1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18 
19 #include <crypto/hash.h>
20 #include <linux/string.h>
21 #include <linux/kthread.h>
22 #include <linux/completion.h>
23 #include <linux/module.h>
24 #include <linux/vmalloc.h>
25 #include <linux/idr.h>
26 #include <linux/delay.h>
27 #include <linux/sched/signal.h>
28 #include <asm/unaligned.h>
29 #include <net/ipv6.h>
30 #include <scsi/scsi_proto.h>
31 #include <scsi/iscsi_proto.h>
32 #include <scsi/scsi_tcq.h>
33 #include <target/target_core_base.h>
34 #include <target/target_core_fabric.h>
35 
36 #include <target/iscsi/iscsi_target_core.h>
37 #include "iscsi_target_parameters.h"
38 #include "iscsi_target_seq_pdu_list.h"
39 #include "iscsi_target_datain_values.h"
40 #include "iscsi_target_erl0.h"
41 #include "iscsi_target_erl1.h"
42 #include "iscsi_target_erl2.h"
43 #include "iscsi_target_login.h"
44 #include "iscsi_target_tmr.h"
45 #include "iscsi_target_tpg.h"
46 #include "iscsi_target_util.h"
47 #include "iscsi_target.h"
48 #include "iscsi_target_device.h"
49 #include <target/iscsi/iscsi_target_stat.h>
50 
51 #include <target/iscsi/iscsi_transport.h>
52 
53 static LIST_HEAD(g_tiqn_list);
54 static LIST_HEAD(g_np_list);
55 static DEFINE_SPINLOCK(tiqn_lock);
56 static DEFINE_MUTEX(np_lock);
57 
58 static struct idr tiqn_idr;
59 struct idr sess_idr;
60 struct mutex auth_id_lock;
61 spinlock_t sess_idr_lock;
62 
63 struct iscsit_global *iscsit_global;
64 
65 struct kmem_cache *lio_qr_cache;
66 struct kmem_cache *lio_dr_cache;
67 struct kmem_cache *lio_ooo_cache;
68 struct kmem_cache *lio_r2t_cache;
69 
70 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
71 			struct iscsi_scsi_req *, u32);
72 
73 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
74 {
75 	struct iscsi_tiqn *tiqn = NULL;
76 
77 	spin_lock(&tiqn_lock);
78 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
79 		if (!strcmp(tiqn->tiqn, buf)) {
80 
81 			spin_lock(&tiqn->tiqn_state_lock);
82 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
83 				tiqn->tiqn_access_count++;
84 				spin_unlock(&tiqn->tiqn_state_lock);
85 				spin_unlock(&tiqn_lock);
86 				return tiqn;
87 			}
88 			spin_unlock(&tiqn->tiqn_state_lock);
89 		}
90 	}
91 	spin_unlock(&tiqn_lock);
92 
93 	return NULL;
94 }
95 
96 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
97 {
98 	spin_lock(&tiqn->tiqn_state_lock);
99 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
100 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
101 		spin_unlock(&tiqn->tiqn_state_lock);
102 		return 0;
103 	}
104 	spin_unlock(&tiqn->tiqn_state_lock);
105 
106 	return -1;
107 }
108 
109 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
110 {
111 	spin_lock(&tiqn->tiqn_state_lock);
112 	tiqn->tiqn_access_count--;
113 	spin_unlock(&tiqn->tiqn_state_lock);
114 }
115 
116 /*
117  * Note that IQN formatting is expected to be done in userspace, and
118  * no explict IQN format checks are done here.
119  */
120 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
121 {
122 	struct iscsi_tiqn *tiqn = NULL;
123 	int ret;
124 
125 	if (strlen(buf) >= ISCSI_IQN_LEN) {
126 		pr_err("Target IQN exceeds %d bytes\n",
127 				ISCSI_IQN_LEN);
128 		return ERR_PTR(-EINVAL);
129 	}
130 
131 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
132 	if (!tiqn) {
133 		pr_err("Unable to allocate struct iscsi_tiqn\n");
134 		return ERR_PTR(-ENOMEM);
135 	}
136 
137 	sprintf(tiqn->tiqn, "%s", buf);
138 	INIT_LIST_HEAD(&tiqn->tiqn_list);
139 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
140 	spin_lock_init(&tiqn->tiqn_state_lock);
141 	spin_lock_init(&tiqn->tiqn_tpg_lock);
142 	spin_lock_init(&tiqn->sess_err_stats.lock);
143 	spin_lock_init(&tiqn->login_stats.lock);
144 	spin_lock_init(&tiqn->logout_stats.lock);
145 
146 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
147 
148 	idr_preload(GFP_KERNEL);
149 	spin_lock(&tiqn_lock);
150 
151 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
152 	if (ret < 0) {
153 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
154 		spin_unlock(&tiqn_lock);
155 		idr_preload_end();
156 		kfree(tiqn);
157 		return ERR_PTR(ret);
158 	}
159 	tiqn->tiqn_index = ret;
160 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
161 
162 	spin_unlock(&tiqn_lock);
163 	idr_preload_end();
164 
165 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
166 
167 	return tiqn;
168 
169 }
170 
171 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
172 {
173 	/*
174 	 * Wait for accesses to said struct iscsi_tiqn to end.
175 	 */
176 	spin_lock(&tiqn->tiqn_state_lock);
177 	while (tiqn->tiqn_access_count != 0) {
178 		spin_unlock(&tiqn->tiqn_state_lock);
179 		msleep(10);
180 		spin_lock(&tiqn->tiqn_state_lock);
181 	}
182 	spin_unlock(&tiqn->tiqn_state_lock);
183 }
184 
185 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
186 {
187 	/*
188 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
189 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
190 	 * attempts to access this struct iscsi_tiqn will fail from both transport
191 	 * fabric and control code paths.
192 	 */
193 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
194 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
195 		return;
196 	}
197 
198 	iscsit_wait_for_tiqn(tiqn);
199 
200 	spin_lock(&tiqn_lock);
201 	list_del(&tiqn->tiqn_list);
202 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
203 	spin_unlock(&tiqn_lock);
204 
205 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
206 			tiqn->tiqn);
207 	kfree(tiqn);
208 }
209 
210 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
211 {
212 	int ret;
213 	/*
214 	 * Determine if the network portal is accepting storage traffic.
215 	 */
216 	spin_lock_bh(&np->np_thread_lock);
217 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
218 		spin_unlock_bh(&np->np_thread_lock);
219 		return -1;
220 	}
221 	spin_unlock_bh(&np->np_thread_lock);
222 	/*
223 	 * Determine if the portal group is accepting storage traffic.
224 	 */
225 	spin_lock_bh(&tpg->tpg_state_lock);
226 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
227 		spin_unlock_bh(&tpg->tpg_state_lock);
228 		return -1;
229 	}
230 	spin_unlock_bh(&tpg->tpg_state_lock);
231 
232 	/*
233 	 * Here we serialize access across the TIQN+TPG Tuple.
234 	 */
235 	ret = down_interruptible(&tpg->np_login_sem);
236 	if (ret != 0)
237 		return -1;
238 
239 	spin_lock_bh(&tpg->tpg_state_lock);
240 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
241 		spin_unlock_bh(&tpg->tpg_state_lock);
242 		up(&tpg->np_login_sem);
243 		return -1;
244 	}
245 	spin_unlock_bh(&tpg->tpg_state_lock);
246 
247 	return 0;
248 }
249 
250 void iscsit_login_kref_put(struct kref *kref)
251 {
252 	struct iscsi_tpg_np *tpg_np = container_of(kref,
253 				struct iscsi_tpg_np, tpg_np_kref);
254 
255 	complete(&tpg_np->tpg_np_comp);
256 }
257 
258 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
259 		       struct iscsi_tpg_np *tpg_np)
260 {
261 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
262 
263 	up(&tpg->np_login_sem);
264 
265 	if (tpg_np)
266 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
267 
268 	if (tiqn)
269 		iscsit_put_tiqn_for_login(tiqn);
270 
271 	return 0;
272 }
273 
274 bool iscsit_check_np_match(
275 	struct sockaddr_storage *sockaddr,
276 	struct iscsi_np *np,
277 	int network_transport)
278 {
279 	struct sockaddr_in *sock_in, *sock_in_e;
280 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
281 	bool ip_match = false;
282 	u16 port, port_e;
283 
284 	if (sockaddr->ss_family == AF_INET6) {
285 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
286 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
287 
288 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
289 			    &sock_in6_e->sin6_addr.in6_u,
290 			    sizeof(struct in6_addr)))
291 			ip_match = true;
292 
293 		port = ntohs(sock_in6->sin6_port);
294 		port_e = ntohs(sock_in6_e->sin6_port);
295 	} else {
296 		sock_in = (struct sockaddr_in *)sockaddr;
297 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
298 
299 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
300 			ip_match = true;
301 
302 		port = ntohs(sock_in->sin_port);
303 		port_e = ntohs(sock_in_e->sin_port);
304 	}
305 
306 	if (ip_match && (port_e == port) &&
307 	    (np->np_network_transport == network_transport))
308 		return true;
309 
310 	return false;
311 }
312 
313 /*
314  * Called with mutex np_lock held
315  */
316 static struct iscsi_np *iscsit_get_np(
317 	struct sockaddr_storage *sockaddr,
318 	int network_transport)
319 {
320 	struct iscsi_np *np;
321 	bool match;
322 
323 	list_for_each_entry(np, &g_np_list, np_list) {
324 		spin_lock_bh(&np->np_thread_lock);
325 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
326 			spin_unlock_bh(&np->np_thread_lock);
327 			continue;
328 		}
329 
330 		match = iscsit_check_np_match(sockaddr, np, network_transport);
331 		if (match) {
332 			/*
333 			 * Increment the np_exports reference count now to
334 			 * prevent iscsit_del_np() below from being called
335 			 * while iscsi_tpg_add_network_portal() is called.
336 			 */
337 			np->np_exports++;
338 			spin_unlock_bh(&np->np_thread_lock);
339 			return np;
340 		}
341 		spin_unlock_bh(&np->np_thread_lock);
342 	}
343 
344 	return NULL;
345 }
346 
347 struct iscsi_np *iscsit_add_np(
348 	struct sockaddr_storage *sockaddr,
349 	int network_transport)
350 {
351 	struct iscsi_np *np;
352 	int ret;
353 
354 	mutex_lock(&np_lock);
355 
356 	/*
357 	 * Locate the existing struct iscsi_np if already active..
358 	 */
359 	np = iscsit_get_np(sockaddr, network_transport);
360 	if (np) {
361 		mutex_unlock(&np_lock);
362 		return np;
363 	}
364 
365 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
366 	if (!np) {
367 		pr_err("Unable to allocate memory for struct iscsi_np\n");
368 		mutex_unlock(&np_lock);
369 		return ERR_PTR(-ENOMEM);
370 	}
371 
372 	np->np_flags |= NPF_IP_NETWORK;
373 	np->np_network_transport = network_transport;
374 	spin_lock_init(&np->np_thread_lock);
375 	init_completion(&np->np_restart_comp);
376 	INIT_LIST_HEAD(&np->np_list);
377 
378 	ret = iscsi_target_setup_login_socket(np, sockaddr);
379 	if (ret != 0) {
380 		kfree(np);
381 		mutex_unlock(&np_lock);
382 		return ERR_PTR(ret);
383 	}
384 
385 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
386 	if (IS_ERR(np->np_thread)) {
387 		pr_err("Unable to create kthread: iscsi_np\n");
388 		ret = PTR_ERR(np->np_thread);
389 		kfree(np);
390 		mutex_unlock(&np_lock);
391 		return ERR_PTR(ret);
392 	}
393 	/*
394 	 * Increment the np_exports reference count now to prevent
395 	 * iscsit_del_np() below from being run while a new call to
396 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
397 	 * active.  We don't need to hold np->np_thread_lock at this
398 	 * point because iscsi_np has not been added to g_np_list yet.
399 	 */
400 	np->np_exports = 1;
401 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
402 
403 	list_add_tail(&np->np_list, &g_np_list);
404 	mutex_unlock(&np_lock);
405 
406 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
407 		&np->np_sockaddr, np->np_transport->name);
408 
409 	return np;
410 }
411 
412 int iscsit_reset_np_thread(
413 	struct iscsi_np *np,
414 	struct iscsi_tpg_np *tpg_np,
415 	struct iscsi_portal_group *tpg,
416 	bool shutdown)
417 {
418 	spin_lock_bh(&np->np_thread_lock);
419 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
420 		spin_unlock_bh(&np->np_thread_lock);
421 		return 0;
422 	}
423 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
424 
425 	if (np->np_thread) {
426 		spin_unlock_bh(&np->np_thread_lock);
427 		send_sig(SIGINT, np->np_thread, 1);
428 		wait_for_completion(&np->np_restart_comp);
429 		spin_lock_bh(&np->np_thread_lock);
430 	}
431 	spin_unlock_bh(&np->np_thread_lock);
432 
433 	if (tpg_np && shutdown) {
434 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
435 
436 		wait_for_completion(&tpg_np->tpg_np_comp);
437 	}
438 
439 	return 0;
440 }
441 
442 static void iscsit_free_np(struct iscsi_np *np)
443 {
444 	if (np->np_socket)
445 		sock_release(np->np_socket);
446 }
447 
448 int iscsit_del_np(struct iscsi_np *np)
449 {
450 	spin_lock_bh(&np->np_thread_lock);
451 	np->np_exports--;
452 	if (np->np_exports) {
453 		np->enabled = true;
454 		spin_unlock_bh(&np->np_thread_lock);
455 		return 0;
456 	}
457 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
458 	spin_unlock_bh(&np->np_thread_lock);
459 
460 	if (np->np_thread) {
461 		/*
462 		 * We need to send the signal to wakeup Linux/Net
463 		 * which may be sleeping in sock_accept()..
