xref: /linux/drivers/target/iscsi/iscsi_target.c (revision 110e6f26af80dfd90b6e5c645b1aed7228aa580d)
1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18 
19 #include <crypto/hash.h>
20 #include <linux/string.h>
21 #include <linux/kthread.h>
22 #include <linux/completion.h>
23 #include <linux/module.h>
24 #include <linux/vmalloc.h>
25 #include <linux/idr.h>
26 #include <asm/unaligned.h>
27 #include <scsi/scsi_proto.h>
28 #include <scsi/iscsi_proto.h>
29 #include <scsi/scsi_tcq.h>
30 #include <target/target_core_base.h>
31 #include <target/target_core_fabric.h>
32 
33 #include <target/iscsi/iscsi_target_core.h>
34 #include "iscsi_target_parameters.h"
35 #include "iscsi_target_seq_pdu_list.h"
36 #include "iscsi_target_datain_values.h"
37 #include "iscsi_target_erl0.h"
38 #include "iscsi_target_erl1.h"
39 #include "iscsi_target_erl2.h"
40 #include "iscsi_target_login.h"
41 #include "iscsi_target_tmr.h"
42 #include "iscsi_target_tpg.h"
43 #include "iscsi_target_util.h"
44 #include "iscsi_target.h"
45 #include "iscsi_target_device.h"
46 #include <target/iscsi/iscsi_target_stat.h>
47 
48 #include <target/iscsi/iscsi_transport.h>
49 
50 static LIST_HEAD(g_tiqn_list);
51 static LIST_HEAD(g_np_list);
52 static DEFINE_SPINLOCK(tiqn_lock);
53 static DEFINE_MUTEX(np_lock);
54 
55 static struct idr tiqn_idr;
56 struct idr sess_idr;
57 struct mutex auth_id_lock;
58 spinlock_t sess_idr_lock;
59 
60 struct iscsit_global *iscsit_global;
61 
62 struct kmem_cache *lio_qr_cache;
63 struct kmem_cache *lio_dr_cache;
64 struct kmem_cache *lio_ooo_cache;
65 struct kmem_cache *lio_r2t_cache;
66 
67 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
68 			struct iscsi_scsi_req *, u32);
69 
70 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
71 {
72 	struct iscsi_tiqn *tiqn = NULL;
73 
74 	spin_lock(&tiqn_lock);
75 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
76 		if (!strcmp(tiqn->tiqn, buf)) {
77 
78 			spin_lock(&tiqn->tiqn_state_lock);
79 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
80 				tiqn->tiqn_access_count++;
81 				spin_unlock(&tiqn->tiqn_state_lock);
82 				spin_unlock(&tiqn_lock);
83 				return tiqn;
84 			}
85 			spin_unlock(&tiqn->tiqn_state_lock);
86 		}
87 	}
88 	spin_unlock(&tiqn_lock);
89 
90 	return NULL;
91 }
92 
93 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
94 {
95 	spin_lock(&tiqn->tiqn_state_lock);
96 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
97 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
98 		spin_unlock(&tiqn->tiqn_state_lock);
99 		return 0;
100 	}
101 	spin_unlock(&tiqn->tiqn_state_lock);
102 
103 	return -1;
104 }
105 
106 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
107 {
108 	spin_lock(&tiqn->tiqn_state_lock);
109 	tiqn->tiqn_access_count--;
110 	spin_unlock(&tiqn->tiqn_state_lock);
111 }
112 
113 /*
114  * Note that IQN formatting is expected to be done in userspace, and
115  * no explict IQN format checks are done here.
116  */
117 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
118 {
119 	struct iscsi_tiqn *tiqn = NULL;
120 	int ret;
121 
122 	if (strlen(buf) >= ISCSI_IQN_LEN) {
123 		pr_err("Target IQN exceeds %d bytes\n",
124 				ISCSI_IQN_LEN);
125 		return ERR_PTR(-EINVAL);
126 	}
127 
128 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
129 	if (!tiqn) {
130 		pr_err("Unable to allocate struct iscsi_tiqn\n");
131 		return ERR_PTR(-ENOMEM);
132 	}
133 
134 	sprintf(tiqn->tiqn, "%s", buf);
135 	INIT_LIST_HEAD(&tiqn->tiqn_list);
136 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
137 	spin_lock_init(&tiqn->tiqn_state_lock);
138 	spin_lock_init(&tiqn->tiqn_tpg_lock);
139 	spin_lock_init(&tiqn->sess_err_stats.lock);
140 	spin_lock_init(&tiqn->login_stats.lock);
141 	spin_lock_init(&tiqn->logout_stats.lock);
142 
143 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
144 
145 	idr_preload(GFP_KERNEL);
146 	spin_lock(&tiqn_lock);
147 
148 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
149 	if (ret < 0) {
150 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
151 		spin_unlock(&tiqn_lock);
152 		idr_preload_end();
153 		kfree(tiqn);
154 		return ERR_PTR(ret);
155 	}
156 	tiqn->tiqn_index = ret;
157 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
158 
159 	spin_unlock(&tiqn_lock);
160 	idr_preload_end();
161 
162 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
163 
164 	return tiqn;
165 
166 }
167 
168 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
169 {
170 	/*
171 	 * Wait for accesses to said struct iscsi_tiqn to end.
172 	 */
173 	spin_lock(&tiqn->tiqn_state_lock);
174 	while (tiqn->tiqn_access_count != 0) {
175 		spin_unlock(&tiqn->tiqn_state_lock);
176 		msleep(10);
177 		spin_lock(&tiqn->tiqn_state_lock);
178 	}
179 	spin_unlock(&tiqn->tiqn_state_lock);
180 }
181 
182 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
183 {
184 	/*
185 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
186 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
187 	 * attempts to access this struct iscsi_tiqn will fail from both transport
188 	 * fabric and control code paths.
189 	 */
190 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
191 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
192 		return;
193 	}
194 
195 	iscsit_wait_for_tiqn(tiqn);
196 
197 	spin_lock(&tiqn_lock);
198 	list_del(&tiqn->tiqn_list);
199 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
200 	spin_unlock(&tiqn_lock);
201 
202 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
203 			tiqn->tiqn);
204 	kfree(tiqn);
205 }
206 
207 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
208 {
209 	int ret;
210 	/*
211 	 * Determine if the network portal is accepting storage traffic.
212 	 */
213 	spin_lock_bh(&np->np_thread_lock);
214 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
215 		spin_unlock_bh(&np->np_thread_lock);
216 		return -1;
217 	}
218 	spin_unlock_bh(&np->np_thread_lock);
219 	/*
220 	 * Determine if the portal group is accepting storage traffic.
221 	 */
222 	spin_lock_bh(&tpg->tpg_state_lock);
223 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
224 		spin_unlock_bh(&tpg->tpg_state_lock);
225 		return -1;
226 	}
227 	spin_unlock_bh(&tpg->tpg_state_lock);
228 
229 	/*
230 	 * Here we serialize access across the TIQN+TPG Tuple.
231 	 */
232 	ret = down_interruptible(&tpg->np_login_sem);
233 	if (ret != 0)
234 		return -1;
235 
236 	spin_lock_bh(&tpg->tpg_state_lock);
237 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
238 		spin_unlock_bh(&tpg->tpg_state_lock);
239 		up(&tpg->np_login_sem);
240 		return -1;
241 	}
242 	spin_unlock_bh(&tpg->tpg_state_lock);
243 
244 	return 0;
245 }
246 
247 void iscsit_login_kref_put(struct kref *kref)
248 {
249 	struct iscsi_tpg_np *tpg_np = container_of(kref,
250 				struct iscsi_tpg_np, tpg_np_kref);
251 
252 	complete(&tpg_np->tpg_np_comp);
253 }
254 
255 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
256 		       struct iscsi_tpg_np *tpg_np)
257 {
258 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
259 
260 	up(&tpg->np_login_sem);
261 
262 	if (tpg_np)
263 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
264 
265 	if (tiqn)
266 		iscsit_put_tiqn_for_login(tiqn);
267 
268 	return 0;
269 }
270 
271 bool iscsit_check_np_match(
272 	struct sockaddr_storage *sockaddr,
273 	struct iscsi_np *np,
274 	int network_transport)
275 {
276 	struct sockaddr_in *sock_in, *sock_in_e;
277 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
278 	bool ip_match = false;
279 	u16 port, port_e;
280 
281 	if (sockaddr->ss_family == AF_INET6) {
282 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
283 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
284 
285 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
286 			    &sock_in6_e->sin6_addr.in6_u,
287 			    sizeof(struct in6_addr)))
288 			ip_match = true;
289 
290 		port = ntohs(sock_in6->sin6_port);
291 		port_e = ntohs(sock_in6_e->sin6_port);
292 	} else {
293 		sock_in = (struct sockaddr_in *)sockaddr;
294 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
295 
296 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
297 			ip_match = true;
298 
299 		port = ntohs(sock_in->sin_port);
300 		port_e = ntohs(sock_in_e->sin_port);
301 	}
302 
303 	if (ip_match && (port_e == port) &&
304 	    (np->np_network_transport == network_transport))
305 		return true;
306 
307 	return false;
308 }
309 
310 /*
311  * Called with mutex np_lock held
312  */
313 static struct iscsi_np *iscsit_get_np(
314 	struct sockaddr_storage *sockaddr,
315 	int network_transport)
316 {
317 	struct iscsi_np *np;
318 	bool match;
319 
320 	list_for_each_entry(np, &g_np_list, np_list) {
321 		spin_lock_bh(&np->np_thread_lock);
322 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
323 			spin_unlock_bh(&np->np_thread_lock);
324 			continue;
325 		}
326 
327 		match = iscsit_check_np_match(sockaddr, np, network_transport);
328 		if (match) {
329 			/*
330 			 * Increment the np_exports reference count now to
331 			 * prevent iscsit_del_np() below from being called
332 			 * while iscsi_tpg_add_network_portal() is called.
333 			 */
334 			np->np_exports++;
335 			spin_unlock_bh(&np->np_thread_lock);
336 			return np;
337 		}
338 		spin_unlock_bh(&np->np_thread_lock);
339 	}
340 
341 	return NULL;
342 }
343 
344 struct iscsi_np *iscsit_add_np(
345 	struct sockaddr_storage *sockaddr,
346 	int network_transport)
347 {
348 	struct iscsi_np *np;
349 	int ret;
350 
351 	mutex_lock(&np_lock);
352 
353 	/*
354 	 * Locate the existing struct iscsi_np if already active..
355 	 */
356 	np = iscsit_get_np(sockaddr, network_transport);
357 	if (np) {
358 		mutex_unlock(&np_lock);
359 		return np;
360 	}
361 
362 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
363 	if (!np) {
364 		pr_err("Unable to allocate memory for struct iscsi_np\n");
365 		mutex_unlock(&np_lock);
366 		return ERR_PTR(-ENOMEM);
367 	}
368 
369 	np->np_flags |= NPF_IP_NETWORK;
370 	np->np_network_transport = network_transport;
371 	spin_lock_init(&np->np_thread_lock);
372 	init_completion(&np->np_restart_comp);
373 	INIT_LIST_HEAD(&np->np_list);
374 
375 	ret = iscsi_target_setup_login_socket(np, sockaddr);
376 	if (ret != 0) {
377 		kfree(np);
378 		mutex_unlock(&np_lock);
379 		return ERR_PTR(ret);
380 	}
381 
382 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
383 	if (IS_ERR(np->np_thread)) {
384 		pr_err("Unable to create kthread: iscsi_np\n");
385 		ret = PTR_ERR(np->np_thread);
386 		kfree(np);
387 		mutex_unlock(&np_lock);
388 		return ERR_PTR(ret);
389 	}
390 	/*
391 	 * Increment the np_exports reference count now to prevent
392 	 * iscsit_del_np() below from being run while a new call to
393 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
394 	 * active.  We don't need to hold np->np_thread_lock at this
395 	 * point because iscsi_np has not been added to g_np_list yet.
396 	 */
397 	np->np_exports = 1;
398 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
399 
400 	list_add_tail(&np->np_list, &g_np_list);
401 	mutex_unlock(&np_lock);
402 
403 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
404 		&np->np_sockaddr, np->np_transport->name);
405 
406 	return np;
407 }
408 
409 int iscsit_reset_np_thread(
410 	struct iscsi_np *np,
411 	struct iscsi_tpg_np *tpg_np,
412 	struct iscsi_portal_group *tpg,
413 	bool shutdown)
414 {
415 	spin_lock_bh(&np->np_thread_lock);
416 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
417 		spin_unlock_bh(&np->np_thread_lock);
418 		return 0;
419 	}
420 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
421 
422 	if (np->np_thread) {
423 		spin_unlock_bh(&np->np_thread_lock);
424 		send_sig(SIGINT, np->np_thread, 1);
425 		wait_for_completion(&np->np_restart_comp);
426 		spin_lock_bh(&np->np_thread_lock);
427 	}
428 	spin_unlock_bh(&np->np_thread_lock);
429 
430 	if (tpg_np && shutdown) {
431 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
432 
433 		wait_for_completion(&tpg_np->tpg_np_comp);
434 	}
435 
436 	return 0;
437 }
438 
439 static void iscsit_free_np(struct iscsi_np *np)
440 {
441 	if (np->np_socket)
442 		sock_release(np->np_socket);
443 }
444 
445 int iscsit_del_np(struct iscsi_np *np)
446 {
447 	spin_lock_bh(&np->np_thread_lock);
448 	np->np_exports--;
449 	if (np->np_exports) {
450 		np->enabled = true;
451 		spin_unlock_bh(&np->np_thread_lock);
452 		return 0;
453 	}
454 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
455 	spin_unlock_bh(&np->np_thread_lock);
456 
457 	if (np->np_thread) {
458 		/*
459 		 * We need to send the signal to wakeup Linux/Net
460 		 * which may be sleeping in sock_accept()..
461 		 */
462 		send_sig(SIGINT, np->np_thread, 1);
463 		kthread_stop(np->np_thread);
464 		np->np_thread = NULL;
465 	}
466 
467 	np->np_transport->iscsit_free_np(np);
468 
469 	mutex_lock(&np_lock);
470 	list_del(&np->np_list);
471 	mutex_unlock(&np_lock);
472 
473 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
474 		&np->np_sockaddr, np->np_transport->name);
475 
476 	iscsit_put_transport(np->np_transport);
477 	kfree(np);
478 	return 0;
479 }
480 
481 static int iscsit_immediate_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
482 static int iscsit_response_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
483 
484 static int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
485 {
486 	iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
487 	return 0;
488 }
489 
490 static void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
491 {
492 	bool scsi_cmd = (cmd->iscsi_opcode == ISCSI_OP_SCSI_CMD);
493 
494 	spin_lock_bh(&conn->cmd_lock);
495 	if (!list_empty(&cmd->i_conn_node))
496 		list_del_init(&cmd->i_conn_node);
497 	spin_unlock_bh(&conn->cmd_lock);
498 
499 	__iscsit_free_cmd(cmd, scsi_cmd, true);
500 }
501 
502 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
503 {
504 	return TARGET_PROT_NORMAL;
505 }
506 
507 static struct iscsit_transport iscsi_target_transport = {
508 	.name			= "iSCSI/TCP",
509 	.transport_type		= ISCSI_TCP,
510 	.owner			= NULL,
511 	.iscsit_setup_np	= iscsit_setup_np,
512 	.iscsit_accept_np	= iscsit_accept_np,
513 	.iscsit_free_np		= iscsit_free_np,
514 	.iscsit_get_login_rx	= iscsit_get_login_rx,
515 	.iscsit_put_login_tx	= iscsit_put_login_tx,
516 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
517 	.iscsit_immediate_queue	= iscsit_immediate_queue,
518 	.iscsit_response_queue	= iscsit_response_queue,
519 	.iscsit_queue_data_in	= iscsit_queue_rsp,
520 	.iscsit_queue_status	= iscsit_queue_rsp,
521 	.iscsit_aborted_task	= iscsit_aborted_task,
522 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
523 };
524 
525 static int __init iscsi_target_init_module(void)
526 {
527 	int ret = 0, size;
528 
529 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
530 
531 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
532 	if (!iscsit_global) {
533 		pr_err("Unable to allocate memory for iscsit_global\n");
534 		return -1;
535 	}
536 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
537 	mutex_init(&auth_id_lock);
538 	spin_lock_init(&sess_idr_lock);
539 	idr_init(&tiqn_idr);
540 	idr_init(&sess_idr);
541 
542 	ret = target_register_template(&iscsi_ops);
543 	if (ret)
544 		goto out;
545 
546 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
547 	iscsit_global->ts_bitmap = vzalloc(size);
548 	if (!iscsit_global->ts_bitmap) {
549 		pr_err("Unable to allocate iscsit_global->ts_bitmap\n");
550 		goto configfs_out;
551 	}
552 
553 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
554 			sizeof(struct iscsi_queue_req),
555 			__alignof__(struct iscsi_queue_req), 0, NULL);
556 	if (!lio_qr_cache) {
557 		pr_err("nable to kmem_cache_create() for"
558 				" lio_qr_cache\n");
559 		goto bitmap_out;
560 	}
561 
562 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
563 			sizeof(struct iscsi_datain_req),
564 			__alignof__(struct iscsi_datain_req), 0, NULL);
565 	if (!lio_dr_cache) {
566 		pr_err("Unable to kmem_cache_create() for"
567 				" lio_dr_cache\n");
568 		goto qr_out;
569 	}
570 
571 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
572 			sizeof(struct iscsi_ooo_cmdsn),
573 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
574 	if (!lio_ooo_cache) {
575 		pr_err("Unable to kmem_cache_create() for"
576 				" lio_ooo_cache\n");
577 		goto dr_out;
578 	}
579 
580 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
581 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
582 			0, NULL);
583 	if (!lio_r2t_cache) {
584 		pr_err("Unable to kmem_cache_create() for"
585 				" lio_r2t_cache\n");
586 		goto ooo_out;
587 	}
588 
589 	iscsit_register_transport(&iscsi_target_transport);
590 
591 	if (iscsit_load_discovery_tpg() < 0)
592 		goto r2t_out;
593 
594 	return ret;
595 r2t_out:
596 	iscsit_unregister_transport(&iscsi_target_transport);
597 	kmem_cache_destroy(lio_r2t_cache);
598 ooo_out:
599 	kmem_cache_destroy(lio_ooo_cache);
600 dr_out:
601 	kmem_cache_destroy(lio_dr_cache);
602 qr_out:
603 	kmem_cache_destroy(lio_qr_cache);
604 bitmap_out:
605 	vfree(iscsit_global->ts_bitmap);
606 configfs_out:
607 	/* XXX: this probably wants it to be it's own unwind step.. */
608 	if (iscsit_global->discovery_tpg)
609 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
610 	target_unregister_template(&iscsi_ops);
611 out:
612 	kfree(iscsit_global);
613 	return -ENOMEM;
614 }
615 
616 static void __exit iscsi_target_cleanup_module(void)
617 {
618 	iscsit_release_discovery_tpg();
619 	iscsit_unregister_transport(&iscsi_target_transport);
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 	/*
626 	 * Shutdown discovery sessions and disable discovery TPG
627 	 */
628 	if (iscsit_global->discovery_tpg)
629 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
630 
631 	target_unregister_template(&iscsi_ops);
632 
633 	vfree(iscsit_global->ts_bitmap);
634 	kfree(iscsit_global);
635 }
636 
637 static int iscsit_add_reject(
638 	struct iscsi_conn *conn,
639 	u8 reason,
640 	unsigned char *buf)
641 {
642 	struct iscsi_cmd *cmd;
643 
644 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
645 	if (!cmd)
646 		return -1;
647 
648 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
649 	cmd->reject_reason = reason;
650 
651 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
652 	if (!cmd->buf_ptr) {
653 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
654 		iscsit_free_cmd(cmd, false);
655 		return -1;
656 	}
657 
658 	spin_lock_bh(&conn->cmd_lock);
659 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
660 	spin_unlock_bh(&conn->cmd_lock);
661 
662 	cmd->i_state = ISTATE_SEND_REJECT;
663 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
664 
665 	return -1;
666 }
667 
668 static int iscsit_add_reject_from_cmd(
669 	struct iscsi_cmd *cmd,
670 	u8 reason,
671 	bool add_to_conn,
672 	unsigned char *buf)
673 {
674 	struct iscsi_conn *conn;
675 
676 	if (!cmd->conn) {
677 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
678 				cmd->init_task_tag);
679 		return -1;
680 	}
681 	conn = cmd->conn;
682 
683 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
684 	cmd->reject_reason = reason;
685 
686 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
687 	if (!cmd->buf_ptr) {
688 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
689 		iscsit_free_cmd(cmd, false);
690 		return -1;
691 	}
692 
693 	if (add_to_conn) {
694 		spin_lock_bh(&conn->cmd_lock);
695 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
696 		spin_unlock_bh(&conn->cmd_lock);
697 	}
698 
699 	cmd->i_state = ISTATE_SEND_REJECT;
700 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
701 	/*
702 	 * Perform the kref_put now if se_cmd has already been setup by
703 	 * scsit_setup_scsi_cmd()
704 	 */
705 	if (cmd->se_cmd.se_tfo != NULL) {
706 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
707 		target_put_sess_cmd(&cmd->se_cmd);
708 	}
709 	return -1;
710 }
711 
712 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
713 				 unsigned char *buf)
714 {
715 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
716 }
717 
718 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
719 {
720 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
721 }
722 
723 /*
724  * Map some portion of the allocated scatterlist to an iovec, suitable for
725  * kernel sockets to copy data in/out.
