1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18 
19 #include <linux/string.h>
20 #include <linux/kthread.h>
21 #include <linux/crypto.h>
22 #include <linux/completion.h>
23 #include <linux/module.h>
24 #include <linux/idr.h>
25 #include <asm/unaligned.h>
26 #include <scsi/scsi_device.h>
27 #include <scsi/iscsi_proto.h>
28 #include <scsi/scsi_tcq.h>
29 #include <target/target_core_base.h>
30 #include <target/target_core_fabric.h>
31 #include <target/target_core_configfs.h>
32 
33 #include "iscsi_target_core.h"
34 #include "iscsi_target_parameters.h"
35 #include "iscsi_target_seq_pdu_list.h"
36 #include "iscsi_target_tq.h"
37 #include "iscsi_target_configfs.h"
38 #include "iscsi_target_datain_values.h"
39 #include "iscsi_target_erl0.h"
40 #include "iscsi_target_erl1.h"
41 #include "iscsi_target_erl2.h"
42 #include "iscsi_target_login.h"
43 #include "iscsi_target_tmr.h"
44 #include "iscsi_target_tpg.h"
45 #include "iscsi_target_util.h"
46 #include "iscsi_target.h"
47 #include "iscsi_target_device.h"
48 #include "iscsi_target_stat.h"
49 
50 #include <target/iscsi/iscsi_transport.h>
51 
52 static LIST_HEAD(g_tiqn_list);
53 static LIST_HEAD(g_np_list);
54 static DEFINE_SPINLOCK(tiqn_lock);
55 static DEFINE_SPINLOCK(np_lock);
56 
57 static struct idr tiqn_idr;
58 struct idr sess_idr;
59 struct mutex auth_id_lock;
60 spinlock_t sess_idr_lock;
61 
62 struct iscsit_global *iscsit_global;
63 
64 struct kmem_cache *lio_qr_cache;
65 struct kmem_cache *lio_dr_cache;
66 struct kmem_cache *lio_ooo_cache;
67 struct kmem_cache *lio_r2t_cache;
68 
69 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
70 			struct iscsi_scsi_req *, u32);
71 
72 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
73 {
74 	struct iscsi_tiqn *tiqn = NULL;
75 
76 	spin_lock(&tiqn_lock);
77 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
78 		if (!strcmp(tiqn->tiqn, buf)) {
79 
80 			spin_lock(&tiqn->tiqn_state_lock);
81 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
82 				tiqn->tiqn_access_count++;
83 				spin_unlock(&tiqn->tiqn_state_lock);
84 				spin_unlock(&tiqn_lock);
85 				return tiqn;
86 			}
87 			spin_unlock(&tiqn->tiqn_state_lock);
88 		}
89 	}
90 	spin_unlock(&tiqn_lock);
91 
92 	return NULL;
93 }
94 
95 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
96 {
97 	spin_lock(&tiqn->tiqn_state_lock);
98 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
99 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
100 		spin_unlock(&tiqn->tiqn_state_lock);
101 		return 0;
102 	}
103 	spin_unlock(&tiqn->tiqn_state_lock);
104 
105 	return -1;
106 }
107 
108 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
109 {
110 	spin_lock(&tiqn->tiqn_state_lock);
111 	tiqn->tiqn_access_count--;
112 	spin_unlock(&tiqn->tiqn_state_lock);
113 }
114 
115 /*
116  * Note that IQN formatting is expected to be done in userspace, and
117  * no explict IQN format checks are done here.
118  */
119 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
120 {
121 	struct iscsi_tiqn *tiqn = NULL;
122 	int ret;
123 
124 	if (strlen(buf) >= ISCSI_IQN_LEN) {
125 		pr_err("Target IQN exceeds %d bytes\n",
126 				ISCSI_IQN_LEN);
127 		return ERR_PTR(-EINVAL);
128 	}
129 
130 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
131 	if (!tiqn) {
132 		pr_err("Unable to allocate struct iscsi_tiqn\n");
133 		return ERR_PTR(-ENOMEM);
134 	}
135 
136 	sprintf(tiqn->tiqn, "%s", buf);
137 	INIT_LIST_HEAD(&tiqn->tiqn_list);
138 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
139 	spin_lock_init(&tiqn->tiqn_state_lock);
140 	spin_lock_init(&tiqn->tiqn_tpg_lock);
141 	spin_lock_init(&tiqn->sess_err_stats.lock);
142 	spin_lock_init(&tiqn->login_stats.lock);
143 	spin_lock_init(&tiqn->logout_stats.lock);
144 
145 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
146 
147 	idr_preload(GFP_KERNEL);
148 	spin_lock(&tiqn_lock);
149 
150 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
151 	if (ret < 0) {
152 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
153 		spin_unlock(&tiqn_lock);
154 		idr_preload_end();
155 		kfree(tiqn);
156 		return ERR_PTR(ret);
157 	}
158 	tiqn->tiqn_index = ret;
159 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
160 
161 	spin_unlock(&tiqn_lock);
162 	idr_preload_end();
163 
164 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
165 
166 	return tiqn;
167 
168 }
169 
170 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
171 {
172 	/*
173 	 * Wait for accesses to said struct iscsi_tiqn to end.
174 	 */
175 	spin_lock(&tiqn->tiqn_state_lock);
176 	while (tiqn->tiqn_access_count != 0) {
177 		spin_unlock(&tiqn->tiqn_state_lock);
178 		msleep(10);
179 		spin_lock(&tiqn->tiqn_state_lock);
180 	}
181 	spin_unlock(&tiqn->tiqn_state_lock);
182 }
183 
184 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
185 {
186 	/*
187 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
188 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
189 	 * attempts to access this struct iscsi_tiqn will fail from both transport
190 	 * fabric and control code paths.
191 	 */
192 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
193 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
194 		return;
195 	}
196 
197 	iscsit_wait_for_tiqn(tiqn);
198 
199 	spin_lock(&tiqn_lock);
200 	list_del(&tiqn->tiqn_list);
201 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
202 	spin_unlock(&tiqn_lock);
203 
204 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
205 			tiqn->tiqn);
206 	kfree(tiqn);
207 }
208 
209 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
210 {
211 	int ret;
212 	/*
213 	 * Determine if the network portal is accepting storage traffic.
214 	 */
215 	spin_lock_bh(&np->np_thread_lock);
216 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
217 		spin_unlock_bh(&np->np_thread_lock);
218 		return -1;
219 	}
220 	spin_unlock_bh(&np->np_thread_lock);
221 	/*
222 	 * Determine if the portal group is accepting storage traffic.
223 	 */
224 	spin_lock_bh(&tpg->tpg_state_lock);
225 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
226 		spin_unlock_bh(&tpg->tpg_state_lock);
227 		return -1;
228 	}
229 	spin_unlock_bh(&tpg->tpg_state_lock);
230 
231 	/*
232 	 * Here we serialize access across the TIQN+TPG Tuple.
233 	 */
234 	ret = down_interruptible(&tpg->np_login_sem);
235 	if ((ret != 0) || signal_pending(current))
236 		return -1;
237 
238 	spin_lock_bh(&tpg->tpg_state_lock);
239 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
240 		spin_unlock_bh(&tpg->tpg_state_lock);
241 		up(&tpg->np_login_sem);
242 		return -1;
243 	}
244 	spin_unlock_bh(&tpg->tpg_state_lock);
245 
246 	return 0;
247 }
248 
249 void iscsit_login_kref_put(struct kref *kref)
250 {
251 	struct iscsi_tpg_np *tpg_np = container_of(kref,
252 				struct iscsi_tpg_np, tpg_np_kref);
253 
254 	complete(&tpg_np->tpg_np_comp);
255 }
256 
257 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
258 		       struct iscsi_tpg_np *tpg_np)
259 {
260 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
261 
262 	up(&tpg->np_login_sem);
263 
264 	if (tpg_np)
265 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
266 
267 	if (tiqn)
268 		iscsit_put_tiqn_for_login(tiqn);
269 
270 	return 0;
271 }
272 
273 bool iscsit_check_np_match(
274 	struct __kernel_sockaddr_storage *sockaddr,
275 	struct iscsi_np *np,
276 	int network_transport)
277 {
278 	struct sockaddr_in *sock_in, *sock_in_e;
279 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
280 	bool ip_match = false;
281 	u16 port;
282 
283 	if (sockaddr->ss_family == AF_INET6) {
284 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
285 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
286 
287 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
288 			    &sock_in6_e->sin6_addr.in6_u,
289 			    sizeof(struct in6_addr)))
290 			ip_match = true;
291 
292 		port = ntohs(sock_in6->sin6_port);
293 	} else {
294 		sock_in = (struct sockaddr_in *)sockaddr;
295 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
296 
297 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
298 			ip_match = true;
299 
300 		port = ntohs(sock_in->sin_port);
301 	}
302 
303 	if ((ip_match == true) && (np->np_port == port) &&
304 	    (np->np_network_transport == network_transport))
305 		return true;
306 
307 	return false;
308 }
309 
310 static struct iscsi_np *iscsit_get_np(
311 	struct __kernel_sockaddr_storage *sockaddr,
312 	int network_transport)
313 {
314 	struct iscsi_np *np;
315 	bool match;
316 
317 	spin_lock_bh(&np_lock);
318 	list_for_each_entry(np, &g_np_list, np_list) {
319 		spin_lock(&np->np_thread_lock);
320 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
321 			spin_unlock(&np->np_thread_lock);
322 			continue;
323 		}
324 
325 		match = iscsit_check_np_match(sockaddr, np, network_transport);
326 		if (match == true) {
327 			/*
328 			 * Increment the np_exports reference count now to
329 			 * prevent iscsit_del_np() below from being called
330 			 * while iscsi_tpg_add_network_portal() is called.
331 			 */
332 			np->np_exports++;
333 			spin_unlock(&np->np_thread_lock);
334 			spin_unlock_bh(&np_lock);
335 			return np;
336 		}
337 		spin_unlock(&np->np_thread_lock);
338 	}
339 	spin_unlock_bh(&np_lock);
340 
341 	return NULL;
342 }
343 
344 struct iscsi_np *iscsit_add_np(
345 	struct __kernel_sockaddr_storage *sockaddr,
346 	char *ip_str,
347 	int network_transport)
348 {
349 	struct sockaddr_in *sock_in;
350 	struct sockaddr_in6 *sock_in6;
351 	struct iscsi_np *np;
352 	int ret;
353 	/*
354 	 * Locate the existing struct iscsi_np if already active..
355 	 */
356 	np = iscsit_get_np(sockaddr, network_transport);
357 	if (np)
358 		return np;
359 
360 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
361 	if (!np) {
362 		pr_err("Unable to allocate memory for struct iscsi_np\n");
363 		return ERR_PTR(-ENOMEM);
364 	}
365 
366 	np->np_flags |= NPF_IP_NETWORK;
367 	if (sockaddr->ss_family == AF_INET6) {
368 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
369 		snprintf(np->np_ip, IPV6_ADDRESS_SPACE, "%s", ip_str);
370 		np->np_port = ntohs(sock_in6->sin6_port);
371 	} else {
372 		sock_in = (struct sockaddr_in *)sockaddr;
373 		sprintf(np->np_ip, "%s", ip_str);
374 		np->np_port = ntohs(sock_in->sin_port);
375 	}
376 
377 	np->np_network_transport = network_transport;
378 	spin_lock_init(&np->np_thread_lock);
379 	init_completion(&np->np_restart_comp);
380 	INIT_LIST_HEAD(&np->np_list);
381 
382 	ret = iscsi_target_setup_login_socket(np, sockaddr);
383 	if (ret != 0) {
384 		kfree(np);
385 		return ERR_PTR(ret);
386 	}
387 
388 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
389 	if (IS_ERR(np->np_thread)) {
390 		pr_err("Unable to create kthread: iscsi_np\n");
391 		ret = PTR_ERR(np->np_thread);
392 		kfree(np);
393 		return ERR_PTR(ret);
394 	}
395 	/*
396 	 * Increment the np_exports reference count now to prevent
397 	 * iscsit_del_np() below from being run while a new call to
398 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
399 	 * active.  We don't need to hold np->np_thread_lock at this
400 	 * point because iscsi_np has not been added to g_np_list yet.
401 	 */
402 	np->np_exports = 1;
403 
404 	spin_lock_bh(&np_lock);
405 	list_add_tail(&np->np_list, &g_np_list);
406 	spin_unlock_bh(&np_lock);
407 
408 	pr_debug("CORE[0] - Added Network Portal: %s:%hu on %s\n",
409 		np->np_ip, np->np_port, np->np_transport->name);
410 
411 	return np;
412 }
413 
414 int iscsit_reset_np_thread(
415 	struct iscsi_np *np,
416 	struct iscsi_tpg_np *tpg_np,
417 	struct iscsi_portal_group *tpg,
418 	bool shutdown)
419 {
420 	spin_lock_bh(&np->np_thread_lock);
421 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
422 		spin_unlock_bh(&np->np_thread_lock);
423 		return 0;
424 	}
425 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
426 
427 	if (np->np_thread) {
428 		spin_unlock_bh(&np->np_thread_lock);
429 		send_sig(SIGINT, np->np_thread, 1);
430 		wait_for_completion(&np->np_restart_comp);
431 		spin_lock_bh(&np->np_thread_lock);
432 	}
433 	spin_unlock_bh(&np->np_thread_lock);
434 
435 	if (tpg_np && shutdown) {
436 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
437 
438 		wait_for_completion(&tpg_np->tpg_np_comp);
439 	}
440 
441 	return 0;
442 }
443 
444 static void iscsit_free_np(struct iscsi_np *np)
445 {
446 	if (np->np_socket)
447 		sock_release(np->np_socket);
448 }
449 
450 int iscsit_del_np(struct iscsi_np *np)
451 {
452 	spin_lock_bh(&np->np_thread_lock);
453 	np->np_exports--;
454 	if (np->np_exports) {
455 		spin_unlock_bh(&np->np_thread_lock);
456 		return 0;
457 	}
458 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
459 	spin_unlock_bh(&np->np_thread_lock);
460 
461 	if (np->np_thread) {
462 		/*
463 		 * We need to send the signal to wakeup Linux/Net
464 		 * which may be sleeping in sock_accept()..
