1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * This file contains main functions related to the iSCSI Target Core Driver.
4  *
5  * (c) Copyright 2007-2013 Datera, Inc.
6  *
7  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
8  *
9  ******************************************************************************/
10 
11 #include <crypto/hash.h>
12 #include <linux/string.h>
13 #include <linux/kthread.h>
14 #include <linux/completion.h>
15 #include <linux/module.h>
16 #include <linux/vmalloc.h>
17 #include <linux/idr.h>
18 #include <linux/delay.h>
19 #include <linux/sched/signal.h>
20 #include <asm/unaligned.h>
21 #include <linux/inet.h>
22 #include <net/ipv6.h>
23 #include <scsi/scsi_proto.h>
24 #include <scsi/iscsi_proto.h>
25 #include <scsi/scsi_tcq.h>
26 #include <target/target_core_base.h>
27 #include <target/target_core_fabric.h>
28 
29 #include <target/iscsi/iscsi_target_core.h>
30 #include "iscsi_target_parameters.h"
31 #include "iscsi_target_seq_pdu_list.h"
32 #include "iscsi_target_datain_values.h"
33 #include "iscsi_target_erl0.h"
34 #include "iscsi_target_erl1.h"
35 #include "iscsi_target_erl2.h"
36 #include "iscsi_target_login.h"
37 #include "iscsi_target_tmr.h"
38 #include "iscsi_target_tpg.h"
39 #include "iscsi_target_util.h"
40 #include "iscsi_target.h"
41 #include "iscsi_target_device.h"
42 #include <target/iscsi/iscsi_target_stat.h>
43 
44 #include <target/iscsi/iscsi_transport.h>
45 
46 static LIST_HEAD(g_tiqn_list);
47 static LIST_HEAD(g_np_list);
48 static DEFINE_SPINLOCK(tiqn_lock);
49 static DEFINE_MUTEX(np_lock);
50 
51 static struct idr tiqn_idr;
52 DEFINE_IDA(sess_ida);
53 struct mutex auth_id_lock;
54 
55 struct iscsit_global *iscsit_global;
56 
57 struct kmem_cache *lio_qr_cache;
58 struct kmem_cache *lio_dr_cache;
59 struct kmem_cache *lio_ooo_cache;
60 struct kmem_cache *lio_r2t_cache;
61 
62 static int iscsit_handle_immediate_data(struct iscsit_cmd *,
63 			struct iscsi_scsi_req *, u32);
64 
65 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
66 {
67 	struct iscsi_tiqn *tiqn = NULL;
68 
69 	spin_lock(&tiqn_lock);
70 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
71 		if (!strcmp(tiqn->tiqn, buf)) {
72 
73 			spin_lock(&tiqn->tiqn_state_lock);
74 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
75 				tiqn->tiqn_access_count++;
76 				spin_unlock(&tiqn->tiqn_state_lock);
77 				spin_unlock(&tiqn_lock);
78 				return tiqn;
79 			}
80 			spin_unlock(&tiqn->tiqn_state_lock);
81 		}
82 	}
83 	spin_unlock(&tiqn_lock);
84 
85 	return NULL;
86 }
87 
88 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
89 {
90 	spin_lock(&tiqn->tiqn_state_lock);
91 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
92 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
93 		spin_unlock(&tiqn->tiqn_state_lock);
94 		return 0;
95 	}
96 	spin_unlock(&tiqn->tiqn_state_lock);
97 
98 	return -1;
99 }
100 
101 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
102 {
103 	spin_lock(&tiqn->tiqn_state_lock);
104 	tiqn->tiqn_access_count--;
105 	spin_unlock(&tiqn->tiqn_state_lock);
106 }
107 
108 /*
109  * Note that IQN formatting is expected to be done in userspace, and
110  * no explict IQN format checks are done here.
111  */
112 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
113 {
114 	struct iscsi_tiqn *tiqn = NULL;
115 	int ret;
116 
117 	if (strlen(buf) >= ISCSI_IQN_LEN) {
118 		pr_err("Target IQN exceeds %d bytes\n",
119 				ISCSI_IQN_LEN);
120 		return ERR_PTR(-EINVAL);
121 	}
122 
123 	tiqn = kzalloc(sizeof(*tiqn), GFP_KERNEL);
124 	if (!tiqn)
125 		return ERR_PTR(-ENOMEM);
126 
127 	sprintf(tiqn->tiqn, "%s", buf);
128 	INIT_LIST_HEAD(&tiqn->tiqn_list);
129 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
130 	spin_lock_init(&tiqn->tiqn_state_lock);
131 	spin_lock_init(&tiqn->tiqn_tpg_lock);
132 	spin_lock_init(&tiqn->sess_err_stats.lock);
133 	spin_lock_init(&tiqn->login_stats.lock);
134 	spin_lock_init(&tiqn->logout_stats.lock);
135 
136 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
137 
138 	idr_preload(GFP_KERNEL);
139 	spin_lock(&tiqn_lock);
140 
141 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
142 	if (ret < 0) {
143 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
144 		spin_unlock(&tiqn_lock);
145 		idr_preload_end();
146 		kfree(tiqn);
147 		return ERR_PTR(ret);
148 	}
149 	tiqn->tiqn_index = ret;
150 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
151 
152 	spin_unlock(&tiqn_lock);
153 	idr_preload_end();
154 
155 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
156 
157 	return tiqn;
158 
159 }
160 
161 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
162 {
163 	/*
164 	 * Wait for accesses to said struct iscsi_tiqn to end.
165 	 */
166 	spin_lock(&tiqn->tiqn_state_lock);
167 	while (tiqn->tiqn_access_count != 0) {
168 		spin_unlock(&tiqn->tiqn_state_lock);
169 		msleep(10);
170 		spin_lock(&tiqn->tiqn_state_lock);
171 	}
172 	spin_unlock(&tiqn->tiqn_state_lock);
173 }
174 
175 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
176 {
177 	/*
178 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
179 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
180 	 * attempts to access this struct iscsi_tiqn will fail from both transport
181 	 * fabric and control code paths.
182 	 */
183 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
184 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
185 		return;
186 	}
187 
188 	iscsit_wait_for_tiqn(tiqn);
189 
190 	spin_lock(&tiqn_lock);
191 	list_del(&tiqn->tiqn_list);
192 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
193 	spin_unlock(&tiqn_lock);
194 
195 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
196 			tiqn->tiqn);
197 	kfree(tiqn);
198 }
199 
200 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
201 {
202 	int ret;
203 	/*
204 	 * Determine if the network portal is accepting storage traffic.
205 	 */
206 	spin_lock_bh(&np->np_thread_lock);
207 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
208 		spin_unlock_bh(&np->np_thread_lock);
209 		return -1;
210 	}
211 	spin_unlock_bh(&np->np_thread_lock);
212 	/*
213 	 * Determine if the portal group is accepting storage traffic.
214 	 */
215 	spin_lock_bh(&tpg->tpg_state_lock);
216 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
217 		spin_unlock_bh(&tpg->tpg_state_lock);
218 		return -1;
219 	}
220 	spin_unlock_bh(&tpg->tpg_state_lock);
221 
222 	/*
223 	 * Here we serialize access across the TIQN+TPG Tuple.
224 	 */
225 	ret = down_interruptible(&tpg->np_login_sem);
226 	if (ret != 0)
227 		return -1;
228 
229 	spin_lock_bh(&tpg->tpg_state_lock);
230 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
231 		spin_unlock_bh(&tpg->tpg_state_lock);
232 		up(&tpg->np_login_sem);
233 		return -1;
234 	}
235 	spin_unlock_bh(&tpg->tpg_state_lock);
236 
237 	return 0;
238 }
239 
240 void iscsit_login_kref_put(struct kref *kref)
241 {
242 	struct iscsi_tpg_np *tpg_np = container_of(kref,
243 				struct iscsi_tpg_np, tpg_np_kref);
244 
245 	complete(&tpg_np->tpg_np_comp);
246 }
247 
248 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
249 		       struct iscsi_tpg_np *tpg_np)
250 {
251 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
252 
253 	up(&tpg->np_login_sem);
254 
255 	if (tpg_np)
256 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
257 
258 	if (tiqn)
259 		iscsit_put_tiqn_for_login(tiqn);
260 
261 	return 0;
262 }
263 
264 bool iscsit_check_np_match(
265 	struct sockaddr_storage *sockaddr,
266 	struct iscsi_np *np,
267 	int network_transport)
268 {
269 	struct sockaddr_in *sock_in, *sock_in_e;
270 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
271 	bool ip_match = false;
272 	u16 port, port_e;
273 
274 	if (sockaddr->ss_family == AF_INET6) {
275 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
276 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
277 
278 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
279 			    &sock_in6_e->sin6_addr.in6_u,
280 			    sizeof(struct in6_addr)))
281 			ip_match = true;
282 
283 		port = ntohs(sock_in6->sin6_port);
284 		port_e = ntohs(sock_in6_e->sin6_port);
285 	} else {
286 		sock_in = (struct sockaddr_in *)sockaddr;
287 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
288 
289 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
290 			ip_match = true;
291 
292 		port = ntohs(sock_in->sin_port);
293 		port_e = ntohs(sock_in_e->sin_port);
294 	}
295 
296 	if (ip_match && (port_e == port) &&
297 	    (np->np_network_transport == network_transport))
298 		return true;
299 
300 	return false;
301 }
302 
303 static struct iscsi_np *iscsit_get_np(
304 	struct sockaddr_storage *sockaddr,
305 	int network_transport)
306 {
307 	struct iscsi_np *np;
308 	bool match;
309 
310 	lockdep_assert_held(&np_lock);
311 
312 	list_for_each_entry(np, &g_np_list, np_list) {
313 		spin_lock_bh(&np->np_thread_lock);
314 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
315 			spin_unlock_bh(&np->np_thread_lock);
316 			continue;
317 		}
318 
319 		match = iscsit_check_np_match(sockaddr, np, network_transport);
320 		if (match) {
321 			/*
322 			 * Increment the np_exports reference count now to
323 			 * prevent iscsit_del_np() below from being called
324 			 * while iscsi_tpg_add_network_portal() is called.
325 			 */
326 			np->np_exports++;
327 			spin_unlock_bh(&np->np_thread_lock);
328 			return np;
329 		}
330 		spin_unlock_bh(&np->np_thread_lock);
331 	}
332 
333 	return NULL;
334 }
335 
336 struct iscsi_np *iscsit_add_np(
337 	struct sockaddr_storage *sockaddr,
338 	int network_transport)
339 {
340 	struct iscsi_np *np;
341 	int ret;
342 
343 	mutex_lock(&np_lock);
344 
345 	/*
346 	 * Locate the existing struct iscsi_np if already active..
347 	 */
348 	np = iscsit_get_np(sockaddr, network_transport);
349 	if (np) {
350 		mutex_unlock(&np_lock);
351 		return np;
352 	}
353 
354 	np = kzalloc(sizeof(*np), GFP_KERNEL);
355 	if (!np) {
356 		mutex_unlock(&np_lock);
357 		return ERR_PTR(-ENOMEM);
358 	}
359 
360 	np->np_flags |= NPF_IP_NETWORK;
361 	np->np_network_transport = network_transport;
362 	spin_lock_init(&np->np_thread_lock);
363 	init_completion(&np->np_restart_comp);
364 	INIT_LIST_HEAD(&np->np_list);
365 
366 	timer_setup(&np->np_login_timer, iscsi_handle_login_thread_timeout, 0);
367 
368 	ret = iscsi_target_setup_login_socket(np, sockaddr);
369 	if (ret != 0) {
370 		kfree(np);
371 		mutex_unlock(&np_lock);
372 		return ERR_PTR(ret);
373 	}
374 
375 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
376 	if (IS_ERR(np->np_thread)) {
377 		pr_err("Unable to create kthread: iscsi_np\n");
378 		ret = PTR_ERR(np->np_thread);
379 		kfree(np);
380 		mutex_unlock(&np_lock);
381 		return ERR_PTR(ret);
382 	}
383 	/*
384 	 * Increment the np_exports reference count now to prevent
385 	 * iscsit_del_np() below from being run while a new call to
386 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
387 	 * active.  We don't need to hold np->np_thread_lock at this
388 	 * point because iscsi_np has not been added to g_np_list yet.
389 	 */
390 	np->np_exports = 1;
391 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
392 
393 	list_add_tail(&np->np_list, &g_np_list);
394 	mutex_unlock(&np_lock);
395 
396 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
397 		&np->np_sockaddr, np->np_transport->name);
398 
399 	return np;
400 }
401 
402 int iscsit_reset_np_thread(
403 	struct iscsi_np *np,
404 	struct iscsi_tpg_np *tpg_np,
405 	struct iscsi_portal_group *tpg,
406 	bool shutdown)
407 {
408 	spin_lock_bh(&np->np_thread_lock);
409 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
410 		spin_unlock_bh(&np->np_thread_lock);
411 		return 0;
412 	}
413 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
414 	atomic_inc(&np->np_reset_count);
415 
416 	if (np->np_thread) {
417 		spin_unlock_bh(&np->np_thread_lock);
418 		send_sig(SIGINT, np->np_thread, 1);
419 		wait_for_completion(&np->np_restart_comp);
420 		spin_lock_bh(&np->np_thread_lock);
421 	}
422 	spin_unlock_bh(&np->np_thread_lock);
423 
424 	if (tpg_np && shutdown) {
425 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
426 
427 		wait_for_completion(&tpg_np->tpg_np_comp);
428 	}
429 
430 	return 0;
431 }
432 
433 static void iscsit_free_np(struct iscsi_np *np)
434 {
435 	if (np->np_socket)
436 		sock_release(np->np_socket);
437 }
438 
439 int iscsit_del_np(struct iscsi_np *np)
440 {
441 	spin_lock_bh(&np->np_thread_lock);
442 	np->np_exports--;
443 	if (np->np_exports) {
444 		np->enabled = true;
445 		spin_unlock_bh(&np->np_thread_lock);
446 		return 0;
447 	}
448 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
449 	spin_unlock_bh(&np->np_thread_lock);
450 
451 	if (np->np_thread) {
452 		/*
453 		 * We need to send the signal to wakeup Linux/Net
454 		 * which may be sleeping in sock_accept()..
