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 		list_del_init(&cmd->i_conn_node);
488 	spin_unlock_bh(&conn->cmd_lock);
489 
490 	__iscsit_free_cmd(cmd, true);
491 }
492 EXPORT_SYMBOL(iscsit_aborted_task);
493 
494 static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
495 				      u32, u32, const void *, void *);
496 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *);
497 
498 static int
499 iscsit_xmit_nondatain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
500 			  const void *data_buf, u32 data_buf_len)
501 {
502 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
503 	struct kvec *iov;
504 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
505 	int ret;
506 
507 	iov = &cmd->iov_misc[0];
508 	iov[niov].iov_base	= cmd->pdu;
509 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
510 
511 	if (conn->conn_ops->HeaderDigest) {
512 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
513 
514 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
515 					  ISCSI_HDR_LEN, 0, NULL,
516 					  header_digest);
517 
518 		iov[0].iov_len += ISCSI_CRC_LEN;
519 		tx_size += ISCSI_CRC_LEN;
520 		pr_debug("Attaching CRC32C HeaderDigest"
521 			 " to opcode 0x%x 0x%08x\n",
522 			 hdr->opcode, *header_digest);
523 	}
524 
525 	if (data_buf_len) {
526 		u32 padding = ((-data_buf_len) & 3);
527 
528 		iov[niov].iov_base	= (void *)data_buf;
529 		iov[niov++].iov_len	= data_buf_len;
530 		tx_size += data_buf_len;
531 
532 		if (padding != 0) {
533 			iov[niov].iov_base = &cmd->pad_bytes;
534 			iov[niov++].iov_len = padding;
535 			tx_size += padding;
536 			pr_debug("Attaching %u additional"
537 				 " padding bytes.\n", padding);
538 		}
539 
540 		if (conn->conn_ops->DataDigest) {
541 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
542 						  data_buf, data_buf_len,
543 						  padding, &cmd->pad_bytes,
544 						  &cmd->data_crc);
545 
546 			iov[niov].iov_base = &cmd->data_crc;
547 			iov[niov++].iov_len = ISCSI_CRC_LEN;
548 			tx_size += ISCSI_CRC_LEN;
549 			pr_debug("Attached DataDigest for %u"
550 				 " bytes opcode 0x%x, CRC 0x%08x\n",
551 				 data_buf_len, hdr->opcode, cmd->data_crc);
552 		}
553 	}
554 
555 	cmd->iov_misc_count = niov;
556 	cmd->tx_size = tx_size;
557 
558 	ret = iscsit_send_tx_data(cmd, conn, 1);
559 	if (ret < 0) {
560 		iscsit_tx_thread_wait_for_tcp(conn);
561 		return ret;
562 	}
563 
564 	return 0;
565 }
566 
567 static int iscsit_map_iovec(struct iscsi_cmd *cmd, struct kvec *iov, int nvec,
568 			    u32 data_offset, u32 data_length);
569 static void iscsit_unmap_iovec(struct iscsi_cmd *);
570 static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsi_cmd *,
571 				    u32, u32, u32, u8 *);
572 static int
573 iscsit_xmit_datain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
574 		       const struct iscsi_datain *datain)
575 {
576 	struct kvec *iov;
577 	u32 iov_count = 0, tx_size = 0;
578 	int ret, iov_ret;
579 
580 	iov = &cmd->iov_data[0];
581 	iov[iov_count].iov_base	= cmd->pdu;
582 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
583 	tx_size += ISCSI_HDR_LEN;
584 
585 	if (conn->conn_ops->HeaderDigest) {
586 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
587 
588 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
589 					  ISCSI_HDR_LEN, 0, NULL,
590 					  header_digest);
591 
592 		iov[0].iov_len += ISCSI_CRC_LEN;
593 		tx_size += ISCSI_CRC_LEN;
594 
595 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
596 			 *header_digest);
597 	}
598 
599 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[iov_count],
600 				   cmd->orig_iov_data_count - (iov_count + 2),
601 				   datain->offset, datain->length);
602 	if (iov_ret < 0)
603 		return -1;
604 
605 	iov_count += iov_ret;
606 	tx_size += datain->length;
607 
608 	cmd->padding = ((-datain->length) & 3);
609 	if (cmd->padding) {
610 		iov[iov_count].iov_base		= cmd->pad_bytes;
611 		iov[iov_count++].iov_len	= cmd->padding;
612 		tx_size += cmd->padding;
613 
614 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
615 	}
616 
617 	if (conn->conn_ops->DataDigest) {
618 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
619 							 cmd, datain->offset,
620 							 datain->length,
621 							 cmd->padding,
622 							 cmd->pad_bytes);
623 
624 		iov[iov_count].iov_base	= &cmd->data_crc;
625 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
626 		tx_size += ISCSI_CRC_LEN;
627 
628 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
629 			 datain->length + cmd->padding, cmd->data_crc);
630 	}
631 
632 	cmd->iov_data_count = iov_count;
633 	cmd->tx_size = tx_size;
634 
635 	ret = iscsit_fe_sendpage_sg(cmd, conn);
636 
637 	iscsit_unmap_iovec(cmd);
638 
639 	if (ret < 0) {
640 		iscsit_tx_thread_wait_for_tcp(conn);
641 		return ret;
642 	}
643 
644 	return 0;
645 }
646 
647 static int iscsit_xmit_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
648 			   struct iscsi_datain_req *dr, const void *buf,
649 			   u32 buf_len)
650 {
651 	if (dr)
652 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
653 	else
654 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
655 }
656 
657 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
658 {
659 	return TARGET_PROT_NORMAL;
660 }
661 
662 static struct iscsit_transport iscsi_target_transport = {
663 	.name			= "iSCSI/TCP",
664 	.transport_type		= ISCSI_TCP,
665 	.rdma_shutdown		= false,
666 	.owner			= NULL,
667 	.iscsit_setup_np	= iscsit_setup_np,
668 	.iscsit_accept_np	= iscsit_accept_np,
669 	.iscsit_free_np		= iscsit_free_np,
670 	.iscsit_get_login_rx	= iscsit_get_login_rx,
671 	.iscsit_put_login_tx	= iscsit_put_login_tx,
672 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
673 	.iscsit_immediate_queue	= iscsit_immediate_queue,
674 	.iscsit_response_queue	= iscsit_response_queue,
675 	.iscsit_queue_data_in	= iscsit_queue_rsp,
676 	.iscsit_queue_status	= iscsit_queue_rsp,
677 	.iscsit_aborted_task	= iscsit_aborted_task,
678 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
679 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
680 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
681 };
682 
683 static int __init iscsi_target_init_module(void)
684 {
685 	int ret = 0, size;
686 
687 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
688 	iscsit_global = kzalloc(sizeof(*iscsit_global), GFP_KERNEL);
689 	if (!iscsit_global)
690 		return -1;
691 
692 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
693 	mutex_init(&auth_id_lock);
694 	idr_init(&tiqn_idr);
695 
696 	ret = target_register_template(&iscsi_ops);
697 	if (ret)
698 		goto out;
699 
700 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
701 	iscsit_global->ts_bitmap = vzalloc(size);
702 	if (!iscsit_global->ts_bitmap)
703 		goto configfs_out;
704 
705 	if (!zalloc_cpumask_var(&iscsit_global->allowed_cpumask, GFP_KERNEL)) {
706 		pr_err("Unable to allocate iscsit_global->allowed_cpumask\n");
707 		goto bitmap_out;
708 	}
709 	cpumask_setall(iscsit_global->allowed_cpumask);
710 
711 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
712 			sizeof(struct iscsi_queue_req),
713 			__alignof__(struct iscsi_queue_req), 0, NULL);
714 	if (!lio_qr_cache) {
715 		pr_err("Unable to kmem_cache_create() for"
716 				" lio_qr_cache\n");
717 		goto cpumask_out;
718 	}
719 
720 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
721 			sizeof(struct iscsi_datain_req),
722 			__alignof__(struct iscsi_datain_req), 0, NULL);
723 	if (!lio_dr_cache) {
724 		pr_err("Unable to kmem_cache_create() for"
725 				" lio_dr_cache\n");
726 		goto qr_out;
727 	}
728 
729 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
730 			sizeof(struct iscsi_ooo_cmdsn),
731 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
732 	if (!lio_ooo_cache) {
733 		pr_err("Unable to kmem_cache_create() for"
734 				" lio_ooo_cache\n");
735 		goto dr_out;
736 	}
737 
738 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
739 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
740 			0, NULL);
741 	if (!lio_r2t_cache) {
742 		pr_err("Unable to kmem_cache_create() for"
743 				" lio_r2t_cache\n");
744 		goto ooo_out;
745 	}
746 
747 	iscsit_register_transport(&iscsi_target_transport);
748 
749 	if (iscsit_load_discovery_tpg() < 0)
750 		goto r2t_out;
751 
752 	return ret;
753 r2t_out:
754 	iscsit_unregister_transport(&iscsi_target_transport);
755 	kmem_cache_destroy(lio_r2t_cache);
756 ooo_out:
757 	kmem_cache_destroy(lio_ooo_cache);
758 dr_out:
759 	kmem_cache_destroy(lio_dr_cache);
760 qr_out:
761 	kmem_cache_destroy(lio_qr_cache);
762 cpumask_out:
763 	free_cpumask_var(iscsit_global->allowed_cpumask);
764 bitmap_out:
765 	vfree(iscsit_global->ts_bitmap);
766 configfs_out:
767 	/* XXX: this probably wants it to be it's own unwind step.. */
768 	if (iscsit_global->discovery_tpg)
769 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
770 	target_unregister_template(&iscsi_ops);
771 out:
772 	kfree(iscsit_global);
773 	return -ENOMEM;
774 }
775 
776 static void __exit iscsi_target_cleanup_module(void)
777 {
778 	iscsit_release_discovery_tpg();
779 	iscsit_unregister_transport(&iscsi_target_transport);
780 	kmem_cache_destroy(lio_qr_cache);
781 	kmem_cache_destroy(lio_dr_cache);
782 	kmem_cache_destroy(lio_ooo_cache);
783 	kmem_cache_destroy(lio_r2t_cache);
784 
785 	/*
786 	 * Shutdown discovery sessions and disable discovery TPG
787 	 */
788 	if (iscsit_global->discovery_tpg)
789 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
790 
791 	target_unregister_template(&iscsi_ops);
792 
793 	free_cpumask_var(iscsit_global->allowed_cpumask);
794 	vfree(iscsit_global->ts_bitmap);
795 	kfree(iscsit_global);
796 }
797 
798 int iscsit_add_reject(
799 	struct iscsi_conn *conn,
800 	u8 reason,
801 	unsigned char *buf)
802 {
803 	struct iscsi_cmd *cmd;
804 
805 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
806 	if (!cmd)
807 		return -1;
808 
809 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
810 	cmd->reject_reason = reason;
811 
812 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
813 	if (!cmd->buf_ptr) {
814 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
815 		iscsit_free_cmd(cmd, false);
816 		return -1;
817 	}
818 
819 	spin_lock_bh(&conn->cmd_lock);
820 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
821 	spin_unlock_bh(&conn->cmd_lock);
822 
823 	cmd->i_state = ISTATE_SEND_REJECT;
824 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
825 
826 	return -1;
827 }
828 EXPORT_SYMBOL(iscsit_add_reject);
829 
830 static int iscsit_add_reject_from_cmd(
831 	struct iscsi_cmd *cmd,
832 	u8 reason,
833 	bool add_to_conn,
834 	unsigned char *buf)
835 {
836 	struct iscsi_conn *conn;
837 	const bool do_put = cmd->se_cmd.se_tfo != NULL;
838 
839 	if (!cmd->conn) {
840 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
841 				cmd->init_task_tag);
842 		return -1;
843 	}
844 	conn = cmd->conn;
845 
846 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
847 	cmd->reject_reason = reason;
848 
849 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
850 	if (!cmd->buf_ptr) {
851 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
852 		iscsit_free_cmd(cmd, false);
853 		return -1;
854 	}
855 
856 	if (add_to_conn) {
857 		spin_lock_bh(&conn->cmd_lock);
858 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
859 		spin_unlock_bh(&conn->cmd_lock);
860 	}
861 
862 	cmd->i_state = ISTATE_SEND_REJECT;
863 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
864 	/*
865 	 * Perform the kref_put now if se_cmd has already been setup by
866 	 * scsit_setup_scsi_cmd()
867 	 */
868 	if (do_put) {
869 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
870 		target_put_sess_cmd(&cmd->se_cmd);
871 	}
872 	return -1;
873 }
874 
875 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
876 				 unsigned char *buf)
877 {
878 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
879 }
880 
881 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
882 {
883 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
884 }
885 EXPORT_SYMBOL(iscsit_reject_cmd);
886 
887 /*
888  * Map some portion of the allocated scatterlist to an iovec, suitable for
889  * kernel sockets to copy data in/out.
890  */
891 static int iscsit_map_iovec(struct iscsi_cmd *cmd, struct kvec *iov, int nvec,
892 			    u32 data_offset, u32 data_length)
893 {
894 	u32 i = 0, orig_data_length = data_length;
895 	struct scatterlist *sg;
896 	unsigned int page_off;
897 
898 	/*
899 	 * We know each entry in t_data_sg contains a page.
900 	 */
901 	u32 ent = data_offset / PAGE_SIZE;
902 
903 	if (!data_length)
904 		return 0;
905 
906 	if (ent >= cmd->se_cmd.t_data_nents) {
907 		pr_err("Initial page entry out-of-bounds\n");
908 		goto overflow;
909 	}
910 
911 	sg = &cmd->se_cmd.t_data_sg[ent];
912 	page_off = (data_offset % PAGE_SIZE);
913 
914 	cmd->first_data_sg = sg;
915 	cmd->first_data_sg_off = page_off;
916 
917 	while (data_length) {
918 		u32 cur_len;
919 
920 		if (WARN_ON_ONCE(!sg || i >= nvec))
921 			goto overflow;
922 
923 		cur_len = min_t(u32, data_length, sg->length - page_off);
924 
925 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
926 		iov[i].iov_len = cur_len;
927 
928 		data_length -= cur_len;
929 		page_off = 0;
930 		sg = sg_next(sg);
931 		i++;
932 	}
933 
934 	cmd->kmapped_nents = i;
935 
936 	return i;
937 
938 overflow:
939 	pr_err("offset %d + length %d overflow; %d/%d; sg-list:\n",
940 	       data_offset, orig_data_length, i, nvec);
941 	for_each_sg(cmd->se_cmd.t_data_sg, sg,
942 		    cmd->se_cmd.t_data_nents, i) {
943 		pr_err("[%d] off %d len %d\n",
944 		       i, sg->offset, sg->length);
945 	}
946 	return -1;
947 }
948 
949 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
950 {
951 	u32 i;
952 	struct scatterlist *sg;
953 
954 	sg = cmd->first_data_sg;
955 
956 	for (i = 0; i < cmd->kmapped_nents; i++)
957 		kunmap(sg_page(&sg[i]));
958 }
959 
960 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
961 {
962 	LIST_HEAD(ack_list);
963 	struct iscsi_cmd *cmd, *cmd_p;
964 
965 	conn->exp_statsn = exp_statsn;
966 
967 	if (conn->sess->sess_ops->RDMAExtensions)
968 		return;
969 
970 	spin_lock_bh(&conn->cmd_lock);
971 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
972 		spin_lock(&cmd->istate_lock);
973 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
974 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
975 			cmd->i_state = ISTATE_REMOVE;
976 			spin_unlock(&cmd->istate_lock);
977 			list_move_tail(&cmd->i_conn_node, &ack_list);
978 			continue;
979 		}
980 		spin_unlock(&cmd->istate_lock);
981 	}
982 	spin_unlock_bh(&conn->cmd_lock);
983 
984 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
985 		list_del_init(&cmd->i_conn_node);
986 		iscsit_free_cmd(cmd, false);
987 	}
988 }
989 
990 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
991 {
992 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
993 
994 	iov_count += ISCSI_IOV_DATA_BUFFER;
995 	cmd->iov_data = kcalloc(iov_count, sizeof(*cmd->iov_data), GFP_KERNEL);
996 	if (!cmd->iov_data)
997 		return -ENOMEM;
998 
999 	cmd->orig_iov_data_count = iov_count;
1000 	return 0;
1001 }
1002 
1003 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1004 			  unsigned char *buf)
1005 {
1006 	int data_direction, payload_length;
1007 	struct iscsi_scsi_req *hdr;
1008 	int iscsi_task_attr;
1009 	int sam_task_attr;
1010 
1011 	atomic_long_inc(&conn->sess->cmd_pdus);
1012 
1013 	hdr			= (struct iscsi_scsi_req *) buf;
1014 	payload_length		= ntoh24(hdr->dlength);
1015 
1016 	/* FIXME; Add checks for AdditionalHeaderSegment */
1017 
1018 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1019 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1020 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1021 				" not set. Bad iSCSI Initiator.\n");
1022 		return iscsit_add_reject_cmd(cmd,
1023 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1024 	}
1025 
1026 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1027 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1028 		/*
1029 		 * From RFC-3720 Section 10.3.1:
1030 		 *
1031 		 * "Either or both of R and W MAY be 1 when either the
1032 		 *  Expected Data Transfer Length and/or Bidirectional Read
1033 		 *  Expected Data Transfer Length are 0"
1034 		 *
1035 		 * For this case, go ahead and clear the unnecssary bits
1036 		 * to avoid any confusion with ->data_direction.