465 		 */
466 		send_sig(SIGINT, np->np_thread, 1);
467 		kthread_stop(np->np_thread);
468 		np->np_thread = NULL;
469 	}
470 
471 	np->np_transport->iscsit_free_np(np);
472 
473 	spin_lock_bh(&np_lock);
474 	list_del(&np->np_list);
475 	spin_unlock_bh(&np_lock);
476 
477 	pr_debug("CORE[0] - Removed Network Portal: %s:%hu on %s\n",
478 		np->np_ip, np->np_port, np->np_transport->name);
479 
480 	iscsit_put_transport(np->np_transport);
481 	kfree(np);
482 	return 0;
483 }
484 
485 static int iscsit_immediate_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
486 static int iscsit_response_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
487 
488 static int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
489 {
490 	iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
491 	return 0;
492 }
493 
494 static struct iscsit_transport iscsi_target_transport = {
495 	.name			= "iSCSI/TCP",
496 	.transport_type		= ISCSI_TCP,
497 	.owner			= NULL,
498 	.iscsit_setup_np	= iscsit_setup_np,
499 	.iscsit_accept_np	= iscsit_accept_np,
500 	.iscsit_free_np		= iscsit_free_np,
501 	.iscsit_get_login_rx	= iscsit_get_login_rx,
502 	.iscsit_put_login_tx	= iscsit_put_login_tx,
503 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
504 	.iscsit_immediate_queue	= iscsit_immediate_queue,
505 	.iscsit_response_queue	= iscsit_response_queue,
506 	.iscsit_queue_data_in	= iscsit_queue_rsp,
507 	.iscsit_queue_status	= iscsit_queue_rsp,
508 };
509 
510 static int __init iscsi_target_init_module(void)
511 {
512 	int ret = 0;
513 
514 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
515 
516 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
517 	if (!iscsit_global) {
518 		pr_err("Unable to allocate memory for iscsit_global\n");
519 		return -1;
520 	}
521 	mutex_init(&auth_id_lock);
522 	spin_lock_init(&sess_idr_lock);
523 	idr_init(&tiqn_idr);
524 	idr_init(&sess_idr);
525 
526 	ret = iscsi_target_register_configfs();
527 	if (ret < 0)
528 		goto out;
529 
530 	ret = iscsi_thread_set_init();
531 	if (ret < 0)
532 		goto configfs_out;
533 
534 	if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
535 			TARGET_THREAD_SET_COUNT) {
536 		pr_err("iscsi_allocate_thread_sets() returned"
537 			" unexpected value!\n");
538 		goto ts_out1;
539 	}
540 
541 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
542 			sizeof(struct iscsi_queue_req),
543 			__alignof__(struct iscsi_queue_req), 0, NULL);
544 	if (!lio_qr_cache) {
545 		pr_err("nable to kmem_cache_create() for"
546 				" lio_qr_cache\n");
547 		goto ts_out2;
548 	}
549 
550 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
551 			sizeof(struct iscsi_datain_req),
552 			__alignof__(struct iscsi_datain_req), 0, NULL);
553 	if (!lio_dr_cache) {
554 		pr_err("Unable to kmem_cache_create() for"
555 				" lio_dr_cache\n");
556 		goto qr_out;
557 	}
558 
559 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
560 			sizeof(struct iscsi_ooo_cmdsn),
561 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
562 	if (!lio_ooo_cache) {
563 		pr_err("Unable to kmem_cache_create() for"
564 				" lio_ooo_cache\n");
565 		goto dr_out;
566 	}
567 
568 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
569 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
570 			0, NULL);
571 	if (!lio_r2t_cache) {
572 		pr_err("Unable to kmem_cache_create() for"
573 				" lio_r2t_cache\n");
574 		goto ooo_out;
575 	}
576 
577 	iscsit_register_transport(&iscsi_target_transport);
578 
579 	if (iscsit_load_discovery_tpg() < 0)
580 		goto r2t_out;
581 
582 	return ret;
583 r2t_out:
584 	kmem_cache_destroy(lio_r2t_cache);
585 ooo_out:
586 	kmem_cache_destroy(lio_ooo_cache);
587 dr_out:
588 	kmem_cache_destroy(lio_dr_cache);
589 qr_out:
590 	kmem_cache_destroy(lio_qr_cache);
591 ts_out2:
592 	iscsi_deallocate_thread_sets();
593 ts_out1:
594 	iscsi_thread_set_free();
595 configfs_out:
596 	iscsi_target_deregister_configfs();
597 out:
598 	kfree(iscsit_global);
599 	return -ENOMEM;
600 }
601 
602 static void __exit iscsi_target_cleanup_module(void)
603 {
604 	iscsi_deallocate_thread_sets();
605 	iscsi_thread_set_free();
606 	iscsit_release_discovery_tpg();
607 	iscsit_unregister_transport(&iscsi_target_transport);
608 	kmem_cache_destroy(lio_qr_cache);
609 	kmem_cache_destroy(lio_dr_cache);
610 	kmem_cache_destroy(lio_ooo_cache);
611 	kmem_cache_destroy(lio_r2t_cache);
612 
613 	iscsi_target_deregister_configfs();
614 
615 	kfree(iscsit_global);
616 }
617 
618 static int iscsit_add_reject(
619 	struct iscsi_conn *conn,
620 	u8 reason,
621 	unsigned char *buf)
622 {
623 	struct iscsi_cmd *cmd;
624 
625 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
626 	if (!cmd)
627 		return -1;
628 
629 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
630 	cmd->reject_reason = reason;
631 
632 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
633 	if (!cmd->buf_ptr) {
634 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
635 		iscsit_free_cmd(cmd, false);
636 		return -1;
637 	}
638 
639 	spin_lock_bh(&conn->cmd_lock);
640 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
641 	spin_unlock_bh(&conn->cmd_lock);
642 
643 	cmd->i_state = ISTATE_SEND_REJECT;
644 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
645 
646 	return -1;
647 }
648 
649 static int iscsit_add_reject_from_cmd(
650 	struct iscsi_cmd *cmd,
651 	u8 reason,
652 	bool add_to_conn,
653 	unsigned char *buf)
654 {
655 	struct iscsi_conn *conn;
656 
657 	if (!cmd->conn) {
658 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
659 				cmd->init_task_tag);
660 		return -1;
661 	}
662 	conn = cmd->conn;
663 
664 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
665 	cmd->reject_reason = reason;
666 
667 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
668 	if (!cmd->buf_ptr) {
669 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
670 		iscsit_free_cmd(cmd, false);
671 		return -1;
672 	}
673 
674 	if (add_to_conn) {
675 		spin_lock_bh(&conn->cmd_lock);
676 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
677 		spin_unlock_bh(&conn->cmd_lock);
678 	}
679 
680 	cmd->i_state = ISTATE_SEND_REJECT;
681 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
682 	/*
683 	 * Perform the kref_put now if se_cmd has already been setup by
684 	 * scsit_setup_scsi_cmd()
685 	 */
686 	if (cmd->se_cmd.se_tfo != NULL) {
687 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
688 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
689 	}
690 	return -1;
691 }
692 
693 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
694 				 unsigned char *buf)
695 {
696 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
697 }
698 
699 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
700 {
701 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
702 }
703 
704 /*
705  * Map some portion of the allocated scatterlist to an iovec, suitable for
706  * kernel sockets to copy data in/out.
707  */
708 static int iscsit_map_iovec(
709 	struct iscsi_cmd *cmd,
710 	struct kvec *iov,
711 	u32 data_offset,
712 	u32 data_length)
713 {
714 	u32 i = 0;
715 	struct scatterlist *sg;
716 	unsigned int page_off;
717 
718 	/*
719 	 * We know each entry in t_data_sg contains a page.
720 	 */
721 	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
722 	page_off = (data_offset % PAGE_SIZE);
723 
724 	cmd->first_data_sg = sg;
725 	cmd->first_data_sg_off = page_off;
726 
727 	while (data_length) {
728 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
729 
730 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
731 		iov[i].iov_len = cur_len;
732 
733 		data_length -= cur_len;
734 		page_off = 0;
735 		sg = sg_next(sg);
736 		i++;
737 	}
738 
739 	cmd->kmapped_nents = i;
740 
741 	return i;
742 }
743 
744 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
745 {
746 	u32 i;
747 	struct scatterlist *sg;
748 
749 	sg = cmd->first_data_sg;
750 
751 	for (i = 0; i < cmd->kmapped_nents; i++)
752 		kunmap(sg_page(&sg[i]));
753 }
754 
755 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
756 {
757 	LIST_HEAD(ack_list);
758 	struct iscsi_cmd *cmd, *cmd_p;
759 
760 	conn->exp_statsn = exp_statsn;
761 
762 	if (conn->sess->sess_ops->RDMAExtensions)
763 		return;
764 
765 	spin_lock_bh(&conn->cmd_lock);
766 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
767 		spin_lock(&cmd->istate_lock);
768 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
769 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
770 			cmd->i_state = ISTATE_REMOVE;
771 			spin_unlock(&cmd->istate_lock);
772 			list_move_tail(&cmd->i_conn_node, &ack_list);
773 			continue;
774 		}
775 		spin_unlock(&cmd->istate_lock);
776 	}
777 	spin_unlock_bh(&conn->cmd_lock);
778 
779 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
780 		list_del(&cmd->i_conn_node);
781 		iscsit_free_cmd(cmd, false);
782 	}
783 }
784 
785 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
786 {
787 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
788 
789 	iov_count += ISCSI_IOV_DATA_BUFFER;
790 
791 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
792 	if (!cmd->iov_data) {
793 		pr_err("Unable to allocate cmd->iov_data\n");
794 		return -ENOMEM;
795 	}
796 
797 	cmd->orig_iov_data_count = iov_count;
798 	return 0;
799 }
800 
801 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
802 			  unsigned char *buf)
803 {
804 	int data_direction, payload_length;
805 	struct iscsi_scsi_req *hdr;
806 	int iscsi_task_attr;
807 	int sam_task_attr;
808 
809 	atomic_long_inc(&conn->sess->cmd_pdus);
810 
811 	hdr			= (struct iscsi_scsi_req *) buf;
812 	payload_length		= ntoh24(hdr->dlength);
813 
814 	/* FIXME; Add checks for AdditionalHeaderSegment */
815 
816 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
817 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
818 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
819 				" not set. Bad iSCSI Initiator.\n");
820 		return iscsit_add_reject_cmd(cmd,
821 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
822 	}
823 
824 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
825 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
826 		/*
827 		 * From RFC-3720 Section 10.3.1:
828 		 *
829 		 * "Either or both of R and W MAY be 1 when either the
830 		 *  Expected Data Transfer Length and/or Bidirectional Read
831 		 *  Expected Data Transfer Length are 0"
832 		 *
833 		 * For this case, go ahead and clear the unnecssary bits
834 		 * to avoid any confusion with ->data_direction.
835 		 */
836 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
837 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
838 
839 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
840 			" set when Expected Data Transfer Length is 0 for"
841 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
842 	}
843 
844 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
845 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
846 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
847 			" MUST be set if Expected Data Transfer Length is not 0."
848 			" Bad iSCSI Initiator\n");
849 		return iscsit_add_reject_cmd(cmd,
850 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
851 	}
852 
853 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
854 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
855 		pr_err("Bidirectional operations not supported!\n");
856 		return iscsit_add_reject_cmd(cmd,
857 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
858 	}
859 
860 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
861 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
862 				" Scsi Command PDU.\n");
863 		return iscsit_add_reject_cmd(cmd,
864 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
865 	}
866 
867 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
868 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
869 			" protocol error.\n", payload_length);
870 		return iscsit_add_reject_cmd(cmd,
871 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
872 	}
873 
874 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
875 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
876 		pr_err("Expected Data Transfer Length and Length of"
877 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
878 			" bit is not set protocol error\n");
879 		return iscsit_add_reject_cmd(cmd,
880 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
881 	}
882 
883 	if (payload_length > be32_to_cpu(hdr->data_length)) {
884 		pr_err("DataSegmentLength: %u is greater than"
885 			" EDTL: %u, protocol error.\n", payload_length,
886 				hdr->data_length);
887 		return iscsit_add_reject_cmd(cmd,
888 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
889 	}
890 
891 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
892 		pr_err("DataSegmentLength: %u is greater than"
893 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
894 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
895 		return iscsit_add_reject_cmd(cmd,
896 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
897 	}
898 
899 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
900 		pr_err("DataSegmentLength: %u is greater than"
901 			" FirstBurstLength: %u, protocol error.\n",
902 			payload_length, conn->sess->sess_ops->FirstBurstLength);
903 		return iscsit_add_reject_cmd(cmd,
904 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
905 	}
906 
907 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
908 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
909 			  DMA_NONE;
910 
911 	cmd->data_direction = data_direction;
912 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
913 	/*
914 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
915 	 */
916 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
917 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
918 		sam_task_attr = MSG_SIMPLE_TAG;
919 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
920 		sam_task_attr = MSG_ORDERED_TAG;
921 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
922 		sam_task_attr = MSG_HEAD_TAG;
923 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
924 		sam_task_attr = MSG_ACA_TAG;
925 	else {
926 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
927 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
928 		sam_task_attr = MSG_SIMPLE_TAG;
929 	}
930 
931 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
932 	cmd->i_state		= ISTATE_NEW_CMD;
933 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
934 	cmd->immediate_data	= (payload_length) ? 1 : 0;
935 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
936 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
937 	if (cmd->unsolicited_data)
938 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
939 
940 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
941 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
942 		spin_lock_bh(&conn->sess->ttt_lock);
943 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
944 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
945 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
946 		spin_unlock_bh(&conn->sess->ttt_lock);
947 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
948 		cmd->targ_xfer_tag = 0xFFFFFFFF;
949 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
950 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
951 	cmd->first_burst_len	= payload_length;
952 
953 	if (!conn->sess->sess_ops->RDMAExtensions &&
954 	     cmd->data_direction == DMA_FROM_DEVICE) {
955 		struct iscsi_datain_req *dr;
956 
957 		dr = iscsit_allocate_datain_req();
958 		if (!dr)
959 			return iscsit_add_reject_cmd(cmd,
960 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
961 
962 		iscsit_attach_datain_req(cmd, dr);
963 	}
964 
965 	/*
966 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
967 	 */
968 	transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
969 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
970 			cmd->data_direction, sam_task_attr,
971 			cmd->sense_buffer + 2);
972 
973 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
974 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
975 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
976 		conn->cid);
977 
978 	target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
979 
980 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
981 						     scsilun_to_int(&hdr->lun));
982 	if (cmd->sense_reason)
983 		goto attach_cmd;
984 
985 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
986 	if (cmd->sense_reason) {
987 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
988 			return iscsit_add_reject_cmd(cmd,
989 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
990 		}
991 
992 		goto attach_cmd;
993 	}
994 
995 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
996 		return iscsit_add_reject_cmd(cmd,
997 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
998 	}
999 
1000 attach_cmd:
1001 	spin_lock_bh(&conn->cmd_lock);
1002 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1003 	spin_unlock_bh(&conn->cmd_lock);
1004 	/*
1005 	 * Check if we need to delay processing because of ALUA
1006 	 * Active/NonOptimized primary access state..
1007 	 */
1008 	core_alua_check_nonop_delay(&cmd->se_cmd);
1009 
1010 	return 0;
1011 }
1012 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1013 
1014 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1015 {
1016 	iscsit_set_dataout_sequence_values(cmd);
1017 
1018 	spin_lock_bh(&cmd->dataout_timeout_lock);
1019 	iscsit_start_dataout_timer(cmd, cmd->conn);
1020 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1021 }
1022 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1023 
1024 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1025 			    struct iscsi_scsi_req *hdr)
1026 {
1027 	int cmdsn_ret = 0;
1028 	/*
1029 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1030 	 * the Immediate Bit is not set, and no Immediate
1031 	 * Data is attached.
1032 	 *
1033 	 * A PDU/CmdSN carrying Immediate Data can only
1034 	 * be processed after the DataCRC has passed.
1035 	 * If the DataCRC fails, the CmdSN MUST NOT
1036 	 * be acknowledged. (See below)
1037 	 */
1038 	if (!cmd->immediate_data) {
1039 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1040 					(unsigned char *)hdr, hdr->cmdsn);
1041 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1042 			return -1;
1043 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1044 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1045 			return 0;
1046 		}
1047 	}
1048 
1049 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1050 
1051 	/*
1052 	 * If no Immediate Data is attached, it's OK to return now.
1053 	 */
1054 	if (!cmd->immediate_data) {
1055 		if (!cmd->sense_reason && cmd->unsolicited_data)
1056 			iscsit_set_unsoliticed_dataout(cmd);
1057 		if (!cmd->sense_reason)
1058 			return 0;
1059 
1060 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1061 		return 0;
1062 	}
1063 
1064 	/*
1065 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1066 	 * execution.  These exceptions are processed in CmdSN order using
1067 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1068 	 */
1069 	if (cmd->sense_reason) {
1070 		if (cmd->reject_reason)
1071 			return 0;
1072 
1073 		return 1;
1074 	}
1075 	/*
1076 	 * Call directly into transport_generic_new_cmd() to perform
1077 	 * the backend memory allocation.
1078 	 */
1079 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1080 	if (cmd->sense_reason)
1081 		return 1;
1082 
1083 	return 0;
1084 }
1085 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1086 
1087 static int
1088 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1089 			  bool dump_payload)
1090 {
1091 	struct iscsi_conn *conn = cmd->conn;
1092 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1093 	/*
1094 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1095 	 */
1096 	if (dump_payload == true)
1097 		goto after_immediate_data;
1098 
1099 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1100 					cmd->first_burst_len);
1101 after_immediate_data:
1102 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1103 		/*
1104 		 * A PDU/CmdSN carrying Immediate Data passed
1105 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1106 		 * Immediate Bit is not set.
1107 		 */
1108 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1109 					(unsigned char *)hdr, hdr->cmdsn);
1110 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1111 			return -1;
1112 
1113 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1114 			int rc;
1115 
1116 			rc = iscsit_dump_data_payload(cmd->conn,
1117 						      cmd->first_burst_len, 1);
1118 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1119 			return rc;
1120 		} else if (cmd->unsolicited_data)
1121 			iscsit_set_unsoliticed_dataout(cmd);
1122 
1123 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1124 		/*
1125 		 * Immediate Data failed DataCRC and ERL>=1,
1126 		 * silently drop this PDU and let the initiator
1127 		 * plug the CmdSN gap.
1128 		 *
1129 		 * FIXME: Send Unsolicited NOPIN with reserved
1130 		 * TTT here to help the initiator figure out
1131 		 * the missing CmdSN, although they should be
1132 		 * intelligent enough to determine the missing
1133 		 * CmdSN and issue a retry to plug the sequence.
1134 		 */
1135 		cmd->i_state = ISTATE_REMOVE;
1136 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1137 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1138 		return -1;
1139 
1140 	return 0;
1141 }
1142 
1143 static int
1144 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1145 			   unsigned char *buf)
1146 {
1147 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1148 	int rc, immed_data;
1149 	bool dump_payload = false;
1150 
1151 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1152 	if (rc < 0)
1153 		return 0;
1154 	/*
1155 	 * Allocation iovecs needed for struct socket operations for
1156 	 * traditional iSCSI block I/O.
