1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*******************************************************************************
3  * Filename:  target_core_device.c (based on iscsi_target_device.c)
4  *
5  * This file contains the TCM Virtual Device and Disk Transport
6  * agnostic related functions.
7  *
8  * (c) Copyright 2003-2013 Datera, Inc.
9  *
10  * Nicholas A. Bellinger <nab@kernel.org>
11  *
12  ******************************************************************************/
13 
14 #include <linux/net.h>
15 #include <linux/string.h>
16 #include <linux/delay.h>
17 #include <linux/timer.h>
18 #include <linux/slab.h>
19 #include <linux/spinlock.h>
20 #include <linux/kthread.h>
21 #include <linux/in.h>
22 #include <linux/export.h>
23 #include <linux/t10-pi.h>
24 #include <asm/unaligned.h>
25 #include <net/sock.h>
26 #include <net/tcp.h>
27 #include <scsi/scsi_common.h>
28 #include <scsi/scsi_proto.h>
29 
30 #include <target/target_core_base.h>
31 #include <target/target_core_backend.h>
32 #include <target/target_core_fabric.h>
33 
34 #include "target_core_internal.h"
35 #include "target_core_alua.h"
36 #include "target_core_pr.h"
37 #include "target_core_ua.h"
38 
39 static DEFINE_MUTEX(device_mutex);
40 static LIST_HEAD(device_list);
41 static DEFINE_IDR(devices_idr);
42 
43 static struct se_hba *lun0_hba;
44 /* not static, needed by tpg.c */
45 struct se_device *g_lun0_dev;
46 
47 sense_reason_t
48 transport_lookup_cmd_lun(struct se_cmd *se_cmd)
49 {
50 	struct se_lun *se_lun = NULL;
51 	struct se_session *se_sess = se_cmd->se_sess;
52 	struct se_node_acl *nacl = se_sess->se_node_acl;
53 	struct se_dev_entry *deve;
54 	sense_reason_t ret = TCM_NO_SENSE;
55 
56 	rcu_read_lock();
57 	deve = target_nacl_find_deve(nacl, se_cmd->orig_fe_lun);
58 	if (deve) {
59 		atomic_long_inc(&deve->total_cmds);
60 
61 		if (se_cmd->data_direction == DMA_TO_DEVICE)
62 			atomic_long_add(se_cmd->data_length,
63 					&deve->write_bytes);
64 		else if (se_cmd->data_direction == DMA_FROM_DEVICE)
65 			atomic_long_add(se_cmd->data_length,
66 					&deve->read_bytes);
67 
68 		if ((se_cmd->data_direction == DMA_TO_DEVICE) &&
69 		    deve->lun_access_ro) {
70 			pr_err("TARGET_CORE[%s]: Detected WRITE_PROTECTED LUN"
71 				" Access for 0x%08llx\n",
72 				se_cmd->se_tfo->fabric_name,
73 				se_cmd->orig_fe_lun);
74 			rcu_read_unlock();
75 			return TCM_WRITE_PROTECTED;
76 		}
77 
78 		se_lun = deve->se_lun;
79 
80 		if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {
81 			se_lun = NULL;
82 			goto out_unlock;
83 		}
84 
85 		se_cmd->se_lun = se_lun;
86 		se_cmd->pr_res_key = deve->pr_res_key;
87 		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
88 		se_cmd->lun_ref_active = true;
89 	}
90 out_unlock:
91 	rcu_read_unlock();
92 
93 	if (!se_lun) {
94 		/*
95 		 * Use the se_portal_group->tpg_virt_lun0 to allow for
96 		 * REPORT_LUNS, et al to be returned when no active
97 		 * MappedLUN=0 exists for this Initiator Port.
98 		 */
99 		if (se_cmd->orig_fe_lun != 0) {
100 			pr_err("TARGET_CORE[%s]: Detected NON_EXISTENT_LUN"
101 				" Access for 0x%08llx from %s\n",
102 				se_cmd->se_tfo->fabric_name,
103 				se_cmd->orig_fe_lun,
104 				nacl->initiatorname);
105 			return TCM_NON_EXISTENT_LUN;
106 		}
107 
108 		/*
109 		 * Force WRITE PROTECT for virtual LUN 0
110 		 */
111 		if ((se_cmd->data_direction != DMA_FROM_DEVICE) &&
112 		    (se_cmd->data_direction != DMA_NONE))
113 			return TCM_WRITE_PROTECTED;
114 
115 		se_lun = se_sess->se_tpg->tpg_virt_lun0;
116 		if (!percpu_ref_tryget_live(&se_lun->lun_ref))
117 			return TCM_NON_EXISTENT_LUN;
118 
119 		se_cmd->se_lun = se_sess->se_tpg->tpg_virt_lun0;
120 		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
121 		se_cmd->lun_ref_active = true;
122 	}
123 	/*
124 	 * RCU reference protected by percpu se_lun->lun_ref taken above that
125 	 * must drop to zero (including initial reference) before this se_lun
126 	 * pointer can be kfree_rcu() by the final se_lun->lun_group put via
127 	 * target_core_fabric_configfs.c:target_fabric_port_release
