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Commit | Line | Data |
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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> | |
16 | #include <linux/devfs_fs_kernel.h> | |
17 | #include <linux/dm-ioctl.h> | |
3ac51e74 | 18 | #include <linux/hdreg.h> |
1da177e4 LT |
19 | |
20 | #include <asm/uaccess.h> | |
21 | ||
22 | #define DM_DRIVER_EMAIL "dm-devel@redhat.com" | |
23 | ||
24 | /*----------------------------------------------------------------- | |
25 | * The ioctl interface needs to be able to look up devices by | |
26 | * name or uuid. | |
27 | *---------------------------------------------------------------*/ | |
28 | struct hash_cell { | |
29 | struct list_head name_list; | |
30 | struct list_head uuid_list; | |
31 | ||
32 | char *name; | |
33 | char *uuid; | |
34 | struct mapped_device *md; | |
35 | struct dm_table *new_map; | |
36 | }; | |
37 | ||
38 | struct vers_iter { | |
39 | size_t param_size; | |
40 | struct dm_target_versions *vers, *old_vers; | |
41 | char *end; | |
42 | uint32_t flags; | |
43 | }; | |
44 | ||
45 | ||
46 | #define NUM_BUCKETS 64 | |
47 | #define MASK_BUCKETS (NUM_BUCKETS - 1) | |
48 | static struct list_head _name_buckets[NUM_BUCKETS]; | |
49 | static struct list_head _uuid_buckets[NUM_BUCKETS]; | |
50 | ||
5c6bd75d | 51 | static void dm_hash_remove_all(int keep_open_devices); |
1da177e4 LT |
52 | |
53 | /* | |
54 | * Guards access to both hash tables. | |
55 | */ | |
56 | static DECLARE_RWSEM(_hash_lock); | |
57 | ||
58 | static void init_buckets(struct list_head *buckets) | |
59 | { | |
60 | unsigned int i; | |
61 | ||
62 | for (i = 0; i < NUM_BUCKETS; i++) | |
63 | INIT_LIST_HEAD(buckets + i); | |
64 | } | |
65 | ||
66 | static int dm_hash_init(void) | |
67 | { | |
68 | init_buckets(_name_buckets); | |
69 | init_buckets(_uuid_buckets); | |
70 | devfs_mk_dir(DM_DIR); | |
71 | return 0; | |
72 | } | |
73 | ||
74 | static void dm_hash_exit(void) | |
75 | { | |
5c6bd75d | 76 | dm_hash_remove_all(0); |
1da177e4 LT |
77 | devfs_remove(DM_DIR); |
78 | } | |
79 | ||
80 | /*----------------------------------------------------------------- | |
81 | * Hash function: | |
82 | * We're not really concerned with the str hash function being | |
83 | * fast since it's only used by the ioctl interface. | |
84 | *---------------------------------------------------------------*/ | |
85 | static unsigned int hash_str(const char *str) | |
86 | { | |
87 | const unsigned int hash_mult = 2654435387U; | |
88 | unsigned int h = 0; | |
89 | ||
90 | while (*str) | |
91 | h = (h + (unsigned int) *str++) * hash_mult; | |
92 | ||
93 | return h & MASK_BUCKETS; | |
94 | } | |
95 | ||
96 | /*----------------------------------------------------------------- | |
97 | * Code for looking up a device by name | |
98 | *---------------------------------------------------------------*/ | |
99 | static struct hash_cell *__get_name_cell(const char *str) | |
100 | { | |
101 | struct hash_cell *hc; | |
102 | unsigned int h = hash_str(str); | |
103 | ||
104 | list_for_each_entry (hc, _name_buckets + h, name_list) | |
7ec75f25 JM |
105 | if (!strcmp(hc->name, str)) { |
106 | dm_get(hc->md); | |
1da177e4 | 107 | return hc; |
7ec75f25 | 108 | } |
1da177e4 LT |
109 | |
110 | return NULL; | |
111 | } | |
112 | ||
113 | static struct hash_cell *__get_uuid_cell(const char *str) | |
114 | { | |
115 | struct hash_cell *hc; | |
116 | unsigned int h = hash_str(str); | |
117 | ||
118 | list_for_each_entry (hc, _uuid_buckets + h, uuid_list) | |
7ec75f25 JM |
119 | if (!strcmp(hc->uuid, str)) { |
120 | dm_get(hc->md); | |
1da177e4 | 121 | return hc; |
7ec75f25 | 122 | } |
1da177e4 LT |
123 | |
124 | return NULL; | |
125 | } | |
126 | ||
127 | /*----------------------------------------------------------------- | |
128 | * Inserting, removing and renaming a device. | |
129 | *---------------------------------------------------------------*/ | |
1da177e4 LT |
130 | static struct hash_cell *alloc_cell(const char *name, const char *uuid, |
131 | struct mapped_device *md) | |
132 | { | |
133 | struct hash_cell *hc; | |
134 | ||
135 | hc = kmalloc(sizeof(*hc), GFP_KERNEL); | |
136 | if (!hc) | |
137 | return NULL; | |
138 | ||
543537bd | 139 | hc->name = kstrdup(name, GFP_KERNEL); |
1da177e4 LT |
140 | if (!hc->name) { |
141 | kfree(hc); | |
142 | return NULL; | |
143 | } | |
144 | ||
145 | if (!uuid) | |
146 | hc->uuid = NULL; | |
147 | ||
148 | else { | |
543537bd | 149 | hc->uuid = kstrdup(uuid, GFP_KERNEL); |
1da177e4 LT |
150 | if (!hc->uuid) { |
151 | kfree(hc->name); | |
152 | kfree(hc); | |
153 | return NULL; | |
154 | } | |
155 | } | |
156 | ||
157 | INIT_LIST_HEAD(&hc->name_list); | |
158 | INIT_LIST_HEAD(&hc->uuid_list); | |
159 | hc->md = md; | |
160 | hc->new_map = NULL; | |
161 | return hc; | |
162 | } | |
163 | ||
164 | static void free_cell(struct hash_cell *hc) | |
165 | { | |
166 | if (hc) { | |
167 | kfree(hc->name); | |
168 | kfree(hc->uuid); | |
169 | kfree(hc); | |
170 | } | |
171 | } | |
172 | ||
173 | /* | |
174 | * devfs stuff. | |
175 | */ | |
176 | static int register_with_devfs(struct hash_cell *hc) | |
177 | { | |
178 | struct gendisk *disk = dm_disk(hc->md); | |
179 | ||
180 | devfs_mk_bdev(MKDEV(disk->major, disk->first_minor), | |
181 | S_IFBLK | S_IRUSR | S_IWUSR | S_IRGRP, | |
182 | DM_DIR "/%s", hc->name); | |
183 | return 0; | |
184 | } | |
185 | ||
186 | static int unregister_with_devfs(struct hash_cell *hc) | |
187 | { | |
188 | devfs_remove(DM_DIR"/%s", hc->name); | |
189 | return 0; | |
190 | } | |
191 | ||
192 | /* | |
193 | * The kdev_t and uuid of a device can never change once it is | |
194 | * initially inserted. | |
195 | */ | |
196 | static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md) | |
