xref: /linux/drivers/target/iscsi/iscsi_target.c (revision b734412619821f3ed63ba63533f539672cb7a76d)
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 <linux/crc32c.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 <linux/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/target_core_backend.h>
30 #include <target/iscsi/iscsi_target_core.h>
31 #include "iscsi_target_parameters.h"
32 #include "iscsi_target_seq_pdu_list.h"
33 #include "iscsi_target_datain_values.h"
34 #include "iscsi_target_erl0.h"
35 #include "iscsi_target_erl1.h"
36 #include "iscsi_target_erl2.h"
37 #include "iscsi_target_login.h"
38 #include "iscsi_target_tmr.h"
39 #include "iscsi_target_tpg.h"
40 #include "iscsi_target_util.h"
41 #include "iscsi_target.h"
42 #include "iscsi_target_device.h"
43 #include <target/iscsi/iscsi_target_stat.h>
44 
45 #include <target/iscsi/iscsi_transport.h>
46 
47 static LIST_HEAD(g_tiqn_list);
48 static LIST_HEAD(g_np_list);
49 static DEFINE_SPINLOCK(tiqn_lock);
50 static DEFINE_MUTEX(np_lock);
51 
52 static struct idr tiqn_idr;
53 DEFINE_IDA(sess_ida);
54 struct mutex auth_id_lock;
55 
56 struct iscsit_global *iscsit_global;
57 
58 struct kmem_cache *lio_qr_cache;
59 struct kmem_cache *lio_dr_cache;
60 struct kmem_cache *lio_ooo_cache;
61 struct kmem_cache *lio_r2t_cache;
62 
63 static int iscsit_handle_immediate_data(struct iscsit_cmd *,
64 			struct iscsi_scsi_req *, u32);
65 
iscsit_get_tiqn_for_login(unsigned char * buf)66 struct iscsi_tiqn *iscsit_get_tiqn_for_login(unsigned char *buf)
67 {
68 	struct iscsi_tiqn *tiqn = NULL;
69 
70 	spin_lock(&tiqn_lock);
71 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
72 		if (!strcmp(tiqn->tiqn, buf)) {
73 
74 			spin_lock(&tiqn->tiqn_state_lock);
75 			if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
76 				tiqn->tiqn_access_count++;
77 				spin_unlock(&tiqn->tiqn_state_lock);
78 				spin_unlock(&tiqn_lock);
79 				return tiqn;
80 			}
81 			spin_unlock(&tiqn->tiqn_state_lock);
82 		}
83 	}
84 	spin_unlock(&tiqn_lock);
85 
86 	return NULL;
87 }
88 
iscsit_set_tiqn_shutdown(struct iscsi_tiqn * tiqn)89 static int iscsit_set_tiqn_shutdown(struct iscsi_tiqn *tiqn)
90 {
91 	spin_lock(&tiqn->tiqn_state_lock);
92 	if (tiqn->tiqn_state == TIQN_STATE_ACTIVE) {
93 		tiqn->tiqn_state = TIQN_STATE_SHUTDOWN;
94 		spin_unlock(&tiqn->tiqn_state_lock);
95 		return 0;
96 	}
97 	spin_unlock(&tiqn->tiqn_state_lock);
98 
99 	return -1;
100 }
101 
iscsit_put_tiqn_for_login(struct iscsi_tiqn * tiqn)102 void iscsit_put_tiqn_for_login(struct iscsi_tiqn *tiqn)
103 {
104 	spin_lock(&tiqn->tiqn_state_lock);
105 	tiqn->tiqn_access_count--;
106 	spin_unlock(&tiqn->tiqn_state_lock);
107 }
108 
109 /*
110  * Note that IQN formatting is expected to be done in userspace, and
111  * no explict IQN format checks are done here.
112  */
iscsit_add_tiqn(unsigned char * buf)113 struct iscsi_tiqn *iscsit_add_tiqn(unsigned char *buf)
114 {
115 	struct iscsi_tiqn *tiqn = NULL;
116 	int ret;
117 
118 	if (strlen(buf) >= ISCSI_IQN_LEN) {
119 		pr_err("Target IQN exceeds %d bytes\n",
120 				ISCSI_IQN_LEN);
121 		return ERR_PTR(-EINVAL);
122 	}
123 
124 	tiqn = kzalloc_obj(*tiqn);
125 	if (!tiqn)
126 		return ERR_PTR(-ENOMEM);
127 
128 	sprintf(tiqn->tiqn, "%s", buf);
129 	INIT_LIST_HEAD(&tiqn->tiqn_list);
130 	INIT_LIST_HEAD(&tiqn->tiqn_tpg_list);
131 	spin_lock_init(&tiqn->tiqn_state_lock);
132 	spin_lock_init(&tiqn->tiqn_tpg_lock);
133 	spin_lock_init(&tiqn->sess_err_stats.lock);
134 	spin_lock_init(&tiqn->login_stats.lock);
135 	spin_lock_init(&tiqn->logout_stats.lock);
136 
137 	tiqn->tiqn_state = TIQN_STATE_ACTIVE;
138 
139 	idr_preload(GFP_KERNEL);
140 	spin_lock(&tiqn_lock);
141 
142 	ret = idr_alloc(&tiqn_idr, NULL, 0, 0, GFP_NOWAIT);
143 	if (ret < 0) {
144 		pr_err("idr_alloc() failed for tiqn->tiqn_index\n");
145 		spin_unlock(&tiqn_lock);
146 		idr_preload_end();
147 		kfree(tiqn);
148 		return ERR_PTR(ret);
149 	}
150 	tiqn->tiqn_index = ret;
151 	list_add_tail(&tiqn->tiqn_list, &g_tiqn_list);
152 
153 	spin_unlock(&tiqn_lock);
154 	idr_preload_end();
155 
156 	pr_debug("CORE[0] - Added iSCSI Target IQN: %s\n", tiqn->tiqn);
157 
158 	return tiqn;
159 
160 }
161 
iscsit_wait_for_tiqn(struct iscsi_tiqn * tiqn)162 static void iscsit_wait_for_tiqn(struct iscsi_tiqn *tiqn)
163 {
164 	/*
165 	 * Wait for accesses to said struct iscsi_tiqn to end.
166 	 */
167 	spin_lock(&tiqn->tiqn_state_lock);
168 	while (tiqn->tiqn_access_count != 0) {
169 		spin_unlock(&tiqn->tiqn_state_lock);
170 		msleep(10);
171 		spin_lock(&tiqn->tiqn_state_lock);
172 	}
173 	spin_unlock(&tiqn->tiqn_state_lock);
174 }
175 
iscsit_del_tiqn(struct iscsi_tiqn * tiqn)176 void iscsit_del_tiqn(struct iscsi_tiqn *tiqn)
177 {
178 	/*
179 	 * iscsit_set_tiqn_shutdown sets tiqn->tiqn_state = TIQN_STATE_SHUTDOWN
180 	 * while holding tiqn->tiqn_state_lock.  This means that all subsequent
181 	 * attempts to access this struct iscsi_tiqn will fail from both transport
182 	 * fabric and control code paths.
183 	 */
184 	if (iscsit_set_tiqn_shutdown(tiqn) < 0) {
185 		pr_err("iscsit_set_tiqn_shutdown() failed\n");
186 		return;
187 	}
188 
189 	iscsit_wait_for_tiqn(tiqn);
190 
191 	spin_lock(&tiqn_lock);
192 	list_del(&tiqn->tiqn_list);
193 	idr_remove(&tiqn_idr, tiqn->tiqn_index);
194 	spin_unlock(&tiqn_lock);
195 
196 	pr_debug("CORE[0] - Deleted iSCSI Target IQN: %s\n",
197 			tiqn->tiqn);
198 	kfree(tiqn);
199 }
200 
iscsit_access_np(struct iscsi_np * np,struct iscsi_portal_group * tpg)201 int iscsit_access_np(struct iscsi_np *np, struct iscsi_portal_group *tpg)
202 {
203 	int ret;
204 	/*
205 	 * Determine if the network portal is accepting storage traffic.
206 	 */
207 	spin_lock_bh(&np->np_thread_lock);
208 	if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
209 		spin_unlock_bh(&np->np_thread_lock);
210 		return -1;
211 	}
212 	spin_unlock_bh(&np->np_thread_lock);
213 	/*
214 	 * Determine if the portal group is accepting storage traffic.
215 	 */
216 	spin_lock_bh(&tpg->tpg_state_lock);
217 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
218 		spin_unlock_bh(&tpg->tpg_state_lock);
219 		return -1;
220 	}
221 	spin_unlock_bh(&tpg->tpg_state_lock);
222 
223 	/*
224 	 * Here we serialize access across the TIQN+TPG Tuple.
225 	 */
226 	ret = down_interruptible(&tpg->np_login_sem);
227 	if (ret != 0)
228 		return -1;
229 
230 	spin_lock_bh(&tpg->tpg_state_lock);
231 	if (tpg->tpg_state != TPG_STATE_ACTIVE) {
232 		spin_unlock_bh(&tpg->tpg_state_lock);
233 		up(&tpg->np_login_sem);
234 		return -1;
235 	}
236 	spin_unlock_bh(&tpg->tpg_state_lock);
237 
238 	return 0;
239 }
240 
iscsit_login_kref_put(struct kref * kref)241 void iscsit_login_kref_put(struct kref *kref)
242 {
243 	struct iscsi_tpg_np *tpg_np = container_of(kref,
244 				struct iscsi_tpg_np, tpg_np_kref);
245 
246 	complete(&tpg_np->tpg_np_comp);
247 }
248 
iscsit_deaccess_np(struct iscsi_np * np,struct iscsi_portal_group * tpg,struct iscsi_tpg_np * tpg_np)249 int iscsit_deaccess_np(struct iscsi_np *np, struct iscsi_portal_group *tpg,
250 		       struct iscsi_tpg_np *tpg_np)
251 {
252 	struct iscsi_tiqn *tiqn = tpg->tpg_tiqn;
253 
254 	up(&tpg->np_login_sem);
255 
256 	if (tpg_np)
257 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
258 
259 	if (tiqn)
260 		iscsit_put_tiqn_for_login(tiqn);
261 
262 	return 0;
263 }
264 
iscsit_check_np_match(struct sockaddr_storage * sockaddr,struct iscsi_np * np,int network_transport)265 bool iscsit_check_np_match(
266 	struct sockaddr_storage *sockaddr,
267 	struct iscsi_np *np,
268 	int network_transport)
269 {
270 	struct sockaddr_in *sock_in, *sock_in_e;
271 	struct sockaddr_in6 *sock_in6, *sock_in6_e;
272 	bool ip_match = false;
273 	u16 port, port_e;
274 
275 	if (sockaddr->ss_family == AF_INET6) {
276 		sock_in6 = (struct sockaddr_in6 *)sockaddr;
277 		sock_in6_e = (struct sockaddr_in6 *)&np->np_sockaddr;
278 
279 		if (!memcmp(&sock_in6->sin6_addr.in6_u,
280 			    &sock_in6_e->sin6_addr.in6_u,
281 			    sizeof(struct in6_addr)))
282 			ip_match = true;
283 
284 		port = ntohs(sock_in6->sin6_port);
285 		port_e = ntohs(sock_in6_e->sin6_port);
286 	} else {
287 		sock_in = (struct sockaddr_in *)sockaddr;
288 		sock_in_e = (struct sockaddr_in *)&np->np_sockaddr;
289 
290 		if (sock_in->sin_addr.s_addr == sock_in_e->sin_addr.s_addr)
291 			ip_match = true;
292 
293 		port = ntohs(sock_in->sin_port);
294 		port_e = ntohs(sock_in_e->sin_port);
295 	}
296 
297 	if (ip_match && (port_e == port) &&
298 	    (np->np_network_transport == network_transport))
299 		return true;
300 
301 	return false;
302 }
303 
iscsit_get_np(struct sockaddr_storage * sockaddr,int network_transport)304 static struct iscsi_np *iscsit_get_np(
305 	struct sockaddr_storage *sockaddr,
306 	int network_transport)
307 {
308 	struct iscsi_np *np;
309 	bool match;
310 
311 	lockdep_assert_held(&np_lock);
312 
313 	list_for_each_entry(np, &g_np_list, np_list) {
314 		spin_lock_bh(&np->np_thread_lock);
315 		if (np->np_thread_state != ISCSI_NP_THREAD_ACTIVE) {
316 			spin_unlock_bh(&np->np_thread_lock);
317 			continue;
318 		}
319 
320 		match = iscsit_check_np_match(sockaddr, np, network_transport);
321 		if (match) {
322 			/*
323 			 * Increment the np_exports reference count now to
324 			 * prevent iscsit_del_np() below from being called
325 			 * while iscsi_tpg_add_network_portal() is called.
326 			 */
327 			np->np_exports++;
328 			spin_unlock_bh(&np->np_thread_lock);
329 			return np;
330 		}
331 		spin_unlock_bh(&np->np_thread_lock);
332 	}
333 
334 	return NULL;
335 }
336 
iscsit_add_np(struct sockaddr_storage * sockaddr,int network_transport)337 struct iscsi_np *iscsit_add_np(
338 	struct sockaddr_storage *sockaddr,
339 	int network_transport)
340 {
341 	struct iscsi_np *np;
342 	int ret;
343 
344 	mutex_lock(&np_lock);
345 
346 	/*
347 	 * Locate the existing struct iscsi_np if already active..
348 	 */
349 	np = iscsit_get_np(sockaddr, network_transport);
350 	if (np) {
351 		mutex_unlock(&np_lock);
352 		return np;
353 	}
354 
355 	np = kzalloc_obj(*np);
356 	if (!np) {
357 		mutex_unlock(&np_lock);
358 		return ERR_PTR(-ENOMEM);
359 	}
360 
361 	np->np_flags |= NPF_IP_NETWORK;
362 	np->np_network_transport = network_transport;
363 	spin_lock_init(&np->np_thread_lock);
364 	init_completion(&np->np_restart_comp);
365 	INIT_LIST_HEAD(&np->np_list);
366 
367 	ret = iscsi_target_setup_login_socket(np, sockaddr);
368 	if (ret != 0) {
369 		kfree(np);
370 		mutex_unlock(&np_lock);
371 		return ERR_PTR(ret);
372 	}
373 
374 	np->np_thread = kthread_run(iscsi_target_login_thread, np, "iscsi_np");
375 	if (IS_ERR(np->np_thread)) {
376 		pr_err("Unable to create kthread: iscsi_np\n");
377 		ret = PTR_ERR(np->np_thread);
378 		kfree(np);
379 		mutex_unlock(&np_lock);
380 		return ERR_PTR(ret);
381 	}
382 	/*
383 	 * Increment the np_exports reference count now to prevent
384 	 * iscsit_del_np() below from being run while a new call to
385 	 * iscsi_tpg_add_network_portal() for a matching iscsi_np is
386 	 * active.  We don't need to hold np->np_thread_lock at this
387 	 * point because iscsi_np has not been added to g_np_list yet.
388 	 */
389 	np->np_exports = 1;
390 	np->np_thread_state = ISCSI_NP_THREAD_ACTIVE;
391 
392 	list_add_tail(&np->np_list, &g_np_list);
393 	mutex_unlock(&np_lock);
394 
395 	pr_debug("CORE[0] - Added Network Portal: %pISpc on %s\n",
396 		&np->np_sockaddr, np->np_transport->name);
397 
398 	return np;
399 }
400 
iscsit_reset_np_thread(struct iscsi_np * np,struct iscsi_tpg_np * tpg_np,struct iscsi_portal_group * tpg,bool shutdown)401 int iscsit_reset_np_thread(
402 	struct iscsi_np *np,
403 	struct iscsi_tpg_np *tpg_np,
404 	struct iscsi_portal_group *tpg,
405 	bool shutdown)
406 {
407 	spin_lock_bh(&np->np_thread_lock);
408 	if (np->np_thread_state == ISCSI_NP_THREAD_INACTIVE) {
409 		spin_unlock_bh(&np->np_thread_lock);
410 		return 0;
411 	}
412 	np->np_thread_state = ISCSI_NP_THREAD_RESET;
413 	atomic_inc(&np->np_reset_count);
414 
415 	if (np->np_thread) {
416 		spin_unlock_bh(&np->np_thread_lock);
417 		send_sig(SIGINT, np->np_thread, 1);
418 		wait_for_completion(&np->np_restart_comp);
419 		spin_lock_bh(&np->np_thread_lock);
420 	}
421 	spin_unlock_bh(&np->np_thread_lock);
422 
423 	if (tpg_np && shutdown) {
424 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
425 
426 		wait_for_completion(&tpg_np->tpg_np_comp);
427 	}
428 
429 	return 0;
430 }
431 
iscsit_free_np(struct iscsi_np * np)432 static void iscsit_free_np(struct iscsi_np *np)
433 {
434 	if (np->np_socket)
435 		sock_release(np->np_socket);
436 }
437 
iscsit_del_np(struct iscsi_np * np)438 int iscsit_del_np(struct iscsi_np *np)
439 {
440 	spin_lock_bh(&np->np_thread_lock);
441 	np->np_exports--;
442 	if (np->np_exports) {
443 		np->enabled = true;
444 		spin_unlock_bh(&np->np_thread_lock);
445 		return 0;
446 	}
447 	np->np_thread_state = ISCSI_NP_THREAD_SHUTDOWN;
448 	spin_unlock_bh(&np->np_thread_lock);
449 
450 	if (np->np_thread) {
451 		/*
452 		 * We need to send the signal to wakeup Linux/Net
453 		 * which may be sleeping in sock_accept()..
