Line data Source code
1 : /*
2 : * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
3 : * Copyright (C) 2004 - 2006 Red Hat, Inc. All rights reserved.
4 : *
5 : * This file is released under the GPL.
6 : */
7 :
8 : #include "dm-core.h"
9 :
10 : #include <linux/module.h>
11 : #include <linux/vmalloc.h>
12 : #include <linux/miscdevice.h>
13 : #include <linux/sched/mm.h>
14 : #include <linux/init.h>
15 : #include <linux/wait.h>
16 : #include <linux/slab.h>
17 : #include <linux/dm-ioctl.h>
18 : #include <linux/hdreg.h>
19 : #include <linux/compat.h>
20 :
21 : #include <linux/uaccess.h>
22 :
23 : #define DM_MSG_PREFIX "ioctl"
24 : #define DM_DRIVER_EMAIL "dm-devel@redhat.com"
25 :
26 : struct dm_file {
27 : /*
28 : * poll will wait until the global event number is greater than
29 : * this value.
30 : */
31 : volatile unsigned global_event_nr;
32 : };
33 :
34 : /*-----------------------------------------------------------------
35 : * The ioctl interface needs to be able to look up devices by
36 : * name or uuid.
37 : *---------------------------------------------------------------*/
38 : struct hash_cell {
39 : struct list_head name_list;
40 : struct list_head uuid_list;
41 :
42 : char *name;
43 : char *uuid;
44 : struct mapped_device *md;
45 : struct dm_table *new_map;
46 : };
47 :
48 : struct vers_iter {
49 : size_t param_size;
50 : struct dm_target_versions *vers, *old_vers;
51 : char *end;
52 : uint32_t flags;
53 : };
54 :
55 :
56 : #define NUM_BUCKETS 64
57 : #define MASK_BUCKETS (NUM_BUCKETS - 1)
58 : static struct list_head _name_buckets[NUM_BUCKETS];
59 : static struct list_head _uuid_buckets[NUM_BUCKETS];
60 :
61 : static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred);
62 :
63 : /*
64 : * Guards access to both hash tables.
65 : */
66 : static DECLARE_RWSEM(_hash_lock);
67 :
68 : /*
69 : * Protects use of mdptr to obtain hash cell name and uuid from mapped device.
70 : */
71 : static DEFINE_MUTEX(dm_hash_cells_mutex);
72 :
73 1 : static void init_buckets(struct list_head *buckets)
74 : {
75 1 : unsigned int i;
76 :
77 129 : for (i = 0; i < NUM_BUCKETS; i++)
78 128 : INIT_LIST_HEAD(buckets + i);
79 : }
80 :
81 1 : static int dm_hash_init(void)
82 : {
83 1 : init_buckets(_name_buckets);
84 65 : init_buckets(_uuid_buckets);
85 1 : return 0;
86 : }
87 :
88 0 : static void dm_hash_exit(void)
89 : {
90 0 : dm_hash_remove_all(false, false, false);
91 : }
92 :
93 : /*-----------------------------------------------------------------
94 : * Hash function:
95 : * We're not really concerned with the str hash function being
96 : * fast since it's only used by the ioctl interface.
97 : *---------------------------------------------------------------*/
98 0 : static unsigned int hash_str(const char *str)
99 : {
100 0 : const unsigned int hash_mult = 2654435387U;
101 0 : unsigned int h = 0;
102 :
103 0 : while (*str)
104 0 : h = (h + (unsigned int) *str++) * hash_mult;
105 :
106 0 : return h & MASK_BUCKETS;
107 : }
108 :
109 : /*-----------------------------------------------------------------
110 : * Code for looking up a device by name
111 : *---------------------------------------------------------------*/
112 0 : static struct hash_cell *__get_name_cell(const char *str)
113 : {
114 0 : struct hash_cell *hc;
115 0 : unsigned int h = hash_str(str);
116 :
117 0 : list_for_each_entry (hc, _name_buckets + h, name_list)
118 0 : if (!strcmp(hc->name, str)) {
119 0 : dm_get(hc->md);
120 0 : return hc;
121 : }
122 :
123 : return NULL;
124 : }
125 :
126 0 : static struct hash_cell *__get_uuid_cell(const char *str)
127 : {
128 0 : struct hash_cell *hc;
129 0 : unsigned int h = hash_str(str);
130 :
131 0 : list_for_each_entry (hc, _uuid_buckets + h, uuid_list)
132 0 : if (!strcmp(hc->uuid, str)) {
133 0 : dm_get(hc->md);
134 0 : return hc;
135 : }
136 :
137 : return NULL;
138 : }
139 :
140 0 : static struct hash_cell *__get_dev_cell(uint64_t dev)
141 : {
142 0 : struct mapped_device *md;
143 0 : struct hash_cell *hc;
144 :
145 0 : md = dm_get_md(huge_decode_dev(dev));
146 0 : if (!md)
147 : return NULL;
148 :
149 0 : hc = dm_get_mdptr(md);
150 0 : if (!hc) {
151 0 : dm_put(md);
152 0 : return NULL;
153 : }
154 :
155 : return hc;
156 : }
157 :
158 : /*-----------------------------------------------------------------
159 : * Inserting, removing and renaming a device.
160 : *---------------------------------------------------------------*/
161 0 : static struct hash_cell *alloc_cell(const char *name, const char *uuid,
162 : struct mapped_device *md)
163 : {
164 0 : struct hash_cell *hc;
165 :
166 0 : hc = kmalloc(sizeof(*hc), GFP_KERNEL);
167 0 : if (!hc)
168 : return NULL;
169 :
170 0 : hc->name = kstrdup(name, GFP_KERNEL);
171 0 : if (!hc->name) {
172 0 : kfree(hc);
173 0 : return NULL;
174 : }
175 :
176 0 : if (!uuid)
177 0 : hc->uuid = NULL;
178 :
179 : else {
180 0 : hc->uuid = kstrdup(uuid, GFP_KERNEL);
181 0 : if (!hc->uuid) {
182 0 : kfree(hc->name);
183 0 : kfree(hc);
184 0 : return NULL;
185 : }
186 : }
187 :
188 0 : INIT_LIST_HEAD(&hc->name_list);
189 0 : INIT_LIST_HEAD(&hc->uuid_list);
190 0 : hc->md = md;
191 0 : hc->new_map = NULL;
192 0 : return hc;
193 : }
194 :
195 0 : static void free_cell(struct hash_cell *hc)
196 : {
197 0 : if (hc) {
198 0 : kfree(hc->name);
199 0 : kfree(hc->uuid);
200 0 : kfree(hc);
201 : }
202 0 : }
203 :
204 : /*
205 : * The kdev_t and uuid of a device can never change once it is
206 : * initially inserted.
207 : */
208 0 : static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
209 : {
210 0 : struct hash_cell *cell, *hc;
211 :
212 : /*
213 : * Allocate the new cells.
214 : */
215 0 : cell = alloc_cell(name, uuid, md);
216 0 : if (!cell)
217 : return -ENOMEM;
218 :
219 : /*
220 : * Insert the cell into both hash tables.
221 : */
222 0 : down_write(&_hash_lock);
223 0 : hc = __get_name_cell(name);
224 0 : if (hc) {
225 0 : dm_put(hc->md);
226 0 : goto bad;
227 : }
228 :
229 0 : list_add(&cell->name_list, _name_buckets + hash_str(name));
230 :
231 0 : if (uuid) {
232 0 : hc = __get_uuid_cell(uuid);
233 0 : if (hc) {
234 0 : list_del(&cell->name_list);
235 0 : dm_put(hc->md);
236 0 : goto bad;
237 : }
238 0 : list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
239 : }
240 0 : dm_get(md);
241 0 : mutex_lock(&dm_hash_cells_mutex);
242 0 : dm_set_mdptr(md, cell);
243 0 : mutex_unlock(&dm_hash_cells_mutex);
244 0 : up_write(&_hash_lock);
245 :
246 0 : return 0;
247 :
248 0 : bad:
249 0 : up_write(&_hash_lock);
250 0 : free_cell(cell);
251 0 : return -EBUSY;
252 : }
253 :
254 0 : static struct dm_table *__hash_remove(struct hash_cell *hc)
255 : {
256 0 : struct dm_table *table;
257 0 : int srcu_idx;
258 :
259 : /* remove from the dev hash */
260 0 : list_del(&hc->uuid_list);
261 0 : list_del(&hc->name_list);
262 0 : mutex_lock(&dm_hash_cells_mutex);
263 0 : dm_set_mdptr(hc->md, NULL);
264 0 : mutex_unlock(&dm_hash_cells_mutex);
265 :
266 0 : table = dm_get_live_table(hc->md, &srcu_idx);
267 0 : if (table)
268 0 : dm_table_event(table);
269 0 : dm_put_live_table(hc->md, srcu_idx);
270 :
271 0 : table = NULL;
272 0 : if (hc->new_map)
273 0 : table = hc->new_map;
274 0 : dm_put(hc->md);
275 0 : free_cell(hc);
276 :
277 0 : return table;
278 : }
279 :
280 0 : static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred)
281 : {
282 0 : int i, dev_skipped;
283 0 : struct hash_cell *hc;
284 0 : struct mapped_device *md;
285 0 : struct dm_table *t;
286 :
287 0 : retry:
288 0 : dev_skipped = 0;
289 :
290 0 : down_write(&_hash_lock);
291 :
292 0 : for (i = 0; i < NUM_BUCKETS; i++) {
293 0 : list_for_each_entry(hc, _name_buckets + i, name_list) {
294 0 : md = hc->md;
295 0 : dm_get(md);
296 :
297 0 : if (keep_open_devices &&
298 0 : dm_lock_for_deletion(md, mark_deferred, only_deferred)) {
299 0 : dm_put(md);
300 0 : dev_skipped++;
301 0 : continue;
302 : }
303 :
304 0 : t = __hash_remove(hc);
305 :
306 0 : up_write(&_hash_lock);
307 :
308 0 : if (t) {
309 0 : dm_sync_table(md);
310 0 : dm_table_destroy(t);
311 : }
312 0 : dm_put(md);
313 0 : if (likely(keep_open_devices))
314 0 : dm_destroy(md);
315 : else
316 0 : dm_destroy_immediate(md);
317 :
318 : /*
319 : * Some mapped devices may be using other mapped
320 : * devices, so repeat until we make no further
321 : * progress. If a new mapped device is created
322 : * here it will also get removed.
