xref: /openbmc/linux/drivers/target/iscsi/iscsi_target.c (revision 4f139972b489f8bc2c821aa25ac65018d92af3f7)
1 /*******************************************************************************
2  * This file contains main functions related to the iSCSI Target Core Driver.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18 
19 #include <crypto/hash.h>
20 #include <linux/string.h>
21 #include <linux/kthread.h>
22 #include <linux/completion.h>
23 #include <linux/module.h>
24 #include <linux/vmalloc.h>
25 #include <linux/idr.h>
26 #include <linux/delay.h>
27 #include <linux/sched/signal.h>
28 #include <asm/unaligned.h>
29 #include <net/ipv6.h>
30 #include <scsi/scsi_proto.h>
31 #include <scsi/iscsi_proto.h>
32 #include <scsi/scsi_tcq.h>
33 #include <target/target_core_base.h>
34 #include <target/target_core_fabric.h>
35 
36 #include <target/iscsi/iscsi_target_core.h>
37 #include "iscsi_target_parameters.h"
38 #include "iscsi_target_seq_pdu_list.h"
39 #include "iscsi_target_datain_values.h"
40 #include "iscsi_target_erl0.h"
41 #include "iscsi_target_erl1.h"
42 #include "iscsi_target_erl2.h"
43 #include "iscsi_target_login.h"
44 #include "iscsi_target_tmr.h"
45 #include "iscsi_target_tpg.h"
46 #include "iscsi_target_util.h"
47 #include "iscsi_target.h"
48 #include "iscsi_target_device.h"
49 #include <target/iscsi/iscsi_target_stat.h>
50 
51 #include <target/iscsi/iscsi_transport.h>
52 
53 static LIST_HEAD(g_tiqn_list);
54 static LIST_HEAD(g_np_list);
55 static DEFINE_SPINLOCK(tiqn_lock);
56 static DEFINE_MUTEX(np_lock);
57 
58 static struct idr tiqn_idr;
59 struct idr sess_idr;
60 struct mutex auth_id_lock;
61 spinlock_t sess_idr_lock;
62 
63 struct iscsit_global *iscsit_global;
64 
65 struct kmem_cache *lio_qr_cache;
66 struct kmem_cache *lio_dr_cache;
67 struct kmem_cache *lio_ooo_cache;
68 struct kmem_cache *lio_r2t_cache;
69 
70 static int iscsit_handle_immediate_data(struct iscsi_cmd *,
71 			struct iscsi_scsi_req *, u32);
72 
73 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
74 {
75 	struct iscsi_tiqn *tiqn = NULL;
76 
77 	spin_lock(&tiqn_lock);
78 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
79 		if (!strcmp(tiqn->tiqn, buf)) {
80 
81 			spin_lock(&tiqn->tiqn_state_lock);
82 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
83 				tiqn->tiqn_access_count++;
84 				spin_unlock(&tiqn->tiqn_state_lock);
85 				spin_unlock(&tiqn_lock);
86 				return tiqn;
87 			}
88 			spin_unlock(&tiqn->tiqn_state_lock);
89 		}
90 	}
91 	spin_unlock(&tiqn_lock);
92 
93 	return NULL;
94 }
95 
96 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
97 {
98 	spin_lock(&tiqn->tiqn_state_lock);
99 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
100 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
101 		spin_unlock(&tiqn->tiqn_state_lock);
102 		return 0;
103 	}
104 	spin_unlock(&tiqn->tiqn_state_lock);
105 
106 	return -1;
107 }
108 
109 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
110 {
111 	spin_lock(&tiqn->tiqn_state_lock);
112 	tiqn->tiqn_access_count--;
113 	spin_unlock(&tiqn->tiqn_state_lock);
114 }
115 
116 /*
117  * Note that IQN formatting is expected to be done in userspace, and
118  * no explict IQN format checks are done here.
119  */
120 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
121 {
122 	struct iscsi_tiqn *tiqn = NULL;
123 	int ret;
124 
125 	if (strlen(buf) >= ISCSI_IQN_LEN) {
126 		pr_err("Target IQN exceeds %d bytes\n",
127 				ISCSI_IQN_LEN);
128 		return ERR_PTR(-EINVAL);
129 	}
130 
131 	tiqn = kzalloc(sizeof(struct iscsi_tiqn), GFP_KERNEL);
132 	if (!tiqn) {
133 		pr_err("Unable to allocate struct iscsi_tiqn\n");
134 		return ERR_PTR(-ENOMEM);
135 	}
136 
137 	sprintf(tiqn->tiqn, "%s", buf);
138 	INIT_LIST_HEAD(&tiqn->tiqn_list);
139 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
140 	spin_lock_init(&tiqn->tiqn_state_lock);
141 	spin_lock_init(&tiqn->tiqn_tpg_lock);
142 	spin_lock_init(&tiqn->sess_err_stats.lock);
143 	spin_lock_init(&tiqn->login_stats.lock);
144 	spin_lock_init(&tiqn->logout_stats.lock);
145 
146 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
147 
148 	idr_preload(GFP_KERNEL);
149 	spin_lock(&tiqn_lock);
150 
151 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
152 	if (ret < 0) {
153 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
154 		spin_unlock(&tiqn_lock);
155 		idr_preload_end();
156 		kfree(tiqn);
157 		return ERR_PTR(ret);
158 	}
159 	tiqn->tiqn_index = ret;
160 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
161 
162 	spin_unlock(&tiqn_lock);
163 	idr_preload_end();
164 
165 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
166 
167 	return tiqn;
168 
169 }
170 
171 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
172 {
173 	/*
174 	 * Wait for accesses to said struct iscsi_tiqn to end.
175 	 */
176 	spin_lock(&tiqn->tiqn_state_lock);
177 	while (tiqn->tiqn_access_count != 0) {
178 		spin_unlock(&tiqn->tiqn_state_lock);
179 		msleep(10);
180 		spin_lock(&tiqn->tiqn_state_lock);
181 	}
182 	spin_unlock(&tiqn->tiqn_state_lock);
183 }
184 
185 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
186 {
187 	/*
188 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
189 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
190 	 * attempts to access this struct iscsi_tiqn will fail from both transport
191 	 * fabric and control code paths.
192 	 */
193 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
194 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
195 		return;
196 	}
197 
198 	iscsit_wait_for_tiqn(tiqn);
199 
200 	spin_lock(&tiqn_lock);
201 	list_del(&tiqn->tiqn_list);
202 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
203 	spin_unlock(&tiqn_lock);
204 
205 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
206 			tiqn->tiqn);
207 	kfree(tiqn);
208 }
209 
210 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
211 {
212 	int ret;
213 	/*
214 	 * Determine if the network portal is accepting storage traffic.
215 	 */
216 	spin_lock_bh(&np->np_thread_lock);
217 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
218 		spin_unlock_bh(&np->np_thread_lock);
219 		return -1;
220 	}
221 	spin_unlock_bh(&np->np_thread_lock);
222 	/*
223 	 * Determine if the portal group is accepting storage traffic.
224 	 */
225 	spin_lock_bh(&tpg->tpg_state_lock);
226 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
227 		spin_unlock_bh(&tpg->tpg_state_lock);
228 		return -1;
229 	}
230 	spin_unlock_bh(&tpg->tpg_state_lock);
231 
232 	/*
233 	 * Here we serialize access across the TIQN+TPG Tuple.
234 	 */
235 	ret = down_interruptible(&tpg->np_login_sem);
236 	if (ret != 0)
237 		return -1;
238 
239 	spin_lock_bh(&tpg->tpg_state_lock);
240 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
241 		spin_unlock_bh(&tpg->tpg_state_lock);
242 		up(&tpg->np_login_sem);
243 		return -1;
244 	}
245 	spin_unlock_bh(&tpg->tpg_state_lock);
246 
247 	return 0;
248 }
249 
250 void iscsit_login_kref_put(struct kref *kref)
251 {
252 	struct iscsi_tpg_np *tpg_np = container_of(kref,
253 				struct iscsi_tpg_np, tpg_np_kref);
254 
255 	complete(&tpg_np->tpg_np_comp);
256 }
257 
258 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
259 		       struct iscsi_tpg_np *tpg_np)
260 {
261 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
262 
263 	up(&tpg->np_login_sem);
264 
265 	if (tpg_np)
266 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
267 
268 	if (tiqn)
269 		iscsit_put_tiqn_for_login(tiqn);
270 
271 	return 0;
272 }
273 
274 bool iscsit_check_np_match(
275 	struct sockaddr_storage *sockaddr,
276 	struct iscsi_np *np,
277 	int network_transport)
278 {
279 	struct sockaddr_in *sock_in, *sock_in_e;
280 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
281 	bool ip_match = false;
282 	u16 port, port_e;
283 
284 	if (sockaddr->ss_family == AF_INET6) {
285 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
286 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
287 
288 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
289 			    &sock_in6_e->sin6_addr.in6_u,
290 			    sizeof(struct in6_addr)))
291 			ip_match = true;
292 
293 		port = ntohs(sock_in6->sin6_port);
294 		port_e = ntohs(sock_in6_e->sin6_port);
295 	} else {
296 		sock_in = (struct sockaddr_in *)sockaddr;
297 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
298 
299 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
300 			ip_match = true;
301 
302 		port = ntohs(sock_in->sin_port);
303 		port_e = ntohs(sock_in_e->sin_port);
304 	}
305 
306 	if (ip_match && (port_e == port) &&
307 	    (np->np_network_transport == network_transport))
308 		return true;
309 
310 	return false;
311 }
312 
313 /*
314  * Called with mutex np_lock held
315  */
316 static struct iscsi_np *iscsit_get_np(
317 	struct sockaddr_storage *sockaddr,
318 	int network_transport)
319 {
320 	struct iscsi_np *np;
321 	bool match;
322 
323 	list_for_each_entry(np, &g_np_list, np_list) {
324 		spin_lock_bh(&np->np_thread_lock);
325 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
326 			spin_unlock_bh(&np->np_thread_lock);
327 			continue;
328 		}
329 
330 		match = iscsit_check_np_match(sockaddr, np, network_transport);
331 		if (match) {
332 			/*
333 			 * Increment the np_exports reference count now to
334 			 * prevent iscsit_del_np() below from being called
335 			 * while iscsi_tpg_add_network_portal() is called.
336 			 */
337 			np->np_exports++;
338 			spin_unlock_bh(&np->np_thread_lock);
339 			return np;
340 		}
341 		spin_unlock_bh(&np->np_thread_lock);
342 	}
343 
344 	return NULL;
345 }
346 
347 struct iscsi_np *iscsit_add_np(
348 	struct sockaddr_storage *sockaddr,
349 	int network_transport)
350 {
351 	struct iscsi_np *np;
352 	int ret;
353 
354 	mutex_lock(&np_lock);
355 
356 	/*
357 	 * Locate the existing struct iscsi_np if already active..
358 	 */
359 	np = iscsit_get_np(sockaddr, network_transport);
360 	if (np) {
361 		mutex_unlock(&np_lock);
362 		return np;
363 	}
364 
365 	np = kzalloc(sizeof(struct iscsi_np), GFP_KERNEL);
366 	if (!np) {
367 		pr_err("Unable to allocate memory for struct iscsi_np\n");
368 		mutex_unlock(&np_lock);
369 		return ERR_PTR(-ENOMEM);
370 	}
371 
372 	np->np_flags |= NPF_IP_NETWORK;
373 	np->np_network_transport = network_transport;
374 	spin_lock_init(&np->np_thread_lock);
375 	init_completion(&np->np_restart_comp);
376 	INIT_LIST_HEAD(&np->np_list);
377 
378 	ret = iscsi_target_setup_login_socket(np, sockaddr);
379 	if (ret != 0) {
380 		kfree(np);
381 		mutex_unlock(&np_lock);
382 		return ERR_PTR(ret);
383 	}
384 
385 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
386 	if (IS_ERR(np->np_thread)) {
387 		pr_err("Unable to create kthread: iscsi_np\n");
388 		ret = PTR_ERR(np->np_thread);
389 		kfree(np);
390 		mutex_unlock(&np_lock);
391 		return ERR_PTR(ret);
392 	}
393 	/*
394 	 * Increment the np_exports reference count now to prevent
395 	 * iscsit_del_np() below from being run while a new call to
396 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
397 	 * active.  We don't need to hold np->np_thread_lock at this
398 	 * point because iscsi_np has not been added to g_np_list yet.
399 	 */
400 	np->np_exports = 1;
401 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
402 
403 	list_add_tail(&np->np_list, &g_np_list);
404 	mutex_unlock(&np_lock);
405 
406 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
407 		&np->np_sockaddr, np->np_transport->name);
408 
409 	return np;
410 }
411 
412 int iscsit_reset_np_thread(
413 	struct iscsi_np *np,
414 	struct iscsi_tpg_np *tpg_np,
415 	struct iscsi_portal_group *tpg,
416 	bool shutdown)
417 {
418 	spin_lock_bh(&np->np_thread_lock);
419 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
420 		spin_unlock_bh(&np->np_thread_lock);
421 		return 0;
422 	}
423 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
424 
425 	if (np->np_thread) {
426 		spin_unlock_bh(&np->np_thread_lock);
427 		send_sig(SIGINT, np->np_thread, 1);
428 		wait_for_completion(&np->np_restart_comp);
429 		spin_lock_bh(&np->np_thread_lock);
430 	}
431 	spin_unlock_bh(&np->np_thread_lock);
432 
433 	if (tpg_np && shutdown) {
434 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
435 
436 		wait_for_completion(&tpg_np->tpg_np_comp);
437 	}
438 
439 	return 0;
440 }
441 
442 static void iscsit_free_np(struct iscsi_np *np)
443 {
444 	if (np->np_socket)
445 		sock_release(np->np_socket);
446 }
447 
448 int iscsit_del_np(struct iscsi_np *np)
449 {
450 	spin_lock_bh(&np->np_thread_lock);
451 	np->np_exports--;
452 	if (np->np_exports) {
453 		np->enabled = true;
454 		spin_unlock_bh(&np->np_thread_lock);
455 		return 0;
456 	}
457 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
458 	spin_unlock_bh(&np->np_thread_lock);
459 
460 	if (np->np_thread) {
461 		/*
462 		 * We need to send the signal to wakeup Linux/Net
463 		 * which may be sleeping in sock_accept()..
