xref: /linux/drivers/target/iscsi/iscsi_target.c (revision b7019ac550eb3916f34d79db583e9b7ea2524afa)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * This file contains main functions related to the iSCSI Target Core Driver.
4  *
5  * (c) Copyright 2007-2013 Datera, Inc.
6  *
7  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
8  *
9  ******************************************************************************/
10 
11 #include <crypto/hash.h>
12 #include <linux/string.h>
13 #include <linux/kthread.h>
14 #include <linux/completion.h>
15 #include <linux/module.h>
16 #include <linux/vmalloc.h>
17 #include <linux/idr.h>
18 #include <linux/delay.h>
19 #include <linux/sched/signal.h>
20 #include <asm/unaligned.h>
21 #include <linux/inet.h>
22 #include <net/ipv6.h>
23 #include <scsi/scsi_proto.h>
24 #include <scsi/iscsi_proto.h>
25 #include <scsi/scsi_tcq.h>
26 #include <target/target_core_base.h>
27 #include <target/target_core_fabric.h>
28 
29 #include <target/iscsi/iscsi_target_core.h>
30 #include "iscsi_target_parameters.h"
31 #include "iscsi_target_seq_pdu_list.h"
32 #include "iscsi_target_datain_values.h"
33 #include "iscsi_target_erl0.h"
34 #include "iscsi_target_erl1.h"
35 #include "iscsi_target_erl2.h"
36 #include "iscsi_target_login.h"
37 #include "iscsi_target_tmr.h"
38 #include "iscsi_target_tpg.h"
39 #include "iscsi_target_util.h"
40 #include "iscsi_target.h"
41 #include "iscsi_target_device.h"
42 #include <target/iscsi/iscsi_target_stat.h>
43 
44 #include <target/iscsi/iscsi_transport.h>
45 
46 static LIST_HEAD(g_tiqn_list);
47 static LIST_HEAD(g_np_list);
48 static DEFINE_SPINLOCK(tiqn_lock);
49 static DEFINE_MUTEX(np_lock);
50 
51 static struct idr tiqn_idr;
52 DEFINE_IDA(sess_ida);
53 struct mutex auth_id_lock;
54 
55 struct iscsit_global *iscsit_global;
56 
57 struct kmem_cache *lio_qr_cache;
58 struct kmem_cache *lio_dr_cache;
59 struct kmem_cache *lio_ooo_cache;
60 struct kmem_cache *lio_r2t_cache;
61 
62 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
63 			struct iscsi_scsi_req *, u32);
64 
65 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
66 {
67 	struct iscsi_tiqn *tiqn = NULL;
68 
69 	spin_lock(&tiqn_lock);
70 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
71 		if (!strcmp(tiqn->tiqn, buf)) {
72 
73 			spin_lock(&tiqn->tiqn_state_lock);
74 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
75 				tiqn->tiqn_access_count++;
76 				spin_unlock(&tiqn->tiqn_state_lock);
77 				spin_unlock(&tiqn_lock);
78 				return tiqn;
79 			}
80 			spin_unlock(&tiqn->tiqn_state_lock);
81 		}
82 	}
83 	spin_unlock(&tiqn_lock);
84 
85 	return NULL;
86 }
87 
88 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
89 {
90 	spin_lock(&tiqn->tiqn_state_lock);
91 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
92 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
93 		spin_unlock(&tiqn->tiqn_state_lock);
94 		return 0;
95 	}
96 	spin_unlock(&tiqn->tiqn_state_lock);
97 
98 	return -1;
99 }
100 
101 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
102 {
103 	spin_lock(&tiqn->tiqn_state_lock);
104 	tiqn->tiqn_access_count--;
105 	spin_unlock(&tiqn->tiqn_state_lock);
106 }
107 
108 /*
109  * Note that IQN formatting is expected to be done in userspace, and
110  * no explict IQN format checks are done here.
111  */
112 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
113 {
114 	struct iscsi_tiqn *tiqn = NULL;
115 	int ret;
116 
117 	if (strlen(buf) >= ISCSI_IQN_LEN) {
118 		pr_err("Target IQN exceeds %d bytes\n",
119 				ISCSI_IQN_LEN);
120 		return ERR_PTR(-EINVAL);
121 	}
122 
123 	tiqn = kzalloc(sizeof(*tiqn), GFP_KERNEL);
124 	if (!tiqn)
125 		return ERR_PTR(-ENOMEM);
126 
127 	sprintf(tiqn->tiqn, "%s", buf);
128 	INIT_LIST_HEAD(&tiqn->tiqn_list);
129 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
130 	spin_lock_init(&tiqn->tiqn_state_lock);
131 	spin_lock_init(&tiqn->tiqn_tpg_lock);
132 	spin_lock_init(&tiqn->sess_err_stats.lock);
133 	spin_lock_init(&tiqn->login_stats.lock);
134 	spin_lock_init(&tiqn->logout_stats.lock);
135 
136 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
137 
138 	idr_preload(GFP_KERNEL);
139 	spin_lock(&tiqn_lock);
140 
141 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
142 	if (ret < 0) {
143 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
144 		spin_unlock(&tiqn_lock);
145 		idr_preload_end();
146 		kfree(tiqn);
147 		return ERR_PTR(ret);
148 	}
149 	tiqn->tiqn_index = ret;
150 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
151 
152 	spin_unlock(&tiqn_lock);
153 	idr_preload_end();
154 
155 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
156 
157 	return tiqn;
158 
159 }
160 
161 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
162 {
163 	/*
164 	 * Wait for accesses to said struct iscsi_tiqn to end.
165 	 */
166 	spin_lock(&tiqn->tiqn_state_lock);
167 	while (tiqn->tiqn_access_count != 0) {
168 		spin_unlock(&tiqn->tiqn_state_lock);
169 		msleep(10);
170 		spin_lock(&tiqn->tiqn_state_lock);
171 	}
172 	spin_unlock(&tiqn->tiqn_state_lock);
173 }
174 
175 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
176 {
177 	/*
178 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
179 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
180 	 * attempts to access this struct iscsi_tiqn will fail from both transport
181 	 * fabric and control code paths.
182 	 */
183 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
184 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
185 		return;
186 	}
187 
188 	iscsit_wait_for_tiqn(tiqn);
189 
190 	spin_lock(&tiqn_lock);
191 	list_del(&tiqn->tiqn_list);
192 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
193 	spin_unlock(&tiqn_lock);
194 
195 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
196 			tiqn->tiqn);
197 	kfree(tiqn);
198 }
199 
200 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
201 {
202 	int ret;
203 	/*
204 	 * Determine if the network portal is accepting storage traffic.
205 	 */
206 	spin_lock_bh(&np->np_thread_lock);
207 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
208 		spin_unlock_bh(&np->np_thread_lock);
209 		return -1;
210 	}
211 	spin_unlock_bh(&np->np_thread_lock);
212 	/*
213 	 * Determine if the portal group is accepting storage traffic.
214 	 */
215 	spin_lock_bh(&tpg->tpg_state_lock);
216 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
217 		spin_unlock_bh(&tpg->tpg_state_lock);
218 		return -1;
219 	}
220 	spin_unlock_bh(&tpg->tpg_state_lock);
221 
222 	/*
223 	 * Here we serialize access across the TIQN+TPG Tuple.
224 	 */
225 	ret = down_interruptible(&tpg->np_login_sem);
226 	if (ret != 0)
227 		return -1;
228 
229 	spin_lock_bh(&tpg->tpg_state_lock);
230 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
231 		spin_unlock_bh(&tpg->tpg_state_lock);
232 		up(&tpg->np_login_sem);
233 		return -1;
234 	}
235 	spin_unlock_bh(&tpg->tpg_state_lock);
236 
237 	return 0;
238 }
239 
240 void iscsit_login_kref_put(struct kref *kref)
241 {
242 	struct iscsi_tpg_np *tpg_np = container_of(kref,
243 				struct iscsi_tpg_np, tpg_np_kref);
244 
245 	complete(&tpg_np->tpg_np_comp);
246 }
247 
248 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
249 		       struct iscsi_tpg_np *tpg_np)
250 {
251 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
252 
253 	up(&tpg->np_login_sem);
254 
255 	if (tpg_np)
256 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
257 
258 	if (tiqn)
259 		iscsit_put_tiqn_for_login(tiqn);
260 
261 	return 0;
262 }
263 
264 bool iscsit_check_np_match(
265 	struct sockaddr_storage *sockaddr,
266 	struct iscsi_np *np,
267 	int network_transport)
268 {
269 	struct sockaddr_in *sock_in, *sock_in_e;
270 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
271 	bool ip_match = false;
272 	u16 port, port_e;
273 
274 	if (sockaddr->ss_family == AF_INET6) {
275 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
276 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
277 
278 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
279 			    &sock_in6_e->sin6_addr.in6_u,
280 			    sizeof(struct in6_addr)))
281 			ip_match = true;
282 
283 		port = ntohs(sock_in6->sin6_port);
284 		port_e = ntohs(sock_in6_e->sin6_port);
285 	} else {
286 		sock_in = (struct sockaddr_in *)sockaddr;
287 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
288 
289 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
290 			ip_match = true;
291 
292 		port = ntohs(sock_in->sin_port);
293 		port_e = ntohs(sock_in_e->sin_port);
294 	}
295 
296 	if (ip_match && (port_e == port) &&
297 	    (np->np_network_transport == network_transport))
298 		return true;
299 
300 	return false;
301 }
302 
303 static struct iscsi_np *iscsit_get_np(
304 	struct sockaddr_storage *sockaddr,
305 	int network_transport)
306 {
307 	struct iscsi_np *np;
308 	bool match;
309 
310 	lockdep_assert_held(&np_lock);
311 
312 	list_for_each_entry(np, &g_np_list, np_list) {
313 		spin_lock_bh(&np->np_thread_lock);
314 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
315 			spin_unlock_bh(&np->np_thread_lock);
316 			continue;
317 		}
318 
319 		match = iscsit_check_np_match(sockaddr, np, network_transport);
320 		if (match) {
321 			/*
322 			 * Increment the np_exports reference count now to
323 			 * prevent iscsit_del_np() below from being called
324 			 * while iscsi_tpg_add_network_portal() is called.
325 			 */
326 			np->np_exports++;
327 			spin_unlock_bh(&np->np_thread_lock);
328 			return np;
329 		}
330 		spin_unlock_bh(&np->np_thread_lock);
331 	}
332 
333 	return NULL;
334 }
335 
336 struct iscsi_np *iscsit_add_np(
337 	struct sockaddr_storage *sockaddr,
338 	int network_transport)
339 {
340 	struct iscsi_np *np;
341 	int ret;
342 
343 	mutex_lock(&np_lock);
344 
345 	/*
346 	 * Locate the existing struct iscsi_np if already active..
347 	 */
348 	np = iscsit_get_np(sockaddr, network_transport);
349 	if (np) {
350 		mutex_unlock(&np_lock);
351 		return np;
352 	}
353 
354 	np = kzalloc(sizeof(*np), GFP_KERNEL);
355 	if (!np) {
356 		mutex_unlock(&np_lock);
357 		return ERR_PTR(-ENOMEM);
358 	}
359 
360 	np->np_flags |= NPF_IP_NETWORK;
361 	np->np_network_transport = network_transport;
362 	spin_lock_init(&np->np_thread_lock);
363 	init_completion(&np->np_restart_comp);
364 	INIT_LIST_HEAD(&np->np_list);
365 
366 	timer_setup(&np->np_login_timer, iscsi_handle_login_thread_timeout, 0);
367 
368 	ret = iscsi_target_setup_login_socket(np, sockaddr);
369 	if (ret != 0) {
370 		kfree(np);
371 		mutex_unlock(&np_lock);
372 		return ERR_PTR(ret);
373 	}
374 
375 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
376 	if (IS_ERR(np->np_thread)) {
377 		pr_err("Unable to create kthread: iscsi_np\n");
378 		ret = PTR_ERR(np->np_thread);
379 		kfree(np);
380 		mutex_unlock(&np_lock);
381 		return ERR_PTR(ret);
382 	}
383 	/*
384 	 * Increment the np_exports reference count now to prevent
385 	 * iscsit_del_np() below from being run while a new call to
386 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
387 	 * active.  We don't need to hold np->np_thread_lock at this
388 	 * point because iscsi_np has not been added to g_np_list yet.
389 	 */
390 	np->np_exports = 1;
391 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
392 
393 	list_add_tail(&np->np_list, &g_np_list);
394 	mutex_unlock(&np_lock);
395 
396 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
397 		&np->np_sockaddr, np->np_transport->name);
398 
399 	return np;
400 }
401 
402 int iscsit_reset_np_thread(
403 	struct iscsi_np *np,
404 	struct iscsi_tpg_np *tpg_np,
405 	struct iscsi_portal_group *tpg,
406 	bool shutdown)
407 {
408 	spin_lock_bh(&np->np_thread_lock);
409 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
410 		spin_unlock_bh(&np->np_thread_lock);
411 		return 0;
412 	}
413 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
414 	atomic_inc(&np->np_reset_count);
415 
416 	if (np->np_thread) {
417 		spin_unlock_bh(&np->np_thread_lock);
418 		send_sig(SIGINT, np->np_thread, 1);
419 		wait_for_completion(&np->np_restart_comp);
420 		spin_lock_bh(&np->np_thread_lock);
421 	}
422 	spin_unlock_bh(&np->np_thread_lock);
423 
424 	if (tpg_np && shutdown) {
425 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
426 
427 		wait_for_completion(&tpg_np->tpg_np_comp);
428 	}
429 
430 	return 0;
431 }
432 
433 static void iscsit_free_np(struct iscsi_np *np)
434 {
435 	if (np->np_socket)
436 		sock_release(np->np_socket);
437 }
438 
439 int iscsit_del_np(struct iscsi_np *np)
440 {
441 	spin_lock_bh(&np->np_thread_lock);
442 	np->np_exports--;
443 	if (np->np_exports) {
444 		np->enabled = true;
445 		spin_unlock_bh(&np->np_thread_lock);
446 		return 0;
447 	}
448 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
449 	spin_unlock_bh(&np->np_thread_lock);
450 
451 	if (np->np_thread) {
452 		/*
453 		 * We need to send the signal to wakeup Linux/Net
454 		 * which may be sleeping in sock_accept()..