464 		 */
465 		send_sig(SIGINT, np->np_thread, 1);
466 		kthread_stop(np->np_thread);
467 		np->np_thread = NULL;
468 	}
469 
470 	np->np_transport->iscsit_free_np(np);
471 
472 	mutex_lock(&np_lock);
473 	list_del(&np->np_list);
474 	mutex_unlock(&np_lock);
475 
476 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
477 		&np->np_sockaddr, np->np_transport->name);
478 
479 	iscsit_put_transport(np->np_transport);
480 	kfree(np);
481 	return 0;
482 }
483 
484 static void iscsit_get_rx_pdu(struct iscsi_conn *);
485 
486 int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
487 {
488 	iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
489 	return 0;
490 }
491 EXPORT_SYMBOL(iscsit_queue_rsp);
492 
493 void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
494 {
495 	bool scsi_cmd = (cmd->iscsi_opcode == ISCSI_OP_SCSI_CMD);
496 
497 	spin_lock_bh(&conn->cmd_lock);
498 	if (!list_empty(&cmd->i_conn_node) &&
499 	    !(cmd->se_cmd.transport_state & CMD_T_FABRIC_STOP))
500 		list_del_init(&cmd->i_conn_node);
501 	spin_unlock_bh(&conn->cmd_lock);
502 
503 	__iscsit_free_cmd(cmd, scsi_cmd, true);
504 }
505 EXPORT_SYMBOL(iscsit_aborted_task);
506 
507 static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
508 				      u32, u32, u8 *, u8 *);
509 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *);
510 
511 static int
512 iscsit_xmit_nondatain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
513 			  const void *data_buf, u32 data_buf_len)
514 {
515 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
516 	struct kvec *iov;
517 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
518 	int ret;
519 
520 	iov = &cmd->iov_misc[0];
521 	iov[niov].iov_base	= cmd->pdu;
522 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
523 
524 	if (conn->conn_ops->HeaderDigest) {
525 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
526 
527 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
528 					  ISCSI_HDR_LEN, 0, NULL,
529 					  (u8 *)header_digest);
530 
531 		iov[0].iov_len += ISCSI_CRC_LEN;
532 		tx_size += ISCSI_CRC_LEN;
533 		pr_debug("Attaching CRC32C HeaderDigest"
534 			 " to opcode 0x%x 0x%08x\n",
535 			 hdr->opcode, *header_digest);
536 	}
537 
538 	if (data_buf_len) {
539 		u32 padding = ((-data_buf_len) & 3);
540 
541 		iov[niov].iov_base	= (void *)data_buf;
542 		iov[niov++].iov_len	= data_buf_len;
543 		tx_size += data_buf_len;
544 
545 		if (padding != 0) {
546 			iov[niov].iov_base = &cmd->pad_bytes;
547 			iov[niov++].iov_len = padding;
548 			tx_size += padding;
549 			pr_debug("Attaching %u additional"
550 				 " padding bytes.\n", padding);
551 		}
552 
553 		if (conn->conn_ops->DataDigest) {
554 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
555 						  data_buf, data_buf_len,
556 						  padding,
557 						  (u8 *)&cmd->pad_bytes,
558 						  (u8 *)&cmd->data_crc);
559 
560 			iov[niov].iov_base = &cmd->data_crc;
561 			iov[niov++].iov_len = ISCSI_CRC_LEN;
562 			tx_size += ISCSI_CRC_LEN;
563 			pr_debug("Attached DataDigest for %u"
564 				 " bytes opcode 0x%x, CRC 0x%08x\n",
565 				 data_buf_len, hdr->opcode, cmd->data_crc);
566 		}
567 	}
568 
569 	cmd->iov_misc_count = niov;
570 	cmd->tx_size = tx_size;
571 
572 	ret = iscsit_send_tx_data(cmd, conn, 1);
573 	if (ret < 0) {
574 		iscsit_tx_thread_wait_for_tcp(conn);
575 		return ret;
576 	}
577 
578 	return 0;
579 }
580 
581 static int iscsit_map_iovec(struct iscsi_cmd *, struct kvec *, u32, u32);
582 static void iscsit_unmap_iovec(struct iscsi_cmd *);
583 static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsi_cmd *,
584 				    u32, u32, u32, u8 *);
585 static int
586 iscsit_xmit_datain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
587 		       const struct iscsi_datain *datain)
588 {
589 	struct kvec *iov;
590 	u32 iov_count = 0, tx_size = 0;
591 	int ret, iov_ret;
592 
593 	iov = &cmd->iov_data[0];
594 	iov[iov_count].iov_base	= cmd->pdu;
595 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
596 	tx_size += ISCSI_HDR_LEN;
597 
598 	if (conn->conn_ops->HeaderDigest) {
599 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
600 
601 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
602 					  ISCSI_HDR_LEN, 0, NULL,
603 					  (u8 *)header_digest);
604 
605 		iov[0].iov_len += ISCSI_CRC_LEN;
606 		tx_size += ISCSI_CRC_LEN;
607 
608 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
609 			 *header_digest);
610 	}
611 
612 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
613 				   datain->offset, datain->length);
614 	if (iov_ret < 0)
615 		return -1;
616 
617 	iov_count += iov_ret;
618 	tx_size += datain->length;
619 
620 	cmd->padding = ((-datain->length) & 3);
621 	if (cmd->padding) {
622 		iov[iov_count].iov_base		= cmd->pad_bytes;
623 		iov[iov_count++].iov_len	= cmd->padding;
624 		tx_size += cmd->padding;
625 
626 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
627 	}
628 
629 	if (conn->conn_ops->DataDigest) {
630 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
631 							 cmd, datain->offset,
632 							 datain->length,
633 							 cmd->padding,
634 							 cmd->pad_bytes);
635 
636 		iov[iov_count].iov_base	= &cmd->data_crc;
637 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
638 		tx_size += ISCSI_CRC_LEN;
639 
640 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
641 			 datain->length + cmd->padding, cmd->data_crc);
642 	}
643 
644 	cmd->iov_data_count = iov_count;
645 	cmd->tx_size = tx_size;
646 
647 	ret = iscsit_fe_sendpage_sg(cmd, conn);
648 
649 	iscsit_unmap_iovec(cmd);
650 
651 	if (ret < 0) {
652 		iscsit_tx_thread_wait_for_tcp(conn);
653 		return ret;
654 	}
655 
656 	return 0;
657 }
658 
659 static int iscsit_xmit_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
660 			   struct iscsi_datain_req *dr, const void *buf,
661 			   u32 buf_len)
662 {
663 	if (dr)
664 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
665 	else
666 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
667 }
668 
669 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
670 {
671 	return TARGET_PROT_NORMAL;
672 }
673 
674 static struct iscsit_transport iscsi_target_transport = {
675 	.name			= "iSCSI/TCP",
676 	.transport_type		= ISCSI_TCP,
677 	.rdma_shutdown		= false,
678 	.owner			= NULL,
679 	.iscsit_setup_np	= iscsit_setup_np,
680 	.iscsit_accept_np	= iscsit_accept_np,
681 	.iscsit_free_np		= iscsit_free_np,
682 	.iscsit_get_login_rx	= iscsit_get_login_rx,
683 	.iscsit_put_login_tx	= iscsit_put_login_tx,
684 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
685 	.iscsit_immediate_queue	= iscsit_immediate_queue,
686 	.iscsit_response_queue	= iscsit_response_queue,
687 	.iscsit_queue_data_in	= iscsit_queue_rsp,
688 	.iscsit_queue_status	= iscsit_queue_rsp,
689 	.iscsit_aborted_task	= iscsit_aborted_task,
690 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
691 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
692 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
693 };
694 
695 static int __init iscsi_target_init_module(void)
696 {
697 	int ret = 0, size;
698 
699 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
700 
701 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
702 	if (!iscsit_global) {
703 		pr_err("Unable to allocate memory for iscsit_global\n");
704 		return -1;
705 	}
706 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
707 	mutex_init(&auth_id_lock);
708 	spin_lock_init(&sess_idr_lock);
709 	idr_init(&tiqn_idr);
710 	idr_init(&sess_idr);
711 
712 	ret = target_register_template(&iscsi_ops);
713 	if (ret)
714 		goto out;
715 
716 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
717 	iscsit_global->ts_bitmap = vzalloc(size);
718 	if (!iscsit_global->ts_bitmap) {
719 		pr_err("Unable to allocate iscsit_global->ts_bitmap\n");
720 		goto configfs_out;
721 	}
722 
723 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
724 			sizeof(struct iscsi_queue_req),
725 			__alignof__(struct iscsi_queue_req), 0, NULL);
726 	if (!lio_qr_cache) {
727 		pr_err("nable to kmem_cache_create() for"
728 				" lio_qr_cache\n");
729 		goto bitmap_out;
730 	}
731 
732 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
733 			sizeof(struct iscsi_datain_req),
734 			__alignof__(struct iscsi_datain_req), 0, NULL);
735 	if (!lio_dr_cache) {
736 		pr_err("Unable to kmem_cache_create() for"
737 				" lio_dr_cache\n");
738 		goto qr_out;
739 	}
740 
741 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
742 			sizeof(struct iscsi_ooo_cmdsn),
743 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
744 	if (!lio_ooo_cache) {
745 		pr_err("Unable to kmem_cache_create() for"
746 				" lio_ooo_cache\n");
747 		goto dr_out;
748 	}
749 
750 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
751 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
752 			0, NULL);
753 	if (!lio_r2t_cache) {
754 		pr_err("Unable to kmem_cache_create() for"
755 				" lio_r2t_cache\n");
756 		goto ooo_out;
757 	}
758 
759 	iscsit_register_transport(&iscsi_target_transport);
760 
761 	if (iscsit_load_discovery_tpg() < 0)
762 		goto r2t_out;
763 
764 	return ret;
765 r2t_out:
766 	iscsit_unregister_transport(&iscsi_target_transport);
767 	kmem_cache_destroy(lio_r2t_cache);
768 ooo_out:
769 	kmem_cache_destroy(lio_ooo_cache);
770 dr_out:
771 	kmem_cache_destroy(lio_dr_cache);
772 qr_out:
773 	kmem_cache_destroy(lio_qr_cache);
774 bitmap_out:
775 	vfree(iscsit_global->ts_bitmap);
776 configfs_out:
777 	/* XXX: this probably wants it to be it's own unwind step.. */
778 	if (iscsit_global->discovery_tpg)
779 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
780 	target_unregister_template(&iscsi_ops);
781 out:
782 	kfree(iscsit_global);
783 	return -ENOMEM;
784 }
785 
786 static void __exit iscsi_target_cleanup_module(void)
787 {
788 	iscsit_release_discovery_tpg();
789 	iscsit_unregister_transport(&iscsi_target_transport);
790 	kmem_cache_destroy(lio_qr_cache);
791 	kmem_cache_destroy(lio_dr_cache);
792 	kmem_cache_destroy(lio_ooo_cache);
793 	kmem_cache_destroy(lio_r2t_cache);
794 
795 	/*
796 	 * Shutdown discovery sessions and disable discovery TPG
797 	 */
798 	if (iscsit_global->discovery_tpg)
799 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
800 
801 	target_unregister_template(&iscsi_ops);
802 
803 	vfree(iscsit_global->ts_bitmap);
804 	kfree(iscsit_global);
805 }
806 
807 int iscsit_add_reject(
808 	struct iscsi_conn *conn,
809 	u8 reason,
810 	unsigned char *buf)
811 {
812 	struct iscsi_cmd *cmd;
813 
814 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
815 	if (!cmd)
816 		return -1;
817 
818 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
819 	cmd->reject_reason = reason;
820 
821 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
822 	if (!cmd->buf_ptr) {
823 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
824 		iscsit_free_cmd(cmd, false);
825 		return -1;
826 	}
827 
828 	spin_lock_bh(&conn->cmd_lock);
829 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
830 	spin_unlock_bh(&conn->cmd_lock);
831 
832 	cmd->i_state = ISTATE_SEND_REJECT;
833 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
834 
835 	return -1;
836 }
837 EXPORT_SYMBOL(iscsit_add_reject);
838 
839 static int iscsit_add_reject_from_cmd(
840 	struct iscsi_cmd *cmd,
841 	u8 reason,
842 	bool add_to_conn,
843 	unsigned char *buf)
844 {
845 	struct iscsi_conn *conn;
846 
847 	if (!cmd->conn) {
848 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
849 				cmd->init_task_tag);
850 		return -1;
851 	}
852 	conn = cmd->conn;
853 
854 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
855 	cmd->reject_reason = reason;
856 
857 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
858 	if (!cmd->buf_ptr) {
859 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
860 		iscsit_free_cmd(cmd, false);
861 		return -1;
862 	}
863 
864 	if (add_to_conn) {
865 		spin_lock_bh(&conn->cmd_lock);
866 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
867 		spin_unlock_bh(&conn->cmd_lock);
868 	}
869 
870 	cmd->i_state = ISTATE_SEND_REJECT;
871 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
872 	/*
873 	 * Perform the kref_put now if se_cmd has already been setup by
874 	 * scsit_setup_scsi_cmd()
875 	 */
876 	if (cmd->se_cmd.se_tfo != NULL) {
877 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
878 		target_put_sess_cmd(&cmd->se_cmd);
879 	}
880 	return -1;
881 }
882 
883 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
884 				 unsigned char *buf)
885 {
886 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
887 }
888 
889 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
890 {
891 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
892 }
893 EXPORT_SYMBOL(iscsit_reject_cmd);
894 
895 /*
896  * Map some portion of the allocated scatterlist to an iovec, suitable for
897  * kernel sockets to copy data in/out.
898  */
899 static int iscsit_map_iovec(
900 	struct iscsi_cmd *cmd,
901 	struct kvec *iov,
902 	u32 data_offset,
903 	u32 data_length)
904 {
905 	u32 i = 0;
906 	struct scatterlist *sg;
907 	unsigned int page_off;
908 
909 	/*
910 	 * We know each entry in t_data_sg contains a page.
911 	 */
912 	u32 ent = data_offset / PAGE_SIZE;
913 
914 	if (ent >= cmd->se_cmd.t_data_nents) {
915 		pr_err("Initial page entry out-of-bounds\n");
916 		return -1;
917 	}
918 
919 	sg = &cmd->se_cmd.t_data_sg[ent];
920 	page_off = (data_offset % PAGE_SIZE);
921 
922 	cmd->first_data_sg = sg;
923 	cmd->first_data_sg_off = page_off;
924 
925 	while (data_length) {
926 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
927 
928 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
929 		iov[i].iov_len = cur_len;
930 
931 		data_length -= cur_len;
932 		page_off = 0;
933 		sg = sg_next(sg);
934 		i++;
935 	}
936 
937 	cmd->kmapped_nents = i;
938 
939 	return i;
940 }
941 
942 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
943 {
944 	u32 i;
945 	struct scatterlist *sg;
946 
947 	sg = cmd->first_data_sg;
948 
949 	for (i = 0; i < cmd->kmapped_nents; i++)
950 		kunmap(sg_page(&sg[i]));
951 }
952 
953 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
954 {
955 	LIST_HEAD(ack_list);
956 	struct iscsi_cmd *cmd, *cmd_p;
957 
958 	conn->exp_statsn = exp_statsn;
959 
960 	if (conn->sess->sess_ops->RDMAExtensions)
961 		return;
962 
963 	spin_lock_bh(&conn->cmd_lock);
964 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
965 		spin_lock(&cmd->istate_lock);
966 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
967 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
968 			cmd->i_state = ISTATE_REMOVE;
969 			spin_unlock(&cmd->istate_lock);
970 			list_move_tail(&cmd->i_conn_node, &ack_list);
971 			continue;
972 		}
973 		spin_unlock(&cmd->istate_lock);
974 	}
975 	spin_unlock_bh(&conn->cmd_lock);
976 
977 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
978 		list_del_init(&cmd->i_conn_node);
979 		iscsit_free_cmd(cmd, false);
980 	}
981 }
982 
983 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
984 {
985 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
986 
987 	iov_count += ISCSI_IOV_DATA_BUFFER;
988 
989 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
990 	if (!cmd->iov_data) {
991 		pr_err("Unable to allocate cmd->iov_data\n");
992 		return -ENOMEM;
993 	}
994 
995 	cmd->orig_iov_data_count = iov_count;
996 	return 0;
997 }
998 
999 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1000 			  unsigned char *buf)
1001 {
1002 	int data_direction, payload_length;
1003 	struct iscsi_scsi_req *hdr;
1004 	int iscsi_task_attr;
1005 	int sam_task_attr;
1006 
1007 	atomic_long_inc(&conn->sess->cmd_pdus);
1008 
1009 	hdr			= (struct iscsi_scsi_req *) buf;
1010 	payload_length		= ntoh24(hdr->dlength);
1011 
1012 	/* FIXME; Add checks for AdditionalHeaderSegment */
1013 
1014 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1015 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1016 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1017 				" not set. Bad iSCSI Initiator.\n");
1018 		return iscsit_add_reject_cmd(cmd,
1019 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1020 	}
1021 
1022 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1023 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1024 		/*
1025 		 * From RFC-3720 Section 10.3.1:
1026 		 *
1027 		 * "Either or both of R and W MAY be 1 when either the
1028 		 *  Expected Data Transfer Length and/or Bidirectional Read
1029 		 *  Expected Data Transfer Length are 0"
1030 		 *
1031 		 * For this case, go ahead and clear the unnecssary bits
1032 		 * to avoid any confusion with ->data_direction.
1033 		 */
1034 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1035 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1036 
1037 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1038 			" set when Expected Data Transfer Length is 0 for"
1039 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1040 	}
1041 
1042 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1043 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1044 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1045 			" MUST be set if Expected Data Transfer Length is not 0."
1046 			" Bad iSCSI Initiator\n");
1047 		return iscsit_add_reject_cmd(cmd,
1048 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1049 	}
1050 
1051 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1052 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1053 		pr_err("Bidirectional operations not supported!\n");
1054 		return iscsit_add_reject_cmd(cmd,
1055 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1056 	}
1057 
1058 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1059 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1060 				" Scsi Command PDU.\n");
1061 		return iscsit_add_reject_cmd(cmd,
1062 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1063 	}
1064 
1065 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1066 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1067 			" protocol error.\n", payload_length);
1068 		return iscsit_add_reject_cmd(cmd,
1069 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1070 	}
1071 
1072 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1073 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1074 		pr_err("Expected Data Transfer Length and Length of"
1075 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1076 			" bit is not set protocol error\n");
1077 		return iscsit_add_reject_cmd(cmd,
1078 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1079 	}
1080 
1081 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1082 		pr_err("DataSegmentLength: %u is greater than"
1083 			" EDTL: %u, protocol error.\n", payload_length,
1084 				hdr->data_length);
1085 		return iscsit_add_reject_cmd(cmd,
1086 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1087 	}
1088 
1089 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1090 		pr_err("DataSegmentLength: %u is greater than"
1091 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1092 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1093 		return iscsit_add_reject_cmd(cmd,
1094 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1095 	}
1096 
1097 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1098 		pr_err("DataSegmentLength: %u is greater than"
1099 			" FirstBurstLength: %u, protocol error.\n",
1100 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1101 		return iscsit_add_reject_cmd(cmd,
1102 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1103 	}
1104 
1105 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1106 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1107 			  DMA_NONE;
1108 
1109 	cmd->data_direction = data_direction;
1110 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1111 	/*
1112 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1113 	 */
1114 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1115 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1116 		sam_task_attr = TCM_SIMPLE_TAG;
1117 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1118 		sam_task_attr = TCM_ORDERED_TAG;
1119 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1120 		sam_task_attr = TCM_HEAD_TAG;
1121 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1122 		sam_task_attr = TCM_ACA_TAG;
1123 	else {
1124 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1125 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1126 		sam_task_attr = TCM_SIMPLE_TAG;
1127 	}
1128 
1129 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1130 	cmd->i_state		= ISTATE_NEW_CMD;
1131 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1132 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1133 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1134 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1135 	if (cmd->unsolicited_data)
1136 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1137 
1138 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1139 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1140 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1141 	else
1142 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1143 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1144 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1145 	cmd->first_burst_len	= payload_length;
1146 
1147 	if (!conn->sess->sess_ops->RDMAExtensions &&
1148 	     cmd->data_direction == DMA_FROM_DEVICE) {
1149 		struct iscsi_datain_req *dr;
1150 
1151 		dr = iscsit_allocate_datain_req();
1152 		if (!dr)
1153 			return iscsit_add_reject_cmd(cmd,
1154 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1155 
1156 		iscsit_attach_datain_req(cmd, dr);
1157 	}
1158 
1159 	/*
1160 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1161 	 */
1162 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1163 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1164 			cmd->data_direction, sam_task_attr,
1165 			cmd->sense_buffer + 2);
1166 
1167 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1168 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1169 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1170 		conn->cid);
1171 
1172 	target_get_sess_cmd(&cmd->se_cmd, true);
1173 
1174 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
1175 						     scsilun_to_int(&hdr->lun));
1176 	if (cmd->sense_reason)
1177 		goto attach_cmd;
1178 
1179 	/* only used for printks or comparing with ->ref_task_tag */
1180 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1181 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
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 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1192 		return iscsit_add_reject_cmd(cmd,
1193 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1194 	}
1195 
1196 attach_cmd:
1197 	spin_lock_bh(&conn->cmd_lock);
1198 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1199 	spin_unlock_bh(&conn->cmd_lock);
1200 	/*
1201 	 * Check if we need to delay processing because of ALUA
1202 	 * Active/NonOptimized primary access state..