128 	 */
129 	se_cmd->se_dev = rcu_dereference_raw(se_lun->lun_se_dev);
130 	atomic_long_inc(&se_cmd->se_dev->num_cmds);
131 
132 	if (se_cmd->data_direction == DMA_TO_DEVICE)
133 		atomic_long_add(se_cmd->data_length,
134 				&se_cmd->se_dev->write_bytes);
135 	else if (se_cmd->data_direction == DMA_FROM_DEVICE)
136 		atomic_long_add(se_cmd->data_length,
137 				&se_cmd->se_dev->read_bytes);
138 
139 	return ret;
140 }
141 EXPORT_SYMBOL(transport_lookup_cmd_lun);
142 
143 int transport_lookup_tmr_lun(struct se_cmd *se_cmd)
144 {
145 	struct se_dev_entry *deve;
146 	struct se_lun *se_lun = NULL;
147 	struct se_session *se_sess = se_cmd->se_sess;
148 	struct se_node_acl *nacl = se_sess->se_node_acl;
149 	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
150 	unsigned long flags;
151 
152 	rcu_read_lock();
153 	deve = target_nacl_find_deve(nacl, se_cmd->orig_fe_lun);
154 	if (deve) {
155 		se_lun = deve->se_lun;
156 
157 		if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {
158 			se_lun = NULL;
159 			goto out_unlock;
160 		}
161 
162 		se_cmd->se_lun = se_lun;
163 		se_cmd->pr_res_key = deve->pr_res_key;
164 		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
165 		se_cmd->lun_ref_active = true;
166 	}
167 out_unlock:
168 	rcu_read_unlock();
169 
170 	if (!se_lun) {
171 		pr_debug("TARGET_CORE[%s]: Detected NON_EXISTENT_LUN"
172 			" Access for 0x%08llx for %s\n",
173 			se_cmd->se_tfo->fabric_name,
174 			se_cmd->orig_fe_lun,
175 			nacl->initiatorname);
176 		return -ENODEV;
177 	}
178 	se_cmd->se_dev = rcu_dereference_raw(se_lun->lun_se_dev);
179 	se_tmr->tmr_dev = rcu_dereference_raw(se_lun->lun_se_dev);
180 
181 	spin_lock_irqsave(&se_tmr->tmr_dev->se_tmr_lock, flags);
182 	list_add_tail(&se_tmr->tmr_list, &se_tmr->tmr_dev->dev_tmr_list);
183 	spin_unlock_irqrestore(&se_tmr->tmr_dev->se_tmr_lock, flags);
184 
185 	return 0;
186 }
187 EXPORT_SYMBOL(transport_lookup_tmr_lun);
188 
189 bool target_lun_is_rdonly(struct se_cmd *cmd)
190 {
191 	struct se_session *se_sess = cmd->se_sess;
192 	struct se_dev_entry *deve;
193 	bool ret;
194 
195 	rcu_read_lock();
196 	deve = target_nacl_find_deve(se_sess->se_node_acl, cmd->orig_fe_lun);
197 	ret = deve && deve->lun_access_ro;
198 	rcu_read_unlock();
199 
200 	return ret;
201 }
202 EXPORT_SYMBOL(target_lun_is_rdonly);
203 
204 /*
205  * This function is called from core_scsi3_emulate_pro_register_and_move()
206  * and core_scsi3_decode_spec_i_port(), and will increment &deve->pr_kref
207  * when a matching rtpi is found.
208  */
209 struct se_dev_entry *core_get_se_deve_from_rtpi(
210 	struct se_node_acl *nacl,
211 	u16 rtpi)
212 {
213 	struct se_dev_entry *deve;
214 	struct se_lun *lun;
215 	struct se_portal_group *tpg = nacl->se_tpg;
216 
217 	rcu_read_lock();
218 	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
219 		lun = deve->se_lun;
220 		if (!lun) {
221 			pr_err("%s device entries device pointer is"
222 				" NULL, but Initiator has access.\n",
223 				tpg->se_tpg_tfo->fabric_name);
224 			continue;
225 		}
226 		if (lun->lun_rtpi != rtpi)
227 			continue;
228 
229 		kref_get(&deve->pr_kref);
230 		rcu_read_unlock();
231 
232 		return deve;
233 	}
234 	rcu_read_unlock();
235 
236 	return NULL;
237 }
238 
239 void core_free_device_list_for_node(
240 	struct se_node_acl *nacl,
241 	struct se_portal_group *tpg)
242 {
243 	struct se_dev_entry *deve;
244 
245 	mutex_lock(&nacl->lun_entry_mutex);
246 	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)
247 		core_disable_device_list_for_node(deve->se_lun, deve, nacl, tpg);
248 	mutex_unlock(&nacl->lun_entry_mutex);
249 }
250 
251 void core_update_device_list_access(
252 	u64 mapped_lun,
253 	bool lun_access_ro,
254 	struct se_node_acl *nacl)
255 {
256 	struct se_dev_entry *deve;
257 
258 	mutex_lock(&nacl->lun_entry_mutex);
259 	deve = target_nacl_find_deve(nacl, mapped_lun);
260 	if (deve)
261 		deve->lun_access_ro = lun_access_ro;
262 	mutex_unlock(&nacl->lun_entry_mutex);
263 }
264 
265 /*
266  * Called with rcu_read_lock or nacl->device_list_lock held.
