blob: 1ce84ed0b765a889b74b94674da2aff4ffe0fd1c [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
Mikulas Patockaba2e19b2011-08-02 12:32:06 +0100131static struct hash_cell *__get_dev_cell(uint64_t dev)
132{
133 struct mapped_device *md;
134 struct hash_cell *hc;
135
136 md = dm_get_md(huge_decode_dev(dev));
137 if (!md)
138 return NULL;
139
140 hc = dm_get_mdptr(md);
141 if (!hc) {
142 dm_put(md);
143 return NULL;
144 }
145
146 return hc;
147}
148
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149/*-----------------------------------------------------------------
150 * Inserting, removing and renaming a device.
151 *---------------------------------------------------------------*/
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152static struct hash_cell *alloc_cell(const char *name, const char *uuid,
153 struct mapped_device *md)
154{
155 struct hash_cell *hc;
156
157 hc = kmalloc(sizeof(*hc), GFP_KERNEL);
158 if (!hc)
159 return NULL;
160
Paulo Marques543537b2005-06-23 00:09:02 -0700161 hc->name = kstrdup(name, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 if (!hc->name) {
163 kfree(hc);
164 return NULL;
165 }
166
167 if (!uuid)
168 hc->uuid = NULL;
169
170 else {
Paulo Marques543537b2005-06-23 00:09:02 -0700171 hc->uuid = kstrdup(uuid, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 if (!hc->uuid) {
173 kfree(hc->name);
174 kfree(hc);
175 return NULL;
176 }
177 }
178
179 INIT_LIST_HEAD(&hc->name_list);
180 INIT_LIST_HEAD(&hc->uuid_list);
181 hc->md = md;
182 hc->new_map = NULL;
183 return hc;
184}
185
186static void free_cell(struct hash_cell *hc)
187{
188 if (hc) {
189 kfree(hc->name);
190 kfree(hc->uuid);
191 kfree(hc);
192 }
193}
194
195/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 * The kdev_t and uuid of a device can never change once it is
197 * initially inserted.
198 */
199static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
200{
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700201 struct hash_cell *cell, *hc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202
203 /*
204 * Allocate the new cells.
205 */
206 cell = alloc_cell(name, uuid, md);
207 if (!cell)
208 return -ENOMEM;
209
210 /*
211 * Insert the cell into both hash tables.
212 */
213 down_write(&_hash_lock);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700214 hc = __get_name_cell(name);
215 if (hc) {
216 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 goto bad;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700218 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219
220 list_add(&cell->name_list, _name_buckets + hash_str(name));
221
222 if (uuid) {
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700223 hc = __get_uuid_cell(uuid);
224 if (hc) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 list_del(&cell->name_list);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700226 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 goto bad;
228 }
229 list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
230 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231 dm_get(md);
Mikulas Patocka60769052009-12-10 23:51:52 +0000232 mutex_lock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 dm_set_mdptr(md, cell);
Mikulas Patocka60769052009-12-10 23:51:52 +0000234 mutex_unlock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235 up_write(&_hash_lock);
236
237 return 0;
238
239 bad:
240 up_write(&_hash_lock);
241 free_cell(cell);
242 return -EBUSY;
243}
244
245static void __hash_remove(struct hash_cell *hc)
246{
goggin, edward269fd2a2005-09-27 21:45:44 -0700247 struct dm_table *table;
248
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 /* remove from the dev hash */
250 list_del(&hc->uuid_list);
251 list_del(&hc->name_list);
Mikulas Patocka60769052009-12-10 23:51:52 +0000252 mutex_lock(&dm_hash_cells_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 dm_set_mdptr(hc->md, NULL);
Mikulas Patocka60769052009-12-10 23:51:52 +0000254 mutex_unlock(&dm_hash_cells_mutex);
goggin, edward269fd2a2005-09-27 21:45:44 -0700255
Alasdair G Kergon7c666412009-12-10 23:52:19 +0000256 table = dm_get_live_table(hc->md);
goggin, edward269fd2a2005-09-27 21:45:44 -0700257 if (table) {
258 dm_table_event(table);
259 dm_table_put(table);
260 }
261
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 if (hc->new_map)
Mikulas Patockad5816872009-01-06 03:05:10 +0000263 dm_table_destroy(hc->new_map);
Mike Anderson1134e5a2006-03-27 01:17:54 -0800264 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 free_cell(hc);
266}
267
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700268static void dm_hash_remove_all(int keep_open_devices)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269{
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100270 int i, dev_skipped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 struct hash_cell *hc;
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100272 struct mapped_device *md;
273
274retry:
275 dev_skipped = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276
277 down_write(&_hash_lock);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700278
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 for (i = 0; i < NUM_BUCKETS; i++) {
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100280 list_for_each_entry(hc, _name_buckets + i, name_list) {
281 md = hc->md;
282 dm_get(md);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700283
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100284 if (keep_open_devices && dm_lock_for_deletion(md)) {
285 dm_put(md);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700286 dev_skipped++;
287 continue;
288 }
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100289
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 __hash_remove(hc);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100291
292 up_write(&_hash_lock);
293
294 dm_put(md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100295 if (likely(keep_open_devices))
296 dm_destroy(md);
297 else
298 dm_destroy_immediate(md);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100299
300 /*
301 * Some mapped devices may be using other mapped
302 * devices, so repeat until we make no further
303 * progress. If a new mapped device is created
304 * here it will also get removed.
305 */
306 goto retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 }
308 }
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700309
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 up_write(&_hash_lock);
Kiyoshi Ueda98f33282010-08-12 04:13:55 +0100311
312 if (dev_skipped)
313 DMWARN("remove_all left %d open device(s)", dev_skipped);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314}
315
Peter Jones84c89552011-01-13 19:59:47 +0000316/*
317 * Set the uuid of a hash_cell that isn't already set.
318 */
319static void __set_cell_uuid(struct hash_cell *hc, char *new_uuid)
320{
321 mutex_lock(&dm_hash_cells_mutex);
322 hc->uuid = new_uuid;
323 mutex_unlock(&dm_hash_cells_mutex);
324
325 list_add(&hc->uuid_list, _uuid_buckets + hash_str(new_uuid));
326}
327
328/*
329 * Changes the name of a hash_cell and returns the old name for
330 * the caller to free.
331 */
332static char *__change_cell_name(struct hash_cell *hc, char *new_name)
333{
334 char *old_name;
335
336 /*
337 * Rename and move the name cell.
338 */
339 list_del(&hc->name_list);
340 old_name = hc->name;
341
342 mutex_lock(&dm_hash_cells_mutex);
343 hc->name = new_name;
344 mutex_unlock(&dm_hash_cells_mutex);
345
346 list_add(&hc->name_list, _name_buckets + hash_str(new_name));
347
348 return old_name;
349}
350
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100351static struct mapped_device *dm_hash_rename(struct dm_ioctl *param,
352 const char *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353{
Peter Jones84c89552011-01-13 19:59:47 +0000354 char *new_data, *old_name = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 struct hash_cell *hc;
goggin, edward81f17772006-01-06 00:20:01 -0800356 struct dm_table *table;
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100357 struct mapped_device *md;
Peter Jones84c89552011-01-13 19:59:47 +0000358 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
360 /*
361 * duplicate new.