455 		 */
456 		send_sig(SIGINT, np->np_thread, 1);
457 		kthread_stop(np->np_thread);
458 		np->np_thread = NULL;
459 	}
460 
461 	np->np_transport->iscsit_free_np(np);
462 
463 	mutex_lock(&np_lock);
464 	list_del(&np->np_list);
465 	mutex_unlock(&np_lock);
466 
467 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
468 		&np->np_sockaddr, np->np_transport->name);
469 
470 	iscsit_put_transport(np->np_transport);
471 	kfree(np);
472 	return 0;
473 }
474 
475 static void iscsit_get_rx_pdu(struct iscsit_conn *);
476 
477 int iscsit_queue_rsp(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
478 {
479 	return iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
480 }
481 EXPORT_SYMBOL(iscsit_queue_rsp);
482 
483 void iscsit_aborted_task(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
484 {
485 	spin_lock_bh(&conn->cmd_lock);
486 	if (!list_empty(&cmd->i_conn_node))
487 		list_del_init(&cmd->i_conn_node);
488 	spin_unlock_bh(&conn->cmd_lock);
489 
490 	__iscsit_free_cmd(cmd, true);
491 }
492 EXPORT_SYMBOL(iscsit_aborted_task);
493 
494 static void iscsit_do_crypto_hash_buf(struct ahash_request *, const void *,
495 				      u32, u32, const void *, void *);
496 static void iscsit_tx_thread_wait_for_tcp(struct iscsit_conn *);
497 
498 static int
499 iscsit_xmit_nondatain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
500 			  const void *data_buf, u32 data_buf_len)
501 {
502 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
503 	struct kvec *iov;
504 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
505 	int ret;
506 
507 	iov = &cmd->iov_misc[0];
508 	iov[niov].iov_base	= cmd->pdu;
509 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
510 
511 	if (conn->conn_ops->HeaderDigest) {
512 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
513 
514 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, hdr,
515 					  ISCSI_HDR_LEN, 0, NULL,
516 					  header_digest);
517 
518 		iov[0].iov_len += ISCSI_CRC_LEN;
519 		tx_size += ISCSI_CRC_LEN;
520 		pr_debug("Attaching CRC32C HeaderDigest"
521 			 " to opcode 0x%x 0x%08x\n",
522 			 hdr->opcode, *header_digest);
523 	}
524 
525 	if (data_buf_len) {
526 		u32 padding = ((-data_buf_len) & 3);
527 
528 		iov[niov].iov_base	= (void *)data_buf;
529 		iov[niov++].iov_len	= data_buf_len;
530 		tx_size += data_buf_len;
531 
532 		if (padding != 0) {
533 			iov[niov].iov_base = &cmd->pad_bytes;
534 			iov[niov++].iov_len = padding;
535 			tx_size += padding;
536 			pr_debug("Attaching %u additional"
537 				 " padding bytes.\n", padding);
538 		}
539 
540 		if (conn->conn_ops->DataDigest) {
541 			iscsit_do_crypto_hash_buf(conn->conn_tx_hash,
542 						  data_buf, data_buf_len,
543 						  padding, &cmd->pad_bytes,
544 						  &cmd->data_crc);
545 
546 			iov[niov].iov_base = &cmd->data_crc;
547 			iov[niov++].iov_len = ISCSI_CRC_LEN;
548 			tx_size += ISCSI_CRC_LEN;
549 			pr_debug("Attached DataDigest for %u"
550 				 " bytes opcode 0x%x, CRC 0x%08x\n",
551 				 data_buf_len, hdr->opcode, cmd->data_crc);
552 		}
553 	}
554 
555 	cmd->iov_misc_count = niov;
556 	cmd->tx_size = tx_size;
557 
558 	ret = iscsit_send_tx_data(cmd, conn, 1);
559 	if (ret < 0) {
560 		iscsit_tx_thread_wait_for_tcp(conn);
561 		return ret;
562 	}
563 
564 	return 0;
565 }
566 
567 static int iscsit_map_iovec(struct iscsit_cmd *cmd, struct kvec *iov, int nvec,
568 			    u32 data_offset, u32 data_length);
569 static void iscsit_unmap_iovec(struct iscsit_cmd *);
570 static u32 iscsit_do_crypto_hash_sg(struct ahash_request *, struct iscsit_cmd *,
571 				    u32, u32, u32, u8 *);
572 static int
573 iscsit_xmit_datain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
574 		       const struct iscsi_datain *datain)
575 {
576 	struct kvec *iov;
577 	u32 iov_count = 0, tx_size = 0;
578 	int ret, iov_ret;
579 
580 	iov = &cmd->iov_data[0];
581 	iov[iov_count].iov_base	= cmd->pdu;
582 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
583 	tx_size += ISCSI_HDR_LEN;
584 
585 	if (conn->conn_ops->HeaderDigest) {
586 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
587 
588 		iscsit_do_crypto_hash_buf(conn->conn_tx_hash, cmd->pdu,
589 					  ISCSI_HDR_LEN, 0, NULL,
590 					  header_digest);
591 
592 		iov[0].iov_len += ISCSI_CRC_LEN;
593 		tx_size += ISCSI_CRC_LEN;
594 
595 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
596 			 *header_digest);
597 	}
598 
599 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[iov_count],
600 				   cmd->orig_iov_data_count - (iov_count + 2),
601 				   datain->offset, datain->length);
602 	if (iov_ret < 0)
603 		return -1;
604 
605 	iov_count += iov_ret;
606 	tx_size += datain->length;
607 
608 	cmd->padding = ((-datain->length) & 3);
609 	if (cmd->padding) {
610 		iov[iov_count].iov_base		= cmd->pad_bytes;
611 		iov[iov_count++].iov_len	= cmd->padding;
612 		tx_size += cmd->padding;
613 
614 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
615 	}
616 
617 	if (conn->conn_ops->DataDigest) {
618 		cmd->data_crc = iscsit_do_crypto_hash_sg(conn->conn_tx_hash,
619 							 cmd, datain->offset,
620 							 datain->length,
621 							 cmd->padding,
622 							 cmd->pad_bytes);
623 
624 		iov[iov_count].iov_base	= &cmd->data_crc;
625 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
626 		tx_size += ISCSI_CRC_LEN;
627 
628 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
629 			 datain->length + cmd->padding, cmd->data_crc);
630 	}
631 
632 	cmd->iov_data_count = iov_count;
633 	cmd->tx_size = tx_size;
634 
635 	ret = iscsit_fe_sendpage_sg(cmd, conn);
636 
637 	iscsit_unmap_iovec(cmd);
638 
639 	if (ret < 0) {
640 		iscsit_tx_thread_wait_for_tcp(conn);
641 		return ret;
642 	}
643 
644 	return 0;
645 }
646 
647 static int iscsit_xmit_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
648 			   struct iscsi_datain_req *dr, const void *buf,
649 			   u32 buf_len)
650 {
651 	if (dr)
652 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
653 	else
654 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
655 }
656 
657 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsit_conn *conn)
658 {
659 	return TARGET_PROT_NORMAL;
660 }
661 
662 static struct iscsit_transport iscsi_target_transport = {
663 	.name			= "iSCSI/TCP",
664 	.transport_type		= ISCSI_TCP,
665 	.rdma_shutdown		= false,
666 	.owner			= NULL,
667 	.iscsit_setup_np	= iscsit_setup_np,
668 	.iscsit_accept_np	= iscsit_accept_np,
669 	.iscsit_free_np		= iscsit_free_np,
670 	.iscsit_get_login_rx	= iscsit_get_login_rx,
671 	.iscsit_put_login_tx	= iscsit_put_login_tx,
672 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
673 	.iscsit_immediate_queue	= iscsit_immediate_queue,
674 	.iscsit_response_queue	= iscsit_response_queue,
675 	.iscsit_queue_data_in	= iscsit_queue_rsp,
676 	.iscsit_queue_status	= iscsit_queue_rsp,
677 	.iscsit_aborted_task	= iscsit_aborted_task,
678 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
679 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
680 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
681 };
682 
683 static int __init iscsi_target_init_module(void)
684 {
685 	int ret = 0, size;
686 
687 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
688 	iscsit_global = kzalloc(sizeof(*iscsit_global), GFP_KERNEL);
689 	if (!iscsit_global)
690 		return -1;
691 
692 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
693 	mutex_init(&auth_id_lock);
694 	idr_init(&tiqn_idr);
695 
696 	ret = target_register_template(&iscsi_ops);
697 	if (ret)
698 		goto out;
699 
700 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
701 	iscsit_global->ts_bitmap = vzalloc(size);
702 	if (!iscsit_global->ts_bitmap)
703 		goto configfs_out;
704 
705 	if (!zalloc_cpumask_var(&iscsit_global->allowed_cpumask, GFP_KERNEL)) {
706 		pr_err("Unable to allocate iscsit_global->allowed_cpumask\n");
707 		goto bitmap_out;
708 	}
709 	cpumask_setall(iscsit_global->allowed_cpumask);
710 
711 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
712 			sizeof(struct iscsi_queue_req),
713 			__alignof__(struct iscsi_queue_req), 0, NULL);
714 	if (!lio_qr_cache) {
715 		pr_err("Unable to kmem_cache_create() for"
716 				" lio_qr_cache\n");
717 		goto cpumask_out;
718 	}
719 
720 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
721 			sizeof(struct iscsi_datain_req),
722 			__alignof__(struct iscsi_datain_req), 0, NULL);
723 	if (!lio_dr_cache) {
724 		pr_err("Unable to kmem_cache_create() for"
725 				" lio_dr_cache\n");
726 		goto qr_out;
727 	}
728 
729 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
730 			sizeof(struct iscsi_ooo_cmdsn),
731 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
732 	if (!lio_ooo_cache) {
733 		pr_err("Unable to kmem_cache_create() for"
734 				" lio_ooo_cache\n");
735 		goto dr_out;
736 	}
737 
738 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
739 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
740 			0, NULL);
741 	if (!lio_r2t_cache) {
742 		pr_err("Unable to kmem_cache_create() for"
743 				" lio_r2t_cache\n");
744 		goto ooo_out;
745 	}
746 
747 	iscsit_register_transport(&iscsi_target_transport);
748 
749 	if (iscsit_load_discovery_tpg() < 0)
750 		goto r2t_out;
751 
752 	return ret;
753 r2t_out:
754 	iscsit_unregister_transport(&iscsi_target_transport);
755 	kmem_cache_destroy(lio_r2t_cache);
756 ooo_out:
757 	kmem_cache_destroy(lio_ooo_cache);
758 dr_out:
759 	kmem_cache_destroy(lio_dr_cache);
760 qr_out:
761 	kmem_cache_destroy(lio_qr_cache);
762 cpumask_out:
763 	free_cpumask_var(iscsit_global->allowed_cpumask);
764 bitmap_out:
765 	vfree(iscsit_global->ts_bitmap);
766 configfs_out:
767 	/* XXX: this probably wants it to be it's own unwind step.. */
768 	if (iscsit_global->discovery_tpg)
769 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
770 	target_unregister_template(&iscsi_ops);
771 out:
772 	kfree(iscsit_global);
773 	return -ENOMEM;
774 }
775 
776 static void __exit iscsi_target_cleanup_module(void)
777 {
778 	iscsit_release_discovery_tpg();
779 	iscsit_unregister_transport(&iscsi_target_transport);
780 	kmem_cache_destroy(lio_qr_cache);
781 	kmem_cache_destroy(lio_dr_cache);
782 	kmem_cache_destroy(lio_ooo_cache);
783 	kmem_cache_destroy(lio_r2t_cache);
784 
785 	/*
786 	 * Shutdown discovery sessions and disable discovery TPG
787 	 */
788 	if (iscsit_global->discovery_tpg)
789 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
790 
791 	target_unregister_template(&iscsi_ops);
792 
793 	free_cpumask_var(iscsit_global->allowed_cpumask);
794 	vfree(iscsit_global->ts_bitmap);
795 	kfree(iscsit_global);
796 }
797 
798 int iscsit_add_reject(
799 	struct iscsit_conn *conn,
800 	u8 reason,
801 	unsigned char *buf)
802 {
803 	struct iscsit_cmd *cmd;
804 
805 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
806 	if (!cmd)
807 		return -1;
808 
809 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
810 	cmd->reject_reason = reason;
811 
812 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
813 	if (!cmd->buf_ptr) {
814 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
815 		iscsit_free_cmd(cmd, false);
816 		return -1;
817 	}
818 
819 	spin_lock_bh(&conn->cmd_lock);
820 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
821 	spin_unlock_bh(&conn->cmd_lock);
822 
823 	cmd->i_state = ISTATE_SEND_REJECT;
824 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
825 
826 	return -1;
827 }
828 EXPORT_SYMBOL(iscsit_add_reject);
829 
830 static int iscsit_add_reject_from_cmd(
831 	struct iscsit_cmd *cmd,
832 	u8 reason,
833 	bool add_to_conn,
834 	unsigned char *buf)
835 {
836 	struct iscsit_conn *conn;
837 	const bool do_put = cmd->se_cmd.se_tfo != NULL;
838 
839 	if (!cmd->conn) {
840 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
841 				cmd->init_task_tag);
842 		return -1;
843 	}
844 	conn = cmd->conn;
845 
846 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
847 	cmd->reject_reason = reason;
848 
849 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
850 	if (!cmd->buf_ptr) {
851 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
852 		iscsit_free_cmd(cmd, false);
853 		return -1;
854 	}
855 
856 	if (add_to_conn) {
857 		spin_lock_bh(&conn->cmd_lock);
858 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
859 		spin_unlock_bh(&conn->cmd_lock);
860 	}
861 
862 	cmd->i_state = ISTATE_SEND_REJECT;
863 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
864 	/*
865 	 * Perform the kref_put now if se_cmd has already been setup by
866 	 * scsit_setup_scsi_cmd()
867 	 */
868 	if (do_put) {
869 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
870 		target_put_sess_cmd(&cmd->se_cmd);
871 	}
872 	return -1;
873 }
874 
875 static int iscsit_add_reject_cmd(struct iscsit_cmd *cmd, u8 reason,
876 				 unsigned char *buf)
877 {
878 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
879 }
880 
881 int iscsit_reject_cmd(struct iscsit_cmd *cmd, u8 reason, unsigned char *buf)
882 {
883 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
884 }
885 EXPORT_SYMBOL(iscsit_reject_cmd);
886 
887 /*
888  * Map some portion of the allocated scatterlist to an iovec, suitable for
889  * kernel sockets to copy data in/out.
890  */
891 static int iscsit_map_iovec(struct iscsit_cmd *cmd, struct kvec *iov, int nvec,
892 			    u32 data_offset, u32 data_length)
893 {
894 	u32 i = 0, orig_data_length = data_length;
895 	struct scatterlist *sg;
896 	unsigned int page_off;
897 
898 	/*
899 	 * We know each entry in t_data_sg contains a page.
900 	 */
901 	u32 ent = data_offset / PAGE_SIZE;
902 
903 	if (!data_length)
904 		return 0;
905 
906 	if (ent >= cmd->se_cmd.t_data_nents) {
907 		pr_err("Initial page entry out-of-bounds\n");
908 		goto overflow;
909 	}
910 
911 	sg = &cmd->se_cmd.t_data_sg[ent];
912 	page_off = (data_offset % PAGE_SIZE);
913 
914 	cmd->first_data_sg = sg;
915 	cmd->first_data_sg_off = page_off;
916 
917 	while (data_length) {
918 		u32 cur_len;
919 
920 		if (WARN_ON_ONCE(!sg || i >= nvec))
921 			goto overflow;
922 
923 		cur_len = min_t(u32, data_length, sg->length - page_off);
924 
925 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
926 		iov[i].iov_len = cur_len;
927 
928 		data_length -= cur_len;
929 		page_off = 0;
930 		sg = sg_next(sg);
931 		i++;
932 	}
933 
934 	cmd->kmapped_nents = i;
935 
936 	return i;
937 
938 overflow:
939 	pr_err("offset %d + length %d overflow; %d/%d; sg-list:\n",
940 	       data_offset, orig_data_length, i, nvec);
941 	for_each_sg(cmd->se_cmd.t_data_sg, sg,
942 		    cmd->se_cmd.t_data_nents, i) {
943 		pr_err("[%d] off %d len %d\n",
944 		       i, sg->offset, sg->length);
945 	}
946 	return -1;
947 }
948 
949 static void iscsit_unmap_iovec(struct iscsit_cmd *cmd)
950 {
951 	u32 i;
952 	struct scatterlist *sg;
953 
954 	sg = cmd->first_data_sg;
955 
956 	for (i = 0; i < cmd->kmapped_nents; i++)
957 		kunmap(sg_page(&sg[i]));
958 }
959 
960 static void iscsit_ack_from_expstatsn(struct iscsit_conn *conn, u32 exp_statsn)
961 {
962 	LIST_HEAD(ack_list);
963 	struct iscsit_cmd *cmd, *cmd_p;
964 
965 	conn->exp_statsn = exp_statsn;
966 
967 	if (conn->sess->sess_ops->RDMAExtensions)
968 		return;
969 
970 	spin_lock_bh(&conn->cmd_lock);
971 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
972 		spin_lock(&cmd->istate_lock);
973 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
974 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
975 			cmd->i_state = ISTATE_REMOVE;
976 			spin_unlock(&cmd->istate_lock);
977 			list_move_tail(&cmd->i_conn_node, &ack_list);
978 			continue;
979 		}
980 		spin_unlock(&cmd->istate_lock);
981 	}
982 	spin_unlock_bh(&conn->cmd_lock);
983 
984 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
985 		list_del_init(&cmd->i_conn_node);
986 		iscsit_free_cmd(cmd, false);
987 	}
988 }
989 
990 static int iscsit_allocate_iovecs(struct iscsit_cmd *cmd)
991 {
992 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
993 
994 	iov_count += ISCSI_IOV_DATA_BUFFER;
995 	cmd->iov_data = kcalloc(iov_count, sizeof(*cmd->iov_data), GFP_KERNEL);
996 	if (!cmd->iov_data)
997 		return -ENOMEM;
998 
999 	cmd->orig_iov_data_count = iov_count;
1000 	return 0;
1001 }
1002 
1003 int iscsit_setup_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1004 			  unsigned char *buf)
1005 {
1006 	int data_direction, payload_length;
1007 	struct iscsi_ecdb_ahdr *ecdb_ahdr;
1008 	struct iscsi_scsi_req *hdr;
1009 	int iscsi_task_attr;
1010 	unsigned char *cdb;
1011 	int sam_task_attr;
1012 
1013 	atomic_long_inc(&conn->sess->cmd_pdus);
1014 
1015 	hdr			= (struct iscsi_scsi_req *) buf;
1016 	payload_length		= ntoh24(hdr->dlength);
1017 
1018 	/* FIXME; Add checks for AdditionalHeaderSegment */
1019 
1020 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1021 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1022 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1023 				" not set. Bad iSCSI Initiator.\n");
1024 		return iscsit_add_reject_cmd(cmd,
1025 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1026 	}
1027 
1028 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1029 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1030 		/*
1031 		 * From RFC-3720 Section 10.3.1:
1032 		 *
1033 		 * "Either or both of R and W MAY be 1 when either the
1034 		 *  Expected Data Transfer Length and/or Bidirectional Read
1035 		 *  Expected Data Transfer Length are 0"
1036 		 *
1037 		 * For this case, go ahead and clear the unnecssary bits
1038 		 * to avoid any confusion with ->data_direction.
1039 		 */
1040 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1041 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1042 
1043 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1044 			" set when Expected Data Transfer Length is 0 for"
1045 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1046 	}
1047 
1048 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1049 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1050 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1051 			" MUST be set if Expected Data Transfer Length is not 0."
1052 			" Bad iSCSI Initiator\n");
1053 		return iscsit_add_reject_cmd(cmd,
1054 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1055 	}
1056 
1057 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1058 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1059 		pr_err("Bidirectional operations not supported!\n");
1060 		return iscsit_add_reject_cmd(cmd,
1061 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1062 	}
1063 
1064 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1065 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1066 				" Scsi Command PDU.\n");
1067 		return iscsit_add_reject_cmd(cmd,
1068 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1069 	}
1070 
1071 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1072 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1073 			" protocol error.\n", payload_length);
1074 		return iscsit_add_reject_cmd(cmd,
1075 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1076 	}
1077 
1078 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1079 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1080 		pr_err("Expected Data Transfer Length and Length of"
1081 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1082 			" bit is not set protocol error\n");
1083 		return iscsit_add_reject_cmd(cmd,
1084 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1085 	}
1086 
1087 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1088 		pr_err("DataSegmentLength: %u is greater than"
1089 			" EDTL: %u, protocol error.\n", payload_length,
1090 				hdr->data_length);
1091 		return iscsit_add_reject_cmd(cmd,
1092 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1093 	}
1094 
1095 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1096 		pr_err("DataSegmentLength: %u is greater than"
1097 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1098 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1099 		return iscsit_add_reject_cmd(cmd,
1100 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1101 	}
1102 
1103 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1104 		pr_err("DataSegmentLength: %u is greater than"
1105 			" FirstBurstLength: %u, protocol error.\n",
1106 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1107 		return iscsit_add_reject_cmd(cmd,
1108 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1109 	}
1110 
1111 	cdb = hdr->cdb;
1112 
1113 	if (hdr->hlength) {
1114 		ecdb_ahdr = (struct iscsi_ecdb_ahdr *) (hdr + 1);
1115 		if (ecdb_ahdr->ahstype != ISCSI_AHSTYPE_CDB) {
1116 			pr_err("Additional Header Segment type %d not supported!\n",
1117 			       ecdb_ahdr->ahstype);
1118 			return iscsit_add_reject_cmd(cmd,
1119 				ISCSI_REASON_CMD_NOT_SUPPORTED, buf);
1120 		}
1121 
1122 		cdb = kmalloc(be16_to_cpu(ecdb_ahdr->ahslength) + 15,
1123 			      GFP_KERNEL);
1124 		if (cdb == NULL)
1125 			return iscsit_add_reject_cmd(cmd,
1126 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1127 		memcpy(cdb, hdr->cdb, ISCSI_CDB_SIZE);
1128 		memcpy(cdb + ISCSI_CDB_SIZE, ecdb_ahdr->ecdb,
1129 		       be16_to_cpu(ecdb_ahdr->ahslength) - 1);
1130 	}
1131 
1132 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1133 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1134 			  DMA_NONE;
1135 
1136 	cmd->data_direction = data_direction;
1137 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1138 	/*
1139 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1140 	 */
1141 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1142 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1143 		sam_task_attr = TCM_SIMPLE_TAG;
1144 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1145 		sam_task_attr = TCM_ORDERED_TAG;
1146 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1147 		sam_task_attr = TCM_HEAD_TAG;
1148 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1149 		sam_task_attr = TCM_ACA_TAG;
1150 	else {
1151 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1152 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1153 		sam_task_attr = TCM_SIMPLE_TAG;
1154 	}
1155 
1156 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1157 	cmd->i_state		= ISTATE_NEW_CMD;
1158 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1159 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1160 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1161 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1162 	if (cmd->unsolicited_data)
1163 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1164 
1165 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1166 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1167 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1168 	else
1169 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1170 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1171 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1172 	cmd->first_burst_len	= payload_length;
1173 
1174 	if (!conn->sess->sess_ops->RDMAExtensions &&
1175 	     cmd->data_direction == DMA_FROM_DEVICE) {
1176 		struct iscsi_datain_req *dr;
1177 
1178 		dr = iscsit_allocate_datain_req();
1179 		if (!dr) {
1180 			if (cdb != hdr->cdb)
1181 				kfree(cdb);
1182 			return iscsit_add_reject_cmd(cmd,
1183 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1184 		}
1185 
1186 		iscsit_attach_datain_req(cmd, dr);
1187 	}
1188 
1189 	/*
1190 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1191 	 */
1192 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
1193 			 conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1194 			 cmd->data_direction, sam_task_attr,
1195 			 cmd->sense_buffer + 2, scsilun_to_int(&hdr->lun));
1196 
1197 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1198 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1199 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1200 		conn->cid);
1201 
1202 	target_get_sess_cmd(&cmd->se_cmd, true);
1203 
1204 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1205 	cmd->sense_reason = target_cmd_init_cdb(&cmd->se_cmd, cdb,
1206 						GFP_KERNEL);
1207 
1208 	if (cdb != hdr->cdb)
1209 		kfree(cdb);
1210 
1211 	if (cmd->sense_reason) {
1212 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1213 			return iscsit_add_reject_cmd(cmd,
1214 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1215 		}
1216 
1217 		goto attach_cmd;
1218 	}
1219 
1220 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd);
1221 	if (cmd->sense_reason)
1222 		goto attach_cmd;
1223 
1224 	cmd->sense_reason = target_cmd_parse_cdb(&cmd->se_cmd);
1225 	if (cmd->sense_reason)
1226 		goto attach_cmd;
1227 
1228 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1229 		return iscsit_add_reject_cmd(cmd,
1230 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1231 	}
1232 
1233 attach_cmd:
1234 	spin_lock_bh(&conn->cmd_lock);
1235 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1236 	spin_unlock_bh(&conn->cmd_lock);
1237 	/*
1238 	 * Check if we need to delay processing because of ALUA
1239 	 * Active/NonOptimized primary access state..
