xref: /linux/drivers/target/iscsi/iscsi_target.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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 <asm/unaligned.h>
27 #include <scsi/scsi_device.h>
28 #include <scsi/iscsi_proto.h>
29 #include <target/target_core_base.h>
30 #include <target/target_core_fabric.h>
31 
32 #include "iscsi_target_core.h"
33 #include "iscsi_target_parameters.h"
34 #include "iscsi_target_seq_pdu_list.h"
35 #include "iscsi_target_tq.h"
36 #include "iscsi_target_configfs.h"
37 #include "iscsi_target_datain_values.h"
38 #include "iscsi_target_erl0.h"
39 #include "iscsi_target_erl1.h"
40 #include "iscsi_target_erl2.h"
41 #include "iscsi_target_login.h"
42 #include "iscsi_target_tmr.h"
43 #include "iscsi_target_tpg.h"
44 #include "iscsi_target_util.h"
45 #include "iscsi_target.h"
46 #include "iscsi_target_device.h"
47 #include "iscsi_target_stat.h"
48 
49 static LIST_HEAD(g_tiqn_list);
50 static LIST_HEAD(g_np_list);
51 static DEFINE_SPINLOCK(tiqn_lock);
52 static DEFINE_SPINLOCK(np_lock);
53 
54 static struct idr tiqn_idr;
55 struct idr sess_idr;
56 struct mutex auth_id_lock;
57 spinlock_t sess_idr_lock;
58 
59 struct iscsit_global *iscsit_global;
60 
61 struct kmem_cache *lio_cmd_cache;
62 struct kmem_cache *lio_qr_cache;
63 struct kmem_cache *lio_dr_cache;
64 struct kmem_cache *lio_ooo_cache;
65 struct kmem_cache *lio_r2t_cache;
66 
67 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
68 			unsigned char *buf, u32);
69 static int iscsit_logout_post_handler(struct iscsi_cmd *, struct iscsi_conn *);
70 
71 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
72 {
73 	struct iscsi_tiqn *tiqn = NULL;
74 
75 	spin_lock(&tiqn_lock);
76 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
77 		if (!strcmp(tiqn->tiqn, buf)) {
78 
79 			spin_lock(&tiqn->tiqn_state_lock);
80 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
81 				tiqn->tiqn_access_count++;
82 				spin_unlock(&tiqn->tiqn_state_lock);
83 				spin_unlock(&tiqn_lock);
84 				return tiqn;
85 			}
86 			spin_unlock(&tiqn->tiqn_state_lock);
87 		}
88 	}
89 	spin_unlock(&tiqn_lock);
90 
91 	return NULL;
92 }
93 
94 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
95 {
96 	spin_lock(&tiqn->tiqn_state_lock);
97 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
98 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
99 		spin_unlock(&tiqn->tiqn_state_lock);
100 		return 0;
101 	}
102 	spin_unlock(&tiqn->tiqn_state_lock);
103 
104 	return -1;
105 }
106 
107 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
108 {
109 	spin_lock(&tiqn->tiqn_state_lock);
110 	tiqn->tiqn_access_count--;
111 	spin_unlock(&tiqn->tiqn_state_lock);
112 }
113 
114 /*
115  * Note that IQN formatting is expected to be done in userspace, and
116  * no explict IQN format checks are done here.
117  */
118 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
119 {
120 	struct iscsi_tiqn *tiqn = NULL;
121 	int ret;
122 
123 	if (strlen(buf) >= ISCSI_IQN_LEN) {
124 		pr_err("Target IQN exceeds %d bytes\n",
125 				ISCSI_IQN_LEN);
126 		return ERR_PTR(-EINVAL);
127 	}
128 
129 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
130 	if (!tiqn) {
131 		pr_err("Unable to allocate struct iscsi_tiqn\n");
132 		return ERR_PTR(-ENOMEM);
133 	}
134 
135 	sprintf(tiqn->tiqn, "%s", buf);
136 	INIT_LIST_HEAD(&tiqn->tiqn_list);
137 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
138 	spin_lock_init(&tiqn->tiqn_state_lock);
139 	spin_lock_init(&tiqn->tiqn_tpg_lock);
140 	spin_lock_init(&tiqn->sess_err_stats.lock);
141 	spin_lock_init(&tiqn->login_stats.lock);
142 	spin_lock_init(&tiqn->logout_stats.lock);
143 
144 	if (!idr_pre_get(&tiqn_idr, GFP_KERNEL)) {
145 		pr_err("idr_pre_get() for tiqn_idr failed\n");
146 		kfree(tiqn);
147 		return ERR_PTR(-ENOMEM);
148 	}
149 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
150 
151 	spin_lock(&tiqn_lock);
152 	ret = idr_get_new(&tiqn_idr, NULL, &tiqn->tiqn_index);
153 	if (ret < 0) {
154 		pr_err("idr_get_new() failed for tiqn->tiqn_index\n");
155 		spin_unlock(&tiqn_lock);
156 		kfree(tiqn);
157 		return ERR_PTR(ret);
158 	}
159 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
160 	spin_unlock(&tiqn_lock);
161 
162 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
163 
164 	return tiqn;
165 
166 }
167 
168 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
169 {
170 	/*
171 	 * Wait for accesses to said struct iscsi_tiqn to end.
172 	 */
173 	spin_lock(&tiqn->tiqn_state_lock);
174 	while (tiqn->tiqn_access_count != 0) {
175 		spin_unlock(&tiqn->tiqn_state_lock);
176 		msleep(10);
177 		spin_lock(&tiqn->tiqn_state_lock);
178 	}
179 	spin_unlock(&tiqn->tiqn_state_lock);
180 }
181 
182 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
183 {
184 	/*
185 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
186 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
187 	 * attempts to access this struct iscsi_tiqn will fail from both transport
188 	 * fabric and control code paths.
189 	 */
190 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
191 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
192 		return;
193 	}
194 
195 	iscsit_wait_for_tiqn(tiqn);
196 
197 	spin_lock(&tiqn_lock);
198 	list_del(&tiqn->tiqn_list);
199 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
200 	spin_unlock(&tiqn_lock);
201 
202 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
203 			tiqn->tiqn);
204 	kfree(tiqn);
205 }
206 
207 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
208 {
209 	int ret;
210 	/*
211 	 * Determine if the network portal is accepting storage traffic.
212 	 */
213 	spin_lock_bh(&np->np_thread_lock);
214 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
215 		spin_unlock_bh(&np->np_thread_lock);
216 		return -1;
217 	}
218 	if (np->np_login_tpg) {
219 		pr_err("np->np_login_tpg() is not NULL!\n");
220 		spin_unlock_bh(&np->np_thread_lock);
221 		return -1;
222 	}
223 	spin_unlock_bh(&np->np_thread_lock);
224 	/*
225 	 * Determine if the portal group is accepting storage traffic.
226 	 */
227 	spin_lock_bh(&tpg->tpg_state_lock);
228 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
229 		spin_unlock_bh(&tpg->tpg_state_lock);
230 		return -1;
231 	}
232 	spin_unlock_bh(&tpg->tpg_state_lock);
233 
234 	/*
235 	 * Here we serialize access across the TIQN+TPG Tuple.
236 	 */
237 	ret = mutex_lock_interruptible(&tpg->np_login_lock);
238 	if ((ret != 0) || signal_pending(current))
239 		return -1;
240 
241 	spin_lock_bh(&np->np_thread_lock);
242 	np->np_login_tpg = tpg;
243 	spin_unlock_bh(&np->np_thread_lock);
244 
245 	return 0;
246 }
247 
248 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
249 {
250 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
251 
252 	spin_lock_bh(&np->np_thread_lock);
253 	np->np_login_tpg = NULL;
254 	spin_unlock_bh(&np->np_thread_lock);
255 
256 	mutex_unlock(&tpg->np_login_lock);
257 
258 	if (tiqn)
259 		iscsit_put_tiqn_for_login(tiqn);
260 
261 	return 0;
262 }
263 
264 static struct iscsi_np *iscsit_get_np(
265 	struct __kernel_sockaddr_storage *sockaddr,
266 	int network_transport)
267 {
268 	struct sockaddr_in *sock_in, *sock_in_e;
269 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
270 	struct iscsi_np *np;
271 	int ip_match = 0;
272 	u16 port;
273 
274 	spin_lock_bh(&np_lock);
275 	list_for_each_entry(np, &g_np_list, np_list) {
276 		spin_lock(&np->np_thread_lock);
277 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
278 			spin_unlock(&np->np_thread_lock);
279 			continue;
280 		}
281 
282 		if (sockaddr->ss_family == AF_INET6) {
283 			sock_in6 = (struct sockaddr_in6 *)sockaddr;
284 			sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
285 
286 			if (!memcmp(&sock_in6->sin6_addr.in6_u,
287 				    &sock_in6_e->sin6_addr.in6_u,
288 				    sizeof(struct in6_addr)))
289 				ip_match = 1;
290 
291 			port = ntohs(sock_in6->sin6_port);
292 		} else {
293 			sock_in = (struct sockaddr_in *)sockaddr;
294 			sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
295 
296 			if (sock_in->sin_addr.s_addr ==
297 			    sock_in_e->sin_addr.s_addr)
298 				ip_match = 1;
299 
300 			port = ntohs(sock_in->sin_port);
301 		}
302 
303 		if ((ip_match == 1) && (np->np_port == port) &&
304 		    (np->np_network_transport == network_transport)) {
305 			/*
306 			 * Increment the np_exports reference count now to
307 			 * prevent iscsit_del_np() below from being called
308 			 * while iscsi_tpg_add_network_portal() is called.
309 			 */
310 			np->np_exports++;
311 			spin_unlock(&np->np_thread_lock);
312 			spin_unlock_bh(&np_lock);
313 			return np;
314 		}
315 		spin_unlock(&np->np_thread_lock);
316 	}
317 	spin_unlock_bh(&np_lock);
318 
319 	return NULL;
320 }
321 
322 struct iscsi_np *iscsit_add_np(
323 	struct __kernel_sockaddr_storage *sockaddr,
324 	char *ip_str,
325 	int network_transport)
326 {
327 	struct sockaddr_in *sock_in;
328 	struct sockaddr_in6 *sock_in6;
329 	struct iscsi_np *np;
330 	int ret;
331 	/*
332 	 * Locate the existing struct iscsi_np if already active..
333 	 */
334 	np = iscsit_get_np(sockaddr, network_transport);
335 	if (np)
336 		return np;
337 
338 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
339 	if (!np) {
340 		pr_err("Unable to allocate memory for struct iscsi_np\n");
341 		return ERR_PTR(-ENOMEM);
342 	}
343 
344 	np->np_flags |= NPF_IP_NETWORK;
345 	if (sockaddr->ss_family == AF_INET6) {
346 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
347 		snprintf(np->np_ip, IPV6_ADDRESS_SPACE, "%s", ip_str);
348 		np->np_port = ntohs(sock_in6->sin6_port);
349 	} else {
350 		sock_in = (struct sockaddr_in *)sockaddr;
351 		sprintf(np->np_ip, "%s", ip_str);
352 		np->np_port = ntohs(sock_in->sin_port);
353 	}
354 
355 	np->np_network_transport = network_transport;
356 	spin_lock_init(&np->np_thread_lock);
357 	init_completion(&np->np_restart_comp);
358 	INIT_LIST_HEAD(&np->np_list);
359 
360 	ret = iscsi_target_setup_login_socket(np, sockaddr);
361 	if (ret != 0) {
362 		kfree(np);
363 		return ERR_PTR(ret);
364 	}
365 
366 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
367 	if (IS_ERR(np->np_thread)) {
368 		pr_err("Unable to create kthread: iscsi_np\n");
369 		ret = PTR_ERR(np->np_thread);
370 		kfree(np);
371 		return ERR_PTR(ret);
372 	}
373 	/*
374 	 * Increment the np_exports reference count now to prevent
375 	 * iscsit_del_np() below from being run while a new call to
376 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
377 	 * active.  We don't need to hold np->np_thread_lock at this
378 	 * point because iscsi_np has not been added to g_np_list yet.
379 	 */
380 	np->np_exports = 1;
381 
382 	spin_lock_bh(&np_lock);
383 	list_add_tail(&np->np_list, &g_np_list);
384 	spin_unlock_bh(&np_lock);
385 
386 	pr_debug("CORE[0] - Added Network Portal: %s:%hu on %s\n",
387 		np->np_ip, np->np_port, (np->np_network_transport == ISCSI_TCP) ?
388 		"TCP" : "SCTP");
389 
390 	return np;
391 }
392 
393 int iscsit_reset_np_thread(
394 	struct iscsi_np *np,
395 	struct iscsi_tpg_np *tpg_np,
396 	struct iscsi_portal_group *tpg)
397 {
398 	spin_lock_bh(&np->np_thread_lock);
399 	if (tpg && tpg_np) {
400 		/*
401 		 * The reset operation need only be performed when the
402 		 * passed struct iscsi_portal_group has a login in progress
403 		 * to one of the network portals.
404 		 */
405 		if (tpg_np->tpg_np->np_login_tpg != tpg) {
406 			spin_unlock_bh(&np->np_thread_lock);
407 			return 0;
408 		}
409 	}
410 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
411 		spin_unlock_bh(&np->np_thread_lock);
412 		return 0;
413 	}
414 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
415 
416 	if (np->np_thread) {
417 		spin_unlock_bh(&np->np_thread_lock);
418 		send_sig(SIGINT, np->np_thread, 1);
419 		wait_for_completion(&np->np_restart_comp);
420 		spin_lock_bh(&np->np_thread_lock);
421 	}
422 	spin_unlock_bh(&np->np_thread_lock);
423 
424 	return 0;
425 }
426 
427 int iscsit_del_np_comm(struct iscsi_np *np)
428 {
429 	if (!np->np_socket)
430 		return 0;
431 
432 	/*
433 	 * Some network transports allocate their own struct sock->file,
434 	 * see  if we need to free any additional allocated resources.
435 	 */
436 	if (np->np_flags & NPF_SCTP_STRUCT_FILE) {
437 		kfree(np->np_socket->file);
438 		np->np_socket->file = NULL;
439 	}
440 
441 	sock_release(np->np_socket);
442 	return 0;
443 }
444 
445 int iscsit_del_np(struct iscsi_np *np)
446 {
447 	spin_lock_bh(&np->np_thread_lock);
448 	np->np_exports--;
449 	if (np->np_exports) {
450 		spin_unlock_bh(&np->np_thread_lock);
451 		return 0;
452 	}
453 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
454 	spin_unlock_bh(&np->np_thread_lock);
455 
456 	if (np->np_thread) {
457 		/*
458 		 * We need to send the signal to wakeup Linux/Net
459 		 * which may be sleeping in sock_accept()..
460 		 */
461 		send_sig(SIGINT, np->np_thread, 1);
462 		kthread_stop(np->np_thread);
463 	}
464 	iscsit_del_np_comm(np);
465 
466 	spin_lock_bh(&np_lock);
467 	list_del(&np->np_list);
468 	spin_unlock_bh(&np_lock);
469 
470 	pr_debug("CORE[0] - Removed Network Portal: %s:%hu on %s\n",
471 		np->np_ip, np->np_port, (np->np_network_transport == ISCSI_TCP) ?
