xref: /linux/drivers/target/iscsi/iscsi_target.c (revision 0d9ff90a5422cc7509258aaaba1e7481df4d332a)
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 				target_complete_cmd(se_cmd, SAM_STAT_TASK_ABORTED);
1539 			}
1540 
1541 			return iscsit_dump_data_payload(conn, payload_length, 1);
1542 		}
1543 	}
1544 	/*
1545 	 * Perform DataSN, DataSequenceInOrder, DataPDUInOrder, and
1546 	 * within-command recovery checks before receiving the payload.
1547 	 */
1548 	rc = iscsit_check_pre_dataout(cmd, buf);
1549 	if (rc == DATAOUT_WITHIN_COMMAND_RECOVERY)
1550 		return 0;
1551 	else if (rc == DATAOUT_CANNOT_RECOVER)
1552 		return -1;
1553 	*success = true;
1554 	return 0;
1555 }
1556 EXPORT_SYMBOL(__iscsit_check_dataout_hdr);
1557 
1558 int
iscsit_check_dataout_hdr(struct iscsit_conn * conn,void * buf,struct iscsit_cmd ** out_cmd)1559 iscsit_check_dataout_hdr(struct iscsit_conn *conn, void *buf,
1560 			 struct iscsit_cmd **out_cmd)
1561 {
1562 	struct iscsi_data *hdr = buf;
1563 	struct iscsit_cmd *cmd;
1564 	u32 payload_length = ntoh24(hdr->dlength);
1565 	int rc;
1566 	bool success = false;
1567 
1568 	if (!payload_length) {
1569 		pr_warn_ratelimited("DataOUT payload is ZERO, ignoring.\n");
1570 		return 0;
1571 	}
1572 
1573 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1574 		pr_err_ratelimited("DataSegmentLength: %u is greater than"
1575 			" MaxXmitDataSegmentLength: %u\n", payload_length,
1576 			conn->conn_ops->MaxXmitDataSegmentLength);
1577 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR, buf);
1578 	}
1579 
1580 	cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, payload_length);
1581 	if (!cmd)
1582 		return 0;
1583 
1584 	rc = __iscsit_check_dataout_hdr(conn, buf, cmd, payload_length, &success);
1585 
1586 	if (success)
1587 		*out_cmd = cmd;
1588 
1589 	return rc;
1590 }
1591 EXPORT_SYMBOL(iscsit_check_dataout_hdr);
1592 
1593 static int
iscsit_get_dataout(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_data * hdr)1594 iscsit_get_dataout(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1595 		   struct iscsi_data *hdr)
1596 {
1597 	struct kvec *iov;
1598 	u32 checksum, iov_count = 0, padding = 0, rx_got = 0, rx_size = 0;
1599 	u32 payload_length;
1600 	int iov_ret, data_crc_failed = 0;
1601 
1602 	payload_length = min_t(u32, cmd->se_cmd.data_length,
1603 			       ntoh24(hdr->dlength));
1604 	rx_size += payload_length;
1605 	iov = &cmd->iov_data[0];
1606 
1607 	iov_ret = iscsit_map_iovec(cmd, iov, cmd->orig_iov_data_count - 2,
1608 				   be32_to_cpu(hdr->offset), payload_length);
1609 	if (iov_ret < 0)
1610 		return -1;
1611 
1612 	iov_count += iov_ret;
1613 
1614 	padding = ((-payload_length) & 3);
1615 	if (padding != 0) {
1616 		iov[iov_count].iov_base	= cmd->pad_bytes;
1617 		iov[iov_count++].iov_len = padding;
1618 		rx_size += padding;
1619 		pr_debug("Receiving %u padding bytes.\n", padding);
1620 	}
1621 
1622 	if (conn->conn_ops->DataDigest) {
1623 		iov[iov_count].iov_base = &checksum;
1624 		iov[iov_count++].iov_len = ISCSI_CRC_LEN;
1625 		rx_size += ISCSI_CRC_LEN;
1626 	}
1627 
1628 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
1629 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
1630 
1631 	iscsit_unmap_iovec(cmd);
1632 
1633 	if (rx_got != rx_size)
1634 		return -1;
1635 
1636 	if (conn->conn_ops->DataDigest) {
1637 		u32 data_crc;
1638 
1639 		data_crc = iscsit_crc_sglist(cmd, payload_length, padding,
1640 					     cmd->pad_bytes);
1641 		if (checksum != data_crc) {
1642 			pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1643 				" DataSN: 0x%08x, CRC32C DataDigest 0x%08x"
1644 				" does not match computed 0x%08x\n",
1645 				hdr->itt, hdr->offset, payload_length,
1646 				hdr->datasn, checksum, data_crc);
1647 			data_crc_failed = 1;
1648 		} else {
1649 			pr_debug("Got CRC32C DataDigest 0x%08x for"
1650 				" %u bytes of Data Out\n", checksum,
1651 				payload_length);
1652 		}
1653 	}
1654 
1655 	return data_crc_failed;
1656 }
1657 
1658 int
iscsit_check_dataout_payload(struct iscsit_cmd * cmd,struct iscsi_data * hdr,bool data_crc_failed)1659 iscsit_check_dataout_payload(struct iscsit_cmd *cmd, struct iscsi_data *hdr,
1660 			     bool data_crc_failed)
1661 {
1662 	struct iscsit_conn *conn = cmd->conn;
1663 	int rc, ooo_cmdsn;
1664 	/*
1665 	 * Increment post receive data and CRC values or perform
1666 	 * within-command recovery.
1667 	 */
1668 	rc = iscsit_check_post_dataout(cmd, (unsigned char *)hdr, data_crc_failed);
1669 	if ((rc == DATAOUT_NORMAL) || (rc == DATAOUT_WITHIN_COMMAND_RECOVERY))
1670 		return 0;
1671 	else if (rc == DATAOUT_SEND_R2T) {
1672 		iscsit_set_dataout_sequence_values(cmd);
1673 		conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
1674 	} else if (rc == DATAOUT_SEND_TO_TRANSPORT) {
1675 		/*
1676 		 * Handle extra special case for out of order
1677 		 * Unsolicited Data Out.
1678 		 */
1679 		spin_lock_bh(&cmd->istate_lock);
1680 		ooo_cmdsn = (cmd->cmd_flags & ICF_OOO_CMDSN);
1681 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
1682 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
1683 		spin_unlock_bh(&cmd->istate_lock);
1684 
1685 		iscsit_stop_dataout_timer(cmd);
1686 		if (ooo_cmdsn)
1687 			return 0;
1688 		target_execute_cmd(&cmd->se_cmd);
1689 		return 0;
1690 	} else /* DATAOUT_CANNOT_RECOVER */
1691 		return -1;
1692 
1693 	return 0;
1694 }
1695 EXPORT_SYMBOL(iscsit_check_dataout_payload);
1696 
iscsit_handle_data_out(struct iscsit_conn * conn,unsigned char * buf)1697 static int iscsit_handle_data_out(struct iscsit_conn *conn, unsigned char *buf)
1698 {
1699 	struct iscsit_cmd *cmd = NULL;
1700 	struct iscsi_data *hdr = (struct iscsi_data *)buf;
1701 	int rc;
1702 	bool data_crc_failed = false;
1703 
1704 	rc = iscsit_check_dataout_hdr(conn, buf, &cmd);
1705 	if (rc < 0)
1706 		return 0;
1707 	else if (!cmd)
1708 		return 0;
1709 
1710 	rc = iscsit_get_dataout(conn, cmd, hdr);
1711 	if (rc < 0)
1712 		return rc;
1713 	else if (rc > 0)
1714 		data_crc_failed = true;
1715 
1716 	return iscsit_check_dataout_payload(cmd, hdr, data_crc_failed);
1717 }
1718 
iscsit_setup_nop_out(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_nopout * hdr)1719 int iscsit_setup_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1720 			 struct iscsi_nopout *hdr)
1721 {
1722 	u32 payload_length = ntoh24(hdr->dlength);
1723 
1724 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL)) {
1725 		pr_err("NopOUT Flag's, Left Most Bit not set, protocol error.\n");
1726 		if (!cmd)
1727 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1728 						 (unsigned char *)hdr);
1729 
1730 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1731 					 (unsigned char *)hdr);
1732 	}
1733 
1734 	if (hdr->itt == RESERVED_ITT && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
1735 		pr_err("NOPOUT ITT is reserved, but Immediate Bit is"
1736 			" not set, protocol error.\n");
1737 		if (!cmd)
1738 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1739 						 (unsigned char *)hdr);
1740 
1741 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1742 					 (unsigned char *)hdr);
1743 	}
1744 
1745 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
1746 		pr_err("NOPOUT Ping Data DataSegmentLength: %u is"
1747 			" greater than MaxXmitDataSegmentLength: %u, protocol"
1748 			" error.\n", payload_length,
1749 			conn->conn_ops->MaxXmitDataSegmentLength);
1750 		if (!cmd)
1751 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1752 						 (unsigned char *)hdr);
1753 
1754 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1755 					 (unsigned char *)hdr);
1756 	}
1757 
1758 	pr_debug("Got NOPOUT Ping %s ITT: 0x%08x, TTT: 0x%08x,"
1759 		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, Length: %u\n",
1760 		hdr->itt == RESERVED_ITT ? "Response" : "Request",
1761 		hdr->itt, hdr->ttt, hdr->cmdsn, hdr->exp_statsn,
1762 		payload_length);
1763 	/*
1764 	 * This is not a response to a Unsolicited NopIN, which means
1765 	 * it can either be a NOPOUT ping request (with a valid ITT),
1766 	 * or a NOPOUT not requesting a NOPIN (with a reserved ITT).
1767 	 * Either way, make sure we allocate an struct iscsit_cmd, as both
1768 	 * can contain ping data.
1769 	 */
1770 	if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1771 		cmd->iscsi_opcode	= ISCSI_OP_NOOP_OUT;
1772 		cmd->i_state		= ISTATE_SEND_NOPIN;
1773 		cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ?
1774 						1 : 0);
1775 		conn->sess->init_task_tag = cmd->init_task_tag = hdr->itt;
1776 		cmd->targ_xfer_tag	= 0xFFFFFFFF;
1777 		cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
1778 		cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
1779 		cmd->data_direction	= DMA_NONE;
1780 	}
1781 
1782 	return 0;
1783 }
1784 EXPORT_SYMBOL(iscsit_setup_nop_out);
1785 
iscsit_process_nop_out(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_nopout * hdr)1786 int iscsit_process_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1787 			   struct iscsi_nopout *hdr)
1788 {
1789 	struct iscsit_cmd *cmd_p = NULL;
1790 	int cmdsn_ret = 0;
1791 	/*
1792 	 * Initiator is expecting a NopIN ping reply..
1793 	 */
1794 	if (hdr->itt != RESERVED_ITT) {
1795 		if (!cmd)
1796 			return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1797 						(unsigned char *)hdr);
1798 
1799 		spin_lock_bh(&conn->cmd_lock);
1800 		list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
1801 		spin_unlock_bh(&conn->cmd_lock);
1802 
1803 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
1804 
1805 		if (hdr->opcode & ISCSI_OP_IMMEDIATE) {
1806 			iscsit_add_cmd_to_response_queue(cmd, conn,
1807 							 cmd->i_state);
1808 			return 0;
1809 		}
1810 
1811 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
1812 				(unsigned char *)hdr, hdr->cmdsn);
1813                 if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
1814 			return 0;
1815 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
1816 			return -1;
1817 
1818 		return 0;
1819 	}
1820 	/*
1821 	 * This was a response to a unsolicited NOPIN ping.
1822 	 */
1823 	if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1824 		cmd_p = iscsit_find_cmd_from_ttt(conn, be32_to_cpu(hdr->ttt));
1825 		if (!cmd_p)
1826 			return -EINVAL;
1827 
1828 		iscsit_stop_nopin_response_timer(conn);
1829 
1830 		cmd_p->i_state = ISTATE_REMOVE;
1831 		iscsit_add_cmd_to_immediate_queue(cmd_p, conn, cmd_p->i_state);
1832 
1833 		iscsit_start_nopin_timer(conn);
1834 		return 0;
1835 	}
1836 	/*
1837 	 * Otherwise, initiator is not expecting a NOPIN is response.
1838 	 * Just ignore for now.
1839 	 */
1840 
1841 	if (cmd)
1842 		iscsit_free_cmd(cmd, false);
1843 
1844         return 0;
1845 }
1846 EXPORT_SYMBOL(iscsit_process_nop_out);
1847 
iscsit_handle_nop_out(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)1848 static int iscsit_handle_nop_out(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1849 				 unsigned char *buf)
1850 {
1851 	unsigned char *ping_data = NULL;
1852 	struct iscsi_nopout *hdr = (struct iscsi_nopout *)buf;
1853 	struct kvec *iov = NULL;
1854 	u32 payload_length = ntoh24(hdr->dlength);
1855 	int ret;
1856 
1857 	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1858 	if (ret < 0)
1859 		return 0;
1860 	/*
1861 	 * Handle NOP-OUT payload for traditional iSCSI sockets
1862 	 */
1863 	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1864 		u32 checksum, data_crc, padding = 0;
1865 		int niov = 0, rx_got, rx_size = payload_length;
1866 
1867 		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1868 		if (!ping_data) {
1869 			ret = -1;
1870 			goto out;
1871 		}
1872 
1873 		iov = &cmd->iov_misc[0];
1874 		iov[niov].iov_base	= ping_data;
1875 		iov[niov++].iov_len	= payload_length;
1876 
1877 		padding = ((-payload_length) & 3);
1878 		if (padding != 0) {
1879 			pr_debug("Receiving %u additional bytes"
1880 				" for padding.\n", padding);
1881 			iov[niov].iov_base	= &cmd->pad_bytes;
1882 			iov[niov++].iov_len	= padding;
1883 			rx_size += padding;
1884 		}
1885 		if (conn->conn_ops->DataDigest) {
1886 			iov[niov].iov_base	= &checksum;
1887 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
1888 			rx_size += ISCSI_CRC_LEN;
1889 		}
1890 
1891 		WARN_ON_ONCE(niov > ARRAY_SIZE(cmd->iov_misc));
1892 		rx_got = rx_data(conn, &cmd->iov_misc[0], niov, rx_size);
1893 		if (rx_got != rx_size) {
1894 			ret = -1;
1895 			goto out;
1896 		}
1897 
1898 		if (conn->conn_ops->DataDigest) {
1899 			data_crc = iscsit_crc_buf(ping_data, payload_length,
1900 						  padding, cmd->pad_bytes);
1901 			if (checksum != data_crc) {
1902 				pr_err("Ping data CRC32C DataDigest"
1903 				" 0x%08x does not match computed 0x%08x\n",
1904 					checksum, data_crc);
1905 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1906 					pr_err("Unable to recover from"
1907 					" NOPOUT Ping DataCRC failure while in"
1908 						" ERL=0.\n");
1909 					ret = -1;
1910 					goto out;
1911 				} else {
1912 					/*
1913 					 * Silently drop this PDU and let the
1914 					 * initiator plug the CmdSN gap.
1915 					 */
1916 					pr_debug("Dropping NOPOUT"
1917 					" Command CmdSN: 0x%08x due to"
1918 					" DataCRC error.\n", hdr->cmdsn);
1919 					ret = 0;
1920 					goto out;
1921 				}
1922 			} else {
1923 				pr_debug("Got CRC32C DataDigest"
1924 				" 0x%08x for %u bytes of ping data.\n",
1925 					checksum, payload_length);
1926 			}
1927 		}
1928 
1929 		ping_data[payload_length] = '\0';
1930 		/*
1931 		 * Attach ping data to struct iscsit_cmd->buf_ptr.