455 		 */
456 		send_sig(SIGINT, np->np_thread, 1);
457 		kthread_stop(np->np_thread);
458 		np->np_thread = NULL;
459 	}
460 
461 	np->np_transport->iscsit_free_np(np);
462 
463 	mutex_lock(&np_lock);
464 	list_del(&np->np_list);
465 	mutex_unlock(&np_lock);
466 
467 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
468 		&np->np_sockaddr, np->np_transport->name);
469 
470 	iscsit_put_transport(np->np_transport);
471 	kfree(np);
472 	return 0;
473 }
474 
475 static void iscsit_get_rx_pdu(struct iscsi_conn *);
476 
477 int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
478 {
479 	return iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
480 }
481 EXPORT_SYMBOL(iscsit_queue_rsp);
482 
483 void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
484 {
485 	spin_lock_bh(&conn->cmd_lock);
486 	if (!list_empty(&cmd->i_conn_node) &&
487 	    !(cmd->se_cmd.transport_state & CMD_T_FABRIC_STOP))
488 		list_del_init(&cmd->i_conn_node);
489 	spin_unlock_bh(&conn->cmd_lock);
490 
491 	__iscsit_free_cmd(cmd, true);
492 }
493 EXPORT_SYMBOL(iscsit_aborted_task);
494 
495 static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
496 				      u32, u32, const void *, void *);
497 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *);
498 
499 static int
500 iscsit_xmit_nondatain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
501 			  const void *data_buf, u32 data_buf_len)
502 {
503 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
504 	struct kvec *iov;
505 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
506 	int ret;
507 
508 	iov = &cmd->iov_misc[0];
509 	iov[niov].iov_base	= cmd->pdu;
510 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
511 
512 	if (conn->conn_ops->HeaderDigest) {
513 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
514 
515 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
516 					  ISCSI_HDR_LEN, 0, NULL,
517 					  header_digest);
518 
519 		iov[0].iov_len += ISCSI_CRC_LEN;
520 		tx_size += ISCSI_CRC_LEN;
521 		pr_debug("Attaching CRC32C HeaderDigest"
522 			 " to opcode 0x%x 0x%08x\n",
523 			 hdr->opcode, *header_digest);
524 	}
525 
526 	if (data_buf_len) {
527 		u32 padding = ((-data_buf_len) & 3);
528 
529 		iov[niov].iov_base	= (void *)data_buf;
530 		iov[niov++].iov_len	= data_buf_len;
531 		tx_size += data_buf_len;
532 
533 		if (padding != 0) {
534 			iov[niov].iov_base = &cmd->pad_bytes;
535 			iov[niov++].iov_len = padding;
536 			tx_size += padding;
537 			pr_debug("Attaching %u additional"
538 				 " padding bytes.\n", padding);
539 		}
540 
541 		if (conn->conn_ops->DataDigest) {
542 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
543 						  data_buf, data_buf_len,
544 						  padding, &cmd->pad_bytes,
545 						  &cmd->data_crc);
546 
547 			iov[niov].iov_base = &cmd->data_crc;
548 			iov[niov++].iov_len = ISCSI_CRC_LEN;
549 			tx_size += ISCSI_CRC_LEN;
550 			pr_debug("Attached DataDigest for %u"
551 				 " bytes opcode 0x%x, CRC 0x%08x\n",
552 				 data_buf_len, hdr->opcode, cmd->data_crc);
553 		}
554 	}
555 
556 	cmd->iov_misc_count = niov;
557 	cmd->tx_size = tx_size;
558 
559 	ret = iscsit_send_tx_data(cmd, conn, 1);
560 	if (ret < 0) {
561 		iscsit_tx_thread_wait_for_tcp(conn);
562 		return ret;
563 	}
564 
565 	return 0;
566 }
567 
568 static int iscsit_map_iovec(struct iscsi_cmd *cmd, struct kvec *iov, int nvec,
569 			    u32 data_offset, u32 data_length);
570 static void iscsit_unmap_iovec(struct iscsi_cmd *);
571 static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsi_cmd *,
572 				    u32, u32, u32, u8 *);
573 static int
574 iscsit_xmit_datain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
575 		       const struct iscsi_datain *datain)
576 {
577 	struct kvec *iov;
578 	u32 iov_count = 0, tx_size = 0;
579 	int ret, iov_ret;
580 
581 	iov = &cmd->iov_data[0];
582 	iov[iov_count].iov_base	= cmd->pdu;
583 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
584 	tx_size += ISCSI_HDR_LEN;
585 
586 	if (conn->conn_ops->HeaderDigest) {
587 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
588 
589 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
590 					  ISCSI_HDR_LEN, 0, NULL,
591 					  header_digest);
592 
593 		iov[0].iov_len += ISCSI_CRC_LEN;
594 		tx_size += ISCSI_CRC_LEN;
595 
596 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
597 			 *header_digest);
598 	}
599 
600 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[iov_count],
601 				   cmd->orig_iov_data_count - (iov_count + 2),
602 				   datain->offset, datain->length);
603 	if (iov_ret < 0)
604 		return -1;
605 
606 	iov_count += iov_ret;
607 	tx_size += datain->length;
608 
609 	cmd->padding = ((-datain->length) & 3);
610 	if (cmd->padding) {
611 		iov[iov_count].iov_base		= cmd->pad_bytes;
612 		iov[iov_count++].iov_len	= cmd->padding;
613 		tx_size += cmd->padding;
614 
615 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
616 	}
617 
618 	if (conn->conn_ops->DataDigest) {
619 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
620 							 cmd, datain->offset,
621 							 datain->length,
622 							 cmd->padding,
623 							 cmd->pad_bytes);
624 
625 		iov[iov_count].iov_base	= &cmd->data_crc;
626 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
627 		tx_size += ISCSI_CRC_LEN;
628 
629 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
630 			 datain->length + cmd->padding, cmd->data_crc);
631 	}
632 
633 	cmd->iov_data_count = iov_count;
634 	cmd->tx_size = tx_size;
635 
636 	ret = iscsit_fe_sendpage_sg(cmd, conn);
637 
638 	iscsit_unmap_iovec(cmd);
639 
640 	if (ret < 0) {
641 		iscsit_tx_thread_wait_for_tcp(conn);
642 		return ret;
643 	}
644 
645 	return 0;
646 }
647 
648 static int iscsit_xmit_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
649 			   struct iscsi_datain_req *dr, const void *buf,
650 			   u32 buf_len)
651 {
652 	if (dr)
653 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
654 	else
655 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
656 }
657 
658 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
659 {
660 	return TARGET_PROT_NORMAL;
661 }
662 
663 static struct iscsit_transport iscsi_target_transport = {
664 	.name			= "iSCSI/TCP",
665 	.transport_type		= ISCSI_TCP,
666 	.rdma_shutdown		= false,
667 	.owner			= NULL,
668 	.iscsit_setup_np	= iscsit_setup_np,
669 	.iscsit_accept_np	= iscsit_accept_np,
670 	.iscsit_free_np		= iscsit_free_np,
671 	.iscsit_get_login_rx	= iscsit_get_login_rx,
672 	.iscsit_put_login_tx	= iscsit_put_login_tx,
673 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
674 	.iscsit_immediate_queue	= iscsit_immediate_queue,
675 	.iscsit_response_queue	= iscsit_response_queue,
676 	.iscsit_queue_data_in	= iscsit_queue_rsp,
677 	.iscsit_queue_status	= iscsit_queue_rsp,
678 	.iscsit_aborted_task	= iscsit_aborted_task,
679 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
680 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
681 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
682 };
683 
684 static int __init iscsi_target_init_module(void)
685 {
686 	int ret = 0, size;
687 
688 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
689 	iscsit_global = kzalloc(sizeof(*iscsit_global), GFP_KERNEL);
690 	if (!iscsit_global)
691 		return -1;
692 
693 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
694 	mutex_init(&auth_id_lock);
695 	idr_init(&tiqn_idr);
696 
697 	ret = target_register_template(&iscsi_ops);
698 	if (ret)
699 		goto out;
700 
701 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
702 	iscsit_global->ts_bitmap = vzalloc(size);
703 	if (!iscsit_global->ts_bitmap)
704 		goto configfs_out;
705 
706 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
707 			sizeof(struct iscsi_queue_req),
708 			__alignof__(struct iscsi_queue_req), 0, NULL);
709 	if (!lio_qr_cache) {
710 		pr_err("Unable to kmem_cache_create() for"
711 				" lio_qr_cache\n");
712 		goto bitmap_out;
713 	}
714 
715 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
716 			sizeof(struct iscsi_datain_req),
717 			__alignof__(struct iscsi_datain_req), 0, NULL);
718 	if (!lio_dr_cache) {
719 		pr_err("Unable to kmem_cache_create() for"
720 				" lio_dr_cache\n");
721 		goto qr_out;
722 	}
723 
724 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
725 			sizeof(struct iscsi_ooo_cmdsn),
726 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
727 	if (!lio_ooo_cache) {
728 		pr_err("Unable to kmem_cache_create() for"
729 				" lio_ooo_cache\n");
730 		goto dr_out;
731 	}
732 
733 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
734 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
735 			0, NULL);
736 	if (!lio_r2t_cache) {
737 		pr_err("Unable to kmem_cache_create() for"
738 				" lio_r2t_cache\n");
739 		goto ooo_out;
740 	}
741 
742 	iscsit_register_transport(&iscsi_target_transport);
743 
744 	if (iscsit_load_discovery_tpg() < 0)
745 		goto r2t_out;
746 
747 	return ret;
748 r2t_out:
749 	iscsit_unregister_transport(&iscsi_target_transport);
750 	kmem_cache_destroy(lio_r2t_cache);
751 ooo_out:
752 	kmem_cache_destroy(lio_ooo_cache);
753 dr_out:
754 	kmem_cache_destroy(lio_dr_cache);
755 qr_out:
756 	kmem_cache_destroy(lio_qr_cache);
757 bitmap_out:
758 	vfree(iscsit_global->ts_bitmap);
759 configfs_out:
760 	/* XXX: this probably wants it to be it's own unwind step.. */
761 	if (iscsit_global->discovery_tpg)
762 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
763 	target_unregister_template(&iscsi_ops);
764 out:
765 	kfree(iscsit_global);
766 	return -ENOMEM;
767 }
768 
769 static void __exit iscsi_target_cleanup_module(void)
770 {
771 	iscsit_release_discovery_tpg();
772 	iscsit_unregister_transport(&iscsi_target_transport);
773 	kmem_cache_destroy(lio_qr_cache);
774 	kmem_cache_destroy(lio_dr_cache);
775 	kmem_cache_destroy(lio_ooo_cache);
776 	kmem_cache_destroy(lio_r2t_cache);
777 
778 	/*
779 	 * Shutdown discovery sessions and disable discovery TPG
780 	 */
781 	if (iscsit_global->discovery_tpg)
782 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
783 
784 	target_unregister_template(&iscsi_ops);
785 
786 	vfree(iscsit_global->ts_bitmap);
787 	kfree(iscsit_global);
788 }
789 
790 int iscsit_add_reject(
791 	struct iscsi_conn *conn,
792 	u8 reason,
793 	unsigned char *buf)
794 {
795 	struct iscsi_cmd *cmd;
796 
797 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
798 	if (!cmd)
799 		return -1;
800 
801 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
802 	cmd->reject_reason = reason;
803 
804 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
805 	if (!cmd->buf_ptr) {
806 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
807 		iscsit_free_cmd(cmd, false);
808 		return -1;
809 	}
810 
811 	spin_lock_bh(&conn->cmd_lock);
812 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
813 	spin_unlock_bh(&conn->cmd_lock);
814 
815 	cmd->i_state = ISTATE_SEND_REJECT;
816 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
817 
818 	return -1;
819 }
820 EXPORT_SYMBOL(iscsit_add_reject);
821 
822 static int iscsit_add_reject_from_cmd(
823 	struct iscsi_cmd *cmd,
824 	u8 reason,
825 	bool add_to_conn,
826 	unsigned char *buf)
827 {
828 	struct iscsi_conn *conn;
829 	const bool do_put = cmd->se_cmd.se_tfo != NULL;
830 
831 	if (!cmd->conn) {
832 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
833 				cmd->init_task_tag);
834 		return -1;
835 	}
836 	conn = cmd->conn;
837 
838 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
839 	cmd->reject_reason = reason;
840 
841 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
842 	if (!cmd->buf_ptr) {
843 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
844 		iscsit_free_cmd(cmd, false);
845 		return -1;
846 	}
847 
848 	if (add_to_conn) {
849 		spin_lock_bh(&conn->cmd_lock);
850 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
851 		spin_unlock_bh(&conn->cmd_lock);
852 	}
853 
854 	cmd->i_state = ISTATE_SEND_REJECT;
855 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
856 	/*
857 	 * Perform the kref_put now if se_cmd has already been setup by
858 	 * scsit_setup_scsi_cmd()
859 	 */
860 	if (do_put) {
861 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
862 		target_put_sess_cmd(&cmd->se_cmd);
863 	}
864 	return -1;
865 }
866 
867 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
868 				 unsigned char *buf)
869 {
870 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
871 }
872 
873 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
874 {
875 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
876 }
877 EXPORT_SYMBOL(iscsit_reject_cmd);
878 
879 /*
880  * Map some portion of the allocated scatterlist to an iovec, suitable for
881  * kernel sockets to copy data in/out.
882  */
883 static int iscsit_map_iovec(struct iscsi_cmd *cmd, struct kvec *iov, int nvec,
884 			    u32 data_offset, u32 data_length)
885 {
886 	u32 i = 0, orig_data_length = data_length;
887 	struct scatterlist *sg;
888 	unsigned int page_off;
889 
890 	/*
891 	 * We know each entry in t_data_sg contains a page.
892 	 */
893 	u32 ent = data_offset / PAGE_SIZE;
894 
895 	if (!data_length)
896 		return 0;
897 
898 	if (ent >= cmd->se_cmd.t_data_nents) {
899 		pr_err("Initial page entry out-of-bounds\n");
900 		goto overflow;
901 	}
902 
903 	sg = &cmd->se_cmd.t_data_sg[ent];
904 	page_off = (data_offset % PAGE_SIZE);
905 
906 	cmd->first_data_sg = sg;
907 	cmd->first_data_sg_off = page_off;
908 
909 	while (data_length) {
910 		u32 cur_len;
911 
912 		if (WARN_ON_ONCE(!sg || i >= nvec))
913 			goto overflow;
914 
915 		cur_len = min_t(u32, data_length, sg->length - page_off);
916 
917 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
918 		iov[i].iov_len = cur_len;
919 
920 		data_length -= cur_len;
921 		page_off = 0;
922 		sg = sg_next(sg);
923 		i++;
924 	}
925 
926 	cmd->kmapped_nents = i;
927 
928 	return i;
929 
930 overflow:
931 	pr_err("offset %d + length %d overflow; %d/%d; sg-list:\n",
932 	       data_offset, orig_data_length, i, nvec);
933 	for_each_sg(cmd->se_cmd.t_data_sg, sg,
934 		    cmd->se_cmd.t_data_nents, i) {
935 		pr_err("[%d] off %d len %d\n",
936 		       i, sg->offset, sg->length);
937 	}
938 	return -1;
939 }
940 
941 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
942 {
943 	u32 i;
944 	struct scatterlist *sg;
945 
946 	sg = cmd->first_data_sg;
947 
948 	for (i = 0; i < cmd->kmapped_nents; i++)
949 		kunmap(sg_page(&sg[i]));
950 }
951 
952 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
953 {
954 	LIST_HEAD(ack_list);
955 	struct iscsi_cmd *cmd, *cmd_p;
956 
957 	conn->exp_statsn = exp_statsn;
958 
959 	if (conn->sess->sess_ops->RDMAExtensions)
960 		return;
961 
962 	spin_lock_bh(&conn->cmd_lock);
963 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
964 		spin_lock(&cmd->istate_lock);
965 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
966 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
967 			cmd->i_state = ISTATE_REMOVE;
968 			spin_unlock(&cmd->istate_lock);
969 			list_move_tail(&cmd->i_conn_node, &ack_list);
970 			continue;
971 		}
972 		spin_unlock(&cmd->istate_lock);
973 	}
974 	spin_unlock_bh(&conn->cmd_lock);
975 
976 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
977 		list_del_init(&cmd->i_conn_node);
978 		iscsit_free_cmd(cmd, false);
979 	}
980 }
981 
982 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
983 {
984 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
985 
986 	iov_count += ISCSI_IOV_DATA_BUFFER;
987 	cmd->iov_data = kcalloc(iov_count, sizeof(*cmd->iov_data), GFP_KERNEL);
988 	if (!cmd->iov_data)
989 		return -ENOMEM;
990 
991 	cmd->orig_iov_data_count = iov_count;
992 	return 0;
993 }
994 
995 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
996 			  unsigned char *buf)
997 {
998 	int data_direction, payload_length;
999 	struct iscsi_scsi_req *hdr;
1000 	int iscsi_task_attr;
1001 	int sam_task_attr;
1002 
1003 	atomic_long_inc(&conn->sess->cmd_pdus);
1004 
1005 	hdr			= (struct iscsi_scsi_req *) buf;
1006 	payload_length		= ntoh24(hdr->dlength);
1007 
1008 	/* FIXME; Add checks for AdditionalHeaderSegment */
1009 
1010 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1011 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1012 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1013 				" not set. Bad iSCSI Initiator.\n");
1014 		return iscsit_add_reject_cmd(cmd,
1015 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1016 	}
1017 
1018 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1019 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1020 		/*
1021 		 * From RFC-3720 Section 10.3.1:
1022 		 *
1023 		 * "Either or both of R and W MAY be 1 when either the
1024 		 *  Expected Data Transfer Length and/or Bidirectional Read
1025 		 *  Expected Data Transfer Length are 0"
1026 		 *
1027 		 * For this case, go ahead and clear the unnecssary bits
1028 		 * to avoid any confusion with ->data_direction.
1029 		 */
1030 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1031 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1032 
1033 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1034 			" set when Expected Data Transfer Length is 0 for"
1035 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1036 	}
1037 
1038 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1039 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1040 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1041 			" MUST be set if Expected Data Transfer Length is not 0."
1042 			" Bad iSCSI Initiator\n");
1043 		return iscsit_add_reject_cmd(cmd,
1044 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1045 	}
1046 
1047 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1048 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1049 		pr_err("Bidirectional operations not supported!\n");
1050 		return iscsit_add_reject_cmd(cmd,
1051 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1052 	}
1053 
1054 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1055 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1056 				" Scsi Command PDU.\n");
1057 		return iscsit_add_reject_cmd(cmd,
1058 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1059 	}
1060 
1061 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1062 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1063 			" protocol error.\n", payload_length);
1064 		return iscsit_add_reject_cmd(cmd,
1065 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1066 	}
1067 
1068 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1069 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1070 		pr_err("Expected Data Transfer Length and Length of"
1071 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1072 			" bit is not set protocol error\n");
1073 		return iscsit_add_reject_cmd(cmd,
1074 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1075 	}
1076 
1077 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1078 		pr_err("DataSegmentLength: %u is greater than"
1079 			" EDTL: %u, protocol error.\n", payload_length,
1080 				hdr->data_length);
1081 		return iscsit_add_reject_cmd(cmd,
1082 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1083 	}
1084 
1085 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1086 		pr_err("DataSegmentLength: %u is greater than"
1087 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1088 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1089 		return iscsit_add_reject_cmd(cmd,
1090 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1091 	}
1092 
1093 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1094 		pr_err("DataSegmentLength: %u is greater than"
1095 			" FirstBurstLength: %u, protocol error.\n",
1096 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1097 		return iscsit_add_reject_cmd(cmd,
1098 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1099 	}
1100 
1101 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1102 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1103 			  DMA_NONE;
1104 
1105 	cmd->data_direction = data_direction;
1106 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1107 	/*
1108 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1109 	 */
1110 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1111 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1112 		sam_task_attr = TCM_SIMPLE_TAG;
1113 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1114 		sam_task_attr = TCM_ORDERED_TAG;
1115 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1116 		sam_task_attr = TCM_HEAD_TAG;
1117 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1118 		sam_task_attr = TCM_ACA_TAG;
1119 	else {
1120 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1121 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1122 		sam_task_attr = TCM_SIMPLE_TAG;
1123 	}
1124 
1125 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1126 	cmd->i_state		= ISTATE_NEW_CMD;
1127 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1128 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1129 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1130 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1131 	if (cmd->unsolicited_data)
1132 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1133 
1134 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1135 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1136 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1137 	else
1138 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1139 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1140 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1141 	cmd->first_burst_len	= payload_length;
1142 
1143 	if (!conn->sess->sess_ops->RDMAExtensions &&
1144 	     cmd->data_direction == DMA_FROM_DEVICE) {
1145 		struct iscsi_datain_req *dr;
1146 
1147 		dr = iscsit_allocate_datain_req();
1148 		if (!dr)
1149 			return iscsit_add_reject_cmd(cmd,
1150 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1151 
1152 		iscsit_attach_datain_req(cmd, dr);
1153 	}
1154 
1155 	/*
1156 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1157 	 */
1158 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1159 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1160 			cmd->data_direction, sam_task_attr,
1161 			cmd->sense_buffer + 2);
1162 
1163 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1164 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1165 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1166 		conn->cid);
1167 
1168 	target_get_sess_cmd(&cmd->se_cmd, true);
1169 
1170 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
1171 						     scsilun_to_int(&hdr->lun));
1172 	if (cmd->sense_reason)
1173 		goto attach_cmd;
1174 
1175 	/* only used for printks or comparing with ->ref_task_tag */
1176 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1177 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
1178 	if (cmd->sense_reason) {
1179 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1180 			return iscsit_add_reject_cmd(cmd,
1181 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1182 		}
1183 
1184 		goto attach_cmd;
1185 	}
1186 
1187 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1188 		return iscsit_add_reject_cmd(cmd,
1189 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1190 	}
1191 
1192 attach_cmd:
1193 	spin_lock_bh(&conn->cmd_lock);
1194 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1195 	spin_unlock_bh(&conn->cmd_lock);
1196 	/*
1197 	 * Check if we need to delay processing because of ALUA
1198 	 * Active/NonOptimized primary access state..