726  */
727 static int iscsit_map_iovec(
728 	struct iscsi_cmd *cmd,
729 	struct kvec *iov,
730 	u32 data_offset,
731 	u32 data_length)
732 {
733 	u32 i = 0;
734 	struct scatterlist *sg;
735 	unsigned int page_off;
736 
737 	/*
738 	 * We know each entry in t_data_sg contains a page.
739 	 */
740 	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
741 	page_off = (data_offset % PAGE_SIZE);
742 
743 	cmd->first_data_sg = sg;
744 	cmd->first_data_sg_off = page_off;
745 
746 	while (data_length) {
747 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
748 
749 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
750 		iov[i].iov_len = cur_len;
751 
752 		data_length -= cur_len;
753 		page_off = 0;
754 		sg = sg_next(sg);
755 		i++;
756 	}
757 
758 	cmd->kmapped_nents = i;
759 
760 	return i;
761 }
762 
763 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
764 {
765 	u32 i;
766 	struct scatterlist *sg;
767 
768 	sg = cmd->first_data_sg;
769 
770 	for (i = 0; i < cmd->kmapped_nents; i++)
771 		kunmap(sg_page(&sg[i]));
772 }
773 
774 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
775 {
776 	LIST_HEAD(ack_list);
777 	struct iscsi_cmd *cmd, *cmd_p;
778 
779 	conn->exp_statsn = exp_statsn;
780 
781 	if (conn->sess->sess_ops->RDMAExtensions)
782 		return;
783 
784 	spin_lock_bh(&conn->cmd_lock);
785 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
786 		spin_lock(&cmd->istate_lock);
787 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
788 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
789 			cmd->i_state = ISTATE_REMOVE;
790 			spin_unlock(&cmd->istate_lock);
791 			list_move_tail(&cmd->i_conn_node, &ack_list);
792 			continue;
793 		}
794 		spin_unlock(&cmd->istate_lock);
795 	}
796 	spin_unlock_bh(&conn->cmd_lock);
797 
798 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
799 		list_del_init(&cmd->i_conn_node);
800 		iscsit_free_cmd(cmd, false);
801 	}
802 }
803 
804 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
805 {
806 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
807 
808 	iov_count += ISCSI_IOV_DATA_BUFFER;
809 
810 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
811 	if (!cmd->iov_data) {
812 		pr_err("Unable to allocate cmd->iov_data\n");
813 		return -ENOMEM;
814 	}
815 
816 	cmd->orig_iov_data_count = iov_count;
817 	return 0;
818 }
819 
820 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
821 			  unsigned char *buf)
822 {
823 	int data_direction, payload_length;
824 	struct iscsi_scsi_req *hdr;
825 	int iscsi_task_attr;
826 	int sam_task_attr;
827 
828 	atomic_long_inc(&conn->sess->cmd_pdus);
829 
830 	hdr			= (struct iscsi_scsi_req *) buf;
831 	payload_length		= ntoh24(hdr->dlength);
832 
833 	/* FIXME; Add checks for AdditionalHeaderSegment */
834 
835 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
836 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
837 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
838 				" not set. Bad iSCSI Initiator.\n");
839 		return iscsit_add_reject_cmd(cmd,
840 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
841 	}
842 
843 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
844 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
845 		/*
846 		 * From RFC-3720 Section 10.3.1:
847 		 *
848 		 * "Either or both of R and W MAY be 1 when either the
849 		 *  Expected Data Transfer Length and/or Bidirectional Read
850 		 *  Expected Data Transfer Length are 0"
851 		 *
852 		 * For this case, go ahead and clear the unnecssary bits
853 		 * to avoid any confusion with ->data_direction.
854 		 */
855 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
856 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
857 
858 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
859 			" set when Expected Data Transfer Length is 0 for"
860 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
861 	}
862 
863 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
864 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
865 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
866 			" MUST be set if Expected Data Transfer Length is not 0."
867 			" Bad iSCSI Initiator\n");
868 		return iscsit_add_reject_cmd(cmd,
869 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
870 	}
871 
872 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
873 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
874 		pr_err("Bidirectional operations not supported!\n");
875 		return iscsit_add_reject_cmd(cmd,
876 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
877 	}
878 
879 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
880 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
881 				" Scsi Command PDU.\n");
882 		return iscsit_add_reject_cmd(cmd,
883 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
884 	}
885 
886 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
887 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
888 			" protocol error.\n", payload_length);
889 		return iscsit_add_reject_cmd(cmd,
890 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
891 	}
892 
893 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
894 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
895 		pr_err("Expected Data Transfer Length and Length of"
896 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
897 			" bit is not set protocol error\n");
898 		return iscsit_add_reject_cmd(cmd,
899 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
900 	}
901 
902 	if (payload_length > be32_to_cpu(hdr->data_length)) {
903 		pr_err("DataSegmentLength: %u is greater than"
904 			" EDTL: %u, protocol error.\n", payload_length,
905 				hdr->data_length);
906 		return iscsit_add_reject_cmd(cmd,
907 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
908 	}
909 
910 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
911 		pr_err("DataSegmentLength: %u is greater than"
912 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
913 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
914 		return iscsit_add_reject_cmd(cmd,
915 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
916 	}
917 
918 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
919 		pr_err("DataSegmentLength: %u is greater than"
920 			" FirstBurstLength: %u, protocol error.\n",
921 			payload_length, conn->sess->sess_ops->FirstBurstLength);
922 		return iscsit_add_reject_cmd(cmd,
923 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
924 	}
925 
926 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
927 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
928 			  DMA_NONE;
929 
930 	cmd->data_direction = data_direction;
931 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
932 	/*
933 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
934 	 */
935 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
936 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
937 		sam_task_attr = TCM_SIMPLE_TAG;
938 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
939 		sam_task_attr = TCM_ORDERED_TAG;
940 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
941 		sam_task_attr = TCM_HEAD_TAG;
942 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
943 		sam_task_attr = TCM_ACA_TAG;
944 	else {
945 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
946 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
947 		sam_task_attr = TCM_SIMPLE_TAG;
948 	}
949 
950 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
951 	cmd->i_state		= ISTATE_NEW_CMD;
952 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
953 	cmd->immediate_data	= (payload_length) ? 1 : 0;
954 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
955 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
956 	if (cmd->unsolicited_data)
957 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
958 
959 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
960 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
961 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
962 	else
963 		cmd->targ_xfer_tag = 0xFFFFFFFF;
964 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
965 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
966 	cmd->first_burst_len	= payload_length;
967 
968 	if (!conn->sess->sess_ops->RDMAExtensions &&
969 	     cmd->data_direction == DMA_FROM_DEVICE) {
970 		struct iscsi_datain_req *dr;
971 
972 		dr = iscsit_allocate_datain_req();
973 		if (!dr)
974 			return iscsit_add_reject_cmd(cmd,
975 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
976 
977 		iscsit_attach_datain_req(cmd, dr);
978 	}
979 
980 	/*
981 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
982 	 */
983 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
984 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
985 			cmd->data_direction, sam_task_attr,
986 			cmd->sense_buffer + 2);
987 
988 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
989 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
990 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
991 		conn->cid);
992 
993 	target_get_sess_cmd(&cmd->se_cmd, true);
994 
995 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
996 						     scsilun_to_int(&hdr->lun));
997 	if (cmd->sense_reason)
998 		goto attach_cmd;
999 
1000 	/* only used for printks or comparing with ->ref_task_tag */
1001 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1002 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
1003 	if (cmd->sense_reason) {
1004 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1005 			return iscsit_add_reject_cmd(cmd,
1006 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1007 		}
1008 
1009 		goto attach_cmd;
1010 	}
1011 
1012 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1013 		return iscsit_add_reject_cmd(cmd,
1014 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1015 	}
1016 
1017 attach_cmd:
1018 	spin_lock_bh(&conn->cmd_lock);
1019 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1020 	spin_unlock_bh(&conn->cmd_lock);
1021 	/*
1022 	 * Check if we need to delay processing because of ALUA
1023 	 * Active/NonOptimized primary access state..
1024 	 */
1025 	core_alua_check_nonop_delay(&cmd->se_cmd);
1026 
1027 	return 0;
1028 }
1029 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1030 
1031 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1032 {
1033 	iscsit_set_dataout_sequence_values(cmd);
1034 
1035 	spin_lock_bh(&cmd->dataout_timeout_lock);
1036 	iscsit_start_dataout_timer(cmd, cmd->conn);
1037 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1038 }
1039 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1040 
1041 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1042 			    struct iscsi_scsi_req *hdr)
1043 {
1044 	int cmdsn_ret = 0;
1045 	/*
1046 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1047 	 * the Immediate Bit is not set, and no Immediate
1048 	 * Data is attached.
1049 	 *
1050 	 * A PDU/CmdSN carrying Immediate Data can only
1051 	 * be processed after the DataCRC has passed.
1052 	 * If the DataCRC fails, the CmdSN MUST NOT
1053 	 * be acknowledged. (See below)
1054 	 */
1055 	if (!cmd->immediate_data) {
1056 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1057 					(unsigned char *)hdr, hdr->cmdsn);
1058 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1059 			return -1;
1060 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1061 			target_put_sess_cmd(&cmd->se_cmd);
1062 			return 0;
1063 		}
1064 	}
1065 
1066 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1067 
1068 	/*
1069 	 * If no Immediate Data is attached, it's OK to return now.
1070 	 */
1071 	if (!cmd->immediate_data) {
1072 		if (!cmd->sense_reason && cmd->unsolicited_data)
1073 			iscsit_set_unsoliticed_dataout(cmd);
1074 		if (!cmd->sense_reason)
1075 			return 0;
1076 
1077 		target_put_sess_cmd(&cmd->se_cmd);
1078 		return 0;
1079 	}
1080 
1081 	/*
1082 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1083 	 * execution.  These exceptions are processed in CmdSN order using
1084 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1085 	 */
1086 	if (cmd->sense_reason) {
1087 		if (cmd->reject_reason)
1088 			return 0;
1089 
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 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1109 	/*
1110 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1111 	 */
1112 	if (dump_payload)
1113 		goto after_immediate_data;
1114 
1115 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1116 					cmd->first_burst_len);
1117 after_immediate_data:
1118 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1119 		/*
1120 		 * A PDU/CmdSN carrying Immediate Data passed
1121 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1122 		 * Immediate Bit is not set.
1123 		 */
1124 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1125 					(unsigned char *)hdr, hdr->cmdsn);
1126 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1127 			return -1;
1128 
1129 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1130 			int rc;
1131 
1132 			rc = iscsit_dump_data_payload(cmd->conn,
1133 						      cmd->first_burst_len, 1);
1134 			target_put_sess_cmd(&cmd->se_cmd);
1135 			return rc;
1136 		} else if (cmd->unsolicited_data)
1137 			iscsit_set_unsoliticed_dataout(cmd);
1138 
1139 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1140 		/*
1141 		 * Immediate Data failed DataCRC and ERL>=1,
1142 		 * silently drop this PDU and let the initiator
1143 		 * plug the CmdSN gap.
1144 		 *
1145 		 * FIXME: Send Unsolicited NOPIN with reserved
1146 		 * TTT here to help the initiator figure out
1147 		 * the missing CmdSN, although they should be
1148 		 * intelligent enough to determine the missing
1149 		 * CmdSN and issue a retry to plug the sequence.
1150 		 */
1151 		cmd->i_state = ISTATE_REMOVE;
1152 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1153 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1154 		return -1;
1155 
1156 	return 0;
1157 }
1158 
1159 static int
1160 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1161 			   unsigned char *buf)
1162 {
1163 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1164 	int rc, immed_data;
1165 	bool dump_payload = false;
1166 
1167 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1168 	if (rc < 0)
1169 		return 0;
1170 	/*
1171 	 * Allocation iovecs needed for struct socket operations for
1172 	 * traditional iSCSI block I/O.