1932 		 */
1933 		cmd->buf_ptr = ping_data;
1934 		cmd->buf_ptr_size = payload_length;
1935 
1936 		pr_debug("Got %u bytes of NOPOUT ping"
1937 			" data.\n", payload_length);
1938 		pr_debug("Ping Data: \"%s\"\n", ping_data);
1939 	}
1940 
1941 	return iscsit_process_nop_out(conn, cmd, hdr);
1942 out:
1943 	if (cmd)
1944 		iscsit_free_cmd(cmd, false);
1945 
1946 	kfree(ping_data);
1947 	return ret;
1948 }
1949 
iscsit_convert_tmf(u8 iscsi_tmf)1950 static enum tcm_tmreq_table iscsit_convert_tmf(u8 iscsi_tmf)
1951 {
1952 	switch (iscsi_tmf) {
1953 	case ISCSI_TM_FUNC_ABORT_TASK:
1954 		return TMR_ABORT_TASK;
1955 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
1956 		return TMR_ABORT_TASK_SET;
1957 	case ISCSI_TM_FUNC_CLEAR_ACA:
1958 		return TMR_CLEAR_ACA;
1959 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
1960 		return TMR_CLEAR_TASK_SET;
1961 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
1962 		return TMR_LUN_RESET;
1963 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
1964 		return TMR_TARGET_WARM_RESET;
1965 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
1966 		return TMR_TARGET_COLD_RESET;
1967 	default:
1968 		return TMR_UNKNOWN;
1969 	}
1970 }
1971 
1972 int
iscsit_handle_task_mgt_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)1973 iscsit_handle_task_mgt_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
1974 			   unsigned char *buf)
1975 {
1976 	struct se_tmr_req *se_tmr;
1977 	struct iscsi_tmr_req *tmr_req;
1978 	struct iscsi_tm *hdr;
1979 	int out_of_order_cmdsn = 0, ret;
1980 	u8 function, tcm_function = TMR_UNKNOWN;
1981 
1982 	hdr			= (struct iscsi_tm *) buf;
1983 	hdr->flags &= ~ISCSI_FLAG_CMD_FINAL;
1984 	function = hdr->flags;
1985 
1986 	pr_debug("Got Task Management Request ITT: 0x%08x, CmdSN:"
1987 		" 0x%08x, Function: 0x%02x, RefTaskTag: 0x%08x, RefCmdSN:"
1988 		" 0x%08x, CID: %hu\n", hdr->itt, hdr->cmdsn, function,
1989 		hdr->rtt, hdr->refcmdsn, conn->cid);
1990 
1991 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
1992 	    ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
1993 	     hdr->rtt != RESERVED_ITT)) {
1994 		pr_err("RefTaskTag should be set to 0xFFFFFFFF.\n");
1995 		hdr->rtt = RESERVED_ITT;
1996 	}
1997 
1998 	if ((function == ISCSI_TM_FUNC_TASK_REASSIGN) &&
1999 			!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2000 		pr_err("Task Management Request TASK_REASSIGN not"
2001 			" issued as immediate command, bad iSCSI Initiator"
2002 				"implementation\n");
2003 		return iscsit_add_reject_cmd(cmd,
2004 					     ISCSI_REASON_PROTOCOL_ERROR, buf);
2005 	}
2006 	if ((function != ISCSI_TM_FUNC_ABORT_TASK) &&
2007 	    be32_to_cpu(hdr->refcmdsn) != ISCSI_RESERVED_TAG)
2008 		hdr->refcmdsn = cpu_to_be32(ISCSI_RESERVED_TAG);
2009 
2010 	cmd->data_direction = DMA_NONE;
2011 	cmd->tmr_req = kzalloc_obj(*cmd->tmr_req);
2012 	if (!cmd->tmr_req) {
2013 		return iscsit_add_reject_cmd(cmd,
2014 					     ISCSI_REASON_BOOKMARK_NO_RESOURCES,
2015 					     buf);
2016 	}
2017 
2018 	__target_init_cmd(&cmd->se_cmd, &iscsi_ops,
2019 			  conn->sess->se_sess, 0, DMA_NONE,
2020 			  TCM_SIMPLE_TAG, cmd->sense_buffer + 2,
2021 			  scsilun_to_int(&hdr->lun),
2022 			  conn->cmd_cnt);
2023 
2024 	target_get_sess_cmd(&cmd->se_cmd, true);
2025 
2026 	/*
2027 	 * TASK_REASSIGN for ERL=2 / connection stays inside of
2028 	 * LIO-Target $FABRIC_MOD
2029 	 */
2030 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2031 		tcm_function = iscsit_convert_tmf(function);
2032 		if (tcm_function == TMR_UNKNOWN) {
2033 			pr_err("Unknown iSCSI TMR Function:"
2034 			       " 0x%02x\n", function);
2035 			return iscsit_add_reject_cmd(cmd,
2036 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2037 		}
2038 	}
2039 	ret = core_tmr_alloc_req(&cmd->se_cmd, cmd->tmr_req, tcm_function,
2040 				 GFP_KERNEL);
2041 	if (ret < 0)
2042 		return iscsit_add_reject_cmd(cmd,
2043 				ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
2044 
2045 	cmd->tmr_req->se_tmr_req = cmd->se_cmd.se_tmr_req;
2046 
2047 	cmd->iscsi_opcode	= ISCSI_OP_SCSI_TMFUNC;
2048 	cmd->i_state		= ISTATE_SEND_TASKMGTRSP;
2049 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2050 	cmd->init_task_tag	= hdr->itt;
2051 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2052 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2053 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2054 	se_tmr			= cmd->se_cmd.se_tmr_req;
2055 	tmr_req			= cmd->tmr_req;
2056 	/*
2057 	 * Locate the struct se_lun for all TMRs not related to ERL=2 TASK_REASSIGN
2058 	 */
2059 	if (function != ISCSI_TM_FUNC_TASK_REASSIGN) {
2060 		ret = transport_lookup_tmr_lun(&cmd->se_cmd);
2061 		if (ret < 0) {
2062 			se_tmr->response = ISCSI_TMF_RSP_NO_LUN;
2063 			goto attach;
2064 		}
2065 	}
2066 
2067 	switch (function) {
2068 	case ISCSI_TM_FUNC_ABORT_TASK:
2069 		se_tmr->response = iscsit_tmr_abort_task(cmd, buf);
2070 		if (se_tmr->response)
2071 			goto attach;
2072 		break;
2073 	case ISCSI_TM_FUNC_ABORT_TASK_SET:
2074 	case ISCSI_TM_FUNC_CLEAR_ACA:
2075 	case ISCSI_TM_FUNC_CLEAR_TASK_SET:
2076 	case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET:
2077 		break;
2078 	case ISCSI_TM_FUNC_TARGET_WARM_RESET:
2079 		if (iscsit_tmr_task_warm_reset(conn, tmr_req, buf) < 0) {
2080 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2081 			goto attach;
2082 		}
2083 		break;
2084 	case ISCSI_TM_FUNC_TARGET_COLD_RESET:
2085 		if (iscsit_tmr_task_cold_reset(conn, tmr_req, buf) < 0) {
2086 			se_tmr->response = ISCSI_TMF_RSP_AUTH_FAILED;
2087 			goto attach;
2088 		}
2089 		break;
2090 	case ISCSI_TM_FUNC_TASK_REASSIGN:
2091 		se_tmr->response = iscsit_tmr_task_reassign(cmd, buf);
2092 		/*
2093 		 * Perform sanity checks on the ExpDataSN only if the
2094 		 * TASK_REASSIGN was successful.
2095 		 */
2096 		if (se_tmr->response)
2097 			break;
2098 
2099 		if (iscsit_check_task_reassign_expdatasn(tmr_req, conn) < 0)
2100 			return iscsit_add_reject_cmd(cmd,
2101 					ISCSI_REASON_BOOKMARK_INVALID, buf);
2102 		break;
2103 	default:
2104 		pr_err("Unknown TMR function: 0x%02x, protocol"
2105 			" error.\n", function);
2106 		se_tmr->response = ISCSI_TMF_RSP_NOT_SUPPORTED;
2107 		goto attach;
2108 	}
2109 
2110 	if ((function != ISCSI_TM_FUNC_TASK_REASSIGN) &&
2111 	    (se_tmr->response == ISCSI_TMF_RSP_COMPLETE))
2112 		se_tmr->call_transport = 1;
2113 attach:
2114 	spin_lock_bh(&conn->cmd_lock);
2115 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2116 	spin_unlock_bh(&conn->cmd_lock);
2117 
2118 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2119 		int cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2120 		if (cmdsn_ret == CMDSN_HIGHER_THAN_EXP) {
2121 			out_of_order_cmdsn = 1;
2122 		} else if (cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
2123 			target_put_sess_cmd(&cmd->se_cmd);
2124 			return 0;
2125 		} else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER) {
2126 			return -1;
2127 		}
2128 	}
2129 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2130 
2131 	if (out_of_order_cmdsn || !(hdr->opcode & ISCSI_OP_IMMEDIATE))
2132 		return 0;
2133 	/*
2134 	 * Found the referenced task, send to transport for processing.
2135 	 */
2136 	if (se_tmr->call_transport)
2137 		return transport_generic_handle_tmr(&cmd->se_cmd);
2138 
2139 	/*
2140 	 * Could not find the referenced LUN, task, or Task Management
2141 	 * command not authorized or supported.  Change state and
2142 	 * let the tx_thread send the response.
2143 	 *
2144 	 * For connection recovery, this is also the default action for
2145 	 * TMR TASK_REASSIGN.
2146 	 */
2147 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2148 	target_put_sess_cmd(&cmd->se_cmd);
2149 	return 0;
2150 }
2151 EXPORT_SYMBOL(iscsit_handle_task_mgt_cmd);
2152 
2153 /* #warning FIXME: Support Text Command parameters besides SendTargets */
2154 int
iscsit_setup_text_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_text * hdr)2155 iscsit_setup_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2156 		      struct iscsi_text *hdr)
2157 {
2158 	u32 payload_length = ntoh24(hdr->dlength);
2159 
2160 	if (payload_length > conn->conn_ops->MaxXmitDataSegmentLength) {
2161 		pr_err("Unable to accept text parameter length: %u"
2162 			"greater than MaxXmitDataSegmentLength %u.\n",
2163 		       payload_length, conn->conn_ops->MaxXmitDataSegmentLength);
2164 		return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2165 					 (unsigned char *)hdr);
2166 	}
2167 
2168 	if (!(hdr->flags & ISCSI_FLAG_CMD_FINAL) ||
2169 	     (hdr->flags & ISCSI_FLAG_TEXT_CONTINUE)) {
2170 		pr_err("Multi sequence text commands currently not supported\n");
2171 		return iscsit_reject_cmd(cmd, ISCSI_REASON_CMD_NOT_SUPPORTED,
2172 					(unsigned char *)hdr);
2173 	}
2174 
2175 	pr_debug("Got Text Request: ITT: 0x%08x, CmdSN: 0x%08x,"
2176 		" ExpStatSN: 0x%08x, Length: %u\n", hdr->itt, hdr->cmdsn,
2177 		hdr->exp_statsn, payload_length);
2178 
2179 	cmd->iscsi_opcode	= ISCSI_OP_TEXT;
2180 	cmd->i_state		= ISTATE_SEND_TEXTRSP;
2181 	cmd->immediate_cmd	= ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2182 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2183 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2184 	cmd->cmd_sn		= be32_to_cpu(hdr->cmdsn);
2185 	cmd->exp_stat_sn	= be32_to_cpu(hdr->exp_statsn);
2186 	cmd->data_direction	= DMA_NONE;
2187 	kfree(cmd->text_in_ptr);
2188 	cmd->text_in_ptr	= NULL;
2189 
2190 	return 0;
2191 }
2192 EXPORT_SYMBOL(iscsit_setup_text_cmd);
2193 
2194 int
iscsit_process_text_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,struct iscsi_text * hdr)2195 iscsit_process_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2196 			struct iscsi_text *hdr)
2197 {
2198 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr;
2199 	int cmdsn_ret;
2200 
2201 	if (!text_in) {
2202 		cmd->targ_xfer_tag = be32_to_cpu(hdr->ttt);
2203 		if (cmd->targ_xfer_tag == 0xFFFFFFFF) {
2204 			pr_err("Unable to locate text_in buffer for sendtargets"
2205 			       " discovery\n");
2206 			goto reject;
2207 		}
2208 		goto empty_sendtargets;
2209 	}
2210 	if (strncmp("SendTargets=", text_in, 12) != 0) {
2211 		pr_err("Received Text Data that is not"
2212 			" SendTargets, cannot continue.\n");
2213 		goto reject;
2214 	}
2215 	/* '=' confirmed in strncmp */
2216 	text_ptr = strchr(text_in, '=');
2217 	BUG_ON(!text_ptr);
2218 	if (!strncmp("=All", text_ptr, 5)) {
2219 		cmd->cmd_flags |= ICF_SENDTARGETS_ALL;
2220 	} else if (!strncmp("=iqn.", text_ptr, 5) ||
2221 		   !strncmp("=eui.", text_ptr, 5)) {
2222 		cmd->cmd_flags |= ICF_SENDTARGETS_SINGLE;
2223 	} else {
2224 		pr_err("Unable to locate valid SendTargets%s value\n",
2225 		       text_ptr);
2226 		goto reject;
2227 	}
2228 
2229 	spin_lock_bh(&conn->cmd_lock);
2230 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2231 	spin_unlock_bh(&conn->cmd_lock);
2232 
2233 empty_sendtargets:
2234 	iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2235 
2236 	if (!(hdr->opcode & ISCSI_OP_IMMEDIATE)) {
2237 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
2238 				(unsigned char *)hdr, hdr->cmdsn);
2239 		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2240 			return -1;
2241 
2242 		return 0;
2243 	}
2244 
2245 	return iscsit_execute_cmd(cmd, 0);
2246 
2247 reject:
2248 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
2249 				 (unsigned char *)hdr);
2250 }
2251 EXPORT_SYMBOL(iscsit_process_text_cmd);
2252 
2253 static int
iscsit_handle_text_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)2254 iscsit_handle_text_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2255 		       unsigned char *buf)
2256 {
2257 	struct iscsi_text *hdr = (struct iscsi_text *)buf;
2258 	char *text_in = NULL;
2259 	u32 payload_length = ntoh24(hdr->dlength);
2260 	int rx_size, rc;
2261 
2262 	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
2263 	if (rc < 0)
2264 		return 0;
2265 
2266 	rx_size = payload_length;
2267 	if (payload_length) {
2268 		u32 checksum = 0, data_crc = 0;
2269 		u32 padding = 0;
2270 		int niov = 0, rx_got;
2271 		struct kvec iov[2];
2272 
2273 		rx_size = ALIGN(payload_length, 4);
2274 		text_in = kzalloc(rx_size, GFP_KERNEL);
2275 		if (!text_in)
2276 			goto reject;
2277 
2278 		cmd->text_in_ptr = text_in;
2279 
2280 		memset(iov, 0, sizeof(iov));
2281 		iov[niov].iov_base	= text_in;
2282 		iov[niov++].iov_len	= rx_size;
2283 
2284 		padding = rx_size - payload_length;
2285 		if (padding)
2286 			pr_debug("Receiving %u additional bytes"
2287 					" for padding.\n", padding);
2288 		if (conn->conn_ops->DataDigest) {
2289 			iov[niov].iov_base	= &checksum;
2290 			iov[niov++].iov_len	= ISCSI_CRC_LEN;
2291 			rx_size += ISCSI_CRC_LEN;
2292 		}
2293 
2294 		WARN_ON_ONCE(niov > ARRAY_SIZE(iov));
2295 		rx_got = rx_data(conn, &iov[0], niov, rx_size);
2296 		if (rx_got != rx_size)
2297 			goto reject;
2298 
2299 		if (conn->conn_ops->DataDigest) {
2300 			data_crc = iscsit_crc_buf(text_in,
2301 						  ALIGN(payload_length, 4),
2302 						  0, NULL);
2303 			if (checksum != data_crc) {
2304 				pr_err("Text data CRC32C DataDigest"
2305 					" 0x%08x does not match computed"
2306 					" 0x%08x\n", checksum, data_crc);
2307 				if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2308 					pr_err("Unable to recover from"
2309 					" Text Data digest failure while in"
2310 						" ERL=0.\n");
2311 					goto reject;
2312 				} else {
2313 					/*
2314 					 * Silently drop this PDU and let the
2315 					 * initiator plug the CmdSN gap.
2316 					 */
2317 					pr_debug("Dropping Text"
2318 					" Command CmdSN: 0x%08x due to"
2319 					" DataCRC error.\n", hdr->cmdsn);
2320 					kfree(text_in);
2321 					cmd->text_in_ptr = NULL;
2322 					return 0;
2323 				}
2324 			} else {
2325 				pr_debug("Got CRC32C DataDigest"
2326 					" 0x%08x for %u bytes of text data.\n",
2327 						checksum, payload_length);
2328 			}
2329 		}
2330 		text_in[payload_length - 1] = '\0';
2331 		pr_debug("Successfully read %d bytes of text"
2332 				" data.\n", payload_length);
2333 	}
2334 
2335 	return iscsit_process_text_cmd(conn, cmd, hdr);
2336 
2337 reject:
2338 	kfree(cmd->text_in_ptr);
2339 	cmd->text_in_ptr = NULL;
2340 	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
2341 }
2342 
iscsit_logout_closesession(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2343 int iscsit_logout_closesession(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2344 {
2345 	struct iscsit_conn *conn_p;
2346 	struct iscsit_session *sess = conn->sess;
2347 
2348 	pr_debug("Received logout request CLOSESESSION on CID: %hu"
2349 		" for SID: %u.\n", conn->cid, conn->sess->sid);
2350 
2351 	atomic_set(&sess->session_logout, 1);
2352 	atomic_set(&conn->conn_logout_remove, 1);
2353 	conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_SESSION;
2354 
2355 	iscsit_inc_conn_usage_count(conn);
2356 	iscsit_inc_session_usage_count(sess);
2357 
2358 	spin_lock_bh(&sess->conn_lock);
2359 	list_for_each_entry(conn_p, &sess->sess_conn_list, conn_list) {
2360 		if (conn_p->conn_state != TARG_CONN_STATE_LOGGED_IN)
2361 			continue;
2362 
2363 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2364 		conn_p->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2365 	}
2366 	spin_unlock_bh(&sess->conn_lock);
2367 
2368 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2369 
2370 	return 0;
2371 }
2372 
iscsit_logout_closeconnection(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2373 int iscsit_logout_closeconnection(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2374 {
2375 	struct iscsit_conn *l_conn;
2376 	struct iscsit_session *sess = conn->sess;
2377 
2378 	pr_debug("Received logout request CLOSECONNECTION for CID:"
2379 		" %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2380 
2381 	/*
2382 	 * A Logout Request with a CLOSECONNECTION reason code for a CID
2383 	 * can arrive on a connection with a differing CID.
