xref: /linux/drivers/target/target_core_device.c (revision 5f14596e55de458987ee38043019b3d5cd636af1)
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, u64 unpacked_lun)
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, unpacked_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 		se_lun = rcu_dereference(deve->se_lun);
69 
70 		if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {
71 			se_lun = NULL;
72 			goto out_unlock;
73 		}
74 
75 		se_cmd->se_lun = se_lun;
76 		se_cmd->pr_res_key = deve->pr_res_key;
77 		se_cmd->orig_fe_lun = unpacked_lun;
78 		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
79 		se_cmd->lun_ref_active = true;
80 
81 		if ((se_cmd->data_direction == DMA_TO_DEVICE) &&
82 		    deve->lun_access_ro) {
83 			pr_err("TARGET_CORE[%s]: Detected WRITE_PROTECTED LUN"
84 				" Access for 0x%08llx\n",
85 				se_cmd->se_tfo->fabric_name,
86 				unpacked_lun);
87 			rcu_read_unlock();
88 			ret = TCM_WRITE_PROTECTED;
89 			goto ref_dev;
90 		}
91 	}
92 out_unlock:
93 	rcu_read_unlock();
94 
95 	if (!se_lun) {
96 		/*
97 		 * Use the se_portal_group->tpg_virt_lun0 to allow for
98 		 * REPORT_LUNS, et al to be returned when no active
99 		 * MappedLUN=0 exists for this Initiator Port.
100 		 */
101 		if (unpacked_lun != 0) {
102 			pr_err("TARGET_CORE[%s]: Detected NON_EXISTENT_LUN"
103 				" Access for 0x%08llx from %s\n",
104 				se_cmd->se_tfo->fabric_name,
105 				unpacked_lun,
106 				nacl->initiatorname);
107 			return TCM_NON_EXISTENT_LUN;
108 		}
109 
110 		se_lun = se_sess->se_tpg->tpg_virt_lun0;
111 		se_cmd->se_lun = se_sess->se_tpg->tpg_virt_lun0;
112 		se_cmd->orig_fe_lun = 0;
113 		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
114 
115 		percpu_ref_get(&se_lun->lun_ref);
116 		se_cmd->lun_ref_active = true;
117 
118 		/*
119 		 * Force WRITE PROTECT for virtual LUN 0
120 		 */
121 		if ((se_cmd->data_direction != DMA_FROM_DEVICE) &&
122 		    (se_cmd->data_direction != DMA_NONE)) {
123 			ret = TCM_WRITE_PROTECTED;
124 			goto ref_dev;
125 		}
126 	}
127 	/*
128 	 * RCU reference protected by percpu se_lun->lun_ref taken above that
129 	 * must drop to zero (including initial reference) before this se_lun
130 	 * pointer can be kfree_rcu() by the final se_lun->lun_group put via
131 	 * target_core_fabric_configfs.c:target_fabric_port_release
132 	 */
133 ref_dev:
134 	se_cmd->se_dev = rcu_dereference_raw(se_lun->lun_se_dev);
135 	atomic_long_inc(&se_cmd->se_dev->num_cmds);
136 
137 	if (se_cmd->data_direction == DMA_TO_DEVICE)
138 		atomic_long_add(se_cmd->data_length,
139 				&se_cmd->se_dev->write_bytes);
140 	else if (se_cmd->data_direction == DMA_FROM_DEVICE)
141 		atomic_long_add(se_cmd->data_length,
142 				&se_cmd->se_dev->read_bytes);
143 
144 	return ret;
145 }
146 EXPORT_SYMBOL(transport_lookup_cmd_lun);
147 
148 int transport_lookup_tmr_lun(struct se_cmd *se_cmd, u64 unpacked_lun)
149 {
150 	struct se_dev_entry *deve;
151 	struct se_lun *se_lun = NULL;
152 	struct se_session *se_sess = se_cmd->se_sess;
153 	struct se_node_acl *nacl = se_sess->se_node_acl;
154 	struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
155 	unsigned long flags;
156 
157 	rcu_read_lock();
158 	deve = target_nacl_find_deve(nacl, unpacked_lun);
159 	if (deve) {
160 		se_lun = rcu_dereference(deve->se_lun);
161 
162 		if (!percpu_ref_tryget_live(&se_lun->lun_ref)) {
163 			se_lun = NULL;
164 			goto out_unlock;
165 		}
166 
167 		se_cmd->se_lun = se_lun;
168 		se_cmd->pr_res_key = deve->pr_res_key;
169 		se_cmd->orig_fe_lun = unpacked_lun;
170 		se_cmd->se_cmd_flags |= SCF_SE_LUN_CMD;
171 		se_cmd->lun_ref_active = true;
172 	}
173 out_unlock:
174 	rcu_read_unlock();
175 
176 	if (!se_lun) {
177 		pr_debug("TARGET_CORE[%s]: Detected NON_EXISTENT_LUN"
178 			" Access for 0x%08llx for %s\n",
179 			se_cmd->se_tfo->fabric_name,
180 			unpacked_lun,
181 			nacl->initiatorname);
182 		return -ENODEV;
183 	}
184 	se_cmd->se_dev = rcu_dereference_raw(se_lun->lun_se_dev);
185 	se_tmr->tmr_dev = rcu_dereference_raw(se_lun->lun_se_dev);
186 
187 	spin_lock_irqsave(&se_tmr->tmr_dev->se_tmr_lock, flags);
188 	list_add_tail(&se_tmr->tmr_list, &se_tmr->tmr_dev->dev_tmr_list);
189 	spin_unlock_irqrestore(&se_tmr->tmr_dev->se_tmr_lock, flags);
190 
191 	return 0;
192 }
193 EXPORT_SYMBOL(transport_lookup_tmr_lun);
194 
195 bool target_lun_is_rdonly(struct se_cmd *cmd)
196 {
197 	struct se_session *se_sess = cmd->se_sess;
198 	struct se_dev_entry *deve;
199 	bool ret;
200 
201 	rcu_read_lock();
202 	deve = target_nacl_find_deve(se_sess->se_node_acl, cmd->orig_fe_lun);
203 	ret = deve && deve->lun_access_ro;
204 	rcu_read_unlock();
205 
206 	return ret;
207 }
208 EXPORT_SYMBOL(target_lun_is_rdonly);
209 
210 /*
211  * This function is called from core_scsi3_emulate_pro_register_and_move()
212  * and core_scsi3_decode_spec_i_port(), and will increment &deve->pr_kref
213  * when a matching rtpi is found.
