xref: /linux/drivers/target/iscsi/iscsi_target.c (revision 5148fa52a12fa1b97c730b2fe321f2aad7ea041c)
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 		return 0;
434 
435 	/*
436 	 * Some network transports allocate their own struct sock->file,
437 	 * see  if we need to free any additional allocated resources.
438 	 */
439 	if (np->np_flags & NPF_SCTP_STRUCT_FILE) {
440 		kfree(np->np_socket->file);
441 		np->np_socket->file = NULL;
442 	}
443 
444 	sock_release(np->np_socket);
445 	return 0;
446 }
447 
448 int iscsit_del_np(struct iscsi_np *np)
449 {
450 	spin_lock_bh(&np->np_thread_lock);
451 	np->np_exports--;
452 	if (np->np_exports) {
453 		spin_unlock_bh(&np->np_thread_lock);
454 		return 0;
455 	}
456 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
457 	spin_unlock_bh(&np->np_thread_lock);
458 
459 	if (np->np_thread) {
460 		/*
461 		 * We need to send the signal to wakeup Linux/Net
462 		 * which may be sleeping in sock_accept()..
463 		 */
464 		send_sig(SIGINT, np->np_thread, 1);
465 		kthread_stop(np->np_thread);
466 	}
467 	iscsit_del_np_comm(np);
468 
469 	spin_lock_bh(&np_lock);
470 	list_del(&np->np_list);
471 	spin_unlock_bh(&np_lock);
472 
473 	pr_debug("CORE[0] - Removed Network Portal: %s:%hu on %s\n",
474 		np->np_ip, np->np_port, (np->np_network_transport == ISCSI_TCP) ?
475 		"TCP" : "SCTP");
476 
477 	kfree(np);
478 	return 0;
479 }
480 
481 static int __init iscsi_target_init_module(void)
482 {
483 	int ret = 0;
484 
485 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
486 
487 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
488 	if (!iscsit_global) {
489 		pr_err("Unable to allocate memory for iscsit_global\n");
490 		return -1;
491 	}
492 	mutex_init(&auth_id_lock);
493 	spin_lock_init(&sess_idr_lock);
494 	idr_init(&tiqn_idr);
495 	idr_init(&sess_idr);
496 
497 	ret = iscsi_target_register_configfs();
498 	if (ret < 0)
499 		goto out;
500 
501 	ret = iscsi_thread_set_init();
502 	if (ret < 0)
503 		goto configfs_out;
504 
505 	if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
506 			TARGET_THREAD_SET_COUNT) {
507 		pr_err("iscsi_allocate_thread_sets() returned"
508 			" unexpected value!\n");
509 		goto ts_out1;
510 	}
511 
512 	lio_cmd_cache = kmem_cache_create("lio_cmd_cache",
513 			sizeof(struct iscsi_cmd), __alignof__(struct iscsi_cmd),
514 			0, NULL);
515 	if (!lio_cmd_cache) {
516 		pr_err("Unable to kmem_cache_create() for"
517 				" lio_cmd_cache\n");
518 		goto ts_out2;
519 	}
520 
521 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
522 			sizeof(struct iscsi_queue_req),
523 			__alignof__(struct iscsi_queue_req), 0, NULL);
524 	if (!lio_qr_cache) {
525 		pr_err("nable to kmem_cache_create() for"
526 				" lio_qr_cache\n");
527 		goto cmd_out;
528 	}
529 
530 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
531 			sizeof(struct iscsi_datain_req),
532 			__alignof__(struct iscsi_datain_req), 0, NULL);
533 	if (!lio_dr_cache) {
534 		pr_err("Unable to kmem_cache_create() for"
535 				" lio_dr_cache\n");
536 		goto qr_out;
537 	}
538 
539 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
540 			sizeof(struct iscsi_ooo_cmdsn),
541 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
542 	if (!lio_ooo_cache) {
543 		pr_err("Unable to kmem_cache_create() for"
544 				" lio_ooo_cache\n");
545 		goto dr_out;
546 	}
547 
548 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
549 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
550 			0, NULL);
551 	if (!lio_r2t_cache) {
552 		pr_err("Unable to kmem_cache_create() for"
553 				" lio_r2t_cache\n");
554 		goto ooo_out;
555 	}
556 
557 	if (iscsit_load_discovery_tpg() < 0)
558 		goto r2t_out;
559 
560 	return ret;
561 r2t_out:
562 	kmem_cache_destroy(lio_r2t_cache);
563 ooo_out:
564 	kmem_cache_destroy(lio_ooo_cache);
565 dr_out:
566 	kmem_cache_destroy(lio_dr_cache);
567 qr_out:
568 	kmem_cache_destroy(lio_qr_cache);
569 cmd_out:
570 	kmem_cache_destroy(lio_cmd_cache);
571 ts_out2:
572 	iscsi_deallocate_thread_sets();
573 ts_out1:
574 	iscsi_thread_set_free();
575 configfs_out:
576 	iscsi_target_deregister_configfs();
577 out:
578 	kfree(iscsit_global);
579 	return -ENOMEM;
580 }
581 
582 static void __exit iscsi_target_cleanup_module(void)
583 {
584 	iscsi_deallocate_thread_sets();
585 	iscsi_thread_set_free();
586 	iscsit_release_discovery_tpg();
587 	kmem_cache_destroy(lio_cmd_cache);
588 	kmem_cache_destroy(lio_qr_cache);
589 	kmem_cache_destroy(lio_dr_cache);
590 	kmem_cache_destroy(lio_ooo_cache);
591 	kmem_cache_destroy(lio_r2t_cache);
592 
593 	iscsi_target_deregister_configfs();
594 
595 	kfree(iscsit_global);
596 }
597 
598 static int iscsit_add_reject(
599 	u8 reason,
600 	int fail_conn,
601 	unsigned char *buf,
602 	struct iscsi_conn *conn)
603 {
604 	struct iscsi_cmd *cmd;
605 	struct iscsi_reject *hdr;
606 	int ret;
607 
608 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
609 	if (!cmd)
610 		return -1;
611 
612 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
613 	if (fail_conn)
614 		cmd->cmd_flags |= ICF_REJECT_FAIL_CONN;
615 
616 	hdr	= (struct iscsi_reject *) cmd->pdu;
617 	hdr->reason = reason;
618 
619 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
620 	if (!cmd->buf_ptr) {
621 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
622 		iscsit_release_cmd(cmd);
623 		return -1;
624 	}
625 
626 	spin_lock_bh(&conn->cmd_lock);
627 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
628 	spin_unlock_bh(&conn->cmd_lock);
629 
630 	cmd->i_state = ISTATE_SEND_REJECT;
631 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
632 
633 	ret = wait_for_completion_interruptible(&cmd->reject_comp);
634 	if (ret != 0)
635 		return -1;
636 
637 	return (!fail_conn) ? 0 : -1;
638 }
639 
640 int iscsit_add_reject_from_cmd(
641 	u8 reason,
642 	int fail_conn,
643 	int add_to_conn,
644 	unsigned char *buf,
645 	struct iscsi_cmd *cmd)
646 {
647 	struct iscsi_conn *conn;
648 	struct iscsi_reject *hdr;
649 	int ret;
650 
651 	if (!cmd->conn) {
652 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
653 				cmd->init_task_tag);
654 		return -1;
655 	}
656 	conn = cmd->conn;
657 
658 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
659 	if (fail_conn)
660 		cmd->cmd_flags |= ICF_REJECT_FAIL_CONN;
661 
662 	hdr	= (struct iscsi_reject *) cmd->pdu;
663 	hdr->reason = reason;
664 
665 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
666 	if (!cmd->buf_ptr) {
667 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
668 		iscsit_release_cmd(cmd);
669 		return -1;
670 	}
671 
672 	if (add_to_conn) {
673 		spin_lock_bh(&conn->cmd_lock);
674 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
675 		spin_unlock_bh(&conn->cmd_lock);
676 	}
677 
678 	cmd->i_state = ISTATE_SEND_REJECT;
679 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
680 
681 	ret = wait_for_completion_interruptible(&cmd->reject_comp);
682 	if (ret != 0)
683 		return -1;
684 
685 	return (!fail_conn) ? 0 : -1;
686 }
687 
688 /*
689  * Map some portion of the allocated scatterlist to an iovec, suitable for
690  * kernel sockets to copy data in/out.
691  */
692 static int iscsit_map_iovec(
693 	struct iscsi_cmd *cmd,
694 	struct kvec *iov,
695 	u32 data_offset,
696 	u32 data_length)
697 {
698 	u32 i = 0;
699 	struct scatterlist *sg;
700 	unsigned int page_off;
701 
702 	/*
703 	 * We know each entry in t_data_sg contains a page.
704 	 */
705 	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
706 	page_off = (data_offset % PAGE_SIZE);
707 
708 	cmd->first_data_sg = sg;
709 	cmd->first_data_sg_off = page_off;
710 
711 	while (data_length) {
712 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
713 
714 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
715 		iov[i].iov_len = cur_len;
716 
717 		data_length -= cur_len;
718 		page_off = 0;
719 		sg = sg_next(sg);
720 		i++;
721 	}
722 
723 	cmd->kmapped_nents = i;
724 
725 	return i;
726 }
727 
728 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
729 {
730 	u32 i;
731 	struct scatterlist *sg;
732 
733 	sg = cmd->first_data_sg;
734 
735 	for (i = 0; i < cmd->kmapped_nents; i++)
736 		kunmap(sg_page(&sg[i]));
737 }
738 
739 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
740 {
741 	struct iscsi_cmd *cmd;
742 
743 	conn->exp_statsn = exp_statsn;
744 
745 	spin_lock_bh(&conn->cmd_lock);
746 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
747 		spin_lock(&cmd->istate_lock);
748 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
749 		    (cmd->stat_sn < exp_statsn)) {
750 			cmd->i_state = ISTATE_REMOVE;
751 			spin_unlock(&cmd->istate_lock);
752 			iscsit_add_cmd_to_immediate_queue(cmd, conn,
753 						cmd->i_state);
754 			continue;
755 		}
756 		spin_unlock(&cmd->istate_lock);
757 	}
758 	spin_unlock_bh(&conn->cmd_lock);
759 }
760 
761 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
762 {
763 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
764 
765 	iov_count += ISCSI_IOV_DATA_BUFFER;
766 
767 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
768 	if (!cmd->iov_data) {
769 		pr_err("Unable to allocate cmd->iov_data\n");
770 		return -ENOMEM;
771 	}
772 
773 	cmd->orig_iov_data_count = iov_count;
774 	return 0;
775 }
776 
777 static int iscsit_handle_scsi_cmd(
778 	struct iscsi_conn *conn,
779 	unsigned char *buf)
780 {
781 	int	data_direction, cmdsn_ret = 0, immed_ret, ret, transport_ret;
782 	int	dump_immediate_data = 0, send_check_condition = 0, payload_length;
783 	struct iscsi_cmd	*cmd = NULL;
784 	struct iscsi_scsi_req *hdr;
785 	int iscsi_task_attr;
786 	int sam_task_attr;
787 
788 	spin_lock_bh(&conn->sess->session_stats_lock);
789 	conn->sess->cmd_pdus++;
790 	if (conn->sess->se_sess->se_node_acl) {
791 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
792 		conn->sess->se_sess->se_node_acl->num_cmds++;
793 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
794 	}
795 	spin_unlock_bh(&conn->sess->session_stats_lock);
796 
797 	hdr			= (struct iscsi_scsi_req *) buf;
798 	payload_length		= ntoh24(hdr->dlength);
799 	hdr->itt		= be32_to_cpu(hdr->itt);
800 	hdr->data_length	= be32_to_cpu(hdr->data_length);
801 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
802 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
803 
804 	/* FIXME; Add checks for AdditionalHeaderSegment */
805 
806 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
807 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
808 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
809 				" not set. Bad iSCSI Initiator.\n");
810 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
811 				buf, conn);
812 	}
813 
814 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
815 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
816 		/*
817 		 * Vmware ESX v3.0 uses a modified Cisco Initiator (v3.4.2)
818 		 * that adds support for RESERVE/RELEASE.  There is a bug
819 		 * add with this new functionality that sets R/W bits when
820 		 * neither CDB carries any READ or WRITE datapayloads.
821 		 */
822 		if ((hdr->cdb[0] == 0x16) || (hdr->cdb[0] == 0x17)) {
823 			hdr->flags &= ~ISCSI_FLAG_CMD_READ;
824 			hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
825 			goto done;
826 		}
827 
828 		pr_err("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
829 			" set when Expected Data Transfer Length is 0 for"
830 			" CDB: 0x%02x. Bad iSCSI Initiator.\n", hdr->cdb[0]);
831 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
832 				buf, conn);
833 	}
834 done:
835 
836 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
837 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
838 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
839 			" MUST be set if Expected Data Transfer Length is not 0."
840 			" Bad iSCSI Initiator\n");
841 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
842 				buf, conn);
843 	}
844 
845 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
846 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
847 		pr_err("Bidirectional operations not supported!\n");
848 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
849 				buf, conn);
850 	}
851 
852 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
853 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
854 				" Scsi Command PDU.\n");
855 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
856 				buf, conn);
857 	}
858 
859 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
860 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
861 			" protocol error.\n", payload_length);
862 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
863 				buf, conn);
864 	}
865 
866 	if ((hdr->data_length == payload_length) &&
867 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
868 		pr_err("Expected Data Transfer Length and Length of"
869 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
870 			" bit is not set protocol error\n");
871 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
872 				buf, conn);
873 	}
874 
875 	if (payload_length > hdr->data_length) {
876 		pr_err("DataSegmentLength: %u is greater than"
877 			" EDTL: %u, protocol error.\n", payload_length,
878 				hdr->data_length);
879 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
880 				buf, conn);
881 	}
882 
883 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
884 		pr_err("DataSegmentLength: %u is greater than"
885 			" MaxRecvDataSegmentLength: %u, protocol error.\n",
886 			payload_length, conn->conn_ops->MaxRecvDataSegmentLength);
887 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
888 				buf, conn);
889 	}
890 
891 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
892 		pr_err("DataSegmentLength: %u is greater than"
893 			" FirstBurstLength: %u, protocol error.\n",
894 			payload_length, conn->sess->sess_ops->FirstBurstLength);
895 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
896 					buf, conn);
897 	}
898 
899 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
900 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
901 			  DMA_NONE;
902 
903 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
904 	if (!cmd)
905 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES, 1,
906 					 buf, conn);
907 
908 	cmd->data_direction = data_direction;
909 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
910 	/*
911 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
912 	 */
913 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
914 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
915 		sam_task_attr = MSG_SIMPLE_TAG;
916 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
917 		sam_task_attr = MSG_ORDERED_TAG;
918 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
919 		sam_task_attr = MSG_HEAD_TAG;
920 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
921 		sam_task_attr = MSG_ACA_TAG;
922 	else {
923 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
924 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
925 		sam_task_attr = MSG_SIMPLE_TAG;
926 	}
927 
928 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
929 	cmd->i_state		= ISTATE_NEW_CMD;
930 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
931 	cmd->immediate_data	= (payload_length) ? 1 : 0;
932 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
933 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
934 	if (cmd->unsolicited_data)
935 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
936 
937 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
938 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
939 		spin_lock_bh(&conn->sess->ttt_lock);
940 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
941 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
942 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
943 		spin_unlock_bh(&conn->sess->ttt_lock);
944 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
945 		cmd->targ_xfer_tag = 0xFFFFFFFF;
946 	cmd->cmd_sn		= hdr->cmdsn;
947 	cmd->exp_stat_sn	= hdr->exp_statsn;
948 	cmd->first_burst_len	= payload_length;
949 
950 	if (cmd->data_direction == DMA_FROM_DEVICE) {
951 		struct iscsi_datain_req *dr;
952 
953 		dr = iscsit_allocate_datain_req();
954 		if (!dr)
955 			return iscsit_add_reject_from_cmd(
956 					ISCSI_REASON_BOOKMARK_NO_RESOURCES,
957 					1, 1, buf, cmd);
958 
959 		iscsit_attach_datain_req(cmd, dr);
960 	}
961 
962 	/*
963 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
964 	 */
965 	transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
966 			conn->sess->se_sess, hdr->data_length, cmd->data_direction,
967 			sam_task_attr, &cmd->sense_buffer[0]);
968 
969 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
970 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
971 		hdr->cmdsn, hdr->data_length, payload_length, conn->cid);
972 
973 	/*
974 	 * The CDB is going to an se_device_t.