2384 	 */
2385 	if (conn->cid == cmd->logout_cid) {
2386 		spin_lock_bh(&conn->state_lock);
2387 		pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
2388 		conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
2389 
2390 		atomic_set(&conn->conn_logout_remove, 1);
2391 		conn->conn_logout_reason = ISCSI_LOGOUT_REASON_CLOSE_CONNECTION;
2392 		iscsit_inc_conn_usage_count(conn);
2393 
2394 		spin_unlock_bh(&conn->state_lock);
2395 	} else {
2396 		/*
2397 		 * Handle all different cid CLOSECONNECTION requests in
2398 		 * iscsit_logout_post_handler_diffcid() as to give enough
2399 		 * time for any non immediate command's CmdSN to be
2400 		 * acknowledged on the connection in question.
2401 		 *
2402 		 * Here we simply make sure the CID is still around.
2403 		 */
2404 		l_conn = iscsit_get_conn_from_cid(sess,
2405 				cmd->logout_cid);
2406 		if (!l_conn) {
2407 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2408 			iscsit_add_cmd_to_response_queue(cmd, conn,
2409 					cmd->i_state);
2410 			return 0;
2411 		}
2412 
2413 		iscsit_dec_conn_usage_count(l_conn);
2414 	}
2415 
2416 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2417 
2418 	return 0;
2419 }
2420 
iscsit_logout_removeconnforrecovery(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2421 int iscsit_logout_removeconnforrecovery(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2422 {
2423 	struct iscsit_session *sess = conn->sess;
2424 
2425 	pr_debug("Received explicit REMOVECONNFORRECOVERY logout for"
2426 		" CID: %hu on CID: %hu.\n", cmd->logout_cid, conn->cid);
2427 
2428 	if (sess->sess_ops->ErrorRecoveryLevel != 2) {
2429 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2430 			" while ERL!=2.\n");
2431 		cmd->logout_response = ISCSI_LOGOUT_RECOVERY_UNSUPPORTED;
2432 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2433 		return 0;
2434 	}
2435 
2436 	if (conn->cid == cmd->logout_cid) {
2437 		pr_err("Received Logout Request REMOVECONNFORRECOVERY"
2438 			" with CID: %hu on CID: %hu, implementation error.\n",
2439 				cmd->logout_cid, conn->cid);
2440 		cmd->logout_response = ISCSI_LOGOUT_CLEANUP_FAILED;
2441 		iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2442 		return 0;
2443 	}
2444 
2445 	iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
2446 
2447 	return 0;
2448 }
2449 
2450 int
iscsit_handle_logout_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,unsigned char * buf)2451 iscsit_handle_logout_cmd(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
2452 			unsigned char *buf)
2453 {
2454 	int cmdsn_ret, logout_remove = 0;
2455 	u8 reason_code = 0;
2456 	struct iscsi_logout *hdr;
2457 	struct iscsi_tiqn *tiqn = iscsit_snmp_get_tiqn(conn);
2458 
2459 	hdr			= (struct iscsi_logout *) buf;
2460 	reason_code		= (hdr->flags & 0x7f);
2461 
2462 	if (tiqn) {
2463 		spin_lock(&tiqn->logout_stats.lock);
2464 		if (reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION)
2465 			tiqn->logout_stats.normal_logouts++;
2466 		else
2467 			tiqn->logout_stats.abnormal_logouts++;
2468 		spin_unlock(&tiqn->logout_stats.lock);
2469 	}
2470 
2471 	pr_debug("Got Logout Request ITT: 0x%08x CmdSN: 0x%08x"
2472 		" ExpStatSN: 0x%08x Reason: 0x%02x CID: %hu on CID: %hu\n",
2473 		hdr->itt, hdr->cmdsn, hdr->exp_statsn, reason_code,
2474 		hdr->cid, conn->cid);
2475 
2476 	if (conn->conn_state != TARG_CONN_STATE_LOGGED_IN) {
2477 		pr_err("Received logout request on connection that"
2478 			" is not in logged in state, ignoring request.\n");
2479 		iscsit_free_cmd(cmd, false);
2480 		return 0;
2481 	}
2482 
2483 	cmd->iscsi_opcode       = ISCSI_OP_LOGOUT;
2484 	cmd->i_state            = ISTATE_SEND_LOGOUTRSP;
2485 	cmd->immediate_cmd      = ((hdr->opcode & ISCSI_OP_IMMEDIATE) ? 1 : 0);
2486 	conn->sess->init_task_tag = cmd->init_task_tag  = hdr->itt;
2487 	cmd->targ_xfer_tag      = 0xFFFFFFFF;
2488 	cmd->cmd_sn             = be32_to_cpu(hdr->cmdsn);
2489 	cmd->exp_stat_sn        = be32_to_cpu(hdr->exp_statsn);
2490 	cmd->logout_cid         = be16_to_cpu(hdr->cid);
2491 	cmd->logout_reason      = reason_code;
2492 	cmd->data_direction     = DMA_NONE;
2493 
2494 	/*
2495 	 * We need to sleep in these cases (by returning 1) until the Logout
2496 	 * Response gets sent in the tx thread.
2497 	 */
2498 	if ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_SESSION) ||
2499 	   ((reason_code == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION) &&
2500 	    be16_to_cpu(hdr->cid) == conn->cid))
2501 		logout_remove = 1;
2502 
2503 	spin_lock_bh(&conn->cmd_lock);
2504 	list_add_tail(&cmd->i_conn_node, &conn->conn_cmd_list);
2505 	spin_unlock_bh(&conn->cmd_lock);
2506 
2507 	if (reason_code != ISCSI_LOGOUT_REASON_RECOVERY)
2508 		iscsit_ack_from_expstatsn(conn, be32_to_cpu(hdr->exp_statsn));
2509 
2510 	/*
2511 	 * Immediate commands are executed, well, immediately.
2512 	 * Non-Immediate Logout Commands are executed in CmdSN order.
2513 	 */
2514 	if (cmd->immediate_cmd) {
2515 		int ret = iscsit_execute_cmd(cmd, 0);
2516 
2517 		if (ret < 0)
2518 			return ret;
2519 	} else {
2520 		cmdsn_ret = iscsit_sequence_cmd(conn, cmd, buf, hdr->cmdsn);
2521 		if (cmdsn_ret == CMDSN_LOWER_THAN_EXP)
2522 			logout_remove = 0;
2523 		else if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
2524 			return -1;
2525 	}
2526 
2527 	return logout_remove;
2528 }
2529 EXPORT_SYMBOL(iscsit_handle_logout_cmd);
2530 
iscsit_handle_snack(struct iscsit_conn * conn,unsigned char * buf)2531 int iscsit_handle_snack(
2532 	struct iscsit_conn *conn,
2533 	unsigned char *buf)
2534 {
2535 	struct iscsi_snack *hdr;
2536 
2537 	hdr			= (struct iscsi_snack *) buf;
2538 	hdr->flags		&= ~ISCSI_FLAG_CMD_FINAL;
2539 
2540 	pr_debug("Got ISCSI_INIT_SNACK, ITT: 0x%08x, ExpStatSN:"
2541 		" 0x%08x, Type: 0x%02x, BegRun: 0x%08x, RunLength: 0x%08x,"
2542 		" CID: %hu\n", hdr->itt, hdr->exp_statsn, hdr->flags,
2543 			hdr->begrun, hdr->runlength, conn->cid);
2544 
2545 	if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2546 		pr_err("Initiator sent SNACK request while in"
2547 			" ErrorRecoveryLevel=0.\n");
2548 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2549 					 buf);
2550 	}
2551 	/*
2552 	 * SNACK_DATA and SNACK_R2T are both 0,  so check which function to
2553 	 * call from inside iscsi_send_recovery_datain_or_r2t().
2554 	 */
2555 	switch (hdr->flags & ISCSI_FLAG_SNACK_TYPE_MASK) {
2556 	case 0:
2557 		return iscsit_handle_recovery_datain_or_r2t(conn, buf,
2558 			hdr->itt,
2559 			be32_to_cpu(hdr->ttt),
2560 			be32_to_cpu(hdr->begrun),
2561 			be32_to_cpu(hdr->runlength));
2562 	case ISCSI_FLAG_SNACK_TYPE_STATUS:
2563 		return iscsit_handle_status_snack(conn, hdr->itt,
2564 			be32_to_cpu(hdr->ttt),
2565 			be32_to_cpu(hdr->begrun), be32_to_cpu(hdr->runlength));
2566 	case ISCSI_FLAG_SNACK_TYPE_DATA_ACK:
2567 		return iscsit_handle_data_ack(conn, be32_to_cpu(hdr->ttt),
2568 			be32_to_cpu(hdr->begrun),
2569 			be32_to_cpu(hdr->runlength));
2570 	case ISCSI_FLAG_SNACK_TYPE_RDATA:
2571 		/* FIXME: Support R-Data SNACK */
2572 		pr_err("R-Data SNACK Not Supported.\n");
2573 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2574 					 buf);
2575 	default:
2576 		pr_err("Unknown SNACK type 0x%02x, protocol"
2577 			" error.\n", hdr->flags & 0x0f);
2578 		return iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
2579 					 buf);
2580 	}
2581 
2582 	return 0;
2583 }
2584 EXPORT_SYMBOL(iscsit_handle_snack);
2585 
iscsit_rx_thread_wait_for_tcp(struct iscsit_conn * conn)2586 static void iscsit_rx_thread_wait_for_tcp(struct iscsit_conn *conn)
2587 {
2588 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2589 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2590 		wait_for_completion_interruptible_timeout(
2591 					&conn->rx_half_close_comp,
2592 					ISCSI_RX_THREAD_TCP_TIMEOUT * HZ);
2593 	}
2594 }
2595 
iscsit_handle_immediate_data(struct iscsit_cmd * cmd,struct iscsi_scsi_req * hdr,u32 length)2596 static int iscsit_handle_immediate_data(
2597 	struct iscsit_cmd *cmd,
2598 	struct iscsi_scsi_req *hdr,
2599 	u32 length)
2600 {
2601 	int iov_ret, rx_got = 0, rx_size = 0;
2602 	u32 checksum, iov_count = 0, padding = 0;
2603 	struct iscsit_conn *conn = cmd->conn;
2604 	struct kvec *iov;
2605 	void *overflow_buf = NULL;
2606 
2607 	BUG_ON(cmd->write_data_done > cmd->se_cmd.data_length);
2608 	rx_size = min(cmd->se_cmd.data_length - cmd->write_data_done, length);
2609 	iov_ret = iscsit_map_iovec(cmd, cmd->iov_data,
2610 				   cmd->orig_iov_data_count - 2,
2611 				   cmd->write_data_done, rx_size);
2612 	if (iov_ret < 0)
2613 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2614 
2615 	iov_count = iov_ret;
2616 	iov = &cmd->iov_data[0];
2617 	if (rx_size < length) {
2618 		/*
2619 		 * Special case: length of immediate data exceeds the data
2620 		 * buffer size derived from the CDB.
2621 		 */
2622 		overflow_buf = kmalloc(length - rx_size, GFP_KERNEL);
2623 		if (!overflow_buf) {
2624 			iscsit_unmap_iovec(cmd);
2625 			return IMMEDIATE_DATA_CANNOT_RECOVER;
2626 		}
2627 		cmd->overflow_buf = overflow_buf;
2628 		iov[iov_count].iov_base = overflow_buf;
2629 		iov[iov_count].iov_len = length - rx_size;
2630 		iov_count++;
2631 		rx_size = length;
2632 	}
2633 
2634 	padding = ((-length) & 3);
2635 	if (padding != 0) {
2636 		iov[iov_count].iov_base	= cmd->pad_bytes;
2637 		iov[iov_count++].iov_len = padding;
2638 		rx_size += padding;
2639 	}
2640 
2641 	if (conn->conn_ops->DataDigest) {
2642 		iov[iov_count].iov_base		= &checksum;
2643 		iov[iov_count++].iov_len	= ISCSI_CRC_LEN;
2644 		rx_size += ISCSI_CRC_LEN;
2645 	}
2646 
2647 	WARN_ON_ONCE(iov_count > cmd->orig_iov_data_count);
2648 	rx_got = rx_data(conn, &cmd->iov_data[0], iov_count, rx_size);
2649 
2650 	iscsit_unmap_iovec(cmd);
2651 
2652 	if (rx_got != rx_size) {
2653 		iscsit_rx_thread_wait_for_tcp(conn);
2654 		return IMMEDIATE_DATA_CANNOT_RECOVER;
2655 	}
2656 
2657 	if (conn->conn_ops->DataDigest) {
2658 		u32 data_crc;
2659 
2660 		data_crc = iscsit_crc_sglist(cmd, length, padding,
2661 					     cmd->pad_bytes);
2662 		if (checksum != data_crc) {
2663 			pr_err("ImmediateData CRC32C DataDigest 0x%08x"
2664 				" does not match computed 0x%08x\n", checksum,
2665 				data_crc);
2666 
2667 			if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
2668 				pr_err("Unable to recover from"
2669 					" Immediate Data digest failure while"
2670 					" in ERL=0.\n");
2671 				iscsit_reject_cmd(cmd,
2672 						ISCSI_REASON_DATA_DIGEST_ERROR,
2673 						(unsigned char *)hdr);
2674 				return IMMEDIATE_DATA_CANNOT_RECOVER;
2675 			} else {
2676 				iscsit_reject_cmd(cmd,
2677 						ISCSI_REASON_DATA_DIGEST_ERROR,
2678 						(unsigned char *)hdr);
2679 				return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
2680 			}
2681 		} else {
2682 			pr_debug("Got CRC32C DataDigest 0x%08x for"
2683 				" %u bytes of Immediate Data\n", checksum,
2684 				length);
2685 		}
2686 	}
2687 
2688 	cmd->write_data_done += length;
2689 
2690 	if (cmd->write_data_done == cmd->se_cmd.data_length) {
2691 		spin_lock_bh(&cmd->istate_lock);
2692 		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
2693 		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
2694 		spin_unlock_bh(&cmd->istate_lock);
2695 	}
2696 
2697 	return IMMEDIATE_DATA_NORMAL_OPERATION;
2698 }
2699 
2700 /* #warning iscsi_build_conn_drop_async_message() only sends out on connections
2701 	with active network interface */
iscsit_build_conn_drop_async_message(struct iscsit_conn * conn)2702 static void iscsit_build_conn_drop_async_message(struct iscsit_conn *conn)
2703 {
2704 	struct iscsit_cmd *cmd;
2705 	struct iscsit_conn *conn_p;
2706 	bool found = false;
2707 
2708 	lockdep_assert_held(&conn->sess->conn_lock);
2709 
2710 	/*
2711 	 * Only send a Asynchronous Message on connections whos network
2712 	 * interface is still functional.
