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 	LIST_HEAD(ack_list);
757 	struct iscsi_cmd *cmd, *cmd_p;
758 
759 	conn->exp_statsn = exp_statsn;
760 
761 	if (conn->sess->sess_ops->RDMAExtensions)
762 		return;
763 
764 	spin_lock_bh(&conn->cmd_lock);
765 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
766 		spin_lock(&cmd->istate_lock);
767 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
768 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
769 			cmd->i_state = ISTATE_REMOVE;
770 			spin_unlock(&cmd->istate_lock);
771 			list_move_tail(&cmd->i_conn_node, &ack_list);
772 			continue;
773 		}
774 		spin_unlock(&cmd->istate_lock);
775 	}
776 	spin_unlock_bh(&conn->cmd_lock);
777 
778 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
779 		list_del(&cmd->i_conn_node);
780 		iscsit_free_cmd(cmd, false);
781 	}
782 }
783 
784 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
785 {
786 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
787 
788 	iov_count += ISCSI_IOV_DATA_BUFFER;
789 
790 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
791 	if (!cmd->iov_data) {
792 		pr_err("Unable to allocate cmd->iov_data\n");
793 		return -ENOMEM;
794 	}
795 
796 	cmd->orig_iov_data_count = iov_count;
797 	return 0;
798 }
799 
800 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
801 			  unsigned char *buf)
802 {
803 	int data_direction, payload_length;
804 	struct iscsi_scsi_req *hdr;
805 	int iscsi_task_attr;
806 	int sam_task_attr;
807 
808 	spin_lock_bh(&conn->sess->session_stats_lock);
809 	conn->sess->cmd_pdus++;
810 	if (conn->sess->se_sess->se_node_acl) {
811 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
812 		conn->sess->se_sess->se_node_acl->num_cmds++;
813 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
814 	}
815 	spin_unlock_bh(&conn->sess->session_stats_lock);
816 
817 	hdr			= (struct iscsi_scsi_req *) buf;
818 	payload_length		= ntoh24(hdr->dlength);
819 
820 	/* FIXME; Add checks for AdditionalHeaderSegment */
821 
822 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
823 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
824 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
825 				" not set. Bad iSCSI Initiator.\n");
826 		return iscsit_add_reject_cmd(cmd,
827 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
828 	}
829 
830 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
831 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
832 		/*
833 		 * Vmware ESX v3.0 uses a modified Cisco Initiator (v3.4.2)
834 		 * that adds support for RESERVE/RELEASE.  There is a bug
835 		 * add with this new functionality that sets R/W bits when
836 		 * neither CDB carries any READ or WRITE datapayloads.
837 		 */
838 		if ((hdr->cdb[0] == 0x16) || (hdr->cdb[0] == 0x17)) {
839 			hdr->flags &= ~ISCSI_FLAG_CMD_READ;
840 			hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
841 			goto done;
842 		}
843 
844 		pr_err("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
845 			" set when Expected Data Transfer Length is 0 for"
846 			" CDB: 0x%02x. Bad iSCSI Initiator.\n", hdr->cdb[0]);
847 		return iscsit_add_reject_cmd(cmd,
848 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
849 	}
850 done:
851 
852 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
853 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
854 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
855 			" MUST be set if Expected Data Transfer Length is not 0."
856 			" Bad iSCSI Initiator\n");
857 		return iscsit_add_reject_cmd(cmd,
858 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
859 	}
860 
861 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
862 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
863 		pr_err("Bidirectional operations not supported!\n");
864 		return iscsit_add_reject_cmd(cmd,
865 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
866 	}
867 
868 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
869 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
870 				" Scsi Command PDU.\n");
871 		return iscsit_add_reject_cmd(cmd,
872 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
873 	}
874 
875 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
876 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
877 			" protocol error.\n", payload_length);
878 		return iscsit_add_reject_cmd(cmd,
879 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
880 	}
881 
882 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
883 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
884 		pr_err("Expected Data Transfer Length and Length of"
885 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
886 			" bit is not set protocol error\n");
887 		return iscsit_add_reject_cmd(cmd,
888 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
889 	}
890 
891 	if (payload_length > be32_to_cpu(hdr->data_length)) {
892 		pr_err("DataSegmentLength: %u is greater than"
893 			" EDTL: %u, protocol error.\n", payload_length,
894 				hdr->data_length);
895 		return iscsit_add_reject_cmd(cmd,
896 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
897 	}
898 
899 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
900 		pr_err("DataSegmentLength: %u is greater than"
901 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
902 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
903 		return iscsit_add_reject_cmd(cmd,
904 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
905 	}
906 
907 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
908 		pr_err("DataSegmentLength: %u is greater than"
909 			" FirstBurstLength: %u, protocol error.\n",
910 			payload_length, conn->sess->sess_ops->FirstBurstLength);
911 		return iscsit_add_reject_cmd(cmd,
912 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
913 	}
914 
915 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
916 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
917 			  DMA_NONE;
918 
919 	cmd->data_direction = data_direction;
920 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
921 	/*
922 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
923 	 */
924 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
925 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
926 		sam_task_attr = MSG_SIMPLE_TAG;
927 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
928 		sam_task_attr = MSG_ORDERED_TAG;
929 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
930 		sam_task_attr = MSG_HEAD_TAG;
931 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
932 		sam_task_attr = MSG_ACA_TAG;
933 	else {
934 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
935 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
936 		sam_task_attr = MSG_SIMPLE_TAG;
937 	}
938 
939 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
940 	cmd->i_state		= ISTATE_NEW_CMD;
941 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
942 	cmd->immediate_data	= (payload_length) ? 1 : 0;
943 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
944 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
945 	if (cmd->unsolicited_data)
946 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
947 
948 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
949 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
950 		spin_lock_bh(&conn->sess->ttt_lock);
951 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
952 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
953 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
954 		spin_unlock_bh(&conn->sess->ttt_lock);
955 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
956 		cmd->targ_xfer_tag = 0xFFFFFFFF;
957 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
958 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
959 	cmd->first_burst_len	= payload_length;
960 
961 	if (!conn->sess->sess_ops->RDMAExtensions &&
962 	     cmd->data_direction == DMA_FROM_DEVICE) {
963 		struct iscsi_datain_req *dr;
964 
965 		dr = iscsit_allocate_datain_req();
966 		if (!dr)
967 			return iscsit_add_reject_cmd(cmd,
968 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
969 
970 		iscsit_attach_datain_req(cmd, dr);
971 	}
972 
973 	/*
974 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
975 	 */
976 	transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
977 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
978 			cmd->data_direction, sam_task_attr,
979 			cmd->sense_buffer + 2);
980 
981 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
982 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
983 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
984 		conn->cid);
985 
986 	target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
987 
988 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
989 						     scsilun_to_int(&hdr->lun));
990 	if (cmd->sense_reason)
991 		goto attach_cmd;
992 
993 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
994 	if (cmd->sense_reason) {
995 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
996 			return iscsit_add_reject_cmd(cmd,
997 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
998 		}
999 
1000 		goto attach_cmd;
1001 	}
1002 
1003 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1004 		return iscsit_add_reject_cmd(cmd,
1005 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1006 	}
1007 
1008 attach_cmd:
1009 	spin_lock_bh(&conn->cmd_lock);
1010 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1011 	spin_unlock_bh(&conn->cmd_lock);
1012 	/*
1013 	 * Check if we need to delay processing because of ALUA
1014 	 * Active/NonOptimized primary access state..
1015 	 */
1016 	core_alua_check_nonop_delay(&cmd->se_cmd);
1017 
1018 	return 0;
1019 }
1020 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1021 
1022 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1023 {
1024 	iscsit_set_dataout_sequence_values(cmd);
1025 
1026 	spin_lock_bh(&cmd->dataout_timeout_lock);
1027 	iscsit_start_dataout_timer(cmd, cmd->conn);
1028 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1029 }
1030 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1031 
1032 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1033 			    struct iscsi_scsi_req *hdr)
1034 {
1035 	int cmdsn_ret = 0;
1036 	/*
1037 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1038 	 * the Immediate Bit is not set, and no Immediate
1039 	 * Data is attached.
1040 	 *
1041 	 * A PDU/CmdSN carrying Immediate Data can only
1042 	 * be processed after the DataCRC has passed.
1043 	 * If the DataCRC fails, the CmdSN MUST NOT
1044 	 * be acknowledged. (See below)
1045 	 */
1046 	if (!cmd->immediate_data) {
1047 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1048 					(unsigned char *)hdr, hdr->cmdsn);
1049 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1050 			return -1;
1051 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1052 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1053 			return 0;
1054 		}
1055 	}
1056 
1057 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1058 
1059 	/*
1060 	 * If no Immediate Data is attached, it's OK to return now.
1061 	 */
1062 	if (!cmd->immediate_data) {
1063 		if (!cmd->sense_reason && cmd->unsolicited_data)
1064 			iscsit_set_unsoliticed_dataout(cmd);
1065 		if (!cmd->sense_reason)
1066 			return 0;
1067 
1068 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1069 		return 0;
1070 	}
1071 
1072 	/*
1073 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1074 	 * execution.  These exceptions are processed in CmdSN order using
1075 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1076 	 */
1077 	if (cmd->sense_reason) {
1078 		if (cmd->reject_reason)
1079 			return 0;
1080 
1081 		return 1;
1082 	}
1083 	/*
1084 	 * Call directly into transport_generic_new_cmd() to perform
1085 	 * the backend memory allocation.
1086 	 */
1087 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1088 	if (cmd->sense_reason)
1089 		return 1;
1090 
1091 	return 0;
1092 }
1093 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1094 
1095 static int
1096 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1097 			  bool dump_payload)
1098 {
1099 	struct iscsi_conn *conn = cmd->conn;
1100 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1101 	/*
1102 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1103 	 */
1104 	if (dump_payload == true)
1105 		goto after_immediate_data;
1106 
1107 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1108 					cmd->first_burst_len);
1109 after_immediate_data:
1110 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1111 		/*
1112 		 * A PDU/CmdSN carrying Immediate Data passed
1113 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1114 		 * Immediate Bit is not set.
1115 		 */
1116 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1117 					(unsigned char *)hdr, hdr->cmdsn);
1118 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1119 			return -1;
1120 
1121 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1122 			int rc;
1123 
1124 			rc = iscsit_dump_data_payload(cmd->conn,
1125 						      cmd->first_burst_len, 1);
1126 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1127 			return rc;
1128 		} else if (cmd->unsolicited_data)
1129 			iscsit_set_unsoliticed_dataout(cmd);
1130 
1131 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1132 		/*
1133 		 * Immediate Data failed DataCRC and ERL>=1,
1134 		 * silently drop this PDU and let the initiator
1135 		 * plug the CmdSN gap.
1136 		 *
1137 		 * FIXME: Send Unsolicited NOPIN with reserved
1138 		 * TTT here to help the initiator figure out
1139 		 * the missing CmdSN, although they should be
1140 		 * intelligent enough to determine the missing
1141 		 * CmdSN and issue a retry to plug the sequence.
1142 		 */
1143 		cmd->i_state = ISTATE_REMOVE;
1144 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1145 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1146 		return -1;
1147 
1148 	return 0;
1149 }
1150 
1151 static int
1152 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1153 			   unsigned char *buf)
1154 {
1155 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1156 	int rc, immed_data;
1157 	bool dump_payload = false;
1158 
1159 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1160 	if (rc < 0)
1161 		return 0;
1162 	/*
1163 	 * Allocation iovecs needed for struct socket operations for
1164 	 * traditional iSCSI block I/O.
1165 	 */
1166 	if (iscsit_allocate_iovecs(cmd) < 0) {
1167 		return iscsit_add_reject_cmd(cmd,
1168 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1169 	}
1170 	immed_data = cmd->immediate_data;
1171 
1172 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1173 	if (rc < 0)
1174 		return rc;
1175 	else if (rc > 0)
1176 		dump_payload = true;
1177 
1178 	if (!immed_data)
1179 		return 0;
1180 
1181 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1182 }
1183 
1184 static u32 iscsit_do_crypto_hash_sg(
1185 	struct hash_desc *hash,
1186 	struct iscsi_cmd *cmd,
1187 	u32 data_offset,
1188 	u32 data_length,
1189 	u32 padding,
1190 	u8 *pad_bytes)
1191 {
1192 	u32 data_crc;
1193 	u32 i;
1194 	struct scatterlist *sg;
1195 	unsigned int page_off;
1196 
1197 	crypto_hash_init(hash);
1198 
1199 	sg = cmd->first_data_sg;
1200 	page_off = cmd->first_data_sg_off;
1201 
1202 	i = 0;
1203 	while (data_length) {
1204 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1205 
1206 		crypto_hash_update(hash, &sg[i], cur_len);
1207 
1208 		data_length -= cur_len;
1209 		page_off = 0;
1210 		i++;
1211 	}
1212 
1213 	if (padding) {
1214 		struct scatterlist pad_sg;
1215 
1216 		sg_init_one(&pad_sg, pad_bytes, padding);
1217 		crypto_hash_update(hash, &pad_sg, padding);
1218 	}
1219 	crypto_hash_final(hash, (u8 *) &data_crc);
1220 
1221 	return data_crc;
1222 }
1223 
1224 static void iscsit_do_crypto_hash_buf(
1225 	struct hash_desc *hash,
1226 	const void *buf,
1227 	u32 payload_length,
1228 	u32 padding,
1229 	u8 *pad_bytes,
1230 	u8 *data_crc)
1231 {
1232 	struct scatterlist sg;
1233 
1234 	crypto_hash_init(hash);
1235 
1236 	sg_init_one(&sg, buf, payload_length);
1237 	crypto_hash_update(hash, &sg, payload_length);
1238 
1239 	if (padding) {
1240 		sg_init_one(&sg, pad_bytes, padding);
1241 		crypto_hash_update(hash, &sg, padding);
1242 	}
1243 	crypto_hash_final(hash, data_crc);
1244 }
1245 
1246 int
1247 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1248 			  struct iscsi_cmd **out_cmd)
1249 {
1250 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1251 	struct iscsi_cmd *cmd = NULL;
1252 	struct se_cmd *se_cmd;
1253 	u32 payload_length = ntoh24(hdr->dlength);
1254 	int rc;
1255 
1256 	if (!payload_length) {
1257 		pr_err("DataOUT payload is ZERO, protocol error.\n");
1258 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1259 					 buf);
1260 	}
1261 
1262 	/* iSCSI write */
1263 	spin_lock_bh(&conn->sess->session_stats_lock);
1264 	conn->sess->rx_data_octets += payload_length;
1265 	if (conn->sess->se_sess->se_node_acl) {
1266 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
1267 		conn->sess->se_sess->se_node_acl->write_bytes += payload_length;
1268 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
1269 	}
1270 	spin_unlock_bh(&conn->sess->session_stats_lock);
1271 
1272 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1273 		pr_err("DataSegmentLength: %u is greater than"
1274 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1275 			conn->conn_ops->MaxXmitDataSegmentLength);
1276 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1277 					 buf);
1278 	}
1279 
1280 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1281 			payload_length);
1282 	if (!cmd)
1283 		return 0;
1284 
1285 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1286 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1287 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1288 		payload_length, conn->cid);
1289 
1290 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1291 		pr_err("Command ITT: 0x%08x received DataOUT after"
1292 			" last DataOUT received, dumping payload\n",
1293 			cmd->init_task_tag);
1294 		return iscsit_dump_data_payload(conn, payload_length, 1);
1295 	}
1296 
1297 	if (cmd->data_direction != DMA_TO_DEVICE) {
1298 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1299 			" NON-WRITE command.\n", cmd->init_task_tag);
1300 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
1301 	}
1302 	se_cmd = &cmd->se_cmd;
1303 	iscsit_mod_dataout_timer(cmd);
1304 
1305 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1306 		pr_err("DataOut Offset: %u, Length %u greater than"
1307 			" iSCSI Command EDTL %u, protocol error.\n",
1308 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1309 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1310 	}
1311 
1312 	if (cmd->unsolicited_data) {
1313 		int dump_unsolicited_data = 0;
1314 
1315 		if (conn->sess->sess_ops->InitialR2T) {
1316 			pr_err("Received unexpected unsolicited data"
1317 				" while InitialR2T=Yes, protocol error.\n");
1318 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1319 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1320 			return -1;
1321 		}
1322 		/*
1323 		 * Special case for dealing with Unsolicited DataOUT
1324 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1325 		 * failures;
1326 		 */
1327 
1328 		/* Something's amiss if we're not in WRITE_PENDING state... */
1329 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1330 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1331 			dump_unsolicited_data = 1;
1332 
1333 		if (dump_unsolicited_data) {
1334 			/*
1335 			 * Check if a delayed TASK_ABORTED status needs to
1336 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1337 			 * received with the unsolicitied data out.