454 		 */
455 		send_sig(SIGINT, np->np_thread, 1);
456 		kthread_stop(np->np_thread);
457 		np->np_thread = NULL;
458 	}
459 
460 	np->np_transport->iscsit_free_np(np);
461 
462 	mutex_lock(&np_lock);
463 	list_del(&np->np_list);
464 	mutex_unlock(&np_lock);
465 
466 	pr_debug("CORE[0] - Removed Network Portal: %pISpc on %s\n",
467 		&np->np_sockaddr, np->np_transport->name);
468 
469 	iscsit_put_transport(np->np_transport);
470 	kfree(np);
471 	return 0;
472 }
473 
474 static void iscsit_get_rx_pdu(struct iscsit_conn *);
475 
iscsit_queue_rsp(struct iscsit_conn * conn,struct iscsit_cmd * cmd)476 int iscsit_queue_rsp(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
477 {
478 	return iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
479 }
480 EXPORT_SYMBOL(iscsit_queue_rsp);
481 
iscsit_aborted_task(struct iscsit_conn * conn,struct iscsit_cmd * cmd)482 void iscsit_aborted_task(struct iscsit_conn *conn, struct iscsit_cmd *cmd)
483 {
484 	spin_lock_bh(&conn->cmd_lock);
485 	if (!list_empty(&cmd->i_conn_node))
486 		list_del_init(&cmd->i_conn_node);
487 	spin_unlock_bh(&conn->cmd_lock);
488 
489 	__iscsit_free_cmd(cmd, true);
490 }
491 EXPORT_SYMBOL(iscsit_aborted_task);
492 
493 static u32 iscsit_crc_buf(const void *buf, u32 payload_length,
494 			  u32 padding, const void *pad_bytes);
495 static void iscsit_tx_thread_wait_for_tcp(struct iscsit_conn *);
496 
497 static int
iscsit_xmit_nondatain_pdu(struct iscsit_conn * conn,struct iscsit_cmd * cmd,const void * data_buf,u32 data_buf_len)498 iscsit_xmit_nondatain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
499 			  const void *data_buf, u32 data_buf_len)
500 {
501 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)cmd->pdu;
502 	struct kvec *iov;
503 	u32 niov = 0, tx_size = ISCSI_HDR_LEN;
504 	int ret;
505 
506 	iov = &cmd->iov_misc[0];
507 	iov[niov].iov_base	= cmd->pdu;
508 	iov[niov++].iov_len	= ISCSI_HDR_LEN;
509 
510 	if (conn->conn_ops->HeaderDigest) {
511 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
512 
513 		*header_digest = iscsit_crc_buf(hdr, ISCSI_HDR_LEN, 0, NULL);
514 
515 		iov[0].iov_len += ISCSI_CRC_LEN;
516 		tx_size += ISCSI_CRC_LEN;
517 		pr_debug("Attaching CRC32C HeaderDigest"
518 			 " to opcode 0x%x 0x%08x\n",
519 			 hdr->opcode, *header_digest);
520 	}
521 
522 	if (data_buf_len) {
523 		u32 padding = ((-data_buf_len) & 3);
524 
525 		iov[niov].iov_base	= (void *)data_buf;
526 		iov[niov++].iov_len	= data_buf_len;
527 		tx_size += data_buf_len;
528 
529 		if (padding != 0) {
530 			iov[niov].iov_base = &cmd->pad_bytes;
531 			iov[niov++].iov_len = padding;
532 			tx_size += padding;
533 			pr_debug("Attaching %u additional"
534 				 " padding bytes.\n", padding);
535 		}
536 
537 		if (conn->conn_ops->DataDigest) {
538 			cmd->data_crc = iscsit_crc_buf(data_buf, data_buf_len,
539 						       padding,
540 						       &cmd->pad_bytes);
541 			iov[niov].iov_base = &cmd->data_crc;
542 			iov[niov++].iov_len = ISCSI_CRC_LEN;
543 			tx_size += ISCSI_CRC_LEN;
544 			pr_debug("Attached DataDigest for %u"
545 				 " bytes opcode 0x%x, CRC 0x%08x\n",
546 				 data_buf_len, hdr->opcode, cmd->data_crc);
547 		}
548 	}
549 
550 	cmd->iov_misc_count = niov;
551 	cmd->tx_size = tx_size;
552 
553 	ret = iscsit_send_tx_data(cmd, conn, 1);
554 	if (ret < 0) {
555 		iscsit_tx_thread_wait_for_tcp(conn);
556 		return ret;
557 	}
558 
559 	return 0;
560 }
561 
562 static int iscsit_map_iovec(struct iscsit_cmd *cmd, struct kvec *iov, int nvec,
563 			    u32 data_offset, u32 data_length);
564 static void iscsit_unmap_iovec(struct iscsit_cmd *);
565 static u32 iscsit_crc_sglist(const struct iscsit_cmd *cmd, u32 data_length,
566 			     u32 padding, const u8 *pad_bytes);
567 static int
iscsit_xmit_datain_pdu(struct iscsit_conn * conn,struct iscsit_cmd * cmd,const struct iscsi_datain * datain)568 iscsit_xmit_datain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
569 		       const struct iscsi_datain *datain)
570 {
571 	struct kvec *iov;
572 	u32 iov_count = 0, tx_size = 0;
573 	int ret, iov_ret;
574 
575 	iov = &cmd->iov_data[0];
576 	iov[iov_count].iov_base	= cmd->pdu;
577 	iov[iov_count++].iov_len = ISCSI_HDR_LEN;
578 	tx_size += ISCSI_HDR_LEN;
579 
580 	if (conn->conn_ops->HeaderDigest) {
581 		u32 *header_digest = (u32 *)&cmd->pdu[ISCSI_HDR_LEN];
582 
583 		*header_digest = iscsit_crc_buf(cmd->pdu, ISCSI_HDR_LEN, 0,
584 						NULL);
585 		iov[0].iov_len += ISCSI_CRC_LEN;
586 		tx_size += ISCSI_CRC_LEN;
587 
588 		pr_debug("Attaching CRC32 HeaderDigest for DataIN PDU 0x%08x\n",
589 			 *header_digest);
590 	}
591 
592 	iov_ret = iscsit_map_iovec(cmd, &cmd->iov_data[iov_count],
593 				   cmd->orig_iov_data_count - (iov_count + 2),
594 				   datain->offset, datain->length);
595 	if (iov_ret < 0)
596 		return -1;
597 
598 	iov_count += iov_ret;
599 	tx_size += datain->length;
600 
601 	cmd->padding = ((-datain->length) & 3);
602 	if (cmd->padding) {
603 		iov[iov_count].iov_base		= cmd->pad_bytes;
604 		iov[iov_count++].iov_len	= cmd->padding;
605 		tx_size += cmd->padding;
606 
607 		pr_debug("Attaching %u padding bytes\n", cmd->padding);
608 	}
609 
610 	if (conn->conn_ops->DataDigest) {
611 		cmd->data_crc = iscsit_crc_sglist(cmd, datain->length,
612 						  cmd->padding, cmd->pad_bytes);
613 		iov[iov_count].iov_base	= &cmd->data_crc;
614 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
615 		tx_size += ISCSI_CRC_LEN;
616 
617 		pr_debug("Attached CRC32C DataDigest %d bytes, crc 0x%08x\n",
618 			 datain->length + cmd->padding, cmd->data_crc);
619 	}
620 
621 	cmd->iov_data_count = iov_count;
622 	cmd->tx_size = tx_size;
623 
624 	ret = iscsit_fe_sendpage_sg(cmd, conn);
625 
626 	iscsit_unmap_iovec(cmd);
627 
628 	if (ret < 0) {
629 		iscsit_tx_thread_wait_for_tcp(conn);
630 		return ret;
631 	}
632 
633 	return 0;
634 }
635 
iscsit_xmit_pdu(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_datain_req * dr,const void * buf,u32 buf_len)636 static int iscsit_xmit_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
637 			   struct iscsi_datain_req *dr, const void *buf,
638 			   u32 buf_len)
639 {
640 	if (dr)
641 		return iscsit_xmit_datain_pdu(conn, cmd, buf);
642 	else
643 		return iscsit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
644 }
645 
iscsit_get_sup_prot_ops(struct iscsit_conn * conn)646 static enum target_prot_op iscsit_get_sup_prot_ops(struct iscsit_conn *conn)
647 {
648 	return TARGET_PROT_NORMAL;
649 }
650 
651 static struct iscsit_transport iscsi_target_transport = {
652 	.name			= "iSCSI/TCP",
653 	.transport_type		= ISCSI_TCP,
654 	.rdma_shutdown		= false,
655 	.owner			= NULL,
656 	.iscsit_setup_np	= iscsit_setup_np,
657 	.iscsit_accept_np	= iscsit_accept_np,
658 	.iscsit_free_np		= iscsit_free_np,
659 	.iscsit_get_login_rx	= iscsit_get_login_rx,
660 	.iscsit_put_login_tx	= iscsit_put_login_tx,
661 	.iscsit_get_dataout	= iscsit_build_r2ts_for_cmd,
662 	.iscsit_immediate_queue	= iscsit_immediate_queue,
663 	.iscsit_response_queue	= iscsit_response_queue,
664 	.iscsit_queue_data_in	= iscsit_queue_rsp,
665 	.iscsit_queue_status	= iscsit_queue_rsp,
666 	.iscsit_aborted_task	= iscsit_aborted_task,
667 	.iscsit_xmit_pdu	= iscsit_xmit_pdu,
668 	.iscsit_get_rx_pdu	= iscsit_get_rx_pdu,
669 	.iscsit_get_sup_prot_ops = iscsit_get_sup_prot_ops,
670 };
671 
iscsi_target_init_module(void)672 static int __init iscsi_target_init_module(void)
673 {
674 	int ret = 0, size;
675 
676 	pr_debug("iSCSI-Target "ISCSIT_VERSION"\n");
677 	iscsit_global = kzalloc_obj(*iscsit_global);
678 	if (!iscsit_global)
679 		return -1;
680 
681 	spin_lock_init(&iscsit_global->ts_bitmap_lock);
682 	mutex_init(&auth_id_lock);
683 	idr_init(&tiqn_idr);
684 
685 	ret = target_register_template(&iscsi_ops);
686 	if (ret)
687 		goto out;
688 
689 	size = BITS_TO_LONGS(ISCSIT_BITMAP_BITS) * sizeof(long);
690 	iscsit_global->ts_bitmap = vzalloc(size);
691 	if (!iscsit_global->ts_bitmap)
692 		goto configfs_out;
693 
694 	if (!zalloc_cpumask_var(&iscsit_global->allowed_cpumask, GFP_KERNEL)) {
695 		pr_err("Unable to allocate iscsit_global->allowed_cpumask\n");
696 		goto bitmap_out;
697 	}
698 	cpumask_setall(iscsit_global->allowed_cpumask);
699 
700 	lio_qr_cache = kmem_cache_create("lio_qr_cache",
701 			sizeof(struct iscsi_queue_req),
702 			__alignof__(struct iscsi_queue_req), 0, NULL);
703 	if (!lio_qr_cache) {
704 		pr_err("Unable to kmem_cache_create() for"
705 				" lio_qr_cache\n");
706 		goto cpumask_out;
707 	}
708 
709 	lio_dr_cache = kmem_cache_create("lio_dr_cache",
710 			sizeof(struct iscsi_datain_req),
711 			__alignof__(struct iscsi_datain_req), 0, NULL);
712 	if (!lio_dr_cache) {
713 		pr_err("Unable to kmem_cache_create() for"
714 				" lio_dr_cache\n");
715 		goto qr_out;
716 	}
717 
718 	lio_ooo_cache = kmem_cache_create("lio_ooo_cache",
719 			sizeof(struct iscsi_ooo_cmdsn),
720 			__alignof__(struct iscsi_ooo_cmdsn), 0, NULL);
721 	if (!lio_ooo_cache) {
722 		pr_err("Unable to kmem_cache_create() for"
723 				" lio_ooo_cache\n");
724 		goto dr_out;
725 	}
726 
727 	lio_r2t_cache = kmem_cache_create("lio_r2t_cache",
728 			sizeof(struct iscsi_r2t), __alignof__(struct iscsi_r2t),
729 			0, NULL);
730 	if (!lio_r2t_cache) {
731 		pr_err("Unable to kmem_cache_create() for"
732 				" lio_r2t_cache\n");
733 		goto ooo_out;
734 	}
735 
736 	iscsit_register_transport(&iscsi_target_transport);
737 
738 	if (iscsit_load_discovery_tpg() < 0)
739 		goto r2t_out;
740 
741 	return ret;
742 r2t_out:
743 	iscsit_unregister_transport(&iscsi_target_transport);
744 	kmem_cache_destroy(lio_r2t_cache);
745 ooo_out:
746 	kmem_cache_destroy(lio_ooo_cache);
747 dr_out:
748 	kmem_cache_destroy(lio_dr_cache);
749 qr_out:
750 	kmem_cache_destroy(lio_qr_cache);
751 cpumask_out:
752 	free_cpumask_var(iscsit_global->allowed_cpumask);
753 bitmap_out:
754 	vfree(iscsit_global->ts_bitmap);
755 configfs_out:
756 	/* XXX: this probably wants it to be it's own unwind step.. */
757 	if (iscsit_global->discovery_tpg)
758 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
759 	target_unregister_template(&iscsi_ops);
760 out:
761 	kfree(iscsit_global);
762 	return -ENOMEM;
763 }
764 
iscsi_target_cleanup_module(void)765 static void __exit iscsi_target_cleanup_module(void)
766 {
767 	iscsit_release_discovery_tpg();
768 	iscsit_unregister_transport(&iscsi_target_transport);
769 	kmem_cache_destroy(lio_qr_cache);
770 	kmem_cache_destroy(lio_dr_cache);
771 	kmem_cache_destroy(lio_ooo_cache);
772 	kmem_cache_destroy(lio_r2t_cache);
773 
774 	/*
775 	 * Shutdown discovery sessions and disable discovery TPG
776 	 */
777 	if (iscsit_global->discovery_tpg)
778 		iscsit_tpg_disable_portal_group(iscsit_global->discovery_tpg, 1);
779 
780 	target_unregister_template(&iscsi_ops);
781 
782 	free_cpumask_var(iscsit_global->allowed_cpumask);
783 	vfree(iscsit_global->ts_bitmap);
784 	kfree(iscsit_global);
785 }
786 
iscsit_add_reject(struct iscsit_conn * conn,u8 reason,unsigned char * buf)787 int iscsit_add_reject(
788 	struct iscsit_conn *conn,
789 	u8 reason,
790 	unsigned char *buf)
791 {
792 	struct iscsit_cmd *cmd;
793 
794 	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
795 	if (!cmd)
796 		return -1;
797 
798 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
799 	cmd->reject_reason = reason;
800 
801 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
802 	if (!cmd->buf_ptr) {
803 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
804 		iscsit_free_cmd(cmd, false);
805 		return -1;
806 	}
807 
808 	spin_lock_bh(&conn->cmd_lock);
809 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
810 	spin_unlock_bh(&conn->cmd_lock);
811 
812 	cmd->i_state = ISTATE_SEND_REJECT;
813 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
814 
815 	return -1;
816 }
817 EXPORT_SYMBOL(iscsit_add_reject);
818 
iscsit_add_reject_from_cmd(struct iscsit_cmd * cmd,u8 reason,bool add_to_conn,unsigned char * buf)819 static int iscsit_add_reject_from_cmd(
820 	struct iscsit_cmd *cmd,
821 	u8 reason,
822 	bool add_to_conn,
823 	unsigned char *buf)
824 {
825 	struct iscsit_conn *conn;
826 	const bool do_put = cmd->se_cmd.se_tfo != NULL;
827 
828 	if (!cmd->conn) {
829 		pr_err("cmd->conn is NULL for ITT: 0x%08x\n",
830 				cmd->init_task_tag);
831 		return -1;
832 	}
833 	conn = cmd->conn;
834 
835 	cmd->iscsi_opcode = ISCSI_OP_REJECT;
836 	cmd->reject_reason = reason;
837 
838 	cmd->buf_ptr = kmemdup(buf, ISCSI_HDR_LEN, GFP_KERNEL);
839 	if (!cmd->buf_ptr) {
840 		pr_err("Unable to allocate memory for cmd->buf_ptr\n");
841 		iscsit_free_cmd(cmd, false);
842 		return -1;
843 	}
844 
845 	if (add_to_conn) {
846 		spin_lock_bh(&conn->cmd_lock);
847 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
848 		spin_unlock_bh(&conn->cmd_lock);
849 	}
850 
851 	cmd->i_state = ISTATE_SEND_REJECT;
852 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
853 	/*
854 	 * Perform the kref_put now if se_cmd has already been setup by
855 	 * scsit_setup_scsi_cmd()
856 	 */
857 	if (do_put) {
858 		pr_debug("iscsi reject: calling target_put_sess_cmd >>>>>>\n");
859 		target_put_sess_cmd(&cmd->se_cmd);
860 	}
861 	return -1;
862 }
863 
iscsit_add_reject_cmd(struct iscsit_cmd * cmd,u8 reason,unsigned char * buf)864 static int iscsit_add_reject_cmd(struct iscsit_cmd *cmd, u8 reason,
865 				 unsigned char *buf)
866 {
867 	return iscsit_add_reject_from_cmd(cmd, reason, true, buf);
868 }
869 
iscsit_reject_cmd(struct iscsit_cmd * cmd,u8 reason,unsigned char * buf)870 int iscsit_reject_cmd(struct iscsit_cmd *cmd, u8 reason, unsigned char *buf)
871 {
872 	return iscsit_add_reject_from_cmd(cmd, reason, false, buf);
873 }
874 EXPORT_SYMBOL(iscsit_reject_cmd);
875 
876 /*
877  * Map some portion of the allocated scatterlist to an iovec, suitable for
878  * kernel sockets to copy data in/out.
879  */
iscsit_map_iovec(struct iscsit_cmd * cmd,struct kvec * iov,int nvec,u32 data_offset,u32 data_length)880 static int iscsit_map_iovec(struct iscsit_cmd *cmd, struct kvec *iov, int nvec,
881 			    u32 data_offset, u32 data_length)
882 {
883 	u32 i = 0, orig_data_length = data_length;
884 	struct scatterlist *sg;
885 	unsigned int page_off;
886 
887 	/*
888 	 * We know each entry in t_data_sg contains a page.
889 	 */
890 	u32 ent = data_offset / PAGE_SIZE;
891 
892 	if (!data_length)
893 		return 0;
894 
895 	if (ent >= cmd->se_cmd.t_data_nents) {
896 		pr_err("Initial page entry out-of-bounds\n");
897 		goto overflow;
898 	}
899 
900 	sg = &cmd->se_cmd.t_data_sg[ent];
901 	page_off = (data_offset % PAGE_SIZE);
902 
903 	cmd->first_data_sg = sg;
904 	cmd->first_data_sg_off = page_off;
905 
906 	while (data_length) {
907 		u32 cur_len;
908 
909 		if (WARN_ON_ONCE(!sg || i >= nvec))
910 			goto overflow;
911 
912 		cur_len = min_t(u32, data_length, sg->length - page_off);
913 
914 		iov[i].iov_base = kmap(sg_page(sg)) + sg->offset + page_off;
915 		iov[i].iov_len = cur_len;
916 
917 		data_length -= cur_len;
918 		page_off = 0;
919 		sg = sg_next(sg);
920 		i++;
921 	}
922 
923 	cmd->kmapped_nents = i;
924 
925 	return i;
926 
927 overflow:
928 	pr_err("offset %d + length %d overflow; %d/%d; sg-list:\n",
929 	       data_offset, orig_data_length, i, nvec);
930 	for_each_sg(cmd->se_cmd.t_data_sg, sg,
931 		    cmd->se_cmd.t_data_nents, i) {
932 		pr_err("[%d] off %d len %d\n",
933 		       i, sg->offset, sg->length);
934 	}
935 	return -1;
936 }
937 
iscsit_unmap_iovec(struct iscsit_cmd * cmd)938 static void iscsit_unmap_iovec(struct iscsit_cmd *cmd)
939 {
940 	u32 i;
941 	struct scatterlist *sg;
942 
943 	sg = cmd->first_data_sg;
944 
945 	for (i = 0; i < cmd->kmapped_nents; i++)
946 		kunmap(sg_page(&sg[i]));
947 }
948 
iscsit_ack_from_expstatsn(struct iscsit_conn * conn,u32 exp_statsn)949 static void iscsit_ack_from_expstatsn(struct iscsit_conn *conn, u32 exp_statsn)
950 {
951 	LIST_HEAD(ack_list);
952 	struct iscsit_cmd *cmd, *cmd_p;
953 
954 	conn->exp_statsn = exp_statsn;
955 
956 	if (conn->sess->sess_ops->RDMAExtensions)
957 		return;
958 
959 	spin_lock_bh(&conn->cmd_lock);
960 	list_for_each_entry_safe(cmd, cmd_p, &conn->conn_cmd_list, i_conn_node) {
961 		spin_lock(&cmd->istate_lock);
962 		if ((cmd->i_state == ISTATE_SENT_STATUS) &&
963 		    iscsi_sna_lt(cmd->stat_sn, exp_statsn)) {
964 			cmd->i_state = ISTATE_REMOVE;
965 			spin_unlock(&cmd->istate_lock);
966 			list_move_tail(&cmd->i_conn_node, &ack_list);
967 			continue;
968 		}
969 		spin_unlock(&cmd->istate_lock);
970 	}
971 	spin_unlock_bh(&conn->cmd_lock);
972 
973 	list_for_each_entry_safe(cmd, cmd_p, &ack_list, i_conn_node) {
974 		list_del_init(&cmd->i_conn_node);
975 		iscsit_free_cmd(cmd, false);
976 	}
977 }
978 
iscsit_allocate_iovecs(struct iscsit_cmd * cmd)979 static int iscsit_allocate_iovecs(struct iscsit_cmd *cmd)
980 {
981 	u32 iov_count = max(1UL, DIV_ROUND_UP(cmd->se_cmd.data_length, PAGE_SIZE));
982 
983 	iov_count += ISCSI_IOV_DATA_BUFFER;
984 	cmd->iov_data = kzalloc_objs(*cmd->iov_data, iov_count);
985 	if (!cmd->iov_data)
986 		return -ENOMEM;
987 
988 	cmd->orig_iov_data_count = iov_count;
989 	return 0;
990 }
991 
iscsit_setup_scsi_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)992 int iscsit_setup_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
993 			  unsigned char *buf)
994 {
995 	int data_direction, payload_length;
996 	struct iscsi_ecdb_ahdr *ecdb_ahdr;
997 	struct iscsi_scsi_req *hdr;
998 	u16 ahslength, cdb_length;
999 	int iscsi_task_attr;
1000 	unsigned char *cdb;
1001 	int sam_task_attr;
1002 
1003 	atomic_long_inc(&conn->sess->cmd_pdus);
1004 
1005 	hdr			= (struct iscsi_scsi_req *) buf;
1006 	payload_length		= ntoh24(hdr->dlength);
1007 
1008 	/* FIXME; Add checks for AdditionalHeaderSegment */
1009 
1010 	if (!(hdr->flags & ISCSI_FLAG_CMD_WRITE) &&
1011 	    !(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1012 		pr_err("ISCSI_FLAG_CMD_WRITE & ISCSI_FLAG_CMD_FINAL"
1013 				" not set. Bad iSCSI Initiator.\n");
1014 		return iscsit_add_reject_cmd(cmd,
1015 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1016 	}
1017 
1018 	if (((hdr->flags & ISCSI_FLAG_CMD_READ) ||
1019 	     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) && !hdr->data_length) {
1020 		/*
1021 		 * From RFC-3720 Section 10.3.1:
1022 		 *
1023 		 * "Either or both of R and W MAY be 1 when either the
1024 		 *  Expected Data Transfer Length and/or Bidirectional Read
1025 		 *  Expected Data Transfer Length are 0"
1026 		 *
1027 		 * For this case, go ahead and clear the unnecssary bits
1028 		 * to avoid any confusion with ->data_direction.
