1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18 
19 #include <linux/string.h>
20 #include <linux/kthread.h>
21 #include <linux/crypto.h>
22 #include <linux/completion.h>
23 #include <linux/module.h>
24 #include <linux/idr.h>
25 #include <asm/unaligned.h>
26 #include <scsi/scsi_device.h>
27 #include <scsi/iscsi_proto.h>
28 #include <scsi/scsi_tcq.h>
29 #include <target/target_core_base.h>
30 #include <target/target_core_fabric.h>
31 #include <target/target_core_configfs.h>
32 
33 #include "iscsi_target_core.h"
34 #include "iscsi_target_parameters.h"
35 #include "iscsi_target_seq_pdu_list.h"
36 #include "iscsi_target_tq.h"
37 #include "iscsi_target_configfs.h"
38 #include "iscsi_target_datain_values.h"
39 #include "iscsi_target_erl0.h"
40 #include "iscsi_target_erl1.h"
41 #include "iscsi_target_erl2.h"
42 #include "iscsi_target_login.h"
43 #include "iscsi_target_tmr.h"
44 #include "iscsi_target_tpg.h"
45 #include "iscsi_target_util.h"
46 #include "iscsi_target.h"
47 #include "iscsi_target_device.h"
48 #include "iscsi_target_stat.h"
49 
50 #include <target/iscsi/iscsi_transport.h>
51 
52 static LIST_HEAD(g_tiqn_list);
53 static LIST_HEAD(g_np_list);
54 static DEFINE_SPINLOCK(tiqn_lock);
55 static DEFINE_MUTEX(np_lock);
56 
57 static struct idr tiqn_idr;
58 struct idr sess_idr;
59 struct mutex auth_id_lock;
60 spinlock_t sess_idr_lock;
61 
62 struct iscsit_global *iscsit_global;
63 
64 struct kmem_cache *lio_qr_cache;
65 struct kmem_cache *lio_dr_cache;
66 struct kmem_cache *lio_ooo_cache;
67 struct kmem_cache *lio_r2t_cache;
68 
69 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
70 			struct iscsi_scsi_req *, u32);
71 
72 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
73 {
74 	struct iscsi_tiqn *tiqn = NULL;
75 
76 	spin_lock(&tiqn_lock);
77 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
78 		if (!strcmp(tiqn->tiqn, buf)) {
79 
80 			spin_lock(&tiqn->tiqn_state_lock);
81 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
82 				tiqn->tiqn_access_count++;
83 				spin_unlock(&tiqn->tiqn_state_lock);
84 				spin_unlock(&tiqn_lock);
85 				return tiqn;
86 			}
87 			spin_unlock(&tiqn->tiqn_state_lock);
88 		}
89 	}
90 	spin_unlock(&tiqn_lock);
91 
92 	return NULL;
93 }
94 
95 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
96 {
97 	spin_lock(&tiqn->tiqn_state_lock);
98 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
99 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
100 		spin_unlock(&tiqn->tiqn_state_lock);
101 		return 0;
102 	}
103 	spin_unlock(&tiqn->tiqn_state_lock);
104 
105 	return -1;
106 }
107 
108 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
109 {
110 	spin_lock(&tiqn->tiqn_state_lock);
111 	tiqn->tiqn_access_count--;
112 	spin_unlock(&tiqn->tiqn_state_lock);
113 }
114 
115 /*
116  * Note that IQN formatting is expected to be done in userspace, and
117  * no explict IQN format checks are done here.
118  */
119 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
120 {
121 	struct iscsi_tiqn *tiqn = NULL;
122 	int ret;
123 
124 	if (strlen(buf) >= ISCSI_IQN_LEN) {
125 		pr_err("Target IQN exceeds %d bytes\n",
126 				ISCSI_IQN_LEN);
127 		return ERR_PTR(-EINVAL);
128 	}
129 
130 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
131 	if (!tiqn) {
132 		pr_err("Unable to allocate struct iscsi_tiqn\n");
133 		return ERR_PTR(-ENOMEM);
134 	}
135 
136 	sprintf(tiqn->tiqn, "%s", buf);
137 	INIT_LIST_HEAD(&tiqn->tiqn_list);
138 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
139 	spin_lock_init(&tiqn->tiqn_state_lock);
140 	spin_lock_init(&tiqn->tiqn_tpg_lock);
141 	spin_lock_init(&tiqn->sess_err_stats.lock);
142 	spin_lock_init(&tiqn->login_stats.lock);
143 	spin_lock_init(&tiqn->logout_stats.lock);
144 
145 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
146 
147 	idr_preload(GFP_KERNEL);
148 	spin_lock(&tiqn_lock);
149 
150 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
151 	if (ret < 0) {
152 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
153 		spin_unlock(&tiqn_lock);
154 		idr_preload_end();
155 		kfree(tiqn);
156 		return ERR_PTR(ret);
157 	}
158 	tiqn->tiqn_index = ret;
159 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
160 
161 	spin_unlock(&tiqn_lock);
162 	idr_preload_end();
163 
164 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
165 
166 	return tiqn;
167 
168 }
169 
170 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
171 {
172 	/*
173 	 * Wait for accesses to said struct iscsi_tiqn to end.
174 	 */
175 	spin_lock(&tiqn->tiqn_state_lock);
176 	while (tiqn->tiqn_access_count != 0) {
177 		spin_unlock(&tiqn->tiqn_state_lock);
178 		msleep(10);
179 		spin_lock(&tiqn->tiqn_state_lock);
180 	}
181 	spin_unlock(&tiqn->tiqn_state_lock);
182 }
183 
184 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
185 {
186 	/*
187 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
188 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
189 	 * attempts to access this struct iscsi_tiqn will fail from both transport
190 	 * fabric and control code paths.
191 	 */
192 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
193 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
194 		return;
195 	}
196 
197 	iscsit_wait_for_tiqn(tiqn);
198 
199 	spin_lock(&tiqn_lock);
200 	list_del(&tiqn->tiqn_list);
201 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
202 	spin_unlock(&tiqn_lock);
203 
204 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
205 			tiqn->tiqn);
206 	kfree(tiqn);
207 }
208 
209 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
210 {
211 	int ret;
212 	/*
213 	 * Determine if the network portal is accepting storage traffic.
214 	 */
215 	spin_lock_bh(&np->np_thread_lock);
216 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
217 		spin_unlock_bh(&np->np_thread_lock);
218 		return -1;
219 	}
220 	spin_unlock_bh(&np->np_thread_lock);
221 	/*
222 	 * Determine if the portal group is accepting storage traffic.
223 	 */
224 	spin_lock_bh(&tpg->tpg_state_lock);
225 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
226 		spin_unlock_bh(&tpg->tpg_state_lock);
227 		return -1;
228 	}
229 	spin_unlock_bh(&tpg->tpg_state_lock);
230 
231 	/*
232 	 * Here we serialize access across the TIQN+TPG Tuple.
233 	 */
234 	ret = down_interruptible(&tpg->np_login_sem);
235 	if ((ret != 0) || signal_pending(current))
236 		return -1;
237 
238 	spin_lock_bh(&tpg->tpg_state_lock);
239 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
240 		spin_unlock_bh(&tpg->tpg_state_lock);
241 		up(&tpg->np_login_sem);
242 		return -1;
243 	}
244 	spin_unlock_bh(&tpg->tpg_state_lock);
245 
246 	return 0;
247 }
248 
249 void iscsit_login_kref_put(struct kref *kref)
250 {
251 	struct iscsi_tpg_np *tpg_np = container_of(kref,
252 				struct iscsi_tpg_np, tpg_np_kref);
253 
254 	complete(&tpg_np->tpg_np_comp);
255 }
256 
257 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
258 		       struct iscsi_tpg_np *tpg_np)
259 {
260 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
261 
262 	up(&tpg->np_login_sem);
263 
264 	if (tpg_np)
265 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
266 
267 	if (tiqn)
268 		iscsit_put_tiqn_for_login(tiqn);
269 
270 	return 0;
271 }
272 
273 bool iscsit_check_np_match(
274 	struct __kernel_sockaddr_storage *sockaddr,
275 	struct iscsi_np *np,
276 	int network_transport)
277 {
278 	struct sockaddr_in *sock_in, *sock_in_e;
279 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
280 	bool ip_match = false;
281 	u16 port;
282 
283 	if (sockaddr->ss_family == AF_INET6) {
284 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
285 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
286 
287 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
288 			    &sock_in6_e->sin6_addr.in6_u,
289 			    sizeof(struct in6_addr)))
290 			ip_match = true;
291 
292 		port = ntohs(sock_in6->sin6_port);
293 	} else {
294 		sock_in = (struct sockaddr_in *)sockaddr;
295 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
296 
297 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
298 			ip_match = true;
299 
300 		port = ntohs(sock_in->sin_port);
301 	}
302 
303 	if ((ip_match == true) && (np->np_port == port) &&
304 	    (np->np_network_transport == network_transport))
305 		return true;
306 
307 	return false;
308 }
309 
310 /*
311  * Called with mutex np_lock held
312  */
313 static struct iscsi_np *iscsit_get_np(
314 	struct __kernel_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 == true) {
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 __kernel_sockaddr_storage *sockaddr,
346 	char *ip_str,
347 	int network_transport)
348 {
349 	struct sockaddr_in *sock_in;
350 	struct sockaddr_in6 *sock_in6;
351 	struct iscsi_np *np;
352 	int ret;
353 
354 	mutex_lock(&np_lock);
355 
356 	/*
357 	 * Locate the existing struct iscsi_np if already active..
358 	 */
359 	np = iscsit_get_np(sockaddr, network_transport);
360 	if (np) {
361 		mutex_unlock(&np_lock);
362 		return np;
363 	}
364 
365 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
366 	if (!np) {
367 		pr_err("Unable to allocate memory for struct iscsi_np\n");
368 		mutex_unlock(&np_lock);
369 		return ERR_PTR(-ENOMEM);
370 	}
371 
372 	np->np_flags |= NPF_IP_NETWORK;
373 	if (sockaddr->ss_family == AF_INET6) {
374 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
375 		snprintf(np->np_ip, IPV6_ADDRESS_SPACE, "%s", ip_str);
376 		np->np_port = ntohs(sock_in6->sin6_port);
377 	} else {
378 		sock_in = (struct sockaddr_in *)sockaddr;
379 		sprintf(np->np_ip, "%s", ip_str);
380 		np->np_port = ntohs(sock_in->sin_port);
381 	}
382 
383 	np->np_network_transport = network_transport;
384 	spin_lock_init(&np->np_thread_lock);
385 	init_completion(&np->np_restart_comp);
386 	INIT_LIST_HEAD(&np->np_list);
387 
388 	ret = iscsi_target_setup_login_socket(np, sockaddr);
389 	if (ret != 0) {
390 		kfree(np);
391 		mutex_unlock(&np_lock);
392 		return ERR_PTR(ret);
393 	}
394 
395 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
396 	if (IS_ERR(np->np_thread)) {
397 		pr_err("Unable to create kthread: iscsi_np\n");
398 		ret = PTR_ERR(np->np_thread);
399 		kfree(np);
400 		mutex_unlock(&np_lock);
401 		return ERR_PTR(ret);
402 	}
403 	/*
404 	 * Increment the np_exports reference count now to prevent
405 	 * iscsit_del_np() below from being run while a new call to
406 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
407 	 * active.  We don't need to hold np->np_thread_lock at this
408 	 * point because iscsi_np has not been added to g_np_list yet.
409 	 */
410 	np->np_exports = 1;
411 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
412 
413 	list_add_tail(&np->np_list, &g_np_list);
414 	mutex_unlock(&np_lock);
415 
416 	pr_debug("CORE[0] - Added Network Portal: %s:%hu on %s\n",
417 		np->np_ip, np->np_port, np->np_transport->name);
418 
419 	return np;
420 }
421 
422 int iscsit_reset_np_thread(
423 	struct iscsi_np *np,
424 	struct iscsi_tpg_np *tpg_np,
425 	struct iscsi_portal_group *tpg,
426 	bool shutdown)
427 {
428 	spin_lock_bh(&np->np_thread_lock);
429 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
430 		spin_unlock_bh(&np->np_thread_lock);
431 		return 0;
432 	}
433 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
434 
435 	if (np->np_thread) {
436 		spin_unlock_bh(&np->np_thread_lock);
437 		send_sig(SIGINT, np->np_thread, 1);
438 		wait_for_completion(&np->np_restart_comp);
439 		spin_lock_bh(&np->np_thread_lock);
440 	}
441 	spin_unlock_bh(&np->np_thread_lock);
442 
443 	if (tpg_np && shutdown) {
444 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
445 
446 		wait_for_completion(&tpg_np->tpg_np_comp);
447 	}
448 
449 	return 0;
450 }
451 
452 static void iscsit_free_np(struct iscsi_np *np)
453 {
454 	if (np->np_socket)
455 		sock_release(np->np_socket);
456 }
457 
458 int iscsit_del_np(struct iscsi_np *np)
459 {
460 	spin_lock_bh(&np->np_thread_lock);
461 	np->np_exports--;
462 	if (np->np_exports) {
463 		spin_unlock_bh(&np->np_thread_lock);
464 		return 0;
465 	}
466 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
467 	spin_unlock_bh(&np->np_thread_lock);
468 
469 	if (np->np_thread) {
470 		/*
471 		 * We need to send the signal to wakeup Linux/Net
472 		 * which may be sleeping in sock_accept()..
473 		 */
474 		send_sig(SIGINT, np->np_thread, 1);
475 		kthread_stop(np->np_thread);
476 		np->np_thread = NULL;
477 	}
478 
479 	np->np_transport->iscsit_free_np(np);
480 
481 	mutex_lock(&np_lock);
482 	list_del(&np->np_list);
483 	mutex_unlock(&np_lock);
484 
485 	pr_debug("CORE[0] - Removed Network Portal: %s:%hu on %s\n",
486 		np->np_ip, np->np_port, np->np_transport->name);
487 
488 	iscsit_put_transport(np->np_transport);
489 	kfree(np);
490 	return 0;
491 }
492 
493 static int iscsit_immediate_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
494 static int iscsit_response_queue(struct iscsi_conn *, struct iscsi_cmd *, int);
495 
496 static int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
497 {
498 	iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
499 	return 0;
500 }
501 
502 static void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
503 {
504 	bool scsi_cmd = (cmd->iscsi_opcode == ISCSI_OP_SCSI_CMD);
505 
506 	spin_lock_bh(&conn->cmd_lock);
507 	if (!list_empty(&cmd->i_conn_node))
508 		list_del_init(&cmd->i_conn_node);
509 	spin_unlock_bh(&conn->cmd_lock);
510 
511 	__iscsit_free_cmd(cmd, scsi_cmd, true);
512 }
513 
514 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
515 {
516 	return TARGET_PROT_NORMAL;
517 }
518 
519 static struct iscsit_transport iscsi_target_transport = {
520 	.name			= "iSCSI/TCP",
521 	.transport_type		= ISCSI_TCP,
522 	.owner			= NULL,
523 	.iscsit_setup_np	= iscsit_setup_np,
524 	.iscsit_accept_np	= iscsit_accept_np,
525 	.iscsit_free_np		= iscsit_free_np,
526 	.iscsit_get_login_rx	= iscsit_get_login_rx,
527 	.iscsit_put_login_tx	= iscsit_put_login_tx,
528 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
529 	.iscsit_immediate_queue	= iscsit_immediate_queue,
530 	.iscsit_response_queue	= iscsit_response_queue,
531 	.iscsit_queue_data_in	= iscsit_queue_rsp,
532 	.iscsit_queue_status	= iscsit_queue_rsp,
533 	.iscsit_aborted_task	= iscsit_aborted_task,
534 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
535 };
536 
537 static int __init iscsi_target_init_module(void)
538 {
539 	int ret = 0;
540 
541 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
542 
543 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
544 	if (!iscsit_global) {
545 		pr_err("Unable to allocate memory for iscsit_global\n");
546 		return -1;
547 	}
548 	mutex_init(&auth_id_lock);
549 	spin_lock_init(&sess_idr_lock);
550 	idr_init(&tiqn_idr);
551 	idr_init(&sess_idr);
552 
553 	ret = iscsi_target_register_configfs();
554 	if (ret < 0)
555 		goto out;
556 
557 	ret = iscsi_thread_set_init();
558 	if (ret < 0)
559 		goto configfs_out;
560 
561 	if (iscsi_allocate_thread_sets(TARGET_THREAD_SET_COUNT) !=
562 			TARGET_THREAD_SET_COUNT) {
563 		pr_err("iscsi_allocate_thread_sets() returned"
564 			" unexpected value!\n");
565 		goto ts_out1;
566 	}
567 
568 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
569 			sizeof(struct iscsi_queue_req),
570 			__alignof__(struct iscsi_queue_req), 0, NULL);
571 	if (!lio_qr_cache) {
572 		pr_err("nable to kmem_cache_create() for"
573 				" lio_qr_cache\n");
574 		goto ts_out2;
575 	}
576 
577 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
578 			sizeof(struct iscsi_datain_req),
579 			__alignof__(struct iscsi_datain_req), 0, NULL);
580 	if (!lio_dr_cache) {
581 		pr_err("Unable to kmem_cache_create() for"
582 				" lio_dr_cache\n");
583 		goto qr_out;
584 	}
585 
586 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
587 			sizeof(struct iscsi_ooo_cmdsn),
588 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
589 	if (!lio_ooo_cache) {
590 		pr_err("Unable to kmem_cache_create() for"
591 				" lio_ooo_cache\n");
592 		goto dr_out;
593 	}
594 
595 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
596 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
597 			0, NULL);
598 	if (!lio_r2t_cache) {
599 		pr_err("Unable to kmem_cache_create() for"
600 				" lio_r2t_cache\n");
601 		goto ooo_out;
602 	}
603 
604 	iscsit_register_transport(&iscsi_target_transport);
605 
606 	if (iscsit_load_discovery_tpg() < 0)
607 		goto r2t_out;
608 
609 	return ret;
610 r2t_out:
611 	kmem_cache_destroy(lio_r2t_cache);
612 ooo_out:
613 	kmem_cache_destroy(lio_ooo_cache);
614 dr_out:
615 	kmem_cache_destroy(lio_dr_cache);
616 qr_out:
617 	kmem_cache_destroy(lio_qr_cache);
618 ts_out2:
619 	iscsi_deallocate_thread_sets();
620 ts_out1:
621 	iscsi_thread_set_free();
622 configfs_out:
623 	iscsi_target_deregister_configfs();
624 out:
625 	kfree(iscsit_global);
626 	return -ENOMEM;
627 }
628 
629 static void __exit iscsi_target_cleanup_module(void)
630 {
631 	iscsi_deallocate_thread_sets();
632 	iscsi_thread_set_free();
633 	iscsit_release_discovery_tpg();
634 	iscsit_unregister_transport(&iscsi_target_transport);
635 	kmem_cache_destroy(lio_qr_cache);
636 	kmem_cache_destroy(lio_dr_cache);
637 	kmem_cache_destroy(lio_ooo_cache);
638 	kmem_cache_destroy(lio_r2t_cache);
639 
640 	iscsi_target_deregister_configfs();
641 
642 	kfree(iscsit_global);
643 }
644 
645 static int iscsit_add_reject(
646 	struct iscsi_conn *conn,
647 	u8 reason,
648 	unsigned char *buf)
649 {
650 	struct iscsi_cmd *cmd;
651 
652 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
653 	if (!cmd)
654 		return -1;
655 
656 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
657 	cmd->reject_reason = reason;
658 
659 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
660 	if (!cmd->buf_ptr) {
661 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
662 		iscsit_free_cmd(cmd, false);
663 		return -1;
664 	}
665 
666 	spin_lock_bh(&conn->cmd_lock);
667 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
668 	spin_unlock_bh(&conn->cmd_lock);
669 
670 	cmd->i_state = ISTATE_SEND_REJECT;
671 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
672 
673 	return -1;
674 }
675 
676 static int iscsit_add_reject_from_cmd(
677 	struct iscsi_cmd *cmd,
678 	u8 reason,
679 	bool add_to_conn,
680 	unsigned char *buf)
681 {
682 	struct iscsi_conn *conn;
683 
684 	if (!cmd->conn) {
685 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
686 				cmd->init_task_tag);
687 		return -1;
688 	}
689 	conn = cmd->conn;
690 
691 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
692 	cmd->reject_reason = reason;
693 
694 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
695 	if (!cmd->buf_ptr) {
696 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
697 		iscsit_free_cmd(cmd, false);
698 		return -1;
699 	}
700 
701 	if (add_to_conn) {
702 		spin_lock_bh(&conn->cmd_lock);
703 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
704 		spin_unlock_bh(&conn->cmd_lock);
705 	}
706 
707 	cmd->i_state = ISTATE_SEND_REJECT;
708 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
709 	/*
710 	 * Perform the kref_put now if se_cmd has already been setup by
711 	 * scsit_setup_scsi_cmd()
712 	 */
713 	if (cmd->se_cmd.se_tfo != NULL) {
714 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
715 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
716 	}
717 	return -1;
718 }
719 
720 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
721 				 unsigned char *buf)
722 {
723 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
724 }
725 
726 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
727 {
728 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
729 }
730 
731 /*
732  * Map some portion of the allocated scatterlist to an iovec, suitable for
733  * kernel sockets to copy data in/out.