1037 		 */
1038 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1039 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1040 
1041 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1042 			" set when Expected Data Transfer Length is 0 for"
1043 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1044 	}
1045 
1046 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1047 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1048 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1049 			" MUST be set if Expected Data Transfer Length is not 0."
1050 			" Bad iSCSI Initiator\n");
1051 		return iscsit_add_reject_cmd(cmd,
1052 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1053 	}
1054 
1055 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1056 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1057 		pr_err("Bidirectional operations not supported!\n");
1058 		return iscsit_add_reject_cmd(cmd,
1059 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1060 	}
1061 
1062 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1063 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1064 				" Scsi Command PDU.\n");
1065 		return iscsit_add_reject_cmd(cmd,
1066 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1067 	}
1068 
1069 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1070 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1071 			" protocol error.\n", payload_length);
1072 		return iscsit_add_reject_cmd(cmd,
1073 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1074 	}
1075 
1076 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1077 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1078 		pr_err("Expected Data Transfer Length and Length of"
1079 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1080 			" bit is not set protocol error\n");
1081 		return iscsit_add_reject_cmd(cmd,
1082 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1083 	}
1084 
1085 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1086 		pr_err("DataSegmentLength: %u is greater than"
1087 			" EDTL: %u, protocol error.\n", payload_length,
1088 				hdr->data_length);
1089 		return iscsit_add_reject_cmd(cmd,
1090 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1091 	}
1092 
1093 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1094 		pr_err("DataSegmentLength: %u is greater than"
1095 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1096 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1097 		return iscsit_add_reject_cmd(cmd,
1098 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1099 	}
1100 
1101 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1102 		pr_err("DataSegmentLength: %u is greater than"
1103 			" FirstBurstLength: %u, protocol error.\n",
1104 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1105 		return iscsit_add_reject_cmd(cmd,
1106 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1107 	}
1108 
1109 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1110 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1111 			  DMA_NONE;
1112 
1113 	cmd->data_direction = data_direction;
1114 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1115 	/*
1116 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1117 	 */
1118 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1119 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1120 		sam_task_attr = TCM_SIMPLE_TAG;
1121 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1122 		sam_task_attr = TCM_ORDERED_TAG;
1123 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1124 		sam_task_attr = TCM_HEAD_TAG;
1125 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1126 		sam_task_attr = TCM_ACA_TAG;
1127 	else {
1128 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1129 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1130 		sam_task_attr = TCM_SIMPLE_TAG;
1131 	}
1132 
1133 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1134 	cmd->i_state		= ISTATE_NEW_CMD;
1135 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1136 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1137 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1138 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1139 	if (cmd->unsolicited_data)
1140 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1141 
1142 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1143 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1144 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1145 	else
1146 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1147 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1148 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1149 	cmd->first_burst_len	= payload_length;
1150 
1151 	if (!conn->sess->sess_ops->RDMAExtensions &&
1152 	     cmd->data_direction == DMA_FROM_DEVICE) {
1153 		struct iscsi_datain_req *dr;
1154 
1155 		dr = iscsit_allocate_datain_req();
1156 		if (!dr)
1157 			return iscsit_add_reject_cmd(cmd,
1158 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1159 
1160 		iscsit_attach_datain_req(cmd, dr);
1161 	}
1162 
1163 	/*
1164 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1165 	 */
1166 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
1167 			 conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1168 			 cmd->data_direction, sam_task_attr,
1169 			 cmd->sense_buffer + 2, scsilun_to_int(&hdr->lun));
1170 
1171 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1172 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1173 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1174 		conn->cid);
1175 
1176 	target_get_sess_cmd(&cmd->se_cmd, true);
1177 
1178 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1179 	cmd->sense_reason = target_cmd_init_cdb(&cmd->se_cmd, hdr->cdb,
1180 						GFP_KERNEL);
1181 
1182 	if (cmd->sense_reason) {
1183 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1184 			return iscsit_add_reject_cmd(cmd,
1185 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1186 		}
1187 
1188 		goto attach_cmd;
1189 	}
1190 
1191 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd);
1192 	if (cmd->sense_reason)
1193 		goto attach_cmd;
1194 
1195 	cmd->sense_reason = target_cmd_parse_cdb(&cmd->se_cmd);
1196 	if (cmd->sense_reason)
1197 		goto attach_cmd;
1198 
1199 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1200 		return iscsit_add_reject_cmd(cmd,
1201 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1202 	}
1203 
1204 attach_cmd:
1205 	spin_lock_bh(&conn->cmd_lock);
1206 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1207 	spin_unlock_bh(&conn->cmd_lock);
1208 	/*
1209 	 * Check if we need to delay processing because of ALUA
1210 	 * Active/NonOptimized primary access state..
1211 	 */
1212 	core_alua_check_nonop_delay(&cmd->se_cmd);
1213 
1214 	return 0;
1215 }
1216 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1217 
1218 void iscsit_set_unsolicited_dataout(struct iscsi_cmd *cmd)
1219 {
1220 	iscsit_set_dataout_sequence_values(cmd);
1221 
1222 	spin_lock_bh(&cmd->dataout_timeout_lock);
1223 	iscsit_start_dataout_timer(cmd, cmd->conn);
1224 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1225 }
1226 EXPORT_SYMBOL(iscsit_set_unsolicited_dataout);
1227 
1228 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1229 			    struct iscsi_scsi_req *hdr)
1230 {
1231 	int cmdsn_ret = 0;
1232 	/*
1233 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1234 	 * the Immediate Bit is not set, and no Immediate
1235 	 * Data is attached.
1236 	 *
1237 	 * A PDU/CmdSN carrying Immediate Data can only
1238 	 * be processed after the DataCRC has passed.
1239 	 * If the DataCRC fails, the CmdSN MUST NOT
1240 	 * be acknowledged. (See below)
1241 	 */
1242 	if (!cmd->immediate_data) {
1243 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1244 					(unsigned char *)hdr, hdr->cmdsn);
1245 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1246 			return -1;
1247 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1248 			target_put_sess_cmd(&cmd->se_cmd);
1249 			return 0;
1250 		}
1251 	}
1252 
1253 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1254 
1255 	/*
1256 	 * If no Immediate Data is attached, it's OK to return now.
1257 	 */
1258 	if (!cmd->immediate_data) {
1259 		if (!cmd->sense_reason && cmd->unsolicited_data)
1260 			iscsit_set_unsolicited_dataout(cmd);
1261 		if (!cmd->sense_reason)
1262 			return 0;
1263 
1264 		target_put_sess_cmd(&cmd->se_cmd);
1265 		return 0;
1266 	}
1267 
1268 	/*
1269 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1270 	 * execution.  These exceptions are processed in CmdSN order using
1271 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1272 	 */
1273 	if (cmd->sense_reason)
1274 		return 1;
1275 	/*
1276 	 * Call directly into transport_generic_new_cmd() to perform
1277 	 * the backend memory allocation.
1278 	 */
1279 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1280 	if (cmd->sense_reason)
1281 		return 1;
1282 
1283 	return 0;
1284 }
1285 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1286 
1287 static int
1288 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1289 			  bool dump_payload)
1290 {
1291 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1292 	int rc;
1293 
1294 	/*
1295 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1296 	 */
1297 	if (dump_payload) {
1298 		u32 length = min(cmd->se_cmd.data_length - cmd->write_data_done,
1299 				 cmd->first_burst_len);
1300 
1301 		pr_debug("Dumping min(%d - %d, %d) = %d bytes of immediate data\n",
1302 			 cmd->se_cmd.data_length, cmd->write_data_done,
1303 			 cmd->first_burst_len, length);
1304 		rc = iscsit_dump_data_payload(cmd->conn, length, 1);
1305 		pr_debug("Finished dumping immediate data\n");
1306 		if (rc < 0)
1307 			immed_ret = IMMEDIATE_DATA_CANNOT_RECOVER;
1308 	} else {
1309 		immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1310 							 cmd->first_burst_len);
1311 	}
1312 
1313 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1314 		/*
1315 		 * A PDU/CmdSN carrying Immediate Data passed
1316 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1317 		 * Immediate Bit is not set.
1318 		 */
1319 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1320 					(unsigned char *)hdr, hdr->cmdsn);
1321 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1322 			return -1;
1323 
1324 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1325 			target_put_sess_cmd(&cmd->se_cmd);
1326 
1327 			return 0;
1328 		} else if (cmd->unsolicited_data)
1329 			iscsit_set_unsolicited_dataout(cmd);
1330 
1331 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1332 		/*
1333 		 * Immediate Data failed DataCRC and ERL>=1,
1334 		 * silently drop this PDU and let the initiator
1335 		 * plug the CmdSN gap.
1336 		 *
1337 		 * FIXME: Send Unsolicited NOPIN with reserved
1338 		 * TTT here to help the initiator figure out
1339 		 * the missing CmdSN, although they should be
1340 		 * intelligent enough to determine the missing
1341 		 * CmdSN and issue a retry to plug the sequence.
1342 		 */
1343 		cmd->i_state = ISTATE_REMOVE;
1344 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1345 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1346 		return -1;
1347 
1348 	return 0;
1349 }
1350 
1351 static int
1352 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1353 			   unsigned char *buf)
1354 {
1355 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1356 	int rc, immed_data;
1357 	bool dump_payload = false;
1358 
1359 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1360 	if (rc < 0)
1361 		return 0;
1362 	/*
1363 	 * Allocation iovecs needed for struct socket operations for
1364 	 * traditional iSCSI block I/O.
1365 	 */
1366 	if (iscsit_allocate_iovecs(cmd) < 0) {
1367 		return iscsit_reject_cmd(cmd,
1368 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1369 	}
1370 	immed_data = cmd->immediate_data;
1371 
1372 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1373 	if (rc < 0)
1374 		return rc;
1375 	else if (rc > 0)
1376 		dump_payload = true;
1377 
1378 	if (!immed_data)
1379 		return 0;
1380 
1381 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1382 }
1383 
1384 static u32 iscsit_do_crypto_hash_sg(
1385 	struct ahash_request *hash,
1386 	struct iscsi_cmd *cmd,
1387 	u32 data_offset,
1388 	u32 data_length,
1389 	u32 padding,
1390 	u8 *pad_bytes)
1391 {
1392 	u32 data_crc;
1393 	struct scatterlist *sg;
1394 	unsigned int page_off;
1395 
1396 	crypto_ahash_init(hash);
1397 
1398 	sg = cmd->first_data_sg;
1399 	page_off = cmd->first_data_sg_off;
1400 
1401 	if (data_length && page_off) {
1402 		struct scatterlist first_sg;
1403 		u32 len = min_t(u32, data_length, sg->length - page_off);
1404 
1405 		sg_init_table(&first_sg, 1);
1406 		sg_set_page(&first_sg, sg_page(sg), len, sg->offset + page_off);
1407 
1408 		ahash_request_set_crypt(hash, &first_sg, NULL, len);
1409 		crypto_ahash_update(hash);
1410 
1411 		data_length -= len;
1412 		sg = sg_next(sg);
1413 	}
1414 
1415 	while (data_length) {
1416 		u32 cur_len = min_t(u32, data_length, sg->length);
1417 
1418 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1419 		crypto_ahash_update(hash);
1420 
1421 		data_length -= cur_len;
1422 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1423 		sg = sg_next(sg);
1424 	}
1425 
1426 	if (padding) {
1427 		struct scatterlist pad_sg;
1428 
1429 		sg_init_one(&pad_sg, pad_bytes, padding);
1430 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1431 					padding);
1432 		crypto_ahash_finup(hash);
1433 	} else {
1434 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1435 		crypto_ahash_final(hash);
1436 	}
1437 
1438 	return data_crc;
1439 }
1440 
1441 static void iscsit_do_crypto_hash_buf(struct ahash_request *hash,
1442 	const void *buf, u32 payload_length, u32 padding,
1443 	const void *pad_bytes, void *data_crc)
1444 {
1445 	struct scatterlist sg[2];
1446 
1447 	sg_init_table(sg, ARRAY_SIZE(sg));
1448 	sg_set_buf(sg, buf, payload_length);
1449 	if (padding)
1450 		sg_set_buf(sg + 1, pad_bytes, padding);
1451 
1452 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1453 
1454 	crypto_ahash_digest(hash);
1455 }
1456 
1457 int
1458 __iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1459 			   struct iscsi_cmd *cmd, u32 payload_length,
1460 			   bool *success)
1461 {
1462 	struct iscsi_data *hdr = buf;
1463 	struct se_cmd *se_cmd;
1464 	int rc;
1465 
1466 	/* iSCSI write */
1467 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1468 
1469 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1470 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1471 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1472 		payload_length, conn->cid);
1473 
1474 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1475 		pr_err("Command ITT: 0x%08x received DataOUT after"
1476 			" last DataOUT received, dumping payload\n",
1477 			cmd->init_task_tag);
1478 		return iscsit_dump_data_payload(conn, payload_length, 1);
1479 	}
1480 
1481 	if (cmd->data_direction != DMA_TO_DEVICE) {
1482 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1483 			" NON-WRITE command.\n", cmd->init_task_tag);
1484 		return iscsit_dump_data_payload(conn, payload_length, 1);
1485 	}
1486 	se_cmd = &cmd->se_cmd;
1487 	iscsit_mod_dataout_timer(cmd);
1488 
1489 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1490 		pr_err("DataOut Offset: %u, Length %u greater than iSCSI Command EDTL %u, protocol error.\n",
1491 		       be32_to_cpu(hdr->offset), payload_length,
1492 		       cmd->se_cmd.data_length);
1493 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1494 	}
1495 
1496 	if (cmd->unsolicited_data) {
1497 		int dump_unsolicited_data = 0;
1498 
1499 		if (conn->sess->sess_ops->InitialR2T) {
1500 			pr_err("Received unexpected unsolicited data"
1501 				" while InitialR2T=Yes, protocol error.\n");
1502 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1503 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1504 			return -1;
1505 		}
1506 		/*
1507 		 * Special case for dealing with Unsolicited DataOUT
1508 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1509 		 * failures;
1510 		 */
1511 
1512 		/* Something's amiss if we're not in WRITE_PENDING state... */
1513 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1514 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1515 			dump_unsolicited_data = 1;
1516 
1517 		if (dump_unsolicited_data) {
1518 			/*
1519 			 * Check if a delayed TASK_ABORTED status needs to
1520 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1521 			 * received with the unsolicited data out.
1522 			 */
1523 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1524 				iscsit_stop_dataout_timer(cmd);
1525 
1526 			return iscsit_dump_data_payload(conn, payload_length, 1);
1527 		}
1528 	} else {
1529 		/*
1530 		 * For the normal solicited data path:
1531 		 *
1532 		 * Check for a delayed TASK_ABORTED status and dump any
1533 		 * incoming data out payload if one exists.  Also, when the
1534 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1535 		 * data out sequence, we decrement outstanding_r2ts.  Once
1536 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1537 		 * TASK_ABORTED status.