267  */
268 struct se_dev_entry *target_nacl_find_deve(struct se_node_acl *nacl, u64 mapped_lun)
269 {
270 	struct se_dev_entry *deve;
271 
272 	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)
273 		if (deve->mapped_lun == mapped_lun)
274 			return deve;
275 
276 	return NULL;
277 }
278 EXPORT_SYMBOL(target_nacl_find_deve);
279 
280 void target_pr_kref_release(struct kref *kref)
281 {
282 	struct se_dev_entry *deve = container_of(kref, struct se_dev_entry,
283 						 pr_kref);
284 	complete(&deve->pr_comp);
285 }
286 
287 /*
288  * Establish UA condition on SCSI device - all LUNs
289  */
290 void target_dev_ua_allocate(struct se_device *dev, u8 asc, u8 ascq)
291 {
292 	struct se_dev_entry *se_deve;
293 	struct se_lun *lun;
294 
295 	spin_lock(&dev->se_port_lock);
296 	list_for_each_entry(lun, &dev->dev_sep_list, lun_dev_link) {
297 
298 		spin_lock(&lun->lun_deve_lock);
299 		list_for_each_entry(se_deve, &lun->lun_deve_list, lun_link)
300 			core_scsi3_ua_allocate(se_deve, asc, ascq);
301 		spin_unlock(&lun->lun_deve_lock);
302 	}
303 	spin_unlock(&dev->se_port_lock);
304 }
305 
306 static void
307 target_luns_data_has_changed(struct se_node_acl *nacl, struct se_dev_entry *new,
308 			     bool skip_new)
309 {
310 	struct se_dev_entry *tmp;
311 
312 	rcu_read_lock();
313 	hlist_for_each_entry_rcu(tmp, &nacl->lun_entry_hlist, link) {
314 		if (skip_new && tmp == new)
315 			continue;
316 		core_scsi3_ua_allocate(tmp, 0x3F,
317 				       ASCQ_3FH_REPORTED_LUNS_DATA_HAS_CHANGED);
318 	}
319 	rcu_read_unlock();
320 }
321 
322 int core_enable_device_list_for_node(
323 	struct se_lun *lun,
324 	struct se_lun_acl *lun_acl,
325 	u64 mapped_lun,
326 	bool lun_access_ro,
327 	struct se_node_acl *nacl,
328 	struct se_portal_group *tpg)
329 {
330 	struct se_dev_entry *orig, *new;
331 
332 	new = kzalloc(sizeof(*new), GFP_KERNEL);
333 	if (!new) {
334 		pr_err("Unable to allocate se_dev_entry memory\n");
335 		return -ENOMEM;
336 	}
337 
338 	spin_lock_init(&new->ua_lock);
339 	INIT_LIST_HEAD(&new->ua_list);
340 	INIT_LIST_HEAD(&new->lun_link);
341 
342 	new->mapped_lun = mapped_lun;
343 	kref_init(&new->pr_kref);
344 	init_completion(&new->pr_comp);
345 
346 	new->lun_access_ro = lun_access_ro;
347 	new->creation_time = get_jiffies_64();
348 	new->attach_count++;
349 
350 	mutex_lock(&nacl->lun_entry_mutex);
351 	orig = target_nacl_find_deve(nacl, mapped_lun);
352 	if (orig && orig->se_lun) {
353 		struct se_lun *orig_lun = orig->se_lun;
354 
355 		if (orig_lun != lun) {
356 			pr_err("Existing orig->se_lun doesn't match new lun"
357 			       " for dynamic -> explicit NodeACL conversion:"
358 				" %s\n", nacl->initiatorname);
359 			mutex_unlock(&nacl->lun_entry_mutex);
360 			kfree(new);
361 			return -EINVAL;
362 		}
363 		if (orig->se_lun_acl != NULL) {
364 			pr_warn_ratelimited("Detected existing explicit"
365 				" se_lun_acl->se_lun_group reference for %s"
366 				" mapped_lun: %llu, failing\n",
367 				 nacl->initiatorname, mapped_lun);
368 			mutex_unlock(&nacl->lun_entry_mutex);
369 			kfree(new);
370 			return -EINVAL;
371 		}
372 
373 		new->se_lun = lun;
374 		new->se_lun_acl = lun_acl;
375 		hlist_del_rcu(&orig->link);
376 		hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);
377 		mutex_unlock(&nacl->lun_entry_mutex);
378 
379 		spin_lock(&lun->lun_deve_lock);
380 		list_del(&orig->lun_link);
381 		list_add_tail(&new->lun_link, &lun->lun_deve_list);
382 		spin_unlock(&lun->lun_deve_lock);
383 
384 		kref_put(&orig->pr_kref, target_pr_kref_release);
385 		wait_for_completion(&orig->pr_comp);
386 
387 		target_luns_data_has_changed(nacl, new, true);
388 		kfree_rcu(orig, rcu_head);
389 		return 0;
390 	}
391 
392 	new->se_lun = lun;
393 	new->se_lun_acl = lun_acl;
394 	hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);
395 	mutex_unlock(&nacl->lun_entry_mutex);
396 
397 	spin_lock(&lun->lun_deve_lock);
398 	list_add_tail(&new->lun_link, &lun->lun_deve_list);
399 	spin_unlock(&lun->lun_deve_lock);
400 
401 	target_luns_data_has_changed(nacl, new, true);
402 	return 0;
403 }
404 
405 void core_disable_device_list_for_node(
406 	struct se_lun *lun,
407 	struct se_dev_entry *orig,
408 	struct se_node_acl *nacl,
409 	struct se_portal_group *tpg)
410 {
411 	/*
412 	 * rcu_dereference_raw protected by se_lun->lun_group symlink
413 	 * reference to se_device->dev_group.
414 	 */
415 	struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
416 
417 	lockdep_assert_held(&nacl->lun_entry_mutex);
418 
419 	/*
420 	 * If the MappedLUN entry is being disabled, the entry in
421 	 * lun->lun_deve_list must be removed now before clearing the
422 	 * struct se_dev_entry pointers below as logic in
423 	 * core_alua_do_transition_tg_pt() depends on these being present.
424 	 *
425 	 * deve->se_lun_acl will be NULL for demo-mode created LUNs
426 	 * that have not been explicitly converted to MappedLUNs ->
427 	 * struct se_lun_acl, but we remove deve->lun_link from
428 	 * lun->lun_deve_list. This also means that active UAs and
429 	 * NodeACL context specific PR metadata for demo-mode
430 	 * MappedLUN *deve will be released below..
431 	 */
432 	spin_lock(&lun->lun_deve_lock);
433 	list_del(&orig->lun_link);
434 	spin_unlock(&lun->lun_deve_lock);
435 	/*
436 	 * Disable struct se_dev_entry LUN ACL mapping
437 	 */
438 	core_scsi3_ua_release_all(orig);
439 
440 	hlist_del_rcu(&orig->link);
441 	clear_bit(DEF_PR_REG_ACTIVE, &orig->deve_flags);
442 	orig->lun_access_ro = false;
443 	orig->creation_time = 0;
444 	orig->attach_count--;
445 	/*
446 	 * Before firing off RCU callback, wait for any in process SPEC_I_PT=1
447 	 * or REGISTER_AND_MOVE PR operation to complete.