464 		 */
465 		send_sig(SIGINT, np->np_thread, 1);
466 		kthread_stop(np->np_thread);
467 		np->np_thread = NULL;
468 	}
469 
470 	np->np_transport->iscsit_free_np(np);
471 
472 	mutex_lock(&np_lock);
473 	list_del(&np->np_list);
474 	mutex_unlock(&np_lock);
475 
476 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
477 		&np->np_sockaddr, np->np_transport->name);
478 
479 	iscsit_put_transport(np->np_transport);
480 	kfree(np);
481 	return 0;
482 }
483 
484 static void iscsit_get_rx_pdu(struct iscsi_conn *);
485 
486 int iscsit_queue_rsp(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
487 {
488 	iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
489 	return 0;
490 }
491 EXPORT_SYMBOL(iscsit_queue_rsp);
492 
493 void iscsit_aborted_task(struct iscsi_conn *conn, struct iscsi_cmd *cmd)
494 {
495 	bool scsi_cmd = (cmd->iscsi_opcode == ISCSI_OP_SCSI_CMD);
496 
497 	spin_lock_bh(&conn->cmd_lock);
498 	if (!list_empty(&cmd->i_conn_node) &&
499 	    !(cmd->se_cmd.transport_state & CMD_T_FABRIC_STOP))
500 		list_del_init(&cmd->i_conn_node);
501 	spin_unlock_bh(&conn->cmd_lock);
502 
503 	__iscsit_free_cmd(cmd, scsi_cmd, true);
504 }
505 EXPORT_SYMBOL(iscsit_aborted_task);
506 
507 static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
508 				      u32, u32, u8 *, u8 *);
509 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *);
510 
511 static int
512 iscsit_xmit_nondatain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
513 			  const void *data_buf, u32 data_buf_len)
514 {
515 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
516 	struct kvec *iov;
517 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
518 	int ret;
519 
520 	iov = &cmd->iov_misc[0];
521 	iov[niov].iov_base	= cmd->pdu;
522 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
523 
524 	if (conn->conn_ops->HeaderDigest) {
525 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
526 
527 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
528 					  ISCSI_HDR_LEN, 0, NULL,
529 					  (u8 *)header_digest);
530 
531 		iov[0].iov_len += ISCSI_CRC_LEN;
532 		tx_size += ISCSI_CRC_LEN;
533 		pr_debug("Attaching CRC32C HeaderDigest"
534 			 " to opcode 0x%x 0x%08x\n",
535 			 hdr->opcode, *header_digest);
536 	}
537 
538 	if (data_buf_len) {
539 		u32 padding = ((-data_buf_len) & 3);
540 
541 		iov[niov].iov_base	= (void *)data_buf;
542 		iov[niov++].iov_len	= data_buf_len;
543 		tx_size += data_buf_len;
544 
545 		if (padding != 0) {
546 			iov[niov].iov_base = &cmd->pad_bytes;
547 			iov[niov++].iov_len = padding;
548 			tx_size += padding;
549 			pr_debug("Attaching %u additional"
550 				 " padding bytes.\n", padding);
551 		}
552 
553 		if (conn->conn_ops->DataDigest) {
554 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
555 						  data_buf, data_buf_len,
556 						  padding,
557 						  (u8 *)&cmd->pad_bytes,
558 						  (u8 *)&cmd->data_crc);
559 
560 			iov[niov].iov_base = &cmd->data_crc;
561 			iov[niov++].iov_len = ISCSI_CRC_LEN;
562 			tx_size += ISCSI_CRC_LEN;
563 			pr_debug("Attached DataDigest for %u"
564 				 " bytes opcode 0x%x, CRC 0x%08x\n",
565 				 data_buf_len, hdr->opcode, cmd->data_crc);
566 		}
567 	}
568 
569 	cmd->iov_misc_count = niov;
570 	cmd->tx_size = tx_size;
571 
572 	ret = iscsit_send_tx_data(cmd, conn, 1);
573 	if (ret < 0) {
574 		iscsit_tx_thread_wait_for_tcp(conn);
575 		return ret;
576 	}
577 
578 	return 0;
579 }
580 
581 static int iscsit_map_iovec(struct iscsi_cmd *, struct kvec *, u32, u32);
582 static void iscsit_unmap_iovec(struct iscsi_cmd *);
583 static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsi_cmd *,
584 				    u32, u32, u32, u8 *);
585 static int
586 iscsit_xmit_datain_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
587 		       const struct iscsi_datain *datain)
588 {
589 	struct kvec *iov;
590 	u32 iov_count = 0, tx_size = 0;
591 	int ret, iov_ret;
592 
593 	iov = &cmd->iov_data[0];
594 	iov[iov_count].iov_base	= cmd->pdu;
595 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
596 	tx_size += ISCSI_HDR_LEN;
597 
598 	if (conn->conn_ops->HeaderDigest) {
599 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
600 
601 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
602 					  ISCSI_HDR_LEN, 0, NULL,
603 					  (u8 *)header_digest);
604 
605 		iov[0].iov_len += ISCSI_CRC_LEN;
606 		tx_size += ISCSI_CRC_LEN;
607 
608 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
609 			 *header_digest);
610 	}
611 
612 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[1],
613 				   datain->offset, datain->length);
614 	if (iov_ret < 0)
615 		return -1;
616 
617 	iov_count += iov_ret;
618 	tx_size += datain->length;
619 
620 	cmd->padding = ((-datain->length) & 3);
621 	if (cmd->padding) {
622 		iov[iov_count].iov_base		= cmd->pad_bytes;
623 		iov[iov_count++].iov_len	= cmd->padding;
624 		tx_size += cmd->padding;
625 
626 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
627 	}
628 
629 	if (conn->conn_ops->DataDigest) {
630 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
631 							 cmd, datain->offset,
632 							 datain->length,
633 							 cmd->padding,
634 							 cmd->pad_bytes);
635 
636 		iov[iov_count].iov_base	= &cmd->data_crc;
637 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
638 		tx_size += ISCSI_CRC_LEN;
639 
640 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
641 			 datain->length + cmd->padding, cmd->data_crc);
642 	}
643 
644 	cmd->iov_data_count = iov_count;
645 	cmd->tx_size = tx_size;
646 
647 	ret = iscsit_fe_sendpage_sg(cmd, conn);
648 
649 	iscsit_unmap_iovec(cmd);
650 
651 	if (ret < 0) {
652 		iscsit_tx_thread_wait_for_tcp(conn);
653 		return ret;
654 	}
655 
656 	return 0;
657 }
658 
659 static int iscsit_xmit_pdu(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
660 			   struct iscsi_datain_req *dr, const void *buf,
661 			   u32 buf_len)
662 {
663 	if (dr)
664 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
665 	else
666 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
667 }
668 
669 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsi_conn *conn)
670 {
671 	return TARGET_PROT_NORMAL;
672 }
673 
674 static struct iscsit_transport iscsi_target_transport = {
675 	.name			= "iSCSI/TCP",
676 	.transport_type		= ISCSI_TCP,
677 	.rdma_shutdown		= false,
678 	.owner			= NULL,
679 	.iscsit_setup_np	= iscsit_setup_np,
680 	.iscsit_accept_np	= iscsit_accept_np,
681 	.iscsit_free_np		= iscsit_free_np,
682 	.iscsit_get_login_rx	= iscsit_get_login_rx,
683 	.iscsit_put_login_tx	= iscsit_put_login_tx,
684 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
685 	.iscsit_immediate_queue	= iscsit_immediate_queue,
686 	.iscsit_response_queue	= iscsit_response_queue,
687 	.iscsit_queue_data_in	= iscsit_queue_rsp,
688 	.iscsit_queue_status	= iscsit_queue_rsp,
689 	.iscsit_aborted_task	= iscsit_aborted_task,
690 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
691 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
692 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
693 };
694 
695 static int __init iscsi_target_init_module(void)
696 {
697 	int ret = 0, size;
698 
699 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
700 
701 	iscsit_global = kzalloc(sizeof(struct iscsit_global), GFP_KERNEL);
702 	if (!iscsit_global) {
703 		pr_err("Unable to allocate memory for iscsit_global\n");
704 		return -1;
705 	}
706 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
707 	mutex_init(&auth_id_lock);
708 	spin_lock_init(&sess_idr_lock);
709 	idr_init(&tiqn_idr);
710 	idr_init(&sess_idr);
711 
712 	ret = target_register_template(&iscsi_ops);
713 	if (ret)
714 		goto out;
715 
716 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
717 	iscsit_global->ts_bitmap = vzalloc(size);
718 	if (!iscsit_global->ts_bitmap) {
719 		pr_err("Unable to allocate iscsit_global->ts_bitmap\n");
720 		goto configfs_out;
721 	}
722 
723 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
724 			sizeof(struct iscsi_queue_req),
725 			__alignof__(struct iscsi_queue_req), 0, NULL);
726 	if (!lio_qr_cache) {
727 		pr_err("nable to kmem_cache_create() for"
728 				" lio_qr_cache\n");
729 		goto bitmap_out;
730 	}
731 
732 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
733 			sizeof(struct iscsi_datain_req),
734 			__alignof__(struct iscsi_datain_req), 0, NULL);
735 	if (!lio_dr_cache) {
736 		pr_err("Unable to kmem_cache_create() for"
737 				" lio_dr_cache\n");
738 		goto qr_out;
739 	}
740 
741 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
742 			sizeof(struct iscsi_ooo_cmdsn),
743 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
744 	if (!lio_ooo_cache) {
745 		pr_err("Unable to kmem_cache_create() for"
746 				" lio_ooo_cache\n");
747 		goto dr_out;
748 	}
749 
750 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
751 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
752 			0, NULL);
753 	if (!lio_r2t_cache) {
754 		pr_err("Unable to kmem_cache_create() for"
755 				" lio_r2t_cache\n");
756 		goto ooo_out;
757 	}
758 
759 	iscsit_register_transport(&iscsi_target_transport);
760 
761 	if (iscsit_load_discovery_tpg() < 0)
762 		goto r2t_out;
763 
764 	return ret;
765 r2t_out:
766 	iscsit_unregister_transport(&iscsi_target_transport);
767 	kmem_cache_destroy(lio_r2t_cache);
768 ooo_out:
769 	kmem_cache_destroy(lio_ooo_cache);
770 dr_out:
771 	kmem_cache_destroy(lio_dr_cache);
772 qr_out:
773 	kmem_cache_destroy(lio_qr_cache);
774 bitmap_out:
775 	vfree(iscsit_global->ts_bitmap);
776 configfs_out:
777 	/* XXX: this probably wants it to be it's own unwind step.. */
778 	if (iscsit_global->discovery_tpg)
779 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
780 	target_unregister_template(&iscsi_ops);
781 out:
782 	kfree(iscsit_global);
783 	return -ENOMEM;
784 }
785 
786 static void __exit iscsi_target_cleanup_module(void)
787 {
788 	iscsit_release_discovery_tpg();
789 	iscsit_unregister_transport(&iscsi_target_transport);
790 	kmem_cache_destroy(lio_qr_cache);
791 	kmem_cache_destroy(lio_dr_cache);
792 	kmem_cache_destroy(lio_ooo_cache);
793 	kmem_cache_destroy(lio_r2t_cache);
794 
795 	/*
796 	 * Shutdown discovery sessions and disable discovery TPG
797 	 */
798 	if (iscsit_global->discovery_tpg)
799 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
800 
801 	target_unregister_template(&iscsi_ops);
802 
803 	vfree(iscsit_global->ts_bitmap);
804 	kfree(iscsit_global);
805 }
806 
807 int iscsit_add_reject(
808 	struct iscsi_conn *conn,
809 	u8 reason,
810 	unsigned char *buf)
811 {
812 	struct iscsi_cmd *cmd;
813 
814 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
815 	if (!cmd)
816 		return -1;
817 
818 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
819 	cmd->reject_reason = reason;
820 
821 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
822 	if (!cmd->buf_ptr) {
823 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
824 		iscsit_free_cmd(cmd, false);
825 		return -1;
826 	}
827 
828 	spin_lock_bh(&conn->cmd_lock);
829 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
830 	spin_unlock_bh(&conn->cmd_lock);
831 
832 	cmd->i_state = ISTATE_SEND_REJECT;
833 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
834 
835 	return -1;
836 }
837 EXPORT_SYMBOL(iscsit_add_reject);
838 
839 static int iscsit_add_reject_from_cmd(
840 	struct iscsi_cmd *cmd,
841 	u8 reason,
842 	bool add_to_conn,
843 	unsigned char *buf)
844 {
845 	struct iscsi_conn *conn;
846 
847 	if (!cmd->conn) {
848 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
849 				cmd->init_task_tag);
850 		return -1;
851 	}
852 	conn = cmd->conn;
853 
854 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
855 	cmd->reject_reason = reason;
856 
857 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
858 	if (!cmd->buf_ptr) {
859 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
860 		iscsit_free_cmd(cmd, false);
861 		return -1;
862 	}
863 
864 	if (add_to_conn) {
865 		spin_lock_bh(&conn->cmd_lock);
866 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
867 		spin_unlock_bh(&conn->cmd_lock);
868 	}
869 
870 	cmd->i_state = ISTATE_SEND_REJECT;
871 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
872 	/*
873 	 * Perform the kref_put now if se_cmd has already been setup by
874 	 * scsit_setup_scsi_cmd()
875 	 */
876 	if (cmd->se_cmd.se_tfo != NULL) {
877 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
878 		target_put_sess_cmd(&cmd->se_cmd);
879 	}
880 	return -1;
881 }
882 
883 static int iscsit_add_reject_cmd(struct iscsi_cmd *cmd, u8 reason,
884 				 unsigned char *buf)
885 {
886 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
887 }
888 
889 int iscsit_reject_cmd(struct iscsi_cmd *cmd, u8 reason, unsigned char *buf)
890 {
891 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
892 }
893 EXPORT_SYMBOL(iscsit_reject_cmd);
894 
895 /*
896  * Map some portion of the allocated scatterlist to an iovec, suitable for
897  * kernel sockets to copy data in/out.
898  */
899 static int iscsit_map_iovec(
900 	struct iscsi_cmd *cmd,
901 	struct kvec *iov,
902 	u32 data_offset,
903 	u32 data_length)
904 {
905 	u32 i = 0;
906 	struct scatterlist *sg;
907 	unsigned int page_off;
908 
909 	/*
910 	 * We know each entry in t_data_sg contains a page.
911 	 */
912 	u32 ent = data_offset / PAGE_SIZE;
913 
914 	if (ent >= cmd->se_cmd.t_data_nents) {
915 		pr_err("Initial page entry out-of-bounds\n");
916 		return -1;
917 	}
918 
919 	sg = &cmd->se_cmd.t_data_sg[ent];
920 	page_off = (data_offset % PAGE_SIZE);
921 
922 	cmd->first_data_sg = sg;
923 	cmd->first_data_sg_off = page_off;
924 
925 	while (data_length) {
926 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
927 
928 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
929 		iov[i].iov_len = cur_len;
930 
931 		data_length -= cur_len;
932 		page_off = 0;
933 		sg = sg_next(sg);
934 		i++;
935 	}
936 
937 	cmd->kmapped_nents = i;
938 
939 	return i;
940 }
941 
942 static void iscsit_unmap_iovec(struct iscsi_cmd *cmd)
943 {
944 	u32 i;
945 	struct scatterlist *sg;
946 
947 	sg = cmd->first_data_sg;
948 
949 	for (i = 0; i < cmd->kmapped_nents; i++)
950 		kunmap(sg_page(&sg[i]));
951 }
952 
953 static void iscsit_ack_from_expstatsn(struct iscsi_conn *conn, u32 exp_statsn)
954 {
955 	LIST_HEAD(ack_list);
956 	struct iscsi_cmd *cmd, *cmd_p;
957 
958 	conn->exp_statsn = exp_statsn;
959 
960 	if (conn->sess->sess_ops->RDMAExtensions)
961 		return;
962 
963 	spin_lock_bh(&conn->cmd_lock);
964 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
965 		spin_lock(&cmd->istate_lock);
966 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
967 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
968 			cmd->i_state = ISTATE_REMOVE;
969 			spin_unlock(&cmd->istate_lock);
970 			list_move_tail(&cmd->i_conn_node, &ack_list);
971 			continue;
972 		}
973 		spin_unlock(&cmd->istate_lock);
974 	}
975 	spin_unlock_bh(&conn->cmd_lock);
976 
977 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
978 		list_del_init(&cmd->i_conn_node);
979 		iscsit_free_cmd(cmd, false);
980 	}
981 }
982 
983 static int iscsit_allocate_iovecs(struct iscsi_cmd *cmd)
984 {
985 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
986 
987 	iov_count += ISCSI_IOV_DATA_BUFFER;
988 
989 	cmd->iov_data = kzalloc(iov_count * sizeof(struct kvec), GFP_KERNEL);
990 	if (!cmd->iov_data) {
991 		pr_err("Unable to allocate cmd->iov_data\n");
992 		return -ENOMEM;
993 	}
994 
995 	cmd->orig_iov_data_count = iov_count;
996 	return 0;
997 }
998 
999 int iscsit_setup_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1000 			  unsigned char *buf)
1001 {
1002 	int data_direction, payload_length;
1003 	struct iscsi_scsi_req *hdr;
1004 	int iscsi_task_attr;
1005 	int sam_task_attr;
1006 
1007 	atomic_long_inc(&conn->sess->cmd_pdus);
1008 
1009 	hdr			= (struct iscsi_scsi_req *) buf;
1010 	payload_length		= ntoh24(hdr->dlength);
1011 
1012 	/* FIXME; Add checks for AdditionalHeaderSegment */
1013 
1014 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1015 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1016 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1017 				" not set. Bad iSCSI Initiator.\n");
1018 		return iscsit_add_reject_cmd(cmd,
1019 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1020 	}
1021 
1022 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1023 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1024 		/*
1025 		 * From RFC-3720 Section 10.3.1:
1026 		 *
1027 		 * "Either or both of R and W MAY be 1 when either the
1028 		 *  Expected Data Transfer Length and/or Bidirectional Read
1029 		 *  Expected Data Transfer Length are 0"
1030 		 *
1031 		 * For this case, go ahead and clear the unnecssary bits
1032 		 * to avoid any confusion with ->data_direction.
1033 		 */
1034 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1035 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1036 
1037 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1038 			" set when Expected Data Transfer Length is 0 for"
1039 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1040 	}
1041 
1042 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1043 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1044 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1045 			" MUST be set if Expected Data Transfer Length is not 0."
1046 			" Bad iSCSI Initiator\n");
1047 		return iscsit_add_reject_cmd(cmd,
1048 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1049 	}
1050 
1051 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1052 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1053 		pr_err("Bidirectional operations not supported!\n");
1054 		return iscsit_add_reject_cmd(cmd,
1055 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1056 	}
1057 
1058 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1059 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1060 				" Scsi Command PDU.\n");
1061 		return iscsit_add_reject_cmd(cmd,
1062 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1063 	}
1064 
1065 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1066 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1067 			" protocol error.\n", payload_length);
1068 		return iscsit_add_reject_cmd(cmd,
1069 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1070 	}
1071 
1072 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1073 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1074 		pr_err("Expected Data Transfer Length and Length of"
1075 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1076 			" bit is not set protocol error\n");
1077 		return iscsit_add_reject_cmd(cmd,
1078 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1079 	}
1080 
1081 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1082 		pr_err("DataSegmentLength: %u is greater than"
1083 			" EDTL: %u, protocol error.\n", payload_length,
1084 				hdr->data_length);
1085 		return iscsit_add_reject_cmd(cmd,
1086 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1087 	}
1088 
1089 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1090 		pr_err("DataSegmentLength: %u is greater than"
1091 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1092 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1093 		return iscsit_add_reject_cmd(cmd,
1094 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1095 	}
1096 
1097 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1098 		pr_err("DataSegmentLength: %u is greater than"
1099 			" FirstBurstLength: %u, protocol error.\n",
1100 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1101 		return iscsit_add_reject_cmd(cmd,
1102 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1103 	}
1104 
1105 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1106 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1107 			  DMA_NONE;
1108 
1109 	cmd->data_direction = data_direction;
1110 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1111 	/*
1112 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1113 	 */
1114 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1115 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1116 		sam_task_attr = TCM_SIMPLE_TAG;
1117 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1118 		sam_task_attr = TCM_ORDERED_TAG;
1119 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1120 		sam_task_attr = TCM_HEAD_TAG;
1121 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1122 		sam_task_attr = TCM_ACA_TAG;
1123 	else {
1124 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1125 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1126 		sam_task_attr = TCM_SIMPLE_TAG;
1127 	}
1128 
1129 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1130 	cmd->i_state		= ISTATE_NEW_CMD;
1131 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1132 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1133 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1134 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1135 	if (cmd->unsolicited_data)
1136 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1137 
1138 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1139 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1140 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1141 	else
1142 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1143 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1144 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1145 	cmd->first_burst_len	= payload_length;
1146 
1147 	if (!conn->sess->sess_ops->RDMAExtensions &&
1148 	     cmd->data_direction == DMA_FROM_DEVICE) {
1149 		struct iscsi_datain_req *dr;
1150 
1151 		dr = iscsit_allocate_datain_req();
1152 		if (!dr)
1153 			return iscsit_add_reject_cmd(cmd,
1154 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1155 
1156 		iscsit_attach_datain_req(cmd, dr);
1157 	}
1158 
1159 	/*
1160 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1161 	 */
1162 	transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
1163 			conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1164 			cmd->data_direction, sam_task_attr,
1165 			cmd->sense_buffer + 2);
1166 
1167 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1168 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1169 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1170 		conn->cid);
1171 
1172 	target_get_sess_cmd(&cmd->se_cmd, true);
1173 
1174 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd,
1175 						     scsilun_to_int(&hdr->lun));
1176 	if (cmd->sense_reason)
1177 		goto attach_cmd;
1178 
1179 	/* only used for printks or comparing with ->ref_task_tag */
1180 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1181 	cmd->sense_reason = target_setup_cmd_from_cdb(&cmd->se_cmd, hdr->cdb);
1182 	if (cmd->sense_reason) {
1183 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1184 			return iscsit_add_reject_cmd(cmd,
1185 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1186 		}
1187 
1188 		goto attach_cmd;
1189 	}
1190 
1191 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1192 		return iscsit_add_reject_cmd(cmd,
1193 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1194 	}
1195 
1196 attach_cmd:
1197 	spin_lock_bh(&conn->cmd_lock);
1198 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1199 	spin_unlock_bh(&conn->cmd_lock);
1200 	/*
1201 	 * Check if we need to delay processing because of ALUA
1202 	 * Active/NonOptimized primary access state..
