess->conn_lock);
959 
960 	return NULL;
961 }
962 
963 void iscsit_check_conn_usage_count(struct iscsi_conn *conn)
964 {
965 	spin_lock_bh(&conn->conn_usage_lock);
966 	if (conn->conn_usage_count != 0) {
967 		conn->conn_waiting_on_uc = 1;
968 		spin_unlock_bh(&conn->conn_usage_lock);
969 
970 		wait_for_completion(&conn->conn_waiting_on_uc_comp);
971 		return;
972 	}
973 	spin_unlock_bh(&conn->conn_usage_lock);
974 }
975 
976 void iscsit_dec_conn_usage_count(struct iscsi_conn *conn)
977 {
978 	spin_lock_bh(&conn->conn_usage_lock);
979 	conn->conn_usage_count--;
980 
981 	if (!conn->conn_usage_count && conn->conn_waiting_on_uc)
982 		complete(&conn->conn_waiting_on_uc_comp);
983 
984 	spin_unlock_bh(&conn->conn_usage_lock);
985 }
986 
987 void iscsit_inc_conn_usage_count(struct iscsi_conn *conn)
988 {
989 	spin_lock_bh(&conn->conn_usage_lock);
990 	conn->conn_usage_count++;
991 	spin_unlock_bh(&conn->conn_usage_lock);
992 }
993 
994 static int iscsit_add_nopin(struct iscsi_conn *conn, int want_response)
995 {
996 	u8 state;
997 	struct iscsi_cmd *cmd;
998 
999 	cmd = iscsit_allocate_cmd(conn, GFP_ATOMIC);
1000 	if (!cmd)
1001 		return -1;
1002 
1003 	cmd->iscsi_opcode = ISCSI_OP_NOOP_IN;
1004 	state = (want_response) ? ISTATE_SEND_NOPIN_WANT_RESPONSE :
1005 				ISTATE_SEND_NOPIN_NO_RESPONSE;
1006 	cmd->init_task_tag = 0xFFFFFFFF;
1007 	spin_lock_bh(&conn->sess->ttt_lock);
1008 	cmd->targ_xfer_tag = (want_response) ? conn->sess->targ_xfer_tag++ :
1009 			0xFFFFFFFF;
1010 	if (want_response && (cmd->targ_xfer_tag == 0xFFFFFFFF))
1011 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
1012 	spin_unlock_bh(&conn->sess->ttt_lock);
1013 
1014 	spin_lock_bh(&conn->cmd_lock);
1015 	list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
1016 	spin_unlock_bh(&conn->cmd_lock);
1017 
1018 	if (want_response)
1019 		iscsit_start_nopin_response_timer(conn);
1020 	iscsit_add_cmd_to_immediate_queue(cmd, conn, state);
1021 
1022 	return 0;
1023 }
1024 
1025 static void iscsit_handle_nopin_response_timeout(unsigned long data)
1026 {
1027 	struct iscsi_conn *conn = (struct iscsi_conn *) data;
1028 
1029 	iscsit_inc_conn_usage_count(conn);
1030 
1031 	spin_lock_bh(&conn->nopin_timer_lock);
1032 	if (conn->nopin_response_timer_flags & ISCSI_TF_STOP) {
1033 		spin_unlock_bh(&conn->nopin_timer_lock);
1034 		iscsit_dec_conn_usage_count(conn);
1035 		return;
1036 	}
1037 
1038 	pr_debug("Did not receive response to NOPIN on CID: %hu on"
1039 		" SID: %u, failing connection.\n", conn->cid,
1040 			conn->sess->sid);
1041 	conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1042 	spin_unlock_bh(&conn->nopin_timer_lock);
1043 
1044 	{
1045 	struct iscsi_portal_group *tpg = conn->sess->tpg;
1046 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
1047 
1048 	if (tiqn) {
1049 		spin_lock_bh(&tiqn->sess_err_stats.lock);
1050 		strcpy(tiqn->sess_err_stats.last_sess_fail_rem_name,
1051 				(void *)conn->sess->sess_ops->InitiatorName);
1052 		tiqn->sess_err_stats.last_sess_failure_type =
1053 				ISCSI_SESS_ERR_CXN_TIMEOUT;
1054 		tiqn->sess_err_stats.cxn_timeout_errors++;
1055 		conn->sess->conn_timeout_errors++;
1056 		spin_unlock_bh(&tiqn->sess_err_stats.lock);
1057 	}
1058 	}
1059 
1060 	iscsit_cause_connection_reinstatement(conn, 0);
1061 	iscsit_dec_conn_usage_count(conn);
1062 }
1063 
1064 void iscsit_mod_nopin_response_timer(struct iscsi_conn *conn)
1065 {
1066 	struct iscsi_session *sess = conn->sess;
1067 	struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1068 
1069 	spin_lock_bh(&conn->nopin_timer_lock);
1070 	if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1071 		spin_unlock_bh(&conn->nopin_timer_lock);
1072 		return;
1073 	}
1074 
1075 	mod_timer(&conn->nopin_response_timer,
1076 		(get_jiffies_64() + na->nopin_response_timeout * HZ));
1077 	spin_unlock_bh(&conn->nopin_timer_lock);
1078 }
1079 
1080 /*
1081  *	Called with conn->nopin_timer_lock held.
