1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
3  *
4  * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
5  *
6  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
7  *
8  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  ******************************************************************************/
20 
21 #include <linux/string.h>
22 #include <linux/kthread.h>
23 #include <linux/crypto.h>
24 #include <linux/completion.h>
25 #include <linux/module.h>
26 #include <linux/idr.h>
27 #include <asm/unaligned.h>
28 #include <scsi/scsi_device.h>
29 #include <scsi/iscsi_proto.h>
30 #include <scsi/scsi_tcq.h>
31 #include <target/target_core_base.h>
32 #include <target/target_core_fabric.h>
33 #include <target/target_core_configfs.h>
34 
35 #include "iscsi_target_core.h"
36 #include "iscsi_target_parameters.h"
37 #include "iscsi_target_seq_pdu_list.h"
38 #include "iscsi_target_tq.h"
39 #include "iscsi_target_configfs.h"
40 #include "iscsi_target_datain_values.h"
41 #include "iscsi_target_erl0.h"
42 #include "iscsi_target_erl1.h"
43 #include "iscsi_target_erl2.h"
44 #include "iscsi_target_login.h"
45 #include "iscsi_target_tmr.h"
46 #include "iscsi_target_tpg.h"
47 #include "iscsi_target_util.h"
48 #include "iscsi_target.h"
49 #include "iscsi_target_device.h"
50 #include "iscsi_target_stat.h"
51 
52 #include <target/iscsi/iscsi_transport.h>
53 
54 static LIST_HEAD(g_tiqn_list);
55 static LIST_HEAD(g_np_list);
56 static DEFINE_SPINLOCK(tiqn_lock);
57 static DEFINE_SPINLOCK(np_lock);
58 
59 static struct idr tiqn_idr;
60 struct idr sess_idr;
61 struct mutex auth_id_lock;
62 spinlock_t sess_idr_lock;
63 
64 struct iscsit_global *iscsit_global;
65 
66 struct kmem_cache *lio_cmd_cache;
67 struct kmem_cache *lio_qr_cache;
68 struct kmem_cache *lio_dr_cache;
69 struct kmem_cache *lio_ooo_cache;
70 struct kmem_cache *lio_r2t_cache;
71 
72 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
73 			struct iscsi_scsi_req *, u32);
74 
75 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
76 {
77 	struct iscsi_tiqn *tiqn = NULL;
78 
79 	spin_lock(&tiqn_lock);
80 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
81 		if (!strcmp(tiqn->tiqn, buf)) {
82 
83 			spin_lock(&tiqn->tiqn_state_lock);
84 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
85 				tiqn->tiqn_access_count++;
86 				spin_unlock(&tiqn->tiqn_state_lock);
87 				spin_unlock(&tiqn_lock);
88 				return tiqn;
89 			}
90 			spin_unlock(&tiqn->tiqn_state_lock);
91 		}
92 	}
93 	spin_unlock(&tiqn_lock);
94 
95 	return NULL;
96 }
97 
98 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
99 {
100 	spin_lock(&tiqn->tiqn_state_lock);
101 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
102 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
103 		spin_unlock(&tiqn->tiqn_state_lock);
104 		return 0;
105 	}
106 	spin_unlock(&tiqn->tiqn_state_lock);
107 
108 	return -1;
109 }
110 
111 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
112 {
113 	spin_lock(&tiqn->tiqn_state_lock);
114 	tiqn->tiqn_access_count--;
115 	spin_unlock(&tiqn->tiqn_state_lock);
116 }
117 
118 /*
119  * Note that IQN formatting is expected to be done in userspace, and
120  * no explict IQN format checks are done here.
121  */
122 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
123 {
124 	struct iscsi_tiqn *tiqn = NULL;
125 	int ret;
126 
127 	if (strlen(buf) >= ISCSI_IQN_LEN) {
128 		pr_err("Target IQN exceeds %d bytes\n",
129 				ISCSI_IQN_LEN);
130 		return ERR_PTR(-EINVAL);
131 	}
132 
133 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
134 	if (!tiqn) {
135 		pr_err("Unable to allocate struct iscsi_tiqn\n");
136 		return ERR_PTR(-ENOMEM);
137 	}
138 
139 	sprintf(tiqn->tiqn, "%s", buf);
140 	INIT_LIST_HEAD(&tiqn->tiqn_list);
141 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
142 	spin_lock_init(&tiqn->tiqn_state_lock);
143 	spin_lock_init(&tiqn->tiqn_tpg_lock);
144 	spin_lock_init(&tiqn->sess_err_stats.lock);
145 	spin_lock_init(&tiqn->login_stats.lock);
146 	spin_lock_init(&tiqn->logout_stats.lock);
147 
148 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
149 
150 	idr_preload(GFP_KERNEL);
151 	spin_lock(&tiqn_lock);
152 
153 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
154 	if (ret < 0) {
155 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
156 		spin_unlock(&tiqn_lock);
157 		idr_preload_end();
158 		kfree(tiqn);
159 		return ERR_PTR(ret);
160 	}
161 	tiqn->tiqn_index = ret;
162 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
163 
164 	spin_unlock(&tiqn_lock);
165 	idr_preload_end();
166 
167 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
168 
169 	return tiqn;
170 
171 }
172 
173 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
174 {
175 	/*
176 	 * Wait for accesses to said struct iscsi_tiqn to end.
177 	 */
178 	spin_lock(&tiqn->tiqn_state_lock);
179 	while (tiqn->tiqn_access_count != 0) {
180 		spin_unlock(&tiqn->tiqn_state_lock);
181 		msleep(10);
182 		spin_lock(&tiqn->tiqn_state_lock);
183 	}
184 	spin_unlock(&tiqn->tiqn_state_lock);
185 }
186 
187 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
188 {
189 	/*
190 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
191 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
192 	 * attempts to access this struct iscsi_tiqn will fail from both transport
193 	 * fabric and control code paths.
194 	 */
195 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
196 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
197 		return;
198 	}
199 
200 	iscsit_wait_for_tiqn(tiqn);
201 
202 	spin_lock(&tiqn_lock);
203 	list_del(&tiqn->tiqn_list);
204 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
205 	spin_unlock(&tiqn_lock);
206 
207 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
208 			tiqn->tiqn);
209 	kfree(tiqn);
210 }
211 
212 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
213 {
214 	int ret;
215 	/*
216 	 * Determine if the network portal is accepting storage traffic.
217 	 */
218 	spin_lock_bh(&np->np_thread_lock);
219 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
220 		spin_unlock_bh(&np->np_thread_lock);
221 		return -1;
222 	}
223 	if (np->np_login_tpg) {
224 		pr_err("np->np_login_tpg() is not NULL!\n");
225 		spin_unlock_bh(&np->np_thread_lock);
226 		return -1;
227 	}
228 	spin_unlock_bh(&np->np_thread_lock);
229 	/*
230 	 * Determine if the portal group is accepting storage traffic.
231 	 */
232 	spin_lock_bh(&tpg->tpg_state_lock);
233 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
234 		spin_unlock_bh(&tpg->tpg_state_lock);
235 		return -1;
236 	}
237 	spin_unlock_bh(&tpg->tpg_state_lock);
238 
239 	/*
240 	 * Here we serialize access across the TIQN+TPG Tuple.
241 	 */
242 	ret = mutex_lock_interruptible(&tpg->np_login_lock);
243 	if ((ret != 0) || signal_pending(current))
244 		return -1;
245 
246 	spin_lock_bh(&np->np_thread_lock);
247 	np->np_login_tpg = tpg;
248 	spin_unlock_bh(&np->np_thread_lock);
249 
250 	return 0;
251 }
252 
253 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
254 {
255 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
256 
257 	spin_lock_bh(&np->np_thread_lock);
258 	np->np_login_tpg = NULL;
259 	spin_unlock_bh(&np->np_thread_lock);
260 
261 	mutex_unlock(&tpg->np_login_lock);
262 
263 	if (tiqn)
264 		iscsit_put_tiqn_for_login(tiqn);
265 
266 	return 0;
267 }
268 
269 bool iscsit_check_np_match(
270 	struct __kernel_sockaddr_storage *sockaddr,
271 	struct iscsi_np *np,
272 	int network_transport)
273 {
274 	struct sockaddr_in *sock_in, *sock_in_e;
275 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
276 	bool ip_match = false;
277 	u16 port;
278 
279 	if (sockaddr->ss_family == AF_INET6) {
280 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
281 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
282 
283 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
284 			    &sock_in6_e->sin6_addr.in6_u,
285 			    sizeof(struct in6_addr)))
286 			ip_match = true;
287 
288 		port = ntohs(sock_in6->sin6_port);
289 	} else {
290 		sock_in = (struct sockaddr_in *)sockaddr;
291 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
292 
293 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
294 			ip_match = true;
295 
296 		port = ntohs(sock_in->sin_port);
297 	}
298 
299 	if ((ip_match == true) && (np->np_port == port) &&
300 	    (np->np_network_transport == network_transport))
301 		return true;
302 
303 	return false;
304 }
305 
306 static struct iscsi_np *iscsit_get_np(
307 	struct __kernel_sockaddr_storage *sockaddr,
308 	int network_transport)
309 {
310 	struct iscsi_np *np;
311 	bool match;
312 
313 	spin_lock_bh(&np_lock);
314 	list_for_each_entry(np, &g_np_list, np_list) {
315 		spin_lock(&np->np_thread_lock);
316 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
317 			spin_unlock(&np->np_thread_lock);
318 			continue;
319 		}
320 
321 		match = iscsit_check_np_match(sockaddr, np, network_transport);
322 		if (match == true) {
323 			/*
324 			 * Increment the np_exports reference count now to
325 			 * prevent iscsit_del_np() below from being called
326 			 * while iscsi_tpg_add_network_portal() is called.
327 			 */
328 			np->np_exports++;
329 			spin_unlock(&np->np_thread_lock);
330 			spin_unlock_bh(&np_lock);
331 			return np;
332 		}
333 		spin_unlock(&np->np_thread_lock);
334 	}
335 	spin_unlock_bh(&np_lock);
336 
337 	return NULL;
338 }
339 
340 struct iscsi_np *iscsit_add_np(
341 	struct __kernel_sockaddr_storage *sockaddr,
342 	char *ip_str,
343 	int network_transport)
344 {
345 	struct sockaddr_in *sock_in;
346 	struct sockaddr_in6 *sock_in6;
347 	struct iscsi_np *np;
348 	int ret;
349 	/*
350 	 * Locate the existing struct iscsi_np if already active..
351 	 */
352 	np = iscsit_get_np(sockaddr, network_transport);
353 	if (np)
354 		return np;
355 
356 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
357 	if (!np) {
358 		pr_err("Unable to allocate memory for struct iscsi_np\n");
359 		return ERR_PTR(-ENOMEM);
360 	}
361 
362 	np->np_flags |= NPF_IP_NETWORK;
363 	if (sockaddr->ss_family == AF_INET6) {
364 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
365 		snprintf(np->np_ip, IPV6_ADDRESS_SPACE, "%s", ip_str);
366 		np->np_port = ntohs(sock_in6->sin6_port);
367 	} else {
368 		sock_in = (struct sockaddr_in *)sockaddr;
369 		sprintf(np->np_ip, "%s", ip_str);
370 		np->np_port = ntohs(sock_in->sin_port);
371 	}
372 
373 	np->np_network_transport = network_transport;
374 	spin_lock_init(&np->np_thread_lock);
375 	init_completion(&np->np_restart_comp);
376 	INIT_LIST_HEAD(&np->np_list);
377 
378 	ret = iscsi_target_setup_login_socket(np, sockaddr);
379 	if (ret != 0) {
380 		kfree(np);
381 		return ERR_PTR(ret);
382 	}
383 
384 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
385 	if (IS_ERR(np->np_thread)) {
386 		pr_err("Unable to create kthread: iscsi_np\n");
387 		ret = PTR_ERR(np->np_thread);
388 		kfree(np);
389 		return ERR_PTR(ret);
390 	}
391 	/*
392 	 * Increment the np_exports reference count now to prevent
393 	 * iscsit_del_np() below from being run while a new call to
394 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
395 	 * active.  We don't need to hold np->np_thread_lock at this
396 	 * point because iscsi_np has not been added to g_np_list yet.
397 	 */
398 	np->np_exports = 1;
399 
400 	spin_lock_bh(&np_lock);
401 	list_add_tail(&np->np_list, &g_np_list);
402 	spin_unlock_bh(&np_lock);
403 
404 	pr_debug("CORE[0] - Added Network Portal: %s:%hu on %s\n",
405 		np->np_ip, np->np_port, np->np_transport->name);
406 
407 	return np;
408 }
409 
410 int iscsit_reset_np_thread(
411 	struct iscsi_np *np,
412 	struct iscsi_tpg_np *tpg_np,
413 	struct iscsi_portal_group *tpg)
414 {
415 	spin_lock_bh(&np->np_thread_lock);
416 	if (tpg && tpg_np) {
417 		/*
418 		 * The reset operation need only be performed when the
419 		 * passed struct iscsi_portal_group has a login in progress
420 		 * to one of the network portals.
421 		 */
422 		if (tpg_np->tpg_np->np_login_tpg != tpg) {
423 			spin_unlock_bh(&np->np_thread_lock);
424 			return 0;
425 		}
426 	}
427 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
428 		spin_unlock_bh(&np->np_thread_lock);
429 		return 0;
430 	}
431 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
432 
433 	if (np->np_thread) {
434 		spin_unlock_bh(&np->np_thread_lock);
435 		send_sig(SIGINT, np->np_thread, 1);
436 		wait_for_completion(&np->np_restart_comp);
437 		spin_lock_bh(&np->np_thread_lock);
438 	}
439 	spin_unlock_bh(&np->np_thread_lock);
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_alloc_cmd	= iscsit_alloc_cmd,
501 	.iscsit_get_login_rx	= iscsit_get_login_rx,
502 	.iscsit_put_login_tx	= iscsit_put_login_tx,
503 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
504 	.iscsit_immediate_queue	= iscsit_immediate_queue,
505 	.iscsit_response_queue	= iscsit_response_queue,
506 	.iscsit_queue_data_in	= iscsit_queue_rsp,
507 	.iscsit_queue_status	= iscsit_queue_rsp,
508 };
509 
510 static int __init iscsi_target_init_module(void)
511 {
512 	int ret = 0;
513 
514 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
515 
516 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
517 	if (!iscsit_global) {
518 		pr_err("Unable to allocate memory for iscsit_global\n");
519 		return -1;
520 	}
521 	mutex_init(&auth_id_lock);
522 	spin_lock_init(&sess_idr_lock);
523 	idr_init(&tiqn_idr);
524 	idr_init(&sess_idr);
525 
526 	ret = iscsi_target_register_configfs();
527 	if (ret < 0)
528 		goto out;
529 
530 	ret = iscsi_thread_set_init();
531 	if (ret < 0)
532 		goto configfs_out;
533 
534 	if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
535 			TARGET_THREAD_SET_COUNT) {
536 		pr_err("iscsi_allocate_thread_sets() returned"
537 			" unexpected value!\n");
538 		goto ts_out1;
539 	}
540 
541 	lio_cmd_cache = kmem_cache_create("lio_cmd_cache",
542 			sizeof(struct iscsi_cmd), __alignof__(struct iscsi_cmd),
543 			0, NULL);
544 	if (!lio_cmd_cache) {
545 		pr_err("Unable to kmem_cache_create() for"
546 				" lio_cmd_cache\n");
547 		goto ts_out2;
548 	}
549 
550 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
551 			sizeof(struct iscsi_queue_req),
552 			__alignof__(struct iscsi_queue_req), 0, NULL);
553 	if (!lio_qr_cache) {
554 		pr_err("nable to kmem_cache_create() for"
555 				" lio_qr_cache\n");
556 		goto cmd_out;
557 	}
558 
559 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
560 			sizeof(struct iscsi_datain_req),
561 			__alignof__(struct iscsi_datain_req), 0, NULL);
562 	if (!lio_dr_cache) {
563 		pr_err("Unable to kmem_cache_create() for"
564 				" lio_dr_cache\n");
565 		goto qr_out;
566 	}
567 
568 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
569 			sizeof(struct iscsi_ooo_cmdsn),
570 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
571 	if (!lio_ooo_cache) {
572 		pr_err("Unable to kmem_cache_create() for"
573 				" lio_ooo_cache\n");
574 		goto dr_out;
575 	}
576 
577 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
578 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
579 			0, NULL);
580 	if (!lio_r2t_cache) {
581 		pr_err("Unable to kmem_cache_create() for"
582 				" lio_r2t_cache\n");
583 		goto ooo_out;
584 	}
585 
586 	iscsit_register_transport(&iscsi_target_transport);
587 
588 	if (iscsit_load_discovery_tpg() < 0)
589 		goto r2t_out;
590 
591 	return ret;
592 r2t_out:
593 	kmem_cache_destroy(lio_r2t_cache);
594 ooo_out:
595 	kmem_cache_destroy(lio_ooo_cache);
596 dr_out:
597 	kmem_cache_destroy(lio_dr_cache);
598 qr_out:
599 	kmem_cache_destroy(lio_qr_cache);
600 cmd_out:
601 	kmem_cache_destroy(lio_cmd_cache);
602 ts_out2:
603 	iscsi_deallocate_thread_sets();
604 ts_out1:
605 	iscsi_thread_set_free();
606 configfs_out:
607 	iscsi_target_deregister_configfs();
608 out:
609 	kfree(iscsit_global);
610 	return -ENOMEM;
611 }
612 
613 static void __exit iscsi_target_cleanup_module(void)
614 {
615 	iscsi_deallocate_thread_sets();
616 	iscsi_thread_set_free();
617 	iscsit_release_discovery_tpg();
618 	iscsit_unregister_transport(&iscsi_target_transport);
619 	kmem_cache_destroy(lio_cmd_cache);
620 	kmem_cache_destroy(lio_qr_cache);
621 	kmem_cache_destroy(lio_dr_cache);
622 	kmem_cache_destroy(lio_ooo_cache);
623 	kmem_cache_destroy(lio_r2t_cache);
624 
625 	iscsi_target_deregister_configfs();
626 
627 	kfree(iscsit_global);
628 }
629 
630 static int iscsit_add_reject(
631 	struct iscsi_conn *conn,
632 	u8 reason,
633 	unsigned char *buf)
634 {
635 	struct iscsi_cmd *cmd;
636 
637 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
638 	if (!cmd)
639 		return -1;
640 
641 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
642 	cmd->reject_reason = reason;
643 
644 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
645 	if (!cmd->buf_ptr) {
646 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
647 		iscsit_free_cmd(cmd, false);
648 		return -1;
649 	}
650 
651 	spin_lock_bh(&conn->cmd_lock);
652 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
653 	spin_unlock_bh(&conn->cmd_lock);
654 
655 	cmd->i_state = ISTATE_SEND_REJECT;
656 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
657 
658 	return -1;
659 }
660 
661 static int iscsit_add_reject_from_cmd(
662 	struct iscsi_cmd *cmd,
663 	u8 reason,
664 	bool add_to_conn,
665 	unsigned char *buf)
666 {
667 	struct iscsi_conn *conn;
668 
669 	if (!cmd->conn) {
670 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
671 				cmd->init_task_tag);
672 		return -1;
673 	}
674 	conn = cmd->conn;
675 
676 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
677 	cmd->reject_reason = reason;
678 
679 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
680 	if (!cmd->buf_ptr) {
681 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
682 		iscsit_free_cmd(cmd, false);
683 		return -1;
684 	}
685 
686 	if (add_to_conn) {
687 		spin_lock_bh(&conn->cmd_lock);
688 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
689 		spin_unlock_bh(&conn->cmd_lock);
690 	}
691 
692 	cmd->i_state = ISTATE_SEND_REJECT;
693 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
694 	/*
695 	 * Perform the kref_put now if se_cmd has already been setup by
696 	 * scsit_setup_scsi_cmd()
697 	 */
698 	if (cmd->se_cmd.se_tfo != NULL) {
699 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
700 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
701 	}
702 	return -1;
703 }
704 
705 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
706 				 unsigned char *buf)
707 {
708 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
709 }
710 
711 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
712 {
713 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
714 }
715 
716 /*
717  * Map some portion of the allocated scatterlist to an iovec, suitable for
718  * kernel sockets to copy data in/out.
