blob: 51521429fb59d01ea65e8d1243a1151272f9beca [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
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +010039/*
40 * A dummy definition to make RCU happy.
41 * struct dm_table should never be dereferenced in this file.
42 */
43struct dm_table {
44 int undefined__;
45};
46
Linus Torvalds1da177e2005-04-16 15:20:36 -070047struct vers_iter {
48 size_t param_size;
49 struct dm_target_versions *vers, *old_vers;
50 char *end;
51 uint32_t flags;
52};
53
54
55#define NUM_BUCKETS 64
56#define MASK_BUCKETS (NUM_BUCKETS - 1)
57static struct list_head _name_buckets[NUM_BUCKETS];
58static struct list_head _uuid_buckets[NUM_BUCKETS];
59
Mikulas Patocka2c140a22013-11-01 18:27:41 -040060static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred);
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
62/*
63 * Guards access to both hash tables.
64 */
65static DECLARE_RWSEM(_hash_lock);
66
Mikulas Patocka60769052009-12-10 23:51:52 +000067/*
68 * Protects use of mdptr to obtain hash cell name and uuid from mapped device.
69 */
70static DEFINE_MUTEX(dm_hash_cells_mutex);
71
Linus Torvalds1da177e2005-04-16 15:20:36 -070072static void init_buckets(struct list_head *buckets)
73{
74 unsigned int i;
75
76 for (i = 0; i < NUM_BUCKETS; i++)
77 INIT_LIST_HEAD(buckets + i);
78}
79
80static int dm_hash_init(void)
81{
82 init_buckets(_name_buckets);
83 init_buckets(_uuid_buckets);
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 return 0;
85}
86
87static void dm_hash_exit(void)
88{
Mikulas Patocka2c140a22013-11-01 18:27:41 -040089 dm_hash_remove_all(false, false, false);
Linus Torvalds1da177e2005-04-16 15:20:36 -070090}
91
92/*-----------------------------------------------------------------
93 * Hash function:
94 * We're not really concerned with the str hash function being
95 * fast since it's only used by the ioctl interface.
96 *---------------------------------------------------------------*/
97static unsigned int hash_str(const char *str)
98{
99 const unsigned int hash_mult = 2654435387U;
100 unsigned int h = 0;
101
102 while (*str)
103 h = (h + (unsigned int) *str++) * hash_mult;
104
105 return h & MASK_BUCKETS;
106}
107
108/*-----------------------------------------------------------------
109 * Code for looking up a device by name
110 *---------------------------------------------------------------*/
111static struct hash_cell *__get_name_cell(const char *str)
112{
113 struct hash_cell *hc;
114 unsigned int h = hash_str(str);
115
116 list_for_each_entry (hc, _name_buckets + h, name_list)
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700117 if (!strcmp(hc->name, str)) {
118 dm_get(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 return hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700120 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
122 return NULL;
123}
124
125static struct hash_cell *__get_uuid_cell(const char *str)
126{
127 struct hash_cell *hc;
128 unsigned int h = hash_str(str);
129
130 list_for_each_entry (hc, _uuid_buckets + h, uuid_list)
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700131 if (!strcmp(hc->uuid, str)) {
132 dm_get(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 return hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700134 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135
136 return NULL;
137}
138
Mikulas Patockaba2e19b2011-08-02 12:32:06 +0100139static struct hash_cell *__get_dev_cell(uint64_t dev)
140{
141 struct mapped_device *md;
142 struct hash_cell *hc;
143
144 md = dm_get_md(huge_decode_dev(dev));
145 if (!md)
146 return NULL;
147
148 hc = dm_get_mdptr(md);
149 if (!hc) {
150 dm_put(md);
151 return NULL;
152 }
153
154 return hc;
155}
156
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157/*-----------------------------------------------------------------
158 * Inserting, removing and renaming a device.
159 *---------------------------------------------------------------*/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160static struct hash_cell *alloc_cell(const char *name, const char *uuid,
161 struct mapped_device *md)
162{
163 struct hash_cell *hc;
164
165 hc = kmalloc(sizeof(*hc), GFP_KERNEL);
166 if (!hc)
167 return NULL;
168
Paulo Marques543537b2005-06-23 00:09:02 -0700169 hc->name = kstrdup(name, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 if (!hc->name) {
171 kfree(hc);
172 return NULL;
173 }
174
175 if (!uuid)
176 hc->uuid = NULL;
177
178 else {
Paulo Marques543537b2005-06-23 00:09:02 -0700179 hc->uuid = kstrdup(uuid, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 if (!hc->uuid) {
181 kfree(hc->name);
182 kfree(hc);
183 return NULL;
184 }
185 }
186
187 INIT_LIST_HEAD(&hc->name_list);
188 INIT_LIST_HEAD(&hc->uuid_list);
189 hc->md = md;
190 hc->new_map = NULL;
191 return hc;
192}
193
194static void free_cell(struct hash_cell *hc)
195{
196 if (hc) {
197 kfree(hc->name);
198 kfree(hc->uuid);
199 kfree(hc);
200 }
201}
202
203/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 * The kdev_t and uuid of a device can never change once it is
205 * initially inserted.
206 */
207static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
208{
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700209 struct hash_cell *cell, *hc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210
211 /*
212 * Allocate the new cells.
213 */
214 cell = alloc_cell(name, uuid, md);
215 if (!cell)
216 return -ENOMEM;
217
218 /*
219 * Insert the cell into both hash tables.
220 */
221 down_write(&_hash_lock);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700222 hc = __get_name_cell(name);
223 if (hc) {
224 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 goto bad;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700226 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227
228 list_add(&cell->name_list, _name_buckets + hash_str(name));
229
230 if (uuid) {
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700231 hc = __get_uuid_cell(uuid);
232 if (hc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 list_del(&cell->name_list);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700234 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 goto bad;
236 }
237 list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
238 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 dm_get(md);
Mikulas Patocka60769052009-12-10 23:51:52 +0000240 mutex_lock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 dm_set_mdptr(md, cell);
Mikulas Patocka60769052009-12-10 23:51:52 +0000242 mutex_unlock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 up_write(&_hash_lock);
244
245 return 0;
246
247 bad:
248 up_write(&_hash_lock);
249 free_cell(cell);
250 return -EBUSY;
251}
252
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100253static struct dm_table *__hash_remove(struct hash_cell *hc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254{
goggin, edward269fd2a2005-09-27 21:45:44 -0700255 struct dm_table *table;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100256 int srcu_idx;
goggin, edward269fd2a2005-09-27 21:45:44 -0700257
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 /* remove from the dev hash */
259 list_del(&hc->uuid_list);
260 list_del(&hc->name_list);
Mikulas Patocka60769052009-12-10 23:51:52 +0000261 mutex_lock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 dm_set_mdptr(hc->md, NULL);
Mikulas Patocka60769052009-12-10 23:51:52 +0000263 mutex_unlock(&dm_hash_cells_mutex);
goggin, edward269fd2a2005-09-27 21:45:44 -0700264
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100265 table = dm_get_live_table(hc->md, &srcu_idx);
266 if (table)
goggin, edward269fd2a2005-09-27 21:45:44 -0700267 dm_table_event(table);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100268 dm_put_live_table(hc->md, srcu_idx);
goggin, edward269fd2a2005-09-27 21:45:44 -0700269
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100270 table = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 if (hc->new_map)
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100272 table = hc->new_map;
Mike Anderson1134e5a2006-03-27 01:17:54 -0800273 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700274 free_cell(hc);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100275
276 return table;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277}
278
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400279static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280{
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100281 int i, dev_skipped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 struct hash_cell *hc;
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100283 struct mapped_device *md;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100284 struct dm_table *t;
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100285
286retry:
287 dev_skipped = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288
289 down_write(&_hash_lock);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700290
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 for (i = 0; i < NUM_BUCKETS; i++) {
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100292 list_for_each_entry(hc, _name_buckets + i, name_list) {
293 md = hc->md;
294 dm_get(md);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700295
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400296 if (keep_open_devices &&
297 dm_lock_for_deletion(md, mark_deferred, only_deferred)) {
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100298 dm_put(md);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700299 dev_skipped++;
300 continue;
301 }
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100302
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100303 t = __hash_remove(hc);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100304
305 up_write(&_hash_lock);
306
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100307 if (t) {
308 dm_sync_table(md);
309 dm_table_destroy(t);
310 }
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100311 dm_put(md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100312 if (likely(keep_open_devices))
313 dm_destroy(md);
314 else
315 dm_destroy_immediate(md);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100316
317 /*
318 * Some mapped devices may be using other mapped
319 * devices, so repeat until we make no further
320 * progress. If a new mapped device is created
321 * here it will also get removed.