1199 	 */
1200 	core_alua_check_nonop_delay(&cmd->se_cmd);
1201 
1202 	return 0;
1203 }
1204 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1205 
1206 void iscsit_set_unsolicited_dataout(struct iscsi_cmd *cmd)
1207 {
1208 	iscsit_set_dataout_sequence_values(cmd);
1209 
1210 	spin_lock_bh(&cmd->dataout_timeout_lock);
1211 	iscsit_start_dataout_timer(cmd, cmd->conn);
1212 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1213 }
1214 EXPORT_SYMBOL(iscsit_set_unsolicited_dataout);
1215 
1216 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1217 			    struct iscsi_scsi_req *hdr)
1218 {
1219 	int cmdsn_ret = 0;
1220 	/*
1221 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1222 	 * the Immediate Bit is not set, and no Immediate
1223 	 * Data is attached.
1224 	 *
1225 	 * A PDU/CmdSN carrying Immediate Data can only
1226 	 * be processed after the DataCRC has passed.
1227 	 * If the DataCRC fails, the CmdSN MUST NOT
1228 	 * be acknowledged. (See below)
1229 	 */
1230 	if (!cmd->immediate_data) {
1231 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1232 					(unsigned char *)hdr, hdr->cmdsn);
1233 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1234 			return -1;
1235 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1236 			target_put_sess_cmd(&cmd->se_cmd);
1237 			return 0;
1238 		}
1239 	}
1240 
1241 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1242 
1243 	/*
1244 	 * If no Immediate Data is attached, it's OK to return now.
1245 	 */
1246 	if (!cmd->immediate_data) {
1247 		if (!cmd->sense_reason && cmd->unsolicited_data)
1248 			iscsit_set_unsolicited_dataout(cmd);
1249 		if (!cmd->sense_reason)
1250 			return 0;
1251 
1252 		target_put_sess_cmd(&cmd->se_cmd);
1253 		return 0;
1254 	}
1255 
1256 	/*
1257 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1258 	 * execution.  These exceptions are processed in CmdSN order using
1259 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1260 	 */
1261 	if (cmd->sense_reason)
1262 		return 1;
1263 	/*
1264 	 * Call directly into transport_generic_new_cmd() to perform
1265 	 * the backend memory allocation.
1266 	 */
1267 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1268 	if (cmd->sense_reason)
1269 		return 1;
1270 
1271 	return 0;
1272 }
1273 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1274 
1275 static int
1276 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1277 			  bool dump_payload)
1278 {
1279 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1280 	int rc;
1281 
1282 	/*
1283 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1284 	 */
1285 	if (dump_payload) {
1286 		u32 length = min(cmd->se_cmd.data_length - cmd->write_data_done,
1287 				 cmd->first_burst_len);
1288 
1289 		pr_debug("Dumping min(%d - %d, %d) = %d bytes of immediate data\n",
1290 			 cmd->se_cmd.data_length, cmd->write_data_done,
1291 			 cmd->first_burst_len, length);
1292 		rc = iscsit_dump_data_payload(cmd->conn, length, 1);
1293 		pr_debug("Finished dumping immediate data\n");
1294 		if (rc < 0)
1295 			immed_ret = IMMEDIATE_DATA_CANNOT_RECOVER;
1296 	} else {
1297 		immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1298 							 cmd->first_burst_len);
1299 	}
1300 
1301 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1302 		/*
1303 		 * A PDU/CmdSN carrying Immediate Data passed
1304 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1305 		 * Immediate Bit is not set.
1306 		 */
1307 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1308 					(unsigned char *)hdr, hdr->cmdsn);
1309 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1310 			return -1;
1311 
1312 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1313 			target_put_sess_cmd(&cmd->se_cmd);
1314 
1315 			return 0;
1316 		} else if (cmd->unsolicited_data)
1317 			iscsit_set_unsolicited_dataout(cmd);
1318 
1319 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1320 		/*
1321 		 * Immediate Data failed DataCRC and ERL>=1,
1322 		 * silently drop this PDU and let the initiator
1323 		 * plug the CmdSN gap.
1324 		 *
1325 		 * FIXME: Send Unsolicited NOPIN with reserved
1326 		 * TTT here to help the initiator figure out
1327 		 * the missing CmdSN, although they should be
1328 		 * intelligent enough to determine the missing
1329 		 * CmdSN and issue a retry to plug the sequence.
1330 		 */
1331 		cmd->i_state = ISTATE_REMOVE;
1332 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1333 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1334 		return -1;
1335 
1336 	return 0;
1337 }
1338 
1339 static int
1340 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1341 			   unsigned char *buf)
1342 {
1343 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1344 	int rc, immed_data;
1345 	bool dump_payload = false;
1346 
1347 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1348 	if (rc < 0)
1349 		return 0;
1350 	/*
1351 	 * Allocation iovecs needed for struct socket operations for
1352 	 * traditional iSCSI block I/O.
1353 	 */
1354 	if (iscsit_allocate_iovecs(cmd) < 0) {
1355 		return iscsit_reject_cmd(cmd,
1356 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1357 	}
1358 	immed_data = cmd->immediate_data;
1359 
1360 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1361 	if (rc < 0)
1362 		return rc;
1363 	else if (rc > 0)
1364 		dump_payload = true;
1365 
1366 	if (!immed_data)
1367 		return 0;
1368 
1369 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1370 }
1371 
1372 static u32 iscsit_do_crypto_hash_sg(
1373 	struct ahash_request *hash,
1374 	struct iscsi_cmd *cmd,
1375 	u32 data_offset,
1376 	u32 data_length,
1377 	u32 padding,
1378 	u8 *pad_bytes)
1379 {
1380 	u32 data_crc;
1381 	struct scatterlist *sg;
1382 	unsigned int page_off;
1383 
1384 	crypto_ahash_init(hash);
1385 
1386 	sg = cmd->first_data_sg;
1387 	page_off = cmd->first_data_sg_off;
1388 
1389 	while (data_length) {
1390 		u32 cur_len = min_t(u32, data_length, (sg->length - page_off));
1391 
1392 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1393 		crypto_ahash_update(hash);
1394 
1395 		data_length -= cur_len;
1396 		page_off = 0;
1397 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1398 		sg = sg_next(sg);
1399 	}
1400 
1401 	if (padding) {
1402 		struct scatterlist pad_sg;
1403 
1404 		sg_init_one(&pad_sg, pad_bytes, padding);
1405 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1406 					padding);
1407 		crypto_ahash_finup(hash);
1408 	} else {
1409 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1410 		crypto_ahash_final(hash);
1411 	}
1412 
1413 	return data_crc;
1414 }
1415 
1416 static void iscsit_do_crypto_hash_buf(struct ahash_request *hash,
1417 	const void *buf, u32 payload_length, u32 padding,
1418 	const void *pad_bytes, void *data_crc)
1419 {
1420 	struct scatterlist sg[2];
1421 
1422 	sg_init_table(sg, ARRAY_SIZE(sg));
1423 	sg_set_buf(sg, buf, payload_length);
1424 	if (padding)
1425 		sg_set_buf(sg + 1, pad_bytes, padding);
1426 
1427 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1428 
1429 	crypto_ahash_digest(hash);
1430 }
1431 
1432 int
1433 __iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1434 			   struct iscsi_cmd *cmd, u32 payload_length,
1435 			   bool *success)
1436 {
1437 	struct iscsi_data *hdr = buf;
1438 	struct se_cmd *se_cmd;
1439 	int rc;
1440 
1441 	/* iSCSI write */
1442 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1443 
1444 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1445 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1446 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1447 		payload_length, conn->cid);
1448 
1449 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1450 		pr_err("Command ITT: 0x%08x received DataOUT after"
1451 			" last DataOUT received, dumping payload\n",
1452 			cmd->init_task_tag);
1453 		return iscsit_dump_data_payload(conn, payload_length, 1);
1454 	}
1455 
1456 	if (cmd->data_direction != DMA_TO_DEVICE) {
1457 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1458 			" NON-WRITE command.\n", cmd->init_task_tag);
1459 		return iscsit_dump_data_payload(conn, payload_length, 1);
1460 	}
1461 	se_cmd = &cmd->se_cmd;
1462 	iscsit_mod_dataout_timer(cmd);
1463 
1464 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1465 		pr_err("DataOut Offset: %u, Length %u greater than iSCSI Command EDTL %u, protocol error.\n",
1466 		       be32_to_cpu(hdr->offset), payload_length,
1467 		       cmd->se_cmd.data_length);
1468 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1469 	}
1470 
1471 	if (cmd->unsolicited_data) {
1472 		int dump_unsolicited_data = 0;
1473 
1474 		if (conn->sess->sess_ops->InitialR2T) {
1475 			pr_err("Received unexpected unsolicited data"
1476 				" while InitialR2T=Yes, protocol error.\n");
1477 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1478 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1479 			return -1;
1480 		}
1481 		/*
1482 		 * Special case for dealing with Unsolicited DataOUT
1483 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1484 		 * failures;
1485 		 */
1486 
1487 		/* Something's amiss if we're not in WRITE_PENDING state... */
1488 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1489 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1490 			dump_unsolicited_data = 1;
1491 
1492 		if (dump_unsolicited_data) {
1493 			/*
1494 			 * Check if a delayed TASK_ABORTED status needs to
1495 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1496 			 * received with the unsolicited data out.
1497 			 */
1498 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1499 				iscsit_stop_dataout_timer(cmd);
1500 
1501 			return iscsit_dump_data_payload(conn, payload_length, 1);
1502 		}
1503 	} else {
1504 		/*
1505 		 * For the normal solicited data path:
1506 		 *
1507 		 * Check for a delayed TASK_ABORTED status and dump any
1508 		 * incoming data out payload if one exists.  Also, when the
1509 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1510 		 * data out sequence, we decrement outstanding_r2ts.  Once
1511 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1512 		 * TASK_ABORTED status.
1513 		 */
1514 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1515 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL &&
1516 			    --cmd->outstanding_r2ts < 1)
1517 				iscsit_stop_dataout_timer(cmd);
1518 
1519 			return iscsit_dump_data_payload(conn, payload_length, 1);
1520 		}
1521 	}
1522 	/*
1523 	 * Perform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1524 	 * within-command recovery checks before receiving the payload.
1525 	 */
1526 	rc = iscsit_check_pre_dataout(cmd, buf);
1527 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1528 		return 0;
1529 	else if (rc == DATAOUT_CANNOT_RECOVER)
1530 		return -1;
1531 	*success = true;
1532 	return 0;
1533 }
1534 EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
1535 
1536 int
1537 iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1538 			 struct iscsi_cmd **out_cmd)
1539 {
1540 	struct iscsi_data *hdr = buf;
1541 	struct iscsi_cmd *cmd;
1542 	u32 payload_length = ntoh24(hdr->dlength);
1543 	int rc;
1544 	bool success = false;
1545 
1546 	if (!payload_length) {
1547 		pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
1548 		return 0;
1549 	}
1550 
1551 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1552 		pr_err_ratelimited("DataSegmentLength: %u is greater than"
1553 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1554 			conn->conn_ops->MaxXmitDataSegmentLength);
1555 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
1556 	}
1557 
1558 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
1559 	if (!cmd)
1560 		return 0;
1561 
1562 	rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
1563 
1564 	if (success)
1565 		*out_cmd = cmd;
1566 
1567 	return rc;
1568 }
1569 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1570 
1571 static int
1572 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1573 		   struct iscsi_data *hdr)
1574 {
1575 	struct kvec *iov;
1576 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1577 	u32 payload_length;
1578 	int iov_ret, data_crc_failed = 0;
1579 
1580 	payload_length = min_t(u32, cmd->se_cmd.data_length,
1581 			       ntoh24(hdr->dlength));
1582 	rx_size += payload_length;
1583 	iov = &cmd->iov_data[0];
1584 
1585 	iov_ret = iscsit_map_iovec(cmd, iov, cmd->orig_iov_data_count - 2,
1586 				   be32_to_cpu(hdr->offset), payload_length);
1587 	if (iov_ret < 0)
1588 		return -1;
1589 
1590 	iov_count += iov_ret;
1591 
1592 	padding = ((-payload_length) & 3);
1593 	if (padding != 0) {
1594 		iov[iov_count].iov_base	= cmd->pad_bytes;
1595 		iov[iov_count++].iov_len = padding;
1596 		rx_size += padding;
1597 		pr_debug("Receiving %u padding bytes.\n", padding);
1598 	}
1599 
1600 	if (conn->conn_ops->DataDigest) {
1601 		iov[iov_count].iov_base = &checksum;
1602 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1603 		rx_size += ISCSI_CRC_LEN;
1604 	}
1605 
1606 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
1607 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1608 
1609 	iscsit_unmap_iovec(cmd);
1610 
1611 	if (rx_got != rx_size)
1612 		return -1;
1613 
1614 	if (conn->conn_ops->DataDigest) {
1615 		u32 data_crc;
1616 
1617 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1618 						    be32_to_cpu(hdr->offset),
1619 						    payload_length, padding,
1620 						    cmd->pad_bytes);
1621 
1622 		if (checksum != data_crc) {
1623 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1624 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1625 				" does not match computed 0x%08x\n",
1626 				hdr->itt, hdr->offset, payload_length,
1627 				hdr->datasn, checksum, data_crc);
1628 			data_crc_failed = 1;
1629 		} else {
1630 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1631 				" %u bytes of Data Out\n", checksum,
1632 				payload_length);
1633 		}
1634 	}
1635 
1636 	return data_crc_failed;
1637 }
1638 
1639 int
1640 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1641 			     bool data_crc_failed)
1642 {
1643 	struct iscsi_conn *conn = cmd->conn;
1644 	int rc, ooo_cmdsn;
1645 	/*
1646 	 * Increment post receive data and CRC values or perform
1647 	 * within-command recovery.
1648 	 */
1649 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1650 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1651 		return 0;
1652 	else if (rc == DATAOUT_SEND_R2T) {
1653 		iscsit_set_dataout_sequence_values(cmd);
1654 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1655 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1656 		/*
1657 		 * Handle extra special case for out of order
1658 		 * Unsolicited Data Out.
1659 		 */
1660 		spin_lock_bh(&cmd->istate_lock);
1661 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1662 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1663 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1664 		spin_unlock_bh(&cmd->istate_lock);
1665 
1666 		iscsit_stop_dataout_timer(cmd);
1667 		if (ooo_cmdsn)
1668 			return 0;
1669 		target_execute_cmd(&cmd->se_cmd);
1670 		return 0;
1671 	} else /* DATAOUT_CANNOT_RECOVER */
1672 		return -1;
1673 
1674 	return 0;
1675 }
1676 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1677 
1678 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1679 {
1680 	struct iscsi_cmd *cmd = NULL;
1681 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1682 	int rc;
1683 	bool data_crc_failed = false;
1684 
1685 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1686 	if (rc < 0)
1687 		return 0;
1688 	else if (!cmd)
1689 		return 0;
1690 
1691 	rc = iscsit_get_dataout(conn, cmd, hdr);
1692 	if (rc < 0)
1693 		return rc;
1694 	else if (rc > 0)
1695 		data_crc_failed = true;
1696 
1697 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1698 }
1699 
1700 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1701 			 struct iscsi_nopout *hdr)
1702 {
1703 	u32 payload_length = ntoh24(hdr->dlength);
1704 
1705 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1706 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1707 		if (!cmd)
1708 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1709 						 (unsigned char *)hdr);
1710 
1711 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1712 					 (unsigned char *)hdr);
1713 	}
1714 
1715 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1716 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1717 			" not set, protocol error.\n");
1718 		if (!cmd)
1719 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1720 						 (unsigned char *)hdr);
1721 
1722 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1723 					 (unsigned char *)hdr);
1724 	}
1725 
1726 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1727 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1728 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1729 			" error.\n", payload_length,
1730 			conn->conn_ops->MaxXmitDataSegmentLength);
1731 		if (!cmd)
1732 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1733 						 (unsigned char *)hdr);
1734 
1735 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1736 					 (unsigned char *)hdr);
1737 	}
1738 
1739 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1740 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1741 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1742 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1743 		payload_length);
1744 	/*
1745 	 * This is not a response to a Unsolicited NopIN, which means
1746 	 * it can either be a NOPOUT ping request (with a valid ITT),
1747 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1748 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1749 	 * can contain ping data.
