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 <asm/unaligned.h>
28 #include <net/ipv6.h>
29 #include <scsi/scsi_proto.h>
30 #include <scsi/iscsi_proto.h>
31 #include <scsi/scsi_tcq.h>
32 #include <target/target_core_base.h>
33 #include <target/target_core_fabric.h>
34 
35 #include <target/iscsi/iscsi_target_core.h>
36 #include "iscsi_target_parameters.h"
37 #include "iscsi_target_seq_pdu_list.h"
38 #include "iscsi_target_datain_values.h"
39 #include "iscsi_target_erl0.h"
40 #include "iscsi_target_erl1.h"
41 #include "iscsi_target_erl2.h"
42 #include "iscsi_target_login.h"
43 #include "iscsi_target_tmr.h"
44 #include "iscsi_target_tpg.h"
45 #include "iscsi_target_util.h"
46 #include "iscsi_target.h"
47 #include "iscsi_target_device.h"
48 #include <target/iscsi/iscsi_target_stat.h>
49 
50 #include <target/iscsi/iscsi_transport.h>
51 
52 static LIST_HEAD(g_tiqn_list);
53 static LIST_HEAD(g_np_list);
54 static DEFINE_SPINLOCK(tiqn_lock);
55 static DEFINE_MUTEX(np_lock);
56 
57 static struct idr tiqn_idr;
58 struct idr sess_idr;
59 struct mutex auth_id_lock;
60 spinlock_t sess_idr_lock;
61 
62 struct iscsit_global *iscsit_global;
63 
64 struct kmem_cache *lio_qr_cache;
65 struct kmem_cache *lio_dr_cache;
66 struct kmem_cache *lio_ooo_cache;
67 struct kmem_cache *lio_r2t_cache;
68 
69 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
70 			struct iscsi_scsi_req *, u32);
71 
72 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
73 {
74 	struct iscsi_tiqn *tiqn = NULL;
75 
76 	spin_lock(&tiqn_lock);
77 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
78 		if (!strcmp(tiqn->tiqn, buf)) {
79 
80 			spin_lock(&tiqn->tiqn_state_lock);
81 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
82 				tiqn->tiqn_access_count++;
83 				spin_unlock(&tiqn->tiqn_state_lock);
84 				spin_unlock(&tiqn_lock);
85 				return tiqn;
86 			}
87 			spin_unlock(&tiqn->tiqn_state_lock);
88 		}
89 	}
90 	spin_unlock(&tiqn_lock);
91 
92 	return NULL;
93 }
94 
95 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
96 {
97 	spin_lock(&tiqn->tiqn_state_lock);
98 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
99 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
100 		spin_unlock(&tiqn->tiqn_state_lock);
101 		return 0;
102 	}
103 	spin_unlock(&tiqn->tiqn_state_lock);
104 
105 	return -1;
106 }
107 
108 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
109 {
110 	spin_lock(&tiqn->tiqn_state_lock);
111 	tiqn->tiqn_access_count--;
112 	spin_unlock(&tiqn->tiqn_state_lock);
113 }
114 
115 /*
116  * Note that IQN formatting is expected to be done in userspace, and
117  * no explict IQN format checks are done here.
118  */
119 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
120 {
121 	struct iscsi_tiqn *tiqn = NULL;
122 	int ret;
123 
124 	if (strlen(buf) >= ISCSI_IQN_LEN) {
125 		pr_err("Target IQN exceeds %d bytes\n",
126 				ISCSI_IQN_LEN);
127 		return ERR_PTR(-EINVAL);
128 	}
129 
130 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
131 	if (!tiqn) {
132 		pr_err("Unable to allocate struct iscsi_tiqn\n");
133 		return ERR_PTR(-ENOMEM);
134 	}
135 
136 	sprintf(tiqn->tiqn, "%s", buf);
137 	INIT_LIST_HEAD(&tiqn->tiqn_list);
138 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
139 	spin_lock_init(&tiqn->tiqn_state_lock);
140 	spin_lock_init(&tiqn->tiqn_tpg_lock);
141 	spin_lock_init(&tiqn->sess_err_stats.lock);
142 	spin_lock_init(&tiqn->login_stats.lock);
143 	spin_lock_init(&tiqn->logout_stats.lock);
144 
145 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
146 
147 	idr_preload(GFP_KERNEL);
148 	spin_lock(&tiqn_lock);
149 
150 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
151 	if (ret < 0) {
152 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
153 		spin_unlock(&tiqn_lock);
154 		idr_preload_end();
155 		kfree(tiqn);
156 		return ERR_PTR(ret);
157 	}
158 	tiqn->tiqn_index = ret;
159 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
160 
161 	spin_unlock(&tiqn_lock);
162 	idr_preload_end();
163 
164 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
165 
166 	return tiqn;
167 
168 }
169 
170 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
171 {
172 	/*
173 	 * Wait for accesses to said struct iscsi_tiqn to end.
174 	 */
175 	spin_lock(&tiqn->tiqn_state_lock);
176 	while (tiqn->tiqn_access_count != 0) {
177 		spin_unlock(&tiqn->tiqn_state_lock);
178 		msleep(10);
179 		spin_lock(&tiqn->tiqn_state_lock);
180 	}
181 	spin_unlock(&tiqn->tiqn_state_lock);
182 }
183 
184 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
185 {
186 	/*
187 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
188 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
189 	 * attempts to access this struct iscsi_tiqn will fail from both transport
190 	 * fabric and control code paths.
191 	 */
192 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
193 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
194 		return;
195 	}
196 
197 	iscsit_wait_for_tiqn(tiqn);
198 
199 	spin_lock(&tiqn_lock);
200 	list_del(&tiqn->tiqn_list);
201 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
202 	spin_unlock(&tiqn_lock);
203 
204 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
205 			tiqn->tiqn);
206 	kfree(tiqn);
207 }
208 
209 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
210 {
211 	int ret;
212 	/*
213 	 * Determine if the network portal is accepting storage traffic.
214 	 */
215 	spin_lock_bh(&np->np_thread_lock);
216 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
217 		spin_unlock_bh(&np->np_thread_lock);
218 		return -1;
219 	}
220 	spin_unlock_bh(&np->np_thread_lock);
221 	/*
222 	 * Determine if the portal group is accepting storage traffic.
223 	 */
224 	spin_lock_bh(&tpg->tpg_state_lock);
225 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
226 		spin_unlock_bh(&tpg->tpg_state_lock);
227 		return -1;
228 	}
229 	spin_unlock_bh(&tpg->tpg_state_lock);
230 
231 	/*
232 	 * Here we serialize access across the TIQN+TPG Tuple.
233 	 */
234 	ret = down_interruptible(&tpg->np_login_sem);
235 	if (ret != 0)
236 		return -1;
237 
238 	spin_lock_bh(&tpg->tpg_state_lock);
239 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
240 		spin_unlock_bh(&tpg->tpg_state_lock);
241 		up(&tpg->np_login_sem);
242 		return -1;
243 	}
244 	spin_unlock_bh(&tpg->tpg_state_lock);
245 
246 	return 0;
247 }
248 
249 void iscsit_login_kref_put(struct kref *kref)
250 {
251 	struct iscsi_tpg_np *tpg_np = container_of(kref,
252 				struct iscsi_tpg_np, tpg_np_kref);
253 
254 	complete(&tpg_np->tpg_np_comp);
255 }
256 
257 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
258 		       struct iscsi_tpg_np *tpg_np)
259 {
260 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
261 
262 	up(&tpg->np_login_sem);
263 
264 	if (tpg_np)
265 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
266 
267 	if (tiqn)
268 		iscsit_put_tiqn_for_login(tiqn);
269 
270 	return 0;
271 }
272 
273 bool iscsit_check_np_match(
274 	struct sockaddr_storage *sockaddr,
275 	struct iscsi_np *np,
276 	int network_transport)
277 {
278 	struct sockaddr_in *sock_in, *sock_in_e;
279 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
280 	bool ip_match = false;
281 	u16 port, port_e;
282 
283 	if (sockaddr->ss_family == AF_INET6) {
284 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
285 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
286 
287 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
288 			    &sock_in6_e->sin6_addr.in6_u,
289 			    sizeof(struct in6_addr)))
290 			ip_match = true;
291 
292 		port = ntohs(sock_in6->sin6_port);
293 		port_e = ntohs(sock_in6_e->sin6_port);
294 	} else {
295 		sock_in = (struct sockaddr_in *)sockaddr;
296 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
297 
298 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
299 			ip_match = true;
300 
301 		port = ntohs(sock_in->sin_port);
302 		port_e = ntohs(sock_in_e->sin_port);
303 	}
304 
305 	if (ip_match && (port_e == port) &&
306 	    (np->np_network_transport == network_transport))
307 		return true;
308 
309 	return false;
310 }
311 
312 /*
313  * Called with mutex np_lock held
314  */
315 static struct iscsi_np *iscsit_get_np(
316 	struct sockaddr_storage *sockaddr,
317 	int network_transport)
318 {
319 	struct iscsi_np *np;
320 	bool match;
321 
322 	list_for_each_entry(np, &g_np_list, np_list) {
323 		spin_lock_bh(&np->np_thread_lock);
324 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
325 			spin_unlock_bh(&np->np_thread_lock);
326 			continue;
327 		}
328 
329 		match = iscsit_check_np_match(sockaddr, np, network_transport);
330 		if (match) {
331 			/*
332 			 * Increment the np_exports reference count now to
333 			 * prevent iscsit_del_np() below from being called
334 			 * while iscsi_tpg_add_network_portal() is called.
335 			 */
336 			np->np_exports++;
337 			spin_unlock_bh(&np->np_thread_lock);
338 			return np;
339 		}
340 		spin_unlock_bh(&np->np_thread_lock);
341 	}
342 
343 	return NULL;
344 }
345 
346 struct iscsi_np *iscsit_add_np(
347 	struct sockaddr_storage *sockaddr,
348 	int network_transport)
349 {
350 	struct iscsi_np *np;
351 	int ret;
352 
353 	mutex_lock(&np_lock);
354 
355 	/*
356 	 * Locate the existing struct iscsi_np if already active..
357 	 */
358 	np = iscsit_get_np(sockaddr, network_transport);
359 	if (np) {
360 		mutex_unlock(&np_lock);
361 		return np;
362 	}
363 
364 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
365 	if (!np) {
366 		pr_err("Unable to allocate memory for struct iscsi_np\n");
367 		mutex_unlock(&np_lock);
368 		return ERR_PTR(-ENOMEM);
369 	}
370 
371 	np->np_flags |= NPF_IP_NETWORK;
372 	np->np_network_transport = network_transport;
373 	spin_lock_init(&np->np_thread_lock);
374 	init_completion(&np->np_restart_comp);
375 	INIT_LIST_HEAD(&np->np_list);
376 
377 	ret = iscsi_target_setup_login_socket(np, sockaddr);
378 	if (ret != 0) {
379 		kfree(np);
380 		mutex_unlock(&np_lock);
381 		return ERR_PTR(ret);
382 	}
383 
384 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
385 	if (IS_ERR(np->np_thread)) {
386 		pr_err("Unable to create kthread: iscsi_np\n");
387 		ret = PTR_ERR(np->np_thread);
388 		kfree(np);
389 		mutex_unlock(&np_lock);
390 		return ERR_PTR(ret);
391 	}
392 	/*
393 	 * Increment the np_exports reference count now to prevent
394 	 * iscsit_del_np() below from being run while a new call to
395 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
396 	 * active.  We don't need to hold np->np_thread_lock at this
397 	 * point because iscsi_np has not been added to g_np_list yet.
398 	 */
399 	np->np_exports = 1;
400 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
401 
402 	list_add_tail(&np->np_list, &g_np_list);
403 	mutex_unlock(&np_lock);
404 
405 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
406 		&np->np_sockaddr, np->np_transport->name);
407 
408 	return np;
409 }
410 
411 int iscsit_reset_np_thread(
412 	struct iscsi_np *np,
413 	struct iscsi_tpg_np *tpg_np,
414 	struct iscsi_portal_group *tpg,
415 	bool shutdown)
416 {
417 	spin_lock_bh(&np->np_thread_lock);
418 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
419 		spin_unlock_bh(&np->np_thread_lock);
420 		return 0;
421 	}
422 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
423 
424 	if (np->np_thread) {
425 		spin_unlock_bh(&np->np_thread_lock);
426 		send_sig(SIGINT, np->np_thread, 1);
427 		wait_for_completion(&np->np_restart_comp);
428 		spin_lock_bh(&np->np_thread_lock);
429 	}
430 	spin_unlock_bh(&np->np_thread_lock);
431 
432 	if (tpg_np && shutdown) {
433 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
434 
435 		wait_for_completion(&tpg_np->tpg_np_comp);
436 	}
437 
438 	return 0;
439 }
440 
441 static void iscsit_free_np(struct iscsi_np *np)
442 {
443 	if (np->np_socket)
444 		sock_release(np->np_socket);
445 }
446 
447 int iscsit_del_np(struct iscsi_np *np)
448 {
449 	spin_lock_bh(&np->np_thread_lock);
450 	np->np_exports--;
451 	if (np->np_exports) {
452 		np->enabled = true;
453 		spin_unlock_bh(&np->np_thread_lock);
454 		return 0;
455 	}
456 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
457 	spin_unlock_bh(&np->np_thread_lock);
458 
459 	if (np->np_thread) {
460 		/*
461 		 * We need to send the signal to wakeup Linux/Net
462 		 * which may be sleeping in sock_accept()..