734  */
735 static int iscsit_map_iovec(
736 	struct iscsi_cmd *cmd,
737 	struct kvec *iov,
738 	u32 data_offset,
739 	u32 data_length)
740 {
741 	u32 i = 0;
742 	struct scatterlist *sg;
743 	unsigned int page_off;
744 
745 	/*
746 	 * We know each entry in t_data_sg contains a page.
747 	 */
748 	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
749 	page_off = (data_offset % PAGE_SIZE);
750 
751 	cmd->first_data_sg = sg;
752 	cmd->first_data_sg_off = page_off;
753 
754 	while (data_length) {
755 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
756 
757 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
758 		iov[i].iov_len = cur_len;
759 
760 		data_length -= cur_len;
761 		page_off = 0;
762 		sg = sg_next(sg);
763 		i++;
764 	}
765 
766 	cmd->kmapped_nents = i;
767 
768 	return i;
769 }
770 
771 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
772 {
773 	u32 i;
774 	struct scatterlist *sg;
775 
776 	sg = cmd->first_data_sg;
777 
778 	for (i = 0; i < cmd->kmapped_nents; i++)
779 		kunmap(sg_page(&sg[i]));
780 }
781 
782 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
783 {
784 	LIST_HEAD(ack_list);
785 	struct iscsi_cmd *cmd, *cmd_p;
786 
787 	conn->exp_statsn = exp_statsn;
788 
789 	if (conn->sess->sess_ops->RDMAExtensions)
790 		return;
791 
792 	spin_lock_bh(&conn->cmd_lock);
793 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
794 		spin_lock(&cmd->istate_lock);
795 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
796 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
797 			cmd->i_state = ISTATE_REMOVE;
798 			spin_unlock(&cmd->istate_lock);
799 			list_move_tail(&cmd->i_conn_node, &ack_list);
800 			continue;
801 		}
802 		spin_unlock(&cmd->istate_lock);
803 	}
804 	spin_unlock_bh(&conn->cmd_lock);
805 
806 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
807 		list_del_init(&cmd->i_conn_node);
808 		iscsit_free_cmd(cmd, false);
809 	}
810 }
811 
812 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
813 {
814 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
815 
816 	iov_count += ISCSI_IOV_DATA_BUFFER;
817 
818 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
819 	if (!cmd->iov_data) {
820 		pr_err("Unable to allocate cmd->iov_data\n");
821 		return -ENOMEM;
822 	}
823 
824 	cmd->orig_iov_data_count = iov_count;
825 	return 0;
826 }
827 
828 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
829 			  unsigned char *buf)
830 {
831 	int data_direction, payload_length;
832 	struct iscsi_scsi_req *hdr;
833 	int iscsi_task_attr;
834 	int sam_task_attr;
835 
836 	atomic_long_inc(&conn->sess->cmd_pdus);
837 
838 	hdr			= (struct iscsi_scsi_req *) buf;
839 	payload_length		= ntoh24(hdr->dlength);
840 
841 	/* FIXME; Add checks for AdditionalHeaderSegment */
842 
843 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
844 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
845 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
846 				" not set. Bad iSCSI Initiator.\n");
847 		return iscsit_add_reject_cmd(cmd,
848 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
849 	}
850 
851 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
852 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
853 		/*
854 		 * From RFC-3720 Section 10.3.1:
855 		 *
856 		 * "Either or both of R and W MAY be 1 when either the
857 		 *  Expected Data Transfer Length and/or Bidirectional Read
858 		 *  Expected Data Transfer Length are 0"
859 		 *
860 		 * For this case, go ahead and clear the unnecssary bits
861 		 * to avoid any confusion with ->data_direction.
862 		 */
863 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
864 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
865 
866 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
867 			" set when Expected Data Transfer Length is 0 for"
868 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
869 	}
870 
871 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
872 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
873 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
874 			" MUST be set if Expected Data Transfer Length is not 0."
875 			" Bad iSCSI Initiator\n");
876 		return iscsit_add_reject_cmd(cmd,
877 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
878 	}
879 
880 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
881 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
882 		pr_err("Bidirectional operations not supported!\n");
883 		return iscsit_add_reject_cmd(cmd,
884 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
885 	}
886 
887 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
888 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
889 				" Scsi Command PDU.\n");
890 		return iscsit_add_reject_cmd(cmd,
891 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
892 	}
893 
894 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
895 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
896 			" protocol error.\n", payload_length);
897 		return iscsit_add_reject_cmd(cmd,
898 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
899 	}
900 
901 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
902 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
903 		pr_err("Expected Data Transfer Length and Length of"
904 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
905 			" bit is not set protocol error\n");
906 		return iscsit_add_reject_cmd(cmd,
907 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
908 	}
909 
910 	if (payload_length > be32_to_cpu(hdr->data_length)) {
911 		pr_err("DataSegmentLength: %u is greater than"
912 			" EDTL: %u, protocol error.\n", payload_length,
913 				hdr->data_length);
914 		return iscsit_add_reject_cmd(cmd,
915 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
916 	}
917 
918 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
919 		pr_err("DataSegmentLength: %u is greater than"
920 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
921 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
922 		return iscsit_add_reject_cmd(cmd,
923 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
924 	}
925 
926 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
927 		pr_err("DataSegmentLength: %u is greater than"
928 			" FirstBurstLength: %u, protocol error.\n",
929 			payload_length, conn->sess->sess_ops->FirstBurstLength);
930 		return iscsit_add_reject_cmd(cmd,
931 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
932 	}
933 
934 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
935 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
936 			  DMA_NONE;
937 
938 	cmd->data_direction = data_direction;
939 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
940 	/*
941 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
942 	 */
943 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
944 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
945 		sam_task_attr = MSG_SIMPLE_TAG;
946 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
947 		sam_task_attr = MSG_ORDERED_TAG;
948 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
949 		sam_task_attr = MSG_HEAD_TAG;
950 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
951 		sam_task_attr = MSG_ACA_TAG;
952 	else {
953 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
954 			" MSG_SIMPLE_TAG\n", iscsi_task_attr);
955 		sam_task_attr = MSG_SIMPLE_TAG;
956 	}
957 
958 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
959 	cmd->i_state		= ISTATE_NEW_CMD;
960 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
961 	cmd->immediate_data	= (payload_length) ? 1 : 0;
962 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
963 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
964 	if (cmd->unsolicited_data)
965 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
966 
967 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
968 	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
969 		spin_lock_bh(&conn->sess->ttt_lock);
970 		cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
971 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
972 			cmd->targ_xfer_tag = conn->sess->targ_xfer_tag++;
973 		spin_unlock_bh(&conn->sess->ttt_lock);
974 	} else if (hdr->flags & ISCSI_FLAG_CMD_WRITE)
975 		cmd->targ_xfer_tag = 0xFFFFFFFF;
976 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
977 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
978 	cmd->first_burst_len	= payload_length;
979 
980 	if (!conn->sess->sess_ops->RDMAExtensions &&
981 	     cmd->data_direction == DMA_FROM_DEVICE) {
982 		struct iscsi_datain_req *dr;
983 
984 		dr = iscsit_allocate_datain_req();
985 		if (!dr)
986 			return iscsit_add_reject_cmd(cmd,
987 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
988 
989 		iscsit_attach_datain_req(cmd, dr);
990 	}
991 
992 	/*
993 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
994 	 */
995 	transport_init_se_cmd(&cmd->se_cmd, &lio_target_fabric_configfs->tf_ops,
996 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
997 			cmd->data_direction, sam_task_attr,
998 			cmd->sense_buffer + 2);
999 
1000 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1001 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1002 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1003 		conn->cid);
1004 
1005 	target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
1006 
1007 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
1008 						     scsilun_to_int(&hdr->lun));
1009 	if (cmd->sense_reason)
1010 		goto attach_cmd;
1011 
1012 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
1013 	if (cmd->sense_reason) {
1014 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1015 			return iscsit_add_reject_cmd(cmd,
1016 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1017 		}
1018 
1019 		goto attach_cmd;
1020 	}
1021 
1022 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1023 		return iscsit_add_reject_cmd(cmd,
1024 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1025 	}
1026 
1027 attach_cmd:
1028 	spin_lock_bh(&conn->cmd_lock);
1029 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1030 	spin_unlock_bh(&conn->cmd_lock);
1031 	/*
1032 	 * Check if we need to delay processing because of ALUA
1033 	 * Active/NonOptimized primary access state..
1034 	 */
1035 	core_alua_check_nonop_delay(&cmd->se_cmd);
1036 
1037 	return 0;
1038 }
1039 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1040 
1041 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1042 {
1043 	iscsit_set_dataout_sequence_values(cmd);
1044 
1045 	spin_lock_bh(&cmd->dataout_timeout_lock);
1046 	iscsit_start_dataout_timer(cmd, cmd->conn);
1047 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1048 }
1049 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1050 
1051 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1052 			    struct iscsi_scsi_req *hdr)
1053 {
1054 	int cmdsn_ret = 0;
1055 	/*
1056 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1057 	 * the Immediate Bit is not set, and no Immediate
1058 	 * Data is attached.
1059 	 *
1060 	 * A PDU/CmdSN carrying Immediate Data can only
1061 	 * be processed after the DataCRC has passed.
1062 	 * If the DataCRC fails, the CmdSN MUST NOT
1063 	 * be acknowledged. (See below)
1064 	 */
1065 	if (!cmd->immediate_data) {
1066 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1067 					(unsigned char *)hdr, hdr->cmdsn);
1068 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1069 			return -1;
1070 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1071 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1072 			return 0;
1073 		}
1074 	}
1075 
1076 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1077 
1078 	/*
1079 	 * If no Immediate Data is attached, it's OK to return now.
1080 	 */
1081 	if (!cmd->immediate_data) {
1082 		if (!cmd->sense_reason && cmd->unsolicited_data)
1083 			iscsit_set_unsoliticed_dataout(cmd);
1084 		if (!cmd->sense_reason)
1085 			return 0;
1086 
1087 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1088 		return 0;
1089 	}
1090 
1091 	/*
1092 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1093 	 * execution.  These exceptions are processed in CmdSN order using
1094 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1095 	 */
1096 	if (cmd->sense_reason) {
1097 		if (cmd->reject_reason)
1098 			return 0;
1099 
1100 		return 1;
1101 	}
1102 	/*
1103 	 * Call directly into transport_generic_new_cmd() to perform
1104 	 * the backend memory allocation.
1105 	 */
1106 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1107 	if (cmd->sense_reason)
1108 		return 1;
1109 
1110 	return 0;
1111 }
1112 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1113 
1114 static int
1115 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1116 			  bool dump_payload)
1117 {
1118 	struct iscsi_conn *conn = cmd->conn;
1119 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1120 	/*
1121 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1122 	 */
1123 	if (dump_payload == true)
1124 		goto after_immediate_data;
1125 
1126 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1127 					cmd->first_burst_len);
1128 after_immediate_data:
1129 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1130 		/*
1131 		 * A PDU/CmdSN carrying Immediate Data passed
1132 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1133 		 * Immediate Bit is not set.
1134 		 */
1135 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1136 					(unsigned char *)hdr, hdr->cmdsn);
1137 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1138 			return -1;
1139 
1140 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1141 			int rc;
1142 
1143 			rc = iscsit_dump_data_payload(cmd->conn,
1144 						      cmd->first_burst_len, 1);
1145 			target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1146 			return rc;
1147 		} else if (cmd->unsolicited_data)
1148 			iscsit_set_unsoliticed_dataout(cmd);
1149 
1150 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1151 		/*
1152 		 * Immediate Data failed DataCRC and ERL>=1,
1153 		 * silently drop this PDU and let the initiator
1154 		 * plug the CmdSN gap.
1155 		 *
1156 		 * FIXME: Send Unsolicited NOPIN with reserved
1157 		 * TTT here to help the initiator figure out
1158 		 * the missing CmdSN, although they should be
1159 		 * intelligent enough to determine the missing
1160 		 * CmdSN and issue a retry to plug the sequence.
1161 		 */
1162 		cmd->i_state = ISTATE_REMOVE;
1163 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1164 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1165 		return -1;
1166 
1167 	return 0;
1168 }
1169 
1170 static int
1171 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1172 			   unsigned char *buf)
1173 {
1174 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1175 	int rc, immed_data;
1176 	bool dump_payload = false;
1177 
1178 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1179 	if (rc < 0)
1180 		return 0;
1181 	/*
1182 	 * Allocation iovecs needed for struct socket operations for
1183 	 * traditional iSCSI block I/O.
1184 	 */
1185 	if (iscsit_allocate_iovecs(cmd) < 0) {
1186 		return iscsit_add_reject_cmd(cmd,
1187 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1188 	}
1189 	immed_data = cmd->immediate_data;
1190 
1191 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1192 	if (rc < 0)
1193 		return rc;
1194 	else if (rc > 0)
1195 		dump_payload = true;
1196 
1197 	if (!immed_data)
1198 		return 0;
1199 
1200 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1201 }
1202 
1203 static u32 iscsit_do_crypto_hash_sg(
1204 	struct hash_desc *hash,
1205 	struct iscsi_cmd *cmd,
1206 	u32 data_offset,
1207 	u32 data_length,
1208 	u32 padding,
1209 	u8 *pad_bytes)
1210 {
1211 	u32 data_crc;
1212 	u32 i;
1213 	struct scatterlist *sg;
1214 	unsigned int page_off;
1215 
1216 	crypto_hash_init(hash);
1217 
1218 	sg = cmd->first_data_sg;
1219 	page_off = cmd->first_data_sg_off;
1220 
1221 	i = 0;
1222 	while (data_length) {
1223 		u32 cur_len = min_t(u32, data_length, (sg[i].length - page_off));
1224 
1225 		crypto_hash_update(hash, &sg[i], cur_len);
1226 
1227 		data_length -= cur_len;
1228 		page_off = 0;
1229 		i++;
1230 	}
1231 
1232 	if (padding) {
1233 		struct scatterlist pad_sg;
1234 
1235 		sg_init_one(&pad_sg, pad_bytes, padding);
1236 		crypto_hash_update(hash, &pad_sg, padding);
1237 	}
1238 	crypto_hash_final(hash, (u8 *) &data_crc);
1239 
1240 	return data_crc;
1241 }
1242 
1243 static void iscsit_do_crypto_hash_buf(
1244 	struct hash_desc *hash,
1245 	const void *buf,
1246 	u32 payload_length,
1247 	u32 padding,
1248 	u8 *pad_bytes,
1249 	u8 *data_crc)
1250 {
1251 	struct scatterlist sg;
1252 
1253 	crypto_hash_init(hash);
1254 
1255 	sg_init_one(&sg, buf, payload_length);
1256 	crypto_hash_update(hash, &sg, payload_length);
1257 
1258 	if (padding) {
1259 		sg_init_one(&sg, pad_bytes, padding);
1260 		crypto_hash_update(hash, &sg, padding);
1261 	}
1262 	crypto_hash_final(hash, data_crc);
1263 }
1264 
1265 int
1266 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1267 			  struct iscsi_cmd **out_cmd)
1268 {
1269 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1270 	struct iscsi_cmd *cmd = NULL;
1271 	struct se_cmd *se_cmd;
1272 	u32 payload_length = ntoh24(hdr->dlength);
1273 	int rc;
1274 
1275 	if (!payload_length) {
1276 		pr_warn("DataOUT payload is ZERO, ignoring.\n");
1277 		return 0;
1278 	}
1279 
1280 	/* iSCSI write */
1281 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1282 
1283 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1284 		pr_err("DataSegmentLength: %u is greater than"
1285 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1286 			conn->conn_ops->MaxXmitDataSegmentLength);
1287 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1288 					 buf);
1289 	}
1290 
1291 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1292 			payload_length);
1293 	if (!cmd)
1294 		return 0;
1295 
1296 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1297 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1298 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1299 		payload_length, conn->cid);
1300 
1301 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1302 		pr_err("Command ITT: 0x%08x received DataOUT after"
1303 			" last DataOUT received, dumping payload\n",
1304 			cmd->init_task_tag);
1305 		return iscsit_dump_data_payload(conn, payload_length, 1);
1306 	}
1307 
1308 	if (cmd->data_direction != DMA_TO_DEVICE) {
1309 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1310 			" NON-WRITE command.\n", cmd->init_task_tag);
1311 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
1312 	}
1313 	se_cmd = &cmd->se_cmd;
1314 	iscsit_mod_dataout_timer(cmd);
1315 
1316 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1317 		pr_err("DataOut Offset: %u, Length %u greater than"
1318 			" iSCSI Command EDTL %u, protocol error.\n",
1319 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1320 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1321 	}
1322 
1323 	if (cmd->unsolicited_data) {
1324 		int dump_unsolicited_data = 0;
1325 
1326 		if (conn->sess->sess_ops->InitialR2T) {
1327 			pr_err("Received unexpected unsolicited data"
1328 				" while InitialR2T=Yes, protocol error.\n");
1329 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1330 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1331 			return -1;
1332 		}
1333 		/*
1334 		 * Special case for dealing with Unsolicited DataOUT
1335 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1336 		 * failures;
1337 		 */
1338 
1339 		/* Something's amiss if we're not in WRITE_PENDING state... */
1340 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1341 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1342 			dump_unsolicited_data = 1;
1343 
1344 		if (dump_unsolicited_data) {
1345 			/*
1346 			 * Check if a delayed TASK_ABORTED status needs to
1347 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1348 			 * received with the unsolicitied data out.
