2 * Copyright (C) 2001, 2002 Sistina Software (UK) Limited.
3 * Copyright (C) 2004 - 2006 Red Hat, Inc. All rights reserved.
5 * This file is released under the GPL.
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>
18 #include <linux/hdreg.h>
20 #include <asm/uaccess.h>
22 #define DM_MSG_PREFIX "ioctl"
23 #define DM_DRIVER_EMAIL "dm-devel@redhat.com"
25 /*-----------------------------------------------------------------
26 * The ioctl interface needs to be able to look up devices by
28 *---------------------------------------------------------------*/
30 struct list_head name_list;
31 struct list_head uuid_list;
35 struct mapped_device *md;
36 struct dm_table *new_map;
41 struct dm_target_versions *vers, *old_vers;
47 #define NUM_BUCKETS 64
48 #define MASK_BUCKETS (NUM_BUCKETS - 1)
49 static struct list_head _name_buckets[NUM_BUCKETS];
50 static struct list_head _uuid_buckets[NUM_BUCKETS];
52 static void dm_hash_remove_all(int keep_open_devices);
55 * Guards access to both hash tables.
57 static DECLARE_RWSEM(_hash_lock);
59 static void init_buckets(struct list_head *buckets)
63 for (i = 0; i < NUM_BUCKETS; i++)
64 INIT_LIST_HEAD(buckets + i);
67 static int dm_hash_init(void)
69 init_buckets(_name_buckets);
70 init_buckets(_uuid_buckets);
74 static void dm_hash_exit(void)
76 dm_hash_remove_all(0);
80 /*-----------------------------------------------------------------
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)
87 const unsigned int hash_mult = 2654435387U;
91 h = (h + (unsigned int) *str++) * hash_mult;
93 return h & MASK_BUCKETS;
96 /*-----------------------------------------------------------------
97 * Code for looking up a device by name
98 *---------------------------------------------------------------*/
99 static struct hash_cell *__get_name_cell(const char *str)
101 struct hash_cell *hc;
102 unsigned int h = hash_str(str);
104 list_for_each_entry (hc, _name_buckets + h, name_list)
105 if (!strcmp(hc->name, str)) {
113 static struct hash_cell *__get_uuid_cell(const char *str)
115 struct hash_cell *hc;
116 unsigned int h = hash_str(str);
118 list_for_each_entry (hc, _uuid_buckets + h, uuid_list)
119 if (!strcmp(hc->uuid, str)) {
127 /*-----------------------------------------------------------------
128 * Inserting, removing and renaming a device.
129 *---------------------------------------------------------------*/
130 static struct hash_cell *alloc_cell(const char *name, const char *uuid,
131 struct mapped_device *md)
133 struct hash_cell *hc;
135 hc = kmalloc(sizeof(*hc), GFP_KERNEL);
139 hc->name = kstrdup(name, GFP_KERNEL);
149 hc->uuid = kstrdup(uuid, GFP_KERNEL);
157 INIT_LIST_HEAD(&hc->name_list);
158 INIT_LIST_HEAD(&hc->uuid_list);
164 static void free_cell(struct hash_cell *hc)
176 static int register_with_devfs(struct hash_cell *hc)
178 struct gendisk *disk = dm_disk(hc->md);
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);
186 static int unregister_with_devfs(struct hash_cell *hc)
188 devfs_remove(DM_DIR"/%s", hc->name);
193 * The kdev_t and uuid of a device can never change once it is
194 * initially inserted.
196 static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
198 struct hash_cell *cell, *hc;
201 * Allocate the new cells.
203 cell = alloc_cell(name, uuid, md);
208 * Insert the cell into both hash tables.
210 down_write(&_hash_lock);
211 hc = __get_name_cell(name);
217 list_add(&cell->name_list, _name_buckets + hash_str(name));
220 hc = __get_uuid_cell(uuid);
222 list_del(&cell->name_list);
226 list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
228 register_with_devfs(cell);
230 dm_set_mdptr(md, cell);
231 up_write(&_hash_lock);
236 up_write(&_hash_lock);
241 static void __hash_remove(struct hash_cell *hc)
243 struct dm_table *table;
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);
251 table = dm_get_table(hc->md);
253 dm_table_event(table);
258 dm_table_put(hc->new_map);
263 static void dm_hash_remove_all(int keep_open_devices)
265 int i, dev_skipped, dev_removed;
266 struct hash_cell *hc;
267 struct list_head *tmp, *n;
269 down_write(&_hash_lock);
272 dev_skipped = dev_removed = 0;
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);
277 if (keep_open_devices &&
278 dm_lock_for_deletion(hc->md)) {
288 * Some mapped devices may be using other mapped devices, so if any
289 * still exist, repeat until we make no further progress.
