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 	}
469 
470 	np->np_transport->iscsit_free_np(np);
471 
472 	spin_lock_bh(&np_lock);
473 	list_del(&np->np_list);
474 	spin_unlock_bh(&np_lock);
475 
476 	pr_debug("CORE[0] - Removed Network Portal: %s:%hu on %s\n",
477 		np->np_ip, np->np_port, np->np_transport->name);
478 
479 	iscsit_put_transport(np->np_transport);
480 	kfree(np);
481 	return 0;
482 }
483 
484 static int iscsit_immediate_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
485 static int iscsit_response_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
486 
487 static int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
488 {
489 	iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
490 	return 0;
491 }
492 
493 static struct iscsit_transport iscsi_target_transport = {
494 	.name			= "iSCSI/TCP",
495 	.transport_type		= ISCSI_TCP,
496 	.owner			= NULL,
497 	.iscsit_setup_np	= iscsit_setup_np,
498 	.iscsit_accept_np	= iscsit_accept_np,
499 	.iscsit_free_np		= iscsit_free_np,
500 	.iscsit_get_login_rx	= iscsit_get_login_rx,
501 	.iscsit_put_login_tx	= iscsit_put_login_tx,
502 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
503 	.iscsit_immediate_queue	= iscsit_immediate_queue,
504 	.iscsit_response_queue	= iscsit_response_queue,
505 	.iscsit_queue_data_in	= iscsit_queue_rsp,
506 	.iscsit_queue_status	= iscsit_queue_rsp,
507 };
508 
509 static int __init iscsi_target_init_module(void)
510 {
511 	int ret = 0;
512 
513 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
514 
515 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
516 	if (!iscsit_global) {
517 		pr_err("Unable to allocate memory for iscsit_global\n");
518 		return -1;
519 	}
520 	mutex_init(&auth_id_lock);
521 	spin_lock_init(&sess_idr_lock);
522 	idr_init(&tiqn_idr);
523 	idr_init(&sess_idr);
524 
525 	ret = iscsi_target_register_configfs();
526 	if (ret < 0)
527 		goto out;
528 
529 	ret = iscsi_thread_set_init();
530 	if (ret < 0)
531 		goto configfs_out;
532 
533 	if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
534 			TARGET_THREAD_SET_COUNT) {
535 		pr_err("iscsi_allocate_thread_sets() returned"
536 			" unexpected value!\n");
537 		goto ts_out1;
538 	}
539 
540 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
541 			sizeof(struct iscsi_queue_req),
542 			__alignof__(struct iscsi_queue_req), 0, NULL);
543 	if (!lio_qr_cache) {
544 		pr_err("nable to kmem_cache_create() for"
545 				" lio_qr_cache\n");
546 		goto ts_out2;
547 	}
548 
549 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
550 			sizeof(struct iscsi_datain_req),
551 			__alignof__(struct iscsi_datain_req), 0, NULL);
552 	if (!lio_dr_cache) {
553 		pr_err("Unable to kmem_cache_create() for"
554 				" lio_dr_cache\n");
555 		goto qr_out;
556 	}
557 
558 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
559 			sizeof(struct iscsi_ooo_cmdsn),
560 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
561 	if (!lio_ooo_cache) {
562 		pr_err("Unable to kmem_cache_create() for"
563 				" lio_ooo_cache\n");
564 		goto dr_out;
565 	}
566 
567 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
568 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
569 			0, NULL);
570 	if (!lio_r2t_cache) {
571 		pr_err("Unable to kmem_cache_create() for"
572 				" lio_r2t_cache\n");
573 		goto ooo_out;
574 	}
575 
576 	iscsit_register_transport(&iscsi_target_transport);
577 
578 	if (iscsit_load_discovery_tpg() < 0)
579 		goto r2t_out;
580 
581 	return ret;
582 r2t_out:
583 	kmem_cache_destroy(lio_r2t_cache);
584 ooo_out:
585 	kmem_cache_destroy(lio_ooo_cache);
586 dr_out:
587 	kmem_cache_destroy(lio_dr_cache);
588 qr_out:
589 	kmem_cache_destroy(lio_qr_cache);
590 ts_out2:
591 	iscsi_deallocate_thread_sets();
592 ts_out1:
593 	iscsi_thread_set_free();
594 configfs_out:
595 	iscsi_target_deregister_configfs();
596 out:
597 	kfree(iscsit_global);
598 	return -ENOMEM;
599 }
600 
601 static void __exit iscsi_target_cleanup_module(void)
602 {
603 	iscsi_deallocate_thread_sets();
604 	iscsi_thread_set_free();
605 	iscsit_release_discovery_tpg();
606 	iscsit_unregister_transport(&iscsi_target_transport);
607 	kmem_cache_destroy(lio_qr_cache);
608 	kmem_cache_destroy(lio_dr_cache);
609 	kmem_cache_destroy(lio_ooo_cache);
610 	kmem_cache_destroy(lio_r2t_cache);
611 
612 	iscsi_target_deregister_configfs();
613 
614 	kfree(iscsit_global);
615 }
616 
617 static int iscsit_add_reject(
618 	struct iscsi_conn *conn,
619 	u8 reason,
620 	unsigned char *buf)
621 {
622 	struct iscsi_cmd *cmd;
623 
624 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
625 	if (!cmd)
626 		return -1;
627 
628 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
629 	cmd->reject_reason = reason;
630 
631 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
632 	if (!cmd->buf_ptr) {
633 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
634 		iscsit_free_cmd(cmd, false);
635 		return -1;
636 	}
637 
638 	spin_lock_bh(&conn->cmd_lock);
639 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
640 	spin_unlock_bh(&conn->cmd_lock);
641 
642 	cmd->i_state = ISTATE_SEND_REJECT;
643 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
644 
645 	return -1;
646 }
647 
648 static int iscsit_add_reject_from_cmd(
649 	struct iscsi_cmd *cmd,
650 	u8 reason,
651 	bool add_to_conn,
652 	unsigned char *buf)
653 {
654 	struct iscsi_conn *conn;
655 
656 	if (!cmd->conn) {
657 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
658 				cmd->init_task_tag);
659 		return -1;
660 	}
661 	conn = cmd->conn;
662 
663 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
664 	cmd->reject_reason = reason;
665 
666 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
667 	if (!cmd->buf_ptr) {
668 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
669 		iscsit_free_cmd(cmd, false);
670 		return -1;
671 	}
672 
673 	if (add_to_conn) {
674 		spin_lock_bh(&conn->cmd_lock);
675 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
676 		spin_unlock_bh(&conn->cmd_lock);
677 	}
678 
679 	cmd->i_state = ISTATE_SEND_REJECT;
680 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
681 	/*
682 	 * Perform the kref_put now if se_cmd has already been setup by
683 	 * scsit_setup_scsi_cmd()
684 	 */
685 	if (cmd->se_cmd.se_tfo != NULL) {
686 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
687 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
688 	}
689 	return -1;
690 }
691 
692 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
693 				 unsigned char *buf)
694 {
695 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
696 }
697 
698 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
699 {
700 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
701 }
702 
703 /*
704  * Map some portion of the allocated scatterlist to an iovec, suitable for
705  * kernel sockets to copy data in/out.
706  */
707 static int iscsit_map_iovec(
708 	struct iscsi_cmd *cmd,
709 	struct kvec *iov,
710 	u32 data_offset,
711 	u32 data_length)
712 {
713 	u32 i = 0;
714 	struct scatterlist *sg;
715 	unsigned int page_off;
716 
717 	/*
718 	 * We know each entry in t_data_sg contains a page.
719 	 */
720 	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
721 	page_off = (data_offset % PAGE_SIZE);
722 
723 	cmd->first_data_sg = sg;
724 	cmd->first_data_sg_off = page_off;
725 
726 	while (data_length) {
727 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
728 
729 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
730 		iov[i].iov_len = cur_len;
731 
732 		data_length -= cur_len;
733 		page_off = 0;
734 		sg = sg_next(sg);
735 		i++;
736 	}
737 
738 	cmd->kmapped_nents = i;
739 
740 	return i;
741 }
742 
743 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
744 {
745 	u32 i;
746 	struct scatterlist *sg;
747 
748 	sg = cmd->first_data_sg;
749 
750 	for (i = 0; i < cmd->kmapped_nents; i++)
751 		kunmap(sg_page(&sg[i]));
752 }
753 
754 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
755 {
756 	struct iscsi_cmd *cmd;
757 
758 	conn->exp_statsn = exp_statsn;
759 
760 	if (conn->sess->sess_ops->RDMAExtensions)
761 		return;
762 
763 	spin_lock_bh(&conn->cmd_lock);
764 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
765 		spin_lock(&cmd->istate_lock);
766 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
767 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
768 			cmd->i_state = ISTATE_REMOVE;
769 			spin_unlock(&cmd->istate_lock);
770 			iscsit_add_cmd_to_immediate_queue(cmd, conn,
771 						cmd->i_state);
772 			continue;
773 		}
774 		spin_unlock(&cmd->istate_lock);
775 	}
776 	spin_unlock_bh(&conn->cmd_lock);
777 }
778 
779 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
780 {
781 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
782 
783 	iov_count += ISCSI_IOV_DATA_BUFFER;
784 
785 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
786 	if (!cmd->iov_data) {
787 		pr_err("Unable to allocate cmd->iov_data\n");
788 		return -ENOMEM;
789 	}
790 
791 	cmd->orig_iov_data_count = iov_count;
792 	return 0;
793 }
794 
795 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
796 			  unsigned char *buf)
797 {
798 	int data_direction, payload_length;
799 	struct iscsi_scsi_req *hdr;
800 	int iscsi_task_attr;
801 	int sam_task_attr;
802 
803 	spin_lock_bh(&conn->sess->session_stats_lock);
804 	conn->sess->cmd_pdus++;
805 	if (conn->sess->se_sess->se_node_acl) {
806 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
807 		conn->sess->se_sess->se_node_acl->num_cmds++;
808 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
809 	}
810 	spin_unlock_bh(&conn->sess->session_stats_lock);
811 
812 	hdr			= (struct iscsi_scsi_req *) buf;
813 	payload_length		= ntoh24(hdr->dlength);
814 
815 	/* FIXME; Add checks for AdditionalHeaderSegment */
816 
817 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
818 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
819 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
820 				" not set. Bad iSCSI Initiator.\n");
821 		return iscsit_add_reject_cmd(cmd,
822 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
823 	}
824 
825 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
826 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
827 		/*
828 		 * Vmware ESX v3.0 uses a modified Cisco Initiator (v3.4.2)
829 		 * that adds support for RESERVE/RELEASE.  There is a bug
830 		 * add with this new functionality that sets R/W bits when
831 		 * neither CDB carries any READ or WRITE datapayloads.
832 		 */
833 		if ((hdr->cdb[0] == 0x16) || (hdr->cdb[0] == 0x17)) {
834 			hdr->flags &= ~ISCSI_FLAG_CMD_READ;
835 			hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
836 			goto done;
837 		}
838 
839 		pr_err("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
840 			" set when Expected Data Transfer Length is 0 for"
841 			" CDB: 0x%02x. Bad iSCSI Initiator.\n", hdr->cdb[0]);
842 		return iscsit_add_reject_cmd(cmd,
843 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
844 	}
845 done:
846 
847 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
848 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
849 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
850 			" MUST be set if Expected Data Transfer Length is not 0."
851 			" Bad iSCSI Initiator\n");
852 		return iscsit_add_reject_cmd(cmd,
853 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
854 	}
855 
856 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
857 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
858 		pr_err("Bidirectional operations not supported!\n");
859 		return iscsit_add_reject_cmd(cmd,
860 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
861 	}
862 
863 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
864 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
865 				" Scsi Command PDU.\n");
866 		return iscsit_add_reject_cmd(cmd,
867 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
868 	}
869 
870 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
871 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
872 			" protocol error.\n", payload_length);
873 		return iscsit_add_reject_cmd(cmd,
874 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
875 	}
876 
877 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
878 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
879 		pr_err("Expected Data Transfer Length and Length of"
880 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
881 			" bit is not set protocol error\n");
882 		return iscsit_add_reject_cmd(cmd,
883 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
884 	}
885 
886 	if (payload_length > be32_to_cpu(hdr->data_length)) {
887 		pr_err("DataSegmentLength: %u is greater than"
888 			" EDTL: %u, protocol error.\n", payload_length,
889 				hdr->data_length);
890 		return iscsit_add_reject_cmd(cmd,
891 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
892 	}
893 
894 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
895 		pr_err("DataSegmentLength: %u is greater than"
896 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
897 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
898 		return iscsit_add_reject_cmd(cmd,
899 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
900 	}
901 
902 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
903 		pr_err("DataSegmentLength: %u is greater than"
904 			" FirstBurstLength: %u, protocol error.\n",
905 			payload_length, conn->sess->sess_ops->FirstBurstLength);
906 		return iscsit_add_reject_cmd(cmd,
907 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
908 	}
909 
910 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
911 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
912 			  DMA_NONE;
913 
914 	cmd->data_direction = data_direction;
915 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
916 	/*
917 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
918 	 */
919 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
920 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
921 		sam_task_attr = MSG_SIMPLE_TAG;
922 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
923 		sam_task_attr = MSG_ORDERED_TAG;
924 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
925 		sam_task_attr = MSG_HEAD_TAG;
926 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
927 		sam_task_attr = MSG_ACA_TAG;
928 	else {
929 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
930 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
931 		sam_task_attr = MSG_SIMPLE_TAG;
932 	}
933 
934 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
935 	cmd->i_state		= ISTATE_NEW_CMD;
936 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
937 	cmd->immediate_data	= (payload_length) ? 1 : 0;
938 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
939 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
940 	if (cmd->unsolicited_data)
941 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
942 
943 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
944 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
945 		spin_lock_bh(&conn->sess->ttt_lock);
946 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
947 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
948 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
949 		spin_unlock_bh(&conn->sess->ttt_lock);
950 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
951 		cmd->targ_xfer_tag = 0xFFFFFFFF;
952 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
953 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
954 	cmd->first_burst_len	= payload_length;
955 
956 	if (!conn->sess->sess_ops->RDMAExtensions &&
957 	     cmd->data_direction == DMA_FROM_DEVICE) {
958 		struct iscsi_datain_req *dr;
959 
960 		dr = iscsit_allocate_datain_req();
961 		if (!dr)
962 			return iscsit_add_reject_cmd(cmd,
963 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
964 
965 		iscsit_attach_datain_req(cmd, dr);
966 	}
967 
968 	/*
969 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
970 	 */
971 	transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
972 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
973 			cmd->data_direction, sam_task_attr,
974 			cmd->sense_buffer + 2);
975 
976 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
977 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
978 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
979 		conn->cid);
980 
981 	target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
982 
983 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
984 						     scsilun_to_int(&hdr->lun));
985 	if (cmd->sense_reason)
986 		goto attach_cmd;
987 
988 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
989 	if (cmd->sense_reason) {
990 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
991 			return iscsit_add_reject_cmd(cmd,
992 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
993 		}
994 
995 		goto attach_cmd;
996 	}
997 
998 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
999 		return iscsit_add_reject_cmd(cmd,
1000 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1001 	}
1002 
1003 attach_cmd:
1004 	spin_lock_bh(&conn->cmd_lock);
1005 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1006 	spin_unlock_bh(&conn->cmd_lock);
1007 	/*
1008 	 * Check if we need to delay processing because of ALUA
1009 	 * Active/NonOptimized primary access state..
1010 	 */
1011 	core_alua_check_nonop_delay(&cmd->se_cmd);
1012 
1013 	return 0;
1014 }
1015 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1016 
1017 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1018 {
1019 	iscsit_set_dataout_sequence_values(cmd);
1020 
1021 	spin_lock_bh(&cmd->dataout_timeout_lock);
1022 	iscsit_start_dataout_timer(cmd, cmd->conn);
1023 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1024 }
1025 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1026 
1027 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1028 			    struct iscsi_scsi_req *hdr)
1029 {
1030 	int cmdsn_ret = 0;
1031 	/*
1032 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1033 	 * the Immediate Bit is not set, and no Immediate
1034 	 * Data is attached.