472 		"TCP" : "SCTP");
473 
474 	kfree(np);
475 	return 0;
476 }
477 
478 static int __init iscsi_target_init_module(void)
479 {
480 	int ret = 0;
481 
482 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
483 
484 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
485 	if (!iscsit_global) {
486 		pr_err("Unable to allocate memory for iscsit_global\n");
487 		return -1;
488 	}
489 	mutex_init(&auth_id_lock);
490 	spin_lock_init(&sess_idr_lock);
491 	idr_init(&tiqn_idr);
492 	idr_init(&sess_idr);
493 
494 	ret = iscsi_target_register_configfs();
495 	if (ret < 0)
496 		goto out;
497 
498 	ret = iscsi_thread_set_init();
499 	if (ret < 0)
500 		goto configfs_out;
501 
502 	if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
503 			TARGET_THREAD_SET_COUNT) {
504 		pr_err("iscsi_allocate_thread_sets() returned"
505 			" unexpected value!\n");
506 		goto ts_out1;
507 	}
508 
509 	lio_cmd_cache = kmem_cache_create("lio_cmd_cache",
510 			sizeof(struct iscsi_cmd), __alignof__(struct iscsi_cmd),
511 			0, NULL);
512 	if (!lio_cmd_cache) {
513 		pr_err("Unable to kmem_cache_create() for"
514 				" lio_cmd_cache\n");
515 		goto ts_out2;
516 	}
517 
518 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
519 			sizeof(struct iscsi_queue_req),
520 			__alignof__(struct iscsi_queue_req), 0, NULL);
521 	if (!lio_qr_cache) {
522 		pr_err("nable to kmem_cache_create() for"
523 				" lio_qr_cache\n");
524 		goto cmd_out;
525 	}
526 
527 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
528 			sizeof(struct iscsi_datain_req),
529 			__alignof__(struct iscsi_datain_req), 0, NULL);
530 	if (!lio_dr_cache) {
531 		pr_err("Unable to kmem_cache_create() for"
532 				" lio_dr_cache\n");
533 		goto qr_out;
534 	}
535 
536 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
537 			sizeof(struct iscsi_ooo_cmdsn),
538 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
539 	if (!lio_ooo_cache) {
540 		pr_err("Unable to kmem_cache_create() for"
541 				" lio_ooo_cache\n");
542 		goto dr_out;
543 	}
544 
545 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
546 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
547 			0, NULL);
548 	if (!lio_r2t_cache) {
549 		pr_err("Unable to kmem_cache_create() for"
550 				" lio_r2t_cache\n");
551 		goto ooo_out;
552 	}
553 
554 	if (iscsit_load_discovery_tpg() < 0)
555 		goto r2t_out;
556 
557 	return ret;
558 r2t_out:
559 	kmem_cache_destroy(lio_r2t_cache);
560 ooo_out:
561 	kmem_cache_destroy(lio_ooo_cache);
562 dr_out:
563 	kmem_cache_destroy(lio_dr_cache);
564 qr_out:
565 	kmem_cache_destroy(lio_qr_cache);
566 cmd_out:
567 	kmem_cache_destroy(lio_cmd_cache);
568 ts_out2:
569 	iscsi_deallocate_thread_sets();
570 ts_out1:
571 	iscsi_thread_set_free();
572 configfs_out:
573 	iscsi_target_deregister_configfs();
574 out:
575 	kfree(iscsit_global);
576 	return -ENOMEM;
577 }
578 
579 static void __exit iscsi_target_cleanup_module(void)
580 {
581 	iscsi_deallocate_thread_sets();
582 	iscsi_thread_set_free();
583 	iscsit_release_discovery_tpg();
584 	kmem_cache_destroy(lio_cmd_cache);
585 	kmem_cache_destroy(lio_qr_cache);
586 	kmem_cache_destroy(lio_dr_cache);
587 	kmem_cache_destroy(lio_ooo_cache);
588 	kmem_cache_destroy(lio_r2t_cache);
589 
590 	iscsi_target_deregister_configfs();
591 
592 	kfree(iscsit_global);
593 }
594 
595 int iscsit_add_reject(
596 	u8 reason,
597 	int fail_conn,
598 	unsigned char *buf,
599 	struct iscsi_conn *conn)
600 {
601 	struct iscsi_cmd *cmd;
602 	struct iscsi_reject *hdr;
603 	int ret;
604 
605 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
606 	if (!cmd)
607 		return -1;
608 
609 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
610 	if (fail_conn)
611 		cmd->cmd_flags |= ICF_REJECT_FAIL_CONN;
612 
613 	hdr	= (struct iscsi_reject *) cmd->pdu;
614 	hdr->reason = reason;
615 
616 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
617 	if (!cmd->buf_ptr) {
618 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
619 		iscsit_release_cmd(cmd);
620 		return -1;
621 	}
622 
623 	spin_lock_bh(&conn->cmd_lock);
624 	list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
625 	spin_unlock_bh(&conn->cmd_lock);
626 
627 	cmd->i_state = ISTATE_SEND_REJECT;
628 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
629 
630 	ret = wait_for_completion_interruptible(&cmd->reject_comp);
631 	if (ret != 0)
632 		return -1;
633 
634 	return (!fail_conn) ? 0 : -1;
635 }
636 
637 int iscsit_add_reject_from_cmd(
638 	u8 reason,
639 	int fail_conn,
640 	int add_to_conn,
641 	unsigned char *buf,
642 	struct iscsi_cmd *cmd)
643 {
644 	struct iscsi_conn *conn;
645 	struct iscsi_reject *hdr;
646 	int ret;
647 
648 	if (!cmd->conn) {
649 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
650 				cmd->init_task_tag);
651 		return -1;
652 	}
653 	conn = cmd->conn;
654 
655 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
656 	if (fail_conn)
657 		cmd->cmd_flags |= ICF_REJECT_FAIL_CONN;
658 
659 	hdr	= (struct iscsi_reject *) cmd->pdu;
660 	hdr->reason = reason;
661 
662 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
663 	if (!cmd->buf_ptr) {
664 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
665 		iscsit_release_cmd(cmd);
666 		return -1;
667 	}
668 
669 	if (add_to_conn) {
670 		spin_lock_bh(&conn->cmd_lock);
671 		list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
672 		spin_unlock_bh(&conn->cmd_lock);
673 	}
674 
675 	cmd->i_state = ISTATE_SEND_REJECT;
676 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
677 
678 	ret = wait_for_completion_interruptible(&cmd->reject_comp);
679 	if (ret != 0)
680 		return -1;
681 
682 	return (!fail_conn) ? 0 : -1;
683 }
684 
685 /*
686  * Map some portion of the allocated scatterlist to an iovec, suitable for
687  * kernel sockets to copy data in/out. This handles both pages and slab-allocated
688  * buffers, since we have been tricky and mapped t_mem_sg to the buffer in
689  * either case (see iscsit_alloc_buffs)
690  */
691 static int iscsit_map_iovec(
692 	struct iscsi_cmd *cmd,
693 	struct kvec *iov,
694 	u32 data_offset,
695 	u32 data_length)
696 {
697 	u32 i = 0;
698 	struct scatterlist *sg;
699 	unsigned int page_off;
700 
701 	/*
702 	 * We have a private mapping of the allocated pages in t_mem_sg.
703 	 * At this point, we also know each contains a page.
704 	 */
705 	sg = &cmd->t_mem_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_list) {
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 = (cmd->se_cmd.t_data_nents == 0) ? 1 :
764 				cmd->se_cmd.t_data_nents;
765 
766 	iov_count += ISCSI_IOV_DATA_BUFFER;
767 
768 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
769 	if (!cmd->iov_data) {
770 		pr_err("Unable to allocate cmd->iov_data\n");
771 		return -ENOMEM;
772 	}
773 
774 	cmd->orig_iov_data_count = iov_count;
775 	return 0;
776 }
777 
778 static int iscsit_alloc_buffs(struct iscsi_cmd *cmd)
779 {
780 	struct scatterlist *sgl;
781 	u32 length = cmd->se_cmd.data_length;
782 	int nents = DIV_ROUND_UP(length, PAGE_SIZE);
783 	int i = 0, ret;
784 	/*
785 	 * If no SCSI payload is present, allocate the default iovecs used for
786 	 * iSCSI PDU Header
787 	 */
788 	if (!length)
789 		return iscsit_allocate_iovecs(cmd);
790 
791 	sgl = kzalloc(sizeof(*sgl) * nents, GFP_KERNEL);
792 	if (!sgl)
793 		return -ENOMEM;
794 
795 	sg_init_table(sgl, nents);
796 
797 	while (length) {
798 		int buf_size = min_t(int, length, PAGE_SIZE);
799 		struct page *page;
800 
801 		page = alloc_page(GFP_KERNEL | __GFP_ZERO);
802 		if (!page)
803 			goto page_alloc_failed;
804 
805 		sg_set_page(&sgl[i], page, buf_size, 0);
806 
807 		length -= buf_size;
808 		i++;
809 	}
810 
811 	cmd->t_mem_sg = sgl;
812 	cmd->t_mem_sg_nents = nents;
813 
814 	/* BIDI ops not supported */
815 
816 	/* Tell the core about our preallocated memory */
817 	transport_generic_map_mem_to_cmd(&cmd->se_cmd, sgl, nents, NULL, 0);
818 	/*
819 	 * Allocate iovecs for SCSI payload after transport_generic_map_mem_to_cmd
820 	 * so that cmd->se_cmd.t_tasks_se_num has been set.
821 	 */
822         ret = iscsit_allocate_iovecs(cmd);
823         if (ret < 0)
824 		goto page_alloc_failed;
825 
826 	return 0;
827 
828 page_alloc_failed:
829 	while (i >= 0) {
830 		__free_page(sg_page(&sgl[i]));
831 		i--;
832 	}
833 	kfree(cmd->t_mem_sg);
834 	cmd->t_mem_sg = NULL;
835 	return -ENOMEM;
836 }
837 
838 static int iscsit_handle_scsi_cmd(
839 	struct iscsi_conn *conn,
840 	unsigned char *buf)
841 {
842 	int	data_direction, cmdsn_ret = 0, immed_ret, ret, transport_ret;
843 	int	dump_immediate_data = 0, send_check_condition = 0, payload_length;
844 	struct iscsi_cmd	*cmd = NULL;
845 	struct iscsi_scsi_req *hdr;
846 
847 	spin_lock_bh(&conn->sess->session_stats_lock);
848 	conn->sess->cmd_pdus++;
849 	if (conn->sess->se_sess->se_node_acl) {
850 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
851 		conn->sess->se_sess->se_node_acl->num_cmds++;
852 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
853 	}
854 	spin_unlock_bh(&conn->sess->session_stats_lock);
855 
856 	hdr			= (struct iscsi_scsi_req *) buf;
857 	payload_length		= ntoh24(hdr->dlength);
858 	hdr->itt		= be32_to_cpu(hdr->itt);
859 	hdr->data_length	= be32_to_cpu(hdr->data_length);
860 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
861 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
862 
863 	/* FIXME; Add checks for AdditionalHeaderSegment */
864 
865 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
866 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
867 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
868 				" not set. Bad iSCSI Initiator.\n");
869 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
870 				buf, conn);
871 	}
872 
873 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
874 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
875 		/*
876 		 * Vmware ESX v3.0 uses a modified Cisco Initiator (v3.4.2)
877 		 * that adds support for RESERVE/RELEASE.  There is a bug
878 		 * add with this new functionality that sets R/W bits when
879 		 * neither CDB carries any READ or WRITE datapayloads.
880 		 */
881 		if ((hdr->cdb[0] == 0x16) || (hdr->cdb[0] == 0x17)) {
882 			hdr->flags &= ~ISCSI_FLAG_CMD_READ;
883 			hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
884 			goto done;
885 		}
886 
887 		pr_err("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
888 			" set when Expected Data Transfer Length is 0 for"
889 			" CDB: 0x%02x. Bad iSCSI Initiator.\n", hdr->cdb[0]);
890 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
891 				buf, conn);
892 	}
893 done:
894 
895 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
896 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
897 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
898 			" MUST be set if Expected Data Transfer Length is not 0."
899 			" Bad iSCSI Initiator\n");
900 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
901 				buf, conn);
902 	}
903 
904 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
905 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
906 		pr_err("Bidirectional operations not supported!\n");
907 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
908 				buf, conn);
909 	}
910 
911 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
912 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
913 				" Scsi Command PDU.\n");
914 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
915 				buf, conn);
916 	}
917 
918 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
919 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
920 			" protocol error.\n", payload_length);
921 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
922 				buf, conn);
923 	}
924 
925 	if ((hdr->data_length == payload_length) &&
926 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
927 		pr_err("Expected Data Transfer Length and Length of"
928 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
929 			" bit is not set protocol error\n");
930 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
931 				buf, conn);
932 	}
933 
934 	if (payload_length > hdr->data_length) {
935 		pr_err("DataSegmentLength: %u is greater than"
936 			" EDTL: %u, protocol error.\n", payload_length,
937 				hdr->data_length);
938 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
939 				buf, conn);
940 	}
941 
942 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
943 		pr_err("DataSegmentLength: %u is greater than"
944 			" MaxRecvDataSegmentLength: %u, protocol error.\n",
945 			payload_length, conn->conn_ops->MaxRecvDataSegmentLength);
946 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
947 				buf, conn);
948 	}
949 
950 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
951 		pr_err("DataSegmentLength: %u is greater than"
952 			" FirstBurstLength: %u, protocol error.\n",
953 			payload_length, conn->sess->sess_ops->FirstBurstLength);
954 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_INVALID, 1,
955 					buf, conn);
956 	}
957 
958 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
959 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
960 			  DMA_NONE;
961 
962 	cmd = iscsit_allocate_se_cmd(conn, hdr->data_length, data_direction,
963 				(hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK));
964 	if (!cmd)
965 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES, 1,
966 					buf, conn);
967 
968 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
969 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
970 		hdr->cmdsn, hdr->data_length, payload_length, conn->cid);
971 
972 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
973 	cmd->i_state		= ISTATE_NEW_CMD;
974 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
975 	cmd->immediate_data	= (payload_length) ? 1 : 0;
976 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
977 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
978 	if (cmd->unsolicited_data)
979 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
980 
981 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
982 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
983 		spin_lock_bh(&conn->sess->ttt_lock);
984 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
985 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
986 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
987 		spin_unlock_bh(&conn->sess->ttt_lock);
988 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
989 		cmd->targ_xfer_tag = 0xFFFFFFFF;
990 	cmd->cmd_sn		= hdr->cmdsn;
991 	cmd->exp_stat_sn	= hdr->exp_statsn;
992 	cmd->first_burst_len	= payload_length;
993 
994 	if (cmd->data_direction == DMA_FROM_DEVICE) {
995 		struct iscsi_datain_req *dr;
996 
997 		dr = iscsit_allocate_datain_req();
998 		if (!dr)
999 			return iscsit_add_reject_from_cmd(
1000 					ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1001 					1, 1, buf, cmd);
1002 
1003 		iscsit_attach_datain_req(cmd, dr);
1004 	}
1005 
1006 	/*
1007 	 * The CDB is going to an se_device_t.
1008 	 */
1009 	ret = iscsit_get_lun_for_cmd(cmd, hdr->cdb,
1010 				get_unaligned_le64(&hdr->lun));
1011 	if (ret < 0) {
1012 		if (cmd->se_cmd.scsi_sense_reason == TCM_NON_EXISTENT_LUN) {
1013 			pr_debug("Responding to non-acl'ed,"
1014 				" non-existent or non-exported iSCSI LUN:"
1015 				" 0x%016Lx\n", get_unaligned_le64(&hdr->lun));
1016 		}
1017 		send_check_condition = 1;
1018 		goto attach_cmd;
1019 	}
1020 	/*
1021 	 * The Initiator Node has access to the LUN (the addressing method
1022 	 * is handled inside of iscsit_get_lun_for_cmd()).  Now it's time to
1023 	 * allocate 1->N transport tasks (depending on sector count and
1024 	 * maximum request size the physical HBA(s) can handle.