1157 	 */
1158 	if (iscsit_allocate_iovecs(cmd) < 0) {
1159 		return iscsit_add_reject_cmd(cmd,
1160 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1161 	}
1162 	immed_data = cmd->immediate_data;
1163 
1164 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1165 	if (rc < 0)
1166 		return rc;
1167 	else if (rc > 0)
1168 		dump_payload = true;
1169 
1170 	if (!immed_data)
1171 		return 0;
1172 
1173 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1174 }
1175 
1176 static u32 iscsit_do_crypto_hash_sg(
1177 	struct hash_desc *hash,
1178 	struct iscsi_cmd *cmd,
1179 	u32 data_offset,
1180 	u32 data_length,
1181 	u32 padding,
1182 	u8 *pad_bytes)
1183 {
1184 	u32 data_crc;
1185 	u32 i;
1186 	struct scatterlist *sg;
1187 	unsigned int page_off;
1188 
1189 	crypto_hash_init(hash);
1190 
1191 	sg = cmd->first_data_sg;
1192 	page_off = cmd->first_data_sg_off;
1193 
1194 	i = 0;
1195 	while (data_length) {
1196 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1197 
1198 		crypto_hash_update(hash, &sg[i], cur_len);
1199 
1200 		data_length -= cur_len;
1201 		page_off = 0;
1202 		i++;
1203 	}
1204 
1205 	if (padding) {
1206 		struct scatterlist pad_sg;
1207 
1208 		sg_init_one(&pad_sg, pad_bytes, padding);
1209 		crypto_hash_update(hash, &pad_sg, padding);
1210 	}
1211 	crypto_hash_final(hash, (u8 *) &data_crc);
1212 
1213 	return data_crc;
1214 }
1215 
1216 static void iscsit_do_crypto_hash_buf(
1217 	struct hash_desc *hash,
1218 	const void *buf,
1219 	u32 payload_length,
1220 	u32 padding,
1221 	u8 *pad_bytes,
1222 	u8 *data_crc)
1223 {
1224 	struct scatterlist sg;
1225 
1226 	crypto_hash_init(hash);
1227 
1228 	sg_init_one(&sg, buf, payload_length);
1229 	crypto_hash_update(hash, &sg, payload_length);
1230 
1231 	if (padding) {
1232 		sg_init_one(&sg, pad_bytes, padding);
1233 		crypto_hash_update(hash, &sg, padding);
1234 	}
1235 	crypto_hash_final(hash, data_crc);
1236 }
1237 
1238 int
1239 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1240 			  struct iscsi_cmd **out_cmd)
1241 {
1242 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1243 	struct iscsi_cmd *cmd = NULL;
1244 	struct se_cmd *se_cmd;
1245 	u32 payload_length = ntoh24(hdr->dlength);
1246 	int rc;
1247 
1248 	if (!payload_length) {
1249 		pr_warn("DataOUT payload is ZERO, ignoring.\n");
1250 		return 0;
1251 	}
1252 
1253 	/* iSCSI write */
1254 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1255 
1256 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1257 		pr_err("DataSegmentLength: %u is greater than"
1258 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1259 			conn->conn_ops->MaxXmitDataSegmentLength);
1260 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1261 					 buf);
1262 	}
1263 
1264 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1265 			payload_length);
1266 	if (!cmd)
1267 		return 0;
1268 
1269 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1270 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1271 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1272 		payload_length, conn->cid);
1273 
1274 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1275 		pr_err("Command ITT: 0x%08x received DataOUT after"
1276 			" last DataOUT received, dumping payload\n",
1277 			cmd->init_task_tag);
1278 		return iscsit_dump_data_payload(conn, payload_length, 1);
1279 	}
1280 
1281 	if (cmd->data_direction != DMA_TO_DEVICE) {
1282 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1283 			" NON-WRITE command.\n", cmd->init_task_tag);
1284 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
1285 	}
1286 	se_cmd = &cmd->se_cmd;
1287 	iscsit_mod_dataout_timer(cmd);
1288 
1289 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1290 		pr_err("DataOut Offset: %u, Length %u greater than"
1291 			" iSCSI Command EDTL %u, protocol error.\n",
1292 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1293 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1294 	}
1295 
1296 	if (cmd->unsolicited_data) {
1297 		int dump_unsolicited_data = 0;
1298 
1299 		if (conn->sess->sess_ops->InitialR2T) {
1300 			pr_err("Received unexpected unsolicited data"
1301 				" while InitialR2T=Yes, protocol error.\n");
1302 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1303 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1304 			return -1;
1305 		}
1306 		/*
1307 		 * Special case for dealing with Unsolicited DataOUT
1308 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1309 		 * failures;
1310 		 */
1311 
1312 		/* Something's amiss if we're not in WRITE_PENDING state... */
1313 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1314 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1315 			dump_unsolicited_data = 1;
1316 
1317 		if (dump_unsolicited_data) {
1318 			/*
1319 			 * Check if a delayed TASK_ABORTED status needs to
1320 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1321 			 * received with the unsolicitied data out.
1322 			 */
1323 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1324 				iscsit_stop_dataout_timer(cmd);
1325 
1326 			transport_check_aborted_status(se_cmd,
1327 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1328 			return iscsit_dump_data_payload(conn, payload_length, 1);
1329 		}
1330 	} else {
1331 		/*
1332 		 * For the normal solicited data path:
1333 		 *
1334 		 * Check for a delayed TASK_ABORTED status and dump any
1335 		 * incoming data out payload if one exists.  Also, when the
1336 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1337 		 * data out sequence, we decrement outstanding_r2ts.  Once
1338 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1339 		 * TASK_ABORTED status.
1340 		 */
1341 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1342 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1343 				if (--cmd->outstanding_r2ts < 1) {
1344 					iscsit_stop_dataout_timer(cmd);
1345 					transport_check_aborted_status(
1346 							se_cmd, 1);
1347 				}
1348 
1349 			return iscsit_dump_data_payload(conn, payload_length, 1);
1350 		}
1351 	}
1352 	/*
1353 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1354 	 * within-command recovery checks before receiving the payload.
1355 	 */
1356 	rc = iscsit_check_pre_dataout(cmd, buf);
1357 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1358 		return 0;
1359 	else if (rc == DATAOUT_CANNOT_RECOVER)
1360 		return -1;
1361 
1362 	*out_cmd = cmd;
1363 	return 0;
1364 }
1365 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1366 
1367 static int
1368 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1369 		   struct iscsi_data *hdr)
1370 {
1371 	struct kvec *iov;
1372 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1373 	u32 payload_length = ntoh24(hdr->dlength);
1374 	int iov_ret, data_crc_failed = 0;
1375 
1376 	rx_size += payload_length;
1377 	iov = &cmd->iov_data[0];
1378 
1379 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1380 				   payload_length);
1381 	if (iov_ret < 0)
1382 		return -1;
1383 
1384 	iov_count += iov_ret;
1385 
1386 	padding = ((-payload_length) & 3);
1387 	if (padding != 0) {
1388 		iov[iov_count].iov_base	= cmd->pad_bytes;
1389 		iov[iov_count++].iov_len = padding;
1390 		rx_size += padding;
1391 		pr_debug("Receiving %u padding bytes.\n", padding);
1392 	}
1393 
1394 	if (conn->conn_ops->DataDigest) {
1395 		iov[iov_count].iov_base = &checksum;
1396 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1397 		rx_size += ISCSI_CRC_LEN;
1398 	}
1399 
1400 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1401 
1402 	iscsit_unmap_iovec(cmd);
1403 
1404 	if (rx_got != rx_size)
1405 		return -1;
1406 
1407 	if (conn->conn_ops->DataDigest) {
1408 		u32 data_crc;
1409 
1410 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1411 						    be32_to_cpu(hdr->offset),
1412 						    payload_length, padding,
1413 						    cmd->pad_bytes);
1414 
1415 		if (checksum != data_crc) {
1416 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1417 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1418 				" does not match computed 0x%08x\n",
1419 				hdr->itt, hdr->offset, payload_length,
1420 				hdr->datasn, checksum, data_crc);
1421 			data_crc_failed = 1;
1422 		} else {
1423 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1424 				" %u bytes of Data Out\n", checksum,
1425 				payload_length);
1426 		}
1427 	}
1428 
1429 	return data_crc_failed;
1430 }
1431 
1432 int
1433 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1434 			     bool data_crc_failed)
1435 {
1436 	struct iscsi_conn *conn = cmd->conn;
1437 	int rc, ooo_cmdsn;
1438 	/*
1439 	 * Increment post receive data and CRC values or perform
1440 	 * within-command recovery.
1441 	 */
1442 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1443 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1444 		return 0;
1445 	else if (rc == DATAOUT_SEND_R2T) {
1446 		iscsit_set_dataout_sequence_values(cmd);
1447 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1448 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1449 		/*
1450 		 * Handle extra special case for out of order
1451 		 * Unsolicited Data Out.
1452 		 */
1453 		spin_lock_bh(&cmd->istate_lock);
1454 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1455 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1456 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1457 		spin_unlock_bh(&cmd->istate_lock);
1458 
1459 		iscsit_stop_dataout_timer(cmd);
1460 		if (ooo_cmdsn)
1461 			return 0;
1462 		target_execute_cmd(&cmd->se_cmd);
1463 		return 0;
1464 	} else /* DATAOUT_CANNOT_RECOVER */
1465 		return -1;
1466 
1467 	return 0;
1468 }
1469 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1470 
1471 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1472 {
1473 	struct iscsi_cmd *cmd = NULL;
1474 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1475 	int rc;
1476 	bool data_crc_failed = false;
1477 
1478 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1479 	if (rc < 0)
1480 		return 0;
1481 	else if (!cmd)
1482 		return 0;
1483 
1484 	rc = iscsit_get_dataout(conn, cmd, hdr);
1485 	if (rc < 0)
1486 		return rc;
1487 	else if (rc > 0)
1488 		data_crc_failed = true;
1489 
1490 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1491 }
1492 
1493 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1494 			 struct iscsi_nopout *hdr)
1495 {
1496 	u32 payload_length = ntoh24(hdr->dlength);
1497 
1498 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1499 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1500 			" not set, protocol error.\n");
1501 		if (!cmd)
1502 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1503 						 (unsigned char *)hdr);
1504 
1505 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1506 					 (unsigned char *)hdr);
1507 	}
1508 
1509 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1510 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1511 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1512 			" error.\n", payload_length,
1513 			conn->conn_ops->MaxXmitDataSegmentLength);
1514 		if (!cmd)
1515 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1516 						 (unsigned char *)hdr);
1517 
1518 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1519 					 (unsigned char *)hdr);
1520 	}
1521 
1522 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1523 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1524 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1525 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1526 		payload_length);
1527 	/*
1528 	 * This is not a response to a Unsolicited NopIN, which means
1529 	 * it can either be a NOPOUT ping request (with a valid ITT),
1530 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1531 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1532 	 * can contain ping data.
1533 	 */
1534 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1535 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1536 		cmd->i_state		= ISTATE_SEND_NOPIN;
1537 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1538 						1 : 0);
1539 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1540 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1541 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1542 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1543 		cmd->data_direction	= DMA_NONE;
1544 	}
1545 
1546 	return 0;
1547 }
1548 EXPORT_SYMBOL(iscsit_setup_nop_out);
1549 
1550 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1551 			   struct iscsi_nopout *hdr)
1552 {
1553 	struct iscsi_cmd *cmd_p = NULL;
1554 	int cmdsn_ret = 0;
1555 	/*
1556 	 * Initiator is expecting a NopIN ping reply..
1557 	 */
1558 	if (hdr->itt != RESERVED_ITT) {
1559 		BUG_ON(!cmd);
1560 
1561 		spin_lock_bh(&conn->cmd_lock);
1562 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1563 		spin_unlock_bh(&conn->cmd_lock);
1564 
1565 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1566 
1567 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1568 			iscsit_add_cmd_to_response_queue(cmd, conn,
1569 							 cmd->i_state);
1570 			return 0;
1571 		}
1572 
1573 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1574 				(unsigned char *)hdr, hdr->cmdsn);
1575                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1576 			return 0;
1577 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1578 			return -1;
1579 
1580 		return 0;
1581 	}
1582 	/*
1583 	 * This was a response to a unsolicited NOPIN ping.
1584 	 */
1585 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1586 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1587 		if (!cmd_p)
1588 			return -EINVAL;
1589 
1590 		iscsit_stop_nopin_response_timer(conn);
1591 
1592 		cmd_p->i_state = ISTATE_REMOVE;
1593 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1594 
1595 		iscsit_start_nopin_timer(conn);
1596 		return 0;
1597 	}
1598 	/*
1599 	 * Otherwise, initiator is not expecting a NOPIN is response.
1600 	 * Just ignore for now.
1601 	 */
1602         return 0;
1603 }
1604 EXPORT_SYMBOL(iscsit_process_nop_out);
1605 
1606 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1607 				 unsigned char *buf)
1608 {
1609 	unsigned char *ping_data = NULL;
1610 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1611 	struct kvec *iov = NULL;
1612 	u32 payload_length = ntoh24(hdr->dlength);
1613 	int ret;
1614 
1615 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1616 	if (ret < 0)
1617 		return 0;
1618 	/*
1619 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1620 	 */
1621 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1622 		u32 checksum, data_crc, padding = 0;
1623 		int niov = 0, rx_got, rx_size = payload_length;
1624 
1625 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1626 		if (!ping_data) {
1627 			pr_err("Unable to allocate memory for"
1628 				" NOPOUT ping data.\n");
1629 			ret = -1;
1630 			goto out;
1631 		}
1632 
1633 		iov = &cmd->iov_misc[0];
1634 		iov[niov].iov_base	= ping_data;
1635 		iov[niov++].iov_len	= payload_length;
1636 
1637 		padding = ((-payload_length) & 3);
1638 		if (padding != 0) {
1639 			pr_debug("Receiving %u additional bytes"
1640 				" for padding.\n", padding);
1641 			iov[niov].iov_base	= &cmd->pad_bytes;
1642 			iov[niov++].iov_len	= padding;
1643 			rx_size += padding;
1644 		}
1645 		if (conn->conn_ops->DataDigest) {
1646 			iov[niov].iov_base	= &checksum;
1647 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1648 			rx_size += ISCSI_CRC_LEN;
1649 		}
1650 
1651 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1652 		if (rx_got != rx_size) {
1653 			ret = -1;
1654 			goto out;
1655 		}
1656 
1657 		if (conn->conn_ops->DataDigest) {
1658 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1659 					ping_data, payload_length,
1660 					padding, cmd->pad_bytes,
1661 					(u8 *)&data_crc);
1662 
1663 			if (checksum != data_crc) {
1664 				pr_err("Ping data CRC32C DataDigest"
1665 				" 0x%08x does not match computed 0x%08x\n",
1666 					checksum, data_crc);
1667 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1668 					pr_err("Unable to recover from"
1669 					" NOPOUT Ping DataCRC failure while in"
1670 						" ERL=0.\n");
1671 					ret = -1;
1672 					goto out;
1673 				} else {
1674 					/*
1675 					 * Silently drop this PDU and let the
1676 					 * initiator plug the CmdSN gap.
1677 					 */
1678 					pr_debug("Dropping NOPOUT"
1679 					" Command CmdSN: 0x%08x due to"
1680 					" DataCRC error.\n", hdr->cmdsn);
1681 					ret = 0;
1682 					goto out;
1683 				}
1684 			} else {
1685 				pr_debug("Got CRC32C DataDigest"
1686 				" 0x%08x for %u bytes of ping data.\n",
1687 					checksum, payload_length);
1688 			}
1689 		}
1690 
1691 		ping_data[payload_length] = '\0';
1692 		/*
1693 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1694 		 */
1695 		cmd->buf_ptr = ping_data;
1696 		cmd->buf_ptr_size = payload_length;
1697 
1698 		pr_debug("Got %u bytes of NOPOUT ping"
1699 			" data.\n", payload_length);
1700 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1701 	}
1702 
1703 	return iscsit_process_nop_out(conn, cmd, hdr);
1704 out:
1705 	if (cmd)
1706 		iscsit_free_cmd(cmd, false);
1707 
1708 	kfree(ping_data);
1709 	return ret;
1710 }
1711 
1712 int
1713 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1714 			   unsigned char *buf)
1715 {
1716 	struct se_tmr_req *se_tmr;
1717 	struct iscsi_tmr_req *tmr_req;
1718 	struct iscsi_tm *hdr;
1719 	int out_of_order_cmdsn = 0, ret;
1720 	bool sess_ref = false;
1721 	u8 function;
1722 
1723 	hdr			= (struct iscsi_tm *) buf;
1724 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1725 	function = hdr->flags;
1726 
1727 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1728 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1729 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1730 		hdr->rtt, hdr->refcmdsn, conn->cid);
1731 
1732 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1733 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1734 	     hdr->rtt != RESERVED_ITT)) {
1735 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1736 		hdr->rtt = RESERVED_ITT;
1737 	}
1738 
1739 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1740 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1741 		pr_err("Task Management Request TASK_REASSIGN not"
1742 			" issued as immediate command, bad iSCSI Initiator"
1743 				"implementation\n");
1744 		return iscsit_add_reject_cmd(cmd,
1745 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1746 	}
1747 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1748 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1749 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1750 
1751 	cmd->data_direction = DMA_NONE;
1752 
1753 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1754 	if (!cmd->tmr_req) {
1755 		pr_err("Unable to allocate memory for"
1756 			" Task Management command!\n");
1757 		return iscsit_add_reject_cmd(cmd,
1758 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1759 					     buf);
1760 	}
1761 
1762 	/*
1763 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1764 	 * LIO-Target $FABRIC_MOD
1765 	 */
1766 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1767 
1768 		u8 tcm_function;
1769 		int ret;
1770 
1771 		transport_init_se_cmd(&cmd->se_cmd,
1772 				      &lio_target_fabric_configfs->tf_ops,
1773 				      conn->sess->se_sess, 0, DMA_NONE,
1774 				      MSG_SIMPLE_TAG, cmd->sense_buffer + 2);
1775 
1776 		target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
1777 		sess_ref = true;
1778 
1779 		switch (function) {
1780 		case ISCSI_TM_FUNC_ABORT_TASK:
1781 			tcm_function = TMR_ABORT_TASK;
1782 			break;
1783 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1784 			tcm_function = TMR_ABORT_TASK_SET;
1785 			break;
1786 		case ISCSI_TM_FUNC_CLEAR_ACA:
1787 			tcm_function = TMR_CLEAR_ACA;
1788 			break;
1789 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1790 			tcm_function = TMR_CLEAR_TASK_SET;
1791 			break;
1792 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1793 			tcm_function = TMR_LUN_RESET;
1794 			break;
1795 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1796 			tcm_function = TMR_TARGET_WARM_RESET;
1797 			break;
1798 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1799 			tcm_function = TMR_TARGET_COLD_RESET;
1800 			break;
1801 		default:
1802 			pr_err("Unknown iSCSI TMR Function:"
1803 			       " 0x%02x\n", function);
1804 			return iscsit_add_reject_cmd(cmd,
1805 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1806 		}
1807 
1808 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1809 					 tcm_function, GFP_KERNEL);
1810 		if (ret < 0)
1811 			return iscsit_add_reject_cmd(cmd,
1812 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1813 
1814 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1815 	}
1816 
1817 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1818 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1819 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1820 	cmd->init_task_tag	= hdr->itt;
1821 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1822 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1823 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1824 	se_tmr			= cmd->se_cmd.se_tmr_req;
1825 	tmr_req			= cmd->tmr_req;
1826 	/*
1827 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1828 	 */
1829 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1830 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1831 					       scsilun_to_int(&hdr->lun));
1832 		if (ret < 0) {
1833 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1834 			goto attach;
1835 		}
1836 	}
1837 
1838 	switch (function) {
1839 	case ISCSI_TM_FUNC_ABORT_TASK:
1840 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1841 		if (se_tmr->response)
1842 			goto attach;
1843 		break;
1844 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1845 	case ISCSI_TM_FUNC_CLEAR_ACA:
1846 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1847 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1848 		break;
1849 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1850 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1851 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1852 			goto attach;
1853 		}
1854 		break;
1855 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1856 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1857 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1858 			goto attach;
1859 		}
1860 		break;
1861 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1862 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1863 		/*
1864 		 * Perform sanity checks on the ExpDataSN only if the
1865 		 * TASK_REASSIGN was successful.