1203 	 */
1204 	core_alua_check_nonop_delay(&cmd->se_cmd);
1205 
1206 	return 0;
1207 }
1208 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1209 
1210 void iscsit_set_unsoliticed_dataout(struct iscsi_cmd *cmd)
1211 {
1212 	iscsit_set_dataout_sequence_values(cmd);
1213 
1214 	spin_lock_bh(&cmd->dataout_timeout_lock);
1215 	iscsit_start_dataout_timer(cmd, cmd->conn);
1216 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1217 }
1218 EXPORT_SYMBOL(iscsit_set_unsoliticed_dataout);
1219 
1220 int iscsit_process_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1221 			    struct iscsi_scsi_req *hdr)
1222 {
1223 	int cmdsn_ret = 0;
1224 	/*
1225 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1226 	 * the Immediate Bit is not set, and no Immediate
1227 	 * Data is attached.
1228 	 *
1229 	 * A PDU/CmdSN carrying Immediate Data can only
1230 	 * be processed after the DataCRC has passed.
1231 	 * If the DataCRC fails, the CmdSN MUST NOT
1232 	 * be acknowledged. (See below)
1233 	 */
1234 	if (!cmd->immediate_data) {
1235 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1236 					(unsigned char *)hdr, hdr->cmdsn);
1237 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1238 			return -1;
1239 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1240 			target_put_sess_cmd(&cmd->se_cmd);
1241 			return 0;
1242 		}
1243 	}
1244 
1245 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1246 
1247 	/*
1248 	 * If no Immediate Data is attached, it's OK to return now.
1249 	 */
1250 	if (!cmd->immediate_data) {
1251 		if (!cmd->sense_reason && cmd->unsolicited_data)
1252 			iscsit_set_unsoliticed_dataout(cmd);
1253 		if (!cmd->sense_reason)
1254 			return 0;
1255 
1256 		target_put_sess_cmd(&cmd->se_cmd);
1257 		return 0;
1258 	}
1259 
1260 	/*
1261 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1262 	 * execution.  These exceptions are processed in CmdSN order using
1263 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1264 	 */
1265 	if (cmd->sense_reason) {
1266 		if (cmd->reject_reason)
1267 			return 0;
1268 
1269 		return 1;
1270 	}
1271 	/*
1272 	 * Call directly into transport_generic_new_cmd() to perform
1273 	 * the backend memory allocation.
1274 	 */
1275 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1276 	if (cmd->sense_reason)
1277 		return 1;
1278 
1279 	return 0;
1280 }
1281 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1282 
1283 static int
1284 iscsit_get_immediate_data(struct iscsi_cmd *cmd, struct iscsi_scsi_req *hdr,
1285 			  bool dump_payload)
1286 {
1287 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1288 	/*
1289 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1290 	 */
1291 	if (dump_payload)
1292 		goto after_immediate_data;
1293 
1294 	immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1295 					cmd->first_burst_len);
1296 after_immediate_data:
1297 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1298 		/*
1299 		 * A PDU/CmdSN carrying Immediate Data passed
1300 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1301 		 * Immediate Bit is not set.
1302 		 */
1303 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1304 					(unsigned char *)hdr, hdr->cmdsn);
1305 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1306 			return -1;
1307 
1308 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1309 			int rc;
1310 
1311 			rc = iscsit_dump_data_payload(cmd->conn,
1312 						      cmd->first_burst_len, 1);
1313 			target_put_sess_cmd(&cmd->se_cmd);
1314 			return rc;
1315 		} else if (cmd->unsolicited_data)
1316 			iscsit_set_unsoliticed_dataout(cmd);
1317 
1318 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1319 		/*
1320 		 * Immediate Data failed DataCRC and ERL>=1,
1321 		 * silently drop this PDU and let the initiator
1322 		 * plug the CmdSN gap.
1323 		 *
1324 		 * FIXME: Send Unsolicited NOPIN with reserved
1325 		 * TTT here to help the initiator figure out
1326 		 * the missing CmdSN, although they should be
1327 		 * intelligent enough to determine the missing
1328 		 * CmdSN and issue a retry to plug the sequence.
1329 		 */
1330 		cmd->i_state = ISTATE_REMOVE;
1331 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1332 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1333 		return -1;
1334 
1335 	return 0;
1336 }
1337 
1338 static int
1339 iscsit_handle_scsi_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1340 			   unsigned char *buf)
1341 {
1342 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1343 	int rc, immed_data;
1344 	bool dump_payload = false;
1345 
1346 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1347 	if (rc < 0)
1348 		return 0;
1349 	/*
1350 	 * Allocation iovecs needed for struct socket operations for
1351 	 * traditional iSCSI block I/O.
1352 	 */
1353 	if (iscsit_allocate_iovecs(cmd) < 0) {
1354 		return iscsit_reject_cmd(cmd,
1355 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1356 	}
1357 	immed_data = cmd->immediate_data;
1358 
1359 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1360 	if (rc < 0)
1361 		return rc;
1362 	else if (rc > 0)
1363 		dump_payload = true;
1364 
1365 	if (!immed_data)
1366 		return 0;
1367 
1368 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1369 }
1370 
1371 static u32 iscsit_do_crypto_hash_sg(
1372 	struct ahash_request *hash,
1373 	struct iscsi_cmd *cmd,
1374 	u32 data_offset,
1375 	u32 data_length,
1376 	u32 padding,
1377 	u8 *pad_bytes)
1378 {
1379 	u32 data_crc;
1380 	struct scatterlist *sg;
1381 	unsigned int page_off;
1382 
1383 	crypto_ahash_init(hash);
1384 
1385 	sg = cmd->first_data_sg;
1386 	page_off = cmd->first_data_sg_off;
1387 
1388 	while (data_length) {
1389 		u32 cur_len = min_t(u32, data_length, (sg->length - page_off));
1390 
1391 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1392 		crypto_ahash_update(hash);
1393 
1394 		data_length -= cur_len;
1395 		page_off = 0;
1396 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1397 		sg = sg_next(sg);
1398 	}
1399 
1400 	if (padding) {
1401 		struct scatterlist pad_sg;
1402 
1403 		sg_init_one(&pad_sg, pad_bytes, padding);
1404 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1405 					padding);
1406 		crypto_ahash_finup(hash);
1407 	} else {
1408 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1409 		crypto_ahash_final(hash);
1410 	}
1411 
1412 	return data_crc;
1413 }
1414 
1415 static void iscsit_do_crypto_hash_buf(
1416 	struct ahash_request *hash,
1417 	const void *buf,
1418 	u32 payload_length,
1419 	u32 padding,
1420 	u8 *pad_bytes,
1421 	u8 *data_crc)
1422 {
1423 	struct scatterlist sg[2];
1424 
1425 	sg_init_table(sg, ARRAY_SIZE(sg));
1426 	sg_set_buf(sg, buf, payload_length);
1427 	sg_set_buf(sg + 1, pad_bytes, padding);
1428 
1429 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1430 
1431 	crypto_ahash_digest(hash);
1432 }
1433 
1434 int
1435 __iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1436 			   struct iscsi_cmd *cmd, u32 payload_length,
1437 			   bool *success)
1438 {
1439 	struct iscsi_data *hdr = buf;
1440 	struct se_cmd *se_cmd;
1441 	int rc;
1442 
1443 	/* iSCSI write */
1444 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1445 
1446 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1447 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1448 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1449 		payload_length, conn->cid);
1450 
1451 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1452 		pr_err("Command ITT: 0x%08x received DataOUT after"
1453 			" last DataOUT received, dumping payload\n",
1454 			cmd->init_task_tag);
1455 		return iscsit_dump_data_payload(conn, payload_length, 1);
1456 	}
1457 
1458 	if (cmd->data_direction != DMA_TO_DEVICE) {
1459 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1460 			" NON-WRITE command.\n", cmd->init_task_tag);
1461 		return iscsit_dump_data_payload(conn, payload_length, 1);
1462 	}
1463 	se_cmd = &cmd->se_cmd;
1464 	iscsit_mod_dataout_timer(cmd);
1465 
1466 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1467 		pr_err("DataOut Offset: %u, Length %u greater than"
1468 			" iSCSI Command EDTL %u, protocol error.\n",
1469 			hdr->offset, payload_length, cmd->se_cmd.data_length);
1470 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1471 	}
1472 
1473 	if (cmd->unsolicited_data) {
1474 		int dump_unsolicited_data = 0;
1475 
1476 		if (conn->sess->sess_ops->InitialR2T) {
1477 			pr_err("Received unexpected unsolicited data"
1478 				" while InitialR2T=Yes, protocol error.\n");
1479 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1480 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1481 			return -1;
1482 		}
1483 		/*
1484 		 * Special case for dealing with Unsolicited DataOUT
1485 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1486 		 * failures;
1487 		 */
1488 
1489 		/* Something's amiss if we're not in WRITE_PENDING state... */
1490 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1491 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1492 			dump_unsolicited_data = 1;
1493 
1494 		if (dump_unsolicited_data) {
1495 			/*
1496 			 * Check if a delayed TASK_ABORTED status needs to
1497 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1498 			 * received with the unsolicited data out.
1499 			 */
1500 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1501 				iscsit_stop_dataout_timer(cmd);
1502 
1503 			transport_check_aborted_status(se_cmd,
1504 					(hdr->flags & ISCSI_FLAG_CMD_FINAL));
1505 			return iscsit_dump_data_payload(conn, payload_length, 1);
1506 		}
1507 	} else {
1508 		/*
1509 		 * For the normal solicited data path:
1510 		 *
1511 		 * Check for a delayed TASK_ABORTED status and dump any
1512 		 * incoming data out payload if one exists.  Also, when the
1513 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1514 		 * data out sequence, we decrement outstanding_r2ts.  Once
1515 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1516 		 * TASK_ABORTED status.
1517 		 */
1518 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1519 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1520 				if (--cmd->outstanding_r2ts < 1) {
1521 					iscsit_stop_dataout_timer(cmd);
1522 					transport_check_aborted_status(
1523 							se_cmd, 1);
1524 				}
1525 
1526 			return iscsit_dump_data_payload(conn, payload_length, 1);
1527 		}
1528 	}
1529 	/*
1530 	 * Perform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1531 	 * within-command recovery checks before receiving the payload.
1532 	 */
1533 	rc = iscsit_check_pre_dataout(cmd, buf);
1534 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1535 		return 0;
1536 	else if (rc == DATAOUT_CANNOT_RECOVER)
1537 		return -1;
1538 	*success = true;
1539 	return 0;
1540 }
1541 EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
1542 
1543 int
1544 iscsit_check_dataout_hdr(struct iscsi_conn *conn, void *buf,
1545 			 struct iscsi_cmd **out_cmd)
1546 {
1547 	struct iscsi_data *hdr = buf;
1548 	struct iscsi_cmd *cmd;
1549 	u32 payload_length = ntoh24(hdr->dlength);
1550 	int rc;
1551 	bool success = false;
1552 
1553 	if (!payload_length) {
1554 		pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
1555 		return 0;
1556 	}
1557 
1558 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1559 		pr_err_ratelimited("DataSegmentLength: %u is greater than"
1560 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1561 			conn->conn_ops->MaxXmitDataSegmentLength);
1562 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
1563 	}
1564 
1565 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
1566 	if (!cmd)
1567 		return 0;
1568 
1569 	rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
1570 
1571 	if (success)
1572 		*out_cmd = cmd;
1573 
1574 	return rc;
1575 }
1576 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1577 
1578 static int
1579 iscsit_get_dataout(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1580 		   struct iscsi_data *hdr)
1581 {
1582 	struct kvec *iov;
1583 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1584 	u32 payload_length = ntoh24(hdr->dlength);
1585 	int iov_ret, data_crc_failed = 0;
1586 
1587 	rx_size += payload_length;
1588 	iov = &cmd->iov_data[0];
1589 
1590 	iov_ret = iscsit_map_iovec(cmd, iov, be32_to_cpu(hdr->offset),
1591 				   payload_length);
1592 	if (iov_ret < 0)
1593 		return -1;
1594 
1595 	iov_count += iov_ret;
1596 
1597 	padding = ((-payload_length) & 3);
1598 	if (padding != 0) {
1599 		iov[iov_count].iov_base	= cmd->pad_bytes;
1600 		iov[iov_count++].iov_len = padding;
1601 		rx_size += padding;
1602 		pr_debug("Receiving %u padding bytes.\n", padding);
1603 	}
1604 
1605 	if (conn->conn_ops->DataDigest) {
1606 		iov[iov_count].iov_base = &checksum;
1607 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1608 		rx_size += ISCSI_CRC_LEN;
1609 	}
1610 
1611 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1612 
1613 	iscsit_unmap_iovec(cmd);
1614 
1615 	if (rx_got != rx_size)
1616 		return -1;
1617 
1618 	if (conn->conn_ops->DataDigest) {
1619 		u32 data_crc;
1620 
1621 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1622 						    be32_to_cpu(hdr->offset),
1623 						    payload_length, padding,
1624 						    cmd->pad_bytes);
1625 
1626 		if (checksum != data_crc) {
1627 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1628 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1629 				" does not match computed 0x%08x\n",
1630 				hdr->itt, hdr->offset, payload_length,
1631 				hdr->datasn, checksum, data_crc);
1632 			data_crc_failed = 1;
1633 		} else {
1634 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1635 				" %u bytes of Data Out\n", checksum,
1636 				payload_length);
1637 		}
1638 	}
1639 
1640 	return data_crc_failed;
1641 }
1642 
1643 int
1644 iscsit_check_dataout_payload(struct iscsi_cmd *cmd, struct iscsi_data *hdr,
1645 			     bool data_crc_failed)
1646 {
1647 	struct iscsi_conn *conn = cmd->conn;
1648 	int rc, ooo_cmdsn;
1649 	/*
1650 	 * Increment post receive data and CRC values or perform
1651 	 * within-command recovery.
1652 	 */
1653 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1654 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1655 		return 0;
1656 	else if (rc == DATAOUT_SEND_R2T) {
1657 		iscsit_set_dataout_sequence_values(cmd);
1658 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1659 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1660 		/*
1661 		 * Handle extra special case for out of order
1662 		 * Unsolicited Data Out.
1663 		 */
1664 		spin_lock_bh(&cmd->istate_lock);
1665 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1666 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1667 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1668 		spin_unlock_bh(&cmd->istate_lock);
1669 
1670 		iscsit_stop_dataout_timer(cmd);
1671 		if (ooo_cmdsn)
1672 			return 0;
1673 		target_execute_cmd(&cmd->se_cmd);
1674 		return 0;
1675 	} else /* DATAOUT_CANNOT_RECOVER */
1676 		return -1;
1677 
1678 	return 0;
1679 }
1680 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1681 
1682 static int iscsit_handle_data_out(struct iscsi_conn *conn, unsigned char *buf)
1683 {
1684 	struct iscsi_cmd *cmd = NULL;
1685 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1686 	int rc;
1687 	bool data_crc_failed = false;
1688 
1689 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1690 	if (rc < 0)
1691 		return 0;
1692 	else if (!cmd)
1693 		return 0;
1694 
1695 	rc = iscsit_get_dataout(conn, cmd, hdr);
1696 	if (rc < 0)
1697 		return rc;
1698 	else if (rc > 0)
1699 		data_crc_failed = true;
1700 
1701 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1702 }
1703 
1704 int iscsit_setup_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1705 			 struct iscsi_nopout *hdr)
1706 {
1707 	u32 payload_length = ntoh24(hdr->dlength);
1708 
1709 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1710 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1711 		if (!cmd)
1712 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1713 						 (unsigned char *)hdr);
1714 
1715 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1716 					 (unsigned char *)hdr);
1717 	}
1718 
1719 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1720 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1721 			" not set, protocol error.\n");
1722 		if (!cmd)
1723 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1724 						 (unsigned char *)hdr);
1725 
1726 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1727 					 (unsigned char *)hdr);
1728 	}
1729 
1730 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1731 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1732 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1733 			" error.\n", payload_length,
1734 			conn->conn_ops->MaxXmitDataSegmentLength);
1735 		if (!cmd)
1736 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1737 						 (unsigned char *)hdr);
1738 
1739 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1740 					 (unsigned char *)hdr);
1741 	}
1742 
1743 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1744 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1745 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1746 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1747 		payload_length);
1748 	/*
1749 	 * This is not a response to a Unsolicited NopIN, which means
1750 	 * it can either be a NOPOUT ping request (with a valid ITT),
1751 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1752 	 * Either way, make sure we allocate an struct iscsi_cmd, as both
1753 	 * can contain ping data.
