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