1240 	 */
1241 	core_alua_check_nonop_delay(&cmd->se_cmd);
1242 
1243 	return 0;
1244 }
1245 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1246 
1247 void iscsit_set_unsolicited_dataout(struct iscsit_cmd *cmd)
1248 {
1249 	iscsit_set_dataout_sequence_values(cmd);
1250 
1251 	spin_lock_bh(&cmd->dataout_timeout_lock);
1252 	iscsit_start_dataout_timer(cmd, cmd->conn);
1253 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1254 }
1255 EXPORT_SYMBOL(iscsit_set_unsolicited_dataout);
1256 
1257 int iscsit_process_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1258 			    struct iscsi_scsi_req *hdr)
1259 {
1260 	int cmdsn_ret = 0;
1261 	/*
1262 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1263 	 * the Immediate Bit is not set, and no Immediate
1264 	 * Data is attached.
1265 	 *
1266 	 * A PDU/CmdSN carrying Immediate Data can only
1267 	 * be processed after the DataCRC has passed.
1268 	 * If the DataCRC fails, the CmdSN MUST NOT
1269 	 * be acknowledged. (See below)
1270 	 */
1271 	if (!cmd->immediate_data) {
1272 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1273 					(unsigned char *)hdr, hdr->cmdsn);
1274 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1275 			return -1;
1276 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1277 			target_put_sess_cmd(&cmd->se_cmd);
1278 			return 0;
1279 		}
1280 	}
1281 
1282 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1283 
1284 	/*
1285 	 * If no Immediate Data is attached, it's OK to return now.
1286 	 */
1287 	if (!cmd->immediate_data) {
1288 		if (!cmd->sense_reason && cmd->unsolicited_data)
1289 			iscsit_set_unsolicited_dataout(cmd);
1290 		if (!cmd->sense_reason)
1291 			return 0;
1292 
1293 		target_put_sess_cmd(&cmd->se_cmd);
1294 		return 0;
1295 	}
1296 
1297 	/*
1298 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1299 	 * execution.  These exceptions are processed in CmdSN order using
1300 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1301 	 */
1302 	if (cmd->sense_reason)
1303 		return 1;
1304 	/*
1305 	 * Call directly into transport_generic_new_cmd() to perform
1306 	 * the backend memory allocation.
1307 	 */
1308 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1309 	if (cmd->sense_reason)
1310 		return 1;
1311 
1312 	return 0;
1313 }
1314 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1315 
1316 static int
1317 iscsit_get_immediate_data(struct iscsit_cmd *cmd, struct iscsi_scsi_req *hdr,
1318 			  bool dump_payload)
1319 {
1320 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1321 	int rc;
1322 
1323 	/*
1324 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1325 	 */
1326 	if (dump_payload) {
1327 		u32 length = min(cmd->se_cmd.data_length - cmd->write_data_done,
1328 				 cmd->first_burst_len);
1329 
1330 		pr_debug("Dumping min(%d - %d, %d) = %d bytes of immediate data\n",
1331 			 cmd->se_cmd.data_length, cmd->write_data_done,
1332 			 cmd->first_burst_len, length);
1333 		rc = iscsit_dump_data_payload(cmd->conn, length, 1);
1334 		pr_debug("Finished dumping immediate data\n");
1335 		if (rc < 0)
1336 			immed_ret = IMMEDIATE_DATA_CANNOT_RECOVER;
1337 	} else {
1338 		immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1339 							 cmd->first_burst_len);
1340 	}
1341 
1342 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1343 		/*
1344 		 * A PDU/CmdSN carrying Immediate Data passed
1345 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1346 		 * Immediate Bit is not set.
1347 		 */
1348 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1349 					(unsigned char *)hdr, hdr->cmdsn);
1350 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1351 			return -1;
1352 
1353 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1354 			target_put_sess_cmd(&cmd->se_cmd);
1355 
1356 			return 0;
1357 		} else if (cmd->unsolicited_data)
1358 			iscsit_set_unsolicited_dataout(cmd);
1359 
1360 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1361 		/*
1362 		 * Immediate Data failed DataCRC and ERL>=1,
1363 		 * silently drop this PDU and let the initiator
1364 		 * plug the CmdSN gap.
1365 		 *
1366 		 * FIXME: Send Unsolicited NOPIN with reserved
1367 		 * TTT here to help the initiator figure out
1368 		 * the missing CmdSN, although they should be
1369 		 * intelligent enough to determine the missing
1370 		 * CmdSN and issue a retry to plug the sequence.
1371 		 */
1372 		cmd->i_state = ISTATE_REMOVE;
1373 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1374 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1375 		return -1;
1376 
1377 	return 0;
1378 }
1379 
1380 static int
1381 iscsit_handle_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1382 			   unsigned char *buf)
1383 {
1384 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1385 	int rc, immed_data;
1386 	bool dump_payload = false;
1387 
1388 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1389 	if (rc < 0)
1390 		return 0;
1391 	/*
1392 	 * Allocation iovecs needed for struct socket operations for
1393 	 * traditional iSCSI block I/O.
1394 	 */
1395 	if (iscsit_allocate_iovecs(cmd) < 0) {
1396 		return iscsit_reject_cmd(cmd,
1397 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1398 	}
1399 	immed_data = cmd->immediate_data;
1400 
1401 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1402 	if (rc < 0)
1403 		return rc;
1404 	else if (rc > 0)
1405 		dump_payload = true;
1406 
1407 	if (!immed_data)
1408 		return 0;
1409 
1410 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1411 }
1412 
1413 static u32 iscsit_do_crypto_hash_sg(
1414 	struct ahash_request *hash,
1415 	struct iscsit_cmd *cmd,
1416 	u32 data_offset,
1417 	u32 data_length,
1418 	u32 padding,
1419 	u8 *pad_bytes)
1420 {
1421 	u32 data_crc;
1422 	struct scatterlist *sg;
1423 	unsigned int page_off;
1424 
1425 	crypto_ahash_init(hash);
1426 
1427 	sg = cmd->first_data_sg;
1428 	page_off = cmd->first_data_sg_off;
1429 
1430 	if (data_length && page_off) {
1431 		struct scatterlist first_sg;
1432 		u32 len = min_t(u32, data_length, sg->length - page_off);
1433 
1434 		sg_init_table(&first_sg, 1);
1435 		sg_set_page(&first_sg, sg_page(sg), len, sg->offset + page_off);
1436 
1437 		ahash_request_set_crypt(hash, &first_sg, NULL, len);
1438 		crypto_ahash_update(hash);
1439 
1440 		data_length -= len;
1441 		sg = sg_next(sg);
1442 	}
1443 
1444 	while (data_length) {
1445 		u32 cur_len = min_t(u32, data_length, sg->length);
1446 
1447 		ahash_request_set_crypt(hash, sg, NULL, cur_len);
1448 		crypto_ahash_update(hash);
1449 
1450 		data_length -= cur_len;
1451 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1452 		sg = sg_next(sg);
1453 	}
1454 
1455 	if (padding) {
1456 		struct scatterlist pad_sg;
1457 
1458 		sg_init_one(&pad_sg, pad_bytes, padding);
1459 		ahash_request_set_crypt(hash, &pad_sg, (u8 *)&data_crc,
1460 					padding);
1461 		crypto_ahash_finup(hash);
1462 	} else {
1463 		ahash_request_set_crypt(hash, NULL, (u8 *)&data_crc, 0);
1464 		crypto_ahash_final(hash);
1465 	}
1466 
1467 	return data_crc;
1468 }
1469 
1470 static void iscsit_do_crypto_hash_buf(struct ahash_request *hash,
1471 	const void *buf, u32 payload_length, u32 padding,
1472 	const void *pad_bytes, void *data_crc)
1473 {
1474 	struct scatterlist sg[2];
1475 
1476 	sg_init_table(sg, ARRAY_SIZE(sg));
1477 	sg_set_buf(sg, buf, payload_length);
1478 	if (padding)
1479 		sg_set_buf(sg + 1, pad_bytes, padding);
1480 
1481 	ahash_request_set_crypt(hash, sg, data_crc, payload_length + padding);
1482 
1483 	crypto_ahash_digest(hash);
1484 }
1485 
1486 int
1487 __iscsit_check_dataout_hdr(struct iscsit_conn *conn, void *buf,
1488 			   struct iscsit_cmd *cmd, u32 payload_length,
1489 			   bool *success)
1490 {
1491 	struct iscsi_data *hdr = buf;
1492 	struct se_cmd *se_cmd;
1493 	int rc;
1494 
1495 	/* iSCSI write */
1496 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1497 
1498 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1499 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1500 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1501 		payload_length, conn->cid);
1502 
1503 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1504 		pr_err("Command ITT: 0x%08x received DataOUT after"
1505 			" last DataOUT received, dumping payload\n",
1506 			cmd->init_task_tag);
1507 		return iscsit_dump_data_payload(conn, payload_length, 1);
1508 	}
1509 
1510 	if (cmd->data_direction != DMA_TO_DEVICE) {
1511 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1512 			" NON-WRITE command.\n", cmd->init_task_tag);
1513 		return iscsit_dump_data_payload(conn, payload_length, 1);
1514 	}
1515 	se_cmd = &cmd->se_cmd;
1516 	iscsit_mod_dataout_timer(cmd);
1517 
1518 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1519 		pr_err("DataOut Offset: %u, Length %u greater than iSCSI Command EDTL %u, protocol error.\n",
1520 		       be32_to_cpu(hdr->offset), payload_length,
1521 		       cmd->se_cmd.data_length);
1522 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1523 	}
1524 
1525 	if (cmd->unsolicited_data) {
1526 		int dump_unsolicited_data = 0;
1527 
1528 		if (conn->sess->sess_ops->InitialR2T) {
1529 			pr_err("Received unexpected unsolicited data"
1530 				" while InitialR2T=Yes, protocol error.\n");
1531 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1532 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1533 			return -1;
1534 		}
1535 		/*
1536 		 * Special case for dealing with Unsolicited DataOUT
1537 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1538 		 * failures;
1539 		 */
1540 
1541 		/* Something's amiss if we're not in WRITE_PENDING state... */
1542 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1543 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1544 			dump_unsolicited_data = 1;
1545 
1546 		if (dump_unsolicited_data) {
1547 			/*
1548 			 * Check if a delayed TASK_ABORTED status needs to
1549 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1550 			 * received with the unsolicited data out.
1551 			 */
1552 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1553 				iscsit_stop_dataout_timer(cmd);
1554 
1555 			return iscsit_dump_data_payload(conn, payload_length, 1);
1556 		}
1557 	} else {
1558 		/*
1559 		 * For the normal solicited data path:
1560 		 *
1561 		 * Check for a delayed TASK_ABORTED status and dump any
1562 		 * incoming data out payload if one exists.  Also, when the
1563 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1564 		 * data out sequence, we decrement outstanding_r2ts.  Once
1565 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1566 		 * TASK_ABORTED status.
1567 		 */
1568 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1569 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL &&
1570 			    --cmd->outstanding_r2ts < 1)
1571 				iscsit_stop_dataout_timer(cmd);
1572 
1573 			return iscsit_dump_data_payload(conn, payload_length, 1);
1574 		}
1575 	}
1576 	/*
1577 	 * Perform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1578 	 * within-command recovery checks before receiving the payload.
1579 	 */
1580 	rc = iscsit_check_pre_dataout(cmd, buf);
1581 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1582 		return 0;
1583 	else if (rc == DATAOUT_CANNOT_RECOVER)
1584 		return -1;
1585 	*success = true;
1586 	return 0;
1587 }
1588 EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
1589 
1590 int
1591 iscsit_check_dataout_hdr(struct iscsit_conn *conn, void *buf,
1592 			 struct iscsit_cmd **out_cmd)
1593 {
1594 	struct iscsi_data *hdr = buf;
1595 	struct iscsit_cmd *cmd;
1596 	u32 payload_length = ntoh24(hdr->dlength);
1597 	int rc;
1598 	bool success = false;
1599 
1600 	if (!payload_length) {
1601 		pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
1602 		return 0;
1603 	}
1604 
1605 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1606 		pr_err_ratelimited("DataSegmentLength: %u is greater than"
1607 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1608 			conn->conn_ops->MaxXmitDataSegmentLength);
1609 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
1610 	}
1611 
1612 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
1613 	if (!cmd)
1614 		return 0;
1615 
1616 	rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
1617 
1618 	if (success)
1619 		*out_cmd = cmd;
1620 
1621 	return rc;
1622 }
1623 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1624 
1625 static int
1626 iscsit_get_dataout(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1627 		   struct iscsi_data *hdr)
1628 {
1629 	struct kvec *iov;
1630 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1631 	u32 payload_length;
1632 	int iov_ret, data_crc_failed = 0;
1633 
1634 	payload_length = min_t(u32, cmd->se_cmd.data_length,
1635 			       ntoh24(hdr->dlength));
1636 	rx_size += payload_length;
1637 	iov = &cmd->iov_data[0];
1638 
1639 	iov_ret = iscsit_map_iovec(cmd, iov, cmd->orig_iov_data_count - 2,
1640 				   be32_to_cpu(hdr->offset), payload_length);
1641 	if (iov_ret < 0)
1642 		return -1;
1643 
1644 	iov_count += iov_ret;
1645 
1646 	padding = ((-payload_length) & 3);
1647 	if (padding != 0) {
1648 		iov[iov_count].iov_base	= cmd->pad_bytes;
1649 		iov[iov_count++].iov_len = padding;
1650 		rx_size += padding;
1651 		pr_debug("Receiving %u padding bytes.\n", padding);
1652 	}
1653 
1654 	if (conn->conn_ops->DataDigest) {
1655 		iov[iov_count].iov_base = &checksum;
1656 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1657 		rx_size += ISCSI_CRC_LEN;
1658 	}
1659 
1660 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
1661 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1662 
1663 	iscsit_unmap_iovec(cmd);
1664 
1665 	if (rx_got != rx_size)
1666 		return -1;
1667 
1668 	if (conn->conn_ops->DataDigest) {
1669 		u32 data_crc;
1670 
1671 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
1672 						    be32_to_cpu(hdr->offset),
1673 						    payload_length, padding,
1674 						    cmd->pad_bytes);
1675 
1676 		if (checksum != data_crc) {
1677 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1678 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1679 				" does not match computed 0x%08x\n",
1680 				hdr->itt, hdr->offset, payload_length,
1681 				hdr->datasn, checksum, data_crc);
1682 			data_crc_failed = 1;
1683 		} else {
1684 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1685 				" %u bytes of Data Out\n", checksum,
1686 				payload_length);
1687 		}
1688 	}
1689 
1690 	return data_crc_failed;
1691 }
1692 
1693 int
1694 iscsit_check_dataout_payload(struct iscsit_cmd *cmd, struct iscsi_data *hdr,
1695 			     bool data_crc_failed)
1696 {
1697 	struct iscsit_conn *conn = cmd->conn;
1698 	int rc, ooo_cmdsn;
1699 	/*
1700 	 * Increment post receive data and CRC values or perform
1701 	 * within-command recovery.
1702 	 */
1703 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1704 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1705 		return 0;
1706 	else if (rc == DATAOUT_SEND_R2T) {
1707 		iscsit_set_dataout_sequence_values(cmd);
1708 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1709 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1710 		/*
1711 		 * Handle extra special case for out of order
1712 		 * Unsolicited Data Out.
1713 		 */
1714 		spin_lock_bh(&cmd->istate_lock);
1715 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1716 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1717 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1718 		spin_unlock_bh(&cmd->istate_lock);
1719 
1720 		iscsit_stop_dataout_timer(cmd);
1721 		if (ooo_cmdsn)
1722 			return 0;
1723 		target_execute_cmd(&cmd->se_cmd);
1724 		return 0;
1725 	} else /* DATAOUT_CANNOT_RECOVER */
1726 		return -1;
1727 
1728 	return 0;
1729 }
1730 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1731 
1732 static int iscsit_handle_data_out(struct iscsit_conn *conn, unsigned char *buf)
1733 {
1734 	struct iscsit_cmd *cmd = NULL;
1735 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1736 	int rc;
1737 	bool data_crc_failed = false;
1738 
1739 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1740 	if (rc < 0)
1741 		return 0;
1742 	else if (!cmd)
1743 		return 0;
1744 
1745 	rc = iscsit_get_dataout(conn, cmd, hdr);
1746 	if (rc < 0)
1747 		return rc;
1748 	else if (rc > 0)
1749 		data_crc_failed = true;
1750 
1751 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1752 }
1753 
1754 int iscsit_setup_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1755 			 struct iscsi_nopout *hdr)
1756 {
1757 	u32 payload_length = ntoh24(hdr->dlength);
1758 
1759 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1760 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1761 		if (!cmd)
1762 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1763 						 (unsigned char *)hdr);
1764 
1765 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1766 					 (unsigned char *)hdr);
1767 	}
1768 
1769 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1770 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1771 			" not set, protocol error.\n");
1772 		if (!cmd)
1773 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1774 						 (unsigned char *)hdr);
1775 
1776 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1777 					 (unsigned char *)hdr);
1778 	}
1779 
1780 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1781 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1782 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1783 			" error.\n", payload_length,
1784 			conn->conn_ops->MaxXmitDataSegmentLength);
1785 		if (!cmd)
1786 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1787 						 (unsigned char *)hdr);
1788 
1789 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1790 					 (unsigned char *)hdr);
1791 	}
1792 
1793 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1794 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1795 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1796 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1797 		payload_length);
1798 	/*
1799 	 * This is not a response to a Unsolicited NopIN, which means
1800 	 * it can either be a NOPOUT ping request (with a valid ITT),
1801 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1802 	 * Either way, make sure we allocate an struct iscsit_cmd, as both
1803 	 * can contain ping data.