323 : */
324 0 : goto retry;
325 : }
326 : }
327 :
328 0 : up_write(&_hash_lock);
329 :
330 0 : if (dev_skipped)
331 0 : DMWARN("remove_all left %d open device(s)", dev_skipped);
332 0 : }
333 :
334 : /*
335 : * Set the uuid of a hash_cell that isn't already set.
336 : */
337 0 : static void __set_cell_uuid(struct hash_cell *hc, char *new_uuid)
338 : {
339 0 : mutex_lock(&dm_hash_cells_mutex);
340 0 : hc->uuid = new_uuid;
341 0 : mutex_unlock(&dm_hash_cells_mutex);
342 :
343 0 : list_add(&hc->uuid_list, _uuid_buckets + hash_str(new_uuid));
344 0 : }
345 :
346 : /*
347 : * Changes the name of a hash_cell and returns the old name for
348 : * the caller to free.
349 : */
350 0 : static char *__change_cell_name(struct hash_cell *hc, char *new_name)
351 : {
352 0 : char *old_name;
353 :
354 : /*
355 : * Rename and move the name cell.
356 : */
357 0 : list_del(&hc->name_list);
358 0 : old_name = hc->name;
359 :
360 0 : mutex_lock(&dm_hash_cells_mutex);
361 0 : hc->name = new_name;
362 0 : mutex_unlock(&dm_hash_cells_mutex);
363 :
364 0 : list_add(&hc->name_list, _name_buckets + hash_str(new_name));
365 :
366 0 : return old_name;
367 : }
368 :
369 0 : static struct mapped_device *dm_hash_rename(struct dm_ioctl *param,
370 : const char *new)
371 : {
372 0 : char *new_data, *old_name = NULL;
373 0 : struct hash_cell *hc;
374 0 : struct dm_table *table;
375 0 : struct mapped_device *md;
376 0 : unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
377 0 : int srcu_idx;
378 :
379 : /*
380 : * duplicate new.
381 : */
382 0 : new_data = kstrdup(new, GFP_KERNEL);
383 0 : if (!new_data)
384 0 : return ERR_PTR(-ENOMEM);
385 :
386 0 : down_write(&_hash_lock);
387 :
388 : /*
389 : * Is new free ?
390 : */
391 0 : if (change_uuid)
392 0 : hc = __get_uuid_cell(new);
393 : else
394 0 : hc = __get_name_cell(new);
395 :
396 0 : if (hc) {
397 0 : DMWARN("Unable to change %s on mapped device %s to one that "
398 : "already exists: %s",
399 : change_uuid ? "uuid" : "name",
400 : param->name, new);
401 0 : dm_put(hc->md);
402 0 : up_write(&_hash_lock);
403 0 : kfree(new_data);
404 0 : return ERR_PTR(-EBUSY);
405 : }
406 :
407 : /*
408 : * Is there such a device as 'old' ?
409 : */
410 0 : hc = __get_name_cell(param->name);
411 0 : if (!hc) {
412 0 : DMWARN("Unable to rename non-existent device, %s to %s%s",
413 : param->name, change_uuid ? "uuid " : "", new);
414 0 : up_write(&_hash_lock);
415 0 : kfree(new_data);
416 0 : return ERR_PTR(-ENXIO);
417 : }
418 :
419 : /*
420 : * Does this device already have a uuid?
421 : */
422 0 : if (change_uuid && hc->uuid) {
423 0 : DMWARN("Unable to change uuid of mapped device %s to %s "
424 : "because uuid is already set to %s",
425 : param->name, new, hc->uuid);
426 0 : dm_put(hc->md);
427 0 : up_write(&_hash_lock);
428 0 : kfree(new_data);
429 0 : return ERR_PTR(-EINVAL);
430 : }
431 :
432 0 : if (change_uuid)
433 0 : __set_cell_uuid(hc, new_data);
434 : else
435 0 : old_name = __change_cell_name(hc, new_data);
436 :
437 : /*
438 : * Wake up any dm event waiters.
439 : */
440 0 : table = dm_get_live_table(hc->md, &srcu_idx);
441 0 : if (table)
442 0 : dm_table_event(table);
443 0 : dm_put_live_table(hc->md, srcu_idx);
444 :
445 0 : if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, param->event_nr))
446 0 : param->flags |= DM_UEVENT_GENERATED_FLAG;
447 :
448 0 : md = hc->md;
449 0 : up_write(&_hash_lock);
450 0 : kfree(old_name);
451 :
452 0 : return md;
453 : }
454 :
455 0 : void dm_deferred_remove(void)
456 : {
457 0 : dm_hash_remove_all(true, false, true);
458 0 : }
459 :
460 : /*-----------------------------------------------------------------
461 : * Implementation of the ioctl commands
462 : *---------------------------------------------------------------*/
463 : /*
464 : * All the ioctl commands get dispatched to functions with this
465 : * prototype.
466 : */
467 : typedef int (*ioctl_fn)(struct file *filp, struct dm_ioctl *param, size_t param_size);
468 :
469 0 : static int remove_all(struct file *filp, struct dm_ioctl *param, size_t param_size)
470 : {
471 0 : dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false);
472 0 : param->data_size = 0;
473 0 : return 0;
474 : }
475 :
476 : /*
477 : * Round up the ptr to an 8-byte boundary.
478 : */
479 : #define ALIGN_MASK 7
480 0 : static inline size_t align_val(size_t val)
481 : {
482 0 : return (val + ALIGN_MASK) & ~ALIGN_MASK;
483 : }
484 0 : static inline void *align_ptr(void *ptr)
485 : {
486 0 : return (void *)align_val((size_t)ptr);
487 : }
488 :
489 : /*
490 : * Retrieves the data payload buffer from an already allocated
491 : * struct dm_ioctl.
492 : */
493 0 : static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
494 : size_t *len)
495 : {
496 0 : param->data_start = align_ptr(param + 1) - (void *) param;
497 :
498 0 : if (param->data_start < param_size)
499 0 : *len = param_size - param->data_start;
500 : else
501 : *len = 0;
502 :
503 0 : return ((void *) param) + param->data_start;
504 : }
505 :
506 0 : static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_size)
507 : {
508 0 : unsigned int i;
509 0 : struct hash_cell *hc;
510 0 : size_t len, needed = 0;
511 0 : struct gendisk *disk;
512 0 : struct dm_name_list *orig_nl, *nl, *old_nl = NULL;
513 0 : uint32_t *event_nr;
514 :
515 0 : down_write(&_hash_lock);
516 :
517 : /*
518 : * Loop through all the devices working out how much
519 : * space we need.
520 : */
521 0 : for (i = 0; i < NUM_BUCKETS; i++) {
522 0 : list_for_each_entry (hc, _name_buckets + i, name_list) {
523 0 : needed += align_val(offsetof(struct dm_name_list, name) + strlen(hc->name) + 1);
524 0 : needed += align_val(sizeof(uint32_t));
525 : }
526 : }
527 :
528 : /*
529 : * Grab our output buffer.
530 : */
531 0 : nl = orig_nl = get_result_buffer(param, param_size, &len);
532 0 : if (len < needed) {
533 0 : param->flags |= DM_BUFFER_FULL_FLAG;
534 0 : goto out;
535 : }
536 0 : param->data_size = param->data_start + needed;
537 :
538 0 : nl->dev = 0; /* Flags no data */
539 :
540 : /*
541 : * Now loop through filling out the names.
542 : */
543 0 : for (i = 0; i < NUM_BUCKETS; i++) {
544 0 : list_for_each_entry (hc, _name_buckets + i, name_list) {
545 0 : if (old_nl)
546 0 : old_nl->next = (uint32_t) ((void *) nl -
547 : (void *) old_nl);
548 0 : disk = dm_disk(hc->md);
549 0 : nl->dev = huge_encode_dev(disk_devt(disk));
550 0 : nl->next = 0;
551 0 : strcpy(nl->name, hc->name);
552 :
553 0 : old_nl = nl;
554 0 : event_nr = align_ptr(nl->name + strlen(hc->name) + 1);
555 0 : *event_nr = dm_get_event_nr(hc->md);
556 0 : nl = align_ptr(event_nr + 1);
557 : }
558 : }
559 : /*
560 : * If mismatch happens, security may be compromised due to buffer
561 : * overflow, so it's better to crash.