2713 	 */
2714 	list_for_each_entry(conn_p, &conn->sess->sess_conn_list, conn_list) {
2715 		if (conn_p->conn_state == TARG_CONN_STATE_LOGGED_IN) {
2716 			iscsit_inc_conn_usage_count(conn_p);
2717 			found = true;
2718 			break;
2719 		}
2720 	}
2721 
2722 	if (!found)
2723 		return;
2724 
2725 	cmd = iscsit_allocate_cmd(conn_p, TASK_RUNNING);
2726 	if (!cmd) {
2727 		iscsit_dec_conn_usage_count(conn_p);
2728 		return;
2729 	}
2730 
2731 	cmd->logout_cid = conn->cid;
2732 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2733 	cmd->i_state = ISTATE_SEND_ASYNCMSG;
2734 
2735 	spin_lock_bh(&conn_p->cmd_lock);
2736 	list_add_tail(&cmd->i_conn_node, &conn_p->conn_cmd_list);
2737 	spin_unlock_bh(&conn_p->cmd_lock);
2738 
2739 	iscsit_add_cmd_to_response_queue(cmd, conn_p, cmd->i_state);
2740 	iscsit_dec_conn_usage_count(conn_p);
2741 }
2742 
iscsit_send_conn_drop_async_message(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2743 static int iscsit_send_conn_drop_async_message(
2744 	struct iscsit_cmd *cmd,
2745 	struct iscsit_conn *conn)
2746 {
2747 	struct iscsi_async *hdr;
2748 
2749 	cmd->iscsi_opcode = ISCSI_OP_ASYNC_EVENT;
2750 
2751 	hdr			= (struct iscsi_async *) cmd->pdu;
2752 	hdr->opcode		= ISCSI_OP_ASYNC_EVENT;
2753 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
2754 	cmd->init_task_tag	= RESERVED_ITT;
2755 	cmd->targ_xfer_tag	= 0xFFFFFFFF;
2756 	put_unaligned_be64(0xFFFFFFFFFFFFFFFFULL, &hdr->rsvd4[0]);
2757 	cmd->stat_sn		= conn->stat_sn++;
2758 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2759 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2760 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2761 	hdr->async_event	= ISCSI_ASYNC_MSG_DROPPING_CONNECTION;
2762 	hdr->param1		= cpu_to_be16(cmd->logout_cid);
2763 	hdr->param2		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Wait);
2764 	hdr->param3		= cpu_to_be16(conn->sess->sess_ops->DefaultTime2Retain);
2765 
2766 	pr_debug("Sending Connection Dropped Async Message StatSN:"
2767 		" 0x%08x, for CID: %hu on CID: %hu\n", cmd->stat_sn,
2768 			cmd->logout_cid, conn->cid);
2769 
2770 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2771 }
2772 
iscsit_tx_thread_wait_for_tcp(struct iscsit_conn * conn)2773 static void iscsit_tx_thread_wait_for_tcp(struct iscsit_conn *conn)
2774 {
2775 	if ((conn->sock->sk->sk_shutdown & SEND_SHUTDOWN) ||
2776 	    (conn->sock->sk->sk_shutdown & RCV_SHUTDOWN)) {
2777 		wait_for_completion_interruptible_timeout(
2778 					&conn->tx_half_close_comp,
2779 					ISCSI_TX_THREAD_TCP_TIMEOUT * HZ);
2780 	}
2781 }
2782 
2783 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)2784 iscsit_build_datain_pdu(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2785 			struct iscsi_datain *datain, struct iscsi_data_rsp *hdr,
2786 			bool set_statsn)
2787 {
2788 	hdr->opcode		= ISCSI_OP_SCSI_DATA_IN;
2789 	hdr->flags		= datain->flags;
2790 	if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
2791 		if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
2792 			hdr->flags |= ISCSI_FLAG_DATA_OVERFLOW;
2793 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2794 		} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
2795 			hdr->flags |= ISCSI_FLAG_DATA_UNDERFLOW;
2796 			hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
2797 		}
2798 	}
2799 	hton24(hdr->dlength, datain->length);
2800 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2801 		int_to_scsilun(cmd->se_cmd.orig_fe_lun,
2802 				(struct scsi_lun *)&hdr->lun);
2803 	else
2804 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
2805 
2806 	hdr->itt		= cmd->init_task_tag;
2807 
2808 	if (hdr->flags & ISCSI_FLAG_DATA_ACK)
2809 		hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
2810 	else
2811 		hdr->ttt		= cpu_to_be32(0xFFFFFFFF);
2812 	if (set_statsn)
2813 		hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2814 	else
2815 		hdr->statsn		= cpu_to_be32(0xFFFFFFFF);
2816 
2817 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2818 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2819 	hdr->datasn		= cpu_to_be32(datain->data_sn);
2820 	hdr->offset		= cpu_to_be32(datain->offset);
2821 
2822 	pr_debug("Built DataIN ITT: 0x%08x, StatSN: 0x%08x,"
2823 		" DataSN: 0x%08x, Offset: %u, Length: %u, CID: %hu\n",
2824 		cmd->init_task_tag, ntohl(hdr->statsn), ntohl(hdr->datasn),
2825 		ntohl(hdr->offset), datain->length, conn->cid);
2826 }
2827 EXPORT_SYMBOL(iscsit_build_datain_pdu);
2828 
iscsit_send_datain(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2829 static int iscsit_send_datain(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2830 {
2831 	struct iscsi_data_rsp *hdr = (struct iscsi_data_rsp *)&cmd->pdu[0];
2832 	struct iscsi_datain datain;
2833 	struct iscsi_datain_req *dr;
2834 	int eodr = 0, ret;
2835 	bool set_statsn = false;
2836 
2837 	memset(&datain, 0, sizeof(struct iscsi_datain));
2838 	dr = iscsit_get_datain_values(cmd, &datain);
2839 	if (!dr) {
2840 		pr_err("iscsit_get_datain_values failed for ITT: 0x%08x\n",
2841 				cmd->init_task_tag);
2842 		return -1;
2843 	}
2844 	/*
2845 	 * Be paranoid and double check the logic for now.
2846 	 */
2847 	if ((datain.offset + datain.length) > cmd->se_cmd.data_length) {
2848 		pr_err("Command ITT: 0x%08x, datain.offset: %u and"
2849 			" datain.length: %u exceeds cmd->data_length: %u\n",
2850 			cmd->init_task_tag, datain.offset, datain.length,
2851 			cmd->se_cmd.data_length);
2852 		return -1;
2853 	}
2854 
2855 	atomic_long_add(datain.length, &conn->sess->tx_data_octets);
2856 	/*
2857 	 * Special case for successfully execution w/ both DATAIN
2858 	 * and Sense Data.
2859 	 */
2860 	if ((datain.flags & ISCSI_FLAG_DATA_STATUS) &&
2861 	    (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE))
2862 		datain.flags &= ~ISCSI_FLAG_DATA_STATUS;
2863 	else {
2864 		if ((dr->dr_complete == DATAIN_COMPLETE_NORMAL) ||
2865 		    (dr->dr_complete == DATAIN_COMPLETE_CONNECTION_RECOVERY)) {
2866 			iscsit_increment_maxcmdsn(cmd, conn->sess);
2867 			cmd->stat_sn = conn->stat_sn++;
2868 			set_statsn = true;
2869 		} else if (dr->dr_complete ==
2870 			   DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY)
2871 			set_statsn = true;
2872 	}
2873 
2874 	iscsit_build_datain_pdu(cmd, conn, &datain, hdr, set_statsn);
2875 
2876 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, dr, &datain, 0);
2877 	if (ret < 0)
2878 		return ret;
2879 
2880 	if (dr->dr_complete) {
2881 		eodr = (cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ?
2882 				2 : 1;
2883 		iscsit_free_datain_req(cmd, dr);
2884 	}
2885 
2886 	return eodr;
2887 }
2888 
2889 int
iscsit_build_logout_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_logout_rsp * hdr)2890 iscsit_build_logout_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2891 			struct iscsi_logout_rsp *hdr)
2892 {
2893 	struct iscsit_conn *logout_conn = NULL;
2894 	struct iscsi_conn_recovery *cr = NULL;
2895 	struct iscsit_session *sess = conn->sess;
2896 	/*
2897 	 * The actual shutting down of Sessions and/or Connections
2898 	 * for CLOSESESSION and CLOSECONNECTION Logout Requests
2899 	 * is done in scsi_logout_post_handler().
2900 	 */
2901 	switch (cmd->logout_reason) {
2902 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
2903 		pr_debug("iSCSI session logout successful, setting"
2904 			" logout response to ISCSI_LOGOUT_SUCCESS.\n");
2905 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2906 		break;
2907 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
2908 		if (cmd->logout_response == ISCSI_LOGOUT_CID_NOT_FOUND)
2909 			break;
2910 		/*
2911 		 * For CLOSECONNECTION logout requests carrying
2912 		 * a matching logout CID -> local CID, the reference
2913 		 * for the local CID will have been incremented in
2914 		 * iscsi_logout_closeconnection().
2915 		 *
2916 		 * For CLOSECONNECTION logout requests carrying
2917 		 * a different CID than the connection it arrived
2918 		 * on, the connection responding to cmd->logout_cid
2919 		 * is stopped in iscsit_logout_post_handler_diffcid().
2920 		 */
2921 
2922 		pr_debug("iSCSI CID: %hu logout on CID: %hu"
2923 			" successful.\n", cmd->logout_cid, conn->cid);
2924 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2925 		break;
2926 	case ISCSI_LOGOUT_REASON_RECOVERY:
2927 		if ((cmd->logout_response == ISCSI_LOGOUT_RECOVERY_UNSUPPORTED) ||
2928 		    (cmd->logout_response == ISCSI_LOGOUT_CLEANUP_FAILED))
2929 			break;
2930 		/*
2931 		 * If the connection is still active from our point of view
2932 		 * force connection recovery to occur.
2933 		 */
2934 		logout_conn = iscsit_get_conn_from_cid_rcfr(sess,
2935 				cmd->logout_cid);
2936 		if (logout_conn) {
2937 			iscsit_connection_reinstatement_rcfr(logout_conn);
2938 			iscsit_dec_conn_usage_count(logout_conn);
2939 		}
2940 
2941 		cr = iscsit_get_inactive_connection_recovery_entry(
2942 				conn->sess, cmd->logout_cid);
2943 		if (!cr) {
2944 			pr_err("Unable to locate CID: %hu for"
2945 			" REMOVECONNFORRECOVERY Logout Request.\n",
2946 				cmd->logout_cid);
2947 			cmd->logout_response = ISCSI_LOGOUT_CID_NOT_FOUND;
2948 			break;
2949 		}
2950 
2951 		iscsit_discard_cr_cmds_by_expstatsn(cr, cmd->exp_stat_sn);
2952 
2953 		pr_debug("iSCSI REMOVECONNFORRECOVERY logout"
2954 			" for recovery for CID: %hu on CID: %hu successful.\n",
2955 				cmd->logout_cid, conn->cid);
2956 		cmd->logout_response = ISCSI_LOGOUT_SUCCESS;
2957 		break;
2958 	default:
2959 		pr_err("Unknown cmd->logout_reason: 0x%02x\n",
2960 				cmd->logout_reason);
2961 		return -1;
2962 	}
2963 
2964 	hdr->opcode		= ISCSI_OP_LOGOUT_RSP;
2965 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
2966 	hdr->response		= cmd->logout_response;
2967 	hdr->itt		= cmd->init_task_tag;
2968 	cmd->stat_sn		= conn->stat_sn++;
2969 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
2970 
2971 	iscsit_increment_maxcmdsn(cmd, conn->sess);
2972 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
2973 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
2974 
2975 	pr_debug("Built Logout Response ITT: 0x%08x StatSN:"
2976 		" 0x%08x Response: 0x%02x CID: %hu on CID: %hu\n",
2977 		cmd->init_task_tag, cmd->stat_sn, hdr->response,
2978 		cmd->logout_cid, conn->cid);
2979 
2980 	return 0;
2981 }
2982 EXPORT_SYMBOL(iscsit_build_logout_rsp);
2983 
2984 static int
iscsit_send_logout(struct iscsit_cmd * cmd,struct iscsit_conn * conn)2985 iscsit_send_logout(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
2986 {
2987 	int rc;
2988 
2989 	rc = iscsit_build_logout_rsp(cmd, conn,
2990 			(struct iscsi_logout_rsp *)&cmd->pdu[0]);
2991 	if (rc < 0)
2992 		return rc;
2993 
2994 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
2995 }
2996 
2997 void
iscsit_build_nopin_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_nopin * hdr,bool nopout_response)2998 iscsit_build_nopin_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
2999 		       struct iscsi_nopin *hdr, bool nopout_response)
3000 {
3001 	hdr->opcode		= ISCSI_OP_NOOP_IN;
3002 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3003         hton24(hdr->dlength, cmd->buf_ptr_size);
3004 	if (nopout_response)
3005 		put_unaligned_le64(0xFFFFFFFFFFFFFFFFULL, &hdr->lun);
3006 	hdr->itt		= cmd->init_task_tag;
3007 	hdr->ttt		= cpu_to_be32(cmd->targ_xfer_tag);
3008 	cmd->stat_sn		= (nopout_response) ? conn->stat_sn++ :
3009 				  conn->stat_sn;
3010 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3011 
3012 	if (nopout_response)
3013 		iscsit_increment_maxcmdsn(cmd, conn->sess);
3014 
3015 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3016 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3017 
3018 	pr_debug("Built NOPIN %s Response ITT: 0x%08x, TTT: 0x%08x,"
3019 		" StatSN: 0x%08x, Length %u\n", (nopout_response) ?
3020 		"Solicited" : "Unsolicited", cmd->init_task_tag,
3021 		cmd->targ_xfer_tag, cmd->stat_sn, cmd->buf_ptr_size);
3022 }
3023 EXPORT_SYMBOL(iscsit_build_nopin_rsp);
3024 
3025 /*
3026  *	Unsolicited NOPIN, either requesting a response or not.
3027  */
iscsit_send_unsolicited_nopin(struct iscsit_cmd * cmd,struct iscsit_conn * conn,int want_response)3028 static int iscsit_send_unsolicited_nopin(
3029 	struct iscsit_cmd *cmd,
3030 	struct iscsit_conn *conn,
3031 	int want_response)
3032 {
3033 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3034 	int ret;
3035 
3036 	iscsit_build_nopin_rsp(cmd, conn, hdr, false);
3037 
3038 	pr_debug("Sending Unsolicited NOPIN TTT: 0x%08x StatSN:"
3039 		" 0x%08x CID: %hu\n", hdr->ttt, cmd->stat_sn, conn->cid);
3040 
3041 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3042 	if (ret < 0)
3043 		return ret;
3044 
3045 	spin_lock_bh(&cmd->istate_lock);
3046 	cmd->i_state = want_response ?
3047 		ISTATE_SENT_NOPIN_WANT_RESPONSE : ISTATE_SENT_STATUS;
3048 	spin_unlock_bh(&cmd->istate_lock);
3049 
3050 	return 0;
3051 }
3052 
3053 static int
iscsit_send_nopin(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3054 iscsit_send_nopin(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3055 {
3056 	struct iscsi_nopin *hdr = (struct iscsi_nopin *)&cmd->pdu[0];
3057 
3058 	iscsit_build_nopin_rsp(cmd, conn, hdr, true);
3059 
3060 	/*
3061 	 * NOPOUT Ping Data is attached to struct iscsit_cmd->buf_ptr.
3062 	 * NOPOUT DataSegmentLength is at struct iscsit_cmd->buf_ptr_size.
3063 	 */
3064 	pr_debug("Echoing back %u bytes of ping data.\n", cmd->buf_ptr_size);
3065 
3066 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3067 						     cmd->buf_ptr,
3068 						     cmd->buf_ptr_size);
3069 }
3070 
iscsit_send_r2t(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3071 static int iscsit_send_r2t(
3072 	struct iscsit_cmd *cmd,
3073 	struct iscsit_conn *conn)
3074 {
3075 	struct iscsi_r2t *r2t;
3076 	struct iscsi_r2t_rsp *hdr;
3077 	int ret;
3078 
3079 	r2t = iscsit_get_r2t_from_list(cmd);
3080 	if (!r2t)
3081 		return -1;
3082 
3083 	hdr			= (struct iscsi_r2t_rsp *) cmd->pdu;
3084 	memset(hdr, 0, ISCSI_HDR_LEN);
3085 	hdr->opcode		= ISCSI_OP_R2T;
3086 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3087 	int_to_scsilun(cmd->se_cmd.orig_fe_lun,
3088 			(struct scsi_lun *)&hdr->lun);
3089 	hdr->itt		= cmd->init_task_tag;
3090 	if (conn->conn_transport->iscsit_get_r2t_ttt)
3091 		conn->conn_transport->iscsit_get_r2t_ttt(conn, cmd, r2t);
3092 	else
3093 		r2t->targ_xfer_tag = session_get_next_ttt(conn->sess);
3094 	hdr->ttt		= cpu_to_be32(r2t->targ_xfer_tag);
3095 	hdr->statsn		= cpu_to_be32(conn->stat_sn);
3096 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3097 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3098 	hdr->r2tsn		= cpu_to_be32(r2t->r2t_sn);
3099 	hdr->data_offset	= cpu_to_be32(r2t->offset);
3100 	hdr->data_length	= cpu_to_be32(r2t->xfer_len);
3101 
3102 	pr_debug("Built %sR2T, ITT: 0x%08x, TTT: 0x%08x, StatSN:"
3103 		" 0x%08x, R2TSN: 0x%08x, Offset: %u, DDTL: %u, CID: %hu\n",
3104 		(!r2t->recovery_r2t) ? "" : "Recovery ", cmd->init_task_tag,
3105 		r2t->targ_xfer_tag, ntohl(hdr->statsn), r2t->r2t_sn,
3106 			r2t->offset, r2t->xfer_len, conn->cid);
3107 
3108 	spin_lock_bh(&cmd->r2t_lock);
3109 	r2t->sent_r2t = 1;
3110 	spin_unlock_bh(&cmd->r2t_lock);
3111 
3112 	ret = conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3113 	if (ret < 0) {
3114 		return ret;
3115 	}
3116 
3117 	spin_lock_bh(&cmd->dataout_timeout_lock);
3118 	iscsit_start_dataout_timer(cmd, conn);
3119 	spin_unlock_bh(&cmd->dataout_timeout_lock);
3120 
3121 	return 0;
3122 }
3123 
3124 /*
3125  *	@recovery: If called from iscsi_task_reassign_complete_write() for
3126  *		connection recovery.