1754 	 */
1755 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1756 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1757 		cmd->i_state		= ISTATE_SEND_NOPIN;
1758 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1759 						1 : 0);
1760 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1761 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1762 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1763 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1764 		cmd->data_direction	= DMA_NONE;
1765 	}
1766 
1767 	return 0;
1768 }
1769 EXPORT_SYMBOL(iscsit_setup_nop_out);
1770 
1771 int iscsit_process_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1772 			   struct iscsi_nopout *hdr)
1773 {
1774 	struct iscsi_cmd *cmd_p = NULL;
1775 	int cmdsn_ret = 0;
1776 	/*
1777 	 * Initiator is expecting a NopIN ping reply..
1778 	 */
1779 	if (hdr->itt != RESERVED_ITT) {
1780 		if (!cmd)
1781 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1782 						(unsigned char *)hdr);
1783 
1784 		spin_lock_bh(&conn->cmd_lock);
1785 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1786 		spin_unlock_bh(&conn->cmd_lock);
1787 
1788 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1789 
1790 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1791 			iscsit_add_cmd_to_response_queue(cmd, conn,
1792 							 cmd->i_state);
1793 			return 0;
1794 		}
1795 
1796 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1797 				(unsigned char *)hdr, hdr->cmdsn);
1798                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1799 			return 0;
1800 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1801 			return -1;
1802 
1803 		return 0;
1804 	}
1805 	/*
1806 	 * This was a response to a unsolicited NOPIN ping.
1807 	 */
1808 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1809 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1810 		if (!cmd_p)
1811 			return -EINVAL;
1812 
1813 		iscsit_stop_nopin_response_timer(conn);
1814 
1815 		cmd_p->i_state = ISTATE_REMOVE;
1816 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1817 
1818 		iscsit_start_nopin_timer(conn);
1819 		return 0;
1820 	}
1821 	/*
1822 	 * Otherwise, initiator is not expecting a NOPIN is response.
1823 	 * Just ignore for now.
1824 	 */
1825 
1826 	if (cmd)
1827 		iscsit_free_cmd(cmd, false);
1828 
1829         return 0;
1830 }
1831 EXPORT_SYMBOL(iscsit_process_nop_out);
1832 
1833 static int iscsit_handle_nop_out(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1834 				 unsigned char *buf)
1835 {
1836 	unsigned char *ping_data = NULL;
1837 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1838 	struct kvec *iov = NULL;
1839 	u32 payload_length = ntoh24(hdr->dlength);
1840 	int ret;
1841 
1842 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1843 	if (ret < 0)
1844 		return 0;
1845 	/*
1846 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1847 	 */
1848 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1849 		u32 checksum, data_crc, padding = 0;
1850 		int niov = 0, rx_got, rx_size = payload_length;
1851 
1852 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1853 		if (!ping_data) {
1854 			pr_err("Unable to allocate memory for"
1855 				" NOPOUT ping data.\n");
1856 			ret = -1;
1857 			goto out;
1858 		}
1859 
1860 		iov = &cmd->iov_misc[0];
1861 		iov[niov].iov_base	= ping_data;
1862 		iov[niov++].iov_len	= payload_length;
1863 
1864 		padding = ((-payload_length) & 3);
1865 		if (padding != 0) {
1866 			pr_debug("Receiving %u additional bytes"
1867 				" for padding.\n", padding);
1868 			iov[niov].iov_base	= &cmd->pad_bytes;
1869 			iov[niov++].iov_len	= padding;
1870 			rx_size += padding;
1871 		}
1872 		if (conn->conn_ops->DataDigest) {
1873 			iov[niov].iov_base	= &checksum;
1874 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1875 			rx_size += ISCSI_CRC_LEN;
1876 		}
1877 
1878 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1879 		if (rx_got != rx_size) {
1880 			ret = -1;
1881 			goto out;
1882 		}
1883 
1884 		if (conn->conn_ops->DataDigest) {
1885 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
1886 					ping_data, payload_length,
1887 					padding, cmd->pad_bytes,
1888 					(u8 *)&data_crc);
1889 
1890 			if (checksum != data_crc) {
1891 				pr_err("Ping data CRC32C DataDigest"
1892 				" 0x%08x does not match computed 0x%08x\n",
1893 					checksum, data_crc);
1894 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1895 					pr_err("Unable to recover from"
1896 					" NOPOUT Ping DataCRC failure while in"
1897 						" ERL=0.\n");
1898 					ret = -1;
1899 					goto out;
1900 				} else {
1901 					/*
1902 					 * Silently drop this PDU and let the
1903 					 * initiator plug the CmdSN gap.
1904 					 */
1905 					pr_debug("Dropping NOPOUT"
1906 					" Command CmdSN: 0x%08x due to"
1907 					" DataCRC error.\n", hdr->cmdsn);
1908 					ret = 0;
1909 					goto out;
1910 				}
1911 			} else {
1912 				pr_debug("Got CRC32C DataDigest"
1913 				" 0x%08x for %u bytes of ping data.\n",
1914 					checksum, payload_length);
1915 			}
1916 		}
1917 
1918 		ping_data[payload_length] = '\0';
1919 		/*
1920 		 * Attach ping data to struct iscsi_cmd->buf_ptr.
1921 		 */
1922 		cmd->buf_ptr = ping_data;
1923 		cmd->buf_ptr_size = payload_length;
1924 
1925 		pr_debug("Got %u bytes of NOPOUT ping"
1926 			" data.\n", payload_length);
1927 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1928 	}
1929 
1930 	return iscsit_process_nop_out(conn, cmd, hdr);
1931 out:
1932 	if (cmd)
1933 		iscsit_free_cmd(cmd, false);
1934 
1935 	kfree(ping_data);
1936 	return ret;
1937 }
1938 
1939 static enum tcm_tmreq_table iscsit_convert_tmf(u8 iscsi_tmf)
1940 {
1941 	switch (iscsi_tmf) {
1942 	case ISCSI_TM_FUNC_ABORT_TASK:
1943 		return TMR_ABORT_TASK;
1944 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1945 		return TMR_ABORT_TASK_SET;
1946 	case ISCSI_TM_FUNC_CLEAR_ACA:
1947 		return TMR_CLEAR_ACA;
1948 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1949 		return TMR_CLEAR_TASK_SET;
1950 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1951 		return TMR_LUN_RESET;
1952 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1953 		return TMR_TARGET_WARM_RESET;
1954 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1955 		return TMR_TARGET_COLD_RESET;
1956 	default:
1957 		return TMR_UNKNOWN;
1958 	}
1959 }
1960 
1961 int
1962 iscsit_handle_task_mgt_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
1963 			   unsigned char *buf)
1964 {
1965 	struct se_tmr_req *se_tmr;
1966 	struct iscsi_tmr_req *tmr_req;
1967 	struct iscsi_tm *hdr;
1968 	int out_of_order_cmdsn = 0, ret;
1969 	bool sess_ref = false;
1970 	u8 function, tcm_function = TMR_UNKNOWN;
1971 
1972 	hdr			= (struct iscsi_tm *) buf;
1973 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1974 	function = hdr->flags;
1975 
1976 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1977 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1978 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1979 		hdr->rtt, hdr->refcmdsn, conn->cid);
1980 
1981 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1982 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1983 	     hdr->rtt != RESERVED_ITT)) {
1984 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1985 		hdr->rtt = RESERVED_ITT;
1986 	}
1987 
1988 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1989 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1990 		pr_err("Task Management Request TASK_REASSIGN not"
1991 			" issued as immediate command, bad iSCSI Initiator"
1992 				"implementation\n");
1993 		return iscsit_add_reject_cmd(cmd,
1994 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1995 	}
1996 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1997 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
1998 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
1999 
2000 	cmd->data_direction = DMA_NONE;
2001 
2002 	cmd->tmr_req = kzalloc(sizeof(struct iscsi_tmr_req), GFP_KERNEL);
2003 	if (!cmd->tmr_req) {
2004 		pr_err("Unable to allocate memory for"
2005 			" Task Management command!\n");
2006 		return iscsit_add_reject_cmd(cmd,
2007 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
2008 					     buf);
2009 	}
2010 
2011 	/*
2012 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
2013 	 * LIO-Target $FABRIC_MOD
2014 	 */
2015 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2016 		transport_init_se_cmd(&cmd->se_cmd, &iscsi_ops,
2017 				      conn->sess->se_sess, 0, DMA_NONE,
2018 				      TCM_SIMPLE_TAG, cmd->sense_buffer + 2);
2019 
2020 		target_get_sess_cmd(&cmd->se_cmd, true);
2021 		sess_ref = true;
2022 		tcm_function = iscsit_convert_tmf(function);
2023 		if (tcm_function == TMR_UNKNOWN) {
2024 			pr_err("Unknown iSCSI TMR Function:"
2025 			       " 0x%02x\n", function);
2026 			return iscsit_add_reject_cmd(cmd,
2027 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2028 		}
2029 	}
2030 	ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
2031 				 GFP_KERNEL);
2032 	if (ret < 0)
2033 		return iscsit_add_reject_cmd(cmd,
2034 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2035 
2036 	cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2037 
2038 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2039 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2040 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2041 	cmd->init_task_tag	= hdr->itt;
2042 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2043 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2044 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2045 	se_tmr			= cmd->se_cmd.se_tmr_req;
2046 	tmr_req			= cmd->tmr_req;
2047 	/*
2048 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2049 	 */
2050 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2051 		ret = transport_lookup_tmr_lun(&cmd->se_cmd,
2052 					       scsilun_to_int(&hdr->lun));
2053 		if (ret < 0) {
2054 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2055 			goto attach;
2056 		}
2057 	}
2058 
2059 	switch (function) {
2060 	case ISCSI_TM_FUNC_ABORT_TASK:
2061 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2062 		if (se_tmr->response)
2063 			goto attach;
2064 		break;
2065 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2066 	case ISCSI_TM_FUNC_CLEAR_ACA:
2067 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2068 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2069 		break;
2070 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2071 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2072 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2073 			goto attach;
2074 		}
2075 		break;
2076 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2077 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2078 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2079 			goto attach;
2080 		}
2081 		break;
2082 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2083 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2084 		/*
2085 		 * Perform sanity checks on the ExpDataSN only if the
2086 		 * TASK_REASSIGN was successful.
2087 		 */
2088 		if (se_tmr->response)
2089 			break;
2090 
2091 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2092 			return iscsit_add_reject_cmd(cmd,
2093 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2094 		break;
2095 	default:
2096 		pr_err("Unknown TMR function: 0x%02x, protocol"
2097 			" error.\n", function);
2098 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2099 		goto attach;
2100 	}
2101 
2102 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2103 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2104 		se_tmr->call_transport = 1;
2105 attach:
2106 	spin_lock_bh(&conn->cmd_lock);
2107 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2108 	spin_unlock_bh(&conn->cmd_lock);
2109 
2110 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2111 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2112 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP)
2113 			out_of_order_cmdsn = 1;
2114 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2115 			return 0;
2116 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2117 			return -1;
2118 	}
2119 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2120 
2121 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2122 		return 0;
2123 	/*
2124 	 * Found the referenced task, send to transport for processing.
2125 	 */
2126 	if (se_tmr->call_transport)
2127 		return transport_generic_handle_tmr(&cmd->se_cmd);
2128 
2129 	/*
2130 	 * Could not find the referenced LUN, task, or Task Management
2131 	 * command not authorized or supported.  Change state and
2132 	 * let the tx_thread send the response.
2133 	 *
2134 	 * For connection recovery, this is also the default action for
2135 	 * TMR TASK_REASSIGN.
2136 	 */
2137 	if (sess_ref) {
2138 		pr_debug("Handle TMR, using sess_ref=true check\n");
2139 		target_put_sess_cmd(&cmd->se_cmd);
2140 	}
2141 
2142 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2143 	return 0;
2144 }
2145 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2146 
2147 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2148 int
2149 iscsit_setup_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2150 		      struct iscsi_text *hdr)
2151 {
2152 	u32 payload_length = ntoh24(hdr->dlength);
2153 
2154 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2155 		pr_err("Unable to accept text parameter length: %u"
2156 			"greater than MaxXmitDataSegmentLength %u.\n",
2157 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2158 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2159 					 (unsigned char *)hdr);
2160 	}
2161 
2162 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2163 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2164 		pr_err("Multi sequence text commands currently not supported\n");
2165 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2166 					(unsigned char *)hdr);
2167 	}
2168 
2169 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2170 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2171 		hdr->exp_statsn, payload_length);
2172 
2173 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2174 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2175 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2176 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2177 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2178 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2179 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2180 	cmd->data_direction	= DMA_NONE;
2181 	cmd->text_in_ptr	= NULL;
2182 
2183 	return 0;
2184 }
2185 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2186 
2187 int
2188 iscsit_process_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2189 			struct iscsi_text *hdr)
2190 {
2191 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2192 	int cmdsn_ret;
2193 
2194 	if (!text_in) {
2195 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2196 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2197 			pr_err("Unable to locate text_in buffer for sendtargets"
2198 			       " discovery\n");
2199 			goto reject;
2200 		}
2201 		goto empty_sendtargets;
2202 	}
2203 	if (strncmp("SendTargets", text_in, 11) != 0) {
2204 		pr_err("Received Text Data that is not"
2205 			" SendTargets, cannot continue.\n");
2206 		goto reject;
2207 	}
2208 	text_ptr = strchr(text_in, '=');
2209 	if (!text_ptr) {
2210 		pr_err("No \"=\" separator found in Text Data,"
2211 			"  cannot continue.\n");
2212 		goto reject;
2213 	}
2214 	if (!strncmp("=All", text_ptr, 4)) {
2215 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2216 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2217 		   !strncmp("=eui.", text_ptr, 5)) {
2218 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2219 	} else {
2220 		pr_err("Unable to locate valid SendTargets=%s value\n", text_ptr);
2221 		goto reject;
2222 	}
2223 
2224 	spin_lock_bh(&conn->cmd_lock);
2225 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2226 	spin_unlock_bh(&conn->cmd_lock);
2227 
2228 empty_sendtargets:
2229 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2230 
2231 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2232 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2233 				(unsigned char *)hdr, hdr->cmdsn);
2234 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2235 			return -1;
2236 
2237 		return 0;
2238 	}
2239 
2240 	return iscsit_execute_cmd(cmd, 0);
2241 
2242 reject:
2243 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2244 				 (unsigned char *)hdr);
2245 }
2246 EXPORT_SYMBOL(iscsit_process_text_cmd);
2247 
2248 static int
2249 iscsit_handle_text_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2250 		       unsigned char *buf)
2251 {
2252 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2253 	char *text_in = NULL;
2254 	u32 payload_length = ntoh24(hdr->dlength);
2255 	int rx_size, rc;
2256 
2257 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2258 	if (rc < 0)
2259 		return 0;
2260 
2261 	rx_size = payload_length;
2262 	if (payload_length) {
2263 		u32 checksum = 0, data_crc = 0;
2264 		u32 padding = 0, pad_bytes = 0;
2265 		int niov = 0, rx_got;
2266 		struct kvec iov[3];
2267 
2268 		text_in = kzalloc(payload_length, GFP_KERNEL);
2269 		if (!text_in) {
2270 			pr_err("Unable to allocate memory for"
2271 				" incoming text parameters\n");
2272 			goto reject;
2273 		}
2274 		cmd->text_in_ptr = text_in;
2275 
2276 		memset(iov, 0, 3 * sizeof(struct kvec));
2277 		iov[niov].iov_base	= text_in;
2278 		iov[niov++].iov_len	= payload_length;
2279 
2280 		padding = ((-payload_length) & 3);
2281 		if (padding != 0) {
2282 			iov[niov].iov_base = &pad_bytes;
2283 			iov[niov++].iov_len  = padding;
2284 			rx_size += padding;
2285 			pr_debug("Receiving %u additional bytes"
2286 					" for padding.\n", padding);
2287 		}
2288 		if (conn->conn_ops->DataDigest) {
2289 			iov[niov].iov_base	= &checksum;
2290 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2291 			rx_size += ISCSI_CRC_LEN;
2292 		}
2293 
2294 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2295 		if (rx_got != rx_size)
2296 			goto reject;
2297 
2298 		if (conn->conn_ops->DataDigest) {
2299 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2300 					text_in, payload_length,
2301 					padding, (u8 *)&pad_bytes,
2302 					(u8 *)&data_crc);
2303 
2304 			if (checksum != data_crc) {
2305 				pr_err("Text data CRC32C DataDigest"
2306 					" 0x%08x does not match computed"
2307 					" 0x%08x\n", checksum, data_crc);
2308 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2309 					pr_err("Unable to recover from"
2310 					" Text Data digest failure while in"
2311 						" ERL=0.\n");
2312 					goto reject;
2313 				} else {
2314 					/*
2315 					 * Silently drop this PDU and let the
2316 					 * initiator plug the CmdSN gap.
2317 					 */
2318 					pr_debug("Dropping Text"
2319 					" Command CmdSN: 0x%08x due to"
2320 					" DataCRC error.\n", hdr->cmdsn);
2321 					kfree(text_in);
2322 					return 0;
2323 				}
2324 			} else {
2325 				pr_debug("Got CRC32C DataDigest"
2326 					" 0x%08x for %u bytes of text data.\n",
2327 						checksum, payload_length);
2328 			}
2329 		}
2330 		text_in[payload_length - 1] = '\0';
2331 		pr_debug("Successfully read %d bytes of text"
2332 				" data.\n", payload_length);
2333 	}
2334 
2335 	return iscsit_process_text_cmd(conn, cmd, hdr);
2336 
2337 reject:
2338 	kfree(cmd->text_in_ptr);
2339 	cmd->text_in_ptr = NULL;
2340 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2341 }
2342 
2343 int iscsit_logout_closesession(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2344 {
2345 	struct iscsi_conn *conn_p;
2346 	struct iscsi_session *sess = conn->sess;
2347 
2348 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2349 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2350 
2351 	atomic_set(&sess->session_logout, 1);
2352 	atomic_set(&conn->conn_logout_remove, 1);
2353 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2354 
2355 	iscsit_inc_conn_usage_count(conn);
2356 	iscsit_inc_session_usage_count(sess);
2357 
2358 	spin_lock_bh(&sess->conn_lock);
2359 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2360 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2361 			continue;
2362 
2363 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2364 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2365 	}
2366 	spin_unlock_bh(&sess->conn_lock);
2367 
2368 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2369 
2370 	return 0;
2371 }
2372 
2373 int iscsit_logout_closeconnection(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2374 {
2375 	struct iscsi_conn *l_conn;
2376 	struct iscsi_session *sess = conn->sess;
2377 
2378 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2379 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2380 
2381 	/*
2382 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2383 	 * can arrive on a connection with a differing CID.
