Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
4 * Copyright (C) 2004 - 2006 Red Hat, Inc. All rights reserved.
5 *
6 * This file is released under the GPL.
7 */
8
9#include "dm-core.h"
10#include "dm-ima.h"
11#include <linux/module.h>
12#include <linux/vmalloc.h>
13#include <linux/miscdevice.h>
14#include <linux/sched/mm.h>
15#include <linux/init.h>
16#include <linux/wait.h>
17#include <linux/slab.h>
18#include <linux/rbtree.h>
19#include <linux/dm-ioctl.h>
20#include <linux/hdreg.h>
21#include <linux/compat.h>
22#include <linux/nospec.h>
23
24#include <linux/uaccess.h>
25#include <linux/ima.h>
26
27#define DM_MSG_PREFIX "ioctl"
28#define DM_DRIVER_EMAIL "dm-devel@lists.linux.dev"
29
30struct dm_file {
31 /*
32 * poll will wait until the global event number is greater than
33 * this value.
34 */
35 volatile unsigned int global_event_nr;
36};
37
38/*
39 *---------------------------------------------------------------
40 * The ioctl interface needs to be able to look up devices by
41 * name or uuid.
42 *---------------------------------------------------------------
43 */
44struct hash_cell {
45 struct rb_node name_node;
46 struct rb_node uuid_node;
47 bool name_set;
48 bool uuid_set;
49
50 char *name;
51 char *uuid;
52 struct mapped_device *md;
53 struct dm_table *new_map;
54};
55
56struct vers_iter {
57 size_t param_size;
58 struct dm_target_versions *vers, *old_vers;
59 char *end;
60 uint32_t flags;
61};
62
63
64static struct rb_root name_rb_tree = RB_ROOT;
65static struct rb_root uuid_rb_tree = RB_ROOT;
66
67#define DM_REMOVE_KEEP_OPEN_DEVICES 1
68#define DM_REMOVE_MARK_DEFERRED 2
69#define DM_REMOVE_ONLY_DEFERRED 4
70#define DM_REMOVE_INTERRUPTIBLE 8
71static int dm_hash_remove_all(unsigned flags);
72
73/*
74 * Guards access to both hash tables.
75 */
76static DECLARE_RWSEM(_hash_lock);
77
78/*
79 * Protects use of mdptr to obtain hash cell name and uuid from mapped device.
80 */
81static DEFINE_MUTEX(dm_hash_cells_mutex);
82
83static void dm_hash_exit(void)
84{
85 dm_hash_remove_all(0);
86}
87
88/*
89 *---------------------------------------------------------------
90 * Code for looking up a device by name
91 *---------------------------------------------------------------
92 */
93static struct hash_cell *__get_name_cell(const char *str)
94{
95 struct rb_node *n = name_rb_tree.rb_node;
96
97 while (n) {
98 struct hash_cell *hc = container_of(n, struct hash_cell, name_node);
99 int c;
100
101 c = strcmp(hc->name, str);
102 if (!c) {
103 dm_get(hc->md);
104 return hc;
105 }
106 n = c >= 0 ? n->rb_left : n->rb_right;
107 }
108
109 return NULL;
110}
111
112static struct hash_cell *__get_uuid_cell(const char *str)
113{
114 struct rb_node *n = uuid_rb_tree.rb_node;
115
116 while (n) {
117 struct hash_cell *hc = container_of(n, struct hash_cell, uuid_node);
118 int c;
119
120 c = strcmp(hc->uuid, str);
121 if (!c) {
122 dm_get(hc->md);
123 return hc;
124 }
125 n = c >= 0 ? n->rb_left : n->rb_right;
126 }
127
128 return NULL;
129}
130
131static void __unlink_name(struct hash_cell *hc)
132{
133 if (hc->name_set) {
134 hc->name_set = false;
135 rb_erase(&hc->name_node, &name_rb_tree);
136 }
137}
138
139static void __unlink_uuid(struct hash_cell *hc)
140{
141 if (hc->uuid_set) {
142 hc->uuid_set = false;
143 rb_erase(&hc->uuid_node, &uuid_rb_tree);
144 }
145}
146
147static void __link_name(struct hash_cell *new_hc)
148{
149 struct rb_node **n, *parent;
150
151 __unlink_name(new_hc);
152
153 new_hc->name_set = true;
154
155 n = &name_rb_tree.rb_node;
156 parent = NULL;
157
158 while (*n) {
159 struct hash_cell *hc = container_of(*n, struct hash_cell, name_node);
160 int c;
161
162 c = strcmp(hc->name, new_hc->name);
163 BUG_ON(!c);
164 parent = *n;
165 n = c >= 0 ? &hc->name_node.rb_left : &hc->name_node.rb_right;
166 }
167
168 rb_link_node(&new_hc->name_node, parent, n);
169 rb_insert_color(&new_hc->name_node, &name_rb_tree);
170}
171
172static void __link_uuid(struct hash_cell *new_hc)
173{
174 struct rb_node **n, *parent;
175
176 __unlink_uuid(new_hc);
177
178 new_hc->uuid_set = true;
179
180 n = &uuid_rb_tree.rb_node;
181 parent = NULL;
182
183 while (*n) {
184 struct hash_cell *hc = container_of(*n, struct hash_cell, uuid_node);
185 int c;
186
187 c = strcmp(hc->uuid, new_hc->uuid);
188 BUG_ON(!c);
189 parent = *n;
190 n = c > 0 ? &hc->uuid_node.rb_left : &hc->uuid_node.rb_right;
191 }
192
193 rb_link_node(&new_hc->uuid_node, parent, n);
194 rb_insert_color(&new_hc->uuid_node, &uuid_rb_tree);
195}
196
197static struct hash_cell *__get_dev_cell(uint64_t dev)
198{
199 struct mapped_device *md;
200 struct hash_cell *hc;
201
202 md = dm_get_md(huge_decode_dev(dev));
203 if (!md)
204 return NULL;
205
206 hc = dm_get_mdptr(md);
207 if (!hc) {
208 dm_put(md);
209 return NULL;
210 }
211
212 return hc;
213}
214
215/*
216 *---------------------------------------------------------------
217 * Inserting, removing and renaming a device.
218 *---------------------------------------------------------------
219 */
220static struct hash_cell *alloc_cell(const char *name, const char *uuid,
221 struct mapped_device *md)
222{
223 struct hash_cell *hc;
224
225 hc = kmalloc_obj(*hc);
226 if (!hc)
227 return NULL;
228
229 hc->name = kstrdup(name, GFP_KERNEL);
230 if (!hc->name) {
231 kfree(hc);
232 return NULL;
233 }
234
235 if (!uuid)
236 hc->uuid = NULL;
237
238 else {
239 hc->uuid = kstrdup(uuid, GFP_KERNEL);
240 if (!hc->uuid) {
241 kfree(hc->name);
242 kfree(hc);
243 return NULL;
244 }
245 }
246
247 hc->name_set = hc->uuid_set = false;
248 hc->md = md;
249 hc->new_map = NULL;
250 return hc;
251}
252
253static void free_cell(struct hash_cell *hc)
254{
255 if (hc) {
256 kfree(hc->name);
257 kfree(hc->uuid);
258 kfree(hc);
259 }
260}
261
262/*
263 * The kdev_t and uuid of a device can never change once it is
264 * initially inserted.
265 */
266static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
267{
268 struct hash_cell *cell, *hc;
269
270 /*
271 * Allocate the new cells.
272 */
273 cell = alloc_cell(name, uuid, md);
274 if (!cell)
275 return -ENOMEM;
276
277 /*
278 * Insert the cell into both hash tables.
