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);
79 /*-----------------------------------------------------------------
81 * We're not really concerned with the str hash function being
82 * fast since it's only used by the ioctl interface.
83 *---------------------------------------------------------------*/
84 static unsigned int hash_str(const char *str)
86 const unsigned int hash_mult = 2654435387U;
90 h = (h + (unsigned int) *str++) * hash_mult;
92 return h & MASK_BUCKETS;
95 /*-----------------------------------------------------------------
96 * Code for looking up a device by name
97 *---------------------------------------------------------------*/
98 static struct hash_cell *__get_name_cell(const char *str)
100 struct hash_cell *hc;
101 unsigned int h = hash_str(str);
103 list_for_each_entry (hc, _name_buckets + h, name_list)
104 if (!strcmp(hc->name, str)) {
112 static struct hash_cell *__get_uuid_cell(const char *str)
114 struct hash_cell *hc;
115 unsigned int h = hash_str(str);
117 list_for_each_entry (hc, _uuid_buckets + h, uuid_list)
118 if (!strcmp(hc->uuid, str)) {
126 /*-----------------------------------------------------------------
127 * Inserting, removing and renaming a device.
128 *---------------------------------------------------------------*/
129 static struct hash_cell *alloc_cell(const char *name, const char *uuid,
130 struct mapped_device *md)
132 struct hash_cell *hc;
134 hc = kmalloc(sizeof(*hc), GFP_KERNEL);
138 hc->name = kstrdup(name, GFP_KERNEL);
148 hc->uuid = kstrdup(uuid, GFP_KERNEL);
156 INIT_LIST_HEAD(&hc->name_list);
157 INIT_LIST_HEAD(&hc->uuid_list);
163 static void free_cell(struct hash_cell *hc)
173 * The kdev_t and uuid of a device can never change once it is
174 * initially inserted.
176 static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
178 struct hash_cell *cell, *hc;
181 * Allocate the new cells.
183 cell = alloc_cell(name, uuid, md);
188 * Insert the cell into both hash tables.
190 down_write(&_hash_lock);
191 hc = __get_name_cell(name);
197 list_add(&cell->name_list, _name_buckets + hash_str(name));
200 hc = __get_uuid_cell(uuid);
202 list_del(&cell->name_list);
206 list_add(&cell->uuid_list, _uuid_buckets + hash_str(uuid));
209 dm_set_mdptr(md, cell);
210 up_write(&_hash_lock);
215 up_write(&_hash_lock);
220 static void __hash_remove(struct hash_cell *hc)
222 struct dm_table *table;
224 /* remove from the dev hash */
225 list_del(&hc->uuid_list);
226 list_del(&hc->name_list);
227 dm_set_mdptr(hc->md, NULL);
229 table = dm_get_table(hc->md);
231 dm_table_event(table);
236 dm_table_put(hc->new_map);
241 static void dm_hash_remove_all(int keep_open_devices)
243 int i, dev_skipped, dev_removed;
244 struct hash_cell *hc;
245 struct list_head *tmp, *n;
247 down_write(&_hash_lock);
250 dev_skipped = dev_removed = 0;
251 for (i = 0; i < NUM_BUCKETS; i++) {
252 list_for_each_safe (tmp, n, _name_buckets + i) {
253 hc = list_entry(tmp, struct hash_cell, name_list);
255 if (keep_open_devices &&
256 dm_lock_for_deletion(hc->md)) {
266 * Some mapped devices may be using other mapped devices, so if any
267 * still exist, repeat until we make no further progress.
273 DMWARN("remove_all left %d open device(s)", dev_skipped);
276 up_write(&_hash_lock);
279 static int dm_hash_rename(const char *old, const char *new)
281 char *new_name, *old_name;
282 struct hash_cell *hc;
283 struct dm_table *table;
288 new_name = kstrdup(new, GFP_KERNEL);
292 down_write(&_hash_lock);
297 hc = __get_name_cell(new);
299 DMWARN("asked to rename to an already existing name %s -> %s",
302 up_write(&_hash_lock);
308 * Is there such a device as 'old' ?