1538 		 */
1539 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1540 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL &&
1541 			    --cmd->outstanding_r2ts < 1)
1542 				iscsit_stop_dataout_timer(cmd);
1543 
1544 			return iscsit_dump_data_payload(conn, payload_length, 1);
1545 		}
1546 	}
1547 	/*
1548 	 * Perform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1549 	 * within-command recovery checks before receiving the payload.
1550 	 */
1551 	rc = iscsit_check_pre_dataout(cmd, buf);
1552 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1553 		return 0;
1554 	else if (rc == DATAOUT_CANNOT_RECOVER)
1555 		return -1;
1556 	*success = true;
1557 	return 0;
1558 }
1559 EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
1560 
1561 int
1562 iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1563 			 struct iscsi_cmd **out_cmd)
1564 {
1565 	struct iscsi_data *hdr = buf;
1566 	struct iscsi_cmd *cmd;
1567 	u32 payload_length = ntoh24(hdr->dlength);
1568 	int rc;
1569 	bool success = false;
1570 
1571 	if (!payload_length) {
1572 		pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
1573 		return 0;
1574 	}
1575 
1576 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1577 		pr_err_ratelimited("DataSegmentLength: %u is greater than"
1578 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1579 			conn->conn_ops->MaxXmitDataSegmentLength);
1580 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
1581 	}
1582 
1583 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
1584 	if (!cmd)
1585 		return 0;
1586 
1587 	rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
1588 
1589 	if (success)
1590 		*out_cmd = cmd;
1591 
1592 	return rc;
1593 }
1594 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1595 
1596 static int
1597 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1598 		   struct iscsi_data *hdr)
1599 {
1600 	struct kvec *iov;
1601 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1602 	u32 payload_length;
1603 	int iov_ret, data_crc_failed = 0;
1604 
1605 	payload_length = min_t(u32, cmd->se_cmd.data_length,
1606 			       ntoh24(hdr->dlength));
1607 	rx_size += payload_length;
1608 	iov = &cmd->iov_data[0];
1609 
1610 	iov_ret = iscsit_map_iovec(cmd, iov, cmd->orig_iov_data_count - 2,
1611 				   be32_to_cpu(hdr->offset), payload_length);
1612 	if (iov_ret < 0)
1613 		return -1;
1614 
1615 	iov_count += iov_ret;
1616 
1617 	padding = ((-payload_length) & 3);
1618 	if (padding != 0) {
1619 		iov[iov_count].iov_base	= cmd->pad_bytes;
1620 		iov[iov_count++].iov_len = padding;
1621 		rx_size += padding;
1622 		pr_debug("Receiving %u padding bytes.\n", padding);
1623 	}
1624 
1625 	if (conn->conn_ops->DataDigest) {
1626 		iov[iov_count].iov_base = &checksum;
1627 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1628 		rx_size += ISCSI_CRC_LEN;
1629 	}
1630 
1631 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
1632 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1633 
1634 	iscsit_unmap_iovec(cmd);
1635 
1636 	if (rx_got != rx_size)
1637 		return -1;
1638 
1639 	if (conn->conn_ops->DataDigest) {
1640 		u32 data_crc;
1641 
1642 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1643 						    be32_to_cpu(hdr->offset),
1644 						    payload_length, padding,
1645 						    cmd->pad_bytes);
1646 
1647 		if (checksum != data_crc) {
1648 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1649 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1650 				" does not match computed 0x%08x\n",
1651 				hdr->itt, hdr->offset, payload_length,
1652 				hdr->datasn, checksum, data_crc);
1653 			data_crc_failed = 1;
1654 		} else {
1655 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1656 				" %u bytes of Data Out\n", checksum,
1657 				payload_length);
1658 		}
1659 	}
1660 
1661 	return data_crc_failed;
1662 }
1663 
1664 int
1665 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1666 			     bool data_crc_failed)
1667 {
1668 	struct iscsi_conn *conn = cmd->conn;
1669 	int rc, ooo_cmdsn;
1670 	/*
1671 	 * Increment post receive data and CRC values or perform
1672 	 * within-command recovery.
1673 	 */
1674 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1675 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1676 		return 0;
1677 	else if (rc == DATAOUT_SEND_R2T) {
1678 		iscsit_set_dataout_sequence_values(cmd);
1679 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1680 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1681 		/*
1682 		 * Handle extra special case for out of order
1683 		 * Unsolicited Data Out.
1684 		 */
1685 		spin_lock_bh(&cmd->istate_lock);
1686 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1687 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1688 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1689 		spin_unlock_bh(&cmd->istate_lock);
1690 
1691 		iscsit_stop_dataout_timer(cmd);
1692 		if (ooo_cmdsn)
1693 			return 0;
1694 		target_execute_cmd(&cmd->se_cmd);
1695 		return 0;
1696 	} else /* DATAOUT_CANNOT_RECOVER */
1697 		return -1;
1698 
1699 	return 0;
1700 }
1701 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1702 
1703 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1704 {
1705 	struct iscsi_cmd *cmd = NULL;
1706 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1707 	int rc;
1708 	bool data_crc_failed = false;
1709 
1710 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1711 	if (rc < 0)
1712 		return 0;
1713 	else if (!cmd)
1714 		return 0;
1715 
1716 	rc = iscsit_get_dataout(conn, cmd, hdr);
1717 	if (rc < 0)
1718 		return rc;
1719 	else if (rc > 0)
1720 		data_crc_failed = true;
1721 
1722 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1723 }
1724 
1725 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1726 			 struct iscsi_nopout *hdr)
1727 {
1728 	u32 payload_length = ntoh24(hdr->dlength);
1729 
1730 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1731 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1732 		if (!cmd)
1733 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1734 						 (unsigned char *)hdr);
1735 
1736 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1737 					 (unsigned char *)hdr);
1738 	}
1739 
1740 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1741 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1742 			" not set, protocol error.\n");
1743 		if (!cmd)
1744 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1745 						 (unsigned char *)hdr);
1746 
1747 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1748 					 (unsigned char *)hdr);
1749 	}
1750 
1751 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1752 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1753 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1754 			" error.\n", payload_length,
1755 			conn->conn_ops->MaxXmitDataSegmentLength);
1756 		if (!cmd)
1757 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1758 						 (unsigned char *)hdr);
1759 
1760 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1761 					 (unsigned char *)hdr);
1762 	}
1763 
1764 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1765 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1766 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1767 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1768 		payload_length);
1769 	/*
1770 	 * This is not a response to a Unsolicited NopIN, which means
1771 	 * it can either be a NOPOUT ping request (with a valid ITT),
1772 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1773 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1774 	 * can contain ping data.
1775 	 */
1776 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1777 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1778 		cmd->i_state		= ISTATE_SEND_NOPIN;
1779 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1780 						1 : 0);
1781 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1782 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1783 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1784 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1785 		cmd->data_direction	= DMA_NONE;
1786 	}
1787 
1788 	return 0;
1789 }
1790 EXPORT_SYMBOL(iscsit_setup_nop_out);
1791 
1792 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1793 			   struct iscsi_nopout *hdr)
1794 {
1795 	struct iscsi_cmd *cmd_p = NULL;
1796 	int cmdsn_ret = 0;
1797 	/*
1798 	 * Initiator is expecting a NopIN ping reply..
1799 	 */
1800 	if (hdr->itt != RESERVED_ITT) {
1801 		if (!cmd)
1802 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1803 						(unsigned char *)hdr);
1804 
1805 		spin_lock_bh(&conn->cmd_lock);
1806 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1807 		spin_unlock_bh(&conn->cmd_lock);
1808 
1809 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1810 
1811 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1812 			iscsit_add_cmd_to_response_queue(cmd, conn,
1813 							 cmd->i_state);
1814 			return 0;
1815 		}
1816 
1817 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1818 				(unsigned char *)hdr, hdr->cmdsn);
1819                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1820 			return 0;
1821 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1822 			return -1;
1823 
1824 		return 0;
1825 	}
1826 	/*
1827 	 * This was a response to a unsolicited NOPIN ping.
1828 	 */
1829 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1830 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1831 		if (!cmd_p)
1832 			return -EINVAL;
1833 
1834 		iscsit_stop_nopin_response_timer(conn);
1835 
1836 		cmd_p->i_state = ISTATE_REMOVE;
1837 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1838 
1839 		iscsit_start_nopin_timer(conn);
1840 		return 0;
1841 	}
1842 	/*
1843 	 * Otherwise, initiator is not expecting a NOPIN is response.
1844 	 * Just ignore for now.
1845 	 */
1846 
1847 	if (cmd)
1848 		iscsit_free_cmd(cmd, false);
1849 
1850         return 0;
1851 }
1852 EXPORT_SYMBOL(iscsit_process_nop_out);
1853 
1854 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1855 				 unsigned char *buf)
1856 {
1857 	unsigned char *ping_data = NULL;
1858 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1859 	struct kvec *iov = NULL;
1860 	u32 payload_length = ntoh24(hdr->dlength);
1861 	int ret;
1862 
1863 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1864 	if (ret < 0)
1865 		return 0;
1866 	/*
1867 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1868 	 */
1869 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1870 		u32 checksum, data_crc, padding = 0;
1871 		int niov = 0, rx_got, rx_size = payload_length;
1872 
1873 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1874 		if (!ping_data) {
1875 			ret = -1;
1876 			goto out;
1877 		}
1878 
1879 		iov = &cmd->iov_misc[0];
1880 		iov[niov].iov_base	= ping_data;
1881 		iov[niov++].iov_len	= payload_length;
1882 
1883 		padding = ((-payload_length) & 3);
1884 		if (padding != 0) {
1885 			pr_debug("Receiving %u additional bytes"
1886 				" for padding.\n", padding);
1887 			iov[niov].iov_base	= &cmd->pad_bytes;
1888 			iov[niov++].iov_len	= padding;
1889 			rx_size += padding;
1890 		}
1891 		if (conn->conn_ops->DataDigest) {
1892 			iov[niov].iov_base	= &checksum;
1893 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1894 			rx_size += ISCSI_CRC_LEN;
1895 		}
1896 
1897 		WARN_ON_ONCE(niov > ARRAY_SIZE(cmd->iov_misc));
1898 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1899 		if (rx_got != rx_size) {
1900 			ret = -1;
1901 			goto out;
1902 		}
1903 
1904 		if (conn->conn_ops->DataDigest) {
1905 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, ping_data,
1906 						  payload_length, padding,
1907 						  cmd->pad_bytes, &data_crc);
1908 
1909 			if (checksum != data_crc) {
1910 				pr_err("Ping data CRC32C DataDigest"
1911 				" 0x%08x does not match computed 0x%08x\n",
1912 					checksum, data_crc);
1913 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1914 					pr_err("Unable to recover from"
1915 					" NOPOUT Ping DataCRC failure while in"
1916 						" ERL=0.\n");
1917 					ret = -1;
1918 					goto out;
1919 				} else {
1920 					/*
1921 					 * Silently drop this PDU and let the
1922 					 * initiator plug the CmdSN gap.
1923 					 */
1924 					pr_debug("Dropping NOPOUT"
1925 					" Command CmdSN: 0x%08x due to"
1926 					" DataCRC error.\n", hdr->cmdsn);
1927 					ret = 0;
1928 					goto out;
1929 				}
1930 			} else {
1931 				pr_debug("Got CRC32C DataDigest"
1932 				" 0x%08x for %u bytes of ping data.\n",
1933 					checksum, payload_length);
1934 			}
1935 		}
1936 
1937 		ping_data[payload_length] = '\0';
1938 		/*
1939 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1940 		 */
1941 		cmd->buf_ptr = ping_data;
1942 		cmd->buf_ptr_size = payload_length;
1943 
1944 		pr_debug("Got %u bytes of NOPOUT ping"
1945 			" data.\n", payload_length);
1946 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1947 	}
1948 
1949 	return iscsit_process_nop_out(conn, cmd, hdr);
1950 out:
1951 	if (cmd)
1952 		iscsit_free_cmd(cmd, false);
1953 
1954 	kfree(ping_data);
1955 	return ret;
1956 }
1957 
1958 static enum tcm_tmreq_table iscsit_convert_tmf(u8 iscsi_tmf)
1959 {
1960 	switch (iscsi_tmf) {
1961 	case ISCSI_TM_FUNC_ABORT_TASK:
1962 		return TMR_ABORT_TASK;
1963 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1964 		return TMR_ABORT_TASK_SET;
1965 	case ISCSI_TM_FUNC_CLEAR_ACA:
1966 		return TMR_CLEAR_ACA;
1967 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1968 		return TMR_CLEAR_TASK_SET;
1969 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1970 		return TMR_LUN_RESET;
1971 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1972 		return TMR_TARGET_WARM_RESET;
1973 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1974 		return TMR_TARGET_COLD_RESET;
1975 	default:
1976 		return TMR_UNKNOWN;
1977 	}
1978 }
1979 
1980 int
1981 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1982 			   unsigned char *buf)
1983 {
1984 	struct se_tmr_req *se_tmr;
1985 	struct iscsi_tmr_req *tmr_req;
1986 	struct iscsi_tm *hdr;
1987 	int out_of_order_cmdsn = 0, ret;
1988 	u8 function, tcm_function = TMR_UNKNOWN;
1989 
1990 	hdr			= (struct iscsi_tm *) buf;
1991 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1992 	function = hdr->flags;
1993 
1994 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1995 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1996 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1997 		hdr->rtt, hdr->refcmdsn, conn->cid);
1998 
1999 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
2000 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2001 	     hdr->rtt != RESERVED_ITT)) {
2002 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
2003 		hdr->rtt = RESERVED_ITT;
2004 	}
2005 
2006 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
2007 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2008 		pr_err("Task Management Request TASK_REASSIGN not"
2009 			" issued as immediate command, bad iSCSI Initiator"
2010 				"implementation\n");
2011 		return iscsit_add_reject_cmd(cmd,
2012 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
2013 	}
2014 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
2015 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
2016 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
2017 
2018 	cmd->data_direction = DMA_NONE;
2019 	cmd->tmr_req = kzalloc(sizeof(*cmd->tmr_req), GFP_KERNEL);
2020 	if (!cmd->tmr_req) {
2021 		return iscsit_add_reject_cmd(cmd,
2022 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
2023 					     buf);
2024 	}
2025 
2026 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
2027 			  conn->sess->se_sess, 0, DMA_NONE,
2028 			  TCM_SIMPLE_TAG, cmd->sense_buffer + 2,
2029 			  scsilun_to_int(&hdr->lun));
2030 
2031 	target_get_sess_cmd(&cmd->se_cmd, true);
2032 
2033 	/*
2034 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
2035 	 * LIO-Target $FABRIC_MOD
2036 	 */
2037 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2038 		tcm_function = iscsit_convert_tmf(function);
2039 		if (tcm_function == TMR_UNKNOWN) {
2040 			pr_err("Unknown iSCSI TMR Function:"
2041 			       " 0x%02x\n", function);
2042 			return iscsit_add_reject_cmd(cmd,
2043 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2044 		}
2045 	}
2046 	ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
2047 				 GFP_KERNEL);
2048 	if (ret < 0)
2049 		return iscsit_add_reject_cmd(cmd,
2050 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2051 
2052 	cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2053 
2054 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2055 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2056 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2057 	cmd->init_task_tag	= hdr->itt;
2058 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2059 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2060 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2061 	se_tmr			= cmd->se_cmd.se_tmr_req;
2062 	tmr_req			= cmd->tmr_req;
2063 	/*
2064 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2065 	 */
2066 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2067 		ret = transport_lookup_tmr_lun(&cmd->se_cmd);
2068 		if (ret < 0) {
2069 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2070 			goto attach;
2071 		}
2072 	}
2073 
2074 	switch (function) {
2075 	case ISCSI_TM_FUNC_ABORT_TASK:
2076 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2077 		if (se_tmr->response)
2078 			goto attach;
2079 		break;
2080 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2081 	case ISCSI_TM_FUNC_CLEAR_ACA:
2082 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2083 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2084 		break;
2085 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2086 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2087 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2088 			goto attach;
2089 		}
2090 		break;
2091 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2092 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2093 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2094 			goto attach;
2095 		}
2096 		break;
2097 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2098 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2099 		/*
2100 		 * Perform sanity checks on the ExpDataSN only if the
2101 		 * TASK_REASSIGN was successful.