279 */
280 down_write(&_hash_lock);
281 hc = __get_name_cell(name);
282 if (hc) {
283 dm_put(hc->md);
284 goto bad;
285 }
286
287 __link_name(cell);
288
289 if (uuid) {
290 hc = __get_uuid_cell(uuid);
291 if (hc) {
292 __unlink_name(cell);
293 dm_put(hc->md);
294 goto bad;
295 }
296 __link_uuid(cell);
297 }
298 dm_get(md);
299 mutex_lock(&dm_hash_cells_mutex);
300 dm_set_mdptr(md, cell);
301 mutex_unlock(&dm_hash_cells_mutex);
302 up_write(&_hash_lock);
303
304 return 0;
305
306 bad:
307 up_write(&_hash_lock);
308 free_cell(cell);
309 return -EBUSY;
310}
311
312static struct dm_table *__hash_remove(struct hash_cell *hc)
313{
314 struct dm_table *table;
315 int srcu_idx;
316
317 lockdep_assert_held(&_hash_lock);
318
319 /* remove from the dev trees */
320 __unlink_name(hc);
321 __unlink_uuid(hc);
322 mutex_lock(&dm_hash_cells_mutex);
323 dm_set_mdptr(hc->md, NULL);
324 mutex_unlock(&dm_hash_cells_mutex);
325
326 table = dm_get_live_table(hc->md, &srcu_idx);
327 if (table)
328 dm_table_event(table);
329 dm_put_live_table(hc->md, srcu_idx);
330
331 table = NULL;
332 if (hc->new_map)
333 table = hc->new_map;
334 dm_put(hc->md);
335 free_cell(hc);
336
337 return table;
338}
339
340static int dm_hash_remove_all(unsigned flags)
341{
342 int dev_skipped;
343 struct rb_node *n;
344 struct hash_cell *hc;
345 struct mapped_device *md;
346 struct dm_table *t;
347
348retry:
349 dev_skipped = 0;
350
351 down_write(&_hash_lock);
352
353 for (n = rb_first(&name_rb_tree); n; n = rb_next(n)) {
354 if (flags & DM_REMOVE_INTERRUPTIBLE && fatal_signal_pending(current)) {
355 up_write(&_hash_lock);
356 return -EINTR;
357 }
358
359 hc = container_of(n, struct hash_cell, name_node);
360 md = hc->md;
361 dm_get(md);
362
363 if (flags & DM_REMOVE_KEEP_OPEN_DEVICES &&
364 dm_lock_for_deletion(md, !!(flags & DM_REMOVE_MARK_DEFERRED), !!(flags & DM_REMOVE_ONLY_DEFERRED))) {
365 dm_put(md);
366 dev_skipped++;
367 continue;
368 }
369
370 t = __hash_remove(hc);
371
372 up_write(&_hash_lock);
373
374 if (t) {
375 dm_sync_table(md);
376 dm_table_destroy(t);
377 }
378 dm_ima_measure_on_device_remove(md, true);
379 dm_put(md);
380 if (likely(flags & DM_REMOVE_KEEP_OPEN_DEVICES))
381 dm_destroy(md);
382 else
383 dm_destroy_immediate(md);
384
385 /*
386 * Some mapped devices may be using other mapped
387 * devices, so repeat until we make no further
388 * progress. If a new mapped device is created
389 * here it will also get removed.
390 */
391 goto retry;
392 }
393
394 up_write(&_hash_lock);
395
396 if (dev_skipped && !(flags & DM_REMOVE_ONLY_DEFERRED))
397 DMWARN("remove_all left %d open device(s)", dev_skipped);
398
399 return 0;
400}
401
402/*
403 * Set the uuid of a hash_cell that isn't already set.
404 */
405static void __set_cell_uuid(struct hash_cell *hc, char *new_uuid)
406{
407 mutex_lock(&dm_hash_cells_mutex);
408 hc->uuid = new_uuid;
409 mutex_unlock(&dm_hash_cells_mutex);
410
411 __link_uuid(hc);
412}
413
414/*
415 * Changes the name of a hash_cell and returns the old name for
416 * the caller to free.
417 */
418static char *__change_cell_name(struct hash_cell *hc, char *new_name)
419{
420 char *old_name;
421
422 /*
423 * Rename and move the name cell.
424 */
425 __unlink_name(hc);
426 old_name = hc->name;
427
428 mutex_lock(&dm_hash_cells_mutex);
429 hc->name = new_name;
430 mutex_unlock(&dm_hash_cells_mutex);
431
432 __link_name(hc);
433
434 return old_name;
435}
436
437static struct mapped_device *dm_hash_rename(struct dm_ioctl *param,
438 const char *new)
439{
440 char *new_data, *old_name = NULL;
441 struct hash_cell *hc;
442 struct dm_table *table;
443 struct mapped_device *md;
444 unsigned int change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
445 int srcu_idx;
446
447 /*
448 * duplicate new.
449 */
450 new_data = kstrdup(new, GFP_KERNEL);
451 if (!new_data)
452 return ERR_PTR(-ENOMEM);
453
454 down_write(&_hash_lock);
455
456 /*
457 * Is new free ?
458 */
459 if (change_uuid)
460 hc = __get_uuid_cell(new);
461 else
462 hc = __get_name_cell(new);
463
464 if (hc) {
465 DMERR("Unable to change %s on mapped device %s to one that already exists: %s",
466 change_uuid ? "uuid" : "name",
467 param->name, new);
468 dm_put(hc->md);
469 up_write(&_hash_lock);
470 kfree(new_data);
471 return ERR_PTR(-EBUSY);
472 }
473
474 /*
475 * Is there such a device as 'old' ?
476 */
477 hc = __get_name_cell(param->name);
478 if (!hc) {
479 DMERR("Unable to rename non-existent device, %s to %s%s",
480 param->name, change_uuid ? "uuid " : "", new);
481 up_write(&_hash_lock);
482 kfree(new_data);
483 return ERR_PTR(-ENXIO);
484 }
485
486 /*
487 * Does this device already have a uuid?
488 */
489 if (change_uuid && hc->uuid) {
490 DMERR("Unable to change uuid of mapped device %s to %s "
491 "because uuid is already set to %s",
492 param->name, new, hc->uuid);
493 dm_put(hc->md);
494 up_write(&_hash_lock);
495 kfree(new_data);
496 return ERR_PTR(-EINVAL);
497 }
498
499 if (change_uuid)
500 __set_cell_uuid(hc, new_data);
501 else
502 old_name = __change_cell_name(hc, new_data);
503
504 /*
505 * Wake up any dm event waiters.
506 */
507 table = dm_get_live_table(hc->md, &srcu_idx);
508 if (table)
509 dm_table_event(table);
510 dm_put_live_table(hc->md, srcu_idx);
511
512 if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, param->event_nr, false))
513 param->flags |= DM_UEVENT_GENERATED_FLAG;
514
515 md = hc->md;
516
517 dm_ima_measure_on_device_rename(md);
518
519 up_write(&_hash_lock);
520 kfree(old_name);
521
522 return md;
523}
524
525void dm_deferred_remove(void)
526{
527 dm_hash_remove_all(DM_REMOVE_KEEP_OPEN_DEVICES | DM_REMOVE_ONLY_DEFERRED);
528}
529
530/*
531 *---------------------------------------------------------------
532 * Implementation of the ioctl commands
533 *---------------------------------------------------------------
534 */
535/*
536 * All the ioctl commands get dispatched to functions with this
537 * prototype.
538 */
539typedef int (*ioctl_fn)(struct file *filp, struct dm_ioctl *param, size_t param_size);
540
541static int remove_all(struct file *filp, struct dm_ioctl *param, size_t param_size)
542{
543 int r;
544 int flags = DM_REMOVE_KEEP_OPEN_DEVICES | DM_REMOVE_INTERRUPTIBLE;
545 if (param->flags & DM_DEFERRED_REMOVE)
546 flags |= DM_REMOVE_MARK_DEFERRED;
547 r = dm_hash_remove_all(flags);
548 param->data_size = 0;
549 return r;
550}
551
552/*
553 * Round up the ptr to an 8-byte boundary.
554 */
555#define ALIGN_MASK 7
556static inline size_t align_val(size_t val)
557{
558 return (val + ALIGN_MASK) & ~ALIGN_MASK;
559}
560static inline void *align_ptr(void *ptr)
561{
562 return (void *)align_val((size_t)ptr);
563}
564
565/*
566 * Retrieves the data payload buffer from an already allocated
567 * struct dm_ioctl.
568 */
569static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
570 size_t *len)
571{
572 param->data_start = align_ptr(param + 1) - (void *) param;
573
574 if (param->data_start < param_size)
575 *len = param_size - param->data_start;
576 else
577 *len = 0;
578
579 return ((void *) param) + param->data_start;
580}
581
582static bool filter_device(struct hash_cell *hc, const char *pfx_name, const char *pfx_uuid)
583{
584 const char *val;
585 size_t val_len, pfx_len;
586
587 val = hc->name;
588 val_len = strlen(val);
589 pfx_len = strnlen(pfx_name, DM_NAME_LEN);
590 if (pfx_len > val_len)
591 return false;
592 if (memcmp(val, pfx_name, pfx_len))
593 return false;
594
595 val = hc->uuid ? hc->uuid : "";
596 val_len = strlen(val);
597 pfx_len = strnlen(pfx_uuid, DM_UUID_LEN);
598 if (pfx_len > val_len)
599 return false;
600 if (memcmp(val, pfx_uuid, pfx_len))
601 return false;
602
603 return true;
604}
605
606static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_size)
607{
608 struct rb_node *n;
609 struct hash_cell *hc;
610 size_t len, needed = 0;
611 struct gendisk *disk;
612 struct dm_name_list *orig_nl, *nl, *old_nl = NULL;
613 uint32_t *event_nr;
614
615 down_write(&_hash_lock);
616
617 /*
618 * Loop through all the devices working out how much
619 * space we need.
620 */
621 for (n = rb_first(&name_rb_tree); n; n = rb_next(n)) {
622 hc = container_of(n, struct hash_cell, name_node);
623 if (!filter_device(hc, param->name, param->uuid))
624 continue;
625 needed += align_val(offsetof(struct dm_name_list, name) + strlen(hc->name) + 1);
626 needed += align_val(sizeof(uint32_t) * 2);
627 if (param->flags & DM_UUID_FLAG && hc->uuid)
628 needed += align_val(strlen(hc->uuid) + 1);
629 }
630
631 /*
632 * Grab our output buffer.
633 */
634 nl = orig_nl = get_result_buffer(param, param_size, &len);
635 if (len < needed || len < sizeof(nl->dev)) {
636 param->flags |= DM_BUFFER_FULL_FLAG;
637 goto out;
638 }
639 param->data_size = param->data_start + needed;
640
641 nl->dev = 0; /* Flags no data */
642
643 /*
644 * Now loop through filling out the names.