310 hc = __get_name_cell(old);
312 DMWARN("asked to rename a non existent device %s -> %s",
314 up_write(&_hash_lock);
320 * rename and move the name cell.
322 list_del(&hc->name_list);
325 list_add(&hc->name_list, _name_buckets + hash_str(new_name));
328 * Wake up any dm event waiters.
330 table = dm_get_table(hc->md);
332 dm_table_event(table);
337 up_write(&_hash_lock);
342 /*-----------------------------------------------------------------
343 * Implementation of the ioctl commands
344 *---------------------------------------------------------------*/
346 * All the ioctl commands get dispatched to functions with this
349 typedef int (*ioctl_fn)(struct dm_ioctl *param, size_t param_size);
351 static int remove_all(struct dm_ioctl *param, size_t param_size)
353 dm_hash_remove_all(1);
354 param->data_size = 0;
359 * Round up the ptr to an 8-byte boundary.
362 static inline void *align_ptr(void *ptr)
364 return (void *) (((size_t) (ptr + ALIGN_MASK)) & ~ALIGN_MASK);
368 * Retrieves the data payload buffer from an already allocated
371 static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
374 param->data_start = align_ptr(param + 1) - (void *) param;
376 if (param->data_start < param_size)
377 *len = param_size - param->data_start;
381 return ((void *) param) + param->data_start;
384 static int list_devices(struct dm_ioctl *param, size_t param_size)
387 struct hash_cell *hc;
388 size_t len, needed = 0;
389 struct gendisk *disk;
390 struct dm_name_list *nl, *old_nl = NULL;
392 down_write(&_hash_lock);
395 * Loop through all the devices working out how much
398 for (i = 0; i < NUM_BUCKETS; i++) {
399 list_for_each_entry (hc, _name_buckets + i, name_list) {
400 needed += sizeof(struct dm_name_list);
401 needed += strlen(hc->name) + 1;
402 needed += ALIGN_MASK;
407 * Grab our output buffer.
409 nl = get_result_buffer(param, param_size, &len);
411 param->flags |= DM_BUFFER_FULL_FLAG;
414 param->data_size = param->data_start + needed;
416 nl->dev = 0; /* Flags no data */
419 * Now loop through filling out the names.
421 for (i = 0; i < NUM_BUCKETS; i++) {
422 list_for_each_entry (hc, _name_buckets + i, name_list) {
424 old_nl->next = (uint32_t) ((void *) nl -
426 disk = dm_disk(hc->md);
427 nl->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
429 strcpy(nl->name, hc->name);
432 nl = align_ptr(((void *) ++nl) + strlen(hc->name) + 1);
437 up_write(&_hash_lock);
441 static void list_version_get_needed(struct target_type *tt, void *needed_param)
443 size_t *needed = needed_param;
445 *needed += sizeof(struct dm_target_versions);
446 *needed += strlen(tt->name);
447 *needed += ALIGN_MASK;
450 static void list_version_get_info(struct target_type *tt, void *param)
452 struct vers_iter *info = param;
454 /* Check space - it might have changed since the first iteration */
455 if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 >
458 info->flags = DM_BUFFER_FULL_FLAG;
463 info->old_vers->next = (uint32_t) ((void *)info->vers -
464 (void *)info->old_vers);
465 info->vers->version[0] = tt->version[0];
466 info->vers->version[1] = tt->version[1];
467 info->vers->version[2] = tt->version[2];
468 info->vers->next = 0;
469 strcpy(info->vers->name, tt->name);
471 info->old_vers = info->vers;
472 info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
475 static int list_versions(struct dm_ioctl *param, size_t param_size)
477 size_t len, needed = 0;
478 struct dm_target_versions *vers;
479 struct vers_iter iter_info;
482 * Loop through all the devices working out how much
485 dm_target_iterate(list_version_get_needed, &needed);
488 * Grab our output buffer.