1203 	 */
1204 	core_alua_check_nonop_delay(&cmd->se_cmd);
1205 
1206 	return 0;
1207 }
1208 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1209 
1210 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1211 {
1212 	iscsit_set_dataout_sequence_values(cmd);
1213 
1214 	spin_lock_bh(&cmd->dataout_timeout_lock);
1215 	iscsit_start_dataout_timer(cmd, cmd->conn);
1216 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1217 }
1218 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1219 
1220 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1221 			    struct iscsi_scsi_req *hdr)
1222 {
1223 	int cmdsn_ret = 0;
1224 	/*
1225 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1226 	 * the Immediate Bit is not set, and no Immediate
1227 	 * Data is attached.
1228 	 *
1229 	 * A PDU/CmdSN carrying Immediate Data can only
1230 	 * be processed after the DataCRC has passed.
1231 	 * If the DataCRC fails, the CmdSN MUST NOT
1232 	 * be acknowledged. (See below)
1233 	 */
1234 	if (!cmd->immediate_data) {
1235 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1236 					(unsigned char *)hdr, hdr->cmdsn);
1237 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1238 			return -1;
1239 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1240 			target_put_sess_cmd(&cmd->se_cmd);
1241 			return 0;
1242 		}
1243 	}
1244 
1245 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1246 
1247 	/*
1248 	 * If no Immediate Data is attached, it's OK to return now.
1249 	 */
1250 	if (!cmd->immediate_data) {
1251 		if (!cmd->sense_reason && cmd->unsolicited_data)
1252 			iscsit_set_unsoliticed_dataout(cmd);
1253 		if (!cmd->sense_reason)
1254 			return 0;
1255 
1256 		target_put_sess_cmd(&cmd->se_cmd);
1257 		return 0;
1258 	}
1259 
1260 	/*
1261 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1262 	 * execution.  These exceptions are processed in CmdSN order using
1263 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1264 	 */
1265 	if (cmd->sense_reason) {
1266 		if (cmd->reject_reason)
1267 			return 0;
1268 
1269 		return 1;
1270 	}
1271 	/*
1272 	 * Call directly into transport_generic_new_cmd() to perform
1273 	 * the backend memory allocation.
1274 	 */
1275 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1276 	if (cmd->sense_reason)
1277 		return 1;
1278 
1279 	return 0;
1280 }
1281 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1282 
1283 static int
1284 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1285 			  bool dump_payload)
1286 {
1287 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1288 	/*
1289 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1290 	 */
1291 	if (dump_payload)
1292 		goto after_immediate_data;
1293 
1294 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1295 					cmd->first_burst_len);
1296 after_immediate_data:
1297 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1298 		/*
1299 		 * A PDU/CmdSN carrying Immediate Data passed
1300 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1301 		 * Immediate Bit is not set.
1302 		 */
1303 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1304 					(unsigned char *)hdr, hdr->cmdsn);
1305 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1306 			return -1;
1307 
1308 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1309 			int rc;
1310 
1311 			rc = iscsit_dump_data_payload(cmd->conn,
1312 						      cmd->first_burst_len, 1);
1313 			target_put_sess_cmd(&cmd->se_cmd);
1314 			return rc;
1315 		} else if (cmd->unsolicited_data)
1316 			iscsit_set_unsoliticed_dataout(cmd);
1317 
1318 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1319 		/*
1320 		 * Immediate Data failed DataCRC and ERL>=1,
1321 		 * silently drop this PDU and let the initiator
1322 		 * plug the CmdSN gap.
1323 		 *
1324 		 * FIXME: Send Unsolicited NOPIN with reserved
1325 		 * TTT here to help the initiator figure out
1326 		 * the missing CmdSN, although they should be
1327 		 * intelligent enough to determine the missing
1328 		 * CmdSN and issue a retry to plug the sequence.
1329 		 */
1330 		cmd->i_state = ISTATE_REMOVE;
1331 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1332 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1333 		return -1;
1334 
1335 	return 0;
1336 }
1337 
1338 static int
1339 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1340 			   unsigned char *buf)
1341 {
1342 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1343 	int rc, immed_data;
1344 	bool dump_payload = false;
1345 
1346 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1347 	if (rc < 0)
1348 		return 0;
1349 	/*
1350 	 * Allocation iovecs needed for struct socket operations for
1351 	 * traditional iSCSI block I/O.
1352 	 */
1353 	if (iscsit_allocate_iovecs(cmd) < 0) {
1354 		return iscsit_reject_cmd(cmd,
1355 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1356 	}
1357 	immed_data = cmd->immediate_data;
1358 
1359 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1360 	if (rc < 0)
1361 		return rc;
1362 	else if (rc > 0)
1363 		dump_payload = true;
1364 
1365 	if (!immed_data)
1366 		return 0;
1367 
1368 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1369 }
1370 
1371 static u32 iscsit_do_crypto_hash_sg(
1372 	struct ahash_request *hash,
1373 	struct iscsi_cmd *cmd,
1374 	u32 data_offset,
1375 	u32 data_length,
1376 	u32 padding,
1377 	u8 *pad_bytes)
1378 {
1379 	u32 data_crc;
1380 	struct scatterlist *sg;
1381 	unsigned int page_off;
1382 
1383 	crypto_ahash_init(hash);
1384 
1385 	sg = cmd->first_data_sg;
1386 	page_off = cmd->first_data_sg_off;
1387 
1388 	while (data_length) {
1389 		u32 cur_len = min_t(u32, data_length, (sg->length - page_off));
1390 
1391 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1392 		crypto_ahash_update(hash);
1393 
1394 		data_length -= cur_len;
1395 		page_off = 0;
1396 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1397 		sg = sg_next(sg);
1398 	}
1399 
1400 	if (padding) {
1401 		struct scatterlist pad_sg;
1402 
1403 		sg_init_one(&pad_sg, pad_bytes, padding);
1404 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1405 					padding);
1406 		crypto_ahash_finup(hash);
1407 	} else {
1408 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1409 		crypto_ahash_final(hash);
1410 	}
1411 
1412 	return data_crc;
1413 }
1414 
1415 static void iscsit_do_crypto_hash_buf(
1416 	struct ahash_request *hash,
1417 	const void *buf,
1418 	u32 payload_length,
1419 	u32 padding,
1420 	u8 *pad_bytes,
1421 	u8 *data_crc)
1422 {
1423 	struct scatterlist sg[2];
1424 
1425 	sg_init_table(sg, ARRAY_SIZE(sg));
1426 	sg_set_buf(sg, buf, payload_length);
1427 	sg_set_buf(sg + 1, pad_bytes, padding);
1428 
1429 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1430 
1431 	crypto_ahash_digest(hash);
1432 }
1433 
1434 int
1435 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1436 			  struct iscsi_cmd **out_cmd)
1437 {
1438 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1439 	struct iscsi_cmd *cmd = NULL;
1440 	struct se_cmd *se_cmd;
1441 	u32 payload_length = ntoh24(hdr->dlength);
1442 	int rc;
1443 
1444 	if (!payload_length) {
1445 		pr_warn("DataOUT payload is ZERO, ignoring.\n");
1446 		return 0;
1447 	}
1448 
1449 	/* iSCSI write */
1450 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1451 
1452 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1453 		pr_err("DataSegmentLength: %u is greater than"
1454 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1455 			conn->conn_ops->MaxXmitDataSegmentLength);
1456 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1457 					 buf);
1458 	}
1459 
1460 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1461 			payload_length);
1462 	if (!cmd)
1463 		return 0;
1464 
1465 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1466 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1467 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1468 		payload_length, conn->cid);
1469 
1470 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1471 		pr_err("Command ITT: 0x%08x received DataOUT after"
1472 			" last DataOUT received, dumping payload\n",
1473 			cmd->init_task_tag);
1474 		return iscsit_dump_data_payload(conn, payload_length, 1);
1475 	}
1476 
1477 	if (cmd->data_direction != DMA_TO_DEVICE) {
1478 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1479 			" NON-WRITE command.\n", cmd->init_task_tag);
1480 		return iscsit_dump_data_payload(conn, payload_length, 1);
1481 	}
1482 	se_cmd = &cmd->se_cmd;
1483 	iscsit_mod_dataout_timer(cmd);
1484 
1485 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1486 		pr_err("DataOut Offset: %u, Length %u greater than"
1487 			" iSCSI Command EDTL %u, protocol error.\n",
1488 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1489 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1490 	}
1491 
1492 	if (cmd->unsolicited_data) {
1493 		int dump_unsolicited_data = 0;
1494 
1495 		if (conn->sess->sess_ops->InitialR2T) {
1496 			pr_err("Received unexpected unsolicited data"
1497 				" while InitialR2T=Yes, protocol error.\n");
1498 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1499 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1500 			return -1;
1501 		}
1502 		/*
1503 		 * Special case for dealing with Unsolicited DataOUT
1504 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1505 		 * failures;
1506 		 */
1507 
1508 		/* Something's amiss if we're not in WRITE_PENDING state... */
1509 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1510 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1511 			dump_unsolicited_data = 1;
1512 
1513 		if (dump_unsolicited_data) {
1514 			/*
1515 			 * Check if a delayed TASK_ABORTED status needs to
1516 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1517 			 * received with the unsolicited data out.
1518 			 */
1519 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1520 				iscsit_stop_dataout_timer(cmd);
1521 
1522 			transport_check_aborted_status(se_cmd,
1523 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1524 			return iscsit_dump_data_payload(conn, payload_length, 1);
1525 		}
1526 	} else {
1527 		/*
1528 		 * For the normal solicited data path:
1529 		 *
1530 		 * Check for a delayed TASK_ABORTED status and dump any
1531 		 * incoming data out payload if one exists.  Also, when the
1532 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1533 		 * data out sequence, we decrement outstanding_r2ts.  Once
1534 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1535 		 * TASK_ABORTED status.
1536 		 */
1537 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1538 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1539 				if (--cmd->outstanding_r2ts < 1) {
1540 					iscsit_stop_dataout_timer(cmd);
1541 					transport_check_aborted_status(
1542 							se_cmd, 1);
1543 				}
1544 
1545 			return iscsit_dump_data_payload(conn, payload_length, 1);
1546 		}
1547 	}
1548 	/*
1549 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1550 	 * within-command recovery checks before receiving the payload.
1551 	 */
1552 	rc = iscsit_check_pre_dataout(cmd, buf);
1553 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1554 		return 0;
1555 	else if (rc == DATAOUT_CANNOT_RECOVER)
1556 		return -1;
1557 
1558 	*out_cmd = cmd;
1559 	return 0;
1560 }
1561 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1562 
1563 static int
1564 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1565 		   struct iscsi_data *hdr)
1566 {
1567 	struct kvec *iov;
1568 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1569 	u32 payload_length = ntoh24(hdr->dlength);
1570 	int iov_ret, data_crc_failed = 0;
1571 
1572 	rx_size += payload_length;
1573 	iov = &cmd->iov_data[0];
1574 
1575 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1576 				   payload_length);
1577 	if (iov_ret < 0)
1578 		return -1;
1579 
1580 	iov_count += iov_ret;
1581 
1582 	padding = ((-payload_length) & 3);
1583 	if (padding != 0) {
1584 		iov[iov_count].iov_base	= cmd->pad_bytes;
1585 		iov[iov_count++].iov_len = padding;
1586 		rx_size += padding;
1587 		pr_debug("Receiving %u padding bytes.\n", padding);
1588 	}
1589 
1590 	if (conn->conn_ops->DataDigest) {
1591 		iov[iov_count].iov_base = &checksum;
1592 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1593 		rx_size += ISCSI_CRC_LEN;
1594 	}
1595 
1596 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1597 
1598 	iscsit_unmap_iovec(cmd);
1599 
1600 	if (rx_got != rx_size)
1601 		return -1;
1602 
1603 	if (conn->conn_ops->DataDigest) {
1604 		u32 data_crc;
1605 
1606 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1607 						    be32_to_cpu(hdr->offset),
1608 						    payload_length, padding,
1609 						    cmd->pad_bytes);
1610 
1611 		if (checksum != data_crc) {
1612 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1613 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1614 				" does not match computed 0x%08x\n",
1615 				hdr->itt, hdr->offset, payload_length,
1616 				hdr->datasn, checksum, data_crc);
1617 			data_crc_failed = 1;
1618 		} else {
1619 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1620 				" %u bytes of Data Out\n", checksum,
1621 				payload_length);
1622 		}
1623 	}
1624 
1625 	return data_crc_failed;
1626 }
1627 
1628 int
1629 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1630 			     bool data_crc_failed)
1631 {
1632 	struct iscsi_conn *conn = cmd->conn;
1633 	int rc, ooo_cmdsn;
1634 	/*
1635 	 * Increment post receive data and CRC values or perform
1636 	 * within-command recovery.
1637 	 */
1638 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1639 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1640 		return 0;
1641 	else if (rc == DATAOUT_SEND_R2T) {
1642 		iscsit_set_dataout_sequence_values(cmd);
1643 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1644 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1645 		/*
1646 		 * Handle extra special case for out of order
1647 		 * Unsolicited Data Out.
1648 		 */
1649 		spin_lock_bh(&cmd->istate_lock);
1650 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1651 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1652 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1653 		spin_unlock_bh(&cmd->istate_lock);
1654 
1655 		iscsit_stop_dataout_timer(cmd);
1656 		if (ooo_cmdsn)
1657 			return 0;
1658 		target_execute_cmd(&cmd->se_cmd);
1659 		return 0;
1660 	} else /* DATAOUT_CANNOT_RECOVER */
1661 		return -1;
1662 
1663 	return 0;
1664 }
1665 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1666 
1667 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1668 {
1669 	struct iscsi_cmd *cmd = NULL;
1670 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1671 	int rc;
1672 	bool data_crc_failed = false;
1673 
1674 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1675 	if (rc < 0)
1676 		return 0;
1677 	else if (!cmd)
1678 		return 0;
1679 
1680 	rc = iscsit_get_dataout(conn, cmd, hdr);
1681 	if (rc < 0)
1682 		return rc;
1683 	else if (rc > 0)
1684 		data_crc_failed = true;
1685 
1686 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1687 }
1688 
1689 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1690 			 struct iscsi_nopout *hdr)
1691 {
1692 	u32 payload_length = ntoh24(hdr->dlength);
1693 
1694 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1695 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1696 		if (!cmd)
1697 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1698 						 (unsigned char *)hdr);
1699 
1700 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1701 					 (unsigned char *)hdr);
1702 	}
1703 
1704 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1705 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1706 			" not set, protocol error.\n");
1707 		if (!cmd)
1708 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1709 						 (unsigned char *)hdr);
1710 
1711 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1712 					 (unsigned char *)hdr);
1713 	}
1714 
1715 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1716 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1717 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1718 			" error.\n", payload_length,
1719 			conn->conn_ops->MaxXmitDataSegmentLength);
1720 		if (!cmd)
1721 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1722 						 (unsigned char *)hdr);
1723 
1724 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1725 					 (unsigned char *)hdr);
1726 	}
1727 
1728 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1729 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1730 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1731 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1732 		payload_length);
1733 	/*
1734 	 * This is not a response to a Unsolicited NopIN, which means
1735 	 * it can either be a NOPOUT ping request (with a valid ITT),
1736 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1737 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1738 	 * can contain ping data.
1739 	 */
1740 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1741 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1742 		cmd->i_state		= ISTATE_SEND_NOPIN;
1743 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1744 						1 : 0);
1745 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1746 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1747 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1748 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1749 		cmd->data_direction	= DMA_NONE;
1750 	}
1751 
1752 	return 0;
1753 }
1754 EXPORT_SYMBOL(iscsit_setup_nop_out);
1755 
1756 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1757 			   struct iscsi_nopout *hdr)
1758 {
1759 	struct iscsi_cmd *cmd_p = NULL;
1760 	int cmdsn_ret = 0;
1761 	/*
1762 	 * Initiator is expecting a NopIN ping reply..