645 */
646 for (n = rb_first(&name_rb_tree); n; n = rb_next(n)) {
647 void *uuid_ptr;
648
649 hc = container_of(n, struct hash_cell, name_node);
650 if (!filter_device(hc, param->name, param->uuid))
651 continue;
652 if (old_nl)
653 old_nl->next = (uint32_t) ((void *) nl -
654 (void *) old_nl);
655 disk = dm_disk(hc->md);
656 nl->dev = huge_encode_dev(disk_devt(disk));
657 nl->next = 0;
658 strcpy(nl->name, hc->name);
659
660 old_nl = nl;
661 event_nr = align_ptr(nl->name + strlen(hc->name) + 1);
662 event_nr[0] = dm_get_event_nr(hc->md);
663 event_nr[1] = 0;
664 uuid_ptr = align_ptr(event_nr + 2);
665 if (param->flags & DM_UUID_FLAG) {
666 if (hc->uuid) {
667 event_nr[1] |= DM_NAME_LIST_FLAG_HAS_UUID;
668 strcpy(uuid_ptr, hc->uuid);
669 uuid_ptr = align_ptr(uuid_ptr + strlen(hc->uuid) + 1);
670 } else {
671 event_nr[1] |= DM_NAME_LIST_FLAG_DOESNT_HAVE_UUID;
672 }
673 }
674 nl = uuid_ptr;
675 }
676 /*
677 * If mismatch happens, security may be compromised due to buffer
678 * overflow, so it's better to crash.
679 */
680 BUG_ON((char *)nl - (char *)orig_nl != needed);
681
682 out:
683 up_write(&_hash_lock);
684 return 0;
685}
686
687static void list_version_get_needed(struct target_type *tt, void *needed_param)
688{
689 size_t *needed = needed_param;
690
691 *needed += sizeof(struct dm_target_versions);
692 *needed += strlen(tt->name) + 1;
693 *needed += ALIGN_MASK;
694}
695
696static void list_version_get_info(struct target_type *tt, void *param)
697{
698 struct vers_iter *info = param;
699
700 /* Check space - it might have changed since the first iteration */
701 if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 > info->end) {
702 info->flags = DM_BUFFER_FULL_FLAG;
703 return;
704 }
705
706 if (info->old_vers)
707 info->old_vers->next = (uint32_t) ((void *)info->vers - (void *)info->old_vers);
708
709 info->vers->version[0] = tt->version[0];
710 info->vers->version[1] = tt->version[1];
711 info->vers->version[2] = tt->version[2];
712 info->vers->next = 0;
713 strcpy(info->vers->name, tt->name);
714
715 info->old_vers = info->vers;
716 info->vers = align_ptr((void *)(info->vers + 1) + strlen(tt->name) + 1);
717}
718
719static int __list_versions(struct dm_ioctl *param, size_t param_size, const char *name)
720{
721 size_t len, needed = 0;
722 struct dm_target_versions *vers;
723 struct vers_iter iter_info;
724 struct target_type *tt = NULL;
725
726 if (name) {
727 tt = dm_get_target_type(name);
728 if (!tt)
729 return -EINVAL;
730 }
731
732 /*
733 * Loop through all the devices working out how much
734 * space we need.
735 */
736 if (!tt)
737 dm_target_iterate(list_version_get_needed, &needed);
738 else
739 list_version_get_needed(tt, &needed);
740
741 /*
742 * Grab our output buffer.
743 */
744 vers = get_result_buffer(param, param_size, &len);
745 if (len < needed) {
746 param->flags |= DM_BUFFER_FULL_FLAG;
747 goto out;
748 }
749 param->data_size = param->data_start + needed;
750
751 iter_info.param_size = param_size;
752 iter_info.old_vers = NULL;
753 iter_info.vers = vers;
754 iter_info.flags = 0;
755 iter_info.end = (char *)vers + needed;
756
757 /*
758 * Now loop through filling out the names & versions.
759 */
760 if (!tt)
761 dm_target_iterate(list_version_get_info, &iter_info);
762 else
763 list_version_get_info(tt, &iter_info);
764 param->flags |= iter_info.flags;
765
766 out:
767 if (tt)
768 dm_put_target_type(tt);
769 return 0;
770}
771
772static int list_versions(struct file *filp, struct dm_ioctl *param, size_t param_size)
773{
774 return __list_versions(param, param_size, NULL);
775}
776
777static int get_target_version(struct file *filp, struct dm_ioctl *param, size_t param_size)
778{
779 return __list_versions(param, param_size, param->name);
780}
781
782static int check_name(const char *name)
783{
784 if (strchr(name, '/')) {
785 DMERR("device name cannot contain '/'");
786 return -EINVAL;
787 }
788
789 if (strcmp(name, DM_CONTROL_NODE) == 0 ||
790 strcmp(name, ".") == 0 ||
791 strcmp(name, "..") == 0) {
792 DMERR("device name cannot be \"%s\", \".\", or \"..\"", DM_CONTROL_NODE);
793 return -EINVAL;
794 }
795
796 return 0;
797}
798
799/*
800 * On successful return, the caller must not attempt to acquire
801 * _hash_lock without first calling dm_put_live_table, because dm_table_destroy
802 * waits for this dm_put_live_table and could be called under this lock.
803 */
804static struct dm_table *dm_get_inactive_table(struct mapped_device *md, int *srcu_idx)
805{
806 struct hash_cell *hc;
807 struct dm_table *table = NULL;
808
809 /* increment rcu count, we don't care about the table pointer */
810 dm_get_live_table(md, srcu_idx);
811
812 down_read(&_hash_lock);
813 hc = dm_get_mdptr(md);
814 if (!hc) {
815 DMERR("device has been removed from the dev hash table.");
816 goto out;
817 }
818
819 table = hc->new_map;
820
821out:
822 up_read(&_hash_lock);
823
824 return table;
825}
826
827static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md,
828 struct dm_ioctl *param,
829 int *srcu_idx)
830{
831 return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ?
832 dm_get_inactive_table(md, srcu_idx) : dm_get_live_table(md, srcu_idx);
833}
834
835/*
836 * Fills in a dm_ioctl structure, ready for sending back to
837 * userland.
838 */
839static void __dev_status(struct mapped_device *md, struct dm_ioctl *param)
840{
841 struct gendisk *disk = dm_disk(md);
842 struct dm_table *table;
843 int srcu_idx;
844
845 param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
846 DM_ACTIVE_PRESENT_FLAG | DM_INTERNAL_SUSPEND_FLAG);
847
848 if (dm_suspended_md(md))
849 param->flags |= DM_SUSPEND_FLAG;
850
851 if (dm_suspended_internally_md(md))
852 param->flags |= DM_INTERNAL_SUSPEND_FLAG;
853
854 if (dm_test_deferred_remove_flag(md))
855 param->flags |= DM_DEFERRED_REMOVE;
856
857 param->dev = huge_encode_dev(disk_devt(disk));
858
859 /*
860 * Yes, this will be out of date by the time it gets back
861 * to userland, but it is still very useful for
862 * debugging.
863 */
864 param->open_count = dm_open_count(md);
865
866 param->event_nr = dm_get_event_nr(md);
867 param->target_count = 0;
868
869 table = dm_get_live_table(md, &srcu_idx);
870 if (table) {
871 if (!(param->flags & DM_QUERY_INACTIVE_TABLE_FLAG)) {
872 if (get_disk_ro(disk))
873 param->flags |= DM_READONLY_FLAG;
874 param->target_count = table->num_targets;
875 }
876
877 param->flags |= DM_ACTIVE_PRESENT_FLAG;
878 }
879 dm_put_live_table(md, srcu_idx);
880
881 if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) {
882 int srcu_idx;
883
884 table = dm_get_inactive_table(md, &srcu_idx);
885 if (table) {
886 if (!(dm_table_get_mode(table) & BLK_OPEN_WRITE))
887 param->flags |= DM_READONLY_FLAG;
888 param->target_count = table->num_targets;
889 }
890 dm_put_live_table(md, srcu_idx);
891 }
892}
893
894static int dev_create(struct file *filp, struct dm_ioctl *param, size_t param_size)
895{
896 int r, m = DM_ANY_MINOR;
897 struct mapped_device *md;
898
899 r = check_name(param->name);
900 if (r)
901 return r;
902
903 if (param->flags & DM_PERSISTENT_DEV_FLAG)
904 m = MINOR(huge_decode_dev(param->dev));
905
906 r = dm_create(m, &md);
907 if (r)
908 return r;
909
910 r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
911 if (r) {
912 dm_put(md);
913 dm_destroy(md);
914 return r;
915 }
916
917 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
918
919 __dev_status(md, param);
920
921 dm_put(md);
922
923 return 0;
924}
925
926/*
927 * Always use UUID for lookups if it's present, otherwise use name or dev.