2102 		 */
2103 		if (se_tmr->response)
2104 			break;
2105 
2106 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2107 			return iscsit_add_reject_cmd(cmd,
2108 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2109 		break;
2110 	default:
2111 		pr_err("Unknown TMR function: 0x%02x, protocol"
2112 			" error.\n", function);
2113 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2114 		goto attach;
2115 	}
2116 
2117 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2118 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2119 		se_tmr->call_transport = 1;
2120 attach:
2121 	spin_lock_bh(&conn->cmd_lock);
2122 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2123 	spin_unlock_bh(&conn->cmd_lock);
2124 
2125 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2126 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2127 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP) {
2128 			out_of_order_cmdsn = 1;
2129 		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2130 			target_put_sess_cmd(&cmd->se_cmd);
2131 			return 0;
2132 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2133 			return -1;
2134 		}
2135 	}
2136 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2137 
2138 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2139 		return 0;
2140 	/*
2141 	 * Found the referenced task, send to transport for processing.
2142 	 */
2143 	if (se_tmr->call_transport)
2144 		return transport_generic_handle_tmr(&cmd->se_cmd);
2145 
2146 	/*
2147 	 * Could not find the referenced LUN, task, or Task Management
2148 	 * command not authorized or supported.  Change state and
2149 	 * let the tx_thread send the response.
2150 	 *
2151 	 * For connection recovery, this is also the default action for
2152 	 * TMR TASK_REASSIGN.
2153 	 */
2154 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2155 	target_put_sess_cmd(&cmd->se_cmd);
2156 	return 0;
2157 }
2158 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2159 
2160 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2161 int
2162 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2163 		      struct iscsi_text *hdr)
2164 {
2165 	u32 payload_length = ntoh24(hdr->dlength);
2166 
2167 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2168 		pr_err("Unable to accept text parameter length: %u"
2169 			"greater than MaxXmitDataSegmentLength %u.\n",
2170 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2171 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2172 					 (unsigned char *)hdr);
2173 	}
2174 
2175 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2176 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2177 		pr_err("Multi sequence text commands currently not supported\n");
2178 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2179 					(unsigned char *)hdr);
2180 	}
2181 
2182 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2183 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2184 		hdr->exp_statsn, payload_length);
2185 
2186 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2187 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2188 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2189 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2190 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2191 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2192 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2193 	cmd->data_direction	= DMA_NONE;
2194 	kfree(cmd->text_in_ptr);
2195 	cmd->text_in_ptr	= NULL;
2196 
2197 	return 0;
2198 }
2199 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2200 
2201 int
2202 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2203 			struct iscsi_text *hdr)
2204 {
2205 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2206 	int cmdsn_ret;
2207 
2208 	if (!text_in) {
2209 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2210 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2211 			pr_err("Unable to locate text_in buffer for sendtargets"
2212 			       " discovery\n");
2213 			goto reject;
2214 		}
2215 		goto empty_sendtargets;
2216 	}
2217 	if (strncmp("SendTargets=", text_in, 12) != 0) {
2218 		pr_err("Received Text Data that is not"
2219 			" SendTargets, cannot continue.\n");
2220 		goto reject;
2221 	}
2222 	/* '=' confirmed in strncmp */
2223 	text_ptr = strchr(text_in, '=');
2224 	BUG_ON(!text_ptr);
2225 	if (!strncmp("=All", text_ptr, 5)) {
2226 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2227 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2228 		   !strncmp("=eui.", text_ptr, 5)) {
2229 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2230 	} else {
2231 		pr_err("Unable to locate valid SendTargets%s value\n",
2232 		       text_ptr);
2233 		goto reject;
2234 	}
2235 
2236 	spin_lock_bh(&conn->cmd_lock);
2237 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2238 	spin_unlock_bh(&conn->cmd_lock);
2239 
2240 empty_sendtargets:
2241 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2242 
2243 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2244 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2245 				(unsigned char *)hdr, hdr->cmdsn);
2246 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2247 			return -1;
2248 
2249 		return 0;
2250 	}
2251 
2252 	return iscsit_execute_cmd(cmd, 0);
2253 
2254 reject:
2255 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2256 				 (unsigned char *)hdr);
2257 }
2258 EXPORT_SYMBOL(iscsit_process_text_cmd);
2259 
2260 static int
2261 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2262 		       unsigned char *buf)
2263 {
2264 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2265 	char *text_in = NULL;
2266 	u32 payload_length = ntoh24(hdr->dlength);
2267 	int rx_size, rc;
2268 
2269 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2270 	if (rc < 0)
2271 		return 0;
2272 
2273 	rx_size = payload_length;
2274 	if (payload_length) {
2275 		u32 checksum = 0, data_crc = 0;
2276 		u32 padding = 0;
2277 		int niov = 0, rx_got;
2278 		struct kvec iov[2];
2279 
2280 		rx_size = ALIGN(payload_length, 4);
2281 		text_in = kzalloc(rx_size, GFP_KERNEL);
2282 		if (!text_in)
2283 			goto reject;
2284 
2285 		cmd->text_in_ptr = text_in;
2286 
2287 		memset(iov, 0, sizeof(iov));
2288 		iov[niov].iov_base	= text_in;
2289 		iov[niov++].iov_len	= rx_size;
2290 
2291 		padding = rx_size - payload_length;
2292 		if (padding)
2293 			pr_debug("Receiving %u additional bytes"
2294 					" for padding.\n", padding);
2295 		if (conn->conn_ops->DataDigest) {
2296 			iov[niov].iov_base	= &checksum;
2297 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2298 			rx_size += ISCSI_CRC_LEN;
2299 		}
2300 
2301 		WARN_ON_ONCE(niov > ARRAY_SIZE(iov));
2302 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2303 		if (rx_got != rx_size)
2304 			goto reject;
2305 
2306 		if (conn->conn_ops->DataDigest) {
2307 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2308 						  text_in, rx_size, 0, NULL,
2309 						  &data_crc);
2310 
2311 			if (checksum != data_crc) {
2312 				pr_err("Text data CRC32C DataDigest"
2313 					" 0x%08x does not match computed"
2314 					" 0x%08x\n", checksum, data_crc);
2315 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2316 					pr_err("Unable to recover from"
2317 					" Text Data digest failure while in"
2318 						" ERL=0.\n");
2319 					goto reject;
2320 				} else {
2321 					/*
2322 					 * Silently drop this PDU and let the
2323 					 * initiator plug the CmdSN gap.
2324 					 */
2325 					pr_debug("Dropping Text"
2326 					" Command CmdSN: 0x%08x due to"
2327 					" DataCRC error.\n", hdr->cmdsn);
2328 					kfree(text_in);
2329 					return 0;
2330 				}
2331 			} else {
2332 				pr_debug("Got CRC32C DataDigest"
2333 					" 0x%08x for %u bytes of text data.\n",
2334 						checksum, payload_length);
2335 			}
2336 		}
2337 		text_in[payload_length - 1] = '\0';
2338 		pr_debug("Successfully read %d bytes of text"
2339 				" data.\n", payload_length);
2340 	}
2341 
2342 	return iscsit_process_text_cmd(conn, cmd, hdr);
2343 
2344 reject:
2345 	kfree(cmd->text_in_ptr);
2346 	cmd->text_in_ptr = NULL;
2347 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2348 }
2349 
2350 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2351 {
2352 	struct iscsi_conn *conn_p;
2353 	struct iscsi_session *sess = conn->sess;
2354 
2355 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2356 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2357 
2358 	atomic_set(&sess->session_logout, 1);
2359 	atomic_set(&conn->conn_logout_remove, 1);
2360 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2361 
2362 	iscsit_inc_conn_usage_count(conn);
2363 	iscsit_inc_session_usage_count(sess);
2364 
2365 	spin_lock_bh(&sess->conn_lock);
2366 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2367 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2368 			continue;
2369 
2370 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2371 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2372 	}
2373 	spin_unlock_bh(&sess->conn_lock);
2374 
2375 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2376 
2377 	return 0;
2378 }
2379 
2380 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2381 {
2382 	struct iscsi_conn *l_conn;
2383 	struct iscsi_session *sess = conn->sess;
2384 
2385 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2386 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2387 
2388 	/*
2389 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2390 	 * can arrive on a connection with a differing CID.
2391 	 */
2392 	if (conn->cid == cmd->logout_cid) {
2393 		spin_lock_bh(&conn->state_lock);
2394 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2395 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2396 
2397 		atomic_set(&conn->conn_logout_remove, 1);
2398 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2399 		iscsit_inc_conn_usage_count(conn);
2400 
2401 		spin_unlock_bh(&conn->state_lock);
2402 	} else {
2403 		/*
2404 		 * Handle all different cid CLOSECONNECTION requests in
2405 		 * iscsit_logout_post_handler_diffcid() as to give enough
2406 		 * time for any non immediate command's CmdSN to be
2407 		 * acknowledged on the connection in question.
2408 		 *
2409 		 * Here we simply make sure the CID is still around.
2410 		 */
2411 		l_conn = iscsit_get_conn_from_cid(sess,
2412 				cmd->logout_cid);
2413 		if (!l_conn) {
2414 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2415 			iscsit_add_cmd_to_response_queue(cmd, conn,
2416 					cmd->i_state);
2417 			return 0;
2418 		}
2419 
2420 		iscsit_dec_conn_usage_count(l_conn);
2421 	}
2422 
2423 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2424 
2425 	return 0;
2426 }
2427 
2428 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2429 {
2430 	struct iscsi_session *sess = conn->sess;
2431 
2432 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2433 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2434 
2435 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2436 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2437 			" while ERL!=2.\n");
2438 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2439 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2440 		return 0;
2441 	}
2442 
2443 	if (conn->cid == cmd->logout_cid) {
2444 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2445 			" with CID: %hu on CID: %hu, implementation error.\n",
2446 				cmd->logout_cid, conn->cid);
2447 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2448 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2449 		return 0;
2450 	}
2451 
2452 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2453 
2454 	return 0;
2455 }
2456 
2457 int
2458 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2459 			unsigned char *buf)
2460 {
2461 	int cmdsn_ret, logout_remove = 0;
2462 	u8 reason_code = 0;
2463 	struct iscsi_logout *hdr;
2464 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2465 
2466 	hdr			= (struct iscsi_logout *) buf;
2467 	reason_code		= (hdr->flags & 0x7f);
2468 
2469 	if (tiqn) {
2470 		spin_lock(&tiqn->logout_stats.lock);
2471 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2472 			tiqn->logout_stats.normal_logouts++;
2473 		else
2474 			tiqn->logout_stats.abnormal_logouts++;
2475 		spin_unlock(&tiqn->logout_stats.lock);
2476 	}
2477 
2478 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2479 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2480 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2481 		hdr->cid, conn->cid);
2482 
2483 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2484 		pr_err("Received logout request on connection that"
2485 			" is not in logged in state, ignoring request.\n");
2486 		iscsit_free_cmd(cmd, false);
2487 		return 0;
2488 	}
2489 
2490 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2491 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2492 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2493 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2494 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2495 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2496 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2497 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2498 	cmd->logout_reason      = reason_code;
2499 	cmd->data_direction     = DMA_NONE;
2500 
2501 	/*
2502 	 * We need to sleep in these cases (by returning 1) until the Logout
2503 	 * Response gets sent in the tx thread.
2504 	 */
2505 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2506 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2507 	    be16_to_cpu(hdr->cid) == conn->cid))
2508 		logout_remove = 1;
2509 
2510 	spin_lock_bh(&conn->cmd_lock);
2511 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2512 	spin_unlock_bh(&conn->cmd_lock);
2513 
2514 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2515 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2516 
2517 	/*
2518 	 * Immediate commands are executed, well, immediately.
2519 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2520 	 */
2521 	if (cmd->immediate_cmd) {
2522 		int ret = iscsit_execute_cmd(cmd, 0);
2523 
2524 		if (ret < 0)
2525 			return ret;
2526 	} else {
2527 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2528 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2529 			logout_remove = 0;
2530 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2531 			return -1;
2532 	}
2533 
2534 	return logout_remove;
2535 }
2536 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2537 
2538 int iscsit_handle_snack(
2539 	struct iscsi_conn *conn,
2540 	unsigned char *buf)
2541 {
2542 	struct iscsi_snack *hdr;
2543 
2544 	hdr			= (struct iscsi_snack *) buf;
2545 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2546 
2547 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2548 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2549 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2550 			hdr->begrun, hdr->runlength, conn->cid);
2551 
2552 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2553 		pr_err("Initiator sent SNACK request while in"
2554 			" ErrorRecoveryLevel=0.\n");
2555 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2556 					 buf);
2557 	}
2558 	/*
2559 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2560 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2561 	 */
2562 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2563 	case 0:
2564 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2565 			hdr->itt,
2566 			be32_to_cpu(hdr->ttt),
2567 			be32_to_cpu(hdr->begrun),
2568 			be32_to_cpu(hdr->runlength));
2569 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2570 		return iscsit_handle_status_snack(conn, hdr->itt,
2571 			be32_to_cpu(hdr->ttt),
2572 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2573 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2574 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2575 			be32_to_cpu(hdr->begrun),
2576 			be32_to_cpu(hdr->runlength));
2577 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2578 		/* FIXME: Support R-Data SNACK */
2579 		pr_err("R-Data SNACK Not Supported.\n");
2580 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2581 					 buf);
2582 	default:
2583 		pr_err("Unknown SNACK type 0x%02x, protocol"
2584 			" error.\n", hdr->flags & 0x0f);
2585 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2586 					 buf);
2587 	}
2588 
2589 	return 0;
2590 }
2591 EXPORT_SYMBOL(iscsit_handle_snack);
2592 
2593 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2594 {
2595 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2596 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2597 		wait_for_completion_interruptible_timeout(
2598 					&conn->rx_half_close_comp,
2599 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2600 	}
2601 }
2602 
2603 static int iscsit_handle_immediate_data(
2604 	struct iscsi_cmd *cmd,
2605 	struct iscsi_scsi_req *hdr,
2606 	u32 length)
2607 {
2608 	int iov_ret, rx_got = 0, rx_size = 0;
2609 	u32 checksum, iov_count = 0, padding = 0;
2610 	struct iscsi_conn *conn = cmd->conn;
2611 	struct kvec *iov;
2612 	void *overflow_buf = NULL;
2613 
2614 	BUG_ON(cmd->write_data_done > cmd->se_cmd.data_length);
2615 	rx_size = min(cmd->se_cmd.data_length - cmd->write_data_done, length);
2616 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data,
2617 				   cmd->orig_iov_data_count - 2,
2618 				   cmd->write_data_done, rx_size);
2619 	if (iov_ret < 0)
2620 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2621 
2622 	iov_count = iov_ret;
2623 	iov = &cmd->iov_data[0];
2624 	if (rx_size < length) {
2625 		/*
2626 		 * Special case: length of immediate data exceeds the data
2627 		 * buffer size derived from the CDB.