490 vers = get_result_buffer(param, param_size, &len);
492 param->flags |= DM_BUFFER_FULL_FLAG;
495 param->data_size = param->data_start + needed;
497 iter_info.param_size = param_size;
498 iter_info.old_vers = NULL;
499 iter_info.vers = vers;
501 iter_info.end = (char *)vers+len;
504 * Now loop through filling out the names & versions.
506 dm_target_iterate(list_version_get_info, &iter_info);
507 param->flags |= iter_info.flags;
515 static int check_name(const char *name)
517 if (strchr(name, '/')) {
518 DMWARN("invalid device name");
526 * Fills in a dm_ioctl structure, ready for sending back to
529 static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
531 struct gendisk *disk = dm_disk(md);
532 struct dm_table *table;
534 param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
535 DM_ACTIVE_PRESENT_FLAG);
537 if (dm_suspended(md))
538 param->flags |= DM_SUSPEND_FLAG;
540 param->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
543 * Yes, this will be out of date by the time it gets back
544 * to userland, but it is still very useful for
547 param->open_count = dm_open_count(md);
550 param->flags |= DM_READONLY_FLAG;
552 param->event_nr = dm_get_event_nr(md);
554 table = dm_get_table(md);
556 param->flags |= DM_ACTIVE_PRESENT_FLAG;
557 param->target_count = dm_table_get_num_targets(table);
560 param->target_count = 0;
565 static int dev_create(struct dm_ioctl *param, size_t param_size)
567 int r, m = DM_ANY_MINOR;
568 struct mapped_device *md;
570 r = check_name(param->name);
574 if (param->flags & DM_PERSISTENT_DEV_FLAG)
575 m = MINOR(huge_decode_dev(param->dev));
577 r = dm_create(m, &md);
581 r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
587 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
589 r = __dev_status(md, param);
596 * Always use UUID for lookups if it's present, otherwise use name or dev.
598 static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
600 struct mapped_device *md;
604 return __get_uuid_cell(param->uuid);
607 return __get_name_cell(param->name);
609 md = dm_get_md(huge_decode_dev(param->dev));
611 mdptr = dm_get_mdptr(md);
616 static struct mapped_device *find_device(struct dm_ioctl *param)
618 struct hash_cell *hc;
619 struct mapped_device *md = NULL;
621 down_read(&_hash_lock);
622 hc = __find_device_hash_cell(param);
627 * Sneakily write in both the name and the uuid
628 * while we have the cell.
630 strncpy(param->name, hc->name, sizeof(param->name));
632 strncpy(param->uuid, hc->uuid, sizeof(param->uuid)-1);
634 param->uuid[0] = '\0';
637 param->flags |= DM_INACTIVE_PRESENT_FLAG;
639 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
641 up_read(&_hash_lock);
646 static int dev_remove(struct dm_ioctl *param, size_t param_size)
648 struct hash_cell *hc;
649 struct mapped_device *md;
652 down_write(&_hash_lock);
653 hc = __find_device_hash_cell(param);
656 DMWARN("device doesn't appear to be in the dev hash table.");
657 up_write(&_hash_lock);
664 * Ensure the device is not open and nothing further can open it.
666 r = dm_lock_for_deletion(md);
668 DMWARN("unable to remove open device %s", hc->name);
669 up_write(&_hash_lock);
675 up_write(&_hash_lock);
677 param->data_size = 0;
682 * Check a string doesn't overrun the chunk of
683 * memory we copied from userland.