1029 		 */
1030 		hdr->flags &= ~ISCSI_FLAG_CMD_READ;
1031 		hdr->flags &= ~ISCSI_FLAG_CMD_WRITE;
1032 
1033 		pr_warn("ISCSI_FLAG_CMD_READ or ISCSI_FLAG_CMD_WRITE"
1034 			" set when Expected Data Transfer Length is 0 for"
1035 			" CDB: 0x%02x, Fixing up flags\n", hdr->cdb[0]);
1036 	}
1037 
1038 	if (!(hdr->flags & ISCSI_FLAG_CMD_READ) &&
1039 	    !(hdr->flags & ISCSI_FLAG_CMD_WRITE) && (hdr->data_length != 0)) {
1040 		pr_err("ISCSI_FLAG_CMD_READ and/or ISCSI_FLAG_CMD_WRITE"
1041 			" MUST be set if Expected Data Transfer Length is not 0."
1042 			" Bad iSCSI Initiator\n");
1043 		return iscsit_add_reject_cmd(cmd,
1044 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1045 	}
1046 
1047 	if ((hdr->flags & ISCSI_FLAG_CMD_READ) &&
1048 	    (hdr->flags & ISCSI_FLAG_CMD_WRITE)) {
1049 		pr_err("Bidirectional operations not supported!\n");
1050 		return iscsit_add_reject_cmd(cmd,
1051 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1052 	}
1053 
1054 	if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1055 		pr_err("Illegally set Immediate Bit in iSCSI Initiator"
1056 				" Scsi Command PDU.\n");
1057 		return iscsit_add_reject_cmd(cmd,
1058 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1059 	}
1060 
1061 	if (payload_length && !conn->sess->sess_ops->ImmediateData) {
1062 		pr_err("ImmediateData=No but DataSegmentLength=%u,"
1063 			" protocol error.\n", payload_length);
1064 		return iscsit_add_reject_cmd(cmd,
1065 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1066 	}
1067 
1068 	if ((be32_to_cpu(hdr->data_length) == payload_length) &&
1069 	    (!(hdr->flags & ISCSI_FLAG_CMD_FINAL))) {
1070 		pr_err("Expected Data Transfer Length and Length of"
1071 			" Immediate Data are the same, but ISCSI_FLAG_CMD_FINAL"
1072 			" bit is not set protocol error\n");
1073 		return iscsit_add_reject_cmd(cmd,
1074 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1075 	}
1076 
1077 	if (payload_length > be32_to_cpu(hdr->data_length)) {
1078 		pr_err("DataSegmentLength: %u is greater than"
1079 			" EDTL: %u, protocol error.\n", payload_length,
1080 				hdr->data_length);
1081 		return iscsit_add_reject_cmd(cmd,
1082 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1083 	}
1084 
1085 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1086 		pr_err("DataSegmentLength: %u is greater than"
1087 			" MaxXmitDataSegmentLength: %u, protocol error.\n",
1088 			payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
1089 		return iscsit_add_reject_cmd(cmd,
1090 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
1091 	}
1092 
1093 	if (payload_length > conn->sess->sess_ops->FirstBurstLength) {
1094 		pr_err("DataSegmentLength: %u is greater than"
1095 			" FirstBurstLength: %u, protocol error.\n",
1096 			payload_length, conn->sess->sess_ops->FirstBurstLength);
1097 		return iscsit_add_reject_cmd(cmd,
1098 					     ISCSI_REASON_BOOKMARK_INVALID, buf);
1099 	}
1100 
1101 	cdb = hdr->cdb;
1102 
1103 	if (hdr->hlength) {
1104 		ecdb_ahdr = (struct iscsi_ecdb_ahdr *) (hdr + 1);
1105 		if (ecdb_ahdr->ahstype != ISCSI_AHSTYPE_CDB) {
1106 			pr_err("Additional Header Segment type %d not supported!\n",
1107 			       ecdb_ahdr->ahstype);
1108 			return iscsit_add_reject_cmd(cmd,
1109 				ISCSI_REASON_CMD_NOT_SUPPORTED, buf);
1110 		}
1111 
1112 		ahslength = be16_to_cpu(ecdb_ahdr->ahslength);
1113 		if (!ahslength) {
1114 			pr_err("Extended CDB AHS with zero length, protocol error.\n");
1115 			return iscsit_add_reject_cmd(cmd,
1116 				ISCSI_REASON_PROTOCOL_ERROR, buf);
1117 		}
1118 		if (ahslength > (hdr->hlength * 4) - 3) {
1119 			pr_err("Extended CDB AHS length %u exceeds available PDU buffer.\n",
1120 			       ahslength);
1121 			return iscsit_add_reject_cmd(cmd,
1122 				ISCSI_REASON_PROTOCOL_ERROR, buf);
1123 		}
1124 
1125 		cdb_length = ahslength - 1 + ISCSI_CDB_SIZE;
1126 
1127 		cdb = kmalloc(cdb_length, GFP_KERNEL);
1128 		if (cdb == NULL)
1129 			return iscsit_add_reject_cmd(cmd,
1130 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1131 		memcpy(cdb, hdr->cdb, ISCSI_CDB_SIZE);
1132 		memcpy(cdb + ISCSI_CDB_SIZE, ecdb_ahdr->ecdb, cdb_length - ISCSI_CDB_SIZE);
1133 	}
1134 
1135 	data_direction = (hdr->flags & ISCSI_FLAG_CMD_WRITE) ? DMA_TO_DEVICE :
1136 			 (hdr->flags & ISCSI_FLAG_CMD_READ) ? DMA_FROM_DEVICE :
1137 			  DMA_NONE;
1138 
1139 	cmd->data_direction = data_direction;
1140 	iscsi_task_attr = hdr->flags & ISCSI_FLAG_CMD_ATTR_MASK;
1141 	/*
1142 	 * Figure out the SAM Task Attribute for the incoming SCSI CDB
1143 	 */
1144 	if ((iscsi_task_attr == ISCSI_ATTR_UNTAGGED) ||
1145 	    (iscsi_task_attr == ISCSI_ATTR_SIMPLE))
1146 		sam_task_attr = TCM_SIMPLE_TAG;
1147 	else if (iscsi_task_attr == ISCSI_ATTR_ORDERED)
1148 		sam_task_attr = TCM_ORDERED_TAG;
1149 	else if (iscsi_task_attr == ISCSI_ATTR_HEAD_OF_QUEUE)
1150 		sam_task_attr = TCM_HEAD_TAG;
1151 	else if (iscsi_task_attr == ISCSI_ATTR_ACA)
1152 		sam_task_attr = TCM_ACA_TAG;
1153 	else {
1154 		pr_debug("Unknown iSCSI Task Attribute: 0x%02x, using"
1155 			" TCM_SIMPLE_TAG\n", iscsi_task_attr);
1156 		sam_task_attr = TCM_SIMPLE_TAG;
1157 	}
1158 
1159 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_CMD;
1160 	cmd->i_state		= ISTATE_NEW_CMD;
1161 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
1162 	cmd->immediate_data	= (payload_length) ? 1 : 0;
1163 	cmd->unsolicited_data	= ((!(hdr->flags & ISCSI_FLAG_CMD_FINAL) &&
1164 				     (hdr->flags & ISCSI_FLAG_CMD_WRITE)) ? 1 : 0);
1165 	if (cmd->unsolicited_data)
1166 		cmd->cmd_flags |= ICF_NON_IMMEDIATE_UNSOLICITED_DATA;
1167 
1168 	conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1169 	if (hdr->flags & ISCSI_FLAG_CMD_READ)
1170 		cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
1171 	else
1172 		cmd->targ_xfer_tag = 0xFFFFFFFF;
1173 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1174 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1175 	cmd->first_burst_len	= payload_length;
1176 
1177 	if (!conn->sess->sess_ops->RDMAExtensions &&
1178 	     cmd->data_direction == DMA_FROM_DEVICE) {
1179 		struct iscsi_datain_req *dr;
1180 
1181 		dr = iscsit_allocate_datain_req();
1182 		if (!dr) {
1183 			if (cdb != hdr->cdb)
1184 				kfree(cdb);
1185 			return iscsit_add_reject_cmd(cmd,
1186 					ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1187 		}
1188 
1189 		iscsit_attach_datain_req(cmd, dr);
1190 	}
1191 
1192 	/*
1193 	 * Initialize struct se_cmd descriptor from target_core_mod infrastructure
1194 	 */
1195 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
1196 			  conn->sess->se_sess, be32_to_cpu(hdr->data_length),
1197 			  cmd->data_direction, sam_task_attr,
1198 			  cmd->sense_buffer + 2, scsilun_to_int(&hdr->lun),
1199 			  conn->cmd_cnt);
1200 
1201 	pr_debug("Got SCSI Command, ITT: 0x%08x, CmdSN: 0x%08x,"
1202 		" ExpXferLen: %u, Length: %u, CID: %hu\n", hdr->itt,
1203 		hdr->cmdsn, be32_to_cpu(hdr->data_length), payload_length,
1204 		conn->cid);
1205 
1206 	target_get_sess_cmd(&cmd->se_cmd, true);
1207 
1208 	cmd->se_cmd.tag = (__force u32)cmd->init_task_tag;
1209 	cmd->sense_reason = target_cmd_init_cdb(&cmd->se_cmd, cdb,
1210 						GFP_KERNEL);
1211 
1212 	if (cdb != hdr->cdb)
1213 		kfree(cdb);
1214 
1215 	if (cmd->sense_reason) {
1216 		if (cmd->sense_reason == TCM_OUT_OF_RESOURCES) {
1217 			return iscsit_add_reject_cmd(cmd,
1218 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1219 		}
1220 
1221 		goto attach_cmd;
1222 	}
1223 
1224 	cmd->sense_reason = transport_lookup_cmd_lun(&cmd->se_cmd);
1225 	if (cmd->sense_reason)
1226 		goto attach_cmd;
1227 
1228 	cmd->sense_reason = target_cmd_parse_cdb(&cmd->se_cmd);
1229 	if (cmd->sense_reason)
1230 		goto attach_cmd;
1231 
1232 	if (iscsit_build_pdu_and_seq_lists(cmd, payload_length) < 0) {
1233 		return iscsit_add_reject_cmd(cmd,
1234 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1235 	}
1236 
1237 attach_cmd:
1238 	spin_lock_bh(&conn->cmd_lock);
1239 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1240 	spin_unlock_bh(&conn->cmd_lock);
1241 	return 0;
1242 }
1243 EXPORT_SYMBOL(iscsit_setup_scsi_cmd);
1244 
iscsit_set_unsolicited_dataout(struct iscsit_cmd * cmd)1245 void iscsit_set_unsolicited_dataout(struct iscsit_cmd *cmd)
1246 {
1247 	iscsit_set_dataout_sequence_values(cmd);
1248 
1249 	spin_lock_bh(&cmd->dataout_timeout_lock);
1250 	iscsit_start_dataout_timer(cmd, cmd->conn);
1251 	spin_unlock_bh(&cmd->dataout_timeout_lock);
1252 }
1253 EXPORT_SYMBOL(iscsit_set_unsolicited_dataout);
1254 
iscsit_process_scsi_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_scsi_req * hdr)1255 int iscsit_process_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1256 			    struct iscsi_scsi_req *hdr)
1257 {
1258 	int cmdsn_ret = 0;
1259 	/*
1260 	 * Check the CmdSN against ExpCmdSN/MaxCmdSN here if
1261 	 * the Immediate Bit is not set, and no Immediate
1262 	 * Data is attached.
1263 	 *
1264 	 * A PDU/CmdSN carrying Immediate Data can only
1265 	 * be processed after the DataCRC has passed.
1266 	 * If the DataCRC fails, the CmdSN MUST NOT
1267 	 * be acknowledged. (See below)
1268 	 */
1269 	if (!cmd->immediate_data) {
1270 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1271 					(unsigned char *)hdr, hdr->cmdsn);
1272 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1273 			return -1;
1274 		else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1275 			target_put_sess_cmd(&cmd->se_cmd);
1276 			return 0;
1277 		}
1278 	}
1279 
1280 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1281 
1282 	/*
1283 	 * If no Immediate Data is attached, it's OK to return now.
1284 	 */
1285 	if (!cmd->immediate_data) {
1286 		if (!cmd->sense_reason && cmd->unsolicited_data)
1287 			iscsit_set_unsolicited_dataout(cmd);
1288 		if (!cmd->sense_reason)
1289 			return 0;
1290 
1291 		target_put_sess_cmd(&cmd->se_cmd);
1292 		return 0;
1293 	}
1294 
1295 	/*
1296 	 * Early CHECK_CONDITIONs with ImmediateData never make it to command
1297 	 * execution.  These exceptions are processed in CmdSN order using
1298 	 * iscsit_check_received_cmdsn() in iscsit_get_immediate_data() below.
1299 	 */
1300 	if (cmd->sense_reason)
1301 		return 1;
1302 	/*
1303 	 * Call directly into transport_generic_new_cmd() to perform
1304 	 * the backend memory allocation.
1305 	 */
1306 	cmd->sense_reason = transport_generic_new_cmd(&cmd->se_cmd);
1307 	if (cmd->sense_reason)
1308 		return 1;
1309 
1310 	return 0;
1311 }
1312 EXPORT_SYMBOL(iscsit_process_scsi_cmd);
1313 
1314 static int
iscsit_get_immediate_data(struct iscsit_cmd * cmd,struct iscsi_scsi_req * hdr,bool dump_payload)1315 iscsit_get_immediate_data(struct iscsit_cmd *cmd, struct iscsi_scsi_req *hdr,
1316 			  bool dump_payload)
1317 {
1318 	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
1319 	int rc;
1320 
1321 	/*
1322 	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
1323 	 */
1324 	if (dump_payload) {
1325 		u32 length = min(cmd->se_cmd.data_length - cmd->write_data_done,
1326 				 cmd->first_burst_len);
1327 
1328 		pr_debug("Dumping min(%d - %d, %d) = %d bytes of immediate data\n",
1329 			 cmd->se_cmd.data_length, cmd->write_data_done,
1330 			 cmd->first_burst_len, length);
1331 		rc = iscsit_dump_data_payload(cmd->conn, length, 1);
1332 		pr_debug("Finished dumping immediate data\n");
1333 		if (rc < 0)
1334 			immed_ret = IMMEDIATE_DATA_CANNOT_RECOVER;
1335 	} else {
1336 		immed_ret = iscsit_handle_immediate_data(cmd, hdr,
1337 							 cmd->first_burst_len);
1338 	}
1339 
1340 	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
1341 		/*
1342 		 * A PDU/CmdSN carrying Immediate Data passed
1343 		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
1344 		 * Immediate Bit is not set.
1345 		 */
1346 		cmdsn_ret = iscsit_sequence_cmd(cmd->conn, cmd,
1347 					(unsigned char *)hdr, hdr->cmdsn);
1348 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1349 			return -1;
1350 
1351 		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
1352 			target_put_sess_cmd(&cmd->se_cmd);
1353 
1354 			return 0;
1355 		} else if (cmd->unsolicited_data)
1356 			iscsit_set_unsolicited_dataout(cmd);
1357 
1358 	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
1359 		/*
1360 		 * Immediate Data failed DataCRC and ERL>=1,
1361 		 * silently drop this PDU and let the initiator
1362 		 * plug the CmdSN gap.
1363 		 *
1364 		 * FIXME: Send Unsolicited NOPIN with reserved
1365 		 * TTT here to help the initiator figure out
1366 		 * the missing CmdSN, although they should be
1367 		 * intelligent enough to determine the missing
1368 		 * CmdSN and issue a retry to plug the sequence.
1369 		 */
1370 		cmd->i_state = ISTATE_REMOVE;
1371 		iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, cmd->i_state);
1372 	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
1373 		return -1;
1374 
1375 	return 0;
1376 }
1377 
1378 static int
iscsit_handle_scsi_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)1379 iscsit_handle_scsi_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1380 			   unsigned char *buf)
1381 {
1382 	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)buf;
1383 	int rc, immed_data;
1384 	bool dump_payload = false;
1385 
1386 	rc = iscsit_setup_scsi_cmd(conn, cmd, buf);
1387 	if (rc < 0)
1388 		return 0;
1389 	/*
1390 	 * Allocation iovecs needed for struct socket operations for
1391 	 * traditional iSCSI block I/O.
1392 	 */
1393 	if (iscsit_allocate_iovecs(cmd) < 0) {
1394 		return iscsit_reject_cmd(cmd,
1395 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
1396 	}
1397 	immed_data = cmd->immediate_data;
1398 
1399 	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
1400 	if (rc < 0)
1401 		return rc;
1402 	else if (rc > 0)
1403 		dump_payload = true;
1404 
1405 	if (!immed_data)
1406 		return 0;
1407 
1408 	return iscsit_get_immediate_data(cmd, hdr, dump_payload);
1409 }
1410 
iscsit_crc_sglist(const struct iscsit_cmd * cmd,u32 data_length,u32 padding,const u8 * pad_bytes)1411 static u32 iscsit_crc_sglist(const struct iscsit_cmd *cmd, u32 data_length,
1412 			     u32 padding, const u8 *pad_bytes)
1413 {
1414 	struct scatterlist *sg = cmd->first_data_sg;
1415 	unsigned int page_off = cmd->first_data_sg_off;
1416 	u32 crc = ~0;
1417 
1418 	while (data_length) {
1419 		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
1420 		const void *virt;
1421 
1422 		virt = kmap_local_page(sg_page(sg)) + sg->offset + page_off;
1423 		crc = crc32c(crc, virt, cur_len);
1424 		kunmap_local(virt);
1425 
1426 		/* iscsit_map_iovec has already checked for invalid sg pointers */
1427 		sg = sg_next(sg);
1428 
1429 		page_off = 0;
1430 		data_length -= cur_len;
1431 	}
1432 
1433 	if (padding)
1434 		crc = crc32c(crc, pad_bytes, padding);
1435 
1436 	return ~crc;
1437 }
1438 
iscsit_crc_buf(const void * buf,u32 payload_length,u32 padding,const void * pad_bytes)1439 static u32 iscsit_crc_buf(const void *buf, u32 payload_length,
1440 			  u32 padding, const void *pad_bytes)
1441 {
1442 	u32 crc = ~0;
1443 
1444 	crc = crc32c(crc, buf, payload_length);
1445 
1446 	if (padding)
1447 		crc = crc32c(crc, pad_bytes, padding);
1448 
1449 	return ~crc;
1450 }
1451 
1452 int
__iscsit_check_dataout_hdr(struct iscsit_conn * conn,void * buf,struct iscsit_cmd * cmd,u32 payload_length,bool * success)1453 __iscsit_check_dataout_hdr(struct iscsit_conn *conn, void *buf,
1454 			   struct iscsit_cmd *cmd, u32 payload_length,
1455 			   bool *success)
1456 {
1457 	struct iscsi_data *hdr = buf;
1458 	struct se_cmd *se_cmd;
1459 	int rc;
1460 
1461 	/* iSCSI write */
1462 	atomic_long_add(payload_length, &conn->sess->rx_data_octets);
1463 
1464 	pr_debug("Got DataOut ITT: 0x%08x, TTT: 0x%08x,"
1465 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
1466 		hdr->itt, hdr->ttt, hdr->datasn, ntohl(hdr->offset),
1467 		payload_length, conn->cid);
1468 
1469 	if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
1470 		pr_err("Command ITT: 0x%08x received DataOUT after"
1471 			" last DataOUT received, dumping payload\n",
1472 			cmd->init_task_tag);
1473 		return iscsit_dump_data_payload(conn, payload_length, 1);
1474 	}
1475 
1476 	if (cmd->data_direction != DMA_TO_DEVICE) {
1477 		pr_err("Command ITT: 0x%08x received DataOUT for a"
1478 			" NON-WRITE command.\n", cmd->init_task_tag);
1479 		return iscsit_dump_data_payload(conn, payload_length, 1);
1480 	}
1481 	se_cmd = &cmd->se_cmd;
1482 	iscsit_mod_dataout_timer(cmd);
1483 
1484 	if ((be32_to_cpu(hdr->offset) + payload_length) > cmd->se_cmd.data_length) {
1485 		pr_err("DataOut Offset: %u, Length %u greater than iSCSI Command EDTL %u, protocol error.\n",
1486 		       be32_to_cpu(hdr->offset), payload_length,
1487 		       cmd->se_cmd.data_length);
1488 		return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID, buf);
1489 	}
1490 
1491 	if (cmd->unsolicited_data) {
1492 		int dump_unsolicited_data = 0;
1493 
1494 		if (conn->sess->sess_ops->InitialR2T) {
1495 			pr_err("Received unexpected unsolicited data"
1496 				" while InitialR2T=Yes, protocol error.\n");
1497 			transport_send_check_condition_and_sense(&cmd->se_cmd,
1498 					TCM_UNEXPECTED_UNSOLICITED_DATA, 0);
1499 			return -1;
1500 		}
1501 		/*
1502 		 * Special case for dealing with Unsolicited DataOUT
1503 		 * and Unsupported SAM WRITE Opcodes and SE resource allocation
1504 		 * failures;
1505 		 */
1506 
1507 		/* Something's amiss if we're not in WRITE_PENDING state... */
1508 		WARN_ON(se_cmd->t_state != TRANSPORT_WRITE_PENDING);
1509 		if (!(se_cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE))
1510 			dump_unsolicited_data = 1;
1511 
1512 		if (dump_unsolicited_data) {
1513 			/*
1514 			 * Check if a delayed TASK_ABORTED status needs to
1515 			 * be sent now if the ISCSI_FLAG_CMD_FINAL has been
1516 			 * received with the unsolicited data out.
