Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. | |
2b06cfff | 3 | * Copyright (C) 2004 - 2006 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
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> | |
1da177e4 | 16 | #include <linux/dm-ioctl.h> |
3ac51e74 | 17 | #include <linux/hdreg.h> |
76c072b4 | 18 | #include <linux/compat.h> |
1da177e4 LT |
19 | |
20 | #include <asm/uaccess.h> | |
21 | ||
72d94861 | 22 | #define DM_MSG_PREFIX "ioctl" |
1da177e4 LT |
23 | #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 | *---------------------------------------------------------------*/ | |
29 | struct 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 | ||
83d5e5b0 MP |
39 | /* |
40 | * A dummy definition to make RCU happy. | |
41 | * struct dm_table should never be dereferenced in this file. | |
42 | */ | |
43 | struct dm_table { | |
44 | int undefined__; | |
45 | }; | |
46 | ||
1da177e4 LT |
47 | struct 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) | |
57 | static struct list_head _name_buckets[NUM_BUCKETS]; | |
58 | static struct list_head _uuid_buckets[NUM_BUCKETS]; | |
59 | ||
2c140a24 | 60 | static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred); |
1da177e4 LT |
61 | |
62 | /* | |
63 | * Guards access to both hash tables. | |
64 | */ | |
65 | static DECLARE_RWSEM(_hash_lock); | |
66 | ||
6076905b MP |
67 | /* |
68 | * Protects use of mdptr to obtain hash cell name and uuid from mapped device. | |
69 | */ | |
70 | static DEFINE_MUTEX(dm_hash_cells_mutex); | |
71 | ||
1da177e4 LT |
72 | static 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 | ||
80 | static int dm_hash_init(void) | |
81 | { | |
82 | init_buckets(_name_buckets); | |
83 | init_buckets(_uuid_buckets); | |
1da177e4 LT |
84 | return 0; |
85 | } | |
86 | ||
87 | static void dm_hash_exit(void) | |
88 | { | |
2c140a24 | 89 | dm_hash_remove_all(false, false, false); |
1da177e4 LT |
90 | } |
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 | *---------------------------------------------------------------*/ | |
97 | static 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 | *---------------------------------------------------------------*/ | |
111 | static 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) | |
7ec75f25 JM |
117 | if (!strcmp(hc->name, str)) { |
118 | dm_get(hc->md); | |
1da177e4 | 119 | return hc; |
7ec75f25 | 120 | } |
1da177e4 LT |
121 | |
122 | return NULL; | |
123 | } | |
124 | ||
125 | static 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) | |
7ec75f25 JM |
131 | if (!strcmp(hc->uuid, str)) { |
132 | dm_get(hc->md); | |
1da177e4 | 133 | return hc; |
7ec75f25 | 134 | } |
1da177e4 LT |
135 | |
136 | return NULL; | |
137 | } | |
138 | ||
ba2e19b0 MP |
139 | static 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 | ||
1da177e4 LT |
157 | /*----------------------------------------------------------------- |
158 | * Inserting, removing and renaming a device. | |
159 | *---------------------------------------------------------------*/ | |
1da177e4 LT |
160 | static 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 | ||
543537bd | 169 | hc->name = kstrdup(name, GFP_KERNEL); |
1da177e4 LT |
170 | if (!hc->name) { |
171 | kfree(hc); | |
172 | return NULL; | |
173 | } | |
174 | ||
175 | if (!uuid) | |
176 | hc->uuid = NULL; | |
177 | ||
178 | else { | |
543537bd | 179 | hc->uuid = kstrdup(uuid, GFP_KERNEL); |
1da177e4 LT |
180 | 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 | ||
194 | static 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 | ||
1da177e4 LT |
203 | /* |
204 | * The kdev_t and uuid of a device can never change once it is | |
205 | * initially inserted. | |
206 | */ | |
207 | static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md) | |
208 | { | |
7ec75f25 | 209 | struct hash_cell *cell, *hc; |
1da177e4 LT |
210 | |
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); | |
7ec75f25 JM |
222 | hc = __get_name_cell(name); |
223 | if (hc) { | |
224 | dm_put(hc->md); | |
1da177e4 | 225 | goto bad; |
7ec75f25 | 226 | } |
1da177e4 LT |
227 | |
228 | list_add(&cell->name_list, _name_buckets + hash_str(name)); | |
229 | ||
230 | if (uuid) { | |
7ec75f25 JM |
231 | hc = __get_uuid_cell(uuid); |
232 | if (hc) { | |
1da177e4 | 233 | list_del(&cell->name_list); |
7ec75f25 | 234 | dm_put(hc->md); |
1da177e4 LT |
235 | goto bad; |
236 | } | |
237 | list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid)); | |
238 | } | |
1da177e4 | 239 | dm_get(md); |
6076905b | 240 | mutex_lock(&dm_hash_cells_mutex); |
1da177e4 | 241 | dm_set_mdptr(md, cell); |
6076905b | 242 | mutex_unlock(&dm_hash_cells_mutex); |
1da177e4 LT |
243 | 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 | ||
83d5e5b0 | 253 | static struct dm_table *__hash_remove(struct hash_cell *hc) |
1da177e4 | 254 | { |
269fd2a6 | 255 | struct dm_table *table; |
83d5e5b0 | 256 | int srcu_idx; |
269fd2a6 | 257 | |
1da177e4 LT |
258 | /* remove from the dev hash */ |
259 | list_del(&hc->uuid_list); | |
260 | list_del(&hc->name_list); | |
6076905b | 261 | mutex_lock(&dm_hash_cells_mutex); |
1da177e4 | 262 | dm_set_mdptr(hc->md, NULL); |
6076905b | 263 | mutex_unlock(&dm_hash_cells_mutex); |
269fd2a6 | 264 | |
83d5e5b0 MP |
265 | table = dm_get_live_table(hc->md, &srcu_idx); |
266 | if (table) | |
269fd2a6 | 267 | dm_table_event(table); |
83d5e5b0 | 268 | dm_put_live_table(hc->md, srcu_idx); |
269fd2a6 | 269 | |
83d5e5b0 | 270 | table = NULL; |
1da177e4 | 271 | if (hc->new_map) |
83d5e5b0 | 272 | table = hc->new_map; |