1763 	 */
1764 	if (hdr->itt != RESERVED_ITT) {
1765 		if (!cmd)
1766 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1767 						(unsigned char *)hdr);
1768 
1769 		spin_lock_bh(&conn->cmd_lock);
1770 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1771 		spin_unlock_bh(&conn->cmd_lock);
1772 
1773 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1774 
1775 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1776 			iscsit_add_cmd_to_response_queue(cmd, conn,
1777 							 cmd->i_state);
1778 			return 0;
1779 		}
1780 
1781 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1782 				(unsigned char *)hdr, hdr->cmdsn);
1783                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1784 			return 0;
1785 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1786 			return -1;
1787 
1788 		return 0;
1789 	}
1790 	/*
1791 	 * This was a response to a unsolicited NOPIN ping.
1792 	 */
1793 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1794 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1795 		if (!cmd_p)
1796 			return -EINVAL;
1797 
1798 		iscsit_stop_nopin_response_timer(conn);
1799 
1800 		cmd_p->i_state = ISTATE_REMOVE;
1801 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1802 
1803 		iscsit_start_nopin_timer(conn);
1804 		return 0;
1805 	}
1806 	/*
1807 	 * Otherwise, initiator is not expecting a NOPIN is response.
1808 	 * Just ignore for now.
1809 	 */
1810 
1811 	if (cmd)
1812 		iscsit_free_cmd(cmd, false);
1813 
1814         return 0;
1815 }
1816 EXPORT_SYMBOL(iscsit_process_nop_out);
1817 
1818 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1819 				 unsigned char *buf)
1820 {
1821 	unsigned char *ping_data = NULL;
1822 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1823 	struct kvec *iov = NULL;
1824 	u32 payload_length = ntoh24(hdr->dlength);
1825 	int ret;
1826 
1827 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1828 	if (ret < 0)
1829 		return 0;
1830 	/*
1831 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1832 	 */
1833 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1834 		u32 checksum, data_crc, padding = 0;
1835 		int niov = 0, rx_got, rx_size = payload_length;
1836 
1837 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1838 		if (!ping_data) {
1839 			pr_err("Unable to allocate memory for"
1840 				" NOPOUT ping data.\n");
1841 			ret = -1;
1842 			goto out;
1843 		}
1844 
1845 		iov = &cmd->iov_misc[0];
1846 		iov[niov].iov_base	= ping_data;
1847 		iov[niov++].iov_len	= payload_length;
1848 
1849 		padding = ((-payload_length) & 3);
1850 		if (padding != 0) {
1851 			pr_debug("Receiving %u additional bytes"
1852 				" for padding.\n", padding);
1853 			iov[niov].iov_base	= &cmd->pad_bytes;
1854 			iov[niov++].iov_len	= padding;
1855 			rx_size += padding;
1856 		}
1857 		if (conn->conn_ops->DataDigest) {
1858 			iov[niov].iov_base	= &checksum;
1859 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1860 			rx_size += ISCSI_CRC_LEN;
1861 		}
1862 
1863 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1864 		if (rx_got != rx_size) {
1865 			ret = -1;
1866 			goto out;
1867 		}
1868 
1869 		if (conn->conn_ops->DataDigest) {
1870 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
1871 					ping_data, payload_length,
1872 					padding, cmd->pad_bytes,
1873 					(u8 *)&data_crc);
1874 
1875 			if (checksum != data_crc) {
1876 				pr_err("Ping data CRC32C DataDigest"
1877 				" 0x%08x does not match computed 0x%08x\n",
1878 					checksum, data_crc);
1879 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1880 					pr_err("Unable to recover from"
1881 					" NOPOUT Ping DataCRC failure while in"
1882 						" ERL=0.\n");
1883 					ret = -1;
1884 					goto out;
1885 				} else {
1886 					/*
1887 					 * Silently drop this PDU and let the
1888 					 * initiator plug the CmdSN gap.
1889 					 */
1890 					pr_debug("Dropping NOPOUT"
1891 					" Command CmdSN: 0x%08x due to"
1892 					" DataCRC error.\n", hdr->cmdsn);
1893 					ret = 0;
1894 					goto out;
1895 				}
1896 			} else {
1897 				pr_debug("Got CRC32C DataDigest"
1898 				" 0x%08x for %u bytes of ping data.\n",
1899 					checksum, payload_length);
1900 			}
1901 		}
1902 
1903 		ping_data[payload_length] = '\0';
1904 		/*
1905 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1906 		 */
1907 		cmd->buf_ptr = ping_data;
1908 		cmd->buf_ptr_size = payload_length;
1909 
1910 		pr_debug("Got %u bytes of NOPOUT ping"
1911 			" data.\n", payload_length);
1912 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1913 	}
1914 
1915 	return iscsit_process_nop_out(conn, cmd, hdr);
1916 out:
1917 	if (cmd)
1918 		iscsit_free_cmd(cmd, false);
1919 
1920 	kfree(ping_data);
1921 	return ret;
1922 }
1923 
1924 int
1925 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1926 			   unsigned char *buf)
1927 {
1928 	struct se_tmr_req *se_tmr;
1929 	struct iscsi_tmr_req *tmr_req;
1930 	struct iscsi_tm *hdr;
1931 	int out_of_order_cmdsn = 0, ret;
1932 	bool sess_ref = false;
1933 	u8 function;
1934 
1935 	hdr			= (struct iscsi_tm *) buf;
1936 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1937 	function = hdr->flags;
1938 
1939 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1940 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1941 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1942 		hdr->rtt, hdr->refcmdsn, conn->cid);
1943 
1944 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1945 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1946 	     hdr->rtt != RESERVED_ITT)) {
1947 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1948 		hdr->rtt = RESERVED_ITT;
1949 	}
1950 
1951 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1952 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1953 		pr_err("Task Management Request TASK_REASSIGN not"
1954 			" issued as immediate command, bad iSCSI Initiator"
1955 				"implementation\n");
1956 		return iscsit_add_reject_cmd(cmd,
1957 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1958 	}
1959 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1960 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1961 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1962 
1963 	cmd->data_direction = DMA_NONE;
1964 
1965 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1966 	if (!cmd->tmr_req) {
1967 		pr_err("Unable to allocate memory for"
1968 			" Task Management command!\n");
1969 		return iscsit_add_reject_cmd(cmd,
1970 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1971 					     buf);
1972 	}
1973 
1974 	/*
1975 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1976 	 * LIO-Target $FABRIC_MOD
1977 	 */
1978 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1979 
1980 		u8 tcm_function;
1981 		int ret;
1982 
1983 		transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1984 				      conn->sess->se_sess, 0, DMA_NONE,
1985 				      TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
1986 
1987 		target_get_sess_cmd(&cmd->se_cmd, true);
1988 		sess_ref = true;
1989 
1990 		switch (function) {
1991 		case ISCSI_TM_FUNC_ABORT_TASK:
1992 			tcm_function = TMR_ABORT_TASK;
1993 			break;
1994 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1995 			tcm_function = TMR_ABORT_TASK_SET;
1996 			break;
1997 		case ISCSI_TM_FUNC_CLEAR_ACA:
1998 			tcm_function = TMR_CLEAR_ACA;
1999 			break;
2000 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2001 			tcm_function = TMR_CLEAR_TASK_SET;
2002 			break;
2003 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2004 			tcm_function = TMR_LUN_RESET;
2005 			break;
2006 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2007 			tcm_function = TMR_TARGET_WARM_RESET;
2008 			break;
2009 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2010 			tcm_function = TMR_TARGET_COLD_RESET;
2011 			break;
2012 		default:
2013 			pr_err("Unknown iSCSI TMR Function:"
2014 			       " 0x%02x\n", function);
2015 			return iscsit_add_reject_cmd(cmd,
2016 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2017 		}
2018 
2019 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
2020 					 tcm_function, GFP_KERNEL);
2021 		if (ret < 0)
2022 			return iscsit_add_reject_cmd(cmd,
2023 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2024 
2025 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2026 	}
2027 
2028 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2029 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2030 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2031 	cmd->init_task_tag	= hdr->itt;
2032 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2033 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2034 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2035 	se_tmr			= cmd->se_cmd.se_tmr_req;
2036 	tmr_req			= cmd->tmr_req;
2037 	/*
2038 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2039 	 */
2040 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2041 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
2042 					       scsilun_to_int(&hdr->lun));
2043 		if (ret < 0) {
2044 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2045 			goto attach;
2046 		}
2047 	}
2048 
2049 	switch (function) {
2050 	case ISCSI_TM_FUNC_ABORT_TASK:
2051 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2052 		if (se_tmr->response)
2053 			goto attach;
2054 		break;
2055 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2056 	case ISCSI_TM_FUNC_CLEAR_ACA:
2057 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2058 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2059 		break;
2060 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2061 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2062 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2063 			goto attach;
2064 		}
2065 		break;
2066 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2067 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2068 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2069 			goto attach;
2070 		}
2071 		break;
2072 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2073 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2074 		/*
2075 		 * Perform sanity checks on the ExpDataSN only if the
2076 		 * TASK_REASSIGN was successful.
2077 		 */
2078 		if (se_tmr->response)
2079 			break;
2080 
2081 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2082 			return iscsit_add_reject_cmd(cmd,
2083 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2084 		break;
2085 	default:
2086 		pr_err("Unknown TMR function: 0x%02x, protocol"
2087 			" error.\n", function);
2088 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2089 		goto attach;
2090 	}
2091 
2092 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2093 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2094 		se_tmr->call_transport = 1;
2095 attach:
2096 	spin_lock_bh(&conn->cmd_lock);
2097 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2098 	spin_unlock_bh(&conn->cmd_lock);
2099 
2100 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2101 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2102 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
2103 			out_of_order_cmdsn = 1;
2104 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2105 			return 0;
2106 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2107 			return -1;
2108 	}
2109 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2110 
2111 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2112 		return 0;
2113 	/*
2114 	 * Found the referenced task, send to transport for processing.
2115 	 */
2116 	if (se_tmr->call_transport)
2117 		return transport_generic_handle_tmr(&cmd->se_cmd);
2118 
2119 	/*
2120 	 * Could not find the referenced LUN, task, or Task Management
2121 	 * command not authorized or supported.  Change state and
2122 	 * let the tx_thread send the response.
2123 	 *
2124 	 * For connection recovery, this is also the default action for
2125 	 * TMR TASK_REASSIGN.
2126 	 */
2127 	if (sess_ref) {
2128 		pr_debug("Handle TMR, using sess_ref=true check\n");
2129 		target_put_sess_cmd(&cmd->se_cmd);
2130 	}
2131 
2132 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2133 	return 0;
2134 }
2135 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2136 
2137 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2138 int
2139 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2140 		      struct iscsi_text *hdr)
2141 {
2142 	u32 payload_length = ntoh24(hdr->dlength);
2143 
2144 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2145 		pr_err("Unable to accept text parameter length: %u"
2146 			"greater than MaxXmitDataSegmentLength %u.\n",
2147 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2148 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2149 					 (unsigned char *)hdr);
2150 	}
2151 
2152 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2153 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2154 		pr_err("Multi sequence text commands currently not supported\n");
2155 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2156 					(unsigned char *)hdr);
2157 	}
2158 
2159 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2160 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2161 		hdr->exp_statsn, payload_length);
2162 
2163 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2164 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2165 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2166 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2167 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2168 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2169 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2170 	cmd->data_direction	= DMA_NONE;
2171 	cmd->text_in_ptr	= NULL;
2172 
2173 	return 0;
2174 }
2175 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2176 
2177 int
2178 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2179 			struct iscsi_text *hdr)
2180 {
2181 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2182 	int cmdsn_ret;
2183 
2184 	if (!text_in) {
2185 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2186 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2187 			pr_err("Unable to locate text_in buffer for sendtargets"
2188 			       " discovery\n");
2189 			goto reject;
2190 		}
2191 		goto empty_sendtargets;
2192 	}
2193 	if (strncmp("SendTargets", text_in, 11) != 0) {
2194 		pr_err("Received Text Data that is not"
2195 			" SendTargets, cannot continue.\n");
2196 		goto reject;
2197 	}
2198 	text_ptr = strchr(text_in, '=');
2199 	if (!text_ptr) {
2200 		pr_err("No \"=\" separator found in Text Data,"
2201 			"  cannot continue.\n");
2202 		goto reject;
2203 	}
2204 	if (!strncmp("=All", text_ptr, 4)) {
2205 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2206 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2207 		   !strncmp("=eui.", text_ptr, 5)) {
2208 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2209 	} else {
2210 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2211 		goto reject;
2212 	}
2213 
2214 	spin_lock_bh(&conn->cmd_lock);
2215 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2216 	spin_unlock_bh(&conn->cmd_lock);
2217 
2218 empty_sendtargets:
2219 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2220 
2221 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2222 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2223 				(unsigned char *)hdr, hdr->cmdsn);
2224 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2225 			return -1;
2226 
2227 		return 0;
2228 	}
2229 
2230 	return iscsit_execute_cmd(cmd, 0);
2231 
2232 reject:
2233 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2234 				 (unsigned char *)hdr);
2235 }
2236 EXPORT_SYMBOL(iscsit_process_text_cmd);
2237 
2238 static int
2239 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2240 		       unsigned char *buf)
2241 {
2242 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2243 	char *text_in = NULL;
2244 	u32 payload_length = ntoh24(hdr->dlength);
2245 	int rx_size, rc;
2246 
2247 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2248 	if (rc < 0)
2249 		return 0;
2250 
2251 	rx_size = payload_length;
2252 	if (payload_length) {
2253 		u32 checksum = 0, data_crc = 0;
2254 		u32 padding = 0, pad_bytes = 0;
2255 		int niov = 0, rx_got;
2256 		struct kvec iov[3];
2257 
2258 		text_in = kzalloc(payload_length, GFP_KERNEL);
2259 		if (!text_in) {
2260 			pr_err("Unable to allocate memory for"
2261 				" incoming text parameters\n");
2262 			goto reject;
2263 		}
2264 		cmd->text_in_ptr = text_in;
2265 
2266 		memset(iov, 0, 3 * sizeof(struct kvec));
2267 		iov[niov].iov_base	= text_in;
2268 		iov[niov++].iov_len	= payload_length;
2269 
2270 		padding = ((-payload_length) & 3);
2271 		if (padding != 0) {
2272 			iov[niov].iov_base = &pad_bytes;
2273 			iov[niov++].iov_len  = padding;
2274 			rx_size += padding;
2275 			pr_debug("Receiving %u additional bytes"
2276 					" for padding.\n", padding);
2277 		}
2278 		if (conn->conn_ops->DataDigest) {
2279 			iov[niov].iov_base	= &checksum;
2280 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2281 			rx_size += ISCSI_CRC_LEN;
2282 		}
2283 
2284 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2285 		if (rx_got != rx_size)
2286 			goto reject;
2287 
2288 		if (conn->conn_ops->DataDigest) {
2289 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2290 					text_in, payload_length,
2291 					padding, (u8 *)&pad_bytes,
2292 					(u8 *)&data_crc);
2293 
2294 			if (checksum != data_crc) {
2295 				pr_err("Text data CRC32C DataDigest"
2296 					" 0x%08x does not match computed"
2297 					" 0x%08x\n", checksum, data_crc);
2298 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2299 					pr_err("Unable to recover from"
2300 					" Text Data digest failure while in"
2301 						" ERL=0.\n");
2302 					goto reject;
2303 				} else {
2304 					/*
2305 					 * Silently drop this PDU and let the
2306 					 * initiator plug the CmdSN gap.
2307 					 */
2308 					pr_debug("Dropping Text"
2309 					" Command CmdSN: 0x%08x due to"
2310 					" DataCRC error.\n", hdr->cmdsn);
2311 					kfree(text_in);
2312 					return 0;
2313 				}
2314 			} else {
2315 				pr_debug("Got CRC32C DataDigest"
2316 					" 0x%08x for %u bytes of text data.\n",
2317 						checksum, payload_length);
2318 			}
2319 		}
2320 		text_in[payload_length - 1] = '\0';
2321 		pr_debug("Successfully read %d bytes of text"
2322 				" data.\n", payload_length);
2323 	}
2324 
2325 	return iscsit_process_text_cmd(conn, cmd, hdr);
2326 
2327 reject:
2328 	kfree(cmd->text_in_ptr);
2329 	cmd->text_in_ptr = NULL;
2330 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2331 }
2332 
2333 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2334 {
2335 	struct iscsi_conn *conn_p;
2336 	struct iscsi_session *sess = conn->sess;
2337 
2338 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2339 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2340 
2341 	atomic_set(&sess->session_logout, 1);
2342 	atomic_set(&conn->conn_logout_remove, 1);
2343 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2344 
2345 	iscsit_inc_conn_usage_count(conn);
2346 	iscsit_inc_session_usage_count(sess);
2347 
2348 	spin_lock_bh(&sess->conn_lock);
2349 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2350 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2351 			continue;
2352 
2353 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2354 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2355 	}
2356 	spin_unlock_bh(&sess->conn_lock);
2357 
2358 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2359 
2360 	return 0;
2361 }
2362 
2363 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2364 {
2365 	struct iscsi_conn *l_conn;
2366 	struct iscsi_session *sess = conn->sess;
2367 
2368 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2369 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2370 
2371 	/*
2372 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2373 	 * can arrive on a connection with a differing CID.