295 DMWARN("remove_all left %d open device(s)", dev_skipped);
298 up_write(&_hash_lock);
301 static int dm_hash_rename(const char *old, const char *new)
303 char *new_name, *old_name;
304 struct hash_cell *hc;
305 struct dm_table *table;
310 new_name = kstrdup(new, GFP_KERNEL);
314 down_write(&_hash_lock);
319 hc = __get_name_cell(new);
321 DMWARN("asked to rename to an already existing name %s -> %s",
324 up_write(&_hash_lock);
330 * Is there such a device as 'old' ?
332 hc = __get_name_cell(old);
334 DMWARN("asked to rename a non existent device %s -> %s",
336 up_write(&_hash_lock);
342 * rename and move the name cell.
344 unregister_with_devfs(hc);
346 list_del(&hc->name_list);
349 list_add(&hc->name_list, _name_buckets + hash_str(new_name));
351 /* rename the device node in devfs */
352 register_with_devfs(hc);
355 * Wake up any dm event waiters.
357 table = dm_get_table(hc->md);
359 dm_table_event(table);
364 up_write(&_hash_lock);
369 /*-----------------------------------------------------------------
370 * Implementation of the ioctl commands
371 *---------------------------------------------------------------*/
373 * All the ioctl commands get dispatched to functions with this
376 typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size);
378 static int remove_all(struct dm_ioctl *param, size_t param_size)
380 dm_hash_remove_all(1);
381 param->data_size = 0;
386 * Round up the ptr to an 8-byte boundary.
389 static inline void *align_ptr(void *ptr)
391 return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK);
395 * Retrieves the data payload buffer from an already allocated
398 static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
401 param->data_start = align_ptr(param + 1) - (void *) param;
403 if (param->data_start < param_size)
404 *len = param_size - param->data_start;
408 return ((void *) param) + param->data_start;
411 static int list_devices(struct dm_ioctl *param, size_t param_size)
414 struct hash_cell *hc;
415 size_t len, needed = 0;
416 struct gendisk *disk;
417 struct dm_name_list *nl, *old_nl = NULL;
419 down_write(&_hash_lock);
422 * Loop through all the devices working out how much
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;
434 * Grab our output buffer.
436 nl = get_result_buffer(param, param_size, &len);
438 param->flags |= DM_BUFFER_FULL_FLAG;
441 param->data_size = param->data_start + needed;
443 nl->dev = 0; /* Flags no data */
446 * Now loop through filling out the names.
448 for (i = 0; i < NUM_BUCKETS; i++) {
449 list_for_each_entry (hc, _name_buckets + i, name_list) {
451 old_nl->next = (uint32_t) ((void *) nl -
453 disk = dm_disk(hc->md);
454 nl->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
456 strcpy(nl->name, hc->name);
459 nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1);
464 up_write(&_hash_lock);
468 static void list_version_get_needed(struct target_type *tt, void *needed_param)
470 size_t *needed = needed_param;
472 *needed += sizeof(struct dm_target_versions);
473 *needed += strlen(tt->name);
474 *needed += ALIGN_MASK;
477 static void list_version_get_info(struct target_type *tt, void *param)
479 struct vers_iter *info = param;
481 /* Check space - it might have changed since the first iteration */
482 if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 >
485 info->flags = DM_BUFFER_FULL_FLAG;
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);
498 info->old_vers = info->vers;
499 info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
502 static int list_versions(struct dm_ioctl *param, size_t param_size)
504 size_t len, needed = 0;
505 struct dm_target_versions *vers;
506 struct vers_iter iter_info;
509 * Loop through all the devices working out how much
512 dm_target_iterate(list_version_get_needed, &needed);
515 * Grab our output buffer.
517 vers = get_result_buffer(param, param_size, &len);
519 param->flags |= DM_BUFFER_FULL_FLAG;
522 param->data_size = param->data_start + needed;
524 iter_info.param_size = param_size;
525 iter_info.old_vers = NULL;
526 iter_info.vers = vers;
528 iter_info.end = (char *)vers+len;
531 * Now loop through filling out the names & versions.