1338 			 */
1339 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1340 				iscsit_stop_dataout_timer(cmd);
1341 
1342 			transport_check_aborted_status(se_cmd,
1343 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1344 			return iscsit_dump_data_payload(conn, payload_length, 1);
1345 		}
1346 	} else {
1347 		/*
1348 		 * For the normal solicited data path:
1349 		 *
1350 		 * Check for a delayed TASK_ABORTED status and dump any
1351 		 * incoming data out payload if one exists.  Also, when the
1352 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1353 		 * data out sequence, we decrement outstanding_r2ts.  Once
1354 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1355 		 * TASK_ABORTED status.
1356 		 */
1357 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1358 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1359 				if (--cmd->outstanding_r2ts < 1) {
1360 					iscsit_stop_dataout_timer(cmd);
1361 					transport_check_aborted_status(
1362 							se_cmd, 1);
1363 				}
1364 
1365 			return iscsit_dump_data_payload(conn, payload_length, 1);
1366 		}
1367 	}
1368 	/*
1369 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1370 	 * within-command recovery checks before receiving the payload.
1371 	 */
1372 	rc = iscsit_check_pre_dataout(cmd, buf);
1373 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1374 		return 0;
1375 	else if (rc == DATAOUT_CANNOT_RECOVER)
1376 		return -1;
1377 
1378 	*out_cmd = cmd;
1379 	return 0;
1380 }
1381 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1382 
1383 static int
1384 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1385 		   struct iscsi_data *hdr)
1386 {
1387 	struct kvec *iov;
1388 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1389 	u32 payload_length = ntoh24(hdr->dlength);
1390 	int iov_ret, data_crc_failed = 0;
1391 
1392 	rx_size += payload_length;
1393 	iov = &cmd->iov_data[0];
1394 
1395 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1396 				   payload_length);
1397 	if (iov_ret < 0)
1398 		return -1;
1399 
1400 	iov_count += iov_ret;
1401 
1402 	padding = ((-payload_length) & 3);
1403 	if (padding != 0) {
1404 		iov[iov_count].iov_base	= cmd->pad_bytes;
1405 		iov[iov_count++].iov_len = padding;
1406 		rx_size += padding;
1407 		pr_debug("Receiving %u padding bytes.\n", padding);
1408 	}
1409 
1410 	if (conn->conn_ops->DataDigest) {
1411 		iov[iov_count].iov_base = &checksum;
1412 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1413 		rx_size += ISCSI_CRC_LEN;
1414 	}
1415 
1416 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1417 
1418 	iscsit_unmap_iovec(cmd);
1419 
1420 	if (rx_got != rx_size)
1421 		return -1;
1422 
1423 	if (conn->conn_ops->DataDigest) {
1424 		u32 data_crc;
1425 
1426 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1427 						    be32_to_cpu(hdr->offset),
1428 						    payload_length, padding,
1429 						    cmd->pad_bytes);
1430 
1431 		if (checksum != data_crc) {
1432 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1433 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1434 				" does not match computed 0x%08x\n",
1435 				hdr->itt, hdr->offset, payload_length,
1436 				hdr->datasn, checksum, data_crc);
1437 			data_crc_failed = 1;
1438 		} else {
1439 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1440 				" %u bytes of Data Out\n", checksum,
1441 				payload_length);
1442 		}
1443 	}
1444 
1445 	return data_crc_failed;
1446 }
1447 
1448 int
1449 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1450 			     bool data_crc_failed)
1451 {
1452 	struct iscsi_conn *conn = cmd->conn;
1453 	int rc, ooo_cmdsn;
1454 	/*
1455 	 * Increment post receive data and CRC values or perform
1456 	 * within-command recovery.
1457 	 */
1458 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1459 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1460 		return 0;
1461 	else if (rc == DATAOUT_SEND_R2T) {
1462 		iscsit_set_dataout_sequence_values(cmd);
1463 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1464 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1465 		/*
1466 		 * Handle extra special case for out of order
1467 		 * Unsolicited Data Out.
1468 		 */
1469 		spin_lock_bh(&cmd->istate_lock);
1470 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1471 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1472 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1473 		spin_unlock_bh(&cmd->istate_lock);
1474 
1475 		iscsit_stop_dataout_timer(cmd);
1476 		if (ooo_cmdsn)
1477 			return 0;
1478 		target_execute_cmd(&cmd->se_cmd);
1479 		return 0;
1480 	} else /* DATAOUT_CANNOT_RECOVER */
1481 		return -1;
1482 
1483 	return 0;
1484 }
1485 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1486 
1487 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1488 {
1489 	struct iscsi_cmd *cmd;
1490 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1491 	int rc;
1492 	bool data_crc_failed = false;
1493 
1494 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1495 	if (rc < 0)
1496 		return 0;
1497 	else if (!cmd)
1498 		return 0;
1499 
1500 	rc = iscsit_get_dataout(conn, cmd, hdr);
1501 	if (rc < 0)
1502 		return rc;
1503 	else if (rc > 0)
1504 		data_crc_failed = true;
1505 
1506 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1507 }
1508 
1509 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1510 			 struct iscsi_nopout *hdr)
1511 {
1512 	u32 payload_length = ntoh24(hdr->dlength);
1513 
1514 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1515 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1516 			" not set, protocol error.\n");
1517 		if (!cmd)
1518 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1519 						 (unsigned char *)hdr);
1520 
1521 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1522 					 (unsigned char *)hdr);
1523 	}
1524 
1525 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1526 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1527 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1528 			" error.\n", payload_length,
1529 			conn->conn_ops->MaxXmitDataSegmentLength);
1530 		if (!cmd)
1531 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1532 						 (unsigned char *)hdr);
1533 
1534 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1535 					 (unsigned char *)hdr);
1536 	}
1537 
1538 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1539 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1540 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1541 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1542 		payload_length);
1543 	/*
1544 	 * This is not a response to a Unsolicited NopIN, which means
1545 	 * it can either be a NOPOUT ping request (with a valid ITT),
1546 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1547 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1548 	 * can contain ping data.
1549 	 */
1550 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1551 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1552 		cmd->i_state		= ISTATE_SEND_NOPIN;
1553 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1554 						1 : 0);
1555 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1556 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1557 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1558 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1559 		cmd->data_direction	= DMA_NONE;
1560 	}
1561 
1562 	return 0;
1563 }
1564 EXPORT_SYMBOL(iscsit_setup_nop_out);
1565 
1566 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1567 			   struct iscsi_nopout *hdr)
1568 {
1569 	struct iscsi_cmd *cmd_p = NULL;
1570 	int cmdsn_ret = 0;
1571 	/*
1572 	 * Initiator is expecting a NopIN ping reply..
1573 	 */
1574 	if (hdr->itt != RESERVED_ITT) {
1575 		BUG_ON(!cmd);
1576 
1577 		spin_lock_bh(&conn->cmd_lock);
1578 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1579 		spin_unlock_bh(&conn->cmd_lock);
1580 
1581 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1582 
1583 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1584 			iscsit_add_cmd_to_response_queue(cmd, conn,
1585 							 cmd->i_state);
1586 			return 0;
1587 		}
1588 
1589 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1590 				(unsigned char *)hdr, hdr->cmdsn);
1591                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1592 			return 0;
1593 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1594 			return -1;
1595 
1596 		return 0;
1597 	}
1598 	/*
1599 	 * This was a response to a unsolicited NOPIN ping.
1600 	 */
1601 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1602 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1603 		if (!cmd_p)
1604 			return -EINVAL;
1605 
1606 		iscsit_stop_nopin_response_timer(conn);
1607 
1608 		cmd_p->i_state = ISTATE_REMOVE;
1609 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1610 
1611 		iscsit_start_nopin_timer(conn);
1612 		return 0;
1613 	}
1614 	/*
1615 	 * Otherwise, initiator is not expecting a NOPIN is response.
1616 	 * Just ignore for now.
1617 	 */
1618         return 0;
1619 }
1620 EXPORT_SYMBOL(iscsit_process_nop_out);
1621 
1622 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1623 				 unsigned char *buf)
1624 {
1625 	unsigned char *ping_data = NULL;
1626 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1627 	struct kvec *iov = NULL;
1628 	u32 payload_length = ntoh24(hdr->dlength);
1629 	int ret;
1630 
1631 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1632 	if (ret < 0)
1633 		return 0;
1634 	/*
1635 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1636 	 */
1637 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1638 		u32 checksum, data_crc, padding = 0;
1639 		int niov = 0, rx_got, rx_size = payload_length;
1640 
1641 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1642 		if (!ping_data) {
1643 			pr_err("Unable to allocate memory for"
1644 				" NOPOUT ping data.\n");
1645 			ret = -1;
1646 			goto out;
1647 		}
1648 
1649 		iov = &cmd->iov_misc[0];
1650 		iov[niov].iov_base	= ping_data;
1651 		iov[niov++].iov_len	= payload_length;
1652 
1653 		padding = ((-payload_length) & 3);
1654 		if (padding != 0) {
1655 			pr_debug("Receiving %u additional bytes"
1656 				" for padding.\n", padding);
1657 			iov[niov].iov_base	= &cmd->pad_bytes;
1658 			iov[niov++].iov_len	= padding;
1659 			rx_size += padding;
1660 		}
1661 		if (conn->conn_ops->DataDigest) {
1662 			iov[niov].iov_base	= &checksum;
1663 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1664 			rx_size += ISCSI_CRC_LEN;
1665 		}
1666 
1667 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1668 		if (rx_got != rx_size) {
1669 			ret = -1;
1670 			goto out;
1671 		}
1672 
1673 		if (conn->conn_ops->DataDigest) {
1674 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1675 					ping_data, payload_length,
1676 					padding, cmd->pad_bytes,
1677 					(u8 *)&data_crc);
1678 
1679 			if (checksum != data_crc) {
1680 				pr_err("Ping data CRC32C DataDigest"
1681 				" 0x%08x does not match computed 0x%08x\n",
1682 					checksum, data_crc);
1683 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1684 					pr_err("Unable to recover from"
1685 					" NOPOUT Ping DataCRC failure while in"
1686 						" ERL=0.\n");
1687 					ret = -1;
1688 					goto out;
1689 				} else {
1690 					/*
1691 					 * Silently drop this PDU and let the
1692 					 * initiator plug the CmdSN gap.
1693 					 */
1694 					pr_debug("Dropping NOPOUT"
1695 					" Command CmdSN: 0x%08x due to"
1696 					" DataCRC error.\n", hdr->cmdsn);
1697 					ret = 0;
1698 					goto out;
1699 				}
1700 			} else {
1701 				pr_debug("Got CRC32C DataDigest"
1702 				" 0x%08x for %u bytes of ping data.\n",
1703 					checksum, payload_length);
1704 			}
1705 		}
1706 
1707 		ping_data[payload_length] = '\0';
1708 		/*
1709 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1710 		 */
1711 		cmd->buf_ptr = ping_data;
1712 		cmd->buf_ptr_size = payload_length;
1713 
1714 		pr_debug("Got %u bytes of NOPOUT ping"
1715 			" data.\n", payload_length);
1716 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1717 	}
1718 
1719 	return iscsit_process_nop_out(conn, cmd, hdr);
1720 out:
1721 	if (cmd)
1722 		iscsit_free_cmd(cmd, false);
1723 
1724 	kfree(ping_data);
1725 	return ret;
1726 }
1727 
1728 int
1729 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1730 			   unsigned char *buf)
1731 {
1732 	struct se_tmr_req *se_tmr;
1733 	struct iscsi_tmr_req *tmr_req;
1734 	struct iscsi_tm *hdr;
1735 	int out_of_order_cmdsn = 0, ret;
1736 	bool sess_ref = false;
1737 	u8 function;
1738 
1739 	hdr			= (struct iscsi_tm *) buf;
1740 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1741 	function = hdr->flags;
1742 
1743 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1744 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1745 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1746 		hdr->rtt, hdr->refcmdsn, conn->cid);
1747 
1748 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1749 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1750 	     hdr->rtt != RESERVED_ITT)) {
1751 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1752 		hdr->rtt = RESERVED_ITT;
1753 	}
1754 
1755 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1756 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1757 		pr_err("Task Management Request TASK_REASSIGN not"
1758 			" issued as immediate command, bad iSCSI Initiator"
1759 				"implementation\n");
1760 		return iscsit_add_reject_cmd(cmd,
1761 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1762 	}
1763 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1764 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1765 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1766 
1767 	cmd->data_direction = DMA_NONE;
1768 
1769 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1770 	if (!cmd->tmr_req) {
1771 		pr_err("Unable to allocate memory for"
1772 			" Task Management command!\n");
1773 		return iscsit_add_reject_cmd(cmd,
1774 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1775 					     buf);
1776 	}
1777 
1778 	/*
1779 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1780 	 * LIO-Target $FABRIC_MOD
1781 	 */
1782 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1783 
1784 		u8 tcm_function;
1785 		int ret;
1786 
1787 		transport_init_se_cmd(&cmd->se_cmd,
1788 				      &lio_target_fabric_configfs->tf_ops,
1789 				      conn->sess->se_sess, 0, DMA_NONE,
1790 				      MSG_SIMPLE_TAG, cmd->sense_buffer + 2);
1791 
1792 		target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
1793 		sess_ref = true;
1794 
1795 		switch (function) {
1796 		case ISCSI_TM_FUNC_ABORT_TASK:
1797 			tcm_function = TMR_ABORT_TASK;
1798 			break;
1799 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1800 			tcm_function = TMR_ABORT_TASK_SET;
1801 			break;
1802 		case ISCSI_TM_FUNC_CLEAR_ACA:
1803 			tcm_function = TMR_CLEAR_ACA;
1804 			break;
1805 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1806 			tcm_function = TMR_CLEAR_TASK_SET;
1807 			break;
1808 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1809 			tcm_function = TMR_LUN_RESET;
1810 			break;
1811 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1812 			tcm_function = TMR_TARGET_WARM_RESET;
1813 			break;
1814 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1815 			tcm_function = TMR_TARGET_COLD_RESET;
1816 			break;
1817 		default:
1818 			pr_err("Unknown iSCSI TMR Function:"
1819 			       " 0x%02x\n", function);
1820 			return iscsit_add_reject_cmd(cmd,
1821 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1822 		}
1823 
1824 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1825 					 tcm_function, GFP_KERNEL);
1826 		if (ret < 0)
1827 			return iscsit_add_reject_cmd(cmd,
1828 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1829 
1830 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1831 	}
1832 
1833 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1834 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1835 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1836 	cmd->init_task_tag	= hdr->itt;
1837 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1838 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1839 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1840 	se_tmr			= cmd->se_cmd.se_tmr_req;
1841 	tmr_req			= cmd->tmr_req;
1842 	/*
1843 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1844 	 */
1845 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1846 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1847 					       scsilun_to_int(&hdr->lun));
1848 		if (ret < 0) {
1849 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1850 			goto attach;
1851 		}
1852 	}
1853 
1854 	switch (function) {
1855 	case ISCSI_TM_FUNC_ABORT_TASK:
1856 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1857 		if (se_tmr->response)
1858 			goto attach;
1859 		break;
1860 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1861 	case ISCSI_TM_FUNC_CLEAR_ACA:
1862 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1863 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1864 		break;
1865 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1866 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1867 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1868 			goto attach;
1869 		}
1870 		break;
1871 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1872 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1873 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1874 			goto attach;
1875 		}
1876 		break;
1877 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1878 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1879 		/*
1880 		 * Perform sanity checks on the ExpDataSN only if the
1881 		 * TASK_REASSIGN was successful.