1173 	 */
1174 	if (iscsit_allocate_iovecs(cmd) < 0) {
1175 		return iscsit_reject_cmd(cmd,
1176 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1177 	}
1178 	immed_data = cmd->immediate_data;
1179 
1180 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1181 	if (rc < 0)
1182 		return rc;
1183 	else if (rc > 0)
1184 		dump_payload = true;
1185 
1186 	if (!immed_data)
1187 		return 0;
1188 
1189 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1190 }
1191 
1192 static u32 iscsit_do_crypto_hash_sg(
1193 	struct ahash_request *hash,
1194 	struct iscsi_cmd *cmd,
1195 	u32 data_offset,
1196 	u32 data_length,
1197 	u32 padding,
1198 	u8 *pad_bytes)
1199 {
1200 	u32 data_crc;
1201 	struct scatterlist *sg;
1202 	unsigned int page_off;
1203 
1204 	crypto_ahash_init(hash);
1205 
1206 	sg = cmd->first_data_sg;
1207 	page_off = cmd->first_data_sg_off;
1208 
1209 	while (data_length) {
1210 		u32 cur_len = min_t(u32, data_length, (sg->length - page_off));
1211 
1212 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1213 		crypto_ahash_update(hash);
1214 
1215 		data_length -= cur_len;
1216 		page_off = 0;
1217 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1218 		sg = sg_next(sg);
1219 	}
1220 
1221 	if (padding) {
1222 		struct scatterlist pad_sg;
1223 
1224 		sg_init_one(&pad_sg, pad_bytes, padding);
1225 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1226 					padding);
1227 		crypto_ahash_finup(hash);
1228 	} else {
1229 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1230 		crypto_ahash_final(hash);
1231 	}
1232 
1233 	return data_crc;
1234 }
1235 
1236 static void iscsit_do_crypto_hash_buf(
1237 	struct ahash_request *hash,
1238 	const void *buf,
1239 	u32 payload_length,
1240 	u32 padding,
1241 	u8 *pad_bytes,
1242 	u8 *data_crc)
1243 {
1244 	struct scatterlist sg[2];
1245 
1246 	sg_init_table(sg, ARRAY_SIZE(sg));
1247 	sg_set_buf(sg, buf, payload_length);
1248 	sg_set_buf(sg + 1, pad_bytes, padding);
1249 
1250 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1251 
1252 	crypto_ahash_digest(hash);
1253 }
1254 
1255 int
1256 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1257 			  struct iscsi_cmd **out_cmd)
1258 {
1259 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1260 	struct iscsi_cmd *cmd = NULL;
1261 	struct se_cmd *se_cmd;
1262 	u32 payload_length = ntoh24(hdr->dlength);
1263 	int rc;
1264 
1265 	if (!payload_length) {
1266 		pr_warn("DataOUT payload is ZERO, ignoring.\n");
1267 		return 0;
1268 	}
1269 
1270 	/* iSCSI write */
1271 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1272 
1273 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1274 		pr_err("DataSegmentLength: %u is greater than"
1275 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1276 			conn->conn_ops->MaxXmitDataSegmentLength);
1277 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1278 					 buf);
1279 	}
1280 
1281 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1282 			payload_length);
1283 	if (!cmd)
1284 		return 0;
1285 
1286 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1287 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1288 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1289 		payload_length, conn->cid);
1290 
1291 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1292 		pr_err("Command ITT: 0x%08x received DataOUT after"
1293 			" last DataOUT received, dumping payload\n",
1294 			cmd->init_task_tag);
1295 		return iscsit_dump_data_payload(conn, payload_length, 1);
1296 	}
1297 
1298 	if (cmd->data_direction != DMA_TO_DEVICE) {
1299 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1300 			" NON-WRITE command.\n", cmd->init_task_tag);
1301 		return iscsit_dump_data_payload(conn, payload_length, 1);
1302 	}
1303 	se_cmd = &cmd->se_cmd;
1304 	iscsit_mod_dataout_timer(cmd);
1305 
1306 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1307 		pr_err("DataOut Offset: %u, Length %u greater than"
1308 			" iSCSI Command EDTL %u, protocol error.\n",
1309 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1310 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1311 	}
1312 
1313 	if (cmd->unsolicited_data) {
1314 		int dump_unsolicited_data = 0;
1315 
1316 		if (conn->sess->sess_ops->InitialR2T) {
1317 			pr_err("Received unexpected unsolicited data"
1318 				" while InitialR2T=Yes, protocol error.\n");
1319 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1320 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1321 			return -1;
1322 		}
1323 		/*
1324 		 * Special case for dealing with Unsolicited DataOUT
1325 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1326 		 * failures;
1327 		 */
1328 
1329 		/* Something's amiss if we're not in WRITE_PENDING state... */
1330 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1331 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1332 			dump_unsolicited_data = 1;
1333 
1334 		if (dump_unsolicited_data) {
1335 			/*
1336 			 * Check if a delayed TASK_ABORTED status needs to
1337 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1338 			 * received with the unsolicited data out.
1339 			 */
1340 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1341 				iscsit_stop_dataout_timer(cmd);
1342 
1343 			transport_check_aborted_status(se_cmd,
1344 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1345 			return iscsit_dump_data_payload(conn, payload_length, 1);
1346 		}
1347 	} else {
1348 		/*
1349 		 * For the normal solicited data path:
1350 		 *
1351 		 * Check for a delayed TASK_ABORTED status and dump any
1352 		 * incoming data out payload if one exists.  Also, when the
1353 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1354 		 * data out sequence, we decrement outstanding_r2ts.  Once
1355 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1356 		 * TASK_ABORTED status.
1357 		 */
1358 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1359 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1360 				if (--cmd->outstanding_r2ts < 1) {
1361 					iscsit_stop_dataout_timer(cmd);
1362 					transport_check_aborted_status(
1363 							se_cmd, 1);
1364 				}
1365 
1366 			return iscsit_dump_data_payload(conn, payload_length, 1);
1367 		}
1368 	}
1369 	/*
1370 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1371 	 * within-command recovery checks before receiving the payload.
1372 	 */
1373 	rc = iscsit_check_pre_dataout(cmd, buf);
1374 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1375 		return 0;
1376 	else if (rc == DATAOUT_CANNOT_RECOVER)
1377 		return -1;
1378 
1379 	*out_cmd = cmd;
1380 	return 0;
1381 }
1382 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1383 
1384 static int
1385 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1386 		   struct iscsi_data *hdr)
1387 {
1388 	struct kvec *iov;
1389 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1390 	u32 payload_length = ntoh24(hdr->dlength);
1391 	int iov_ret, data_crc_failed = 0;
1392 
1393 	rx_size += payload_length;
1394 	iov = &cmd->iov_data[0];
1395 
1396 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1397 				   payload_length);
1398 	if (iov_ret < 0)
1399 		return -1;
1400 
1401 	iov_count += iov_ret;
1402 
1403 	padding = ((-payload_length) & 3);
1404 	if (padding != 0) {
1405 		iov[iov_count].iov_base	= cmd->pad_bytes;
1406 		iov[iov_count++].iov_len = padding;
1407 		rx_size += padding;
1408 		pr_debug("Receiving %u padding bytes.\n", padding);
1409 	}
1410 
1411 	if (conn->conn_ops->DataDigest) {
1412 		iov[iov_count].iov_base = &checksum;
1413 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1414 		rx_size += ISCSI_CRC_LEN;
1415 	}
1416 
1417 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1418 
1419 	iscsit_unmap_iovec(cmd);
1420 
1421 	if (rx_got != rx_size)
1422 		return -1;
1423 
1424 	if (conn->conn_ops->DataDigest) {
1425 		u32 data_crc;
1426 
1427 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1428 						    be32_to_cpu(hdr->offset),
1429 						    payload_length, padding,
1430 						    cmd->pad_bytes);
1431 
1432 		if (checksum != data_crc) {
1433 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1434 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1435 				" does not match computed 0x%08x\n",
1436 				hdr->itt, hdr->offset, payload_length,
1437 				hdr->datasn, checksum, data_crc);
1438 			data_crc_failed = 1;
1439 		} else {
1440 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1441 				" %u bytes of Data Out\n", checksum,
1442 				payload_length);
1443 		}
1444 	}
1445 
1446 	return data_crc_failed;
1447 }
1448 
1449 int
1450 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1451 			     bool data_crc_failed)
1452 {
1453 	struct iscsi_conn *conn = cmd->conn;
1454 	int rc, ooo_cmdsn;
1455 	/*
1456 	 * Increment post receive data and CRC values or perform
1457 	 * within-command recovery.
1458 	 */
1459 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1460 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1461 		return 0;
1462 	else if (rc == DATAOUT_SEND_R2T) {
1463 		iscsit_set_dataout_sequence_values(cmd);
1464 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1465 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1466 		/*
1467 		 * Handle extra special case for out of order
1468 		 * Unsolicited Data Out.
1469 		 */
1470 		spin_lock_bh(&cmd->istate_lock);
1471 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1472 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1473 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1474 		spin_unlock_bh(&cmd->istate_lock);
1475 
1476 		iscsit_stop_dataout_timer(cmd);
1477 		if (ooo_cmdsn)
1478 			return 0;
1479 		target_execute_cmd(&cmd->se_cmd);
1480 		return 0;
1481 	} else /* DATAOUT_CANNOT_RECOVER */
1482 		return -1;
1483 
1484 	return 0;
1485 }
1486 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1487 
1488 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1489 {
1490 	struct iscsi_cmd *cmd = NULL;
1491 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1492 	int rc;
1493 	bool data_crc_failed = false;
1494 
1495 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1496 	if (rc < 0)
1497 		return 0;
1498 	else if (!cmd)
1499 		return 0;
1500 
1501 	rc = iscsit_get_dataout(conn, cmd, hdr);
1502 	if (rc < 0)
1503 		return rc;
1504 	else if (rc > 0)
1505 		data_crc_failed = true;
1506 
1507 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1508 }
1509 
1510 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1511 			 struct iscsi_nopout *hdr)
1512 {
1513 	u32 payload_length = ntoh24(hdr->dlength);
1514 
1515 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1516 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1517 		if (!cmd)
1518 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1519 						 (unsigned char *)hdr);
1520 
1521 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1522 					 (unsigned char *)hdr);
1523 	}
1524 
1525 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1526 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1527 			" not set, protocol error.\n");
1528 		if (!cmd)
1529 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1530 						 (unsigned char *)hdr);
1531 
1532 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1533 					 (unsigned char *)hdr);
1534 	}
1535 
1536 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1537 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1538 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1539 			" error.\n", payload_length,
1540 			conn->conn_ops->MaxXmitDataSegmentLength);
1541 		if (!cmd)
1542 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1543 						 (unsigned char *)hdr);
1544 
1545 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1546 					 (unsigned char *)hdr);
1547 	}
1548 
1549 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1550 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1551 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1552 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1553 		payload_length);
1554 	/*
1555 	 * This is not a response to a Unsolicited NopIN, which means
1556 	 * it can either be a NOPOUT ping request (with a valid ITT),
1557 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1558 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1559 	 * can contain ping data.
1560 	 */
1561 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1562 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1563 		cmd->i_state		= ISTATE_SEND_NOPIN;
1564 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1565 						1 : 0);
1566 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1567 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1568 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1569 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1570 		cmd->data_direction	= DMA_NONE;
1571 	}
1572 
1573 	return 0;
1574 }
1575 EXPORT_SYMBOL(iscsit_setup_nop_out);
1576 
1577 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1578 			   struct iscsi_nopout *hdr)
1579 {
1580 	struct iscsi_cmd *cmd_p = NULL;
1581 	int cmdsn_ret = 0;
1582 	/*
1583 	 * Initiator is expecting a NopIN ping reply..
1584 	 */
1585 	if (hdr->itt != RESERVED_ITT) {
1586 		if (!cmd)
1587 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1588 						(unsigned char *)hdr);
1589 
1590 		spin_lock_bh(&conn->cmd_lock);
1591 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1592 		spin_unlock_bh(&conn->cmd_lock);
1593 
1594 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1595 
1596 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1597 			iscsit_add_cmd_to_response_queue(cmd, conn,
1598 							 cmd->i_state);
1599 			return 0;
1600 		}
1601 
1602 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1603 				(unsigned char *)hdr, hdr->cmdsn);
1604                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1605 			return 0;
1606 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1607 			return -1;
1608 
1609 		return 0;
1610 	}
1611 	/*
1612 	 * This was a response to a unsolicited NOPIN ping.
1613 	 */
1614 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1615 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1616 		if (!cmd_p)
1617 			return -EINVAL;
1618 
1619 		iscsit_stop_nopin_response_timer(conn);
1620 
1621 		cmd_p->i_state = ISTATE_REMOVE;
1622 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1623 
1624 		iscsit_start_nopin_timer(conn);
1625 		return 0;
1626 	}
1627 	/*
1628 	 * Otherwise, initiator is not expecting a NOPIN is response.
1629 	 * Just ignore for now.
1630 	 */
1631         return 0;
1632 }
1633 EXPORT_SYMBOL(iscsit_process_nop_out);
1634 
1635 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1636 				 unsigned char *buf)
1637 {
1638 	unsigned char *ping_data = NULL;
1639 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1640 	struct kvec *iov = NULL;
1641 	u32 payload_length = ntoh24(hdr->dlength);
1642 	int ret;
1643 
1644 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1645 	if (ret < 0)
1646 		return 0;
1647 	/*
1648 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1649 	 */
1650 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1651 		u32 checksum, data_crc, padding = 0;
1652 		int niov = 0, rx_got, rx_size = payload_length;
1653 
1654 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1655 		if (!ping_data) {
1656 			pr_err("Unable to allocate memory for"
1657 				" NOPOUT ping data.\n");
1658 			ret = -1;
1659 			goto out;
1660 		}
1661 
1662 		iov = &cmd->iov_misc[0];
1663 		iov[niov].iov_base	= ping_data;
1664 		iov[niov++].iov_len	= payload_length;
1665 
1666 		padding = ((-payload_length) & 3);
1667 		if (padding != 0) {
1668 			pr_debug("Receiving %u additional bytes"
1669 				" for padding.\n", padding);
1670 			iov[niov].iov_base	= &cmd->pad_bytes;
1671 			iov[niov++].iov_len	= padding;
1672 			rx_size += padding;
1673 		}
1674 		if (conn->conn_ops->DataDigest) {
1675 			iov[niov].iov_base	= &checksum;
1676 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1677 			rx_size += ISCSI_CRC_LEN;
1678 		}
1679 
1680 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1681 		if (rx_got != rx_size) {
1682 			ret = -1;
1683 			goto out;
1684 		}
1685 
1686 		if (conn->conn_ops->DataDigest) {
1687 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
1688 					ping_data, payload_length,
1689 					padding, cmd->pad_bytes,
1690 					(u8 *)&data_crc);
1691 
1692 			if (checksum != data_crc) {
1693 				pr_err("Ping data CRC32C DataDigest"
1694 				" 0x%08x does not match computed 0x%08x\n",
1695 					checksum, data_crc);
1696 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1697 					pr_err("Unable to recover from"
1698 					" NOPOUT Ping DataCRC failure while in"
1699 						" ERL=0.\n");
1700 					ret = -1;
1701 					goto out;
1702 				} else {
1703 					/*
1704 					 * Silently drop this PDU and let the
1705 					 * initiator plug the CmdSN gap.
1706 					 */
1707 					pr_debug("Dropping NOPOUT"
1708 					" Command CmdSN: 0x%08x due to"
1709 					" DataCRC error.\n", hdr->cmdsn);
1710 					ret = 0;
1711 					goto out;
1712 				}
1713 			} else {
1714 				pr_debug("Got CRC32C DataDigest"
1715 				" 0x%08x for %u bytes of ping data.\n",
1716 					checksum, payload_length);
1717 			}
1718 		}
1719 
1720 		ping_data[payload_length] = '\0';
1721 		/*
1722 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1723 		 */
1724 		cmd->buf_ptr = ping_data;
1725 		cmd->buf_ptr_size = payload_length;
1726 
1727 		pr_debug("Got %u bytes of NOPOUT ping"
1728 			" data.\n", payload_length);
1729 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1730 	}
1731 
1732 	return iscsit_process_nop_out(conn, cmd, hdr);
1733 out:
1734 	if (cmd)
1735 		iscsit_free_cmd(cmd, false);
1736 
1737 	kfree(ping_data);
1738 	return ret;
1739 }
1740 
1741 int
1742 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1743 			   unsigned char *buf)
1744 {
1745 	struct se_tmr_req *se_tmr;
1746 	struct iscsi_tmr_req *tmr_req;
1747 	struct iscsi_tm *hdr;
1748 	int out_of_order_cmdsn = 0, ret;
1749 	bool sess_ref = false;
1750 	u8 function;
1751 
1752 	hdr			= (struct iscsi_tm *) buf;
1753 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1754 	function = hdr->flags;
1755 
1756 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1757 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1758 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1759 		hdr->rtt, hdr->refcmdsn, conn->cid);
1760 
1761 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1762 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1763 	     hdr->rtt != RESERVED_ITT)) {
1764 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1765 		hdr->rtt = RESERVED_ITT;
1766 	}
1767 
1768 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1769 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1770 		pr_err("Task Management Request TASK_REASSIGN not"
1771 			" issued as immediate command, bad iSCSI Initiator"
1772 				"implementation\n");
1773 		return iscsit_add_reject_cmd(cmd,
1774 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1775 	}
1776 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1777 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1778 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1779 
1780 	cmd->data_direction = DMA_NONE;
1781 
1782 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1783 	if (!cmd->tmr_req) {
1784 		pr_err("Unable to allocate memory for"
1785 			" Task Management command!\n");
1786 		return iscsit_add_reject_cmd(cmd,
1787 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1788 					     buf);
1789 	}
1790 
1791 	/*
1792 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1793 	 * LIO-Target $FABRIC_MOD
1794 	 */
1795 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1796 
1797 		u8 tcm_function;
1798 		int ret;
1799 
1800 		transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1801 				      conn->sess->se_sess, 0, DMA_NONE,
1802 				      TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
1803 
1804 		target_get_sess_cmd(&cmd->se_cmd, true);
1805 		sess_ref = true;
1806 
1807 		switch (function) {
1808 		case ISCSI_TM_FUNC_ABORT_TASK:
1809 			tcm_function = TMR_ABORT_TASK;
1810 			break;
1811 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1812 			tcm_function = TMR_ABORT_TASK_SET;
1813 			break;
1814 		case ISCSI_TM_FUNC_CLEAR_ACA:
1815 			tcm_function = TMR_CLEAR_ACA;
1816 			break;
1817 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1818 			tcm_function = TMR_CLEAR_TASK_SET;
1819 			break;
1820 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1821 			tcm_function = TMR_LUN_RESET;
1822 			break;
1823 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1824 			tcm_function = TMR_TARGET_WARM_RESET;
1825 			break;
1826 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1827 			tcm_function = TMR_TARGET_COLD_RESET;
1828 			break;
1829 		default:
1830 			pr_err("Unknown iSCSI TMR Function:"
1831 			       " 0x%02x\n", function);
1832 			return iscsit_add_reject_cmd(cmd,
1833 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1834 		}
1835 
1836 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1837 					 tcm_function, GFP_KERNEL);
1838 		if (ret < 0)
1839 			return iscsit_add_reject_cmd(cmd,
1840 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1841 
1842 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1843 	}
1844 
1845 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1846 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1847 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1848 	cmd->init_task_tag	= hdr->itt;
1849 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1850 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1851 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1852 	se_tmr			= cmd->se_cmd.se_tmr_req;
1853 	tmr_req			= cmd->tmr_req;
1854 	/*
1855 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1856 	 */
1857 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1858 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1859 					       scsilun_to_int(&hdr->lun));
1860 		if (ret < 0) {
1861 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1862 			goto attach;
1863 		}
1864 	}
1865 
1866 	switch (function) {
1867 	case ISCSI_TM_FUNC_ABORT_TASK:
1868 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1869 		if (se_tmr->response)
1870 			goto attach;
1871 		break;
1872 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1873 	case ISCSI_TM_FUNC_CLEAR_ACA:
1874 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1875 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1876 		break;
1877 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1878 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1879 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1880 			goto attach;
1881 		}
1882 		break;
1883 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1884 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1885 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1886 			goto attach;
1887 		}
1888 		break;
1889 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1890 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1891 		/*
1892 		 * Perform sanity checks on the ExpDataSN only if the
1893 		 * TASK_REASSIGN was successful.