533 dm_target_iterate(list_version_get_info, &iter_info);
534 param->flags |= iter_info.flags;
542 static int check_name(const char *name)
544 if (strchr(name, '/')) {
545 DMWARN("invalid device name");
553 * Fills in a dm_ioctl structure, ready for sending back to
556 static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
558 struct gendisk *disk = dm_disk(md);
559 struct dm_table *table;
561 param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
562 DM_ACTIVE_PRESENT_FLAG);
564 if (dm_suspended(md))
565 param->flags |= DM_SUSPEND_FLAG;
567 param->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
570 * Yes, this will be out of date by the time it gets back
571 * to userland, but it is still very useful for
574 param->open_count = dm_open_count(md);
577 param->flags |= DM_READONLY_FLAG;
579 param->event_nr = dm_get_event_nr(md);
581 table = dm_get_table(md);
583 param->flags |= DM_ACTIVE_PRESENT_FLAG;
584 param->target_count = dm_table_get_num_targets(table);
587 param->target_count = 0;
592 static int dev_create(struct dm_ioctl *param, size_t param_size)
594 int r, m = DM_ANY_MINOR;
595 struct mapped_device *md;
597 r = check_name(param->name);
601 if (param->flags & DM_PERSISTENT_DEV_FLAG)
602 m = MINOR(huge_decode_dev(param->dev));
604 r = dm_create(m, &md);
608 r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
614 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
616 r = __dev_status(md, param);
623 * Always use UUID for lookups if it's present, otherwise use name or dev.
625 static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
627 struct mapped_device *md;
631 return __get_uuid_cell(param->uuid);
634 return __get_name_cell(param->name);
636 md = dm_get_md(huge_decode_dev(param->dev));
638 mdptr = dm_get_mdptr(md);
643 static struct mapped_device *find_device(struct dm_ioctl *param)
645 struct hash_cell *hc;
646 struct mapped_device *md = NULL;
648 down_read(&_hash_lock);
649 hc = __find_device_hash_cell(param);
654 * Sneakily write in both the name and the uuid
655 * while we have the cell.
657 strncpy(param->name, hc->name, sizeof(param->name));
659 strncpy(param->uuid, hc->uuid, sizeof(param->uuid)-1);
661 param->uuid[0] = '\0';
664 param->flags |= DM_INACTIVE_PRESENT_FLAG;
666 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
668 up_read(&_hash_lock);
673 static int dev_remove(struct dm_ioctl *param, size_t param_size)
675 struct hash_cell *hc;
676 struct mapped_device *md;
679 down_write(&_hash_lock);
680 hc = __find_device_hash_cell(param);
683 DMWARN("device doesn't appear to be in the dev hash table.");
684 up_write(&_hash_lock);
691 * Ensure the device is not open and nothing further can open it.
693 r = dm_lock_for_deletion(md);
695 DMWARN("unable to remove open device %s", hc->name);
696 up_write(&_hash_lock);
702 up_write(&_hash_lock);
704 param->data_size = 0;
709 * Check a string doesn't overrun the chunk of
710 * memory we copied from userland.