1750 	 */
1751 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1752 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1753 		cmd->i_state		= ISTATE_SEND_NOPIN;
1754 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1755 						1 : 0);
1756 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1757 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1758 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1759 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1760 		cmd->data_direction	= DMA_NONE;
1761 	}
1762 
1763 	return 0;
1764 }
1765 EXPORT_SYMBOL(iscsit_setup_nop_out);
1766 
1767 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1768 			   struct iscsi_nopout *hdr)
1769 {
1770 	struct iscsi_cmd *cmd_p = NULL;
1771 	int cmdsn_ret = 0;
1772 	/*
1773 	 * Initiator is expecting a NopIN ping reply..
1774 	 */
1775 	if (hdr->itt != RESERVED_ITT) {
1776 		if (!cmd)
1777 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1778 						(unsigned char *)hdr);
1779 
1780 		spin_lock_bh(&conn->cmd_lock);
1781 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1782 		spin_unlock_bh(&conn->cmd_lock);
1783 
1784 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1785 
1786 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1787 			iscsit_add_cmd_to_response_queue(cmd, conn,
1788 							 cmd->i_state);
1789 			return 0;
1790 		}
1791 
1792 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1793 				(unsigned char *)hdr, hdr->cmdsn);
1794                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1795 			return 0;
1796 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1797 			return -1;
1798 
1799 		return 0;
1800 	}
1801 	/*
1802 	 * This was a response to a unsolicited NOPIN ping.
1803 	 */
1804 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1805 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1806 		if (!cmd_p)
1807 			return -EINVAL;
1808 
1809 		iscsit_stop_nopin_response_timer(conn);
1810 
1811 		cmd_p->i_state = ISTATE_REMOVE;
1812 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1813 
1814 		iscsit_start_nopin_timer(conn);
1815 		return 0;
1816 	}
1817 	/*
1818 	 * Otherwise, initiator is not expecting a NOPIN is response.
1819 	 * Just ignore for now.
1820 	 */
1821 
1822 	if (cmd)
1823 		iscsit_free_cmd(cmd, false);
1824 
1825         return 0;
1826 }
1827 EXPORT_SYMBOL(iscsit_process_nop_out);
1828 
1829 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1830 				 unsigned char *buf)
1831 {
1832 	unsigned char *ping_data = NULL;
1833 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1834 	struct kvec *iov = NULL;
1835 	u32 payload_length = ntoh24(hdr->dlength);
1836 	int ret;
1837 
1838 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1839 	if (ret < 0)
1840 		return 0;
1841 	/*
1842 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1843 	 */
1844 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1845 		u32 checksum, data_crc, padding = 0;
1846 		int niov = 0, rx_got, rx_size = payload_length;
1847 
1848 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1849 		if (!ping_data) {
1850 			ret = -1;
1851 			goto out;
1852 		}
1853 
1854 		iov = &cmd->iov_misc[0];
1855 		iov[niov].iov_base	= ping_data;
1856 		iov[niov++].iov_len	= payload_length;
1857 
1858 		padding = ((-payload_length) & 3);
1859 		if (padding != 0) {
1860 			pr_debug("Receiving %u additional bytes"
1861 				" for padding.\n", padding);
1862 			iov[niov].iov_base	= &cmd->pad_bytes;
1863 			iov[niov++].iov_len	= padding;
1864 			rx_size += padding;
1865 		}
1866 		if (conn->conn_ops->DataDigest) {
1867 			iov[niov].iov_base	= &checksum;
1868 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1869 			rx_size += ISCSI_CRC_LEN;
1870 		}
1871 
1872 		WARN_ON_ONCE(niov > ARRAY_SIZE(cmd->iov_misc));
1873 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1874 		if (rx_got != rx_size) {
1875 			ret = -1;
1876 			goto out;
1877 		}
1878 
1879 		if (conn->conn_ops->DataDigest) {
1880 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, ping_data,
1881 						  payload_length, padding,
1882 						  cmd->pad_bytes, &data_crc);
1883 
1884 			if (checksum != data_crc) {
1885 				pr_err("Ping data CRC32C DataDigest"
1886 				" 0x%08x does not match computed 0x%08x\n",
1887 					checksum, data_crc);
1888 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1889 					pr_err("Unable to recover from"
1890 					" NOPOUT Ping DataCRC failure while in"
1891 						" ERL=0.\n");
1892 					ret = -1;
1893 					goto out;
1894 				} else {
1895 					/*
1896 					 * Silently drop this PDU and let the
1897 					 * initiator plug the CmdSN gap.
1898 					 */
1899 					pr_debug("Dropping NOPOUT"
1900 					" Command CmdSN: 0x%08x due to"
1901 					" DataCRC error.\n", hdr->cmdsn);
1902 					ret = 0;
1903 					goto out;
1904 				}
1905 			} else {
1906 				pr_debug("Got CRC32C DataDigest"
1907 				" 0x%08x for %u bytes of ping data.\n",
1908 					checksum, payload_length);
1909 			}
1910 		}
1911 
1912 		ping_data[payload_length] = '\0';
1913 		/*
1914 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1915 		 */
1916 		cmd->buf_ptr = ping_data;
1917 		cmd->buf_ptr_size = payload_length;
1918 
1919 		pr_debug("Got %u bytes of NOPOUT ping"
1920 			" data.\n", payload_length);
1921 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1922 	}
1923 
1924 	return iscsit_process_nop_out(conn, cmd, hdr);
1925 out:
1926 	if (cmd)
1927 		iscsit_free_cmd(cmd, false);
1928 
1929 	kfree(ping_data);
1930 	return ret;
1931 }
1932 
1933 static enum tcm_tmreq_table iscsit_convert_tmf(u8 iscsi_tmf)
1934 {
1935 	switch (iscsi_tmf) {
1936 	case ISCSI_TM_FUNC_ABORT_TASK:
1937 		return TMR_ABORT_TASK;
1938 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1939 		return TMR_ABORT_TASK_SET;
1940 	case ISCSI_TM_FUNC_CLEAR_ACA:
1941 		return TMR_CLEAR_ACA;
1942 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1943 		return TMR_CLEAR_TASK_SET;
1944 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1945 		return TMR_LUN_RESET;
1946 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1947 		return TMR_TARGET_WARM_RESET;
1948 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1949 		return TMR_TARGET_COLD_RESET;
1950 	default:
1951 		return TMR_UNKNOWN;
1952 	}
1953 }
1954 
1955 int
1956 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1957 			   unsigned char *buf)
1958 {
1959 	struct se_tmr_req *se_tmr;
1960 	struct iscsi_tmr_req *tmr_req;
1961 	struct iscsi_tm *hdr;
1962 	int out_of_order_cmdsn = 0, ret;
1963 	u8 function, tcm_function = TMR_UNKNOWN;
1964 
1965 	hdr			= (struct iscsi_tm *) buf;
1966 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1967 	function = hdr->flags;
1968 
1969 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1970 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1971 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1972 		hdr->rtt, hdr->refcmdsn, conn->cid);
1973 
1974 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1975 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1976 	     hdr->rtt != RESERVED_ITT)) {
1977 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1978 		hdr->rtt = RESERVED_ITT;
1979 	}
1980 
1981 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1982 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1983 		pr_err("Task Management Request TASK_REASSIGN not"
1984 			" issued as immediate command, bad iSCSI Initiator"
1985 				"implementation\n");
1986 		return iscsit_add_reject_cmd(cmd,
1987 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1988 	}
1989 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1990 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1991 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1992 
1993 	cmd->data_direction = DMA_NONE;
1994 	cmd->tmr_req = kzalloc(sizeof(*cmd->tmr_req), GFP_KERNEL);
1995 	if (!cmd->tmr_req) {
1996 		return iscsit_add_reject_cmd(cmd,
1997 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1998 					     buf);
1999 	}
2000 
2001 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
2002 			      conn->sess->se_sess, 0, DMA_NONE,
2003 			      TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
2004 
2005 	target_get_sess_cmd(&cmd->se_cmd, true);
2006 
2007 	/*
2008 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
2009 	 * LIO-Target $FABRIC_MOD
2010 	 */
2011 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2012 		tcm_function = iscsit_convert_tmf(function);
2013 		if (tcm_function == TMR_UNKNOWN) {
2014 			pr_err("Unknown iSCSI TMR Function:"
2015 			       " 0x%02x\n", function);
2016 			return iscsit_add_reject_cmd(cmd,
2017 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2018 		}
2019 	}
2020 	ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
2021 				 GFP_KERNEL);
2022 	if (ret < 0)
2023 		return iscsit_add_reject_cmd(cmd,
2024 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2025 
2026 	cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2027 
2028 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2029 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2030 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2031 	cmd->init_task_tag	= hdr->itt;
2032 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2033 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2034 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2035 	se_tmr			= cmd->se_cmd.se_tmr_req;
2036 	tmr_req			= cmd->tmr_req;
2037 	/*
2038 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2039 	 */
2040 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2041 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
2042 					       scsilun_to_int(&hdr->lun));
2043 		if (ret < 0) {
2044 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2045 			goto attach;
2046 		}
2047 	}
2048 
2049 	switch (function) {
2050 	case ISCSI_TM_FUNC_ABORT_TASK:
2051 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2052 		if (se_tmr->response)
2053 			goto attach;
2054 		break;
2055 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2056 	case ISCSI_TM_FUNC_CLEAR_ACA:
2057 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2058 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2059 		break;
2060 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2061 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2062 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2063 			goto attach;
2064 		}
2065 		break;
2066 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2067 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2068 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2069 			goto attach;
2070 		}
2071 		break;
2072 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2073 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2074 		/*
2075 		 * Perform sanity checks on the ExpDataSN only if the
2076 		 * TASK_REASSIGN was successful.
2077 		 */
2078 		if (se_tmr->response)
2079 			break;
2080 
2081 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2082 			return iscsit_add_reject_cmd(cmd,
2083 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2084 		break;
2085 	default:
2086 		pr_err("Unknown TMR function: 0x%02x, protocol"
2087 			" error.\n", function);
2088 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2089 		goto attach;
2090 	}
2091 
2092 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2093 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2094 		se_tmr->call_transport = 1;
2095 attach:
2096 	spin_lock_bh(&conn->cmd_lock);
2097 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2098 	spin_unlock_bh(&conn->cmd_lock);
2099 
2100 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2101 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2102 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP) {
2103 			out_of_order_cmdsn = 1;
2104 		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2105 			target_put_sess_cmd(&cmd->se_cmd);
2106 			return 0;
2107 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2108 			return -1;
2109 		}
2110 	}
2111 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2112 
2113 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2114 		return 0;
2115 	/*
2116 	 * Found the referenced task, send to transport for processing.
2117 	 */
2118 	if (se_tmr->call_transport)
2119 		return transport_generic_handle_tmr(&cmd->se_cmd);
2120 
2121 	/*
2122 	 * Could not find the referenced LUN, task, or Task Management
2123 	 * command not authorized or supported.  Change state and
2124 	 * let the tx_thread send the response.
2125 	 *
2126 	 * For connection recovery, this is also the default action for
2127 	 * TMR TASK_REASSIGN.
2128 	 */
2129 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2130 	target_put_sess_cmd(&cmd->se_cmd);
2131 	return 0;
2132 }
2133 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2134 
2135 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2136 int
2137 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2138 		      struct iscsi_text *hdr)
2139 {
2140 	u32 payload_length = ntoh24(hdr->dlength);
2141 
2142 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2143 		pr_err("Unable to accept text parameter length: %u"
2144 			"greater than MaxXmitDataSegmentLength %u.\n",
2145 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2146 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2147 					 (unsigned char *)hdr);
2148 	}
2149 
2150 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2151 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2152 		pr_err("Multi sequence text commands currently not supported\n");
2153 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2154 					(unsigned char *)hdr);
2155 	}
2156 
2157 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2158 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2159 		hdr->exp_statsn, payload_length);
2160 
2161 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2162 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2163 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2164 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2165 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2166 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2167 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2168 	cmd->data_direction	= DMA_NONE;
2169 	kfree(cmd->text_in_ptr);
2170 	cmd->text_in_ptr	= NULL;
2171 
2172 	return 0;
2173 }
2174 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2175 
2176 int
2177 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2178 			struct iscsi_text *hdr)
2179 {
2180 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2181 	int cmdsn_ret;
2182 
2183 	if (!text_in) {
2184 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2185 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2186 			pr_err("Unable to locate text_in buffer for sendtargets"
2187 			       " discovery\n");
2188 			goto reject;
2189 		}
2190 		goto empty_sendtargets;
2191 	}
2192 	if (strncmp("SendTargets", text_in, 11) != 0) {
2193 		pr_err("Received Text Data that is not"
2194 			" SendTargets, cannot continue.\n");
2195 		goto reject;
2196 	}
2197 	text_ptr = strchr(text_in, '=');
2198 	if (!text_ptr) {
2199 		pr_err("No \"=\" separator found in Text Data,"
2200 			"  cannot continue.\n");
2201 		goto reject;
2202 	}
2203 	if (!strncmp("=All", text_ptr, 4)) {
2204 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2205 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2206 		   !strncmp("=eui.", text_ptr, 5)) {
2207 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2208 	} else {
2209 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2210 		goto reject;
2211 	}
2212 
2213 	spin_lock_bh(&conn->cmd_lock);
2214 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2215 	spin_unlock_bh(&conn->cmd_lock);
2216 
2217 empty_sendtargets:
2218 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2219 
2220 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2221 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2222 				(unsigned char *)hdr, hdr->cmdsn);
2223 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2224 			return -1;
2225 
2226 		return 0;
2227 	}
2228 
2229 	return iscsit_execute_cmd(cmd, 0);
2230 
2231 reject:
2232 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2233 				 (unsigned char *)hdr);
2234 }
2235 EXPORT_SYMBOL(iscsit_process_text_cmd);
2236 
2237 static int
2238 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2239 		       unsigned char *buf)
2240 {
2241 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2242 	char *text_in = NULL;
2243 	u32 payload_length = ntoh24(hdr->dlength);
2244 	int rx_size, rc;
2245 
2246 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2247 	if (rc < 0)
2248 		return 0;
2249 
2250 	rx_size = payload_length;
2251 	if (payload_length) {
2252 		u32 checksum = 0, data_crc = 0;
2253 		u32 padding = 0;
2254 		int niov = 0, rx_got;
2255 		struct kvec iov[2];
2256 
2257 		rx_size = ALIGN(payload_length, 4);
2258 		text_in = kzalloc(rx_size, GFP_KERNEL);
2259 		if (!text_in)
2260 			goto reject;
2261 
2262 		cmd->text_in_ptr = text_in;
2263 
2264 		memset(iov, 0, sizeof(iov));
2265 		iov[niov].iov_base	= text_in;
2266 		iov[niov++].iov_len	= rx_size;
2267 
2268 		padding = rx_size - payload_length;
2269 		if (padding)
2270 			pr_debug("Receiving %u additional bytes"
2271 					" for padding.\n", padding);
2272 		if (conn->conn_ops->DataDigest) {
2273 			iov[niov].iov_base	= &checksum;
2274 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2275 			rx_size += ISCSI_CRC_LEN;
2276 		}
2277 
2278 		WARN_ON_ONCE(niov > ARRAY_SIZE(iov));
2279 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2280 		if (rx_got != rx_size)
2281 			goto reject;
2282 
2283 		if (conn->conn_ops->DataDigest) {
2284 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2285 						  text_in, rx_size, 0, NULL,
2286 						  &data_crc);
2287 
2288 			if (checksum != data_crc) {
2289 				pr_err("Text data CRC32C DataDigest"
2290 					" 0x%08x does not match computed"
2291 					" 0x%08x\n", checksum, data_crc);
2292 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2293 					pr_err("Unable to recover from"
2294 					" Text Data digest failure while in"
2295 						" ERL=0.\n");
2296 					goto reject;
2297 				} else {
2298 					/*
2299 					 * Silently drop this PDU and let the
2300 					 * initiator plug the CmdSN gap.
2301 					 */
2302 					pr_debug("Dropping Text"
2303 					" Command CmdSN: 0x%08x due to"
2304 					" DataCRC error.\n", hdr->cmdsn);
2305 					kfree(text_in);
2306 					return 0;
2307 				}
2308 			} else {
2309 				pr_debug("Got CRC32C DataDigest"
2310 					" 0x%08x for %u bytes of text data.\n",
2311 						checksum, payload_length);
2312 			}
2313 		}
2314 		text_in[payload_length - 1] = '\0';
2315 		pr_debug("Successfully read %d bytes of text"
2316 				" data.\n", payload_length);
2317 	}
2318 
2319 	return iscsit_process_text_cmd(conn, cmd, hdr);
2320 
2321 reject:
2322 	kfree(cmd->text_in_ptr);
2323 	cmd->text_in_ptr = NULL;
2324 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2325 }
2326 
2327 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2328 {
2329 	struct iscsi_conn *conn_p;
2330 	struct iscsi_session *sess = conn->sess;
2331 
2332 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2333 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2334 
2335 	atomic_set(&sess->session_logout, 1);
2336 	atomic_set(&conn->conn_logout_remove, 1);
2337 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2338 
2339 	iscsit_inc_conn_usage_count(conn);
2340 	iscsit_inc_session_usage_count(sess);
2341 
2342 	spin_lock_bh(&sess->conn_lock);
2343 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2344 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2345 			continue;
2346 
2347 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2348 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2349 	}
2350 	spin_unlock_bh(&sess->conn_lock);
2351 
2352 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2353 
2354 	return 0;
2355 }
2356 
2357 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2358 {
2359 	struct iscsi_conn *l_conn;
2360 	struct iscsi_session *sess = conn->sess;
2361 
2362 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2363 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2364 
2365 	/*
2366 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2367 	 * can arrive on a connection with a differing CID.