214  */
215 struct se_dev_entry *core_get_se_deve_from_rtpi(
216 	struct se_node_acl *nacl,
217 	u16 rtpi)
218 {
219 	struct se_dev_entry *deve;
220 	struct se_lun *lun;
221 	struct se_portal_group *tpg = nacl->se_tpg;
222 
223 	rcu_read_lock();
224 	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
225 		lun = rcu_dereference(deve->se_lun);
226 		if (!lun) {
227 			pr_err("%s device entries device pointer is"
228 				" NULL, but Initiator has access.\n",
229 				tpg->se_tpg_tfo->fabric_name);
230 			continue;
231 		}
232 		if (lun->lun_rtpi != rtpi)
233 			continue;
234 
235 		kref_get(&deve->pr_kref);
236 		rcu_read_unlock();
237 
238 		return deve;
239 	}
240 	rcu_read_unlock();
241 
242 	return NULL;
243 }
244 
245 void core_free_device_list_for_node(
246 	struct se_node_acl *nacl,
247 	struct se_portal_group *tpg)
248 {
249 	struct se_dev_entry *deve;
250 
251 	mutex_lock(&nacl->lun_entry_mutex);
252 	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
253 		struct se_lun *lun = rcu_dereference_check(deve->se_lun,
254 					lockdep_is_held(&nacl->lun_entry_mutex));
255 		core_disable_device_list_for_node(lun, deve, nacl, tpg);
256 	}
257 	mutex_unlock(&nacl->lun_entry_mutex);
258 }
259 
260 void core_update_device_list_access(
261 	u64 mapped_lun,
262 	bool lun_access_ro,
263 	struct se_node_acl *nacl)
264 {
265 	struct se_dev_entry *deve;
266 
267 	mutex_lock(&nacl->lun_entry_mutex);
268 	deve = target_nacl_find_deve(nacl, mapped_lun);
269 	if (deve)
270 		deve->lun_access_ro = lun_access_ro;
271 	mutex_unlock(&nacl->lun_entry_mutex);
272 }
273 
274 /*
275  * Called with rcu_read_lock or nacl->device_list_lock held.
276  */
277 struct se_dev_entry *target_nacl_find_deve(struct se_node_acl *nacl, u64 mapped_lun)
278 {
279 	struct se_dev_entry *deve;
280 
281 	hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link)
282 		if (deve->mapped_lun == mapped_lun)
283 			return deve;
284 
285 	return NULL;
286 }
287 EXPORT_SYMBOL(target_nacl_find_deve);
288 
289 void target_pr_kref_release(struct kref *kref)
290 {
291 	struct se_dev_entry *deve = container_of(kref, struct se_dev_entry,
292 						 pr_kref);
293 	complete(&deve->pr_comp);
294 }
295 
296 static void
297 target_luns_data_has_changed(struct se_node_acl *nacl, struct se_dev_entry *new,
298 			     bool skip_new)
299 {
300 	struct se_dev_entry *tmp;
301 
302 	rcu_read_lock();
303 	hlist_for_each_entry_rcu(tmp, &nacl->lun_entry_hlist, link) {
304 		if (skip_new && tmp == new)
305 			continue;
306 		core_scsi3_ua_allocate(tmp, 0x3F,
307 				       ASCQ_3FH_REPORTED_LUNS_DATA_HAS_CHANGED);
308 	}
309 	rcu_read_unlock();
310 }
311 
312 int core_enable_device_list_for_node(
313 	struct se_lun *lun,
314 	struct se_lun_acl *lun_acl,
315 	u64 mapped_lun,
316 	bool lun_access_ro,
317 	struct se_node_acl *nacl,
318 	struct se_portal_group *tpg)
319 {
320 	struct se_dev_entry *orig, *new;
321 
322 	new = kzalloc(sizeof(*new), GFP_KERNEL);
323 	if (!new) {
324 		pr_err("Unable to allocate se_dev_entry memory\n");
325 		return -ENOMEM;
326 	}
327 
328 	spin_lock_init(&new->ua_lock);
329 	INIT_LIST_HEAD(&new->ua_list);
330 	INIT_LIST_HEAD(&new->lun_link);
331 
332 	new->mapped_lun = mapped_lun;
333 	kref_init(&new->pr_kref);
334 	init_completion(&new->pr_comp);
335 
336 	new->lun_access_ro = lun_access_ro;
337 	new->creation_time = get_jiffies_64();
338 	new->attach_count++;
339 
340 	mutex_lock(&nacl->lun_entry_mutex);
341 	orig = target_nacl_find_deve(nacl, mapped_lun);
342 	if (orig && orig->se_lun) {
343 		struct se_lun *orig_lun = rcu_dereference_check(orig->se_lun,
344 					lockdep_is_held(&nacl->lun_entry_mutex));
345 
346 		if (orig_lun != lun) {
347 			pr_err("Existing orig->se_lun doesn't match new lun"
348 			       " for dynamic -> explicit NodeACL conversion:"
349 				" %s\n", nacl->initiatorname);
350 			mutex_unlock(&nacl->lun_entry_mutex);
351 			kfree(new);
352 			return -EINVAL;
353 		}
354 		if (orig->se_lun_acl != NULL) {
355 			pr_warn_ratelimited("Detected existing explicit"
356 				" se_lun_acl->se_lun_group reference for %s"
357 				" mapped_lun: %llu, failing\n",
358 				 nacl->initiatorname, mapped_lun);
359 			mutex_unlock(&nacl->lun_entry_mutex);
360 			kfree(new);
361 			return -EINVAL;
362 		}
363 