928 */
929static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
930{
931 struct hash_cell *hc = NULL;
932
933 if (*param->uuid) {
934 if (*param->name || param->dev) {
935 DMERR("Invalid ioctl structure: uuid %s, name %s, dev %llx",
936 param->uuid, param->name, (unsigned long long)param->dev);
937 return NULL;
938 }
939
940 hc = __get_uuid_cell(param->uuid);
941 if (!hc)
942 return NULL;
943 } else if (*param->name) {
944 if (param->dev) {
945 DMERR("Invalid ioctl structure: name %s, dev %llx",
946 param->name, (unsigned long long)param->dev);
947 return NULL;
948 }
949
950 hc = __get_name_cell(param->name);
951 if (!hc)
952 return NULL;
953 } else if (param->dev) {
954 hc = __get_dev_cell(param->dev);
955 if (!hc)
956 return NULL;
957 } else
958 return NULL;
959
960 /*
961 * Sneakily write in both the name and the uuid
962 * while we have the cell.
963 */
964 strscpy(param->name, hc->name, sizeof(param->name));
965 if (hc->uuid)
966 strscpy(param->uuid, hc->uuid, sizeof(param->uuid));
967 else
968 param->uuid[0] = '\0';
969
970 if (hc->new_map)
971 param->flags |= DM_INACTIVE_PRESENT_FLAG;
972 else
973 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
974
975 return hc;
976}
977
978static struct mapped_device *find_device(struct dm_ioctl *param)
979{
980 struct hash_cell *hc;
981 struct mapped_device *md = NULL;
982
983 down_read(&_hash_lock);
984 hc = __find_device_hash_cell(param);
985 if (hc)
986 md = hc->md;
987 up_read(&_hash_lock);
988
989 return md;
990}
991
992static int dev_remove(struct file *filp, struct dm_ioctl *param, size_t param_size)
993{
994 struct hash_cell *hc;
995 struct mapped_device *md;
996 int r;
997 struct dm_table *t;
998
999 down_write(&_hash_lock);
1000 hc = __find_device_hash_cell(param);
1001
1002 if (!hc) {
1003 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
1004 up_write(&_hash_lock);
1005 return -ENXIO;
1006 }
1007
1008 md = hc->md;
1009
1010 /*
1011 * Ensure the device is not open and nothing further can open it.
1012 */
1013 r = dm_lock_for_deletion(md, !!(param->flags & DM_DEFERRED_REMOVE), false);
1014 if (r) {
1015 if (r == -EBUSY && param->flags & DM_DEFERRED_REMOVE) {
1016 up_write(&_hash_lock);
1017 dm_put(md);
1018 return 0;
1019 }
1020 DMDEBUG_LIMIT("unable to remove open device %s", hc->name);
1021 up_write(&_hash_lock);
1022 dm_put(md);
1023 return r;
1024 }
1025
1026 t = __hash_remove(hc);
1027 up_write(&_hash_lock);
1028
1029 if (t) {
1030 dm_sync_table(md);
1031 dm_table_destroy(t);
1032 }
1033
1034 param->flags &= ~DM_DEFERRED_REMOVE;
1035
1036 dm_ima_measure_on_device_remove(md, false);
1037
1038 if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr, false))
1039 param->flags |= DM_UEVENT_GENERATED_FLAG;
1040
1041 dm_put(md);
1042 dm_destroy(md);
1043 return 0;
1044}
1045
1046/*
1047 * Check a string doesn't overrun the chunk of
1048 * memory we copied from userland.
1049 */
1050static int invalid_str(char *str, void *end)
1051{
1052 while ((void *) str < end)
1053 if (!*str++)
1054 return 0;
1055
1056 return -EINVAL;
1057}
1058
1059static int dev_rename(struct file *filp, struct dm_ioctl *param, size_t param_size)
1060{
1061 int r;
1062 char *new_data = (char *) param + param->data_start;
1063 struct mapped_device *md;
1064 unsigned int change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
1065
1066 if (new_data < param->data ||
1067 invalid_str(new_data, (void *) param + param_size) || !*new_data ||
1068 strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) {
1069 DMERR("Invalid new mapped device name or uuid string supplied.");
1070 return -EINVAL;
1071 }
1072
1073 if (!change_uuid) {
1074 r = check_name(new_data);
1075 if (r)
1076 return r;
1077 }
1078
1079 md = dm_hash_rename(param, new_data);
1080 if (IS_ERR(md))
1081 return PTR_ERR(md);
1082
1083 __dev_status(md, param);
1084 dm_put(md);
1085
1086 return 0;
1087}
1088
1089static int dev_set_geometry(struct file *filp, struct dm_ioctl *param, size_t param_size)
1090{
1091 int r = -EINVAL, x;
1092 struct mapped_device *md;
1093 struct hd_geometry geometry;
1094 unsigned long indata[4];
1095 char *geostr = (char *) param + param->data_start;
1096 char dummy;
1097
1098 md = find_device(param);
1099 if (!md)
1100 return -ENXIO;
1101
1102 if (geostr < param->data ||
1103 invalid_str(geostr, (void *) param + param_size)) {
1104 DMERR("Invalid geometry supplied.");
1105 goto out;
1106 }
1107
1108 x = sscanf(geostr, "%lu %lu %lu %lu%c", indata,
1109 indata + 1, indata + 2, indata + 3, &dummy);
1110
1111 if (x != 4) {
1112 DMERR("Unable to interpret geometry settings.");
1113 goto out;
1114 }
1115
1116 if (indata[0] > 65535 || indata[1] > 255 || indata[2] > 255) {
1117 DMERR("Geometry exceeds range limits.");
1118 goto out;
1119 }
1120
1121 geometry.cylinders = indata[0];
1122 geometry.heads = indata[1];
1123 geometry.sectors = indata[2];
1124 geometry.start = indata[3];
1125
1126 r = dm_set_geometry(md, &geometry);
1127
1128 param->data_size = 0;
1129
1130out:
1131 dm_put(md);
1132 return r;
1133}
1134
1135static int do_suspend(struct dm_ioctl *param)
1136{
1137 int r = 0;
1138 unsigned int suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
1139 struct mapped_device *md;
1140
1141 md = find_device(param);
1142 if (!md)
1143 return -ENXIO;
1144
1145 if (param->flags & DM_SKIP_LOCKFS_FLAG)
1146 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
1147 if (param->flags & DM_NOFLUSH_FLAG)
1148 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
1149
1150 if (!dm_suspended_md(md)) {
1151 r = dm_suspend(md, suspend_flags);
1152 if (r)
1153 goto out;
1154 }
1155
1156 __dev_status(md, param);
1157
1158out:
1159 dm_put(md);
1160
1161 return r;
1162}
1163
1164static int do_resume(struct dm_ioctl *param)
1165{
1166 int r = 0;
1167 unsigned int suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
1168 struct hash_cell *hc;
1169 struct mapped_device *md;
1170 struct dm_table *new_map, *old_map = NULL;
1171 bool need_resize_uevent = false;
1172
1173 down_write(&_hash_lock);
1174
1175 hc = __find_device_hash_cell(param);
1176 if (!hc) {
1177 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
1178 up_write(&_hash_lock);
1179 return -ENXIO;
1180 }
1181
1182 md = hc->md;
1183
1184 new_map = hc->new_map;
1185 hc->new_map = NULL;
1186 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1187
1188 up_write(&_hash_lock);
1189
1190 /* Do we need to load a new map ? */
1191 if (new_map) {
1192 sector_t old_size, new_size;
1193
1194 /* Suspend if it isn't already suspended */
1195 if (param->flags & DM_SKIP_LOCKFS_FLAG)
1196 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
1197 if (param->flags & DM_NOFLUSH_FLAG)
1198 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
1199 if (!dm_suspended_md(md)) {
1200 r = dm_suspend(md, suspend_flags);
1201 if (r) {
1202 down_write(&_hash_lock);
1203 hc = dm_get_mdptr(md);
1204 if (hc && !hc->new_map) {
1205 hc->new_map = new_map;
1206 new_map = NULL;
1207 } else {
1208 r = -ENXIO;
1209 }
1210 up_write(&_hash_lock);
1211 if (new_map) {
1212 dm_sync_table(md);
1213 dm_table_destroy(new_map);
1214 }
1215 dm_put(md);
1216 return r;
1217 }
1218 }
1219
1220 old_size = dm_get_size(md);
1221 old_map = dm_swap_table(md, new_map);
1222 if (IS_ERR(old_map)) {
1223 dm_sync_table(md);
1224 dm_table_destroy(new_map);
1225 dm_put(md);
1226 return PTR_ERR(old_map);
1227 }
1228 new_size = dm_get_size(md);
1229 if (old_size && new_size && old_size != new_size)
1230 need_resize_uevent = true;
1231
1232 if (dm_table_get_mode(new_map) & BLK_OPEN_WRITE)
1233 set_disk_ro(dm_disk(md), 0);
1234 else
1235 set_disk_ro(dm_disk(md), 1);
1236 }
1237
1238 if (dm_suspended_md(md)) {
1239 r = dm_resume(md);
1240 if (!r) {
1241 dm_ima_measure_on_device_resume(md, new_map ? true : false);
1242
1243 if (!dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr, need_resize_uevent))
1244 param->flags |= DM_UEVENT_GENERATED_FLAG;
1245 }
1246 }
1247
1248 /*
1249 * Since dm_swap_table synchronizes RCU, nobody should be in
1250 * read-side critical section already.