1866 		 */
1867 		if (se_tmr->response)
1868 			break;
1869 
1870 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1871 			return iscsit_add_reject_cmd(cmd,
1872 					ISCSI_REASON_BOOKMARK_INVALID, buf);
1873 		break;
1874 	default:
1875 		pr_err("Unknown TMR function: 0x%02x, protocol"
1876 			" error.\n", function);
1877 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1878 		goto attach;
1879 	}
1880 
1881 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1882 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1883 		se_tmr->call_transport = 1;
1884 attach:
1885 	spin_lock_bh(&conn->cmd_lock);
1886 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1887 	spin_unlock_bh(&conn->cmd_lock);
1888 
1889 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1890 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1891 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1892 			out_of_order_cmdsn = 1;
1893 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1894 			return 0;
1895 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1896 			return -1;
1897 	}
1898 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1899 
1900 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1901 		return 0;
1902 	/*
1903 	 * Found the referenced task, send to transport for processing.
1904 	 */
1905 	if (se_tmr->call_transport)
1906 		return transport_generic_handle_tmr(&cmd->se_cmd);
1907 
1908 	/*
1909 	 * Could not find the referenced LUN, task, or Task Management
1910 	 * command not authorized or supported.  Change state and
1911 	 * let the tx_thread send the response.
1912 	 *
1913 	 * For connection recovery, this is also the default action for
1914 	 * TMR TASK_REASSIGN.
1915 	 */
1916 	if (sess_ref) {
1917 		pr_debug("Handle TMR, using sess_ref=true check\n");
1918 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1919 	}
1920 
1921 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1922 	return 0;
1923 }
1924 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
1925 
1926 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1927 int
1928 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1929 		      struct iscsi_text *hdr)
1930 {
1931 	u32 payload_length = ntoh24(hdr->dlength);
1932 
1933 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1934 		pr_err("Unable to accept text parameter length: %u"
1935 			"greater than MaxXmitDataSegmentLength %u.\n",
1936 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1937 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1938 					 (unsigned char *)hdr);
1939 	}
1940 
1941 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
1942 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
1943 		pr_err("Multi sequence text commands currently not supported\n");
1944 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
1945 					(unsigned char *)hdr);
1946 	}
1947 
1948 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1949 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1950 		hdr->exp_statsn, payload_length);
1951 
1952 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1953 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1954 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1955 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
1956 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1957 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1958 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1959 	cmd->data_direction	= DMA_NONE;
1960 
1961 	return 0;
1962 }
1963 EXPORT_SYMBOL(iscsit_setup_text_cmd);
1964 
1965 int
1966 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1967 			struct iscsi_text *hdr)
1968 {
1969 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
1970 	int cmdsn_ret;
1971 
1972 	if (!text_in) {
1973 		pr_err("Unable to locate text_in buffer for sendtargets"
1974 		       " discovery\n");
1975 		goto reject;
1976 	}
1977 	if (strncmp("SendTargets", text_in, 11) != 0) {
1978 		pr_err("Received Text Data that is not"
1979 			" SendTargets, cannot continue.\n");
1980 		goto reject;
1981 	}
1982 	text_ptr = strchr(text_in, '=');
1983 	if (!text_ptr) {
1984 		pr_err("No \"=\" separator found in Text Data,"
1985 			"  cannot continue.\n");
1986 		goto reject;
1987 	}
1988 	if (!strncmp("=All", text_ptr, 4)) {
1989 		cmd->cmd_flags |= IFC_SENDTARGETS_ALL;
1990 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
1991 		   !strncmp("=eui.", text_ptr, 5)) {
1992 		cmd->cmd_flags |= IFC_SENDTARGETS_SINGLE;
1993 	} else {
1994 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
1995 		goto reject;
1996 	}
1997 
1998 	spin_lock_bh(&conn->cmd_lock);
1999 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2000 	spin_unlock_bh(&conn->cmd_lock);
2001 
2002 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2003 
2004 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2005 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2006 				(unsigned char *)hdr, hdr->cmdsn);
2007 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2008 			return -1;
2009 
2010 		return 0;
2011 	}
2012 
2013 	return iscsit_execute_cmd(cmd, 0);
2014 
2015 reject:
2016 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2017 				 (unsigned char *)hdr);
2018 }
2019 EXPORT_SYMBOL(iscsit_process_text_cmd);
2020 
2021 static int
2022 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2023 		       unsigned char *buf)
2024 {
2025 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2026 	char *text_in = NULL;
2027 	u32 payload_length = ntoh24(hdr->dlength);
2028 	int rx_size, rc;
2029 
2030 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2031 	if (rc < 0)
2032 		return 0;
2033 
2034 	rx_size = payload_length;
2035 	if (payload_length) {
2036 		u32 checksum = 0, data_crc = 0;
2037 		u32 padding = 0, pad_bytes = 0;
2038 		int niov = 0, rx_got;
2039 		struct kvec iov[3];
2040 
2041 		text_in = kzalloc(payload_length, GFP_KERNEL);
2042 		if (!text_in) {
2043 			pr_err("Unable to allocate memory for"
2044 				" incoming text parameters\n");
2045 			goto reject;
2046 		}
2047 		cmd->text_in_ptr = text_in;
2048 
2049 		memset(iov, 0, 3 * sizeof(struct kvec));
2050 		iov[niov].iov_base	= text_in;
2051 		iov[niov++].iov_len	= payload_length;
2052 
2053 		padding = ((-payload_length) & 3);
2054 		if (padding != 0) {
2055 			iov[niov].iov_base = &pad_bytes;
2056 			iov[niov++].iov_len  = padding;
2057 			rx_size += padding;
2058 			pr_debug("Receiving %u additional bytes"
2059 					" for padding.\n", padding);
2060 		}
2061 		if (conn->conn_ops->DataDigest) {
2062 			iov[niov].iov_base	= &checksum;
2063 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2064 			rx_size += ISCSI_CRC_LEN;
2065 		}
2066 
2067 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2068 		if (rx_got != rx_size)
2069 			goto reject;
2070 
2071 		if (conn->conn_ops->DataDigest) {
2072 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
2073 					text_in, payload_length,
2074 					padding, (u8 *)&pad_bytes,
2075 					(u8 *)&data_crc);
2076 
2077 			if (checksum != data_crc) {
2078 				pr_err("Text data CRC32C DataDigest"
2079 					" 0x%08x does not match computed"
2080 					" 0x%08x\n", checksum, data_crc);
2081 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2082 					pr_err("Unable to recover from"
2083 					" Text Data digest failure while in"
2084 						" ERL=0.\n");
2085 					goto reject;
2086 				} else {
2087 					/*
2088 					 * Silently drop this PDU and let the
2089 					 * initiator plug the CmdSN gap.
2090 					 */
2091 					pr_debug("Dropping Text"
2092 					" Command CmdSN: 0x%08x due to"
2093 					" DataCRC error.\n", hdr->cmdsn);
2094 					kfree(text_in);
2095 					return 0;
2096 				}
2097 			} else {
2098 				pr_debug("Got CRC32C DataDigest"
2099 					" 0x%08x for %u bytes of text data.\n",
2100 						checksum, payload_length);
2101 			}
2102 		}
2103 		text_in[payload_length - 1] = '\0';
2104 		pr_debug("Successfully read %d bytes of text"
2105 				" data.\n", payload_length);
2106 	}
2107 
2108 	return iscsit_process_text_cmd(conn, cmd, hdr);
2109 
2110 reject:
2111 	kfree(cmd->text_in_ptr);
2112 	cmd->text_in_ptr = NULL;
2113 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2114 }
2115 EXPORT_SYMBOL(iscsit_handle_text_cmd);
2116 
2117 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2118 {
2119 	struct iscsi_conn *conn_p;
2120 	struct iscsi_session *sess = conn->sess;
2121 
2122 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2123 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2124 
2125 	atomic_set(&sess->session_logout, 1);
2126 	atomic_set(&conn->conn_logout_remove, 1);
2127 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2128 
2129 	iscsit_inc_conn_usage_count(conn);
2130 	iscsit_inc_session_usage_count(sess);
2131 
2132 	spin_lock_bh(&sess->conn_lock);
2133 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2134 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2135 			continue;
2136 
2137 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2138 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2139 	}
2140 	spin_unlock_bh(&sess->conn_lock);
2141 
2142 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2143 
2144 	return 0;
2145 }
2146 
2147 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2148 {
2149 	struct iscsi_conn *l_conn;
2150 	struct iscsi_session *sess = conn->sess;
2151 
2152 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2153 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2154 
2155 	/*
2156 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2157 	 * can arrive on a connection with a differing CID.
2158 	 */
2159 	if (conn->cid == cmd->logout_cid) {
2160 		spin_lock_bh(&conn->state_lock);
2161 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2162 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2163 
2164 		atomic_set(&conn->conn_logout_remove, 1);
2165 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2166 		iscsit_inc_conn_usage_count(conn);
2167 
2168 		spin_unlock_bh(&conn->state_lock);
2169 	} else {
2170 		/*
2171 		 * Handle all different cid CLOSECONNECTION requests in
2172 		 * iscsit_logout_post_handler_diffcid() as to give enough
2173 		 * time for any non immediate command's CmdSN to be
2174 		 * acknowledged on the connection in question.
2175 		 *
2176 		 * Here we simply make sure the CID is still around.
2177 		 */
2178 		l_conn = iscsit_get_conn_from_cid(sess,
2179 				cmd->logout_cid);
2180 		if (!l_conn) {
2181 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2182 			iscsit_add_cmd_to_response_queue(cmd, conn,
2183 					cmd->i_state);
2184 			return 0;
2185 		}
2186 
2187 		iscsit_dec_conn_usage_count(l_conn);
2188 	}
2189 
2190 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2191 
2192 	return 0;
2193 }
2194 
2195 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2196 {
2197 	struct iscsi_session *sess = conn->sess;
2198 
2199 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2200 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2201 
2202 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2203 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2204 			" while ERL!=2.\n");
2205 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2206 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2207 		return 0;
2208 	}
2209 
2210 	if (conn->cid == cmd->logout_cid) {
2211 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2212 			" with CID: %hu on CID: %hu, implementation error.\n",
2213 				cmd->logout_cid, conn->cid);
2214 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2215 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2216 		return 0;
2217 	}
2218 
2219 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2220 
2221 	return 0;
2222 }
2223 
2224 int
2225 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2226 			unsigned char *buf)
2227 {
2228 	int cmdsn_ret, logout_remove = 0;
2229 	u8 reason_code = 0;
2230 	struct iscsi_logout *hdr;
2231 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2232 
2233 	hdr			= (struct iscsi_logout *) buf;
2234 	reason_code		= (hdr->flags & 0x7f);
2235 
2236 	if (tiqn) {
2237 		spin_lock(&tiqn->logout_stats.lock);
2238 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2239 			tiqn->logout_stats.normal_logouts++;
2240 		else
2241 			tiqn->logout_stats.abnormal_logouts++;
2242 		spin_unlock(&tiqn->logout_stats.lock);
2243 	}
2244 
2245 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2246 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2247 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2248 		hdr->cid, conn->cid);
2249 
2250 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2251 		pr_err("Received logout request on connection that"
2252 			" is not in logged in state, ignoring request.\n");
2253 		iscsit_free_cmd(cmd, false);
2254 		return 0;
2255 	}
2256 
2257 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2258 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2259 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2260 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2261 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2262 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2263 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2264 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2265 	cmd->logout_reason      = reason_code;
2266 	cmd->data_direction     = DMA_NONE;
2267 
2268 	/*
2269 	 * We need to sleep in these cases (by returning 1) until the Logout
2270 	 * Response gets sent in the tx thread.
2271 	 */
2272 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2273 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2274 	    be16_to_cpu(hdr->cid) == conn->cid))
2275 		logout_remove = 1;
2276 
2277 	spin_lock_bh(&conn->cmd_lock);
2278 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2279 	spin_unlock_bh(&conn->cmd_lock);
2280 
2281 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2282 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2283 
2284 	/*
2285 	 * Immediate commands are executed, well, immediately.
2286 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2287 	 */
2288 	if (cmd->immediate_cmd) {
2289 		int ret = iscsit_execute_cmd(cmd, 0);
2290 
2291 		if (ret < 0)
2292 			return ret;
2293 	} else {
2294 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2295 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2296 			logout_remove = 0;
2297 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2298 			return -1;
2299 	}
2300 
2301 	return logout_remove;
2302 }
2303 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2304 
2305 static int iscsit_handle_snack(
2306 	struct iscsi_conn *conn,
2307 	unsigned char *buf)
2308 {
2309 	struct iscsi_snack *hdr;
2310 
2311 	hdr			= (struct iscsi_snack *) buf;
2312 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2313 
2314 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2315 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2316 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2317 			hdr->begrun, hdr->runlength, conn->cid);
2318 
2319 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2320 		pr_err("Initiator sent SNACK request while in"
2321 			" ErrorRecoveryLevel=0.\n");
2322 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2323 					 buf);
2324 	}
2325 	/*
2326 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2327 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2328 	 */
2329 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2330 	case 0:
2331 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2332 			hdr->itt,
2333 			be32_to_cpu(hdr->ttt),
2334 			be32_to_cpu(hdr->begrun),
2335 			be32_to_cpu(hdr->runlength));
2336 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2337 		return iscsit_handle_status_snack(conn, hdr->itt,
2338 			be32_to_cpu(hdr->ttt),
2339 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2340 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2341 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2342 			be32_to_cpu(hdr->begrun),
2343 			be32_to_cpu(hdr->runlength));
2344 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2345 		/* FIXME: Support R-Data SNACK */
2346 		pr_err("R-Data SNACK Not Supported.\n");
2347 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2348 					 buf);
2349 	default:
2350 		pr_err("Unknown SNACK type 0x%02x, protocol"
2351 			" error.\n", hdr->flags & 0x0f);
2352 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2353 					 buf);
2354 	}
2355 
2356 	return 0;
2357 }
2358 
2359 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2360 {
2361 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2362 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2363 		wait_for_completion_interruptible_timeout(
2364 					&conn->rx_half_close_comp,
2365 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2366 	}
2367 }
2368 
2369 static int iscsit_handle_immediate_data(
2370 	struct iscsi_cmd *cmd,
2371 	struct iscsi_scsi_req *hdr,
2372 	u32 length)
2373 {
2374 	int iov_ret, rx_got = 0, rx_size = 0;
2375 	u32 checksum, iov_count = 0, padding = 0;
2376 	struct iscsi_conn *conn = cmd->conn;
2377 	struct kvec *iov;
2378 
2379 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2380 	if (iov_ret < 0)
2381 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2382 
2383 	rx_size = length;
2384 	iov_count = iov_ret;
2385 	iov = &cmd->iov_data[0];
2386 
2387 	padding = ((-length) & 3);
2388 	if (padding != 0) {
2389 		iov[iov_count].iov_base	= cmd->pad_bytes;
2390 		iov[iov_count++].iov_len = padding;
2391 		rx_size += padding;
2392 	}
2393 
2394 	if (conn->conn_ops->DataDigest) {
2395 		iov[iov_count].iov_base		= &checksum;
2396 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2397 		rx_size += ISCSI_CRC_LEN;
2398 	}
2399 
2400 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2401 
2402 	iscsit_unmap_iovec(cmd);
2403 
2404 	if (rx_got != rx_size) {
2405 		iscsit_rx_thread_wait_for_tcp(conn);
2406 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2407 	}
2408 
2409 	if (conn->conn_ops->DataDigest) {
2410 		u32 data_crc;
2411 
2412 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2413 						    cmd->write_data_done, length, padding,
2414 						    cmd->pad_bytes);
2415 
2416 		if (checksum != data_crc) {
2417 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2418 				" does not match computed 0x%08x\n", checksum,
2419 				data_crc);
2420 
2421 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2422 				pr_err("Unable to recover from"
2423 					" Immediate Data digest failure while"
2424 					" in ERL=0.\n");
2425 				iscsit_reject_cmd(cmd,
2426 						ISCSI_REASON_DATA_DIGEST_ERROR,
2427 						(unsigned char *)hdr);
2428 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2429 			} else {
2430 				iscsit_reject_cmd(cmd,
2431 						ISCSI_REASON_DATA_DIGEST_ERROR,
2432 						(unsigned char *)hdr);
2433 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2434 			}
2435 		} else {
2436 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2437 				" %u bytes of Immediate Data\n", checksum,
2438 				length);
2439 		}
2440 	}
2441 
2442 	cmd->write_data_done += length;
2443 
2444 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2445 		spin_lock_bh(&cmd->istate_lock);
2446 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2447 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2448 		spin_unlock_bh(&cmd->istate_lock);
2449 	}
2450 
2451 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2452 }
2453 
2454 /*
2455  *	Called with sess->conn_lock held.