975 	 */
976 	ret = transport_lookup_cmd_lun(&cmd->se_cmd,
977 				       scsilun_to_int(&hdr->lun));
978 	if (ret < 0) {
979 		if (cmd->se_cmd.scsi_sense_reason == TCM_NON_EXISTENT_LUN) {
980 			pr_debug("Responding to non-acl'ed,"
981 				" non-existent or non-exported iSCSI LUN:"
982 				" 0x%016Lx\n", get_unaligned_le64(&hdr->lun));
983 		}
984 		send_check_condition = 1;
985 		goto attach_cmd;
986 	}
987 
988 	transport_ret = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
989 	if (transport_ret == -ENOMEM) {
990 		return iscsit_add_reject_from_cmd(
991 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
992 				1, 1, buf, cmd);
993 	} else if (transport_ret < 0) {
994 		/*
995 		 * Unsupported SAM Opcode.  CHECK_CONDITION will be sent
996 		 * in iscsit_execute_cmd() during the CmdSN OOO Execution
997 		 * Mechinism.
998 		 */
999 		send_check_condition = 1;
1000 	} else {
1001 		if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0)
1002 			return iscsit_add_reject_from_cmd(
1003 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1004 				1, 1, buf, cmd);
1005 	}
1006 
1007 attach_cmd:
1008 	spin_lock_bh(&conn->cmd_lock);
1009 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1010 	spin_unlock_bh(&conn->cmd_lock);
1011 	/*
1012 	 * Check if we need to delay processing because of ALUA
1013 	 * Active/NonOptimized primary access state..
1014 	 */
1015 	core_alua_check_nonop_delay(&cmd->se_cmd);
1016 
1017 	ret = iscsit_allocate_iovecs(cmd);
1018 	if (ret < 0)
1019 		return iscsit_add_reject_from_cmd(
1020 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1021 				1, 0, buf, cmd);
1022 	/*
1023 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1024 	 * the Immediate Bit is not set, and no Immediate
1025 	 * Data is attached.
1026 	 *
1027 	 * A PDU/CmdSN carrying Immediate Data can only
1028 	 * be processed after the DataCRC has passed.
1029 	 * If the DataCRC fails, the CmdSN MUST NOT
1030 	 * be acknowledged. (See below)
1031 	 */
1032 	if (!cmd->immediate_data) {
1033 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1034 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1035 			return 0;
1036 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1037 			return iscsit_add_reject_from_cmd(
1038 				ISCSI_REASON_PROTOCOL_ERROR,
1039 				1, 0, buf, cmd);
1040 	}
1041 
1042 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1043 
1044 	/*
1045 	 * If no Immediate Data is attached, it's OK to return now.
1046 	 */
1047 	if (!cmd->immediate_data) {
1048 		if (send_check_condition)
1049 			return 0;
1050 
1051 		if (cmd->unsolicited_data) {
1052 			iscsit_set_dataout_sequence_values(cmd);
1053 
1054 			spin_lock_bh(&cmd->dataout_timeout_lock);
1055 			iscsit_start_dataout_timer(cmd, cmd->conn);
1056 			spin_unlock_bh(&cmd->dataout_timeout_lock);
1057 		}
1058 
1059 		return 0;
1060 	}
1061 
1062 	/*
1063 	 * Early CHECK_CONDITIONs never make it to the transport processing
1064 	 * thread.  They are processed in CmdSN order by
1065 	 * iscsit_check_received_cmdsn() below.
1066 	 */
1067 	if (send_check_condition) {
1068 		immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1069 		dump_immediate_data = 1;
1070 		goto after_immediate_data;
1071 	}
1072 	/*
1073 	 * Call directly into transport_generic_new_cmd() to perform
1074 	 * the backend memory allocation.
1075 	 */
1076 	ret = transport_generic_new_cmd(&cmd->se_cmd);
1077 	if (ret < 0) {
1078 		immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1079 		dump_immediate_data = 1;
1080 		goto after_immediate_data;
1081 	}
1082 
1083 	immed_ret = iscsit_handle_immediate_data(cmd, buf, payload_length);
1084 after_immediate_data:
1085 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1086 		/*
1087 		 * A PDU/CmdSN carrying Immediate Data passed
1088 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1089 		 * Immediate Bit is not set.
1090 		 */
1091 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1092 		/*
1093 		 * Special case for Unsupported SAM WRITE Opcodes
1094 		 * and ImmediateData=Yes.
1095 		 */
1096 		if (dump_immediate_data) {
1097 			if (iscsit_dump_data_payload(conn, payload_length, 1) < 0)
1098 				return -1;
1099 		} else if (cmd->unsolicited_data) {
1100 			iscsit_set_dataout_sequence_values(cmd);
1101 
1102 			spin_lock_bh(&cmd->dataout_timeout_lock);
1103 			iscsit_start_dataout_timer(cmd, cmd->conn);
1104 			spin_unlock_bh(&cmd->dataout_timeout_lock);
1105 		}
1106 
1107 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1108 			return iscsit_add_reject_from_cmd(
1109 				ISCSI_REASON_PROTOCOL_ERROR,
1110 				1, 0, buf, cmd);
1111 
1112 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1113 		/*
1114 		 * Immediate Data failed DataCRC and ERL>=1,
1115 		 * silently drop this PDU and let the initiator
1116 		 * plug the CmdSN gap.
1117 		 *
1118 		 * FIXME: Send Unsolicited NOPIN with reserved
1119 		 * TTT here to help the initiator figure out
1120 		 * the missing CmdSN, although they should be
1121 		 * intelligent enough to determine the missing
1122 		 * CmdSN and issue a retry to plug the sequence.
1123 		 */
1124 		cmd->i_state = ISTATE_REMOVE;
1125 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
1126 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1127 		return -1;
1128 
1129 	return 0;
1130 }
1131 
1132 static u32 iscsit_do_crypto_hash_sg(
1133 	struct hash_desc *hash,
1134 	struct iscsi_cmd *cmd,
1135 	u32 data_offset,
1136 	u32 data_length,
1137 	u32 padding,
1138 	u8 *pad_bytes)
1139 {
1140 	u32 data_crc;
1141 	u32 i;
1142 	struct scatterlist *sg;
1143 	unsigned int page_off;
1144 
1145 	crypto_hash_init(hash);
1146 
1147 	sg = cmd->first_data_sg;
1148 	page_off = cmd->first_data_sg_off;
1149 
1150 	i = 0;
1151 	while (data_length) {
1152 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1153 
1154 		crypto_hash_update(hash, &sg[i], cur_len);
1155 
1156 		data_length -= cur_len;
1157 		page_off = 0;
1158 		i++;
1159 	}
1160 
1161 	if (padding) {
1162 		struct scatterlist pad_sg;
1163 
1164 		sg_init_one(&pad_sg, pad_bytes, padding);
1165 		crypto_hash_update(hash, &pad_sg, padding);
1166 	}
1167 	crypto_hash_final(hash, (u8 *) &data_crc);
1168 
1169 	return data_crc;
1170 }
1171 
1172 static void iscsit_do_crypto_hash_buf(
1173 	struct hash_desc *hash,
1174 	unsigned char *buf,
1175 	u32 payload_length,
1176 	u32 padding,
1177 	u8 *pad_bytes,
1178 	u8 *data_crc)
1179 {
1180 	struct scatterlist sg;
1181 
1182 	crypto_hash_init(hash);
1183 
1184 	sg_init_one(&sg, buf, payload_length);
1185 	crypto_hash_update(hash, &sg, payload_length);
1186 
1187 	if (padding) {
1188 		sg_init_one(&sg, pad_bytes, padding);
1189 		crypto_hash_update(hash, &sg, padding);
1190 	}
1191 	crypto_hash_final(hash, data_crc);
1192 }
1193 
1194 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1195 {
1196 	int iov_ret, ooo_cmdsn = 0, ret;
1197 	u8 data_crc_failed = 0;
1198 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0;
1199 	u32 rx_size = 0, payload_length;
1200 	struct iscsi_cmd *cmd = NULL;
1201 	struct se_cmd *se_cmd;
1202 	struct iscsi_data *hdr;
1203 	struct kvec *iov;
1204 	unsigned long flags;
1205 
1206 	hdr			= (struct iscsi_data *) buf;
1207 	payload_length		= ntoh24(hdr->dlength);
1208 	hdr->itt		= be32_to_cpu(hdr->itt);
1209 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1210 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1211 	hdr->datasn		= be32_to_cpu(hdr->datasn);
1212 	hdr->offset		= be32_to_cpu(hdr->offset);
1213 
1214 	if (!payload_length) {
1215 		pr_err("DataOUT payload is ZERO, protocol error.\n");
1216 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1217 					buf, conn);
1218 	}
1219 
1220 	/* iSCSI write */
1221 	spin_lock_bh(&conn->sess->session_stats_lock);
1222 	conn->sess->rx_data_octets += payload_length;
1223 	if (conn->sess->se_sess->se_node_acl) {
1224 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
1225 		conn->sess->se_sess->se_node_acl->write_bytes += payload_length;
1226 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
1227 	}
1228 	spin_unlock_bh(&conn->sess->session_stats_lock);
1229 
1230 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1231 		pr_err("DataSegmentLength: %u is greater than"
1232 			" MaxRecvDataSegmentLength: %u\n", payload_length,
1233 			conn->conn_ops->MaxRecvDataSegmentLength);
1234 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1235 					buf, conn);
1236 	}
1237 
1238 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1239 			payload_length);
1240 	if (!cmd)
1241 		return 0;
1242 
1243 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1244 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1245 		hdr->itt, hdr->ttt, hdr->datasn, hdr->offset,
1246 		payload_length, conn->cid);
1247 
1248 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1249 		pr_err("Command ITT: 0x%08x received DataOUT after"
1250 			" last DataOUT received, dumping payload\n",
1251 			cmd->init_task_tag);
1252 		return iscsit_dump_data_payload(conn, payload_length, 1);
1253 	}
1254 
1255 	if (cmd->data_direction != DMA_TO_DEVICE) {
1256 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1257 			" NON-WRITE command.\n", cmd->init_task_tag);
1258 		return iscsit_add_reject_from_cmd(ISCSI_REASON_PROTOCOL_ERROR,
1259 				1, 0, buf, cmd);
1260 	}
1261 	se_cmd = &cmd->se_cmd;
1262 	iscsit_mod_dataout_timer(cmd);
1263 
1264 	if ((hdr->offset + payload_length) > cmd->se_cmd.data_length) {
1265 		pr_err("DataOut Offset: %u, Length %u greater than"
1266 			" iSCSI Command EDTL %u, protocol error.\n",
1267 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1268 		return iscsit_add_reject_from_cmd(ISCSI_REASON_BOOKMARK_INVALID,
1269 				1, 0, buf, cmd);
1270 	}
1271 
1272 	if (cmd->unsolicited_data) {
1273 		int dump_unsolicited_data = 0;
1274 
1275 		if (conn->sess->sess_ops->InitialR2T) {
1276 			pr_err("Received unexpected unsolicited data"
1277 				" while InitialR2T=Yes, protocol error.\n");
1278 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1279 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1280 			return -1;
1281 		}
1282 		/*
1283 		 * Special case for dealing with Unsolicited DataOUT
1284 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1285 		 * failures;
1286 		 */
1287 
1288 		/* Something's amiss if we're not in WRITE_PENDING state... */
1289 		spin_lock_irqsave(&se_cmd->t_state_lock, flags);
1290 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1291 		spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
1292 
1293 		spin_lock_irqsave(&se_cmd->t_state_lock, flags);
1294 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) ||
1295 		     (se_cmd->se_cmd_flags & SCF_SCSI_CDB_EXCEPTION))
1296 			dump_unsolicited_data = 1;
1297 		spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
1298 
1299 		if (dump_unsolicited_data) {
1300 			/*
1301 			 * Check if a delayed TASK_ABORTED status needs to
1302 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1303 			 * received with the unsolicitied data out.
1304 			 */
1305 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1306 				iscsit_stop_dataout_timer(cmd);
1307 
1308 			transport_check_aborted_status(se_cmd,
1309 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1310 			return iscsit_dump_data_payload(conn, payload_length, 1);
1311 		}
1312 	} else {
1313 		/*
1314 		 * For the normal solicited data path:
1315 		 *
1316 		 * Check for a delayed TASK_ABORTED status and dump any
1317 		 * incoming data out payload if one exists.  Also, when the
1318 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1319 		 * data out sequence, we decrement outstanding_r2ts.  Once
1320 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1321 		 * TASK_ABORTED status.
1322 		 */
1323 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1324 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1325 				if (--cmd->outstanding_r2ts < 1) {
1326 					iscsit_stop_dataout_timer(cmd);
1327 					transport_check_aborted_status(
1328 							se_cmd, 1);
1329 				}
1330 
1331 			return iscsit_dump_data_payload(conn, payload_length, 1);
1332 		}
1333 	}
1334 	/*
1335 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1336 	 * within-command recovery checks before receiving the payload.
1337 	 */
1338 	ret = iscsit_check_pre_dataout(cmd, buf);
1339 	if (ret == DATAOUT_WITHIN_COMMAND_RECOVERY)
1340 		return 0;
1341 	else if (ret == DATAOUT_CANNOT_RECOVER)
1342 		return -1;
1343 
1344 	rx_size += payload_length;
1345 	iov = &cmd->iov_data[0];
1346 
1347 	iov_ret = iscsit_map_iovec(cmd, iov, hdr->offset, payload_length);
1348 	if (iov_ret < 0)
1349 		return -1;
1350 
1351 	iov_count += iov_ret;
1352 
1353 	padding = ((-payload_length) & 3);
1354 	if (padding != 0) {
1355 		iov[iov_count].iov_base	= cmd->pad_bytes;
1356 		iov[iov_count++].iov_len = padding;
1357 		rx_size += padding;
1358 		pr_debug("Receiving %u padding bytes.\n", padding);
1359 	}
1360 
1361 	if (conn->conn_ops->DataDigest) {
1362 		iov[iov_count].iov_base = &checksum;
1363 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1364 		rx_size += ISCSI_CRC_LEN;
1365 	}
1366 
1367 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1368 
1369 	iscsit_unmap_iovec(cmd);
1370 
1371 	if (rx_got != rx_size)
1372 		return -1;
1373 
1374 	if (conn->conn_ops->DataDigest) {
1375 		u32 data_crc;
1376 
1377 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1378 						    hdr->offset, payload_length, padding,
1379 						    cmd->pad_bytes);
1380 
1381 		if (checksum != data_crc) {
1382 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1383 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1384 				" does not match computed 0x%08x\n",
1385 				hdr->itt, hdr->offset, payload_length,
1386 				hdr->datasn, checksum, data_crc);
1387 			data_crc_failed = 1;
1388 		} else {
1389 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1390 				" %u bytes of Data Out\n", checksum,
1391 				payload_length);
1392 		}
1393 	}
1394 	/*
1395 	 * Increment post receive data and CRC values or perform
1396 	 * within-command recovery.
1397 	 */
1398 	ret = iscsit_check_post_dataout(cmd, buf, data_crc_failed);
1399 	if ((ret == DATAOUT_NORMAL) || (ret == DATAOUT_WITHIN_COMMAND_RECOVERY))
1400 		return 0;
1401 	else if (ret == DATAOUT_SEND_R2T) {
1402 		iscsit_set_dataout_sequence_values(cmd);
1403 		iscsit_build_r2ts_for_cmd(cmd, conn, false);
1404 	} else if (ret == DATAOUT_SEND_TO_TRANSPORT) {
1405 		/*
1406 		 * Handle extra special case for out of order
1407 		 * Unsolicited Data Out.
1408 		 */
1409 		spin_lock_bh(&cmd->istate_lock);
1410 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1411 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1412 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1413 		spin_unlock_bh(&cmd->istate_lock);
1414 
1415 		iscsit_stop_dataout_timer(cmd);
1416 		return (!ooo_cmdsn) ? transport_generic_handle_data(
1417 					&cmd->se_cmd) : 0;
1418 	} else /* DATAOUT_CANNOT_RECOVER */
1419 		return -1;
1420 
1421 	return 0;
1422 }
1423 
1424 static int iscsit_handle_nop_out(
1425 	struct iscsi_conn *conn,
1426 	unsigned char *buf)
1427 {
1428 	unsigned char *ping_data = NULL;
1429 	int cmdsn_ret, niov = 0, ret = 0, rx_got, rx_size;
1430 	u32 checksum, data_crc, padding = 0, payload_length;
1431 	struct iscsi_cmd *cmd = NULL;
1432 	struct kvec *iov = NULL;
1433 	struct iscsi_nopout *hdr;
1434 
1435 	hdr			= (struct iscsi_nopout *) buf;
1436 	payload_length		= ntoh24(hdr->dlength);
1437 	hdr->itt		= be32_to_cpu(hdr->itt);
1438 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1439 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1440 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1441 
1442 	if ((hdr->itt == 0xFFFFFFFF) && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1443 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1444 			" not set, protocol error.\n");
1445 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1446 					buf, conn);
1447 	}
1448 
1449 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1450 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1451 			" greater than MaxRecvDataSegmentLength: %u, protocol"
1452 			" error.\n", payload_length,
1453 			conn->conn_ops->MaxRecvDataSegmentLength);
1454 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1455 					buf, conn);
1456 	}
1457 
1458 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%09x,"
1459 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1460 		(hdr->itt == 0xFFFFFFFF) ? "Response" : "Request",
1461 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1462 		payload_length);
1463 	/*
1464 	 * This is not a response to a Unsolicited NopIN, which means
1465 	 * it can either be a NOPOUT ping request (with a valid ITT),
1466 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1467 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1468 	 * can contain ping data.