1251 */
1252 if (old_map)
1253 dm_table_destroy(old_map);
1254
1255 if (!r)
1256 __dev_status(md, param);
1257
1258 dm_put(md);
1259 return r;
1260}
1261
1262/*
1263 * Set or unset the suspension state of a device.
1264 * If the device already is in the requested state we just return its status.
1265 */
1266static int dev_suspend(struct file *filp, struct dm_ioctl *param, size_t param_size)
1267{
1268 if (param->flags & DM_SUSPEND_FLAG)
1269 return do_suspend(param);
1270
1271 return do_resume(param);
1272}
1273
1274/*
1275 * Copies device info back to user space, used by
1276 * the create and info ioctls.
1277 */
1278static int dev_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
1279{
1280 struct mapped_device *md;
1281
1282 md = find_device(param);
1283 if (!md)
1284 return -ENXIO;
1285
1286 __dev_status(md, param);
1287 dm_put(md);
1288
1289 return 0;
1290}
1291
1292/*
1293 * Build up the status struct for each target
1294 */
1295static void retrieve_status(struct dm_table *table,
1296 struct dm_ioctl *param, size_t param_size)
1297{
1298 unsigned int i, num_targets;
1299 struct dm_target_spec *spec;
1300 char *outbuf, *outptr;
1301 status_type_t type;
1302 size_t remaining, len, used = 0;
1303 unsigned int status_flags = 0;
1304
1305 outptr = outbuf = get_result_buffer(param, param_size, &len);
1306
1307 if (param->flags & DM_STATUS_TABLE_FLAG)
1308 type = STATUSTYPE_TABLE;
1309 else if (param->flags & DM_IMA_MEASUREMENT_FLAG)
1310 type = STATUSTYPE_IMA;
1311 else
1312 type = STATUSTYPE_INFO;
1313
1314 /* Get all the target info */
1315 num_targets = table->num_targets;
1316 for (i = 0; i < num_targets; i++) {
1317 struct dm_target *ti = dm_table_get_target(table, i);
1318 size_t l;
1319
1320 remaining = len - (outptr - outbuf);
1321 if (remaining <= sizeof(struct dm_target_spec)) {
1322 param->flags |= DM_BUFFER_FULL_FLAG;
1323 break;
1324 }
1325
1326 spec = (struct dm_target_spec *) outptr;
1327
1328 spec->status = 0;
1329 spec->sector_start = ti->begin;
1330 spec->length = ti->len;
1331 strscpy_pad(spec->target_type, ti->type->name,
1332 sizeof(spec->target_type));
1333
1334 outptr += sizeof(struct dm_target_spec);
1335 remaining = len - (outptr - outbuf);
1336 if (remaining <= 0) {
1337 param->flags |= DM_BUFFER_FULL_FLAG;
1338 break;
1339 }
1340
1341 /* Get the status/table string from the target driver */
1342 if (ti->type->status) {
1343 if (param->flags & DM_NOFLUSH_FLAG)
1344 status_flags |= DM_STATUS_NOFLUSH_FLAG;
1345 ti->type->status(ti, type, status_flags, outptr, remaining);
1346 } else
1347 outptr[0] = '\0';
1348
1349 l = strlen(outptr) + 1;
1350 if (l == remaining) {
1351 param->flags |= DM_BUFFER_FULL_FLAG;
1352 break;
1353 }
1354
1355 outptr += l;
1356 used = param->data_start + (outptr - outbuf);
1357
1358 outptr = align_ptr(outptr);
1359 if (!outptr || outptr > outbuf + len) {
1360 param->flags |= DM_BUFFER_FULL_FLAG;
1361 break;
1362 }
1363 spec->next = outptr - outbuf;
1364 }
1365
1366 if (used)
1367 param->data_size = used;
1368
1369 param->target_count = num_targets;
1370}
1371
1372/*
1373 * Wait for a device to report an event
1374 */
1375static int dev_wait(struct file *filp, struct dm_ioctl *param, size_t param_size)
1376{
1377 int r = 0;
1378 struct mapped_device *md;
1379 struct dm_table *table;
1380 int srcu_idx;
1381
1382 md = find_device(param);
1383 if (!md)
1384 return -ENXIO;
1385
1386 /*
1387 * Wait for a notification event
1388 */
1389 if (dm_wait_event(md, param->event_nr)) {
1390 r = -ERESTARTSYS;
1391 goto out;
1392 }
1393
1394 /*
1395 * The userland program is going to want to know what
1396 * changed to trigger the event, so we may as well tell
1397 * him and save an ioctl.
1398 */
1399 __dev_status(md, param);
1400
1401 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1402 if (table)
1403 retrieve_status(table, param, param_size);
1404 dm_put_live_table(md, srcu_idx);
1405
1406out:
1407 dm_put(md);
1408
1409 return r;
1410}
1411
1412/*
1413 * Remember the global event number and make it possible to poll
1414 * for further events.
1415 */
1416static int dev_arm_poll(struct file *filp, struct dm_ioctl *param, size_t param_size)
1417{
1418 struct dm_file *priv = filp->private_data;
1419
1420 priv->global_event_nr = atomic_read(&dm_global_event_nr);
1421
1422 return 0;
1423}
1424
1425static inline blk_mode_t get_mode(struct dm_ioctl *param)
1426{
1427 blk_mode_t mode = BLK_OPEN_READ | BLK_OPEN_WRITE;
1428
1429 if (param->flags & DM_READONLY_FLAG)
1430 mode = BLK_OPEN_READ;
1431
1432 return mode;
1433}
1434
1435static int next_target(struct dm_target_spec *last, uint32_t next, const char *end,
1436 struct dm_target_spec **spec, char **target_params)
1437{
1438 static_assert(__alignof__(struct dm_target_spec) <= 8,
1439 "struct dm_target_spec must not require more than 8-byte alignment");
1440
1441 /*
1442 * Number of bytes remaining, starting with last. This is always
1443 * sizeof(struct dm_target_spec) or more, as otherwise *last was
1444 * out of bounds already.
1445 */
1446 size_t remaining = end - (char *)last;
1447
1448 /*
1449 * There must be room for both the next target spec and the
1450 * NUL-terminator of the target itself.
1451 */
1452 if (remaining - sizeof(struct dm_target_spec) <= next) {
1453 DMERR("Target spec extends beyond end of parameters");
1454 return -EINVAL;
1455 }
1456
1457 if (next % __alignof__(struct dm_target_spec)) {
1458 DMERR("Next dm_target_spec (offset %u) is not %zu-byte aligned",
1459 next, __alignof__(struct dm_target_spec));
1460 return -EINVAL;
1461 }
1462
1463 *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
1464 *target_params = (char *) (*spec + 1);
1465
1466 return 0;
1467}
1468
1469static int populate_table(struct dm_table *table,
1470 struct dm_ioctl *param, size_t param_size)
1471{
1472 int r;
1473 unsigned int i = 0;
1474 struct dm_target_spec *spec = (struct dm_target_spec *) param;
1475 uint32_t next = param->data_start;
1476 const char *const end = (const char *) param + param_size;
1477 char *target_params;
1478 size_t min_size = sizeof(struct dm_ioctl);
1479
1480 if (!param->target_count) {
1481 DMERR("%s: no targets specified", __func__);
1482 return -EINVAL;
1483 }
1484
1485 for (i = 0; i < param->target_count; i++) {
1486 const char *nul_terminator;
1487
1488 if (next < min_size) {
1489 DMERR("%s: next target spec (offset %u) overlaps %s",
1490 __func__, next, i ? "previous target" : "'struct dm_ioctl'");
1491 return -EINVAL;
1492 }
1493
1494 r = next_target(spec, next, end, &spec, &target_params);
1495 if (r) {
1496 DMERR("unable to find target");
1497 return r;
1498 }
1499
1500 nul_terminator = memchr(target_params, 0, (size_t)(end - target_params));
1501 if (nul_terminator == NULL) {
1502 DMERR("%s: target parameters not NUL-terminated", __func__);
1503 return -EINVAL;
1504 }
1505
1506 /* Add 1 for NUL terminator */
1507 min_size = (size_t)(nul_terminator - (const char *)spec) + 1;
1508
1509 r = dm_table_add_target(table, spec->target_type,
1510 (sector_t) spec->sector_start,
1511 (sector_t) spec->length,
1512 target_params);
1513 if (r) {
1514 DMERR("error adding target to table");
1515 return r;
1516 }
1517
1518 next = spec->next;
1519 }
1520
1521 return dm_table_complete(table);
1522}
1523
1524static bool is_valid_type(enum dm_queue_mode cur, enum dm_queue_mode new)
1525{
1526 if (cur == new ||
1527 (cur == DM_TYPE_BIO_BASED && new == DM_TYPE_DAX_BIO_BASED))
1528 return true;
1529
1530 return false;
1531}
1532
1533static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_size)
1534{
1535 int r;
1536 struct hash_cell *hc;
1537 struct dm_table *t, *old_map = NULL;
1538 struct mapped_device *md;
1539 struct target_type *immutable_target_type;
1540
1541 md = find_device(param);
1542 if (!md)
1543 return -ENXIO;
1544
1545 r = dm_table_create(&t, get_mode(param), param->target_count, md);
1546 if (r)
1547 goto err;
1548
1549 /* Protect md->type and md->queue against concurrent table loads. */
1550 dm_lock_md_type(md);