1082  */
1083 void iscsit_start_nopin_response_timer(struct iscsi_conn *conn)
1084 {
1085 	struct iscsi_session *sess = conn->sess;
1086 	struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1087 
1088 	spin_lock_bh(&conn->nopin_timer_lock);
1089 	if (conn->nopin_response_timer_flags & ISCSI_TF_RUNNING) {
1090 		spin_unlock_bh(&conn->nopin_timer_lock);
1091 		return;
1092 	}
1093 
1094 	init_timer(&conn->nopin_response_timer);
1095 	conn->nopin_response_timer.expires =
1096 		(get_jiffies_64() + na->nopin_response_timeout * HZ);
1097 	conn->nopin_response_timer.data = (unsigned long)conn;
1098 	conn->nopin_response_timer.function = iscsit_handle_nopin_response_timeout;
1099 	conn->nopin_response_timer_flags &= ~ISCSI_TF_STOP;
1100 	conn->nopin_response_timer_flags |= ISCSI_TF_RUNNING;
1101 	add_timer(&conn->nopin_response_timer);
1102 
1103 	pr_debug("Started NOPIN Response Timer on CID: %d to %u"
1104 		" seconds\n", conn->cid, na->nopin_response_timeout);
1105 	spin_unlock_bh(&conn->nopin_timer_lock);
1106 }
1107 
1108 void iscsit_stop_nopin_response_timer(struct iscsi_conn *conn)
1109 {
1110 	spin_lock_bh(&conn->nopin_timer_lock);
1111 	if (!(conn->nopin_response_timer_flags & ISCSI_TF_RUNNING)) {
1112 		spin_unlock_bh(&conn->nopin_timer_lock);
1113 		return;
1114 	}
1115 	conn->nopin_response_timer_flags |= ISCSI_TF_STOP;
1116 	spin_unlock_bh(&conn->nopin_timer_lock);
1117 
1118 	del_timer_sync(&conn->nopin_response_timer);
1119 
1120 	spin_lock_bh(&conn->nopin_timer_lock);
1121 	conn->nopin_response_timer_flags &= ~ISCSI_TF_RUNNING;
1122 	spin_unlock_bh(&conn->nopin_timer_lock);
1123 }
1124 
1125 static void iscsit_handle_nopin_timeout(unsigned long data)
1126 {
1127 	struct iscsi_conn *conn = (struct iscsi_conn *) data;
1128 
1129 	iscsit_inc_conn_usage_count(conn);
1130 
1131 	spin_lock_bh(&conn->nopin_timer_lock);
1132 	if (conn->nopin_timer_flags & ISCSI_TF_STOP) {
1133 		spin_unlock_bh(&conn->nopin_timer_lock);
1134 		iscsit_dec_conn_usage_count(conn);
1135 		return;
1136 	}
1137 	conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1138 	spin_unlock_bh(&conn->nopin_timer_lock);
1139 
1140 	iscsit_add_nopin(conn, 1);
1141 	iscsit_dec_conn_usage_count(conn);
1142 }
1143 
1144 /*
1145  * Called with conn->nopin_timer_lock held.
1146  */
1147 void __iscsit_start_nopin_timer(struct iscsi_conn *conn)
1148 {
1149 	struct iscsi_session *sess = conn->sess;
1150 	struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1151 	/*
1152 	* NOPIN timeout is disabled.