2368 	 */
2369 	if (conn->cid == cmd->logout_cid) {
2370 		spin_lock_bh(&conn->state_lock);
2371 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2372 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2373 
2374 		atomic_set(&conn->conn_logout_remove, 1);
2375 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2376 		iscsit_inc_conn_usage_count(conn);
2377 
2378 		spin_unlock_bh(&conn->state_lock);
2379 	} else {
2380 		/*
2381 		 * Handle all different cid CLOSECONNECTION requests in
2382 		 * iscsit_logout_post_handler_diffcid() as to give enough
2383 		 * time for any non immediate command's CmdSN to be
2384 		 * acknowledged on the connection in question.
2385 		 *
2386 		 * Here we simply make sure the CID is still around.
2387 		 */
2388 		l_conn = iscsit_get_conn_from_cid(sess,
2389 				cmd->logout_cid);
2390 		if (!l_conn) {
2391 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2392 			iscsit_add_cmd_to_response_queue(cmd, conn,
2393 					cmd->i_state);
2394 			return 0;
2395 		}
2396 
2397 		iscsit_dec_conn_usage_count(l_conn);
2398 	}
2399 
2400 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2401 
2402 	return 0;
2403 }
2404 
2405 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2406 {
2407 	struct iscsi_session *sess = conn->sess;
2408 
2409 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2410 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2411 
2412 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2413 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2414 			" while ERL!=2.\n");
2415 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2416 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2417 		return 0;
2418 	}
2419 
2420 	if (conn->cid == cmd->logout_cid) {
2421 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2422 			" with CID: %hu on CID: %hu, implementation error.\n",
2423 				cmd->logout_cid, conn->cid);
2424 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2425 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2426 		return 0;
2427 	}
2428 
2429 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2430 
2431 	return 0;
2432 }
2433 
2434 int
2435 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2436 			unsigned char *buf)
2437 {
2438 	int cmdsn_ret, logout_remove = 0;
2439 	u8 reason_code = 0;
2440 	struct iscsi_logout *hdr;
2441 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2442 
2443 	hdr			= (struct iscsi_logout *) buf;
2444 	reason_code		= (hdr->flags & 0x7f);
2445 
2446 	if (tiqn) {
2447 		spin_lock(&tiqn->logout_stats.lock);
2448 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2449 			tiqn->logout_stats.normal_logouts++;
2450 		else
2451 			tiqn->logout_stats.abnormal_logouts++;
2452 		spin_unlock(&tiqn->logout_stats.lock);
2453 	}
2454 
2455 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2456 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2457 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2458 		hdr->cid, conn->cid);
2459 
2460 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2461 		pr_err("Received logout request on connection that"
2462 			" is not in logged in state, ignoring request.\n");
2463 		iscsit_free_cmd(cmd, false);
2464 		return 0;
2465 	}
2466 
2467 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2468 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2469 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2470 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2471 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2472 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2473 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2474 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2475 	cmd->logout_reason      = reason_code;
2476 	cmd->data_direction     = DMA_NONE;
2477 
2478 	/*
2479 	 * We need to sleep in these cases (by returning 1) until the Logout
2480 	 * Response gets sent in the tx thread.
2481 	 */
2482 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2483 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2484 	    be16_to_cpu(hdr->cid) == conn->cid))
2485 		logout_remove = 1;
2486 
2487 	spin_lock_bh(&conn->cmd_lock);
2488 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2489 	spin_unlock_bh(&conn->cmd_lock);
2490 
2491 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2492 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2493 
2494 	/*
2495 	 * Immediate commands are executed, well, immediately.
2496 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2497 	 */
2498 	if (cmd->immediate_cmd) {
2499 		int ret = iscsit_execute_cmd(cmd, 0);
2500 
2501 		if (ret < 0)
2502 			return ret;
2503 	} else {
2504 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2505 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2506 			logout_remove = 0;
2507 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2508 			return -1;
2509 	}
2510 
2511 	return logout_remove;
2512 }
2513 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2514 
2515 int iscsit_handle_snack(
2516 	struct iscsi_conn *conn,
2517 	unsigned char *buf)
2518 {
2519 	struct iscsi_snack *hdr;
2520 
2521 	hdr			= (struct iscsi_snack *) buf;
2522 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2523 
2524 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2525 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2526 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2527 			hdr->begrun, hdr->runlength, conn->cid);
2528 
2529 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2530 		pr_err("Initiator sent SNACK request while in"
2531 			" ErrorRecoveryLevel=0.\n");
2532 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2533 					 buf);
2534 	}
2535 	/*
2536 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2537 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2538 	 */
2539 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2540 	case 0:
2541 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2542 			hdr->itt,
2543 			be32_to_cpu(hdr->ttt),
2544 			be32_to_cpu(hdr->begrun),
2545 			be32_to_cpu(hdr->runlength));
2546 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2547 		return iscsit_handle_status_snack(conn, hdr->itt,
2548 			be32_to_cpu(hdr->ttt),
2549 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2550 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2551 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2552 			be32_to_cpu(hdr->begrun),
2553 			be32_to_cpu(hdr->runlength));
2554 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2555 		/* FIXME: Support R-Data SNACK */
2556 		pr_err("R-Data SNACK Not Supported.\n");
2557 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2558 					 buf);
2559 	default:
2560 		pr_err("Unknown SNACK type 0x%02x, protocol"
2561 			" error.\n", hdr->flags & 0x0f);
2562 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2563 					 buf);
2564 	}
2565 
2566 	return 0;
2567 }
2568 EXPORT_SYMBOL(iscsit_handle_snack);
2569 
2570 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2571 {
2572 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2573 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2574 		wait_for_completion_interruptible_timeout(
2575 					&conn->rx_half_close_comp,
2576 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2577 	}
2578 }
2579 
2580 static int iscsit_handle_immediate_data(
2581 	struct iscsi_cmd *cmd,
2582 	struct iscsi_scsi_req *hdr,
2583 	u32 length)
2584 {
2585 	int iov_ret, rx_got = 0, rx_size = 0;
2586 	u32 checksum, iov_count = 0, padding = 0;
2587 	struct iscsi_conn *conn = cmd->conn;
2588 	struct kvec *iov;
2589 	void *overflow_buf = NULL;
2590 
2591 	BUG_ON(cmd->write_data_done > cmd->se_cmd.data_length);
2592 	rx_size = min(cmd->se_cmd.data_length - cmd->write_data_done, length);
2593 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data,
2594 				   cmd->orig_iov_data_count - 2,
2595 				   cmd->write_data_done, rx_size);
2596 	if (iov_ret < 0)
2597 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2598 
2599 	iov_count = iov_ret;
2600 	iov = &cmd->iov_data[0];
2601 	if (rx_size < length) {
2602 		/*
2603 		 * Special case: length of immediate data exceeds the data
2604 		 * buffer size derived from the CDB.
2605 		 */
2606 		overflow_buf = kmalloc(length - rx_size, GFP_KERNEL);
2607 		if (!overflow_buf) {
2608 			iscsit_unmap_iovec(cmd);
2609 			return IMMEDIATE_DATA_CANNOT_RECOVER;
2610 		}
2611 		cmd->overflow_buf = overflow_buf;
2612 		iov[iov_count].iov_base = overflow_buf;
2613 		iov[iov_count].iov_len = length - rx_size;
2614 		iov_count++;
2615 		rx_size = length;
2616 	}
2617 
2618 	padding = ((-length) & 3);
2619 	if (padding != 0) {
2620 		iov[iov_count].iov_base	= cmd->pad_bytes;
2621 		iov[iov_count++].iov_len = padding;
2622 		rx_size += padding;
2623 	}
2624 
2625 	if (conn->conn_ops->DataDigest) {
2626 		iov[iov_count].iov_base		= &checksum;
2627 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2628 		rx_size += ISCSI_CRC_LEN;
2629 	}
2630 
2631 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
2632 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2633 
2634 	iscsit_unmap_iovec(cmd);
2635 
2636 	if (rx_got != rx_size) {
2637 		iscsit_rx_thread_wait_for_tcp(conn);
2638 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2639 	}
2640 
2641 	if (conn->conn_ops->DataDigest) {
2642 		u32 data_crc;
2643 
2644 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2645 						    cmd->write_data_done, length, padding,
2646 						    cmd->pad_bytes);
2647 
2648 		if (checksum != data_crc) {
2649 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2650 				" does not match computed 0x%08x\n", checksum,
2651 				data_crc);
2652 
2653 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2654 				pr_err("Unable to recover from"
2655 					" Immediate Data digest failure while"
2656 					" in ERL=0.\n");
2657 				iscsit_reject_cmd(cmd,
2658 						ISCSI_REASON_DATA_DIGEST_ERROR,
2659 						(unsigned char *)hdr);
2660 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2661 			} else {
2662 				iscsit_reject_cmd(cmd,
2663 						ISCSI_REASON_DATA_DIGEST_ERROR,
2664 						(unsigned char *)hdr);
2665 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2666 			}
2667 		} else {
2668 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2669 				" %u bytes of Immediate Data\n", checksum,
2670 				length);
2671 		}
2672 	}
2673 
2674 	cmd->write_data_done += length;
2675 
2676 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2677 		spin_lock_bh(&cmd->istate_lock);
2678 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2679 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2680 		spin_unlock_bh(&cmd->istate_lock);
2681 	}
2682 
2683 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2684 }
2685 
2686 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2687 	with active network interface */
2688 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2689 {
2690 	struct iscsi_cmd *cmd;
2691 	struct iscsi_conn *conn_p;
2692 	bool found = false;
2693 
2694 	lockdep_assert_held(&conn->sess->conn_lock);
2695 
2696 	/*
2697 	 * Only send a Asynchronous Message on connections whos network
2698 	 * interface is still functional.
2699 	 */
2700 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2701 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2702 			iscsit_inc_conn_usage_count(conn_p);
2703 			found = true;
2704 			break;
2705 		}
2706 	}
2707 
2708 	if (!found)
2709 		return;
2710 
2711 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2712 	if (!cmd) {
2713 		iscsit_dec_conn_usage_count(conn_p);
2714 		return;
2715 	}
2716 
2717 	cmd->logout_cid = conn->cid;
2718 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2719 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2720 
2721 	spin_lock_bh(&conn_p->cmd_lock);
2722 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2723 	spin_unlock_bh(&conn_p->cmd_lock);
2724 
2725 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2726 	iscsit_dec_conn_usage_count(conn_p);
2727 }
2728 
2729 static int iscsit_send_conn_drop_async_message(
2730 	struct iscsi_cmd *cmd,
2731 	struct iscsi_conn *conn)
2732 {
2733 	struct iscsi_async *hdr;
2734 
2735 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2736 
2737 	hdr			= (struct iscsi_async *) cmd->pdu;
2738 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2739 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2740 	cmd->init_task_tag	= RESERVED_ITT;
2741 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2742 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2743 	cmd->stat_sn		= conn->stat_sn++;
2744 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2745 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2746 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2747 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2748 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2749 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2750 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2751 
2752 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2753 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2754 			cmd->logout_cid, conn->cid);
2755 
2756 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2757 }
2758 
2759 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2760 {
2761 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2762 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2763 		wait_for_completion_interruptible_timeout(
2764 					&conn->tx_half_close_comp,
2765 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2766 	}
2767 }
2768 
2769 void
2770 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2771 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2772 			bool set_statsn)
2773 {
2774 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2775 	hdr->flags		= datain->flags;
2776 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2777 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2778 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2779 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2780 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2781 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2782 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2783 		}
2784 	}
2785 	hton24(hdr->dlength, datain->length);
2786 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2787 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2788 				(struct scsi_lun *)&hdr->lun);
2789 	else
2790 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2791 
2792 	hdr->itt		= cmd->init_task_tag;
2793 
2794 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2795 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2796 	else
2797 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2798 	if (set_statsn)
2799 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2800 	else
2801 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2802 
2803 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2804 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2805 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2806 	hdr->offset		= cpu_to_be32(datain->offset);
2807 
2808 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2809 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2810 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2811 		ntohl(hdr->offset), datain->length, conn->cid);
2812 }
2813 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2814 
2815 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2816 {
2817 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2818 	struct iscsi_datain datain;
2819 	struct iscsi_datain_req *dr;
2820 	int eodr = 0, ret;
2821 	bool set_statsn = false;
2822 
2823 	memset(&datain, 0, sizeof(struct iscsi_datain));
2824 	dr = iscsit_get_datain_values(cmd, &datain);
2825 	if (!dr) {
2826 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2827 				cmd->init_task_tag);
2828 		return -1;
2829 	}
2830 	/*
2831 	 * Be paranoid and double check the logic for now.
2832 	 */
2833 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2834 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2835 			" datain.length: %u exceeds cmd->data_length: %u\n",
2836 			cmd->init_task_tag, datain.offset, datain.length,
2837 			cmd->se_cmd.data_length);
2838 		return -1;
2839 	}
2840 
2841 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2842 	/*
2843 	 * Special case for successfully execution w/ both DATAIN
2844 	 * and Sense Data.
2845 	 */
2846 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2847 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2848 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2849 	else {
2850 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2851 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2852 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2853 			cmd->stat_sn = conn->stat_sn++;
2854 			set_statsn = true;
2855 		} else if (dr->dr_complete ==
2856 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2857 			set_statsn = true;
2858 	}
2859 
2860 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2861 
2862 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2863 	if (ret < 0)
2864 		return ret;
2865 
2866 	if (dr->dr_complete) {
2867 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2868 				2 : 1;
2869 		iscsit_free_datain_req(cmd, dr);
2870 	}
2871 
2872 	return eodr;
2873 }
2874 
2875 int
2876 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2877 			struct iscsi_logout_rsp *hdr)
2878 {
2879 	struct iscsi_conn *logout_conn = NULL;
2880 	struct iscsi_conn_recovery *cr = NULL;
2881 	struct iscsi_session *sess = conn->sess;
2882 	/*
2883 	 * The actual shutting down of Sessions and/or Connections
2884 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2885 	 * is done in scsi_logout_post_handler().
2886 	 */
2887 	switch (cmd->logout_reason) {
2888 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2889 		pr_debug("iSCSI session logout successful, setting"
2890 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2891 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2892 		break;
2893 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2894 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2895 			break;
2896 		/*
2897 		 * For CLOSECONNECTION logout requests carrying
2898 		 * a matching logout CID -> local CID, the reference
2899 		 * for the local CID will have been incremented in
2900 		 * iscsi_logout_closeconnection().
2901 		 *
2902 		 * For CLOSECONNECTION logout requests carrying
2903 		 * a different CID than the connection it arrived
2904 		 * on, the connection responding to cmd->logout_cid
2905 		 * is stopped in iscsit_logout_post_handler_diffcid().
2906 		 */
2907 
2908 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2909 			" successful.\n", cmd->logout_cid, conn->cid);
2910 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2911 		break;
2912 	case ISCSI_LOGOUT_REASON_RECOVERY:
2913 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2914 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2915 			break;
2916 		/*
2917 		 * If the connection is still active from our point of view
2918 		 * force connection recovery to occur.
2919 		 */
2920 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2921 				cmd->logout_cid);
2922 		if (logout_conn) {
2923 			iscsit_connection_reinstatement_rcfr(logout_conn);
2924 			iscsit_dec_conn_usage_count(logout_conn);
2925 		}
2926 
2927 		cr = iscsit_get_inactive_connection_recovery_entry(
2928 				conn->sess, cmd->logout_cid);
2929 		if (!cr) {
2930 			pr_err("Unable to locate CID: %hu for"
2931 			" REMOVECONNFORRECOVERY Logout Request.\n",
2932 				cmd->logout_cid);
2933 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2934 			break;
2935 		}
2936 
2937 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2938 
2939 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2940 			" for recovery for CID: %hu on CID: %hu successful.\n",
2941 				cmd->logout_cid, conn->cid);
2942 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2943 		break;
2944 	default:
2945 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2946 				cmd->logout_reason);
2947 		return -1;
2948 	}
2949 
2950 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2951 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2952 	hdr->response		= cmd->logout_response;
2953 	hdr->itt		= cmd->init_task_tag;
2954 	cmd->stat_sn		= conn->stat_sn++;
2955 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2956 
2957 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2958 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2959 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2960 
2961 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2962 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2963 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2964 		cmd->logout_cid, conn->cid);
2965 
2966 	return 0;
2967 }
2968 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2969 
2970 static int
2971 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2972 {
2973 	int rc;
2974 
2975 	rc = iscsit_build_logout_rsp(cmd, conn,
2976 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2977 	if (rc < 0)
2978 		return rc;
2979 
2980 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2981 }
2982 
2983 void
2984 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2985 		       struct iscsi_nopin *hdr, bool nopout_response)
2986 {
2987 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2988 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2989         hton24(hdr->dlength, cmd->buf_ptr_size);
2990 	if (nopout_response)
2991 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2992 	hdr->itt		= cmd->init_task_tag;
2993 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2994 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2995 				  conn->stat_sn;
2996 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2997 
2998 	if (nopout_response)
2999 		iscsit_increment_maxcmdsn(cmd, conn->sess);
3000 
3001 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3002 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3003 
3004 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
3005 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
3006 		"Solicited" : "Unsolicited", cmd->init_task_tag,
3007 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
3008 }
3009 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
3010 
3011 /*
3012  *	Unsolicited NOPIN, either requesting a response or not.