197 | { | |
7ec75f25 | 198 | struct hash_cell *cell, *hc; |
1da177e4 LT |
199 | |
200 | /* | |
201 | * Allocate the new cells. | |
202 | */ | |
203 | cell = alloc_cell(name, uuid, md); | |
204 | if (!cell) | |
205 | return -ENOMEM; | |
206 | ||
207 | /* | |
208 | * Insert the cell into both hash tables. | |
209 | */ | |
210 | down_write(&_hash_lock); | |
7ec75f25 JM |
211 | hc = __get_name_cell(name); |
212 | if (hc) { | |
213 | dm_put(hc->md); | |
1da177e4 | 214 | goto bad; |
7ec75f25 | 215 | } |
1da177e4 LT |
216 | |
217 | list_add(&cell->name_list, _name_buckets + hash_str(name)); | |
218 | ||
219 | if (uuid) { | |
7ec75f25 JM |
220 | hc = __get_uuid_cell(uuid); |
221 | if (hc) { | |
1da177e4 | 222 | list_del(&cell->name_list); |
7ec75f25 | 223 | dm_put(hc->md); |
1da177e4 LT |
224 | goto bad; |
225 | } | |
226 | list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid)); | |
227 | } | |
228 | register_with_devfs(cell); | |
229 | dm_get(md); | |
230 | dm_set_mdptr(md, cell); | |
231 | up_write(&_hash_lock); | |
232 | ||
233 | return 0; | |
234 | ||
235 | bad: | |
236 | up_write(&_hash_lock); | |
237 | free_cell(cell); | |
238 | return -EBUSY; | |
239 | } | |
240 | ||
241 | static void __hash_remove(struct hash_cell *hc) | |
242 | { | |
269fd2a6 | 243 | struct dm_table *table; |
244 | ||
1da177e4 LT |
245 | /* remove from the dev hash */ |
246 | list_del(&hc->uuid_list); | |
247 | list_del(&hc->name_list); | |
248 | unregister_with_devfs(hc); | |
249 | dm_set_mdptr(hc->md, NULL); | |
269fd2a6 | 250 | |
251 | table = dm_get_table(hc->md); | |
252 | if (table) { | |
253 | dm_table_event(table); | |
254 | dm_table_put(table); | |
255 | } | |
256 | ||
1da177e4 LT |
257 | if (hc->new_map) |
258 | dm_table_put(hc->new_map); | |
1134e5ae | 259 | dm_put(hc->md); |
1da177e4 LT |
260 | free_cell(hc); |
261 | } | |
262 | ||
5c6bd75d | 263 | static void dm_hash_remove_all(int keep_open_devices) |
1da177e4 | 264 | { |
5c6bd75d | 265 | int i, dev_skipped, dev_removed; |
1da177e4 LT |
266 | struct hash_cell *hc; |
267 | struct list_head *tmp, *n; | |
268 | ||
269 | down_write(&_hash_lock); | |
5c6bd75d AK |
270 | |
271 | retry: | |
272 | dev_skipped = dev_removed = 0; | |
1da177e4 LT |
273 | for (i = 0; i < NUM_BUCKETS; i++) { |
274 | list_for_each_safe (tmp, n, _name_buckets + i) { | |
275 | hc = list_entry(tmp, struct hash_cell, name_list); | |
5c6bd75d AK |
276 | |
277 | if (keep_open_devices && | |
278 | dm_lock_for_deletion(hc->md)) { | |
279 | dev_skipped++; | |
280 | continue; | |
281 | } | |
1da177e4 | 282 | __hash_remove(hc); |
5c6bd75d | 283 | dev_removed = 1; |
1da177e4 LT |
284 | } |
285 | } | |
5c6bd75d AK |
286 | |
287 | /* | |
288 | * Some mapped devices may be using other mapped devices, so if any | |
289 | * still exist, repeat until we make no further progress. | |
290 | */ | |
291 | if (dev_skipped) { | |
292 | if (dev_removed) | |
293 | goto retry; | |
294 | ||
295 | DMWARN("remove_all left %d open device(s)", dev_skipped); | |
296 | } | |
297 | ||
1da177e4 LT |
298 | up_write(&_hash_lock); |
299 | } | |
300 | ||
301 | static int dm_hash_rename(const char *old, const char *new) | |
302 | { | |
303 | char *new_name, *old_name; | |
304 | struct hash_cell *hc; | |
81f1777a | 305 | struct dm_table *table; |
1da177e4 LT |
306 | |
307 | /* | |
308 | * duplicate new. | |
309 | */ | |
543537bd | 310 | new_name = kstrdup(new, GFP_KERNEL); |
1da177e4 LT |
311 | if (!new_name) |
312 | return -ENOMEM; | |
313 | ||
314 | down_write(&_hash_lock); | |
315 | ||
316 | /* | |
317 | * Is new free ? | |
318 | */ | |
319 | hc = __get_name_cell(new); | |
320 | if (hc) { | |
321 | DMWARN("asked to rename to an already existing name %s -> %s", | |
322 | old, new); | |
7ec75f25 | 323 | dm_put(hc->md); |
1da177e4 LT |
324 | up_write(&_hash_lock); |
325 | kfree(new_name); | |
326 | return -EBUSY; | |
327 | } | |
328 | ||
329 | /* | |
330 | * Is there such a device as 'old' ? | |
331 | */ | |
332 | hc = __get_name_cell(old); | |
333 | if (!hc) { | |
334 | DMWARN("asked to rename a non existent device %s -> %s", | |
335 | old, new); | |
336 | up_write(&_hash_lock); | |
337 | kfree(new_name); | |
338 | return -ENXIO; | |
339 | } | |
340 | ||
341 | /* | |
342 | * rename and move the name cell. | |
343 | */ | |
344 | unregister_with_devfs(hc); | |
345 | ||
346 | list_del(&hc->name_list); | |
347 | old_name = hc->name; | |
348 | hc->name = new_name; | |
349 | list_add(&hc->name_list, _name_buckets + hash_str(new_name)); | |
350 | ||
351 | /* rename the device node in devfs */ | |
352 | register_with_devfs(hc); | |
353 | ||
81f1777a | 354 | /* |
355 | * Wake up any dm event waiters. | |
356 | */ | |
357 | table = dm_get_table(hc->md); | |
358 | if (table) { | |
359 | dm_table_event(table); | |
360 | dm_table_put(table); | |
361 | } | |
362 | ||
7ec75f25 | 363 | dm_put(hc->md); |
1da177e4 LT |
364 | up_write(&_hash_lock); |
365 | kfree(old_name); | |
366 | return 0; | |
367 | } | |
368 | ||
369 | /*----------------------------------------------------------------- | |
370 | * Implementation of the ioctl commands | |
371 | *---------------------------------------------------------------*/ | |
372 | /* | |
373 | * All the ioctl commands get dispatched to functions with this | |
374 | * prototype. | |
375 | */ | |
376 | typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size); | |
377 | ||
378 | static int remove_all(struct dm_ioctl *param, size_t param_size) | |
379 | { | |
5c6bd75d | 380 | dm_hash_remove_all(1); |
1da177e4 LT |
381 | param->data_size = 0; |
382 | return 0; | |
383 | } | |
384 | ||
385 | /* | |
386 | * Round up the ptr to an 8-byte boundary. | |
387 | */ | |
388 | #define ALIGN_MASK 7 | |
389 | static inline void *align_ptr(void *ptr) | |
390 | { | |