3127  */
iscsit_build_r2ts_for_cmd(struct iscsit_conn * conn,struct iscsit_cmd * cmd,bool recovery)3128 int iscsit_build_r2ts_for_cmd(
3129 	struct iscsit_conn *conn,
3130 	struct iscsit_cmd *cmd,
3131 	bool recovery)
3132 {
3133 	int first_r2t = 1;
3134 	u32 offset = 0, xfer_len = 0;
3135 
3136 	spin_lock_bh(&cmd->r2t_lock);
3137 	if (cmd->cmd_flags & ICF_SENT_LAST_R2T) {
3138 		spin_unlock_bh(&cmd->r2t_lock);
3139 		return 0;
3140 	}
3141 
3142 	if (conn->sess->sess_ops->DataSequenceInOrder &&
3143 	    !recovery)
3144 		cmd->r2t_offset = max(cmd->r2t_offset, cmd->write_data_done);
3145 
3146 	while (cmd->outstanding_r2ts < conn->sess->sess_ops->MaxOutstandingR2T) {
3147 		if (conn->sess->sess_ops->DataSequenceInOrder) {
3148 			offset = cmd->r2t_offset;
3149 
3150 			if (first_r2t && recovery) {
3151 				int new_data_end = offset +
3152 					conn->sess->sess_ops->MaxBurstLength -
3153 					cmd->next_burst_len;
3154 
3155 				if (new_data_end > cmd->se_cmd.data_length)
3156 					xfer_len = cmd->se_cmd.data_length - offset;
3157 				else
3158 					xfer_len =
3159 						conn->sess->sess_ops->MaxBurstLength -
3160 						cmd->next_burst_len;
3161 			} else {
3162 				int new_data_end = offset +
3163 					conn->sess->sess_ops->MaxBurstLength;
3164 
3165 				if (new_data_end > cmd->se_cmd.data_length)
3166 					xfer_len = cmd->se_cmd.data_length - offset;
3167 				else
3168 					xfer_len = conn->sess->sess_ops->MaxBurstLength;
3169 			}
3170 
3171 			if ((s32)xfer_len < 0) {
3172 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3173 				break;
3174 			}
3175 
3176 			cmd->r2t_offset += xfer_len;
3177 
3178 			if (cmd->r2t_offset == cmd->se_cmd.data_length)
3179 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3180 		} else {
3181 			struct iscsi_seq *seq;
3182 
3183 			seq = iscsit_get_seq_holder_for_r2t(cmd);
3184 			if (!seq) {
3185 				spin_unlock_bh(&cmd->r2t_lock);
3186 				return -1;
3187 			}
3188 
3189 			offset = seq->offset;
3190 			xfer_len = seq->xfer_len;
3191 
3192 			if (cmd->seq_send_order == cmd->seq_count)
3193 				cmd->cmd_flags |= ICF_SENT_LAST_R2T;
3194 		}
3195 		cmd->outstanding_r2ts++;
3196 		first_r2t = 0;
3197 
3198 		if (iscsit_add_r2t_to_list(cmd, offset, xfer_len, 0, 0) < 0) {
3199 			spin_unlock_bh(&cmd->r2t_lock);
3200 			return -1;
3201 		}
3202 
3203 		if (cmd->cmd_flags & ICF_SENT_LAST_R2T)
3204 			break;
3205 	}
3206 	spin_unlock_bh(&cmd->r2t_lock);
3207 
3208 	return 0;
3209 }
3210 EXPORT_SYMBOL(iscsit_build_r2ts_for_cmd);
3211 
iscsit_build_rsp_pdu(struct iscsit_cmd * cmd,struct iscsit_conn * conn,bool inc_stat_sn,struct iscsi_scsi_rsp * hdr)3212 void iscsit_build_rsp_pdu(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3213 			bool inc_stat_sn, struct iscsi_scsi_rsp *hdr)
3214 {
3215 	if (inc_stat_sn)
3216 		cmd->stat_sn = conn->stat_sn++;
3217 
3218 	atomic_long_inc(&conn->sess->rsp_pdus);
3219 
3220 	memset(hdr, 0, ISCSI_HDR_LEN);
3221 	hdr->opcode		= ISCSI_OP_SCSI_CMD_RSP;
3222 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3223 	if (cmd->se_cmd.se_cmd_flags & SCF_OVERFLOW_BIT) {
3224 		hdr->flags |= ISCSI_FLAG_CMD_OVERFLOW;
3225 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3226 	} else if (cmd->se_cmd.se_cmd_flags & SCF_UNDERFLOW_BIT) {
3227 		hdr->flags |= ISCSI_FLAG_CMD_UNDERFLOW;
3228 		hdr->residual_count = cpu_to_be32(cmd->se_cmd.residual_count);
3229 	}
3230 	hdr->response		= cmd->iscsi_response;
3231 	hdr->cmd_status		= cmd->se_cmd.scsi_status;
3232 	hdr->itt		= cmd->init_task_tag;
3233 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3234 
3235 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3236 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3237 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3238 
3239 	pr_debug("Built SCSI Response, ITT: 0x%08x, StatSN: 0x%08x,"
3240 		" Response: 0x%02x, SAM Status: 0x%02x, CID: %hu\n",
3241 		cmd->init_task_tag, cmd->stat_sn, cmd->se_cmd.scsi_status,
3242 		cmd->se_cmd.scsi_status, conn->cid);
3243 }
3244 EXPORT_SYMBOL(iscsit_build_rsp_pdu);
3245 
iscsit_send_response(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3246 static int iscsit_send_response(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3247 {
3248 	struct iscsi_scsi_rsp *hdr = (struct iscsi_scsi_rsp *)&cmd->pdu[0];
3249 	bool inc_stat_sn = (cmd->i_state == ISTATE_SEND_STATUS);
3250 	void *data_buf = NULL;
3251 	u32 padding = 0, data_buf_len = 0;
3252 
3253 	iscsit_build_rsp_pdu(cmd, conn, inc_stat_sn, hdr);
3254 
3255 	/*
3256 	 * Attach SENSE DATA payload to iSCSI Response PDU
3257 	 */
3258 	if (cmd->se_cmd.sense_buffer &&
3259 	   ((cmd->se_cmd.se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) ||
3260 	    (cmd->se_cmd.se_cmd_flags & SCF_EMULATED_TASK_SENSE))) {
3261 		put_unaligned_be16(cmd->se_cmd.scsi_sense_length, cmd->sense_buffer);
3262 		cmd->se_cmd.scsi_sense_length += sizeof (__be16);
3263 
3264 		padding		= -(cmd->se_cmd.scsi_sense_length) & 3;
3265 		hton24(hdr->dlength, (u32)cmd->se_cmd.scsi_sense_length);
3266 		data_buf = cmd->sense_buffer;
3267 		data_buf_len = cmd->se_cmd.scsi_sense_length + padding;
3268 
3269 		if (padding) {
3270 			memset(cmd->sense_buffer +
3271 				cmd->se_cmd.scsi_sense_length, 0, padding);
3272 			pr_debug("Adding %u bytes of padding to"
3273 				" SENSE.\n", padding);
3274 		}
3275 
3276 		pr_debug("Attaching SENSE DATA: %u bytes to iSCSI"
3277 				" Response PDU\n",
3278 				cmd->se_cmd.scsi_sense_length);
3279 	}
3280 
3281 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, data_buf,
3282 						     data_buf_len);
3283 }
3284 
iscsit_convert_tcm_tmr_rsp(struct se_tmr_req * se_tmr)3285 static u8 iscsit_convert_tcm_tmr_rsp(struct se_tmr_req *se_tmr)
3286 {
3287 	switch (se_tmr->response) {
3288 	case TMR_FUNCTION_COMPLETE:
3289 		return ISCSI_TMF_RSP_COMPLETE;
3290 	case TMR_TASK_DOES_NOT_EXIST:
3291 		return ISCSI_TMF_RSP_NO_TASK;
3292 	case TMR_LUN_DOES_NOT_EXIST:
3293 		return ISCSI_TMF_RSP_NO_LUN;
3294 	case TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED:
3295 		return ISCSI_TMF_RSP_NOT_SUPPORTED;
3296 	case TMR_FUNCTION_REJECTED:
3297 	default:
3298 		return ISCSI_TMF_RSP_REJECTED;
3299 	}
3300 }
3301 
3302 void
iscsit_build_task_mgt_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_tm_rsp * hdr)3303 iscsit_build_task_mgt_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3304 			  struct iscsi_tm_rsp *hdr)
3305 {
3306 	struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req;
3307 
3308 	hdr->opcode		= ISCSI_OP_SCSI_TMFUNC_RSP;
3309 	hdr->flags		= ISCSI_FLAG_CMD_FINAL;
3310 	hdr->response		= iscsit_convert_tcm_tmr_rsp(se_tmr);
3311 	hdr->itt		= cmd->init_task_tag;
3312 	cmd->stat_sn		= conn->stat_sn++;
3313 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3314 
3315 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3316 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3317 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3318 
3319 	pr_debug("Built Task Management Response ITT: 0x%08x,"
3320 		" StatSN: 0x%08x, Response: 0x%02x, CID: %hu\n",
3321 		cmd->init_task_tag, cmd->stat_sn, hdr->response, conn->cid);
3322 }
3323 EXPORT_SYMBOL(iscsit_build_task_mgt_rsp);
3324 
3325 static int
iscsit_send_task_mgt_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3326 iscsit_send_task_mgt_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn)
3327 {
3328 	struct iscsi_tm_rsp *hdr = (struct iscsi_tm_rsp *)&cmd->pdu[0];
3329 
3330 	iscsit_build_task_mgt_rsp(cmd, conn, hdr);
3331 
3332 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL, NULL, 0);
3333 }
3334 
3335 #define SENDTARGETS_BUF_LIMIT 32768U
3336 
3337 static int
iscsit_build_sendtargets_response(struct iscsit_cmd * cmd,enum iscsit_transport_type network_transport,int skip_bytes,bool * completed)3338 iscsit_build_sendtargets_response(struct iscsit_cmd *cmd,
3339 				  enum iscsit_transport_type network_transport,
3340 				  int skip_bytes, bool *completed)
3341 {
3342 	char *payload = NULL;
3343 	struct iscsit_conn *conn = cmd->conn;
3344 	struct iscsi_portal_group *tpg;
3345 	struct iscsi_tiqn *tiqn;
3346 	struct iscsi_tpg_np *tpg_np;
3347 	int buffer_len, end_of_buf = 0, len = 0, payload_len = 0;
3348 	int target_name_printed;
3349 	unsigned char buf[ISCSI_IQN_LEN+12]; /* iqn + "TargetName=" + \0 */
3350 	unsigned char *text_in = cmd->text_in_ptr, *text_ptr = NULL;
3351 	bool active;
3352 
3353 	buffer_len = min(conn->conn_ops->MaxRecvDataSegmentLength,
3354 			 SENDTARGETS_BUF_LIMIT);
3355 
3356 	payload = kzalloc(buffer_len, GFP_KERNEL);
3357 	if (!payload)
3358 		return -ENOMEM;
3359 
3360 	/*
3361 	 * Locate pointer to iqn./eui. string for ICF_SENDTARGETS_SINGLE
3362 	 * explicit case..
3363 	 */
3364 	if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) {
3365 		text_ptr = strchr(text_in, '=');
3366 		if (!text_ptr) {
3367 			pr_err("Unable to locate '=' string in text_in:"
3368 			       " %s\n", text_in);
3369 			kfree(payload);
3370 			return -EINVAL;
3371 		}
3372 		/*
3373 		 * Skip over '=' character..
3374 		 */
3375 		text_ptr += 1;
3376 	}
3377 
3378 	spin_lock(&tiqn_lock);
3379 	list_for_each_entry(tiqn, &g_tiqn_list, tiqn_list) {
3380 		if ((cmd->cmd_flags & ICF_SENDTARGETS_SINGLE) &&
3381 		     strcmp(tiqn->tiqn, text_ptr)) {
3382 			continue;
3383 		}
3384 
3385 		target_name_printed = 0;
3386 
3387 		spin_lock(&tiqn->tiqn_tpg_lock);
3388 		list_for_each_entry(tpg, &tiqn->tiqn_tpg_list, tpg_list) {
3389 
3390 			/* If demo_mode_discovery=0 and generate_node_acls=0
3391 			 * (demo mode dislabed) do not return
3392 			 * TargetName+TargetAddress unless a NodeACL exists.
3393 			 */
3394 
3395 			if ((tpg->tpg_attrib.generate_node_acls == 0) &&
3396 			    (tpg->tpg_attrib.demo_mode_discovery == 0) &&
3397 			    (!target_tpg_has_node_acl(&tpg->tpg_se_tpg,
3398 				cmd->conn->sess->sess_ops->InitiatorName))) {
3399 				continue;
3400 			}
3401 
3402 			spin_lock(&tpg->tpg_state_lock);
3403 			active = (tpg->tpg_state == TPG_STATE_ACTIVE);
3404 			spin_unlock(&tpg->tpg_state_lock);
3405 
3406 			if (!active && tpg->tpg_attrib.tpg_enabled_sendtargets)
3407 				continue;
3408 
3409 			spin_lock(&tpg->tpg_np_lock);
3410 			list_for_each_entry(tpg_np, &tpg->tpg_gnp_list,
3411 						tpg_np_list) {
3412 				struct iscsi_np *np = tpg_np->tpg_np;
3413 				struct sockaddr_storage *sockaddr;
3414 
3415 				if (np->np_network_transport != network_transport)
3416 					continue;
3417 
3418 				if (!target_name_printed) {
3419 					len = sprintf(buf, "TargetName=%s",
3420 						      tiqn->tiqn);
3421 					len += 1;
3422 
3423 					if ((len + payload_len) > buffer_len) {
3424 						spin_unlock(&tpg->tpg_np_lock);
3425 						spin_unlock(&tiqn->tiqn_tpg_lock);
3426 						end_of_buf = 1;
3427 						goto eob;
3428 					}
3429 
3430 					if (skip_bytes && len <= skip_bytes) {
3431 						skip_bytes -= len;
3432 					} else {
3433 						memcpy(payload + payload_len, buf, len);
3434 						payload_len += len;
3435 						target_name_printed = 1;
3436 						if (len > skip_bytes)
3437 							skip_bytes = 0;
3438 					}
3439 				}
3440 
3441 				if (inet_addr_is_any(&np->np_sockaddr))
3442 					sockaddr = &conn->local_sockaddr;
3443 				else
3444 					sockaddr = &np->np_sockaddr;
3445 
3446 				len = sprintf(buf, "TargetAddress="
3447 					      "%pISpc,%hu",
3448 					      sockaddr,
3449 					      tpg->tpgt);
3450 				len += 1;
3451 
3452 				if ((len + payload_len) > buffer_len) {
3453 					spin_unlock(&tpg->tpg_np_lock);
3454 					spin_unlock(&tiqn->tiqn_tpg_lock);
3455 					end_of_buf = 1;
3456 					goto eob;
3457 				}
3458 
3459 				if (skip_bytes && len <= skip_bytes) {
3460 					skip_bytes -= len;
3461 				} else {
3462 					memcpy(payload + payload_len, buf, len);
3463 					payload_len += len;
3464 					if (len > skip_bytes)
3465 						skip_bytes = 0;
3466 				}
3467 			}
3468 			spin_unlock(&tpg->tpg_np_lock);
3469 		}
3470 		spin_unlock(&tiqn->tiqn_tpg_lock);
3471 eob:
3472 		if (end_of_buf) {
3473 			*completed = false;
3474 			break;
3475 		}
3476 
3477 		if (cmd->cmd_flags & ICF_SENDTARGETS_SINGLE)
3478 			break;
3479 	}
3480 	spin_unlock(&tiqn_lock);
3481 
3482 	cmd->buf_ptr = payload;
3483 
3484 	return payload_len;
3485 }
3486 
3487 int
iscsit_build_text_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_text_rsp * hdr,enum iscsit_transport_type network_transport)3488 iscsit_build_text_rsp(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3489 		      struct iscsi_text_rsp *hdr,
3490 		      enum iscsit_transport_type network_transport)
3491 {
3492 	int text_length, padding;
3493 	bool completed = true;
3494 
3495 	text_length = iscsit_build_sendtargets_response(cmd, network_transport,
3496 							cmd->read_data_done,
3497 							&completed);
3498 	if (text_length < 0)
3499 		return text_length;
3500 
3501 	if (completed) {
3502 		hdr->flags = ISCSI_FLAG_CMD_FINAL;
3503 	} else {
3504 		hdr->flags = ISCSI_FLAG_TEXT_CONTINUE;
3505 		cmd->read_data_done += text_length;
3506 		if (cmd->targ_xfer_tag == 0xFFFFFFFF)
3507 			cmd->targ_xfer_tag = session_get_next_ttt(conn->sess);
3508 	}
3509 	hdr->opcode = ISCSI_OP_TEXT_RSP;
3510 	padding = ((-text_length) & 3);
3511 	hton24(hdr->dlength, text_length);
3512 	hdr->itt = cmd->init_task_tag;
3513 	hdr->ttt = cpu_to_be32(cmd->targ_xfer_tag);
3514 	cmd->stat_sn = conn->stat_sn++;
3515 	hdr->statsn = cpu_to_be32(cmd->stat_sn);
3516 
3517 	iscsit_increment_maxcmdsn(cmd, conn->sess);
3518 	/*
3519 	 * Reset maxcmdsn_inc in multi-part text payload exchanges to
3520 	 * correctly increment MaxCmdSN for each response answering a
3521 	 * non immediate text request with a valid CmdSN.