562 : */
563 0 : BUG_ON((char *)nl - (char *)orig_nl != needed);
564 :
565 0 : out:
566 0 : up_write(&_hash_lock);
567 0 : return 0;
568 : }
569 :
570 0 : static void list_version_get_needed(struct target_type *tt, void *needed_param)
571 : {
572 0 : size_t *needed = needed_param;
573 :
574 0 : *needed += sizeof(struct dm_target_versions);
575 0 : *needed += strlen(tt->name);
576 0 : *needed += ALIGN_MASK;
577 0 : }
578 :
579 0 : static void list_version_get_info(struct target_type *tt, void *param)
580 : {
581 0 : struct vers_iter *info = param;
582 :
583 : /* Check space - it might have changed since the first iteration */
584 0 : if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 >
585 0 : info->end) {
586 :
587 0 : info->flags = DM_BUFFER_FULL_FLAG;
588 0 : return;
589 : }
590 :
591 0 : if (info->old_vers)
592 0 : info->old_vers->next = (uint32_t) ((void *)info->vers -
593 : (void *)info->old_vers);
594 0 : info->vers->version[0] = tt->version[0];
595 0 : info->vers->version[1] = tt->version[1];
596 0 : info->vers->version[2] = tt->version[2];
597 0 : info->vers->next = 0;
598 0 : strcpy(info->vers->name, tt->name);
599 :
600 0 : info->old_vers = info->vers;
601 0 : info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
602 : }
603 :
604 0 : static int __list_versions(struct dm_ioctl *param, size_t param_size, const char *name)
605 : {
606 0 : size_t len, needed = 0;
607 0 : struct dm_target_versions *vers;
608 0 : struct vers_iter iter_info;
609 0 : struct target_type *tt = NULL;
610 :
611 0 : if (name) {
612 0 : tt = dm_get_target_type(name);
613 0 : if (!tt)
614 : return -EINVAL;
615 : }
616 :
617 : /*
618 : * Loop through all the devices working out how much
619 : * space we need.
620 : */
621 0 : if (!tt)
622 0 : dm_target_iterate(list_version_get_needed, &needed);
623 : else
624 0 : list_version_get_needed(tt, &needed);
625 :
626 : /*
627 : * Grab our output buffer.
628 : */
629 0 : vers = get_result_buffer(param, param_size, &len);
630 0 : if (len < needed) {
631 0 : param->flags |= DM_BUFFER_FULL_FLAG;
632 0 : goto out;
633 : }
634 0 : param->data_size = param->data_start + needed;
635 :
636 0 : iter_info.param_size = param_size;
637 0 : iter_info.old_vers = NULL;
638 0 : iter_info.vers = vers;
639 0 : iter_info.flags = 0;
640 0 : iter_info.end = (char *)vers+len;
641 :
642 : /*
643 : * Now loop through filling out the names & versions.
644 : */
645 0 : if (!tt)
646 0 : dm_target_iterate(list_version_get_info, &iter_info);
647 : else
648 0 : list_version_get_info(tt, &iter_info);
649 0 : param->flags |= iter_info.flags;
650 :
651 0 : out:
652 0 : if (tt)
653 0 : dm_put_target_type(tt);
654 : return 0;
655 : }
656 :
657 0 : static int list_versions(struct file *filp, struct dm_ioctl *param, size_t param_size)
658 : {
659 0 : return __list_versions(param, param_size, NULL);
660 : }
661 :
662 0 : static int get_target_version(struct file *filp, struct dm_ioctl *param, size_t param_size)
663 : {
664 0 : return __list_versions(param, param_size, param->name);
665 : }
666 :
667 0 : static int check_name(const char *name)
668 : {
669 0 : if (strchr(name, '/')) {
670 0 : DMWARN("invalid device name");
671 0 : return -EINVAL;
672 : }
673 :
674 : return 0;
675 : }
676 :
677 : /*
678 : * On successful return, the caller must not attempt to acquire
679 : * _hash_lock without first calling dm_put_live_table, because dm_table_destroy
680 : * waits for this dm_put_live_table and could be called under this lock.
681 : */
682 0 : static struct dm_table *dm_get_inactive_table(struct mapped_device *md, int *srcu_idx)
683 : {
684 0 : struct hash_cell *hc;
685 0 : struct dm_table *table = NULL;
686 :
687 : /* increment rcu count, we don't care about the table pointer */
688 0 : dm_get_live_table(md, srcu_idx);
689 :
690 0 : down_read(&_hash_lock);
691 0 : hc = dm_get_mdptr(md);
692 0 : if (!hc || hc->md != md) {
693 0 : DMWARN("device has been removed from the dev hash table.");
694 0 : goto out;
695 : }
696 :
697 0 : table = hc->new_map;
698 :
699 0 : out:
700 0 : up_read(&_hash_lock);
701 :
702 0 : return table;
703 : }
704 :
705 0 : static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md,
706 : struct dm_ioctl *param,
707 : int *srcu_idx)
708 : {
709 0 : return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ?
710 0 : dm_get_inactive_table(md, srcu_idx) : dm_get_live_table(md, srcu_idx);
711 : }
712 :
713 : /*
714 : * Fills in a dm_ioctl structure, ready for sending back to
715 : * userland.
716 : */
717 0 : static void __dev_status(struct mapped_device *md, struct dm_ioctl *param)
718 : {
719 0 : struct gendisk *disk = dm_disk(md);
720 0 : struct dm_table *table;
721 0 : int srcu_idx;
722 :
723 0 : param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
724 : DM_ACTIVE_PRESENT_FLAG | DM_INTERNAL_SUSPEND_FLAG);
725 :
726 0 : if (dm_suspended_md(md))
727 0 : param->flags |= DM_SUSPEND_FLAG;
728 :
729 0 : if (dm_suspended_internally_md(md))
730 0 : param->flags |= DM_INTERNAL_SUSPEND_FLAG;
731 :
732 0 : if (dm_test_deferred_remove_flag(md))
733 0 : param->flags |= DM_DEFERRED_REMOVE;
734 :
735 0 : param->dev = huge_encode_dev(disk_devt(disk));
736 :
737 : /*
738 : * Yes, this will be out of date by the time it gets back
739 : * to userland, but it is still very useful for
740 : * debugging.
741 : */
742 0 : param->open_count = dm_open_count(md);
743 :
744 0 : param->event_nr = dm_get_event_nr(md);
745 0 : param->target_count = 0;
746 :
747 0 : table = dm_get_live_table(md, &srcu_idx);
748 0 : if (table) {
749 0 : if (!(param->flags & DM_QUERY_INACTIVE_TABLE_FLAG)) {
750 0 : if (get_disk_ro(disk))
751 0 : param->flags |= DM_READONLY_FLAG;
752 0 : param->target_count = dm_table_get_num_targets(table);
753 : }
754 :
755 0 : param->flags |= DM_ACTIVE_PRESENT_FLAG;
756 : }
757 0 : dm_put_live_table(md, srcu_idx);
758 :
759 0 : if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) {
760 0 : int srcu_idx;
761 0 : table = dm_get_inactive_table(md, &srcu_idx);
762 0 : if (table) {
763 0 : if (!(dm_table_get_mode(table) & FMODE_WRITE))
764 0 : param->flags |= DM_READONLY_FLAG;
765 0 : param->target_count = dm_table_get_num_targets(table);
766 : }
767 0 : dm_put_live_table(md, srcu_idx);
768 : }
769 0 : }
770 :
771 0 : static int dev_create(struct file *filp, struct dm_ioctl *param, size_t param_size)
772 : {
773 0 : int r, m = DM_ANY_MINOR;
774 0 : struct mapped_device *md;
775 :
776 0 : r = check_name(param->name);
777 0 : if (r)
778 : return r;
779 :
780 0 : if (param->flags & DM_PERSISTENT_DEV_FLAG)
781 0 : m = MINOR(huge_decode_dev(param->dev));
782 :
783 0 : r = dm_create(m, &md);
784 0 : if (r)
785 : return r;
786 :
787 0 : r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
788 0 : if (r) {
789 0 : dm_put(md);
790 0 : dm_destroy(md);
791 0 : return r;
792 : }
793 :
794 0 : param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
795 :
796 0 : __dev_status(md, param);
797 :
798 0 : dm_put(md);
799 :
800 0 : return 0;
801 : }
802 :
803 : /*
804 : * Always use UUID for lookups if it's present, otherwise use name or dev.
805 : */
806 0 : static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
807 : {
808 0 : struct hash_cell *hc = NULL;
809 :
810 0 : if (*param->uuid) {
811 0 : if (*param->name || param->dev)
812 : return NULL;
813 :
814 0 : hc = __get_uuid_cell(param->uuid);
815 0 : if (!hc)
816 : return NULL;
817 0 : } else if (*param->name) {
818 0 : if (param->dev)
819 : return NULL;
820 :
821 0 : hc = __get_name_cell(param->name);
822 0 : if (!hc)
823 : return NULL;
824 0 : } else if (param->dev) {
825 0 : hc = __get_dev_cell(param->dev);
826 0 : if (!hc)
827 : return NULL;
828 : } else
829 : return NULL;
830 :
831 : /*
832 : * Sneakily write in both the name and the uuid
833 : * while we have the cell.
834 : */
835 0 : strlcpy(param->name, hc->name, sizeof(param->name));
836 0 : if (hc->uuid)
837 0 : strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
838 : else
839 0 : param->uuid[0] = '\0';
840 :
841 0 : if (hc->new_map)
842 0 : param->flags |= DM_INACTIVE_PRESENT_FLAG;
843 : else
844 0 : param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
845 :
846 : return hc;
847 : }
848 :
849 0 : static struct mapped_device *find_device(struct dm_ioctl *param)
850 : {
851 0 : struct hash_cell *hc;
852 0 : struct mapped_device *md = NULL;
853 :
854 0 : down_read(&_hash_lock);
855 0 : hc = __find_device_hash_cell(param);
856 0 : if (hc)
857 0 : md = hc->md;
858 0 : up_read(&_hash_lock);
859 :
860 0 : return md;
861 : }
862 :
863 0 : static int dev_remove(struct file *filp, struct dm_ioctl *param, size_t param_size)
864 : {
865 0 : struct hash_cell *hc;
866 0 : struct mapped_device *md;
867 0 : int r;
868 0 : struct dm_table *t;
869 :
870 0 : down_write(&_hash_lock);
871 0 : hc = __find_device_hash_cell(param);
872 :
873 0 : if (!hc) {
874 0 : DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
875 0 : up_write(&_hash_lock);
876 0 : return -ENXIO;
877 : }
878 :
879 0 : md = hc->md;
880 :
881 : /*
882 : * Ensure the device is not open and nothing further can open it.