2456  */
2457 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2458 	with active network interface */
2459 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2460 {
2461 	struct iscsi_cmd *cmd;
2462 	struct iscsi_conn *conn_p;
2463 
2464 	/*
2465 	 * Only send a Asynchronous Message on connections whos network
2466 	 * interface is still functional.
2467 	 */
2468 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2469 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2470 			iscsit_inc_conn_usage_count(conn_p);
2471 			break;
2472 		}
2473 	}
2474 
2475 	if (!conn_p)
2476 		return;
2477 
2478 	cmd = iscsit_allocate_cmd(conn_p, GFP_ATOMIC);
2479 	if (!cmd) {
2480 		iscsit_dec_conn_usage_count(conn_p);
2481 		return;
2482 	}
2483 
2484 	cmd->logout_cid = conn->cid;
2485 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2486 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2487 
2488 	spin_lock_bh(&conn_p->cmd_lock);
2489 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2490 	spin_unlock_bh(&conn_p->cmd_lock);
2491 
2492 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2493 	iscsit_dec_conn_usage_count(conn_p);
2494 }
2495 
2496 static int iscsit_send_conn_drop_async_message(
2497 	struct iscsi_cmd *cmd,
2498 	struct iscsi_conn *conn)
2499 {
2500 	struct iscsi_async *hdr;
2501 
2502 	cmd->tx_size = ISCSI_HDR_LEN;
2503 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2504 
2505 	hdr			= (struct iscsi_async *) cmd->pdu;
2506 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2507 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2508 	cmd->init_task_tag	= RESERVED_ITT;
2509 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2510 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2511 	cmd->stat_sn		= conn->stat_sn++;
2512 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2513 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2514 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2515 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2516 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2517 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2518 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2519 
2520 	if (conn->conn_ops->HeaderDigest) {
2521 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2522 
2523 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2524 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2525 
2526 		cmd->tx_size += ISCSI_CRC_LEN;
2527 		pr_debug("Attaching CRC32C HeaderDigest to"
2528 			" Async Message 0x%08x\n", *header_digest);
2529 	}
2530 
2531 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2532 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2533 	cmd->iov_misc_count		= 1;
2534 
2535 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2536 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2537 			cmd->logout_cid, conn->cid);
2538 	return 0;
2539 }
2540 
2541 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2542 {
2543 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2544 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2545 		wait_for_completion_interruptible_timeout(
2546 					&conn->tx_half_close_comp,
2547 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2548 	}
2549 }
2550 
2551 static void
2552 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2553 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2554 			bool set_statsn)
2555 {
2556 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2557 	hdr->flags		= datain->flags;
2558 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2559 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2560 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2561 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2562 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2563 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2564 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2565 		}
2566 	}
2567 	hton24(hdr->dlength, datain->length);
2568 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2569 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2570 				(struct scsi_lun *)&hdr->lun);
2571 	else
2572 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2573 
2574 	hdr->itt		= cmd->init_task_tag;
2575 
2576 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2577 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2578 	else
2579 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2580 	if (set_statsn)
2581 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2582 	else
2583 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2584 
2585 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2586 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2587 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2588 	hdr->offset		= cpu_to_be32(datain->offset);
2589 
2590 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2591 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2592 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2593 		ntohl(hdr->offset), datain->length, conn->cid);
2594 }
2595 
2596 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2597 {
2598 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2599 	struct iscsi_datain datain;
2600 	struct iscsi_datain_req *dr;
2601 	struct kvec *iov;
2602 	u32 iov_count = 0, tx_size = 0;
2603 	int eodr = 0, ret, iov_ret;
2604 	bool set_statsn = false;
2605 
2606 	memset(&datain, 0, sizeof(struct iscsi_datain));
2607 	dr = iscsit_get_datain_values(cmd, &datain);
2608 	if (!dr) {
2609 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2610 				cmd->init_task_tag);
2611 		return -1;
2612 	}
2613 	/*
2614 	 * Be paranoid and double check the logic for now.
2615 	 */
2616 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2617 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2618 			" datain.length: %u exceeds cmd->data_length: %u\n",
2619 			cmd->init_task_tag, datain.offset, datain.length,
2620 			cmd->se_cmd.data_length);
2621 		return -1;
2622 	}
2623 
2624 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2625 	/*
2626 	 * Special case for successfully execution w/ both DATAIN
2627 	 * and Sense Data.
2628 	 */
2629 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2630 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2631 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2632 	else {
2633 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2634 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2635 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2636 			cmd->stat_sn = conn->stat_sn++;
2637 			set_statsn = true;
2638 		} else if (dr->dr_complete ==
2639 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2640 			set_statsn = true;
2641 	}
2642 
2643 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2644 
2645 	iov = &cmd->iov_data[0];
2646 	iov[iov_count].iov_base	= cmd->pdu;
2647 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2648 	tx_size += ISCSI_HDR_LEN;
2649 
2650 	if (conn->conn_ops->HeaderDigest) {
2651 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2652 
2653 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
2654 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2655 
2656 		iov[0].iov_len += ISCSI_CRC_LEN;
2657 		tx_size += ISCSI_CRC_LEN;
2658 
2659 		pr_debug("Attaching CRC32 HeaderDigest"
2660 			" for DataIN PDU 0x%08x\n", *header_digest);
2661 	}
2662 
2663 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
2664 				datain.offset, datain.length);
2665 	if (iov_ret < 0)
2666 		return -1;
2667 
2668 	iov_count += iov_ret;
2669 	tx_size += datain.length;
2670 
2671 	cmd->padding = ((-datain.length) & 3);
2672 	if (cmd->padding) {
2673 		iov[iov_count].iov_base		= cmd->pad_bytes;
2674 		iov[iov_count++].iov_len	= cmd->padding;
2675 		tx_size += cmd->padding;
2676 
2677 		pr_debug("Attaching %u padding bytes\n",
2678 				cmd->padding);
2679 	}
2680 	if (conn->conn_ops->DataDigest) {
2681 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2682 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2683 
2684 		iov[iov_count].iov_base	= &cmd->data_crc;
2685 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2686 		tx_size += ISCSI_CRC_LEN;
2687 
2688 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2689 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2690 	}
2691 
2692 	cmd->iov_data_count = iov_count;
2693 	cmd->tx_size = tx_size;
2694 
2695 	/* sendpage is preferred but can't insert markers */
2696 	if (!conn->conn_ops->IFMarker)
2697 		ret = iscsit_fe_sendpage_sg(cmd, conn);
2698 	else
2699 		ret = iscsit_send_tx_data(cmd, conn, 0);
2700 
2701 	iscsit_unmap_iovec(cmd);
2702 
2703 	if (ret < 0) {
2704 		iscsit_tx_thread_wait_for_tcp(conn);
2705 		return ret;
2706 	}
2707 
2708 	if (dr->dr_complete) {
2709 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2710 				2 : 1;
2711 		iscsit_free_datain_req(cmd, dr);
2712 	}
2713 
2714 	return eodr;
2715 }
2716 
2717 int
2718 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2719 			struct iscsi_logout_rsp *hdr)
2720 {
2721 	struct iscsi_conn *logout_conn = NULL;
2722 	struct iscsi_conn_recovery *cr = NULL;
2723 	struct iscsi_session *sess = conn->sess;
2724 	/*
2725 	 * The actual shutting down of Sessions and/or Connections
2726 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2727 	 * is done in scsi_logout_post_handler().
2728 	 */
2729 	switch (cmd->logout_reason) {
2730 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2731 		pr_debug("iSCSI session logout successful, setting"
2732 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2733 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2734 		break;
2735 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2736 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2737 			break;
2738 		/*
2739 		 * For CLOSECONNECTION logout requests carrying
2740 		 * a matching logout CID -> local CID, the reference
2741 		 * for the local CID will have been incremented in
2742 		 * iscsi_logout_closeconnection().
2743 		 *
2744 		 * For CLOSECONNECTION logout requests carrying
2745 		 * a different CID than the connection it arrived
2746 		 * on, the connection responding to cmd->logout_cid
2747 		 * is stopped in iscsit_logout_post_handler_diffcid().
2748 		 */
2749 
2750 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2751 			" successful.\n", cmd->logout_cid, conn->cid);
2752 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2753 		break;
2754 	case ISCSI_LOGOUT_REASON_RECOVERY:
2755 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2756 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2757 			break;
2758 		/*
2759 		 * If the connection is still active from our point of view
2760 		 * force connection recovery to occur.
2761 		 */
2762 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2763 				cmd->logout_cid);
2764 		if (logout_conn) {
2765 			iscsit_connection_reinstatement_rcfr(logout_conn);
2766 			iscsit_dec_conn_usage_count(logout_conn);
2767 		}
2768 
2769 		cr = iscsit_get_inactive_connection_recovery_entry(
2770 				conn->sess, cmd->logout_cid);
2771 		if (!cr) {
2772 			pr_err("Unable to locate CID: %hu for"
2773 			" REMOVECONNFORRECOVERY Logout Request.\n",
2774 				cmd->logout_cid);
2775 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2776 			break;
2777 		}
2778 
2779 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2780 
2781 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2782 			" for recovery for CID: %hu on CID: %hu successful.\n",
2783 				cmd->logout_cid, conn->cid);
2784 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2785 		break;
2786 	default:
2787 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2788 				cmd->logout_reason);
2789 		return -1;
2790 	}
2791 
2792 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2793 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2794 	hdr->response		= cmd->logout_response;
2795 	hdr->itt		= cmd->init_task_tag;
2796 	cmd->stat_sn		= conn->stat_sn++;
2797 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2798 
2799 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2800 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2801 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2802 
2803 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2804 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2805 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2806 		cmd->logout_cid, conn->cid);
2807 
2808 	return 0;
2809 }
2810 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2811 
2812 static int
2813 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2814 {
2815 	struct kvec *iov;
2816 	int niov = 0, tx_size, rc;
2817 
2818 	rc = iscsit_build_logout_rsp(cmd, conn,
2819 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2820 	if (rc < 0)
2821 		return rc;
2822 
2823 	tx_size = ISCSI_HDR_LEN;
2824 	iov = &cmd->iov_misc[0];
2825 	iov[niov].iov_base	= cmd->pdu;
2826 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2827 
2828 	if (conn->conn_ops->HeaderDigest) {
2829 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2830 
2831 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, &cmd->pdu[0],
2832 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2833 
2834 		iov[0].iov_len += ISCSI_CRC_LEN;
2835 		tx_size += ISCSI_CRC_LEN;
2836 		pr_debug("Attaching CRC32C HeaderDigest to"
2837 			" Logout Response 0x%08x\n", *header_digest);
2838 	}
2839 	cmd->iov_misc_count = niov;
2840 	cmd->tx_size = tx_size;
2841 
2842 	return 0;
2843 }
2844 
2845 void
2846 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2847 		       struct iscsi_nopin *hdr, bool nopout_response)
2848 {
2849 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2850 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2851         hton24(hdr->dlength, cmd->buf_ptr_size);
2852 	if (nopout_response)
2853 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2854 	hdr->itt		= cmd->init_task_tag;
2855 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2856 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2857 				  conn->stat_sn;
2858 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2859 
2860 	if (nopout_response)
2861 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2862 
2863 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2864 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2865 
2866 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2867 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2868 		"Solicitied" : "Unsolicitied", cmd->init_task_tag,
2869 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2870 }
2871 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2872 
2873 /*
2874  *	Unsolicited NOPIN, either requesting a response or not.
2875  */
2876 static int iscsit_send_unsolicited_nopin(
2877 	struct iscsi_cmd *cmd,
2878 	struct iscsi_conn *conn,
2879 	int want_response)
2880 {
2881 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2882 	int tx_size = ISCSI_HDR_LEN, ret;
2883 
2884 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
2885 
2886 	if (conn->conn_ops->HeaderDigest) {
2887 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2888 
2889 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2890 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2891 
2892 		tx_size += ISCSI_CRC_LEN;
2893 		pr_debug("Attaching CRC32C HeaderDigest to"
2894 			" NopIN 0x%08x\n", *header_digest);
2895 	}
2896 
2897 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2898 	cmd->iov_misc[0].iov_len	= tx_size;
2899 	cmd->iov_misc_count	= 1;
2900 	cmd->tx_size		= tx_size;
2901 
2902 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2903 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2904 
2905 	ret = iscsit_send_tx_data(cmd, conn, 1);
2906 	if (ret < 0) {
2907 		iscsit_tx_thread_wait_for_tcp(conn);
2908 		return ret;
2909 	}
2910 
2911 	spin_lock_bh(&cmd->istate_lock);
2912 	cmd->i_state = want_response ?
2913 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2914 	spin_unlock_bh(&cmd->istate_lock);
2915 
2916 	return 0;
2917 }
2918 
2919 static int
2920 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2921 {
2922 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2923 	struct kvec *iov;
2924 	u32 padding = 0;
2925 	int niov = 0, tx_size;
2926 
2927 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
2928 
2929 	tx_size = ISCSI_HDR_LEN;
2930 	iov = &cmd->iov_misc[0];
2931 	iov[niov].iov_base	= cmd->pdu;
2932 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2933 
2934 	if (conn->conn_ops->HeaderDigest) {
2935 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2936 
2937 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2938 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2939 
2940 		iov[0].iov_len += ISCSI_CRC_LEN;
2941 		tx_size += ISCSI_CRC_LEN;
2942 		pr_debug("Attaching CRC32C HeaderDigest"
2943 			" to NopIn 0x%08x\n", *header_digest);
2944 	}
2945 
2946 	/*
2947 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2948 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2949 	 */
2950 	if (cmd->buf_ptr_size) {
2951 		iov[niov].iov_base	= cmd->buf_ptr;
2952 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2953 		tx_size += cmd->buf_ptr_size;
2954 
2955 		pr_debug("Echoing back %u bytes of ping"
2956 			" data.\n", cmd->buf_ptr_size);
2957 
2958 		padding = ((-cmd->buf_ptr_size) & 3);
2959 		if (padding != 0) {
2960 			iov[niov].iov_base = &cmd->pad_bytes;
2961 			iov[niov++].iov_len = padding;
2962 			tx_size += padding;
2963 			pr_debug("Attaching %u additional"
2964 				" padding bytes.\n", padding);
2965 		}
2966 		if (conn->conn_ops->DataDigest) {
2967 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2968 				cmd->buf_ptr, cmd->buf_ptr_size,
2969 				padding, (u8 *)&cmd->pad_bytes,
2970 				(u8 *)&cmd->data_crc);
2971 
2972 			iov[niov].iov_base = &cmd->data_crc;
2973 			iov[niov++].iov_len = ISCSI_CRC_LEN;
2974 			tx_size += ISCSI_CRC_LEN;
2975 			pr_debug("Attached DataDigest for %u"
2976 				" bytes of ping data, CRC 0x%08x\n",
2977 				cmd->buf_ptr_size, cmd->data_crc);
2978 		}
2979 	}
2980 
2981 	cmd->iov_misc_count = niov;
2982 	cmd->tx_size = tx_size;
2983 
2984 	return 0;
2985 }
2986 
2987 static int iscsit_send_r2t(
2988 	struct iscsi_cmd *cmd,
2989 	struct iscsi_conn *conn)
2990 {
2991 	int tx_size = 0;
2992 	struct iscsi_r2t *r2t;
2993 	struct iscsi_r2t_rsp *hdr;
2994 	int ret;
2995 
2996 	r2t = iscsit_get_r2t_from_list(cmd);
2997 	if (!r2t)
2998 		return -1;
2999 
3000 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3001 	memset(hdr, 0, ISCSI_HDR_LEN);
3002 	hdr->opcode		= ISCSI_OP_R2T;
3003 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3004 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3005 			(struct scsi_lun *)&hdr->lun);
3006 	hdr->itt		= cmd->init_task_tag;
3007 	spin_lock_bh(&conn->sess->ttt_lock);
3008 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
3009 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
3010 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
3011 	spin_unlock_bh(&conn->sess->ttt_lock);
3012 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3013 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3014 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3015 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3016 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3017 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3018 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3019 
3020 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3021 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3022 	tx_size += ISCSI_HDR_LEN;
3023 
3024 	if (conn->conn_ops->HeaderDigest) {
3025 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3026 
3027 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3028 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3029 
3030 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3031 		tx_size += ISCSI_CRC_LEN;
3032 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
3033 			" PDU 0x%08x\n", *header_digest);
3034 	}
3035 
3036 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3037 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3038 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3039 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3040 			r2t->offset, r2t->xfer_len, conn->cid);
3041 
3042 	cmd->iov_misc_count = 1;
3043 	cmd->tx_size = tx_size;
3044 
3045 	spin_lock_bh(&cmd->r2t_lock);
3046 	r2t->sent_r2t = 1;
3047 	spin_unlock_bh(&cmd->r2t_lock);
3048 
3049 	ret = iscsit_send_tx_data(cmd, conn, 1);
3050 	if (ret < 0) {
3051 		iscsit_tx_thread_wait_for_tcp(conn);
3052 		return ret;
3053 	}
3054 
3055 	spin_lock_bh(&cmd->dataout_timeout_lock);
3056 	iscsit_start_dataout_timer(cmd, conn);
3057 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3058 
3059 	return 0;
3060 }
3061 
3062 /*
3063  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3064  *		connection recovery.