1804 	 */
1805 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1806 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1807 		cmd->i_state		= ISTATE_SEND_NOPIN;
1808 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1809 						1 : 0);
1810 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1811 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1812 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1813 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1814 		cmd->data_direction	= DMA_NONE;
1815 	}
1816 
1817 	return 0;
1818 }
1819 EXPORT_SYMBOL(iscsit_setup_nop_out);
1820 
1821 int iscsit_process_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1822 			   struct iscsi_nopout *hdr)
1823 {
1824 	struct iscsit_cmd *cmd_p = NULL;
1825 	int cmdsn_ret = 0;
1826 	/*
1827 	 * Initiator is expecting a NopIN ping reply..
1828 	 */
1829 	if (hdr->itt != RESERVED_ITT) {
1830 		if (!cmd)
1831 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1832 						(unsigned char *)hdr);
1833 
1834 		spin_lock_bh(&conn->cmd_lock);
1835 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1836 		spin_unlock_bh(&conn->cmd_lock);
1837 
1838 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1839 
1840 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1841 			iscsit_add_cmd_to_response_queue(cmd, conn,
1842 							 cmd->i_state);
1843 			return 0;
1844 		}
1845 
1846 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1847 				(unsigned char *)hdr, hdr->cmdsn);
1848                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1849 			return 0;
1850 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1851 			return -1;
1852 
1853 		return 0;
1854 	}
1855 	/*
1856 	 * This was a response to a unsolicited NOPIN ping.
1857 	 */
1858 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1859 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1860 		if (!cmd_p)
1861 			return -EINVAL;
1862 
1863 		iscsit_stop_nopin_response_timer(conn);
1864 
1865 		cmd_p->i_state = ISTATE_REMOVE;
1866 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1867 
1868 		iscsit_start_nopin_timer(conn);
1869 		return 0;
1870 	}
1871 	/*
1872 	 * Otherwise, initiator is not expecting a NOPIN is response.
1873 	 * Just ignore for now.
1874 	 */
1875 
1876 	if (cmd)
1877 		iscsit_free_cmd(cmd, false);
1878 
1879         return 0;
1880 }
1881 EXPORT_SYMBOL(iscsit_process_nop_out);
1882 
1883 static int iscsit_handle_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1884 				 unsigned char *buf)
1885 {
1886 	unsigned char *ping_data = NULL;
1887 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1888 	struct kvec *iov = NULL;
1889 	u32 payload_length = ntoh24(hdr->dlength);
1890 	int ret;
1891 
1892 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1893 	if (ret < 0)
1894 		return 0;
1895 	/*
1896 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1897 	 */
1898 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1899 		u32 checksum, data_crc, padding = 0;
1900 		int niov = 0, rx_got, rx_size = payload_length;
1901 
1902 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1903 		if (!ping_data) {
1904 			ret = -1;
1905 			goto out;
1906 		}
1907 
1908 		iov = &cmd->iov_misc[0];
1909 		iov[niov].iov_base	= ping_data;
1910 		iov[niov++].iov_len	= payload_length;
1911 
1912 		padding = ((-payload_length) & 3);
1913 		if (padding != 0) {
1914 			pr_debug("Receiving %u additional bytes"
1915 				" for padding.\n", padding);
1916 			iov[niov].iov_base	= &cmd->pad_bytes;
1917 			iov[niov++].iov_len	= padding;
1918 			rx_size += padding;
1919 		}
1920 		if (conn->conn_ops->DataDigest) {
1921 			iov[niov].iov_base	= &checksum;
1922 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1923 			rx_size += ISCSI_CRC_LEN;
1924 		}
1925 
1926 		WARN_ON_ONCE(niov > ARRAY_SIZE(cmd->iov_misc));
1927 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1928 		if (rx_got != rx_size) {
1929 			ret = -1;
1930 			goto out;
1931 		}
1932 
1933 		if (conn->conn_ops->DataDigest) {
1934 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, ping_data,
1935 						  payload_length, padding,
1936 						  cmd->pad_bytes, &data_crc);
1937 
1938 			if (checksum != data_crc) {
1939 				pr_err("Ping data CRC32C DataDigest"
1940 				" 0x%08x does not match computed 0x%08x\n",
1941 					checksum, data_crc);
1942 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1943 					pr_err("Unable to recover from"
1944 					" NOPOUT Ping DataCRC failure while in"
1945 						" ERL=0.\n");
1946 					ret = -1;
1947 					goto out;
1948 				} else {
1949 					/*
1950 					 * Silently drop this PDU and let the
1951 					 * initiator plug the CmdSN gap.
1952 					 */
1953 					pr_debug("Dropping NOPOUT"
1954 					" Command CmdSN: 0x%08x due to"
1955 					" DataCRC error.\n", hdr->cmdsn);
1956 					ret = 0;
1957 					goto out;
1958 				}
1959 			} else {
1960 				pr_debug("Got CRC32C DataDigest"
1961 				" 0x%08x for %u bytes of ping data.\n",
1962 					checksum, payload_length);
1963 			}
1964 		}
1965 
1966 		ping_data[payload_length] = '\0';
1967 		/*
1968 		 * Attach ping data to struct iscsit_cmd->buf_ptr.
1969 		 */
1970 		cmd->buf_ptr = ping_data;
1971 		cmd->buf_ptr_size = payload_length;
1972 
1973 		pr_debug("Got %u bytes of NOPOUT ping"
1974 			" data.\n", payload_length);
1975 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1976 	}
1977 
1978 	return iscsit_process_nop_out(conn, cmd, hdr);
1979 out:
1980 	if (cmd)
1981 		iscsit_free_cmd(cmd, false);
1982 
1983 	kfree(ping_data);
1984 	return ret;
1985 }
1986 
1987 static enum tcm_tmreq_table iscsit_convert_tmf(u8 iscsi_tmf)
1988 {
1989 	switch (iscsi_tmf) {
1990 	case ISCSI_TM_FUNC_ABORT_TASK:
1991 		return TMR_ABORT_TASK;
1992 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1993 		return TMR_ABORT_TASK_SET;
1994 	case ISCSI_TM_FUNC_CLEAR_ACA:
1995 		return TMR_CLEAR_ACA;
1996 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1997 		return TMR_CLEAR_TASK_SET;
1998 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1999 		return TMR_LUN_RESET;
2000 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2001 		return TMR_TARGET_WARM_RESET;
2002 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2003 		return TMR_TARGET_COLD_RESET;
2004 	default:
2005 		return TMR_UNKNOWN;
2006 	}
2007 }
2008 
2009 int
2010 iscsit_handle_task_mgt_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2011 			   unsigned char *buf)
2012 {
2013 	struct se_tmr_req *se_tmr;
2014 	struct iscsi_tmr_req *tmr_req;
2015 	struct iscsi_tm *hdr;
2016 	int out_of_order_cmdsn = 0, ret;
2017 	u8 function, tcm_function = TMR_UNKNOWN;
2018 
2019 	hdr			= (struct iscsi_tm *) buf;
2020 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
2021 	function = hdr->flags;
2022 
2023 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
2024 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
2025 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
2026 		hdr->rtt, hdr->refcmdsn, conn->cid);
2027 
2028 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
2029 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2030 	     hdr->rtt != RESERVED_ITT)) {
2031 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
2032 		hdr->rtt = RESERVED_ITT;
2033 	}
2034 
2035 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
2036 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2037 		pr_err("Task Management Request TASK_REASSIGN not"
2038 			" issued as immediate command, bad iSCSI Initiator"
2039 				"implementation\n");
2040 		return iscsit_add_reject_cmd(cmd,
2041 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
2042 	}
2043 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
2044 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
2045 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
2046 
2047 	cmd->data_direction = DMA_NONE;
2048 	cmd->tmr_req = kzalloc(sizeof(*cmd->tmr_req), GFP_KERNEL);
2049 	if (!cmd->tmr_req) {
2050 		return iscsit_add_reject_cmd(cmd,
2051 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
2052 					     buf);
2053 	}
2054 
2055 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
2056 			  conn->sess->se_sess, 0, DMA_NONE,
2057 			  TCM_SIMPLE_TAG, cmd->sense_buffer + 2,
2058 			  scsilun_to_int(&hdr->lun));
2059 
2060 	target_get_sess_cmd(&cmd->se_cmd, true);
2061 
2062 	/*
2063 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
2064 	 * LIO-Target $FABRIC_MOD
2065 	 */
2066 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2067 		tcm_function = iscsit_convert_tmf(function);
2068 		if (tcm_function == TMR_UNKNOWN) {
2069 			pr_err("Unknown iSCSI TMR Function:"
2070 			       " 0x%02x\n", function);
2071 			return iscsit_add_reject_cmd(cmd,
2072 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2073 		}
2074 	}
2075 	ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
2076 				 GFP_KERNEL);
2077 	if (ret < 0)
2078 		return iscsit_add_reject_cmd(cmd,
2079 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2080 
2081 	cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2082 
2083 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2084 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2085 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2086 	cmd->init_task_tag	= hdr->itt;
2087 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2088 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2089 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2090 	se_tmr			= cmd->se_cmd.se_tmr_req;
2091 	tmr_req			= cmd->tmr_req;
2092 	/*
2093 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2094 	 */
2095 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2096 		ret = transport_lookup_tmr_lun(&cmd->se_cmd);
2097 		if (ret < 0) {
2098 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2099 			goto attach;
2100 		}
2101 	}
2102 
2103 	switch (function) {
2104 	case ISCSI_TM_FUNC_ABORT_TASK:
2105 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2106 		if (se_tmr->response)
2107 			goto attach;
2108 		break;
2109 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2110 	case ISCSI_TM_FUNC_CLEAR_ACA:
2111 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2112 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2113 		break;
2114 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2115 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2116 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2117 			goto attach;
2118 		}
2119 		break;
2120 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2121 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2122 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2123 			goto attach;
2124 		}
2125 		break;
2126 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2127 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2128 		/*
2129 		 * Perform sanity checks on the ExpDataSN only if the
2130 		 * TASK_REASSIGN was successful.
2131 		 */
2132 		if (se_tmr->response)
2133 			break;
2134 
2135 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2136 			return iscsit_add_reject_cmd(cmd,
2137 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2138 		break;
2139 	default:
2140 		pr_err("Unknown TMR function: 0x%02x, protocol"
2141 			" error.\n", function);
2142 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2143 		goto attach;
2144 	}
2145 
2146 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2147 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2148 		se_tmr->call_transport = 1;
2149 attach:
2150 	spin_lock_bh(&conn->cmd_lock);
2151 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2152 	spin_unlock_bh(&conn->cmd_lock);
2153 
2154 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2155 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2156 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP) {
2157 			out_of_order_cmdsn = 1;
2158 		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2159 			target_put_sess_cmd(&cmd->se_cmd);
2160 			return 0;
2161 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2162 			return -1;
2163 		}
2164 	}
2165 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2166 
2167 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2168 		return 0;
2169 	/*
2170 	 * Found the referenced task, send to transport for processing.
2171 	 */
2172 	if (se_tmr->call_transport)
2173 		return transport_generic_handle_tmr(&cmd->se_cmd);
2174 
2175 	/*
2176 	 * Could not find the referenced LUN, task, or Task Management
2177 	 * command not authorized or supported.  Change state and
2178 	 * let the tx_thread send the response.
2179 	 *
2180 	 * For connection recovery, this is also the default action for
2181 	 * TMR TASK_REASSIGN.
2182 	 */
2183 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2184 	target_put_sess_cmd(&cmd->se_cmd);
2185 	return 0;
2186 }
2187 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2188 
2189 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2190 int
2191 iscsit_setup_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2192 		      struct iscsi_text *hdr)
2193 {
2194 	u32 payload_length = ntoh24(hdr->dlength);
2195 
2196 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2197 		pr_err("Unable to accept text parameter length: %u"
2198 			"greater than MaxXmitDataSegmentLength %u.\n",
2199 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2200 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2201 					 (unsigned char *)hdr);
2202 	}
2203 
2204 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2205 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2206 		pr_err("Multi sequence text commands currently not supported\n");
2207 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2208 					(unsigned char *)hdr);
2209 	}
2210 
2211 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2212 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2213 		hdr->exp_statsn, payload_length);
2214 
2215 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2216 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2217 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2218 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2219 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2220 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2221 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2222 	cmd->data_direction	= DMA_NONE;
2223 	kfree(cmd->text_in_ptr);
2224 	cmd->text_in_ptr	= NULL;
2225 
2226 	return 0;
2227 }
2228 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2229 
2230 int
2231 iscsit_process_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2232 			struct iscsi_text *hdr)
2233 {
2234 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2235 	int cmdsn_ret;
2236 
2237 	if (!text_in) {
2238 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2239 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2240 			pr_err("Unable to locate text_in buffer for sendtargets"
2241 			       " discovery\n");
2242 			goto reject;
2243 		}
2244 		goto empty_sendtargets;
2245 	}
2246 	if (strncmp("SendTargets=", text_in, 12) != 0) {
2247 		pr_err("Received Text Data that is not"
2248 			" SendTargets, cannot continue.\n");
2249 		goto reject;
2250 	}
2251 	/* '=' confirmed in strncmp */
2252 	text_ptr = strchr(text_in, '=');
2253 	BUG_ON(!text_ptr);
2254 	if (!strncmp("=All", text_ptr, 5)) {
2255 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2256 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2257 		   !strncmp("=eui.", text_ptr, 5)) {
2258 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2259 	} else {
2260 		pr_err("Unable to locate valid SendTargets%s value\n",
2261 		       text_ptr);
2262 		goto reject;
2263 	}
2264 
2265 	spin_lock_bh(&conn->cmd_lock);
2266 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2267 	spin_unlock_bh(&conn->cmd_lock);
2268 
2269 empty_sendtargets:
2270 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2271 
2272 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2273 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2274 				(unsigned char *)hdr, hdr->cmdsn);
2275 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2276 			return -1;
2277 
2278 		return 0;
2279 	}
2280 
2281 	return iscsit_execute_cmd(cmd, 0);
2282 
2283 reject:
2284 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2285 				 (unsigned char *)hdr);
2286 }
2287 EXPORT_SYMBOL(iscsit_process_text_cmd);
2288 
2289 static int
2290 iscsit_handle_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2291 		       unsigned char *buf)
2292 {
2293 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2294 	char *text_in = NULL;
2295 	u32 payload_length = ntoh24(hdr->dlength);
2296 	int rx_size, rc;
2297 
2298 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2299 	if (rc < 0)
2300 		return 0;
2301 
2302 	rx_size = payload_length;
2303 	if (payload_length) {
2304 		u32 checksum = 0, data_crc = 0;
2305 		u32 padding = 0;
2306 		int niov = 0, rx_got;
2307 		struct kvec iov[2];
2308 
2309 		rx_size = ALIGN(payload_length, 4);
2310 		text_in = kzalloc(rx_size, GFP_KERNEL);
2311 		if (!text_in)
2312 			goto reject;
2313 
2314 		cmd->text_in_ptr = text_in;
2315 
2316 		memset(iov, 0, sizeof(iov));
2317 		iov[niov].iov_base	= text_in;
2318 		iov[niov++].iov_len	= rx_size;
2319 
2320 		padding = rx_size - payload_length;
2321 		if (padding)
2322 			pr_debug("Receiving %u additional bytes"
2323 					" for padding.\n", padding);
2324 		if (conn->conn_ops->DataDigest) {
2325 			iov[niov].iov_base	= &checksum;
2326 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2327 			rx_size += ISCSI_CRC_LEN;
2328 		}
2329 
2330 		WARN_ON_ONCE(niov > ARRAY_SIZE(iov));
2331 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2332 		if (rx_got != rx_size)
2333 			goto reject;
2334 
2335 		if (conn->conn_ops->DataDigest) {
2336 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash,
2337 						  text_in, rx_size, 0, NULL,
2338 						  &data_crc);
2339 
2340 			if (checksum != data_crc) {
2341 				pr_err("Text data CRC32C DataDigest"
2342 					" 0x%08x does not match computed"
2343 					" 0x%08x\n", checksum, data_crc);
2344 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2345 					pr_err("Unable to recover from"
2346 					" Text Data digest failure while in"
2347 						" ERL=0.\n");
2348 					goto reject;
2349 				} else {
2350 					/*
2351 					 * Silently drop this PDU and let the
2352 					 * initiator plug the CmdSN gap.
2353 					 */
2354 					pr_debug("Dropping Text"
2355 					" Command CmdSN: 0x%08x due to"
2356 					" DataCRC error.\n", hdr->cmdsn);
2357 					kfree(text_in);
2358 					return 0;
2359 				}
2360 			} else {
2361 				pr_debug("Got CRC32C DataDigest"
2362 					" 0x%08x for %u bytes of text data.\n",
2363 						checksum, payload_length);
2364 			}
2365 		}
2366 		text_in[payload_length - 1] = '\0';
2367 		pr_debug("Successfully read %d bytes of text"
2368 				" data.\n", payload_length);
2369 	}
2370 
2371 	return iscsit_process_text_cmd(conn, cmd, hdr);
2372 
2373 reject:
2374 	kfree(cmd->text_in_ptr);
2375 	cmd->text_in_ptr = NULL;
2376 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2377 }
2378 
2379 int iscsit_logout_closesession(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2380 {
2381 	struct iscsit_conn *conn_p;
2382 	struct iscsit_session *sess = conn->sess;
2383 
2384 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2385 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2386 
2387 	atomic_set(&sess->session_logout, 1);
2388 	atomic_set(&conn->conn_logout_remove, 1);
2389 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2390 
2391 	iscsit_inc_conn_usage_count(conn);
2392 	iscsit_inc_session_usage_count(sess);
2393 
2394 	spin_lock_bh(&sess->conn_lock);
2395 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2396 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2397 			continue;
2398 
2399 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2400 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2401 	}
2402 	spin_unlock_bh(&sess->conn_lock);
2403 
2404 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2405 
2406 	return 0;
2407 }
2408 
2409 int iscsit_logout_closeconnection(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2410 {
2411 	struct iscsit_conn *l_conn;
2412 	struct iscsit_session *sess = conn->sess;
2413 
2414 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2415 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2416 
2417 	/*
2418 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2419 	 * can arrive on a connection with a differing CID.