3522 	 */
3523 	cmd->maxcmdsn_inc = 0;
3524 	hdr->exp_cmdsn = cpu_to_be32(conn->sess->exp_cmd_sn);
3525 	hdr->max_cmdsn = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3526 
3527 	pr_debug("Built Text Response: ITT: 0x%08x, TTT: 0x%08x, StatSN: 0x%08x,"
3528 		" Length: %u, CID: %hu F: %d C: %d\n", cmd->init_task_tag,
3529 		cmd->targ_xfer_tag, cmd->stat_sn, text_length, conn->cid,
3530 		!!(hdr->flags & ISCSI_FLAG_CMD_FINAL),
3531 		!!(hdr->flags & ISCSI_FLAG_TEXT_CONTINUE));
3532 
3533 	return text_length + padding;
3534 }
3535 EXPORT_SYMBOL(iscsit_build_text_rsp);
3536 
iscsit_send_text_rsp(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3537 static int iscsit_send_text_rsp(
3538 	struct iscsit_cmd *cmd,
3539 	struct iscsit_conn *conn)
3540 {
3541 	struct iscsi_text_rsp *hdr = (struct iscsi_text_rsp *)cmd->pdu;
3542 	int text_length;
3543 
3544 	text_length = iscsit_build_text_rsp(cmd, conn, hdr,
3545 				conn->conn_transport->transport_type);
3546 	if (text_length < 0)
3547 		return text_length;
3548 
3549 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3550 						     cmd->buf_ptr,
3551 						     text_length);
3552 }
3553 
3554 void
iscsit_build_reject(struct iscsit_cmd * cmd,struct iscsit_conn * conn,struct iscsi_reject * hdr)3555 iscsit_build_reject(struct iscsit_cmd *cmd, struct iscsit_conn *conn,
3556 		    struct iscsi_reject *hdr)
3557 {
3558 	hdr->opcode		= ISCSI_OP_REJECT;
3559 	hdr->reason		= cmd->reject_reason;
3560 	hdr->flags		|= ISCSI_FLAG_CMD_FINAL;
3561 	hton24(hdr->dlength, ISCSI_HDR_LEN);
3562 	hdr->ffffffff		= cpu_to_be32(0xffffffff);
3563 	cmd->stat_sn		= conn->stat_sn++;
3564 	hdr->statsn		= cpu_to_be32(cmd->stat_sn);
3565 	hdr->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
3566 	hdr->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
3567 
3568 }
3569 EXPORT_SYMBOL(iscsit_build_reject);
3570 
iscsit_send_reject(struct iscsit_cmd * cmd,struct iscsit_conn * conn)3571 static int iscsit_send_reject(
3572 	struct iscsit_cmd *cmd,
3573 	struct iscsit_conn *conn)
3574 {
3575 	struct iscsi_reject *hdr = (struct iscsi_reject *)&cmd->pdu[0];
3576 
3577 	iscsit_build_reject(cmd, conn, hdr);
3578 
3579 	pr_debug("Built Reject PDU StatSN: 0x%08x, Reason: 0x%02x,"
3580 		" CID: %hu\n", ntohl(hdr->statsn), hdr->reason, conn->cid);
3581 
3582 	return conn->conn_transport->iscsit_xmit_pdu(conn, cmd, NULL,
3583 						     cmd->buf_ptr,
3584 						     ISCSI_HDR_LEN);
3585 }
3586 
iscsit_thread_get_cpumask(struct iscsit_conn * conn)3587 void iscsit_thread_get_cpumask(struct iscsit_conn *conn)
3588 {
3589 	int ord, cpu;
3590 	cpumask_var_t conn_allowed_cpumask;
3591 
3592 	/*
3593 	 * bitmap_id is assigned from iscsit_global->ts_bitmap from
3594 	 * within iscsit_start_kthreads()
3595 	 *
3596 	 * Here we use bitmap_id to determine which CPU that this
3597 	 * iSCSI connection's RX/TX threads will be scheduled to
3598 	 * execute upon.
3599 	 */
3600 	if (!zalloc_cpumask_var(&conn_allowed_cpumask, GFP_KERNEL)) {
3601 		ord = conn->bitmap_id % cpumask_weight(cpu_online_mask);
3602 		for_each_online_cpu(cpu) {
3603 			if (ord-- == 0) {
3604 				cpumask_set_cpu(cpu, conn->conn_cpumask);
3605 				return;
3606 			}
3607 		}
3608 	} else {
3609 		cpumask_and(conn_allowed_cpumask, iscsit_global->allowed_cpumask,
3610 			cpu_online_mask);
3611 
3612 		cpumask_clear(conn->conn_cpumask);
3613 		ord = conn->bitmap_id % cpumask_weight(conn_allowed_cpumask);
3614 		for_each_cpu(cpu, conn_allowed_cpumask) {
3615 			if (ord-- == 0) {
3616 				cpumask_set_cpu(cpu, conn->conn_cpumask);
3617 				free_cpumask_var(conn_allowed_cpumask);
3618 				return;
3619 			}
3620 		}
3621 		free_cpumask_var(conn_allowed_cpumask);
3622 	}
3623 	/*
3624 	 * This should never be reached..
3625 	 */
3626 	dump_stack();
3627 	cpumask_setall(conn->conn_cpumask);
3628 }
3629 
iscsit_thread_reschedule(struct iscsit_conn * conn)3630 static void iscsit_thread_reschedule(struct iscsit_conn *conn)
3631 {
3632 	/*
3633 	 * If iscsit_global->allowed_cpumask modified, reschedule iSCSI
3634 	 * connection's RX/TX threads update conn->allowed_cpumask.
3635 	 */
3636 	if (!cpumask_equal(iscsit_global->allowed_cpumask,
3637 			   conn->allowed_cpumask)) {
3638 		iscsit_thread_get_cpumask(conn);
3639 		conn->conn_tx_reset_cpumask = 1;
3640 		conn->conn_rx_reset_cpumask = 1;
3641 		cpumask_copy(conn->allowed_cpumask,
3642 			     iscsit_global->allowed_cpumask);
3643 	}
3644 }
3645 
iscsit_thread_check_cpumask(struct iscsit_conn * conn,struct task_struct * p,int mode)3646 void iscsit_thread_check_cpumask(
3647 	struct iscsit_conn *conn,
3648 	struct task_struct *p,
3649 	int mode)
3650 {
3651 	/*
3652 	 * The TX and RX threads maybe call iscsit_thread_check_cpumask()
3653 	 * at the same time. The RX thread might be faster and return from
3654 	 * iscsit_thread_reschedule() with conn_rx_reset_cpumask set to 0.
3655 	 * Then the TX thread sets it back to 1.
3656 	 * The next time the RX thread loops, it sees conn_rx_reset_cpumask
3657 	 * set to 1 and calls set_cpus_allowed_ptr() again and set it to 0.
3658 	 */
3659 	iscsit_thread_reschedule(conn);
3660 
3661 	/*
3662 	 * mode == 1 signals iscsi_target_tx_thread() usage.
3663 	 * mode == 0 signals iscsi_target_rx_thread() usage.
3664 	 */
3665 	if (mode == 1) {
3666 		if (!conn->conn_tx_reset_cpumask)
3667 			return;
3668 	} else {
3669 		if (!conn->conn_rx_reset_cpumask)
3670 			return;
3671 	}
3672 
3673 	/*
3674 	 * Update the CPU mask for this single kthread so that
3675 	 * both TX and RX kthreads are scheduled to run on the
3676 	 * same CPU.
3677 	 */
3678 	set_cpus_allowed_ptr(p, conn->conn_cpumask);
3679 	if (mode == 1)
3680 		conn->conn_tx_reset_cpumask = 0;
3681 	else
3682 		conn->conn_rx_reset_cpumask = 0;
3683 }
3684 EXPORT_SYMBOL(iscsit_thread_check_cpumask);
3685 
3686 int
iscsit_immediate_queue(struct iscsit_conn * conn,struct iscsit_cmd * cmd,int state)3687 iscsit_immediate_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
3688 {
3689 	int ret;
3690 
3691 	switch (state) {
3692 	case ISTATE_SEND_R2T:
3693 		ret = iscsit_send_r2t(cmd, conn);
3694 		if (ret < 0)
3695 			goto err;
3696 		break;
3697 	case ISTATE_REMOVE:
3698 		spin_lock_bh(&conn->cmd_lock);
3699 		list_del_init(&cmd->i_conn_node);
3700 		spin_unlock_bh(&conn->cmd_lock);
3701 
3702 		iscsit_free_cmd(cmd, false);
3703 		break;
3704 	case ISTATE_SEND_NOPIN_WANT_RESPONSE:
3705 		iscsit_mod_nopin_response_timer(conn);
3706 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 1);
3707 		if (ret < 0)
3708 			goto err;
3709 		break;
3710 	case ISTATE_SEND_NOPIN_NO_RESPONSE:
3711 		ret = iscsit_send_unsolicited_nopin(cmd, conn, 0);
3712 		if (ret < 0)
3713 			goto err;
3714 		break;
3715 	default:
3716 		pr_err("Unknown Opcode: 0x%02x ITT:"
3717 		       " 0x%08x, i_state: %d on CID: %hu\n",
3718 		       cmd->iscsi_opcode, cmd->init_task_tag, state,
3719 		       conn->cid);
3720 		goto err;
3721 	}
3722 
3723 	return 0;
3724 
3725 err:
3726 	return -1;
3727 }
3728 EXPORT_SYMBOL(iscsit_immediate_queue);
3729 
3730 static int
iscsit_handle_immediate_queue(struct iscsit_conn * conn)3731 iscsit_handle_immediate_queue(struct iscsit_conn *conn)
3732 {
3733 	struct iscsit_transport *t = conn->conn_transport;
3734 	struct iscsi_queue_req *qr;
3735 	struct iscsit_cmd *cmd;
3736 	u8 state;
3737 	int ret;
3738 
3739 	while ((qr = iscsit_get_cmd_from_immediate_queue(conn))) {
3740 		atomic_set(&conn->check_immediate_queue, 0);
3741 		cmd = qr->cmd;
3742 		state = qr->state;
3743 		kmem_cache_free(lio_qr_cache, qr);
3744 
3745 		ret = t->iscsit_immediate_queue(conn, cmd, state);
3746 		if (ret < 0)
3747 			return ret;
3748 	}
3749 
3750 	return 0;
3751 }
3752 
3753 int
iscsit_response_queue(struct iscsit_conn * conn,struct iscsit_cmd * cmd,int state)3754 iscsit_response_queue(struct iscsit_conn *conn, struct iscsit_cmd *cmd, int state)
3755 {
3756 	int ret;
3757 
3758 check_rsp_state:
3759 	switch (state) {
3760 	case ISTATE_SEND_DATAIN:
3761 		ret = iscsit_send_datain(cmd, conn);
3762 		if (ret < 0)
3763 			goto err;
3764 		else if (!ret)
3765 			/* more drs */
3766 			goto check_rsp_state;
3767 		else if (ret == 1) {
3768 			/* all done */
3769 			spin_lock_bh(&cmd->istate_lock);
3770 			cmd->i_state = ISTATE_SENT_STATUS;
3771 			spin_unlock_bh(&cmd->istate_lock);
3772 
3773 			if (atomic_read(&conn->check_immediate_queue))
3774 				return 1;
3775 
3776 			return 0;
3777 		} else if (ret == 2) {
3778 			/* Still must send status,
3779 			   SCF_TRANSPORT_TASK_SENSE was set */
3780 			spin_lock_bh(&cmd->istate_lock);
3781 			cmd->i_state = ISTATE_SEND_STATUS;
3782 			spin_unlock_bh(&cmd->istate_lock);
3783 			state = ISTATE_SEND_STATUS;
3784 			goto check_rsp_state;
3785 		}
3786 
3787 		break;
3788 	case ISTATE_SEND_STATUS:
3789 	case ISTATE_SEND_STATUS_RECOVERY:
3790 		ret = iscsit_send_response(cmd, conn);
3791 		break;
3792 	case ISTATE_SEND_LOGOUTRSP:
3793 		ret = iscsit_send_logout(cmd, conn);
3794 		break;
3795 	case ISTATE_SEND_ASYNCMSG:
3796 		ret = iscsit_send_conn_drop_async_message(
3797 			cmd, conn);
3798 		break;
3799 	case ISTATE_SEND_NOPIN:
3800 		ret = iscsit_send_nopin(cmd, conn);
3801 		break;
3802 	case ISTATE_SEND_REJECT:
3803 		ret = iscsit_send_reject(cmd, conn);
3804 		break;
3805 	case ISTATE_SEND_TASKMGTRSP:
3806 		ret = iscsit_send_task_mgt_rsp(cmd, conn);
3807 		if (ret != 0)
3808 			break;
3809 		ret = iscsit_tmr_post_handler(cmd, conn);
3810 		if (ret != 0)
3811 			iscsit_fall_back_to_erl0(conn->sess);
3812 		break;
3813 	case ISTATE_SEND_TEXTRSP:
3814 		ret = iscsit_send_text_rsp(cmd, conn);
3815 		break;
3816 	default:
3817 		pr_err("Unknown Opcode: 0x%02x ITT:"
3818 		       " 0x%08x, i_state: %d on CID: %hu\n",
3819 		       cmd->iscsi_opcode, cmd->init_task_tag,
3820 		       state, conn->cid);
3821 		goto err;
3822 	}
3823 	if (ret < 0)
3824 		goto err;
3825 
3826 	switch (state) {
3827 	case ISTATE_SEND_LOGOUTRSP:
3828 		if (!iscsit_logout_post_handler(cmd, conn))
3829 			return -ECONNRESET;
3830 		fallthrough;
3831 	case ISTATE_SEND_STATUS:
3832 	case ISTATE_SEND_ASYNCMSG:
3833 	case ISTATE_SEND_NOPIN:
3834 	case ISTATE_SEND_STATUS_RECOVERY:
3835 	case ISTATE_SEND_TEXTRSP:
3836 	case ISTATE_SEND_TASKMGTRSP:
3837 	case ISTATE_SEND_REJECT:
3838 		spin_lock_bh(&cmd->istate_lock);
3839 		cmd->i_state = ISTATE_SENT_STATUS;
3840 		spin_unlock_bh(&cmd->istate_lock);
3841 		break;
3842 	default:
3843 		pr_err("Unknown Opcode: 0x%02x ITT:"
3844 		       " 0x%08x, i_state: %d on CID: %hu\n",
3845 		       cmd->iscsi_opcode, cmd->init_task_tag,
3846 		       cmd->i_state, conn->cid);
3847 		goto err;
3848 	}
3849 
3850 	if (atomic_read(&conn->check_immediate_queue))
3851 		return 1;
3852 
3853 	return 0;
3854 
3855 err:
3856 	return -1;
3857 }
3858 EXPORT_SYMBOL(iscsit_response_queue);
3859 
iscsit_handle_response_queue(struct iscsit_conn * conn)3860 static int iscsit_handle_response_queue(struct iscsit_conn *conn)
3861 {
3862 	struct iscsit_transport *t = conn->conn_transport;
3863 	struct iscsi_queue_req *qr;
3864 	struct iscsit_cmd *cmd;
3865 	u8 state;
3866 	int ret;
3867 
3868 	while ((qr = iscsit_get_cmd_from_response_queue(conn))) {
3869 		cmd = qr->cmd;
3870 		state = qr->state;
3871 		kmem_cache_free(lio_qr_cache, qr);
3872 
3873 		ret = t->iscsit_response_queue(conn, cmd, state);
3874 		if (ret == 1 || ret < 0)
3875 			return ret;
3876 	}
3877 
3878 	return 0;
3879 }
3880 
iscsi_target_tx_thread(void * arg)3881 int iscsi_target_tx_thread(void *arg)
3882 {
3883 	int ret = 0;
3884 	struct iscsit_conn *conn = arg;
3885 	bool conn_freed = false;
3886 
3887 	/*
3888 	 * Allow ourselves to be interrupted by SIGINT so that a
3889 	 * connection recovery / failure event can be triggered externally.
3890 	 */
3891 	allow_signal(SIGINT);
3892 
3893 	while (!kthread_should_stop()) {
3894 		/*
3895 		 * Ensure that both TX and RX per connection kthreads
3896 		 * are scheduled to run on the same CPU.
3897 		 */
3898 		iscsit_thread_check_cpumask(conn, current, 1);
3899 
3900 		wait_event_interruptible(conn->queues_wq,
3901 					 !iscsit_conn_all_queues_empty(conn));
3902 
3903 		if (signal_pending(current))
3904 			goto transport_err;
3905 
3906 get_immediate:
3907 		ret = iscsit_handle_immediate_queue(conn);
3908 		if (ret < 0)
3909 			goto transport_err;
3910 
3911 		ret = iscsit_handle_response_queue(conn);
3912 		if (ret == 1) {
3913 			goto get_immediate;
3914 		} else if (ret == -ECONNRESET) {
3915 			conn_freed = true;
3916 			goto out;
3917 		} else if (ret < 0) {
3918 			goto transport_err;
3919 		}
3920 	}
3921 
3922 transport_err:
3923 	/*
3924 	 * Avoid the normal connection failure code-path if this connection
3925 	 * is still within LOGIN mode, and iscsi_np process context is
3926 	 * responsible for cleaning up the early connection failure.