391 | return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK); | |
392 | } | |
393 | ||
394 | /* | |
395 | * Retrieves the data payload buffer from an already allocated | |
396 | * struct dm_ioctl. | |
397 | */ | |
398 | static void *get_result_buffer(struct dm_ioctl *param, size_t param_size, | |
399 | size_t *len) | |
400 | { | |
401 | param->data_start = align_ptr(param + 1) - (void *) param; | |
402 | ||
403 | if (param->data_start < param_size) | |
404 | *len = param_size - param->data_start; | |
405 | else | |
406 | *len = 0; | |
407 | ||
408 | return ((void *) param) + param->data_start; | |
409 | } | |
410 | ||
411 | static int list_devices(struct dm_ioctl *param, size_t param_size) | |
412 | { | |
413 | unsigned int i; | |
414 | struct hash_cell *hc; | |
415 | size_t len, needed = 0; | |
416 | struct gendisk *disk; | |
417 | struct dm_name_list *nl, *old_nl = NULL; | |
418 | ||
419 | down_write(&_hash_lock); | |
420 | ||
421 | /* | |
422 | * Loop through all the devices working out how much | |
423 | * space we need. | |
424 | */ | |
425 | for (i = 0; i < NUM_BUCKETS; i++) { | |
426 | list_for_each_entry (hc, _name_buckets + i, name_list) { | |
427 | needed += sizeof(struct dm_name_list); | |
428 | needed += strlen(hc->name) + 1; | |
429 | needed += ALIGN_MASK; | |
430 | } | |
431 | } | |
432 | ||
433 | /* | |
434 | * Grab our output buffer. | |
435 | */ | |
436 | nl = get_result_buffer(param, param_size, &len); | |
437 | if (len < needed) { | |
438 | param->flags |= DM_BUFFER_FULL_FLAG; | |
439 | goto out; | |
440 | } | |
441 | param->data_size = param->data_start + needed; | |
442 | ||
443 | nl->dev = 0; /* Flags no data */ | |
444 | ||
445 | /* | |
446 | * Now loop through filling out the names. | |
447 | */ | |
448 | for (i = 0; i < NUM_BUCKETS; i++) { | |
449 | list_for_each_entry (hc, _name_buckets + i, name_list) { | |
450 | if (old_nl) | |
451 | old_nl->next = (uint32_t) ((void *) nl - | |
452 | (void *) old_nl); | |
453 | disk = dm_disk(hc->md); | |
454 | nl->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor)); | |
455 | nl->next = 0; | |
456 | strcpy(nl->name, hc->name); | |
457 | ||
458 | old_nl = nl; | |
459 | nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1); | |
460 | } | |
461 | } | |
462 | ||
463 | out: | |
464 | up_write(&_hash_lock); | |
465 | return 0; | |
466 | } | |
467 | ||
468 | static void list_version_get_needed(struct target_type *tt, void *needed_param) | |
469 | { | |
470 | size_t *needed = needed_param; | |
471 | ||
c4cc6635 | 472 | *needed += sizeof(struct dm_target_versions); |
1da177e4 | 473 | *needed += strlen(tt->name); |
1da177e4 LT |
474 | *needed += ALIGN_MASK; |
475 | } | |
476 | ||
477 | static void list_version_get_info(struct target_type *tt, void *param) | |
478 | { | |
479 | struct vers_iter *info = param; | |
480 | ||
481 | /* Check space - it might have changed since the first iteration */ | |
482 | if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 > | |
483 | info->end) { | |
484 | ||
485 | info->flags = DM_BUFFER_FULL_FLAG; | |
486 | return; | |
487 | } | |
488 | ||
489 | if (info->old_vers) | |
490 | info->old_vers->next = (uint32_t) ((void *)info->vers - | |
491 | (void *)info->old_vers); | |
492 | info->vers->version[0] = tt->version[0]; | |
493 | info->vers->version[1] = tt->version[1]; | |
494 | info->vers->version[2] = tt->version[2]; | |
495 | info->vers->next = 0; | |
496 | strcpy(info->vers->name, tt->name); | |
497 | ||
498 | info->old_vers = info->vers; | |
499 | info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1); | |
500 | } | |
501 | ||
502 | static int list_versions(struct dm_ioctl *param, size_t param_size) | |
503 | { | |
504 | size_t len, needed = 0; | |
505 | struct dm_target_versions *vers; | |
506 | struct vers_iter iter_info; | |
507 | ||
508 | /* | |
509 | * Loop through all the devices working out how much | |
510 | * space we need. | |
511 | */ | |
512 | dm_target_iterate(list_version_get_needed, &needed); | |
513 | ||
514 | /* | |
515 | * Grab our output buffer. | |
516 | */ | |
517 | vers = get_result_buffer(param, param_size, &len); | |
518 | if (len < needed) { | |
519 | param->flags |= DM_BUFFER_FULL_FLAG; | |
520 | goto out; | |
521 | } | |
522 | param->data_size = param->data_start + needed; | |
523 | ||
524 | iter_info.param_size = param_size; | |
525 | iter_info.old_vers = NULL; | |
526 | iter_info.vers = vers; | |
527 | iter_info.flags = 0; | |
528 | iter_info.end = (char *)vers+len; | |
529 | ||
530 | /* | |
531 | * Now loop through filling out the names & versions. | |
532 | */ | |
533 | dm_target_iterate(list_version_get_info, &iter_info); | |
534 | param->flags |= iter_info.flags; | |
535 | ||
536 | out: | |
537 | return 0; | |
538 | } | |
539 | ||
540 | ||
541 | ||
542 | static int check_name(const char *name) | |
543 | { | |
544 | if (strchr(name, '/')) { | |
545 | DMWARN("invalid device name"); | |
546 | return -EINVAL; | |
547 | } | |
548 | ||
549 | return 0; | |
550 | } | |
551 | ||
552 | /* | |
553 | * Fills in a dm_ioctl structure, ready for sending back to | |
554 | * userland. | |
555 | */ | |
556 | static int __dev_status(struct mapped_device *md, struct dm_ioctl *param) | |
557 | { | |
558 | struct gendisk *disk = dm_disk(md); | |
559 | struct dm_table *table; | |
1da177e4 LT |
560 | |
561 | param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG | | |
562 | DM_ACTIVE_PRESENT_FLAG); | |
563 | ||
564 | if (dm_suspended(md)) | |
565 | param->flags |= DM_SUSPEND_FLAG; | |
566 | ||
567 | param->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor)); | |
568 | ||
5c6bd75d AK |
569 | /* |
570 | * Yes, this will be out of date by the time it gets back | |
571 | * to userland, but it is still very useful for | |
572 | * debugging. | |