1469 	 */
1470 	if (hdr->ttt == 0xFFFFFFFF) {
1471 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1472 		if (!cmd)
1473 			return iscsit_add_reject(
1474 					ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1475 					1, buf, conn);
1476 
1477 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1478 		cmd->i_state		= ISTATE_SEND_NOPIN;
1479 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1480 						1 : 0);
1481 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1482 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1483 		cmd->cmd_sn		= hdr->cmdsn;
1484 		cmd->exp_stat_sn	= hdr->exp_statsn;
1485 		cmd->data_direction	= DMA_NONE;
1486 	}
1487 
1488 	if (payload_length && (hdr->ttt == 0xFFFFFFFF)) {
1489 		rx_size = payload_length;
1490 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1491 		if (!ping_data) {
1492 			pr_err("Unable to allocate memory for"
1493 				" NOPOUT ping data.\n");
1494 			ret = -1;
1495 			goto out;
1496 		}
1497 
1498 		iov = &cmd->iov_misc[0];
1499 		iov[niov].iov_base	= ping_data;
1500 		iov[niov++].iov_len	= payload_length;
1501 
1502 		padding = ((-payload_length) & 3);
1503 		if (padding != 0) {
1504 			pr_debug("Receiving %u additional bytes"
1505 				" for padding.\n", padding);
1506 			iov[niov].iov_base	= &cmd->pad_bytes;
1507 			iov[niov++].iov_len	= padding;
1508 			rx_size += padding;
1509 		}
1510 		if (conn->conn_ops->DataDigest) {
1511 			iov[niov].iov_base	= &checksum;
1512 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1513 			rx_size += ISCSI_CRC_LEN;
1514 		}
1515 
1516 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1517 		if (rx_got != rx_size) {
1518 			ret = -1;
1519 			goto out;
1520 		}
1521 
1522 		if (conn->conn_ops->DataDigest) {
1523 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1524 					ping_data, payload_length,
1525 					padding, cmd->pad_bytes,
1526 					(u8 *)&data_crc);
1527 
1528 			if (checksum != data_crc) {
1529 				pr_err("Ping data CRC32C DataDigest"
1530 				" 0x%08x does not match computed 0x%08x\n",
1531 					checksum, data_crc);
1532 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1533 					pr_err("Unable to recover from"
1534 					" NOPOUT Ping DataCRC failure while in"
1535 						" ERL=0.\n");
1536 					ret = -1;
1537 					goto out;
1538 				} else {
1539 					/*
1540 					 * Silently drop this PDU and let the
1541 					 * initiator plug the CmdSN gap.
1542 					 */
1543 					pr_debug("Dropping NOPOUT"
1544 					" Command CmdSN: 0x%08x due to"
1545 					" DataCRC error.\n", hdr->cmdsn);
1546 					ret = 0;
1547 					goto out;
1548 				}
1549 			} else {
1550 				pr_debug("Got CRC32C DataDigest"
1551 				" 0x%08x for %u bytes of ping data.\n",
1552 					checksum, payload_length);
1553 			}
1554 		}
1555 
1556 		ping_data[payload_length] = '\0';
1557 		/*
1558 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1559 		 */
1560 		cmd->buf_ptr = ping_data;
1561 		cmd->buf_ptr_size = payload_length;
1562 
1563 		pr_debug("Got %u bytes of NOPOUT ping"
1564 			" data.\n", payload_length);
1565 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1566 	}
1567 
1568 	if (hdr->itt != 0xFFFFFFFF) {
1569 		if (!cmd) {
1570 			pr_err("Checking CmdSN for NOPOUT,"
1571 				" but cmd is NULL!\n");
1572 			return -1;
1573 		}
1574 		/*
1575 		 * Initiator is expecting a NopIN ping reply,
1576 		 */
1577 		spin_lock_bh(&conn->cmd_lock);
1578 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1579 		spin_unlock_bh(&conn->cmd_lock);
1580 
1581 		iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1582 
1583 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1584 			iscsit_add_cmd_to_response_queue(cmd, conn,
1585 					cmd->i_state);
1586 			return 0;
1587 		}
1588 
1589 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1590 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1591 			ret = 0;
1592 			goto ping_out;
1593 		}
1594 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1595 			return iscsit_add_reject_from_cmd(
1596 					ISCSI_REASON_PROTOCOL_ERROR,
1597 					1, 0, buf, cmd);
1598 
1599 		return 0;
1600 	}
1601 
1602 	if (hdr->ttt != 0xFFFFFFFF) {
1603 		/*
1604 		 * This was a response to a unsolicited NOPIN ping.
1605 		 */
1606 		cmd = iscsit_find_cmd_from_ttt(conn, hdr->ttt);
1607 		if (!cmd)
1608 			return -1;
1609 
1610 		iscsit_stop_nopin_response_timer(conn);
1611 
1612 		cmd->i_state = ISTATE_REMOVE;
1613 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
1614 		iscsit_start_nopin_timer(conn);
1615 	} else {
1616 		/*
1617 		 * Initiator is not expecting a NOPIN is response.
1618 		 * Just ignore for now.
1619 		 *
1620 		 * iSCSI v19-91 10.18
1621 		 * "A NOP-OUT may also be used to confirm a changed
1622 		 *  ExpStatSN if another PDU will not be available
1623 		 *  for a long time."
1624 		 */
1625 		ret = 0;
1626 		goto out;
1627 	}
1628 
1629 	return 0;
1630 out:
1631 	if (cmd)
1632 		iscsit_release_cmd(cmd);
1633 ping_out:
1634 	kfree(ping_data);
1635 	return ret;
1636 }
1637 
1638 static int iscsit_handle_task_mgt_cmd(
1639 	struct iscsi_conn *conn,
1640 	unsigned char *buf)
1641 {
1642 	struct iscsi_cmd *cmd;
1643 	struct se_tmr_req *se_tmr;
1644 	struct iscsi_tmr_req *tmr_req;
1645 	struct iscsi_tm *hdr;
1646 	int out_of_order_cmdsn = 0;
1647 	int ret;
1648 	u8 function;
1649 
1650 	hdr			= (struct iscsi_tm *) buf;
1651 	hdr->itt		= be32_to_cpu(hdr->itt);
1652 	hdr->rtt		= be32_to_cpu(hdr->rtt);
1653 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1654 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1655 	hdr->refcmdsn		= be32_to_cpu(hdr->refcmdsn);
1656 	hdr->exp_datasn		= be32_to_cpu(hdr->exp_datasn);
1657 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1658 	function = hdr->flags;
1659 
1660 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1661 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1662 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1663 		hdr->rtt, hdr->refcmdsn, conn->cid);
1664 
1665 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1666 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1667 	     (hdr->rtt != ISCSI_RESERVED_TAG))) {
1668 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1669 		hdr->rtt = ISCSI_RESERVED_TAG;
1670 	}
1671 
1672 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1673 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1674 		pr_err("Task Management Request TASK_REASSIGN not"
1675 			" issued as immediate command, bad iSCSI Initiator"
1676 				"implementation\n");
1677 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1678 					buf, conn);
1679 	}
1680 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1681 	    (hdr->refcmdsn != ISCSI_RESERVED_TAG))
1682 		hdr->refcmdsn = ISCSI_RESERVED_TAG;
1683 
1684 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1685 	if (!cmd)
1686 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1687 					 1, buf, conn);
1688 
1689 	cmd->data_direction = DMA_NONE;
1690 
1691 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1692 	if (!cmd->tmr_req) {
1693 		pr_err("Unable to allocate memory for"
1694 			" Task Management command!\n");
1695 		return iscsit_add_reject_from_cmd(
1696 			ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1697 			1, 1, buf, cmd);
1698 	}
1699 
1700 	/*
1701 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1702 	 * LIO-Target $FABRIC_MOD
1703 	 */
1704 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1705 
1706 		u8 tcm_function;
1707 		int ret;
1708 
1709 		transport_init_se_cmd(&cmd->se_cmd,
1710 				      &lio_target_fabric_configfs->tf_ops,
1711 				      conn->sess->se_sess, 0, DMA_NONE,
1712 				      MSG_SIMPLE_TAG, &cmd->sense_buffer[0]);
1713 
1714 		switch (function) {
1715 		case ISCSI_TM_FUNC_ABORT_TASK:
1716 			tcm_function = TMR_ABORT_TASK;
1717 			break;
1718 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1719 			tcm_function = TMR_ABORT_TASK_SET;
1720 			break;
1721 		case ISCSI_TM_FUNC_CLEAR_ACA:
1722 			tcm_function = TMR_CLEAR_ACA;
1723 			break;
1724 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1725 			tcm_function = TMR_CLEAR_TASK_SET;
1726 			break;
1727 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1728 			tcm_function = TMR_LUN_RESET;
1729 			break;
1730 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1731 			tcm_function = TMR_TARGET_WARM_RESET;
1732 			break;
1733 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1734 			tcm_function = TMR_TARGET_COLD_RESET;
1735 			break;
1736 		default:
1737 			pr_err("Unknown iSCSI TMR Function:"
1738 			       " 0x%02x\n", function);
1739 			return iscsit_add_reject_from_cmd(
1740 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1741 				1, 1, buf, cmd);
1742 		}
1743 
1744 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1745 					 tcm_function, GFP_KERNEL);
1746 		if (ret < 0)
1747 			return iscsit_add_reject_from_cmd(
1748 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1749 				1, 1, buf, cmd);
1750 
1751 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1752 	}
1753 
1754 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1755 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1756 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1757 	cmd->init_task_tag	= hdr->itt;
1758 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1759 	cmd->cmd_sn		= hdr->cmdsn;
1760 	cmd->exp_stat_sn	= hdr->exp_statsn;
1761 	se_tmr			= cmd->se_cmd.se_tmr_req;
1762 	tmr_req			= cmd->tmr_req;
1763 	/*
1764 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1765 	 */
1766 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1767 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1768 					       scsilun_to_int(&hdr->lun));
1769 		if (ret < 0) {
1770 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1771 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1772 			goto attach;
1773 		}
1774 	}
1775 
1776 	switch (function) {
1777 	case ISCSI_TM_FUNC_ABORT_TASK:
1778 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1779 		if (se_tmr->response != ISCSI_TMF_RSP_COMPLETE) {
1780 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1781 			goto attach;
1782 		}
1783 		break;
1784 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1785 	case ISCSI_TM_FUNC_CLEAR_ACA:
1786 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1787 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1788 		break;
1789 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1790 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1791 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1792 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1793 			goto attach;
1794 		}
1795 		break;
1796 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1797 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1798 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1799 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1800 			goto attach;
1801 		}
1802 		break;
1803 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1804 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1805 		/*
1806 		 * Perform sanity checks on the ExpDataSN only if the
1807 		 * TASK_REASSIGN was successful.
1808 		 */
1809 		if (se_tmr->response != ISCSI_TMF_RSP_COMPLETE)
1810 			break;
1811 
1812 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1813 			return iscsit_add_reject_from_cmd(
1814 					ISCSI_REASON_BOOKMARK_INVALID, 1, 1,
1815 					buf, cmd);
1816 		break;
1817 	default:
1818 		pr_err("Unknown TMR function: 0x%02x, protocol"
1819 			" error.\n", function);
1820 		cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1821 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1822 		goto attach;
1823 	}
1824 
1825 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1826 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1827 		se_tmr->call_transport = 1;
1828 attach:
1829 	spin_lock_bh(&conn->cmd_lock);
1830 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1831 	spin_unlock_bh(&conn->cmd_lock);
1832 
1833 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1834 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1835 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1836 			out_of_order_cmdsn = 1;
1837 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1838 			return 0;
1839 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1840 			return iscsit_add_reject_from_cmd(
1841 					ISCSI_REASON_PROTOCOL_ERROR,
1842 					1, 0, buf, cmd);
1843 	}
1844 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1845 
1846 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1847 		return 0;
1848 	/*
1849 	 * Found the referenced task, send to transport for processing.
1850 	 */
1851 	if (se_tmr->call_transport)
1852 		return transport_generic_handle_tmr(&cmd->se_cmd);
1853 
1854 	/*
1855 	 * Could not find the referenced LUN, task, or Task Management
1856 	 * command not authorized or supported.  Change state and
1857 	 * let the tx_thread send the response.
1858 	 *
1859 	 * For connection recovery, this is also the default action for
1860 	 * TMR TASK_REASSIGN.
1861 	 */
1862 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1863 	return 0;
1864 }
1865 
1866 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1867 static int iscsit_handle_text_cmd(
1868 	struct iscsi_conn *conn,
1869 	unsigned char *buf)
1870 {
1871 	char *text_ptr, *text_in;
1872 	int cmdsn_ret, niov = 0, rx_got, rx_size;
1873 	u32 checksum = 0, data_crc = 0, payload_length;
1874 	u32 padding = 0, pad_bytes = 0, text_length = 0;
1875 	struct iscsi_cmd *cmd;
1876 	struct kvec iov[3];
1877 	struct iscsi_text *hdr;
1878 
1879 	hdr			= (struct iscsi_text *) buf;
1880 	payload_length		= ntoh24(hdr->dlength);
1881 	hdr->itt		= be32_to_cpu(hdr->itt);
1882 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1883 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1884 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1885 
1886 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1887 		pr_err("Unable to accept text parameter length: %u"
1888 			"greater than MaxRecvDataSegmentLength %u.\n",
1889 		       payload_length, conn->conn_ops->MaxRecvDataSegmentLength);
1890 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1891 					buf, conn);
1892 	}
1893 
1894 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1895 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1896 		hdr->exp_statsn, payload_length);
1897 
1898 	rx_size = text_length = payload_length;
1899 	if (text_length) {
1900 		text_in = kzalloc(text_length, GFP_KERNEL);
1901 		if (!text_in) {
1902 			pr_err("Unable to allocate memory for"
1903 				" incoming text parameters\n");
1904 			return -1;
1905 		}
1906 
1907 		memset(iov, 0, 3 * sizeof(struct kvec));
1908 		iov[niov].iov_base	= text_in;
1909 		iov[niov++].iov_len	= text_length;
1910 
1911 		padding = ((-payload_length) & 3);
1912 		if (padding != 0) {
1913 			iov[niov].iov_base = &pad_bytes;
1914 			iov[niov++].iov_len  = padding;
1915 			rx_size += padding;
1916 			pr_debug("Receiving %u additional bytes"
1917 					" for padding.\n", padding);
1918 		}
1919 		if (conn->conn_ops->DataDigest) {
1920 			iov[niov].iov_base	= &checksum;
1921 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1922 			rx_size += ISCSI_CRC_LEN;
1923 		}
1924 
1925 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
1926 		if (rx_got != rx_size) {
1927 			kfree(text_in);
1928 			return -1;
1929 		}
1930 
1931 		if (conn->conn_ops->DataDigest) {
1932 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1933 					text_in, text_length,
1934 					padding, (u8 *)&pad_bytes,
1935 					(u8 *)&data_crc);
1936 
1937 			if (checksum != data_crc) {
1938 				pr_err("Text data CRC32C DataDigest"
1939 					" 0x%08x does not match computed"
1940 					" 0x%08x\n", checksum, data_crc);
1941 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1942 					pr_err("Unable to recover from"
1943 					" Text Data digest failure while in"
1944 						" ERL=0.\n");
1945 					kfree(text_in);
1946 					return -1;
1947 				} else {
1948 					/*
1949 					 * Silently drop this PDU and let the
1950 					 * initiator plug the CmdSN gap.