3065  */
3066 int iscsit_build_r2ts_for_cmd(
3067 	struct iscsi_conn *conn,
3068 	struct iscsi_cmd *cmd,
3069 	bool recovery)
3070 {
3071 	int first_r2t = 1;
3072 	u32 offset = 0, xfer_len = 0;
3073 
3074 	spin_lock_bh(&cmd->r2t_lock);
3075 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3076 		spin_unlock_bh(&cmd->r2t_lock);
3077 		return 0;
3078 	}
3079 
3080 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3081 	    !recovery)
3082 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3083 
3084 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3085 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3086 			offset = cmd->r2t_offset;
3087 
3088 			if (first_r2t && recovery) {
3089 				int new_data_end = offset +
3090 					conn->sess->sess_ops->MaxBurstLength -
3091 					cmd->next_burst_len;
3092 
3093 				if (new_data_end > cmd->se_cmd.data_length)
3094 					xfer_len = cmd->se_cmd.data_length - offset;
3095 				else
3096 					xfer_len =
3097 						conn->sess->sess_ops->MaxBurstLength -
3098 						cmd->next_burst_len;
3099 			} else {
3100 				int new_data_end = offset +
3101 					conn->sess->sess_ops->MaxBurstLength;
3102 
3103 				if (new_data_end > cmd->se_cmd.data_length)
3104 					xfer_len = cmd->se_cmd.data_length - offset;
3105 				else
3106 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3107 			}
3108 			cmd->r2t_offset += xfer_len;
3109 
3110 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3111 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3112 		} else {
3113 			struct iscsi_seq *seq;
3114 
3115 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3116 			if (!seq) {
3117 				spin_unlock_bh(&cmd->r2t_lock);
3118 				return -1;
3119 			}
3120 
3121 			offset = seq->offset;
3122 			xfer_len = seq->xfer_len;
3123 
3124 			if (cmd->seq_send_order == cmd->seq_count)
3125 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3126 		}
3127 		cmd->outstanding_r2ts++;
3128 		first_r2t = 0;
3129 
3130 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3131 			spin_unlock_bh(&cmd->r2t_lock);
3132 			return -1;
3133 		}
3134 
3135 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3136 			break;
3137 	}
3138 	spin_unlock_bh(&cmd->r2t_lock);
3139 
3140 	return 0;
3141 }
3142 
3143 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3144 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3145 {
3146 	if (inc_stat_sn)
3147 		cmd->stat_sn = conn->stat_sn++;
3148 
3149 	atomic_long_inc(&conn->sess->rsp_pdus);
3150 
3151 	memset(hdr, 0, ISCSI_HDR_LEN);
3152 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3153 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3154 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3155 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3156 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3157 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3158 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3159 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3160 	}
3161 	hdr->response		= cmd->iscsi_response;
3162 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3163 	hdr->itt		= cmd->init_task_tag;
3164 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3165 
3166 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3167 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3168 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3169 
3170 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3171 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3172 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3173 		cmd->se_cmd.scsi_status, conn->cid);
3174 }
3175 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3176 
3177 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3178 {
3179 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3180 	struct kvec *iov;
3181 	u32 padding = 0, tx_size = 0;
3182 	int iov_count = 0;
3183 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3184 
3185 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3186 
3187 	iov = &cmd->iov_misc[0];
3188 	iov[iov_count].iov_base	= cmd->pdu;
3189 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3190 	tx_size += ISCSI_HDR_LEN;
3191 
3192 	/*
3193 	 * Attach SENSE DATA payload to iSCSI Response PDU
3194 	 */
3195 	if (cmd->se_cmd.sense_buffer &&
3196 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3197 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3198 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3199 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3200 
3201 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3202 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3203 		iov[iov_count].iov_base	= cmd->sense_buffer;
3204 		iov[iov_count++].iov_len =
3205 				(cmd->se_cmd.scsi_sense_length + padding);
3206 		tx_size += cmd->se_cmd.scsi_sense_length;
3207 
3208 		if (padding) {
3209 			memset(cmd->sense_buffer +
3210 				cmd->se_cmd.scsi_sense_length, 0, padding);
3211 			tx_size += padding;
3212 			pr_debug("Adding %u bytes of padding to"
3213 				" SENSE.\n", padding);
3214 		}
3215 
3216 		if (conn->conn_ops->DataDigest) {
3217 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3218 				cmd->sense_buffer,
3219 				(cmd->se_cmd.scsi_sense_length + padding),
3220 				0, NULL, (u8 *)&cmd->data_crc);
3221 
3222 			iov[iov_count].iov_base    = &cmd->data_crc;
3223 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3224 			tx_size += ISCSI_CRC_LEN;
3225 
3226 			pr_debug("Attaching CRC32 DataDigest for"
3227 				" SENSE, %u bytes CRC 0x%08x\n",
3228 				(cmd->se_cmd.scsi_sense_length + padding),
3229 				cmd->data_crc);
3230 		}
3231 
3232 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3233 				" Response PDU\n",
3234 				cmd->se_cmd.scsi_sense_length);
3235 	}
3236 
3237 	if (conn->conn_ops->HeaderDigest) {
3238 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3239 
3240 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
3241 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3242 
3243 		iov[0].iov_len += ISCSI_CRC_LEN;
3244 		tx_size += ISCSI_CRC_LEN;
3245 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3246 				" PDU 0x%08x\n", *header_digest);
3247 	}
3248 
3249 	cmd->iov_misc_count = iov_count;
3250 	cmd->tx_size = tx_size;
3251 
3252 	return 0;
3253 }
3254 
3255 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3256 {
3257 	switch (se_tmr->response) {
3258 	case TMR_FUNCTION_COMPLETE:
3259 		return ISCSI_TMF_RSP_COMPLETE;
3260 	case TMR_TASK_DOES_NOT_EXIST:
3261 		return ISCSI_TMF_RSP_NO_TASK;
3262 	case TMR_LUN_DOES_NOT_EXIST:
3263 		return ISCSI_TMF_RSP_NO_LUN;
3264 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3265 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3266 	case TMR_FUNCTION_REJECTED:
3267 	default:
3268 		return ISCSI_TMF_RSP_REJECTED;
3269 	}
3270 }
3271 
3272 void
3273 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3274 			  struct iscsi_tm_rsp *hdr)
3275 {
3276 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3277 
3278 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3279 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3280 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3281 	hdr->itt		= cmd->init_task_tag;
3282 	cmd->stat_sn		= conn->stat_sn++;
3283 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3284 
3285 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3286 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3287 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3288 
3289 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3290 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3291 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3292 }
3293 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3294 
3295 static int
3296 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3297 {
3298 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3299 	u32 tx_size = 0;
3300 
3301 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3302 
3303 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3304 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3305 	tx_size += ISCSI_HDR_LEN;
3306 
3307 	if (conn->conn_ops->HeaderDigest) {
3308 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3309 
3310 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3311 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3312 
3313 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3314 		tx_size += ISCSI_CRC_LEN;
3315 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3316 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3317 	}
3318 
3319 	cmd->iov_misc_count = 1;
3320 	cmd->tx_size = tx_size;
3321 
3322 	return 0;
3323 }
3324 
3325 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3326 {
3327 	bool ret = false;
3328 
3329 	if (np->np_sockaddr.ss_family == AF_INET6) {
3330 		const struct sockaddr_in6 sin6 = {
3331 			.sin6_addr = IN6ADDR_ANY_INIT };
3332 		struct sockaddr_in6 *sock_in6 =
3333 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3334 
3335 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3336 				sin6.sin6_addr.s6_addr, 16))
3337 			ret = true;
3338 	} else {
3339 		struct sockaddr_in * sock_in =
3340 			(struct sockaddr_in *)&np->np_sockaddr;
3341 
3342 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3343 			ret = true;
3344 	}
3345 
3346 	return ret;
3347 }
3348 
3349 #define SENDTARGETS_BUF_LIMIT 32768U
3350 
3351 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3352 {
3353 	char *payload = NULL;
3354 	struct iscsi_conn *conn = cmd->conn;
3355 	struct iscsi_portal_group *tpg;
3356 	struct iscsi_tiqn *tiqn;
3357 	struct iscsi_tpg_np *tpg_np;
3358 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3359 	int target_name_printed;
3360 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3361 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3362 
3363 	buffer_len = max(conn->conn_ops->MaxRecvDataSegmentLength,
3364 			 SENDTARGETS_BUF_LIMIT);
3365 
3366 	payload = kzalloc(buffer_len, GFP_KERNEL);
3367 	if (!payload) {
3368 		pr_err("Unable to allocate memory for sendtargets"
3369 				" response.\n");
3370 		return -ENOMEM;
3371 	}
3372 	/*
3373 	 * Locate pointer to iqn./eui. string for IFC_SENDTARGETS_SINGLE
3374 	 * explicit case..
3375 	 */
3376 	if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) {
3377 		text_ptr = strchr(text_in, '=');
3378 		if (!text_ptr) {
3379 			pr_err("Unable to locate '=' string in text_in:"
3380 			       " %s\n", text_in);
3381 			kfree(payload);
3382 			return -EINVAL;
3383 		}
3384 		/*
3385 		 * Skip over '=' character..
3386 		 */
3387 		text_ptr += 1;
3388 	}
3389 
3390 	spin_lock(&tiqn_lock);
3391 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3392 		if ((cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) &&
3393 		     strcmp(tiqn->tiqn, text_ptr)) {
3394 			continue;
3395 		}
3396 
3397 		target_name_printed = 0;
3398 
3399 		spin_lock(&tiqn->tiqn_tpg_lock);
3400 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3401 
3402 			/* If demo_mode_discovery=0 and generate_node_acls=0
3403 			 * (demo mode dislabed) do not return
3404 			 * TargetName+TargetAddress unless a NodeACL exists.
3405 			 */
3406 
3407 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3408 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3409 			    (!core_tpg_get_initiator_node_acl(&tpg->tpg_se_tpg,
3410 				cmd->conn->sess->sess_ops->InitiatorName))) {
3411 				continue;
3412 			}
3413 
3414 			spin_lock(&tpg->tpg_state_lock);
3415 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3416 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3417 				spin_unlock(&tpg->tpg_state_lock);
3418 				continue;
3419 			}
3420 			spin_unlock(&tpg->tpg_state_lock);
3421 
3422 			spin_lock(&tpg->tpg_np_lock);
3423 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3424 						tpg_np_list) {
3425 				struct iscsi_np *np = tpg_np->tpg_np;
3426 				bool inaddr_any = iscsit_check_inaddr_any(np);
3427 
3428 				if (!target_name_printed) {
3429 					len = sprintf(buf, "TargetName=%s",
3430 						      tiqn->tiqn);
3431 					len += 1;
3432 
3433 					if ((len + payload_len) > buffer_len) {
3434 						spin_unlock(&tpg->tpg_np_lock);
3435 						spin_unlock(&tiqn->tiqn_tpg_lock);
3436 						end_of_buf = 1;
3437 						goto eob;
3438 					}
3439 					memcpy(payload + payload_len, buf, len);
3440 					payload_len += len;
3441 					target_name_printed = 1;
3442 				}
3443 
3444 				len = sprintf(buf, "TargetAddress="
3445 					"%s:%hu,%hu",
3446 					(inaddr_any == false) ?
3447 						np->np_ip : conn->local_ip,
3448 					(inaddr_any == false) ?
3449 						np->np_port : conn->local_port,
3450 					tpg->tpgt);
3451 				len += 1;
3452 
3453 				if ((len + payload_len) > buffer_len) {
3454 					spin_unlock(&tpg->tpg_np_lock);
3455 					spin_unlock(&tiqn->tiqn_tpg_lock);
3456 					end_of_buf = 1;
3457 					goto eob;
3458 				}
3459 				memcpy(payload + payload_len, buf, len);
3460 				payload_len += len;
3461 			}
3462 			spin_unlock(&tpg->tpg_np_lock);
3463 		}
3464 		spin_unlock(&tiqn->tiqn_tpg_lock);
3465 eob:
3466 		if (end_of_buf)
3467 			break;
3468 
3469 		if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE)
3470 			break;
3471 	}
3472 	spin_unlock(&tiqn_lock);
3473 
3474 	cmd->buf_ptr = payload;
3475 
3476 	return payload_len;
3477 }
3478 
3479 int
3480 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3481 		      struct iscsi_text_rsp *hdr)
3482 {
3483 	int text_length, padding;
3484 
3485 	text_length = iscsit_build_sendtargets_response(cmd);
3486 	if (text_length < 0)
3487 		return text_length;
3488 
3489 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3490 	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3491 	padding = ((-text_length) & 3);
3492 	hton24(hdr->dlength, text_length);
3493 	hdr->itt = cmd->init_task_tag;
3494 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3495 	cmd->stat_sn = conn->stat_sn++;
3496 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3497 
3498 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3499 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3500 	hdr->max_cmdsn = cpu_to_be32(conn->sess->max_cmd_sn);
3501 
3502 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3503 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3504 		text_length, conn->cid);
3505 
3506 	return text_length + padding;
3507 }
3508 EXPORT_SYMBOL(iscsit_build_text_rsp);
3509 
3510 /*
3511  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3512  *	MaxRecvDataSegmentLength.
3513  */
3514 static int iscsit_send_text_rsp(
3515 	struct iscsi_cmd *cmd,
3516 	struct iscsi_conn *conn)
3517 {
3518 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3519 	struct kvec *iov;
3520 	u32 tx_size = 0;
3521 	int text_length, iov_count = 0, rc;
3522 
3523 	rc = iscsit_build_text_rsp(cmd, conn, hdr);
3524 	if (rc < 0)
3525 		return rc;
3526 
3527 	text_length = rc;
3528 	iov = &cmd->iov_misc[0];
3529 	iov[iov_count].iov_base = cmd->pdu;
3530 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3531 	iov[iov_count].iov_base	= cmd->buf_ptr;
3532 	iov[iov_count++].iov_len = text_length;
3533 
3534 	tx_size += (ISCSI_HDR_LEN + text_length);
3535 
3536 	if (conn->conn_ops->HeaderDigest) {
3537 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3538 
3539 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3540 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3541 
3542 		iov[0].iov_len += ISCSI_CRC_LEN;
3543 		tx_size += ISCSI_CRC_LEN;
3544 		pr_debug("Attaching CRC32 HeaderDigest for"
3545 			" Text Response PDU 0x%08x\n", *header_digest);
3546 	}
3547 
3548 	if (conn->conn_ops->DataDigest) {
3549 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3550 				cmd->buf_ptr, text_length,
3551 				0, NULL, (u8 *)&cmd->data_crc);
3552 
3553 		iov[iov_count].iov_base	= &cmd->data_crc;
3554 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3555 		tx_size	+= ISCSI_CRC_LEN;
3556 
3557 		pr_debug("Attaching DataDigest for %u bytes of text"
3558 			" data, CRC 0x%08x\n", text_length,
3559 			cmd->data_crc);
3560 	}
3561 
3562 	cmd->iov_misc_count = iov_count;
3563 	cmd->tx_size = tx_size;
3564 
3565 	return 0;
3566 }
3567 
3568 void
3569 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3570 		    struct iscsi_reject *hdr)
3571 {
3572 	hdr->opcode		= ISCSI_OP_REJECT;
3573 	hdr->reason		= cmd->reject_reason;
3574 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3575 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3576 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3577 	cmd->stat_sn		= conn->stat_sn++;
3578 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3579 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3580 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3581 
3582 }
3583 EXPORT_SYMBOL(iscsit_build_reject);
3584 
3585 static int iscsit_send_reject(
3586 	struct iscsi_cmd *cmd,
3587 	struct iscsi_conn *conn)
3588 {
3589 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3590 	struct kvec *iov;
3591 	u32 iov_count = 0, tx_size;
3592 
3593 	iscsit_build_reject(cmd, conn, hdr);
3594 
3595 	iov = &cmd->iov_misc[0];
3596 	iov[iov_count].iov_base = cmd->pdu;
3597 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3598 	iov[iov_count].iov_base = cmd->buf_ptr;
3599 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3600 
3601 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3602 
3603 	if (conn->conn_ops->HeaderDigest) {
3604 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3605 
3606 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3607 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3608 
3609 		iov[0].iov_len += ISCSI_CRC_LEN;
3610 		tx_size += ISCSI_CRC_LEN;
3611 		pr_debug("Attaching CRC32 HeaderDigest for"
3612 			" REJECT PDU 0x%08x\n", *header_digest);
3613 	}
3614 
3615 	if (conn->conn_ops->DataDigest) {
3616 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->buf_ptr,
3617 				ISCSI_HDR_LEN, 0, NULL, (u8 *)&cmd->data_crc);
3618 
3619 		iov[iov_count].iov_base = &cmd->data_crc;
3620 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3621 		tx_size += ISCSI_CRC_LEN;
3622 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3623 				" PDU 0x%08x\n", cmd->data_crc);
3624 	}
3625 
3626 	cmd->iov_misc_count = iov_count;
3627 	cmd->tx_size = tx_size;
3628 
3629 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3630 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3631 
3632 	return 0;
3633 }
3634 
3635 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3636 {
3637 	struct iscsi_thread_set *ts = conn->thread_set;
3638 	int ord, cpu;
3639 	/*
3640 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3641 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3642 	 *
3643 	 * Here we use thread_id to determine which CPU that this
3644 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3645 	 * execute upon.
3646 	 */
3647 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3648 	for_each_online_cpu(cpu) {
3649 		if (ord-- == 0) {
3650 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3651 			return;
3652 		}
3653 	}
3654 	/*
3655 	 * This should never be reached..
3656 	 */
3657 	dump_stack();
3658 	cpumask_setall(conn->conn_cpumask);
3659 }
3660 
3661 static inline void iscsit_thread_check_cpumask(
3662 	struct iscsi_conn *conn,
3663 	struct task_struct *p,
3664 	int mode)
3665 {
3666 	char buf[128];
3667 	/*
3668 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3669 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3670 	 */
3671 	if (mode == 1) {
3672 		if (!conn->conn_tx_reset_cpumask)
3673 			return;
3674 		conn->conn_tx_reset_cpumask = 0;
3675 	} else {
3676 		if (!conn->conn_rx_reset_cpumask)
3677 			return;
3678 		conn->conn_rx_reset_cpumask = 0;
3679 	}
3680 	/*
3681 	 * Update the CPU mask for this single kthread so that
3682 	 * both TX and RX kthreads are scheduled to run on the
3683 	 * same CPU.