1025 	 */
1026 	transport_ret = transport_generic_allocate_tasks(&cmd->se_cmd, hdr->cdb);
1027 	if (transport_ret == -ENOMEM) {
1028 		return iscsit_add_reject_from_cmd(
1029 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1030 				1, 1, buf, cmd);
1031 	} else if (transport_ret == -EINVAL) {
1032 		/*
1033 		 * Unsupported SAM Opcode.  CHECK_CONDITION will be sent
1034 		 * in iscsit_execute_cmd() during the CmdSN OOO Execution
1035 		 * Mechinism.
1036 		 */
1037 		send_check_condition = 1;
1038 	} else {
1039 		cmd->data_length = cmd->se_cmd.data_length;
1040 
1041 		if (iscsit_decide_list_to_build(cmd, payload_length) < 0)
1042 			return iscsit_add_reject_from_cmd(
1043 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1044 				1, 1, buf, cmd);
1045 	}
1046 
1047 attach_cmd:
1048 	spin_lock_bh(&conn->cmd_lock);
1049 	list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
1050 	spin_unlock_bh(&conn->cmd_lock);
1051 	/*
1052 	 * Check if we need to delay processing because of ALUA
1053 	 * Active/NonOptimized primary access state..
1054 	 */
1055 	core_alua_check_nonop_delay(&cmd->se_cmd);
1056 	/*
1057 	 * Allocate and setup SGL used with transport_generic_map_mem_to_cmd().
1058 	 * also call iscsit_allocate_iovecs()
1059 	 */
1060 	ret = iscsit_alloc_buffs(cmd);
1061 	if (ret < 0)
1062 		return iscsit_add_reject_from_cmd(
1063 				ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1064 				1, 1, buf, cmd);
1065 	/*
1066 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1067 	 * the Immediate Bit is not set, and no Immediate
1068 	 * Data is attached.
1069 	 *
1070 	 * A PDU/CmdSN carrying Immediate Data can only
1071 	 * be processed after the DataCRC has passed.
1072 	 * If the DataCRC fails, the CmdSN MUST NOT
1073 	 * be acknowledged. (See below)
1074 	 */
1075 	if (!cmd->immediate_data) {
1076 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1077 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1078 			return 0;
1079 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1080 			return iscsit_add_reject_from_cmd(
1081 				ISCSI_REASON_PROTOCOL_ERROR,
1082 				1, 0, buf, cmd);
1083 	}
1084 
1085 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1086 
1087 	/*
1088 	 * If no Immediate Data is attached, it's OK to return now.
1089 	 */
1090 	if (!cmd->immediate_data) {
1091 		if (send_check_condition)
1092 			return 0;
1093 
1094 		if (cmd->unsolicited_data) {
1095 			iscsit_set_dataout_sequence_values(cmd);
1096 
1097 			spin_lock_bh(&cmd->dataout_timeout_lock);
1098 			iscsit_start_dataout_timer(cmd, cmd->conn);
1099 			spin_unlock_bh(&cmd->dataout_timeout_lock);
1100 		}
1101 
1102 		return 0;
1103 	}
1104 
1105 	/*
1106 	 * Early CHECK_CONDITIONs never make it to the transport processing
1107 	 * thread.  They are processed in CmdSN order by
1108 	 * iscsit_check_received_cmdsn() below.
1109 	 */
1110 	if (send_check_condition) {
1111 		immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1112 		dump_immediate_data = 1;
1113 		goto after_immediate_data;
1114 	}
1115 	/*
1116 	 * Call directly into transport_generic_new_cmd() to perform
1117 	 * the backend memory allocation.
1118 	 */
1119 	ret = transport_generic_new_cmd(&cmd->se_cmd);
1120 	if (ret < 0) {
1121 		immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1122 		dump_immediate_data = 1;
1123 		goto after_immediate_data;
1124 	}
1125 
1126 	immed_ret = iscsit_handle_immediate_data(cmd, buf, payload_length);
1127 after_immediate_data:
1128 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1129 		/*
1130 		 * A PDU/CmdSN carrying Immediate Data passed
1131 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1132 		 * Immediate Bit is not set.
1133 		 */
1134 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1135 		/*
1136 		 * Special case for Unsupported SAM WRITE Opcodes
1137 		 * and ImmediateData=Yes.
1138 		 */
1139 		if (dump_immediate_data) {
1140 			if (iscsit_dump_data_payload(conn, payload_length, 1) < 0)
1141 				return -1;
1142 		} else if (cmd->unsolicited_data) {
1143 			iscsit_set_dataout_sequence_values(cmd);
1144 
1145 			spin_lock_bh(&cmd->dataout_timeout_lock);
1146 			iscsit_start_dataout_timer(cmd, cmd->conn);
1147 			spin_unlock_bh(&cmd->dataout_timeout_lock);
1148 		}
1149 
1150 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1151 			return iscsit_add_reject_from_cmd(
1152 				ISCSI_REASON_PROTOCOL_ERROR,
1153 				1, 0, buf, cmd);
1154 
1155 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1156 		/*
1157 		 * Immediate Data failed DataCRC and ERL>=1,
1158 		 * silently drop this PDU and let the initiator
1159 		 * plug the CmdSN gap.
1160 		 *
1161 		 * FIXME: Send Unsolicited NOPIN with reserved
1162 		 * TTT here to help the initiator figure out
1163 		 * the missing CmdSN, although they should be
1164 		 * intelligent enough to determine the missing
1165 		 * CmdSN and issue a retry to plug the sequence.
1166 		 */
1167 		cmd->i_state = ISTATE_REMOVE;
1168 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
1169 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1170 		return -1;
1171 
1172 	return 0;
1173 }
1174 
1175 static u32 iscsit_do_crypto_hash_sg(
1176 	struct hash_desc *hash,
1177 	struct iscsi_cmd *cmd,
1178 	u32 data_offset,
1179 	u32 data_length,
1180 	u32 padding,
1181 	u8 *pad_bytes)
1182 {
1183 	u32 data_crc;
1184 	u32 i;
1185 	struct scatterlist *sg;
1186 	unsigned int page_off;
1187 
1188 	crypto_hash_init(hash);
1189 
1190 	sg = cmd->first_data_sg;
1191 	page_off = cmd->first_data_sg_off;
1192 
1193 	i = 0;
1194 	while (data_length) {
1195 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1196 
1197 		crypto_hash_update(hash, &sg[i], cur_len);
1198 
1199 		data_length -= cur_len;
1200 		page_off = 0;
1201 		i++;
1202 	}
1203 
1204 	if (padding) {
1205 		struct scatterlist pad_sg;
1206 
1207 		sg_init_one(&pad_sg, pad_bytes, padding);
1208 		crypto_hash_update(hash, &pad_sg, padding);
1209 	}
1210 	crypto_hash_final(hash, (u8 *) &data_crc);
1211 
1212 	return data_crc;
1213 }
1214 
1215 static void iscsit_do_crypto_hash_buf(
1216 	struct hash_desc *hash,
1217 	unsigned char *buf,
1218 	u32 payload_length,
1219 	u32 padding,
1220 	u8 *pad_bytes,
1221 	u8 *data_crc)
1222 {
1223 	struct scatterlist sg;
1224 
1225 	crypto_hash_init(hash);
1226 
1227 	sg_init_one(&sg, buf, payload_length);
1228 	crypto_hash_update(hash, &sg, payload_length);
1229 
1230 	if (padding) {
1231 		sg_init_one(&sg, pad_bytes, padding);
1232 		crypto_hash_update(hash, &sg, padding);
1233 	}
1234 	crypto_hash_final(hash, data_crc);
1235 }
1236 
1237 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1238 {
1239 	int iov_ret, ooo_cmdsn = 0, ret;
1240 	u8 data_crc_failed = 0;
1241 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0;
1242 	u32 rx_size = 0, payload_length;
1243 	struct iscsi_cmd *cmd = NULL;
1244 	struct se_cmd *se_cmd;
1245 	struct iscsi_data *hdr;
1246 	struct kvec *iov;
1247 	unsigned long flags;
1248 
1249 	hdr			= (struct iscsi_data *) buf;
1250 	payload_length		= ntoh24(hdr->dlength);
1251 	hdr->itt		= be32_to_cpu(hdr->itt);
1252 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1253 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1254 	hdr->datasn		= be32_to_cpu(hdr->datasn);
1255 	hdr->offset		= be32_to_cpu(hdr->offset);
1256 
1257 	if (!payload_length) {
1258 		pr_err("DataOUT payload is ZERO, protocol error.\n");
1259 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1260 					buf, conn);
1261 	}
1262 
1263 	/* iSCSI write */
1264 	spin_lock_bh(&conn->sess->session_stats_lock);
1265 	conn->sess->rx_data_octets += payload_length;
1266 	if (conn->sess->se_sess->se_node_acl) {
1267 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
1268 		conn->sess->se_sess->se_node_acl->write_bytes += payload_length;
1269 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
1270 	}
1271 	spin_unlock_bh(&conn->sess->session_stats_lock);
1272 
1273 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1274 		pr_err("DataSegmentLength: %u is greater than"
1275 			" MaxRecvDataSegmentLength: %u\n", payload_length,
1276 			conn->conn_ops->MaxRecvDataSegmentLength);
1277 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1278 					buf, conn);
1279 	}
1280 
1281 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1282 			payload_length);
1283 	if (!cmd)
1284 		return 0;
1285 
1286 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1287 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1288 		hdr->itt, hdr->ttt, hdr->datasn, hdr->offset,
1289 		payload_length, conn->cid);
1290 
1291 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1292 		pr_err("Command ITT: 0x%08x received DataOUT after"
1293 			" last DataOUT received, dumping payload\n",
1294 			cmd->init_task_tag);
1295 		return iscsit_dump_data_payload(conn, payload_length, 1);
1296 	}
1297 
1298 	if (cmd->data_direction != DMA_TO_DEVICE) {
1299 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1300 			" NON-WRITE command.\n", cmd->init_task_tag);
1301 		return iscsit_add_reject_from_cmd(ISCSI_REASON_PROTOCOL_ERROR,
1302 				1, 0, buf, cmd);
1303 	}
1304 	se_cmd = &cmd->se_cmd;
1305 	iscsit_mod_dataout_timer(cmd);
1306 
1307 	if ((hdr->offset + payload_length) > cmd->data_length) {
1308 		pr_err("DataOut Offset: %u, Length %u greater than"
1309 			" iSCSI Command EDTL %u, protocol error.\n",
1310 			hdr->offset, payload_length, cmd->data_length);
1311 		return iscsit_add_reject_from_cmd(ISCSI_REASON_BOOKMARK_INVALID,
1312 				1, 0, buf, cmd);
1313 	}
1314 
1315 	if (cmd->unsolicited_data) {
1316 		int dump_unsolicited_data = 0;
1317 
1318 		if (conn->sess->sess_ops->InitialR2T) {
1319 			pr_err("Received unexpected unsolicited data"
1320 				" while InitialR2T=Yes, protocol error.\n");
1321 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1322 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1323 			return -1;
1324 		}
1325 		/*
1326 		 * Special case for dealing with Unsolicited DataOUT
1327 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1328 		 * failures;
1329 		 */
1330 
1331 		/* Something's amiss if we're not in WRITE_PENDING state... */
1332 		spin_lock_irqsave(&se_cmd->t_state_lock, flags);
1333 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1334 		spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
1335 
1336 		spin_lock_irqsave(&se_cmd->t_state_lock, flags);
1337 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) ||
1338 		     (se_cmd->se_cmd_flags & SCF_SCSI_CDB_EXCEPTION))
1339 			dump_unsolicited_data = 1;
1340 		spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
1341 
1342 		if (dump_unsolicited_data) {
1343 			/*
1344 			 * Check if a delayed TASK_ABORTED status needs to
1345 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1346 			 * received with the unsolicitied data out.
1347 			 */
1348 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1349 				iscsit_stop_dataout_timer(cmd);
1350 
1351 			transport_check_aborted_status(se_cmd,
1352 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1353 			return iscsit_dump_data_payload(conn, payload_length, 1);
1354 		}
1355 	} else {
1356 		/*
1357 		 * For the normal solicited data path:
1358 		 *
1359 		 * Check for a delayed TASK_ABORTED status and dump any
1360 		 * incoming data out payload if one exists.  Also, when the
1361 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1362 		 * data out sequence, we decrement outstanding_r2ts.  Once
1363 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1364 		 * TASK_ABORTED status.
1365 		 */
1366 		if (atomic_read(&se_cmd->t_transport_aborted) != 0) {
1367 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1368 				if (--cmd->outstanding_r2ts < 1) {
1369 					iscsit_stop_dataout_timer(cmd);
1370 					transport_check_aborted_status(
1371 							se_cmd, 1);
1372 				}
1373 
1374 			return iscsit_dump_data_payload(conn, payload_length, 1);
1375 		}
1376 	}
1377 	/*
1378 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1379 	 * within-command recovery checks before receiving the payload.
1380 	 */
1381 	ret = iscsit_check_pre_dataout(cmd, buf);
1382 	if (ret == DATAOUT_WITHIN_COMMAND_RECOVERY)
1383 		return 0;
1384 	else if (ret == DATAOUT_CANNOT_RECOVER)
1385 		return -1;
1386 
1387 	rx_size += payload_length;
1388 	iov = &cmd->iov_data[0];
1389 
1390 	iov_ret = iscsit_map_iovec(cmd, iov, hdr->offset, payload_length);
1391 	if (iov_ret < 0)
1392 		return -1;
1393 
1394 	iov_count += iov_ret;
1395 
1396 	padding = ((-payload_length) & 3);
1397 	if (padding != 0) {
1398 		iov[iov_count].iov_base	= cmd->pad_bytes;
1399 		iov[iov_count++].iov_len = padding;
1400 		rx_size += padding;
1401 		pr_debug("Receiving %u padding bytes.\n", padding);
1402 	}
1403 
1404 	if (conn->conn_ops->DataDigest) {
1405 		iov[iov_count].iov_base = &checksum;
1406 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1407 		rx_size += ISCSI_CRC_LEN;
1408 	}
1409 
1410 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1411 
1412 	iscsit_unmap_iovec(cmd);
1413 
1414 	if (rx_got != rx_size)
1415 		return -1;
1416 
1417 	if (conn->conn_ops->DataDigest) {
1418 		u32 data_crc;
1419 
1420 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1421 						    hdr->offset, payload_length, padding,
1422 						    cmd->pad_bytes);
1423 
1424 		if (checksum != data_crc) {
1425 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1426 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1427 				" does not match computed 0x%08x\n",
1428 				hdr->itt, hdr->offset, payload_length,
1429 				hdr->datasn, checksum, data_crc);
1430 			data_crc_failed = 1;
1431 		} else {
1432 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1433 				" %u bytes of Data Out\n", checksum,
1434 				payload_length);
1435 		}
1436 	}
1437 	/*
1438 	 * Increment post receive data and CRC values or perform
1439 	 * within-command recovery.
1440 	 */
1441 	ret = iscsit_check_post_dataout(cmd, buf, data_crc_failed);
1442 	if ((ret == DATAOUT_NORMAL) || (ret == DATAOUT_WITHIN_COMMAND_RECOVERY))
1443 		return 0;
1444 	else if (ret == DATAOUT_SEND_R2T) {
1445 		iscsit_set_dataout_sequence_values(cmd);
1446 		iscsit_build_r2ts_for_cmd(cmd, conn, 0);
1447 	} else if (ret == DATAOUT_SEND_TO_TRANSPORT) {
1448 		/*
1449 		 * Handle extra special case for out of order
1450 		 * Unsolicited Data Out.