1517 			 */
1518 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL)
1519 				iscsit_stop_dataout_timer(cmd);
1520 
1521 			return iscsit_dump_data_payload(conn, payload_length, 1);
1522 		}
1523 	} else {
1524 		/*
1525 		 * For the normal solicited data path:
1526 		 *
1527 		 * Check for a delayed TASK_ABORTED status and dump any
1528 		 * incoming data out payload if one exists.  Also, when the
1529 		 * ISCSI_FLAG_CMD_FINAL is set to denote the end of the current
1530 		 * data out sequence, we decrement outstanding_r2ts.  Once
1531 		 * outstanding_r2ts reaches zero, go ahead and send the delayed
1532 		 * TASK_ABORTED status.
1533 		 */
1534 		if (se_cmd->transport_state & CMD_T_ABORTED) {
1535 			if (hdr->flags & ISCSI_FLAG_CMD_FINAL &&
1536 			    --cmd->outstanding_r2ts < 1)
1537 				iscsit_stop_dataout_timer(cmd);
1538 
1539 			return iscsit_dump_data_payload(conn, payload_length, 1);
1540 		}
1541 	}
1542 	/*
1543 	 * Perform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1544 	 * within-command recovery checks before receiving the payload.
1545 	 */
1546 	rc = iscsit_check_pre_dataout(cmd, buf);
1547 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1548 		return 0;
1549 	else if (rc == DATAOUT_CANNOT_RECOVER)
1550 		return -1;
1551 	*success = true;
1552 	return 0;
1553 }
1554 EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
1555 
1556 int
iscsit_check_dataout_hdr(struct iscsit_conn * conn,void * buf,struct iscsit_cmd ** out_cmd)1557 iscsit_check_dataout_hdr(struct iscsit_conn *conn, void *buf,
1558 			 struct iscsit_cmd **out_cmd)
1559 {
1560 	struct iscsi_data *hdr = buf;
1561 	struct iscsit_cmd *cmd;
1562 	u32 payload_length = ntoh24(hdr->dlength);
1563 	int rc;
1564 	bool success = false;
1565 
1566 	if (!payload_length) {
1567 		pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
1568 		return 0;
1569 	}
1570 
1571 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1572 		pr_err_ratelimited("DataSegmentLength: %u is greater than"
1573 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1574 			conn->conn_ops->MaxXmitDataSegmentLength);
1575 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
1576 	}
1577 
1578 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
1579 	if (!cmd)
1580 		return 0;
1581 
1582 	rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
1583 
1584 	if (success)
1585 		*out_cmd = cmd;
1586 
1587 	return rc;
1588 }
1589 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1590 
1591 static int
iscsit_get_dataout(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_data * hdr)1592 iscsit_get_dataout(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1593 		   struct iscsi_data *hdr)
1594 {
1595 	struct kvec *iov;
1596 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1597 	u32 payload_length;
1598 	int iov_ret, data_crc_failed = 0;
1599 
1600 	payload_length = min_t(u32, cmd->se_cmd.data_length,
1601 			       ntoh24(hdr->dlength));
1602 	rx_size += payload_length;
1603 	iov = &cmd->iov_data[0];
1604 
1605 	iov_ret = iscsit_map_iovec(cmd, iov, cmd->orig_iov_data_count - 2,
1606 				   be32_to_cpu(hdr->offset), payload_length);
1607 	if (iov_ret < 0)
1608 		return -1;
1609 
1610 	iov_count += iov_ret;
1611 
1612 	padding = ((-payload_length) & 3);
1613 	if (padding != 0) {
1614 		iov[iov_count].iov_base	= cmd->pad_bytes;
1615 		iov[iov_count++].iov_len = padding;
1616 		rx_size += padding;
1617 		pr_debug("Receiving %u padding bytes.\n", padding);
1618 	}
1619 
1620 	if (conn->conn_ops->DataDigest) {
1621 		iov[iov_count].iov_base = &checksum;
1622 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1623 		rx_size += ISCSI_CRC_LEN;
1624 	}
1625 
1626 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
1627 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1628 
1629 	iscsit_unmap_iovec(cmd);
1630 
1631 	if (rx_got != rx_size)
1632 		return -1;
1633 
1634 	if (conn->conn_ops->DataDigest) {
1635 		u32 data_crc;
1636 
1637 		data_crc = iscsit_crc_sglist(cmd, payload_length, padding,
1638 					     cmd->pad_bytes);
1639 		if (checksum != data_crc) {
1640 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1641 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1642 				" does not match computed 0x%08x\n",
1643 				hdr->itt, hdr->offset, payload_length,
1644 				hdr->datasn, checksum, data_crc);
1645 			data_crc_failed = 1;
1646 		} else {
1647 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1648 				" %u bytes of Data Out\n", checksum,
1649 				payload_length);
1650 		}
1651 	}
1652 
1653 	return data_crc_failed;
1654 }
1655 
1656 int
iscsit_check_dataout_payload(struct iscsit_cmd * cmd,struct iscsi_data * hdr,bool data_crc_failed)1657 iscsit_check_dataout_payload(struct iscsit_cmd *cmd, struct iscsi_data *hdr,
1658 			     bool data_crc_failed)
1659 {
1660 	struct iscsit_conn *conn = cmd->conn;
1661 	int rc, ooo_cmdsn;
1662 	/*
1663 	 * Increment post receive data and CRC values or perform
1664 	 * within-command recovery.
1665 	 */
1666 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1667 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1668 		return 0;
1669 	else if (rc == DATAOUT_SEND_R2T) {
1670 		iscsit_set_dataout_sequence_values(cmd);
1671 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1672 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1673 		/*
1674 		 * Handle extra special case for out of order
1675 		 * Unsolicited Data Out.
1676 		 */
1677 		spin_lock_bh(&cmd->istate_lock);
1678 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1679 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1680 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1681 		spin_unlock_bh(&cmd->istate_lock);
1682 
1683 		iscsit_stop_dataout_timer(cmd);
1684 		if (ooo_cmdsn)
1685 			return 0;
1686 		target_execute_cmd(&cmd->se_cmd);
1687 		return 0;
1688 	} else /* DATAOUT_CANNOT_RECOVER */
1689 		return -1;
1690 
1691 	return 0;
1692 }
1693 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1694 
iscsit_handle_data_out(struct iscsit_conn * conn,unsigned char * buf)1695 static int iscsit_handle_data_out(struct iscsit_conn *conn, unsigned char *buf)
1696 {
1697 	struct iscsit_cmd *cmd = NULL;
1698 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1699 	int rc;
1700 	bool data_crc_failed = false;
1701 
1702 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1703 	if (rc < 0)
1704 		return 0;
1705 	else if (!cmd)
1706 		return 0;
1707 
1708 	rc = iscsit_get_dataout(conn, cmd, hdr);
1709 	if (rc < 0)
1710 		return rc;
1711 	else if (rc > 0)
1712 		data_crc_failed = true;
1713 
1714 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1715 }
1716 
iscsit_setup_nop_out(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_nopout * hdr)1717 int iscsit_setup_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1718 			 struct iscsi_nopout *hdr)
1719 {
1720 	u32 payload_length = ntoh24(hdr->dlength);
1721 
1722 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1723 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1724 		if (!cmd)
1725 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1726 						 (unsigned char *)hdr);
1727 
1728 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1729 					 (unsigned char *)hdr);
1730 	}
1731 
1732 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1733 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1734 			" not set, protocol error.\n");
1735 		if (!cmd)
1736 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1737 						 (unsigned char *)hdr);
1738 
1739 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1740 					 (unsigned char *)hdr);
1741 	}
1742 
1743 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1744 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1745 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1746 			" error.\n", payload_length,
1747 			conn->conn_ops->MaxXmitDataSegmentLength);
1748 		if (!cmd)
1749 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1750 						 (unsigned char *)hdr);
1751 
1752 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1753 					 (unsigned char *)hdr);
1754 	}
1755 
1756 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1757 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1758 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1759 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1760 		payload_length);
1761 	/*
1762 	 * This is not a response to a Unsolicited NopIN, which means
1763 	 * it can either be a NOPOUT ping request (with a valid ITT),
1764 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1765 	 * Either way, make sure we allocate an struct iscsit_cmd, as both
1766 	 * can contain ping data.
1767 	 */
1768 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1769 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1770 		cmd->i_state		= ISTATE_SEND_NOPIN;
1771 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1772 						1 : 0);
1773 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1774 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1775 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1776 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1777 		cmd->data_direction	= DMA_NONE;
1778 	}
1779 
1780 	return 0;
1781 }
1782 EXPORT_SYMBOL(iscsit_setup_nop_out);
1783 
iscsit_process_nop_out(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_nopout * hdr)1784 int iscsit_process_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1785 			   struct iscsi_nopout *hdr)
1786 {
1787 	struct iscsit_cmd *cmd_p = NULL;
1788 	int cmdsn_ret = 0;
1789 	/*
1790 	 * Initiator is expecting a NopIN ping reply..
1791 	 */
1792 	if (hdr->itt != RESERVED_ITT) {
1793 		if (!cmd)
1794 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1795 						(unsigned char *)hdr);
1796 
1797 		spin_lock_bh(&conn->cmd_lock);
1798 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1799 		spin_unlock_bh(&conn->cmd_lock);
1800 
1801 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1802 
1803 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1804 			iscsit_add_cmd_to_response_queue(cmd, conn,
1805 							 cmd->i_state);
1806 			return 0;
1807 		}
1808 
1809 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1810 				(unsigned char *)hdr, hdr->cmdsn);
1811                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1812 			return 0;
1813 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1814 			return -1;
1815 
1816 		return 0;
1817 	}
1818 	/*
1819 	 * This was a response to a unsolicited NOPIN ping.
1820 	 */
1821 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1822 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1823 		if (!cmd_p)
1824 			return -EINVAL;
1825 
1826 		iscsit_stop_nopin_response_timer(conn);
1827 
1828 		cmd_p->i_state = ISTATE_REMOVE;
1829 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1830 
1831 		iscsit_start_nopin_timer(conn);
1832 		return 0;
1833 	}
1834 	/*
1835 	 * Otherwise, initiator is not expecting a NOPIN is response.
1836 	 * Just ignore for now.
1837 	 */
1838 
1839 	if (cmd)
1840 		iscsit_free_cmd(cmd, false);
1841 
1842         return 0;
1843 }
1844 EXPORT_SYMBOL(iscsit_process_nop_out);
1845 
iscsit_handle_nop_out(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)1846 static int iscsit_handle_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1847 				 unsigned char *buf)
1848 {
1849 	unsigned char *ping_data = NULL;
1850 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1851 	struct kvec *iov = NULL;
1852 	u32 payload_length = ntoh24(hdr->dlength);
1853 	int ret;
1854 
1855 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1856 	if (ret < 0)
1857 		return 0;
1858 	/*
1859 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1860 	 */
1861 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1862 		u32 checksum, data_crc, padding = 0;
1863 		int niov = 0, rx_got, rx_size = payload_length;
1864 
1865 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1866 		if (!ping_data) {
1867 			ret = -1;
1868 			goto out;
1869 		}
1870 
1871 		iov = &cmd->iov_misc[0];
1872 		iov[niov].iov_base	= ping_data;
1873 		iov[niov++].iov_len	= payload_length;
1874 
1875 		padding = ((-payload_length) & 3);
1876 		if (padding != 0) {
1877 			pr_debug("Receiving %u additional bytes"
1878 				" for padding.\n", padding);
1879 			iov[niov].iov_base	= &cmd->pad_bytes;
1880 			iov[niov++].iov_len	= padding;
1881 			rx_size += padding;
1882 		}
1883 		if (conn->conn_ops->DataDigest) {
1884 			iov[niov].iov_base	= &checksum;
1885 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1886 			rx_size += ISCSI_CRC_LEN;
1887 		}
1888 
1889 		WARN_ON_ONCE(niov > ARRAY_SIZE(cmd->iov_misc));
1890 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1891 		if (rx_got != rx_size) {
1892 			ret = -1;
1893 			goto out;
1894 		}
1895 
1896 		if (conn->conn_ops->DataDigest) {
1897 			data_crc = iscsit_crc_buf(ping_data, payload_length,
1898 						  padding, cmd->pad_bytes);
1899 			if (checksum != data_crc) {
1900 				pr_err("Ping data CRC32C DataDigest"
1901 				" 0x%08x does not match computed 0x%08x\n",
1902 					checksum, data_crc);
1903 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1904 					pr_err("Unable to recover from"
1905 					" NOPOUT Ping DataCRC failure while in"
1906 						" ERL=0.\n");
1907 					ret = -1;
1908 					goto out;
1909 				} else {
1910 					/*
1911 					 * Silently drop this PDU and let the
1912 					 * initiator plug the CmdSN gap.
1913 					 */
1914 					pr_debug("Dropping NOPOUT"
1915 					" Command CmdSN: 0x%08x due to"
1916 					" DataCRC error.\n", hdr->cmdsn);
1917 					ret = 0;
1918 					goto out;
1919 				}
1920 			} else {
1921 				pr_debug("Got CRC32C DataDigest"
1922 				" 0x%08x for %u bytes of ping data.\n",
1923 					checksum, payload_length);
1924 			}
1925 		}
1926 
1927 		ping_data[payload_length] = '\0';
1928 		/*
1929 		 * Attach ping data to struct iscsit_cmd->buf_ptr.
1930 		 */
1931 		cmd->buf_ptr = ping_data;
1932 		cmd->buf_ptr_size = payload_length;
1933 
1934 		pr_debug("Got %u bytes of NOPOUT ping"
1935 			" data.\n", payload_length);
1936 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1937 	}
1938 
1939 	return iscsit_process_nop_out(conn, cmd, hdr);
1940 out:
1941 	if (cmd)
1942 		iscsit_free_cmd(cmd, false);
1943 
1944 	kfree(ping_data);
1945 	return ret;
1946 }
1947 
iscsit_convert_tmf(u8 iscsi_tmf)1948 static enum tcm_tmreq_table iscsit_convert_tmf(u8 iscsi_tmf)
1949 {
1950 	switch (iscsi_tmf) {
1951 	case ISCSI_TM_FUNC_ABORT_TASK:
1952 		return TMR_ABORT_TASK;
1953 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1954 		return TMR_ABORT_TASK_SET;
1955 	case ISCSI_TM_FUNC_CLEAR_ACA:
1956 		return TMR_CLEAR_ACA;
1957 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1958 		return TMR_CLEAR_TASK_SET;
1959 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1960 		return TMR_LUN_RESET;
1961 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1962 		return TMR_TARGET_WARM_RESET;
1963 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1964 		return TMR_TARGET_COLD_RESET;
1965 	default:
1966 		return TMR_UNKNOWN;
1967 	}
1968 }
1969 
1970 int
iscsit_handle_task_mgt_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)1971 iscsit_handle_task_mgt_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1972 			   unsigned char *buf)
1973 {
1974 	struct se_tmr_req *se_tmr;
1975 	struct iscsi_tmr_req *tmr_req;
1976 	struct iscsi_tm *hdr;
1977 	int out_of_order_cmdsn = 0, ret;
1978 	u8 function, tcm_function = TMR_UNKNOWN;
1979 
1980 	hdr			= (struct iscsi_tm *) buf;
1981 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1982 	function = hdr->flags;
1983 
1984 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1985 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1986 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1987 		hdr->rtt, hdr->refcmdsn, conn->cid);
1988 
1989 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1990 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1991 	     hdr->rtt != RESERVED_ITT)) {
1992 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1993 		hdr->rtt = RESERVED_ITT;
1994 	}
1995 
1996 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1997 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1998 		pr_err("Task Management Request TASK_REASSIGN not"
1999 			" issued as immediate command, bad iSCSI Initiator"
2000 				"implementation\n");
2001 		return iscsit_add_reject_cmd(cmd,
2002 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
2003 	}
2004 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
2005 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
2006 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
2007 
2008 	cmd->data_direction = DMA_NONE;
2009 	cmd->tmr_req = kzalloc_obj(*cmd->tmr_req);
2010 	if (!cmd->tmr_req) {
2011 		return iscsit_add_reject_cmd(cmd,
2012 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
2013 					     buf);
2014 	}
2015 
2016 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
2017 			  conn->sess->se_sess, 0, DMA_NONE,
2018 			  TCM_SIMPLE_TAG, cmd->sense_buffer + 2,
2019 			  scsilun_to_int(&hdr->lun),
2020 			  conn->cmd_cnt);
2021 
2022 	target_get_sess_cmd(&cmd->se_cmd, true);
2023 
2024 	/*
2025 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
2026 	 * LIO-Target $FABRIC_MOD
2027 	 */
2028 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2029 		tcm_function = iscsit_convert_tmf(function);
2030 		if (tcm_function == TMR_UNKNOWN) {
2031 			pr_err("Unknown iSCSI TMR Function:"
2032 			       " 0x%02x\n", function);
2033 			return iscsit_add_reject_cmd(cmd,
2034 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2035 		}
2036 	}
2037 	ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
2038 				 GFP_KERNEL);
2039 	if (ret < 0)
2040 		return iscsit_add_reject_cmd(cmd,
2041 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2042 
2043 	cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2044 
2045 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2046 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2047 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2048 	cmd->init_task_tag	= hdr->itt;
2049 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2050 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2051 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2052 	se_tmr			= cmd->se_cmd.se_tmr_req;
2053 	tmr_req			= cmd->tmr_req;
2054 	/*
2055 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2056 	 */
2057 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2058 		ret = transport_lookup_tmr_lun(&cmd->se_cmd);
2059 		if (ret < 0) {
2060 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2061 			goto attach;
2062 		}
2063 	}
2064 
2065 	switch (function) {
2066 	case ISCSI_TM_FUNC_ABORT_TASK:
2067 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2068 		if (se_tmr->response)
2069 			goto attach;
2070 		break;
2071 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2072 	case ISCSI_TM_FUNC_CLEAR_ACA:
2073 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2074 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2075 		break;
2076 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2077 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2078 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2079 			goto attach;
2080 		}
2081 		break;
2082 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2083 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2084 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2085 			goto attach;
2086 		}
2087 		break;
2088 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2089 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2090 		/*
2091 		 * Perform sanity checks on the ExpDataSN only if the
2092 		 * TASK_REASSIGN was successful.
2093 		 */
2094 		if (se_tmr->response)
2095 			break;
2096 
2097 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2098 			return iscsit_add_reject_cmd(cmd,
2099 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2100 		break;
2101 	default:
2102 		pr_err("Unknown TMR function: 0x%02x, protocol"
2103 			" error.\n", function);
2104 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2105 		goto attach;
2106 	}
2107 
2108 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2109 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2110 		se_tmr->call_transport = 1;
2111 attach:
2112 	spin_lock_bh(&conn->cmd_lock);
2113 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2114 	spin_unlock_bh(&conn->cmd_lock);
2115 
2116 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2117 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2118 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP) {
2119 			out_of_order_cmdsn = 1;
2120 		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2121 			target_put_sess_cmd(&cmd->se_cmd);
2122 			return 0;
2123 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2124 			return -1;
2125 		}
2126 	}
2127 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2128 
2129 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2130 		return 0;
2131 	/*
2132 	 * Found the referenced task, send to transport for processing.
2133 	 */
2134 	if (se_tmr->call_transport)
2135 		return transport_generic_handle_tmr(&cmd->se_cmd);
2136 
2137 	/*
2138 	 * Could not find the referenced LUN, task, or Task Management
2139 	 * command not authorized or supported.  Change state and
2140 	 * let the tx_thread send the response.
2141 	 *
2142 	 * For connection recovery, this is also the default action for
2143 	 * TMR TASK_REASSIGN.
