blob: 6d12775a1061059e483fdbeab3bf7b6ccbe53011 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -07003 * Copyright (C) 2004 - 2006 Red Hat, Inc. All rights reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
5 * This file is released under the GPL.
6 */
7
8#include "dm.h"
9
10#include <linux/module.h>
11#include <linux/vmalloc.h>
12#include <linux/miscdevice.h>
13#include <linux/init.h>
14#include <linux/wait.h>
15#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/dm-ioctl.h>
Darrick J. Wong3ac51e72006-03-27 01:17:54 -080017#include <linux/hdreg.h>
Milan Broz76c072b2008-02-08 02:09:56 +000018#include <linux/compat.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019
20#include <asm/uaccess.h>
21
Alasdair G Kergon72d94862006-06-26 00:27:35 -070022#define DM_MSG_PREFIX "ioctl"
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#define DM_DRIVER_EMAIL "dm-devel@redhat.com"
24
25/*-----------------------------------------------------------------
26 * The ioctl interface needs to be able to look up devices by
27 * name or uuid.
28 *---------------------------------------------------------------*/
29struct hash_cell {
30 struct list_head name_list;
31 struct list_head uuid_list;
32
33 char *name;
34 char *uuid;
35 struct mapped_device *md;
36 struct dm_table *new_map;
37};
38
39struct vers_iter {
40 size_t param_size;
41 struct dm_target_versions *vers, *old_vers;
42 char *end;
43 uint32_t flags;
44};
45
46
47#define NUM_BUCKETS 64
48#define MASK_BUCKETS (NUM_BUCKETS - 1)
49static struct list_head _name_buckets[NUM_BUCKETS];
50static struct list_head _uuid_buckets[NUM_BUCKETS];
51
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -070052static void dm_hash_remove_all(int keep_open_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
54/*
55 * Guards access to both hash tables.
56 */
57static DECLARE_RWSEM(_hash_lock);
58
Mikulas Patocka60769052009-12-10 23:51:52 +000059/*
60 * Protects use of mdptr to obtain hash cell name and uuid from mapped device.
61 */
62static DEFINE_MUTEX(dm_hash_cells_mutex);
63
Linus Torvalds1da177e2005-04-16 15:20:36 -070064static void init_buckets(struct list_head *buckets)
65{
66 unsigned int i;
67
68 for (i = 0; i < NUM_BUCKETS; i++)
69 INIT_LIST_HEAD(buckets + i);
70}
71
72static int dm_hash_init(void)
73{
74 init_buckets(_name_buckets);
75 init_buckets(_uuid_buckets);
Linus Torvalds1da177e2005-04-16 15:20:36 -070076 return 0;
77}
78
79static void dm_hash_exit(void)
80{
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -070081 dm_hash_remove_all(0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082}
83
84/*-----------------------------------------------------------------
85 * Hash function:
86 * We're not really concerned with the str hash function being
87 * fast since it's only used by the ioctl interface.
88 *---------------------------------------------------------------*/
89static unsigned int hash_str(const char *str)
90{
91 const unsigned int hash_mult = 2654435387U;
92 unsigned int h = 0;
93
94 while (*str)
95 h = (h + (unsigned int) *str++) * hash_mult;
96
97 return h & MASK_BUCKETS;
98}
99
100/*-----------------------------------------------------------------
101 * Code for looking up a device by name
102 *---------------------------------------------------------------*/
103static struct hash_cell *__get_name_cell(const char *str)
104{
105 struct hash_cell *hc;
106 unsigned int h = hash_str(str);
107
108 list_for_each_entry (hc, _name_buckets + h, name_list)
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700109 if (!strcmp(hc->name, str)) {
110 dm_get(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 return hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700112 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113
114 return NULL;
115}
116
117static struct hash_cell *__get_uuid_cell(const char *str)
118{
119 struct hash_cell *hc;
120 unsigned int h = hash_str(str);
121
122 list_for_each_entry (hc, _uuid_buckets + h, uuid_list)
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700123 if (!strcmp(hc->uuid, str)) {
124 dm_get(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 return hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700126 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127
128 return NULL;
129}
130
131/*-----------------------------------------------------------------
132 * Inserting, removing and renaming a device.
133 *---------------------------------------------------------------*/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134static struct hash_cell *alloc_cell(const char *name, const char *uuid,
135 struct mapped_device *md)
136{
137 struct hash_cell *hc;
138
139 hc = kmalloc(sizeof(*hc), GFP_KERNEL);
140 if (!hc)
141 return NULL;
142
Paulo Marques543537b2005-06-23 00:09:02 -0700143 hc->name = kstrdup(name, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 if (!hc->name) {
145 kfree(hc);
146 return NULL;
147 }
148
149 if (!uuid)
150 hc->uuid = NULL;
151
152 else {
Paulo Marques543537b2005-06-23 00:09:02 -0700153 hc->uuid = kstrdup(uuid, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 if (!hc->uuid) {
155 kfree(hc->name);
156 kfree(hc);
157 return NULL;
158 }
159 }
160
161 INIT_LIST_HEAD(&hc->name_list);
162 INIT_LIST_HEAD(&hc->uuid_list);
163 hc->md = md;
164 hc->new_map = NULL;
165 return hc;
166}
167
168static void free_cell(struct hash_cell *hc)
169{
170 if (hc) {
171 kfree(hc->name);
172 kfree(hc->uuid);
173 kfree(hc);
174 }
175}
176
177/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 * The kdev_t and uuid of a device can never change once it is
179 * initially inserted.
180 */
181static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
182{
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700183 struct hash_cell *cell, *hc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184
185 /*
186 * Allocate the new cells.
187 */
188 cell = alloc_cell(name, uuid, md);
189 if (!cell)
190 return -ENOMEM;
191
192 /*
193 * Insert the cell into both hash tables.