364 		rcu_assign_pointer(new->se_lun, lun);
365 		rcu_assign_pointer(new->se_lun_acl, lun_acl);
366 		hlist_del_rcu(&orig->link);
367 		hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);
368 		mutex_unlock(&nacl->lun_entry_mutex);
369 
370 		spin_lock(&lun->lun_deve_lock);
371 		list_del(&orig->lun_link);
372 		list_add_tail(&new->lun_link, &lun->lun_deve_list);
373 		spin_unlock(&lun->lun_deve_lock);
374 
375 		kref_put(&orig->pr_kref, target_pr_kref_release);
376 		wait_for_completion(&orig->pr_comp);
377 
378 		target_luns_data_has_changed(nacl, new, true);
379 		kfree_rcu(orig, rcu_head);
380 		return 0;
381 	}
382 
383 	rcu_assign_pointer(new->se_lun, lun);
384 	rcu_assign_pointer(new->se_lun_acl, lun_acl);
385 	hlist_add_head_rcu(&new->link, &nacl->lun_entry_hlist);
386 	mutex_unlock(&nacl->lun_entry_mutex);
387 
388 	spin_lock(&lun->lun_deve_lock);
389 	list_add_tail(&new->lun_link, &lun->lun_deve_list);
390 	spin_unlock(&lun->lun_deve_lock);
391 
392 	target_luns_data_has_changed(nacl, new, true);
393 	return 0;
394 }
395 
396 void core_disable_device_list_for_node(
397 	struct se_lun *lun,
398 	struct se_dev_entry *orig,
399 	struct se_node_acl *nacl,
400 	struct se_portal_group *tpg)
401 {
402 	/*
403 	 * rcu_dereference_raw protected by se_lun->lun_group symlink
404 	 * reference to se_device->dev_group.
405 	 */
406 	struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
407 
408 	lockdep_assert_held(&nacl->lun_entry_mutex);
409 
410 	/*
411 	 * If the MappedLUN entry is being disabled, the entry in
412 	 * lun->lun_deve_list must be removed now before clearing the
413 	 * struct se_dev_entry pointers below as logic in
414 	 * core_alua_do_transition_tg_pt() depends on these being present.
415 	 *
416 	 * deve->se_lun_acl will be NULL for demo-mode created LUNs
417 	 * that have not been explicitly converted to MappedLUNs ->
418 	 * struct se_lun_acl, but we remove deve->lun_link from
419 	 * lun->lun_deve_list. This also means that active UAs and
420 	 * NodeACL context specific PR metadata for demo-mode
421 	 * MappedLUN *deve will be released below..
422 	 */
423 	spin_lock(&lun->lun_deve_lock);
424 	list_del(&orig->lun_link);
425 	spin_unlock(&lun->lun_deve_lock);
426 	/*
427 	 * Disable struct se_dev_entry LUN ACL mapping
428 	 */
429 	core_scsi3_ua_release_all(orig);
430 
431 	hlist_del_rcu(&orig->link);
432 	clear_bit(DEF_PR_REG_ACTIVE, &orig->deve_flags);
433 	orig->lun_access_ro = false;
434 	orig->creation_time = 0;
435 	orig->attach_count--;
436 	/*
437 	 * Before firing off RCU callback, wait for any in process SPEC_I_PT=1
438 	 * or REGISTER_AND_MOVE PR operation to complete.
439 	 */
440 	kref_put(&orig->pr_kref, target_pr_kref_release);
441 	wait_for_completion(&orig->pr_comp);
442 
443 	rcu_assign_pointer(orig->se_lun, NULL);
444 	rcu_assign_pointer(orig->se_lun_acl, NULL);
445 
446 	kfree_rcu(orig, rcu_head);
447 
448 	core_scsi3_free_pr_reg_from_nacl(dev, nacl);
449 	target_luns_data_has_changed(nacl, NULL, false);
450 }
451 
452 /*      core_clear_lun_from_tpg():
453  *
454  *
455  */
456 void core_clear_lun_from_tpg(struct se_lun *lun, struct se_portal_group *tpg)
457 {
458 	struct se_node_acl *nacl;
459 	struct se_dev_entry *deve;
460 
461 	mutex_lock(&tpg->acl_node_mutex);
462 	list_for_each_entry(nacl, &tpg->acl_node_list, acl_list) {
463 
464 		mutex_lock(&nacl->lun_entry_mutex);
465 		hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) {
466 			struct se_lun *tmp_lun = rcu_dereference_check(deve->se_lun,
467 					lockdep_is_held(&nacl->lun_entry_mutex));
468 
469 			if (lun != tmp_lun)
470 				continue;
471 
472 			core_disable_device_list_for_node(lun, deve, nacl, tpg);
473 		}
474 		mutex_unlock(&nacl->lun_entry_mutex);
475 	}
476 	mutex_unlock(&tpg->acl_node_mutex);
477 }
478 
479 int core_alloc_rtpi(struct se_lun *lun, struct se_device *dev)
480 {
481 	struct se_lun *tmp;
482 
483 	spin_lock(&dev->se_port_lock);
484 	if (dev->export_count == 0x0000ffff) {
485 		pr_warn("Reached dev->dev_port_count =="
486 				" 0x0000ffff\n");
487 		spin_unlock(&dev->se_port_lock);
488 		return -ENOSPC;
489 	}
490 again:
491 	/*
492 	 * Allocate the next RELATIVE TARGET PORT IDENTIFIER for this struct se_device
493 	 * Here is the table from spc4r17 section 7.7.3.8.