2144 	 */
2145 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2146 	target_put_sess_cmd(&cmd->se_cmd);
2147 	return 0;
2148 }
2149 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2150 
2151 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2152 int
iscsit_setup_text_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_text * hdr)2153 iscsit_setup_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2154 		      struct iscsi_text *hdr)
2155 {
2156 	u32 payload_length = ntoh24(hdr->dlength);
2157 
2158 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2159 		pr_err("Unable to accept text parameter length: %u"
2160 			"greater than MaxXmitDataSegmentLength %u.\n",
2161 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2162 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2163 					 (unsigned char *)hdr);
2164 	}
2165 
2166 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2167 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2168 		pr_err("Multi sequence text commands currently not supported\n");
2169 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2170 					(unsigned char *)hdr);
2171 	}
2172 
2173 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2174 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2175 		hdr->exp_statsn, payload_length);
2176 
2177 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2178 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2179 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2180 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2181 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2182 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2183 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2184 	cmd->data_direction	= DMA_NONE;
2185 	kfree(cmd->text_in_ptr);
2186 	cmd->text_in_ptr	= NULL;
2187 
2188 	return 0;
2189 }
2190 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2191 
2192 int
iscsit_process_text_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_text * hdr)2193 iscsit_process_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2194 			struct iscsi_text *hdr)
2195 {
2196 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2197 	int cmdsn_ret;
2198 
2199 	if (!text_in) {
2200 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2201 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2202 			pr_err("Unable to locate text_in buffer for sendtargets"
2203 			       " discovery\n");
2204 			goto reject;
2205 		}
2206 		goto empty_sendtargets;
2207 	}
2208 	if (strncmp("SendTargets=", text_in, 12) != 0) {
2209 		pr_err("Received Text Data that is not"
2210 			" SendTargets, cannot continue.\n");
2211 		goto reject;
2212 	}
2213 	/* '=' confirmed in strncmp */
2214 	text_ptr = strchr(text_in, '=');
2215 	BUG_ON(!text_ptr);
2216 	if (!strncmp("=All", text_ptr, 5)) {
2217 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2218 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2219 		   !strncmp("=eui.", text_ptr, 5)) {
2220 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2221 	} else {
2222 		pr_err("Unable to locate valid SendTargets%s value\n",
2223 		       text_ptr);
2224 		goto reject;
2225 	}
2226 
2227 	spin_lock_bh(&conn->cmd_lock);
2228 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2229 	spin_unlock_bh(&conn->cmd_lock);
2230 
2231 empty_sendtargets:
2232 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2233 
2234 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2235 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2236 				(unsigned char *)hdr, hdr->cmdsn);
2237 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2238 			return -1;
2239 
2240 		return 0;
2241 	}
2242 
2243 	return iscsit_execute_cmd(cmd, 0);
2244 
2245 reject:
2246 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2247 				 (unsigned char *)hdr);
2248 }
2249 EXPORT_SYMBOL(iscsit_process_text_cmd);
2250 
2251 static int
iscsit_handle_text_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)2252 iscsit_handle_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2253 		       unsigned char *buf)
2254 {
2255 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2256 	char *text_in = NULL;
2257 	u32 payload_length = ntoh24(hdr->dlength);
2258 	int rx_size, rc;
2259 
2260 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2261 	if (rc < 0)
2262 		return 0;
2263 
2264 	rx_size = payload_length;
2265 	if (payload_length) {
2266 		u32 checksum = 0, data_crc = 0;
2267 		u32 padding = 0;
2268 		int niov = 0, rx_got;
2269 		struct kvec iov[2];
2270 
2271 		rx_size = ALIGN(payload_length, 4);
2272 		text_in = kzalloc(rx_size, GFP_KERNEL);
2273 		if (!text_in)
2274 			goto reject;
2275 
2276 		cmd->text_in_ptr = text_in;
2277 
2278 		memset(iov, 0, sizeof(iov));
2279 		iov[niov].iov_base	= text_in;
2280 		iov[niov++].iov_len	= rx_size;
2281 
2282 		padding = rx_size - payload_length;
2283 		if (padding)
2284 			pr_debug("Receiving %u additional bytes"
2285 					" for padding.\n", padding);
2286 		if (conn->conn_ops->DataDigest) {
2287 			iov[niov].iov_base	= &checksum;
2288 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2289 			rx_size += ISCSI_CRC_LEN;
2290 		}
2291 
2292 		WARN_ON_ONCE(niov > ARRAY_SIZE(iov));
2293 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2294 		if (rx_got != rx_size)
2295 			goto reject;
2296 
2297 		if (conn->conn_ops->DataDigest) {
2298 			data_crc = iscsit_crc_buf(text_in,
2299 						  ALIGN(payload_length, 4),
2300 						  0, NULL);
2301 			if (checksum != data_crc) {
2302 				pr_err("Text data CRC32C DataDigest"
2303 					" 0x%08x does not match computed"
2304 					" 0x%08x\n", checksum, data_crc);
2305 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2306 					pr_err("Unable to recover from"
2307 					" Text Data digest failure while in"
2308 						" ERL=0.\n");
2309 					goto reject;
2310 				} else {
2311 					/*
2312 					 * Silently drop this PDU and let the
2313 					 * initiator plug the CmdSN gap.
2314 					 */
2315 					pr_debug("Dropping Text"
2316 					" Command CmdSN: 0x%08x due to"
2317 					" DataCRC error.\n", hdr->cmdsn);
2318 					kfree(text_in);
2319 					cmd->text_in_ptr = NULL;
2320 					return 0;
2321 				}
2322 			} else {
2323 				pr_debug("Got CRC32C DataDigest"
2324 					" 0x%08x for %u bytes of text data.\n",
2325 						checksum, payload_length);
2326 			}
2327 		}
2328 		text_in[payload_length - 1] = '\0';
2329 		pr_debug("Successfully read %d bytes of text"
2330 				" data.\n", payload_length);
2331 	}
2332 
2333 	return iscsit_process_text_cmd(conn, cmd, hdr);
2334 
2335 reject:
2336 	kfree(cmd->text_in_ptr);
2337 	cmd->text_in_ptr = NULL;
2338 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2339 }
2340 
iscsit_logout_closesession(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2341 int iscsit_logout_closesession(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2342 {
2343 	struct iscsit_conn *conn_p;
2344 	struct iscsit_session *sess = conn->sess;
2345 
2346 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2347 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2348 
2349 	atomic_set(&sess->session_logout, 1);
2350 	atomic_set(&conn->conn_logout_remove, 1);
2351 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2352 
2353 	iscsit_inc_conn_usage_count(conn);
2354 	iscsit_inc_session_usage_count(sess);
2355 
2356 	spin_lock_bh(&sess->conn_lock);
2357 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2358 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2359 			continue;
2360 
2361 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2362 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2363 	}
2364 	spin_unlock_bh(&sess->conn_lock);
2365 
2366 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2367 
2368 	return 0;
2369 }
2370 
iscsit_logout_closeconnection(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2371 int iscsit_logout_closeconnection(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2372 {
2373 	struct iscsit_conn *l_conn;
2374 	struct iscsit_session *sess = conn->sess;
2375 
2376 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2377 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2378 
2379 	/*
2380 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2381 	 * can arrive on a connection with a differing CID.
2382 	 */
2383 	if (conn->cid == cmd->logout_cid) {
2384 		spin_lock_bh(&conn->state_lock);
2385 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2386 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2387 
2388 		atomic_set(&conn->conn_logout_remove, 1);
2389 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2390 		iscsit_inc_conn_usage_count(conn);
2391 
2392 		spin_unlock_bh(&conn->state_lock);
2393 	} else {
2394 		/*
2395 		 * Handle all different cid CLOSECONNECTION requests in
2396 		 * iscsit_logout_post_handler_diffcid() as to give enough
2397 		 * time for any non immediate command's CmdSN to be
2398 		 * acknowledged on the connection in question.
2399 		 *
2400 		 * Here we simply make sure the CID is still around.
2401 		 */
2402 		l_conn = iscsit_get_conn_from_cid(sess,
2403 				cmd->logout_cid);
2404 		if (!l_conn) {
2405 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2406 			iscsit_add_cmd_to_response_queue(cmd, conn,
2407 					cmd->i_state);
2408 			return 0;
2409 		}
2410 
2411 		iscsit_dec_conn_usage_count(l_conn);
2412 	}
2413 
2414 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2415 
2416 	return 0;
2417 }
2418 
iscsit_logout_removeconnforrecovery(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2419 int iscsit_logout_removeconnforrecovery(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2420 {
2421 	struct iscsit_session *sess = conn->sess;
2422 
2423 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2424 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2425 
2426 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2427 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2428 			" while ERL!=2.\n");
2429 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2430 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2431 		return 0;
2432 	}
2433 
2434 	if (conn->cid == cmd->logout_cid) {
2435 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2436 			" with CID: %hu on CID: %hu, implementation error.\n",
2437 				cmd->logout_cid, conn->cid);
2438 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2439 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2440 		return 0;
2441 	}
2442 
2443 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2444 
2445 	return 0;
2446 }
2447 
2448 int
iscsit_handle_logout_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)2449 iscsit_handle_logout_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2450 			unsigned char *buf)
2451 {
2452 	int cmdsn_ret, logout_remove = 0;
2453 	u8 reason_code = 0;
2454 	struct iscsi_logout *hdr;
2455 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2456 
2457 	hdr			= (struct iscsi_logout *) buf;
2458 	reason_code		= (hdr->flags & 0x7f);
2459 
2460 	if (tiqn) {
2461 		spin_lock(&tiqn->logout_stats.lock);
2462 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2463 			tiqn->logout_stats.normal_logouts++;
2464 		else
2465 			tiqn->logout_stats.abnormal_logouts++;
2466 		spin_unlock(&tiqn->logout_stats.lock);
2467 	}
2468 
2469 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2470 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2471 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2472 		hdr->cid, conn->cid);
2473 
2474 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2475 		pr_err("Received logout request on connection that"
2476 			" is not in logged in state, ignoring request.\n");
2477 		iscsit_free_cmd(cmd, false);
2478 		return 0;
2479 	}
2480 
2481 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2482 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2483 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2484 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2485 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2486 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2487 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2488 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2489 	cmd->logout_reason      = reason_code;
2490 	cmd->data_direction     = DMA_NONE;
2491 
2492 	/*
2493 	 * We need to sleep in these cases (by returning 1) until the Logout
2494 	 * Response gets sent in the tx thread.
2495 	 */
2496 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2497 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2498 	    be16_to_cpu(hdr->cid) == conn->cid))
2499 		logout_remove = 1;
2500 
2501 	spin_lock_bh(&conn->cmd_lock);
2502 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2503 	spin_unlock_bh(&conn->cmd_lock);
2504 
2505 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2506 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2507 
2508 	/*
2509 	 * Immediate commands are executed, well, immediately.
2510 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2511 	 */
2512 	if (cmd->immediate_cmd) {
2513 		int ret = iscsit_execute_cmd(cmd, 0);
2514 
2515 		if (ret < 0)
2516 			return ret;
2517 	} else {
2518 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2519 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2520 			logout_remove = 0;
2521 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2522 			return -1;
2523 	}
2524 
2525 	return logout_remove;
2526 }
2527 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2528 
iscsit_handle_snack(struct iscsit_conn * conn,unsigned char * buf)2529 int iscsit_handle_snack(
2530 	struct iscsit_conn *conn,
2531 	unsigned char *buf)
2532 {
2533 	struct iscsi_snack *hdr;
2534 
2535 	hdr			= (struct iscsi_snack *) buf;
2536 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2537 
2538 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2539 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2540 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2541 			hdr->begrun, hdr->runlength, conn->cid);
2542 
2543 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2544 		pr_err("Initiator sent SNACK request while in"
2545 			" ErrorRecoveryLevel=0.\n");
2546 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2547 					 buf);
2548 	}
2549 	/*
2550 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2551 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2552 	 */
2553 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2554 	case 0:
2555 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2556 			hdr->itt,
2557 			be32_to_cpu(hdr->ttt),
2558 			be32_to_cpu(hdr->begrun),
2559 			be32_to_cpu(hdr->runlength));
2560 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2561 		return iscsit_handle_status_snack(conn, hdr->itt,
2562 			be32_to_cpu(hdr->ttt),
2563 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2564 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2565 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2566 			be32_to_cpu(hdr->begrun),
2567 			be32_to_cpu(hdr->runlength));
2568 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2569 		/* FIXME: Support R-Data SNACK */
2570 		pr_err("R-Data SNACK Not Supported.\n");
2571 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2572 					 buf);
2573 	default:
2574 		pr_err("Unknown SNACK type 0x%02x, protocol"
2575 			" error.\n", hdr->flags & 0x0f);
2576 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2577 					 buf);
2578 	}
2579 
2580 	return 0;
2581 }
2582 EXPORT_SYMBOL(iscsit_handle_snack);
2583 
iscsit_rx_thread_wait_for_tcp(struct iscsit_conn * conn)2584 static void iscsit_rx_thread_wait_for_tcp(struct iscsit_conn *conn)
2585 {
2586 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2587 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2588 		wait_for_completion_interruptible_timeout(
2589 					&conn->rx_half_close_comp,
2590 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2591 	}
2592 }
2593 
iscsit_handle_immediate_data(struct iscsit_cmd * cmd,struct iscsi_scsi_req * hdr,u32 length)2594 static int iscsit_handle_immediate_data(
2595 	struct iscsit_cmd *cmd,
2596 	struct iscsi_scsi_req *hdr,
2597 	u32 length)
2598 {
2599 	int iov_ret, rx_got = 0, rx_size = 0;
2600 	u32 checksum, iov_count = 0, padding = 0;
2601 	struct iscsit_conn *conn = cmd->conn;
2602 	struct kvec *iov;
2603 	void *overflow_buf = NULL;
2604 
2605 	BUG_ON(cmd->write_data_done > cmd->se_cmd.data_length);
2606 	rx_size = min(cmd->se_cmd.data_length - cmd->write_data_done, length);
2607 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data,
2608 				   cmd->orig_iov_data_count - 2,
2609 				   cmd->write_data_done, rx_size);
2610 	if (iov_ret < 0)
2611 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2612 
2613 	iov_count = iov_ret;
2614 	iov = &cmd->iov_data[0];
2615 	if (rx_size < length) {
2616 		/*
2617 		 * Special case: length of immediate data exceeds the data
2618 		 * buffer size derived from the CDB.
2619 		 */
2620 		overflow_buf = kmalloc(length - rx_size, GFP_KERNEL);
2621 		if (!overflow_buf) {
2622 			iscsit_unmap_iovec(cmd);
2623 			return IMMEDIATE_DATA_CANNOT_RECOVER;
2624 		}
2625 		cmd->overflow_buf = overflow_buf;
2626 		iov[iov_count].iov_base = overflow_buf;
2627 		iov[iov_count].iov_len = length - rx_size;
2628 		iov_count++;
2629 		rx_size = length;
2630 	}
2631 
2632 	padding = ((-length) & 3);
2633 	if (padding != 0) {
2634 		iov[iov_count].iov_base	= cmd->pad_bytes;
2635 		iov[iov_count++].iov_len = padding;
2636 		rx_size += padding;
2637 	}
2638 
2639 	if (conn->conn_ops->DataDigest) {
2640 		iov[iov_count].iov_base		= &checksum;
2641 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2642 		rx_size += ISCSI_CRC_LEN;
2643 	}
2644 
2645 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
2646 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2647 
2648 	iscsit_unmap_iovec(cmd);
2649 
2650 	if (rx_got != rx_size) {
2651 		iscsit_rx_thread_wait_for_tcp(conn);
2652 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2653 	}
2654 
2655 	if (conn->conn_ops->DataDigest) {
2656 		u32 data_crc;
2657 
2658 		data_crc = iscsit_crc_sglist(cmd, length, padding,
2659 					     cmd->pad_bytes);
2660 		if (checksum != data_crc) {
2661 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2662 				" does not match computed 0x%08x\n", checksum,
2663 				data_crc);
2664 
2665 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2666 				pr_err("Unable to recover from"
2667 					" Immediate Data digest failure while"
2668 					" in ERL=0.\n");
2669 				iscsit_reject_cmd(cmd,
2670 						ISCSI_REASON_DATA_DIGEST_ERROR,
2671 						(unsigned char *)hdr);
2672 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2673 			} else {
2674 				iscsit_reject_cmd(cmd,
2675 						ISCSI_REASON_DATA_DIGEST_ERROR,
2676 						(unsigned char *)hdr);
2677 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2678 			}
2679 		} else {
2680 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2681 				" %u bytes of Immediate Data\n", checksum,
2682 				length);
2683 		}
2684 	}
2685 
2686 	cmd->write_data_done += length;
2687 
2688 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2689 		spin_lock_bh(&cmd->istate_lock);
2690 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2691 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2692 		spin_unlock_bh(&cmd->istate_lock);
2693 	}
2694 
2695 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2696 }
2697 
2698 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2699 	with active network interface */
iscsit_build_conn_drop_async_message(struct iscsit_conn * conn)2700 static void iscsit_build_conn_drop_async_message(struct iscsit_conn *conn)
2701 {
2702 	struct iscsit_cmd *cmd;
2703 	struct iscsit_conn *conn_p;
2704 	bool found = false;
2705 
2706 	lockdep_assert_held(&conn->sess->conn_lock);
2707 
2708 	/*
2709 	 * Only send a Asynchronous Message on connections whos network
2710 	 * interface is still functional.
2711 	 */
2712 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2713 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2714 			iscsit_inc_conn_usage_count(conn_p);
2715 			found = true;
2716 			break;
2717 		}
2718 	}
2719 
2720 	if (!found)
2721 		return;
2722 
2723 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2724 	if (!cmd) {
2725 		iscsit_dec_conn_usage_count(conn_p);
2726 		return;
2727 	}
2728 
2729 	cmd->logout_cid = conn->cid;
2730 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2731 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2732 
2733 	spin_lock_bh(&conn_p->cmd_lock);
2734 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2735 	spin_unlock_bh(&conn_p->cmd_lock);
2736 
2737 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2738 	iscsit_dec_conn_usage_count(conn_p);
2739 }
2740 
iscsit_send_conn_drop_async_message(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2741 static int iscsit_send_conn_drop_async_message(
2742 	struct iscsit_cmd *cmd,
2743 	struct iscsit_conn *conn)
2744 {
2745 	struct iscsi_async *hdr;
2746 
2747 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2748 
2749 	hdr			= (struct iscsi_async *) cmd->pdu;
2750 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2751 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2752 	cmd->init_task_tag	= RESERVED_ITT;
2753 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2754 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2755 	cmd->stat_sn		= conn->stat_sn++;
2756 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2757 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2758 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2759 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2760 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2761 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2762 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2763 
2764 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2765 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2766 			cmd->logout_cid, conn->cid);
2767 
2768 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2769 }
2770 
iscsit_tx_thread_wait_for_tcp(struct iscsit_conn * conn)2771 static void iscsit_tx_thread_wait_for_tcp(struct iscsit_conn *conn)
2772 {
2773 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2774 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2775 		wait_for_completion_interruptible_timeout(
2776 					&conn->tx_half_close_comp,
2777 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2778 	}
2779 }
2780 
2781 void
iscsit_build_datain_pdu(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_datain * datain,struct iscsi_data_rsp * hdr,bool set_statsn)2782 iscsit_build_datain_pdu(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2783 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2784 			bool set_statsn)
2785 {
2786 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2787 	hdr->flags		= datain->flags;
2788 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2789 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2790 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2791 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2792 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2793 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2794 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2795 		}
2796 	}
2797 	hton24(hdr->dlength, datain->length);
2798 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2799 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2800 				(struct scsi_lun *)&hdr->lun);
2801 	else
2802 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2803 
2804 	hdr->itt		= cmd->init_task_tag;
2805 
2806 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2807 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2808 	else
2809 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2810 	if (set_statsn)
2811 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2812 	else
2813 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2814 
2815 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2816 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2817 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2818 	hdr->offset		= cpu_to_be32(datain->offset);
2819 
2820 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2821 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2822 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2823 		ntohl(hdr->offset), datain->length, conn->cid);
2824 }
2825 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2826 
iscsit_send_datain(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2827 static int iscsit_send_datain(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2828 {
2829 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2830 	struct iscsi_datain datain;
2831 	struct iscsi_datain_req *dr;
2832 	int eodr = 0, ret;
2833 	bool set_statsn = false;
2834 
2835 	memset(&datain, 0, sizeof(struct iscsi_datain));
2836 	dr = iscsit_get_datain_values(cmd, &datain);
2837 	if (!dr) {
2838 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2839 				cmd->init_task_tag);
2840 		return -1;
2841 	}
2842 	/*
2843 	 * Be paranoid and double check the logic for now.
2844 	 */
2845 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2846 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2847 			" datain.length: %u exceeds cmd->data_length: %u\n",
2848 			cmd->init_task_tag, datain.offset, datain.length,
2849 			cmd->se_cmd.data_length);
2850 		return -1;
2851 	}
2852 
2853 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2854 	/*
2855 	 * Special case for successfully execution w/ both DATAIN
2856 	 * and Sense Data.
2857 	 */
2858 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2859 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2860 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2861 	else {
2862 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2863 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2864 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2865 			cmd->stat_sn = conn->stat_sn++;
2866 			set_statsn = true;
2867 		} else if (dr->dr_complete ==
2868 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2869 			set_statsn = true;
2870 	}
2871 
2872 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2873 
2874 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2875 	if (ret < 0)
2876 		return ret;
2877 
2878 	if (dr->dr_complete) {
2879 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2880 				2 : 1;
2881 		iscsit_free_datain_req(cmd, dr);
2882 	}
2883 
2884 	return eodr;
2885 }
2886 
2887 int
iscsit_build_logout_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_logout_rsp * hdr)2888 iscsit_build_logout_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2889 			struct iscsi_logout_rsp *hdr)
2890 {
2891 	struct iscsit_conn *logout_conn = NULL;
2892 	struct iscsi_conn_recovery *cr = NULL;
2893 	struct iscsit_session *sess = conn->sess;
2894 	/*
2895 	 * The actual shutting down of Sessions and/or Connections
2896 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2897 	 * is done in scsi_logout_post_handler().