322 */
323 goto retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 }
325 }
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700326
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 up_write(&_hash_lock);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100328
329 if (dev_skipped)
330 DMWARN("remove_all left %d open device(s)", dev_skipped);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331}
332
Peter Jones84c89552011-01-13 19:59:47 +0000333/*
334 * Set the uuid of a hash_cell that isn't already set.
335 */
336static void __set_cell_uuid(struct hash_cell *hc, char *new_uuid)
337{
338 mutex_lock(&dm_hash_cells_mutex);
339 hc->uuid = new_uuid;
340 mutex_unlock(&dm_hash_cells_mutex);
341
342 list_add(&hc->uuid_list, _uuid_buckets + hash_str(new_uuid));
343}
344
345/*
346 * Changes the name of a hash_cell and returns the old name for
347 * the caller to free.
348 */
349static char *__change_cell_name(struct hash_cell *hc, char *new_name)
350{
351 char *old_name;
352
353 /*
354 * Rename and move the name cell.
355 */
356 list_del(&hc->name_list);
357 old_name = hc->name;
358
359 mutex_lock(&dm_hash_cells_mutex);
360 hc->name = new_name;
361 mutex_unlock(&dm_hash_cells_mutex);
362
363 list_add(&hc->name_list, _name_buckets + hash_str(new_name));
364
365 return old_name;
366}
367
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100368static struct mapped_device *dm_hash_rename(struct dm_ioctl *param,
369 const char *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370{
Peter Jones84c89552011-01-13 19:59:47 +0000371 char *new_data, *old_name = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 struct hash_cell *hc;
goggin, edward81f17772006-01-06 00:20:01 -0800373 struct dm_table *table;
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100374 struct mapped_device *md;
Peter Jones84c89552011-01-13 19:59:47 +0000375 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100376 int srcu_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
378 /*
379 * duplicate new.
380 */
Peter Jones84c89552011-01-13 19:59:47 +0000381 new_data = kstrdup(new, GFP_KERNEL);
382 if (!new_data)
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100383 return ERR_PTR(-ENOMEM);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384
385 down_write(&_hash_lock);
386
387 /*
388 * Is new free ?
389 */
Peter Jones84c89552011-01-13 19:59:47 +0000390 if (change_uuid)
391 hc = __get_uuid_cell(new);
392 else
393 hc = __get_name_cell(new);
394
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 if (hc) {
Peter Jones84c89552011-01-13 19:59:47 +0000396 DMWARN("Unable to change %s on mapped device %s to one that "
397 "already exists: %s",
398 change_uuid ? "uuid" : "name",
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100399 param->name, new);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700400 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 up_write(&_hash_lock);
Peter Jones84c89552011-01-13 19:59:47 +0000402 kfree(new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100403 return ERR_PTR(-EBUSY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 }
405
406 /*
407 * Is there such a device as 'old' ?
408 */
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100409 hc = __get_name_cell(param->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 if (!hc) {
Peter Jones84c89552011-01-13 19:59:47 +0000411 DMWARN("Unable to rename non-existent device, %s to %s%s",
412 param->name, change_uuid ? "uuid " : "", new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 up_write(&_hash_lock);
Peter Jones84c89552011-01-13 19:59:47 +0000414 kfree(new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100415 return ERR_PTR(-ENXIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416 }
417
418 /*
Peter Jones84c89552011-01-13 19:59:47 +0000419 * Does this device already have a uuid?
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 */
Peter Jones84c89552011-01-13 19:59:47 +0000421 if (change_uuid && hc->uuid) {
422 DMWARN("Unable to change uuid of mapped device %s to %s "
423 "because uuid is already set to %s",
424 param->name, new, hc->uuid);
425 dm_put(hc->md);
426 up_write(&_hash_lock);
427 kfree(new_data);
428 return ERR_PTR(-EINVAL);
429 }
430
431 if (change_uuid)
432 __set_cell_uuid(hc, new_data);
433 else
434 old_name = __change_cell_name(hc, new_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435
goggin, edward81f17772006-01-06 00:20:01 -0800436 /*
437 * Wake up any dm event waiters.
438 */
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100439 table = dm_get_live_table(hc->md, &srcu_idx);
440 if (table)
goggin, edward81f17772006-01-06 00:20:01 -0800441 dm_table_event(table);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100442 dm_put_live_table(hc->md, srcu_idx);
goggin, edward81f17772006-01-06 00:20:01 -0800443
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100444 if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, param->event_nr))
445 param->flags |= DM_UEVENT_GENERATED_FLAG;
Alasdair G Kergon69267a32007-12-13 14:15:57 +0000446
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100447 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 up_write(&_hash_lock);
449 kfree(old_name);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100450
451 return md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452}
453
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400454void dm_deferred_remove(void)
455{
456 dm_hash_remove_all(true, false, true);
457}
458
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459/*-----------------------------------------------------------------
460 * Implementation of the ioctl commands
461 *---------------------------------------------------------------*/
462/*
463 * All the ioctl commands get dispatched to functions with this
464 * prototype.
465 */
466typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size);
467
468static int remove_all(struct dm_ioctl *param, size_t param_size)
469{
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400470 dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 param->data_size = 0;
472 return 0;
473}
474
475/*
476 * Round up the ptr to an 8-byte boundary.
477 */
478#define ALIGN_MASK 7
479static inline void *align_ptr(void *ptr)
480{
481 return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK);
482}
483
484/*
485 * Retrieves the data payload buffer from an already allocated
486 * struct dm_ioctl.
487 */
488static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
489 size_t *len)
490{
491 param->data_start = align_ptr(param + 1) - (void *) param;
492
493 if (param->data_start < param_size)
494 *len = param_size - param->data_start;
495 else
496 *len = 0;
497
498 return ((void *) param) + param->data_start;
499}
500
501static int list_devices(struct dm_ioctl *param, size_t param_size)
502{
503 unsigned int i;
504 struct hash_cell *hc;
505 size_t len, needed = 0;
506 struct gendisk *disk;
507 struct dm_name_list *nl, *old_nl = NULL;
508
509 down_write(&_hash_lock);
510
511 /*
512 * Loop through all the devices working out how much
513 * space we need.
514 */
515 for (i = 0; i < NUM_BUCKETS; i++) {
516 list_for_each_entry (hc, _name_buckets + i, name_list) {
517 needed += sizeof(struct dm_name_list);
518 needed += strlen(hc->name) + 1;
519 needed += ALIGN_MASK;
520 }
521 }
522
523 /*
524 * Grab our output buffer.
525 */
526 nl = get_result_buffer(param, param_size, &len);
527 if (len < needed) {
528 param->flags |= DM_BUFFER_FULL_FLAG;
529 goto out;
530 }
531 param->data_size = param->data_start + needed;
532
533 nl->dev = 0; /* Flags no data */
534
535 /*
536 * Now loop through filling out the names.
537 */
538 for (i = 0; i < NUM_BUCKETS; i++) {
539 list_for_each_entry (hc, _name_buckets + i, name_list) {
540 if (old_nl)
541 old_nl->next = (uint32_t) ((void *) nl -
542 (void *) old_nl);
543 disk = dm_disk(hc->md);
Tejun Heof331c022008-09-03 09:01:48 +0200544 nl->dev = huge_encode_dev(disk_devt(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 nl->next = 0;
546 strcpy(nl->name, hc->name);
547
548 old_nl = nl;
549 nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1);
550 }
551 }
552
553 out:
554 up_write(&_hash_lock);
555 return 0;
556}
557
558static void list_version_get_needed(struct target_type *tt, void *needed_param)
559{
560 size_t *needed = needed_param;
561
Alasdair G Kergonc4cc6632005-11-21 21:32:33 -0800562 *needed += sizeof(struct dm_target_versions);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563 *needed += strlen(tt->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 *needed += ALIGN_MASK;
565}
566
567static void list_version_get_info(struct target_type *tt, void *param)
568{
569 struct vers_iter *info = param;
570
571 /* Check space - it might have changed since the first iteration */
572 if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 >
573 info->end) {
574
575 info->flags = DM_BUFFER_FULL_FLAG;
576 return;
577 }
578
579 if (info->old_vers)
580 info->old_vers->next = (uint32_t) ((void *)info->vers -
581 (void *)info->old_vers);
582 info->vers->version[0] = tt->version[0];
583 info->vers->version[1] = tt->version[1];
584 info->vers->version[2] = tt->version[2];
585 info->vers->next = 0;
586 strcpy(info->vers->name, tt->name);
587
588 info->old_vers = info->vers;
589 info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
590}
591
592static int list_versions(struct dm_ioctl *param, size_t param_size)
593{
594 size_t len, needed = 0;
595 struct dm_target_versions *vers;
596 struct vers_iter iter_info;
597
598 /*
599 * Loop through all the devices working out how much
600 * space we need.