494 	 *
495 	 *    Table 473 -- RELATIVE TARGET PORT IDENTIFIER field
496 	 *
497 	 * Code      Description
498 	 * 0h        Reserved
499 	 * 1h        Relative port 1, historically known as port A
500 	 * 2h        Relative port 2, historically known as port B
501 	 * 3h to FFFFh    Relative port 3 through 65 535
502 	 */
503 	lun->lun_rtpi = dev->dev_rpti_counter++;
504 	if (!lun->lun_rtpi)
505 		goto again;
506 
507 	list_for_each_entry(tmp, &dev->dev_sep_list, lun_dev_link) {
508 		/*
509 		 * Make sure RELATIVE TARGET PORT IDENTIFIER is unique
510 		 * for 16-bit wrap..
511 		 */
512 		if (lun->lun_rtpi == tmp->lun_rtpi)
513 			goto again;
514 	}
515 	spin_unlock(&dev->se_port_lock);
516 
517 	return 0;
518 }
519 
520 static void se_release_vpd_for_dev(struct se_device *dev)
521 {
522 	struct t10_vpd *vpd, *vpd_tmp;
523 
524 	spin_lock(&dev->t10_wwn.t10_vpd_lock);
525 	list_for_each_entry_safe(vpd, vpd_tmp,
526 			&dev->t10_wwn.t10_vpd_list, vpd_list) {
527 		list_del(&vpd->vpd_list);
528 		kfree(vpd);
529 	}
530 	spin_unlock(&dev->t10_wwn.t10_vpd_lock);
531 }
532 
533 static u32 se_dev_align_max_sectors(u32 max_sectors, u32 block_size)
534 {
535 	u32 aligned_max_sectors;
536 	u32 alignment;
537 	/*
538 	 * Limit max_sectors to a PAGE_SIZE aligned value for modern
539 	 * transport_allocate_data_tasks() operation.
540 	 */
541 	alignment = max(1ul, PAGE_SIZE / block_size);
542 	aligned_max_sectors = rounddown(max_sectors, alignment);
543 
544 	if (max_sectors != aligned_max_sectors)
545 		pr_info("Rounding down aligned max_sectors from %u to %u\n",
546 			max_sectors, aligned_max_sectors);
547 
548 	return aligned_max_sectors;
549 }
550 
551 int core_dev_add_lun(
552 	struct se_portal_group *tpg,
553 	struct se_device *dev,
554 	struct se_lun *lun)
555 {
556 	int rc;
557 
558 	rc = core_tpg_add_lun(tpg, lun, false, dev);
559 	if (rc < 0)
560 		return rc;
561 
562 	pr_debug("%s_TPG[%u]_LUN[%llu] - Activated %s Logical Unit from"
563 		" CORE HBA: %u\n", tpg->se_tpg_tfo->fabric_name,
564 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
565 		tpg->se_tpg_tfo->fabric_name, dev->se_hba->hba_id);
566 	/*
567 	 * Update LUN maps for dynamically added initiators when
568 	 * generate_node_acl is enabled.
569 	 */
570 	if (tpg->se_tpg_tfo->tpg_check_demo_mode(tpg)) {
571 		struct se_node_acl *acl;
572 
573 		mutex_lock(&tpg->acl_node_mutex);
574 		list_for_each_entry(acl, &tpg->acl_node_list, acl_list) {
575 			if (acl->dynamic_node_acl &&
576 			    (!tpg->se_tpg_tfo->tpg_check_demo_mode_login_only ||
577 			     !tpg->se_tpg_tfo->tpg_check_demo_mode_login_only(tpg))) {
578 				core_tpg_add_node_to_devs(acl, tpg, lun);
579 			}
580 		}
581 		mutex_unlock(&tpg->acl_node_mutex);
582 	}
583 
584 	return 0;
585 }
586 
587 /*      core_dev_del_lun():
588  *
589  *
590  */
591 void core_dev_del_lun(
592 	struct se_portal_group *tpg,
593 	struct se_lun *lun)
594 {
595 	pr_debug("%s_TPG[%u]_LUN[%llu] - Deactivating %s Logical Unit from"
596 		" device object\n", tpg->se_tpg_tfo->fabric_name,
597 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
598 		tpg->se_tpg_tfo->fabric_name);
599 
600 	core_tpg_remove_lun(tpg, lun);
601 }
602 
603 struct se_lun_acl *core_dev_init_initiator_node_lun_acl(
604 	struct se_portal_group *tpg,
605 	struct se_node_acl *nacl,
606 	u64 mapped_lun,
607 	int *ret)
608 {
609 	struct se_lun_acl *lacl;
610 
611 	if (strlen(nacl->initiatorname) >= TRANSPORT_IQN_LEN) {
612 		pr_err("%s InitiatorName exceeds maximum size.\n",
613 			tpg->se_tpg_tfo->fabric_name);
614 		*ret = -EOVERFLOW;
615 		return NULL;
616 	}
617 	lacl = kzalloc(sizeof(struct se_lun_acl), GFP_KERNEL);
618 	if (!lacl) {
619 		pr_err("Unable to allocate memory for struct se_lun_acl.\n");
620 		*ret = -ENOMEM;
621 		return NULL;
622 	}
623 
624 	lacl->mapped_lun = mapped_lun;
625 	lacl->se_lun_nacl = nacl;
626 
627 	return lacl;
628 }
629 
630 int core_dev_add_initiator_node_lun_acl(
631 	struct se_portal_group *tpg,
632 	struct se_lun_acl *lacl,
633 	struct se_lun *lun,
634 	bool lun_access_ro)
635 {
636 	struct se_node_acl *nacl = lacl->se_lun_nacl;
637 	/*
638 	 * rcu_dereference_raw protected by se_lun->lun_group symlink
639 	 * reference to se_device->dev_group.