719  */
720 static int iscsit_map_iovec(
721 	struct iscsi_cmd *cmd,
722 	struct kvec *iov,
723 	u32 data_offset,
724 	u32 data_length)
725 {
726 	u32 i = 0;
727 	struct scatterlist *sg;
728 	unsigned int page_off;
729 
730 	/*
731 	 * We know each entry in t_data_sg contains a page.
732 	 */
733 	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
734 	page_off = (data_offset % PAGE_SIZE);
735 
736 	cmd->first_data_sg = sg;
737 	cmd->first_data_sg_off = page_off;
738 
739 	while (data_length) {
740 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
741 
742 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
743 		iov[i].iov_len = cur_len;
744 
745 		data_length -= cur_len;
746 		page_off = 0;
747 		sg = sg_next(sg);
748 		i++;
749 	}
750 
751 	cmd->kmapped_nents = i;
752 
753 	return i;
754 }
755 
756 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
757 {
758 	u32 i;
759 	struct scatterlist *sg;
760 
761 	sg = cmd->first_data_sg;
762 
763 	for (i = 0; i < cmd->kmapped_nents; i++)
764 		kunmap(sg_page(&sg[i]));
765 }
766 
767 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
768 {
769 	struct iscsi_cmd *cmd;
770 
771 	conn->exp_statsn = exp_statsn;
772 
773 	if (conn->sess->sess_ops->RDMAExtensions)
774 		return;
775 
776 	spin_lock_bh(&conn->cmd_lock);
777 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
778 		spin_lock(&cmd->istate_lock);
779 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
780 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
781 			cmd->i_state = ISTATE_REMOVE;
782 			spin_unlock(&cmd->istate_lock);
783 			iscsit_add_cmd_to_immediate_queue(cmd, conn,
784 						cmd->i_state);
785 			continue;
786 		}
787 		spin_unlock(&cmd->istate_lock);
788 	}
789 	spin_unlock_bh(&conn->cmd_lock);
790 }
791 
792 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
793 {
794 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
795 
796 	iov_count += ISCSI_IOV_DATA_BUFFER;
797 
798 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
799 	if (!cmd->iov_data) {
800 		pr_err("Unable to allocate cmd->iov_data\n");
801 		return -ENOMEM;
802 	}
803 
804 	cmd->orig_iov_data_count = iov_count;
805 	return 0;
806 }
807 
808 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
809 			  unsigned char *buf)
810 {
811 	int data_direction, payload_length;
812 	struct iscsi_scsi_req *hdr;
813 	int iscsi_task_attr;
814 	int sam_task_attr;
815 
816 	spin_lock_bh(&conn->sess->session_stats_lock);
817 	conn->sess->cmd_pdus++;
818 	if (conn->sess->se_sess->se_node_acl) {
819 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
820 		conn->sess->se_sess->se_node_acl->num_cmds++;
821 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
822 	}
823 	spin_unlock_bh(&conn->sess->session_stats_lock);
824 
825 	hdr			= (struct iscsi_scsi_req *) buf;
826 	payload_length		= ntoh24(hdr->dlength);
827 
828 	/* FIXME; Add checks for AdditionalHeaderSegment */
829 
830 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
831 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
832 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
833 				" not set. Bad iSCSI Initiator.\n");
834 		return iscsit_add_reject_cmd(cmd,
835 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
836 	}
837 
838 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
839 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
840 		/*
841 		 * Vmware ESX v3.0 uses a modified Cisco Initiator (v3.4.2)
842 		 * that adds support for RESERVE/RELEASE.  There is a bug
843 		 * add with this new functionality that sets R/W bits when
844 		 * neither CDB carries any READ or WRITE datapayloads.
845 		 */
846 		if ((hdr->cdb[0] == 0x16) || (hdr->cdb[0] == 0x17)) {
847 			hdr->flags &= ~ISCSI_FLAG_CMD_READ;
848 			hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
849 			goto done;
850 		}
851 
852 		pr_err("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
853 			" set when Expected Data Transfer Length is 0 for"
854 			" CDB: 0x%02x. Bad iSCSI Initiator.\n", hdr->cdb[0]);
855 		return iscsit_add_reject_cmd(cmd,
856 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
857 	}
858 done:
859 
860 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
861 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
862 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
863 			" MUST be set if Expected Data Transfer Length is not 0."
864 			" Bad iSCSI Initiator\n");
865 		return iscsit_add_reject_cmd(cmd,
866 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
867 	}
868 
869 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
870 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
871 		pr_err("Bidirectional operations not supported!\n");
872 		return iscsit_add_reject_cmd(cmd,
873 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
874 	}
875 
876 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
877 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
878 				" Scsi Command PDU.\n");
879 		return iscsit_add_reject_cmd(cmd,
880 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
881 	}
882 
883 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
884 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
885 			" protocol error.\n", payload_length);
886 		return iscsit_add_reject_cmd(cmd,
887 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
888 	}
889 
890 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
891 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
892 		pr_err("Expected Data Transfer Length and Length of"
893 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
894 			" bit is not set protocol error\n");
895 		return iscsit_add_reject_cmd(cmd,
896 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
897 	}
898 
899 	if (payload_length > be32_to_cpu(hdr->data_length)) {
900 		pr_err("DataSegmentLength: %u is greater than"
901 			" EDTL: %u, protocol error.\n", payload_length,
902 				hdr->data_length);
903 		return iscsit_add_reject_cmd(cmd,
904 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
905 	}
906 
907 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
908 		pr_err("DataSegmentLength: %u is greater than"
909 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
910 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
911 		return iscsit_add_reject_cmd(cmd,
912 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
913 	}
914 
915 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
916 		pr_err("DataSegmentLength: %u is greater than"
917 			" FirstBurstLength: %u, protocol error.\n",
918 			payload_length, conn->sess->sess_ops->FirstBurstLength);
919 		return iscsit_add_reject_cmd(cmd,
920 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
921 	}
922 
923 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
924 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
925 			  DMA_NONE;
926 
927 	cmd->data_direction = data_direction;
928 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
929 	/*
930 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
931 	 */
932 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
933 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
934 		sam_task_attr = MSG_SIMPLE_TAG;
935 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
936 		sam_task_attr = MSG_ORDERED_TAG;
937 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
938 		sam_task_attr = MSG_HEAD_TAG;
939 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
940 		sam_task_attr = MSG_ACA_TAG;
941 	else {
942 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
943 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
944 		sam_task_attr = MSG_SIMPLE_TAG;
945 	}
946 
947 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
948 	cmd->i_state		= ISTATE_NEW_CMD;
949 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
950 	cmd->immediate_data	= (payload_length) ? 1 : 0;
951 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
952 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
953 	if (cmd->unsolicited_data)
954 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
955 
956 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
957 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
958 		spin_lock_bh(&conn->sess->ttt_lock);
959 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
960 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
961 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
962 		spin_unlock_bh(&conn->sess->ttt_lock);
963 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
964 		cmd->targ_xfer_tag = 0xFFFFFFFF;
965 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
966 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
967 	cmd->first_burst_len	= payload_length;
968 
969 	if (!conn->sess->sess_ops->RDMAExtensions &&
970 	     cmd->data_direction == DMA_FROM_DEVICE) {
971 		struct iscsi_datain_req *dr;
972 
973 		dr = iscsit_allocate_datain_req();
974 		if (!dr)
975 			return iscsit_add_reject_cmd(cmd,
976 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
977 
978 		iscsit_attach_datain_req(cmd, dr);
979 	}
980 
981 	/*
982 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
983 	 */
984 	transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
985 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
986 			cmd->data_direction, sam_task_attr,
987 			cmd->sense_buffer + 2);
988 
989 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
990 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
991 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
992 		conn->cid);
993 
994 	target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
995 
996 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
997 						     scsilun_to_int(&hdr->lun));
998 	if (cmd->sense_reason)
999 		goto attach_cmd;
1000 
1001 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
1002 	if (cmd->sense_reason) {
1003 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1004 			return iscsit_add_reject_cmd(cmd,
1005 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1006 		}
1007 
1008 		goto attach_cmd;
1009 	}
1010 
1011 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1012 		return iscsit_add_reject_cmd(cmd,
1013 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1014 	}
1015 
1016 attach_cmd:
1017 	spin_lock_bh(&conn->cmd_lock);
1018 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1019 	spin_unlock_bh(&conn->cmd_lock);
1020 	/*
1021 	 * Check if we need to delay processing because of ALUA
1022 	 * Active/NonOptimized primary access state..
1023 	 */
1024 	core_alua_check_nonop_delay(&cmd->se_cmd);
1025 
1026 	return 0;
1027 }
1028 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1029 
1030 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1031 {
1032 	iscsit_set_dataout_sequence_values(cmd);
1033 
1034 	spin_lock_bh(&cmd->dataout_timeout_lock);
1035 	iscsit_start_dataout_timer(cmd, cmd->conn);
1036 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1037 }
1038 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1039 
1040 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1041 			    struct iscsi_scsi_req *hdr)
1042 {
1043 	int cmdsn_ret = 0;
1044 	/*
1045 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1046 	 * the Immediate Bit is not set, and no Immediate
1047 	 * Data is attached.
1048 	 *
1049 	 * A PDU/CmdSN carrying Immediate Data can only
1050 	 * be processed after the DataCRC has passed.
1051 	 * If the DataCRC fails, the CmdSN MUST NOT
1052 	 * be acknowledged. (See below)
1053 	 */
1054 	if (!cmd->immediate_data) {
1055 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1056 					(unsigned char *)hdr, hdr->cmdsn);
1057 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1058 			return -1;
1059 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1060 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1061 			return 0;
1062 		}
1063 	}
1064 
1065 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1066 
1067 	/*
1068 	 * If no Immediate Data is attached, it's OK to return now.
1069 	 */
1070 	if (!cmd->immediate_data) {
1071 		if (!cmd->sense_reason && cmd->unsolicited_data)
1072 			iscsit_set_unsoliticed_dataout(cmd);
1073 		if (!cmd->sense_reason)
1074 			return 0;
1075 
1076 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1077 		return 0;
1078 	}
1079 
1080 	/*
1081 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1082 	 * execution.  These exceptions are processed in CmdSN order using
1083 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1084 	 */
1085 	if (cmd->sense_reason) {
1086 		if (cmd->reject_reason)
1087 			return 0;
1088 
1089 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1090 		return 1;
1091 	}
1092 	/*
1093 	 * Call directly into transport_generic_new_cmd() to perform
1094 	 * the backend memory allocation.
1095 	 */
1096 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1097 	if (cmd->sense_reason)
1098 		return 1;
1099 
1100 	return 0;
1101 }
1102 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1103 
1104 static int
1105 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1106 			  bool dump_payload)
1107 {
1108 	struct iscsi_conn *conn = cmd->conn;
1109 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1110 	/*
1111 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1112 	 */
1113 	if (dump_payload == true)
1114 		goto after_immediate_data;
1115 
1116 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1117 					cmd->first_burst_len);
1118 after_immediate_data:
1119 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1120 		/*
1121 		 * A PDU/CmdSN carrying Immediate Data passed
1122 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1123 		 * Immediate Bit is not set.
1124 		 */
1125 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1126 					(unsigned char *)hdr, hdr->cmdsn);
1127 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
1128 			return -1;
1129 		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1130 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1131 			return 0;
1132 		}
1133 
1134 		if (cmd->sense_reason) {
1135 			int rc;
1136 
1137 			rc = iscsit_dump_data_payload(cmd->conn,
1138 						      cmd->first_burst_len, 1);
1139 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1140 			return rc;
1141 		} else if (cmd->unsolicited_data)
1142 			iscsit_set_unsoliticed_dataout(cmd);
1143 
1144 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1145 		/*
1146 		 * Immediate Data failed DataCRC and ERL>=1,
1147 		 * silently drop this PDU and let the initiator
1148 		 * plug the CmdSN gap.
1149 		 *
1150 		 * FIXME: Send Unsolicited NOPIN with reserved
1151 		 * TTT here to help the initiator figure out
1152 		 * the missing CmdSN, although they should be
1153 		 * intelligent enough to determine the missing
1154 		 * CmdSN and issue a retry to plug the sequence.
1155 		 */
1156 		cmd->i_state = ISTATE_REMOVE;
1157 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1158 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1159 		return -1;
1160 
1161 	return 0;
1162 }
1163 
1164 static int
1165 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1166 			   unsigned char *buf)
1167 {
1168 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1169 	int rc, immed_data;
1170 	bool dump_payload = false;
1171 
1172 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1173 	if (rc < 0)
1174 		return 0;
1175 	/*
1176 	 * Allocation iovecs needed for struct socket operations for
1177 	 * traditional iSCSI block I/O.
