xref: /linux/drivers/target/iscsi/iscsi_target.c (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
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/string.h>
22 #include <linux/kthread.h>
23 #include <linux/crypto.h>
24 #include <linux/completion.h>
25 #include <linux/module.h>
26 #include <linux/idr.h>
27 #include <asm/unaligned.h>
28 #include <scsi/scsi_device.h>
29 #include <scsi/iscsi_proto.h>
30 #include <scsi/scsi_tcq.h>
31 #include <target/target_core_base.h>
32 #include <target/target_core_fabric.h>
33 #include <target/target_core_configfs.h>
34 
35 #include "iscsi_target_core.h"
36 #include "iscsi_target_parameters.h"
37 #include "iscsi_target_seq_pdu_list.h"
38 #include "iscsi_target_tq.h"
39 #include "iscsi_target_configfs.h"
40 #include "iscsi_target_datain_values.h"
41 #include "iscsi_target_erl0.h"
42 #include "iscsi_target_erl1.h"
43 #include "iscsi_target_erl2.h"
44 #include "iscsi_target_login.h"
45 #include "iscsi_target_tmr.h"
46 #include "iscsi_target_tpg.h"
47 #include "iscsi_target_util.h"
48 #include "iscsi_target.h"
49 #include "iscsi_target_device.h"
50 #include "iscsi_target_stat.h"
51 
52 static LIST_HEAD(g_tiqn_list);
53 static LIST_HEAD(g_np_list);
54 static DEFINE_SPINLOCK(tiqn_lock);
55 static DEFINE_SPINLOCK(np_lock);
56 
57 static struct idr tiqn_idr;
58 struct idr sess_idr;
59 struct mutex auth_id_lock;
60 spinlock_t sess_idr_lock;
61 
62 struct iscsit_global *iscsit_global;
63 
64 struct kmem_cache *lio_cmd_cache;
65 struct kmem_cache *lio_qr_cache;
66 struct kmem_cache *lio_dr_cache;
67 struct kmem_cache *lio_ooo_cache;
68 struct kmem_cache *lio_r2t_cache;
69 
70 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
71 			unsigned char *buf, u32);
72 static int iscsit_logout_post_handler(struct iscsi_cmd *, struct iscsi_conn *);
73 
74 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
75 {
76 	struct iscsi_tiqn *tiqn = NULL;
77 
78 	spin_lock(&tiqn_lock);
79 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
80 		if (!strcmp(tiqn->tiqn, buf)) {
81 
82 			spin_lock(&tiqn->tiqn_state_lock);
83 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
84 				tiqn->tiqn_access_count++;
85 				spin_unlock(&tiqn->tiqn_state_lock);
86 				spin_unlock(&tiqn_lock);
87 				return tiqn;
88 			}
89 			spin_unlock(&tiqn->tiqn_state_lock);
90 		}
91 	}
92 	spin_unlock(&tiqn_lock);
93 
94 	return NULL;
95 }
96 
97 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
98 {
99 	spin_lock(&tiqn->tiqn_state_lock);
100 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
101 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
102 		spin_unlock(&tiqn->tiqn_state_lock);
103 		return 0;
104 	}
105 	spin_unlock(&tiqn->tiqn_state_lock);
106 
107 	return -1;
108 }
109 
110 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
111 {
112 	spin_lock(&tiqn->tiqn_state_lock);
113 	tiqn->tiqn_access_count--;
114 	spin_unlock(&tiqn->tiqn_state_lock);
115 }
116 
117 /*
118  * Note that IQN formatting is expected to be done in userspace, and
119  * no explict IQN format checks are done here.
120  */
121 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
122 {
123 	struct iscsi_tiqn *tiqn = NULL;
124 	int ret;
125 
126 	if (strlen(buf) >= ISCSI_IQN_LEN) {
127 		pr_err("Target IQN exceeds %d bytes\n",
128 				ISCSI_IQN_LEN);
129 		return ERR_PTR(-EINVAL);
130 	}
131 
132 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
133 	if (!tiqn) {
134 		pr_err("Unable to allocate struct iscsi_tiqn\n");
135 		return ERR_PTR(-ENOMEM);
136 	}
137 
138 	sprintf(tiqn->tiqn, "%s", buf);
139 	INIT_LIST_HEAD(&tiqn->tiqn_list);
140 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
141 	spin_lock_init(&tiqn->tiqn_state_lock);
142 	spin_lock_init(&tiqn->tiqn_tpg_lock);
143 	spin_lock_init(&tiqn->sess_err_stats.lock);
144 	spin_lock_init(&tiqn->login_stats.lock);
145 	spin_lock_init(&tiqn->logout_stats.lock);
146 
147 	if (!idr_pre_get(&tiqn_idr, GFP_KERNEL)) {
148 		pr_err("idr_pre_get() for tiqn_idr failed\n");
149 		kfree(tiqn);
150 		return ERR_PTR(-ENOMEM);
151 	}
152 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
153 
154 	spin_lock(&tiqn_lock);
155 	ret = idr_get_new(&tiqn_idr, NULL, &tiqn->tiqn_index);
156 	if (ret < 0) {
157 		pr_err("idr_get_new() failed for tiqn->tiqn_index\n");
158 		spin_unlock(&tiqn_lock);
159 		kfree(tiqn);
160 		return ERR_PTR(ret);
161 	}
162 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
163 	spin_unlock(&tiqn_lock);
164 
165 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
166 
167 	return tiqn;
168 
169 }
170 
171 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
172 {
173 	/*
174 	 * Wait for accesses to said struct iscsi_tiqn to end.
175 	 */
176 	spin_lock(&tiqn->tiqn_state_lock);
177 	while (tiqn->tiqn_access_count != 0) {
178 		spin_unlock(&tiqn->tiqn_state_lock);
179 		msleep(10);
180 		spin_lock(&tiqn->tiqn_state_lock);
181 	}
182 	spin_unlock(&tiqn->tiqn_state_lock);
183 }
184 
185 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
186 {
187 	/*
188 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
189 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
190 	 * attempts to access this struct iscsi_tiqn will fail from both transport
191 	 * fabric and control code paths.
192 	 */
193 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
194 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
195 		return;
196 	}
197 
198 	iscsit_wait_for_tiqn(tiqn);
199 
200 	spin_lock(&tiqn_lock);
201 	list_del(&tiqn->tiqn_list);
202 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
203 	spin_unlock(&tiqn_lock);
204 
205 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
206 			tiqn->tiqn);
207 	kfree(tiqn);
208 }
209 
210 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
211 {
212 	int ret;
213 	/*
214 	 * Determine if the network portal is accepting storage traffic.
215 	 */
216 	spin_lock_bh(&np->np_thread_lock);
217 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
218 		spin_unlock_bh(&np->np_thread_lock);
219 		return -1;
220 	}
221 	if (np->np_login_tpg) {
222 		pr_err("np->np_login_tpg() is not NULL!\n");
223 		spin_unlock_bh(&np->np_thread_lock);
224 		return -1;
225 	}
226 	spin_unlock_bh(&np->np_thread_lock);
227 	/*
228 	 * Determine if the portal group is accepting storage traffic.
229 	 */
230 	spin_lock_bh(&tpg->tpg_state_lock);
231 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
232 		spin_unlock_bh(&tpg->tpg_state_lock);
233 		return -1;
234 	}
235 	spin_unlock_bh(&tpg->tpg_state_lock);
236 
237 	/*
238 	 * Here we serialize access across the TIQN+TPG Tuple.
239 	 */
240 	ret = mutex_lock_interruptible(&tpg->np_login_lock);
241 	if ((ret != 0) || signal_pending(current))
242 		return -1;
243 
244 	spin_lock_bh(&np->np_thread_lock);
245 	np->np_login_tpg = tpg;
246 	spin_unlock_bh(&np->np_thread_lock);
247 
248 	return 0;
249 }
250 
251 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
252 {
253 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
254 
255 	spin_lock_bh(&np->np_thread_lock);
256 	np->np_login_tpg = NULL;
257 	spin_unlock_bh(&np->np_thread_lock);
258 
259 	mutex_unlock(&tpg->np_login_lock);
260 
261 	if (tiqn)
262 		iscsit_put_tiqn_for_login(tiqn);
263 
264 	return 0;
265 }
266 
267 static struct iscsi_np *iscsit_get_np(
268 	struct __kernel_sockaddr_storage *sockaddr,
269 	int network_transport)
270 {
271 	struct sockaddr_in *sock_in, *sock_in_e;
272 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
273 	struct iscsi_np *np;
274 	int ip_match = 0;
275 	u16 port;
276 
277 	spin_lock_bh(&np_lock);
278 	list_for_each_entry(np, &g_np_list, np_list) {
279 		spin_lock(&np->np_thread_lock);
280 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
281 			spin_unlock(&np->np_thread_lock);
282 			continue;
283 		}
284 
285 		if (sockaddr->ss_family == AF_INET6) {
286 			sock_in6 = (struct sockaddr_in6 *)sockaddr;
287 			sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
288 
289 			if (!memcmp(&sock_in6->sin6_addr.in6_u,
290 				    &sock_in6_e->sin6_addr.in6_u,
291 				    sizeof(struct in6_addr)))
292 				ip_match = 1;
293 
294 			port = ntohs(sock_in6->sin6_port);
295 		} else {
296 			sock_in = (struct sockaddr_in *)sockaddr;
297 			sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
298 
299 			if (sock_in->sin_addr.s_addr ==
300 			    sock_in_e->sin_addr.s_addr)
301 				ip_match = 1;
302 
303 			port = ntohs(sock_in->sin_port);
304 		}
305 
306 		if ((ip_match == 1) && (np->np_port == port) &&
307 		    (np->np_network_transport == network_transport)) {
308 			/*
309 			 * Increment the np_exports reference count now to
310 			 * prevent iscsit_del_np() below from being called
311 			 * while iscsi_tpg_add_network_portal() is called.
312 			 */
313 			np->np_exports++;
314 			spin_unlock(&np->np_thread_lock);
315 			spin_unlock_bh(&np_lock);
316 			return np;
317 		}
318 		spin_unlock(&np->np_thread_lock);
319 	}
320 	spin_unlock_bh(&np_lock);
321 
322 	return NULL;
323 }
324 
325 struct iscsi_np *iscsit_add_np(
326 	struct __kernel_sockaddr_storage *sockaddr,
327 	char *ip_str,
328 	int network_transport)
329 {
330 	struct sockaddr_in *sock_in;
331 	struct sockaddr_in6 *sock_in6;
332 	struct iscsi_np *np;
333 	int ret;
334 	/*
335 	 * Locate the existing struct iscsi_np if already active..
336 	 */
337 	np = iscsit_get_np(sockaddr, network_transport);
338 	if (np)
339 		return np;
340 
341 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
342 	if (!np) {
343 		pr_err("Unable to allocate memory for struct iscsi_np\n");
344 		return ERR_PTR(-ENOMEM);
345 	}
346 
347 	np->np_flags |= NPF_IP_NETWORK;
348 	if (sockaddr->ss_family == AF_INET6) {
349 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
350 		snprintf(np->np_ip, IPV6_ADDRESS_SPACE, "%s", ip_str);
351 		np->np_port = ntohs(sock_in6->sin6_port);
352 	} else {
353 		sock_in = (struct sockaddr_in *)sockaddr;
354 		sprintf(np->np_ip, "%s", ip_str);
355 		np->np_port = ntohs(sock_in->sin_port);
356 	}
357 
358 	np->np_network_transport = network_transport;
359 	spin_lock_init(&np->np_thread_lock);
360 	init_completion(&np->np_restart_comp);
361 	INIT_LIST_HEAD(&np->np_list);
362 
363 	ret = iscsi_target_setup_login_socket(np, sockaddr);
364 	if (ret != 0) {
365 		kfree(np);
366 		return ERR_PTR(ret);
367 	}
368 
369 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
370 	if (IS_ERR(np->np_thread)) {
371 		pr_err("Unable to create kthread: iscsi_np\n");
372 		ret = PTR_ERR(np->np_thread);
373 		kfree(np);
374 		return ERR_PTR(ret);
375 	}
376 	/*
377 	 * Increment the np_exports reference count now to prevent
378 	 * iscsit_del_np() below from being run while a new call to
379 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
380 	 * active.  We don't need to hold np->np_thread_lock at this
381 	 * point because iscsi_np has not been added to g_np_list yet.
382 	 */
383 	np->np_exports = 1;
384 
385 	spin_lock_bh(&np_lock);
386 	list_add_tail(&np->np_list, &g_np_list);
387 	spin_unlock_bh(&np_lock);
388 
389 	pr_debug("CORE[0] - Added Network Portal: %s:%hu on %s\n",
390 		np->np_ip, np->np_port, (np->np_network_transport == ISCSI_TCP) ?
391 		"TCP" : "SCTP");
392 
393 	return np;
394 }
395 
396 int iscsit_reset_np_thread(
397 	struct iscsi_np *np,
398 	struct iscsi_tpg_np *tpg_np,
399 	struct iscsi_portal_group *tpg)
400 {
401 	spin_lock_bh(&np->np_thread_lock);
402 	if (tpg && tpg_np) {
403 		/*
404 		 * The reset operation need only be performed when the
405 		 * passed struct iscsi_portal_group has a login in progress
406 		 * to one of the network portals.
407 		 */
408 		if (tpg_np->tpg_np->np_login_tpg != tpg) {
409 			spin_unlock_bh(&np->np_thread_lock);
410 			return 0;
411 		}
412 	}
413 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
414 		spin_unlock_bh(&np->np_thread_lock);
415 		return 0;
416 	}
417 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
418 
419 	if (np->np_thread) {
420 		spin_unlock_bh(&np->np_thread_lock);
421 		send_sig(SIGINT, np->np_thread, 1);
422 		wait_for_completion(&np->np_restart_comp);
423 		spin_lock_bh(&np->np_thread_lock);
424 	}
425 	spin_unlock_bh(&np->np_thread_lock);
426 
427 	return 0;
428 }
429 
430 int iscsit_del_np_comm(struct iscsi_np *np)
431 {
432 	if (np->np_socket)
433 		sock_release(np->np_socket);
434 	return 0;
435 }
436 
437 int iscsit_del_np(struct iscsi_np *np)
438 {
439 	spin_lock_bh(&np->np_thread_lock);
440 	np->np_exports--;
441 	if (np->np_exports) {
442 		spin_unlock_bh(&np->np_thread_lock);
443 		return 0;
444 	}
445 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
446 	spin_unlock_bh(&np->np_thread_lock);
447 
448 	if (np->np_thread) {
449 		/*
450 		 * We need to send the signal to wakeup Linux/Net
451 		 * which may be sleeping in sock_accept()..
452 		 */
453 		send_sig(SIGINT, np->np_thread, 1);
454 		kthread_stop(np->np_thread);
455 	}
456 	iscsit_del_np_comm(np);
457 
458 	spin_lock_bh(&np_lock);
459 	list_del(&np->np_list);
460 	spin_unlock_bh(&np_lock);
461 
462 	pr_debug("CORE[0] - Removed Network Portal: %s:%hu on %s\n",
463 		np->np_ip, np->np_port, (np->np_network_transport == ISCSI_TCP) ?
464 		"TCP" : "SCTP");
465 
466 	kfree(np);
467 	return 0;
468 }
469 
470 static int __init iscsi_target_init_module(void)
471 {
472 	int ret = 0;
473 
474 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
475 
476 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
477 	if (!iscsit_global) {
478 		pr_err("Unable to allocate memory for iscsit_global\n");
479 		return -1;
480 	}
481 	mutex_init(&auth_id_lock);
482 	spin_lock_init(&sess_idr_lock);
483 	idr_init(&tiqn_idr);
484 	idr_init(&sess_idr);
485 
486 	ret = iscsi_target_register_configfs();
487 	if (ret < 0)
488 		goto out;
489 
490 	ret = iscsi_thread_set_init();
491 	if (ret < 0)
492 		goto configfs_out;
493 
494 	if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
495 			TARGET_THREAD_SET_COUNT) {
496 		pr_err("iscsi_allocate_thread_sets() returned"
497 			" unexpected value!\n");
498 		goto ts_out1;
499 	}
500 
501 	lio_cmd_cache = kmem_cache_create("lio_cmd_cache",
502 			sizeof(struct iscsi_cmd), __alignof__(struct iscsi_cmd),
503 			0, NULL);
504 	if (!lio_cmd_cache) {
505 		pr_err("Unable to kmem_cache_create() for"
506 				" lio_cmd_cache\n");
507 		goto ts_out2;
508 	}
509 
510 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
511 			sizeof(struct iscsi_queue_req),
512 			__alignof__(struct iscsi_queue_req), 0, NULL);
513 	if (!lio_qr_cache) {
514 		pr_err("nable to kmem_cache_create() for"
515 				" lio_qr_cache\n");
516 		goto cmd_out;
517 	}
518 
519 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
520 			sizeof(struct iscsi_datain_req),
521 			__alignof__(struct iscsi_datain_req), 0, NULL);
522 	if (!lio_dr_cache) {
523 		pr_err("Unable to kmem_cache_create() for"
524 				" lio_dr_cache\n");
525 		goto qr_out;
526 	}
527 
528 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
529 			sizeof(struct iscsi_ooo_cmdsn),
530 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
531 	if (!lio_ooo_cache) {
532 		pr_err("Unable to kmem_cache_create() for"
533 				" lio_ooo_cache\n");
534 		goto dr_out;
535 	}
536 
537 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
538 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
539 			0, NULL);
540 	if (!lio_r2t_cache) {
541 		pr_err("Unable to kmem_cache_create() for"
542 				" lio_r2t_cache\n");
543 		goto ooo_out;
544 	}
545 
546 	if (iscsit_load_discovery_tpg() < 0)
547 		goto r2t_out;
548 
549 	return ret;
550 r2t_out:
551 	kmem_cache_destroy(lio_r2t_cache);
552 ooo_out:
553 	kmem_cache_destroy(lio_ooo_cache);
554 dr_out:
555 	kmem_cache_destroy(lio_dr_cache);
556 qr_out:
557 	kmem_cache_destroy(lio_qr_cache);
558 cmd_out:
559 	kmem_cache_destroy(lio_cmd_cache);
560 ts_out2:
561 	iscsi_deallocate_thread_sets();
562 ts_out1:
563 	iscsi_thread_set_free();
564 configfs_out:
565 	iscsi_target_deregister_configfs();
566 out:
567 	kfree(iscsit_global);
568 	return -ENOMEM;
569 }
570 
571 static void __exit iscsi_target_cleanup_module(void)
572 {
573 	iscsi_deallocate_thread_sets();
574 	iscsi_thread_set_free();
575 	iscsit_release_discovery_tpg();
576 	kmem_cache_destroy(lio_cmd_cache);
577 	kmem_cache_destroy(lio_qr_cache);
578 	kmem_cache_destroy(lio_dr_cache);
579 	kmem_cache_destroy(lio_ooo_cache);
580 	kmem_cache_destroy(lio_r2t_cache);
581 
582 	iscsi_target_deregister_configfs();
583 
584 	kfree(iscsit_global);
585 }
586 
587 static int iscsit_add_reject(
588 	u8 reason,
589 	int fail_conn,
590 	unsigned char *buf,
591 	struct iscsi_conn *conn)
592 {
593 	struct iscsi_cmd *cmd;
594 	struct iscsi_reject *hdr;
595 	int ret;
596 
597 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
598 	if (!cmd)
599 		return -1;
600 
601 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
602 	if (fail_conn)
603 		cmd->cmd_flags |= ICF_REJECT_FAIL_CONN;
604 
605 	hdr	= (struct iscsi_reject *) cmd->pdu;
606 	hdr->reason = reason;
607 
608 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
609 	if (!cmd->buf_ptr) {
610 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
611 		iscsit_release_cmd(cmd);
612 		return -1;
613 	}
614 
615 	spin_lock_bh(&conn->cmd_lock);
616 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
617 	spin_unlock_bh(&conn->cmd_lock);
618 
619 	cmd->i_state = ISTATE_SEND_REJECT;
620 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
621 
622 	ret = wait_for_completion_interruptible(&cmd->reject_comp);
623 	if (ret != 0)
624 		return -1;
625 
626 	return (!fail_conn) ? 0 : -1;
627 }
628 
629 int iscsit_add_reject_from_cmd(
630 	u8 reason,
631 	int fail_conn,
632 	int add_to_conn,
633 	unsigned char *buf,
634 	struct iscsi_cmd *cmd)
635 {
636 	struct iscsi_conn *conn;
637 	struct iscsi_reject *hdr;
638 	int ret;
639 
640 	if (!cmd->conn) {
641 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
642 				cmd->init_task_tag);
643 		return -1;
644 	}
645 	conn = cmd->conn;
646 
647 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
648 	if (fail_conn)
649 		cmd->cmd_flags |= ICF_REJECT_FAIL_CONN;
650 
651 	hdr	= (struct iscsi_reject *) cmd->pdu;
652 	hdr->reason = reason;
653 
654 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
655 	if (!cmd->buf_ptr) {
656 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
657 		iscsit_release_cmd(cmd);
658 		return -1;
659 	}
660 
661 	if (add_to_conn) {
662 		spin_lock_bh(&conn->cmd_lock);
663 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
664 		spin_unlock_bh(&conn->cmd_lock);
665 	}
666 
667 	cmd->i_state = ISTATE_SEND_REJECT;
668 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
669 
670 	ret = wait_for_completion_interruptible(&cmd->reject_comp);
671 	if (ret != 0)
672 		return -1;
673 
674 	return (!fail_conn) ? 0 : -1;
675 }
676 
677 /*
678  * Map some portion of the allocated scatterlist to an iovec, suitable for
679  * kernel sockets to copy data in/out.