640 	 */
641 	struct se_device *dev = rcu_dereference_raw(lun->lun_se_dev);
642 
643 	if (!nacl)
644 		return -EINVAL;
645 
646 	if (lun->lun_access_ro)
647 		lun_access_ro = true;
648 
649 	lacl->se_lun = lun;
650 
651 	if (core_enable_device_list_for_node(lun, lacl, lacl->mapped_lun,
652 			lun_access_ro, nacl, tpg) < 0)
653 		return -EINVAL;
654 
655 	pr_debug("%s_TPG[%hu]_LUN[%llu->%llu] - Added %s ACL for "
656 		" InitiatorNode: %s\n", tpg->se_tpg_tfo->fabric_name,
657 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun, lacl->mapped_lun,
658 		lun_access_ro ? "RO" : "RW",
659 		nacl->initiatorname);
660 	/*
661 	 * Check to see if there are any existing persistent reservation APTPL
662 	 * pre-registrations that need to be enabled for this LUN ACL..
663 	 */
664 	core_scsi3_check_aptpl_registration(dev, tpg, lun, nacl,
665 					    lacl->mapped_lun);
666 	return 0;
667 }
668 
669 int core_dev_del_initiator_node_lun_acl(
670 	struct se_lun *lun,
671 	struct se_lun_acl *lacl)
672 {
673 	struct se_portal_group *tpg = lun->lun_tpg;
674 	struct se_node_acl *nacl;
675 	struct se_dev_entry *deve;
676 
677 	nacl = lacl->se_lun_nacl;
678 	if (!nacl)
679 		return -EINVAL;
680 
681 	mutex_lock(&nacl->lun_entry_mutex);
682 	deve = target_nacl_find_deve(nacl, lacl->mapped_lun);
683 	if (deve)
684 		core_disable_device_list_for_node(lun, deve, nacl, tpg);
685 	mutex_unlock(&nacl->lun_entry_mutex);
686 
687 	pr_debug("%s_TPG[%hu]_LUN[%llu] - Removed ACL for"
688 		" InitiatorNode: %s Mapped LUN: %llu\n",
689 		tpg->se_tpg_tfo->fabric_name,
690 		tpg->se_tpg_tfo->tpg_get_tag(tpg), lun->unpacked_lun,
691 		nacl->initiatorname, lacl->mapped_lun);
692 
693 	return 0;
694 }
695 
696 void core_dev_free_initiator_node_lun_acl(
697 	struct se_portal_group *tpg,
698 	struct se_lun_acl *lacl)
699 {
700 	pr_debug("%s_TPG[%hu] - Freeing ACL for %s InitiatorNode: %s"
701 		" Mapped LUN: %llu\n", tpg->se_tpg_tfo->fabric_name,
702 		tpg->se_tpg_tfo->tpg_get_tag(tpg),
703 		tpg->se_tpg_tfo->fabric_name,
704 		lacl->se_lun_nacl->initiatorname, lacl->mapped_lun);
705 
706 	kfree(lacl);
707 }
708 
709 static void scsi_dump_inquiry(struct se_device *dev)
710 {
711 	struct t10_wwn *wwn = &dev->t10_wwn;
712 	int device_type = dev->transport->get_device_type(dev);
713 
714 	/*
715 	 * Print Linux/SCSI style INQUIRY formatting to the kernel ring buffer
716 	 */
717 	pr_debug("  Vendor: %-" __stringify(INQUIRY_VENDOR_LEN) "s\n",
718 		wwn->vendor);
719 	pr_debug("  Model: %-" __stringify(INQUIRY_MODEL_LEN) "s\n",
720 		wwn->model);
721 	pr_debug("  Revision: %-" __stringify(INQUIRY_REVISION_LEN) "s\n",
722 		wwn->revision);
723 	pr_debug("  Type:   %s ", scsi_device_type(device_type));
724 }
725 
726 struct se_device *target_alloc_device(struct se_hba *hba, const char *name)
727 {
728 	struct se_device *dev;
729 	struct se_lun *xcopy_lun;
730 
731 	dev = hba->backend->ops->alloc_device(hba, name);
732 	if (!dev)
733 		return NULL;
734 
735 	dev->se_hba = hba;
736 	dev->transport = hba->backend->ops;
737 	dev->transport_flags = dev->transport->transport_flags_default;
738 	dev->prot_length = sizeof(struct t10_pi_tuple);
739 	dev->hba_index = hba->hba_index;
740 
741 	INIT_LIST_HEAD(&dev->dev_sep_list);
742 	INIT_LIST_HEAD(&dev->dev_tmr_list);
743 	INIT_LIST_HEAD(&dev->delayed_cmd_list);
744 	INIT_LIST_HEAD(&dev->state_list);
745 	INIT_LIST_HEAD(&dev->qf_cmd_list);
746 	spin_lock_init(&dev->execute_task_lock);
747 	spin_lock_init(&dev->delayed_cmd_lock);
748 	spin_lock_init(&dev->dev_reservation_lock);
749 	spin_lock_init(&dev->se_port_lock);
750 	spin_lock_init(&dev->se_tmr_lock);
751 	spin_lock_init(&dev->qf_cmd_lock);
752 	sema_init(&dev->caw_sem, 1);
753 	INIT_LIST_HEAD(&dev->t10_wwn.t10_vpd_list);