1178 	 */
1179 	if (iscsit_allocate_iovecs(cmd) < 0) {
1180 		return iscsit_add_reject_cmd(cmd,
1181 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1182 	}
1183 	immed_data = cmd->immediate_data;
1184 
1185 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1186 	if (rc < 0)
1187 		return rc;
1188 	else if (rc > 0)
1189 		dump_payload = true;
1190 
1191 	if (!immed_data)
1192 		return 0;
1193 
1194 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1195 }
1196 
1197 static u32 iscsit_do_crypto_hash_sg(
1198 	struct hash_desc *hash,
1199 	struct iscsi_cmd *cmd,
1200 	u32 data_offset,
1201 	u32 data_length,
1202 	u32 padding,
1203 	u8 *pad_bytes)
1204 {
1205 	u32 data_crc;
1206 	u32 i;
1207 	struct scatterlist *sg;
1208 	unsigned int page_off;
1209 
1210 	crypto_hash_init(hash);
1211 
1212 	sg = cmd->first_data_sg;
1213 	page_off = cmd->first_data_sg_off;
1214 
1215 	i = 0;
1216 	while (data_length) {
1217 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1218 
1219 		crypto_hash_update(hash, &sg[i], cur_len);
1220 
1221 		data_length -= cur_len;
1222 		page_off = 0;
1223 		i++;
1224 	}
1225 
1226 	if (padding) {
1227 		struct scatterlist pad_sg;
1228 
1229 		sg_init_one(&pad_sg, pad_bytes, padding);
1230 		crypto_hash_update(hash, &pad_sg, padding);
1231 	}
1232 	crypto_hash_final(hash, (u8 *) &data_crc);
1233 
1234 	return data_crc;
1235 }
1236 
1237 static void iscsit_do_crypto_hash_buf(
1238 	struct hash_desc *hash,
1239 	const void *buf,
1240 	u32 payload_length,
1241 	u32 padding,
1242 	u8 *pad_bytes,
1243 	u8 *data_crc)
1244 {
1245 	struct scatterlist sg;
1246 
1247 	crypto_hash_init(hash);
1248 
1249 	sg_init_one(&sg, buf, payload_length);
1250 	crypto_hash_update(hash, &sg, payload_length);
1251 
1252 	if (padding) {
1253 		sg_init_one(&sg, pad_bytes, padding);
1254 		crypto_hash_update(hash, &sg, padding);
1255 	}
1256 	crypto_hash_final(hash, data_crc);
1257 }
1258 
1259 int
1260 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1261 			  struct iscsi_cmd **out_cmd)
1262 {
1263 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1264 	struct iscsi_cmd *cmd = NULL;
1265 	struct se_cmd *se_cmd;
1266 	u32 payload_length = ntoh24(hdr->dlength);
1267 	int rc;
1268 
1269 	if (!payload_length) {
1270 		pr_err("DataOUT payload is ZERO, protocol error.\n");
1271 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1272 					 buf);
1273 	}
1274 
1275 	/* iSCSI write */
1276 	spin_lock_bh(&conn->sess->session_stats_lock);
1277 	conn->sess->rx_data_octets += payload_length;
1278 	if (conn->sess->se_sess->se_node_acl) {
1279 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
1280 		conn->sess->se_sess->se_node_acl->write_bytes += payload_length;
1281 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
1282 	}
1283 	spin_unlock_bh(&conn->sess->session_stats_lock);
1284 
1285 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1286 		pr_err("DataSegmentLength: %u is greater than"
1287 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1288 			conn->conn_ops->MaxXmitDataSegmentLength);
1289 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1290 					 buf);
1291 	}
1292 
1293 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1294 			payload_length);
1295 	if (!cmd)
1296 		return 0;
1297 
1298 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1299 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1300 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1301 		payload_length, conn->cid);
1302 
1303 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1304 		pr_err("Command ITT: 0x%08x received DataOUT after"
1305 			" last DataOUT received, dumping payload\n",
1306 			cmd->init_task_tag);
1307 		return iscsit_dump_data_payload(conn, payload_length, 1);
1308 	}
1309 
1310 	if (cmd->data_direction != DMA_TO_DEVICE) {
1311 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1312 			" NON-WRITE command.\n", cmd->init_task_tag);
1313 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
1314 	}
1315 	se_cmd = &cmd->se_cmd;
1316 	iscsit_mod_dataout_timer(cmd);
1317 
1318 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1319 		pr_err("DataOut Offset: %u, Length %u greater than"
1320 			" iSCSI Command EDTL %u, protocol error.\n",
1321 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1322 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1323 	}
1324 
1325 	if (cmd->unsolicited_data) {
1326 		int dump_unsolicited_data = 0;
1327 
1328 		if (conn->sess->sess_ops->InitialR2T) {
1329 			pr_err("Received unexpected unsolicited data"
1330 				" while InitialR2T=Yes, protocol error.\n");
1331 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1332 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1333 			return -1;
1334 		}
1335 		/*
1336 		 * Special case for dealing with Unsolicited DataOUT
1337 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1338 		 * failures;
1339 		 */
1340 
1341 		/* Something's amiss if we're not in WRITE_PENDING state... */
1342 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1343 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1344 			dump_unsolicited_data = 1;
1345 
1346 		if (dump_unsolicited_data) {
1347 			/*
1348 			 * Check if a delayed TASK_ABORTED status needs to
1349 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1350 			 * received with the unsolicitied data out.
1351 			 */
1352 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1353 				iscsit_stop_dataout_timer(cmd);
1354 
1355 			transport_check_aborted_status(se_cmd,
1356 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1357 			return iscsit_dump_data_payload(conn, payload_length, 1);
1358 		}
1359 	} else {
1360 		/*
1361 		 * For the normal solicited data path:
1362 		 *
1363 		 * Check for a delayed TASK_ABORTED status and dump any
1364 		 * incoming data out payload if one exists.  Also, when the
1365 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1366 		 * data out sequence, we decrement outstanding_r2ts.  Once
1367 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1368 		 * TASK_ABORTED status.
1369 		 */
1370 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1371 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1372 				if (--cmd->outstanding_r2ts < 1) {
1373 					iscsit_stop_dataout_timer(cmd);
1374 					transport_check_aborted_status(
1375 							se_cmd, 1);
1376 				}
1377 
1378 			return iscsit_dump_data_payload(conn, payload_length, 1);
1379 		}
1380 	}
1381 	/*
1382 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1383 	 * within-command recovery checks before receiving the payload.
1384 	 */
1385 	rc = iscsit_check_pre_dataout(cmd, buf);
1386 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1387 		return 0;
1388 	else if (rc == DATAOUT_CANNOT_RECOVER)
1389 		return -1;
1390 
1391 	*out_cmd = cmd;
1392 	return 0;
1393 }
1394 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1395 
1396 static int
1397 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1398 		   struct iscsi_data *hdr)
1399 {
1400 	struct kvec *iov;
1401 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1402 	u32 payload_length = ntoh24(hdr->dlength);
1403 	int iov_ret, data_crc_failed = 0;
1404 
1405 	rx_size += payload_length;
1406 	iov = &cmd->iov_data[0];
1407 
1408 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1409 				   payload_length);
1410 	if (iov_ret < 0)
1411 		return -1;
1412 
1413 	iov_count += iov_ret;
1414 
1415 	padding = ((-payload_length) & 3);
1416 	if (padding != 0) {
1417 		iov[iov_count].iov_base	= cmd->pad_bytes;
1418 		iov[iov_count++].iov_len = padding;
1419 		rx_size += padding;
1420 		pr_debug("Receiving %u padding bytes.\n", padding);
1421 	}
1422 
1423 	if (conn->conn_ops->DataDigest) {
1424 		iov[iov_count].iov_base = &checksum;
1425 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1426 		rx_size += ISCSI_CRC_LEN;
1427 	}
1428 
1429 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1430 
1431 	iscsit_unmap_iovec(cmd);
1432 
1433 	if (rx_got != rx_size)
1434 		return -1;
1435 
1436 	if (conn->conn_ops->DataDigest) {
1437 		u32 data_crc;
1438 
1439 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1440 						    be32_to_cpu(hdr->offset),
1441 						    payload_length, padding,
1442 						    cmd->pad_bytes);
1443 
1444 		if (checksum != data_crc) {
1445 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1446 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1447 				" does not match computed 0x%08x\n",
1448 				hdr->itt, hdr->offset, payload_length,
1449 				hdr->datasn, checksum, data_crc);
1450 			data_crc_failed = 1;
1451 		} else {
1452 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1453 				" %u bytes of Data Out\n", checksum,
1454 				payload_length);
1455 		}
1456 	}
1457 
1458 	return data_crc_failed;
1459 }
1460 
1461 int
1462 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1463 			     bool data_crc_failed)
1464 {
1465 	struct iscsi_conn *conn = cmd->conn;
1466 	int rc, ooo_cmdsn;
1467 	/*
1468 	 * Increment post receive data and CRC values or perform
1469 	 * within-command recovery.
1470 	 */
1471 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1472 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1473 		return 0;
1474 	else if (rc == DATAOUT_SEND_R2T) {
1475 		iscsit_set_dataout_sequence_values(cmd);
1476 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1477 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1478 		/*
1479 		 * Handle extra special case for out of order
1480 		 * Unsolicited Data Out.
1481 		 */
1482 		spin_lock_bh(&cmd->istate_lock);
1483 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1484 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1485 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1486 		spin_unlock_bh(&cmd->istate_lock);
1487 
1488 		iscsit_stop_dataout_timer(cmd);
1489 		if (ooo_cmdsn)
1490 			return 0;
1491 		target_execute_cmd(&cmd->se_cmd);
1492 		return 0;
1493 	} else /* DATAOUT_CANNOT_RECOVER */
1494 		return -1;
1495 
1496 	return 0;
1497 }
1498 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1499 
1500 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1501 {
1502 	struct iscsi_cmd *cmd;
1503 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1504 	int rc;
1505 	bool data_crc_failed = false;
1506 
1507 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1508 	if (rc < 0)
1509 		return 0;
1510 	else if (!cmd)
1511 		return 0;
1512 
1513 	rc = iscsit_get_dataout(conn, cmd, hdr);
1514 	if (rc < 0)
1515 		return rc;
1516 	else if (rc > 0)
1517 		data_crc_failed = true;
1518 
1519 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1520 }
1521 
1522 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1523 			 struct iscsi_nopout *hdr)
1524 {
1525 	u32 payload_length = ntoh24(hdr->dlength);
1526 
1527 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1528 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1529 			" not set, protocol error.\n");
1530 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1531 					 (unsigned char *)hdr);
1532 	}
1533 
1534 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1535 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1536 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1537 			" error.\n", payload_length,
1538 			conn->conn_ops->MaxXmitDataSegmentLength);
1539 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1540 					 (unsigned char *)hdr);
1541 	}
1542 
1543 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1544 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1545 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1546 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1547 		payload_length);
1548 	/*
1549 	 * This is not a response to a Unsolicited NopIN, which means
1550 	 * it can either be a NOPOUT ping request (with a valid ITT),
1551 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1552 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1553 	 * can contain ping data.
1554 	 */
1555 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1556 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1557 		cmd->i_state		= ISTATE_SEND_NOPIN;
1558 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1559 						1 : 0);
1560 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1561 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1562 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1563 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1564 		cmd->data_direction	= DMA_NONE;
1565 	}
1566 
1567 	return 0;
1568 }
1569 EXPORT_SYMBOL(iscsit_setup_nop_out);
1570 
1571 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1572 			   struct iscsi_nopout *hdr)
1573 {
1574 	struct iscsi_cmd *cmd_p = NULL;
1575 	int cmdsn_ret = 0;
1576 	/*
1577 	 * Initiator is expecting a NopIN ping reply..
1578 	 */
1579 	if (hdr->itt != RESERVED_ITT) {
1580 		BUG_ON(!cmd);
1581 
1582 		spin_lock_bh(&conn->cmd_lock);
1583 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1584 		spin_unlock_bh(&conn->cmd_lock);
1585 
1586 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1587 
1588 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1589 			iscsit_add_cmd_to_response_queue(cmd, conn,
1590 							 cmd->i_state);
1591 			return 0;
1592 		}
1593 
1594 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1595 				(unsigned char *)hdr, hdr->cmdsn);
1596                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1597 			return 0;
1598 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1599 			return -1;
1600 
1601 		return 0;
1602 	}
1603 	/*
1604 	 * This was a response to a unsolicited NOPIN ping.
1605 	 */
1606 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1607 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1608 		if (!cmd_p)
1609 			return -EINVAL;
1610 
1611 		iscsit_stop_nopin_response_timer(conn);
1612 
1613 		cmd_p->i_state = ISTATE_REMOVE;
1614 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1615 
1616 		iscsit_start_nopin_timer(conn);
1617 		return 0;
1618 	}
1619 	/*
1620 	 * Otherwise, initiator is not expecting a NOPIN is response.
1621 	 * Just ignore for now.
1622 	 */
1623         return 0;
1624 }
1625 EXPORT_SYMBOL(iscsit_process_nop_out);
1626 
1627 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1628 				 unsigned char *buf)
1629 {
1630 	unsigned char *ping_data = NULL;
1631 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1632 	struct kvec *iov = NULL;
1633 	u32 payload_length = ntoh24(hdr->dlength);
1634 	int ret;
1635 
1636 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1637 	if (ret < 0)
1638 		return 0;
1639 	/*
1640 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1641 	 */
1642 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1643 		u32 checksum, data_crc, padding = 0;
1644 		int niov = 0, rx_got, rx_size = payload_length;
1645 
1646 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1647 		if (!ping_data) {
1648 			pr_err("Unable to allocate memory for"
1649 				" NOPOUT ping data.\n");
1650 			ret = -1;
1651 			goto out;
1652 		}
1653 
1654 		iov = &cmd->iov_misc[0];
1655 		iov[niov].iov_base	= ping_data;
1656 		iov[niov++].iov_len	= payload_length;
1657 
1658 		padding = ((-payload_length) & 3);
1659 		if (padding != 0) {
1660 			pr_debug("Receiving %u additional bytes"
1661 				" for padding.\n", padding);
1662 			iov[niov].iov_base	= &cmd->pad_bytes;
1663 			iov[niov++].iov_len	= padding;
1664 			rx_size += padding;
1665 		}
1666 		if (conn->conn_ops->DataDigest) {
1667 			iov[niov].iov_base	= &checksum;
1668 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1669 			rx_size += ISCSI_CRC_LEN;
1670 		}
1671 
1672 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1673 		if (rx_got != rx_size) {
1674 			ret = -1;
1675 			goto out;
1676 		}
1677 
1678 		if (conn->conn_ops->DataDigest) {
1679 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1680 					ping_data, payload_length,
1681 					padding, cmd->pad_bytes,
1682 					(u8 *)&data_crc);
1683 
1684 			if (checksum != data_crc) {
1685 				pr_err("Ping data CRC32C DataDigest"
1686 				" 0x%08x does not match computed 0x%08x\n",
1687 					checksum, data_crc);
1688 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1689 					pr_err("Unable to recover from"
1690 					" NOPOUT Ping DataCRC failure while in"
1691 						" ERL=0.\n");
1692 					ret = -1;
1693 					goto out;
1694 				} else {
1695 					/*
1696 					 * Silently drop this PDU and let the
1697 					 * initiator plug the CmdSN gap.
1698 					 */
1699 					pr_debug("Dropping NOPOUT"
1700 					" Command CmdSN: 0x%08x due to"
1701 					" DataCRC error.\n", hdr->cmdsn);
1702 					ret = 0;
1703 					goto out;
1704 				}
1705 			} else {
1706 				pr_debug("Got CRC32C DataDigest"
1707 				" 0x%08x for %u bytes of ping data.\n",
1708 					checksum, payload_length);
1709 			}
1710 		}
1711 
1712 		ping_data[payload_length] = '\0';
1713 		/*
1714 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1715 		 */
1716 		cmd->buf_ptr = ping_data;
1717 		cmd->buf_ptr_size = payload_length;
1718 
1719 		pr_debug("Got %u bytes of NOPOUT ping"
1720 			" data.\n", payload_length);
1721 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1722 	}
1723 
1724 	return iscsit_process_nop_out(conn, cmd, hdr);
1725 out:
1726 	if (cmd)
1727 		iscsit_free_cmd(cmd, false);
1728 
1729 	kfree(ping_data);
1730 	return ret;
1731 }
1732 
1733 int
1734 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1735 			   unsigned char *buf)
1736 {
1737 	struct se_tmr_req *se_tmr;
1738 	struct iscsi_tmr_req *tmr_req;
1739 	struct iscsi_tm *hdr;
1740 	int out_of_order_cmdsn = 0, ret;
1741 	bool sess_ref = false;
1742 	u8 function;
1743 
1744 	hdr			= (struct iscsi_tm *) buf;
1745 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1746 	function = hdr->flags;
1747 
1748 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1749 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1750 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1751 		hdr->rtt, hdr->refcmdsn, conn->cid);
1752 
1753 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1754 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1755 	     hdr->rtt != RESERVED_ITT)) {
1756 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1757 		hdr->rtt = RESERVED_ITT;
1758 	}
1759 
1760 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1761 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1762 		pr_err("Task Management Request TASK_REASSIGN not"
1763 			" issued as immediate command, bad iSCSI Initiator"
1764 				"implementation\n");
1765 		return iscsit_add_reject_cmd(cmd,
1766 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1767 	}
1768 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1769 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1770 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1771 
1772 	cmd->data_direction = DMA_NONE;
1773 
1774 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1775 	if (!cmd->tmr_req) {
1776 		pr_err("Unable to allocate memory for"
1777 			" Task Management command!\n");
1778 		return iscsit_add_reject_cmd(cmd,
1779 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1780 					     buf);
1781 	}
1782 
1783 	/*
1784 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1785 	 * LIO-Target $FABRIC_MOD
1786 	 */
1787 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1788 
1789 		u8 tcm_function;
1790 		int ret;
1791 
1792 		transport_init_se_cmd(&cmd->se_cmd,
1793 				      &lio_target_fabric_configfs->tf_ops,
1794 				      conn->sess->se_sess, 0, DMA_NONE,
1795 				      MSG_SIMPLE_TAG, cmd->sense_buffer + 2);
1796 
1797 		target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
1798 		sess_ref = true;
1799 
1800 		switch (function) {
1801 		case ISCSI_TM_FUNC_ABORT_TASK:
1802 			tcm_function = TMR_ABORT_TASK;
1803 			break;
1804 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1805 			tcm_function = TMR_ABORT_TASK_SET;
1806 			break;
1807 		case ISCSI_TM_FUNC_CLEAR_ACA:
1808 			tcm_function = TMR_CLEAR_ACA;
1809 			break;
1810 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1811 			tcm_function = TMR_CLEAR_TASK_SET;
1812 			break;
1813 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1814 			tcm_function = TMR_LUN_RESET;
1815 			break;
1816 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1817 			tcm_function = TMR_TARGET_WARM_RESET;
1818 			break;
1819 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1820 			tcm_function = TMR_TARGET_COLD_RESET;
1821 			break;
1822 		default:
1823 			pr_err("Unknown iSCSI TMR Function:"
1824 			       " 0x%02x\n", function);
1825 			return iscsit_add_reject_cmd(cmd,
1826 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1827 		}
1828 
1829 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1830 					 tcm_function, GFP_KERNEL);
1831 		if (ret < 0)
1832 			return iscsit_add_reject_cmd(cmd,
1833 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1834 
1835 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1836 	}
1837 
1838 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1839 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1840 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1841 	cmd->init_task_tag	= hdr->itt;
1842 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1843 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1844 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1845 	se_tmr			= cmd->se_cmd.se_tmr_req;
1846 	tmr_req			= cmd->tmr_req;
1847 	/*
1848 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1849 	 */
1850 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1851 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1852 					       scsilun_to_int(&hdr->lun));
1853 		if (ret < 0) {
1854 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1855 			goto attach;
1856 		}
1857 	}
1858 
1859 	switch (function) {
1860 	case ISCSI_TM_FUNC_ABORT_TASK:
1861 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1862 		if (se_tmr->response)
1863 			goto attach;
1864 		break;
1865 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1866 	case ISCSI_TM_FUNC_CLEAR_ACA:
1867 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1868 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1869 		break;
1870 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1871 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1872 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1873 			goto attach;
1874 		}
1875 		break;
1876 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1877 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1878 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1879 			goto attach;
1880 		}
1881 		break;
1882 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1883 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1884 		/*
1885 		 * Perform sanity checks on the ExpDataSN only if the
1886 		 * TASK_REASSIGN was successful.