680  */
681 static int iscsit_map_iovec(
682 	struct iscsi_cmd *cmd,
683 	struct kvec *iov,
684 	u32 data_offset,
685 	u32 data_length)
686 {
687 	u32 i = 0;
688 	struct scatterlist *sg;
689 	unsigned int page_off;
690 
691 	/*
692 	 * We know each entry in t_data_sg contains a page.
693 	 */
694 	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
695 	page_off = (data_offset % PAGE_SIZE);
696 
697 	cmd->first_data_sg = sg;
698 	cmd->first_data_sg_off = page_off;
699 
700 	while (data_length) {
701 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
702 
703 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
704 		iov[i].iov_len = cur_len;
705 
706 		data_length -= cur_len;
707 		page_off = 0;
708 		sg = sg_next(sg);
709 		i++;
710 	}
711 
712 	cmd->kmapped_nents = i;
713 
714 	return i;
715 }
716 
717 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
718 {
719 	u32 i;
720 	struct scatterlist *sg;
721 
722 	sg = cmd->first_data_sg;
723 
724 	for (i = 0; i < cmd->kmapped_nents; i++)
725 		kunmap(sg_page(&sg[i]));
726 }
727 
728 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
729 {
730 	struct iscsi_cmd *cmd;
731 
732 	conn->exp_statsn = exp_statsn;
733 
734 	spin_lock_bh(&conn->cmd_lock);
735 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
736 		spin_lock(&cmd->istate_lock);
737 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
738 		    (cmd->stat_sn < exp_statsn)) {
739 			cmd->i_state = ISTATE_REMOVE;
740 			spin_unlock(&cmd->istate_lock);
741 			iscsit_add_cmd_to_immediate_queue(cmd, conn,
742 						cmd->i_state);
743 			continue;
744 		}
745 		spin_unlock(&cmd->istate_lock);
746 	}
747 	spin_unlock_bh(&conn->cmd_lock);
748 }
749 
750 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
751 {
752 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
753 
754 	iov_count += ISCSI_IOV_DATA_BUFFER;
755 
756 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
757 	if (!cmd->iov_data) {
758 		pr_err("Unable to allocate cmd->iov_data\n");
759 		return -ENOMEM;
760 	}
761 
762 	cmd->orig_iov_data_count = iov_count;
763 	return 0;
764 }
765 
766 static int iscsit_handle_scsi_cmd(
767 	struct iscsi_conn *conn,
768 	unsigned char *buf)
769 {
770 	int	data_direction, cmdsn_ret = 0, immed_ret, ret, transport_ret;
771 	int	dump_immediate_data = 0, send_check_condition = 0, payload_length;
772 	struct iscsi_cmd	*cmd = NULL;
773 	struct iscsi_scsi_req *hdr;
774 	int iscsi_task_attr;
775 	int sam_task_attr;
776 
777 	spin_lock_bh(&conn->sess->session_stats_lock);
778 	conn->sess->cmd_pdus++;
779 	if (conn->sess->se_sess->se_node_acl) {
780 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
781 		conn->sess->se_sess->se_node_acl->num_cmds++;
782 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
783 	}
784 	spin_unlock_bh(&conn->sess->session_stats_lock);
785 
786 	hdr			= (struct iscsi_scsi_req *) buf;
787 	payload_length		= ntoh24(hdr->dlength);
788 	hdr->itt		= be32_to_cpu(hdr->itt);
789 	hdr->data_length	= be32_to_cpu(hdr->data_length);
790 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
791 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
792 
793 	/* FIXME; Add checks for AdditionalHeaderSegment */
794 
795 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
796 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
797 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
798 				" not set. Bad iSCSI Initiator.\n");
799 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
800 				buf, conn);
801 	}
802 
803 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
804 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
805 		/*
806 		 * Vmware ESX v3.0 uses a modified Cisco Initiator (v3.4.2)
807 		 * that adds support for RESERVE/RELEASE.  There is a bug
808 		 * add with this new functionality that sets R/W bits when
809 		 * neither CDB carries any READ or WRITE datapayloads.
810 		 */
811 		if ((hdr->cdb[0] == 0x16) || (hdr->cdb[0] == 0x17)) {
812 			hdr->flags &= ~ISCSI_FLAG_CMD_READ;
813 			hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
814 			goto done;
815 		}
816 
817 		pr_err("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
818 			" set when Expected Data Transfer Length is 0 for"
819 			" CDB: 0x%02x. Bad iSCSI Initiator.\n", hdr->cdb[0]);
820 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
821 				buf, conn);
822 	}
823 done:
824 
825 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
826 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
827 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
828 			" MUST be set if Expected Data Transfer Length is not 0."
829 			" Bad iSCSI Initiator\n");
830 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
831 				buf, conn);
832 	}
833 
834 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
835 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
836 		pr_err("Bidirectional operations not supported!\n");
837 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
838 				buf, conn);
839 	}
840 
841 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
842 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
843 				" Scsi Command PDU.\n");
844 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
845 				buf, conn);
846 	}
847 
848 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
849 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
850 			" protocol error.\n", payload_length);
851 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
852 				buf, conn);
853 	}
854 
855 	if ((hdr->data_length == payload_length) &&
856 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
857 		pr_err("Expected Data Transfer Length and Length of"
858 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
859 			" bit is not set protocol error\n");
860 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
861 				buf, conn);
862 	}
863 
864 	if (payload_length > hdr->data_length) {
865 		pr_err("DataSegmentLength: %u is greater than"
866 			" EDTL: %u, protocol error.\n", payload_length,
867 				hdr->data_length);
868 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
869 				buf, conn);
870 	}
871 
872 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
873 		pr_err("DataSegmentLength: %u is greater than"
874 			" MaxRecvDataSegmentLength: %u, protocol error.\n",
875 			payload_length, conn->conn_ops->MaxRecvDataSegmentLength);
876 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
877 				buf, conn);
878 	}
879 
880 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
881 		pr_err("DataSegmentLength: %u is greater than"
882 			" FirstBurstLength: %u, protocol error.\n",
883 			payload_length, conn->sess->sess_ops->FirstBurstLength);
884 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
885 					buf, conn);
886 	}
887 
888 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
889 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
890 			  DMA_NONE;
891 
892 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
893 	if (!cmd)
894 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES, 1,
895 					 buf, conn);
896 
897 	cmd->data_direction = data_direction;
898 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
899 	/*
900 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
901 	 */
902 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
903 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
904 		sam_task_attr = MSG_SIMPLE_TAG;
905 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
906 		sam_task_attr = MSG_ORDERED_TAG;
907 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
908 		sam_task_attr = MSG_HEAD_TAG;
909 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
910 		sam_task_attr = MSG_ACA_TAG;
911 	else {
912 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
913 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
914 		sam_task_attr = MSG_SIMPLE_TAG;
915 	}
916 
917 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
918 	cmd->i_state		= ISTATE_NEW_CMD;
919 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
920 	cmd->immediate_data	= (payload_length) ? 1 : 0;
921 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
922 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
923 	if (cmd->unsolicited_data)
924 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
925 
926 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
927 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
928 		spin_lock_bh(&conn->sess->ttt_lock);
929 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
930 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
931 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
932 		spin_unlock_bh(&conn->sess->ttt_lock);
933 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
934 		cmd->targ_xfer_tag = 0xFFFFFFFF;
935 	cmd->cmd_sn		= hdr->cmdsn;
936 	cmd->exp_stat_sn	= hdr->exp_statsn;
937 	cmd->first_burst_len	= payload_length;
938 
939 	if (cmd->data_direction == DMA_FROM_DEVICE) {
940 		struct iscsi_datain_req *dr;
941 
942 		dr = iscsit_allocate_datain_req();
943 		if (!dr)
944 			return iscsit_add_reject_from_cmd(
945 					ISCSI_REASON_BOOKMARK_NO_RESOURCES,
946 					1, 1, buf, cmd);
947 
948 		iscsit_attach_datain_req(cmd, dr);
949 	}
950 
951 	/*
952 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
953 	 */
954 	transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
955 			conn->sess->se_sess, hdr->data_length, cmd->data_direction,
956 			sam_task_attr, &cmd->sense_buffer[0]);
957 
958 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
959 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
960 		hdr->cmdsn, hdr->data_length, payload_length, conn->cid);
961 
962 	/*
963 	 * The CDB is going to an se_device_t.
964 	 */
965 	ret = transport_lookup_cmd_lun(&cmd->se_cmd,
966 				       scsilun_to_int(&hdr->lun));
967 	if (ret < 0) {
968 		if (cmd->se_cmd.scsi_sense_reason == TCM_NON_EXISTENT_LUN) {
969 			pr_debug("Responding to non-acl'ed,"
970 				" non-existent or non-exported iSCSI LUN:"
971 				" 0x%016Lx\n", get_unaligned_le64(&hdr->lun));
972 		}
973 		send_check_condition = 1;
974 		goto attach_cmd;
975 	}
976 
977 	transport_ret = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
978 	if (transport_ret == -ENOMEM) {
979 		return iscsit_add_reject_from_cmd(
980 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
981 				1, 1, buf, cmd);
982 	} else if (transport_ret < 0) {
983 		/*
984 		 * Unsupported SAM Opcode.  CHECK_CONDITION will be sent
985 		 * in iscsit_execute_cmd() during the CmdSN OOO Execution
986 		 * Mechinism.
987 		 */
988 		send_check_condition = 1;
989 	} else {
990 		if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0)
991 			return iscsit_add_reject_from_cmd(
992 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
993 				1, 1, buf, cmd);
994 	}
995 
996 attach_cmd:
997 	spin_lock_bh(&conn->cmd_lock);
998 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
999 	spin_unlock_bh(&conn->cmd_lock);
1000 	/*
1001 	 * Check if we need to delay processing because of ALUA
1002 	 * Active/NonOptimized primary access state..
1003 	 */
1004 	core_alua_check_nonop_delay(&cmd->se_cmd);
1005 
1006 	ret = iscsit_allocate_iovecs(cmd);
1007 	if (ret < 0)
1008 		return iscsit_add_reject_from_cmd(
1009 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1010 				1, 0, buf, cmd);
1011 	/*
1012 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1013 	 * the Immediate Bit is not set, and no Immediate
1014 	 * Data is attached.
1015 	 *
1016 	 * A PDU/CmdSN carrying Immediate Data can only
1017 	 * be processed after the DataCRC has passed.
1018 	 * If the DataCRC fails, the CmdSN MUST NOT
1019 	 * be acknowledged. (See below)
1020 	 */
1021 	if (!cmd->immediate_data) {
1022 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1023 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1024 			return 0;
1025 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1026 			return iscsit_add_reject_from_cmd(
1027 				ISCSI_REASON_PROTOCOL_ERROR,
1028 				1, 0, buf, cmd);
1029 	}
1030 
1031 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1032 
1033 	/*
1034 	 * If no Immediate Data is attached, it's OK to return now.
1035 	 */
1036 	if (!cmd->immediate_data) {
1037 		if (send_check_condition)
1038 			return 0;
1039 
1040 		if (cmd->unsolicited_data) {
1041 			iscsit_set_dataout_sequence_values(cmd);
1042 
1043 			spin_lock_bh(&cmd->dataout_timeout_lock);
1044 			iscsit_start_dataout_timer(cmd, cmd->conn);
1045 			spin_unlock_bh(&cmd->dataout_timeout_lock);
1046 		}
1047 
1048 		return 0;
1049 	}
1050 
1051 	/*
1052 	 * Early CHECK_CONDITIONs never make it to the transport processing
1053 	 * thread.  They are processed in CmdSN order by
1054 	 * iscsit_check_received_cmdsn() below.
1055 	 */
1056 	if (send_check_condition) {
1057 		immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1058 		dump_immediate_data = 1;
1059 		goto after_immediate_data;
1060 	}
1061 	/*
1062 	 * Call directly into transport_generic_new_cmd() to perform
1063 	 * the backend memory allocation.
1064 	 */
1065 	ret = transport_generic_new_cmd(&cmd->se_cmd);
1066 	if (ret < 0) {
1067 		immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1068 		dump_immediate_data = 1;
1069 		goto after_immediate_data;
1070 	}
1071 
1072 	immed_ret = iscsit_handle_immediate_data(cmd, buf, payload_length);
1073 after_immediate_data:
1074 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1075 		/*
1076 		 * A PDU/CmdSN carrying Immediate Data passed
1077 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1078 		 * Immediate Bit is not set.
1079 		 */
1080 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1081 		/*
1082 		 * Special case for Unsupported SAM WRITE Opcodes
1083 		 * and ImmediateData=Yes.
1084 		 */
1085 		if (dump_immediate_data) {
1086 			if (iscsit_dump_data_payload(conn, payload_length, 1) < 0)
1087 				return -1;
1088 		} else if (cmd->unsolicited_data) {
1089 			iscsit_set_dataout_sequence_values(cmd);
1090 
1091 			spin_lock_bh(&cmd->dataout_timeout_lock);
1092 			iscsit_start_dataout_timer(cmd, cmd->conn);
1093 			spin_unlock_bh(&cmd->dataout_timeout_lock);
1094 		}
1095 
1096 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1097 			return iscsit_add_reject_from_cmd(
1098 				ISCSI_REASON_PROTOCOL_ERROR,
1099 				1, 0, buf, cmd);
1100 
1101 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1102 		/*
1103 		 * Immediate Data failed DataCRC and ERL>=1,
1104 		 * silently drop this PDU and let the initiator
1105 		 * plug the CmdSN gap.
1106 		 *
1107 		 * FIXME: Send Unsolicited NOPIN with reserved
1108 		 * TTT here to help the initiator figure out
1109 		 * the missing CmdSN, although they should be
1110 		 * intelligent enough to determine the missing
1111 		 * CmdSN and issue a retry to plug the sequence.