1951 					 */
1952 					pr_debug("Dropping Text"
1953 					" Command CmdSN: 0x%08x due to"
1954 					" DataCRC error.\n", hdr->cmdsn);
1955 					kfree(text_in);
1956 					return 0;
1957 				}
1958 			} else {
1959 				pr_debug("Got CRC32C DataDigest"
1960 					" 0x%08x for %u bytes of text data.\n",
1961 						checksum, text_length);
1962 			}
1963 		}
1964 		text_in[text_length - 1] = '\0';
1965 		pr_debug("Successfully read %d bytes of text"
1966 				" data.\n", text_length);
1967 
1968 		if (strncmp("SendTargets", text_in, 11) != 0) {
1969 			pr_err("Received Text Data that is not"
1970 				" SendTargets, cannot continue.\n");
1971 			kfree(text_in);
1972 			return -1;
1973 		}
1974 		text_ptr = strchr(text_in, '=');
1975 		if (!text_ptr) {
1976 			pr_err("No \"=\" separator found in Text Data,"
1977 				"  cannot continue.\n");
1978 			kfree(text_in);
1979 			return -1;
1980 		}
1981 		if (strncmp("=All", text_ptr, 4) != 0) {
1982 			pr_err("Unable to locate All value for"
1983 				" SendTargets key,  cannot continue.\n");
1984 			kfree(text_in);
1985 			return -1;
1986 		}
1987 /*#warning Support SendTargets=(iSCSI Target Name/Nothing) values. */
1988 		kfree(text_in);
1989 	}
1990 
1991 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1992 	if (!cmd)
1993 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1994 					1, buf, conn);
1995 
1996 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1997 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1998 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1999 	conn->sess->init_task_tag = cmd->init_task_tag	= hdr->itt;
2000 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2001 	cmd->cmd_sn		= hdr->cmdsn;
2002 	cmd->exp_stat_sn	= hdr->exp_statsn;
2003 	cmd->data_direction	= DMA_NONE;
2004 
2005 	spin_lock_bh(&conn->cmd_lock);
2006 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2007 	spin_unlock_bh(&conn->cmd_lock);
2008 
2009 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
2010 
2011 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2012 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
2013 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2014 			return iscsit_add_reject_from_cmd(
2015 					ISCSI_REASON_PROTOCOL_ERROR,
2016 					1, 0, buf, cmd);
2017 
2018 		return 0;
2019 	}
2020 
2021 	return iscsit_execute_cmd(cmd, 0);
2022 }
2023 
2024 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2025 {
2026 	struct iscsi_conn *conn_p;
2027 	struct iscsi_session *sess = conn->sess;
2028 
2029 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2030 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2031 
2032 	atomic_set(&sess->session_logout, 1);
2033 	atomic_set(&conn->conn_logout_remove, 1);
2034 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2035 
2036 	iscsit_inc_conn_usage_count(conn);
2037 	iscsit_inc_session_usage_count(sess);
2038 
2039 	spin_lock_bh(&sess->conn_lock);
2040 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2041 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2042 			continue;
2043 
2044 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2045 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2046 	}
2047 	spin_unlock_bh(&sess->conn_lock);
2048 
2049 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2050 
2051 	return 0;
2052 }
2053 
2054 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2055 {
2056 	struct iscsi_conn *l_conn;
2057 	struct iscsi_session *sess = conn->sess;
2058 
2059 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2060 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2061 
2062 	/*
2063 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2064 	 * can arrive on a connection with a differing CID.
2065 	 */
2066 	if (conn->cid == cmd->logout_cid) {
2067 		spin_lock_bh(&conn->state_lock);
2068 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2069 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2070 
2071 		atomic_set(&conn->conn_logout_remove, 1);
2072 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2073 		iscsit_inc_conn_usage_count(conn);
2074 
2075 		spin_unlock_bh(&conn->state_lock);
2076 	} else {
2077 		/*
2078 		 * Handle all different cid CLOSECONNECTION requests in
2079 		 * iscsit_logout_post_handler_diffcid() as to give enough
2080 		 * time for any non immediate command's CmdSN to be
2081 		 * acknowledged on the connection in question.
2082 		 *
2083 		 * Here we simply make sure the CID is still around.
2084 		 */
2085 		l_conn = iscsit_get_conn_from_cid(sess,
2086 				cmd->logout_cid);
2087 		if (!l_conn) {
2088 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2089 			iscsit_add_cmd_to_response_queue(cmd, conn,
2090 					cmd->i_state);
2091 			return 0;
2092 		}
2093 
2094 		iscsit_dec_conn_usage_count(l_conn);
2095 	}
2096 
2097 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2098 
2099 	return 0;
2100 }
2101 
2102 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2103 {
2104 	struct iscsi_session *sess = conn->sess;
2105 
2106 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2107 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2108 
2109 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2110 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2111 			" while ERL!=2.\n");
2112 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2113 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2114 		return 0;
2115 	}
2116 
2117 	if (conn->cid == cmd->logout_cid) {
2118 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2119 			" with CID: %hu on CID: %hu, implementation error.\n",
2120 				cmd->logout_cid, conn->cid);
2121 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2122 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2123 		return 0;
2124 	}
2125 
2126 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2127 
2128 	return 0;
2129 }
2130 
2131 static int iscsit_handle_logout_cmd(
2132 	struct iscsi_conn *conn,
2133 	unsigned char *buf)
2134 {
2135 	int cmdsn_ret, logout_remove = 0;
2136 	u8 reason_code = 0;
2137 	struct iscsi_cmd *cmd;
2138 	struct iscsi_logout *hdr;
2139 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2140 
2141 	hdr			= (struct iscsi_logout *) buf;
2142 	reason_code		= (hdr->flags & 0x7f);
2143 	hdr->itt		= be32_to_cpu(hdr->itt);
2144 	hdr->cid		= be16_to_cpu(hdr->cid);
2145 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
2146 	hdr->exp_statsn	= be32_to_cpu(hdr->exp_statsn);
2147 
2148 	if (tiqn) {
2149 		spin_lock(&tiqn->logout_stats.lock);
2150 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2151 			tiqn->logout_stats.normal_logouts++;
2152 		else
2153 			tiqn->logout_stats.abnormal_logouts++;
2154 		spin_unlock(&tiqn->logout_stats.lock);
2155 	}
2156 
2157 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2158 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2159 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2160 		hdr->cid, conn->cid);
2161 
2162 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2163 		pr_err("Received logout request on connection that"
2164 			" is not in logged in state, ignoring request.\n");
2165 		return 0;
2166 	}
2167 
2168 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
2169 	if (!cmd)
2170 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES, 1,
2171 					buf, conn);
2172 
2173 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2174 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2175 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2176 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2177 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2178 	cmd->cmd_sn             = hdr->cmdsn;
2179 	cmd->exp_stat_sn        = hdr->exp_statsn;
2180 	cmd->logout_cid         = hdr->cid;
2181 	cmd->logout_reason      = reason_code;
2182 	cmd->data_direction     = DMA_NONE;
2183 
2184 	/*
2185 	 * We need to sleep in these cases (by returning 1) until the Logout
2186 	 * Response gets sent in the tx thread.
2187 	 */
2188 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2189 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2190 	    (hdr->cid == conn->cid)))
2191 		logout_remove = 1;
2192 
2193 	spin_lock_bh(&conn->cmd_lock);
2194 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2195 	spin_unlock_bh(&conn->cmd_lock);
2196 
2197 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2198 		iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
2199 
2200 	/*
2201 	 * Immediate commands are executed, well, immediately.
2202 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2203 	 */
2204 	if (cmd->immediate_cmd) {
2205 		int ret = iscsit_execute_cmd(cmd, 0);
2206 
2207 		if (ret < 0)
2208 			return ret;
2209 	} else {
2210 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
2211 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2212 			logout_remove = 0;
2213 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2214 			return iscsit_add_reject_from_cmd(
2215 				ISCSI_REASON_PROTOCOL_ERROR,
2216 				1, 0, buf, cmd);
2217 		}
2218 	}
2219 
2220 	return logout_remove;
2221 }
2222 
2223 static int iscsit_handle_snack(
2224 	struct iscsi_conn *conn,
2225 	unsigned char *buf)
2226 {
2227 	struct iscsi_snack *hdr;
2228 
2229 	hdr			= (struct iscsi_snack *) buf;
2230 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2231 	hdr->itt		= be32_to_cpu(hdr->itt);
2232 	hdr->ttt		= be32_to_cpu(hdr->ttt);
2233 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
2234 	hdr->begrun		= be32_to_cpu(hdr->begrun);
2235 	hdr->runlength		= be32_to_cpu(hdr->runlength);
2236 
2237 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2238 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2239 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2240 			hdr->begrun, hdr->runlength, conn->cid);
2241 
2242 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2243 		pr_err("Initiator sent SNACK request while in"
2244 			" ErrorRecoveryLevel=0.\n");
2245 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2246 					buf, conn);
2247 	}
2248 	/*
2249 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2250 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2251 	 */
2252 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2253 	case 0:
2254 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2255 			hdr->itt, hdr->ttt, hdr->begrun, hdr->runlength);
2256 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2257 		return iscsit_handle_status_snack(conn, hdr->itt, hdr->ttt,
2258 			hdr->begrun, hdr->runlength);
2259 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2260 		return iscsit_handle_data_ack(conn, hdr->ttt, hdr->begrun,
2261 			hdr->runlength);
2262 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2263 		/* FIXME: Support R-Data SNACK */
2264 		pr_err("R-Data SNACK Not Supported.\n");
2265 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2266 					buf, conn);
2267 	default:
2268 		pr_err("Unknown SNACK type 0x%02x, protocol"
2269 			" error.\n", hdr->flags & 0x0f);
2270 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2271 					buf, conn);
2272 	}
2273 
2274 	return 0;
2275 }
2276 
2277 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2278 {
2279 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2280 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2281 		wait_for_completion_interruptible_timeout(
2282 					&conn->rx_half_close_comp,
2283 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2284 	}
2285 }
2286 
2287 static int iscsit_handle_immediate_data(
2288 	struct iscsi_cmd *cmd,
2289 	unsigned char *buf,
2290 	u32 length)
2291 {
2292 	int iov_ret, rx_got = 0, rx_size = 0;
2293 	u32 checksum, iov_count = 0, padding = 0;
2294 	struct iscsi_conn *conn = cmd->conn;
2295 	struct kvec *iov;
2296 
2297 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2298 	if (iov_ret < 0)
2299 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2300 
2301 	rx_size = length;
2302 	iov_count = iov_ret;
2303 	iov = &cmd->iov_data[0];
2304 
2305 	padding = ((-length) & 3);
2306 	if (padding != 0) {
2307 		iov[iov_count].iov_base	= cmd->pad_bytes;
2308 		iov[iov_count++].iov_len = padding;
2309 		rx_size += padding;
2310 	}
2311 
2312 	if (conn->conn_ops->DataDigest) {
2313 		iov[iov_count].iov_base		= &checksum;
2314 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2315 		rx_size += ISCSI_CRC_LEN;
2316 	}
2317 
2318 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2319 
2320 	iscsit_unmap_iovec(cmd);
2321 
2322 	if (rx_got != rx_size) {
2323 		iscsit_rx_thread_wait_for_tcp(conn);
2324 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2325 	}
2326 
2327 	if (conn->conn_ops->DataDigest) {
2328 		u32 data_crc;
2329 
2330 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2331 						    cmd->write_data_done, length, padding,
2332 						    cmd->pad_bytes);
2333 
2334 		if (checksum != data_crc) {
2335 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2336 				" does not match computed 0x%08x\n", checksum,
2337 				data_crc);
2338 
2339 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2340 				pr_err("Unable to recover from"
2341 					" Immediate Data digest failure while"
2342 					" in ERL=0.\n");
2343 				iscsit_add_reject_from_cmd(
2344 						ISCSI_REASON_DATA_DIGEST_ERROR,
2345 						1, 0, buf, cmd);
2346 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2347 			} else {
2348 				iscsit_add_reject_from_cmd(
2349 						ISCSI_REASON_DATA_DIGEST_ERROR,
2350 						0, 0, buf, cmd);
2351 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2352 			}
2353 		} else {
2354 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2355 				" %u bytes of Immediate Data\n", checksum,
2356 				length);
2357 		}
2358 	}
2359 
2360 	cmd->write_data_done += length;
2361 
2362 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2363 		spin_lock_bh(&cmd->istate_lock);
2364 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2365 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2366 		spin_unlock_bh(&cmd->istate_lock);
2367 	}
2368 
2369 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2370 }
2371 
2372 /*
2373  *	Called with sess->conn_lock held.
2374  */
2375 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2376 	with active network interface */
2377 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2378 {
2379 	struct iscsi_cmd *cmd;
2380 	struct iscsi_conn *conn_p;
2381 
2382 	/*
2383 	 * Only send a Asynchronous Message on connections whos network
2384 	 * interface is still functional.
2385 	 */
2386 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2387 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2388 			iscsit_inc_conn_usage_count(conn_p);
2389 			break;
2390 		}
2391 	}
2392 
2393 	if (!conn_p)
2394 		return;
2395 
2396 	cmd = iscsit_allocate_cmd(conn_p, GFP_KERNEL);
2397 	if (!cmd) {
2398 		iscsit_dec_conn_usage_count(conn_p);
2399 		return;
2400 	}
2401 
2402 	cmd->logout_cid = conn->cid;
2403 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2404 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2405 
2406 	spin_lock_bh(&conn_p->cmd_lock);
2407 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2408 	spin_unlock_bh(&conn_p->cmd_lock);
2409 
2410 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2411 	iscsit_dec_conn_usage_count(conn_p);
2412 }
2413 
2414 static int iscsit_send_conn_drop_async_message(
2415 	struct iscsi_cmd *cmd,
2416 	struct iscsi_conn *conn)
2417 {
2418 	struct iscsi_async *hdr;
2419 
2420 	cmd->tx_size = ISCSI_HDR_LEN;
2421 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2422 
2423 	hdr			= (struct iscsi_async *) cmd->pdu;
2424 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2425 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2426 	cmd->init_task_tag	= 0xFFFFFFFF;
2427 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2428 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2429 	cmd->stat_sn		= conn->stat_sn++;
2430 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2431 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2432 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2433 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2434 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2435 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2436 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2437 
2438 	if (conn->conn_ops->HeaderDigest) {
2439 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2440 
2441 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2442 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2443 				0, NULL, (u8 *)header_digest);
2444 
2445 		cmd->tx_size += ISCSI_CRC_LEN;
2446 		pr_debug("Attaching CRC32C HeaderDigest to"
2447 			" Async Message 0x%08x\n", *header_digest);
2448 	}
2449 
2450 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2451 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2452 	cmd->iov_misc_count		= 1;
2453 
2454 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2455 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2456 			cmd->logout_cid, conn->cid);
2457 	return 0;
2458 }
2459 
2460 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2461 {
2462 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2463 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2464 		wait_for_completion_interruptible_timeout(
2465 					&conn->tx_half_close_comp,
2466 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2467 	}
2468 }
2469 
2470 static int iscsit_send_data_in(
2471 	struct iscsi_cmd *cmd,
2472 	struct iscsi_conn *conn)
2473 {
2474 	int iov_ret = 0, set_statsn = 0;
2475 	u32 iov_count = 0, tx_size = 0;
2476 	struct iscsi_datain datain;
2477 	struct iscsi_datain_req *dr;
2478 	struct iscsi_data_rsp *hdr;
2479 	struct kvec *iov;
2480 	int eodr = 0;
2481 	int ret;
2482 
2483 	memset(&datain, 0, sizeof(struct iscsi_datain));
2484 	dr = iscsit_get_datain_values(cmd, &datain);
2485 	if (!dr) {
2486 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2487 				cmd->init_task_tag);
2488 		return -1;
2489 	}
2490 
2491 	/*
2492 	 * Be paranoid and double check the logic for now.
2493 	 */
2494 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2495 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2496 			" datain.length: %u exceeds cmd->data_length: %u\n",
2497 			cmd->init_task_tag, datain.offset, datain.length,
2498 				cmd->se_cmd.data_length);
2499 		return -1;
2500 	}
2501 
2502 	spin_lock_bh(&conn->sess->session_stats_lock);
2503 	conn->sess->tx_data_octets += datain.length;
2504 	if (conn->sess->se_sess->se_node_acl) {
2505 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
2506 		conn->sess->se_sess->se_node_acl->read_bytes += datain.length;
2507 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
2508 	}
2509 	spin_unlock_bh(&conn->sess->session_stats_lock);
2510 	/*
2511 	 * Special case for successfully execution w/ both DATAIN
2512 	 * and Sense Data.
2513 	 */
2514 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2515 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2516 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2517 	else {
2518 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2519 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2520 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2521 			cmd->stat_sn = conn->stat_sn++;
2522 			set_statsn = 1;
2523 		} else if (dr->dr_complete ==
2524 				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2525 			set_statsn = 1;
2526 	}
2527 
2528 	hdr	= (struct iscsi_data_rsp *) cmd->pdu;
2529 	memset(hdr, 0, ISCSI_HDR_LEN);
2530 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2531 	hdr->flags		= datain.flags;
2532 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2533 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2534 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2535 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2536 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2537 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2538 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2539 		}
2540 	}
2541 	hton24(hdr->dlength, datain.length);
2542 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2543 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2544 				(struct scsi_lun *)&hdr->lun);
2545 	else
2546 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2547 
2548 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2549 	hdr->ttt		= (hdr->flags & ISCSI_FLAG_DATA_ACK) ?