1894 		 */
1895 		if (se_tmr->response)
1896 			break;
1897 
1898 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1899 			return iscsit_add_reject_cmd(cmd,
1900 					ISCSI_REASON_BOOKMARK_INVALID, buf);
1901 		break;
1902 	default:
1903 		pr_err("Unknown TMR function: 0x%02x, protocol"
1904 			" error.\n", function);
1905 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1906 		goto attach;
1907 	}
1908 
1909 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1910 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1911 		se_tmr->call_transport = 1;
1912 attach:
1913 	spin_lock_bh(&conn->cmd_lock);
1914 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1915 	spin_unlock_bh(&conn->cmd_lock);
1916 
1917 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1918 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1919 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1920 			out_of_order_cmdsn = 1;
1921 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1922 			return 0;
1923 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1924 			return -1;
1925 	}
1926 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1927 
1928 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1929 		return 0;
1930 	/*
1931 	 * Found the referenced task, send to transport for processing.
1932 	 */
1933 	if (se_tmr->call_transport)
1934 		return transport_generic_handle_tmr(&cmd->se_cmd);
1935 
1936 	/*
1937 	 * Could not find the referenced LUN, task, or Task Management
1938 	 * command not authorized or supported.  Change state and
1939 	 * let the tx_thread send the response.
1940 	 *
1941 	 * For connection recovery, this is also the default action for
1942 	 * TMR TASK_REASSIGN.
1943 	 */
1944 	if (sess_ref) {
1945 		pr_debug("Handle TMR, using sess_ref=true check\n");
1946 		target_put_sess_cmd(&cmd->se_cmd);
1947 	}
1948 
1949 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1950 	return 0;
1951 }
1952 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
1953 
1954 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1955 int
1956 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1957 		      struct iscsi_text *hdr)
1958 {
1959 	u32 payload_length = ntoh24(hdr->dlength);
1960 
1961 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1962 		pr_err("Unable to accept text parameter length: %u"
1963 			"greater than MaxXmitDataSegmentLength %u.\n",
1964 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1965 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1966 					 (unsigned char *)hdr);
1967 	}
1968 
1969 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
1970 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
1971 		pr_err("Multi sequence text commands currently not supported\n");
1972 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
1973 					(unsigned char *)hdr);
1974 	}
1975 
1976 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1977 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1978 		hdr->exp_statsn, payload_length);
1979 
1980 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1981 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1982 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1983 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
1984 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1985 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1986 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1987 	cmd->data_direction	= DMA_NONE;
1988 	cmd->text_in_ptr	= NULL;
1989 
1990 	return 0;
1991 }
1992 EXPORT_SYMBOL(iscsit_setup_text_cmd);
1993 
1994 int
1995 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1996 			struct iscsi_text *hdr)
1997 {
1998 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
1999 	int cmdsn_ret;
2000 
2001 	if (!text_in) {
2002 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2003 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2004 			pr_err("Unable to locate text_in buffer for sendtargets"
2005 			       " discovery\n");
2006 			goto reject;
2007 		}
2008 		goto empty_sendtargets;
2009 	}
2010 	if (strncmp("SendTargets", text_in, 11) != 0) {
2011 		pr_err("Received Text Data that is not"
2012 			" SendTargets, cannot continue.\n");
2013 		goto reject;
2014 	}
2015 	text_ptr = strchr(text_in, '=');
2016 	if (!text_ptr) {
2017 		pr_err("No \"=\" separator found in Text Data,"
2018 			"  cannot continue.\n");
2019 		goto reject;
2020 	}
2021 	if (!strncmp("=All", text_ptr, 4)) {
2022 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2023 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2024 		   !strncmp("=eui.", text_ptr, 5)) {
2025 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2026 	} else {
2027 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2028 		goto reject;
2029 	}
2030 
2031 	spin_lock_bh(&conn->cmd_lock);
2032 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2033 	spin_unlock_bh(&conn->cmd_lock);
2034 
2035 empty_sendtargets:
2036 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2037 
2038 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2039 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2040 				(unsigned char *)hdr, hdr->cmdsn);
2041 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2042 			return -1;
2043 
2044 		return 0;
2045 	}
2046 
2047 	return iscsit_execute_cmd(cmd, 0);
2048 
2049 reject:
2050 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2051 				 (unsigned char *)hdr);
2052 }
2053 EXPORT_SYMBOL(iscsit_process_text_cmd);
2054 
2055 static int
2056 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2057 		       unsigned char *buf)
2058 {
2059 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2060 	char *text_in = NULL;
2061 	u32 payload_length = ntoh24(hdr->dlength);
2062 	int rx_size, rc;
2063 
2064 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2065 	if (rc < 0)
2066 		return 0;
2067 
2068 	rx_size = payload_length;
2069 	if (payload_length) {
2070 		u32 checksum = 0, data_crc = 0;
2071 		u32 padding = 0, pad_bytes = 0;
2072 		int niov = 0, rx_got;
2073 		struct kvec iov[3];
2074 
2075 		text_in = kzalloc(payload_length, GFP_KERNEL);
2076 		if (!text_in) {
2077 			pr_err("Unable to allocate memory for"
2078 				" incoming text parameters\n");
2079 			goto reject;
2080 		}
2081 		cmd->text_in_ptr = text_in;
2082 
2083 		memset(iov, 0, 3 * sizeof(struct kvec));
2084 		iov[niov].iov_base	= text_in;
2085 		iov[niov++].iov_len	= payload_length;
2086 
2087 		padding = ((-payload_length) & 3);
2088 		if (padding != 0) {
2089 			iov[niov].iov_base = &pad_bytes;
2090 			iov[niov++].iov_len  = padding;
2091 			rx_size += padding;
2092 			pr_debug("Receiving %u additional bytes"
2093 					" for padding.\n", padding);
2094 		}
2095 		if (conn->conn_ops->DataDigest) {
2096 			iov[niov].iov_base	= &checksum;
2097 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2098 			rx_size += ISCSI_CRC_LEN;
2099 		}
2100 
2101 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2102 		if (rx_got != rx_size)
2103 			goto reject;
2104 
2105 		if (conn->conn_ops->DataDigest) {
2106 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2107 					text_in, payload_length,
2108 					padding, (u8 *)&pad_bytes,
2109 					(u8 *)&data_crc);
2110 
2111 			if (checksum != data_crc) {
2112 				pr_err("Text data CRC32C DataDigest"
2113 					" 0x%08x does not match computed"
2114 					" 0x%08x\n", checksum, data_crc);
2115 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2116 					pr_err("Unable to recover from"
2117 					" Text Data digest failure while in"
2118 						" ERL=0.\n");
2119 					goto reject;
2120 				} else {
2121 					/*
2122 					 * Silently drop this PDU and let the
2123 					 * initiator plug the CmdSN gap.
2124 					 */
2125 					pr_debug("Dropping Text"
2126 					" Command CmdSN: 0x%08x due to"
2127 					" DataCRC error.\n", hdr->cmdsn);
2128 					kfree(text_in);
2129 					return 0;
2130 				}
2131 			} else {
2132 				pr_debug("Got CRC32C DataDigest"
2133 					" 0x%08x for %u bytes of text data.\n",
2134 						checksum, payload_length);
2135 			}
2136 		}
2137 		text_in[payload_length - 1] = '\0';
2138 		pr_debug("Successfully read %d bytes of text"
2139 				" data.\n", payload_length);
2140 	}
2141 
2142 	return iscsit_process_text_cmd(conn, cmd, hdr);
2143 
2144 reject:
2145 	kfree(cmd->text_in_ptr);
2146 	cmd->text_in_ptr = NULL;
2147 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2148 }
2149 
2150 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2151 {
2152 	struct iscsi_conn *conn_p;
2153 	struct iscsi_session *sess = conn->sess;
2154 
2155 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2156 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2157 
2158 	atomic_set(&sess->session_logout, 1);
2159 	atomic_set(&conn->conn_logout_remove, 1);
2160 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2161 
2162 	iscsit_inc_conn_usage_count(conn);
2163 	iscsit_inc_session_usage_count(sess);
2164 
2165 	spin_lock_bh(&sess->conn_lock);
2166 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2167 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2168 			continue;
2169 
2170 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2171 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2172 	}
2173 	spin_unlock_bh(&sess->conn_lock);
2174 
2175 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2176 
2177 	return 0;
2178 }
2179 
2180 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2181 {
2182 	struct iscsi_conn *l_conn;
2183 	struct iscsi_session *sess = conn->sess;
2184 
2185 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2186 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2187 
2188 	/*
2189 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2190 	 * can arrive on a connection with a differing CID.
2191 	 */
2192 	if (conn->cid == cmd->logout_cid) {
2193 		spin_lock_bh(&conn->state_lock);
2194 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2195 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2196 
2197 		atomic_set(&conn->conn_logout_remove, 1);
2198 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2199 		iscsit_inc_conn_usage_count(conn);
2200 
2201 		spin_unlock_bh(&conn->state_lock);
2202 	} else {
2203 		/*
2204 		 * Handle all different cid CLOSECONNECTION requests in
2205 		 * iscsit_logout_post_handler_diffcid() as to give enough
2206 		 * time for any non immediate command's CmdSN to be
2207 		 * acknowledged on the connection in question.
2208 		 *
2209 		 * Here we simply make sure the CID is still around.
2210 		 */
2211 		l_conn = iscsit_get_conn_from_cid(sess,
2212 				cmd->logout_cid);
2213 		if (!l_conn) {
2214 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2215 			iscsit_add_cmd_to_response_queue(cmd, conn,
2216 					cmd->i_state);
2217 			return 0;
2218 		}
2219 
2220 		iscsit_dec_conn_usage_count(l_conn);
2221 	}
2222 
2223 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2224 
2225 	return 0;
2226 }
2227 
2228 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2229 {
2230 	struct iscsi_session *sess = conn->sess;
2231 
2232 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2233 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2234 
2235 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2236 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2237 			" while ERL!=2.\n");
2238 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2239 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2240 		return 0;
2241 	}
2242 
2243 	if (conn->cid == cmd->logout_cid) {
2244 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2245 			" with CID: %hu on CID: %hu, implementation error.\n",
2246 				cmd->logout_cid, conn->cid);
2247 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2248 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2249 		return 0;
2250 	}
2251 
2252 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2253 
2254 	return 0;
2255 }
2256 
2257 int
2258 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2259 			unsigned char *buf)
2260 {
2261 	int cmdsn_ret, logout_remove = 0;
2262 	u8 reason_code = 0;
2263 	struct iscsi_logout *hdr;
2264 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2265 
2266 	hdr			= (struct iscsi_logout *) buf;
2267 	reason_code		= (hdr->flags & 0x7f);
2268 
2269 	if (tiqn) {
2270 		spin_lock(&tiqn->logout_stats.lock);
2271 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2272 			tiqn->logout_stats.normal_logouts++;
2273 		else
2274 			tiqn->logout_stats.abnormal_logouts++;
2275 		spin_unlock(&tiqn->logout_stats.lock);
2276 	}
2277 
2278 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2279 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2280 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2281 		hdr->cid, conn->cid);
2282 
2283 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2284 		pr_err("Received logout request on connection that"
2285 			" is not in logged in state, ignoring request.\n");
2286 		iscsit_free_cmd(cmd, false);
2287 		return 0;
2288 	}
2289 
2290 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2291 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2292 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2293 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2294 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2295 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2296 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2297 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2298 	cmd->logout_reason      = reason_code;
2299 	cmd->data_direction     = DMA_NONE;
2300 
2301 	/*
2302 	 * We need to sleep in these cases (by returning 1) until the Logout
2303 	 * Response gets sent in the tx thread.
2304 	 */
2305 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2306 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2307 	    be16_to_cpu(hdr->cid) == conn->cid))
2308 		logout_remove = 1;
2309 
2310 	spin_lock_bh(&conn->cmd_lock);
2311 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2312 	spin_unlock_bh(&conn->cmd_lock);
2313 
2314 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2315 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2316 
2317 	/*
2318 	 * Immediate commands are executed, well, immediately.
2319 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2320 	 */
2321 	if (cmd->immediate_cmd) {
2322 		int ret = iscsit_execute_cmd(cmd, 0);
2323 
2324 		if (ret < 0)
2325 			return ret;
2326 	} else {
2327 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2328 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2329 			logout_remove = 0;
2330 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2331 			return -1;
2332 	}
2333 
2334 	return logout_remove;
2335 }
2336 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2337 
2338 static int iscsit_handle_snack(
2339 	struct iscsi_conn *conn,
2340 	unsigned char *buf)
2341 {
2342 	struct iscsi_snack *hdr;
2343 
2344 	hdr			= (struct iscsi_snack *) buf;
2345 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2346 
2347 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2348 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2349 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2350 			hdr->begrun, hdr->runlength, conn->cid);
2351 
2352 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2353 		pr_err("Initiator sent SNACK request while in"
2354 			" ErrorRecoveryLevel=0.\n");
2355 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2356 					 buf);
2357 	}
2358 	/*
2359 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2360 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2361 	 */
2362 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2363 	case 0:
2364 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2365 			hdr->itt,
2366 			be32_to_cpu(hdr->ttt),
2367 			be32_to_cpu(hdr->begrun),
2368 			be32_to_cpu(hdr->runlength));
2369 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2370 		return iscsit_handle_status_snack(conn, hdr->itt,
2371 			be32_to_cpu(hdr->ttt),
2372 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2373 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2374 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2375 			be32_to_cpu(hdr->begrun),
2376 			be32_to_cpu(hdr->runlength));
2377 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2378 		/* FIXME: Support R-Data SNACK */
2379 		pr_err("R-Data SNACK Not Supported.\n");
2380 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2381 					 buf);
2382 	default:
2383 		pr_err("Unknown SNACK type 0x%02x, protocol"
2384 			" error.\n", hdr->flags & 0x0f);
2385 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2386 					 buf);
2387 	}
2388 
2389 	return 0;
2390 }
2391 
2392 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2393 {
2394 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2395 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2396 		wait_for_completion_interruptible_timeout(
2397 					&conn->rx_half_close_comp,
2398 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2399 	}
2400 }
2401 
2402 static int iscsit_handle_immediate_data(
2403 	struct iscsi_cmd *cmd,
2404 	struct iscsi_scsi_req *hdr,
2405 	u32 length)
2406 {
2407 	int iov_ret, rx_got = 0, rx_size = 0;
2408 	u32 checksum, iov_count = 0, padding = 0;
2409 	struct iscsi_conn *conn = cmd->conn;
2410 	struct kvec *iov;
2411 
2412 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2413 	if (iov_ret < 0)
2414 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2415 
2416 	rx_size = length;
2417 	iov_count = iov_ret;
2418 	iov = &cmd->iov_data[0];
2419 
2420 	padding = ((-length) & 3);
2421 	if (padding != 0) {
2422 		iov[iov_count].iov_base	= cmd->pad_bytes;
2423 		iov[iov_count++].iov_len = padding;
2424 		rx_size += padding;
2425 	}
2426 
2427 	if (conn->conn_ops->DataDigest) {
2428 		iov[iov_count].iov_base		= &checksum;
2429 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2430 		rx_size += ISCSI_CRC_LEN;
2431 	}
2432 
2433 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2434 
2435 	iscsit_unmap_iovec(cmd);
2436 
2437 	if (rx_got != rx_size) {
2438 		iscsit_rx_thread_wait_for_tcp(conn);
2439 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2440 	}
2441 
2442 	if (conn->conn_ops->DataDigest) {
2443 		u32 data_crc;
2444 
2445 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2446 						    cmd->write_data_done, length, padding,
2447 						    cmd->pad_bytes);
2448 
2449 		if (checksum != data_crc) {
2450 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2451 				" does not match computed 0x%08x\n", checksum,
2452 				data_crc);
2453 
2454 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2455 				pr_err("Unable to recover from"
2456 					" Immediate Data digest failure while"
2457 					" in ERL=0.\n");
2458 				iscsit_reject_cmd(cmd,
2459 						ISCSI_REASON_DATA_DIGEST_ERROR,
2460 						(unsigned char *)hdr);
2461 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2462 			} else {
2463 				iscsit_reject_cmd(cmd,
2464 						ISCSI_REASON_DATA_DIGEST_ERROR,
2465 						(unsigned char *)hdr);
2466 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2467 			}
2468 		} else {
2469 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2470 				" %u bytes of Immediate Data\n", checksum,
2471 				length);
2472 		}
2473 	}
2474 
2475 	cmd->write_data_done += length;
2476 
2477 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2478 		spin_lock_bh(&cmd->istate_lock);
2479 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2480 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2481 		spin_unlock_bh(&cmd->istate_lock);
2482 	}
2483 
2484 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2485 }
2486 
2487 /*
2488  *	Called with sess->conn_lock held.
2489  */
2490 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2491 	with active network interface */
2492 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2493 {
2494 	struct iscsi_cmd *cmd;
2495 	struct iscsi_conn *conn_p;
2496 	bool found = false;
2497 
2498 	/*
2499 	 * Only send a Asynchronous Message on connections whos network
2500 	 * interface is still functional.