1134e5ae | 273 | dm_put(hc->md); |
1da177e4 | 274 | free_cell(hc); |
83d5e5b0 MP |
275 | |
276 | return table; | |
1da177e4 LT |
277 | } |
278 | ||
2c140a24 | 279 | static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred) |
1da177e4 | 280 | { |
98f33285 | 281 | int i, dev_skipped; |
1da177e4 | 282 | struct hash_cell *hc; |
98f33285 | 283 | struct mapped_device *md; |
83d5e5b0 | 284 | struct dm_table *t; |
98f33285 KU |
285 | |
286 | retry: | |
287 | dev_skipped = 0; | |
1da177e4 LT |
288 | |
289 | down_write(&_hash_lock); | |
5c6bd75d | 290 | |
1da177e4 | 291 | for (i = 0; i < NUM_BUCKETS; i++) { |
98f33285 KU |
292 | list_for_each_entry(hc, _name_buckets + i, name_list) { |
293 | md = hc->md; | |
294 | dm_get(md); | |
5c6bd75d | 295 | |
2c140a24 MP |
296 | if (keep_open_devices && |
297 | dm_lock_for_deletion(md, mark_deferred, only_deferred)) { | |
98f33285 | 298 | dm_put(md); |
5c6bd75d AK |
299 | dev_skipped++; |
300 | continue; | |
301 | } | |
98f33285 | 302 | |
83d5e5b0 | 303 | t = __hash_remove(hc); |
5c6bd75d | 304 | |
98f33285 | 305 | up_write(&_hash_lock); |
5c6bd75d | 306 | |
83d5e5b0 MP |
307 | if (t) { |
308 | dm_sync_table(md); | |
309 | dm_table_destroy(t); | |
310 | } | |
98f33285 | 311 | dm_put(md); |
3f77316d KU |
312 | if (likely(keep_open_devices)) |
313 | dm_destroy(md); | |
314 | else | |
315 | dm_destroy_immediate(md); | |
98f33285 KU |
316 | |
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; | |
324 | } | |
5c6bd75d AK |
325 | } |
326 | ||
1da177e4 | 327 | up_write(&_hash_lock); |
98f33285 KU |
328 | |
329 | if (dev_skipped) | |
330 | DMWARN("remove_all left %d open device(s)", dev_skipped); | |
1da177e4 LT |
331 | } |
332 | ||
84c89557 PJ |
333 | /* |
334 | * Set the uuid of a hash_cell that isn't already set. | |
335 | */ | |
336 | static 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 | */ | |
349 | static 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 | ||
856a6f1d PR |
368 | static struct mapped_device *dm_hash_rename(struct dm_ioctl *param, |
369 | const char *new) | |
1da177e4 | 370 | { |
84c89557 | 371 | char *new_data, *old_name = NULL; |
1da177e4 | 372 | struct hash_cell *hc; |
81f1777a | 373 | struct dm_table *table; |
856a6f1d | 374 | struct mapped_device *md; |
84c89557 | 375 | unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0; |
83d5e5b0 | 376 | int srcu_idx; |
1da177e4 LT |
377 | |
378 | /* | |
379 | * duplicate new. | |
380 | */ | |
84c89557 PJ |
381 | new_data = kstrdup(new, GFP_KERNEL); |
382 | if (!new_data) | |
856a6f1d | 383 | return ERR_PTR(-ENOMEM); |
1da177e4 LT |
384 | |
385 | down_write(&_hash_lock); | |
386 | ||
387 | /* | |
388 | * Is new free ? | |
389 | */ | |
84c89557 PJ |
390 | if (change_uuid) |
391 | hc = __get_uuid_cell(new); | |
392 | else | |
393 | hc = __get_name_cell(new); | |
394 | ||
1da177e4 | 395 | if (hc) { |
84c89557 PJ |
396 | DMWARN("Unable to change %s on mapped device %s to one that " |
397 | "already exists: %s", | |
398 | change_uuid ? "uuid" : "name", | |
856a6f1d | 399 | param->name, new); |
7ec75f25 | 400 | dm_put(hc->md); |
1da177e4 | 401 | up_write(&_hash_lock); |
84c89557 | 402 | kfree(new_data); |
856a6f1d | 403 | return ERR_PTR(-EBUSY); |
1da177e4 LT |
404 | } |
405 | ||
406 | /* | |
407 | * Is there such a device as 'old' ? | |
408 | */ | |
856a6f1d | 409 | hc = __get_name_cell(param->name); |
1da177e4 | 410 | if (!hc) { |
84c89557 PJ |
411 | DMWARN("Unable to rename non-existent device, %s to %s%s", |
412 | param->name, change_uuid ? "uuid " : "", new); | |
1da177e4 | 413 | up_write(&_hash_lock); |
84c89557 | 414 | kfree(new_data); |
856a6f1d | 415 | return ERR_PTR(-ENXIO); |
1da177e4 LT |
416 | } |
417 | ||
418 | /* | |
84c89557 | 419 | * Does this device already have a uuid? |
1da177e4 | 420 | */ |
84c89557 PJ |
421 | 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); | |
1da177e4 | 435 | |
81f1777a | 436 | /* |
437 | * Wake up any dm event waiters. | |
438 | */ | |
83d5e5b0 MP |
439 | table = dm_get_live_table(hc->md, &srcu_idx); |
440 | if (table) | |
81f1777a | 441 | dm_table_event(table); |
83d5e5b0 | 442 | dm_put_live_table(hc->md, srcu_idx); |
81f1777a | 443 | |
856a6f1d PR |
444 | if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, param->event_nr)) |
445 | param->flags |= DM_UEVENT_GENERATED_FLAG; | |
69267a30 | 446 | |
856a6f1d | 447 | md = hc->md; |
1da177e4 LT |
448 | up_write(&_hash_lock); |
449 | kfree(old_name); | |
856a6f1d PR |
450 | |
451 | return md; | |
1da177e4 LT |
452 | } |
453 | ||
2c140a24 MP |
454 | void dm_deferred_remove(void) |
455 | { | |
456 | dm_hash_remove_all(true, false, true); | |
457 | } | |
458 | ||
1da177e4 LT |
459 | /*----------------------------------------------------------------- |
460 | * Implementation of the ioctl commands | |
461 | *---------------------------------------------------------------*/ | |
462 | /* | |
463 | * All the ioctl commands get dispatched to functions with this | |
464 | * prototype. | |
465 | */ | |
466 | typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size); | |
467 | ||
468 | static int remove_all(struct dm_ioctl *param, size_t param_size) | |
469 | { | |
2c140a24 | 470 | dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false); |
1da177e4 LT |
471 | 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 | |
479 | static 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 | */ | |
488 | static 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 | ||
501 | static 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); | |