1451 		 */
1452 		spin_lock_bh(&cmd->istate_lock);
1453 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1454 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1455 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1456 		spin_unlock_bh(&cmd->istate_lock);
1457 
1458 		iscsit_stop_dataout_timer(cmd);
1459 		return (!ooo_cmdsn) ? transport_generic_handle_data(
1460 					&cmd->se_cmd) : 0;
1461 	} else /* DATAOUT_CANNOT_RECOVER */
1462 		return -1;
1463 
1464 	return 0;
1465 }
1466 
1467 static int iscsit_handle_nop_out(
1468 	struct iscsi_conn *conn,
1469 	unsigned char *buf)
1470 {
1471 	unsigned char *ping_data = NULL;
1472 	int cmdsn_ret, niov = 0, ret = 0, rx_got, rx_size;
1473 	u32 checksum, data_crc, padding = 0, payload_length;
1474 	u64 lun;
1475 	struct iscsi_cmd *cmd = NULL;
1476 	struct kvec *iov = NULL;
1477 	struct iscsi_nopout *hdr;
1478 
1479 	hdr			= (struct iscsi_nopout *) buf;
1480 	payload_length		= ntoh24(hdr->dlength);
1481 	lun			= get_unaligned_le64(&hdr->lun);
1482 	hdr->itt		= be32_to_cpu(hdr->itt);
1483 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1484 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1485 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1486 
1487 	if ((hdr->itt == 0xFFFFFFFF) && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1488 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1489 			" not set, protocol error.\n");
1490 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1491 					buf, conn);
1492 	}
1493 
1494 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1495 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1496 			" greater than MaxRecvDataSegmentLength: %u, protocol"
1497 			" error.\n", payload_length,
1498 			conn->conn_ops->MaxRecvDataSegmentLength);
1499 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1500 					buf, conn);
1501 	}
1502 
1503 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%09x,"
1504 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1505 		(hdr->itt == 0xFFFFFFFF) ? "Response" : "Request",
1506 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1507 		payload_length);
1508 	/*
1509 	 * This is not a response to a Unsolicited NopIN, which means
1510 	 * it can either be a NOPOUT ping request (with a valid ITT),
1511 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1512 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1513 	 * can contain ping data.
1514 	 */
1515 	if (hdr->ttt == 0xFFFFFFFF) {
1516 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1517 		if (!cmd)
1518 			return iscsit_add_reject(
1519 					ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1520 					1, buf, conn);
1521 
1522 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1523 		cmd->i_state		= ISTATE_SEND_NOPIN;
1524 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1525 						1 : 0);
1526 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1527 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1528 		cmd->cmd_sn		= hdr->cmdsn;
1529 		cmd->exp_stat_sn	= hdr->exp_statsn;
1530 		cmd->data_direction	= DMA_NONE;
1531 	}
1532 
1533 	if (payload_length && (hdr->ttt == 0xFFFFFFFF)) {
1534 		rx_size = payload_length;
1535 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1536 		if (!ping_data) {
1537 			pr_err("Unable to allocate memory for"
1538 				" NOPOUT ping data.\n");
1539 			ret = -1;
1540 			goto out;
1541 		}
1542 
1543 		iov = &cmd->iov_misc[0];
1544 		iov[niov].iov_base	= ping_data;
1545 		iov[niov++].iov_len	= payload_length;
1546 
1547 		padding = ((-payload_length) & 3);
1548 		if (padding != 0) {
1549 			pr_debug("Receiving %u additional bytes"
1550 				" for padding.\n", padding);
1551 			iov[niov].iov_base	= &cmd->pad_bytes;
1552 			iov[niov++].iov_len	= padding;
1553 			rx_size += padding;
1554 		}
1555 		if (conn->conn_ops->DataDigest) {
1556 			iov[niov].iov_base	= &checksum;
1557 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1558 			rx_size += ISCSI_CRC_LEN;
1559 		}
1560 
1561 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1562 		if (rx_got != rx_size) {
1563 			ret = -1;
1564 			goto out;
1565 		}
1566 
1567 		if (conn->conn_ops->DataDigest) {
1568 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1569 					ping_data, payload_length,
1570 					padding, cmd->pad_bytes,
1571 					(u8 *)&data_crc);
1572 
1573 			if (checksum != data_crc) {
1574 				pr_err("Ping data CRC32C DataDigest"
1575 				" 0x%08x does not match computed 0x%08x\n",
1576 					checksum, data_crc);
1577 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1578 					pr_err("Unable to recover from"
1579 					" NOPOUT Ping DataCRC failure while in"
1580 						" ERL=0.\n");
1581 					ret = -1;
1582 					goto out;
1583 				} else {
1584 					/*
1585 					 * Silently drop this PDU and let the
1586 					 * initiator plug the CmdSN gap.
1587 					 */
1588 					pr_debug("Dropping NOPOUT"
1589 					" Command CmdSN: 0x%08x due to"
1590 					" DataCRC error.\n", hdr->cmdsn);
1591 					ret = 0;
1592 					goto out;
1593 				}
1594 			} else {
1595 				pr_debug("Got CRC32C DataDigest"
1596 				" 0x%08x for %u bytes of ping data.\n",
1597 					checksum, payload_length);
1598 			}
1599 		}
1600 
1601 		ping_data[payload_length] = '\0';
1602 		/*
1603 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1604 		 */
1605 		cmd->buf_ptr = ping_data;
1606 		cmd->buf_ptr_size = payload_length;
1607 
1608 		pr_debug("Got %u bytes of NOPOUT ping"
1609 			" data.\n", payload_length);
1610 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1611 	}
1612 
1613 	if (hdr->itt != 0xFFFFFFFF) {
1614 		if (!cmd) {
1615 			pr_err("Checking CmdSN for NOPOUT,"
1616 				" but cmd is NULL!\n");
1617 			return -1;
1618 		}
1619 		/*
1620 		 * Initiator is expecting a NopIN ping reply,
1621 		 */
1622 		spin_lock_bh(&conn->cmd_lock);
1623 		list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
1624 		spin_unlock_bh(&conn->cmd_lock);
1625 
1626 		iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1627 
1628 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1629 			iscsit_add_cmd_to_response_queue(cmd, conn,
1630 					cmd->i_state);
1631 			return 0;
1632 		}
1633 
1634 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1635 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1636 			ret = 0;
1637 			goto ping_out;
1638 		}
1639 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1640 			return iscsit_add_reject_from_cmd(
1641 					ISCSI_REASON_PROTOCOL_ERROR,
1642 					1, 0, buf, cmd);
1643 
1644 		return 0;
1645 	}
1646 
1647 	if (hdr->ttt != 0xFFFFFFFF) {
1648 		/*
1649 		 * This was a response to a unsolicited NOPIN ping.
1650 		 */
1651 		cmd = iscsit_find_cmd_from_ttt(conn, hdr->ttt);
1652 		if (!cmd)
1653 			return -1;
1654 
1655 		iscsit_stop_nopin_response_timer(conn);
1656 
1657 		cmd->i_state = ISTATE_REMOVE;
1658 		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
1659 		iscsit_start_nopin_timer(conn);
1660 	} else {
1661 		/*
1662 		 * Initiator is not expecting a NOPIN is response.
1663 		 * Just ignore for now.
1664 		 *
1665 		 * iSCSI v19-91 10.18
1666 		 * "A NOP-OUT may also be used to confirm a changed
1667 		 *  ExpStatSN if another PDU will not be available
1668 		 *  for a long time."
1669 		 */
1670 		ret = 0;
1671 		goto out;
1672 	}
1673 
1674 	return 0;
1675 out:
1676 	if (cmd)
1677 		iscsit_release_cmd(cmd);
1678 ping_out:
1679 	kfree(ping_data);
1680 	return ret;
1681 }
1682 
1683 static int iscsit_handle_task_mgt_cmd(
1684 	struct iscsi_conn *conn,
1685 	unsigned char *buf)
1686 {
1687 	struct iscsi_cmd *cmd;
1688 	struct se_tmr_req *se_tmr;
1689 	struct iscsi_tmr_req *tmr_req;
1690 	struct iscsi_tm *hdr;
1691 	u32 payload_length;
1692 	int out_of_order_cmdsn = 0;
1693 	int ret;
1694 	u8 function;
1695 
1696 	hdr			= (struct iscsi_tm *) buf;
1697 	payload_length		= ntoh24(hdr->dlength);
1698 	hdr->itt		= be32_to_cpu(hdr->itt);
1699 	hdr->rtt		= be32_to_cpu(hdr->rtt);
1700 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1701 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1702 	hdr->refcmdsn		= be32_to_cpu(hdr->refcmdsn);
1703 	hdr->exp_datasn		= be32_to_cpu(hdr->exp_datasn);
1704 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1705 	function = hdr->flags;
1706 
1707 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1708 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1709 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1710 		hdr->rtt, hdr->refcmdsn, conn->cid);
1711 
1712 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1713 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1714 	     (hdr->rtt != ISCSI_RESERVED_TAG))) {
1715 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1716 		hdr->rtt = ISCSI_RESERVED_TAG;
1717 	}
1718 
1719 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1720 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1721 		pr_err("Task Management Request TASK_REASSIGN not"
1722 			" issued as immediate command, bad iSCSI Initiator"
1723 				"implementation\n");
1724 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1725 					buf, conn);
1726 	}
1727 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1728 	    (hdr->refcmdsn != ISCSI_RESERVED_TAG))
1729 		hdr->refcmdsn = ISCSI_RESERVED_TAG;
1730 
1731 	cmd = iscsit_allocate_se_cmd_for_tmr(conn, function);
1732 	if (!cmd)
1733 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1734 					1, buf, conn);
1735 
1736 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1737 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1738 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1739 	cmd->init_task_tag	= hdr->itt;
1740 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1741 	cmd->cmd_sn		= hdr->cmdsn;
1742 	cmd->exp_stat_sn	= hdr->exp_statsn;
1743 	se_tmr			= cmd->se_cmd.se_tmr_req;
1744 	tmr_req			= cmd->tmr_req;
1745 	/*
1746 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1747 	 */
1748 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1749 		ret = iscsit_get_lun_for_tmr(cmd,
1750 				get_unaligned_le64(&hdr->lun));
1751 		if (ret < 0) {
1752 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1753 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1754 			goto attach;
1755 		}
1756 	}
1757 
1758 	switch (function) {
1759 	case ISCSI_TM_FUNC_ABORT_TASK:
1760 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1761 		if (se_tmr->response != ISCSI_TMF_RSP_COMPLETE) {
1762 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1763 			goto attach;
1764 		}
1765 		break;
1766 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1767 	case ISCSI_TM_FUNC_CLEAR_ACA:
1768 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1769 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1770 		break;
1771 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1772 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1773 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1774 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1775 			goto attach;
1776 		}
1777 		break;
1778 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1779 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1780 			cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1781 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1782 			goto attach;
1783 		}
1784 		break;
1785 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1786 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1787 		/*
1788 		 * Perform sanity checks on the ExpDataSN only if the
1789 		 * TASK_REASSIGN was successful.
1790 		 */
1791 		if (se_tmr->response != ISCSI_TMF_RSP_COMPLETE)
1792 			break;
1793 
1794 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1795 			return iscsit_add_reject_from_cmd(
1796 					ISCSI_REASON_BOOKMARK_INVALID, 1, 1,
1797 					buf, cmd);
1798 		break;
1799 	default:
1800 		pr_err("Unknown TMR function: 0x%02x, protocol"
1801 			" error.\n", function);
1802 		cmd->se_cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
1803 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1804 		goto attach;
1805 	}
1806 
1807 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1808 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1809 		se_tmr->call_transport = 1;
1810 attach:
1811 	spin_lock_bh(&conn->cmd_lock);
1812 	list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
1813 	spin_unlock_bh(&conn->cmd_lock);
1814 
1815 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1816 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1817 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1818 			out_of_order_cmdsn = 1;
1819 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1820 			return 0;
1821 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1822 			return iscsit_add_reject_from_cmd(
1823 					ISCSI_REASON_PROTOCOL_ERROR,
1824 					1, 0, buf, cmd);
1825 	}
1826 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1827 
1828 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1829 		return 0;
1830 	/*
1831 	 * Found the referenced task, send to transport for processing.
1832 	 */
1833 	if (se_tmr->call_transport)
1834 		return transport_generic_handle_tmr(&cmd->se_cmd);
1835 
1836 	/*
1837 	 * Could not find the referenced LUN, task, or Task Management
1838 	 * command not authorized or supported.  Change state and
1839 	 * let the tx_thread send the response.
1840 	 *
1841 	 * For connection recovery, this is also the default action for
1842 	 * TMR TASK_REASSIGN.
1843 	 */
1844 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1845 	return 0;
1846 }
1847 
1848 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1849 static int iscsit_handle_text_cmd(
1850 	struct iscsi_conn *conn,
1851 	unsigned char *buf)
1852 {
1853 	char *text_ptr, *text_in;
1854 	int cmdsn_ret, niov = 0, rx_got, rx_size;
1855 	u32 checksum = 0, data_crc = 0, payload_length;
1856 	u32 padding = 0, pad_bytes = 0, text_length = 0;
1857 	struct iscsi_cmd *cmd;
1858 	struct kvec iov[3];
1859 	struct iscsi_text *hdr;
1860 
1861 	hdr			= (struct iscsi_text *) buf;
1862 	payload_length		= ntoh24(hdr->dlength);
1863 	hdr->itt		= be32_to_cpu(hdr->itt);
1864 	hdr->ttt		= be32_to_cpu(hdr->ttt);
1865 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
1866 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
1867 
1868 	if (payload_length > conn->conn_ops->MaxRecvDataSegmentLength) {
1869 		pr_err("Unable to accept text parameter length: %u"
1870 			"greater than MaxRecvDataSegmentLength %u.\n",
1871 		       payload_length, conn->conn_ops->MaxRecvDataSegmentLength);
1872 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
1873 					buf, conn);
1874 	}
1875 
1876 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1877 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1878 		hdr->exp_statsn, payload_length);
1879 
1880 	rx_size = text_length = payload_length;
1881 	if (text_length) {
1882 		text_in = kzalloc(text_length, GFP_KERNEL);
1883 		if (!text_in) {
1884 			pr_err("Unable to allocate memory for"
1885 				" incoming text parameters\n");
1886 			return -1;
1887 		}
1888 
1889 		memset(iov, 0, 3 * sizeof(struct kvec));
1890 		iov[niov].iov_base	= text_in;
1891 		iov[niov++].iov_len	= text_length;
1892 
1893 		padding = ((-payload_length) & 3);
1894 		if (padding != 0) {
1895 			iov[niov].iov_base = &pad_bytes;
1896 			iov[niov++].iov_len  = padding;
1897 			rx_size += padding;
1898 			pr_debug("Receiving %u additional bytes"
1899 					" for padding.\n", padding);
1900 		}
1901 		if (conn->conn_ops->DataDigest) {
1902 			iov[niov].iov_base	= &checksum;
1903 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1904 			rx_size += ISCSI_CRC_LEN;
1905 		}
1906 
1907 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
1908 		if (rx_got != rx_size) {
1909 			kfree(text_in);
1910 			return -1;
1911 		}
1912 
1913 		if (conn->conn_ops->DataDigest) {
1914 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1915 					text_in, text_length,
1916 					padding, (u8 *)&pad_bytes,
1917 					(u8 *)&data_crc);
1918 
1919 			if (checksum != data_crc) {
1920 				pr_err("Text data CRC32C DataDigest"
1921 					" 0x%08x does not match computed"
1922 					" 0x%08x\n", checksum, data_crc);
1923 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1924 					pr_err("Unable to recover from"
1925 					" Text Data digest failure while in"
1926 						" ERL=0.\n");
1927 					kfree(text_in);
1928 					return -1;
1929 				} else {
1930 					/*
1931 					 * Silently drop this PDU and let the
1932 					 * initiator plug the CmdSN gap.