362 */
Peter Jones84c89552011-01-13 19:59:47 +0000363 new_data = kstrdup(new, GFP_KERNEL);
364 if (!new_data)
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100365 return ERR_PTR(-ENOMEM);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366
367 down_write(&_hash_lock);
368
369 /*
370 * Is new free ?
371 */
Peter Jones84c89552011-01-13 19:59:47 +0000372 if (change_uuid)
373 hc = __get_uuid_cell(new);
374 else
375 hc = __get_name_cell(new);
376
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 if (hc) {
Peter Jones84c89552011-01-13 19:59:47 +0000378 DMWARN("Unable to change %s on mapped device %s to one that "
379 "already exists: %s",
380 change_uuid ? "uuid" : "name",
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100381 param->name, new);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700382 dm_put(hc->md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 up_write(&_hash_lock);
Peter Jones84c89552011-01-13 19:59:47 +0000384 kfree(new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100385 return ERR_PTR(-EBUSY);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 }
387
388 /*
389 * Is there such a device as 'old' ?
390 */
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100391 hc = __get_name_cell(param->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 if (!hc) {
Peter Jones84c89552011-01-13 19:59:47 +0000393 DMWARN("Unable to rename non-existent device, %s to %s%s",
394 param->name, change_uuid ? "uuid " : "", new);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 up_write(&_hash_lock);
Peter Jones84c89552011-01-13 19:59:47 +0000396 kfree(new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100397 return ERR_PTR(-ENXIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 }
399
400 /*
Peter Jones84c89552011-01-13 19:59:47 +0000401 * Does this device already have a uuid?
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 */
Peter Jones84c89552011-01-13 19:59:47 +0000403 if (change_uuid && hc->uuid) {
404 DMWARN("Unable to change uuid of mapped device %s to %s "
405 "because uuid is already set to %s",
406 param->name, new, hc->uuid);
407 dm_put(hc->md);
408 up_write(&_hash_lock);
409 kfree(new_data);
410 return ERR_PTR(-EINVAL);
411 }
412
413 if (change_uuid)
414 __set_cell_uuid(hc, new_data);
415 else
416 old_name = __change_cell_name(hc, new_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417
goggin, edward81f17772006-01-06 00:20:01 -0800418 /*
419 * Wake up any dm event waiters.
420 */
Alasdair G Kergon7c666412009-12-10 23:52:19 +0000421 table = dm_get_live_table(hc->md);
goggin, edward81f17772006-01-06 00:20:01 -0800422 if (table) {
423 dm_table_event(table);
424 dm_table_put(table);
425 }
426
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100427 if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, param->event_nr))
428 param->flags |= DM_UEVENT_GENERATED_FLAG;
Alasdair G Kergon69267a32007-12-13 14:15:57 +0000429
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100430 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 up_write(&_hash_lock);
432 kfree(old_name);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100433
434 return md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435}
436
437/*-----------------------------------------------------------------
438 * Implementation of the ioctl commands
439 *---------------------------------------------------------------*/
440/*
441 * All the ioctl commands get dispatched to functions with this
442 * prototype.
443 */
444typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size);
445
446static int remove_all(struct dm_ioctl *param, size_t param_size)
447{
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700448 dm_hash_remove_all(1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 param->data_size = 0;
450 return 0;
451}
452
453/*
454 * Round up the ptr to an 8-byte boundary.
455 */
456#define ALIGN_MASK 7
457static inline void *align_ptr(void *ptr)
458{
459 return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK);
460}
461
462/*
463 * Retrieves the data payload buffer from an already allocated
464 * struct dm_ioctl.
465 */
466static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
467 size_t *len)
468{
469 param->data_start = align_ptr(param + 1) - (void *) param;
470
471 if (param->data_start < param_size)
472 *len = param_size - param->data_start;
473 else
474 *len = 0;
475
476 return ((void *) param) + param->data_start;
477}
478
479static int list_devices(struct dm_ioctl *param, size_t param_size)
480{
481 unsigned int i;
482 struct hash_cell *hc;
483 size_t len, needed = 0;
484 struct gendisk *disk;
485 struct dm_name_list *nl, *old_nl = NULL;
486
487 down_write(&_hash_lock);
488
489 /*
490 * Loop through all the devices working out how much
491 * space we need.
492 */
493 for (i = 0; i < NUM_BUCKETS; i++) {
494 list_for_each_entry (hc, _name_buckets + i, name_list) {
495 needed += sizeof(struct dm_name_list);
496 needed += strlen(hc->name) + 1;
497 needed += ALIGN_MASK;
498 }
499 }
500
501 /*
502 * Grab our output buffer.
503 */
504 nl = get_result_buffer(param, param_size, &len);
505 if (len < needed) {
506 param->flags |= DM_BUFFER_FULL_FLAG;
507 goto out;
508 }
509 param->data_size = param->data_start + needed;
510
511 nl->dev = 0; /* Flags no data */
512
513 /*
514 * Now loop through filling out the names.
515 */
516 for (i = 0; i < NUM_BUCKETS; i++) {
517 list_for_each_entry (hc, _name_buckets + i, name_list) {
518 if (old_nl)
519 old_nl->next = (uint32_t) ((void *) nl -
520 (void *) old_nl);
521 disk = dm_disk(hc->md);
Tejun Heof331c022008-09-03 09:01:48 +0200522 nl->dev = huge_encode_dev(disk_devt(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 nl->next = 0;
524 strcpy(nl->name, hc->name);
525
526 old_nl = nl;
527 nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1);
528 }
529 }
530
531 out:
532 up_write(&_hash_lock);
533 return 0;
534}
535
536static void list_version_get_needed(struct target_type *tt, void *needed_param)
537{
538 size_t *needed = needed_param;
539
Alasdair G Kergonc4cc6632005-11-21 21:32:33 -0800540 *needed += sizeof(struct dm_target_versions);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 *needed += strlen(tt->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 *needed += ALIGN_MASK;
543}
544
545static void list_version_get_info(struct target_type *tt, void *param)
546{
547 struct vers_iter *info = param;
548
549 /* Check space - it might have changed since the first iteration */
550 if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 >
551 info->end) {
552
553 info->flags = DM_BUFFER_FULL_FLAG;
554 return;
555 }
556
557 if (info->old_vers)
558 info->old_vers->next = (uint32_t) ((void *)info->vers -
559 (void *)info->old_vers);
560 info->vers->version[0] = tt->version[0];
561 info->vers->version[1] = tt->version[1];
562 info->vers->version[2] = tt->version[2];
563 info->vers->next = 0;
564 strcpy(info->vers->name, tt->name);
565
566 info->old_vers = info->vers;
567 info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
568}
569
570static int list_versions(struct dm_ioctl *param, size_t param_size)
571{
572 size_t len, needed = 0;
573 struct dm_target_versions *vers;
574 struct vers_iter iter_info;
575
576 /*
577 * Loop through all the devices working out how much
578 * space we need.