f331c029 | 544 | nl->dev = huge_encode_dev(disk_devt(disk)); |
1da177e4 LT |
545 | 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 | ||
558 | static void list_version_get_needed(struct target_type *tt, void *needed_param) | |
559 | { | |
560 | size_t *needed = needed_param; | |
561 | ||
c4cc6635 | 562 | *needed += sizeof(struct dm_target_versions); |
1da177e4 | 563 | *needed += strlen(tt->name); |
1da177e4 LT |
564 | *needed += ALIGN_MASK; |
565 | } | |
566 | ||
567 | static 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 | ||
592 | static 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 | ||
1da177e4 LT |
630 | static 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 | ||
1d0f3ce8 MS |
640 | /* |
641 | * 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 | */ | |
83d5e5b0 | 645 | static struct dm_table *dm_get_inactive_table(struct mapped_device *md, int *srcu_idx) |
1d0f3ce8 MS |
646 | { |
647 | struct hash_cell *hc; | |
648 | struct dm_table *table = NULL; | |
649 | ||
83d5e5b0 MP |
650 | /* increment rcu count, we don't care about the table pointer */ |
651 | dm_get_live_table(md, srcu_idx); | |
652 | ||
1d0f3ce8 MS |
653 | 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; | |
1d0f3ce8 MS |
661 | |
662 | out: | |
663 | up_read(&_hash_lock); | |
664 | ||
665 | return table; | |
666 | } | |
667 | ||
668 | static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md, | |
83d5e5b0 MP |
669 | struct dm_ioctl *param, |
670 | int *srcu_idx) | |
1d0f3ce8 MS |
671 | { |
672 | return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ? | |
83d5e5b0 | 673 | dm_get_inactive_table(md, srcu_idx) : dm_get_live_table(md, srcu_idx); |
1d0f3ce8 MS |
674 | } |
675 | ||
1da177e4 LT |
676 | /* |
677 | * Fills in a dm_ioctl structure, ready for sending back to | |
678 | * userland. | |
679 | */ | |
094ea9a0 | 680 | static void __dev_status(struct mapped_device *md, struct dm_ioctl *param) |
1da177e4 LT |
681 | { |
682 | struct gendisk *disk = dm_disk(md); | |
683 | struct dm_table *table; | |
83d5e5b0 | 684 | int srcu_idx; |
1da177e4 LT |
685 | |
686 | param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG | | |
687 | DM_ACTIVE_PRESENT_FLAG); | |
688 | ||
4f186f8b | 689 | if (dm_suspended_md(md)) |
1da177e4 LT |
690 | param->flags |= DM_SUSPEND_FLAG; |
691 | ||
2c140a24 MP |
692 | if (dm_test_deferred_remove_flag(md)) |
693 | param->flags |= DM_DEFERRED_REMOVE; | |
694 | ||
f331c029 | 695 | param->dev = huge_encode_dev(disk_devt(disk)); |
1da177e4 | 696 | |
5c6bd75d AK |
697 | /* |
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); | |
1da177e4 | 703 | |
1da177e4 | 704 | param->event_nr = dm_get_event_nr(md); |
1d0f3ce8 | 705 | param->target_count = 0; |
1da177e4 | 706 | |
83d5e5b0 | 707 | table = dm_get_live_table(md, &srcu_idx); |
1da177e4 | 708 | if (table) { |
1d0f3ce8 MS |
709 | 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 | } | |
1d0f3ce8 MS |
714 | |
715 | param->flags |= DM_ACTIVE_PRESENT_FLAG; | |
716 | } | |
83d5e5b0 | 717 | dm_put_live_table(md, srcu_idx); |
1d0f3ce8 MS |
718 | |
719 | if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) { | |
83d5e5b0 MP |
720 | int srcu_idx; |
721 | table = dm_get_inactive_table(md, &srcu_idx); | |
1d0f3ce8 MS |
722 | 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); | |
1d0f3ce8 | 726 | } |
83d5e5b0 | 727 | dm_put_live_table(md, srcu_idx); |
1d0f3ce8 | 728 | } |
1da177e4 LT |
729 | } |
730 | ||
731 | static int dev_create(struct dm_ioctl *param, size_t param_size) | |
732 | { | |
2b06cfff | 733 | int r, m = DM_ANY_MINOR; |
1da177e4 LT |
734 | 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) | |
2b06cfff | 741 | m = MINOR(huge_decode_dev(param->dev)); |
1da177e4 | 742 | |
2b06cfff | 743 | r = dm_create(m, &md); |
1da177e4 LT |
744 | if (r) |
745 | return r; | |
746 | ||
747 | r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md); | |
3f77316d KU |
748 | if (r) { |
749 | dm_put(md); | |
750 | dm_destroy(md); | |
751 | return r; | |
752 | } | |
1da177e4 LT |
753 | |
754 | param->flags &= ~DM_INACTIVE_PRESENT_FLAG; | |
755 | ||
094ea9a0 AK |
756 | __dev_status(md, param); |
757 | ||
1da177e4 LT |
758 | dm_put(md); |
759 | ||
3f77316d | 760 | return 0; |
1da177e4 LT |
761 | } |
762 | ||
763 | /* | |
764 | * Always use UUID for lookups if it's present, otherwise use name or dev. | |
765 | */ | |
858119e1 | 766 | static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param) |
1da177e4 | 767 | { |
0ddf9644 | 768 | struct hash_cell *hc = NULL; |
9ade92a9 | 769 | |
0ddf9644 | 770 | if (*param->uuid) { |
759dea20 MP |
771 | if (*param->name || param->dev) |
772 | return NULL; | |
773 | ||
0ddf9644 MP |
774 | hc = __get_uuid_cell(param->uuid); |
775 | if (!hc) | |
776 | return NULL; | |
ba2e19b0 | 777 | } else if (*param->name) { |
759dea20 MP |
778 | if (param->dev) |
779 | return NULL; | |
780 | ||
0ddf9644 MP |
781 | hc = __get_name_cell(param->name); |
782 | if (!hc) | |
783 | return NULL; | |
ba2e19b0 MP |
784 | } else if (param->dev) { |
785 | hc = __get_dev_cell(param->dev); | |
786 | if (!hc) | |
787 | return NULL; | |
788 | } else | |
0ddf9644 | 789 | return NULL; |
9ade92a9 | 790 | |
0ddf9644 MP |
791 | /* |
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; | |
1da177e4 LT |
807 | } |
808 | ||
858119e1 | 809 | static struct mapped_device *find_device(struct dm_ioctl *param) |
1da177e4 LT |
810 | { |
811 | struct hash_cell *hc; | |
812 | struct mapped_device *md = NULL; | |
813 | ||