463 		 */
464 		send_sig(SIGINT, np->np_thread, 1);
465 		kthread_stop(np->np_thread);
466 		np->np_thread = NULL;
467 	}
468 
469 	np->np_transport->iscsit_free_np(np);
470 
471 	mutex_lock(&np_lock);
472 	list_del(&np->np_list);
473 	mutex_unlock(&np_lock);
474 
475 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
476 		&np->np_sockaddr, np->np_transport->name);
477 
478 	iscsit_put_transport(np->np_transport);
479 	kfree(np);
480 	return 0;
481 }
482 
483 static void iscsit_get_rx_pdu(struct iscsi_conn *);
484 
485 int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
486 {
487 	iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
488 	return 0;
489 }
490 EXPORT_SYMBOL(iscsit_queue_rsp);
491 
492 void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
493 {
494 	bool scsi_cmd = (cmd->iscsi_opcode == ISCSI_OP_SCSI_CMD);
495 
496 	spin_lock_bh(&conn->cmd_lock);
497 	if (!list_empty(&cmd->i_conn_node) &&
498 	    !(cmd->se_cmd.transport_state & CMD_T_FABRIC_STOP))
499 		list_del_init(&cmd->i_conn_node);
500 	spin_unlock_bh(&conn->cmd_lock);
501 
502 	__iscsit_free_cmd(cmd, scsi_cmd, true);
503 }
504 EXPORT_SYMBOL(iscsit_aborted_task);
505 
506 static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
507 				      u32, u32, u8 *, u8 *);
508 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *);
509 
510 static int
511 iscsit_xmit_nondatain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
512 			  const void *data_buf, u32 data_buf_len)
513 {
514 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
515 	struct kvec *iov;
516 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
517 	int ret;
518 
519 	iov = &cmd->iov_misc[0];
520 	iov[niov].iov_base	= cmd->pdu;
521 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
522 
523 	if (conn->conn_ops->HeaderDigest) {
524 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
525 
526 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
527 					  ISCSI_HDR_LEN, 0, NULL,
528 					  (u8 *)header_digest);
529 
530 		iov[0].iov_len += ISCSI_CRC_LEN;
531 		tx_size += ISCSI_CRC_LEN;
532 		pr_debug("Attaching CRC32C HeaderDigest"
533 			 " to opcode 0x%x 0x%08x\n",
534 			 hdr->opcode, *header_digest);
535 	}
536 
537 	if (data_buf_len) {
538 		u32 padding = ((-data_buf_len) & 3);
539 
540 		iov[niov].iov_base	= (void *)data_buf;
541 		iov[niov++].iov_len	= data_buf_len;
542 		tx_size += data_buf_len;
543 
544 		if (padding != 0) {
545 			iov[niov].iov_base = &cmd->pad_bytes;
546 			iov[niov++].iov_len = padding;
547 			tx_size += padding;
548 			pr_debug("Attaching %u additional"
549 				 " padding bytes.\n", padding);
550 		}
551 
552 		if (conn->conn_ops->DataDigest) {
553 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
554 						  data_buf, data_buf_len,
555 						  padding,
556 						  (u8 *)&cmd->pad_bytes,
557 						  (u8 *)&cmd->data_crc);
558 
559 			iov[niov].iov_base = &cmd->data_crc;
560 			iov[niov++].iov_len = ISCSI_CRC_LEN;
561 			tx_size += ISCSI_CRC_LEN;
562 			pr_debug("Attached DataDigest for %u"
563 				 " bytes opcode 0x%x, CRC 0x%08x\n",
564 				 data_buf_len, hdr->opcode, cmd->data_crc);
565 		}
566 	}
567 
568 	cmd->iov_misc_count = niov;
569 	cmd->tx_size = tx_size;
570 
571 	ret = iscsit_send_tx_data(cmd, conn, 1);
572 	if (ret < 0) {
573 		iscsit_tx_thread_wait_for_tcp(conn);
574 		return ret;
575 	}
576 
577 	return 0;
578 }
579 
580 static int iscsit_map_iovec(struct iscsi_cmd *, struct kvec *, u32, u32);
581 static void iscsit_unmap_iovec(struct iscsi_cmd *);
582 static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsi_cmd *,
583 				    u32, u32, u32, u8 *);
584 static int
585 iscsit_xmit_datain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
586 		       const struct iscsi_datain *datain)
587 {
588 	struct kvec *iov;
589 	u32 iov_count = 0, tx_size = 0;
590 	int ret, iov_ret;
591 
592 	iov = &cmd->iov_data[0];
593 	iov[iov_count].iov_base	= cmd->pdu;
594 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
595 	tx_size += ISCSI_HDR_LEN;
596 
597 	if (conn->conn_ops->HeaderDigest) {
598 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
599 
600 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
601 					  ISCSI_HDR_LEN, 0, NULL,
602 					  (u8 *)header_digest);
603 
604 		iov[0].iov_len += ISCSI_CRC_LEN;
605 		tx_size += ISCSI_CRC_LEN;
606 
607 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
608 			 *header_digest);
609 	}
610 
611 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
612 				   datain->offset, datain->length);
613 	if (iov_ret < 0)
614 		return -1;
615 
616 	iov_count += iov_ret;
617 	tx_size += datain->length;
618 
619 	cmd->padding = ((-datain->length) & 3);
620 	if (cmd->padding) {
621 		iov[iov_count].iov_base		= cmd->pad_bytes;
622 		iov[iov_count++].iov_len	= cmd->padding;
623 		tx_size += cmd->padding;
624 
625 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
626 	}
627 
628 	if (conn->conn_ops->DataDigest) {
629 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
630 							 cmd, datain->offset,
631 							 datain->length,
632 							 cmd->padding,
633 							 cmd->pad_bytes);
634 
635 		iov[iov_count].iov_base	= &cmd->data_crc;
636 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
637 		tx_size += ISCSI_CRC_LEN;
638 
639 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
640 			 datain->length + cmd->padding, cmd->data_crc);
641 	}
642 
643 	cmd->iov_data_count = iov_count;
644 	cmd->tx_size = tx_size;
645 
646 	ret = iscsit_fe_sendpage_sg(cmd, conn);
647 
648 	iscsit_unmap_iovec(cmd);
649 
650 	if (ret < 0) {
651 		iscsit_tx_thread_wait_for_tcp(conn);
652 		return ret;
653 	}
654 
655 	return 0;
656 }
657 
658 static int iscsit_xmit_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
659 			   struct iscsi_datain_req *dr, const void *buf,
660 			   u32 buf_len)
661 {
662 	if (dr)
663 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
664 	else
665 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
666 }
667 
668 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
669 {
670 	return TARGET_PROT_NORMAL;
671 }
672 
673 static struct iscsit_transport iscsi_target_transport = {
674 	.name			= "iSCSI/TCP",
675 	.transport_type		= ISCSI_TCP,
676 	.rdma_shutdown		= false,
677 	.owner			= NULL,
678 	.iscsit_setup_np	= iscsit_setup_np,
679 	.iscsit_accept_np	= iscsit_accept_np,
680 	.iscsit_free_np		= iscsit_free_np,
681 	.iscsit_get_login_rx	= iscsit_get_login_rx,
682 	.iscsit_put_login_tx	= iscsit_put_login_tx,
683 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
684 	.iscsit_immediate_queue	= iscsit_immediate_queue,
685 	.iscsit_response_queue	= iscsit_response_queue,
686 	.iscsit_queue_data_in	= iscsit_queue_rsp,
687 	.iscsit_queue_status	= iscsit_queue_rsp,
688 	.iscsit_aborted_task	= iscsit_aborted_task,
689 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
690 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
691 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
692 };
693 
694 static int __init iscsi_target_init_module(void)
695 {
696 	int ret = 0, size;
697 
698 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
699 
700 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
701 	if (!iscsit_global) {
702 		pr_err("Unable to allocate memory for iscsit_global\n");
703 		return -1;
704 	}
705 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
706 	mutex_init(&auth_id_lock);
707 	spin_lock_init(&sess_idr_lock);
708 	idr_init(&tiqn_idr);
709 	idr_init(&sess_idr);
710 
711 	ret = target_register_template(&iscsi_ops);
712 	if (ret)
713 		goto out;
714 
715 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
716 	iscsit_global->ts_bitmap = vzalloc(size);
717 	if (!iscsit_global->ts_bitmap) {
718 		pr_err("Unable to allocate iscsit_global->ts_bitmap\n");
719 		goto configfs_out;
720 	}
721 
722 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
723 			sizeof(struct iscsi_queue_req),
724 			__alignof__(struct iscsi_queue_req), 0, NULL);
725 	if (!lio_qr_cache) {
726 		pr_err("nable to kmem_cache_create() for"
727 				" lio_qr_cache\n");
728 		goto bitmap_out;
729 	}
730 
731 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
732 			sizeof(struct iscsi_datain_req),
733 			__alignof__(struct iscsi_datain_req), 0, NULL);
734 	if (!lio_dr_cache) {
735 		pr_err("Unable to kmem_cache_create() for"
736 				" lio_dr_cache\n");
737 		goto qr_out;
738 	}
739 
740 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
741 			sizeof(struct iscsi_ooo_cmdsn),
742 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
743 	if (!lio_ooo_cache) {
744 		pr_err("Unable to kmem_cache_create() for"
745 				" lio_ooo_cache\n");
746 		goto dr_out;
747 	}
748 
749 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
750 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
751 			0, NULL);
752 	if (!lio_r2t_cache) {
753 		pr_err("Unable to kmem_cache_create() for"
754 				" lio_r2t_cache\n");
755 		goto ooo_out;
756 	}
757 
758 	iscsit_register_transport(&iscsi_target_transport);
759 
760 	if (iscsit_load_discovery_tpg() < 0)
761 		goto r2t_out;
762 
763 	return ret;
764 r2t_out:
765 	iscsit_unregister_transport(&iscsi_target_transport);
766 	kmem_cache_destroy(lio_r2t_cache);
767 ooo_out:
768 	kmem_cache_destroy(lio_ooo_cache);
769 dr_out:
770 	kmem_cache_destroy(lio_dr_cache);
771 qr_out:
772 	kmem_cache_destroy(lio_qr_cache);
773 bitmap_out:
774 	vfree(iscsit_global->ts_bitmap);
775 configfs_out:
776 	/* XXX: this probably wants it to be it's own unwind step.. */
777 	if (iscsit_global->discovery_tpg)
778 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
779 	target_unregister_template(&iscsi_ops);
780 out:
781 	kfree(iscsit_global);
782 	return -ENOMEM;
783 }
784 
785 static void __exit iscsi_target_cleanup_module(void)
786 {
787 	iscsit_release_discovery_tpg();
788 	iscsit_unregister_transport(&iscsi_target_transport);
789 	kmem_cache_destroy(lio_qr_cache);
790 	kmem_cache_destroy(lio_dr_cache);
791 	kmem_cache_destroy(lio_ooo_cache);
792 	kmem_cache_destroy(lio_r2t_cache);
793 
794 	/*
795 	 * Shutdown discovery sessions and disable discovery TPG
796 	 */
797 	if (iscsit_global->discovery_tpg)
798 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
799 
800 	target_unregister_template(&iscsi_ops);
801 
802 	vfree(iscsit_global->ts_bitmap);
803 	kfree(iscsit_global);
804 }
805 
806 int iscsit_add_reject(
807 	struct iscsi_conn *conn,
808 	u8 reason,
809 	unsigned char *buf)
810 {
811 	struct iscsi_cmd *cmd;
812 
813 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
814 	if (!cmd)
815 		return -1;
816 
817 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
818 	cmd->reject_reason = reason;
819 
820 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
821 	if (!cmd->buf_ptr) {
822 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
823 		iscsit_free_cmd(cmd, false);
824 		return -1;
825 	}
826 
827 	spin_lock_bh(&conn->cmd_lock);
828 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
829 	spin_unlock_bh(&conn->cmd_lock);
830 
831 	cmd->i_state = ISTATE_SEND_REJECT;
832 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
833 
834 	return -1;
835 }
836 EXPORT_SYMBOL(iscsit_add_reject);
837 
838 static int iscsit_add_reject_from_cmd(
839 	struct iscsi_cmd *cmd,
840 	u8 reason,
841 	bool add_to_conn,
842 	unsigned char *buf)
843 {
844 	struct iscsi_conn *conn;
845 
846 	if (!cmd->conn) {
847 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
848 				cmd->init_task_tag);
849 		return -1;
850 	}
851 	conn = cmd->conn;
852 
853 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
854 	cmd->reject_reason = reason;
855 
856 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
857 	if (!cmd->buf_ptr) {
858 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
859 		iscsit_free_cmd(cmd, false);
860 		return -1;
861 	}
862 
863 	if (add_to_conn) {
864 		spin_lock_bh(&conn->cmd_lock);
865 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
866 		spin_unlock_bh(&conn->cmd_lock);
867 	}
868 
869 	cmd->i_state = ISTATE_SEND_REJECT;
870 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
871 	/*
872 	 * Perform the kref_put now if se_cmd has already been setup by
873 	 * scsit_setup_scsi_cmd()
874 	 */
875 	if (cmd->se_cmd.se_tfo != NULL) {
876 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
877 		target_put_sess_cmd(&cmd->se_cmd);
878 	}
879 	return -1;
880 }
881 
882 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
883 				 unsigned char *buf)
884 {
885 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
886 }
887 
888 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
889 {
890 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
891 }
892 EXPORT_SYMBOL(iscsit_reject_cmd);
893 
894 /*
895  * Map some portion of the allocated scatterlist to an iovec, suitable for
896  * kernel sockets to copy data in/out.
897  */
898 static int iscsit_map_iovec(
899 	struct iscsi_cmd *cmd,
900 	struct kvec *iov,
901 	u32 data_offset,
902 	u32 data_length)
903 {
904 	u32 i = 0;
905 	struct scatterlist *sg;
906 	unsigned int page_off;
907 
908 	/*
909 	 * We know each entry in t_data_sg contains a page.
910 	 */
911 	u32 ent = data_offset / PAGE_SIZE;
912 
913 	if (ent >= cmd->se_cmd.t_data_nents) {
914 		pr_err("Initial page entry out-of-bounds\n");
915 		return -1;
916 	}
917 
918 	sg = &cmd->se_cmd.t_data_sg[ent];
919 	page_off = (data_offset % PAGE_SIZE);
920 
921 	cmd->first_data_sg = sg;
922 	cmd->first_data_sg_off = page_off;
923 
924 	while (data_length) {
925 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
926 
927 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
928 		iov[i].iov_len = cur_len;
929 
930 		data_length -= cur_len;
931 		page_off = 0;
932 		sg = sg_next(sg);
933 		i++;
934 	}
935 
936 	cmd->kmapped_nents = i;
937 
938 	return i;
939 }
940 
941 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
942 {
943 	u32 i;
944 	struct scatterlist *sg;
945 
946 	sg = cmd->first_data_sg;
947 
948 	for (i = 0; i < cmd->kmapped_nents; i++)
949 		kunmap(sg_page(&sg[i]));
950 }
951 
952 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
953 {
954 	LIST_HEAD(ack_list);
955 	struct iscsi_cmd *cmd, *cmd_p;
956 
957 	conn->exp_statsn = exp_statsn;
958 
959 	if (conn->sess->sess_ops->RDMAExtensions)
960 		return;
961 
962 	spin_lock_bh(&conn->cmd_lock);
963 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
964 		spin_lock(&cmd->istate_lock);
965 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
966 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
967 			cmd->i_state = ISTATE_REMOVE;
968 			spin_unlock(&cmd->istate_lock);
969 			list_move_tail(&cmd->i_conn_node, &ack_list);
970 			continue;
971 		}
972 		spin_unlock(&cmd->istate_lock);
973 	}
974 	spin_unlock_bh(&conn->cmd_lock);
975 
976 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
977 		list_del_init(&cmd->i_conn_node);
978 		iscsit_free_cmd(cmd, false);
979 	}
980 }
981 
982 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
983 {
984 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
985 
986 	iov_count += ISCSI_IOV_DATA_BUFFER;
987 
988 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
989 	if (!cmd->iov_data) {
990 		pr_err("Unable to allocate cmd->iov_data\n");
991 		return -ENOMEM;
992 	}
993 
994 	cmd->orig_iov_data_count = iov_count;
995 	return 0;
996 }
997 
998 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
999 			  unsigned char *buf)
1000 {
1001 	int data_direction, payload_length;
1002 	struct iscsi_scsi_req *hdr;
1003 	int iscsi_task_attr;
1004 	int sam_task_attr;
1005 
1006 	atomic_long_inc(&conn->sess->cmd_pdus);
1007 
1008 	hdr			= (struct iscsi_scsi_req *) buf;
1009 	payload_length		= ntoh24(hdr->dlength);
1010 
1011 	/* FIXME; Add checks for AdditionalHeaderSegment */
1012 
1013 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1014 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1015 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1016 				" not set. Bad iSCSI Initiator.\n");
1017 		return iscsit_add_reject_cmd(cmd,
1018 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1019 	}
1020 
1021 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1022 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1023 		/*
1024 		 * From RFC-3720 Section 10.3.1:
1025 		 *
1026 		 * "Either or both of R and W MAY be 1 when either the
1027 		 *  Expected Data Transfer Length and/or Bidirectional Read
1028 		 *  Expected Data Transfer Length are 0"
1029 		 *
1030 		 * For this case, go ahead and clear the unnecssary bits
1031 		 * to avoid any confusion with ->data_direction.
1032 		 */
1033 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1034 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1035 
1036 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1037 			" set when Expected Data Transfer Length is 0 for"
1038 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1039 	}
1040 
1041 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1042 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1043 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1044 			" MUST be set if Expected Data Transfer Length is not 0."
1045 			" Bad iSCSI Initiator\n");
1046 		return iscsit_add_reject_cmd(cmd,
1047 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1048 	}
1049 
1050 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1051 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1052 		pr_err("Bidirectional operations not supported!\n");
1053 		return iscsit_add_reject_cmd(cmd,
1054 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1055 	}
1056 
1057 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1058 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1059 				" Scsi Command PDU.\n");
1060 		return iscsit_add_reject_cmd(cmd,
1061 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1062 	}
1063 
1064 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1065 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1066 			" protocol error.\n", payload_length);
1067 		return iscsit_add_reject_cmd(cmd,
1068 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1069 	}
1070 
1071 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1072 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1073 		pr_err("Expected Data Transfer Length and Length of"
1074 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1075 			" bit is not set protocol error\n");
1076 		return iscsit_add_reject_cmd(cmd,
1077 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1078 	}
1079 
1080 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1081 		pr_err("DataSegmentLength: %u is greater than"
1082 			" EDTL: %u, protocol error.\n", payload_length,
1083 				hdr->data_length);
1084 		return iscsit_add_reject_cmd(cmd,
1085 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1086 	}
1087 
1088 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1089 		pr_err("DataSegmentLength: %u is greater than"
1090 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1091 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1092 		return iscsit_add_reject_cmd(cmd,
1093 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1094 	}
1095 
1096 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1097 		pr_err("DataSegmentLength: %u is greater than"
1098 			" FirstBurstLength: %u, protocol error.\n",
1099 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1100 		return iscsit_add_reject_cmd(cmd,
1101 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1102 	}
1103 
1104 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1105 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1106 			  DMA_NONE;
1107 
1108 	cmd->data_direction = data_direction;
1109 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1110 	/*
1111 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1112 	 */
1113 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1114 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1115 		sam_task_attr = TCM_SIMPLE_TAG;
1116 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1117 		sam_task_attr = TCM_ORDERED_TAG;
1118 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1119 		sam_task_attr = TCM_HEAD_TAG;
1120 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1121 		sam_task_attr = TCM_ACA_TAG;
1122 	else {
1123 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1124 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1125 		sam_task_attr = TCM_SIMPLE_TAG;
1126 	}
1127 
1128 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1129 	cmd->i_state		= ISTATE_NEW_CMD;
1130 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1131 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1132 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1133 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1134 	if (cmd->unsolicited_data)
1135 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1136 
1137 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1138 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1139 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1140 	else
1141 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1142 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1143 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1144 	cmd->first_burst_len	= payload_length;
1145 
1146 	if (!conn->sess->sess_ops->RDMAExtensions &&
1147 	     cmd->data_direction == DMA_FROM_DEVICE) {
1148 		struct iscsi_datain_req *dr;
1149 
1150 		dr = iscsit_allocate_datain_req();
1151 		if (!dr)
1152 			return iscsit_add_reject_cmd(cmd,
1153 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1154 
1155 		iscsit_attach_datain_req(cmd, dr);
1156 	}
1157 
1158 	/*
1159 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1160 	 */
1161 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1162 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1163 			cmd->data_direction, sam_task_attr,
1164 			cmd->sense_buffer + 2);
1165 
1166 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1167 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1168 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1169 		conn->cid);
1170 
1171 	target_get_sess_cmd(&cmd->se_cmd, true);
1172 
1173 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
1174 						     scsilun_to_int(&hdr->lun));
1175 	if (cmd->sense_reason)
1176 		goto attach_cmd;
1177 
1178 	/* only used for printks or comparing with ->ref_task_tag */
1179 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1180 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
1181 	if (cmd->sense_reason) {
1182 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1183 			return iscsit_add_reject_cmd(cmd,
1184 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1185 		}
1186 
1187 		goto attach_cmd;
1188 	}
1189 
1190 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1191 		return iscsit_add_reject_cmd(cmd,
1192 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1193 	}
1194 
1195 attach_cmd:
1196 	spin_lock_bh(&conn->cmd_lock);
1197 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1198 	spin_unlock_bh(&conn->cmd_lock);
1199 	/*
1200 	 * Check if we need to delay processing because of ALUA
1201 	 * Active/NonOptimized primary access state..