1933 					 */
1934 					pr_debug("Dropping Text"
1935 					" Command CmdSN: 0x%08x due to"
1936 					" DataCRC error.\n", hdr->cmdsn);
1937 					kfree(text_in);
1938 					return 0;
1939 				}
1940 			} else {
1941 				pr_debug("Got CRC32C DataDigest"
1942 					" 0x%08x for %u bytes of text data.\n",
1943 						checksum, text_length);
1944 			}
1945 		}
1946 		text_in[text_length - 1] = '\0';
1947 		pr_debug("Successfully read %d bytes of text"
1948 				" data.\n", text_length);
1949 
1950 		if (strncmp("SendTargets", text_in, 11) != 0) {
1951 			pr_err("Received Text Data that is not"
1952 				" SendTargets, cannot continue.\n");
1953 			kfree(text_in);
1954 			return -1;
1955 		}
1956 		text_ptr = strchr(text_in, '=');
1957 		if (!text_ptr) {
1958 			pr_err("No \"=\" separator found in Text Data,"
1959 				"  cannot continue.\n");
1960 			kfree(text_in);
1961 			return -1;
1962 		}
1963 		if (strncmp("=All", text_ptr, 4) != 0) {
1964 			pr_err("Unable to locate All value for"
1965 				" SendTargets key,  cannot continue.\n");
1966 			kfree(text_in);
1967 			return -1;
1968 		}
1969 /*#warning Support SendTargets=(iSCSI Target Name/Nothing) values. */
1970 		kfree(text_in);
1971 	}
1972 
1973 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
1974 	if (!cmd)
1975 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1976 					1, buf, conn);
1977 
1978 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1979 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1980 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1981 	conn->sess->init_task_tag = cmd->init_task_tag	= hdr->itt;
1982 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1983 	cmd->cmd_sn		= hdr->cmdsn;
1984 	cmd->exp_stat_sn	= hdr->exp_statsn;
1985 	cmd->data_direction	= DMA_NONE;
1986 
1987 	spin_lock_bh(&conn->cmd_lock);
1988 	list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
1989 	spin_unlock_bh(&conn->cmd_lock);
1990 
1991 	iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
1992 
1993 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1994 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
1995 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1996 			return iscsit_add_reject_from_cmd(
1997 					ISCSI_REASON_PROTOCOL_ERROR,
1998 					1, 0, buf, cmd);
1999 
2000 		return 0;
2001 	}
2002 
2003 	return iscsit_execute_cmd(cmd, 0);
2004 }
2005 
2006 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2007 {
2008 	struct iscsi_conn *conn_p;
2009 	struct iscsi_session *sess = conn->sess;
2010 
2011 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2012 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2013 
2014 	atomic_set(&sess->session_logout, 1);
2015 	atomic_set(&conn->conn_logout_remove, 1);
2016 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2017 
2018 	iscsit_inc_conn_usage_count(conn);
2019 	iscsit_inc_session_usage_count(sess);
2020 
2021 	spin_lock_bh(&sess->conn_lock);
2022 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2023 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2024 			continue;
2025 
2026 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2027 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2028 	}
2029 	spin_unlock_bh(&sess->conn_lock);
2030 
2031 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2032 
2033 	return 0;
2034 }
2035 
2036 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2037 {
2038 	struct iscsi_conn *l_conn;
2039 	struct iscsi_session *sess = conn->sess;
2040 
2041 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2042 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2043 
2044 	/*
2045 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2046 	 * can arrive on a connection with a differing CID.
2047 	 */
2048 	if (conn->cid == cmd->logout_cid) {
2049 		spin_lock_bh(&conn->state_lock);
2050 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2051 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2052 
2053 		atomic_set(&conn->conn_logout_remove, 1);
2054 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2055 		iscsit_inc_conn_usage_count(conn);
2056 
2057 		spin_unlock_bh(&conn->state_lock);
2058 	} else {
2059 		/*
2060 		 * Handle all different cid CLOSECONNECTION requests in
2061 		 * iscsit_logout_post_handler_diffcid() as to give enough
2062 		 * time for any non immediate command's CmdSN to be
2063 		 * acknowledged on the connection in question.
2064 		 *
2065 		 * Here we simply make sure the CID is still around.
2066 		 */
2067 		l_conn = iscsit_get_conn_from_cid(sess,
2068 				cmd->logout_cid);
2069 		if (!l_conn) {
2070 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2071 			iscsit_add_cmd_to_response_queue(cmd, conn,
2072 					cmd->i_state);
2073 			return 0;
2074 		}
2075 
2076 		iscsit_dec_conn_usage_count(l_conn);
2077 	}
2078 
2079 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2080 
2081 	return 0;
2082 }
2083 
2084 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2085 {
2086 	struct iscsi_session *sess = conn->sess;
2087 
2088 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2089 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2090 
2091 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2092 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2093 			" while ERL!=2.\n");
2094 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2095 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2096 		return 0;
2097 	}
2098 
2099 	if (conn->cid == cmd->logout_cid) {
2100 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2101 			" with CID: %hu on CID: %hu, implementation error.\n",
2102 				cmd->logout_cid, conn->cid);
2103 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2104 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2105 		return 0;
2106 	}
2107 
2108 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2109 
2110 	return 0;
2111 }
2112 
2113 static int iscsit_handle_logout_cmd(
2114 	struct iscsi_conn *conn,
2115 	unsigned char *buf)
2116 {
2117 	int cmdsn_ret, logout_remove = 0;
2118 	u8 reason_code = 0;
2119 	struct iscsi_cmd *cmd;
2120 	struct iscsi_logout *hdr;
2121 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2122 
2123 	hdr			= (struct iscsi_logout *) buf;
2124 	reason_code		= (hdr->flags & 0x7f);
2125 	hdr->itt		= be32_to_cpu(hdr->itt);
2126 	hdr->cid		= be16_to_cpu(hdr->cid);
2127 	hdr->cmdsn		= be32_to_cpu(hdr->cmdsn);
2128 	hdr->exp_statsn	= be32_to_cpu(hdr->exp_statsn);
2129 
2130 	if (tiqn) {
2131 		spin_lock(&tiqn->logout_stats.lock);
2132 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2133 			tiqn->logout_stats.normal_logouts++;
2134 		else
2135 			tiqn->logout_stats.abnormal_logouts++;
2136 		spin_unlock(&tiqn->logout_stats.lock);
2137 	}
2138 
2139 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2140 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2141 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2142 		hdr->cid, conn->cid);
2143 
2144 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2145 		pr_err("Received logout request on connection that"
2146 			" is not in logged in state, ignoring request.\n");
2147 		return 0;
2148 	}
2149 
2150 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
2151 	if (!cmd)
2152 		return iscsit_add_reject(ISCSI_REASON_BOOKMARK_NO_RESOURCES, 1,
2153 					buf, conn);
2154 
2155 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2156 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2157 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2158 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2159 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2160 	cmd->cmd_sn             = hdr->cmdsn;
2161 	cmd->exp_stat_sn        = hdr->exp_statsn;
2162 	cmd->logout_cid         = hdr->cid;
2163 	cmd->logout_reason      = reason_code;
2164 	cmd->data_direction     = DMA_NONE;
2165 
2166 	/*
2167 	 * We need to sleep in these cases (by returning 1) until the Logout
2168 	 * Response gets sent in the tx thread.
2169 	 */
2170 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2171 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2172 	    (hdr->cid == conn->cid)))
2173 		logout_remove = 1;
2174 
2175 	spin_lock_bh(&conn->cmd_lock);
2176 	list_add_tail(&cmd->i_list, &conn->conn_cmd_list);
2177 	spin_unlock_bh(&conn->cmd_lock);
2178 
2179 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2180 		iscsit_ack_from_expstatsn(conn, hdr->exp_statsn);
2181 
2182 	/*
2183 	 * Immediate commands are executed, well, immediately.
2184 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2185 	 */
2186 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
2187 		int ret = iscsit_execute_cmd(cmd, 0);
2188 
2189 		if (ret < 0)
2190 			return ret;
2191 	} else {
2192 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, hdr->cmdsn);
2193 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2194 			logout_remove = 0;
2195 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2196 			return iscsit_add_reject_from_cmd(
2197 				ISCSI_REASON_PROTOCOL_ERROR,
2198 				1, 0, buf, cmd);
2199 		}
2200 	}
2201 
2202 	return logout_remove;
2203 }
2204 
2205 static int iscsit_handle_snack(
2206 	struct iscsi_conn *conn,
2207 	unsigned char *buf)
2208 {
2209 	u32 unpacked_lun;
2210 	u64 lun;
2211 	struct iscsi_snack *hdr;
2212 
2213 	hdr			= (struct iscsi_snack *) buf;
2214 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2215 	lun			= get_unaligned_le64(&hdr->lun);
2216 	unpacked_lun		= scsilun_to_int((struct scsi_lun *)&lun);
2217 	hdr->itt		= be32_to_cpu(hdr->itt);
2218 	hdr->ttt		= be32_to_cpu(hdr->ttt);
2219 	hdr->exp_statsn		= be32_to_cpu(hdr->exp_statsn);
2220 	hdr->begrun		= be32_to_cpu(hdr->begrun);
2221 	hdr->runlength		= be32_to_cpu(hdr->runlength);
2222 
2223 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2224 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2225 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2226 			hdr->begrun, hdr->runlength, conn->cid);
2227 
2228 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2229 		pr_err("Initiator sent SNACK request while in"
2230 			" ErrorRecoveryLevel=0.\n");
2231 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2232 					buf, conn);
2233 	}
2234 	/*
2235 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2236 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2237 	 */
2238 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2239 	case 0:
2240 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2241 			hdr->itt, hdr->ttt, hdr->begrun, hdr->runlength);
2242 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2243 		return iscsit_handle_status_snack(conn, hdr->itt, hdr->ttt,
2244 			hdr->begrun, hdr->runlength);
2245 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2246 		return iscsit_handle_data_ack(conn, hdr->ttt, hdr->begrun,
2247 			hdr->runlength);
2248 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2249 		/* FIXME: Support R-Data SNACK */
2250 		pr_err("R-Data SNACK Not Supported.\n");
2251 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2252 					buf, conn);
2253 	default:
2254 		pr_err("Unknown SNACK type 0x%02x, protocol"
2255 			" error.\n", hdr->flags & 0x0f);
2256 		return iscsit_add_reject(ISCSI_REASON_PROTOCOL_ERROR, 1,
2257 					buf, conn);
2258 	}
2259 
2260 	return 0;
2261 }
2262 
2263 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2264 {
2265 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2266 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2267 		wait_for_completion_interruptible_timeout(
2268 					&conn->rx_half_close_comp,
2269 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2270 	}
2271 }
2272 
2273 static int iscsit_handle_immediate_data(
2274 	struct iscsi_cmd *cmd,
2275 	unsigned char *buf,
2276 	u32 length)
2277 {
2278 	int iov_ret, rx_got = 0, rx_size = 0;
2279 	u32 checksum, iov_count = 0, padding = 0;
2280 	struct iscsi_conn *conn = cmd->conn;
2281 	struct kvec *iov;
2282 
2283 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2284 	if (iov_ret < 0)
2285 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2286 
2287 	rx_size = length;
2288 	iov_count = iov_ret;
2289 	iov = &cmd->iov_data[0];
2290 
2291 	padding = ((-length) & 3);
2292 	if (padding != 0) {
2293 		iov[iov_count].iov_base	= cmd->pad_bytes;
2294 		iov[iov_count++].iov_len = padding;
2295 		rx_size += padding;
2296 	}
2297 
2298 	if (conn->conn_ops->DataDigest) {
2299 		iov[iov_count].iov_base		= &checksum;
2300 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2301 		rx_size += ISCSI_CRC_LEN;
2302 	}
2303 
2304 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2305 
2306 	iscsit_unmap_iovec(cmd);
2307 
2308 	if (rx_got != rx_size) {
2309 		iscsit_rx_thread_wait_for_tcp(conn);
2310 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2311 	}
2312 
2313 	if (conn->conn_ops->DataDigest) {
2314 		u32 data_crc;
2315 
2316 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2317 						    cmd->write_data_done, length, padding,
2318 						    cmd->pad_bytes);
2319 
2320 		if (checksum != data_crc) {
2321 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2322 				" does not match computed 0x%08x\n", checksum,
2323 				data_crc);
2324 
2325 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2326 				pr_err("Unable to recover from"
2327 					" Immediate Data digest failure while"
2328 					" in ERL=0.\n");
2329 				iscsit_add_reject_from_cmd(
2330 						ISCSI_REASON_DATA_DIGEST_ERROR,
2331 						1, 0, buf, cmd);
2332 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2333 			} else {
2334 				iscsit_add_reject_from_cmd(
2335 						ISCSI_REASON_DATA_DIGEST_ERROR,
2336 						0, 0, buf, cmd);
2337 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2338 			}
2339 		} else {
2340 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2341 				" %u bytes of Immediate Data\n", checksum,
2342 				length);
2343 		}
2344 	}
2345 
2346 	cmd->write_data_done += length;
2347 
2348 	if (cmd->write_data_done == cmd->data_length) {
2349 		spin_lock_bh(&cmd->istate_lock);
2350 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2351 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2352 		spin_unlock_bh(&cmd->istate_lock);
2353 	}
2354 
2355 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2356 }
2357 
2358 /*
2359  *	Called with sess->conn_lock held.
2360  */
2361 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2362 	with active network interface */
2363 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2364 {
2365 	struct iscsi_cmd *cmd;
2366 	struct iscsi_conn *conn_p;
2367 
2368 	/*
2369 	 * Only send a Asynchronous Message on connections whos network
2370 	 * interface is still functional.
2371 	 */
2372 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2373 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2374 			iscsit_inc_conn_usage_count(conn_p);
2375 			break;
2376 		}
2377 	}
2378 
2379 	if (!conn_p)
2380 		return;
2381 
2382 	cmd = iscsit_allocate_cmd(conn_p, GFP_KERNEL);
2383 	if (!cmd) {
2384 		iscsit_dec_conn_usage_count(conn_p);
2385 		return;
2386 	}
2387 
2388 	cmd->logout_cid = conn->cid;
2389 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2390 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2391 
2392 	spin_lock_bh(&conn_p->cmd_lock);
2393 	list_add_tail(&cmd->i_list, &conn_p->conn_cmd_list);
2394 	spin_unlock_bh(&conn_p->cmd_lock);
2395 
2396 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2397 	iscsit_dec_conn_usage_count(conn_p);
2398 }
2399 
2400 static int iscsit_send_conn_drop_async_message(
2401 	struct iscsi_cmd *cmd,
2402 	struct iscsi_conn *conn)
2403 {
2404 	struct iscsi_async *hdr;
2405 
2406 	cmd->tx_size = ISCSI_HDR_LEN;
2407 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2408 
2409 	hdr			= (struct iscsi_async *) cmd->pdu;
2410 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2411 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2412 	cmd->init_task_tag	= 0xFFFFFFFF;
2413 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2414 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2415 	cmd->stat_sn		= conn->stat_sn++;
2416 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2417 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2418 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2419 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2420 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2421 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2422 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2423 
2424 	if (conn->conn_ops->HeaderDigest) {
2425 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2426 
2427 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2428 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2429 				0, NULL, (u8 *)header_digest);
2430 
2431 		cmd->tx_size += ISCSI_CRC_LEN;
2432 		pr_debug("Attaching CRC32C HeaderDigest to"
2433 			" Async Message 0x%08x\n", *header_digest);
2434 	}
2435 
2436 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2437 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2438 	cmd->iov_misc_count		= 1;
2439 
2440 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2441 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2442 			cmd->logout_cid, conn->cid);
2443 	return 0;
2444 }
2445 
2446 static int iscsit_send_data_in(
2447 	struct iscsi_cmd *cmd,
2448 	struct iscsi_conn *conn,
2449 	int *eodr)
2450 {
2451 	int iov_ret = 0, set_statsn = 0;
2452 	u32 iov_count = 0, tx_size = 0;
2453 	struct iscsi_datain datain;
2454 	struct iscsi_datain_req *dr;
2455 	struct iscsi_data_rsp *hdr;
2456 	struct kvec *iov;
2457 
2458 	memset(&datain, 0, sizeof(struct iscsi_datain));
2459 	dr = iscsit_get_datain_values(cmd, &datain);
2460 	if (!dr) {
2461 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2462 				cmd->init_task_tag);
2463 		return -1;
2464 	}
2465 
2466 	/*
2467 	 * Be paranoid and double check the logic for now.