579 */
580 dm_target_iterate(list_version_get_needed, &needed);
581
582 /*
583 * Grab our output buffer.
584 */
585 vers = get_result_buffer(param, param_size, &len);
586 if (len < needed) {
587 param->flags |= DM_BUFFER_FULL_FLAG;
588 goto out;
589 }
590 param->data_size = param->data_start + needed;
591
592 iter_info.param_size = param_size;
593 iter_info.old_vers = NULL;
594 iter_info.vers = vers;
595 iter_info.flags = 0;
596 iter_info.end = (char *)vers+len;
597
598 /*
599 * Now loop through filling out the names & versions.
600 */
601 dm_target_iterate(list_version_get_info, &iter_info);
602 param->flags |= iter_info.flags;
603
604 out:
605 return 0;
606}
607
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608static int check_name(const char *name)
609{
610 if (strchr(name, '/')) {
611 DMWARN("invalid device name");
612 return -EINVAL;
613 }
614
615 return 0;
616}
617
618/*
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000619 * On successful return, the caller must not attempt to acquire
620 * _hash_lock without first calling dm_table_put, because dm_table_destroy
621 * waits for this dm_table_put and could be called under this lock.
622 */
623static struct dm_table *dm_get_inactive_table(struct mapped_device *md)
624{
625 struct hash_cell *hc;
626 struct dm_table *table = NULL;
627
628 down_read(&_hash_lock);
629 hc = dm_get_mdptr(md);
630 if (!hc || hc->md != md) {
631 DMWARN("device has been removed from the dev hash table.");
632 goto out;
633 }
634
635 table = hc->new_map;
636 if (table)
637 dm_table_get(table);
638
639out:
640 up_read(&_hash_lock);
641
642 return table;
643}
644
645static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md,
646 struct dm_ioctl *param)
647{
648 return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ?
649 dm_get_inactive_table(md) : dm_get_live_table(md);
650}
651
652/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653 * Fills in a dm_ioctl structure, ready for sending back to
654 * userland.
655 */
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100656static void __dev_status(struct mapped_device *md, struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657{
658 struct gendisk *disk = dm_disk(md);
659 struct dm_table *table;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660
661 param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
662 DM_ACTIVE_PRESENT_FLAG);
663
Kiyoshi Ueda4f186f82009-12-10 23:52:26 +0000664 if (dm_suspended_md(md))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665 param->flags |= DM_SUSPEND_FLAG;
666
Tejun Heof331c022008-09-03 09:01:48 +0200667 param->dev = huge_encode_dev(disk_devt(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700669 /*
670 * Yes, this will be out of date by the time it gets back
671 * to userland, but it is still very useful for
672 * debugging.
673 */
674 param->open_count = dm_open_count(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 param->event_nr = dm_get_event_nr(md);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000677 param->target_count = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678
Alasdair G Kergon7c666412009-12-10 23:52:19 +0000679 table = dm_get_live_table(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 if (table) {
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000681 if (!(param->flags & DM_QUERY_INACTIVE_TABLE_FLAG)) {
682 if (get_disk_ro(disk))
683 param->flags |= DM_READONLY_FLAG;
684 param->target_count = dm_table_get_num_targets(table);
685 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 dm_table_put(table);
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +0000687
688 param->flags |= DM_ACTIVE_PRESENT_FLAG;
689 }
690
691 if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) {
692 table = dm_get_inactive_table(md);
693 if (table) {
694 if (!(dm_table_get_mode(table) & FMODE_WRITE))
695 param->flags |= DM_READONLY_FLAG;
696 param->target_count = dm_table_get_num_targets(table);
697 dm_table_put(table);
698 }
699 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700}
701
702static int dev_create(struct dm_ioctl *param, size_t param_size)
703{
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700704 int r, m = DM_ANY_MINOR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705 struct mapped_device *md;
706
707 r = check_name(param->name);
708 if (r)
709 return r;
710
711 if (param->flags & DM_PERSISTENT_DEV_FLAG)
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700712 m = MINOR(huge_decode_dev(param->dev));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713
Alasdair G Kergon2b06cff2006-06-26 00:27:32 -0700714 r = dm_create(m, &md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715 if (r)
716 return r;
717
718 r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100719 if (r) {
720 dm_put(md);
721 dm_destroy(md);
722 return r;
723 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724
725 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
726
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100727 __dev_status(md, param);
728
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 dm_put(md);
730
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100731 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732}
733
734/*
735 * Always use UUID for lookups if it's present, otherwise use name or dev.
736 */
Arjan van de Ven858119e2006-01-14 13:20:43 -0800737static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738{
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100739 struct hash_cell *hc = NULL;
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800740
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100741 if (*param->uuid) {
Mikulas Patocka759dea22011-08-02 12:32:06 +0100742 if (*param->name || param->dev)
743 return NULL;
744
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100745 hc = __get_uuid_cell(param->uuid);
746 if (!hc)
747 return NULL;
Mikulas Patockaba2e19b2011-08-02 12:32:06 +0100748 } else if (*param->name) {
Mikulas Patocka759dea22011-08-02 12:32:06 +0100749 if (param->dev)
750 return NULL;
751
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100752 hc = __get_name_cell(param->name);
753 if (!hc)
754 return NULL;
Mikulas Patockaba2e19b2011-08-02 12:32:06 +0100755 } else if (param->dev) {
756 hc = __get_dev_cell(param->dev);
757 if (!hc)
758 return NULL;
759 } else
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100760 return NULL;
Alasdair G Kergon9ade92a2006-03-27 01:17:53 -0800761
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100762 /*
763 * Sneakily write in both the name and the uuid
764 * while we have the cell.
765 */
766 strlcpy(param->name, hc->name, sizeof(param->name));
767 if (hc->uuid)
768 strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
769 else
770 param->uuid[0] = '\0';
771
772 if (hc->new_map)
773 param->flags |= DM_INACTIVE_PRESENT_FLAG;
774 else
775 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
776
777 return hc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778}
779
Arjan van de Ven858119e2006-01-14 13:20:43 -0800780static struct mapped_device *find_device(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781{
782 struct hash_cell *hc;
783 struct mapped_device *md = NULL;
784
785 down_read(&_hash_lock);
786 hc = __find_device_hash_cell(param);
Mikulas Patocka0ddf9642011-08-02 12:32:06 +0100787 if (hc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 up_read(&_hash_lock);
790
791 return md;
792}
793
794static int dev_remove(struct dm_ioctl *param, size_t param_size)
795{
796 struct hash_cell *hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700797 struct mapped_device *md;
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700798 int r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799
800 down_write(&_hash_lock);
801 hc = __find_device_hash_cell(param);
802
803 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +0000804 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 up_write(&_hash_lock);
806 return -ENXIO;
807 }
808
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700809 md = hc->md;
810
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700811 /*
812 * Ensure the device is not open and nothing further can open it.