1349 			 */
1350 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1351 				iscsit_stop_dataout_timer(cmd);
1352 
1353 			transport_check_aborted_status(se_cmd,
1354 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1355 			return iscsit_dump_data_payload(conn, payload_length, 1);
1356 		}
1357 	} else {
1358 		/*
1359 		 * For the normal solicited data path:
1360 		 *
1361 		 * Check for a delayed TASK_ABORTED status and dump any
1362 		 * incoming data out payload if one exists.  Also, when the
1363 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1364 		 * data out sequence, we decrement outstanding_r2ts.  Once
1365 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1366 		 * TASK_ABORTED status.
1367 		 */
1368 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1369 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1370 				if (--cmd->outstanding_r2ts < 1) {
1371 					iscsit_stop_dataout_timer(cmd);
1372 					transport_check_aborted_status(
1373 							se_cmd, 1);
1374 				}
1375 
1376 			return iscsit_dump_data_payload(conn, payload_length, 1);
1377 		}
1378 	}
1379 	/*
1380 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1381 	 * within-command recovery checks before receiving the payload.
1382 	 */
1383 	rc = iscsit_check_pre_dataout(cmd, buf);
1384 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1385 		return 0;
1386 	else if (rc == DATAOUT_CANNOT_RECOVER)
1387 		return -1;
1388 
1389 	*out_cmd = cmd;
1390 	return 0;
1391 }
1392 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1393 
1394 static int
1395 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1396 		   struct iscsi_data *hdr)
1397 {
1398 	struct kvec *iov;
1399 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1400 	u32 payload_length = ntoh24(hdr->dlength);
1401 	int iov_ret, data_crc_failed = 0;
1402 
1403 	rx_size += payload_length;
1404 	iov = &cmd->iov_data[0];
1405 
1406 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1407 				   payload_length);
1408 	if (iov_ret < 0)
1409 		return -1;
1410 
1411 	iov_count += iov_ret;
1412 
1413 	padding = ((-payload_length) & 3);
1414 	if (padding != 0) {
1415 		iov[iov_count].iov_base	= cmd->pad_bytes;
1416 		iov[iov_count++].iov_len = padding;
1417 		rx_size += padding;
1418 		pr_debug("Receiving %u padding bytes.\n", padding);
1419 	}
1420 
1421 	if (conn->conn_ops->DataDigest) {
1422 		iov[iov_count].iov_base = &checksum;
1423 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1424 		rx_size += ISCSI_CRC_LEN;
1425 	}
1426 
1427 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1428 
1429 	iscsit_unmap_iovec(cmd);
1430 
1431 	if (rx_got != rx_size)
1432 		return -1;
1433 
1434 	if (conn->conn_ops->DataDigest) {
1435 		u32 data_crc;
1436 
1437 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
1438 						    be32_to_cpu(hdr->offset),
1439 						    payload_length, padding,
1440 						    cmd->pad_bytes);
1441 
1442 		if (checksum != data_crc) {
1443 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1444 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1445 				" does not match computed 0x%08x\n",
1446 				hdr->itt, hdr->offset, payload_length,
1447 				hdr->datasn, checksum, data_crc);
1448 			data_crc_failed = 1;
1449 		} else {
1450 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1451 				" %u bytes of Data Out\n", checksum,
1452 				payload_length);
1453 		}
1454 	}
1455 
1456 	return data_crc_failed;
1457 }
1458 
1459 int
1460 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1461 			     bool data_crc_failed)
1462 {
1463 	struct iscsi_conn *conn = cmd->conn;
1464 	int rc, ooo_cmdsn;
1465 	/*
1466 	 * Increment post receive data and CRC values or perform
1467 	 * within-command recovery.
1468 	 */
1469 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1470 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1471 		return 0;
1472 	else if (rc == DATAOUT_SEND_R2T) {
1473 		iscsit_set_dataout_sequence_values(cmd);
1474 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1475 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1476 		/*
1477 		 * Handle extra special case for out of order
1478 		 * Unsolicited Data Out.
1479 		 */
1480 		spin_lock_bh(&cmd->istate_lock);
1481 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1482 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1483 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1484 		spin_unlock_bh(&cmd->istate_lock);
1485 
1486 		iscsit_stop_dataout_timer(cmd);
1487 		if (ooo_cmdsn)
1488 			return 0;
1489 		target_execute_cmd(&cmd->se_cmd);
1490 		return 0;
1491 	} else /* DATAOUT_CANNOT_RECOVER */
1492 		return -1;
1493 
1494 	return 0;
1495 }
1496 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1497 
1498 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1499 {
1500 	struct iscsi_cmd *cmd = NULL;
1501 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1502 	int rc;
1503 	bool data_crc_failed = false;
1504 
1505 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1506 	if (rc < 0)
1507 		return 0;
1508 	else if (!cmd)
1509 		return 0;
1510 
1511 	rc = iscsit_get_dataout(conn, cmd, hdr);
1512 	if (rc < 0)
1513 		return rc;
1514 	else if (rc > 0)
1515 		data_crc_failed = true;
1516 
1517 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1518 }
1519 
1520 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1521 			 struct iscsi_nopout *hdr)
1522 {
1523 	u32 payload_length = ntoh24(hdr->dlength);
1524 
1525 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1526 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1527 		if (!cmd)
1528 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1529 						 (unsigned char *)hdr);
1530 
1531 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1532 					 (unsigned char *)hdr);
1533 	}
1534 
1535 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1536 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1537 			" not set, protocol error.\n");
1538 		if (!cmd)
1539 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1540 						 (unsigned char *)hdr);
1541 
1542 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1543 					 (unsigned char *)hdr);
1544 	}
1545 
1546 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1547 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1548 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1549 			" error.\n", payload_length,
1550 			conn->conn_ops->MaxXmitDataSegmentLength);
1551 		if (!cmd)
1552 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1553 						 (unsigned char *)hdr);
1554 
1555 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1556 					 (unsigned char *)hdr);
1557 	}
1558 
1559 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1560 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1561 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1562 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1563 		payload_length);
1564 	/*
1565 	 * This is not a response to a Unsolicited NopIN, which means
1566 	 * it can either be a NOPOUT ping request (with a valid ITT),
1567 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1568 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1569 	 * can contain ping data.
1570 	 */
1571 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1572 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1573 		cmd->i_state		= ISTATE_SEND_NOPIN;
1574 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1575 						1 : 0);
1576 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1577 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1578 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1579 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1580 		cmd->data_direction	= DMA_NONE;
1581 	}
1582 
1583 	return 0;
1584 }
1585 EXPORT_SYMBOL(iscsit_setup_nop_out);
1586 
1587 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1588 			   struct iscsi_nopout *hdr)
1589 {
1590 	struct iscsi_cmd *cmd_p = NULL;
1591 	int cmdsn_ret = 0;
1592 	/*
1593 	 * Initiator is expecting a NopIN ping reply..
1594 	 */
1595 	if (hdr->itt != RESERVED_ITT) {
1596 		if (!cmd)
1597 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1598 						(unsigned char *)hdr);
1599 
1600 		spin_lock_bh(&conn->cmd_lock);
1601 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1602 		spin_unlock_bh(&conn->cmd_lock);
1603 
1604 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1605 
1606 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1607 			iscsit_add_cmd_to_response_queue(cmd, conn,
1608 							 cmd->i_state);
1609 			return 0;
1610 		}
1611 
1612 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1613 				(unsigned char *)hdr, hdr->cmdsn);
1614                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1615 			return 0;
1616 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1617 			return -1;
1618 
1619 		return 0;
1620 	}
1621 	/*
1622 	 * This was a response to a unsolicited NOPIN ping.
1623 	 */
1624 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1625 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1626 		if (!cmd_p)
1627 			return -EINVAL;
1628 
1629 		iscsit_stop_nopin_response_timer(conn);
1630 
1631 		cmd_p->i_state = ISTATE_REMOVE;
1632 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1633 
1634 		iscsit_start_nopin_timer(conn);
1635 		return 0;
1636 	}
1637 	/*
1638 	 * Otherwise, initiator is not expecting a NOPIN is response.
1639 	 * Just ignore for now.
1640 	 */
1641         return 0;
1642 }
1643 EXPORT_SYMBOL(iscsit_process_nop_out);
1644 
1645 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1646 				 unsigned char *buf)
1647 {
1648 	unsigned char *ping_data = NULL;
1649 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1650 	struct kvec *iov = NULL;
1651 	u32 payload_length = ntoh24(hdr->dlength);
1652 	int ret;
1653 
1654 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1655 	if (ret < 0)
1656 		return 0;
1657 	/*
1658 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1659 	 */
1660 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1661 		u32 checksum, data_crc, padding = 0;
1662 		int niov = 0, rx_got, rx_size = payload_length;
1663 
1664 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1665 		if (!ping_data) {
1666 			pr_err("Unable to allocate memory for"
1667 				" NOPOUT ping data.\n");
1668 			ret = -1;
1669 			goto out;
1670 		}
1671 
1672 		iov = &cmd->iov_misc[0];
1673 		iov[niov].iov_base	= ping_data;
1674 		iov[niov++].iov_len	= payload_length;
1675 
1676 		padding = ((-payload_length) & 3);
1677 		if (padding != 0) {
1678 			pr_debug("Receiving %u additional bytes"
1679 				" for padding.\n", padding);
1680 			iov[niov].iov_base	= &cmd->pad_bytes;
1681 			iov[niov++].iov_len	= padding;
1682 			rx_size += padding;
1683 		}
1684 		if (conn->conn_ops->DataDigest) {
1685 			iov[niov].iov_base	= &checksum;
1686 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1687 			rx_size += ISCSI_CRC_LEN;
1688 		}
1689 
1690 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1691 		if (rx_got != rx_size) {
1692 			ret = -1;
1693 			goto out;
1694 		}
1695 
1696 		if (conn->conn_ops->DataDigest) {
1697 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
1698 					ping_data, payload_length,
1699 					padding, cmd->pad_bytes,
1700 					(u8 *)&data_crc);
1701 
1702 			if (checksum != data_crc) {
1703 				pr_err("Ping data CRC32C DataDigest"
1704 				" 0x%08x does not match computed 0x%08x\n",
1705 					checksum, data_crc);
1706 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1707 					pr_err("Unable to recover from"
1708 					" NOPOUT Ping DataCRC failure while in"
1709 						" ERL=0.\n");
1710 					ret = -1;
1711 					goto out;
1712 				} else {
1713 					/*
1714 					 * Silently drop this PDU and let the
1715 					 * initiator plug the CmdSN gap.
1716 					 */
1717 					pr_debug("Dropping NOPOUT"
1718 					" Command CmdSN: 0x%08x due to"
1719 					" DataCRC error.\n", hdr->cmdsn);
1720 					ret = 0;
1721 					goto out;
1722 				}
1723 			} else {
1724 				pr_debug("Got CRC32C DataDigest"
1725 				" 0x%08x for %u bytes of ping data.\n",
1726 					checksum, payload_length);
1727 			}
1728 		}
1729 
1730 		ping_data[payload_length] = '\0';
1731 		/*
1732 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1733 		 */
1734 		cmd->buf_ptr = ping_data;
1735 		cmd->buf_ptr_size = payload_length;
1736 
1737 		pr_debug("Got %u bytes of NOPOUT ping"
1738 			" data.\n", payload_length);
1739 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1740 	}
1741 
1742 	return iscsit_process_nop_out(conn, cmd, hdr);
1743 out:
1744 	if (cmd)
1745 		iscsit_free_cmd(cmd, false);
1746 
1747 	kfree(ping_data);
1748 	return ret;
1749 }
1750 
1751 int
1752 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1753 			   unsigned char *buf)
1754 {
1755 	struct se_tmr_req *se_tmr;
1756 	struct iscsi_tmr_req *tmr_req;
1757 	struct iscsi_tm *hdr;
1758 	int out_of_order_cmdsn = 0, ret;
1759 	bool sess_ref = false;
1760 	u8 function;
1761 
1762 	hdr			= (struct iscsi_tm *) buf;
1763 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1764 	function = hdr->flags;
1765 
1766 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1767 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1768 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1769 		hdr->rtt, hdr->refcmdsn, conn->cid);
1770 
1771 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1772 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1773 	     hdr->rtt != RESERVED_ITT)) {
1774 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1775 		hdr->rtt = RESERVED_ITT;
1776 	}
1777 
1778 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1779 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1780 		pr_err("Task Management Request TASK_REASSIGN not"
1781 			" issued as immediate command, bad iSCSI Initiator"
1782 				"implementation\n");
1783 		return iscsit_add_reject_cmd(cmd,
1784 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1785 	}
1786 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1787 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1788 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1789 
1790 	cmd->data_direction = DMA_NONE;
1791 
1792 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1793 	if (!cmd->tmr_req) {
1794 		pr_err("Unable to allocate memory for"
1795 			" Task Management command!\n");
1796 		return iscsit_add_reject_cmd(cmd,
1797 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1798 					     buf);
1799 	}
1800 
1801 	/*
1802 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1803 	 * LIO-Target $FABRIC_MOD
1804 	 */
1805 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1806 
1807 		u8 tcm_function;
1808 		int ret;
1809 
1810 		transport_init_se_cmd(&cmd->se_cmd,
1811 				      &lio_target_fabric_configfs->tf_ops,
1812 				      conn->sess->se_sess, 0, DMA_NONE,
1813 				      MSG_SIMPLE_TAG, cmd->sense_buffer + 2);
1814 
1815 		target_get_sess_cmd(conn->sess->se_sess, &cmd->se_cmd, true);
1816 		sess_ref = true;
1817 
1818 		switch (function) {
1819 		case ISCSI_TM_FUNC_ABORT_TASK:
1820 			tcm_function = TMR_ABORT_TASK;
1821 			break;
1822 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1823 			tcm_function = TMR_ABORT_TASK_SET;
1824 			break;
1825 		case ISCSI_TM_FUNC_CLEAR_ACA:
1826 			tcm_function = TMR_CLEAR_ACA;
1827 			break;
1828 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1829 			tcm_function = TMR_CLEAR_TASK_SET;
1830 			break;
1831 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1832 			tcm_function = TMR_LUN_RESET;
1833 			break;
1834 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1835 			tcm_function = TMR_TARGET_WARM_RESET;
1836 			break;
1837 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1838 			tcm_function = TMR_TARGET_COLD_RESET;
1839 			break;
1840 		default:
1841 			pr_err("Unknown iSCSI TMR Function:"
1842 			       " 0x%02x\n", function);
1843 			return iscsit_add_reject_cmd(cmd,
1844 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1845 		}
1846 
1847 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
1848 					 tcm_function, GFP_KERNEL);
1849 		if (ret < 0)
1850 			return iscsit_add_reject_cmd(cmd,
1851 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1852 
1853 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
1854 	}
1855 
1856 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
1857 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
1858 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1859 	cmd->init_task_tag	= hdr->itt;
1860 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1861 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1862 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1863 	se_tmr			= cmd->se_cmd.se_tmr_req;
1864 	tmr_req			= cmd->tmr_req;
1865 	/*
1866 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
1867 	 */
1868 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1869 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
1870 					       scsilun_to_int(&hdr->lun));
1871 		if (ret < 0) {
1872 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
1873 			goto attach;
1874 		}
1875 	}
1876 
1877 	switch (function) {
1878 	case ISCSI_TM_FUNC_ABORT_TASK:
1879 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
1880 		if (se_tmr->response)
1881 			goto attach;
1882 		break;
1883 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1884 	case ISCSI_TM_FUNC_CLEAR_ACA:
1885 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1886 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1887 		break;
1888 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1889 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
1890 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1891 			goto attach;
1892 		}
1893 		break;
1894 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1895 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
1896 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
1897 			goto attach;
1898 		}
1899 		break;
1900 	case ISCSI_TM_FUNC_TASK_REASSIGN:
1901 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
1902 		/*
1903 		 * Perform sanity checks on the ExpDataSN only if the
1904 		 * TASK_REASSIGN was successful.