1202 	 */
1203 	core_alua_check_nonop_delay(&cmd->se_cmd);
1204 
1205 	return 0;
1206 }
1207 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1208 
1209 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1210 {
1211 	iscsit_set_dataout_sequence_values(cmd);
1212 
1213 	spin_lock_bh(&cmd->dataout_timeout_lock);
1214 	iscsit_start_dataout_timer(cmd, cmd->conn);
1215 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1216 }
1217 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1218 
1219 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1220 			    struct iscsi_scsi_req *hdr)
1221 {
1222 	int cmdsn_ret = 0;
1223 	/*
1224 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1225 	 * the Immediate Bit is not set, and no Immediate
1226 	 * Data is attached.
1227 	 *
1228 	 * A PDU/CmdSN carrying Immediate Data can only
1229 	 * be processed after the DataCRC has passed.
1230 	 * If the DataCRC fails, the CmdSN MUST NOT
1231 	 * be acknowledged. (See below)
1232 	 */
1233 	if (!cmd->immediate_data) {
1234 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1235 					(unsigned char *)hdr, hdr->cmdsn);
1236 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1237 			return -1;
1238 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1239 			target_put_sess_cmd(&cmd->se_cmd);
1240 			return 0;
1241 		}
1242 	}
1243 
1244 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1245 
1246 	/*
1247 	 * If no Immediate Data is attached, it's OK to return now.
1248 	 */
1249 	if (!cmd->immediate_data) {
1250 		if (!cmd->sense_reason && cmd->unsolicited_data)
1251 			iscsit_set_unsoliticed_dataout(cmd);
1252 		if (!cmd->sense_reason)
1253 			return 0;
1254 
1255 		target_put_sess_cmd(&cmd->se_cmd);
1256 		return 0;
1257 	}
1258 
1259 	/*
1260 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1261 	 * execution.  These exceptions are processed in CmdSN order using
1262 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1263 	 */
1264 	if (cmd->sense_reason) {
1265 		if (cmd->reject_reason)
1266 			return 0;
1267 
1268 		return 1;
1269 	}
1270 	/*
1271 	 * Call directly into transport_generic_new_cmd() to perform
1272 	 * the backend memory allocation.
1273 	 */
1274 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1275 	if (cmd->sense_reason)
1276 		return 1;
1277 
1278 	return 0;
1279 }
1280 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1281 
1282 static int
1283 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1284 			  bool dump_payload)
1285 {
1286 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1287 	/*
1288 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1289 	 */
1290 	if (dump_payload)
1291 		goto after_immediate_data;
1292 
1293 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1294 					cmd->first_burst_len);
1295 after_immediate_data:
1296 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1297 		/*
1298 		 * A PDU/CmdSN carrying Immediate Data passed
1299 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1300 		 * Immediate Bit is not set.
1301 		 */
1302 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1303 					(unsigned char *)hdr, hdr->cmdsn);
1304 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1305 			return -1;
1306 
1307 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1308 			int rc;
1309 
1310 			rc = iscsit_dump_data_payload(cmd->conn,
1311 						      cmd->first_burst_len, 1);
1312 			target_put_sess_cmd(&cmd->se_cmd);
1313 			return rc;
1314 		} else if (cmd->unsolicited_data)
1315 			iscsit_set_unsoliticed_dataout(cmd);
1316 
1317 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1318 		/*
1319 		 * Immediate Data failed DataCRC and ERL>=1,
1320 		 * silently drop this PDU and let the initiator
1321 		 * plug the CmdSN gap.
1322 		 *
1323 		 * FIXME: Send Unsolicited NOPIN with reserved
1324 		 * TTT here to help the initiator figure out
1325 		 * the missing CmdSN, although they should be
1326 		 * intelligent enough to determine the missing
1327 		 * CmdSN and issue a retry to plug the sequence.
1328 		 */
1329 		cmd->i_state = ISTATE_REMOVE;
1330 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1331 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1332 		return -1;
1333 
1334 	return 0;
1335 }
1336 
1337 static int
1338 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1339 			   unsigned char *buf)
1340 {
1341 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1342 	int rc, immed_data;
1343 	bool dump_payload = false;
1344 
1345 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1346 	if (rc < 0)
1347 		return 0;
1348 	/*
1349 	 * Allocation iovecs needed for struct socket operations for
1350 	 * traditional iSCSI block I/O.
1351 	 */
1352 	if (iscsit_allocate_iovecs(cmd) < 0) {
1353 		return iscsit_reject_cmd(cmd,
1354 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1355 	}
1356 	immed_data = cmd->immediate_data;
1357 
1358 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1359 	if (rc < 0)
1360 		return rc;
1361 	else if (rc > 0)
1362 		dump_payload = true;
1363 
1364 	if (!immed_data)
1365 		return 0;
1366 
1367 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1368 }
1369 
1370 static u32 iscsit_do_crypto_hash_sg(
1371 	struct ahash_request *hash,
1372 	struct iscsi_cmd *cmd,
1373 	u32 data_offset,
1374 	u32 data_length,
1375 	u32 padding,
1376 	u8 *pad_bytes)
1377 {
1378 	u32 data_crc;
1379 	struct scatterlist *sg;
1380 	unsigned int page_off;
1381 
1382 	crypto_ahash_init(hash);
1383 
1384 	sg = cmd->first_data_sg;
1385 	page_off = cmd->first_data_sg_off;
1386 
1387 	while (data_length) {
1388 		u32 cur_len = min_t(u32, data_length, (sg->length - page_off));
1389 
1390 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1391 		crypto_ahash_update(hash);
1392 
1393 		data_length -= cur_len;
1394 		page_off = 0;
1395 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1396 		sg = sg_next(sg);
1397 	}
1398 
1399 	if (padding) {
1400 		struct scatterlist pad_sg;
1401 
1402 		sg_init_one(&pad_sg, pad_bytes, padding);
1403 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1404 					padding);
1405 		crypto_ahash_finup(hash);
1406 	} else {
1407 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1408 		crypto_ahash_final(hash);
1409 	}
1410 
1411 	return data_crc;
1412 }
1413 
1414 static void iscsit_do_crypto_hash_buf(
1415 	struct ahash_request *hash,
1416 	const void *buf,
1417 	u32 payload_length,
1418 	u32 padding,
1419 	u8 *pad_bytes,
1420 	u8 *data_crc)
1421 {
1422 	struct scatterlist sg[2];
1423 
1424 	sg_init_table(sg, ARRAY_SIZE(sg));
1425 	sg_set_buf(sg, buf, payload_length);
1426 	sg_set_buf(sg + 1, pad_bytes, padding);
1427 
1428 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1429 
1430 	crypto_ahash_digest(hash);
1431 }
1432 
1433 int
1434 iscsit_check_dataout_hdr(struct iscsi_conn *conn, unsigned char *buf,
1435 			  struct iscsi_cmd **out_cmd)
1436 {
1437 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1438 	struct iscsi_cmd *cmd = NULL;
1439 	struct se_cmd *se_cmd;
1440 	u32 payload_length = ntoh24(hdr->dlength);
1441 	int rc;
1442 
1443 	if (!payload_length) {
1444 		pr_warn("DataOUT payload is ZERO, ignoring.\n");
1445 		return 0;
1446 	}
1447 
1448 	/* iSCSI write */
1449 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1450 
1451 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1452 		pr_err("DataSegmentLength: %u is greater than"
1453 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1454 			conn->conn_ops->MaxXmitDataSegmentLength);
1455 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1456 					 buf);
1457 	}
1458 
1459 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt,
1460 			payload_length);
1461 	if (!cmd)
1462 		return 0;
1463 
1464 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1465 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1466 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1467 		payload_length, conn->cid);
1468 
1469 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1470 		pr_err("Command ITT: 0x%08x received DataOUT after"
1471 			" last DataOUT received, dumping payload\n",
1472 			cmd->init_task_tag);
1473 		return iscsit_dump_data_payload(conn, payload_length, 1);
1474 	}
1475 
1476 	if (cmd->data_direction != DMA_TO_DEVICE) {
1477 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1478 			" NON-WRITE command.\n", cmd->init_task_tag);
1479 		return iscsit_dump_data_payload(conn, payload_length, 1);
1480 	}
1481 	se_cmd = &cmd->se_cmd;
1482 	iscsit_mod_dataout_timer(cmd);
1483 
1484 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1485 		pr_err("DataOut Offset: %u, Length %u greater than"
1486 			" iSCSI Command EDTL %u, protocol error.\n",
1487 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1488 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1489 	}
1490 
1491 	if (cmd->unsolicited_data) {
1492 		int dump_unsolicited_data = 0;
1493 
1494 		if (conn->sess->sess_ops->InitialR2T) {
1495 			pr_err("Received unexpected unsolicited data"
1496 				" while InitialR2T=Yes, protocol error.\n");
1497 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1498 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1499 			return -1;
1500 		}
1501 		/*
1502 		 * Special case for dealing with Unsolicited DataOUT
1503 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1504 		 * failures;
1505 		 */
1506 
1507 		/* Something's amiss if we're not in WRITE_PENDING state... */
1508 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1509 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1510 			dump_unsolicited_data = 1;
1511 
1512 		if (dump_unsolicited_data) {
1513 			/*
1514 			 * Check if a delayed TASK_ABORTED status needs to
1515 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1516 			 * received with the unsolicited data out.
1517 			 */
1518 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1519 				iscsit_stop_dataout_timer(cmd);
1520 
1521 			transport_check_aborted_status(se_cmd,
1522 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1523 			return iscsit_dump_data_payload(conn, payload_length, 1);
1524 		}
1525 	} else {
1526 		/*
1527 		 * For the normal solicited data path:
1528 		 *
1529 		 * Check for a delayed TASK_ABORTED status and dump any
1530 		 * incoming data out payload if one exists.  Also, when the
1531 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1532 		 * data out sequence, we decrement outstanding_r2ts.  Once
1533 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1534 		 * TASK_ABORTED status.
1535 		 */
1536 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1537 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1538 				if (--cmd->outstanding_r2ts < 1) {
1539 					iscsit_stop_dataout_timer(cmd);
1540 					transport_check_aborted_status(
1541 							se_cmd, 1);
1542 				}
1543 
1544 			return iscsit_dump_data_payload(conn, payload_length, 1);
1545 		}
1546 	}
1547 	/*
1548 	 * Preform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1549 	 * within-command recovery checks before receiving the payload.
1550 	 */
1551 	rc = iscsit_check_pre_dataout(cmd, buf);
1552 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1553 		return 0;
1554 	else if (rc == DATAOUT_CANNOT_RECOVER)
1555 		return -1;
1556 
1557 	*out_cmd = cmd;
1558 	return 0;
1559 }
1560 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1561 
1562 static int
1563 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1564 		   struct iscsi_data *hdr)
1565 {
1566 	struct kvec *iov;
1567 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1568 	u32 payload_length = ntoh24(hdr->dlength);
1569 	int iov_ret, data_crc_failed = 0;
1570 
1571 	rx_size += payload_length;
1572 	iov = &cmd->iov_data[0];
1573 
1574 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1575 				   payload_length);
1576 	if (iov_ret < 0)
1577 		return -1;
1578 
1579 	iov_count += iov_ret;
1580 
1581 	padding = ((-payload_length) & 3);
1582 	if (padding != 0) {
1583 		iov[iov_count].iov_base	= cmd->pad_bytes;
1584 		iov[iov_count++].iov_len = padding;
1585 		rx_size += padding;
1586 		pr_debug("Receiving %u padding bytes.\n", padding);
1587 	}
1588 
1589 	if (conn->conn_ops->DataDigest) {
1590 		iov[iov_count].iov_base = &checksum;
1591 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1592 		rx_size += ISCSI_CRC_LEN;
1593 	}
1594 
1595 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1596 
1597 	iscsit_unmap_iovec(cmd);
1598 
1599 	if (rx_got != rx_size)
1600 		return -1;
1601 
1602 	if (conn->conn_ops->DataDigest) {
1603 		u32 data_crc;
1604 
1605 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1606 						    be32_to_cpu(hdr->offset),
1607 						    payload_length, padding,
1608 						    cmd->pad_bytes);
1609 
1610 		if (checksum != data_crc) {
1611 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1612 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1613 				" does not match computed 0x%08x\n",
1614 				hdr->itt, hdr->offset, payload_length,
1615 				hdr->datasn, checksum, data_crc);
1616 			data_crc_failed = 1;
1617 		} else {
1618 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1619 				" %u bytes of Data Out\n", checksum,
1620 				payload_length);
1621 		}
1622 	}
1623 
1624 	return data_crc_failed;
1625 }
1626 
1627 int
1628 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1629 			     bool data_crc_failed)
1630 {
1631 	struct iscsi_conn *conn = cmd->conn;
1632 	int rc, ooo_cmdsn;
1633 	/*
1634 	 * Increment post receive data and CRC values or perform
1635 	 * within-command recovery.
1636 	 */
1637 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1638 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1639 		return 0;
1640 	else if (rc == DATAOUT_SEND_R2T) {
1641 		iscsit_set_dataout_sequence_values(cmd);
1642 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1643 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1644 		/*
1645 		 * Handle extra special case for out of order
1646 		 * Unsolicited Data Out.
1647 		 */
1648 		spin_lock_bh(&cmd->istate_lock);
1649 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1650 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1651 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1652 		spin_unlock_bh(&cmd->istate_lock);
1653 
1654 		iscsit_stop_dataout_timer(cmd);
1655 		if (ooo_cmdsn)
1656 			return 0;
1657 		target_execute_cmd(&cmd->se_cmd);
1658 		return 0;
1659 	} else /* DATAOUT_CANNOT_RECOVER */
1660 		return -1;
1661 
1662 	return 0;
1663 }
1664 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1665 
1666 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1667 {
1668 	struct iscsi_cmd *cmd = NULL;
1669 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1670 	int rc;
1671 	bool data_crc_failed = false;
1672 
1673 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1674 	if (rc < 0)
1675 		return 0;
1676 	else if (!cmd)
1677 		return 0;
1678 
1679 	rc = iscsit_get_dataout(conn, cmd, hdr);
1680 	if (rc < 0)
1681 		return rc;
1682 	else if (rc > 0)
1683 		data_crc_failed = true;
1684 
1685 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1686 }
1687 
1688 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1689 			 struct iscsi_nopout *hdr)
1690 {
1691 	u32 payload_length = ntoh24(hdr->dlength);
1692 
1693 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1694 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1695 		if (!cmd)
1696 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1697 						 (unsigned char *)hdr);
1698 
1699 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1700 					 (unsigned char *)hdr);
1701 	}
1702 
1703 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1704 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1705 			" not set, protocol error.\n");
1706 		if (!cmd)
1707 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1708 						 (unsigned char *)hdr);
1709 
1710 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1711 					 (unsigned char *)hdr);
1712 	}
1713 
1714 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1715 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1716 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1717 			" error.\n", payload_length,
1718 			conn->conn_ops->MaxXmitDataSegmentLength);
1719 		if (!cmd)
1720 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1721 						 (unsigned char *)hdr);
1722 
1723 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1724 					 (unsigned char *)hdr);
1725 	}
1726 
1727 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1728 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1729 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1730 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1731 		payload_length);
1732 	/*
1733 	 * This is not a response to a Unsolicited NopIN, which means
1734 	 * it can either be a NOPOUT ping request (with a valid ITT),
1735 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1736 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1737 	 * can contain ping data.
1738 	 */
1739 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1740 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1741 		cmd->i_state		= ISTATE_SEND_NOPIN;
1742 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1743 						1 : 0);
1744 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1745 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1746 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1747 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1748 		cmd->data_direction	= DMA_NONE;
1749 	}
1750 
1751 	return 0;
1752 }
1753 EXPORT_SYMBOL(iscsit_setup_nop_out);
1754 
1755 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1756 			   struct iscsi_nopout *hdr)
1757 {
1758 	struct iscsi_cmd *cmd_p = NULL;
1759 	int cmdsn_ret = 0;
1760 	/*
1761 	 * Initiator is expecting a NopIN ping reply..