601 */
602 dm_target_iterate(list_version_get_needed, &needed);
603
604 /*
605 * Grab our output buffer.
606 */
607 vers = get_result_buffer(param, param_size, &len);
608 if (len < needed) {
609 param->flags |= DM_BUFFER_FULL_FLAG;
610 goto out;
611 }
612 param->data_size = param->data_start + needed;
613
614 iter_info.param_size = param_size;
615 iter_info.old_vers = NULL;
616 iter_info.vers = vers;
617 iter_info.flags = 0;
618 iter_info.end = (char *)vers+len;
619
620 /*
621 * Now loop through filling out the names & versions.
622 */
623 dm_target_iterate(list_version_get_info, &iter_info);
624 param->flags |= iter_info.flags;
625
626 out:
627 return 0;
628}
629
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630static int check_name(const char *name)
631{
632 if (strchr(name, '/')) {
633 DMWARN("invalid device name");
634 return -EINVAL;
635 }
636
637 return 0;
638}
639
640/*
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000641 * On successful return, the caller must not attempt to acquire
642 * _hash_lock without first calling dm_table_put, because dm_table_destroy
643 * waits for this dm_table_put and could be called under this lock.
644 */
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100645static struct dm_table *dm_get_inactive_table(struct mapped_device *md, int *srcu_idx)
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000646{
647 struct hash_cell *hc;
648 struct dm_table *table = NULL;
649
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100650 /* increment rcu count, we don't care about the table pointer */
651 dm_get_live_table(md, srcu_idx);
652
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000653 down_read(&_hash_lock);
654 hc = dm_get_mdptr(md);
655 if (!hc || hc->md != md) {
656 DMWARN("device has been removed from the dev hash table.");
657 goto out;
658 }
659
660 table = hc->new_map;
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000661
662out:
663 up_read(&_hash_lock);
664
665 return table;
666}
667
668static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md,
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100669 struct dm_ioctl *param,
670 int *srcu_idx)
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000671{
672 return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ?
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100673 dm_get_inactive_table(md, srcu_idx) : dm_get_live_table(md, srcu_idx);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000674}
675
676/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 * Fills in a dm_ioctl structure, ready for sending back to
678 * userland.
679 */
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100680static void __dev_status(struct mapped_device *md, struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681{
682 struct gendisk *disk = dm_disk(md);
683 struct dm_table *table;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100684 int srcu_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685
686 param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
687 DM_ACTIVE_PRESENT_FLAG);
688
Kiyoshi Ueda4f186f82009-12-10 23:52:26 +0000689 if (dm_suspended_md(md))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 param->flags |= DM_SUSPEND_FLAG;
691
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400692 if (dm_test_deferred_remove_flag(md))
693 param->flags |= DM_DEFERRED_REMOVE;
694
Tejun Heof331c022008-09-03 09:01:48 +0200695 param->dev = huge_encode_dev(disk_devt(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700697 /*
698 * Yes, this will be out of date by the time it gets back
699 * to userland, but it is still very useful for
700 * debugging.
701 */
702 param->open_count = dm_open_count(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704 param->event_nr = dm_get_event_nr(md);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000705 param->target_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100707 table = dm_get_live_table(md, &srcu_idx);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708 if (table) {
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000709 if (!(param->flags & DM_QUERY_INACTIVE_TABLE_FLAG)) {
710 if (get_disk_ro(disk))
711 param->flags |= DM_READONLY_FLAG;
712 param->target_count = dm_table_get_num_targets(table);
713 }
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000714
715 param->flags |= DM_ACTIVE_PRESENT_FLAG;
716 }
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100717 dm_put_live_table(md, srcu_idx);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000718
719 if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) {
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100720 int srcu_idx;
721 table = dm_get_inactive_table(md, &srcu_idx);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000722 if (table) {
723 if (!(dm_table_get_mode(table) & FMODE_WRITE))
724 param->flags |= DM_READONLY_FLAG;
725 param->target_count = dm_table_get_num_targets(table);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000726 }
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100727 dm_put_live_table(md, srcu_idx);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000728 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729}
730
731static int dev_create(struct dm_ioctl *param, size_t param_size)
732{
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700733 int r, m = DM_ANY_MINOR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 struct mapped_device *md;
735
736 r = check_name(param->name);
737 if (r)
738 return r;
739
740 if (param->flags & DM_PERSISTENT_DEV_FLAG)
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700741 m = MINOR(huge_decode_dev(param->dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700743 r = dm_create(m, &md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 if (r)
745 return r;
746
747 r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100748 if (r) {
749 dm_put(md);
750 dm_destroy(md);
751 return r;
752 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753
754 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
755
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100756 __dev_status(md, param);
757
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 dm_put(md);
759
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100760 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761}
762
763/*
764 * Always use UUID for lookups if it's present, otherwise use name or dev.
765 */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800766static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767{
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100768 struct hash_cell *hc = NULL;
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800769
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100770 if (*param->uuid) {
Mikulas Patocka759dea22011-08-02 12:32:06 +0100771 if (*param->name || param->dev)
772 return NULL;
773
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100774 hc = __get_uuid_cell(param->uuid);
775 if (!hc)
776 return NULL;
Mikulas Patockaba2e19b2011-08-02 12:32:06 +0100777 } else if (*param->name) {
Mikulas Patocka759dea22011-08-02 12:32:06 +0100778 if (param->dev)
779 return NULL;
780
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100781 hc = __get_name_cell(param->name);
782 if (!hc)
783 return NULL;
Mikulas Patockaba2e19b2011-08-02 12:32:06 +0100784 } else if (param->dev) {
785 hc = __get_dev_cell(param->dev);
786 if (!hc)
787 return NULL;
788 } else
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100789 return NULL;
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800790
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100791 /*
792 * Sneakily write in both the name and the uuid
793 * while we have the cell.
794 */
795 strlcpy(param->name, hc->name, sizeof(param->name));
796 if (hc->uuid)
797 strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
798 else
799 param->uuid[0] = '\0';
800
801 if (hc->new_map)
802 param->flags |= DM_INACTIVE_PRESENT_FLAG;
803 else
804 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
805
806 return hc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807}
808
Arjan van de Ven858119e2006-01-14 13:20:43 -0800809static struct mapped_device *find_device(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810{
811 struct hash_cell *hc;
812 struct mapped_device *md = NULL;
813
814 down_read(&_hash_lock);
815 hc = __find_device_hash_cell(param);
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100816 if (hc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 up_read(&_hash_lock);
819
820 return md;
821}
822
823static int dev_remove(struct dm_ioctl *param, size_t param_size)
824{
825 struct hash_cell *hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700826 struct mapped_device *md;
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700827 int r;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100828 struct dm_table *t;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829
830 down_write(&_hash_lock);
831 hc = __find_device_hash_cell(param);
832
833 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +0000834 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 up_write(&_hash_lock);
836 return -ENXIO;
837 }
838
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700839 md = hc->md;
840
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700841 /*
842 * Ensure the device is not open and nothing further can open it.
843 */
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400844 r = dm_lock_for_deletion(md, !!(param->flags & DM_DEFERRED_REMOVE), false);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700845 if (r) {
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400846 if (r == -EBUSY && param->flags & DM_DEFERRED_REMOVE) {
847 up_write(&_hash_lock);
848 dm_put(md);
849 return 0;
850 }
Milan Broz810b4922011-01-13 19:59:55 +0000851 DMDEBUG_LIMIT("unable to remove open device %s", hc->name);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700852 up_write(&_hash_lock);
853 dm_put(md);
854 return r;
855 }
856
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100857 t = __hash_remove(hc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858 up_write(&_hash_lock);
Milan Broz60935eb2009-06-22 10:12:30 +0100859
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +0100860 if (t) {
861 dm_sync_table(md);
862 dm_table_destroy(t);
863 }
864
Mikulas Patocka2c140a22013-11-01 18:27:41 -0400865 param->flags &= ~DM_DEFERRED_REMOVE;
866
Peter Rajnoha3abf85b2010-03-06 02:32:31 +0000867 if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr))
868 param->flags |= DM_UEVENT_GENERATED_FLAG;
Milan Broz60935eb2009-06-22 10:12:30 +0100869
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700870 dm_put(md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100871 dm_destroy(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872 return 0;
873}
874
875/*
876 * Check a string doesn't overrun the chunk of
877 * memory we copied from userland.