1905 		 */
1906 		if (se_tmr->response)
1907 			break;
1908 
1909 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
1910 			return iscsit_add_reject_cmd(cmd,
1911 					ISCSI_REASON_BOOKMARK_INVALID, buf);
1912 		break;
1913 	default:
1914 		pr_err("Unknown TMR function: 0x%02x, protocol"
1915 			" error.\n", function);
1916 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
1917 		goto attach;
1918 	}
1919 
1920 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1921 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
1922 		se_tmr->call_transport = 1;
1923 attach:
1924 	spin_lock_bh(&conn->cmd_lock);
1925 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1926 	spin_unlock_bh(&conn->cmd_lock);
1927 
1928 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1929 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
1930 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
1931 			out_of_order_cmdsn = 1;
1932 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1933 			return 0;
1934 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1935 			return -1;
1936 	}
1937 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1938 
1939 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
1940 		return 0;
1941 	/*
1942 	 * Found the referenced task, send to transport for processing.
1943 	 */
1944 	if (se_tmr->call_transport)
1945 		return transport_generic_handle_tmr(&cmd->se_cmd);
1946 
1947 	/*
1948 	 * Could not find the referenced LUN, task, or Task Management
1949 	 * command not authorized or supported.  Change state and
1950 	 * let the tx_thread send the response.
1951 	 *
1952 	 * For connection recovery, this is also the default action for
1953 	 * TMR TASK_REASSIGN.
1954 	 */
1955 	if (sess_ref) {
1956 		pr_debug("Handle TMR, using sess_ref=true check\n");
1957 		target_put_sess_cmd(conn->sess->se_sess, &cmd->se_cmd);
1958 	}
1959 
1960 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
1961 	return 0;
1962 }
1963 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
1964 
1965 /* #warning FIXME: Support Text Command parameters besides SendTargets */
1966 int
1967 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1968 		      struct iscsi_text *hdr)
1969 {
1970 	u32 payload_length = ntoh24(hdr->dlength);
1971 
1972 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1973 		pr_err("Unable to accept text parameter length: %u"
1974 			"greater than MaxXmitDataSegmentLength %u.\n",
1975 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1976 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1977 					 (unsigned char *)hdr);
1978 	}
1979 
1980 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
1981 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
1982 		pr_err("Multi sequence text commands currently not supported\n");
1983 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
1984 					(unsigned char *)hdr);
1985 	}
1986 
1987 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
1988 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
1989 		hdr->exp_statsn, payload_length);
1990 
1991 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
1992 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
1993 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1994 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
1995 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
1996 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1997 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1998 	cmd->data_direction	= DMA_NONE;
1999 
2000 	return 0;
2001 }
2002 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2003 
2004 int
2005 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2006 			struct iscsi_text *hdr)
2007 {
2008 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2009 	int cmdsn_ret;
2010 
2011 	if (!text_in) {
2012 		pr_err("Unable to locate text_in buffer for sendtargets"
2013 		       " discovery\n");
2014 		goto reject;
2015 	}
2016 	if (strncmp("SendTargets", text_in, 11) != 0) {
2017 		pr_err("Received Text Data that is not"
2018 			" SendTargets, cannot continue.\n");
2019 		goto reject;
2020 	}
2021 	text_ptr = strchr(text_in, '=');
2022 	if (!text_ptr) {
2023 		pr_err("No \"=\" separator found in Text Data,"
2024 			"  cannot continue.\n");
2025 		goto reject;
2026 	}
2027 	if (!strncmp("=All", text_ptr, 4)) {
2028 		cmd->cmd_flags |= IFC_SENDTARGETS_ALL;
2029 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2030 		   !strncmp("=eui.", text_ptr, 5)) {
2031 		cmd->cmd_flags |= IFC_SENDTARGETS_SINGLE;
2032 	} else {
2033 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2034 		goto reject;
2035 	}
2036 
2037 	spin_lock_bh(&conn->cmd_lock);
2038 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2039 	spin_unlock_bh(&conn->cmd_lock);
2040 
2041 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2042 
2043 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2044 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2045 				(unsigned char *)hdr, hdr->cmdsn);
2046 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2047 			return -1;
2048 
2049 		return 0;
2050 	}
2051 
2052 	return iscsit_execute_cmd(cmd, 0);
2053 
2054 reject:
2055 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2056 				 (unsigned char *)hdr);
2057 }
2058 EXPORT_SYMBOL(iscsit_process_text_cmd);
2059 
2060 static int
2061 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2062 		       unsigned char *buf)
2063 {
2064 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2065 	char *text_in = NULL;
2066 	u32 payload_length = ntoh24(hdr->dlength);
2067 	int rx_size, rc;
2068 
2069 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2070 	if (rc < 0)
2071 		return 0;
2072 
2073 	rx_size = payload_length;
2074 	if (payload_length) {
2075 		u32 checksum = 0, data_crc = 0;
2076 		u32 padding = 0, pad_bytes = 0;
2077 		int niov = 0, rx_got;
2078 		struct kvec iov[3];
2079 
2080 		text_in = kzalloc(payload_length, GFP_KERNEL);
2081 		if (!text_in) {
2082 			pr_err("Unable to allocate memory for"
2083 				" incoming text parameters\n");
2084 			goto reject;
2085 		}
2086 		cmd->text_in_ptr = text_in;
2087 
2088 		memset(iov, 0, 3 * sizeof(struct kvec));
2089 		iov[niov].iov_base	= text_in;
2090 		iov[niov++].iov_len	= payload_length;
2091 
2092 		padding = ((-payload_length) & 3);
2093 		if (padding != 0) {
2094 			iov[niov].iov_base = &pad_bytes;
2095 			iov[niov++].iov_len  = padding;
2096 			rx_size += padding;
2097 			pr_debug("Receiving %u additional bytes"
2098 					" for padding.\n", padding);
2099 		}
2100 		if (conn->conn_ops->DataDigest) {
2101 			iov[niov].iov_base	= &checksum;
2102 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2103 			rx_size += ISCSI_CRC_LEN;
2104 		}
2105 
2106 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2107 		if (rx_got != rx_size)
2108 			goto reject;
2109 
2110 		if (conn->conn_ops->DataDigest) {
2111 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
2112 					text_in, payload_length,
2113 					padding, (u8 *)&pad_bytes,
2114 					(u8 *)&data_crc);
2115 
2116 			if (checksum != data_crc) {
2117 				pr_err("Text data CRC32C DataDigest"
2118 					" 0x%08x does not match computed"
2119 					" 0x%08x\n", checksum, data_crc);
2120 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2121 					pr_err("Unable to recover from"
2122 					" Text Data digest failure while in"
2123 						" ERL=0.\n");
2124 					goto reject;
2125 				} else {
2126 					/*
2127 					 * Silently drop this PDU and let the
2128 					 * initiator plug the CmdSN gap.
2129 					 */
2130 					pr_debug("Dropping Text"
2131 					" Command CmdSN: 0x%08x due to"
2132 					" DataCRC error.\n", hdr->cmdsn);
2133 					kfree(text_in);
2134 					return 0;
2135 				}
2136 			} else {
2137 				pr_debug("Got CRC32C DataDigest"
2138 					" 0x%08x for %u bytes of text data.\n",
2139 						checksum, payload_length);
2140 			}
2141 		}
2142 		text_in[payload_length - 1] = '\0';
2143 		pr_debug("Successfully read %d bytes of text"
2144 				" data.\n", payload_length);
2145 	}
2146 
2147 	return iscsit_process_text_cmd(conn, cmd, hdr);
2148 
2149 reject:
2150 	kfree(cmd->text_in_ptr);
2151 	cmd->text_in_ptr = NULL;
2152 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2153 }
2154 EXPORT_SYMBOL(iscsit_handle_text_cmd);
2155 
2156 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2157 {
2158 	struct iscsi_conn *conn_p;
2159 	struct iscsi_session *sess = conn->sess;
2160 
2161 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2162 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2163 
2164 	atomic_set(&sess->session_logout, 1);
2165 	atomic_set(&conn->conn_logout_remove, 1);
2166 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2167 
2168 	iscsit_inc_conn_usage_count(conn);
2169 	iscsit_inc_session_usage_count(sess);
2170 
2171 	spin_lock_bh(&sess->conn_lock);
2172 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2173 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2174 			continue;
2175 
2176 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2177 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2178 	}
2179 	spin_unlock_bh(&sess->conn_lock);
2180 
2181 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2182 
2183 	return 0;
2184 }
2185 
2186 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2187 {
2188 	struct iscsi_conn *l_conn;
2189 	struct iscsi_session *sess = conn->sess;
2190 
2191 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2192 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2193 
2194 	/*
2195 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2196 	 * can arrive on a connection with a differing CID.
2197 	 */
2198 	if (conn->cid == cmd->logout_cid) {
2199 		spin_lock_bh(&conn->state_lock);
2200 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2201 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2202 
2203 		atomic_set(&conn->conn_logout_remove, 1);
2204 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2205 		iscsit_inc_conn_usage_count(conn);
2206 
2207 		spin_unlock_bh(&conn->state_lock);
2208 	} else {
2209 		/*
2210 		 * Handle all different cid CLOSECONNECTION requests in
2211 		 * iscsit_logout_post_handler_diffcid() as to give enough
2212 		 * time for any non immediate command's CmdSN to be
2213 		 * acknowledged on the connection in question.
2214 		 *
2215 		 * Here we simply make sure the CID is still around.
2216 		 */
2217 		l_conn = iscsit_get_conn_from_cid(sess,
2218 				cmd->logout_cid);
2219 		if (!l_conn) {
2220 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2221 			iscsit_add_cmd_to_response_queue(cmd, conn,
2222 					cmd->i_state);
2223 			return 0;
2224 		}
2225 
2226 		iscsit_dec_conn_usage_count(l_conn);
2227 	}
2228 
2229 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2230 
2231 	return 0;
2232 }
2233 
2234 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2235 {
2236 	struct iscsi_session *sess = conn->sess;
2237 
2238 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2239 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2240 
2241 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2242 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2243 			" while ERL!=2.\n");
2244 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2245 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2246 		return 0;
2247 	}
2248 
2249 	if (conn->cid == cmd->logout_cid) {
2250 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2251 			" with CID: %hu on CID: %hu, implementation error.\n",
2252 				cmd->logout_cid, conn->cid);
2253 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2254 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2255 		return 0;
2256 	}
2257 
2258 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2259 
2260 	return 0;
2261 }
2262 
2263 int
2264 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2265 			unsigned char *buf)
2266 {
2267 	int cmdsn_ret, logout_remove = 0;
2268 	u8 reason_code = 0;
2269 	struct iscsi_logout *hdr;
2270 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2271 
2272 	hdr			= (struct iscsi_logout *) buf;
2273 	reason_code		= (hdr->flags & 0x7f);
2274 
2275 	if (tiqn) {
2276 		spin_lock(&tiqn->logout_stats.lock);
2277 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2278 			tiqn->logout_stats.normal_logouts++;
2279 		else
2280 			tiqn->logout_stats.abnormal_logouts++;
2281 		spin_unlock(&tiqn->logout_stats.lock);
2282 	}
2283 
2284 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2285 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2286 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2287 		hdr->cid, conn->cid);
2288 
2289 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2290 		pr_err("Received logout request on connection that"
2291 			" is not in logged in state, ignoring request.\n");
2292 		iscsit_free_cmd(cmd, false);
2293 		return 0;
2294 	}
2295 
2296 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2297 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2298 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2299 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2300 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2301 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2302 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2303 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2304 	cmd->logout_reason      = reason_code;
2305 	cmd->data_direction     = DMA_NONE;
2306 
2307 	/*
2308 	 * We need to sleep in these cases (by returning 1) until the Logout
2309 	 * Response gets sent in the tx thread.
2310 	 */
2311 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2312 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2313 	    be16_to_cpu(hdr->cid) == conn->cid))
2314 		logout_remove = 1;
2315 
2316 	spin_lock_bh(&conn->cmd_lock);
2317 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2318 	spin_unlock_bh(&conn->cmd_lock);
2319 
2320 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2321 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2322 
2323 	/*
2324 	 * Immediate commands are executed, well, immediately.
2325 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2326 	 */
2327 	if (cmd->immediate_cmd) {
2328 		int ret = iscsit_execute_cmd(cmd, 0);
2329 
2330 		if (ret < 0)
2331 			return ret;
2332 	} else {
2333 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2334 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2335 			logout_remove = 0;
2336 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2337 			return -1;
2338 	}
2339 
2340 	return logout_remove;
2341 }
2342 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2343 
2344 static int iscsit_handle_snack(
2345 	struct iscsi_conn *conn,
2346 	unsigned char *buf)
2347 {
2348 	struct iscsi_snack *hdr;
2349 
2350 	hdr			= (struct iscsi_snack *) buf;
2351 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2352 
2353 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2354 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2355 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2356 			hdr->begrun, hdr->runlength, conn->cid);
2357 
2358 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2359 		pr_err("Initiator sent SNACK request while in"
2360 			" ErrorRecoveryLevel=0.\n");
2361 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2362 					 buf);
2363 	}
2364 	/*
2365 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2366 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2367 	 */
2368 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2369 	case 0:
2370 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2371 			hdr->itt,
2372 			be32_to_cpu(hdr->ttt),
2373 			be32_to_cpu(hdr->begrun),
2374 			be32_to_cpu(hdr->runlength));
2375 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2376 		return iscsit_handle_status_snack(conn, hdr->itt,
2377 			be32_to_cpu(hdr->ttt),
2378 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2379 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2380 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2381 			be32_to_cpu(hdr->begrun),
2382 			be32_to_cpu(hdr->runlength));
2383 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2384 		/* FIXME: Support R-Data SNACK */
2385 		pr_err("R-Data SNACK Not Supported.\n");
2386 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2387 					 buf);
2388 	default:
2389 		pr_err("Unknown SNACK type 0x%02x, protocol"
2390 			" error.\n", hdr->flags & 0x0f);
2391 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2392 					 buf);
2393 	}
2394 
2395 	return 0;
2396 }
2397 
2398 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2399 {
2400 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2401 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2402 		wait_for_completion_interruptible_timeout(
2403 					&conn->rx_half_close_comp,
2404 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2405 	}
2406 }
2407 
2408 static int iscsit_handle_immediate_data(
2409 	struct iscsi_cmd *cmd,
2410 	struct iscsi_scsi_req *hdr,
2411 	u32 length)
2412 {
2413 	int iov_ret, rx_got = 0, rx_size = 0;
2414 	u32 checksum, iov_count = 0, padding = 0;
2415 	struct iscsi_conn *conn = cmd->conn;
2416 	struct kvec *iov;
2417 
2418 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2419 	if (iov_ret < 0)
2420 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2421 
2422 	rx_size = length;
2423 	iov_count = iov_ret;
2424 	iov = &cmd->iov_data[0];
2425 
2426 	padding = ((-length) & 3);
2427 	if (padding != 0) {
2428 		iov[iov_count].iov_base	= cmd->pad_bytes;
2429 		iov[iov_count++].iov_len = padding;
2430 		rx_size += padding;
2431 	}
2432 
2433 	if (conn->conn_ops->DataDigest) {
2434 		iov[iov_count].iov_base		= &checksum;
2435 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2436 		rx_size += ISCSI_CRC_LEN;
2437 	}
2438 
2439 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2440 
2441 	iscsit_unmap_iovec(cmd);
2442 
2443 	if (rx_got != rx_size) {
2444 		iscsit_rx_thread_wait_for_tcp(conn);
2445 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2446 	}
2447 
2448 	if (conn->conn_ops->DataDigest) {
2449 		u32 data_crc;
2450 
2451 		data_crc = iscsit_do_crypto_hash_sg(&conn->conn_rx_hash, cmd,
2452 						    cmd->write_data_done, length, padding,
2453 						    cmd->pad_bytes);
2454 
2455 		if (checksum != data_crc) {
2456 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2457 				" does not match computed 0x%08x\n", checksum,
2458 				data_crc);
2459 
2460 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2461 				pr_err("Unable to recover from"
2462 					" Immediate Data digest failure while"
2463 					" in ERL=0.\n");
2464 				iscsit_reject_cmd(cmd,
2465 						ISCSI_REASON_DATA_DIGEST_ERROR,
2466 						(unsigned char *)hdr);
2467 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2468 			} else {
2469 				iscsit_reject_cmd(cmd,
2470 						ISCSI_REASON_DATA_DIGEST_ERROR,
2471 						(unsigned char *)hdr);
2472 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2473 			}
2474 		} else {
2475 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2476 				" %u bytes of Immediate Data\n", checksum,
2477 				length);
2478 		}
2479 	}
2480 
2481 	cmd->write_data_done += length;
2482 
2483 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2484 		spin_lock_bh(&cmd->istate_lock);
2485 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2486 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2487 		spin_unlock_bh(&cmd->istate_lock);
2488 	}
2489 
2490 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2491 }
2492 
2493 /*
2494  *	Called with sess->conn_lock held.
2495  */
2496 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2497 	with active network interface */
2498 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2499 {
2500 	struct iscsi_cmd *cmd;
2501 	struct iscsi_conn *conn_p;
2502 	bool found = false;
2503 
2504 	/*
2505 	 * Only send a Asynchronous Message on connections whos network
2506 	 * interface is still functional.