2384 	 */
2385 	if (conn->cid == cmd->logout_cid) {
2386 		spin_lock_bh(&conn->state_lock);
2387 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2388 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2389 
2390 		atomic_set(&conn->conn_logout_remove, 1);
2391 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2392 		iscsit_inc_conn_usage_count(conn);
2393 
2394 		spin_unlock_bh(&conn->state_lock);
2395 	} else {
2396 		/*
2397 		 * Handle all different cid CLOSECONNECTION requests in
2398 		 * iscsit_logout_post_handler_diffcid() as to give enough
2399 		 * time for any non immediate command's CmdSN to be
2400 		 * acknowledged on the connection in question.
2401 		 *
2402 		 * Here we simply make sure the CID is still around.
2403 		 */
2404 		l_conn = iscsit_get_conn_from_cid(sess,
2405 				cmd->logout_cid);
2406 		if (!l_conn) {
2407 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2408 			iscsit_add_cmd_to_response_queue(cmd, conn,
2409 					cmd->i_state);
2410 			return 0;
2411 		}
2412 
2413 		iscsit_dec_conn_usage_count(l_conn);
2414 	}
2415 
2416 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2417 
2418 	return 0;
2419 }
2420 
2421 int iscsit_logout_removeconnforrecovery(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2422 {
2423 	struct iscsi_session *sess = conn->sess;
2424 
2425 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2426 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2427 
2428 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2429 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2430 			" while ERL!=2.\n");
2431 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2432 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2433 		return 0;
2434 	}
2435 
2436 	if (conn->cid == cmd->logout_cid) {
2437 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2438 			" with CID: %hu on CID: %hu, implementation error.\n",
2439 				cmd->logout_cid, conn->cid);
2440 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2441 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2442 		return 0;
2443 	}
2444 
2445 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2446 
2447 	return 0;
2448 }
2449 
2450 int
2451 iscsit_handle_logout_cmd(struct iscsi_conn *conn, struct iscsi_cmd *cmd,
2452 			unsigned char *buf)
2453 {
2454 	int cmdsn_ret, logout_remove = 0;
2455 	u8 reason_code = 0;
2456 	struct iscsi_logout *hdr;
2457 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2458 
2459 	hdr			= (struct iscsi_logout *) buf;
2460 	reason_code		= (hdr->flags & 0x7f);
2461 
2462 	if (tiqn) {
2463 		spin_lock(&tiqn->logout_stats.lock);
2464 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2465 			tiqn->logout_stats.normal_logouts++;
2466 		else
2467 			tiqn->logout_stats.abnormal_logouts++;
2468 		spin_unlock(&tiqn->logout_stats.lock);
2469 	}
2470 
2471 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2472 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2473 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2474 		hdr->cid, conn->cid);
2475 
2476 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2477 		pr_err("Received logout request on connection that"
2478 			" is not in logged in state, ignoring request.\n");
2479 		iscsit_free_cmd(cmd, false);
2480 		return 0;
2481 	}
2482 
2483 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2484 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2485 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2486 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2487 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2488 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2489 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2490 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2491 	cmd->logout_reason      = reason_code;
2492 	cmd->data_direction     = DMA_NONE;
2493 
2494 	/*
2495 	 * We need to sleep in these cases (by returning 1) until the Logout
2496 	 * Response gets sent in the tx thread.
2497 	 */
2498 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2499 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2500 	    be16_to_cpu(hdr->cid) == conn->cid))
2501 		logout_remove = 1;
2502 
2503 	spin_lock_bh(&conn->cmd_lock);
2504 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2505 	spin_unlock_bh(&conn->cmd_lock);
2506 
2507 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2508 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2509 
2510 	/*
2511 	 * Immediate commands are executed, well, immediately.
2512 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2513 	 */
2514 	if (cmd->immediate_cmd) {
2515 		int ret = iscsit_execute_cmd(cmd, 0);
2516 
2517 		if (ret < 0)
2518 			return ret;
2519 	} else {
2520 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2521 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2522 			logout_remove = 0;
2523 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2524 			return -1;
2525 	}
2526 
2527 	return logout_remove;
2528 }
2529 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2530 
2531 int iscsit_handle_snack(
2532 	struct iscsi_conn *conn,
2533 	unsigned char *buf)
2534 {
2535 	struct iscsi_snack *hdr;
2536 
2537 	hdr			= (struct iscsi_snack *) buf;
2538 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2539 
2540 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2541 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2542 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2543 			hdr->begrun, hdr->runlength, conn->cid);
2544 
2545 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2546 		pr_err("Initiator sent SNACK request while in"
2547 			" ErrorRecoveryLevel=0.\n");
2548 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2549 					 buf);
2550 	}
2551 	/*
2552 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2553 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2554 	 */
2555 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2556 	case 0:
2557 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2558 			hdr->itt,
2559 			be32_to_cpu(hdr->ttt),
2560 			be32_to_cpu(hdr->begrun),
2561 			be32_to_cpu(hdr->runlength));
2562 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2563 		return iscsit_handle_status_snack(conn, hdr->itt,
2564 			be32_to_cpu(hdr->ttt),
2565 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2566 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2567 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2568 			be32_to_cpu(hdr->begrun),
2569 			be32_to_cpu(hdr->runlength));
2570 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2571 		/* FIXME: Support R-Data SNACK */
2572 		pr_err("R-Data SNACK Not Supported.\n");
2573 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2574 					 buf);
2575 	default:
2576 		pr_err("Unknown SNACK type 0x%02x, protocol"
2577 			" error.\n", hdr->flags & 0x0f);
2578 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2579 					 buf);
2580 	}
2581 
2582 	return 0;
2583 }
2584 EXPORT_SYMBOL(iscsit_handle_snack);
2585 
2586 static void iscsit_rx_thread_wait_for_tcp(struct iscsi_conn *conn)
2587 {
2588 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2589 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2590 		wait_for_completion_interruptible_timeout(
2591 					&conn->rx_half_close_comp,
2592 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2593 	}
2594 }
2595 
2596 static int iscsit_handle_immediate_data(
2597 	struct iscsi_cmd *cmd,
2598 	struct iscsi_scsi_req *hdr,
2599 	u32 length)
2600 {
2601 	int iov_ret, rx_got = 0, rx_size = 0;
2602 	u32 checksum, iov_count = 0, padding = 0;
2603 	struct iscsi_conn *conn = cmd->conn;
2604 	struct kvec *iov;
2605 
2606 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data, cmd->write_data_done, length);
2607 	if (iov_ret < 0)
2608 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2609 
2610 	rx_size = length;
2611 	iov_count = iov_ret;
2612 	iov = &cmd->iov_data[0];
2613 
2614 	padding = ((-length) & 3);
2615 	if (padding != 0) {
2616 		iov[iov_count].iov_base	= cmd->pad_bytes;
2617 		iov[iov_count++].iov_len = padding;
2618 		rx_size += padding;
2619 	}
2620 
2621 	if (conn->conn_ops->DataDigest) {
2622 		iov[iov_count].iov_base		= &checksum;
2623 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2624 		rx_size += ISCSI_CRC_LEN;
2625 	}
2626 
2627 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2628 
2629 	iscsit_unmap_iovec(cmd);
2630 
2631 	if (rx_got != rx_size) {
2632 		iscsit_rx_thread_wait_for_tcp(conn);
2633 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2634 	}
2635 
2636 	if (conn->conn_ops->DataDigest) {
2637 		u32 data_crc;
2638 
2639 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2640 						    cmd->write_data_done, length, padding,
2641 						    cmd->pad_bytes);
2642 
2643 		if (checksum != data_crc) {
2644 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2645 				" does not match computed 0x%08x\n", checksum,
2646 				data_crc);
2647 
2648 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2649 				pr_err("Unable to recover from"
2650 					" Immediate Data digest failure while"
2651 					" in ERL=0.\n");
2652 				iscsit_reject_cmd(cmd,
2653 						ISCSI_REASON_DATA_DIGEST_ERROR,
2654 						(unsigned char *)hdr);
2655 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2656 			} else {
2657 				iscsit_reject_cmd(cmd,
2658 						ISCSI_REASON_DATA_DIGEST_ERROR,
2659 						(unsigned char *)hdr);
2660 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2661 			}
2662 		} else {
2663 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2664 				" %u bytes of Immediate Data\n", checksum,
2665 				length);
2666 		}
2667 	}
2668 
2669 	cmd->write_data_done += length;
2670 
2671 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2672 		spin_lock_bh(&cmd->istate_lock);
2673 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2674 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2675 		spin_unlock_bh(&cmd->istate_lock);
2676 	}
2677 
2678 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2679 }
2680 
2681 /*
2682  *	Called with sess->conn_lock held.
2683  */
2684 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2685 	with active network interface */
2686 static void iscsit_build_conn_drop_async_message(struct iscsi_conn *conn)
2687 {
2688 	struct iscsi_cmd *cmd;
2689 	struct iscsi_conn *conn_p;
2690 	bool found = false;
2691 
2692 	/*
2693 	 * Only send a Asynchronous Message on connections whos network
2694 	 * interface is still functional.
2695 	 */
2696 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2697 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2698 			iscsit_inc_conn_usage_count(conn_p);
2699 			found = true;
2700 			break;
2701 		}
2702 	}
2703 
2704 	if (!found)
2705 		return;
2706 
2707 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2708 	if (!cmd) {
2709 		iscsit_dec_conn_usage_count(conn_p);
2710 		return;
2711 	}
2712 
2713 	cmd->logout_cid = conn->cid;
2714 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2715 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2716 
2717 	spin_lock_bh(&conn_p->cmd_lock);
2718 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2719 	spin_unlock_bh(&conn_p->cmd_lock);
2720 
2721 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2722 	iscsit_dec_conn_usage_count(conn_p);
2723 }
2724 
2725 static int iscsit_send_conn_drop_async_message(
2726 	struct iscsi_cmd *cmd,
2727 	struct iscsi_conn *conn)
2728 {
2729 	struct iscsi_async *hdr;
2730 
2731 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2732 
2733 	hdr			= (struct iscsi_async *) cmd->pdu;
2734 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2735 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2736 	cmd->init_task_tag	= RESERVED_ITT;
2737 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2738 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2739 	cmd->stat_sn		= conn->stat_sn++;
2740 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2741 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2742 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2743 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2744 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2745 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2746 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2747 
2748 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2749 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2750 			cmd->logout_cid, conn->cid);
2751 
2752 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2753 }
2754 
2755 static void iscsit_tx_thread_wait_for_tcp(struct iscsi_conn *conn)
2756 {
2757 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2758 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2759 		wait_for_completion_interruptible_timeout(
2760 					&conn->tx_half_close_comp,
2761 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2762 	}
2763 }
2764 
2765 void
2766 iscsit_build_datain_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2767 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2768 			bool set_statsn)
2769 {
2770 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2771 	hdr->flags		= datain->flags;
2772 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2773 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2774 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2775 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2776 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2777 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2778 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2779 		}
2780 	}
2781 	hton24(hdr->dlength, datain->length);
2782 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2783 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2784 				(struct scsi_lun *)&hdr->lun);
2785 	else
2786 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2787 
2788 	hdr->itt		= cmd->init_task_tag;
2789 
2790 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2791 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2792 	else
2793 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2794 	if (set_statsn)
2795 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2796 	else
2797 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2798 
2799 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2800 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2801 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2802 	hdr->offset		= cpu_to_be32(datain->offset);
2803 
2804 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2805 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2806 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2807 		ntohl(hdr->offset), datain->length, conn->cid);
2808 }
2809 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2810 
2811 static int iscsit_send_datain(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2812 {
2813 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2814 	struct iscsi_datain datain;
2815 	struct iscsi_datain_req *dr;
2816 	int eodr = 0, ret;
2817 	bool set_statsn = false;
2818 
2819 	memset(&datain, 0, sizeof(struct iscsi_datain));
2820 	dr = iscsit_get_datain_values(cmd, &datain);
2821 	if (!dr) {
2822 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2823 				cmd->init_task_tag);
2824 		return -1;
2825 	}
2826 	/*
2827 	 * Be paranoid and double check the logic for now.
2828 	 */
2829 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2830 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2831 			" datain.length: %u exceeds cmd->data_length: %u\n",
2832 			cmd->init_task_tag, datain.offset, datain.length,
2833 			cmd->se_cmd.data_length);
2834 		return -1;
2835 	}
2836 
2837 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2838 	/*
2839 	 * Special case for successfully execution w/ both DATAIN
2840 	 * and Sense Data.
2841 	 */
2842 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2843 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2844 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2845 	else {
2846 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2847 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2848 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2849 			cmd->stat_sn = conn->stat_sn++;
2850 			set_statsn = true;
2851 		} else if (dr->dr_complete ==
2852 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2853 			set_statsn = true;
2854 	}
2855 
2856 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2857 
2858 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2859 	if (ret < 0)
2860 		return ret;
2861 
2862 	if (dr->dr_complete) {
2863 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2864 				2 : 1;
2865 		iscsit_free_datain_req(cmd, dr);
2866 	}
2867 
2868 	return eodr;
2869 }
2870 
2871 int
2872 iscsit_build_logout_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2873 			struct iscsi_logout_rsp *hdr)
2874 {
2875 	struct iscsi_conn *logout_conn = NULL;
2876 	struct iscsi_conn_recovery *cr = NULL;
2877 	struct iscsi_session *sess = conn->sess;
2878 	/*
2879 	 * The actual shutting down of Sessions and/or Connections
2880 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2881 	 * is done in scsi_logout_post_handler().
2882 	 */
2883 	switch (cmd->logout_reason) {
2884 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2885 		pr_debug("iSCSI session logout successful, setting"
2886 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2887 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2888 		break;
2889 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2890 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2891 			break;
2892 		/*
2893 		 * For CLOSECONNECTION logout requests carrying
2894 		 * a matching logout CID -> local CID, the reference
2895 		 * for the local CID will have been incremented in
2896 		 * iscsi_logout_closeconnection().
2897 		 *
2898 		 * For CLOSECONNECTION logout requests carrying
2899 		 * a different CID than the connection it arrived
2900 		 * on, the connection responding to cmd->logout_cid
2901 		 * is stopped in iscsit_logout_post_handler_diffcid().
2902 		 */
2903 
2904 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2905 			" successful.\n", cmd->logout_cid, conn->cid);
2906 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2907 		break;
2908 	case ISCSI_LOGOUT_REASON_RECOVERY:
2909 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2910 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2911 			break;
2912 		/*
2913 		 * If the connection is still active from our point of view
2914 		 * force connection recovery to occur.
2915 		 */
2916 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2917 				cmd->logout_cid);
2918 		if (logout_conn) {
2919 			iscsit_connection_reinstatement_rcfr(logout_conn);
2920 			iscsit_dec_conn_usage_count(logout_conn);
2921 		}
2922 
2923 		cr = iscsit_get_inactive_connection_recovery_entry(
2924 				conn->sess, cmd->logout_cid);
2925 		if (!cr) {
2926 			pr_err("Unable to locate CID: %hu for"
2927 			" REMOVECONNFORRECOVERY Logout Request.\n",
2928 				cmd->logout_cid);
2929 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2930 			break;
2931 		}
2932 
2933 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2934 
2935 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2936 			" for recovery for CID: %hu on CID: %hu successful.\n",
2937 				cmd->logout_cid, conn->cid);
2938 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2939 		break;
2940 	default:
2941 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2942 				cmd->logout_reason);
2943 		return -1;
2944 	}
2945 
2946 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2947 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2948 	hdr->response		= cmd->logout_response;
2949 	hdr->itt		= cmd->init_task_tag;
2950 	cmd->stat_sn		= conn->stat_sn++;
2951 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2952 
2953 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2954 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2955 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2956 
2957 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2958 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2959 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2960 		cmd->logout_cid, conn->cid);
2961 
2962 	return 0;
2963 }
2964 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2965 
2966 static int
2967 iscsit_send_logout(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
2968 {
2969 	int rc;
2970 
2971 	rc = iscsit_build_logout_rsp(cmd, conn,
2972 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2973 	if (rc < 0)
2974 		return rc;
2975 
2976 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2977 }
2978 
2979 void
2980 iscsit_build_nopin_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
2981 		       struct iscsi_nopin *hdr, bool nopout_response)
2982 {
2983 	hdr->opcode		= ISCSI_OP_NOOP_IN;
2984 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2985         hton24(hdr->dlength, cmd->buf_ptr_size);
2986 	if (nopout_response)
2987 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2988 	hdr->itt		= cmd->init_task_tag;
2989 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2990 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
2991 				  conn->stat_sn;
2992 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2993 
2994 	if (nopout_response)
2995 		iscsit_increment_maxcmdsn(cmd, conn->sess);
2996 
2997 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2998 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2999 
3000 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
3001 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
3002 		"Solicited" : "Unsolicited", cmd->init_task_tag,
3003 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
3004 }
3005 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
3006 
3007 /*
3008  *	Unsolicited NOPIN, either requesting a response or not.
3009  */
3010 static int iscsit_send_unsolicited_nopin(
3011 	struct iscsi_cmd *cmd,
3012 	struct iscsi_conn *conn,
3013 	int want_response)
3014 {
3015 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3016 	int ret;
3017 
3018 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3019 
3020 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3021 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3022 
3023 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3024 	if (ret < 0)
3025 		return ret;
3026 
3027 	spin_lock_bh(&cmd->istate_lock);
3028 	cmd->i_state = want_response ?