883 : */
884 0 : r = dm_lock_for_deletion(md, !!(param->flags & DM_DEFERRED_REMOVE), false);
885 0 : if (r) {
886 0 : if (r == -EBUSY && param->flags & DM_DEFERRED_REMOVE) {
887 0 : up_write(&_hash_lock);
888 0 : dm_put(md);
889 0 : return 0;
890 : }
891 0 : DMDEBUG_LIMIT("unable to remove open device %s", hc->name);
892 0 : up_write(&_hash_lock);
893 0 : dm_put(md);
894 0 : return r;
895 : }
896 :
897 0 : t = __hash_remove(hc);
898 0 : up_write(&_hash_lock);
899 :
900 0 : if (t) {
901 0 : dm_sync_table(md);
902 0 : dm_table_destroy(t);
903 : }
904 :
905 0 : param->flags &= ~DM_DEFERRED_REMOVE;
906 :
907 0 : if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr))
908 0 : param->flags |= DM_UEVENT_GENERATED_FLAG;
909 :
910 0 : dm_put(md);
911 0 : dm_destroy(md);
912 0 : return 0;
913 : }
914 :
915 : /*
916 : * Check a string doesn't overrun the chunk of
917 : * memory we copied from userland.
918 : */
919 0 : static int invalid_str(char *str, void *end)
920 : {
921 0 : while ((void *) str < end)
922 0 : if (!*str++)
923 : return 0;
924 :
925 : return -EINVAL;
926 : }
927 :
928 0 : static int dev_rename(struct file *filp, struct dm_ioctl *param, size_t param_size)
929 : {
930 0 : int r;
931 0 : char *new_data = (char *) param + param->data_start;
932 0 : struct mapped_device *md;
933 0 : unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
934 :
935 0 : if (new_data < param->data ||
936 0 : invalid_str(new_data, (void *) param + param_size) || !*new_data ||
937 0 : strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) {
938 0 : DMWARN("Invalid new mapped device name or uuid string supplied.");
939 0 : return -EINVAL;
940 : }
941 :
942 0 : if (!change_uuid) {
943 0 : r = check_name(new_data);
944 0 : if (r)
945 : return r;
946 : }
947 :
948 0 : md = dm_hash_rename(param, new_data);
949 0 : if (IS_ERR(md))
950 0 : return PTR_ERR(md);
951 :
952 0 : __dev_status(md, param);
953 0 : dm_put(md);
954 :
955 0 : return 0;
956 : }
957 :
958 0 : static int dev_set_geometry(struct file *filp, struct dm_ioctl *param, size_t param_size)
959 : {
960 0 : int r = -EINVAL, x;
961 0 : struct mapped_device *md;
962 0 : struct hd_geometry geometry;
963 0 : unsigned long indata[4];
964 0 : char *geostr = (char *) param + param->data_start;
965 0 : char dummy;
966 :
967 0 : md = find_device(param);
968 0 : if (!md)
969 : return -ENXIO;
970 :
971 0 : if (geostr < param->data ||
972 0 : invalid_str(geostr, (void *) param + param_size)) {
973 0 : DMWARN("Invalid geometry supplied.");
974 0 : goto out;
975 : }
976 :
977 0 : x = sscanf(geostr, "%lu %lu %lu %lu%c", indata,
978 : indata + 1, indata + 2, indata + 3, &dummy);
979 :
980 0 : if (x != 4) {
981 0 : DMWARN("Unable to interpret geometry settings.");
982 0 : goto out;
983 : }
984 :
985 0 : if (indata[0] > 65535 || indata[1] > 255 ||
986 0 : indata[2] > 255 || indata[3] > ULONG_MAX) {
987 0 : DMWARN("Geometry exceeds range limits.");
988 0 : goto out;
989 : }
990 :
991 0 : geometry.cylinders = indata[0];
992 0 : geometry.heads = indata[1];
993 0 : geometry.sectors = indata[2];
994 0 : geometry.start = indata[3];
995 :
996 0 : r = dm_set_geometry(md, &geometry);
997 :
998 0 : param->data_size = 0;
999 :
1000 0 : out:
1001 0 : dm_put(md);
1002 0 : return r;
1003 : }
1004 :
1005 0 : static int do_suspend(struct dm_ioctl *param)
1006 : {
1007 0 : int r = 0;
1008 0 : unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
1009 0 : struct mapped_device *md;
1010 :
1011 0 : md = find_device(param);
1012 0 : if (!md)
1013 : return -ENXIO;
1014 :
1015 0 : if (param->flags & DM_SKIP_LOCKFS_FLAG)
1016 0 : suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
1017 0 : if (param->flags & DM_NOFLUSH_FLAG)
1018 0 : suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
1019 :
1020 0 : if (!dm_suspended_md(md)) {
1021 0 : r = dm_suspend(md, suspend_flags);
1022 0 : if (r)
1023 0 : goto out;
1024 : }
1025 :
1026 0 : __dev_status(md, param);
1027 :
1028 0 : out:
1029 0 : dm_put(md);
1030 :
1031 0 : return r;
1032 : }
1033 :
1034 0 : static int do_resume(struct dm_ioctl *param)
1035 : {
1036 0 : int r = 0;
1037 0 : unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
1038 0 : struct hash_cell *hc;
1039 0 : struct mapped_device *md;
1040 0 : struct dm_table *new_map, *old_map = NULL;
1041 :
1042 0 : down_write(&_hash_lock);
1043 :
1044 0 : hc = __find_device_hash_cell(param);
1045 0 : if (!hc) {
1046 0 : DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
1047 0 : up_write(&_hash_lock);
1048 0 : return -ENXIO;
1049 : }
1050 :
1051 0 : md = hc->md;
1052 :
1053 0 : new_map = hc->new_map;
1054 0 : hc->new_map = NULL;
1055 0 : param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1056 :
1057 0 : up_write(&_hash_lock);
1058 :
1059 : /* Do we need to load a new map ? */
1060 0 : if (new_map) {
1061 : /* Suspend if it isn't already suspended */
1062 0 : if (param->flags & DM_SKIP_LOCKFS_FLAG)
1063 0 : suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
1064 0 : if (param->flags & DM_NOFLUSH_FLAG)
1065 0 : suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
1066 0 : if (!dm_suspended_md(md))
1067 0 : dm_suspend(md, suspend_flags);
1068 :
1069 0 : old_map = dm_swap_table(md, new_map);
1070 0 : if (IS_ERR(old_map)) {
1071 0 : dm_sync_table(md);
1072 0 : dm_table_destroy(new_map);
1073 0 : dm_put(md);
1074 0 : return PTR_ERR(old_map);
1075 : }
1076 :
1077 0 : if (dm_table_get_mode(new_map) & FMODE_WRITE)
1078 0 : set_disk_ro(dm_disk(md), 0);
1079 : else
1080 0 : set_disk_ro(dm_disk(md), 1);
1081 : }
1082 :
1083 0 : if (dm_suspended_md(md)) {
1084 0 : r = dm_resume(md);
1085 0 : if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
1086 0 : param->flags |= DM_UEVENT_GENERATED_FLAG;
1087 : }
1088 :
1089 : /*
1090 : * Since dm_swap_table synchronizes RCU, nobody should be in
1091 : * read-side critical section already.
1092 : */
1093 0 : if (old_map)
1094 0 : dm_table_destroy(old_map);
1095 :
1096 0 : if (!r)
1097 0 : __dev_status(md, param);
1098 :
1099 0 : dm_put(md);
1100 0 : return r;
1101 : }
1102 :
1103 : /*
1104 : * Set or unset the suspension state of a device.
1105 : * If the device already is in the requested state we just return its status.
1106 : */
1107 0 : static int dev_suspend(struct file *filp, struct dm_ioctl *param, size_t param_size)
1108 : {
1109 0 : if (param->flags & DM_SUSPEND_FLAG)
1110 0 : return do_suspend(param);
1111 :
1112 0 : return do_resume(param);
1113 : }
1114 :
1115 : /*
1116 : * Copies device info back to user space, used by
1117 : * the create and info ioctls.