1153 	 */
1154 	if (!na->nopin_timeout)
1155 		return;
1156 
1157 	if (conn->nopin_timer_flags & ISCSI_TF_RUNNING)
1158 		return;
1159 
1160 	init_timer(&conn->nopin_timer);
1161 	conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1162 	conn->nopin_timer.data = (unsigned long)conn;
1163 	conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1164 	conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1165 	conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1166 	add_timer(&conn->nopin_timer);
1167 
1168 	pr_debug("Started NOPIN Timer on CID: %d at %u second"
1169 		" interval\n", conn->cid, na->nopin_timeout);
1170 }
1171 
1172 void iscsit_start_nopin_timer(struct iscsi_conn *conn)
1173 {
1174 	struct iscsi_session *sess = conn->sess;
1175 	struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
1176 	/*
1177 	 * NOPIN timeout is disabled..
1178 	 */
1179 	if (!na->nopin_timeout)
1180 		return;
1181 
1182 	spin_lock_bh(&conn->nopin_timer_lock);
1183 	if (conn->nopin_timer_flags & ISCSI_TF_RUNNING) {
1184 		spin_unlock_bh(&conn->nopin_timer_lock);
1185 		return;
1186 	}
1187 
1188 	init_timer(&conn->nopin_timer);
1189 	conn->nopin_timer.expires = (get_jiffies_64() + na->nopin_timeout * HZ);
1190 	conn->nopin_timer.data = (unsigned long)conn;
1191 	conn->nopin_timer.function = iscsit_handle_nopin_timeout;
1192 	conn->nopin_timer_flags &= ~ISCSI_TF_STOP;
1193 	conn->nopin_timer_flags |= ISCSI_TF_RUNNING;
1194 	add_timer(&conn->nopin_timer);
1195 
1196 	pr_debug("Started NOPIN Timer on CID: %d at %u second"
1197 			" interval\n", conn->cid, na->nopin_timeout);
1198 	spin_unlock_bh(&conn->nopin_timer_lock);
1199 }
1200 
1201 void iscsit_stop_nopin_timer(struct iscsi_conn *conn)
1202 {
1203 	spin_lock_bh(&conn->nopin_timer_lock);
1204 	if (!(conn->nopin_timer_flags & ISCSI_TF_RUNNING)) {
1205 		spin_unlock_bh(&conn->nopin_timer_lock);
1206 		return;
1207 	}
1208 	conn->nopin_timer_flags |= ISCSI_TF_STOP;
1209 	spin_unlock_bh(&conn->nopin_timer_lock);
1210 
1211 	del_timer_sync(&conn->nopin_timer);
1212 
1213 	spin_lock_bh(&conn->nopin_timer_lock);
1214 	conn->nopin_timer_flags &= ~ISCSI_TF_RUNNING;
1215 	spin_unlock_bh(&conn->nopin_timer_lock);
1216 }
1217 
1218 int iscsit_send_tx_data(
1219 	struct iscsi_cmd *cmd,
1220 	struct iscsi_conn *conn,
1221 	int use_misc)
1222 {
1223 	int tx_sent, tx_size;
1224 	u32 iov_count;
1225 	struct kvec *iov;
1226 
1227 send_data:
1228 	tx_size = cmd->tx_size;
1229 
1230 	if (!use_misc) {
1231 		iov = &cmd->iov_data[0];
1232 		iov_count = cmd->iov_data_count;
1233 	} else {
1234 		iov = &cmd->iov_misc[0];
1235 		iov_count = cmd->iov_misc_count;
1236 	}
1237 
1238 	tx_sent = tx_data(conn, &iov[0], iov_count, tx_size);
1239 	if (tx_size != tx_sent) {
1240 		if (tx_sent == -EAGAIN) {
1241 			pr_err("tx_data() returned -EAGAIN\n");
1242 			goto send_data;
1243 		} else
1244 			return -1;
1245 	}
1246 	cmd->tx_size = 0;
1247 
1248 	return 0;
1249 }
1250 
1251 int iscsit_fe_sendpage_sg(