754 	spin_lock_init(&dev->t10_wwn.t10_vpd_lock);
755 	INIT_LIST_HEAD(&dev->t10_pr.registration_list);
756 	INIT_LIST_HEAD(&dev->t10_pr.aptpl_reg_list);
757 	spin_lock_init(&dev->t10_pr.registration_lock);
758 	spin_lock_init(&dev->t10_pr.aptpl_reg_lock);
759 	INIT_LIST_HEAD(&dev->t10_alua.tg_pt_gps_list);
760 	spin_lock_init(&dev->t10_alua.tg_pt_gps_lock);
761 	INIT_LIST_HEAD(&dev->t10_alua.lba_map_list);
762 	spin_lock_init(&dev->t10_alua.lba_map_lock);
763 
764 	dev->t10_wwn.t10_dev = dev;
765 	dev->t10_alua.t10_dev = dev;
766 
767 	dev->dev_attrib.da_dev = dev;
768 	dev->dev_attrib.emulate_model_alias = DA_EMULATE_MODEL_ALIAS;
769 	dev->dev_attrib.emulate_dpo = 1;
770 	dev->dev_attrib.emulate_fua_write = 1;
771 	dev->dev_attrib.emulate_fua_read = 1;
772 	dev->dev_attrib.emulate_write_cache = DA_EMULATE_WRITE_CACHE;
773 	dev->dev_attrib.emulate_ua_intlck_ctrl = TARGET_UA_INTLCK_CTRL_CLEAR;
774 	dev->dev_attrib.emulate_tas = DA_EMULATE_TAS;
775 	dev->dev_attrib.emulate_tpu = DA_EMULATE_TPU;
776 	dev->dev_attrib.emulate_tpws = DA_EMULATE_TPWS;
777 	dev->dev_attrib.emulate_caw = DA_EMULATE_CAW;
778 	dev->dev_attrib.emulate_3pc = DA_EMULATE_3PC;
779 	dev->dev_attrib.emulate_pr = DA_EMULATE_PR;
780 	dev->dev_attrib.pi_prot_type = TARGET_DIF_TYPE0_PROT;
781 	dev->dev_attrib.enforce_pr_isids = DA_ENFORCE_PR_ISIDS;
782 	dev->dev_attrib.force_pr_aptpl = DA_FORCE_PR_APTPL;
783 	dev->dev_attrib.is_nonrot = DA_IS_NONROT;
784 	dev->dev_attrib.emulate_rest_reord = DA_EMULATE_REST_REORD;
785 	dev->dev_attrib.max_unmap_lba_count = DA_MAX_UNMAP_LBA_COUNT;
786 	dev->dev_attrib.max_unmap_block_desc_count =
787 		DA_MAX_UNMAP_BLOCK_DESC_COUNT;
788 	dev->dev_attrib.unmap_granularity = DA_UNMAP_GRANULARITY_DEFAULT;
789 	dev->dev_attrib.unmap_granularity_alignment =
790 				DA_UNMAP_GRANULARITY_ALIGNMENT_DEFAULT;
791 	dev->dev_attrib.unmap_zeroes_data =
792 				DA_UNMAP_ZEROES_DATA_DEFAULT;
793 	dev->dev_attrib.max_write_same_len = DA_MAX_WRITE_SAME_LEN;
794 
795 	xcopy_lun = &dev->xcopy_lun;
796 	rcu_assign_pointer(xcopy_lun->lun_se_dev, dev);
797 	init_completion(&xcopy_lun->lun_shutdown_comp);
798 	INIT_LIST_HEAD(&xcopy_lun->lun_deve_list);
799 	INIT_LIST_HEAD(&xcopy_lun->lun_dev_link);
800 	mutex_init(&xcopy_lun->lun_tg_pt_md_mutex);
801 	xcopy_lun->lun_tpg = &xcopy_pt_tpg;
802 
803 	/* Preload the default INQUIRY const values */
804 	strlcpy(dev->t10_wwn.vendor, "LIO-ORG", sizeof(dev->t10_wwn.vendor));
805 	strlcpy(dev->t10_wwn.model, dev->transport->inquiry_prod,
806 		sizeof(dev->t10_wwn.model));
807 	strlcpy(dev->t10_wwn.revision, dev->transport->inquiry_rev,
808 		sizeof(dev->t10_wwn.revision));
809 
810 	return dev;
811 }
812 
813 /*
814  * Check if the underlying struct block_device request_queue supports
815  * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM
816  * in ATA and we need to set TPE=1
817  */
818 bool target_configure_unmap_from_queue(struct se_dev_attrib *attrib,
819 				       struct request_queue *q)
820 {
821 	int block_size = queue_logical_block_size(q);
822 
823 	if (!blk_queue_discard(q))
824 		return false;
825 
826 	attrib->max_unmap_lba_count =
827 		q->limits.max_discard_sectors >> (ilog2(block_size) - 9);
828 	/*
829 	 * Currently hardcoded to 1 in Linux/SCSI code..
830 	 */
831 	attrib->max_unmap_block_desc_count = 1;
832 	attrib->unmap_granularity = q->limits.discard_granularity / block_size;
833 	attrib->unmap_granularity_alignment = q->limits.discard_alignment /
834 								block_size;
835 	attrib->unmap_zeroes_data = !!(q->limits.max_write_zeroes_sectors);
836 	return true;
837 }
838 EXPORT_SYMBOL(target_configure_unmap_from_queue);
839 
840 /*
841  * Convert from blocksize advertised to the initiator to the 512 byte
842  * units unconditionally used by the Linux block layer.