2374 	 */
2375 	if (conn->cid == cmd->logout_cid) {
2376 		spin_lock_bh(&conn->state_lock);
2377 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2378 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2379 
2380 		atomic_set(&conn->conn_logout_remove, 1);
2381 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2382 		iscsit_inc_conn_usage_count(conn);
2383 
2384 		spin_unlock_bh(&conn->state_lock);
2385 	} else {
2386 		/*
2387 		 * Handle all different cid CLOSECONNECTION requests in
2388 		 * iscsit_logout_post_handler_diffcid() as to give enough
2389 		 * time for any non immediate command's CmdSN to be
2390 		 * acknowledged on the connection in question.
2391 		 *
2392 		 * Here we simply make sure the CID is still around.
2393 		 */
2394 		l_conn = iscsit_get_conn_from_cid(sess,
2395 				cmd->logout_cid);
2396 		if (!l_conn) {
2397 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2398 			iscsit_add_cmd_to_response_queue(cmd, conn,
2399 					cmd->i_state);
2400 			return 0;
2401 		}
2402 
2403 		iscsit_dec_conn_usage_count(l_conn);
2404 	}
2405 
2406 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2407 
2408 	return 0;
2409 }
2410 
2411 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2412 {
2413 	struct iscsi_session *sess = conn->sess;
2414 
2415 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2416 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2417 
2418 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2419 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2420 			" while ERL!=2.\n");
2421 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2422 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2423 		return 0;
2424 	}
2425 
2426 	if (conn->cid == cmd->logout_cid) {
2427 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2428 			" with CID: %hu on CID: %hu, implementation error.\n",
2429 				cmd->logout_cid, conn->cid);
2430 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2431 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2432 		return 0;
2433 	}
2434 
2435 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2436 
2437 	return 0;
2438 }
2439 
2440 int
2441 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2442 			unsigned char *buf)
2443 {
2444 	int cmdsn_ret, logout_remove = 0;
2445 	u8 reason_code = 0;
2446 	struct iscsi_logout *hdr;
2447 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2448 
2449 	hdr			= (struct iscsi_logout *) buf;
2450 	reason_code		= (hdr->flags & 0x7f);
2451 
2452 	if (tiqn) {
2453 		spin_lock(&tiqn->logout_stats.lock);
2454 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2455 			tiqn->logout_stats.normal_logouts++;
2456 		else
2457 			tiqn->logout_stats.abnormal_logouts++;
2458 		spin_unlock(&tiqn->logout_stats.lock);
2459 	}
2460 
2461 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2462 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2463 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2464 		hdr->cid, conn->cid);
2465 
2466 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2467 		pr_err("Received logout request on connection that"
2468 			" is not in logged in state, ignoring request.\n");
2469 		iscsit_free_cmd(cmd, false);
2470 		return 0;
2471 	}
2472 
2473 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2474 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2475 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2476 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2477 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2478 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2479 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2480 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2481 	cmd->logout_reason      = reason_code;
2482 	cmd->data_direction     = DMA_NONE;
2483 
2484 	/*
2485 	 * We need to sleep in these cases (by returning 1) until the Logout
2486 	 * Response gets sent in the tx thread.
2487 	 */
2488 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2489 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2490 	    be16_to_cpu(hdr->cid) == conn->cid))
2491 		logout_remove = 1;
2492 
2493 	spin_lock_bh(&conn->cmd_lock);
2494 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2495 	spin_unlock_bh(&conn->cmd_lock);
2496 
2497 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2498 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2499 
2500 	/*
2501 	 * Immediate commands are executed, well, immediately.
2502 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2503 	 */
2504 	if (cmd->immediate_cmd) {
2505 		int ret = iscsit_execute_cmd(cmd, 0);
2506 
2507 		if (ret < 0)
2508 			return ret;
2509 	} else {
2510 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2511 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2512 			logout_remove = 0;
2513 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2514 			return -1;
2515 	}
2516 
2517 	return logout_remove;
2518 }
2519 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2520 
2521 int iscsit_handle_snack(
2522 	struct iscsi_conn *conn,
2523 	unsigned char *buf)
2524 {
2525 	struct iscsi_snack *hdr;
2526 
2527 	hdr			= (struct iscsi_snack *) buf;
2528 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2529 
2530 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2531 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2532 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2533 			hdr->begrun, hdr->runlength, conn->cid);
2534 
2535 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2536 		pr_err("Initiator sent SNACK request while in"
2537 			" ErrorRecoveryLevel=0.\n");
2538 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2539 					 buf);
2540 	}
2541 	/*
2542 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2543 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2544 	 */
2545 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2546 	case 0:
2547 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2548 			hdr->itt,
2549 			be32_to_cpu(hdr->ttt),
2550 			be32_to_cpu(hdr->begrun),
2551 			be32_to_cpu(hdr->runlength));
2552 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2553 		return iscsit_handle_status_snack(conn, hdr->itt,
2554 			be32_to_cpu(hdr->ttt),
2555 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2556 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2557 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2558 			be32_to_cpu(hdr->begrun),
2559 			be32_to_cpu(hdr->runlength));
2560 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2561 		/* FIXME: Support R-Data SNACK */
2562 		pr_err("R-Data SNACK Not Supported.\n");
2563 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2564 					 buf);
2565 	default:
2566 		pr_err("Unknown SNACK type 0x%02x, protocol"
2567 			" error.\n", hdr->flags & 0x0f);
2568 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2569 					 buf);
2570 	}
2571 
2572 	return 0;
2573 }
2574 EXPORT_SYMBOL(iscsit_handle_snack);
2575 
2576 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2577 {
2578 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2579 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2580 		wait_for_completion_interruptible_timeout(
2581 					&conn->rx_half_close_comp,
2582 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2583 	}
2584 }
2585 
2586 static int iscsit_handle_immediate_data(
2587 	struct iscsi_cmd *cmd,
2588 	struct iscsi_scsi_req *hdr,
2589 	u32 length)
2590 {
2591 	int iov_ret, rx_got = 0, rx_size = 0;
2592 	u32 checksum, iov_count = 0, padding = 0;
2593 	struct iscsi_conn *conn = cmd->conn;
2594 	struct kvec *iov;
2595 
2596 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2597 	if (iov_ret < 0)
2598 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2599 
2600 	rx_size = length;
2601 	iov_count = iov_ret;
2602 	iov = &cmd->iov_data[0];
2603 
2604 	padding = ((-length) & 3);
2605 	if (padding != 0) {
2606 		iov[iov_count].iov_base	= cmd->pad_bytes;
2607 		iov[iov_count++].iov_len = padding;
2608 		rx_size += padding;
2609 	}
2610 
2611 	if (conn->conn_ops->DataDigest) {
2612 		iov[iov_count].iov_base		= &checksum;
2613 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2614 		rx_size += ISCSI_CRC_LEN;
2615 	}
2616 
2617 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2618 
2619 	iscsit_unmap_iovec(cmd);
2620 
2621 	if (rx_got != rx_size) {
2622 		iscsit_rx_thread_wait_for_tcp(conn);
2623 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2624 	}
2625 
2626 	if (conn->conn_ops->DataDigest) {
2627 		u32 data_crc;
2628 
2629 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2630 						    cmd->write_data_done, length, padding,
2631 						    cmd->pad_bytes);
2632 
2633 		if (checksum != data_crc) {
2634 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2635 				" does not match computed 0x%08x\n", checksum,
2636 				data_crc);
2637 
2638 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2639 				pr_err("Unable to recover from"
2640 					" Immediate Data digest failure while"
2641 					" in ERL=0.\n");
2642 				iscsit_reject_cmd(cmd,
2643 						ISCSI_REASON_DATA_DIGEST_ERROR,
2644 						(unsigned char *)hdr);
2645 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2646 			} else {
2647 				iscsit_reject_cmd(cmd,
2648 						ISCSI_REASON_DATA_DIGEST_ERROR,
2649 						(unsigned char *)hdr);
2650 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2651 			}
2652 		} else {
2653 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2654 				" %u bytes of Immediate Data\n", checksum,
2655 				length);
2656 		}
2657 	}
2658 
2659 	cmd->write_data_done += length;
2660 
2661 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2662 		spin_lock_bh(&cmd->istate_lock);
2663 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2664 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2665 		spin_unlock_bh(&cmd->istate_lock);
2666 	}
2667 
2668 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2669 }
2670 
2671 /*
2672  *	Called with sess->conn_lock held.
2673  */
2674 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2675 	with active network interface */
2676 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2677 {
2678 	struct iscsi_cmd *cmd;
2679 	struct iscsi_conn *conn_p;
2680 	bool found = false;
2681 
2682 	/*
2683 	 * Only send a Asynchronous Message on connections whos network
2684 	 * interface is still functional.
2685 	 */
2686 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2687 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2688 			iscsit_inc_conn_usage_count(conn_p);
2689 			found = true;
2690 			break;
2691 		}
2692 	}
2693 
2694 	if (!found)
2695 		return;
2696 
2697 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2698 	if (!cmd) {
2699 		iscsit_dec_conn_usage_count(conn_p);
2700 		return;
2701 	}
2702 
2703 	cmd->logout_cid = conn->cid;
2704 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2705 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2706 
2707 	spin_lock_bh(&conn_p->cmd_lock);
2708 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2709 	spin_unlock_bh(&conn_p->cmd_lock);
2710 
2711 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2712 	iscsit_dec_conn_usage_count(conn_p);
2713 }
2714 
2715 static int iscsit_send_conn_drop_async_message(
2716 	struct iscsi_cmd *cmd,
2717 	struct iscsi_conn *conn)
2718 {
2719 	struct iscsi_async *hdr;
2720 
2721 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2722 
2723 	hdr			= (struct iscsi_async *) cmd->pdu;
2724 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2725 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2726 	cmd->init_task_tag	= RESERVED_ITT;
2727 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2728 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2729 	cmd->stat_sn		= conn->stat_sn++;
2730 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2731 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2732 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2733 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2734 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2735 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2736 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2737 
2738 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2739 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2740 			cmd->logout_cid, conn->cid);
2741 
2742 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2743 }
2744 
2745 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2746 {
2747 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2748 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2749 		wait_for_completion_interruptible_timeout(
2750 					&conn->tx_half_close_comp,
2751 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2752 	}
2753 }
2754 
2755 void
2756 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2757 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2758 			bool set_statsn)
2759 {
2760 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2761 	hdr->flags		= datain->flags;
2762 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2763 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2764 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2765 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2766 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2767 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2768 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2769 		}
2770 	}
2771 	hton24(hdr->dlength, datain->length);
2772 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2773 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2774 				(struct scsi_lun *)&hdr->lun);
2775 	else
2776 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2777 
2778 	hdr->itt		= cmd->init_task_tag;
2779 
2780 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2781 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2782 	else
2783 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2784 	if (set_statsn)
2785 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2786 	else
2787 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2788 
2789 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2790 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2791 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2792 	hdr->offset		= cpu_to_be32(datain->offset);
2793 
2794 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2795 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2796 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2797 		ntohl(hdr->offset), datain->length, conn->cid);
2798 }
2799 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2800 
2801 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2802 {
2803 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2804 	struct iscsi_datain datain;
2805 	struct iscsi_datain_req *dr;
2806 	int eodr = 0, ret;
2807 	bool set_statsn = false;
2808 
2809 	memset(&datain, 0, sizeof(struct iscsi_datain));
2810 	dr = iscsit_get_datain_values(cmd, &datain);
2811 	if (!dr) {
2812 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2813 				cmd->init_task_tag);
2814 		return -1;
2815 	}
2816 	/*
2817 	 * Be paranoid and double check the logic for now.
2818 	 */
2819 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2820 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2821 			" datain.length: %u exceeds cmd->data_length: %u\n",
2822 			cmd->init_task_tag, datain.offset, datain.length,
2823 			cmd->se_cmd.data_length);
2824 		return -1;
2825 	}
2826 
2827 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2828 	/*
2829 	 * Special case for successfully execution w/ both DATAIN
2830 	 * and Sense Data.
2831 	 */
2832 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2833 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2834 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2835 	else {
2836 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2837 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2838 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2839 			cmd->stat_sn = conn->stat_sn++;
2840 			set_statsn = true;
2841 		} else if (dr->dr_complete ==
2842 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2843 			set_statsn = true;
2844 	}
2845 
2846 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2847 
2848 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2849 	if (ret < 0)
2850 		return ret;
2851 
2852 	if (dr->dr_complete) {
2853 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2854 				2 : 1;
2855 		iscsit_free_datain_req(cmd, dr);
2856 	}
2857 
2858 	return eodr;
2859 }
2860 
2861 int
2862 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2863 			struct iscsi_logout_rsp *hdr)
2864 {
2865 	struct iscsi_conn *logout_conn = NULL;
2866 	struct iscsi_conn_recovery *cr = NULL;
2867 	struct iscsi_session *sess = conn->sess;
2868 	/*
2869 	 * The actual shutting down of Sessions and/or Connections
2870 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2871 	 * is done in scsi_logout_post_handler().
2872 	 */
2873 	switch (cmd->logout_reason) {
2874 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2875 		pr_debug("iSCSI session logout successful, setting"
2876 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2877 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2878 		break;
2879 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2880 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2881 			break;
2882 		/*
2883 		 * For CLOSECONNECTION logout requests carrying
2884 		 * a matching logout CID -> local CID, the reference
2885 		 * for the local CID will have been incremented in
2886 		 * iscsi_logout_closeconnection().
2887 		 *
2888 		 * For CLOSECONNECTION logout requests carrying
2889 		 * a different CID than the connection it arrived
2890 		 * on, the connection responding to cmd->logout_cid
2891 		 * is stopped in iscsit_logout_post_handler_diffcid().
2892 		 */
2893 
2894 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2895 			" successful.\n", cmd->logout_cid, conn->cid);
2896 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2897 		break;
2898 	case ISCSI_LOGOUT_REASON_RECOVERY:
2899 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2900 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2901 			break;
2902 		/*
2903 		 * If the connection is still active from our point of view
2904 		 * force connection recovery to occur.
2905 		 */
2906 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2907 				cmd->logout_cid);
2908 		if (logout_conn) {
2909 			iscsit_connection_reinstatement_rcfr(logout_conn);
2910 			iscsit_dec_conn_usage_count(logout_conn);
2911 		}
2912 
2913 		cr = iscsit_get_inactive_connection_recovery_entry(
2914 				conn->sess, cmd->logout_cid);
2915 		if (!cr) {
2916 			pr_err("Unable to locate CID: %hu for"
2917 			" REMOVECONNFORRECOVERY Logout Request.\n",
2918 				cmd->logout_cid);
2919 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2920 			break;
2921 		}
2922 
2923 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2924 
2925 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2926 			" for recovery for CID: %hu on CID: %hu successful.\n",
2927 				cmd->logout_cid, conn->cid);
2928 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2929 		break;
2930 	default:
2931 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2932 				cmd->logout_reason);
2933 		return -1;
2934 	}
2935 
2936 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2937 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2938 	hdr->response		= cmd->logout_response;
2939 	hdr->itt		= cmd->init_task_tag;
2940 	cmd->stat_sn		= conn->stat_sn++;
2941 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2942 
2943 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2944 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2945 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2946 
2947 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2948 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2949 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2950 		cmd->logout_cid, conn->cid);
2951 
2952 	return 0;
2953 }
2954 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2955 
2956 static int
2957 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2958 {
2959 	int rc;
2960 
2961 	rc = iscsit_build_logout_rsp(cmd, conn,
2962 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2963 	if (rc < 0)
2964 		return rc;
2965 
2966 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2967 }
2968 
2969 void
2970 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2971 		       struct iscsi_nopin *hdr, bool nopout_response)
2972 {
2973 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2974 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2975         hton24(hdr->dlength, cmd->buf_ptr_size);
2976 	if (nopout_response)
2977 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2978 	hdr->itt		= cmd->init_task_tag;
2979 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2980 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2981 				  conn->stat_sn;
2982 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2983 
2984 	if (nopout_response)
2985 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2986 
2987 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2988 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2989 
2990 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2991 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2992 		"Solicited" : "Unsolicited", cmd->init_task_tag,
2993 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2994 }
2995 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2996 
2997 /*
2998  *	Unsolicited NOPIN, either requesting a response or not.
2999  */
3000 static int iscsit_send_unsolicited_nopin(
3001 	struct iscsi_cmd *cmd,
3002 	struct iscsi_conn *conn,
3003 	int want_response)
3004 {
3005 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3006 	int ret;
3007 
3008 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3009 
3010 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3011 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3012 
3013 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3014 	if (ret < 0)
3015 		return ret;
3016 
3017 	spin_lock_bh(&cmd->istate_lock);
3018 	cmd->i_state = want_response ?