1118 : */
1119 0 : static int dev_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
1120 : {
1121 0 : struct mapped_device *md;
1122 :
1123 0 : md = find_device(param);
1124 0 : if (!md)
1125 : return -ENXIO;
1126 :
1127 0 : __dev_status(md, param);
1128 0 : dm_put(md);
1129 :
1130 0 : return 0;
1131 : }
1132 :
1133 : /*
1134 : * Build up the status struct for each target
1135 : */
1136 0 : static void retrieve_status(struct dm_table *table,
1137 : struct dm_ioctl *param, size_t param_size)
1138 : {
1139 0 : unsigned int i, num_targets;
1140 0 : struct dm_target_spec *spec;
1141 0 : char *outbuf, *outptr;
1142 0 : status_type_t type;
1143 0 : size_t remaining, len, used = 0;
1144 0 : unsigned status_flags = 0;
1145 :
1146 0 : outptr = outbuf = get_result_buffer(param, param_size, &len);
1147 :
1148 0 : if (param->flags & DM_STATUS_TABLE_FLAG)
1149 : type = STATUSTYPE_TABLE;
1150 : else
1151 0 : type = STATUSTYPE_INFO;
1152 :
1153 : /* Get all the target info */
1154 0 : num_targets = dm_table_get_num_targets(table);
1155 0 : for (i = 0; i < num_targets; i++) {
1156 0 : struct dm_target *ti = dm_table_get_target(table, i);
1157 0 : size_t l;
1158 :
1159 0 : remaining = len - (outptr - outbuf);
1160 0 : if (remaining <= sizeof(struct dm_target_spec)) {
1161 0 : param->flags |= DM_BUFFER_FULL_FLAG;
1162 0 : break;
1163 : }
1164 :
1165 0 : spec = (struct dm_target_spec *) outptr;
1166 :
1167 0 : spec->status = 0;
1168 0 : spec->sector_start = ti->begin;
1169 0 : spec->length = ti->len;
1170 0 : strncpy(spec->target_type, ti->type->name,
1171 : sizeof(spec->target_type) - 1);
1172 :
1173 0 : outptr += sizeof(struct dm_target_spec);
1174 0 : remaining = len - (outptr - outbuf);
1175 0 : if (remaining <= 0) {
1176 0 : param->flags |= DM_BUFFER_FULL_FLAG;
1177 0 : break;
1178 : }
1179 :
1180 : /* Get the status/table string from the target driver */
1181 0 : if (ti->type->status) {
1182 0 : if (param->flags & DM_NOFLUSH_FLAG)
1183 0 : status_flags |= DM_STATUS_NOFLUSH_FLAG;
1184 0 : ti->type->status(ti, type, status_flags, outptr, remaining);
1185 : } else
1186 0 : outptr[0] = '\0';
1187 :
1188 0 : l = strlen(outptr) + 1;
1189 0 : if (l == remaining) {
1190 0 : param->flags |= DM_BUFFER_FULL_FLAG;
1191 0 : break;
1192 : }
1193 :
1194 0 : outptr += l;
1195 0 : used = param->data_start + (outptr - outbuf);
1196 :
1197 0 : outptr = align_ptr(outptr);
1198 0 : spec->next = outptr - outbuf;
1199 : }
1200 :
1201 0 : if (used)
1202 0 : param->data_size = used;
1203 :
1204 0 : param->target_count = num_targets;
1205 0 : }
1206 :
1207 : /*
1208 : * Wait for a device to report an event
1209 : */
1210 0 : static int dev_wait(struct file *filp, struct dm_ioctl *param, size_t param_size)
1211 : {
1212 0 : int r = 0;
1213 0 : struct mapped_device *md;
1214 0 : struct dm_table *table;
1215 0 : int srcu_idx;
1216 :
1217 0 : md = find_device(param);
1218 0 : if (!md)
1219 : return -ENXIO;
1220 :
1221 : /*
1222 : * Wait for a notification event
1223 : */
1224 0 : if (dm_wait_event(md, param->event_nr)) {
1225 0 : r = -ERESTARTSYS;
1226 0 : goto out;
1227 : }
1228 :
1229 : /*
1230 : * The userland program is going to want to know what
1231 : * changed to trigger the event, so we may as well tell
1232 : * him and save an ioctl.
1233 : */
1234 0 : __dev_status(md, param);
1235 :
1236 0 : table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1237 0 : if (table)
1238 0 : retrieve_status(table, param, param_size);
1239 0 : dm_put_live_table(md, srcu_idx);
1240 :
1241 0 : out:
1242 0 : dm_put(md);
1243 :
1244 0 : return r;
1245 : }
1246 :
1247 : /*
1248 : * Remember the global event number and make it possible to poll
1249 : * for further events.
1250 : */
1251 0 : static int dev_arm_poll(struct file *filp, struct dm_ioctl *param, size_t param_size)
1252 : {
1253 0 : struct dm_file *priv = filp->private_data;
1254 :
1255 0 : priv->global_event_nr = atomic_read(&dm_global_event_nr);
1256 :
1257 0 : return 0;
1258 : }
1259 :
1260 0 : static inline fmode_t get_mode(struct dm_ioctl *param)
1261 : {
1262 0 : fmode_t mode = FMODE_READ | FMODE_WRITE;
1263 :
1264 0 : if (param->flags & DM_READONLY_FLAG)
1265 0 : mode = FMODE_READ;
1266 :
1267 0 : return mode;
1268 : }
1269 :
1270 0 : static int next_target(struct dm_target_spec *last, uint32_t next, void *end,
1271 : struct dm_target_spec **spec, char **target_params)
1272 : {
1273 0 : *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
1274 0 : *target_params = (char *) (*spec + 1);
1275 :
1276 0 : if (*spec < (last + 1))
1277 : return -EINVAL;
1278 :
1279 0 : return invalid_str(*target_params, end);
1280 : }
1281 :
1282 0 : static int populate_table(struct dm_table *table,
1283 : struct dm_ioctl *param, size_t param_size)
1284 : {
1285 0 : int r;
1286 0 : unsigned int i = 0;
1287 0 : struct dm_target_spec *spec = (struct dm_target_spec *) param;
1288 0 : uint32_t next = param->data_start;
1289 0 : void *end = (void *) param + param_size;
1290 0 : char *target_params;
1291 :
1292 0 : if (!param->target_count) {
1293 0 : DMWARN("populate_table: no targets specified");
1294 0 : return -EINVAL;
1295 : }
1296 :
1297 0 : for (i = 0; i < param->target_count; i++) {
1298 :
1299 0 : r = next_target(spec, next, end, &spec, &target_params);
1300 0 : if (r) {
1301 0 : DMWARN("unable to find target");
1302 0 : return r;
1303 : }
1304 :
1305 0 : r = dm_table_add_target(table, spec->target_type,
1306 0 : (sector_t) spec->sector_start,
1307 0 : (sector_t) spec->length,
1308 : target_params);
1309 0 : if (r) {
1310 0 : DMWARN("error adding target to table");
1311 0 : return r;
1312 : }
1313 :
1314 0 : next = spec->next;
1315 : }
1316 :
1317 0 : return dm_table_complete(table);
1318 : }
1319 :
1320 0 : static bool is_valid_type(enum dm_queue_mode cur, enum dm_queue_mode new)
1321 : {
1322 0 : if (cur == new ||
1323 0 : (cur == DM_TYPE_BIO_BASED && new == DM_TYPE_DAX_BIO_BASED))
1324 : return true;
1325 :
1326 : return false;
1327 : }
1328 :
1329 0 : static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_size)
1330 : {
1331 0 : int r;
1332 0 : struct hash_cell *hc;
1333 0 : struct dm_table *t, *old_map = NULL;
1334 0 : struct mapped_device *md;
1335 0 : struct target_type *immutable_target_type;
1336 :
1337 0 : md = find_device(param);
1338 0 : if (!md)
1339 : return -ENXIO;
1340 :
1341 0 : r = dm_table_create(&t, get_mode(param), param->target_count, md);
1342 0 : if (r)
1343 0 : goto err;
1344 :
1345 : /* Protect md->type and md->queue against concurrent table loads. */
1346 0 : dm_lock_md_type(md);
1347 0 : r = populate_table(t, param, param_size);
1348 0 : if (r)
1349 0 : goto err_unlock_md_type;
1350 :
1351 0 : immutable_target_type = dm_get_immutable_target_type(md);
1352 0 : if (immutable_target_type &&
1353 0 : (immutable_target_type != dm_table_get_immutable_target_type(t)) &&
1354 0 : !dm_table_get_wildcard_target(t)) {
1355 0 : DMWARN("can't replace immutable target type %s",
1356 : immutable_target_type->name);
1357 0 : r = -EINVAL;
1358 0 : goto err_unlock_md_type;
1359 : }
1360 :
1361 0 : if (dm_get_md_type(md) == DM_TYPE_NONE) {
1362 : /* Initial table load: acquire type of table. */
1363 0 : dm_set_md_type(md, dm_table_get_type(t));
1364 :
1365 : /* setup md->queue to reflect md's type (may block) */
1366 0 : r = dm_setup_md_queue(md, t);
1367 0 : if (r) {
1368 0 : DMWARN("unable to set up device queue for new table.");
1369 0 : goto err_unlock_md_type;
1370 : }
1371 0 : } else if (!is_valid_type(dm_get_md_type(md), dm_table_get_type(t))) {
1372 0 : DMWARN("can't change device type (old=%u vs new=%u) after initial table load.",
1373 : dm_get_md_type(md), dm_table_get_type(t));
1374 0 : r = -EINVAL;
1375 0 : goto err_unlock_md_type;
1376 : }
1377 :
1378 0 : dm_unlock_md_type(md);
1379 :
1380 : /* stage inactive table */
1381 0 : down_write(&_hash_lock);
1382 0 : hc = dm_get_mdptr(md);
1383 0 : if (!hc || hc->md != md) {
1384 0 : DMWARN("device has been removed from the dev hash table.");
1385 0 : up_write(&_hash_lock);
1386 0 : r = -ENXIO;
1387 0 : goto err_destroy_table;
1388 : }
1389 :
1390 0 : if (hc->new_map)
1391 0 : old_map = hc->new_map;
1392 0 : hc->new_map = t;
1393 0 : up_write(&_hash_lock);
1394 :
1395 0 : param->flags |= DM_INACTIVE_PRESENT_FLAG;
1396 0 : __dev_status(md, param);
1397 :
1398 0 : if (old_map) {
1399 0 : dm_sync_table(md);
1400 0 : dm_table_destroy(old_map);
1401 : }
1402 :
1403 0 : dm_put(md);
1404 :
1405 0 : return 0;
1406 :
1407 0 : err_unlock_md_type:
1408 0 : dm_unlock_md_type(md);
1409 0 : err_destroy_table:
1410 0 : dm_table_destroy(t);
1411 0 : err:
1412 0 : dm_put(md);
1413 :
1414 0 : return r;
1415 : }
1416 :
1417 0 : static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_size)
1418 : {
1419 0 : struct hash_cell *hc;
1420 0 : struct mapped_device *md;
1421 0 : struct dm_table *old_map = NULL;
1422 :
1423 0 : down_write(&_hash_lock);
1424 :
1425 0 : hc = __find_device_hash_cell(param);
1426 0 : if (!hc) {
1427 0 : DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
1428 0 : up_write(&_hash_lock);
1429 0 : return -ENXIO;
1430 : }
1431 :
1432 0 : if (hc->new_map) {
1433 0 : old_map = hc->new_map;
1434 0 : hc->new_map = NULL;
1435 : }
1436 :
1437 0 : param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1438 :
1439 0 : __dev_status(hc->md, param);
1440 0 : md = hc->md;
1441 0 : up_write(&_hash_lock);
1442 0 : if (old_map) {
1443 0 : dm_sync_table(md);
1444 0 : dm_table_destroy(old_map);
1445 : }
1446 0 : dm_put(md);
1447 :
1448 0 : return 0;
1449 : }
1450 :
1451 : /*
1452 : * Retrieves a list of devices used by a particular dm device.
