1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18 
19 #include <crypto/hash.h>
20 #include <linux/string.h>
21 #include <linux/kthread.h>
22 #include <linux/completion.h>
23 #include <linux/module.h>
24 #include <linux/vmalloc.h>
25 #include <linux/idr.h>
26 #include <linux/delay.h>
27 #include <linux/sched/signal.h>
28 #include <asm/unaligned.h>
29 #include <linux/inet.h>
30 #include <net/ipv6.h>
31 #include <scsi/scsi_proto.h>
32 #include <scsi/iscsi_proto.h>
33 #include <scsi/scsi_tcq.h>
34 #include <target/target_core_base.h>
35 #include <target/target_core_fabric.h>
36 
37 #include <target/iscsi/iscsi_target_core.h>
38 #include "iscsi_target_parameters.h"
39 #include "iscsi_target_seq_pdu_list.h"
40 #include "iscsi_target_datain_values.h"
41 #include "iscsi_target_erl0.h"
42 #include "iscsi_target_erl1.h"
43 #include "iscsi_target_erl2.h"
44 #include "iscsi_target_login.h"
45 #include "iscsi_target_tmr.h"
46 #include "iscsi_target_tpg.h"
47 #include "iscsi_target_util.h"
48 #include "iscsi_target.h"
49 #include "iscsi_target_device.h"
50 #include <target/iscsi/iscsi_target_stat.h>
51 
52 #include <target/iscsi/iscsi_transport.h>
53 
54 static LIST_HEAD(g_tiqn_list);
55 static LIST_HEAD(g_np_list);
56 static DEFINE_SPINLOCK(tiqn_lock);
57 static DEFINE_MUTEX(np_lock);
58 
59 static struct idr tiqn_idr;
60 DEFINE_IDA(sess_ida);
61 struct mutex auth_id_lock;
62 
63 struct iscsit_global *iscsit_global;
64 
65 struct kmem_cache *lio_qr_cache;
66 struct kmem_cache *lio_dr_cache;
67 struct kmem_cache *lio_ooo_cache;
68 struct kmem_cache *lio_r2t_cache;
69 
70 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
71 			struct iscsi_scsi_req *, u32);
72 
73 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
74 {
75 	struct iscsi_tiqn *tiqn = NULL;
76 
77 	spin_lock(&tiqn_lock);
78 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
79 		if (!strcmp(tiqn->tiqn, buf)) {
80 
81 			spin_lock(&tiqn->tiqn_state_lock);
82 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
83 				tiqn->tiqn_access_count++;
84 				spin_unlock(&tiqn->tiqn_state_lock);
85 				spin_unlock(&tiqn_lock);
86 				return tiqn;
87 			}
88 			spin_unlock(&tiqn->tiqn_state_lock);
89 		}
90 	}
91 	spin_unlock(&tiqn_lock);
92 
93 	return NULL;
94 }
95 
96 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
97 {
98 	spin_lock(&tiqn->tiqn_state_lock);
99 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
100 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
101 		spin_unlock(&tiqn->tiqn_state_lock);
102 		return 0;
103 	}
104 	spin_unlock(&tiqn->tiqn_state_lock);
105 
106 	return -1;
107 }
108 
109 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
110 {
111 	spin_lock(&tiqn->tiqn_state_lock);
112 	tiqn->tiqn_access_count--;
113 	spin_unlock(&tiqn->tiqn_state_lock);
114 }
115 
116 /*
117  * Note that IQN formatting is expected to be done in userspace, and
118  * no explict IQN format checks are done here.
119  */
120 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
121 {
122 	struct iscsi_tiqn *tiqn = NULL;
123 	int ret;
124 
125 	if (strlen(buf) >= ISCSI_IQN_LEN) {
126 		pr_err("Target IQN exceeds %d bytes\n",
127 				ISCSI_IQN_LEN);
128 		return ERR_PTR(-EINVAL);
129 	}
130 
131 	tiqn = kzalloc(sizeof(*tiqn), GFP_KERNEL);
132 	if (!tiqn)
133 		return ERR_PTR(-ENOMEM);
134 
135 	sprintf(tiqn->tiqn, "%s", buf);
136 	INIT_LIST_HEAD(&tiqn->tiqn_list);
137 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
138 	spin_lock_init(&tiqn->tiqn_state_lock);
139 	spin_lock_init(&tiqn->tiqn_tpg_lock);
140 	spin_lock_init(&tiqn->sess_err_stats.lock);
141 	spin_lock_init(&tiqn->login_stats.lock);
142 	spin_lock_init(&tiqn->logout_stats.lock);
143 
144 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
145 
146 	idr_preload(GFP_KERNEL);
147 	spin_lock(&tiqn_lock);
148 
149 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
150 	if (ret < 0) {
151 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
152 		spin_unlock(&tiqn_lock);
153 		idr_preload_end();
154 		kfree(tiqn);
155 		return ERR_PTR(ret);
156 	}
157 	tiqn->tiqn_index = ret;
158 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
159 
160 	spin_unlock(&tiqn_lock);
161 	idr_preload_end();
162 
163 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
164 
165 	return tiqn;
166 
167 }
168 
169 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
170 {
171 	/*
172 	 * Wait for accesses to said struct iscsi_tiqn to end.
173 	 */
174 	spin_lock(&tiqn->tiqn_state_lock);
175 	while (tiqn->tiqn_access_count != 0) {
176 		spin_unlock(&tiqn->tiqn_state_lock);
177 		msleep(10);
178 		spin_lock(&tiqn->tiqn_state_lock);
179 	}
180 	spin_unlock(&tiqn->tiqn_state_lock);
181 }
182 
183 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
184 {
185 	/*
186 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
187 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
188 	 * attempts to access this struct iscsi_tiqn will fail from both transport
189 	 * fabric and control code paths.
190 	 */
191 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
192 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
193 		return;
194 	}
195 
196 	iscsit_wait_for_tiqn(tiqn);
197 
198 	spin_lock(&tiqn_lock);
199 	list_del(&tiqn->tiqn_list);
200 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
201 	spin_unlock(&tiqn_lock);
202 
203 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
204 			tiqn->tiqn);
205 	kfree(tiqn);
206 }
207 
208 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
209 {
210 	int ret;
211 	/*
212 	 * Determine if the network portal is accepting storage traffic.
213 	 */
214 	spin_lock_bh(&np->np_thread_lock);
215 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
216 		spin_unlock_bh(&np->np_thread_lock);
217 		return -1;
218 	}
219 	spin_unlock_bh(&np->np_thread_lock);
220 	/*
221 	 * Determine if the portal group is accepting storage traffic.
222 	 */
223 	spin_lock_bh(&tpg->tpg_state_lock);
224 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
225 		spin_unlock_bh(&tpg->tpg_state_lock);
226 		return -1;
227 	}
228 	spin_unlock_bh(&tpg->tpg_state_lock);
229 
230 	/*
231 	 * Here we serialize access across the TIQN+TPG Tuple.
232 	 */
233 	ret = down_interruptible(&tpg->np_login_sem);
234 	if (ret != 0)
235 		return -1;
236 
237 	spin_lock_bh(&tpg->tpg_state_lock);
238 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
239 		spin_unlock_bh(&tpg->tpg_state_lock);
240 		up(&tpg->np_login_sem);
241 		return -1;
242 	}
243 	spin_unlock_bh(&tpg->tpg_state_lock);
244 
245 	return 0;
246 }
247 
248 void iscsit_login_kref_put(struct kref *kref)
249 {
250 	struct iscsi_tpg_np *tpg_np = container_of(kref,
251 				struct iscsi_tpg_np, tpg_np_kref);
252 
253 	complete(&tpg_np->tpg_np_comp);
254 }
255 
256 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
257 		       struct iscsi_tpg_np *tpg_np)
258 {
259 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
260 
261 	up(&tpg->np_login_sem);
262 
263 	if (tpg_np)
264 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
265 
266 	if (tiqn)
267 		iscsit_put_tiqn_for_login(tiqn);
268 
269 	return 0;
270 }
271 
272 bool iscsit_check_np_match(
273 	struct sockaddr_storage *sockaddr,
274 	struct iscsi_np *np,
275 	int network_transport)
276 {
277 	struct sockaddr_in *sock_in, *sock_in_e;
278 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
279 	bool ip_match = false;
280 	u16 port, port_e;
281 
282 	if (sockaddr->ss_family == AF_INET6) {
283 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
284 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
285 
286 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
287 			    &sock_in6_e->sin6_addr.in6_u,
288 			    sizeof(struct in6_addr)))
289 			ip_match = true;
290 
291 		port = ntohs(sock_in6->sin6_port);
292 		port_e = ntohs(sock_in6_e->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 		port_e = ntohs(sock_in_e->sin_port);
302 	}
303 
304 	if (ip_match && (port_e == port) &&
305 	    (np->np_network_transport == network_transport))
306 		return true;
307 
308 	return false;
309 }
310 
311 static struct iscsi_np *iscsit_get_np(
312 	struct sockaddr_storage *sockaddr,
313 	int network_transport)
314 {
315 	struct iscsi_np *np;
316 	bool match;
317 
318 	lockdep_assert_held(&np_lock);
319 
320 	list_for_each_entry(np, &g_np_list, np_list) {
321 		spin_lock_bh(&np->np_thread_lock);
322 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
323 			spin_unlock_bh(&np->np_thread_lock);
324 			continue;
325 		}
326 
327 		match = iscsit_check_np_match(sockaddr, np, network_transport);
328 		if (match) {
329 			/*
330 			 * Increment the np_exports reference count now to
331 			 * prevent iscsit_del_np() below from being called
332 			 * while iscsi_tpg_add_network_portal() is called.
333 			 */
334 			np->np_exports++;
335 			spin_unlock_bh(&np->np_thread_lock);
336 			return np;
337 		}
338 		spin_unlock_bh(&np->np_thread_lock);
339 	}
340 
341 	return NULL;
342 }
343 
344 struct iscsi_np *iscsit_add_np(
345 	struct sockaddr_storage *sockaddr,
346 	int network_transport)
347 {
348 	struct iscsi_np *np;
349 	int ret;
350 
351 	mutex_lock(&np_lock);
352 
353 	/*
354 	 * Locate the existing struct iscsi_np if already active..
355 	 */
356 	np = iscsit_get_np(sockaddr, network_transport);
357 	if (np) {
358 		mutex_unlock(&np_lock);
359 		return np;
360 	}
361 
362 	np = kzalloc(sizeof(*np), GFP_KERNEL);
363 	if (!np) {
364 		mutex_unlock(&np_lock);
365 		return ERR_PTR(-ENOMEM);
366 	}
367 
368 	np->np_flags |= NPF_IP_NETWORK;
369 	np->np_network_transport = network_transport;
370 	spin_lock_init(&np->np_thread_lock);
371 	init_completion(&np->np_restart_comp);
372 	INIT_LIST_HEAD(&np->np_list);
373 
374 	timer_setup(&np->np_login_timer, iscsi_handle_login_thread_timeout, 0);
375 
376 	ret = iscsi_target_setup_login_socket(np, sockaddr);
377 	if (ret != 0) {
378 		kfree(np);
379 		mutex_unlock(&np_lock);
380 		return ERR_PTR(ret);
381 	}
382 
383 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
384 	if (IS_ERR(np->np_thread)) {
385 		pr_err("Unable to create kthread: iscsi_np\n");
386 		ret = PTR_ERR(np->np_thread);
387 		kfree(np);
388 		mutex_unlock(&np_lock);
389 		return ERR_PTR(ret);
390 	}
391 	/*
392 	 * Increment the np_exports reference count now to prevent
393 	 * iscsit_del_np() below from being run while a new call to
394 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
395 	 * active.  We don't need to hold np->np_thread_lock at this
396 	 * point because iscsi_np has not been added to g_np_list yet.
397 	 */
398 	np->np_exports = 1;
399 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
400 
401 	list_add_tail(&np->np_list, &g_np_list);
402 	mutex_unlock(&np_lock);
403 
404 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
405 		&np->np_sockaddr, np->np_transport->name);
406 
407 	return np;
408 }
409 
410 int iscsit_reset_np_thread(
411 	struct iscsi_np *np,
412 	struct iscsi_tpg_np *tpg_np,
413 	struct iscsi_portal_group *tpg,
414 	bool shutdown)
415 {
416 	spin_lock_bh(&np->np_thread_lock);
417 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
418 		spin_unlock_bh(&np->np_thread_lock);
419 		return 0;
420 	}
421 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
422 	atomic_inc(&np->np_reset_count);
423 
424 	if (np->np_thread) {
425 		spin_unlock_bh(&np->np_thread_lock);
426 		send_sig(SIGINT, np->np_thread, 1);
427 		wait_for_completion(&np->np_restart_comp);
428 		spin_lock_bh(&np->np_thread_lock);
429 	}
430 	spin_unlock_bh(&np->np_thread_lock);
431 
432 	if (tpg_np && shutdown) {
433 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
434 
435 		wait_for_completion(&tpg_np->tpg_np_comp);
436 	}
437 
438 	return 0;
439 }
440 
441 static void iscsit_free_np(struct iscsi_np *np)
442 {
443 	if (np->np_socket)
444 		sock_release(np->np_socket);
445 }
446 
447 int iscsit_del_np(struct iscsi_np *np)
448 {
449 	spin_lock_bh(&np->np_thread_lock);
450 	np->np_exports--;
451 	if (np->np_exports) {
452 		np->enabled = true;
453 		spin_unlock_bh(&np->np_thread_lock);
454 		return 0;
455 	}
456 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
457 	spin_unlock_bh(&np->np_thread_lock);
458 
459 	if (np->np_thread) {
460 		/*
461 		 * We need to send the signal to wakeup Linux/Net
462 		 * which may be sleeping in sock_accept()..