2420 	 */
2421 	if (conn->cid == cmd->logout_cid) {
2422 		spin_lock_bh(&conn->state_lock);
2423 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2424 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2425 
2426 		atomic_set(&conn->conn_logout_remove, 1);
2427 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2428 		iscsit_inc_conn_usage_count(conn);
2429 
2430 		spin_unlock_bh(&conn->state_lock);
2431 	} else {
2432 		/*
2433 		 * Handle all different cid CLOSECONNECTION requests in
2434 		 * iscsit_logout_post_handler_diffcid() as to give enough
2435 		 * time for any non immediate command's CmdSN to be
2436 		 * acknowledged on the connection in question.
2437 		 *
2438 		 * Here we simply make sure the CID is still around.
2439 		 */
2440 		l_conn = iscsit_get_conn_from_cid(sess,
2441 				cmd->logout_cid);
2442 		if (!l_conn) {
2443 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2444 			iscsit_add_cmd_to_response_queue(cmd, conn,
2445 					cmd->i_state);
2446 			return 0;
2447 		}
2448 
2449 		iscsit_dec_conn_usage_count(l_conn);
2450 	}
2451 
2452 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2453 
2454 	return 0;
2455 }
2456 
2457 int iscsit_logout_removeconnforrecovery(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2458 {
2459 	struct iscsit_session *sess = conn->sess;
2460 
2461 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2462 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2463 
2464 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2465 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2466 			" while ERL!=2.\n");
2467 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2468 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2469 		return 0;
2470 	}
2471 
2472 	if (conn->cid == cmd->logout_cid) {
2473 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2474 			" with CID: %hu on CID: %hu, implementation error.\n",
2475 				cmd->logout_cid, conn->cid);
2476 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2477 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2478 		return 0;
2479 	}
2480 
2481 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2482 
2483 	return 0;
2484 }
2485 
2486 int
2487 iscsit_handle_logout_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2488 			unsigned char *buf)
2489 {
2490 	int cmdsn_ret, logout_remove = 0;
2491 	u8 reason_code = 0;
2492 	struct iscsi_logout *hdr;
2493 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2494 
2495 	hdr			= (struct iscsi_logout *) buf;
2496 	reason_code		= (hdr->flags & 0x7f);
2497 
2498 	if (tiqn) {
2499 		spin_lock(&tiqn->logout_stats.lock);
2500 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2501 			tiqn->logout_stats.normal_logouts++;
2502 		else
2503 			tiqn->logout_stats.abnormal_logouts++;
2504 		spin_unlock(&tiqn->logout_stats.lock);
2505 	}
2506 
2507 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2508 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2509 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2510 		hdr->cid, conn->cid);
2511 
2512 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2513 		pr_err("Received logout request on connection that"
2514 			" is not in logged in state, ignoring request.\n");
2515 		iscsit_free_cmd(cmd, false);
2516 		return 0;
2517 	}
2518 
2519 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2520 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2521 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2522 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2523 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2524 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2525 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2526 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2527 	cmd->logout_reason      = reason_code;
2528 	cmd->data_direction     = DMA_NONE;
2529 
2530 	/*
2531 	 * We need to sleep in these cases (by returning 1) until the Logout
2532 	 * Response gets sent in the tx thread.
2533 	 */
2534 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2535 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2536 	    be16_to_cpu(hdr->cid) == conn->cid))
2537 		logout_remove = 1;
2538 
2539 	spin_lock_bh(&conn->cmd_lock);
2540 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2541 	spin_unlock_bh(&conn->cmd_lock);
2542 
2543 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2544 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2545 
2546 	/*
2547 	 * Immediate commands are executed, well, immediately.
2548 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2549 	 */
2550 	if (cmd->immediate_cmd) {
2551 		int ret = iscsit_execute_cmd(cmd, 0);
2552 
2553 		if (ret < 0)
2554 			return ret;
2555 	} else {
2556 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2557 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2558 			logout_remove = 0;
2559 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2560 			return -1;
2561 	}
2562 
2563 	return logout_remove;
2564 }
2565 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2566 
2567 int iscsit_handle_snack(
2568 	struct iscsit_conn *conn,
2569 	unsigned char *buf)
2570 {
2571 	struct iscsi_snack *hdr;
2572 
2573 	hdr			= (struct iscsi_snack *) buf;
2574 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2575 
2576 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2577 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2578 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2579 			hdr->begrun, hdr->runlength, conn->cid);
2580 
2581 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2582 		pr_err("Initiator sent SNACK request while in"
2583 			" ErrorRecoveryLevel=0.\n");
2584 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2585 					 buf);
2586 	}
2587 	/*
2588 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2589 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2590 	 */
2591 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2592 	case 0:
2593 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2594 			hdr->itt,
2595 			be32_to_cpu(hdr->ttt),
2596 			be32_to_cpu(hdr->begrun),
2597 			be32_to_cpu(hdr->runlength));
2598 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2599 		return iscsit_handle_status_snack(conn, hdr->itt,
2600 			be32_to_cpu(hdr->ttt),
2601 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2602 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2603 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2604 			be32_to_cpu(hdr->begrun),
2605 			be32_to_cpu(hdr->runlength));
2606 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2607 		/* FIXME: Support R-Data SNACK */
2608 		pr_err("R-Data SNACK Not Supported.\n");
2609 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2610 					 buf);
2611 	default:
2612 		pr_err("Unknown SNACK type 0x%02x, protocol"
2613 			" error.\n", hdr->flags & 0x0f);
2614 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2615 					 buf);
2616 	}
2617 
2618 	return 0;
2619 }
2620 EXPORT_SYMBOL(iscsit_handle_snack);
2621 
2622 static void iscsit_rx_thread_wait_for_tcp(struct iscsit_conn *conn)
2623 {
2624 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2625 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2626 		wait_for_completion_interruptible_timeout(
2627 					&conn->rx_half_close_comp,
2628 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2629 	}
2630 }
2631 
2632 static int iscsit_handle_immediate_data(
2633 	struct iscsit_cmd *cmd,
2634 	struct iscsi_scsi_req *hdr,
2635 	u32 length)
2636 {
2637 	int iov_ret, rx_got = 0, rx_size = 0;
2638 	u32 checksum, iov_count = 0, padding = 0;
2639 	struct iscsit_conn *conn = cmd->conn;
2640 	struct kvec *iov;
2641 	void *overflow_buf = NULL;
2642 
2643 	BUG_ON(cmd->write_data_done > cmd->se_cmd.data_length);
2644 	rx_size = min(cmd->se_cmd.data_length - cmd->write_data_done, length);
2645 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data,
2646 				   cmd->orig_iov_data_count - 2,
2647 				   cmd->write_data_done, rx_size);
2648 	if (iov_ret < 0)
2649 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2650 
2651 	iov_count = iov_ret;
2652 	iov = &cmd->iov_data[0];
2653 	if (rx_size < length) {
2654 		/*
2655 		 * Special case: length of immediate data exceeds the data
2656 		 * buffer size derived from the CDB.
2657 		 */
2658 		overflow_buf = kmalloc(length - rx_size, GFP_KERNEL);
2659 		if (!overflow_buf) {
2660 			iscsit_unmap_iovec(cmd);
2661 			return IMMEDIATE_DATA_CANNOT_RECOVER;
2662 		}
2663 		cmd->overflow_buf = overflow_buf;
2664 		iov[iov_count].iov_base = overflow_buf;
2665 		iov[iov_count].iov_len = length - rx_size;
2666 		iov_count++;
2667 		rx_size = length;
2668 	}
2669 
2670 	padding = ((-length) & 3);
2671 	if (padding != 0) {
2672 		iov[iov_count].iov_base	= cmd->pad_bytes;
2673 		iov[iov_count++].iov_len = padding;
2674 		rx_size += padding;
2675 	}
2676 
2677 	if (conn->conn_ops->DataDigest) {
2678 		iov[iov_count].iov_base		= &checksum;
2679 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2680 		rx_size += ISCSI_CRC_LEN;
2681 	}
2682 
2683 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
2684 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2685 
2686 	iscsit_unmap_iovec(cmd);
2687 
2688 	if (rx_got != rx_size) {
2689 		iscsit_rx_thread_wait_for_tcp(conn);
2690 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2691 	}
2692 
2693 	if (conn->conn_ops->DataDigest) {
2694 		u32 data_crc;
2695 
2696 		data_crc = iscsit_do_crypto_hash_sg(conn->conn_rx_hash, cmd,
2697 						    cmd->write_data_done, length, padding,
2698 						    cmd->pad_bytes);
2699 
2700 		if (checksum != data_crc) {
2701 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2702 				" does not match computed 0x%08x\n", checksum,
2703 				data_crc);
2704 
2705 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2706 				pr_err("Unable to recover from"
2707 					" Immediate Data digest failure while"
2708 					" in ERL=0.\n");
2709 				iscsit_reject_cmd(cmd,
2710 						ISCSI_REASON_DATA_DIGEST_ERROR,
2711 						(unsigned char *)hdr);
2712 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2713 			} else {
2714 				iscsit_reject_cmd(cmd,
2715 						ISCSI_REASON_DATA_DIGEST_ERROR,
2716 						(unsigned char *)hdr);
2717 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2718 			}
2719 		} else {
2720 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2721 				" %u bytes of Immediate Data\n", checksum,
2722 				length);
2723 		}
2724 	}
2725 
2726 	cmd->write_data_done += length;
2727 
2728 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2729 		spin_lock_bh(&cmd->istate_lock);
2730 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2731 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2732 		spin_unlock_bh(&cmd->istate_lock);
2733 	}
2734 
2735 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2736 }
2737 
2738 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2739 	with active network interface */
2740 static void iscsit_build_conn_drop_async_message(struct iscsit_conn *conn)
2741 {
2742 	struct iscsit_cmd *cmd;
2743 	struct iscsit_conn *conn_p;
2744 	bool found = false;
2745 
2746 	lockdep_assert_held(&conn->sess->conn_lock);
2747 
2748 	/*
2749 	 * Only send a Asynchronous Message on connections whos network
2750 	 * interface is still functional.
2751 	 */
2752 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2753 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2754 			iscsit_inc_conn_usage_count(conn_p);
2755 			found = true;
2756 			break;
2757 		}
2758 	}
2759 
2760 	if (!found)
2761 		return;
2762 
2763 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2764 	if (!cmd) {
2765 		iscsit_dec_conn_usage_count(conn_p);
2766 		return;
2767 	}
2768 
2769 	cmd->logout_cid = conn->cid;
2770 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2771 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2772 
2773 	spin_lock_bh(&conn_p->cmd_lock);
2774 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2775 	spin_unlock_bh(&conn_p->cmd_lock);
2776 
2777 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2778 	iscsit_dec_conn_usage_count(conn_p);
2779 }
2780 
2781 static int iscsit_send_conn_drop_async_message(
2782 	struct iscsit_cmd *cmd,
2783 	struct iscsit_conn *conn)
2784 {
2785 	struct iscsi_async *hdr;
2786 
2787 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2788 
2789 	hdr			= (struct iscsi_async *) cmd->pdu;
2790 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2791 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2792 	cmd->init_task_tag	= RESERVED_ITT;
2793 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2794 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2795 	cmd->stat_sn		= conn->stat_sn++;
2796 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2797 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2798 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2799 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2800 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2801 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2802 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2803 
2804 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2805 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2806 			cmd->logout_cid, conn->cid);
2807 
2808 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2809 }
2810 
2811 static void iscsit_tx_thread_wait_for_tcp(struct iscsit_conn *conn)
2812 {
2813 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2814 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2815 		wait_for_completion_interruptible_timeout(
2816 					&conn->tx_half_close_comp,
2817 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2818 	}
2819 }
2820 
2821 void
2822 iscsit_build_datain_pdu(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2823 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2824 			bool set_statsn)
2825 {
2826 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2827 	hdr->flags		= datain->flags;
2828 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2829 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2830 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2831 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2832 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2833 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2834 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2835 		}
2836 	}
2837 	hton24(hdr->dlength, datain->length);
2838 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2839 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2840 				(struct scsi_lun *)&hdr->lun);
2841 	else
2842 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2843 
2844 	hdr->itt		= cmd->init_task_tag;
2845 
2846 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2847 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2848 	else
2849 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2850 	if (set_statsn)
2851 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2852 	else
2853 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2854 
2855 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2856 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2857 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2858 	hdr->offset		= cpu_to_be32(datain->offset);
2859 
2860 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2861 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2862 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2863 		ntohl(hdr->offset), datain->length, conn->cid);
2864 }
2865 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2866 
2867 static int iscsit_send_datain(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2868 {
2869 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2870 	struct iscsi_datain datain;
2871 	struct iscsi_datain_req *dr;
2872 	int eodr = 0, ret;
2873 	bool set_statsn = false;
2874 
2875 	memset(&datain, 0, sizeof(struct iscsi_datain));
2876 	dr = iscsit_get_datain_values(cmd, &datain);
2877 	if (!dr) {
2878 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2879 				cmd->init_task_tag);
2880 		return -1;
2881 	}
2882 	/*
2883 	 * Be paranoid and double check the logic for now.
2884 	 */
2885 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2886 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2887 			" datain.length: %u exceeds cmd->data_length: %u\n",
2888 			cmd->init_task_tag, datain.offset, datain.length,
2889 			cmd->se_cmd.data_length);
2890 		return -1;
2891 	}
2892 
2893 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2894 	/*
2895 	 * Special case for successfully execution w/ both DATAIN
2896 	 * and Sense Data.
2897 	 */
2898 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2899 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2900 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2901 	else {
2902 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2903 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2904 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2905 			cmd->stat_sn = conn->stat_sn++;
2906 			set_statsn = true;
2907 		} else if (dr->dr_complete ==
2908 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2909 			set_statsn = true;
2910 	}
2911 
2912 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2913 
2914 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2915 	if (ret < 0)
2916 		return ret;
2917 
2918 	if (dr->dr_complete) {
2919 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2920 				2 : 1;
2921 		iscsit_free_datain_req(cmd, dr);
2922 	}
2923 
2924 	return eodr;
2925 }
2926 
2927 int
2928 iscsit_build_logout_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2929 			struct iscsi_logout_rsp *hdr)
2930 {
2931 	struct iscsit_conn *logout_conn = NULL;
2932 	struct iscsi_conn_recovery *cr = NULL;
2933 	struct iscsit_session *sess = conn->sess;
2934 	/*
2935 	 * The actual shutting down of Sessions and/or Connections
2936 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2937 	 * is done in scsi_logout_post_handler().
2938 	 */
2939 	switch (cmd->logout_reason) {
2940 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2941 		pr_debug("iSCSI session logout successful, setting"
2942 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2943 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2944 		break;
2945 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2946 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2947 			break;
2948 		/*
2949 		 * For CLOSECONNECTION logout requests carrying
2950 		 * a matching logout CID -> local CID, the reference
2951 		 * for the local CID will have been incremented in
2952 		 * iscsi_logout_closeconnection().
2953 		 *
2954 		 * For CLOSECONNECTION logout requests carrying
2955 		 * a different CID than the connection it arrived
2956 		 * on, the connection responding to cmd->logout_cid
2957 		 * is stopped in iscsit_logout_post_handler_diffcid().
2958 		 */
2959 
2960 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2961 			" successful.\n", cmd->logout_cid, conn->cid);
2962 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2963 		break;
2964 	case ISCSI_LOGOUT_REASON_RECOVERY:
2965 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2966 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2967 			break;
2968 		/*
2969 		 * If the connection is still active from our point of view
2970 		 * force connection recovery to occur.
2971 		 */
2972 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2973 				cmd->logout_cid);
2974 		if (logout_conn) {
2975 			iscsit_connection_reinstatement_rcfr(logout_conn);
2976 			iscsit_dec_conn_usage_count(logout_conn);
2977 		}
2978 
2979 		cr = iscsit_get_inactive_connection_recovery_entry(
2980 				conn->sess, cmd->logout_cid);
2981 		if (!cr) {
2982 			pr_err("Unable to locate CID: %hu for"
2983 			" REMOVECONNFORRECOVERY Logout Request.\n",
2984 				cmd->logout_cid);
2985 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2986 			break;
2987 		}
2988 
2989 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2990 
2991 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2992 			" for recovery for CID: %hu on CID: %hu successful.\n",
2993 				cmd->logout_cid, conn->cid);
2994 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2995 		break;
2996 	default:
2997 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2998 				cmd->logout_reason);
2999 		return -1;
3000 	}
3001 
3002 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
3003 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3004 	hdr->response		= cmd->logout_response;
3005 	hdr->itt		= cmd->init_task_tag;
3006 	cmd->stat_sn		= conn->stat_sn++;
3007 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3008 
3009 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3010 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3011 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3012 
3013 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
3014 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
3015 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
3016 		cmd->logout_cid, conn->cid);
3017 
3018 	return 0;
3019 }
3020 EXPORT_SYMBOL(iscsit_build_logout_rsp);
3021 
3022 static int
3023 iscsit_send_logout(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3024 {
3025 	int rc;
3026 
3027 	rc = iscsit_build_logout_rsp(cmd, conn,
3028 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
3029 	if (rc < 0)
3030 		return rc;
3031 
3032 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3033 }
3034 
3035 void
3036 iscsit_build_nopin_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3037 		       struct iscsi_nopin *hdr, bool nopout_response)
3038 {
3039 	hdr->opcode		= ISCSI_OP_NOOP_IN;
3040 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3041         hton24(hdr->dlength, cmd->buf_ptr_size);
3042 	if (nopout_response)
3043 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
3044 	hdr->itt		= cmd->init_task_tag;
3045 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
3046 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
3047 				  conn->stat_sn;
3048 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3049 
3050 	if (nopout_response)
3051 		iscsit_increment_maxcmdsn(cmd, conn->sess);
3052 
3053 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3054 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3055 
3056 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
3057 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
3058 		"Solicited" : "Unsolicited", cmd->init_task_tag,
3059 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
3060 }
3061 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
3062 
3063 /*
3064  *	Unsolicited NOPIN, either requesting a response or not.
3065  */
3066 static int iscsit_send_unsolicited_nopin(
3067 	struct iscsit_cmd *cmd,
3068 	struct iscsit_conn *conn,
3069 	int want_response)
3070 {
3071 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3072 	int ret;
3073 
3074 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3075 
3076 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3077 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3078 
3079 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3080 	if (ret < 0)
3081 		return ret;
3082 
3083 	spin_lock_bh(&cmd->istate_lock);
3084 	cmd->i_state = want_response ?