1453 : */
1454 0 : static void retrieve_deps(struct dm_table *table,
1455 : struct dm_ioctl *param, size_t param_size)
1456 : {
1457 0 : unsigned int count = 0;
1458 0 : struct list_head *tmp;
1459 0 : size_t len, needed;
1460 0 : struct dm_dev_internal *dd;
1461 0 : struct dm_target_deps *deps;
1462 :
1463 0 : deps = get_result_buffer(param, param_size, &len);
1464 :
1465 : /*
1466 : * Count the devices.
1467 : */
1468 0 : list_for_each (tmp, dm_table_get_devices(table))
1469 0 : count++;
1470 :
1471 : /*
1472 : * Check we have enough space.
1473 : */
1474 0 : needed = struct_size(deps, dev, count);
1475 0 : if (len < needed) {
1476 0 : param->flags |= DM_BUFFER_FULL_FLAG;
1477 0 : return;
1478 : }
1479 :
1480 : /*
1481 : * Fill in the devices.
1482 : */
1483 0 : deps->count = count;
1484 0 : count = 0;
1485 0 : list_for_each_entry (dd, dm_table_get_devices(table), list)
1486 0 : deps->dev[count++] = huge_encode_dev(dd->dm_dev->bdev->bd_dev);
1487 :
1488 0 : param->data_size = param->data_start + needed;
1489 : }
1490 :
1491 0 : static int table_deps(struct file *filp, struct dm_ioctl *param, size_t param_size)
1492 : {
1493 0 : struct mapped_device *md;
1494 0 : struct dm_table *table;
1495 0 : int srcu_idx;
1496 :
1497 0 : md = find_device(param);
1498 0 : if (!md)
1499 : return -ENXIO;
1500 :
1501 0 : __dev_status(md, param);
1502 :
1503 0 : table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1504 0 : if (table)
1505 0 : retrieve_deps(table, param, param_size);
1506 0 : dm_put_live_table(md, srcu_idx);
1507 :
1508 0 : dm_put(md);
1509 :
1510 0 : return 0;
1511 : }
1512 :
1513 : /*
1514 : * Return the status of a device as a text string for each
1515 : * target.
1516 : */
1517 0 : static int table_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
1518 : {
1519 0 : struct mapped_device *md;
1520 0 : struct dm_table *table;
1521 0 : int srcu_idx;
1522 :
1523 0 : md = find_device(param);
1524 0 : if (!md)
1525 : return -ENXIO;
1526 :
1527 0 : __dev_status(md, param);
1528 :
1529 0 : table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1530 0 : if (table)
1531 0 : retrieve_status(table, param, param_size);
1532 0 : dm_put_live_table(md, srcu_idx);
1533 :
1534 0 : dm_put(md);
1535 :
1536 0 : return 0;
1537 : }
1538 :
1539 : /*
1540 : * Process device-mapper dependent messages. Messages prefixed with '@'
1541 : * are processed by the DM core. All others are delivered to the target.
1542 : * Returns a number <= 1 if message was processed by device mapper.
1543 : * Returns 2 if message should be delivered to the target.
1544 : */
1545 0 : static int message_for_md(struct mapped_device *md, unsigned argc, char **argv,
1546 : char *result, unsigned maxlen)
1547 : {
1548 0 : int r;
1549 :
1550 0 : if (**argv != '@')
1551 : return 2; /* no '@' prefix, deliver to target */
1552 :
1553 0 : if (!strcasecmp(argv[0], "@cancel_deferred_remove")) {
1554 0 : if (argc != 1) {
1555 0 : DMERR("Invalid arguments for @cancel_deferred_remove");
1556 0 : return -EINVAL;
1557 : }
1558 0 : return dm_cancel_deferred_remove(md);
1559 : }
1560 :
1561 0 : r = dm_stats_message(md, argc, argv, result, maxlen);
1562 0 : if (r < 2)
1563 : return r;
1564 :
1565 0 : DMERR("Unsupported message sent to DM core: %s", argv[0]);
1566 0 : return -EINVAL;
1567 : }
1568 :
1569 : /*
1570 : * Pass a message to the target that's at the supplied device offset.
1571 : */
1572 0 : static int target_message(struct file *filp, struct dm_ioctl *param, size_t param_size)
1573 : {
1574 0 : int r, argc;
1575 0 : char **argv;
1576 0 : struct mapped_device *md;
1577 0 : struct dm_table *table;
1578 0 : struct dm_target *ti;
1579 0 : struct dm_target_msg *tmsg = (void *) param + param->data_start;
1580 0 : size_t maxlen;
1581 0 : char *result = get_result_buffer(param, param_size, &maxlen);
1582 0 : int srcu_idx;
1583 :
1584 0 : md = find_device(param);
1585 0 : if (!md)
1586 : return -ENXIO;
1587 :
1588 0 : if (tmsg < (struct dm_target_msg *) param->data ||
1589 0 : invalid_str(tmsg->message, (void *) param + param_size)) {
1590 0 : DMWARN("Invalid target message parameters.");
1591 0 : r = -EINVAL;
1592 0 : goto out;
1593 : }
1594 :
1595 0 : r = dm_split_args(&argc, &argv, tmsg->message);
1596 0 : if (r) {
1597 0 : DMWARN("Failed to split target message parameters");
1598 0 : goto out;
1599 : }
1600 :
1601 0 : if (!argc) {
1602 0 : DMWARN("Empty message received.");
1603 0 : r = -EINVAL;
1604 0 : goto out_argv;
1605 : }
1606 :
1607 0 : r = message_for_md(md, argc, argv, result, maxlen);
1608 0 : if (r <= 1)
1609 0 : goto out_argv;
1610 :
1611 0 : table = dm_get_live_table(md, &srcu_idx);
1612 0 : if (!table)
1613 0 : goto out_table;
1614 :
1615 0 : if (dm_deleting_md(md)) {
1616 0 : r = -ENXIO;
1617 0 : goto out_table;
1618 : }
1619 :
1620 0 : ti = dm_table_find_target(table, tmsg->sector);
1621 0 : if (!ti) {
1622 0 : DMWARN("Target message sector outside device.");
1623 0 : r = -EINVAL;
1624 0 : } else if (ti->type->message)
1625 0 : r = ti->type->message(ti, argc, argv, result, maxlen);
1626 : else {
1627 0 : DMWARN("Target type does not support messages");
1628 0 : r = -EINVAL;
1629 : }
1630 :
1631 0 : out_table:
1632 0 : dm_put_live_table(md, srcu_idx);
1633 0 : out_argv:
1634 0 : kfree(argv);
1635 0 : out:
1636 0 : if (r >= 0)
1637 0 : __dev_status(md, param);
1638 :
1639 0 : if (r == 1) {
1640 0 : param->flags |= DM_DATA_OUT_FLAG;
1641 0 : if (dm_message_test_buffer_overflow(result, maxlen))
1642 0 : param->flags |= DM_BUFFER_FULL_FLAG;
1643 : else
1644 0 : param->data_size = param->data_start + strlen(result) + 1;
1645 : r = 0;
1646 : }
1647 :
1648 0 : dm_put(md);
1649 0 : return r;
1650 : }
1651 :
1652 : /*
1653 : * The ioctl parameter block consists of two parts, a dm_ioctl struct
1654 : * followed by a data buffer. This flag is set if the second part,
1655 : * which has a variable size, is not used by the function processing
1656 : * the ioctl.
1657 : */
1658 : #define IOCTL_FLAGS_NO_PARAMS 1
1659 : #define IOCTL_FLAGS_ISSUE_GLOBAL_EVENT 2
1660 :
1661 : /*-----------------------------------------------------------------
1662 : * Implementation of open/close/ioctl on the special char
1663 : * device.