685 static int invalid_str(char *str, void *end)
687 while ((void *) str < end)
694 static int dev_rename(struct dm_ioctl *param, size_t param_size)
697 char *new_name = (char *) param + param->data_start;
699 if (new_name < (char *) (param + 1) ||
700 invalid_str(new_name, (void *) param + param_size)) {
701 DMWARN("Invalid new logical volume name supplied.");
705 r = check_name(new_name);
709 param->data_size = 0;
710 return dm_hash_rename(param->name, new_name);
713 static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
716 struct mapped_device *md;
717 struct hd_geometry geometry;
718 unsigned long indata[4];
719 char *geostr = (char *) param + param->data_start;
721 md = find_device(param);
725 if (geostr < (char *) (param + 1) ||
726 invalid_str(geostr, (void *) param + param_size)) {
727 DMWARN("Invalid geometry supplied.");
731 x = sscanf(geostr, "%lu %lu %lu %lu", indata,
732 indata + 1, indata + 2, indata + 3);
735 DMWARN("Unable to interpret geometry settings.");
739 if (indata[0] > 65535 || indata[1] > 255 ||
740 indata[2] > 255 || indata[3] > ULONG_MAX) {
741 DMWARN("Geometry exceeds range limits.");
745 geometry.cylinders = indata[0];
746 geometry.heads = indata[1];
747 geometry.sectors = indata[2];
748 geometry.start = indata[3];
750 r = dm_set_geometry(md, &geometry);
752 r = __dev_status(md, param);
754 param->data_size = 0;
761 static int do_suspend(struct dm_ioctl *param)
765 struct mapped_device *md;
767 md = find_device(param);
771 if (param->flags & DM_SKIP_LOCKFS_FLAG)
774 if (!dm_suspended(md))
775 r = dm_suspend(md, do_lockfs);
778 r = __dev_status(md, param);
784 static int do_resume(struct dm_ioctl *param)
788 struct hash_cell *hc;
789 struct mapped_device *md;
790 struct dm_table *new_map;
792 down_write(&_hash_lock);
794 hc = __find_device_hash_cell(param);
796 DMWARN("device doesn't appear to be in the dev hash table.");
797 up_write(&_hash_lock);
803 new_map = hc->new_map;
805 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
807 up_write(&_hash_lock);
809 /* Do we need to load a new map ? */
811 /* Suspend if it isn't already suspended */
812 if (param->flags & DM_SKIP_LOCKFS_FLAG)
814 if (!dm_suspended(md))
815 dm_suspend(md, do_lockfs);
817 r = dm_swap_table(md, new_map);
820 dm_table_put(new_map);
824 if (dm_table_get_mode(new_map) & FMODE_WRITE)
825 set_disk_ro(dm_disk(md), 0);
827 set_disk_ro(dm_disk(md), 1);
829 dm_table_put(new_map);
832 if (dm_suspended(md))
836 r = __dev_status(md, param);
843 * Set or unset the suspension state of a device.
844 * If the device already is in the requested state we just return its status.
846 static int dev_suspend(struct dm_ioctl *param, size_t param_size)
848 if (param->flags & DM_SUSPEND_FLAG)
849 return do_suspend(param);
851 return do_resume(param);
855 * Copies device info back to user space, used by
856 * the create and info ioctls.
858 static int dev_status(struct dm_ioctl *param, size_t param_size)
861 struct mapped_device *md;
863 md = find_device(param);
867 r = __dev_status(md, param);
873 * Build up the status struct for each target
875 static void retrieve_status(struct dm_table *table,
876 struct dm_ioctl *param, size_t param_size)
878 unsigned int i, num_targets;
879 struct dm_target_spec *spec;
880 char *outbuf, *outptr;
882 size_t remaining, len, used = 0;
884 outptr = outbuf = get_result_buffer(param, param_size, &len);
886 if (param->flags & DM_STATUS_TABLE_FLAG)
887 type = STATUSTYPE_TABLE;
889 type = STATUSTYPE_INFO;
891 /* Get all the target info */
892 num_targets = dm_table_get_num_targets(table);
893 for (i = 0; i < num_targets; i++) {
894 struct dm_target *ti = dm_table_get_target(table, i);
896 remaining = len - (outptr - outbuf);
897 if (remaining <= sizeof(struct dm_target_spec)) {
898 param->flags |= DM_BUFFER_FULL_FLAG;
902 spec = (struct dm_target_spec *) outptr;
905 spec->sector_start = ti->begin;
906 spec->length = ti->len;
907 strncpy(spec->target_type, ti->type->name,
908 sizeof(spec->target_type));
910 outptr += sizeof(struct dm_target_spec);
911 remaining = len - (outptr - outbuf);
912 if (remaining <= 0) {
913 param->flags |= DM_BUFFER_FULL_FLAG;
917 /* Get the status/table string from the target driver */
918 if (ti->type->status) {
919 if (ti->type->status(ti, type, outptr, remaining)) {
920 param->flags |= DM_BUFFER_FULL_FLAG;
926 outptr += strlen(outptr) + 1;
927 used = param->data_start + (outptr - outbuf);
929 outptr = align_ptr(outptr);
930 spec->next = outptr - outbuf;
934 param->data_size = used;
936 param->target_count = num_targets;
940 * Wait for a device to report an event
942 static int dev_wait(struct dm_ioctl *param, size_t param_size)
945 struct mapped_device *md;
946 struct dm_table *table;
948 md = find_device(param);
953 * Wait for a notification event
955 if (dm_wait_event(md, param->event_nr)) {
961 * The userland program is going to want to know what
962 * changed to trigger the event, so we may as well tell
963 * him and save an ioctl.