2628 		 */
2629 		overflow_buf = kmalloc(length - rx_size, GFP_KERNEL);
2630 		if (!overflow_buf) {
2631 			iscsit_unmap_iovec(cmd);
2632 			return IMMEDIATE_DATA_CANNOT_RECOVER;
2633 		}
2634 		cmd->overflow_buf = overflow_buf;
2635 		iov[iov_count].iov_base = overflow_buf;
2636 		iov[iov_count].iov_len = length - rx_size;
2637 		iov_count++;
2638 		rx_size = length;
2639 	}
2640 
2641 	padding = ((-length) & 3);
2642 	if (padding != 0) {
2643 		iov[iov_count].iov_base	= cmd->pad_bytes;
2644 		iov[iov_count++].iov_len = padding;
2645 		rx_size += padding;
2646 	}
2647 
2648 	if (conn->conn_ops->DataDigest) {
2649 		iov[iov_count].iov_base		= &checksum;
2650 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2651 		rx_size += ISCSI_CRC_LEN;
2652 	}
2653 
2654 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
2655 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2656 
2657 	iscsit_unmap_iovec(cmd);
2658 
2659 	if (rx_got != rx_size) {
2660 		iscsit_rx_thread_wait_for_tcp(conn);
2661 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2662 	}
2663 
2664 	if (conn->conn_ops->DataDigest) {
2665 		u32 data_crc;
2666 
2667 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2668 						    cmd->write_data_done, length, padding,
2669 						    cmd->pad_bytes);
2670 
2671 		if (checksum != data_crc) {
2672 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2673 				" does not match computed 0x%08x\n", checksum,
2674 				data_crc);
2675 
2676 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2677 				pr_err("Unable to recover from"
2678 					" Immediate Data digest failure while"
2679 					" in ERL=0.\n");
2680 				iscsit_reject_cmd(cmd,
2681 						ISCSI_REASON_DATA_DIGEST_ERROR,
2682 						(unsigned char *)hdr);
2683 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2684 			} else {
2685 				iscsit_reject_cmd(cmd,
2686 						ISCSI_REASON_DATA_DIGEST_ERROR,
2687 						(unsigned char *)hdr);
2688 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2689 			}
2690 		} else {
2691 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2692 				" %u bytes of Immediate Data\n", checksum,
2693 				length);
2694 		}
2695 	}
2696 
2697 	cmd->write_data_done += length;
2698 
2699 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2700 		spin_lock_bh(&cmd->istate_lock);
2701 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2702 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2703 		spin_unlock_bh(&cmd->istate_lock);
2704 	}
2705 
2706 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2707 }
2708 
2709 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2710 	with active network interface */
2711 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2712 {
2713 	struct iscsi_cmd *cmd;
2714 	struct iscsi_conn *conn_p;
2715 	bool found = false;
2716 
2717 	lockdep_assert_held(&conn->sess->conn_lock);
2718 
2719 	/*
2720 	 * Only send a Asynchronous Message on connections whos network
2721 	 * interface is still functional.
2722 	 */
2723 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2724 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2725 			iscsit_inc_conn_usage_count(conn_p);
2726 			found = true;
2727 			break;
2728 		}
2729 	}
2730 
2731 	if (!found)
2732 		return;
2733 
2734 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2735 	if (!cmd) {
2736 		iscsit_dec_conn_usage_count(conn_p);
2737 		return;
2738 	}
2739 
2740 	cmd->logout_cid = conn->cid;
2741 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2742 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2743 
2744 	spin_lock_bh(&conn_p->cmd_lock);
2745 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2746 	spin_unlock_bh(&conn_p->cmd_lock);
2747 
2748 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2749 	iscsit_dec_conn_usage_count(conn_p);
2750 }
2751 
2752 static int iscsit_send_conn_drop_async_message(
2753 	struct iscsi_cmd *cmd,
2754 	struct iscsi_conn *conn)
2755 {
2756 	struct iscsi_async *hdr;
2757 
2758 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2759 
2760 	hdr			= (struct iscsi_async *) cmd->pdu;
2761 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2762 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2763 	cmd->init_task_tag	= RESERVED_ITT;
2764 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2765 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2766 	cmd->stat_sn		= conn->stat_sn++;
2767 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2768 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2769 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2770 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2771 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2772 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2773 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2774 
2775 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2776 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2777 			cmd->logout_cid, conn->cid);
2778 
2779 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2780 }
2781 
2782 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2783 {
2784 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2785 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2786 		wait_for_completion_interruptible_timeout(
2787 					&conn->tx_half_close_comp,
2788 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2789 	}
2790 }
2791 
2792 void
2793 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2794 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2795 			bool set_statsn)
2796 {
2797 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2798 	hdr->flags		= datain->flags;
2799 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2800 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2801 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2802 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2803 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2804 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2805 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2806 		}
2807 	}
2808 	hton24(hdr->dlength, datain->length);
2809 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2810 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2811 				(struct scsi_lun *)&hdr->lun);
2812 	else
2813 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2814 
2815 	hdr->itt		= cmd->init_task_tag;
2816 
2817 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2818 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2819 	else
2820 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2821 	if (set_statsn)
2822 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2823 	else
2824 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2825 
2826 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2827 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2828 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2829 	hdr->offset		= cpu_to_be32(datain->offset);
2830 
2831 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2832 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2833 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2834 		ntohl(hdr->offset), datain->length, conn->cid);
2835 }
2836 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2837 
2838 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2839 {
2840 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2841 	struct iscsi_datain datain;
2842 	struct iscsi_datain_req *dr;
2843 	int eodr = 0, ret;
2844 	bool set_statsn = false;
2845 
2846 	memset(&datain, 0, sizeof(struct iscsi_datain));
2847 	dr = iscsit_get_datain_values(cmd, &datain);
2848 	if (!dr) {
2849 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2850 				cmd->init_task_tag);
2851 		return -1;
2852 	}
2853 	/*
2854 	 * Be paranoid and double check the logic for now.
2855 	 */
2856 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2857 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2858 			" datain.length: %u exceeds cmd->data_length: %u\n",
2859 			cmd->init_task_tag, datain.offset, datain.length,
2860 			cmd->se_cmd.data_length);
2861 		return -1;
2862 	}
2863 
2864 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2865 	/*
2866 	 * Special case for successfully execution w/ both DATAIN
2867 	 * and Sense Data.
2868 	 */
2869 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2870 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2871 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2872 	else {
2873 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2874 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2875 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2876 			cmd->stat_sn = conn->stat_sn++;
2877 			set_statsn = true;
2878 		} else if (dr->dr_complete ==
2879 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2880 			set_statsn = true;
2881 	}
2882 
2883 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2884 
2885 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2886 	if (ret < 0)
2887 		return ret;
2888 
2889 	if (dr->dr_complete) {
2890 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2891 				2 : 1;
2892 		iscsit_free_datain_req(cmd, dr);
2893 	}
2894 
2895 	return eodr;
2896 }
2897 
2898 int
2899 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2900 			struct iscsi_logout_rsp *hdr)
2901 {
2902 	struct iscsi_conn *logout_conn = NULL;
2903 	struct iscsi_conn_recovery *cr = NULL;
2904 	struct iscsi_session *sess = conn->sess;
2905 	/*
2906 	 * The actual shutting down of Sessions and/or Connections
2907 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2908 	 * is done in scsi_logout_post_handler().
2909 	 */
2910 	switch (cmd->logout_reason) {
2911 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2912 		pr_debug("iSCSI session logout successful, setting"
2913 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2914 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2915 		break;
2916 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2917 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2918 			break;
2919 		/*
2920 		 * For CLOSECONNECTION logout requests carrying
2921 		 * a matching logout CID -> local CID, the reference
2922 		 * for the local CID will have been incremented in
2923 		 * iscsi_logout_closeconnection().
2924 		 *
2925 		 * For CLOSECONNECTION logout requests carrying
2926 		 * a different CID than the connection it arrived
2927 		 * on, the connection responding to cmd->logout_cid
2928 		 * is stopped in iscsit_logout_post_handler_diffcid().
2929 		 */
2930 
2931 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2932 			" successful.\n", cmd->logout_cid, conn->cid);
2933 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2934 		break;
2935 	case ISCSI_LOGOUT_REASON_RECOVERY:
2936 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2937 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2938 			break;
2939 		/*
2940 		 * If the connection is still active from our point of view
2941 		 * force connection recovery to occur.
2942 		 */
2943 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2944 				cmd->logout_cid);
2945 		if (logout_conn) {
2946 			iscsit_connection_reinstatement_rcfr(logout_conn);
2947 			iscsit_dec_conn_usage_count(logout_conn);
2948 		}
2949 
2950 		cr = iscsit_get_inactive_connection_recovery_entry(
2951 				conn->sess, cmd->logout_cid);
2952 		if (!cr) {
2953 			pr_err("Unable to locate CID: %hu for"
2954 			" REMOVECONNFORRECOVERY Logout Request.\n",
2955 				cmd->logout_cid);
2956 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2957 			break;
2958 		}
2959 
2960 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2961 
2962 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2963 			" for recovery for CID: %hu on CID: %hu successful.\n",
2964 				cmd->logout_cid, conn->cid);
2965 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2966 		break;
2967 	default:
2968 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2969 				cmd->logout_reason);
2970 		return -1;
2971 	}
2972 
2973 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2974 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2975 	hdr->response		= cmd->logout_response;
2976 	hdr->itt		= cmd->init_task_tag;
2977 	cmd->stat_sn		= conn->stat_sn++;
2978 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2979 
2980 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2981 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2982 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2983 
2984 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2985 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2986 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2987 		cmd->logout_cid, conn->cid);
2988 
2989 	return 0;
2990 }
2991 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2992 
2993 static int
2994 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2995 {
2996 	int rc;
2997 
2998 	rc = iscsit_build_logout_rsp(cmd, conn,
2999 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
3000 	if (rc < 0)
3001 		return rc;
3002 
3003 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3004 }
3005 
3006 void
3007 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3008 		       struct iscsi_nopin *hdr, bool nopout_response)
3009 {
3010 	hdr->opcode		= ISCSI_OP_NOOP_IN;
3011 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3012         hton24(hdr->dlength, cmd->buf_ptr_size);
3013 	if (nopout_response)
3014 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
3015 	hdr->itt		= cmd->init_task_tag;
3016 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
3017 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
3018 				  conn->stat_sn;
3019 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3020 
3021 	if (nopout_response)
3022 		iscsit_increment_maxcmdsn(cmd, conn->sess);
3023 
3024 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3025 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3026 
3027 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
3028 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
3029 		"Solicited" : "Unsolicited", cmd->init_task_tag,
3030 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
3031 }
3032 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
3033 
3034 /*
3035  *	Unsolicited NOPIN, either requesting a response or not.
3036  */
3037 static int iscsit_send_unsolicited_nopin(
3038 	struct iscsi_cmd *cmd,
3039 	struct iscsi_conn *conn,
3040 	int want_response)
3041 {
3042 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3043 	int ret;
3044 
3045 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3046 
3047 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3048 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3049 
3050 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3051 	if (ret < 0)
3052 		return ret;
3053 
3054 	spin_lock_bh(&cmd->istate_lock);
3055 	cmd->i_state = want_response ?
3056 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3057 	spin_unlock_bh(&cmd->istate_lock);
3058 
3059 	return 0;
3060 }
3061 
3062 static int
3063 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3064 {
3065 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3066 
3067 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3068 
3069 	/*
3070 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
3071 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
3072 	 */
3073 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3074 
3075 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3076 						     cmd->buf_ptr,
3077 						     cmd->buf_ptr_size);
3078 }
3079 
3080 static int iscsit_send_r2t(
3081 	struct iscsi_cmd *cmd,
3082 	struct iscsi_conn *conn)
3083 {
3084 	struct iscsi_r2t *r2t;
3085 	struct iscsi_r2t_rsp *hdr;
3086 	int ret;
3087 
3088 	r2t = iscsit_get_r2t_from_list(cmd);
3089 	if (!r2t)
3090 		return -1;
3091 
3092 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3093 	memset(hdr, 0, ISCSI_HDR_LEN);
3094 	hdr->opcode		= ISCSI_OP_R2T;
3095 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3096 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3097 			(struct scsi_lun *)&hdr->lun);
3098 	hdr->itt		= cmd->init_task_tag;
3099 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3100 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3101 	else
3102 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3103 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3104 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3105 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3106 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3107 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3108 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3109 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3110 
3111 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3112 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3113 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3114 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3115 			r2t->offset, r2t->xfer_len, conn->cid);
3116 
3117 	spin_lock_bh(&cmd->r2t_lock);
3118 	r2t->sent_r2t = 1;
3119 	spin_unlock_bh(&cmd->r2t_lock);
3120 
3121 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3122 	if (ret < 0) {
3123 		return ret;
3124 	}
3125 
3126 	spin_lock_bh(&cmd->dataout_timeout_lock);
3127 	iscsit_start_dataout_timer(cmd, conn);
3128 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3129 
3130 	return 0;
3131 }
3132 
3133 /*
3134  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3135  *		connection recovery.
3136  */
3137 int iscsit_build_r2ts_for_cmd(
3138 	struct iscsi_conn *conn,
3139 	struct iscsi_cmd *cmd,
3140 	bool recovery)
3141 {
3142 	int first_r2t = 1;
3143 	u32 offset = 0, xfer_len = 0;
3144 
3145 	spin_lock_bh(&cmd->r2t_lock);
3146 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3147 		spin_unlock_bh(&cmd->r2t_lock);
3148 		return 0;
3149 	}
3150 
3151 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3152 	    !recovery)
3153 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3154 
3155 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3156 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3157 			offset = cmd->r2t_offset;
3158 
3159 			if (first_r2t && recovery) {
3160 				int new_data_end = offset +
3161 					conn->sess->sess_ops->MaxBurstLength -
3162 					cmd->next_burst_len;
3163 
3164 				if (new_data_end > cmd->se_cmd.data_length)
3165 					xfer_len = cmd->se_cmd.data_length - offset;
3166 				else
3167 					xfer_len =
3168 						conn->sess->sess_ops->MaxBurstLength -
3169 						cmd->next_burst_len;
3170 			} else {
3171 				int new_data_end = offset +
3172 					conn->sess->sess_ops->MaxBurstLength;
3173 
3174 				if (new_data_end > cmd->se_cmd.data_length)
3175 					xfer_len = cmd->se_cmd.data_length - offset;
3176 				else
3177 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3178 			}
3179 
3180 			if ((s32)xfer_len < 0) {
3181 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3182 				break;
3183 			}
3184 
3185 			cmd->r2t_offset += xfer_len;
3186 
3187 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3188 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3189 		} else {
3190 			struct iscsi_seq *seq;
3191 
3192 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3193 			if (!seq) {
3194 				spin_unlock_bh(&cmd->r2t_lock);
3195 				return -1;
3196 			}
3197 
3198 			offset = seq->offset;
3199 			xfer_len = seq->xfer_len;
3200 
3201 			if (cmd->seq_send_order == cmd->seq_count)
3202 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3203 		}
3204 		cmd->outstanding_r2ts++;
3205 		first_r2t = 0;
3206 
3207 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3208 			spin_unlock_bh(&cmd->r2t_lock);
3209 			return -1;
3210 		}
3211 
3212 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3213 			break;
3214 	}
3215 	spin_unlock_bh(&cmd->r2t_lock);
3216 
3217 	return 0;
3218 }
3219 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3220 
3221 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3222 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3223 {
3224 	if (inc_stat_sn)
3225 		cmd->stat_sn = conn->stat_sn++;
3226 
3227 	atomic_long_inc(&conn->sess->rsp_pdus);
3228 
3229 	memset(hdr, 0, ISCSI_HDR_LEN);
3230 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3231 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3232 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3233 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3234 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3235 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3236 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3237 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3238 	}
3239 	hdr->response		= cmd->iscsi_response;
3240 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3241 	hdr->itt		= cmd->init_task_tag;
3242 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3243 
3244 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3245 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3246 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3247 
3248 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3249 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3250 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3251 		cmd->se_cmd.scsi_status, conn->cid);
3252 }
3253 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3254 
3255 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3256 {
3257 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3258 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3259 	void *data_buf = NULL;
3260 	u32 padding = 0, data_buf_len = 0;
3261 
3262 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3263 
3264 	/*
3265 	 * Attach SENSE DATA payload to iSCSI Response PDU
3266 	 */
3267 	if (cmd->se_cmd.sense_buffer &&
3268 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3269 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3270 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3271 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3272 
3273 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3274 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3275 		data_buf = cmd->sense_buffer;
3276 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3277 
3278 		if (padding) {
3279 			memset(cmd->sense_buffer +
3280 				cmd->se_cmd.scsi_sense_length, 0, padding);
3281 			pr_debug("Adding %u bytes of padding to"
3282 				" SENSE.\n", padding);
3283 		}
3284 
3285 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3286 				" Response PDU\n",
3287 				cmd->se_cmd.scsi_sense_length);
3288 	}
3289 
3290 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3291 						     data_buf_len);
3292 }
3293 
3294 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3295 {
3296 	switch (se_tmr->response) {
3297 	case TMR_FUNCTION_COMPLETE:
3298 		return ISCSI_TMF_RSP_COMPLETE;
3299 	case TMR_TASK_DOES_NOT_EXIST:
3300 		return ISCSI_TMF_RSP_NO_TASK;
3301 	case TMR_LUN_DOES_NOT_EXIST:
3302 		return ISCSI_TMF_RSP_NO_LUN;
3303 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3304 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3305 	case TMR_FUNCTION_REJECTED:
3306 	default:
3307 		return ISCSI_TMF_RSP_REJECTED;
3308 	}
3309 }
3310 
3311 void
3312 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3313 			  struct iscsi_tm_rsp *hdr)
3314 {
3315 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3316 
3317 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3318 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3319 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3320 	hdr->itt		= cmd->init_task_tag;
3321 	cmd->stat_sn		= conn->stat_sn++;
3322 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3323 
3324 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3325 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3326 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3327 
3328 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3329 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3330 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3331 }
3332 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3333 
3334 static int
3335 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3336 {
3337 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3338 
3339 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3340 
3341 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3342 }
3343 
3344 #define SENDTARGETS_BUF_LIMIT 32768U
3345 
3346 static int
3347 iscsit_build_sendtargets_response(struct iscsi_cmd *cmd,
3348 				  enum iscsit_transport_type network_transport,
3349 				  int skip_bytes, bool *completed)
3350 {
3351 	char *payload = NULL;
3352 	struct iscsi_conn *conn = cmd->conn;
3353 	struct iscsi_portal_group *tpg;
3354 	struct iscsi_tiqn *tiqn;
3355 	struct iscsi_tpg_np *tpg_np;
3356 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3357 	int target_name_printed;
3358 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3359 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3360 	bool active;
3361 
3362 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3363 			 SENDTARGETS_BUF_LIMIT);
3364 
3365 	payload = kzalloc(buffer_len, GFP_KERNEL);
3366 	if (!payload)
3367 		return -ENOMEM;
3368 
3369 	/*
3370 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3371 	 * explicit case..