448 	 */
449 	kref_put(&orig->pr_kref, target_pr_kref_release);
450 	wait_for_completion(&orig->pr_comp);
451 
452 	kfree_rcu(orig, rcu_head);
453 
454 	core_scsi3_free_pr_reg_from_nacl(dev, nacl);
455 	target_luns_data_has_changed(nacl, NULL, false);
456 }
457 
458 /*      core_clear_lun_from_tpg():
459  *
460  *
461  */
462 void core_clear_lun_from_tpg(struct se_lun *lun, struct se_portal_group *tpg)
463 {
464 	struct se_node_acl *nacl;
465 	struct se_dev_entry *deve;
466 
467 	mutex_lock(&tpg->acl_node_mutex);
468 	list_for_each_entry(nacl, &tpg->acl_node_list, acl_list) {
469 
470 		mutex_lock(&nacl->lun_entry_mutex);
471 		hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
472 			if (lun != deve->se_lun)
473 				continue;
474 
475 			core_disable_device_list_for_node(lun, deve, nacl, tpg);
476 		}
477 		mutex_unlock(&nacl->lun_entry_mutex);
478 	}
479 	mutex_unlock(&tpg->acl_node_mutex);
480 }
481 
482 int core_alloc_rtpi(struct se_lun *lun, struct se_device *dev)
483 {
484 	struct se_lun *tmp;
485 
486 	spin_lock(&dev->se_port_lock);
487 	if (dev->export_count == 0x0000ffff) {
488 		pr_warn("Reached dev->dev_port_count =="
489 				" 0x0000ffff\n");
490 		spin_unlock(&dev->se_port_lock);
491 		return -ENOSPC;
492 	}
493 again:
494 	/*
495 	 * Allocate the next RELATIVE TARGET PORT IDENTIFIER for this struct se_device
496 	 * Here is the table from spc4r17 section 7.7.3.8.
497 	 *
498 	 *    Table 473 -- RELATIVE TARGET PORT IDENTIFIER field
499 	 *
500 	 * Code      Description
501 	 * 0h        Reserved
502 	 * 1h        Relative port 1, historically known as port A
503 	 * 2h        Relative port 2, historically known as port B
504 	 * 3h to FFFFh    Relative port 3 through 65 535
505 	 */
506 	lun->lun_rtpi = dev->dev_rpti_counter++;
507 	if (!lun->lun_rtpi)
508 		goto again;
509 
510 	list_for_each_entry(tmp, &dev->dev_sep_list, lun_dev_link) {
511 		/*
512 		 * Make sure RELATIVE TARGET PORT IDENTIFIER is unique
513 		 * for 16-bit wrap..
514 		 */
515 		if (lun->lun_rtpi == tmp->lun_rtpi)
516 			goto again;
517 	}
518 	spin_unlock(&dev->se_port_lock);
519 
520 	return 0;
521 }
522 
523 static void se_release_vpd_for_dev(struct se_device *dev)
524 {
525 	struct t10_vpd *vpd, *vpd_tmp;
526 
527 	spin_lock(&dev->t10_wwn.t10_vpd_lock);
528 	list_for_each_entry_safe(vpd, vpd_tmp,
529 			&dev->t10_wwn.t10_vpd_list, vpd_list) {
530 		list_del(&vpd->vpd_list);
531 		kfree(vpd);
532 	}
533 	spin_unlock(&dev->t10_wwn.t10_vpd_lock);
534 }
535 
536 static u32 se_dev_align_max_sectors(u32 max_sectors, u32 block_size)
537 {
538 	u32 aligned_max_sectors;
539 	u32 alignment;
540 	/*
541 	 * Limit max_sectors to a PAGE_SIZE aligned value for modern
542 	 * transport_allocate_data_tasks() operation.
543 	 */
544 	alignment = max(1ul, PAGE_SIZE / block_size);
545 	aligned_max_sectors = rounddown(max_sectors, alignment);
546 
547 	if (max_sectors != aligned_max_sectors)
548 		pr_info("Rounding down aligned max_sectors from %u to %u\n",
549 			max_sectors, aligned_max_sectors);
550 
551 	return aligned_max_sectors;
552 }
553 
554 int core_dev_add_lun(
555 	struct se_portal_group *tpg,
556 	struct se_device *dev,
557 	struct se_lun *lun)
558 {
559 	int rc;
560 
561 	rc = core_tpg_add_lun(tpg, lun, false, dev);
562 	if (rc < 0)
563 		return rc;
564 
565 	pr_debug("%s_TPG[%u]_LUN[%llu] - Activated %s Logical Unit from"
566 		" CORE HBA: %u\n", tpg->se_tpg_tfo->fabric_name,
567 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
568 		tpg->se_tpg_tfo->fabric_name, dev->se_hba->hba_id);
569 	/*
570 	 * Update LUN maps for dynamically added initiators when
571 	 * generate_node_acl is enabled.
572 	 */
573 	if (tpg->se_tpg_tfo->tpg_check_demo_mode(tpg)) {
574 		struct se_node_acl *acl;
575 
576 		mutex_lock(&tpg->acl_node_mutex);
577 		list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
578 			if (acl->dynamic_node_acl &&
579 			    (!tpg->se_tpg_tfo->tpg_check_demo_mode_login_only ||
580 			     !tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg))) {
581 				core_tpg_add_node_to_devs(acl, tpg, lun);
582 			}
583 		}
584 		mutex_unlock(&tpg->acl_node_mutex);
585 	}
586 
587 	return 0;
588 }
589 
590 /*      core_dev_del_lun():
591  *
592  *
593  */
594 void core_dev_del_lun(
595 	struct se_portal_group *tpg,
596 	struct se_lun *lun)
597 {
598 	pr_debug("%s_TPG[%u]_LUN[%llu] - Deactivating %s Logical Unit from"
599 		" device object\n", tpg->se_tpg_tfo->fabric_name,
600 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
601 		tpg->se_tpg_tfo->fabric_name);
602 
603 	core_tpg_remove_lun(tpg, lun);
604 }
605 
606 struct se_lun_acl *core_dev_init_initiator_node_lun_acl(
607 	struct se_portal_group *tpg,
608 	struct se_node_acl *nacl,
609 	u64 mapped_lun,
610 	int *ret)
611 {
612 	struct se_lun_acl *lacl;
613 
614 	if (strlen(nacl->initiatorname) >= TRANSPORT_IQN_LEN) {
615 		pr_err("%s InitiatorName exceeds maximum size.\n",
616 			tpg->se_tpg_tfo->fabric_name);
617 		*ret = -EOVERFLOW;
618 		return NULL;
619 	}
620 	lacl = kzalloc(sizeof(struct se_lun_acl), GFP_KERNEL);
621 	if (!lacl) {
622 		pr_err("Unable to allocate memory for struct se_lun_acl.\n");
623 		*ret = -ENOMEM;
624 		return NULL;
625 	}
626 
627 	lacl->mapped_lun = mapped_lun;
628 	lacl->se_lun_nacl = nacl;
629 
630 	return lacl;
631 }
632 
633 int core_dev_add_initiator_node_lun_acl(
634 	struct se_portal_group *tpg,
635 	struct se_lun_acl *lacl,
636 	struct se_lun *lun,
637 	bool lun_access_ro)
638 {
639 	struct se_node_acl *nacl = lacl->se_lun_nacl;
640 	/*
641 	 * rcu_dereference_raw protected by se_lun->lun_group symlink
642 	 * reference to se_device->dev_group.