3013  */
3014 static int iscsit_send_unsolicited_nopin(
3015 	struct iscsi_cmd *cmd,
3016 	struct iscsi_conn *conn,
3017 	int want_response)
3018 {
3019 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3020 	int ret;
3021 
3022 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3023 
3024 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3025 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3026 
3027 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3028 	if (ret < 0)
3029 		return ret;
3030 
3031 	spin_lock_bh(&cmd->istate_lock);
3032 	cmd->i_state = want_response ?
3033 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3034 	spin_unlock_bh(&cmd->istate_lock);
3035 
3036 	return 0;
3037 }
3038 
3039 static int
3040 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3041 {
3042 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3043 
3044 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3045 
3046 	/*
3047 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
3048 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
3049 	 */
3050 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3051 
3052 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3053 						     cmd->buf_ptr,
3054 						     cmd->buf_ptr_size);
3055 }
3056 
3057 static int iscsit_send_r2t(
3058 	struct iscsi_cmd *cmd,
3059 	struct iscsi_conn *conn)
3060 {
3061 	struct iscsi_r2t *r2t;
3062 	struct iscsi_r2t_rsp *hdr;
3063 	int ret;
3064 
3065 	r2t = iscsit_get_r2t_from_list(cmd);
3066 	if (!r2t)
3067 		return -1;
3068 
3069 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3070 	memset(hdr, 0, ISCSI_HDR_LEN);
3071 	hdr->opcode		= ISCSI_OP_R2T;
3072 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3073 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3074 			(struct scsi_lun *)&hdr->lun);
3075 	hdr->itt		= cmd->init_task_tag;
3076 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3077 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3078 	else
3079 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3080 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3081 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3082 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3083 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3084 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3085 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3086 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3087 
3088 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3089 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3090 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3091 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3092 			r2t->offset, r2t->xfer_len, conn->cid);
3093 
3094 	spin_lock_bh(&cmd->r2t_lock);
3095 	r2t->sent_r2t = 1;
3096 	spin_unlock_bh(&cmd->r2t_lock);
3097 
3098 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3099 	if (ret < 0) {
3100 		return ret;
3101 	}
3102 
3103 	spin_lock_bh(&cmd->dataout_timeout_lock);
3104 	iscsit_start_dataout_timer(cmd, conn);
3105 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3106 
3107 	return 0;
3108 }
3109 
3110 /*
3111  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3112  *		connection recovery.
3113  */
3114 int iscsit_build_r2ts_for_cmd(
3115 	struct iscsi_conn *conn,
3116 	struct iscsi_cmd *cmd,
3117 	bool recovery)
3118 {
3119 	int first_r2t = 1;
3120 	u32 offset = 0, xfer_len = 0;
3121 
3122 	spin_lock_bh(&cmd->r2t_lock);
3123 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3124 		spin_unlock_bh(&cmd->r2t_lock);
3125 		return 0;
3126 	}
3127 
3128 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3129 	    !recovery)
3130 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3131 
3132 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3133 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3134 			offset = cmd->r2t_offset;
3135 
3136 			if (first_r2t && recovery) {
3137 				int new_data_end = offset +
3138 					conn->sess->sess_ops->MaxBurstLength -
3139 					cmd->next_burst_len;
3140 
3141 				if (new_data_end > cmd->se_cmd.data_length)
3142 					xfer_len = cmd->se_cmd.data_length - offset;
3143 				else
3144 					xfer_len =
3145 						conn->sess->sess_ops->MaxBurstLength -
3146 						cmd->next_burst_len;
3147 			} else {
3148 				int new_data_end = offset +
3149 					conn->sess->sess_ops->MaxBurstLength;
3150 
3151 				if (new_data_end > cmd->se_cmd.data_length)
3152 					xfer_len = cmd->se_cmd.data_length - offset;
3153 				else
3154 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3155 			}
3156 
3157 			if ((s32)xfer_len < 0) {
3158 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3159 				break;
3160 			}
3161 
3162 			cmd->r2t_offset += xfer_len;
3163 
3164 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3165 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3166 		} else {
3167 			struct iscsi_seq *seq;
3168 
3169 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3170 			if (!seq) {
3171 				spin_unlock_bh(&cmd->r2t_lock);
3172 				return -1;
3173 			}
3174 
3175 			offset = seq->offset;
3176 			xfer_len = seq->xfer_len;
3177 
3178 			if (cmd->seq_send_order == cmd->seq_count)
3179 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3180 		}
3181 		cmd->outstanding_r2ts++;
3182 		first_r2t = 0;
3183 
3184 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3185 			spin_unlock_bh(&cmd->r2t_lock);
3186 			return -1;
3187 		}
3188 
3189 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3190 			break;
3191 	}
3192 	spin_unlock_bh(&cmd->r2t_lock);
3193 
3194 	return 0;
3195 }
3196 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3197 
3198 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3199 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3200 {
3201 	if (inc_stat_sn)
3202 		cmd->stat_sn = conn->stat_sn++;
3203 
3204 	atomic_long_inc(&conn->sess->rsp_pdus);
3205 
3206 	memset(hdr, 0, ISCSI_HDR_LEN);
3207 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3208 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3209 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3210 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3211 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3212 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3213 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3214 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3215 	}
3216 	hdr->response		= cmd->iscsi_response;
3217 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3218 	hdr->itt		= cmd->init_task_tag;
3219 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3220 
3221 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3222 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3223 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3224 
3225 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3226 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3227 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3228 		cmd->se_cmd.scsi_status, conn->cid);
3229 }
3230 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3231 
3232 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3233 {
3234 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3235 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3236 	void *data_buf = NULL;
3237 	u32 padding = 0, data_buf_len = 0;
3238 
3239 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3240 
3241 	/*
3242 	 * Attach SENSE DATA payload to iSCSI Response PDU
3243 	 */
3244 	if (cmd->se_cmd.sense_buffer &&
3245 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3246 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3247 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3248 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3249 
3250 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3251 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3252 		data_buf = cmd->sense_buffer;
3253 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3254 
3255 		if (padding) {
3256 			memset(cmd->sense_buffer +
3257 				cmd->se_cmd.scsi_sense_length, 0, padding);
3258 			pr_debug("Adding %u bytes of padding to"
3259 				" SENSE.\n", padding);
3260 		}
3261 
3262 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3263 				" Response PDU\n",
3264 				cmd->se_cmd.scsi_sense_length);
3265 	}
3266 
3267 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3268 						     data_buf_len);
3269 }
3270 
3271 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3272 {
3273 	switch (se_tmr->response) {
3274 	case TMR_FUNCTION_COMPLETE:
3275 		return ISCSI_TMF_RSP_COMPLETE;
3276 	case TMR_TASK_DOES_NOT_EXIST:
3277 		return ISCSI_TMF_RSP_NO_TASK;
3278 	case TMR_LUN_DOES_NOT_EXIST:
3279 		return ISCSI_TMF_RSP_NO_LUN;
3280 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3281 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3282 	case TMR_FUNCTION_REJECTED:
3283 	default:
3284 		return ISCSI_TMF_RSP_REJECTED;
3285 	}
3286 }
3287 
3288 void
3289 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3290 			  struct iscsi_tm_rsp *hdr)
3291 {
3292 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3293 
3294 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3295 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3296 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3297 	hdr->itt		= cmd->init_task_tag;
3298 	cmd->stat_sn		= conn->stat_sn++;
3299 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3300 
3301 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3302 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3303 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3304 
3305 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3306 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3307 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3308 }
3309 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3310 
3311 static int
3312 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3313 {
3314 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3315 
3316 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3317 
3318 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3319 }
3320 
3321 #define SENDTARGETS_BUF_LIMIT 32768U
3322 
3323 static int
3324 iscsit_build_sendtargets_response(struct iscsi_cmd *cmd,
3325 				  enum iscsit_transport_type network_transport,
3326 				  int skip_bytes, bool *completed)
3327 {
3328 	char *payload = NULL;
3329 	struct iscsi_conn *conn = cmd->conn;
3330 	struct iscsi_portal_group *tpg;
3331 	struct iscsi_tiqn *tiqn;
3332 	struct iscsi_tpg_np *tpg_np;
3333 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3334 	int target_name_printed;
3335 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3336 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3337 	bool active;
3338 
3339 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3340 			 SENDTARGETS_BUF_LIMIT);
3341 
3342 	payload = kzalloc(buffer_len, GFP_KERNEL);
3343 	if (!payload)
3344 		return -ENOMEM;
3345 
3346 	/*
3347 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3348 	 * explicit case..
3349 	 */
3350 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3351 		text_ptr = strchr(text_in, '=');
3352 		if (!text_ptr) {
3353 			pr_err("Unable to locate '=' string in text_in:"
3354 			       " %s\n", text_in);
3355 			kfree(payload);
3356 			return -EINVAL;
3357 		}
3358 		/*
3359 		 * Skip over '=' character..
3360 		 */
3361 		text_ptr += 1;
3362 	}
3363 
3364 	spin_lock(&tiqn_lock);
3365 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3366 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3367 		     strcmp(tiqn->tiqn, text_ptr)) {
3368 			continue;
3369 		}
3370 
3371 		target_name_printed = 0;
3372 
3373 		spin_lock(&tiqn->tiqn_tpg_lock);
3374 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3375 
3376 			/* If demo_mode_discovery=0 and generate_node_acls=0
3377 			 * (demo mode dislabed) do not return
3378 			 * TargetName+TargetAddress unless a NodeACL exists.
3379 			 */
3380 
3381 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3382 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3383 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3384 				cmd->conn->sess->sess_ops->InitiatorName))) {
3385 				continue;
3386 			}
3387 
3388 			spin_lock(&tpg->tpg_state_lock);
3389 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3390 			spin_unlock(&tpg->tpg_state_lock);
3391 
3392 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3393 				continue;
3394 
3395 			spin_lock(&tpg->tpg_np_lock);
3396 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3397 						tpg_np_list) {
3398 				struct iscsi_np *np = tpg_np->tpg_np;
3399 				struct sockaddr_storage *sockaddr;
3400 
3401 				if (np->np_network_transport != network_transport)
3402 					continue;
3403 
3404 				if (!target_name_printed) {
3405 					len = sprintf(buf, "TargetName=%s",
3406 						      tiqn->tiqn);
3407 					len += 1;
3408 
3409 					if ((len + payload_len) > buffer_len) {
3410 						spin_unlock(&tpg->tpg_np_lock);
3411 						spin_unlock(&tiqn->tiqn_tpg_lock);
3412 						end_of_buf = 1;
3413 						goto eob;
3414 					}
3415 
3416 					if (skip_bytes && len <= skip_bytes) {
3417 						skip_bytes -= len;
3418 					} else {
3419 						memcpy(payload + payload_len, buf, len);
3420 						payload_len += len;
3421 						target_name_printed = 1;
3422 						if (len > skip_bytes)
3423 							skip_bytes = 0;
3424 					}
3425 				}
3426 
3427 				if (inet_addr_is_any((struct sockaddr *)&np->np_sockaddr))
3428 					sockaddr = &conn->local_sockaddr;
3429 				else
3430 					sockaddr = &np->np_sockaddr;
3431 
3432 				len = sprintf(buf, "TargetAddress="
3433 					      "%pISpc,%hu",
3434 					      sockaddr,
3435 					      tpg->tpgt);
3436 				len += 1;
3437 
3438 				if ((len + payload_len) > buffer_len) {
3439 					spin_unlock(&tpg->tpg_np_lock);
3440 					spin_unlock(&tiqn->tiqn_tpg_lock);
3441 					end_of_buf = 1;
3442 					goto eob;
3443 				}
3444 
3445 				if (skip_bytes && len <= skip_bytes) {
3446 					skip_bytes -= len;
3447 				} else {
3448 					memcpy(payload + payload_len, buf, len);
3449 					payload_len += len;
3450 					if (len > skip_bytes)
3451 						skip_bytes = 0;
3452 				}
3453 			}
3454 			spin_unlock(&tpg->tpg_np_lock);
3455 		}
3456 		spin_unlock(&tiqn->tiqn_tpg_lock);
3457 eob:
3458 		if (end_of_buf) {
3459 			*completed = false;
3460 			break;
3461 		}
3462 
3463 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3464 			break;
3465 	}
3466 	spin_unlock(&tiqn_lock);
3467 
3468 	cmd->buf_ptr = payload;
3469 
3470 	return payload_len;
3471 }
3472 
3473 int
3474 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3475 		      struct iscsi_text_rsp *hdr,
3476 		      enum iscsit_transport_type network_transport)
3477 {
3478 	int text_length, padding;
3479 	bool completed = true;
3480 
3481 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3482 							cmd->read_data_done,
3483 							&completed);
3484 	if (text_length < 0)
3485 		return text_length;
3486 
3487 	if (completed) {
3488 		hdr->flags = ISCSI_FLAG_CMD_FINAL;
3489 	} else {
3490 		hdr->flags = ISCSI_FLAG_TEXT_CONTINUE;
3491 		cmd->read_data_done += text_length;
3492 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3493 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3494 	}
3495 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3496 	padding = ((-text_length) & 3);
3497 	hton24(hdr->dlength, text_length);
3498 	hdr->itt = cmd->init_task_tag;
3499 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3500 	cmd->stat_sn = conn->stat_sn++;
3501 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3502 
3503 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3504 	/*
3505 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3506 	 * correctly increment MaxCmdSN for each response answering a
3507 	 * non immediate text request with a valid CmdSN.
3508 	 */
3509 	cmd->maxcmdsn_inc = 0;
3510 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3511 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3512 
3513 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3514 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3515 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3516 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3517 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3518 
3519 	return text_length + padding;
3520 }
3521 EXPORT_SYMBOL(iscsit_build_text_rsp);
3522 
3523 static int iscsit_send_text_rsp(
3524 	struct iscsi_cmd *cmd,
3525 	struct iscsi_conn *conn)
3526 {
3527 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3528 	int text_length;
3529 
3530 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3531 				conn->conn_transport->transport_type);
3532 	if (text_length < 0)
3533 		return text_length;
3534 
3535 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3536 						     cmd->buf_ptr,
3537 						     text_length);
3538 }
3539 
3540 void
3541 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3542 		    struct iscsi_reject *hdr)
3543 {
3544 	hdr->opcode		= ISCSI_OP_REJECT;
3545 	hdr->reason		= cmd->reject_reason;
3546 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3547 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3548 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3549 	cmd->stat_sn		= conn->stat_sn++;
3550 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3551 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3552 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3553 
3554 }
3555 EXPORT_SYMBOL(iscsit_build_reject);
3556 
3557 static int iscsit_send_reject(
3558 	struct iscsi_cmd *cmd,
3559 	struct iscsi_conn *conn)
3560 {
3561 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3562 
3563 	iscsit_build_reject(cmd, conn, hdr);
3564 
3565 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3566 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3567 
3568 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3569 						     cmd->buf_ptr,
3570 						     ISCSI_HDR_LEN);
3571 }
3572 
3573 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3574 {
3575 	int ord, cpu;
3576 	/*
3577 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3578 	 * within iscsit_start_kthreads()
3579 	 *
3580 	 * Here we use bitmap_id to determine which CPU that this
3581 	 * iSCSI connection's RX/TX threads will be scheduled to
3582 	 * execute upon.
3583 	 */
3584 	ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3585 	for_each_online_cpu(cpu) {
3586 		if (ord-- == 0) {
3587 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3588 			return;
3589 		}
3590 	}
3591 	/*
3592 	 * This should never be reached..