813 */
814 r = dm_lock_for_deletion(md);
815 if (r) {
Milan Broz810b4922011-01-13 19:59:55 +0000816 DMDEBUG_LIMIT("unable to remove open device %s", hc->name);
Alasdair G Kergon5c6bd752006-06-26 00:27:34 -0700817 up_write(&_hash_lock);
818 dm_put(md);
819 return r;
820 }
821
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822 __hash_remove(hc);
823 up_write(&_hash_lock);
Milan Broz60935eb2009-06-22 10:12:30 +0100824
Peter Rajnoha3abf85b2010-03-06 02:32:31 +0000825 if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr))
826 param->flags |= DM_UEVENT_GENERATED_FLAG;
Milan Broz60935eb2009-06-22 10:12:30 +0100827
Jeff Mahoney7ec75f22006-06-26 00:27:24 -0700828 dm_put(md);
Kiyoshi Ueda3f77316d2010-08-12 04:13:56 +0100829 dm_destroy(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830 return 0;
831}
832
833/*
834 * Check a string doesn't overrun the chunk of
835 * memory we copied from userland.
836 */
837static int invalid_str(char *str, void *end)
838{
839 while ((void *) str < end)
840 if (!*str++)
841 return 0;
842
843 return -EINVAL;
844}
845
846static int dev_rename(struct dm_ioctl *param, size_t param_size)
847{
848 int r;
Peter Jones84c89552011-01-13 19:59:47 +0000849 char *new_data = (char *) param + param->data_start;
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100850 struct mapped_device *md;
Peter Jones84c89552011-01-13 19:59:47 +0000851 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852
Peter Jones84c89552011-01-13 19:59:47 +0000853 if (new_data < param->data ||
854 invalid_str(new_data, (void *) param + param_size) ||
855 strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) {
856 DMWARN("Invalid new mapped device name or uuid string supplied.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700857 return -EINVAL;
858 }
859
Peter Jones84c89552011-01-13 19:59:47 +0000860 if (!change_uuid) {
861 r = check_name(new_data);
862 if (r)
863 return r;
864 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865
Peter Jones84c89552011-01-13 19:59:47 +0000866 md = dm_hash_rename(param, new_data);
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100867 if (IS_ERR(md))
868 return PTR_ERR(md);
Peter Rajnoha3abf85b2010-03-06 02:32:31 +0000869
Peter Rajnoha856a6f12010-08-12 04:13:53 +0100870 __dev_status(md, param);
871 dm_put(md);
872
873 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874}
875
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800876static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
877{
878 int r = -EINVAL, x;
879 struct mapped_device *md;
880 struct hd_geometry geometry;
881 unsigned long indata[4];
882 char *geostr = (char *) param + param->data_start;
883
884 md = find_device(param);
885 if (!md)
886 return -ENXIO;
887
Alasdair G Kergon27238b22008-02-08 02:09:53 +0000888 if (geostr < param->data ||
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800889 invalid_str(geostr, (void *) param + param_size)) {
890 DMWARN("Invalid geometry supplied.");
891 goto out;
892 }
893
894 x = sscanf(geostr, "%lu %lu %lu %lu", indata,
895 indata + 1, indata + 2, indata + 3);
896
897 if (x != 4) {
898 DMWARN("Unable to interpret geometry settings.");
899 goto out;
900 }
901
902 if (indata[0] > 65535 || indata[1] > 255 ||
903 indata[2] > 255 || indata[3] > ULONG_MAX) {
904 DMWARN("Geometry exceeds range limits.");
905 goto out;
906 }
907
908 geometry.cylinders = indata[0];
909 geometry.heads = indata[1];
910 geometry.sectors = indata[2];
911 geometry.start = indata[3];
912
913 r = dm_set_geometry(md, &geometry);
Darrick J. Wong3ac51e72006-03-27 01:17:54 -0800914
915 param->data_size = 0;
916
917out:
918 dm_put(md);
919 return r;
920}
921
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922static int do_suspend(struct dm_ioctl *param)
923{
924 int r = 0;
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800925 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 struct mapped_device *md;
927
928 md = find_device(param);
929 if (!md)
930 return -ENXIO;
931
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800932 if (param->flags & DM_SKIP_LOCKFS_FLAG)
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800933 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
Kiyoshi Ueda81fdb092006-12-08 02:41:07 -0800934 if (param->flags & DM_NOFLUSH_FLAG)
935 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800936
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100937 if (!dm_suspended_md(md)) {
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800938 r = dm_suspend(md, suspend_flags);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100939 if (r)
940 goto out;
941 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100943 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100945out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +0100947
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948 return r;
949}
950
951static int do_resume(struct dm_ioctl *param)
952{
953 int r = 0;
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800954 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955 struct hash_cell *hc;
956 struct mapped_device *md;
Alasdair G Kergon042d2a92009-12-10 23:52:24 +0000957 struct dm_table *new_map, *old_map = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700958
959 down_write(&_hash_lock);
960
961 hc = __find_device_hash_cell(param);
962 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +0000963 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964 up_write(&_hash_lock);
965 return -ENXIO;
966 }
967
968 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700969
970 new_map = hc->new_map;
971 hc->new_map = NULL;
972 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
973
974 up_write(&_hash_lock);
975
976 /* Do we need to load a new map ? */
977 if (new_map) {
978 /* Suspend if it isn't already suspended */
Alasdair G Kergon6da487d2006-01-06 00:20:07 -0800979 if (param->flags & DM_SKIP_LOCKFS_FLAG)
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800980 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
Kiyoshi Ueda81fdb092006-12-08 02:41:07 -0800981 if (param->flags & DM_NOFLUSH_FLAG)
982 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
Kiyoshi Ueda4f186f82009-12-10 23:52:26 +0000983 if (!dm_suspended_md(md))
Kiyoshi Uedaa3d77d32006-12-08 02:41:04 -0800984 dm_suspend(md, suspend_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700985
Alasdair G Kergon042d2a92009-12-10 23:52:24 +0000986 old_map = dm_swap_table(md, new_map);
987 if (IS_ERR(old_map)) {
Mikulas Patockad5816872009-01-06 03:05:10 +0000988 dm_table_destroy(new_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989 dm_put(md);
Alasdair G Kergon042d2a92009-12-10 23:52:24 +0000990 return PTR_ERR(old_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 }
992
993 if (dm_table_get_mode(new_map) & FMODE_WRITE)
994 set_disk_ro(dm_disk(md), 0);
995 else
996 set_disk_ro(dm_disk(md), 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 }
998
Mike Snitzer0f3649a2010-03-06 02:32:24 +0000999 if (dm_suspended_md(md)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000 r = dm_resume(md);
Peter Rajnoha3abf85b2010-03-06 02:32:31 +00001001 if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
1002 param->flags |= DM_UEVENT_GENERATED_FLAG;
Mike Snitzer0f3649a2010-03-06 02:32:24 +00001003 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004
Alasdair G Kergon042d2a92009-12-10 23:52:24 +00001005 if (old_map)
1006 dm_table_destroy(old_map);
Milan Broz60935eb2009-06-22 10:12:30 +01001007
Mike Snitzer0f3649a2010-03-06 02:32:24 +00001008 if (!r)
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001009 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010
1011 dm_put(md);
1012 return r;
1013}
1014
1015/*
1016 * Set or unset the suspension state of a device.