194 */
195 down_write(&_hash_lock);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700196 hc = __get_name_cell(name);
197 if (hc) {
198 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 goto bad;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700200 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
202 list_add(&cell->name_list, _name_buckets + hash_str(name));
203
204 if (uuid) {
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700205 hc = __get_uuid_cell(uuid);
206 if (hc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 list_del(&cell->name_list);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700208 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 goto bad;
210 }
211 list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
212 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 dm_get(md);
Mikulas Patocka60769052009-12-10 23:51:52 +0000214 mutex_lock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 dm_set_mdptr(md, cell);
Mikulas Patocka60769052009-12-10 23:51:52 +0000216 mutex_unlock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 up_write(&_hash_lock);
218
219 return 0;
220
221 bad:
222 up_write(&_hash_lock);
223 free_cell(cell);
224 return -EBUSY;
225}
226
227static void __hash_remove(struct hash_cell *hc)
228{
goggin, edward269fd2a2005-09-27 21:45:44 -0700229 struct dm_table *table;
230
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 /* remove from the dev hash */
232 list_del(&hc->uuid_list);
233 list_del(&hc->name_list);
Mikulas Patocka60769052009-12-10 23:51:52 +0000234 mutex_lock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 dm_set_mdptr(hc->md, NULL);
Mikulas Patocka60769052009-12-10 23:51:52 +0000236 mutex_unlock(&dm_hash_cells_mutex);
goggin, edward269fd2a2005-09-27 21:45:44 -0700237
Alasdair G Kergon7c666412009-12-10 23:52:19 +0000238 table = dm_get_live_table(hc->md);
goggin, edward269fd2a2005-09-27 21:45:44 -0700239 if (table) {
240 dm_table_event(table);
241 dm_table_put(table);
242 }
243
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 if (hc->new_map)
Mikulas Patockad5816872009-01-06 03:05:10 +0000245 dm_table_destroy(hc->new_map);
Mike Anderson1134e5a2006-03-27 01:17:54 -0800246 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 free_cell(hc);
248}
249
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700250static void dm_hash_remove_all(int keep_open_devices)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251{
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100252 int i, dev_skipped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 struct hash_cell *hc;
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100254 struct mapped_device *md;
255
256retry:
257 dev_skipped = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258
259 down_write(&_hash_lock);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700260
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 for (i = 0; i < NUM_BUCKETS; i++) {
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100262 list_for_each_entry(hc, _name_buckets + i, name_list) {
263 md = hc->md;
264 dm_get(md);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700265
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100266 if (keep_open_devices && dm_lock_for_deletion(md)) {
267 dm_put(md);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700268 dev_skipped++;
269 continue;
270 }
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100271
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 __hash_remove(hc);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100273
274 up_write(&_hash_lock);
275
276 dm_put(md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100277 if (likely(keep_open_devices))
278 dm_destroy(md);
279 else
280 dm_destroy_immediate(md);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100281
282 /*
283 * Some mapped devices may be using other mapped
284 * devices, so repeat until we make no further
285 * progress. If a new mapped device is created
286 * here it will also get removed.
287 */
288 goto retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 }
290 }
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700291
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 up_write(&_hash_lock);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100293
294 if (dev_skipped)
295 DMWARN("remove_all left %d open device(s)", dev_skipped);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296}
297
Peter Jones84c89552011-01-13 19:59:47 +0000298/*
299 * Set the uuid of a hash_cell that isn't already set.
300 */
301static void __set_cell_uuid(struct hash_cell *hc, char *new_uuid)
302{
303 mutex_lock(&dm_hash_cells_mutex);
304 hc->uuid = new_uuid;
305 mutex_unlock(&dm_hash_cells_mutex);
306
307 list_add(&hc->uuid_list, _uuid_buckets + hash_str(new_uuid));
308}
309
310/*
311 * Changes the name of a hash_cell and returns the old name for
312 * the caller to free.
313 */
314static char *__change_cell_name(struct hash_cell *hc, char *new_name)
315{
316 char *old_name;
317
318 /*
319 * Rename and move the name cell.
320 */
321 list_del(&hc->name_list);
322 old_name = hc->name;
323
324 mutex_lock(&dm_hash_cells_mutex);
325 hc->name = new_name;
326 mutex_unlock(&dm_hash_cells_mutex);
327
328 list_add(&hc->name_list, _name_buckets + hash_str(new_name));
329
330 return old_name;
331}
332
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100333static struct mapped_device *dm_hash_rename(struct dm_ioctl *param,
334 const char *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335{
Peter Jones84c89552011-01-13 19:59:47 +0000336 char *new_data, *old_name = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 struct hash_cell *hc;
goggin, edward81f17772006-01-06 00:20:01 -0800338 struct dm_table *table;
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100339 struct mapped_device *md;
Peter Jones84c89552011-01-13 19:59:47 +0000340 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341
342 /*
343 * duplicate new.
344 */
Peter Jones84c89552011-01-13 19:59:47 +0000345 new_data = kstrdup(new, GFP_KERNEL);
346 if (!new_data)
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100347 return ERR_PTR(-ENOMEM);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348
349 down_write(&_hash_lock);
350
351 /*
352 * Is new free ?
353 */
Peter Jones84c89552011-01-13 19:59:47 +0000354 if (change_uuid)
355 hc = __get_uuid_cell(new);
356 else
357 hc = __get_name_cell(new);
358
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 if (hc) {
Peter Jones84c89552011-01-13 19:59:47 +0000360 DMWARN("Unable to change %s on mapped device %s to one that "
361 "already exists: %s",
362 change_uuid ? "uuid" : "name",
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100363 param->name, new);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700364 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 up_write(&_hash_lock);
Peter Jones84c89552011-01-13 19:59:47 +0000366 kfree(new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100367 return ERR_PTR(-EBUSY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 }
369
370 /*
371 * Is there such a device as 'old' ?
372 */
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100373 hc = __get_name_cell(param->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 if (!hc) {
Peter Jones84c89552011-01-13 19:59:47 +0000375 DMWARN("Unable to rename non-existent device, %s to %s%s",
376 param->name, change_uuid ? "uuid " : "", new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 up_write(&_hash_lock);
Peter Jones84c89552011-01-13 19:59:47 +0000378 kfree(new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100379 return ERR_PTR(-ENXIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700380 }
381
382 /*
Peter Jones84c89552011-01-13 19:59:47 +0000383 * Does this device already have a uuid?
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 */
Peter Jones84c89552011-01-13 19:59:47 +0000385 if (change_uuid && hc->uuid) {
386 DMWARN("Unable to change uuid of mapped device %s to %s "
387 "because uuid is already set to %s",
388 param->name, new, hc->uuid);
389 dm_put(hc->md);
390 up_write(&_hash_lock);
391 kfree(new_data);
392 return ERR_PTR(-EINVAL);
393 }
394
395 if (change_uuid)
396 __set_cell_uuid(hc, new_data);
397 else
398 old_name = __change_cell_name(hc, new_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399
goggin, edward81f17772006-01-06 00:20:01 -0800400 /*
401 * Wake up any dm event waiters.
402 */
Alasdair G Kergon7c666412009-12-10 23:52:19 +0000403 table = dm_get_live_table(hc->md);
goggin, edward81f17772006-01-06 00:20:01 -0800404 if (table) {
405 dm_table_event(table);
406 dm_table_put(table);
407 }
408
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100409 if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, param->event_nr))
410 param->flags |= DM_UEVENT_GENERATED_FLAG;
Alasdair G Kergon69267a32007-12-13 14:15:57 +0000411
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100412 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 up_write(&_hash_lock);
414 kfree(old_name);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100415
416 return md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417}
418
419/*-----------------------------------------------------------------
420 * Implementation of the ioctl commands
421 *---------------------------------------------------------------*/
422/*
423 * All the ioctl commands get dispatched to functions with this
424 * prototype.