463 		 */
464 		send_sig(SIGINT, np->np_thread, 1);
465 		kthread_stop(np->np_thread);
466 		np->np_thread = NULL;
467 	}
468 
469 	np->np_transport->iscsit_free_np(np);
470 
471 	mutex_lock(&np_lock);
472 	list_del(&np->np_list);
473 	mutex_unlock(&np_lock);
474 
475 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
476 		&np->np_sockaddr, np->np_transport->name);
477 
478 	iscsit_put_transport(np->np_transport);
479 	kfree(np);
480 	return 0;
481 }
482 
483 static void iscsit_get_rx_pdu(struct iscsi_conn *);
484 
485 int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
486 {
487 	return iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
488 }
489 EXPORT_SYMBOL(iscsit_queue_rsp);
490 
491 void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
492 {
493 	spin_lock_bh(&conn->cmd_lock);
494 	if (!list_empty(&cmd->i_conn_node) &&
495 	    !(cmd->se_cmd.transport_state & CMD_T_FABRIC_STOP))
496 		list_del_init(&cmd->i_conn_node);
497 	spin_unlock_bh(&conn->cmd_lock);
498 
499 	__iscsit_free_cmd(cmd, true);
500 }
501 EXPORT_SYMBOL(iscsit_aborted_task);
502 
503 static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
504 				      u32, u32, const void *, void *);
505 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *);
506 
507 static int
508 iscsit_xmit_nondatain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
509 			  const void *data_buf, u32 data_buf_len)
510 {
511 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
512 	struct kvec *iov;
513 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
514 	int ret;
515 
516 	iov = &cmd->iov_misc[0];
517 	iov[niov].iov_base	= cmd->pdu;
518 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
519 
520 	if (conn->conn_ops->HeaderDigest) {
521 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
522 
523 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
524 					  ISCSI_HDR_LEN, 0, NULL,
525 					  header_digest);
526 
527 		iov[0].iov_len += ISCSI_CRC_LEN;
528 		tx_size += ISCSI_CRC_LEN;
529 		pr_debug("Attaching CRC32C HeaderDigest"
530 			 " to opcode 0x%x 0x%08x\n",
531 			 hdr->opcode, *header_digest);
532 	}
533 
534 	if (data_buf_len) {
535 		u32 padding = ((-data_buf_len) & 3);
536 
537 		iov[niov].iov_base	= (void *)data_buf;
538 		iov[niov++].iov_len	= data_buf_len;
539 		tx_size += data_buf_len;
540 
541 		if (padding != 0) {
542 			iov[niov].iov_base = &cmd->pad_bytes;
543 			iov[niov++].iov_len = padding;
544 			tx_size += padding;
545 			pr_debug("Attaching %u additional"
546 				 " padding bytes.\n", padding);
547 		}
548 
549 		if (conn->conn_ops->DataDigest) {
550 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
551 						  data_buf, data_buf_len,
552 						  padding, &cmd->pad_bytes,
553 						  &cmd->data_crc);
554 
555 			iov[niov].iov_base = &cmd->data_crc;
556 			iov[niov++].iov_len = ISCSI_CRC_LEN;
557 			tx_size += ISCSI_CRC_LEN;
558 			pr_debug("Attached DataDigest for %u"
559 				 " bytes opcode 0x%x, CRC 0x%08x\n",
560 				 data_buf_len, hdr->opcode, cmd->data_crc);
561 		}
562 	}
563 
564 	cmd->iov_misc_count = niov;
565 	cmd->tx_size = tx_size;
566 
567 	ret = iscsit_send_tx_data(cmd, conn, 1);
568 	if (ret < 0) {
569 		iscsit_tx_thread_wait_for_tcp(conn);
570 		return ret;
571 	}
572 
573 	return 0;
574 }
575 
576 static int iscsit_map_iovec(struct iscsi_cmd *, struct kvec *, u32, u32);
577 static void iscsit_unmap_iovec(struct iscsi_cmd *);
578 static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsi_cmd *,
579 				    u32, u32, u32, u8 *);
580 static int
581 iscsit_xmit_datain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
582 		       const struct iscsi_datain *datain)
583 {
584 	struct kvec *iov;
585 	u32 iov_count = 0, tx_size = 0;
586 	int ret, iov_ret;
587 
588 	iov = &cmd->iov_data[0];
589 	iov[iov_count].iov_base	= cmd->pdu;
590 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
591 	tx_size += ISCSI_HDR_LEN;
592 
593 	if (conn->conn_ops->HeaderDigest) {
594 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
595 
596 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
597 					  ISCSI_HDR_LEN, 0, NULL,
598 					  header_digest);
599 
600 		iov[0].iov_len += ISCSI_CRC_LEN;
601 		tx_size += ISCSI_CRC_LEN;
602 
603 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
604 			 *header_digest);
605 	}
606 
607 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
608 				   datain->offset, datain->length);
609 	if (iov_ret < 0)
610 		return -1;
611 
612 	iov_count += iov_ret;
613 	tx_size += datain->length;
614 
615 	cmd->padding = ((-datain->length) & 3);
616 	if (cmd->padding) {
617 		iov[iov_count].iov_base		= cmd->pad_bytes;
618 		iov[iov_count++].iov_len	= cmd->padding;
619 		tx_size += cmd->padding;
620 
621 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
622 	}
623 
624 	if (conn->conn_ops->DataDigest) {
625 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
626 							 cmd, datain->offset,
627 							 datain->length,
628 							 cmd->padding,
629 							 cmd->pad_bytes);
630 
631 		iov[iov_count].iov_base	= &cmd->data_crc;
632 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
633 		tx_size += ISCSI_CRC_LEN;
634 
635 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
636 			 datain->length + cmd->padding, cmd->data_crc);
637 	}
638 
639 	cmd->iov_data_count = iov_count;
640 	cmd->tx_size = tx_size;
641 
642 	ret = iscsit_fe_sendpage_sg(cmd, conn);
643 
644 	iscsit_unmap_iovec(cmd);
645 
646 	if (ret < 0) {
647 		iscsit_tx_thread_wait_for_tcp(conn);
648 		return ret;
649 	}
650 
651 	return 0;
652 }
653 
654 static int iscsit_xmit_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
655 			   struct iscsi_datain_req *dr, const void *buf,
656 			   u32 buf_len)
657 {
658 	if (dr)
659 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
660 	else
661 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
662 }
663 
664 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
665 {
666 	return TARGET_PROT_NORMAL;
667 }
668 
669 static struct iscsit_transport iscsi_target_transport = {
670 	.name			= "iSCSI/TCP",
671 	.transport_type		= ISCSI_TCP,
672 	.rdma_shutdown		= false,
673 	.owner			= NULL,
674 	.iscsit_setup_np	= iscsit_setup_np,
675 	.iscsit_accept_np	= iscsit_accept_np,
676 	.iscsit_free_np		= iscsit_free_np,
677 	.iscsit_get_login_rx	= iscsit_get_login_rx,
678 	.iscsit_put_login_tx	= iscsit_put_login_tx,
679 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
680 	.iscsit_immediate_queue	= iscsit_immediate_queue,
681 	.iscsit_response_queue	= iscsit_response_queue,
682 	.iscsit_queue_data_in	= iscsit_queue_rsp,
683 	.iscsit_queue_status	= iscsit_queue_rsp,
684 	.iscsit_aborted_task	= iscsit_aborted_task,
685 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
686 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
687 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
688 };
689 
690 static int __init iscsi_target_init_module(void)
691 {
692 	int ret = 0, size;
693 
694 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
695 	iscsit_global = kzalloc(sizeof(*iscsit_global), GFP_KERNEL);
696 	if (!iscsit_global)
697 		return -1;
698 
699 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
700 	mutex_init(&auth_id_lock);
701 	idr_init(&tiqn_idr);
702 
703 	ret = target_register_template(&iscsi_ops);
704 	if (ret)
705 		goto out;
706 
707 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
708 	iscsit_global->ts_bitmap = vzalloc(size);
709 	if (!iscsit_global->ts_bitmap)
710 		goto configfs_out;
711 
712 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
713 			sizeof(struct iscsi_queue_req),
714 			__alignof__(struct iscsi_queue_req), 0, NULL);
715 	if (!lio_qr_cache) {
716 		pr_err("Unable to kmem_cache_create() for"
717 				" lio_qr_cache\n");
718 		goto bitmap_out;
719 	}
720 
721 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
722 			sizeof(struct iscsi_datain_req),
723 			__alignof__(struct iscsi_datain_req), 0, NULL);
724 	if (!lio_dr_cache) {
725 		pr_err("Unable to kmem_cache_create() for"
726 				" lio_dr_cache\n");
727 		goto qr_out;
728 	}
729 
730 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
731 			sizeof(struct iscsi_ooo_cmdsn),
732 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
733 	if (!lio_ooo_cache) {
734 		pr_err("Unable to kmem_cache_create() for"
735 				" lio_ooo_cache\n");
736 		goto dr_out;
737 	}
738 
739 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
740 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
741 			0, NULL);
742 	if (!lio_r2t_cache) {
743 		pr_err("Unable to kmem_cache_create() for"
744 				" lio_r2t_cache\n");
745 		goto ooo_out;
746 	}
747 
748 	iscsit_register_transport(&iscsi_target_transport);
749 
750 	if (iscsit_load_discovery_tpg() < 0)
751 		goto r2t_out;
752 
753 	return ret;
754 r2t_out:
755 	iscsit_unregister_transport(&iscsi_target_transport);
756 	kmem_cache_destroy(lio_r2t_cache);
757 ooo_out:
758 	kmem_cache_destroy(lio_ooo_cache);
759 dr_out:
760 	kmem_cache_destroy(lio_dr_cache);
761 qr_out:
762 	kmem_cache_destroy(lio_qr_cache);
763 bitmap_out:
764 	vfree(iscsit_global->ts_bitmap);
765 configfs_out:
766 	/* XXX: this probably wants it to be it's own unwind step.. */
767 	if (iscsit_global->discovery_tpg)
768 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
769 	target_unregister_template(&iscsi_ops);
770 out:
771 	kfree(iscsit_global);
772 	return -ENOMEM;
773 }
774 
775 static void __exit iscsi_target_cleanup_module(void)
776 {
777 	iscsit_release_discovery_tpg();
778 	iscsit_unregister_transport(&iscsi_target_transport);
779 	kmem_cache_destroy(lio_qr_cache);
780 	kmem_cache_destroy(lio_dr_cache);
781 	kmem_cache_destroy(lio_ooo_cache);
782 	kmem_cache_destroy(lio_r2t_cache);
783 
784 	/*
785 	 * Shutdown discovery sessions and disable discovery TPG
786 	 */
787 	if (iscsit_global->discovery_tpg)
788 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
789 
790 	target_unregister_template(&iscsi_ops);
791 
792 	vfree(iscsit_global->ts_bitmap);
793 	kfree(iscsit_global);
794 }
795 
796 int iscsit_add_reject(
797 	struct iscsi_conn *conn,
798 	u8 reason,
799 	unsigned char *buf)
800 {
801 	struct iscsi_cmd *cmd;
802 
803 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
804 	if (!cmd)
805 		return -1;
806 
807 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
808 	cmd->reject_reason = reason;
809 
810 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
811 	if (!cmd->buf_ptr) {
812 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
813 		iscsit_free_cmd(cmd, false);
814 		return -1;
815 	}
816 
817 	spin_lock_bh(&conn->cmd_lock);
818 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
819 	spin_unlock_bh(&conn->cmd_lock);
820 
821 	cmd->i_state = ISTATE_SEND_REJECT;
822 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
823 
824 	return -1;
825 }
826 EXPORT_SYMBOL(iscsit_add_reject);
827 
828 static int iscsit_add_reject_from_cmd(
829 	struct iscsi_cmd *cmd,
830 	u8 reason,
831 	bool add_to_conn,
832 	unsigned char *buf)
833 {
834 	struct iscsi_conn *conn;
835 	const bool do_put = cmd->se_cmd.se_tfo != NULL;
836 
837 	if (!cmd->conn) {
838 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
839 				cmd->init_task_tag);
840 		return -1;
841 	}
842 	conn = cmd->conn;
843 
844 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
845 	cmd->reject_reason = reason;
846 
847 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
848 	if (!cmd->buf_ptr) {
849 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
850 		iscsit_free_cmd(cmd, false);
851 		return -1;
852 	}
853 
854 	if (add_to_conn) {
855 		spin_lock_bh(&conn->cmd_lock);
856 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
857 		spin_unlock_bh(&conn->cmd_lock);
858 	}
859 
860 	cmd->i_state = ISTATE_SEND_REJECT;
861 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
862 	/*
863 	 * Perform the kref_put now if se_cmd has already been setup by
864 	 * scsit_setup_scsi_cmd()
865 	 */
866 	if (do_put) {
867 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
868 		target_put_sess_cmd(&cmd->se_cmd);
869 	}
870 	return -1;
871 }
872 
873 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
874 				 unsigned char *buf)
875 {
876 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
877 }
878 
879 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
880 {
881 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
882 }
883 EXPORT_SYMBOL(iscsit_reject_cmd);
884 
885 /*
886  * Map some portion of the allocated scatterlist to an iovec, suitable for
887  * kernel sockets to copy data in/out.
888  */
889 static int iscsit_map_iovec(
890 	struct iscsi_cmd *cmd,
891 	struct kvec *iov,
892 	u32 data_offset,
893 	u32 data_length)
894 {
895 	u32 i = 0;
896 	struct scatterlist *sg;
897 	unsigned int page_off;
898 
899 	/*
900 	 * We know each entry in t_data_sg contains a page.
901 	 */
902 	u32 ent = data_offset / PAGE_SIZE;
903 
904 	if (ent >= cmd->se_cmd.t_data_nents) {
905 		pr_err("Initial page entry out-of-bounds\n");
906 		return -1;
907 	}
908 
909 	sg = &cmd->se_cmd.t_data_sg[ent];
910 	page_off = (data_offset % PAGE_SIZE);
911 
912 	cmd->first_data_sg = sg;
913 	cmd->first_data_sg_off = page_off;
914 
915 	while (data_length) {
916 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
917 
918 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
919 		iov[i].iov_len = cur_len;
920 
921 		data_length -= cur_len;
922 		page_off = 0;
923 		sg = sg_next(sg);
924 		i++;
925 	}
926 
927 	cmd->kmapped_nents = i;
928 
929 	return i;
930 }
931 
932 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
933 {
934 	u32 i;
935 	struct scatterlist *sg;
936 
937 	sg = cmd->first_data_sg;
938 
939 	for (i = 0; i < cmd->kmapped_nents; i++)
940 		kunmap(sg_page(&sg[i]));
941 }
942 
943 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
944 {
945 	LIST_HEAD(ack_list);
946 	struct iscsi_cmd *cmd, *cmd_p;
947 
948 	conn->exp_statsn = exp_statsn;
949 
950 	if (conn->sess->sess_ops->RDMAExtensions)
951 		return;
952 
953 	spin_lock_bh(&conn->cmd_lock);
954 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
955 		spin_lock(&cmd->istate_lock);
956 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
957 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
958 			cmd->i_state = ISTATE_REMOVE;
959 			spin_unlock(&cmd->istate_lock);
960 			list_move_tail(&cmd->i_conn_node, &ack_list);
961 			continue;
962 		}
963 		spin_unlock(&cmd->istate_lock);
964 	}
965 	spin_unlock_bh(&conn->cmd_lock);
966 
967 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
968 		list_del_init(&cmd->i_conn_node);
969 		iscsit_free_cmd(cmd, false);
970 	}
971 }
972 
973 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
974 {
975 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
976 
977 	iov_count += ISCSI_IOV_DATA_BUFFER;
978 	cmd->iov_data = kcalloc(iov_count, sizeof(*cmd->iov_data), GFP_KERNEL);
979 	if (!cmd->iov_data)
980 		return -ENOMEM;
981 
982 	cmd->orig_iov_data_count = iov_count;
983 	return 0;
984 }
985 
986 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
987 			  unsigned char *buf)
988 {
989 	int data_direction, payload_length;
990 	struct iscsi_scsi_req *hdr;
991 	int iscsi_task_attr;
992 	int sam_task_attr;
993 
994 	atomic_long_inc(&conn->sess->cmd_pdus);
995 
996 	hdr			= (struct iscsi_scsi_req *) buf;
997 	payload_length		= ntoh24(hdr->dlength);
998 
999 	/* FIXME; Add checks for AdditionalHeaderSegment */
1000 
1001 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1002 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1003 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1004 				" not set. Bad iSCSI Initiator.\n");
1005 		return iscsit_add_reject_cmd(cmd,
1006 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1007 	}
1008 
1009 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1010 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1011 		/*
1012 		 * From RFC-3720 Section 10.3.1:
1013 		 *
1014 		 * "Either or both of R and W MAY be 1 when either the
1015 		 *  Expected Data Transfer Length and/or Bidirectional Read
1016 		 *  Expected Data Transfer Length are 0"
1017 		 *
1018 		 * For this case, go ahead and clear the unnecssary bits
1019 		 * to avoid any confusion with ->data_direction.
1020 		 */
1021 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1022 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1023 
1024 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1025 			" set when Expected Data Transfer Length is 0 for"
1026 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1027 	}
1028 
1029 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1030 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1031 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1032 			" MUST be set if Expected Data Transfer Length is not 0."
1033 			" Bad iSCSI Initiator\n");
1034 		return iscsit_add_reject_cmd(cmd,
1035 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1036 	}
1037 
1038 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1039 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1040 		pr_err("Bidirectional operations not supported!\n");
1041 		return iscsit_add_reject_cmd(cmd,
1042 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1043 	}
1044 
1045 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1046 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1047 				" Scsi Command PDU.\n");
1048 		return iscsit_add_reject_cmd(cmd,
1049 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1050 	}
1051 
1052 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1053 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1054 			" protocol error.\n", payload_length);
1055 		return iscsit_add_reject_cmd(cmd,
1056 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1057 	}
1058 
1059 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1060 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1061 		pr_err("Expected Data Transfer Length and Length of"
1062 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1063 			" bit is not set protocol error\n");
1064 		return iscsit_add_reject_cmd(cmd,
1065 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1066 	}
1067 
1068 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1069 		pr_err("DataSegmentLength: %u is greater than"
1070 			" EDTL: %u, protocol error.\n", payload_length,
1071 				hdr->data_length);
1072 		return iscsit_add_reject_cmd(cmd,
1073 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1074 	}
1075 
1076 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1077 		pr_err("DataSegmentLength: %u is greater than"
1078 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1079 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1080 		return iscsit_add_reject_cmd(cmd,
1081 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1082 	}
1083 
1084 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1085 		pr_err("DataSegmentLength: %u is greater than"
1086 			" FirstBurstLength: %u, protocol error.\n",
1087 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1088 		return iscsit_add_reject_cmd(cmd,
1089 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1090 	}
1091 
1092 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1093 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1094 			  DMA_NONE;
1095 
1096 	cmd->data_direction = data_direction;
1097 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1098 	/*
1099 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1100 	 */
1101 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1102 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1103 		sam_task_attr = TCM_SIMPLE_TAG;
1104 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1105 		sam_task_attr = TCM_ORDERED_TAG;
1106 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1107 		sam_task_attr = TCM_HEAD_TAG;
1108 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1109 		sam_task_attr = TCM_ACA_TAG;
1110 	else {
1111 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1112 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1113 		sam_task_attr = TCM_SIMPLE_TAG;
1114 	}
1115 
1116 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1117 	cmd->i_state		= ISTATE_NEW_CMD;
1118 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1119 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1120 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1121 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1122 	if (cmd->unsolicited_data)
1123 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1124 
1125 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1126 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1127 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1128 	else
1129 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1130 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1131 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1132 	cmd->first_burst_len	= payload_length;
1133 
1134 	if (!conn->sess->sess_ops->RDMAExtensions &&
1135 	     cmd->data_direction == DMA_FROM_DEVICE) {
1136 		struct iscsi_datain_req *dr;
1137 
1138 		dr = iscsit_allocate_datain_req();
1139 		if (!dr)
1140 			return iscsit_add_reject_cmd(cmd,
1141 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1142 
1143 		iscsit_attach_datain_req(cmd, dr);
1144 	}
1145 
1146 	/*
1147 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1148 	 */
1149 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1150 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1151 			cmd->data_direction, sam_task_attr,
1152 			cmd->sense_buffer + 2);
1153 
1154 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1155 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1156 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1157 		conn->cid);
1158 
1159 	target_get_sess_cmd(&cmd->se_cmd, true);
1160 
1161 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
1162 						     scsilun_to_int(&hdr->lun));
1163 	if (cmd->sense_reason)
1164 		goto attach_cmd;
1165 
1166 	/* only used for printks or comparing with ->ref_task_tag */
1167 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1168 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
1169 	if (cmd->sense_reason) {
1170 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1171 			return iscsit_add_reject_cmd(cmd,
1172 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1173 		}
1174 
1175 		goto attach_cmd;
1176 	}
1177 
1178 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1179 		return iscsit_add_reject_cmd(cmd,
1180 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1181 	}
1182 
1183 attach_cmd:
1184 	spin_lock_bh(&conn->cmd_lock);
1185 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1186 	spin_unlock_bh(&conn->cmd_lock);
1187 	/*
1188 	 * Check if we need to delay processing because of ALUA
1189 	 * Active/NonOptimized primary access state..