2507 	 */
2508 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2509 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2510 			iscsit_inc_conn_usage_count(conn_p);
2511 			found = true;
2512 			break;
2513 		}
2514 	}
2515 
2516 	if (!found)
2517 		return;
2518 
2519 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2520 	if (!cmd) {
2521 		iscsit_dec_conn_usage_count(conn_p);
2522 		return;
2523 	}
2524 
2525 	cmd->logout_cid = conn->cid;
2526 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2527 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2528 
2529 	spin_lock_bh(&conn_p->cmd_lock);
2530 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2531 	spin_unlock_bh(&conn_p->cmd_lock);
2532 
2533 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2534 	iscsit_dec_conn_usage_count(conn_p);
2535 }
2536 
2537 static int iscsit_send_conn_drop_async_message(
2538 	struct iscsi_cmd *cmd,
2539 	struct iscsi_conn *conn)
2540 {
2541 	struct iscsi_async *hdr;
2542 
2543 	cmd->tx_size = ISCSI_HDR_LEN;
2544 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2545 
2546 	hdr			= (struct iscsi_async *) cmd->pdu;
2547 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2548 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2549 	cmd->init_task_tag	= RESERVED_ITT;
2550 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2551 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2552 	cmd->stat_sn		= conn->stat_sn++;
2553 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2554 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2555 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2556 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2557 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2558 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2559 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2560 
2561 	if (conn->conn_ops->HeaderDigest) {
2562 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2563 
2564 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2565 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2566 
2567 		cmd->tx_size += ISCSI_CRC_LEN;
2568 		pr_debug("Attaching CRC32C HeaderDigest to"
2569 			" Async Message 0x%08x\n", *header_digest);
2570 	}
2571 
2572 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2573 	cmd->iov_misc[0].iov_len	= cmd->tx_size;
2574 	cmd->iov_misc_count		= 1;
2575 
2576 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2577 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2578 			cmd->logout_cid, conn->cid);
2579 	return 0;
2580 }
2581 
2582 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2583 {
2584 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2585 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2586 		wait_for_completion_interruptible_timeout(
2587 					&conn->tx_half_close_comp,
2588 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2589 	}
2590 }
2591 
2592 static void
2593 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2594 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2595 			bool set_statsn)
2596 {
2597 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2598 	hdr->flags		= datain->flags;
2599 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2600 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2601 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2602 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2603 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2604 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2605 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2606 		}
2607 	}
2608 	hton24(hdr->dlength, datain->length);
2609 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2610 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2611 				(struct scsi_lun *)&hdr->lun);
2612 	else
2613 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2614 
2615 	hdr->itt		= cmd->init_task_tag;
2616 
2617 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2618 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2619 	else
2620 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2621 	if (set_statsn)
2622 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2623 	else
2624 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2625 
2626 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2627 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2628 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2629 	hdr->offset		= cpu_to_be32(datain->offset);
2630 
2631 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2632 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2633 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2634 		ntohl(hdr->offset), datain->length, conn->cid);
2635 }
2636 
2637 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2638 {
2639 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2640 	struct iscsi_datain datain;
2641 	struct iscsi_datain_req *dr;
2642 	struct kvec *iov;
2643 	u32 iov_count = 0, tx_size = 0;
2644 	int eodr = 0, ret, iov_ret;
2645 	bool set_statsn = false;
2646 
2647 	memset(&datain, 0, sizeof(struct iscsi_datain));
2648 	dr = iscsit_get_datain_values(cmd, &datain);
2649 	if (!dr) {
2650 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2651 				cmd->init_task_tag);
2652 		return -1;
2653 	}
2654 	/*
2655 	 * Be paranoid and double check the logic for now.
2656 	 */
2657 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2658 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2659 			" datain.length: %u exceeds cmd->data_length: %u\n",
2660 			cmd->init_task_tag, datain.offset, datain.length,
2661 			cmd->se_cmd.data_length);
2662 		return -1;
2663 	}
2664 
2665 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2666 	/*
2667 	 * Special case for successfully execution w/ both DATAIN
2668 	 * and Sense Data.
2669 	 */
2670 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2671 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2672 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2673 	else {
2674 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2675 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2676 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2677 			cmd->stat_sn = conn->stat_sn++;
2678 			set_statsn = true;
2679 		} else if (dr->dr_complete ==
2680 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2681 			set_statsn = true;
2682 	}
2683 
2684 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2685 
2686 	iov = &cmd->iov_data[0];
2687 	iov[iov_count].iov_base	= cmd->pdu;
2688 	iov[iov_count++].iov_len	= ISCSI_HDR_LEN;
2689 	tx_size += ISCSI_HDR_LEN;
2690 
2691 	if (conn->conn_ops->HeaderDigest) {
2692 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2693 
2694 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
2695 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2696 
2697 		iov[0].iov_len += ISCSI_CRC_LEN;
2698 		tx_size += ISCSI_CRC_LEN;
2699 
2700 		pr_debug("Attaching CRC32 HeaderDigest"
2701 			" for DataIN PDU 0x%08x\n", *header_digest);
2702 	}
2703 
2704 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
2705 				datain.offset, datain.length);
2706 	if (iov_ret < 0)
2707 		return -1;
2708 
2709 	iov_count += iov_ret;
2710 	tx_size += datain.length;
2711 
2712 	cmd->padding = ((-datain.length) & 3);
2713 	if (cmd->padding) {
2714 		iov[iov_count].iov_base		= cmd->pad_bytes;
2715 		iov[iov_count++].iov_len	= cmd->padding;
2716 		tx_size += cmd->padding;
2717 
2718 		pr_debug("Attaching %u padding bytes\n",
2719 				cmd->padding);
2720 	}
2721 	if (conn->conn_ops->DataDigest) {
2722 		cmd->data_crc = iscsit_do_crypto_hash_sg(&conn->conn_tx_hash, cmd,
2723 			 datain.offset, datain.length, cmd->padding, cmd->pad_bytes);
2724 
2725 		iov[iov_count].iov_base	= &cmd->data_crc;
2726 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
2727 		tx_size += ISCSI_CRC_LEN;
2728 
2729 		pr_debug("Attached CRC32C DataDigest %d bytes, crc"
2730 			" 0x%08x\n", datain.length+cmd->padding, cmd->data_crc);
2731 	}
2732 
2733 	cmd->iov_data_count = iov_count;
2734 	cmd->tx_size = tx_size;
2735 
2736 	/* sendpage is preferred but can't insert markers */
2737 	if (!conn->conn_ops->IFMarker)
2738 		ret = iscsit_fe_sendpage_sg(cmd, conn);
2739 	else
2740 		ret = iscsit_send_tx_data(cmd, conn, 0);
2741 
2742 	iscsit_unmap_iovec(cmd);
2743 
2744 	if (ret < 0) {
2745 		iscsit_tx_thread_wait_for_tcp(conn);
2746 		return ret;
2747 	}
2748 
2749 	if (dr->dr_complete) {
2750 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2751 				2 : 1;
2752 		iscsit_free_datain_req(cmd, dr);
2753 	}
2754 
2755 	return eodr;
2756 }
2757 
2758 int
2759 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2760 			struct iscsi_logout_rsp *hdr)
2761 {
2762 	struct iscsi_conn *logout_conn = NULL;
2763 	struct iscsi_conn_recovery *cr = NULL;
2764 	struct iscsi_session *sess = conn->sess;
2765 	/*
2766 	 * The actual shutting down of Sessions and/or Connections
2767 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2768 	 * is done in scsi_logout_post_handler().
2769 	 */
2770 	switch (cmd->logout_reason) {
2771 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2772 		pr_debug("iSCSI session logout successful, setting"
2773 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2774 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2775 		break;
2776 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2777 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2778 			break;
2779 		/*
2780 		 * For CLOSECONNECTION logout requests carrying
2781 		 * a matching logout CID -> local CID, the reference
2782 		 * for the local CID will have been incremented in
2783 		 * iscsi_logout_closeconnection().
2784 		 *
2785 		 * For CLOSECONNECTION logout requests carrying
2786 		 * a different CID than the connection it arrived
2787 		 * on, the connection responding to cmd->logout_cid
2788 		 * is stopped in iscsit_logout_post_handler_diffcid().
2789 		 */
2790 
2791 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2792 			" successful.\n", cmd->logout_cid, conn->cid);
2793 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2794 		break;
2795 	case ISCSI_LOGOUT_REASON_RECOVERY:
2796 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2797 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2798 			break;
2799 		/*
2800 		 * If the connection is still active from our point of view
2801 		 * force connection recovery to occur.
2802 		 */
2803 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2804 				cmd->logout_cid);
2805 		if (logout_conn) {
2806 			iscsit_connection_reinstatement_rcfr(logout_conn);
2807 			iscsit_dec_conn_usage_count(logout_conn);
2808 		}
2809 
2810 		cr = iscsit_get_inactive_connection_recovery_entry(
2811 				conn->sess, cmd->logout_cid);
2812 		if (!cr) {
2813 			pr_err("Unable to locate CID: %hu for"
2814 			" REMOVECONNFORRECOVERY Logout Request.\n",
2815 				cmd->logout_cid);
2816 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2817 			break;
2818 		}
2819 
2820 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2821 
2822 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2823 			" for recovery for CID: %hu on CID: %hu successful.\n",
2824 				cmd->logout_cid, conn->cid);
2825 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2826 		break;
2827 	default:
2828 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2829 				cmd->logout_reason);
2830 		return -1;
2831 	}
2832 
2833 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2834 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2835 	hdr->response		= cmd->logout_response;
2836 	hdr->itt		= cmd->init_task_tag;
2837 	cmd->stat_sn		= conn->stat_sn++;
2838 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2839 
2840 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2841 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2842 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2843 
2844 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2845 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2846 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2847 		cmd->logout_cid, conn->cid);
2848 
2849 	return 0;
2850 }
2851 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2852 
2853 static int
2854 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2855 {
2856 	struct kvec *iov;
2857 	int niov = 0, tx_size, rc;
2858 
2859 	rc = iscsit_build_logout_rsp(cmd, conn,
2860 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2861 	if (rc < 0)
2862 		return rc;
2863 
2864 	tx_size = ISCSI_HDR_LEN;
2865 	iov = &cmd->iov_misc[0];
2866 	iov[niov].iov_base	= cmd->pdu;
2867 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2868 
2869 	if (conn->conn_ops->HeaderDigest) {
2870 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2871 
2872 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, &cmd->pdu[0],
2873 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2874 
2875 		iov[0].iov_len += ISCSI_CRC_LEN;
2876 		tx_size += ISCSI_CRC_LEN;
2877 		pr_debug("Attaching CRC32C HeaderDigest to"
2878 			" Logout Response 0x%08x\n", *header_digest);
2879 	}
2880 	cmd->iov_misc_count = niov;
2881 	cmd->tx_size = tx_size;
2882 
2883 	return 0;
2884 }
2885 
2886 void
2887 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2888 		       struct iscsi_nopin *hdr, bool nopout_response)
2889 {
2890 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2891 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2892         hton24(hdr->dlength, cmd->buf_ptr_size);
2893 	if (nopout_response)
2894 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2895 	hdr->itt		= cmd->init_task_tag;
2896 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2897 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2898 				  conn->stat_sn;
2899 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2900 
2901 	if (nopout_response)
2902 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2903 
2904 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2905 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
2906 
2907 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2908 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2909 		"Solicitied" : "Unsolicitied", cmd->init_task_tag,
2910 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2911 }
2912 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2913 
2914 /*
2915  *	Unsolicited NOPIN, either requesting a response or not.
2916  */
2917 static int iscsit_send_unsolicited_nopin(
2918 	struct iscsi_cmd *cmd,
2919 	struct iscsi_conn *conn,
2920 	int want_response)
2921 {
2922 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2923 	int tx_size = ISCSI_HDR_LEN, ret;
2924 
2925 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
2926 
2927 	if (conn->conn_ops->HeaderDigest) {
2928 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2929 
2930 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2931 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2932 
2933 		tx_size += ISCSI_CRC_LEN;
2934 		pr_debug("Attaching CRC32C HeaderDigest to"
2935 			" NopIN 0x%08x\n", *header_digest);
2936 	}
2937 
2938 	cmd->iov_misc[0].iov_base	= cmd->pdu;
2939 	cmd->iov_misc[0].iov_len	= tx_size;
2940 	cmd->iov_misc_count	= 1;
2941 	cmd->tx_size		= tx_size;
2942 
2943 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2944 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2945 
2946 	ret = iscsit_send_tx_data(cmd, conn, 1);
2947 	if (ret < 0) {
2948 		iscsit_tx_thread_wait_for_tcp(conn);
2949 		return ret;
2950 	}
2951 
2952 	spin_lock_bh(&cmd->istate_lock);
2953 	cmd->i_state = want_response ?
2954 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
2955 	spin_unlock_bh(&cmd->istate_lock);
2956 
2957 	return 0;
2958 }
2959 
2960 static int
2961 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2962 {
2963 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2964 	struct kvec *iov;
2965 	u32 padding = 0;
2966 	int niov = 0, tx_size;
2967 
2968 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
2969 
2970 	tx_size = ISCSI_HDR_LEN;
2971 	iov = &cmd->iov_misc[0];
2972 	iov[niov].iov_base	= cmd->pdu;
2973 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
2974 
2975 	if (conn->conn_ops->HeaderDigest) {
2976 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
2977 
2978 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
2979 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
2980 
2981 		iov[0].iov_len += ISCSI_CRC_LEN;
2982 		tx_size += ISCSI_CRC_LEN;
2983 		pr_debug("Attaching CRC32C HeaderDigest"
2984 			" to NopIn 0x%08x\n", *header_digest);
2985 	}
2986 
2987 	/*
2988 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
2989 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
2990 	 */
2991 	if (cmd->buf_ptr_size) {
2992 		iov[niov].iov_base	= cmd->buf_ptr;
2993 		iov[niov++].iov_len	= cmd->buf_ptr_size;
2994 		tx_size += cmd->buf_ptr_size;
2995 
2996 		pr_debug("Echoing back %u bytes of ping"
2997 			" data.\n", cmd->buf_ptr_size);
2998 
2999 		padding = ((-cmd->buf_ptr_size) & 3);
3000 		if (padding != 0) {
3001 			iov[niov].iov_base = &cmd->pad_bytes;
3002 			iov[niov++].iov_len = padding;
3003 			tx_size += padding;
3004 			pr_debug("Attaching %u additional"
3005 				" padding bytes.\n", padding);
3006 		}
3007 		if (conn->conn_ops->DataDigest) {
3008 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3009 				cmd->buf_ptr, cmd->buf_ptr_size,
3010 				padding, (u8 *)&cmd->pad_bytes,
3011 				(u8 *)&cmd->data_crc);
3012 
3013 			iov[niov].iov_base = &cmd->data_crc;
3014 			iov[niov++].iov_len = ISCSI_CRC_LEN;
3015 			tx_size += ISCSI_CRC_LEN;
3016 			pr_debug("Attached DataDigest for %u"
3017 				" bytes of ping data, CRC 0x%08x\n",
3018 				cmd->buf_ptr_size, cmd->data_crc);
3019 		}
3020 	}
3021 
3022 	cmd->iov_misc_count = niov;
3023 	cmd->tx_size = tx_size;
3024 
3025 	return 0;
3026 }
3027 
3028 static int iscsit_send_r2t(
3029 	struct iscsi_cmd *cmd,
3030 	struct iscsi_conn *conn)
3031 {
3032 	int tx_size = 0;
3033 	struct iscsi_r2t *r2t;
3034 	struct iscsi_r2t_rsp *hdr;
3035 	int ret;
3036 
3037 	r2t = iscsit_get_r2t_from_list(cmd);
3038 	if (!r2t)
3039 		return -1;
3040 
3041 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3042 	memset(hdr, 0, ISCSI_HDR_LEN);
3043 	hdr->opcode		= ISCSI_OP_R2T;
3044 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3045 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3046 			(struct scsi_lun *)&hdr->lun);
3047 	hdr->itt		= cmd->init_task_tag;
3048 	spin_lock_bh(&conn->sess->ttt_lock);
3049 	r2t->targ_xfer_tag	= conn->sess->targ_xfer_tag++;
3050 	if (r2t->targ_xfer_tag == 0xFFFFFFFF)
3051 		r2t->targ_xfer_tag = conn->sess->targ_xfer_tag++;
3052 	spin_unlock_bh(&conn->sess->ttt_lock);
3053 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3054 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3055 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3056 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3057 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3058 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3059 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3060 
3061 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3062 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3063 	tx_size += ISCSI_HDR_LEN;
3064 
3065 	if (conn->conn_ops->HeaderDigest) {
3066 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3067 
3068 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3069 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3070 
3071 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3072 		tx_size += ISCSI_CRC_LEN;
3073 		pr_debug("Attaching CRC32 HeaderDigest for R2T"
3074 			" PDU 0x%08x\n", *header_digest);
3075 	}
3076 
3077 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3078 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3079 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3080 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3081 			r2t->offset, r2t->xfer_len, conn->cid);
3082 
3083 	cmd->iov_misc_count = 1;
3084 	cmd->tx_size = tx_size;
3085 
3086 	spin_lock_bh(&cmd->r2t_lock);
3087 	r2t->sent_r2t = 1;
3088 	spin_unlock_bh(&cmd->r2t_lock);
3089 
3090 	ret = iscsit_send_tx_data(cmd, conn, 1);
3091 	if (ret < 0) {
3092 		iscsit_tx_thread_wait_for_tcp(conn);
3093 		return ret;
3094 	}
3095 
3096 	spin_lock_bh(&cmd->dataout_timeout_lock);
3097 	iscsit_start_dataout_timer(cmd, conn);
3098 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3099 
3100 	return 0;
3101 }
3102 
3103 /*
3104  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3105  *		connection recovery.