3019 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3020 	spin_unlock_bh(&cmd->istate_lock);
3021 
3022 	return 0;
3023 }
3024 
3025 static int
3026 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3027 {
3028 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3029 
3030 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3031 
3032 	/*
3033 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
3034 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
3035 	 */
3036 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3037 
3038 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3039 						     cmd->buf_ptr,
3040 						     cmd->buf_ptr_size);
3041 }
3042 
3043 static int iscsit_send_r2t(
3044 	struct iscsi_cmd *cmd,
3045 	struct iscsi_conn *conn)
3046 {
3047 	struct iscsi_r2t *r2t;
3048 	struct iscsi_r2t_rsp *hdr;
3049 	int ret;
3050 
3051 	r2t = iscsit_get_r2t_from_list(cmd);
3052 	if (!r2t)
3053 		return -1;
3054 
3055 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3056 	memset(hdr, 0, ISCSI_HDR_LEN);
3057 	hdr->opcode		= ISCSI_OP_R2T;
3058 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3059 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3060 			(struct scsi_lun *)&hdr->lun);
3061 	hdr->itt		= cmd->init_task_tag;
3062 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3063 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3064 	else
3065 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3066 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3067 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3068 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3069 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3070 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3071 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3072 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3073 
3074 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3075 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3076 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3077 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3078 			r2t->offset, r2t->xfer_len, conn->cid);
3079 
3080 	spin_lock_bh(&cmd->r2t_lock);
3081 	r2t->sent_r2t = 1;
3082 	spin_unlock_bh(&cmd->r2t_lock);
3083 
3084 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3085 	if (ret < 0) {
3086 		return ret;
3087 	}
3088 
3089 	spin_lock_bh(&cmd->dataout_timeout_lock);
3090 	iscsit_start_dataout_timer(cmd, conn);
3091 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3092 
3093 	return 0;
3094 }
3095 
3096 /*
3097  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3098  *		connection recovery.
3099  */
3100 int iscsit_build_r2ts_for_cmd(
3101 	struct iscsi_conn *conn,
3102 	struct iscsi_cmd *cmd,
3103 	bool recovery)
3104 {
3105 	int first_r2t = 1;
3106 	u32 offset = 0, xfer_len = 0;
3107 
3108 	spin_lock_bh(&cmd->r2t_lock);
3109 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3110 		spin_unlock_bh(&cmd->r2t_lock);
3111 		return 0;
3112 	}
3113 
3114 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3115 	    !recovery)
3116 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3117 
3118 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3119 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3120 			offset = cmd->r2t_offset;
3121 
3122 			if (first_r2t && recovery) {
3123 				int new_data_end = offset +
3124 					conn->sess->sess_ops->MaxBurstLength -
3125 					cmd->next_burst_len;
3126 
3127 				if (new_data_end > cmd->se_cmd.data_length)
3128 					xfer_len = cmd->se_cmd.data_length - offset;
3129 				else
3130 					xfer_len =
3131 						conn->sess->sess_ops->MaxBurstLength -
3132 						cmd->next_burst_len;
3133 			} else {
3134 				int new_data_end = offset +
3135 					conn->sess->sess_ops->MaxBurstLength;
3136 
3137 				if (new_data_end > cmd->se_cmd.data_length)
3138 					xfer_len = cmd->se_cmd.data_length - offset;
3139 				else
3140 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3141 			}
3142 			cmd->r2t_offset += xfer_len;
3143 
3144 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3145 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3146 		} else {
3147 			struct iscsi_seq *seq;
3148 
3149 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3150 			if (!seq) {
3151 				spin_unlock_bh(&cmd->r2t_lock);
3152 				return -1;
3153 			}
3154 
3155 			offset = seq->offset;
3156 			xfer_len = seq->xfer_len;
3157 
3158 			if (cmd->seq_send_order == cmd->seq_count)
3159 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3160 		}
3161 		cmd->outstanding_r2ts++;
3162 		first_r2t = 0;
3163 
3164 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3165 			spin_unlock_bh(&cmd->r2t_lock);
3166 			return -1;
3167 		}
3168 
3169 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3170 			break;
3171 	}
3172 	spin_unlock_bh(&cmd->r2t_lock);
3173 
3174 	return 0;
3175 }
3176 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3177 
3178 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3179 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3180 {
3181 	if (inc_stat_sn)
3182 		cmd->stat_sn = conn->stat_sn++;
3183 
3184 	atomic_long_inc(&conn->sess->rsp_pdus);
3185 
3186 	memset(hdr, 0, ISCSI_HDR_LEN);
3187 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3188 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3189 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3190 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3191 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3192 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3193 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3194 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3195 	}
3196 	hdr->response		= cmd->iscsi_response;
3197 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3198 	hdr->itt		= cmd->init_task_tag;
3199 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3200 
3201 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3202 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3203 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3204 
3205 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3206 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3207 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3208 		cmd->se_cmd.scsi_status, conn->cid);
3209 }
3210 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3211 
3212 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3213 {
3214 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3215 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3216 	void *data_buf = NULL;
3217 	u32 padding = 0, data_buf_len = 0;
3218 
3219 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3220 
3221 	/*
3222 	 * Attach SENSE DATA payload to iSCSI Response PDU
3223 	 */
3224 	if (cmd->se_cmd.sense_buffer &&
3225 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3226 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3227 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3228 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3229 
3230 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3231 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3232 		data_buf = cmd->sense_buffer;
3233 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3234 
3235 		if (padding) {
3236 			memset(cmd->sense_buffer +
3237 				cmd->se_cmd.scsi_sense_length, 0, padding);
3238 			pr_debug("Adding %u bytes of padding to"
3239 				" SENSE.\n", padding);
3240 		}
3241 
3242 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3243 				" Response PDU\n",
3244 				cmd->se_cmd.scsi_sense_length);
3245 	}
3246 
3247 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3248 						     data_buf_len);
3249 }
3250 
3251 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3252 {
3253 	switch (se_tmr->response) {
3254 	case TMR_FUNCTION_COMPLETE:
3255 		return ISCSI_TMF_RSP_COMPLETE;
3256 	case TMR_TASK_DOES_NOT_EXIST:
3257 		return ISCSI_TMF_RSP_NO_TASK;
3258 	case TMR_LUN_DOES_NOT_EXIST:
3259 		return ISCSI_TMF_RSP_NO_LUN;
3260 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3261 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3262 	case TMR_FUNCTION_REJECTED:
3263 	default:
3264 		return ISCSI_TMF_RSP_REJECTED;
3265 	}
3266 }
3267 
3268 void
3269 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3270 			  struct iscsi_tm_rsp *hdr)
3271 {
3272 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3273 
3274 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3275 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3276 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3277 	hdr->itt		= cmd->init_task_tag;
3278 	cmd->stat_sn		= conn->stat_sn++;
3279 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3280 
3281 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3282 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3283 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3284 
3285 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3286 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3287 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3288 }
3289 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3290 
3291 static int
3292 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3293 {
3294 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3295 
3296 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3297 
3298 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3299 }
3300 
3301 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3302 {
3303 	bool ret = false;
3304 
3305 	if (np->np_sockaddr.ss_family == AF_INET6) {
3306 		const struct sockaddr_in6 sin6 = {
3307 			.sin6_addr = IN6ADDR_ANY_INIT };
3308 		struct sockaddr_in6 *sock_in6 =
3309 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3310 
3311 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3312 				sin6.sin6_addr.s6_addr, 16))
3313 			ret = true;
3314 	} else {
3315 		struct sockaddr_in * sock_in =
3316 			(struct sockaddr_in *)&np->np_sockaddr;
3317 
3318 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3319 			ret = true;
3320 	}
3321 
3322 	return ret;
3323 }
3324 
3325 #define SENDTARGETS_BUF_LIMIT 32768U
3326 
3327 static int
3328 iscsit_build_sendtargets_response(struct iscsi_cmd *cmd,
3329 				  enum iscsit_transport_type network_transport,
3330 				  int skip_bytes, bool *completed)
3331 {
3332 	char *payload = NULL;
3333 	struct iscsi_conn *conn = cmd->conn;
3334 	struct iscsi_portal_group *tpg;
3335 	struct iscsi_tiqn *tiqn;
3336 	struct iscsi_tpg_np *tpg_np;
3337 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3338 	int target_name_printed;
3339 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3340 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3341 	bool active;
3342 
3343 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3344 			 SENDTARGETS_BUF_LIMIT);
3345 
3346 	payload = kzalloc(buffer_len, GFP_KERNEL);
3347 	if (!payload) {
3348 		pr_err("Unable to allocate memory for sendtargets"
3349 				" response.\n");
3350 		return -ENOMEM;
3351 	}
3352 	/*
3353 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3354 	 * explicit case..
3355 	 */
3356 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3357 		text_ptr = strchr(text_in, '=');
3358 		if (!text_ptr) {
3359 			pr_err("Unable to locate '=' string in text_in:"
3360 			       " %s\n", text_in);
3361 			kfree(payload);
3362 			return -EINVAL;
3363 		}
3364 		/*
3365 		 * Skip over '=' character..
3366 		 */
3367 		text_ptr += 1;
3368 	}
3369 
3370 	spin_lock(&tiqn_lock);
3371 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3372 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3373 		     strcmp(tiqn->tiqn, text_ptr)) {
3374 			continue;
3375 		}
3376 
3377 		target_name_printed = 0;
3378 
3379 		spin_lock(&tiqn->tiqn_tpg_lock);
3380 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3381 
3382 			/* If demo_mode_discovery=0 and generate_node_acls=0
3383 			 * (demo mode dislabed) do not return
3384 			 * TargetName+TargetAddress unless a NodeACL exists.
3385 			 */
3386 
3387 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3388 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3389 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3390 				cmd->conn->sess->sess_ops->InitiatorName))) {
3391 				continue;
3392 			}
3393 
3394 			spin_lock(&tpg->tpg_state_lock);
3395 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3396 			spin_unlock(&tpg->tpg_state_lock);
3397 
3398 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3399 				continue;
3400 
3401 			spin_lock(&tpg->tpg_np_lock);
3402 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3403 						tpg_np_list) {
3404 				struct iscsi_np *np = tpg_np->tpg_np;
3405 				bool inaddr_any = iscsit_check_inaddr_any(np);
3406 				struct sockaddr_storage *sockaddr;
3407 
3408 				if (np->np_network_transport != network_transport)
3409 					continue;
3410 
3411 				if (!target_name_printed) {
3412 					len = sprintf(buf, "TargetName=%s",
3413 						      tiqn->tiqn);
3414 					len += 1;
3415 
3416 					if ((len + payload_len) > buffer_len) {
3417 						spin_unlock(&tpg->tpg_np_lock);
3418 						spin_unlock(&tiqn->tiqn_tpg_lock);
3419 						end_of_buf = 1;
3420 						goto eob;
3421 					}
3422 
3423 					if (skip_bytes && len <= skip_bytes) {
3424 						skip_bytes -= len;
3425 					} else {
3426 						memcpy(payload + payload_len, buf, len);
3427 						payload_len += len;
3428 						target_name_printed = 1;
3429 						if (len > skip_bytes)
3430 							skip_bytes = 0;
3431 					}
3432 				}
3433 
3434 				if (inaddr_any)
3435 					sockaddr = &conn->local_sockaddr;
3436 				else
3437 					sockaddr = &np->np_sockaddr;
3438 
3439 				len = sprintf(buf, "TargetAddress="
3440 					      "%pISpc,%hu",
3441 					      sockaddr,
3442 					      tpg->tpgt);
3443 				len += 1;
3444 
3445 				if ((len + payload_len) > buffer_len) {
3446 					spin_unlock(&tpg->tpg_np_lock);
3447 					spin_unlock(&tiqn->tiqn_tpg_lock);
3448 					end_of_buf = 1;
3449 					goto eob;
3450 				}
3451 
3452 				if (skip_bytes && len <= skip_bytes) {
3453 					skip_bytes -= len;
3454 				} else {
3455 					memcpy(payload + payload_len, buf, len);
3456 					payload_len += len;
3457 					if (len > skip_bytes)
3458 						skip_bytes = 0;
3459 				}
3460 			}
3461 			spin_unlock(&tpg->tpg_np_lock);
3462 		}
3463 		spin_unlock(&tiqn->tiqn_tpg_lock);
3464 eob:
3465 		if (end_of_buf) {
3466 			*completed = false;
3467 			break;
3468 		}
3469 
3470 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3471 			break;
3472 	}
3473 	spin_unlock(&tiqn_lock);
3474 
3475 	cmd->buf_ptr = payload;
3476 
3477 	return payload_len;
3478 }
3479 
3480 int
3481 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3482 		      struct iscsi_text_rsp *hdr,
3483 		      enum iscsit_transport_type network_transport)
3484 {
3485 	int text_length, padding;
3486 	bool completed = true;
3487 
3488 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3489 							cmd->read_data_done,
3490 							&completed);
3491 	if (text_length < 0)
3492 		return text_length;
3493 
3494 	if (completed) {
3495 		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3496 	} else {
3497 		hdr->flags |= ISCSI_FLAG_TEXT_CONTINUE;
3498 		cmd->read_data_done += text_length;
3499 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3500 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3501 	}
3502 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3503 	padding = ((-text_length) & 3);
3504 	hton24(hdr->dlength, text_length);
3505 	hdr->itt = cmd->init_task_tag;
3506 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3507 	cmd->stat_sn = conn->stat_sn++;
3508 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3509 
3510 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3511 	/*
3512 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3513 	 * correctly increment MaxCmdSN for each response answering a
3514 	 * non immediate text request with a valid CmdSN.
3515 	 */
3516 	cmd->maxcmdsn_inc = 0;
3517 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3518 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3519 
3520 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3521 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3522 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3523 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3524 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3525 
3526 	return text_length + padding;
3527 }
3528 EXPORT_SYMBOL(iscsit_build_text_rsp);
3529 
3530 static int iscsit_send_text_rsp(
3531 	struct iscsi_cmd *cmd,
3532 	struct iscsi_conn *conn)
3533 {
3534 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3535 	int text_length;
3536 
3537 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3538 				conn->conn_transport->transport_type);
3539 	if (text_length < 0)
3540 		return text_length;
3541 
3542 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3543 						     cmd->buf_ptr,
3544 						     text_length);
3545 }
3546 
3547 void
3548 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3549 		    struct iscsi_reject *hdr)
3550 {
3551 	hdr->opcode		= ISCSI_OP_REJECT;
3552 	hdr->reason		= cmd->reject_reason;
3553 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3554 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3555 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3556 	cmd->stat_sn		= conn->stat_sn++;
3557 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3558 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3559 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3560 
3561 }
3562 EXPORT_SYMBOL(iscsit_build_reject);
3563 
3564 static int iscsit_send_reject(
3565 	struct iscsi_cmd *cmd,
3566 	struct iscsi_conn *conn)
3567 {
3568 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3569 
3570 	iscsit_build_reject(cmd, conn, hdr);
3571 
3572 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3573 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3574 
3575 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3576 						     cmd->buf_ptr,
3577 						     ISCSI_HDR_LEN);
3578 }
3579 
3580 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3581 {
3582 	int ord, cpu;
3583 	/*
3584 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3585 	 * within iscsit_start_kthreads()
3586 	 *
3587 	 * Here we use bitmap_id to determine which CPU that this
3588 	 * iSCSI connection's RX/TX threads will be scheduled to
3589 	 * execute upon.
3590 	 */
3591 	ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3592 	for_each_online_cpu(cpu) {
3593 		if (ord-- == 0) {
3594 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3595 			return;
3596 		}
3597 	}
3598 	/*
3599 	 * This should never be reached..