2898 	 */
2899 	switch (cmd->logout_reason) {
2900 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2901 		pr_debug("iSCSI session logout successful, setting"
2902 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2903 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2904 		break;
2905 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2906 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2907 			break;
2908 		/*
2909 		 * For CLOSECONNECTION logout requests carrying
2910 		 * a matching logout CID -> local CID, the reference
2911 		 * for the local CID will have been incremented in
2912 		 * iscsi_logout_closeconnection().
2913 		 *
2914 		 * For CLOSECONNECTION logout requests carrying
2915 		 * a different CID than the connection it arrived
2916 		 * on, the connection responding to cmd->logout_cid
2917 		 * is stopped in iscsit_logout_post_handler_diffcid().
2918 		 */
2919 
2920 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2921 			" successful.\n", cmd->logout_cid, conn->cid);
2922 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2923 		break;
2924 	case ISCSI_LOGOUT_REASON_RECOVERY:
2925 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2926 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2927 			break;
2928 		/*
2929 		 * If the connection is still active from our point of view
2930 		 * force connection recovery to occur.
2931 		 */
2932 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2933 				cmd->logout_cid);
2934 		if (logout_conn) {
2935 			iscsit_connection_reinstatement_rcfr(logout_conn);
2936 			iscsit_dec_conn_usage_count(logout_conn);
2937 		}
2938 
2939 		cr = iscsit_get_inactive_connection_recovery_entry(
2940 				conn->sess, cmd->logout_cid);
2941 		if (!cr) {
2942 			pr_err("Unable to locate CID: %hu for"
2943 			" REMOVECONNFORRECOVERY Logout Request.\n",
2944 				cmd->logout_cid);
2945 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2946 			break;
2947 		}
2948 
2949 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2950 
2951 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2952 			" for recovery for CID: %hu on CID: %hu successful.\n",
2953 				cmd->logout_cid, conn->cid);
2954 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2955 		break;
2956 	default:
2957 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2958 				cmd->logout_reason);
2959 		return -1;
2960 	}
2961 
2962 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2963 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2964 	hdr->response		= cmd->logout_response;
2965 	hdr->itt		= cmd->init_task_tag;
2966 	cmd->stat_sn		= conn->stat_sn++;
2967 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2968 
2969 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2970 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2971 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2972 
2973 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2974 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2975 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2976 		cmd->logout_cid, conn->cid);
2977 
2978 	return 0;
2979 }
2980 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2981 
2982 static int
iscsit_send_logout(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2983 iscsit_send_logout(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2984 {
2985 	int rc;
2986 
2987 	rc = iscsit_build_logout_rsp(cmd, conn,
2988 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2989 	if (rc < 0)
2990 		return rc;
2991 
2992 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2993 }
2994 
2995 void
iscsit_build_nopin_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_nopin * hdr,bool nopout_response)2996 iscsit_build_nopin_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2997 		       struct iscsi_nopin *hdr, bool nopout_response)
2998 {
2999 	hdr->opcode		= ISCSI_OP_NOOP_IN;
3000 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3001         hton24(hdr->dlength, cmd->buf_ptr_size);
3002 	if (nopout_response)
3003 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
3004 	hdr->itt		= cmd->init_task_tag;
3005 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
3006 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
3007 				  conn->stat_sn;
3008 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3009 
3010 	if (nopout_response)
3011 		iscsit_increment_maxcmdsn(cmd, conn->sess);
3012 
3013 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3014 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3015 
3016 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
3017 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
3018 		"Solicited" : "Unsolicited", cmd->init_task_tag,
3019 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
3020 }
3021 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
3022 
3023 /*
3024  *	Unsolicited NOPIN, either requesting a response or not.
3025  */
iscsit_send_unsolicited_nopin(struct iscsit_cmd * cmd,struct iscsit_conn * conn,int want_response)3026 static int iscsit_send_unsolicited_nopin(
3027 	struct iscsit_cmd *cmd,
3028 	struct iscsit_conn *conn,
3029 	int want_response)
3030 {
3031 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3032 	int ret;
3033 
3034 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3035 
3036 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3037 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3038 
3039 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3040 	if (ret < 0)
3041 		return ret;
3042 
3043 	spin_lock_bh(&cmd->istate_lock);
3044 	cmd->i_state = want_response ?
3045 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3046 	spin_unlock_bh(&cmd->istate_lock);
3047 
3048 	return 0;
3049 }
3050 
3051 static int
iscsit_send_nopin(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3052 iscsit_send_nopin(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3053 {
3054 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3055 
3056 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3057 
3058 	/*
3059 	 * NOPOUT Ping Data is attached to struct iscsit_cmd->buf_ptr.
3060 	 * NOPOUT DataSegmentLength is at struct iscsit_cmd->buf_ptr_size.
3061 	 */
3062 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3063 
3064 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3065 						     cmd->buf_ptr,
3066 						     cmd->buf_ptr_size);
3067 }
3068 
iscsit_send_r2t(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3069 static int iscsit_send_r2t(
3070 	struct iscsit_cmd *cmd,
3071 	struct iscsit_conn *conn)
3072 {
3073 	struct iscsi_r2t *r2t;
3074 	struct iscsi_r2t_rsp *hdr;
3075 	int ret;
3076 
3077 	r2t = iscsit_get_r2t_from_list(cmd);
3078 	if (!r2t)
3079 		return -1;
3080 
3081 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3082 	memset(hdr, 0, ISCSI_HDR_LEN);
3083 	hdr->opcode		= ISCSI_OP_R2T;
3084 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3085 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3086 			(struct scsi_lun *)&hdr->lun);
3087 	hdr->itt		= cmd->init_task_tag;
3088 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3089 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3090 	else
3091 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3092 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3093 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3094 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3095 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3096 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3097 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3098 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3099 
3100 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3101 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3102 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3103 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3104 			r2t->offset, r2t->xfer_len, conn->cid);
3105 
3106 	spin_lock_bh(&cmd->r2t_lock);
3107 	r2t->sent_r2t = 1;
3108 	spin_unlock_bh(&cmd->r2t_lock);
3109 
3110 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3111 	if (ret < 0) {
3112 		return ret;
3113 	}
3114 
3115 	spin_lock_bh(&cmd->dataout_timeout_lock);
3116 	iscsit_start_dataout_timer(cmd, conn);
3117 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3118 
3119 	return 0;
3120 }
3121 
3122 /*
3123  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3124  *		connection recovery.
3125  */
iscsit_build_r2ts_for_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,bool recovery)3126 int iscsit_build_r2ts_for_cmd(
3127 	struct iscsit_conn *conn,
3128 	struct iscsit_cmd *cmd,
3129 	bool recovery)
3130 {
3131 	int first_r2t = 1;
3132 	u32 offset = 0, xfer_len = 0;
3133 
3134 	spin_lock_bh(&cmd->r2t_lock);
3135 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3136 		spin_unlock_bh(&cmd->r2t_lock);
3137 		return 0;
3138 	}
3139 
3140 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3141 	    !recovery)
3142 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3143 
3144 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3145 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3146 			offset = cmd->r2t_offset;
3147 
3148 			if (first_r2t && recovery) {
3149 				int new_data_end = offset +
3150 					conn->sess->sess_ops->MaxBurstLength -
3151 					cmd->next_burst_len;
3152 
3153 				if (new_data_end > cmd->se_cmd.data_length)
3154 					xfer_len = cmd->se_cmd.data_length - offset;
3155 				else
3156 					xfer_len =
3157 						conn->sess->sess_ops->MaxBurstLength -
3158 						cmd->next_burst_len;
3159 			} else {
3160 				int new_data_end = offset +
3161 					conn->sess->sess_ops->MaxBurstLength;
3162 
3163 				if (new_data_end > cmd->se_cmd.data_length)
3164 					xfer_len = cmd->se_cmd.data_length - offset;
3165 				else
3166 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3167 			}
3168 
3169 			if ((s32)xfer_len < 0) {
3170 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3171 				break;
3172 			}
3173 
3174 			cmd->r2t_offset += xfer_len;
3175 
3176 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3177 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3178 		} else {
3179 			struct iscsi_seq *seq;
3180 
3181 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3182 			if (!seq) {
3183 				spin_unlock_bh(&cmd->r2t_lock);
3184 				return -1;
3185 			}
3186 
3187 			offset = seq->offset;
3188 			xfer_len = seq->xfer_len;
3189 
3190 			if (cmd->seq_send_order == cmd->seq_count)
3191 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3192 		}
3193 		cmd->outstanding_r2ts++;
3194 		first_r2t = 0;
3195 
3196 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3197 			spin_unlock_bh(&cmd->r2t_lock);
3198 			return -1;
3199 		}
3200 
3201 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3202 			break;
3203 	}
3204 	spin_unlock_bh(&cmd->r2t_lock);
3205 
3206 	return 0;
3207 }
3208 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3209 
iscsit_build_rsp_pdu(struct iscsit_cmd * cmd,struct iscsit_conn * conn,bool inc_stat_sn,struct iscsi_scsi_rsp * hdr)3210 void iscsit_build_rsp_pdu(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3211 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3212 {
3213 	if (inc_stat_sn)
3214 		cmd->stat_sn = conn->stat_sn++;
3215 
3216 	atomic_long_inc(&conn->sess->rsp_pdus);
3217 
3218 	memset(hdr, 0, ISCSI_HDR_LEN);
3219 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3220 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3221 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3222 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3223 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3224 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3225 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3226 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3227 	}
3228 	hdr->response		= cmd->iscsi_response;
3229 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3230 	hdr->itt		= cmd->init_task_tag;
3231 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3232 
3233 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3234 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3235 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3236 
3237 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3238 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3239 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3240 		cmd->se_cmd.scsi_status, conn->cid);
3241 }
3242 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3243 
iscsit_send_response(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3244 static int iscsit_send_response(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3245 {
3246 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3247 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3248 	void *data_buf = NULL;
3249 	u32 padding = 0, data_buf_len = 0;
3250 
3251 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3252 
3253 	/*
3254 	 * Attach SENSE DATA payload to iSCSI Response PDU
3255 	 */
3256 	if (cmd->se_cmd.sense_buffer &&
3257 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3258 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3259 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3260 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3261 
3262 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3263 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3264 		data_buf = cmd->sense_buffer;
3265 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3266 
3267 		if (padding) {
3268 			memset(cmd->sense_buffer +
3269 				cmd->se_cmd.scsi_sense_length, 0, padding);
3270 			pr_debug("Adding %u bytes of padding to"
3271 				" SENSE.\n", padding);
3272 		}
3273 
3274 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3275 				" Response PDU\n",
3276 				cmd->se_cmd.scsi_sense_length);
3277 	}
3278 
3279 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3280 						     data_buf_len);
3281 }
3282 
iscsit_convert_tcm_tmr_rsp(struct se_tmr_req * se_tmr)3283 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3284 {
3285 	switch (se_tmr->response) {
3286 	case TMR_FUNCTION_COMPLETE:
3287 		return ISCSI_TMF_RSP_COMPLETE;
3288 	case TMR_TASK_DOES_NOT_EXIST:
3289 		return ISCSI_TMF_RSP_NO_TASK;
3290 	case TMR_LUN_DOES_NOT_EXIST:
3291 		return ISCSI_TMF_RSP_NO_LUN;
3292 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3293 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3294 	case TMR_FUNCTION_REJECTED:
3295 	default:
3296 		return ISCSI_TMF_RSP_REJECTED;
3297 	}
3298 }
3299 
3300 void
iscsit_build_task_mgt_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_tm_rsp * hdr)3301 iscsit_build_task_mgt_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3302 			  struct iscsi_tm_rsp *hdr)
3303 {
3304 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3305 
3306 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3307 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3308 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3309 	hdr->itt		= cmd->init_task_tag;
3310 	cmd->stat_sn		= conn->stat_sn++;
3311 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3312 
3313 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3314 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3315 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3316 
3317 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3318 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3319 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3320 }
3321 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3322 
3323 static int
iscsit_send_task_mgt_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3324 iscsit_send_task_mgt_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3325 {
3326 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3327 
3328 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3329 
3330 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3331 }
3332 
3333 #define SENDTARGETS_BUF_LIMIT 32768U
3334 
3335 static int
iscsit_build_sendtargets_response(struct iscsit_cmd * cmd,enum iscsit_transport_type network_transport,int skip_bytes,bool * completed)3336 iscsit_build_sendtargets_response(struct iscsit_cmd *cmd,
3337 				  enum iscsit_transport_type network_transport,
3338 				  int skip_bytes, bool *completed)
3339 {
3340 	char *payload = NULL;
3341 	struct iscsit_conn *conn = cmd->conn;
3342 	struct iscsi_portal_group *tpg;
3343 	struct iscsi_tiqn *tiqn;
3344 	struct iscsi_tpg_np *tpg_np;
3345 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3346 	int target_name_printed;
3347 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3348 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3349 	bool active;
3350 
3351 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3352 			 SENDTARGETS_BUF_LIMIT);
3353 
3354 	payload = kzalloc(buffer_len, GFP_KERNEL);
3355 	if (!payload)
3356 		return -ENOMEM;
3357 
3358 	/*
3359 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3360 	 * explicit case..
3361 	 */
3362 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3363 		text_ptr = strchr(text_in, '=');
3364 		if (!text_ptr) {
3365 			pr_err("Unable to locate '=' string in text_in:"
3366 			       " %s\n", text_in);
3367 			kfree(payload);
3368 			return -EINVAL;
3369 		}
3370 		/*
3371 		 * Skip over '=' character..
3372 		 */
3373 		text_ptr += 1;
3374 	}
3375 
3376 	spin_lock(&tiqn_lock);
3377 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3378 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3379 		     strcmp(tiqn->tiqn, text_ptr)) {
3380 			continue;
3381 		}
3382 
3383 		target_name_printed = 0;
3384 
3385 		spin_lock(&tiqn->tiqn_tpg_lock);
3386 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3387 
3388 			/* If demo_mode_discovery=0 and generate_node_acls=0
3389 			 * (demo mode dislabed) do not return
3390 			 * TargetName+TargetAddress unless a NodeACL exists.
3391 			 */
3392 
3393 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3394 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3395 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3396 				cmd->conn->sess->sess_ops->InitiatorName))) {
3397 				continue;
3398 			}
3399 
3400 			spin_lock(&tpg->tpg_state_lock);
3401 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3402 			spin_unlock(&tpg->tpg_state_lock);
3403 
3404 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3405 				continue;
3406 
3407 			spin_lock(&tpg->tpg_np_lock);
3408 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3409 						tpg_np_list) {
3410 				struct iscsi_np *np = tpg_np->tpg_np;
3411 				struct sockaddr_storage *sockaddr;
3412 
3413 				if (np->np_network_transport != network_transport)
3414 					continue;
3415 
3416 				if (!target_name_printed) {
3417 					len = sprintf(buf, "TargetName=%s",
3418 						      tiqn->tiqn);
3419 					len += 1;
3420 
3421 					if ((len + payload_len) > buffer_len) {
3422 						spin_unlock(&tpg->tpg_np_lock);
3423 						spin_unlock(&tiqn->tiqn_tpg_lock);
3424 						end_of_buf = 1;
3425 						goto eob;
3426 					}
3427 
3428 					if (skip_bytes && len <= skip_bytes) {
3429 						skip_bytes -= len;
3430 					} else {
3431 						memcpy(payload + payload_len, buf, len);
3432 						payload_len += len;
3433 						target_name_printed = 1;
3434 						if (len > skip_bytes)
3435 							skip_bytes = 0;
3436 					}
3437 				}
3438 
3439 				if (inet_addr_is_any(&np->np_sockaddr))
3440 					sockaddr = &conn->local_sockaddr;
3441 				else
3442 					sockaddr = &np->np_sockaddr;
3443 
3444 				len = sprintf(buf, "TargetAddress="
3445 					      "%pISpc,%hu",
3446 					      sockaddr,
3447 					      tpg->tpgt);
3448 				len += 1;
3449 
3450 				if ((len + payload_len) > buffer_len) {
3451 					spin_unlock(&tpg->tpg_np_lock);
3452 					spin_unlock(&tiqn->tiqn_tpg_lock);
3453 					end_of_buf = 1;
3454 					goto eob;
3455 				}
3456 
3457 				if (skip_bytes && len <= skip_bytes) {
3458 					skip_bytes -= len;
3459 				} else {
3460 					memcpy(payload + payload_len, buf, len);
3461 					payload_len += len;
3462 					if (len > skip_bytes)
3463 						skip_bytes = 0;
3464 				}
3465 			}
3466 			spin_unlock(&tpg->tpg_np_lock);
3467 		}
3468 		spin_unlock(&tiqn->tiqn_tpg_lock);
3469 eob:
3470 		if (end_of_buf) {
3471 			*completed = false;
3472 			break;
3473 		}
3474 
3475 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3476 			break;
3477 	}
3478 	spin_unlock(&tiqn_lock);
3479 
3480 	cmd->buf_ptr = payload;
3481 
3482 	return payload_len;
3483 }
3484 
3485 int
iscsit_build_text_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_text_rsp * hdr,enum iscsit_transport_type network_transport)3486 iscsit_build_text_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3487 		      struct iscsi_text_rsp *hdr,
3488 		      enum iscsit_transport_type network_transport)
3489 {
3490 	int text_length, padding;
3491 	bool completed = true;
3492 
3493 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3494 							cmd->read_data_done,
3495 							&completed);
3496 	if (text_length < 0)
3497 		return text_length;
3498 
3499 	if (completed) {
3500 		hdr->flags = ISCSI_FLAG_CMD_FINAL;
3501 	} else {
3502 		hdr->flags = ISCSI_FLAG_TEXT_CONTINUE;
3503 		cmd->read_data_done += text_length;
3504 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3505 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3506 	}
3507 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3508 	padding = ((-text_length) & 3);
3509 	hton24(hdr->dlength, text_length);
3510 	hdr->itt = cmd->init_task_tag;
3511 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3512 	cmd->stat_sn = conn->stat_sn++;
3513 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3514 
3515 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3516 	/*
3517 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3518 	 * correctly increment MaxCmdSN for each response answering a
3519 	 * non immediate text request with a valid CmdSN.
3520 	 */
3521 	cmd->maxcmdsn_inc = 0;
3522 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3523 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3524 
3525 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3526 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3527 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3528 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3529 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3530 
3531 	return text_length + padding;
3532 }
3533 EXPORT_SYMBOL(iscsit_build_text_rsp);
3534 
iscsit_send_text_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3535 static int iscsit_send_text_rsp(
3536 	struct iscsit_cmd *cmd,
3537 	struct iscsit_conn *conn)
3538 {
3539 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3540 	int text_length;
3541 
3542 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3543 				conn->conn_transport->transport_type);
3544 	if (text_length < 0)
3545 		return text_length;
3546 
3547 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3548 						     cmd->buf_ptr,
3549 						     text_length);
3550 }
3551 
3552 void
iscsit_build_reject(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_reject * hdr)3553 iscsit_build_reject(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3554 		    struct iscsi_reject *hdr)
3555 {
3556 	hdr->opcode		= ISCSI_OP_REJECT;
3557 	hdr->reason		= cmd->reject_reason;
3558 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3559 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3560 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3561 	cmd->stat_sn		= conn->stat_sn++;
3562 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3563 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3564 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3565 
3566 }
3567 EXPORT_SYMBOL(iscsit_build_reject);
3568 
iscsit_send_reject(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3569 static int iscsit_send_reject(
3570 	struct iscsit_cmd *cmd,
3571 	struct iscsit_conn *conn)
3572 {
3573 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3574 
3575 	iscsit_build_reject(cmd, conn, hdr);
3576 
3577 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3578 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3579 
3580 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3581 						     cmd->buf_ptr,
3582 						     ISCSI_HDR_LEN);
3583 }
3584 
iscsit_thread_get_cpumask(struct iscsit_conn * conn)3585 void iscsit_thread_get_cpumask(struct iscsit_conn *conn)
3586 {
3587 	int ord, cpu;
3588 	cpumask_var_t conn_allowed_cpumask;
3589 
3590 	/*
3591 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3592 	 * within iscsit_start_kthreads()
3593 	 *
3594 	 * Here we use bitmap_id to determine which CPU that this
3595 	 * iSCSI connection's RX/TX threads will be scheduled to
3596 	 * execute upon.
3597 	 */
3598 	if (!zalloc_cpumask_var(&conn_allowed_cpumask, GFP_KERNEL)) {
3599 		ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3600 		for_each_online_cpu(cpu) {
3601 			if (ord-- == 0) {
3602 				cpumask_set_cpu(cpu, conn->conn_cpumask);
3603 				return;
3604 			}
3605 		}
3606 	} else {
3607 		cpumask_and(conn_allowed_cpumask, iscsit_global->allowed_cpumask,
3608 			cpu_online_mask);
3609 
3610 		cpumask_clear(conn->conn_cpumask);
3611 		ord = conn->bitmap_id % cpumask_weight(conn_allowed_cpumask);
3612 		for_each_cpu(cpu, conn_allowed_cpumask) {
3613 			if (ord-- == 0) {
3614 				cpumask_set_cpu(cpu, conn->conn_cpumask);
3615 				free_cpumask_var(conn_allowed_cpumask);
3616 				return;
3617 			}
3618 		}
3619 		free_cpumask_var(conn_allowed_cpumask);
3620 	}
3621 	/*
3622 	 * This should never be reached..