573 | */ | |
574 | param->open_count = dm_open_count(md); | |
1da177e4 LT |
575 | |
576 | if (disk->policy) | |
577 | param->flags |= DM_READONLY_FLAG; | |
578 | ||
579 | param->event_nr = dm_get_event_nr(md); | |
580 | ||
581 | table = dm_get_table(md); | |
582 | if (table) { | |
583 | param->flags |= DM_ACTIVE_PRESENT_FLAG; | |
584 | param->target_count = dm_table_get_num_targets(table); | |
585 | dm_table_put(table); | |
586 | } else | |
587 | param->target_count = 0; | |
588 | ||
589 | return 0; | |
590 | } | |
591 | ||
592 | static int dev_create(struct dm_ioctl *param, size_t param_size) | |
593 | { | |
2b06cfff | 594 | int r, m = DM_ANY_MINOR; |
1da177e4 LT |
595 | struct mapped_device *md; |
596 | ||
597 | r = check_name(param->name); | |
598 | if (r) | |
599 | return r; | |
600 | ||
601 | if (param->flags & DM_PERSISTENT_DEV_FLAG) | |
2b06cfff | 602 | m = MINOR(huge_decode_dev(param->dev)); |
1da177e4 | 603 | |
2b06cfff | 604 | r = dm_create(m, &md); |
1da177e4 LT |
605 | if (r) |
606 | return r; | |
607 | ||
608 | r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md); | |
609 | if (r) { | |
610 | dm_put(md); | |
611 | return r; | |
612 | } | |
613 | ||
614 | param->flags &= ~DM_INACTIVE_PRESENT_FLAG; | |
615 | ||
616 | r = __dev_status(md, param); | |
617 | dm_put(md); | |
618 | ||
619 | return r; | |
620 | } | |
621 | ||
622 | /* | |
623 | * Always use UUID for lookups if it's present, otherwise use name or dev. | |
624 | */ | |
858119e1 | 625 | static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param) |
1da177e4 | 626 | { |
9ade92a9 AK |
627 | struct mapped_device *md; |
628 | void *mdptr = NULL; | |
629 | ||
1da177e4 LT |
630 | if (*param->uuid) |
631 | return __get_uuid_cell(param->uuid); | |
9ade92a9 AK |
632 | |
633 | if (*param->name) | |
1da177e4 | 634 | return __get_name_cell(param->name); |
9ade92a9 AK |
635 | |
636 | md = dm_get_md(huge_decode_dev(param->dev)); | |
7ec75f25 | 637 | if (md) |
9ade92a9 | 638 | mdptr = dm_get_mdptr(md); |
9ade92a9 AK |
639 | |
640 | return mdptr; | |
1da177e4 LT |
641 | } |
642 | ||
858119e1 | 643 | static struct mapped_device *find_device(struct dm_ioctl *param) |
1da177e4 LT |
644 | { |
645 | struct hash_cell *hc; | |
646 | struct mapped_device *md = NULL; | |
647 | ||
648 | down_read(&_hash_lock); | |
649 | hc = __find_device_hash_cell(param); | |
650 | if (hc) { | |
651 | md = hc->md; | |
1da177e4 LT |
652 | |
653 | /* | |
654 | * Sneakily write in both the name and the uuid | |
655 | * while we have the cell. | |
656 | */ | |
657 | strncpy(param->name, hc->name, sizeof(param->name)); | |
658 | if (hc->uuid) | |
659 | strncpy(param->uuid, hc->uuid, sizeof(param->uuid)-1); | |
660 | else | |
661 | param->uuid[0] = '\0'; | |
662 | ||
663 | if (hc->new_map) | |
664 | param->flags |= DM_INACTIVE_PRESENT_FLAG; | |
665 | else | |
666 | param->flags &= ~DM_INACTIVE_PRESENT_FLAG; | |
667 | } | |
668 | up_read(&_hash_lock); | |
669 | ||
670 | return md; | |
671 | } | |
672 | ||
673 | static int dev_remove(struct dm_ioctl *param, size_t param_size) | |
674 | { | |
675 | struct hash_cell *hc; | |
7ec75f25 | 676 | struct mapped_device *md; |
5c6bd75d | 677 | int r; |
1da177e4 LT |
678 | |
679 | down_write(&_hash_lock); | |
680 | hc = __find_device_hash_cell(param); | |
681 | ||
682 | if (!hc) { | |
683 | DMWARN("device doesn't appear to be in the dev hash table."); | |
684 | up_write(&_hash_lock); | |
685 | return -ENXIO; | |
686 | } | |
687 | ||
7ec75f25 JM |
688 | md = hc->md; |
689 | ||
5c6bd75d AK |
690 | /* |
691 | * Ensure the device is not open and nothing further can open it. | |
692 | */ | |
693 | r = dm_lock_for_deletion(md); | |
694 | if (r) { | |
695 | DMWARN("unable to remove open device %s", hc->name); | |
696 | up_write(&_hash_lock); | |
697 | dm_put(md); | |
698 | return r; | |
699 | } | |
700 | ||
1da177e4 LT |
701 | __hash_remove(hc); |
702 | up_write(&_hash_lock); | |
7ec75f25 | 703 | dm_put(md); |
1da177e4 LT |
704 | param->data_size = 0; |
705 | return 0; | |
706 | } | |
707 | ||
708 | /* | |
709 | * Check a string doesn't overrun the chunk of | |
710 | * memory we copied from userland. | |
711 | */ | |
712 | static int invalid_str(char *str, void *end) | |
713 | { | |
714 | while ((void *) str < end) | |
715 | if (!*str++) | |
716 | return 0; | |
717 | ||
718 | return -EINVAL; | |
719 | } | |
720 | ||
721 | static int dev_rename(struct dm_ioctl *param, size_t param_size) | |
722 | { | |
723 | int r; | |
724 | char *new_name = (char *) param + param->data_start; | |
725 | ||
726 | if (new_name < (char *) (param + 1) || | |
727 | invalid_str(new_name, (void *) param + param_size)) { | |
728 | DMWARN("Invalid new logical volume name supplied."); | |
729 | return -EINVAL; | |
730 | } | |
731 | ||
732 | r = check_name(new_name); | |
733 | if (r) | |
734 | return r; | |
735 | ||
736 | param->data_size = 0; | |
737 | return dm_hash_rename(param->name, new_name); | |
738 | } | |
739 | ||
3ac51e74 DW |
740 | static int dev_set_geometry(struct dm_ioctl *param, size_t param_size) |
741 | { | |
742 | int r = -EINVAL, x; | |
743 | struct mapped_device *md; | |
744 | struct hd_geometry geometry; | |
745 | unsigned long indata[4]; | |
746 | char *geostr = (char *) param + param->data_start; | |
747 | ||
748 | md = find_device(param); | |
749 | if (!md) | |
750 | return -ENXIO; | |
751 | ||
752 | if (geostr < (char *) (param + 1) || | |
753 | invalid_str(geostr, (void *) param + param_size)) { | |
754 | DMWARN("Invalid geometry supplied."); | |
755 | goto out; | |
756 | } | |
757 | ||
758 | x = sscanf(geostr, "%lu %lu %lu %lu", indata, | |
759 | indata + 1, indata + 2, indata + 3); | |
760 | ||
761 | if (x != 4) { | |
762 | DMWARN("Unable to interpret geometry settings."); | |
763 | goto out; | |
764 | } | |