3684 	 */
3685 	memset(buf, 0, 128);
3686 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3687 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3688 }
3689 
3690 static int
3691 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3692 {
3693 	int ret;
3694 
3695 	switch (state) {
3696 	case ISTATE_SEND_R2T:
3697 		ret = iscsit_send_r2t(cmd, conn);
3698 		if (ret < 0)
3699 			goto err;
3700 		break;
3701 	case ISTATE_REMOVE:
3702 		spin_lock_bh(&conn->cmd_lock);
3703 		list_del(&cmd->i_conn_node);
3704 		spin_unlock_bh(&conn->cmd_lock);
3705 
3706 		iscsit_free_cmd(cmd, false);
3707 		break;
3708 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3709 		iscsit_mod_nopin_response_timer(conn);
3710 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3711 		if (ret < 0)
3712 			goto err;
3713 		break;
3714 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3715 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3716 		if (ret < 0)
3717 			goto err;
3718 		break;
3719 	default:
3720 		pr_err("Unknown Opcode: 0x%02x ITT:"
3721 		       " 0x%08x, i_state: %d on CID: %hu\n",
3722 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3723 		       conn->cid);
3724 		goto err;
3725 	}
3726 
3727 	return 0;
3728 
3729 err:
3730 	return -1;
3731 }
3732 
3733 static int
3734 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3735 {
3736 	struct iscsit_transport *t = conn->conn_transport;
3737 	struct iscsi_queue_req *qr;
3738 	struct iscsi_cmd *cmd;
3739 	u8 state;
3740 	int ret;
3741 
3742 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3743 		atomic_set(&conn->check_immediate_queue, 0);
3744 		cmd = qr->cmd;
3745 		state = qr->state;
3746 		kmem_cache_free(lio_qr_cache, qr);
3747 
3748 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3749 		if (ret < 0)
3750 			return ret;
3751 	}
3752 
3753 	return 0;
3754 }
3755 
3756 static int
3757 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3758 {
3759 	int ret;
3760 
3761 check_rsp_state:
3762 	switch (state) {
3763 	case ISTATE_SEND_DATAIN:
3764 		ret = iscsit_send_datain(cmd, conn);
3765 		if (ret < 0)
3766 			goto err;
3767 		else if (!ret)
3768 			/* more drs */
3769 			goto check_rsp_state;
3770 		else if (ret == 1) {
3771 			/* all done */
3772 			spin_lock_bh(&cmd->istate_lock);
3773 			cmd->i_state = ISTATE_SENT_STATUS;
3774 			spin_unlock_bh(&cmd->istate_lock);
3775 
3776 			if (atomic_read(&conn->check_immediate_queue))
3777 				return 1;
3778 
3779 			return 0;
3780 		} else if (ret == 2) {
3781 			/* Still must send status,
3782 			   SCF_TRANSPORT_TASK_SENSE was set */
3783 			spin_lock_bh(&cmd->istate_lock);
3784 			cmd->i_state = ISTATE_SEND_STATUS;
3785 			spin_unlock_bh(&cmd->istate_lock);
3786 			state = ISTATE_SEND_STATUS;
3787 			goto check_rsp_state;
3788 		}
3789 
3790 		break;
3791 	case ISTATE_SEND_STATUS:
3792 	case ISTATE_SEND_STATUS_RECOVERY:
3793 		ret = iscsit_send_response(cmd, conn);
3794 		break;
3795 	case ISTATE_SEND_LOGOUTRSP:
3796 		ret = iscsit_send_logout(cmd, conn);
3797 		break;
3798 	case ISTATE_SEND_ASYNCMSG:
3799 		ret = iscsit_send_conn_drop_async_message(
3800 			cmd, conn);
3801 		break;
3802 	case ISTATE_SEND_NOPIN:
3803 		ret = iscsit_send_nopin(cmd, conn);
3804 		break;
3805 	case ISTATE_SEND_REJECT:
3806 		ret = iscsit_send_reject(cmd, conn);
3807 		break;
3808 	case ISTATE_SEND_TASKMGTRSP:
3809 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3810 		if (ret != 0)
3811 			break;
3812 		ret = iscsit_tmr_post_handler(cmd, conn);
3813 		if (ret != 0)
3814 			iscsit_fall_back_to_erl0(conn->sess);
3815 		break;
3816 	case ISTATE_SEND_TEXTRSP:
3817 		ret = iscsit_send_text_rsp(cmd, conn);
3818 		break;
3819 	default:
3820 		pr_err("Unknown Opcode: 0x%02x ITT:"
3821 		       " 0x%08x, i_state: %d on CID: %hu\n",
3822 		       cmd->iscsi_opcode, cmd->init_task_tag,
3823 		       state, conn->cid);
3824 		goto err;
3825 	}
3826 	if (ret < 0)
3827 		goto err;
3828 
3829 	if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3830 		iscsit_tx_thread_wait_for_tcp(conn);
3831 		iscsit_unmap_iovec(cmd);
3832 		goto err;
3833 	}
3834 	iscsit_unmap_iovec(cmd);
3835 
3836 	switch (state) {
3837 	case ISTATE_SEND_LOGOUTRSP:
3838 		if (!iscsit_logout_post_handler(cmd, conn))
3839 			goto restart;
3840 		/* fall through */
3841 	case ISTATE_SEND_STATUS:
3842 	case ISTATE_SEND_ASYNCMSG:
3843 	case ISTATE_SEND_NOPIN:
3844 	case ISTATE_SEND_STATUS_RECOVERY:
3845 	case ISTATE_SEND_TEXTRSP:
3846 	case ISTATE_SEND_TASKMGTRSP:
3847 	case ISTATE_SEND_REJECT:
3848 		spin_lock_bh(&cmd->istate_lock);
3849 		cmd->i_state = ISTATE_SENT_STATUS;
3850 		spin_unlock_bh(&cmd->istate_lock);
3851 		break;
3852 	default:
3853 		pr_err("Unknown Opcode: 0x%02x ITT:"
3854 		       " 0x%08x, i_state: %d on CID: %hu\n",
3855 		       cmd->iscsi_opcode, cmd->init_task_tag,
3856 		       cmd->i_state, conn->cid);
3857 		goto err;
3858 	}
3859 
3860 	if (atomic_read(&conn->check_immediate_queue))
3861 		return 1;
3862 
3863 	return 0;
3864 
3865 err:
3866 	return -1;
3867 restart:
3868 	return -EAGAIN;
3869 }
3870 
3871 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3872 {
3873 	struct iscsit_transport *t = conn->conn_transport;
3874 	struct iscsi_queue_req *qr;
3875 	struct iscsi_cmd *cmd;
3876 	u8 state;
3877 	int ret;
3878 
3879 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3880 		cmd = qr->cmd;
3881 		state = qr->state;
3882 		kmem_cache_free(lio_qr_cache, qr);
3883 
3884 		ret = t->iscsit_response_queue(conn, cmd, state);
3885 		if (ret == 1 || ret < 0)
3886 			return ret;
3887 	}
3888 
3889 	return 0;
3890 }
3891 
3892 int iscsi_target_tx_thread(void *arg)
3893 {
3894 	int ret = 0;
3895 	struct iscsi_conn *conn;
3896 	struct iscsi_thread_set *ts = arg;
3897 	/*
3898 	 * Allow ourselves to be interrupted by SIGINT so that a
3899 	 * connection recovery / failure event can be triggered externally.
3900 	 */
3901 	allow_signal(SIGINT);
3902 
3903 restart:
3904 	conn = iscsi_tx_thread_pre_handler(ts);
3905 	if (!conn)
3906 		goto out;
3907 
3908 	ret = 0;
3909 
3910 	while (!kthread_should_stop()) {
3911 		/*
3912 		 * Ensure that both TX and RX per connection kthreads
3913 		 * are scheduled to run on the same CPU.
3914 		 */
3915 		iscsit_thread_check_cpumask(conn, current, 1);
3916 
3917 		wait_event_interruptible(conn->queues_wq,
3918 					 !iscsit_conn_all_queues_empty(conn) ||
3919 					 ts->status == ISCSI_THREAD_SET_RESET);
3920 
3921 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3922 		     signal_pending(current))
3923 			goto transport_err;
3924 
3925 get_immediate:
3926 		ret = iscsit_handle_immediate_queue(conn);
3927 		if (ret < 0)
3928 			goto transport_err;
3929 
3930 		ret = iscsit_handle_response_queue(conn);
3931 		if (ret == 1)
3932 			goto get_immediate;
3933 		else if (ret == -EAGAIN)
3934 			goto restart;
3935 		else if (ret < 0)
3936 			goto transport_err;
3937 	}
3938 
3939 transport_err:
3940 	iscsit_take_action_for_connection_exit(conn);
3941 	goto restart;
3942 out:
3943 	return 0;
3944 }
3945 
3946 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3947 {
3948 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3949 	struct iscsi_cmd *cmd;
3950 	int ret = 0;
3951 
3952 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3953 	case ISCSI_OP_SCSI_CMD:
3954 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3955 		if (!cmd)
3956 			goto reject;
3957 
3958 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3959 		break;
3960 	case ISCSI_OP_SCSI_DATA_OUT:
3961 		ret = iscsit_handle_data_out(conn, buf);
3962 		break;
3963 	case ISCSI_OP_NOOP_OUT:
3964 		cmd = NULL;
3965 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3966 			cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3967 			if (!cmd)
3968 				goto reject;
3969 		}
3970 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3971 		break;
3972 	case ISCSI_OP_SCSI_TMFUNC:
3973 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3974 		if (!cmd)
3975 			goto reject;
3976 
3977 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3978 		break;
3979 	case ISCSI_OP_TEXT:
3980 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3981 		if (!cmd)
3982 			goto reject;
3983 
3984 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3985 		break;
3986 	case ISCSI_OP_LOGOUT:
3987 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3988 		if (!cmd)
3989 			goto reject;
3990 
3991 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3992 		if (ret > 0)
3993 			wait_for_completion_timeout(&conn->conn_logout_comp,
3994 					SECONDS_FOR_LOGOUT_COMP * HZ);
3995 		break;
3996 	case ISCSI_OP_SNACK:
3997 		ret = iscsit_handle_snack(conn, buf);
3998 		break;
3999 	default:
4000 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
4001 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
4002 			pr_err("Cannot recover from unknown"
4003 			" opcode while ERL=0, closing iSCSI connection.\n");
4004 			return -1;
4005 		}
4006 		if (!conn->conn_ops->OFMarker) {
4007 			pr_err("Unable to recover from unknown"
4008 			" opcode while OFMarker=No, closing iSCSI"
4009 				" connection.\n");
4010 			return -1;
4011 		}
4012 		if (iscsit_recover_from_unknown_opcode(conn) < 0) {
4013 			pr_err("Unable to recover from unknown"
4014 				" opcode, closing iSCSI connection.\n");
4015 			return -1;
4016 		}
4017 		break;
4018 	}
4019 
4020 	return ret;
4021 reject:
4022 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4023 }
4024 
4025 int iscsi_target_rx_thread(void *arg)
4026 {
4027 	int ret;
4028 	u8 buffer[ISCSI_HDR_LEN], opcode;
4029 	u32 checksum = 0, digest = 0;
4030 	struct iscsi_conn *conn = NULL;
4031 	struct iscsi_thread_set *ts = arg;
4032 	struct kvec iov;
4033 	/*
4034 	 * Allow ourselves to be interrupted by SIGINT so that a
4035 	 * connection recovery / failure event can be triggered externally.
4036 	 */
4037 	allow_signal(SIGINT);
4038 
4039 restart:
4040 	conn = iscsi_rx_thread_pre_handler(ts);
4041 	if (!conn)
4042 		goto out;
4043 
4044 	if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
4045 		struct completion comp;
4046 		int rc;
4047 
4048 		init_completion(&comp);
4049 		rc = wait_for_completion_interruptible(&comp);
4050 		if (rc < 0)
4051 			goto transport_err;
4052 
4053 		goto out;
4054 	}
4055 
4056 	while (!kthread_should_stop()) {
4057 		/*
4058 		 * Ensure that both TX and RX per connection kthreads
4059 		 * are scheduled to run on the same CPU.
4060 		 */
4061 		iscsit_thread_check_cpumask(conn, current, 0);
4062 
4063 		memset(buffer, 0, ISCSI_HDR_LEN);
4064 		memset(&iov, 0, sizeof(struct kvec));
4065 
4066 		iov.iov_base	= buffer;
4067 		iov.iov_len	= ISCSI_HDR_LEN;
4068 
4069 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4070 		if (ret != ISCSI_HDR_LEN) {
4071 			iscsit_rx_thread_wait_for_tcp(conn);
4072 			goto transport_err;
4073 		}
4074 
4075 		if (conn->conn_ops->HeaderDigest) {
4076 			iov.iov_base	= &digest;
4077 			iov.iov_len	= ISCSI_CRC_LEN;
4078 
4079 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4080 			if (ret != ISCSI_CRC_LEN) {
4081 				iscsit_rx_thread_wait_for_tcp(conn);
4082 				goto transport_err;
4083 			}
4084 
4085 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
4086 					buffer, ISCSI_HDR_LEN,
4087 					0, NULL, (u8 *)&checksum);
4088 
4089 			if (digest != checksum) {
4090 				pr_err("HeaderDigest CRC32C failed,"
4091 					" received 0x%08x, computed 0x%08x\n",
4092 					digest, checksum);
4093 				/*
4094 				 * Set the PDU to 0xff so it will intentionally
4095 				 * hit default in the switch below.
4096 				 */
4097 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4098 				atomic_long_inc(&conn->sess->conn_digest_errors);
4099 			} else {
4100 				pr_debug("Got HeaderDigest CRC32C"
4101 						" 0x%08x\n", checksum);
4102 			}
4103 		}
4104 
4105 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4106 			goto transport_err;
4107 
4108 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4109 
4110 		if (conn->sess->sess_ops->SessionType &&
4111 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4112 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4113 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4114 			" while in Discovery Session, rejecting.\n", opcode);
4115 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4116 					  buffer);
4117 			goto transport_err;
4118 		}
4119 
4120 		ret = iscsi_target_rx_opcode(conn, buffer);
4121 		if (ret < 0)
4122 			goto transport_err;
4123 	}
4124 
4125 transport_err:
4126 	if (!signal_pending(current))
4127 		atomic_set(&conn->transport_failed, 1);
4128 	iscsit_take_action_for_connection_exit(conn);
4129 	goto restart;
4130 out:
4131 	return 0;
4132 }
4133 
4134 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4135 {
4136 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4137 	struct iscsi_session *sess = conn->sess;
4138 	/*
4139 	 * We expect this function to only ever be called from either RX or TX
4140 	 * thread context via iscsit_close_connection() once the other context
4141 	 * has been reset -> returned sleeping pre-handler state.
4142 	 */
4143 	spin_lock_bh(&conn->cmd_lock);
4144 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
4145 
4146 		list_del(&cmd->i_conn_node);
4147 		spin_unlock_bh(&conn->cmd_lock);
4148 
4149 		iscsit_increment_maxcmdsn(cmd, sess);
4150 
4151 		iscsit_free_cmd(cmd, true);
4152 
4153 		spin_lock_bh(&conn->cmd_lock);
4154 	}
4155 	spin_unlock_bh(&conn->cmd_lock);
4156 }
4157 
4158 static void iscsit_stop_timers_for_cmds(
4159 	struct iscsi_conn *conn)
4160 {
4161 	struct iscsi_cmd *cmd;
4162 
4163 	spin_lock_bh(&conn->cmd_lock);
4164 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4165 		if (cmd->data_direction == DMA_TO_DEVICE)
4166 			iscsit_stop_dataout_timer(cmd);
4167 	}
4168 	spin_unlock_bh(&conn->cmd_lock);
4169 }
4170 
4171 int iscsit_close_connection(
4172 	struct iscsi_conn *conn)
4173 {
4174 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4175 	struct iscsi_session	*sess = conn->sess;
4176 
4177 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4178 		" %u\n", conn->cid, sess->sid);
4179 	/*
4180 	 * Always up conn_logout_comp just in case the RX Thread is sleeping
4181 	 * and the logout response never got sent because the connection
4182 	 * failed.
4183 	 */
4184 	complete(&conn->conn_logout_comp);
4185 
4186 	iscsi_release_thread_set(conn);
4187 
4188 	iscsit_stop_timers_for_cmds(conn);
4189 	iscsit_stop_nopin_response_timer(conn);
4190 	iscsit_stop_nopin_timer(conn);
4191 	iscsit_free_queue_reqs_for_conn(conn);
4192 
4193 	/*
4194 	 * During Connection recovery drop unacknowledged out of order
4195 	 * commands for this connection, and prepare the other commands
4196 	 * for realligence.
4197 	 *
4198 	 * During normal operation clear the out of order commands (but
4199 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4200 	 * struct iscsi_cmds.
4201 	 */
4202 	if (atomic_read(&conn->connection_recovery)) {
4203 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4204 		iscsit_prepare_cmds_for_realligance(conn);
4205 	} else {
4206 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4207 		iscsit_release_commands_from_conn(conn);
4208 	}
4209 
4210 	/*
4211 	 * Handle decrementing session or connection usage count if
4212 	 * a logout response was not able to be sent because the
4213 	 * connection failed.  Fall back to Session Recovery here.