3600 	 */
3601 	dump_stack();
3602 	cpumask_setall(conn->conn_cpumask);
3603 }
3604 
3605 int
3606 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3607 {
3608 	int ret;
3609 
3610 	switch (state) {
3611 	case ISTATE_SEND_R2T:
3612 		ret = iscsit_send_r2t(cmd, conn);
3613 		if (ret < 0)
3614 			goto err;
3615 		break;
3616 	case ISTATE_REMOVE:
3617 		spin_lock_bh(&conn->cmd_lock);
3618 		list_del_init(&cmd->i_conn_node);
3619 		spin_unlock_bh(&conn->cmd_lock);
3620 
3621 		iscsit_free_cmd(cmd, false);
3622 		break;
3623 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3624 		iscsit_mod_nopin_response_timer(conn);
3625 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3626 		if (ret < 0)
3627 			goto err;
3628 		break;
3629 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3630 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3631 		if (ret < 0)
3632 			goto err;
3633 		break;
3634 	default:
3635 		pr_err("Unknown Opcode: 0x%02x ITT:"
3636 		       " 0x%08x, i_state: %d on CID: %hu\n",
3637 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3638 		       conn->cid);
3639 		goto err;
3640 	}
3641 
3642 	return 0;
3643 
3644 err:
3645 	return -1;
3646 }
3647 EXPORT_SYMBOL(iscsit_immediate_queue);
3648 
3649 static int
3650 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3651 {
3652 	struct iscsit_transport *t = conn->conn_transport;
3653 	struct iscsi_queue_req *qr;
3654 	struct iscsi_cmd *cmd;
3655 	u8 state;
3656 	int ret;
3657 
3658 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3659 		atomic_set(&conn->check_immediate_queue, 0);
3660 		cmd = qr->cmd;
3661 		state = qr->state;
3662 		kmem_cache_free(lio_qr_cache, qr);
3663 
3664 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3665 		if (ret < 0)
3666 			return ret;
3667 	}
3668 
3669 	return 0;
3670 }
3671 
3672 int
3673 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3674 {
3675 	int ret;
3676 
3677 check_rsp_state:
3678 	switch (state) {
3679 	case ISTATE_SEND_DATAIN:
3680 		ret = iscsit_send_datain(cmd, conn);
3681 		if (ret < 0)
3682 			goto err;
3683 		else if (!ret)
3684 			/* more drs */
3685 			goto check_rsp_state;
3686 		else if (ret == 1) {
3687 			/* all done */
3688 			spin_lock_bh(&cmd->istate_lock);
3689 			cmd->i_state = ISTATE_SENT_STATUS;
3690 			spin_unlock_bh(&cmd->istate_lock);
3691 
3692 			if (atomic_read(&conn->check_immediate_queue))
3693 				return 1;
3694 
3695 			return 0;
3696 		} else if (ret == 2) {
3697 			/* Still must send status,
3698 			   SCF_TRANSPORT_TASK_SENSE was set */
3699 			spin_lock_bh(&cmd->istate_lock);
3700 			cmd->i_state = ISTATE_SEND_STATUS;
3701 			spin_unlock_bh(&cmd->istate_lock);
3702 			state = ISTATE_SEND_STATUS;
3703 			goto check_rsp_state;
3704 		}
3705 
3706 		break;
3707 	case ISTATE_SEND_STATUS:
3708 	case ISTATE_SEND_STATUS_RECOVERY:
3709 		ret = iscsit_send_response(cmd, conn);
3710 		break;
3711 	case ISTATE_SEND_LOGOUTRSP:
3712 		ret = iscsit_send_logout(cmd, conn);
3713 		break;
3714 	case ISTATE_SEND_ASYNCMSG:
3715 		ret = iscsit_send_conn_drop_async_message(
3716 			cmd, conn);
3717 		break;
3718 	case ISTATE_SEND_NOPIN:
3719 		ret = iscsit_send_nopin(cmd, conn);
3720 		break;
3721 	case ISTATE_SEND_REJECT:
3722 		ret = iscsit_send_reject(cmd, conn);
3723 		break;
3724 	case ISTATE_SEND_TASKMGTRSP:
3725 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3726 		if (ret != 0)
3727 			break;
3728 		ret = iscsit_tmr_post_handler(cmd, conn);
3729 		if (ret != 0)
3730 			iscsit_fall_back_to_erl0(conn->sess);
3731 		break;
3732 	case ISTATE_SEND_TEXTRSP:
3733 		ret = iscsit_send_text_rsp(cmd, conn);
3734 		break;
3735 	default:
3736 		pr_err("Unknown Opcode: 0x%02x ITT:"
3737 		       " 0x%08x, i_state: %d on CID: %hu\n",
3738 		       cmd->iscsi_opcode, cmd->init_task_tag,
3739 		       state, conn->cid);
3740 		goto err;
3741 	}
3742 	if (ret < 0)
3743 		goto err;
3744 
3745 	switch (state) {
3746 	case ISTATE_SEND_LOGOUTRSP:
3747 		if (!iscsit_logout_post_handler(cmd, conn))
3748 			return -ECONNRESET;
3749 		/* fall through */
3750 	case ISTATE_SEND_STATUS:
3751 	case ISTATE_SEND_ASYNCMSG:
3752 	case ISTATE_SEND_NOPIN:
3753 	case ISTATE_SEND_STATUS_RECOVERY:
3754 	case ISTATE_SEND_TEXTRSP:
3755 	case ISTATE_SEND_TASKMGTRSP:
3756 	case ISTATE_SEND_REJECT:
3757 		spin_lock_bh(&cmd->istate_lock);
3758 		cmd->i_state = ISTATE_SENT_STATUS;
3759 		spin_unlock_bh(&cmd->istate_lock);
3760 		break;
3761 	default:
3762 		pr_err("Unknown Opcode: 0x%02x ITT:"
3763 		       " 0x%08x, i_state: %d on CID: %hu\n",
3764 		       cmd->iscsi_opcode, cmd->init_task_tag,
3765 		       cmd->i_state, conn->cid);
3766 		goto err;
3767 	}
3768 
3769 	if (atomic_read(&conn->check_immediate_queue))
3770 		return 1;
3771 
3772 	return 0;
3773 
3774 err:
3775 	return -1;
3776 }
3777 EXPORT_SYMBOL(iscsit_response_queue);
3778 
3779 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3780 {
3781 	struct iscsit_transport *t = conn->conn_transport;
3782 	struct iscsi_queue_req *qr;
3783 	struct iscsi_cmd *cmd;
3784 	u8 state;
3785 	int ret;
3786 
3787 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3788 		cmd = qr->cmd;
3789 		state = qr->state;
3790 		kmem_cache_free(lio_qr_cache, qr);
3791 
3792 		ret = t->iscsit_response_queue(conn, cmd, state);
3793 		if (ret == 1 || ret < 0)
3794 			return ret;
3795 	}
3796 
3797 	return 0;
3798 }
3799 
3800 int iscsi_target_tx_thread(void *arg)
3801 {
3802 	int ret = 0;
3803 	struct iscsi_conn *conn = arg;
3804 	/*
3805 	 * Allow ourselves to be interrupted by SIGINT so that a
3806 	 * connection recovery / failure event can be triggered externally.
3807 	 */
3808 	allow_signal(SIGINT);
3809 
3810 	while (!kthread_should_stop()) {
3811 		/*
3812 		 * Ensure that both TX and RX per connection kthreads
3813 		 * are scheduled to run on the same CPU.
3814 		 */
3815 		iscsit_thread_check_cpumask(conn, current, 1);
3816 
3817 		wait_event_interruptible(conn->queues_wq,
3818 					 !iscsit_conn_all_queues_empty(conn));
3819 
3820 		if (signal_pending(current))
3821 			goto transport_err;
3822 
3823 get_immediate:
3824 		ret = iscsit_handle_immediate_queue(conn);
3825 		if (ret < 0)
3826 			goto transport_err;
3827 
3828 		ret = iscsit_handle_response_queue(conn);
3829 		if (ret == 1)
3830 			goto get_immediate;
3831 		else if (ret == -ECONNRESET)
3832 			goto out;
3833 		else if (ret < 0)
3834 			goto transport_err;
3835 	}
3836 
3837 transport_err:
3838 	/*
3839 	 * Avoid the normal connection failure code-path if this connection
3840 	 * is still within LOGIN mode, and iscsi_np process context is
3841 	 * responsible for cleaning up the early connection failure.
3842 	 */
3843 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3844 		iscsit_take_action_for_connection_exit(conn);
3845 out:
3846 	return 0;
3847 }
3848 
3849 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3850 {
3851 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3852 	struct iscsi_cmd *cmd;
3853 	int ret = 0;
3854 
3855 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3856 	case ISCSI_OP_SCSI_CMD:
3857 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3858 		if (!cmd)
3859 			goto reject;
3860 
3861 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3862 		break;
3863 	case ISCSI_OP_SCSI_DATA_OUT:
3864 		ret = iscsit_handle_data_out(conn, buf);
3865 		break;
3866 	case ISCSI_OP_NOOP_OUT:
3867 		cmd = NULL;
3868 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3869 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3870 			if (!cmd)
3871 				goto reject;
3872 		}
3873 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3874 		break;
3875 	case ISCSI_OP_SCSI_TMFUNC:
3876 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3877 		if (!cmd)
3878 			goto reject;
3879 
3880 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3881 		break;
3882 	case ISCSI_OP_TEXT:
3883 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3884 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3885 			if (!cmd)
3886 				goto reject;
3887 		} else {
3888 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3889 			if (!cmd)
3890 				goto reject;
3891 		}
3892 
3893 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3894 		break;
3895 	case ISCSI_OP_LOGOUT:
3896 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3897 		if (!cmd)
3898 			goto reject;
3899 
3900 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3901 		if (ret > 0)
3902 			wait_for_completion_timeout(&conn->conn_logout_comp,
3903 					SECONDS_FOR_LOGOUT_COMP * HZ);
3904 		break;
3905 	case ISCSI_OP_SNACK:
3906 		ret = iscsit_handle_snack(conn, buf);
3907 		break;
3908 	default:
3909 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3910 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3911 			pr_err("Cannot recover from unknown"
3912 			" opcode while ERL=0, closing iSCSI connection.\n");
3913 			return -1;
3914 		}
3915 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
3916 		       " closing iSCSI connection.\n");
3917 		ret = -1;
3918 		break;
3919 	}
3920 
3921 	return ret;
3922 reject:
3923 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
3924 }
3925 
3926 static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
3927 {
3928 	bool ret;
3929 
3930 	spin_lock_bh(&conn->state_lock);
3931 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
3932 	spin_unlock_bh(&conn->state_lock);
3933 
3934 	return ret;
3935 }
3936 
3937 static void iscsit_get_rx_pdu(struct iscsi_conn *conn)
3938 {
3939 	int ret;
3940 	u8 buffer[ISCSI_HDR_LEN], opcode;
3941 	u32 checksum = 0, digest = 0;
3942 	struct kvec iov;
3943 
3944 	while (!kthread_should_stop()) {
3945 		/*
3946 		 * Ensure that both TX and RX per connection kthreads
3947 		 * are scheduled to run on the same CPU.
3948 		 */
3949 		iscsit_thread_check_cpumask(conn, current, 0);
3950 
3951 		memset(buffer, 0, ISCSI_HDR_LEN);
3952 		memset(&iov, 0, sizeof(struct kvec));
3953 
3954 		iov.iov_base	= buffer;
3955 		iov.iov_len	= ISCSI_HDR_LEN;
3956 
3957 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
3958 		if (ret != ISCSI_HDR_LEN) {
3959 			iscsit_rx_thread_wait_for_tcp(conn);
3960 			return;
3961 		}
3962 
3963 		if (conn->conn_ops->HeaderDigest) {
3964 			iov.iov_base	= &digest;
3965 			iov.iov_len	= ISCSI_CRC_LEN;
3966 
3967 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
3968 			if (ret != ISCSI_CRC_LEN) {
3969 				iscsit_rx_thread_wait_for_tcp(conn);
3970 				return;
3971 			}
3972 
3973 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
3974 					buffer, ISCSI_HDR_LEN,
3975 					0, NULL, (u8 *)&checksum);
3976 
3977 			if (digest != checksum) {
3978 				pr_err("HeaderDigest CRC32C failed,"
3979 					" received 0x%08x, computed 0x%08x\n",
3980 					digest, checksum);
3981 				/*
3982 				 * Set the PDU to 0xff so it will intentionally
3983 				 * hit default in the switch below.
3984 				 */
3985 				memset(buffer, 0xff, ISCSI_HDR_LEN);
3986 				atomic_long_inc(&conn->sess->conn_digest_errors);
3987 			} else {
3988 				pr_debug("Got HeaderDigest CRC32C"
3989 						" 0x%08x\n", checksum);
3990 			}
3991 		}
3992 
3993 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
3994 			return;
3995 
3996 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
3997 
3998 		if (conn->sess->sess_ops->SessionType &&
3999 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4000 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4001 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4002 			" while in Discovery Session, rejecting.\n", opcode);
4003 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4004 					  buffer);
4005 			return;
4006 		}
4007 
4008 		ret = iscsi_target_rx_opcode(conn, buffer);
4009 		if (ret < 0)
4010 			return;
4011 	}
4012 }
4013 
4014 int iscsi_target_rx_thread(void *arg)
4015 {
4016 	int rc;
4017 	struct iscsi_conn *conn = arg;
4018 
4019 	/*
4020 	 * Allow ourselves to be interrupted by SIGINT so that a
4021 	 * connection recovery / failure event can be triggered externally.
4022 	 */
4023 	allow_signal(SIGINT);
4024 	/*
4025 	 * Wait for iscsi_post_login_handler() to complete before allowing
4026 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4027 	 */
4028 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4029 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4030 		return 0;
4031 
4032 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4033 		return 0;
4034 
4035 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4036 
4037 	if (!signal_pending(current))
4038 		atomic_set(&conn->transport_failed, 1);
4039 	iscsit_take_action_for_connection_exit(conn);
4040 	return 0;
4041 }
4042 
4043 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4044 {
4045 	LIST_HEAD(tmp_list);
4046 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4047 	struct iscsi_session *sess = conn->sess;
4048 	/*
4049 	 * We expect this function to only ever be called from either RX or TX
4050 	 * thread context via iscsit_close_connection() once the other context
4051 	 * has been reset -> returned sleeping pre-handler state.
4052 	 */
4053 	spin_lock_bh(&conn->cmd_lock);
4054 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4055 
4056 	list_for_each_entry(cmd, &tmp_list, i_conn_node) {
4057 		struct se_cmd *se_cmd = &cmd->se_cmd;
4058 
4059 		if (se_cmd->se_tfo != NULL) {
4060 			spin_lock(&se_cmd->t_state_lock);
4061 			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4062 			spin_unlock(&se_cmd->t_state_lock);
4063 		}
4064 	}
4065 	spin_unlock_bh(&conn->cmd_lock);
4066 
4067 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4068 		list_del_init(&cmd->i_conn_node);
4069 
4070 		iscsit_increment_maxcmdsn(cmd, sess);
4071 		iscsit_free_cmd(cmd, true);
4072 
4073 	}
4074 }
4075 
4076 static void iscsit_stop_timers_for_cmds(
4077 	struct iscsi_conn *conn)
4078 {
4079 	struct iscsi_cmd *cmd;
4080 
4081 	spin_lock_bh(&conn->cmd_lock);
4082 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4083 		if (cmd->data_direction == DMA_TO_DEVICE)
4084 			iscsit_stop_dataout_timer(cmd);
4085 	}
4086 	spin_unlock_bh(&conn->cmd_lock);
4087 }
4088 
4089 int iscsit_close_connection(
4090 	struct iscsi_conn *conn)
4091 {
4092 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4093 	struct iscsi_session	*sess = conn->sess;
4094 
4095 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4096 		" %u\n", conn->cid, sess->sid);
4097 	/*
4098 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4099 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4100 	 * sleeping and the logout response never got sent because the
4101 	 * connection failed.
4102 	 *
4103 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4104 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4105 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4106 	 * and to avoid iscsi_conn pointer dereference in iser-target code.
4107 	 */
4108 	if (!conn->conn_transport->rdma_shutdown)
4109 		complete(&conn->conn_logout_comp);
4110 
4111 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4112 		if (conn->tx_thread &&
4113 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4114 			send_sig(SIGINT, conn->tx_thread, 1);
4115 			kthread_stop(conn->tx_thread);
4116 		}
4117 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4118 		if (conn->rx_thread &&
4119 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4120 			send_sig(SIGINT, conn->rx_thread, 1);
4121 			kthread_stop(conn->rx_thread);
4122 		}
4123 	}
4124 
4125 	spin_lock(&iscsit_global->ts_bitmap_lock);
4126 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4127 			      get_order(1));
4128 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4129 
4130 	iscsit_stop_timers_for_cmds(conn);
4131 	iscsit_stop_nopin_response_timer(conn);
4132 	iscsit_stop_nopin_timer(conn);
4133 
4134 	if (conn->conn_transport->iscsit_wait_conn)
4135 		conn->conn_transport->iscsit_wait_conn(conn);
4136 
4137 	/*
4138 	 * During Connection recovery drop unacknowledged out of order
4139 	 * commands for this connection, and prepare the other commands
4140 	 * for realligence.
4141 	 *
4142 	 * During normal operation clear the out of order commands (but
4143 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4144 	 * struct iscsi_cmds.
4145 	 */
4146 	if (atomic_read(&conn->connection_recovery)) {
4147 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4148 		iscsit_prepare_cmds_for_realligance(conn);
4149 	} else {
4150 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4151 		iscsit_release_commands_from_conn(conn);
4152 	}
4153 	iscsit_free_queue_reqs_for_conn(conn);
4154 
4155 	/*
4156 	 * Handle decrementing session or connection usage count if
4157 	 * a logout response was not able to be sent because the
4158 	 * connection failed.  Fall back to Session Recovery here.
4159 	 */
4160 	if (atomic_read(&conn->conn_logout_remove)) {
4161 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4162 			iscsit_dec_conn_usage_count(conn);
4163 			iscsit_dec_session_usage_count(sess);
4164 		}
4165 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4166 			iscsit_dec_conn_usage_count(conn);
4167 
4168 		atomic_set(&conn->conn_logout_remove, 0);
4169 		atomic_set(&sess->session_reinstatement, 0);
4170 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4171 	}
4172 
4173 	spin_lock_bh(&sess->conn_lock);
4174 	list_del(&conn->conn_list);
4175 
4176 	/*
4177 	 * Attempt to let the Initiator know this connection failed by
4178 	 * sending an Connection Dropped Async Message on another
4179 	 * active connection.
4180 	 */
4181 	if (atomic_read(&conn->connection_recovery))
4182 		iscsit_build_conn_drop_async_message(conn);
4183 
4184 	spin_unlock_bh(&sess->conn_lock);
4185 
4186 	/*
4187 	 * If connection reinstatement is being performed on this connection,
4188 	 * up the connection reinstatement semaphore that is being blocked on
4189 	 * in iscsit_cause_connection_reinstatement().