2501 	 */
2502 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2503 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2504 			iscsit_inc_conn_usage_count(conn_p);
2505 			found = true;
2506 			break;
2507 		}
2508 	}
2509 
2510 	if (!found)
2511 		return;
2512 
2513 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2514 	if (!cmd) {
2515 		iscsit_dec_conn_usage_count(conn_p);
2516 		return;
2517 	}
2518 
2519 	cmd->logout_cid = conn->cid;
2520 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2521 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2522 
2523 	spin_lock_bh(&conn_p->cmd_lock);
2524 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2525 	spin_unlock_bh(&conn_p->cmd_lock);
2526 
2527 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2528 	iscsit_dec_conn_usage_count(conn_p);
2529 }
2530 
2531 static int iscsit_send_conn_drop_async_message(
2532 	struct iscsi_cmd *cmd,
2533 	struct iscsi_conn *conn)
2534 {
2535 	struct iscsi_async *hdr;
2536 
2537 	cmd->tx_size = ISCSI_HDR_LEN;
2538 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2539 
2540 	hdr			= (struct iscsi_async *) cmd->pdu;
2541 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2542 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2543 	cmd->init_task_tag	= RESERVED_ITT;
2544 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2545 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2546 	cmd->stat_sn		= conn->stat_sn++;
2547 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2548 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2549 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2550 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2551 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2552 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2553 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2554 
2555 	if (conn->conn_ops->HeaderDigest) {
2556 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2557 
2558 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
2559 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2560 
2561 		cmd->tx_size += ISCSI_CRC_LEN;
2562 		pr_debug("Attaching CRC32C HeaderDigest to"
2563 			" Async Message 0x%08x\n", *header_digest);
2564 	}
2565 
2566 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2567 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2568 	cmd->iov_misc_count		= 1;
2569 
2570 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2571 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2572 			cmd->logout_cid, conn->cid);
2573 	return 0;
2574 }
2575 
2576 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2577 {
2578 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2579 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2580 		wait_for_completion_interruptible_timeout(
2581 					&conn->tx_half_close_comp,
2582 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2583 	}
2584 }
2585 
2586 static void
2587 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2588 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2589 			bool set_statsn)
2590 {
2591 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2592 	hdr->flags		= datain->flags;
2593 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2594 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2595 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2596 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2597 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2598 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2599 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2600 		}
2601 	}
2602 	hton24(hdr->dlength, datain->length);
2603 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2604 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2605 				(struct scsi_lun *)&hdr->lun);
2606 	else
2607 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2608 
2609 	hdr->itt		= cmd->init_task_tag;
2610 
2611 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2612 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2613 	else
2614 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2615 	if (set_statsn)
2616 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2617 	else
2618 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2619 
2620 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2621 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2622 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2623 	hdr->offset		= cpu_to_be32(datain->offset);
2624 
2625 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2626 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2627 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2628 		ntohl(hdr->offset), datain->length, conn->cid);
2629 }
2630 
2631 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2632 {
2633 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2634 	struct iscsi_datain datain;
2635 	struct iscsi_datain_req *dr;
2636 	struct kvec *iov;
2637 	u32 iov_count = 0, tx_size = 0;
2638 	int eodr = 0, ret, iov_ret;
2639 	bool set_statsn = false;
2640 
2641 	memset(&datain, 0, sizeof(struct iscsi_datain));
2642 	dr = iscsit_get_datain_values(cmd, &datain);
2643 	if (!dr) {
2644 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2645 				cmd->init_task_tag);
2646 		return -1;
2647 	}
2648 	/*
2649 	 * Be paranoid and double check the logic for now.
2650 	 */
2651 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2652 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2653 			" datain.length: %u exceeds cmd->data_length: %u\n",
2654 			cmd->init_task_tag, datain.offset, datain.length,
2655 			cmd->se_cmd.data_length);
2656 		return -1;
2657 	}
2658 
2659 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2660 	/*
2661 	 * Special case for successfully execution w/ both DATAIN
2662 	 * and Sense Data.
2663 	 */
2664 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2665 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2666 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2667 	else {
2668 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2669 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2670 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2671 			cmd->stat_sn = conn->stat_sn++;
2672 			set_statsn = true;
2673 		} else if (dr->dr_complete ==
2674 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2675 			set_statsn = true;
2676 	}
2677 
2678 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2679 
2680 	iov = &cmd->iov_data[0];
2681 	iov[iov_count].iov_base	= cmd->pdu;
2682 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2683 	tx_size += ISCSI_HDR_LEN;
2684 
2685 	if (conn->conn_ops->HeaderDigest) {
2686 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2687 
2688 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
2689 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2690 
2691 		iov[0].iov_len += ISCSI_CRC_LEN;
2692 		tx_size += ISCSI_CRC_LEN;
2693 
2694 		pr_debug("Attaching CRC32 HeaderDigest"
2695 			" for DataIN PDU 0x%08x\n", *header_digest);
2696 	}
2697 
2698 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
2699 				datain.offset, datain.length);
2700 	if (iov_ret < 0)
2701 		return -1;
2702 
2703 	iov_count += iov_ret;
2704 	tx_size += datain.length;
2705 
2706 	cmd->padding = ((-datain.length) & 3);
2707 	if (cmd->padding) {
2708 		iov[iov_count].iov_base		= cmd->pad_bytes;
2709 		iov[iov_count++].iov_len	= cmd->padding;
2710 		tx_size += cmd->padding;
2711 
2712 		pr_debug("Attaching %u padding bytes\n",
2713 				cmd->padding);
2714 	}
2715 	if (conn->conn_ops->DataDigest) {
2716 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash, cmd,
2717 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2718 
2719 		iov[iov_count].iov_base	= &cmd->data_crc;
2720 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2721 		tx_size += ISCSI_CRC_LEN;
2722 
2723 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2724 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2725 	}
2726 
2727 	cmd->iov_data_count = iov_count;
2728 	cmd->tx_size = tx_size;
2729 
2730 	ret = iscsit_fe_sendpage_sg(cmd, conn);
2731 
2732 	iscsit_unmap_iovec(cmd);
2733 
2734 	if (ret < 0) {
2735 		iscsit_tx_thread_wait_for_tcp(conn);
2736 		return ret;
2737 	}
2738 
2739 	if (dr->dr_complete) {
2740 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2741 				2 : 1;
2742 		iscsit_free_datain_req(cmd, dr);
2743 	}
2744 
2745 	return eodr;
2746 }
2747 
2748 int
2749 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2750 			struct iscsi_logout_rsp *hdr)
2751 {
2752 	struct iscsi_conn *logout_conn = NULL;
2753 	struct iscsi_conn_recovery *cr = NULL;
2754 	struct iscsi_session *sess = conn->sess;
2755 	/*
2756 	 * The actual shutting down of Sessions and/or Connections
2757 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2758 	 * is done in scsi_logout_post_handler().
2759 	 */
2760 	switch (cmd->logout_reason) {
2761 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2762 		pr_debug("iSCSI session logout successful, setting"
2763 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2764 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2765 		break;
2766 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2767 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2768 			break;
2769 		/*
2770 		 * For CLOSECONNECTION logout requests carrying
2771 		 * a matching logout CID -> local CID, the reference
2772 		 * for the local CID will have been incremented in
2773 		 * iscsi_logout_closeconnection().
2774 		 *
2775 		 * For CLOSECONNECTION logout requests carrying
2776 		 * a different CID than the connection it arrived
2777 		 * on, the connection responding to cmd->logout_cid
2778 		 * is stopped in iscsit_logout_post_handler_diffcid().
2779 		 */
2780 
2781 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2782 			" successful.\n", cmd->logout_cid, conn->cid);
2783 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2784 		break;
2785 	case ISCSI_LOGOUT_REASON_RECOVERY:
2786 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2787 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2788 			break;
2789 		/*
2790 		 * If the connection is still active from our point of view
2791 		 * force connection recovery to occur.
2792 		 */
2793 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2794 				cmd->logout_cid);
2795 		if (logout_conn) {
2796 			iscsit_connection_reinstatement_rcfr(logout_conn);
2797 			iscsit_dec_conn_usage_count(logout_conn);
2798 		}
2799 
2800 		cr = iscsit_get_inactive_connection_recovery_entry(
2801 				conn->sess, cmd->logout_cid);
2802 		if (!cr) {
2803 			pr_err("Unable to locate CID: %hu for"
2804 			" REMOVECONNFORRECOVERY Logout Request.\n",
2805 				cmd->logout_cid);
2806 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2807 			break;
2808 		}
2809 
2810 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2811 
2812 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2813 			" for recovery for CID: %hu on CID: %hu successful.\n",
2814 				cmd->logout_cid, conn->cid);
2815 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2816 		break;
2817 	default:
2818 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2819 				cmd->logout_reason);
2820 		return -1;
2821 	}
2822 
2823 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2824 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2825 	hdr->response		= cmd->logout_response;
2826 	hdr->itt		= cmd->init_task_tag;
2827 	cmd->stat_sn		= conn->stat_sn++;
2828 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2829 
2830 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2831 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2832 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2833 
2834 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2835 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2836 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2837 		cmd->logout_cid, conn->cid);
2838 
2839 	return 0;
2840 }
2841 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2842 
2843 static int
2844 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2845 {
2846 	struct kvec *iov;
2847 	int niov = 0, tx_size, rc;
2848 
2849 	rc = iscsit_build_logout_rsp(cmd, conn,
2850 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2851 	if (rc < 0)
2852 		return rc;
2853 
2854 	tx_size = ISCSI_HDR_LEN;
2855 	iov = &cmd->iov_misc[0];
2856 	iov[niov].iov_base	= cmd->pdu;
2857 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2858 
2859 	if (conn->conn_ops->HeaderDigest) {
2860 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2861 
2862 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, &cmd->pdu[0],
2863 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2864 
2865 		iov[0].iov_len += ISCSI_CRC_LEN;
2866 		tx_size += ISCSI_CRC_LEN;
2867 		pr_debug("Attaching CRC32C HeaderDigest to"
2868 			" Logout Response 0x%08x\n", *header_digest);
2869 	}
2870 	cmd->iov_misc_count = niov;
2871 	cmd->tx_size = tx_size;
2872 
2873 	return 0;
2874 }
2875 
2876 void
2877 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2878 		       struct iscsi_nopin *hdr, bool nopout_response)
2879 {
2880 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2881 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2882         hton24(hdr->dlength, cmd->buf_ptr_size);
2883 	if (nopout_response)
2884 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2885 	hdr->itt		= cmd->init_task_tag;
2886 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2887 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2888 				  conn->stat_sn;
2889 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2890 
2891 	if (nopout_response)
2892 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2893 
2894 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2895 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2896 
2897 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2898 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2899 		"Solicitied" : "Unsolicitied", cmd->init_task_tag,
2900 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2901 }
2902 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2903 
2904 /*
2905  *	Unsolicited NOPIN, either requesting a response or not.
2906  */
2907 static int iscsit_send_unsolicited_nopin(
2908 	struct iscsi_cmd *cmd,
2909 	struct iscsi_conn *conn,
2910 	int want_response)
2911 {
2912 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2913 	int tx_size = ISCSI_HDR_LEN, ret;
2914 
2915 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
2916 
2917 	if (conn->conn_ops->HeaderDigest) {
2918 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2919 
2920 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
2921 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2922 
2923 		tx_size += ISCSI_CRC_LEN;
2924 		pr_debug("Attaching CRC32C HeaderDigest to"
2925 			" NopIN 0x%08x\n", *header_digest);
2926 	}
2927 
2928 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2929 	cmd->iov_misc[0].iov_len	= tx_size;
2930 	cmd->iov_misc_count	= 1;
2931 	cmd->tx_size		= tx_size;
2932 
2933 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2934 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2935 
2936 	ret = iscsit_send_tx_data(cmd, conn, 1);
2937 	if (ret < 0) {
2938 		iscsit_tx_thread_wait_for_tcp(conn);
2939 		return ret;
2940 	}
2941 
2942 	spin_lock_bh(&cmd->istate_lock);
2943 	cmd->i_state = want_response ?
2944 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2945 	spin_unlock_bh(&cmd->istate_lock);
2946 
2947 	return 0;
2948 }
2949 
2950 static int
2951 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2952 {
2953 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2954 	struct kvec *iov;
2955 	u32 padding = 0;
2956 	int niov = 0, tx_size;
2957 
2958 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
2959 
2960 	tx_size = ISCSI_HDR_LEN;
2961 	iov = &cmd->iov_misc[0];
2962 	iov[niov].iov_base	= cmd->pdu;
2963 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2964 
2965 	if (conn->conn_ops->HeaderDigest) {
2966 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2967 
2968 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
2969 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2970 
2971 		iov[0].iov_len += ISCSI_CRC_LEN;
2972 		tx_size += ISCSI_CRC_LEN;
2973 		pr_debug("Attaching CRC32C HeaderDigest"
2974 			" to NopIn 0x%08x\n", *header_digest);
2975 	}
2976 
2977 	/*
2978 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2979 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2980 	 */
2981 	if (cmd->buf_ptr_size) {
2982 		iov[niov].iov_base	= cmd->buf_ptr;
2983 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2984 		tx_size += cmd->buf_ptr_size;
2985 
2986 		pr_debug("Echoing back %u bytes of ping"
2987 			" data.\n", cmd->buf_ptr_size);
2988 
2989 		padding = ((-cmd->buf_ptr_size) & 3);
2990 		if (padding != 0) {
2991 			iov[niov].iov_base = &cmd->pad_bytes;
2992 			iov[niov++].iov_len = padding;
2993 			tx_size += padding;
2994 			pr_debug("Attaching %u additional"
2995 				" padding bytes.\n", padding);
2996 		}
2997 		if (conn->conn_ops->DataDigest) {
2998 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
2999 				cmd->buf_ptr, cmd->buf_ptr_size,
3000 				padding, (u8 *)&cmd->pad_bytes,
3001 				(u8 *)&cmd->data_crc);
3002 
3003 			iov[niov].iov_base = &cmd->data_crc;
3004 			iov[niov++].iov_len = ISCSI_CRC_LEN;
3005 			tx_size += ISCSI_CRC_LEN;
3006 			pr_debug("Attached DataDigest for %u"
3007 				" bytes of ping data, CRC 0x%08x\n",
3008 				cmd->buf_ptr_size, cmd->data_crc);
3009 		}
3010 	}
3011 
3012 	cmd->iov_misc_count = niov;
3013 	cmd->tx_size = tx_size;
3014 
3015 	return 0;
3016 }
3017 
3018 static int iscsit_send_r2t(
3019 	struct iscsi_cmd *cmd,
3020 	struct iscsi_conn *conn)
3021 {
3022 	int tx_size = 0;
3023 	struct iscsi_r2t *r2t;
3024 	struct iscsi_r2t_rsp *hdr;
3025 	int ret;
3026 
3027 	r2t = iscsit_get_r2t_from_list(cmd);
3028 	if (!r2t)
3029 		return -1;
3030 
3031 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3032 	memset(hdr, 0, ISCSI_HDR_LEN);
3033 	hdr->opcode		= ISCSI_OP_R2T;
3034 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3035 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3036 			(struct scsi_lun *)&hdr->lun);
3037 	hdr->itt		= cmd->init_task_tag;
3038 	r2t->targ_xfer_tag	= session_get_next_ttt(conn->sess);
3039 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3040 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3041 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3042 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3043 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3044 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3045 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3046 
3047 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3048 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3049 	tx_size += ISCSI_HDR_LEN;
3050 
3051 	if (conn->conn_ops->HeaderDigest) {
3052 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3053 
3054 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
3055 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3056 
3057 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3058 		tx_size += ISCSI_CRC_LEN;
3059 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
3060 			" PDU 0x%08x\n", *header_digest);
3061 	}
3062 
3063 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3064 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3065 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3066 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3067 			r2t->offset, r2t->xfer_len, conn->cid);
3068 
3069 	cmd->iov_misc_count = 1;
3070 	cmd->tx_size = tx_size;
3071 
3072 	spin_lock_bh(&cmd->r2t_lock);
3073 	r2t->sent_r2t = 1;
3074 	spin_unlock_bh(&cmd->r2t_lock);
3075 
3076 	ret = iscsit_send_tx_data(cmd, conn, 1);
3077 	if (ret < 0) {
3078 		iscsit_tx_thread_wait_for_tcp(conn);
3079 		return ret;
3080 	}
3081 
3082 	spin_lock_bh(&cmd->dataout_timeout_lock);
3083 	iscsit_start_dataout_timer(cmd, conn);
3084 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3085 
3086 	return 0;
3087 }
3088 
3089 /*
3090  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3091  *		connection recovery.