878 */
879static int invalid_str(char *str, void *end)
880{
881 while ((void *) str < end)
882 if (!*str++)
883 return 0;
884
885 return -EINVAL;
886}
887
888static int dev_rename(struct dm_ioctl *param, size_t param_size)
889{
890 int r;
Peter Jones84c89552011-01-13 19:59:47 +0000891 char *new_data = (char *) param + param->data_start;
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100892 struct mapped_device *md;
Peter Jones84c89552011-01-13 19:59:47 +0000893 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894
Peter Jones84c89552011-01-13 19:59:47 +0000895 if (new_data < param->data ||
Alasdair Kergonc2b04822013-08-29 16:37:45 +0100896 invalid_str(new_data, (void *) param + param_size) || !*new_data ||
Peter Jones84c89552011-01-13 19:59:47 +0000897 strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) {
898 DMWARN("Invalid new mapped device name or uuid string supplied.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700899 return -EINVAL;
900 }
901
Peter Jones84c89552011-01-13 19:59:47 +0000902 if (!change_uuid) {
903 r = check_name(new_data);
904 if (r)
905 return r;
906 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700907
Peter Jones84c89552011-01-13 19:59:47 +0000908 md = dm_hash_rename(param, new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100909 if (IS_ERR(md))
910 return PTR_ERR(md);
Peter Rajnoha3abf85b2010-03-06 02:32:31 +0000911
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100912 __dev_status(md, param);
913 dm_put(md);
914
915 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916}
917
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800918static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
919{
920 int r = -EINVAL, x;
921 struct mapped_device *md;
922 struct hd_geometry geometry;
923 unsigned long indata[4];
924 char *geostr = (char *) param + param->data_start;
Mikulas Patocka31998ef2012-03-28 18:41:26 +0100925 char dummy;
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800926
927 md = find_device(param);
928 if (!md)
929 return -ENXIO;
930
Alasdair G Kergon27238b22008-02-08 02:09:53 +0000931 if (geostr < param->data ||
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800932 invalid_str(geostr, (void *) param + param_size)) {
933 DMWARN("Invalid geometry supplied.");
934 goto out;
935 }
936
Mikulas Patocka31998ef2012-03-28 18:41:26 +0100937 x = sscanf(geostr, "%lu %lu %lu %lu%c", indata,
938 indata + 1, indata + 2, indata + 3, &dummy);
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800939
940 if (x != 4) {
941 DMWARN("Unable to interpret geometry settings.");
942 goto out;
943 }
944
945 if (indata[0] > 65535 || indata[1] > 255 ||
946 indata[2] > 255 || indata[3] > ULONG_MAX) {
947 DMWARN("Geometry exceeds range limits.");
948 goto out;
949 }
950
951 geometry.cylinders = indata[0];
952 geometry.heads = indata[1];
953 geometry.sectors = indata[2];
954 geometry.start = indata[3];
955
956 r = dm_set_geometry(md, &geometry);
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800957
958 param->data_size = 0;
959
960out:
961 dm_put(md);
962 return r;
963}
964
Linus Torvalds1da177e2005-04-16 15:20:36 -0700965static int do_suspend(struct dm_ioctl *param)
966{
967 int r = 0;
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800968 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969 struct mapped_device *md;
970
971 md = find_device(param);
972 if (!md)
973 return -ENXIO;
974
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800975 if (param->flags & DM_SKIP_LOCKFS_FLAG)
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800976 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
Kiyoshi Ueda81fdb092006-12-08 02:41:07 -0800977 if (param->flags & DM_NOFLUSH_FLAG)
978 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800979
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100980 if (!dm_suspended_md(md)) {
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800981 r = dm_suspend(md, suspend_flags);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100982 if (r)
983 goto out;
984 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100986 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100988out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100990
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 return r;
992}
993
994static int do_resume(struct dm_ioctl *param)
995{
996 int r = 0;
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800997 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998 struct hash_cell *hc;
999 struct mapped_device *md;
Alasdair G Kergon042d2a92009-12-10 23:52:24 +00001000 struct dm_table *new_map, *old_map = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001
1002 down_write(&_hash_lock);
1003
1004 hc = __find_device_hash_cell(param);
1005 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +00001006 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001007 up_write(&_hash_lock);
1008 return -ENXIO;
1009 }
1010
1011 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012
1013 new_map = hc->new_map;
1014 hc->new_map = NULL;
1015 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1016
1017 up_write(&_hash_lock);
1018
1019 /* Do we need to load a new map ? */
1020 if (new_map) {
1021 /* Suspend if it isn't already suspended */
Alasdair G Kergon6da487d2006-01-06 00:20:07 -08001022 if (param->flags & DM_SKIP_LOCKFS_FLAG)
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -08001023 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
Kiyoshi Ueda81fdb092006-12-08 02:41:07 -08001024 if (param->flags & DM_NOFLUSH_FLAG)
1025 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
Kiyoshi Ueda4f186f82009-12-10 23:52:26 +00001026 if (!dm_suspended_md(md))
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -08001027 dm_suspend(md, suspend_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028
Alasdair G Kergon042d2a92009-12-10 23:52:24 +00001029 old_map = dm_swap_table(md, new_map);
1030 if (IS_ERR(old_map)) {
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001031 dm_sync_table(md);
Mikulas Patockad5816872009-01-06 03:05:10 +00001032 dm_table_destroy(new_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033 dm_put(md);
Alasdair G Kergon042d2a92009-12-10 23:52:24 +00001034 return PTR_ERR(old_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035 }
1036
1037 if (dm_table_get_mode(new_map) & FMODE_WRITE)
1038 set_disk_ro(dm_disk(md), 0);
1039 else
1040 set_disk_ro(dm_disk(md), 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041 }
1042
Mike Snitzer0f3649a2010-03-06 02:32:24 +00001043 if (dm_suspended_md(md)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044 r = dm_resume(md);
Peter Rajnoha3abf85b2010-03-06 02:32:31 +00001045 if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
1046 param->flags |= DM_UEVENT_GENERATED_FLAG;
Mike Snitzer0f3649a2010-03-06 02:32:24 +00001047 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001048
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001049 /*
1050 * Since dm_swap_table synchronizes RCU, nobody should be in
1051 * read-side critical section already.
1052 */
Alasdair G Kergon042d2a92009-12-10 23:52:24 +00001053 if (old_map)
1054 dm_table_destroy(old_map);
Milan Broz60935eb2009-06-22 10:12:30 +01001055
Mike Snitzer0f3649a2010-03-06 02:32:24 +00001056 if (!r)
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001057 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058
1059 dm_put(md);
1060 return r;
1061}
1062
1063/*
1064 * Set or unset the suspension state of a device.
1065 * If the device already is in the requested state we just return its status.
1066 */
1067static int dev_suspend(struct dm_ioctl *param, size_t param_size)
1068{
1069 if (param->flags & DM_SUSPEND_FLAG)
1070 return do_suspend(param);
1071
1072 return do_resume(param);
1073}
1074
1075/*
1076 * Copies device info back to user space, used by
1077 * the create and info ioctls.