4190 	 */
4191 	spin_lock_bh(&conn->state_lock);
4192 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4193 		spin_unlock_bh(&conn->state_lock);
4194 		complete(&conn->conn_wait_comp);
4195 		wait_for_completion(&conn->conn_post_wait_comp);
4196 		spin_lock_bh(&conn->state_lock);
4197 	}
4198 
4199 	/*
4200 	 * If connection reinstatement is being performed on this connection
4201 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4202 	 * connection wait rcfr semaphore that is being blocked on
4203 	 * an iscsit_connection_reinstatement_rcfr().
4204 	 */
4205 	if (atomic_read(&conn->connection_wait_rcfr)) {
4206 		spin_unlock_bh(&conn->state_lock);
4207 		complete(&conn->conn_wait_rcfr_comp);
4208 		wait_for_completion(&conn->conn_post_wait_comp);
4209 		spin_lock_bh(&conn->state_lock);
4210 	}
4211 	atomic_set(&conn->connection_reinstatement, 1);
4212 	spin_unlock_bh(&conn->state_lock);
4213 
4214 	/*
4215 	 * If any other processes are accessing this connection pointer we
4216 	 * must wait until they have completed.
4217 	 */
4218 	iscsit_check_conn_usage_count(conn);
4219 
4220 	ahash_request_free(conn->conn_tx_hash);
4221 	if (conn->conn_rx_hash) {
4222 		struct crypto_ahash *tfm;
4223 
4224 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4225 		ahash_request_free(conn->conn_rx_hash);
4226 		crypto_free_ahash(tfm);
4227 	}
4228 
4229 	free_cpumask_var(conn->conn_cpumask);
4230 
4231 	kfree(conn->conn_ops);
4232 	conn->conn_ops = NULL;
4233 
4234 	if (conn->sock)
4235 		sock_release(conn->sock);
4236 
4237 	if (conn->conn_transport->iscsit_free_conn)
4238 		conn->conn_transport->iscsit_free_conn(conn);
4239 
4240 	iscsit_put_transport(conn->conn_transport);
4241 
4242 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4243 	conn->conn_state = TARG_CONN_STATE_FREE;
4244 	kfree(conn);
4245 
4246 	spin_lock_bh(&sess->conn_lock);
4247 	atomic_dec(&sess->nconn);
4248 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4249 		" %s\n", atomic_read(&sess->nconn),
4250 		sess->sess_ops->InitiatorName);
4251 	/*
4252 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4253 	 * Session that they all fail.
4254 	 */
4255 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4256 	     !atomic_read(&sess->session_logout))
4257 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4258 
4259 	/*
4260 	 * If this was not the last connection in the session, and we are
4261 	 * performing session reinstatement or falling back to ERL=0, call
4262 	 * iscsit_stop_session() without sleeping to shutdown the other
4263 	 * active connections.
4264 	 */
4265 	if (atomic_read(&sess->nconn)) {
4266 		if (!atomic_read(&sess->session_reinstatement) &&
4267 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4268 			spin_unlock_bh(&sess->conn_lock);
4269 			return 0;
4270 		}
4271 		if (!atomic_read(&sess->session_stop_active)) {
4272 			atomic_set(&sess->session_stop_active, 1);
4273 			spin_unlock_bh(&sess->conn_lock);
4274 			iscsit_stop_session(sess, 0, 0);
4275 			return 0;
4276 		}
4277 		spin_unlock_bh(&sess->conn_lock);
4278 		return 0;
4279 	}
4280 
4281 	/*
4282 	 * If this was the last connection in the session and one of the
4283 	 * following is occurring:
4284 	 *
4285 	 * Session Reinstatement is not being performed, and are falling back
4286 	 * to ERL=0 call iscsit_close_session().
4287 	 *
4288 	 * Session Logout was requested.  iscsit_close_session() will be called
4289 	 * elsewhere.
4290 	 *
4291 	 * Session Continuation is not being performed, start the Time2Retain
4292 	 * handler and check if sleep_on_sess_wait_sem is active.
4293 	 */
4294 	if (!atomic_read(&sess->session_reinstatement) &&
4295 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4296 		spin_unlock_bh(&sess->conn_lock);
4297 		iscsit_close_session(sess);
4298 
4299 		return 0;
4300 	} else if (atomic_read(&sess->session_logout)) {
4301 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4302 		sess->session_state = TARG_SESS_STATE_FREE;
4303 		spin_unlock_bh(&sess->conn_lock);
4304 
4305 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4306 			complete(&sess->session_wait_comp);
4307 
4308 		return 0;
4309 	} else {
4310 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4311 		sess->session_state = TARG_SESS_STATE_FAILED;
4312 
4313 		if (!atomic_read(&sess->session_continuation)) {
4314 			spin_unlock_bh(&sess->conn_lock);
4315 			iscsit_start_time2retain_handler(sess);
4316 		} else
4317 			spin_unlock_bh(&sess->conn_lock);
4318 
4319 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4320 			complete(&sess->session_wait_comp);
4321 
4322 		return 0;
4323 	}
4324 }
4325 
4326 /*
4327  * If the iSCSI Session for the iSCSI Initiator Node exists,
4328  * forcefully shutdown the iSCSI NEXUS.
4329  */
4330 int iscsit_close_session(struct iscsi_session *sess)
4331 {
4332 	struct iscsi_portal_group *tpg = sess->tpg;
4333 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4334 
4335 	if (atomic_read(&sess->nconn)) {
4336 		pr_err("%d connection(s) still exist for iSCSI session"
4337 			" to %s\n", atomic_read(&sess->nconn),
4338 			sess->sess_ops->InitiatorName);
4339 		BUG();
4340 	}
4341 
4342 	spin_lock_bh(&se_tpg->session_lock);
4343 	atomic_set(&sess->session_logout, 1);
4344 	atomic_set(&sess->session_reinstatement, 1);
4345 	iscsit_stop_time2retain_timer(sess);
4346 	spin_unlock_bh(&se_tpg->session_lock);
4347 
4348 	/*
4349 	 * transport_deregister_session_configfs() will clear the
4350 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4351 	 * can be setting it again with __transport_register_session() in
4352 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4353 	 * completes in iscsi_np context.
4354 	 */
4355 	transport_deregister_session_configfs(sess->se_sess);
4356 
4357 	/*
4358 	 * If any other processes are accessing this session pointer we must
4359 	 * wait until they have completed.  If we are in an interrupt (the
4360 	 * time2retain handler) and contain and active session usage count we
4361 	 * restart the timer and exit.
4362 	 */
4363 	if (!in_interrupt()) {
4364 		if (iscsit_check_session_usage_count(sess) == 1)
4365 			iscsit_stop_session(sess, 1, 1);
4366 	} else {
4367 		if (iscsit_check_session_usage_count(sess) == 2) {
4368 			atomic_set(&sess->session_logout, 0);
4369 			iscsit_start_time2retain_handler(sess);
4370 			return 0;
4371 		}
4372 	}
4373 
4374 	transport_deregister_session(sess->se_sess);
4375 
4376 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4377 		iscsit_free_connection_recovery_entires(sess);
4378 
4379 	iscsit_free_all_ooo_cmdsns(sess);
4380 
4381 	spin_lock_bh(&se_tpg->session_lock);
4382 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4383 	sess->session_state = TARG_SESS_STATE_FREE;
4384 	pr_debug("Released iSCSI session from node: %s\n",
4385 			sess->sess_ops->InitiatorName);
4386 	tpg->nsessions--;
4387 	if (tpg->tpg_tiqn)
4388 		tpg->tpg_tiqn->tiqn_nsessions--;
4389 
4390 	pr_debug("Decremented number of active iSCSI Sessions on"
4391 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4392 
4393 	spin_lock(&sess_idr_lock);
4394 	idr_remove(&sess_idr, sess->session_index);
4395 	spin_unlock(&sess_idr_lock);
4396 
4397 	kfree(sess->sess_ops);
4398 	sess->sess_ops = NULL;
4399 	spin_unlock_bh(&se_tpg->session_lock);
4400 
4401 	kfree(sess);
4402 	return 0;
4403 }
4404 
4405 static void iscsit_logout_post_handler_closesession(
4406 	struct iscsi_conn *conn)
4407 {
4408 	struct iscsi_session *sess = conn->sess;
4409 	int sleep = 1;
4410 	/*
4411 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4412 	 * context during session logout, so clear tx_thread_active and
4413 	 * sleep if iscsit_close_connection() has not already occured.
4414 	 *
4415 	 * Since iser-target invokes this logic from it's own workqueue,
4416 	 * always sleep waiting for RX/TX thread shutdown to complete
4417 	 * within iscsit_close_connection().
4418 	 */
4419 	if (!conn->conn_transport->rdma_shutdown)
4420 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4421 
4422 	atomic_set(&conn->conn_logout_remove, 0);
4423 	complete(&conn->conn_logout_comp);
4424 
4425 	iscsit_dec_conn_usage_count(conn);
4426 	iscsit_stop_session(sess, sleep, sleep);
4427 	iscsit_dec_session_usage_count(sess);
4428 	iscsit_close_session(sess);
4429 }
4430 
4431 static void iscsit_logout_post_handler_samecid(
4432 	struct iscsi_conn *conn)
4433 {
4434 	int sleep = 1;
4435 
4436 	if (!conn->conn_transport->rdma_shutdown)
4437 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4438 
4439 	atomic_set(&conn->conn_logout_remove, 0);
4440 	complete(&conn->conn_logout_comp);
4441 
4442 	iscsit_cause_connection_reinstatement(conn, sleep);
4443 	iscsit_dec_conn_usage_count(conn);
4444 }
4445 
4446 static void iscsit_logout_post_handler_diffcid(
4447 	struct iscsi_conn *conn,
4448 	u16 cid)
4449 {
4450 	struct iscsi_conn *l_conn;
4451 	struct iscsi_session *sess = conn->sess;
4452 	bool conn_found = false;
4453 
4454 	if (!sess)
4455 		return;
4456 
4457 	spin_lock_bh(&sess->conn_lock);
4458 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4459 		if (l_conn->cid == cid) {
4460 			iscsit_inc_conn_usage_count(l_conn);
4461 			conn_found = true;
4462 			break;
4463 		}
4464 	}
4465 	spin_unlock_bh(&sess->conn_lock);
4466 
4467 	if (!conn_found)
4468 		return;
4469 
4470 	if (l_conn->sock)
4471 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4472 
4473 	spin_lock_bh(&l_conn->state_lock);
4474 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4475 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4476 	spin_unlock_bh(&l_conn->state_lock);
4477 
4478 	iscsit_cause_connection_reinstatement(l_conn, 1);
4479 	iscsit_dec_conn_usage_count(l_conn);
4480 }
4481 
4482 /*
4483  *	Return of 0 causes the TX thread to restart.
4484  */
4485 int iscsit_logout_post_handler(
4486 	struct iscsi_cmd *cmd,
4487 	struct iscsi_conn *conn)
4488 {
4489 	int ret = 0;
4490 
4491 	switch (cmd->logout_reason) {
4492 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4493 		switch (cmd->logout_response) {
4494 		case ISCSI_LOGOUT_SUCCESS:
4495 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4496 		default:
4497 			iscsit_logout_post_handler_closesession(conn);
4498 			break;
4499 		}
4500 		ret = 0;
4501 		break;
4502 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4503 		if (conn->cid == cmd->logout_cid) {
4504 			switch (cmd->logout_response) {
4505 			case ISCSI_LOGOUT_SUCCESS:
4506 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4507 			default:
4508 				iscsit_logout_post_handler_samecid(conn);
4509 				break;
4510 			}
4511 			ret = 0;
4512 		} else {
4513 			switch (cmd->logout_response) {
4514 			case ISCSI_LOGOUT_SUCCESS:
4515 				iscsit_logout_post_handler_diffcid(conn,
4516 					cmd->logout_cid);
4517 				break;
4518 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4519 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4520 			default:
4521 				break;
4522 			}
4523 			ret = 1;
4524 		}
4525 		break;
4526 	case ISCSI_LOGOUT_REASON_RECOVERY:
4527 		switch (cmd->logout_response) {
4528 		case ISCSI_LOGOUT_SUCCESS:
4529 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4530 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4531 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4532 		default:
4533 			break;
4534 		}
4535 		ret = 1;
4536 		break;
4537 	default:
4538 		break;
4539 
4540 	}
4541 	return ret;
4542 }
4543 EXPORT_SYMBOL(iscsit_logout_post_handler);
4544 
4545 void iscsit_fail_session(struct iscsi_session *sess)
4546 {
4547 	struct iscsi_conn *conn;
4548 
4549 	spin_lock_bh(&sess->conn_lock);
4550 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4551 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4552 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4553 	}
4554 	spin_unlock_bh(&sess->conn_lock);
4555 
4556 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4557 	sess->session_state = TARG_SESS_STATE_FAILED;
4558 }
4559 
4560 int iscsit_free_session(struct iscsi_session *sess)
4561 {
4562 	u16 conn_count = atomic_read(&sess->nconn);
4563 	struct iscsi_conn *conn, *conn_tmp = NULL;
4564 	int is_last;
4565 
4566 	spin_lock_bh(&sess->conn_lock);
4567 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4568 
4569 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4570 			conn_list) {
4571 		if (conn_count == 0)
4572 			break;
4573 
4574 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4575 			is_last = 1;
4576 		} else {
4577 			iscsit_inc_conn_usage_count(conn_tmp);
4578 			is_last = 0;
4579 		}
4580 		iscsit_inc_conn_usage_count(conn);
4581 
4582 		spin_unlock_bh(&sess->conn_lock);
4583 		iscsit_cause_connection_reinstatement(conn, 1);
4584 		spin_lock_bh(&sess->conn_lock);
4585 
4586 		iscsit_dec_conn_usage_count(conn);
4587 		if (is_last == 0)
4588 			iscsit_dec_conn_usage_count(conn_tmp);
4589 
4590 		conn_count--;
4591 	}
4592 
4593 	if (atomic_read(&sess->nconn)) {
4594 		spin_unlock_bh(&sess->conn_lock);
4595 		wait_for_completion(&sess->session_wait_comp);
4596 	} else
4597 		spin_unlock_bh(&sess->conn_lock);
4598 
4599 	iscsit_close_session(sess);
4600 	return 0;
4601 }
4602 
4603 void iscsit_stop_session(
4604 	struct iscsi_session *sess,
4605 	int session_sleep,
4606 	int connection_sleep)
4607 {
4608 	u16 conn_count = atomic_read(&sess->nconn);
4609 	struct iscsi_conn *conn, *conn_tmp = NULL;
4610 	int is_last;
4611 
4612 	spin_lock_bh(&sess->conn_lock);
4613 	if (session_sleep)
4614 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4615 
4616 	if (connection_sleep) {
4617 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4618 				conn_list) {
4619 			if (conn_count == 0)
4620 				break;
4621 
4622 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4623 				is_last = 1;
4624 			} else {
4625 				iscsit_inc_conn_usage_count(conn_tmp);
4626 				is_last = 0;
4627 			}
4628 			iscsit_inc_conn_usage_count(conn);
4629 
4630 			spin_unlock_bh(&sess->conn_lock);
4631 			iscsit_cause_connection_reinstatement(conn, 1);
4632 			spin_lock_bh(&sess->conn_lock);
4633 
4634 			iscsit_dec_conn_usage_count(conn);
4635 			if (is_last == 0)
4636 				iscsit_dec_conn_usage_count(conn_tmp);
4637 			conn_count--;
4638 		}
4639 	} else {
4640 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4641 			iscsit_cause_connection_reinstatement(conn, 0);
4642 	}
4643 
4644 	if (session_sleep && atomic_read(&sess->nconn)) {
4645 		spin_unlock_bh(&sess->conn_lock);
4646 		wait_for_completion(&sess->session_wait_comp);
4647 	} else
4648 		spin_unlock_bh(&sess->conn_lock);
4649 }
4650 
4651 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4652 {
4653 	struct iscsi_session *sess;
4654 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4655 	struct se_session *se_sess, *se_sess_tmp;
4656 	LIST_HEAD(free_list);
4657 	int session_count = 0;
4658 
4659 	spin_lock_bh(&se_tpg->session_lock);
4660 	if (tpg->nsessions && !force) {
4661 		spin_unlock_bh(&se_tpg->session_lock);
4662 		return -1;
4663 	}
4664 
4665 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4666 			sess_list) {
4667 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4668 
4669 		spin_lock(&sess->conn_lock);
4670 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4671 		    atomic_read(&sess->session_logout) ||
4672 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4673 			spin_unlock(&sess->conn_lock);
4674 			continue;
4675 		}
4676 		atomic_set(&sess->session_reinstatement, 1);
4677 		spin_unlock(&sess->conn_lock);
4678 
4679 		list_move_tail(&se_sess->sess_list, &free_list);
4680 	}
4681 	spin_unlock_bh(&se_tpg->session_lock);
4682 
4683 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4684 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4685 
4686 		iscsit_free_session(sess);
4687 		session_count++;
4688 	}
4689 
4690 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4691 			" Group: %hu\n", session_count, tpg->tpgt);
4692 	return 0;
4693 }
4694 
4695 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4696 MODULE_VERSION("4.1.x");
4697 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4698 MODULE_LICENSE("GPL");
4699 
4700 module_init(iscsi_target_init_module);
4701 module_exit(iscsi_target_cleanup_module);
4702