1882 		 */
1883 		if (se_tmr->response)
1884 			break;
1885 
1886 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1887 			return iscsit_add_reject_cmd(cmd,
1888 					ISCSI_REASON_BOOKMARK_INVALID, buf);
1889 		break;
1890 	default:
1891 		pr_err("Unknown TMR function: 0x%02x, protocol"
1892 			" error.\n", function);
1893 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1894 		goto attach;
1895 	}
1896 
1897 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1898 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1899 		se_tmr->call_transport = 1;
1900 attach:
1901 	spin_lock_bh(&conn->cmd_lock);
1902 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1903 	spin_unlock_bh(&conn->cmd_lock);
1904 
1905 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1906 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1907 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1908 			out_of_order_cmdsn = 1;
1909 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1910 			return 0;
1911 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1912 			return -1;
1913 	}
1914 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1915 
1916 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1917 		return 0;
1918 	/*
1919 	 * Found the referenced task, send to transport for processing.
1920 	 */
1921 	if (se_tmr->call_transport)
1922 		return transport_generic_handle_tmr(&cmd->se_cmd);
1923 
1924 	/*
1925 	 * Could not find the referenced LUN, task, or Task Management
1926 	 * command not authorized or supported.  Change state and
1927 	 * let the tx_thread send the response.
1928 	 *
1929 	 * For connection recovery, this is also the default action for
1930 	 * TMR TASK_REASSIGN.
1931 	 */
1932 	if (sess_ref) {
1933 		pr_debug("Handle TMR, using sess_ref=true check\n");
1934 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1935 	}
1936 
1937 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1938 	return 0;
1939 }
1940 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
1941 
1942 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1943 int
1944 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1945 		      struct iscsi_text *hdr)
1946 {
1947 	u32 payload_length = ntoh24(hdr->dlength);
1948 
1949 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1950 		pr_err("Unable to accept text parameter length: %u"
1951 			"greater than MaxXmitDataSegmentLength %u.\n",
1952 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1953 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1954 					 (unsigned char *)hdr);
1955 	}
1956 
1957 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1958 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1959 		hdr->exp_statsn, payload_length);
1960 
1961 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1962 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1963 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1964 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
1965 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1966 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1967 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1968 	cmd->data_direction	= DMA_NONE;
1969 
1970 	return 0;
1971 }
1972 EXPORT_SYMBOL(iscsit_setup_text_cmd);
1973 
1974 int
1975 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1976 			struct iscsi_text *hdr)
1977 {
1978 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
1979 	int cmdsn_ret;
1980 
1981 	if (!text_in) {
1982 		pr_err("Unable to locate text_in buffer for sendtargets"
1983 		       " discovery\n");
1984 		goto reject;
1985 	}
1986 	if (strncmp("SendTargets", text_in, 11) != 0) {
1987 		pr_err("Received Text Data that is not"
1988 			" SendTargets, cannot continue.\n");
1989 		goto reject;
1990 	}
1991 	text_ptr = strchr(text_in, '=');
1992 	if (!text_ptr) {
1993 		pr_err("No \"=\" separator found in Text Data,"
1994 			"  cannot continue.\n");
1995 		goto reject;
1996 	}
1997 	if (!strncmp("=All", text_ptr, 4)) {
1998 		cmd->cmd_flags |= IFC_SENDTARGETS_ALL;
1999 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2000 		   !strncmp("=eui.", text_ptr, 5)) {
2001 		cmd->cmd_flags |= IFC_SENDTARGETS_SINGLE;
2002 	} else {
2003 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2004 		goto reject;
2005 	}
2006 
2007 	spin_lock_bh(&conn->cmd_lock);
2008 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2009 	spin_unlock_bh(&conn->cmd_lock);
2010 
2011 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2012 
2013 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2014 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2015 				(unsigned char *)hdr, hdr->cmdsn);
2016 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2017 			return -1;
2018 
2019 		return 0;
2020 	}
2021 
2022 	return iscsit_execute_cmd(cmd, 0);
2023 
2024 reject:
2025 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2026 				 (unsigned char *)hdr);
2027 }
2028 EXPORT_SYMBOL(iscsit_process_text_cmd);
2029 
2030 static int
2031 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2032 		       unsigned char *buf)
2033 {
2034 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2035 	char *text_in = NULL;
2036 	u32 payload_length = ntoh24(hdr->dlength);
2037 	int rx_size, rc;
2038 
2039 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2040 	if (rc < 0)
2041 		return 0;
2042 
2043 	rx_size = payload_length;
2044 	if (payload_length) {
2045 		u32 checksum = 0, data_crc = 0;
2046 		u32 padding = 0, pad_bytes = 0;
2047 		int niov = 0, rx_got;
2048 		struct kvec iov[3];
2049 
2050 		text_in = kzalloc(payload_length, GFP_KERNEL);
2051 		if (!text_in) {
2052 			pr_err("Unable to allocate memory for"
2053 				" incoming text parameters\n");
2054 			goto reject;
2055 		}
2056 		cmd->text_in_ptr = text_in;
2057 
2058 		memset(iov, 0, 3 * sizeof(struct kvec));
2059 		iov[niov].iov_base	= text_in;
2060 		iov[niov++].iov_len	= payload_length;
2061 
2062 		padding = ((-payload_length) & 3);
2063 		if (padding != 0) {
2064 			iov[niov].iov_base = &pad_bytes;
2065 			iov[niov++].iov_len  = padding;
2066 			rx_size += padding;
2067 			pr_debug("Receiving %u additional bytes"
2068 					" for padding.\n", padding);
2069 		}
2070 		if (conn->conn_ops->DataDigest) {
2071 			iov[niov].iov_base	= &checksum;
2072 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2073 			rx_size += ISCSI_CRC_LEN;
2074 		}
2075 
2076 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2077 		if (rx_got != rx_size)
2078 			goto reject;
2079 
2080 		if (conn->conn_ops->DataDigest) {
2081 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
2082 					text_in, payload_length,
2083 					padding, (u8 *)&pad_bytes,
2084 					(u8 *)&data_crc);
2085 
2086 			if (checksum != data_crc) {
2087 				pr_err("Text data CRC32C DataDigest"
2088 					" 0x%08x does not match computed"
2089 					" 0x%08x\n", checksum, data_crc);
2090 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2091 					pr_err("Unable to recover from"
2092 					" Text Data digest failure while in"
2093 						" ERL=0.\n");
2094 					goto reject;
2095 				} else {
2096 					/*
2097 					 * Silently drop this PDU and let the
2098 					 * initiator plug the CmdSN gap.
2099 					 */
2100 					pr_debug("Dropping Text"
2101 					" Command CmdSN: 0x%08x due to"
2102 					" DataCRC error.\n", hdr->cmdsn);
2103 					kfree(text_in);
2104 					return 0;
2105 				}
2106 			} else {
2107 				pr_debug("Got CRC32C DataDigest"
2108 					" 0x%08x for %u bytes of text data.\n",
2109 						checksum, payload_length);
2110 			}
2111 		}
2112 		text_in[payload_length - 1] = '\0';
2113 		pr_debug("Successfully read %d bytes of text"
2114 				" data.\n", payload_length);
2115 	}
2116 
2117 	return iscsit_process_text_cmd(conn, cmd, hdr);
2118 
2119 reject:
2120 	kfree(cmd->text_in_ptr);
2121 	cmd->text_in_ptr = NULL;
2122 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2123 }
2124 EXPORT_SYMBOL(iscsit_handle_text_cmd);
2125 
2126 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2127 {
2128 	struct iscsi_conn *conn_p;
2129 	struct iscsi_session *sess = conn->sess;
2130 
2131 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2132 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2133 
2134 	atomic_set(&sess->session_logout, 1);
2135 	atomic_set(&conn->conn_logout_remove, 1);
2136 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2137 
2138 	iscsit_inc_conn_usage_count(conn);
2139 	iscsit_inc_session_usage_count(sess);
2140 
2141 	spin_lock_bh(&sess->conn_lock);
2142 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2143 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2144 			continue;
2145 
2146 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2147 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2148 	}
2149 	spin_unlock_bh(&sess->conn_lock);
2150 
2151 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2152 
2153 	return 0;
2154 }
2155 
2156 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2157 {
2158 	struct iscsi_conn *l_conn;
2159 	struct iscsi_session *sess = conn->sess;
2160 
2161 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2162 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2163 
2164 	/*
2165 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2166 	 * can arrive on a connection with a differing CID.
2167 	 */
2168 	if (conn->cid == cmd->logout_cid) {
2169 		spin_lock_bh(&conn->state_lock);
2170 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2171 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2172 
2173 		atomic_set(&conn->conn_logout_remove, 1);
2174 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2175 		iscsit_inc_conn_usage_count(conn);
2176 
2177 		spin_unlock_bh(&conn->state_lock);
2178 	} else {
2179 		/*
2180 		 * Handle all different cid CLOSECONNECTION requests in
2181 		 * iscsit_logout_post_handler_diffcid() as to give enough
2182 		 * time for any non immediate command's CmdSN to be
2183 		 * acknowledged on the connection in question.
2184 		 *
2185 		 * Here we simply make sure the CID is still around.
2186 		 */
2187 		l_conn = iscsit_get_conn_from_cid(sess,
2188 				cmd->logout_cid);
2189 		if (!l_conn) {
2190 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2191 			iscsit_add_cmd_to_response_queue(cmd, conn,
2192 					cmd->i_state);
2193 			return 0;
2194 		}
2195 
2196 		iscsit_dec_conn_usage_count(l_conn);
2197 	}
2198 
2199 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2200 
2201 	return 0;
2202 }
2203 
2204 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2205 {
2206 	struct iscsi_session *sess = conn->sess;
2207 
2208 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2209 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2210 
2211 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2212 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2213 			" while ERL!=2.\n");
2214 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2215 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2216 		return 0;
2217 	}
2218 
2219 	if (conn->cid == cmd->logout_cid) {
2220 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2221 			" with CID: %hu on CID: %hu, implementation error.\n",
2222 				cmd->logout_cid, conn->cid);
2223 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2224 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2225 		return 0;
2226 	}
2227 
2228 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2229 
2230 	return 0;
2231 }
2232 
2233 int
2234 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2235 			unsigned char *buf)
2236 {
2237 	int cmdsn_ret, logout_remove = 0;
2238 	u8 reason_code = 0;
2239 	struct iscsi_logout *hdr;
2240 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2241 
2242 	hdr			= (struct iscsi_logout *) buf;
2243 	reason_code		= (hdr->flags & 0x7f);
2244 
2245 	if (tiqn) {
2246 		spin_lock(&tiqn->logout_stats.lock);
2247 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2248 			tiqn->logout_stats.normal_logouts++;
2249 		else
2250 			tiqn->logout_stats.abnormal_logouts++;
2251 		spin_unlock(&tiqn->logout_stats.lock);
2252 	}
2253 
2254 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2255 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2256 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2257 		hdr->cid, conn->cid);
2258 
2259 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2260 		pr_err("Received logout request on connection that"
2261 			" is not in logged in state, ignoring request.\n");
2262 		iscsit_free_cmd(cmd, false);
2263 		return 0;
2264 	}
2265 
2266 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2267 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2268 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2269 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2270 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2271 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2272 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2273 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2274 	cmd->logout_reason      = reason_code;
2275 	cmd->data_direction     = DMA_NONE;
2276 
2277 	/*
2278 	 * We need to sleep in these cases (by returning 1) until the Logout
2279 	 * Response gets sent in the tx thread.
2280 	 */
2281 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2282 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2283 	    be16_to_cpu(hdr->cid) == conn->cid))
2284 		logout_remove = 1;
2285 
2286 	spin_lock_bh(&conn->cmd_lock);
2287 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2288 	spin_unlock_bh(&conn->cmd_lock);
2289 
2290 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2291 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2292 
2293 	/*
2294 	 * Immediate commands are executed, well, immediately.