3085 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3086 	spin_unlock_bh(&cmd->istate_lock);
3087 
3088 	return 0;
3089 }
3090 
3091 static int
3092 iscsit_send_nopin(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3093 {
3094 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3095 
3096 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3097 
3098 	/*
3099 	 * NOPOUT Ping Data is attached to struct iscsit_cmd->buf_ptr.
3100 	 * NOPOUT DataSegmentLength is at struct iscsit_cmd->buf_ptr_size.
3101 	 */
3102 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3103 
3104 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3105 						     cmd->buf_ptr,
3106 						     cmd->buf_ptr_size);
3107 }
3108 
3109 static int iscsit_send_r2t(
3110 	struct iscsit_cmd *cmd,
3111 	struct iscsit_conn *conn)
3112 {
3113 	struct iscsi_r2t *r2t;
3114 	struct iscsi_r2t_rsp *hdr;
3115 	int ret;
3116 
3117 	r2t = iscsit_get_r2t_from_list(cmd);
3118 	if (!r2t)
3119 		return -1;
3120 
3121 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3122 	memset(hdr, 0, ISCSI_HDR_LEN);
3123 	hdr->opcode		= ISCSI_OP_R2T;
3124 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3125 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3126 			(struct scsi_lun *)&hdr->lun);
3127 	hdr->itt		= cmd->init_task_tag;
3128 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3129 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3130 	else
3131 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3132 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3133 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3134 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3135 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3136 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3137 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3138 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3139 
3140 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3141 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3142 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3143 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3144 			r2t->offset, r2t->xfer_len, conn->cid);
3145 
3146 	spin_lock_bh(&cmd->r2t_lock);
3147 	r2t->sent_r2t = 1;
3148 	spin_unlock_bh(&cmd->r2t_lock);
3149 
3150 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3151 	if (ret < 0) {
3152 		return ret;
3153 	}
3154 
3155 	spin_lock_bh(&cmd->dataout_timeout_lock);
3156 	iscsit_start_dataout_timer(cmd, conn);
3157 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3158 
3159 	return 0;
3160 }
3161 
3162 /*
3163  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3164  *		connection recovery.
3165  */
3166 int iscsit_build_r2ts_for_cmd(
3167 	struct iscsit_conn *conn,
3168 	struct iscsit_cmd *cmd,
3169 	bool recovery)
3170 {
3171 	int first_r2t = 1;
3172 	u32 offset = 0, xfer_len = 0;
3173 
3174 	spin_lock_bh(&cmd->r2t_lock);
3175 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3176 		spin_unlock_bh(&cmd->r2t_lock);
3177 		return 0;
3178 	}
3179 
3180 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3181 	    !recovery)
3182 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3183 
3184 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3185 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3186 			offset = cmd->r2t_offset;
3187 
3188 			if (first_r2t && recovery) {
3189 				int new_data_end = offset +
3190 					conn->sess->sess_ops->MaxBurstLength -
3191 					cmd->next_burst_len;
3192 
3193 				if (new_data_end > cmd->se_cmd.data_length)
3194 					xfer_len = cmd->se_cmd.data_length - offset;
3195 				else
3196 					xfer_len =
3197 						conn->sess->sess_ops->MaxBurstLength -
3198 						cmd->next_burst_len;
3199 			} else {
3200 				int new_data_end = offset +
3201 					conn->sess->sess_ops->MaxBurstLength;
3202 
3203 				if (new_data_end > cmd->se_cmd.data_length)
3204 					xfer_len = cmd->se_cmd.data_length - offset;
3205 				else
3206 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3207 			}
3208 
3209 			if ((s32)xfer_len < 0) {
3210 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3211 				break;
3212 			}
3213 
3214 			cmd->r2t_offset += xfer_len;
3215 
3216 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3217 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3218 		} else {
3219 			struct iscsi_seq *seq;
3220 
3221 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3222 			if (!seq) {
3223 				spin_unlock_bh(&cmd->r2t_lock);
3224 				return -1;
3225 			}
3226 
3227 			offset = seq->offset;
3228 			xfer_len = seq->xfer_len;
3229 
3230 			if (cmd->seq_send_order == cmd->seq_count)
3231 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3232 		}
3233 		cmd->outstanding_r2ts++;
3234 		first_r2t = 0;
3235 
3236 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3237 			spin_unlock_bh(&cmd->r2t_lock);
3238 			return -1;
3239 		}
3240 
3241 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3242 			break;
3243 	}
3244 	spin_unlock_bh(&cmd->r2t_lock);
3245 
3246 	return 0;
3247 }
3248 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3249 
3250 void iscsit_build_rsp_pdu(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3251 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3252 {
3253 	if (inc_stat_sn)
3254 		cmd->stat_sn = conn->stat_sn++;
3255 
3256 	atomic_long_inc(&conn->sess->rsp_pdus);
3257 
3258 	memset(hdr, 0, ISCSI_HDR_LEN);
3259 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3260 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3261 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3262 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3263 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3264 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3265 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3266 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3267 	}
3268 	hdr->response		= cmd->iscsi_response;
3269 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3270 	hdr->itt		= cmd->init_task_tag;
3271 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3272 
3273 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3274 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3275 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3276 
3277 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3278 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3279 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3280 		cmd->se_cmd.scsi_status, conn->cid);
3281 }
3282 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3283 
3284 static int iscsit_send_response(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3285 {
3286 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3287 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3288 	void *data_buf = NULL;
3289 	u32 padding = 0, data_buf_len = 0;
3290 
3291 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3292 
3293 	/*
3294 	 * Attach SENSE DATA payload to iSCSI Response PDU
3295 	 */
3296 	if (cmd->se_cmd.sense_buffer &&
3297 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3298 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3299 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3300 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3301 
3302 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3303 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3304 		data_buf = cmd->sense_buffer;
3305 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3306 
3307 		if (padding) {
3308 			memset(cmd->sense_buffer +
3309 				cmd->se_cmd.scsi_sense_length, 0, padding);
3310 			pr_debug("Adding %u bytes of padding to"
3311 				" SENSE.\n", padding);
3312 		}
3313 
3314 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3315 				" Response PDU\n",
3316 				cmd->se_cmd.scsi_sense_length);
3317 	}
3318 
3319 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3320 						     data_buf_len);
3321 }
3322 
3323 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3324 {
3325 	switch (se_tmr->response) {
3326 	case TMR_FUNCTION_COMPLETE:
3327 		return ISCSI_TMF_RSP_COMPLETE;
3328 	case TMR_TASK_DOES_NOT_EXIST:
3329 		return ISCSI_TMF_RSP_NO_TASK;
3330 	case TMR_LUN_DOES_NOT_EXIST:
3331 		return ISCSI_TMF_RSP_NO_LUN;
3332 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3333 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3334 	case TMR_FUNCTION_REJECTED:
3335 	default:
3336 		return ISCSI_TMF_RSP_REJECTED;
3337 	}
3338 }
3339 
3340 void
3341 iscsit_build_task_mgt_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3342 			  struct iscsi_tm_rsp *hdr)
3343 {
3344 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3345 
3346 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3347 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3348 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3349 	hdr->itt		= cmd->init_task_tag;
3350 	cmd->stat_sn		= conn->stat_sn++;
3351 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3352 
3353 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3354 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3355 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3356 
3357 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3358 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3359 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3360 }
3361 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3362 
3363 static int
3364 iscsit_send_task_mgt_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3365 {
3366 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3367 
3368 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3369 
3370 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3371 }
3372 
3373 #define SENDTARGETS_BUF_LIMIT 32768U
3374 
3375 static int
3376 iscsit_build_sendtargets_response(struct iscsit_cmd *cmd,
3377 				  enum iscsit_transport_type network_transport,
3378 				  int skip_bytes, bool *completed)
3379 {
3380 	char *payload = NULL;
3381 	struct iscsit_conn *conn = cmd->conn;
3382 	struct iscsi_portal_group *tpg;
3383 	struct iscsi_tiqn *tiqn;
3384 	struct iscsi_tpg_np *tpg_np;
3385 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3386 	int target_name_printed;
3387 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3388 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3389 	bool active;
3390 
3391 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3392 			 SENDTARGETS_BUF_LIMIT);
3393 
3394 	payload = kzalloc(buffer_len, GFP_KERNEL);
3395 	if (!payload)
3396 		return -ENOMEM;
3397 
3398 	/*
3399 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3400 	 * explicit case..
3401 	 */
3402 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3403 		text_ptr = strchr(text_in, '=');
3404 		if (!text_ptr) {
3405 			pr_err("Unable to locate '=' string in text_in:"
3406 			       " %s\n", text_in);
3407 			kfree(payload);
3408 			return -EINVAL;
3409 		}
3410 		/*
3411 		 * Skip over '=' character..
3412 		 */
3413 		text_ptr += 1;
3414 	}
3415 
3416 	spin_lock(&tiqn_lock);
3417 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3418 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3419 		     strcmp(tiqn->tiqn, text_ptr)) {
3420 			continue;
3421 		}
3422 
3423 		target_name_printed = 0;
3424 
3425 		spin_lock(&tiqn->tiqn_tpg_lock);
3426 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3427 
3428 			/* If demo_mode_discovery=0 and generate_node_acls=0
3429 			 * (demo mode dislabed) do not return
3430 			 * TargetName+TargetAddress unless a NodeACL exists.
3431 			 */
3432 
3433 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3434 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3435 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3436 				cmd->conn->sess->sess_ops->InitiatorName))) {
3437 				continue;
3438 			}
3439 
3440 			spin_lock(&tpg->tpg_state_lock);
3441 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3442 			spin_unlock(&tpg->tpg_state_lock);
3443 
3444 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3445 				continue;
3446 
3447 			spin_lock(&tpg->tpg_np_lock);
3448 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3449 						tpg_np_list) {
3450 				struct iscsi_np *np = tpg_np->tpg_np;
3451 				struct sockaddr_storage *sockaddr;
3452 
3453 				if (np->np_network_transport != network_transport)
3454 					continue;
3455 
3456 				if (!target_name_printed) {
3457 					len = sprintf(buf, "TargetName=%s",
3458 						      tiqn->tiqn);
3459 					len += 1;
3460 
3461 					if ((len + payload_len) > buffer_len) {
3462 						spin_unlock(&tpg->tpg_np_lock);
3463 						spin_unlock(&tiqn->tiqn_tpg_lock);
3464 						end_of_buf = 1;
3465 						goto eob;
3466 					}
3467 
3468 					if (skip_bytes && len <= skip_bytes) {
3469 						skip_bytes -= len;
3470 					} else {
3471 						memcpy(payload + payload_len, buf, len);
3472 						payload_len += len;
3473 						target_name_printed = 1;
3474 						if (len > skip_bytes)
3475 							skip_bytes = 0;
3476 					}
3477 				}
3478 
3479 				if (inet_addr_is_any((struct sockaddr *)&np->np_sockaddr))
3480 					sockaddr = &conn->local_sockaddr;
3481 				else
3482 					sockaddr = &np->np_sockaddr;
3483 
3484 				len = sprintf(buf, "TargetAddress="
3485 					      "%pISpc,%hu",
3486 					      sockaddr,
3487 					      tpg->tpgt);
3488 				len += 1;
3489 
3490 				if ((len + payload_len) > buffer_len) {
3491 					spin_unlock(&tpg->tpg_np_lock);
3492 					spin_unlock(&tiqn->tiqn_tpg_lock);
3493 					end_of_buf = 1;
3494 					goto eob;
3495 				}
3496 
3497 				if (skip_bytes && len <= skip_bytes) {
3498 					skip_bytes -= len;
3499 				} else {
3500 					memcpy(payload + payload_len, buf, len);
3501 					payload_len += len;
3502 					if (len > skip_bytes)
3503 						skip_bytes = 0;
3504 				}
3505 			}
3506 			spin_unlock(&tpg->tpg_np_lock);
3507 		}
3508 		spin_unlock(&tiqn->tiqn_tpg_lock);
3509 eob:
3510 		if (end_of_buf) {
3511 			*completed = false;
3512 			break;
3513 		}
3514 
3515 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3516 			break;
3517 	}
3518 	spin_unlock(&tiqn_lock);
3519 
3520 	cmd->buf_ptr = payload;
3521 
3522 	return payload_len;
3523 }
3524 
3525 int
3526 iscsit_build_text_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3527 		      struct iscsi_text_rsp *hdr,
3528 		      enum iscsit_transport_type network_transport)
3529 {
3530 	int text_length, padding;
3531 	bool completed = true;
3532 
3533 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3534 							cmd->read_data_done,
3535 							&completed);
3536 	if (text_length < 0)
3537 		return text_length;
3538 
3539 	if (completed) {
3540 		hdr->flags = ISCSI_FLAG_CMD_FINAL;
3541 	} else {
3542 		hdr->flags = ISCSI_FLAG_TEXT_CONTINUE;
3543 		cmd->read_data_done += text_length;
3544 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3545 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3546 	}
3547 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3548 	padding = ((-text_length) & 3);
3549 	hton24(hdr->dlength, text_length);
3550 	hdr->itt = cmd->init_task_tag;
3551 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3552 	cmd->stat_sn = conn->stat_sn++;
3553 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3554 
3555 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3556 	/*
3557 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3558 	 * correctly increment MaxCmdSN for each response answering a
3559 	 * non immediate text request with a valid CmdSN.
3560 	 */
3561 	cmd->maxcmdsn_inc = 0;
3562 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3563 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3564 
3565 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3566 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3567 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3568 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3569 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3570 
3571 	return text_length + padding;
3572 }
3573 EXPORT_SYMBOL(iscsit_build_text_rsp);
3574 
3575 static int iscsit_send_text_rsp(
3576 	struct iscsit_cmd *cmd,
3577 	struct iscsit_conn *conn)
3578 {
3579 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3580 	int text_length;
3581 
3582 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3583 				conn->conn_transport->transport_type);
3584 	if (text_length < 0)
3585 		return text_length;
3586 
3587 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3588 						     cmd->buf_ptr,
3589 						     text_length);
3590 }
3591 
3592 void
3593 iscsit_build_reject(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3594 		    struct iscsi_reject *hdr)
3595 {
3596 	hdr->opcode		= ISCSI_OP_REJECT;
3597 	hdr->reason		= cmd->reject_reason;
3598 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3599 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3600 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3601 	cmd->stat_sn		= conn->stat_sn++;
3602 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3603 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3604 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3605 
3606 }
3607 EXPORT_SYMBOL(iscsit_build_reject);
3608 
3609 static int iscsit_send_reject(
3610 	struct iscsit_cmd *cmd,
3611 	struct iscsit_conn *conn)
3612 {
3613 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3614 
3615 	iscsit_build_reject(cmd, conn, hdr);
3616 
3617 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3618 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3619 
3620 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3621 						     cmd->buf_ptr,
3622 						     ISCSI_HDR_LEN);
3623 }
3624 
3625 void iscsit_thread_get_cpumask(struct iscsit_conn *conn)
3626 {
3627 	int ord, cpu;
3628 	cpumask_var_t conn_allowed_cpumask;
3629 
3630 	/*
3631 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3632 	 * within iscsit_start_kthreads()
3633 	 *
3634 	 * Here we use bitmap_id to determine which CPU that this
3635 	 * iSCSI connection's RX/TX threads will be scheduled to
3636 	 * execute upon.
3637 	 */
3638 	if (!zalloc_cpumask_var(&conn_allowed_cpumask, GFP_KERNEL)) {
3639 		ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3640 		for_each_online_cpu(cpu) {
3641 			if (ord-- == 0) {
3642 				cpumask_set_cpu(cpu, conn->conn_cpumask);
3643 				return;
3644 			}
3645 		}
3646 	} else {
3647 		cpumask_and(conn_allowed_cpumask, iscsit_global->allowed_cpumask,
3648 			cpu_online_mask);
3649 
3650 		cpumask_clear(conn->conn_cpumask);
3651 		ord = conn->bitmap_id % cpumask_weight(conn_allowed_cpumask);
3652 		for_each_cpu(cpu, conn_allowed_cpumask) {
3653 			if (ord-- == 0) {
3654 				cpumask_set_cpu(cpu, conn->conn_cpumask);
3655 				free_cpumask_var(conn_allowed_cpumask);
3656 				return;
3657 			}
3658 		}
3659 		free_cpumask_var(conn_allowed_cpumask);
3660 	}
3661 	/*
3662 	 * This should never be reached..
3663 	 */
3664 	dump_stack();
3665 	cpumask_setall(conn->conn_cpumask);
3666 }
3667 
3668 static void iscsit_thread_reschedule(struct iscsit_conn *conn)
3669 {
3670 	/*
3671 	 * If iscsit_global->allowed_cpumask modified, reschedule iSCSI
3672 	 * connection's RX/TX threads update conn->allowed_cpumask.
3673 	 */
3674 	if (!cpumask_equal(iscsit_global->allowed_cpumask,
3675 			   conn->allowed_cpumask)) {
3676 		iscsit_thread_get_cpumask(conn);
3677 		conn->conn_tx_reset_cpumask = 1;
3678 		conn->conn_rx_reset_cpumask = 1;
3679 		cpumask_copy(conn->allowed_cpumask,
3680 			     iscsit_global->allowed_cpumask);
3681 	}
3682 }
3683 
3684 void iscsit_thread_check_cpumask(
3685 	struct iscsit_conn *conn,
3686 	struct task_struct *p,
3687 	int mode)
3688 {
3689 	/*
3690 	 * The TX and RX threads maybe call iscsit_thread_check_cpumask()
3691 	 * at the same time. The RX thread might be faster and return from
3692 	 * iscsit_thread_reschedule() with conn_rx_reset_cpumask set to 0.
3693 	 * Then the TX thread sets it back to 1.
3694 	 * The next time the RX thread loops, it sees conn_rx_reset_cpumask
3695 	 * set to 1 and calls set_cpus_allowed_ptr() again and set it to 0.
3696 	 */
3697 	iscsit_thread_reschedule(conn);
3698 
3699 	/*
3700 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3701 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3702 	 */
3703 	if (mode == 1) {
3704 		if (!conn->conn_tx_reset_cpumask)
3705 			return;
3706 	} else {
3707 		if (!conn->conn_rx_reset_cpumask)
3708 			return;
3709 	}
3710 
3711 	/*
3712 	 * Update the CPU mask for this single kthread so that
3713 	 * both TX and RX kthreads are scheduled to run on the
3714 	 * same CPU.