3106  */
3107 int iscsit_build_r2ts_for_cmd(
3108 	struct iscsi_conn *conn,
3109 	struct iscsi_cmd *cmd,
3110 	bool recovery)
3111 {
3112 	int first_r2t = 1;
3113 	u32 offset = 0, xfer_len = 0;
3114 
3115 	spin_lock_bh(&cmd->r2t_lock);
3116 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3117 		spin_unlock_bh(&cmd->r2t_lock);
3118 		return 0;
3119 	}
3120 
3121 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3122 	    !recovery)
3123 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3124 
3125 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3126 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3127 			offset = cmd->r2t_offset;
3128 
3129 			if (first_r2t && recovery) {
3130 				int new_data_end = offset +
3131 					conn->sess->sess_ops->MaxBurstLength -
3132 					cmd->next_burst_len;
3133 
3134 				if (new_data_end > cmd->se_cmd.data_length)
3135 					xfer_len = cmd->se_cmd.data_length - offset;
3136 				else
3137 					xfer_len =
3138 						conn->sess->sess_ops->MaxBurstLength -
3139 						cmd->next_burst_len;
3140 			} else {
3141 				int new_data_end = offset +
3142 					conn->sess->sess_ops->MaxBurstLength;
3143 
3144 				if (new_data_end > cmd->se_cmd.data_length)
3145 					xfer_len = cmd->se_cmd.data_length - offset;
3146 				else
3147 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3148 			}
3149 			cmd->r2t_offset += xfer_len;
3150 
3151 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3152 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3153 		} else {
3154 			struct iscsi_seq *seq;
3155 
3156 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3157 			if (!seq) {
3158 				spin_unlock_bh(&cmd->r2t_lock);
3159 				return -1;
3160 			}
3161 
3162 			offset = seq->offset;
3163 			xfer_len = seq->xfer_len;
3164 
3165 			if (cmd->seq_send_order == cmd->seq_count)
3166 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3167 		}
3168 		cmd->outstanding_r2ts++;
3169 		first_r2t = 0;
3170 
3171 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3172 			spin_unlock_bh(&cmd->r2t_lock);
3173 			return -1;
3174 		}
3175 
3176 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3177 			break;
3178 	}
3179 	spin_unlock_bh(&cmd->r2t_lock);
3180 
3181 	return 0;
3182 }
3183 
3184 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3185 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3186 {
3187 	if (inc_stat_sn)
3188 		cmd->stat_sn = conn->stat_sn++;
3189 
3190 	atomic_long_inc(&conn->sess->rsp_pdus);
3191 
3192 	memset(hdr, 0, ISCSI_HDR_LEN);
3193 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3194 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3195 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3196 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3197 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3198 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3199 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3200 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3201 	}
3202 	hdr->response		= cmd->iscsi_response;
3203 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3204 	hdr->itt		= cmd->init_task_tag;
3205 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3206 
3207 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3208 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3209 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3210 
3211 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3212 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3213 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3214 		cmd->se_cmd.scsi_status, conn->cid);
3215 }
3216 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3217 
3218 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3219 {
3220 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3221 	struct kvec *iov;
3222 	u32 padding = 0, tx_size = 0;
3223 	int iov_count = 0;
3224 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3225 
3226 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3227 
3228 	iov = &cmd->iov_misc[0];
3229 	iov[iov_count].iov_base	= cmd->pdu;
3230 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3231 	tx_size += ISCSI_HDR_LEN;
3232 
3233 	/*
3234 	 * Attach SENSE DATA payload to iSCSI Response PDU
3235 	 */
3236 	if (cmd->se_cmd.sense_buffer &&
3237 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3238 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3239 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3240 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3241 
3242 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3243 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3244 		iov[iov_count].iov_base	= cmd->sense_buffer;
3245 		iov[iov_count++].iov_len =
3246 				(cmd->se_cmd.scsi_sense_length + padding);
3247 		tx_size += cmd->se_cmd.scsi_sense_length;
3248 
3249 		if (padding) {
3250 			memset(cmd->sense_buffer +
3251 				cmd->se_cmd.scsi_sense_length, 0, padding);
3252 			tx_size += padding;
3253 			pr_debug("Adding %u bytes of padding to"
3254 				" SENSE.\n", padding);
3255 		}
3256 
3257 		if (conn->conn_ops->DataDigest) {
3258 			iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3259 				cmd->sense_buffer,
3260 				(cmd->se_cmd.scsi_sense_length + padding),
3261 				0, NULL, (u8 *)&cmd->data_crc);
3262 
3263 			iov[iov_count].iov_base    = &cmd->data_crc;
3264 			iov[iov_count++].iov_len     = ISCSI_CRC_LEN;
3265 			tx_size += ISCSI_CRC_LEN;
3266 
3267 			pr_debug("Attaching CRC32 DataDigest for"
3268 				" SENSE, %u bytes CRC 0x%08x\n",
3269 				(cmd->se_cmd.scsi_sense_length + padding),
3270 				cmd->data_crc);
3271 		}
3272 
3273 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3274 				" Response PDU\n",
3275 				cmd->se_cmd.scsi_sense_length);
3276 	}
3277 
3278 	if (conn->conn_ops->HeaderDigest) {
3279 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3280 
3281 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->pdu,
3282 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3283 
3284 		iov[0].iov_len += ISCSI_CRC_LEN;
3285 		tx_size += ISCSI_CRC_LEN;
3286 		pr_debug("Attaching CRC32 HeaderDigest for Response"
3287 				" PDU 0x%08x\n", *header_digest);
3288 	}
3289 
3290 	cmd->iov_misc_count = iov_count;
3291 	cmd->tx_size = tx_size;
3292 
3293 	return 0;
3294 }
3295 
3296 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3297 {
3298 	switch (se_tmr->response) {
3299 	case TMR_FUNCTION_COMPLETE:
3300 		return ISCSI_TMF_RSP_COMPLETE;
3301 	case TMR_TASK_DOES_NOT_EXIST:
3302 		return ISCSI_TMF_RSP_NO_TASK;
3303 	case TMR_LUN_DOES_NOT_EXIST:
3304 		return ISCSI_TMF_RSP_NO_LUN;
3305 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3306 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3307 	case TMR_FUNCTION_REJECTED:
3308 	default:
3309 		return ISCSI_TMF_RSP_REJECTED;
3310 	}
3311 }
3312 
3313 void
3314 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3315 			  struct iscsi_tm_rsp *hdr)
3316 {
3317 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3318 
3319 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3320 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3321 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3322 	hdr->itt		= cmd->init_task_tag;
3323 	cmd->stat_sn		= conn->stat_sn++;
3324 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3325 
3326 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3327 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3328 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3329 
3330 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3331 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3332 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3333 }
3334 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3335 
3336 static int
3337 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3338 {
3339 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3340 	u32 tx_size = 0;
3341 
3342 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3343 
3344 	cmd->iov_misc[0].iov_base	= cmd->pdu;
3345 	cmd->iov_misc[0].iov_len	= ISCSI_HDR_LEN;
3346 	tx_size += ISCSI_HDR_LEN;
3347 
3348 	if (conn->conn_ops->HeaderDigest) {
3349 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3350 
3351 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3352 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3353 
3354 		cmd->iov_misc[0].iov_len += ISCSI_CRC_LEN;
3355 		tx_size += ISCSI_CRC_LEN;
3356 		pr_debug("Attaching CRC32 HeaderDigest for Task"
3357 			" Mgmt Response PDU 0x%08x\n", *header_digest);
3358 	}
3359 
3360 	cmd->iov_misc_count = 1;
3361 	cmd->tx_size = tx_size;
3362 
3363 	return 0;
3364 }
3365 
3366 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3367 {
3368 	bool ret = false;
3369 
3370 	if (np->np_sockaddr.ss_family == AF_INET6) {
3371 		const struct sockaddr_in6 sin6 = {
3372 			.sin6_addr = IN6ADDR_ANY_INIT };
3373 		struct sockaddr_in6 *sock_in6 =
3374 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3375 
3376 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3377 				sin6.sin6_addr.s6_addr, 16))
3378 			ret = true;
3379 	} else {
3380 		struct sockaddr_in * sock_in =
3381 			(struct sockaddr_in *)&np->np_sockaddr;
3382 
3383 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3384 			ret = true;
3385 	}
3386 
3387 	return ret;
3388 }
3389 
3390 #define SENDTARGETS_BUF_LIMIT 32768U
3391 
3392 static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
3393 {
3394 	char *payload = NULL;
3395 	struct iscsi_conn *conn = cmd->conn;
3396 	struct iscsi_portal_group *tpg;
3397 	struct iscsi_tiqn *tiqn;
3398 	struct iscsi_tpg_np *tpg_np;
3399 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3400 	int target_name_printed;
3401 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3402 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3403 
3404 	buffer_len = max(conn->conn_ops->MaxRecvDataSegmentLength,
3405 			 SENDTARGETS_BUF_LIMIT);
3406 
3407 	payload = kzalloc(buffer_len, GFP_KERNEL);
3408 	if (!payload) {
3409 		pr_err("Unable to allocate memory for sendtargets"
3410 				" response.\n");
3411 		return -ENOMEM;
3412 	}
3413 	/*
3414 	 * Locate pointer to iqn./eui. string for IFC_SENDTARGETS_SINGLE
3415 	 * explicit case..
3416 	 */
3417 	if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) {
3418 		text_ptr = strchr(text_in, '=');
3419 		if (!text_ptr) {
3420 			pr_err("Unable to locate '=' string in text_in:"
3421 			       " %s\n", text_in);
3422 			kfree(payload);
3423 			return -EINVAL;
3424 		}
3425 		/*
3426 		 * Skip over '=' character..
3427 		 */
3428 		text_ptr += 1;
3429 	}
3430 
3431 	spin_lock(&tiqn_lock);
3432 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3433 		if ((cmd->cmd_flags & IFC_SENDTARGETS_SINGLE) &&
3434 		     strcmp(tiqn->tiqn, text_ptr)) {
3435 			continue;
3436 		}
3437 
3438 		target_name_printed = 0;
3439 
3440 		spin_lock(&tiqn->tiqn_tpg_lock);
3441 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3442 
3443 			/* If demo_mode_discovery=0 and generate_node_acls=0
3444 			 * (demo mode dislabed) do not return
3445 			 * TargetName+TargetAddress unless a NodeACL exists.
3446 			 */
3447 
3448 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3449 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3450 			    (!core_tpg_get_initiator_node_acl(&tpg->tpg_se_tpg,
3451 				cmd->conn->sess->sess_ops->InitiatorName))) {
3452 				continue;
3453 			}
3454 
3455 			spin_lock(&tpg->tpg_state_lock);
3456 			if ((tpg->tpg_state == TPG_STATE_FREE) ||
3457 			    (tpg->tpg_state == TPG_STATE_INACTIVE)) {
3458 				spin_unlock(&tpg->tpg_state_lock);
3459 				continue;
3460 			}
3461 			spin_unlock(&tpg->tpg_state_lock);
3462 
3463 			spin_lock(&tpg->tpg_np_lock);
3464 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3465 						tpg_np_list) {
3466 				struct iscsi_np *np = tpg_np->tpg_np;
3467 				bool inaddr_any = iscsit_check_inaddr_any(np);
3468 
3469 				if (!target_name_printed) {
3470 					len = sprintf(buf, "TargetName=%s",
3471 						      tiqn->tiqn);
3472 					len += 1;
3473 
3474 					if ((len + payload_len) > buffer_len) {
3475 						spin_unlock(&tpg->tpg_np_lock);
3476 						spin_unlock(&tiqn->tiqn_tpg_lock);
3477 						end_of_buf = 1;
3478 						goto eob;
3479 					}
3480 					memcpy(payload + payload_len, buf, len);
3481 					payload_len += len;
3482 					target_name_printed = 1;
3483 				}
3484 
3485 				len = sprintf(buf, "TargetAddress="
3486 					"%s:%hu,%hu",
3487 					(inaddr_any == false) ?
3488 						np->np_ip : conn->local_ip,
3489 					(inaddr_any == false) ?
3490 						np->np_port : conn->local_port,
3491 					tpg->tpgt);
3492 				len += 1;
3493 
3494 				if ((len + payload_len) > buffer_len) {
3495 					spin_unlock(&tpg->tpg_np_lock);
3496 					spin_unlock(&tiqn->tiqn_tpg_lock);
3497 					end_of_buf = 1;
3498 					goto eob;
3499 				}
3500 				memcpy(payload + payload_len, buf, len);
3501 				payload_len += len;
3502 			}
3503 			spin_unlock(&tpg->tpg_np_lock);
3504 		}
3505 		spin_unlock(&tiqn->tiqn_tpg_lock);
3506 eob:
3507 		if (end_of_buf)
3508 			break;
3509 
3510 		if (cmd->cmd_flags & IFC_SENDTARGETS_SINGLE)
3511 			break;
3512 	}
3513 	spin_unlock(&tiqn_lock);
3514 
3515 	cmd->buf_ptr = payload;
3516 
3517 	return payload_len;
3518 }
3519 
3520 int
3521 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3522 		      struct iscsi_text_rsp *hdr)
3523 {
3524 	int text_length, padding;
3525 
3526 	text_length = iscsit_build_sendtargets_response(cmd);
3527 	if (text_length < 0)
3528 		return text_length;
3529 
3530 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3531 	hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3532 	padding = ((-text_length) & 3);
3533 	hton24(hdr->dlength, text_length);
3534 	hdr->itt = cmd->init_task_tag;
3535 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3536 	cmd->stat_sn = conn->stat_sn++;
3537 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3538 
3539 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3540 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3541 	hdr->max_cmdsn = cpu_to_be32(conn->sess->max_cmd_sn);
3542 
3543 	pr_debug("Built Text Response: ITT: 0x%08x, StatSN: 0x%08x,"
3544 		" Length: %u, CID: %hu\n", cmd->init_task_tag, cmd->stat_sn,
3545 		text_length, conn->cid);
3546 
3547 	return text_length + padding;
3548 }
3549 EXPORT_SYMBOL(iscsit_build_text_rsp);
3550 
3551 /*
3552  *	FIXME: Add support for F_BIT and C_BIT when the length is longer than
3553  *	MaxRecvDataSegmentLength.
3554  */
3555 static int iscsit_send_text_rsp(
3556 	struct iscsi_cmd *cmd,
3557 	struct iscsi_conn *conn)
3558 {
3559 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3560 	struct kvec *iov;
3561 	u32 tx_size = 0;
3562 	int text_length, iov_count = 0, rc;
3563 
3564 	rc = iscsit_build_text_rsp(cmd, conn, hdr);
3565 	if (rc < 0)
3566 		return rc;
3567 
3568 	text_length = rc;
3569 	iov = &cmd->iov_misc[0];
3570 	iov[iov_count].iov_base = cmd->pdu;
3571 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3572 	iov[iov_count].iov_base	= cmd->buf_ptr;
3573 	iov[iov_count++].iov_len = text_length;
3574 
3575 	tx_size += (ISCSI_HDR_LEN + text_length);
3576 
3577 	if (conn->conn_ops->HeaderDigest) {
3578 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3579 
3580 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3581 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3582 
3583 		iov[0].iov_len += ISCSI_CRC_LEN;
3584 		tx_size += ISCSI_CRC_LEN;
3585 		pr_debug("Attaching CRC32 HeaderDigest for"
3586 			" Text Response PDU 0x%08x\n", *header_digest);
3587 	}
3588 
3589 	if (conn->conn_ops->DataDigest) {
3590 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash,
3591 				cmd->buf_ptr, text_length,
3592 				0, NULL, (u8 *)&cmd->data_crc);
3593 
3594 		iov[iov_count].iov_base	= &cmd->data_crc;
3595 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
3596 		tx_size	+= ISCSI_CRC_LEN;
3597 
3598 		pr_debug("Attaching DataDigest for %u bytes of text"
3599 			" data, CRC 0x%08x\n", text_length,
3600 			cmd->data_crc);
3601 	}
3602 
3603 	cmd->iov_misc_count = iov_count;
3604 	cmd->tx_size = tx_size;
3605 
3606 	return 0;
3607 }
3608 
3609 void
3610 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3611 		    struct iscsi_reject *hdr)
3612 {
3613 	hdr->opcode		= ISCSI_OP_REJECT;
3614 	hdr->reason		= cmd->reject_reason;
3615 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3616 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3617 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3618 	cmd->stat_sn		= conn->stat_sn++;
3619 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3620 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3621 	hdr->max_cmdsn		= cpu_to_be32(conn->sess->max_cmd_sn);
3622 
3623 }
3624 EXPORT_SYMBOL(iscsit_build_reject);
3625 
3626 static int iscsit_send_reject(
3627 	struct iscsi_cmd *cmd,
3628 	struct iscsi_conn *conn)
3629 {
3630 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3631 	struct kvec *iov;
3632 	u32 iov_count = 0, tx_size;
3633 
3634 	iscsit_build_reject(cmd, conn, hdr);
3635 
3636 	iov = &cmd->iov_misc[0];
3637 	iov[iov_count].iov_base = cmd->pdu;
3638 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3639 	iov[iov_count].iov_base = cmd->buf_ptr;
3640 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
3641 
3642 	tx_size = (ISCSI_HDR_LEN + ISCSI_HDR_LEN);
3643 
3644 	if (conn->conn_ops->HeaderDigest) {
3645 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
3646 
3647 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, hdr,
3648 				ISCSI_HDR_LEN, 0, NULL, (u8 *)header_digest);
3649 
3650 		iov[0].iov_len += ISCSI_CRC_LEN;
3651 		tx_size += ISCSI_CRC_LEN;
3652 		pr_debug("Attaching CRC32 HeaderDigest for"
3653 			" REJECT PDU 0x%08x\n", *header_digest);
3654 	}
3655 
3656 	if (conn->conn_ops->DataDigest) {
3657 		iscsit_do_crypto_hash_buf(&conn->conn_tx_hash, cmd->buf_ptr,
3658 				ISCSI_HDR_LEN, 0, NULL, (u8 *)&cmd->data_crc);
3659 
3660 		iov[iov_count].iov_base = &cmd->data_crc;
3661 		iov[iov_count++].iov_len  = ISCSI_CRC_LEN;
3662 		tx_size += ISCSI_CRC_LEN;
3663 		pr_debug("Attaching CRC32 DataDigest for REJECT"
3664 				" PDU 0x%08x\n", cmd->data_crc);
3665 	}
3666 
3667 	cmd->iov_misc_count = iov_count;
3668 	cmd->tx_size = tx_size;
3669 
3670 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3671 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3672 
3673 	return 0;
3674 }
3675 
3676 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3677 {
3678 	struct iscsi_thread_set *ts = conn->thread_set;
3679 	int ord, cpu;
3680 	/*
3681 	 * thread_id is assigned from iscsit_global->ts_bitmap from
3682 	 * within iscsi_thread_set.c:iscsi_allocate_thread_sets()
3683 	 *
3684 	 * Here we use thread_id to determine which CPU that this
3685 	 * iSCSI connection's iscsi_thread_set will be scheduled to
3686 	 * execute upon.
3687 	 */
3688 	ord = ts->thread_id % cpumask_weight(cpu_online_mask);
3689 	for_each_online_cpu(cpu) {
3690 		if (ord-- == 0) {
3691 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3692 			return;
3693 		}
3694 	}
3695 	/*
3696 	 * This should never be reached..