1017 * If the device already is in the requested state we just return its status.
1018 */
1019static int dev_suspend(struct dm_ioctl *param, size_t param_size)
1020{
1021 if (param->flags & DM_SUSPEND_FLAG)
1022 return do_suspend(param);
1023
1024 return do_resume(param);
1025}
1026
1027/*
1028 * Copies device info back to user space, used by
1029 * the create and info ioctls.
1030 */
1031static int dev_status(struct dm_ioctl *param, size_t param_size)
1032{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033 struct mapped_device *md;
1034
1035 md = find_device(param);
1036 if (!md)
1037 return -ENXIO;
1038
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001039 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001041
1042 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043}
1044
1045/*
1046 * Build up the status struct for each target
1047 */
1048static void retrieve_status(struct dm_table *table,
1049 struct dm_ioctl *param, size_t param_size)
1050{
1051 unsigned int i, num_targets;
1052 struct dm_target_spec *spec;
1053 char *outbuf, *outptr;
1054 status_type_t type;
1055 size_t remaining, len, used = 0;
1056
1057 outptr = outbuf = get_result_buffer(param, param_size, &len);
1058
1059 if (param->flags & DM_STATUS_TABLE_FLAG)
1060 type = STATUSTYPE_TABLE;
1061 else
1062 type = STATUSTYPE_INFO;
1063
1064 /* Get all the target info */
1065 num_targets = dm_table_get_num_targets(table);
1066 for (i = 0; i < num_targets; i++) {
1067 struct dm_target *ti = dm_table_get_target(table, i);
1068
1069 remaining = len - (outptr - outbuf);
1070 if (remaining <= sizeof(struct dm_target_spec)) {
1071 param->flags |= DM_BUFFER_FULL_FLAG;
1072 break;
1073 }
1074
1075 spec = (struct dm_target_spec *) outptr;
1076
1077 spec->status = 0;
1078 spec->sector_start = ti->begin;
1079 spec->length = ti->len;
1080 strncpy(spec->target_type, ti->type->name,
1081 sizeof(spec->target_type));
1082
1083 outptr += sizeof(struct dm_target_spec);
1084 remaining = len - (outptr - outbuf);
1085 if (remaining <= 0) {
1086 param->flags |= DM_BUFFER_FULL_FLAG;
1087 break;
1088 }
1089
1090 /* Get the status/table string from the target driver */
1091 if (ti->type->status) {
1092 if (ti->type->status(ti, type, outptr, remaining)) {
1093 param->flags |= DM_BUFFER_FULL_FLAG;
1094 break;
1095 }
1096 } else
1097 outptr[0] = '\0';
1098
1099 outptr += strlen(outptr) + 1;
1100 used = param->data_start + (outptr - outbuf);
1101
1102 outptr = align_ptr(outptr);
1103 spec->next = outptr - outbuf;
1104 }
1105
1106 if (used)
1107 param->data_size = used;
1108
1109 param->target_count = num_targets;
1110}
1111
1112/*
1113 * Wait for a device to report an event
1114 */
1115static int dev_wait(struct dm_ioctl *param, size_t param_size)
1116{
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001117 int r = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118 struct mapped_device *md;
1119 struct dm_table *table;
1120
1121 md = find_device(param);
1122 if (!md)
1123 return -ENXIO;
1124
1125 /*
1126 * Wait for a notification event
1127 */
1128 if (dm_wait_event(md, param->event_nr)) {
1129 r = -ERESTARTSYS;
1130 goto out;
1131 }
1132
1133 /*
1134 * The userland program is going to want to know what
1135 * changed to trigger the event, so we may as well tell
1136 * him and save an ioctl.
1137 */
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001138 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +00001140 table = dm_get_live_or_inactive_table(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141 if (table) {
1142 retrieve_status(table, param, param_size);
1143 dm_table_put(table);
1144 }
1145
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001146out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001147 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001148
Linus Torvalds1da177e2005-04-16 15:20:36 -07001149 return r;
1150}
1151
Al Viroaeb5d722008-09-02 15:28:45 -04001152static inline fmode_t get_mode(struct dm_ioctl *param)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153{
Al Viroaeb5d722008-09-02 15:28:45 -04001154 fmode_t mode = FMODE_READ | FMODE_WRITE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155
1156 if (param->flags & DM_READONLY_FLAG)
1157 mode = FMODE_READ;
1158
1159 return mode;
1160}
1161
1162static int next_target(struct dm_target_spec *last, uint32_t next, void *end,
1163 struct dm_target_spec **spec, char **target_params)
1164{
1165 *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
1166 *target_params = (char *) (*spec + 1);
1167
1168 if (*spec < (last + 1))
1169 return -EINVAL;
1170
1171 return invalid_str(*target_params, end);
1172}
1173
1174static int populate_table(struct dm_table *table,
1175 struct dm_ioctl *param, size_t param_size)
1176{
1177 int r;
1178 unsigned int i = 0;
1179 struct dm_target_spec *spec = (struct dm_target_spec *) param;
1180 uint32_t next = param->data_start;
1181 void *end = (void *) param + param_size;
1182 char *target_params;
1183
1184 if (!param->target_count) {
1185 DMWARN("populate_table: no targets specified");
1186 return -EINVAL;
1187 }
1188
1189 for (i = 0; i < param->target_count; i++) {
1190
1191 r = next_target(spec, next, end, &spec, &target_params);
1192 if (r) {
1193 DMWARN("unable to find target");
1194 return r;
1195 }
1196
1197 r = dm_table_add_target(table, spec->target_type,
1198 (sector_t) spec->sector_start,
1199 (sector_t) spec->length,
1200 target_params);
1201 if (r) {
1202 DMWARN("error adding target to table");
1203 return r;
1204 }
1205
1206 next = spec->next;
1207 }
1208
1209 return dm_table_complete(table);
1210}
1211
1212static int table_load(struct dm_ioctl *param, size_t param_size)
1213{
1214 int r;
1215 struct hash_cell *hc;
1216 struct dm_table *t;
Mike Anderson1134e5a2006-03-27 01:17:54 -08001217 struct mapped_device *md;
Alasdair G Kergon36a04562011-10-31 20:19:04 +00001218 struct target_type *immutable_target_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001219
Mike Anderson1134e5a2006-03-27 01:17:54 -08001220 md = find_device(param);
1221 if (!md)
1222 return -ENXIO;
1223
1224 r = dm_table_create(&t, get_mode(param), param->target_count, md);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225 if (r)
Mike Anderson1134e5a2006-03-27 01:17:54 -08001226 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227
1228 r = populate_table(t, param, param_size);
1229 if (r) {
Mikulas Patockaf80a5572009-03-16 17:44:26 +00001230 dm_table_destroy(t);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001231 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001232 }
1233