1190 	 */
1191 	core_alua_check_nonop_delay(&cmd->se_cmd);
1192 
1193 	return 0;
1194 }
1195 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1196 
1197 void iscsit_set_unsolicited_dataout(struct iscsi_cmd *cmd)
1198 {
1199 	iscsit_set_dataout_sequence_values(cmd);
1200 
1201 	spin_lock_bh(&cmd->dataout_timeout_lock);
1202 	iscsit_start_dataout_timer(cmd, cmd->conn);
1203 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1204 }
1205 EXPORT_SYMBOL(iscsit_set_unsolicited_dataout);
1206 
1207 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1208 			    struct iscsi_scsi_req *hdr)
1209 {
1210 	int cmdsn_ret = 0;
1211 	/*
1212 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1213 	 * the Immediate Bit is not set, and no Immediate
1214 	 * Data is attached.
1215 	 *
1216 	 * A PDU/CmdSN carrying Immediate Data can only
1217 	 * be processed after the DataCRC has passed.
1218 	 * If the DataCRC fails, the CmdSN MUST NOT
1219 	 * be acknowledged. (See below)
1220 	 */
1221 	if (!cmd->immediate_data) {
1222 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1223 					(unsigned char *)hdr, hdr->cmdsn);
1224 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1225 			return -1;
1226 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1227 			target_put_sess_cmd(&cmd->se_cmd);
1228 			return 0;
1229 		}
1230 	}
1231 
1232 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1233 
1234 	/*
1235 	 * If no Immediate Data is attached, it's OK to return now.
1236 	 */
1237 	if (!cmd->immediate_data) {
1238 		if (!cmd->sense_reason && cmd->unsolicited_data)
1239 			iscsit_set_unsolicited_dataout(cmd);
1240 		if (!cmd->sense_reason)
1241 			return 0;
1242 
1243 		target_put_sess_cmd(&cmd->se_cmd);
1244 		return 0;
1245 	}
1246 
1247 	/*
1248 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1249 	 * execution.  These exceptions are processed in CmdSN order using
1250 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1251 	 */
1252 	if (cmd->sense_reason)
1253 		return 1;
1254 	/*
1255 	 * Call directly into transport_generic_new_cmd() to perform
1256 	 * the backend memory allocation.
1257 	 */
1258 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1259 	if (cmd->sense_reason)
1260 		return 1;
1261 
1262 	return 0;
1263 }
1264 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1265 
1266 static int
1267 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1268 			  bool dump_payload)
1269 {
1270 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1271 	/*
1272 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1273 	 */
1274 	if (dump_payload)
1275 		goto after_immediate_data;
1276 	/*
1277 	 * Check for underflow case where both EDTL and immediate data payload
1278 	 * exceeds what is presented by CDB's TRANSFER LENGTH, and what has
1279 	 * already been set in target_cmd_size_check() as se_cmd->data_length.
1280 	 *
1281 	 * For this special case, fail the command and dump the immediate data
1282 	 * payload.
1283 	 */
1284 	if (cmd->first_burst_len > cmd->se_cmd.data_length) {
1285 		cmd->sense_reason = TCM_INVALID_CDB_FIELD;
1286 		goto after_immediate_data;
1287 	}
1288 
1289 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1290 					cmd->first_burst_len);
1291 after_immediate_data:
1292 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1293 		/*
1294 		 * A PDU/CmdSN carrying Immediate Data passed
1295 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1296 		 * Immediate Bit is not set.
1297 		 */
1298 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1299 					(unsigned char *)hdr, hdr->cmdsn);
1300 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1301 			return -1;
1302 
1303 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1304 			int rc;
1305 
1306 			rc = iscsit_dump_data_payload(cmd->conn,
1307 						      cmd->first_burst_len, 1);
1308 			target_put_sess_cmd(&cmd->se_cmd);
1309 			return rc;
1310 		} else if (cmd->unsolicited_data)
1311 			iscsit_set_unsolicited_dataout(cmd);
1312 
1313 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1314 		/*
1315 		 * Immediate Data failed DataCRC and ERL>=1,
1316 		 * silently drop this PDU and let the initiator
1317 		 * plug the CmdSN gap.
1318 		 *
1319 		 * FIXME: Send Unsolicited NOPIN with reserved
1320 		 * TTT here to help the initiator figure out
1321 		 * the missing CmdSN, although they should be
1322 		 * intelligent enough to determine the missing
1323 		 * CmdSN and issue a retry to plug the sequence.
1324 		 */
1325 		cmd->i_state = ISTATE_REMOVE;
1326 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1327 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1328 		return -1;
1329 
1330 	return 0;
1331 }
1332 
1333 static int
1334 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1335 			   unsigned char *buf)
1336 {
1337 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1338 	int rc, immed_data;
1339 	bool dump_payload = false;
1340 
1341 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1342 	if (rc < 0)
1343 		return 0;
1344 	/*
1345 	 * Allocation iovecs needed for struct socket operations for
1346 	 * traditional iSCSI block I/O.
1347 	 */
1348 	if (iscsit_allocate_iovecs(cmd) < 0) {
1349 		return iscsit_reject_cmd(cmd,
1350 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1351 	}
1352 	immed_data = cmd->immediate_data;
1353 
1354 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1355 	if (rc < 0)
1356 		return rc;
1357 	else if (rc > 0)
1358 		dump_payload = true;
1359 
1360 	if (!immed_data)
1361 		return 0;
1362 
1363 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1364 }
1365 
1366 static u32 iscsit_do_crypto_hash_sg(
1367 	struct ahash_request *hash,
1368 	struct iscsi_cmd *cmd,
1369 	u32 data_offset,
1370 	u32 data_length,
1371 	u32 padding,
1372 	u8 *pad_bytes)
1373 {
1374 	u32 data_crc;
1375 	struct scatterlist *sg;
1376 	unsigned int page_off;
1377 
1378 	crypto_ahash_init(hash);
1379 
1380 	sg = cmd->first_data_sg;
1381 	page_off = cmd->first_data_sg_off;
1382 
1383 	while (data_length) {
1384 		u32 cur_len = min_t(u32, data_length, (sg->length - page_off));
1385 
1386 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1387 		crypto_ahash_update(hash);
1388 
1389 		data_length -= cur_len;
1390 		page_off = 0;
1391 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1392 		sg = sg_next(sg);
1393 	}
1394 
1395 	if (padding) {
1396 		struct scatterlist pad_sg;
1397 
1398 		sg_init_one(&pad_sg, pad_bytes, padding);
1399 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1400 					padding);
1401 		crypto_ahash_finup(hash);
1402 	} else {
1403 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1404 		crypto_ahash_final(hash);
1405 	}
1406 
1407 	return data_crc;
1408 }
1409 
1410 static void iscsit_do_crypto_hash_buf(struct ahash_request *hash,
1411 	const void *buf, u32 payload_length, u32 padding,
1412 	const void *pad_bytes, void *data_crc)
1413 {
1414 	struct scatterlist sg[2];
1415 
1416 	sg_init_table(sg, ARRAY_SIZE(sg));
1417 	sg_set_buf(sg, buf, payload_length);
1418 	if (padding)
1419 		sg_set_buf(sg + 1, pad_bytes, padding);
1420 
1421 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1422 
1423 	crypto_ahash_digest(hash);
1424 }
1425 
1426 int
1427 __iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1428 			   struct iscsi_cmd *cmd, u32 payload_length,
1429 			   bool *success)
1430 {
1431 	struct iscsi_data *hdr = buf;
1432 	struct se_cmd *se_cmd;
1433 	int rc;
1434 
1435 	/* iSCSI write */
1436 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1437 
1438 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1439 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1440 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1441 		payload_length, conn->cid);
1442 
1443 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1444 		pr_err("Command ITT: 0x%08x received DataOUT after"
1445 			" last DataOUT received, dumping payload\n",
1446 			cmd->init_task_tag);
1447 		return iscsit_dump_data_payload(conn, payload_length, 1);
1448 	}
1449 
1450 	if (cmd->data_direction != DMA_TO_DEVICE) {
1451 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1452 			" NON-WRITE command.\n", cmd->init_task_tag);
1453 		return iscsit_dump_data_payload(conn, payload_length, 1);
1454 	}
1455 	se_cmd = &cmd->se_cmd;
1456 	iscsit_mod_dataout_timer(cmd);
1457 
1458 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1459 		pr_err("DataOut Offset: %u, Length %u greater than iSCSI Command EDTL %u, protocol error.\n",
1460 		       be32_to_cpu(hdr->offset), payload_length,
1461 		       cmd->se_cmd.data_length);
1462 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1463 	}
1464 
1465 	if (cmd->unsolicited_data) {
1466 		int dump_unsolicited_data = 0;
1467 
1468 		if (conn->sess->sess_ops->InitialR2T) {
1469 			pr_err("Received unexpected unsolicited data"
1470 				" while InitialR2T=Yes, protocol error.\n");
1471 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1472 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1473 			return -1;
1474 		}
1475 		/*
1476 		 * Special case for dealing with Unsolicited DataOUT
1477 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1478 		 * failures;
1479 		 */
1480 
1481 		/* Something's amiss if we're not in WRITE_PENDING state... */
1482 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1483 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1484 			dump_unsolicited_data = 1;
1485 
1486 		if (dump_unsolicited_data) {
1487 			/*
1488 			 * Check if a delayed TASK_ABORTED status needs to
1489 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1490 			 * received with the unsolicited data out.
1491 			 */
1492 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1493 				iscsit_stop_dataout_timer(cmd);
1494 
1495 			return iscsit_dump_data_payload(conn, payload_length, 1);
1496 		}
1497 	} else {
1498 		/*
1499 		 * For the normal solicited data path:
1500 		 *
1501 		 * Check for a delayed TASK_ABORTED status and dump any
1502 		 * incoming data out payload if one exists.  Also, when the
1503 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1504 		 * data out sequence, we decrement outstanding_r2ts.  Once
1505 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1506 		 * TASK_ABORTED status.
1507 		 */
1508 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1509 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL &&
1510 			    --cmd->outstanding_r2ts < 1)
1511 				iscsit_stop_dataout_timer(cmd);
1512 
1513 			return iscsit_dump_data_payload(conn, payload_length, 1);
1514 		}
1515 	}
1516 	/*
1517 	 * Perform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1518 	 * within-command recovery checks before receiving the payload.
1519 	 */
1520 	rc = iscsit_check_pre_dataout(cmd, buf);
1521 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1522 		return 0;
1523 	else if (rc == DATAOUT_CANNOT_RECOVER)
1524 		return -1;
1525 	*success = true;
1526 	return 0;
1527 }
1528 EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
1529 
1530 int
1531 iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1532 			 struct iscsi_cmd **out_cmd)
1533 {
1534 	struct iscsi_data *hdr = buf;
1535 	struct iscsi_cmd *cmd;
1536 	u32 payload_length = ntoh24(hdr->dlength);
1537 	int rc;
1538 	bool success = false;
1539 
1540 	if (!payload_length) {
1541 		pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
1542 		return 0;
1543 	}
1544 
1545 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1546 		pr_err_ratelimited("DataSegmentLength: %u is greater than"
1547 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1548 			conn->conn_ops->MaxXmitDataSegmentLength);
1549 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
1550 	}
1551 
1552 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
1553 	if (!cmd)
1554 		return 0;
1555 
1556 	rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
1557 
1558 	if (success)
1559 		*out_cmd = cmd;
1560 
1561 	return rc;
1562 }
1563 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1564 
1565 static int
1566 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1567 		   struct iscsi_data *hdr)
1568 {
1569 	struct kvec *iov;
1570 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1571 	u32 payload_length = ntoh24(hdr->dlength);
1572 	int iov_ret, data_crc_failed = 0;
1573 
1574 	rx_size += payload_length;
1575 	iov = &cmd->iov_data[0];
1576 
1577 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1578 				   payload_length);
1579 	if (iov_ret < 0)
1580 		return -1;
1581 
1582 	iov_count += iov_ret;
1583 
1584 	padding = ((-payload_length) & 3);
1585 	if (padding != 0) {
1586 		iov[iov_count].iov_base	= cmd->pad_bytes;
1587 		iov[iov_count++].iov_len = padding;
1588 		rx_size += padding;
1589 		pr_debug("Receiving %u padding bytes.\n", padding);
1590 	}
1591 
1592 	if (conn->conn_ops->DataDigest) {
1593 		iov[iov_count].iov_base = &checksum;
1594 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1595 		rx_size += ISCSI_CRC_LEN;
1596 	}
1597 
1598 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1599 
1600 	iscsit_unmap_iovec(cmd);
1601 
1602 	if (rx_got != rx_size)
1603 		return -1;
1604 
1605 	if (conn->conn_ops->DataDigest) {
1606 		u32 data_crc;
1607 
1608 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1609 						    be32_to_cpu(hdr->offset),
1610 						    payload_length, padding,
1611 						    cmd->pad_bytes);
1612 
1613 		if (checksum != data_crc) {
1614 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1615 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1616 				" does not match computed 0x%08x\n",
1617 				hdr->itt, hdr->offset, payload_length,
1618 				hdr->datasn, checksum, data_crc);
1619 			data_crc_failed = 1;
1620 		} else {
1621 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1622 				" %u bytes of Data Out\n", checksum,
1623 				payload_length);
1624 		}
1625 	}
1626 
1627 	return data_crc_failed;
1628 }
1629 
1630 int
1631 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1632 			     bool data_crc_failed)
1633 {
1634 	struct iscsi_conn *conn = cmd->conn;
1635 	int rc, ooo_cmdsn;
1636 	/*
1637 	 * Increment post receive data and CRC values or perform
1638 	 * within-command recovery.
1639 	 */
1640 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1641 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1642 		return 0;
1643 	else if (rc == DATAOUT_SEND_R2T) {
1644 		iscsit_set_dataout_sequence_values(cmd);
1645 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1646 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1647 		/*
1648 		 * Handle extra special case for out of order
1649 		 * Unsolicited Data Out.
1650 		 */
1651 		spin_lock_bh(&cmd->istate_lock);
1652 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1653 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1654 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1655 		spin_unlock_bh(&cmd->istate_lock);
1656 
1657 		iscsit_stop_dataout_timer(cmd);
1658 		if (ooo_cmdsn)
1659 			return 0;
1660 		target_execute_cmd(&cmd->se_cmd);
1661 		return 0;
1662 	} else /* DATAOUT_CANNOT_RECOVER */
1663 		return -1;
1664 
1665 	return 0;
1666 }
1667 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1668 
1669 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1670 {
1671 	struct iscsi_cmd *cmd = NULL;
1672 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1673 	int rc;
1674 	bool data_crc_failed = false;
1675 
1676 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1677 	if (rc < 0)
1678 		return 0;
1679 	else if (!cmd)
1680 		return 0;
1681 
1682 	rc = iscsit_get_dataout(conn, cmd, hdr);
1683 	if (rc < 0)
1684 		return rc;
1685 	else if (rc > 0)
1686 		data_crc_failed = true;
1687 
1688 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1689 }
1690 
1691 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1692 			 struct iscsi_nopout *hdr)
1693 {
1694 	u32 payload_length = ntoh24(hdr->dlength);
1695 
1696 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1697 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1698 		if (!cmd)
1699 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1700 						 (unsigned char *)hdr);
1701 
1702 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1703 					 (unsigned char *)hdr);
1704 	}
1705 
1706 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1707 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1708 			" not set, protocol error.\n");
1709 		if (!cmd)
1710 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1711 						 (unsigned char *)hdr);
1712 
1713 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1714 					 (unsigned char *)hdr);
1715 	}
1716 
1717 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1718 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1719 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1720 			" error.\n", payload_length,
1721 			conn->conn_ops->MaxXmitDataSegmentLength);
1722 		if (!cmd)
1723 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1724 						 (unsigned char *)hdr);
1725 
1726 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1727 					 (unsigned char *)hdr);
1728 	}
1729 
1730 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1731 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1732 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1733 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1734 		payload_length);
1735 	/*
1736 	 * This is not a response to a Unsolicited NopIN, which means
1737 	 * it can either be a NOPOUT ping request (with a valid ITT),
1738 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1739 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1740 	 * can contain ping data.