1035 	 *
1036 	 * A PDU/CmdSN carrying Immediate Data can only
1037 	 * be processed after the DataCRC has passed.
1038 	 * If the DataCRC fails, the CmdSN MUST NOT
1039 	 * be acknowledged. (See below)
1040 	 */
1041 	if (!cmd->immediate_data) {
1042 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1043 					(unsigned char *)hdr, hdr->cmdsn);
1044 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1045 			return -1;
1046 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1047 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1048 			return 0;
1049 		}
1050 	}
1051 
1052 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1053 
1054 	/*
1055 	 * If no Immediate Data is attached, it's OK to return now.
1056 	 */
1057 	if (!cmd->immediate_data) {
1058 		if (!cmd->sense_reason && cmd->unsolicited_data)
1059 			iscsit_set_unsoliticed_dataout(cmd);
1060 		if (!cmd->sense_reason)
1061 			return 0;
1062 
1063 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1064 		return 0;
1065 	}
1066 
1067 	/*
1068 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1069 	 * execution.  These exceptions are processed in CmdSN order using
1070 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1071 	 */
1072 	if (cmd->sense_reason) {
1073 		if (cmd->reject_reason)
1074 			return 0;
1075 
1076 		return 1;
1077 	}
1078 	/*
1079 	 * Call directly into transport_generic_new_cmd() to perform
1080 	 * the backend memory allocation.
1081 	 */
1082 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1083 	if (cmd->sense_reason)
1084 		return 1;
1085 
1086 	return 0;
1087 }
1088 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1089 
1090 static int
1091 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1092 			  bool dump_payload)
1093 {
1094 	struct iscsi_conn *conn = cmd->conn;
1095 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1096 	/*
1097 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1098 	 */
1099 	if (dump_payload == true)
1100 		goto after_immediate_data;
1101 
1102 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1103 					cmd->first_burst_len);
1104 after_immediate_data:
1105 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1106 		/*
1107 		 * A PDU/CmdSN carrying Immediate Data passed
1108 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1109 		 * Immediate Bit is not set.
1110 		 */
1111 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1112 					(unsigned char *)hdr, hdr->cmdsn);
1113 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1114 			return -1;
1115 
1116 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1117 			int rc;
1118 
1119 			rc = iscsit_dump_data_payload(cmd->conn,
1120 						      cmd->first_burst_len, 1);
1121 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1122 			return rc;
1123 		} else if (cmd->unsolicited_data)
1124 			iscsit_set_unsoliticed_dataout(cmd);
1125 
1126 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1127 		/*
1128 		 * Immediate Data failed DataCRC and ERL>=1,
1129 		 * silently drop this PDU and let the initiator
1130 		 * plug the CmdSN gap.
1131 		 *
1132 		 * FIXME: Send Unsolicited NOPIN with reserved
1133 		 * TTT here to help the initiator figure out
1134 		 * the missing CmdSN, although they should be
1135 		 * intelligent enough to determine the missing
1136 		 * CmdSN and issue a retry to plug the sequence.
1137 		 */
1138 		cmd->i_state = ISTATE_REMOVE;
1139 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1140 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1141 		return -1;
1142 
1143 	return 0;
1144 }
1145 
1146 static int
1147 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1148 			   unsigned char *buf)
1149 {
1150 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1151 	int rc, immed_data;
1152 	bool dump_payload = false;
1153 
1154 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1155 	if (rc < 0)
1156 		return 0;
1157 	/*
1158 	 * Allocation iovecs needed for struct socket operations for
1159 	 * traditional iSCSI block I/O.
1160 	 */
1161 	if (iscsit_allocate_iovecs(cmd) < 0) {
1162 		return iscsit_add_reject_cmd(cmd,
1163 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1164 	}
1165 	immed_data = cmd->immediate_data;
1166 
1167 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1168 	if (rc < 0)
1169 		return rc;
1170 	else if (rc > 0)
1171 		dump_payload = true;
1172 
1173 	if (!immed_data)
1174 		return 0;
1175 
1176 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1177 }
1178 
1179 static u32 iscsit_do_crypto_hash_sg(
1180 	struct hash_desc *hash,
1181 	struct iscsi_cmd *cmd,
1182 	u32 data_offset,
1183 	u32 data_length,
1184 	u32 padding,
1185 	u8 *pad_bytes)
1186 {
1187 	u32 data_crc;
1188 	u32 i;
1189 	struct scatterlist *sg;
1190 	unsigned int page_off;
1191 
1192 	crypto_hash_init(hash);
1193 
1194 	sg = cmd->first_data_sg;
1195 	page_off = cmd->first_data_sg_off;
1196 
1197 	i = 0;
1198 	while (data_length) {
1199 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1200 
1201 		crypto_hash_update(hash, &sg[i], cur_len);
1202 
1203 		data_length -= cur_len;
1204 		page_off = 0;
1205 		i++;
1206 	}
1207 
1208 	if (padding) {
1209 		struct scatterlist pad_sg;
1210 
1211 		sg_init_one(&pad_sg, pad_bytes, padding);
1212 		crypto_hash_update(hash, &pad_sg, padding);
1213 	}
1214 	crypto_hash_final(hash, (u8 *) &data_crc);
1215 
1216 	return data_crc;
1217 }
1218 
1219 static void iscsit_do_crypto_hash_buf(
1220 	struct hash_desc *hash,
1221 	const void *buf,
1222 	u32 payload_length,
1223 	u32 padding,
1224 	u8 *pad_bytes,
1225 	u8 *data_crc)
1226 {
1227 	struct scatterlist sg;
1228 
1229 	crypto_hash_init(hash);
1230 
1231 	sg_init_one(&sg, buf, payload_length);
1232 	crypto_hash_update(hash, &sg, payload_length);
1233 
1234 	if (padding) {
1235 		sg_init_one(&sg, pad_bytes, padding);
1236 		crypto_hash_update(hash, &sg, padding);
1237 	}
1238 	crypto_hash_final(hash, data_crc);
1239 }
1240 
1241 int
1242 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1243 			  struct iscsi_cmd **out_cmd)
1244 {
1245 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1246 	struct iscsi_cmd *cmd = NULL;
1247 	struct se_cmd *se_cmd;
1248 	u32 payload_length = ntoh24(hdr->dlength);
1249 	int rc;
1250 
1251 	if (!payload_length) {
1252 		pr_err("DataOUT payload is ZERO, protocol error.\n");
1253 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1254 					 buf);
1255 	}
1256 
1257 	/* iSCSI write */
1258 	spin_lock_bh(&conn->sess->session_stats_lock);
1259 	conn->sess->rx_data_octets += payload_length;
1260 	if (conn->sess->se_sess->se_node_acl) {
1261 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
1262 		conn->sess->se_sess->se_node_acl->write_bytes += payload_length;
1263 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
1264 	}
1265 	spin_unlock_bh(&conn->sess->session_stats_lock);
1266 
1267 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1268 		pr_err("DataSegmentLength: %u is greater than"
1269 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1270 			conn->conn_ops->MaxXmitDataSegmentLength);
1271 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1272 					 buf);
1273 	}
1274 
1275 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1276 			payload_length);
1277 	if (!cmd)
1278 		return 0;
1279 
1280 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1281 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1282 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1283 		payload_length, conn->cid);
1284 
1285 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1286 		pr_err("Command ITT: 0x%08x received DataOUT after"
1287 			" last DataOUT received, dumping payload\n",
1288 			cmd->init_task_tag);
1289 		return iscsit_dump_data_payload(conn, payload_length, 1);
1290 	}
1291 
1292 	if (cmd->data_direction != DMA_TO_DEVICE) {
1293 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1294 			" NON-WRITE command.\n", cmd->init_task_tag);
1295 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
1296 	}
1297 	se_cmd = &cmd->se_cmd;
1298 	iscsit_mod_dataout_timer(cmd);
1299 
1300 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1301 		pr_err("DataOut Offset: %u, Length %u greater than"
1302 			" iSCSI Command EDTL %u, protocol error.\n",
1303 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1304 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1305 	}
1306 
1307 	if (cmd->unsolicited_data) {
1308 		int dump_unsolicited_data = 0;
1309 
1310 		if (conn->sess->sess_ops->InitialR2T) {
1311 			pr_err("Received unexpected unsolicited data"
1312 				" while InitialR2T=Yes, protocol error.\n");
1313 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1314 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1315 			return -1;
1316 		}
1317 		/*
1318 		 * Special case for dealing with Unsolicited DataOUT
1319 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1320 		 * failures;
1321 		 */
1322 
1323 		/* Something's amiss if we're not in WRITE_PENDING state... */
1324 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1325 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1326 			dump_unsolicited_data = 1;
1327 
1328 		if (dump_unsolicited_data) {
1329 			/*
1330 			 * Check if a delayed TASK_ABORTED status needs to
1331 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1332 			 * received with the unsolicitied data out.
1333 			 */
1334 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1335 				iscsit_stop_dataout_timer(cmd);
1336 
1337 			transport_check_aborted_status(se_cmd,
1338 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1339 			return iscsit_dump_data_payload(conn, payload_length, 1);
1340 		}
1341 	} else {
1342 		/*
1343 		 * For the normal solicited data path:
1344 		 *
1345 		 * Check for a delayed TASK_ABORTED status and dump any
1346 		 * incoming data out payload if one exists.  Also, when the
1347 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1348 		 * data out sequence, we decrement outstanding_r2ts.  Once
1349 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1350 		 * TASK_ABORTED status.
1351 		 */
1352 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1353 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1354 				if (--cmd->outstanding_r2ts < 1) {
1355 					iscsit_stop_dataout_timer(cmd);
1356 					transport_check_aborted_status(
1357 							se_cmd, 1);
1358 				}
1359 
1360 			return iscsit_dump_data_payload(conn, payload_length, 1);
1361 		}
1362 	}
1363 	/*
1364 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1365 	 * within-command recovery checks before receiving the payload.
1366 	 */
1367 	rc = iscsit_check_pre_dataout(cmd, buf);
1368 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1369 		return 0;
1370 	else if (rc == DATAOUT_CANNOT_RECOVER)
1371 		return -1;
1372 
1373 	*out_cmd = cmd;
1374 	return 0;
1375 }
1376 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1377 
1378 static int
1379 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1380 		   struct iscsi_data *hdr)
1381 {
1382 	struct kvec *iov;
1383 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1384 	u32 payload_length = ntoh24(hdr->dlength);
1385 	int iov_ret, data_crc_failed = 0;
1386 
1387 	rx_size += payload_length;
1388 	iov = &cmd->iov_data[0];
1389 
1390 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1391 				   payload_length);
1392 	if (iov_ret < 0)
1393 		return -1;
1394 
1395 	iov_count += iov_ret;
1396 
1397 	padding = ((-payload_length) & 3);
1398 	if (padding != 0) {
1399 		iov[iov_count].iov_base	= cmd->pad_bytes;
1400 		iov[iov_count++].iov_len = padding;
1401 		rx_size += padding;
1402 		pr_debug("Receiving %u padding bytes.\n", padding);
1403 	}
1404 
1405 	if (conn->conn_ops->DataDigest) {
1406 		iov[iov_count].iov_base = &checksum;
1407 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1408 		rx_size += ISCSI_CRC_LEN;
1409 	}
1410 
1411 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1412 
1413 	iscsit_unmap_iovec(cmd);
1414 
1415 	if (rx_got != rx_size)
1416 		return -1;
1417 
1418 	if (conn->conn_ops->DataDigest) {
1419 		u32 data_crc;
1420 
1421 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1422 						    be32_to_cpu(hdr->offset),
1423 						    payload_length, padding,
1424 						    cmd->pad_bytes);
1425 
1426 		if (checksum != data_crc) {
1427 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1428 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1429 				" does not match computed 0x%08x\n",
1430 				hdr->itt, hdr->offset, payload_length,
1431 				hdr->datasn, checksum, data_crc);
1432 			data_crc_failed = 1;
1433 		} else {
1434 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1435 				" %u bytes of Data Out\n", checksum,
1436 				payload_length);
1437 		}
1438 	}
1439 
1440 	return data_crc_failed;
1441 }
1442 
1443 int
1444 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1445 			     bool data_crc_failed)
1446 {
1447 	struct iscsi_conn *conn = cmd->conn;
1448 	int rc, ooo_cmdsn;
1449 	/*
1450 	 * Increment post receive data and CRC values or perform
1451 	 * within-command recovery.
1452 	 */
1453 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1454 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1455 		return 0;
1456 	else if (rc == DATAOUT_SEND_R2T) {
1457 		iscsit_set_dataout_sequence_values(cmd);
1458 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1459 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1460 		/*
1461 		 * Handle extra special case for out of order
1462 		 * Unsolicited Data Out.
1463 		 */
1464 		spin_lock_bh(&cmd->istate_lock);
1465 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1466 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1467 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1468 		spin_unlock_bh(&cmd->istate_lock);
1469 
1470 		iscsit_stop_dataout_timer(cmd);
1471 		if (ooo_cmdsn)
1472 			return 0;
1473 		target_execute_cmd(&cmd->se_cmd);
1474 		return 0;
1475 	} else /* DATAOUT_CANNOT_RECOVER */
1476 		return -1;
1477 
1478 	return 0;
1479 }
1480 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1481 
1482 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1483 {
1484 	struct iscsi_cmd *cmd;
1485 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1486 	int rc;
1487 	bool data_crc_failed = false;
1488 
1489 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1490 	if (rc < 0)
1491 		return 0;
1492 	else if (!cmd)
1493 		return 0;
1494 
1495 	rc = iscsit_get_dataout(conn, cmd, hdr);
1496 	if (rc < 0)
1497 		return rc;
1498 	else if (rc > 0)
1499 		data_crc_failed = true;
1500 
1501 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1502 }
1503 
1504 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1505 			 struct iscsi_nopout *hdr)
1506 {
1507 	u32 payload_length = ntoh24(hdr->dlength);
1508 
1509 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1510 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1511 			" not set, protocol error.\n");
1512 		if (!cmd)
1513 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1514 						 (unsigned char *)hdr);
1515 
1516 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1517 					 (unsigned char *)hdr);
1518 	}
1519 
1520 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1521 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1522 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1523 			" error.\n", payload_length,
1524 			conn->conn_ops->MaxXmitDataSegmentLength);
1525 		if (!cmd)
1526 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1527 						 (unsigned char *)hdr);
1528 
1529 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1530 					 (unsigned char *)hdr);
1531 	}
1532 
1533 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1534 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1535 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1536 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1537 		payload_length);
1538 	/*
1539 	 * This is not a response to a Unsolicited NopIN, which means
1540 	 * it can either be a NOPOUT ping request (with a valid ITT),
1541 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1542 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1543 	 * can contain ping data.
1544 	 */
1545 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1546 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1547 		cmd->i_state		= ISTATE_SEND_NOPIN;
1548 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1549 						1 : 0);
1550 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1551 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1552 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1553 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1554 		cmd->data_direction	= DMA_NONE;
1555 	}
1556 
1557 	return 0;
1558 }
1559 EXPORT_SYMBOL(iscsit_setup_nop_out);
1560 
1561 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1562 			   struct iscsi_nopout *hdr)
1563 {
1564 	struct iscsi_cmd *cmd_p = NULL;
1565 	int cmdsn_ret = 0;
1566 	/*
1567 	 * Initiator is expecting a NopIN ping reply..
1568 	 */
1569 	if (hdr->itt != RESERVED_ITT) {
1570 		BUG_ON(!cmd);
1571 
1572 		spin_lock_bh(&conn->cmd_lock);
1573 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1574 		spin_unlock_bh(&conn->cmd_lock);
1575 
1576 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1577 
1578 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1579 			iscsit_add_cmd_to_response_queue(cmd, conn,
1580 							 cmd->i_state);
1581 			return 0;
1582 		}
1583 
1584 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1585 				(unsigned char *)hdr, hdr->cmdsn);
1586                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1587 			return 0;
1588 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1589 			return -1;
1590 
1591 		return 0;
1592 	}
1593 	/*
1594 	 * This was a response to a unsolicited NOPIN ping.