1887 		 */
1888 		if (se_tmr->response)
1889 			break;
1890 
1891 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1892 			return iscsit_add_reject_cmd(cmd,
1893 					ISCSI_REASON_BOOKMARK_INVALID, buf);
1894 		break;
1895 	default:
1896 		pr_err("Unknown TMR function: 0x%02x, protocol"
1897 			" error.\n", function);
1898 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1899 		goto attach;
1900 	}
1901 
1902 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1903 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1904 		se_tmr->call_transport = 1;
1905 attach:
1906 	spin_lock_bh(&conn->cmd_lock);
1907 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1908 	spin_unlock_bh(&conn->cmd_lock);
1909 
1910 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1911 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1912 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1913 			out_of_order_cmdsn = 1;
1914 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1915 			return 0;
1916 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1917 			return -1;
1918 	}
1919 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1920 
1921 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1922 		return 0;
1923 	/*
1924 	 * Found the referenced task, send to transport for processing.
1925 	 */
1926 	if (se_tmr->call_transport)
1927 		return transport_generic_handle_tmr(&cmd->se_cmd);
1928 
1929 	/*
1930 	 * Could not find the referenced LUN, task, or Task Management
1931 	 * command not authorized or supported.  Change state and
1932 	 * let the tx_thread send the response.
1933 	 *
1934 	 * For connection recovery, this is also the default action for
1935 	 * TMR TASK_REASSIGN.
1936 	 */
1937 	if (sess_ref) {
1938 		pr_debug("Handle TMR, using sess_ref=true check\n");
1939 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1940 	}
1941 
1942 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1943 	return 0;
1944 }
1945 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
1946 
1947 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1948 int
1949 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1950 		      struct iscsi_text *hdr)
1951 {
1952 	u32 payload_length = ntoh24(hdr->dlength);
1953 
1954 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1955 		pr_err("Unable to accept text parameter length: %u"
1956 			"greater than MaxXmitDataSegmentLength %u.\n",
1957 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1958 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1959 					 (unsigned char *)hdr);
1960 	}
1961 
1962 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1963 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1964 		hdr->exp_statsn, payload_length);
1965 
1966 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1967 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1968 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1969 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
1970 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1971 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1972 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1973 	cmd->data_direction	= DMA_NONE;
1974 
1975 	return 0;
1976 }
1977 EXPORT_SYMBOL(iscsit_setup_text_cmd);
1978 
1979 int
1980 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1981 			struct iscsi_text *hdr)
1982 {
1983 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
1984 	int cmdsn_ret;
1985 
1986 	if (!text_in) {
1987 		pr_err("Unable to locate text_in buffer for sendtargets"
1988 		       " discovery\n");
1989 		goto reject;
1990 	}
1991 	if (strncmp("SendTargets", text_in, 11) != 0) {
1992 		pr_err("Received Text Data that is not"
1993 			" SendTargets, cannot continue.\n");
1994 		goto reject;
1995 	}
1996 	text_ptr = strchr(text_in, '=');
1997 	if (!text_ptr) {
1998 		pr_err("No \"=\" separator found in Text Data,"
1999 			"  cannot continue.\n");
2000 		goto reject;
2001 	}
2002 	if (!strncmp("=All", text_ptr, 4)) {
2003 		cmd->cmd_flags |= IFC_SENDTARGETS_ALL;
2004 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2005 		   !strncmp("=eui.", text_ptr, 5)) {
2006 		cmd->cmd_flags |= IFC_SENDTARGETS_SINGLE;
2007 	} else {
2008 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2009 		goto reject;
2010 	}
2011 
2012 	spin_lock_bh(&conn->cmd_lock);
2013 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2014 	spin_unlock_bh(&conn->cmd_lock);
2015 
2016 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2017 
2018 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2019 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2020 				(unsigned char *)hdr, hdr->cmdsn);
2021 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2022 			return -1;
2023 
2024 		return 0;
2025 	}
2026 
2027 	return iscsit_execute_cmd(cmd, 0);
2028 
2029 reject:
2030 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2031 				 (unsigned char *)hdr);
2032 }
2033 EXPORT_SYMBOL(iscsit_process_text_cmd);
2034 
2035 static int
2036 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2037 		       unsigned char *buf)
2038 {
2039 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2040 	char *text_in = NULL;
2041 	u32 payload_length = ntoh24(hdr->dlength);
2042 	int rx_size, rc;
2043 
2044 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2045 	if (rc < 0)
2046 		return 0;
2047 
2048 	rx_size = payload_length;
2049 	if (payload_length) {
2050 		u32 checksum = 0, data_crc = 0;
2051 		u32 padding = 0, pad_bytes = 0;
2052 		int niov = 0, rx_got;
2053 		struct kvec iov[3];
2054 
2055 		text_in = kzalloc(payload_length, GFP_KERNEL);
2056 		if (!text_in) {
2057 			pr_err("Unable to allocate memory for"
2058 				" incoming text parameters\n");
2059 			goto reject;
2060 		}
2061 		cmd->text_in_ptr = text_in;
2062 
2063 		memset(iov, 0, 3 * sizeof(struct kvec));
2064 		iov[niov].iov_base	= text_in;
2065 		iov[niov++].iov_len	= payload_length;
2066 
2067 		padding = ((-payload_length) & 3);
2068 		if (padding != 0) {
2069 			iov[niov].iov_base = &pad_bytes;
2070 			iov[niov++].iov_len  = padding;
2071 			rx_size += padding;
2072 			pr_debug("Receiving %u additional bytes"
2073 					" for padding.\n", padding);
2074 		}
2075 		if (conn->conn_ops->DataDigest) {
2076 			iov[niov].iov_base	= &checksum;
2077 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2078 			rx_size += ISCSI_CRC_LEN;
2079 		}
2080 
2081 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2082 		if (rx_got != rx_size)
2083 			goto reject;
2084 
2085 		if (conn->conn_ops->DataDigest) {
2086 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
2087 					text_in, payload_length,
2088 					padding, (u8 *)&pad_bytes,
2089 					(u8 *)&data_crc);
2090 
2091 			if (checksum != data_crc) {
2092 				pr_err("Text data CRC32C DataDigest"
2093 					" 0x%08x does not match computed"
2094 					" 0x%08x\n", checksum, data_crc);
2095 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2096 					pr_err("Unable to recover from"
2097 					" Text Data digest failure while in"
2098 						" ERL=0.\n");
2099 					goto reject;
2100 				} else {
2101 					/*
2102 					 * Silently drop this PDU and let the
2103 					 * initiator plug the CmdSN gap.
2104 					 */
2105 					pr_debug("Dropping Text"
2106 					" Command CmdSN: 0x%08x due to"
2107 					" DataCRC error.\n", hdr->cmdsn);
2108 					kfree(text_in);
2109 					return 0;
2110 				}
2111 			} else {
2112 				pr_debug("Got CRC32C DataDigest"
2113 					" 0x%08x for %u bytes of text data.\n",
2114 						checksum, payload_length);
2115 			}
2116 		}
2117 		text_in[payload_length - 1] = '\0';
2118 		pr_debug("Successfully read %d bytes of text"
2119 				" data.\n", payload_length);
2120 	}
2121 
2122 	return iscsit_process_text_cmd(conn, cmd, hdr);
2123 
2124 reject:
2125 	kfree(cmd->text_in_ptr);
2126 	cmd->text_in_ptr = NULL;
2127 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2128 }
2129 EXPORT_SYMBOL(iscsit_handle_text_cmd);
2130 
2131 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2132 {
2133 	struct iscsi_conn *conn_p;
2134 	struct iscsi_session *sess = conn->sess;
2135 
2136 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2137 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2138 
2139 	atomic_set(&sess->session_logout, 1);
2140 	atomic_set(&conn->conn_logout_remove, 1);
2141 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2142 
2143 	iscsit_inc_conn_usage_count(conn);
2144 	iscsit_inc_session_usage_count(sess);
2145 
2146 	spin_lock_bh(&sess->conn_lock);
2147 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2148 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2149 			continue;
2150 
2151 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2152 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2153 	}
2154 	spin_unlock_bh(&sess->conn_lock);
2155 
2156 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2157 
2158 	return 0;
2159 }
2160 
2161 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2162 {
2163 	struct iscsi_conn *l_conn;
2164 	struct iscsi_session *sess = conn->sess;
2165 
2166 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2167 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2168 
2169 	/*
2170 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2171 	 * can arrive on a connection with a differing CID.
2172 	 */
2173 	if (conn->cid == cmd->logout_cid) {
2174 		spin_lock_bh(&conn->state_lock);
2175 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2176 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2177 
2178 		atomic_set(&conn->conn_logout_remove, 1);
2179 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2180 		iscsit_inc_conn_usage_count(conn);
2181 
2182 		spin_unlock_bh(&conn->state_lock);
2183 	} else {
2184 		/*
2185 		 * Handle all different cid CLOSECONNECTION requests in
2186 		 * iscsit_logout_post_handler_diffcid() as to give enough
2187 		 * time for any non immediate command's CmdSN to be
2188 		 * acknowledged on the connection in question.
2189 		 *
2190 		 * Here we simply make sure the CID is still around.
2191 		 */
2192 		l_conn = iscsit_get_conn_from_cid(sess,
2193 				cmd->logout_cid);
2194 		if (!l_conn) {
2195 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2196 			iscsit_add_cmd_to_response_queue(cmd, conn,
2197 					cmd->i_state);
2198 			return 0;
2199 		}
2200 
2201 		iscsit_dec_conn_usage_count(l_conn);
2202 	}
2203 
2204 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2205 
2206 	return 0;
2207 }
2208 
2209 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2210 {
2211 	struct iscsi_session *sess = conn->sess;
2212 
2213 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2214 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2215 
2216 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2217 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2218 			" while ERL!=2.\n");
2219 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2220 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2221 		return 0;
2222 	}
2223 
2224 	if (conn->cid == cmd->logout_cid) {
2225 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2226 			" with CID: %hu on CID: %hu, implementation error.\n",
2227 				cmd->logout_cid, conn->cid);
2228 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2229 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2230 		return 0;
2231 	}
2232 
2233 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2234 
2235 	return 0;
2236 }
2237 
2238 int
2239 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2240 			unsigned char *buf)
2241 {
2242 	int cmdsn_ret, logout_remove = 0;
2243 	u8 reason_code = 0;
2244 	struct iscsi_logout *hdr;
2245 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2246 
2247 	hdr			= (struct iscsi_logout *) buf;
2248 	reason_code		= (hdr->flags & 0x7f);
2249 
2250 	if (tiqn) {
2251 		spin_lock(&tiqn->logout_stats.lock);
2252 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2253 			tiqn->logout_stats.normal_logouts++;
2254 		else
2255 			tiqn->logout_stats.abnormal_logouts++;
2256 		spin_unlock(&tiqn->logout_stats.lock);
2257 	}
2258 
2259 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2260 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2261 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2262 		hdr->cid, conn->cid);
2263 
2264 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2265 		pr_err("Received logout request on connection that"
2266 			" is not in logged in state, ignoring request.\n");
2267 		iscsit_free_cmd(cmd, false);
2268 		return 0;
2269 	}
2270 
2271 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2272 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2273 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2274 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2275 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2276 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2277 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2278 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2279 	cmd->logout_reason      = reason_code;
2280 	cmd->data_direction     = DMA_NONE;
2281 
2282 	/*
2283 	 * We need to sleep in these cases (by returning 1) until the Logout
2284 	 * Response gets sent in the tx thread.
2285 	 */
2286 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2287 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2288 	    be16_to_cpu(hdr->cid) == conn->cid))
2289 		logout_remove = 1;
2290 
2291 	spin_lock_bh(&conn->cmd_lock);
2292 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2293 	spin_unlock_bh(&conn->cmd_lock);
2294 
2295 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2296 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2297 
2298 	/*
2299 	 * Immediate commands are executed, well, immediately.
2300 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2301 	 */
2302 	if (cmd->immediate_cmd) {
2303 		int ret = iscsit_execute_cmd(cmd, 0);
2304 
2305 		if (ret < 0)
2306 			return ret;
2307 	} else {
2308 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2309 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2310 			logout_remove = 0;
2311 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2312 			return -1;
2313 	}
2314 
2315 	return logout_remove;
2316 }
2317 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2318 
2319 static int iscsit_handle_snack(
2320 	struct iscsi_conn *conn,
2321 	unsigned char *buf)
2322 {
2323 	struct iscsi_snack *hdr;
2324 
2325 	hdr			= (struct iscsi_snack *) buf;
2326 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2327 
2328 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2329 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2330 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2331 			hdr->begrun, hdr->runlength, conn->cid);
2332 
2333 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2334 		pr_err("Initiator sent SNACK request while in"
2335 			" ErrorRecoveryLevel=0.\n");
2336 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2337 					 buf);
2338 	}
2339 	/*
2340 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2341 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2342 	 */
2343 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2344 	case 0:
2345 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2346 			hdr->itt,
2347 			be32_to_cpu(hdr->ttt),
2348 			be32_to_cpu(hdr->begrun),
2349 			be32_to_cpu(hdr->runlength));
2350 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2351 		return iscsit_handle_status_snack(conn, hdr->itt,
2352 			be32_to_cpu(hdr->ttt),
2353 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2354 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2355 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2356 			be32_to_cpu(hdr->begrun),
2357 			be32_to_cpu(hdr->runlength));
2358 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2359 		/* FIXME: Support R-Data SNACK */
2360 		pr_err("R-Data SNACK Not Supported.\n");
2361 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2362 					 buf);
2363 	default:
2364 		pr_err("Unknown SNACK type 0x%02x, protocol"
2365 			" error.\n", hdr->flags & 0x0f);
2366 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2367 					 buf);
2368 	}
2369 
2370 	return 0;
2371 }
2372 
2373 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2374 {
2375 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2376 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2377 		wait_for_completion_interruptible_timeout(
2378 					&conn->rx_half_close_comp,
2379 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2380 	}
2381 }
2382 
2383 static int iscsit_handle_immediate_data(
2384 	struct iscsi_cmd *cmd,
2385 	struct iscsi_scsi_req *hdr,
2386 	u32 length)
2387 {
2388 	int iov_ret, rx_got = 0, rx_size = 0;
2389 	u32 checksum, iov_count = 0, padding = 0;
2390 	struct iscsi_conn *conn = cmd->conn;
2391 	struct kvec *iov;
2392 
2393 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2394 	if (iov_ret < 0)
2395 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2396 
2397 	rx_size = length;
2398 	iov_count = iov_ret;
2399 	iov = &cmd->iov_data[0];
2400 
2401 	padding = ((-length) & 3);
2402 	if (padding != 0) {
2403 		iov[iov_count].iov_base	= cmd->pad_bytes;
2404 		iov[iov_count++].iov_len = padding;
2405 		rx_size += padding;
2406 	}
2407 
2408 	if (conn->conn_ops->DataDigest) {
2409 		iov[iov_count].iov_base		= &checksum;
2410 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2411 		rx_size += ISCSI_CRC_LEN;
2412 	}
2413 
2414 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2415 
2416 	iscsit_unmap_iovec(cmd);
2417 
2418 	if (rx_got != rx_size) {
2419 		iscsit_rx_thread_wait_for_tcp(conn);
2420 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2421 	}
2422 
2423 	if (conn->conn_ops->DataDigest) {
2424 		u32 data_crc;
2425 
2426 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2427 						    cmd->write_data_done, length, padding,
2428 						    cmd->pad_bytes);
2429 
2430 		if (checksum != data_crc) {
2431 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2432 				" does not match computed 0x%08x\n", checksum,
2433 				data_crc);
2434 
2435 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2436 				pr_err("Unable to recover from"
2437 					" Immediate Data digest failure while"
2438 					" in ERL=0.\n");
2439 				iscsit_reject_cmd(cmd,
2440 						ISCSI_REASON_DATA_DIGEST_ERROR,
2441 						(unsigned char *)hdr);
2442 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2443 			} else {
2444 				iscsit_reject_cmd(cmd,
2445 						ISCSI_REASON_DATA_DIGEST_ERROR,
2446 						(unsigned char *)hdr);
2447 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2448 			}
2449 		} else {
2450 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2451 				" %u bytes of Immediate Data\n", checksum,
2452 				length);
2453 		}
2454 	}
2455 
2456 	cmd->write_data_done += length;
2457 
2458 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2459 		spin_lock_bh(&cmd->istate_lock);
2460 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2461 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2462 		spin_unlock_bh(&cmd->istate_lock);
2463 	}
2464 
2465 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2466 }
2467 
2468 /*
2469  *	Called with sess->conn_lock held.
2470  */
2471 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2472 	with active network interface */
2473 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2474 {
2475 	struct iscsi_cmd *cmd;
2476 	struct iscsi_conn *conn_p;
2477 
2478 	/*
2479 	 * Only send a Asynchronous Message on connections whos network
2480 	 * interface is still functional.