3092  */
3093 int iscsit_build_r2ts_for_cmd(
3094 	struct iscsi_conn *conn,
3095 	struct iscsi_cmd *cmd,
3096 	bool recovery)
3097 {
3098 	int first_r2t = 1;
3099 	u32 offset = 0, xfer_len = 0;
3100 
3101 	spin_lock_bh(&cmd->r2t_lock);
3102 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3103 		spin_unlock_bh(&cmd->r2t_lock);
3104 		return 0;
3105 	}
3106 
3107 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3108 	    !recovery)
3109 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3110 
3111 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3112 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3113 			offset = cmd->r2t_offset;
3114 
3115 			if (first_r2t && recovery) {
3116 				int new_data_end = offset +
3117 					conn->sess->sess_ops->MaxBurstLength -
3118 					cmd->next_burst_len;
3119 
3120 				if (new_data_end > cmd->se_cmd.data_length)
3121 					xfer_len = cmd->se_cmd.data_length - offset;
3122 				else
3123 					xfer_len =
3124 						conn->sess->sess_ops->MaxBurstLength -
3125 						cmd->next_burst_len;
3126 			} else {
3127 				int new_data_end = offset +
3128 					conn->sess->sess_ops->MaxBurstLength;
3129 
3130 				if (new_data_end > cmd->se_cmd.data_length)
3131 					xfer_len = cmd->se_cmd.data_length - offset;
3132 				else
3133 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3134 			}
3135 			cmd->r2t_offset += xfer_len;
3136 
3137 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3138 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3139 		} else {
3140 			struct iscsi_seq *seq;
3141 
3142 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3143 			if (!seq) {
3144 				spin_unlock_bh(&cmd->r2t_lock);
3145 				return -1;
3146 			}
3147 
3148 			offset = seq->offset;
3149 			xfer_len = seq->xfer_len;
3150 
3151 			if (cmd->seq_send_order == cmd->seq_count)
3152 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3153 		}
3154 		cmd->outstanding_r2ts++;
3155 		first_r2t = 0;
3156 
3157 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3158 			spin_unlock_bh(&cmd->r2t_lock);
3159 			return -1;
3160 		}
3161 
3162 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3163 			break;
3164 	}
3165 	spin_unlock_bh(&cmd->r2t_lock);
3166 
3167 	return 0;
3168 }
3169 
3170 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3171 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3172 {
3173 	if (inc_stat_sn)
3174 		cmd->stat_sn = conn->stat_sn++;
3175 
3176 	atomic_long_inc(&conn->sess->rsp_pdus);
3177 
3178 	memset(hdr, 0, ISCSI_HDR_LEN);
3179 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3180 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3181 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3182 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3183 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3184 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3185 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3186 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3187 	}
3188 	hdr->response		= cmd->iscsi_response;
3189 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3190 	hdr->itt		= cmd->init_task_tag;
3191 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3192 
3193 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3194 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3195 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3196 
3197 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3198 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3199 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3200 		cmd->se_cmd.scsi_status, conn->cid);
3201 }
3202 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3203 
3204 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3205 {
3206 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3207 	struct kvec *iov;
3208 	u32 padding = 0, tx_size = 0;
3209 	int iov_count = 0;
3210 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3211 
3212 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3213 
3214 	iov = &cmd->iov_misc[0];
3215 	iov[iov_count].iov_base	= cmd->pdu;
3216 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3217 	tx_size += ISCSI_HDR_LEN;
3218 
3219 	/*
3220 	 * Attach SENSE DATA payload to iSCSI Response PDU
3221 	 */
3222 	if (cmd->se_cmd.sense_buffer &&
3223 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3224 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3225 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3226 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3227 
3228 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3229 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3230 		iov[iov_count].iov_base	= cmd->sense_buffer;
3231 		iov[iov_count++].iov_len =
3232 				(cmd->se_cmd.scsi_sense_length + padding);
3233 		tx_size += cmd->se_cmd.scsi_sense_length;
3234 
3235 		if (padding) {
3236 			memset(cmd->sense_buffer +
3237 				cmd->se_cmd.scsi_sense_length, 0, padding);
3238 			tx_size += padding;
3239 			pr_debug("Adding %u bytes of padding to"
3240 				" SENSE.\n", padding);
3241 		}
3242 
3243 		if (conn->conn_ops->DataDigest) {
3244 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
3245 				cmd->sense_buffer,
3246 				(cmd->se_cmd.scsi_sense_length + padding),
3247 				0, NULL, (u8 *)&cmd->data_crc);
3248 
3249 			iov[iov_count].iov_base    = &cmd->data_crc;
3250 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3251 			tx_size += ISCSI_CRC_LEN;
3252 
3253 			pr_debug("Attaching CRC32 DataDigest for"
3254 				" SENSE, %u bytes CRC 0x%08x\n",
3255 				(cmd->se_cmd.scsi_sense_length + padding),
3256 				cmd->data_crc);
3257 		}
3258 
3259 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3260 				" Response PDU\n",
3261 				cmd->se_cmd.scsi_sense_length);
3262 	}
3263 
3264 	if (conn->conn_ops->HeaderDigest) {
3265 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3266 
3267 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
3268 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3269 
3270 		iov[0].iov_len += ISCSI_CRC_LEN;
3271 		tx_size += ISCSI_CRC_LEN;
3272 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3273 				" PDU 0x%08x\n", *header_digest);
3274 	}
3275 
3276 	cmd->iov_misc_count = iov_count;
3277 	cmd->tx_size = tx_size;
3278 
3279 	return 0;
3280 }
3281 
3282 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3283 {
3284 	switch (se_tmr->response) {
3285 	case TMR_FUNCTION_COMPLETE:
3286 		return ISCSI_TMF_RSP_COMPLETE;
3287 	case TMR_TASK_DOES_NOT_EXIST:
3288 		return ISCSI_TMF_RSP_NO_TASK;
3289 	case TMR_LUN_DOES_NOT_EXIST:
3290 		return ISCSI_TMF_RSP_NO_LUN;
3291 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3292 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3293 	case TMR_FUNCTION_REJECTED:
3294 	default:
3295 		return ISCSI_TMF_RSP_REJECTED;
3296 	}
3297 }
3298 
3299 void
3300 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3301 			  struct iscsi_tm_rsp *hdr)
3302 {
3303 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3304 
3305 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3306 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3307 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3308 	hdr->itt		= cmd->init_task_tag;
3309 	cmd->stat_sn		= conn->stat_sn++;
3310 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3311 
3312 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3313 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3314 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3315 
3316 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3317 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3318 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3319 }
3320 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3321 
3322 static int
3323 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3324 {
3325 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3326 	u32 tx_size = 0;
3327 
3328 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3329 
3330 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3331 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3332 	tx_size += ISCSI_HDR_LEN;
3333 
3334 	if (conn->conn_ops->HeaderDigest) {
3335 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3336 
3337 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
3338 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3339 
3340 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3341 		tx_size += ISCSI_CRC_LEN;
3342 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3343 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3344 	}
3345 
3346 	cmd->iov_misc_count = 1;
3347 	cmd->tx_size = tx_size;
3348 
3349 	return 0;
3350 }
3351 
3352 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3353 {
3354 	bool ret = false;
3355 
3356 	if (np->np_sockaddr.ss_family == AF_INET6) {
3357 		const struct sockaddr_in6 sin6 = {
3358 			.sin6_addr = IN6ADDR_ANY_INIT };
3359 		struct sockaddr_in6 *sock_in6 =
3360 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3361 
3362 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3363 				sin6.sin6_addr.s6_addr, 16))
3364 			ret = true;
3365 	} else {
3366 		struct sockaddr_in * sock_in =
3367 			(struct sockaddr_in *)&np->np_sockaddr;
3368 
3369 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3370 			ret = true;
3371 	}
3372 
3373 	return ret;
3374 }
3375 
3376 #define SENDTARGETS_BUF_LIMIT 32768U
3377 
3378 static int
3379 iscsit_build_sendtargets_response(struct iscsi_cmd *cmd,
3380 				  enum iscsit_transport_type network_transport,
3381 				  int skip_bytes, bool *completed)
3382 {
3383 	char *payload = NULL;
3384 	struct iscsi_conn *conn = cmd->conn;
3385 	struct iscsi_portal_group *tpg;
3386 	struct iscsi_tiqn *tiqn;
3387 	struct iscsi_tpg_np *tpg_np;
3388 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3389 	int target_name_printed;
3390 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3391 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3392 	bool active;
3393 
3394 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3395 			 SENDTARGETS_BUF_LIMIT);
3396 
3397 	payload = kzalloc(buffer_len, GFP_KERNEL);
3398 	if (!payload) {
3399 		pr_err("Unable to allocate memory for sendtargets"
3400 				" response.\n");
3401 		return -ENOMEM;
3402 	}
3403 	/*
3404 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3405 	 * explicit case..
3406 	 */
3407 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3408 		text_ptr = strchr(text_in, '=');
3409 		if (!text_ptr) {
3410 			pr_err("Unable to locate '=' string in text_in:"
3411 			       " %s\n", text_in);
3412 			kfree(payload);
3413 			return -EINVAL;
3414 		}
3415 		/*
3416 		 * Skip over '=' character..
3417 		 */
3418 		text_ptr += 1;
3419 	}
3420 
3421 	spin_lock(&tiqn_lock);
3422 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3423 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3424 		     strcmp(tiqn->tiqn, text_ptr)) {
3425 			continue;
3426 		}
3427 
3428 		target_name_printed = 0;
3429 
3430 		spin_lock(&tiqn->tiqn_tpg_lock);
3431 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3432 
3433 			/* If demo_mode_discovery=0 and generate_node_acls=0
3434 			 * (demo mode dislabed) do not return
3435 			 * TargetName+TargetAddress unless a NodeACL exists.
3436 			 */
3437 
3438 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3439 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3440 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3441 				cmd->conn->sess->sess_ops->InitiatorName))) {
3442 				continue;
3443 			}
3444 
3445 			spin_lock(&tpg->tpg_state_lock);
3446 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3447 			spin_unlock(&tpg->tpg_state_lock);
3448 
3449 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3450 				continue;
3451 
3452 			spin_lock(&tpg->tpg_np_lock);
3453 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3454 						tpg_np_list) {
3455 				struct iscsi_np *np = tpg_np->tpg_np;
3456 				bool inaddr_any = iscsit_check_inaddr_any(np);
3457 				struct sockaddr_storage *sockaddr;
3458 
3459 				if (np->np_network_transport != network_transport)
3460 					continue;
3461 
3462 				if (!target_name_printed) {
3463 					len = sprintf(buf, "TargetName=%s",
3464 						      tiqn->tiqn);
3465 					len += 1;
3466 
3467 					if ((len + payload_len) > buffer_len) {
3468 						spin_unlock(&tpg->tpg_np_lock);
3469 						spin_unlock(&tiqn->tiqn_tpg_lock);
3470 						end_of_buf = 1;
3471 						goto eob;
3472 					}
3473 
3474 					if (skip_bytes && len <= skip_bytes) {
3475 						skip_bytes -= len;
3476 					} else {
3477 						memcpy(payload + payload_len, buf, len);
3478 						payload_len += len;
3479 						target_name_printed = 1;
3480 						if (len > skip_bytes)
3481 							skip_bytes = 0;
3482 					}
3483 				}
3484 
3485 				if (inaddr_any)
3486 					sockaddr = &conn->local_sockaddr;
3487 				else
3488 					sockaddr = &np->np_sockaddr;
3489 
3490 				len = sprintf(buf, "TargetAddress="
3491 					      "%pISpc,%hu",
3492 					      sockaddr,
3493 					      tpg->tpgt);
3494 				len += 1;
3495 
3496 				if ((len + payload_len) > buffer_len) {
3497 					spin_unlock(&tpg->tpg_np_lock);
3498 					spin_unlock(&tiqn->tiqn_tpg_lock);
3499 					end_of_buf = 1;
3500 					goto eob;
3501 				}
3502 
3503 				if (skip_bytes && len <= skip_bytes) {
3504 					skip_bytes -= len;
3505 				} else {
3506 					memcpy(payload + payload_len, buf, len);
3507 					payload_len += len;
3508 					if (len > skip_bytes)
3509 						skip_bytes = 0;
3510 				}
3511 			}
3512 			spin_unlock(&tpg->tpg_np_lock);
3513 		}
3514 		spin_unlock(&tiqn->tiqn_tpg_lock);
3515 eob:
3516 		if (end_of_buf) {
3517 			*completed = false;
3518 			break;
3519 		}
3520 
3521 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3522 			break;
3523 	}
3524 	spin_unlock(&tiqn_lock);
3525 
3526 	cmd->buf_ptr = payload;
3527 
3528 	return payload_len;
3529 }
3530 
3531 int
3532 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3533 		      struct iscsi_text_rsp *hdr,
3534 		      enum iscsit_transport_type network_transport)
3535 {
3536 	int text_length, padding;
3537 	bool completed = true;
3538 
3539 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3540 							cmd->read_data_done,
3541 							&completed);
3542 	if (text_length < 0)
3543 		return text_length;
3544 
3545 	if (completed) {
3546 		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3547 	} else {
3548 		hdr->flags |= ISCSI_FLAG_TEXT_CONTINUE;
3549 		cmd->read_data_done += text_length;
3550 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3551 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3552 	}
3553 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3554 	padding = ((-text_length) & 3);
3555 	hton24(hdr->dlength, text_length);
3556 	hdr->itt = cmd->init_task_tag;
3557 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3558 	cmd->stat_sn = conn->stat_sn++;
3559 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3560 
3561 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3562 	/*
3563 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3564 	 * correctly increment MaxCmdSN for each response answering a
3565 	 * non immediate text request with a valid CmdSN.
3566 	 */
3567 	cmd->maxcmdsn_inc = 0;
3568 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3569 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3570 
3571 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3572 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3573 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3574 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3575 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3576 
3577 	return text_length + padding;
3578 }
3579 EXPORT_SYMBOL(iscsit_build_text_rsp);
3580 
3581 static int iscsit_send_text_rsp(
3582 	struct iscsi_cmd *cmd,
3583 	struct iscsi_conn *conn)
3584 {
3585 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3586 	struct kvec *iov;
3587 	u32 tx_size = 0;
3588 	int text_length, iov_count = 0, rc;
3589 
3590 	rc = iscsit_build_text_rsp(cmd, conn, hdr, ISCSI_TCP);
3591 	if (rc < 0)
3592 		return rc;
3593 
3594 	text_length = rc;
3595 	iov = &cmd->iov_misc[0];
3596 	iov[iov_count].iov_base = cmd->pdu;
3597 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3598 	iov[iov_count].iov_base	= cmd->buf_ptr;
3599 	iov[iov_count++].iov_len = text_length;
3600 
3601 	tx_size += (ISCSI_HDR_LEN + text_length);
3602 
3603 	if (conn->conn_ops->HeaderDigest) {
3604 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3605 
3606 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
3607 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3608 
3609 		iov[0].iov_len += ISCSI_CRC_LEN;
3610 		tx_size += ISCSI_CRC_LEN;
3611 		pr_debug("Attaching CRC32 HeaderDigest for"
3612 			" Text Response PDU 0x%08x\n", *header_digest);
3613 	}
3614 
3615 	if (conn->conn_ops->DataDigest) {
3616 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
3617 				cmd->buf_ptr, text_length,
3618 				0, NULL, (u8 *)&cmd->data_crc);
3619 
3620 		iov[iov_count].iov_base	= &cmd->data_crc;
3621 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3622 		tx_size	+= ISCSI_CRC_LEN;
3623 
3624 		pr_debug("Attaching DataDigest for %u bytes of text"
3625 			" data, CRC 0x%08x\n", text_length,
3626 			cmd->data_crc);
3627 	}
3628 
3629 	cmd->iov_misc_count = iov_count;
3630 	cmd->tx_size = tx_size;
3631 
3632 	return 0;
3633 }
3634 
3635 void
3636 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3637 		    struct iscsi_reject *hdr)
3638 {
3639 	hdr->opcode		= ISCSI_OP_REJECT;
3640 	hdr->reason		= cmd->reject_reason;
3641 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3642 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3643 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3644 	cmd->stat_sn		= conn->stat_sn++;
3645 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3646 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3647 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3648 
3649 }
3650 EXPORT_SYMBOL(iscsit_build_reject);
3651 
3652 static int iscsit_send_reject(
3653 	struct iscsi_cmd *cmd,
3654 	struct iscsi_conn *conn)
3655 {
3656 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3657 	struct kvec *iov;
3658 	u32 iov_count = 0, tx_size;
3659 
3660 	iscsit_build_reject(cmd, conn, hdr);
3661 
3662 	iov = &cmd->iov_misc[0];
3663 	iov[iov_count].iov_base = cmd->pdu;
3664 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3665 	iov[iov_count].iov_base = cmd->buf_ptr;
3666 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3667 
3668 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3669 
3670 	if (conn->conn_ops->HeaderDigest) {
3671 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3672 
3673 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
3674 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3675 
3676 		iov[0].iov_len += ISCSI_CRC_LEN;
3677 		tx_size += ISCSI_CRC_LEN;
3678 		pr_debug("Attaching CRC32 HeaderDigest for"
3679 			" REJECT PDU 0x%08x\n", *header_digest);
3680 	}
3681 
3682 	if (conn->conn_ops->DataDigest) {
3683 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->buf_ptr,
3684 				ISCSI_HDR_LEN, 0, NULL, (u8 *)&cmd->data_crc);
3685 
3686 		iov[iov_count].iov_base = &cmd->data_crc;
3687 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3688 		tx_size += ISCSI_CRC_LEN;
3689 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3690 				" PDU 0x%08x\n", cmd->data_crc);
3691 	}
3692 
3693 	cmd->iov_misc_count = iov_count;
3694 	cmd->tx_size = tx_size;
3695 
3696 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3697 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3698 
3699 	return 0;
3700 }
3701 
3702 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3703 {
3704 	int ord, cpu;
3705 	/*
3706 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3707 	 * within iscsit_start_kthreads()
3708 	 *
3709 	 * Here we use bitmap_id to determine which CPU that this
3710 	 * iSCSI connection's RX/TX threads will be scheduled to
3711 	 * execute upon.
3712 	 */
3713 	ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3714 	for_each_online_cpu(cpu) {
3715 		if (ord-- == 0) {
3716 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3717 			return;
3718 		}
3719 	}
3720 	/*
3721 	 * This should never be reached..
3722 	 */
3723 	dump_stack();
3724 	cpumask_setall(conn->conn_cpumask);
3725 }
3726 
3727 static inline void iscsit_thread_check_cpumask(
3728 	struct iscsi_conn *conn,
3729 	struct task_struct *p,
3730 	int mode)
3731 {
3732 	/*
3733 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3734 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3735 	 */
3736 	if (mode == 1) {
3737 		if (!conn->conn_tx_reset_cpumask)
3738 			return;
3739 		conn->conn_tx_reset_cpumask = 0;
3740 	} else {
3741 		if (!conn->conn_rx_reset_cpumask)
3742 			return;
3743 		conn->conn_rx_reset_cpumask = 0;
3744 	}
3745 	/*
3746 	 * Update the CPU mask for this single kthread so that
3747 	 * both TX and RX kthreads are scheduled to run on the
3748 	 * same CPU.