965 r = __dev_status(md, param);
969 table = dm_get_table(md);
971 retrieve_status(table, param, param_size);
980 static inline int get_mode(struct dm_ioctl *param)
982 int mode = FMODE_READ | FMODE_WRITE;
984 if (param->flags & DM_READONLY_FLAG)
990 static int next_target(struct dm_target_spec *last, uint32_t next, void *end,
991 struct dm_target_spec **spec, char **target_params)
993 *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
994 *target_params = (char *) (*spec + 1);
996 if (*spec < (last + 1))
999 return invalid_str(*target_params, end);
1002 static int populate_table(struct dm_table *table,
1003 struct dm_ioctl *param, size_t param_size)
1007 struct dm_target_spec *spec = (struct dm_target_spec *) param;
1008 uint32_t next = param->data_start;
1009 void *end = (void *) param + param_size;
1010 char *target_params;
1012 if (!param->target_count) {
1013 DMWARN("populate_table: no targets specified");
1017 for (i = 0; i < param->target_count; i++) {
1019 r = next_target(spec, next, end, &spec, &target_params);
1021 DMWARN("unable to find target");
1025 r = dm_table_add_target(table, spec->target_type,
1026 (sector_t) spec->sector_start,
1027 (sector_t) spec->length,
1030 DMWARN("error adding target to table");
1037 return dm_table_complete(table);
1040 static int table_load(struct dm_ioctl *param, size_t param_size)
1043 struct hash_cell *hc;
1045 struct mapped_device *md;
1047 md = find_device(param);
1051 r = dm_table_create(&t, get_mode(param), param->target_count, md);
1055 r = populate_table(t, param, param_size);
1061 down_write(&_hash_lock);
1062 hc = dm_get_mdptr(md);
1063 if (!hc || hc->md != md) {
1064 DMWARN("device has been removed from the dev hash table.");
1066 up_write(&_hash_lock);
1072 dm_table_put(hc->new_map);
1074 up_write(&_hash_lock);
1076 param->flags |= DM_INACTIVE_PRESENT_FLAG;
1077 r = __dev_status(md, param);
1085 static int table_clear(struct dm_ioctl *param, size_t param_size)
1088 struct hash_cell *hc;
1089 struct mapped_device *md;
1091 down_write(&_hash_lock);
1093 hc = __find_device_hash_cell(param);
1095 DMWARN("device doesn't appear to be in the dev hash table.");
1096 up_write(&_hash_lock);
1101 dm_table_put(hc->new_map);
1105 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1107 r = __dev_status(hc->md, param);
1109 up_write(&_hash_lock);
1115 * Retrieves a list of devices used by a particular dm device.
1117 static void retrieve_deps(struct dm_table *table,
1118 struct dm_ioctl *param, size_t param_size)
1120 unsigned int count = 0;
1121 struct list_head *tmp;
1124 struct dm_target_deps *deps;
1126 deps = get_result_buffer(param, param_size, &len);
1129 * Count the devices.