2550 				   cpu_to_be32(cmd->targ_xfer_tag) :
2551 				   0xFFFFFFFF;
2552 	hdr->statsn		= (set_statsn) ? cpu_to_be32(cmd->stat_sn) :
2553 						0xFFFFFFFF;
2554 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2555 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2556 	hdr->datasn		= cpu_to_be32(datain.data_sn);
2557 	hdr->offset		= cpu_to_be32(datain.offset);
2558 
2559 	iov = &cmd->iov_data[0];
2560 	iov[iov_count].iov_base	= cmd->pdu;
2561 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2562 	tx_size += ISCSI_HDR_LEN;
2563 
2564 	if (conn->conn_ops->HeaderDigest) {
2565 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2566 
2567 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2568 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2569 				0, NULL, (u8 *)header_digest);
2570 
2571 		iov[0].iov_len += ISCSI_CRC_LEN;
2572 		tx_size += ISCSI_CRC_LEN;
2573 
2574 		pr_debug("Attaching CRC32 HeaderDigest"
2575 			" for DataIN PDU 0x%08x\n", *header_digest);
2576 	}
2577 
2578 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1], datain.offset, datain.length);
2579 	if (iov_ret < 0)
2580 		return -1;
2581 
2582 	iov_count += iov_ret;
2583 	tx_size += datain.length;
2584 
2585 	cmd->padding = ((-datain.length) & 3);
2586 	if (cmd->padding) {
2587 		iov[iov_count].iov_base		= cmd->pad_bytes;
2588 		iov[iov_count++].iov_len	= cmd->padding;
2589 		tx_size += cmd->padding;
2590 
2591 		pr_debug("Attaching %u padding bytes\n",
2592 				cmd->padding);
2593 	}
2594 	if (conn->conn_ops->DataDigest) {
2595 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2596 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2597 
2598 		iov[iov_count].iov_base	= &cmd->data_crc;
2599 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2600 		tx_size += ISCSI_CRC_LEN;
2601 
2602 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2603 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2604 	}
2605 
2606 	cmd->iov_data_count = iov_count;
2607 	cmd->tx_size = tx_size;
2608 
2609 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2610 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2611 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2612 		ntohl(hdr->offset), datain.length, conn->cid);
2613 
2614 	/* sendpage is preferred but can't insert markers */
2615 	if (!conn->conn_ops->IFMarker)
2616 		ret = iscsit_fe_sendpage_sg(cmd, conn);
2617 	else
2618 		ret = iscsit_send_tx_data(cmd, conn, 0);
2619 
2620 	iscsit_unmap_iovec(cmd);
2621 
2622 	if (ret < 0) {
2623 		iscsit_tx_thread_wait_for_tcp(conn);
2624 		return ret;
2625 	}
2626 
2627 	if (dr->dr_complete) {
2628 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2629 				2 : 1;
2630 		iscsit_free_datain_req(cmd, dr);
2631 	}
2632 
2633 	return eodr;
2634 }
2635 
2636 static int iscsit_send_logout_response(
2637 	struct iscsi_cmd *cmd,
2638 	struct iscsi_conn *conn)
2639 {
2640 	int niov = 0, tx_size;
2641 	struct iscsi_conn *logout_conn = NULL;
2642 	struct iscsi_conn_recovery *cr = NULL;
2643 	struct iscsi_session *sess = conn->sess;
2644 	struct kvec *iov;
2645 	struct iscsi_logout_rsp *hdr;
2646 	/*
2647 	 * The actual shutting down of Sessions and/or Connections
2648 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2649 	 * is done in scsi_logout_post_handler().
2650 	 */
2651 	switch (cmd->logout_reason) {
2652 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2653 		pr_debug("iSCSI session logout successful, setting"
2654 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2655 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2656 		break;
2657 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2658 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2659 			break;
2660 		/*
2661 		 * For CLOSECONNECTION logout requests carrying
2662 		 * a matching logout CID -> local CID, the reference
2663 		 * for the local CID will have been incremented in
2664 		 * iscsi_logout_closeconnection().
2665 		 *
2666 		 * For CLOSECONNECTION logout requests carrying
2667 		 * a different CID than the connection it arrived
2668 		 * on, the connection responding to cmd->logout_cid
2669 		 * is stopped in iscsit_logout_post_handler_diffcid().
2670 		 */
2671 
2672 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2673 			" successful.\n", cmd->logout_cid, conn->cid);
2674 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2675 		break;
2676 	case ISCSI_LOGOUT_REASON_RECOVERY:
2677 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2678 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2679 			break;
2680 		/*
2681 		 * If the connection is still active from our point of view
2682 		 * force connection recovery to occur.
2683 		 */
2684 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2685 				cmd->logout_cid);
2686 		if ((logout_conn)) {
2687 			iscsit_connection_reinstatement_rcfr(logout_conn);
2688 			iscsit_dec_conn_usage_count(logout_conn);
2689 		}
2690 
2691 		cr = iscsit_get_inactive_connection_recovery_entry(
2692 				conn->sess, cmd->logout_cid);
2693 		if (!cr) {
2694 			pr_err("Unable to locate CID: %hu for"
2695 			" REMOVECONNFORRECOVERY Logout Request.\n",
2696 				cmd->logout_cid);
2697 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2698 			break;
2699 		}
2700 
2701 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2702 
2703 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2704 			" for recovery for CID: %hu on CID: %hu successful.\n",
2705 				cmd->logout_cid, conn->cid);
2706 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2707 		break;
2708 	default:
2709 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2710 				cmd->logout_reason);
2711 		return -1;
2712 	}
2713 
2714 	tx_size = ISCSI_HDR_LEN;
2715 	hdr			= (struct iscsi_logout_rsp *)cmd->pdu;
2716 	memset(hdr, 0, ISCSI_HDR_LEN);
2717 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2718 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2719 	hdr->response		= cmd->logout_response;
2720 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2721 	cmd->stat_sn		= conn->stat_sn++;
2722 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2723 
2724 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2725 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2726 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2727 
2728 	iov = &cmd->iov_misc[0];
2729 	iov[niov].iov_base	= cmd->pdu;
2730 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2731 
2732 	if (conn->conn_ops->HeaderDigest) {
2733 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2734 
2735 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2736 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2737 				0, NULL, (u8 *)header_digest);
2738 
2739 		iov[0].iov_len += ISCSI_CRC_LEN;
2740 		tx_size += ISCSI_CRC_LEN;
2741 		pr_debug("Attaching CRC32C HeaderDigest to"
2742 			" Logout Response 0x%08x\n", *header_digest);
2743 	}
2744 	cmd->iov_misc_count = niov;
2745 	cmd->tx_size = tx_size;
2746 
2747 	pr_debug("Sending Logout Response ITT: 0x%08x StatSN:"
2748 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2749 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2750 		cmd->logout_cid, conn->cid);
2751 
2752 	return 0;
2753 }
2754 
2755 /*
2756  *	Unsolicited NOPIN, either requesting a response or not.
2757  */
2758 static int iscsit_send_unsolicited_nopin(
2759 	struct iscsi_cmd *cmd,
2760 	struct iscsi_conn *conn,
2761 	int want_response)
2762 {
2763 	int tx_size = ISCSI_HDR_LEN;
2764 	struct iscsi_nopin *hdr;
2765 	int ret;
2766 
2767 	hdr			= (struct iscsi_nopin *) cmd->pdu;
2768 	memset(hdr, 0, ISCSI_HDR_LEN);
2769 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2770 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2771 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2772 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2773 	cmd->stat_sn		= conn->stat_sn;
2774 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2775 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2776 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2777 
2778 	if (conn->conn_ops->HeaderDigest) {
2779 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2780 
2781 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2782 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2783 				0, NULL, (u8 *)header_digest);
2784 
2785 		tx_size += ISCSI_CRC_LEN;
2786 		pr_debug("Attaching CRC32C HeaderDigest to"
2787 			" NopIN 0x%08x\n", *header_digest);
2788 	}
2789 
2790 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2791 	cmd->iov_misc[0].iov_len	= tx_size;
2792 	cmd->iov_misc_count	= 1;
2793 	cmd->tx_size		= tx_size;
2794 
2795 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2796 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2797 
2798 	ret = iscsit_send_tx_data(cmd, conn, 1);
2799 	if (ret < 0) {
2800 		iscsit_tx_thread_wait_for_tcp(conn);
2801 		return ret;
2802 	}
2803 
2804 	spin_lock_bh(&cmd->istate_lock);
2805 	cmd->i_state = want_response ?
2806 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2807 	spin_unlock_bh(&cmd->istate_lock);
2808 
2809 	return 0;
2810 }
2811 
2812 static int iscsit_send_nopin_response(
2813 	struct iscsi_cmd *cmd,
2814 	struct iscsi_conn *conn)
2815 {
2816 	int niov = 0, tx_size;
2817 	u32 padding = 0;
2818 	struct kvec *iov;
2819 	struct iscsi_nopin *hdr;
2820 
2821 	tx_size = ISCSI_HDR_LEN;
2822 	hdr			= (struct iscsi_nopin *) cmd->pdu;
2823 	memset(hdr, 0, ISCSI_HDR_LEN);
2824 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2825 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2826 	hton24(hdr->dlength, cmd->buf_ptr_size);
2827 	put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2828 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2829 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2830 	cmd->stat_sn		= conn->stat_sn++;
2831 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2832 
2833 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2834 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2835 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2836 
2837 	iov = &cmd->iov_misc[0];
2838 	iov[niov].iov_base	= cmd->pdu;
2839 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2840 
2841 	if (conn->conn_ops->HeaderDigest) {
2842 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2843 
2844 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2845 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2846 				0, NULL, (u8 *)header_digest);
2847 
2848 		iov[0].iov_len += ISCSI_CRC_LEN;
2849 		tx_size += ISCSI_CRC_LEN;
2850 		pr_debug("Attaching CRC32C HeaderDigest"
2851 			" to NopIn 0x%08x\n", *header_digest);
2852 	}
2853 
2854 	/*
2855 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2856 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2857 	 */
2858 	if (cmd->buf_ptr_size) {
2859 		iov[niov].iov_base	= cmd->buf_ptr;
2860 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2861 		tx_size += cmd->buf_ptr_size;
2862 
2863 		pr_debug("Echoing back %u bytes of ping"
2864 			" data.\n", cmd->buf_ptr_size);
2865 
2866 		padding = ((-cmd->buf_ptr_size) & 3);
2867 		if (padding != 0) {
2868 			iov[niov].iov_base = &cmd->pad_bytes;
2869 			iov[niov++].iov_len = padding;
2870 			tx_size += padding;
2871 			pr_debug("Attaching %u additional"
2872 				" padding bytes.\n", padding);
2873 		}
2874 		if (conn->conn_ops->DataDigest) {
2875 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2876 				cmd->buf_ptr, cmd->buf_ptr_size,
2877 				padding, (u8 *)&cmd->pad_bytes,
2878 				(u8 *)&cmd->data_crc);
2879 
2880 			iov[niov].iov_base = &cmd->data_crc;
2881 			iov[niov++].iov_len = ISCSI_CRC_LEN;
2882 			tx_size += ISCSI_CRC_LEN;
2883 			pr_debug("Attached DataDigest for %u"
2884 				" bytes of ping data, CRC 0x%08x\n",
2885 				cmd->buf_ptr_size, cmd->data_crc);
2886 		}
2887 	}
2888 
2889 	cmd->iov_misc_count = niov;
2890 	cmd->tx_size = tx_size;
2891 
2892 	pr_debug("Sending NOPIN Response ITT: 0x%08x, TTT:"
2893 		" 0x%08x, StatSN: 0x%08x, Length %u\n", cmd->init_task_tag,
2894 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2895 
2896 	return 0;
2897 }
2898 
2899 static int iscsit_send_r2t(
2900 	struct iscsi_cmd *cmd,
2901 	struct iscsi_conn *conn)
2902 {
2903 	int tx_size = 0;
2904 	struct iscsi_r2t *r2t;
2905 	struct iscsi_r2t_rsp *hdr;
2906 	int ret;
2907 
2908 	r2t = iscsit_get_r2t_from_list(cmd);
2909 	if (!r2t)
2910 		return -1;
2911 
2912 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
2913 	memset(hdr, 0, ISCSI_HDR_LEN);
2914 	hdr->opcode		= ISCSI_OP_R2T;
2915 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2916 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2917 			(struct scsi_lun *)&hdr->lun);
2918 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2919 	spin_lock_bh(&conn->sess->ttt_lock);
2920 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
2921 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
2922 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
2923 	spin_unlock_bh(&conn->sess->ttt_lock);
2924 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
2925 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
2926 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2927 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2928 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
2929 	hdr->data_offset	= cpu_to_be32(r2t->offset);
2930 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
2931 
2932 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2933 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
2934 	tx_size += ISCSI_HDR_LEN;
2935 
2936 	if (conn->conn_ops->HeaderDigest) {
2937 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2938 
2939 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2940 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2941 				0, NULL, (u8 *)header_digest);
2942 
2943 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
2944 		tx_size += ISCSI_CRC_LEN;
2945 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
2946 			" PDU 0x%08x\n", *header_digest);
2947 	}
2948 
2949 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
2950 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
2951 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
2952 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
2953 			r2t->offset, r2t->xfer_len, conn->cid);
2954 
2955 	cmd->iov_misc_count = 1;
2956 	cmd->tx_size = tx_size;
2957 
2958 	spin_lock_bh(&cmd->r2t_lock);
2959 	r2t->sent_r2t = 1;
2960 	spin_unlock_bh(&cmd->r2t_lock);
2961 
2962 	ret = iscsit_send_tx_data(cmd, conn, 1);
2963 	if (ret < 0) {
2964 		iscsit_tx_thread_wait_for_tcp(conn);
2965 		return ret;
2966 	}
2967 
2968 	spin_lock_bh(&cmd->dataout_timeout_lock);
2969 	iscsit_start_dataout_timer(cmd, conn);
2970 	spin_unlock_bh(&cmd->dataout_timeout_lock);
2971 
2972 	return 0;
2973 }
2974 
2975 /*
2976  *	@recovery: If called from iscsi_task_reassign_complete_write() for
2977  *		connection recovery.