3372 	 */
3373 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3374 		text_ptr = strchr(text_in, '=');
3375 		if (!text_ptr) {
3376 			pr_err("Unable to locate '=' string in text_in:"
3377 			       " %s\n", text_in);
3378 			kfree(payload);
3379 			return -EINVAL;
3380 		}
3381 		/*
3382 		 * Skip over '=' character..
3383 		 */
3384 		text_ptr += 1;
3385 	}
3386 
3387 	spin_lock(&tiqn_lock);
3388 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3389 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3390 		     strcmp(tiqn->tiqn, text_ptr)) {
3391 			continue;
3392 		}
3393 
3394 		target_name_printed = 0;
3395 
3396 		spin_lock(&tiqn->tiqn_tpg_lock);
3397 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3398 
3399 			/* If demo_mode_discovery=0 and generate_node_acls=0
3400 			 * (demo mode dislabed) do not return
3401 			 * TargetName+TargetAddress unless a NodeACL exists.
3402 			 */
3403 
3404 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3405 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3406 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3407 				cmd->conn->sess->sess_ops->InitiatorName))) {
3408 				continue;
3409 			}
3410 
3411 			spin_lock(&tpg->tpg_state_lock);
3412 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3413 			spin_unlock(&tpg->tpg_state_lock);
3414 
3415 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3416 				continue;
3417 
3418 			spin_lock(&tpg->tpg_np_lock);
3419 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3420 						tpg_np_list) {
3421 				struct iscsi_np *np = tpg_np->tpg_np;
3422 				struct sockaddr_storage *sockaddr;
3423 
3424 				if (np->np_network_transport != network_transport)
3425 					continue;
3426 
3427 				if (!target_name_printed) {
3428 					len = sprintf(buf, "TargetName=%s",
3429 						      tiqn->tiqn);
3430 					len += 1;
3431 
3432 					if ((len + payload_len) > buffer_len) {
3433 						spin_unlock(&tpg->tpg_np_lock);
3434 						spin_unlock(&tiqn->tiqn_tpg_lock);
3435 						end_of_buf = 1;
3436 						goto eob;
3437 					}
3438 
3439 					if (skip_bytes && len <= skip_bytes) {
3440 						skip_bytes -= len;
3441 					} else {
3442 						memcpy(payload + payload_len, buf, len);
3443 						payload_len += len;
3444 						target_name_printed = 1;
3445 						if (len > skip_bytes)
3446 							skip_bytes = 0;
3447 					}
3448 				}
3449 
3450 				if (inet_addr_is_any((struct sockaddr *)&np->np_sockaddr))
3451 					sockaddr = &conn->local_sockaddr;
3452 				else
3453 					sockaddr = &np->np_sockaddr;
3454 
3455 				len = sprintf(buf, "TargetAddress="
3456 					      "%pISpc,%hu",
3457 					      sockaddr,
3458 					      tpg->tpgt);
3459 				len += 1;
3460 
3461 				if ((len + payload_len) > buffer_len) {
3462 					spin_unlock(&tpg->tpg_np_lock);
3463 					spin_unlock(&tiqn->tiqn_tpg_lock);
3464 					end_of_buf = 1;
3465 					goto eob;
3466 				}
3467 
3468 				if (skip_bytes && len <= skip_bytes) {
3469 					skip_bytes -= len;
3470 				} else {
3471 					memcpy(payload + payload_len, buf, len);
3472 					payload_len += len;
3473 					if (len > skip_bytes)
3474 						skip_bytes = 0;
3475 				}
3476 			}
3477 			spin_unlock(&tpg->tpg_np_lock);
3478 		}
3479 		spin_unlock(&tiqn->tiqn_tpg_lock);
3480 eob:
3481 		if (end_of_buf) {
3482 			*completed = false;
3483 			break;
3484 		}
3485 
3486 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3487 			break;
3488 	}
3489 	spin_unlock(&tiqn_lock);
3490 
3491 	cmd->buf_ptr = payload;
3492 
3493 	return payload_len;
3494 }
3495 
3496 int
3497 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3498 		      struct iscsi_text_rsp *hdr,
3499 		      enum iscsit_transport_type network_transport)
3500 {
3501 	int text_length, padding;
3502 	bool completed = true;
3503 
3504 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3505 							cmd->read_data_done,
3506 							&completed);
3507 	if (text_length < 0)
3508 		return text_length;
3509 
3510 	if (completed) {
3511 		hdr->flags = ISCSI_FLAG_CMD_FINAL;
3512 	} else {
3513 		hdr->flags = ISCSI_FLAG_TEXT_CONTINUE;
3514 		cmd->read_data_done += text_length;
3515 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3516 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3517 	}
3518 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3519 	padding = ((-text_length) & 3);
3520 	hton24(hdr->dlength, text_length);
3521 	hdr->itt = cmd->init_task_tag;
3522 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3523 	cmd->stat_sn = conn->stat_sn++;
3524 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3525 
3526 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3527 	/*
3528 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3529 	 * correctly increment MaxCmdSN for each response answering a
3530 	 * non immediate text request with a valid CmdSN.
3531 	 */
3532 	cmd->maxcmdsn_inc = 0;
3533 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3534 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3535 
3536 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3537 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3538 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3539 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3540 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3541 
3542 	return text_length + padding;
3543 }
3544 EXPORT_SYMBOL(iscsit_build_text_rsp);
3545 
3546 static int iscsit_send_text_rsp(
3547 	struct iscsi_cmd *cmd,
3548 	struct iscsi_conn *conn)
3549 {
3550 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3551 	int text_length;
3552 
3553 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3554 				conn->conn_transport->transport_type);
3555 	if (text_length < 0)
3556 		return text_length;
3557 
3558 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3559 						     cmd->buf_ptr,
3560 						     text_length);
3561 }
3562 
3563 void
3564 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3565 		    struct iscsi_reject *hdr)
3566 {
3567 	hdr->opcode		= ISCSI_OP_REJECT;
3568 	hdr->reason		= cmd->reject_reason;
3569 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3570 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3571 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3572 	cmd->stat_sn		= conn->stat_sn++;
3573 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3574 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3575 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3576 
3577 }
3578 EXPORT_SYMBOL(iscsit_build_reject);
3579 
3580 static int iscsit_send_reject(
3581 	struct iscsi_cmd *cmd,
3582 	struct iscsi_conn *conn)
3583 {
3584 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3585 
3586 	iscsit_build_reject(cmd, conn, hdr);
3587 
3588 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3589 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3590 
3591 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3592 						     cmd->buf_ptr,
3593 						     ISCSI_HDR_LEN);
3594 }
3595 
3596 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3597 {
3598 	int ord, cpu;
3599 	cpumask_t conn_allowed_cpumask;
3600 
3601 	cpumask_and(&conn_allowed_cpumask, iscsit_global->allowed_cpumask,
3602 		    cpu_online_mask);
3603 
3604 	/*
3605 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3606 	 * within iscsit_start_kthreads()
3607 	 *
3608 	 * Here we use bitmap_id to determine which CPU that this
3609 	 * iSCSI connection's RX/TX threads will be scheduled to
3610 	 * execute upon.
3611 	 */
3612 	cpumask_clear(conn->conn_cpumask);
3613 	ord = conn->bitmap_id % cpumask_weight(&conn_allowed_cpumask);
3614 	for_each_cpu(cpu, &conn_allowed_cpumask) {
3615 		if (ord-- == 0) {
3616 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3617 			return;
3618 		}
3619 	}
3620 	/*
3621 	 * This should never be reached..
3622 	 */
3623 	dump_stack();
3624 	cpumask_setall(conn->conn_cpumask);
3625 }
3626 
3627 static void iscsit_thread_reschedule(struct iscsi_conn *conn)
3628 {
3629 	/*
3630 	 * If iscsit_global->allowed_cpumask modified, reschedule iSCSI
3631 	 * connection's RX/TX threads update conn->allowed_cpumask.
3632 	 */
3633 	if (!cpumask_equal(iscsit_global->allowed_cpumask,
3634 			   conn->allowed_cpumask)) {
3635 		iscsit_thread_get_cpumask(conn);
3636 		conn->conn_tx_reset_cpumask = 1;
3637 		conn->conn_rx_reset_cpumask = 1;
3638 		cpumask_copy(conn->allowed_cpumask,
3639 			     iscsit_global->allowed_cpumask);
3640 	}
3641 }
3642 
3643 void iscsit_thread_check_cpumask(
3644 	struct iscsi_conn *conn,
3645 	struct task_struct *p,
3646 	int mode)
3647 {
3648 	/*
3649 	 * The TX and RX threads maybe call iscsit_thread_check_cpumask()
3650 	 * at the same time. The RX thread might be faster and return from
3651 	 * iscsit_thread_reschedule() with conn_rx_reset_cpumask set to 0.
3652 	 * Then the TX thread sets it back to 1.
3653 	 * The next time the RX thread loops, it sees conn_rx_reset_cpumask
3654 	 * set to 1 and calls set_cpus_allowed_ptr() again and set it to 0.
3655 	 */
3656 	iscsit_thread_reschedule(conn);
3657 
3658 	/*
3659 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3660 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3661 	 */
3662 	if (mode == 1) {
3663 		if (!conn->conn_tx_reset_cpumask)
3664 			return;
3665 	} else {
3666 		if (!conn->conn_rx_reset_cpumask)
3667 			return;
3668 	}
3669 
3670 	/*
3671 	 * Update the CPU mask for this single kthread so that
3672 	 * both TX and RX kthreads are scheduled to run on the
3673 	 * same CPU.
3674 	 */
3675 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3676 	if (mode == 1)
3677 		conn->conn_tx_reset_cpumask = 0;
3678 	else
3679 		conn->conn_rx_reset_cpumask = 0;
3680 }
3681 EXPORT_SYMBOL(iscsit_thread_check_cpumask);
3682 
3683 int
3684 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3685 {
3686 	int ret;
3687 
3688 	switch (state) {
3689 	case ISTATE_SEND_R2T:
3690 		ret = iscsit_send_r2t(cmd, conn);
3691 		if (ret < 0)
3692 			goto err;
3693 		break;
3694 	case ISTATE_REMOVE:
3695 		spin_lock_bh(&conn->cmd_lock);
3696 		list_del_init(&cmd->i_conn_node);
3697 		spin_unlock_bh(&conn->cmd_lock);
3698 
3699 		iscsit_free_cmd(cmd, false);
3700 		break;
3701 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3702 		iscsit_mod_nopin_response_timer(conn);
3703 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3704 		if (ret < 0)
3705 			goto err;
3706 		break;
3707 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3708 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3709 		if (ret < 0)
3710 			goto err;
3711 		break;
3712 	default:
3713 		pr_err("Unknown Opcode: 0x%02x ITT:"
3714 		       " 0x%08x, i_state: %d on CID: %hu\n",
3715 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3716 		       conn->cid);
3717 		goto err;
3718 	}
3719 
3720 	return 0;
3721 
3722 err:
3723 	return -1;
3724 }
3725 EXPORT_SYMBOL(iscsit_immediate_queue);
3726 
3727 static int
3728 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3729 {
3730 	struct iscsit_transport *t = conn->conn_transport;
3731 	struct iscsi_queue_req *qr;
3732 	struct iscsi_cmd *cmd;
3733 	u8 state;
3734 	int ret;
3735 
3736 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3737 		atomic_set(&conn->check_immediate_queue, 0);
3738 		cmd = qr->cmd;
3739 		state = qr->state;
3740 		kmem_cache_free(lio_qr_cache, qr);
3741 
3742 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3743 		if (ret < 0)
3744 			return ret;
3745 	}
3746 
3747 	return 0;
3748 }
3749 
3750 int
3751 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3752 {
3753 	int ret;
3754 
3755 check_rsp_state:
3756 	switch (state) {
3757 	case ISTATE_SEND_DATAIN:
3758 		ret = iscsit_send_datain(cmd, conn);
3759 		if (ret < 0)
3760 			goto err;
3761 		else if (!ret)
3762 			/* more drs */
3763 			goto check_rsp_state;
3764 		else if (ret == 1) {
3765 			/* all done */
3766 			spin_lock_bh(&cmd->istate_lock);
3767 			cmd->i_state = ISTATE_SENT_STATUS;
3768 			spin_unlock_bh(&cmd->istate_lock);
3769 
3770 			if (atomic_read(&conn->check_immediate_queue))
3771 				return 1;
3772 
3773 			return 0;
3774 		} else if (ret == 2) {
3775 			/* Still must send status,
3776 			   SCF_TRANSPORT_TASK_SENSE was set */
3777 			spin_lock_bh(&cmd->istate_lock);
3778 			cmd->i_state = ISTATE_SEND_STATUS;
3779 			spin_unlock_bh(&cmd->istate_lock);
3780 			state = ISTATE_SEND_STATUS;
3781 			goto check_rsp_state;
3782 		}
3783 
3784 		break;
3785 	case ISTATE_SEND_STATUS:
3786 	case ISTATE_SEND_STATUS_RECOVERY:
3787 		ret = iscsit_send_response(cmd, conn);
3788 		break;
3789 	case ISTATE_SEND_LOGOUTRSP:
3790 		ret = iscsit_send_logout(cmd, conn);
3791 		break;
3792 	case ISTATE_SEND_ASYNCMSG:
3793 		ret = iscsit_send_conn_drop_async_message(
3794 			cmd, conn);
3795 		break;
3796 	case ISTATE_SEND_NOPIN:
3797 		ret = iscsit_send_nopin(cmd, conn);
3798 		break;
3799 	case ISTATE_SEND_REJECT:
3800 		ret = iscsit_send_reject(cmd, conn);
3801 		break;
3802 	case ISTATE_SEND_TASKMGTRSP:
3803 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3804 		if (ret != 0)
3805 			break;
3806 		ret = iscsit_tmr_post_handler(cmd, conn);
3807 		if (ret != 0)
3808 			iscsit_fall_back_to_erl0(conn->sess);
3809 		break;
3810 	case ISTATE_SEND_TEXTRSP:
3811 		ret = iscsit_send_text_rsp(cmd, conn);
3812 		break;
3813 	default:
3814 		pr_err("Unknown Opcode: 0x%02x ITT:"
3815 		       " 0x%08x, i_state: %d on CID: %hu\n",
3816 		       cmd->iscsi_opcode, cmd->init_task_tag,
3817 		       state, conn->cid);
3818 		goto err;
3819 	}
3820 	if (ret < 0)
3821 		goto err;
3822 
3823 	switch (state) {
3824 	case ISTATE_SEND_LOGOUTRSP:
3825 		if (!iscsit_logout_post_handler(cmd, conn))
3826 			return -ECONNRESET;
3827 		fallthrough;
3828 	case ISTATE_SEND_STATUS:
3829 	case ISTATE_SEND_ASYNCMSG:
3830 	case ISTATE_SEND_NOPIN:
3831 	case ISTATE_SEND_STATUS_RECOVERY:
3832 	case ISTATE_SEND_TEXTRSP:
3833 	case ISTATE_SEND_TASKMGTRSP:
3834 	case ISTATE_SEND_REJECT:
3835 		spin_lock_bh(&cmd->istate_lock);
3836 		cmd->i_state = ISTATE_SENT_STATUS;
3837 		spin_unlock_bh(&cmd->istate_lock);
3838 		break;
3839 	default:
3840 		pr_err("Unknown Opcode: 0x%02x ITT:"
3841 		       " 0x%08x, i_state: %d on CID: %hu\n",
3842 		       cmd->iscsi_opcode, cmd->init_task_tag,
3843 		       cmd->i_state, conn->cid);
3844 		goto err;
3845 	}
3846 
3847 	if (atomic_read(&conn->check_immediate_queue))
3848 		return 1;
3849 
3850 	return 0;
3851 
3852 err:
3853 	return -1;
3854 }
3855 EXPORT_SYMBOL(iscsit_response_queue);
3856 
3857 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3858 {
3859 	struct iscsit_transport *t = conn->conn_transport;
3860 	struct iscsi_queue_req *qr;
3861 	struct iscsi_cmd *cmd;
3862 	u8 state;
3863 	int ret;
3864 
3865 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3866 		cmd = qr->cmd;
3867 		state = qr->state;
3868 		kmem_cache_free(lio_qr_cache, qr);
3869 
3870 		ret = t->iscsit_response_queue(conn, cmd, state);
3871 		if (ret == 1 || ret < 0)
3872 			return ret;
3873 	}
3874 
3875 	return 0;
3876 }
3877 
3878 int iscsi_target_tx_thread(void *arg)
3879 {
3880 	int ret = 0;
3881 	struct iscsi_conn *conn = arg;
3882 	bool conn_freed = false;
3883 
3884 	/*
3885 	 * Allow ourselves to be interrupted by SIGINT so that a
3886 	 * connection recovery / failure event can be triggered externally.