814 | down_read(&_hash_lock); | |
815 | hc = __find_device_hash_cell(param); | |
0ddf9644 | 816 | if (hc) |
1da177e4 | 817 | md = hc->md; |
1da177e4 LT |
818 | up_read(&_hash_lock); |
819 | ||
820 | return md; | |
821 | } | |
822 | ||
823 | static int dev_remove(struct dm_ioctl *param, size_t param_size) | |
824 | { | |
825 | struct hash_cell *hc; | |
7ec75f25 | 826 | struct mapped_device *md; |
5c6bd75d | 827 | int r; |
83d5e5b0 | 828 | struct dm_table *t; |
1da177e4 LT |
829 | |
830 | down_write(&_hash_lock); | |
831 | hc = __find_device_hash_cell(param); | |
832 | ||
833 | if (!hc) { | |
810b4923 | 834 | DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table."); |
1da177e4 LT |
835 | up_write(&_hash_lock); |
836 | return -ENXIO; | |
837 | } | |
838 | ||
7ec75f25 JM |
839 | md = hc->md; |
840 | ||
5c6bd75d AK |
841 | /* |
842 | * Ensure the device is not open and nothing further can open it. | |
843 | */ | |
2c140a24 | 844 | r = dm_lock_for_deletion(md, !!(param->flags & DM_DEFERRED_REMOVE), false); |
5c6bd75d | 845 | if (r) { |
2c140a24 MP |
846 | if (r == -EBUSY && param->flags & DM_DEFERRED_REMOVE) { |
847 | up_write(&_hash_lock); | |
848 | dm_put(md); | |
849 | return 0; | |
850 | } | |
810b4923 | 851 | DMDEBUG_LIMIT("unable to remove open device %s", hc->name); |
5c6bd75d AK |
852 | up_write(&_hash_lock); |
853 | dm_put(md); | |
854 | return r; | |
855 | } | |
856 | ||
83d5e5b0 | 857 | t = __hash_remove(hc); |
1da177e4 | 858 | up_write(&_hash_lock); |
60935eb2 | 859 | |
83d5e5b0 MP |
860 | if (t) { |
861 | dm_sync_table(md); | |
862 | dm_table_destroy(t); | |
863 | } | |
864 | ||
2c140a24 MP |
865 | param->flags &= ~DM_DEFERRED_REMOVE; |
866 | ||
3abf85b5 PR |
867 | if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr)) |
868 | param->flags |= DM_UEVENT_GENERATED_FLAG; | |
60935eb2 | 869 | |
7ec75f25 | 870 | dm_put(md); |
3f77316d | 871 | dm_destroy(md); |
1da177e4 LT |
872 | return 0; |
873 | } | |
874 | ||
875 | /* | |
876 | * Check a string doesn't overrun the chunk of | |
877 | * memory we copied from userland. | |
878 | */ | |
879 | static 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 | ||
888 | static int dev_rename(struct dm_ioctl *param, size_t param_size) | |
889 | { | |
890 | int r; | |
84c89557 | 891 | char *new_data = (char *) param + param->data_start; |
856a6f1d | 892 | struct mapped_device *md; |
84c89557 | 893 | unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0; |
1da177e4 | 894 | |
84c89557 | 895 | if (new_data < param->data || |
c2b04824 | 896 | invalid_str(new_data, (void *) param + param_size) || !*new_data || |
84c89557 PJ |
897 | strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) { |
898 | DMWARN("Invalid new mapped device name or uuid string supplied."); | |
1da177e4 LT |
899 | return -EINVAL; |
900 | } | |
901 | ||
84c89557 PJ |
902 | if (!change_uuid) { |
903 | r = check_name(new_data); | |
904 | if (r) | |
905 | return r; | |
906 | } | |
1da177e4 | 907 | |
84c89557 | 908 | md = dm_hash_rename(param, new_data); |
856a6f1d PR |
909 | if (IS_ERR(md)) |
910 | return PTR_ERR(md); | |
3abf85b5 | 911 | |
856a6f1d PR |
912 | __dev_status(md, param); |
913 | dm_put(md); | |
914 | ||
915 | return 0; | |
1da177e4 LT |
916 | } |
917 | ||
3ac51e74 DW |
918 | static 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; | |
31998ef1 | 925 | char dummy; |
3ac51e74 DW |
926 | |
927 | md = find_device(param); | |
928 | if (!md) | |
929 | return -ENXIO; | |
930 | ||
27238b2b | 931 | if (geostr < param->data || |
3ac51e74 DW |
932 | invalid_str(geostr, (void *) param + param_size)) { |
933 | DMWARN("Invalid geometry supplied."); | |
934 | goto out; | |
935 | } | |
936 | ||
31998ef1 MP |
937 | x = sscanf(geostr, "%lu %lu %lu %lu%c", indata, |
938 | indata + 1, indata + 2, indata + 3, &dummy); | |
3ac51e74 DW |
939 | |
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); | |
3ac51e74 DW |
957 | |
958 | param->data_size = 0; | |
959 | ||
960 | out: | |
961 | dm_put(md); | |
962 | return r; | |
963 | } | |
964 | ||
1da177e4 LT |
965 | static int do_suspend(struct dm_ioctl *param) |
966 | { | |
967 | int r = 0; | |
a3d77d35 | 968 | unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG; |
1da177e4 LT |
969 | struct mapped_device *md; |
970 | ||
971 | md = find_device(param); | |
972 | if (!md) | |
973 | return -ENXIO; | |
974 | ||
6da487dc | 975 | if (param->flags & DM_SKIP_LOCKFS_FLAG) |
a3d77d35 | 976 | suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG; |
81fdb096 KU |
977 | if (param->flags & DM_NOFLUSH_FLAG) |
978 | suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG; | |
6da487dc | 979 | |
094ea9a0 | 980 | if (!dm_suspended_md(md)) { |
a3d77d35 | 981 | r = dm_suspend(md, suspend_flags); |
094ea9a0 AK |
982 | if (r) |
983 | goto out; | |
984 | } | |
1da177e4 | 985 | |
094ea9a0 | 986 | __dev_status(md, param); |
1da177e4 | 987 | |
094ea9a0 | 988 | out: |
1da177e4 | 989 | dm_put(md); |
094ea9a0 | 990 | |
1da177e4 LT |
991 | return r; |
992 | } | |
993 | ||
994 | static int do_resume(struct dm_ioctl *param) | |
995 | { | |
996 | int r = 0; | |
a3d77d35 | 997 | unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG; |
1da177e4 LT |
998 | struct hash_cell *hc; |
999 | struct mapped_device *md; | |
042d2a9b | 1000 | struct dm_table *new_map, *old_map = NULL; |
1da177e4 LT |
1001 | |
1002 | down_write(&_hash_lock); | |
1003 | ||
1004 | hc = __find_device_hash_cell(param); | |
1005 | if (!hc) { | |
810b4923 | 1006 | DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table."); |