1595 	 */
1596 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1597 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1598 		if (!cmd_p)
1599 			return -EINVAL;
1600 
1601 		iscsit_stop_nopin_response_timer(conn);
1602 
1603 		cmd_p->i_state = ISTATE_REMOVE;
1604 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1605 
1606 		iscsit_start_nopin_timer(conn);
1607 		return 0;
1608 	}
1609 	/*
1610 	 * Otherwise, initiator is not expecting a NOPIN is response.
1611 	 * Just ignore for now.
1612 	 */
1613         return 0;
1614 }
1615 EXPORT_SYMBOL(iscsit_process_nop_out);
1616 
1617 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1618 				 unsigned char *buf)
1619 {
1620 	unsigned char *ping_data = NULL;
1621 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1622 	struct kvec *iov = NULL;
1623 	u32 payload_length = ntoh24(hdr->dlength);
1624 	int ret;
1625 
1626 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1627 	if (ret < 0)
1628 		return 0;
1629 	/*
1630 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1631 	 */
1632 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1633 		u32 checksum, data_crc, padding = 0;
1634 		int niov = 0, rx_got, rx_size = payload_length;
1635 
1636 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1637 		if (!ping_data) {
1638 			pr_err("Unable to allocate memory for"
1639 				" NOPOUT ping data.\n");
1640 			ret = -1;
1641 			goto out;
1642 		}
1643 
1644 		iov = &cmd->iov_misc[0];
1645 		iov[niov].iov_base	= ping_data;
1646 		iov[niov++].iov_len	= payload_length;
1647 
1648 		padding = ((-payload_length) & 3);
1649 		if (padding != 0) {
1650 			pr_debug("Receiving %u additional bytes"
1651 				" for padding.\n", padding);
1652 			iov[niov].iov_base	= &cmd->pad_bytes;
1653 			iov[niov++].iov_len	= padding;
1654 			rx_size += padding;
1655 		}
1656 		if (conn->conn_ops->DataDigest) {
1657 			iov[niov].iov_base	= &checksum;
1658 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1659 			rx_size += ISCSI_CRC_LEN;
1660 		}
1661 
1662 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1663 		if (rx_got != rx_size) {
1664 			ret = -1;
1665 			goto out;
1666 		}
1667 
1668 		if (conn->conn_ops->DataDigest) {
1669 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1670 					ping_data, payload_length,
1671 					padding, cmd->pad_bytes,
1672 					(u8 *)&data_crc);
1673 
1674 			if (checksum != data_crc) {
1675 				pr_err("Ping data CRC32C DataDigest"
1676 				" 0x%08x does not match computed 0x%08x\n",
1677 					checksum, data_crc);
1678 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1679 					pr_err("Unable to recover from"
1680 					" NOPOUT Ping DataCRC failure while in"
1681 						" ERL=0.\n");
1682 					ret = -1;
1683 					goto out;
1684 				} else {
1685 					/*
1686 					 * Silently drop this PDU and let the
1687 					 * initiator plug the CmdSN gap.
1688 					 */
1689 					pr_debug("Dropping NOPOUT"
1690 					" Command CmdSN: 0x%08x due to"
1691 					" DataCRC error.\n", hdr->cmdsn);
1692 					ret = 0;
1693 					goto out;
1694 				}
1695 			} else {
1696 				pr_debug("Got CRC32C DataDigest"
1697 				" 0x%08x for %u bytes of ping data.\n",
1698 					checksum, payload_length);
1699 			}
1700 		}
1701 
1702 		ping_data[payload_length] = '\0';
1703 		/*
1704 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1705 		 */
1706 		cmd->buf_ptr = ping_data;
1707 		cmd->buf_ptr_size = payload_length;
1708 
1709 		pr_debug("Got %u bytes of NOPOUT ping"
1710 			" data.\n", payload_length);
1711 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1712 	}
1713 
1714 	return iscsit_process_nop_out(conn, cmd, hdr);
1715 out:
1716 	if (cmd)
1717 		iscsit_free_cmd(cmd, false);
1718 
1719 	kfree(ping_data);
1720 	return ret;
1721 }
1722 
1723 int
1724 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1725 			   unsigned char *buf)
1726 {
1727 	struct se_tmr_req *se_tmr;
1728 	struct iscsi_tmr_req *tmr_req;
1729 	struct iscsi_tm *hdr;
1730 	int out_of_order_cmdsn = 0, ret;
1731 	bool sess_ref = false;
1732 	u8 function;
1733 
1734 	hdr			= (struct iscsi_tm *) buf;
1735 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1736 	function = hdr->flags;
1737 
1738 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1739 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1740 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1741 		hdr->rtt, hdr->refcmdsn, conn->cid);
1742 
1743 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1744 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1745 	     hdr->rtt != RESERVED_ITT)) {
1746 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1747 		hdr->rtt = RESERVED_ITT;
1748 	}
1749 
1750 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1751 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1752 		pr_err("Task Management Request TASK_REASSIGN not"
1753 			" issued as immediate command, bad iSCSI Initiator"
1754 				"implementation\n");
1755 		return iscsit_add_reject_cmd(cmd,
1756 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1757 	}
1758 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1759 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1760 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1761 
1762 	cmd->data_direction = DMA_NONE;
1763 
1764 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1765 	if (!cmd->tmr_req) {
1766 		pr_err("Unable to allocate memory for"
1767 			" Task Management command!\n");
1768 		return iscsit_add_reject_cmd(cmd,
1769 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1770 					     buf);
1771 	}
1772 
1773 	/*
1774 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1775 	 * LIO-Target $FABRIC_MOD
1776 	 */
1777 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1778 
1779 		u8 tcm_function;
1780 		int ret;
1781 
1782 		transport_init_se_cmd(&cmd->se_cmd,
1783 				      &lio_target_fabric_configfs->tf_ops,
1784 				      conn->sess->se_sess, 0, DMA_NONE,
1785 				      MSG_SIMPLE_TAG, cmd->sense_buffer + 2);
1786 
1787 		target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
1788 		sess_ref = true;
1789 
1790 		switch (function) {
1791 		case ISCSI_TM_FUNC_ABORT_TASK:
1792 			tcm_function = TMR_ABORT_TASK;
1793 			break;
1794 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1795 			tcm_function = TMR_ABORT_TASK_SET;
1796 			break;
1797 		case ISCSI_TM_FUNC_CLEAR_ACA:
1798 			tcm_function = TMR_CLEAR_ACA;
1799 			break;
1800 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1801 			tcm_function = TMR_CLEAR_TASK_SET;
1802 			break;
1803 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1804 			tcm_function = TMR_LUN_RESET;
1805 			break;
1806 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1807 			tcm_function = TMR_TARGET_WARM_RESET;
1808 			break;
1809 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1810 			tcm_function = TMR_TARGET_COLD_RESET;
1811 			break;
1812 		default:
1813 			pr_err("Unknown iSCSI TMR Function:"
1814 			       " 0x%02x\n", function);
1815 			return iscsit_add_reject_cmd(cmd,
1816 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1817 		}
1818 
1819 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1820 					 tcm_function, GFP_KERNEL);
1821 		if (ret < 0)
1822 			return iscsit_add_reject_cmd(cmd,
1823 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1824 
1825 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1826 	}
1827 
1828 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1829 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1830 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1831 	cmd->init_task_tag	= hdr->itt;
1832 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1833 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1834 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1835 	se_tmr			= cmd->se_cmd.se_tmr_req;
1836 	tmr_req			= cmd->tmr_req;
1837 	/*
1838 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1839 	 */
1840 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1841 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1842 					       scsilun_to_int(&hdr->lun));
1843 		if (ret < 0) {
1844 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1845 			goto attach;
1846 		}
1847 	}
1848 
1849 	switch (function) {
1850 	case ISCSI_TM_FUNC_ABORT_TASK:
1851 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1852 		if (se_tmr->response)
1853 			goto attach;
1854 		break;
1855 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1856 	case ISCSI_TM_FUNC_CLEAR_ACA:
1857 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1858 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1859 		break;
1860 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1861 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1862 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1863 			goto attach;
1864 		}
1865 		break;
1866 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1867 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1868 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1869 			goto attach;
1870 		}
1871 		break;
1872 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1873 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1874 		/*
1875 		 * Perform sanity checks on the ExpDataSN only if the
1876 		 * TASK_REASSIGN was successful.
1877 		 */
1878 		if (se_tmr->response)
1879 			break;
1880 
1881 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1882 			return iscsit_add_reject_cmd(cmd,
1883 					ISCSI_REASON_BOOKMARK_INVALID, buf);
1884 		break;
1885 	default:
1886 		pr_err("Unknown TMR function: 0x%02x, protocol"
1887 			" error.\n", function);
1888 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1889 		goto attach;
1890 	}
1891 
1892 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1893 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1894 		se_tmr->call_transport = 1;
1895 attach:
1896 	spin_lock_bh(&conn->cmd_lock);
1897 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1898 	spin_unlock_bh(&conn->cmd_lock);
1899 
1900 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1901 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1902 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1903 			out_of_order_cmdsn = 1;
1904 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1905 			return 0;
1906 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1907 			return -1;
1908 	}
1909 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1910 
1911 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1912 		return 0;
1913 	/*
1914 	 * Found the referenced task, send to transport for processing.
1915 	 */
1916 	if (se_tmr->call_transport)
1917 		return transport_generic_handle_tmr(&cmd->se_cmd);
1918 
1919 	/*
1920 	 * Could not find the referenced LUN, task, or Task Management
1921 	 * command not authorized or supported.  Change state and
1922 	 * let the tx_thread send the response.
1923 	 *
1924 	 * For connection recovery, this is also the default action for
1925 	 * TMR TASK_REASSIGN.
1926 	 */
1927 	if (sess_ref) {
1928 		pr_debug("Handle TMR, using sess_ref=true check\n");
1929 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1930 	}
1931 
1932 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1933 	return 0;
1934 }
1935 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
1936 
1937 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1938 int
1939 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1940 		      struct iscsi_text *hdr)
1941 {
1942 	u32 payload_length = ntoh24(hdr->dlength);
1943 
1944 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1945 		pr_err("Unable to accept text parameter length: %u"
1946 			"greater than MaxXmitDataSegmentLength %u.\n",
1947 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1948 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1949 					 (unsigned char *)hdr);
1950 	}
1951 
1952 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1953 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1954 		hdr->exp_statsn, payload_length);
1955 
1956 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1957 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1958 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1959 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
1960 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1961 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1962 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1963 	cmd->data_direction	= DMA_NONE;
1964 
1965 	return 0;
1966 }
1967 EXPORT_SYMBOL(iscsit_setup_text_cmd);
1968 
1969 int
1970 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1971 			struct iscsi_text *hdr)
1972 {
1973 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
1974 	int cmdsn_ret;
1975 
1976 	if (!text_in) {
1977 		pr_err("Unable to locate text_in buffer for sendtargets"
1978 		       " discovery\n");
1979 		goto reject;
1980 	}
1981 	if (strncmp("SendTargets", text_in, 11) != 0) {
1982 		pr_err("Received Text Data that is not"
1983 			" SendTargets, cannot continue.\n");
1984 		goto reject;
1985 	}
1986 	text_ptr = strchr(text_in, '=');
1987 	if (!text_ptr) {
1988 		pr_err("No \"=\" separator found in Text Data,"
1989 			"  cannot continue.\n");
1990 		goto reject;
1991 	}
1992 	if (!strncmp("=All", text_ptr, 4)) {
1993 		cmd->cmd_flags |= IFC_SENDTARGETS_ALL;
1994 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
1995 		   !strncmp("=eui.", text_ptr, 5)) {
1996 		cmd->cmd_flags |= IFC_SENDTARGETS_SINGLE;
1997 	} else {
1998 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
1999 		goto reject;
2000 	}
2001 
2002 	spin_lock_bh(&conn->cmd_lock);
2003 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2004 	spin_unlock_bh(&conn->cmd_lock);
2005 
2006 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2007 
2008 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2009 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2010 				(unsigned char *)hdr, hdr->cmdsn);
2011 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2012 			return -1;
2013 
2014 		return 0;
2015 	}
2016 
2017 	return iscsit_execute_cmd(cmd, 0);
2018 
2019 reject:
2020 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2021 				 (unsigned char *)hdr);
2022 }
2023 EXPORT_SYMBOL(iscsit_process_text_cmd);
2024 
2025 static int
2026 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2027 		       unsigned char *buf)
2028 {
2029 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2030 	char *text_in = NULL;
2031 	u32 payload_length = ntoh24(hdr->dlength);
2032 	int rx_size, rc;
2033 
2034 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2035 	if (rc < 0)
2036 		return 0;
2037 
2038 	rx_size = payload_length;
2039 	if (payload_length) {
2040 		u32 checksum = 0, data_crc = 0;
2041 		u32 padding = 0, pad_bytes = 0;
2042 		int niov = 0, rx_got;
2043 		struct kvec iov[3];
2044 
2045 		text_in = kzalloc(payload_length, GFP_KERNEL);
2046 		if (!text_in) {
2047 			pr_err("Unable to allocate memory for"
2048 				" incoming text parameters\n");
2049 			goto reject;
2050 		}
2051 		cmd->text_in_ptr = text_in;
2052 
2053 		memset(iov, 0, 3 * sizeof(struct kvec));
2054 		iov[niov].iov_base	= text_in;
2055 		iov[niov++].iov_len	= payload_length;
2056 
2057 		padding = ((-payload_length) & 3);
2058 		if (padding != 0) {
2059 			iov[niov].iov_base = &pad_bytes;
2060 			iov[niov++].iov_len  = padding;
2061 			rx_size += padding;
2062 			pr_debug("Receiving %u additional bytes"
2063 					" for padding.\n", padding);
2064 		}
2065 		if (conn->conn_ops->DataDigest) {
2066 			iov[niov].iov_base	= &checksum;
2067 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2068 			rx_size += ISCSI_CRC_LEN;
2069 		}
2070 
2071 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2072 		if (rx_got != rx_size)
2073 			goto reject;
2074 
2075 		if (conn->conn_ops->DataDigest) {
2076 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
2077 					text_in, payload_length,
2078 					padding, (u8 *)&pad_bytes,
2079 					(u8 *)&data_crc);
2080 
2081 			if (checksum != data_crc) {
2082 				pr_err("Text data CRC32C DataDigest"
2083 					" 0x%08x does not match computed"
2084 					" 0x%08x\n", checksum, data_crc);
2085 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2086 					pr_err("Unable to recover from"
2087 					" Text Data digest failure while in"
2088 						" ERL=0.\n");
2089 					goto reject;
2090 				} else {
2091 					/*
2092 					 * Silently drop this PDU and let the
2093 					 * initiator plug the CmdSN gap.
2094 					 */
2095 					pr_debug("Dropping Text"
2096 					" Command CmdSN: 0x%08x due to"
2097 					" DataCRC error.\n", hdr->cmdsn);
2098 					kfree(text_in);
2099 					return 0;
2100 				}
2101 			} else {
2102 				pr_debug("Got CRC32C DataDigest"
2103 					" 0x%08x for %u bytes of text data.\n",
2104 						checksum, payload_length);
2105 			}
2106 		}
2107 		text_in[payload_length - 1] = '\0';
2108 		pr_debug("Successfully read %d bytes of text"
2109 				" data.\n", payload_length);
2110 	}
2111 
2112 	return iscsit_process_text_cmd(conn, cmd, hdr);
2113 
2114 reject:
2115 	kfree(cmd->text_in_ptr);
2116 	cmd->text_in_ptr = NULL;
2117 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2118 }
2119 EXPORT_SYMBOL(iscsit_handle_text_cmd);
2120 
2121 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2122 {
2123 	struct iscsi_conn *conn_p;
2124 	struct iscsi_session *sess = conn->sess;
2125 
2126 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2127 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2128 
2129 	atomic_set(&sess->session_logout, 1);
2130 	atomic_set(&conn->conn_logout_remove, 1);
2131 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2132 
2133 	iscsit_inc_conn_usage_count(conn);
2134 	iscsit_inc_session_usage_count(sess);
2135 
2136 	spin_lock_bh(&sess->conn_lock);
2137 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2138 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2139 			continue;
2140 
2141 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2142 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2143 	}
2144 	spin_unlock_bh(&sess->conn_lock);
2145 
2146 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2147 
2148 	return 0;
2149 }
2150 
2151 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2152 {
2153 	struct iscsi_conn *l_conn;
2154 	struct iscsi_session *sess = conn->sess;
2155 
2156 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2157 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2158 
2159 	/*
2160 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2161 	 * can arrive on a connection with a differing CID.