425 */
426typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size);
427
428static int remove_all(struct dm_ioctl *param, size_t param_size)
429{
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700430 dm_hash_remove_all(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 param->data_size = 0;
432 return 0;
433}
434
435/*
436 * Round up the ptr to an 8-byte boundary.
437 */
438#define ALIGN_MASK 7
439static inline void *align_ptr(void *ptr)
440{
441 return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK);
442}
443
444/*
445 * Retrieves the data payload buffer from an already allocated
446 * struct dm_ioctl.
447 */
448static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
449 size_t *len)
450{
451 param->data_start = align_ptr(param + 1) - (void *) param;
452
453 if (param->data_start < param_size)
454 *len = param_size - param->data_start;
455 else
456 *len = 0;
457
458 return ((void *) param) + param->data_start;
459}
460
461static int list_devices(struct dm_ioctl *param, size_t param_size)
462{
463 unsigned int i;
464 struct hash_cell *hc;
465 size_t len, needed = 0;
466 struct gendisk *disk;
467 struct dm_name_list *nl, *old_nl = NULL;
468
469 down_write(&_hash_lock);
470
471 /*
472 * Loop through all the devices working out how much
473 * space we need.
474 */
475 for (i = 0; i < NUM_BUCKETS; i++) {
476 list_for_each_entry (hc, _name_buckets + i, name_list) {
477 needed += sizeof(struct dm_name_list);
478 needed += strlen(hc->name) + 1;
479 needed += ALIGN_MASK;
480 }
481 }
482
483 /*
484 * Grab our output buffer.
485 */
486 nl = get_result_buffer(param, param_size, &len);
487 if (len < needed) {
488 param->flags |= DM_BUFFER_FULL_FLAG;
489 goto out;
490 }
491 param->data_size = param->data_start + needed;
492
493 nl->dev = 0; /* Flags no data */
494
495 /*
496 * Now loop through filling out the names.
497 */
498 for (i = 0; i < NUM_BUCKETS; i++) {
499 list_for_each_entry (hc, _name_buckets + i, name_list) {
500 if (old_nl)
501 old_nl->next = (uint32_t) ((void *) nl -
502 (void *) old_nl);
503 disk = dm_disk(hc->md);
Tejun Heof331c022008-09-03 09:01:48 +0200504 nl->dev = huge_encode_dev(disk_devt(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505 nl->next = 0;
506 strcpy(nl->name, hc->name);
507
508 old_nl = nl;
509 nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1);
510 }
511 }
512
513 out:
514 up_write(&_hash_lock);
515 return 0;
516}
517
518static void list_version_get_needed(struct target_type *tt, void *needed_param)
519{
520 size_t *needed = needed_param;
521
Alasdair G Kergonc4cc6632005-11-21 21:32:33 -0800522 *needed += sizeof(struct dm_target_versions);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 *needed += strlen(tt->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 *needed += ALIGN_MASK;
525}
526
527static void list_version_get_info(struct target_type *tt, void *param)
528{
529 struct vers_iter *info = param;
530
531 /* Check space - it might have changed since the first iteration */
532 if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 >
533 info->end) {
534
535 info->flags = DM_BUFFER_FULL_FLAG;
536 return;
537 }
538
539 if (info->old_vers)
540 info->old_vers->next = (uint32_t) ((void *)info->vers -
541 (void *)info->old_vers);
542 info->vers->version[0] = tt->version[0];
543 info->vers->version[1] = tt->version[1];
544 info->vers->version[2] = tt->version[2];
545 info->vers->next = 0;
546 strcpy(info->vers->name, tt->name);
547
548 info->old_vers = info->vers;
549 info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
550}
551
552static int list_versions(struct dm_ioctl *param, size_t param_size)
553{
554 size_t len, needed = 0;
555 struct dm_target_versions *vers;
556 struct vers_iter iter_info;
557
558 /*
559 * Loop through all the devices working out how much
560 * space we need.
561 */
562 dm_target_iterate(list_version_get_needed, &needed);
563
564 /*
565 * Grab our output buffer.
566 */
567 vers = get_result_buffer(param, param_size, &len);
568 if (len < needed) {
569 param->flags |= DM_BUFFER_FULL_FLAG;
570 goto out;
571 }
572 param->data_size = param->data_start + needed;
573
574 iter_info.param_size = param_size;
575 iter_info.old_vers = NULL;
576 iter_info.vers = vers;
577 iter_info.flags = 0;
578 iter_info.end = (char *)vers+len;
579
580 /*
581 * Now loop through filling out the names & versions.
582 */
583 dm_target_iterate(list_version_get_info, &iter_info);
584 param->flags |= iter_info.flags;
585
586 out:
587 return 0;
588}
589
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590static int check_name(const char *name)
591{
592 if (strchr(name, '/')) {
593 DMWARN("invalid device name");
594 return -EINVAL;
595 }
596
597 return 0;
598}
599
600/*
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000601 * On successful return, the caller must not attempt to acquire
602 * _hash_lock without first calling dm_table_put, because dm_table_destroy
603 * waits for this dm_table_put and could be called under this lock.
604 */
605static struct dm_table *dm_get_inactive_table(struct mapped_device *md)
606{
607 struct hash_cell *hc;
608 struct dm_table *table = NULL;
609
610 down_read(&_hash_lock);
611 hc = dm_get_mdptr(md);
612 if (!hc || hc->md != md) {
613 DMWARN("device has been removed from the dev hash table.");
614 goto out;
615 }
616
617 table = hc->new_map;
618 if (table)
619 dm_table_get(table);
620
621out:
622 up_read(&_hash_lock);
623
624 return table;
625}
626
627static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md,
628 struct dm_ioctl *param)
629{
630 return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ?
631 dm_get_inactive_table(md) : dm_get_live_table(md);
632}
633
634/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 * Fills in a dm_ioctl structure, ready for sending back to
636 * userland.
637 */
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100638static void __dev_status(struct mapped_device *md, struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639{
640 struct gendisk *disk = dm_disk(md);
641 struct dm_table *table;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642
643 param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
644 DM_ACTIVE_PRESENT_FLAG);
645
Kiyoshi Ueda4f186f82009-12-10 23:52:26 +0000646 if (dm_suspended_md(md))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 param->flags |= DM_SUSPEND_FLAG;
648
Tejun Heof331c022008-09-03 09:01:48 +0200649 param->dev = huge_encode_dev(disk_devt(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700651 /*
652 * Yes, this will be out of date by the time it gets back
653 * to userland, but it is still very useful for
654 * debugging.