1112 		 */
1113 		cmd->i_state = ISTATE_REMOVE;
1114 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
1115 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1116 		return -1;
1117 
1118 	return 0;
1119 }
1120 
1121 static u32 iscsit_do_crypto_hash_sg(
1122 	struct hash_desc *hash,
1123 	struct iscsi_cmd *cmd,
1124 	u32 data_offset,
1125 	u32 data_length,
1126 	u32 padding,
1127 	u8 *pad_bytes)
1128 {
1129 	u32 data_crc;
1130 	u32 i;
1131 	struct scatterlist *sg;
1132 	unsigned int page_off;
1133 
1134 	crypto_hash_init(hash);
1135 
1136 	sg = cmd->first_data_sg;
1137 	page_off = cmd->first_data_sg_off;
1138 
1139 	i = 0;
1140 	while (data_length) {
1141 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1142 
1143 		crypto_hash_update(hash, &sg[i], cur_len);
1144 
1145 		data_length -= cur_len;
1146 		page_off = 0;
1147 		i++;
1148 	}
1149 
1150 	if (padding) {
1151 		struct scatterlist pad_sg;
1152 
1153 		sg_init_one(&pad_sg, pad_bytes, padding);
1154 		crypto_hash_update(hash, &pad_sg, padding);
1155 	}
1156 	crypto_hash_final(hash, (u8 *) &data_crc);
1157 
1158 	return data_crc;
1159 }
1160 
1161 static void iscsit_do_crypto_hash_buf(
1162 	struct hash_desc *hash,
1163 	unsigned char *buf,
1164 	u32 payload_length,
1165 	u32 padding,
1166 	u8 *pad_bytes,
1167 	u8 *data_crc)
1168 {
1169 	struct scatterlist sg;
1170 
1171 	crypto_hash_init(hash);
1172 
1173 	sg_init_one(&sg, buf, payload_length);
1174 	crypto_hash_update(hash, &sg, payload_length);
1175 
1176 	if (padding) {
1177 		sg_init_one(&sg, pad_bytes, padding);
1178 		crypto_hash_update(hash, &sg, padding);
1179 	}
1180 	crypto_hash_final(hash, data_crc);
1181 }
1182 
1183 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1184 {
1185 	int iov_ret, ooo_cmdsn = 0, ret;
1186 	u8 data_crc_failed = 0;
1187 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0;
1188 	u32 rx_size = 0, payload_length;
1189 	struct iscsi_cmd *cmd = NULL;
1190 	struct se_cmd *se_cmd;
1191 	struct iscsi_data *hdr;
1192 	struct kvec *iov;
1193 	unsigned long flags;
1194 
1195 	hdr			= (struct iscsi_data *) buf;
1196 	payload_length		= ntoh24(hdr->dlength);
1197 	hdr->itt		= be32_to_cpu(hdr->itt);
1198 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1199 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1200 	hdr->datasn		= be32_to_cpu(hdr->datasn);
1201 	hdr->offset		= be32_to_cpu(hdr->offset);
1202 
1203 	if (!payload_length) {
1204 		pr_err("DataOUT payload is ZERO, protocol error.\n");
1205 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1206 					buf, conn);
1207 	}
1208 
1209 	/* iSCSI write */
1210 	spin_lock_bh(&conn->sess->session_stats_lock);
1211 	conn->sess->rx_data_octets += payload_length;
1212 	if (conn->sess->se_sess->se_node_acl) {
1213 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
1214 		conn->sess->se_sess->se_node_acl->write_bytes += payload_length;
1215 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
1216 	}
1217 	spin_unlock_bh(&conn->sess->session_stats_lock);
1218 
1219 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1220 		pr_err("DataSegmentLength: %u is greater than"
1221 			" MaxRecvDataSegmentLength: %u\n", payload_length,
1222 			conn->conn_ops->MaxRecvDataSegmentLength);
1223 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1224 					buf, conn);
1225 	}
1226 
1227 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1228 			payload_length);
1229 	if (!cmd)
1230 		return 0;
1231 
1232 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1233 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1234 		hdr->itt, hdr->ttt, hdr->datasn, hdr->offset,
1235 		payload_length, conn->cid);
1236 
1237 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1238 		pr_err("Command ITT: 0x%08x received DataOUT after"
1239 			" last DataOUT received, dumping payload\n",
1240 			cmd->init_task_tag);
1241 		return iscsit_dump_data_payload(conn, payload_length, 1);
1242 	}
1243 
1244 	if (cmd->data_direction != DMA_TO_DEVICE) {
1245 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1246 			" NON-WRITE command.\n", cmd->init_task_tag);
1247 		return iscsit_add_reject_from_cmd(ISCSI_REASON_PROTOCOL_ERROR,
1248 				1, 0, buf, cmd);
1249 	}
1250 	se_cmd = &cmd->se_cmd;
1251 	iscsit_mod_dataout_timer(cmd);
1252 
1253 	if ((hdr->offset + payload_length) > cmd->se_cmd.data_length) {
1254 		pr_err("DataOut Offset: %u, Length %u greater than"
1255 			" iSCSI Command EDTL %u, protocol error.\n",
1256 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1257 		return iscsit_add_reject_from_cmd(ISCSI_REASON_BOOKMARK_INVALID,
1258 				1, 0, buf, cmd);
1259 	}
1260 
1261 	if (cmd->unsolicited_data) {
1262 		int dump_unsolicited_data = 0;
1263 
1264 		if (conn->sess->sess_ops->InitialR2T) {
1265 			pr_err("Received unexpected unsolicited data"
1266 				" while InitialR2T=Yes, protocol error.\n");
1267 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1268 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1269 			return -1;
1270 		}
1271 		/*
1272 		 * Special case for dealing with Unsolicited DataOUT
1273 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1274 		 * failures;
1275 		 */
1276 
1277 		/* Something's amiss if we're not in WRITE_PENDING state... */
1278 		spin_lock_irqsave(&se_cmd->t_state_lock, flags);
1279 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1280 		spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
1281 
1282 		spin_lock_irqsave(&se_cmd->t_state_lock, flags);
1283 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) ||
1284 		     (se_cmd->se_cmd_flags & SCF_SCSI_CDB_EXCEPTION))
1285 			dump_unsolicited_data = 1;
1286 		spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
1287 
1288 		if (dump_unsolicited_data) {
1289 			/*
1290 			 * Check if a delayed TASK_ABORTED status needs to
1291 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1292 			 * received with the unsolicitied data out.
1293 			 */
1294 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1295 				iscsit_stop_dataout_timer(cmd);
1296 
1297 			transport_check_aborted_status(se_cmd,
1298 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1299 			return iscsit_dump_data_payload(conn, payload_length, 1);
1300 		}
1301 	} else {
1302 		/*
1303 		 * For the normal solicited data path:
1304 		 *
1305 		 * Check for a delayed TASK_ABORTED status and dump any
1306 		 * incoming data out payload if one exists.  Also, when the
1307 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1308 		 * data out sequence, we decrement outstanding_r2ts.  Once
1309 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1310 		 * TASK_ABORTED status.
1311 		 */
1312 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1313 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1314 				if (--cmd->outstanding_r2ts < 1) {
1315 					iscsit_stop_dataout_timer(cmd);
1316 					transport_check_aborted_status(
1317 							se_cmd, 1);
1318 				}
1319 
1320 			return iscsit_dump_data_payload(conn, payload_length, 1);
1321 		}
1322 	}
1323 	/*
1324 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1325 	 * within-command recovery checks before receiving the payload.
1326 	 */
1327 	ret = iscsit_check_pre_dataout(cmd, buf);
1328 	if (ret == DATAOUT_WITHIN_COMMAND_RECOVERY)
1329 		return 0;
1330 	else if (ret == DATAOUT_CANNOT_RECOVER)
1331 		return -1;
1332 
1333 	rx_size += payload_length;
1334 	iov = &cmd->iov_data[0];
1335 
1336 	iov_ret = iscsit_map_iovec(cmd, iov, hdr->offset, payload_length);
1337 	if (iov_ret < 0)
1338 		return -1;
1339 
1340 	iov_count += iov_ret;
1341 
1342 	padding = ((-payload_length) & 3);
1343 	if (padding != 0) {
1344 		iov[iov_count].iov_base	= cmd->pad_bytes;
1345 		iov[iov_count++].iov_len = padding;
1346 		rx_size += padding;
1347 		pr_debug("Receiving %u padding bytes.\n", padding);
1348 	}
1349 
1350 	if (conn->conn_ops->DataDigest) {
1351 		iov[iov_count].iov_base = &checksum;
1352 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1353 		rx_size += ISCSI_CRC_LEN;
1354 	}
1355 
1356 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1357 
1358 	iscsit_unmap_iovec(cmd);
1359 
1360 	if (rx_got != rx_size)
1361 		return -1;
1362 
1363 	if (conn->conn_ops->DataDigest) {
1364 		u32 data_crc;
1365 
1366 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1367 						    hdr->offset, payload_length, padding,
1368 						    cmd->pad_bytes);
1369 
1370 		if (checksum != data_crc) {
1371 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1372 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1373 				" does not match computed 0x%08x\n",
1374 				hdr->itt, hdr->offset, payload_length,
1375 				hdr->datasn, checksum, data_crc);
1376 			data_crc_failed = 1;
1377 		} else {
1378 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1379 				" %u bytes of Data Out\n", checksum,
1380 				payload_length);
1381 		}
1382 	}
1383 	/*
1384 	 * Increment post receive data and CRC values or perform
1385 	 * within-command recovery.
1386 	 */
1387 	ret = iscsit_check_post_dataout(cmd, buf, data_crc_failed);
1388 	if ((ret == DATAOUT_NORMAL) || (ret == DATAOUT_WITHIN_COMMAND_RECOVERY))
1389 		return 0;
1390 	else if (ret == DATAOUT_SEND_R2T) {
1391 		iscsit_set_dataout_sequence_values(cmd);
1392 		iscsit_build_r2ts_for_cmd(cmd, conn, false);
1393 	} else if (ret == DATAOUT_SEND_TO_TRANSPORT) {
1394 		/*
1395 		 * Handle extra special case for out of order
1396 		 * Unsolicited Data Out.
1397 		 */
1398 		spin_lock_bh(&cmd->istate_lock);
1399 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1400 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1401 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1402 		spin_unlock_bh(&cmd->istate_lock);
1403 
1404 		iscsit_stop_dataout_timer(cmd);
1405 		if (ooo_cmdsn)
1406 			return 0;
1407 		target_execute_cmd(&cmd->se_cmd);
1408 		return 0;
1409 	} else /* DATAOUT_CANNOT_RECOVER */
1410 		return -1;
1411 
1412 	return 0;
1413 }
1414 
1415 static int iscsit_handle_nop_out(
1416 	struct iscsi_conn *conn,
1417 	unsigned char *buf)
1418 {
1419 	unsigned char *ping_data = NULL;
1420 	int cmdsn_ret, niov = 0, ret = 0, rx_got, rx_size;
1421 	u32 checksum, data_crc, padding = 0, payload_length;
1422 	struct iscsi_cmd *cmd = NULL;
1423 	struct kvec *iov = NULL;
1424 	struct iscsi_nopout *hdr;
1425 
1426 	hdr			= (struct iscsi_nopout *) buf;
1427 	payload_length		= ntoh24(hdr->dlength);
1428 	hdr->itt		= be32_to_cpu(hdr->itt);
1429 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1430 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1431 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1432 
1433 	if ((hdr->itt == 0xFFFFFFFF) && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1434 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1435 			" not set, protocol error.\n");
1436 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1437 					buf, conn);
1438 	}
1439 
1440 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1441 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1442 			" greater than MaxRecvDataSegmentLength: %u, protocol"
1443 			" error.\n", payload_length,
1444 			conn->conn_ops->MaxRecvDataSegmentLength);
1445 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1446 					buf, conn);
1447 	}
1448 
1449 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%09x,"
1450 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1451 		(hdr->itt == 0xFFFFFFFF) ? "Response" : "Request",
1452 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1453 		payload_length);
1454 	/*
1455 	 * This is not a response to a Unsolicited NopIN, which means
1456 	 * it can either be a NOPOUT ping request (with a valid ITT),
1457 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1458 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1459 	 * can contain ping data.
1460 	 */
1461 	if (hdr->ttt == 0xFFFFFFFF) {
1462 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1463 		if (!cmd)
1464 			return iscsit_add_reject(
1465 					ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1466 					1, buf, conn);
1467 
1468 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1469 		cmd->i_state		= ISTATE_SEND_NOPIN;
1470 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1471 						1 : 0);
1472 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1473 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1474 		cmd->cmd_sn		= hdr->cmdsn;
1475 		cmd->exp_stat_sn	= hdr->exp_statsn;
1476 		cmd->data_direction	= DMA_NONE;
1477 	}
1478 
1479 	if (payload_length && (hdr->ttt == 0xFFFFFFFF)) {
1480 		rx_size = payload_length;
1481 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1482 		if (!ping_data) {
1483 			pr_err("Unable to allocate memory for"
1484 				" NOPOUT ping data.\n");
1485 			ret = -1;
1486 			goto out;
1487 		}
1488 
1489 		iov = &cmd->iov_misc[0];
1490 		iov[niov].iov_base	= ping_data;
1491 		iov[niov++].iov_len	= payload_length;
1492 
1493 		padding = ((-payload_length) & 3);
1494 		if (padding != 0) {
1495 			pr_debug("Receiving %u additional bytes"
1496 				" for padding.\n", padding);
1497 			iov[niov].iov_base	= &cmd->pad_bytes;
1498 			iov[niov++].iov_len	= padding;
1499 			rx_size += padding;
1500 		}
1501 		if (conn->conn_ops->DataDigest) {
1502 			iov[niov].iov_base	= &checksum;
1503 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1504 			rx_size += ISCSI_CRC_LEN;
1505 		}
1506 
1507 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1508 		if (rx_got != rx_size) {
1509 			ret = -1;
1510 			goto out;
1511 		}
1512 
1513 		if (conn->conn_ops->DataDigest) {
1514 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1515 					ping_data, payload_length,
1516 					padding, cmd->pad_bytes,
1517 					(u8 *)&data_crc);
1518 
1519 			if (checksum != data_crc) {
1520 				pr_err("Ping data CRC32C DataDigest"
1521 				" 0x%08x does not match computed 0x%08x\n",
1522 					checksum, data_crc);
1523 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1524 					pr_err("Unable to recover from"
1525 					" NOPOUT Ping DataCRC failure while in"
1526 						" ERL=0.\n");
1527 					ret = -1;
1528 					goto out;
1529 				} else {
1530 					/*
1531 					 * Silently drop this PDU and let the
1532 					 * initiator plug the CmdSN gap.
1533 					 */
1534 					pr_debug("Dropping NOPOUT"
1535 					" Command CmdSN: 0x%08x due to"
1536 					" DataCRC error.\n", hdr->cmdsn);
1537 					ret = 0;
1538 					goto out;
1539 				}
1540 			} else {
1541 				pr_debug("Got CRC32C DataDigest"
1542 				" 0x%08x for %u bytes of ping data.\n",
1543 					checksum, payload_length);
1544 			}
1545 		}
1546 
1547 		ping_data[payload_length] = '\0';
1548 		/*
1549 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1550 		 */
1551 		cmd->buf_ptr = ping_data;
1552 		cmd->buf_ptr_size = payload_length;
1553 
1554 		pr_debug("Got %u bytes of NOPOUT ping"
1555 			" data.\n", payload_length);
1556 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1557 	}
1558 
1559 	if (hdr->itt != 0xFFFFFFFF) {
1560 		if (!cmd) {
1561 			pr_err("Checking CmdSN for NOPOUT,"
1562 				" but cmd is NULL!\n");
1563 			return -1;
1564 		}
1565 		/*
1566 		 * Initiator is expecting a NopIN ping reply,
1567 		 */
1568 		spin_lock_bh(&conn->cmd_lock);
1569 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1570 		spin_unlock_bh(&conn->cmd_lock);
1571 
1572 		iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1573 
1574 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1575 			iscsit_add_cmd_to_response_queue(cmd, conn,
1576 					cmd->i_state);
1577 			return 0;
1578 		}
1579 
1580 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1581 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1582 			ret = 0;
1583 			goto ping_out;
1584 		}
1585 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1586 			return iscsit_add_reject_from_cmd(
1587 					ISCSI_REASON_PROTOCOL_ERROR,
1588 					1, 0, buf, cmd);
1589 
1590 		return 0;
1591 	}
1592 
1593 	if (hdr->ttt != 0xFFFFFFFF) {
1594 		/*
1595 		 * This was a response to a unsolicited NOPIN ping.
1596 		 */
1597 		cmd = iscsit_find_cmd_from_ttt(conn, hdr->ttt);
1598 		if (!cmd)
1599 			return -1;
1600 
1601 		iscsit_stop_nopin_response_timer(conn);
1602 
1603 		cmd->i_state = ISTATE_REMOVE;
1604 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
1605 		iscsit_start_nopin_timer(conn);
1606 	} else {
1607 		/*
1608 		 * Initiator is not expecting a NOPIN is response.
1609 		 * Just ignore for now.
1610 		 *
1611 		 * iSCSI v19-91 10.18
1612 		 * "A NOP-OUT may also be used to confirm a changed
1613 		 *  ExpStatSN if another PDU will not be available
1614 		 *  for a long time."
1615 		 */
1616 		ret = 0;
1617 		goto out;
1618 	}
1619 
1620 	return 0;
1621 out:
1622 	if (cmd)
1623 		iscsit_release_cmd(cmd);
1624 ping_out:
1625 	kfree(ping_data);
1626 	return ret;
1627 }
1628 
1629 static int iscsit_handle_task_mgt_cmd(
1630 	struct iscsi_conn *conn,
1631 	unsigned char *buf)
1632 {
1633 	struct iscsi_cmd *cmd;
1634 	struct se_tmr_req *se_tmr;
1635 	struct iscsi_tmr_req *tmr_req;
1636 	struct iscsi_tm *hdr;
1637 	int out_of_order_cmdsn = 0;
1638 	int ret;
1639 	u8 function;
1640 
1641 	hdr			= (struct iscsi_tm *) buf;
1642 	hdr->itt		= be32_to_cpu(hdr->itt);
1643 	hdr->rtt		= be32_to_cpu(hdr->rtt);
1644 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1645 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1646 	hdr->refcmdsn		= be32_to_cpu(hdr->refcmdsn);
1647 	hdr->exp_datasn		= be32_to_cpu(hdr->exp_datasn);
1648 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1649 	function = hdr->flags;
1650 
1651 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1652 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1653 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1654 		hdr->rtt, hdr->refcmdsn, conn->cid);
1655 
1656 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1657 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1658 	     (hdr->rtt != ISCSI_RESERVED_TAG))) {
1659 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1660 		hdr->rtt = ISCSI_RESERVED_TAG;
1661 	}
1662 
1663 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1664 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1665 		pr_err("Task Management Request TASK_REASSIGN not"
1666 			" issued as immediate command, bad iSCSI Initiator"
1667 				"implementation\n");
1668 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1669 					buf, conn);
1670 	}
1671 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1672 	    (hdr->refcmdsn != ISCSI_RESERVED_TAG))
1673 		hdr->refcmdsn = ISCSI_RESERVED_TAG;
1674 
1675 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1676 	if (!cmd)
1677 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1678 					 1, buf, conn);
1679 
1680 	cmd->data_direction = DMA_NONE;
1681 
1682 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1683 	if (!cmd->tmr_req) {
1684 		pr_err("Unable to allocate memory for"
1685 			" Task Management command!\n");
1686 		return iscsit_add_reject_from_cmd(
1687 			ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1688 			1, 1, buf, cmd);
1689 	}
1690 
1691 	/*
1692 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1693 	 * LIO-Target $FABRIC_MOD
1694 	 */
1695 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1696 
1697 		u8 tcm_function;
1698 		int ret;
1699 
1700 		transport_init_se_cmd(&cmd->se_cmd,
1701 				      &lio_target_fabric_configfs->tf_ops,
1702 				      conn->sess->se_sess, 0, DMA_NONE,
1703 				      MSG_SIMPLE_TAG, &cmd->sense_buffer[0]);
1704 
1705 		switch (function) {
1706 		case ISCSI_TM_FUNC_ABORT_TASK:
1707 			tcm_function = TMR_ABORT_TASK;
1708 			break;
1709 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1710 			tcm_function = TMR_ABORT_TASK_SET;
1711 			break;
1712 		case ISCSI_TM_FUNC_CLEAR_ACA:
1713 			tcm_function = TMR_CLEAR_ACA;
1714 			break;
1715 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1716 			tcm_function = TMR_CLEAR_TASK_SET;
1717 			break;
1718 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1719 			tcm_function = TMR_LUN_RESET;
1720 			break;
1721 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1722 			tcm_function = TMR_TARGET_WARM_RESET;
1723 			break;
1724 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1725 			tcm_function = TMR_TARGET_COLD_RESET;
1726 			break;
1727 		default:
1728 			pr_err("Unknown iSCSI TMR Function:"
1729 			       " 0x%02x\n", function);
1730 			return iscsit_add_reject_from_cmd(
1731 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1732 				1, 1, buf, cmd);
1733 		}
1734 
1735 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1736 					 tcm_function, GFP_KERNEL);
1737 		if (ret < 0)
1738 			return iscsit_add_reject_from_cmd(
1739 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1740 				1, 1, buf, cmd);
1741 
1742 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1743 	}
1744 
1745 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1746 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1747 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1748 	cmd->init_task_tag	= hdr->itt;
1749 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1750 	cmd->cmd_sn		= hdr->cmdsn;
1751 	cmd->exp_stat_sn	= hdr->exp_statsn;
1752 	se_tmr			= cmd->se_cmd.se_tmr_req;
1753 	tmr_req			= cmd->tmr_req;
1754 	/*
1755 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1756 	 */
1757 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1758 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1759 					       scsilun_to_int(&hdr->lun));
1760 		if (ret < 0) {
1761 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1762 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1763 			goto attach;
1764 		}
1765 	}
1766 
1767 	switch (function) {
1768 	case ISCSI_TM_FUNC_ABORT_TASK:
1769 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1770 		if (se_tmr->response != ISCSI_TMF_RSP_COMPLETE) {
1771 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1772 			goto attach;
1773 		}
1774 		break;
1775 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1776 	case ISCSI_TM_FUNC_CLEAR_ACA:
1777 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1778 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1779 		break;
1780 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1781 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1782 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1783 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1784 			goto attach;
1785 		}
1786 		break;
1787 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1788 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1789 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1790 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1791 			goto attach;
1792 		}
1793 		break;
1794 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1795 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1796 		/*
1797 		 * Perform sanity checks on the ExpDataSN only if the
1798 		 * TASK_REASSIGN was successful.