3029 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3030 	spin_unlock_bh(&cmd->istate_lock);
3031 
3032 	return 0;
3033 }
3034 
3035 static int
3036 iscsit_send_nopin(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3037 {
3038 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3039 
3040 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3041 
3042 	/*
3043 	 * NOPOUT Ping Data is attached to struct iscsi_cmd->buf_ptr.
3044 	 * NOPOUT DataSegmentLength is at struct iscsi_cmd->buf_ptr_size.
3045 	 */
3046 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3047 
3048 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3049 						     cmd->buf_ptr,
3050 						     cmd->buf_ptr_size);
3051 }
3052 
3053 static int iscsit_send_r2t(
3054 	struct iscsi_cmd *cmd,
3055 	struct iscsi_conn *conn)
3056 {
3057 	struct iscsi_r2t *r2t;
3058 	struct iscsi_r2t_rsp *hdr;
3059 	int ret;
3060 
3061 	r2t = iscsit_get_r2t_from_list(cmd);
3062 	if (!r2t)
3063 		return -1;
3064 
3065 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3066 	memset(hdr, 0, ISCSI_HDR_LEN);
3067 	hdr->opcode		= ISCSI_OP_R2T;
3068 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3069 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3070 			(struct scsi_lun *)&hdr->lun);
3071 	hdr->itt		= cmd->init_task_tag;
3072 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3073 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3074 	else
3075 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3076 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3077 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3078 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3079 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3080 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3081 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3082 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3083 
3084 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3085 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3086 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3087 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3088 			r2t->offset, r2t->xfer_len, conn->cid);
3089 
3090 	spin_lock_bh(&cmd->r2t_lock);
3091 	r2t->sent_r2t = 1;
3092 	spin_unlock_bh(&cmd->r2t_lock);
3093 
3094 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3095 	if (ret < 0) {
3096 		return ret;
3097 	}
3098 
3099 	spin_lock_bh(&cmd->dataout_timeout_lock);
3100 	iscsit_start_dataout_timer(cmd, conn);
3101 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3102 
3103 	return 0;
3104 }
3105 
3106 /*
3107  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3108  *		connection recovery.
3109  */
3110 int iscsit_build_r2ts_for_cmd(
3111 	struct iscsi_conn *conn,
3112 	struct iscsi_cmd *cmd,
3113 	bool recovery)
3114 {
3115 	int first_r2t = 1;
3116 	u32 offset = 0, xfer_len = 0;
3117 
3118 	spin_lock_bh(&cmd->r2t_lock);
3119 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3120 		spin_unlock_bh(&cmd->r2t_lock);
3121 		return 0;
3122 	}
3123 
3124 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3125 	    !recovery)
3126 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3127 
3128 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3129 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3130 			offset = cmd->r2t_offset;
3131 
3132 			if (first_r2t && recovery) {
3133 				int new_data_end = offset +
3134 					conn->sess->sess_ops->MaxBurstLength -
3135 					cmd->next_burst_len;
3136 
3137 				if (new_data_end > cmd->se_cmd.data_length)
3138 					xfer_len = cmd->se_cmd.data_length - offset;
3139 				else
3140 					xfer_len =
3141 						conn->sess->sess_ops->MaxBurstLength -
3142 						cmd->next_burst_len;
3143 			} else {
3144 				int new_data_end = offset +
3145 					conn->sess->sess_ops->MaxBurstLength;
3146 
3147 				if (new_data_end > cmd->se_cmd.data_length)
3148 					xfer_len = cmd->se_cmd.data_length - offset;
3149 				else
3150 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3151 			}
3152 			cmd->r2t_offset += xfer_len;
3153 
3154 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3155 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3156 		} else {
3157 			struct iscsi_seq *seq;
3158 
3159 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3160 			if (!seq) {
3161 				spin_unlock_bh(&cmd->r2t_lock);
3162 				return -1;
3163 			}
3164 
3165 			offset = seq->offset;
3166 			xfer_len = seq->xfer_len;
3167 
3168 			if (cmd->seq_send_order == cmd->seq_count)
3169 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3170 		}
3171 		cmd->outstanding_r2ts++;
3172 		first_r2t = 0;
3173 
3174 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3175 			spin_unlock_bh(&cmd->r2t_lock);
3176 			return -1;
3177 		}
3178 
3179 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3180 			break;
3181 	}
3182 	spin_unlock_bh(&cmd->r2t_lock);
3183 
3184 	return 0;
3185 }
3186 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3187 
3188 void iscsit_build_rsp_pdu(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3189 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3190 {
3191 	if (inc_stat_sn)
3192 		cmd->stat_sn = conn->stat_sn++;
3193 
3194 	atomic_long_inc(&conn->sess->rsp_pdus);
3195 
3196 	memset(hdr, 0, ISCSI_HDR_LEN);
3197 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3198 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3199 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3200 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3201 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3202 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3203 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3204 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3205 	}
3206 	hdr->response		= cmd->iscsi_response;
3207 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3208 	hdr->itt		= cmd->init_task_tag;
3209 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3210 
3211 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3212 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3213 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3214 
3215 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3216 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3217 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3218 		cmd->se_cmd.scsi_status, conn->cid);
3219 }
3220 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3221 
3222 static int iscsit_send_response(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3223 {
3224 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3225 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3226 	void *data_buf = NULL;
3227 	u32 padding = 0, data_buf_len = 0;
3228 
3229 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3230 
3231 	/*
3232 	 * Attach SENSE DATA payload to iSCSI Response PDU
3233 	 */
3234 	if (cmd->se_cmd.sense_buffer &&
3235 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3236 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3237 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3238 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3239 
3240 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3241 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3242 		data_buf = cmd->sense_buffer;
3243 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3244 
3245 		if (padding) {
3246 			memset(cmd->sense_buffer +
3247 				cmd->se_cmd.scsi_sense_length, 0, padding);
3248 			pr_debug("Adding %u bytes of padding to"
3249 				" SENSE.\n", padding);
3250 		}
3251 
3252 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3253 				" Response PDU\n",
3254 				cmd->se_cmd.scsi_sense_length);
3255 	}
3256 
3257 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3258 						     data_buf_len);
3259 }
3260 
3261 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3262 {
3263 	switch (se_tmr->response) {
3264 	case TMR_FUNCTION_COMPLETE:
3265 		return ISCSI_TMF_RSP_COMPLETE;
3266 	case TMR_TASK_DOES_NOT_EXIST:
3267 		return ISCSI_TMF_RSP_NO_TASK;
3268 	case TMR_LUN_DOES_NOT_EXIST:
3269 		return ISCSI_TMF_RSP_NO_LUN;
3270 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3271 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3272 	case TMR_FUNCTION_REJECTED:
3273 	default:
3274 		return ISCSI_TMF_RSP_REJECTED;
3275 	}
3276 }
3277 
3278 void
3279 iscsit_build_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3280 			  struct iscsi_tm_rsp *hdr)
3281 {
3282 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3283 
3284 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3285 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3286 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3287 	hdr->itt		= cmd->init_task_tag;
3288 	cmd->stat_sn		= conn->stat_sn++;
3289 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3290 
3291 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3292 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3293 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3294 
3295 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3296 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3297 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3298 }
3299 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3300 
3301 static int
3302 iscsit_send_task_mgt_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn)
3303 {
3304 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3305 
3306 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3307 
3308 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3309 }
3310 
3311 static bool iscsit_check_inaddr_any(struct iscsi_np *np)
3312 {
3313 	bool ret = false;
3314 
3315 	if (np->np_sockaddr.ss_family == AF_INET6) {
3316 		const struct sockaddr_in6 sin6 = {
3317 			.sin6_addr = IN6ADDR_ANY_INIT };
3318 		struct sockaddr_in6 *sock_in6 =
3319 			 (struct sockaddr_in6 *)&np->np_sockaddr;
3320 
3321 		if (!memcmp(sock_in6->sin6_addr.s6_addr,
3322 				sin6.sin6_addr.s6_addr, 16))
3323 			ret = true;
3324 	} else {
3325 		struct sockaddr_in * sock_in =
3326 			(struct sockaddr_in *)&np->np_sockaddr;
3327 
3328 		if (sock_in->sin_addr.s_addr == htonl(INADDR_ANY))
3329 			ret = true;
3330 	}
3331 
3332 	return ret;
3333 }
3334 
3335 #define SENDTARGETS_BUF_LIMIT 32768U
3336 
3337 static int
3338 iscsit_build_sendtargets_response(struct iscsi_cmd *cmd,
3339 				  enum iscsit_transport_type network_transport,
3340 				  int skip_bytes, bool *completed)
3341 {
3342 	char *payload = NULL;
3343 	struct iscsi_conn *conn = cmd->conn;
3344 	struct iscsi_portal_group *tpg;
3345 	struct iscsi_tiqn *tiqn;
3346 	struct iscsi_tpg_np *tpg_np;
3347 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3348 	int target_name_printed;
3349 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3350 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3351 	bool active;
3352 
3353 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3354 			 SENDTARGETS_BUF_LIMIT);
3355 
3356 	payload = kzalloc(buffer_len, GFP_KERNEL);
3357 	if (!payload) {
3358 		pr_err("Unable to allocate memory for sendtargets"
3359 				" response.\n");
3360 		return -ENOMEM;
3361 	}
3362 	/*
3363 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3364 	 * explicit case..
3365 	 */
3366 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3367 		text_ptr = strchr(text_in, '=');
3368 		if (!text_ptr) {
3369 			pr_err("Unable to locate '=' string in text_in:"
3370 			       " %s\n", text_in);
3371 			kfree(payload);
3372 			return -EINVAL;
3373 		}
3374 		/*
3375 		 * Skip over '=' character..
3376 		 */
3377 		text_ptr += 1;
3378 	}
3379 
3380 	spin_lock(&tiqn_lock);
3381 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3382 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3383 		     strcmp(tiqn->tiqn, text_ptr)) {
3384 			continue;
3385 		}
3386 
3387 		target_name_printed = 0;
3388 
3389 		spin_lock(&tiqn->tiqn_tpg_lock);
3390 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3391 
3392 			/* If demo_mode_discovery=0 and generate_node_acls=0
3393 			 * (demo mode dislabed) do not return
3394 			 * TargetName+TargetAddress unless a NodeACL exists.
3395 			 */
3396 
3397 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3398 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3399 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3400 				cmd->conn->sess->sess_ops->InitiatorName))) {
3401 				continue;
3402 			}
3403 
3404 			spin_lock(&tpg->tpg_state_lock);
3405 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3406 			spin_unlock(&tpg->tpg_state_lock);
3407 
3408 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3409 				continue;
3410 
3411 			spin_lock(&tpg->tpg_np_lock);
3412 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3413 						tpg_np_list) {
3414 				struct iscsi_np *np = tpg_np->tpg_np;
3415 				bool inaddr_any = iscsit_check_inaddr_any(np);
3416 				struct sockaddr_storage *sockaddr;
3417 
3418 				if (np->np_network_transport != network_transport)
3419 					continue;
3420 
3421 				if (!target_name_printed) {
3422 					len = sprintf(buf, "TargetName=%s",
3423 						      tiqn->tiqn);
3424 					len += 1;
3425 
3426 					if ((len + payload_len) > buffer_len) {
3427 						spin_unlock(&tpg->tpg_np_lock);
3428 						spin_unlock(&tiqn->tiqn_tpg_lock);
3429 						end_of_buf = 1;
3430 						goto eob;
3431 					}
3432 
3433 					if (skip_bytes && len <= skip_bytes) {
3434 						skip_bytes -= len;
3435 					} else {
3436 						memcpy(payload + payload_len, buf, len);
3437 						payload_len += len;
3438 						target_name_printed = 1;
3439 						if (len > skip_bytes)
3440 							skip_bytes = 0;
3441 					}
3442 				}
3443 
3444 				if (inaddr_any)
3445 					sockaddr = &conn->local_sockaddr;
3446 				else
3447 					sockaddr = &np->np_sockaddr;
3448 
3449 				len = sprintf(buf, "TargetAddress="
3450 					      "%pISpc,%hu",
3451 					      sockaddr,
3452 					      tpg->tpgt);
3453 				len += 1;
3454 
3455 				if ((len + payload_len) > buffer_len) {
3456 					spin_unlock(&tpg->tpg_np_lock);
3457 					spin_unlock(&tiqn->tiqn_tpg_lock);
3458 					end_of_buf = 1;
3459 					goto eob;
3460 				}
3461 
3462 				if (skip_bytes && len <= skip_bytes) {
3463 					skip_bytes -= len;
3464 				} else {
3465 					memcpy(payload + payload_len, buf, len);
3466 					payload_len += len;
3467 					if (len > skip_bytes)
3468 						skip_bytes = 0;
3469 				}
3470 			}
3471 			spin_unlock(&tpg->tpg_np_lock);
3472 		}
3473 		spin_unlock(&tiqn->tiqn_tpg_lock);
3474 eob:
3475 		if (end_of_buf) {
3476 			*completed = false;
3477 			break;
3478 		}
3479 
3480 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3481 			break;
3482 	}
3483 	spin_unlock(&tiqn_lock);
3484 
3485 	cmd->buf_ptr = payload;
3486 
3487 	return payload_len;
3488 }
3489 
3490 int
3491 iscsit_build_text_rsp(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3492 		      struct iscsi_text_rsp *hdr,
3493 		      enum iscsit_transport_type network_transport)
3494 {
3495 	int text_length, padding;
3496 	bool completed = true;
3497 
3498 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3499 							cmd->read_data_done,
3500 							&completed);
3501 	if (text_length < 0)
3502 		return text_length;
3503 
3504 	if (completed) {
3505 		hdr->flags |= ISCSI_FLAG_CMD_FINAL;
3506 	} else {
3507 		hdr->flags |= ISCSI_FLAG_TEXT_CONTINUE;
3508 		cmd->read_data_done += text_length;
3509 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3510 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3511 	}
3512 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3513 	padding = ((-text_length) & 3);
3514 	hton24(hdr->dlength, text_length);
3515 	hdr->itt = cmd->init_task_tag;
3516 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3517 	cmd->stat_sn = conn->stat_sn++;
3518 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3519 
3520 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3521 	/*
3522 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3523 	 * correctly increment MaxCmdSN for each response answering a
3524 	 * non immediate text request with a valid CmdSN.
3525 	 */
3526 	cmd->maxcmdsn_inc = 0;
3527 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3528 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3529 
3530 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3531 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3532 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3533 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3534 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3535 
3536 	return text_length + padding;
3537 }
3538 EXPORT_SYMBOL(iscsit_build_text_rsp);
3539 
3540 static int iscsit_send_text_rsp(
3541 	struct iscsi_cmd *cmd,
3542 	struct iscsi_conn *conn)
3543 {
3544 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3545 	int text_length;
3546 
3547 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3548 				conn->conn_transport->transport_type);
3549 	if (text_length < 0)
3550 		return text_length;
3551 
3552 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3553 						     cmd->buf_ptr,
3554 						     text_length);
3555 }
3556 
3557 void
3558 iscsit_build_reject(struct iscsi_cmd *cmd, struct iscsi_conn *conn,
3559 		    struct iscsi_reject *hdr)
3560 {
3561 	hdr->opcode		= ISCSI_OP_REJECT;
3562 	hdr->reason		= cmd->reject_reason;
3563 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3564 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3565 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3566 	cmd->stat_sn		= conn->stat_sn++;
3567 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3568 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3569 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3570 
3571 }
3572 EXPORT_SYMBOL(iscsit_build_reject);
3573 
3574 static int iscsit_send_reject(
3575 	struct iscsi_cmd *cmd,
3576 	struct iscsi_conn *conn)
3577 {
3578 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3579 
3580 	iscsit_build_reject(cmd, conn, hdr);
3581 
3582 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3583 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3584 
3585 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3586 						     cmd->buf_ptr,
3587 						     ISCSI_HDR_LEN);
3588 }
3589 
3590 void iscsit_thread_get_cpumask(struct iscsi_conn *conn)
3591 {
3592 	int ord, cpu;
3593 	/*
3594 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3595 	 * within iscsit_start_kthreads()
3596 	 *
3597 	 * Here we use bitmap_id to determine which CPU that this
3598 	 * iSCSI connection's RX/TX threads will be scheduled to
3599 	 * execute upon.
3600 	 */
3601 	ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3602 	for_each_online_cpu(cpu) {
3603 		if (ord-- == 0) {
3604 			cpumask_set_cpu(cpu, conn->conn_cpumask);
3605 			return;
3606 		}
3607 	}
3608 	/*
3609 	 * This should never be reached..