2468 	 */
2469 	if ((datain.offset + datain.length) > cmd->data_length) {
2470 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2471 			" datain.length: %u exceeds cmd->data_length: %u\n",
2472 			cmd->init_task_tag, datain.offset, datain.length,
2473 				cmd->data_length);
2474 		return -1;
2475 	}
2476 
2477 	spin_lock_bh(&conn->sess->session_stats_lock);
2478 	conn->sess->tx_data_octets += datain.length;
2479 	if (conn->sess->se_sess->se_node_acl) {
2480 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
2481 		conn->sess->se_sess->se_node_acl->read_bytes += datain.length;
2482 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
2483 	}
2484 	spin_unlock_bh(&conn->sess->session_stats_lock);
2485 	/*
2486 	 * Special case for successfully execution w/ both DATAIN
2487 	 * and Sense Data.
2488 	 */
2489 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2490 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2491 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2492 	else {
2493 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2494 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2495 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2496 			cmd->stat_sn = conn->stat_sn++;
2497 			set_statsn = 1;
2498 		} else if (dr->dr_complete ==
2499 				DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2500 			set_statsn = 1;
2501 	}
2502 
2503 	hdr	= (struct iscsi_data_rsp *) cmd->pdu;
2504 	memset(hdr, 0, ISCSI_HDR_LEN);
2505 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2506 	hdr->flags		= datain.flags;
2507 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2508 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2509 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2510 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2511 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2512 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2513 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2514 		}
2515 	}
2516 	hton24(hdr->dlength, datain.length);
2517 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2518 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2519 				(struct scsi_lun *)&hdr->lun);
2520 	else
2521 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2522 
2523 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2524 	hdr->ttt		= (hdr->flags & ISCSI_FLAG_DATA_ACK) ?
2525 				   cpu_to_be32(cmd->targ_xfer_tag) :
2526 				   0xFFFFFFFF;
2527 	hdr->statsn		= (set_statsn) ? cpu_to_be32(cmd->stat_sn) :
2528 						0xFFFFFFFF;
2529 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2530 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2531 	hdr->datasn		= cpu_to_be32(datain.data_sn);
2532 	hdr->offset		= cpu_to_be32(datain.offset);
2533 
2534 	iov = &cmd->iov_data[0];
2535 	iov[iov_count].iov_base	= cmd->pdu;
2536 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2537 	tx_size += ISCSI_HDR_LEN;
2538 
2539 	if (conn->conn_ops->HeaderDigest) {
2540 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2541 
2542 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2543 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2544 				0, NULL, (u8 *)header_digest);
2545 
2546 		iov[0].iov_len += ISCSI_CRC_LEN;
2547 		tx_size += ISCSI_CRC_LEN;
2548 
2549 		pr_debug("Attaching CRC32 HeaderDigest"
2550 			" for DataIN PDU 0x%08x\n", *header_digest);
2551 	}
2552 
2553 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1], datain.offset, datain.length);
2554 	if (iov_ret < 0)
2555 		return -1;
2556 
2557 	iov_count += iov_ret;
2558 	tx_size += datain.length;
2559 
2560 	cmd->padding = ((-datain.length) & 3);
2561 	if (cmd->padding) {
2562 		iov[iov_count].iov_base		= cmd->pad_bytes;
2563 		iov[iov_count++].iov_len	= cmd->padding;
2564 		tx_size += cmd->padding;
2565 
2566 		pr_debug("Attaching %u padding bytes\n",
2567 				cmd->padding);
2568 	}
2569 	if (conn->conn_ops->DataDigest) {
2570 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2571 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2572 
2573 		iov[iov_count].iov_base	= &cmd->data_crc;
2574 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2575 		tx_size += ISCSI_CRC_LEN;
2576 
2577 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2578 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2579 	}
2580 
2581 	cmd->iov_data_count = iov_count;
2582 	cmd->tx_size = tx_size;
2583 
2584 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2585 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2586 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2587 		ntohl(hdr->offset), datain.length, conn->cid);
2588 
2589 	if (dr->dr_complete) {
2590 		*eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2591 				2 : 1;
2592 		iscsit_free_datain_req(cmd, dr);
2593 	}
2594 
2595 	return 0;
2596 }
2597 
2598 static int iscsit_send_logout_response(
2599 	struct iscsi_cmd *cmd,
2600 	struct iscsi_conn *conn)
2601 {
2602 	int niov = 0, tx_size;
2603 	struct iscsi_conn *logout_conn = NULL;
2604 	struct iscsi_conn_recovery *cr = NULL;
2605 	struct iscsi_session *sess = conn->sess;
2606 	struct kvec *iov;
2607 	struct iscsi_logout_rsp *hdr;
2608 	/*
2609 	 * The actual shutting down of Sessions and/or Connections
2610 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2611 	 * is done in scsi_logout_post_handler().
2612 	 */
2613 	switch (cmd->logout_reason) {
2614 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2615 		pr_debug("iSCSI session logout successful, setting"
2616 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2617 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2618 		break;
2619 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2620 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2621 			break;
2622 		/*
2623 		 * For CLOSECONNECTION logout requests carrying
2624 		 * a matching logout CID -> local CID, the reference
2625 		 * for the local CID will have been incremented in
2626 		 * iscsi_logout_closeconnection().
2627 		 *
2628 		 * For CLOSECONNECTION logout requests carrying
2629 		 * a different CID than the connection it arrived
2630 		 * on, the connection responding to cmd->logout_cid
2631 		 * is stopped in iscsit_logout_post_handler_diffcid().
2632 		 */
2633 
2634 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2635 			" successful.\n", cmd->logout_cid, conn->cid);
2636 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2637 		break;
2638 	case ISCSI_LOGOUT_REASON_RECOVERY:
2639 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2640 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2641 			break;
2642 		/*
2643 		 * If the connection is still active from our point of view
2644 		 * force connection recovery to occur.
2645 		 */
2646 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2647 				cmd->logout_cid);
2648 		if ((logout_conn)) {
2649 			iscsit_connection_reinstatement_rcfr(logout_conn);
2650 			iscsit_dec_conn_usage_count(logout_conn);
2651 		}
2652 
2653 		cr = iscsit_get_inactive_connection_recovery_entry(
2654 				conn->sess, cmd->logout_cid);
2655 		if (!cr) {
2656 			pr_err("Unable to locate CID: %hu for"
2657 			" REMOVECONNFORRECOVERY Logout Request.\n",
2658 				cmd->logout_cid);
2659 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2660 			break;
2661 		}
2662 
2663 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2664 
2665 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2666 			" for recovery for CID: %hu on CID: %hu successful.\n",
2667 				cmd->logout_cid, conn->cid);
2668 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2669 		break;
2670 	default:
2671 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2672 				cmd->logout_reason);
2673 		return -1;
2674 	}
2675 
2676 	tx_size = ISCSI_HDR_LEN;
2677 	hdr			= (struct iscsi_logout_rsp *)cmd->pdu;
2678 	memset(hdr, 0, ISCSI_HDR_LEN);
2679 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2680 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2681 	hdr->response		= cmd->logout_response;
2682 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2683 	cmd->stat_sn		= conn->stat_sn++;
2684 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2685 
2686 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2687 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2688 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2689 
2690 	iov = &cmd->iov_misc[0];
2691 	iov[niov].iov_base	= cmd->pdu;
2692 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2693 
2694 	if (conn->conn_ops->HeaderDigest) {
2695 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2696 
2697 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2698 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2699 				0, NULL, (u8 *)header_digest);
2700 
2701 		iov[0].iov_len += ISCSI_CRC_LEN;
2702 		tx_size += ISCSI_CRC_LEN;
2703 		pr_debug("Attaching CRC32C HeaderDigest to"
2704 			" Logout Response 0x%08x\n", *header_digest);
2705 	}
2706 	cmd->iov_misc_count = niov;
2707 	cmd->tx_size = tx_size;
2708 
2709 	pr_debug("Sending Logout Response ITT: 0x%08x StatSN:"
2710 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2711 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2712 		cmd->logout_cid, conn->cid);
2713 
2714 	return 0;
2715 }
2716 
2717 /*
2718  *	Unsolicited NOPIN, either requesting a response or not.
2719  */
2720 static int iscsit_send_unsolicited_nopin(
2721 	struct iscsi_cmd *cmd,
2722 	struct iscsi_conn *conn,
2723 	int want_response)
2724 {
2725 	int tx_size = ISCSI_HDR_LEN;
2726 	struct iscsi_nopin *hdr;
2727 
2728 	hdr			= (struct iscsi_nopin *) cmd->pdu;
2729 	memset(hdr, 0, ISCSI_HDR_LEN);
2730 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2731 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2732 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2733 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2734 	cmd->stat_sn		= conn->stat_sn;
2735 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2736 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2737 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2738 
2739 	if (conn->conn_ops->HeaderDigest) {
2740 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2741 
2742 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2743 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2744 				0, NULL, (u8 *)header_digest);
2745 
2746 		tx_size += ISCSI_CRC_LEN;
2747 		pr_debug("Attaching CRC32C HeaderDigest to"
2748 			" NopIN 0x%08x\n", *header_digest);
2749 	}
2750 
2751 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2752 	cmd->iov_misc[0].iov_len	= tx_size;
2753 	cmd->iov_misc_count	= 1;
2754 	cmd->tx_size		= tx_size;
2755 
2756 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2757 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2758 
2759 	return 0;
2760 }
2761 
2762 static int iscsit_send_nopin_response(
2763 	struct iscsi_cmd *cmd,
2764 	struct iscsi_conn *conn)
2765 {
2766 	int niov = 0, tx_size;
2767 	u32 padding = 0;
2768 	struct kvec *iov;
2769 	struct iscsi_nopin *hdr;
2770 
2771 	tx_size = ISCSI_HDR_LEN;
2772 	hdr			= (struct iscsi_nopin *) cmd->pdu;
2773 	memset(hdr, 0, ISCSI_HDR_LEN);
2774 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2775 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2776 	hton24(hdr->dlength, cmd->buf_ptr_size);
2777 	put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2778 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2779 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2780 	cmd->stat_sn		= conn->stat_sn++;
2781 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2782 
2783 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2784 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2785 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2786 
2787 	iov = &cmd->iov_misc[0];
2788 	iov[niov].iov_base	= cmd->pdu;
2789 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2790 
2791 	if (conn->conn_ops->HeaderDigest) {
2792 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2793 
2794 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2795 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2796 				0, NULL, (u8 *)header_digest);
2797 
2798 		iov[0].iov_len += ISCSI_CRC_LEN;
2799 		tx_size += ISCSI_CRC_LEN;
2800 		pr_debug("Attaching CRC32C HeaderDigest"
2801 			" to NopIn 0x%08x\n", *header_digest);
2802 	}
2803 
2804 	/*
2805 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2806 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2807 	 */
2808 	if (cmd->buf_ptr_size) {
2809 		iov[niov].iov_base	= cmd->buf_ptr;
2810 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2811 		tx_size += cmd->buf_ptr_size;
2812 
2813 		pr_debug("Echoing back %u bytes of ping"
2814 			" data.\n", cmd->buf_ptr_size);
2815 
2816 		padding = ((-cmd->buf_ptr_size) & 3);
2817 		if (padding != 0) {
2818 			iov[niov].iov_base = &cmd->pad_bytes;
2819 			iov[niov++].iov_len = padding;
2820 			tx_size += padding;
2821 			pr_debug("Attaching %u additional"
2822 				" padding bytes.\n", padding);
2823 		}
2824 		if (conn->conn_ops->DataDigest) {
2825 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2826 				cmd->buf_ptr, cmd->buf_ptr_size,
2827 				padding, (u8 *)&cmd->pad_bytes,
2828 				(u8 *)&cmd->data_crc);
2829 
2830 			iov[niov].iov_base = &cmd->data_crc;
2831 			iov[niov++].iov_len = ISCSI_CRC_LEN;
2832 			tx_size += ISCSI_CRC_LEN;
2833 			pr_debug("Attached DataDigest for %u"
2834 				" bytes of ping data, CRC 0x%08x\n",
2835 				cmd->buf_ptr_size, cmd->data_crc);
2836 		}
2837 	}
2838 
2839 	cmd->iov_misc_count = niov;
2840 	cmd->tx_size = tx_size;
2841 
2842 	pr_debug("Sending NOPIN Response ITT: 0x%08x, TTT:"
2843 		" 0x%08x, StatSN: 0x%08x, Length %u\n", cmd->init_task_tag,
2844 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2845 
2846 	return 0;
2847 }
2848 
2849 int iscsit_send_r2t(
2850 	struct iscsi_cmd *cmd,
2851 	struct iscsi_conn *conn)
2852 {
2853 	int tx_size = 0;
2854 	struct iscsi_r2t *r2t;
2855 	struct iscsi_r2t_rsp *hdr;
2856 
2857 	r2t = iscsit_get_r2t_from_list(cmd);
2858 	if (!r2t)
2859 		return -1;
2860 
2861 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
2862 	memset(hdr, 0, ISCSI_HDR_LEN);
2863 	hdr->opcode		= ISCSI_OP_R2T;
2864 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2865 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2866 			(struct scsi_lun *)&hdr->lun);
2867 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
2868 	spin_lock_bh(&conn->sess->ttt_lock);
2869 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
2870 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
2871 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
2872 	spin_unlock_bh(&conn->sess->ttt_lock);
2873 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
2874 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
2875 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2876 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2877 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
2878 	hdr->data_offset	= cpu_to_be32(r2t->offset);
2879 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
2880 
2881 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2882 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
2883 	tx_size += ISCSI_HDR_LEN;
2884 
2885 	if (conn->conn_ops->HeaderDigest) {
2886 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2887 
2888 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2889 				(unsigned char *)hdr, ISCSI_HDR_LEN,
2890 				0, NULL, (u8 *)header_digest);
2891 
2892 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
2893 		tx_size += ISCSI_CRC_LEN;
2894 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
2895 			" PDU 0x%08x\n", *header_digest);
2896 	}
2897 
2898 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
2899 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
2900 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
2901 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
2902 			r2t->offset, r2t->xfer_len, conn->cid);
2903 
2904 	cmd->iov_misc_count = 1;
2905 	cmd->tx_size = tx_size;
2906 
2907 	spin_lock_bh(&cmd->r2t_lock);
2908 	r2t->sent_r2t = 1;
2909 	spin_unlock_bh(&cmd->r2t_lock);
2910 
2911 	return 0;
2912 }
2913 
2914 /*
2915  *	type 0: Normal Operation.