643 	 */
644 	struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
645 
646 	if (!nacl)
647 		return -EINVAL;
648 
649 	if (lun->lun_access_ro)
650 		lun_access_ro = true;
651 
652 	lacl->se_lun = lun;
653 
654 	if (core_enable_device_list_for_node(lun, lacl, lacl->mapped_lun,
655 			lun_access_ro, nacl, tpg) < 0)
656 		return -EINVAL;
657 
658 	pr_debug("%s_TPG[%hu]_LUN[%llu->%llu] - Added %s ACL for "
659 		" InitiatorNode: %s\n", tpg->se_tpg_tfo->fabric_name,
660 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun, lacl->mapped_lun,
661 		lun_access_ro ? "RO" : "RW",
662 		nacl->initiatorname);
663 	/*
664 	 * Check to see if there are any existing persistent reservation APTPL
665 	 * pre-registrations that need to be enabled for this LUN ACL..
666 	 */
667 	core_scsi3_check_aptpl_registration(dev, tpg, lun, nacl,
668 					    lacl->mapped_lun);
669 	return 0;
670 }
671 
672 int core_dev_del_initiator_node_lun_acl(
673 	struct se_lun *lun,
674 	struct se_lun_acl *lacl)
675 {
676 	struct se_portal_group *tpg = lun->lun_tpg;
677 	struct se_node_acl *nacl;
678 	struct se_dev_entry *deve;
679 
680 	nacl = lacl->se_lun_nacl;
681 	if (!nacl)
682 		return -EINVAL;
683 
684 	mutex_lock(&nacl->lun_entry_mutex);
685 	deve = target_nacl_find_deve(nacl, lacl->mapped_lun);
686 	if (deve)
687 		core_disable_device_list_for_node(lun, deve, nacl, tpg);
688 	mutex_unlock(&nacl->lun_entry_mutex);
689 
690 	pr_debug("%s_TPG[%hu]_LUN[%llu] - Removed ACL for"
691 		" InitiatorNode: %s Mapped LUN: %llu\n",
692 		tpg->se_tpg_tfo->fabric_name,
693 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
694 		nacl->initiatorname, lacl->mapped_lun);
695 
696 	return 0;
697 }
698 
699 void core_dev_free_initiator_node_lun_acl(
700 	struct se_portal_group *tpg,
701 	struct se_lun_acl *lacl)
702 {
703 	pr_debug("%s_TPG[%hu] - Freeing ACL for %s InitiatorNode: %s"
704 		" Mapped LUN: %llu\n", tpg->se_tpg_tfo->fabric_name,
705 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
706 		tpg->se_tpg_tfo->fabric_name,
707 		lacl->se_lun_nacl->initiatorname, lacl->mapped_lun);
708 
709 	kfree(lacl);
710 }
711 
712 static void scsi_dump_inquiry(struct se_device *dev)
713 {
714 	struct t10_wwn *wwn = &dev->t10_wwn;
715 	int device_type = dev->transport->get_device_type(dev);
716 
717 	/*
718 	 * Print Linux/SCSI style INQUIRY formatting to the kernel ring buffer
719 	 */
720 	pr_debug("  Vendor: %-" __stringify(INQUIRY_VENDOR_LEN) "s\n",
721 		wwn->vendor);
722 	pr_debug("  Model: %-" __stringify(INQUIRY_MODEL_LEN) "s\n",
723 		wwn->model);
724 	pr_debug("  Revision: %-" __stringify(INQUIRY_REVISION_LEN) "s\n",
725 		wwn->revision);
726 	pr_debug("  Type:   %s ", scsi_device_type(device_type));
727 }
728 
729 struct se_device *target_alloc_device(struct se_hba *hba, const char *name)
730 {
731 	struct se_device *dev;
732 	struct se_lun *xcopy_lun;
733 	int i;
734 
735 	dev = hba->backend->ops->alloc_device(hba, name);
736 	if (!dev)
737 		return NULL;
738 
739 	dev->queues = kcalloc(nr_cpu_ids, sizeof(*dev->queues), GFP_KERNEL);
740 	if (!dev->queues) {
741 		dev->transport->free_device(dev);
742 		return NULL;
743 	}
744 
745 	dev->queue_cnt = nr_cpu_ids;
746 	for (i = 0; i < dev->queue_cnt; i++) {
747 		struct se_device_queue *q;
748 
749 		q = &dev->queues[i];
750 		INIT_LIST_HEAD(&q->state_list);
751 		spin_lock_init(&q->lock);
752 
753 		init_llist_head(&q->sq.cmd_list);
754 		INIT_WORK(&q->sq.work, target_queued_submit_work);
755 	}
756 
757 	dev->se_hba = hba;
758 	dev->transport = hba->backend->ops;
759 	dev->transport_flags = dev->transport->transport_flags_default;
760 	dev->prot_length = sizeof(struct t10_pi_tuple);
761 	dev->hba_index = hba->hba_index;
762 
763 	INIT_LIST_HEAD(&dev->dev_sep_list);
764 	INIT_LIST_HEAD(&dev->dev_tmr_list);
765 	INIT_LIST_HEAD(&dev->delayed_cmd_list);
766 	INIT_LIST_HEAD(&dev->qf_cmd_list);
767 	spin_lock_init(&dev->delayed_cmd_lock);
768 	spin_lock_init(&dev->dev_reservation_lock);
769 	spin_lock_init(&dev->se_port_lock);