655 */
656 param->open_count = dm_open_count(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 param->event_nr = dm_get_event_nr(md);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000659 param->target_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660
Alasdair G Kergon7c666412009-12-10 23:52:19 +0000661 table = dm_get_live_table(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700662 if (table) {
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000663 if (!(param->flags & DM_QUERY_INACTIVE_TABLE_FLAG)) {
664 if (get_disk_ro(disk))
665 param->flags |= DM_READONLY_FLAG;
666 param->target_count = dm_table_get_num_targets(table);
667 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 dm_table_put(table);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000669
670 param->flags |= DM_ACTIVE_PRESENT_FLAG;
671 }
672
673 if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) {
674 table = dm_get_inactive_table(md);
675 if (table) {
676 if (!(dm_table_get_mode(table) & FMODE_WRITE))
677 param->flags |= DM_READONLY_FLAG;
678 param->target_count = dm_table_get_num_targets(table);
679 dm_table_put(table);
680 }
681 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682}
683
684static int dev_create(struct dm_ioctl *param, size_t param_size)
685{
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700686 int r, m = DM_ANY_MINOR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 struct mapped_device *md;
688
689 r = check_name(param->name);
690 if (r)
691 return r;
692
693 if (param->flags & DM_PERSISTENT_DEV_FLAG)
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700694 m = MINOR(huge_decode_dev(param->dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700696 r = dm_create(m, &md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 if (r)
698 return r;
699
700 r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100701 if (r) {
702 dm_put(md);
703 dm_destroy(md);
704 return r;
705 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706
707 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
708
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100709 __dev_status(md, param);
710
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 dm_put(md);
712
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100713 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714}
715
716/*
717 * Always use UUID for lookups if it's present, otherwise use name or dev.
718 */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800719static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720{
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800721 struct mapped_device *md;
722 void *mdptr = NULL;
723
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 if (*param->uuid)
725 return __get_uuid_cell(param->uuid);
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800726
727 if (*param->name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 return __get_name_cell(param->name);
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800729
730 md = dm_get_md(huge_decode_dev(param->dev));
Alasdair G Kergonbfc5ecd2006-11-08 17:44:42 -0800731 if (!md)
732 goto out;
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800733
Alasdair G Kergonbfc5ecd2006-11-08 17:44:42 -0800734 mdptr = dm_get_mdptr(md);
735 if (!mdptr)
736 dm_put(md);
737
738out:
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800739 return mdptr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740}
741
Arjan van de Ven858119e2006-01-14 13:20:43 -0800742static struct mapped_device *find_device(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743{
744 struct hash_cell *hc;
745 struct mapped_device *md = NULL;
746
747 down_read(&_hash_lock);
748 hc = __find_device_hash_cell(param);
749 if (hc) {
750 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751
752 /*
753 * Sneakily write in both the name and the uuid
754 * while we have the cell.
755 */
Roel Kluina518b862009-12-10 23:52:07 +0000756 strlcpy(param->name, hc->name, sizeof(param->name));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 if (hc->uuid)
Roel Kluina518b862009-12-10 23:52:07 +0000758 strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759 else
760 param->uuid[0] = '\0';
761
762 if (hc->new_map)
763 param->flags |= DM_INACTIVE_PRESENT_FLAG;
764 else
765 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
766 }
767 up_read(&_hash_lock);
768
769 return md;
770}
771
772static int dev_remove(struct dm_ioctl *param, size_t param_size)
773{
774 struct hash_cell *hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700775 struct mapped_device *md;
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700776 int r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777
778 down_write(&_hash_lock);
779 hc = __find_device_hash_cell(param);
780
781 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +0000782 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783 up_write(&_hash_lock);
784 return -ENXIO;
785 }
786
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700787 md = hc->md;
788
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700789 /*
790 * Ensure the device is not open and nothing further can open it.
791 */
792 r = dm_lock_for_deletion(md);
793 if (r) {
Milan Broz810b4922011-01-13 19:59:55 +0000794 DMDEBUG_LIMIT("unable to remove open device %s", hc->name);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700795 up_write(&_hash_lock);
796 dm_put(md);
797 return r;
798 }
799
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 __hash_remove(hc);
801 up_write(&_hash_lock);
Milan Broz60935eb2009-06-22 10:12:30 +0100802
Peter Rajnoha3abf85b2010-03-06 02:32:31 +0000803 if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr))
804 param->flags |= DM_UEVENT_GENERATED_FLAG;
Milan Broz60935eb2009-06-22 10:12:30 +0100805
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700806 dm_put(md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100807 dm_destroy(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 return 0;
809}
810
811/*
812 * Check a string doesn't overrun the chunk of
813 * memory we copied from userland.
814 */
815static int invalid_str(char *str, void *end)
816{
817 while ((void *) str < end)
818 if (!*str++)
819 return 0;
820
821 return -EINVAL;
822}
823
824static int dev_rename(struct dm_ioctl *param, size_t param_size)
825{
826 int r;
Peter Jones84c89552011-01-13 19:59:47 +0000827 char *new_data = (char *) param + param->data_start;
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100828 struct mapped_device *md;
Peter Jones84c89552011-01-13 19:59:47 +0000829 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830
Peter Jones84c89552011-01-13 19:59:47 +0000831 if (new_data < param->data ||
832 invalid_str(new_data, (void *) param + param_size) ||
833 strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) {
834 DMWARN("Invalid new mapped device name or uuid string supplied.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 return -EINVAL;
836 }
837
Peter Jones84c89552011-01-13 19:59:47 +0000838 if (!change_uuid) {
839 r = check_name(new_data);
840 if (r)
841 return r;
842 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843
Peter Jones84c89552011-01-13 19:59:47 +0000844 md = dm_hash_rename(param, new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100845 if (IS_ERR(md))
846 return PTR_ERR(md);
Peter Rajnoha3abf85b2010-03-06 02:32:31 +0000847
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100848 __dev_status(md, param);
849 dm_put(md);
850
851 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852}
853
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800854static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
855{
856 int r = -EINVAL, x;
857 struct mapped_device *md;
858 struct hd_geometry geometry;
859 unsigned long indata[4];
860 char *geostr = (char *) param + param->data_start;
861
862 md = find_device(param);
863 if (!md)
864 return -ENXIO;
865
Alasdair G Kergon27238b22008-02-08 02:09:53 +0000866 if (geostr < param->data ||
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800867 invalid_str(geostr, (void *) param + param_size)) {
868 DMWARN("Invalid geometry supplied.");