2295 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2296 	 */
2297 	if (cmd->immediate_cmd) {
2298 		int ret = iscsit_execute_cmd(cmd, 0);
2299 
2300 		if (ret < 0)
2301 			return ret;
2302 	} else {
2303 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2304 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2305 			logout_remove = 0;
2306 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2307 			return -1;
2308 	}
2309 
2310 	return logout_remove;
2311 }
2312 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2313 
2314 static int iscsit_handle_snack(
2315 	struct iscsi_conn *conn,
2316 	unsigned char *buf)
2317 {
2318 	struct iscsi_snack *hdr;
2319 
2320 	hdr			= (struct iscsi_snack *) buf;
2321 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2322 
2323 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2324 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2325 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2326 			hdr->begrun, hdr->runlength, conn->cid);
2327 
2328 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2329 		pr_err("Initiator sent SNACK request while in"
2330 			" ErrorRecoveryLevel=0.\n");
2331 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2332 					 buf);
2333 	}
2334 	/*
2335 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2336 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2337 	 */
2338 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2339 	case 0:
2340 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2341 			hdr->itt,
2342 			be32_to_cpu(hdr->ttt),
2343 			be32_to_cpu(hdr->begrun),
2344 			be32_to_cpu(hdr->runlength));
2345 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2346 		return iscsit_handle_status_snack(conn, hdr->itt,
2347 			be32_to_cpu(hdr->ttt),
2348 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2349 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2350 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2351 			be32_to_cpu(hdr->begrun),
2352 			be32_to_cpu(hdr->runlength));
2353 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2354 		/* FIXME: Support R-Data SNACK */
2355 		pr_err("R-Data SNACK Not Supported.\n");
2356 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2357 					 buf);
2358 	default:
2359 		pr_err("Unknown SNACK type 0x%02x, protocol"
2360 			" error.\n", hdr->flags & 0x0f);
2361 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2362 					 buf);
2363 	}
2364 
2365 	return 0;
2366 }
2367 
2368 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2369 {
2370 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2371 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2372 		wait_for_completion_interruptible_timeout(
2373 					&conn->rx_half_close_comp,
2374 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2375 	}
2376 }
2377 
2378 static int iscsit_handle_immediate_data(
2379 	struct iscsi_cmd *cmd,
2380 	struct iscsi_scsi_req *hdr,
2381 	u32 length)
2382 {
2383 	int iov_ret, rx_got = 0, rx_size = 0;
2384 	u32 checksum, iov_count = 0, padding = 0;
2385 	struct iscsi_conn *conn = cmd->conn;
2386 	struct kvec *iov;
2387 
2388 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2389 	if (iov_ret < 0)
2390 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2391 
2392 	rx_size = length;
2393 	iov_count = iov_ret;
2394 	iov = &cmd->iov_data[0];
2395 
2396 	padding = ((-length) & 3);
2397 	if (padding != 0) {
2398 		iov[iov_count].iov_base	= cmd->pad_bytes;
2399 		iov[iov_count++].iov_len = padding;
2400 		rx_size += padding;
2401 	}
2402 
2403 	if (conn->conn_ops->DataDigest) {
2404 		iov[iov_count].iov_base		= &checksum;
2405 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2406 		rx_size += ISCSI_CRC_LEN;
2407 	}
2408 
2409 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2410 
2411 	iscsit_unmap_iovec(cmd);
2412 
2413 	if (rx_got != rx_size) {
2414 		iscsit_rx_thread_wait_for_tcp(conn);
2415 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2416 	}
2417 
2418 	if (conn->conn_ops->DataDigest) {
2419 		u32 data_crc;
2420 
2421 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2422 						    cmd->write_data_done, length, padding,
2423 						    cmd->pad_bytes);
2424 
2425 		if (checksum != data_crc) {
2426 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2427 				" does not match computed 0x%08x\n", checksum,
2428 				data_crc);
2429 
2430 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2431 				pr_err("Unable to recover from"
2432 					" Immediate Data digest failure while"
2433 					" in ERL=0.\n");
2434 				iscsit_reject_cmd(cmd,
2435 						ISCSI_REASON_DATA_DIGEST_ERROR,
2436 						(unsigned char *)hdr);
2437 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2438 			} else {
2439 				iscsit_reject_cmd(cmd,
2440 						ISCSI_REASON_DATA_DIGEST_ERROR,
2441 						(unsigned char *)hdr);
2442 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2443 			}
2444 		} else {
2445 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2446 				" %u bytes of Immediate Data\n", checksum,
2447 				length);
2448 		}
2449 	}
2450 
2451 	cmd->write_data_done += length;
2452 
2453 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2454 		spin_lock_bh(&cmd->istate_lock);
2455 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2456 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2457 		spin_unlock_bh(&cmd->istate_lock);
2458 	}
2459 
2460 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2461 }
2462 
2463 /*
2464  *	Called with sess->conn_lock held.
2465  */
2466 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2467 	with active network interface */
2468 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2469 {
2470 	struct iscsi_cmd *cmd;
2471 	struct iscsi_conn *conn_p;
2472 
2473 	/*
2474 	 * Only send a Asynchronous Message on connections whos network
2475 	 * interface is still functional.
2476 	 */
2477 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2478 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2479 			iscsit_inc_conn_usage_count(conn_p);
2480 			break;
2481 		}
2482 	}
2483 
2484 	if (!conn_p)
2485 		return;
2486 
2487 	cmd = iscsit_allocate_cmd(conn_p, GFP_ATOMIC);
2488 	if (!cmd) {
2489 		iscsit_dec_conn_usage_count(conn_p);
2490 		return;
2491 	}
2492 
2493 	cmd->logout_cid = conn->cid;
2494 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2495 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2496 
2497 	spin_lock_bh(&conn_p->cmd_lock);
2498 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2499 	spin_unlock_bh(&conn_p->cmd_lock);
2500 
2501 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2502 	iscsit_dec_conn_usage_count(conn_p);
2503 }
2504 
2505 static int iscsit_send_conn_drop_async_message(
2506 	struct iscsi_cmd *cmd,
2507 	struct iscsi_conn *conn)
2508 {
2509 	struct iscsi_async *hdr;
2510 
2511 	cmd->tx_size = ISCSI_HDR_LEN;
2512 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2513 
2514 	hdr			= (struct iscsi_async *) cmd->pdu;
2515 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2516 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2517 	cmd->init_task_tag	= RESERVED_ITT;
2518 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2519 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2520 	cmd->stat_sn		= conn->stat_sn++;
2521 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2522 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2523 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2524 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2525 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2526 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2527 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2528 
2529 	if (conn->conn_ops->HeaderDigest) {
2530 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2531 
2532 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2533 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2534 
2535 		cmd->tx_size += ISCSI_CRC_LEN;
2536 		pr_debug("Attaching CRC32C HeaderDigest to"
2537 			" Async Message 0x%08x\n", *header_digest);
2538 	}
2539 
2540 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2541 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2542 	cmd->iov_misc_count		= 1;
2543 
2544 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2545 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2546 			cmd->logout_cid, conn->cid);
2547 	return 0;
2548 }
2549 
2550 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2551 {
2552 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2553 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2554 		wait_for_completion_interruptible_timeout(
2555 					&conn->tx_half_close_comp,
2556 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2557 	}
2558 }
2559 
2560 static void
2561 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2562 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2563 			bool set_statsn)
2564 {
2565 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2566 	hdr->flags		= datain->flags;
2567 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2568 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2569 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2570 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2571 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2572 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2573 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2574 		}
2575 	}
2576 	hton24(hdr->dlength, datain->length);
2577 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2578 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2579 				(struct scsi_lun *)&hdr->lun);
2580 	else
2581 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2582 
2583 	hdr->itt		= cmd->init_task_tag;
2584 
2585 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2586 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2587 	else
2588 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2589 	if (set_statsn)
2590 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2591 	else
2592 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2593 
2594 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2595 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2596 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2597 	hdr->offset		= cpu_to_be32(datain->offset);
2598 
2599 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2600 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2601 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2602 		ntohl(hdr->offset), datain->length, conn->cid);
2603 }
2604 
2605 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2606 {
2607 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2608 	struct iscsi_datain datain;
2609 	struct iscsi_datain_req *dr;
2610 	struct kvec *iov;
2611 	u32 iov_count = 0, tx_size = 0;
2612 	int eodr = 0, ret, iov_ret;
2613 	bool set_statsn = false;
2614 
2615 	memset(&datain, 0, sizeof(struct iscsi_datain));
2616 	dr = iscsit_get_datain_values(cmd, &datain);
2617 	if (!dr) {
2618 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2619 				cmd->init_task_tag);
2620 		return -1;
2621 	}
2622 	/*
2623 	 * Be paranoid and double check the logic for now.
2624 	 */
2625 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2626 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2627 			" datain.length: %u exceeds cmd->data_length: %u\n",
2628 			cmd->init_task_tag, datain.offset, datain.length,
2629 			cmd->se_cmd.data_length);
2630 		return -1;
2631 	}
2632 
2633 	spin_lock_bh(&conn->sess->session_stats_lock);
2634 	conn->sess->tx_data_octets += datain.length;
2635 	if (conn->sess->se_sess->se_node_acl) {
2636 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
2637 		conn->sess->se_sess->se_node_acl->read_bytes += datain.length;
2638 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
2639 	}
2640 	spin_unlock_bh(&conn->sess->session_stats_lock);
2641 	/*
2642 	 * Special case for successfully execution w/ both DATAIN
2643 	 * and Sense Data.
2644 	 */
2645 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2646 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2647 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2648 	else {
2649 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2650 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2651 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2652 			cmd->stat_sn = conn->stat_sn++;
2653 			set_statsn = true;
2654 		} else if (dr->dr_complete ==
2655 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2656 			set_statsn = true;
2657 	}
2658 
2659 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2660 
2661 	iov = &cmd->iov_data[0];
2662 	iov[iov_count].iov_base	= cmd->pdu;
2663 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2664 	tx_size += ISCSI_HDR_LEN;
2665 
2666 	if (conn->conn_ops->HeaderDigest) {
2667 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2668 
2669 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
2670 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2671 
2672 		iov[0].iov_len += ISCSI_CRC_LEN;
2673 		tx_size += ISCSI_CRC_LEN;
2674 
2675 		pr_debug("Attaching CRC32 HeaderDigest"
2676 			" for DataIN PDU 0x%08x\n", *header_digest);
2677 	}
2678 
2679 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
2680 				datain.offset, datain.length);
2681 	if (iov_ret < 0)
2682 		return -1;
2683 
2684 	iov_count += iov_ret;
2685 	tx_size += datain.length;
2686 
2687 	cmd->padding = ((-datain.length) & 3);
2688 	if (cmd->padding) {
2689 		iov[iov_count].iov_base		= cmd->pad_bytes;
2690 		iov[iov_count++].iov_len	= cmd->padding;
2691 		tx_size += cmd->padding;
2692 
2693 		pr_debug("Attaching %u padding bytes\n",
2694 				cmd->padding);
2695 	}
2696 	if (conn->conn_ops->DataDigest) {
2697 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2698 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2699 
2700 		iov[iov_count].iov_base	= &cmd->data_crc;
2701 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2702 		tx_size += ISCSI_CRC_LEN;
2703 
2704 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2705 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2706 	}
2707 
2708 	cmd->iov_data_count = iov_count;
2709 	cmd->tx_size = tx_size;
2710 
2711 	/* sendpage is preferred but can't insert markers */
2712 	if (!conn->conn_ops->IFMarker)
2713 		ret = iscsit_fe_sendpage_sg(cmd, conn);
2714 	else
2715 		ret = iscsit_send_tx_data(cmd, conn, 0);
2716 
2717 	iscsit_unmap_iovec(cmd);
2718 
2719 	if (ret < 0) {
2720 		iscsit_tx_thread_wait_for_tcp(conn);
2721 		return ret;
2722 	}
2723 
2724 	if (dr->dr_complete) {
2725 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2726 				2 : 1;
2727 		iscsit_free_datain_req(cmd, dr);
2728 	}
2729 
2730 	return eodr;
2731 }
2732 
2733 int
2734 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2735 			struct iscsi_logout_rsp *hdr)
2736 {
2737 	struct iscsi_conn *logout_conn = NULL;
2738 	struct iscsi_conn_recovery *cr = NULL;
2739 	struct iscsi_session *sess = conn->sess;
2740 	/*
2741 	 * The actual shutting down of Sessions and/or Connections
2742 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2743 	 * is done in scsi_logout_post_handler().
2744 	 */
2745 	switch (cmd->logout_reason) {
2746 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2747 		pr_debug("iSCSI session logout successful, setting"
2748 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2749 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2750 		break;
2751 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2752 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2753 			break;
2754 		/*
2755 		 * For CLOSECONNECTION logout requests carrying
2756 		 * a matching logout CID -> local CID, the reference
2757 		 * for the local CID will have been incremented in
2758 		 * iscsi_logout_closeconnection().
2759 		 *
2760 		 * For CLOSECONNECTION logout requests carrying
2761 		 * a different CID than the connection it arrived
2762 		 * on, the connection responding to cmd->logout_cid
2763 		 * is stopped in iscsit_logout_post_handler_diffcid().
2764 		 */
2765 
2766 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2767 			" successful.\n", cmd->logout_cid, conn->cid);
2768 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2769 		break;
2770 	case ISCSI_LOGOUT_REASON_RECOVERY:
2771 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2772 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2773 			break;
2774 		/*
2775 		 * If the connection is still active from our point of view
2776 		 * force connection recovery to occur.
2777 		 */
2778 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2779 				cmd->logout_cid);
2780 		if (logout_conn) {
2781 			iscsit_connection_reinstatement_rcfr(logout_conn);
2782 			iscsit_dec_conn_usage_count(logout_conn);
2783 		}
2784 
2785 		cr = iscsit_get_inactive_connection_recovery_entry(
2786 				conn->sess, cmd->logout_cid);
2787 		if (!cr) {
2788 			pr_err("Unable to locate CID: %hu for"
2789 			" REMOVECONNFORRECOVERY Logout Request.\n",
2790 				cmd->logout_cid);
2791 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2792 			break;
2793 		}
2794 
2795 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2796 
2797 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2798 			" for recovery for CID: %hu on CID: %hu successful.\n",
2799 				cmd->logout_cid, conn->cid);
2800 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2801 		break;
2802 	default:
2803 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2804 				cmd->logout_reason);
2805 		return -1;
2806 	}
2807 
2808 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2809 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2810 	hdr->response		= cmd->logout_response;
2811 	hdr->itt		= cmd->init_task_tag;
2812 	cmd->stat_sn		= conn->stat_sn++;
2813 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2814 
2815 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2816 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2817 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2818 
2819 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2820 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2821 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2822 		cmd->logout_cid, conn->cid);
2823 
2824 	return 0;
2825 }
2826 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2827 
2828 static int
2829 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2830 {
2831 	struct kvec *iov;
2832 	int niov = 0, tx_size, rc;
2833 
2834 	rc = iscsit_build_logout_rsp(cmd, conn,
2835 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2836 	if (rc < 0)
2837 		return rc;
2838 
2839 	tx_size = ISCSI_HDR_LEN;
2840 	iov = &cmd->iov_misc[0];
2841 	iov[niov].iov_base	= cmd->pdu;
2842 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2843 
2844 	if (conn->conn_ops->HeaderDigest) {
2845 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2846 
2847 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, &cmd->pdu[0],
2848 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2849 
2850 		iov[0].iov_len += ISCSI_CRC_LEN;
2851 		tx_size += ISCSI_CRC_LEN;
2852 		pr_debug("Attaching CRC32C HeaderDigest to"
2853 			" Logout Response 0x%08x\n", *header_digest);
2854 	}
2855 	cmd->iov_misc_count = niov;
2856 	cmd->tx_size = tx_size;
2857 
2858 	return 0;
2859 }
2860 
2861 void
2862 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2863 		       struct iscsi_nopin *hdr, bool nopout_response)
2864 {
2865 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2866 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2867         hton24(hdr->dlength, cmd->buf_ptr_size);
2868 	if (nopout_response)
2869 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2870 	hdr->itt		= cmd->init_task_tag;
2871 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2872 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2873 				  conn->stat_sn;
2874 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2875 
2876 	if (nopout_response)
2877 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2878 
2879 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2880 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2881 
2882 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2883 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2884 		"Solicitied" : "Unsolicitied", cmd->init_task_tag,
2885 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2886 }
2887 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2888 
2889 /*
2890  *	Unsolicited NOPIN, either requesting a response or not.