3623 	 */
3624 	dump_stack();
3625 	cpumask_setall(conn->conn_cpumask);
3626 }
3627 
iscsit_thread_reschedule(struct iscsit_conn * conn)3628 static void iscsit_thread_reschedule(struct iscsit_conn *conn)
3629 {
3630 	/*
3631 	 * If iscsit_global->allowed_cpumask modified, reschedule iSCSI
3632 	 * connection's RX/TX threads update conn->allowed_cpumask.
3633 	 */
3634 	if (!cpumask_equal(iscsit_global->allowed_cpumask,
3635 			   conn->allowed_cpumask)) {
3636 		iscsit_thread_get_cpumask(conn);
3637 		conn->conn_tx_reset_cpumask = 1;
3638 		conn->conn_rx_reset_cpumask = 1;
3639 		cpumask_copy(conn->allowed_cpumask,
3640 			     iscsit_global->allowed_cpumask);
3641 	}
3642 }
3643 
iscsit_thread_check_cpumask(struct iscsit_conn * conn,struct task_struct * p,int mode)3644 void iscsit_thread_check_cpumask(
3645 	struct iscsit_conn *conn,
3646 	struct task_struct *p,
3647 	int mode)
3648 {
3649 	/*
3650 	 * The TX and RX threads maybe call iscsit_thread_check_cpumask()
3651 	 * at the same time. The RX thread might be faster and return from
3652 	 * iscsit_thread_reschedule() with conn_rx_reset_cpumask set to 0.
3653 	 * Then the TX thread sets it back to 1.
3654 	 * The next time the RX thread loops, it sees conn_rx_reset_cpumask
3655 	 * set to 1 and calls set_cpus_allowed_ptr() again and set it to 0.
3656 	 */
3657 	iscsit_thread_reschedule(conn);
3658 
3659 	/*
3660 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3661 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3662 	 */
3663 	if (mode == 1) {
3664 		if (!conn->conn_tx_reset_cpumask)
3665 			return;
3666 	} else {
3667 		if (!conn->conn_rx_reset_cpumask)
3668 			return;
3669 	}
3670 
3671 	/*
3672 	 * Update the CPU mask for this single kthread so that
3673 	 * both TX and RX kthreads are scheduled to run on the
3674 	 * same CPU.
3675 	 */
3676 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3677 	if (mode == 1)
3678 		conn->conn_tx_reset_cpumask = 0;
3679 	else
3680 		conn->conn_rx_reset_cpumask = 0;
3681 }
3682 EXPORT_SYMBOL(iscsit_thread_check_cpumask);
3683 
3684 int
iscsit_immediate_queue(struct iscsit_conn * conn,struct iscsit_cmd * cmd,int state)3685 iscsit_immediate_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
3686 {
3687 	int ret;
3688 
3689 	switch (state) {
3690 	case ISTATE_SEND_R2T:
3691 		ret = iscsit_send_r2t(cmd, conn);
3692 		if (ret < 0)
3693 			goto err;
3694 		break;
3695 	case ISTATE_REMOVE:
3696 		spin_lock_bh(&conn->cmd_lock);
3697 		list_del_init(&cmd->i_conn_node);
3698 		spin_unlock_bh(&conn->cmd_lock);
3699 
3700 		iscsit_free_cmd(cmd, false);
3701 		break;
3702 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3703 		iscsit_mod_nopin_response_timer(conn);
3704 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3705 		if (ret < 0)
3706 			goto err;
3707 		break;
3708 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3709 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3710 		if (ret < 0)
3711 			goto err;
3712 		break;
3713 	default:
3714 		pr_err("Unknown Opcode: 0x%02x ITT:"
3715 		       " 0x%08x, i_state: %d on CID: %hu\n",
3716 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3717 		       conn->cid);
3718 		goto err;
3719 	}
3720 
3721 	return 0;
3722 
3723 err:
3724 	return -1;
3725 }
3726 EXPORT_SYMBOL(iscsit_immediate_queue);
3727 
3728 static int
iscsit_handle_immediate_queue(struct iscsit_conn * conn)3729 iscsit_handle_immediate_queue(struct iscsit_conn *conn)
3730 {
3731 	struct iscsit_transport *t = conn->conn_transport;
3732 	struct iscsi_queue_req *qr;
3733 	struct iscsit_cmd *cmd;
3734 	u8 state;
3735 	int ret;
3736 
3737 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3738 		atomic_set(&conn->check_immediate_queue, 0);
3739 		cmd = qr->cmd;
3740 		state = qr->state;
3741 		kmem_cache_free(lio_qr_cache, qr);
3742 
3743 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3744 		if (ret < 0)
3745 			return ret;
3746 	}
3747 
3748 	return 0;
3749 }
3750 
3751 int
iscsit_response_queue(struct iscsit_conn * conn,struct iscsit_cmd * cmd,int state)3752 iscsit_response_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
3753 {
3754 	int ret;
3755 
3756 check_rsp_state:
3757 	switch (state) {
3758 	case ISTATE_SEND_DATAIN:
3759 		ret = iscsit_send_datain(cmd, conn);
3760 		if (ret < 0)
3761 			goto err;
3762 		else if (!ret)
3763 			/* more drs */
3764 			goto check_rsp_state;
3765 		else if (ret == 1) {
3766 			/* all done */
3767 			spin_lock_bh(&cmd->istate_lock);
3768 			cmd->i_state = ISTATE_SENT_STATUS;
3769 			spin_unlock_bh(&cmd->istate_lock);
3770 
3771 			if (atomic_read(&conn->check_immediate_queue))
3772 				return 1;
3773 
3774 			return 0;
3775 		} else if (ret == 2) {
3776 			/* Still must send status,
3777 			   SCF_TRANSPORT_TASK_SENSE was set */
3778 			spin_lock_bh(&cmd->istate_lock);
3779 			cmd->i_state = ISTATE_SEND_STATUS;
3780 			spin_unlock_bh(&cmd->istate_lock);
3781 			state = ISTATE_SEND_STATUS;
3782 			goto check_rsp_state;
3783 		}
3784 
3785 		break;
3786 	case ISTATE_SEND_STATUS:
3787 	case ISTATE_SEND_STATUS_RECOVERY:
3788 		ret = iscsit_send_response(cmd, conn);
3789 		break;
3790 	case ISTATE_SEND_LOGOUTRSP:
3791 		ret = iscsit_send_logout(cmd, conn);
3792 		break;
3793 	case ISTATE_SEND_ASYNCMSG:
3794 		ret = iscsit_send_conn_drop_async_message(
3795 			cmd, conn);
3796 		break;
3797 	case ISTATE_SEND_NOPIN:
3798 		ret = iscsit_send_nopin(cmd, conn);
3799 		break;
3800 	case ISTATE_SEND_REJECT:
3801 		ret = iscsit_send_reject(cmd, conn);
3802 		break;
3803 	case ISTATE_SEND_TASKMGTRSP:
3804 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3805 		if (ret != 0)
3806 			break;
3807 		ret = iscsit_tmr_post_handler(cmd, conn);
3808 		if (ret != 0)
3809 			iscsit_fall_back_to_erl0(conn->sess);
3810 		break;
3811 	case ISTATE_SEND_TEXTRSP:
3812 		ret = iscsit_send_text_rsp(cmd, conn);
3813 		break;
3814 	default:
3815 		pr_err("Unknown Opcode: 0x%02x ITT:"
3816 		       " 0x%08x, i_state: %d on CID: %hu\n",
3817 		       cmd->iscsi_opcode, cmd->init_task_tag,
3818 		       state, conn->cid);
3819 		goto err;
3820 	}
3821 	if (ret < 0)
3822 		goto err;
3823 
3824 	switch (state) {
3825 	case ISTATE_SEND_LOGOUTRSP:
3826 		if (!iscsit_logout_post_handler(cmd, conn))
3827 			return -ECONNRESET;
3828 		fallthrough;
3829 	case ISTATE_SEND_STATUS:
3830 	case ISTATE_SEND_ASYNCMSG:
3831 	case ISTATE_SEND_NOPIN:
3832 	case ISTATE_SEND_STATUS_RECOVERY:
3833 	case ISTATE_SEND_TEXTRSP:
3834 	case ISTATE_SEND_TASKMGTRSP:
3835 	case ISTATE_SEND_REJECT:
3836 		spin_lock_bh(&cmd->istate_lock);
3837 		cmd->i_state = ISTATE_SENT_STATUS;
3838 		spin_unlock_bh(&cmd->istate_lock);
3839 		break;
3840 	default:
3841 		pr_err("Unknown Opcode: 0x%02x ITT:"
3842 		       " 0x%08x, i_state: %d on CID: %hu\n",
3843 		       cmd->iscsi_opcode, cmd->init_task_tag,
3844 		       cmd->i_state, conn->cid);
3845 		goto err;
3846 	}
3847 
3848 	if (atomic_read(&conn->check_immediate_queue))
3849 		return 1;
3850 
3851 	return 0;
3852 
3853 err:
3854 	return -1;
3855 }
3856 EXPORT_SYMBOL(iscsit_response_queue);
3857 
iscsit_handle_response_queue(struct iscsit_conn * conn)3858 static int iscsit_handle_response_queue(struct iscsit_conn *conn)
3859 {
3860 	struct iscsit_transport *t = conn->conn_transport;
3861 	struct iscsi_queue_req *qr;
3862 	struct iscsit_cmd *cmd;
3863 	u8 state;
3864 	int ret;
3865 
3866 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3867 		cmd = qr->cmd;
3868 		state = qr->state;
3869 		kmem_cache_free(lio_qr_cache, qr);
3870 
3871 		ret = t->iscsit_response_queue(conn, cmd, state);
3872 		if (ret == 1 || ret < 0)
3873 			return ret;
3874 	}
3875 
3876 	return 0;
3877 }
3878 
iscsi_target_tx_thread(void * arg)3879 int iscsi_target_tx_thread(void *arg)
3880 {
3881 	int ret = 0;
3882 	struct iscsit_conn *conn = arg;
3883 	bool conn_freed = false;
3884 
3885 	/*
3886 	 * Allow ourselves to be interrupted by SIGINT so that a
3887 	 * connection recovery / failure event can be triggered externally.
3888 	 */
3889 	allow_signal(SIGINT);
3890 
3891 	while (!kthread_should_stop()) {
3892 		/*
3893 		 * Ensure that both TX and RX per connection kthreads
3894 		 * are scheduled to run on the same CPU.
3895 		 */
3896 		iscsit_thread_check_cpumask(conn, current, 1);
3897 
3898 		wait_event_interruptible(conn->queues_wq,
3899 					 !iscsit_conn_all_queues_empty(conn));
3900 
3901 		if (signal_pending(current))
3902 			goto transport_err;
3903 
3904 get_immediate:
3905 		ret = iscsit_handle_immediate_queue(conn);
3906 		if (ret < 0)
3907 			goto transport_err;
3908 
3909 		ret = iscsit_handle_response_queue(conn);
3910 		if (ret == 1) {
3911 			goto get_immediate;
3912 		} else if (ret == -ECONNRESET) {
3913 			conn_freed = true;
3914 			goto out;
3915 		} else if (ret < 0) {
3916 			goto transport_err;
3917 		}
3918 	}
3919 
3920 transport_err:
3921 	/*
3922 	 * Avoid the normal connection failure code-path if this connection
3923 	 * is still within LOGIN mode, and iscsi_np process context is
3924 	 * responsible for cleaning up the early connection failure.
3925 	 */
3926 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3927 		iscsit_take_action_for_connection_exit(conn, &conn_freed);
3928 out:
3929 	if (!conn_freed) {
3930 		while (!kthread_should_stop()) {
3931 			msleep(100);
3932 		}
3933 	}
3934 	return 0;
3935 }
3936 
iscsi_target_rx_opcode(struct iscsit_conn * conn,unsigned char * buf)3937 static int iscsi_target_rx_opcode(struct iscsit_conn *conn, unsigned char *buf)
3938 {
3939 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3940 	struct iscsit_cmd *cmd;
3941 	int ret = 0;
3942 
3943 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3944 	case ISCSI_OP_SCSI_CMD:
3945 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3946 		if (!cmd)
3947 			goto reject;
3948 
3949 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3950 		break;
3951 	case ISCSI_OP_SCSI_DATA_OUT:
3952 		ret = iscsit_handle_data_out(conn, buf);
3953 		break;
3954 	case ISCSI_OP_NOOP_OUT:
3955 		cmd = NULL;
3956 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3957 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3958 			if (!cmd)
3959 				goto reject;
3960 		}
3961 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3962 		break;
3963 	case ISCSI_OP_SCSI_TMFUNC:
3964 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3965 		if (!cmd)
3966 			goto reject;
3967 
3968 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3969 		break;
3970 	case ISCSI_OP_TEXT:
3971 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3972 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3973 			if (!cmd)
3974 				goto reject;
3975 		} else {
3976 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3977 			if (!cmd)
3978 				goto reject;
3979 		}
3980 
3981 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3982 		break;
3983 	case ISCSI_OP_LOGOUT:
3984 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3985 		if (!cmd)
3986 			goto reject;
3987 
3988 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3989 		if (ret > 0)
3990 			wait_for_completion_timeout(&conn->conn_logout_comp,
3991 					SECONDS_FOR_LOGOUT_COMP * HZ);
3992 		break;
3993 	case ISCSI_OP_SNACK:
3994 		ret = iscsit_handle_snack(conn, buf);
3995 		break;
3996 	default:
3997 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
3998 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
3999 			pr_err("Cannot recover from unknown"
4000 			" opcode while ERL=0, closing iSCSI connection.\n");
4001 			return -1;
4002 		}
4003 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
4004 		       " closing iSCSI connection.\n");
4005 		ret = -1;
4006 		break;
4007 	}
4008 
4009 	return ret;
4010 reject:
4011 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4012 }
4013 
iscsi_target_check_conn_state(struct iscsit_conn * conn)4014 static bool iscsi_target_check_conn_state(struct iscsit_conn *conn)
4015 {
4016 	bool ret;
4017 
4018 	spin_lock_bh(&conn->state_lock);
4019 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
4020 	spin_unlock_bh(&conn->state_lock);
4021 
4022 	return ret;
4023 }
4024 
iscsit_get_rx_pdu(struct iscsit_conn * conn)4025 static void iscsit_get_rx_pdu(struct iscsit_conn *conn)
4026 {
4027 	int ret;
4028 	u8 *buffer, *tmp_buf, opcode;
4029 	u32 checksum = 0, digest = 0;
4030 	struct iscsi_hdr *hdr;
4031 	struct kvec iov;
4032 
4033 	buffer = kcalloc(ISCSI_HDR_LEN, sizeof(*buffer), GFP_KERNEL);
4034 	if (!buffer)
4035 		return;
4036 
4037 	while (!kthread_should_stop()) {
4038 		/*
4039 		 * Ensure that both TX and RX per connection kthreads
4040 		 * are scheduled to run on the same CPU.
4041 		 */
4042 		iscsit_thread_check_cpumask(conn, current, 0);
4043 
4044 		memset(&iov, 0, sizeof(struct kvec));
4045 
4046 		iov.iov_base	= buffer;
4047 		iov.iov_len	= ISCSI_HDR_LEN;
4048 
4049 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4050 		if (ret != ISCSI_HDR_LEN) {
4051 			iscsit_rx_thread_wait_for_tcp(conn);
4052 			break;
4053 		}
4054 
4055 		hdr = (struct iscsi_hdr *) buffer;
4056 		if (hdr->hlength) {
4057 			iov.iov_len = hdr->hlength * 4;
4058 			tmp_buf = krealloc(buffer,
4059 					  ISCSI_HDR_LEN + iov.iov_len,
4060 					  GFP_KERNEL);
4061 			if (!tmp_buf)
4062 				break;
4063 
4064 			buffer = tmp_buf;
4065 			iov.iov_base = &buffer[ISCSI_HDR_LEN];
4066 
4067 			ret = rx_data(conn, &iov, 1, iov.iov_len);
4068 			if (ret != iov.iov_len) {
4069 				iscsit_rx_thread_wait_for_tcp(conn);
4070 				break;
4071 			}
4072 		}
4073 
4074 		if (conn->conn_ops->HeaderDigest) {
4075 			iov.iov_base	= &digest;
4076 			iov.iov_len	= ISCSI_CRC_LEN;
4077 
4078 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4079 			if (ret != ISCSI_CRC_LEN) {
4080 				iscsit_rx_thread_wait_for_tcp(conn);
4081 				break;
4082 			}
4083 
4084 			checksum = iscsit_crc_buf(buffer, ISCSI_HDR_LEN, 0,
4085 						  NULL);
4086 			if (digest != checksum) {
4087 				pr_err("HeaderDigest CRC32C failed,"
4088 					" received 0x%08x, computed 0x%08x\n",
4089 					digest, checksum);
4090 				/*
4091 				 * Set the PDU to 0xff so it will intentionally
4092 				 * hit default in the switch below.
4093 				 */
4094 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4095 				atomic_long_inc(&conn->sess->conn_digest_errors);
4096 			} else {
4097 				pr_debug("Got HeaderDigest CRC32C"
4098 						" 0x%08x\n", checksum);
4099 			}
4100 		}
4101 
4102 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4103 			break;
4104 
4105 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4106 
4107 		if (conn->sess->sess_ops->SessionType &&
4108 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4109 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4110 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4111 			" while in Discovery Session, rejecting.\n", opcode);
4112 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4113 					  buffer);
4114 			break;
4115 		}
4116 
4117 		ret = iscsi_target_rx_opcode(conn, buffer);
4118 		if (ret < 0)
4119 			break;
4120 	}
4121 
4122 	kfree(buffer);
4123 }
4124 
iscsi_target_rx_thread(void * arg)4125 int iscsi_target_rx_thread(void *arg)
4126 {
4127 	int rc;
4128 	struct iscsit_conn *conn = arg;
4129 	bool conn_freed = false;
4130 
4131 	/*
4132 	 * Allow ourselves to be interrupted by SIGINT so that a
4133 	 * connection recovery / failure event can be triggered externally.
4134 	 */
4135 	allow_signal(SIGINT);
4136 	/*
4137 	 * Wait for iscsi_post_login_handler() to complete before allowing
4138 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4139 	 */
4140 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4141 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4142 		goto out;
4143 
4144 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4145 		return 0;
4146 
4147 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4148 
4149 	if (!signal_pending(current))
4150 		atomic_set(&conn->transport_failed, 1);
4151 	iscsit_take_action_for_connection_exit(conn, &conn_freed);
4152 
4153 out:
4154 	if (!conn_freed) {
4155 		while (!kthread_should_stop()) {
4156 			msleep(100);
4157 		}
4158 	}
4159 
4160 	return 0;
4161 }
4162 
iscsit_release_commands_from_conn(struct iscsit_conn * conn)4163 static void iscsit_release_commands_from_conn(struct iscsit_conn *conn)
4164 {
4165 	LIST_HEAD(tmp_list);
4166 	struct iscsit_cmd *cmd = NULL, *cmd_tmp = NULL;
4167 	struct iscsit_session *sess = conn->sess;
4168 	/*
4169 	 * We expect this function to only ever be called from either RX or TX
4170 	 * thread context via iscsit_close_connection() once the other context
4171 	 * has been reset -> returned sleeping pre-handler state.
4172 	 */
4173 	spin_lock_bh(&conn->cmd_lock);
4174 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4175 
4176 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4177 		struct se_cmd *se_cmd = &cmd->se_cmd;
4178 
4179 		if (!se_cmd->se_tfo)
4180 			continue;
4181 
4182 		spin_lock_irq(&se_cmd->t_state_lock);
4183 		if (se_cmd->transport_state & CMD_T_ABORTED) {
4184 			if (!(se_cmd->transport_state & CMD_T_TAS))
4185 				/*
4186 				 * LIO's abort path owns the cleanup for this,
4187 				 * so put it back on the list and let
4188 				 * aborted_task handle it.
4189 				 */
4190 				list_move_tail(&cmd->i_conn_node,
4191 					       &conn->conn_cmd_list);
4192 		} else {
4193 			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4194 		}
4195 
4196 		if (cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
4197 			/*
4198 			 * We never submitted the cmd to LIO core, so we have
4199 			 * to tell LIO to perform the completion process.