1799 		 */
1800 		if (se_tmr->response != ISCSI_TMF_RSP_COMPLETE)
1801 			break;
1802 
1803 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1804 			return iscsit_add_reject_from_cmd(
1805 					ISCSI_REASON_BOOKMARK_INVALID, 1, 1,
1806 					buf, cmd);
1807 		break;
1808 	default:
1809 		pr_err("Unknown TMR function: 0x%02x, protocol"
1810 			" error.\n", function);
1811 		cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1812 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1813 		goto attach;
1814 	}
1815 
1816 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1817 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1818 		se_tmr->call_transport = 1;
1819 attach:
1820 	spin_lock_bh(&conn->cmd_lock);
1821 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1822 	spin_unlock_bh(&conn->cmd_lock);
1823 
1824 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1825 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1826 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1827 			out_of_order_cmdsn = 1;
1828 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1829 			return 0;
1830 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1831 			return iscsit_add_reject_from_cmd(
1832 					ISCSI_REASON_PROTOCOL_ERROR,
1833 					1, 0, buf, cmd);
1834 	}
1835 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1836 
1837 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1838 		return 0;
1839 	/*
1840 	 * Found the referenced task, send to transport for processing.
1841 	 */
1842 	if (se_tmr->call_transport)
1843 		return transport_generic_handle_tmr(&cmd->se_cmd);
1844 
1845 	/*
1846 	 * Could not find the referenced LUN, task, or Task Management
1847 	 * command not authorized or supported.  Change state and
1848 	 * let the tx_thread send the response.
1849 	 *
1850 	 * For connection recovery, this is also the default action for
1851 	 * TMR TASK_REASSIGN.
1852 	 */
1853 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1854 	return 0;
1855 }
1856 
1857 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1858 static int iscsit_handle_text_cmd(
1859 	struct iscsi_conn *conn,
1860 	unsigned char *buf)
1861 {
1862 	char *text_ptr, *text_in;
1863 	int cmdsn_ret, niov = 0, rx_got, rx_size;
1864 	u32 checksum = 0, data_crc = 0, payload_length;
1865 	u32 padding = 0, pad_bytes = 0, text_length = 0;
1866 	struct iscsi_cmd *cmd;
1867 	struct kvec iov[3];
1868 	struct iscsi_text *hdr;
1869 
1870 	hdr			= (struct iscsi_text *) buf;
1871 	payload_length		= ntoh24(hdr->dlength);
1872 	hdr->itt		= be32_to_cpu(hdr->itt);
1873 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1874 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1875 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1876 
1877 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1878 		pr_err("Unable to accept text parameter length: %u"
1879 			"greater than MaxRecvDataSegmentLength %u.\n",
1880 		       payload_length, conn->conn_ops->MaxRecvDataSegmentLength);
1881 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1882 					buf, conn);
1883 	}
1884 
1885 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1886 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1887 		hdr->exp_statsn, payload_length);
1888 
1889 	rx_size = text_length = payload_length;
1890 	if (text_length) {
1891 		text_in = kzalloc(text_length, GFP_KERNEL);
1892 		if (!text_in) {
1893 			pr_err("Unable to allocate memory for"
1894 				" incoming text parameters\n");
1895 			return -1;
1896 		}
1897 
1898 		memset(iov, 0, 3 * sizeof(struct kvec));
1899 		iov[niov].iov_base	= text_in;
1900 		iov[niov++].iov_len	= text_length;
1901 
1902 		padding = ((-payload_length) & 3);
1903 		if (padding != 0) {
1904 			iov[niov].iov_base = &pad_bytes;
1905 			iov[niov++].iov_len  = padding;
1906 			rx_size += padding;
1907 			pr_debug("Receiving %u additional bytes"
1908 					" for padding.\n", padding);
1909 		}
1910 		if (conn->conn_ops->DataDigest) {
1911 			iov[niov].iov_base	= &checksum;
1912 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1913 			rx_size += ISCSI_CRC_LEN;
1914 		}
1915 
1916 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
1917 		if (rx_got != rx_size) {
1918 			kfree(text_in);
1919 			return -1;
1920 		}
1921 
1922 		if (conn->conn_ops->DataDigest) {
1923 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1924 					text_in, text_length,
1925 					padding, (u8 *)&pad_bytes,
1926 					(u8 *)&data_crc);
1927 
1928 			if (checksum != data_crc) {
1929 				pr_err("Text data CRC32C DataDigest"
1930 					" 0x%08x does not match computed"
1931 					" 0x%08x\n", checksum, data_crc);
1932 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1933 					pr_err("Unable to recover from"
1934 					" Text Data digest failure while in"
1935 						" ERL=0.\n");
1936 					kfree(text_in);
1937 					return -1;
1938 				} else {
1939 					/*
1940 					 * Silently drop this PDU and let the
1941 					 * initiator plug the CmdSN gap.
1942 					 */
1943 					pr_debug("Dropping Text"
1944 					" Command CmdSN: 0x%08x due to"
1945 					" DataCRC error.\n", hdr->cmdsn);
1946 					kfree(text_in);
1947 					return 0;
1948 				}
1949 			} else {
1950 				pr_debug("Got CRC32C DataDigest"
1951 					" 0x%08x for %u bytes of text data.\n",
1952 						checksum, text_length);
1953 			}
1954 		}
1955 		text_in[text_length - 1] = '\0';
1956 		pr_debug("Successfully read %d bytes of text"
1957 				" data.\n", text_length);
1958 
1959 		if (strncmp("SendTargets", text_in, 11) != 0) {
1960 			pr_err("Received Text Data that is not"
1961 				" SendTargets, cannot continue.\n");
1962 			kfree(text_in);
1963 			return -1;
1964 		}
1965 		text_ptr = strchr(text_in, '=');
1966 		if (!text_ptr) {
1967 			pr_err("No \"=\" separator found in Text Data,"
1968 				"  cannot continue.\n");
1969 			kfree(text_in);
1970 			return -1;
1971 		}
1972 		if (strncmp("=All", text_ptr, 4) != 0) {
1973 			pr_err("Unable to locate All value for"
1974 				" SendTargets key,  cannot continue.\n");
1975 			kfree(text_in);
1976 			return -1;
1977 		}
1978 /*#warning Support SendTargets=(iSCSI Target Name/Nothing) values. */
1979 		kfree(text_in);
1980 	}
1981 
1982 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1983 	if (!cmd)
1984 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1985 					1, buf, conn);
1986 
1987 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1988 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1989 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1990 	conn->sess->init_task_tag = cmd->init_task_tag	= hdr->itt;
1991 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1992 	cmd->cmd_sn		= hdr->cmdsn;
1993 	cmd->exp_stat_sn	= hdr->exp_statsn;
1994 	cmd->data_direction	= DMA_NONE;
1995 
1996 	spin_lock_bh(&conn->cmd_lock);
1997 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1998 	spin_unlock_bh(&conn->cmd_lock);
1999 
2000 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
2001 
2002 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2003 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
2004 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2005 			return iscsit_add_reject_from_cmd(
2006 					ISCSI_REASON_PROTOCOL_ERROR,
2007 					1, 0, buf, cmd);
2008 
2009 		return 0;
2010 	}
2011 
2012 	return iscsit_execute_cmd(cmd, 0);
2013 }
2014 
2015 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2016 {
2017 	struct iscsi_conn *conn_p;
2018 	struct iscsi_session *sess = conn->sess;
2019 
2020 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2021 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2022 
2023 	atomic_set(&sess->session_logout, 1);
2024 	atomic_set(&conn->conn_logout_remove, 1);
2025 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2026 
2027 	iscsit_inc_conn_usage_count(conn);
2028 	iscsit_inc_session_usage_count(sess);
2029 
2030 	spin_lock_bh(&sess->conn_lock);
2031 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2032 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2033 			continue;
2034 
2035 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2036 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2037 	}
2038 	spin_unlock_bh(&sess->conn_lock);
2039 
2040 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2041 
2042 	return 0;
2043 }
2044 
2045 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2046 {
2047 	struct iscsi_conn *l_conn;
2048 	struct iscsi_session *sess = conn->sess;
2049 
2050 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2051 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2052 
2053 	/*
2054 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2055 	 * can arrive on a connection with a differing CID.
2056 	 */
2057 	if (conn->cid == cmd->logout_cid) {
2058 		spin_lock_bh(&conn->state_lock);
2059 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2060 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2061 
2062 		atomic_set(&conn->conn_logout_remove, 1);
2063 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2064 		iscsit_inc_conn_usage_count(conn);
2065 
2066 		spin_unlock_bh(&conn->state_lock);
2067 	} else {
2068 		/*
2069 		 * Handle all different cid CLOSECONNECTION requests in
2070 		 * iscsit_logout_post_handler_diffcid() as to give enough
2071 		 * time for any non immediate command's CmdSN to be
2072 		 * acknowledged on the connection in question.
2073 		 *
2074 		 * Here we simply make sure the CID is still around.
2075 		 */
2076 		l_conn = iscsit_get_conn_from_cid(sess,
2077 				cmd->logout_cid);
2078 		if (!l_conn) {
2079 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2080 			iscsit_add_cmd_to_response_queue(cmd, conn,
2081 					cmd->i_state);
2082 			return 0;
2083 		}
2084 
2085 		iscsit_dec_conn_usage_count(l_conn);
2086 	}
2087 
2088 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2089 
2090 	return 0;
2091 }
2092 
2093 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2094 {
2095 	struct iscsi_session *sess = conn->sess;
2096 
2097 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2098 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2099 
2100 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2101 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2102 			" while ERL!=2.\n");
2103 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2104 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2105 		return 0;
2106 	}
2107 
2108 	if (conn->cid == cmd->logout_cid) {
2109 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2110 			" with CID: %hu on CID: %hu, implementation error.\n",
2111 				cmd->logout_cid, conn->cid);
2112 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2113 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2114 		return 0;
2115 	}
2116 
2117 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2118 
2119 	return 0;
2120 }
2121 
2122 static int iscsit_handle_logout_cmd(
2123 	struct iscsi_conn *conn,
2124 	unsigned char *buf)
2125 {
2126 	int cmdsn_ret, logout_remove = 0;
2127 	u8 reason_code = 0;
2128 	struct iscsi_cmd *cmd;
2129 	struct iscsi_logout *hdr;
2130 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2131 
2132 	hdr			= (struct iscsi_logout *) buf;
2133 	reason_code		= (hdr->flags & 0x7f);
2134 	hdr->itt		= be32_to_cpu(hdr->itt);
2135 	hdr->cid		= be16_to_cpu(hdr->cid);
2136 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
2137 	hdr->exp_statsn	= be32_to_cpu(hdr->exp_statsn);
2138 
2139 	if (tiqn) {
2140 		spin_lock(&tiqn->logout_stats.lock);
2141 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2142 			tiqn->logout_stats.normal_logouts++;
2143 		else
2144 			tiqn->logout_stats.abnormal_logouts++;
2145 		spin_unlock(&tiqn->logout_stats.lock);
2146 	}
2147 
2148 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2149 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2150 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2151 		hdr->cid, conn->cid);
2152 
2153 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2154 		pr_err("Received logout request on connection that"
2155 			" is not in logged in state, ignoring request.\n");
2156 		return 0;
2157 	}
2158 
2159 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
2160 	if (!cmd)
2161 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES, 1,
2162 					buf, conn);
2163 
2164 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2165 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2166 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2167 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2168 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2169 	cmd->cmd_sn             = hdr->cmdsn;
2170 	cmd->exp_stat_sn        = hdr->exp_statsn;
2171 	cmd->logout_cid         = hdr->cid;
2172 	cmd->logout_reason      = reason_code;
2173 	cmd->data_direction     = DMA_NONE;
2174 
2175 	/*
2176 	 * We need to sleep in these cases (by returning 1) until the Logout
2177 	 * Response gets sent in the tx thread.
2178 	 */
2179 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2180 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2181 	    (hdr->cid == conn->cid)))
2182 		logout_remove = 1;
2183 
2184 	spin_lock_bh(&conn->cmd_lock);
2185 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2186 	spin_unlock_bh(&conn->cmd_lock);
2187 
2188 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2189 		iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
2190 
2191 	/*
2192 	 * Immediate commands are executed, well, immediately.
2193 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2194 	 */
2195 	if (cmd->immediate_cmd) {
2196 		int ret = iscsit_execute_cmd(cmd, 0);
2197 
2198 		if (ret < 0)
2199 			return ret;
2200 	} else {
2201 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
2202 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2203 			logout_remove = 0;
2204 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2205 			return iscsit_add_reject_from_cmd(
2206 				ISCSI_REASON_PROTOCOL_ERROR,
2207 				1, 0, buf, cmd);
2208 		}
2209 	}
2210 
2211 	return logout_remove;
2212 }
2213 
2214 static int iscsit_handle_snack(
2215 	struct iscsi_conn *conn,
2216 	unsigned char *buf)
2217 {
2218 	struct iscsi_snack *hdr;
2219 
2220 	hdr			= (struct iscsi_snack *) buf;
2221 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2222 	hdr->itt		= be32_to_cpu(hdr->itt);
2223 	hdr->ttt		= be32_to_cpu(hdr->ttt);
2224 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
2225 	hdr->begrun		= be32_to_cpu(hdr->begrun);
2226 	hdr->runlength		= be32_to_cpu(hdr->runlength);
2227 
2228 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2229 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2230 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2231 			hdr->begrun, hdr->runlength, conn->cid);
2232 
2233 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2234 		pr_err("Initiator sent SNACK request while in"
2235 			" ErrorRecoveryLevel=0.\n");
2236 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2237 					buf, conn);
2238 	}
2239 	/*
2240 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2241 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2242 	 */
2243 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2244 	case 0:
2245 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2246 			hdr->itt, hdr->ttt, hdr->begrun, hdr->runlength);
2247 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2248 		return iscsit_handle_status_snack(conn, hdr->itt, hdr->ttt,
2249 			hdr->begrun, hdr->runlength);
2250 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2251 		return iscsit_handle_data_ack(conn, hdr->ttt, hdr->begrun,
2252 			hdr->runlength);
2253 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2254 		/* FIXME: Support R-Data SNACK */
2255 		pr_err("R-Data SNACK Not Supported.\n");
2256 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2257 					buf, conn);
2258 	default:
2259 		pr_err("Unknown SNACK type 0x%02x, protocol"
2260 			" error.\n", hdr->flags & 0x0f);
2261 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2262 					buf, conn);
2263 	}
2264 
2265 	return 0;
2266 }
2267 
2268 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2269 {
2270 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2271 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2272 		wait_for_completion_interruptible_timeout(
2273 					&conn->rx_half_close_comp,
2274 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2275 	}
2276 }
2277 
2278 static int iscsit_handle_immediate_data(
2279 	struct iscsi_cmd *cmd,
2280 	unsigned char *buf,
2281 	u32 length)
2282 {
2283 	int iov_ret, rx_got = 0, rx_size = 0;
2284 	u32 checksum, iov_count = 0, padding = 0;
2285 	struct iscsi_conn *conn = cmd->conn;
2286 	struct kvec *iov;
2287 
2288 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2289 	if (iov_ret < 0)
2290 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2291 
2292 	rx_size = length;
2293 	iov_count = iov_ret;
2294 	iov = &cmd->iov_data[0];
2295 
2296 	padding = ((-length) & 3);
2297 	if (padding != 0) {
2298 		iov[iov_count].iov_base	= cmd->pad_bytes;
2299 		iov[iov_count++].iov_len = padding;
2300 		rx_size += padding;
2301 	}
2302 
2303 	if (conn->conn_ops->DataDigest) {
2304 		iov[iov_count].iov_base		= &checksum;
2305 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2306 		rx_size += ISCSI_CRC_LEN;
2307 	}
2308 
2309 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2310 
2311 	iscsit_unmap_iovec(cmd);
2312 
2313 	if (rx_got != rx_size) {
2314 		iscsit_rx_thread_wait_for_tcp(conn);
2315 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2316 	}
2317 
2318 	if (conn->conn_ops->DataDigest) {
2319 		u32 data_crc;
2320 
2321 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2322 						    cmd->write_data_done, length, padding,
2323 						    cmd->pad_bytes);
2324 
2325 		if (checksum != data_crc) {
2326 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2327 				" does not match computed 0x%08x\n", checksum,
2328 				data_crc);
2329 
2330 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2331 				pr_err("Unable to recover from"
2332 					" Immediate Data digest failure while"
2333 					" in ERL=0.\n");
2334 				iscsit_add_reject_from_cmd(
2335 						ISCSI_REASON_DATA_DIGEST_ERROR,
2336 						1, 0, buf, cmd);
2337 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2338 			} else {
2339 				iscsit_add_reject_from_cmd(
2340 						ISCSI_REASON_DATA_DIGEST_ERROR,
2341 						0, 0, buf, cmd);
2342 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2343 			}
2344 		} else {
2345 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2346 				" %u bytes of Immediate Data\n", checksum,
2347 				length);
2348 		}
2349 	}
2350 
2351 	cmd->write_data_done += length;
2352 
2353 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2354 		spin_lock_bh(&cmd->istate_lock);
2355 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2356 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2357 		spin_unlock_bh(&cmd->istate_lock);
2358 	}
2359 
2360 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2361 }
2362 
2363 /*
2364  *	Called with sess->conn_lock held.