765 | ||
766 | if (indata[0] > 65535 || indata[1] > 255 || | |
767 | indata[2] > 255 || indata[3] > ULONG_MAX) { | |
768 | DMWARN("Geometry exceeds range limits."); | |
769 | goto out; | |
770 | } | |
771 | ||
772 | geometry.cylinders = indata[0]; | |
773 | geometry.heads = indata[1]; | |
774 | geometry.sectors = indata[2]; | |
775 | geometry.start = indata[3]; | |
776 | ||
777 | r = dm_set_geometry(md, &geometry); | |
778 | if (!r) | |
779 | r = __dev_status(md, param); | |
780 | ||
781 | param->data_size = 0; | |
782 | ||
783 | out: | |
784 | dm_put(md); | |
785 | return r; | |
786 | } | |
787 | ||
1da177e4 LT |
788 | static int do_suspend(struct dm_ioctl *param) |
789 | { | |
790 | int r = 0; | |
6da487dc | 791 | int do_lockfs = 1; |
1da177e4 LT |
792 | struct mapped_device *md; |
793 | ||
794 | md = find_device(param); | |
795 | if (!md) | |
796 | return -ENXIO; | |
797 | ||
6da487dc AK |
798 | if (param->flags & DM_SKIP_LOCKFS_FLAG) |
799 | do_lockfs = 0; | |
800 | ||
1da177e4 | 801 | if (!dm_suspended(md)) |
6da487dc | 802 | r = dm_suspend(md, do_lockfs); |
1da177e4 LT |
803 | |
804 | if (!r) | |
805 | r = __dev_status(md, param); | |
806 | ||
807 | dm_put(md); | |
808 | return r; | |
809 | } | |
810 | ||
811 | static int do_resume(struct dm_ioctl *param) | |
812 | { | |
813 | int r = 0; | |
6da487dc | 814 | int do_lockfs = 1; |
1da177e4 LT |
815 | struct hash_cell *hc; |
816 | struct mapped_device *md; | |
817 | struct dm_table *new_map; | |
818 | ||
819 | down_write(&_hash_lock); | |
820 | ||
821 | hc = __find_device_hash_cell(param); | |
822 | if (!hc) { | |
823 | DMWARN("device doesn't appear to be in the dev hash table."); | |
824 | up_write(&_hash_lock); | |
825 | return -ENXIO; | |
826 | } | |
827 | ||
828 | md = hc->md; | |
1da177e4 LT |
829 | |
830 | new_map = hc->new_map; | |
831 | hc->new_map = NULL; | |
832 | param->flags &= ~DM_INACTIVE_PRESENT_FLAG; | |
833 | ||
834 | up_write(&_hash_lock); | |
835 | ||
836 | /* Do we need to load a new map ? */ | |
837 | if (new_map) { | |
838 | /* Suspend if it isn't already suspended */ | |
6da487dc AK |
839 | if (param->flags & DM_SKIP_LOCKFS_FLAG) |
840 | do_lockfs = 0; | |
1da177e4 | 841 | if (!dm_suspended(md)) |
6da487dc | 842 | dm_suspend(md, do_lockfs); |
1da177e4 LT |
843 | |
844 | r = dm_swap_table(md, new_map); | |
845 | if (r) { | |
846 | dm_put(md); | |
847 | dm_table_put(new_map); | |
848 | return r; | |
849 | } | |
850 | ||
851 | if (dm_table_get_mode(new_map) & FMODE_WRITE) | |
852 | set_disk_ro(dm_disk(md), 0); | |
853 | else | |
854 | set_disk_ro(dm_disk(md), 1); | |
855 | ||
856 | dm_table_put(new_map); | |
857 | } | |
858 | ||
859 | if (dm_suspended(md)) | |
860 | r = dm_resume(md); | |
861 | ||
862 | if (!r) | |
863 | r = __dev_status(md, param); | |
864 | ||
865 | dm_put(md); | |
866 | return r; | |
867 | } | |
868 | ||
869 | /* | |
870 | * Set or unset the suspension state of a device. | |
871 | * If the device already is in the requested state we just return its status. | |
872 | */ | |
873 | static int dev_suspend(struct dm_ioctl *param, size_t param_size) | |
874 | { | |
875 | if (param->flags & DM_SUSPEND_FLAG) | |
876 | return do_suspend(param); | |
877 | ||
878 | return do_resume(param); | |
879 | } | |
880 | ||
881 | /* | |
882 | * Copies device info back to user space, used by | |
883 | * the create and info ioctls. | |
884 | */ | |
885 | static int dev_status(struct dm_ioctl *param, size_t param_size) | |
886 | { | |
887 | int r; | |
888 | struct mapped_device *md; | |
889 | ||
890 | md = find_device(param); | |
891 | if (!md) | |
892 | return -ENXIO; | |
893 | ||
894 | r = __dev_status(md, param); | |
895 | dm_put(md); | |
896 | return r; | |
897 | } | |
898 | ||
899 | /* | |
900 | * Build up the status struct for each target | |
901 | */ | |
902 | static void retrieve_status(struct dm_table *table, | |
903 | struct dm_ioctl *param, size_t param_size) | |
904 | { | |
905 | unsigned int i, num_targets; | |
906 | struct dm_target_spec *spec; | |
907 | char *outbuf, *outptr; | |
908 | status_type_t type; | |
909 | size_t remaining, len, used = 0; | |
910 | ||
911 | outptr = outbuf = get_result_buffer(param, param_size, &len); | |
912 | ||
913 | if (param->flags & DM_STATUS_TABLE_FLAG) | |
914 | type = STATUSTYPE_TABLE; | |
915 | else | |
916 | type = STATUSTYPE_INFO; | |
917 | ||
918 | /* Get all the target info */ | |
919 | num_targets = dm_table_get_num_targets(table); | |
920 | for (i = 0; i < num_targets; i++) { | |
921 | struct dm_target *ti = dm_table_get_target(table, i); | |
922 | ||
923 | remaining = len - (outptr - outbuf); | |
924 | if (remaining <= sizeof(struct dm_target_spec)) { | |
925 | param->flags |= DM_BUFFER_FULL_FLAG; | |
926 | break; | |
927 | } | |
928 | ||
929 | spec = (struct dm_target_spec *) outptr; | |
930 | ||
931 | spec->status = 0; | |
932 | spec->sector_start = ti->begin; | |
933 | spec->length = ti->len; | |
934 | strncpy(spec->target_type, ti->type->name, | |
935 | sizeof(spec->target_type)); | |
936 | ||
937 | outptr += sizeof(struct dm_target_spec); | |
938 | remaining = len - (outptr - outbuf); | |
939 | if (remaining <= 0) { | |
940 | param->flags |= DM_BUFFER_FULL_FLAG; | |
941 | break; | |
942 | } | |
943 | ||
944 | /* Get the status/table string from the target driver */ | |
945 | if (ti->type->status) { | |
946 | if (ti->type->status(ti, type, outptr, remaining)) { | |
947 | param->flags |= DM_BUFFER_FULL_FLAG; | |
948 | break; | |
949 | } | |
950 | } else | |
951 | outptr[0] = '\0'; | |
952 | ||
953 | outptr += strlen(outptr) + 1; | |
954 | used = param->data_start + (outptr - outbuf); | |
955 | ||
956 | outptr = align_ptr(outptr); | |
957 | spec->next = outptr - outbuf; | |
958 | } | |
959 | ||
960 | if (used) | |
961 | param->data_size = used; | |