2916  *	type 1: Called from Storage Transport.
2917  *	type 2: Called from iscsi_task_reassign_complete_write() for
2918  *	        connection recovery.
2919  */
2920 int iscsit_build_r2ts_for_cmd(
2921 	struct iscsi_cmd *cmd,
2922 	struct iscsi_conn *conn,
2923 	int type)
2924 {
2925 	int first_r2t = 1;
2926 	u32 offset = 0, xfer_len = 0;
2927 
2928 	spin_lock_bh(&cmd->r2t_lock);
2929 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
2930 		spin_unlock_bh(&cmd->r2t_lock);
2931 		return 0;
2932 	}
2933 
2934 	if (conn->sess->sess_ops->DataSequenceInOrder && (type != 2))
2935 		if (cmd->r2t_offset < cmd->write_data_done)
2936 			cmd->r2t_offset = cmd->write_data_done;
2937 
2938 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
2939 		if (conn->sess->sess_ops->DataSequenceInOrder) {
2940 			offset = cmd->r2t_offset;
2941 
2942 			if (first_r2t && (type == 2)) {
2943 				xfer_len = ((offset +
2944 					     (conn->sess->sess_ops->MaxBurstLength -
2945 					     cmd->next_burst_len) >
2946 					     cmd->data_length) ?
2947 					    (cmd->data_length - offset) :
2948 					    (conn->sess->sess_ops->MaxBurstLength -
2949 					     cmd->next_burst_len));
2950 			} else {
2951 				xfer_len = ((offset +
2952 					     conn->sess->sess_ops->MaxBurstLength) >
2953 					     cmd->data_length) ?
2954 					     (cmd->data_length - offset) :
2955 					     conn->sess->sess_ops->MaxBurstLength;
2956 			}
2957 			cmd->r2t_offset += xfer_len;
2958 
2959 			if (cmd->r2t_offset == cmd->data_length)
2960 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
2961 		} else {
2962 			struct iscsi_seq *seq;
2963 
2964 			seq = iscsit_get_seq_holder_for_r2t(cmd);
2965 			if (!seq) {
2966 				spin_unlock_bh(&cmd->r2t_lock);
2967 				return -1;
2968 			}
2969 
2970 			offset = seq->offset;
2971 			xfer_len = seq->xfer_len;
2972 
2973 			if (cmd->seq_send_order == cmd->seq_count)
2974 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
2975 		}
2976 		cmd->outstanding_r2ts++;
2977 		first_r2t = 0;
2978 
2979 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
2980 			spin_unlock_bh(&cmd->r2t_lock);
2981 			return -1;
2982 		}
2983 
2984 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
2985 			break;
2986 	}
2987 	spin_unlock_bh(&cmd->r2t_lock);
2988 
2989 	return 0;
2990 }
2991 
2992 static int iscsit_send_status(
2993 	struct iscsi_cmd *cmd,
2994 	struct iscsi_conn *conn)
2995 {
2996 	u8 iov_count = 0, recovery;
2997 	u32 padding = 0, tx_size = 0;
2998 	struct iscsi_scsi_rsp *hdr;
2999 	struct kvec *iov;
3000 
3001 	recovery = (cmd->i_state != ISTATE_SEND_STATUS);
3002 	if (!recovery)
3003 		cmd->stat_sn = conn->stat_sn++;
3004 
3005 	spin_lock_bh(&conn->sess->session_stats_lock);
3006 	conn->sess->rsp_pdus++;
3007 	spin_unlock_bh(&conn->sess->session_stats_lock);
3008 
3009 	hdr			= (struct iscsi_scsi_rsp *) cmd->pdu;
3010 	memset(hdr, 0, ISCSI_HDR_LEN);
3011 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3012 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3013 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3014 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3015 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3016 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3017 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3018 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3019 	}
3020 	hdr->response		= cmd->iscsi_response;
3021 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3022 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3023 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3024 
3025 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3026 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3027 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3028 
3029 	iov = &cmd->iov_misc[0];
3030 	iov[iov_count].iov_base	= cmd->pdu;
3031 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3032 	tx_size += ISCSI_HDR_LEN;
3033 
3034 	/*
3035 	 * Attach SENSE DATA payload to iSCSI Response PDU
3036 	 */
3037 	if (cmd->se_cmd.sense_buffer &&
3038 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3039 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3040 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3041 		hton24(hdr->dlength, cmd->se_cmd.scsi_sense_length);
3042 		iov[iov_count].iov_base	= cmd->se_cmd.sense_buffer;
3043 		iov[iov_count++].iov_len =
3044 				(cmd->se_cmd.scsi_sense_length + padding);
3045 		tx_size += cmd->se_cmd.scsi_sense_length;
3046 
3047 		if (padding) {
3048 			memset(cmd->se_cmd.sense_buffer +
3049 				cmd->se_cmd.scsi_sense_length, 0, padding);
3050 			tx_size += padding;
3051 			pr_debug("Adding %u bytes of padding to"
3052 				" SENSE.\n", padding);
3053 		}
3054 
3055 		if (conn->conn_ops->DataDigest) {
3056 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3057 				cmd->se_cmd.sense_buffer,
3058 				(cmd->se_cmd.scsi_sense_length + padding),
3059 				0, NULL, (u8 *)&cmd->data_crc);
3060 
3061 			iov[iov_count].iov_base    = &cmd->data_crc;
3062 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3063 			tx_size += ISCSI_CRC_LEN;
3064 
3065 			pr_debug("Attaching CRC32 DataDigest for"
3066 				" SENSE, %u bytes CRC 0x%08x\n",
3067 				(cmd->se_cmd.scsi_sense_length + padding),
3068 				cmd->data_crc);
3069 		}
3070 
3071 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3072 				" Response PDU\n",
3073 				cmd->se_cmd.scsi_sense_length);
3074 	}
3075 
3076 	if (conn->conn_ops->HeaderDigest) {
3077 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3078 
3079 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3080 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3081 				0, NULL, (u8 *)header_digest);
3082 
3083 		iov[0].iov_len += ISCSI_CRC_LEN;
3084 		tx_size += ISCSI_CRC_LEN;
3085 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3086 				" PDU 0x%08x\n", *header_digest);
3087 	}
3088 
3089 	cmd->iov_misc_count = iov_count;
3090 	cmd->tx_size = tx_size;
3091 
3092 	pr_debug("Built %sSCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3093 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3094 		(!recovery) ? "" : "Recovery ", cmd->init_task_tag,
3095 		cmd->stat_sn, 0x00, cmd->se_cmd.scsi_status, conn->cid);
3096 
3097 	return 0;
3098 }
3099 
3100 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3101 {
3102 	switch (se_tmr->response) {
3103 	case TMR_FUNCTION_COMPLETE:
3104 		return ISCSI_TMF_RSP_COMPLETE;
3105 	case TMR_TASK_DOES_NOT_EXIST:
3106 		return ISCSI_TMF_RSP_NO_TASK;
3107 	case TMR_LUN_DOES_NOT_EXIST:
3108 		return ISCSI_TMF_RSP_NO_LUN;
3109 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3110 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3111 	case TMR_FUNCTION_AUTHORIZATION_FAILED:
3112 		return ISCSI_TMF_RSP_AUTH_FAILED;
3113 	case TMR_FUNCTION_REJECTED:
3114 	default:
3115 		return ISCSI_TMF_RSP_REJECTED;
3116 	}
3117 }
3118 
3119 static int iscsit_send_task_mgt_rsp(
3120 	struct iscsi_cmd *cmd,
3121 	struct iscsi_conn *conn)
3122 {
3123 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3124 	struct iscsi_tm_rsp *hdr;
3125 	u32 tx_size = 0;
3126 
3127 	hdr			= (struct iscsi_tm_rsp *) cmd->pdu;
3128 	memset(hdr, 0, ISCSI_HDR_LEN);
3129 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3130 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3131 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3132 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3133 	cmd->stat_sn		= conn->stat_sn++;
3134 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3135 
3136 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3137 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3138 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3139 
3140 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3141 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3142 	tx_size += ISCSI_HDR_LEN;
3143 
3144 	if (conn->conn_ops->HeaderDigest) {
3145 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3146 
3147 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3148 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3149 				0, NULL, (u8 *)header_digest);
3150 
3151 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3152 		tx_size += ISCSI_CRC_LEN;
3153 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3154 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3155 	}
3156 
3157 	cmd->iov_misc_count = 1;
3158 	cmd->tx_size = tx_size;
3159 
3160 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3161 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3162 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3163 
3164 	return 0;
3165 }
3166 
3167 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3168 {
3169 	char *payload = NULL;
3170 	struct iscsi_conn *conn = cmd->conn;
3171 	struct iscsi_portal_group *tpg;
3172 	struct iscsi_tiqn *tiqn;
3173 	struct iscsi_tpg_np *tpg_np;
3174 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3175 	unsigned char buf[256];
3176 
3177 	buffer_len = (conn->conn_ops->MaxRecvDataSegmentLength > 32768) ?
3178 			32768 : conn->conn_ops->MaxRecvDataSegmentLength;
3179 
3180 	memset(buf, 0, 256);
3181 
3182 	payload = kzalloc(buffer_len, GFP_KERNEL);
3183 	if (!payload) {
3184 		pr_err("Unable to allocate memory for sendtargets"
3185 				" response.\n");
3186 		return -ENOMEM;
3187 	}
3188 
3189 	spin_lock(&tiqn_lock);
3190 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3191 		len = sprintf(buf, "TargetName=%s", tiqn->tiqn);
3192 		len += 1;
3193 
3194 		if ((len + payload_len) > buffer_len) {
3195 			spin_unlock(&tiqn->tiqn_tpg_lock);
3196 			end_of_buf = 1;
3197 			goto eob;
3198 		}
3199 		memcpy(payload + payload_len, buf, len);
3200 		payload_len += len;
3201 
3202 		spin_lock(&tiqn->tiqn_tpg_lock);
3203 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3204 
3205 			spin_lock(&tpg->tpg_state_lock);
3206 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3207 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3208 				spin_unlock(&tpg->tpg_state_lock);
3209 				continue;
3210 			}
3211 			spin_unlock(&tpg->tpg_state_lock);
3212 
3213 			spin_lock(&tpg->tpg_np_lock);
3214 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3215 						tpg_np_list) {
3216 				len = sprintf(buf, "TargetAddress="
3217 					"%s%s%s:%hu,%hu",
3218 					(tpg_np->tpg_np->np_sockaddr.ss_family == AF_INET6) ?
3219 					"[" : "", tpg_np->tpg_np->np_ip,
3220 					(tpg_np->tpg_np->np_sockaddr.ss_family == AF_INET6) ?
3221 					"]" : "", tpg_np->tpg_np->np_port,
3222 					tpg->tpgt);
3223 				len += 1;
3224 
3225 				if ((len + payload_len) > buffer_len) {
3226 					spin_unlock(&tpg->tpg_np_lock);
3227 					spin_unlock(&tiqn->tiqn_tpg_lock);
3228 					end_of_buf = 1;
3229 					goto eob;
3230 				}
3231 				memcpy(payload + payload_len, buf, len);
3232 				payload_len += len;
3233 			}
3234 			spin_unlock(&tpg->tpg_np_lock);
3235 		}
3236 		spin_unlock(&tiqn->tiqn_tpg_lock);
3237 eob:
3238 		if (end_of_buf)
3239 			break;
3240 	}
3241 	spin_unlock(&tiqn_lock);
3242 
3243 	cmd->buf_ptr = payload;
3244 
3245 	return payload_len;
3246 }
3247 
3248 /*
3249  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3250  *	MaxRecvDataSegmentLength.
3251  */
3252 static int iscsit_send_text_rsp(
3253 	struct iscsi_cmd *cmd,
3254 	struct iscsi_conn *conn)
3255 {
3256 	struct iscsi_text_rsp *hdr;
3257 	struct kvec *iov;
3258 	u32 padding = 0, tx_size = 0;
3259 	int text_length, iov_count = 0;
3260 
3261 	text_length = iscsit_build_sendtargets_response(cmd);
3262 	if (text_length < 0)
3263 		return text_length;
3264 
3265 	padding = ((-text_length) & 3);
3266 	if (padding != 0) {
3267 		memset(cmd->buf_ptr + text_length, 0, padding);
3268 		pr_debug("Attaching %u additional bytes for"
3269 			" padding.\n", padding);
3270 	}
3271 
3272 	hdr			= (struct iscsi_text_rsp *) cmd->pdu;
3273 	memset(hdr, 0, ISCSI_HDR_LEN);
3274 	hdr->opcode		= ISCSI_OP_TEXT_RSP;
3275 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3276 	hton24(hdr->dlength, text_length);
3277 	hdr->itt		= cpu_to_be32(cmd->init_task_tag);
3278 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
3279 	cmd->stat_sn		= conn->stat_sn++;
3280 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3281 
3282 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3283 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3284 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3285 
3286 	iov = &cmd->iov_misc[0];
3287 
3288 	iov[iov_count].iov_base = cmd->pdu;
3289 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3290 	iov[iov_count].iov_base	= cmd->buf_ptr;
3291 	iov[iov_count++].iov_len = text_length + padding;
3292 
3293 	tx_size += (ISCSI_HDR_LEN + text_length + padding);
3294 
3295 	if (conn->conn_ops->HeaderDigest) {
3296 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3297 
3298 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3299 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3300 				0, NULL, (u8 *)header_digest);
3301 
3302 		iov[0].iov_len += ISCSI_CRC_LEN;
3303 		tx_size += ISCSI_CRC_LEN;
3304 		pr_debug("Attaching CRC32 HeaderDigest for"
3305 			" Text Response PDU 0x%08x\n", *header_digest);
3306 	}
3307 
3308 	if (conn->conn_ops->DataDigest) {
3309 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3310 				cmd->buf_ptr, (text_length + padding),
3311 				0, NULL, (u8 *)&cmd->data_crc);
3312 
3313 		iov[iov_count].iov_base	= &cmd->data_crc;
3314 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3315 		tx_size	+= ISCSI_CRC_LEN;
3316 
3317 		pr_debug("Attaching DataDigest for %u bytes of text"
3318 			" data, CRC 0x%08x\n", (text_length + padding),
3319 			cmd->data_crc);
3320 	}
3321 
3322 	cmd->iov_misc_count = iov_count;
3323 	cmd->tx_size = tx_size;
3324 
3325 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3326 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3327 			text_length, conn->cid);
3328 	return 0;
3329 }
3330 
3331 static int iscsit_send_reject(
3332 	struct iscsi_cmd *cmd,
3333 	struct iscsi_conn *conn)
3334 {
3335 	u32 iov_count = 0, tx_size = 0;
3336 	struct iscsi_reject *hdr;
3337 	struct kvec *iov;
3338 
3339 	hdr			= (struct iscsi_reject *) cmd->pdu;
3340 	hdr->opcode		= ISCSI_OP_REJECT;
3341 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3342 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3343 	cmd->stat_sn		= conn->stat_sn++;
3344 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3345 	hdr->exp_cmdsn	= cpu_to_be32(conn->sess->exp_cmd_sn);
3346 	hdr->max_cmdsn	= cpu_to_be32(conn->sess->max_cmd_sn);
3347 
3348 	iov = &cmd->iov_misc[0];
3349 
3350 	iov[iov_count].iov_base = cmd->pdu;
3351 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3352 	iov[iov_count].iov_base = cmd->buf_ptr;
3353 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3354 
3355 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3356 
3357 	if (conn->conn_ops->HeaderDigest) {
3358 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3359 
3360 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3361 				(unsigned char *)hdr, ISCSI_HDR_LEN,
3362 				0, NULL, (u8 *)header_digest);
3363 
3364 		iov[0].iov_len += ISCSI_CRC_LEN;
3365 		tx_size += ISCSI_CRC_LEN;
3366 		pr_debug("Attaching CRC32 HeaderDigest for"
3367 			" REJECT PDU 0x%08x\n", *header_digest);
3368 	}
3369 
3370 	if (conn->conn_ops->DataDigest) {
3371 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3372 				(unsigned char *)cmd->buf_ptr, ISCSI_HDR_LEN,
3373 				0, NULL, (u8 *)&cmd->data_crc);
3374 
3375 		iov[iov_count].iov_base = &cmd->data_crc;
3376 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3377 		tx_size += ISCSI_CRC_LEN;
3378 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3379 				" PDU 0x%08x\n", cmd->data_crc);
3380 	}
3381 
3382 	cmd->iov_misc_count = iov_count;
3383 	cmd->tx_size = tx_size;
3384 
3385 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3386 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3387 
3388 	return 0;
3389 }
3390 
3391 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
3392 {
3393 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
3394 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
3395 		wait_for_completion_interruptible_timeout(
3396 					&conn->tx_half_close_comp,
3397 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
3398 	}
3399 }
3400 
3401 #ifdef CONFIG_SMP
3402 
3403 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3404 {
3405 	struct iscsi_thread_set *ts = conn->thread_set;
3406 	int ord, cpu;
3407 	/*
3408 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3409 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3410 	 *
3411 	 * Here we use thread_id to determine which CPU that this
3412 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3413 	 * execute upon.