712 static int invalid_str(char *str, void *end)
714 while ((void *) str < end)
721 static int dev_rename(struct dm_ioctl *param, size_t param_size)
724 char *new_name = (char *) param + param->data_start;
726 if (new_name < (char *) (param + 1) ||
727 invalid_str(new_name, (void *) param + param_size)) {
728 DMWARN("Invalid new logical volume name supplied.");
732 r = check_name(new_name);
736 param->data_size = 0;
737 return dm_hash_rename(param->name, new_name);
740 static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
743 struct mapped_device *md;
744 struct hd_geometry geometry;
745 unsigned long indata[4];
746 char *geostr = (char *) param + param->data_start;
748 md = find_device(param);
752 if (geostr < (char *) (param + 1) ||
753 invalid_str(geostr, (void *) param + param_size)) {
754 DMWARN("Invalid geometry supplied.");
758 x = sscanf(geostr, "%lu %lu %lu %lu", indata,
759 indata + 1, indata + 2, indata + 3);
762 DMWARN("Unable to interpret geometry settings.");
766 if (indata[0] > 65535 || indata[1] > 255 ||
767 indata[2] > 255 || indata[3] > ULONG_MAX) {
768 DMWARN("Geometry exceeds range limits.");
772 geometry.cylinders = indata[0];
773 geometry.heads = indata[1];
774 geometry.sectors = indata[2];
775 geometry.start = indata[3];
777 r = dm_set_geometry(md, &geometry);
779 r = __dev_status(md, param);
781 param->data_size = 0;
788 static int do_suspend(struct dm_ioctl *param)
792 struct mapped_device *md;
794 md = find_device(param);
798 if (param->flags & DM_SKIP_LOCKFS_FLAG)
801 if (!dm_suspended(md))
802 r = dm_suspend(md, do_lockfs);
805 r = __dev_status(md, param);
811 static int do_resume(struct dm_ioctl *param)
815 struct hash_cell *hc;
816 struct mapped_device *md;
817 struct dm_table *new_map;
819 down_write(&_hash_lock);
821 hc = __find_device_hash_cell(param);
823 DMWARN("device doesn't appear to be in the dev hash table.");
824 up_write(&_hash_lock);
830 new_map = hc->new_map;
832 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
834 up_write(&_hash_lock);
836 /* Do we need to load a new map ? */
838 /* Suspend if it isn't already suspended */
839 if (param->flags & DM_SKIP_LOCKFS_FLAG)
841 if (!dm_suspended(md))
842 dm_suspend(md, do_lockfs);
844 r = dm_swap_table(md, new_map);
847 dm_table_put(new_map);
851 if (dm_table_get_mode(new_map) & FMODE_WRITE)
852 set_disk_ro(dm_disk(md), 0);
854 set_disk_ro(dm_disk(md), 1);
856 dm_table_put(new_map);
859 if (dm_suspended(md))
863 r = __dev_status(md, param);
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.
873 static int dev_suspend(struct dm_ioctl *param, size_t param_size)
875 if (param->flags & DM_SUSPEND_FLAG)
876 return do_suspend(param);
878 return do_resume(param);
882 * Copies device info back to user space, used by
883 * the create and info ioctls.
885 static int dev_status(struct dm_ioctl *param, size_t param_size)
888 struct mapped_device *md;
890 md = find_device(param);
894 r = __dev_status(md, param);
900 * Build up the status struct for each target
902 static void retrieve_status(struct dm_table *table,
903 struct dm_ioctl *param, size_t param_size)
905 unsigned int i, num_targets;
906 struct dm_target_spec *spec;
907 char *outbuf, *outptr;
909 size_t remaining, len, used = 0;
911 outptr = outbuf = get_result_buffer(param, param_size, &len);
913 if (param->flags & DM_STATUS_TABLE_FLAG)
914 type = STATUSTYPE_TABLE;
916 type = STATUSTYPE_INFO;
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);
923 remaining = len - (outptr - outbuf);
924 if (remaining <= sizeof(struct dm_target_spec)) {
925 param->flags |= DM_BUFFER_FULL_FLAG;
929 spec = (struct dm_target_spec *) outptr;
932 spec->sector_start = ti->begin;
933 spec->length = ti->len;
934 strncpy(spec->target_type, ti->type->name,
935 sizeof(spec->target_type));
937 outptr += sizeof(struct dm_target_spec);
938 remaining = len - (outptr - outbuf);
939 if (remaining <= 0) {
940 param->flags |= DM_BUFFER_FULL_FLAG;
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;
953 outptr += strlen(outptr) + 1;
954 used = param->data_start + (outptr - outbuf);
956 outptr = align_ptr(outptr);
957 spec->next = outptr - outbuf;
961 param->data_size = used;
963 param->target_count = num_targets;
967 * Wait for a device to report an event
969 static int dev_wait(struct dm_ioctl *param, size_t param_size)
972 struct mapped_device *md;
973 struct dm_table *table;
975 md = find_device(param);
980 * Wait for a notification event
982 if (dm_wait_event(md, param->event_nr)) {
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.