2891  */
2892 static int iscsit_send_unsolicited_nopin(
2893 	struct iscsi_cmd *cmd,
2894 	struct iscsi_conn *conn,
2895 	int want_response)
2896 {
2897 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2898 	int tx_size = ISCSI_HDR_LEN, ret;
2899 
2900 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
2901 
2902 	if (conn->conn_ops->HeaderDigest) {
2903 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2904 
2905 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2906 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2907 
2908 		tx_size += ISCSI_CRC_LEN;
2909 		pr_debug("Attaching CRC32C HeaderDigest to"
2910 			" NopIN 0x%08x\n", *header_digest);
2911 	}
2912 
2913 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2914 	cmd->iov_misc[0].iov_len	= tx_size;
2915 	cmd->iov_misc_count	= 1;
2916 	cmd->tx_size		= tx_size;
2917 
2918 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2919 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2920 
2921 	ret = iscsit_send_tx_data(cmd, conn, 1);
2922 	if (ret < 0) {
2923 		iscsit_tx_thread_wait_for_tcp(conn);
2924 		return ret;
2925 	}
2926 
2927 	spin_lock_bh(&cmd->istate_lock);
2928 	cmd->i_state = want_response ?
2929 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2930 	spin_unlock_bh(&cmd->istate_lock);
2931 
2932 	return 0;
2933 }
2934 
2935 static int
2936 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2937 {
2938 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2939 	struct kvec *iov;
2940 	u32 padding = 0;
2941 	int niov = 0, tx_size;
2942 
2943 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
2944 
2945 	tx_size = ISCSI_HDR_LEN;
2946 	iov = &cmd->iov_misc[0];
2947 	iov[niov].iov_base	= cmd->pdu;
2948 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2949 
2950 	if (conn->conn_ops->HeaderDigest) {
2951 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2952 
2953 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2954 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2955 
2956 		iov[0].iov_len += ISCSI_CRC_LEN;
2957 		tx_size += ISCSI_CRC_LEN;
2958 		pr_debug("Attaching CRC32C HeaderDigest"
2959 			" to NopIn 0x%08x\n", *header_digest);
2960 	}
2961 
2962 	/*
2963 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2964 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2965 	 */
2966 	if (cmd->buf_ptr_size) {
2967 		iov[niov].iov_base	= cmd->buf_ptr;
2968 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2969 		tx_size += cmd->buf_ptr_size;
2970 
2971 		pr_debug("Echoing back %u bytes of ping"
2972 			" data.\n", cmd->buf_ptr_size);
2973 
2974 		padding = ((-cmd->buf_ptr_size) & 3);
2975 		if (padding != 0) {
2976 			iov[niov].iov_base = &cmd->pad_bytes;
2977 			iov[niov++].iov_len = padding;
2978 			tx_size += padding;
2979 			pr_debug("Attaching %u additional"
2980 				" padding bytes.\n", padding);
2981 		}
2982 		if (conn->conn_ops->DataDigest) {
2983 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2984 				cmd->buf_ptr, cmd->buf_ptr_size,
2985 				padding, (u8 *)&cmd->pad_bytes,
2986 				(u8 *)&cmd->data_crc);
2987 
2988 			iov[niov].iov_base = &cmd->data_crc;
2989 			iov[niov++].iov_len = ISCSI_CRC_LEN;
2990 			tx_size += ISCSI_CRC_LEN;
2991 			pr_debug("Attached DataDigest for %u"
2992 				" bytes of ping data, CRC 0x%08x\n",
2993 				cmd->buf_ptr_size, cmd->data_crc);
2994 		}
2995 	}
2996 
2997 	cmd->iov_misc_count = niov;
2998 	cmd->tx_size = tx_size;
2999 
3000 	return 0;
3001 }
3002 
3003 static int iscsit_send_r2t(
3004 	struct iscsi_cmd *cmd,
3005 	struct iscsi_conn *conn)
3006 {
3007 	int tx_size = 0;
3008 	struct iscsi_r2t *r2t;
3009 	struct iscsi_r2t_rsp *hdr;
3010 	int ret;
3011 
3012 	r2t = iscsit_get_r2t_from_list(cmd);
3013 	if (!r2t)
3014 		return -1;
3015 
3016 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3017 	memset(hdr, 0, ISCSI_HDR_LEN);
3018 	hdr->opcode		= ISCSI_OP_R2T;
3019 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3020 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3021 			(struct scsi_lun *)&hdr->lun);
3022 	hdr->itt		= cmd->init_task_tag;
3023 	spin_lock_bh(&conn->sess->ttt_lock);
3024 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
3025 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
3026 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
3027 	spin_unlock_bh(&conn->sess->ttt_lock);
3028 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3029 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3030 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3031 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3032 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3033 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3034 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3035 
3036 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3037 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3038 	tx_size += ISCSI_HDR_LEN;
3039 
3040 	if (conn->conn_ops->HeaderDigest) {
3041 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3042 
3043 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3044 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3045 
3046 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3047 		tx_size += ISCSI_CRC_LEN;
3048 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
3049 			" PDU 0x%08x\n", *header_digest);
3050 	}
3051 
3052 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3053 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3054 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3055 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3056 			r2t->offset, r2t->xfer_len, conn->cid);
3057 
3058 	cmd->iov_misc_count = 1;
3059 	cmd->tx_size = tx_size;
3060 
3061 	spin_lock_bh(&cmd->r2t_lock);
3062 	r2t->sent_r2t = 1;
3063 	spin_unlock_bh(&cmd->r2t_lock);
3064 
3065 	ret = iscsit_send_tx_data(cmd, conn, 1);
3066 	if (ret < 0) {
3067 		iscsit_tx_thread_wait_for_tcp(conn);
3068 		return ret;
3069 	}
3070 
3071 	spin_lock_bh(&cmd->dataout_timeout_lock);
3072 	iscsit_start_dataout_timer(cmd, conn);
3073 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3074 
3075 	return 0;
3076 }
3077 
3078 /*
3079  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3080  *		connection recovery.
3081  */
3082 int iscsit_build_r2ts_for_cmd(
3083 	struct iscsi_conn *conn,
3084 	struct iscsi_cmd *cmd,
3085 	bool recovery)
3086 {
3087 	int first_r2t = 1;
3088 	u32 offset = 0, xfer_len = 0;
3089 
3090 	spin_lock_bh(&cmd->r2t_lock);
3091 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3092 		spin_unlock_bh(&cmd->r2t_lock);
3093 		return 0;
3094 	}
3095 
3096 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3097 	    !recovery)
3098 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3099 
3100 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3101 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3102 			offset = cmd->r2t_offset;
3103 
3104 			if (first_r2t && recovery) {
3105 				int new_data_end = offset +
3106 					conn->sess->sess_ops->MaxBurstLength -
3107 					cmd->next_burst_len;
3108 
3109 				if (new_data_end > cmd->se_cmd.data_length)
3110 					xfer_len = cmd->se_cmd.data_length - offset;
3111 				else
3112 					xfer_len =
3113 						conn->sess->sess_ops->MaxBurstLength -
3114 						cmd->next_burst_len;
3115 			} else {
3116 				int new_data_end = offset +
3117 					conn->sess->sess_ops->MaxBurstLength;
3118 
3119 				if (new_data_end > cmd->se_cmd.data_length)
3120 					xfer_len = cmd->se_cmd.data_length - offset;
3121 				else
3122 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3123 			}
3124 			cmd->r2t_offset += xfer_len;
3125 
3126 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3127 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3128 		} else {
3129 			struct iscsi_seq *seq;
3130 
3131 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3132 			if (!seq) {
3133 				spin_unlock_bh(&cmd->r2t_lock);
3134 				return -1;
3135 			}
3136 
3137 			offset = seq->offset;
3138 			xfer_len = seq->xfer_len;
3139 
3140 			if (cmd->seq_send_order == cmd->seq_count)
3141 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3142 		}
3143 		cmd->outstanding_r2ts++;
3144 		first_r2t = 0;
3145 
3146 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3147 			spin_unlock_bh(&cmd->r2t_lock);
3148 			return -1;
3149 		}
3150 
3151 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3152 			break;
3153 	}
3154 	spin_unlock_bh(&cmd->r2t_lock);
3155 
3156 	return 0;
3157 }
3158 
3159 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3160 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3161 {
3162 	if (inc_stat_sn)
3163 		cmd->stat_sn = conn->stat_sn++;
3164 
3165 	spin_lock_bh(&conn->sess->session_stats_lock);
3166 	conn->sess->rsp_pdus++;
3167 	spin_unlock_bh(&conn->sess->session_stats_lock);
3168 
3169 	memset(hdr, 0, ISCSI_HDR_LEN);
3170 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3171 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3172 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3173 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3174 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3175 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3176 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3177 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3178 	}
3179 	hdr->response		= cmd->iscsi_response;
3180 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3181 	hdr->itt		= cmd->init_task_tag;
3182 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3183 
3184 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3185 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3186 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3187 
3188 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3189 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3190 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3191 		cmd->se_cmd.scsi_status, conn->cid);
3192 }
3193 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3194 
3195 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3196 {
3197 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3198 	struct kvec *iov;
3199 	u32 padding = 0, tx_size = 0;
3200 	int iov_count = 0;
3201 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3202 
3203 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3204 
3205 	iov = &cmd->iov_misc[0];
3206 	iov[iov_count].iov_base	= cmd->pdu;
3207 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3208 	tx_size += ISCSI_HDR_LEN;
3209 
3210 	/*
3211 	 * Attach SENSE DATA payload to iSCSI Response PDU
3212 	 */
3213 	if (cmd->se_cmd.sense_buffer &&
3214 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3215 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3216 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3217 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3218 
3219 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3220 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3221 		iov[iov_count].iov_base	= cmd->sense_buffer;
3222 		iov[iov_count++].iov_len =
3223 				(cmd->se_cmd.scsi_sense_length + padding);
3224 		tx_size += cmd->se_cmd.scsi_sense_length;
3225 
3226 		if (padding) {
3227 			memset(cmd->sense_buffer +
3228 				cmd->se_cmd.scsi_sense_length, 0, padding);
3229 			tx_size += padding;
3230 			pr_debug("Adding %u bytes of padding to"
3231 				" SENSE.\n", padding);
3232 		}
3233 
3234 		if (conn->conn_ops->DataDigest) {
3235 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3236 				cmd->sense_buffer,
3237 				(cmd->se_cmd.scsi_sense_length + padding),
3238 				0, NULL, (u8 *)&cmd->data_crc);
3239 
3240 			iov[iov_count].iov_base    = &cmd->data_crc;
3241 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3242 			tx_size += ISCSI_CRC_LEN;
3243 
3244 			pr_debug("Attaching CRC32 DataDigest for"
3245 				" SENSE, %u bytes CRC 0x%08x\n",
3246 				(cmd->se_cmd.scsi_sense_length + padding),
3247 				cmd->data_crc);
3248 		}
3249 
3250 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3251 				" Response PDU\n",
3252 				cmd->se_cmd.scsi_sense_length);
3253 	}
3254 
3255 	if (conn->conn_ops->HeaderDigest) {
3256 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3257 
3258 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
3259 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3260 
3261 		iov[0].iov_len += ISCSI_CRC_LEN;
3262 		tx_size += ISCSI_CRC_LEN;
3263 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3264 				" PDU 0x%08x\n", *header_digest);
3265 	}
3266 
3267 	cmd->iov_misc_count = iov_count;
3268 	cmd->tx_size = tx_size;
3269 
3270 	return 0;
3271 }
3272 
3273 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3274 {
3275 	switch (se_tmr->response) {
3276 	case TMR_FUNCTION_COMPLETE:
3277 		return ISCSI_TMF_RSP_COMPLETE;
3278 	case TMR_TASK_DOES_NOT_EXIST:
3279 		return ISCSI_TMF_RSP_NO_TASK;
3280 	case TMR_LUN_DOES_NOT_EXIST:
3281 		return ISCSI_TMF_RSP_NO_LUN;
3282 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3283 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3284 	case TMR_FUNCTION_REJECTED:
3285 	default:
3286 		return ISCSI_TMF_RSP_REJECTED;
3287 	}
3288 }
3289 
3290 void
3291 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3292 			  struct iscsi_tm_rsp *hdr)
3293 {
3294 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3295 
3296 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3297 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3298 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3299 	hdr->itt		= cmd->init_task_tag;
3300 	cmd->stat_sn		= conn->stat_sn++;
3301 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3302 
3303 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3304 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3305 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3306 
3307 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3308 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3309 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3310 }
3311 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3312 
3313 static int
3314 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3315 {
3316 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3317 	u32 tx_size = 0;
3318 
3319 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3320 
3321 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3322 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3323 	tx_size += ISCSI_HDR_LEN;
3324 
3325 	if (conn->conn_ops->HeaderDigest) {
3326 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3327 
3328 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3329 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3330 
3331 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3332 		tx_size += ISCSI_CRC_LEN;
3333 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3334 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3335 	}
3336 
3337 	cmd->iov_misc_count = 1;
3338 	cmd->tx_size = tx_size;
3339 
3340 	return 0;
3341 }
3342 
3343 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3344 {
3345 	bool ret = false;
3346 
3347 	if (np->np_sockaddr.ss_family == AF_INET6) {
3348 		const struct sockaddr_in6 sin6 = {
3349 			.sin6_addr = IN6ADDR_ANY_INIT };
3350 		struct sockaddr_in6 *sock_in6 =
3351 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3352 
3353 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3354 				sin6.sin6_addr.s6_addr, 16))
3355 			ret = true;
3356 	} else {
3357 		struct sockaddr_in * sock_in =
3358 			(struct sockaddr_in *)&np->np_sockaddr;
3359 
3360 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3361 			ret = true;
3362 	}
3363 
3364 	return ret;
3365 }
3366 
3367 #define SENDTARGETS_BUF_LIMIT 32768U
3368 
3369 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3370 {
3371 	char *payload = NULL;
3372 	struct iscsi_conn *conn = cmd->conn;
3373 	struct iscsi_portal_group *tpg;
3374 	struct iscsi_tiqn *tiqn;
3375 	struct iscsi_tpg_np *tpg_np;
3376 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3377 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3378 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3379 
3380 	buffer_len = max(conn->conn_ops->MaxRecvDataSegmentLength,
3381 			 SENDTARGETS_BUF_LIMIT);
3382 
3383 	payload = kzalloc(buffer_len, GFP_KERNEL);
3384 	if (!payload) {
3385 		pr_err("Unable to allocate memory for sendtargets"
3386 				" response.\n");
3387 		return -ENOMEM;
3388 	}
3389 	/*
3390 	 * Locate pointer to iqn./eui. string for IFC_SENDTARGETS_SINGLE
3391 	 * explicit case..