2365  */
2366 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2367 	with active network interface */
2368 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2369 {
2370 	struct iscsi_cmd *cmd;
2371 	struct iscsi_conn *conn_p;
2372 
2373 	/*
2374 	 * Only send a Asynchronous Message on connections whos network
2375 	 * interface is still functional.
2376 	 */
2377 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2378 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2379 			iscsit_inc_conn_usage_count(conn_p);
2380 			break;
2381 		}
2382 	}
2383 
2384 	if (!conn_p)
2385 		return;
2386 
2387 	cmd = iscsit_allocate_cmd(conn_p, GFP_KERNEL);
2388 	if (!cmd) {
2389 		iscsit_dec_conn_usage_count(conn_p);
2390 		return;
2391 	}
2392 
2393 	cmd->logout_cid = conn->cid;
2394 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2395 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2396 
2397 	spin_lock_bh(&conn_p->cmd_lock);
2398 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2399 	spin_unlock_bh(&conn_p->cmd_lock);
2400 
2401 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2402 	iscsit_dec_conn_usage_count(conn_p);
2403 }
2404 
2405 static int iscsit_send_conn_drop_async_message(
2406 	struct iscsi_cmd *cmd,
2407 	struct iscsi_conn *conn)
2408 {
2409 	struct iscsi_async *hdr;
2410 
2411 	cmd->tx_size = ISCSI_HDR_LEN;
2412 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2413 
2414 	hdr			= (struct iscsi_async *) cmd->pdu;
2415 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2416 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2417 	cmd->init_task_tag	= 0xFFFFFFFF;
2418 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2419 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2420 	cmd->stat_sn		= conn->stat_sn++;
2421 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2422 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2423 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2424 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2425 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2426 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2427 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2428 
2429 	if (conn->conn_ops->HeaderDigest) {
2430 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2431 
2432 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2433 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2434 				0, NULL, (u8 *)header_digest);
2435 
2436 		cmd->tx_size += ISCSI_CRC_LEN;
2437 		pr_debug("Attaching CRC32C HeaderDigest to"
2438 			" Async Message 0x%08x\n", *header_digest);
2439 	}
2440 
2441 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2442 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2443 	cmd->iov_misc_count		= 1;
2444 
2445 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2446 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2447 			cmd->logout_cid, conn->cid);
2448 	return 0;
2449 }
2450 
2451 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2452 {
2453 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2454 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2455 		wait_for_completion_interruptible_timeout(
2456 					&conn->tx_half_close_comp,
2457 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2458 	}
2459 }
2460 
2461 static int iscsit_send_data_in(
2462 	struct iscsi_cmd *cmd,
2463 	struct iscsi_conn *conn)
2464 {
2465 	int iov_ret = 0, set_statsn = 0;
2466 	u32 iov_count = 0, tx_size = 0;
2467 	struct iscsi_datain datain;
2468 	struct iscsi_datain_req *dr;
2469 	struct iscsi_data_rsp *hdr;
2470 	struct kvec *iov;
2471 	int eodr = 0;
2472 	int ret;
2473 
2474 	memset(&datain, 0, sizeof(struct iscsi_datain));
2475 	dr = iscsit_get_datain_values(cmd, &datain);
2476 	if (!dr) {
2477 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2478 				cmd->init_task_tag);
2479 		return -1;
2480 	}
2481 
2482 	/*
2483 	 * Be paranoid and double check the logic for now.
2484 	 */
2485 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2486 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2487 			" datain.length: %u exceeds cmd->data_length: %u\n",
2488 			cmd->init_task_tag, datain.offset, datain.length,
2489 				cmd->se_cmd.data_length);
2490 		return -1;
2491 	}
2492 
2493 	spin_lock_bh(&conn->sess->session_stats_lock);
2494 	conn->sess->tx_data_octets += datain.length;
2495 	if (conn->sess->se_sess->se_node_acl) {
2496 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
2497 		conn->sess->se_sess->se_node_acl->read_bytes += datain.length;
2498 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
2499 	}
2500 	spin_unlock_bh(&conn->sess->session_stats_lock);
2501 	/*
2502 	 * Special case for successfully execution w/ both DATAIN
2503 	 * and Sense Data.
2504 	 */
2505 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2506 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2507 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2508 	else {
2509 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2510 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2511 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2512 			cmd->stat_sn = conn->stat_sn++;
2513 			set_statsn = 1;
2514 		} else if (dr->dr_complete ==
2515 				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2516 			set_statsn = 1;
2517 	}
2518 
2519 	hdr	= (struct iscsi_data_rsp *) cmd->pdu;
2520 	memset(hdr, 0, ISCSI_HDR_LEN);
2521 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2522 	hdr->flags		= datain.flags;
2523 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2524 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2525 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2526 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2527 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2528 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2529 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2530 		}
2531 	}
2532 	hton24(hdr->dlength, datain.length);
2533 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2534 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2535 				(struct scsi_lun *)&hdr->lun);
2536 	else
2537 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2538 
2539 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2540 	hdr->ttt		= (hdr->flags & ISCSI_FLAG_DATA_ACK) ?
2541 				   cpu_to_be32(cmd->targ_xfer_tag) :
2542 				   0xFFFFFFFF;
2543 	hdr->statsn		= (set_statsn) ? cpu_to_be32(cmd->stat_sn) :
2544 						0xFFFFFFFF;
2545 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2546 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2547 	hdr->datasn		= cpu_to_be32(datain.data_sn);
2548 	hdr->offset		= cpu_to_be32(datain.offset);
2549 
2550 	iov = &cmd->iov_data[0];
2551 	iov[iov_count].iov_base	= cmd->pdu;
2552 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2553 	tx_size += ISCSI_HDR_LEN;
2554 
2555 	if (conn->conn_ops->HeaderDigest) {
2556 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2557 
2558 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2559 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2560 				0, NULL, (u8 *)header_digest);
2561 
2562 		iov[0].iov_len += ISCSI_CRC_LEN;
2563 		tx_size += ISCSI_CRC_LEN;
2564 
2565 		pr_debug("Attaching CRC32 HeaderDigest"
2566 			" for DataIN PDU 0x%08x\n", *header_digest);
2567 	}
2568 
2569 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1], datain.offset, datain.length);
2570 	if (iov_ret < 0)
2571 		return -1;
2572 
2573 	iov_count += iov_ret;
2574 	tx_size += datain.length;
2575 
2576 	cmd->padding = ((-datain.length) & 3);
2577 	if (cmd->padding) {
2578 		iov[iov_count].iov_base		= cmd->pad_bytes;
2579 		iov[iov_count++].iov_len	= cmd->padding;
2580 		tx_size += cmd->padding;
2581 
2582 		pr_debug("Attaching %u padding bytes\n",
2583 				cmd->padding);
2584 	}
2585 	if (conn->conn_ops->DataDigest) {
2586 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2587 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2588 
2589 		iov[iov_count].iov_base	= &cmd->data_crc;
2590 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2591 		tx_size += ISCSI_CRC_LEN;
2592 
2593 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2594 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2595 	}
2596 
2597 	cmd->iov_data_count = iov_count;
2598 	cmd->tx_size = tx_size;
2599 
2600 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2601 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2602 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2603 		ntohl(hdr->offset), datain.length, conn->cid);
2604 
2605 	/* sendpage is preferred but can't insert markers */
2606 	if (!conn->conn_ops->IFMarker)
2607 		ret = iscsit_fe_sendpage_sg(cmd, conn);
2608 	else
2609 		ret = iscsit_send_tx_data(cmd, conn, 0);
2610 
2611 	iscsit_unmap_iovec(cmd);
2612 
2613 	if (ret < 0) {
2614 		iscsit_tx_thread_wait_for_tcp(conn);
2615 		return ret;
2616 	}
2617 
2618 	if (dr->dr_complete) {
2619 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2620 				2 : 1;
2621 		iscsit_free_datain_req(cmd, dr);
2622 	}
2623 
2624 	return eodr;
2625 }
2626 
2627 static int iscsit_send_logout_response(
2628 	struct iscsi_cmd *cmd,
2629 	struct iscsi_conn *conn)
2630 {
2631 	int niov = 0, tx_size;
2632 	struct iscsi_conn *logout_conn = NULL;
2633 	struct iscsi_conn_recovery *cr = NULL;
2634 	struct iscsi_session *sess = conn->sess;
2635 	struct kvec *iov;
2636 	struct iscsi_logout_rsp *hdr;
2637 	/*
2638 	 * The actual shutting down of Sessions and/or Connections
2639 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2640 	 * is done in scsi_logout_post_handler().
2641 	 */
2642 	switch (cmd->logout_reason) {
2643 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2644 		pr_debug("iSCSI session logout successful, setting"
2645 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2646 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2647 		break;
2648 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2649 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2650 			break;
2651 		/*
2652 		 * For CLOSECONNECTION logout requests carrying
2653 		 * a matching logout CID -> local CID, the reference
2654 		 * for the local CID will have been incremented in
2655 		 * iscsi_logout_closeconnection().
2656 		 *
2657 		 * For CLOSECONNECTION logout requests carrying
2658 		 * a different CID than the connection it arrived
2659 		 * on, the connection responding to cmd->logout_cid
2660 		 * is stopped in iscsit_logout_post_handler_diffcid().
2661 		 */
2662 
2663 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2664 			" successful.\n", cmd->logout_cid, conn->cid);
2665 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2666 		break;
2667 	case ISCSI_LOGOUT_REASON_RECOVERY:
2668 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2669 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2670 			break;
2671 		/*
2672 		 * If the connection is still active from our point of view
2673 		 * force connection recovery to occur.
2674 		 */
2675 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2676 				cmd->logout_cid);
2677 		if (logout_conn) {
2678 			iscsit_connection_reinstatement_rcfr(logout_conn);
2679 			iscsit_dec_conn_usage_count(logout_conn);
2680 		}
2681 
2682 		cr = iscsit_get_inactive_connection_recovery_entry(
2683 				conn->sess, cmd->logout_cid);
2684 		if (!cr) {
2685 			pr_err("Unable to locate CID: %hu for"
2686 			" REMOVECONNFORRECOVERY Logout Request.\n",
2687 				cmd->logout_cid);
2688 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2689 			break;
2690 		}
2691 
2692 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2693 
2694 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2695 			" for recovery for CID: %hu on CID: %hu successful.\n",
2696 				cmd->logout_cid, conn->cid);
2697 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2698 		break;
2699 	default:
2700 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2701 				cmd->logout_reason);
2702 		return -1;
2703 	}
2704 
2705 	tx_size = ISCSI_HDR_LEN;
2706 	hdr			= (struct iscsi_logout_rsp *)cmd->pdu;
2707 	memset(hdr, 0, ISCSI_HDR_LEN);
2708 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2709 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2710 	hdr->response		= cmd->logout_response;
2711 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2712 	cmd->stat_sn		= conn->stat_sn++;
2713 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2714 
2715 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2716 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2717 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2718 
2719 	iov = &cmd->iov_misc[0];
2720 	iov[niov].iov_base	= cmd->pdu;
2721 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2722 
2723 	if (conn->conn_ops->HeaderDigest) {
2724 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2725 
2726 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2727 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2728 				0, NULL, (u8 *)header_digest);
2729 
2730 		iov[0].iov_len += ISCSI_CRC_LEN;
2731 		tx_size += ISCSI_CRC_LEN;
2732 		pr_debug("Attaching CRC32C HeaderDigest to"
2733 			" Logout Response 0x%08x\n", *header_digest);
2734 	}
2735 	cmd->iov_misc_count = niov;
2736 	cmd->tx_size = tx_size;
2737 
2738 	pr_debug("Sending Logout Response ITT: 0x%08x StatSN:"
2739 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2740 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2741 		cmd->logout_cid, conn->cid);
2742 
2743 	return 0;
2744 }
2745 
2746 /*
2747  *	Unsolicited NOPIN, either requesting a response or not.
2748  */
2749 static int iscsit_send_unsolicited_nopin(
2750 	struct iscsi_cmd *cmd,
2751 	struct iscsi_conn *conn,
2752 	int want_response)
2753 {
2754 	int tx_size = ISCSI_HDR_LEN;
2755 	struct iscsi_nopin *hdr;
2756 	int ret;
2757 
2758 	hdr			= (struct iscsi_nopin *) cmd->pdu;
2759 	memset(hdr, 0, ISCSI_HDR_LEN);
2760 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2761 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2762 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2763 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2764 	cmd->stat_sn		= conn->stat_sn;
2765 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2766 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2767 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2768 
2769 	if (conn->conn_ops->HeaderDigest) {
2770 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2771 
2772 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2773 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2774 				0, NULL, (u8 *)header_digest);
2775 
2776 		tx_size += ISCSI_CRC_LEN;
2777 		pr_debug("Attaching CRC32C HeaderDigest to"
2778 			" NopIN 0x%08x\n", *header_digest);
2779 	}
2780 
2781 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2782 	cmd->iov_misc[0].iov_len	= tx_size;
2783 	cmd->iov_misc_count	= 1;
2784 	cmd->tx_size		= tx_size;
2785 
2786 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2787 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2788 
2789 	ret = iscsit_send_tx_data(cmd, conn, 1);
2790 	if (ret < 0) {
2791 		iscsit_tx_thread_wait_for_tcp(conn);
2792 		return ret;
2793 	}
2794 
2795 	spin_lock_bh(&cmd->istate_lock);
2796 	cmd->i_state = want_response ?
2797 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2798 	spin_unlock_bh(&cmd->istate_lock);
2799 
2800 	return 0;
2801 }
2802 
2803 static int iscsit_send_nopin_response(
2804 	struct iscsi_cmd *cmd,
2805 	struct iscsi_conn *conn)
2806 {
2807 	int niov = 0, tx_size;
2808 	u32 padding = 0;
2809 	struct kvec *iov;
2810 	struct iscsi_nopin *hdr;
2811 
2812 	tx_size = ISCSI_HDR_LEN;
2813 	hdr			= (struct iscsi_nopin *) cmd->pdu;
2814 	memset(hdr, 0, ISCSI_HDR_LEN);
2815 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2816 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2817 	hton24(hdr->dlength, cmd->buf_ptr_size);
2818 	put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2819 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2820 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2821 	cmd->stat_sn		= conn->stat_sn++;
2822 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2823 
2824 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2825 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2826 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2827 
2828 	iov = &cmd->iov_misc[0];
2829 	iov[niov].iov_base	= cmd->pdu;
2830 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2831 
2832 	if (conn->conn_ops->HeaderDigest) {
2833 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2834 
2835 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2836 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2837 				0, NULL, (u8 *)header_digest);
2838 
2839 		iov[0].iov_len += ISCSI_CRC_LEN;
2840 		tx_size += ISCSI_CRC_LEN;
2841 		pr_debug("Attaching CRC32C HeaderDigest"
2842 			" to NopIn 0x%08x\n", *header_digest);
2843 	}
2844 
2845 	/*
2846 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2847 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2848 	 */
2849 	if (cmd->buf_ptr_size) {
2850 		iov[niov].iov_base	= cmd->buf_ptr;
2851 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2852 		tx_size += cmd->buf_ptr_size;
2853 
2854 		pr_debug("Echoing back %u bytes of ping"
2855 			" data.\n", cmd->buf_ptr_size);
2856 
2857 		padding = ((-cmd->buf_ptr_size) & 3);
2858 		if (padding != 0) {
2859 			iov[niov].iov_base = &cmd->pad_bytes;
2860 			iov[niov++].iov_len = padding;
2861 			tx_size += padding;
2862 			pr_debug("Attaching %u additional"
2863 				" padding bytes.\n", padding);
2864 		}
2865 		if (conn->conn_ops->DataDigest) {
2866 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2867 				cmd->buf_ptr, cmd->buf_ptr_size,
2868 				padding, (u8 *)&cmd->pad_bytes,
2869 				(u8 *)&cmd->data_crc);
2870 
2871 			iov[niov].iov_base = &cmd->data_crc;
2872 			iov[niov++].iov_len = ISCSI_CRC_LEN;
2873 			tx_size += ISCSI_CRC_LEN;
2874 			pr_debug("Attached DataDigest for %u"
2875 				" bytes of ping data, CRC 0x%08x\n",
2876 				cmd->buf_ptr_size, cmd->data_crc);
2877 		}
2878 	}
2879 
2880 	cmd->iov_misc_count = niov;
2881 	cmd->tx_size = tx_size;
2882 
2883 	pr_debug("Sending NOPIN Response ITT: 0x%08x, TTT:"
2884 		" 0x%08x, StatSN: 0x%08x, Length %u\n", cmd->init_task_tag,
2885 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2886 
2887 	return 0;
2888 }
2889 
2890 static int iscsit_send_r2t(
2891 	struct iscsi_cmd *cmd,
2892 	struct iscsi_conn *conn)
2893 {
2894 	int tx_size = 0;
2895 	struct iscsi_r2t *r2t;
2896 	struct iscsi_r2t_rsp *hdr;
2897 	int ret;
2898 
2899 	r2t = iscsit_get_r2t_from_list(cmd);
2900 	if (!r2t)
2901 		return -1;
2902 
2903 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
2904 	memset(hdr, 0, ISCSI_HDR_LEN);
2905 	hdr->opcode		= ISCSI_OP_R2T;
2906 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2907 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2908 			(struct scsi_lun *)&hdr->lun);
2909 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2910 	spin_lock_bh(&conn->sess->ttt_lock);
2911 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
2912 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
2913 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
2914 	spin_unlock_bh(&conn->sess->ttt_lock);
2915 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
2916 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
2917 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2918 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2919 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
2920 	hdr->data_offset	= cpu_to_be32(r2t->offset);
2921 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
2922 
2923 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2924 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
2925 	tx_size += ISCSI_HDR_LEN;
2926 
2927 	if (conn->conn_ops->HeaderDigest) {
2928 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2929 
2930 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2931 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2932 				0, NULL, (u8 *)header_digest);
2933 
2934 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
2935 		tx_size += ISCSI_CRC_LEN;
2936 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
2937 			" PDU 0x%08x\n", *header_digest);
2938 	}
2939 
2940 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
2941 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
2942 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
2943 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
2944 			r2t->offset, r2t->xfer_len, conn->cid);
2945 
2946 	cmd->iov_misc_count = 1;
2947 	cmd->tx_size = tx_size;
2948 
2949 	spin_lock_bh(&cmd->r2t_lock);
2950 	r2t->sent_r2t = 1;
2951 	spin_unlock_bh(&cmd->r2t_lock);
2952 
2953 	ret = iscsit_send_tx_data(cmd, conn, 1);
2954 	if (ret < 0) {
2955 		iscsit_tx_thread_wait_for_tcp(conn);
2956 		return ret;
2957 	}
2958 
2959 	spin_lock_bh(&cmd->dataout_timeout_lock);
2960 	iscsit_start_dataout_timer(cmd, conn);
2961 	spin_unlock_bh(&cmd->dataout_timeout_lock);
2962 
2963 	return 0;
2964 }
2965 
2966 /*
2967  *	@recovery: If called from iscsi_task_reassign_complete_write() for
2968  *		connection recovery.