2162 	 */
2163 	if (conn->cid == cmd->logout_cid) {
2164 		spin_lock_bh(&conn->state_lock);
2165 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2166 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2167 
2168 		atomic_set(&conn->conn_logout_remove, 1);
2169 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2170 		iscsit_inc_conn_usage_count(conn);
2171 
2172 		spin_unlock_bh(&conn->state_lock);
2173 	} else {
2174 		/*
2175 		 * Handle all different cid CLOSECONNECTION requests in
2176 		 * iscsit_logout_post_handler_diffcid() as to give enough
2177 		 * time for any non immediate command's CmdSN to be
2178 		 * acknowledged on the connection in question.
2179 		 *
2180 		 * Here we simply make sure the CID is still around.
2181 		 */
2182 		l_conn = iscsit_get_conn_from_cid(sess,
2183 				cmd->logout_cid);
2184 		if (!l_conn) {
2185 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2186 			iscsit_add_cmd_to_response_queue(cmd, conn,
2187 					cmd->i_state);
2188 			return 0;
2189 		}
2190 
2191 		iscsit_dec_conn_usage_count(l_conn);
2192 	}
2193 
2194 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2195 
2196 	return 0;
2197 }
2198 
2199 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2200 {
2201 	struct iscsi_session *sess = conn->sess;
2202 
2203 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2204 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2205 
2206 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2207 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2208 			" while ERL!=2.\n");
2209 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2210 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2211 		return 0;
2212 	}
2213 
2214 	if (conn->cid == cmd->logout_cid) {
2215 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2216 			" with CID: %hu on CID: %hu, implementation error.\n",
2217 				cmd->logout_cid, conn->cid);
2218 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2219 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2220 		return 0;
2221 	}
2222 
2223 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2224 
2225 	return 0;
2226 }
2227 
2228 int
2229 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2230 			unsigned char *buf)
2231 {
2232 	int cmdsn_ret, logout_remove = 0;
2233 	u8 reason_code = 0;
2234 	struct iscsi_logout *hdr;
2235 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2236 
2237 	hdr			= (struct iscsi_logout *) buf;
2238 	reason_code		= (hdr->flags & 0x7f);
2239 
2240 	if (tiqn) {
2241 		spin_lock(&tiqn->logout_stats.lock);
2242 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2243 			tiqn->logout_stats.normal_logouts++;
2244 		else
2245 			tiqn->logout_stats.abnormal_logouts++;
2246 		spin_unlock(&tiqn->logout_stats.lock);
2247 	}
2248 
2249 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2250 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2251 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2252 		hdr->cid, conn->cid);
2253 
2254 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2255 		pr_err("Received logout request on connection that"
2256 			" is not in logged in state, ignoring request.\n");
2257 		iscsit_free_cmd(cmd, false);
2258 		return 0;
2259 	}
2260 
2261 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2262 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2263 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2264 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2265 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2266 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2267 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2268 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2269 	cmd->logout_reason      = reason_code;
2270 	cmd->data_direction     = DMA_NONE;
2271 
2272 	/*
2273 	 * We need to sleep in these cases (by returning 1) until the Logout
2274 	 * Response gets sent in the tx thread.
2275 	 */
2276 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2277 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2278 	    be16_to_cpu(hdr->cid) == conn->cid))
2279 		logout_remove = 1;
2280 
2281 	spin_lock_bh(&conn->cmd_lock);
2282 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2283 	spin_unlock_bh(&conn->cmd_lock);
2284 
2285 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2286 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2287 
2288 	/*
2289 	 * Immediate commands are executed, well, immediately.
2290 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2291 	 */
2292 	if (cmd->immediate_cmd) {
2293 		int ret = iscsit_execute_cmd(cmd, 0);
2294 
2295 		if (ret < 0)
2296 			return ret;
2297 	} else {
2298 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2299 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2300 			logout_remove = 0;
2301 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2302 			return -1;
2303 	}
2304 
2305 	return logout_remove;
2306 }
2307 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2308 
2309 static int iscsit_handle_snack(
2310 	struct iscsi_conn *conn,
2311 	unsigned char *buf)
2312 {
2313 	struct iscsi_snack *hdr;
2314 
2315 	hdr			= (struct iscsi_snack *) buf;
2316 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2317 
2318 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2319 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2320 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2321 			hdr->begrun, hdr->runlength, conn->cid);
2322 
2323 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2324 		pr_err("Initiator sent SNACK request while in"
2325 			" ErrorRecoveryLevel=0.\n");
2326 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2327 					 buf);
2328 	}
2329 	/*
2330 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2331 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2332 	 */
2333 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2334 	case 0:
2335 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2336 			hdr->itt,
2337 			be32_to_cpu(hdr->ttt),
2338 			be32_to_cpu(hdr->begrun),
2339 			be32_to_cpu(hdr->runlength));
2340 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2341 		return iscsit_handle_status_snack(conn, hdr->itt,
2342 			be32_to_cpu(hdr->ttt),
2343 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2344 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2345 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2346 			be32_to_cpu(hdr->begrun),
2347 			be32_to_cpu(hdr->runlength));
2348 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2349 		/* FIXME: Support R-Data SNACK */
2350 		pr_err("R-Data SNACK Not Supported.\n");
2351 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2352 					 buf);
2353 	default:
2354 		pr_err("Unknown SNACK type 0x%02x, protocol"
2355 			" error.\n", hdr->flags & 0x0f);
2356 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2357 					 buf);
2358 	}
2359 
2360 	return 0;
2361 }
2362 
2363 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2364 {
2365 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2366 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2367 		wait_for_completion_interruptible_timeout(
2368 					&conn->rx_half_close_comp,
2369 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2370 	}
2371 }
2372 
2373 static int iscsit_handle_immediate_data(
2374 	struct iscsi_cmd *cmd,
2375 	struct iscsi_scsi_req *hdr,
2376 	u32 length)
2377 {
2378 	int iov_ret, rx_got = 0, rx_size = 0;
2379 	u32 checksum, iov_count = 0, padding = 0;
2380 	struct iscsi_conn *conn = cmd->conn;
2381 	struct kvec *iov;
2382 
2383 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2384 	if (iov_ret < 0)
2385 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2386 
2387 	rx_size = length;
2388 	iov_count = iov_ret;
2389 	iov = &cmd->iov_data[0];
2390 
2391 	padding = ((-length) & 3);
2392 	if (padding != 0) {
2393 		iov[iov_count].iov_base	= cmd->pad_bytes;
2394 		iov[iov_count++].iov_len = padding;
2395 		rx_size += padding;
2396 	}
2397 
2398 	if (conn->conn_ops->DataDigest) {
2399 		iov[iov_count].iov_base		= &checksum;
2400 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2401 		rx_size += ISCSI_CRC_LEN;
2402 	}
2403 
2404 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2405 
2406 	iscsit_unmap_iovec(cmd);
2407 
2408 	if (rx_got != rx_size) {
2409 		iscsit_rx_thread_wait_for_tcp(conn);
2410 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2411 	}
2412 
2413 	if (conn->conn_ops->DataDigest) {
2414 		u32 data_crc;
2415 
2416 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2417 						    cmd->write_data_done, length, padding,
2418 						    cmd->pad_bytes);
2419 
2420 		if (checksum != data_crc) {
2421 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2422 				" does not match computed 0x%08x\n", checksum,
2423 				data_crc);
2424 
2425 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2426 				pr_err("Unable to recover from"
2427 					" Immediate Data digest failure while"
2428 					" in ERL=0.\n");
2429 				iscsit_reject_cmd(cmd,
2430 						ISCSI_REASON_DATA_DIGEST_ERROR,
2431 						(unsigned char *)hdr);
2432 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2433 			} else {
2434 				iscsit_reject_cmd(cmd,
2435 						ISCSI_REASON_DATA_DIGEST_ERROR,
2436 						(unsigned char *)hdr);
2437 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2438 			}
2439 		} else {
2440 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2441 				" %u bytes of Immediate Data\n", checksum,
2442 				length);
2443 		}
2444 	}
2445 
2446 	cmd->write_data_done += length;
2447 
2448 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2449 		spin_lock_bh(&cmd->istate_lock);
2450 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2451 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2452 		spin_unlock_bh(&cmd->istate_lock);
2453 	}
2454 
2455 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2456 }
2457 
2458 /*
2459  *	Called with sess->conn_lock held.
2460  */
2461 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2462 	with active network interface */
2463 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2464 {
2465 	struct iscsi_cmd *cmd;
2466 	struct iscsi_conn *conn_p;
2467 
2468 	/*
2469 	 * Only send a Asynchronous Message on connections whos network
2470 	 * interface is still functional.
2471 	 */
2472 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2473 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2474 			iscsit_inc_conn_usage_count(conn_p);
2475 			break;
2476 		}
2477 	}
2478 
2479 	if (!conn_p)
2480 		return;
2481 
2482 	cmd = iscsit_allocate_cmd(conn_p, GFP_ATOMIC);
2483 	if (!cmd) {
2484 		iscsit_dec_conn_usage_count(conn_p);
2485 		return;
2486 	}
2487 
2488 	cmd->logout_cid = conn->cid;
2489 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2490 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2491 
2492 	spin_lock_bh(&conn_p->cmd_lock);
2493 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2494 	spin_unlock_bh(&conn_p->cmd_lock);
2495 
2496 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2497 	iscsit_dec_conn_usage_count(conn_p);
2498 }
2499 
2500 static int iscsit_send_conn_drop_async_message(
2501 	struct iscsi_cmd *cmd,
2502 	struct iscsi_conn *conn)
2503 {
2504 	struct iscsi_async *hdr;
2505 
2506 	cmd->tx_size = ISCSI_HDR_LEN;
2507 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2508 
2509 	hdr			= (struct iscsi_async *) cmd->pdu;
2510 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2511 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2512 	cmd->init_task_tag	= RESERVED_ITT;
2513 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2514 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2515 	cmd->stat_sn		= conn->stat_sn++;
2516 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2517 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2518 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2519 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2520 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2521 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2522 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2523 
2524 	if (conn->conn_ops->HeaderDigest) {
2525 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2526 
2527 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2528 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2529 
2530 		cmd->tx_size += ISCSI_CRC_LEN;
2531 		pr_debug("Attaching CRC32C HeaderDigest to"
2532 			" Async Message 0x%08x\n", *header_digest);
2533 	}
2534 
2535 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2536 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2537 	cmd->iov_misc_count		= 1;
2538 
2539 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2540 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2541 			cmd->logout_cid, conn->cid);
2542 	return 0;
2543 }
2544 
2545 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2546 {
2547 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2548 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2549 		wait_for_completion_interruptible_timeout(
2550 					&conn->tx_half_close_comp,
2551 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2552 	}
2553 }
2554 
2555 static void
2556 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2557 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2558 			bool set_statsn)
2559 {
2560 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2561 	hdr->flags		= datain->flags;
2562 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2563 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2564 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2565 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2566 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2567 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2568 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2569 		}
2570 	}
2571 	hton24(hdr->dlength, datain->length);
2572 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2573 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2574 				(struct scsi_lun *)&hdr->lun);
2575 	else
2576 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2577 
2578 	hdr->itt		= cmd->init_task_tag;
2579 
2580 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2581 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2582 	else
2583 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2584 	if (set_statsn)
2585 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2586 	else
2587 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2588 
2589 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2590 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2591 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2592 	hdr->offset		= cpu_to_be32(datain->offset);
2593 
2594 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2595 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2596 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2597 		ntohl(hdr->offset), datain->length, conn->cid);
2598 }
2599 
2600 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2601 {
2602 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2603 	struct iscsi_datain datain;
2604 	struct iscsi_datain_req *dr;
2605 	struct kvec *iov;
2606 	u32 iov_count = 0, tx_size = 0;
2607 	int eodr = 0, ret, iov_ret;
2608 	bool set_statsn = false;
2609 
2610 	memset(&datain, 0, sizeof(struct iscsi_datain));
2611 	dr = iscsit_get_datain_values(cmd, &datain);
2612 	if (!dr) {
2613 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2614 				cmd->init_task_tag);
2615 		return -1;
2616 	}
2617 	/*
2618 	 * Be paranoid and double check the logic for now.
2619 	 */
2620 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2621 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2622 			" datain.length: %u exceeds cmd->data_length: %u\n",
2623 			cmd->init_task_tag, datain.offset, datain.length,
2624 			cmd->se_cmd.data_length);
2625 		return -1;
2626 	}
2627 
2628 	spin_lock_bh(&conn->sess->session_stats_lock);
2629 	conn->sess->tx_data_octets += datain.length;
2630 	if (conn->sess->se_sess->se_node_acl) {
2631 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
2632 		conn->sess->se_sess->se_node_acl->read_bytes += datain.length;
2633 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
2634 	}
2635 	spin_unlock_bh(&conn->sess->session_stats_lock);
2636 	/*
2637 	 * Special case for successfully execution w/ both DATAIN
2638 	 * and Sense Data.
2639 	 */
2640 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2641 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2642 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2643 	else {
2644 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2645 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2646 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2647 			cmd->stat_sn = conn->stat_sn++;
2648 			set_statsn = true;
2649 		} else if (dr->dr_complete ==
2650 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2651 			set_statsn = true;
2652 	}
2653 
2654 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2655 
2656 	iov = &cmd->iov_data[0];
2657 	iov[iov_count].iov_base	= cmd->pdu;
2658 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2659 	tx_size += ISCSI_HDR_LEN;
2660 
2661 	if (conn->conn_ops->HeaderDigest) {
2662 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2663 
2664 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
2665 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2666 
2667 		iov[0].iov_len += ISCSI_CRC_LEN;
2668 		tx_size += ISCSI_CRC_LEN;
2669 
2670 		pr_debug("Attaching CRC32 HeaderDigest"
2671 			" for DataIN PDU 0x%08x\n", *header_digest);
2672 	}
2673 
2674 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
2675 				datain.offset, datain.length);
2676 	if (iov_ret < 0)
2677 		return -1;
2678 
2679 	iov_count += iov_ret;
2680 	tx_size += datain.length;
2681 
2682 	cmd->padding = ((-datain.length) & 3);
2683 	if (cmd->padding) {
2684 		iov[iov_count].iov_base		= cmd->pad_bytes;
2685 		iov[iov_count++].iov_len	= cmd->padding;
2686 		tx_size += cmd->padding;
2687 
2688 		pr_debug("Attaching %u padding bytes\n",
2689 				cmd->padding);
2690 	}
2691 	if (conn->conn_ops->DataDigest) {
2692 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2693 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2694 
2695 		iov[iov_count].iov_base	= &cmd->data_crc;
2696 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2697 		tx_size += ISCSI_CRC_LEN;
2698 
2699 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2700 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2701 	}
2702 
2703 	cmd->iov_data_count = iov_count;
2704 	cmd->tx_size = tx_size;
2705 
2706 	/* sendpage is preferred but can't insert markers */
2707 	if (!conn->conn_ops->IFMarker)
2708 		ret = iscsit_fe_sendpage_sg(cmd, conn);
2709 	else
2710 		ret = iscsit_send_tx_data(cmd, conn, 0);
2711 
2712 	iscsit_unmap_iovec(cmd);
2713 
2714 	if (ret < 0) {
2715 		iscsit_tx_thread_wait_for_tcp(conn);
2716 		return ret;
2717 	}
2718 
2719 	if (dr->dr_complete) {
2720 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2721 				2 : 1;
2722 		iscsit_free_datain_req(cmd, dr);
2723 	}
2724 
2725 	return eodr;
2726 }
2727 
2728 int
2729 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2730 			struct iscsi_logout_rsp *hdr)
2731 {
2732 	struct iscsi_conn *logout_conn = NULL;
2733 	struct iscsi_conn_recovery *cr = NULL;
2734 	struct iscsi_session *sess = conn->sess;
2735 	/*
2736 	 * The actual shutting down of Sessions and/or Connections
2737 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2738 	 * is done in scsi_logout_post_handler().