1da177e4 LT |
1007 | up_write(&_hash_lock); |
1008 | return -ENXIO; | |
1009 | } | |
1010 | ||
1011 | md = hc->md; | |
1da177e4 LT |
1012 | |
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 */ | |
6da487dc | 1022 | if (param->flags & DM_SKIP_LOCKFS_FLAG) |
a3d77d35 | 1023 | suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG; |
81fdb096 KU |
1024 | if (param->flags & DM_NOFLUSH_FLAG) |
1025 | suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG; | |
4f186f8b | 1026 | if (!dm_suspended_md(md)) |
a3d77d35 | 1027 | dm_suspend(md, suspend_flags); |
1da177e4 | 1028 | |
042d2a9b AK |
1029 | old_map = dm_swap_table(md, new_map); |
1030 | if (IS_ERR(old_map)) { | |
83d5e5b0 | 1031 | dm_sync_table(md); |
d5816876 | 1032 | dm_table_destroy(new_map); |
1da177e4 | 1033 | dm_put(md); |
042d2a9b | 1034 | return PTR_ERR(old_map); |
1da177e4 LT |
1035 | } |
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); | |
1da177e4 LT |
1041 | } |
1042 | ||
0f3649a9 | 1043 | if (dm_suspended_md(md)) { |
1da177e4 | 1044 | r = dm_resume(md); |
3abf85b5 PR |
1045 | if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr)) |
1046 | param->flags |= DM_UEVENT_GENERATED_FLAG; | |
0f3649a9 | 1047 | } |
1da177e4 | 1048 | |
83d5e5b0 MP |
1049 | /* |
1050 | * Since dm_swap_table synchronizes RCU, nobody should be in | |
1051 | * read-side critical section already. | |
1052 | */ | |
042d2a9b AK |
1053 | if (old_map) |
1054 | dm_table_destroy(old_map); | |
60935eb2 | 1055 | |
0f3649a9 | 1056 | if (!r) |
094ea9a0 | 1057 | __dev_status(md, param); |
1da177e4 LT |
1058 | |
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 | */ | |
1067 | static 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 | */ | |
1079 | static int dev_status(struct dm_ioctl *param, size_t param_size) | |
1080 | { | |
1da177e4 LT |
1081 | struct mapped_device *md; |
1082 | ||
1083 | md = find_device(param); | |
1084 | if (!md) | |
1085 | return -ENXIO; | |
1086 | ||
094ea9a0 | 1087 | __dev_status(md, param); |
1da177e4 | 1088 | dm_put(md); |
094ea9a0 AK |
1089 | |
1090 | return 0; | |
1da177e4 LT |
1091 | } |
1092 | ||
1093 | /* | |
1094 | * Build up the status struct for each target | |
1095 | */ | |
1096 | static 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; | |
1f4e0ff0 | 1104 | unsigned status_flags = 0; |
1da177e4 LT |
1105 | |
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); | |
fd7c092e | 1117 | size_t l; |
1da177e4 LT |
1118 | |
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) { | |
1f4e0ff0 AK |
1142 | if (param->flags & DM_NOFLUSH_FLAG) |
1143 | status_flags |= DM_STATUS_NOFLUSH_FLAG; | |
fd7c092e | 1144 | ti->type->status(ti, type, status_flags, outptr, remaining); |
1da177e4 LT |
1145 | } else |
1146 | outptr[0] = '\0'; | |
1147 | ||
fd7c092e MP |
1148 | l = strlen(outptr) + 1; |
1149 | if (l == remaining) { | |
1150 | param->flags |= DM_BUFFER_FULL_FLAG; | |
1151 | break; | |
1152 | } | |
1153 | ||
1154 | outptr += l; | |
1da177e4 LT |
1155 | 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 | */ | |
1170 | static int dev_wait(struct dm_ioctl *param, size_t param_size) | |
1171 | { | |
094ea9a0 | 1172 | int r = 0; |
1da177e4 LT |
1173 | struct mapped_device *md; |
1174 | struct dm_table *table; | |
83d5e5b0 | 1175 | int srcu_idx; |
1da177e4 LT |
1176 | |
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 | */ | |
094ea9a0 | 1194 | __dev_status(md, param); |
1da177e4 | 1195 | |
83d5e5b0 MP |
1196 | table = dm_get_live_or_inactive_table(md, param, &srcu_idx); |
1197 | if (table) | |
1da177e4 | 1198 | retrieve_status(table, param, param_size); |
83d5e5b0 | 1199 | dm_put_live_table(md, srcu_idx); |
1da177e4 | 1200 | |
094ea9a0 | 1201 | out: |
1da177e4 | 1202 | dm_put(md); |
094ea9a0 | 1203 | |
1da177e4 LT |
1204 | return r; |
1205 | } | |
1206 | ||
aeb5d727 | 1207 | static inline fmode_t get_mode(struct dm_ioctl *param) |
1da177e4 | 1208 | { |
aeb5d727 | 1209 | fmode_t mode = FMODE_READ | FMODE_WRITE; |
1da177e4 LT |
1210 | |
1211 | if (param->flags & DM_READONLY_FLAG) | |
1212 | mode = FMODE_READ; | |
1213 | ||
1214 | return mode; | |
1215 | } | |
1216 | ||
1217 | static 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 | ||
1229 | static 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 | ||
1267 | static int table_load(struct dm_ioctl *param, size_t param_size) | |
1268 | { | |
1269 | int r; | |
1270 | struct hash_cell *hc; | |
83d5e5b0 | 1271 | struct dm_table *t, *old_map = NULL; |
1134e5ae | 1272 | struct mapped_device *md; |
36a0456f | 1273 | struct target_type *immutable_target_type; |
1134e5ae MA |
1274 | |
1275 | md = find_device(param); | |
1276 | if (!md) | |
1277 | return -ENXIO; | |
1da177e4 | 1278 | |
1134e5ae | 1279 | r = dm_table_create(&t, get_mode(param), param->target_count, md); |
1da177e4 | 1280 | if (r) |
f11c1c56 | 1281 | goto err; |
1da177e4 | 1282 | |
00c4fc3b MS |
1283 | /* Protect md->type and md->queue against concurrent table loads. */ |
1284 | dm_lock_md_type(md); | |
1da177e4 | 1285 | r = populate_table(t, param, param_size); |
f11c1c56 MS |
1286 | if (r) |
1287 | goto err_unlock_md_type; | |
1da177e4 | 1288 | |
36a0456f AK |
1289 | 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); | |
36a0456f | 1294 | r = -EINVAL; |
f11c1c56 | 1295 | goto err_unlock_md_type; |
36a0456f AK |
1296 | } |
1297 | ||
a5664dad MS |
1298 | 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."); | |
a5664dad | 1303 | r = -EINVAL; |
f11c1c56 | 1304 | goto err_unlock_md_type; |