Alasdair G Kergon36a04562011-10-31 20:19:04 +00001234 immutable_target_type = dm_get_immutable_target_type(md);
1235 if (immutable_target_type &&
1236 (immutable_target_type != dm_table_get_immutable_target_type(t))) {
1237 DMWARN("can't replace immutable target type %s",
1238 immutable_target_type->name);
1239 dm_table_destroy(t);
1240 r = -EINVAL;
1241 goto out;
1242 }
1243
Mike Snitzer4a0b4dd2010-08-12 04:14:02 +01001244 /* Protect md->type and md->queue against concurrent table loads. */
Mike Snitzera5664da2010-08-12 04:14:01 +01001245 dm_lock_md_type(md);
1246 if (dm_get_md_type(md) == DM_TYPE_NONE)
1247 /* Initial table load: acquire type of table. */
1248 dm_set_md_type(md, dm_table_get_type(t));
1249 else if (dm_get_md_type(md) != dm_table_get_type(t)) {
1250 DMWARN("can't change device type after initial table load.");
1251 dm_table_destroy(t);
1252 dm_unlock_md_type(md);
1253 r = -EINVAL;
1254 goto out;
1255 }
Mike Snitzer4a0b4dd2010-08-12 04:14:02 +01001256
1257 /* setup md->queue to reflect md's type (may block) */
1258 r = dm_setup_md_queue(md);
1259 if (r) {
1260 DMWARN("unable to set up device queue for new table.");
1261 dm_table_destroy(t);
1262 dm_unlock_md_type(md);
1263 goto out;
1264 }
Mike Snitzera5664da2010-08-12 04:14:01 +01001265 dm_unlock_md_type(md);
1266
1267 /* stage inactive table */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001268 down_write(&_hash_lock);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001269 hc = dm_get_mdptr(md);
1270 if (!hc || hc->md != md) {
1271 DMWARN("device has been removed from the dev hash table.");
Mikulas Patockaf80a5572009-03-16 17:44:26 +00001272 dm_table_destroy(t);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001273 up_write(&_hash_lock);
1274 r = -ENXIO;
1275 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001276 }
1277
1278 if (hc->new_map)
Mikulas Patockad5816872009-01-06 03:05:10 +00001279 dm_table_destroy(hc->new_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001280 hc->new_map = t;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281 up_write(&_hash_lock);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001282
1283 param->flags |= DM_INACTIVE_PRESENT_FLAG;
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001284 __dev_status(md, param);
Mike Anderson1134e5a2006-03-27 01:17:54 -08001285
1286out:
1287 dm_put(md);
1288
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289 return r;
1290}
1291
1292static int table_clear(struct dm_ioctl *param, size_t param_size)
1293{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294 struct hash_cell *hc;
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001295 struct mapped_device *md;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296
1297 down_write(&_hash_lock);
1298
1299 hc = __find_device_hash_cell(param);
1300 if (!hc) {
Milan Broz810b4922011-01-13 19:59:55 +00001301 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001302 up_write(&_hash_lock);
1303 return -ENXIO;
1304 }
1305
1306 if (hc->new_map) {
Mikulas Patockad5816872009-01-06 03:05:10 +00001307 dm_table_destroy(hc->new_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308 hc->new_map = NULL;
1309 }
1310
1311 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1312
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001313 __dev_status(hc->md, param);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001314 md = hc->md;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001315 up_write(&_hash_lock);
Jeff Mahoney7ec75f22006-06-26 00:27:24 -07001316 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001317
1318 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001319}
1320
1321/*
1322 * Retrieves a list of devices used by a particular dm device.
1323 */
1324static void retrieve_deps(struct dm_table *table,
1325 struct dm_ioctl *param, size_t param_size)
1326{
1327 unsigned int count = 0;
1328 struct list_head *tmp;
1329 size_t len, needed;
Mikulas Patocka82b15192008-10-10 13:37:09 +01001330 struct dm_dev_internal *dd;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331 struct dm_target_deps *deps;
1332
1333 deps = get_result_buffer(param, param_size, &len);
1334
1335 /*
1336 * Count the devices.
1337 */
1338 list_for_each (tmp, dm_table_get_devices(table))
1339 count++;
1340
1341 /*
1342 * Check we have enough space.
1343 */
1344 needed = sizeof(*deps) + (sizeof(*deps->dev) * count);
1345 if (len < needed) {
1346 param->flags |= DM_BUFFER_FULL_FLAG;
1347 return;
1348 }
1349
1350 /*
1351 * Fill in the devices.
1352 */
1353 deps->count = count;
1354 count = 0;
1355 list_for_each_entry (dd, dm_table_get_devices(table), list)
Mikulas Patocka82b15192008-10-10 13:37:09 +01001356 deps->dev[count++] = huge_encode_dev(dd->dm_dev.bdev->bd_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001357
1358 param->data_size = param->data_start + needed;
1359}
1360
1361static int table_deps(struct dm_ioctl *param, size_t param_size)
1362{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 struct mapped_device *md;
1364 struct dm_table *table;
1365
1366 md = find_device(param);
1367 if (!md)
1368 return -ENXIO;
1369
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001370 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001371
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +00001372 table = dm_get_live_or_inactive_table(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373 if (table) {
1374 retrieve_deps(table, param, param_size);
1375 dm_table_put(table);
1376 }
1377
Linus Torvalds1da177e2005-04-16 15:20:36 -07001378 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001379
1380 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001381}
1382
1383/*
1384 * Return the status of a device as a text string for each
1385 * target.
1386 */
1387static int table_status(struct dm_ioctl *param, size_t param_size)
1388{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389 struct mapped_device *md;
1390 struct dm_table *table;
1391
1392 md = find_device(param);
1393 if (!md)
1394 return -ENXIO;
1395
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001396 __dev_status(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397
Mike Snitzer1d0f3ce2009-12-10 23:52:22 +00001398 table = dm_get_live_or_inactive_table(md, param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001399 if (table) {
1400 retrieve_status(table, param, param_size);
1401 dm_table_put(table);
1402 }
1403
Linus Torvalds1da177e2005-04-16 15:20:36 -07001404 dm_put(md);
Alasdair G Kergon094ea9a2010-08-12 04:13:52 +01001405
1406 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407}
1408
1409/*
1410 * Pass a message to the target that's at the supplied device offset.