1741 	 */
1742 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1743 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1744 		cmd->i_state		= ISTATE_SEND_NOPIN;
1745 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1746 						1 : 0);
1747 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1748 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1749 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1750 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1751 		cmd->data_direction	= DMA_NONE;
1752 	}
1753 
1754 	return 0;
1755 }
1756 EXPORT_SYMBOL(iscsit_setup_nop_out);
1757 
1758 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1759 			   struct iscsi_nopout *hdr)
1760 {
1761 	struct iscsi_cmd *cmd_p = NULL;
1762 	int cmdsn_ret = 0;
1763 	/*
1764 	 * Initiator is expecting a NopIN ping reply..
1765 	 */
1766 	if (hdr->itt != RESERVED_ITT) {
1767 		if (!cmd)
1768 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1769 						(unsigned char *)hdr);
1770 
1771 		spin_lock_bh(&conn->cmd_lock);
1772 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1773 		spin_unlock_bh(&conn->cmd_lock);
1774 
1775 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1776 
1777 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1778 			iscsit_add_cmd_to_response_queue(cmd, conn,
1779 							 cmd->i_state);
1780 			return 0;
1781 		}
1782 
1783 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1784 				(unsigned char *)hdr, hdr->cmdsn);
1785                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1786 			return 0;
1787 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1788 			return -1;
1789 
1790 		return 0;
1791 	}
1792 	/*
1793 	 * This was a response to a unsolicited NOPIN ping.
1794 	 */
1795 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1796 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1797 		if (!cmd_p)
1798 			return -EINVAL;
1799 
1800 		iscsit_stop_nopin_response_timer(conn);
1801 
1802 		cmd_p->i_state = ISTATE_REMOVE;
1803 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1804 
1805 		iscsit_start_nopin_timer(conn);
1806 		return 0;
1807 	}
1808 	/*
1809 	 * Otherwise, initiator is not expecting a NOPIN is response.
1810 	 * Just ignore for now.
1811 	 */
1812 
1813 	if (cmd)
1814 		iscsit_free_cmd(cmd, false);
1815 
1816         return 0;
1817 }
1818 EXPORT_SYMBOL(iscsit_process_nop_out);
1819 
1820 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1821 				 unsigned char *buf)
1822 {
1823 	unsigned char *ping_data = NULL;
1824 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1825 	struct kvec *iov = NULL;
1826 	u32 payload_length = ntoh24(hdr->dlength);
1827 	int ret;
1828 
1829 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1830 	if (ret < 0)
1831 		return 0;
1832 	/*
1833 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1834 	 */
1835 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1836 		u32 checksum, data_crc, padding = 0;
1837 		int niov = 0, rx_got, rx_size = payload_length;
1838 
1839 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1840 		if (!ping_data) {
1841 			ret = -1;
1842 			goto out;
1843 		}
1844 
1845 		iov = &cmd->iov_misc[0];
1846 		iov[niov].iov_base	= ping_data;
1847 		iov[niov++].iov_len	= payload_length;
1848 
1849 		padding = ((-payload_length) & 3);
1850 		if (padding != 0) {
1851 			pr_debug("Receiving %u additional bytes"
1852 				" for padding.\n", padding);
1853 			iov[niov].iov_base	= &cmd->pad_bytes;
1854 			iov[niov++].iov_len	= padding;
1855 			rx_size += padding;
1856 		}
1857 		if (conn->conn_ops->DataDigest) {
1858 			iov[niov].iov_base	= &checksum;
1859 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1860 			rx_size += ISCSI_CRC_LEN;
1861 		}
1862 
1863 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1864 		if (rx_got != rx_size) {
1865 			ret = -1;
1866 			goto out;
1867 		}
1868 
1869 		if (conn->conn_ops->DataDigest) {
1870 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, ping_data,
1871 						  payload_length, padding,
1872 						  cmd->pad_bytes, &data_crc);
1873 
1874 			if (checksum != data_crc) {
1875 				pr_err("Ping data CRC32C DataDigest"
1876 				" 0x%08x does not match computed 0x%08x\n",
1877 					checksum, data_crc);
1878 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1879 					pr_err("Unable to recover from"
1880 					" NOPOUT Ping DataCRC failure while in"
1881 						" ERL=0.\n");
1882 					ret = -1;
1883 					goto out;
1884 				} else {
1885 					/*
1886 					 * Silently drop this PDU and let the
1887 					 * initiator plug the CmdSN gap.
1888 					 */
1889 					pr_debug("Dropping NOPOUT"
1890 					" Command CmdSN: 0x%08x due to"
1891 					" DataCRC error.\n", hdr->cmdsn);
1892 					ret = 0;
1893 					goto out;
1894 				}
1895 			} else {
1896 				pr_debug("Got CRC32C DataDigest"
1897 				" 0x%08x for %u bytes of ping data.\n",
1898 					checksum, payload_length);
1899 			}
1900 		}
1901 
1902 		ping_data[payload_length] = '\0';
1903 		/*
1904 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1905 		 */
1906 		cmd->buf_ptr = ping_data;
1907 		cmd->buf_ptr_size = payload_length;
1908 
1909 		pr_debug("Got %u bytes of NOPOUT ping"
1910 			" data.\n", payload_length);
1911 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1912 	}
1913 
1914 	return iscsit_process_nop_out(conn, cmd, hdr);
1915 out:
1916 	if (cmd)
1917 		iscsit_free_cmd(cmd, false);
1918 
1919 	kfree(ping_data);
1920 	return ret;
1921 }
1922 
1923 static enum tcm_tmreq_table iscsit_convert_tmf(u8 iscsi_tmf)
1924 {
1925 	switch (iscsi_tmf) {
1926 	case ISCSI_TM_FUNC_ABORT_TASK:
1927 		return TMR_ABORT_TASK;
1928 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1929 		return TMR_ABORT_TASK_SET;
1930 	case ISCSI_TM_FUNC_CLEAR_ACA:
1931 		return TMR_CLEAR_ACA;
1932 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1933 		return TMR_CLEAR_TASK_SET;
1934 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1935 		return TMR_LUN_RESET;
1936 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1937 		return TMR_TARGET_WARM_RESET;
1938 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1939 		return TMR_TARGET_COLD_RESET;
1940 	default:
1941 		return TMR_UNKNOWN;
1942 	}
1943 }
1944 
1945 int
1946 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1947 			   unsigned char *buf)
1948 {
1949 	struct se_tmr_req *se_tmr;
1950 	struct iscsi_tmr_req *tmr_req;
1951 	struct iscsi_tm *hdr;
1952 	int out_of_order_cmdsn = 0, ret;
1953 	u8 function, tcm_function = TMR_UNKNOWN;
1954 
1955 	hdr			= (struct iscsi_tm *) buf;
1956 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1957 	function = hdr->flags;
1958 
1959 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1960 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1961 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1962 		hdr->rtt, hdr->refcmdsn, conn->cid);
1963 
1964 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1965 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1966 	     hdr->rtt != RESERVED_ITT)) {
1967 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1968 		hdr->rtt = RESERVED_ITT;
1969 	}
1970 
1971 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1972 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1973 		pr_err("Task Management Request TASK_REASSIGN not"
1974 			" issued as immediate command, bad iSCSI Initiator"
1975 				"implementation\n");
1976 		return iscsit_add_reject_cmd(cmd,
1977 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1978 	}
1979 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1980 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1981 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1982 
1983 	cmd->data_direction = DMA_NONE;
1984 	cmd->tmr_req = kzalloc(sizeof(*cmd->tmr_req), GFP_KERNEL);
1985 	if (!cmd->tmr_req) {
1986 		return iscsit_add_reject_cmd(cmd,
1987 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1988 					     buf);
1989 	}
1990 
1991 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1992 			      conn->sess->se_sess, 0, DMA_NONE,
1993 			      TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
1994 
1995 	target_get_sess_cmd(&cmd->se_cmd, true);
1996 
1997 	/*
1998 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1999 	 * LIO-Target $FABRIC_MOD
2000 	 */
2001 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2002 		tcm_function = iscsit_convert_tmf(function);
2003 		if (tcm_function == TMR_UNKNOWN) {
2004 			pr_err("Unknown iSCSI TMR Function:"
2005 			       " 0x%02x\n", function);
2006 			return iscsit_add_reject_cmd(cmd,
2007 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2008 		}
2009 	}
2010 	ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
2011 				 GFP_KERNEL);
2012 	if (ret < 0)
2013 		return iscsit_add_reject_cmd(cmd,
2014 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2015 
2016 	cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2017 
2018 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2019 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2020 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2021 	cmd->init_task_tag	= hdr->itt;
2022 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2023 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2024 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2025 	se_tmr			= cmd->se_cmd.se_tmr_req;
2026 	tmr_req			= cmd->tmr_req;
2027 	/*
2028 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2029 	 */
2030 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2031 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
2032 					       scsilun_to_int(&hdr->lun));
2033 		if (ret < 0) {
2034 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2035 			goto attach;
2036 		}
2037 	}
2038 
2039 	switch (function) {
2040 	case ISCSI_TM_FUNC_ABORT_TASK:
2041 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2042 		if (se_tmr->response)
2043 			goto attach;
2044 		break;
2045 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2046 	case ISCSI_TM_FUNC_CLEAR_ACA:
2047 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2048 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2049 		break;
2050 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2051 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2052 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2053 			goto attach;
2054 		}
2055 		break;
2056 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2057 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2058 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2059 			goto attach;
2060 		}
2061 		break;
2062 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2063 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2064 		/*
2065 		 * Perform sanity checks on the ExpDataSN only if the
2066 		 * TASK_REASSIGN was successful.
2067 		 */
2068 		if (se_tmr->response)
2069 			break;
2070 
2071 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2072 			return iscsit_add_reject_cmd(cmd,
2073 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2074 		break;
2075 	default:
2076 		pr_err("Unknown TMR function: 0x%02x, protocol"
2077 			" error.\n", function);
2078 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2079 		goto attach;
2080 	}
2081 
2082 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2083 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2084 		se_tmr->call_transport = 1;
2085 attach:
2086 	spin_lock_bh(&conn->cmd_lock);
2087 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2088 	spin_unlock_bh(&conn->cmd_lock);
2089 
2090 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2091 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2092 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP) {
2093 			out_of_order_cmdsn = 1;
2094 		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2095 			target_put_sess_cmd(&cmd->se_cmd);
2096 			return 0;
2097 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2098 			return -1;
2099 		}
2100 	}
2101 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2102 
2103 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2104 		return 0;
2105 	/*
2106 	 * Found the referenced task, send to transport for processing.
2107 	 */
2108 	if (se_tmr->call_transport)
2109 		return transport_generic_handle_tmr(&cmd->se_cmd);
2110 
2111 	/*
2112 	 * Could not find the referenced LUN, task, or Task Management
2113 	 * command not authorized or supported.  Change state and
2114 	 * let the tx_thread send the response.
2115 	 *
2116 	 * For connection recovery, this is also the default action for
2117 	 * TMR TASK_REASSIGN.
2118 	 */
2119 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2120 	target_put_sess_cmd(&cmd->se_cmd);
2121 	return 0;
2122 }
2123 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2124 
2125 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2126 int
2127 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2128 		      struct iscsi_text *hdr)
2129 {
2130 	u32 payload_length = ntoh24(hdr->dlength);
2131 
2132 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2133 		pr_err("Unable to accept text parameter length: %u"
2134 			"greater than MaxXmitDataSegmentLength %u.\n",
2135 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2136 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2137 					 (unsigned char *)hdr);
2138 	}
2139 
2140 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2141 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2142 		pr_err("Multi sequence text commands currently not supported\n");
2143 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2144 					(unsigned char *)hdr);
2145 	}
2146 
2147 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2148 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2149 		hdr->exp_statsn, payload_length);
2150 
2151 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2152 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2153 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2154 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2155 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2156 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2157 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2158 	cmd->data_direction	= DMA_NONE;
2159 	kfree(cmd->text_in_ptr);
2160 	cmd->text_in_ptr	= NULL;
2161 
2162 	return 0;
2163 }
2164 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2165 
2166 int
2167 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2168 			struct iscsi_text *hdr)
2169 {
2170 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2171 	int cmdsn_ret;
2172 
2173 	if (!text_in) {
2174 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2175 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2176 			pr_err("Unable to locate text_in buffer for sendtargets"
2177 			       " discovery\n");
2178 			goto reject;
2179 		}
2180 		goto empty_sendtargets;
2181 	}
2182 	if (strncmp("SendTargets", text_in, 11) != 0) {
2183 		pr_err("Received Text Data that is not"
2184 			" SendTargets, cannot continue.\n");
2185 		goto reject;
2186 	}
2187 	text_ptr = strchr(text_in, '=');
2188 	if (!text_ptr) {
2189 		pr_err("No \"=\" separator found in Text Data,"
2190 			"  cannot continue.\n");
2191 		goto reject;
2192 	}
2193 	if (!strncmp("=All", text_ptr, 4)) {
2194 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2195 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2196 		   !strncmp("=eui.", text_ptr, 5)) {
2197 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2198 	} else {
2199 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2200 		goto reject;
2201 	}
2202 
2203 	spin_lock_bh(&conn->cmd_lock);
2204 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2205 	spin_unlock_bh(&conn->cmd_lock);
2206 
2207 empty_sendtargets:
2208 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2209 
2210 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2211 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2212 				(unsigned char *)hdr, hdr->cmdsn);
2213 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2214 			return -1;
2215 
2216 		return 0;
2217 	}
2218 
2219 	return iscsit_execute_cmd(cmd, 0);
2220 
2221 reject:
2222 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2223 				 (unsigned char *)hdr);
2224 }
2225 EXPORT_SYMBOL(iscsit_process_text_cmd);
2226 
2227 static int
2228 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2229 		       unsigned char *buf)
2230 {
2231 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2232 	char *text_in = NULL;
2233 	u32 payload_length = ntoh24(hdr->dlength);
2234 	int rx_size, rc;
2235 
2236 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2237 	if (rc < 0)
2238 		return 0;
2239 
2240 	rx_size = payload_length;
2241 	if (payload_length) {
2242 		u32 checksum = 0, data_crc = 0;
2243 		u32 padding = 0;
2244 		int niov = 0, rx_got;
2245 		struct kvec iov[2];
2246 
2247 		rx_size = ALIGN(payload_length, 4);
2248 		text_in = kzalloc(rx_size, GFP_KERNEL);
2249 		if (!text_in)
2250 			goto reject;
2251 
2252 		cmd->text_in_ptr = text_in;
2253 
2254 		memset(iov, 0, sizeof(iov));
2255 		iov[niov].iov_base	= text_in;
2256 		iov[niov++].iov_len	= rx_size;
2257 
2258 		padding = rx_size - payload_length;
2259 		if (padding)
2260 			pr_debug("Receiving %u additional bytes"
2261 					" for padding.\n", padding);
2262 		if (conn->conn_ops->DataDigest) {
2263 			iov[niov].iov_base	= &checksum;
2264 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2265 			rx_size += ISCSI_CRC_LEN;
2266 		}
2267 
2268 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2269 		if (rx_got != rx_size)
2270 			goto reject;
2271 
2272 		if (conn->conn_ops->DataDigest) {
2273 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2274 						  text_in, rx_size, 0, NULL,
2275 						  &data_crc);
2276 
2277 			if (checksum != data_crc) {
2278 				pr_err("Text data CRC32C DataDigest"
2279 					" 0x%08x does not match computed"
2280 					" 0x%08x\n", checksum, data_crc);
2281 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2282 					pr_err("Unable to recover from"
2283 					" Text Data digest failure while in"
2284 						" ERL=0.\n");
2285 					goto reject;
2286 				} else {
2287 					/*
2288 					 * Silently drop this PDU and let the
2289 					 * initiator plug the CmdSN gap.
2290 					 */
2291 					pr_debug("Dropping Text"
2292 					" Command CmdSN: 0x%08x due to"
2293 					" DataCRC error.\n", hdr->cmdsn);
2294 					kfree(text_in);
2295 					return 0;
2296 				}
2297 			} else {
2298 				pr_debug("Got CRC32C DataDigest"
2299 					" 0x%08x for %u bytes of text data.\n",
2300 						checksum, payload_length);
2301 			}
2302 		}
2303 		text_in[payload_length - 1] = '\0';
2304 		pr_debug("Successfully read %d bytes of text"
2305 				" data.\n", payload_length);
2306 	}
2307 
2308 	return iscsit_process_text_cmd(conn, cmd, hdr);
2309 
2310 reject:
2311 	kfree(cmd->text_in_ptr);
2312 	cmd->text_in_ptr = NULL;
2313 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2314 }
2315 
2316 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2317 {
2318 	struct iscsi_conn *conn_p;
2319 	struct iscsi_session *sess = conn->sess;
2320 
2321 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2322 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2323 
2324 	atomic_set(&sess->session_logout, 1);
2325 	atomic_set(&conn->conn_logout_remove, 1);
2326 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2327 
2328 	iscsit_inc_conn_usage_count(conn);
2329 	iscsit_inc_session_usage_count(sess);
2330 
2331 	spin_lock_bh(&sess->conn_lock);
2332 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2333 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2334 			continue;
2335 
2336 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2337 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2338 	}
2339 	spin_unlock_bh(&sess->conn_lock);
2340 
2341 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2342 
2343 	return 0;
2344 }
2345 
2346 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2347 {
2348 	struct iscsi_conn *l_conn;
2349 	struct iscsi_session *sess = conn->sess;
2350 
2351 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2352 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2353 
2354 	/*
2355 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2356 	 * can arrive on a connection with a differing CID.