2978  */
2979 int iscsit_build_r2ts_for_cmd(
2980 	struct iscsi_cmd *cmd,
2981 	struct iscsi_conn *conn,
2982 	bool recovery)
2983 {
2984 	int first_r2t = 1;
2985 	u32 offset = 0, xfer_len = 0;
2986 
2987 	spin_lock_bh(&cmd->r2t_lock);
2988 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
2989 		spin_unlock_bh(&cmd->r2t_lock);
2990 		return 0;
2991 	}
2992 
2993 	if (conn->sess->sess_ops->DataSequenceInOrder &&
2994 	    !recovery)
2995 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
2996 
2997 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
2998 		if (conn->sess->sess_ops->DataSequenceInOrder) {
2999 			offset = cmd->r2t_offset;
3000 
3001 			if (first_r2t && recovery) {
3002 				int new_data_end = offset +
3003 					conn->sess->sess_ops->MaxBurstLength -
3004 					cmd->next_burst_len;
3005 
3006 				if (new_data_end > cmd->se_cmd.data_length)
3007 					xfer_len = cmd->se_cmd.data_length - offset;
3008 				else
3009 					xfer_len =
3010 						conn->sess->sess_ops->MaxBurstLength -
3011 						cmd->next_burst_len;
3012 			} else {
3013 				int new_data_end = offset +
3014 					conn->sess->sess_ops->MaxBurstLength;
3015 
3016 				if (new_data_end > cmd->se_cmd.data_length)
3017 					xfer_len = cmd->se_cmd.data_length - offset;
3018 				else
3019 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3020 			}
3021 			cmd->r2t_offset += xfer_len;
3022 
3023 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3024 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3025 		} else {
3026 			struct iscsi_seq *seq;
3027 
3028 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3029 			if (!seq) {
3030 				spin_unlock_bh(&cmd->r2t_lock);
3031 				return -1;
3032 			}
3033 
3034 			offset = seq->offset;
3035 			xfer_len = seq->xfer_len;
3036 
3037 			if (cmd->seq_send_order == cmd->seq_count)
3038 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3039 		}
3040 		cmd->outstanding_r2ts++;
3041 		first_r2t = 0;
3042 
3043 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3044 			spin_unlock_bh(&cmd->r2t_lock);
3045 			return -1;
3046 		}
3047 
3048 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3049 			break;
3050 	}
3051 	spin_unlock_bh(&cmd->r2t_lock);
3052 
3053 	return 0;
3054 }
3055 
3056 static int iscsit_send_status(
3057 	struct iscsi_cmd *cmd,
3058 	struct iscsi_conn *conn)
3059 {
3060 	u8 iov_count = 0, recovery;
3061 	u32 padding = 0, tx_size = 0;
3062 	struct iscsi_scsi_rsp *hdr;
3063 	struct kvec *iov;
3064 
3065 	recovery = (cmd->i_state != ISTATE_SEND_STATUS);
3066 	if (!recovery)
3067 		cmd->stat_sn = conn->stat_sn++;
3068 
3069 	spin_lock_bh(&conn->sess->session_stats_lock);
3070 	conn->sess->rsp_pdus++;
3071 	spin_unlock_bh(&conn->sess->session_stats_lock);
3072 
3073 	hdr			= (struct iscsi_scsi_rsp *) cmd->pdu;
3074 	memset(hdr, 0, ISCSI_HDR_LEN);
3075 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3076 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3077 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3078 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3079 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3080 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3081 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3082 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3083 	}
3084 	hdr->response		= cmd->iscsi_response;
3085 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3086 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3087 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3088 
3089 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3090 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3091 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3092 
3093 	iov = &cmd->iov_misc[0];
3094 	iov[iov_count].iov_base	= cmd->pdu;
3095 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3096 	tx_size += ISCSI_HDR_LEN;
3097 
3098 	/*
3099 	 * Attach SENSE DATA payload to iSCSI Response PDU
3100 	 */
3101 	if (cmd->se_cmd.sense_buffer &&
3102 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3103 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3104 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3105 		hton24(hdr->dlength, cmd->se_cmd.scsi_sense_length);
3106 		iov[iov_count].iov_base	= cmd->se_cmd.sense_buffer;
3107 		iov[iov_count++].iov_len =
3108 				(cmd->se_cmd.scsi_sense_length + padding);
3109 		tx_size += cmd->se_cmd.scsi_sense_length;
3110 
3111 		if (padding) {
3112 			memset(cmd->se_cmd.sense_buffer +
3113 				cmd->se_cmd.scsi_sense_length, 0, padding);
3114 			tx_size += padding;
3115 			pr_debug("Adding %u bytes of padding to"
3116 				" SENSE.\n", padding);
3117 		}
3118 
3119 		if (conn->conn_ops->DataDigest) {
3120 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3121 				cmd->se_cmd.sense_buffer,
3122 				(cmd->se_cmd.scsi_sense_length + padding),
3123 				0, NULL, (u8 *)&cmd->data_crc);
3124 
3125 			iov[iov_count].iov_base    = &cmd->data_crc;
3126 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3127 			tx_size += ISCSI_CRC_LEN;
3128 
3129 			pr_debug("Attaching CRC32 DataDigest for"
3130 				" SENSE, %u bytes CRC 0x%08x\n",
3131 				(cmd->se_cmd.scsi_sense_length + padding),
3132 				cmd->data_crc);
3133 		}
3134 
3135 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3136 				" Response PDU\n",
3137 				cmd->se_cmd.scsi_sense_length);
3138 	}
3139 
3140 	if (conn->conn_ops->HeaderDigest) {
3141 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3142 
3143 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3144 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3145 				0, NULL, (u8 *)header_digest);
3146 
3147 		iov[0].iov_len += ISCSI_CRC_LEN;
3148 		tx_size += ISCSI_CRC_LEN;
3149 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3150 				" PDU 0x%08x\n", *header_digest);
3151 	}
3152 
3153 	cmd->iov_misc_count = iov_count;
3154 	cmd->tx_size = tx_size;
3155 
3156 	pr_debug("Built %sSCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3157 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3158 		(!recovery) ? "" : "Recovery ", cmd->init_task_tag,
3159 		cmd->stat_sn, 0x00, cmd->se_cmd.scsi_status, conn->cid);
3160 
3161 	return 0;
3162 }
3163 
3164 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3165 {
3166 	switch (se_tmr->response) {
3167 	case TMR_FUNCTION_COMPLETE:
3168 		return ISCSI_TMF_RSP_COMPLETE;
3169 	case TMR_TASK_DOES_NOT_EXIST:
3170 		return ISCSI_TMF_RSP_NO_TASK;
3171 	case TMR_LUN_DOES_NOT_EXIST:
3172 		return ISCSI_TMF_RSP_NO_LUN;
3173 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3174 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3175 	case TMR_FUNCTION_AUTHORIZATION_FAILED:
3176 		return ISCSI_TMF_RSP_AUTH_FAILED;
3177 	case TMR_FUNCTION_REJECTED:
3178 	default:
3179 		return ISCSI_TMF_RSP_REJECTED;
3180 	}
3181 }
3182 
3183 static int iscsit_send_task_mgt_rsp(
3184 	struct iscsi_cmd *cmd,
3185 	struct iscsi_conn *conn)
3186 {
3187 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3188 	struct iscsi_tm_rsp *hdr;
3189 	u32 tx_size = 0;
3190 
3191 	hdr			= (struct iscsi_tm_rsp *) cmd->pdu;
3192 	memset(hdr, 0, ISCSI_HDR_LEN);
3193 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3194 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3195 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3196 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3197 	cmd->stat_sn		= conn->stat_sn++;
3198 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3199 
3200 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3201 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3202 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3203 
3204 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3205 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3206 	tx_size += ISCSI_HDR_LEN;
3207 
3208 	if (conn->conn_ops->HeaderDigest) {
3209 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3210 
3211 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3212 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3213 				0, NULL, (u8 *)header_digest);
3214 
3215 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3216 		tx_size += ISCSI_CRC_LEN;
3217 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3218 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3219 	}
3220 
3221 	cmd->iov_misc_count = 1;
3222 	cmd->tx_size = tx_size;
3223 
3224 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3225 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3226 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3227 
3228 	return 0;
3229 }
3230 
3231 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3232 {
3233 	bool ret = false;
3234 
3235 	if (np->np_sockaddr.ss_family == AF_INET6) {
3236 		const struct sockaddr_in6 sin6 = {
3237 			.sin6_addr = IN6ADDR_ANY_INIT };
3238 		struct sockaddr_in6 *sock_in6 =
3239 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3240 
3241 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3242 				sin6.sin6_addr.s6_addr, 16))
3243 			ret = true;
3244 	} else {
3245 		struct sockaddr_in * sock_in =
3246 			(struct sockaddr_in *)&np->np_sockaddr;
3247 
3248 		if (sock_in->sin_addr.s_addr == INADDR_ANY)
3249 			ret = true;
3250 	}
3251 
3252 	return ret;
3253 }
3254 
3255 #define SENDTARGETS_BUF_LIMIT 32768U
3256 
3257 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3258 {
3259 	char *payload = NULL;
3260 	struct iscsi_conn *conn = cmd->conn;
3261 	struct iscsi_portal_group *tpg;
3262 	struct iscsi_tiqn *tiqn;
3263 	struct iscsi_tpg_np *tpg_np;
3264 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3265 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3266 
3267 	buffer_len = max(conn->conn_ops->MaxRecvDataSegmentLength,
3268 			 SENDTARGETS_BUF_LIMIT);
3269 
3270 	payload = kzalloc(buffer_len, GFP_KERNEL);
3271 	if (!payload) {
3272 		pr_err("Unable to allocate memory for sendtargets"
3273 				" response.\n");
3274 		return -ENOMEM;
3275 	}
3276 
3277 	spin_lock(&tiqn_lock);
3278 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3279 		len = sprintf(buf, "TargetName=%s", tiqn->tiqn);
3280 		len += 1;
3281 
3282 		if ((len + payload_len) > buffer_len) {
3283 			spin_unlock(&tiqn->tiqn_tpg_lock);
3284 			end_of_buf = 1;
3285 			goto eob;
3286 		}
3287 		memcpy(payload + payload_len, buf, len);
3288 		payload_len += len;
3289 
3290 		spin_lock(&tiqn->tiqn_tpg_lock);
3291 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3292 
3293 			spin_lock(&tpg->tpg_state_lock);
3294 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3295 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3296 				spin_unlock(&tpg->tpg_state_lock);
3297 				continue;
3298 			}
3299 			spin_unlock(&tpg->tpg_state_lock);
3300 
3301 			spin_lock(&tpg->tpg_np_lock);
3302 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3303 						tpg_np_list) {
3304 				struct iscsi_np *np = tpg_np->tpg_np;
3305 				bool inaddr_any = iscsit_check_inaddr_any(np);
3306 
3307 				len = sprintf(buf, "TargetAddress="
3308 					"%s%s%s:%hu,%hu",
3309 					(np->np_sockaddr.ss_family == AF_INET6) ?
3310 					"[" : "", (inaddr_any == false) ?
3311 						np->np_ip : conn->local_ip,
3312 					(np->np_sockaddr.ss_family == AF_INET6) ?
3313 					"]" : "", (inaddr_any == false) ?
3314 						np->np_port : conn->local_port,
3315 					tpg->tpgt);
3316 				len += 1;
3317 
3318 				if ((len + payload_len) > buffer_len) {
3319 					spin_unlock(&tpg->tpg_np_lock);
3320 					spin_unlock(&tiqn->tiqn_tpg_lock);
3321 					end_of_buf = 1;
3322 					goto eob;
3323 				}
3324 				memcpy(payload + payload_len, buf, len);
3325 				payload_len += len;
3326 			}
3327 			spin_unlock(&tpg->tpg_np_lock);
3328 		}
3329 		spin_unlock(&tiqn->tiqn_tpg_lock);
3330 eob:
3331 		if (end_of_buf)
3332 			break;
3333 	}
3334 	spin_unlock(&tiqn_lock);
3335 
3336 	cmd->buf_ptr = payload;
3337 
3338 	return payload_len;
3339 }
3340 
3341 /*
3342  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3343  *	MaxRecvDataSegmentLength.
3344  */
3345 static int iscsit_send_text_rsp(
3346 	struct iscsi_cmd *cmd,
3347 	struct iscsi_conn *conn)
3348 {
3349 	struct iscsi_text_rsp *hdr;
3350 	struct kvec *iov;
3351 	u32 padding = 0, tx_size = 0;
3352 	int text_length, iov_count = 0;
3353 
3354 	text_length = iscsit_build_sendtargets_response(cmd);
3355 	if (text_length < 0)
3356 		return text_length;
3357 
3358 	padding = ((-text_length) & 3);
3359 	if (padding != 0) {
3360 		memset(cmd->buf_ptr + text_length, 0, padding);
3361 		pr_debug("Attaching %u additional bytes for"
3362 			" padding.\n", padding);
3363 	}
3364 
3365 	hdr			= (struct iscsi_text_rsp *) cmd->pdu;
3366 	memset(hdr, 0, ISCSI_HDR_LEN);
3367 	hdr->opcode		= ISCSI_OP_TEXT_RSP;
3368 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3369 	hton24(hdr->dlength, text_length);
3370 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3371 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
3372 	cmd->stat_sn		= conn->stat_sn++;
3373 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3374 
3375 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3376 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3377 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3378 
3379 	iov = &cmd->iov_misc[0];
3380 
3381 	iov[iov_count].iov_base = cmd->pdu;
3382 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3383 	iov[iov_count].iov_base	= cmd->buf_ptr;
3384 	iov[iov_count++].iov_len = text_length + padding;
3385 
3386 	tx_size += (ISCSI_HDR_LEN + text_length + padding);
3387 
3388 	if (conn->conn_ops->HeaderDigest) {
3389 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3390 
3391 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3392 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3393 				0, NULL, (u8 *)header_digest);
3394 
3395 		iov[0].iov_len += ISCSI_CRC_LEN;
3396 		tx_size += ISCSI_CRC_LEN;
3397 		pr_debug("Attaching CRC32 HeaderDigest for"
3398 			" Text Response PDU 0x%08x\n", *header_digest);
3399 	}
3400 
3401 	if (conn->conn_ops->DataDigest) {
3402 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3403 				cmd->buf_ptr, (text_length + padding),
3404 				0, NULL, (u8 *)&cmd->data_crc);
3405 
3406 		iov[iov_count].iov_base	= &cmd->data_crc;
3407 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3408 		tx_size	+= ISCSI_CRC_LEN;
3409 
3410 		pr_debug("Attaching DataDigest for %u bytes of text"
3411 			" data, CRC 0x%08x\n", (text_length + padding),
3412 			cmd->data_crc);
3413 	}
3414 
3415 	cmd->iov_misc_count = iov_count;
3416 	cmd->tx_size = tx_size;
3417 
3418 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3419 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3420 			text_length, conn->cid);
3421 	return 0;
3422 }
3423 
3424 static int iscsit_send_reject(
3425 	struct iscsi_cmd *cmd,
3426 	struct iscsi_conn *conn)
3427 {
3428 	u32 iov_count = 0, tx_size = 0;
3429 	struct iscsi_reject *hdr;
3430 	struct kvec *iov;
3431 
3432 	hdr			= (struct iscsi_reject *) cmd->pdu;
3433 	hdr->opcode		= ISCSI_OP_REJECT;
3434 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3435 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3436 	cmd->stat_sn		= conn->stat_sn++;
3437 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3438 	hdr->exp_cmdsn	= cpu_to_be32(conn->sess->exp_cmd_sn);
3439 	hdr->max_cmdsn	= cpu_to_be32(conn->sess->max_cmd_sn);
3440 
3441 	iov = &cmd->iov_misc[0];
3442 
3443 	iov[iov_count].iov_base = cmd->pdu;
3444 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3445 	iov[iov_count].iov_base = cmd->buf_ptr;
3446 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3447 
3448 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3449 
3450 	if (conn->conn_ops->HeaderDigest) {
3451 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3452 
3453 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3454 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3455 				0, NULL, (u8 *)header_digest);
3456 
3457 		iov[0].iov_len += ISCSI_CRC_LEN;
3458 		tx_size += ISCSI_CRC_LEN;
3459 		pr_debug("Attaching CRC32 HeaderDigest for"
3460 			" REJECT PDU 0x%08x\n", *header_digest);
3461 	}
3462 
3463 	if (conn->conn_ops->DataDigest) {
3464 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3465 				(unsigned char *)cmd->buf_ptr, ISCSI_HDR_LEN,
3466 				0, NULL, (u8 *)&cmd->data_crc);
3467 
3468 		iov[iov_count].iov_base = &cmd->data_crc;
3469 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3470 		tx_size += ISCSI_CRC_LEN;
3471 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3472 				" PDU 0x%08x\n", cmd->data_crc);
3473 	}
3474 
3475 	cmd->iov_misc_count = iov_count;
3476 	cmd->tx_size = tx_size;
3477 
3478 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3479 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3480 
3481 	return 0;
3482 }
3483 
3484 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3485 {
3486 	struct iscsi_thread_set *ts = conn->thread_set;
3487 	int ord, cpu;
3488 	/*
3489 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3490 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3491 	 *
3492 	 * Here we use thread_id to determine which CPU that this
3493 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3494 	 * execute upon.
3495 	 */
3496 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3497 	for_each_online_cpu(cpu) {
3498 		if (ord-- == 0) {
3499 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3500 			return;
3501 		}
3502 	}
3503 	/*
3504 	 * This should never be reached..
3505 	 */
3506 	dump_stack();
3507 	cpumask_setall(conn->conn_cpumask);
3508 }
3509 
3510 static inline void iscsit_thread_check_cpumask(
3511 	struct iscsi_conn *conn,
3512 	struct task_struct *p,
3513 	int mode)
3514 {
3515 	char buf[128];
3516 	/*
3517 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3518 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3519 	 */
3520 	if (mode == 1) {
3521 		if (!conn->conn_tx_reset_cpumask)
3522 			return;
3523 		conn->conn_tx_reset_cpumask = 0;
3524 	} else {
3525 		if (!conn->conn_rx_reset_cpumask)
3526 			return;
3527 		conn->conn_rx_reset_cpumask = 0;
3528 	}
3529 	/*
3530 	 * Update the CPU mask for this single kthread so that
3531 	 * both TX and RX kthreads are scheduled to run on the
3532 	 * same CPU.