869 goto out;
870 }
871
872 x = sscanf(geostr, "%lu %lu %lu %lu", indata,
873 indata + 1, indata + 2, indata + 3);
874
875 if (x != 4) {
876 DMWARN("Unable to interpret geometry settings.");
877 goto out;
878 }
879
880 if (indata[0] > 65535 || indata[1] > 255 ||
881 indata[2] > 255 || indata[3] > ULONG_MAX) {
882 DMWARN("Geometry exceeds range limits.");
883 goto out;
884 }
885
886 geometry.cylinders = indata[0];
887 geometry.heads = indata[1];
888 geometry.sectors = indata[2];
889 geometry.start = indata[3];
890
891 r = dm_set_geometry(md, &geometry);
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800892
893 param->data_size = 0;
894
895out:
896 dm_put(md);
897 return r;
898}
899
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900static int do_suspend(struct dm_ioctl *param)
901{
902 int r = 0;
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800903 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904 struct mapped_device *md;
905
906 md = find_device(param);
907 if (!md)
908 return -ENXIO;
909
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800910 if (param->flags & DM_SKIP_LOCKFS_FLAG)
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800911 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
Kiyoshi Ueda81fdb092006-12-08 02:41:07 -0800912 if (param->flags & DM_NOFLUSH_FLAG)
913 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800914
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100915 if (!dm_suspended_md(md)) {
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800916 r = dm_suspend(md, suspend_flags);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100917 if (r)
918 goto out;
919 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100921 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100923out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100925
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 return r;
927}
928
929static int do_resume(struct dm_ioctl *param)
930{
931 int r = 0;
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800932 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 struct hash_cell *hc;
934 struct mapped_device *md;
Alasdair G Kergon042d2a92009-12-10 23:52:24 +0000935 struct dm_table *new_map, *old_map = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936
937 down_write(&_hash_lock);
938
939 hc = __find_device_hash_cell(param);
940 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +0000941 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942 up_write(&_hash_lock);
943 return -ENXIO;
944 }
945
946 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947
948 new_map = hc->new_map;
949 hc->new_map = NULL;
950 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
951
952 up_write(&_hash_lock);
953
954 /* Do we need to load a new map ? */
955 if (new_map) {
956 /* Suspend if it isn't already suspended */
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800957 if (param->flags & DM_SKIP_LOCKFS_FLAG)
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800958 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
Kiyoshi Ueda81fdb092006-12-08 02:41:07 -0800959 if (param->flags & DM_NOFLUSH_FLAG)
960 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
Kiyoshi Ueda4f186f82009-12-10 23:52:26 +0000961 if (!dm_suspended_md(md))
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800962 dm_suspend(md, suspend_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963
Alasdair G Kergon042d2a92009-12-10 23:52:24 +0000964 old_map = dm_swap_table(md, new_map);
965 if (IS_ERR(old_map)) {
Mikulas Patockad5816872009-01-06 03:05:10 +0000966 dm_table_destroy(new_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 dm_put(md);
Alasdair G Kergon042d2a92009-12-10 23:52:24 +0000968 return PTR_ERR(old_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 }
970
971 if (dm_table_get_mode(new_map) & FMODE_WRITE)
972 set_disk_ro(dm_disk(md), 0);
973 else
974 set_disk_ro(dm_disk(md), 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 }
976
Mike Snitzer0f3649a2010-03-06 02:32:24 +0000977 if (dm_suspended_md(md)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 r = dm_resume(md);
Peter Rajnoha3abf85b2010-03-06 02:32:31 +0000979 if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
980 param->flags |= DM_UEVENT_GENERATED_FLAG;
Mike Snitzer0f3649a2010-03-06 02:32:24 +0000981 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700982
Alasdair G Kergon042d2a92009-12-10 23:52:24 +0000983 if (old_map)
984 dm_table_destroy(old_map);
Milan Broz60935eb2009-06-22 10:12:30 +0100985
Mike Snitzer0f3649a2010-03-06 02:32:24 +0000986 if (!r)
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100987 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988
989 dm_put(md);
990 return r;
991}
992
993/*
994 * Set or unset the suspension state of a device.
995 * If the device already is in the requested state we just return its status.
996 */
997static int dev_suspend(struct dm_ioctl *param, size_t param_size)
998{
999 if (param->flags & DM_SUSPEND_FLAG)
1000 return do_suspend(param);
1001
1002 return do_resume(param);
1003}
1004
1005/*
1006 * Copies device info back to user space, used by
1007 * the create and info ioctls.
1008 */
1009static int dev_status(struct dm_ioctl *param, size_t param_size)
1010{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 struct mapped_device *md;
1012
1013 md = find_device(param);
1014 if (!md)
1015 return -ENXIO;
1016
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001017 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001018 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001019
1020 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021}
1022
1023/*
1024 * Build up the status struct for each target
1025 */
1026static void retrieve_status(struct dm_table *table,
1027 struct dm_ioctl *param, size_t param_size)
1028{
1029 unsigned int i, num_targets;
1030 struct dm_target_spec *spec;
1031 char *outbuf, *outptr;
1032 status_type_t type;
1033 size_t remaining, len, used = 0;
1034
1035 outptr = outbuf = get_result_buffer(param, param_size, &len);
1036
1037 if (param->flags & DM_STATUS_TABLE_FLAG)
1038 type = STATUSTYPE_TABLE;
1039 else
1040 type = STATUSTYPE_INFO;
1041
1042 /* Get all the target info */
1043 num_targets = dm_table_get_num_targets(table);
1044 for (i = 0; i < num_targets; i++) {
1045 struct dm_target *ti = dm_table_get_target(table, i);
1046
1047 remaining = len - (outptr - outbuf);
1048 if (remaining <= sizeof(struct dm_target_spec)) {
1049 param->flags |= DM_BUFFER_FULL_FLAG;
1050 break;
1051 }
1052
1053 spec = (struct dm_target_spec *) outptr;
1054
1055 spec->status = 0;
1056 spec->sector_start = ti->begin;
1057 spec->length = ti->len;
1058 strncpy(spec->target_type, ti->type->name,
1059 sizeof(spec->target_type));
1060
1061 outptr += sizeof(struct dm_target_spec);
1062 remaining = len - (outptr - outbuf);
1063 if (remaining <= 0) {
1064 param->flags |= DM_BUFFER_FULL_FLAG;
1065 break;
1066 }
1067
1068 /* Get the status/table string from the target driver */
1069 if (ti->type->status) {
1070 if (ti->type->status(ti, type, outptr, remaining)) {
1071 param->flags |= DM_BUFFER_FULL_FLAG;
1072 break;
1073 }
1074 } else
1075 outptr[0] = '\0';
1076
1077 outptr += strlen(outptr) + 1;
1078 used = param->data_start + (outptr - outbuf);
1079
1080 outptr = align_ptr(outptr);
1081 spec->next = outptr - outbuf;
1082 }
1083
1084 if (used)
1085 param->data_size = used;
1086
1087 param->target_count = num_targets;
1088}
1089
1090/*
1091 * Wait for a device to report an event
1092 */
1093static int dev_wait(struct dm_ioctl *param, size_t param_size)
1094{
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001095 int r = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 struct mapped_device *md;
1097 struct dm_table *table;
1098
1099 md = find_device(param);
1100 if (!md)
1101 return -ENXIO;
1102
1103 /*
1104 * Wait for a notification event
1105 */
1106 if (dm_wait_event(md, param->event_nr)) {
1107 r = -ERESTARTSYS;
1108 goto out;
1109 }
1110
1111 /*
1112 * The userland program is going to want to know what
1113 * changed to trigger the event, so we may as well tell
1114 * him and save an ioctl.