2969  */
2970 int iscsit_build_r2ts_for_cmd(
2971 	struct iscsi_cmd *cmd,
2972 	struct iscsi_conn *conn,
2973 	bool recovery)
2974 {
2975 	int first_r2t = 1;
2976 	u32 offset = 0, xfer_len = 0;
2977 
2978 	spin_lock_bh(&cmd->r2t_lock);
2979 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
2980 		spin_unlock_bh(&cmd->r2t_lock);
2981 		return 0;
2982 	}
2983 
2984 	if (conn->sess->sess_ops->DataSequenceInOrder &&
2985 	    !recovery)
2986 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
2987 
2988 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
2989 		if (conn->sess->sess_ops->DataSequenceInOrder) {
2990 			offset = cmd->r2t_offset;
2991 
2992 			if (first_r2t && recovery) {
2993 				int new_data_end = offset +
2994 					conn->sess->sess_ops->MaxBurstLength -
2995 					cmd->next_burst_len;
2996 
2997 				if (new_data_end > cmd->se_cmd.data_length)
2998 					xfer_len = cmd->se_cmd.data_length - offset;
2999 				else
3000 					xfer_len =
3001 						conn->sess->sess_ops->MaxBurstLength -
3002 						cmd->next_burst_len;
3003 			} else {
3004 				int new_data_end = offset +
3005 					conn->sess->sess_ops->MaxBurstLength;
3006 
3007 				if (new_data_end > cmd->se_cmd.data_length)
3008 					xfer_len = cmd->se_cmd.data_length - offset;
3009 				else
3010 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3011 			}
3012 			cmd->r2t_offset += xfer_len;
3013 
3014 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3015 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3016 		} else {
3017 			struct iscsi_seq *seq;
3018 
3019 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3020 			if (!seq) {
3021 				spin_unlock_bh(&cmd->r2t_lock);
3022 				return -1;
3023 			}
3024 
3025 			offset = seq->offset;
3026 			xfer_len = seq->xfer_len;
3027 
3028 			if (cmd->seq_send_order == cmd->seq_count)
3029 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3030 		}
3031 		cmd->outstanding_r2ts++;
3032 		first_r2t = 0;
3033 
3034 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3035 			spin_unlock_bh(&cmd->r2t_lock);
3036 			return -1;
3037 		}
3038 
3039 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3040 			break;
3041 	}
3042 	spin_unlock_bh(&cmd->r2t_lock);
3043 
3044 	return 0;
3045 }
3046 
3047 static int iscsit_send_status(
3048 	struct iscsi_cmd *cmd,
3049 	struct iscsi_conn *conn)
3050 {
3051 	u8 iov_count = 0, recovery;
3052 	u32 padding = 0, tx_size = 0;
3053 	struct iscsi_scsi_rsp *hdr;
3054 	struct kvec *iov;
3055 
3056 	recovery = (cmd->i_state != ISTATE_SEND_STATUS);
3057 	if (!recovery)
3058 		cmd->stat_sn = conn->stat_sn++;
3059 
3060 	spin_lock_bh(&conn->sess->session_stats_lock);
3061 	conn->sess->rsp_pdus++;
3062 	spin_unlock_bh(&conn->sess->session_stats_lock);
3063 
3064 	hdr			= (struct iscsi_scsi_rsp *) cmd->pdu;
3065 	memset(hdr, 0, ISCSI_HDR_LEN);
3066 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3067 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3068 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3069 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3070 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3071 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3072 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3073 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3074 	}
3075 	hdr->response		= cmd->iscsi_response;
3076 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3077 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3078 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3079 
3080 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3081 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3082 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3083 
3084 	iov = &cmd->iov_misc[0];
3085 	iov[iov_count].iov_base	= cmd->pdu;
3086 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3087 	tx_size += ISCSI_HDR_LEN;
3088 
3089 	/*
3090 	 * Attach SENSE DATA payload to iSCSI Response PDU
3091 	 */
3092 	if (cmd->se_cmd.sense_buffer &&
3093 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3094 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3095 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3096 		hton24(hdr->dlength, cmd->se_cmd.scsi_sense_length);
3097 		iov[iov_count].iov_base	= cmd->se_cmd.sense_buffer;
3098 		iov[iov_count++].iov_len =
3099 				(cmd->se_cmd.scsi_sense_length + padding);
3100 		tx_size += cmd->se_cmd.scsi_sense_length;
3101 
3102 		if (padding) {
3103 			memset(cmd->se_cmd.sense_buffer +
3104 				cmd->se_cmd.scsi_sense_length, 0, padding);
3105 			tx_size += padding;
3106 			pr_debug("Adding %u bytes of padding to"
3107 				" SENSE.\n", padding);
3108 		}
3109 
3110 		if (conn->conn_ops->DataDigest) {
3111 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3112 				cmd->se_cmd.sense_buffer,
3113 				(cmd->se_cmd.scsi_sense_length + padding),
3114 				0, NULL, (u8 *)&cmd->data_crc);
3115 
3116 			iov[iov_count].iov_base    = &cmd->data_crc;
3117 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3118 			tx_size += ISCSI_CRC_LEN;
3119 
3120 			pr_debug("Attaching CRC32 DataDigest for"
3121 				" SENSE, %u bytes CRC 0x%08x\n",
3122 				(cmd->se_cmd.scsi_sense_length + padding),
3123 				cmd->data_crc);
3124 		}
3125 
3126 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3127 				" Response PDU\n",
3128 				cmd->se_cmd.scsi_sense_length);
3129 	}
3130 
3131 	if (conn->conn_ops->HeaderDigest) {
3132 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3133 
3134 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3135 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3136 				0, NULL, (u8 *)header_digest);
3137 
3138 		iov[0].iov_len += ISCSI_CRC_LEN;
3139 		tx_size += ISCSI_CRC_LEN;
3140 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3141 				" PDU 0x%08x\n", *header_digest);
3142 	}
3143 
3144 	cmd->iov_misc_count = iov_count;
3145 	cmd->tx_size = tx_size;
3146 
3147 	pr_debug("Built %sSCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3148 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3149 		(!recovery) ? "" : "Recovery ", cmd->init_task_tag,
3150 		cmd->stat_sn, 0x00, cmd->se_cmd.scsi_status, conn->cid);
3151 
3152 	return 0;
3153 }
3154 
3155 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3156 {
3157 	switch (se_tmr->response) {
3158 	case TMR_FUNCTION_COMPLETE:
3159 		return ISCSI_TMF_RSP_COMPLETE;
3160 	case TMR_TASK_DOES_NOT_EXIST:
3161 		return ISCSI_TMF_RSP_NO_TASK;
3162 	case TMR_LUN_DOES_NOT_EXIST:
3163 		return ISCSI_TMF_RSP_NO_LUN;
3164 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3165 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3166 	case TMR_FUNCTION_AUTHORIZATION_FAILED:
3167 		return ISCSI_TMF_RSP_AUTH_FAILED;
3168 	case TMR_FUNCTION_REJECTED:
3169 	default:
3170 		return ISCSI_TMF_RSP_REJECTED;
3171 	}
3172 }
3173 
3174 static int iscsit_send_task_mgt_rsp(
3175 	struct iscsi_cmd *cmd,
3176 	struct iscsi_conn *conn)
3177 {
3178 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3179 	struct iscsi_tm_rsp *hdr;
3180 	u32 tx_size = 0;
3181 
3182 	hdr			= (struct iscsi_tm_rsp *) cmd->pdu;
3183 	memset(hdr, 0, ISCSI_HDR_LEN);
3184 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3185 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3186 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3187 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3188 	cmd->stat_sn		= conn->stat_sn++;
3189 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3190 
3191 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3192 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3193 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3194 
3195 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3196 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3197 	tx_size += ISCSI_HDR_LEN;
3198 
3199 	if (conn->conn_ops->HeaderDigest) {
3200 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3201 
3202 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3203 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3204 				0, NULL, (u8 *)header_digest);
3205 
3206 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3207 		tx_size += ISCSI_CRC_LEN;
3208 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3209 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3210 	}
3211 
3212 	cmd->iov_misc_count = 1;
3213 	cmd->tx_size = tx_size;
3214 
3215 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3216 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3217 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3218 
3219 	return 0;
3220 }
3221 
3222 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3223 {
3224 	bool ret = false;
3225 
3226 	if (np->np_sockaddr.ss_family == AF_INET6) {
3227 		const struct sockaddr_in6 sin6 = {
3228 			.sin6_addr = IN6ADDR_ANY_INIT };
3229 		struct sockaddr_in6 *sock_in6 =
3230 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3231 
3232 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3233 				sin6.sin6_addr.s6_addr, 16))
3234 			ret = true;
3235 	} else {
3236 		struct sockaddr_in * sock_in =
3237 			(struct sockaddr_in *)&np->np_sockaddr;
3238 
3239 		if (sock_in->sin_addr.s_addr == INADDR_ANY)
3240 			ret = true;
3241 	}
3242 
3243 	return ret;
3244 }
3245 
3246 #define SENDTARGETS_BUF_LIMIT 32768U
3247 
3248 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3249 {
3250 	char *payload = NULL;
3251 	struct iscsi_conn *conn = cmd->conn;
3252 	struct iscsi_portal_group *tpg;
3253 	struct iscsi_tiqn *tiqn;
3254 	struct iscsi_tpg_np *tpg_np;
3255 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3256 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3257 
3258 	buffer_len = max(conn->conn_ops->MaxRecvDataSegmentLength,
3259 			 SENDTARGETS_BUF_LIMIT);
3260 
3261 	payload = kzalloc(buffer_len, GFP_KERNEL);
3262 	if (!payload) {
3263 		pr_err("Unable to allocate memory for sendtargets"
3264 				" response.\n");
3265 		return -ENOMEM;
3266 	}
3267 
3268 	spin_lock(&tiqn_lock);
3269 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3270 		len = sprintf(buf, "TargetName=%s", tiqn->tiqn);
3271 		len += 1;
3272 
3273 		if ((len + payload_len) > buffer_len) {
3274 			spin_unlock(&tiqn->tiqn_tpg_lock);
3275 			end_of_buf = 1;
3276 			goto eob;
3277 		}
3278 		memcpy(payload + payload_len, buf, len);
3279 		payload_len += len;
3280 
3281 		spin_lock(&tiqn->tiqn_tpg_lock);
3282 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3283 
3284 			spin_lock(&tpg->tpg_state_lock);
3285 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3286 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3287 				spin_unlock(&tpg->tpg_state_lock);
3288 				continue;
3289 			}
3290 			spin_unlock(&tpg->tpg_state_lock);
3291 
3292 			spin_lock(&tpg->tpg_np_lock);
3293 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3294 						tpg_np_list) {
3295 				struct iscsi_np *np = tpg_np->tpg_np;
3296 				bool inaddr_any = iscsit_check_inaddr_any(np);
3297 
3298 				len = sprintf(buf, "TargetAddress="
3299 					"%s%s%s:%hu,%hu",
3300 					(np->np_sockaddr.ss_family == AF_INET6) ?
3301 					"[" : "", (inaddr_any == false) ?
3302 						np->np_ip : conn->local_ip,
3303 					(np->np_sockaddr.ss_family == AF_INET6) ?
3304 					"]" : "", (inaddr_any == false) ?
3305 						np->np_port : conn->local_port,
3306 					tpg->tpgt);
3307 				len += 1;
3308 
3309 				if ((len + payload_len) > buffer_len) {
3310 					spin_unlock(&tpg->tpg_np_lock);
3311 					spin_unlock(&tiqn->tiqn_tpg_lock);
3312 					end_of_buf = 1;
3313 					goto eob;
3314 				}
3315 				memcpy(payload + payload_len, buf, len);
3316 				payload_len += len;
3317 			}
3318 			spin_unlock(&tpg->tpg_np_lock);
3319 		}
3320 		spin_unlock(&tiqn->tiqn_tpg_lock);
3321 eob:
3322 		if (end_of_buf)
3323 			break;
3324 	}
3325 	spin_unlock(&tiqn_lock);
3326 
3327 	cmd->buf_ptr = payload;
3328 
3329 	return payload_len;
3330 }
3331 
3332 /*
3333  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3334  *	MaxRecvDataSegmentLength.
3335  */
3336 static int iscsit_send_text_rsp(
3337 	struct iscsi_cmd *cmd,
3338 	struct iscsi_conn *conn)
3339 {
3340 	struct iscsi_text_rsp *hdr;
3341 	struct kvec *iov;
3342 	u32 padding = 0, tx_size = 0;
3343 	int text_length, iov_count = 0;
3344 
3345 	text_length = iscsit_build_sendtargets_response(cmd);
3346 	if (text_length < 0)
3347 		return text_length;
3348 
3349 	padding = ((-text_length) & 3);
3350 	if (padding != 0) {
3351 		memset(cmd->buf_ptr + text_length, 0, padding);
3352 		pr_debug("Attaching %u additional bytes for"
3353 			" padding.\n", padding);
3354 	}
3355 
3356 	hdr			= (struct iscsi_text_rsp *) cmd->pdu;
3357 	memset(hdr, 0, ISCSI_HDR_LEN);
3358 	hdr->opcode		= ISCSI_OP_TEXT_RSP;
3359 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3360 	hton24(hdr->dlength, text_length);
3361 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3362 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
3363 	cmd->stat_sn		= conn->stat_sn++;
3364 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3365 
3366 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3367 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3368 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3369 
3370 	iov = &cmd->iov_misc[0];
3371 
3372 	iov[iov_count].iov_base = cmd->pdu;
3373 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3374 	iov[iov_count].iov_base	= cmd->buf_ptr;
3375 	iov[iov_count++].iov_len = text_length + padding;
3376 
3377 	tx_size += (ISCSI_HDR_LEN + text_length + padding);
3378 
3379 	if (conn->conn_ops->HeaderDigest) {
3380 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3381 
3382 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3383 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3384 				0, NULL, (u8 *)header_digest);
3385 
3386 		iov[0].iov_len += ISCSI_CRC_LEN;
3387 		tx_size += ISCSI_CRC_LEN;
3388 		pr_debug("Attaching CRC32 HeaderDigest for"
3389 			" Text Response PDU 0x%08x\n", *header_digest);
3390 	}
3391 
3392 	if (conn->conn_ops->DataDigest) {
3393 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3394 				cmd->buf_ptr, (text_length + padding),
3395 				0, NULL, (u8 *)&cmd->data_crc);
3396 
3397 		iov[iov_count].iov_base	= &cmd->data_crc;
3398 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3399 		tx_size	+= ISCSI_CRC_LEN;
3400 
3401 		pr_debug("Attaching DataDigest for %u bytes of text"
3402 			" data, CRC 0x%08x\n", (text_length + padding),
3403 			cmd->data_crc);
3404 	}
3405 
3406 	cmd->iov_misc_count = iov_count;
3407 	cmd->tx_size = tx_size;
3408 
3409 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3410 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3411 			text_length, conn->cid);
3412 	return 0;
3413 }
3414 
3415 static int iscsit_send_reject(
3416 	struct iscsi_cmd *cmd,
3417 	struct iscsi_conn *conn)
3418 {
3419 	u32 iov_count = 0, tx_size = 0;
3420 	struct iscsi_reject *hdr;
3421 	struct kvec *iov;
3422 
3423 	hdr			= (struct iscsi_reject *) cmd->pdu;
3424 	hdr->opcode		= ISCSI_OP_REJECT;
3425 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3426 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3427 	cmd->stat_sn		= conn->stat_sn++;
3428 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3429 	hdr->exp_cmdsn	= cpu_to_be32(conn->sess->exp_cmd_sn);
3430 	hdr->max_cmdsn	= cpu_to_be32(conn->sess->max_cmd_sn);
3431 
3432 	iov = &cmd->iov_misc[0];
3433 
3434 	iov[iov_count].iov_base = cmd->pdu;
3435 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3436 	iov[iov_count].iov_base = cmd->buf_ptr;
3437 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3438 
3439 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3440 
3441 	if (conn->conn_ops->HeaderDigest) {
3442 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3443 
3444 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3445 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3446 				0, NULL, (u8 *)header_digest);
3447 
3448 		iov[0].iov_len += ISCSI_CRC_LEN;
3449 		tx_size += ISCSI_CRC_LEN;
3450 		pr_debug("Attaching CRC32 HeaderDigest for"
3451 			" REJECT PDU 0x%08x\n", *header_digest);
3452 	}
3453 
3454 	if (conn->conn_ops->DataDigest) {
3455 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3456 				(unsigned char *)cmd->buf_ptr, ISCSI_HDR_LEN,
3457 				0, NULL, (u8 *)&cmd->data_crc);
3458 
3459 		iov[iov_count].iov_base = &cmd->data_crc;
3460 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3461 		tx_size += ISCSI_CRC_LEN;
3462 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3463 				" PDU 0x%08x\n", cmd->data_crc);
3464 	}
3465 
3466 	cmd->iov_misc_count = iov_count;
3467 	cmd->tx_size = tx_size;
3468 
3469 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3470 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3471 
3472 	return 0;
3473 }
3474 
3475 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3476 {
3477 	struct iscsi_thread_set *ts = conn->thread_set;
3478 	int ord, cpu;
3479 	/*
3480 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3481 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3482 	 *
3483 	 * Here we use thread_id to determine which CPU that this
3484 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3485 	 * execute upon.