1078 */
1079static int dev_status(struct dm_ioctl *param, size_t param_size)
1080{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 struct mapped_device *md;
1082
1083 md = find_device(param);
1084 if (!md)
1085 return -ENXIO;
1086
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001087 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001088 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001089
1090 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091}
1092
1093/*
1094 * Build up the status struct for each target
1095 */
1096static void retrieve_status(struct dm_table *table,
1097 struct dm_ioctl *param, size_t param_size)
1098{
1099 unsigned int i, num_targets;
1100 struct dm_target_spec *spec;
1101 char *outbuf, *outptr;
1102 status_type_t type;
1103 size_t remaining, len, used = 0;
Alasdair G Kergon1f4e0ff2012-07-27 15:08:16 +01001104 unsigned status_flags = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105
1106 outptr = outbuf = get_result_buffer(param, param_size, &len);
1107
1108 if (param->flags & DM_STATUS_TABLE_FLAG)
1109 type = STATUSTYPE_TABLE;
1110 else
1111 type = STATUSTYPE_INFO;
1112
1113 /* Get all the target info */
1114 num_targets = dm_table_get_num_targets(table);
1115 for (i = 0; i < num_targets; i++) {
1116 struct dm_target *ti = dm_table_get_target(table, i);
Mikulas Patockafd7c0922013-03-01 22:45:44 +00001117 size_t l;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118
1119 remaining = len - (outptr - outbuf);
1120 if (remaining <= sizeof(struct dm_target_spec)) {
1121 param->flags |= DM_BUFFER_FULL_FLAG;
1122 break;
1123 }
1124
1125 spec = (struct dm_target_spec *) outptr;
1126
1127 spec->status = 0;
1128 spec->sector_start = ti->begin;
1129 spec->length = ti->len;
1130 strncpy(spec->target_type, ti->type->name,
1131 sizeof(spec->target_type));
1132
1133 outptr += sizeof(struct dm_target_spec);
1134 remaining = len - (outptr - outbuf);
1135 if (remaining <= 0) {
1136 param->flags |= DM_BUFFER_FULL_FLAG;
1137 break;
1138 }
1139
1140 /* Get the status/table string from the target driver */
1141 if (ti->type->status) {
Alasdair G Kergon1f4e0ff2012-07-27 15:08:16 +01001142 if (param->flags & DM_NOFLUSH_FLAG)
1143 status_flags |= DM_STATUS_NOFLUSH_FLAG;
Mikulas Patockafd7c0922013-03-01 22:45:44 +00001144 ti->type->status(ti, type, status_flags, outptr, remaining);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145 } else
1146 outptr[0] = '\0';
1147
Mikulas Patockafd7c0922013-03-01 22:45:44 +00001148 l = strlen(outptr) + 1;
1149 if (l == remaining) {
1150 param->flags |= DM_BUFFER_FULL_FLAG;
1151 break;
1152 }
1153
1154 outptr += l;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155 used = param->data_start + (outptr - outbuf);
1156
1157 outptr = align_ptr(outptr);
1158 spec->next = outptr - outbuf;
1159 }
1160
1161 if (used)
1162 param->data_size = used;
1163
1164 param->target_count = num_targets;
1165}
1166
1167/*
1168 * Wait for a device to report an event
1169 */
1170static int dev_wait(struct dm_ioctl *param, size_t param_size)
1171{
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001172 int r = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173 struct mapped_device *md;
1174 struct dm_table *table;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001175 int srcu_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176
1177 md = find_device(param);
1178 if (!md)
1179 return -ENXIO;
1180
1181 /*
1182 * Wait for a notification event
1183 */
1184 if (dm_wait_event(md, param->event_nr)) {
1185 r = -ERESTARTSYS;
1186 goto out;
1187 }
1188
1189 /*
1190 * The userland program is going to want to know what
1191 * changed to trigger the event, so we may as well tell
1192 * him and save an ioctl.
1193 */
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001194 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001195
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001196 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1197 if (table)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001198 retrieve_status(table, param, param_size);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001199 dm_put_live_table(md, srcu_idx);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001200
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001201out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001202 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001203
Linus Torvalds1da177e2005-04-16 15:20:36 -07001204 return r;
1205}
1206
Al Viroaeb5d722008-09-02 15:28:45 -04001207static inline fmode_t get_mode(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001208{
Al Viroaeb5d722008-09-02 15:28:45 -04001209 fmode_t mode = FMODE_READ | FMODE_WRITE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001210
1211 if (param->flags & DM_READONLY_FLAG)
1212 mode = FMODE_READ;
1213
1214 return mode;
1215}
1216
1217static int next_target(struct dm_target_spec *last, uint32_t next, void *end,
1218 struct dm_target_spec **spec, char **target_params)
1219{
1220 *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
1221 *target_params = (char *) (*spec + 1);
1222
1223 if (*spec < (last + 1))
1224 return -EINVAL;
1225
1226 return invalid_str(*target_params, end);
1227}
1228
1229static int populate_table(struct dm_table *table,
1230 struct dm_ioctl *param, size_t param_size)
1231{
1232 int r;
1233 unsigned int i = 0;
1234 struct dm_target_spec *spec = (struct dm_target_spec *) param;
1235 uint32_t next = param->data_start;
1236 void *end = (void *) param + param_size;
1237 char *target_params;
1238
1239 if (!param->target_count) {
1240 DMWARN("populate_table: no targets specified");
1241 return -EINVAL;
1242 }
1243
1244 for (i = 0; i < param->target_count; i++) {
1245
1246 r = next_target(spec, next, end, &spec, &target_params);
1247 if (r) {
1248 DMWARN("unable to find target");
1249 return r;
1250 }
1251
1252 r = dm_table_add_target(table, spec->target_type,
1253 (sector_t) spec->sector_start,
1254 (sector_t) spec->length,
1255 target_params);
1256 if (r) {
1257 DMWARN("error adding target to table");
1258 return r;
1259 }
1260
1261 next = spec->next;
1262 }
1263
1264 return dm_table_complete(table);
1265}
1266
1267static int table_load(struct dm_ioctl *param, size_t param_size)
1268{
1269 int r;
1270 struct hash_cell *hc;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001271 struct dm_table *t, *old_map = NULL;
Mike Anderson1134e5a2006-03-27 01:17:54 -08001272 struct mapped_device *md;
Alasdair G Kergon36a04562011-10-31 20:19:04 +00001273 struct target_type *immutable_target_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001274
Mike Anderson1134e5a2006-03-27 01:17:54 -08001275 md = find_device(param);
1276 if (!md)
1277 return -ENXIO;
1278
1279 r = dm_table_create(&t, get_mode(param), param->target_count, md);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280 if (r)
Mike Snitzerf11c1c52013-08-27 20:03:00 -04001281 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001282
Mike Snitzer00c4fc32013-08-27 18:57:03 -04001283 /* Protect md->type and md->queue against concurrent table loads. */
1284 dm_lock_md_type(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285 r = populate_table(t, param, param_size);
Mike Snitzerf11c1c52013-08-27 20:03:00 -04001286 if (r)
1287 goto err_unlock_md_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001288
Alasdair G Kergon36a04562011-10-31 20:19:04 +00001289 immutable_target_type = dm_get_immutable_target_type(md);
1290 if (immutable_target_type &&
1291 (immutable_target_type != dm_table_get_immutable_target_type(t))) {
1292 DMWARN("can't replace immutable target type %s",
1293 immutable_target_type->name);
Alasdair G Kergon36a04562011-10-31 20:19:04 +00001294 r = -EINVAL;
Mike Snitzerf11c1c52013-08-27 20:03:00 -04001295 goto err_unlock_md_type;
Alasdair G Kergon36a04562011-10-31 20:19:04 +00001296 }
1297
Mike Snitzera5664da2010-08-12 04:14:01 +01001298 if (dm_get_md_type(md) == DM_TYPE_NONE)
1299 /* Initial table load: acquire type of table. */
1300 dm_set_md_type(md, dm_table_get_type(t));
1301 else if (dm_get_md_type(md) != dm_table_get_type(t)) {
1302 DMWARN("can't change device type after initial table load.");
Mike Snitzera5664da2010-08-12 04:14:01 +01001303 r = -EINVAL;
Mike Snitzerf11c1c52013-08-27 20:03:00 -04001304 goto err_unlock_md_type;
Mike Snitzera5664da2010-08-12 04:14:01 +01001305 }
Mike Snitzer4a0b4dd2010-08-12 04:14:02 +01001306
1307 /* setup md->queue to reflect md's type (may block) */
1308 r = dm_setup_md_queue(md);
1309 if (r) {
1310 DMWARN("unable to set up device queue for new table.");
Mike Snitzerf11c1c52013-08-27 20:03:00 -04001311 goto err_unlock_md_type;
Mike Snitzer4a0b4dd2010-08-12 04:14:02 +01001312 }
Mike Snitzera5664da2010-08-12 04:14:01 +01001313 dm_unlock_md_type(md);
1314
1315 /* stage inactive table */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001316 down_write(&_hash_lock);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001317 hc = dm_get_mdptr(md);
1318 if (!hc || hc->md != md) {
1319 DMWARN("device has been removed from the dev hash table.");
Mike Anderson1134e5a2006-03-27 01:17:54 -08001320 up_write(&_hash_lock);
1321 r = -ENXIO;
Mike Snitzerf11c1c52013-08-27 20:03:00 -04001322 goto err_destroy_table;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 }
1324
1325 if (hc->new_map)
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001326 old_map = hc->new_map;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327 hc->new_map = t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001328 up_write(&_hash_lock);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001329
1330 param->flags |= DM_INACTIVE_PRESENT_FLAG;
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001331 __dev_status(md, param);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001332
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001333 if (old_map) {
1334 dm_sync_table(md);
1335 dm_table_destroy(old_map);
1336 }
1337
Mike Anderson1134e5a2006-03-27 01:17:54 -08001338 dm_put(md);
1339
Mike Snitzerf11c1c52013-08-27 20:03:00 -04001340 return 0;
1341
1342err_unlock_md_type:
1343 dm_unlock_md_type(md);
1344err_destroy_table:
1345 dm_table_destroy(t);
1346err:
1347 dm_put(md);
1348
Linus Torvalds1da177e2005-04-16 15:20:36 -07001349 return r;
1350}
1351
1352static int table_clear(struct dm_ioctl *param, size_t param_size)
1353{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354 struct hash_cell *hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001355 struct mapped_device *md;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001356 struct dm_table *old_map = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001357
1358 down_write(&_hash_lock);
1359
1360 hc = __find_device_hash_cell(param);
1361 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +00001362 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 up_write(&_hash_lock);
1364 return -ENXIO;
1365 }
1366
1367 if (hc->new_map) {
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001368 old_map = hc->new_map;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369 hc->new_map = NULL;
1370 }
1371
1372 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1373
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001374 __dev_status(hc->md, param);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001375 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001376 up_write(&_hash_lock);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001377 if (old_map) {
1378 dm_sync_table(md);
1379 dm_table_destroy(old_map);
1380 }
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001381 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001382
1383 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001384}
1385
1386/*
1387 * Retrieves a list of devices used by a particular dm device.