1664 : *---------------------------------------------------------------*/
1665 0 : static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
1666 : {
1667 0 : static const struct {
1668 : int cmd;
1669 : int flags;
1670 : ioctl_fn fn;
1671 : } _ioctls[] = {
1672 : {DM_VERSION_CMD, 0, NULL}, /* version is dealt with elsewhere */
1673 : {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, remove_all},
1674 : {DM_LIST_DEVICES_CMD, 0, list_devices},
1675 :
1676 : {DM_DEV_CREATE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_create},
1677 : {DM_DEV_REMOVE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_remove},
1678 : {DM_DEV_RENAME_CMD, IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_rename},
1679 : {DM_DEV_SUSPEND_CMD, IOCTL_FLAGS_NO_PARAMS, dev_suspend},
1680 : {DM_DEV_STATUS_CMD, IOCTL_FLAGS_NO_PARAMS, dev_status},
1681 : {DM_DEV_WAIT_CMD, 0, dev_wait},
1682 :
1683 : {DM_TABLE_LOAD_CMD, 0, table_load},
1684 : {DM_TABLE_CLEAR_CMD, IOCTL_FLAGS_NO_PARAMS, table_clear},
1685 : {DM_TABLE_DEPS_CMD, 0, table_deps},
1686 : {DM_TABLE_STATUS_CMD, 0, table_status},
1687 :
1688 : {DM_LIST_VERSIONS_CMD, 0, list_versions},
1689 :
1690 : {DM_TARGET_MSG_CMD, 0, target_message},
1691 : {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry},
1692 : {DM_DEV_ARM_POLL, IOCTL_FLAGS_NO_PARAMS, dev_arm_poll},
1693 : {DM_GET_TARGET_VERSION, 0, get_target_version},
1694 : };
1695 :
1696 0 : if (unlikely(cmd >= ARRAY_SIZE(_ioctls)))
1697 : return NULL;
1698 :
1699 0 : *ioctl_flags = _ioctls[cmd].flags;
1700 0 : return _ioctls[cmd].fn;
1701 : }
1702 :
1703 : /*
1704 : * As well as checking the version compatibility this always
1705 : * copies the kernel interface version out.
1706 : */
1707 0 : static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
1708 : {
1709 0 : uint32_t version[3];
1710 0 : int r = 0;
1711 :
1712 0 : if (copy_from_user(version, user->version, sizeof(version)))
1713 : return -EFAULT;
1714 :
1715 0 : if ((DM_VERSION_MAJOR != version[0]) ||
1716 0 : (DM_VERSION_MINOR < version[1])) {
1717 0 : DMWARN("ioctl interface mismatch: "
1718 : "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1719 : DM_VERSION_MAJOR, DM_VERSION_MINOR,
1720 : DM_VERSION_PATCHLEVEL,
1721 : version[0], version[1], version[2], cmd);
1722 0 : r = -EINVAL;
1723 : }
1724 :
1725 : /*
1726 : * Fill in the kernel version.
1727 : */
1728 0 : version[0] = DM_VERSION_MAJOR;
1729 0 : version[1] = DM_VERSION_MINOR;
1730 0 : version[2] = DM_VERSION_PATCHLEVEL;
1731 0 : if (copy_to_user(user->version, version, sizeof(version)))
1732 0 : return -EFAULT;
1733 :
1734 : return r;
1735 : }
1736 :
1737 : #define DM_PARAMS_MALLOC 0x0001 /* Params allocated with kvmalloc() */
1738 : #define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */
1739 :
1740 0 : static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags)
1741 : {
1742 0 : if (param_flags & DM_WIPE_BUFFER)
1743 0 : memset(param, 0, param_size);
1744 :
1745 0 : if (param_flags & DM_PARAMS_MALLOC)
1746 0 : kvfree(param);
1747 0 : }
1748 :
1749 0 : static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel,
1750 : int ioctl_flags, struct dm_ioctl **param, int *param_flags)
1751 : {
1752 0 : struct dm_ioctl *dmi;
1753 0 : int secure_data;
1754 0 : const size_t minimum_data_size = offsetof(struct dm_ioctl, data);
1755 0 : unsigned noio_flag;
1756 :
1757 0 : if (copy_from_user(param_kernel, user, minimum_data_size))
1758 0 : return -EFAULT;
1759 :
1760 0 : if (param_kernel->data_size < minimum_data_size)
1761 : return -EINVAL;
1762 :
1763 0 : secure_data = param_kernel->flags & DM_SECURE_DATA_FLAG;
1764 :
1765 0 : *param_flags = secure_data ? DM_WIPE_BUFFER : 0;
1766 :
1767 0 : if (ioctl_flags & IOCTL_FLAGS_NO_PARAMS) {
1768 0 : dmi = param_kernel;
1769 0 : dmi->data_size = minimum_data_size;
1770 0 : goto data_copied;
1771 : }
1772 :
1773 : /*
1774 : * Use __GFP_HIGH to avoid low memory issues when a device is
1775 : * suspended and the ioctl is needed to resume it.
1776 : * Use kmalloc() rather than vmalloc() when we can.
1777 : */
1778 0 : dmi = NULL;
1779 0 : noio_flag = memalloc_noio_save();
1780 0 : dmi = kvmalloc(param_kernel->data_size, GFP_KERNEL | __GFP_HIGH);
1781 0 : memalloc_noio_restore(noio_flag);
1782 :
1783 0 : if (!dmi) {
1784 0 : if (secure_data && clear_user(user, param_kernel->data_size))
1785 : return -EFAULT;
1786 0 : return -ENOMEM;
1787 : }
1788 :
1789 0 : *param_flags |= DM_PARAMS_MALLOC;
1790 :
1791 : /* Copy from param_kernel (which was already copied from user) */
1792 0 : memcpy(dmi, param_kernel, minimum_data_size);
1793 :
1794 0 : if (copy_from_user(&dmi->data, (char __user *)user + minimum_data_size,
1795 0 : param_kernel->data_size - minimum_data_size))
1796 0 : goto bad;
1797 0 : data_copied:
1798 : /* Wipe the user buffer so we do not return it to userspace */
1799 0 : if (secure_data && clear_user(user, param_kernel->data_size))
1800 0 : goto bad;
1801 :
1802 0 : *param = dmi;
1803 0 : return 0;
1804 :
1805 0 : bad:
1806 0 : free_params(dmi, param_kernel->data_size, *param_flags);
1807 :
1808 0 : return -EFAULT;
1809 : }
1810 :
1811 0 : static int validate_params(uint cmd, struct dm_ioctl *param)
1812 : {
1813 : /* Always clear this flag */
1814 0 : param->flags &= ~DM_BUFFER_FULL_FLAG;
1815 0 : param->flags &= ~DM_UEVENT_GENERATED_FLAG;
1816 0 : param->flags &= ~DM_SECURE_DATA_FLAG;
1817 0 : param->flags &= ~DM_DATA_OUT_FLAG;
1818 :
1819 : /* Ignores parameters */
1820 0 : if (cmd == DM_REMOVE_ALL_CMD ||
1821 0 : cmd == DM_LIST_DEVICES_CMD ||
1822 0 : cmd == DM_LIST_VERSIONS_CMD)
1823 : return 0;
1824 :
1825 0 : if (cmd == DM_DEV_CREATE_CMD) {
1826 0 : if (!*param->name) {
1827 0 : DMWARN("name not supplied when creating device");
1828 0 : return -EINVAL;
1829 : }
1830 0 : } else if (*param->uuid && *param->name) {
1831 0 : DMWARN("only supply one of name or uuid, cmd(%u)", cmd);
1832 0 : return -EINVAL;
1833 : }
1834 :
1835 : /* Ensure strings are terminated */
1836 0 : param->name[DM_NAME_LEN - 1] = '\0';
1837 0 : param->uuid[DM_UUID_LEN - 1] = '\0';
1838 :
1839 0 : return 0;
1840 : }
1841 :
1842 0 : static int ctl_ioctl(struct file *file, uint command, struct dm_ioctl __user *user)
1843 : {
1844 0 : int r = 0;
1845 0 : int ioctl_flags;
1846 0 : int param_flags;
1847 0 : unsigned int cmd;
1848 0 : struct dm_ioctl *param;
1849 0 : ioctl_fn fn = NULL;
1850 0 : size_t input_param_size;
1851 0 : struct dm_ioctl param_kernel;
1852 :
1853 : /* only root can play with this */
1854 0 : if (!capable(CAP_SYS_ADMIN))
1855 : return -EACCES;
1856 :
1857 0 : if (_IOC_TYPE(command) != DM_IOCTL)
1858 : return -ENOTTY;
1859 :
1860 0 : cmd = _IOC_NR(command);
1861 :
1862 : /*
1863 : * Check the interface version passed in. This also
1864 : * writes out the kernel's interface version.
1865 : */
1866 0 : r = check_version(cmd, user);
1867 0 : if (r)
1868 : return r;
1869 :
1870 : /*
1871 : * Nothing more to do for the version command.
1872 : */
1873 0 : if (cmd == DM_VERSION_CMD)
1874 : return 0;
1875 :
1876 0 : fn = lookup_ioctl(cmd, &ioctl_flags);
1877 0 : if (!fn) {
1878 0 : DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
1879 0 : return -ENOTTY;
1880 : }
1881 :
1882 : /*
1883 : * Copy the parameters into kernel space.
1884 : */
1885 0 : r = copy_params(user, ¶m_kernel, ioctl_flags, ¶m, ¶m_flags);
1886 :
1887 0 : if (r)
1888 : return r;
1889 :
1890 0 : input_param_size = param->data_size;
1891 0 : r = validate_params(cmd, param);
1892 0 : if (r)
1893 0 : goto out;
1894 :
1895 0 : param->data_size = offsetof(struct dm_ioctl, data);
1896 0 : r = fn(file, param, input_param_size);
1897 :
1898 0 : if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) &&
1899 0 : unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS))
1900 0 : DMERR("ioctl %d tried to output some data but has IOCTL_FLAGS_NO_PARAMS set", cmd);
1901 :
1902 0 : if (!r && ioctl_flags & IOCTL_FLAGS_ISSUE_GLOBAL_EVENT)
1903 0 : dm_issue_global_event();
1904 :
1905 : /*
1906 : * Copy the results back to userland.