770 	spin_lock_init(&dev->se_tmr_lock);
771 	spin_lock_init(&dev->qf_cmd_lock);
772 	sema_init(&dev->caw_sem, 1);
773 	INIT_LIST_HEAD(&dev->t10_wwn.t10_vpd_list);
774 	spin_lock_init(&dev->t10_wwn.t10_vpd_lock);
775 	INIT_LIST_HEAD(&dev->t10_pr.registration_list);
776 	INIT_LIST_HEAD(&dev->t10_pr.aptpl_reg_list);
777 	spin_lock_init(&dev->t10_pr.registration_lock);
778 	spin_lock_init(&dev->t10_pr.aptpl_reg_lock);
779 	INIT_LIST_HEAD(&dev->t10_alua.tg_pt_gps_list);
780 	spin_lock_init(&dev->t10_alua.tg_pt_gps_lock);
781 	INIT_LIST_HEAD(&dev->t10_alua.lba_map_list);
782 	spin_lock_init(&dev->t10_alua.lba_map_lock);
783 
784 	INIT_WORK(&dev->delayed_cmd_work, target_do_delayed_work);
785 
786 	dev->t10_wwn.t10_dev = dev;
787 	/*
788 	 * Use OpenFabrics IEEE Company ID: 00 14 05
789 	 */
790 	dev->t10_wwn.company_id = 0x001405;
791 
792 	dev->t10_alua.t10_dev = dev;
793 
794 	dev->dev_attrib.da_dev = dev;
795 	dev->dev_attrib.emulate_model_alias = DA_EMULATE_MODEL_ALIAS;
796 	dev->dev_attrib.emulate_dpo = 1;
797 	dev->dev_attrib.emulate_fua_write = 1;
798 	dev->dev_attrib.emulate_fua_read = 1;
799 	dev->dev_attrib.emulate_write_cache = DA_EMULATE_WRITE_CACHE;
800 	dev->dev_attrib.emulate_ua_intlck_ctrl = TARGET_UA_INTLCK_CTRL_CLEAR;
801 	dev->dev_attrib.emulate_tas = DA_EMULATE_TAS;
802 	dev->dev_attrib.emulate_tpu = DA_EMULATE_TPU;
803 	dev->dev_attrib.emulate_tpws = DA_EMULATE_TPWS;
804 	dev->dev_attrib.emulate_caw = DA_EMULATE_CAW;
805 	dev->dev_attrib.emulate_3pc = DA_EMULATE_3PC;
806 	dev->dev_attrib.emulate_pr = DA_EMULATE_PR;
807 	dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE0_PROT;
808 	dev->dev_attrib.enforce_pr_isids = DA_ENFORCE_PR_ISIDS;
809 	dev->dev_attrib.force_pr_aptpl = DA_FORCE_PR_APTPL;
810 	dev->dev_attrib.is_nonrot = DA_IS_NONROT;
811 	dev->dev_attrib.emulate_rest_reord = DA_EMULATE_REST_REORD;
812 	dev->dev_attrib.max_unmap_lba_count = DA_MAX_UNMAP_LBA_COUNT;
813 	dev->dev_attrib.max_unmap_block_desc_count =
814 		DA_MAX_UNMAP_BLOCK_DESC_COUNT;
815 	dev->dev_attrib.unmap_granularity = DA_UNMAP_GRANULARITY_DEFAULT;
816 	dev->dev_attrib.unmap_granularity_alignment =
817 				DA_UNMAP_GRANULARITY_ALIGNMENT_DEFAULT;
818 	dev->dev_attrib.unmap_zeroes_data =
819 				DA_UNMAP_ZEROES_DATA_DEFAULT;
820 	dev->dev_attrib.max_write_same_len = DA_MAX_WRITE_SAME_LEN;
821 
822 	xcopy_lun = &dev->xcopy_lun;
823 	rcu_assign_pointer(xcopy_lun->lun_se_dev, dev);
824 	init_completion(&xcopy_lun->lun_shutdown_comp);
825 	INIT_LIST_HEAD(&xcopy_lun->lun_deve_list);
826 	INIT_LIST_HEAD(&xcopy_lun->lun_dev_link);
827 	mutex_init(&xcopy_lun->lun_tg_pt_md_mutex);
828 	xcopy_lun->lun_tpg = &xcopy_pt_tpg;
829 
830 	/* Preload the default INQUIRY const values */
831 	strlcpy(dev->t10_wwn.vendor, "LIO-ORG", sizeof(dev->t10_wwn.vendor));
832 	strlcpy(dev->t10_wwn.model, dev->transport->inquiry_prod,
833 		sizeof(dev->t10_wwn.model));
834 	strlcpy(dev->t10_wwn.revision, dev->transport->inquiry_rev,
835 		sizeof(dev->t10_wwn.revision));
836 
837 	return dev;
838 }
839 
840 /*
841  * Check if the underlying struct block_device supports discard and if yes
842  * configure the UNMAP parameters.
843  */
844 bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib,
845 				       struct block_device *bdev)
846 {
847 	int block_size = bdev_logical_block_size(bdev);
848 
849 	if (!bdev_max_discard_sectors(bdev))
850 		return false;
851 
852 	attrib->max_unmap_lba_count =
853 		bdev_max_discard_sectors(bdev) >> (ilog2(block_size) - 9);
854 	/*
855 	 * Currently hardcoded to 1 in Linux/SCSI code..
856 	 */
857 	attrib->max_unmap_block_desc_count = 1;
858 	attrib->unmap_granularity = bdev_discard_granularity(bdev) / block_size;
859 	attrib->unmap_granularity_alignment =
860 		bdev_discard_alignment(bdev) / block_size;
861 	return true;
862 }
863 EXPORT_SYMBOL(target_configure_unmap_from_queue);
864 
865 /*
866  * Convert from blocksize advertised to the initiator to the 512 byte
867  * units unconditionally used by the Linux block layer.