2739 	 */
2740 	switch (cmd->logout_reason) {
2741 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2742 		pr_debug("iSCSI session logout successful, setting"
2743 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2744 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2745 		break;
2746 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2747 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2748 			break;
2749 		/*
2750 		 * For CLOSECONNECTION logout requests carrying
2751 		 * a matching logout CID -> local CID, the reference
2752 		 * for the local CID will have been incremented in
2753 		 * iscsi_logout_closeconnection().
2754 		 *
2755 		 * For CLOSECONNECTION logout requests carrying
2756 		 * a different CID than the connection it arrived
2757 		 * on, the connection responding to cmd->logout_cid
2758 		 * is stopped in iscsit_logout_post_handler_diffcid().
2759 		 */
2760 
2761 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2762 			" successful.\n", cmd->logout_cid, conn->cid);
2763 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2764 		break;
2765 	case ISCSI_LOGOUT_REASON_RECOVERY:
2766 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2767 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2768 			break;
2769 		/*
2770 		 * If the connection is still active from our point of view
2771 		 * force connection recovery to occur.
2772 		 */
2773 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2774 				cmd->logout_cid);
2775 		if (logout_conn) {
2776 			iscsit_connection_reinstatement_rcfr(logout_conn);
2777 			iscsit_dec_conn_usage_count(logout_conn);
2778 		}
2779 
2780 		cr = iscsit_get_inactive_connection_recovery_entry(
2781 				conn->sess, cmd->logout_cid);
2782 		if (!cr) {
2783 			pr_err("Unable to locate CID: %hu for"
2784 			" REMOVECONNFORRECOVERY Logout Request.\n",
2785 				cmd->logout_cid);
2786 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2787 			break;
2788 		}
2789 
2790 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2791 
2792 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2793 			" for recovery for CID: %hu on CID: %hu successful.\n",
2794 				cmd->logout_cid, conn->cid);
2795 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2796 		break;
2797 	default:
2798 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2799 				cmd->logout_reason);
2800 		return -1;
2801 	}
2802 
2803 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2804 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2805 	hdr->response		= cmd->logout_response;
2806 	hdr->itt		= cmd->init_task_tag;
2807 	cmd->stat_sn		= conn->stat_sn++;
2808 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2809 
2810 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2811 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2812 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2813 
2814 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2815 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2816 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2817 		cmd->logout_cid, conn->cid);
2818 
2819 	return 0;
2820 }
2821 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2822 
2823 static int
2824 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2825 {
2826 	struct kvec *iov;
2827 	int niov = 0, tx_size, rc;
2828 
2829 	rc = iscsit_build_logout_rsp(cmd, conn,
2830 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2831 	if (rc < 0)
2832 		return rc;
2833 
2834 	tx_size = ISCSI_HDR_LEN;
2835 	iov = &cmd->iov_misc[0];
2836 	iov[niov].iov_base	= cmd->pdu;
2837 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2838 
2839 	if (conn->conn_ops->HeaderDigest) {
2840 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2841 
2842 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, &cmd->pdu[0],
2843 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2844 
2845 		iov[0].iov_len += ISCSI_CRC_LEN;
2846 		tx_size += ISCSI_CRC_LEN;
2847 		pr_debug("Attaching CRC32C HeaderDigest to"
2848 			" Logout Response 0x%08x\n", *header_digest);
2849 	}
2850 	cmd->iov_misc_count = niov;
2851 	cmd->tx_size = tx_size;
2852 
2853 	return 0;
2854 }
2855 
2856 void
2857 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2858 		       struct iscsi_nopin *hdr, bool nopout_response)
2859 {
2860 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2861 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2862         hton24(hdr->dlength, cmd->buf_ptr_size);
2863 	if (nopout_response)
2864 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2865 	hdr->itt		= cmd->init_task_tag;
2866 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2867 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2868 				  conn->stat_sn;
2869 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2870 
2871 	if (nopout_response)
2872 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2873 
2874 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2875 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2876 
2877 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2878 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2879 		"Solicitied" : "Unsolicitied", cmd->init_task_tag,
2880 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2881 }
2882 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2883 
2884 /*
2885  *	Unsolicited NOPIN, either requesting a response or not.
2886  */
2887 static int iscsit_send_unsolicited_nopin(
2888 	struct iscsi_cmd *cmd,
2889 	struct iscsi_conn *conn,
2890 	int want_response)
2891 {
2892 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2893 	int tx_size = ISCSI_HDR_LEN, ret;
2894 
2895 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
2896 
2897 	if (conn->conn_ops->HeaderDigest) {
2898 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2899 
2900 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2901 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2902 
2903 		tx_size += ISCSI_CRC_LEN;
2904 		pr_debug("Attaching CRC32C HeaderDigest to"
2905 			" NopIN 0x%08x\n", *header_digest);
2906 	}
2907 
2908 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2909 	cmd->iov_misc[0].iov_len	= tx_size;
2910 	cmd->iov_misc_count	= 1;
2911 	cmd->tx_size		= tx_size;
2912 
2913 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2914 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2915 
2916 	ret = iscsit_send_tx_data(cmd, conn, 1);
2917 	if (ret < 0) {
2918 		iscsit_tx_thread_wait_for_tcp(conn);
2919 		return ret;
2920 	}
2921 
2922 	spin_lock_bh(&cmd->istate_lock);
2923 	cmd->i_state = want_response ?
2924 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2925 	spin_unlock_bh(&cmd->istate_lock);
2926 
2927 	return 0;
2928 }
2929 
2930 static int
2931 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2932 {
2933 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2934 	struct kvec *iov;
2935 	u32 padding = 0;
2936 	int niov = 0, tx_size;
2937 
2938 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
2939 
2940 	tx_size = ISCSI_HDR_LEN;
2941 	iov = &cmd->iov_misc[0];
2942 	iov[niov].iov_base	= cmd->pdu;
2943 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2944 
2945 	if (conn->conn_ops->HeaderDigest) {
2946 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2947 
2948 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2949 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2950 
2951 		iov[0].iov_len += ISCSI_CRC_LEN;
2952 		tx_size += ISCSI_CRC_LEN;
2953 		pr_debug("Attaching CRC32C HeaderDigest"
2954 			" to NopIn 0x%08x\n", *header_digest);
2955 	}
2956 
2957 	/*
2958 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2959 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2960 	 */
2961 	if (cmd->buf_ptr_size) {
2962 		iov[niov].iov_base	= cmd->buf_ptr;
2963 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2964 		tx_size += cmd->buf_ptr_size;
2965 
2966 		pr_debug("Echoing back %u bytes of ping"
2967 			" data.\n", cmd->buf_ptr_size);
2968 
2969 		padding = ((-cmd->buf_ptr_size) & 3);
2970 		if (padding != 0) {
2971 			iov[niov].iov_base = &cmd->pad_bytes;
2972 			iov[niov++].iov_len = padding;
2973 			tx_size += padding;
2974 			pr_debug("Attaching %u additional"
2975 				" padding bytes.\n", padding);
2976 		}
2977 		if (conn->conn_ops->DataDigest) {
2978 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2979 				cmd->buf_ptr, cmd->buf_ptr_size,
2980 				padding, (u8 *)&cmd->pad_bytes,
2981 				(u8 *)&cmd->data_crc);
2982 
2983 			iov[niov].iov_base = &cmd->data_crc;
2984 			iov[niov++].iov_len = ISCSI_CRC_LEN;
2985 			tx_size += ISCSI_CRC_LEN;
2986 			pr_debug("Attached DataDigest for %u"
2987 				" bytes of ping data, CRC 0x%08x\n",
2988 				cmd->buf_ptr_size, cmd->data_crc);
2989 		}
2990 	}
2991 
2992 	cmd->iov_misc_count = niov;
2993 	cmd->tx_size = tx_size;
2994 
2995 	return 0;
2996 }
2997 
2998 static int iscsit_send_r2t(
2999 	struct iscsi_cmd *cmd,
3000 	struct iscsi_conn *conn)
3001 {
3002 	int tx_size = 0;
3003 	struct iscsi_r2t *r2t;
3004 	struct iscsi_r2t_rsp *hdr;
3005 	int ret;
3006 
3007 	r2t = iscsit_get_r2t_from_list(cmd);
3008 	if (!r2t)
3009 		return -1;
3010 
3011 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3012 	memset(hdr, 0, ISCSI_HDR_LEN);
3013 	hdr->opcode		= ISCSI_OP_R2T;
3014 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3015 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3016 			(struct scsi_lun *)&hdr->lun);
3017 	hdr->itt		= cmd->init_task_tag;
3018 	spin_lock_bh(&conn->sess->ttt_lock);
3019 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
3020 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
3021 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
3022 	spin_unlock_bh(&conn->sess->ttt_lock);
3023 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3024 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3025 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3026 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3027 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3028 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3029 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3030 
3031 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3032 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3033 	tx_size += ISCSI_HDR_LEN;
3034 
3035 	if (conn->conn_ops->HeaderDigest) {
3036 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3037 
3038 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3039 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3040 
3041 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3042 		tx_size += ISCSI_CRC_LEN;
3043 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
3044 			" PDU 0x%08x\n", *header_digest);
3045 	}
3046 
3047 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3048 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3049 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3050 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3051 			r2t->offset, r2t->xfer_len, conn->cid);
3052 
3053 	cmd->iov_misc_count = 1;
3054 	cmd->tx_size = tx_size;
3055 
3056 	spin_lock_bh(&cmd->r2t_lock);
3057 	r2t->sent_r2t = 1;
3058 	spin_unlock_bh(&cmd->r2t_lock);
3059 
3060 	ret = iscsit_send_tx_data(cmd, conn, 1);
3061 	if (ret < 0) {
3062 		iscsit_tx_thread_wait_for_tcp(conn);
3063 		return ret;
3064 	}
3065 
3066 	spin_lock_bh(&cmd->dataout_timeout_lock);
3067 	iscsit_start_dataout_timer(cmd, conn);
3068 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3069 
3070 	return 0;
3071 }
3072 
3073 /*
3074  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3075  *		connection recovery.
3076  */
3077 int iscsit_build_r2ts_for_cmd(
3078 	struct iscsi_conn *conn,
3079 	struct iscsi_cmd *cmd,
3080 	bool recovery)
3081 {
3082 	int first_r2t = 1;
3083 	u32 offset = 0, xfer_len = 0;
3084 
3085 	spin_lock_bh(&cmd->r2t_lock);
3086 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3087 		spin_unlock_bh(&cmd->r2t_lock);
3088 		return 0;
3089 	}
3090 
3091 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3092 	    !recovery)
3093 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3094 
3095 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3096 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3097 			offset = cmd->r2t_offset;
3098 
3099 			if (first_r2t && recovery) {
3100 				int new_data_end = offset +
3101 					conn->sess->sess_ops->MaxBurstLength -
3102 					cmd->next_burst_len;
3103 
3104 				if (new_data_end > cmd->se_cmd.data_length)
3105 					xfer_len = cmd->se_cmd.data_length - offset;
3106 				else
3107 					xfer_len =
3108 						conn->sess->sess_ops->MaxBurstLength -
3109 						cmd->next_burst_len;
3110 			} else {
3111 				int new_data_end = offset +
3112 					conn->sess->sess_ops->MaxBurstLength;
3113 
3114 				if (new_data_end > cmd->se_cmd.data_length)
3115 					xfer_len = cmd->se_cmd.data_length - offset;
3116 				else
3117 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3118 			}
3119 			cmd->r2t_offset += xfer_len;
3120 
3121 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3122 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3123 		} else {
3124 			struct iscsi_seq *seq;
3125 
3126 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3127 			if (!seq) {
3128 				spin_unlock_bh(&cmd->r2t_lock);
3129 				return -1;
3130 			}
3131 
3132 			offset = seq->offset;
3133 			xfer_len = seq->xfer_len;
3134 
3135 			if (cmd->seq_send_order == cmd->seq_count)
3136 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3137 		}
3138 		cmd->outstanding_r2ts++;
3139 		first_r2t = 0;
3140 
3141 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3142 			spin_unlock_bh(&cmd->r2t_lock);
3143 			return -1;
3144 		}
3145 
3146 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3147 			break;
3148 	}
3149 	spin_unlock_bh(&cmd->r2t_lock);
3150 
3151 	return 0;
3152 }
3153 
3154 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3155 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3156 {
3157 	if (inc_stat_sn)
3158 		cmd->stat_sn = conn->stat_sn++;
3159 
3160 	spin_lock_bh(&conn->sess->session_stats_lock);
3161 	conn->sess->rsp_pdus++;
3162 	spin_unlock_bh(&conn->sess->session_stats_lock);
3163 
3164 	memset(hdr, 0, ISCSI_HDR_LEN);
3165 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3166 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3167 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3168 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3169 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3170 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3171 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3172 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3173 	}
3174 	hdr->response		= cmd->iscsi_response;
3175 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3176 	hdr->itt		= cmd->init_task_tag;
3177 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3178 
3179 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3180 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3181 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3182 
3183 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3184 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3185 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3186 		cmd->se_cmd.scsi_status, conn->cid);
3187 }
3188 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3189 
3190 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3191 {
3192 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3193 	struct kvec *iov;
3194 	u32 padding = 0, tx_size = 0;
3195 	int iov_count = 0;
3196 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3197 
3198 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3199 
3200 	iov = &cmd->iov_misc[0];
3201 	iov[iov_count].iov_base	= cmd->pdu;
3202 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3203 	tx_size += ISCSI_HDR_LEN;
3204 
3205 	/*
3206 	 * Attach SENSE DATA payload to iSCSI Response PDU
3207 	 */
3208 	if (cmd->se_cmd.sense_buffer &&
3209 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3210 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3211 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3212 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3213 
3214 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3215 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3216 		iov[iov_count].iov_base	= cmd->sense_buffer;
3217 		iov[iov_count++].iov_len =
3218 				(cmd->se_cmd.scsi_sense_length + padding);
3219 		tx_size += cmd->se_cmd.scsi_sense_length;
3220 
3221 		if (padding) {
3222 			memset(cmd->sense_buffer +
3223 				cmd->se_cmd.scsi_sense_length, 0, padding);
3224 			tx_size += padding;
3225 			pr_debug("Adding %u bytes of padding to"
3226 				" SENSE.\n", padding);
3227 		}
3228 
3229 		if (conn->conn_ops->DataDigest) {
3230 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3231 				cmd->sense_buffer,
3232 				(cmd->se_cmd.scsi_sense_length + padding),
3233 				0, NULL, (u8 *)&cmd->data_crc);
3234 
3235 			iov[iov_count].iov_base    = &cmd->data_crc;
3236 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3237 			tx_size += ISCSI_CRC_LEN;
3238 
3239 			pr_debug("Attaching CRC32 DataDigest for"
3240 				" SENSE, %u bytes CRC 0x%08x\n",
3241 				(cmd->se_cmd.scsi_sense_length + padding),
3242 				cmd->data_crc);
3243 		}
3244 
3245 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3246 				" Response PDU\n",
3247 				cmd->se_cmd.scsi_sense_length);
3248 	}
3249 
3250 	if (conn->conn_ops->HeaderDigest) {
3251 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3252 
3253 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
3254 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3255 
3256 		iov[0].iov_len += ISCSI_CRC_LEN;
3257 		tx_size += ISCSI_CRC_LEN;
3258 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3259 				" PDU 0x%08x\n", *header_digest);
3260 	}
3261 
3262 	cmd->iov_misc_count = iov_count;
3263 	cmd->tx_size = tx_size;
3264 
3265 	return 0;
3266 }
3267 
3268 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3269 {
3270 	switch (se_tmr->response) {
3271 	case TMR_FUNCTION_COMPLETE:
3272 		return ISCSI_TMF_RSP_COMPLETE;
3273 	case TMR_TASK_DOES_NOT_EXIST:
3274 		return ISCSI_TMF_RSP_NO_TASK;
3275 	case TMR_LUN_DOES_NOT_EXIST:
3276 		return ISCSI_TMF_RSP_NO_LUN;
3277 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3278 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3279 	case TMR_FUNCTION_REJECTED:
3280 	default:
3281 		return ISCSI_TMF_RSP_REJECTED;
3282 	}
3283 }
3284 
3285 void
3286 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3287 			  struct iscsi_tm_rsp *hdr)
3288 {
3289 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3290 
3291 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3292 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3293 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3294 	hdr->itt		= cmd->init_task_tag;
3295 	cmd->stat_sn		= conn->stat_sn++;
3296 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3297 
3298 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3299 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3300 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3301 
3302 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3303 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3304 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3305 }
3306 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3307 
3308 static int
3309 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3310 {
3311 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3312 	u32 tx_size = 0;
3313 
3314 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3315 
3316 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3317 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3318 	tx_size += ISCSI_HDR_LEN;
3319 
3320 	if (conn->conn_ops->HeaderDigest) {
3321 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3322 
3323 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3324 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3325 
3326 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3327 		tx_size += ISCSI_CRC_LEN;
3328 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3329 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3330 	}
3331 
3332 	cmd->iov_misc_count = 1;
3333 	cmd->tx_size = tx_size;
3334 
3335 	return 0;
3336 }
3337 
3338 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3339 {
3340 	bool ret = false;
3341 
3342 	if (np->np_sockaddr.ss_family == AF_INET6) {
3343 		const struct sockaddr_in6 sin6 = {
3344 			.sin6_addr = IN6ADDR_ANY_INIT };
3345 		struct sockaddr_in6 *sock_in6 =
3346 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3347 
3348 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3349 				sin6.sin6_addr.s6_addr, 16))
3350 			ret = true;
3351 	} else {
3352 		struct sockaddr_in * sock_in =
3353 			(struct sockaddr_in *)&np->np_sockaddr;
3354 
3355 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3356 			ret = true;
3357 	}
3358 
3359 	return ret;
3360 }
3361 
3362 #define SENDTARGETS_BUF_LIMIT 32768U
3363 
3364 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3365 {
3366 	char *payload = NULL;
3367 	struct iscsi_conn *conn = cmd->conn;
3368 	struct iscsi_portal_group *tpg;
3369 	struct iscsi_tiqn *tiqn;
3370 	struct iscsi_tpg_np *tpg_np;
3371 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3372 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3373 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3374 
3375 	buffer_len = max(conn->conn_ops->MaxRecvDataSegmentLength,
3376 			 SENDTARGETS_BUF_LIMIT);
3377 
3378 	payload = kzalloc(buffer_len, GFP_KERNEL);
3379 	if (!payload) {
3380 		pr_err("Unable to allocate memory for sendtargets"
3381 				" response.\n");
3382 		return -ENOMEM;
3383 	}
3384 	/*
3385 	 * Locate pointer to iqn./eui. string for IFC_SENDTARGETS_SINGLE
3386 	 * explicit case..