3610 	 */
3611 	dump_stack();
3612 	cpumask_setall(conn->conn_cpumask);
3613 }
3614 
3615 int
3616 iscsit_immediate_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3617 {
3618 	int ret;
3619 
3620 	switch (state) {
3621 	case ISTATE_SEND_R2T:
3622 		ret = iscsit_send_r2t(cmd, conn);
3623 		if (ret < 0)
3624 			goto err;
3625 		break;
3626 	case ISTATE_REMOVE:
3627 		spin_lock_bh(&conn->cmd_lock);
3628 		list_del_init(&cmd->i_conn_node);
3629 		spin_unlock_bh(&conn->cmd_lock);
3630 
3631 		iscsit_free_cmd(cmd, false);
3632 		break;
3633 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3634 		iscsit_mod_nopin_response_timer(conn);
3635 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3636 		if (ret < 0)
3637 			goto err;
3638 		break;
3639 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3640 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3641 		if (ret < 0)
3642 			goto err;
3643 		break;
3644 	default:
3645 		pr_err("Unknown Opcode: 0x%02x ITT:"
3646 		       " 0x%08x, i_state: %d on CID: %hu\n",
3647 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3648 		       conn->cid);
3649 		goto err;
3650 	}
3651 
3652 	return 0;
3653 
3654 err:
3655 	return -1;
3656 }
3657 EXPORT_SYMBOL(iscsit_immediate_queue);
3658 
3659 static int
3660 iscsit_handle_immediate_queue(struct iscsi_conn *conn)
3661 {
3662 	struct iscsit_transport *t = conn->conn_transport;
3663 	struct iscsi_queue_req *qr;
3664 	struct iscsi_cmd *cmd;
3665 	u8 state;
3666 	int ret;
3667 
3668 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3669 		atomic_set(&conn->check_immediate_queue, 0);
3670 		cmd = qr->cmd;
3671 		state = qr->state;
3672 		kmem_cache_free(lio_qr_cache, qr);
3673 
3674 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3675 		if (ret < 0)
3676 			return ret;
3677 	}
3678 
3679 	return 0;
3680 }
3681 
3682 int
3683 iscsit_response_queue(struct iscsi_conn *conn, struct iscsi_cmd *cmd, int state)
3684 {
3685 	int ret;
3686 
3687 check_rsp_state:
3688 	switch (state) {
3689 	case ISTATE_SEND_DATAIN:
3690 		ret = iscsit_send_datain(cmd, conn);
3691 		if (ret < 0)
3692 			goto err;
3693 		else if (!ret)
3694 			/* more drs */
3695 			goto check_rsp_state;
3696 		else if (ret == 1) {
3697 			/* all done */
3698 			spin_lock_bh(&cmd->istate_lock);
3699 			cmd->i_state = ISTATE_SENT_STATUS;
3700 			spin_unlock_bh(&cmd->istate_lock);
3701 
3702 			if (atomic_read(&conn->check_immediate_queue))
3703 				return 1;
3704 
3705 			return 0;
3706 		} else if (ret == 2) {
3707 			/* Still must send status,
3708 			   SCF_TRANSPORT_TASK_SENSE was set */
3709 			spin_lock_bh(&cmd->istate_lock);
3710 			cmd->i_state = ISTATE_SEND_STATUS;
3711 			spin_unlock_bh(&cmd->istate_lock);
3712 			state = ISTATE_SEND_STATUS;
3713 			goto check_rsp_state;
3714 		}
3715 
3716 		break;
3717 	case ISTATE_SEND_STATUS:
3718 	case ISTATE_SEND_STATUS_RECOVERY:
3719 		ret = iscsit_send_response(cmd, conn);
3720 		break;
3721 	case ISTATE_SEND_LOGOUTRSP:
3722 		ret = iscsit_send_logout(cmd, conn);
3723 		break;
3724 	case ISTATE_SEND_ASYNCMSG:
3725 		ret = iscsit_send_conn_drop_async_message(
3726 			cmd, conn);
3727 		break;
3728 	case ISTATE_SEND_NOPIN:
3729 		ret = iscsit_send_nopin(cmd, conn);
3730 		break;
3731 	case ISTATE_SEND_REJECT:
3732 		ret = iscsit_send_reject(cmd, conn);
3733 		break;
3734 	case ISTATE_SEND_TASKMGTRSP:
3735 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3736 		if (ret != 0)
3737 			break;
3738 		ret = iscsit_tmr_post_handler(cmd, conn);
3739 		if (ret != 0)
3740 			iscsit_fall_back_to_erl0(conn->sess);
3741 		break;
3742 	case ISTATE_SEND_TEXTRSP:
3743 		ret = iscsit_send_text_rsp(cmd, conn);
3744 		break;
3745 	default:
3746 		pr_err("Unknown Opcode: 0x%02x ITT:"
3747 		       " 0x%08x, i_state: %d on CID: %hu\n",
3748 		       cmd->iscsi_opcode, cmd->init_task_tag,
3749 		       state, conn->cid);
3750 		goto err;
3751 	}
3752 	if (ret < 0)
3753 		goto err;
3754 
3755 	switch (state) {
3756 	case ISTATE_SEND_LOGOUTRSP:
3757 		if (!iscsit_logout_post_handler(cmd, conn))
3758 			return -ECONNRESET;
3759 		/* fall through */
3760 	case ISTATE_SEND_STATUS:
3761 	case ISTATE_SEND_ASYNCMSG:
3762 	case ISTATE_SEND_NOPIN:
3763 	case ISTATE_SEND_STATUS_RECOVERY:
3764 	case ISTATE_SEND_TEXTRSP:
3765 	case ISTATE_SEND_TASKMGTRSP:
3766 	case ISTATE_SEND_REJECT:
3767 		spin_lock_bh(&cmd->istate_lock);
3768 		cmd->i_state = ISTATE_SENT_STATUS;
3769 		spin_unlock_bh(&cmd->istate_lock);
3770 		break;
3771 	default:
3772 		pr_err("Unknown Opcode: 0x%02x ITT:"
3773 		       " 0x%08x, i_state: %d on CID: %hu\n",
3774 		       cmd->iscsi_opcode, cmd->init_task_tag,
3775 		       cmd->i_state, conn->cid);
3776 		goto err;
3777 	}
3778 
3779 	if (atomic_read(&conn->check_immediate_queue))
3780 		return 1;
3781 
3782 	return 0;
3783 
3784 err:
3785 	return -1;
3786 }
3787 EXPORT_SYMBOL(iscsit_response_queue);
3788 
3789 static int iscsit_handle_response_queue(struct iscsi_conn *conn)
3790 {
3791 	struct iscsit_transport *t = conn->conn_transport;
3792 	struct iscsi_queue_req *qr;
3793 	struct iscsi_cmd *cmd;
3794 	u8 state;
3795 	int ret;
3796 
3797 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3798 		cmd = qr->cmd;
3799 		state = qr->state;
3800 		kmem_cache_free(lio_qr_cache, qr);
3801 
3802 		ret = t->iscsit_response_queue(conn, cmd, state);
3803 		if (ret == 1 || ret < 0)
3804 			return ret;
3805 	}
3806 
3807 	return 0;
3808 }
3809 
3810 int iscsi_target_tx_thread(void *arg)
3811 {
3812 	int ret = 0;
3813 	struct iscsi_conn *conn = arg;
3814 	/*
3815 	 * Allow ourselves to be interrupted by SIGINT so that a
3816 	 * connection recovery / failure event can be triggered externally.
3817 	 */
3818 	allow_signal(SIGINT);
3819 
3820 	while (!kthread_should_stop()) {
3821 		/*
3822 		 * Ensure that both TX and RX per connection kthreads
3823 		 * are scheduled to run on the same CPU.
3824 		 */
3825 		iscsit_thread_check_cpumask(conn, current, 1);
3826 
3827 		wait_event_interruptible(conn->queues_wq,
3828 					 !iscsit_conn_all_queues_empty(conn));
3829 
3830 		if (signal_pending(current))
3831 			goto transport_err;
3832 
3833 get_immediate:
3834 		ret = iscsit_handle_immediate_queue(conn);
3835 		if (ret < 0)
3836 			goto transport_err;
3837 
3838 		ret = iscsit_handle_response_queue(conn);
3839 		if (ret == 1)
3840 			goto get_immediate;
3841 		else if (ret == -ECONNRESET)
3842 			goto out;
3843 		else if (ret < 0)
3844 			goto transport_err;
3845 	}
3846 
3847 transport_err:
3848 	/*
3849 	 * Avoid the normal connection failure code-path if this connection
3850 	 * is still within LOGIN mode, and iscsi_np process context is
3851 	 * responsible for cleaning up the early connection failure.
3852 	 */
3853 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3854 		iscsit_take_action_for_connection_exit(conn);
3855 out:
3856 	return 0;
3857 }
3858 
3859 static int iscsi_target_rx_opcode(struct iscsi_conn *conn, unsigned char *buf)
3860 {
3861 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3862 	struct iscsi_cmd *cmd;
3863 	int ret = 0;
3864 
3865 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3866 	case ISCSI_OP_SCSI_CMD:
3867 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3868 		if (!cmd)
3869 			goto reject;
3870 
3871 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3872 		break;
3873 	case ISCSI_OP_SCSI_DATA_OUT:
3874 		ret = iscsit_handle_data_out(conn, buf);
3875 		break;
3876 	case ISCSI_OP_NOOP_OUT:
3877 		cmd = NULL;
3878 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3879 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3880 			if (!cmd)
3881 				goto reject;
3882 		}
3883 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3884 		break;
3885 	case ISCSI_OP_SCSI_TMFUNC:
3886 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3887 		if (!cmd)
3888 			goto reject;
3889 
3890 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3891 		break;
3892 	case ISCSI_OP_TEXT:
3893 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3894 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3895 			if (!cmd)
3896 				goto reject;
3897 		} else {
3898 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3899 			if (!cmd)
3900 				goto reject;
3901 		}
3902 
3903 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3904 		break;
3905 	case ISCSI_OP_LOGOUT:
3906 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3907 		if (!cmd)
3908 			goto reject;
3909 
3910 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3911 		if (ret > 0)
3912 			wait_for_completion_timeout(&conn->conn_logout_comp,
3913 					SECONDS_FOR_LOGOUT_COMP * HZ);
3914 		break;
3915 	case ISCSI_OP_SNACK:
3916 		ret = iscsit_handle_snack(conn, buf);
3917 		break;
3918 	default:
3919 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3920 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3921 			pr_err("Cannot recover from unknown"
3922 			" opcode while ERL=0, closing iSCSI connection.\n");
3923 			return -1;
3924 		}
3925 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
3926 		       " closing iSCSI connection.\n");
3927 		ret = -1;
3928 		break;
3929 	}
3930 
3931 	return ret;
3932 reject:
3933 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
3934 }
3935 
3936 static bool iscsi_target_check_conn_state(struct iscsi_conn *conn)
3937 {
3938 	bool ret;
3939 
3940 	spin_lock_bh(&conn->state_lock);
3941 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
3942 	spin_unlock_bh(&conn->state_lock);
3943 
3944 	return ret;
3945 }
3946 
3947 static void iscsit_get_rx_pdu(struct iscsi_conn *conn)
3948 {
3949 	int ret;
3950 	u8 buffer[ISCSI_HDR_LEN], opcode;
3951 	u32 checksum = 0, digest = 0;
3952 	struct kvec iov;
3953 
3954 	while (!kthread_should_stop()) {
3955 		/*
3956 		 * Ensure that both TX and RX per connection kthreads
3957 		 * are scheduled to run on the same CPU.
3958 		 */
3959 		iscsit_thread_check_cpumask(conn, current, 0);
3960 
3961 		memset(buffer, 0, ISCSI_HDR_LEN);
3962 		memset(&iov, 0, sizeof(struct kvec));
3963 
3964 		iov.iov_base	= buffer;
3965 		iov.iov_len	= ISCSI_HDR_LEN;
3966 
3967 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
3968 		if (ret != ISCSI_HDR_LEN) {
3969 			iscsit_rx_thread_wait_for_tcp(conn);
3970 			return;
3971 		}
3972 
3973 		if (conn->conn_ops->HeaderDigest) {
3974 			iov.iov_base	= &digest;
3975 			iov.iov_len	= ISCSI_CRC_LEN;
3976 
3977 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
3978 			if (ret != ISCSI_CRC_LEN) {
3979 				iscsit_rx_thread_wait_for_tcp(conn);
3980 				return;
3981 			}
3982 
3983 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
3984 					buffer, ISCSI_HDR_LEN,
3985 					0, NULL, (u8 *)&checksum);
3986 
3987 			if (digest != checksum) {
3988 				pr_err("HeaderDigest CRC32C failed,"
3989 					" received 0x%08x, computed 0x%08x\n",
3990 					digest, checksum);
3991 				/*
3992 				 * Set the PDU to 0xff so it will intentionally
3993 				 * hit default in the switch below.
3994 				 */
3995 				memset(buffer, 0xff, ISCSI_HDR_LEN);
3996 				atomic_long_inc(&conn->sess->conn_digest_errors);
3997 			} else {
3998 				pr_debug("Got HeaderDigest CRC32C"
3999 						" 0x%08x\n", checksum);
4000 			}
4001 		}
4002 
4003 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4004 			return;
4005 
4006 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4007 
4008 		if (conn->sess->sess_ops->SessionType &&
4009 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4010 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4011 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4012 			" while in Discovery Session, rejecting.\n", opcode);
4013 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4014 					  buffer);
4015 			return;
4016 		}
4017 
4018 		ret = iscsi_target_rx_opcode(conn, buffer);
4019 		if (ret < 0)
4020 			return;
4021 	}
4022 }
4023 
4024 int iscsi_target_rx_thread(void *arg)
4025 {
4026 	int rc;
4027 	struct iscsi_conn *conn = arg;
4028 
4029 	/*
4030 	 * Allow ourselves to be interrupted by SIGINT so that a
4031 	 * connection recovery / failure event can be triggered externally.
4032 	 */
4033 	allow_signal(SIGINT);
4034 	/*
4035 	 * Wait for iscsi_post_login_handler() to complete before allowing
4036 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4037 	 */
4038 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4039 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4040 		return 0;
4041 
4042 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4043 		return 0;
4044 
4045 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4046 
4047 	if (!signal_pending(current))
4048 		atomic_set(&conn->transport_failed, 1);
4049 	iscsit_take_action_for_connection_exit(conn);
4050 	return 0;
4051 }
4052 
4053 static void iscsit_release_commands_from_conn(struct iscsi_conn *conn)
4054 {
4055 	LIST_HEAD(tmp_list);
4056 	struct iscsi_cmd *cmd = NULL, *cmd_tmp = NULL;
4057 	struct iscsi_session *sess = conn->sess;
4058 	/*
4059 	 * We expect this function to only ever be called from either RX or TX
4060 	 * thread context via iscsit_close_connection() once the other context
4061 	 * has been reset -> returned sleeping pre-handler state.
4062 	 */
4063 	spin_lock_bh(&conn->cmd_lock);
4064 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4065 
4066 	list_for_each_entry(cmd, &tmp_list, i_conn_node) {
4067 		struct se_cmd *se_cmd = &cmd->se_cmd;
4068 
4069 		if (se_cmd->se_tfo != NULL) {
4070 			spin_lock(&se_cmd->t_state_lock);
4071 			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4072 			spin_unlock(&se_cmd->t_state_lock);
4073 		}
4074 	}
4075 	spin_unlock_bh(&conn->cmd_lock);
4076 
4077 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4078 		list_del_init(&cmd->i_conn_node);
4079 
4080 		iscsit_increment_maxcmdsn(cmd, sess);
4081 		iscsit_free_cmd(cmd, true);
4082 
4083 	}
4084 }
4085 
4086 static void iscsit_stop_timers_for_cmds(
4087 	struct iscsi_conn *conn)
4088 {
4089 	struct iscsi_cmd *cmd;
4090 
4091 	spin_lock_bh(&conn->cmd_lock);
4092 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4093 		if (cmd->data_direction == DMA_TO_DEVICE)
4094 			iscsit_stop_dataout_timer(cmd);
4095 	}
4096 	spin_unlock_bh(&conn->cmd_lock);
4097 }
4098 
4099 int iscsit_close_connection(
4100 	struct iscsi_conn *conn)
4101 {
4102 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4103 	struct iscsi_session	*sess = conn->sess;
4104 
4105 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4106 		" %u\n", conn->cid, sess->sid);
4107 	/*
4108 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4109 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4110 	 * sleeping and the logout response never got sent because the
4111 	 * connection failed.
4112 	 *
4113 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4114 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4115 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4116 	 * and to avoid iscsi_conn pointer dereference in iser-target code.
4117 	 */
4118 	if (!conn->conn_transport->rdma_shutdown)
4119 		complete(&conn->conn_logout_comp);
4120 
4121 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4122 		if (conn->tx_thread &&
4123 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4124 			send_sig(SIGINT, conn->tx_thread, 1);
4125 			kthread_stop(conn->tx_thread);
4126 		}
4127 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4128 		if (conn->rx_thread &&
4129 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4130 			send_sig(SIGINT, conn->rx_thread, 1);
4131 			kthread_stop(conn->rx_thread);
4132 		}
4133 	}
4134 
4135 	spin_lock(&iscsit_global->ts_bitmap_lock);
4136 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4137 			      get_order(1));
4138 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4139 
4140 	iscsit_stop_timers_for_cmds(conn);
4141 	iscsit_stop_nopin_response_timer(conn);
4142 	iscsit_stop_nopin_timer(conn);
4143 
4144 	if (conn->conn_transport->iscsit_wait_conn)
4145 		conn->conn_transport->iscsit_wait_conn(conn);
4146 
4147 	/*
4148 	 * During Connection recovery drop unacknowledged out of order
4149 	 * commands for this connection, and prepare the other commands
4150 	 * for reallegiance.
4151 	 *
4152 	 * During normal operation clear the out of order commands (but
4153 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4154 	 * struct iscsi_cmds.
4155 	 */
4156 	if (atomic_read(&conn->connection_recovery)) {
4157 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4158 		iscsit_prepare_cmds_for_reallegiance(conn);
4159 	} else {
4160 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4161 		iscsit_release_commands_from_conn(conn);
4162 	}
4163 	iscsit_free_queue_reqs_for_conn(conn);
4164 
4165 	/*
4166 	 * Handle decrementing session or connection usage count if
4167 	 * a logout response was not able to be sent because the
4168 	 * connection failed.  Fall back to Session Recovery here.
4169 	 */
4170 	if (atomic_read(&conn->conn_logout_remove)) {
4171 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4172 			iscsit_dec_conn_usage_count(conn);
4173 			iscsit_dec_session_usage_count(sess);
4174 		}
4175 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4176 			iscsit_dec_conn_usage_count(conn);
4177 
4178 		atomic_set(&conn->conn_logout_remove, 0);
4179 		atomic_set(&sess->session_reinstatement, 0);
4180 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4181 	}
4182 
4183 	spin_lock_bh(&sess->conn_lock);
4184 	list_del(&conn->conn_list);
4185 
4186 	/*
4187 	 * Attempt to let the Initiator know this connection failed by
4188 	 * sending an Connection Dropped Async Message on another
4189 	 * active connection.