3593 	 */
3594 	dump_stack();
3595 	cpumask_setall(conn->conn_cpumask);
3596 }
3597 
3598 int
3599 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3600 {
3601 	int ret;
3602 
3603 	switch (state) {
3604 	case ISTATE_SEND_R2T:
3605 		ret = iscsit_send_r2t(cmd, conn);
3606 		if (ret < 0)
3607 			goto err;
3608 		break;
3609 	case ISTATE_REMOVE:
3610 		spin_lock_bh(&conn->cmd_lock);
3611 		list_del_init(&cmd->i_conn_node);
3612 		spin_unlock_bh(&conn->cmd_lock);
3613 
3614 		iscsit_free_cmd(cmd, false);
3615 		break;
3616 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3617 		iscsit_mod_nopin_response_timer(conn);
3618 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3619 		if (ret < 0)
3620 			goto err;
3621 		break;
3622 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3623 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3624 		if (ret < 0)
3625 			goto err;
3626 		break;
3627 	default:
3628 		pr_err("Unknown Opcode: 0x%02x ITT:"
3629 		       " 0x%08x, i_state: %d on CID: %hu\n",
3630 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3631 		       conn->cid);
3632 		goto err;
3633 	}
3634 
3635 	return 0;
3636 
3637 err:
3638 	return -1;
3639 }
3640 EXPORT_SYMBOL(iscsit_immediate_queue);
3641 
3642 static int
3643 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3644 {
3645 	struct iscsit_transport *t = conn->conn_transport;
3646 	struct iscsi_queue_req *qr;
3647 	struct iscsi_cmd *cmd;
3648 	u8 state;
3649 	int ret;
3650 
3651 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3652 		atomic_set(&conn->check_immediate_queue, 0);
3653 		cmd = qr->cmd;
3654 		state = qr->state;
3655 		kmem_cache_free(lio_qr_cache, qr);
3656 
3657 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3658 		if (ret < 0)
3659 			return ret;
3660 	}
3661 
3662 	return 0;
3663 }
3664 
3665 int
3666 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3667 {
3668 	int ret;
3669 
3670 check_rsp_state:
3671 	switch (state) {
3672 	case ISTATE_SEND_DATAIN:
3673 		ret = iscsit_send_datain(cmd, conn);
3674 		if (ret < 0)
3675 			goto err;
3676 		else if (!ret)
3677 			/* more drs */
3678 			goto check_rsp_state;
3679 		else if (ret == 1) {
3680 			/* all done */
3681 			spin_lock_bh(&cmd->istate_lock);
3682 			cmd->i_state = ISTATE_SENT_STATUS;
3683 			spin_unlock_bh(&cmd->istate_lock);
3684 
3685 			if (atomic_read(&conn->check_immediate_queue))
3686 				return 1;
3687 
3688 			return 0;
3689 		} else if (ret == 2) {
3690 			/* Still must send status,
3691 			   SCF_TRANSPORT_TASK_SENSE was set */
3692 			spin_lock_bh(&cmd->istate_lock);
3693 			cmd->i_state = ISTATE_SEND_STATUS;
3694 			spin_unlock_bh(&cmd->istate_lock);
3695 			state = ISTATE_SEND_STATUS;
3696 			goto check_rsp_state;
3697 		}
3698 
3699 		break;
3700 	case ISTATE_SEND_STATUS:
3701 	case ISTATE_SEND_STATUS_RECOVERY:
3702 		ret = iscsit_send_response(cmd, conn);
3703 		break;
3704 	case ISTATE_SEND_LOGOUTRSP:
3705 		ret = iscsit_send_logout(cmd, conn);
3706 		break;
3707 	case ISTATE_SEND_ASYNCMSG:
3708 		ret = iscsit_send_conn_drop_async_message(
3709 			cmd, conn);
3710 		break;
3711 	case ISTATE_SEND_NOPIN:
3712 		ret = iscsit_send_nopin(cmd, conn);
3713 		break;
3714 	case ISTATE_SEND_REJECT:
3715 		ret = iscsit_send_reject(cmd, conn);
3716 		break;
3717 	case ISTATE_SEND_TASKMGTRSP:
3718 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3719 		if (ret != 0)
3720 			break;
3721 		ret = iscsit_tmr_post_handler(cmd, conn);
3722 		if (ret != 0)
3723 			iscsit_fall_back_to_erl0(conn->sess);
3724 		break;
3725 	case ISTATE_SEND_TEXTRSP:
3726 		ret = iscsit_send_text_rsp(cmd, conn);
3727 		break;
3728 	default:
3729 		pr_err("Unknown Opcode: 0x%02x ITT:"
3730 		       " 0x%08x, i_state: %d on CID: %hu\n",
3731 		       cmd->iscsi_opcode, cmd->init_task_tag,
3732 		       state, conn->cid);
3733 		goto err;
3734 	}
3735 	if (ret < 0)
3736 		goto err;
3737 
3738 	switch (state) {
3739 	case ISTATE_SEND_LOGOUTRSP:
3740 		if (!iscsit_logout_post_handler(cmd, conn))
3741 			return -ECONNRESET;
3742 		/* fall through */
3743 	case ISTATE_SEND_STATUS:
3744 	case ISTATE_SEND_ASYNCMSG:
3745 	case ISTATE_SEND_NOPIN:
3746 	case ISTATE_SEND_STATUS_RECOVERY:
3747 	case ISTATE_SEND_TEXTRSP:
3748 	case ISTATE_SEND_TASKMGTRSP:
3749 	case ISTATE_SEND_REJECT:
3750 		spin_lock_bh(&cmd->istate_lock);
3751 		cmd->i_state = ISTATE_SENT_STATUS;
3752 		spin_unlock_bh(&cmd->istate_lock);
3753 		break;
3754 	default:
3755 		pr_err("Unknown Opcode: 0x%02x ITT:"
3756 		       " 0x%08x, i_state: %d on CID: %hu\n",
3757 		       cmd->iscsi_opcode, cmd->init_task_tag,
3758 		       cmd->i_state, conn->cid);
3759 		goto err;
3760 	}
3761 
3762 	if (atomic_read(&conn->check_immediate_queue))
3763 		return 1;
3764 
3765 	return 0;
3766 
3767 err:
3768 	return -1;
3769 }
3770 EXPORT_SYMBOL(iscsit_response_queue);
3771 
3772 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3773 {
3774 	struct iscsit_transport *t = conn->conn_transport;
3775 	struct iscsi_queue_req *qr;
3776 	struct iscsi_cmd *cmd;
3777 	u8 state;
3778 	int ret;
3779 
3780 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3781 		cmd = qr->cmd;
3782 		state = qr->state;
3783 		kmem_cache_free(lio_qr_cache, qr);
3784 
3785 		ret = t->iscsit_response_queue(conn, cmd, state);
3786 		if (ret == 1 || ret < 0)
3787 			return ret;
3788 	}
3789 
3790 	return 0;
3791 }
3792 
3793 int iscsi_target_tx_thread(void *arg)
3794 {
3795 	int ret = 0;
3796 	struct iscsi_conn *conn = arg;
3797 	bool conn_freed = false;
3798 
3799 	/*
3800 	 * Allow ourselves to be interrupted by SIGINT so that a
3801 	 * connection recovery / failure event can be triggered externally.
3802 	 */
3803 	allow_signal(SIGINT);
3804 
3805 	while (!kthread_should_stop()) {
3806 		/*
3807 		 * Ensure that both TX and RX per connection kthreads
3808 		 * are scheduled to run on the same CPU.
3809 		 */
3810 		iscsit_thread_check_cpumask(conn, current, 1);
3811 
3812 		wait_event_interruptible(conn->queues_wq,
3813 					 !iscsit_conn_all_queues_empty(conn));
3814 
3815 		if (signal_pending(current))
3816 			goto transport_err;
3817 
3818 get_immediate:
3819 		ret = iscsit_handle_immediate_queue(conn);
3820 		if (ret < 0)
3821 			goto transport_err;
3822 
3823 		ret = iscsit_handle_response_queue(conn);
3824 		if (ret == 1) {
3825 			goto get_immediate;
3826 		} else if (ret == -ECONNRESET) {
3827 			conn_freed = true;
3828 			goto out;
3829 		} else if (ret < 0) {
3830 			goto transport_err;
3831 		}
3832 	}
3833 
3834 transport_err:
3835 	/*
3836 	 * Avoid the normal connection failure code-path if this connection
3837 	 * is still within LOGIN mode, and iscsi_np process context is
3838 	 * responsible for cleaning up the early connection failure.
3839 	 */
3840 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3841 		iscsit_take_action_for_connection_exit(conn, &conn_freed);
3842 out:
3843 	if (!conn_freed) {
3844 		while (!kthread_should_stop()) {
3845 			msleep(100);
3846 		}
3847 	}
3848 	return 0;
3849 }
3850 
3851 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3852 {
3853 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3854 	struct iscsi_cmd *cmd;
3855 	int ret = 0;
3856 
3857 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3858 	case ISCSI_OP_SCSI_CMD:
3859 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3860 		if (!cmd)
3861 			goto reject;
3862 
3863 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3864 		break;
3865 	case ISCSI_OP_SCSI_DATA_OUT:
3866 		ret = iscsit_handle_data_out(conn, buf);
3867 		break;
3868 	case ISCSI_OP_NOOP_OUT:
3869 		cmd = NULL;
3870 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3871 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3872 			if (!cmd)
3873 				goto reject;
3874 		}
3875 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3876 		break;
3877 	case ISCSI_OP_SCSI_TMFUNC:
3878 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3879 		if (!cmd)
3880 			goto reject;
3881 
3882 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3883 		break;
3884 	case ISCSI_OP_TEXT:
3885 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3886 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3887 			if (!cmd)
3888 				goto reject;
3889 		} else {
3890 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3891 			if (!cmd)
3892 				goto reject;
3893 		}
3894 
3895 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3896 		break;
3897 	case ISCSI_OP_LOGOUT:
3898 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3899 		if (!cmd)
3900 			goto reject;
3901 
3902 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3903 		if (ret > 0)
3904 			wait_for_completion_timeout(&conn->conn_logout_comp,
3905 					SECONDS_FOR_LOGOUT_COMP * HZ);
3906 		break;
3907 	case ISCSI_OP_SNACK:
3908 		ret = iscsit_handle_snack(conn, buf);
3909 		break;
3910 	default:
3911 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3912 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3913 			pr_err("Cannot recover from unknown"
3914 			" opcode while ERL=0, closing iSCSI connection.\n");
3915 			return -1;
3916 		}
3917 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
3918 		       " closing iSCSI connection.\n");
3919 		ret = -1;
3920 		break;
3921 	}
3922 
3923 	return ret;
3924 reject:
3925 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
3926 }
3927 
3928 static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
3929 {
3930 	bool ret;
3931 
3932 	spin_lock_bh(&conn->state_lock);
3933 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
3934 	spin_unlock_bh(&conn->state_lock);
3935 
3936 	return ret;
3937 }
3938 
3939 static void iscsit_get_rx_pdu(struct iscsi_conn *conn)
3940 {
3941 	int ret;
3942 	u8 *buffer, opcode;
3943 	u32 checksum = 0, digest = 0;
3944 	struct kvec iov;
3945 
3946 	buffer = kcalloc(ISCSI_HDR_LEN, sizeof(*buffer), GFP_KERNEL);
3947 	if (!buffer)
3948 		return;
3949 
3950 	while (!kthread_should_stop()) {
3951 		/*
3952 		 * Ensure that both TX and RX per connection kthreads
3953 		 * are scheduled to run on the same CPU.
3954 		 */
3955 		iscsit_thread_check_cpumask(conn, current, 0);
3956 
3957 		memset(&iov, 0, sizeof(struct kvec));
3958 
3959 		iov.iov_base	= buffer;
3960 		iov.iov_len	= ISCSI_HDR_LEN;
3961 
3962 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
3963 		if (ret != ISCSI_HDR_LEN) {
3964 			iscsit_rx_thread_wait_for_tcp(conn);
3965 			break;
3966 		}
3967 
3968 		if (conn->conn_ops->HeaderDigest) {
3969 			iov.iov_base	= &digest;
3970 			iov.iov_len	= ISCSI_CRC_LEN;
3971 
3972 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
3973 			if (ret != ISCSI_CRC_LEN) {
3974 				iscsit_rx_thread_wait_for_tcp(conn);
3975 				break;
3976 			}
3977 
3978 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, buffer,
3979 						  ISCSI_HDR_LEN, 0, NULL,
3980 						  &checksum);
3981 
3982 			if (digest != checksum) {
3983 				pr_err("HeaderDigest CRC32C failed,"
3984 					" received 0x%08x, computed 0x%08x\n",
3985 					digest, checksum);
3986 				/*
3987 				 * Set the PDU to 0xff so it will intentionally
3988 				 * hit default in the switch below.
3989 				 */
3990 				memset(buffer, 0xff, ISCSI_HDR_LEN);
3991 				atomic_long_inc(&conn->sess->conn_digest_errors);
3992 			} else {
3993 				pr_debug("Got HeaderDigest CRC32C"
3994 						" 0x%08x\n", checksum);
3995 			}
3996 		}
3997 
3998 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
3999 			break;
4000 
4001 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4002 
4003 		if (conn->sess->sess_ops->SessionType &&
4004 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4005 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4006 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4007 			" while in Discovery Session, rejecting.\n", opcode);
4008 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4009 					  buffer);
4010 			break;
4011 		}
4012 
4013 		ret = iscsi_target_rx_opcode(conn, buffer);
4014 		if (ret < 0)
4015 			break;
4016 	}
4017 
4018 	kfree(buffer);
4019 }
4020 
4021 int iscsi_target_rx_thread(void *arg)
4022 {
4023 	int rc;
4024 	struct iscsi_conn *conn = arg;
4025 	bool conn_freed = false;
4026 
4027 	/*
4028 	 * Allow ourselves to be interrupted by SIGINT so that a
4029 	 * connection recovery / failure event can be triggered externally.
4030 	 */
4031 	allow_signal(SIGINT);
4032 	/*
4033 	 * Wait for iscsi_post_login_handler() to complete before allowing
4034 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4035 	 */
4036 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4037 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4038 		goto out;
4039 
4040 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4041 		return 0;
4042 
4043 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4044 
4045 	if (!signal_pending(current))
4046 		atomic_set(&conn->transport_failed, 1);
4047 	iscsit_take_action_for_connection_exit(conn, &conn_freed);
4048 
4049 out:
4050 	if (!conn_freed) {
4051 		while (!kthread_should_stop()) {
4052 			msleep(100);
4053 		}
4054 	}
4055 
4056 	return 0;
4057 }
4058 
4059 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4060 {
4061 	LIST_HEAD(tmp_list);
4062 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4063 	struct iscsi_session *sess = conn->sess;
4064 	/*
4065 	 * We expect this function to only ever be called from either RX or TX
4066 	 * thread context via iscsit_close_connection() once the other context
4067 	 * has been reset -> returned sleeping pre-handler state.
4068 	 */
4069 	spin_lock_bh(&conn->cmd_lock);
4070 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4071 
4072 	list_for_each_entry(cmd, &tmp_list, i_conn_node) {
4073 		struct se_cmd *se_cmd = &cmd->se_cmd;
4074 
4075 		if (se_cmd->se_tfo != NULL) {
4076 			spin_lock_irq(&se_cmd->t_state_lock);
4077 			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4078 			spin_unlock_irq(&se_cmd->t_state_lock);
4079 		}
4080 	}
4081 	spin_unlock_bh(&conn->cmd_lock);
4082 
4083 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4084 		list_del_init(&cmd->i_conn_node);
4085 
4086 		iscsit_increment_maxcmdsn(cmd, sess);
4087 		iscsit_free_cmd(cmd, true);
4088 
4089 	}
4090 }
4091 
4092 static void iscsit_stop_timers_for_cmds(
4093 	struct iscsi_conn *conn)
4094 {
4095 	struct iscsi_cmd *cmd;
4096 
4097 	spin_lock_bh(&conn->cmd_lock);
4098 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4099 		if (cmd->data_direction == DMA_TO_DEVICE)
4100 			iscsit_stop_dataout_timer(cmd);
4101 	}
4102 	spin_unlock_bh(&conn->cmd_lock);
4103 }
4104 
4105 int iscsit_close_connection(
4106 	struct iscsi_conn *conn)
4107 {
4108 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4109 	struct iscsi_session	*sess = conn->sess;
4110 
4111 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4112 		" %u\n", conn->cid, sess->sid);
4113 	/*
4114 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4115 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4116 	 * sleeping and the logout response never got sent because the
4117 	 * connection failed.
4118 	 *
4119 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4120 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4121 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4122 	 * and to avoid iscsi_conn pointer dereference in iser-target code.
4123 	 */
4124 	if (!conn->conn_transport->rdma_shutdown)
4125 		complete(&conn->conn_logout_comp);
4126 
4127 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4128 		if (conn->tx_thread &&
4129 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4130 			send_sig(SIGINT, conn->tx_thread, 1);
4131 			kthread_stop(conn->tx_thread);
4132 		}
4133 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4134 		if (conn->rx_thread &&
4135 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4136 			send_sig(SIGINT, conn->rx_thread, 1);
4137 			kthread_stop(conn->rx_thread);
4138 		}
4139 	}
4140 
4141 	spin_lock(&iscsit_global->ts_bitmap_lock);
4142 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4143 			      get_order(1));
4144 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4145 
4146 	iscsit_stop_timers_for_cmds(conn);
4147 	iscsit_stop_nopin_response_timer(conn);
4148 	iscsit_stop_nopin_timer(conn);
4149 
4150 	if (conn->conn_transport->iscsit_wait_conn)
4151 		conn->conn_transport->iscsit_wait_conn(conn);
4152 
4153 	/*
4154 	 * During Connection recovery drop unacknowledged out of order
4155 	 * commands for this connection, and prepare the other commands
4156 	 * for reallegiance.
4157 	 *
4158 	 * During normal operation clear the out of order commands (but
4159 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4160 	 * struct iscsi_cmds.
4161 	 */
4162 	if (atomic_read(&conn->connection_recovery)) {
4163 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4164 		iscsit_prepare_cmds_for_reallegiance(conn);
4165 	} else {
4166 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4167 		iscsit_release_commands_from_conn(conn);
4168 	}
4169 	iscsit_free_queue_reqs_for_conn(conn);
4170 
4171 	/*
4172 	 * Handle decrementing session or connection usage count if
4173 	 * a logout response was not able to be sent because the
4174 	 * connection failed.  Fall back to Session Recovery here.
4175 	 */
4176 	if (atomic_read(&conn->conn_logout_remove)) {
4177 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4178 			iscsit_dec_conn_usage_count(conn);
4179 			iscsit_dec_session_usage_count(sess);
4180 		}
4181 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4182 			iscsit_dec_conn_usage_count(conn);
4183 
4184 		atomic_set(&conn->conn_logout_remove, 0);
4185 		atomic_set(&sess->session_reinstatement, 0);
4186 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4187 	}
4188 
4189 	spin_lock_bh(&sess->conn_lock);
4190 	list_del(&conn->conn_list);
4191 
4192 	/*
4193 	 * Attempt to let the Initiator know this connection failed by
4194 	 * sending an Connection Dropped Async Message on another
4195 	 * active connection.