3387 	 */
3388 	if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) {
3389 		text_ptr = strchr(text_in, '=');
3390 		if (!text_ptr) {
3391 			pr_err("Unable to locate '=' string in text_in:"
3392 			       " %s\n", text_in);
3393 			kfree(payload);
3394 			return -EINVAL;
3395 		}
3396 		/*
3397 		 * Skip over '=' character..
3398 		 */
3399 		text_ptr += 1;
3400 	}
3401 
3402 	spin_lock(&tiqn_lock);
3403 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3404 		if ((cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) &&
3405 		     strcmp(tiqn->tiqn, text_ptr)) {
3406 			continue;
3407 		}
3408 
3409 		len = sprintf(buf, "TargetName=%s", tiqn->tiqn);
3410 		len += 1;
3411 
3412 		if ((len + payload_len) > buffer_len) {
3413 			end_of_buf = 1;
3414 			goto eob;
3415 		}
3416 		memcpy(payload + payload_len, buf, len);
3417 		payload_len += len;
3418 
3419 		spin_lock(&tiqn->tiqn_tpg_lock);
3420 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3421 
3422 			spin_lock(&tpg->tpg_state_lock);
3423 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3424 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3425 				spin_unlock(&tpg->tpg_state_lock);
3426 				continue;
3427 			}
3428 			spin_unlock(&tpg->tpg_state_lock);
3429 
3430 			spin_lock(&tpg->tpg_np_lock);
3431 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3432 						tpg_np_list) {
3433 				struct iscsi_np *np = tpg_np->tpg_np;
3434 				bool inaddr_any = iscsit_check_inaddr_any(np);
3435 
3436 				len = sprintf(buf, "TargetAddress="
3437 					"%s:%hu,%hu",
3438 					(inaddr_any == false) ?
3439 						np->np_ip : conn->local_ip,
3440 					(inaddr_any == false) ?
3441 						np->np_port : conn->local_port,
3442 					tpg->tpgt);
3443 				len += 1;
3444 
3445 				if ((len + payload_len) > buffer_len) {
3446 					spin_unlock(&tpg->tpg_np_lock);
3447 					spin_unlock(&tiqn->tiqn_tpg_lock);
3448 					end_of_buf = 1;
3449 					goto eob;
3450 				}
3451 				memcpy(payload + payload_len, buf, len);
3452 				payload_len += len;
3453 			}
3454 			spin_unlock(&tpg->tpg_np_lock);
3455 		}
3456 		spin_unlock(&tiqn->tiqn_tpg_lock);
3457 eob:
3458 		if (end_of_buf)
3459 			break;
3460 
3461 		if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE)
3462 			break;
3463 	}
3464 	spin_unlock(&tiqn_lock);
3465 
3466 	cmd->buf_ptr = payload;
3467 
3468 	return payload_len;
3469 }
3470 
3471 int
3472 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3473 		      struct iscsi_text_rsp *hdr)
3474 {
3475 	int text_length, padding;
3476 
3477 	text_length = iscsit_build_sendtargets_response(cmd);
3478 	if (text_length < 0)
3479 		return text_length;
3480 
3481 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3482 	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3483 	padding = ((-text_length) & 3);
3484 	hton24(hdr->dlength, text_length);
3485 	hdr->itt = cmd->init_task_tag;
3486 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3487 	cmd->stat_sn = conn->stat_sn++;
3488 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3489 
3490 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3491 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3492 	hdr->max_cmdsn = cpu_to_be32(conn->sess->max_cmd_sn);
3493 
3494 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3495 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3496 		text_length, conn->cid);
3497 
3498 	return text_length + padding;
3499 }
3500 EXPORT_SYMBOL(iscsit_build_text_rsp);
3501 
3502 /*
3503  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3504  *	MaxRecvDataSegmentLength.
3505  */
3506 static int iscsit_send_text_rsp(
3507 	struct iscsi_cmd *cmd,
3508 	struct iscsi_conn *conn)
3509 {
3510 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3511 	struct kvec *iov;
3512 	u32 tx_size = 0;
3513 	int text_length, iov_count = 0, rc;
3514 
3515 	rc = iscsit_build_text_rsp(cmd, conn, hdr);
3516 	if (rc < 0)
3517 		return rc;
3518 
3519 	text_length = rc;
3520 	iov = &cmd->iov_misc[0];
3521 	iov[iov_count].iov_base = cmd->pdu;
3522 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3523 	iov[iov_count].iov_base	= cmd->buf_ptr;
3524 	iov[iov_count++].iov_len = text_length;
3525 
3526 	tx_size += (ISCSI_HDR_LEN + text_length);
3527 
3528 	if (conn->conn_ops->HeaderDigest) {
3529 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3530 
3531 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3532 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3533 
3534 		iov[0].iov_len += ISCSI_CRC_LEN;
3535 		tx_size += ISCSI_CRC_LEN;
3536 		pr_debug("Attaching CRC32 HeaderDigest for"
3537 			" Text Response PDU 0x%08x\n", *header_digest);
3538 	}
3539 
3540 	if (conn->conn_ops->DataDigest) {
3541 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3542 				cmd->buf_ptr, text_length,
3543 				0, NULL, (u8 *)&cmd->data_crc);
3544 
3545 		iov[iov_count].iov_base	= &cmd->data_crc;
3546 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3547 		tx_size	+= ISCSI_CRC_LEN;
3548 
3549 		pr_debug("Attaching DataDigest for %u bytes of text"
3550 			" data, CRC 0x%08x\n", text_length,
3551 			cmd->data_crc);
3552 	}
3553 
3554 	cmd->iov_misc_count = iov_count;
3555 	cmd->tx_size = tx_size;
3556 
3557 	return 0;
3558 }
3559 
3560 void
3561 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3562 		    struct iscsi_reject *hdr)
3563 {
3564 	hdr->opcode		= ISCSI_OP_REJECT;
3565 	hdr->reason		= cmd->reject_reason;
3566 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3567 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3568 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3569 	cmd->stat_sn		= conn->stat_sn++;
3570 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3571 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3572 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3573 
3574 }
3575 EXPORT_SYMBOL(iscsit_build_reject);
3576 
3577 static int iscsit_send_reject(
3578 	struct iscsi_cmd *cmd,
3579 	struct iscsi_conn *conn)
3580 {
3581 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3582 	struct kvec *iov;
3583 	u32 iov_count = 0, tx_size;
3584 
3585 	iscsit_build_reject(cmd, conn, hdr);
3586 
3587 	iov = &cmd->iov_misc[0];
3588 	iov[iov_count].iov_base = cmd->pdu;
3589 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3590 	iov[iov_count].iov_base = cmd->buf_ptr;
3591 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3592 
3593 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3594 
3595 	if (conn->conn_ops->HeaderDigest) {
3596 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3597 
3598 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3599 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3600 
3601 		iov[0].iov_len += ISCSI_CRC_LEN;
3602 		tx_size += ISCSI_CRC_LEN;
3603 		pr_debug("Attaching CRC32 HeaderDigest for"
3604 			" REJECT PDU 0x%08x\n", *header_digest);
3605 	}
3606 
3607 	if (conn->conn_ops->DataDigest) {
3608 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->buf_ptr,
3609 				ISCSI_HDR_LEN, 0, NULL, (u8 *)&cmd->data_crc);
3610 
3611 		iov[iov_count].iov_base = &cmd->data_crc;
3612 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3613 		tx_size += ISCSI_CRC_LEN;
3614 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3615 				" PDU 0x%08x\n", cmd->data_crc);
3616 	}
3617 
3618 	cmd->iov_misc_count = iov_count;
3619 	cmd->tx_size = tx_size;
3620 
3621 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3622 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3623 
3624 	return 0;
3625 }
3626 
3627 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3628 {
3629 	struct iscsi_thread_set *ts = conn->thread_set;
3630 	int ord, cpu;
3631 	/*
3632 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3633 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3634 	 *
3635 	 * Here we use thread_id to determine which CPU that this
3636 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3637 	 * execute upon.
3638 	 */
3639 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3640 	for_each_online_cpu(cpu) {
3641 		if (ord-- == 0) {
3642 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3643 			return;
3644 		}
3645 	}
3646 	/*
3647 	 * This should never be reached..
3648 	 */
3649 	dump_stack();
3650 	cpumask_setall(conn->conn_cpumask);
3651 }
3652 
3653 static inline void iscsit_thread_check_cpumask(
3654 	struct iscsi_conn *conn,
3655 	struct task_struct *p,
3656 	int mode)
3657 {
3658 	char buf[128];
3659 	/*
3660 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3661 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3662 	 */
3663 	if (mode == 1) {
3664 		if (!conn->conn_tx_reset_cpumask)
3665 			return;
3666 		conn->conn_tx_reset_cpumask = 0;
3667 	} else {
3668 		if (!conn->conn_rx_reset_cpumask)
3669 			return;
3670 		conn->conn_rx_reset_cpumask = 0;
3671 	}
3672 	/*
3673 	 * Update the CPU mask for this single kthread so that
3674 	 * both TX and RX kthreads are scheduled to run on the
3675 	 * same CPU.