4190 	 */
4191 	if (atomic_read(&conn->connection_recovery))
4192 		iscsit_build_conn_drop_async_message(conn);
4193 
4194 	spin_unlock_bh(&sess->conn_lock);
4195 
4196 	/*
4197 	 * If connection reinstatement is being performed on this connection,
4198 	 * up the connection reinstatement semaphore that is being blocked on
4199 	 * in iscsit_cause_connection_reinstatement().
4200 	 */
4201 	spin_lock_bh(&conn->state_lock);
4202 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4203 		spin_unlock_bh(&conn->state_lock);
4204 		complete(&conn->conn_wait_comp);
4205 		wait_for_completion(&conn->conn_post_wait_comp);
4206 		spin_lock_bh(&conn->state_lock);
4207 	}
4208 
4209 	/*
4210 	 * If connection reinstatement is being performed on this connection
4211 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4212 	 * connection wait rcfr semaphore that is being blocked on
4213 	 * an iscsit_connection_reinstatement_rcfr().
4214 	 */
4215 	if (atomic_read(&conn->connection_wait_rcfr)) {
4216 		spin_unlock_bh(&conn->state_lock);
4217 		complete(&conn->conn_wait_rcfr_comp);
4218 		wait_for_completion(&conn->conn_post_wait_comp);
4219 		spin_lock_bh(&conn->state_lock);
4220 	}
4221 	atomic_set(&conn->connection_reinstatement, 1);
4222 	spin_unlock_bh(&conn->state_lock);
4223 
4224 	/*
4225 	 * If any other processes are accessing this connection pointer we
4226 	 * must wait until they have completed.
4227 	 */
4228 	iscsit_check_conn_usage_count(conn);
4229 
4230 	ahash_request_free(conn->conn_tx_hash);
4231 	if (conn->conn_rx_hash) {
4232 		struct crypto_ahash *tfm;
4233 
4234 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4235 		ahash_request_free(conn->conn_rx_hash);
4236 		crypto_free_ahash(tfm);
4237 	}
4238 
4239 	free_cpumask_var(conn->conn_cpumask);
4240 
4241 	kfree(conn->conn_ops);
4242 	conn->conn_ops = NULL;
4243 
4244 	if (conn->sock)
4245 		sock_release(conn->sock);
4246 
4247 	if (conn->conn_transport->iscsit_free_conn)
4248 		conn->conn_transport->iscsit_free_conn(conn);
4249 
4250 	iscsit_put_transport(conn->conn_transport);
4251 
4252 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4253 	conn->conn_state = TARG_CONN_STATE_FREE;
4254 	kfree(conn);
4255 
4256 	spin_lock_bh(&sess->conn_lock);
4257 	atomic_dec(&sess->nconn);
4258 	pr_debug("Decremented iSCSI connection count to %hu from node:"
4259 		" %s\n", atomic_read(&sess->nconn),
4260 		sess->sess_ops->InitiatorName);
4261 	/*
4262 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4263 	 * Session that they all fail.
4264 	 */
4265 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4266 	     !atomic_read(&sess->session_logout))
4267 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4268 
4269 	/*
4270 	 * If this was not the last connection in the session, and we are
4271 	 * performing session reinstatement or falling back to ERL=0, call
4272 	 * iscsit_stop_session() without sleeping to shutdown the other
4273 	 * active connections.
4274 	 */
4275 	if (atomic_read(&sess->nconn)) {
4276 		if (!atomic_read(&sess->session_reinstatement) &&
4277 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4278 			spin_unlock_bh(&sess->conn_lock);
4279 			return 0;
4280 		}
4281 		if (!atomic_read(&sess->session_stop_active)) {
4282 			atomic_set(&sess->session_stop_active, 1);
4283 			spin_unlock_bh(&sess->conn_lock);
4284 			iscsit_stop_session(sess, 0, 0);
4285 			return 0;
4286 		}
4287 		spin_unlock_bh(&sess->conn_lock);
4288 		return 0;
4289 	}
4290 
4291 	/*
4292 	 * If this was the last connection in the session and one of the
4293 	 * following is occurring:
4294 	 *
4295 	 * Session Reinstatement is not being performed, and are falling back
4296 	 * to ERL=0 call iscsit_close_session().
4297 	 *
4298 	 * Session Logout was requested.  iscsit_close_session() will be called
4299 	 * elsewhere.
4300 	 *
4301 	 * Session Continuation is not being performed, start the Time2Retain
4302 	 * handler and check if sleep_on_sess_wait_sem is active.
4303 	 */
4304 	if (!atomic_read(&sess->session_reinstatement) &&
4305 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4306 		spin_unlock_bh(&sess->conn_lock);
4307 		iscsit_close_session(sess);
4308 
4309 		return 0;
4310 	} else if (atomic_read(&sess->session_logout)) {
4311 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4312 		sess->session_state = TARG_SESS_STATE_FREE;
4313 		spin_unlock_bh(&sess->conn_lock);
4314 
4315 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4316 			complete(&sess->session_wait_comp);
4317 
4318 		return 0;
4319 	} else {
4320 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4321 		sess->session_state = TARG_SESS_STATE_FAILED;
4322 
4323 		if (!atomic_read(&sess->session_continuation)) {
4324 			spin_unlock_bh(&sess->conn_lock);
4325 			iscsit_start_time2retain_handler(sess);
4326 		} else
4327 			spin_unlock_bh(&sess->conn_lock);
4328 
4329 		if (atomic_read(&sess->sleep_on_sess_wait_comp))
4330 			complete(&sess->session_wait_comp);
4331 
4332 		return 0;
4333 	}
4334 }
4335 
4336 /*
4337  * If the iSCSI Session for the iSCSI Initiator Node exists,
4338  * forcefully shutdown the iSCSI NEXUS.
4339  */
4340 int iscsit_close_session(struct iscsi_session *sess)
4341 {
4342 	struct iscsi_portal_group *tpg = sess->tpg;
4343 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4344 
4345 	if (atomic_read(&sess->nconn)) {
4346 		pr_err("%d connection(s) still exist for iSCSI session"
4347 			" to %s\n", atomic_read(&sess->nconn),
4348 			sess->sess_ops->InitiatorName);
4349 		BUG();
4350 	}
4351 
4352 	spin_lock_bh(&se_tpg->session_lock);
4353 	atomic_set(&sess->session_logout, 1);
4354 	atomic_set(&sess->session_reinstatement, 1);
4355 	iscsit_stop_time2retain_timer(sess);
4356 	spin_unlock_bh(&se_tpg->session_lock);
4357 
4358 	/*
4359 	 * transport_deregister_session_configfs() will clear the
4360 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4361 	 * can be setting it again with __transport_register_session() in
4362 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4363 	 * completes in iscsi_np context.
4364 	 */
4365 	transport_deregister_session_configfs(sess->se_sess);
4366 
4367 	/*
4368 	 * If any other processes are accessing this session pointer we must
4369 	 * wait until they have completed.  If we are in an interrupt (the
4370 	 * time2retain handler) and contain and active session usage count we
4371 	 * restart the timer and exit.
4372 	 */
4373 	if (!in_interrupt()) {
4374 		if (iscsit_check_session_usage_count(sess) == 1)
4375 			iscsit_stop_session(sess, 1, 1);
4376 	} else {
4377 		if (iscsit_check_session_usage_count(sess) == 2) {
4378 			atomic_set(&sess->session_logout, 0);
4379 			iscsit_start_time2retain_handler(sess);
4380 			return 0;
4381 		}
4382 	}
4383 
4384 	transport_deregister_session(sess->se_sess);
4385 
4386 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4387 		iscsit_free_connection_recovery_entires(sess);
4388 
4389 	iscsit_free_all_ooo_cmdsns(sess);
4390 
4391 	spin_lock_bh(&se_tpg->session_lock);
4392 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4393 	sess->session_state = TARG_SESS_STATE_FREE;
4394 	pr_debug("Released iSCSI session from node: %s\n",
4395 			sess->sess_ops->InitiatorName);
4396 	tpg->nsessions--;
4397 	if (tpg->tpg_tiqn)
4398 		tpg->tpg_tiqn->tiqn_nsessions--;
4399 
4400 	pr_debug("Decremented number of active iSCSI Sessions on"
4401 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4402 
4403 	spin_lock(&sess_idr_lock);
4404 	idr_remove(&sess_idr, sess->session_index);
4405 	spin_unlock(&sess_idr_lock);
4406 
4407 	kfree(sess->sess_ops);
4408 	sess->sess_ops = NULL;
4409 	spin_unlock_bh(&se_tpg->session_lock);
4410 
4411 	kfree(sess);
4412 	return 0;
4413 }
4414 
4415 static void iscsit_logout_post_handler_closesession(
4416 	struct iscsi_conn *conn)
4417 {
4418 	struct iscsi_session *sess = conn->sess;
4419 	int sleep = 1;
4420 	/*
4421 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4422 	 * context during session logout, so clear tx_thread_active and
4423 	 * sleep if iscsit_close_connection() has not already occured.
4424 	 *
4425 	 * Since iser-target invokes this logic from it's own workqueue,
4426 	 * always sleep waiting for RX/TX thread shutdown to complete
4427 	 * within iscsit_close_connection().
4428 	 */
4429 	if (!conn->conn_transport->rdma_shutdown)
4430 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4431 
4432 	atomic_set(&conn->conn_logout_remove, 0);
4433 	complete(&conn->conn_logout_comp);
4434 
4435 	iscsit_dec_conn_usage_count(conn);
4436 	iscsit_stop_session(sess, sleep, sleep);
4437 	iscsit_dec_session_usage_count(sess);
4438 	iscsit_close_session(sess);
4439 }
4440 
4441 static void iscsit_logout_post_handler_samecid(
4442 	struct iscsi_conn *conn)
4443 {
4444 	int sleep = 1;
4445 
4446 	if (!conn->conn_transport->rdma_shutdown)
4447 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4448 
4449 	atomic_set(&conn->conn_logout_remove, 0);
4450 	complete(&conn->conn_logout_comp);
4451 
4452 	iscsit_cause_connection_reinstatement(conn, sleep);
4453 	iscsit_dec_conn_usage_count(conn);
4454 }
4455 
4456 static void iscsit_logout_post_handler_diffcid(
4457 	struct iscsi_conn *conn,
4458 	u16 cid)
4459 {
4460 	struct iscsi_conn *l_conn;
4461 	struct iscsi_session *sess = conn->sess;
4462 	bool conn_found = false;
4463 
4464 	if (!sess)
4465 		return;
4466 
4467 	spin_lock_bh(&sess->conn_lock);
4468 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4469 		if (l_conn->cid == cid) {
4470 			iscsit_inc_conn_usage_count(l_conn);
4471 			conn_found = true;
4472 			break;
4473 		}
4474 	}
4475 	spin_unlock_bh(&sess->conn_lock);
4476 
4477 	if (!conn_found)
4478 		return;
4479 
4480 	if (l_conn->sock)
4481 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4482 
4483 	spin_lock_bh(&l_conn->state_lock);
4484 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4485 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4486 	spin_unlock_bh(&l_conn->state_lock);
4487 
4488 	iscsit_cause_connection_reinstatement(l_conn, 1);
4489 	iscsit_dec_conn_usage_count(l_conn);
4490 }
4491 
4492 /*
4493  *	Return of 0 causes the TX thread to restart.
4494  */
4495 int iscsit_logout_post_handler(
4496 	struct iscsi_cmd *cmd,
4497 	struct iscsi_conn *conn)
4498 {
4499 	int ret = 0;
4500 
4501 	switch (cmd->logout_reason) {
4502 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4503 		switch (cmd->logout_response) {
4504 		case ISCSI_LOGOUT_SUCCESS:
4505 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4506 		default:
4507 			iscsit_logout_post_handler_closesession(conn);
4508 			break;
4509 		}
4510 		ret = 0;
4511 		break;
4512 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4513 		if (conn->cid == cmd->logout_cid) {
4514 			switch (cmd->logout_response) {
4515 			case ISCSI_LOGOUT_SUCCESS:
4516 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4517 			default:
4518 				iscsit_logout_post_handler_samecid(conn);
4519 				break;
4520 			}
4521 			ret = 0;
4522 		} else {
4523 			switch (cmd->logout_response) {
4524 			case ISCSI_LOGOUT_SUCCESS:
4525 				iscsit_logout_post_handler_diffcid(conn,
4526 					cmd->logout_cid);
4527 				break;
4528 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4529 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4530 			default:
4531 				break;
4532 			}
4533 			ret = 1;
4534 		}
4535 		break;
4536 	case ISCSI_LOGOUT_REASON_RECOVERY:
4537 		switch (cmd->logout_response) {
4538 		case ISCSI_LOGOUT_SUCCESS:
4539 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4540 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4541 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4542 		default:
4543 			break;
4544 		}
4545 		ret = 1;
4546 		break;
4547 	default:
4548 		break;
4549 
4550 	}
4551 	return ret;
4552 }
4553 EXPORT_SYMBOL(iscsit_logout_post_handler);
4554 
4555 void iscsit_fail_session(struct iscsi_session *sess)
4556 {
4557 	struct iscsi_conn *conn;
4558 
4559 	spin_lock_bh(&sess->conn_lock);
4560 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4561 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4562 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4563 	}
4564 	spin_unlock_bh(&sess->conn_lock);
4565 
4566 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4567 	sess->session_state = TARG_SESS_STATE_FAILED;
4568 }
4569 
4570 int iscsit_free_session(struct iscsi_session *sess)
4571 {
4572 	u16 conn_count = atomic_read(&sess->nconn);
4573 	struct iscsi_conn *conn, *conn_tmp = NULL;
4574 	int is_last;
4575 
4576 	spin_lock_bh(&sess->conn_lock);
4577 	atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4578 
4579 	list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4580 			conn_list) {
4581 		if (conn_count == 0)
4582 			break;
4583 
4584 		if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4585 			is_last = 1;
4586 		} else {
4587 			iscsit_inc_conn_usage_count(conn_tmp);
4588 			is_last = 0;
4589 		}
4590 		iscsit_inc_conn_usage_count(conn);
4591 
4592 		spin_unlock_bh(&sess->conn_lock);
4593 		iscsit_cause_connection_reinstatement(conn, 1);
4594 		spin_lock_bh(&sess->conn_lock);
4595 
4596 		iscsit_dec_conn_usage_count(conn);
4597 		if (is_last == 0)
4598 			iscsit_dec_conn_usage_count(conn_tmp);
4599 
4600 		conn_count--;
4601 	}
4602 
4603 	if (atomic_read(&sess->nconn)) {
4604 		spin_unlock_bh(&sess->conn_lock);
4605 		wait_for_completion(&sess->session_wait_comp);
4606 	} else
4607 		spin_unlock_bh(&sess->conn_lock);
4608 
4609 	iscsit_close_session(sess);
4610 	return 0;
4611 }
4612 
4613 void iscsit_stop_session(
4614 	struct iscsi_session *sess,
4615 	int session_sleep,
4616 	int connection_sleep)
4617 {
4618 	u16 conn_count = atomic_read(&sess->nconn);
4619 	struct iscsi_conn *conn, *conn_tmp = NULL;
4620 	int is_last;
4621 
4622 	spin_lock_bh(&sess->conn_lock);
4623 	if (session_sleep)
4624 		atomic_set(&sess->sleep_on_sess_wait_comp, 1);
4625 
4626 	if (connection_sleep) {
4627 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4628 				conn_list) {
4629 			if (conn_count == 0)
4630 				break;
4631 
4632 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4633 				is_last = 1;
4634 			} else {
4635 				iscsit_inc_conn_usage_count(conn_tmp);
4636 				is_last = 0;
4637 			}
4638 			iscsit_inc_conn_usage_count(conn);
4639 
4640 			spin_unlock_bh(&sess->conn_lock);
4641 			iscsit_cause_connection_reinstatement(conn, 1);
4642 			spin_lock_bh(&sess->conn_lock);
4643 
4644 			iscsit_dec_conn_usage_count(conn);
4645 			if (is_last == 0)
4646 				iscsit_dec_conn_usage_count(conn_tmp);
4647 			conn_count--;
4648 		}
4649 	} else {
4650 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4651 			iscsit_cause_connection_reinstatement(conn, 0);
4652 	}
4653 
4654 	if (session_sleep && atomic_read(&sess->nconn)) {
4655 		spin_unlock_bh(&sess->conn_lock);
4656 		wait_for_completion(&sess->session_wait_comp);
4657 	} else
4658 		spin_unlock_bh(&sess->conn_lock);
4659 }
4660 
4661 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4662 {
4663 	struct iscsi_session *sess;
4664 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4665 	struct se_session *se_sess, *se_sess_tmp;
4666 	LIST_HEAD(free_list);
4667 	int session_count = 0;
4668 
4669 	spin_lock_bh(&se_tpg->session_lock);
4670 	if (tpg->nsessions && !force) {
4671 		spin_unlock_bh(&se_tpg->session_lock);
4672 		return -1;
4673 	}
4674 
4675 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4676 			sess_list) {
4677 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4678 
4679 		spin_lock(&sess->conn_lock);
4680 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4681 		    atomic_read(&sess->session_logout) ||
4682 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4683 			spin_unlock(&sess->conn_lock);
4684 			continue;
4685 		}
4686 		atomic_set(&sess->session_reinstatement, 1);
4687 		spin_unlock(&sess->conn_lock);
4688 
4689 		list_move_tail(&se_sess->sess_list, &free_list);
4690 	}
4691 	spin_unlock_bh(&se_tpg->session_lock);
4692 
4693 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4694 		sess = (struct iscsi_session *)se_sess->fabric_sess_ptr;
4695 
4696 		iscsit_free_session(sess);
4697 		session_count++;
4698 	}
4699 
4700 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4701 			" Group: %hu\n", session_count, tpg->tpgt);
4702 	return 0;
4703 }
4704 
4705 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4706 MODULE_VERSION("4.1.x");
4707 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4708 MODULE_LICENSE("GPL");
4709 
4710 module_init(iscsi_target_init_module);
4711 module_exit(iscsi_target_cleanup_module);
4712