1551 r = populate_table(t, param, param_size);
1552 if (r)
1553 goto err_unlock_md_type;
1554
1555 dm_ima_measure_on_table_load(t, STATUSTYPE_IMA);
1556
1557 immutable_target_type = dm_get_immutable_target_type(md);
1558 if (immutable_target_type &&
1559 (immutable_target_type != dm_table_get_immutable_target_type(t)) &&
1560 !dm_table_get_wildcard_target(t)) {
1561 DMERR("can't replace immutable target type %s",
1562 immutable_target_type->name);
1563 r = -EINVAL;
1564 goto err_unlock_md_type;
1565 }
1566
1567 if (dm_get_md_type(md) == DM_TYPE_NONE) {
1568 /* setup md->queue to reflect md's type (may block) */
1569 r = dm_setup_md_queue(md, t);
1570 if (r) {
1571 DMERR("unable to set up device queue for new table.");
1572 goto err_unlock_md_type;
1573 }
1574 } else if (!is_valid_type(dm_get_md_type(md), dm_table_get_type(t))) {
1575 DMERR("can't change device type (old=%u vs new=%u) after initial table load.",
1576 dm_get_md_type(md), dm_table_get_type(t));
1577 r = -EINVAL;
1578 goto err_unlock_md_type;
1579 }
1580
1581 dm_unlock_md_type(md);
1582
1583 /* stage inactive table */
1584 down_write(&_hash_lock);
1585 hc = dm_get_mdptr(md);
1586 if (!hc) {
1587 DMERR("device has been removed from the dev hash table.");
1588 up_write(&_hash_lock);
1589 r = -ENXIO;
1590 goto err_destroy_table;
1591 }
1592
1593 if (hc->new_map)
1594 old_map = hc->new_map;
1595 hc->new_map = t;
1596 up_write(&_hash_lock);
1597
1598 param->flags |= DM_INACTIVE_PRESENT_FLAG;
1599 __dev_status(md, param);
1600
1601 if (old_map) {
1602 dm_sync_table(md);
1603 dm_table_destroy(old_map);
1604 }
1605
1606 dm_put(md);
1607
1608 return 0;
1609
1610err_unlock_md_type:
1611 dm_unlock_md_type(md);
1612err_destroy_table:
1613 dm_table_destroy(t);
1614err:
1615 dm_put(md);
1616
1617 return r;
1618}
1619
1620static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_size)
1621{
1622 struct hash_cell *hc;
1623 struct mapped_device *md;
1624 struct dm_table *old_map = NULL;
1625 bool has_new_map = false;
1626
1627 down_write(&_hash_lock);
1628
1629 hc = __find_device_hash_cell(param);
1630 if (!hc) {
1631 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
1632 up_write(&_hash_lock);
1633 return -ENXIO;
1634 }
1635
1636 if (hc->new_map) {
1637 old_map = hc->new_map;
1638 hc->new_map = NULL;
1639 has_new_map = true;
1640 }
1641
1642 md = hc->md;
1643 up_write(&_hash_lock);
1644
1645 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1646 __dev_status(md, param);
1647
1648 if (old_map) {
1649 dm_sync_table(md);
1650 dm_table_destroy(old_map);
1651 }
1652 dm_ima_measure_on_table_clear(md, has_new_map);
1653 dm_put(md);
1654
1655 return 0;
1656}
1657
1658/*
1659 * Retrieves a list of devices used by a particular dm device.
1660 */
1661static void retrieve_deps(struct dm_table *table,
1662 struct dm_ioctl *param, size_t param_size)
1663{
1664 unsigned int count = 0;
1665 struct list_head *tmp;
1666 size_t len, needed;
1667 struct dm_dev_internal *dd;
1668 struct dm_target_deps *deps;
1669
1670 deps = get_result_buffer(param, param_size, &len);
1671
1672 /*
1673 * Count the devices.
1674 */
1675 list_for_each(tmp, dm_table_get_devices(table))
1676 count++;
1677
1678 /*
1679 * Check we have enough space.
1680 */
1681 needed = struct_size(deps, dev, count);
1682 if (len < needed) {
1683 param->flags |= DM_BUFFER_FULL_FLAG;
1684 return;
1685 }
1686
1687 /*
1688 * Fill in the devices.
1689 */
1690 deps->count = count;
1691 count = 0;
1692 list_for_each_entry(dd, dm_table_get_devices(table), list)
1693 deps->dev[count++] = huge_encode_dev(dd->dm_dev->bdev->bd_dev);
1694
1695 param->data_size = param->data_start + needed;
1696}
1697
1698static int table_deps(struct file *filp, struct dm_ioctl *param, size_t param_size)
1699{
1700 struct mapped_device *md;
1701 struct dm_table *table;
1702 int srcu_idx;
1703
1704 md = find_device(param);
1705 if (!md)
1706 return -ENXIO;
1707
1708 __dev_status(md, param);
1709
1710 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1711 if (table)
1712 retrieve_deps(table, param, param_size);
1713 dm_put_live_table(md, srcu_idx);
1714
1715 dm_put(md);
1716
1717 return 0;
1718}
1719
1720/*
1721 * Return the status of a device as a text string for each
1722 * target.
1723 */
1724static int table_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
1725{
1726 struct mapped_device *md;
1727 struct dm_table *table;
1728 int srcu_idx;
1729
1730 md = find_device(param);
1731 if (!md)
1732 return -ENXIO;
1733
1734 __dev_status(md, param);
1735
1736 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1737 if (table)
1738 retrieve_status(table, param, param_size);
1739 dm_put_live_table(md, srcu_idx);
1740
1741 dm_put(md);
1742
1743 return 0;
1744}
1745
1746/*
1747 * Process device-mapper dependent messages. Messages prefixed with '@'
1748 * are processed by the DM core. All others are delivered to the target.
1749 * Returns a number <= 1 if message was processed by device mapper.
1750 * Returns 2 if message should be delivered to the target.
1751 */
1752static int message_for_md(struct mapped_device *md, unsigned int argc, char **argv,
1753 char *result, unsigned int maxlen)
1754{
1755 int r;
1756
1757 if (**argv != '@')
1758 return 2; /* no '@' prefix, deliver to target */
1759
1760 if (!strcasecmp(argv[0], "@cancel_deferred_remove")) {
1761 if (argc != 1) {
1762 DMERR("Invalid arguments for @cancel_deferred_remove");
1763 return -EINVAL;
1764 }
1765 return dm_cancel_deferred_remove(md);
1766 }
1767
1768 r = dm_stats_message(md, argc, argv, result, maxlen);
1769 if (r < 2)
1770 return r;
1771
1772 DMERR("Unsupported message sent to DM core: %s", argv[0]);
1773 return -EINVAL;
1774}
1775
1776/*
1777 * Pass a message to the target that's at the supplied device offset.
1778 */
1779static int target_message(struct file *filp, struct dm_ioctl *param, size_t param_size)
1780{
1781 int r, argc;
1782 char **argv;
1783 struct mapped_device *md;
1784 struct dm_table *table;
1785 struct dm_target *ti;
1786 struct dm_target_msg *tmsg = (void *) param + param->data_start;
1787 size_t maxlen;
1788 char *result = get_result_buffer(param, param_size, &maxlen);
1789 int srcu_idx;
1790
1791 md = find_device(param);
1792 if (!md)
1793 return -ENXIO;
1794
1795 if (tmsg < (struct dm_target_msg *) param->data ||
1796 invalid_str(tmsg->message, (void *) param + param_size)) {
1797 DMERR("Invalid target message parameters.");
1798 r = -EINVAL;
1799 goto out;
1800 }
1801
1802 r = dm_split_args(&argc, &argv, tmsg->message);
1803 if (r) {
1804 DMERR("Failed to split target message parameters");
1805 goto out;
1806 }
1807
1808 if (!argc) {
1809 DMERR("Empty message received.");
1810 r = -EINVAL;
1811 goto out_argv;
1812 }
1813
1814 r = message_for_md(md, argc, argv, result, maxlen);
1815 if (r <= 1)
1816 goto out_argv;
1817
1818 table = dm_get_live_table(md, &srcu_idx);
1819 if (!table)
1820 goto out_table;
1821
1822 if (dm_deleting_md(md)) {
1823 r = -ENXIO;
1824 goto out_table;
1825 }
1826
1827 ti = dm_table_find_target(table, tmsg->sector);
1828 if (!ti) {
1829 DMERR("Target message sector outside device.");
1830 r = -EINVAL;
1831 } else if (ti->type->message)
1832 r = ti->type->message(ti, argc, argv, result, maxlen);
1833 else {
1834 DMERR("Target type does not support messages");
1835 r = -EINVAL;
1836 }
1837
1838 out_table:
1839 dm_put_live_table(md, srcu_idx);
1840 out_argv:
1841 kfree(argv);
1842 out:
1843 if (r >= 0)
1844 __dev_status(md, param);
1845
1846 if (r == 1) {
1847 param->flags |= DM_DATA_OUT_FLAG;
1848 if (dm_message_test_buffer_overflow(result, maxlen))
1849 param->flags |= DM_BUFFER_FULL_FLAG;
1850 else
1851 param->data_size = param->data_start + strlen(result) + 1;
1852 r = 0;
1853 }
1854
1855 dm_put(md);
1856 return r;
1857}
1858
1859/*
1860 * The ioctl parameter block consists of two parts, a dm_ioctl struct
1861 * followed by a data buffer. This flag is set if the second part,
1862 * which has a variable size, is not used by the function processing
1863 * the ioctl.