1131 list_for_each (tmp, dm_table_get_devices(table))
1135 * Check we have enough space.
1137 needed = sizeof(*deps) + (sizeof(*deps->dev) * count);
1139 param->flags |= DM_BUFFER_FULL_FLAG;
1144 * Fill in the devices.
1146 deps->count = count;
1148 list_for_each_entry (dd, dm_table_get_devices(table), list)
1149 deps->dev[count++] = huge_encode_dev(dd->bdev->bd_dev);
1151 param->data_size = param->data_start + needed;
1154 static int table_deps(struct dm_ioctl *param, size_t param_size)
1157 struct mapped_device *md;
1158 struct dm_table *table;
1160 md = find_device(param);
1164 r = __dev_status(md, param);
1168 table = dm_get_table(md);
1170 retrieve_deps(table, param, param_size);
1171 dm_table_put(table);
1180 * Return the status of a device as a text string for each
1183 static int table_status(struct dm_ioctl *param, size_t param_size)
1186 struct mapped_device *md;
1187 struct dm_table *table;
1189 md = find_device(param);
1193 r = __dev_status(md, param);
1197 table = dm_get_table(md);
1199 retrieve_status(table, param, param_size);
1200 dm_table_put(table);
1209 * Pass a message to the target that's at the supplied device offset.
1211 static int target_message(struct dm_ioctl *param, size_t param_size)
1215 struct mapped_device *md;
1216 struct dm_table *table;
1217 struct dm_target *ti;
1218 struct dm_target_msg *tmsg = (void *) param + param->data_start;
1220 md = find_device(param);
1224 r = __dev_status(md, param);
1228 if (tmsg < (struct dm_target_msg *) (param + 1) ||
1229 invalid_str(tmsg->message, (void *) param + param_size)) {
1230 DMWARN("Invalid target message parameters.");
1235 r = dm_split_args(&argc, &argv, tmsg->message);
1237 DMWARN("Failed to split target message parameters");
1241 table = dm_get_table(md);
1245 if (tmsg->sector >= dm_table_get_size(table)) {
1246 DMWARN("Target message sector outside device.");
1251 ti = dm_table_find_target(table, tmsg->sector);
1252 if (ti->type->message)
1253 r = ti->type->message(ti, argc, argv);
1255 DMWARN("Target type does not support messages");
1260 dm_table_put(table);
1264 param->data_size = 0;
1269 /*-----------------------------------------------------------------
1270 * Implementation of open/close/ioctl on the special char
1272 *---------------------------------------------------------------*/
1273 static ioctl_fn lookup_ioctl(unsigned int cmd)
1279 {DM_VERSION_CMD, NULL}, /* version is dealt with elsewhere */
1280 {DM_REMOVE_ALL_CMD, remove_all},
1281 {DM_LIST_DEVICES_CMD, list_devices},
1283 {DM_DEV_CREATE_CMD, dev_create},
1284 {DM_DEV_REMOVE_CMD, dev_remove},
1285 {DM_DEV_RENAME_CMD, dev_rename},
1286 {DM_DEV_SUSPEND_CMD, dev_suspend},
1287 {DM_DEV_STATUS_CMD, dev_status},
1288 {DM_DEV_WAIT_CMD, dev_wait},
1290 {DM_TABLE_LOAD_CMD, table_load},
1291 {DM_TABLE_CLEAR_CMD, table_clear},
1292 {DM_TABLE_DEPS_CMD, table_deps},
1293 {DM_TABLE_STATUS_CMD, table_status},
1295 {DM_LIST_VERSIONS_CMD, list_versions},
1297 {DM_TARGET_MSG_CMD, target_message},
1298 {DM_DEV_SET_GEOMETRY_CMD, dev_set_geometry}
1301 return (cmd >= ARRAY_SIZE(_ioctls)) ? NULL : _ioctls[cmd].fn;
1305 * As well as checking the version compatibility this always
1306 * copies the kernel interface version out.