2357 	 */
2358 	if (conn->cid == cmd->logout_cid) {
2359 		spin_lock_bh(&conn->state_lock);
2360 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2361 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2362 
2363 		atomic_set(&conn->conn_logout_remove, 1);
2364 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2365 		iscsit_inc_conn_usage_count(conn);
2366 
2367 		spin_unlock_bh(&conn->state_lock);
2368 	} else {
2369 		/*
2370 		 * Handle all different cid CLOSECONNECTION requests in
2371 		 * iscsit_logout_post_handler_diffcid() as to give enough
2372 		 * time for any non immediate command's CmdSN to be
2373 		 * acknowledged on the connection in question.
2374 		 *
2375 		 * Here we simply make sure the CID is still around.
2376 		 */
2377 		l_conn = iscsit_get_conn_from_cid(sess,
2378 				cmd->logout_cid);
2379 		if (!l_conn) {
2380 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2381 			iscsit_add_cmd_to_response_queue(cmd, conn,
2382 					cmd->i_state);
2383 			return 0;
2384 		}
2385 
2386 		iscsit_dec_conn_usage_count(l_conn);
2387 	}
2388 
2389 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2390 
2391 	return 0;
2392 }
2393 
2394 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2395 {
2396 	struct iscsi_session *sess = conn->sess;
2397 
2398 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2399 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2400 
2401 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2402 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2403 			" while ERL!=2.\n");
2404 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2405 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2406 		return 0;
2407 	}
2408 
2409 	if (conn->cid == cmd->logout_cid) {
2410 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2411 			" with CID: %hu on CID: %hu, implementation error.\n",
2412 				cmd->logout_cid, conn->cid);
2413 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2414 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2415 		return 0;
2416 	}
2417 
2418 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2419 
2420 	return 0;
2421 }
2422 
2423 int
2424 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2425 			unsigned char *buf)
2426 {
2427 	int cmdsn_ret, logout_remove = 0;
2428 	u8 reason_code = 0;
2429 	struct iscsi_logout *hdr;
2430 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2431 
2432 	hdr			= (struct iscsi_logout *) buf;
2433 	reason_code		= (hdr->flags & 0x7f);
2434 
2435 	if (tiqn) {
2436 		spin_lock(&tiqn->logout_stats.lock);
2437 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2438 			tiqn->logout_stats.normal_logouts++;
2439 		else
2440 			tiqn->logout_stats.abnormal_logouts++;
2441 		spin_unlock(&tiqn->logout_stats.lock);
2442 	}
2443 
2444 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2445 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2446 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2447 		hdr->cid, conn->cid);
2448 
2449 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2450 		pr_err("Received logout request on connection that"
2451 			" is not in logged in state, ignoring request.\n");
2452 		iscsit_free_cmd(cmd, false);
2453 		return 0;
2454 	}
2455 
2456 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2457 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2458 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2459 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2460 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2461 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2462 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2463 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2464 	cmd->logout_reason      = reason_code;
2465 	cmd->data_direction     = DMA_NONE;
2466 
2467 	/*
2468 	 * We need to sleep in these cases (by returning 1) until the Logout
2469 	 * Response gets sent in the tx thread.
2470 	 */
2471 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2472 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2473 	    be16_to_cpu(hdr->cid) == conn->cid))
2474 		logout_remove = 1;
2475 
2476 	spin_lock_bh(&conn->cmd_lock);
2477 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2478 	spin_unlock_bh(&conn->cmd_lock);
2479 
2480 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2481 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2482 
2483 	/*
2484 	 * Immediate commands are executed, well, immediately.
2485 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2486 	 */
2487 	if (cmd->immediate_cmd) {
2488 		int ret = iscsit_execute_cmd(cmd, 0);
2489 
2490 		if (ret < 0)
2491 			return ret;
2492 	} else {
2493 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2494 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2495 			logout_remove = 0;
2496 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2497 			return -1;
2498 	}
2499 
2500 	return logout_remove;
2501 }
2502 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2503 
2504 int iscsit_handle_snack(
2505 	struct iscsi_conn *conn,
2506 	unsigned char *buf)
2507 {
2508 	struct iscsi_snack *hdr;
2509 
2510 	hdr			= (struct iscsi_snack *) buf;
2511 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2512 
2513 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2514 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2515 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2516 			hdr->begrun, hdr->runlength, conn->cid);
2517 
2518 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2519 		pr_err("Initiator sent SNACK request while in"
2520 			" ErrorRecoveryLevel=0.\n");
2521 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2522 					 buf);
2523 	}
2524 	/*
2525 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2526 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2527 	 */
2528 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2529 	case 0:
2530 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2531 			hdr->itt,
2532 			be32_to_cpu(hdr->ttt),
2533 			be32_to_cpu(hdr->begrun),
2534 			be32_to_cpu(hdr->runlength));
2535 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2536 		return iscsit_handle_status_snack(conn, hdr->itt,
2537 			be32_to_cpu(hdr->ttt),
2538 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2539 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2540 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2541 			be32_to_cpu(hdr->begrun),
2542 			be32_to_cpu(hdr->runlength));
2543 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2544 		/* FIXME: Support R-Data SNACK */
2545 		pr_err("R-Data SNACK Not Supported.\n");
2546 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2547 					 buf);
2548 	default:
2549 		pr_err("Unknown SNACK type 0x%02x, protocol"
2550 			" error.\n", hdr->flags & 0x0f);
2551 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2552 					 buf);
2553 	}
2554 
2555 	return 0;
2556 }
2557 EXPORT_SYMBOL(iscsit_handle_snack);
2558 
2559 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2560 {
2561 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2562 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2563 		wait_for_completion_interruptible_timeout(
2564 					&conn->rx_half_close_comp,
2565 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2566 	}
2567 }
2568 
2569 static int iscsit_handle_immediate_data(
2570 	struct iscsi_cmd *cmd,
2571 	struct iscsi_scsi_req *hdr,
2572 	u32 length)
2573 {
2574 	int iov_ret, rx_got = 0, rx_size = 0;
2575 	u32 checksum, iov_count = 0, padding = 0;
2576 	struct iscsi_conn *conn = cmd->conn;
2577 	struct kvec *iov;
2578 
2579 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2580 	if (iov_ret < 0)
2581 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2582 
2583 	rx_size = length;
2584 	iov_count = iov_ret;
2585 	iov = &cmd->iov_data[0];
2586 
2587 	padding = ((-length) & 3);
2588 	if (padding != 0) {
2589 		iov[iov_count].iov_base	= cmd->pad_bytes;
2590 		iov[iov_count++].iov_len = padding;
2591 		rx_size += padding;
2592 	}
2593 
2594 	if (conn->conn_ops->DataDigest) {
2595 		iov[iov_count].iov_base		= &checksum;
2596 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2597 		rx_size += ISCSI_CRC_LEN;
2598 	}
2599 
2600 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2601 
2602 	iscsit_unmap_iovec(cmd);
2603 
2604 	if (rx_got != rx_size) {
2605 		iscsit_rx_thread_wait_for_tcp(conn);
2606 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2607 	}
2608 
2609 	if (conn->conn_ops->DataDigest) {
2610 		u32 data_crc;
2611 
2612 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2613 						    cmd->write_data_done, length, padding,
2614 						    cmd->pad_bytes);
2615 
2616 		if (checksum != data_crc) {
2617 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2618 				" does not match computed 0x%08x\n", checksum,
2619 				data_crc);
2620 
2621 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2622 				pr_err("Unable to recover from"
2623 					" Immediate Data digest failure while"
2624 					" in ERL=0.\n");
2625 				iscsit_reject_cmd(cmd,
2626 						ISCSI_REASON_DATA_DIGEST_ERROR,
2627 						(unsigned char *)hdr);
2628 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2629 			} else {
2630 				iscsit_reject_cmd(cmd,
2631 						ISCSI_REASON_DATA_DIGEST_ERROR,
2632 						(unsigned char *)hdr);
2633 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2634 			}
2635 		} else {
2636 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2637 				" %u bytes of Immediate Data\n", checksum,
2638 				length);
2639 		}
2640 	}
2641 
2642 	cmd->write_data_done += length;
2643 
2644 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2645 		spin_lock_bh(&cmd->istate_lock);
2646 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2647 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2648 		spin_unlock_bh(&cmd->istate_lock);
2649 	}
2650 
2651 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2652 }
2653 
2654 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2655 	with active network interface */
2656 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2657 {
2658 	struct iscsi_cmd *cmd;
2659 	struct iscsi_conn *conn_p;
2660 	bool found = false;
2661 
2662 	lockdep_assert_held(&conn->sess->conn_lock);
2663 
2664 	/*
2665 	 * Only send a Asynchronous Message on connections whos network
2666 	 * interface is still functional.
2667 	 */
2668 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2669 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2670 			iscsit_inc_conn_usage_count(conn_p);
2671 			found = true;
2672 			break;
2673 		}
2674 	}
2675 
2676 	if (!found)
2677 		return;
2678 
2679 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2680 	if (!cmd) {
2681 		iscsit_dec_conn_usage_count(conn_p);
2682 		return;
2683 	}
2684 
2685 	cmd->logout_cid = conn->cid;
2686 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2687 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2688 
2689 	spin_lock_bh(&conn_p->cmd_lock);
2690 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2691 	spin_unlock_bh(&conn_p->cmd_lock);
2692 
2693 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2694 	iscsit_dec_conn_usage_count(conn_p);
2695 }
2696 
2697 static int iscsit_send_conn_drop_async_message(
2698 	struct iscsi_cmd *cmd,
2699 	struct iscsi_conn *conn)
2700 {
2701 	struct iscsi_async *hdr;
2702 
2703 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2704 
2705 	hdr			= (struct iscsi_async *) cmd->pdu;
2706 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2707 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2708 	cmd->init_task_tag	= RESERVED_ITT;
2709 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2710 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2711 	cmd->stat_sn		= conn->stat_sn++;
2712 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2713 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2714 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2715 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2716 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2717 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2718 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2719 
2720 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2721 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2722 			cmd->logout_cid, conn->cid);
2723 
2724 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2725 }
2726 
2727 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2728 {
2729 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2730 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2731 		wait_for_completion_interruptible_timeout(
2732 					&conn->tx_half_close_comp,
2733 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2734 	}
2735 }
2736 
2737 void
2738 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2739 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2740 			bool set_statsn)
2741 {
2742 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2743 	hdr->flags		= datain->flags;
2744 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2745 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2746 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2747 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2748 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2749 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2750 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2751 		}
2752 	}
2753 	hton24(hdr->dlength, datain->length);
2754 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2755 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2756 				(struct scsi_lun *)&hdr->lun);
2757 	else
2758 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2759 
2760 	hdr->itt		= cmd->init_task_tag;
2761 
2762 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2763 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2764 	else
2765 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2766 	if (set_statsn)
2767 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2768 	else
2769 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2770 
2771 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2772 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2773 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2774 	hdr->offset		= cpu_to_be32(datain->offset);
2775 
2776 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2777 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2778 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2779 		ntohl(hdr->offset), datain->length, conn->cid);
2780 }
2781 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2782 
2783 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2784 {
2785 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2786 	struct iscsi_datain datain;
2787 	struct iscsi_datain_req *dr;
2788 	int eodr = 0, ret;
2789 	bool set_statsn = false;
2790 
2791 	memset(&datain, 0, sizeof(struct iscsi_datain));
2792 	dr = iscsit_get_datain_values(cmd, &datain);
2793 	if (!dr) {
2794 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2795 				cmd->init_task_tag);
2796 		return -1;
2797 	}
2798 	/*
2799 	 * Be paranoid and double check the logic for now.
2800 	 */
2801 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2802 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2803 			" datain.length: %u exceeds cmd->data_length: %u\n",
2804 			cmd->init_task_tag, datain.offset, datain.length,
2805 			cmd->se_cmd.data_length);
2806 		return -1;
2807 	}
2808 
2809 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2810 	/*
2811 	 * Special case for successfully execution w/ both DATAIN
2812 	 * and Sense Data.
2813 	 */
2814 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2815 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2816 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2817 	else {
2818 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2819 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2820 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2821 			cmd->stat_sn = conn->stat_sn++;
2822 			set_statsn = true;
2823 		} else if (dr->dr_complete ==
2824 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2825 			set_statsn = true;
2826 	}
2827 
2828 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2829 
2830 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2831 	if (ret < 0)
2832 		return ret;
2833 
2834 	if (dr->dr_complete) {
2835 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2836 				2 : 1;
2837 		iscsit_free_datain_req(cmd, dr);
2838 	}
2839 
2840 	return eodr;
2841 }
2842 
2843 int
2844 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2845 			struct iscsi_logout_rsp *hdr)
2846 {
2847 	struct iscsi_conn *logout_conn = NULL;
2848 	struct iscsi_conn_recovery *cr = NULL;
2849 	struct iscsi_session *sess = conn->sess;
2850 	/*
2851 	 * The actual shutting down of Sessions and/or Connections
2852 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2853 	 * is done in scsi_logout_post_handler().
2854 	 */
2855 	switch (cmd->logout_reason) {
2856 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2857 		pr_debug("iSCSI session logout successful, setting"
2858 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2859 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2860 		break;
2861 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2862 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2863 			break;
2864 		/*
2865 		 * For CLOSECONNECTION logout requests carrying
2866 		 * a matching logout CID -> local CID, the reference
2867 		 * for the local CID will have been incremented in
2868 		 * iscsi_logout_closeconnection().
2869 		 *
2870 		 * For CLOSECONNECTION logout requests carrying
2871 		 * a different CID than the connection it arrived
2872 		 * on, the connection responding to cmd->logout_cid
2873 		 * is stopped in iscsit_logout_post_handler_diffcid().
2874 		 */
2875 
2876 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2877 			" successful.\n", cmd->logout_cid, conn->cid);
2878 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2879 		break;
2880 	case ISCSI_LOGOUT_REASON_RECOVERY:
2881 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2882 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2883 			break;
2884 		/*
2885 		 * If the connection is still active from our point of view
2886 		 * force connection recovery to occur.
2887 		 */
2888 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2889 				cmd->logout_cid);
2890 		if (logout_conn) {
2891 			iscsit_connection_reinstatement_rcfr(logout_conn);
2892 			iscsit_dec_conn_usage_count(logout_conn);
2893 		}
2894 
2895 		cr = iscsit_get_inactive_connection_recovery_entry(
2896 				conn->sess, cmd->logout_cid);
2897 		if (!cr) {
2898 			pr_err("Unable to locate CID: %hu for"
2899 			" REMOVECONNFORRECOVERY Logout Request.\n",
2900 				cmd->logout_cid);
2901 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2902 			break;
2903 		}
2904 
2905 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2906 
2907 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2908 			" for recovery for CID: %hu on CID: %hu successful.\n",
2909 				cmd->logout_cid, conn->cid);
2910 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2911 		break;
2912 	default:
2913 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2914 				cmd->logout_reason);
2915 		return -1;
2916 	}
2917 
2918 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2919 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2920 	hdr->response		= cmd->logout_response;
2921 	hdr->itt		= cmd->init_task_tag;
2922 	cmd->stat_sn		= conn->stat_sn++;
2923 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2924 
2925 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2926 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2927 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2928 
2929 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2930 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2931 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2932 		cmd->logout_cid, conn->cid);
2933 
2934 	return 0;
2935 }
2936 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2937 
2938 static int
2939 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2940 {
2941 	int rc;
2942 
2943 	rc = iscsit_build_logout_rsp(cmd, conn,
2944 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2945 	if (rc < 0)
2946 		return rc;
2947 
2948 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2949 }
2950 
2951 void
2952 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2953 		       struct iscsi_nopin *hdr, bool nopout_response)
2954 {
2955 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2956 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2957         hton24(hdr->dlength, cmd->buf_ptr_size);
2958 	if (nopout_response)
2959 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2960 	hdr->itt		= cmd->init_task_tag;
2961 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2962 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2963 				  conn->stat_sn;
2964 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2965 
2966 	if (nopout_response)
2967 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2968 
2969 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2970 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2971 
2972 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2973 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2974 		"Solicited" : "Unsolicited", cmd->init_task_tag,
2975 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2976 }
2977 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2978 
2979 /*
2980  *	Unsolicited NOPIN, either requesting a response or not.
2981  */
2982 static int iscsit_send_unsolicited_nopin(
2983 	struct iscsi_cmd *cmd,
2984 	struct iscsi_conn *conn,
2985 	int want_response)
2986 {
2987 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
2988 	int ret;
2989 
2990 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
2991 
2992 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
2993 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
2994 
2995 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2996 	if (ret < 0)
2997 		return ret;
2998 
2999 	spin_lock_bh(&cmd->istate_lock);
3000 	cmd->i_state = want_response ?