1864 */
1865#define IOCTL_FLAGS_NO_PARAMS 1
1866#define IOCTL_FLAGS_ISSUE_GLOBAL_EVENT 2
1867
1868/*
1869 *---------------------------------------------------------------
1870 * Implementation of open/close/ioctl on the special char device.
1871 *---------------------------------------------------------------
1872 */
1873static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
1874{
1875 static const struct {
1876 int cmd;
1877 int flags;
1878 ioctl_fn fn;
1879 } _ioctls[] = {
1880 {DM_VERSION_CMD, 0, NULL}, /* version is dealt with elsewhere */
1881 {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, remove_all},
1882 {DM_LIST_DEVICES_CMD, 0, list_devices},
1883
1884 {DM_DEV_CREATE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_create},
1885 {DM_DEV_REMOVE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_remove},
1886 {DM_DEV_RENAME_CMD, IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_rename},
1887 {DM_DEV_SUSPEND_CMD, IOCTL_FLAGS_NO_PARAMS, dev_suspend},
1888 {DM_DEV_STATUS_CMD, IOCTL_FLAGS_NO_PARAMS, dev_status},
1889 {DM_DEV_WAIT_CMD, 0, dev_wait},
1890
1891 {DM_TABLE_LOAD_CMD, 0, table_load},
1892 {DM_TABLE_CLEAR_CMD, IOCTL_FLAGS_NO_PARAMS, table_clear},
1893 {DM_TABLE_DEPS_CMD, 0, table_deps},
1894 {DM_TABLE_STATUS_CMD, 0, table_status},
1895
1896 {DM_LIST_VERSIONS_CMD, 0, list_versions},
1897
1898 {DM_TARGET_MSG_CMD, 0, target_message},
1899 {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry},
1900 {DM_DEV_ARM_POLL_CMD, IOCTL_FLAGS_NO_PARAMS, dev_arm_poll},
1901 {DM_GET_TARGET_VERSION_CMD, 0, get_target_version},
1902 {DM_MPATH_PROBE_PATHS_CMD, 0, NULL}, /* block device ioctl */
1903 };
1904
1905 if (unlikely(cmd >= ARRAY_SIZE(_ioctls)))
1906 return NULL;
1907
1908 cmd = array_index_nospec(cmd, ARRAY_SIZE(_ioctls));
1909 *ioctl_flags = _ioctls[cmd].flags;
1910 return _ioctls[cmd].fn;
1911}
1912
1913/*
1914 * As well as checking the version compatibility this always
1915 * copies the kernel interface version out.
1916 */
1917static int check_version(unsigned int cmd, struct dm_ioctl __user *user,
1918 struct dm_ioctl *kernel_params)
1919{
1920 int r = 0;
1921
1922 /* Make certain version is first member of dm_ioctl struct */
1923 BUILD_BUG_ON(offsetof(struct dm_ioctl, version) != 0);
1924
1925 if (copy_from_user(kernel_params->version, user->version, sizeof(kernel_params->version)))
1926 return -EFAULT;
1927
1928 if ((kernel_params->version[0] != DM_VERSION_MAJOR) ||
1929 (kernel_params->version[1] > DM_VERSION_MINOR)) {
1930 DMERR_LIMIT("ioctl interface mismatch: kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1931 DM_VERSION_MAJOR, DM_VERSION_MINOR,
1932 DM_VERSION_PATCHLEVEL,
1933 kernel_params->version[0],
1934 kernel_params->version[1],
1935 kernel_params->version[2],
1936 cmd);
1937 r = -EINVAL;
1938 }
1939
1940 /*
1941 * Fill in the kernel version.
1942 */
1943 kernel_params->version[0] = DM_VERSION_MAJOR;
1944 kernel_params->version[1] = DM_VERSION_MINOR;
1945 kernel_params->version[2] = DM_VERSION_PATCHLEVEL;
1946 if (copy_to_user(user->version, kernel_params->version, sizeof(kernel_params->version)))
1947 return -EFAULT;
1948
1949 return r;
1950}
1951
1952#define DM_PARAMS_MALLOC 0x0001 /* Params allocated with kvmalloc() */
1953#define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */
1954
1955static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags)
1956{
1957 if (param_flags & DM_WIPE_BUFFER)
1958 memset(param, 0, param_size);
1959
1960 if (param_flags & DM_PARAMS_MALLOC)
1961 kvfree(param);
1962}
1963
1964static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel,
1965 int ioctl_flags, struct dm_ioctl **param, int *param_flags)
1966{
1967 struct dm_ioctl *dmi;
1968 int secure_data;
1969 const size_t minimum_data_size = offsetof(struct dm_ioctl, data);
1970
1971 /* check_version() already copied version from userspace, avoid TOCTOU */
1972 if (copy_from_user((char *)param_kernel + sizeof(param_kernel->version),
1973 (char __user *)user + sizeof(param_kernel->version),
1974 minimum_data_size - sizeof(param_kernel->version)))
1975 return -EFAULT;
1976
1977 if (unlikely(param_kernel->data_size < minimum_data_size) ||
1978 unlikely(param_kernel->data_size > DM_MAX_TARGETS * DM_MAX_TARGET_PARAMS)) {
1979 DMERR_LIMIT("Invalid data size in the ioctl structure: %u",
1980 param_kernel->data_size);
1981 return -EINVAL;
1982 }
1983
1984 secure_data = param_kernel->flags & DM_SECURE_DATA_FLAG;
1985
1986 *param_flags = secure_data ? DM_WIPE_BUFFER : 0;
1987
1988 if (ioctl_flags & IOCTL_FLAGS_NO_PARAMS) {
1989 dmi = param_kernel;
1990 dmi->data_size = minimum_data_size;
1991 goto data_copied;
1992 }
1993
1994 /*
1995 * Use __GFP_HIGH to avoid low memory issues when a device is
1996 * suspended and the ioctl is needed to resume it.
1997 * Use kmalloc() rather than vmalloc() when we can.
1998 */
1999 dmi = NULL;
2000 dmi = kvmalloc(param_kernel->data_size, GFP_NOIO | __GFP_HIGH);
2001
2002 if (!dmi) {
2003 if (secure_data && clear_user(user, param_kernel->data_size))
2004 return -EFAULT;
2005 return -ENOMEM;
2006 }
2007
2008 *param_flags |= DM_PARAMS_MALLOC;
2009
2010 /* Copy from param_kernel (which was already copied from user) */
2011 memcpy(dmi, param_kernel, minimum_data_size);
2012
2013 if (copy_from_user(&dmi->data, (char __user *)user + minimum_data_size,
2014 param_kernel->data_size - minimum_data_size))
2015 goto bad;
2016data_copied:
2017 /* Wipe the user buffer so we do not return it to userspace */
2018 if (secure_data && clear_user(user, param_kernel->data_size))
2019 goto bad;
2020
2021 *param = dmi;
2022 return 0;
2023
2024bad:
2025 free_params(dmi, param_kernel->data_size, *param_flags);
2026
2027 return -EFAULT;
2028}
2029
2030static int validate_params(uint cmd, struct dm_ioctl *param)
2031{
2032 /* Always clear this flag */
2033 param->flags &= ~DM_BUFFER_FULL_FLAG;
2034 param->flags &= ~DM_UEVENT_GENERATED_FLAG;
2035 param->flags &= ~DM_SECURE_DATA_FLAG;
2036 param->flags &= ~DM_DATA_OUT_FLAG;
2037
2038 /* Ignores parameters */
2039 if (cmd == DM_REMOVE_ALL_CMD ||
2040 cmd == DM_LIST_DEVICES_CMD ||
2041 cmd == DM_LIST_VERSIONS_CMD)
2042 return 0;
2043
2044 if (cmd == DM_DEV_CREATE_CMD) {
2045 if (!*param->name) {
2046 DMERR("name not supplied when creating device");
2047 return -EINVAL;
2048 }
2049 } else if (*param->uuid && *param->name) {
2050 DMERR("only supply one of name or uuid, cmd(%u)", cmd);
2051 return -EINVAL;
2052 }
2053
2054 /* Ensure strings are terminated */
2055 param->name[DM_NAME_LEN - 1] = '\0';
2056 param->uuid[DM_UUID_LEN - 1] = '\0';
2057
2058 return 0;
2059}
2060
2061static int ctl_ioctl(struct file *file, uint command, struct dm_ioctl __user *user)
2062{
2063 int r = 0;
2064 int ioctl_flags;
2065 int param_flags;
2066 unsigned int cmd;
2067 struct dm_ioctl *param;
2068 ioctl_fn fn = NULL;
2069 size_t input_param_size;
2070 struct dm_ioctl param_kernel;
2071
2072 /* only root can play with this */
2073 if (!capable(CAP_SYS_ADMIN))
2074 return -EACCES;
2075
2076 if (_IOC_TYPE(command) != DM_IOCTL)
2077 return -ENOTTY;
2078
2079 cmd = _IOC_NR(command);
2080
2081 /*
2082 * Check the interface version passed in. This also
2083 * writes out the kernel's interface version.