3676 	 */
3677 	memset(buf, 0, 128);
3678 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3679 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3680 }
3681 
3682 static int
3683 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3684 {
3685 	int ret;
3686 
3687 	switch (state) {
3688 	case ISTATE_SEND_R2T:
3689 		ret = iscsit_send_r2t(cmd, conn);
3690 		if (ret < 0)
3691 			goto err;
3692 		break;
3693 	case ISTATE_REMOVE:
3694 		spin_lock_bh(&conn->cmd_lock);
3695 		list_del(&cmd->i_conn_node);
3696 		spin_unlock_bh(&conn->cmd_lock);
3697 
3698 		iscsit_free_cmd(cmd, false);
3699 		break;
3700 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3701 		iscsit_mod_nopin_response_timer(conn);
3702 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3703 		if (ret < 0)
3704 			goto err;
3705 		break;
3706 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3707 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3708 		if (ret < 0)
3709 			goto err;
3710 		break;
3711 	default:
3712 		pr_err("Unknown Opcode: 0x%02x ITT:"
3713 		       " 0x%08x, i_state: %d on CID: %hu\n",
3714 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3715 		       conn->cid);
3716 		goto err;
3717 	}
3718 
3719 	return 0;
3720 
3721 err:
3722 	return -1;
3723 }
3724 
3725 static int
3726 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3727 {
3728 	struct iscsit_transport *t = conn->conn_transport;
3729 	struct iscsi_queue_req *qr;
3730 	struct iscsi_cmd *cmd;
3731 	u8 state;
3732 	int ret;
3733 
3734 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3735 		atomic_set(&conn->check_immediate_queue, 0);
3736 		cmd = qr->cmd;
3737 		state = qr->state;
3738 		kmem_cache_free(lio_qr_cache, qr);
3739 
3740 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3741 		if (ret < 0)
3742 			return ret;
3743 	}
3744 
3745 	return 0;
3746 }
3747 
3748 static int
3749 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3750 {
3751 	int ret;
3752 
3753 check_rsp_state:
3754 	switch (state) {
3755 	case ISTATE_SEND_DATAIN:
3756 		ret = iscsit_send_datain(cmd, conn);
3757 		if (ret < 0)
3758 			goto err;
3759 		else if (!ret)
3760 			/* more drs */
3761 			goto check_rsp_state;
3762 		else if (ret == 1) {
3763 			/* all done */
3764 			spin_lock_bh(&cmd->istate_lock);
3765 			cmd->i_state = ISTATE_SENT_STATUS;
3766 			spin_unlock_bh(&cmd->istate_lock);
3767 
3768 			if (atomic_read(&conn->check_immediate_queue))
3769 				return 1;
3770 
3771 			return 0;
3772 		} else if (ret == 2) {
3773 			/* Still must send status,
3774 			   SCF_TRANSPORT_TASK_SENSE was set */
3775 			spin_lock_bh(&cmd->istate_lock);
3776 			cmd->i_state = ISTATE_SEND_STATUS;
3777 			spin_unlock_bh(&cmd->istate_lock);
3778 			state = ISTATE_SEND_STATUS;
3779 			goto check_rsp_state;
3780 		}
3781 
3782 		break;
3783 	case ISTATE_SEND_STATUS:
3784 	case ISTATE_SEND_STATUS_RECOVERY:
3785 		ret = iscsit_send_response(cmd, conn);
3786 		break;
3787 	case ISTATE_SEND_LOGOUTRSP:
3788 		ret = iscsit_send_logout(cmd, conn);
3789 		break;
3790 	case ISTATE_SEND_ASYNCMSG:
3791 		ret = iscsit_send_conn_drop_async_message(
3792 			cmd, conn);
3793 		break;
3794 	case ISTATE_SEND_NOPIN:
3795 		ret = iscsit_send_nopin(cmd, conn);
3796 		break;
3797 	case ISTATE_SEND_REJECT:
3798 		ret = iscsit_send_reject(cmd, conn);
3799 		break;
3800 	case ISTATE_SEND_TASKMGTRSP:
3801 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3802 		if (ret != 0)
3803 			break;
3804 		ret = iscsit_tmr_post_handler(cmd, conn);
3805 		if (ret != 0)
3806 			iscsit_fall_back_to_erl0(conn->sess);
3807 		break;
3808 	case ISTATE_SEND_TEXTRSP:
3809 		ret = iscsit_send_text_rsp(cmd, conn);
3810 		break;
3811 	default:
3812 		pr_err("Unknown Opcode: 0x%02x ITT:"
3813 		       " 0x%08x, i_state: %d on CID: %hu\n",
3814 		       cmd->iscsi_opcode, cmd->init_task_tag,
3815 		       state, conn->cid);
3816 		goto err;
3817 	}
3818 	if (ret < 0)
3819 		goto err;
3820 
3821 	if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3822 		iscsit_tx_thread_wait_for_tcp(conn);
3823 		iscsit_unmap_iovec(cmd);
3824 		goto err;
3825 	}
3826 	iscsit_unmap_iovec(cmd);
3827 
3828 	switch (state) {
3829 	case ISTATE_SEND_LOGOUTRSP:
3830 		if (!iscsit_logout_post_handler(cmd, conn))
3831 			goto restart;
3832 		/* fall through */
3833 	case ISTATE_SEND_STATUS:
3834 	case ISTATE_SEND_ASYNCMSG:
3835 	case ISTATE_SEND_NOPIN:
3836 	case ISTATE_SEND_STATUS_RECOVERY:
3837 	case ISTATE_SEND_TEXTRSP:
3838 	case ISTATE_SEND_TASKMGTRSP:
3839 	case ISTATE_SEND_REJECT:
3840 		spin_lock_bh(&cmd->istate_lock);
3841 		cmd->i_state = ISTATE_SENT_STATUS;
3842 		spin_unlock_bh(&cmd->istate_lock);
3843 		break;
3844 	default:
3845 		pr_err("Unknown Opcode: 0x%02x ITT:"
3846 		       " 0x%08x, i_state: %d on CID: %hu\n",
3847 		       cmd->iscsi_opcode, cmd->init_task_tag,
3848 		       cmd->i_state, conn->cid);
3849 		goto err;
3850 	}
3851 
3852 	if (atomic_read(&conn->check_immediate_queue))
3853 		return 1;
3854 
3855 	return 0;
3856 
3857 err:
3858 	return -1;
3859 restart:
3860 	return -EAGAIN;
3861 }
3862 
3863 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3864 {
3865 	struct iscsit_transport *t = conn->conn_transport;
3866 	struct iscsi_queue_req *qr;
3867 	struct iscsi_cmd *cmd;
3868 	u8 state;
3869 	int ret;
3870 
3871 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3872 		cmd = qr->cmd;
3873 		state = qr->state;
3874 		kmem_cache_free(lio_qr_cache, qr);
3875 
3876 		ret = t->iscsit_response_queue(conn, cmd, state);
3877 		if (ret == 1 || ret < 0)
3878 			return ret;
3879 	}
3880 
3881 	return 0;
3882 }
3883 
3884 int iscsi_target_tx_thread(void *arg)
3885 {
3886 	int ret = 0;
3887 	struct iscsi_conn *conn;
3888 	struct iscsi_thread_set *ts = arg;
3889 	/*
3890 	 * Allow ourselves to be interrupted by SIGINT so that a
3891 	 * connection recovery / failure event can be triggered externally.
3892 	 */
3893 	allow_signal(SIGINT);
3894 
3895 restart:
3896 	conn = iscsi_tx_thread_pre_handler(ts);
3897 	if (!conn)
3898 		goto out;
3899 
3900 	ret = 0;
3901 
3902 	while (!kthread_should_stop()) {
3903 		/*
3904 		 * Ensure that both TX and RX per connection kthreads
3905 		 * are scheduled to run on the same CPU.
3906 		 */
3907 		iscsit_thread_check_cpumask(conn, current, 1);
3908 
3909 		wait_event_interruptible(conn->queues_wq,
3910 					 !iscsit_conn_all_queues_empty(conn) ||
3911 					 ts->status == ISCSI_THREAD_SET_RESET);
3912 
3913 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3914 		     signal_pending(current))
3915 			goto transport_err;
3916 
3917 get_immediate:
3918 		ret = iscsit_handle_immediate_queue(conn);
3919 		if (ret < 0)
3920 			goto transport_err;
3921 
3922 		ret = iscsit_handle_response_queue(conn);
3923 		if (ret == 1)
3924 			goto get_immediate;
3925 		else if (ret == -EAGAIN)
3926 			goto restart;
3927 		else if (ret < 0)
3928 			goto transport_err;
3929 	}
3930 
3931 transport_err:
3932 	iscsit_take_action_for_connection_exit(conn);
3933 	goto restart;
3934 out:
3935 	return 0;
3936 }
3937 
3938 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3939 {
3940 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3941 	struct iscsi_cmd *cmd;
3942 	int ret = 0;
3943 
3944 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3945 	case ISCSI_OP_SCSI_CMD:
3946 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3947 		if (!cmd)
3948 			goto reject;
3949 
3950 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3951 		break;
3952 	case ISCSI_OP_SCSI_DATA_OUT:
3953 		ret = iscsit_handle_data_out(conn, buf);
3954 		break;
3955 	case ISCSI_OP_NOOP_OUT:
3956 		cmd = NULL;
3957 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3958 			cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3959 			if (!cmd)
3960 				goto reject;
3961 		}
3962 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3963 		break;
3964 	case ISCSI_OP_SCSI_TMFUNC:
3965 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3966 		if (!cmd)
3967 			goto reject;
3968 
3969 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3970 		break;
3971 	case ISCSI_OP_TEXT:
3972 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3973 		if (!cmd)
3974 			goto reject;
3975 
3976 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3977 		break;
3978 	case ISCSI_OP_LOGOUT:
3979 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3980 		if (!cmd)
3981 			goto reject;
3982 
3983 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3984 		if (ret > 0)
3985 			wait_for_completion_timeout(&conn->conn_logout_comp,
3986 					SECONDS_FOR_LOGOUT_COMP * HZ);
3987 		break;
3988 	case ISCSI_OP_SNACK:
3989 		ret = iscsit_handle_snack(conn, buf);
3990 		break;
3991 	default:
3992 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3993 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3994 			pr_err("Cannot recover from unknown"
3995 			" opcode while ERL=0, closing iSCSI connection.\n");
3996 			return -1;
3997 		}
3998 		if (!conn->conn_ops->OFMarker) {
3999 			pr_err("Unable to recover from unknown"
4000 			" opcode while OFMarker=No, closing iSCSI"
4001 				" connection.\n");
4002 			return -1;
4003 		}
4004 		if (iscsit_recover_from_unknown_opcode(conn) < 0) {
4005 			pr_err("Unable to recover from unknown"
4006 				" opcode, closing iSCSI connection.\n");
4007 			return -1;
4008 		}
4009 		break;
4010 	}
4011 
4012 	return ret;
4013 reject:
4014 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4015 }
4016 
4017 int iscsi_target_rx_thread(void *arg)
4018 {
4019 	int ret;
4020 	u8 buffer[ISCSI_HDR_LEN], opcode;
4021 	u32 checksum = 0, digest = 0;
4022 	struct iscsi_conn *conn = NULL;
4023 	struct iscsi_thread_set *ts = arg;
4024 	struct kvec iov;
4025 	/*
4026 	 * Allow ourselves to be interrupted by SIGINT so that a
4027 	 * connection recovery / failure event can be triggered externally.
4028 	 */
4029 	allow_signal(SIGINT);
4030 
4031 restart:
4032 	conn = iscsi_rx_thread_pre_handler(ts);
4033 	if (!conn)
4034 		goto out;
4035 
4036 	if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
4037 		struct completion comp;
4038 		int rc;
4039 
4040 		init_completion(&comp);
4041 		rc = wait_for_completion_interruptible(&comp);
4042 		if (rc < 0)
4043 			goto transport_err;
4044 
4045 		goto out;
4046 	}
4047 
4048 	while (!kthread_should_stop()) {
4049 		/*
4050 		 * Ensure that both TX and RX per connection kthreads
4051 		 * are scheduled to run on the same CPU.
4052 		 */
4053 		iscsit_thread_check_cpumask(conn, current, 0);
4054 
4055 		memset(buffer, 0, ISCSI_HDR_LEN);
4056 		memset(&iov, 0, sizeof(struct kvec));
4057 
4058 		iov.iov_base	= buffer;
4059 		iov.iov_len	= ISCSI_HDR_LEN;
4060 
4061 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4062 		if (ret != ISCSI_HDR_LEN) {
4063 			iscsit_rx_thread_wait_for_tcp(conn);
4064 			goto transport_err;
4065 		}
4066 
4067 		if (conn->conn_ops->HeaderDigest) {
4068 			iov.iov_base	= &digest;
4069 			iov.iov_len	= ISCSI_CRC_LEN;
4070 
4071 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4072 			if (ret != ISCSI_CRC_LEN) {
4073 				iscsit_rx_thread_wait_for_tcp(conn);
4074 				goto transport_err;
4075 			}
4076 
4077 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
4078 					buffer, ISCSI_HDR_LEN,
4079 					0, NULL, (u8 *)&checksum);
4080 
4081 			if (digest != checksum) {
4082 				pr_err("HeaderDigest CRC32C failed,"
4083 					" received 0x%08x, computed 0x%08x\n",
4084 					digest, checksum);
4085 				/*
4086 				 * Set the PDU to 0xff so it will intentionally
4087 				 * hit default in the switch below.
4088 				 */
4089 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4090 				spin_lock_bh(&conn->sess->session_stats_lock);
4091 				conn->sess->conn_digest_errors++;
4092 				spin_unlock_bh(&conn->sess->session_stats_lock);
4093 			} else {
4094 				pr_debug("Got HeaderDigest CRC32C"
4095 						" 0x%08x\n", checksum);
4096 			}
4097 		}
4098 
4099 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4100 			goto transport_err;
4101 
4102 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4103 
4104 		if (conn->sess->sess_ops->SessionType &&
4105 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4106 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4107 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4108 			" while in Discovery Session, rejecting.\n", opcode);
4109 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4110 					  buffer);
4111 			goto transport_err;
4112 		}
4113 
4114 		ret = iscsi_target_rx_opcode(conn, buffer);
4115 		if (ret < 0)
4116 			goto transport_err;
4117 	}
4118 
4119 transport_err:
4120 	if (!signal_pending(current))
4121 		atomic_set(&conn->transport_failed, 1);
4122 	iscsit_take_action_for_connection_exit(conn);
4123 	goto restart;
4124 out:
4125 	return 0;
4126 }
4127 
4128 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4129 {
4130 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4131 	struct iscsi_session *sess = conn->sess;
4132 	/*
4133 	 * We expect this function to only ever be called from either RX or TX
4134 	 * thread context via iscsit_close_connection() once the other context
4135 	 * has been reset -> returned sleeping pre-handler state.
4136 	 */
4137 	spin_lock_bh(&conn->cmd_lock);
4138 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
4139 
4140 		list_del(&cmd->i_conn_node);
4141 		spin_unlock_bh(&conn->cmd_lock);
4142 
4143 		iscsit_increment_maxcmdsn(cmd, sess);
4144 
4145 		iscsit_free_cmd(cmd, true);
4146 
4147 		spin_lock_bh(&conn->cmd_lock);
4148 	}
4149 	spin_unlock_bh(&conn->cmd_lock);
4150 }
4151 
4152 static void iscsit_stop_timers_for_cmds(
4153 	struct iscsi_conn *conn)
4154 {
4155 	struct iscsi_cmd *cmd;
4156 
4157 	spin_lock_bh(&conn->cmd_lock);
4158 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4159 		if (cmd->data_direction == DMA_TO_DEVICE)
4160 			iscsit_stop_dataout_timer(cmd);
4161 	}
4162 	spin_unlock_bh(&conn->cmd_lock);
4163 }
4164 
4165 int iscsit_close_connection(
4166 	struct iscsi_conn *conn)
4167 {
4168 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4169 	struct iscsi_session	*sess = conn->sess;
4170 
4171 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4172 		" %u\n", conn->cid, sess->sid);
4173 	/*
4174 	 * Always up conn_logout_comp just in case the RX Thread is sleeping
4175 	 * and the logout response never got sent because the connection
4176 	 * failed.
4177 	 */
4178 	complete(&conn->conn_logout_comp);
4179 
4180 	iscsi_release_thread_set(conn);
4181 
4182 	iscsit_stop_timers_for_cmds(conn);
4183 	iscsit_stop_nopin_response_timer(conn);
4184 	iscsit_stop_nopin_timer(conn);
4185 	iscsit_free_queue_reqs_for_conn(conn);
4186 
4187 	/*
4188 	 * During Connection recovery drop unacknowledged out of order
4189 	 * commands for this connection, and prepare the other commands
4190 	 * for realligence.
4191 	 *
4192 	 * During normal operation clear the out of order commands (but
4193 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4194 	 * struct iscsi_cmds.
4195 	 */
4196 	if (atomic_read(&conn->connection_recovery)) {
4197 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4198 		iscsit_prepare_cmds_for_realligance(conn);
4199 	} else {
4200 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4201 		iscsit_release_commands_from_conn(conn);
4202 	}
4203 
4204 	/*
4205 	 * Handle decrementing session or connection usage count if
4206 	 * a logout response was not able to be sent because the
4207 	 * connection failed.  Fall back to Session Recovery here.
4208 	 */
4209 	if (atomic_read(&conn->conn_logout_remove)) {
4210 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4211 			iscsit_dec_conn_usage_count(conn);
4212 			iscsit_dec_session_usage_count(sess);
4213 		}
4214 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4215 			iscsit_dec_conn_usage_count(conn);
4216 
4217 		atomic_set(&conn->conn_logout_remove, 0);
4218 		atomic_set(&sess->session_reinstatement, 0);
4219 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4220 	}
4221 
4222 	spin_lock_bh(&sess->conn_lock);
4223 	list_del(&conn->conn_list);
4224 
4225 	/*
4226 	 * Attempt to let the Initiator know this connection failed by
4227 	 * sending an Connection Dropped Async Message on another
4228 	 * active connection.
4229 	 */
4230 	if (atomic_read(&conn->connection_recovery))
4231 		iscsit_build_conn_drop_async_message(conn);
4232 
4233 	spin_unlock_bh(&sess->conn_lock);
4234 
4235 	/*
4236 	 * If connection reinstatement is being performed on this connection,
4237 	 * up the connection reinstatement semaphore that is being blocked on
4238 	 * in iscsit_cause_connection_reinstatement().
4239 	 */
4240 	spin_lock_bh(&conn->state_lock);
4241 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4242 		spin_unlock_bh(&conn->state_lock);
4243 		complete(&conn->conn_wait_comp);
4244 		wait_for_completion(&conn->conn_post_wait_comp);
4245 		spin_lock_bh(&conn->state_lock);
4246 	}
4247 
4248 	/*
4249 	 * If connection reinstatement is being performed on this connection
4250 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4251 	 * connection wait rcfr semaphore that is being blocked on
4252 	 * an iscsit_connection_reinstatement_rcfr().