a5664dad | 1305 | } |
4a0b4ddf MS |
1306 | |
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."); | |
f11c1c56 | 1311 | goto err_unlock_md_type; |
4a0b4ddf | 1312 | } |
a5664dad MS |
1313 | dm_unlock_md_type(md); |
1314 | ||
1315 | /* stage inactive table */ | |
1da177e4 | 1316 | down_write(&_hash_lock); |
1134e5ae MA |
1317 | hc = dm_get_mdptr(md); |
1318 | if (!hc || hc->md != md) { | |
1319 | DMWARN("device has been removed from the dev hash table."); | |
1134e5ae MA |
1320 | up_write(&_hash_lock); |
1321 | r = -ENXIO; | |
f11c1c56 | 1322 | goto err_destroy_table; |
1da177e4 LT |
1323 | } |
1324 | ||
1325 | if (hc->new_map) | |
83d5e5b0 | 1326 | old_map = hc->new_map; |
1da177e4 | 1327 | hc->new_map = t; |
1134e5ae MA |
1328 | up_write(&_hash_lock); |
1329 | ||
1da177e4 | 1330 | param->flags |= DM_INACTIVE_PRESENT_FLAG; |
094ea9a0 | 1331 | __dev_status(md, param); |
1134e5ae | 1332 | |
83d5e5b0 MP |
1333 | if (old_map) { |
1334 | dm_sync_table(md); | |
1335 | dm_table_destroy(old_map); | |
1336 | } | |
1337 | ||
1134e5ae | 1338 | dm_put(md); |
1da177e4 | 1339 | |
f11c1c56 MS |
1340 | return 0; |
1341 | ||
1342 | err_unlock_md_type: | |
1343 | dm_unlock_md_type(md); | |
1344 | err_destroy_table: | |
1345 | dm_table_destroy(t); | |
1346 | err: | |
1347 | dm_put(md); | |
1348 | ||
1da177e4 LT |
1349 | return r; |
1350 | } | |
1351 | ||
1352 | static int table_clear(struct dm_ioctl *param, size_t param_size) | |
1353 | { | |
1da177e4 | 1354 | struct hash_cell *hc; |
7ec75f25 | 1355 | struct mapped_device *md; |
83d5e5b0 | 1356 | struct dm_table *old_map = NULL; |
1da177e4 LT |
1357 | |
1358 | down_write(&_hash_lock); | |
1359 | ||
1360 | hc = __find_device_hash_cell(param); | |
1361 | if (!hc) { | |
810b4923 | 1362 | DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table."); |
1da177e4 LT |
1363 | up_write(&_hash_lock); |
1364 | return -ENXIO; | |
1365 | } | |
1366 | ||
1367 | if (hc->new_map) { | |
83d5e5b0 | 1368 | old_map = hc->new_map; |
1da177e4 LT |
1369 | hc->new_map = NULL; |
1370 | } | |
1371 | ||
1372 | param->flags &= ~DM_INACTIVE_PRESENT_FLAG; | |
1373 | ||
094ea9a0 | 1374 | __dev_status(hc->md, param); |
7ec75f25 | 1375 | md = hc->md; |
1da177e4 | 1376 | up_write(&_hash_lock); |
83d5e5b0 MP |
1377 | if (old_map) { |
1378 | dm_sync_table(md); | |
1379 | dm_table_destroy(old_map); | |
1380 | } | |
7ec75f25 | 1381 | dm_put(md); |
094ea9a0 AK |
1382 | |
1383 | return 0; | |
1da177e4 LT |
1384 | } |
1385 | ||
1386 | /* | |
1387 | * Retrieves a list of devices used by a particular dm device. | |
1388 | */ | |
1389 | static 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; | |
82b1519b | 1395 | struct dm_dev_internal *dd; |
1da177e4 LT |
1396 | 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) | |
82b1519b | 1421 | deps->dev[count++] = huge_encode_dev(dd->dm_dev.bdev->bd_dev); |
1da177e4 LT |
1422 | |
1423 | param->data_size = param->data_start + needed; | |
1424 | } | |
1425 | ||
1426 | static int table_deps(struct dm_ioctl *param, size_t param_size) | |
1427 | { | |
1da177e4 LT |
1428 | struct mapped_device *md; |
1429 | struct dm_table *table; | |
83d5e5b0 | 1430 | int srcu_idx; |
1da177e4 LT |
1431 | |
1432 | md = find_device(param); | |
1433 | if (!md) | |
1434 | return -ENXIO; | |
1435 | ||
094ea9a0 | 1436 | __dev_status(md, param); |
1da177e4 | 1437 | |
83d5e5b0 MP |
1438 | table = dm_get_live_or_inactive_table(md, param, &srcu_idx); |
1439 | if (table) | |
1da177e4 | 1440 | retrieve_deps(table, param, param_size); |
83d5e5b0 | 1441 | dm_put_live_table(md, srcu_idx); |
1da177e4 | 1442 | |
1da177e4 | 1443 | dm_put(md); |
094ea9a0 AK |
1444 | |
1445 | return 0; | |
1da177e4 LT |
1446 | } |
1447 | ||
1448 | /* | |
1449 | * Return the status of a device as a text string for each | |
1450 | * target. | |
1451 | */ | |
1452 | static int table_status(struct dm_ioctl *param, size_t param_size) | |
1453 | { | |
1da177e4 LT |
1454 | struct mapped_device *md; |
1455 | struct dm_table *table; | |
83d5e5b0 | 1456 | int srcu_idx; |
1da177e4 LT |
1457 | |
1458 | md = find_device(param); | |
1459 | if (!md) | |
1460 | return -ENXIO; | |
1461 | ||
094ea9a0 | 1462 | __dev_status(md, param); |
1da177e4 | 1463 | |
83d5e5b0 MP |
1464 | table = dm_get_live_or_inactive_table(md, param, &srcu_idx); |
1465 | if (table) | |
1da177e4 | 1466 | retrieve_status(table, param, param_size); |
83d5e5b0 | 1467 | dm_put_live_table(md, srcu_idx); |
1da177e4 | 1468 | |
1da177e4 | 1469 | dm_put(md); |
094ea9a0 AK |
1470 | |
1471 | return 0; | |
1da177e4 LT |
1472 | } |
1473 | ||
a2606241 | 1474 | /* |
fd2ed4d2 MP |
1475 | * Process device-mapper dependent messages. Messages prefixed with '@' |
1476 | * are processed by the DM core. All others are delivered to the target. | |
a2606241 MP |
1477 | * Returns a number <= 1 if message was processed by device mapper. |
1478 | * Returns 2 if message should be delivered to the target. | |
1479 | */ | |
1480 | static int message_for_md(struct mapped_device *md, unsigned argc, char **argv, | |
1481 | char *result, unsigned maxlen) | |
1482 | { | |
fd2ed4d2 MP |
1483 | int r; |
1484 | ||
1485 | if (**argv != '@') | |
1486 | return 2; /* no '@' prefix, deliver to target */ | |
1487 | ||
2c140a24 MP |
1488 | 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 | ||
fd2ed4d2 MP |
1496 | 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; | |
a2606241 MP |
1502 | } |
1503 | ||
1da177e4 LT |
1504 | /* |
1505 | * Pass a message to the target that's at the supplied device offset. | |
1506 | */ | |