1252 	struct iscsi_cmd *cmd,
1253 	struct iscsi_conn *conn)
1254 {
1255 	struct scatterlist *sg = cmd->first_data_sg;
1256 	struct kvec iov;
1257 	u32 tx_hdr_size, data_len;
1258 	u32 offset = cmd->first_data_sg_off;
1259 	int tx_sent, iov_off;
1260 
1261 send_hdr:
1262 	tx_hdr_size = ISCSI_HDR_LEN;
1263 	if (conn->conn_ops->HeaderDigest)
1264 		tx_hdr_size += ISCSI_CRC_LEN;
1265 
1266 	iov.iov_base = cmd->pdu;
1267 	iov.iov_len = tx_hdr_size;
1268 
1269 	tx_sent = tx_data(conn, &iov, 1, tx_hdr_size);
1270 	if (tx_hdr_size != tx_sent) {
1271 		if (tx_sent == -EAGAIN) {
1272 			pr_err("tx_data() returned -EAGAIN\n");
1273 			goto send_hdr;
1274 		}
1275 		return -1;
1276 	}
1277 
1278 	data_len = cmd->tx_size - tx_hdr_size - cmd->padding;
1279 	/*
1280 	 * Set iov_off used by padding and data digest tx_data() calls below
1281 	 * in order to determine proper offset into cmd->iov_data[]
1282 	 */
1283 	if (conn->conn_ops->DataDigest) {
1284 		data_len -= ISCSI_CRC_LEN;
1285 		if (cmd->padding)
1286 			iov_off = (cmd->iov_data_count - 2);
1287 		else
1288 			iov_off = (cmd->iov_data_count - 1);
1289 	} else {
1290 		iov_off = (cmd->iov_data_count - 1);
1291 	}
1292 	/*
1293 	 * Perform sendpage() for each page in the scatterlist
1294 	 */
1295 	while (data_len) {
1296 		u32 space = (sg->length - offset);
1297 		u32 sub_len = min_t(u32, data_len, space);
1298 send_pg:
1299 		tx_sent = conn->sock->ops->sendpage(conn->sock,
1300 					sg_page(sg), sg->offset + offset, sub_len, 0);
1301 		if (tx_sent != sub_len) {
1302 			if (tx_sent == -EAGAIN) {
1303 				pr_err("tcp_sendpage() returned"
1304 						" -EAGAIN\n");
1305 				goto send_pg;
1306 			}
1307 
1308 			pr_err("tcp_sendpage() failure: %d\n",
1309 					tx_sent);
1310 			return -1;
1311 		}
1312 
1313 		data_len -= sub_len;
1314 		offset = 0;
1315 		sg = sg_next(sg);
1316 	}
1317 
1318 send_padding:
1319 	if (cmd->padding) {
1320 		struct kvec *iov_p = &cmd->iov_data[iov_off++];
1321 
1322 		tx_sent = tx_data(conn, iov_p, 1, cmd->padding);
1323 		if (cmd->padding != tx_sent) {
1324 			if (tx_sent == -EAGAIN) {
1325 				pr_err("tx_data() returned -EAGAIN\n");
1326 				goto send_padding;
1327 			}
1328 			return -1;
1329 		}
1330 	}
1331 
1332 send_datacrc:
1333 	if (conn->conn_ops->DataDigest) {
1334 		struct kvec *iov_d = &cmd->iov_data[iov_off];
1335 
1336 		tx_sent = tx_data(conn, iov_d, 1, ISCSI_CRC_LEN);
1337 		if (ISCSI_CRC_LEN != tx_sent) {
1338 			if (tx_sent == -EAGAIN) {
1339 				pr_err("tx_data() returned -EAGAIN\n");
1340 				goto send_datacrc;
1341 			}
1342 			return -1;
1343 		}
1344 	}
1345 
1346 	return 0;
1347 }
1348 
1349 /*
1350  *      This function is used for mainly sending a ISCSI_TARG_LOGIN_RSP PDU
1351  *      back to the Initiator when an expection condition occurs with the
1352  *      errors set in status_class and status_detail.
1353  *
1354  *      Parameters:     iSCSI Connection, Status Class, Status Detail.
1355  *      Returns:        0 on success, -1 on error.