1308 static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
1310 uint32_t version[3];
1313 if (copy_from_user(version, user->version, sizeof(version)))
1316 if ((DM_VERSION_MAJOR != version[0]) ||
1317 (DM_VERSION_MINOR < version[1])) {
1318 DMWARN("ioctl interface mismatch: "
1319 "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1320 DM_VERSION_MAJOR, DM_VERSION_MINOR,
1321 DM_VERSION_PATCHLEVEL,
1322 version[0], version[1], version[2], cmd);
1327 * Fill in the kernel version.
1329 version[0] = DM_VERSION_MAJOR;
1330 version[1] = DM_VERSION_MINOR;
1331 version[2] = DM_VERSION_PATCHLEVEL;
1332 if (copy_to_user(user->version, version, sizeof(version)))
1338 static void free_params(struct dm_ioctl *param)
1343 static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
1345 struct dm_ioctl tmp, *dmi;
1347 if (copy_from_user(&tmp, user, sizeof(tmp)))
1350 if (tmp.data_size < sizeof(tmp))
1353 dmi = (struct dm_ioctl *) vmalloc(tmp.data_size);
1357 if (copy_from_user(dmi, user, tmp.data_size)) {
1366 static int validate_params(uint cmd, struct dm_ioctl *param)
1368 /* Always clear this flag */
1369 param->flags &= ~DM_BUFFER_FULL_FLAG;
1371 /* Ignores parameters */
1372 if (cmd == DM_REMOVE_ALL_CMD ||
1373 cmd == DM_LIST_DEVICES_CMD ||
1374 cmd == DM_LIST_VERSIONS_CMD)
1377 if ((cmd == DM_DEV_CREATE_CMD)) {
1378 if (!*param->name) {
1379 DMWARN("name not supplied when creating device");
1382 } else if ((*param->uuid && *param->name)) {
1383 DMWARN("only supply one of name or uuid, cmd(%u)", cmd);
1387 /* Ensure strings are terminated */
1388 param->name[DM_NAME_LEN - 1] = '\0';
1389 param->uuid[DM_UUID_LEN - 1] = '\0';
1394 static int ctl_ioctl(struct inode *inode, struct file *file,
1395 uint command, ulong u)
1399 struct dm_ioctl *param;
1400 struct dm_ioctl __user *user = (struct dm_ioctl __user *) u;
1404 /* only root can play with this */
1405 if (!capable(CAP_SYS_ADMIN))
1408 if (_IOC_TYPE(command) != DM_IOCTL)
1411 cmd = _IOC_NR(command);
1414 * Check the interface version passed in. This also
1415 * writes out the kernel's interface version.
1417 r = check_version(cmd, user);
1422 * Nothing more to do for the version command.
1424 if (cmd == DM_VERSION_CMD)
1427 fn = lookup_ioctl(cmd);
1429 DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
1434 * Trying to avoid low memory issues when a device is
1437 current->flags |= PF_MEMALLOC;
1440 * Copy the parameters into kernel space.
1442 r = copy_params(user, ¶m);
1444 current->flags &= ~PF_MEMALLOC;
1449 r = validate_params(cmd, param);
1453 param_size = param->data_size;
1454 param->data_size = sizeof(*param);
1455 r = fn(param, param_size);
1458 * Copy the results back to userland.
1460 if (!r && copy_to_user(user, param, param->data_size))
1468 static struct file_operations _ctl_fops = {
1470 .owner = THIS_MODULE,
1473 static struct miscdevice _dm_misc = {
1474 .minor = MISC_DYNAMIC_MINOR,
1476 .devfs_name = "mapper/control",
1481 * Create misc character device and link to DM_DIR/control.
1483 int __init dm_interface_init(void)
1491 r = misc_register(&_dm_misc);
1493 DMERR("misc_register failed for control device");
1498 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
1499 DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
1504 void dm_interface_exit(void)
1506 if (misc_deregister(&_dm_misc) < 0)
1507 DMERR("misc_deregister failed for control device");