843  */
844 sector_t target_to_linux_sector(struct se_device *dev, sector_t lb)
845 {
846 	switch (dev->dev_attrib.block_size) {
847 	case 4096:
848 		return lb << 3;
849 	case 2048:
850 		return lb << 2;
851 	case 1024:
852 		return lb << 1;
853 	default:
854 		return lb;
855 	}
856 }
857 EXPORT_SYMBOL(target_to_linux_sector);
858 
859 struct devices_idr_iter {
860 	struct config_item *prev_item;
861 	int (*fn)(struct se_device *dev, void *data);
862 	void *data;
863 };
864 
865 static int target_devices_idr_iter(int id, void *p, void *data)
866 	 __must_hold(&device_mutex)
867 {
868 	struct devices_idr_iter *iter = data;
869 	struct se_device *dev = p;
870 	int ret;
871 
872 	config_item_put(iter->prev_item);
873 	iter->prev_item = NULL;
874 
875 	/*
876 	 * We add the device early to the idr, so it can be used
877 	 * by backend modules during configuration. We do not want
878 	 * to allow other callers to access partially setup devices,
879 	 * so we skip them here.
880 	 */
881 	if (!target_dev_configured(dev))
882 		return 0;
883 
884 	iter->prev_item = config_item_get_unless_zero(&dev->dev_group.cg_item);
885 	if (!iter->prev_item)
886 		return 0;
887 	mutex_unlock(&device_mutex);
888 
889 	ret = iter->fn(dev, iter->data);
890 
891 	mutex_lock(&device_mutex);
892 	return ret;
893 }
894 
895 /**
896  * target_for_each_device - iterate over configured devices
897  * @fn: iterator function
898  * @data: pointer to data that will be passed to fn
899  *
900  * fn must return 0 to continue looping over devices. non-zero will break
901  * from the loop and return that value to the caller.
902  */
903 int target_for_each_device(int (*fn)(struct se_device *dev, void *data),
904 			   void *data)
905 {
906 	struct devices_idr_iter iter = { .fn = fn, .data = data };
907 	int ret;
908 
909 	mutex_lock(&device_mutex);
910 	ret = idr_for_each(&devices_idr, target_devices_idr_iter, &iter);
911 	mutex_unlock(&device_mutex);
912 	config_item_put(iter.prev_item);
913 	return ret;
914 }
915 
916 int target_configure_device(struct se_device *dev)
917 {
918 	struct se_hba *hba = dev->se_hba;
919 	int ret, id;
920 
921 	if (target_dev_configured(dev)) {
922 		pr_err("se_dev->se_dev_ptr already set for storage"
923 				" object\n");
924 		return -EEXIST;
925 	}
926 
927 	/*
928 	 * Add early so modules like tcmu can use during its
929 	 * configuration.
930 	 */
931 	mutex_lock(&device_mutex);
932 	/*
933 	 * Use cyclic to try and avoid collisions with devices
934 	 * that were recently removed.
935 	 */
936 	id = idr_alloc_cyclic(&devices_idr, dev, 0, INT_MAX, GFP_KERNEL);
937 	mutex_unlock(&device_mutex);
938 	if (id < 0) {
939 		ret = -ENOMEM;
940 		goto out;
941 	}
942 	dev->dev_index = id;
943 
944 	ret = dev->transport->configure_device(dev);
945 	if (ret)
946 		goto out_free_index;
947 	/*
948 	 * XXX: there is not much point to have two different values here..
949 	 */
950 	dev->dev_attrib.block_size = dev->dev_attrib.hw_block_size;
951 	dev->dev_attrib.queue_depth = dev->dev_attrib.hw_queue_depth;
952 
953 	/*
954 	 * Align max_hw_sectors down to PAGE_SIZE I/O transfers
955 	 */
956 	dev->dev_attrib.hw_max_sectors =
957 		se_dev_align_max_sectors(dev->dev_attrib.hw_max_sectors,
958 					 dev->dev_attrib.hw_block_size);
959 	dev->dev_attrib.optimal_sectors = dev->dev_attrib.hw_max_sectors;
960 
961 	dev->creation_time = get_jiffies_64();
962 
963 	ret = core_setup_alua(dev);
964 	if (ret)
965 		goto out_destroy_device;
966 
967 	/*
968 	 * Setup work_queue for QUEUE_FULL
969 	 */
970 	INIT_WORK(&dev->qf_work_queue, target_qf_do_work);
971 
972 	scsi_dump_inquiry(dev);
973 
974 	spin_lock(&hba->device_lock);
975 	hba->dev_count++;
976 	spin_unlock(&hba->device_lock);
977 
978 	dev->dev_flags |= DF_CONFIGURED;
979 
980 	return 0;
981 
982 out_destroy_device:
983 	dev->transport->destroy_device(dev);
984 out_free_index:
985 	mutex_lock(&device_mutex);
986 	idr_remove(&devices_idr, dev->dev_index);
987 	mutex_unlock(&device_mutex);
988 out:
989 	se_release_vpd_for_dev(dev);
990 	return ret;
991 }
992 
993 void target_free_device(struct se_device *dev)
994 {
995 	struct se_hba *hba = dev->se_hba;
996 
997 	WARN_ON(!list_empty(&dev->dev_sep_list));
998 
999 	if (target_dev_configured(dev)) {
1000 		dev->transport->destroy_device(dev);
1001 
1002 		mutex_lock(&device_mutex);
1003 		idr_remove(&devices_idr, dev->dev_index);
1004 		mutex_unlock(&device_mutex);
1005 
1006 		spin_lock(&hba->device_lock);
1007 		hba->dev_count--;
1008 		spin_unlock(&hba->device_lock);
1009 	}
1010 
1011 	core_alua_free_lu_gp_mem(dev);
1012 	core_alua_set_lba_map(dev, NULL, 0, 0);
1013 	core_scsi3_free_all_registrations(dev);
1014 	se_release_vpd_for_dev(dev);
1015 
1016 	if (dev->transport->free_prot)
1017 		dev->transport->free_prot(dev);
1018 
1019 	dev->transport->free_device(dev);
1020 }
1021 
1022 int core_dev_setup_virtual_lun0(void)
1023 {
1024 	struct se_hba *hba;
1025 	struct se_device *dev;
1026 	char buf[] = "rd_pages=8,rd_nullio=1";
1027 	int ret;
1028 
1029 	hba = core_alloc_hba("rd_mcp", 0, HBA_FLAGS_INTERNAL_USE);
1030 	if (IS_ERR(hba))
1031 		return PTR_ERR(hba);
1032 
1033 	dev = target_alloc_device(hba, "virt_lun0");
1034 	if (!dev) {
1035 		ret = -ENOMEM;
1036 		goto out_free_hba;
1037 	}
1038 
1039 	hba->backend->ops->set_configfs_dev_params(dev, buf, sizeof(buf));
1040 
1041 	ret = target_configure_device(dev);
1042 	if (ret)
1043 		goto out_free_se_dev;
1044 
1045 	lun0_hba = hba;
1046 	g_lun0_dev = dev;
1047 	return 0;
1048 
1049 out_free_se_dev:
1050 	target_free_device(dev);
1051 out_free_hba:
1052 	core_delete_hba(hba);
1053 	return ret;
1054 }
1055 
1056 
1057 void core_dev_release_virtual_lun0(void)
1058 {
1059 	struct se_hba *hba = lun0_hba;
1060 
1061 	if (!hba)
1062 		return;
1063 
1064 	if (g_lun0_dev)
1065 		target_free_device(g_lun0_dev);
1066 	core_delete_hba(hba);
1067 }
1068 
1069 /*
1070  * Common CDB parsing for kernel and user passthrough.