1907 : */
1908 0 : if (!r && copy_to_user(user, param, param->data_size))
1909 0 : r = -EFAULT;
1910 :
1911 0 : out:
1912 0 : free_params(param, input_param_size, param_flags);
1913 0 : return r;
1914 : }
1915 :
1916 0 : static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
1917 : {
1918 0 : return (long)ctl_ioctl(file, command, (struct dm_ioctl __user *)u);
1919 : }
1920 :
1921 : #ifdef CONFIG_COMPAT
1922 0 : static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
1923 : {
1924 0 : return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
1925 : }
1926 : #else
1927 : #define dm_compat_ctl_ioctl NULL
1928 : #endif
1929 :
1930 0 : static int dm_open(struct inode *inode, struct file *filp)
1931 : {
1932 0 : int r;
1933 0 : struct dm_file *priv;
1934 :
1935 0 : r = nonseekable_open(inode, filp);
1936 0 : if (unlikely(r))
1937 : return r;
1938 :
1939 0 : priv = filp->private_data = kmalloc(sizeof(struct dm_file), GFP_KERNEL);
1940 0 : if (!priv)
1941 : return -ENOMEM;
1942 :
1943 0 : priv->global_event_nr = atomic_read(&dm_global_event_nr);
1944 :
1945 0 : return 0;
1946 : }
1947 :
1948 0 : static int dm_release(struct inode *inode, struct file *filp)
1949 : {
1950 0 : kfree(filp->private_data);
1951 0 : return 0;
1952 : }
1953 :
1954 0 : static __poll_t dm_poll(struct file *filp, poll_table *wait)
1955 : {
1956 0 : struct dm_file *priv = filp->private_data;
1957 0 : __poll_t mask = 0;
1958 :
1959 0 : poll_wait(filp, &dm_global_eventq, wait);
1960 :
1961 0 : if ((int)(atomic_read(&dm_global_event_nr) - priv->global_event_nr) > 0)
1962 0 : mask |= EPOLLIN;
1963 :
1964 0 : return mask;
1965 : }
1966 :
1967 : static const struct file_operations _ctl_fops = {
1968 : .open = dm_open,
1969 : .release = dm_release,
1970 : .poll = dm_poll,
1971 : .unlocked_ioctl = dm_ctl_ioctl,
1972 : .compat_ioctl = dm_compat_ctl_ioctl,
1973 : .owner = THIS_MODULE,
1974 : .llseek = noop_llseek,
1975 : };
1976 :
1977 : static struct miscdevice _dm_misc = {
1978 : .minor = MAPPER_CTRL_MINOR,
1979 : .name = DM_NAME,
1980 : .nodename = DM_DIR "/" DM_CONTROL_NODE,
1981 : .fops = &_ctl_fops
1982 : };
1983 :
1984 : MODULE_ALIAS_MISCDEV(MAPPER_CTRL_MINOR);
1985 : MODULE_ALIAS("devname:" DM_DIR "/" DM_CONTROL_NODE);
1986 :
1987 : /*
1988 : * Create misc character device and link to DM_DIR/control.
1989 : */
1990 1 : int __init dm_interface_init(void)
1991 : {
1992 1 : int r;
1993 :
1994 1 : r = dm_hash_init();
1995 1 : if (r)
1996 : return r;
1997 :
1998 1 : r = misc_register(&_dm_misc);
1999 1 : if (r) {
2000 0 : DMERR("misc_register failed for control device");
2001 0 : dm_hash_exit();
2002 0 : return r;
2003 : }
2004 :
2005 1 : DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
2006 : DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
2007 : DM_DRIVER_EMAIL);
2008 1 : return 0;
2009 : }
2010 :
2011 0 : void dm_interface_exit(void)
2012 : {
2013 0 : misc_deregister(&_dm_misc);
2014 0 : dm_hash_exit();
2015 0 : }
2016 :
2017 : /**
2018 : * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
2019 : * @md: Pointer to mapped_device
2020 : * @name: Buffer (size DM_NAME_LEN) for name
2021 : * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
2022 : */
2023 0 : int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
2024 : {
2025 0 : int r = 0;
2026 0 : struct hash_cell *hc;
2027 :
2028 0 : if (!md)
2029 : return -ENXIO;
2030 :
2031 0 : mutex_lock(&dm_hash_cells_mutex);
2032 0 : hc = dm_get_mdptr(md);
2033 0 : if (!hc || hc->md != md) {
2034 0 : r = -ENXIO;
2035 0 : goto out;
2036 : }
2037 :
2038 0 : if (name)
2039 0 : strcpy(name, hc->name);
2040 0 : if (uuid)
2041 0 : strcpy(uuid, hc->uuid ? : "");
2042 :
2043 0 : out:
2044 0 : mutex_unlock(&dm_hash_cells_mutex);
2045 :
2046 0 : return r;
2047 : }
2048 : EXPORT_SYMBOL_GPL(dm_copy_name_and_uuid);
2049 :
2050 : /**
2051 : * dm_early_create - create a mapped device in early boot.
2052 : *
2053 : * @dmi: Contains main information of the device mapping to be created.
2054 : * @spec_array: array of pointers to struct dm_target_spec. Describes the
2055 : * mapping table of the device.
2056 : * @target_params_array: array of strings with the parameters to a specific
2057 : * target.
2058 : *
2059 : * Instead of having the struct dm_target_spec and the parameters for every
2060 : * target embedded at the end of struct dm_ioctl (as performed in a normal
2061 : * ioctl), pass them as arguments, so the caller doesn't need to serialize them.
2062 : * The size of the spec_array and target_params_array is given by
2063 : * @dmi->target_count.
2064 : * This function is supposed to be called in early boot, so locking mechanisms
2065 : * to protect against concurrent loads are not required.
2066 : */
2067 0 : int __init dm_early_create(struct dm_ioctl *dmi,
2068 : struct dm_target_spec **spec_array,
2069 : char **target_params_array)
2070 : {
2071 0 : int r, m = DM_ANY_MINOR;
2072 0 : struct dm_table *t, *old_map;
2073 0 : struct mapped_device *md;
2074 0 : unsigned int i;
2075 :
2076 0 : if (!dmi->target_count)
2077 : return -EINVAL;
2078 :
2079 0 : r = check_name(dmi->name);
2080 0 : if (r)
2081 : return r;
2082 :
2083 0 : if (dmi->flags & DM_PERSISTENT_DEV_FLAG)
2084 0 : m = MINOR(huge_decode_dev(dmi->dev));
2085 :
2086 : /* alloc dm device */
2087 0 : r = dm_create(m, &md);
2088 0 : if (r)
2089 : return r;
2090 :
2091 : /* hash insert */
2092 0 : r = dm_hash_insert(dmi->name, *dmi->uuid ? dmi->uuid : NULL, md);
2093 0 : if (r)
2094 0 : goto err_destroy_dm;
2095 :
2096 : /* alloc table */
2097 0 : r = dm_table_create(&t, get_mode(dmi), dmi->target_count, md);
2098 0 : if (r)
2099 0 : goto err_hash_remove;
2100 :
2101 : /* add targets */
2102 0 : for (i = 0; i < dmi->target_count; i++) {
2103 0 : r = dm_table_add_target(t, spec_array[i]->target_type,
2104 0 : (sector_t) spec_array[i]->sector_start,
2105 0 : (sector_t) spec_array[i]->length,
2106 0 : target_params_array[i]);
2107 0 : if (r) {
2108 0 : DMWARN("error adding target to table");
2109 0 : goto err_destroy_table;
2110 : }
2111 : }
2112 :
2113 : /* finish table */
2114 0 : r = dm_table_complete(t);
2115 0 : if (r)
2116 0 : goto err_destroy_table;
2117 :
2118 0 : md->type = dm_table_get_type(t);
2119 : /* setup md->queue to reflect md's type (may block) */
2120 0 : r = dm_setup_md_queue(md, t);
2121 0 : if (r) {
2122 0 : DMWARN("unable to set up device queue for new table.");
2123 0 : goto err_destroy_table;
2124 : }
2125 :
2126 : /* Set new map */
2127 0 : dm_suspend(md, 0);
2128 0 : old_map = dm_swap_table(md, t);
2129 0 : if (IS_ERR(old_map)) {
2130 0 : r = PTR_ERR(old_map);
2131 0 : goto err_destroy_table;
2132 : }
2133 0 : set_disk_ro(dm_disk(md), !!(dmi->flags & DM_READONLY_FLAG));
2134 :
2135 : /* resume device */
2136 0 : r = dm_resume(md);
2137 0 : if (r)
2138 0 : goto err_destroy_table;
2139 :
2140 0 : DMINFO("%s (%s) is ready", md->disk->disk_name, dmi->name);
2141 0 : dm_put(md);
2142 0 : return 0;
2143 :
2144 0 : err_destroy_table:
2145 0 : dm_table_destroy(t);
2146 0 : err_hash_remove:
2147 0 : (void) __hash_remove(__get_name_cell(dmi->name));
2148 : /* release reference from __get_name_cell */
2149 0 : dm_put(md);
2150 0 : err_destroy_dm:
2151 0 : dm_put(md);
2152 0 : dm_destroy(md);
2153 0 : return r;
2154 : }
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