962 | ||
963 | param->target_count = num_targets; | |
964 | } | |
965 | ||
966 | /* | |
967 | * Wait for a device to report an event | |
968 | */ | |
969 | static int dev_wait(struct dm_ioctl *param, size_t param_size) | |
970 | { | |
971 | int r; | |
972 | struct mapped_device *md; | |
973 | struct dm_table *table; | |
974 | ||
975 | md = find_device(param); | |
976 | if (!md) | |
977 | return -ENXIO; | |
978 | ||
979 | /* | |
980 | * Wait for a notification event | |
981 | */ | |
982 | if (dm_wait_event(md, param->event_nr)) { | |
983 | r = -ERESTARTSYS; | |
984 | goto out; | |
985 | } | |
986 | ||
987 | /* | |
988 | * The userland program is going to want to know what | |
989 | * changed to trigger the event, so we may as well tell | |
990 | * him and save an ioctl. | |
991 | */ | |
992 | r = __dev_status(md, param); | |
993 | if (r) | |
994 | goto out; | |
995 | ||
996 | table = dm_get_table(md); | |
997 | if (table) { | |
998 | retrieve_status(table, param, param_size); | |
999 | dm_table_put(table); | |
1000 | } | |
1001 | ||
1002 | out: | |
1003 | dm_put(md); | |
1004 | return r; | |
1005 | } | |
1006 | ||
1007 | static inline int get_mode(struct dm_ioctl *param) | |
1008 | { | |
1009 | int mode = FMODE_READ | FMODE_WRITE; | |
1010 | ||
1011 | if (param->flags & DM_READONLY_FLAG) | |
1012 | mode = FMODE_READ; | |
1013 | ||
1014 | return mode; | |
1015 | } | |
1016 | ||
1017 | static int next_target(struct dm_target_spec *last, uint32_t next, void *end, | |
1018 | struct dm_target_spec **spec, char **target_params) | |
1019 | { | |
1020 | *spec = (struct dm_target_spec *) ((unsigned char *) last + next); | |
1021 | *target_params = (char *) (*spec + 1); | |
1022 | ||
1023 | if (*spec < (last + 1)) | |
1024 | return -EINVAL; | |
1025 | ||
1026 | return invalid_str(*target_params, end); | |
1027 | } | |
1028 | ||
1029 | static int populate_table(struct dm_table *table, | |
1030 | struct dm_ioctl *param, size_t param_size) | |
1031 | { | |
1032 | int r; | |
1033 | unsigned int i = 0; | |
1034 | struct dm_target_spec *spec = (struct dm_target_spec *) param; | |
1035 | uint32_t next = param->data_start; | |
1036 | void *end = (void *) param + param_size; | |
1037 | char *target_params; | |
1038 | ||
1039 | if (!param->target_count) { | |
1040 | DMWARN("populate_table: no targets specified"); | |
1041 | return -EINVAL; | |
1042 | } | |
1043 | ||
1044 | for (i = 0; i < param->target_count; i++) { | |
1045 | ||
1046 | r = next_target(spec, next, end, &spec, &target_params); | |
1047 | if (r) { | |
1048 | DMWARN("unable to find target"); | |
1049 | return r; | |
1050 | } | |
1051 | ||
1052 | r = dm_table_add_target(table, spec->target_type, | |
1053 | (sector_t) spec->sector_start, | |
1054 | (sector_t) spec->length, | |
1055 | target_params); | |
1056 | if (r) { | |
1057 | DMWARN("error adding target to table"); | |
1058 | return r; | |
1059 | } | |
1060 | ||
1061 | next = spec->next; | |
1062 | } | |
1063 | ||
1064 | return dm_table_complete(table); | |
1065 | } | |
1066 | ||
1067 | static int table_load(struct dm_ioctl *param, size_t param_size) | |
1068 | { | |
1069 | int r; | |
1070 | struct hash_cell *hc; | |
1071 | struct dm_table *t; | |
1134e5ae MA |
1072 | struct mapped_device *md; |
1073 | ||
1074 | md = find_device(param); | |
1075 | if (!md) | |
1076 | return -ENXIO; | |
1da177e4 | 1077 | |
1134e5ae | 1078 | r = dm_table_create(&t, get_mode(param), param->target_count, md); |
1da177e4 | 1079 | if (r) |
1134e5ae | 1080 | goto out; |
1da177e4 LT |
1081 | |
1082 | r = populate_table(t, param, param_size); | |
1083 | if (r) { | |
1084 | dm_table_put(t); | |
1134e5ae | 1085 | goto out; |
1da177e4 LT |
1086 | } |
1087 | ||
1088 | down_write(&_hash_lock); | |
1134e5ae MA |
1089 | hc = dm_get_mdptr(md); |
1090 | if (!hc || hc->md != md) { | |
1091 | DMWARN("device has been removed from the dev hash table."); | |
b6fcc80d | 1092 | dm_table_put(t); |
1134e5ae MA |
1093 | up_write(&_hash_lock); |
1094 | r = -ENXIO; | |
1095 | goto out; | |
1da177e4 LT |
1096 | } |
1097 | ||
1098 | if (hc->new_map) | |
1099 | dm_table_put(hc->new_map); | |
1100 | hc->new_map = t; | |
1134e5ae MA |
1101 | up_write(&_hash_lock); |
1102 | ||
1da177e4 | 1103 | param->flags |= DM_INACTIVE_PRESENT_FLAG; |
1134e5ae MA |
1104 | r = __dev_status(md, param); |
1105 | ||
1106 | out: | |
1107 | dm_put(md); | |
1da177e4 | 1108 | |
1da177e4 LT |
1109 | return r; |
1110 | } | |
1111 | ||
1112 | static int table_clear(struct dm_ioctl *param, size_t param_size) | |
1113 | { | |
1114 | int r; | |
1115 | struct hash_cell *hc; | |
7ec75f25 | 1116 | struct mapped_device *md; |
1da177e4 LT |
1117 | |
1118 | down_write(&_hash_lock); | |
1119 | ||
1120 | hc = __find_device_hash_cell(param); | |
1121 | if (!hc) { | |
1122 | DMWARN("device doesn't appear to be in the dev hash table."); | |
1123 | up_write(&_hash_lock); | |
1124 | return -ENXIO; | |
1125 | } | |
1126 | ||
1127 | if (hc->new_map) { | |
1128 | dm_table_put(hc->new_map); | |
1129 | hc->new_map = NULL; | |
1130 | } | |
1131 | ||
1132 | param->flags &= ~DM_INACTIVE_PRESENT_FLAG; | |
1133 | ||
1134 | r = __dev_status(hc->md, param); | |
7ec75f25 | 1135 | md = hc->md; |
1da177e4 | 1136 | up_write(&_hash_lock); |
7ec75f25 | 1137 | dm_put(md); |
1da177e4 LT |
1138 | return r; |
1139 | } | |
1140 | ||
1141 | /* | |
1142 | * Retrieves a list of devices used by a particular dm device. | |
1143 | */ | |
1144 | static void retrieve_deps(struct dm_table *table, | |
1145 | struct dm_ioctl *param, size_t param_size) | |
1146 | { | |
1147 | unsigned int count = 0; | |
1148 | struct list_head *tmp; | |
1149 | size_t len, needed; | |
1150 | struct dm_dev *dd; | |
1151 | struct dm_target_deps *deps; | |
1152 | ||
1153 | deps = get_result_buffer(param, param_size, &len); | |