4214 	 */
4215 	if (atomic_read(&conn->conn_logout_remove)) {
4216 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4217 			iscsit_dec_conn_usage_count(conn);
4218 			iscsit_dec_session_usage_count(sess);
4219 		}
4220 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4221 			iscsit_dec_conn_usage_count(conn);
4222 
4223 		atomic_set(&conn->conn_logout_remove, 0);
4224 		atomic_set(&sess->session_reinstatement, 0);
4225 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4226 	}
4227 
4228 	spin_lock_bh(&sess->conn_lock);
4229 	list_del(&conn->conn_list);
4230 
4231 	/*
4232 	 * Attempt to let the Initiator know this connection failed by
4233 	 * sending an Connection Dropped Async Message on another
4234 	 * active connection.
4235 	 */
4236 	if (atomic_read(&conn->connection_recovery))
4237 		iscsit_build_conn_drop_async_message(conn);
4238 
4239 	spin_unlock_bh(&sess->conn_lock);
4240 
4241 	/*
4242 	 * If connection reinstatement is being performed on this connection,
4243 	 * up the connection reinstatement semaphore that is being blocked on
4244 	 * in iscsit_cause_connection_reinstatement().
4245 	 */
4246 	spin_lock_bh(&conn->state_lock);
4247 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4248 		spin_unlock_bh(&conn->state_lock);
4249 		complete(&conn->conn_wait_comp);
4250 		wait_for_completion(&conn->conn_post_wait_comp);
4251 		spin_lock_bh(&conn->state_lock);
4252 	}
4253 
4254 	/*
4255 	 * If connection reinstatement is being performed on this connection
4256 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4257 	 * connection wait rcfr semaphore that is being blocked on
4258 	 * an iscsit_connection_reinstatement_rcfr().
4259 	 */
4260 	if (atomic_read(&conn->connection_wait_rcfr)) {
4261 		spin_unlock_bh(&conn->state_lock);
4262 		complete(&conn->conn_wait_rcfr_comp);
4263 		wait_for_completion(&conn->conn_post_wait_comp);
4264 		spin_lock_bh(&conn->state_lock);
4265 	}
4266 	atomic_set(&conn->connection_reinstatement, 1);
4267 	spin_unlock_bh(&conn->state_lock);
4268 
4269 	/*
4270 	 * If any other processes are accessing this connection pointer we
4271 	 * must wait until they have completed.
4272 	 */
4273 	iscsit_check_conn_usage_count(conn);
4274 
4275 	if (conn->conn_rx_hash.tfm)
4276 		crypto_free_hash(conn->conn_rx_hash.tfm);
4277 	if (conn->conn_tx_hash.tfm)
4278 		crypto_free_hash(conn->conn_tx_hash.tfm);
4279 
4280 	if (conn->conn_cpumask)
4281 		free_cpumask_var(conn->conn_cpumask);
4282 
4283 	kfree(conn->conn_ops);
4284 	conn->conn_ops = NULL;
4285 
4286 	if (conn->sock)
4287 		sock_release(conn->sock);
4288 
4289 	if (conn->conn_transport->iscsit_free_conn)
4290 		conn->conn_transport->iscsit_free_conn(conn);
4291 
4292 	iscsit_put_transport(conn->conn_transport);
4293 
4294 	conn->thread_set = NULL;
4295 
4296 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4297 	conn->conn_state = TARG_CONN_STATE_FREE;
4298 	kfree(conn);
4299 
4300 	spin_lock_bh(&sess->conn_lock);
4301 	atomic_dec(&sess->nconn);
4302 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4303 		" %s\n", atomic_read(&sess->nconn),
4304 		sess->sess_ops->InitiatorName);
4305 	/*
4306 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4307 	 * Session that they all fail.
4308 	 */
4309 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4310 	     !atomic_read(&sess->session_logout))
4311 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4312 
4313 	/*
4314 	 * If this was not the last connection in the session, and we are
4315 	 * performing session reinstatement or falling back to ERL=0, call
4316 	 * iscsit_stop_session() without sleeping to shutdown the other
4317 	 * active connections.
4318 	 */
4319 	if (atomic_read(&sess->nconn)) {
4320 		if (!atomic_read(&sess->session_reinstatement) &&
4321 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4322 			spin_unlock_bh(&sess->conn_lock);
4323 			return 0;
4324 		}
4325 		if (!atomic_read(&sess->session_stop_active)) {
4326 			atomic_set(&sess->session_stop_active, 1);
4327 			spin_unlock_bh(&sess->conn_lock);
4328 			iscsit_stop_session(sess, 0, 0);
4329 			return 0;
4330 		}
4331 		spin_unlock_bh(&sess->conn_lock);
4332 		return 0;
4333 	}
4334 
4335 	/*
4336 	 * If this was the last connection in the session and one of the
4337 	 * following is occurring:
4338 	 *
4339 	 * Session Reinstatement is not being performed, and are falling back
4340 	 * to ERL=0 call iscsit_close_session().
4341 	 *
4342 	 * Session Logout was requested.  iscsit_close_session() will be called
4343 	 * elsewhere.
4344 	 *
4345 	 * Session Continuation is not being performed, start the Time2Retain
4346 	 * handler and check if sleep_on_sess_wait_sem is active.
4347 	 */
4348 	if (!atomic_read(&sess->session_reinstatement) &&
4349 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4350 		spin_unlock_bh(&sess->conn_lock);
4351 		target_put_session(sess->se_sess);
4352 
4353 		return 0;
4354 	} else if (atomic_read(&sess->session_logout)) {
4355 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4356 		sess->session_state = TARG_SESS_STATE_FREE;
4357 		spin_unlock_bh(&sess->conn_lock);
4358 
4359 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4360 			complete(&sess->session_wait_comp);
4361 
4362 		return 0;
4363 	} else {
4364 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4365 		sess->session_state = TARG_SESS_STATE_FAILED;
4366 
4367 		if (!atomic_read(&sess->session_continuation)) {
4368 			spin_unlock_bh(&sess->conn_lock);
4369 			iscsit_start_time2retain_handler(sess);
4370 		} else
4371 			spin_unlock_bh(&sess->conn_lock);
4372 
4373 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4374 			complete(&sess->session_wait_comp);
4375 
4376 		return 0;
4377 	}
4378 	spin_unlock_bh(&sess->conn_lock);
4379 
4380 	return 0;
4381 }
4382 
4383 int iscsit_close_session(struct iscsi_session *sess)
4384 {
4385 	struct iscsi_portal_group *tpg = sess->tpg;
4386 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4387 
4388 	if (atomic_read(&sess->nconn)) {
4389 		pr_err("%d connection(s) still exist for iSCSI session"
4390 			" to %s\n", atomic_read(&sess->nconn),
4391 			sess->sess_ops->InitiatorName);
4392 		BUG();
4393 	}
4394 
4395 	spin_lock_bh(&se_tpg->session_lock);
4396 	atomic_set(&sess->session_logout, 1);
4397 	atomic_set(&sess->session_reinstatement, 1);
4398 	iscsit_stop_time2retain_timer(sess);
4399 	spin_unlock_bh(&se_tpg->session_lock);
4400 
4401 	/*
4402 	 * transport_deregister_session_configfs() will clear the
4403 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4404 	 * can be setting it again with __transport_register_session() in
4405 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4406 	 * completes in iscsi_np context.
4407 	 */
4408 	transport_deregister_session_configfs(sess->se_sess);
4409 
4410 	/*
4411 	 * If any other processes are accessing this session pointer we must
4412 	 * wait until they have completed.  If we are in an interrupt (the
4413 	 * time2retain handler) and contain and active session usage count we
4414 	 * restart the timer and exit.
4415 	 */
4416 	if (!in_interrupt()) {
4417 		if (iscsit_check_session_usage_count(sess) == 1)
4418 			iscsit_stop_session(sess, 1, 1);
4419 	} else {
4420 		if (iscsit_check_session_usage_count(sess) == 2) {
4421 			atomic_set(&sess->session_logout, 0);
4422 			iscsit_start_time2retain_handler(sess);
4423 			return 0;
4424 		}
4425 	}
4426 
4427 	transport_deregister_session(sess->se_sess);
4428 
4429 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4430 		iscsit_free_connection_recovery_entires(sess);
4431 
4432 	iscsit_free_all_ooo_cmdsns(sess);
4433 
4434 	spin_lock_bh(&se_tpg->session_lock);
4435 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4436 	sess->session_state = TARG_SESS_STATE_FREE;
4437 	pr_debug("Released iSCSI session from node: %s\n",
4438 			sess->sess_ops->InitiatorName);
4439 	tpg->nsessions--;
4440 	if (tpg->tpg_tiqn)
4441 		tpg->tpg_tiqn->tiqn_nsessions--;
4442 
4443 	pr_debug("Decremented number of active iSCSI Sessions on"
4444 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4445 
4446 	spin_lock(&sess_idr_lock);
4447 	idr_remove(&sess_idr, sess->session_index);
4448 	spin_unlock(&sess_idr_lock);
4449 
4450 	kfree(sess->sess_ops);
4451 	sess->sess_ops = NULL;
4452 	spin_unlock_bh(&se_tpg->session_lock);
4453 
4454 	kfree(sess);
4455 	return 0;
4456 }
4457 
4458 static void iscsit_logout_post_handler_closesession(
4459 	struct iscsi_conn *conn)
4460 {
4461 	struct iscsi_session *sess = conn->sess;
4462 
4463 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4464 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4465 
4466 	atomic_set(&conn->conn_logout_remove, 0);
4467 	complete(&conn->conn_logout_comp);
4468 
4469 	iscsit_dec_conn_usage_count(conn);
4470 	iscsit_stop_session(sess, 1, 1);
4471 	iscsit_dec_session_usage_count(sess);
4472 	target_put_session(sess->se_sess);
4473 }
4474 
4475 static void iscsit_logout_post_handler_samecid(
4476 	struct iscsi_conn *conn)
4477 {
4478 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4479 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4480 
4481 	atomic_set(&conn->conn_logout_remove, 0);
4482 	complete(&conn->conn_logout_comp);
4483 
4484 	iscsit_cause_connection_reinstatement(conn, 1);
4485 	iscsit_dec_conn_usage_count(conn);
4486 }
4487 
4488 static void iscsit_logout_post_handler_diffcid(
4489 	struct iscsi_conn *conn,
4490 	u16 cid)
4491 {
4492 	struct iscsi_conn *l_conn;
4493 	struct iscsi_session *sess = conn->sess;
4494 
4495 	if (!sess)
4496 		return;
4497 
4498 	spin_lock_bh(&sess->conn_lock);
4499 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4500 		if (l_conn->cid == cid) {
4501 			iscsit_inc_conn_usage_count(l_conn);
4502 			break;
4503 		}
4504 	}
4505 	spin_unlock_bh(&sess->conn_lock);
4506 
4507 	if (!l_conn)
4508 		return;
4509 
4510 	if (l_conn->sock)
4511 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4512 
4513 	spin_lock_bh(&l_conn->state_lock);
4514 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4515 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4516 	spin_unlock_bh(&l_conn->state_lock);
4517 
4518 	iscsit_cause_connection_reinstatement(l_conn, 1);
4519 	iscsit_dec_conn_usage_count(l_conn);
4520 }
4521 
4522 /*
4523  *	Return of 0 causes the TX thread to restart.
4524  */
4525 int iscsit_logout_post_handler(
4526 	struct iscsi_cmd *cmd,
4527 	struct iscsi_conn *conn)
4528 {
4529 	int ret = 0;
4530 
4531 	switch (cmd->logout_reason) {
4532 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4533 		switch (cmd->logout_response) {
4534 		case ISCSI_LOGOUT_SUCCESS:
4535 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4536 		default:
4537 			iscsit_logout_post_handler_closesession(conn);
4538 			break;
4539 		}
4540 		ret = 0;
4541 		break;
4542 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4543 		if (conn->cid == cmd->logout_cid) {
4544 			switch (cmd->logout_response) {
4545 			case ISCSI_LOGOUT_SUCCESS:
4546 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4547 			default:
4548 				iscsit_logout_post_handler_samecid(conn);
4549 				break;
4550 			}
4551 			ret = 0;
4552 		} else {
4553 			switch (cmd->logout_response) {
4554 			case ISCSI_LOGOUT_SUCCESS:
4555 				iscsit_logout_post_handler_diffcid(conn,
4556 					cmd->logout_cid);
4557 				break;
4558 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4559 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4560 			default:
4561 				break;
4562 			}
4563 			ret = 1;
4564 		}
4565 		break;
4566 	case ISCSI_LOGOUT_REASON_RECOVERY:
4567 		switch (cmd->logout_response) {
4568 		case ISCSI_LOGOUT_SUCCESS:
4569 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4570 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4571 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4572 		default:
4573 			break;
4574 		}
4575 		ret = 1;
4576 		break;
4577 	default:
4578 		break;
4579 
4580 	}
4581 	return ret;
4582 }
4583 EXPORT_SYMBOL(iscsit_logout_post_handler);
4584 
4585 void iscsit_fail_session(struct iscsi_session *sess)
4586 {
4587 	struct iscsi_conn *conn;
4588 
4589 	spin_lock_bh(&sess->conn_lock);
4590 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4591 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4592 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4593 	}
4594 	spin_unlock_bh(&sess->conn_lock);
4595 
4596 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4597 	sess->session_state = TARG_SESS_STATE_FAILED;
4598 }
4599 
4600 int iscsit_free_session(struct iscsi_session *sess)
4601 {
4602 	u16 conn_count = atomic_read(&sess->nconn);
4603 	struct iscsi_conn *conn, *conn_tmp = NULL;
4604 	int is_last;
4605 
4606 	spin_lock_bh(&sess->conn_lock);
4607 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4608 
4609 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4610 			conn_list) {
4611 		if (conn_count == 0)
4612 			break;
4613 
4614 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4615 			is_last = 1;
4616 		} else {
4617 			iscsit_inc_conn_usage_count(conn_tmp);
4618 			is_last = 0;
4619 		}
4620 		iscsit_inc_conn_usage_count(conn);
4621 
4622 		spin_unlock_bh(&sess->conn_lock);
4623 		iscsit_cause_connection_reinstatement(conn, 1);
4624 		spin_lock_bh(&sess->conn_lock);
4625 
4626 		iscsit_dec_conn_usage_count(conn);
4627 		if (is_last == 0)
4628 			iscsit_dec_conn_usage_count(conn_tmp);
4629 
4630 		conn_count--;
4631 	}
4632 
4633 	if (atomic_read(&sess->nconn)) {
4634 		spin_unlock_bh(&sess->conn_lock);
4635 		wait_for_completion(&sess->session_wait_comp);
4636 	} else
4637 		spin_unlock_bh(&sess->conn_lock);
4638 
4639 	target_put_session(sess->se_sess);
4640 	return 0;
4641 }
4642 
4643 void iscsit_stop_session(
4644 	struct iscsi_session *sess,
4645 	int session_sleep,
4646 	int connection_sleep)
4647 {
4648 	u16 conn_count = atomic_read(&sess->nconn);
4649 	struct iscsi_conn *conn, *conn_tmp = NULL;
4650 	int is_last;
4651 
4652 	spin_lock_bh(&sess->conn_lock);
4653 	if (session_sleep)
4654 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4655 
4656 	if (connection_sleep) {
4657 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4658 				conn_list) {
4659 			if (conn_count == 0)
4660 				break;
4661 
4662 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4663 				is_last = 1;
4664 			} else {
4665 				iscsit_inc_conn_usage_count(conn_tmp);
4666 				is_last = 0;
4667 			}
4668 			iscsit_inc_conn_usage_count(conn);
4669 
4670 			spin_unlock_bh(&sess->conn_lock);
4671 			iscsit_cause_connection_reinstatement(conn, 1);
4672 			spin_lock_bh(&sess->conn_lock);
4673 
4674 			iscsit_dec_conn_usage_count(conn);
4675 			if (is_last == 0)
4676 				iscsit_dec_conn_usage_count(conn_tmp);
4677 			conn_count--;
4678 		}
4679 	} else {
4680 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4681 			iscsit_cause_connection_reinstatement(conn, 0);
4682 	}
4683 
4684 	if (session_sleep && atomic_read(&sess->nconn)) {
4685 		spin_unlock_bh(&sess->conn_lock);
4686 		wait_for_completion(&sess->session_wait_comp);
4687 	} else
4688 		spin_unlock_bh(&sess->conn_lock);
4689 }
4690 
4691 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4692 {
4693 	struct iscsi_session *sess;
4694 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4695 	struct se_session *se_sess, *se_sess_tmp;
4696 	int session_count = 0;
4697 
4698 	spin_lock_bh(&se_tpg->session_lock);
4699 	if (tpg->nsessions && !force) {
4700 		spin_unlock_bh(&se_tpg->session_lock);
4701 		return -1;
4702 	}
4703 
4704 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4705 			sess_list) {
4706 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4707 
4708 		spin_lock(&sess->conn_lock);
4709 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4710 		    atomic_read(&sess->session_logout) ||
4711 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4712 			spin_unlock(&sess->conn_lock);
4713 			continue;
4714 		}
4715 		atomic_set(&sess->session_reinstatement, 1);
4716 		spin_unlock(&sess->conn_lock);
4717 		spin_unlock_bh(&se_tpg->session_lock);
4718 
4719 		iscsit_free_session(sess);
4720 		spin_lock_bh(&se_tpg->session_lock);
4721 
4722 		session_count++;
4723 	}
4724 	spin_unlock_bh(&se_tpg->session_lock);
4725 
4726 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4727 			" Group: %hu\n", session_count, tpg->tpgt);
4728 	return 0;
4729 }
4730 
4731 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4732 MODULE_VERSION("4.1.x");
4733 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4734 MODULE_LICENSE("GPL");
4735 
4736 module_init(iscsi_target_init_module);
4737 module_exit(iscsi_target_cleanup_module);
4738