2481 	 */
2482 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2483 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2484 			iscsit_inc_conn_usage_count(conn_p);
2485 			break;
2486 		}
2487 	}
2488 
2489 	if (!conn_p)
2490 		return;
2491 
2492 	cmd = iscsit_allocate_cmd(conn_p, GFP_ATOMIC);
2493 	if (!cmd) {
2494 		iscsit_dec_conn_usage_count(conn_p);
2495 		return;
2496 	}
2497 
2498 	cmd->logout_cid = conn->cid;
2499 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2500 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2501 
2502 	spin_lock_bh(&conn_p->cmd_lock);
2503 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2504 	spin_unlock_bh(&conn_p->cmd_lock);
2505 
2506 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2507 	iscsit_dec_conn_usage_count(conn_p);
2508 }
2509 
2510 static int iscsit_send_conn_drop_async_message(
2511 	struct iscsi_cmd *cmd,
2512 	struct iscsi_conn *conn)
2513 {
2514 	struct iscsi_async *hdr;
2515 
2516 	cmd->tx_size = ISCSI_HDR_LEN;
2517 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2518 
2519 	hdr			= (struct iscsi_async *) cmd->pdu;
2520 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2521 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2522 	cmd->init_task_tag	= RESERVED_ITT;
2523 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2524 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2525 	cmd->stat_sn		= conn->stat_sn++;
2526 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2527 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2528 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2529 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2530 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2531 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2532 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2533 
2534 	if (conn->conn_ops->HeaderDigest) {
2535 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2536 
2537 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2538 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2539 
2540 		cmd->tx_size += ISCSI_CRC_LEN;
2541 		pr_debug("Attaching CRC32C HeaderDigest to"
2542 			" Async Message 0x%08x\n", *header_digest);
2543 	}
2544 
2545 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2546 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2547 	cmd->iov_misc_count		= 1;
2548 
2549 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2550 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2551 			cmd->logout_cid, conn->cid);
2552 	return 0;
2553 }
2554 
2555 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2556 {
2557 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2558 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2559 		wait_for_completion_interruptible_timeout(
2560 					&conn->tx_half_close_comp,
2561 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2562 	}
2563 }
2564 
2565 static void
2566 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2567 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2568 			bool set_statsn)
2569 {
2570 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2571 	hdr->flags		= datain->flags;
2572 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2573 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2574 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2575 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2576 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2577 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2578 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2579 		}
2580 	}
2581 	hton24(hdr->dlength, datain->length);
2582 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2583 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2584 				(struct scsi_lun *)&hdr->lun);
2585 	else
2586 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2587 
2588 	hdr->itt		= cmd->init_task_tag;
2589 
2590 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2591 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2592 	else
2593 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2594 	if (set_statsn)
2595 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2596 	else
2597 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2598 
2599 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2600 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2601 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2602 	hdr->offset		= cpu_to_be32(datain->offset);
2603 
2604 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2605 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2606 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2607 		ntohl(hdr->offset), datain->length, conn->cid);
2608 }
2609 
2610 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2611 {
2612 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2613 	struct iscsi_datain datain;
2614 	struct iscsi_datain_req *dr;
2615 	struct kvec *iov;
2616 	u32 iov_count = 0, tx_size = 0;
2617 	int eodr = 0, ret, iov_ret;
2618 	bool set_statsn = false;
2619 
2620 	memset(&datain, 0, sizeof(struct iscsi_datain));
2621 	dr = iscsit_get_datain_values(cmd, &datain);
2622 	if (!dr) {
2623 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2624 				cmd->init_task_tag);
2625 		return -1;
2626 	}
2627 	/*
2628 	 * Be paranoid and double check the logic for now.
2629 	 */
2630 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2631 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2632 			" datain.length: %u exceeds cmd->data_length: %u\n",
2633 			cmd->init_task_tag, datain.offset, datain.length,
2634 			cmd->se_cmd.data_length);
2635 		return -1;
2636 	}
2637 
2638 	spin_lock_bh(&conn->sess->session_stats_lock);
2639 	conn->sess->tx_data_octets += datain.length;
2640 	if (conn->sess->se_sess->se_node_acl) {
2641 		spin_lock(&conn->sess->se_sess->se_node_acl->stats_lock);
2642 		conn->sess->se_sess->se_node_acl->read_bytes += datain.length;
2643 		spin_unlock(&conn->sess->se_sess->se_node_acl->stats_lock);
2644 	}
2645 	spin_unlock_bh(&conn->sess->session_stats_lock);
2646 	/*
2647 	 * Special case for successfully execution w/ both DATAIN
2648 	 * and Sense Data.
2649 	 */
2650 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2651 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2652 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2653 	else {
2654 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2655 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2656 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2657 			cmd->stat_sn = conn->stat_sn++;
2658 			set_statsn = true;
2659 		} else if (dr->dr_complete ==
2660 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2661 			set_statsn = true;
2662 	}
2663 
2664 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2665 
2666 	iov = &cmd->iov_data[0];
2667 	iov[iov_count].iov_base	= cmd->pdu;
2668 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2669 	tx_size += ISCSI_HDR_LEN;
2670 
2671 	if (conn->conn_ops->HeaderDigest) {
2672 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2673 
2674 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
2675 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2676 
2677 		iov[0].iov_len += ISCSI_CRC_LEN;
2678 		tx_size += ISCSI_CRC_LEN;
2679 
2680 		pr_debug("Attaching CRC32 HeaderDigest"
2681 			" for DataIN PDU 0x%08x\n", *header_digest);
2682 	}
2683 
2684 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
2685 				datain.offset, datain.length);
2686 	if (iov_ret < 0)
2687 		return -1;
2688 
2689 	iov_count += iov_ret;
2690 	tx_size += datain.length;
2691 
2692 	cmd->padding = ((-datain.length) & 3);
2693 	if (cmd->padding) {
2694 		iov[iov_count].iov_base		= cmd->pad_bytes;
2695 		iov[iov_count++].iov_len	= cmd->padding;
2696 		tx_size += cmd->padding;
2697 
2698 		pr_debug("Attaching %u padding bytes\n",
2699 				cmd->padding);
2700 	}
2701 	if (conn->conn_ops->DataDigest) {
2702 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2703 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2704 
2705 		iov[iov_count].iov_base	= &cmd->data_crc;
2706 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2707 		tx_size += ISCSI_CRC_LEN;
2708 
2709 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2710 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2711 	}
2712 
2713 	cmd->iov_data_count = iov_count;
2714 	cmd->tx_size = tx_size;
2715 
2716 	/* sendpage is preferred but can't insert markers */
2717 	if (!conn->conn_ops->IFMarker)
2718 		ret = iscsit_fe_sendpage_sg(cmd, conn);
2719 	else
2720 		ret = iscsit_send_tx_data(cmd, conn, 0);
2721 
2722 	iscsit_unmap_iovec(cmd);
2723 
2724 	if (ret < 0) {
2725 		iscsit_tx_thread_wait_for_tcp(conn);
2726 		return ret;
2727 	}
2728 
2729 	if (dr->dr_complete) {
2730 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2731 				2 : 1;
2732 		iscsit_free_datain_req(cmd, dr);
2733 	}
2734 
2735 	return eodr;
2736 }
2737 
2738 int
2739 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2740 			struct iscsi_logout_rsp *hdr)
2741 {
2742 	struct iscsi_conn *logout_conn = NULL;
2743 	struct iscsi_conn_recovery *cr = NULL;
2744 	struct iscsi_session *sess = conn->sess;
2745 	/*
2746 	 * The actual shutting down of Sessions and/or Connections
2747 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2748 	 * is done in scsi_logout_post_handler().
2749 	 */
2750 	switch (cmd->logout_reason) {
2751 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2752 		pr_debug("iSCSI session logout successful, setting"
2753 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2754 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2755 		break;
2756 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2757 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2758 			break;
2759 		/*
2760 		 * For CLOSECONNECTION logout requests carrying
2761 		 * a matching logout CID -> local CID, the reference
2762 		 * for the local CID will have been incremented in
2763 		 * iscsi_logout_closeconnection().
2764 		 *
2765 		 * For CLOSECONNECTION logout requests carrying
2766 		 * a different CID than the connection it arrived
2767 		 * on, the connection responding to cmd->logout_cid
2768 		 * is stopped in iscsit_logout_post_handler_diffcid().
2769 		 */
2770 
2771 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2772 			" successful.\n", cmd->logout_cid, conn->cid);
2773 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2774 		break;
2775 	case ISCSI_LOGOUT_REASON_RECOVERY:
2776 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2777 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2778 			break;
2779 		/*
2780 		 * If the connection is still active from our point of view
2781 		 * force connection recovery to occur.
2782 		 */
2783 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2784 				cmd->logout_cid);
2785 		if (logout_conn) {
2786 			iscsit_connection_reinstatement_rcfr(logout_conn);
2787 			iscsit_dec_conn_usage_count(logout_conn);
2788 		}
2789 
2790 		cr = iscsit_get_inactive_connection_recovery_entry(
2791 				conn->sess, cmd->logout_cid);
2792 		if (!cr) {
2793 			pr_err("Unable to locate CID: %hu for"
2794 			" REMOVECONNFORRECOVERY Logout Request.\n",
2795 				cmd->logout_cid);
2796 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2797 			break;
2798 		}
2799 
2800 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2801 
2802 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2803 			" for recovery for CID: %hu on CID: %hu successful.\n",
2804 				cmd->logout_cid, conn->cid);
2805 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2806 		break;
2807 	default:
2808 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2809 				cmd->logout_reason);
2810 		return -1;
2811 	}
2812 
2813 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2814 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2815 	hdr->response		= cmd->logout_response;
2816 	hdr->itt		= cmd->init_task_tag;
2817 	cmd->stat_sn		= conn->stat_sn++;
2818 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2819 
2820 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2821 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2822 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2823 
2824 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2825 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2826 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2827 		cmd->logout_cid, conn->cid);
2828 
2829 	return 0;
2830 }
2831 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2832 
2833 static int
2834 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2835 {
2836 	struct kvec *iov;
2837 	int niov = 0, tx_size, rc;
2838 
2839 	rc = iscsit_build_logout_rsp(cmd, conn,
2840 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2841 	if (rc < 0)
2842 		return rc;
2843 
2844 	tx_size = ISCSI_HDR_LEN;
2845 	iov = &cmd->iov_misc[0];
2846 	iov[niov].iov_base	= cmd->pdu;
2847 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2848 
2849 	if (conn->conn_ops->HeaderDigest) {
2850 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2851 
2852 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, &cmd->pdu[0],
2853 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2854 
2855 		iov[0].iov_len += ISCSI_CRC_LEN;
2856 		tx_size += ISCSI_CRC_LEN;
2857 		pr_debug("Attaching CRC32C HeaderDigest to"
2858 			" Logout Response 0x%08x\n", *header_digest);
2859 	}
2860 	cmd->iov_misc_count = niov;
2861 	cmd->tx_size = tx_size;
2862 
2863 	return 0;
2864 }
2865 
2866 void
2867 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2868 		       struct iscsi_nopin *hdr, bool nopout_response)
2869 {
2870 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2871 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2872         hton24(hdr->dlength, cmd->buf_ptr_size);
2873 	if (nopout_response)
2874 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2875 	hdr->itt		= cmd->init_task_tag;
2876 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2877 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2878 				  conn->stat_sn;
2879 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2880 
2881 	if (nopout_response)
2882 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2883 
2884 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2885 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2886 
2887 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2888 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2889 		"Solicitied" : "Unsolicitied", cmd->init_task_tag,
2890 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2891 }
2892 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2893 
2894 /*
2895  *	Unsolicited NOPIN, either requesting a response or not.
2896  */
2897 static int iscsit_send_unsolicited_nopin(
2898 	struct iscsi_cmd *cmd,
2899 	struct iscsi_conn *conn,
2900 	int want_response)
2901 {
2902 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2903 	int tx_size = ISCSI_HDR_LEN, ret;
2904 
2905 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
2906 
2907 	if (conn->conn_ops->HeaderDigest) {
2908 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2909 
2910 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2911 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2912 
2913 		tx_size += ISCSI_CRC_LEN;
2914 		pr_debug("Attaching CRC32C HeaderDigest to"
2915 			" NopIN 0x%08x\n", *header_digest);
2916 	}
2917 
2918 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2919 	cmd->iov_misc[0].iov_len	= tx_size;
2920 	cmd->iov_misc_count	= 1;
2921 	cmd->tx_size		= tx_size;
2922 
2923 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2924 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2925 
2926 	ret = iscsit_send_tx_data(cmd, conn, 1);
2927 	if (ret < 0) {
2928 		iscsit_tx_thread_wait_for_tcp(conn);
2929 		return ret;
2930 	}
2931 
2932 	spin_lock_bh(&cmd->istate_lock);
2933 	cmd->i_state = want_response ?
2934 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2935 	spin_unlock_bh(&cmd->istate_lock);
2936 
2937 	return 0;
2938 }
2939 
2940 static int
2941 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2942 {
2943 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2944 	struct kvec *iov;
2945 	u32 padding = 0;
2946 	int niov = 0, tx_size;
2947 
2948 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
2949 
2950 	tx_size = ISCSI_HDR_LEN;
2951 	iov = &cmd->iov_misc[0];
2952 	iov[niov].iov_base	= cmd->pdu;
2953 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2954 
2955 	if (conn->conn_ops->HeaderDigest) {
2956 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2957 
2958 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2959 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2960 
2961 		iov[0].iov_len += ISCSI_CRC_LEN;
2962 		tx_size += ISCSI_CRC_LEN;
2963 		pr_debug("Attaching CRC32C HeaderDigest"
2964 			" to NopIn 0x%08x\n", *header_digest);
2965 	}
2966 
2967 	/*
2968 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2969 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2970 	 */
2971 	if (cmd->buf_ptr_size) {
2972 		iov[niov].iov_base	= cmd->buf_ptr;
2973 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2974 		tx_size += cmd->buf_ptr_size;
2975 
2976 		pr_debug("Echoing back %u bytes of ping"
2977 			" data.\n", cmd->buf_ptr_size);
2978 
2979 		padding = ((-cmd->buf_ptr_size) & 3);
2980 		if (padding != 0) {
2981 			iov[niov].iov_base = &cmd->pad_bytes;
2982 			iov[niov++].iov_len = padding;
2983 			tx_size += padding;
2984 			pr_debug("Attaching %u additional"
2985 				" padding bytes.\n", padding);
2986 		}
2987 		if (conn->conn_ops->DataDigest) {
2988 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
2989 				cmd->buf_ptr, cmd->buf_ptr_size,
2990 				padding, (u8 *)&cmd->pad_bytes,
2991 				(u8 *)&cmd->data_crc);
2992 
2993 			iov[niov].iov_base = &cmd->data_crc;
2994 			iov[niov++].iov_len = ISCSI_CRC_LEN;
2995 			tx_size += ISCSI_CRC_LEN;
2996 			pr_debug("Attached DataDigest for %u"
2997 				" bytes of ping data, CRC 0x%08x\n",
2998 				cmd->buf_ptr_size, cmd->data_crc);
2999 		}
3000 	}
3001 
3002 	cmd->iov_misc_count = niov;
3003 	cmd->tx_size = tx_size;
3004 
3005 	return 0;
3006 }
3007 
3008 static int iscsit_send_r2t(
3009 	struct iscsi_cmd *cmd,
3010 	struct iscsi_conn *conn)
3011 {
3012 	int tx_size = 0;
3013 	struct iscsi_r2t *r2t;
3014 	struct iscsi_r2t_rsp *hdr;
3015 	int ret;
3016 
3017 	r2t = iscsit_get_r2t_from_list(cmd);
3018 	if (!r2t)
3019 		return -1;
3020 
3021 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3022 	memset(hdr, 0, ISCSI_HDR_LEN);
3023 	hdr->opcode		= ISCSI_OP_R2T;
3024 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3025 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3026 			(struct scsi_lun *)&hdr->lun);
3027 	hdr->itt		= cmd->init_task_tag;
3028 	spin_lock_bh(&conn->sess->ttt_lock);
3029 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
3030 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
3031 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
3032 	spin_unlock_bh(&conn->sess->ttt_lock);
3033 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3034 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3035 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3036 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3037 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3038 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3039 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3040 
3041 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3042 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3043 	tx_size += ISCSI_HDR_LEN;
3044 
3045 	if (conn->conn_ops->HeaderDigest) {
3046 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3047 
3048 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3049 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3050 
3051 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3052 		tx_size += ISCSI_CRC_LEN;
3053 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
3054 			" PDU 0x%08x\n", *header_digest);
3055 	}
3056 
3057 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3058 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3059 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3060 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3061 			r2t->offset, r2t->xfer_len, conn->cid);
3062 
3063 	cmd->iov_misc_count = 1;
3064 	cmd->tx_size = tx_size;
3065 
3066 	spin_lock_bh(&cmd->r2t_lock);
3067 	r2t->sent_r2t = 1;
3068 	spin_unlock_bh(&cmd->r2t_lock);
3069 
3070 	ret = iscsit_send_tx_data(cmd, conn, 1);
3071 	if (ret < 0) {
3072 		iscsit_tx_thread_wait_for_tcp(conn);
3073 		return ret;
3074 	}
3075 
3076 	spin_lock_bh(&cmd->dataout_timeout_lock);
3077 	iscsit_start_dataout_timer(cmd, conn);
3078 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3079 
3080 	return 0;
3081 }
3082 
3083 /*
3084  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3085  *		connection recovery.