1507 | static 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; | |
a2606241 MP |
1515 | size_t maxlen; |
1516 | char *result = get_result_buffer(param, param_size, &maxlen); | |
83d5e5b0 | 1517 | int srcu_idx; |
1da177e4 LT |
1518 | |
1519 | md = find_device(param); | |
1520 | if (!md) | |
1521 | return -ENXIO; | |
1522 | ||
027d50f9 | 1523 | if (tmsg < (struct dm_target_msg *) param->data || |
1da177e4 LT |
1524 | 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 | ||
2ca4c92f AK |
1536 | if (!argc) { |
1537 | DMWARN("Empty message received."); | |
902c6a96 | 1538 | goto out_argv; |
2ca4c92f AK |
1539 | } |
1540 | ||
a2606241 MP |
1541 | r = message_for_md(md, argc, argv, result, maxlen); |
1542 | if (r <= 1) | |
1543 | goto out_argv; | |
1544 | ||
83d5e5b0 | 1545 | table = dm_get_live_table(md, &srcu_idx); |
1da177e4 | 1546 | if (!table) |
83d5e5b0 | 1547 | goto out_table; |
1da177e4 | 1548 | |
c50abeb3 MA |
1549 | if (dm_deleting_md(md)) { |
1550 | r = -ENXIO; | |
1551 | goto out_table; | |
1552 | } | |
1553 | ||
512875bd JN |
1554 | ti = dm_table_find_target(table, tmsg->sector); |
1555 | if (!dm_target_is_valid(ti)) { | |
1da177e4 LT |
1556 | DMWARN("Target message sector outside device."); |
1557 | r = -EINVAL; | |
512875bd | 1558 | } else if (ti->type->message) |
1da177e4 LT |
1559 | r = ti->type->message(ti, argc, argv); |
1560 | else { | |
1561 | DMWARN("Target type does not support messages"); | |
1562 | r = -EINVAL; | |
1563 | } | |
1564 | ||
c50abeb3 | 1565 | out_table: |
83d5e5b0 | 1566 | dm_put_live_table(md, srcu_idx); |
1da177e4 LT |
1567 | out_argv: |
1568 | kfree(argv); | |
1569 | out: | |
a2606241 MP |
1570 | if (r >= 0) |
1571 | __dev_status(md, param); | |
1572 | ||
1573 | if (r == 1) { | |
1574 | param->flags |= DM_DATA_OUT_FLAG; | |
fd2ed4d2 | 1575 | if (dm_message_test_buffer_overflow(result, maxlen)) |
a2606241 MP |
1576 | param->flags |= DM_BUFFER_FULL_FLAG; |
1577 | else | |
1578 | param->data_size = param->data_start + strlen(result) + 1; | |
1579 | r = 0; | |
1580 | } | |
1581 | ||
1da177e4 LT |
1582 | dm_put(md); |
1583 | return r; | |
1584 | } | |
1585 | ||
e2914cc2 MP |
1586 | /* |
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 | ||
1da177e4 LT |
1594 | /*----------------------------------------------------------------- |
1595 | * Implementation of open/close/ioctl on the special char | |
1596 | * device. | |
1597 | *---------------------------------------------------------------*/ | |
e2914cc2 | 1598 | static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags) |
1da177e4 LT |
1599 | { |
1600 | static struct { | |
1601 | int cmd; | |
e2914cc2 | 1602 | int flags; |
1da177e4 LT |
1603 | ioctl_fn fn; |
1604 | } _ioctls[] = { | |
e2914cc2 MP |
1605 | {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}, | |
1608 | ||
1609 | {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}, | |
1615 | ||
1616 | {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}, | |
1620 | ||
1621 | {DM_LIST_VERSIONS_CMD, 0, list_versions}, | |
1622 | ||
1623 | {DM_TARGET_MSG_CMD, 0, target_message}, | |
1624 | {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry} | |
1da177e4 LT |
1625 | }; |
1626 | ||
e2914cc2 MP |
1627 | if (unlikely(cmd >= ARRAY_SIZE(_ioctls))) |
1628 | return NULL; | |
1629 | ||
1630 | *ioctl_flags = _ioctls[cmd].flags; | |
1631 | return _ioctls[cmd].fn; | |
1da177e4 LT |
1632 | } |
1633 | ||
1634 | /* | |
1635 | * As well as checking the version compatibility this always | |
1636 | * copies the kernel interface version out. | |
1637 | */ | |
1638 | static 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 | ||
02cde50b MP |
1668 | #define DM_PARAMS_KMALLOC 0x0001 /* Params alloced with kmalloc */ |
1669 | #define DM_PARAMS_VMALLOC 0x0002 /* Params alloced with vmalloc */ | |
9c5091f2 MP |
1670 | #define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */ |
1671 | ||
1672 | static 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 | ||
02cde50b MP |
1677 | if (param_flags & DM_PARAMS_KMALLOC) |
1678 | kfree(param); | |
9c5091f2 MP |
1679 | if (param_flags & DM_PARAMS_VMALLOC) |
1680 | vfree(param); | |
9c5091f2 MP |
1681 | } |
1682 | ||
02cde50b MP |
1683 | static 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) | |
1da177e4 | 1686 | { |
02cde50b | 1687 | struct dm_ioctl *dmi; |
f8681205 | 1688 | int secure_data; |
02cde50b | 1689 | const size_t minimum_data_size = sizeof(*param_kernel) - sizeof(param_kernel->data); |
1da177e4 | 1690 | |
02cde50b | 1691 | if (copy_from_user(param_kernel, user, minimum_data_size)) |
1da177e4 LT |
1692 | return -EFAULT; |
1693 | ||
02cde50b | 1694 | if (param_kernel->data_size < minimum_data_size) |
1da177e4 LT |
1695 | return -EINVAL; |
1696 | ||
02cde50b | 1697 | secure_data = param_kernel->flags & DM_SECURE_DATA_FLAG; |
f8681205 | 1698 | |
9c5091f2 MP |
1699 | *param_flags = secure_data ? DM_WIPE_BUFFER : 0; |
1700 | ||
02cde50b MP |
1701 | if (ioctl_flags & IOCTL_FLAGS_NO_PARAMS) { |
1702 | dmi = param_kernel; | |
1703 | dmi->data_size = minimum_data_size; | |
1704 | goto data_copied; | |
1705 | } | |
1706 | ||
5023e5cf MP |
1707 | /* |
1708 | * Try to avoid low memory issues when a device is suspended. | |
9c5091f2 | 1709 | * Use kmalloc() rather than vmalloc() when we can. |
5023e5cf | 1710 | */ |
9c5091f2 | 1711 | dmi = NULL; |
02cde50b MP |
1712 | 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; | |
1716 | } | |
9c5091f2 MP |
1717 | |
1718 | if (!dmi) { | |
1c0e883e MP |
1719 | unsigned noio_flag; |