1154 | ||
1155 | /* | |
1156 | * Count the devices. | |
1157 | */ | |
1158 | list_for_each (tmp, dm_table_get_devices(table)) | |
1159 | count++; | |
1160 | ||
1161 | /* | |
1162 | * Check we have enough space. | |
1163 | */ | |
1164 | needed = sizeof(*deps) + (sizeof(*deps->dev) * count); | |
1165 | if (len < needed) { | |
1166 | param->flags |= DM_BUFFER_FULL_FLAG; | |
1167 | return; | |
1168 | } | |
1169 | ||
1170 | /* | |
1171 | * Fill in the devices. | |
1172 | */ | |
1173 | deps->count = count; | |
1174 | count = 0; | |
1175 | list_for_each_entry (dd, dm_table_get_devices(table), list) | |
1176 | deps->dev[count++] = huge_encode_dev(dd->bdev->bd_dev); | |
1177 | ||
1178 | param->data_size = param->data_start + needed; | |
1179 | } | |
1180 | ||
1181 | static int table_deps(struct dm_ioctl *param, size_t param_size) | |
1182 | { | |
1183 | int r = 0; | |
1184 | struct mapped_device *md; | |
1185 | struct dm_table *table; | |
1186 | ||
1187 | md = find_device(param); | |
1188 | if (!md) | |
1189 | return -ENXIO; | |
1190 | ||
1191 | r = __dev_status(md, param); | |
1192 | if (r) | |
1193 | goto out; | |
1194 | ||
1195 | table = dm_get_table(md); | |
1196 | if (table) { | |
1197 | retrieve_deps(table, param, param_size); | |
1198 | dm_table_put(table); | |
1199 | } | |
1200 | ||
1201 | out: | |
1202 | dm_put(md); | |
1203 | return r; | |
1204 | } | |
1205 | ||
1206 | /* | |
1207 | * Return the status of a device as a text string for each | |
1208 | * target. | |
1209 | */ | |
1210 | static int table_status(struct dm_ioctl *param, size_t param_size) | |
1211 | { | |
1212 | int r; | |
1213 | struct mapped_device *md; | |
1214 | struct dm_table *table; | |
1215 | ||
1216 | md = find_device(param); | |
1217 | if (!md) | |
1218 | return -ENXIO; | |
1219 | ||
1220 | r = __dev_status(md, param); | |
1221 | if (r) | |
1222 | goto out; | |
1223 | ||
1224 | table = dm_get_table(md); | |
1225 | if (table) { | |
1226 | retrieve_status(table, param, param_size); | |
1227 | dm_table_put(table); | |
1228 | } | |
1229 | ||
1230 | out: | |
1231 | dm_put(md); | |
1232 | return r; | |
1233 | } | |
1234 | ||
1235 | /* | |
1236 | * Pass a message to the target that's at the supplied device offset. | |
1237 | */ | |
1238 | static int target_message(struct dm_ioctl *param, size_t param_size) | |
1239 | { | |
1240 | int r, argc; | |
1241 | char **argv; | |
1242 | struct mapped_device *md; | |
1243 | struct dm_table *table; | |
1244 | struct dm_target *ti; | |
1245 | struct dm_target_msg *tmsg = (void *) param + param->data_start; | |
1246 | ||
1247 | md = find_device(param); | |
1248 | if (!md) | |
1249 | return -ENXIO; | |
1250 | ||
1251 | r = __dev_status(md, param); | |
1252 | if (r) | |
1253 | goto out; | |
1254 | ||
1255 | if (tmsg < (struct dm_target_msg *) (param + 1) || | |
1256 | invalid_str(tmsg->message, (void *) param + param_size)) { | |
1257 | DMWARN("Invalid target message parameters."); | |
1258 | r = -EINVAL; | |
1259 | goto out; | |
1260 | } | |
1261 | ||
1262 | r = dm_split_args(&argc, &argv, tmsg->message); | |
1263 | if (r) { | |
1264 | DMWARN("Failed to split target message parameters"); | |
1265 | goto out; | |
1266 | } | |
1267 | ||
1268 | table = dm_get_table(md); | |
1269 | if (!table) | |
1270 | goto out_argv; | |
1271 | ||
1272 | if (tmsg->sector >= dm_table_get_size(table)) { | |
1273 | DMWARN("Target message sector outside device."); | |
1274 | r = -EINVAL; | |
1275 | goto out_table; | |
1276 | } | |
1277 | ||
1278 | ti = dm_table_find_target(table, tmsg->sector); | |
1279 | if (ti->type->message) | |
1280 | r = ti->type->message(ti, argc, argv); | |
1281 | else { | |
1282 | DMWARN("Target type does not support messages"); | |
1283 | r = -EINVAL; | |
1284 | } | |
1285 | ||
1286 | out_table: | |
1287 | dm_table_put(table); | |
1288 | out_argv: | |
1289 | kfree(argv); | |
1290 | out: | |
1291 | param->data_size = 0; | |
1292 | dm_put(md); | |
1293 | return r; | |
1294 | } | |
1295 | ||
1296 | /*----------------------------------------------------------------- | |
1297 | * Implementation of open/close/ioctl on the special char | |
1298 | * device. | |
1299 | *---------------------------------------------------------------*/ | |
1300 | static ioctl_fn lookup_ioctl(unsigned int cmd) | |
1301 | { | |
1302 | static struct { | |
1303 | int cmd; | |
1304 | ioctl_fn fn; | |
1305 | } _ioctls[] = { | |
1306 | {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */ | |
1307 | {DM_REMOVE_ALL_CMD, remove_all}, | |
1308 | {DM_LIST_DEVICES_CMD, list_devices}, | |
1309 | ||
1310 | {DM_DEV_CREATE_CMD, dev_create}, | |
1311 | {DM_DEV_REMOVE_CMD, dev_remove}, | |
1312 | {DM_DEV_RENAME_CMD, dev_rename}, | |
1313 | {DM_DEV_SUSPEND_CMD, dev_suspend}, | |
1314 | {DM_DEV_STATUS_CMD, dev_status}, | |
1315 | {DM_DEV_WAIT_CMD, dev_wait}, | |
1316 | ||
1317 | {DM_TABLE_LOAD_CMD, table_load}, | |
1318 | {DM_TABLE_CLEAR_CMD, table_clear}, | |
1319 | {DM_TABLE_DEPS_CMD, table_deps}, | |
1320 | {DM_TABLE_STATUS_CMD, table_status}, | |
1321 | ||
1322 | {DM_LIST_VERSIONS_CMD, list_versions}, | |
1323 | ||
3ac51e74 DW |
1324 | {DM_TARGET_MSG_CMD, target_message}, |
1325 | {DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry} | |
1da177e4 LT |
1326 | }; |
1327 | ||
1328 | return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn; | |
1329 | } | |
1330 | ||
1331 | /* | |
1332 | * As well as checking the version compatibility this always | |
1333 | * copies the kernel interface version out. | |
1334 | */ | |
1335 | static int check_version(unsigned int cmd, struct dm_ioctl __user *user) | |
1336 | { | |
1337 | uint32_t version[3]; | |
1338 | int r = 0; | |
1339 | ||
1340 | if (copy_from_user(version, user->version, sizeof(version))) | |
1341 | return -EFAULT; | |