868  */
869 sector_t target_to_linux_sector(struct se_device *dev, sector_t lb)
870 {
871 	switch (dev->dev_attrib.block_size) {
872 	case 4096:
873 		return lb << 3;
874 	case 2048:
875 		return lb << 2;
876 	case 1024:
877 		return lb << 1;
878 	default:
879 		return lb;
880 	}
881 }
882 EXPORT_SYMBOL(target_to_linux_sector);
883 
884 struct devices_idr_iter {
885 	struct config_item *prev_item;
886 	int (*fn)(struct se_device *dev, void *data);
887 	void *data;
888 };
889 
890 static int target_devices_idr_iter(int id, void *p, void *data)
891 	 __must_hold(&device_mutex)
892 {
893 	struct devices_idr_iter *iter = data;
894 	struct se_device *dev = p;
895 	int ret;
896 
897 	config_item_put(iter->prev_item);
898 	iter->prev_item = NULL;
899 
900 	/*
901 	 * We add the device early to the idr, so it can be used
902 	 * by backend modules during configuration. We do not want
903 	 * to allow other callers to access partially setup devices,
904 	 * so we skip them here.
905 	 */
906 	if (!target_dev_configured(dev))
907 		return 0;
908 
909 	iter->prev_item = config_item_get_unless_zero(&dev->dev_group.cg_item);
910 	if (!iter->prev_item)
911 		return 0;
912 	mutex_unlock(&device_mutex);
913 
914 	ret = iter->fn(dev, iter->data);
915 
916 	mutex_lock(&device_mutex);
917 	return ret;
918 }
919 
920 /**
921  * target_for_each_device - iterate over configured devices
922  * @fn: iterator function
923  * @data: pointer to data that will be passed to fn
924  *
925  * fn must return 0 to continue looping over devices. non-zero will break
926  * from the loop and return that value to the caller.
927  */
928 int target_for_each_device(int (*fn)(struct se_device *dev, void *data),
929 			   void *data)
930 {
931 	struct devices_idr_iter iter = { .fn = fn, .data = data };
932 	int ret;
933 
934 	mutex_lock(&device_mutex);
935 	ret = idr_for_each(&devices_idr, target_devices_idr_iter, &iter);
936 	mutex_unlock(&device_mutex);
937 	config_item_put(iter.prev_item);
938 	return ret;
939 }
940 
941 int target_configure_device(struct se_device *dev)
942 {
943 	struct se_hba *hba = dev->se_hba;
944 	int ret, id;
945 
946 	if (target_dev_configured(dev)) {
947 		pr_err("se_dev->se_dev_ptr already set for storage"
948 				" object\n");
949 		return -EEXIST;
950 	}
951 
952 	/*
953 	 * Add early so modules like tcmu can use during its
954 	 * configuration.
955 	 */
956 	mutex_lock(&device_mutex);
957 	/*
958 	 * Use cyclic to try and avoid collisions with devices
959 	 * that were recently removed.
960 	 */
961 	id = idr_alloc_cyclic(&devices_idr, dev, 0, INT_MAX, GFP_KERNEL);
962 	mutex_unlock(&device_mutex);
963 	if (id < 0) {
964 		ret = -ENOMEM;
965 		goto out;
966 	}
967 	dev->dev_index = id;
968 
969 	ret = dev->transport->configure_device(dev);
970 	if (ret)
971 		goto out_free_index;
972 
973 	if (dev->transport->configure_unmap &&
974 	    dev->transport->configure_unmap(dev)) {
975 		pr_debug("Discard support available, but disabled by default.\n");
976 	}
977 
978 	/*
979 	 * XXX: there is not much point to have two different values here..
980 	 */
981 	dev->dev_attrib.block_size = dev->dev_attrib.hw_block_size;
982 	dev->dev_attrib.queue_depth = dev->dev_attrib.hw_queue_depth;
983 
984 	/*
985 	 * Align max_hw_sectors down to PAGE_SIZE I/O transfers
986 	 */
987 	dev->dev_attrib.hw_max_sectors =
988 		se_dev_align_max_sectors(dev->dev_attrib.hw_max_sectors,
989 					 dev->dev_attrib.hw_block_size);
990 	dev->dev_attrib.optimal_sectors = dev->dev_attrib.hw_max_sectors;
991 
992 	dev->creation_time = get_jiffies_64();
993 
994 	ret = core_setup_alua(dev);
995 	if (ret)
996 		goto out_destroy_device;
997 
998 	/*
999 	 * Setup work_queue for QUEUE_FULL
1000 	 */
1001 	INIT_WORK(&dev->qf_work_queue, target_qf_do_work);
1002 
1003 	scsi_dump_inquiry(dev);
1004 
1005 	spin_lock(&hba->device_lock);
1006 	hba->dev_count++;
1007 	spin_unlock(&hba->device_lock);
1008 
1009 	dev->dev_flags |= DF_CONFIGURED;
1010 
1011 	return 0;
1012 
1013 out_destroy_device:
1014 	dev->transport->destroy_device(dev);
1015 out_free_index:
1016 	mutex_lock(&device_mutex);
1017 	idr_remove(&devices_idr, dev->dev_index);
1018 	mutex_unlock(&device_mutex);
1019 out:
1020 	se_release_vpd_for_dev(dev);
1021 	return ret;
1022 }
1023 
1024 void target_free_device(struct se_device *dev)
1025 {
1026 	struct se_hba *hba = dev->se_hba;
1027 
1028 	WARN_ON(!list_empty(&dev->dev_sep_list));
1029 
1030 	if (target_dev_configured(dev)) {
1031 		dev->transport->destroy_device(dev);
1032 
1033 		mutex_lock(&device_mutex);
1034 		idr_remove(&devices_idr, dev->dev_index);
1035 		mutex_unlock(&device_mutex);
1036 
1037 		spin_lock(&hba->device_lock);
1038 		hba->dev_count--;
1039 		spin_unlock(&hba->device_lock);
1040 	}
1041 
1042 	core_alua_free_lu_gp_mem(dev);
1043 	core_alua_set_lba_map(dev, NULL, 0, 0);
1044 	core_scsi3_free_all_registrations(dev);
1045 	se_release_vpd_for_dev(dev);
1046 
1047 	if (dev->transport->free_prot)
1048 		dev->transport->free_prot(dev);
1049 
1050 	kfree(dev->queues);
1051 	dev->transport->free_device(dev);
1052 }
1053 
1054 int core_dev_setup_virtual_lun0(void)
1055 {
1056 	struct se_hba *hba;
1057 	struct se_device *dev;
1058 	char buf[] = "rd_pages=8,rd_nullio=1,rd_dummy=1";
1059 	int ret;
1060 
1061 	hba = core_alloc_hba("rd_mcp", 0, HBA_FLAGS_INTERNAL_USE);
1062 	if (IS_ERR(hba))
1063 		return PTR_ERR(hba);
1064 
1065 	dev = target_alloc_device(hba, "virt_lun0");
1066 	if (!dev) {
1067 		ret = -ENOMEM;
1068 		goto out_free_hba;
1069 	}
1070 
1071 	hba->backend->ops->set_configfs_dev_params(dev, buf, sizeof(buf));
1072 
1073 	ret = target_configure_device(dev);
1074 	if (ret)
1075 		goto out_free_se_dev;
1076 
1077 	lun0_hba = hba;
1078 	g_lun0_dev = dev;
1079 	return 0;
1080 
1081 out_free_se_dev:
1082 	target_free_device(dev);
1083 out_free_hba:
1084 	core_delete_hba(hba);
1085 	return ret;
1086 }
1087 
1088 
1089 void core_dev_release_virtual_lun0(void)
1090 {
1091 	struct se_hba *hba = lun0_hba;
1092 
1093 	if (!hba)
1094 		return;
1095 
1096 	if (g_lun0_dev)
1097 		target_free_device(g_lun0_dev);
1098 	core_delete_hba(hba);
1099 }
1100 
1101 /*
1102  * Common CDB parsing for kernel and user passthrough.