3001 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3002 	spin_unlock_bh(&cmd->istate_lock);
3003 
3004 	return 0;
3005 }
3006 
3007 static int
3008 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3009 {
3010 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3011 
3012 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3013 
3014 	/*
3015 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
3016 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
3017 	 */
3018 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3019 
3020 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3021 						     cmd->buf_ptr,
3022 						     cmd->buf_ptr_size);
3023 }
3024 
3025 static int iscsit_send_r2t(
3026 	struct iscsi_cmd *cmd,
3027 	struct iscsi_conn *conn)
3028 {
3029 	struct iscsi_r2t *r2t;
3030 	struct iscsi_r2t_rsp *hdr;
3031 	int ret;
3032 
3033 	r2t = iscsit_get_r2t_from_list(cmd);
3034 	if (!r2t)
3035 		return -1;
3036 
3037 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3038 	memset(hdr, 0, ISCSI_HDR_LEN);
3039 	hdr->opcode		= ISCSI_OP_R2T;
3040 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3041 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3042 			(struct scsi_lun *)&hdr->lun);
3043 	hdr->itt		= cmd->init_task_tag;
3044 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3045 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3046 	else
3047 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3048 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3049 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3050 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3051 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3052 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3053 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3054 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3055 
3056 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3057 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3058 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3059 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3060 			r2t->offset, r2t->xfer_len, conn->cid);
3061 
3062 	spin_lock_bh(&cmd->r2t_lock);
3063 	r2t->sent_r2t = 1;
3064 	spin_unlock_bh(&cmd->r2t_lock);
3065 
3066 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3067 	if (ret < 0) {
3068 		return ret;
3069 	}
3070 
3071 	spin_lock_bh(&cmd->dataout_timeout_lock);
3072 	iscsit_start_dataout_timer(cmd, conn);
3073 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3074 
3075 	return 0;
3076 }
3077 
3078 /*
3079  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3080  *		connection recovery.
3081  */
3082 int iscsit_build_r2ts_for_cmd(
3083 	struct iscsi_conn *conn,
3084 	struct iscsi_cmd *cmd,
3085 	bool recovery)
3086 {
3087 	int first_r2t = 1;
3088 	u32 offset = 0, xfer_len = 0;
3089 
3090 	spin_lock_bh(&cmd->r2t_lock);
3091 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3092 		spin_unlock_bh(&cmd->r2t_lock);
3093 		return 0;
3094 	}
3095 
3096 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3097 	    !recovery)
3098 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3099 
3100 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3101 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3102 			offset = cmd->r2t_offset;
3103 
3104 			if (first_r2t && recovery) {
3105 				int new_data_end = offset +
3106 					conn->sess->sess_ops->MaxBurstLength -
3107 					cmd->next_burst_len;
3108 
3109 				if (new_data_end > cmd->se_cmd.data_length)
3110 					xfer_len = cmd->se_cmd.data_length - offset;
3111 				else
3112 					xfer_len =
3113 						conn->sess->sess_ops->MaxBurstLength -
3114 						cmd->next_burst_len;
3115 			} else {
3116 				int new_data_end = offset +
3117 					conn->sess->sess_ops->MaxBurstLength;
3118 
3119 				if (new_data_end > cmd->se_cmd.data_length)
3120 					xfer_len = cmd->se_cmd.data_length - offset;
3121 				else
3122 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3123 			}
3124 			cmd->r2t_offset += xfer_len;
3125 
3126 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3127 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3128 		} else {
3129 			struct iscsi_seq *seq;
3130 
3131 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3132 			if (!seq) {
3133 				spin_unlock_bh(&cmd->r2t_lock);
3134 				return -1;
3135 			}
3136 
3137 			offset = seq->offset;
3138 			xfer_len = seq->xfer_len;
3139 
3140 			if (cmd->seq_send_order == cmd->seq_count)
3141 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3142 		}
3143 		cmd->outstanding_r2ts++;
3144 		first_r2t = 0;
3145 
3146 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3147 			spin_unlock_bh(&cmd->r2t_lock);
3148 			return -1;
3149 		}
3150 
3151 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3152 			break;
3153 	}
3154 	spin_unlock_bh(&cmd->r2t_lock);
3155 
3156 	return 0;
3157 }
3158 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3159 
3160 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3161 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3162 {
3163 	if (inc_stat_sn)
3164 		cmd->stat_sn = conn->stat_sn++;
3165 
3166 	atomic_long_inc(&conn->sess->rsp_pdus);
3167 
3168 	memset(hdr, 0, ISCSI_HDR_LEN);
3169 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3170 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3171 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3172 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3173 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3174 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3175 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3176 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3177 	}
3178 	hdr->response		= cmd->iscsi_response;
3179 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3180 	hdr->itt		= cmd->init_task_tag;
3181 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3182 
3183 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3184 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3185 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3186 
3187 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3188 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3189 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3190 		cmd->se_cmd.scsi_status, conn->cid);
3191 }
3192 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3193 
3194 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3195 {
3196 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3197 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3198 	void *data_buf = NULL;
3199 	u32 padding = 0, data_buf_len = 0;
3200 
3201 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3202 
3203 	/*
3204 	 * Attach SENSE DATA payload to iSCSI Response PDU
3205 	 */
3206 	if (cmd->se_cmd.sense_buffer &&
3207 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3208 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3209 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3210 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3211 
3212 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3213 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3214 		data_buf = cmd->sense_buffer;
3215 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3216 
3217 		if (padding) {
3218 			memset(cmd->sense_buffer +
3219 				cmd->se_cmd.scsi_sense_length, 0, padding);
3220 			pr_debug("Adding %u bytes of padding to"
3221 				" SENSE.\n", padding);
3222 		}
3223 
3224 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3225 				" Response PDU\n",
3226 				cmd->se_cmd.scsi_sense_length);
3227 	}
3228 
3229 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3230 						     data_buf_len);
3231 }
3232 
3233 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3234 {
3235 	switch (se_tmr->response) {
3236 	case TMR_FUNCTION_COMPLETE:
3237 		return ISCSI_TMF_RSP_COMPLETE;
3238 	case TMR_TASK_DOES_NOT_EXIST:
3239 		return ISCSI_TMF_RSP_NO_TASK;
3240 	case TMR_LUN_DOES_NOT_EXIST:
3241 		return ISCSI_TMF_RSP_NO_LUN;
3242 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3243 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3244 	case TMR_FUNCTION_REJECTED:
3245 	default:
3246 		return ISCSI_TMF_RSP_REJECTED;
3247 	}
3248 }
3249 
3250 void
3251 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3252 			  struct iscsi_tm_rsp *hdr)
3253 {
3254 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3255 
3256 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3257 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3258 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3259 	hdr->itt		= cmd->init_task_tag;
3260 	cmd->stat_sn		= conn->stat_sn++;
3261 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3262 
3263 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3264 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3265 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3266 
3267 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3268 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3269 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3270 }
3271 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3272 
3273 static int
3274 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3275 {
3276 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3277 
3278 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3279 
3280 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3281 }
3282 
3283 #define SENDTARGETS_BUF_LIMIT 32768U
3284 
3285 static int
3286 iscsit_build_sendtargets_response(struct iscsi_cmd *cmd,
3287 				  enum iscsit_transport_type network_transport,
3288 				  int skip_bytes, bool *completed)
3289 {
3290 	char *payload = NULL;
3291 	struct iscsi_conn *conn = cmd->conn;
3292 	struct iscsi_portal_group *tpg;
3293 	struct iscsi_tiqn *tiqn;
3294 	struct iscsi_tpg_np *tpg_np;
3295 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3296 	int target_name_printed;
3297 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3298 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3299 	bool active;
3300 
3301 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3302 			 SENDTARGETS_BUF_LIMIT);
3303 
3304 	payload = kzalloc(buffer_len, GFP_KERNEL);
3305 	if (!payload)
3306 		return -ENOMEM;
3307 
3308 	/*
3309 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3310 	 * explicit case..
3311 	 */
3312 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3313 		text_ptr = strchr(text_in, '=');
3314 		if (!text_ptr) {
3315 			pr_err("Unable to locate '=' string in text_in:"
3316 			       " %s\n", text_in);
3317 			kfree(payload);
3318 			return -EINVAL;
3319 		}
3320 		/*
3321 		 * Skip over '=' character..
3322 		 */
3323 		text_ptr += 1;
3324 	}
3325 
3326 	spin_lock(&tiqn_lock);
3327 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3328 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3329 		     strcmp(tiqn->tiqn, text_ptr)) {
3330 			continue;
3331 		}
3332 
3333 		target_name_printed = 0;
3334 
3335 		spin_lock(&tiqn->tiqn_tpg_lock);
3336 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3337 
3338 			/* If demo_mode_discovery=0 and generate_node_acls=0
3339 			 * (demo mode dislabed) do not return
3340 			 * TargetName+TargetAddress unless a NodeACL exists.
3341 			 */
3342 
3343 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3344 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3345 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3346 				cmd->conn->sess->sess_ops->InitiatorName))) {
3347 				continue;
3348 			}
3349 
3350 			spin_lock(&tpg->tpg_state_lock);
3351 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3352 			spin_unlock(&tpg->tpg_state_lock);
3353 
3354 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3355 				continue;
3356 
3357 			spin_lock(&tpg->tpg_np_lock);
3358 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3359 						tpg_np_list) {
3360 				struct iscsi_np *np = tpg_np->tpg_np;
3361 				struct sockaddr_storage *sockaddr;
3362 
3363 				if (np->np_network_transport != network_transport)
3364 					continue;
3365 
3366 				if (!target_name_printed) {
3367 					len = sprintf(buf, "TargetName=%s",
3368 						      tiqn->tiqn);
3369 					len += 1;
3370 
3371 					if ((len + payload_len) > buffer_len) {
3372 						spin_unlock(&tpg->tpg_np_lock);
3373 						spin_unlock(&tiqn->tiqn_tpg_lock);
3374 						end_of_buf = 1;
3375 						goto eob;
3376 					}
3377 
3378 					if (skip_bytes && len <= skip_bytes) {
3379 						skip_bytes -= len;
3380 					} else {
3381 						memcpy(payload + payload_len, buf, len);
3382 						payload_len += len;
3383 						target_name_printed = 1;
3384 						if (len > skip_bytes)
3385 							skip_bytes = 0;
3386 					}
3387 				}
3388 
3389 				if (inet_addr_is_any((struct sockaddr *)&np->np_sockaddr))
3390 					sockaddr = &conn->local_sockaddr;
3391 				else
3392 					sockaddr = &np->np_sockaddr;
3393 
3394 				len = sprintf(buf, "TargetAddress="
3395 					      "%pISpc,%hu",
3396 					      sockaddr,
3397 					      tpg->tpgt);
3398 				len += 1;
3399 
3400 				if ((len + payload_len) > buffer_len) {
3401 					spin_unlock(&tpg->tpg_np_lock);
3402 					spin_unlock(&tiqn->tiqn_tpg_lock);
3403 					end_of_buf = 1;
3404 					goto eob;
3405 				}
3406 
3407 				if (skip_bytes && len <= skip_bytes) {
3408 					skip_bytes -= len;
3409 				} else {
3410 					memcpy(payload + payload_len, buf, len);
3411 					payload_len += len;
3412 					if (len > skip_bytes)
3413 						skip_bytes = 0;
3414 				}
3415 			}
3416 			spin_unlock(&tpg->tpg_np_lock);
3417 		}
3418 		spin_unlock(&tiqn->tiqn_tpg_lock);
3419 eob:
3420 		if (end_of_buf) {
3421 			*completed = false;
3422 			break;
3423 		}
3424 
3425 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3426 			break;
3427 	}
3428 	spin_unlock(&tiqn_lock);
3429 
3430 	cmd->buf_ptr = payload;
3431 
3432 	return payload_len;
3433 }
3434 
3435 int
3436 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3437 		      struct iscsi_text_rsp *hdr,
3438 		      enum iscsit_transport_type network_transport)
3439 {
3440 	int text_length, padding;
3441 	bool completed = true;
3442 
3443 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3444 							cmd->read_data_done,
3445 							&completed);
3446 	if (text_length < 0)
3447 		return text_length;
3448 
3449 	if (completed) {
3450 		hdr->flags = ISCSI_FLAG_CMD_FINAL;
3451 	} else {
3452 		hdr->flags = ISCSI_FLAG_TEXT_CONTINUE;
3453 		cmd->read_data_done += text_length;
3454 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3455 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3456 	}
3457 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3458 	padding = ((-text_length) & 3);
3459 	hton24(hdr->dlength, text_length);
3460 	hdr->itt = cmd->init_task_tag;
3461 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3462 	cmd->stat_sn = conn->stat_sn++;
3463 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3464 
3465 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3466 	/*
3467 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3468 	 * correctly increment MaxCmdSN for each response answering a
3469 	 * non immediate text request with a valid CmdSN.
3470 	 */
3471 	cmd->maxcmdsn_inc = 0;
3472 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3473 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3474 
3475 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3476 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3477 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3478 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3479 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3480 
3481 	return text_length + padding;
3482 }
3483 EXPORT_SYMBOL(iscsit_build_text_rsp);
3484 
3485 static int iscsit_send_text_rsp(
3486 	struct iscsi_cmd *cmd,
3487 	struct iscsi_conn *conn)
3488 {
3489 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3490 	int text_length;
3491 
3492 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3493 				conn->conn_transport->transport_type);
3494 	if (text_length < 0)
3495 		return text_length;
3496 
3497 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3498 						     cmd->buf_ptr,
3499 						     text_length);
3500 }
3501 
3502 void
3503 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3504 		    struct iscsi_reject *hdr)
3505 {
3506 	hdr->opcode		= ISCSI_OP_REJECT;
3507 	hdr->reason		= cmd->reject_reason;
3508 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3509 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3510 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3511 	cmd->stat_sn		= conn->stat_sn++;
3512 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3513 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3514 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3515 
3516 }
3517 EXPORT_SYMBOL(iscsit_build_reject);
3518 
3519 static int iscsit_send_reject(
3520 	struct iscsi_cmd *cmd,
3521 	struct iscsi_conn *conn)
3522 {
3523 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3524 
3525 	iscsit_build_reject(cmd, conn, hdr);
3526 
3527 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3528 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3529 
3530 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3531 						     cmd->buf_ptr,
3532 						     ISCSI_HDR_LEN);
3533 }
3534 
3535 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3536 {
3537 	int ord, cpu;
3538 	/*
3539 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3540 	 * within iscsit_start_kthreads()
3541 	 *
3542 	 * Here we use bitmap_id to determine which CPU that this
3543 	 * iSCSI connection's RX/TX threads will be scheduled to
3544 	 * execute upon.
3545 	 */
3546 	ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3547 	for_each_online_cpu(cpu) {
3548 		if (ord-- == 0) {
3549 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3550 			return;
3551 		}
3552 	}
3553 	/*
3554 	 * This should never be reached..