3086  */
3087 int iscsit_build_r2ts_for_cmd(
3088 	struct iscsi_conn *conn,
3089 	struct iscsi_cmd *cmd,
3090 	bool recovery)
3091 {
3092 	int first_r2t = 1;
3093 	u32 offset = 0, xfer_len = 0;
3094 
3095 	spin_lock_bh(&cmd->r2t_lock);
3096 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3097 		spin_unlock_bh(&cmd->r2t_lock);
3098 		return 0;
3099 	}
3100 
3101 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3102 	    !recovery)
3103 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3104 
3105 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3106 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3107 			offset = cmd->r2t_offset;
3108 
3109 			if (first_r2t && recovery) {
3110 				int new_data_end = offset +
3111 					conn->sess->sess_ops->MaxBurstLength -
3112 					cmd->next_burst_len;
3113 
3114 				if (new_data_end > cmd->se_cmd.data_length)
3115 					xfer_len = cmd->se_cmd.data_length - offset;
3116 				else
3117 					xfer_len =
3118 						conn->sess->sess_ops->MaxBurstLength -
3119 						cmd->next_burst_len;
3120 			} else {
3121 				int new_data_end = offset +
3122 					conn->sess->sess_ops->MaxBurstLength;
3123 
3124 				if (new_data_end > cmd->se_cmd.data_length)
3125 					xfer_len = cmd->se_cmd.data_length - offset;
3126 				else
3127 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3128 			}
3129 			cmd->r2t_offset += xfer_len;
3130 
3131 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3132 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3133 		} else {
3134 			struct iscsi_seq *seq;
3135 
3136 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3137 			if (!seq) {
3138 				spin_unlock_bh(&cmd->r2t_lock);
3139 				return -1;
3140 			}
3141 
3142 			offset = seq->offset;
3143 			xfer_len = seq->xfer_len;
3144 
3145 			if (cmd->seq_send_order == cmd->seq_count)
3146 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3147 		}
3148 		cmd->outstanding_r2ts++;
3149 		first_r2t = 0;
3150 
3151 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3152 			spin_unlock_bh(&cmd->r2t_lock);
3153 			return -1;
3154 		}
3155 
3156 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3157 			break;
3158 	}
3159 	spin_unlock_bh(&cmd->r2t_lock);
3160 
3161 	return 0;
3162 }
3163 
3164 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3165 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3166 {
3167 	if (inc_stat_sn)
3168 		cmd->stat_sn = conn->stat_sn++;
3169 
3170 	spin_lock_bh(&conn->sess->session_stats_lock);
3171 	conn->sess->rsp_pdus++;
3172 	spin_unlock_bh(&conn->sess->session_stats_lock);
3173 
3174 	memset(hdr, 0, ISCSI_HDR_LEN);
3175 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3176 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3177 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3178 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3179 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3180 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3181 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3182 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3183 	}
3184 	hdr->response		= cmd->iscsi_response;
3185 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3186 	hdr->itt		= cmd->init_task_tag;
3187 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3188 
3189 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3190 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3191 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3192 
3193 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3194 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3195 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3196 		cmd->se_cmd.scsi_status, conn->cid);
3197 }
3198 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3199 
3200 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3201 {
3202 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3203 	struct kvec *iov;
3204 	u32 padding = 0, tx_size = 0;
3205 	int iov_count = 0;
3206 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3207 
3208 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3209 
3210 	iov = &cmd->iov_misc[0];
3211 	iov[iov_count].iov_base	= cmd->pdu;
3212 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3213 	tx_size += ISCSI_HDR_LEN;
3214 
3215 	/*
3216 	 * Attach SENSE DATA payload to iSCSI Response PDU
3217 	 */
3218 	if (cmd->se_cmd.sense_buffer &&
3219 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3220 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3221 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3222 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3223 
3224 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3225 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3226 		iov[iov_count].iov_base	= cmd->sense_buffer;
3227 		iov[iov_count++].iov_len =
3228 				(cmd->se_cmd.scsi_sense_length + padding);
3229 		tx_size += cmd->se_cmd.scsi_sense_length;
3230 
3231 		if (padding) {
3232 			memset(cmd->sense_buffer +
3233 				cmd->se_cmd.scsi_sense_length, 0, padding);
3234 			tx_size += padding;
3235 			pr_debug("Adding %u bytes of padding to"
3236 				" SENSE.\n", padding);
3237 		}
3238 
3239 		if (conn->conn_ops->DataDigest) {
3240 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3241 				cmd->sense_buffer,
3242 				(cmd->se_cmd.scsi_sense_length + padding),
3243 				0, NULL, (u8 *)&cmd->data_crc);
3244 
3245 			iov[iov_count].iov_base    = &cmd->data_crc;
3246 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3247 			tx_size += ISCSI_CRC_LEN;
3248 
3249 			pr_debug("Attaching CRC32 DataDigest for"
3250 				" SENSE, %u bytes CRC 0x%08x\n",
3251 				(cmd->se_cmd.scsi_sense_length + padding),
3252 				cmd->data_crc);
3253 		}
3254 
3255 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3256 				" Response PDU\n",
3257 				cmd->se_cmd.scsi_sense_length);
3258 	}
3259 
3260 	if (conn->conn_ops->HeaderDigest) {
3261 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3262 
3263 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
3264 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3265 
3266 		iov[0].iov_len += ISCSI_CRC_LEN;
3267 		tx_size += ISCSI_CRC_LEN;
3268 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3269 				" PDU 0x%08x\n", *header_digest);
3270 	}
3271 
3272 	cmd->iov_misc_count = iov_count;
3273 	cmd->tx_size = tx_size;
3274 
3275 	return 0;
3276 }
3277 
3278 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3279 {
3280 	switch (se_tmr->response) {
3281 	case TMR_FUNCTION_COMPLETE:
3282 		return ISCSI_TMF_RSP_COMPLETE;
3283 	case TMR_TASK_DOES_NOT_EXIST:
3284 		return ISCSI_TMF_RSP_NO_TASK;
3285 	case TMR_LUN_DOES_NOT_EXIST:
3286 		return ISCSI_TMF_RSP_NO_LUN;
3287 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3288 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3289 	case TMR_FUNCTION_REJECTED:
3290 	default:
3291 		return ISCSI_TMF_RSP_REJECTED;
3292 	}
3293 }
3294 
3295 void
3296 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3297 			  struct iscsi_tm_rsp *hdr)
3298 {
3299 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3300 
3301 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3302 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3303 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3304 	hdr->itt		= cmd->init_task_tag;
3305 	cmd->stat_sn		= conn->stat_sn++;
3306 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3307 
3308 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3309 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3310 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3311 
3312 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3313 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3314 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3315 }
3316 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3317 
3318 static int
3319 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3320 {
3321 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3322 	u32 tx_size = 0;
3323 
3324 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3325 
3326 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3327 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3328 	tx_size += ISCSI_HDR_LEN;
3329 
3330 	if (conn->conn_ops->HeaderDigest) {
3331 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3332 
3333 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3334 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3335 
3336 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3337 		tx_size += ISCSI_CRC_LEN;
3338 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3339 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3340 	}
3341 
3342 	cmd->iov_misc_count = 1;
3343 	cmd->tx_size = tx_size;
3344 
3345 	return 0;
3346 }
3347 
3348 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3349 {
3350 	bool ret = false;
3351 
3352 	if (np->np_sockaddr.ss_family == AF_INET6) {
3353 		const struct sockaddr_in6 sin6 = {
3354 			.sin6_addr = IN6ADDR_ANY_INIT };
3355 		struct sockaddr_in6 *sock_in6 =
3356 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3357 
3358 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3359 				sin6.sin6_addr.s6_addr, 16))
3360 			ret = true;
3361 	} else {
3362 		struct sockaddr_in * sock_in =
3363 			(struct sockaddr_in *)&np->np_sockaddr;
3364 
3365 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3366 			ret = true;
3367 	}
3368 
3369 	return ret;
3370 }
3371 
3372 #define SENDTARGETS_BUF_LIMIT 32768U
3373 
3374 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3375 {
3376 	char *payload = NULL;
3377 	struct iscsi_conn *conn = cmd->conn;
3378 	struct iscsi_portal_group *tpg;
3379 	struct iscsi_tiqn *tiqn;
3380 	struct iscsi_tpg_np *tpg_np;
3381 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3382 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3383 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3384 
3385 	buffer_len = max(conn->conn_ops->MaxRecvDataSegmentLength,
3386 			 SENDTARGETS_BUF_LIMIT);
3387 
3388 	payload = kzalloc(buffer_len, GFP_KERNEL);
3389 	if (!payload) {
3390 		pr_err("Unable to allocate memory for sendtargets"
3391 				" response.\n");
3392 		return -ENOMEM;
3393 	}
3394 	/*
3395 	 * Locate pointer to iqn./eui. string for IFC_SENDTARGETS_SINGLE
3396 	 * explicit case..
3397 	 */
3398 	if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) {
3399 		text_ptr = strchr(text_in, '=');
3400 		if (!text_ptr) {
3401 			pr_err("Unable to locate '=' string in text_in:"
3402 			       " %s\n", text_in);
3403 			kfree(payload);
3404 			return -EINVAL;
3405 		}
3406 		/*
3407 		 * Skip over '=' character..
3408 		 */
3409 		text_ptr += 1;
3410 	}
3411 
3412 	spin_lock(&tiqn_lock);
3413 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3414 		if ((cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) &&
3415 		     strcmp(tiqn->tiqn, text_ptr)) {
3416 			continue;
3417 		}
3418 
3419 		len = sprintf(buf, "TargetName=%s", tiqn->tiqn);
3420 		len += 1;
3421 
3422 		if ((len + payload_len) > buffer_len) {
3423 			end_of_buf = 1;
3424 			goto eob;
3425 		}
3426 		memcpy(payload + payload_len, buf, len);
3427 		payload_len += len;
3428 
3429 		spin_lock(&tiqn->tiqn_tpg_lock);
3430 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3431 
3432 			spin_lock(&tpg->tpg_state_lock);
3433 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3434 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3435 				spin_unlock(&tpg->tpg_state_lock);
3436 				continue;
3437 			}
3438 			spin_unlock(&tpg->tpg_state_lock);
3439 
3440 			spin_lock(&tpg->tpg_np_lock);
3441 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3442 						tpg_np_list) {
3443 				struct iscsi_np *np = tpg_np->tpg_np;
3444 				bool inaddr_any = iscsit_check_inaddr_any(np);
3445 
3446 				len = sprintf(buf, "TargetAddress="
3447 					"%s%s%s:%hu,%hu",
3448 					(np->np_sockaddr.ss_family == AF_INET6) ?
3449 					"[" : "", (inaddr_any == false) ?
3450 						np->np_ip : conn->local_ip,
3451 					(np->np_sockaddr.ss_family == AF_INET6) ?
3452 					"]" : "", (inaddr_any == false) ?
3453 						np->np_port : conn->local_port,
3454 					tpg->tpgt);
3455 				len += 1;
3456 
3457 				if ((len + payload_len) > buffer_len) {
3458 					spin_unlock(&tpg->tpg_np_lock);
3459 					spin_unlock(&tiqn->tiqn_tpg_lock);
3460 					end_of_buf = 1;
3461 					goto eob;
3462 				}
3463 				memcpy(payload + payload_len, buf, len);
3464 				payload_len += len;
3465 			}
3466 			spin_unlock(&tpg->tpg_np_lock);
3467 		}
3468 		spin_unlock(&tiqn->tiqn_tpg_lock);
3469 eob:
3470 		if (end_of_buf)
3471 			break;
3472 
3473 		if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE)
3474 			break;
3475 	}
3476 	spin_unlock(&tiqn_lock);
3477 
3478 	cmd->buf_ptr = payload;
3479 
3480 	return payload_len;
3481 }
3482 
3483 int
3484 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3485 		      struct iscsi_text_rsp *hdr)
3486 {
3487 	int text_length, padding;
3488 
3489 	text_length = iscsit_build_sendtargets_response(cmd);
3490 	if (text_length < 0)
3491 		return text_length;
3492 
3493 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3494 	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3495 	padding = ((-text_length) & 3);
3496 	hton24(hdr->dlength, text_length);
3497 	hdr->itt = cmd->init_task_tag;
3498 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3499 	cmd->stat_sn = conn->stat_sn++;
3500 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3501 
3502 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3503 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3504 	hdr->max_cmdsn = cpu_to_be32(conn->sess->max_cmd_sn);
3505 
3506 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3507 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3508 		text_length, conn->cid);
3509 
3510 	return text_length + padding;
3511 }
3512 EXPORT_SYMBOL(iscsit_build_text_rsp);
3513 
3514 /*
3515  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3516  *	MaxRecvDataSegmentLength.
3517  */
3518 static int iscsit_send_text_rsp(
3519 	struct iscsi_cmd *cmd,
3520 	struct iscsi_conn *conn)
3521 {
3522 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3523 	struct kvec *iov;
3524 	u32 tx_size = 0;
3525 	int text_length, iov_count = 0, rc;
3526 
3527 	rc = iscsit_build_text_rsp(cmd, conn, hdr);
3528 	if (rc < 0)
3529 		return rc;
3530 
3531 	text_length = rc;
3532 	iov = &cmd->iov_misc[0];
3533 	iov[iov_count].iov_base = cmd->pdu;
3534 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3535 	iov[iov_count].iov_base	= cmd->buf_ptr;
3536 	iov[iov_count++].iov_len = text_length;
3537 
3538 	tx_size += (ISCSI_HDR_LEN + text_length);
3539 
3540 	if (conn->conn_ops->HeaderDigest) {
3541 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3542 
3543 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3544 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3545 
3546 		iov[0].iov_len += ISCSI_CRC_LEN;
3547 		tx_size += ISCSI_CRC_LEN;
3548 		pr_debug("Attaching CRC32 HeaderDigest for"
3549 			" Text Response PDU 0x%08x\n", *header_digest);
3550 	}
3551 
3552 	if (conn->conn_ops->DataDigest) {
3553 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3554 				cmd->buf_ptr, text_length,
3555 				0, NULL, (u8 *)&cmd->data_crc);
3556 
3557 		iov[iov_count].iov_base	= &cmd->data_crc;
3558 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3559 		tx_size	+= ISCSI_CRC_LEN;
3560 
3561 		pr_debug("Attaching DataDigest for %u bytes of text"
3562 			" data, CRC 0x%08x\n", text_length,
3563 			cmd->data_crc);
3564 	}
3565 
3566 	cmd->iov_misc_count = iov_count;
3567 	cmd->tx_size = tx_size;
3568 
3569 	return 0;
3570 }
3571 
3572 void
3573 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3574 		    struct iscsi_reject *hdr)
3575 {
3576 	hdr->opcode		= ISCSI_OP_REJECT;
3577 	hdr->reason		= cmd->reject_reason;
3578 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3579 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3580 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3581 	cmd->stat_sn		= conn->stat_sn++;
3582 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3583 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3584 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3585 
3586 }
3587 EXPORT_SYMBOL(iscsit_build_reject);
3588 
3589 static int iscsit_send_reject(
3590 	struct iscsi_cmd *cmd,
3591 	struct iscsi_conn *conn)
3592 {
3593 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3594 	struct kvec *iov;
3595 	u32 iov_count = 0, tx_size;
3596 
3597 	iscsit_build_reject(cmd, conn, hdr);
3598 
3599 	iov = &cmd->iov_misc[0];
3600 	iov[iov_count].iov_base = cmd->pdu;
3601 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3602 	iov[iov_count].iov_base = cmd->buf_ptr;
3603 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3604 
3605 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3606 
3607 	if (conn->conn_ops->HeaderDigest) {
3608 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3609 
3610 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3611 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3612 
3613 		iov[0].iov_len += ISCSI_CRC_LEN;
3614 		tx_size += ISCSI_CRC_LEN;
3615 		pr_debug("Attaching CRC32 HeaderDigest for"
3616 			" REJECT PDU 0x%08x\n", *header_digest);
3617 	}
3618 
3619 	if (conn->conn_ops->DataDigest) {
3620 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->buf_ptr,
3621 				ISCSI_HDR_LEN, 0, NULL, (u8 *)&cmd->data_crc);
3622 
3623 		iov[iov_count].iov_base = &cmd->data_crc;
3624 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3625 		tx_size += ISCSI_CRC_LEN;
3626 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3627 				" PDU 0x%08x\n", cmd->data_crc);
3628 	}
3629 
3630 	cmd->iov_misc_count = iov_count;
3631 	cmd->tx_size = tx_size;
3632 
3633 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3634 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3635 
3636 	return 0;
3637 }
3638 
3639 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3640 {
3641 	struct iscsi_thread_set *ts = conn->thread_set;
3642 	int ord, cpu;
3643 	/*
3644 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3645 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3646 	 *
3647 	 * Here we use thread_id to determine which CPU that this
3648 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3649 	 * execute upon.
3650 	 */
3651 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3652 	for_each_online_cpu(cpu) {
3653 		if (ord-- == 0) {
3654 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3655 			return;
3656 		}
3657 	}
3658 	/*
3659 	 * This should never be reached..
3660 	 */
3661 	dump_stack();
3662 	cpumask_setall(conn->conn_cpumask);
3663 }
3664 
3665 static inline void iscsit_thread_check_cpumask(
3666 	struct iscsi_conn *conn,
3667 	struct task_struct *p,
3668 	int mode)
3669 {
3670 	char buf[128];
3671 	/*
3672 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3673 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3674 	 */
3675 	if (mode == 1) {
3676 		if (!conn->conn_tx_reset_cpumask)
3677 			return;
3678 		conn->conn_tx_reset_cpumask = 0;
3679 	} else {
3680 		if (!conn->conn_rx_reset_cpumask)
3681 			return;
3682 		conn->conn_rx_reset_cpumask = 0;
3683 	}
3684 	/*
3685 	 * Update the CPU mask for this single kthread so that
3686 	 * both TX and RX kthreads are scheduled to run on the
3687 	 * same CPU.