4200 			 */
4201 			spin_unlock_irq(&se_cmd->t_state_lock);
4202 			target_complete_cmd(&cmd->se_cmd, SAM_STAT_TASK_ABORTED);
4203 			continue;
4204 		}
4205 		spin_unlock_irq(&se_cmd->t_state_lock);
4206 	}
4207 	spin_unlock_bh(&conn->cmd_lock);
4208 
4209 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4210 		list_del_init(&cmd->i_conn_node);
4211 
4212 		iscsit_increment_maxcmdsn(cmd, sess);
4213 		iscsit_free_cmd(cmd, true);
4214 
4215 	}
4216 
4217 	/*
4218 	 * Wait on commands that were cleaned up via the aborted_task path.
4219 	 * LLDs that implement iscsit_wait_conn will already have waited for
4220 	 * commands.
4221 	 */
4222 	if (!conn->conn_transport->iscsit_wait_conn) {
4223 		target_stop_cmd_counter(conn->cmd_cnt);
4224 		target_wait_for_cmds(conn->cmd_cnt);
4225 	}
4226 }
4227 
iscsit_stop_timers_for_cmds(struct iscsit_conn * conn)4228 static void iscsit_stop_timers_for_cmds(
4229 	struct iscsit_conn *conn)
4230 {
4231 	struct iscsit_cmd *cmd;
4232 
4233 	spin_lock_bh(&conn->cmd_lock);
4234 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4235 		if (cmd->data_direction == DMA_TO_DEVICE)
4236 			iscsit_stop_dataout_timer(cmd);
4237 	}
4238 	spin_unlock_bh(&conn->cmd_lock);
4239 }
4240 
iscsit_close_connection(struct iscsit_conn * conn)4241 int iscsit_close_connection(
4242 	struct iscsit_conn *conn)
4243 {
4244 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4245 	struct iscsit_session	*sess = conn->sess;
4246 
4247 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4248 		" %u\n", conn->cid, sess->sid);
4249 	/*
4250 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4251 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4252 	 * sleeping and the logout response never got sent because the
4253 	 * connection failed.
4254 	 *
4255 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4256 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4257 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4258 	 * and to avoid iscsit_conn pointer dereference in iser-target code.
4259 	 */
4260 	if (!conn->conn_transport->rdma_shutdown)
4261 		complete(&conn->conn_logout_comp);
4262 
4263 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4264 		if (conn->tx_thread &&
4265 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4266 			send_sig(SIGINT, conn->tx_thread, 1);
4267 			kthread_stop(conn->tx_thread);
4268 		}
4269 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4270 		if (conn->rx_thread &&
4271 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4272 			send_sig(SIGINT, conn->rx_thread, 1);
4273 			kthread_stop(conn->rx_thread);
4274 		}
4275 	}
4276 
4277 	spin_lock(&iscsit_global->ts_bitmap_lock);
4278 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4279 			      get_order(1));
4280 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4281 
4282 	iscsit_stop_timers_for_cmds(conn);
4283 	iscsit_stop_nopin_timer(conn);
4284 	iscsit_stop_nopin_response_timer(conn);
4285 
4286 	if (conn->conn_transport->iscsit_wait_conn)
4287 		conn->conn_transport->iscsit_wait_conn(conn);
4288 
4289 	/*
4290 	 * During Connection recovery drop unacknowledged out of order
4291 	 * commands for this connection, and prepare the other commands
4292 	 * for reallegiance.
4293 	 *
4294 	 * During normal operation clear the out of order commands (but
4295 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4296 	 * struct iscsit_cmds.
4297 	 */
4298 	if (atomic_read(&conn->connection_recovery)) {
4299 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4300 		iscsit_prepare_cmds_for_reallegiance(conn);
4301 	} else {
4302 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4303 		iscsit_release_commands_from_conn(conn);
4304 	}
4305 	iscsit_free_queue_reqs_for_conn(conn);
4306 
4307 	/*
4308 	 * Handle decrementing session or connection usage count if
4309 	 * a logout response was not able to be sent because the
4310 	 * connection failed.  Fall back to Session Recovery here.
4311 	 */
4312 	if (atomic_read(&conn->conn_logout_remove)) {
4313 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4314 			iscsit_dec_conn_usage_count(conn);
4315 			iscsit_dec_session_usage_count(sess);
4316 		}
4317 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4318 			iscsit_dec_conn_usage_count(conn);
4319 
4320 		atomic_set(&conn->conn_logout_remove, 0);
4321 		atomic_set(&sess->session_reinstatement, 0);
4322 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4323 	}
4324 
4325 	spin_lock_bh(&sess->conn_lock);
4326 	list_del(&conn->conn_list);
4327 
4328 	/*
4329 	 * Attempt to let the Initiator know this connection failed by
4330 	 * sending an Connection Dropped Async Message on another
4331 	 * active connection.
4332 	 */
4333 	if (atomic_read(&conn->connection_recovery))
4334 		iscsit_build_conn_drop_async_message(conn);
4335 
4336 	spin_unlock_bh(&sess->conn_lock);
4337 
4338 	/*
4339 	 * If connection reinstatement is being performed on this connection,
4340 	 * up the connection reinstatement semaphore that is being blocked on
4341 	 * in iscsit_cause_connection_reinstatement().
4342 	 */
4343 	spin_lock_bh(&conn->state_lock);
4344 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4345 		spin_unlock_bh(&conn->state_lock);
4346 		complete(&conn->conn_wait_comp);
4347 		wait_for_completion(&conn->conn_post_wait_comp);
4348 		spin_lock_bh(&conn->state_lock);
4349 	}
4350 
4351 	/*
4352 	 * If connection reinstatement is being performed on this connection
4353 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4354 	 * connection wait rcfr semaphore that is being blocked on
4355 	 * an iscsit_connection_reinstatement_rcfr().
4356 	 */
4357 	if (atomic_read(&conn->connection_wait_rcfr)) {
4358 		spin_unlock_bh(&conn->state_lock);
4359 		complete(&conn->conn_wait_rcfr_comp);
4360 		wait_for_completion(&conn->conn_post_wait_comp);
4361 		spin_lock_bh(&conn->state_lock);
4362 	}
4363 	atomic_set(&conn->connection_reinstatement, 1);
4364 	spin_unlock_bh(&conn->state_lock);
4365 
4366 	/*
4367 	 * If any other processes are accessing this connection pointer we
4368 	 * must wait until they have completed.
4369 	 */
4370 	iscsit_check_conn_usage_count(conn);
4371 
4372 	if (conn->sock)
4373 		sock_release(conn->sock);
4374 
4375 	if (conn->conn_transport->iscsit_free_conn)
4376 		conn->conn_transport->iscsit_free_conn(conn);
4377 
4378 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4379 	conn->conn_state = TARG_CONN_STATE_FREE;
4380 	iscsit_free_conn(conn);
4381 
4382 	spin_lock_bh(&sess->conn_lock);
4383 	atomic_dec(&sess->nconn);
4384 	pr_debug("Decremented iSCSI connection count to %d from node:"
4385 		" %s\n", atomic_read(&sess->nconn),
4386 		sess->sess_ops->InitiatorName);
4387 	/*
4388 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4389 	 * Session that they all fail.
4390 	 */
4391 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4392 	     !atomic_read(&sess->session_logout))
4393 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4394 
4395 	/*
4396 	 * If this was not the last connection in the session, and we are
4397 	 * performing session reinstatement or falling back to ERL=0, call
4398 	 * iscsit_stop_session() without sleeping to shutdown the other
4399 	 * active connections.
4400 	 */
4401 	if (atomic_read(&sess->nconn)) {
4402 		if (!atomic_read(&sess->session_reinstatement) &&
4403 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4404 			spin_unlock_bh(&sess->conn_lock);
4405 			return 0;
4406 		}
4407 		if (!atomic_read(&sess->session_stop_active)) {
4408 			atomic_set(&sess->session_stop_active, 1);
4409 			spin_unlock_bh(&sess->conn_lock);
4410 			iscsit_stop_session(sess, 0, 0);
4411 			return 0;
4412 		}
4413 		spin_unlock_bh(&sess->conn_lock);
4414 		return 0;
4415 	}
4416 
4417 	/*
4418 	 * If this was the last connection in the session and one of the
4419 	 * following is occurring:
4420 	 *
4421 	 * Session Reinstatement is not being performed, and are falling back
4422 	 * to ERL=0 call iscsit_close_session().
4423 	 *
4424 	 * Session Logout was requested.  iscsit_close_session() will be called
4425 	 * elsewhere.
4426 	 *
4427 	 * Session Continuation is not being performed, start the Time2Retain
4428 	 * handler and check if sleep_on_sess_wait_sem is active.
4429 	 */
4430 	if (!atomic_read(&sess->session_reinstatement) &&
4431 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4432 		spin_unlock_bh(&sess->conn_lock);
4433 		complete_all(&sess->session_wait_comp);
4434 		iscsit_close_session(sess, true);
4435 
4436 		return 0;
4437 	} else if (atomic_read(&sess->session_logout)) {
4438 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4439 		sess->session_state = TARG_SESS_STATE_FREE;
4440 
4441 		if (atomic_read(&sess->session_close)) {
4442 			spin_unlock_bh(&sess->conn_lock);
4443 			complete_all(&sess->session_wait_comp);
4444 			iscsit_close_session(sess, true);
4445 		} else {
4446 			spin_unlock_bh(&sess->conn_lock);
4447 		}
4448 
4449 		return 0;
4450 	} else {
4451 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4452 		sess->session_state = TARG_SESS_STATE_FAILED;
4453 
4454 		if (!atomic_read(&sess->session_continuation))
4455 			iscsit_start_time2retain_handler(sess);
4456 
4457 		if (atomic_read(&sess->session_close)) {
4458 			spin_unlock_bh(&sess->conn_lock);
4459 			complete_all(&sess->session_wait_comp);
4460 			iscsit_close_session(sess, true);
4461 		} else {
4462 			spin_unlock_bh(&sess->conn_lock);
4463 		}
4464 
4465 		return 0;
4466 	}
4467 }
4468 
4469 /*
4470  * If the iSCSI Session for the iSCSI Initiator Node exists,
4471  * forcefully shutdown the iSCSI NEXUS.
4472  */
iscsit_close_session(struct iscsit_session * sess,bool can_sleep)4473 int iscsit_close_session(struct iscsit_session *sess, bool can_sleep)
4474 {
4475 	struct iscsi_portal_group *tpg = sess->tpg;
4476 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4477 
4478 	if (atomic_read(&sess->nconn)) {
4479 		pr_err("%d connection(s) still exist for iSCSI session"
4480 			" to %s\n", atomic_read(&sess->nconn),
4481 			sess->sess_ops->InitiatorName);
4482 		BUG();
4483 	}
4484 
4485 	spin_lock_bh(&se_tpg->session_lock);
4486 	atomic_set(&sess->session_logout, 1);
4487 	atomic_set(&sess->session_reinstatement, 1);
4488 	iscsit_stop_time2retain_timer(sess);
4489 	spin_unlock_bh(&se_tpg->session_lock);
4490 
4491 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4492 		iscsit_free_connection_recovery_entries(sess);
4493 
4494 	/*
4495 	 * transport_deregister_session_configfs() will clear the
4496 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4497 	 * can be setting it again with __transport_register_session() in
4498 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4499 	 * completes in iscsi_np context.
4500 	 */
4501 	transport_deregister_session_configfs(sess->se_sess);
4502 
4503 	/*
4504 	 * If any other processes are accessing this session pointer we must
4505 	 * wait until they have completed.  If we are in an interrupt (the
4506 	 * time2retain handler) and contain and active session usage count we
4507 	 * restart the timer and exit.
4508 	 */
4509 	if (iscsit_check_session_usage_count(sess, can_sleep)) {
4510 		atomic_set(&sess->session_logout, 0);
4511 		iscsit_start_time2retain_handler(sess);
4512 		return 0;
4513 	}
4514 
4515 	transport_deregister_session(sess->se_sess);
4516 
4517 	iscsit_free_all_ooo_cmdsns(sess);
4518 
4519 	spin_lock_bh(&se_tpg->session_lock);
4520 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4521 	sess->session_state = TARG_SESS_STATE_FREE;
4522 	pr_debug("Released iSCSI session from node: %s\n",
4523 			sess->sess_ops->InitiatorName);
4524 	tpg->nsessions--;
4525 	if (tpg->tpg_tiqn)
4526 		tpg->tpg_tiqn->tiqn_nsessions--;
4527 
4528 	pr_debug("Decremented number of active iSCSI Sessions on"
4529 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4530 
4531 	ida_free(&sess_ida, sess->session_index);
4532 	kfree(sess->sess_ops);
4533 	sess->sess_ops = NULL;
4534 	spin_unlock_bh(&se_tpg->session_lock);
4535 
4536 	kfree(sess);
4537 	return 0;
4538 }
4539 
iscsit_logout_post_handler_closesession(struct iscsit_conn * conn)4540 static void iscsit_logout_post_handler_closesession(
4541 	struct iscsit_conn *conn)
4542 {
4543 	struct iscsit_session *sess = conn->sess;
4544 	int sleep = 1;
4545 	/*
4546 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4547 	 * context during session logout, so clear tx_thread_active and
4548 	 * sleep if iscsit_close_connection() has not already occured.
4549 	 *
4550 	 * Since iser-target invokes this logic from it's own workqueue,
4551 	 * always sleep waiting for RX/TX thread shutdown to complete
4552 	 * within iscsit_close_connection().
4553 	 */
4554 	if (!conn->conn_transport->rdma_shutdown) {
4555 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4556 		if (!sleep)
4557 			return;
4558 	}
4559 
4560 	atomic_set(&conn->conn_logout_remove, 0);
4561 	complete(&conn->conn_logout_comp);
4562 
4563 	iscsit_dec_conn_usage_count(conn);
4564 	atomic_set(&sess->session_close, 1);
4565 	iscsit_stop_session(sess, sleep, sleep);
4566 	iscsit_dec_session_usage_count(sess);
4567 }
4568 
iscsit_logout_post_handler_samecid(struct iscsit_conn * conn)4569 static void iscsit_logout_post_handler_samecid(
4570 	struct iscsit_conn *conn)
4571 {
4572 	int sleep = 1;
4573 
4574 	if (!conn->conn_transport->rdma_shutdown) {
4575 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4576 		if (!sleep)
4577 			return;
4578 	}
4579 
4580 	atomic_set(&conn->conn_logout_remove, 0);
4581 	complete(&conn->conn_logout_comp);
4582 
4583 	iscsit_cause_connection_reinstatement(conn, sleep);
4584 	iscsit_dec_conn_usage_count(conn);
4585 }
4586 
iscsit_logout_post_handler_diffcid(struct iscsit_conn * conn,u16 cid)4587 static void iscsit_logout_post_handler_diffcid(
4588 	struct iscsit_conn *conn,
4589 	u16 cid)
4590 {
4591 	struct iscsit_conn *l_conn;
4592 	struct iscsit_session *sess = conn->sess;
4593 	bool conn_found = false;
4594 
4595 	if (!sess)
4596 		return;
4597 
4598 	spin_lock_bh(&sess->conn_lock);
4599 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4600 		if (l_conn->cid == cid) {
4601 			iscsit_inc_conn_usage_count(l_conn);
4602 			conn_found = true;
4603 			break;
4604 		}
4605 	}
4606 	spin_unlock_bh(&sess->conn_lock);
4607 
4608 	if (!conn_found)
4609 		return;
4610 
4611 	if (l_conn->sock)
4612 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4613 
4614 	spin_lock_bh(&l_conn->state_lock);
4615 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4616 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4617 	spin_unlock_bh(&l_conn->state_lock);
4618 
4619 	iscsit_cause_connection_reinstatement(l_conn, 1);
4620 	iscsit_dec_conn_usage_count(l_conn);
4621 }
4622 
4623 /*
4624  *	Return of 0 causes the TX thread to restart.
4625  */
iscsit_logout_post_handler(struct iscsit_cmd * cmd,struct iscsit_conn * conn)4626 int iscsit_logout_post_handler(
4627 	struct iscsit_cmd *cmd,
4628 	struct iscsit_conn *conn)
4629 {
4630 	int ret = 0;
4631 
4632 	switch (cmd->logout_reason) {
4633 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4634 		switch (cmd->logout_response) {
4635 		case ISCSI_LOGOUT_SUCCESS:
4636 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4637 		default:
4638 			iscsit_logout_post_handler_closesession(conn);
4639 			break;
4640 		}
4641 		break;
4642 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4643 		if (conn->cid == cmd->logout_cid) {
4644 			switch (cmd->logout_response) {
4645 			case ISCSI_LOGOUT_SUCCESS:
4646 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4647 			default:
4648 				iscsit_logout_post_handler_samecid(conn);
4649 				break;
4650 			}
4651 		} else {
4652 			switch (cmd->logout_response) {
4653 			case ISCSI_LOGOUT_SUCCESS:
4654 				iscsit_logout_post_handler_diffcid(conn,
4655 					cmd->logout_cid);
4656 				break;
4657 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4658 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4659 			default:
4660 				break;
4661 			}
4662 			ret = 1;
4663 		}
4664 		break;
4665 	case ISCSI_LOGOUT_REASON_RECOVERY:
4666 		switch (cmd->logout_response) {
4667 		case ISCSI_LOGOUT_SUCCESS:
4668 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4669 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4670 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4671 		default:
4672 			break;
4673 		}
4674 		ret = 1;
4675 		break;
4676 	default:
4677 		break;
4678 
4679 	}
4680 	return ret;
4681 }
4682 EXPORT_SYMBOL(iscsit_logout_post_handler);
4683 
iscsit_stop_session(struct iscsit_session * sess,int session_sleep,int connection_sleep)4684 void iscsit_stop_session(
4685 	struct iscsit_session *sess,
4686 	int session_sleep,
4687 	int connection_sleep)
4688 {
4689 	u16 conn_count = atomic_read(&sess->nconn);
4690 	struct iscsit_conn *conn, *conn_tmp = NULL;
4691 	int is_last;
4692 
4693 	spin_lock_bh(&sess->conn_lock);
4694 
4695 	if (connection_sleep) {
4696 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4697 				conn_list) {
4698 			if (conn_count == 0)
4699 				break;
4700 
4701 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4702 				is_last = 1;
4703 			} else {
4704 				iscsit_inc_conn_usage_count(conn_tmp);
4705 				is_last = 0;
4706 			}
4707 			iscsit_inc_conn_usage_count(conn);
4708 
4709 			spin_unlock_bh(&sess->conn_lock);
4710 			iscsit_cause_connection_reinstatement(conn, 1);
4711 			spin_lock_bh(&sess->conn_lock);
4712 
4713 			iscsit_dec_conn_usage_count(conn);
4714 			if (is_last == 0)
4715 				iscsit_dec_conn_usage_count(conn_tmp);
4716 			conn_count--;
4717 		}
4718 	} else {
4719 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4720 			iscsit_cause_connection_reinstatement(conn, 0);
4721 	}
4722 
4723 	if (session_sleep && atomic_read(&sess->nconn)) {
4724 		spin_unlock_bh(&sess->conn_lock);
4725 		wait_for_completion(&sess->session_wait_comp);
4726 	} else
4727 		spin_unlock_bh(&sess->conn_lock);
4728 }
4729 
iscsit_release_sessions_for_tpg(struct iscsi_portal_group * tpg,int force)4730 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4731 {
4732 	struct iscsit_session *sess;
4733 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4734 	struct se_session *se_sess, *se_sess_tmp;
4735 	LIST_HEAD(free_list);
4736 	int session_count = 0;
4737 
4738 	spin_lock_bh(&se_tpg->session_lock);
4739 	if (tpg->nsessions && !force) {
4740 		spin_unlock_bh(&se_tpg->session_lock);
4741 		return -1;
4742 	}
4743 
4744 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4745 			sess_list) {
4746 		sess = (struct iscsit_session *)se_sess->fabric_sess_ptr;
4747 
4748 		spin_lock(&sess->conn_lock);
4749 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4750 		    atomic_read(&sess->session_logout) ||
4751 		    atomic_read(&sess->session_close) ||
4752 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4753 			spin_unlock(&sess->conn_lock);
4754 			continue;
4755 		}
4756 		iscsit_inc_session_usage_count(sess);
4757 		atomic_set(&sess->session_reinstatement, 1);
4758 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4759 		atomic_set(&sess->session_close, 1);
4760 		spin_unlock(&sess->conn_lock);
4761 
4762 		list_move_tail(&se_sess->sess_list, &free_list);
4763 	}
4764 	spin_unlock_bh(&se_tpg->session_lock);
4765 
4766 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4767 		sess = (struct iscsit_session *)se_sess->fabric_sess_ptr;
4768 
4769 		list_del_init(&se_sess->sess_list);
4770 		iscsit_stop_session(sess, 1, 1);
4771 		iscsit_dec_session_usage_count(sess);
4772 		session_count++;
4773 	}
4774 
4775 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4776 			" Group: %hu\n", session_count, tpg->tpgt);
4777 	return 0;
4778 }
4779 
4780 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4781 MODULE_VERSION("4.1.x");
4782 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4783 MODULE_LICENSE("GPL");
4784 
4785 module_init(iscsi_target_init_module);
4786 module_exit(iscsi_target_cleanup_module);
4787