1411 */
1412static int target_message(struct dm_ioctl *param, size_t param_size)
1413{
1414 int r, argc;
1415 char **argv;
1416 struct mapped_device *md;
1417 struct dm_table *table;
1418 struct dm_target *ti;
1419 struct dm_target_msg *tmsg = (void *) param + param->data_start;
1420
1421 md = find_device(param);
1422 if (!md)
1423 return -ENXIO;
1424
Milan Broz027d50f2007-10-19 22:38:36 +01001425 if (tmsg < (struct dm_target_msg *) param->data ||
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426 invalid_str(tmsg->message, (void *) param + param_size)) {
1427 DMWARN("Invalid target message parameters.");
1428 r = -EINVAL;
1429 goto out;
1430 }
1431
1432 r = dm_split_args(&argc, &argv, tmsg->message);
1433 if (r) {
1434 DMWARN("Failed to split target message parameters");
1435 goto out;
1436 }
1437
Alasdair G Kergon2ca4c922011-08-02 12:32:03 +01001438 if (!argc) {
1439 DMWARN("Empty message received.");
Jesper Juhl902c6a92012-03-07 19:09:34 +00001440 goto out_argv;
Alasdair G Kergon2ca4c922011-08-02 12:32:03 +01001441 }
1442
Alasdair G Kergon7c666412009-12-10 23:52:19 +00001443 table = dm_get_live_table(md);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001444 if (!table)
1445 goto out_argv;
1446
Mike Andersonc50abeb2009-12-10 23:52:20 +00001447 if (dm_deleting_md(md)) {
1448 r = -ENXIO;
1449 goto out_table;
1450 }
1451
Jun'ichi Nomura512875b2007-12-13 14:15:25 +00001452 ti = dm_table_find_target(table, tmsg->sector);
1453 if (!dm_target_is_valid(ti)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 DMWARN("Target message sector outside device.");
1455 r = -EINVAL;
Jun'ichi Nomura512875b2007-12-13 14:15:25 +00001456 } else if (ti->type->message)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457 r = ti->type->message(ti, argc, argv);
1458 else {
1459 DMWARN("Target type does not support messages");
1460 r = -EINVAL;
1461 }
1462
Mike Andersonc50abeb2009-12-10 23:52:20 +00001463 out_table:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001464 dm_table_put(table);
1465 out_argv:
1466 kfree(argv);
1467 out:
1468 param->data_size = 0;
1469 dm_put(md);
1470 return r;
1471}
1472
1473/*-----------------------------------------------------------------
1474 * Implementation of open/close/ioctl on the special char
1475 * device.
1476 *---------------------------------------------------------------*/
1477static ioctl_fn lookup_ioctl(unsigned int cmd)
1478{
1479 static struct {
1480 int cmd;
1481 ioctl_fn fn;
1482 } _ioctls[] = {
1483 {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */
1484 {DM_REMOVE_ALL_CMD, remove_all},
1485 {DM_LIST_DEVICES_CMD, list_devices},
1486
1487 {DM_DEV_CREATE_CMD, dev_create},
1488 {DM_DEV_REMOVE_CMD, dev_remove},
1489 {DM_DEV_RENAME_CMD, dev_rename},
1490 {DM_DEV_SUSPEND_CMD, dev_suspend},
1491 {DM_DEV_STATUS_CMD, dev_status},
1492 {DM_DEV_WAIT_CMD, dev_wait},
1493
1494 {DM_TABLE_LOAD_CMD, table_load},
1495 {DM_TABLE_CLEAR_CMD, table_clear},
1496 {DM_TABLE_DEPS_CMD, table_deps},
1497 {DM_TABLE_STATUS_CMD, table_status},
1498
1499 {DM_LIST_VERSIONS_CMD, list_versions},
1500
Darrick J. Wong3ac51e72006-03-27 01:17:54 -08001501 {DM_TARGET_MSG_CMD, target_message},
1502 {DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001503 };
1504
1505 return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn;
1506}
1507
1508/*
1509 * As well as checking the version compatibility this always
1510 * copies the kernel interface version out.
1511 */
1512static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
1513{
1514 uint32_t version[3];
1515 int r = 0;
1516
1517 if (copy_from_user(version, user->version, sizeof(version)))
1518 return -EFAULT;
1519
1520 if ((DM_VERSION_MAJOR != version[0]) ||
1521 (DM_VERSION_MINOR < version[1])) {
1522 DMWARN("ioctl interface mismatch: "
1523 "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1524 DM_VERSION_MAJOR, DM_VERSION_MINOR,
1525 DM_VERSION_PATCHLEVEL,
1526 version[0], version[1], version[2], cmd);
1527 r = -EINVAL;
1528 }
1529
1530 /*
1531 * Fill in the kernel version.
1532 */
1533 version[0] = DM_VERSION_MAJOR;
1534 version[1] = DM_VERSION_MINOR;
1535 version[2] = DM_VERSION_PATCHLEVEL;
1536 if (copy_to_user(user->version, version, sizeof(version)))
1537 return -EFAULT;
1538
1539 return r;
1540}
1541
Linus Torvalds1da177e2005-04-16 15:20:36 -07001542static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
1543{
1544 struct dm_ioctl tmp, *dmi;
Milan Brozf8681202011-03-24 13:54:30 +00001545 int secure_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546
Milan Broz76c072b2008-02-08 02:09:56 +00001547 if (copy_from_user(&tmp, user, sizeof(tmp) - sizeof(tmp.data)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001548 return -EFAULT;
1549
Milan Broz76c072b2008-02-08 02:09:56 +00001550 if (tmp.data_size < (sizeof(tmp) - sizeof(tmp.data)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551 return -EINVAL;
1552
Milan Brozf8681202011-03-24 13:54:30 +00001553 secure_data = tmp.flags & DM_SECURE_DATA_FLAG;
1554
Jesper Juhlbb56acf2007-10-19 22:38:54 +01001555 dmi = vmalloc(tmp.data_size);
Milan Brozf8681202011-03-24 13:54:30 +00001556 if (!dmi) {
1557 if (secure_data && clear_user(user, tmp.data_size))
1558 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001559 return -ENOMEM;
Milan Brozf8681202011-03-24 13:54:30 +00001560 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001561
Milan Broz6bb43b52011-03-24 13:54:28 +00001562 if (copy_from_user(dmi, user, tmp.data_size))
1563 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001564
Milan Brozf8681202011-03-24 13:54:30 +00001565 /* Wipe the user buffer so we do not return it to userspace */
1566 if (secure_data && clear_user(user, tmp.data_size))
1567 goto bad;
1568
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569 *param = dmi;
1570 return 0;
Milan Broz6bb43b52011-03-24 13:54:28 +00001571
1572bad:
Milan Brozf8681202011-03-24 13:54:30 +00001573 if (secure_data)
1574 memset(dmi, 0, tmp.data_size);
Milan Broz6bb43b52011-03-24 13:54:28 +00001575 vfree(dmi);
1576 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001577}
1578
1579static int validate_params(uint cmd, struct dm_ioctl *param)
1580{
1581 /* Always clear this flag */
1582 param->flags &= ~DM_BUFFER_FULL_FLAG;
Peter Rajnoha3abf85b2010-03-06 02:32:31 +00001583 param->flags &= ~DM_UEVENT_GENERATED_FLAG;
Milan Brozf8681202011-03-24 13:54:30 +00001584 param->flags &= ~DM_SECURE_DATA_FLAG;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001585
1586 /* Ignores parameters */
1587 if (cmd == DM_REMOVE_ALL_CMD ||
1588 cmd == DM_LIST_DEVICES_CMD ||
1589 cmd == DM_LIST_VERSIONS_CMD)
1590 return 0;
1591
1592 if ((cmd == DM_DEV_CREATE_CMD)) {
1593 if (!*param->name) {
1594 DMWARN("name not supplied when creating device");
1595 return -EINVAL;
1596 }
1597 } else if ((*param->uuid && *param->name)) {
1598 DMWARN("only supply one of name or uuid, cmd(%u)", cmd);
1599 return -EINVAL;
1600 }
1601
1602 /* Ensure strings are terminated */
1603 param->name[DM_NAME_LEN - 1] = '\0';
1604 param->uuid[DM_UUID_LEN - 1] = '\0';
1605
1606 return 0;
1607}
1608
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001609static int ctl_ioctl(uint command, struct dm_ioctl __user *user)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001610{
1611 int r = 0;
Milan Brozf8681202011-03-24 13:54:30 +00001612 int wipe_buffer;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001613 unsigned int cmd;
Andrew Mortona26ffd42008-02-08 02:10:16 +00001614 struct dm_ioctl *uninitialized_var(param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001615 ioctl_fn fn = NULL;
Milan Broz6bb43b52011-03-24 13:54:28 +00001616 size_t input_param_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001617
1618 /* only root can play with this */
1619 if (!capable(CAP_SYS_ADMIN))
1620 return -EACCES;
1621
1622 if (_IOC_TYPE(command) != DM_IOCTL)
1623 return -ENOTTY;
1624
1625 cmd = _IOC_NR(command);
1626
1627 /*
1628 * Check the interface version passed in. This also
1629 * writes out the kernel's interface version.