2084 */
2085 r = check_version(cmd, user, ¶m_kernel);
2086 if (r)
2087 return r;
2088
2089 /*
2090 * Nothing more to do for the version command.
2091 */
2092 if (cmd == DM_VERSION_CMD)
2093 return 0;
2094
2095 fn = lookup_ioctl(cmd, &ioctl_flags);
2096 if (!fn) {
2097 DMERR("dm_ctl_ioctl: unknown command 0x%x", command);
2098 return -ENOTTY;
2099 }
2100
2101 /*
2102 * Copy the parameters into kernel space.
2103 */
2104 r = copy_params(user, ¶m_kernel, ioctl_flags, ¶m, ¶m_flags);
2105
2106 if (r)
2107 return r;
2108
2109 input_param_size = param->data_size;
2110 r = validate_params(cmd, param);
2111 if (r)
2112 goto out;
2113
2114 param->data_size = offsetof(struct dm_ioctl, data);
2115 r = fn(file, param, input_param_size);
2116
2117 if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) &&
2118 unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS))
2119 DMERR("ioctl %d tried to output some data but has IOCTL_FLAGS_NO_PARAMS set", cmd);
2120
2121 if (!r && ioctl_flags & IOCTL_FLAGS_ISSUE_GLOBAL_EVENT)
2122 dm_issue_global_event();
2123
2124 /*
2125 * Copy the results back to userland.
2126 */
2127 if (!r && copy_to_user(user, param, param->data_size))
2128 r = -EFAULT;
2129
2130out:
2131 free_params(param, input_param_size, param_flags);
2132 return r;
2133}
2134
2135static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
2136{
2137 return (long)ctl_ioctl(file, command, (struct dm_ioctl __user *)u);
2138}
2139
2140#ifdef CONFIG_COMPAT
2141static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
2142{
2143 return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
2144}
2145#else
2146#define dm_compat_ctl_ioctl NULL
2147#endif
2148
2149static int dm_open(struct inode *inode, struct file *filp)
2150{
2151 int r;
2152 struct dm_file *priv;
2153
2154 r = nonseekable_open(inode, filp);
2155 if (unlikely(r))
2156 return r;
2157
2158 priv = filp->private_data = kmalloc_obj(struct dm_file);
2159 if (!priv)
2160 return -ENOMEM;
2161
2162 priv->global_event_nr = atomic_read(&dm_global_event_nr);
2163
2164 return 0;
2165}
2166
2167static int dm_release(struct inode *inode, struct file *filp)
2168{
2169 kfree(filp->private_data);
2170 return 0;
2171}
2172
2173static __poll_t dm_poll(struct file *filp, poll_table *wait)
2174{
2175 struct dm_file *priv = filp->private_data;
2176 __poll_t mask = 0;
2177
2178 poll_wait(filp, &dm_global_eventq, wait);
2179
2180 if ((int)(atomic_read(&dm_global_event_nr) - priv->global_event_nr) > 0)
2181 mask |= EPOLLIN;
2182
2183 return mask;
2184}
2185
2186static const struct file_operations _ctl_fops = {
2187 .open = dm_open,
2188 .release = dm_release,
2189 .poll = dm_poll,
2190 .unlocked_ioctl = dm_ctl_ioctl,
2191 .compat_ioctl = dm_compat_ctl_ioctl,
2192 .owner = THIS_MODULE,
2193 .llseek = noop_llseek,
2194};
2195
2196static struct miscdevice _dm_misc = {
2197 .minor = MAPPER_CTRL_MINOR,
2198 .name = DM_NAME,
2199 .nodename = DM_DIR "/" DM_CONTROL_NODE,
2200 .fops = &_ctl_fops
2201};
2202
2203MODULE_ALIAS_MISCDEV(MAPPER_CTRL_MINOR);
2204MODULE_ALIAS("devname:" DM_DIR "/" DM_CONTROL_NODE);
2205
2206/*
2207 * Create misc character device and link to DM_DIR/control.
2208 */
2209int __init dm_interface_init(void)
2210{
2211 int r;
2212
2213 r = misc_register(&_dm_misc);
2214 if (r) {
2215 DMERR("misc_register failed for control device");
2216 return r;
2217 }
2218
2219 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
2220 DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
2221 DM_DRIVER_EMAIL);
2222 return 0;
2223}
2224
2225void dm_interface_exit(void)
2226{
2227 misc_deregister(&_dm_misc);
2228 dm_hash_exit();
2229}
2230
2231/**
2232 * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
2233 * @md: Pointer to mapped_device
2234 * @name: Buffer (size DM_NAME_LEN) for name
2235 * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
2236 */
2237int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
2238{
2239 int r = 0;
2240 struct hash_cell *hc;
2241
2242 if (!md)
2243 return -ENXIO;
2244
2245 mutex_lock(&dm_hash_cells_mutex);
2246 hc = dm_get_mdptr(md);
2247 if (!hc) {
2248 r = -ENXIO;
2249 goto out;
2250 }
2251
2252 if (name)
2253 strcpy(name, hc->name);
2254 if (uuid)
2255 strcpy(uuid, hc->uuid ? : "");
2256
2257out:
2258 mutex_unlock(&dm_hash_cells_mutex);
2259
2260 return r;
2261}
2262EXPORT_SYMBOL_GPL(dm_copy_name_and_uuid);
2263
2264/**
2265 * dm_early_create - create a mapped device in early boot.
2266 *
2267 * @dmi: Contains main information of the device mapping to be created.
2268 * @spec_array: array of pointers to struct dm_target_spec. Describes the
2269 * mapping table of the device.
2270 * @target_params_array: array of strings with the parameters to a specific
2271 * target.
2272 *
2273 * Instead of having the struct dm_target_spec and the parameters for every
2274 * target embedded at the end of struct dm_ioctl (as performed in a normal
2275 * ioctl), pass them as arguments, so the caller doesn't need to serialize them.
2276 * The size of the spec_array and target_params_array is given by
2277 * @dmi->target_count.
2278 * This function is supposed to be called in early boot, so locking mechanisms
2279 * to protect against concurrent loads are not required.
2280 */
2281int __init dm_early_create(struct dm_ioctl *dmi,
2282 struct dm_target_spec **spec_array,
2283 char **target_params_array)
2284{
2285 int r, m = DM_ANY_MINOR;
2286 struct dm_table *t, *old_map;
2287 struct mapped_device *md;
2288 unsigned int i;
2289
2290 if (!dmi->target_count)
2291 return -EINVAL;
2292
2293 r = check_name(dmi->name);
2294 if (r)
2295 return r;
2296
2297 if (dmi->flags & DM_PERSISTENT_DEV_FLAG)
2298 m = MINOR(huge_decode_dev(dmi->dev));
2299
2300 /* alloc dm device */
2301 r = dm_create(m, &md);
2302 if (r)
2303 return r;
2304
2305 /* hash insert */
2306 r = dm_hash_insert(dmi->name, *dmi->uuid ? dmi->uuid : NULL, md);
2307 if (r)
2308 goto err_destroy_dm;
2309
2310 /* alloc table */
2311 r = dm_table_create(&t, get_mode(dmi), dmi->target_count, md);
2312 if (r)
2313 goto err_hash_remove;
2314
2315 /* add targets */
2316 for (i = 0; i < dmi->target_count; i++) {
2317 r = dm_table_add_target(t, spec_array[i]->target_type,
2318 (sector_t) spec_array[i]->sector_start,
2319 (sector_t) spec_array[i]->length,
2320 target_params_array[i]);
2321 if (r) {
2322 DMERR("error adding target to table");
2323 goto err_destroy_table;
2324 }
2325 }
2326
2327 /* finish table */
2328 r = dm_table_complete(t);
2329 if (r)
2330 goto err_destroy_table;
2331
2332 /* setup md->queue to reflect md's type (may block) */
2333 r = dm_setup_md_queue(md, t);
2334 if (r) {
2335 DMERR("unable to set up device queue for new table.");
2336 goto err_destroy_table;
2337 }
2338
2339 /* Set new map */
2340 dm_suspend(md, 0);
2341 old_map = dm_swap_table(md, t);
2342 if (IS_ERR(old_map)) {
2343 r = PTR_ERR(old_map);
2344 goto err_destroy_table;
2345 }
2346 set_disk_ro(dm_disk(md), !!(dmi->flags & DM_READONLY_FLAG));
2347
2348 /* resume device */
2349 r = dm_resume(md);
2350 if (r)
2351 goto err_destroy_table;
2352
2353 DMINFO("%s (%s) is ready", md->disk->disk_name, dmi->name);
2354 dm_put(md);
2355 return 0;
2356
2357err_destroy_table:
2358 dm_table_destroy(t);
2359err_hash_remove:
2360 down_write(&_hash_lock);
2361 (void) __hash_remove(__get_name_cell(dmi->name));
2362 up_write(&_hash_lock);
2363 /* release reference from __get_name_cell */
2364 dm_put(md);
2365err_destroy_dm:
2366 dm_put(md);
2367 dm_destroy(md);
2368 return r;
2369}