3414 	 */
3415 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3416 #if 0
3417 	pr_debug(">>>>>>>>>>>>>>>>>>>> Generated ord: %d from"
3418 			" thread_id: %d\n", ord, ts->thread_id);
3419 #endif
3420 	for_each_online_cpu(cpu) {
3421 		if (ord-- == 0) {
3422 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3423 			return;
3424 		}
3425 	}
3426 	/*
3427 	 * This should never be reached..
3428 	 */
3429 	dump_stack();
3430 	cpumask_setall(conn->conn_cpumask);
3431 }
3432 
3433 static inline void iscsit_thread_check_cpumask(
3434 	struct iscsi_conn *conn,
3435 	struct task_struct *p,
3436 	int mode)
3437 {
3438 	char buf[128];
3439 	/*
3440 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3441 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3442 	 */
3443 	if (mode == 1) {
3444 		if (!conn->conn_tx_reset_cpumask)
3445 			return;
3446 		conn->conn_tx_reset_cpumask = 0;
3447 	} else {
3448 		if (!conn->conn_rx_reset_cpumask)
3449 			return;
3450 		conn->conn_rx_reset_cpumask = 0;
3451 	}
3452 	/*
3453 	 * Update the CPU mask for this single kthread so that
3454 	 * both TX and RX kthreads are scheduled to run on the
3455 	 * same CPU.
3456 	 */
3457 	memset(buf, 0, 128);
3458 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3459 #if 0
3460 	pr_debug(">>>>>>>>>>>>>> Calling set_cpus_allowed_ptr():"
3461 			" %s for %s\n", buf, p->comm);
3462 #endif
3463 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3464 }
3465 
3466 #else
3467 
3468 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3469 {
3470 	return;
3471 }
3472 
3473 #define iscsit_thread_check_cpumask(X, Y, Z) ({})
3474 #endif /* CONFIG_SMP */
3475 
3476 int iscsi_target_tx_thread(void *arg)
3477 {
3478 	u8 state;
3479 	int eodr = 0;
3480 	int ret = 0;
3481 	int sent_status = 0;
3482 	int use_misc = 0;
3483 	int map_sg = 0;
3484 	struct iscsi_cmd *cmd = NULL;
3485 	struct iscsi_conn *conn;
3486 	struct iscsi_queue_req *qr = NULL;
3487 	struct se_cmd *se_cmd;
3488 	struct iscsi_thread_set *ts = arg;
3489 	/*
3490 	 * Allow ourselves to be interrupted by SIGINT so that a
3491 	 * connection recovery / failure event can be triggered externally.
3492 	 */
3493 	allow_signal(SIGINT);
3494 
3495 restart:
3496 	conn = iscsi_tx_thread_pre_handler(ts);
3497 	if (!conn)
3498 		goto out;
3499 
3500 	eodr = map_sg = ret = sent_status = use_misc = 0;
3501 
3502 	while (!kthread_should_stop()) {
3503 		/*
3504 		 * Ensure that both TX and RX per connection kthreads
3505 		 * are scheduled to run on the same CPU.
3506 		 */
3507 		iscsit_thread_check_cpumask(conn, current, 1);
3508 
3509 		schedule_timeout_interruptible(MAX_SCHEDULE_TIMEOUT);
3510 
3511 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3512 		     signal_pending(current))
3513 			goto transport_err;
3514 
3515 get_immediate:
3516 		qr = iscsit_get_cmd_from_immediate_queue(conn);
3517 		if (qr) {
3518 			atomic_set(&conn->check_immediate_queue, 0);
3519 			cmd = qr->cmd;
3520 			state = qr->state;
3521 			kmem_cache_free(lio_qr_cache, qr);
3522 
3523 			spin_lock_bh(&cmd->istate_lock);
3524 			switch (state) {
3525 			case ISTATE_SEND_R2T:
3526 				spin_unlock_bh(&cmd->istate_lock);
3527 				ret = iscsit_send_r2t(cmd, conn);
3528 				break;
3529 			case ISTATE_REMOVE:
3530 				spin_unlock_bh(&cmd->istate_lock);
3531 
3532 				if (cmd->data_direction == DMA_TO_DEVICE)
3533 					iscsit_stop_dataout_timer(cmd);
3534 
3535 				spin_lock_bh(&conn->cmd_lock);
3536 				list_del(&cmd->i_list);
3537 				spin_unlock_bh(&conn->cmd_lock);
3538 
3539 				iscsit_free_cmd(cmd);
3540 				goto get_immediate;
3541 			case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3542 				spin_unlock_bh(&cmd->istate_lock);
3543 				iscsit_mod_nopin_response_timer(conn);
3544 				ret = iscsit_send_unsolicited_nopin(cmd,
3545 						conn, 1);
3546 				break;
3547 			case ISTATE_SEND_NOPIN_NO_RESPONSE:
3548 				spin_unlock_bh(&cmd->istate_lock);
3549 				ret = iscsit_send_unsolicited_nopin(cmd,
3550 						conn, 0);
3551 				break;
3552 			default:
3553 				pr_err("Unknown Opcode: 0x%02x ITT:"
3554 				" 0x%08x, i_state: %d on CID: %hu\n",
3555 				cmd->iscsi_opcode, cmd->init_task_tag, state,
3556 				conn->cid);
3557 				spin_unlock_bh(&cmd->istate_lock);
3558 				goto transport_err;
3559 			}
3560 			if (ret < 0) {
3561 				conn->tx_immediate_queue = 0;
3562 				goto transport_err;
3563 			}
3564 
3565 			if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3566 				conn->tx_immediate_queue = 0;
3567 				iscsit_tx_thread_wait_for_tcp(conn);
3568 				goto transport_err;
3569 			}
3570 
3571 			spin_lock_bh(&cmd->istate_lock);
3572 			switch (state) {
3573 			case ISTATE_SEND_R2T:
3574 				spin_unlock_bh(&cmd->istate_lock);
3575 				spin_lock_bh(&cmd->dataout_timeout_lock);
3576 				iscsit_start_dataout_timer(cmd, conn);
3577 				spin_unlock_bh(&cmd->dataout_timeout_lock);
3578 				break;
3579 			case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3580 				cmd->i_state = ISTATE_SENT_NOPIN_WANT_RESPONSE;
3581 				spin_unlock_bh(&cmd->istate_lock);
3582 				break;
3583 			case ISTATE_SEND_NOPIN_NO_RESPONSE:
3584 				cmd->i_state = ISTATE_SENT_STATUS;
3585 				spin_unlock_bh(&cmd->istate_lock);
3586 				break;
3587 			default:
3588 				pr_err("Unknown Opcode: 0x%02x ITT:"
3589 					" 0x%08x, i_state: %d on CID: %hu\n",
3590 					cmd->iscsi_opcode, cmd->init_task_tag,
3591 					state, conn->cid);
3592 				spin_unlock_bh(&cmd->istate_lock);
3593 				goto transport_err;
3594 			}
3595 			goto get_immediate;
3596 		} else
3597 			conn->tx_immediate_queue = 0;
3598 
3599 get_response:
3600 		qr = iscsit_get_cmd_from_response_queue(conn);
3601 		if (qr) {
3602 			cmd = qr->cmd;
3603 			state = qr->state;
3604 			kmem_cache_free(lio_qr_cache, qr);
3605 
3606 			spin_lock_bh(&cmd->istate_lock);
3607 check_rsp_state:
3608 			switch (state) {
3609 			case ISTATE_SEND_DATAIN:
3610 				spin_unlock_bh(&cmd->istate_lock);
3611 				ret = iscsit_send_data_in(cmd, conn,
3612 							  &eodr);
3613 				map_sg = 1;
3614 				break;
3615 			case ISTATE_SEND_STATUS:
3616 			case ISTATE_SEND_STATUS_RECOVERY:
3617 				spin_unlock_bh(&cmd->istate_lock);
3618 				use_misc = 1;
3619 				ret = iscsit_send_status(cmd, conn);
3620 				break;
3621 			case ISTATE_SEND_LOGOUTRSP:
3622 				spin_unlock_bh(&cmd->istate_lock);
3623 				use_misc = 1;
3624 				ret = iscsit_send_logout_response(cmd, conn);
3625 				break;
3626 			case ISTATE_SEND_ASYNCMSG:
3627 				spin_unlock_bh(&cmd->istate_lock);
3628 				use_misc = 1;
3629 				ret = iscsit_send_conn_drop_async_message(
3630 						cmd, conn);
3631 				break;
3632 			case ISTATE_SEND_NOPIN:
3633 				spin_unlock_bh(&cmd->istate_lock);
3634 				use_misc = 1;
3635 				ret = iscsit_send_nopin_response(cmd, conn);
3636 				break;
3637 			case ISTATE_SEND_REJECT:
3638 				spin_unlock_bh(&cmd->istate_lock);
3639 				use_misc = 1;
3640 				ret = iscsit_send_reject(cmd, conn);
3641 				break;
3642 			case ISTATE_SEND_TASKMGTRSP:
3643 				spin_unlock_bh(&cmd->istate_lock);
3644 				use_misc = 1;
3645 				ret = iscsit_send_task_mgt_rsp(cmd, conn);
3646 				if (ret != 0)
3647 					break;
3648 				ret = iscsit_tmr_post_handler(cmd, conn);
3649 				if (ret != 0)
3650 					iscsit_fall_back_to_erl0(conn->sess);
3651 				break;
3652 			case ISTATE_SEND_TEXTRSP:
3653 				spin_unlock_bh(&cmd->istate_lock);
3654 				use_misc = 1;
3655 				ret = iscsit_send_text_rsp(cmd, conn);
3656 				break;
3657 			default:
3658 				pr_err("Unknown Opcode: 0x%02x ITT:"
3659 					" 0x%08x, i_state: %d on CID: %hu\n",
3660 					cmd->iscsi_opcode, cmd->init_task_tag,
3661 					state, conn->cid);
3662 				spin_unlock_bh(&cmd->istate_lock);
3663 				goto transport_err;
3664 			}
3665 			if (ret < 0) {
3666 				conn->tx_response_queue = 0;
3667 				goto transport_err;
3668 			}
3669 
3670 			se_cmd = &cmd->se_cmd;
3671 
3672 			if (map_sg && !conn->conn_ops->IFMarker) {
3673 				if (iscsit_fe_sendpage_sg(cmd, conn) < 0) {
3674 					conn->tx_response_queue = 0;
3675 					iscsit_tx_thread_wait_for_tcp(conn);
3676 					iscsit_unmap_iovec(cmd);
3677 					goto transport_err;
3678 				}
3679 			} else {
3680 				if (iscsit_send_tx_data(cmd, conn, use_misc) < 0) {
3681 					conn->tx_response_queue = 0;
3682 					iscsit_tx_thread_wait_for_tcp(conn);
3683 					iscsit_unmap_iovec(cmd);
3684 					goto transport_err;
3685 				}
3686 			}
3687 			map_sg = 0;
3688 			iscsit_unmap_iovec(cmd);
3689 
3690 			spin_lock_bh(&cmd->istate_lock);
3691 			switch (state) {
3692 			case ISTATE_SEND_DATAIN:
3693 				if (!eodr)
3694 					goto check_rsp_state;
3695 
3696 				if (eodr == 1) {
3697 					cmd->i_state = ISTATE_SENT_LAST_DATAIN;
3698 					sent_status = 1;
3699 					eodr = use_misc = 0;
3700 				} else if (eodr == 2) {
3701 					cmd->i_state = state =
3702 							ISTATE_SEND_STATUS;
3703 					sent_status = 0;
3704 					eodr = use_misc = 0;
3705 					goto check_rsp_state;
3706 				}
3707 				break;
3708 			case ISTATE_SEND_STATUS:
3709 				use_misc = 0;
3710 				sent_status = 1;
3711 				break;
3712 			case ISTATE_SEND_ASYNCMSG:
3713 			case ISTATE_SEND_NOPIN:
3714 			case ISTATE_SEND_STATUS_RECOVERY:
3715 			case ISTATE_SEND_TEXTRSP:
3716 				use_misc = 0;
3717 				sent_status = 1;
3718 				break;
3719 			case ISTATE_SEND_REJECT:
3720 				use_misc = 0;
3721 				if (cmd->cmd_flags & ICF_REJECT_FAIL_CONN) {
3722 					cmd->cmd_flags &= ~ICF_REJECT_FAIL_CONN;
3723 					spin_unlock_bh(&cmd->istate_lock);
3724 					complete(&cmd->reject_comp);
3725 					goto transport_err;
3726 				}
3727 				complete(&cmd->reject_comp);
3728 				break;
3729 			case ISTATE_SEND_TASKMGTRSP:
3730 				use_misc = 0;
3731 				sent_status = 1;
3732 				break;
3733 			case ISTATE_SEND_LOGOUTRSP:
3734 				spin_unlock_bh(&cmd->istate_lock);
3735 				if (!iscsit_logout_post_handler(cmd, conn))
3736 					goto restart;
3737 				spin_lock_bh(&cmd->istate_lock);
3738 				use_misc = 0;
3739 				sent_status = 1;
3740 				break;
3741 			default:
3742 				pr_err("Unknown Opcode: 0x%02x ITT:"
3743 					" 0x%08x, i_state: %d on CID: %hu\n",
3744 					cmd->iscsi_opcode, cmd->init_task_tag,
3745 					cmd->i_state, conn->cid);
3746 				spin_unlock_bh(&cmd->istate_lock);
3747 				goto transport_err;
3748 			}
3749 
3750 			if (sent_status) {
3751 				cmd->i_state = ISTATE_SENT_STATUS;
3752 				sent_status = 0;
3753 			}
3754 			spin_unlock_bh(&cmd->istate_lock);
3755 
3756 			if (atomic_read(&conn->check_immediate_queue))
3757 				goto get_immediate;
3758 
3759 			goto get_response;
3760 		} else
3761 			conn->tx_response_queue = 0;
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_list) {
3939 
3940 		list_del(&cmd->i_list);
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_list) {
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 		iscsit_close_session(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 	iscsit_close_session(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 	iscsit_close_session(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