3927 	 */
3928 	if (conn->conn_state != TARG_CONN_STATE_IN_LOGIN)
3929 		iscsit_take_action_for_connection_exit(conn, &conn_freed);
3930 out:
3931 	if (!conn_freed) {
3932 		while (!kthread_should_stop()) {
3933 			msleep(100);
3934 		}
3935 	}
3936 	return 0;
3937 }
3938 
iscsi_target_rx_opcode(struct iscsit_conn * conn,unsigned char * buf)3939 static int iscsi_target_rx_opcode(struct iscsit_conn *conn, unsigned char *buf)
3940 {
3941 	struct iscsi_hdr *hdr = (struct iscsi_hdr *)buf;
3942 	struct iscsit_cmd *cmd;
3943 	int ret = 0;
3944 
3945 	switch (hdr->opcode & ISCSI_OPCODE_MASK) {
3946 	case ISCSI_OP_SCSI_CMD:
3947 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3948 		if (!cmd)
3949 			goto reject;
3950 
3951 		ret = iscsit_handle_scsi_cmd(conn, cmd, buf);
3952 		break;
3953 	case ISCSI_OP_SCSI_DATA_OUT:
3954 		ret = iscsit_handle_data_out(conn, buf);
3955 		break;
3956 	case ISCSI_OP_NOOP_OUT:
3957 		cmd = NULL;
3958 		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
3959 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3960 			if (!cmd)
3961 				goto reject;
3962 		}
3963 		ret = iscsit_handle_nop_out(conn, cmd, buf);
3964 		break;
3965 	case ISCSI_OP_SCSI_TMFUNC:
3966 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3967 		if (!cmd)
3968 			goto reject;
3969 
3970 		ret = iscsit_handle_task_mgt_cmd(conn, cmd, buf);
3971 		break;
3972 	case ISCSI_OP_TEXT:
3973 		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
3974 			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
3975 			if (!cmd)
3976 				goto reject;
3977 		} else {
3978 			cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3979 			if (!cmd)
3980 				goto reject;
3981 		}
3982 
3983 		ret = iscsit_handle_text_cmd(conn, cmd, buf);
3984 		break;
3985 	case ISCSI_OP_LOGOUT:
3986 		cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
3987 		if (!cmd)
3988 			goto reject;
3989 
3990 		ret = iscsit_handle_logout_cmd(conn, cmd, buf);
3991 		if (ret > 0)
3992 			wait_for_completion_timeout(&conn->conn_logout_comp,
3993 					SECONDS_FOR_LOGOUT_COMP * HZ);
3994 		break;
3995 	case ISCSI_OP_SNACK:
3996 		ret = iscsit_handle_snack(conn, buf);
3997 		break;
3998 	default:
3999 		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", hdr->opcode);
4000 		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
4001 			pr_err("Cannot recover from unknown"
4002 			" opcode while ERL=0, closing iSCSI connection.\n");
4003 			return -1;
4004 		}
4005 		pr_err("Unable to recover from unknown opcode while OFMarker=No,"
4006 		       " closing iSCSI connection.\n");
4007 		ret = -1;
4008 		break;
4009 	}
4010 
4011 	return ret;
4012 reject:
4013 	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf);
4014 }
4015 
iscsi_target_check_conn_state(struct iscsit_conn * conn)4016 static bool iscsi_target_check_conn_state(struct iscsit_conn *conn)
4017 {
4018 	bool ret;
4019 
4020 	spin_lock_bh(&conn->state_lock);
4021 	ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN);
4022 	spin_unlock_bh(&conn->state_lock);
4023 
4024 	return ret;
4025 }
4026 
iscsit_get_rx_pdu(struct iscsit_conn * conn)4027 static void iscsit_get_rx_pdu(struct iscsit_conn *conn)
4028 {
4029 	int ret;
4030 	u8 *buffer, *tmp_buf, opcode;
4031 	u32 checksum = 0, digest = 0;
4032 	struct iscsi_hdr *hdr;
4033 	struct kvec iov;
4034 
4035 	buffer = kcalloc(ISCSI_HDR_LEN, sizeof(*buffer), GFP_KERNEL);
4036 	if (!buffer)
4037 		return;
4038 
4039 	while (!kthread_should_stop()) {
4040 		/*
4041 		 * Ensure that both TX and RX per connection kthreads
4042 		 * are scheduled to run on the same CPU.
4043 		 */
4044 		iscsit_thread_check_cpumask(conn, current, 0);
4045 
4046 		memset(&iov, 0, sizeof(struct kvec));
4047 
4048 		iov.iov_base	= buffer;
4049 		iov.iov_len	= ISCSI_HDR_LEN;
4050 
4051 		ret = rx_data(conn, &iov, 1, ISCSI_HDR_LEN);
4052 		if (ret != ISCSI_HDR_LEN) {
4053 			iscsit_rx_thread_wait_for_tcp(conn);
4054 			break;
4055 		}
4056 
4057 		hdr = (struct iscsi_hdr *) buffer;
4058 		if (hdr->hlength) {
4059 			iov.iov_len = hdr->hlength * 4;
4060 			tmp_buf = krealloc(buffer,
4061 					  ISCSI_HDR_LEN + iov.iov_len,
4062 					  GFP_KERNEL);
4063 			if (!tmp_buf)
4064 				break;
4065 
4066 			buffer = tmp_buf;
4067 			iov.iov_base = &buffer[ISCSI_HDR_LEN];
4068 
4069 			ret = rx_data(conn, &iov, 1, iov.iov_len);
4070 			if (ret != iov.iov_len) {
4071 				iscsit_rx_thread_wait_for_tcp(conn);
4072 				break;
4073 			}
4074 		}
4075 
4076 		if (conn->conn_ops->HeaderDigest) {
4077 			iov.iov_base	= &digest;
4078 			iov.iov_len	= ISCSI_CRC_LEN;
4079 
4080 			ret = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
4081 			if (ret != ISCSI_CRC_LEN) {
4082 				iscsit_rx_thread_wait_for_tcp(conn);
4083 				break;
4084 			}
4085 
4086 			checksum = iscsit_crc_buf(buffer, ISCSI_HDR_LEN, 0,
4087 						  NULL);
4088 			if (digest != checksum) {
4089 				pr_err("HeaderDigest CRC32C failed,"
4090 					" received 0x%08x, computed 0x%08x\n",
4091 					digest, checksum);
4092 				/*
4093 				 * Set the PDU to 0xff so it will intentionally
4094 				 * hit default in the switch below.
4095 				 */
4096 				memset(buffer, 0xff, ISCSI_HDR_LEN);
4097 				atomic_long_inc(&conn->sess->conn_digest_errors);
4098 			} else {
4099 				pr_debug("Got HeaderDigest CRC32C"
4100 						" 0x%08x\n", checksum);
4101 			}
4102 		}
4103 
4104 		if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
4105 			break;
4106 
4107 		opcode = buffer[0] & ISCSI_OPCODE_MASK;
4108 
4109 		if (conn->sess->sess_ops->SessionType &&
4110 		   ((!(opcode & ISCSI_OP_TEXT)) ||
4111 		    (!(opcode & ISCSI_OP_LOGOUT)))) {
4112 			pr_err("Received illegal iSCSI Opcode: 0x%02x"
4113 			" while in Discovery Session, rejecting.\n", opcode);
4114 			iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
4115 					  buffer);
4116 			break;
4117 		}
4118 
4119 		ret = iscsi_target_rx_opcode(conn, buffer);
4120 		if (ret < 0)
4121 			break;
4122 	}
4123 
4124 	kfree(buffer);
4125 }
4126 
iscsi_target_rx_thread(void * arg)4127 int iscsi_target_rx_thread(void *arg)
4128 {
4129 	int rc;
4130 	struct iscsit_conn *conn = arg;
4131 	bool conn_freed = false;
4132 
4133 	/*
4134 	 * Allow ourselves to be interrupted by SIGINT so that a
4135 	 * connection recovery / failure event can be triggered externally.
4136 	 */
4137 	allow_signal(SIGINT);
4138 	/*
4139 	 * Wait for iscsi_post_login_handler() to complete before allowing
4140 	 * incoming iscsi/tcp socket I/O, and/or failing the connection.
4141 	 */
4142 	rc = wait_for_completion_interruptible(&conn->rx_login_comp);
4143 	if (rc < 0 || iscsi_target_check_conn_state(conn))
4144 		goto out;
4145 
4146 	if (!conn->conn_transport->iscsit_get_rx_pdu)
4147 		return 0;
4148 
4149 	conn->conn_transport->iscsit_get_rx_pdu(conn);
4150 
4151 	if (!signal_pending(current))
4152 		atomic_set(&conn->transport_failed, 1);
4153 	iscsit_take_action_for_connection_exit(conn, &conn_freed);
4154 
4155 out:
4156 	if (!conn_freed) {
4157 		while (!kthread_should_stop()) {
4158 			msleep(100);
4159 		}
4160 	}
4161 
4162 	return 0;
4163 }
4164 
iscsit_release_commands_from_conn(struct iscsit_conn * conn)4165 static void iscsit_release_commands_from_conn(struct iscsit_conn *conn)
4166 {
4167 	LIST_HEAD(tmp_list);
4168 	struct iscsit_cmd *cmd = NULL, *cmd_tmp = NULL;
4169 	struct iscsit_session *sess = conn->sess;
4170 	/*
4171 	 * We expect this function to only ever be called from either RX or TX
4172 	 * thread context via iscsit_close_connection() once the other context
4173 	 * has been reset -> returned sleeping pre-handler state.
4174 	 */
4175 	spin_lock_bh(&conn->cmd_lock);
4176 	list_splice_init(&conn->conn_cmd_list, &tmp_list);
4177 
4178 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4179 		struct se_cmd *se_cmd = &cmd->se_cmd;
4180 
4181 		if (!se_cmd->se_tfo)
4182 			continue;
4183 
4184 		spin_lock_irq(&se_cmd->t_state_lock);
4185 		if (se_cmd->transport_state & CMD_T_ABORTED) {
4186 			if (!(se_cmd->transport_state & CMD_T_TAS))
4187 				/*
4188 				 * LIO's abort path owns the cleanup for this,
4189 				 * so put it back on the list and let
4190 				 * aborted_task handle it.
4191 				 */
4192 				list_move_tail(&cmd->i_conn_node,
4193 					       &conn->conn_cmd_list);
4194 		} else {
4195 			se_cmd->transport_state |= CMD_T_FABRIC_STOP;
4196 		}
4197 
4198 		if (cmd->se_cmd.t_state == TRANSPORT_WRITE_PENDING) {
4199 			/*
4200 			 * We never submitted the cmd to LIO core, so we have
4201 			 * to tell LIO to perform the completion process.
4202 			 */
4203 			spin_unlock_irq(&se_cmd->t_state_lock);
4204 			target_complete_cmd(&cmd->se_cmd, SAM_STAT_TASK_ABORTED);
4205 			continue;
4206 		}
4207 		spin_unlock_irq(&se_cmd->t_state_lock);
4208 	}
4209 	spin_unlock_bh(&conn->cmd_lock);
4210 
4211 	list_for_each_entry_safe(cmd, cmd_tmp, &tmp_list, i_conn_node) {
4212 		list_del_init(&cmd->i_conn_node);
4213 
4214 		iscsit_increment_maxcmdsn(cmd, sess);
4215 		iscsit_free_cmd(cmd, true);
4216 
4217 	}
4218 
4219 	/*
4220 	 * Wait on commands that were cleaned up via the aborted_task path.
4221 	 * LLDs that implement iscsit_wait_conn will already have waited for
4222 	 * commands.
4223 	 */
4224 	if (!conn->conn_transport->iscsit_wait_conn) {
4225 		target_stop_cmd_counter(conn->cmd_cnt);
4226 		target_wait_for_cmds(conn->cmd_cnt);
4227 	}
4228 }
4229 
iscsit_stop_timers_for_cmds(struct iscsit_conn * conn)4230 static void iscsit_stop_timers_for_cmds(
4231 	struct iscsit_conn *conn)
4232 {
4233 	struct iscsit_cmd *cmd;
4234 
4235 	spin_lock_bh(&conn->cmd_lock);
4236 	list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
4237 		if (cmd->data_direction == DMA_TO_DEVICE)
4238 			iscsit_stop_dataout_timer(cmd);
4239 	}
4240 	spin_unlock_bh(&conn->cmd_lock);
4241 }
4242 
iscsit_close_connection(struct iscsit_conn * conn)4243 int iscsit_close_connection(
4244 	struct iscsit_conn *conn)
4245 {
4246 	int conn_logout = (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT);
4247 	struct iscsit_session	*sess = conn->sess;
4248 
4249 	pr_debug("Closing iSCSI connection CID %hu on SID:"
4250 		" %u\n", conn->cid, sess->sid);
4251 	/*
4252 	 * Always up conn_logout_comp for the traditional TCP and HW_OFFLOAD
4253 	 * case just in case the RX Thread in iscsi_target_rx_opcode() is
4254 	 * sleeping and the logout response never got sent because the
4255 	 * connection failed.
4256 	 *
4257 	 * However for iser-target, isert_wait4logout() is using conn_logout_comp
4258 	 * to signal logout response TX interrupt completion.  Go ahead and skip
4259 	 * this for iser since isert_rx_opcode() does not wait on logout failure,
4260 	 * and to avoid iscsit_conn pointer dereference in iser-target code.
4261 	 */
4262 	if (!conn->conn_transport->rdma_shutdown)
4263 		complete(&conn->conn_logout_comp);
4264 
4265 	if (!strcmp(current->comm, ISCSI_RX_THREAD_NAME)) {
4266 		if (conn->tx_thread &&
4267 		    cmpxchg(&conn->tx_thread_active, true, false)) {
4268 			send_sig(SIGINT, conn->tx_thread, 1);
4269 			kthread_stop(conn->tx_thread);
4270 		}
4271 	} else if (!strcmp(current->comm, ISCSI_TX_THREAD_NAME)) {
4272 		if (conn->rx_thread &&
4273 		    cmpxchg(&conn->rx_thread_active, true, false)) {
4274 			send_sig(SIGINT, conn->rx_thread, 1);
4275 			kthread_stop(conn->rx_thread);
4276 		}
4277 	}
4278 
4279 	spin_lock(&iscsit_global->ts_bitmap_lock);
4280 	bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
4281 			      get_order(1));
4282 	spin_unlock(&iscsit_global->ts_bitmap_lock);
4283 
4284 	iscsit_stop_timers_for_cmds(conn);
4285 	iscsit_stop_nopin_timer(conn);
4286 	iscsit_stop_nopin_response_timer(conn);
4287 
4288 	if (conn->conn_transport->iscsit_wait_conn)
4289 		conn->conn_transport->iscsit_wait_conn(conn);
4290 
4291 	/*
4292 	 * During Connection recovery drop unacknowledged out of order
4293 	 * commands for this connection, and prepare the other commands
4294 	 * for reallegiance.
4295 	 *
4296 	 * During normal operation clear the out of order commands (but
4297 	 * do not free the struct iscsi_ooo_cmdsn's) and release all
4298 	 * struct iscsit_cmds.
4299 	 */
4300 	if (atomic_read(&conn->connection_recovery)) {
4301 		iscsit_discard_unacknowledged_ooo_cmdsns_for_conn(conn);
4302 		iscsit_prepare_cmds_for_reallegiance(conn);
4303 	} else {
4304 		iscsit_clear_ooo_cmdsns_for_conn(conn);
4305 		iscsit_release_commands_from_conn(conn);
4306 	}
4307 	iscsit_free_queue_reqs_for_conn(conn);
4308 
4309 	/*
4310 	 * Handle decrementing session or connection usage count if
4311 	 * a logout response was not able to be sent because the
4312 	 * connection failed.  Fall back to Session Recovery here.
4313 	 */
4314 	if (atomic_read(&conn->conn_logout_remove)) {
4315 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_SESSION) {
4316 			iscsit_dec_conn_usage_count(conn);
4317 			iscsit_dec_session_usage_count(sess);
4318 		}
4319 		if (conn->conn_logout_reason == ISCSI_LOGOUT_REASON_CLOSE_CONNECTION)
4320 			iscsit_dec_conn_usage_count(conn);
4321 
4322 		atomic_set(&conn->conn_logout_remove, 0);
4323 		atomic_set(&sess->session_reinstatement, 0);
4324 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4325 	}
4326 
4327 	spin_lock_bh(&sess->conn_lock);
4328 	list_del(&conn->conn_list);
4329 
4330 	/*
4331 	 * Attempt to let the Initiator know this connection failed by
4332 	 * sending an Connection Dropped Async Message on another
4333 	 * active connection.
4334 	 */
4335 	if (atomic_read(&conn->connection_recovery))
4336 		iscsit_build_conn_drop_async_message(conn);
4337 
4338 	spin_unlock_bh(&sess->conn_lock);
4339 
4340 	/*
4341 	 * If connection reinstatement is being performed on this connection,
4342 	 * up the connection reinstatement semaphore that is being blocked on
4343 	 * in iscsit_cause_connection_reinstatement().
4344 	 */
4345 	spin_lock_bh(&conn->state_lock);
4346 	if (atomic_read(&conn->sleep_on_conn_wait_comp)) {
4347 		spin_unlock_bh(&conn->state_lock);
4348 		complete(&conn->conn_wait_comp);
4349 		wait_for_completion(&conn->conn_post_wait_comp);
4350 		spin_lock_bh(&conn->state_lock);
4351 	}
4352 
4353 	/*
4354 	 * If connection reinstatement is being performed on this connection
4355 	 * by receiving a REMOVECONNFORRECOVERY logout request, up the
4356 	 * connection wait rcfr semaphore that is being blocked on
4357 	 * an iscsit_connection_reinstatement_rcfr().
4358 	 */
4359 	if (atomic_read(&conn->connection_wait_rcfr)) {
4360 		spin_unlock_bh(&conn->state_lock);
4361 		complete(&conn->conn_wait_rcfr_comp);
4362 		wait_for_completion(&conn->conn_post_wait_comp);
4363 		spin_lock_bh(&conn->state_lock);
4364 	}
4365 	atomic_set(&conn->connection_reinstatement, 1);
4366 	spin_unlock_bh(&conn->state_lock);
4367 
4368 	/*
4369 	 * If any other processes are accessing this connection pointer we
4370 	 * must wait until they have completed.