4196 	 */
4197 	if (atomic_read(&conn->connection_recovery))
4198 		iscsit_build_conn_drop_async_message(conn);
4199 
4200 	spin_unlock_bh(&sess->conn_lock);
4201 
4202 	/*
4203 	 * If connection reinstatement is being performed on this connection,
4204 	 * up the connection reinstatement semaphore that is being blocked on
4205 	 * in iscsit_cause_connection_reinstatement().
4206 	 */
4207 	spin_lock_bh(&conn->state_lock);
4208 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4209 		spin_unlock_bh(&conn->state_lock);
4210 		complete(&conn->conn_wait_comp);
4211 		wait_for_completion(&conn->conn_post_wait_comp);
4212 		spin_lock_bh(&conn->state_lock);
4213 	}
4214 
4215 	/*
4216 	 * If connection reinstatement is being performed on this connection
4217 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4218 	 * connection wait rcfr semaphore that is being blocked on
4219 	 * an iscsit_connection_reinstatement_rcfr().
4220 	 */
4221 	if (atomic_read(&conn->connection_wait_rcfr)) {
4222 		spin_unlock_bh(&conn->state_lock);
4223 		complete(&conn->conn_wait_rcfr_comp);
4224 		wait_for_completion(&conn->conn_post_wait_comp);
4225 		spin_lock_bh(&conn->state_lock);
4226 	}
4227 	atomic_set(&conn->connection_reinstatement, 1);
4228 	spin_unlock_bh(&conn->state_lock);
4229 
4230 	/*
4231 	 * If any other processes are accessing this connection pointer we
4232 	 * must wait until they have completed.
4233 	 */
4234 	iscsit_check_conn_usage_count(conn);
4235 
4236 	ahash_request_free(conn->conn_tx_hash);
4237 	if (conn->conn_rx_hash) {
4238 		struct crypto_ahash *tfm;
4239 
4240 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4241 		ahash_request_free(conn->conn_rx_hash);
4242 		crypto_free_ahash(tfm);
4243 	}
4244 
4245 	if (conn->sock)
4246 		sock_release(conn->sock);
4247 
4248 	if (conn->conn_transport->iscsit_free_conn)
4249 		conn->conn_transport->iscsit_free_conn(conn);
4250 
4251 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4252 	conn->conn_state = TARG_CONN_STATE_FREE;
4253 	iscsit_free_conn(conn);
4254 
4255 	spin_lock_bh(&sess->conn_lock);
4256 	atomic_dec(&sess->nconn);
4257 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4258 		" %s\n", atomic_read(&sess->nconn),
4259 		sess->sess_ops->InitiatorName);
4260 	/*
4261 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4262 	 * Session that they all fail.
4263 	 */
4264 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4265 	     !atomic_read(&sess->session_logout))
4266 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4267 
4268 	/*
4269 	 * If this was not the last connection in the session, and we are
4270 	 * performing session reinstatement or falling back to ERL=0, call
4271 	 * iscsit_stop_session() without sleeping to shutdown the other
4272 	 * active connections.
4273 	 */
4274 	if (atomic_read(&sess->nconn)) {
4275 		if (!atomic_read(&sess->session_reinstatement) &&
4276 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4277 			spin_unlock_bh(&sess->conn_lock);
4278 			return 0;
4279 		}
4280 		if (!atomic_read(&sess->session_stop_active)) {
4281 			atomic_set(&sess->session_stop_active, 1);
4282 			spin_unlock_bh(&sess->conn_lock);
4283 			iscsit_stop_session(sess, 0, 0);
4284 			return 0;
4285 		}
4286 		spin_unlock_bh(&sess->conn_lock);
4287 		return 0;
4288 	}
4289 
4290 	/*
4291 	 * If this was the last connection in the session and one of the
4292 	 * following is occurring:
4293 	 *
4294 	 * Session Reinstatement is not being performed, and are falling back
4295 	 * to ERL=0 call iscsit_close_session().
4296 	 *
4297 	 * Session Logout was requested.  iscsit_close_session() will be called
4298 	 * elsewhere.
4299 	 *
4300 	 * Session Continuation is not being performed, start the Time2Retain
4301 	 * handler and check if sleep_on_sess_wait_sem is active.
4302 	 */
4303 	if (!atomic_read(&sess->session_reinstatement) &&
4304 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4305 		spin_unlock_bh(&sess->conn_lock);
4306 		iscsit_close_session(sess);
4307 
4308 		return 0;
4309 	} else if (atomic_read(&sess->session_logout)) {
4310 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4311 		sess->session_state = TARG_SESS_STATE_FREE;
4312 		spin_unlock_bh(&sess->conn_lock);
4313 
4314 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4315 			complete(&sess->session_wait_comp);
4316 
4317 		return 0;
4318 	} else {
4319 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4320 		sess->session_state = TARG_SESS_STATE_FAILED;
4321 
4322 		if (!atomic_read(&sess->session_continuation)) {
4323 			spin_unlock_bh(&sess->conn_lock);
4324 			iscsit_start_time2retain_handler(sess);
4325 		} else
4326 			spin_unlock_bh(&sess->conn_lock);
4327 
4328 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4329 			complete(&sess->session_wait_comp);
4330 
4331 		return 0;
4332 	}
4333 }
4334 
4335 /*
4336  * If the iSCSI Session for the iSCSI Initiator Node exists,
4337  * forcefully shutdown the iSCSI NEXUS.
4338  */
4339 int iscsit_close_session(struct iscsi_session *sess)
4340 {
4341 	struct iscsi_portal_group *tpg = sess->tpg;
4342 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4343 
4344 	if (atomic_read(&sess->nconn)) {
4345 		pr_err("%d connection(s) still exist for iSCSI session"
4346 			" to %s\n", atomic_read(&sess->nconn),
4347 			sess->sess_ops->InitiatorName);
4348 		BUG();
4349 	}
4350 
4351 	spin_lock_bh(&se_tpg->session_lock);
4352 	atomic_set(&sess->session_logout, 1);
4353 	atomic_set(&sess->session_reinstatement, 1);
4354 	iscsit_stop_time2retain_timer(sess);
4355 	spin_unlock_bh(&se_tpg->session_lock);
4356 
4357 	/*
4358 	 * transport_deregister_session_configfs() will clear the
4359 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4360 	 * can be setting it again with __transport_register_session() in
4361 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4362 	 * completes in iscsi_np context.
4363 	 */
4364 	transport_deregister_session_configfs(sess->se_sess);
4365 
4366 	/*
4367 	 * If any other processes are accessing this session pointer we must
4368 	 * wait until they have completed.  If we are in an interrupt (the
4369 	 * time2retain handler) and contain and active session usage count we
4370 	 * restart the timer and exit.
4371 	 */
4372 	if (!in_interrupt()) {
4373 		if (iscsit_check_session_usage_count(sess) == 1)
4374 			iscsit_stop_session(sess, 1, 1);
4375 	} else {
4376 		if (iscsit_check_session_usage_count(sess) == 2) {
4377 			atomic_set(&sess->session_logout, 0);
4378 			iscsit_start_time2retain_handler(sess);
4379 			return 0;
4380 		}
4381 	}
4382 
4383 	transport_deregister_session(sess->se_sess);
4384 
4385 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4386 		iscsit_free_connection_recovery_entries(sess);
4387 
4388 	iscsit_free_all_ooo_cmdsns(sess);
4389 
4390 	spin_lock_bh(&se_tpg->session_lock);
4391 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4392 	sess->session_state = TARG_SESS_STATE_FREE;
4393 	pr_debug("Released iSCSI session from node: %s\n",
4394 			sess->sess_ops->InitiatorName);
4395 	tpg->nsessions--;
4396 	if (tpg->tpg_tiqn)
4397 		tpg->tpg_tiqn->tiqn_nsessions--;
4398 
4399 	pr_debug("Decremented number of active iSCSI Sessions on"
4400 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4401 
4402 	ida_free(&sess_ida, sess->session_index);
4403 	kfree(sess->sess_ops);
4404 	sess->sess_ops = NULL;
4405 	spin_unlock_bh(&se_tpg->session_lock);
4406 
4407 	kfree(sess);
4408 	return 0;
4409 }
4410 
4411 static void iscsit_logout_post_handler_closesession(
4412 	struct iscsi_conn *conn)
4413 {
4414 	struct iscsi_session *sess = conn->sess;
4415 	int sleep = 1;
4416 	/*
4417 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4418 	 * context during session logout, so clear tx_thread_active and
4419 	 * sleep if iscsit_close_connection() has not already occured.
4420 	 *
4421 	 * Since iser-target invokes this logic from it's own workqueue,
4422 	 * always sleep waiting for RX/TX thread shutdown to complete
4423 	 * within iscsit_close_connection().
4424 	 */
4425 	if (!conn->conn_transport->rdma_shutdown) {
4426 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4427 		if (!sleep)
4428 			return;
4429 	}
4430 
4431 	atomic_set(&conn->conn_logout_remove, 0);
4432 	complete(&conn->conn_logout_comp);
4433 
4434 	iscsit_dec_conn_usage_count(conn);
4435 	iscsit_stop_session(sess, sleep, sleep);
4436 	iscsit_dec_session_usage_count(sess);
4437 	iscsit_close_session(sess);
4438 }
4439 
4440 static void iscsit_logout_post_handler_samecid(
4441 	struct iscsi_conn *conn)
4442 {
4443 	int sleep = 1;
4444 
4445 	if (!conn->conn_transport->rdma_shutdown) {
4446 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4447 		if (!sleep)
4448 			return;
4449 	}
4450 
4451 	atomic_set(&conn->conn_logout_remove, 0);
4452 	complete(&conn->conn_logout_comp);
4453 
4454 	iscsit_cause_connection_reinstatement(conn, sleep);
4455 	iscsit_dec_conn_usage_count(conn);
4456 }
4457 
4458 static void iscsit_logout_post_handler_diffcid(
4459 	struct iscsi_conn *conn,
4460 	u16 cid)
4461 {
4462 	struct iscsi_conn *l_conn;
4463 	struct iscsi_session *sess = conn->sess;
4464 	bool conn_found = false;
4465 
4466 	if (!sess)
4467 		return;
4468 
4469 	spin_lock_bh(&sess->conn_lock);
4470 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4471 		if (l_conn->cid == cid) {
4472 			iscsit_inc_conn_usage_count(l_conn);
4473 			conn_found = true;
4474 			break;
4475 		}
4476 	}
4477 	spin_unlock_bh(&sess->conn_lock);
4478 
4479 	if (!conn_found)
4480 		return;
4481 
4482 	if (l_conn->sock)
4483 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4484 
4485 	spin_lock_bh(&l_conn->state_lock);
4486 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4487 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4488 	spin_unlock_bh(&l_conn->state_lock);
4489 
4490 	iscsit_cause_connection_reinstatement(l_conn, 1);
4491 	iscsit_dec_conn_usage_count(l_conn);
4492 }
4493 
4494 /*
4495  *	Return of 0 causes the TX thread to restart.
4496  */
4497 int iscsit_logout_post_handler(
4498 	struct iscsi_cmd *cmd,
4499 	struct iscsi_conn *conn)
4500 {
4501 	int ret = 0;
4502 
4503 	switch (cmd->logout_reason) {
4504 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4505 		switch (cmd->logout_response) {
4506 		case ISCSI_LOGOUT_SUCCESS:
4507 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4508 		default:
4509 			iscsit_logout_post_handler_closesession(conn);
4510 			break;
4511 		}
4512 		ret = 0;
4513 		break;
4514 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4515 		if (conn->cid == cmd->logout_cid) {
4516 			switch (cmd->logout_response) {
4517 			case ISCSI_LOGOUT_SUCCESS:
4518 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4519 			default:
4520 				iscsit_logout_post_handler_samecid(conn);
4521 				break;
4522 			}
4523 			ret = 0;
4524 		} else {
4525 			switch (cmd->logout_response) {
4526 			case ISCSI_LOGOUT_SUCCESS:
4527 				iscsit_logout_post_handler_diffcid(conn,
4528 					cmd->logout_cid);
4529 				break;
4530 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4531 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4532 			default:
4533 				break;
4534 			}
4535 			ret = 1;
4536 		}
4537 		break;
4538 	case ISCSI_LOGOUT_REASON_RECOVERY:
4539 		switch (cmd->logout_response) {
4540 		case ISCSI_LOGOUT_SUCCESS:
4541 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4542 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4543 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4544 		default:
4545 			break;
4546 		}
4547 		ret = 1;
4548 		break;
4549 	default:
4550 		break;
4551 
4552 	}
4553 	return ret;
4554 }
4555 EXPORT_SYMBOL(iscsit_logout_post_handler);
4556 
4557 void iscsit_fail_session(struct iscsi_session *sess)
4558 {
4559 	struct iscsi_conn *conn;
4560 
4561 	spin_lock_bh(&sess->conn_lock);
4562 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4563 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4564 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4565 	}
4566 	spin_unlock_bh(&sess->conn_lock);
4567 
4568 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4569 	sess->session_state = TARG_SESS_STATE_FAILED;
4570 }
4571 
4572 int iscsit_free_session(struct iscsi_session *sess)
4573 {
4574 	u16 conn_count = atomic_read(&sess->nconn);
4575 	struct iscsi_conn *conn, *conn_tmp = NULL;
4576 	int is_last;
4577 
4578 	spin_lock_bh(&sess->conn_lock);
4579 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4580 
4581 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4582 			conn_list) {
4583 		if (conn_count == 0)
4584 			break;
4585 
4586 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4587 			is_last = 1;
4588 		} else {
4589 			iscsit_inc_conn_usage_count(conn_tmp);
4590 			is_last = 0;
4591 		}
4592 		iscsit_inc_conn_usage_count(conn);
4593 
4594 		spin_unlock_bh(&sess->conn_lock);
4595 		iscsit_cause_connection_reinstatement(conn, 1);
4596 		spin_lock_bh(&sess->conn_lock);
4597 
4598 		iscsit_dec_conn_usage_count(conn);
4599 		if (is_last == 0)
4600 			iscsit_dec_conn_usage_count(conn_tmp);
4601 
4602 		conn_count--;
4603 	}
4604 
4605 	if (atomic_read(&sess->nconn)) {
4606 		spin_unlock_bh(&sess->conn_lock);
4607 		wait_for_completion(&sess->session_wait_comp);
4608 	} else
4609 		spin_unlock_bh(&sess->conn_lock);
4610 
4611 	iscsit_close_session(sess);
4612 	return 0;
4613 }
4614 
4615 void iscsit_stop_session(
4616 	struct iscsi_session *sess,
4617 	int session_sleep,
4618 	int connection_sleep)
4619 {
4620 	u16 conn_count = atomic_read(&sess->nconn);
4621 	struct iscsi_conn *conn, *conn_tmp = NULL;
4622 	int is_last;
4623 
4624 	spin_lock_bh(&sess->conn_lock);
4625 	if (session_sleep)
4626 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4627 
4628 	if (connection_sleep) {
4629 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4630 				conn_list) {
4631 			if (conn_count == 0)
4632 				break;
4633 
4634 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4635 				is_last = 1;
4636 			} else {
4637 				iscsit_inc_conn_usage_count(conn_tmp);
4638 				is_last = 0;
4639 			}
4640 			iscsit_inc_conn_usage_count(conn);
4641 
4642 			spin_unlock_bh(&sess->conn_lock);
4643 			iscsit_cause_connection_reinstatement(conn, 1);
4644 			spin_lock_bh(&sess->conn_lock);
4645 
4646 			iscsit_dec_conn_usage_count(conn);
4647 			if (is_last == 0)
4648 				iscsit_dec_conn_usage_count(conn_tmp);
4649 			conn_count--;
4650 		}
4651 	} else {
4652 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4653 			iscsit_cause_connection_reinstatement(conn, 0);
4654 	}
4655 
4656 	if (session_sleep && atomic_read(&sess->nconn)) {
4657 		spin_unlock_bh(&sess->conn_lock);
4658 		wait_for_completion(&sess->session_wait_comp);
4659 	} else
4660 		spin_unlock_bh(&sess->conn_lock);
4661 }
4662 
4663 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4664 {
4665 	struct iscsi_session *sess;
4666 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4667 	struct se_session *se_sess, *se_sess_tmp;
4668 	LIST_HEAD(free_list);
4669 	int session_count = 0;
4670 
4671 	spin_lock_bh(&se_tpg->session_lock);
4672 	if (tpg->nsessions && !force) {
4673 		spin_unlock_bh(&se_tpg->session_lock);
4674 		return -1;
4675 	}
4676 
4677 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4678 			sess_list) {
4679 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4680 
4681 		spin_lock(&sess->conn_lock);
4682 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4683 		    atomic_read(&sess->session_logout) ||
4684 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4685 			spin_unlock(&sess->conn_lock);
4686 			continue;
4687 		}
4688 		atomic_set(&sess->session_reinstatement, 1);
4689 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4690 		spin_unlock(&sess->conn_lock);
4691 
4692 		list_move_tail(&se_sess->sess_list, &free_list);
4693 	}
4694 	spin_unlock_bh(&se_tpg->session_lock);
4695 
4696 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4697 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4698 
4699 		iscsit_free_session(sess);
4700 		session_count++;
4701 	}
4702 
4703 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4704 			" Group: %hu\n", session_count, tpg->tpgt);
4705 	return 0;
4706 }
4707 
4708 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4709 MODULE_VERSION("4.1.x");
4710 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4711 MODULE_LICENSE("GPL");
4712 
4713 module_init(iscsi_target_init_module);
4714 module_exit(iscsi_target_cleanup_module);
4715