3715 	 */
3716 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3717 	if (mode == 1)
3718 		conn->conn_tx_reset_cpumask = 0;
3719 	else
3720 		conn->conn_rx_reset_cpumask = 0;
3721 }
3722 EXPORT_SYMBOL(iscsit_thread_check_cpumask);
3723 
3724 int
3725 iscsit_immediate_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
3726 {
3727 	int ret;
3728 
3729 	switch (state) {
3730 	case ISTATE_SEND_R2T:
3731 		ret = iscsit_send_r2t(cmd, conn);
3732 		if (ret < 0)
3733 			goto err;
3734 		break;
3735 	case ISTATE_REMOVE:
3736 		spin_lock_bh(&conn->cmd_lock);
3737 		list_del_init(&cmd->i_conn_node);
3738 		spin_unlock_bh(&conn->cmd_lock);
3739 
3740 		iscsit_free_cmd(cmd, false);
3741 		break;
3742 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3743 		iscsit_mod_nopin_response_timer(conn);
3744 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3745 		if (ret < 0)
3746 			goto err;
3747 		break;
3748 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3749 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3750 		if (ret < 0)
3751 			goto err;
3752 		break;
3753 	default:
3754 		pr_err("Unknown Opcode: 0x%02x ITT:"
3755 		       " 0x%08x, i_state: %d on CID: %hu\n",
3756 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3757 		       conn->cid);
3758 		goto err;
3759 	}
3760 
3761 	return 0;
3762 
3763 err:
3764 	return -1;
3765 }
3766 EXPORT_SYMBOL(iscsit_immediate_queue);
3767 
3768 static int
3769 iscsit_handle_immediate_queue(struct iscsit_conn *conn)
3770 {
3771 	struct iscsit_transport *t = conn->conn_transport;
3772 	struct iscsi_queue_req *qr;
3773 	struct iscsit_cmd *cmd;
3774 	u8 state;
3775 	int ret;
3776 
3777 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3778 		atomic_set(&conn->check_immediate_queue, 0);
3779 		cmd = qr->cmd;
3780 		state = qr->state;
3781 		kmem_cache_free(lio_qr_cache, qr);
3782 
3783 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3784 		if (ret < 0)
3785 			return ret;
3786 	}
3787 
3788 	return 0;
3789 }
3790 
3791 int
3792 iscsit_response_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
3793 {
3794 	int ret;
3795 
3796 check_rsp_state:
3797 	switch (state) {
3798 	case ISTATE_SEND_DATAIN:
3799 		ret = iscsit_send_datain(cmd, conn);
3800 		if (ret < 0)
3801 			goto err;
3802 		else if (!ret)
3803 			/* more drs */
3804 			goto check_rsp_state;
3805 		else if (ret == 1) {
3806 			/* all done */
3807 			spin_lock_bh(&cmd->istate_lock);
3808 			cmd->i_state = ISTATE_SENT_STATUS;
3809 			spin_unlock_bh(&cmd->istate_lock);
3810 
3811 			if (atomic_read(&conn->check_immediate_queue))
3812 				return 1;
3813 
3814 			return 0;
3815 		} else if (ret == 2) {
3816 			/* Still must send status,
3817 			   SCF_TRANSPORT_TASK_SENSE was set */
3818 			spin_lock_bh(&cmd->istate_lock);
3819 			cmd->i_state = ISTATE_SEND_STATUS;
3820 			spin_unlock_bh(&cmd->istate_lock);
3821 			state = ISTATE_SEND_STATUS;
3822 			goto check_rsp_state;
3823 		}
3824 
3825 		break;
3826 	case ISTATE_SEND_STATUS:
3827 	case ISTATE_SEND_STATUS_RECOVERY:
3828 		ret = iscsit_send_response(cmd, conn);
3829 		break;
3830 	case ISTATE_SEND_LOGOUTRSP:
3831 		ret = iscsit_send_logout(cmd, conn);
3832 		break;
3833 	case ISTATE_SEND_ASYNCMSG:
3834 		ret = iscsit_send_conn_drop_async_message(
3835 			cmd, conn);
3836 		break;
3837 	case ISTATE_SEND_NOPIN:
3838 		ret = iscsit_send_nopin(cmd, conn);
3839 		break;
3840 	case ISTATE_SEND_REJECT:
3841 		ret = iscsit_send_reject(cmd, conn);
3842 		break;
3843 	case ISTATE_SEND_TASKMGTRSP:
3844 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3845 		if (ret != 0)
3846 			break;
3847 		ret = iscsit_tmr_post_handler(cmd, conn);
3848 		if (ret != 0)
3849 			iscsit_fall_back_to_erl0(conn->sess);
3850 		break;
3851 	case ISTATE_SEND_TEXTRSP:
3852 		ret = iscsit_send_text_rsp(cmd, conn);
3853 		break;
3854 	default:
3855 		pr_err("Unknown Opcode: 0x%02x ITT:"
3856 		       " 0x%08x, i_state: %d on CID: %hu\n",
3857 		       cmd->iscsi_opcode, cmd->init_task_tag,
3858 		       state, conn->cid);
3859 		goto err;
3860 	}
3861 	if (ret < 0)
3862 		goto err;
3863 
3864 	switch (state) {
3865 	case ISTATE_SEND_LOGOUTRSP:
3866 		if (!iscsit_logout_post_handler(cmd, conn))
3867 			return -ECONNRESET;
3868 		fallthrough;
3869 	case ISTATE_SEND_STATUS:
3870 	case ISTATE_SEND_ASYNCMSG:
3871 	case ISTATE_SEND_NOPIN:
3872 	case ISTATE_SEND_STATUS_RECOVERY:
3873 	case ISTATE_SEND_TEXTRSP:
3874 	case ISTATE_SEND_TASKMGTRSP:
3875 	case ISTATE_SEND_REJECT:
3876 		spin_lock_bh(&cmd->istate_lock);
3877 		cmd->i_state = ISTATE_SENT_STATUS;
3878 		spin_unlock_bh(&cmd->istate_lock);
3879 		break;
3880 	default:
3881 		pr_err("Unknown Opcode: 0x%02x ITT:"
3882 		       " 0x%08x, i_state: %d on CID: %hu\n",
3883 		       cmd->iscsi_opcode, cmd->init_task_tag,
3884 		       cmd->i_state, conn->cid);
3885 		goto err;
3886 	}
3887 
3888 	if (atomic_read(&conn->check_immediate_queue))
3889 		return 1;
3890 
3891 	return 0;
3892 
3893 err:
3894 	return -1;
3895 }
3896 EXPORT_SYMBOL(iscsit_response_queue);
3897 
3898 static int iscsit_handle_response_queue(struct iscsit_conn *conn)
3899 {
3900 	struct iscsit_transport *t = conn->conn_transport;
3901 	struct iscsi_queue_req *qr;
3902 	struct iscsit_cmd *cmd;
3903 	u8 state;
3904 	int ret;
3905 
3906 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3907 		cmd = qr->cmd;
3908 		state = qr->state;
3909 		kmem_cache_free(lio_qr_cache, qr);
3910 
3911 		ret = t->iscsit_response_queue(conn, cmd, state);
3912 		if (ret == 1 || ret < 0)
3913 			return ret;
3914 	}
3915 
3916 	return 0;
3917 }
3918 
3919 int iscsi_target_tx_thread(void *arg)
3920 {
3921 	int ret = 0;
3922 	struct iscsit_conn *conn = arg;
3923 	bool conn_freed = false;
3924 
3925 	/*
3926 	 * Allow ourselves to be interrupted by SIGINT so that a
3927 	 * connection recovery / failure event can be triggered externally.
3928 	 */
3929 	allow_signal(SIGINT);
3930 
3931 	while (!kthread_should_stop()) {
3932 		/*
3933 		 * Ensure that both TX and RX per connection kthreads
3934 		 * are scheduled to run on the same CPU.
3935 		 */
3936 		iscsit_thread_check_cpumask(conn, current, 1);
3937 
3938 		wait_event_interruptible(conn->queues_wq,
3939 					 !iscsit_conn_all_queues_empty(conn));
3940 
3941 		if (signal_pending(current))
3942 			goto transport_err;
3943 
3944 get_immediate:
3945 		ret = iscsit_handle_immediate_queue(conn);
3946 		if (ret < 0)
3947 			goto transport_err;
3948 
3949 		ret = iscsit_handle_response_queue(conn);
3950 		if (ret == 1) {
3951 			goto get_immediate;
3952 		} else if (ret == -ECONNRESET) {
3953 			conn_freed = true;
3954 			goto out;
3955 		} else if (ret < 0) {
3956 			goto transport_err;
3957 		}
3958 	}
3959 
3960 transport_err:
3961 	/*
3962 	 * Avoid the normal connection failure code-path if this connection
3963 	 * is still within LOGIN mode, and iscsi_np process context is
3964 	 * responsible for cleaning up the early connection failure.
3965 	 */
3966 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3967 		iscsit_take_action_for_connection_exit(conn, &conn_freed);
3968 out:
3969 	if (!conn_freed) {
3970 		while (!kthread_should_stop()) {
3971 			msleep(100);
3972 		}
3973 	}
3974 	return 0;
3975 }
3976 
3977 static int iscsi_target_rx_opcode(struct iscsit_conn *conn, unsigned char *buf)
3978 {
3979 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3980 	struct iscsit_cmd *cmd;
3981 	int ret = 0;
3982 
3983 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3984 	case ISCSI_OP_SCSI_CMD:
3985 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3986 		if (!cmd)
3987 			goto reject;
3988 
3989 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3990 		break;
3991 	case ISCSI_OP_SCSI_DATA_OUT:
3992 		ret = iscsit_handle_data_out(conn, buf);
3993 		break;
3994 	case ISCSI_OP_NOOP_OUT:
3995 		cmd = NULL;
3996 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3997 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3998 			if (!cmd)
3999 				goto reject;
4000 		}
4001 		ret = iscsit_handle_nop_out(conn, cmd, buf);
4002 		break;
4003 	case ISCSI_OP_SCSI_TMFUNC:
4004 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4005 		if (!cmd)
4006 			goto reject;
4007 
4008 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
4009 		break;
4010 	case ISCSI_OP_TEXT:
4011 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
4012 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
4013 			if (!cmd)
4014 				goto reject;
4015 		} else {
4016 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4017 			if (!cmd)
4018 				goto reject;
4019 		}
4020 
4021 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
4022 		break;
4023 	case ISCSI_OP_LOGOUT:
4024 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
4025 		if (!cmd)
4026 			goto reject;
4027 
4028 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
4029 		if (ret > 0)
4030 			wait_for_completion_timeout(&conn->conn_logout_comp,
4031 					SECONDS_FOR_LOGOUT_COMP * HZ);
4032 		break;
4033 	case ISCSI_OP_SNACK:
4034 		ret = iscsit_handle_snack(conn, buf);
4035 		break;
4036 	default:
4037 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
4038 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
4039 			pr_err("Cannot recover from unknown"
4040 			" opcode while ERL=0, closing iSCSI connection.\n");
4041 			return -1;
4042 		}
4043 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
4044 		       " closing iSCSI connection.\n");
4045 		ret = -1;
4046 		break;
4047 	}
4048 
4049 	return ret;
4050 reject:
4051 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4052 }
4053 
4054 static bool iscsi_target_check_conn_state(struct iscsit_conn *conn)
4055 {
4056 	bool ret;
4057 
4058 	spin_lock_bh(&conn->state_lock);
4059 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
4060 	spin_unlock_bh(&conn->state_lock);
4061 
4062 	return ret;
4063 }
4064 
4065 static void iscsit_get_rx_pdu(struct iscsit_conn *conn)
4066 {
4067 	int ret;
4068 	u8 *buffer, *tmp_buf, opcode;
4069 	u32 checksum = 0, digest = 0;
4070 	struct iscsi_hdr *hdr;
4071 	struct kvec iov;
4072 
4073 	buffer = kcalloc(ISCSI_HDR_LEN, sizeof(*buffer), GFP_KERNEL);
4074 	if (!buffer)
4075 		return;
4076 
4077 	while (!kthread_should_stop()) {
4078 		/*
4079 		 * Ensure that both TX and RX per connection kthreads
4080 		 * are scheduled to run on the same CPU.
4081 		 */
4082 		iscsit_thread_check_cpumask(conn, current, 0);
4083 
4084 		memset(&iov, 0, sizeof(struct kvec));
4085 
4086 		iov.iov_base	= buffer;
4087 		iov.iov_len	= ISCSI_HDR_LEN;
4088 
4089 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4090 		if (ret != ISCSI_HDR_LEN) {
4091 			iscsit_rx_thread_wait_for_tcp(conn);
4092 			break;
4093 		}
4094 
4095 		hdr = (struct iscsi_hdr *) buffer;
4096 		if (hdr->hlength) {
4097 			iov.iov_len = hdr->hlength * 4;
4098 			tmp_buf = krealloc(buffer,
4099 					  ISCSI_HDR_LEN + iov.iov_len,
4100 					  GFP_KERNEL);
4101 			if (!tmp_buf)
4102 				break;
4103 
4104 			buffer = tmp_buf;
4105 			iov.iov_base = &buffer[ISCSI_HDR_LEN];
4106 
4107 			ret = rx_data(conn, &iov, 1, iov.iov_len);
4108 			if (ret != iov.iov_len) {
4109 				iscsit_rx_thread_wait_for_tcp(conn);
4110 				break;
4111 			}
4112 		}
4113 
4114 		if (conn->conn_ops->HeaderDigest) {
4115 			iov.iov_base	= &digest;
4116 			iov.iov_len	= ISCSI_CRC_LEN;
4117 
4118 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4119 			if (ret != ISCSI_CRC_LEN) {
4120 				iscsit_rx_thread_wait_for_tcp(conn);
4121 				break;
4122 			}
4123 
4124 			iscsit_do_crypto_hash_buf(conn->conn_rx_hash, buffer,
4125 						  ISCSI_HDR_LEN, 0, NULL,
4126 						  &checksum);
4127 
4128 			if (digest != checksum) {
4129 				pr_err("HeaderDigest CRC32C failed,"
4130 					" received 0x%08x, computed 0x%08x\n",
4131 					digest, checksum);
4132 				/*
4133 				 * Set the PDU to 0xff so it will intentionally
4134 				 * hit default in the switch below.
4135 				 */
4136 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4137 				atomic_long_inc(&conn->sess->conn_digest_errors);
4138 			} else {
4139 				pr_debug("Got HeaderDigest CRC32C"
4140 						" 0x%08x\n", checksum);
4141 			}
4142 		}
4143 
4144 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4145 			break;
4146 
4147 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4148 
4149 		if (conn->sess->sess_ops->SessionType &&
4150 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4151 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4152 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4153 			" while in Discovery Session, rejecting.\n", opcode);
4154 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4155 					  buffer);
4156 			break;
4157 		}
4158 
4159 		ret = iscsi_target_rx_opcode(conn, buffer);
4160 		if (ret < 0)
4161 			break;
4162 	}
4163 
4164 	kfree(buffer);
4165 }
4166 
4167 int iscsi_target_rx_thread(void *arg)
4168 {
4169 	int rc;
4170 	struct iscsit_conn *conn = arg;
4171 	bool conn_freed = false;
4172 
4173 	/*
4174 	 * Allow ourselves to be interrupted by SIGINT so that a
4175 	 * connection recovery / failure event can be triggered externally.
4176 	 */
4177 	allow_signal(SIGINT);
4178 	/*
4179 	 * Wait for iscsi_post_login_handler() to complete before allowing
4180 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4181 	 */
4182 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4183 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4184 		goto out;
4185 
4186 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4187 		return 0;
4188 
4189 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4190 
4191 	if (!signal_pending(current))
4192 		atomic_set(&conn->transport_failed, 1);
4193 	iscsit_take_action_for_connection_exit(conn, &conn_freed);
4194 
4195 out:
4196 	if (!conn_freed) {
4197 		while (!kthread_should_stop()) {
4198 			msleep(100);
4199 		}
4200 	}
4201 
4202 	return 0;
4203 }
4204 
4205 static void iscsit_release_commands_from_conn(struct iscsit_conn *conn)
4206 {
4207 	LIST_HEAD(tmp_list);
4208 	struct iscsit_cmd *cmd = NULL, *cmd_tmp = NULL;
4209 	struct iscsit_session *sess = conn->sess;
4210 	/*
4211 	 * We expect this function to only ever be called from either RX or TX
4212 	 * thread context via iscsit_close_connection() once the other context
4213 	 * has been reset -> returned sleeping pre-handler state.
4214 	 */
4215 	spin_lock_bh(&conn->cmd_lock);
4216 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4217 
4218 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4219 		struct se_cmd *se_cmd = &cmd->se_cmd;
4220 
4221 		if (se_cmd->se_tfo != NULL) {
4222 			spin_lock_irq(&se_cmd->t_state_lock);
4223 			if (se_cmd->transport_state & CMD_T_ABORTED) {
4224 				/*
4225 				 * LIO's abort path owns the cleanup for this,
4226 				 * so put it back on the list and let
4227 				 * aborted_task handle it.
4228 				 */
4229 				list_move_tail(&cmd->i_conn_node,
4230 					       &conn->conn_cmd_list);
4231 			} else {
4232 				se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4233 			}
4234 			spin_unlock_irq(&se_cmd->t_state_lock);
4235 		}
4236 	}
4237 	spin_unlock_bh(&conn->cmd_lock);
4238 
4239 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4240 		list_del_init(&cmd->i_conn_node);
4241 
4242 		iscsit_increment_maxcmdsn(cmd, sess);
4243 		iscsit_free_cmd(cmd, true);
4244 
4245 	}
4246 }
4247 
4248 static void iscsit_stop_timers_for_cmds(
4249 	struct iscsit_conn *conn)
4250 {
4251 	struct iscsit_cmd *cmd;
4252 
4253 	spin_lock_bh(&conn->cmd_lock);
4254 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4255 		if (cmd->data_direction == DMA_TO_DEVICE)
4256 			iscsit_stop_dataout_timer(cmd);
4257 	}
4258 	spin_unlock_bh(&conn->cmd_lock);
4259 }
4260 
4261 int iscsit_close_connection(
4262 	struct iscsit_conn *conn)
4263 {
4264 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4265 	struct iscsit_session	*sess = conn->sess;
4266 
4267 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4268 		" %u\n", conn->cid, sess->sid);
4269 	/*
4270 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4271 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4272 	 * sleeping and the logout response never got sent because the
4273 	 * connection failed.
4274 	 *
4275 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4276 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4277 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4278 	 * and to avoid iscsit_conn pointer dereference in iser-target code.
4279 	 */
4280 	if (!conn->conn_transport->rdma_shutdown)
4281 		complete(&conn->conn_logout_comp);
4282 
4283 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4284 		if (conn->tx_thread &&
4285 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4286 			send_sig(SIGINT, conn->tx_thread, 1);
4287 			kthread_stop(conn->tx_thread);
4288 		}
4289 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4290 		if (conn->rx_thread &&
4291 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4292 			send_sig(SIGINT, conn->rx_thread, 1);
4293 			kthread_stop(conn->rx_thread);
4294 		}
4295 	}
4296 
4297 	spin_lock(&iscsit_global->ts_bitmap_lock);
4298 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4299 			      get_order(1));
4300 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4301 
4302 	iscsit_stop_timers_for_cmds(conn);
4303 	iscsit_stop_nopin_response_timer(conn);
4304 	iscsit_stop_nopin_timer(conn);
4305 
4306 	if (conn->conn_transport->iscsit_wait_conn)
4307 		conn->conn_transport->iscsit_wait_conn(conn);
4308 
4309 	/*
4310 	 * During Connection recovery drop unacknowledged out of order
4311 	 * commands for this connection, and prepare the other commands
4312 	 * for reallegiance.