4253 	 */
4254 	if (atomic_read(&conn->connection_wait_rcfr)) {
4255 		spin_unlock_bh(&conn->state_lock);
4256 		complete(&conn->conn_wait_rcfr_comp);
4257 		wait_for_completion(&conn->conn_post_wait_comp);
4258 		spin_lock_bh(&conn->state_lock);
4259 	}
4260 	atomic_set(&conn->connection_reinstatement, 1);
4261 	spin_unlock_bh(&conn->state_lock);
4262 
4263 	/*
4264 	 * If any other processes are accessing this connection pointer we
4265 	 * must wait until they have completed.
4266 	 */
4267 	iscsit_check_conn_usage_count(conn);
4268 
4269 	if (conn->conn_rx_hash.tfm)
4270 		crypto_free_hash(conn->conn_rx_hash.tfm);
4271 	if (conn->conn_tx_hash.tfm)
4272 		crypto_free_hash(conn->conn_tx_hash.tfm);
4273 
4274 	if (conn->conn_cpumask)
4275 		free_cpumask_var(conn->conn_cpumask);
4276 
4277 	kfree(conn->conn_ops);
4278 	conn->conn_ops = NULL;
4279 
4280 	if (conn->sock)
4281 		sock_release(conn->sock);
4282 
4283 	if (conn->conn_transport->iscsit_free_conn)
4284 		conn->conn_transport->iscsit_free_conn(conn);
4285 
4286 	iscsit_put_transport(conn->conn_transport);
4287 
4288 	conn->thread_set = NULL;
4289 
4290 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4291 	conn->conn_state = TARG_CONN_STATE_FREE;
4292 	kfree(conn);
4293 
4294 	spin_lock_bh(&sess->conn_lock);
4295 	atomic_dec(&sess->nconn);
4296 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4297 		" %s\n", atomic_read(&sess->nconn),
4298 		sess->sess_ops->InitiatorName);
4299 	/*
4300 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4301 	 * Session that they all fail.
4302 	 */
4303 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4304 	     !atomic_read(&sess->session_logout))
4305 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4306 
4307 	/*
4308 	 * If this was not the last connection in the session, and we are
4309 	 * performing session reinstatement or falling back to ERL=0, call
4310 	 * iscsit_stop_session() without sleeping to shutdown the other
4311 	 * active connections.
4312 	 */
4313 	if (atomic_read(&sess->nconn)) {
4314 		if (!atomic_read(&sess->session_reinstatement) &&
4315 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4316 			spin_unlock_bh(&sess->conn_lock);
4317 			return 0;
4318 		}
4319 		if (!atomic_read(&sess->session_stop_active)) {
4320 			atomic_set(&sess->session_stop_active, 1);
4321 			spin_unlock_bh(&sess->conn_lock);
4322 			iscsit_stop_session(sess, 0, 0);
4323 			return 0;
4324 		}
4325 		spin_unlock_bh(&sess->conn_lock);
4326 		return 0;
4327 	}
4328 
4329 	/*
4330 	 * If this was the last connection in the session and one of the
4331 	 * following is occurring:
4332 	 *
4333 	 * Session Reinstatement is not being performed, and are falling back
4334 	 * to ERL=0 call iscsit_close_session().
4335 	 *
4336 	 * Session Logout was requested.  iscsit_close_session() will be called
4337 	 * elsewhere.
4338 	 *
4339 	 * Session Continuation is not being performed, start the Time2Retain
4340 	 * handler and check if sleep_on_sess_wait_sem is active.
4341 	 */
4342 	if (!atomic_read(&sess->session_reinstatement) &&
4343 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4344 		spin_unlock_bh(&sess->conn_lock);
4345 		target_put_session(sess->se_sess);
4346 
4347 		return 0;
4348 	} else if (atomic_read(&sess->session_logout)) {
4349 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4350 		sess->session_state = TARG_SESS_STATE_FREE;
4351 		spin_unlock_bh(&sess->conn_lock);
4352 
4353 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4354 			complete(&sess->session_wait_comp);
4355 
4356 		return 0;
4357 	} else {
4358 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4359 		sess->session_state = TARG_SESS_STATE_FAILED;
4360 
4361 		if (!atomic_read(&sess->session_continuation)) {
4362 			spin_unlock_bh(&sess->conn_lock);
4363 			iscsit_start_time2retain_handler(sess);
4364 		} else
4365 			spin_unlock_bh(&sess->conn_lock);
4366 
4367 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4368 			complete(&sess->session_wait_comp);
4369 
4370 		return 0;
4371 	}
4372 	spin_unlock_bh(&sess->conn_lock);
4373 
4374 	return 0;
4375 }
4376 
4377 int iscsit_close_session(struct iscsi_session *sess)
4378 {
4379 	struct iscsi_portal_group *tpg = ISCSI_TPG_S(sess);
4380 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4381 
4382 	if (atomic_read(&sess->nconn)) {
4383 		pr_err("%d connection(s) still exist for iSCSI session"
4384 			" to %s\n", atomic_read(&sess->nconn),
4385 			sess->sess_ops->InitiatorName);
4386 		BUG();
4387 	}
4388 
4389 	spin_lock_bh(&se_tpg->session_lock);
4390 	atomic_set(&sess->session_logout, 1);
4391 	atomic_set(&sess->session_reinstatement, 1);
4392 	iscsit_stop_time2retain_timer(sess);
4393 	spin_unlock_bh(&se_tpg->session_lock);
4394 
4395 	/*
4396 	 * transport_deregister_session_configfs() will clear the
4397 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4398 	 * can be setting it again with __transport_register_session() in
4399 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4400 	 * completes in iscsi_np context.
4401 	 */
4402 	transport_deregister_session_configfs(sess->se_sess);
4403 
4404 	/*
4405 	 * If any other processes are accessing this session pointer we must
4406 	 * wait until they have completed.  If we are in an interrupt (the
4407 	 * time2retain handler) and contain and active session usage count we
4408 	 * restart the timer and exit.
4409 	 */
4410 	if (!in_interrupt()) {
4411 		if (iscsit_check_session_usage_count(sess) == 1)
4412 			iscsit_stop_session(sess, 1, 1);
4413 	} else {
4414 		if (iscsit_check_session_usage_count(sess) == 2) {
4415 			atomic_set(&sess->session_logout, 0);
4416 			iscsit_start_time2retain_handler(sess);
4417 			return 0;
4418 		}
4419 	}
4420 
4421 	transport_deregister_session(sess->se_sess);
4422 
4423 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4424 		iscsit_free_connection_recovery_entires(sess);
4425 
4426 	iscsit_free_all_ooo_cmdsns(sess);
4427 
4428 	spin_lock_bh(&se_tpg->session_lock);
4429 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4430 	sess->session_state = TARG_SESS_STATE_FREE;
4431 	pr_debug("Released iSCSI session from node: %s\n",
4432 			sess->sess_ops->InitiatorName);
4433 	tpg->nsessions--;
4434 	if (tpg->tpg_tiqn)
4435 		tpg->tpg_tiqn->tiqn_nsessions--;
4436 
4437 	pr_debug("Decremented number of active iSCSI Sessions on"
4438 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4439 
4440 	spin_lock(&sess_idr_lock);
4441 	idr_remove(&sess_idr, sess->session_index);
4442 	spin_unlock(&sess_idr_lock);
4443 
4444 	kfree(sess->sess_ops);
4445 	sess->sess_ops = NULL;
4446 	spin_unlock_bh(&se_tpg->session_lock);
4447 
4448 	kfree(sess);
4449 	return 0;
4450 }
4451 
4452 static void iscsit_logout_post_handler_closesession(
4453 	struct iscsi_conn *conn)
4454 {
4455 	struct iscsi_session *sess = conn->sess;
4456 
4457 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4458 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4459 
4460 	atomic_set(&conn->conn_logout_remove, 0);
4461 	complete(&conn->conn_logout_comp);
4462 
4463 	iscsit_dec_conn_usage_count(conn);
4464 	iscsit_stop_session(sess, 1, 1);
4465 	iscsit_dec_session_usage_count(sess);
4466 	target_put_session(sess->se_sess);
4467 }
4468 
4469 static void iscsit_logout_post_handler_samecid(
4470 	struct iscsi_conn *conn)
4471 {
4472 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4473 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4474 
4475 	atomic_set(&conn->conn_logout_remove, 0);
4476 	complete(&conn->conn_logout_comp);
4477 
4478 	iscsit_cause_connection_reinstatement(conn, 1);
4479 	iscsit_dec_conn_usage_count(conn);
4480 }
4481 
4482 static void iscsit_logout_post_handler_diffcid(
4483 	struct iscsi_conn *conn,
4484 	u16 cid)
4485 {
4486 	struct iscsi_conn *l_conn;
4487 	struct iscsi_session *sess = conn->sess;
4488 
4489 	if (!sess)
4490 		return;
4491 
4492 	spin_lock_bh(&sess->conn_lock);
4493 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4494 		if (l_conn->cid == cid) {
4495 			iscsit_inc_conn_usage_count(l_conn);
4496 			break;
4497 		}
4498 	}
4499 	spin_unlock_bh(&sess->conn_lock);
4500 
4501 	if (!l_conn)
4502 		return;
4503 
4504 	if (l_conn->sock)
4505 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4506 
4507 	spin_lock_bh(&l_conn->state_lock);
4508 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4509 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4510 	spin_unlock_bh(&l_conn->state_lock);
4511 
4512 	iscsit_cause_connection_reinstatement(l_conn, 1);
4513 	iscsit_dec_conn_usage_count(l_conn);
4514 }
4515 
4516 /*
4517  *	Return of 0 causes the TX thread to restart.
4518  */
4519 int iscsit_logout_post_handler(
4520 	struct iscsi_cmd *cmd,
4521 	struct iscsi_conn *conn)
4522 {
4523 	int ret = 0;
4524 
4525 	switch (cmd->logout_reason) {
4526 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4527 		switch (cmd->logout_response) {
4528 		case ISCSI_LOGOUT_SUCCESS:
4529 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4530 		default:
4531 			iscsit_logout_post_handler_closesession(conn);
4532 			break;
4533 		}
4534 		ret = 0;
4535 		break;
4536 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4537 		if (conn->cid == cmd->logout_cid) {
4538 			switch (cmd->logout_response) {
4539 			case ISCSI_LOGOUT_SUCCESS:
4540 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4541 			default:
4542 				iscsit_logout_post_handler_samecid(conn);
4543 				break;
4544 			}
4545 			ret = 0;
4546 		} else {
4547 			switch (cmd->logout_response) {
4548 			case ISCSI_LOGOUT_SUCCESS:
4549 				iscsit_logout_post_handler_diffcid(conn,
4550 					cmd->logout_cid);
4551 				break;
4552 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4553 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4554 			default:
4555 				break;
4556 			}
4557 			ret = 1;
4558 		}
4559 		break;
4560 	case ISCSI_LOGOUT_REASON_RECOVERY:
4561 		switch (cmd->logout_response) {
4562 		case ISCSI_LOGOUT_SUCCESS:
4563 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4564 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4565 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4566 		default:
4567 			break;
4568 		}
4569 		ret = 1;
4570 		break;
4571 	default:
4572 		break;
4573 
4574 	}
4575 	return ret;
4576 }
4577 EXPORT_SYMBOL(iscsit_logout_post_handler);
4578 
4579 void iscsit_fail_session(struct iscsi_session *sess)
4580 {
4581 	struct iscsi_conn *conn;
4582 
4583 	spin_lock_bh(&sess->conn_lock);
4584 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4585 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4586 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4587 	}
4588 	spin_unlock_bh(&sess->conn_lock);
4589 
4590 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4591 	sess->session_state = TARG_SESS_STATE_FAILED;
4592 }
4593 
4594 int iscsit_free_session(struct iscsi_session *sess)
4595 {
4596 	u16 conn_count = atomic_read(&sess->nconn);
4597 	struct iscsi_conn *conn, *conn_tmp = NULL;
4598 	int is_last;
4599 
4600 	spin_lock_bh(&sess->conn_lock);
4601 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4602 
4603 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4604 			conn_list) {
4605 		if (conn_count == 0)
4606 			break;
4607 
4608 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4609 			is_last = 1;
4610 		} else {
4611 			iscsit_inc_conn_usage_count(conn_tmp);
4612 			is_last = 0;
4613 		}
4614 		iscsit_inc_conn_usage_count(conn);
4615 
4616 		spin_unlock_bh(&sess->conn_lock);
4617 		iscsit_cause_connection_reinstatement(conn, 1);
4618 		spin_lock_bh(&sess->conn_lock);
4619 
4620 		iscsit_dec_conn_usage_count(conn);
4621 		if (is_last == 0)
4622 			iscsit_dec_conn_usage_count(conn_tmp);
4623 
4624 		conn_count--;
4625 	}
4626 
4627 	if (atomic_read(&sess->nconn)) {
4628 		spin_unlock_bh(&sess->conn_lock);
4629 		wait_for_completion(&sess->session_wait_comp);
4630 	} else
4631 		spin_unlock_bh(&sess->conn_lock);
4632 
4633 	target_put_session(sess->se_sess);
4634 	return 0;
4635 }
4636 
4637 void iscsit_stop_session(
4638 	struct iscsi_session *sess,
4639 	int session_sleep,
4640 	int connection_sleep)
4641 {
4642 	u16 conn_count = atomic_read(&sess->nconn);
4643 	struct iscsi_conn *conn, *conn_tmp = NULL;
4644 	int is_last;
4645 
4646 	spin_lock_bh(&sess->conn_lock);
4647 	if (session_sleep)
4648 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4649 
4650 	if (connection_sleep) {
4651 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4652 				conn_list) {
4653 			if (conn_count == 0)
4654 				break;
4655 
4656 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4657 				is_last = 1;
4658 			} else {
4659 				iscsit_inc_conn_usage_count(conn_tmp);
4660 				is_last = 0;
4661 			}
4662 			iscsit_inc_conn_usage_count(conn);
4663 
4664 			spin_unlock_bh(&sess->conn_lock);
4665 			iscsit_cause_connection_reinstatement(conn, 1);
4666 			spin_lock_bh(&sess->conn_lock);
4667 
4668 			iscsit_dec_conn_usage_count(conn);
4669 			if (is_last == 0)
4670 				iscsit_dec_conn_usage_count(conn_tmp);
4671 			conn_count--;
4672 		}
4673 	} else {
4674 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4675 			iscsit_cause_connection_reinstatement(conn, 0);
4676 	}
4677 
4678 	if (session_sleep && atomic_read(&sess->nconn)) {
4679 		spin_unlock_bh(&sess->conn_lock);
4680 		wait_for_completion(&sess->session_wait_comp);
4681 	} else
4682 		spin_unlock_bh(&sess->conn_lock);
4683 }
4684 
4685 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4686 {
4687 	struct iscsi_session *sess;
4688 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4689 	struct se_session *se_sess, *se_sess_tmp;
4690 	int session_count = 0;
4691 
4692 	spin_lock_bh(&se_tpg->session_lock);
4693 	if (tpg->nsessions && !force) {
4694 		spin_unlock_bh(&se_tpg->session_lock);
4695 		return -1;
4696 	}
4697 
4698 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4699 			sess_list) {
4700 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4701 
4702 		spin_lock(&sess->conn_lock);
4703 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4704 		    atomic_read(&sess->session_logout) ||
4705 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4706 			spin_unlock(&sess->conn_lock);
4707 			continue;
4708 		}
4709 		atomic_set(&sess->session_reinstatement, 1);
4710 		spin_unlock(&sess->conn_lock);
4711 		spin_unlock_bh(&se_tpg->session_lock);
4712 
4713 		iscsit_free_session(sess);
4714 		spin_lock_bh(&se_tpg->session_lock);
4715 
4716 		session_count++;
4717 	}
4718 	spin_unlock_bh(&se_tpg->session_lock);
4719 
4720 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4721 			" Group: %hu\n", session_count, tpg->tpgt);
4722 	return 0;
4723 }
4724 
4725 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4726 MODULE_VERSION("4.1.x");
4727 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4728 MODULE_LICENSE("GPL");
4729 
4730 module_init(iscsi_target_init_module);
4731 module_exit(iscsi_target_cleanup_module);
4732