1630 */
1631 r = check_version(cmd, user);
1632 if (r)
1633 return r;
1634
1635 /*
1636 * Nothing more to do for the version command.
1637 */
1638 if (cmd == DM_VERSION_CMD)
1639 return 0;
1640
1641 fn = lookup_ioctl(cmd);
1642 if (!fn) {
1643 DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
1644 return -ENOTTY;
1645 }
1646
1647 /*
1648 * Trying to avoid low memory issues when a device is
1649 * suspended.
1650 */
1651 current->flags |= PF_MEMALLOC;
1652
1653 /*
1654 * Copy the parameters into kernel space.
1655 */
1656 r = copy_params(user, &param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657
Alasdair G Kergondab6a422006-02-01 03:04:52 -08001658 current->flags &= ~PF_MEMALLOC;
1659
1660 if (r)
1661 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001662
Milan Brozf8681202011-03-24 13:54:30 +00001663 input_param_size = param->data_size;
1664 wipe_buffer = param->flags & DM_SECURE_DATA_FLAG;
1665
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666 r = validate_params(cmd, param);
1667 if (r)
1668 goto out;
1669
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670 param->data_size = sizeof(*param);
Milan Broz6bb43b52011-03-24 13:54:28 +00001671 r = fn(param, input_param_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001672
1673 /*
1674 * Copy the results back to userland.
1675 */
1676 if (!r && copy_to_user(user, param, param->data_size))
1677 r = -EFAULT;
1678
Milan Broz6bb43b52011-03-24 13:54:28 +00001679out:
Milan Brozf8681202011-03-24 13:54:30 +00001680 if (wipe_buffer)
1681 memset(param, 0, input_param_size);
1682
Milan Broz6bb43b52011-03-24 13:54:28 +00001683 vfree(param);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001684 return r;
1685}
1686
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001687static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
1688{
1689 return (long)ctl_ioctl(command, (struct dm_ioctl __user *)u);
1690}
1691
Milan Broz76c072b2008-02-08 02:09:56 +00001692#ifdef CONFIG_COMPAT
1693static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
1694{
1695 return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
1696}
1697#else
1698#define dm_compat_ctl_ioctl NULL
1699#endif
1700
Arjan van de Venfa027c22007-02-12 00:55:33 -08001701static const struct file_operations _ctl_fops = {
Arnd Bergmann402ab352010-08-12 04:13:57 +01001702 .open = nonseekable_open,
Alasdair G Kergon27238b22008-02-08 02:09:53 +00001703 .unlocked_ioctl = dm_ctl_ioctl,
Milan Broz76c072b2008-02-08 02:09:56 +00001704 .compat_ioctl = dm_compat_ctl_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001705 .owner = THIS_MODULE,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001706 .llseek = noop_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001707};
1708
1709static struct miscdevice _dm_misc = {
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001710 .minor = MAPPER_CTRL_MINOR,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001711 .name = DM_NAME,
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001712 .nodename = DM_DIR "/" DM_CONTROL_NODE,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001713 .fops = &_ctl_fops
1714};
1715
Peter Rajnoha7e507eb2010-08-12 04:14:05 +01001716MODULE_ALIAS_MISCDEV(MAPPER_CTRL_MINOR);
1717MODULE_ALIAS("devname:" DM_DIR "/" DM_CONTROL_NODE);
1718
Linus Torvalds1da177e2005-04-16 15:20:36 -07001719/*
1720 * Create misc character device and link to DM_DIR/control.
1721 */
1722int __init dm_interface_init(void)
1723{
1724 int r;
1725
1726 r = dm_hash_init();
1727 if (r)
1728 return r;
1729
1730 r = misc_register(&_dm_misc);
1731 if (r) {
1732 DMERR("misc_register failed for control device");
1733 dm_hash_exit();
1734 return r;
1735 }
1736
1737 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
1738 DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
1739 DM_DRIVER_EMAIL);
1740 return 0;
1741}
1742
1743void dm_interface_exit(void)
1744{
1745 if (misc_deregister(&_dm_misc) < 0)
1746 DMERR("misc_deregister failed for control device");
1747
1748 dm_hash_exit();
1749}
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001750
1751/**
1752 * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
1753 * @md: Pointer to mapped_device
1754 * @name: Buffer (size DM_NAME_LEN) for name
1755 * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
1756 */
1757int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
1758{
1759 int r = 0;
1760 struct hash_cell *hc;
1761
1762 if (!md)
1763 return -ENXIO;
1764
Mikulas Patocka60769052009-12-10 23:51:52 +00001765 mutex_lock(&dm_hash_cells_mutex);
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001766 hc = dm_get_mdptr(md);
1767 if (!hc || hc->md != md) {
1768 r = -ENXIO;
1769 goto out;
1770 }
1771
Milan Broz23d39f62009-01-06 03:05:04 +00001772 if (name)
1773 strcpy(name, hc->name);
1774 if (uuid)
1775 strcpy(uuid, hc->uuid ? : "");
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001776
1777out:
Mikulas Patocka60769052009-12-10 23:51:52 +00001778 mutex_unlock(&dm_hash_cells_mutex);
Mike Anderson96a1f7d2007-10-19 22:47:59 +01001779
1780 return r;
1781}