1356  */
1357 int iscsit_tx_login_rsp(struct iscsi_conn *conn, u8 status_class, u8 status_detail)
1358 {
1359 	u8 iscsi_hdr[ISCSI_HDR_LEN];
1360 	int err;
1361 	struct kvec iov;
1362 	struct iscsi_login_rsp *hdr;
1363 
1364 	iscsit_collect_login_stats(conn, status_class, status_detail);
1365 
1366 	memset(&iov, 0, sizeof(struct kvec));
1367 	memset(&iscsi_hdr, 0x0, ISCSI_HDR_LEN);
1368 
1369 	hdr	= (struct iscsi_login_rsp *)&iscsi_hdr;
1370 	hdr->opcode		= ISCSI_OP_LOGIN_RSP;
1371 	hdr->status_class	= status_class;
1372 	hdr->status_detail	= status_detail;
1373 	hdr->itt		= cpu_to_be32(conn->login_itt);
1374 
1375 	iov.iov_base		= &iscsi_hdr;
1376 	iov.iov_len		= ISCSI_HDR_LEN;
1377 
1378 	PRINT_BUFF(iscsi_hdr, ISCSI_HDR_LEN);
1379 
1380 	err = tx_data(conn, &iov, 1, ISCSI_HDR_LEN);
1381 	if (err != ISCSI_HDR_LEN) {
1382 		pr_err("tx_data returned less than expected\n");
1383 		return -1;
1384 	}
1385 
1386 	return 0;
1387 }
1388 
1389 void iscsit_print_session_params(struct iscsi_session *sess)
1390 {
1391 	struct iscsi_conn *conn;
1392 
1393 	pr_debug("-----------------------------[Session Params for"
1394 		" SID: %u]-----------------------------\n", sess->sid);
1395 	spin_lock_bh(&sess->conn_lock);
1396 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
1397 		iscsi_dump_conn_ops(conn->conn_ops);
1398 	spin_unlock_bh(&sess->conn_lock);
1399 
1400 	iscsi_dump_sess_ops(sess->sess_ops);
1401 }
1402 
1403 static int iscsit_do_rx_data(
1404 	struct iscsi_conn *conn,
1405 	struct iscsi_data_count *count)
1406 {
1407 	int data = count->data_length, rx_loop = 0, total_rx = 0, iov_len;
1408 	struct kvec *iov_p;
1409 	struct msghdr msg;
1410 
1411 	if (!conn || !conn->sock || !conn->conn_ops)
1412 		return -1;
1413 
1414 	memset(&msg, 0, sizeof(struct msghdr));
1415 
1416 	iov_p = count->iov;
1417 	iov_len	= count->iov_count;
1418 
1419 	while (total_rx < data) {
1420 		rx_loop = kernel_recvmsg(conn->sock, &msg, iov_p, iov_len,
1421 					(data - total_rx), MSG_WAITALL);
1422 		if (rx_loop <= 0) {
1423 			pr_debug("rx_loop: %d total_rx: %d\n",
1424 				rx_loop, total_rx);
1425 			return rx_loop;
1426 		}
1427 		total_rx += rx_loop;
1428 		pr_debug("rx_loop: %d, total_rx: %d, data: %d\n",
1429 				rx_loop, total_rx, data);
1430 	}
1431 
1432 	return total_rx;
1433 }
1434 
1435 static int iscsit_do_tx_data(
1436 	struct iscsi_conn *conn,
1437 	struct iscsi_data_count *count)
1438 {
1439 	int data = count->data_length, total_tx = 0, tx_loop = 0, iov_len;
1440 	struct kvec *iov_p;
1441 	struct msghdr msg;
1442 
1443 	if (!conn || !conn->sock || !conn->conn_ops)
1444 		return -1;
1445 
1446 	if (data <= 0) {
1447 		pr_err("Data length is: %d\n", data);
1448 		return -1;
1449 	}
1450 
1451 	memset(&msg, 0, sizeof(struct msghdr));
1452 
1453 	iov_p = count->iov;
1454 	iov_len = count->iov_count;
1455 
1456 	while (total_tx < data) {
1457 		tx_loop = kernel_sendmsg(conn->sock, &msg, iov_p, iov_len,
1458 					(data - total_tx));
1459 		if (tx_loop <= 0) {
1460 			pr_debug("tx_loop: %d total_tx %d\n",
1461 				tx_loop, total_tx);
1462 			return tx_loop;
1463 		}
1464 		total_tx += tx_loop;
1465 		pr_debug("tx_loop: %d, total_tx: %d, data: %d\n",
1466 					tx_loop, total_tx, data);
1467 	}
1468 
1469 	return total_tx;
1470 }
1471 
1472 int rx_data(
1473 	struct iscsi_conn *conn,
1474 	struct kvec *iov,
1475 	int iov_count,