1762 	 */
1763 	if (hdr->itt != RESERVED_ITT) {
1764 		if (!cmd)
1765 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1766 						(unsigned char *)hdr);
1767 
1768 		spin_lock_bh(&conn->cmd_lock);
1769 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1770 		spin_unlock_bh(&conn->cmd_lock);
1771 
1772 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1773 
1774 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1775 			iscsit_add_cmd_to_response_queue(cmd, conn,
1776 							 cmd->i_state);
1777 			return 0;
1778 		}
1779 
1780 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1781 				(unsigned char *)hdr, hdr->cmdsn);
1782                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1783 			return 0;
1784 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1785 			return -1;
1786 
1787 		return 0;
1788 	}
1789 	/*
1790 	 * This was a response to a unsolicited NOPIN ping.
1791 	 */
1792 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1793 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1794 		if (!cmd_p)
1795 			return -EINVAL;
1796 
1797 		iscsit_stop_nopin_response_timer(conn);
1798 
1799 		cmd_p->i_state = ISTATE_REMOVE;
1800 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1801 
1802 		iscsit_start_nopin_timer(conn);
1803 		return 0;
1804 	}
1805 	/*
1806 	 * Otherwise, initiator is not expecting a NOPIN is response.
1807 	 * Just ignore for now.
1808 	 */
1809 
1810 	if (cmd)
1811 		iscsit_free_cmd(cmd, false);
1812 
1813         return 0;
1814 }
1815 EXPORT_SYMBOL(iscsit_process_nop_out);
1816 
1817 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1818 				 unsigned char *buf)
1819 {
1820 	unsigned char *ping_data = NULL;
1821 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1822 	struct kvec *iov = NULL;
1823 	u32 payload_length = ntoh24(hdr->dlength);
1824 	int ret;
1825 
1826 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1827 	if (ret < 0)
1828 		return 0;
1829 	/*
1830 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1831 	 */
1832 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1833 		u32 checksum, data_crc, padding = 0;
1834 		int niov = 0, rx_got, rx_size = payload_length;
1835 
1836 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1837 		if (!ping_data) {
1838 			pr_err("Unable to allocate memory for"
1839 				" NOPOUT ping data.\n");
1840 			ret = -1;
1841 			goto out;
1842 		}
1843 
1844 		iov = &cmd->iov_misc[0];
1845 		iov[niov].iov_base	= ping_data;
1846 		iov[niov++].iov_len	= payload_length;
1847 
1848 		padding = ((-payload_length) & 3);
1849 		if (padding != 0) {
1850 			pr_debug("Receiving %u additional bytes"
1851 				" for padding.\n", padding);
1852 			iov[niov].iov_base	= &cmd->pad_bytes;
1853 			iov[niov++].iov_len	= padding;
1854 			rx_size += padding;
1855 		}
1856 		if (conn->conn_ops->DataDigest) {
1857 			iov[niov].iov_base	= &checksum;
1858 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1859 			rx_size += ISCSI_CRC_LEN;
1860 		}
1861 
1862 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1863 		if (rx_got != rx_size) {
1864 			ret = -1;
1865 			goto out;
1866 		}
1867 
1868 		if (conn->conn_ops->DataDigest) {
1869 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
1870 					ping_data, payload_length,
1871 					padding, cmd->pad_bytes,
1872 					(u8 *)&data_crc);
1873 
1874 			if (checksum != data_crc) {
1875 				pr_err("Ping data CRC32C DataDigest"
1876 				" 0x%08x does not match computed 0x%08x\n",
1877 					checksum, data_crc);
1878 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1879 					pr_err("Unable to recover from"
1880 					" NOPOUT Ping DataCRC failure while in"
1881 						" ERL=0.\n");
1882 					ret = -1;
1883 					goto out;
1884 				} else {
1885 					/*
1886 					 * Silently drop this PDU and let the
1887 					 * initiator plug the CmdSN gap.
1888 					 */
1889 					pr_debug("Dropping NOPOUT"
1890 					" Command CmdSN: 0x%08x due to"
1891 					" DataCRC error.\n", hdr->cmdsn);
1892 					ret = 0;
1893 					goto out;
1894 				}
1895 			} else {
1896 				pr_debug("Got CRC32C DataDigest"
1897 				" 0x%08x for %u bytes of ping data.\n",
1898 					checksum, payload_length);
1899 			}
1900 		}
1901 
1902 		ping_data[payload_length] = '\0';
1903 		/*
1904 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1905 		 */
1906 		cmd->buf_ptr = ping_data;
1907 		cmd->buf_ptr_size = payload_length;
1908 
1909 		pr_debug("Got %u bytes of NOPOUT ping"
1910 			" data.\n", payload_length);
1911 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1912 	}
1913 
1914 	return iscsit_process_nop_out(conn, cmd, hdr);
1915 out:
1916 	if (cmd)
1917 		iscsit_free_cmd(cmd, false);
1918 
1919 	kfree(ping_data);
1920 	return ret;
1921 }
1922 
1923 int
1924 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1925 			   unsigned char *buf)
1926 {
1927 	struct se_tmr_req *se_tmr;
1928 	struct iscsi_tmr_req *tmr_req;
1929 	struct iscsi_tm *hdr;
1930 	int out_of_order_cmdsn = 0, ret;
1931 	bool sess_ref = false;
1932 	u8 function;
1933 
1934 	hdr			= (struct iscsi_tm *) buf;
1935 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1936 	function = hdr->flags;
1937 
1938 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1939 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1940 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1941 		hdr->rtt, hdr->refcmdsn, conn->cid);
1942 
1943 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1944 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1945 	     hdr->rtt != RESERVED_ITT)) {
1946 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1947 		hdr->rtt = RESERVED_ITT;
1948 	}
1949 
1950 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1951 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1952 		pr_err("Task Management Request TASK_REASSIGN not"
1953 			" issued as immediate command, bad iSCSI Initiator"
1954 				"implementation\n");
1955 		return iscsit_add_reject_cmd(cmd,
1956 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1957 	}
1958 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1959 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1960 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1961 
1962 	cmd->data_direction = DMA_NONE;
1963 
1964 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
1965 	if (!cmd->tmr_req) {
1966 		pr_err("Unable to allocate memory for"
1967 			" Task Management command!\n");
1968 		return iscsit_add_reject_cmd(cmd,
1969 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1970 					     buf);
1971 	}
1972 
1973 	/*
1974 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
1975 	 * LIO-Target $FABRIC_MOD
1976 	 */
1977 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
1978 
1979 		u8 tcm_function;
1980 		int ret;
1981 
1982 		transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1983 				      conn->sess->se_sess, 0, DMA_NONE,
1984 				      TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
1985 
1986 		target_get_sess_cmd(&cmd->se_cmd, true);
1987 		sess_ref = true;
1988 
1989 		switch (function) {
1990 		case ISCSI_TM_FUNC_ABORT_TASK:
1991 			tcm_function = TMR_ABORT_TASK;
1992 			break;
1993 		case ISCSI_TM_FUNC_ABORT_TASK_SET:
1994 			tcm_function = TMR_ABORT_TASK_SET;
1995 			break;
1996 		case ISCSI_TM_FUNC_CLEAR_ACA:
1997 			tcm_function = TMR_CLEAR_ACA;
1998 			break;
1999 		case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2000 			tcm_function = TMR_CLEAR_TASK_SET;
2001 			break;
2002 		case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2003 			tcm_function = TMR_LUN_RESET;
2004 			break;
2005 		case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2006 			tcm_function = TMR_TARGET_WARM_RESET;
2007 			break;
2008 		case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2009 			tcm_function = TMR_TARGET_COLD_RESET;
2010 			break;
2011 		default:
2012 			pr_err("Unknown iSCSI TMR Function:"
2013 			       " 0x%02x\n", function);
2014 			return iscsit_add_reject_cmd(cmd,
2015 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2016 		}
2017 
2018 		ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req,
2019 					 tcm_function, GFP_KERNEL);
2020 		if (ret < 0)
2021 			return iscsit_add_reject_cmd(cmd,
2022 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2023 
2024 		cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2025 	}
2026 
2027 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2028 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2029 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2030 	cmd->init_task_tag	= hdr->itt;
2031 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2032 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2033 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2034 	se_tmr			= cmd->se_cmd.se_tmr_req;
2035 	tmr_req			= cmd->tmr_req;
2036 	/*
2037 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2038 	 */
2039 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2040 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
2041 					       scsilun_to_int(&hdr->lun));
2042 		if (ret < 0) {
2043 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2044 			goto attach;
2045 		}
2046 	}
2047 
2048 	switch (function) {
2049 	case ISCSI_TM_FUNC_ABORT_TASK:
2050 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2051 		if (se_tmr->response)
2052 			goto attach;
2053 		break;
2054 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2055 	case ISCSI_TM_FUNC_CLEAR_ACA:
2056 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2057 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2058 		break;
2059 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2060 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2061 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2062 			goto attach;
2063 		}
2064 		break;
2065 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2066 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2067 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2068 			goto attach;
2069 		}
2070 		break;
2071 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2072 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2073 		/*
2074 		 * Perform sanity checks on the ExpDataSN only if the
2075 		 * TASK_REASSIGN was successful.
2076 		 */
2077 		if (se_tmr->response)
2078 			break;
2079 
2080 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2081 			return iscsit_add_reject_cmd(cmd,
2082 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2083 		break;
2084 	default:
2085 		pr_err("Unknown TMR function: 0x%02x, protocol"
2086 			" error.\n", function);
2087 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2088 		goto attach;
2089 	}
2090 
2091 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2092 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2093 		se_tmr->call_transport = 1;
2094 attach:
2095 	spin_lock_bh(&conn->cmd_lock);
2096 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2097 	spin_unlock_bh(&conn->cmd_lock);
2098 
2099 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2100 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2101 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
2102 			out_of_order_cmdsn = 1;
2103 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2104 			return 0;
2105 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2106 			return -1;
2107 	}
2108 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2109 
2110 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2111 		return 0;
2112 	/*
2113 	 * Found the referenced task, send to transport for processing.
2114 	 */
2115 	if (se_tmr->call_transport)
2116 		return transport_generic_handle_tmr(&cmd->se_cmd);
2117 
2118 	/*
2119 	 * Could not find the referenced LUN, task, or Task Management
2120 	 * command not authorized or supported.  Change state and
2121 	 * let the tx_thread send the response.
2122 	 *
2123 	 * For connection recovery, this is also the default action for
2124 	 * TMR TASK_REASSIGN.
2125 	 */
2126 	if (sess_ref) {
2127 		pr_debug("Handle TMR, using sess_ref=true check\n");
2128 		target_put_sess_cmd(&cmd->se_cmd);
2129 	}
2130 
2131 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2132 	return 0;
2133 }
2134 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2135 
2136 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2137 int
2138 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2139 		      struct iscsi_text *hdr)
2140 {
2141 	u32 payload_length = ntoh24(hdr->dlength);
2142 
2143 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2144 		pr_err("Unable to accept text parameter length: %u"
2145 			"greater than MaxXmitDataSegmentLength %u.\n",
2146 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2147 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2148 					 (unsigned char *)hdr);
2149 	}
2150 
2151 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2152 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2153 		pr_err("Multi sequence text commands currently not supported\n");
2154 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2155 					(unsigned char *)hdr);
2156 	}
2157 
2158 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2159 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2160 		hdr->exp_statsn, payload_length);
2161 
2162 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2163 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2164 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2165 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2166 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2167 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2168 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2169 	cmd->data_direction	= DMA_NONE;
2170 	cmd->text_in_ptr	= NULL;
2171 
2172 	return 0;
2173 }
2174 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2175 
2176 int
2177 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2178 			struct iscsi_text *hdr)
2179 {
2180 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2181 	int cmdsn_ret;
2182 
2183 	if (!text_in) {
2184 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2185 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2186 			pr_err("Unable to locate text_in buffer for sendtargets"
2187 			       " discovery\n");
2188 			goto reject;
2189 		}
2190 		goto empty_sendtargets;
2191 	}
2192 	if (strncmp("SendTargets", text_in, 11) != 0) {
2193 		pr_err("Received Text Data that is not"
2194 			" SendTargets, cannot continue.\n");
2195 		goto reject;
2196 	}
2197 	text_ptr = strchr(text_in, '=');
2198 	if (!text_ptr) {
2199 		pr_err("No \"=\" separator found in Text Data,"
2200 			"  cannot continue.\n");
2201 		goto reject;
2202 	}
2203 	if (!strncmp("=All", text_ptr, 4)) {
2204 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2205 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2206 		   !strncmp("=eui.", text_ptr, 5)) {
2207 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2208 	} else {
2209 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2210 		goto reject;
2211 	}
2212 
2213 	spin_lock_bh(&conn->cmd_lock);
2214 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2215 	spin_unlock_bh(&conn->cmd_lock);
2216 
2217 empty_sendtargets:
2218 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2219 
2220 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2221 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2222 				(unsigned char *)hdr, hdr->cmdsn);
2223 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2224 			return -1;
2225 
2226 		return 0;
2227 	}
2228 
2229 	return iscsit_execute_cmd(cmd, 0);
2230 
2231 reject:
2232 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2233 				 (unsigned char *)hdr);
2234 }
2235 EXPORT_SYMBOL(iscsit_process_text_cmd);
2236 
2237 static int
2238 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2239 		       unsigned char *buf)
2240 {
2241 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2242 	char *text_in = NULL;
2243 	u32 payload_length = ntoh24(hdr->dlength);
2244 	int rx_size, rc;
2245 
2246 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2247 	if (rc < 0)
2248 		return 0;
2249 
2250 	rx_size = payload_length;
2251 	if (payload_length) {
2252 		u32 checksum = 0, data_crc = 0;
2253 		u32 padding = 0, pad_bytes = 0;
2254 		int niov = 0, rx_got;
2255 		struct kvec iov[3];
2256 
2257 		text_in = kzalloc(payload_length, GFP_KERNEL);
2258 		if (!text_in) {
2259 			pr_err("Unable to allocate memory for"
2260 				" incoming text parameters\n");
2261 			goto reject;
2262 		}
2263 		cmd->text_in_ptr = text_in;
2264 
2265 		memset(iov, 0, 3 * sizeof(struct kvec));
2266 		iov[niov].iov_base	= text_in;
2267 		iov[niov++].iov_len	= payload_length;
2268 
2269 		padding = ((-payload_length) & 3);
2270 		if (padding != 0) {
2271 			iov[niov].iov_base = &pad_bytes;
2272 			iov[niov++].iov_len  = padding;
2273 			rx_size += padding;
2274 			pr_debug("Receiving %u additional bytes"
2275 					" for padding.\n", padding);
2276 		}
2277 		if (conn->conn_ops->DataDigest) {
2278 			iov[niov].iov_base	= &checksum;
2279 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2280 			rx_size += ISCSI_CRC_LEN;
2281 		}
2282 
2283 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2284 		if (rx_got != rx_size)
2285 			goto reject;
2286 
2287 		if (conn->conn_ops->DataDigest) {
2288 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2289 					text_in, payload_length,
2290 					padding, (u8 *)&pad_bytes,
2291 					(u8 *)&data_crc);
2292 
2293 			if (checksum != data_crc) {
2294 				pr_err("Text data CRC32C DataDigest"
2295 					" 0x%08x does not match computed"
2296 					" 0x%08x\n", checksum, data_crc);
2297 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2298 					pr_err("Unable to recover from"
2299 					" Text Data digest failure while in"
2300 						" ERL=0.\n");
2301 					goto reject;
2302 				} else {
2303 					/*
2304 					 * Silently drop this PDU and let the
2305 					 * initiator plug the CmdSN gap.
2306 					 */
2307 					pr_debug("Dropping Text"
2308 					" Command CmdSN: 0x%08x due to"
2309 					" DataCRC error.\n", hdr->cmdsn);
2310 					kfree(text_in);
2311 					return 0;
2312 				}
2313 			} else {
2314 				pr_debug("Got CRC32C DataDigest"
2315 					" 0x%08x for %u bytes of text data.\n",
2316 						checksum, payload_length);
2317 			}
2318 		}
2319 		text_in[payload_length - 1] = '\0';
2320 		pr_debug("Successfully read %d bytes of text"
2321 				" data.\n", payload_length);
2322 	}
2323 
2324 	return iscsit_process_text_cmd(conn, cmd, hdr);
2325 
2326 reject:
2327 	kfree(cmd->text_in_ptr);
2328 	cmd->text_in_ptr = NULL;
2329 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2330 }
2331 
2332 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2333 {
2334 	struct iscsi_conn *conn_p;
2335 	struct iscsi_session *sess = conn->sess;
2336 
2337 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2338 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2339 
2340 	atomic_set(&sess->session_logout, 1);
2341 	atomic_set(&conn->conn_logout_remove, 1);
2342 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2343 
2344 	iscsit_inc_conn_usage_count(conn);
2345 	iscsit_inc_session_usage_count(sess);
2346 
2347 	spin_lock_bh(&sess->conn_lock);
2348 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2349 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2350 			continue;
2351 
2352 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2353 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2354 	}
2355 	spin_unlock_bh(&sess->conn_lock);
2356 
2357 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2358 
2359 	return 0;
2360 }
2361 
2362 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2363 {
2364 	struct iscsi_conn *l_conn;
2365 	struct iscsi_session *sess = conn->sess;
2366 
2367 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2368 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2369 
2370 	/*
2371 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2372 	 * can arrive on a connection with a differing CID.