992 r = __dev_status(md, param);
996 table = dm_get_table(md);
998 retrieve_status(table, param, param_size);
1007 static inline int get_mode(struct dm_ioctl *param)
1009 int mode = FMODE_READ | FMODE_WRITE;
1011 if (param->flags & DM_READONLY_FLAG)
1017 static int next_target(struct dm_target_spec *last, uint32_t next, void *end,
1018 struct dm_target_spec **spec, char **target_params)
1020 *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
1021 *target_params = (char *) (*spec + 1);
1023 if (*spec < (last + 1))
1026 return invalid_str(*target_params, end);
1029 static int populate_table(struct dm_table *table,
1030 struct dm_ioctl *param, size_t param_size)
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;
1039 if (!param->target_count) {
1040 DMWARN("populate_table: no targets specified");
1044 for (i = 0; i < param->target_count; i++) {
1046 r = next_target(spec, next, end, &spec, &target_params);
1048 DMWARN("unable to find target");
1052 r = dm_table_add_target(table, spec->target_type,
1053 (sector_t) spec->sector_start,
1054 (sector_t) spec->length,
1057 DMWARN("error adding target to table");
1064 return dm_table_complete(table);
1067 static int table_load(struct dm_ioctl *param, size_t param_size)
1070 struct hash_cell *hc;
1072 struct mapped_device *md;
1074 md = find_device(param);
1078 r = dm_table_create(&t, get_mode(param), param->target_count, md);
1082 r = populate_table(t, param, param_size);
1088 down_write(&_hash_lock);
1089 hc = dm_get_mdptr(md);
1090 if (!hc || hc->md != md) {
1091 DMWARN("device has been removed from the dev hash table.");
1093 up_write(&_hash_lock);
1099 dm_table_put(hc->new_map);
1101 up_write(&_hash_lock);
1103 param->flags |= DM_INACTIVE_PRESENT_FLAG;
1104 r = __dev_status(md, param);
1112 static int table_clear(struct dm_ioctl *param, size_t param_size)
1115 struct hash_cell *hc;
1116 struct mapped_device *md;
1118 down_write(&_hash_lock);
1120 hc = __find_device_hash_cell(param);
1122 DMWARN("device doesn't appear to be in the dev hash table.");
1123 up_write(&_hash_lock);
1128 dm_table_put(hc->new_map);
1132 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1134 r = __dev_status(hc->md, param);
1136 up_write(&_hash_lock);
1142 * Retrieves a list of devices used by a particular dm device.
1144 static void retrieve_deps(struct dm_table *table,
1145 struct dm_ioctl *param, size_t param_size)
1147 unsigned int count = 0;
1148 struct list_head *tmp;
1151 struct dm_target_deps *deps;
1153 deps = get_result_buffer(param, param_size, &len);
1156 * Count the devices.
1158 list_for_each (tmp, dm_table_get_devices(table))
1162 * Check we have enough space.
1164 needed = sizeof(*deps) + (sizeof(*deps->dev) * count);
1166 param->flags |= DM_BUFFER_FULL_FLAG;
1171 * Fill in the devices.
1173 deps->count = count;
1175 list_for_each_entry (dd, dm_table_get_devices(table), list)
1176 deps->dev[count++] = huge_encode_dev(dd->bdev->bd_dev);
1178 param->data_size = param->data_start + needed;
1181 static int table_deps(struct dm_ioctl *param, size_t param_size)
1184 struct mapped_device *md;
1185 struct dm_table *table;
1187 md = find_device(param);
1191 r = __dev_status(md, param);
1195 table = dm_get_table(md);
1197 retrieve_deps(table, param, param_size);
1198 dm_table_put(table);
1207 * Return the status of a device as a text string for each
1210 static int table_status(struct dm_ioctl *param, size_t param_size)
1213 struct mapped_device *md;
1214 struct dm_table *table;
1216 md = find_device(param);
1220 r = __dev_status(md, param);
1224 table = dm_get_table(md);
1226 retrieve_status(table, param, param_size);
1227 dm_table_put(table);
1236 * Pass a message to the target that's at the supplied device offset.