4313 	 *
4314 	 * During normal operation clear the out of order commands (but
4315 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4316 	 * struct iscsit_cmds.
4317 	 */
4318 	if (atomic_read(&conn->connection_recovery)) {
4319 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4320 		iscsit_prepare_cmds_for_reallegiance(conn);
4321 	} else {
4322 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4323 		iscsit_release_commands_from_conn(conn);
4324 	}
4325 	iscsit_free_queue_reqs_for_conn(conn);
4326 
4327 	/*
4328 	 * Handle decrementing session or connection usage count if
4329 	 * a logout response was not able to be sent because the
4330 	 * connection failed.  Fall back to Session Recovery here.
4331 	 */
4332 	if (atomic_read(&conn->conn_logout_remove)) {
4333 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4334 			iscsit_dec_conn_usage_count(conn);
4335 			iscsit_dec_session_usage_count(sess);
4336 		}
4337 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4338 			iscsit_dec_conn_usage_count(conn);
4339 
4340 		atomic_set(&conn->conn_logout_remove, 0);
4341 		atomic_set(&sess->session_reinstatement, 0);
4342 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4343 	}
4344 
4345 	spin_lock_bh(&sess->conn_lock);
4346 	list_del(&conn->conn_list);
4347 
4348 	/*
4349 	 * Attempt to let the Initiator know this connection failed by
4350 	 * sending an Connection Dropped Async Message on another
4351 	 * active connection.
4352 	 */
4353 	if (atomic_read(&conn->connection_recovery))
4354 		iscsit_build_conn_drop_async_message(conn);
4355 
4356 	spin_unlock_bh(&sess->conn_lock);
4357 
4358 	/*
4359 	 * If connection reinstatement is being performed on this connection,
4360 	 * up the connection reinstatement semaphore that is being blocked on
4361 	 * in iscsit_cause_connection_reinstatement().
4362 	 */
4363 	spin_lock_bh(&conn->state_lock);
4364 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4365 		spin_unlock_bh(&conn->state_lock);
4366 		complete(&conn->conn_wait_comp);
4367 		wait_for_completion(&conn->conn_post_wait_comp);
4368 		spin_lock_bh(&conn->state_lock);
4369 	}
4370 
4371 	/*
4372 	 * If connection reinstatement is being performed on this connection
4373 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4374 	 * connection wait rcfr semaphore that is being blocked on
4375 	 * an iscsit_connection_reinstatement_rcfr().
4376 	 */
4377 	if (atomic_read(&conn->connection_wait_rcfr)) {
4378 		spin_unlock_bh(&conn->state_lock);
4379 		complete(&conn->conn_wait_rcfr_comp);
4380 		wait_for_completion(&conn->conn_post_wait_comp);
4381 		spin_lock_bh(&conn->state_lock);
4382 	}
4383 	atomic_set(&conn->connection_reinstatement, 1);
4384 	spin_unlock_bh(&conn->state_lock);
4385 
4386 	/*
4387 	 * If any other processes are accessing this connection pointer we
4388 	 * must wait until they have completed.
4389 	 */
4390 	iscsit_check_conn_usage_count(conn);
4391 
4392 	ahash_request_free(conn->conn_tx_hash);
4393 	if (conn->conn_rx_hash) {
4394 		struct crypto_ahash *tfm;
4395 
4396 		tfm = crypto_ahash_reqtfm(conn->conn_rx_hash);
4397 		ahash_request_free(conn->conn_rx_hash);
4398 		crypto_free_ahash(tfm);
4399 	}
4400 
4401 	if (conn->sock)
4402 		sock_release(conn->sock);
4403 
4404 	if (conn->conn_transport->iscsit_free_conn)
4405 		conn->conn_transport->iscsit_free_conn(conn);
4406 
4407 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4408 	conn->conn_state = TARG_CONN_STATE_FREE;
4409 	iscsit_free_conn(conn);
4410 
4411 	spin_lock_bh(&sess->conn_lock);
4412 	atomic_dec(&sess->nconn);
4413 	pr_debug("Decremented iSCSI connection count to %d from node:"
4414 		" %s\n", atomic_read(&sess->nconn),
4415 		sess->sess_ops->InitiatorName);
4416 	/*
4417 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4418 	 * Session that they all fail.
4419 	 */
4420 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4421 	     !atomic_read(&sess->session_logout))
4422 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4423 
4424 	/*
4425 	 * If this was not the last connection in the session, and we are
4426 	 * performing session reinstatement or falling back to ERL=0, call
4427 	 * iscsit_stop_session() without sleeping to shutdown the other
4428 	 * active connections.
4429 	 */
4430 	if (atomic_read(&sess->nconn)) {
4431 		if (!atomic_read(&sess->session_reinstatement) &&
4432 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4433 			spin_unlock_bh(&sess->conn_lock);
4434 			return 0;
4435 		}
4436 		if (!atomic_read(&sess->session_stop_active)) {
4437 			atomic_set(&sess->session_stop_active, 1);
4438 			spin_unlock_bh(&sess->conn_lock);
4439 			iscsit_stop_session(sess, 0, 0);
4440 			return 0;
4441 		}
4442 		spin_unlock_bh(&sess->conn_lock);
4443 		return 0;
4444 	}
4445 
4446 	/*
4447 	 * If this was the last connection in the session and one of the
4448 	 * following is occurring:
4449 	 *
4450 	 * Session Reinstatement is not being performed, and are falling back
4451 	 * to ERL=0 call iscsit_close_session().
4452 	 *
4453 	 * Session Logout was requested.  iscsit_close_session() will be called
4454 	 * elsewhere.
4455 	 *
4456 	 * Session Continuation is not being performed, start the Time2Retain
4457 	 * handler and check if sleep_on_sess_wait_sem is active.
4458 	 */
4459 	if (!atomic_read(&sess->session_reinstatement) &&
4460 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4461 		spin_unlock_bh(&sess->conn_lock);
4462 		complete_all(&sess->session_wait_comp);
4463 		iscsit_close_session(sess, true);
4464 
4465 		return 0;
4466 	} else if (atomic_read(&sess->session_logout)) {
4467 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4468 		sess->session_state = TARG_SESS_STATE_FREE;
4469 
4470 		if (atomic_read(&sess->session_close)) {
4471 			spin_unlock_bh(&sess->conn_lock);
4472 			complete_all(&sess->session_wait_comp);
4473 			iscsit_close_session(sess, true);
4474 		} else {
4475 			spin_unlock_bh(&sess->conn_lock);
4476 		}
4477 
4478 		return 0;
4479 	} else {
4480 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4481 		sess->session_state = TARG_SESS_STATE_FAILED;
4482 
4483 		if (!atomic_read(&sess->session_continuation))
4484 			iscsit_start_time2retain_handler(sess);
4485 
4486 		if (atomic_read(&sess->session_close)) {
4487 			spin_unlock_bh(&sess->conn_lock);
4488 			complete_all(&sess->session_wait_comp);
4489 			iscsit_close_session(sess, true);
4490 		} else {
4491 			spin_unlock_bh(&sess->conn_lock);
4492 		}
4493 
4494 		return 0;
4495 	}
4496 }
4497 
4498 /*
4499  * If the iSCSI Session for the iSCSI Initiator Node exists,
4500  * forcefully shutdown the iSCSI NEXUS.
4501  */
4502 int iscsit_close_session(struct iscsit_session *sess, bool can_sleep)
4503 {
4504 	struct iscsi_portal_group *tpg = sess->tpg;
4505 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4506 
4507 	if (atomic_read(&sess->nconn)) {
4508 		pr_err("%d connection(s) still exist for iSCSI session"
4509 			" to %s\n", atomic_read(&sess->nconn),
4510 			sess->sess_ops->InitiatorName);
4511 		BUG();
4512 	}
4513 
4514 	spin_lock_bh(&se_tpg->session_lock);
4515 	atomic_set(&sess->session_logout, 1);
4516 	atomic_set(&sess->session_reinstatement, 1);
4517 	iscsit_stop_time2retain_timer(sess);
4518 	spin_unlock_bh(&se_tpg->session_lock);
4519 
4520 	/*
4521 	 * transport_deregister_session_configfs() will clear the
4522 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4523 	 * can be setting it again with __transport_register_session() in
4524 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4525 	 * completes in iscsi_np context.
4526 	 */
4527 	transport_deregister_session_configfs(sess->se_sess);
4528 
4529 	/*
4530 	 * If any other processes are accessing this session pointer we must
4531 	 * wait until they have completed.  If we are in an interrupt (the
4532 	 * time2retain handler) and contain and active session usage count we
4533 	 * restart the timer and exit.
4534 	 */
4535 	if (iscsit_check_session_usage_count(sess, can_sleep)) {
4536 		atomic_set(&sess->session_logout, 0);
4537 		iscsit_start_time2retain_handler(sess);
4538 		return 0;
4539 	}
4540 
4541 	transport_deregister_session(sess->se_sess);
4542 
4543 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4544 		iscsit_free_connection_recovery_entries(sess);
4545 
4546 	iscsit_free_all_ooo_cmdsns(sess);
4547 
4548 	spin_lock_bh(&se_tpg->session_lock);
4549 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4550 	sess->session_state = TARG_SESS_STATE_FREE;
4551 	pr_debug("Released iSCSI session from node: %s\n",
4552 			sess->sess_ops->InitiatorName);
4553 	tpg->nsessions--;
4554 	if (tpg->tpg_tiqn)
4555 		tpg->tpg_tiqn->tiqn_nsessions--;
4556 
4557 	pr_debug("Decremented number of active iSCSI Sessions on"
4558 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4559 
4560 	ida_free(&sess_ida, sess->session_index);
4561 	kfree(sess->sess_ops);
4562 	sess->sess_ops = NULL;
4563 	spin_unlock_bh(&se_tpg->session_lock);
4564 
4565 	kfree(sess);
4566 	return 0;
4567 }
4568 
4569 static void iscsit_logout_post_handler_closesession(
4570 	struct iscsit_conn *conn)
4571 {
4572 	struct iscsit_session *sess = conn->sess;
4573 	int sleep = 1;
4574 	/*
4575 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4576 	 * context during session logout, so clear tx_thread_active and
4577 	 * sleep if iscsit_close_connection() has not already occured.
4578 	 *
4579 	 * Since iser-target invokes this logic from it's own workqueue,
4580 	 * always sleep waiting for RX/TX thread shutdown to complete
4581 	 * within iscsit_close_connection().
4582 	 */
4583 	if (!conn->conn_transport->rdma_shutdown) {
4584 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4585 		if (!sleep)
4586 			return;
4587 	}
4588 
4589 	atomic_set(&conn->conn_logout_remove, 0);
4590 	complete(&conn->conn_logout_comp);
4591 
4592 	iscsit_dec_conn_usage_count(conn);
4593 	atomic_set(&sess->session_close, 1);
4594 	iscsit_stop_session(sess, sleep, sleep);
4595 	iscsit_dec_session_usage_count(sess);
4596 }
4597 
4598 static void iscsit_logout_post_handler_samecid(
4599 	struct iscsit_conn *conn)
4600 {
4601 	int sleep = 1;
4602 
4603 	if (!conn->conn_transport->rdma_shutdown) {
4604 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4605 		if (!sleep)
4606 			return;
4607 	}
4608 
4609 	atomic_set(&conn->conn_logout_remove, 0);
4610 	complete(&conn->conn_logout_comp);
4611 
4612 	iscsit_cause_connection_reinstatement(conn, sleep);
4613 	iscsit_dec_conn_usage_count(conn);
4614 }
4615 
4616 static void iscsit_logout_post_handler_diffcid(
4617 	struct iscsit_conn *conn,
4618 	u16 cid)
4619 {
4620 	struct iscsit_conn *l_conn;
4621 	struct iscsit_session *sess = conn->sess;
4622 	bool conn_found = false;
4623 
4624 	if (!sess)
4625 		return;
4626 
4627 	spin_lock_bh(&sess->conn_lock);
4628 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4629 		if (l_conn->cid == cid) {
4630 			iscsit_inc_conn_usage_count(l_conn);
4631 			conn_found = true;
4632 			break;
4633 		}
4634 	}
4635 	spin_unlock_bh(&sess->conn_lock);
4636 
4637 	if (!conn_found)
4638 		return;
4639 
4640 	if (l_conn->sock)
4641 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4642 
4643 	spin_lock_bh(&l_conn->state_lock);
4644 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4645 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4646 	spin_unlock_bh(&l_conn->state_lock);
4647 
4648 	iscsit_cause_connection_reinstatement(l_conn, 1);
4649 	iscsit_dec_conn_usage_count(l_conn);
4650 }
4651 
4652 /*
4653  *	Return of 0 causes the TX thread to restart.
4654  */
4655 int iscsit_logout_post_handler(
4656 	struct iscsit_cmd *cmd,
4657 	struct iscsit_conn *conn)
4658 {
4659 	int ret = 0;
4660 
4661 	switch (cmd->logout_reason) {
4662 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4663 		switch (cmd->logout_response) {
4664 		case ISCSI_LOGOUT_SUCCESS:
4665 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4666 		default:
4667 			iscsit_logout_post_handler_closesession(conn);
4668 			break;
4669 		}
4670 		break;
4671 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4672 		if (conn->cid == cmd->logout_cid) {
4673 			switch (cmd->logout_response) {
4674 			case ISCSI_LOGOUT_SUCCESS:
4675 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4676 			default:
4677 				iscsit_logout_post_handler_samecid(conn);
4678 				break;
4679 			}
4680 		} else {
4681 			switch (cmd->logout_response) {
4682 			case ISCSI_LOGOUT_SUCCESS:
4683 				iscsit_logout_post_handler_diffcid(conn,
4684 					cmd->logout_cid);
4685 				break;
4686 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4687 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4688 			default:
4689 				break;
4690 			}
4691 			ret = 1;
4692 		}
4693 		break;
4694 	case ISCSI_LOGOUT_REASON_RECOVERY:
4695 		switch (cmd->logout_response) {
4696 		case ISCSI_LOGOUT_SUCCESS:
4697 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4698 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4699 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4700 		default:
4701 			break;
4702 		}
4703 		ret = 1;
4704 		break;
4705 	default:
4706 		break;
4707 
4708 	}
4709 	return ret;
4710 }
4711 EXPORT_SYMBOL(iscsit_logout_post_handler);
4712 
4713 void iscsit_fail_session(struct iscsit_session *sess)
4714 {
4715 	struct iscsit_conn *conn;
4716 
4717 	spin_lock_bh(&sess->conn_lock);
4718 	list_for_each_entry(conn, &sess->sess_conn_list, conn_list) {
4719 		pr_debug("Moving to TARG_CONN_STATE_CLEANUP_WAIT.\n");
4720 		conn->conn_state = TARG_CONN_STATE_CLEANUP_WAIT;
4721 	}
4722 	spin_unlock_bh(&sess->conn_lock);
4723 
4724 	pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4725 	sess->session_state = TARG_SESS_STATE_FAILED;
4726 }
4727 
4728 void iscsit_stop_session(
4729 	struct iscsit_session *sess,
4730 	int session_sleep,
4731 	int connection_sleep)
4732 {
4733 	u16 conn_count = atomic_read(&sess->nconn);
4734 	struct iscsit_conn *conn, *conn_tmp = NULL;
4735 	int is_last;
4736 
4737 	spin_lock_bh(&sess->conn_lock);
4738 
4739 	if (connection_sleep) {
4740 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4741 				conn_list) {
4742 			if (conn_count == 0)
4743 				break;
4744 
4745 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4746 				is_last = 1;
4747 			} else {
4748 				iscsit_inc_conn_usage_count(conn_tmp);
4749 				is_last = 0;
4750 			}
4751 			iscsit_inc_conn_usage_count(conn);
4752 
4753 			spin_unlock_bh(&sess->conn_lock);
4754 			iscsit_cause_connection_reinstatement(conn, 1);
4755 			spin_lock_bh(&sess->conn_lock);
4756 
4757 			iscsit_dec_conn_usage_count(conn);
4758 			if (is_last == 0)
4759 				iscsit_dec_conn_usage_count(conn_tmp);
4760 			conn_count--;
4761 		}
4762 	} else {
4763 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4764 			iscsit_cause_connection_reinstatement(conn, 0);
4765 	}
4766 
4767 	if (session_sleep && atomic_read(&sess->nconn)) {
4768 		spin_unlock_bh(&sess->conn_lock);
4769 		wait_for_completion(&sess->session_wait_comp);
4770 	} else
4771 		spin_unlock_bh(&sess->conn_lock);
4772 }
4773 
4774 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4775 {
4776 	struct iscsit_session *sess;
4777 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4778 	struct se_session *se_sess, *se_sess_tmp;
4779 	LIST_HEAD(free_list);
4780 	int session_count = 0;
4781 
4782 	spin_lock_bh(&se_tpg->session_lock);
4783 	if (tpg->nsessions && !force) {
4784 		spin_unlock_bh(&se_tpg->session_lock);
4785 		return -1;
4786 	}
4787 
4788 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4789 			sess_list) {
4790 		sess = (struct iscsit_session *)se_sess->fabric_sess_ptr;
4791 
4792 		spin_lock(&sess->conn_lock);
4793 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4794 		    atomic_read(&sess->session_logout) ||
4795 		    atomic_read(&sess->session_close) ||
4796 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4797 			spin_unlock(&sess->conn_lock);
4798 			continue;
4799 		}
4800 		iscsit_inc_session_usage_count(sess);
4801 		atomic_set(&sess->session_reinstatement, 1);
4802 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4803 		atomic_set(&sess->session_close, 1);
4804 		spin_unlock(&sess->conn_lock);
4805 
4806 		list_move_tail(&se_sess->sess_list, &free_list);
4807 	}
4808 	spin_unlock_bh(&se_tpg->session_lock);
4809 
4810 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4811 		sess = (struct iscsit_session *)se_sess->fabric_sess_ptr;
4812 
4813 		list_del_init(&se_sess->sess_list);
4814 		iscsit_stop_session(sess, 1, 1);
4815 		iscsit_dec_session_usage_count(sess);
4816 		session_count++;
4817 	}
4818 
4819 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4820 			" Group: %hu\n", session_count, tpg->tpgt);
4821 	return 0;
4822 }
4823 
4824 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4825 MODULE_VERSION("4.1.x");
4826 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4827 MODULE_LICENSE("GPL");
4828 
4829 module_init(iscsi_target_init_module);
4830 module_exit(iscsi_target_cleanup_module);
4831