3392 	 */
3393 	if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) {
3394 		text_ptr = strchr(text_in, '=');
3395 		if (!text_ptr) {
3396 			pr_err("Unable to locate '=' string in text_in:"
3397 			       " %s\n", text_in);
3398 			kfree(payload);
3399 			return -EINVAL;
3400 		}
3401 		/*
3402 		 * Skip over '=' character..
3403 		 */
3404 		text_ptr += 1;
3405 	}
3406 
3407 	spin_lock(&tiqn_lock);
3408 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3409 		if ((cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) &&
3410 		     strcmp(tiqn->tiqn, text_ptr)) {
3411 			continue;
3412 		}
3413 
3414 		len = sprintf(buf, "TargetName=%s", tiqn->tiqn);
3415 		len += 1;
3416 
3417 		if ((len + payload_len) > buffer_len) {
3418 			end_of_buf = 1;
3419 			goto eob;
3420 		}
3421 		memcpy(payload + payload_len, buf, len);
3422 		payload_len += len;
3423 
3424 		spin_lock(&tiqn->tiqn_tpg_lock);
3425 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3426 
3427 			spin_lock(&tpg->tpg_state_lock);
3428 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3429 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3430 				spin_unlock(&tpg->tpg_state_lock);
3431 				continue;
3432 			}
3433 			spin_unlock(&tpg->tpg_state_lock);
3434 
3435 			spin_lock(&tpg->tpg_np_lock);
3436 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3437 						tpg_np_list) {
3438 				struct iscsi_np *np = tpg_np->tpg_np;
3439 				bool inaddr_any = iscsit_check_inaddr_any(np);
3440 
3441 				len = sprintf(buf, "TargetAddress="
3442 					"%s:%hu,%hu",
3443 					(inaddr_any == false) ?
3444 						np->np_ip : conn->local_ip,
3445 					(inaddr_any == false) ?
3446 						np->np_port : conn->local_port,
3447 					tpg->tpgt);
3448 				len += 1;
3449 
3450 				if ((len + payload_len) > buffer_len) {
3451 					spin_unlock(&tpg->tpg_np_lock);
3452 					spin_unlock(&tiqn->tiqn_tpg_lock);
3453 					end_of_buf = 1;
3454 					goto eob;
3455 				}
3456 				memcpy(payload + payload_len, buf, len);
3457 				payload_len += len;
3458 			}
3459 			spin_unlock(&tpg->tpg_np_lock);
3460 		}
3461 		spin_unlock(&tiqn->tiqn_tpg_lock);
3462 eob:
3463 		if (end_of_buf)
3464 			break;
3465 
3466 		if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE)
3467 			break;
3468 	}
3469 	spin_unlock(&tiqn_lock);
3470 
3471 	cmd->buf_ptr = payload;
3472 
3473 	return payload_len;
3474 }
3475 
3476 int
3477 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3478 		      struct iscsi_text_rsp *hdr)
3479 {
3480 	int text_length, padding;
3481 
3482 	text_length = iscsit_build_sendtargets_response(cmd);
3483 	if (text_length < 0)
3484 		return text_length;
3485 
3486 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3487 	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3488 	padding = ((-text_length) & 3);
3489 	hton24(hdr->dlength, text_length);
3490 	hdr->itt = cmd->init_task_tag;
3491 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3492 	cmd->stat_sn = conn->stat_sn++;
3493 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3494 
3495 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3496 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3497 	hdr->max_cmdsn = cpu_to_be32(conn->sess->max_cmd_sn);
3498 
3499 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3500 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3501 		text_length, conn->cid);
3502 
3503 	return text_length + padding;
3504 }
3505 EXPORT_SYMBOL(iscsit_build_text_rsp);
3506 
3507 /*
3508  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3509  *	MaxRecvDataSegmentLength.
3510  */
3511 static int iscsit_send_text_rsp(
3512 	struct iscsi_cmd *cmd,
3513 	struct iscsi_conn *conn)
3514 {
3515 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3516 	struct kvec *iov;
3517 	u32 tx_size = 0;
3518 	int text_length, iov_count = 0, rc;
3519 
3520 	rc = iscsit_build_text_rsp(cmd, conn, hdr);
3521 	if (rc < 0)
3522 		return rc;
3523 
3524 	text_length = rc;
3525 	iov = &cmd->iov_misc[0];
3526 	iov[iov_count].iov_base = cmd->pdu;
3527 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3528 	iov[iov_count].iov_base	= cmd->buf_ptr;
3529 	iov[iov_count++].iov_len = text_length;
3530 
3531 	tx_size += (ISCSI_HDR_LEN + text_length);
3532 
3533 	if (conn->conn_ops->HeaderDigest) {
3534 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3535 
3536 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3537 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3538 
3539 		iov[0].iov_len += ISCSI_CRC_LEN;
3540 		tx_size += ISCSI_CRC_LEN;
3541 		pr_debug("Attaching CRC32 HeaderDigest for"
3542 			" Text Response PDU 0x%08x\n", *header_digest);
3543 	}
3544 
3545 	if (conn->conn_ops->DataDigest) {
3546 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3547 				cmd->buf_ptr, text_length,
3548 				0, NULL, (u8 *)&cmd->data_crc);
3549 
3550 		iov[iov_count].iov_base	= &cmd->data_crc;
3551 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3552 		tx_size	+= ISCSI_CRC_LEN;
3553 
3554 		pr_debug("Attaching DataDigest for %u bytes of text"
3555 			" data, CRC 0x%08x\n", text_length,
3556 			cmd->data_crc);
3557 	}
3558 
3559 	cmd->iov_misc_count = iov_count;
3560 	cmd->tx_size = tx_size;
3561 
3562 	return 0;
3563 }
3564 
3565 void
3566 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3567 		    struct iscsi_reject *hdr)
3568 {
3569 	hdr->opcode		= ISCSI_OP_REJECT;
3570 	hdr->reason		= cmd->reject_reason;
3571 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3572 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3573 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3574 	cmd->stat_sn		= conn->stat_sn++;
3575 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3576 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3577 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3578 
3579 }
3580 EXPORT_SYMBOL(iscsit_build_reject);
3581 
3582 static int iscsit_send_reject(
3583 	struct iscsi_cmd *cmd,
3584 	struct iscsi_conn *conn)
3585 {
3586 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3587 	struct kvec *iov;
3588 	u32 iov_count = 0, tx_size;
3589 
3590 	iscsit_build_reject(cmd, conn, hdr);
3591 
3592 	iov = &cmd->iov_misc[0];
3593 	iov[iov_count].iov_base = cmd->pdu;
3594 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3595 	iov[iov_count].iov_base = cmd->buf_ptr;
3596 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3597 
3598 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3599 
3600 	if (conn->conn_ops->HeaderDigest) {
3601 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3602 
3603 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3604 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3605 
3606 		iov[0].iov_len += ISCSI_CRC_LEN;
3607 		tx_size += ISCSI_CRC_LEN;
3608 		pr_debug("Attaching CRC32 HeaderDigest for"
3609 			" REJECT PDU 0x%08x\n", *header_digest);
3610 	}
3611 
3612 	if (conn->conn_ops->DataDigest) {
3613 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->buf_ptr,
3614 				ISCSI_HDR_LEN, 0, NULL, (u8 *)&cmd->data_crc);
3615 
3616 		iov[iov_count].iov_base = &cmd->data_crc;
3617 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3618 		tx_size += ISCSI_CRC_LEN;
3619 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3620 				" PDU 0x%08x\n", cmd->data_crc);
3621 	}
3622 
3623 	cmd->iov_misc_count = iov_count;
3624 	cmd->tx_size = tx_size;
3625 
3626 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3627 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3628 
3629 	return 0;
3630 }
3631 
3632 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3633 {
3634 	struct iscsi_thread_set *ts = conn->thread_set;
3635 	int ord, cpu;
3636 	/*
3637 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3638 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3639 	 *
3640 	 * Here we use thread_id to determine which CPU that this
3641 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3642 	 * execute upon.
3643 	 */
3644 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3645 	for_each_online_cpu(cpu) {
3646 		if (ord-- == 0) {
3647 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3648 			return;
3649 		}
3650 	}
3651 	/*
3652 	 * This should never be reached..
3653 	 */
3654 	dump_stack();
3655 	cpumask_setall(conn->conn_cpumask);
3656 }
3657 
3658 static inline void iscsit_thread_check_cpumask(
3659 	struct iscsi_conn *conn,
3660 	struct task_struct *p,
3661 	int mode)
3662 {
3663 	char buf[128];
3664 	/*
3665 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3666 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3667 	 */
3668 	if (mode == 1) {
3669 		if (!conn->conn_tx_reset_cpumask)
3670 			return;
3671 		conn->conn_tx_reset_cpumask = 0;
3672 	} else {
3673 		if (!conn->conn_rx_reset_cpumask)
3674 			return;
3675 		conn->conn_rx_reset_cpumask = 0;
3676 	}
3677 	/*
3678 	 * Update the CPU mask for this single kthread so that
3679 	 * both TX and RX kthreads are scheduled to run on the
3680 	 * same CPU.
3681 	 */
3682 	memset(buf, 0, 128);
3683 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3684 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3685 }
3686 
3687 static int
3688 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3689 {
3690 	int ret;
3691 
3692 	switch (state) {
3693 	case ISTATE_SEND_R2T:
3694 		ret = iscsit_send_r2t(cmd, conn);
3695 		if (ret < 0)
3696 			goto err;
3697 		break;
3698 	case ISTATE_REMOVE:
3699 		spin_lock_bh(&conn->cmd_lock);
3700 		list_del(&cmd->i_conn_node);
3701 		spin_unlock_bh(&conn->cmd_lock);
3702 
3703 		iscsit_free_cmd(cmd, false);
3704 		break;
3705 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3706 		iscsit_mod_nopin_response_timer(conn);
3707 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3708 		if (ret < 0)
3709 			goto err;
3710 		break;
3711 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3712 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3713 		if (ret < 0)
3714 			goto err;
3715 		break;
3716 	default:
3717 		pr_err("Unknown Opcode: 0x%02x ITT:"
3718 		       " 0x%08x, i_state: %d on CID: %hu\n",
3719 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3720 		       conn->cid);
3721 		goto err;
3722 	}
3723 
3724 	return 0;
3725 
3726 err:
3727 	return -1;
3728 }
3729 
3730 static int
3731 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3732 {
3733 	struct iscsit_transport *t = conn->conn_transport;
3734 	struct iscsi_queue_req *qr;
3735 	struct iscsi_cmd *cmd;
3736 	u8 state;
3737 	int ret;
3738 
3739 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3740 		atomic_set(&conn->check_immediate_queue, 0);
3741 		cmd = qr->cmd;
3742 		state = qr->state;
3743 		kmem_cache_free(lio_qr_cache, qr);
3744 
3745 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3746 		if (ret < 0)
3747 			return ret;
3748 	}
3749 
3750 	return 0;
3751 }
3752 
3753 static int
3754 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3755 {
3756 	int ret;
3757 
3758 check_rsp_state:
3759 	switch (state) {
3760 	case ISTATE_SEND_DATAIN:
3761 		ret = iscsit_send_datain(cmd, conn);
3762 		if (ret < 0)
3763 			goto err;
3764 		else if (!ret)
3765 			/* more drs */
3766 			goto check_rsp_state;
3767 		else if (ret == 1) {
3768 			/* all done */
3769 			spin_lock_bh(&cmd->istate_lock);
3770 			cmd->i_state = ISTATE_SENT_STATUS;
3771 			spin_unlock_bh(&cmd->istate_lock);
3772 
3773 			if (atomic_read(&conn->check_immediate_queue))
3774 				return 1;
3775 
3776 			return 0;
3777 		} else if (ret == 2) {
3778 			/* Still must send status,
3779 			   SCF_TRANSPORT_TASK_SENSE was set */
3780 			spin_lock_bh(&cmd->istate_lock);
3781 			cmd->i_state = ISTATE_SEND_STATUS;
3782 			spin_unlock_bh(&cmd->istate_lock);
3783 			state = ISTATE_SEND_STATUS;
3784 			goto check_rsp_state;
3785 		}
3786 
3787 		break;
3788 	case ISTATE_SEND_STATUS:
3789 	case ISTATE_SEND_STATUS_RECOVERY:
3790 		ret = iscsit_send_response(cmd, conn);
3791 		break;
3792 	case ISTATE_SEND_LOGOUTRSP:
3793 		ret = iscsit_send_logout(cmd, conn);
3794 		break;
3795 	case ISTATE_SEND_ASYNCMSG:
3796 		ret = iscsit_send_conn_drop_async_message(
3797 			cmd, conn);
3798 		break;
3799 	case ISTATE_SEND_NOPIN:
3800 		ret = iscsit_send_nopin(cmd, conn);
3801 		break;
3802 	case ISTATE_SEND_REJECT:
3803 		ret = iscsit_send_reject(cmd, conn);
3804 		break;
3805 	case ISTATE_SEND_TASKMGTRSP:
3806 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3807 		if (ret != 0)
3808 			break;
3809 		ret = iscsit_tmr_post_handler(cmd, conn);
3810 		if (ret != 0)
3811 			iscsit_fall_back_to_erl0(conn->sess);
3812 		break;
3813 	case ISTATE_SEND_TEXTRSP:
3814 		ret = iscsit_send_text_rsp(cmd, conn);
3815 		break;
3816 	default:
3817 		pr_err("Unknown Opcode: 0x%02x ITT:"
3818 		       " 0x%08x, i_state: %d on CID: %hu\n",
3819 		       cmd->iscsi_opcode, cmd->init_task_tag,
3820 		       state, conn->cid);
3821 		goto err;
3822 	}
3823 	if (ret < 0)
3824 		goto err;
3825 
3826 	if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3827 		iscsit_tx_thread_wait_for_tcp(conn);
3828 		iscsit_unmap_iovec(cmd);
3829 		goto err;
3830 	}
3831 	iscsit_unmap_iovec(cmd);
3832 
3833 	switch (state) {
3834 	case ISTATE_SEND_LOGOUTRSP:
3835 		if (!iscsit_logout_post_handler(cmd, conn))
3836 			goto restart;
3837 		/* fall through */
3838 	case ISTATE_SEND_STATUS:
3839 	case ISTATE_SEND_ASYNCMSG:
3840 	case ISTATE_SEND_NOPIN:
3841 	case ISTATE_SEND_STATUS_RECOVERY:
3842 	case ISTATE_SEND_TEXTRSP:
3843 	case ISTATE_SEND_TASKMGTRSP:
3844 	case ISTATE_SEND_REJECT:
3845 		spin_lock_bh(&cmd->istate_lock);
3846 		cmd->i_state = ISTATE_SENT_STATUS;
3847 		spin_unlock_bh(&cmd->istate_lock);
3848 		break;
3849 	default:
3850 		pr_err("Unknown Opcode: 0x%02x ITT:"
3851 		       " 0x%08x, i_state: %d on CID: %hu\n",
3852 		       cmd->iscsi_opcode, cmd->init_task_tag,
3853 		       cmd->i_state, conn->cid);
3854 		goto err;
3855 	}
3856 
3857 	if (atomic_read(&conn->check_immediate_queue))
3858 		return 1;
3859 
3860 	return 0;
3861 
3862 err:
3863 	return -1;
3864 restart:
3865 	return -EAGAIN;
3866 }
3867 
3868 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3869 {
3870 	struct iscsit_transport *t = conn->conn_transport;
3871 	struct iscsi_queue_req *qr;
3872 	struct iscsi_cmd *cmd;
3873 	u8 state;
3874 	int ret;
3875 
3876 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3877 		cmd = qr->cmd;
3878 		state = qr->state;
3879 		kmem_cache_free(lio_qr_cache, qr);
3880 
3881 		ret = t->iscsit_response_queue(conn, cmd, state);
3882 		if (ret == 1 || ret < 0)
3883 			return ret;
3884 	}
3885 
3886 	return 0;
3887 }
3888 
3889 int iscsi_target_tx_thread(void *arg)
3890 {
3891 	int ret = 0;
3892 	struct iscsi_conn *conn;
3893 	struct iscsi_thread_set *ts = arg;
3894 	/*
3895 	 * Allow ourselves to be interrupted by SIGINT so that a
3896 	 * connection recovery / failure event can be triggered externally.