3688 	 */
3689 	memset(buf, 0, 128);
3690 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3691 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3692 }
3693 
3694 static int
3695 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3696 {
3697 	int ret;
3698 
3699 	switch (state) {
3700 	case ISTATE_SEND_R2T:
3701 		ret = iscsit_send_r2t(cmd, conn);
3702 		if (ret < 0)
3703 			goto err;
3704 		break;
3705 	case ISTATE_REMOVE:
3706 		spin_lock_bh(&conn->cmd_lock);
3707 		list_del(&cmd->i_conn_node);
3708 		spin_unlock_bh(&conn->cmd_lock);
3709 
3710 		iscsit_free_cmd(cmd, false);
3711 		break;
3712 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3713 		iscsit_mod_nopin_response_timer(conn);
3714 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3715 		if (ret < 0)
3716 			goto err;
3717 		break;
3718 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3719 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3720 		if (ret < 0)
3721 			goto err;
3722 		break;
3723 	default:
3724 		pr_err("Unknown Opcode: 0x%02x ITT:"
3725 		       " 0x%08x, i_state: %d on CID: %hu\n",
3726 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3727 		       conn->cid);
3728 		goto err;
3729 	}
3730 
3731 	return 0;
3732 
3733 err:
3734 	return -1;
3735 }
3736 
3737 static int
3738 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3739 {
3740 	struct iscsit_transport *t = conn->conn_transport;
3741 	struct iscsi_queue_req *qr;
3742 	struct iscsi_cmd *cmd;
3743 	u8 state;
3744 	int ret;
3745 
3746 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3747 		atomic_set(&conn->check_immediate_queue, 0);
3748 		cmd = qr->cmd;
3749 		state = qr->state;
3750 		kmem_cache_free(lio_qr_cache, qr);
3751 
3752 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3753 		if (ret < 0)
3754 			return ret;
3755 	}
3756 
3757 	return 0;
3758 }
3759 
3760 static int
3761 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3762 {
3763 	int ret;
3764 
3765 check_rsp_state:
3766 	switch (state) {
3767 	case ISTATE_SEND_DATAIN:
3768 		ret = iscsit_send_datain(cmd, conn);
3769 		if (ret < 0)
3770 			goto err;
3771 		else if (!ret)
3772 			/* more drs */
3773 			goto check_rsp_state;
3774 		else if (ret == 1) {
3775 			/* all done */
3776 			spin_lock_bh(&cmd->istate_lock);
3777 			cmd->i_state = ISTATE_SENT_STATUS;
3778 			spin_unlock_bh(&cmd->istate_lock);
3779 
3780 			if (atomic_read(&conn->check_immediate_queue))
3781 				return 1;
3782 
3783 			return 0;
3784 		} else if (ret == 2) {
3785 			/* Still must send status,
3786 			   SCF_TRANSPORT_TASK_SENSE was set */
3787 			spin_lock_bh(&cmd->istate_lock);
3788 			cmd->i_state = ISTATE_SEND_STATUS;
3789 			spin_unlock_bh(&cmd->istate_lock);
3790 			state = ISTATE_SEND_STATUS;
3791 			goto check_rsp_state;
3792 		}
3793 
3794 		break;
3795 	case ISTATE_SEND_STATUS:
3796 	case ISTATE_SEND_STATUS_RECOVERY:
3797 		ret = iscsit_send_response(cmd, conn);
3798 		break;
3799 	case ISTATE_SEND_LOGOUTRSP:
3800 		ret = iscsit_send_logout(cmd, conn);
3801 		break;
3802 	case ISTATE_SEND_ASYNCMSG:
3803 		ret = iscsit_send_conn_drop_async_message(
3804 			cmd, conn);
3805 		break;
3806 	case ISTATE_SEND_NOPIN:
3807 		ret = iscsit_send_nopin(cmd, conn);
3808 		break;
3809 	case ISTATE_SEND_REJECT:
3810 		ret = iscsit_send_reject(cmd, conn);
3811 		break;
3812 	case ISTATE_SEND_TASKMGTRSP:
3813 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3814 		if (ret != 0)
3815 			break;
3816 		ret = iscsit_tmr_post_handler(cmd, conn);
3817 		if (ret != 0)
3818 			iscsit_fall_back_to_erl0(conn->sess);
3819 		break;
3820 	case ISTATE_SEND_TEXTRSP:
3821 		ret = iscsit_send_text_rsp(cmd, conn);
3822 		break;
3823 	default:
3824 		pr_err("Unknown Opcode: 0x%02x ITT:"
3825 		       " 0x%08x, i_state: %d on CID: %hu\n",
3826 		       cmd->iscsi_opcode, cmd->init_task_tag,
3827 		       state, conn->cid);
3828 		goto err;
3829 	}
3830 	if (ret < 0)
3831 		goto err;
3832 
3833 	if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3834 		iscsit_tx_thread_wait_for_tcp(conn);
3835 		iscsit_unmap_iovec(cmd);
3836 		goto err;
3837 	}
3838 	iscsit_unmap_iovec(cmd);
3839 
3840 	switch (state) {
3841 	case ISTATE_SEND_LOGOUTRSP:
3842 		if (!iscsit_logout_post_handler(cmd, conn))
3843 			goto restart;
3844 		/* fall through */
3845 	case ISTATE_SEND_STATUS:
3846 	case ISTATE_SEND_ASYNCMSG:
3847 	case ISTATE_SEND_NOPIN:
3848 	case ISTATE_SEND_STATUS_RECOVERY:
3849 	case ISTATE_SEND_TEXTRSP:
3850 	case ISTATE_SEND_TASKMGTRSP:
3851 	case ISTATE_SEND_REJECT:
3852 		spin_lock_bh(&cmd->istate_lock);
3853 		cmd->i_state = ISTATE_SENT_STATUS;
3854 		spin_unlock_bh(&cmd->istate_lock);
3855 		break;
3856 	default:
3857 		pr_err("Unknown Opcode: 0x%02x ITT:"
3858 		       " 0x%08x, i_state: %d on CID: %hu\n",
3859 		       cmd->iscsi_opcode, cmd->init_task_tag,
3860 		       cmd->i_state, conn->cid);
3861 		goto err;
3862 	}
3863 
3864 	if (atomic_read(&conn->check_immediate_queue))
3865 		return 1;
3866 
3867 	return 0;
3868 
3869 err:
3870 	return -1;
3871 restart:
3872 	return -EAGAIN;
3873 }
3874 
3875 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3876 {
3877 	struct iscsit_transport *t = conn->conn_transport;
3878 	struct iscsi_queue_req *qr;
3879 	struct iscsi_cmd *cmd;
3880 	u8 state;
3881 	int ret;
3882 
3883 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3884 		cmd = qr->cmd;
3885 		state = qr->state;
3886 		kmem_cache_free(lio_qr_cache, qr);
3887 
3888 		ret = t->iscsit_response_queue(conn, cmd, state);
3889 		if (ret == 1 || ret < 0)
3890 			return ret;
3891 	}
3892 
3893 	return 0;
3894 }
3895 
3896 int iscsi_target_tx_thread(void *arg)
3897 {
3898 	int ret = 0;
3899 	struct iscsi_conn *conn;
3900 	struct iscsi_thread_set *ts = arg;
3901 	/*
3902 	 * Allow ourselves to be interrupted by SIGINT so that a
3903 	 * connection recovery / failure event can be triggered externally.
3904 	 */
3905 	allow_signal(SIGINT);
3906 
3907 restart:
3908 	conn = iscsi_tx_thread_pre_handler(ts);
3909 	if (!conn)
3910 		goto out;
3911 
3912 	ret = 0;
3913 
3914 	while (!kthread_should_stop()) {
3915 		/*
3916 		 * Ensure that both TX and RX per connection kthreads
3917 		 * are scheduled to run on the same CPU.
3918 		 */
3919 		iscsit_thread_check_cpumask(conn, current, 1);
3920 
3921 		wait_event_interruptible(conn->queues_wq,
3922 					 !iscsit_conn_all_queues_empty(conn) ||
3923 					 ts->status == ISCSI_THREAD_SET_RESET);
3924 
3925 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3926 		     signal_pending(current))
3927 			goto transport_err;
3928 
3929 get_immediate:
3930 		ret = iscsit_handle_immediate_queue(conn);
3931 		if (ret < 0)
3932 			goto transport_err;
3933 
3934 		ret = iscsit_handle_response_queue(conn);
3935 		if (ret == 1)
3936 			goto get_immediate;
3937 		else if (ret == -EAGAIN)
3938 			goto restart;
3939 		else if (ret < 0)
3940 			goto transport_err;
3941 	}
3942 
3943 transport_err:
3944 	iscsit_take_action_for_connection_exit(conn);
3945 	goto restart;
3946 out:
3947 	return 0;
3948 }
3949 
3950 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3951 {
3952 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3953 	struct iscsi_cmd *cmd;
3954 	int ret = 0;
3955 
3956 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3957 	case ISCSI_OP_SCSI_CMD:
3958 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3959 		if (!cmd)
3960 			goto reject;
3961 
3962 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3963 		break;
3964 	case ISCSI_OP_SCSI_DATA_OUT:
3965 		ret = iscsit_handle_data_out(conn, buf);
3966 		break;
3967 	case ISCSI_OP_NOOP_OUT:
3968 		cmd = NULL;
3969 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3970 			cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3971 			if (!cmd)
3972 				goto reject;
3973 		}
3974 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3975 		break;
3976 	case ISCSI_OP_SCSI_TMFUNC:
3977 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3978 		if (!cmd)
3979 			goto reject;
3980 
3981 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3982 		break;
3983 	case ISCSI_OP_TEXT:
3984 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3985 		if (!cmd)
3986 			goto reject;
3987 
3988 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3989 		break;
3990 	case ISCSI_OP_LOGOUT:
3991 		cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
3992 		if (!cmd)
3993 			goto reject;
3994 
3995 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3996 		if (ret > 0)
3997 			wait_for_completion_timeout(&conn->conn_logout_comp,
3998 					SECONDS_FOR_LOGOUT_COMP * HZ);
3999 		break;
4000 	case ISCSI_OP_SNACK:
4001 		ret = iscsit_handle_snack(conn, buf);
4002 		break;
4003 	default:
4004 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
4005 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
4006 			pr_err("Cannot recover from unknown"
4007 			" opcode while ERL=0, closing iSCSI connection.\n");
4008 			return -1;
4009 		}
4010 		if (!conn->conn_ops->OFMarker) {
4011 			pr_err("Unable to recover from unknown"
4012 			" opcode while OFMarker=No, closing iSCSI"
4013 				" connection.\n");
4014 			return -1;
4015 		}
4016 		if (iscsit_recover_from_unknown_opcode(conn) < 0) {
4017 			pr_err("Unable to recover from unknown"
4018 				" opcode, closing iSCSI connection.\n");
4019 			return -1;
4020 		}
4021 		break;
4022 	}
4023 
4024 	return ret;
4025 reject:
4026 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4027 }
4028 
4029 int iscsi_target_rx_thread(void *arg)
4030 {
4031 	int ret;
4032 	u8 buffer[ISCSI_HDR_LEN], opcode;
4033 	u32 checksum = 0, digest = 0;
4034 	struct iscsi_conn *conn = NULL;
4035 	struct iscsi_thread_set *ts = arg;
4036 	struct kvec iov;
4037 	/*
4038 	 * Allow ourselves to be interrupted by SIGINT so that a
4039 	 * connection recovery / failure event can be triggered externally.
4040 	 */
4041 	allow_signal(SIGINT);
4042 
4043 restart:
4044 	conn = iscsi_rx_thread_pre_handler(ts);
4045 	if (!conn)
4046 		goto out;
4047 
4048 	if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
4049 		struct completion comp;
4050 		int rc;
4051 
4052 		init_completion(&comp);
4053 		rc = wait_for_completion_interruptible(&comp);
4054 		if (rc < 0)
4055 			goto transport_err;
4056 
4057 		goto out;
4058 	}
4059 
4060 	while (!kthread_should_stop()) {
4061 		/*
4062 		 * Ensure that both TX and RX per connection kthreads
4063 		 * are scheduled to run on the same CPU.
4064 		 */
4065 		iscsit_thread_check_cpumask(conn, current, 0);
4066 
4067 		memset(buffer, 0, ISCSI_HDR_LEN);
4068 		memset(&iov, 0, sizeof(struct kvec));
4069 
4070 		iov.iov_base	= buffer;
4071 		iov.iov_len	= ISCSI_HDR_LEN;
4072 
4073 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4074 		if (ret != ISCSI_HDR_LEN) {
4075 			iscsit_rx_thread_wait_for_tcp(conn);
4076 			goto transport_err;
4077 		}
4078 
4079 		if (conn->conn_ops->HeaderDigest) {
4080 			iov.iov_base	= &digest;
4081 			iov.iov_len	= ISCSI_CRC_LEN;
4082 
4083 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4084 			if (ret != ISCSI_CRC_LEN) {
4085 				iscsit_rx_thread_wait_for_tcp(conn);
4086 				goto transport_err;
4087 			}
4088 
4089 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
4090 					buffer, ISCSI_HDR_LEN,
4091 					0, NULL, (u8 *)&checksum);
4092 
4093 			if (digest != checksum) {
4094 				pr_err("HeaderDigest CRC32C failed,"
4095 					" received 0x%08x, computed 0x%08x\n",
4096 					digest, checksum);
4097 				/*
4098 				 * Set the PDU to 0xff so it will intentionally
4099 				 * hit default in the switch below.
4100 				 */
4101 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4102 				spin_lock_bh(&conn->sess->session_stats_lock);
4103 				conn->sess->conn_digest_errors++;
4104 				spin_unlock_bh(&conn->sess->session_stats_lock);
4105 			} else {
4106 				pr_debug("Got HeaderDigest CRC32C"
4107 						" 0x%08x\n", checksum);
4108 			}
4109 		}
4110 
4111 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4112 			goto transport_err;
4113 
4114 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4115 
4116 		if (conn->sess->sess_ops->SessionType &&
4117 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4118 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4119 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4120 			" while in Discovery Session, rejecting.\n", opcode);
4121 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4122 					  buffer);
4123 			goto transport_err;
4124 		}
4125 
4126 		ret = iscsi_target_rx_opcode(conn, buffer);
4127 		if (ret < 0)
4128 			goto transport_err;
4129 	}
4130 
4131 transport_err:
4132 	if (!signal_pending(current))
4133 		atomic_set(&conn->transport_failed, 1);
4134 	iscsit_take_action_for_connection_exit(conn);
4135 	goto restart;
4136 out:
4137 	return 0;
4138 }
4139 
4140 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4141 {
4142 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4143 	struct iscsi_session *sess = conn->sess;
4144 	/*
4145 	 * We expect this function to only ever be called from either RX or TX
4146 	 * thread context via iscsit_close_connection() once the other context
4147 	 * has been reset -> returned sleeping pre-handler state.
4148 	 */
4149 	spin_lock_bh(&conn->cmd_lock);
4150 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
4151 
4152 		list_del(&cmd->i_conn_node);
4153 		spin_unlock_bh(&conn->cmd_lock);
4154 
4155 		iscsit_increment_maxcmdsn(cmd, sess);
4156 
4157 		iscsit_free_cmd(cmd, true);
4158 
4159 		spin_lock_bh(&conn->cmd_lock);
4160 	}
4161 	spin_unlock_bh(&conn->cmd_lock);
4162 }
4163 
4164 static void iscsit_stop_timers_for_cmds(
4165 	struct iscsi_conn *conn)
4166 {
4167 	struct iscsi_cmd *cmd;
4168 
4169 	spin_lock_bh(&conn->cmd_lock);
4170 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4171 		if (cmd->data_direction == DMA_TO_DEVICE)
4172 			iscsit_stop_dataout_timer(cmd);
4173 	}
4174 	spin_unlock_bh(&conn->cmd_lock);
4175 }
4176 
4177 int iscsit_close_connection(
4178 	struct iscsi_conn *conn)
4179 {
4180 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4181 	struct iscsi_session	*sess = conn->sess;
4182 
4183 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4184 		" %u\n", conn->cid, sess->sid);
4185 	/*
4186 	 * Always up conn_logout_comp just in case the RX Thread is sleeping
4187 	 * and the logout response never got sent because the connection
4188 	 * failed.
4189 	 */
4190 	complete(&conn->conn_logout_comp);
4191 
4192 	iscsi_release_thread_set(conn);
4193 
4194 	iscsit_stop_timers_for_cmds(conn);
4195 	iscsit_stop_nopin_response_timer(conn);
4196 	iscsit_stop_nopin_timer(conn);
4197 	iscsit_free_queue_reqs_for_conn(conn);
4198 
4199 	/*
4200 	 * During Connection recovery drop unacknowledged out of order
4201 	 * commands for this connection, and prepare the other commands
4202 	 * for realligence.
4203 	 *
4204 	 * During normal operation clear the out of order commands (but
4205 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4206 	 * struct iscsi_cmds.
4207 	 */
4208 	if (atomic_read(&conn->connection_recovery)) {
4209 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4210 		iscsit_prepare_cmds_for_realligance(conn);
4211 	} else {
4212 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4213 		iscsit_release_commands_from_conn(conn);
4214 	}
4215 
4216 	/*
4217 	 * Handle decrementing session or connection usage count if
4218 	 * a logout response was not able to be sent because the
4219 	 * connection failed.  Fall back to Session Recovery here.