2373 	 */
2374 	if (conn->cid == cmd->logout_cid) {
2375 		spin_lock_bh(&conn->state_lock);
2376 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2377 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2378 
2379 		atomic_set(&conn->conn_logout_remove, 1);
2380 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2381 		iscsit_inc_conn_usage_count(conn);
2382 
2383 		spin_unlock_bh(&conn->state_lock);
2384 	} else {
2385 		/*
2386 		 * Handle all different cid CLOSECONNECTION requests in
2387 		 * iscsit_logout_post_handler_diffcid() as to give enough
2388 		 * time for any non immediate command's CmdSN to be
2389 		 * acknowledged on the connection in question.
2390 		 *
2391 		 * Here we simply make sure the CID is still around.
2392 		 */
2393 		l_conn = iscsit_get_conn_from_cid(sess,
2394 				cmd->logout_cid);
2395 		if (!l_conn) {
2396 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2397 			iscsit_add_cmd_to_response_queue(cmd, conn,
2398 					cmd->i_state);
2399 			return 0;
2400 		}
2401 
2402 		iscsit_dec_conn_usage_count(l_conn);
2403 	}
2404 
2405 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2406 
2407 	return 0;
2408 }
2409 
2410 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2411 {
2412 	struct iscsi_session *sess = conn->sess;
2413 
2414 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2415 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2416 
2417 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2418 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2419 			" while ERL!=2.\n");
2420 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2421 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2422 		return 0;
2423 	}
2424 
2425 	if (conn->cid == cmd->logout_cid) {
2426 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2427 			" with CID: %hu on CID: %hu, implementation error.\n",
2428 				cmd->logout_cid, conn->cid);
2429 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2430 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2431 		return 0;
2432 	}
2433 
2434 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2435 
2436 	return 0;
2437 }
2438 
2439 int
2440 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2441 			unsigned char *buf)
2442 {
2443 	int cmdsn_ret, logout_remove = 0;
2444 	u8 reason_code = 0;
2445 	struct iscsi_logout *hdr;
2446 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2447 
2448 	hdr			= (struct iscsi_logout *) buf;
2449 	reason_code		= (hdr->flags & 0x7f);
2450 
2451 	if (tiqn) {
2452 		spin_lock(&tiqn->logout_stats.lock);
2453 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2454 			tiqn->logout_stats.normal_logouts++;
2455 		else
2456 			tiqn->logout_stats.abnormal_logouts++;
2457 		spin_unlock(&tiqn->logout_stats.lock);
2458 	}
2459 
2460 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2461 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2462 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2463 		hdr->cid, conn->cid);
2464 
2465 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2466 		pr_err("Received logout request on connection that"
2467 			" is not in logged in state, ignoring request.\n");
2468 		iscsit_free_cmd(cmd, false);
2469 		return 0;
2470 	}
2471 
2472 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2473 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2474 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2475 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2476 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2477 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2478 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2479 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2480 	cmd->logout_reason      = reason_code;
2481 	cmd->data_direction     = DMA_NONE;
2482 
2483 	/*
2484 	 * We need to sleep in these cases (by returning 1) until the Logout
2485 	 * Response gets sent in the tx thread.
2486 	 */
2487 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2488 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2489 	    be16_to_cpu(hdr->cid) == conn->cid))
2490 		logout_remove = 1;
2491 
2492 	spin_lock_bh(&conn->cmd_lock);
2493 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2494 	spin_unlock_bh(&conn->cmd_lock);
2495 
2496 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2497 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2498 
2499 	/*
2500 	 * Immediate commands are executed, well, immediately.
2501 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2502 	 */
2503 	if (cmd->immediate_cmd) {
2504 		int ret = iscsit_execute_cmd(cmd, 0);
2505 
2506 		if (ret < 0)
2507 			return ret;
2508 	} else {
2509 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2510 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2511 			logout_remove = 0;
2512 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2513 			return -1;
2514 	}
2515 
2516 	return logout_remove;
2517 }
2518 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2519 
2520 int iscsit_handle_snack(
2521 	struct iscsi_conn *conn,
2522 	unsigned char *buf)
2523 {
2524 	struct iscsi_snack *hdr;
2525 
2526 	hdr			= (struct iscsi_snack *) buf;
2527 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2528 
2529 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2530 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2531 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2532 			hdr->begrun, hdr->runlength, conn->cid);
2533 
2534 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2535 		pr_err("Initiator sent SNACK request while in"
2536 			" ErrorRecoveryLevel=0.\n");
2537 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2538 					 buf);
2539 	}
2540 	/*
2541 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2542 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2543 	 */
2544 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2545 	case 0:
2546 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2547 			hdr->itt,
2548 			be32_to_cpu(hdr->ttt),
2549 			be32_to_cpu(hdr->begrun),
2550 			be32_to_cpu(hdr->runlength));
2551 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2552 		return iscsit_handle_status_snack(conn, hdr->itt,
2553 			be32_to_cpu(hdr->ttt),
2554 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2555 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2556 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2557 			be32_to_cpu(hdr->begrun),
2558 			be32_to_cpu(hdr->runlength));
2559 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2560 		/* FIXME: Support R-Data SNACK */
2561 		pr_err("R-Data SNACK Not Supported.\n");
2562 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2563 					 buf);
2564 	default:
2565 		pr_err("Unknown SNACK type 0x%02x, protocol"
2566 			" error.\n", hdr->flags & 0x0f);
2567 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2568 					 buf);
2569 	}
2570 
2571 	return 0;
2572 }
2573 EXPORT_SYMBOL(iscsit_handle_snack);
2574 
2575 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2576 {
2577 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2578 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2579 		wait_for_completion_interruptible_timeout(
2580 					&conn->rx_half_close_comp,
2581 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2582 	}
2583 }
2584 
2585 static int iscsit_handle_immediate_data(
2586 	struct iscsi_cmd *cmd,
2587 	struct iscsi_scsi_req *hdr,
2588 	u32 length)
2589 {
2590 	int iov_ret, rx_got = 0, rx_size = 0;
2591 	u32 checksum, iov_count = 0, padding = 0;
2592 	struct iscsi_conn *conn = cmd->conn;
2593 	struct kvec *iov;
2594 
2595 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2596 	if (iov_ret < 0)
2597 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2598 
2599 	rx_size = length;
2600 	iov_count = iov_ret;
2601 	iov = &cmd->iov_data[0];
2602 
2603 	padding = ((-length) & 3);
2604 	if (padding != 0) {
2605 		iov[iov_count].iov_base	= cmd->pad_bytes;
2606 		iov[iov_count++].iov_len = padding;
2607 		rx_size += padding;
2608 	}
2609 
2610 	if (conn->conn_ops->DataDigest) {
2611 		iov[iov_count].iov_base		= &checksum;
2612 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2613 		rx_size += ISCSI_CRC_LEN;
2614 	}
2615 
2616 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2617 
2618 	iscsit_unmap_iovec(cmd);
2619 
2620 	if (rx_got != rx_size) {
2621 		iscsit_rx_thread_wait_for_tcp(conn);
2622 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2623 	}
2624 
2625 	if (conn->conn_ops->DataDigest) {
2626 		u32 data_crc;
2627 
2628 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2629 						    cmd->write_data_done, length, padding,
2630 						    cmd->pad_bytes);
2631 
2632 		if (checksum != data_crc) {
2633 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2634 				" does not match computed 0x%08x\n", checksum,
2635 				data_crc);
2636 
2637 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2638 				pr_err("Unable to recover from"
2639 					" Immediate Data digest failure while"
2640 					" in ERL=0.\n");
2641 				iscsit_reject_cmd(cmd,
2642 						ISCSI_REASON_DATA_DIGEST_ERROR,
2643 						(unsigned char *)hdr);
2644 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2645 			} else {
2646 				iscsit_reject_cmd(cmd,
2647 						ISCSI_REASON_DATA_DIGEST_ERROR,
2648 						(unsigned char *)hdr);
2649 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2650 			}
2651 		} else {
2652 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2653 				" %u bytes of Immediate Data\n", checksum,
2654 				length);
2655 		}
2656 	}
2657 
2658 	cmd->write_data_done += length;
2659 
2660 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2661 		spin_lock_bh(&cmd->istate_lock);
2662 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2663 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2664 		spin_unlock_bh(&cmd->istate_lock);
2665 	}
2666 
2667 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2668 }
2669 
2670 /*
2671  *	Called with sess->conn_lock held.
2672  */
2673 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2674 	with active network interface */
2675 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2676 {
2677 	struct iscsi_cmd *cmd;
2678 	struct iscsi_conn *conn_p;
2679 	bool found = false;
2680 
2681 	/*
2682 	 * Only send a Asynchronous Message on connections whos network
2683 	 * interface is still functional.
2684 	 */
2685 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2686 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2687 			iscsit_inc_conn_usage_count(conn_p);
2688 			found = true;
2689 			break;
2690 		}
2691 	}
2692 
2693 	if (!found)
2694 		return;
2695 
2696 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2697 	if (!cmd) {
2698 		iscsit_dec_conn_usage_count(conn_p);
2699 		return;
2700 	}
2701 
2702 	cmd->logout_cid = conn->cid;
2703 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2704 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2705 
2706 	spin_lock_bh(&conn_p->cmd_lock);
2707 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2708 	spin_unlock_bh(&conn_p->cmd_lock);
2709 
2710 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2711 	iscsit_dec_conn_usage_count(conn_p);
2712 }
2713 
2714 static int iscsit_send_conn_drop_async_message(
2715 	struct iscsi_cmd *cmd,
2716 	struct iscsi_conn *conn)
2717 {
2718 	struct iscsi_async *hdr;
2719 
2720 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2721 
2722 	hdr			= (struct iscsi_async *) cmd->pdu;
2723 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2724 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2725 	cmd->init_task_tag	= RESERVED_ITT;
2726 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2727 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2728 	cmd->stat_sn		= conn->stat_sn++;
2729 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2730 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2731 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2732 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2733 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2734 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2735 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2736 
2737 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2738 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2739 			cmd->logout_cid, conn->cid);
2740 
2741 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2742 }
2743 
2744 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2745 {
2746 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2747 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2748 		wait_for_completion_interruptible_timeout(
2749 					&conn->tx_half_close_comp,
2750 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2751 	}
2752 }
2753 
2754 void
2755 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2756 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2757 			bool set_statsn)
2758 {
2759 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2760 	hdr->flags		= datain->flags;
2761 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2762 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2763 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2764 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2765 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2766 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2767 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2768 		}
2769 	}
2770 	hton24(hdr->dlength, datain->length);
2771 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2772 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2773 				(struct scsi_lun *)&hdr->lun);
2774 	else
2775 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2776 
2777 	hdr->itt		= cmd->init_task_tag;
2778 
2779 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2780 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2781 	else
2782 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2783 	if (set_statsn)
2784 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2785 	else
2786 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2787 
2788 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2789 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2790 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2791 	hdr->offset		= cpu_to_be32(datain->offset);
2792 
2793 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2794 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2795 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2796 		ntohl(hdr->offset), datain->length, conn->cid);
2797 }
2798 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2799 
2800 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2801 {
2802 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2803 	struct iscsi_datain datain;
2804 	struct iscsi_datain_req *dr;
2805 	int eodr = 0, ret;
2806 	bool set_statsn = false;
2807 
2808 	memset(&datain, 0, sizeof(struct iscsi_datain));
2809 	dr = iscsit_get_datain_values(cmd, &datain);
2810 	if (!dr) {
2811 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2812 				cmd->init_task_tag);
2813 		return -1;
2814 	}
2815 	/*
2816 	 * Be paranoid and double check the logic for now.
2817 	 */
2818 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2819 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2820 			" datain.length: %u exceeds cmd->data_length: %u\n",
2821 			cmd->init_task_tag, datain.offset, datain.length,
2822 			cmd->se_cmd.data_length);
2823 		return -1;
2824 	}
2825 
2826 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2827 	/*
2828 	 * Special case for successfully execution w/ both DATAIN
2829 	 * and Sense Data.
2830 	 */
2831 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2832 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2833 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2834 	else {
2835 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2836 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2837 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2838 			cmd->stat_sn = conn->stat_sn++;
2839 			set_statsn = true;
2840 		} else if (dr->dr_complete ==
2841 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2842 			set_statsn = true;
2843 	}
2844 
2845 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2846 
2847 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2848 	if (ret < 0)
2849 		return ret;
2850 
2851 	if (dr->dr_complete) {
2852 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2853 				2 : 1;
2854 		iscsit_free_datain_req(cmd, dr);
2855 	}
2856 
2857 	return eodr;
2858 }
2859 
2860 int
2861 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2862 			struct iscsi_logout_rsp *hdr)
2863 {
2864 	struct iscsi_conn *logout_conn = NULL;
2865 	struct iscsi_conn_recovery *cr = NULL;
2866 	struct iscsi_session *sess = conn->sess;
2867 	/*
2868 	 * The actual shutting down of Sessions and/or Connections
2869 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2870 	 * is done in scsi_logout_post_handler().
2871 	 */
2872 	switch (cmd->logout_reason) {
2873 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2874 		pr_debug("iSCSI session logout successful, setting"
2875 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2876 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2877 		break;
2878 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2879 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2880 			break;
2881 		/*
2882 		 * For CLOSECONNECTION logout requests carrying
2883 		 * a matching logout CID -> local CID, the reference
2884 		 * for the local CID will have been incremented in
2885 		 * iscsi_logout_closeconnection().
2886 		 *
2887 		 * For CLOSECONNECTION logout requests carrying
2888 		 * a different CID than the connection it arrived
2889 		 * on, the connection responding to cmd->logout_cid
2890 		 * is stopped in iscsit_logout_post_handler_diffcid().
2891 		 */
2892 
2893 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2894 			" successful.\n", cmd->logout_cid, conn->cid);
2895 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2896 		break;
2897 	case ISCSI_LOGOUT_REASON_RECOVERY:
2898 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2899 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2900 			break;
2901 		/*
2902 		 * If the connection is still active from our point of view
2903 		 * force connection recovery to occur.
2904 		 */
2905 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2906 				cmd->logout_cid);
2907 		if (logout_conn) {
2908 			iscsit_connection_reinstatement_rcfr(logout_conn);
2909 			iscsit_dec_conn_usage_count(logout_conn);
2910 		}
2911 
2912 		cr = iscsit_get_inactive_connection_recovery_entry(
2913 				conn->sess, cmd->logout_cid);
2914 		if (!cr) {
2915 			pr_err("Unable to locate CID: %hu for"
2916 			" REMOVECONNFORRECOVERY Logout Request.\n",
2917 				cmd->logout_cid);
2918 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2919 			break;
2920 		}
2921 
2922 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2923 
2924 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2925 			" for recovery for CID: %hu on CID: %hu successful.\n",
2926 				cmd->logout_cid, conn->cid);
2927 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2928 		break;
2929 	default:
2930 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2931 				cmd->logout_reason);
2932 		return -1;
2933 	}
2934 
2935 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2936 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2937 	hdr->response		= cmd->logout_response;
2938 	hdr->itt		= cmd->init_task_tag;
2939 	cmd->stat_sn		= conn->stat_sn++;
2940 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2941 
2942 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2943 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2944 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2945 
2946 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2947 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2948 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2949 		cmd->logout_cid, conn->cid);
2950 
2951 	return 0;
2952 }
2953 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2954 
2955 static int
2956 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2957 {
2958 	int rc;
2959 
2960 	rc = iscsit_build_logout_rsp(cmd, conn,
2961 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2962 	if (rc < 0)
2963 		return rc;
2964 
2965 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2966 }
2967 
2968 void
2969 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2970 		       struct iscsi_nopin *hdr, bool nopout_response)
2971 {
2972 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2973 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2974         hton24(hdr->dlength, cmd->buf_ptr_size);
2975 	if (nopout_response)
2976 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2977 	hdr->itt		= cmd->init_task_tag;
2978 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2979 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2980 				  conn->stat_sn;
2981 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2982 
2983 	if (nopout_response)
2984 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2985 
2986 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2987 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2988 
2989 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
2990 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
2991 		"Solicited" : "Unsolicited", cmd->init_task_tag,
2992 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
2993 }
2994 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
2995 
2996 /*
2997  *	Unsolicited NOPIN, either requesting a response or not.
2998  */
2999 static int iscsit_send_unsolicited_nopin(
3000 	struct iscsi_cmd *cmd,
3001 	struct iscsi_conn *conn,
3002 	int want_response)
3003 {
3004 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3005 	int ret;
3006 
3007 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3008 
3009 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3010 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3011 
3012 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3013 	if (ret < 0)
3014 		return ret;
3015 
3016 	spin_lock_bh(&cmd->istate_lock);
3017 	cmd->i_state = want_response ?