1388 */
1389static void retrieve_deps(struct dm_table *table,
1390 struct dm_ioctl *param, size_t param_size)
1391{
1392 unsigned int count = 0;
1393 struct list_head *tmp;
1394 size_t len, needed;
Mikulas Patocka82b15192008-10-10 13:37:09 +01001395 struct dm_dev_internal *dd;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001396 struct dm_target_deps *deps;
1397
1398 deps = get_result_buffer(param, param_size, &len);
1399
1400 /*
1401 * Count the devices.
1402 */
1403 list_for_each (tmp, dm_table_get_devices(table))
1404 count++;
1405
1406 /*
1407 * Check we have enough space.
1408 */
1409 needed = sizeof(*deps) + (sizeof(*deps->dev) * count);
1410 if (len < needed) {
1411 param->flags |= DM_BUFFER_FULL_FLAG;
1412 return;
1413 }
1414
1415 /*
1416 * Fill in the devices.
1417 */
1418 deps->count = count;
1419 count = 0;
1420 list_for_each_entry (dd, dm_table_get_devices(table), list)
Mikulas Patocka82b15192008-10-10 13:37:09 +01001421 deps->dev[count++] = huge_encode_dev(dd->dm_dev.bdev->bd_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001422
1423 param->data_size = param->data_start + needed;
1424}
1425
1426static int table_deps(struct dm_ioctl *param, size_t param_size)
1427{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001428 struct mapped_device *md;
1429 struct dm_table *table;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001430 int srcu_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001431
1432 md = find_device(param);
1433 if (!md)
1434 return -ENXIO;
1435
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001436 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001437
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001438 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1439 if (table)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001440 retrieve_deps(table, param, param_size);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001441 dm_put_live_table(md, srcu_idx);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001442
Linus Torvalds1da177e2005-04-16 15:20:36 -07001443 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001444
1445 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446}
1447
1448/*
1449 * Return the status of a device as a text string for each
1450 * target.
1451 */
1452static int table_status(struct dm_ioctl *param, size_t param_size)
1453{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 struct mapped_device *md;
1455 struct dm_table *table;
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001456 int srcu_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457
1458 md = find_device(param);
1459 if (!md)
1460 return -ENXIO;
1461
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001462 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001463
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001464 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1465 if (table)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466 retrieve_status(table, param, param_size);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001467 dm_put_live_table(md, srcu_idx);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468
Linus Torvalds1da177e2005-04-16 15:20:36 -07001469 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001470
1471 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001472}
1473
Mikulas Patockaa2606242013-03-01 22:45:49 +00001474/*
Mikulas Patockafd2ed4d2013-08-16 10:54:23 -04001475 * Process device-mapper dependent messages. Messages prefixed with '@'
1476 * are processed by the DM core. All others are delivered to the target.
Mikulas Patockaa2606242013-03-01 22:45:49 +00001477 * Returns a number <= 1 if message was processed by device mapper.
1478 * Returns 2 if message should be delivered to the target.
1479 */
1480static int message_for_md(struct mapped_device *md, unsigned argc, char **argv,
1481 char *result, unsigned maxlen)
1482{
Mikulas Patockafd2ed4d2013-08-16 10:54:23 -04001483 int r;
1484
1485 if (**argv != '@')
1486 return 2; /* no '@' prefix, deliver to target */
1487
Mikulas Patocka2c140a22013-11-01 18:27:41 -04001488 if (!strcasecmp(argv[0], "@cancel_deferred_remove")) {
1489 if (argc != 1) {
1490 DMERR("Invalid arguments for @cancel_deferred_remove");
1491 return -EINVAL;
1492 }
1493 return dm_cancel_deferred_remove(md);
1494 }
1495
Mikulas Patockafd2ed4d2013-08-16 10:54:23 -04001496 r = dm_stats_message(md, argc, argv, result, maxlen);
1497 if (r < 2)
1498 return r;
1499
1500 DMERR("Unsupported message sent to DM core: %s", argv[0]);
1501 return -EINVAL;
Mikulas Patockaa2606242013-03-01 22:45:49 +00001502}
1503
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504/*
1505 * Pass a message to the target that's at the supplied device offset.
1506 */
1507static int target_message(struct dm_ioctl *param, size_t param_size)
1508{
1509 int r, argc;
1510 char **argv;
1511 struct mapped_device *md;
1512 struct dm_table *table;
1513 struct dm_target *ti;
1514 struct dm_target_msg *tmsg = (void *) param + param->data_start;
Mikulas Patockaa2606242013-03-01 22:45:49 +00001515 size_t maxlen;
1516 char *result = get_result_buffer(param, param_size, &maxlen);
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001517 int srcu_idx;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518
1519 md = find_device(param);
1520 if (!md)
1521 return -ENXIO;
1522
Milan Broz027d50f2007-10-19 22:38:36 +01001523 if (tmsg < (struct dm_target_msg *) param->data ||
Linus Torvalds1da177e2005-04-16 15:20:36 -07001524 invalid_str(tmsg->message, (void *) param + param_size)) {
1525 DMWARN("Invalid target message parameters.");
1526 r = -EINVAL;
1527 goto out;
1528 }
1529
1530 r = dm_split_args(&argc, &argv, tmsg->message);
1531 if (r) {
1532 DMWARN("Failed to split target message parameters");
1533 goto out;
1534 }
1535
Alasdair G Kergon2ca4c922011-08-02 12:32:03 +01001536 if (!argc) {
1537 DMWARN("Empty message received.");
Jesper Juhl902c6a92012-03-07 19:09:34 +00001538 goto out_argv;
Alasdair G Kergon2ca4c922011-08-02 12:32:03 +01001539 }
1540
Mikulas Patockaa2606242013-03-01 22:45:49 +00001541 r = message_for_md(md, argc, argv, result, maxlen);
1542 if (r <= 1)
1543 goto out_argv;
1544
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001545 table = dm_get_live_table(md, &srcu_idx);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546 if (!table)
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001547 goto out_table;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001548
Mike Andersonc50abeb2009-12-10 23:52:20 +00001549 if (dm_deleting_md(md)) {
1550 r = -ENXIO;
1551 goto out_table;
1552 }
1553
Jun'ichi Nomura512875b2007-12-13 14:15:25 +00001554 ti = dm_table_find_target(table, tmsg->sector);
1555 if (!dm_target_is_valid(ti)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001556 DMWARN("Target message sector outside device.");
1557 r = -EINVAL;
Jun'ichi Nomura512875b2007-12-13 14:15:25 +00001558 } else if (ti->type->message)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001559 r = ti->type->message(ti, argc, argv);
1560 else {
1561 DMWARN("Target type does not support messages");
1562 r = -EINVAL;
1563 }
1564
Mike Andersonc50abeb2009-12-10 23:52:20 +00001565 out_table:
Mikulas Patocka83d5e5b2013-07-10 23:41:18 +01001566 dm_put_live_table(md, srcu_idx);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001567 out_argv:
1568 kfree(argv);
1569 out:
Mikulas Patockaa2606242013-03-01 22:45:49 +00001570 if (r >= 0)
1571 __dev_status(md, param);
1572
1573 if (r == 1) {
1574 param->flags |= DM_DATA_OUT_FLAG;
Mikulas Patockafd2ed4d2013-08-16 10:54:23 -04001575 if (dm_message_test_buffer_overflow(result, maxlen))
Mikulas Patockaa2606242013-03-01 22:45:49 +00001576 param->flags |= DM_BUFFER_FULL_FLAG;
1577 else
1578 param->data_size = param->data_start + strlen(result) + 1;
1579 r = 0;
1580 }
1581
Linus Torvalds1da177e2005-04-16 15:20:36 -07001582 dm_put(md);
1583 return r;
1584}
1585
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001586/*
1587 * The ioctl parameter block consists of two parts, a dm_ioctl struct
1588 * followed by a data buffer. This flag is set if the second part,
1589 * which has a variable size, is not used by the function processing
1590 * the ioctl.