3887 	 */
3888 	allow_signal(SIGINT);
3889 
3890 	while (!kthread_should_stop()) {
3891 		/*
3892 		 * Ensure that both TX and RX per connection kthreads
3893 		 * are scheduled to run on the same CPU.
3894 		 */
3895 		iscsit_thread_check_cpumask(conn, current, 1);
3896 
3897 		wait_event_interruptible(conn->queues_wq,
3898 					 !iscsit_conn_all_queues_empty(conn));
3899 
3900 		if (signal_pending(current))
3901 			goto transport_err;
3902 
3903 get_immediate:
3904 		ret = iscsit_handle_immediate_queue(conn);
3905 		if (ret < 0)
3906 			goto transport_err;
3907 
3908 		ret = iscsit_handle_response_queue(conn);
3909 		if (ret == 1) {
3910 			goto get_immediate;
3911 		} else if (ret == -ECONNRESET) {
3912 			conn_freed = true;
3913 			goto out;
3914 		} else if (ret < 0) {
3915 			goto transport_err;
3916 		}
3917 	}
3918 
3919 transport_err:
3920 	/*
3921 	 * Avoid the normal connection failure code-path if this connection
3922 	 * is still within LOGIN mode, and iscsi_np process context is
3923 	 * responsible for cleaning up the early connection failure.
3924 	 */
3925 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3926 		iscsit_take_action_for_connection_exit(conn, &conn_freed);
3927 out:
3928 	if (!conn_freed) {
3929 		while (!kthread_should_stop()) {
3930 			msleep(100);
3931 		}
3932 	}
3933 	return 0;
3934 }
3935 
3936 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3937 {
3938 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3939 	struct iscsi_cmd *cmd;
3940 	int ret = 0;
3941 
3942 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3943 	case ISCSI_OP_SCSI_CMD:
3944 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3945 		if (!cmd)
3946 			goto reject;
3947 
3948 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3949 		break;
3950 	case ISCSI_OP_SCSI_DATA_OUT:
3951 		ret = iscsit_handle_data_out(conn, buf);
3952 		break;
3953 	case ISCSI_OP_NOOP_OUT:
3954 		cmd = NULL;
3955 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3956 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3957 			if (!cmd)
3958 				goto reject;
3959 		}
3960 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3961 		break;
3962 	case ISCSI_OP_SCSI_TMFUNC:
3963 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3964 		if (!cmd)
3965 			goto reject;
3966 
3967 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3968 		break;
3969 	case ISCSI_OP_TEXT:
3970 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3971 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3972 			if (!cmd)
3973 				goto reject;
3974 		} else {
3975 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3976 			if (!cmd)
3977 				goto reject;
3978 		}
3979 
3980 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3981 		break;
3982 	case ISCSI_OP_LOGOUT:
3983 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3984 		if (!cmd)
3985 			goto reject;
3986 
3987 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3988 		if (ret > 0)
3989 			wait_for_completion_timeout(&conn->conn_logout_comp,
3990 					SECONDS_FOR_LOGOUT_COMP * HZ);
3991 		break;
3992 	case ISCSI_OP_SNACK:
3993 		ret = iscsit_handle_snack(conn, buf);
3994 		break;
3995 	default:
3996 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3997 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3998 			pr_err("Cannot recover from unknown"
3999 			" opcode while ERL=0, closing iSCSI connection.\n");
4000 			return -1;
4001 		}
4002 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
4003 		       " closing iSCSI connection.\n");
4004 		ret = -1;
4005 		break;
4006 	}
4007 
4008 	return ret;
4009 reject:
4010 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4011 }
4012 
4013 static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
4014 {
4015 	bool ret;
4016 
4017 	spin_lock_bh(&conn->state_lock);
4018 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
4019 	spin_unlock_bh(&conn->state_lock);
4020 
4021 	return ret;
4022 }
4023 
4024 static void iscsit_get_rx_pdu(struct iscsi_conn *conn)
4025 {
4026 	int ret;
4027 	u8 *buffer, opcode;
4028 	u32 checksum = 0, digest = 0;
4029 	struct kvec iov;
4030 
4031 	buffer = kcalloc(ISCSI_HDR_LEN, sizeof(*buffer), GFP_KERNEL);
4032 	if (!buffer)
4033 		return;
4034 
4035 	while (!kthread_should_stop()) {
4036 		/*
4037 		 * Ensure that both TX and RX per connection kthreads
4038 		 * are scheduled to run on the same CPU.
4039 		 */
4040 		iscsit_thread_check_cpumask(conn, current, 0);
4041 
4042 		memset(&iov, 0, sizeof(struct kvec));
4043 
4044 		iov.iov_base	= buffer;
4045 		iov.iov_len	= ISCSI_HDR_LEN;
4046 
4047 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4048 		if (ret != ISCSI_HDR_LEN) {
4049 			iscsit_rx_thread_wait_for_tcp(conn);
4050 			break;
4051 		}
4052 
4053 		if (conn->conn_ops->HeaderDigest) {
4054 			iov.iov_base	= &digest;
4055 			iov.iov_len	= ISCSI_CRC_LEN;
4056 
4057 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4058 			if (ret != ISCSI_CRC_LEN) {
4059 				iscsit_rx_thread_wait_for_tcp(conn);
4060 				break;
4061 			}
4062 
4063 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, buffer,
4064 						  ISCSI_HDR_LEN, 0, NULL,
4065 						  &checksum);
4066 
4067 			if (digest != checksum) {
4068 				pr_err("HeaderDigest CRC32C failed,"
4069 					" received 0x%08x, computed 0x%08x\n",
4070 					digest, checksum);
4071 				/*
4072 				 * Set the PDU to 0xff so it will intentionally
4073 				 * hit default in the switch below.
4074 				 */
4075 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4076 				atomic_long_inc(&conn->sess->conn_digest_errors);
4077 			} else {
4078 				pr_debug("Got HeaderDigest CRC32C"
4079 						" 0x%08x\n", checksum);
4080 			}
4081 		}
4082 
4083 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4084 			break;
4085 
4086 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4087 
4088 		if (conn->sess->sess_ops->SessionType &&
4089 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4090 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4091 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4092 			" while in Discovery Session, rejecting.\n", opcode);
4093 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4094 					  buffer);
4095 			break;
4096 		}
4097 
4098 		ret = iscsi_target_rx_opcode(conn, buffer);
4099 		if (ret < 0)
4100 			break;
4101 	}
4102 
4103 	kfree(buffer);
4104 }
4105 
4106 int iscsi_target_rx_thread(void *arg)
4107 {
4108 	int rc;
4109 	struct iscsi_conn *conn = arg;
4110 	bool conn_freed = false;
4111 
4112 	/*
4113 	 * Allow ourselves to be interrupted by SIGINT so that a
4114 	 * connection recovery / failure event can be triggered externally.
4115 	 */
4116 	allow_signal(SIGINT);
4117 	/*
4118 	 * Wait for iscsi_post_login_handler() to complete before allowing
4119 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4120 	 */
4121 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4122 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4123 		goto out;
4124 
4125 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4126 		return 0;
4127 
4128 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4129 
4130 	if (!signal_pending(current))
4131 		atomic_set(&conn->transport_failed, 1);
4132 	iscsit_take_action_for_connection_exit(conn, &conn_freed);
4133 
4134 out:
4135 	if (!conn_freed) {
4136 		while (!kthread_should_stop()) {
4137 			msleep(100);
4138 		}
4139 	}
4140 
4141 	return 0;
4142 }
4143 
4144 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4145 {
4146 	LIST_HEAD(tmp_list);
4147 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4148 	struct iscsi_session *sess = conn->sess;
4149 	/*
4150 	 * We expect this function to only ever be called from either RX or TX
4151 	 * thread context via iscsit_close_connection() once the other context
4152 	 * has been reset -> returned sleeping pre-handler state.
4153 	 */
4154 	spin_lock_bh(&conn->cmd_lock);
4155 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4156 
4157 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4158 		struct se_cmd *se_cmd = &cmd->se_cmd;
4159 
4160 		if (se_cmd->se_tfo != NULL) {
4161 			spin_lock_irq(&se_cmd->t_state_lock);
4162 			if (se_cmd->transport_state & CMD_T_ABORTED) {
4163 				/*
4164 				 * LIO's abort path owns the cleanup for this,
4165 				 * so put it back on the list and let
4166 				 * aborted_task handle it.
4167 				 */
4168 				list_move_tail(&cmd->i_conn_node,
4169 					       &conn->conn_cmd_list);
4170 			} else {
4171 				se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4172 			}
4173 			spin_unlock_irq(&se_cmd->t_state_lock);
4174 		}
4175 	}
4176 	spin_unlock_bh(&conn->cmd_lock);
4177 
4178 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4179 		list_del_init(&cmd->i_conn_node);
4180 
4181 		iscsit_increment_maxcmdsn(cmd, sess);
4182 		iscsit_free_cmd(cmd, true);
4183 
4184 	}
4185 }
4186 
4187 static void iscsit_stop_timers_for_cmds(
4188 	struct iscsi_conn *conn)
4189 {
4190 	struct iscsi_cmd *cmd;
4191 
4192 	spin_lock_bh(&conn->cmd_lock);
4193 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4194 		if (cmd->data_direction == DMA_TO_DEVICE)
4195 			iscsit_stop_dataout_timer(cmd);
4196 	}
4197 	spin_unlock_bh(&conn->cmd_lock);
4198 }
4199 
4200 int iscsit_close_connection(
4201 	struct iscsi_conn *conn)
4202 {
4203 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4204 	struct iscsi_session	*sess = conn->sess;
4205 
4206 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4207 		" %u\n", conn->cid, sess->sid);
4208 	/*
4209 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4210 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4211 	 * sleeping and the logout response never got sent because the
4212 	 * connection failed.
4213 	 *
4214 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4215 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4216 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4217 	 * and to avoid iscsi_conn pointer dereference in iser-target code.
4218 	 */
4219 	if (!conn->conn_transport->rdma_shutdown)
4220 		complete(&conn->conn_logout_comp);
4221 
4222 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4223 		if (conn->tx_thread &&
4224 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4225 			send_sig(SIGINT, conn->tx_thread, 1);
4226 			kthread_stop(conn->tx_thread);
4227 		}
4228 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4229 		if (conn->rx_thread &&
4230 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4231 			send_sig(SIGINT, conn->rx_thread, 1);
4232 			kthread_stop(conn->rx_thread);
4233 		}
4234 	}
4235 
4236 	spin_lock(&iscsit_global->ts_bitmap_lock);
4237 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4238 			      get_order(1));
4239 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4240 
4241 	iscsit_stop_timers_for_cmds(conn);
4242 	iscsit_stop_nopin_response_timer(conn);
4243 	iscsit_stop_nopin_timer(conn);
4244 
4245 	if (conn->conn_transport->iscsit_wait_conn)
4246 		conn->conn_transport->iscsit_wait_conn(conn);
4247 
4248 	/*
4249 	 * During Connection recovery drop unacknowledged out of order
4250 	 * commands for this connection, and prepare the other commands
4251 	 * for reallegiance.
4252 	 *
4253 	 * During normal operation clear the out of order commands (but
4254 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4255 	 * struct iscsi_cmds.
4256 	 */
4257 	if (atomic_read(&conn->connection_recovery)) {
4258 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4259 		iscsit_prepare_cmds_for_reallegiance(conn);
4260 	} else {
4261 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4262 		iscsit_release_commands_from_conn(conn);
4263 	}
4264 	iscsit_free_queue_reqs_for_conn(conn);
4265 
4266 	/*
4267 	 * Handle decrementing session or connection usage count if
4268 	 * a logout response was not able to be sent because the
4269 	 * connection failed.  Fall back to Session Recovery here.
4270 	 */
4271 	if (atomic_read(&conn->conn_logout_remove)) {
4272 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4273 			iscsit_dec_conn_usage_count(conn);
4274 			iscsit_dec_session_usage_count(sess);
4275 		}
4276 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4277 			iscsit_dec_conn_usage_count(conn);
4278 
4279 		atomic_set(&conn->conn_logout_remove, 0);
4280 		atomic_set(&sess->session_reinstatement, 0);
4281 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4282 	}
4283 
4284 	spin_lock_bh(&sess->conn_lock);
4285 	list_del(&conn->conn_list);
4286 
4287 	/*
4288 	 * Attempt to let the Initiator know this connection failed by
4289 	 * sending an Connection Dropped Async Message on another
4290 	 * active connection.
4291 	 */
4292 	if (atomic_read(&conn->connection_recovery))
4293 		iscsit_build_conn_drop_async_message(conn);
4294 
4295 	spin_unlock_bh(&sess->conn_lock);
4296 
4297 	/*
4298 	 * If connection reinstatement is being performed on this connection,
4299 	 * up the connection reinstatement semaphore that is being blocked on
4300 	 * in iscsit_cause_connection_reinstatement().