3018 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3019 	spin_unlock_bh(&cmd->istate_lock);
3020 
3021 	return 0;
3022 }
3023 
3024 static int
3025 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3026 {
3027 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3028 
3029 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3030 
3031 	/*
3032 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
3033 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
3034 	 */
3035 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3036 
3037 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3038 						     cmd->buf_ptr,
3039 						     cmd->buf_ptr_size);
3040 }
3041 
3042 static int iscsit_send_r2t(
3043 	struct iscsi_cmd *cmd,
3044 	struct iscsi_conn *conn)
3045 {
3046 	struct iscsi_r2t *r2t;
3047 	struct iscsi_r2t_rsp *hdr;
3048 	int ret;
3049 
3050 	r2t = iscsit_get_r2t_from_list(cmd);
3051 	if (!r2t)
3052 		return -1;
3053 
3054 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3055 	memset(hdr, 0, ISCSI_HDR_LEN);
3056 	hdr->opcode		= ISCSI_OP_R2T;
3057 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3058 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3059 			(struct scsi_lun *)&hdr->lun);
3060 	hdr->itt		= cmd->init_task_tag;
3061 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3062 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3063 	else
3064 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3065 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3066 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3067 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3068 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3069 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3070 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3071 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3072 
3073 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3074 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3075 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3076 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3077 			r2t->offset, r2t->xfer_len, conn->cid);
3078 
3079 	spin_lock_bh(&cmd->r2t_lock);
3080 	r2t->sent_r2t = 1;
3081 	spin_unlock_bh(&cmd->r2t_lock);
3082 
3083 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3084 	if (ret < 0) {
3085 		return ret;
3086 	}
3087 
3088 	spin_lock_bh(&cmd->dataout_timeout_lock);
3089 	iscsit_start_dataout_timer(cmd, conn);
3090 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3091 
3092 	return 0;
3093 }
3094 
3095 /*
3096  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3097  *		connection recovery.
3098  */
3099 int iscsit_build_r2ts_for_cmd(
3100 	struct iscsi_conn *conn,
3101 	struct iscsi_cmd *cmd,
3102 	bool recovery)
3103 {
3104 	int first_r2t = 1;
3105 	u32 offset = 0, xfer_len = 0;
3106 
3107 	spin_lock_bh(&cmd->r2t_lock);
3108 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3109 		spin_unlock_bh(&cmd->r2t_lock);
3110 		return 0;
3111 	}
3112 
3113 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3114 	    !recovery)
3115 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3116 
3117 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3118 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3119 			offset = cmd->r2t_offset;
3120 
3121 			if (first_r2t && recovery) {
3122 				int new_data_end = offset +
3123 					conn->sess->sess_ops->MaxBurstLength -
3124 					cmd->next_burst_len;
3125 
3126 				if (new_data_end > cmd->se_cmd.data_length)
3127 					xfer_len = cmd->se_cmd.data_length - offset;
3128 				else
3129 					xfer_len =
3130 						conn->sess->sess_ops->MaxBurstLength -
3131 						cmd->next_burst_len;
3132 			} else {
3133 				int new_data_end = offset +
3134 					conn->sess->sess_ops->MaxBurstLength;
3135 
3136 				if (new_data_end > cmd->se_cmd.data_length)
3137 					xfer_len = cmd->se_cmd.data_length - offset;
3138 				else
3139 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3140 			}
3141 			cmd->r2t_offset += xfer_len;
3142 
3143 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3144 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3145 		} else {
3146 			struct iscsi_seq *seq;
3147 
3148 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3149 			if (!seq) {
3150 				spin_unlock_bh(&cmd->r2t_lock);
3151 				return -1;
3152 			}
3153 
3154 			offset = seq->offset;
3155 			xfer_len = seq->xfer_len;
3156 
3157 			if (cmd->seq_send_order == cmd->seq_count)
3158 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3159 		}
3160 		cmd->outstanding_r2ts++;
3161 		first_r2t = 0;
3162 
3163 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3164 			spin_unlock_bh(&cmd->r2t_lock);
3165 			return -1;
3166 		}
3167 
3168 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3169 			break;
3170 	}
3171 	spin_unlock_bh(&cmd->r2t_lock);
3172 
3173 	return 0;
3174 }
3175 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3176 
3177 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3178 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3179 {
3180 	if (inc_stat_sn)
3181 		cmd->stat_sn = conn->stat_sn++;
3182 
3183 	atomic_long_inc(&conn->sess->rsp_pdus);
3184 
3185 	memset(hdr, 0, ISCSI_HDR_LEN);
3186 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3187 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3188 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3189 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3190 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3191 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3192 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3193 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3194 	}
3195 	hdr->response		= cmd->iscsi_response;
3196 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3197 	hdr->itt		= cmd->init_task_tag;
3198 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3199 
3200 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3201 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3202 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3203 
3204 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3205 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3206 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3207 		cmd->se_cmd.scsi_status, conn->cid);
3208 }
3209 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3210 
3211 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3212 {
3213 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3214 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3215 	void *data_buf = NULL;
3216 	u32 padding = 0, data_buf_len = 0;
3217 
3218 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3219 
3220 	/*
3221 	 * Attach SENSE DATA payload to iSCSI Response PDU
3222 	 */
3223 	if (cmd->se_cmd.sense_buffer &&
3224 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3225 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3226 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3227 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3228 
3229 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3230 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3231 		data_buf = cmd->sense_buffer;
3232 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3233 
3234 		if (padding) {
3235 			memset(cmd->sense_buffer +
3236 				cmd->se_cmd.scsi_sense_length, 0, padding);
3237 			pr_debug("Adding %u bytes of padding to"
3238 				" SENSE.\n", padding);
3239 		}
3240 
3241 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3242 				" Response PDU\n",
3243 				cmd->se_cmd.scsi_sense_length);
3244 	}
3245 
3246 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3247 						     data_buf_len);
3248 }
3249 
3250 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3251 {
3252 	switch (se_tmr->response) {
3253 	case TMR_FUNCTION_COMPLETE:
3254 		return ISCSI_TMF_RSP_COMPLETE;
3255 	case TMR_TASK_DOES_NOT_EXIST:
3256 		return ISCSI_TMF_RSP_NO_TASK;
3257 	case TMR_LUN_DOES_NOT_EXIST:
3258 		return ISCSI_TMF_RSP_NO_LUN;
3259 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3260 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3261 	case TMR_FUNCTION_REJECTED:
3262 	default:
3263 		return ISCSI_TMF_RSP_REJECTED;
3264 	}
3265 }
3266 
3267 void
3268 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3269 			  struct iscsi_tm_rsp *hdr)
3270 {
3271 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3272 
3273 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3274 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3275 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3276 	hdr->itt		= cmd->init_task_tag;
3277 	cmd->stat_sn		= conn->stat_sn++;
3278 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3279 
3280 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3281 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3282 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3283 
3284 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3285 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3286 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3287 }
3288 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3289 
3290 static int
3291 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3292 {
3293 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3294 
3295 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3296 
3297 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3298 }
3299 
3300 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3301 {
3302 	bool ret = false;
3303 
3304 	if (np->np_sockaddr.ss_family == AF_INET6) {
3305 		const struct sockaddr_in6 sin6 = {
3306 			.sin6_addr = IN6ADDR_ANY_INIT };
3307 		struct sockaddr_in6 *sock_in6 =
3308 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3309 
3310 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3311 				sin6.sin6_addr.s6_addr, 16))
3312 			ret = true;
3313 	} else {
3314 		struct sockaddr_in * sock_in =
3315 			(struct sockaddr_in *)&np->np_sockaddr;
3316 
3317 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3318 			ret = true;
3319 	}
3320 
3321 	return ret;
3322 }
3323 
3324 #define SENDTARGETS_BUF_LIMIT 32768U
3325 
3326 static int
3327 iscsit_build_sendtargets_response(struct iscsi_cmd *cmd,
3328 				  enum iscsit_transport_type network_transport,
3329 				  int skip_bytes, bool *completed)
3330 {
3331 	char *payload = NULL;
3332 	struct iscsi_conn *conn = cmd->conn;
3333 	struct iscsi_portal_group *tpg;
3334 	struct iscsi_tiqn *tiqn;
3335 	struct iscsi_tpg_np *tpg_np;
3336 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3337 	int target_name_printed;
3338 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3339 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3340 	bool active;
3341 
3342 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3343 			 SENDTARGETS_BUF_LIMIT);
3344 
3345 	payload = kzalloc(buffer_len, GFP_KERNEL);
3346 	if (!payload) {
3347 		pr_err("Unable to allocate memory for sendtargets"
3348 				" response.\n");
3349 		return -ENOMEM;
3350 	}
3351 	/*
3352 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3353 	 * explicit case..
3354 	 */
3355 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3356 		text_ptr = strchr(text_in, '=');
3357 		if (!text_ptr) {
3358 			pr_err("Unable to locate '=' string in text_in:"
3359 			       " %s\n", text_in);
3360 			kfree(payload);
3361 			return -EINVAL;
3362 		}
3363 		/*
3364 		 * Skip over '=' character..
3365 		 */
3366 		text_ptr += 1;
3367 	}
3368 
3369 	spin_lock(&tiqn_lock);
3370 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3371 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3372 		     strcmp(tiqn->tiqn, text_ptr)) {
3373 			continue;
3374 		}
3375 
3376 		target_name_printed = 0;
3377 
3378 		spin_lock(&tiqn->tiqn_tpg_lock);
3379 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3380 
3381 			/* If demo_mode_discovery=0 and generate_node_acls=0
3382 			 * (demo mode dislabed) do not return
3383 			 * TargetName+TargetAddress unless a NodeACL exists.
3384 			 */
3385 
3386 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3387 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3388 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3389 				cmd->conn->sess->sess_ops->InitiatorName))) {
3390 				continue;
3391 			}
3392 
3393 			spin_lock(&tpg->tpg_state_lock);
3394 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3395 			spin_unlock(&tpg->tpg_state_lock);
3396 
3397 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3398 				continue;
3399 
3400 			spin_lock(&tpg->tpg_np_lock);
3401 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3402 						tpg_np_list) {
3403 				struct iscsi_np *np = tpg_np->tpg_np;
3404 				bool inaddr_any = iscsit_check_inaddr_any(np);
3405 				struct sockaddr_storage *sockaddr;
3406 
3407 				if (np->np_network_transport != network_transport)
3408 					continue;
3409 
3410 				if (!target_name_printed) {
3411 					len = sprintf(buf, "TargetName=%s",
3412 						      tiqn->tiqn);
3413 					len += 1;
3414 
3415 					if ((len + payload_len) > buffer_len) {
3416 						spin_unlock(&tpg->tpg_np_lock);
3417 						spin_unlock(&tiqn->tiqn_tpg_lock);
3418 						end_of_buf = 1;
3419 						goto eob;
3420 					}
3421 
3422 					if (skip_bytes && len <= skip_bytes) {
3423 						skip_bytes -= len;
3424 					} else {
3425 						memcpy(payload + payload_len, buf, len);
3426 						payload_len += len;
3427 						target_name_printed = 1;
3428 						if (len > skip_bytes)
3429 							skip_bytes = 0;
3430 					}
3431 				}
3432 
3433 				if (inaddr_any)
3434 					sockaddr = &conn->local_sockaddr;
3435 				else
3436 					sockaddr = &np->np_sockaddr;
3437 
3438 				len = sprintf(buf, "TargetAddress="
3439 					      "%pISpc,%hu",
3440 					      sockaddr,
3441 					      tpg->tpgt);
3442 				len += 1;
3443 
3444 				if ((len + payload_len) > buffer_len) {
3445 					spin_unlock(&tpg->tpg_np_lock);
3446 					spin_unlock(&tiqn->tiqn_tpg_lock);
3447 					end_of_buf = 1;
3448 					goto eob;
3449 				}
3450 
3451 				if (skip_bytes && len <= skip_bytes) {
3452 					skip_bytes -= len;
3453 				} else {
3454 					memcpy(payload + payload_len, buf, len);
3455 					payload_len += len;
3456 					if (len > skip_bytes)
3457 						skip_bytes = 0;
3458 				}
3459 			}
3460 			spin_unlock(&tpg->tpg_np_lock);
3461 		}
3462 		spin_unlock(&tiqn->tiqn_tpg_lock);
3463 eob:
3464 		if (end_of_buf) {
3465 			*completed = false;
3466 			break;
3467 		}
3468 
3469 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3470 			break;
3471 	}
3472 	spin_unlock(&tiqn_lock);
3473 
3474 	cmd->buf_ptr = payload;
3475 
3476 	return payload_len;
3477 }
3478 
3479 int
3480 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3481 		      struct iscsi_text_rsp *hdr,
3482 		      enum iscsit_transport_type network_transport)
3483 {
3484 	int text_length, padding;
3485 	bool completed = true;
3486 
3487 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3488 							cmd->read_data_done,
3489 							&completed);
3490 	if (text_length < 0)
3491 		return text_length;
3492 
3493 	if (completed) {
3494 		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3495 	} else {
3496 		hdr->flags |= ISCSI_FLAG_TEXT_CONTINUE;
3497 		cmd->read_data_done += text_length;
3498 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3499 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3500 	}
3501 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3502 	padding = ((-text_length) & 3);
3503 	hton24(hdr->dlength, text_length);
3504 	hdr->itt = cmd->init_task_tag;
3505 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3506 	cmd->stat_sn = conn->stat_sn++;
3507 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3508 
3509 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3510 	/*
3511 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3512 	 * correctly increment MaxCmdSN for each response answering a
3513 	 * non immediate text request with a valid CmdSN.
3514 	 */
3515 	cmd->maxcmdsn_inc = 0;
3516 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3517 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3518 
3519 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3520 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3521 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3522 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3523 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3524 
3525 	return text_length + padding;
3526 }
3527 EXPORT_SYMBOL(iscsit_build_text_rsp);
3528 
3529 static int iscsit_send_text_rsp(
3530 	struct iscsi_cmd *cmd,
3531 	struct iscsi_conn *conn)
3532 {
3533 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3534 	int text_length;
3535 
3536 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3537 				conn->conn_transport->transport_type);
3538 	if (text_length < 0)
3539 		return text_length;
3540 
3541 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3542 						     cmd->buf_ptr,
3543 						     text_length);
3544 }
3545 
3546 void
3547 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3548 		    struct iscsi_reject *hdr)
3549 {
3550 	hdr->opcode		= ISCSI_OP_REJECT;
3551 	hdr->reason		= cmd->reject_reason;
3552 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3553 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3554 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3555 	cmd->stat_sn		= conn->stat_sn++;
3556 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3557 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3558 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3559 
3560 }
3561 EXPORT_SYMBOL(iscsit_build_reject);
3562 
3563 static int iscsit_send_reject(
3564 	struct iscsi_cmd *cmd,
3565 	struct iscsi_conn *conn)
3566 {
3567 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3568 
3569 	iscsit_build_reject(cmd, conn, hdr);
3570 
3571 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3572 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3573 
3574 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3575 						     cmd->buf_ptr,
3576 						     ISCSI_HDR_LEN);
3577 }
3578 
3579 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3580 {
3581 	int ord, cpu;
3582 	/*
3583 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3584 	 * within iscsit_start_kthreads()
3585 	 *
3586 	 * Here we use bitmap_id to determine which CPU that this
3587 	 * iSCSI connection's RX/TX threads will be scheduled to
3588 	 * execute upon.
3589 	 */
3590 	ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3591 	for_each_online_cpu(cpu) {
3592 		if (ord-- == 0) {
3593 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3594 			return;
3595 		}
3596 	}
3597 	/*
3598 	 * This should never be reached..