4371 	 */
4372 	iscsit_check_conn_usage_count(conn);
4373 
4374 	if (conn->sock)
4375 		sock_release(conn->sock);
4376 
4377 	if (conn->conn_transport->iscsit_free_conn)
4378 		conn->conn_transport->iscsit_free_conn(conn);
4379 
4380 	pr_debug("Moving to TARG_CONN_STATE_FREE.\n");
4381 	conn->conn_state = TARG_CONN_STATE_FREE;
4382 	iscsit_free_conn(conn);
4383 
4384 	spin_lock_bh(&sess->conn_lock);
4385 	atomic_dec(&sess->nconn);
4386 	pr_debug("Decremented iSCSI connection count to %d from node:"
4387 		" %s\n", atomic_read(&sess->nconn),
4388 		sess->sess_ops->InitiatorName);
4389 	/*
4390 	 * Make sure that if one connection fails in an non ERL=2 iSCSI
4391 	 * Session that they all fail.
4392 	 */
4393 	if ((sess->sess_ops->ErrorRecoveryLevel != 2) && !conn_logout &&
4394 	     !atomic_read(&sess->session_logout))
4395 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4396 
4397 	/*
4398 	 * If this was not the last connection in the session, and we are
4399 	 * performing session reinstatement or falling back to ERL=0, call
4400 	 * iscsit_stop_session() without sleeping to shutdown the other
4401 	 * active connections.
4402 	 */
4403 	if (atomic_read(&sess->nconn)) {
4404 		if (!atomic_read(&sess->session_reinstatement) &&
4405 		    !atomic_read(&sess->session_fall_back_to_erl0)) {
4406 			spin_unlock_bh(&sess->conn_lock);
4407 			return 0;
4408 		}
4409 		if (!atomic_read(&sess->session_stop_active)) {
4410 			atomic_set(&sess->session_stop_active, 1);
4411 			spin_unlock_bh(&sess->conn_lock);
4412 			iscsit_stop_session(sess, 0, 0);
4413 			return 0;
4414 		}
4415 		spin_unlock_bh(&sess->conn_lock);
4416 		return 0;
4417 	}
4418 
4419 	/*
4420 	 * If this was the last connection in the session and one of the
4421 	 * following is occurring:
4422 	 *
4423 	 * Session Reinstatement is not being performed, and are falling back
4424 	 * to ERL=0 call iscsit_close_session().
4425 	 *
4426 	 * Session Logout was requested.  iscsit_close_session() will be called
4427 	 * elsewhere.
4428 	 *
4429 	 * Session Continuation is not being performed, start the Time2Retain
4430 	 * handler and check if sleep_on_sess_wait_sem is active.
4431 	 */
4432 	if (!atomic_read(&sess->session_reinstatement) &&
4433 	     atomic_read(&sess->session_fall_back_to_erl0)) {
4434 		spin_unlock_bh(&sess->conn_lock);
4435 		complete_all(&sess->session_wait_comp);
4436 		iscsit_close_session(sess, true);
4437 
4438 		return 0;
4439 	} else if (atomic_read(&sess->session_logout)) {
4440 		pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4441 		sess->session_state = TARG_SESS_STATE_FREE;
4442 
4443 		if (atomic_read(&sess->session_close)) {
4444 			spin_unlock_bh(&sess->conn_lock);
4445 			complete_all(&sess->session_wait_comp);
4446 			iscsit_close_session(sess, true);
4447 		} else {
4448 			spin_unlock_bh(&sess->conn_lock);
4449 		}
4450 
4451 		return 0;
4452 	} else {
4453 		pr_debug("Moving to TARG_SESS_STATE_FAILED.\n");
4454 		sess->session_state = TARG_SESS_STATE_FAILED;
4455 
4456 		if (!atomic_read(&sess->session_continuation))
4457 			iscsit_start_time2retain_handler(sess);
4458 
4459 		if (atomic_read(&sess->session_close)) {
4460 			spin_unlock_bh(&sess->conn_lock);
4461 			complete_all(&sess->session_wait_comp);
4462 			iscsit_close_session(sess, true);
4463 		} else {
4464 			spin_unlock_bh(&sess->conn_lock);
4465 		}
4466 
4467 		return 0;
4468 	}
4469 }
4470 
4471 /*
4472  * If the iSCSI Session for the iSCSI Initiator Node exists,
4473  * forcefully shutdown the iSCSI NEXUS.
4474  */
iscsit_close_session(struct iscsit_session * sess,bool can_sleep)4475 int iscsit_close_session(struct iscsit_session *sess, bool can_sleep)
4476 {
4477 	struct iscsi_portal_group *tpg = sess->tpg;
4478 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4479 
4480 	if (atomic_read(&sess->nconn)) {
4481 		pr_err("%d connection(s) still exist for iSCSI session"
4482 			" to %s\n", atomic_read(&sess->nconn),
4483 			sess->sess_ops->InitiatorName);
4484 		BUG();
4485 	}
4486 
4487 	spin_lock_bh(&se_tpg->session_lock);
4488 	atomic_set(&sess->session_logout, 1);
4489 	atomic_set(&sess->session_reinstatement, 1);
4490 	iscsit_stop_time2retain_timer(sess);
4491 	spin_unlock_bh(&se_tpg->session_lock);
4492 
4493 	if (sess->sess_ops->ErrorRecoveryLevel == 2)
4494 		iscsit_free_connection_recovery_entries(sess);
4495 
4496 	/*
4497 	 * transport_deregister_session_configfs() will clear the
4498 	 * struct se_node_acl->nacl_sess pointer now as a iscsi_np process context
4499 	 * can be setting it again with __transport_register_session() in
4500 	 * iscsi_post_login_handler() again after the iscsit_stop_session()
4501 	 * completes in iscsi_np context.
4502 	 */
4503 	transport_deregister_session_configfs(sess->se_sess);
4504 
4505 	/*
4506 	 * If any other processes are accessing this session pointer we must
4507 	 * wait until they have completed.  If we are in an interrupt (the
4508 	 * time2retain handler) and contain and active session usage count we
4509 	 * restart the timer and exit.
4510 	 */
4511 	if (iscsit_check_session_usage_count(sess, can_sleep)) {
4512 		atomic_set(&sess->session_logout, 0);
4513 		iscsit_start_time2retain_handler(sess);
4514 		return 0;
4515 	}
4516 
4517 	transport_deregister_session(sess->se_sess);
4518 
4519 	iscsit_free_all_ooo_cmdsns(sess);
4520 
4521 	spin_lock_bh(&se_tpg->session_lock);
4522 	pr_debug("Moving to TARG_SESS_STATE_FREE.\n");
4523 	sess->session_state = TARG_SESS_STATE_FREE;
4524 	pr_debug("Released iSCSI session from node: %s\n",
4525 			sess->sess_ops->InitiatorName);
4526 	tpg->nsessions--;
4527 	if (tpg->tpg_tiqn)
4528 		tpg->tpg_tiqn->tiqn_nsessions--;
4529 
4530 	pr_debug("Decremented number of active iSCSI Sessions on"
4531 		" iSCSI TPG: %hu to %u\n", tpg->tpgt, tpg->nsessions);
4532 
4533 	ida_free(&sess_ida, sess->session_index);
4534 	kfree(sess->sess_ops);
4535 	sess->sess_ops = NULL;
4536 	spin_unlock_bh(&se_tpg->session_lock);
4537 
4538 	kfree(sess);
4539 	return 0;
4540 }
4541 
iscsit_logout_post_handler_closesession(struct iscsit_conn * conn)4542 static void iscsit_logout_post_handler_closesession(
4543 	struct iscsit_conn *conn)
4544 {
4545 	struct iscsit_session *sess = conn->sess;
4546 	int sleep = 1;
4547 	/*
4548 	 * Traditional iscsi/tcp will invoke this logic from TX thread
4549 	 * context during session logout, so clear tx_thread_active and
4550 	 * sleep if iscsit_close_connection() has not already occured.
4551 	 *
4552 	 * Since iser-target invokes this logic from it's own workqueue,
4553 	 * always sleep waiting for RX/TX thread shutdown to complete
4554 	 * within iscsit_close_connection().
4555 	 */
4556 	if (!conn->conn_transport->rdma_shutdown) {
4557 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4558 		if (!sleep)
4559 			return;
4560 	}
4561 
4562 	atomic_set(&conn->conn_logout_remove, 0);
4563 	complete(&conn->conn_logout_comp);
4564 
4565 	iscsit_dec_conn_usage_count(conn);
4566 	atomic_set(&sess->session_close, 1);
4567 	iscsit_stop_session(sess, sleep, sleep);
4568 	iscsit_dec_session_usage_count(sess);
4569 }
4570 
iscsit_logout_post_handler_samecid(struct iscsit_conn * conn)4571 static void iscsit_logout_post_handler_samecid(
4572 	struct iscsit_conn *conn)
4573 {
4574 	int sleep = 1;
4575 
4576 	if (!conn->conn_transport->rdma_shutdown) {
4577 		sleep = cmpxchg(&conn->tx_thread_active, true, false);
4578 		if (!sleep)
4579 			return;
4580 	}
4581 
4582 	atomic_set(&conn->conn_logout_remove, 0);
4583 	complete(&conn->conn_logout_comp);
4584 
4585 	iscsit_cause_connection_reinstatement(conn, sleep);
4586 	iscsit_dec_conn_usage_count(conn);
4587 }
4588 
iscsit_logout_post_handler_diffcid(struct iscsit_conn * conn,u16 cid)4589 static void iscsit_logout_post_handler_diffcid(
4590 	struct iscsit_conn *conn,
4591 	u16 cid)
4592 {
4593 	struct iscsit_conn *l_conn;
4594 	struct iscsit_session *sess = conn->sess;
4595 	bool conn_found = false;
4596 
4597 	if (!sess)
4598 		return;
4599 
4600 	spin_lock_bh(&sess->conn_lock);
4601 	list_for_each_entry(l_conn, &sess->sess_conn_list, conn_list) {
4602 		if (l_conn->cid == cid) {
4603 			iscsit_inc_conn_usage_count(l_conn);
4604 			conn_found = true;
4605 			break;
4606 		}
4607 	}
4608 	spin_unlock_bh(&sess->conn_lock);
4609 
4610 	if (!conn_found)
4611 		return;
4612 
4613 	if (l_conn->sock)
4614 		l_conn->sock->ops->shutdown(l_conn->sock, RCV_SHUTDOWN);
4615 
4616 	spin_lock_bh(&l_conn->state_lock);
4617 	pr_debug("Moving to TARG_CONN_STATE_IN_LOGOUT.\n");
4618 	l_conn->conn_state = TARG_CONN_STATE_IN_LOGOUT;
4619 	spin_unlock_bh(&l_conn->state_lock);
4620 
4621 	iscsit_cause_connection_reinstatement(l_conn, 1);
4622 	iscsit_dec_conn_usage_count(l_conn);
4623 }
4624 
4625 /*
4626  *	Return of 0 causes the TX thread to restart.
4627  */
iscsit_logout_post_handler(struct iscsit_cmd * cmd,struct iscsit_conn * conn)4628 int iscsit_logout_post_handler(
4629 	struct iscsit_cmd *cmd,
4630 	struct iscsit_conn *conn)
4631 {
4632 	int ret = 0;
4633 
4634 	switch (cmd->logout_reason) {
4635 	case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
4636 		switch (cmd->logout_response) {
4637 		case ISCSI_LOGOUT_SUCCESS:
4638 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4639 		default:
4640 			iscsit_logout_post_handler_closesession(conn);
4641 			break;
4642 		}
4643 		break;
4644 	case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
4645 		if (conn->cid == cmd->logout_cid) {
4646 			switch (cmd->logout_response) {
4647 			case ISCSI_LOGOUT_SUCCESS:
4648 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4649 			default:
4650 				iscsit_logout_post_handler_samecid(conn);
4651 				break;
4652 			}
4653 		} else {
4654 			switch (cmd->logout_response) {
4655 			case ISCSI_LOGOUT_SUCCESS:
4656 				iscsit_logout_post_handler_diffcid(conn,
4657 					cmd->logout_cid);
4658 				break;
4659 			case ISCSI_LOGOUT_CID_NOT_FOUND:
4660 			case ISCSI_LOGOUT_CLEANUP_FAILED:
4661 			default:
4662 				break;
4663 			}
4664 			ret = 1;
4665 		}
4666 		break;
4667 	case ISCSI_LOGOUT_REASON_RECOVERY:
4668 		switch (cmd->logout_response) {
4669 		case ISCSI_LOGOUT_SUCCESS:
4670 		case ISCSI_LOGOUT_CID_NOT_FOUND:
4671 		case ISCSI_LOGOUT_RECOVERY_UNSUPPORTED:
4672 		case ISCSI_LOGOUT_CLEANUP_FAILED:
4673 		default:
4674 			break;
4675 		}
4676 		ret = 1;
4677 		break;
4678 	default:
4679 		break;
4680 
4681 	}
4682 	return ret;
4683 }
4684 EXPORT_SYMBOL(iscsit_logout_post_handler);
4685 
iscsit_stop_session(struct iscsit_session * sess,int session_sleep,int connection_sleep)4686 void iscsit_stop_session(
4687 	struct iscsit_session *sess,
4688 	int session_sleep,
4689 	int connection_sleep)
4690 {
4691 	u16 conn_count = atomic_read(&sess->nconn);
4692 	struct iscsit_conn *conn, *conn_tmp = NULL;
4693 	int is_last;
4694 
4695 	spin_lock_bh(&sess->conn_lock);
4696 
4697 	if (connection_sleep) {
4698 		list_for_each_entry_safe(conn, conn_tmp, &sess->sess_conn_list,
4699 				conn_list) {
4700 			if (conn_count == 0)
4701 				break;
4702 
4703 			if (list_is_last(&conn->conn_list, &sess->sess_conn_list)) {
4704 				is_last = 1;
4705 			} else {
4706 				iscsit_inc_conn_usage_count(conn_tmp);
4707 				is_last = 0;
4708 			}
4709 			iscsit_inc_conn_usage_count(conn);
4710 
4711 			spin_unlock_bh(&sess->conn_lock);
4712 			iscsit_cause_connection_reinstatement(conn, 1);
4713 			spin_lock_bh(&sess->conn_lock);
4714 
4715 			iscsit_dec_conn_usage_count(conn);
4716 			if (is_last == 0)
4717 				iscsit_dec_conn_usage_count(conn_tmp);
4718 			conn_count--;
4719 		}
4720 	} else {
4721 		list_for_each_entry(conn, &sess->sess_conn_list, conn_list)
4722 			iscsit_cause_connection_reinstatement(conn, 0);
4723 	}
4724 
4725 	if (session_sleep && atomic_read(&sess->nconn)) {
4726 		spin_unlock_bh(&sess->conn_lock);
4727 		wait_for_completion(&sess->session_wait_comp);
4728 	} else
4729 		spin_unlock_bh(&sess->conn_lock);
4730 }
4731 
iscsit_release_sessions_for_tpg(struct iscsi_portal_group * tpg,int force)4732 int iscsit_release_sessions_for_tpg(struct iscsi_portal_group *tpg, int force)
4733 {
4734 	struct iscsit_session *sess;
4735 	struct se_portal_group *se_tpg = &tpg->tpg_se_tpg;
4736 	struct se_session *se_sess, *se_sess_tmp;
4737 	LIST_HEAD(free_list);
4738 	int session_count = 0;
4739 
4740 	spin_lock_bh(&se_tpg->session_lock);
4741 	if (tpg->nsessions && !force) {
4742 		spin_unlock_bh(&se_tpg->session_lock);
4743 		return -1;
4744 	}
4745 
4746 	list_for_each_entry_safe(se_sess, se_sess_tmp, &se_tpg->tpg_sess_list,
4747 			sess_list) {
4748 		sess = (struct iscsit_session *)se_sess->fabric_sess_ptr;
4749 
4750 		spin_lock(&sess->conn_lock);
4751 		if (atomic_read(&sess->session_fall_back_to_erl0) ||
4752 		    atomic_read(&sess->session_logout) ||
4753 		    atomic_read(&sess->session_close) ||
4754 		    (sess->time2retain_timer_flags & ISCSI_TF_EXPIRED)) {
4755 			spin_unlock(&sess->conn_lock);
4756 			continue;
4757 		}
4758 		iscsit_inc_session_usage_count(sess);
4759 		atomic_set(&sess->session_reinstatement, 1);
4760 		atomic_set(&sess->session_fall_back_to_erl0, 1);
4761 		atomic_set(&sess->session_close, 1);
4762 		spin_unlock(&sess->conn_lock);
4763 
4764 		list_move_tail(&se_sess->sess_list, &free_list);
4765 	}
4766 	spin_unlock_bh(&se_tpg->session_lock);
4767 
4768 	list_for_each_entry_safe(se_sess, se_sess_tmp, &free_list, sess_list) {
4769 		sess = (struct iscsit_session *)se_sess->fabric_sess_ptr;
4770 
4771 		list_del_init(&se_sess->sess_list);
4772 		iscsit_stop_session(sess, 1, 1);
4773 		iscsit_dec_session_usage_count(sess);
4774 		session_count++;
4775 	}
4776 
4777 	pr_debug("Released %d iSCSI Session(s) from Target Portal"
4778 			" Group: %hu\n", session_count, tpg->tpgt);
4779 	return 0;
4780 }
4781 
4782 MODULE_DESCRIPTION("iSCSI-Target Driver for mainline target infrastructure");
4783 MODULE_VERSION("4.1.x");
4784 MODULE_AUTHOR("nab@Linux-iSCSI.org");
4785 MODULE_LICENSE("GPL");
4786 
4787 module_init(iscsi_target_init_module);
4788 module_exit(iscsi_target_cleanup_module);
4789