3533 	 */
3534 	memset(buf, 0, 128);
3535 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3536 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3537 }
3538 
3539 static int handle_immediate_queue(struct iscsi_conn *conn)
3540 {
3541 	struct iscsi_queue_req *qr;
3542 	struct iscsi_cmd *cmd;
3543 	u8 state;
3544 	int ret;
3545 
3546 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3547 		atomic_set(&conn->check_immediate_queue, 0);
3548 		cmd = qr->cmd;
3549 		state = qr->state;
3550 		kmem_cache_free(lio_qr_cache, qr);
3551 
3552 		switch (state) {
3553 		case ISTATE_SEND_R2T:
3554 			ret = iscsit_send_r2t(cmd, conn);
3555 			if (ret < 0)
3556 				goto err;
3557 			break;
3558 		case ISTATE_REMOVE:
3559 			if (cmd->data_direction == DMA_TO_DEVICE)
3560 				iscsit_stop_dataout_timer(cmd);
3561 
3562 			spin_lock_bh(&conn->cmd_lock);
3563 			list_del(&cmd->i_conn_node);
3564 			spin_unlock_bh(&conn->cmd_lock);
3565 
3566 			iscsit_free_cmd(cmd);
3567 			continue;
3568 		case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3569 			iscsit_mod_nopin_response_timer(conn);
3570 			ret = iscsit_send_unsolicited_nopin(cmd,
3571 							    conn, 1);
3572 			if (ret < 0)
3573 				goto err;
3574 			break;
3575 		case ISTATE_SEND_NOPIN_NO_RESPONSE:
3576 			ret = iscsit_send_unsolicited_nopin(cmd,
3577 							    conn, 0);
3578 			if (ret < 0)
3579 				goto err;
3580 			break;
3581 		default:
3582 			pr_err("Unknown Opcode: 0x%02x ITT:"
3583 			       " 0x%08x, i_state: %d on CID: %hu\n",
3584 			       cmd->iscsi_opcode, cmd->init_task_tag, state,
3585 			       conn->cid);
3586 			goto err;
3587 		}
3588 	}
3589 
3590 	return 0;
3591 
3592 err:
3593 	return -1;
3594 }
3595 
3596 static int handle_response_queue(struct iscsi_conn *conn)
3597 {
3598 	struct iscsi_queue_req *qr;
3599 	struct iscsi_cmd *cmd;
3600 	u8 state;
3601 	int ret;
3602 
3603 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3604 		cmd = qr->cmd;
3605 		state = qr->state;
3606 		kmem_cache_free(lio_qr_cache, qr);
3607 
3608 check_rsp_state:
3609 		switch (state) {
3610 		case ISTATE_SEND_DATAIN:
3611 			ret = iscsit_send_data_in(cmd, conn);
3612 			if (ret < 0)
3613 				goto err;
3614 			else if (!ret)
3615 				/* more drs */
3616 				goto check_rsp_state;
3617 			else if (ret == 1) {
3618 				/* all done */
3619 				spin_lock_bh(&cmd->istate_lock);
3620 				cmd->i_state = ISTATE_SENT_STATUS;
3621 				spin_unlock_bh(&cmd->istate_lock);
3622 				continue;
3623 			} else if (ret == 2) {
3624 				/* Still must send status,
3625 				   SCF_TRANSPORT_TASK_SENSE was set */
3626 				spin_lock_bh(&cmd->istate_lock);
3627 				cmd->i_state = ISTATE_SEND_STATUS;
3628 				spin_unlock_bh(&cmd->istate_lock);
3629 				state = ISTATE_SEND_STATUS;
3630 				goto check_rsp_state;
3631 			}
3632 
3633 			break;
3634 		case ISTATE_SEND_STATUS:
3635 		case ISTATE_SEND_STATUS_RECOVERY:
3636 			ret = iscsit_send_status(cmd, conn);
3637 			break;
3638 		case ISTATE_SEND_LOGOUTRSP:
3639 			ret = iscsit_send_logout_response(cmd, conn);
3640 			break;
3641 		case ISTATE_SEND_ASYNCMSG:
3642 			ret = iscsit_send_conn_drop_async_message(
3643 				cmd, conn);
3644 			break;
3645 		case ISTATE_SEND_NOPIN:
3646 			ret = iscsit_send_nopin_response(cmd, conn);
3647 			break;
3648 		case ISTATE_SEND_REJECT:
3649 			ret = iscsit_send_reject(cmd, conn);
3650 			break;
3651 		case ISTATE_SEND_TASKMGTRSP:
3652 			ret = iscsit_send_task_mgt_rsp(cmd, conn);
3653 			if (ret != 0)
3654 				break;
3655 			ret = iscsit_tmr_post_handler(cmd, conn);
3656 			if (ret != 0)
3657 				iscsit_fall_back_to_erl0(conn->sess);
3658 			break;
3659 		case ISTATE_SEND_TEXTRSP:
3660 			ret = iscsit_send_text_rsp(cmd, conn);
3661 			break;
3662 		default:
3663 			pr_err("Unknown Opcode: 0x%02x ITT:"
3664 			       " 0x%08x, i_state: %d on CID: %hu\n",
3665 			       cmd->iscsi_opcode, cmd->init_task_tag,
3666 			       state, conn->cid);
3667 			goto err;
3668 		}
3669 		if (ret < 0)
3670 			goto err;
3671 
3672 		if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3673 			iscsit_tx_thread_wait_for_tcp(conn);
3674 			iscsit_unmap_iovec(cmd);
3675 			goto err;
3676 		}
3677 		iscsit_unmap_iovec(cmd);
3678 
3679 		switch (state) {
3680 		case ISTATE_SEND_LOGOUTRSP:
3681 			if (!iscsit_logout_post_handler(cmd, conn))
3682 				goto restart;
3683 			/* fall through */
3684 		case ISTATE_SEND_STATUS:
3685 		case ISTATE_SEND_ASYNCMSG:
3686 		case ISTATE_SEND_NOPIN:
3687 		case ISTATE_SEND_STATUS_RECOVERY:
3688 		case ISTATE_SEND_TEXTRSP:
3689 		case ISTATE_SEND_TASKMGTRSP:
3690 			spin_lock_bh(&cmd->istate_lock);
3691 			cmd->i_state = ISTATE_SENT_STATUS;
3692 			spin_unlock_bh(&cmd->istate_lock);
3693 			break;
3694 		case ISTATE_SEND_REJECT:
3695 			if (cmd->cmd_flags & ICF_REJECT_FAIL_CONN) {
3696 				cmd->cmd_flags &= ~ICF_REJECT_FAIL_CONN;
3697 				complete(&cmd->reject_comp);
3698 				goto err;
3699 			}
3700 			complete(&cmd->reject_comp);
3701 			break;
3702 		default:
3703 			pr_err("Unknown Opcode: 0x%02x ITT:"
3704 			       " 0x%08x, i_state: %d on CID: %hu\n",
3705 			       cmd->iscsi_opcode, cmd->init_task_tag,
3706 			       cmd->i_state, conn->cid);
3707 			goto err;
3708 		}
3709 
3710 		if (atomic_read(&conn->check_immediate_queue))
3711 			break;
3712 	}
3713 
3714 	return 0;
3715 
3716 err:
3717 	return -1;
3718 restart:
3719 	return -EAGAIN;
3720 }
3721 
3722 int iscsi_target_tx_thread(void *arg)
3723 {
3724 	int ret = 0;
3725 	struct iscsi_conn *conn;
3726 	struct iscsi_thread_set *ts = arg;
3727 	/*
3728 	 * Allow ourselves to be interrupted by SIGINT so that a
3729 	 * connection recovery / failure event can be triggered externally.
3730 	 */
3731 	allow_signal(SIGINT);
3732 
3733 restart:
3734 	conn = iscsi_tx_thread_pre_handler(ts);
3735 	if (!conn)
3736 		goto out;
3737 
3738 	ret = 0;
3739 
3740 	while (!kthread_should_stop()) {
3741 		/*
3742 		 * Ensure that both TX and RX per connection kthreads
3743 		 * are scheduled to run on the same CPU.
3744 		 */
3745 		iscsit_thread_check_cpumask(conn, current, 1);
3746 
3747 		schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
3748 
3749 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3750 		     signal_pending(current))
3751 			goto transport_err;
3752 
3753 		ret = handle_immediate_queue(conn);
3754 		if (ret < 0)
3755 			goto transport_err;
3756 
3757 		ret = handle_response_queue(conn);
3758 		if (ret == -EAGAIN)
3759 			goto restart;
3760 		else if (ret < 0)
3761 			goto transport_err;
3762 	}
3763 
3764 transport_err:
3765 	iscsit_take_action_for_connection_exit(conn);
3766 	goto restart;
3767 out:
3768 	return 0;
3769 }
3770 
3771 int iscsi_target_rx_thread(void *arg)
3772 {
3773 	int ret;
3774 	u8 buffer[ISCSI_HDR_LEN], opcode;
3775 	u32 checksum = 0, digest = 0;
3776 	struct iscsi_conn *conn = NULL;
3777 	struct iscsi_thread_set *ts = arg;
3778 	struct kvec iov;
3779 	/*
3780 	 * Allow ourselves to be interrupted by SIGINT so that a
3781 	 * connection recovery / failure event can be triggered externally.
3782 	 */
3783 	allow_signal(SIGINT);
3784 
3785 restart:
3786 	conn = iscsi_rx_thread_pre_handler(ts);
3787 	if (!conn)
3788 		goto out;
3789 
3790 	while (!kthread_should_stop()) {
3791 		/*
3792 		 * Ensure that both TX and RX per connection kthreads
3793 		 * are scheduled to run on the same CPU.
3794 		 */
3795 		iscsit_thread_check_cpumask(conn, current, 0);
3796 
3797 		memset(buffer, 0, ISCSI_HDR_LEN);
3798 		memset(&iov, 0, sizeof(struct kvec));
3799 
3800 		iov.iov_base	= buffer;
3801 		iov.iov_len	= ISCSI_HDR_LEN;
3802 
3803 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
3804 		if (ret != ISCSI_HDR_LEN) {
3805 			iscsit_rx_thread_wait_for_tcp(conn);
3806 			goto transport_err;
3807 		}
3808 
3809 		/*
3810 		 * Set conn->bad_hdr for use with REJECT PDUs.
3811 		 */
3812 		memcpy(&conn->bad_hdr, &buffer, ISCSI_HDR_LEN);
3813 
3814 		if (conn->conn_ops->HeaderDigest) {
3815 			iov.iov_base	= &digest;
3816 			iov.iov_len	= ISCSI_CRC_LEN;
3817 
3818 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
3819 			if (ret != ISCSI_CRC_LEN) {
3820 				iscsit_rx_thread_wait_for_tcp(conn);
3821 				goto transport_err;
3822 			}
3823 
3824 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
3825 					buffer, ISCSI_HDR_LEN,
3826 					0, NULL, (u8 *)&checksum);
3827 
3828 			if (digest != checksum) {
3829 				pr_err("HeaderDigest CRC32C failed,"
3830 					" received 0x%08x, computed 0x%08x\n",
3831 					digest, checksum);
3832 				/*
3833 				 * Set the PDU to 0xff so it will intentionally
3834 				 * hit default in the switch below.
3835 				 */
3836 				memset(buffer, 0xff, ISCSI_HDR_LEN);
3837 				spin_lock_bh(&conn->sess->session_stats_lock);
3838 				conn->sess->conn_digest_errors++;
3839 				spin_unlock_bh(&conn->sess->session_stats_lock);
3840 			} else {
3841 				pr_debug("Got HeaderDigest CRC32C"
3842 						" 0x%08x\n", checksum);
3843 			}
3844 		}
3845 
3846 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
3847 			goto transport_err;
3848 
3849 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
3850 
3851 		if (conn->sess->sess_ops->SessionType &&
3852 		   ((!(opcode & ISCSI_OP_TEXT)) ||
3853 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
3854 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
3855 			" while in Discovery Session, rejecting.\n", opcode);
3856 			iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
3857 					buffer, conn);
3858 			goto transport_err;
3859 		}
3860 
3861 		switch (opcode) {
3862 		case ISCSI_OP_SCSI_CMD:
3863 			if (iscsit_handle_scsi_cmd(conn, buffer) < 0)
3864 				goto transport_err;
3865 			break;
3866 		case ISCSI_OP_SCSI_DATA_OUT:
3867 			if (iscsit_handle_data_out(conn, buffer) < 0)
3868 				goto transport_err;
3869 			break;
3870 		case ISCSI_OP_NOOP_OUT:
3871 			if (iscsit_handle_nop_out(conn, buffer) < 0)
3872 				goto transport_err;
3873 			break;
3874 		case ISCSI_OP_SCSI_TMFUNC:
3875 			if (iscsit_handle_task_mgt_cmd(conn, buffer) < 0)
3876 				goto transport_err;
3877 			break;
3878 		case ISCSI_OP_TEXT:
3879 			if (iscsit_handle_text_cmd(conn, buffer) < 0)
3880 				goto transport_err;
3881 			break;
3882 		case ISCSI_OP_LOGOUT:
3883 			ret = iscsit_handle_logout_cmd(conn, buffer);
3884 			if (ret > 0) {
3885 				wait_for_completion_timeout(&conn->conn_logout_comp,
3886 						SECONDS_FOR_LOGOUT_COMP * HZ);
3887 				goto transport_err;
3888 			} else if (ret < 0)
3889 				goto transport_err;
3890 			break;
3891 		case ISCSI_OP_SNACK:
3892 			if (iscsit_handle_snack(conn, buffer) < 0)
3893 				goto transport_err;
3894 			break;
3895 		default:
3896 			pr_err("Got unknown iSCSI OpCode: 0x%02x\n",
3897 					opcode);
3898 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3899 				pr_err("Cannot recover from unknown"
3900 				" opcode while ERL=0, closing iSCSI connection"
3901 				".\n");
3902 				goto transport_err;
3903 			}
3904 			if (!conn->conn_ops->OFMarker) {
3905 				pr_err("Unable to recover from unknown"
3906 				" opcode while OFMarker=No, closing iSCSI"
3907 					" connection.\n");
3908 				goto transport_err;
3909 			}
3910 			if (iscsit_recover_from_unknown_opcode(conn) < 0) {
3911 				pr_err("Unable to recover from unknown"
3912 					" opcode, closing iSCSI connection.\n");
3913 				goto transport_err;
3914 			}
3915 			break;
3916 		}
3917 	}
3918 
3919 transport_err:
3920 	if (!signal_pending(current))
3921 		atomic_set(&conn->transport_failed, 1);
3922 	iscsit_take_action_for_connection_exit(conn);
3923 	goto restart;
3924 out:
3925 	return 0;
3926 }
3927 
3928 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
3929 {
3930 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
3931 	struct iscsi_session *sess = conn->sess;
3932 	/*
3933 	 * We expect this function to only ever be called from either RX or TX
3934 	 * thread context via iscsit_close_connection() once the other context
3935 	 * has been reset -> returned sleeping pre-handler state.
3936 	 */
3937 	spin_lock_bh(&conn->cmd_lock);
3938 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
3939 
3940 		list_del(&cmd->i_conn_node);
3941 		spin_unlock_bh(&conn->cmd_lock);
3942 
3943 		iscsit_increment_maxcmdsn(cmd, sess);
3944 
3945 		iscsit_free_cmd(cmd);
3946 
3947 		spin_lock_bh(&conn->cmd_lock);
3948 	}
3949 	spin_unlock_bh(&conn->cmd_lock);
3950 }
3951 
3952 static void iscsit_stop_timers_for_cmds(
3953 	struct iscsi_conn *conn)
3954 {
3955 	struct iscsi_cmd *cmd;
3956 
3957 	spin_lock_bh(&conn->cmd_lock);
3958 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
3959 		if (cmd->data_direction == DMA_TO_DEVICE)
3960 			iscsit_stop_dataout_timer(cmd);
3961 	}
3962 	spin_unlock_bh(&conn->cmd_lock);
3963 }
3964 
3965 int iscsit_close_connection(
3966 	struct iscsi_conn *conn)
3967 {
3968 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
3969 	struct iscsi_session	*sess = conn->sess;
3970 
3971 	pr_debug("Closing iSCSI connection CID %hu on SID:"
3972 		" %u\n", conn->cid, sess->sid);
3973 	/*
3974 	 * Always up conn_logout_comp just in case the RX Thread is sleeping
3975 	 * and the logout response never got sent because the connection
3976 	 * failed.
3977 	 */
3978 	complete(&conn->conn_logout_comp);
3979 
3980 	iscsi_release_thread_set(conn);
3981 
3982 	iscsit_stop_timers_for_cmds(conn);
3983 	iscsit_stop_nopin_response_timer(conn);
3984 	iscsit_stop_nopin_timer(conn);
3985 	iscsit_free_queue_reqs_for_conn(conn);
3986 
3987 	/*
3988 	 * During Connection recovery drop unacknowledged out of order
3989 	 * commands for this connection, and prepare the other commands
3990 	 * for realligence.
3991 	 *
3992 	 * During normal operation clear the out of order commands (but
3993 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
3994 	 * struct iscsi_cmds.
3995 	 */
3996 	if (atomic_read(&conn->connection_recovery)) {
3997 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
3998 		iscsit_prepare_cmds_for_realligance(conn);
3999 	} else {
4000 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4001 		iscsit_release_commands_from_conn(conn);
4002 	}
4003 
4004 	/*
4005 	 * Handle decrementing session or connection usage count if
4006 	 * a logout response was not able to be sent because the
4007 	 * connection failed.  Fall back to Session Recovery here.
4008 	 */
4009 	if (atomic_read(&conn->conn_logout_remove)) {
4010 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4011 			iscsit_dec_conn_usage_count(conn);
4012 			iscsit_dec_session_usage_count(sess);
4013 		}
4014 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4015 			iscsit_dec_conn_usage_count(conn);
4016 
4017 		atomic_set(&conn->conn_logout_remove, 0);
4018 		atomic_set(&sess->session_reinstatement, 0);
4019 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4020 	}
4021 
4022 	spin_lock_bh(&sess->conn_lock);
4023 	list_del(&conn->conn_list);
4024 
4025 	/*
4026 	 * Attempt to let the Initiator know this connection failed by
4027 	 * sending an Connection Dropped Async Message on another
4028 	 * active connection.