3555 	 */
3556 	dump_stack();
3557 	cpumask_setall(conn->conn_cpumask);
3558 }
3559 
3560 int
3561 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3562 {
3563 	int ret;
3564 
3565 	switch (state) {
3566 	case ISTATE_SEND_R2T:
3567 		ret = iscsit_send_r2t(cmd, conn);
3568 		if (ret < 0)
3569 			goto err;
3570 		break;
3571 	case ISTATE_REMOVE:
3572 		spin_lock_bh(&conn->cmd_lock);
3573 		list_del_init(&cmd->i_conn_node);
3574 		spin_unlock_bh(&conn->cmd_lock);
3575 
3576 		iscsit_free_cmd(cmd, false);
3577 		break;
3578 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3579 		iscsit_mod_nopin_response_timer(conn);
3580 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3581 		if (ret < 0)
3582 			goto err;
3583 		break;
3584 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3585 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3586 		if (ret < 0)
3587 			goto err;
3588 		break;
3589 	default:
3590 		pr_err("Unknown Opcode: 0x%02x ITT:"
3591 		       " 0x%08x, i_state: %d on CID: %hu\n",
3592 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3593 		       conn->cid);
3594 		goto err;
3595 	}
3596 
3597 	return 0;
3598 
3599 err:
3600 	return -1;
3601 }
3602 EXPORT_SYMBOL(iscsit_immediate_queue);
3603 
3604 static int
3605 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3606 {
3607 	struct iscsit_transport *t = conn->conn_transport;
3608 	struct iscsi_queue_req *qr;
3609 	struct iscsi_cmd *cmd;
3610 	u8 state;
3611 	int ret;
3612 
3613 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3614 		atomic_set(&conn->check_immediate_queue, 0);
3615 		cmd = qr->cmd;
3616 		state = qr->state;
3617 		kmem_cache_free(lio_qr_cache, qr);
3618 
3619 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3620 		if (ret < 0)
3621 			return ret;
3622 	}
3623 
3624 	return 0;
3625 }
3626 
3627 int
3628 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3629 {
3630 	int ret;
3631 
3632 check_rsp_state:
3633 	switch (state) {
3634 	case ISTATE_SEND_DATAIN:
3635 		ret = iscsit_send_datain(cmd, conn);
3636 		if (ret < 0)
3637 			goto err;
3638 		else if (!ret)
3639 			/* more drs */
3640 			goto check_rsp_state;
3641 		else if (ret == 1) {
3642 			/* all done */
3643 			spin_lock_bh(&cmd->istate_lock);
3644 			cmd->i_state = ISTATE_SENT_STATUS;
3645 			spin_unlock_bh(&cmd->istate_lock);
3646 
3647 			if (atomic_read(&conn->check_immediate_queue))
3648 				return 1;
3649 
3650 			return 0;
3651 		} else if (ret == 2) {
3652 			/* Still must send status,
3653 			   SCF_TRANSPORT_TASK_SENSE was set */
3654 			spin_lock_bh(&cmd->istate_lock);
3655 			cmd->i_state = ISTATE_SEND_STATUS;
3656 			spin_unlock_bh(&cmd->istate_lock);
3657 			state = ISTATE_SEND_STATUS;
3658 			goto check_rsp_state;
3659 		}
3660 
3661 		break;
3662 	case ISTATE_SEND_STATUS:
3663 	case ISTATE_SEND_STATUS_RECOVERY:
3664 		ret = iscsit_send_response(cmd, conn);
3665 		break;
3666 	case ISTATE_SEND_LOGOUTRSP:
3667 		ret = iscsit_send_logout(cmd, conn);
3668 		break;
3669 	case ISTATE_SEND_ASYNCMSG:
3670 		ret = iscsit_send_conn_drop_async_message(
3671 			cmd, conn);
3672 		break;
3673 	case ISTATE_SEND_NOPIN:
3674 		ret = iscsit_send_nopin(cmd, conn);
3675 		break;
3676 	case ISTATE_SEND_REJECT:
3677 		ret = iscsit_send_reject(cmd, conn);
3678 		break;
3679 	case ISTATE_SEND_TASKMGTRSP:
3680 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3681 		if (ret != 0)
3682 			break;
3683 		ret = iscsit_tmr_post_handler(cmd, conn);
3684 		if (ret != 0)
3685 			iscsit_fall_back_to_erl0(conn->sess);
3686 		break;
3687 	case ISTATE_SEND_TEXTRSP:
3688 		ret = iscsit_send_text_rsp(cmd, conn);
3689 		break;
3690 	default:
3691 		pr_err("Unknown Opcode: 0x%02x ITT:"
3692 		       " 0x%08x, i_state: %d on CID: %hu\n",
3693 		       cmd->iscsi_opcode, cmd->init_task_tag,
3694 		       state, conn->cid);
3695 		goto err;
3696 	}
3697 	if (ret < 0)
3698 		goto err;
3699 
3700 	switch (state) {
3701 	case ISTATE_SEND_LOGOUTRSP:
3702 		if (!iscsit_logout_post_handler(cmd, conn))
3703 			return -ECONNRESET;
3704 		/* fall through */
3705 	case ISTATE_SEND_STATUS:
3706 	case ISTATE_SEND_ASYNCMSG:
3707 	case ISTATE_SEND_NOPIN:
3708 	case ISTATE_SEND_STATUS_RECOVERY:
3709 	case ISTATE_SEND_TEXTRSP:
3710 	case ISTATE_SEND_TASKMGTRSP:
3711 	case ISTATE_SEND_REJECT:
3712 		spin_lock_bh(&cmd->istate_lock);
3713 		cmd->i_state = ISTATE_SENT_STATUS;
3714 		spin_unlock_bh(&cmd->istate_lock);
3715 		break;
3716 	default:
3717 		pr_err("Unknown Opcode: 0x%02x ITT:"
3718 		       " 0x%08x, i_state: %d on CID: %hu\n",
3719 		       cmd->iscsi_opcode, cmd->init_task_tag,
3720 		       cmd->i_state, conn->cid);
3721 		goto err;
3722 	}
3723 
3724 	if (atomic_read(&conn->check_immediate_queue))
3725 		return 1;
3726 
3727 	return 0;
3728 
3729 err:
3730 	return -1;
3731 }
3732 EXPORT_SYMBOL(iscsit_response_queue);
3733 
3734 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3735 {
3736 	struct iscsit_transport *t = conn->conn_transport;
3737 	struct iscsi_queue_req *qr;
3738 	struct iscsi_cmd *cmd;
3739 	u8 state;
3740 	int ret;
3741 
3742 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3743 		cmd = qr->cmd;
3744 		state = qr->state;
3745 		kmem_cache_free(lio_qr_cache, qr);
3746 
3747 		ret = t->iscsit_response_queue(conn, cmd, state);
3748 		if (ret == 1 || ret < 0)
3749 			return ret;
3750 	}
3751 
3752 	return 0;
3753 }
3754 
3755 int iscsi_target_tx_thread(void *arg)
3756 {
3757 	int ret = 0;
3758 	struct iscsi_conn *conn = arg;
3759 	bool conn_freed = false;
3760 
3761 	/*
3762 	 * Allow ourselves to be interrupted by SIGINT so that a
3763 	 * connection recovery / failure event can be triggered externally.
3764 	 */
3765 	allow_signal(SIGINT);
3766 
3767 	while (!kthread_should_stop()) {
3768 		/*
3769 		 * Ensure that both TX and RX per connection kthreads
3770 		 * are scheduled to run on the same CPU.
3771 		 */
3772 		iscsit_thread_check_cpumask(conn, current, 1);
3773 
3774 		wait_event_interruptible(conn->queues_wq,
3775 					 !iscsit_conn_all_queues_empty(conn));
3776 
3777 		if (signal_pending(current))
3778 			goto transport_err;
3779 
3780 get_immediate:
3781 		ret = iscsit_handle_immediate_queue(conn);
3782 		if (ret < 0)
3783 			goto transport_err;
3784 
3785 		ret = iscsit_handle_response_queue(conn);
3786 		if (ret == 1) {
3787 			goto get_immediate;
3788 		} else if (ret == -ECONNRESET) {
3789 			conn_freed = true;
3790 			goto out;
3791 		} else if (ret < 0) {
3792 			goto transport_err;
3793 		}
3794 	}
3795 
3796 transport_err:
3797 	/*
3798 	 * Avoid the normal connection failure code-path if this connection
3799 	 * is still within LOGIN mode, and iscsi_np process context is
3800 	 * responsible for cleaning up the early connection failure.
3801 	 */
3802 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3803 		iscsit_take_action_for_connection_exit(conn, &conn_freed);
3804 out:
3805 	if (!conn_freed) {
3806 		while (!kthread_should_stop()) {
3807 			msleep(100);
3808 		}
3809 	}
3810 	return 0;
3811 }
3812 
3813 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3814 {
3815 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3816 	struct iscsi_cmd *cmd;
3817 	int ret = 0;
3818 
3819 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3820 	case ISCSI_OP_SCSI_CMD:
3821 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3822 		if (!cmd)
3823 			goto reject;
3824 
3825 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3826 		break;
3827 	case ISCSI_OP_SCSI_DATA_OUT:
3828 		ret = iscsit_handle_data_out(conn, buf);
3829 		break;
3830 	case ISCSI_OP_NOOP_OUT:
3831 		cmd = NULL;
3832 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3833 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3834 			if (!cmd)
3835 				goto reject;
3836 		}
3837 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3838 		break;
3839 	case ISCSI_OP_SCSI_TMFUNC:
3840 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3841 		if (!cmd)
3842 			goto reject;
3843 
3844 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3845 		break;
3846 	case ISCSI_OP_TEXT:
3847 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3848 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3849 			if (!cmd)
3850 				goto reject;
3851 		} else {
3852 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3853 			if (!cmd)
3854 				goto reject;
3855 		}
3856 
3857 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3858 		break;
3859 	case ISCSI_OP_LOGOUT:
3860 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3861 		if (!cmd)
3862 			goto reject;
3863 
3864 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3865 		if (ret > 0)
3866 			wait_for_completion_timeout(&conn->conn_logout_comp,
3867 					SECONDS_FOR_LOGOUT_COMP * HZ);
3868 		break;
3869 	case ISCSI_OP_SNACK:
3870 		ret = iscsit_handle_snack(conn, buf);
3871 		break;
3872 	default:
3873 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3874 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3875 			pr_err("Cannot recover from unknown"
3876 			" opcode while ERL=0, closing iSCSI connection.\n");
3877 			return -1;
3878 		}
3879 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
3880 		       " closing iSCSI connection.\n");
3881 		ret = -1;
3882 		break;
3883 	}
3884 
3885 	return ret;
3886 reject:
3887 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
3888 }
3889 
3890 static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
3891 {
3892 	bool ret;
3893 
3894 	spin_lock_bh(&conn->state_lock);
3895 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
3896 	spin_unlock_bh(&conn->state_lock);
3897 
3898 	return ret;
3899 }
3900 
3901 static void iscsit_get_rx_pdu(struct iscsi_conn *conn)
3902 {
3903 	int ret;
3904 	u8 *buffer, opcode;
3905 	u32 checksum = 0, digest = 0;
3906 	struct kvec iov;
3907 
3908 	buffer = kcalloc(ISCSI_HDR_LEN, sizeof(*buffer), GFP_KERNEL);
3909 	if (!buffer)
3910 		return;
3911 
3912 	while (!kthread_should_stop()) {
3913 		/*
3914 		 * Ensure that both TX and RX per connection kthreads
3915 		 * are scheduled to run on the same CPU.
3916 		 */
3917 		iscsit_thread_check_cpumask(conn, current, 0);
3918 
3919 		memset(&iov, 0, sizeof(struct kvec));
3920 
3921 		iov.iov_base	= buffer;
3922 		iov.iov_len	= ISCSI_HDR_LEN;
3923 
3924 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
3925 		if (ret != ISCSI_HDR_LEN) {
3926 			iscsit_rx_thread_wait_for_tcp(conn);
3927 			break;
3928 		}
3929 
3930 		if (conn->conn_ops->HeaderDigest) {
3931 			iov.iov_base	= &digest;
3932 			iov.iov_len	= ISCSI_CRC_LEN;
3933 
3934 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
3935 			if (ret != ISCSI_CRC_LEN) {
3936 				iscsit_rx_thread_wait_for_tcp(conn);
3937 				break;
3938 			}
3939 
3940 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, buffer,
3941 						  ISCSI_HDR_LEN, 0, NULL,
3942 						  &checksum);
3943 
3944 			if (digest != checksum) {
3945 				pr_err("HeaderDigest CRC32C failed,"
3946 					" received 0x%08x, computed 0x%08x\n",
3947 					digest, checksum);
3948 				/*
3949 				 * Set the PDU to 0xff so it will intentionally
3950 				 * hit default in the switch below.
3951 				 */
3952 				memset(buffer, 0xff, ISCSI_HDR_LEN);
3953 				atomic_long_inc(&conn->sess->conn_digest_errors);
3954 			} else {
3955 				pr_debug("Got HeaderDigest CRC32C"
3956 						" 0x%08x\n", checksum);
3957 			}
3958 		}
3959 
3960 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
3961 			break;
3962 
3963 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
3964 
3965 		if (conn->sess->sess_ops->SessionType &&
3966 		   ((!(opcode & ISCSI_OP_TEXT)) ||
3967 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
3968 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
3969 			" while in Discovery Session, rejecting.\n", opcode);
3970 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
3971 					  buffer);
3972 			break;
3973 		}
3974 
3975 		ret = iscsi_target_rx_opcode(conn, buffer);
3976 		if (ret < 0)
3977 			break;
3978 	}
3979 
3980 	kfree(buffer);
3981 }
3982 
3983 int iscsi_target_rx_thread(void *arg)
3984 {
3985 	int rc;
3986 	struct iscsi_conn *conn = arg;
3987 	bool conn_freed = false;
3988 
3989 	/*
3990 	 * Allow ourselves to be interrupted by SIGINT so that a
3991 	 * connection recovery / failure event can be triggered externally.
3992 	 */
3993 	allow_signal(SIGINT);
3994 	/*
3995 	 * Wait for iscsi_post_login_handler() to complete before allowing
3996 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
3997 	 */
3998 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
3999 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4000 		goto out;
4001 
4002 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4003 		return 0;
4004 
4005 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4006 
4007 	if (!signal_pending(current))
4008 		atomic_set(&conn->transport_failed, 1);
4009 	iscsit_take_action_for_connection_exit(conn, &conn_freed);
4010 
4011 out:
4012 	if (!conn_freed) {
4013 		while (!kthread_should_stop()) {
4014 			msleep(100);
4015 		}
4016 	}
4017 
4018 	return 0;
4019 }
4020 
4021 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4022 {
4023 	LIST_HEAD(tmp_list);
4024 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4025 	struct iscsi_session *sess = conn->sess;
4026 	/*
4027 	 * We expect this function to only ever be called from either RX or TX
4028 	 * thread context via iscsit_close_connection() once the other context
4029 	 * has been reset -> returned sleeping pre-handler state.
4030 	 */
4031 	spin_lock_bh(&conn->cmd_lock);
4032 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4033 
4034 	list_for_each_entry(cmd, &tmp_list, i_conn_node) {
4035 		struct se_cmd *se_cmd = &cmd->se_cmd;
4036 
4037 		if (se_cmd->se_tfo != NULL) {
4038 			spin_lock_irq(&se_cmd->t_state_lock);
4039 			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4040 			spin_unlock_irq(&se_cmd->t_state_lock);
4041 		}
4042 	}
4043 	spin_unlock_bh(&conn->cmd_lock);
4044 
4045 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4046 		list_del_init(&cmd->i_conn_node);
4047 
4048 		iscsit_increment_maxcmdsn(cmd, sess);
4049 		iscsit_free_cmd(cmd, true);
4050 
4051 	}
4052 }
4053 
4054 static void iscsit_stop_timers_for_cmds(
4055 	struct iscsi_conn *conn)
4056 {
4057 	struct iscsi_cmd *cmd;
4058 
4059 	spin_lock_bh(&conn->cmd_lock);
4060 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4061 		if (cmd->data_direction == DMA_TO_DEVICE)
4062 			iscsit_stop_dataout_timer(cmd);
4063 	}
4064 	spin_unlock_bh(&conn->cmd_lock);
4065 }
4066 
4067 int iscsit_close_connection(
4068 	struct iscsi_conn *conn)
4069 {
4070 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4071 	struct iscsi_session	*sess = conn->sess;
4072 
4073 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4074 		" %u\n", conn->cid, sess->sid);
4075 	/*
4076 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4077 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4078 	 * sleeping and the logout response never got sent because the
4079 	 * connection failed.
4080 	 *
4081 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4082 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4083 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4084 	 * and to avoid iscsi_conn pointer dereference in iser-target code.
4085 	 */
4086 	if (!conn->conn_transport->rdma_shutdown)
4087 		complete(&conn->conn_logout_comp);
4088 
4089 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4090 		if (conn->tx_thread &&
4091 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4092 			send_sig(SIGINT, conn->tx_thread, 1);
4093 			kthread_stop(conn->tx_thread);
4094 		}
4095 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4096 		if (conn->rx_thread &&
4097 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4098 			send_sig(SIGINT, conn->rx_thread, 1);
4099 			kthread_stop(conn->rx_thread);
4100 		}
4101 	}
4102 
4103 	spin_lock(&iscsit_global->ts_bitmap_lock);
4104 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4105 			      get_order(1));
4106 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4107 
4108 	iscsit_stop_timers_for_cmds(conn);
4109 	iscsit_stop_nopin_response_timer(conn);
4110 	iscsit_stop_nopin_timer(conn);
4111 
4112 	if (conn->conn_transport->iscsit_wait_conn)
4113 		conn->conn_transport->iscsit_wait_conn(conn);
4114 
4115 	/*
4116 	 * During Connection recovery drop unacknowledged out of order
4117 	 * commands for this connection, and prepare the other commands
4118 	 * for reallegiance.
4119 	 *
4120 	 * During normal operation clear the out of order commands (but
4121 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4122 	 * struct iscsi_cmds.
4123 	 */
4124 	if (atomic_read(&conn->connection_recovery)) {
4125 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4126 		iscsit_prepare_cmds_for_reallegiance(conn);
4127 	} else {
4128 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4129 		iscsit_release_commands_from_conn(conn);
4130 	}
4131 	iscsit_free_queue_reqs_for_conn(conn);
4132 
4133 	/*
4134 	 * Handle decrementing session or connection usage count if
4135 	 * a logout response was not able to be sent because the
4136 	 * connection failed.  Fall back to Session Recovery here.
4137 	 */
4138 	if (atomic_read(&conn->conn_logout_remove)) {
4139 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4140 			iscsit_dec_conn_usage_count(conn);
4141 			iscsit_dec_session_usage_count(sess);
4142 		}
4143 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4144 			iscsit_dec_conn_usage_count(conn);
4145 
4146 		atomic_set(&conn->conn_logout_remove, 0);
4147 		atomic_set(&sess->session_reinstatement, 0);
4148 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4149 	}
4150 
4151 	spin_lock_bh(&sess->conn_lock);
4152 	list_del(&conn->conn_list);
4153 
4154 	/*
4155 	 * Attempt to let the Initiator know this connection failed by
4156 	 * sending an Connection Dropped Async Message on another
4157 	 * active connection.
4158 	 */
4159 	if (atomic_read(&conn->connection_recovery))
4160 		iscsit_build_conn_drop_async_message(conn);
4161 
4162 	spin_unlock_bh(&sess->conn_lock);
4163 
4164 	/*
4165 	 * If connection reinstatement is being performed on this connection,
4166 	 * up the connection reinstatement semaphore that is being blocked on
4167 	 * in iscsit_cause_connection_reinstatement().