1238 static int target_message(struct dm_ioctl *param, size_t param_size)
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;
1247 md = find_device(param);
1251 r = __dev_status(md, param);
1255 if (tmsg < (struct dm_target_msg *) (param + 1) ||
1256 invalid_str(tmsg->message, (void *) param + param_size)) {
1257 DMWARN("Invalid target message parameters.");
1262 r = dm_split_args(&argc, &argv, tmsg->message);
1264 DMWARN("Failed to split target message parameters");
1268 table = dm_get_table(md);
1272 if (tmsg->sector >= dm_table_get_size(table)) {
1273 DMWARN("Target message sector outside device.");
1278 ti = dm_table_find_target(table, tmsg->sector);
1279 if (ti->type->message)
1280 r = ti->type->message(ti, argc, argv);
1282 DMWARN("Target type does not support messages");
1287 dm_table_put(table);
1291 param->data_size = 0;
1296 /*-----------------------------------------------------------------
1297 * Implementation of open/close/ioctl on the special char
1299 *---------------------------------------------------------------*/
1300 static ioctl_fn lookup_ioctl(unsigned int cmd)
1306 {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */
1307 {DM_REMOVE_ALL_CMD, remove_all},
1308 {DM_LIST_DEVICES_CMD, list_devices},
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},
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},
1322 {DM_LIST_VERSIONS_CMD, list_versions},
1324 {DM_TARGET_MSG_CMD, target_message},
1325 {DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry}
1328 return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn;
1332 * As well as checking the version compatibility this always
1333 * copies the kernel interface version out.
1335 static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
1337 uint32_t version[3];
1340 if (copy_from_user(version, user->version, sizeof(version)))
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);
1354 * Fill in the kernel version.
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)))
1365 static void free_params(struct dm_ioctl *param)
1370 static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
1372 struct dm_ioctl tmp, *dmi;
1374 if (copy_from_user(&tmp, user, sizeof(tmp)))
1377 if (tmp.data_size < sizeof(tmp))
1380 dmi = (struct dm_ioctl *) vmalloc(tmp.data_size);
1384 if (copy_from_user(dmi, user, tmp.data_size)) {
1393 static int validate_params(uint cmd, struct dm_ioctl *param)
1395 /* Always clear this flag */
1396 param->flags &= ~DM_BUFFER_FULL_FLAG;
1398 /* Ignores parameters */
1399 if (cmd == DM_REMOVE_ALL_CMD ||
1400 cmd == DM_LIST_DEVICES_CMD ||
1401 cmd == DM_LIST_VERSIONS_CMD)
1404 if ((cmd == DM_DEV_CREATE_CMD)) {
1405 if (!*param->name) {
1406 DMWARN("name not supplied when creating device");
1409 } else if ((*param->uuid && *param->name)) {
1410 DMWARN("only supply one of name or uuid, cmd(%u)", cmd);
1414 /* Ensure strings are terminated */
1415 param->name[DM_NAME_LEN - 1] = '\0';
1416 param->uuid[DM_UUID_LEN - 1] = '\0';
1421 static int ctl_ioctl(struct inode *inode, struct file *file,
1422 uint command, ulong u)
1426 struct dm_ioctl *param;
1427 struct dm_ioctl __user *user = (struct dm_ioctl __user *) u;
1431 /* only root can play with this */
1432 if (!capable(CAP_SYS_ADMIN))
1435 if (_IOC_TYPE(command) != DM_IOCTL)
1438 cmd = _IOC_NR(command);
1441 * Check the interface version passed in. This also
1442 * writes out the kernel's interface version.
1444 r = check_version(cmd, user);
1449 * Nothing more to do for the version command.
1451 if (cmd == DM_VERSION_CMD)
1454 fn = lookup_ioctl(cmd);
1456 DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
1461 * Trying to avoid low memory issues when a device is
1464 current->flags |= PF_MEMALLOC;
1467 * Copy the parameters into kernel space.
1469 r = copy_params(user, ¶m);
1471 current->flags &= ~PF_MEMALLOC;
1476 r = validate_params(cmd, param);
1480 param_size = param->data_size;
1481 param->data_size = sizeof(*param);
1482 r = fn(param, param_size);
1485 * Copy the results back to userland.
1487 if (!r && copy_to_user(user, param, param->data_size))
1495 static struct file_operations _ctl_fops = {
1497 .owner = THIS_MODULE,
1500 static struct miscdevice _dm_misc = {
1501 .minor = MISC_DYNAMIC_MINOR,
1503 .devfs_name = "mapper/control",
1508 * Create misc character device and link to DM_DIR/control.
1510 int __init dm_interface_init(void)
1518 r = misc_register(&_dm_misc);
1520 DMERR("misc_register failed for control device");
1525 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
1526 DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
1531 void dm_interface_exit(void)
1533 if (misc_deregister(&_dm_misc) < 0)
1534 DMERR("misc_deregister failed for control device");