1115 */
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001116 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +00001118 table = dm_get_live_or_inactive_table(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119 if (table) {
1120 retrieve_status(table, param, param_size);
1121 dm_table_put(table);
1122 }
1123
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001124out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001125 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001126
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127 return r;
1128}
1129
Al Viroaeb5d722008-09-02 15:28:45 -04001130static inline fmode_t get_mode(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131{
Al Viroaeb5d722008-09-02 15:28:45 -04001132 fmode_t mode = FMODE_READ | FMODE_WRITE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001133
1134 if (param->flags & DM_READONLY_FLAG)
1135 mode = FMODE_READ;
1136
1137 return mode;
1138}
1139
1140static int next_target(struct dm_target_spec *last, uint32_t next, void *end,
1141 struct dm_target_spec **spec, char **target_params)
1142{
1143 *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
1144 *target_params = (char *) (*spec + 1);
1145
1146 if (*spec < (last + 1))
1147 return -EINVAL;
1148
1149 return invalid_str(*target_params, end);
1150}
1151
1152static int populate_table(struct dm_table *table,
1153 struct dm_ioctl *param, size_t param_size)
1154{
1155 int r;
1156 unsigned int i = 0;
1157 struct dm_target_spec *spec = (struct dm_target_spec *) param;
1158 uint32_t next = param->data_start;
1159 void *end = (void *) param + param_size;
1160 char *target_params;
1161
1162 if (!param->target_count) {
1163 DMWARN("populate_table: no targets specified");
1164 return -EINVAL;
1165 }
1166
1167 for (i = 0; i < param->target_count; i++) {
1168
1169 r = next_target(spec, next, end, &spec, &target_params);
1170 if (r) {
1171 DMWARN("unable to find target");
1172 return r;
1173 }
1174
1175 r = dm_table_add_target(table, spec->target_type,
1176 (sector_t) spec->sector_start,
1177 (sector_t) spec->length,
1178 target_params);
1179 if (r) {
1180 DMWARN("error adding target to table");
1181 return r;
1182 }
1183
1184 next = spec->next;
1185 }
1186
1187 return dm_table_complete(table);
1188}
1189
1190static int table_load(struct dm_ioctl *param, size_t param_size)
1191{
1192 int r;
1193 struct hash_cell *hc;
1194 struct dm_table *t;
Mike Anderson1134e5a2006-03-27 01:17:54 -08001195 struct mapped_device *md;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001196
Mike Anderson1134e5a2006-03-27 01:17:54 -08001197 md = find_device(param);
1198 if (!md)
1199 return -ENXIO;
1200
1201 r = dm_table_create(&t, get_mode(param), param->target_count, md);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001202 if (r)
Mike Anderson1134e5a2006-03-27 01:17:54 -08001203 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204
1205 r = populate_table(t, param, param_size);
1206 if (r) {
Mikulas Patockaf80a5572009-03-16 17:44:26 +00001207 dm_table_destroy(t);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001208 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001209 }
1210
Mike Snitzer4a0b4dd2010-08-12 04:14:02 +01001211 /* Protect md->type and md->queue against concurrent table loads. */
Mike Snitzera5664da2010-08-12 04:14:01 +01001212 dm_lock_md_type(md);
1213 if (dm_get_md_type(md) == DM_TYPE_NONE)
1214 /* Initial table load: acquire type of table. */
1215 dm_set_md_type(md, dm_table_get_type(t));
1216 else if (dm_get_md_type(md) != dm_table_get_type(t)) {
1217 DMWARN("can't change device type after initial table load.");
1218 dm_table_destroy(t);
1219 dm_unlock_md_type(md);
1220 r = -EINVAL;
1221 goto out;
1222 }
Mike Snitzer4a0b4dd2010-08-12 04:14:02 +01001223
1224 /* setup md->queue to reflect md's type (may block) */
1225 r = dm_setup_md_queue(md);
1226 if (r) {
1227 DMWARN("unable to set up device queue for new table.");
1228 dm_table_destroy(t);
1229 dm_unlock_md_type(md);
1230 goto out;
1231 }
Mike Snitzera5664da2010-08-12 04:14:01 +01001232 dm_unlock_md_type(md);
1233
1234 /* stage inactive table */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001235 down_write(&_hash_lock);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001236 hc = dm_get_mdptr(md);
1237 if (!hc || hc->md != md) {
1238 DMWARN("device has been removed from the dev hash table.");
Mikulas Patockaf80a5572009-03-16 17:44:26 +00001239 dm_table_destroy(t);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001240 up_write(&_hash_lock);
1241 r = -ENXIO;
1242 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243 }
1244
1245 if (hc->new_map)
Mikulas Patockad5816872009-01-06 03:05:10 +00001246 dm_table_destroy(hc->new_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001247 hc->new_map = t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248 up_write(&_hash_lock);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001249
1250 param->flags |= DM_INACTIVE_PRESENT_FLAG;
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001251 __dev_status(md, param);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001252
1253out:
1254 dm_put(md);
1255
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256 return r;
1257}
1258
1259static int table_clear(struct dm_ioctl *param, size_t param_size)
1260{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001261 struct hash_cell *hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001262 struct mapped_device *md;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001263
1264 down_write(&_hash_lock);
1265
1266 hc = __find_device_hash_cell(param);
1267 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +00001268 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001269 up_write(&_hash_lock);
1270 return -ENXIO;
1271 }
1272
1273 if (hc->new_map) {
Mikulas Patockad5816872009-01-06 03:05:10 +00001274 dm_table_destroy(hc->new_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275 hc->new_map = NULL;
1276 }
1277
1278 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1279
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001280 __dev_status(hc->md, param);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001281 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001282 up_write(&_hash_lock);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001283 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001284
1285 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286}
1287
1288/*
1289 * Retrieves a list of devices used by a particular dm device.
1290 */
1291static void retrieve_deps(struct dm_table *table,
1292 struct dm_ioctl *param, size_t param_size)
1293{
1294 unsigned int count = 0;
1295 struct list_head *tmp;
1296 size_t len, needed;
Mikulas Patocka82b15192008-10-10 13:37:09 +01001297 struct dm_dev_internal *dd;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298 struct dm_target_deps *deps;
1299
1300 deps = get_result_buffer(param, param_size, &len);
1301
1302 /*
1303 * Count the devices.
1304 */
1305 list_for_each (tmp, dm_table_get_devices(table))
1306 count++;
1307
1308 /*
1309 * Check we have enough space.
1310 */
1311 needed = sizeof(*deps) + (sizeof(*deps->dev) * count);
1312 if (len < needed) {
1313 param->flags |= DM_BUFFER_FULL_FLAG;
1314 return;
1315 }
1316
1317 /*
1318 * Fill in the devices.