4220 	 */
4221 	if (atomic_read(&conn->conn_logout_remove)) {
4222 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4223 			iscsit_dec_conn_usage_count(conn);
4224 			iscsit_dec_session_usage_count(sess);
4225 		}
4226 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4227 			iscsit_dec_conn_usage_count(conn);
4228 
4229 		atomic_set(&conn->conn_logout_remove, 0);
4230 		atomic_set(&sess->session_reinstatement, 0);
4231 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4232 	}
4233 
4234 	spin_lock_bh(&sess->conn_lock);
4235 	list_del(&conn->conn_list);
4236 
4237 	/*
4238 	 * Attempt to let the Initiator know this connection failed by
4239 	 * sending an Connection Dropped Async Message on another
4240 	 * active connection.
4241 	 */
4242 	if (atomic_read(&conn->connection_recovery))
4243 		iscsit_build_conn_drop_async_message(conn);
4244 
4245 	spin_unlock_bh(&sess->conn_lock);
4246 
4247 	/*
4248 	 * If connection reinstatement is being performed on this connection,
4249 	 * up the connection reinstatement semaphore that is being blocked on
4250 	 * in iscsit_cause_connection_reinstatement().
4251 	 */
4252 	spin_lock_bh(&conn->state_lock);
4253 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4254 		spin_unlock_bh(&conn->state_lock);
4255 		complete(&conn->conn_wait_comp);
4256 		wait_for_completion(&conn->conn_post_wait_comp);
4257 		spin_lock_bh(&conn->state_lock);
4258 	}
4259 
4260 	/*
4261 	 * If connection reinstatement is being performed on this connection
4262 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4263 	 * connection wait rcfr semaphore that is being blocked on
4264 	 * an iscsit_connection_reinstatement_rcfr().
4265 	 */
4266 	if (atomic_read(&conn->connection_wait_rcfr)) {
4267 		spin_unlock_bh(&conn->state_lock);
4268 		complete(&conn->conn_wait_rcfr_comp);
4269 		wait_for_completion(&conn->conn_post_wait_comp);
4270 		spin_lock_bh(&conn->state_lock);
4271 	}
4272 	atomic_set(&conn->connection_reinstatement, 1);
4273 	spin_unlock_bh(&conn->state_lock);
4274 
4275 	/*
4276 	 * If any other processes are accessing this connection pointer we
4277 	 * must wait until they have completed.
4278 	 */
4279 	iscsit_check_conn_usage_count(conn);
4280 
4281 	if (conn->conn_rx_hash.tfm)
4282 		crypto_free_hash(conn->conn_rx_hash.tfm);
4283 	if (conn->conn_tx_hash.tfm)
4284 		crypto_free_hash(conn->conn_tx_hash.tfm);
4285 
4286 	if (conn->conn_cpumask)
4287 		free_cpumask_var(conn->conn_cpumask);
4288 
4289 	kfree(conn->conn_ops);
4290 	conn->conn_ops = NULL;
4291 
4292 	if (conn->sock)
4293 		sock_release(conn->sock);
4294 
4295 	if (conn->conn_transport->iscsit_free_conn)
4296 		conn->conn_transport->iscsit_free_conn(conn);
4297 
4298 	iscsit_put_transport(conn->conn_transport);
4299 
4300 	conn->thread_set = NULL;
4301 
4302 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4303 	conn->conn_state = TARG_CONN_STATE_FREE;
4304 	kfree(conn);
4305 
4306 	spin_lock_bh(&sess->conn_lock);
4307 	atomic_dec(&sess->nconn);
4308 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4309 		" %s\n", atomic_read(&sess->nconn),
4310 		sess->sess_ops->InitiatorName);
4311 	/*
4312 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4313 	 * Session that they all fail.
4314 	 */
4315 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4316 	     !atomic_read(&sess->session_logout))
4317 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4318 
4319 	/*
4320 	 * If this was not the last connection in the session, and we are
4321 	 * performing session reinstatement or falling back to ERL=0, call
4322 	 * iscsit_stop_session() without sleeping to shutdown the other
4323 	 * active connections.
4324 	 */
4325 	if (atomic_read(&sess->nconn)) {
4326 		if (!atomic_read(&sess->session_reinstatement) &&
4327 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4328 			spin_unlock_bh(&sess->conn_lock);
4329 			return 0;
4330 		}
4331 		if (!atomic_read(&sess->session_stop_active)) {
4332 			atomic_set(&sess->session_stop_active, 1);
4333 			spin_unlock_bh(&sess->conn_lock);
4334 			iscsit_stop_session(sess, 0, 0);
4335 			return 0;
4336 		}
4337 		spin_unlock_bh(&sess->conn_lock);
4338 		return 0;
4339 	}
4340 
4341 	/*
4342 	 * If this was the last connection in the session and one of the
4343 	 * following is occurring:
4344 	 *
4345 	 * Session Reinstatement is not being performed, and are falling back
4346 	 * to ERL=0 call iscsit_close_session().
4347 	 *
4348 	 * Session Logout was requested.  iscsit_close_session() will be called
4349 	 * elsewhere.
4350 	 *
4351 	 * Session Continuation is not being performed, start the Time2Retain
4352 	 * handler and check if sleep_on_sess_wait_sem is active.
4353 	 */
4354 	if (!atomic_read(&sess->session_reinstatement) &&
4355 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4356 		spin_unlock_bh(&sess->conn_lock);
4357 		target_put_session(sess->se_sess);
4358 
4359 		return 0;
4360 	} else if (atomic_read(&sess->session_logout)) {
4361 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4362 		sess->session_state = TARG_SESS_STATE_FREE;
4363 		spin_unlock_bh(&sess->conn_lock);
4364 
4365 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4366 			complete(&sess->session_wait_comp);
4367 
4368 		return 0;
4369 	} else {
4370 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4371 		sess->session_state = TARG_SESS_STATE_FAILED;
4372 
4373 		if (!atomic_read(&sess->session_continuation)) {
4374 			spin_unlock_bh(&sess->conn_lock);
4375 			iscsit_start_time2retain_handler(sess);
4376 		} else
4377 			spin_unlock_bh(&sess->conn_lock);
4378 
4379 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4380 			complete(&sess->session_wait_comp);
4381 
4382 		return 0;
4383 	}
4384 	spin_unlock_bh(&sess->conn_lock);
4385 
4386 	return 0;
4387 }
4388 
4389 int iscsit_close_session(struct iscsi_session *sess)
4390 {
4391 	struct iscsi_portal_group *tpg = ISCSI_TPG_S(sess);
4392 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4393 
4394 	if (atomic_read(&sess->nconn)) {
4395 		pr_err("%d connection(s) still exist for iSCSI session"
4396 			" to %s\n", atomic_read(&sess->nconn),
4397 			sess->sess_ops->InitiatorName);
4398 		BUG();
4399 	}
4400 
4401 	spin_lock_bh(&se_tpg->session_lock);
4402 	atomic_set(&sess->session_logout, 1);
4403 	atomic_set(&sess->session_reinstatement, 1);
4404 	iscsit_stop_time2retain_timer(sess);
4405 	spin_unlock_bh(&se_tpg->session_lock);
4406 
4407 	/*
4408 	 * transport_deregister_session_configfs() will clear the
4409 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4410 	 * can be setting it again with __transport_register_session() in
4411 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4412 	 * completes in iscsi_np context.
4413 	 */
4414 	transport_deregister_session_configfs(sess->se_sess);
4415 
4416 	/*
4417 	 * If any other processes are accessing this session pointer we must
4418 	 * wait until they have completed.  If we are in an interrupt (the
4419 	 * time2retain handler) and contain and active session usage count we
4420 	 * restart the timer and exit.
4421 	 */
4422 	if (!in_interrupt()) {
4423 		if (iscsit_check_session_usage_count(sess) == 1)
4424 			iscsit_stop_session(sess, 1, 1);
4425 	} else {
4426 		if (iscsit_check_session_usage_count(sess) == 2) {
4427 			atomic_set(&sess->session_logout, 0);
4428 			iscsit_start_time2retain_handler(sess);
4429 			return 0;
4430 		}
4431 	}
4432 
4433 	transport_deregister_session(sess->se_sess);
4434 
4435 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4436 		iscsit_free_connection_recovery_entires(sess);
4437 
4438 	iscsit_free_all_ooo_cmdsns(sess);
4439 
4440 	spin_lock_bh(&se_tpg->session_lock);
4441 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4442 	sess->session_state = TARG_SESS_STATE_FREE;
4443 	pr_debug("Released iSCSI session from node: %s\n",
4444 			sess->sess_ops->InitiatorName);
4445 	tpg->nsessions--;
4446 	if (tpg->tpg_tiqn)
4447 		tpg->tpg_tiqn->tiqn_nsessions--;
4448 
4449 	pr_debug("Decremented number of active iSCSI Sessions on"
4450 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4451 
4452 	spin_lock(&sess_idr_lock);
4453 	idr_remove(&sess_idr, sess->session_index);
4454 	spin_unlock(&sess_idr_lock);
4455 
4456 	kfree(sess->sess_ops);
4457 	sess->sess_ops = NULL;
4458 	spin_unlock_bh(&se_tpg->session_lock);
4459 
4460 	kfree(sess);
4461 	return 0;
4462 }
4463 
4464 static void iscsit_logout_post_handler_closesession(
4465 	struct iscsi_conn *conn)
4466 {
4467 	struct iscsi_session *sess = conn->sess;
4468 
4469 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4470 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4471 
4472 	atomic_set(&conn->conn_logout_remove, 0);
4473 	complete(&conn->conn_logout_comp);
4474 
4475 	iscsit_dec_conn_usage_count(conn);
4476 	iscsit_stop_session(sess, 1, 1);
4477 	iscsit_dec_session_usage_count(sess);
4478 	target_put_session(sess->se_sess);
4479 }
4480 
4481 static void iscsit_logout_post_handler_samecid(
4482 	struct iscsi_conn *conn)
4483 {
4484 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4485 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4486 
4487 	atomic_set(&conn->conn_logout_remove, 0);
4488 	complete(&conn->conn_logout_comp);
4489 
4490 	iscsit_cause_connection_reinstatement(conn, 1);
4491 	iscsit_dec_conn_usage_count(conn);
4492 }
4493 
4494 static void iscsit_logout_post_handler_diffcid(
4495 	struct iscsi_conn *conn,
4496 	u16 cid)
4497 {
4498 	struct iscsi_conn *l_conn;
4499 	struct iscsi_session *sess = conn->sess;
4500 
4501 	if (!sess)
4502 		return;
4503 
4504 	spin_lock_bh(&sess->conn_lock);
4505 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4506 		if (l_conn->cid == cid) {
4507 			iscsit_inc_conn_usage_count(l_conn);
4508 			break;
4509 		}
4510 	}
4511 	spin_unlock_bh(&sess->conn_lock);
4512 
4513 	if (!l_conn)
4514 		return;
4515 
4516 	if (l_conn->sock)
4517 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4518 
4519 	spin_lock_bh(&l_conn->state_lock);
4520 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4521 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4522 	spin_unlock_bh(&l_conn->state_lock);
4523 
4524 	iscsit_cause_connection_reinstatement(l_conn, 1);
4525 	iscsit_dec_conn_usage_count(l_conn);
4526 }
4527 
4528 /*
4529  *	Return of 0 causes the TX thread to restart.
4530  */
4531 int iscsit_logout_post_handler(
4532 	struct iscsi_cmd *cmd,
4533 	struct iscsi_conn *conn)
4534 {
4535 	int ret = 0;
4536 
4537 	switch (cmd->logout_reason) {
4538 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4539 		switch (cmd->logout_response) {
4540 		case ISCSI_LOGOUT_SUCCESS:
4541 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4542 		default:
4543 			iscsit_logout_post_handler_closesession(conn);
4544 			break;
4545 		}
4546 		ret = 0;
4547 		break;
4548 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4549 		if (conn->cid == cmd->logout_cid) {
4550 			switch (cmd->logout_response) {
4551 			case ISCSI_LOGOUT_SUCCESS:
4552 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4553 			default:
4554 				iscsit_logout_post_handler_samecid(conn);
4555 				break;
4556 			}
4557 			ret = 0;
4558 		} else {
4559 			switch (cmd->logout_response) {
4560 			case ISCSI_LOGOUT_SUCCESS:
4561 				iscsit_logout_post_handler_diffcid(conn,
4562 					cmd->logout_cid);
4563 				break;
4564 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4565 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4566 			default:
4567 				break;
4568 			}
4569 			ret = 1;
4570 		}
4571 		break;
4572 	case ISCSI_LOGOUT_REASON_RECOVERY:
4573 		switch (cmd->logout_response) {
4574 		case ISCSI_LOGOUT_SUCCESS:
4575 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4576 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4577 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4578 		default:
4579 			break;
4580 		}
4581 		ret = 1;
4582 		break;
4583 	default:
4584 		break;
4585 
4586 	}
4587 	return ret;
4588 }
4589 EXPORT_SYMBOL(iscsit_logout_post_handler);
4590 
4591 void iscsit_fail_session(struct iscsi_session *sess)
4592 {
4593 	struct iscsi_conn *conn;
4594 
4595 	spin_lock_bh(&sess->conn_lock);
4596 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4597 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4598 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4599 	}
4600 	spin_unlock_bh(&sess->conn_lock);
4601 
4602 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4603 	sess->session_state = TARG_SESS_STATE_FAILED;
4604 }
4605 
4606 int iscsit_free_session(struct iscsi_session *sess)
4607 {
4608 	u16 conn_count = atomic_read(&sess->nconn);
4609 	struct iscsi_conn *conn, *conn_tmp = NULL;
4610 	int is_last;
4611 
4612 	spin_lock_bh(&sess->conn_lock);
4613 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4614 
4615 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4616 			conn_list) {
4617 		if (conn_count == 0)
4618 			break;
4619 
4620 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4621 			is_last = 1;
4622 		} else {
4623 			iscsit_inc_conn_usage_count(conn_tmp);
4624 			is_last = 0;
4625 		}
4626 		iscsit_inc_conn_usage_count(conn);
4627 
4628 		spin_unlock_bh(&sess->conn_lock);
4629 		iscsit_cause_connection_reinstatement(conn, 1);
4630 		spin_lock_bh(&sess->conn_lock);
4631 
4632 		iscsit_dec_conn_usage_count(conn);
4633 		if (is_last == 0)
4634 			iscsit_dec_conn_usage_count(conn_tmp);
4635 
4636 		conn_count--;
4637 	}
4638 
4639 	if (atomic_read(&sess->nconn)) {
4640 		spin_unlock_bh(&sess->conn_lock);
4641 		wait_for_completion(&sess->session_wait_comp);
4642 	} else
4643 		spin_unlock_bh(&sess->conn_lock);
4644 
4645 	target_put_session(sess->se_sess);
4646 	return 0;
4647 }
4648 
4649 void iscsit_stop_session(
4650 	struct iscsi_session *sess,
4651 	int session_sleep,
4652 	int connection_sleep)
4653 {
4654 	u16 conn_count = atomic_read(&sess->nconn);
4655 	struct iscsi_conn *conn, *conn_tmp = NULL;
4656 	int is_last;
4657 
4658 	spin_lock_bh(&sess->conn_lock);
4659 	if (session_sleep)
4660 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4661 
4662 	if (connection_sleep) {
4663 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4664 				conn_list) {
4665 			if (conn_count == 0)
4666 				break;
4667 
4668 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4669 				is_last = 1;
4670 			} else {
4671 				iscsit_inc_conn_usage_count(conn_tmp);
4672 				is_last = 0;
4673 			}
4674 			iscsit_inc_conn_usage_count(conn);
4675 
4676 			spin_unlock_bh(&sess->conn_lock);
4677 			iscsit_cause_connection_reinstatement(conn, 1);
4678 			spin_lock_bh(&sess->conn_lock);
4679 
4680 			iscsit_dec_conn_usage_count(conn);
4681 			if (is_last == 0)
4682 				iscsit_dec_conn_usage_count(conn_tmp);
4683 			conn_count--;
4684 		}
4685 	} else {
4686 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4687 			iscsit_cause_connection_reinstatement(conn, 0);
4688 	}
4689 
4690 	if (session_sleep && atomic_read(&sess->nconn)) {
4691 		spin_unlock_bh(&sess->conn_lock);
4692 		wait_for_completion(&sess->session_wait_comp);
4693 	} else
4694 		spin_unlock_bh(&sess->conn_lock);
4695 }
4696 
4697 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4698 {
4699 	struct iscsi_session *sess;
4700 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4701 	struct se_session *se_sess, *se_sess_tmp;
4702 	int session_count = 0;
4703 
4704 	spin_lock_bh(&se_tpg->session_lock);
4705 	if (tpg->nsessions && !force) {
4706 		spin_unlock_bh(&se_tpg->session_lock);
4707 		return -1;
4708 	}
4709 
4710 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4711 			sess_list) {
4712 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4713 
4714 		spin_lock(&sess->conn_lock);
4715 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4716 		    atomic_read(&sess->session_logout) ||
4717 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4718 			spin_unlock(&sess->conn_lock);
4719 			continue;
4720 		}
4721 		atomic_set(&sess->session_reinstatement, 1);
4722 		spin_unlock(&sess->conn_lock);
4723 		spin_unlock_bh(&se_tpg->session_lock);
4724 
4725 		iscsit_free_session(sess);
4726 		spin_lock_bh(&se_tpg->session_lock);
4727 
4728 		session_count++;
4729 	}
4730 	spin_unlock_bh(&se_tpg->session_lock);
4731 
4732 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4733 			" Group: %hu\n", session_count, tpg->tpgt);
4734 	return 0;
4735 }
4736 
4737 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4738 MODULE_VERSION("4.1.x");
4739 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4740 MODULE_LICENSE("GPL");
4741 
4742 module_init(iscsi_target_init_module);
4743 module_exit(iscsi_target_cleanup_module);
4744