3697 	 */
3698 	dump_stack();
3699 	cpumask_setall(conn->conn_cpumask);
3700 }
3701 
3702 static inline void iscsit_thread_check_cpumask(
3703 	struct iscsi_conn *conn,
3704 	struct task_struct *p,
3705 	int mode)
3706 {
3707 	char buf[128];
3708 	/*
3709 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3710 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3711 	 */
3712 	if (mode == 1) {
3713 		if (!conn->conn_tx_reset_cpumask)
3714 			return;
3715 		conn->conn_tx_reset_cpumask = 0;
3716 	} else {
3717 		if (!conn->conn_rx_reset_cpumask)
3718 			return;
3719 		conn->conn_rx_reset_cpumask = 0;
3720 	}
3721 	/*
3722 	 * Update the CPU mask for this single kthread so that
3723 	 * both TX and RX kthreads are scheduled to run on the
3724 	 * same CPU.
3725 	 */
3726 	memset(buf, 0, 128);
3727 	cpumask_scnprintf(buf, 128, conn->conn_cpumask);
3728 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3729 }
3730 
3731 static int
3732 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3733 {
3734 	int ret;
3735 
3736 	switch (state) {
3737 	case ISTATE_SEND_R2T:
3738 		ret = iscsit_send_r2t(cmd, conn);
3739 		if (ret < 0)
3740 			goto err;
3741 		break;
3742 	case ISTATE_REMOVE:
3743 		spin_lock_bh(&conn->cmd_lock);
3744 		list_del_init(&cmd->i_conn_node);
3745 		spin_unlock_bh(&conn->cmd_lock);
3746 
3747 		iscsit_free_cmd(cmd, false);
3748 		break;
3749 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3750 		iscsit_mod_nopin_response_timer(conn);
3751 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3752 		if (ret < 0)
3753 			goto err;
3754 		break;
3755 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3756 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3757 		if (ret < 0)
3758 			goto err;
3759 		break;
3760 	default:
3761 		pr_err("Unknown Opcode: 0x%02x ITT:"
3762 		       " 0x%08x, i_state: %d on CID: %hu\n",
3763 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3764 		       conn->cid);
3765 		goto err;
3766 	}
3767 
3768 	return 0;
3769 
3770 err:
3771 	return -1;
3772 }
3773 
3774 static int
3775 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3776 {
3777 	struct iscsit_transport *t = conn->conn_transport;
3778 	struct iscsi_queue_req *qr;
3779 	struct iscsi_cmd *cmd;
3780 	u8 state;
3781 	int ret;
3782 
3783 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3784 		atomic_set(&conn->check_immediate_queue, 0);
3785 		cmd = qr->cmd;
3786 		state = qr->state;
3787 		kmem_cache_free(lio_qr_cache, qr);
3788 
3789 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3790 		if (ret < 0)
3791 			return ret;
3792 	}
3793 
3794 	return 0;
3795 }
3796 
3797 static int
3798 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3799 {
3800 	int ret;
3801 
3802 check_rsp_state:
3803 	switch (state) {
3804 	case ISTATE_SEND_DATAIN:
3805 		ret = iscsit_send_datain(cmd, conn);
3806 		if (ret < 0)
3807 			goto err;
3808 		else if (!ret)
3809 			/* more drs */
3810 			goto check_rsp_state;
3811 		else if (ret == 1) {
3812 			/* all done */
3813 			spin_lock_bh(&cmd->istate_lock);
3814 			cmd->i_state = ISTATE_SENT_STATUS;
3815 			spin_unlock_bh(&cmd->istate_lock);
3816 
3817 			if (atomic_read(&conn->check_immediate_queue))
3818 				return 1;
3819 
3820 			return 0;
3821 		} else if (ret == 2) {
3822 			/* Still must send status,
3823 			   SCF_TRANSPORT_TASK_SENSE was set */
3824 			spin_lock_bh(&cmd->istate_lock);
3825 			cmd->i_state = ISTATE_SEND_STATUS;
3826 			spin_unlock_bh(&cmd->istate_lock);
3827 			state = ISTATE_SEND_STATUS;
3828 			goto check_rsp_state;
3829 		}
3830 
3831 		break;
3832 	case ISTATE_SEND_STATUS:
3833 	case ISTATE_SEND_STATUS_RECOVERY:
3834 		ret = iscsit_send_response(cmd, conn);
3835 		break;
3836 	case ISTATE_SEND_LOGOUTRSP:
3837 		ret = iscsit_send_logout(cmd, conn);
3838 		break;
3839 	case ISTATE_SEND_ASYNCMSG:
3840 		ret = iscsit_send_conn_drop_async_message(
3841 			cmd, conn);
3842 		break;
3843 	case ISTATE_SEND_NOPIN:
3844 		ret = iscsit_send_nopin(cmd, conn);
3845 		break;
3846 	case ISTATE_SEND_REJECT:
3847 		ret = iscsit_send_reject(cmd, conn);
3848 		break;
3849 	case ISTATE_SEND_TASKMGTRSP:
3850 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3851 		if (ret != 0)
3852 			break;
3853 		ret = iscsit_tmr_post_handler(cmd, conn);
3854 		if (ret != 0)
3855 			iscsit_fall_back_to_erl0(conn->sess);
3856 		break;
3857 	case ISTATE_SEND_TEXTRSP:
3858 		ret = iscsit_send_text_rsp(cmd, conn);
3859 		break;
3860 	default:
3861 		pr_err("Unknown Opcode: 0x%02x ITT:"
3862 		       " 0x%08x, i_state: %d on CID: %hu\n",
3863 		       cmd->iscsi_opcode, cmd->init_task_tag,
3864 		       state, conn->cid);
3865 		goto err;
3866 	}
3867 	if (ret < 0)
3868 		goto err;
3869 
3870 	if (iscsit_send_tx_data(cmd, conn, 1) < 0) {
3871 		iscsit_tx_thread_wait_for_tcp(conn);
3872 		iscsit_unmap_iovec(cmd);
3873 		goto err;
3874 	}
3875 	iscsit_unmap_iovec(cmd);
3876 
3877 	switch (state) {
3878 	case ISTATE_SEND_LOGOUTRSP:
3879 		if (!iscsit_logout_post_handler(cmd, conn))
3880 			goto restart;
3881 		/* fall through */
3882 	case ISTATE_SEND_STATUS:
3883 	case ISTATE_SEND_ASYNCMSG:
3884 	case ISTATE_SEND_NOPIN:
3885 	case ISTATE_SEND_STATUS_RECOVERY:
3886 	case ISTATE_SEND_TEXTRSP:
3887 	case ISTATE_SEND_TASKMGTRSP:
3888 	case ISTATE_SEND_REJECT:
3889 		spin_lock_bh(&cmd->istate_lock);
3890 		cmd->i_state = ISTATE_SENT_STATUS;
3891 		spin_unlock_bh(&cmd->istate_lock);
3892 		break;
3893 	default:
3894 		pr_err("Unknown Opcode: 0x%02x ITT:"
3895 		       " 0x%08x, i_state: %d on CID: %hu\n",
3896 		       cmd->iscsi_opcode, cmd->init_task_tag,
3897 		       cmd->i_state, conn->cid);
3898 		goto err;
3899 	}
3900 
3901 	if (atomic_read(&conn->check_immediate_queue))
3902 		return 1;
3903 
3904 	return 0;
3905 
3906 err:
3907 	return -1;
3908 restart:
3909 	return -EAGAIN;
3910 }
3911 
3912 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3913 {
3914 	struct iscsit_transport *t = conn->conn_transport;
3915 	struct iscsi_queue_req *qr;
3916 	struct iscsi_cmd *cmd;
3917 	u8 state;
3918 	int ret;
3919 
3920 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3921 		cmd = qr->cmd;
3922 		state = qr->state;
3923 		kmem_cache_free(lio_qr_cache, qr);
3924 
3925 		ret = t->iscsit_response_queue(conn, cmd, state);
3926 		if (ret == 1 || ret < 0)
3927 			return ret;
3928 	}
3929 
3930 	return 0;
3931 }
3932 
3933 int iscsi_target_tx_thread(void *arg)
3934 {
3935 	int ret = 0;
3936 	struct iscsi_conn *conn;
3937 	struct iscsi_thread_set *ts = arg;
3938 	/*
3939 	 * Allow ourselves to be interrupted by SIGINT so that a
3940 	 * connection recovery / failure event can be triggered externally.
3941 	 */
3942 	allow_signal(SIGINT);
3943 
3944 restart:
3945 	conn = iscsi_tx_thread_pre_handler(ts);
3946 	if (!conn)
3947 		goto out;
3948 
3949 	ret = 0;
3950 
3951 	while (!kthread_should_stop()) {
3952 		/*
3953 		 * Ensure that both TX and RX per connection kthreads
3954 		 * are scheduled to run on the same CPU.
3955 		 */
3956 		iscsit_thread_check_cpumask(conn, current, 1);
3957 
3958 		wait_event_interruptible(conn->queues_wq,
3959 					 !iscsit_conn_all_queues_empty(conn) ||
3960 					 ts->status == ISCSI_THREAD_SET_RESET);
3961 
3962 		if ((ts->status == ISCSI_THREAD_SET_RESET) ||
3963 		     signal_pending(current))
3964 			goto transport_err;
3965 
3966 get_immediate:
3967 		ret = iscsit_handle_immediate_queue(conn);
3968 		if (ret < 0)
3969 			goto transport_err;
3970 
3971 		ret = iscsit_handle_response_queue(conn);
3972 		if (ret == 1)
3973 			goto get_immediate;
3974 		else if (ret == -EAGAIN)
3975 			goto restart;
3976 		else if (ret < 0)
3977 			goto transport_err;
3978 	}
3979 
3980 transport_err:
3981 	iscsit_take_action_for_connection_exit(conn);
3982 	goto restart;
3983 out:
3984 	return 0;
3985 }
3986 
3987 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3988 {
3989 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3990 	struct iscsi_cmd *cmd;
3991 	int ret = 0;
3992 
3993 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3994 	case ISCSI_OP_SCSI_CMD:
3995 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3996 		if (!cmd)
3997 			goto reject;
3998 
3999 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
4000 		break;
4001 	case ISCSI_OP_SCSI_DATA_OUT:
4002 		ret = iscsit_handle_data_out(conn, buf);
4003 		break;
4004 	case ISCSI_OP_NOOP_OUT:
4005 		cmd = NULL;
4006 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
4007 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4008 			if (!cmd)
4009 				goto reject;
4010 		}
4011 		ret = iscsit_handle_nop_out(conn, cmd, buf);
4012 		break;
4013 	case ISCSI_OP_SCSI_TMFUNC:
4014 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4015 		if (!cmd)
4016 			goto reject;
4017 
4018 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
4019 		break;
4020 	case ISCSI_OP_TEXT:
4021 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4022 		if (!cmd)
4023 			goto reject;
4024 
4025 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
4026 		break;
4027 	case ISCSI_OP_LOGOUT:
4028 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4029 		if (!cmd)
4030 			goto reject;
4031 
4032 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
4033 		if (ret > 0)
4034 			wait_for_completion_timeout(&conn->conn_logout_comp,
4035 					SECONDS_FOR_LOGOUT_COMP * HZ);
4036 		break;
4037 	case ISCSI_OP_SNACK:
4038 		ret = iscsit_handle_snack(conn, buf);
4039 		break;
4040 	default:
4041 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
4042 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
4043 			pr_err("Cannot recover from unknown"
4044 			" opcode while ERL=0, closing iSCSI connection.\n");
4045 			return -1;
4046 		}
4047 		if (!conn->conn_ops->OFMarker) {
4048 			pr_err("Unable to recover from unknown"
4049 			" opcode while OFMarker=No, closing iSCSI"
4050 				" connection.\n");
4051 			return -1;
4052 		}
4053 		if (iscsit_recover_from_unknown_opcode(conn) < 0) {
4054 			pr_err("Unable to recover from unknown"
4055 				" opcode, closing iSCSI connection.\n");
4056 			return -1;
4057 		}
4058 		break;
4059 	}
4060 
4061 	return ret;
4062 reject:
4063 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4064 }
4065 
4066 int iscsi_target_rx_thread(void *arg)
4067 {
4068 	int ret;
4069 	u8 buffer[ISCSI_HDR_LEN], opcode;
4070 	u32 checksum = 0, digest = 0;
4071 	struct iscsi_conn *conn = NULL;
4072 	struct iscsi_thread_set *ts = arg;
4073 	struct kvec iov;
4074 	/*
4075 	 * Allow ourselves to be interrupted by SIGINT so that a
4076 	 * connection recovery / failure event can be triggered externally.
4077 	 */
4078 	allow_signal(SIGINT);
4079 
4080 restart:
4081 	conn = iscsi_rx_thread_pre_handler(ts);
4082 	if (!conn)
4083 		goto out;
4084 
4085 	if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) {
4086 		struct completion comp;
4087 		int rc;
4088 
4089 		init_completion(&comp);
4090 		rc = wait_for_completion_interruptible(&comp);
4091 		if (rc < 0)
4092 			goto transport_err;
4093 
4094 		goto out;
4095 	}
4096 
4097 	while (!kthread_should_stop()) {
4098 		/*
4099 		 * Ensure that both TX and RX per connection kthreads
4100 		 * are scheduled to run on the same CPU.
4101 		 */
4102 		iscsit_thread_check_cpumask(conn, current, 0);
4103 
4104 		memset(buffer, 0, ISCSI_HDR_LEN);
4105 		memset(&iov, 0, sizeof(struct kvec));
4106 
4107 		iov.iov_base	= buffer;
4108 		iov.iov_len	= ISCSI_HDR_LEN;
4109 
4110 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4111 		if (ret != ISCSI_HDR_LEN) {
4112 			iscsit_rx_thread_wait_for_tcp(conn);
4113 			goto transport_err;
4114 		}
4115 
4116 		if (conn->conn_ops->HeaderDigest) {
4117 			iov.iov_base	= &digest;
4118 			iov.iov_len	= ISCSI_CRC_LEN;
4119 
4120 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4121 			if (ret != ISCSI_CRC_LEN) {
4122 				iscsit_rx_thread_wait_for_tcp(conn);
4123 				goto transport_err;
4124 			}
4125 
4126 			iscsit_do_crypto_hash_buf(&conn->conn_rx_hash,
4127 					buffer, ISCSI_HDR_LEN,
4128 					0, NULL, (u8 *)&checksum);
4129 
4130 			if (digest != checksum) {
4131 				pr_err("HeaderDigest CRC32C failed,"
4132 					" received 0x%08x, computed 0x%08x\n",
4133 					digest, checksum);
4134 				/*
4135 				 * Set the PDU to 0xff so it will intentionally
4136 				 * hit default in the switch below.
4137 				 */
4138 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4139 				atomic_long_inc(&conn->sess->conn_digest_errors);
4140 			} else {
4141 				pr_debug("Got HeaderDigest CRC32C"
4142 						" 0x%08x\n", checksum);
4143 			}
4144 		}
4145 
4146 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4147 			goto transport_err;
4148 
4149 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4150 
4151 		if (conn->sess->sess_ops->SessionType &&
4152 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4153 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4154 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4155 			" while in Discovery Session, rejecting.\n", opcode);
4156 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4157 					  buffer);
4158 			goto transport_err;
4159 		}
4160 
4161 		ret = iscsi_target_rx_opcode(conn, buffer);
4162 		if (ret < 0)
4163 			goto transport_err;
4164 	}
4165 
4166 transport_err:
4167 	if (!signal_pending(current))
4168 		atomic_set(&conn->transport_failed, 1);
4169 	iscsit_take_action_for_connection_exit(conn);
4170 	goto restart;
4171 out:
4172 	return 0;
4173 }
4174 
4175 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4176 {
4177 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4178 	struct iscsi_session *sess = conn->sess;
4179 	/*
4180 	 * We expect this function to only ever be called from either RX or TX
4181 	 * thread context via iscsit_close_connection() once the other context
4182 	 * has been reset -> returned sleeping pre-handler state.
4183 	 */
4184 	spin_lock_bh(&conn->cmd_lock);
4185 	list_for_each_entry_safe(cmd, cmd_tmp, &conn->conn_cmd_list, i_conn_node) {
4186 
4187 		list_del_init(&cmd->i_conn_node);
4188 		spin_unlock_bh(&conn->cmd_lock);
4189 
4190 		iscsit_increment_maxcmdsn(cmd, sess);
4191 
4192 		iscsit_free_cmd(cmd, true);
4193 
4194 		spin_lock_bh(&conn->cmd_lock);
4195 	}
4196 	spin_unlock_bh(&conn->cmd_lock);
4197 }
4198 
4199 static void iscsit_stop_timers_for_cmds(
4200 	struct iscsi_conn *conn)
4201 {
4202 	struct iscsi_cmd *cmd;
4203 
4204 	spin_lock_bh(&conn->cmd_lock);
4205 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4206 		if (cmd->data_direction == DMA_TO_DEVICE)
4207 			iscsit_stop_dataout_timer(cmd);
4208 	}
4209 	spin_unlock_bh(&conn->cmd_lock);
4210 }
4211 
4212 int iscsit_close_connection(
4213 	struct iscsi_conn *conn)
4214 {
4215 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4216 	struct iscsi_session	*sess = conn->sess;
4217 
4218 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4219 		" %u\n", conn->cid, sess->sid);
4220 	/*
4221 	 * Always up conn_logout_comp just in case the RX Thread is sleeping
4222 	 * and the logout response never got sent because the connection
4223 	 * failed.
4224 	 */
4225 	complete(&conn->conn_logout_comp);
4226 
4227 	iscsi_release_thread_set(conn);
4228 
4229 	iscsit_stop_timers_for_cmds(conn);
4230 	iscsit_stop_nopin_response_timer(conn);
4231 	iscsit_stop_nopin_timer(conn);
4232 
4233 	if (conn->conn_transport->iscsit_wait_conn)
4234 		conn->conn_transport->iscsit_wait_conn(conn);
4235 
4236 	iscsit_free_queue_reqs_for_conn(conn);
4237 
4238 	/*
4239 	 * During Connection recovery drop unacknowledged out of order
4240 	 * commands for this connection, and prepare the other commands
4241 	 * for realligence.
4242 	 *
4243 	 * During normal operation clear the out of order commands (but
4244 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4245 	 * struct iscsi_cmds.
4246 	 */
4247 	if (atomic_read(&conn->connection_recovery)) {
4248 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4249 		iscsit_prepare_cmds_for_realligance(conn);
4250 	} else {
4251 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4252 		iscsit_release_commands_from_conn(conn);
4253 	}
4254 
4255 	/*
4256 	 * Handle decrementing session or connection usage count if
4257 	 * a logout response was not able to be sent because the
4258 	 * connection failed.  Fall back to Session Recovery here.