3749 	 */
3750 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3751 }
3752 
3753 static int
3754 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3755 {
3756 	int ret;
3757 
3758 	switch (state) {
3759 	case ISTATE_SEND_R2T:
3760 		ret = iscsit_send_r2t(cmd, conn);
3761 		if (ret < 0)
3762 			goto err;
3763 		break;
3764 	case ISTATE_REMOVE:
3765 		spin_lock_bh(&conn->cmd_lock);
3766 		list_del_init(&cmd->i_conn_node);
3767 		spin_unlock_bh(&conn->cmd_lock);
3768 
3769 		iscsit_free_cmd(cmd, false);
3770 		break;
3771 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3772 		iscsit_mod_nopin_response_timer(conn);
3773 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3774 		if (ret < 0)
3775 			goto err;
3776 		break;
3777 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3778 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3779 		if (ret < 0)
3780 			goto err;
3781 		break;
3782 	default:
3783 		pr_err("Unknown Opcode: 0x%02x ITT:"
3784 		       " 0x%08x, i_state: %d on CID: %hu\n",
3785 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3786 		       conn->cid);
3787 		goto err;
3788 	}
3789 
3790 	return 0;
3791 
3792 err:
3793 	return -1;
3794 }
3795 
3796 static int
3797 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3798 {
3799 	struct iscsit_transport *t = conn->conn_transport;
3800 	struct iscsi_queue_req *qr;
3801 	struct iscsi_cmd *cmd;
3802 	u8 state;
3803 	int ret;
3804 
3805 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3806 		atomic_set(&conn->check_immediate_queue, 0);
3807 		cmd = qr->cmd;
3808 		state = qr->state;
3809 		kmem_cache_free(lio_qr_cache, qr);
3810 
3811 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3812 		if (ret < 0)
3813 			return ret;
3814 	}
3815 
3816 	return 0;
3817 }
3818 
3819 static int
3820 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3821 {
3822 	int ret;
3823 
3824 check_rsp_state:
3825 	switch (state) {
3826 	case ISTATE_SEND_DATAIN:
3827 		ret = iscsit_send_datain(cmd, conn);
3828 		if (ret < 0)
3829 			goto err;
3830 		else if (!ret)
3831 			/* more drs */
3832 			goto check_rsp_state;
3833 		else if (ret == 1) {
3834 			/* all done */
3835 			spin_lock_bh(&cmd->istate_lock);
3836 			cmd->i_state = ISTATE_SENT_STATUS;
3837 			spin_unlock_bh(&cmd->istate_lock);
3838 
3839 			if (atomic_read(&conn->check_immediate_queue))
3840 				return 1;
3841 
3842 			return 0;
3843 		} else if (ret == 2) {
3844 			/* Still must send status,
3845 			   SCF_TRANSPORT_TASK_SENSE was set */
3846 			spin_lock_bh(&cmd->istate_lock);
3847 			cmd->i_state = ISTATE_SEND_STATUS;
3848 			spin_unlock_bh(&cmd->istate_lock);
3849 			state = ISTATE_SEND_STATUS;
3850 			goto check_rsp_state;
3851 		}
3852 
3853 		break;
3854 	case ISTATE_SEND_STATUS:
3855 	case ISTATE_SEND_STATUS_RECOVERY:
3856 		ret = iscsit_send_response(cmd, conn);
3857 		break;
3858 	case ISTATE_SEND_LOGOUTRSP:
3859 		ret = iscsit_send_logout(cmd, conn);
3860 		break;
3861 	case ISTATE_SEND_ASYNCMSG:
3862 		ret = iscsit_send_conn_drop_async_message(
3863 			cmd, conn);
3864 		break;
3865 	case ISTATE_SEND_NOPIN:
3866 		ret = iscsit_send_nopin(cmd, conn);
3867 		break;
3868 	case ISTATE_SEND_REJECT:
3869 		ret = iscsit_send_reject(cmd, conn);
3870 		break;
3871 	case ISTATE_SEND_TASKMGTRSP:
3872 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3873 		if (ret != 0)
3874 			break;
3875 		ret = iscsit_tmr_post_handler(cmd, conn);
3876 		if (ret != 0)
3877 			iscsit_fall_back_to_erl0(conn->sess);
3878 		break;
3879 	case ISTATE_SEND_TEXTRSP:
3880 		ret = iscsit_send_text_rsp(cmd, conn);
3881 		break;
3882 	default:
3883 		pr_err("Unknown Opcode: 0x%02x ITT:"
3884 		       " 0x%08x, i_state: %d on CID: %hu\n",
3885 		       cmd->iscsi_opcode, cmd->init_task_tag,
3886 		       state, conn->cid);
3887 		goto err;
3888 	}
3889 	if (ret < 0)
3890 		goto err;
3891 
3892 	if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3893 		iscsit_tx_thread_wait_for_tcp(conn);
3894 		iscsit_unmap_iovec(cmd);
3895 		goto err;
3896 	}
3897 	iscsit_unmap_iovec(cmd);
3898 
3899 	switch (state) {
3900 	case ISTATE_SEND_LOGOUTRSP:
3901 		if (!iscsit_logout_post_handler(cmd, conn))
3902 			return -ECONNRESET;
3903 		/* fall through */
3904 	case ISTATE_SEND_STATUS:
3905 	case ISTATE_SEND_ASYNCMSG:
3906 	case ISTATE_SEND_NOPIN:
3907 	case ISTATE_SEND_STATUS_RECOVERY:
3908 	case ISTATE_SEND_TEXTRSP:
3909 	case ISTATE_SEND_TASKMGTRSP:
3910 	case ISTATE_SEND_REJECT:
3911 		spin_lock_bh(&cmd->istate_lock);
3912 		cmd->i_state = ISTATE_SENT_STATUS;
3913 		spin_unlock_bh(&cmd->istate_lock);
3914 		break;
3915 	default:
3916 		pr_err("Unknown Opcode: 0x%02x ITT:"
3917 		       " 0x%08x, i_state: %d on CID: %hu\n",
3918 		       cmd->iscsi_opcode, cmd->init_task_tag,
3919 		       cmd->i_state, conn->cid);
3920 		goto err;
3921 	}
3922 
3923 	if (atomic_read(&conn->check_immediate_queue))
3924 		return 1;
3925 
3926 	return 0;
3927 
3928 err:
3929 	return -1;
3930 }
3931 
3932 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3933 {
3934 	struct iscsit_transport *t = conn->conn_transport;
3935 	struct iscsi_queue_req *qr;
3936 	struct iscsi_cmd *cmd;
3937 	u8 state;
3938 	int ret;
3939 
3940 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3941 		cmd = qr->cmd;
3942 		state = qr->state;
3943 		kmem_cache_free(lio_qr_cache, qr);
3944 
3945 		ret = t->iscsit_response_queue(conn, cmd, state);
3946 		if (ret == 1 || ret < 0)
3947 			return ret;
3948 	}
3949 
3950 	return 0;
3951 }
3952 
3953 int iscsi_target_tx_thread(void *arg)
3954 {
3955 	int ret = 0;
3956 	struct iscsi_conn *conn = arg;
3957 	/*
3958 	 * Allow ourselves to be interrupted by SIGINT so that a
3959 	 * connection recovery / failure event can be triggered externally.
3960 	 */
3961 	allow_signal(SIGINT);
3962 
3963 	while (!kthread_should_stop()) {
3964 		/*
3965 		 * Ensure that both TX and RX per connection kthreads
3966 		 * are scheduled to run on the same CPU.
3967 		 */
3968 		iscsit_thread_check_cpumask(conn, current, 1);
3969 
3970 		wait_event_interruptible(conn->queues_wq,
3971 					 !iscsit_conn_all_queues_empty(conn));
3972 
3973 		if (signal_pending(current))
3974 			goto transport_err;
3975 
3976 get_immediate:
3977 		ret = iscsit_handle_immediate_queue(conn);
3978 		if (ret < 0)
3979 			goto transport_err;
3980 
3981 		ret = iscsit_handle_response_queue(conn);
3982 		if (ret == 1)
3983 			goto get_immediate;
3984 		else if (ret == -ECONNRESET)
3985 			goto out;
3986 		else if (ret < 0)
3987 			goto transport_err;
3988 	}
3989 
3990 transport_err:
3991 	/*
3992 	 * Avoid the normal connection failure code-path if this connection
3993 	 * is still within LOGIN mode, and iscsi_np process context is
3994 	 * responsible for cleaning up the early connection failure.
3995 	 */
3996 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3997 		iscsit_take_action_for_connection_exit(conn);
3998 out:
3999 	return 0;
4000 }
4001 
4002 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
4003 {
4004 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
4005 	struct iscsi_cmd *cmd;
4006 	int ret = 0;
4007 
4008 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
4009 	case ISCSI_OP_SCSI_CMD:
4010 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4011 		if (!cmd)
4012 			goto reject;
4013 
4014 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
4015 		break;
4016 	case ISCSI_OP_SCSI_DATA_OUT:
4017 		ret = iscsit_handle_data_out(conn, buf);
4018 		break;
4019 	case ISCSI_OP_NOOP_OUT:
4020 		cmd = NULL;
4021 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
4022 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4023 			if (!cmd)
4024 				goto reject;
4025 		}
4026 		ret = iscsit_handle_nop_out(conn, cmd, buf);
4027 		break;
4028 	case ISCSI_OP_SCSI_TMFUNC:
4029 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4030 		if (!cmd)
4031 			goto reject;
4032 
4033 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
4034 		break;
4035 	case ISCSI_OP_TEXT:
4036 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
4037 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
4038 			if (!cmd)
4039 				goto reject;
4040 		} else {
4041 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4042 			if (!cmd)
4043 				goto reject;
4044 		}
4045 
4046 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
4047 		break;
4048 	case ISCSI_OP_LOGOUT:
4049 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4050 		if (!cmd)
4051 			goto reject;
4052 
4053 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
4054 		if (ret > 0)
4055 			wait_for_completion_timeout(&conn->conn_logout_comp,
4056 					SECONDS_FOR_LOGOUT_COMP * HZ);
4057 		break;
4058 	case ISCSI_OP_SNACK:
4059 		ret = iscsit_handle_snack(conn, buf);
4060 		break;
4061 	default:
4062 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
4063 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
4064 			pr_err("Cannot recover from unknown"
4065 			" opcode while ERL=0, closing iSCSI connection.\n");
4066 			return -1;
4067 		}
4068 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
4069 		       " closing iSCSI connection.\n");
4070 		ret = -1;
4071 		break;
4072 	}
4073 
4074 	return ret;
4075 reject:
4076 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4077 }
4078 
4079 static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
4080 {
4081 	bool ret;
4082 
4083 	spin_lock_bh(&conn->state_lock);
4084 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
4085 	spin_unlock_bh(&conn->state_lock);
4086 
4087 	return ret;
4088 }
4089 
4090 int iscsi_target_rx_thread(void *arg)
4091 {
4092 	int ret, rc;
4093 	u8 buffer[ISCSI_HDR_LEN], opcode;
4094 	u32 checksum = 0, digest = 0;
4095 	struct iscsi_conn *conn = arg;
4096 	struct kvec iov;
4097 	/*
4098 	 * Allow ourselves to be interrupted by SIGINT so that a
4099 	 * connection recovery / failure event can be triggered externally.
4100 	 */
4101 	allow_signal(SIGINT);
4102 	/*
4103 	 * Wait for iscsi_post_login_handler() to complete before allowing
4104 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4105 	 */
4106 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4107 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4108 		return 0;
4109 
4110 	if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
4111 		struct completion comp;
4112 
4113 		init_completion(&comp);
4114 		rc = wait_for_completion_interruptible(&comp);
4115 		if (rc < 0)
4116 			goto transport_err;
4117 
4118 		goto transport_err;
4119 	}
4120 
4121 	while (!kthread_should_stop()) {
4122 		/*
4123 		 * Ensure that both TX and RX per connection kthreads
4124 		 * are scheduled to run on the same CPU.
4125 		 */
4126 		iscsit_thread_check_cpumask(conn, current, 0);
4127 
4128 		memset(buffer, 0, ISCSI_HDR_LEN);
4129 		memset(&iov, 0, sizeof(struct kvec));
4130 
4131 		iov.iov_base	= buffer;
4132 		iov.iov_len	= ISCSI_HDR_LEN;
4133 
4134 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4135 		if (ret != ISCSI_HDR_LEN) {
4136 			iscsit_rx_thread_wait_for_tcp(conn);
4137 			goto transport_err;
4138 		}
4139 
4140 		if (conn->conn_ops->HeaderDigest) {
4141 			iov.iov_base	= &digest;
4142 			iov.iov_len	= ISCSI_CRC_LEN;
4143 
4144 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4145 			if (ret != ISCSI_CRC_LEN) {
4146 				iscsit_rx_thread_wait_for_tcp(conn);
4147 				goto transport_err;
4148 			}
4149 
4150 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
4151 					buffer, ISCSI_HDR_LEN,
4152 					0, NULL, (u8 *)&checksum);
4153 
4154 			if (digest != checksum) {
4155 				pr_err("HeaderDigest CRC32C failed,"
4156 					" received 0x%08x, computed 0x%08x\n",
4157 					digest, checksum);
4158 				/*
4159 				 * Set the PDU to 0xff so it will intentionally
4160 				 * hit default in the switch below.
4161 				 */
4162 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4163 				atomic_long_inc(&conn->sess->conn_digest_errors);
4164 			} else {
4165 				pr_debug("Got HeaderDigest CRC32C"
4166 						" 0x%08x\n", checksum);
4167 			}
4168 		}
4169 
4170 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4171 			goto transport_err;
4172 
4173 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4174 
4175 		if (conn->sess->sess_ops->SessionType &&
4176 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4177 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4178 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4179 			" while in Discovery Session, rejecting.\n", opcode);
4180 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4181 					  buffer);
4182 			goto transport_err;
4183 		}
4184 
4185 		ret = iscsi_target_rx_opcode(conn, buffer);
4186 		if (ret < 0)
4187 			goto transport_err;
4188 	}
4189 
4190 transport_err:
4191 	if (!signal_pending(current))
4192 		atomic_set(&conn->transport_failed, 1);
4193 	iscsit_take_action_for_connection_exit(conn);
4194 	return 0;
4195 }
4196 
4197 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4198 {
4199 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4200 	struct iscsi_session *sess = conn->sess;
4201 	/*
4202 	 * We expect this function to only ever be called from either RX or TX
4203 	 * thread context via iscsit_close_connection() once the other context
4204 	 * has been reset -> returned sleeping pre-handler state.
4205 	 */
4206 	spin_lock_bh(&conn->cmd_lock);
4207 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
4208 
4209 		list_del_init(&cmd->i_conn_node);
4210 		spin_unlock_bh(&conn->cmd_lock);
4211 
4212 		iscsit_increment_maxcmdsn(cmd, sess);
4213 
4214 		iscsit_free_cmd(cmd, true);
4215 
4216 		spin_lock_bh(&conn->cmd_lock);
4217 	}
4218 	spin_unlock_bh(&conn->cmd_lock);
4219 }
4220 
4221 static void iscsit_stop_timers_for_cmds(
4222 	struct iscsi_conn *conn)
4223 {
4224 	struct iscsi_cmd *cmd;
4225 
4226 	spin_lock_bh(&conn->cmd_lock);
4227 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4228 		if (cmd->data_direction == DMA_TO_DEVICE)
4229 			iscsit_stop_dataout_timer(cmd);
4230 	}
4231 	spin_unlock_bh(&conn->cmd_lock);
4232 }
4233 
4234 int iscsit_close_connection(
4235 	struct iscsi_conn *conn)
4236 {
4237 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4238 	struct iscsi_session	*sess = conn->sess;
4239 
4240 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4241 		" %u\n", conn->cid, sess->sid);
4242 	/*
4243 	 * Always up conn_logout_comp for the traditional TCP case just in case
4244 	 * the RX Thread in iscsi_target_rx_opcode() is sleeping and the logout
4245 	 * response never got sent because the connection failed.
4246 	 *
4247 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4248 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4249 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4250 	 * and to avoid iscsi_conn pointer dereference in iser-target code.
4251 	 */
4252 	if (conn->conn_transport->transport_type == ISCSI_TCP)
4253 		complete(&conn->conn_logout_comp);
4254 
4255 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4256 		if (conn->tx_thread &&
4257 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4258 			send_sig(SIGINT, conn->tx_thread, 1);
4259 			kthread_stop(conn->tx_thread);
4260 		}
4261 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4262 		if (conn->rx_thread &&
4263 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4264 			send_sig(SIGINT, conn->rx_thread, 1);
4265 			kthread_stop(conn->rx_thread);
4266 		}
4267 	}
4268 
4269 	spin_lock(&iscsit_global->ts_bitmap_lock);
4270 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4271 			      get_order(1));
4272 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4273 
4274 	iscsit_stop_timers_for_cmds(conn);
4275 	iscsit_stop_nopin_response_timer(conn);
4276 	iscsit_stop_nopin_timer(conn);
4277 
4278 	if (conn->conn_transport->iscsit_wait_conn)
4279 		conn->conn_transport->iscsit_wait_conn(conn);
4280 
4281 	/*
4282 	 * During Connection recovery drop unacknowledged out of order
4283 	 * commands for this connection, and prepare the other commands
4284 	 * for realligence.
4285 	 *
4286 	 * During normal operation clear the out of order commands (but
4287 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4288 	 * struct iscsi_cmds.
4289 	 */
4290 	if (atomic_read(&conn->connection_recovery)) {
4291 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4292 		iscsit_prepare_cmds_for_realligance(conn);
4293 	} else {
4294 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4295 		iscsit_release_commands_from_conn(conn);
4296 	}
4297 	iscsit_free_queue_reqs_for_conn(conn);
4298 
4299 	/*
4300 	 * Handle decrementing session or connection usage count if
4301 	 * a logout response was not able to be sent because the
4302 	 * connection failed.  Fall back to Session Recovery here.
4303 	 */
4304 	if (atomic_read(&conn->conn_logout_remove)) {
4305 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4306 			iscsit_dec_conn_usage_count(conn);
4307 			iscsit_dec_session_usage_count(sess);
4308 		}
4309 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4310 			iscsit_dec_conn_usage_count(conn);
4311 
4312 		atomic_set(&conn->conn_logout_remove, 0);
4313 		atomic_set(&sess->session_reinstatement, 0);
4314 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4315 	}
4316 
4317 	spin_lock_bh(&sess->conn_lock);
4318 	list_del(&conn->conn_list);
4319 
4320 	/*
4321 	 * Attempt to let the Initiator know this connection failed by
4322 	 * sending an Connection Dropped Async Message on another
4323 	 * active connection.