3897 	 */
3898 	allow_signal(SIGINT);
3899 
3900 restart:
3901 	conn = iscsi_tx_thread_pre_handler(ts);
3902 	if (!conn)
3903 		goto out;
3904 
3905 	ret = 0;
3906 
3907 	while (!kthread_should_stop()) {
3908 		/*
3909 		 * Ensure that both TX and RX per connection kthreads
3910 		 * are scheduled to run on the same CPU.
3911 		 */
3912 		iscsit_thread_check_cpumask(conn, current, 1);
3913 
3914 		wait_event_interruptible(conn->queues_wq,
3915 					 !iscsit_conn_all_queues_empty(conn) ||
3916 					 ts->status == ISCSI_THREAD_SET_RESET);
3917 
3918 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3919 		     signal_pending(current))
3920 			goto transport_err;
3921 
3922 get_immediate:
3923 		ret = iscsit_handle_immediate_queue(conn);
3924 		if (ret < 0)
3925 			goto transport_err;
3926 
3927 		ret = iscsit_handle_response_queue(conn);
3928 		if (ret == 1)
3929 			goto get_immediate;
3930 		else if (ret == -EAGAIN)
3931 			goto restart;
3932 		else if (ret < 0)
3933 			goto transport_err;
3934 	}
3935 
3936 transport_err:
3937 	iscsit_take_action_for_connection_exit(conn);
3938 	goto restart;
3939 out:
3940 	return 0;
3941 }
3942 
3943 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3944 {
3945 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3946 	struct iscsi_cmd *cmd;
3947 	int ret = 0;
3948 
3949 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3950 	case ISCSI_OP_SCSI_CMD:
3951 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3952 		if (!cmd)
3953 			goto reject;
3954 
3955 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3956 		break;
3957 	case ISCSI_OP_SCSI_DATA_OUT:
3958 		ret = iscsit_handle_data_out(conn, buf);
3959 		break;
3960 	case ISCSI_OP_NOOP_OUT:
3961 		cmd = NULL;
3962 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3963 			cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3964 			if (!cmd)
3965 				goto reject;
3966 		}
3967 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3968 		break;
3969 	case ISCSI_OP_SCSI_TMFUNC:
3970 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3971 		if (!cmd)
3972 			goto reject;
3973 
3974 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3975 		break;
3976 	case ISCSI_OP_TEXT:
3977 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3978 		if (!cmd)
3979 			goto reject;
3980 
3981 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3982 		break;
3983 	case ISCSI_OP_LOGOUT:
3984 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3985 		if (!cmd)
3986 			goto reject;
3987 
3988 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3989 		if (ret > 0)
3990 			wait_for_completion_timeout(&conn->conn_logout_comp,
3991 					SECONDS_FOR_LOGOUT_COMP * HZ);
3992 		break;
3993 	case ISCSI_OP_SNACK:
3994 		ret = iscsit_handle_snack(conn, buf);
3995 		break;
3996 	default:
3997 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3998 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3999 			pr_err("Cannot recover from unknown"
4000 			" opcode while ERL=0, closing iSCSI connection.\n");
4001 			return -1;
4002 		}
4003 		if (!conn->conn_ops->OFMarker) {
4004 			pr_err("Unable to recover from unknown"
4005 			" opcode while OFMarker=No, closing iSCSI"
4006 				" connection.\n");
4007 			return -1;
4008 		}
4009 		if (iscsit_recover_from_unknown_opcode(conn) < 0) {
4010 			pr_err("Unable to recover from unknown"
4011 				" opcode, closing iSCSI connection.\n");
4012 			return -1;
4013 		}
4014 		break;
4015 	}
4016 
4017 	return ret;
4018 reject:
4019 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4020 }
4021 
4022 int iscsi_target_rx_thread(void *arg)
4023 {
4024 	int ret;
4025 	u8 buffer[ISCSI_HDR_LEN], opcode;
4026 	u32 checksum = 0, digest = 0;
4027 	struct iscsi_conn *conn = NULL;
4028 	struct iscsi_thread_set *ts = arg;
4029 	struct kvec iov;
4030 	/*
4031 	 * Allow ourselves to be interrupted by SIGINT so that a
4032 	 * connection recovery / failure event can be triggered externally.
4033 	 */
4034 	allow_signal(SIGINT);
4035 
4036 restart:
4037 	conn = iscsi_rx_thread_pre_handler(ts);
4038 	if (!conn)
4039 		goto out;
4040 
4041 	if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
4042 		struct completion comp;
4043 		int rc;
4044 
4045 		init_completion(&comp);
4046 		rc = wait_for_completion_interruptible(&comp);
4047 		if (rc < 0)
4048 			goto transport_err;
4049 
4050 		goto out;
4051 	}
4052 
4053 	while (!kthread_should_stop()) {
4054 		/*
4055 		 * Ensure that both TX and RX per connection kthreads
4056 		 * are scheduled to run on the same CPU.
4057 		 */
4058 		iscsit_thread_check_cpumask(conn, current, 0);
4059 
4060 		memset(buffer, 0, ISCSI_HDR_LEN);
4061 		memset(&iov, 0, sizeof(struct kvec));
4062 
4063 		iov.iov_base	= buffer;
4064 		iov.iov_len	= ISCSI_HDR_LEN;
4065 
4066 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4067 		if (ret != ISCSI_HDR_LEN) {
4068 			iscsit_rx_thread_wait_for_tcp(conn);
4069 			goto transport_err;
4070 		}
4071 
4072 		if (conn->conn_ops->HeaderDigest) {
4073 			iov.iov_base	= &digest;
4074 			iov.iov_len	= ISCSI_CRC_LEN;
4075 
4076 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4077 			if (ret != ISCSI_CRC_LEN) {
4078 				iscsit_rx_thread_wait_for_tcp(conn);
4079 				goto transport_err;
4080 			}
4081 
4082 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
4083 					buffer, ISCSI_HDR_LEN,
4084 					0, NULL, (u8 *)&checksum);
4085 
4086 			if (digest != checksum) {
4087 				pr_err("HeaderDigest CRC32C failed,"
4088 					" received 0x%08x, computed 0x%08x\n",
4089 					digest, checksum);
4090 				/*
4091 				 * Set the PDU to 0xff so it will intentionally
4092 				 * hit default in the switch below.
4093 				 */
4094 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4095 				spin_lock_bh(&conn->sess->session_stats_lock);
4096 				conn->sess->conn_digest_errors++;
4097 				spin_unlock_bh(&conn->sess->session_stats_lock);
4098 			} else {
4099 				pr_debug("Got HeaderDigest CRC32C"
4100 						" 0x%08x\n", checksum);
4101 			}
4102 		}
4103 
4104 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4105 			goto transport_err;
4106 
4107 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4108 
4109 		if (conn->sess->sess_ops->SessionType &&
4110 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4111 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4112 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4113 			" while in Discovery Session, rejecting.\n", opcode);
4114 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4115 					  buffer);
4116 			goto transport_err;
4117 		}
4118 
4119 		ret = iscsi_target_rx_opcode(conn, buffer);
4120 		if (ret < 0)
4121 			goto transport_err;
4122 	}
4123 
4124 transport_err:
4125 	if (!signal_pending(current))
4126 		atomic_set(&conn->transport_failed, 1);
4127 	iscsit_take_action_for_connection_exit(conn);
4128 	goto restart;
4129 out:
4130 	return 0;
4131 }
4132 
4133 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4134 {
4135 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4136 	struct iscsi_session *sess = conn->sess;
4137 	/*
4138 	 * We expect this function to only ever be called from either RX or TX
4139 	 * thread context via iscsit_close_connection() once the other context
4140 	 * has been reset -> returned sleeping pre-handler state.
4141 	 */
4142 	spin_lock_bh(&conn->cmd_lock);
4143 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
4144 
4145 		list_del(&cmd->i_conn_node);
4146 		spin_unlock_bh(&conn->cmd_lock);
4147 
4148 		iscsit_increment_maxcmdsn(cmd, sess);
4149 
4150 		iscsit_free_cmd(cmd, true);
4151 
4152 		spin_lock_bh(&conn->cmd_lock);
4153 	}
4154 	spin_unlock_bh(&conn->cmd_lock);
4155 }
4156 
4157 static void iscsit_stop_timers_for_cmds(
4158 	struct iscsi_conn *conn)
4159 {
4160 	struct iscsi_cmd *cmd;
4161 
4162 	spin_lock_bh(&conn->cmd_lock);
4163 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4164 		if (cmd->data_direction == DMA_TO_DEVICE)
4165 			iscsit_stop_dataout_timer(cmd);
4166 	}
4167 	spin_unlock_bh(&conn->cmd_lock);
4168 }
4169 
4170 int iscsit_close_connection(
4171 	struct iscsi_conn *conn)
4172 {
4173 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4174 	struct iscsi_session	*sess = conn->sess;
4175 
4176 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4177 		" %u\n", conn->cid, sess->sid);
4178 	/*
4179 	 * Always up conn_logout_comp just in case the RX Thread is sleeping
4180 	 * and the logout response never got sent because the connection
4181 	 * failed.
4182 	 */
4183 	complete(&conn->conn_logout_comp);
4184 
4185 	iscsi_release_thread_set(conn);
4186 
4187 	iscsit_stop_timers_for_cmds(conn);
4188 	iscsit_stop_nopin_response_timer(conn);
4189 	iscsit_stop_nopin_timer(conn);
4190 	iscsit_free_queue_reqs_for_conn(conn);
4191 
4192 	/*
4193 	 * During Connection recovery drop unacknowledged out of order
4194 	 * commands for this connection, and prepare the other commands
4195 	 * for realligence.
4196 	 *
4197 	 * During normal operation clear the out of order commands (but
4198 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4199 	 * struct iscsi_cmds.
4200 	 */
4201 	if (atomic_read(&conn->connection_recovery)) {
4202 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4203 		iscsit_prepare_cmds_for_realligance(conn);
4204 	} else {
4205 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4206 		iscsit_release_commands_from_conn(conn);
4207 	}
4208 
4209 	/*
4210 	 * Handle decrementing session or connection usage count if
4211 	 * a logout response was not able to be sent because the
4212 	 * connection failed.  Fall back to Session Recovery here.
4213 	 */
4214 	if (atomic_read(&conn->conn_logout_remove)) {
4215 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4216 			iscsit_dec_conn_usage_count(conn);
4217 			iscsit_dec_session_usage_count(sess);
4218 		}
4219 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4220 			iscsit_dec_conn_usage_count(conn);
4221 
4222 		atomic_set(&conn->conn_logout_remove, 0);
4223 		atomic_set(&sess->session_reinstatement, 0);
4224 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4225 	}
4226 
4227 	spin_lock_bh(&sess->conn_lock);
4228 	list_del(&conn->conn_list);
4229 
4230 	/*
4231 	 * Attempt to let the Initiator know this connection failed by
4232 	 * sending an Connection Dropped Async Message on another
4233 	 * active connection.
4234 	 */
4235 	if (atomic_read(&conn->connection_recovery))
4236 		iscsit_build_conn_drop_async_message(conn);
4237 
4238 	spin_unlock_bh(&sess->conn_lock);
4239 
4240 	/*
4241 	 * If connection reinstatement is being performed on this connection,
4242 	 * up the connection reinstatement semaphore that is being blocked on
4243 	 * in iscsit_cause_connection_reinstatement().
4244 	 */
4245 	spin_lock_bh(&conn->state_lock);
4246 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4247 		spin_unlock_bh(&conn->state_lock);
4248 		complete(&conn->conn_wait_comp);
4249 		wait_for_completion(&conn->conn_post_wait_comp);
4250 		spin_lock_bh(&conn->state_lock);
4251 	}
4252 
4253 	/*
4254 	 * If connection reinstatement is being performed on this connection
4255 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4256 	 * connection wait rcfr semaphore that is being blocked on
4257 	 * an iscsit_connection_reinstatement_rcfr().
4258 	 */
4259 	if (atomic_read(&conn->connection_wait_rcfr)) {
4260 		spin_unlock_bh(&conn->state_lock);
4261 		complete(&conn->conn_wait_rcfr_comp);
4262 		wait_for_completion(&conn->conn_post_wait_comp);
4263 		spin_lock_bh(&conn->state_lock);
4264 	}
4265 	atomic_set(&conn->connection_reinstatement, 1);
4266 	spin_unlock_bh(&conn->state_lock);
4267 
4268 	/*
4269 	 * If any other processes are accessing this connection pointer we
4270 	 * must wait until they have completed.