4301 	 */
4302 	spin_lock_bh(&conn->state_lock);
4303 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4304 		spin_unlock_bh(&conn->state_lock);
4305 		complete(&conn->conn_wait_comp);
4306 		wait_for_completion(&conn->conn_post_wait_comp);
4307 		spin_lock_bh(&conn->state_lock);
4308 	}
4309 
4310 	/*
4311 	 * If connection reinstatement is being performed on this connection
4312 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4313 	 * connection wait rcfr semaphore that is being blocked on
4314 	 * an iscsit_connection_reinstatement_rcfr().
4315 	 */
4316 	if (atomic_read(&conn->connection_wait_rcfr)) {
4317 		spin_unlock_bh(&conn->state_lock);
4318 		complete(&conn->conn_wait_rcfr_comp);
4319 		wait_for_completion(&conn->conn_post_wait_comp);
4320 		spin_lock_bh(&conn->state_lock);
4321 	}
4322 	atomic_set(&conn->connection_reinstatement, 1);
4323 	spin_unlock_bh(&conn->state_lock);
4324 
4325 	/*
4326 	 * If any other processes are accessing this connection pointer we
4327 	 * must wait until they have completed.
4328 	 */
4329 	iscsit_check_conn_usage_count(conn);
4330 
4331 	ahash_request_free(conn->conn_tx_hash);
4332 	if (conn->conn_rx_hash) {
4333 		struct crypto_ahash *tfm;
4334 
4335 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4336 		ahash_request_free(conn->conn_rx_hash);
4337 		crypto_free_ahash(tfm);
4338 	}
4339 
4340 	if (conn->sock)
4341 		sock_release(conn->sock);
4342 
4343 	if (conn->conn_transport->iscsit_free_conn)
4344 		conn->conn_transport->iscsit_free_conn(conn);
4345 
4346 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4347 	conn->conn_state = TARG_CONN_STATE_FREE;
4348 	iscsit_free_conn(conn);
4349 
4350 	spin_lock_bh(&sess->conn_lock);
4351 	atomic_dec(&sess->nconn);
4352 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4353 		" %s\n", atomic_read(&sess->nconn),
4354 		sess->sess_ops->InitiatorName);
4355 	/*
4356 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4357 	 * Session that they all fail.
4358 	 */
4359 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4360 	     !atomic_read(&sess->session_logout))
4361 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4362 
4363 	/*
4364 	 * If this was not the last connection in the session, and we are
4365 	 * performing session reinstatement or falling back to ERL=0, call
4366 	 * iscsit_stop_session() without sleeping to shutdown the other
4367 	 * active connections.
4368 	 */
4369 	if (atomic_read(&sess->nconn)) {
4370 		if (!atomic_read(&sess->session_reinstatement) &&
4371 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4372 			spin_unlock_bh(&sess->conn_lock);
4373 			return 0;
4374 		}
4375 		if (!atomic_read(&sess->session_stop_active)) {
4376 			atomic_set(&sess->session_stop_active, 1);
4377 			spin_unlock_bh(&sess->conn_lock);
4378 			iscsit_stop_session(sess, 0, 0);
4379 			return 0;
4380 		}
4381 		spin_unlock_bh(&sess->conn_lock);
4382 		return 0;
4383 	}
4384 
4385 	/*
4386 	 * If this was the last connection in the session and one of the
4387 	 * following is occurring:
4388 	 *
4389 	 * Session Reinstatement is not being performed, and are falling back
4390 	 * to ERL=0 call iscsit_close_session().
4391 	 *
4392 	 * Session Logout was requested.  iscsit_close_session() will be called
4393 	 * elsewhere.
4394 	 *
4395 	 * Session Continuation is not being performed, start the Time2Retain
4396 	 * handler and check if sleep_on_sess_wait_sem is active.
4397 	 */
4398 	if (!atomic_read(&sess->session_reinstatement) &&
4399 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4400 		spin_unlock_bh(&sess->conn_lock);
4401 		complete_all(&sess->session_wait_comp);
4402 		iscsit_close_session(sess, true);
4403 
4404 		return 0;
4405 	} else if (atomic_read(&sess->session_logout)) {
4406 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4407 		sess->session_state = TARG_SESS_STATE_FREE;
4408 
4409 		if (atomic_read(&sess->session_close)) {
4410 			spin_unlock_bh(&sess->conn_lock);
4411 			complete_all(&sess->session_wait_comp);
4412 			iscsit_close_session(sess, true);
4413 		} else {
4414 			spin_unlock_bh(&sess->conn_lock);
4415 		}
4416 
4417 		return 0;
4418 	} else {
4419 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4420 		sess->session_state = TARG_SESS_STATE_FAILED;
4421 
4422 		if (!atomic_read(&sess->session_continuation))
4423 			iscsit_start_time2retain_handler(sess);
4424 
4425 		if (atomic_read(&sess->session_close)) {
4426 			spin_unlock_bh(&sess->conn_lock);
4427 			complete_all(&sess->session_wait_comp);
4428 			iscsit_close_session(sess, true);
4429 		} else {
4430 			spin_unlock_bh(&sess->conn_lock);
4431 		}
4432 
4433 		return 0;
4434 	}
4435 }
4436 
4437 /*
4438  * If the iSCSI Session for the iSCSI Initiator Node exists,
4439  * forcefully shutdown the iSCSI NEXUS.
4440  */
4441 int iscsit_close_session(struct iscsi_session *sess, bool can_sleep)
4442 {
4443 	struct iscsi_portal_group *tpg = sess->tpg;
4444 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4445 
4446 	if (atomic_read(&sess->nconn)) {
4447 		pr_err("%d connection(s) still exist for iSCSI session"
4448 			" to %s\n", atomic_read(&sess->nconn),
4449 			sess->sess_ops->InitiatorName);
4450 		BUG();
4451 	}
4452 
4453 	spin_lock_bh(&se_tpg->session_lock);
4454 	atomic_set(&sess->session_logout, 1);
4455 	atomic_set(&sess->session_reinstatement, 1);
4456 	iscsit_stop_time2retain_timer(sess);
4457 	spin_unlock_bh(&se_tpg->session_lock);
4458 
4459 	/*
4460 	 * transport_deregister_session_configfs() will clear the
4461 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4462 	 * can be setting it again with __transport_register_session() in
4463 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4464 	 * completes in iscsi_np context.
4465 	 */
4466 	transport_deregister_session_configfs(sess->se_sess);
4467 
4468 	/*
4469 	 * If any other processes are accessing this session pointer we must
4470 	 * wait until they have completed.  If we are in an interrupt (the
4471 	 * time2retain handler) and contain and active session usage count we
4472 	 * restart the timer and exit.
4473 	 */
4474 	if (iscsit_check_session_usage_count(sess, can_sleep)) {
4475 		atomic_set(&sess->session_logout, 0);
4476 		iscsit_start_time2retain_handler(sess);
4477 		return 0;
4478 	}
4479 
4480 	transport_deregister_session(sess->se_sess);
4481 
4482 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4483 		iscsit_free_connection_recovery_entries(sess);
4484 
4485 	iscsit_free_all_ooo_cmdsns(sess);
4486 
4487 	spin_lock_bh(&se_tpg->session_lock);
4488 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4489 	sess->session_state = TARG_SESS_STATE_FREE;
4490 	pr_debug("Released iSCSI session from node: %s\n",
4491 			sess->sess_ops->InitiatorName);
4492 	tpg->nsessions--;
4493 	if (tpg->tpg_tiqn)
4494 		tpg->tpg_tiqn->tiqn_nsessions--;
4495 
4496 	pr_debug("Decremented number of active iSCSI Sessions on"
4497 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4498 
4499 	ida_free(&sess_ida, sess->session_index);
4500 	kfree(sess->sess_ops);
4501 	sess->sess_ops = NULL;
4502 	spin_unlock_bh(&se_tpg->session_lock);
4503 
4504 	kfree(sess);
4505 	return 0;
4506 }
4507 
4508 static void iscsit_logout_post_handler_closesession(
4509 	struct iscsi_conn *conn)
4510 {
4511 	struct iscsi_session *sess = conn->sess;
4512 	int sleep = 1;
4513 	/*
4514 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4515 	 * context during session logout, so clear tx_thread_active and
4516 	 * sleep if iscsit_close_connection() has not already occured.
4517 	 *
4518 	 * Since iser-target invokes this logic from it's own workqueue,
4519 	 * always sleep waiting for RX/TX thread shutdown to complete
4520 	 * within iscsit_close_connection().
4521 	 */
4522 	if (!conn->conn_transport->rdma_shutdown) {
4523 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4524 		if (!sleep)
4525 			return;
4526 	}
4527 
4528 	atomic_set(&conn->conn_logout_remove, 0);
4529 	complete(&conn->conn_logout_comp);
4530 
4531 	iscsit_dec_conn_usage_count(conn);
4532 	atomic_set(&sess->session_close, 1);
4533 	iscsit_stop_session(sess, sleep, sleep);
4534 	iscsit_dec_session_usage_count(sess);
4535 }
4536 
4537 static void iscsit_logout_post_handler_samecid(
4538 	struct iscsi_conn *conn)
4539 {
4540 	int sleep = 1;
4541 
4542 	if (!conn->conn_transport->rdma_shutdown) {
4543 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4544 		if (!sleep)
4545 			return;
4546 	}
4547 
4548 	atomic_set(&conn->conn_logout_remove, 0);
4549 	complete(&conn->conn_logout_comp);
4550 
4551 	iscsit_cause_connection_reinstatement(conn, sleep);
4552 	iscsit_dec_conn_usage_count(conn);
4553 }
4554 
4555 static void iscsit_logout_post_handler_diffcid(
4556 	struct iscsi_conn *conn,
4557 	u16 cid)
4558 {
4559 	struct iscsi_conn *l_conn;
4560 	struct iscsi_session *sess = conn->sess;
4561 	bool conn_found = false;
4562 
4563 	if (!sess)
4564 		return;
4565 
4566 	spin_lock_bh(&sess->conn_lock);
4567 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4568 		if (l_conn->cid == cid) {
4569 			iscsit_inc_conn_usage_count(l_conn);
4570 			conn_found = true;
4571 			break;
4572 		}
4573 	}
4574 	spin_unlock_bh(&sess->conn_lock);
4575 
4576 	if (!conn_found)
4577 		return;
4578 
4579 	if (l_conn->sock)
4580 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4581 
4582 	spin_lock_bh(&l_conn->state_lock);
4583 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4584 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4585 	spin_unlock_bh(&l_conn->state_lock);
4586 
4587 	iscsit_cause_connection_reinstatement(l_conn, 1);
4588 	iscsit_dec_conn_usage_count(l_conn);
4589 }
4590 
4591 /*
4592  *	Return of 0 causes the TX thread to restart.
4593  */
4594 int iscsit_logout_post_handler(
4595 	struct iscsi_cmd *cmd,
4596 	struct iscsi_conn *conn)
4597 {
4598 	int ret = 0;
4599 
4600 	switch (cmd->logout_reason) {
4601 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4602 		switch (cmd->logout_response) {
4603 		case ISCSI_LOGOUT_SUCCESS:
4604 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4605 		default:
4606 			iscsit_logout_post_handler_closesession(conn);
4607 			break;
4608 		}
4609 		break;
4610 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4611 		if (conn->cid == cmd->logout_cid) {
4612 			switch (cmd->logout_response) {
4613 			case ISCSI_LOGOUT_SUCCESS:
4614 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4615 			default:
4616 				iscsit_logout_post_handler_samecid(conn);
4617 				break;
4618 			}
4619 		} else {
4620 			switch (cmd->logout_response) {
4621 			case ISCSI_LOGOUT_SUCCESS:
4622 				iscsit_logout_post_handler_diffcid(conn,
4623 					cmd->logout_cid);
4624 				break;
4625 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4626 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4627 			default:
4628 				break;
4629 			}
4630 			ret = 1;
4631 		}
4632 		break;
4633 	case ISCSI_LOGOUT_REASON_RECOVERY:
4634 		switch (cmd->logout_response) {
4635 		case ISCSI_LOGOUT_SUCCESS:
4636 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4637 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4638 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4639 		default:
4640 			break;
4641 		}
4642 		ret = 1;
4643 		break;
4644 	default:
4645 		break;
4646 
4647 	}
4648 	return ret;
4649 }
4650 EXPORT_SYMBOL(iscsit_logout_post_handler);
4651 
4652 void iscsit_fail_session(struct iscsi_session *sess)
4653 {
4654 	struct iscsi_conn *conn;
4655 
4656 	spin_lock_bh(&sess->conn_lock);
4657 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4658 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4659 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4660 	}
4661 	spin_unlock_bh(&sess->conn_lock);
4662 
4663 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4664 	sess->session_state = TARG_SESS_STATE_FAILED;
4665 }
4666 
4667 void iscsit_stop_session(
4668 	struct iscsi_session *sess,
4669 	int session_sleep,
4670 	int connection_sleep)
4671 {
4672 	u16 conn_count = atomic_read(&sess->nconn);
4673 	struct iscsi_conn *conn, *conn_tmp = NULL;
4674 	int is_last;
4675 
4676 	spin_lock_bh(&sess->conn_lock);
4677 
4678 	if (connection_sleep) {
4679 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4680 				conn_list) {
4681 			if (conn_count == 0)
4682 				break;
4683 
4684 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4685 				is_last = 1;
4686 			} else {
4687 				iscsit_inc_conn_usage_count(conn_tmp);
4688 				is_last = 0;
4689 			}
4690 			iscsit_inc_conn_usage_count(conn);
4691 
4692 			spin_unlock_bh(&sess->conn_lock);
4693 			iscsit_cause_connection_reinstatement(conn, 1);
4694 			spin_lock_bh(&sess->conn_lock);
4695 
4696 			iscsit_dec_conn_usage_count(conn);
4697 			if (is_last == 0)
4698 				iscsit_dec_conn_usage_count(conn_tmp);
4699 			conn_count--;
4700 		}
4701 	} else {
4702 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4703 			iscsit_cause_connection_reinstatement(conn, 0);
4704 	}
4705 
4706 	if (session_sleep && atomic_read(&sess->nconn)) {
4707 		spin_unlock_bh(&sess->conn_lock);
4708 		wait_for_completion(&sess->session_wait_comp);
4709 	} else
4710 		spin_unlock_bh(&sess->conn_lock);
4711 }
4712 
4713 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4714 {
4715 	struct iscsi_session *sess;
4716 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4717 	struct se_session *se_sess, *se_sess_tmp;
4718 	LIST_HEAD(free_list);
4719 	int session_count = 0;
4720 
4721 	spin_lock_bh(&se_tpg->session_lock);
4722 	if (tpg->nsessions && !force) {
4723 		spin_unlock_bh(&se_tpg->session_lock);
4724 		return -1;
4725 	}
4726 
4727 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4728 			sess_list) {
4729 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4730 
4731 		spin_lock(&sess->conn_lock);
4732 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4733 		    atomic_read(&sess->session_logout) ||
4734 		    atomic_read(&sess->session_close) ||
4735 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4736 			spin_unlock(&sess->conn_lock);
4737 			continue;
4738 		}
4739 		iscsit_inc_session_usage_count(sess);
4740 		atomic_set(&sess->session_reinstatement, 1);
4741 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4742 		atomic_set(&sess->session_close, 1);
4743 		spin_unlock(&sess->conn_lock);
4744 
4745 		list_move_tail(&se_sess->sess_list, &free_list);
4746 	}
4747 	spin_unlock_bh(&se_tpg->session_lock);
4748 
4749 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4750 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4751 
4752 		list_del_init(&se_sess->sess_list);
4753 		iscsit_stop_session(sess, 1, 1);
4754 		iscsit_dec_session_usage_count(sess);
4755 		session_count++;
4756 	}
4757 
4758 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4759 			" Group: %hu\n", session_count, tpg->tpgt);
4760 	return 0;
4761 }
4762 
4763 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4764 MODULE_VERSION("4.1.x");
4765 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4766 MODULE_LICENSE("GPL");
4767 
4768 module_init(iscsi_target_init_module);
4769 module_exit(iscsi_target_cleanup_module);
4770