4259 	 */
4260 	if (atomic_read(&conn->conn_logout_remove)) {
4261 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4262 			iscsit_dec_conn_usage_count(conn);
4263 			iscsit_dec_session_usage_count(sess);
4264 		}
4265 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4266 			iscsit_dec_conn_usage_count(conn);
4267 
4268 		atomic_set(&conn->conn_logout_remove, 0);
4269 		atomic_set(&sess->session_reinstatement, 0);
4270 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4271 	}
4272 
4273 	spin_lock_bh(&sess->conn_lock);
4274 	list_del(&conn->conn_list);
4275 
4276 	/*
4277 	 * Attempt to let the Initiator know this connection failed by
4278 	 * sending an Connection Dropped Async Message on another
4279 	 * active connection.
4280 	 */
4281 	if (atomic_read(&conn->connection_recovery))
4282 		iscsit_build_conn_drop_async_message(conn);
4283 
4284 	spin_unlock_bh(&sess->conn_lock);
4285 
4286 	/*
4287 	 * If connection reinstatement is being performed on this connection,
4288 	 * up the connection reinstatement semaphore that is being blocked on
4289 	 * in iscsit_cause_connection_reinstatement().
4290 	 */
4291 	spin_lock_bh(&conn->state_lock);
4292 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4293 		spin_unlock_bh(&conn->state_lock);
4294 		complete(&conn->conn_wait_comp);
4295 		wait_for_completion(&conn->conn_post_wait_comp);
4296 		spin_lock_bh(&conn->state_lock);
4297 	}
4298 
4299 	/*
4300 	 * If connection reinstatement is being performed on this connection
4301 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4302 	 * connection wait rcfr semaphore that is being blocked on
4303 	 * an iscsit_connection_reinstatement_rcfr().
4304 	 */
4305 	if (atomic_read(&conn->connection_wait_rcfr)) {
4306 		spin_unlock_bh(&conn->state_lock);
4307 		complete(&conn->conn_wait_rcfr_comp);
4308 		wait_for_completion(&conn->conn_post_wait_comp);
4309 		spin_lock_bh(&conn->state_lock);
4310 	}
4311 	atomic_set(&conn->connection_reinstatement, 1);
4312 	spin_unlock_bh(&conn->state_lock);
4313 
4314 	/*
4315 	 * If any other processes are accessing this connection pointer we
4316 	 * must wait until they have completed.
4317 	 */
4318 	iscsit_check_conn_usage_count(conn);
4319 
4320 	if (conn->conn_rx_hash.tfm)
4321 		crypto_free_hash(conn->conn_rx_hash.tfm);
4322 	if (conn->conn_tx_hash.tfm)
4323 		crypto_free_hash(conn->conn_tx_hash.tfm);
4324 
4325 	if (conn->conn_cpumask)
4326 		free_cpumask_var(conn->conn_cpumask);
4327 
4328 	kfree(conn->conn_ops);
4329 	conn->conn_ops = NULL;
4330 
4331 	if (conn->sock)
4332 		sock_release(conn->sock);
4333 
4334 	if (conn->conn_transport->iscsit_free_conn)
4335 		conn->conn_transport->iscsit_free_conn(conn);
4336 
4337 	iscsit_put_transport(conn->conn_transport);
4338 
4339 	conn->thread_set = NULL;
4340 
4341 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4342 	conn->conn_state = TARG_CONN_STATE_FREE;
4343 	kfree(conn);
4344 
4345 	spin_lock_bh(&sess->conn_lock);
4346 	atomic_dec(&sess->nconn);
4347 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4348 		" %s\n", atomic_read(&sess->nconn),
4349 		sess->sess_ops->InitiatorName);
4350 	/*
4351 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4352 	 * Session that they all fail.
4353 	 */
4354 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4355 	     !atomic_read(&sess->session_logout))
4356 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4357 
4358 	/*
4359 	 * If this was not the last connection in the session, and we are
4360 	 * performing session reinstatement or falling back to ERL=0, call
4361 	 * iscsit_stop_session() without sleeping to shutdown the other
4362 	 * active connections.
4363 	 */
4364 	if (atomic_read(&sess->nconn)) {
4365 		if (!atomic_read(&sess->session_reinstatement) &&
4366 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4367 			spin_unlock_bh(&sess->conn_lock);
4368 			return 0;
4369 		}
4370 		if (!atomic_read(&sess->session_stop_active)) {
4371 			atomic_set(&sess->session_stop_active, 1);
4372 			spin_unlock_bh(&sess->conn_lock);
4373 			iscsit_stop_session(sess, 0, 0);
4374 			return 0;
4375 		}
4376 		spin_unlock_bh(&sess->conn_lock);
4377 		return 0;
4378 	}
4379 
4380 	/*
4381 	 * If this was the last connection in the session and one of the
4382 	 * following is occurring:
4383 	 *
4384 	 * Session Reinstatement is not being performed, and are falling back
4385 	 * to ERL=0 call iscsit_close_session().
4386 	 *
4387 	 * Session Logout was requested.  iscsit_close_session() will be called
4388 	 * elsewhere.
4389 	 *
4390 	 * Session Continuation is not being performed, start the Time2Retain
4391 	 * handler and check if sleep_on_sess_wait_sem is active.
4392 	 */
4393 	if (!atomic_read(&sess->session_reinstatement) &&
4394 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4395 		spin_unlock_bh(&sess->conn_lock);
4396 		target_put_session(sess->se_sess);
4397 
4398 		return 0;
4399 	} else if (atomic_read(&sess->session_logout)) {
4400 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4401 		sess->session_state = TARG_SESS_STATE_FREE;
4402 		spin_unlock_bh(&sess->conn_lock);
4403 
4404 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4405 			complete(&sess->session_wait_comp);
4406 
4407 		return 0;
4408 	} else {
4409 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4410 		sess->session_state = TARG_SESS_STATE_FAILED;
4411 
4412 		if (!atomic_read(&sess->session_continuation)) {
4413 			spin_unlock_bh(&sess->conn_lock);
4414 			iscsit_start_time2retain_handler(sess);
4415 		} else
4416 			spin_unlock_bh(&sess->conn_lock);
4417 
4418 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4419 			complete(&sess->session_wait_comp);
4420 
4421 		return 0;
4422 	}
4423 	spin_unlock_bh(&sess->conn_lock);
4424 
4425 	return 0;
4426 }
4427 
4428 int iscsit_close_session(struct iscsi_session *sess)
4429 {
4430 	struct iscsi_portal_group *tpg = sess->tpg;
4431 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4432 
4433 	if (atomic_read(&sess->nconn)) {
4434 		pr_err("%d connection(s) still exist for iSCSI session"
4435 			" to %s\n", atomic_read(&sess->nconn),
4436 			sess->sess_ops->InitiatorName);
4437 		BUG();
4438 	}
4439 
4440 	spin_lock_bh(&se_tpg->session_lock);
4441 	atomic_set(&sess->session_logout, 1);
4442 	atomic_set(&sess->session_reinstatement, 1);
4443 	iscsit_stop_time2retain_timer(sess);
4444 	spin_unlock_bh(&se_tpg->session_lock);
4445 
4446 	/*
4447 	 * transport_deregister_session_configfs() will clear the
4448 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4449 	 * can be setting it again with __transport_register_session() in
4450 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4451 	 * completes in iscsi_np context.
4452 	 */
4453 	transport_deregister_session_configfs(sess->se_sess);
4454 
4455 	/*
4456 	 * If any other processes are accessing this session pointer we must
4457 	 * wait until they have completed.  If we are in an interrupt (the
4458 	 * time2retain handler) and contain and active session usage count we
4459 	 * restart the timer and exit.
4460 	 */
4461 	if (!in_interrupt()) {
4462 		if (iscsit_check_session_usage_count(sess) == 1)
4463 			iscsit_stop_session(sess, 1, 1);
4464 	} else {
4465 		if (iscsit_check_session_usage_count(sess) == 2) {
4466 			atomic_set(&sess->session_logout, 0);
4467 			iscsit_start_time2retain_handler(sess);
4468 			return 0;
4469 		}
4470 	}
4471 
4472 	transport_deregister_session(sess->se_sess);
4473 
4474 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4475 		iscsit_free_connection_recovery_entires(sess);
4476 
4477 	iscsit_free_all_ooo_cmdsns(sess);
4478 
4479 	spin_lock_bh(&se_tpg->session_lock);
4480 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4481 	sess->session_state = TARG_SESS_STATE_FREE;
4482 	pr_debug("Released iSCSI session from node: %s\n",
4483 			sess->sess_ops->InitiatorName);
4484 	tpg->nsessions--;
4485 	if (tpg->tpg_tiqn)
4486 		tpg->tpg_tiqn->tiqn_nsessions--;
4487 
4488 	pr_debug("Decremented number of active iSCSI Sessions on"
4489 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4490 
4491 	spin_lock(&sess_idr_lock);
4492 	idr_remove(&sess_idr, sess->session_index);
4493 	spin_unlock(&sess_idr_lock);
4494 
4495 	kfree(sess->sess_ops);
4496 	sess->sess_ops = NULL;
4497 	spin_unlock_bh(&se_tpg->session_lock);
4498 
4499 	kfree(sess);
4500 	return 0;
4501 }
4502 
4503 static void iscsit_logout_post_handler_closesession(
4504 	struct iscsi_conn *conn)
4505 {
4506 	struct iscsi_session *sess = conn->sess;
4507 
4508 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4509 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4510 
4511 	atomic_set(&conn->conn_logout_remove, 0);
4512 	complete(&conn->conn_logout_comp);
4513 
4514 	iscsit_dec_conn_usage_count(conn);
4515 	iscsit_stop_session(sess, 1, 1);
4516 	iscsit_dec_session_usage_count(sess);
4517 	target_put_session(sess->se_sess);
4518 }
4519 
4520 static void iscsit_logout_post_handler_samecid(
4521 	struct iscsi_conn *conn)
4522 {
4523 	iscsi_set_thread_clear(conn, ISCSI_CLEAR_TX_THREAD);
4524 	iscsi_set_thread_set_signal(conn, ISCSI_SIGNAL_TX_THREAD);
4525 
4526 	atomic_set(&conn->conn_logout_remove, 0);
4527 	complete(&conn->conn_logout_comp);
4528 
4529 	iscsit_cause_connection_reinstatement(conn, 1);
4530 	iscsit_dec_conn_usage_count(conn);
4531 }
4532 
4533 static void iscsit_logout_post_handler_diffcid(
4534 	struct iscsi_conn *conn,
4535 	u16 cid)
4536 {
4537 	struct iscsi_conn *l_conn;
4538 	struct iscsi_session *sess = conn->sess;
4539 
4540 	if (!sess)
4541 		return;
4542 
4543 	spin_lock_bh(&sess->conn_lock);
4544 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4545 		if (l_conn->cid == cid) {
4546 			iscsit_inc_conn_usage_count(l_conn);
4547 			break;
4548 		}
4549 	}
4550 	spin_unlock_bh(&sess->conn_lock);
4551 
4552 	if (!l_conn)
4553 		return;
4554 
4555 	if (l_conn->sock)
4556 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4557 
4558 	spin_lock_bh(&l_conn->state_lock);
4559 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4560 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4561 	spin_unlock_bh(&l_conn->state_lock);
4562 
4563 	iscsit_cause_connection_reinstatement(l_conn, 1);
4564 	iscsit_dec_conn_usage_count(l_conn);
4565 }
4566 
4567 /*
4568  *	Return of 0 causes the TX thread to restart.
4569  */
4570 int iscsit_logout_post_handler(
4571 	struct iscsi_cmd *cmd,
4572 	struct iscsi_conn *conn)
4573 {
4574 	int ret = 0;
4575 
4576 	switch (cmd->logout_reason) {
4577 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4578 		switch (cmd->logout_response) {
4579 		case ISCSI_LOGOUT_SUCCESS:
4580 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4581 		default:
4582 			iscsit_logout_post_handler_closesession(conn);
4583 			break;
4584 		}
4585 		ret = 0;
4586 		break;
4587 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4588 		if (conn->cid == cmd->logout_cid) {
4589 			switch (cmd->logout_response) {
4590 			case ISCSI_LOGOUT_SUCCESS:
4591 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4592 			default:
4593 				iscsit_logout_post_handler_samecid(conn);
4594 				break;
4595 			}
4596 			ret = 0;
4597 		} else {
4598 			switch (cmd->logout_response) {
4599 			case ISCSI_LOGOUT_SUCCESS:
4600 				iscsit_logout_post_handler_diffcid(conn,
4601 					cmd->logout_cid);
4602 				break;
4603 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4604 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4605 			default:
4606 				break;
4607 			}
4608 			ret = 1;
4609 		}
4610 		break;
4611 	case ISCSI_LOGOUT_REASON_RECOVERY:
4612 		switch (cmd->logout_response) {
4613 		case ISCSI_LOGOUT_SUCCESS:
4614 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4615 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4616 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4617 		default:
4618 			break;
4619 		}
4620 		ret = 1;
4621 		break;
4622 	default:
4623 		break;
4624 
4625 	}
4626 	return ret;
4627 }
4628 EXPORT_SYMBOL(iscsit_logout_post_handler);
4629 
4630 void iscsit_fail_session(struct iscsi_session *sess)
4631 {
4632 	struct iscsi_conn *conn;
4633 
4634 	spin_lock_bh(&sess->conn_lock);
4635 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4636 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4637 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4638 	}
4639 	spin_unlock_bh(&sess->conn_lock);
4640 
4641 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4642 	sess->session_state = TARG_SESS_STATE_FAILED;
4643 }
4644 
4645 int iscsit_free_session(struct iscsi_session *sess)
4646 {
4647 	u16 conn_count = atomic_read(&sess->nconn);
4648 	struct iscsi_conn *conn, *conn_tmp = NULL;
4649 	int is_last;
4650 
4651 	spin_lock_bh(&sess->conn_lock);
4652 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4653 
4654 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4655 			conn_list) {
4656 		if (conn_count == 0)
4657 			break;
4658 
4659 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4660 			is_last = 1;
4661 		} else {
4662 			iscsit_inc_conn_usage_count(conn_tmp);
4663 			is_last = 0;
4664 		}
4665 		iscsit_inc_conn_usage_count(conn);
4666 
4667 		spin_unlock_bh(&sess->conn_lock);
4668 		iscsit_cause_connection_reinstatement(conn, 1);
4669 		spin_lock_bh(&sess->conn_lock);
4670 
4671 		iscsit_dec_conn_usage_count(conn);
4672 		if (is_last == 0)
4673 			iscsit_dec_conn_usage_count(conn_tmp);
4674 
4675 		conn_count--;
4676 	}
4677 
4678 	if (atomic_read(&sess->nconn)) {
4679 		spin_unlock_bh(&sess->conn_lock);
4680 		wait_for_completion(&sess->session_wait_comp);
4681 	} else
4682 		spin_unlock_bh(&sess->conn_lock);
4683 
4684 	target_put_session(sess->se_sess);
4685 	return 0;
4686 }
4687 
4688 void iscsit_stop_session(
4689 	struct iscsi_session *sess,
4690 	int session_sleep,
4691 	int connection_sleep)
4692 {
4693 	u16 conn_count = atomic_read(&sess->nconn);
4694 	struct iscsi_conn *conn, *conn_tmp = NULL;
4695 	int is_last;
4696 
4697 	spin_lock_bh(&sess->conn_lock);
4698 	if (session_sleep)
4699 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4700 
4701 	if (connection_sleep) {
4702 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4703 				conn_list) {
4704 			if (conn_count == 0)
4705 				break;
4706 
4707 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4708 				is_last = 1;
4709 			} else {
4710 				iscsit_inc_conn_usage_count(conn_tmp);
4711 				is_last = 0;
4712 			}
4713 			iscsit_inc_conn_usage_count(conn);
4714 
4715 			spin_unlock_bh(&sess->conn_lock);
4716 			iscsit_cause_connection_reinstatement(conn, 1);
4717 			spin_lock_bh(&sess->conn_lock);
4718 
4719 			iscsit_dec_conn_usage_count(conn);
4720 			if (is_last == 0)
4721 				iscsit_dec_conn_usage_count(conn_tmp);
4722 			conn_count--;
4723 		}
4724 	} else {
4725 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4726 			iscsit_cause_connection_reinstatement(conn, 0);
4727 	}
4728 
4729 	if (session_sleep && atomic_read(&sess->nconn)) {
4730 		spin_unlock_bh(&sess->conn_lock);
4731 		wait_for_completion(&sess->session_wait_comp);
4732 	} else
4733 		spin_unlock_bh(&sess->conn_lock);
4734 }
4735 
4736 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4737 {
4738 	struct iscsi_session *sess;
4739 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4740 	struct se_session *se_sess, *se_sess_tmp;
4741 	int session_count = 0;
4742 
4743 	spin_lock_bh(&se_tpg->session_lock);
4744 	if (tpg->nsessions && !force) {
4745 		spin_unlock_bh(&se_tpg->session_lock);
4746 		return -1;
4747 	}
4748 
4749 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4750 			sess_list) {
4751 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4752 
4753 		spin_lock(&sess->conn_lock);
4754 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4755 		    atomic_read(&sess->session_logout) ||
4756 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4757 			spin_unlock(&sess->conn_lock);
4758 			continue;
4759 		}
4760 		atomic_set(&sess->session_reinstatement, 1);
4761 		spin_unlock(&sess->conn_lock);
4762 		spin_unlock_bh(&se_tpg->session_lock);
4763 
4764 		iscsit_free_session(sess);
4765 		spin_lock_bh(&se_tpg->session_lock);
4766 
4767 		session_count++;
4768 	}
4769 	spin_unlock_bh(&se_tpg->session_lock);
4770 
4771 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4772 			" Group: %hu\n", session_count, tpg->tpgt);
4773 	return 0;
4774 }
4775 
4776 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4777 MODULE_VERSION("4.1.x");
4778 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4779 MODULE_LICENSE("GPL");
4780 
4781 module_init(iscsi_target_init_module);
4782 module_exit(iscsi_target_cleanup_module);
4783