1319 */
1320 deps->count = count;
1321 count = 0;
1322 list_for_each_entry (dd, dm_table_get_devices(table), list)
Mikulas Patocka82b15192008-10-10 13:37:09 +01001323 deps->dev[count++] = huge_encode_dev(dd->dm_dev.bdev->bd_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001324
1325 param->data_size = param->data_start + needed;
1326}
1327
1328static int table_deps(struct dm_ioctl *param, size_t param_size)
1329{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001330 struct mapped_device *md;
1331 struct dm_table *table;
1332
1333 md = find_device(param);
1334 if (!md)
1335 return -ENXIO;
1336
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001337 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +00001339 table = dm_get_live_or_inactive_table(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340 if (table) {
1341 retrieve_deps(table, param, param_size);
1342 dm_table_put(table);
1343 }
1344
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001346
1347 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001348}
1349
1350/*
1351 * Return the status of a device as a text string for each
1352 * target.
1353 */
1354static int table_status(struct dm_ioctl *param, size_t param_size)
1355{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356 struct mapped_device *md;
1357 struct dm_table *table;
1358
1359 md = find_device(param);
1360 if (!md)
1361 return -ENXIO;
1362
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001363 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +00001365 table = dm_get_live_or_inactive_table(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366 if (table) {
1367 retrieve_status(table, param, param_size);
1368 dm_table_put(table);
1369 }
1370
Linus Torvalds1da177e2005-04-16 15:20:36 -07001371 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001372
1373 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001374}
1375
1376/*
1377 * Pass a message to the target that's at the supplied device offset.
1378 */
1379static int target_message(struct dm_ioctl *param, size_t param_size)
1380{
1381 int r, argc;
1382 char **argv;
1383 struct mapped_device *md;
1384 struct dm_table *table;
1385 struct dm_target *ti;
1386 struct dm_target_msg *tmsg = (void *) param + param->data_start;
1387
1388 md = find_device(param);
1389 if (!md)
1390 return -ENXIO;
1391
Milan Broz027d50f2007-10-19 22:38:36 +01001392 if (tmsg < (struct dm_target_msg *) param->data ||
Linus Torvalds1da177e2005-04-16 15:20:36 -07001393 invalid_str(tmsg->message, (void *) param + param_size)) {
1394 DMWARN("Invalid target message parameters.");
1395 r = -EINVAL;
1396 goto out;
1397 }
1398
1399 r = dm_split_args(&argc, &argv, tmsg->message);
1400 if (r) {
1401 DMWARN("Failed to split target message parameters");
1402 goto out;
1403 }
1404
Alasdair G Kergon7c666412009-12-10 23:52:19 +00001405 table = dm_get_live_table(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406 if (!table)
1407 goto out_argv;
1408
Mike Andersonc50abeb2009-12-10 23:52:20 +00001409 if (dm_deleting_md(md)) {
1410 r = -ENXIO;
1411 goto out_table;
1412 }
1413
Jun'ichi Nomura512875b2007-12-13 14:15:25 +00001414 ti = dm_table_find_target(table, tmsg->sector);
1415 if (!dm_target_is_valid(ti)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001416 DMWARN("Target message sector outside device.");
1417 r = -EINVAL;
Jun'ichi Nomura512875b2007-12-13 14:15:25 +00001418 } else if (ti->type->message)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001419 r = ti->type->message(ti, argc, argv);
1420 else {
1421 DMWARN("Target type does not support messages");
1422 r = -EINVAL;
1423 }
1424
Mike Andersonc50abeb2009-12-10 23:52:20 +00001425 out_table:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426 dm_table_put(table);
1427 out_argv:
1428 kfree(argv);
1429 out:
1430 param->data_size = 0;
1431 dm_put(md);
1432 return r;
1433}
1434
1435/*-----------------------------------------------------------------
1436 * Implementation of open/close/ioctl on the special char
1437 * device.
1438 *---------------------------------------------------------------*/
1439static ioctl_fn lookup_ioctl(unsigned int cmd)
1440{
1441 static struct {
1442 int cmd;
1443 ioctl_fn fn;
1444 } _ioctls[] = {
1445 {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */
1446 {DM_REMOVE_ALL_CMD, remove_all},
1447 {DM_LIST_DEVICES_CMD, list_devices},
1448
1449 {DM_DEV_CREATE_CMD, dev_create},
1450 {DM_DEV_REMOVE_CMD, dev_remove},
1451 {DM_DEV_RENAME_CMD, dev_rename},
1452 {DM_DEV_SUSPEND_CMD, dev_suspend},
1453 {DM_DEV_STATUS_CMD, dev_status},
1454 {DM_DEV_WAIT_CMD, dev_wait},
1455
1456 {DM_TABLE_LOAD_CMD, table_load},
1457 {DM_TABLE_CLEAR_CMD, table_clear},
1458 {DM_TABLE_DEPS_CMD, table_deps},
1459 {DM_TABLE_STATUS_CMD, table_status},
1460
1461 {DM_LIST_VERSIONS_CMD, list_versions},
1462
Darrick J. Wong3ac51e72006-03-27 01:17:54 -08001463 {DM_TARGET_MSG_CMD, target_message},
1464 {DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001465 };
1466
1467 return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn;
1468}
1469
1470/*
1471 * As well as checking the version compatibility this always
1472 * copies the kernel interface version out.
1473 */
1474static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
1475{
1476 uint32_t version[3];
1477 int r = 0;
1478
1479 if (copy_from_user(version, user->version, sizeof(version)))
1480 return -EFAULT;
1481
1482 if ((DM_VERSION_MAJOR != version[0]) ||
1483 (DM_VERSION_MINOR < version[1])) {
1484 DMWARN("ioctl interface mismatch: "
1485 "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1486 DM_VERSION_MAJOR, DM_VERSION_MINOR,
1487 DM_VERSION_PATCHLEVEL,
1488 version[0], version[1], version[2], cmd);
1489 r = -EINVAL;
1490 }
1491
1492 /*
1493 * Fill in the kernel version.