4324 	 */
4325 	if (atomic_read(&conn->connection_recovery))
4326 		iscsit_build_conn_drop_async_message(conn);
4327 
4328 	spin_unlock_bh(&sess->conn_lock);
4329 
4330 	/*
4331 	 * If connection reinstatement is being performed on this connection,
4332 	 * up the connection reinstatement semaphore that is being blocked on
4333 	 * in iscsit_cause_connection_reinstatement().
4334 	 */
4335 	spin_lock_bh(&conn->state_lock);
4336 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4337 		spin_unlock_bh(&conn->state_lock);
4338 		complete(&conn->conn_wait_comp);
4339 		wait_for_completion(&conn->conn_post_wait_comp);
4340 		spin_lock_bh(&conn->state_lock);
4341 	}
4342 
4343 	/*
4344 	 * If connection reinstatement is being performed on this connection
4345 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4346 	 * connection wait rcfr semaphore that is being blocked on
4347 	 * an iscsit_connection_reinstatement_rcfr().
4348 	 */
4349 	if (atomic_read(&conn->connection_wait_rcfr)) {
4350 		spin_unlock_bh(&conn->state_lock);
4351 		complete(&conn->conn_wait_rcfr_comp);
4352 		wait_for_completion(&conn->conn_post_wait_comp);
4353 		spin_lock_bh(&conn->state_lock);
4354 	}
4355 	atomic_set(&conn->connection_reinstatement, 1);
4356 	spin_unlock_bh(&conn->state_lock);
4357 
4358 	/*
4359 	 * If any other processes are accessing this connection pointer we
4360 	 * must wait until they have completed.
4361 	 */
4362 	iscsit_check_conn_usage_count(conn);
4363 
4364 	ahash_request_free(conn->conn_tx_hash);
4365 	if (conn->conn_rx_hash) {
4366 		struct crypto_ahash *tfm;
4367 
4368 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4369 		ahash_request_free(conn->conn_rx_hash);
4370 		crypto_free_ahash(tfm);
4371 	}
4372 
4373 	free_cpumask_var(conn->conn_cpumask);
4374 
4375 	kfree(conn->conn_ops);
4376 	conn->conn_ops = NULL;
4377 
4378 	if (conn->sock)
4379 		sock_release(conn->sock);
4380 
4381 	if (conn->conn_transport->iscsit_free_conn)
4382 		conn->conn_transport->iscsit_free_conn(conn);
4383 
4384 	iscsit_put_transport(conn->conn_transport);
4385 
4386 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4387 	conn->conn_state = TARG_CONN_STATE_FREE;
4388 	kfree(conn);
4389 
4390 	spin_lock_bh(&sess->conn_lock);
4391 	atomic_dec(&sess->nconn);
4392 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4393 		" %s\n", atomic_read(&sess->nconn),
4394 		sess->sess_ops->InitiatorName);
4395 	/*
4396 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4397 	 * Session that they all fail.
4398 	 */
4399 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4400 	     !atomic_read(&sess->session_logout))
4401 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4402 
4403 	/*
4404 	 * If this was not the last connection in the session, and we are
4405 	 * performing session reinstatement or falling back to ERL=0, call
4406 	 * iscsit_stop_session() without sleeping to shutdown the other
4407 	 * active connections.
4408 	 */
4409 	if (atomic_read(&sess->nconn)) {
4410 		if (!atomic_read(&sess->session_reinstatement) &&
4411 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4412 			spin_unlock_bh(&sess->conn_lock);
4413 			return 0;
4414 		}
4415 		if (!atomic_read(&sess->session_stop_active)) {
4416 			atomic_set(&sess->session_stop_active, 1);
4417 			spin_unlock_bh(&sess->conn_lock);
4418 			iscsit_stop_session(sess, 0, 0);
4419 			return 0;
4420 		}
4421 		spin_unlock_bh(&sess->conn_lock);
4422 		return 0;
4423 	}
4424 
4425 	/*
4426 	 * If this was the last connection in the session and one of the
4427 	 * following is occurring:
4428 	 *
4429 	 * Session Reinstatement is not being performed, and are falling back
4430 	 * to ERL=0 call iscsit_close_session().
4431 	 *
4432 	 * Session Logout was requested.  iscsit_close_session() will be called
4433 	 * elsewhere.
4434 	 *
4435 	 * Session Continuation is not being performed, start the Time2Retain
4436 	 * handler and check if sleep_on_sess_wait_sem is active.
4437 	 */
4438 	if (!atomic_read(&sess->session_reinstatement) &&
4439 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4440 		spin_unlock_bh(&sess->conn_lock);
4441 		target_put_session(sess->se_sess);
4442 
4443 		return 0;
4444 	} else if (atomic_read(&sess->session_logout)) {
4445 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4446 		sess->session_state = TARG_SESS_STATE_FREE;
4447 		spin_unlock_bh(&sess->conn_lock);
4448 
4449 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4450 			complete(&sess->session_wait_comp);
4451 
4452 		return 0;
4453 	} else {
4454 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4455 		sess->session_state = TARG_SESS_STATE_FAILED;
4456 
4457 		if (!atomic_read(&sess->session_continuation)) {
4458 			spin_unlock_bh(&sess->conn_lock);
4459 			iscsit_start_time2retain_handler(sess);
4460 		} else
4461 			spin_unlock_bh(&sess->conn_lock);
4462 
4463 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4464 			complete(&sess->session_wait_comp);
4465 
4466 		return 0;
4467 	}
4468 }
4469 
4470 int iscsit_close_session(struct iscsi_session *sess)
4471 {
4472 	struct iscsi_portal_group *tpg = sess->tpg;
4473 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4474 
4475 	if (atomic_read(&sess->nconn)) {
4476 		pr_err("%d connection(s) still exist for iSCSI session"
4477 			" to %s\n", atomic_read(&sess->nconn),
4478 			sess->sess_ops->InitiatorName);
4479 		BUG();
4480 	}
4481 
4482 	spin_lock_bh(&se_tpg->session_lock);
4483 	atomic_set(&sess->session_logout, 1);
4484 	atomic_set(&sess->session_reinstatement, 1);
4485 	iscsit_stop_time2retain_timer(sess);
4486 	spin_unlock_bh(&se_tpg->session_lock);
4487 
4488 	/*
4489 	 * transport_deregister_session_configfs() will clear the
4490 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4491 	 * can be setting it again with __transport_register_session() in
4492 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4493 	 * completes in iscsi_np context.
4494 	 */
4495 	transport_deregister_session_configfs(sess->se_sess);
4496 
4497 	/*
4498 	 * If any other processes are accessing this session pointer we must
4499 	 * wait until they have completed.  If we are in an interrupt (the
4500 	 * time2retain handler) and contain and active session usage count we
4501 	 * restart the timer and exit.
4502 	 */
4503 	if (!in_interrupt()) {
4504 		if (iscsit_check_session_usage_count(sess) == 1)
4505 			iscsit_stop_session(sess, 1, 1);
4506 	} else {
4507 		if (iscsit_check_session_usage_count(sess) == 2) {
4508 			atomic_set(&sess->session_logout, 0);
4509 			iscsit_start_time2retain_handler(sess);
4510 			return 0;
4511 		}
4512 	}
4513 
4514 	transport_deregister_session(sess->se_sess);
4515 
4516 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4517 		iscsit_free_connection_recovery_entires(sess);
4518 
4519 	iscsit_free_all_ooo_cmdsns(sess);
4520 
4521 	spin_lock_bh(&se_tpg->session_lock);
4522 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4523 	sess->session_state = TARG_SESS_STATE_FREE;
4524 	pr_debug("Released iSCSI session from node: %s\n",
4525 			sess->sess_ops->InitiatorName);
4526 	tpg->nsessions--;
4527 	if (tpg->tpg_tiqn)
4528 		tpg->tpg_tiqn->tiqn_nsessions--;
4529 
4530 	pr_debug("Decremented number of active iSCSI Sessions on"
4531 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4532 
4533 	spin_lock(&sess_idr_lock);
4534 	idr_remove(&sess_idr, sess->session_index);
4535 	spin_unlock(&sess_idr_lock);
4536 
4537 	kfree(sess->sess_ops);
4538 	sess->sess_ops = NULL;
4539 	spin_unlock_bh(&se_tpg->session_lock);
4540 
4541 	kfree(sess);
4542 	return 0;
4543 }
4544 
4545 static void iscsit_logout_post_handler_closesession(
4546 	struct iscsi_conn *conn)
4547 {
4548 	struct iscsi_session *sess = conn->sess;
4549 	int sleep = 1;
4550 	/*
4551 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4552 	 * context during session logout, so clear tx_thread_active and
4553 	 * sleep if iscsit_close_connection() has not already occured.
4554 	 *
4555 	 * Since iser-target invokes this logic from it's own workqueue,
4556 	 * always sleep waiting for RX/TX thread shutdown to complete
4557 	 * within iscsit_close_connection().
4558 	 */
4559 	if (conn->conn_transport->transport_type == ISCSI_TCP)
4560 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4561 
4562 	atomic_set(&conn->conn_logout_remove, 0);
4563 	complete(&conn->conn_logout_comp);
4564 
4565 	iscsit_dec_conn_usage_count(conn);
4566 	iscsit_stop_session(sess, sleep, sleep);
4567 	iscsit_dec_session_usage_count(sess);
4568 	target_put_session(sess->se_sess);
4569 }
4570 
4571 static void iscsit_logout_post_handler_samecid(
4572 	struct iscsi_conn *conn)
4573 {
4574 	int sleep = 1;
4575 
4576 	if (conn->conn_transport->transport_type == ISCSI_TCP)
4577 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4578 
4579 	atomic_set(&conn->conn_logout_remove, 0);
4580 	complete(&conn->conn_logout_comp);
4581 
4582 	iscsit_cause_connection_reinstatement(conn, sleep);
4583 	iscsit_dec_conn_usage_count(conn);
4584 }
4585 
4586 static void iscsit_logout_post_handler_diffcid(
4587 	struct iscsi_conn *conn,
4588 	u16 cid)
4589 {
4590 	struct iscsi_conn *l_conn;
4591 	struct iscsi_session *sess = conn->sess;
4592 	bool conn_found = false;
4593 
4594 	if (!sess)
4595 		return;
4596 
4597 	spin_lock_bh(&sess->conn_lock);
4598 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4599 		if (l_conn->cid == cid) {
4600 			iscsit_inc_conn_usage_count(l_conn);
4601 			conn_found = true;
4602 			break;
4603 		}
4604 	}
4605 	spin_unlock_bh(&sess->conn_lock);
4606 
4607 	if (!conn_found)
4608 		return;
4609 
4610 	if (l_conn->sock)
4611 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4612 
4613 	spin_lock_bh(&l_conn->state_lock);
4614 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4615 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4616 	spin_unlock_bh(&l_conn->state_lock);
4617 
4618 	iscsit_cause_connection_reinstatement(l_conn, 1);
4619 	iscsit_dec_conn_usage_count(l_conn);
4620 }
4621 
4622 /*
4623  *	Return of 0 causes the TX thread to restart.
4624  */
4625 int iscsit_logout_post_handler(
4626 	struct iscsi_cmd *cmd,
4627 	struct iscsi_conn *conn)
4628 {
4629 	int ret = 0;
4630 
4631 	switch (cmd->logout_reason) {
4632 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4633 		switch (cmd->logout_response) {
4634 		case ISCSI_LOGOUT_SUCCESS:
4635 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4636 		default:
4637 			iscsit_logout_post_handler_closesession(conn);
4638 			break;
4639 		}
4640 		ret = 0;
4641 		break;
4642 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4643 		if (conn->cid == cmd->logout_cid) {
4644 			switch (cmd->logout_response) {
4645 			case ISCSI_LOGOUT_SUCCESS:
4646 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4647 			default:
4648 				iscsit_logout_post_handler_samecid(conn);
4649 				break;
4650 			}
4651 			ret = 0;
4652 		} else {
4653 			switch (cmd->logout_response) {
4654 			case ISCSI_LOGOUT_SUCCESS:
4655 				iscsit_logout_post_handler_diffcid(conn,
4656 					cmd->logout_cid);
4657 				break;
4658 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4659 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4660 			default:
4661 				break;
4662 			}
4663 			ret = 1;
4664 		}
4665 		break;
4666 	case ISCSI_LOGOUT_REASON_RECOVERY:
4667 		switch (cmd->logout_response) {
4668 		case ISCSI_LOGOUT_SUCCESS:
4669 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4670 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4671 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4672 		default:
4673 			break;
4674 		}
4675 		ret = 1;
4676 		break;
4677 	default:
4678 		break;
4679 
4680 	}
4681 	return ret;
4682 }
4683 EXPORT_SYMBOL(iscsit_logout_post_handler);
4684 
4685 void iscsit_fail_session(struct iscsi_session *sess)
4686 {
4687 	struct iscsi_conn *conn;
4688 
4689 	spin_lock_bh(&sess->conn_lock);
4690 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4691 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4692 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4693 	}
4694 	spin_unlock_bh(&sess->conn_lock);
4695 
4696 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4697 	sess->session_state = TARG_SESS_STATE_FAILED;
4698 }
4699 
4700 int iscsit_free_session(struct iscsi_session *sess)
4701 {
4702 	u16 conn_count = atomic_read(&sess->nconn);
4703 	struct iscsi_conn *conn, *conn_tmp = NULL;
4704 	int is_last;
4705 
4706 	spin_lock_bh(&sess->conn_lock);
4707 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4708 
4709 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4710 			conn_list) {
4711 		if (conn_count == 0)
4712 			break;
4713 
4714 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4715 			is_last = 1;
4716 		} else {
4717 			iscsit_inc_conn_usage_count(conn_tmp);
4718 			is_last = 0;
4719 		}
4720 		iscsit_inc_conn_usage_count(conn);
4721 
4722 		spin_unlock_bh(&sess->conn_lock);
4723 		iscsit_cause_connection_reinstatement(conn, 1);
4724 		spin_lock_bh(&sess->conn_lock);
4725 
4726 		iscsit_dec_conn_usage_count(conn);
4727 		if (is_last == 0)
4728 			iscsit_dec_conn_usage_count(conn_tmp);
4729 
4730 		conn_count--;
4731 	}
4732 
4733 	if (atomic_read(&sess->nconn)) {
4734 		spin_unlock_bh(&sess->conn_lock);
4735 		wait_for_completion(&sess->session_wait_comp);
4736 	} else
4737 		spin_unlock_bh(&sess->conn_lock);
4738 
4739 	target_put_session(sess->se_sess);
4740 	return 0;
4741 }
4742 
4743 void iscsit_stop_session(
4744 	struct iscsi_session *sess,
4745 	int session_sleep,
4746 	int connection_sleep)
4747 {
4748 	u16 conn_count = atomic_read(&sess->nconn);
4749 	struct iscsi_conn *conn, *conn_tmp = NULL;
4750 	int is_last;
4751 
4752 	spin_lock_bh(&sess->conn_lock);
4753 	if (session_sleep)
4754 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4755 
4756 	if (connection_sleep) {
4757 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4758 				conn_list) {
4759 			if (conn_count == 0)
4760 				break;
4761 
4762 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4763 				is_last = 1;
4764 			} else {
4765 				iscsit_inc_conn_usage_count(conn_tmp);
4766 				is_last = 0;
4767 			}
4768 			iscsit_inc_conn_usage_count(conn);
4769 
4770 			spin_unlock_bh(&sess->conn_lock);
4771 			iscsit_cause_connection_reinstatement(conn, 1);
4772 			spin_lock_bh(&sess->conn_lock);
4773 
4774 			iscsit_dec_conn_usage_count(conn);
4775 			if (is_last == 0)
4776 				iscsit_dec_conn_usage_count(conn_tmp);
4777 			conn_count--;
4778 		}
4779 	} else {
4780 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4781 			iscsit_cause_connection_reinstatement(conn, 0);
4782 	}
4783 
4784 	if (session_sleep && atomic_read(&sess->nconn)) {
4785 		spin_unlock_bh(&sess->conn_lock);
4786 		wait_for_completion(&sess->session_wait_comp);
4787 	} else
4788 		spin_unlock_bh(&sess->conn_lock);
4789 }
4790 
4791 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4792 {
4793 	struct iscsi_session *sess;
4794 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4795 	struct se_session *se_sess, *se_sess_tmp;
4796 	LIST_HEAD(free_list);
4797 	int session_count = 0;
4798 
4799 	spin_lock_bh(&se_tpg->session_lock);
4800 	if (tpg->nsessions && !force) {
4801 		spin_unlock_bh(&se_tpg->session_lock);
4802 		return -1;
4803 	}
4804 
4805 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4806 			sess_list) {
4807 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4808 
4809 		spin_lock(&sess->conn_lock);
4810 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4811 		    atomic_read(&sess->session_logout) ||
4812 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4813 			spin_unlock(&sess->conn_lock);
4814 			continue;
4815 		}
4816 		atomic_set(&sess->session_reinstatement, 1);
4817 		spin_unlock(&sess->conn_lock);
4818 
4819 		list_move_tail(&se_sess->sess_list, &free_list);
4820 	}
4821 	spin_unlock_bh(&se_tpg->session_lock);
4822 
4823 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4824 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4825 
4826 		iscsit_free_session(sess);
4827 		session_count++;
4828 	}
4829 
4830 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4831 			" Group: %hu\n", session_count, tpg->tpgt);
4832 	return 0;
4833 }
4834 
4835 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4836 MODULE_VERSION("4.1.x");
4837 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4838 MODULE_LICENSE("GPL");
4839 
4840 module_init(iscsi_target_init_module);
4841 module_exit(iscsi_target_cleanup_module);
4842