1103  */
1104 sense_reason_t
1105 passthrough_parse_cdb(struct se_cmd *cmd,
1106 	sense_reason_t (*exec_cmd)(struct se_cmd *cmd))
1107 {
1108 	unsigned char *cdb = cmd->t_task_cdb;
1109 	struct se_device *dev = cmd->se_dev;
1110 	unsigned int size;
1111 
1112 	/*
1113 	 * For REPORT LUNS we always need to emulate the response, for everything
1114 	 * else, pass it up.
1115 	 */
1116 	if (cdb[0] == REPORT_LUNS) {
1117 		cmd->execute_cmd = spc_emulate_report_luns;
1118 		return TCM_NO_SENSE;
1119 	}
1120 
1121 	/*
1122 	 * With emulate_pr disabled, all reservation requests should fail,
1123 	 * regardless of whether or not TRANSPORT_FLAG_PASSTHROUGH_PGR is set.
1124 	 */
1125 	if (!dev->dev_attrib.emulate_pr &&
1126 	    ((cdb[0] == PERSISTENT_RESERVE_IN) ||
1127 	     (cdb[0] == PERSISTENT_RESERVE_OUT) ||
1128 	     (cdb[0] == RELEASE || cdb[0] == RELEASE_10) ||
1129 	     (cdb[0] == RESERVE || cdb[0] == RESERVE_10))) {
1130 		return TCM_UNSUPPORTED_SCSI_OPCODE;
1131 	}
1132 
1133 	/*
1134 	 * For PERSISTENT RESERVE IN/OUT, RELEASE, and RESERVE we need to
1135 	 * emulate the response, since tcmu does not have the information
1136 	 * required to process these commands.
1137 	 */
1138 	if (!(dev->transport_flags &
1139 	      TRANSPORT_FLAG_PASSTHROUGH_PGR)) {
1140 		if (cdb[0] == PERSISTENT_RESERVE_IN) {
1141 			cmd->execute_cmd = target_scsi3_emulate_pr_in;
1142 			size = get_unaligned_be16(&cdb[7]);
1143 			return target_cmd_size_check(cmd, size);
1144 		}
1145 		if (cdb[0] == PERSISTENT_RESERVE_OUT) {
1146 			cmd->execute_cmd = target_scsi3_emulate_pr_out;
1147 			size = get_unaligned_be32(&cdb[5]);
1148 			return target_cmd_size_check(cmd, size);
1149 		}
1150 
1151 		if (cdb[0] == RELEASE || cdb[0] == RELEASE_10) {
1152 			cmd->execute_cmd = target_scsi2_reservation_release;
1153 			if (cdb[0] == RELEASE_10)
1154 				size = get_unaligned_be16(&cdb[7]);
1155 			else
1156 				size = cmd->data_length;
1157 			return target_cmd_size_check(cmd, size);
1158 		}
1159 		if (cdb[0] == RESERVE || cdb[0] == RESERVE_10) {
1160 			cmd->execute_cmd = target_scsi2_reservation_reserve;
1161 			if (cdb[0] == RESERVE_10)
1162 				size = get_unaligned_be16(&cdb[7]);
1163 			else
1164 				size = cmd->data_length;
1165 			return target_cmd_size_check(cmd, size);
1166 		}
1167 	}
1168 
1169 	/* Set DATA_CDB flag for ops that should have it */
1170 	switch (cdb[0]) {
1171 	case READ_6:
1172 	case READ_10:
1173 	case READ_12:
1174 	case READ_16:
1175 	case WRITE_6:
1176 	case WRITE_10:
1177 	case WRITE_12:
1178 	case WRITE_16:
1179 	case WRITE_VERIFY:
1180 	case WRITE_VERIFY_12:
1181 	case WRITE_VERIFY_16:
1182 	case COMPARE_AND_WRITE:
1183 	case XDWRITEREAD_10:
1184 		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
1185 		break;
1186 	case VARIABLE_LENGTH_CMD:
1187 		switch (get_unaligned_be16(&cdb[8])) {
1188 		case READ_32:
1189 		case WRITE_32:
1190 		case WRITE_VERIFY_32:
1191 		case XDWRITEREAD_32:
1192 			cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
1193 			break;
1194 		}
1195 	}
1196 
1197 	cmd->execute_cmd = exec_cmd;
1198 
1199 	return TCM_NO_SENSE;
1200 }
1201 EXPORT_SYMBOL(passthrough_parse_cdb);
1202