3599 	 */
3600 	dump_stack();
3601 	cpumask_setall(conn->conn_cpumask);
3602 }
3603 
3604 int
3605 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3606 {
3607 	int ret;
3608 
3609 	switch (state) {
3610 	case ISTATE_SEND_R2T:
3611 		ret = iscsit_send_r2t(cmd, conn);
3612 		if (ret < 0)
3613 			goto err;
3614 		break;
3615 	case ISTATE_REMOVE:
3616 		spin_lock_bh(&conn->cmd_lock);
3617 		list_del_init(&cmd->i_conn_node);
3618 		spin_unlock_bh(&conn->cmd_lock);
3619 
3620 		iscsit_free_cmd(cmd, false);
3621 		break;
3622 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3623 		iscsit_mod_nopin_response_timer(conn);
3624 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3625 		if (ret < 0)
3626 			goto err;
3627 		break;
3628 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3629 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3630 		if (ret < 0)
3631 			goto err;
3632 		break;
3633 	default:
3634 		pr_err("Unknown Opcode: 0x%02x ITT:"
3635 		       " 0x%08x, i_state: %d on CID: %hu\n",
3636 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3637 		       conn->cid);
3638 		goto err;
3639 	}
3640 
3641 	return 0;
3642 
3643 err:
3644 	return -1;
3645 }
3646 EXPORT_SYMBOL(iscsit_immediate_queue);
3647 
3648 static int
3649 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3650 {
3651 	struct iscsit_transport *t = conn->conn_transport;
3652 	struct iscsi_queue_req *qr;
3653 	struct iscsi_cmd *cmd;
3654 	u8 state;
3655 	int ret;
3656 
3657 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3658 		atomic_set(&conn->check_immediate_queue, 0);
3659 		cmd = qr->cmd;
3660 		state = qr->state;
3661 		kmem_cache_free(lio_qr_cache, qr);
3662 
3663 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3664 		if (ret < 0)
3665 			return ret;
3666 	}
3667 
3668 	return 0;
3669 }
3670 
3671 int
3672 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3673 {
3674 	int ret;
3675 
3676 check_rsp_state:
3677 	switch (state) {
3678 	case ISTATE_SEND_DATAIN:
3679 		ret = iscsit_send_datain(cmd, conn);
3680 		if (ret < 0)
3681 			goto err;
3682 		else if (!ret)
3683 			/* more drs */
3684 			goto check_rsp_state;
3685 		else if (ret == 1) {
3686 			/* all done */
3687 			spin_lock_bh(&cmd->istate_lock);
3688 			cmd->i_state = ISTATE_SENT_STATUS;
3689 			spin_unlock_bh(&cmd->istate_lock);
3690 
3691 			if (atomic_read(&conn->check_immediate_queue))
3692 				return 1;
3693 
3694 			return 0;
3695 		} else if (ret == 2) {
3696 			/* Still must send status,
3697 			   SCF_TRANSPORT_TASK_SENSE was set */
3698 			spin_lock_bh(&cmd->istate_lock);
3699 			cmd->i_state = ISTATE_SEND_STATUS;
3700 			spin_unlock_bh(&cmd->istate_lock);
3701 			state = ISTATE_SEND_STATUS;
3702 			goto check_rsp_state;
3703 		}
3704 
3705 		break;
3706 	case ISTATE_SEND_STATUS:
3707 	case ISTATE_SEND_STATUS_RECOVERY:
3708 		ret = iscsit_send_response(cmd, conn);
3709 		break;
3710 	case ISTATE_SEND_LOGOUTRSP:
3711 		ret = iscsit_send_logout(cmd, conn);
3712 		break;
3713 	case ISTATE_SEND_ASYNCMSG:
3714 		ret = iscsit_send_conn_drop_async_message(
3715 			cmd, conn);
3716 		break;
3717 	case ISTATE_SEND_NOPIN:
3718 		ret = iscsit_send_nopin(cmd, conn);
3719 		break;
3720 	case ISTATE_SEND_REJECT:
3721 		ret = iscsit_send_reject(cmd, conn);
3722 		break;
3723 	case ISTATE_SEND_TASKMGTRSP:
3724 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3725 		if (ret != 0)
3726 			break;
3727 		ret = iscsit_tmr_post_handler(cmd, conn);
3728 		if (ret != 0)
3729 			iscsit_fall_back_to_erl0(conn->sess);
3730 		break;
3731 	case ISTATE_SEND_TEXTRSP:
3732 		ret = iscsit_send_text_rsp(cmd, conn);
3733 		break;
3734 	default:
3735 		pr_err("Unknown Opcode: 0x%02x ITT:"
3736 		       " 0x%08x, i_state: %d on CID: %hu\n",
3737 		       cmd->iscsi_opcode, cmd->init_task_tag,
3738 		       state, conn->cid);
3739 		goto err;
3740 	}
3741 	if (ret < 0)
3742 		goto err;
3743 
3744 	switch (state) {
3745 	case ISTATE_SEND_LOGOUTRSP:
3746 		if (!iscsit_logout_post_handler(cmd, conn))
3747 			return -ECONNRESET;
3748 		/* fall through */
3749 	case ISTATE_SEND_STATUS:
3750 	case ISTATE_SEND_ASYNCMSG:
3751 	case ISTATE_SEND_NOPIN:
3752 	case ISTATE_SEND_STATUS_RECOVERY:
3753 	case ISTATE_SEND_TEXTRSP:
3754 	case ISTATE_SEND_TASKMGTRSP:
3755 	case ISTATE_SEND_REJECT:
3756 		spin_lock_bh(&cmd->istate_lock);
3757 		cmd->i_state = ISTATE_SENT_STATUS;
3758 		spin_unlock_bh(&cmd->istate_lock);
3759 		break;
3760 	default:
3761 		pr_err("Unknown Opcode: 0x%02x ITT:"
3762 		       " 0x%08x, i_state: %d on CID: %hu\n",
3763 		       cmd->iscsi_opcode, cmd->init_task_tag,
3764 		       cmd->i_state, conn->cid);
3765 		goto err;
3766 	}
3767 
3768 	if (atomic_read(&conn->check_immediate_queue))
3769 		return 1;
3770 
3771 	return 0;
3772 
3773 err:
3774 	return -1;
3775 }
3776 EXPORT_SYMBOL(iscsit_response_queue);
3777 
3778 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3779 {
3780 	struct iscsit_transport *t = conn->conn_transport;
3781 	struct iscsi_queue_req *qr;
3782 	struct iscsi_cmd *cmd;
3783 	u8 state;
3784 	int ret;
3785 
3786 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3787 		cmd = qr->cmd;
3788 		state = qr->state;
3789 		kmem_cache_free(lio_qr_cache, qr);
3790 
3791 		ret = t->iscsit_response_queue(conn, cmd, state);
3792 		if (ret == 1 || ret < 0)
3793 			return ret;
3794 	}
3795 
3796 	return 0;
3797 }
3798 
3799 int iscsi_target_tx_thread(void *arg)
3800 {
3801 	int ret = 0;
3802 	struct iscsi_conn *conn = arg;
3803 	/*
3804 	 * Allow ourselves to be interrupted by SIGINT so that a
3805 	 * connection recovery / failure event can be triggered externally.
3806 	 */
3807 	allow_signal(SIGINT);
3808 
3809 	while (!kthread_should_stop()) {
3810 		/*
3811 		 * Ensure that both TX and RX per connection kthreads
3812 		 * are scheduled to run on the same CPU.
3813 		 */
3814 		iscsit_thread_check_cpumask(conn, current, 1);
3815 
3816 		wait_event_interruptible(conn->queues_wq,
3817 					 !iscsit_conn_all_queues_empty(conn));
3818 
3819 		if (signal_pending(current))
3820 			goto transport_err;
3821 
3822 get_immediate:
3823 		ret = iscsit_handle_immediate_queue(conn);
3824 		if (ret < 0)
3825 			goto transport_err;
3826 
3827 		ret = iscsit_handle_response_queue(conn);
3828 		if (ret == 1)
3829 			goto get_immediate;
3830 		else if (ret == -ECONNRESET)
3831 			goto out;
3832 		else if (ret < 0)
3833 			goto transport_err;
3834 	}
3835 
3836 transport_err:
3837 	/*
3838 	 * Avoid the normal connection failure code-path if this connection
3839 	 * is still within LOGIN mode, and iscsi_np process context is
3840 	 * responsible for cleaning up the early connection failure.
3841 	 */
3842 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3843 		iscsit_take_action_for_connection_exit(conn);
3844 out:
3845 	return 0;
3846 }
3847 
3848 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3849 {
3850 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3851 	struct iscsi_cmd *cmd;
3852 	int ret = 0;
3853 
3854 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3855 	case ISCSI_OP_SCSI_CMD:
3856 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3857 		if (!cmd)
3858 			goto reject;
3859 
3860 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3861 		break;
3862 	case ISCSI_OP_SCSI_DATA_OUT:
3863 		ret = iscsit_handle_data_out(conn, buf);
3864 		break;
3865 	case ISCSI_OP_NOOP_OUT:
3866 		cmd = NULL;
3867 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3868 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3869 			if (!cmd)
3870 				goto reject;
3871 		}
3872 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3873 		break;
3874 	case ISCSI_OP_SCSI_TMFUNC:
3875 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3876 		if (!cmd)
3877 			goto reject;
3878 
3879 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3880 		break;
3881 	case ISCSI_OP_TEXT:
3882 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3883 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3884 			if (!cmd)
3885 				goto reject;
3886 		} else {
3887 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3888 			if (!cmd)
3889 				goto reject;
3890 		}
3891 
3892 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3893 		break;
3894 	case ISCSI_OP_LOGOUT:
3895 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3896 		if (!cmd)
3897 			goto reject;
3898 
3899 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3900 		if (ret > 0)
3901 			wait_for_completion_timeout(&conn->conn_logout_comp,
3902 					SECONDS_FOR_LOGOUT_COMP * HZ);
3903 		break;
3904 	case ISCSI_OP_SNACK:
3905 		ret = iscsit_handle_snack(conn, buf);
3906 		break;
3907 	default:
3908 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3909 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3910 			pr_err("Cannot recover from unknown"
3911 			" opcode while ERL=0, closing iSCSI connection.\n");
3912 			return -1;
3913 		}
3914 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
3915 		       " closing iSCSI connection.\n");
3916 		ret = -1;
3917 		break;
3918 	}
3919 
3920 	return ret;
3921 reject:
3922 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
3923 }
3924 
3925 static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
3926 {
3927 	bool ret;
3928 
3929 	spin_lock_bh(&conn->state_lock);
3930 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
3931 	spin_unlock_bh(&conn->state_lock);
3932 
3933 	return ret;
3934 }
3935 
3936 static void iscsit_get_rx_pdu(struct iscsi_conn *conn)
3937 {
3938 	int ret;
3939 	u8 buffer[ISCSI_HDR_LEN], opcode;
3940 	u32 checksum = 0, digest = 0;
3941 	struct kvec iov;
3942 
3943 	while (!kthread_should_stop()) {
3944 		/*
3945 		 * Ensure that both TX and RX per connection kthreads
3946 		 * are scheduled to run on the same CPU.
3947 		 */
3948 		iscsit_thread_check_cpumask(conn, current, 0);
3949 
3950 		memset(buffer, 0, ISCSI_HDR_LEN);
3951 		memset(&iov, 0, sizeof(struct kvec));
3952 
3953 		iov.iov_base	= buffer;
3954 		iov.iov_len	= ISCSI_HDR_LEN;
3955 
3956 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
3957 		if (ret != ISCSI_HDR_LEN) {
3958 			iscsit_rx_thread_wait_for_tcp(conn);
3959 			return;
3960 		}
3961 
3962 		if (conn->conn_ops->HeaderDigest) {
3963 			iov.iov_base	= &digest;
3964 			iov.iov_len	= ISCSI_CRC_LEN;
3965 
3966 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
3967 			if (ret != ISCSI_CRC_LEN) {
3968 				iscsit_rx_thread_wait_for_tcp(conn);
3969 				return;
3970 			}
3971 
3972 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
3973 					buffer, ISCSI_HDR_LEN,
3974 					0, NULL, (u8 *)&checksum);
3975 
3976 			if (digest != checksum) {
3977 				pr_err("HeaderDigest CRC32C failed,"
3978 					" received 0x%08x, computed 0x%08x\n",
3979 					digest, checksum);
3980 				/*
3981 				 * Set the PDU to 0xff so it will intentionally
3982 				 * hit default in the switch below.
3983 				 */
3984 				memset(buffer, 0xff, ISCSI_HDR_LEN);
3985 				atomic_long_inc(&conn->sess->conn_digest_errors);
3986 			} else {
3987 				pr_debug("Got HeaderDigest CRC32C"
3988 						" 0x%08x\n", checksum);
3989 			}
3990 		}
3991 
3992 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
3993 			return;
3994 
3995 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
3996 
3997 		if (conn->sess->sess_ops->SessionType &&
3998 		   ((!(opcode & ISCSI_OP_TEXT)) ||
3999 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4000 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4001 			" while in Discovery Session, rejecting.\n", opcode);
4002 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4003 					  buffer);
4004 			return;
4005 		}
4006 
4007 		ret = iscsi_target_rx_opcode(conn, buffer);
4008 		if (ret < 0)
4009 			return;
4010 	}
4011 }
4012 
4013 int iscsi_target_rx_thread(void *arg)
4014 {
4015 	int rc;
4016 	struct iscsi_conn *conn = arg;
4017 
4018 	/*
4019 	 * Allow ourselves to be interrupted by SIGINT so that a
4020 	 * connection recovery / failure event can be triggered externally.
4021 	 */
4022 	allow_signal(SIGINT);
4023 	/*
4024 	 * Wait for iscsi_post_login_handler() to complete before allowing
4025 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4026 	 */
4027 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4028 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4029 		return 0;
4030 
4031 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4032 		return 0;
4033 
4034 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4035 
4036 	if (!signal_pending(current))
4037 		atomic_set(&conn->transport_failed, 1);
4038 	iscsit_take_action_for_connection_exit(conn);
4039 	return 0;
4040 }
4041 
4042 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4043 {
4044 	LIST_HEAD(tmp_list);
4045 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4046 	struct iscsi_session *sess = conn->sess;
4047 	/*
4048 	 * We expect this function to only ever be called from either RX or TX
4049 	 * thread context via iscsit_close_connection() once the other context
4050 	 * has been reset -> returned sleeping pre-handler state.
4051 	 */
4052 	spin_lock_bh(&conn->cmd_lock);
4053 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4054 
4055 	list_for_each_entry(cmd, &tmp_list, i_conn_node) {
4056 		struct se_cmd *se_cmd = &cmd->se_cmd;
4057 
4058 		if (se_cmd->se_tfo != NULL) {
4059 			spin_lock(&se_cmd->t_state_lock);
4060 			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4061 			spin_unlock(&se_cmd->t_state_lock);
4062 		}
4063 	}
4064 	spin_unlock_bh(&conn->cmd_lock);
4065 
4066 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4067 		list_del_init(&cmd->i_conn_node);
4068 
4069 		iscsit_increment_maxcmdsn(cmd, sess);
4070 		iscsit_free_cmd(cmd, true);
4071 
4072 	}
4073 }
4074 
4075 static void iscsit_stop_timers_for_cmds(
4076 	struct iscsi_conn *conn)
4077 {
4078 	struct iscsi_cmd *cmd;
4079 
4080 	spin_lock_bh(&conn->cmd_lock);
4081 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4082 		if (cmd->data_direction == DMA_TO_DEVICE)
4083 			iscsit_stop_dataout_timer(cmd);
4084 	}
4085 	spin_unlock_bh(&conn->cmd_lock);
4086 }
4087 
4088 int iscsit_close_connection(
4089 	struct iscsi_conn *conn)
4090 {
4091 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4092 	struct iscsi_session	*sess = conn->sess;
4093 
4094 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4095 		" %u\n", conn->cid, sess->sid);
4096 	/*
4097 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4098 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4099 	 * sleeping and the logout response never got sent because the
4100 	 * connection failed.
4101 	 *
4102 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4103 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4104 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4105 	 * and to avoid iscsi_conn pointer dereference in iser-target code.
4106 	 */
4107 	if (!conn->conn_transport->rdma_shutdown)
4108 		complete(&conn->conn_logout_comp);
4109 
4110 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4111 		if (conn->tx_thread &&
4112 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4113 			send_sig(SIGINT, conn->tx_thread, 1);
4114 			kthread_stop(conn->tx_thread);
4115 		}
4116 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4117 		if (conn->rx_thread &&
4118 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4119 			send_sig(SIGINT, conn->rx_thread, 1);
4120 			kthread_stop(conn->rx_thread);
4121 		}
4122 	}
4123 
4124 	spin_lock(&iscsit_global->ts_bitmap_lock);
4125 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4126 			      get_order(1));
4127 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4128 
4129 	iscsit_stop_timers_for_cmds(conn);
4130 	iscsit_stop_nopin_response_timer(conn);
4131 	iscsit_stop_nopin_timer(conn);
4132 
4133 	if (conn->conn_transport->iscsit_wait_conn)
4134 		conn->conn_transport->iscsit_wait_conn(conn);
4135 
4136 	/*
4137 	 * During Connection recovery drop unacknowledged out of order
4138 	 * commands for this connection, and prepare the other commands
4139 	 * for realligence.
4140 	 *
4141 	 * During normal operation clear the out of order commands (but
4142 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4143 	 * struct iscsi_cmds.
4144 	 */
4145 	if (atomic_read(&conn->connection_recovery)) {
4146 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4147 		iscsit_prepare_cmds_for_realligance(conn);
4148 	} else {
4149 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4150 		iscsit_release_commands_from_conn(conn);
4151 	}
4152 	iscsit_free_queue_reqs_for_conn(conn);
4153 
4154 	/*
4155 	 * Handle decrementing session or connection usage count if
4156 	 * a logout response was not able to be sent because the
4157 	 * connection failed.  Fall back to Session Recovery here.
4158 	 */
4159 	if (atomic_read(&conn->conn_logout_remove)) {
4160 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4161 			iscsit_dec_conn_usage_count(conn);
4162 			iscsit_dec_session_usage_count(sess);
4163 		}
4164 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4165 			iscsit_dec_conn_usage_count(conn);
4166 
4167 		atomic_set(&conn->conn_logout_remove, 0);
4168 		atomic_set(&sess->session_reinstatement, 0);
4169 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4170 	}
4171 
4172 	spin_lock_bh(&sess->conn_lock);
4173 	list_del(&conn->conn_list);
4174 
4175 	/*
4176 	 * Attempt to let the Initiator know this connection failed by
4177 	 * sending an Connection Dropped Async Message on another
4178 	 * active connection.
4179 	 */
4180 	if (atomic_read(&conn->connection_recovery))
4181 		iscsit_build_conn_drop_async_message(conn);
4182 
4183 	spin_unlock_bh(&sess->conn_lock);
4184 
4185 	/*
4186 	 * If connection reinstatement is being performed on this connection,
4187 	 * up the connection reinstatement semaphore that is being blocked on
4188 	 * in iscsit_cause_connection_reinstatement().