4271 	 */
4272 	iscsit_check_conn_usage_count(conn);
4273 
4274 	if (conn->conn_rx_hash.tfm)
4275 		crypto_free_hash(conn->conn_rx_hash.tfm);
4276 	if (conn->conn_tx_hash.tfm)
4277 		crypto_free_hash(conn->conn_tx_hash.tfm);
4278 
4279 	if (conn->conn_cpumask)
4280 		free_cpumask_var(conn->conn_cpumask);
4281 
4282 	kfree(conn->conn_ops);
4283 	conn->conn_ops = NULL;
4284 
4285 	if (conn->sock)
4286 		sock_release(conn->sock);
4287 
4288 	if (conn->conn_transport->iscsit_free_conn)
4289 		conn->conn_transport->iscsit_free_conn(conn);
4290 
4291 	iscsit_put_transport(conn->conn_transport);
4292 
4293 	conn->thread_set = NULL;
4294 
4295 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4296 	conn->conn_state = TARG_CONN_STATE_FREE;
4297 	kfree(conn);
4298 
4299 	spin_lock_bh(&sess->conn_lock);
4300 	atomic_dec(&sess->nconn);
4301 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4302 		" %s\n", atomic_read(&sess->nconn),
4303 		sess->sess_ops->InitiatorName);
4304 	/*
4305 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4306 	 * Session that they all fail.
4307 	 */
4308 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4309 	     !atomic_read(&sess->session_logout))
4310 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4311 
4312 	/*
4313 	 * If this was not the last connection in the session, and we are
4314 	 * performing session reinstatement or falling back to ERL=0, call
4315 	 * iscsit_stop_session() without sleeping to shutdown the other
4316 	 * active connections.
4317 	 */
4318 	if (atomic_read(&sess->nconn)) {
4319 		if (!atomic_read(&sess->session_reinstatement) &&
4320 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4321 			spin_unlock_bh(&sess->conn_lock);
4322 			return 0;
4323 		}
4324 		if (!atomic_read(&sess->session_stop_active)) {
4325 			atomic_set(&sess->session_stop_active, 1);
4326 			spin_unlock_bh(&sess->conn_lock);
4327 			iscsit_stop_session(sess, 0, 0);
4328 			return 0;
4329 		}
4330 		spin_unlock_bh(&sess->conn_lock);
4331 		return 0;
4332 	}
4333 
4334 	/*
4335 	 * If this was the last connection in the session and one of the
4336 	 * following is occurring:
4337 	 *
4338 	 * Session Reinstatement is not being performed, and are falling back
4339 	 * to ERL=0 call iscsit_close_session().
4340 	 *
4341 	 * Session Logout was requested.  iscsit_close_session() will be called
4342 	 * elsewhere.
4343 	 *
4344 	 * Session Continuation is not being performed, start the Time2Retain
4345 	 * handler and check if sleep_on_sess_wait_sem is active.
4346 	 */
4347 	if (!atomic_read(&sess->session_reinstatement) &&
4348 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4349 		spin_unlock_bh(&sess->conn_lock);
4350 		target_put_session(sess->se_sess);
4351 
4352 		return 0;
4353 	} else if (atomic_read(&sess->session_logout)) {
4354 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4355 		sess->session_state = TARG_SESS_STATE_FREE;
4356 		spin_unlock_bh(&sess->conn_lock);
4357 
4358 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4359 			complete(&sess->session_wait_comp);
4360 
4361 		return 0;
4362 	} else {
4363 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4364 		sess->session_state = TARG_SESS_STATE_FAILED;
4365 
4366 		if (!atomic_read(&sess->session_continuation)) {
4367 			spin_unlock_bh(&sess->conn_lock);
4368 			iscsit_start_time2retain_handler(sess);
4369 		} else
4370 			spin_unlock_bh(&sess->conn_lock);
4371 
4372 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4373 			complete(&sess->session_wait_comp);
4374 
4375 		return 0;
4376 	}
4377 	spin_unlock_bh(&sess->conn_lock);
4378 
4379 	return 0;
4380 }
4381 
4382 int iscsit_close_session(struct iscsi_session *sess)
4383 {
4384 	struct iscsi_portal_group *tpg = ISCSI_TPG_S(sess);
4385 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4386 
4387 	if (atomic_read(&sess->nconn)) {
4388 		pr_err("%d connection(s) still exist for iSCSI session"
4389 			" to %s\n", atomic_read(&sess->nconn),
4390 			sess->sess_ops->InitiatorName);
4391 		BUG();
4392 	}
4393 
4394 	spin_lock_bh(&se_tpg->session_lock);
4395 	atomic_set(&sess->session_logout, 1);
4396 	atomic_set(&sess->session_reinstatement, 1);
4397 	iscsit_stop_time2retain_timer(sess);
4398 	spin_unlock_bh(&se_tpg->session_lock);
4399 
4400 	/*
4401 	 * transport_deregister_session_configfs() will clear the
4402 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4403 	 * can be setting it again with __transport_register_session() in
4404 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4405 	 * completes in iscsi_np context.
4406 	 */
4407 	transport_deregister_session_configfs(sess->se_sess);
4408 
4409 	/*
4410 	 * If any other processes are accessing this session pointer we must
4411 	 * wait until they have completed.  If we are in an interrupt (the
4412 	 * time2retain handler) and contain and active session usage count we
4413 	 * restart the timer and exit.
4414 	 */
4415 	if (!in_interrupt()) {
4416 		if (iscsit_check_session_usage_count(sess) == 1)
4417 			iscsit_stop_session(sess, 1, 1);
4418 	} else {
4419 		if (iscsit_check_session_usage_count(sess) == 2) {
4420 			atomic_set(&sess->session_logout, 0);
4421 			iscsit_start_time2retain_handler(sess);
4422 			return 0;
4423 		}
4424 	}
4425 
4426 	transport_deregister_session(sess->se_sess);
4427 
4428 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4429 		iscsit_free_connection_recovery_entires(sess);
4430 
4431 	iscsit_free_all_ooo_cmdsns(sess);
4432 
4433 	spin_lock_bh(&se_tpg->session_lock);
4434 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4435 	sess->session_state = TARG_SESS_STATE_FREE;
4436 	pr_debug("Released iSCSI session from node: %s\n",
4437 			sess->sess_ops->InitiatorName);
4438 	tpg->nsessions--;
4439 	if (tpg->tpg_tiqn)
4440 		tpg->tpg_tiqn->tiqn_nsessions--;
4441 
4442 	pr_debug("Decremented number of active iSCSI Sessions on"
4443 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4444 
4445 	spin_lock(&sess_idr_lock);
4446 	idr_remove(&sess_idr, sess->session_index);
4447 	spin_unlock(&sess_idr_lock);
4448 
4449 	kfree(sess->sess_ops);
4450 	sess->sess_ops = NULL;
4451 	spin_unlock_bh(&se_tpg->session_lock);
4452 
4453 	kfree(sess);
4454 	return 0;
4455 }
4456 
4457 static void iscsit_logout_post_handler_closesession(
4458 	struct iscsi_conn *conn)
4459 {
4460 	struct iscsi_session *sess = conn->sess;
4461 
4462 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4463 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4464 
4465 	atomic_set(&conn->conn_logout_remove, 0);
4466 	complete(&conn->conn_logout_comp);
4467 
4468 	iscsit_dec_conn_usage_count(conn);
4469 	iscsit_stop_session(sess, 1, 1);
4470 	iscsit_dec_session_usage_count(sess);
4471 	target_put_session(sess->se_sess);
4472 }
4473 
4474 static void iscsit_logout_post_handler_samecid(
4475 	struct iscsi_conn *conn)
4476 {
4477 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4478 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4479 
4480 	atomic_set(&conn->conn_logout_remove, 0);
4481 	complete(&conn->conn_logout_comp);
4482 
4483 	iscsit_cause_connection_reinstatement(conn, 1);
4484 	iscsit_dec_conn_usage_count(conn);
4485 }
4486 
4487 static void iscsit_logout_post_handler_diffcid(
4488 	struct iscsi_conn *conn,
4489 	u16 cid)
4490 {
4491 	struct iscsi_conn *l_conn;
4492 	struct iscsi_session *sess = conn->sess;
4493 
4494 	if (!sess)
4495 		return;
4496 
4497 	spin_lock_bh(&sess->conn_lock);
4498 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4499 		if (l_conn->cid == cid) {
4500 			iscsit_inc_conn_usage_count(l_conn);
4501 			break;
4502 		}
4503 	}
4504 	spin_unlock_bh(&sess->conn_lock);
4505 
4506 	if (!l_conn)
4507 		return;
4508 
4509 	if (l_conn->sock)
4510 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4511 
4512 	spin_lock_bh(&l_conn->state_lock);
4513 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4514 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4515 	spin_unlock_bh(&l_conn->state_lock);
4516 
4517 	iscsit_cause_connection_reinstatement(l_conn, 1);
4518 	iscsit_dec_conn_usage_count(l_conn);
4519 }
4520 
4521 /*
4522  *	Return of 0 causes the TX thread to restart.
4523  */
4524 int iscsit_logout_post_handler(
4525 	struct iscsi_cmd *cmd,
4526 	struct iscsi_conn *conn)
4527 {
4528 	int ret = 0;
4529 
4530 	switch (cmd->logout_reason) {
4531 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4532 		switch (cmd->logout_response) {
4533 		case ISCSI_LOGOUT_SUCCESS:
4534 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4535 		default:
4536 			iscsit_logout_post_handler_closesession(conn);
4537 			break;
4538 		}
4539 		ret = 0;
4540 		break;
4541 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4542 		if (conn->cid == cmd->logout_cid) {
4543 			switch (cmd->logout_response) {
4544 			case ISCSI_LOGOUT_SUCCESS:
4545 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4546 			default:
4547 				iscsit_logout_post_handler_samecid(conn);
4548 				break;
4549 			}
4550 			ret = 0;
4551 		} else {
4552 			switch (cmd->logout_response) {
4553 			case ISCSI_LOGOUT_SUCCESS:
4554 				iscsit_logout_post_handler_diffcid(conn,
4555 					cmd->logout_cid);
4556 				break;
4557 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4558 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4559 			default:
4560 				break;
4561 			}
4562 			ret = 1;
4563 		}
4564 		break;
4565 	case ISCSI_LOGOUT_REASON_RECOVERY:
4566 		switch (cmd->logout_response) {
4567 		case ISCSI_LOGOUT_SUCCESS:
4568 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4569 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4570 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4571 		default:
4572 			break;
4573 		}
4574 		ret = 1;
4575 		break;
4576 	default:
4577 		break;
4578 
4579 	}
4580 	return ret;
4581 }
4582 EXPORT_SYMBOL(iscsit_logout_post_handler);
4583 
4584 void iscsit_fail_session(struct iscsi_session *sess)
4585 {
4586 	struct iscsi_conn *conn;
4587 
4588 	spin_lock_bh(&sess->conn_lock);
4589 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4590 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4591 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4592 	}
4593 	spin_unlock_bh(&sess->conn_lock);
4594 
4595 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4596 	sess->session_state = TARG_SESS_STATE_FAILED;
4597 }
4598 
4599 int iscsit_free_session(struct iscsi_session *sess)
4600 {
4601 	u16 conn_count = atomic_read(&sess->nconn);
4602 	struct iscsi_conn *conn, *conn_tmp = NULL;
4603 	int is_last;
4604 
4605 	spin_lock_bh(&sess->conn_lock);
4606 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4607 
4608 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4609 			conn_list) {
4610 		if (conn_count == 0)
4611 			break;
4612 
4613 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4614 			is_last = 1;
4615 		} else {
4616 			iscsit_inc_conn_usage_count(conn_tmp);
4617 			is_last = 0;
4618 		}
4619 		iscsit_inc_conn_usage_count(conn);
4620 
4621 		spin_unlock_bh(&sess->conn_lock);
4622 		iscsit_cause_connection_reinstatement(conn, 1);
4623 		spin_lock_bh(&sess->conn_lock);
4624 
4625 		iscsit_dec_conn_usage_count(conn);
4626 		if (is_last == 0)
4627 			iscsit_dec_conn_usage_count(conn_tmp);
4628 
4629 		conn_count--;
4630 	}
4631 
4632 	if (atomic_read(&sess->nconn)) {
4633 		spin_unlock_bh(&sess->conn_lock);
4634 		wait_for_completion(&sess->session_wait_comp);
4635 	} else
4636 		spin_unlock_bh(&sess->conn_lock);
4637 
4638 	target_put_session(sess->se_sess);
4639 	return 0;
4640 }
4641 
4642 void iscsit_stop_session(
4643 	struct iscsi_session *sess,
4644 	int session_sleep,
4645 	int connection_sleep)
4646 {
4647 	u16 conn_count = atomic_read(&sess->nconn);
4648 	struct iscsi_conn *conn, *conn_tmp = NULL;
4649 	int is_last;
4650 
4651 	spin_lock_bh(&sess->conn_lock);
4652 	if (session_sleep)
4653 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4654 
4655 	if (connection_sleep) {
4656 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4657 				conn_list) {
4658 			if (conn_count == 0)
4659 				break;
4660 
4661 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4662 				is_last = 1;
4663 			} else {
4664 				iscsit_inc_conn_usage_count(conn_tmp);
4665 				is_last = 0;
4666 			}
4667 			iscsit_inc_conn_usage_count(conn);
4668 
4669 			spin_unlock_bh(&sess->conn_lock);
4670 			iscsit_cause_connection_reinstatement(conn, 1);
4671 			spin_lock_bh(&sess->conn_lock);
4672 
4673 			iscsit_dec_conn_usage_count(conn);
4674 			if (is_last == 0)
4675 				iscsit_dec_conn_usage_count(conn_tmp);
4676 			conn_count--;
4677 		}
4678 	} else {
4679 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4680 			iscsit_cause_connection_reinstatement(conn, 0);
4681 	}
4682 
4683 	if (session_sleep && atomic_read(&sess->nconn)) {
4684 		spin_unlock_bh(&sess->conn_lock);
4685 		wait_for_completion(&sess->session_wait_comp);
4686 	} else
4687 		spin_unlock_bh(&sess->conn_lock);
4688 }
4689 
4690 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4691 {
4692 	struct iscsi_session *sess;
4693 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4694 	struct se_session *se_sess, *se_sess_tmp;
4695 	int session_count = 0;
4696 
4697 	spin_lock_bh(&se_tpg->session_lock);
4698 	if (tpg->nsessions && !force) {
4699 		spin_unlock_bh(&se_tpg->session_lock);
4700 		return -1;
4701 	}
4702 
4703 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4704 			sess_list) {
4705 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4706 
4707 		spin_lock(&sess->conn_lock);
4708 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4709 		    atomic_read(&sess->session_logout) ||
4710 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4711 			spin_unlock(&sess->conn_lock);
4712 			continue;
4713 		}
4714 		atomic_set(&sess->session_reinstatement, 1);
4715 		spin_unlock(&sess->conn_lock);
4716 		spin_unlock_bh(&se_tpg->session_lock);
4717 
4718 		iscsit_free_session(sess);
4719 		spin_lock_bh(&se_tpg->session_lock);
4720 
4721 		session_count++;
4722 	}
4723 	spin_unlock_bh(&se_tpg->session_lock);
4724 
4725 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4726 			" Group: %hu\n", session_count, tpg->tpgt);
4727 	return 0;
4728 }
4729 
4730 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4731 MODULE_VERSION("4.1.x");
4732 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4733 MODULE_LICENSE("GPL");
4734 
4735 module_init(iscsi_target_init_module);
4736 module_exit(iscsi_target_cleanup_module);
4737