1494 */
1495 version[0] = DM_VERSION_MAJOR;
1496 version[1] = DM_VERSION_MINOR;
1497 version[2] = DM_VERSION_PATCHLEVEL;
1498 if (copy_to_user(user->version, version, sizeof(version)))
1499 return -EFAULT;
1500
1501 return r;
1502}
1503
1504static void free_params(struct dm_ioctl *param)
1505{
1506 vfree(param);
1507}
1508
1509static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
1510{
1511 struct dm_ioctl tmp, *dmi;
1512
Milan Broz76c072b2008-02-08 02:09:56 +00001513 if (copy_from_user(&tmp, user, sizeof(tmp) - sizeof(tmp.data)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514 return -EFAULT;
1515
Milan Broz76c072b2008-02-08 02:09:56 +00001516 if (tmp.data_size < (sizeof(tmp) - sizeof(tmp.data)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001517 return -EINVAL;
1518
Jesper Juhlbb56acf2007-10-19 22:38:54 +01001519 dmi = vmalloc(tmp.data_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520 if (!dmi)
1521 return -ENOMEM;
1522
1523 if (copy_from_user(dmi, user, tmp.data_size)) {
1524 vfree(dmi);
1525 return -EFAULT;
1526 }
1527
1528 *param = dmi;
1529 return 0;
1530}
1531
1532static int validate_params(uint cmd, struct dm_ioctl *param)
1533{
1534 /* Always clear this flag */
1535 param->flags &= ~DM_BUFFER_FULL_FLAG;
Peter Rajnoha3abf85b2010-03-06 02:32:31 +00001536 param->flags &= ~DM_UEVENT_GENERATED_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001537
1538 /* Ignores parameters */
1539 if (cmd == DM_REMOVE_ALL_CMD ||
1540 cmd == DM_LIST_DEVICES_CMD ||
1541 cmd == DM_LIST_VERSIONS_CMD)
1542 return 0;
1543
1544 if ((cmd == DM_DEV_CREATE_CMD)) {
1545 if (!*param->name) {
1546 DMWARN("name not supplied when creating device");
1547 return -EINVAL;
1548 }
1549 } else if ((*param->uuid && *param->name)) {
1550 DMWARN("only supply one of name or uuid, cmd(%u)", cmd);
1551 return -EINVAL;
1552 }
1553
1554 /* Ensure strings are terminated */
1555 param->name[DM_NAME_LEN - 1] = '\0';
1556 param->uuid[DM_UUID_LEN - 1] = '\0';
1557
1558 return 0;
1559}
1560
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001561static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001562{
1563 int r = 0;
1564 unsigned int cmd;
Andrew Mortona26ffd42008-02-08 02:10:16 +00001565 struct dm_ioctl *uninitialized_var(param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001566 ioctl_fn fn = NULL;
1567 size_t param_size;
1568
1569 /* only root can play with this */
1570 if (!capable(CAP_SYS_ADMIN))
1571 return -EACCES;
1572
1573 if (_IOC_TYPE(command) != DM_IOCTL)
1574 return -ENOTTY;
1575
1576 cmd = _IOC_NR(command);
1577
1578 /*
1579 * Check the interface version passed in. This also
1580 * writes out the kernel's interface version.
1581 */
1582 r = check_version(cmd, user);
1583 if (r)
1584 return r;
1585
1586 /*
1587 * Nothing more to do for the version command.
1588 */
1589 if (cmd == DM_VERSION_CMD)
1590 return 0;
1591
1592 fn = lookup_ioctl(cmd);
1593 if (!fn) {
1594 DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
1595 return -ENOTTY;
1596 }
1597
1598 /*
1599 * Trying to avoid low memory issues when a device is
1600 * suspended.
1601 */
1602 current->flags |= PF_MEMALLOC;
1603
1604 /*
1605 * Copy the parameters into kernel space.
1606 */
1607 r = copy_params(user, &param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608
Alasdair G Kergondab6a422006-02-01 03:04:52 -08001609 current->flags &= ~PF_MEMALLOC;
1610
1611 if (r)
1612 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001613
1614 r = validate_params(cmd, param);
1615 if (r)
1616 goto out;
1617
1618 param_size = param->data_size;
1619 param->data_size = sizeof(*param);
1620 r = fn(param, param_size);
1621
1622 /*
1623 * Copy the results back to userland.
1624 */
1625 if (!r && copy_to_user(user, param, param->data_size))
1626 r = -EFAULT;
1627
1628 out:
1629 free_params(param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001630 return r;
1631}
1632
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001633static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
1634{
1635 return (long)ctl_ioctl(command, (struct dm_ioctl __user *)u);
1636}
1637
Milan Broz76c072b2008-02-08 02:09:56 +00001638#ifdef CONFIG_COMPAT
1639static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
1640{
1641 return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
1642}
1643#else
1644#define dm_compat_ctl_ioctl NULL
1645#endif
1646
Arjan van de Venfa027c22007-02-12 00:55:33 -08001647static const struct file_operations _ctl_fops = {
Arnd Bergmann402ab352010-08-12 04:13:57 +01001648 .open = nonseekable_open,
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001649 .unlocked_ioctl = dm_ctl_ioctl,
Milan Broz76c072b2008-02-08 02:09:56 +00001650 .compat_ioctl = dm_compat_ctl_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001652 .llseek = noop_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653};
1654
1655static struct miscdevice _dm_misc = {
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001656 .minor = MAPPER_CTRL_MINOR,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 .name = DM_NAME,
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001658 .nodename = DM_DIR "/" DM_CONTROL_NODE,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659 .fops = &_ctl_fops
1660};
1661
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001662MODULE_ALIAS_MISCDEV(MAPPER_CTRL_MINOR);
1663MODULE_ALIAS("devname:" DM_DIR "/" DM_CONTROL_NODE);
1664
Linus Torvalds1da177e2005-04-16 15:20:36 -07001665/*
1666 * Create misc character device and link to DM_DIR/control.
1667 */
1668int __init dm_interface_init(void)
1669{
1670 int r;
1671
1672 r = dm_hash_init();
1673 if (r)
1674 return r;
1675
1676 r = misc_register(&_dm_misc);
1677 if (r) {
1678 DMERR("misc_register failed for control device");
1679 dm_hash_exit();
1680 return r;
1681 }
1682
1683 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
1684 DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
1685 DM_DRIVER_EMAIL);
1686 return 0;
1687}
1688
1689void dm_interface_exit(void)
1690{
1691 if (misc_deregister(&_dm_misc) < 0)
1692 DMERR("misc_deregister failed for control device");
1693
1694 dm_hash_exit();
1695}
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001696
1697/**
1698 * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
1699 * @md: Pointer to mapped_device
1700 * @name: Buffer (size DM_NAME_LEN) for name
1701 * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
1702 */
1703int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
1704{
1705 int r = 0;
1706 struct hash_cell *hc;
1707
1708 if (!md)
1709 return -ENXIO;
1710
Mikulas Patocka60769052009-12-10 23:51:52 +00001711 mutex_lock(&dm_hash_cells_mutex);
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001712 hc = dm_get_mdptr(md);
1713 if (!hc || hc->md != md) {
1714 r = -ENXIO;
1715 goto out;
1716 }
1717
Milan Broz23d39f62009-01-06 03:05:04 +00001718 if (name)
1719 strcpy(name, hc->name);
1720 if (uuid)
1721 strcpy(uuid, hc->uuid ? : "");
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001722
1723out:
Mikulas Patocka60769052009-12-10 23:51:52 +00001724 mutex_unlock(&dm_hash_cells_mutex);
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001725
1726 return r;
1727}