4189 	 */
4190 	spin_lock_bh(&conn->state_lock);
4191 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4192 		spin_unlock_bh(&conn->state_lock);
4193 		complete(&conn->conn_wait_comp);
4194 		wait_for_completion(&conn->conn_post_wait_comp);
4195 		spin_lock_bh(&conn->state_lock);
4196 	}
4197 
4198 	/*
4199 	 * If connection reinstatement is being performed on this connection
4200 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4201 	 * connection wait rcfr semaphore that is being blocked on
4202 	 * an iscsit_connection_reinstatement_rcfr().
4203 	 */
4204 	if (atomic_read(&conn->connection_wait_rcfr)) {
4205 		spin_unlock_bh(&conn->state_lock);
4206 		complete(&conn->conn_wait_rcfr_comp);
4207 		wait_for_completion(&conn->conn_post_wait_comp);
4208 		spin_lock_bh(&conn->state_lock);
4209 	}
4210 	atomic_set(&conn->connection_reinstatement, 1);
4211 	spin_unlock_bh(&conn->state_lock);
4212 
4213 	/*
4214 	 * If any other processes are accessing this connection pointer we
4215 	 * must wait until they have completed.
4216 	 */
4217 	iscsit_check_conn_usage_count(conn);
4218 
4219 	ahash_request_free(conn->conn_tx_hash);
4220 	if (conn->conn_rx_hash) {
4221 		struct crypto_ahash *tfm;
4222 
4223 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4224 		ahash_request_free(conn->conn_rx_hash);
4225 		crypto_free_ahash(tfm);
4226 	}
4227 
4228 	free_cpumask_var(conn->conn_cpumask);
4229 
4230 	kfree(conn->conn_ops);
4231 	conn->conn_ops = NULL;
4232 
4233 	if (conn->sock)
4234 		sock_release(conn->sock);
4235 
4236 	if (conn->conn_transport->iscsit_free_conn)
4237 		conn->conn_transport->iscsit_free_conn(conn);
4238 
4239 	iscsit_put_transport(conn->conn_transport);
4240 
4241 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4242 	conn->conn_state = TARG_CONN_STATE_FREE;
4243 	kfree(conn);
4244 
4245 	spin_lock_bh(&sess->conn_lock);
4246 	atomic_dec(&sess->nconn);
4247 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4248 		" %s\n", atomic_read(&sess->nconn),
4249 		sess->sess_ops->InitiatorName);
4250 	/*
4251 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4252 	 * Session that they all fail.
4253 	 */
4254 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4255 	     !atomic_read(&sess->session_logout))
4256 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4257 
4258 	/*
4259 	 * If this was not the last connection in the session, and we are
4260 	 * performing session reinstatement or falling back to ERL=0, call
4261 	 * iscsit_stop_session() without sleeping to shutdown the other
4262 	 * active connections.
4263 	 */
4264 	if (atomic_read(&sess->nconn)) {
4265 		if (!atomic_read(&sess->session_reinstatement) &&
4266 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4267 			spin_unlock_bh(&sess->conn_lock);
4268 			return 0;
4269 		}
4270 		if (!atomic_read(&sess->session_stop_active)) {
4271 			atomic_set(&sess->session_stop_active, 1);
4272 			spin_unlock_bh(&sess->conn_lock);
4273 			iscsit_stop_session(sess, 0, 0);
4274 			return 0;
4275 		}
4276 		spin_unlock_bh(&sess->conn_lock);
4277 		return 0;
4278 	}
4279 
4280 	/*
4281 	 * If this was the last connection in the session and one of the
4282 	 * following is occurring:
4283 	 *
4284 	 * Session Reinstatement is not being performed, and are falling back
4285 	 * to ERL=0 call iscsit_close_session().
4286 	 *
4287 	 * Session Logout was requested.  iscsit_close_session() will be called
4288 	 * elsewhere.
4289 	 *
4290 	 * Session Continuation is not being performed, start the Time2Retain
4291 	 * handler and check if sleep_on_sess_wait_sem is active.
4292 	 */
4293 	if (!atomic_read(&sess->session_reinstatement) &&
4294 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4295 		spin_unlock_bh(&sess->conn_lock);
4296 		iscsit_close_session(sess);
4297 
4298 		return 0;
4299 	} else if (atomic_read(&sess->session_logout)) {
4300 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4301 		sess->session_state = TARG_SESS_STATE_FREE;
4302 		spin_unlock_bh(&sess->conn_lock);
4303 
4304 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4305 			complete(&sess->session_wait_comp);
4306 
4307 		return 0;
4308 	} else {
4309 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4310 		sess->session_state = TARG_SESS_STATE_FAILED;
4311 
4312 		if (!atomic_read(&sess->session_continuation)) {
4313 			spin_unlock_bh(&sess->conn_lock);
4314 			iscsit_start_time2retain_handler(sess);
4315 		} else
4316 			spin_unlock_bh(&sess->conn_lock);
4317 
4318 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4319 			complete(&sess->session_wait_comp);
4320 
4321 		return 0;
4322 	}
4323 }
4324 
4325 /*
4326  * If the iSCSI Session for the iSCSI Initiator Node exists,
4327  * forcefully shutdown the iSCSI NEXUS.
4328  */
4329 int iscsit_close_session(struct iscsi_session *sess)
4330 {
4331 	struct iscsi_portal_group *tpg = sess->tpg;
4332 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4333 
4334 	if (atomic_read(&sess->nconn)) {
4335 		pr_err("%d connection(s) still exist for iSCSI session"
4336 			" to %s\n", atomic_read(&sess->nconn),
4337 			sess->sess_ops->InitiatorName);
4338 		BUG();
4339 	}
4340 
4341 	spin_lock_bh(&se_tpg->session_lock);
4342 	atomic_set(&sess->session_logout, 1);
4343 	atomic_set(&sess->session_reinstatement, 1);
4344 	iscsit_stop_time2retain_timer(sess);
4345 	spin_unlock_bh(&se_tpg->session_lock);
4346 
4347 	/*
4348 	 * transport_deregister_session_configfs() will clear the
4349 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4350 	 * can be setting it again with __transport_register_session() in
4351 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4352 	 * completes in iscsi_np context.
4353 	 */
4354 	transport_deregister_session_configfs(sess->se_sess);
4355 
4356 	/*
4357 	 * If any other processes are accessing this session pointer we must
4358 	 * wait until they have completed.  If we are in an interrupt (the
4359 	 * time2retain handler) and contain and active session usage count we
4360 	 * restart the timer and exit.
4361 	 */
4362 	if (!in_interrupt()) {
4363 		if (iscsit_check_session_usage_count(sess) == 1)
4364 			iscsit_stop_session(sess, 1, 1);
4365 	} else {
4366 		if (iscsit_check_session_usage_count(sess) == 2) {
4367 			atomic_set(&sess->session_logout, 0);
4368 			iscsit_start_time2retain_handler(sess);
4369 			return 0;
4370 		}
4371 	}
4372 
4373 	transport_deregister_session(sess->se_sess);
4374 
4375 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4376 		iscsit_free_connection_recovery_entires(sess);
4377 
4378 	iscsit_free_all_ooo_cmdsns(sess);
4379 
4380 	spin_lock_bh(&se_tpg->session_lock);
4381 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4382 	sess->session_state = TARG_SESS_STATE_FREE;
4383 	pr_debug("Released iSCSI session from node: %s\n",
4384 			sess->sess_ops->InitiatorName);
4385 	tpg->nsessions--;
4386 	if (tpg->tpg_tiqn)
4387 		tpg->tpg_tiqn->tiqn_nsessions--;
4388 
4389 	pr_debug("Decremented number of active iSCSI Sessions on"
4390 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4391 
4392 	spin_lock(&sess_idr_lock);
4393 	idr_remove(&sess_idr, sess->session_index);
4394 	spin_unlock(&sess_idr_lock);
4395 
4396 	kfree(sess->sess_ops);
4397 	sess->sess_ops = NULL;
4398 	spin_unlock_bh(&se_tpg->session_lock);
4399 
4400 	kfree(sess);
4401 	return 0;
4402 }
4403 
4404 static void iscsit_logout_post_handler_closesession(
4405 	struct iscsi_conn *conn)
4406 {
4407 	struct iscsi_session *sess = conn->sess;
4408 	int sleep = 1;
4409 	/*
4410 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4411 	 * context during session logout, so clear tx_thread_active and
4412 	 * sleep if iscsit_close_connection() has not already occured.
4413 	 *
4414 	 * Since iser-target invokes this logic from it's own workqueue,
4415 	 * always sleep waiting for RX/TX thread shutdown to complete
4416 	 * within iscsit_close_connection().
4417 	 */
4418 	if (!conn->conn_transport->rdma_shutdown)
4419 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4420 
4421 	atomic_set(&conn->conn_logout_remove, 0);
4422 	complete(&conn->conn_logout_comp);
4423 
4424 	iscsit_dec_conn_usage_count(conn);
4425 	iscsit_stop_session(sess, sleep, sleep);
4426 	iscsit_dec_session_usage_count(sess);
4427 	iscsit_close_session(sess);
4428 }
4429 
4430 static void iscsit_logout_post_handler_samecid(
4431 	struct iscsi_conn *conn)
4432 {
4433 	int sleep = 1;
4434 
4435 	if (!conn->conn_transport->rdma_shutdown)
4436 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4437 
4438 	atomic_set(&conn->conn_logout_remove, 0);
4439 	complete(&conn->conn_logout_comp);
4440 
4441 	iscsit_cause_connection_reinstatement(conn, sleep);
4442 	iscsit_dec_conn_usage_count(conn);
4443 }
4444 
4445 static void iscsit_logout_post_handler_diffcid(
4446 	struct iscsi_conn *conn,
4447 	u16 cid)
4448 {
4449 	struct iscsi_conn *l_conn;
4450 	struct iscsi_session *sess = conn->sess;
4451 	bool conn_found = false;
4452 
4453 	if (!sess)
4454 		return;
4455 
4456 	spin_lock_bh(&sess->conn_lock);
4457 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4458 		if (l_conn->cid == cid) {
4459 			iscsit_inc_conn_usage_count(l_conn);
4460 			conn_found = true;
4461 			break;
4462 		}
4463 	}
4464 	spin_unlock_bh(&sess->conn_lock);
4465 
4466 	if (!conn_found)
4467 		return;
4468 
4469 	if (l_conn->sock)
4470 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4471 
4472 	spin_lock_bh(&l_conn->state_lock);
4473 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4474 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4475 	spin_unlock_bh(&l_conn->state_lock);
4476 
4477 	iscsit_cause_connection_reinstatement(l_conn, 1);
4478 	iscsit_dec_conn_usage_count(l_conn);
4479 }
4480 
4481 /*
4482  *	Return of 0 causes the TX thread to restart.
4483  */
4484 int iscsit_logout_post_handler(
4485 	struct iscsi_cmd *cmd,
4486 	struct iscsi_conn *conn)
4487 {
4488 	int ret = 0;
4489 
4490 	switch (cmd->logout_reason) {
4491 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4492 		switch (cmd->logout_response) {
4493 		case ISCSI_LOGOUT_SUCCESS:
4494 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4495 		default:
4496 			iscsit_logout_post_handler_closesession(conn);
4497 			break;
4498 		}
4499 		ret = 0;
4500 		break;
4501 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4502 		if (conn->cid == cmd->logout_cid) {
4503 			switch (cmd->logout_response) {
4504 			case ISCSI_LOGOUT_SUCCESS:
4505 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4506 			default:
4507 				iscsit_logout_post_handler_samecid(conn);
4508 				break;
4509 			}
4510 			ret = 0;
4511 		} else {
4512 			switch (cmd->logout_response) {
4513 			case ISCSI_LOGOUT_SUCCESS:
4514 				iscsit_logout_post_handler_diffcid(conn,
4515 					cmd->logout_cid);
4516 				break;
4517 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4518 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4519 			default:
4520 				break;
4521 			}
4522 			ret = 1;
4523 		}
4524 		break;
4525 	case ISCSI_LOGOUT_REASON_RECOVERY:
4526 		switch (cmd->logout_response) {
4527 		case ISCSI_LOGOUT_SUCCESS:
4528 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4529 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4530 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4531 		default:
4532 			break;
4533 		}
4534 		ret = 1;
4535 		break;
4536 	default:
4537 		break;
4538 
4539 	}
4540 	return ret;
4541 }
4542 EXPORT_SYMBOL(iscsit_logout_post_handler);
4543 
4544 void iscsit_fail_session(struct iscsi_session *sess)
4545 {
4546 	struct iscsi_conn *conn;
4547 
4548 	spin_lock_bh(&sess->conn_lock);
4549 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4550 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4551 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4552 	}
4553 	spin_unlock_bh(&sess->conn_lock);
4554 
4555 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4556 	sess->session_state = TARG_SESS_STATE_FAILED;
4557 }
4558 
4559 int iscsit_free_session(struct iscsi_session *sess)
4560 {
4561 	u16 conn_count = atomic_read(&sess->nconn);
4562 	struct iscsi_conn *conn, *conn_tmp = NULL;
4563 	int is_last;
4564 
4565 	spin_lock_bh(&sess->conn_lock);
4566 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4567 
4568 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4569 			conn_list) {
4570 		if (conn_count == 0)
4571 			break;
4572 
4573 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4574 			is_last = 1;
4575 		} else {
4576 			iscsit_inc_conn_usage_count(conn_tmp);
4577 			is_last = 0;
4578 		}
4579 		iscsit_inc_conn_usage_count(conn);
4580 
4581 		spin_unlock_bh(&sess->conn_lock);
4582 		iscsit_cause_connection_reinstatement(conn, 1);
4583 		spin_lock_bh(&sess->conn_lock);
4584 
4585 		iscsit_dec_conn_usage_count(conn);
4586 		if (is_last == 0)
4587 			iscsit_dec_conn_usage_count(conn_tmp);
4588 
4589 		conn_count--;
4590 	}
4591 
4592 	if (atomic_read(&sess->nconn)) {
4593 		spin_unlock_bh(&sess->conn_lock);
4594 		wait_for_completion(&sess->session_wait_comp);
4595 	} else
4596 		spin_unlock_bh(&sess->conn_lock);
4597 
4598 	iscsit_close_session(sess);
4599 	return 0;
4600 }
4601 
4602 void iscsit_stop_session(
4603 	struct iscsi_session *sess,
4604 	int session_sleep,
4605 	int connection_sleep)
4606 {
4607 	u16 conn_count = atomic_read(&sess->nconn);
4608 	struct iscsi_conn *conn, *conn_tmp = NULL;
4609 	int is_last;
4610 
4611 	spin_lock_bh(&sess->conn_lock);
4612 	if (session_sleep)
4613 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4614 
4615 	if (connection_sleep) {
4616 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4617 				conn_list) {
4618 			if (conn_count == 0)
4619 				break;
4620 
4621 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4622 				is_last = 1;
4623 			} else {
4624 				iscsit_inc_conn_usage_count(conn_tmp);
4625 				is_last = 0;
4626 			}
4627 			iscsit_inc_conn_usage_count(conn);
4628 
4629 			spin_unlock_bh(&sess->conn_lock);
4630 			iscsit_cause_connection_reinstatement(conn, 1);
4631 			spin_lock_bh(&sess->conn_lock);
4632 
4633 			iscsit_dec_conn_usage_count(conn);
4634 			if (is_last == 0)
4635 				iscsit_dec_conn_usage_count(conn_tmp);
4636 			conn_count--;
4637 		}
4638 	} else {
4639 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4640 			iscsit_cause_connection_reinstatement(conn, 0);
4641 	}
4642 
4643 	if (session_sleep && atomic_read(&sess->nconn)) {
4644 		spin_unlock_bh(&sess->conn_lock);
4645 		wait_for_completion(&sess->session_wait_comp);
4646 	} else
4647 		spin_unlock_bh(&sess->conn_lock);
4648 }
4649 
4650 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4651 {
4652 	struct iscsi_session *sess;
4653 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4654 	struct se_session *se_sess, *se_sess_tmp;
4655 	LIST_HEAD(free_list);
4656 	int session_count = 0;
4657 
4658 	spin_lock_bh(&se_tpg->session_lock);
4659 	if (tpg->nsessions && !force) {
4660 		spin_unlock_bh(&se_tpg->session_lock);
4661 		return -1;
4662 	}
4663 
4664 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4665 			sess_list) {
4666 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4667 
4668 		spin_lock(&sess->conn_lock);
4669 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4670 		    atomic_read(&sess->session_logout) ||
4671 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4672 			spin_unlock(&sess->conn_lock);
4673 			continue;
4674 		}
4675 		atomic_set(&sess->session_reinstatement, 1);
4676 		spin_unlock(&sess->conn_lock);
4677 
4678 		list_move_tail(&se_sess->sess_list, &free_list);
4679 	}
4680 	spin_unlock_bh(&se_tpg->session_lock);
4681 
4682 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4683 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4684 
4685 		iscsit_free_session(sess);
4686 		session_count++;
4687 	}
4688 
4689 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4690 			" Group: %hu\n", session_count, tpg->tpgt);
4691 	return 0;
4692 }
4693 
4694 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4695 MODULE_VERSION("4.1.x");
4696 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4697 MODULE_LICENSE("GPL");
4698 
4699 module_init(iscsi_target_init_module);
4700 module_exit(iscsi_target_cleanup_module);
4701