4029 	 */
4030 	if (atomic_read(&conn->connection_recovery))
4031 		iscsit_build_conn_drop_async_message(conn);
4032 
4033 	spin_unlock_bh(&sess->conn_lock);
4034 
4035 	/*
4036 	 * If connection reinstatement is being performed on this connection,
4037 	 * up the connection reinstatement semaphore that is being blocked on
4038 	 * in iscsit_cause_connection_reinstatement().
4039 	 */
4040 	spin_lock_bh(&conn->state_lock);
4041 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4042 		spin_unlock_bh(&conn->state_lock);
4043 		complete(&conn->conn_wait_comp);
4044 		wait_for_completion(&conn->conn_post_wait_comp);
4045 		spin_lock_bh(&conn->state_lock);
4046 	}
4047 
4048 	/*
4049 	 * If connection reinstatement is being performed on this connection
4050 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4051 	 * connection wait rcfr semaphore that is being blocked on
4052 	 * an iscsit_connection_reinstatement_rcfr().
4053 	 */
4054 	if (atomic_read(&conn->connection_wait_rcfr)) {
4055 		spin_unlock_bh(&conn->state_lock);
4056 		complete(&conn->conn_wait_rcfr_comp);
4057 		wait_for_completion(&conn->conn_post_wait_comp);
4058 		spin_lock_bh(&conn->state_lock);
4059 	}
4060 	atomic_set(&conn->connection_reinstatement, 1);
4061 	spin_unlock_bh(&conn->state_lock);
4062 
4063 	/*
4064 	 * If any other processes are accessing this connection pointer we
4065 	 * must wait until they have completed.
4066 	 */
4067 	iscsit_check_conn_usage_count(conn);
4068 
4069 	if (conn->conn_rx_hash.tfm)
4070 		crypto_free_hash(conn->conn_rx_hash.tfm);
4071 	if (conn->conn_tx_hash.tfm)
4072 		crypto_free_hash(conn->conn_tx_hash.tfm);
4073 
4074 	if (conn->conn_cpumask)
4075 		free_cpumask_var(conn->conn_cpumask);
4076 
4077 	kfree(conn->conn_ops);
4078 	conn->conn_ops = NULL;
4079 
4080 	if (conn->sock) {
4081 		if (conn->conn_flags & CONNFLAG_SCTP_STRUCT_FILE) {
4082 			kfree(conn->sock->file);
4083 			conn->sock->file = NULL;
4084 		}
4085 		sock_release(conn->sock);
4086 	}
4087 	conn->thread_set = NULL;
4088 
4089 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4090 	conn->conn_state = TARG_CONN_STATE_FREE;
4091 	kfree(conn);
4092 
4093 	spin_lock_bh(&sess->conn_lock);
4094 	atomic_dec(&sess->nconn);
4095 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4096 		" %s\n", atomic_read(&sess->nconn),
4097 		sess->sess_ops->InitiatorName);
4098 	/*
4099 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4100 	 * Session that they all fail.
4101 	 */
4102 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4103 	     !atomic_read(&sess->session_logout))
4104 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4105 
4106 	/*
4107 	 * If this was not the last connection in the session, and we are
4108 	 * performing session reinstatement or falling back to ERL=0, call
4109 	 * iscsit_stop_session() without sleeping to shutdown the other
4110 	 * active connections.
4111 	 */
4112 	if (atomic_read(&sess->nconn)) {
4113 		if (!atomic_read(&sess->session_reinstatement) &&
4114 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4115 			spin_unlock_bh(&sess->conn_lock);
4116 			return 0;
4117 		}
4118 		if (!atomic_read(&sess->session_stop_active)) {
4119 			atomic_set(&sess->session_stop_active, 1);
4120 			spin_unlock_bh(&sess->conn_lock);
4121 			iscsit_stop_session(sess, 0, 0);
4122 			return 0;
4123 		}
4124 		spin_unlock_bh(&sess->conn_lock);
4125 		return 0;
4126 	}
4127 
4128 	/*
4129 	 * If this was the last connection in the session and one of the
4130 	 * following is occurring:
4131 	 *
4132 	 * Session Reinstatement is not being performed, and are falling back
4133 	 * to ERL=0 call iscsit_close_session().
4134 	 *
4135 	 * Session Logout was requested.  iscsit_close_session() will be called
4136 	 * elsewhere.
4137 	 *
4138 	 * Session Continuation is not being performed, start the Time2Retain
4139 	 * handler and check if sleep_on_sess_wait_sem is active.
4140 	 */
4141 	if (!atomic_read(&sess->session_reinstatement) &&
4142 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4143 		spin_unlock_bh(&sess->conn_lock);
4144 		target_put_session(sess->se_sess);
4145 
4146 		return 0;
4147 	} else if (atomic_read(&sess->session_logout)) {
4148 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4149 		sess->session_state = TARG_SESS_STATE_FREE;
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 	} else {
4157 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4158 		sess->session_state = TARG_SESS_STATE_FAILED;
4159 
4160 		if (!atomic_read(&sess->session_continuation)) {
4161 			spin_unlock_bh(&sess->conn_lock);
4162 			iscsit_start_time2retain_handler(sess);
4163 		} else
4164 			spin_unlock_bh(&sess->conn_lock);
4165 
4166 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4167 			complete(&sess->session_wait_comp);
4168 
4169 		return 0;
4170 	}
4171 	spin_unlock_bh(&sess->conn_lock);
4172 
4173 	return 0;
4174 }
4175 
4176 int iscsit_close_session(struct iscsi_session *sess)
4177 {
4178 	struct iscsi_portal_group *tpg = ISCSI_TPG_S(sess);
4179 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4180 
4181 	if (atomic_read(&sess->nconn)) {
4182 		pr_err("%d connection(s) still exist for iSCSI session"
4183 			" to %s\n", atomic_read(&sess->nconn),
4184 			sess->sess_ops->InitiatorName);
4185 		BUG();
4186 	}
4187 
4188 	spin_lock_bh(&se_tpg->session_lock);
4189 	atomic_set(&sess->session_logout, 1);
4190 	atomic_set(&sess->session_reinstatement, 1);
4191 	iscsit_stop_time2retain_timer(sess);
4192 	spin_unlock_bh(&se_tpg->session_lock);
4193 
4194 	/*
4195 	 * transport_deregister_session_configfs() will clear the
4196 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4197 	 * can be setting it again with __transport_register_session() in
4198 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4199 	 * completes in iscsi_np context.
4200 	 */
4201 	transport_deregister_session_configfs(sess->se_sess);
4202 
4203 	/*
4204 	 * If any other processes are accessing this session pointer we must
4205 	 * wait until they have completed.  If we are in an interrupt (the
4206 	 * time2retain handler) and contain and active session usage count we
4207 	 * restart the timer and exit.
4208 	 */
4209 	if (!in_interrupt()) {
4210 		if (iscsit_check_session_usage_count(sess) == 1)
4211 			iscsit_stop_session(sess, 1, 1);
4212 	} else {
4213 		if (iscsit_check_session_usage_count(sess) == 2) {
4214 			atomic_set(&sess->session_logout, 0);
4215 			iscsit_start_time2retain_handler(sess);
4216 			return 0;
4217 		}
4218 	}
4219 
4220 	transport_deregister_session(sess->se_sess);
4221 
4222 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4223 		iscsit_free_connection_recovery_entires(sess);
4224 
4225 	iscsit_free_all_ooo_cmdsns(sess);
4226 
4227 	spin_lock_bh(&se_tpg->session_lock);
4228 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4229 	sess->session_state = TARG_SESS_STATE_FREE;
4230 	pr_debug("Released iSCSI session from node: %s\n",
4231 			sess->sess_ops->InitiatorName);
4232 	tpg->nsessions--;
4233 	if (tpg->tpg_tiqn)
4234 		tpg->tpg_tiqn->tiqn_nsessions--;
4235 
4236 	pr_debug("Decremented number of active iSCSI Sessions on"
4237 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4238 
4239 	spin_lock(&sess_idr_lock);
4240 	idr_remove(&sess_idr, sess->session_index);
4241 	spin_unlock(&sess_idr_lock);
4242 
4243 	kfree(sess->sess_ops);
4244 	sess->sess_ops = NULL;
4245 	spin_unlock_bh(&se_tpg->session_lock);
4246 
4247 	kfree(sess);
4248 	return 0;
4249 }
4250 
4251 static void iscsit_logout_post_handler_closesession(
4252 	struct iscsi_conn *conn)
4253 {
4254 	struct iscsi_session *sess = conn->sess;
4255 
4256 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4257 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4258 
4259 	atomic_set(&conn->conn_logout_remove, 0);
4260 	complete(&conn->conn_logout_comp);
4261 
4262 	iscsit_dec_conn_usage_count(conn);
4263 	iscsit_stop_session(sess, 1, 1);
4264 	iscsit_dec_session_usage_count(sess);
4265 	target_put_session(sess->se_sess);
4266 }
4267 
4268 static void iscsit_logout_post_handler_samecid(
4269 	struct iscsi_conn *conn)
4270 {
4271 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4272 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4273 
4274 	atomic_set(&conn->conn_logout_remove, 0);
4275 	complete(&conn->conn_logout_comp);
4276 
4277 	iscsit_cause_connection_reinstatement(conn, 1);
4278 	iscsit_dec_conn_usage_count(conn);
4279 }
4280 
4281 static void iscsit_logout_post_handler_diffcid(
4282 	struct iscsi_conn *conn,
4283 	u16 cid)
4284 {
4285 	struct iscsi_conn *l_conn;
4286 	struct iscsi_session *sess = conn->sess;
4287 
4288 	if (!sess)
4289 		return;
4290 
4291 	spin_lock_bh(&sess->conn_lock);
4292 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4293 		if (l_conn->cid == cid) {
4294 			iscsit_inc_conn_usage_count(l_conn);
4295 			break;
4296 		}
4297 	}
4298 	spin_unlock_bh(&sess->conn_lock);
4299 
4300 	if (!l_conn)
4301 		return;
4302 
4303 	if (l_conn->sock)
4304 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4305 
4306 	spin_lock_bh(&l_conn->state_lock);
4307 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4308 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4309 	spin_unlock_bh(&l_conn->state_lock);
4310 
4311 	iscsit_cause_connection_reinstatement(l_conn, 1);
4312 	iscsit_dec_conn_usage_count(l_conn);
4313 }
4314 
4315 /*
4316  *	Return of 0 causes the TX thread to restart.
4317  */
4318 static int iscsit_logout_post_handler(
4319 	struct iscsi_cmd *cmd,
4320 	struct iscsi_conn *conn)
4321 {
4322 	int ret = 0;
4323 
4324 	switch (cmd->logout_reason) {
4325 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4326 		switch (cmd->logout_response) {
4327 		case ISCSI_LOGOUT_SUCCESS:
4328 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4329 		default:
4330 			iscsit_logout_post_handler_closesession(conn);
4331 			break;
4332 		}
4333 		ret = 0;
4334 		break;
4335 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4336 		if (conn->cid == cmd->logout_cid) {
4337 			switch (cmd->logout_response) {
4338 			case ISCSI_LOGOUT_SUCCESS:
4339 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4340 			default:
4341 				iscsit_logout_post_handler_samecid(conn);
4342 				break;
4343 			}
4344 			ret = 0;
4345 		} else {
4346 			switch (cmd->logout_response) {
4347 			case ISCSI_LOGOUT_SUCCESS:
4348 				iscsit_logout_post_handler_diffcid(conn,
4349 					cmd->logout_cid);
4350 				break;
4351 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4352 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4353 			default:
4354 				break;
4355 			}
4356 			ret = 1;
4357 		}
4358 		break;
4359 	case ISCSI_LOGOUT_REASON_RECOVERY:
4360 		switch (cmd->logout_response) {
4361 		case ISCSI_LOGOUT_SUCCESS:
4362 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4363 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4364 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4365 		default:
4366 			break;
4367 		}
4368 		ret = 1;
4369 		break;
4370 	default:
4371 		break;
4372 
4373 	}
4374 	return ret;
4375 }
4376 
4377 void iscsit_fail_session(struct iscsi_session *sess)
4378 {
4379 	struct iscsi_conn *conn;
4380 
4381 	spin_lock_bh(&sess->conn_lock);
4382 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4383 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4384 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4385 	}
4386 	spin_unlock_bh(&sess->conn_lock);
4387 
4388 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4389 	sess->session_state = TARG_SESS_STATE_FAILED;
4390 }
4391 
4392 int iscsit_free_session(struct iscsi_session *sess)
4393 {
4394 	u16 conn_count = atomic_read(&sess->nconn);
4395 	struct iscsi_conn *conn, *conn_tmp = NULL;
4396 	int is_last;
4397 
4398 	spin_lock_bh(&sess->conn_lock);
4399 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4400 
4401 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4402 			conn_list) {
4403 		if (conn_count == 0)
4404 			break;
4405 
4406 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4407 			is_last = 1;
4408 		} else {
4409 			iscsit_inc_conn_usage_count(conn_tmp);
4410 			is_last = 0;
4411 		}
4412 		iscsit_inc_conn_usage_count(conn);
4413 
4414 		spin_unlock_bh(&sess->conn_lock);
4415 		iscsit_cause_connection_reinstatement(conn, 1);
4416 		spin_lock_bh(&sess->conn_lock);
4417 
4418 		iscsit_dec_conn_usage_count(conn);
4419 		if (is_last == 0)
4420 			iscsit_dec_conn_usage_count(conn_tmp);
4421 
4422 		conn_count--;
4423 	}
4424 
4425 	if (atomic_read(&sess->nconn)) {
4426 		spin_unlock_bh(&sess->conn_lock);
4427 		wait_for_completion(&sess->session_wait_comp);
4428 	} else
4429 		spin_unlock_bh(&sess->conn_lock);
4430 
4431 	target_put_session(sess->se_sess);
4432 	return 0;
4433 }
4434 
4435 void iscsit_stop_session(
4436 	struct iscsi_session *sess,
4437 	int session_sleep,
4438 	int connection_sleep)
4439 {
4440 	u16 conn_count = atomic_read(&sess->nconn);
4441 	struct iscsi_conn *conn, *conn_tmp = NULL;
4442 	int is_last;
4443 
4444 	spin_lock_bh(&sess->conn_lock);
4445 	if (session_sleep)
4446 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4447 
4448 	if (connection_sleep) {
4449 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4450 				conn_list) {
4451 			if (conn_count == 0)
4452 				break;
4453 
4454 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4455 				is_last = 1;
4456 			} else {
4457 				iscsit_inc_conn_usage_count(conn_tmp);
4458 				is_last = 0;
4459 			}
4460 			iscsit_inc_conn_usage_count(conn);
4461 
4462 			spin_unlock_bh(&sess->conn_lock);
4463 			iscsit_cause_connection_reinstatement(conn, 1);
4464 			spin_lock_bh(&sess->conn_lock);
4465 
4466 			iscsit_dec_conn_usage_count(conn);
4467 			if (is_last == 0)
4468 				iscsit_dec_conn_usage_count(conn_tmp);
4469 			conn_count--;
4470 		}
4471 	} else {
4472 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4473 			iscsit_cause_connection_reinstatement(conn, 0);
4474 	}
4475 
4476 	if (session_sleep && atomic_read(&sess->nconn)) {
4477 		spin_unlock_bh(&sess->conn_lock);
4478 		wait_for_completion(&sess->session_wait_comp);
4479 	} else
4480 		spin_unlock_bh(&sess->conn_lock);
4481 }
4482 
4483 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4484 {
4485 	struct iscsi_session *sess;
4486 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4487 	struct se_session *se_sess, *se_sess_tmp;
4488 	int session_count = 0;
4489 
4490 	spin_lock_bh(&se_tpg->session_lock);
4491 	if (tpg->nsessions && !force) {
4492 		spin_unlock_bh(&se_tpg->session_lock);
4493 		return -1;
4494 	}
4495 
4496 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4497 			sess_list) {
4498 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4499 
4500 		spin_lock(&sess->conn_lock);
4501 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4502 		    atomic_read(&sess->session_logout) ||
4503 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4504 			spin_unlock(&sess->conn_lock);
4505 			continue;
4506 		}
4507 		atomic_set(&sess->session_reinstatement, 1);
4508 		spin_unlock(&sess->conn_lock);
4509 		spin_unlock_bh(&se_tpg->session_lock);
4510 
4511 		iscsit_free_session(sess);
4512 		spin_lock_bh(&se_tpg->session_lock);
4513 
4514 		session_count++;
4515 	}
4516 	spin_unlock_bh(&se_tpg->session_lock);
4517 
4518 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4519 			" Group: %hu\n", session_count, tpg->tpgt);
4520 	return 0;
4521 }
4522 
4523 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4524 MODULE_VERSION("4.1.x");
4525 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4526 MODULE_LICENSE("GPL");
4527 
4528 module_init(iscsi_target_init_module);
4529 module_exit(iscsi_target_cleanup_module);
4530