4168 	 */
4169 	spin_lock_bh(&conn->state_lock);
4170 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4171 		spin_unlock_bh(&conn->state_lock);
4172 		complete(&conn->conn_wait_comp);
4173 		wait_for_completion(&conn->conn_post_wait_comp);
4174 		spin_lock_bh(&conn->state_lock);
4175 	}
4176 
4177 	/*
4178 	 * If connection reinstatement is being performed on this connection
4179 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4180 	 * connection wait rcfr semaphore that is being blocked on
4181 	 * an iscsit_connection_reinstatement_rcfr().
4182 	 */
4183 	if (atomic_read(&conn->connection_wait_rcfr)) {
4184 		spin_unlock_bh(&conn->state_lock);
4185 		complete(&conn->conn_wait_rcfr_comp);
4186 		wait_for_completion(&conn->conn_post_wait_comp);
4187 		spin_lock_bh(&conn->state_lock);
4188 	}
4189 	atomic_set(&conn->connection_reinstatement, 1);
4190 	spin_unlock_bh(&conn->state_lock);
4191 
4192 	/*
4193 	 * If any other processes are accessing this connection pointer we
4194 	 * must wait until they have completed.
4195 	 */
4196 	iscsit_check_conn_usage_count(conn);
4197 
4198 	ahash_request_free(conn->conn_tx_hash);
4199 	if (conn->conn_rx_hash) {
4200 		struct crypto_ahash *tfm;
4201 
4202 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4203 		ahash_request_free(conn->conn_rx_hash);
4204 		crypto_free_ahash(tfm);
4205 	}
4206 
4207 	if (conn->sock)
4208 		sock_release(conn->sock);
4209 
4210 	if (conn->conn_transport->iscsit_free_conn)
4211 		conn->conn_transport->iscsit_free_conn(conn);
4212 
4213 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4214 	conn->conn_state = TARG_CONN_STATE_FREE;
4215 	iscsit_free_conn(conn);
4216 
4217 	spin_lock_bh(&sess->conn_lock);
4218 	atomic_dec(&sess->nconn);
4219 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4220 		" %s\n", atomic_read(&sess->nconn),
4221 		sess->sess_ops->InitiatorName);
4222 	/*
4223 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4224 	 * Session that they all fail.
4225 	 */
4226 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4227 	     !atomic_read(&sess->session_logout))
4228 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4229 
4230 	/*
4231 	 * If this was not the last connection in the session, and we are
4232 	 * performing session reinstatement or falling back to ERL=0, call
4233 	 * iscsit_stop_session() without sleeping to shutdown the other
4234 	 * active connections.
4235 	 */
4236 	if (atomic_read(&sess->nconn)) {
4237 		if (!atomic_read(&sess->session_reinstatement) &&
4238 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4239 			spin_unlock_bh(&sess->conn_lock);
4240 			return 0;
4241 		}
4242 		if (!atomic_read(&sess->session_stop_active)) {
4243 			atomic_set(&sess->session_stop_active, 1);
4244 			spin_unlock_bh(&sess->conn_lock);
4245 			iscsit_stop_session(sess, 0, 0);
4246 			return 0;
4247 		}
4248 		spin_unlock_bh(&sess->conn_lock);
4249 		return 0;
4250 	}
4251 
4252 	/*
4253 	 * If this was the last connection in the session and one of the
4254 	 * following is occurring:
4255 	 *
4256 	 * Session Reinstatement is not being performed, and are falling back
4257 	 * to ERL=0 call iscsit_close_session().
4258 	 *
4259 	 * Session Logout was requested.  iscsit_close_session() will be called
4260 	 * elsewhere.
4261 	 *
4262 	 * Session Continuation is not being performed, start the Time2Retain
4263 	 * handler and check if sleep_on_sess_wait_sem is active.
4264 	 */
4265 	if (!atomic_read(&sess->session_reinstatement) &&
4266 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4267 		spin_unlock_bh(&sess->conn_lock);
4268 		iscsit_close_session(sess);
4269 
4270 		return 0;
4271 	} else if (atomic_read(&sess->session_logout)) {
4272 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4273 		sess->session_state = TARG_SESS_STATE_FREE;
4274 		spin_unlock_bh(&sess->conn_lock);
4275 
4276 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4277 			complete(&sess->session_wait_comp);
4278 
4279 		return 0;
4280 	} else {
4281 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4282 		sess->session_state = TARG_SESS_STATE_FAILED;
4283 
4284 		if (!atomic_read(&sess->session_continuation)) {
4285 			spin_unlock_bh(&sess->conn_lock);
4286 			iscsit_start_time2retain_handler(sess);
4287 		} else
4288 			spin_unlock_bh(&sess->conn_lock);
4289 
4290 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4291 			complete(&sess->session_wait_comp);
4292 
4293 		return 0;
4294 	}
4295 }
4296 
4297 /*
4298  * If the iSCSI Session for the iSCSI Initiator Node exists,
4299  * forcefully shutdown the iSCSI NEXUS.
4300  */
4301 int iscsit_close_session(struct iscsi_session *sess)
4302 {
4303 	struct iscsi_portal_group *tpg = sess->tpg;
4304 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4305 
4306 	if (atomic_read(&sess->nconn)) {
4307 		pr_err("%d connection(s) still exist for iSCSI session"
4308 			" to %s\n", atomic_read(&sess->nconn),
4309 			sess->sess_ops->InitiatorName);
4310 		BUG();
4311 	}
4312 
4313 	spin_lock_bh(&se_tpg->session_lock);
4314 	atomic_set(&sess->session_logout, 1);
4315 	atomic_set(&sess->session_reinstatement, 1);
4316 	iscsit_stop_time2retain_timer(sess);
4317 	spin_unlock_bh(&se_tpg->session_lock);
4318 
4319 	/*
4320 	 * transport_deregister_session_configfs() will clear the
4321 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4322 	 * can be setting it again with __transport_register_session() in
4323 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4324 	 * completes in iscsi_np context.
4325 	 */
4326 	transport_deregister_session_configfs(sess->se_sess);
4327 
4328 	/*
4329 	 * If any other processes are accessing this session pointer we must
4330 	 * wait until they have completed.  If we are in an interrupt (the
4331 	 * time2retain handler) and contain and active session usage count we
4332 	 * restart the timer and exit.
4333 	 */
4334 	if (!in_interrupt()) {
4335 		if (iscsit_check_session_usage_count(sess) == 1)
4336 			iscsit_stop_session(sess, 1, 1);
4337 	} else {
4338 		if (iscsit_check_session_usage_count(sess) == 2) {
4339 			atomic_set(&sess->session_logout, 0);
4340 			iscsit_start_time2retain_handler(sess);
4341 			return 0;
4342 		}
4343 	}
4344 
4345 	transport_deregister_session(sess->se_sess);
4346 
4347 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4348 		iscsit_free_connection_recovery_entries(sess);
4349 
4350 	iscsit_free_all_ooo_cmdsns(sess);
4351 
4352 	spin_lock_bh(&se_tpg->session_lock);
4353 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4354 	sess->session_state = TARG_SESS_STATE_FREE;
4355 	pr_debug("Released iSCSI session from node: %s\n",
4356 			sess->sess_ops->InitiatorName);
4357 	tpg->nsessions--;
4358 	if (tpg->tpg_tiqn)
4359 		tpg->tpg_tiqn->tiqn_nsessions--;
4360 
4361 	pr_debug("Decremented number of active iSCSI Sessions on"
4362 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4363 
4364 	ida_free(&sess_ida, sess->session_index);
4365 	kfree(sess->sess_ops);
4366 	sess->sess_ops = NULL;
4367 	spin_unlock_bh(&se_tpg->session_lock);
4368 
4369 	kfree(sess);
4370 	return 0;
4371 }
4372 
4373 static void iscsit_logout_post_handler_closesession(
4374 	struct iscsi_conn *conn)
4375 {
4376 	struct iscsi_session *sess = conn->sess;
4377 	int sleep = 1;
4378 	/*
4379 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4380 	 * context during session logout, so clear tx_thread_active and
4381 	 * sleep if iscsit_close_connection() has not already occured.
4382 	 *
4383 	 * Since iser-target invokes this logic from it's own workqueue,
4384 	 * always sleep waiting for RX/TX thread shutdown to complete
4385 	 * within iscsit_close_connection().
4386 	 */
4387 	if (!conn->conn_transport->rdma_shutdown) {
4388 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4389 		if (!sleep)
4390 			return;
4391 	}
4392 
4393 	atomic_set(&conn->conn_logout_remove, 0);
4394 	complete(&conn->conn_logout_comp);
4395 
4396 	iscsit_dec_conn_usage_count(conn);
4397 	iscsit_stop_session(sess, sleep, sleep);
4398 	iscsit_dec_session_usage_count(sess);
4399 	iscsit_close_session(sess);
4400 }
4401 
4402 static void iscsit_logout_post_handler_samecid(
4403 	struct iscsi_conn *conn)
4404 {
4405 	int sleep = 1;
4406 
4407 	if (!conn->conn_transport->rdma_shutdown) {
4408 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4409 		if (!sleep)
4410 			return;
4411 	}
4412 
4413 	atomic_set(&conn->conn_logout_remove, 0);
4414 	complete(&conn->conn_logout_comp);
4415 
4416 	iscsit_cause_connection_reinstatement(conn, sleep);
4417 	iscsit_dec_conn_usage_count(conn);
4418 }
4419 
4420 static void iscsit_logout_post_handler_diffcid(
4421 	struct iscsi_conn *conn,
4422 	u16 cid)
4423 {
4424 	struct iscsi_conn *l_conn;
4425 	struct iscsi_session *sess = conn->sess;
4426 	bool conn_found = false;
4427 
4428 	if (!sess)
4429 		return;
4430 
4431 	spin_lock_bh(&sess->conn_lock);
4432 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4433 		if (l_conn->cid == cid) {
4434 			iscsit_inc_conn_usage_count(l_conn);
4435 			conn_found = true;
4436 			break;
4437 		}
4438 	}
4439 	spin_unlock_bh(&sess->conn_lock);
4440 
4441 	if (!conn_found)
4442 		return;
4443 
4444 	if (l_conn->sock)
4445 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4446 
4447 	spin_lock_bh(&l_conn->state_lock);
4448 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4449 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4450 	spin_unlock_bh(&l_conn->state_lock);
4451 
4452 	iscsit_cause_connection_reinstatement(l_conn, 1);
4453 	iscsit_dec_conn_usage_count(l_conn);
4454 }
4455 
4456 /*
4457  *	Return of 0 causes the TX thread to restart.
4458  */
4459 int iscsit_logout_post_handler(
4460 	struct iscsi_cmd *cmd,
4461 	struct iscsi_conn *conn)
4462 {
4463 	int ret = 0;
4464 
4465 	switch (cmd->logout_reason) {
4466 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4467 		switch (cmd->logout_response) {
4468 		case ISCSI_LOGOUT_SUCCESS:
4469 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4470 		default:
4471 			iscsit_logout_post_handler_closesession(conn);
4472 			break;
4473 		}
4474 		ret = 0;
4475 		break;
4476 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4477 		if (conn->cid == cmd->logout_cid) {
4478 			switch (cmd->logout_response) {
4479 			case ISCSI_LOGOUT_SUCCESS:
4480 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4481 			default:
4482 				iscsit_logout_post_handler_samecid(conn);
4483 				break;
4484 			}
4485 			ret = 0;
4486 		} else {
4487 			switch (cmd->logout_response) {
4488 			case ISCSI_LOGOUT_SUCCESS:
4489 				iscsit_logout_post_handler_diffcid(conn,
4490 					cmd->logout_cid);
4491 				break;
4492 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4493 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4494 			default:
4495 				break;
4496 			}
4497 			ret = 1;
4498 		}
4499 		break;
4500 	case ISCSI_LOGOUT_REASON_RECOVERY:
4501 		switch (cmd->logout_response) {
4502 		case ISCSI_LOGOUT_SUCCESS:
4503 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4504 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4505 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4506 		default:
4507 			break;
4508 		}
4509 		ret = 1;
4510 		break;
4511 	default:
4512 		break;
4513 
4514 	}
4515 	return ret;
4516 }
4517 EXPORT_SYMBOL(iscsit_logout_post_handler);
4518 
4519 void iscsit_fail_session(struct iscsi_session *sess)
4520 {
4521 	struct iscsi_conn *conn;
4522 
4523 	spin_lock_bh(&sess->conn_lock);
4524 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4525 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4526 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4527 	}
4528 	spin_unlock_bh(&sess->conn_lock);
4529 
4530 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4531 	sess->session_state = TARG_SESS_STATE_FAILED;
4532 }
4533 
4534 int iscsit_free_session(struct iscsi_session *sess)
4535 {
4536 	u16 conn_count = atomic_read(&sess->nconn);
4537 	struct iscsi_conn *conn, *conn_tmp = NULL;
4538 	int is_last;
4539 
4540 	spin_lock_bh(&sess->conn_lock);
4541 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4542 
4543 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4544 			conn_list) {
4545 		if (conn_count == 0)
4546 			break;
4547 
4548 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4549 			is_last = 1;
4550 		} else {
4551 			iscsit_inc_conn_usage_count(conn_tmp);
4552 			is_last = 0;
4553 		}
4554 		iscsit_inc_conn_usage_count(conn);
4555 
4556 		spin_unlock_bh(&sess->conn_lock);
4557 		iscsit_cause_connection_reinstatement(conn, 1);
4558 		spin_lock_bh(&sess->conn_lock);
4559 
4560 		iscsit_dec_conn_usage_count(conn);
4561 		if (is_last == 0)
4562 			iscsit_dec_conn_usage_count(conn_tmp);
4563 
4564 		conn_count--;
4565 	}
4566 
4567 	if (atomic_read(&sess->nconn)) {
4568 		spin_unlock_bh(&sess->conn_lock);
4569 		wait_for_completion(&sess->session_wait_comp);
4570 	} else
4571 		spin_unlock_bh(&sess->conn_lock);
4572 
4573 	iscsit_close_session(sess);
4574 	return 0;
4575 }
4576 
4577 void iscsit_stop_session(
4578 	struct iscsi_session *sess,
4579 	int session_sleep,
4580 	int connection_sleep)
4581 {
4582 	u16 conn_count = atomic_read(&sess->nconn);
4583 	struct iscsi_conn *conn, *conn_tmp = NULL;
4584 	int is_last;
4585 
4586 	spin_lock_bh(&sess->conn_lock);
4587 	if (session_sleep)
4588 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4589 
4590 	if (connection_sleep) {
4591 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4592 				conn_list) {
4593 			if (conn_count == 0)
4594 				break;
4595 
4596 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4597 				is_last = 1;
4598 			} else {
4599 				iscsit_inc_conn_usage_count(conn_tmp);
4600 				is_last = 0;
4601 			}
4602 			iscsit_inc_conn_usage_count(conn);
4603 
4604 			spin_unlock_bh(&sess->conn_lock);
4605 			iscsit_cause_connection_reinstatement(conn, 1);
4606 			spin_lock_bh(&sess->conn_lock);
4607 
4608 			iscsit_dec_conn_usage_count(conn);
4609 			if (is_last == 0)
4610 				iscsit_dec_conn_usage_count(conn_tmp);
4611 			conn_count--;
4612 		}
4613 	} else {
4614 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4615 			iscsit_cause_connection_reinstatement(conn, 0);
4616 	}
4617 
4618 	if (session_sleep && atomic_read(&sess->nconn)) {
4619 		spin_unlock_bh(&sess->conn_lock);
4620 		wait_for_completion(&sess->session_wait_comp);
4621 	} else
4622 		spin_unlock_bh(&sess->conn_lock);
4623 }
4624 
4625 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4626 {
4627 	struct iscsi_session *sess;
4628 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4629 	struct se_session *se_sess, *se_sess_tmp;
4630 	LIST_HEAD(free_list);
4631 	int session_count = 0;
4632 
4633 	spin_lock_bh(&se_tpg->session_lock);
4634 	if (tpg->nsessions && !force) {
4635 		spin_unlock_bh(&se_tpg->session_lock);
4636 		return -1;
4637 	}
4638 
4639 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4640 			sess_list) {
4641 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4642 
4643 		spin_lock(&sess->conn_lock);
4644 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4645 		    atomic_read(&sess->session_logout) ||
4646 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4647 			spin_unlock(&sess->conn_lock);
4648 			continue;
4649 		}
4650 		atomic_set(&sess->session_reinstatement, 1);
4651 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4652 		spin_unlock(&sess->conn_lock);
4653 
4654 		list_move_tail(&se_sess->sess_list, &free_list);
4655 	}
4656 	spin_unlock_bh(&se_tpg->session_lock);
4657 
4658 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4659 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4660 
4661 		iscsit_free_session(sess);
4662 		session_count++;
4663 	}
4664 
4665 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4666 			" Group: %hu\n", session_count, tpg->tpgt);
4667 	return 0;
4668 }
4669 
4670 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4671 MODULE_VERSION("4.1.x");
4672 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4673 MODULE_LICENSE("GPL");
4674 
4675 module_init(iscsi_target_init_module);
4676 module_exit(iscsi_target_cleanup_module);
4677