1591 */
1592#define IOCTL_FLAGS_NO_PARAMS 1
1593
Linus Torvalds1da177e2005-04-16 15:20:36 -07001594/*-----------------------------------------------------------------
1595 * Implementation of open/close/ioctl on the special char
1596 * device.
1597 *---------------------------------------------------------------*/
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001598static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599{
1600 static struct {
1601 int cmd;
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001602 int flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001603 ioctl_fn fn;
1604 } _ioctls[] = {
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001605 {DM_VERSION_CMD, 0, NULL}, /* version is dealt with elsewhere */
1606 {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS, remove_all},
1607 {DM_LIST_DEVICES_CMD, 0, list_devices},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001609 {DM_DEV_CREATE_CMD, IOCTL_FLAGS_NO_PARAMS, dev_create},
1610 {DM_DEV_REMOVE_CMD, IOCTL_FLAGS_NO_PARAMS, dev_remove},
1611 {DM_DEV_RENAME_CMD, 0, dev_rename},
1612 {DM_DEV_SUSPEND_CMD, IOCTL_FLAGS_NO_PARAMS, dev_suspend},
1613 {DM_DEV_STATUS_CMD, IOCTL_FLAGS_NO_PARAMS, dev_status},
1614 {DM_DEV_WAIT_CMD, 0, dev_wait},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001615
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001616 {DM_TABLE_LOAD_CMD, 0, table_load},
1617 {DM_TABLE_CLEAR_CMD, IOCTL_FLAGS_NO_PARAMS, table_clear},
1618 {DM_TABLE_DEPS_CMD, 0, table_deps},
1619 {DM_TABLE_STATUS_CMD, 0, table_status},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001620
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001621 {DM_LIST_VERSIONS_CMD, 0, list_versions},
Linus Torvalds1da177e2005-04-16 15:20:36 -07001622
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001623 {DM_TARGET_MSG_CMD, 0, target_message},
1624 {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625 };
1626
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001627 if (unlikely(cmd >= ARRAY_SIZE(_ioctls)))
1628 return NULL;
1629
1630 *ioctl_flags = _ioctls[cmd].flags;
1631 return _ioctls[cmd].fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001632}
1633
1634/*
1635 * As well as checking the version compatibility this always
1636 * copies the kernel interface version out.
1637 */
1638static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
1639{
1640 uint32_t version[3];
1641 int r = 0;
1642
1643 if (copy_from_user(version, user->version, sizeof(version)))
1644 return -EFAULT;
1645
1646 if ((DM_VERSION_MAJOR != version[0]) ||
1647 (DM_VERSION_MINOR < version[1])) {
1648 DMWARN("ioctl interface mismatch: "
1649 "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1650 DM_VERSION_MAJOR, DM_VERSION_MINOR,
1651 DM_VERSION_PATCHLEVEL,
1652 version[0], version[1], version[2], cmd);
1653 r = -EINVAL;
1654 }
1655
1656 /*
1657 * Fill in the kernel version.
1658 */
1659 version[0] = DM_VERSION_MAJOR;
1660 version[1] = DM_VERSION_MINOR;
1661 version[2] = DM_VERSION_PATCHLEVEL;
1662 if (copy_to_user(user->version, version, sizeof(version)))
1663 return -EFAULT;
1664
1665 return r;
1666}
1667
Mikulas Patocka02cde502013-03-01 22:45:49 +00001668#define DM_PARAMS_KMALLOC 0x0001 /* Params alloced with kmalloc */
1669#define DM_PARAMS_VMALLOC 0x0002 /* Params alloced with vmalloc */
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001670#define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */
1671
1672static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags)
1673{
1674 if (param_flags & DM_WIPE_BUFFER)
1675 memset(param, 0, param_size);
1676
Mikulas Patocka02cde502013-03-01 22:45:49 +00001677 if (param_flags & DM_PARAMS_KMALLOC)
1678 kfree(param);
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001679 if (param_flags & DM_PARAMS_VMALLOC)
1680 vfree(param);
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001681}
1682
Mikulas Patocka02cde502013-03-01 22:45:49 +00001683static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel,
1684 int ioctl_flags,
1685 struct dm_ioctl **param, int *param_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001686{
Mikulas Patocka02cde502013-03-01 22:45:49 +00001687 struct dm_ioctl *dmi;
Milan Brozf8681202011-03-24 13:54:30 +00001688 int secure_data;
Mikulas Patocka02cde502013-03-01 22:45:49 +00001689 const size_t minimum_data_size = sizeof(*param_kernel) - sizeof(param_kernel->data);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690
Mikulas Patocka02cde502013-03-01 22:45:49 +00001691 if (copy_from_user(param_kernel, user, minimum_data_size))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001692 return -EFAULT;
1693
Mikulas Patocka02cde502013-03-01 22:45:49 +00001694 if (param_kernel->data_size < minimum_data_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001695 return -EINVAL;
1696
Mikulas Patocka02cde502013-03-01 22:45:49 +00001697 secure_data = param_kernel->flags & DM_SECURE_DATA_FLAG;
Milan Brozf8681202011-03-24 13:54:30 +00001698
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001699 *param_flags = secure_data ? DM_WIPE_BUFFER : 0;
1700
Mikulas Patocka02cde502013-03-01 22:45:49 +00001701 if (ioctl_flags & IOCTL_FLAGS_NO_PARAMS) {
1702 dmi = param_kernel;
1703 dmi->data_size = minimum_data_size;
1704 goto data_copied;
1705 }
1706
Mikulas Patocka5023e5c2012-12-21 20:23:36 +00001707 /*
1708 * Try to avoid low memory issues when a device is suspended.
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001709 * Use kmalloc() rather than vmalloc() when we can.
Mikulas Patocka5023e5c2012-12-21 20:23:36 +00001710 */
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001711 dmi = NULL;
Mikulas Patocka02cde502013-03-01 22:45:49 +00001712 if (param_kernel->data_size <= KMALLOC_MAX_SIZE) {
1713 dmi = kmalloc(param_kernel->data_size, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
1714 if (dmi)
1715 *param_flags |= DM_PARAMS_KMALLOC;
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001716 }
1717
Milan Brozf8681202011-03-24 13:54:30 +00001718 if (!dmi) {
Mikulas Patocka1c0e8832013-07-10 23:41:15 +01001719 unsigned noio_flag;
1720 noio_flag = memalloc_noio_save();
Mikulas Patocka220cd052013-07-10 23:41:16 +01001721 dmi = __vmalloc(param_kernel->data_size, GFP_NOIO | __GFP_REPEAT | __GFP_HIGH | __GFP_HIGHMEM, PAGE_KERNEL);
Mikulas Patocka1c0e8832013-07-10 23:41:15 +01001722 memalloc_noio_restore(noio_flag);
Mikulas Patocka02cde502013-03-01 22:45:49 +00001723 if (dmi)
1724 *param_flags |= DM_PARAMS_VMALLOC;
1725 }
1726
1727 if (!dmi) {
1728 if (secure_data && clear_user(user, param_kernel->data_size))
Milan Brozf8681202011-03-24 13:54:30 +00001729 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001730 return -ENOMEM;
Milan Brozf8681202011-03-24 13:54:30 +00001731 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001732
Mikulas Patocka02cde502013-03-01 22:45:49 +00001733 if (copy_from_user(dmi, user, param_kernel->data_size))
Milan Broz6bb43b52011-03-24 13:54:28 +00001734 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001735
Mikulas Patocka02cde502013-03-01 22:45:49 +00001736data_copied:
Alasdair G Kergone910d7e2012-12-21 20:23:30 +00001737 /*
1738 * Abort if something changed the ioctl data while it was being copied.