1476 	int data)
1477 {
1478 	struct iscsi_data_count c;
1479 
1480 	if (!conn || !conn->sock || !conn->conn_ops)
1481 		return -1;
1482 
1483 	memset(&c, 0, sizeof(struct iscsi_data_count));
1484 	c.iov = iov;
1485 	c.iov_count = iov_count;
1486 	c.data_length = data;
1487 	c.type = ISCSI_RX_DATA;
1488 
1489 	return iscsit_do_rx_data(conn, &c);
1490 }
1491 
1492 int tx_data(
1493 	struct iscsi_conn *conn,
1494 	struct kvec *iov,
1495 	int iov_count,
1496 	int data)
1497 {
1498 	struct iscsi_data_count c;
1499 
1500 	if (!conn || !conn->sock || !conn->conn_ops)
1501 		return -1;
1502 
1503 	memset(&c, 0, sizeof(struct iscsi_data_count));
1504 	c.iov = iov;
1505 	c.iov_count = iov_count;
1506 	c.data_length = data;
1507 	c.type = ISCSI_TX_DATA;
1508 
1509 	return iscsit_do_tx_data(conn, &c);
1510 }
1511 
1512 void iscsit_collect_login_stats(
1513 	struct iscsi_conn *conn,
1514 	u8 status_class,
1515 	u8 status_detail)
1516 {
1517 	struct iscsi_param *intrname = NULL;
1518 	struct iscsi_tiqn *tiqn;
1519 	struct iscsi_login_stats *ls;
1520 
1521 	tiqn = iscsit_snmp_get_tiqn(conn);
1522 	if (!tiqn)
1523 		return;
1524 
1525 	ls = &tiqn->login_stats;
1526 
1527 	spin_lock(&ls->lock);
1528 	if (!strcmp(conn->login_ip, ls->last_intr_fail_ip_addr) &&
1529 	    ((get_jiffies_64() - ls->last_fail_time) < 10)) {
1530 		/* We already have the failure info for this login */
1531 		spin_unlock(&ls->lock);
1532 		return;
1533 	}
1534 
1535 	if (status_class == ISCSI_STATUS_CLS_SUCCESS)
1536 		ls->accepts++;
1537 	else if (status_class == ISCSI_STATUS_CLS_REDIRECT) {
1538 		ls->redirects++;
1539 		ls->last_fail_type = ISCSI_LOGIN_FAIL_REDIRECT;
1540 	} else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1541 		 (status_detail == ISCSI_LOGIN_STATUS_AUTH_FAILED)) {
1542 		ls->authenticate_fails++;
1543 		ls->last_fail_type =  ISCSI_LOGIN_FAIL_AUTHENTICATE;
1544 	} else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR)  &&
1545 		 (status_detail == ISCSI_LOGIN_STATUS_TGT_FORBIDDEN)) {
1546 		ls->authorize_fails++;
1547 		ls->last_fail_type = ISCSI_LOGIN_FAIL_AUTHORIZE;
1548 	} else if ((status_class == ISCSI_STATUS_CLS_INITIATOR_ERR) &&
1549 		 (status_detail == ISCSI_LOGIN_STATUS_INIT_ERR)) {
1550 		ls->negotiate_fails++;
1551 		ls->last_fail_type = ISCSI_LOGIN_FAIL_NEGOTIATE;
1552 	} else {
1553 		ls->other_fails++;
1554 		ls->last_fail_type = ISCSI_LOGIN_FAIL_OTHER;
1555 	}
1556 
1557 	/* Save initiator name, ip address and time, if it is a failed login */
1558 	if (status_class != ISCSI_STATUS_CLS_SUCCESS) {
1559 		if (conn->param_list)
1560 			intrname = iscsi_find_param_from_key(INITIATORNAME,
1561 							     conn->param_list);
1562 		strcpy(ls->last_intr_fail_name,
1563 		       (intrname ? intrname->value : "Unknown"));
1564 
1565 		ls->last_intr_fail_ip_family = conn->sock->sk->sk_family;
1566 		snprintf(ls->last_intr_fail_ip_addr, IPV6_ADDRESS_SPACE,
1567 				"%s", conn->login_ip);
1568 		ls->last_fail_time = get_jiffies_64();
1569 	}
1570 
1571 	spin_unlock(&ls->lock);
1572 }
1573 
1574 struct iscsi_tiqn *iscsit_snmp_get_tiqn(struct iscsi_conn *conn)
1575 {
1576 	struct iscsi_portal_group *tpg;
1577 
1578 	if (!conn || !conn->sess)
1579 		return NULL;
1580 
1581 	tpg = conn->sess->tpg;
1582 	if (!tpg)
1583 		return NULL;
1584 
1585 	if (!tpg->tpg_tiqn)
1586 		return NULL;
1587 
1588 	return tpg->tpg_tiqn;
1589 }
1590