1720 | noio_flag = memalloc_noio_save(); | |
220cd058 | 1721 | dmi = __vmalloc(param_kernel->data_size, GFP_NOIO | __GFP_REPEAT | __GFP_HIGH | __GFP_HIGHMEM, PAGE_KERNEL); |
1c0e883e | 1722 | memalloc_noio_restore(noio_flag); |
02cde50b MP |
1723 | if (dmi) |
1724 | *param_flags |= DM_PARAMS_VMALLOC; | |
9c5091f2 MP |
1725 | } |
1726 | ||
f8681205 | 1727 | if (!dmi) { |
02cde50b | 1728 | if (secure_data && clear_user(user, param_kernel->data_size)) |
f8681205 | 1729 | return -EFAULT; |
1da177e4 | 1730 | return -ENOMEM; |
f8681205 | 1731 | } |
1da177e4 | 1732 | |
02cde50b | 1733 | if (copy_from_user(dmi, user, param_kernel->data_size)) |
6bb43b5d | 1734 | goto bad; |
1da177e4 | 1735 | |
02cde50b | 1736 | data_copied: |
e910d7eb AK |
1737 | /* |
1738 | * Abort if something changed the ioctl data while it was being copied. | |
1739 | */ | |
02cde50b | 1740 | if (dmi->data_size != param_kernel->data_size) { |
e910d7eb AK |
1741 | DMERR("rejecting ioctl: data size modified while processing parameters"); |
1742 | goto bad; | |
1743 | } | |
1744 | ||
f8681205 | 1745 | /* Wipe the user buffer so we do not return it to userspace */ |
02cde50b | 1746 | if (secure_data && clear_user(user, param_kernel->data_size)) |
f8681205 MB |
1747 | goto bad; |
1748 | ||
1da177e4 LT |
1749 | *param = dmi; |
1750 | return 0; | |
6bb43b5d MB |
1751 | |
1752 | bad: | |
02cde50b | 1753 | free_params(dmi, param_kernel->data_size, *param_flags); |
9c5091f2 | 1754 | |
6bb43b5d | 1755 | return -EFAULT; |
1da177e4 LT |
1756 | } |
1757 | ||
1758 | static int validate_params(uint cmd, struct dm_ioctl *param) | |
1759 | { | |
1760 | /* Always clear this flag */ | |
1761 | param->flags &= ~DM_BUFFER_FULL_FLAG; | |
3abf85b5 | 1762 | param->flags &= ~DM_UEVENT_GENERATED_FLAG; |
f8681205 | 1763 | param->flags &= ~DM_SECURE_DATA_FLAG; |
a2606241 | 1764 | param->flags &= ~DM_DATA_OUT_FLAG; |
1da177e4 LT |
1765 | |
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 | ||
27238b2b | 1789 | static int ctl_ioctl(uint command, struct dm_ioctl __user *user) |
1da177e4 LT |
1790 | { |
1791 | int r = 0; | |
e2914cc2 | 1792 | int ioctl_flags; |
9c5091f2 | 1793 | int param_flags; |
1da177e4 | 1794 | unsigned int cmd; |
a26ffd4a | 1795 | struct dm_ioctl *uninitialized_var(param); |
1da177e4 | 1796 | ioctl_fn fn = NULL; |
6bb43b5d | 1797 | size_t input_param_size; |
02cde50b | 1798 | struct dm_ioctl param_kernel; |
1da177e4 LT |
1799 | |
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 | ||
e2914cc2 | 1823 | fn = lookup_ioctl(cmd, &ioctl_flags); |
1da177e4 LT |
1824 | if (!fn) { |
1825 | DMWARN("dm_ctl_ioctl: unknown command 0x%x", command); | |
1826 | return -ENOTTY; | |
1827 | } | |
1828 | ||
1da177e4 LT |
1829 | /* |
1830 | * Copy the parameters into kernel space. | |
1831 | */ | |
02cde50b | 1832 | r = copy_params(user, ¶m_kernel, ioctl_flags, ¶m, ¶m_flags); |
1da177e4 | 1833 | |
dab6a429 AK |
1834 | if (r) |
1835 | return r; | |
1da177e4 | 1836 | |
f8681205 | 1837 | input_param_size = param->data_size; |
1da177e4 LT |
1838 | r = validate_params(cmd, param); |
1839 | if (r) | |
1840 | goto out; | |
1841 | ||
1da177e4 | 1842 | param->data_size = sizeof(*param); |
6bb43b5d | 1843 | r = fn(param, input_param_size); |
1da177e4 | 1844 | |
e2914cc2 MP |
1845 | 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 | ||
1da177e4 LT |
1849 | /* |
1850 | * Copy the results back to userland. | |
1851 | */ | |
1852 | if (!r && copy_to_user(user, param, param->data_size)) | |
1853 | r = -EFAULT; | |
1854 | ||
6bb43b5d | 1855 | out: |
9c5091f2 | 1856 | free_params(param, input_param_size, param_flags); |
1da177e4 LT |
1857 | return r; |
1858 | } | |
1859 | ||
27238b2b AK |
1860 | static 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 | ||
76c072b4 MB |
1865 | #ifdef CONFIG_COMPAT |
1866 | static 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 | ||
fa027c2a | 1874 | static const struct file_operations _ctl_fops = { |
402ab352 | 1875 | .open = nonseekable_open, |
27238b2b | 1876 | .unlocked_ioctl = dm_ctl_ioctl, |
76c072b4 | 1877 | .compat_ioctl = dm_compat_ctl_ioctl, |
1da177e4 | 1878 | .owner = THIS_MODULE, |
6038f373 | 1879 | .llseek = noop_llseek, |
1da177e4 LT |
1880 | }; |
1881 | ||
1882 | static struct miscdevice _dm_misc = { | |
7e507eb6 | 1883 | .minor = MAPPER_CTRL_MINOR, |
1da177e4 | 1884 | .name = DM_NAME, |
7e507eb6 | 1885 | .nodename = DM_DIR "/" DM_CONTROL_NODE, |
1da177e4 LT |
1886 | .fops = &_ctl_fops |
1887 | }; | |
1888 | ||
7e507eb6 PR |
1889 | MODULE_ALIAS_MISCDEV(MAPPER_CTRL_MINOR); |
1890 | MODULE_ALIAS("devname:" DM_DIR "/" DM_CONTROL_NODE); | |
1891 | ||
1da177e4 LT |
1892 | /* |
1893 | * Create misc character device and link to DM_DIR/control. | |
1894 | */ | |
1895 | int __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 | ||
1916 | void 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 | } | |
96a1f7db MA |
1923 | |
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 | */ | |
1930 | int 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 | ||
6076905b | 1938 | mutex_lock(&dm_hash_cells_mutex); |
96a1f7db MA |
1939 | hc = dm_get_mdptr(md); |
1940 | if (!hc || hc->md != md) { | |
1941 | r = -ENXIO; | |
1942 | goto out; | |
1943 | } | |
1944 | ||
23d39f63 MB |
1945 | if (name) |
1946 | strcpy(name, hc->name); | |
1947 | if (uuid) | |
1948 | strcpy(uuid, hc->uuid ? : ""); | |
96a1f7db MA |
1949 | |
1950 | out: | |
6076905b | 1951 | mutex_unlock(&dm_hash_cells_mutex); |
96a1f7db MA |
1952 | |
1953 | return r; | |
1954 | } |