1739 */
Mikulas Patocka02cde502013-03-01 22:45:49 +00001740 if (dmi->data_size != param_kernel->data_size) {
Alasdair G Kergone910d7e2012-12-21 20:23:30 +00001741 DMERR("rejecting ioctl: data size modified while processing parameters");
1742 goto bad;
1743 }
1744
Milan Brozf8681202011-03-24 13:54:30 +00001745 /* Wipe the user buffer so we do not return it to userspace */
Mikulas Patocka02cde502013-03-01 22:45:49 +00001746 if (secure_data && clear_user(user, param_kernel->data_size))
Milan Brozf8681202011-03-24 13:54:30 +00001747 goto bad;
1748
Linus Torvalds1da177e2005-04-16 15:20:36 -07001749 *param = dmi;
1750 return 0;
Milan Broz6bb43b52011-03-24 13:54:28 +00001751
1752bad:
Mikulas Patocka02cde502013-03-01 22:45:49 +00001753 free_params(dmi, param_kernel->data_size, *param_flags);
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001754
Milan Broz6bb43b52011-03-24 13:54:28 +00001755 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001756}
1757
1758static int validate_params(uint cmd, struct dm_ioctl *param)
1759{
1760 /* Always clear this flag */
1761 param->flags &= ~DM_BUFFER_FULL_FLAG;
Peter Rajnoha3abf85b2010-03-06 02:32:31 +00001762 param->flags &= ~DM_UEVENT_GENERATED_FLAG;
Milan Brozf8681202011-03-24 13:54:30 +00001763 param->flags &= ~DM_SECURE_DATA_FLAG;
Mikulas Patockaa2606242013-03-01 22:45:49 +00001764 param->flags &= ~DM_DATA_OUT_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001765
1766 /* Ignores parameters */
1767 if (cmd == DM_REMOVE_ALL_CMD ||
1768 cmd == DM_LIST_DEVICES_CMD ||
1769 cmd == DM_LIST_VERSIONS_CMD)
1770 return 0;
1771
1772 if ((cmd == DM_DEV_CREATE_CMD)) {
1773 if (!*param->name) {
1774 DMWARN("name not supplied when creating device");
1775 return -EINVAL;
1776 }
1777 } else if ((*param->uuid && *param->name)) {
1778 DMWARN("only supply one of name or uuid, cmd(%u)", cmd);
1779 return -EINVAL;
1780 }
1781
1782 /* Ensure strings are terminated */
1783 param->name[DM_NAME_LEN - 1] = '\0';
1784 param->uuid[DM_UUID_LEN - 1] = '\0';
1785
1786 return 0;
1787}
1788
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001789static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001790{
1791 int r = 0;
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001792 int ioctl_flags;
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001793 int param_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001794 unsigned int cmd;
Andrew Mortona26ffd42008-02-08 02:10:16 +00001795 struct dm_ioctl *uninitialized_var(param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001796 ioctl_fn fn = NULL;
Milan Broz6bb43b52011-03-24 13:54:28 +00001797 size_t input_param_size;
Mikulas Patocka02cde502013-03-01 22:45:49 +00001798 struct dm_ioctl param_kernel;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001799
1800 /* only root can play with this */
1801 if (!capable(CAP_SYS_ADMIN))
1802 return -EACCES;
1803
1804 if (_IOC_TYPE(command) != DM_IOCTL)
1805 return -ENOTTY;
1806
1807 cmd = _IOC_NR(command);
1808
1809 /*
1810 * Check the interface version passed in. This also
1811 * writes out the kernel's interface version.
1812 */
1813 r = check_version(cmd, user);
1814 if (r)
1815 return r;
1816
1817 /*
1818 * Nothing more to do for the version command.
1819 */
1820 if (cmd == DM_VERSION_CMD)
1821 return 0;
1822
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001823 fn = lookup_ioctl(cmd, &ioctl_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001824 if (!fn) {
1825 DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
1826 return -ENOTTY;
1827 }
1828
1829 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001830 * Copy the parameters into kernel space.
1831 */
Mikulas Patocka02cde502013-03-01 22:45:49 +00001832 r = copy_params(user, &param_kernel, ioctl_flags, &param, &param_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001833
Alasdair G Kergondab6a422006-02-01 03:04:52 -08001834 if (r)
1835 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001836
Milan Brozf8681202011-03-24 13:54:30 +00001837 input_param_size = param->data_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001838 r = validate_params(cmd, param);
1839 if (r)
1840 goto out;
1841
Linus Torvalds1da177e2005-04-16 15:20:36 -07001842 param->data_size = sizeof(*param);
Milan Broz6bb43b52011-03-24 13:54:28 +00001843 r = fn(param, input_param_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001844
Mikulas Patockae2914cc2013-03-01 22:45:48 +00001845 if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) &&
1846 unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS))
1847 DMERR("ioctl %d tried to output some data but has IOCTL_FLAGS_NO_PARAMS set", cmd);
1848
Linus Torvalds1da177e2005-04-16 15:20:36 -07001849 /*
1850 * Copy the results back to userland.
1851 */
1852 if (!r && copy_to_user(user, param, param->data_size))
1853 r = -EFAULT;
1854
Milan Broz6bb43b52011-03-24 13:54:28 +00001855out:
Mikulas Patocka9c5091f2012-12-21 20:23:36 +00001856 free_params(param, input_param_size, param_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001857 return r;
1858}
1859
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001860static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
1861{
1862 return (long)ctl_ioctl(command, (struct dm_ioctl __user *)u);
1863}
1864
Milan Broz76c072b2008-02-08 02:09:56 +00001865#ifdef CONFIG_COMPAT
1866static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
1867{
1868 return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
1869}
1870#else
1871#define dm_compat_ctl_ioctl NULL
1872#endif
1873
Arjan van de Venfa027c22007-02-12 00:55:33 -08001874static const struct file_operations _ctl_fops = {
Arnd Bergmann402ab352010-08-12 04:13:57 +01001875 .open = nonseekable_open,
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001876 .unlocked_ioctl = dm_ctl_ioctl,
Milan Broz76c072b2008-02-08 02:09:56 +00001877 .compat_ioctl = dm_compat_ctl_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001878 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001879 .llseek = noop_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001880};
1881
1882static struct miscdevice _dm_misc = {
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001883 .minor = MAPPER_CTRL_MINOR,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001884 .name = DM_NAME,
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001885 .nodename = DM_DIR "/" DM_CONTROL_NODE,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001886 .fops = &_ctl_fops
1887};
1888
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001889MODULE_ALIAS_MISCDEV(MAPPER_CTRL_MINOR);
1890MODULE_ALIAS("devname:" DM_DIR "/" DM_CONTROL_NODE);
1891
Linus Torvalds1da177e2005-04-16 15:20:36 -07001892/*
1893 * Create misc character device and link to DM_DIR/control.
1894 */
1895int __init dm_interface_init(void)
1896{
1897 int r;
1898
1899 r = dm_hash_init();
1900 if (r)
1901 return r;
1902
1903 r = misc_register(&_dm_misc);
1904 if (r) {
1905 DMERR("misc_register failed for control device");
1906 dm_hash_exit();
1907 return r;
1908 }
1909
1910 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
1911 DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
1912 DM_DRIVER_EMAIL);
1913 return 0;
1914}
1915
1916void dm_interface_exit(void)
1917{
1918 if (misc_deregister(&_dm_misc) < 0)
1919 DMERR("misc_deregister failed for control device");
1920
1921 dm_hash_exit();
1922}
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001923
1924/**
1925 * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
1926 * @md: Pointer to mapped_device
1927 * @name: Buffer (size DM_NAME_LEN) for name
1928 * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
1929 */
1930int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
1931{
1932 int r = 0;
1933 struct hash_cell *hc;
1934
1935 if (!md)
1936 return -ENXIO;
1937
Mikulas Patocka60769052009-12-10 23:51:52 +00001938 mutex_lock(&dm_hash_cells_mutex);
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001939 hc = dm_get_mdptr(md);
1940 if (!hc || hc->md != md) {
1941 r = -ENXIO;
1942 goto out;
1943 }
1944
Milan Broz23d39f62009-01-06 03:05:04 +00001945 if (name)
1946 strcpy(name, hc->name);
1947 if (uuid)
1948 strcpy(uuid, hc->uuid ? : "");
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001949
1950out:
Mikulas Patocka60769052009-12-10 23:51:52 +00001951 mutex_unlock(&dm_hash_cells_mutex);
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001952
1953 return r;
1954}