1071  */
1072 sense_reason_t
1073 passthrough_parse_cdb(struct se_cmd *cmd,
1074 	sense_reason_t (*exec_cmd)(struct se_cmd *cmd))
1075 {
1076 	unsigned char *cdb = cmd->t_task_cdb;
1077 	struct se_device *dev = cmd->se_dev;
1078 	unsigned int size;
1079 
1080 	/*
1081 	 * For REPORT LUNS we always need to emulate the response, for everything
1082 	 * else, pass it up.
1083 	 */
1084 	if (cdb[0] == REPORT_LUNS) {
1085 		cmd->execute_cmd = spc_emulate_report_luns;
1086 		return TCM_NO_SENSE;
1087 	}
1088 
1089 	/*
1090 	 * With emulate_pr disabled, all reservation requests should fail,
1091 	 * regardless of whether or not TRANSPORT_FLAG_PASSTHROUGH_PGR is set.
1092 	 */
1093 	if (!dev->dev_attrib.emulate_pr &&
1094 	    ((cdb[0] == PERSISTENT_RESERVE_IN) ||
1095 	     (cdb[0] == PERSISTENT_RESERVE_OUT) ||
1096 	     (cdb[0] == RELEASE || cdb[0] == RELEASE_10) ||
1097 	     (cdb[0] == RESERVE || cdb[0] == RESERVE_10))) {
1098 		return TCM_UNSUPPORTED_SCSI_OPCODE;
1099 	}
1100 
1101 	/*
1102 	 * For PERSISTENT RESERVE IN/OUT, RELEASE, and RESERVE we need to
1103 	 * emulate the response, since tcmu does not have the information
1104 	 * required to process these commands.
1105 	 */
1106 	if (!(dev->transport_flags &
1107 	      TRANSPORT_FLAG_PASSTHROUGH_PGR)) {
1108 		if (cdb[0] == PERSISTENT_RESERVE_IN) {
1109 			cmd->execute_cmd = target_scsi3_emulate_pr_in;
1110 			size = get_unaligned_be16(&cdb[7]);
1111 			return target_cmd_size_check(cmd, size);
1112 		}
1113 		if (cdb[0] == PERSISTENT_RESERVE_OUT) {
1114 			cmd->execute_cmd = target_scsi3_emulate_pr_out;
1115 			size = get_unaligned_be32(&cdb[5]);
1116 			return target_cmd_size_check(cmd, size);
1117 		}
1118 
1119 		if (cdb[0] == RELEASE || cdb[0] == RELEASE_10) {
1120 			cmd->execute_cmd = target_scsi2_reservation_release;
1121 			if (cdb[0] == RELEASE_10)
1122 				size = get_unaligned_be16(&cdb[7]);
1123 			else
1124 				size = cmd->data_length;
1125 			return target_cmd_size_check(cmd, size);
1126 		}
1127 		if (cdb[0] == RESERVE || cdb[0] == RESERVE_10) {
1128 			cmd->execute_cmd = target_scsi2_reservation_reserve;
1129 			if (cdb[0] == RESERVE_10)
1130 				size = get_unaligned_be16(&cdb[7]);
1131 			else
1132 				size = cmd->data_length;
1133 			return target_cmd_size_check(cmd, size);
1134 		}
1135 	}
1136 
1137 	/* Set DATA_CDB flag for ops that should have it */
1138 	switch (cdb[0]) {
1139 	case READ_6:
1140 	case READ_10:
1141 	case READ_12:
1142 	case READ_16:
1143 	case WRITE_6:
1144 	case WRITE_10:
1145 	case WRITE_12:
1146 	case WRITE_16:
1147 	case WRITE_VERIFY:
1148 	case WRITE_VERIFY_12:
1149 	case WRITE_VERIFY_16:
1150 	case COMPARE_AND_WRITE:
1151 	case XDWRITEREAD_10:
1152 		cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
1153 		break;
1154 	case VARIABLE_LENGTH_CMD:
1155 		switch (get_unaligned_be16(&cdb[8])) {
1156 		case READ_32:
1157 		case WRITE_32:
1158 		case WRITE_VERIFY_32:
1159 		case XDWRITEREAD_32:
1160 			cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
1161 			break;
1162 		}
1163 	}
1164 
1165 	cmd->execute_cmd = exec_cmd;
1166 
1167 	return TCM_NO_SENSE;
1168 }
1169 EXPORT_SYMBOL(passthrough_parse_cdb);
1170