1342 | ||
1343 | if ((DM_VERSION_MAJOR != version[0]) || | |
1344 | (DM_VERSION_MINOR < version[1])) { | |
1345 | DMWARN("ioctl interface mismatch: " | |
1346 | "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)", | |
1347 | DM_VERSION_MAJOR, DM_VERSION_MINOR, | |
1348 | DM_VERSION_PATCHLEVEL, | |
1349 | version[0], version[1], version[2], cmd); | |
1350 | r = -EINVAL; | |
1351 | } | |
1352 | ||
1353 | /* | |
1354 | * Fill in the kernel version. | |
1355 | */ | |
1356 | version[0] = DM_VERSION_MAJOR; | |
1357 | version[1] = DM_VERSION_MINOR; | |
1358 | version[2] = DM_VERSION_PATCHLEVEL; | |
1359 | if (copy_to_user(user->version, version, sizeof(version))) | |
1360 | return -EFAULT; | |
1361 | ||
1362 | return r; | |
1363 | } | |
1364 | ||
1365 | static void free_params(struct dm_ioctl *param) | |
1366 | { | |
1367 | vfree(param); | |
1368 | } | |
1369 | ||
1370 | static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param) | |
1371 | { | |
1372 | struct dm_ioctl tmp, *dmi; | |
1373 | ||
1374 | if (copy_from_user(&tmp, user, sizeof(tmp))) | |
1375 | return -EFAULT; | |
1376 | ||
1377 | if (tmp.data_size < sizeof(tmp)) | |
1378 | return -EINVAL; | |
1379 | ||
1380 | dmi = (struct dm_ioctl *) vmalloc(tmp.data_size); | |
1381 | if (!dmi) | |
1382 | return -ENOMEM; | |
1383 | ||
1384 | if (copy_from_user(dmi, user, tmp.data_size)) { | |
1385 | vfree(dmi); | |
1386 | return -EFAULT; | |
1387 | } | |
1388 | ||
1389 | *param = dmi; | |
1390 | return 0; | |
1391 | } | |
1392 | ||
1393 | static int validate_params(uint cmd, struct dm_ioctl *param) | |
1394 | { | |
1395 | /* Always clear this flag */ | |
1396 | param->flags &= ~DM_BUFFER_FULL_FLAG; | |
1397 | ||
1398 | /* Ignores parameters */ | |
1399 | if (cmd == DM_REMOVE_ALL_CMD || | |
1400 | cmd == DM_LIST_DEVICES_CMD || | |
1401 | cmd == DM_LIST_VERSIONS_CMD) | |
1402 | return 0; | |
1403 | ||
1404 | if ((cmd == DM_DEV_CREATE_CMD)) { | |
1405 | if (!*param->name) { | |
1406 | DMWARN("name not supplied when creating device"); | |
1407 | return -EINVAL; | |
1408 | } | |
1409 | } else if ((*param->uuid && *param->name)) { | |
1410 | DMWARN("only supply one of name or uuid, cmd(%u)", cmd); | |
1411 | return -EINVAL; | |
1412 | } | |
1413 | ||
1414 | /* Ensure strings are terminated */ | |
1415 | param->name[DM_NAME_LEN - 1] = '\0'; | |
1416 | param->uuid[DM_UUID_LEN - 1] = '\0'; | |
1417 | ||
1418 | return 0; | |
1419 | } | |
1420 | ||
1421 | static int ctl_ioctl(struct inode *inode, struct file *file, | |
1422 | uint command, ulong u) | |
1423 | { | |
1424 | int r = 0; | |
1425 | unsigned int cmd; | |
1426 | struct dm_ioctl *param; | |
1427 | struct dm_ioctl __user *user = (struct dm_ioctl __user *) u; | |
1428 | ioctl_fn fn = NULL; | |
1429 | size_t param_size; | |
1430 | ||
1431 | /* only root can play with this */ | |
1432 | if (!capable(CAP_SYS_ADMIN)) | |
1433 | return -EACCES; | |
1434 | ||
1435 | if (_IOC_TYPE(command) != DM_IOCTL) | |
1436 | return -ENOTTY; | |
1437 | ||
1438 | cmd = _IOC_NR(command); | |
1439 | ||
1440 | /* | |
1441 | * Check the interface version passed in. This also | |
1442 | * writes out the kernel's interface version. | |
1443 | */ | |
1444 | r = check_version(cmd, user); | |
1445 | if (r) | |
1446 | return r; | |
1447 | ||
1448 | /* | |
1449 | * Nothing more to do for the version command. | |
1450 | */ | |
1451 | if (cmd == DM_VERSION_CMD) | |
1452 | return 0; | |
1453 | ||
1454 | fn = lookup_ioctl(cmd); | |
1455 | if (!fn) { | |
1456 | DMWARN("dm_ctl_ioctl: unknown command 0x%x", command); | |
1457 | return -ENOTTY; | |
1458 | } | |
1459 | ||
1460 | /* | |
1461 | * Trying to avoid low memory issues when a device is | |
1462 | * suspended. | |
1463 | */ | |
1464 | current->flags |= PF_MEMALLOC; | |
1465 | ||
1466 | /* | |
1467 | * Copy the parameters into kernel space. | |
1468 | */ | |
1469 | r = copy_params(user, ¶m); | |
1da177e4 | 1470 | |
dab6a429 AK |
1471 | current->flags &= ~PF_MEMALLOC; |
1472 | ||
1473 | if (r) | |
1474 | return r; | |
1da177e4 LT |
1475 | |
1476 | r = validate_params(cmd, param); | |
1477 | if (r) | |
1478 | goto out; | |
1479 | ||
1480 | param_size = param->data_size; | |
1481 | param->data_size = sizeof(*param); | |
1482 | r = fn(param, param_size); | |
1483 | ||
1484 | /* | |
1485 | * Copy the results back to userland. | |
1486 | */ | |
1487 | if (!r && copy_to_user(user, param, param->data_size)) | |
1488 | r = -EFAULT; | |
1489 | ||
1490 | out: | |
1491 | free_params(param); | |
1da177e4 LT |
1492 | return r; |
1493 | } | |
1494 | ||
1495 | static struct file_operations _ctl_fops = { | |
1496 | .ioctl = ctl_ioctl, | |
1497 | .owner = THIS_MODULE, | |
1498 | }; | |
1499 | ||
1500 | static struct miscdevice _dm_misc = { | |
1501 | .minor = MISC_DYNAMIC_MINOR, | |
1502 | .name = DM_NAME, | |
1503 | .devfs_name = "mapper/control", | |
1504 | .fops = &_ctl_fops | |
1505 | }; | |
1506 | ||
1507 | /* | |
1508 | * Create misc character device and link to DM_DIR/control. | |
1509 | */ | |
1510 | int __init dm_interface_init(void) | |
1511 | { | |
1512 | int r; | |
1513 | ||
1514 | r = dm_hash_init(); | |
1515 | if (r) | |
1516 | return r; | |
1517 | ||
1518 | r = misc_register(&_dm_misc); | |
1519 | if (r) { | |
1520 | DMERR("misc_register failed for control device"); | |
1521 | dm_hash_exit(); | |
1522 | return r; | |
1523 | } | |
1524 | ||
1525 | DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR, | |
1526 | DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA, | |
1527 | DM_DRIVER_EMAIL); | |
1528 | return 0; | |
1529 | } | |
1530 | ||
1531 | void dm_interface_exit(void) | |
1532 | { | |
1533 | if (misc_deregister(&_dm_misc) < 0) | |
1534 | DMERR("misc_deregister failed for control device"); | |
1535 | ||
1536 | dm_hash_exit(); | |
1537 | } |