3486 	 */
3487 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3488 	for_each_online_cpu(cpu) {
3489 		if (ord-- == 0) {
3490 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3491 			return;
3492 		}
3493 	}
3494 	/*
3495 	 * This should never be reached..
3496 	 */
3497 	dump_stack();
3498 	cpumask_setall(conn->conn_cpumask);
3499 }
3500 
3501 static inline void iscsit_thread_check_cpumask(
3502 	struct iscsi_conn *conn,
3503 	struct task_struct *p,
3504 	int mode)
3505 {
3506 	char buf[128];
3507 	/*
3508 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3509 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3510 	 */
3511 	if (mode == 1) {
3512 		if (!conn->conn_tx_reset_cpumask)
3513 			return;
3514 		conn->conn_tx_reset_cpumask = 0;
3515 	} else {
3516 		if (!conn->conn_rx_reset_cpumask)
3517 			return;
3518 		conn->conn_rx_reset_cpumask = 0;
3519 	}
3520 	/*
3521 	 * Update the CPU mask for this single kthread so that
3522 	 * both TX and RX kthreads are scheduled to run on the
3523 	 * same CPU.
3524 	 */
3525 	memset(buf, 0, 128);
3526 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3527 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3528 }
3529 
3530 static int handle_immediate_queue(struct iscsi_conn *conn)
3531 {
3532 	struct iscsi_queue_req *qr;
3533 	struct iscsi_cmd *cmd;
3534 	u8 state;
3535 	int ret;
3536 
3537 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3538 		atomic_set(&conn->check_immediate_queue, 0);
3539 		cmd = qr->cmd;
3540 		state = qr->state;
3541 		kmem_cache_free(lio_qr_cache, qr);
3542 
3543 		switch (state) {
3544 		case ISTATE_SEND_R2T:
3545 			ret = iscsit_send_r2t(cmd, conn);
3546 			if (ret < 0)
3547 				goto err;
3548 			break;
3549 		case ISTATE_REMOVE:
3550 			if (cmd->data_direction == DMA_TO_DEVICE)
3551 				iscsit_stop_dataout_timer(cmd);
3552 
3553 			spin_lock_bh(&conn->cmd_lock);
3554 			list_del(&cmd->i_conn_node);
3555 			spin_unlock_bh(&conn->cmd_lock);
3556 
3557 			iscsit_free_cmd(cmd);
3558 			continue;
3559 		case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3560 			iscsit_mod_nopin_response_timer(conn);
3561 			ret = iscsit_send_unsolicited_nopin(cmd,
3562 							    conn, 1);
3563 			if (ret < 0)
3564 				goto err;
3565 			break;
3566 		case ISTATE_SEND_NOPIN_NO_RESPONSE:
3567 			ret = iscsit_send_unsolicited_nopin(cmd,
3568 							    conn, 0);
3569 			if (ret < 0)
3570 				goto err;
3571 			break;
3572 		default:
3573 			pr_err("Unknown Opcode: 0x%02x ITT:"
3574 			       " 0x%08x, i_state: %d on CID: %hu\n",
3575 			       cmd->iscsi_opcode, cmd->init_task_tag, state,
3576 			       conn->cid);
3577 			goto err;
3578 		}
3579 	}
3580 
3581 	return 0;
3582 
3583 err:
3584 	return -1;
3585 }
3586 
3587 static int handle_response_queue(struct iscsi_conn *conn)
3588 {
3589 	struct iscsi_queue_req *qr;
3590 	struct iscsi_cmd *cmd;
3591 	u8 state;
3592 	int ret;
3593 
3594 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3595 		cmd = qr->cmd;
3596 		state = qr->state;
3597 		kmem_cache_free(lio_qr_cache, qr);
3598 
3599 check_rsp_state:
3600 		switch (state) {
3601 		case ISTATE_SEND_DATAIN:
3602 			ret = iscsit_send_data_in(cmd, conn);
3603 			if (ret < 0)
3604 				goto err;
3605 			else if (!ret)
3606 				/* more drs */
3607 				goto check_rsp_state;
3608 			else if (ret == 1) {
3609 				/* all done */
3610 				spin_lock_bh(&cmd->istate_lock);
3611 				cmd->i_state = ISTATE_SENT_STATUS;
3612 				spin_unlock_bh(&cmd->istate_lock);
3613 				continue;
3614 			} else if (ret == 2) {
3615 				/* Still must send status,
3616 				   SCF_TRANSPORT_TASK_SENSE was set */
3617 				spin_lock_bh(&cmd->istate_lock);
3618 				cmd->i_state = ISTATE_SEND_STATUS;
3619 				spin_unlock_bh(&cmd->istate_lock);
3620 				state = ISTATE_SEND_STATUS;
3621 				goto check_rsp_state;
3622 			}
3623 
3624 			break;
3625 		case ISTATE_SEND_STATUS:
3626 		case ISTATE_SEND_STATUS_RECOVERY:
3627 			ret = iscsit_send_status(cmd, conn);
3628 			break;
3629 		case ISTATE_SEND_LOGOUTRSP:
3630 			ret = iscsit_send_logout_response(cmd, conn);
3631 			break;
3632 		case ISTATE_SEND_ASYNCMSG:
3633 			ret = iscsit_send_conn_drop_async_message(
3634 				cmd, conn);
3635 			break;
3636 		case ISTATE_SEND_NOPIN:
3637 			ret = iscsit_send_nopin_response(cmd, conn);
3638 			break;
3639 		case ISTATE_SEND_REJECT:
3640 			ret = iscsit_send_reject(cmd, conn);
3641 			break;
3642 		case ISTATE_SEND_TASKMGTRSP:
3643 			ret = iscsit_send_task_mgt_rsp(cmd, conn);
3644 			if (ret != 0)
3645 				break;
3646 			ret = iscsit_tmr_post_handler(cmd, conn);
3647 			if (ret != 0)
3648 				iscsit_fall_back_to_erl0(conn->sess);
3649 			break;
3650 		case ISTATE_SEND_TEXTRSP:
3651 			ret = iscsit_send_text_rsp(cmd, conn);
3652 			break;
3653 		default:
3654 			pr_err("Unknown Opcode: 0x%02x ITT:"
3655 			       " 0x%08x, i_state: %d on CID: %hu\n",
3656 			       cmd->iscsi_opcode, cmd->init_task_tag,
3657 			       state, conn->cid);
3658 			goto err;
3659 		}
3660 		if (ret < 0)
3661 			goto err;
3662 
3663 		if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3664 			iscsit_tx_thread_wait_for_tcp(conn);
3665 			iscsit_unmap_iovec(cmd);
3666 			goto err;
3667 		}
3668 		iscsit_unmap_iovec(cmd);
3669 
3670 		switch (state) {
3671 		case ISTATE_SEND_LOGOUTRSP:
3672 			if (!iscsit_logout_post_handler(cmd, conn))
3673 				goto restart;
3674 			/* fall through */
3675 		case ISTATE_SEND_STATUS:
3676 		case ISTATE_SEND_ASYNCMSG:
3677 		case ISTATE_SEND_NOPIN:
3678 		case ISTATE_SEND_STATUS_RECOVERY:
3679 		case ISTATE_SEND_TEXTRSP:
3680 		case ISTATE_SEND_TASKMGTRSP:
3681 			spin_lock_bh(&cmd->istate_lock);
3682 			cmd->i_state = ISTATE_SENT_STATUS;
3683 			spin_unlock_bh(&cmd->istate_lock);
3684 			break;
3685 		case ISTATE_SEND_REJECT:
3686 			if (cmd->cmd_flags & ICF_REJECT_FAIL_CONN) {
3687 				cmd->cmd_flags &= ~ICF_REJECT_FAIL_CONN;
3688 				complete(&cmd->reject_comp);
3689 				goto err;
3690 			}
3691 			complete(&cmd->reject_comp);
3692 			break;
3693 		default:
3694 			pr_err("Unknown Opcode: 0x%02x ITT:"
3695 			       " 0x%08x, i_state: %d on CID: %hu\n",
3696 			       cmd->iscsi_opcode, cmd->init_task_tag,
3697 			       cmd->i_state, conn->cid);
3698 			goto err;
3699 		}
3700 
3701 		if (atomic_read(&conn->check_immediate_queue))
3702 			break;
3703 	}
3704 
3705 	return 0;
3706 
3707 err:
3708 	return -1;
3709 restart:
3710 	return -EAGAIN;
3711 }
3712 
3713 int iscsi_target_tx_thread(void *arg)
3714 {
3715 	int ret = 0;
3716 	struct iscsi_conn *conn;
3717 	struct iscsi_thread_set *ts = arg;
3718 	/*
3719 	 * Allow ourselves to be interrupted by SIGINT so that a
3720 	 * connection recovery / failure event can be triggered externally.
3721 	 */
3722 	allow_signal(SIGINT);
3723 
3724 restart:
3725 	conn = iscsi_tx_thread_pre_handler(ts);
3726 	if (!conn)
3727 		goto out;
3728 
3729 	ret = 0;
3730 
3731 	while (!kthread_should_stop()) {
3732 		/*
3733 		 * Ensure that both TX and RX per connection kthreads
3734 		 * are scheduled to run on the same CPU.
3735 		 */
3736 		iscsit_thread_check_cpumask(conn, current, 1);
3737 
3738 		schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
3739 
3740 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3741 		     signal_pending(current))
3742 			goto transport_err;
3743 
3744 		ret = handle_immediate_queue(conn);
3745 		if (ret < 0)
3746 			goto transport_err;
3747 
3748 		ret = handle_response_queue(conn);
3749 		if (ret == -EAGAIN)
3750 			goto restart;
3751 		else if (ret < 0)
3752 			goto transport_err;
3753 	}
3754 
3755 transport_err:
3756 	iscsit_take_action_for_connection_exit(conn);
3757 	goto restart;
3758 out:
3759 	return 0;
3760 }
3761 
3762 int iscsi_target_rx_thread(void *arg)
3763 {
3764 	int ret;
3765 	u8 buffer[ISCSI_HDR_LEN], opcode;
3766 	u32 checksum = 0, digest = 0;
3767 	struct iscsi_conn *conn = NULL;
3768 	struct iscsi_thread_set *ts = arg;
3769 	struct kvec iov;
3770 	/*
3771 	 * Allow ourselves to be interrupted by SIGINT so that a
3772 	 * connection recovery / failure event can be triggered externally.
3773 	 */
3774 	allow_signal(SIGINT);
3775 
3776 restart:
3777 	conn = iscsi_rx_thread_pre_handler(ts);
3778 	if (!conn)
3779 		goto out;
3780 
3781 	while (!kthread_should_stop()) {
3782 		/*
3783 		 * Ensure that both TX and RX per connection kthreads
3784 		 * are scheduled to run on the same CPU.
3785 		 */
3786 		iscsit_thread_check_cpumask(conn, current, 0);
3787 
3788 		memset(buffer, 0, ISCSI_HDR_LEN);
3789 		memset(&iov, 0, sizeof(struct kvec));
3790 
3791 		iov.iov_base	= buffer;
3792 		iov.iov_len	= ISCSI_HDR_LEN;
3793 
3794 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
3795 		if (ret != ISCSI_HDR_LEN) {
3796 			iscsit_rx_thread_wait_for_tcp(conn);
3797 			goto transport_err;
3798 		}
3799 
3800 		/*
3801 		 * Set conn->bad_hdr for use with REJECT PDUs.
3802 		 */
3803 		memcpy(&conn->bad_hdr, &buffer, ISCSI_HDR_LEN);
3804 
3805 		if (conn->conn_ops->HeaderDigest) {
3806 			iov.iov_base	= &digest;
3807 			iov.iov_len	= ISCSI_CRC_LEN;
3808 
3809 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
3810 			if (ret != ISCSI_CRC_LEN) {
3811 				iscsit_rx_thread_wait_for_tcp(conn);
3812 				goto transport_err;
3813 			}
3814 
3815 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
3816 					buffer, ISCSI_HDR_LEN,
3817 					0, NULL, (u8 *)&checksum);
3818 
3819 			if (digest != checksum) {
3820 				pr_err("HeaderDigest CRC32C failed,"
3821 					" received 0x%08x, computed 0x%08x\n",
3822 					digest, checksum);
3823 				/*
3824 				 * Set the PDU to 0xff so it will intentionally
3825 				 * hit default in the switch below.
3826 				 */
3827 				memset(buffer, 0xff, ISCSI_HDR_LEN);
3828 				spin_lock_bh(&conn->sess->session_stats_lock);
3829 				conn->sess->conn_digest_errors++;
3830 				spin_unlock_bh(&conn->sess->session_stats_lock);
3831 			} else {
3832 				pr_debug("Got HeaderDigest CRC32C"
3833 						" 0x%08x\n", checksum);
3834 			}
3835 		}
3836 
3837 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
3838 			goto transport_err;
3839 
3840 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
3841 
3842 		if (conn->sess->sess_ops->SessionType &&
3843 		   ((!(opcode & ISCSI_OP_TEXT)) ||
3844 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
3845 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
3846 			" while in Discovery Session, rejecting.\n", opcode);
3847 			iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
3848 					buffer, conn);
3849 			goto transport_err;
3850 		}
3851 
3852 		switch (opcode) {
3853 		case ISCSI_OP_SCSI_CMD:
3854 			if (iscsit_handle_scsi_cmd(conn, buffer) < 0)
3855 				goto transport_err;
3856 			break;
3857 		case ISCSI_OP_SCSI_DATA_OUT:
3858 			if (iscsit_handle_data_out(conn, buffer) < 0)
3859 				goto transport_err;
3860 			break;
3861 		case ISCSI_OP_NOOP_OUT:
3862 			if (iscsit_handle_nop_out(conn, buffer) < 0)
3863 				goto transport_err;
3864 			break;
3865 		case ISCSI_OP_SCSI_TMFUNC:
3866 			if (iscsit_handle_task_mgt_cmd(conn, buffer) < 0)
3867 				goto transport_err;
3868 			break;
3869 		case ISCSI_OP_TEXT:
3870 			if (iscsit_handle_text_cmd(conn, buffer) < 0)
3871 				goto transport_err;
3872 			break;
3873 		case ISCSI_OP_LOGOUT:
3874 			ret = iscsit_handle_logout_cmd(conn, buffer);
3875 			if (ret > 0) {
3876 				wait_for_completion_timeout(&conn->conn_logout_comp,
3877 						SECONDS_FOR_LOGOUT_COMP * HZ);
3878 				goto transport_err;
3879 			} else if (ret < 0)
3880 				goto transport_err;
3881 			break;
3882 		case ISCSI_OP_SNACK:
3883 			if (iscsit_handle_snack(conn, buffer) < 0)
3884 				goto transport_err;
3885 			break;
3886 		default:
3887 			pr_err("Got unknown iSCSI OpCode: 0x%02x\n",
3888 					opcode);
3889 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3890 				pr_err("Cannot recover from unknown"
3891 				" opcode while ERL=0, closing iSCSI connection"
3892 				".\n");
3893 				goto transport_err;
3894 			}
3895 			if (!conn->conn_ops->OFMarker) {
3896 				pr_err("Unable to recover from unknown"
3897 				" opcode while OFMarker=No, closing iSCSI"
3898 					" connection.\n");
3899 				goto transport_err;
3900 			}
3901 			if (iscsit_recover_from_unknown_opcode(conn) < 0) {
3902 				pr_err("Unable to recover from unknown"
3903 					" opcode, closing iSCSI connection.\n");
3904 				goto transport_err;
3905 			}
3906 			break;
3907 		}
3908 	}
3909 
3910 transport_err:
3911 	if (!signal_pending(current))
3912 		atomic_set(&conn->transport_failed, 1);
3913 	iscsit_take_action_for_connection_exit(conn);
3914 	goto restart;
3915 out:
3916 	return 0;
3917 }
3918 
3919 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
3920 {
3921 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
3922 	struct iscsi_session *sess = conn->sess;
3923 	/*
3924 	 * We expect this function to only ever be called from either RX or TX
3925 	 * thread context via iscsit_close_connection() once the other context
3926 	 * has been reset -> returned sleeping pre-handler state.
3927 	 */
3928 	spin_lock_bh(&conn->cmd_lock);
3929 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
3930 
3931 		list_del(&cmd->i_conn_node);
3932 		spin_unlock_bh(&conn->cmd_lock);
3933 
3934 		iscsit_increment_maxcmdsn(cmd, sess);
3935 
3936 		iscsit_free_cmd(cmd);
3937 
3938 		spin_lock_bh(&conn->cmd_lock);
3939 	}
3940 	spin_unlock_bh(&conn->cmd_lock);
3941 }
3942 
3943 static void iscsit_stop_timers_for_cmds(
3944 	struct iscsi_conn *conn)
3945 {
3946 	struct iscsi_cmd *cmd;
3947 
3948 	spin_lock_bh(&conn->cmd_lock);
3949 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
3950 		if (cmd->data_direction == DMA_TO_DEVICE)
3951 			iscsit_stop_dataout_timer(cmd);
3952 	}
3953 	spin_unlock_bh(&conn->cmd_lock);
3954 }
3955 
3956 int iscsit_close_connection(
3957 	struct iscsi_conn *conn)
3958 {
3959 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
3960 	struct iscsi_session	*sess = conn->sess;
3961 
3962 	pr_debug("Closing iSCSI connection CID %hu on SID:"
3963 		" %u\n", conn->cid, sess->sid);
3964 	/*
3965 	 * Always up conn_logout_comp just in case the RX Thread is sleeping
3966 	 * and the logout response never got sent because the connection
3967 	 * failed.
3968 	 */
3969 	complete(&conn->conn_logout_comp);
3970 
3971 	iscsi_release_thread_set(conn);
3972 
3973 	iscsit_stop_timers_for_cmds(conn);
3974 	iscsit_stop_nopin_response_timer(conn);
3975 	iscsit_stop_nopin_timer(conn);
3976 	iscsit_free_queue_reqs_for_conn(conn);
3977 
3978 	/*
3979 	 * During Connection recovery drop unacknowledged out of order
3980 	 * commands for this connection, and prepare the other commands
3981 	 * for realligence.
3982 	 *
3983 	 * During normal operation clear the out of order commands (but
3984 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
3985 	 * struct iscsi_cmds.
3986 	 */
3987 	if (atomic_read(&conn->connection_recovery)) {
3988 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
3989 		iscsit_prepare_cmds_for_realligance(conn);
3990 	} else {
3991 		iscsit_clear_ooo_cmdsns_for_conn(conn);
3992 		iscsit_release_commands_from_conn(conn);
3993 	}
3994 
3995 	/*
3996 	 * Handle decrementing session or connection usage count if
3997 	 * a logout response was not able to be sent because the
3998 	 * connection failed.  Fall back to Session Recovery here.
3999 	 */
4000 	if (atomic_read(&conn->conn_logout_remove)) {
4001 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4002 			iscsit_dec_conn_usage_count(conn);
4003 			iscsit_dec_session_usage_count(sess);
4004 		}
4005 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4006 			iscsit_dec_conn_usage_count(conn);
4007 
4008 		atomic_set(&conn->conn_logout_remove, 0);
4009 		atomic_set(&sess->session_reinstatement, 0);
4010 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4011 	}
4012 
4013 	spin_lock_bh(&sess->conn_lock);
4014 	list_del(&conn->conn_list);
4015 
4016 	/*
4017 	 * Attempt to let the Initiator know this connection failed by
4018 	 * sending an Connection Dropped Async Message on another
4019 	 * active connection.
4020 	 */
4021 	if (atomic_read(&conn->connection_recovery))
4022 		iscsit_build_conn_drop_async_message(conn);
4023 
4024 	spin_unlock_bh(&sess->conn_lock);
4025 
4026 	/*
4027 	 * If connection reinstatement is being performed on this connection,
4028 	 * up the connection reinstatement semaphore that is being blocked on
4029 	 * in iscsit_cause_connection_reinstatement().
4030 	 */
4031 	spin_lock_bh(&conn->state_lock);
4032 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4033 		spin_unlock_bh(&conn->state_lock);
4034 		complete(&conn->conn_wait_comp);
4035 		wait_for_completion(&conn->conn_post_wait_comp);
4036 		spin_lock_bh(&conn->state_lock);
4037 	}
4038 
4039 	/*
4040 	 * If connection reinstatement is being performed on this connection
4041 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4042 	 * connection wait rcfr semaphore that is being blocked on
4043 	 * an iscsit_connection_reinstatement_rcfr().
4044 	 */
4045 	if (atomic_read(&conn->connection_wait_rcfr)) {
4046 		spin_unlock_bh(&conn->state_lock);
4047 		complete(&conn->conn_wait_rcfr_comp);
4048 		wait_for_completion(&conn->conn_post_wait_comp);
4049 		spin_lock_bh(&conn->state_lock);
4050 	}
4051 	atomic_set(&conn->connection_reinstatement, 1);
4052 	spin_unlock_bh(&conn->state_lock);
4053 
4054 	/*
4055 	 * If any other processes are accessing this connection pointer we
4056 	 * must wait until they have completed.
4057 	 */
4058 	iscsit_check_conn_usage_count(conn);
4059 
4060 	if (conn->conn_rx_hash.tfm)
4061 		crypto_free_hash(conn->conn_rx_hash.tfm);
4062 	if (conn->conn_tx_hash.tfm)
4063 		crypto_free_hash(conn->conn_tx_hash.tfm);
4064 
4065 	if (conn->conn_cpumask)
4066 		free_cpumask_var(conn->conn_cpumask);
4067 
4068 	kfree(conn->conn_ops);
4069 	conn->conn_ops = NULL;
4070 
4071 	if (conn->sock)
4072 		sock_release(conn->sock);
4073 	conn->thread_set = NULL;
4074 
4075 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4076 	conn->conn_state = TARG_CONN_STATE_FREE;
4077 	kfree(conn);
4078 
4079 	spin_lock_bh(&sess->conn_lock);
4080 	atomic_dec(&sess->nconn);
4081 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4082 		" %s\n", atomic_read(&sess->nconn),
4083 		sess->sess_ops->InitiatorName);
4084 	/*
4085 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4086 	 * Session that they all fail.
4087 	 */
4088 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4089 	     !atomic_read(&sess->session_logout))
4090 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4091 
4092 	/*
4093 	 * If this was not the last connection in the session, and we are
4094 	 * performing session reinstatement or falling back to ERL=0, call
4095 	 * iscsit_stop_session() without sleeping to shutdown the other
4096 	 * active connections.
4097 	 */
4098 	if (atomic_read(&sess->nconn)) {
4099 		if (!atomic_read(&sess->session_reinstatement) &&
4100 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4101 			spin_unlock_bh(&sess->conn_lock);
4102 			return 0;
4103 		}
4104 		if (!atomic_read(&sess->session_stop_active)) {
4105 			atomic_set(&sess->session_stop_active, 1);
4106 			spin_unlock_bh(&sess->conn_lock);
4107 			iscsit_stop_session(sess, 0, 0);
4108 			return 0;
4109 		}
4110 		spin_unlock_bh(&sess->conn_lock);
4111 		return 0;
4112 	}
4113 
4114 	/*
4115 	 * If this was the last connection in the session and one of the
4116 	 * following is occurring:
4117 	 *
4118 	 * Session Reinstatement is not being performed, and are falling back
4119 	 * to ERL=0 call iscsit_close_session().
4120 	 *
4121 	 * Session Logout was requested.  iscsit_close_session() will be called
4122 	 * elsewhere.
4123 	 *
4124 	 * Session Continuation is not being performed, start the Time2Retain
4125 	 * handler and check if sleep_on_sess_wait_sem is active.
4126 	 */
4127 	if (!atomic_read(&sess->session_reinstatement) &&
4128 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4129 		spin_unlock_bh(&sess->conn_lock);
4130 		target_put_session(sess->se_sess);
4131 
4132 		return 0;
4133 	} else if (atomic_read(&sess->session_logout)) {
4134 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4135 		sess->session_state = TARG_SESS_STATE_FREE;
4136 		spin_unlock_bh(&sess->conn_lock);
4137 
4138 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4139 			complete(&sess->session_wait_comp);
4140 
4141 		return 0;
4142 	} else {
4143 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4144 		sess->session_state = TARG_SESS_STATE_FAILED;
4145 
4146 		if (!atomic_read(&sess->session_continuation)) {
4147 			spin_unlock_bh(&sess->conn_lock);
4148 			iscsit_start_time2retain_handler(sess);
4149 		} else
4150 			spin_unlock_bh(&sess->conn_lock);
4151 
4152 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4153 			complete(&sess->session_wait_comp);
4154 
4155 		return 0;
4156 	}
4157 	spin_unlock_bh(&sess->conn_lock);
4158 
4159 	return 0;
4160 }
4161 
4162 int iscsit_close_session(struct iscsi_session *sess)
4163 {
4164 	struct iscsi_portal_group *tpg = ISCSI_TPG_S(sess);
4165 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4166 
4167 	if (atomic_read(&sess->nconn)) {
4168 		pr_err("%d connection(s) still exist for iSCSI session"
4169 			" to %s\n", atomic_read(&sess->nconn),
4170 			sess->sess_ops->InitiatorName);
4171 		BUG();
4172 	}
4173 
4174 	spin_lock_bh(&se_tpg->session_lock);
4175 	atomic_set(&sess->session_logout, 1);
4176 	atomic_set(&sess->session_reinstatement, 1);
4177 	iscsit_stop_time2retain_timer(sess);
4178 	spin_unlock_bh(&se_tpg->session_lock);
4179 
4180 	/*
4181 	 * transport_deregister_session_configfs() will clear the
4182 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4183 	 * can be setting it again with __transport_register_session() in
4184 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4185 	 * completes in iscsi_np context.
4186 	 */
4187 	transport_deregister_session_configfs(sess->se_sess);
4188 
4189 	/*
4190 	 * If any other processes are accessing this session pointer we must
4191 	 * wait until they have completed.  If we are in an interrupt (the
4192 	 * time2retain handler) and contain and active session usage count we
4193 	 * restart the timer and exit.
4194 	 */
4195 	if (!in_interrupt()) {
4196 		if (iscsit_check_session_usage_count(sess) == 1)
4197 			iscsit_stop_session(sess, 1, 1);
4198 	} else {
4199 		if (iscsit_check_session_usage_count(sess) == 2) {
4200 			atomic_set(&sess->session_logout, 0);
4201 			iscsit_start_time2retain_handler(sess);
4202 			return 0;
4203 		}
4204 	}
4205 
4206 	transport_deregister_session(sess->se_sess);
4207 
4208 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4209 		iscsit_free_connection_recovery_entires(sess);
4210 
4211 	iscsit_free_all_ooo_cmdsns(sess);
4212 
4213 	spin_lock_bh(&se_tpg->session_lock);
4214 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4215 	sess->session_state = TARG_SESS_STATE_FREE;
4216 	pr_debug("Released iSCSI session from node: %s\n",
4217 			sess->sess_ops->InitiatorName);
4218 	tpg->nsessions--;
4219 	if (tpg->tpg_tiqn)
4220 		tpg->tpg_tiqn->tiqn_nsessions--;
4221 
4222 	pr_debug("Decremented number of active iSCSI Sessions on"
4223 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4224 
4225 	spin_lock(&sess_idr_lock);
4226 	idr_remove(&sess_idr, sess->session_index);
4227 	spin_unlock(&sess_idr_lock);
4228 
4229 	kfree(sess->sess_ops);
4230 	sess->sess_ops = NULL;
4231 	spin_unlock_bh(&se_tpg->session_lock);
4232 
4233 	kfree(sess);
4234 	return 0;
4235 }
4236 
4237 static void iscsit_logout_post_handler_closesession(
4238 	struct iscsi_conn *conn)
4239 {
4240 	struct iscsi_session *sess = conn->sess;
4241 
4242 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4243 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4244 
4245 	atomic_set(&conn->conn_logout_remove, 0);
4246 	complete(&conn->conn_logout_comp);
4247 
4248 	iscsit_dec_conn_usage_count(conn);
4249 	iscsit_stop_session(sess, 1, 1);
4250 	iscsit_dec_session_usage_count(sess);
4251 	target_put_session(sess->se_sess);
4252 }
4253 
4254 static void iscsit_logout_post_handler_samecid(
4255 	struct iscsi_conn *conn)
4256 {
4257 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4258 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4259 
4260 	atomic_set(&conn->conn_logout_remove, 0);
4261 	complete(&conn->conn_logout_comp);
4262 
4263 	iscsit_cause_connection_reinstatement(conn, 1);
4264 	iscsit_dec_conn_usage_count(conn);
4265 }
4266 
4267 static void iscsit_logout_post_handler_diffcid(
4268 	struct iscsi_conn *conn,
4269 	u16 cid)
4270 {
4271 	struct iscsi_conn *l_conn;
4272 	struct iscsi_session *sess = conn->sess;
4273 
4274 	if (!sess)
4275 		return;
4276 
4277 	spin_lock_bh(&sess->conn_lock);
4278 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4279 		if (l_conn->cid == cid) {
4280 			iscsit_inc_conn_usage_count(l_conn);
4281 			break;
4282 		}
4283 	}
4284 	spin_unlock_bh(&sess->conn_lock);
4285 
4286 	if (!l_conn)
4287 		return;
4288 
4289 	if (l_conn->sock)
4290 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4291 
4292 	spin_lock_bh(&l_conn->state_lock);
4293 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4294 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4295 	spin_unlock_bh(&l_conn->state_lock);
4296 
4297 	iscsit_cause_connection_reinstatement(l_conn, 1);
4298 	iscsit_dec_conn_usage_count(l_conn);
4299 }
4300 
4301 /*
4302  *	Return of 0 causes the TX thread to restart.
4303  */
4304 static int iscsit_logout_post_handler(
4305 	struct iscsi_cmd *cmd,
4306 	struct iscsi_conn *conn)
4307 {
4308 	int ret = 0;
4309 
4310 	switch (cmd->logout_reason) {
4311 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4312 		switch (cmd->logout_response) {
4313 		case ISCSI_LOGOUT_SUCCESS:
4314 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4315 		default:
4316 			iscsit_logout_post_handler_closesession(conn);
4317 			break;
4318 		}
4319 		ret = 0;
4320 		break;
4321 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4322 		if (conn->cid == cmd->logout_cid) {
4323 			switch (cmd->logout_response) {
4324 			case ISCSI_LOGOUT_SUCCESS:
4325 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4326 			default:
4327 				iscsit_logout_post_handler_samecid(conn);
4328 				break;
4329 			}
4330 			ret = 0;
4331 		} else {
4332 			switch (cmd->logout_response) {
4333 			case ISCSI_LOGOUT_SUCCESS:
4334 				iscsit_logout_post_handler_diffcid(conn,
4335 					cmd->logout_cid);
4336 				break;
4337 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4338 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4339 			default:
4340 				break;
4341 			}
4342 			ret = 1;
4343 		}
4344 		break;
4345 	case ISCSI_LOGOUT_REASON_RECOVERY:
4346 		switch (cmd->logout_response) {
4347 		case ISCSI_LOGOUT_SUCCESS:
4348 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4349 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4350 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4351 		default:
4352 			break;
4353 		}
4354 		ret = 1;
4355 		break;
4356 	default:
4357 		break;
4358 
4359 	}
4360 	return ret;
4361 }
4362 
4363 void iscsit_fail_session(struct iscsi_session *sess)
4364 {
4365 	struct iscsi_conn *conn;
4366 
4367 	spin_lock_bh(&sess->conn_lock);
4368 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4369 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4370 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4371 	}
4372 	spin_unlock_bh(&sess->conn_lock);
4373 
4374 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4375 	sess->session_state = TARG_SESS_STATE_FAILED;
4376 }
4377 
4378 int iscsit_free_session(struct iscsi_session *sess)
4379 {
4380 	u16 conn_count = atomic_read(&sess->nconn);
4381 	struct iscsi_conn *conn, *conn_tmp = NULL;
4382 	int is_last;
4383 
4384 	spin_lock_bh(&sess->conn_lock);
4385 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4386 
4387 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4388 			conn_list) {
4389 		if (conn_count == 0)
4390 			break;
4391 
4392 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4393 			is_last = 1;
4394 		} else {
4395 			iscsit_inc_conn_usage_count(conn_tmp);
4396 			is_last = 0;
4397 		}
4398 		iscsit_inc_conn_usage_count(conn);
4399 
4400 		spin_unlock_bh(&sess->conn_lock);
4401 		iscsit_cause_connection_reinstatement(conn, 1);
4402 		spin_lock_bh(&sess->conn_lock);
4403 
4404 		iscsit_dec_conn_usage_count(conn);
4405 		if (is_last == 0)
4406 			iscsit_dec_conn_usage_count(conn_tmp);
4407 
4408 		conn_count--;
4409 	}
4410 
4411 	if (atomic_read(&sess->nconn)) {
4412 		spin_unlock_bh(&sess->conn_lock);
4413 		wait_for_completion(&sess->session_wait_comp);
4414 	} else
4415 		spin_unlock_bh(&sess->conn_lock);
4416 
4417 	target_put_session(sess->se_sess);
4418 	return 0;
4419 }
4420 
4421 void iscsit_stop_session(
4422 	struct iscsi_session *sess,
4423 	int session_sleep,
4424 	int connection_sleep)
4425 {
4426 	u16 conn_count = atomic_read(&sess->nconn);
4427 	struct iscsi_conn *conn, *conn_tmp = NULL;
4428 	int is_last;
4429 
4430 	spin_lock_bh(&sess->conn_lock);
4431 	if (session_sleep)
4432 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4433 
4434 	if (connection_sleep) {
4435 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4436 				conn_list) {
4437 			if (conn_count == 0)
4438 				break;
4439 
4440 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4441 				is_last = 1;
4442 			} else {
4443 				iscsit_inc_conn_usage_count(conn_tmp);
4444 				is_last = 0;
4445 			}
4446 			iscsit_inc_conn_usage_count(conn);
4447 
4448 			spin_unlock_bh(&sess->conn_lock);
4449 			iscsit_cause_connection_reinstatement(conn, 1);
4450 			spin_lock_bh(&sess->conn_lock);
4451 
4452 			iscsit_dec_conn_usage_count(conn);
4453 			if (is_last == 0)
4454 				iscsit_dec_conn_usage_count(conn_tmp);
4455 			conn_count--;
4456 		}
4457 	} else {
4458 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4459 			iscsit_cause_connection_reinstatement(conn, 0);
4460 	}
4461 
4462 	if (session_sleep && atomic_read(&sess->nconn)) {
4463 		spin_unlock_bh(&sess->conn_lock);
4464 		wait_for_completion(&sess->session_wait_comp);
4465 	} else
4466 		spin_unlock_bh(&sess->conn_lock);
4467 }
4468 
4469 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4470 {
4471 	struct iscsi_session *sess;
4472 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4473 	struct se_session *se_sess, *se_sess_tmp;
4474 	int session_count = 0;
4475 
4476 	spin_lock_bh(&se_tpg->session_lock);
4477 	if (tpg->nsessions && !force) {
4478 		spin_unlock_bh(&se_tpg->session_lock);
4479 		return -1;
4480 	}
4481 
4482 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4483 			sess_list) {
4484 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4485 
4486 		spin_lock(&sess->conn_lock);
4487 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4488 		    atomic_read(&sess->session_logout) ||
4489 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4490 			spin_unlock(&sess->conn_lock);
4491 			continue;
4492 		}
4493 		atomic_set(&sess->session_reinstatement, 1);
4494 		spin_unlock(&sess->conn_lock);
4495 		spin_unlock_bh(&se_tpg->session_lock);
4496 
4497 		iscsit_free_session(sess);
4498 		spin_lock_bh(&se_tpg->session_lock);
4499 
4500 		session_count++;
4501 	}
4502 	spin_unlock_bh(&se_tpg->session_lock);
4503 
4504 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4505 			" Group: %hu\n", session_count, tpg->tpgt);
4506 	return 0;
4507 }
4508 
4509 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4510 MODULE_VERSION("4.1.x");
4511 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4512 MODULE_LICENSE("GPL");
4513 
4514 module_init(iscsi_target_init_module);
4515 module_exit(iscsi_target_cleanup_module);
4516