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/sched/mm.h>
14 #include <linux/init.h>
15 #include <linux/wait.h>
16 #include <linux/slab.h>
17 #include <linux/rbtree.h>
18 #include <linux/dm-ioctl.h>
19 #include <linux/hdreg.h>
20 #include <linux/compat.h>
22 #include <linux/uaccess.h>
24 #define DM_MSG_PREFIX "ioctl"
25 #define DM_DRIVER_EMAIL "dm-devel@redhat.com"
29 * poll will wait until the global event number is greater than
32 volatile unsigned global_event_nr;
35 /*-----------------------------------------------------------------
36 * The ioctl interface needs to be able to look up devices by
38 *---------------------------------------------------------------*/
40 struct rb_node name_node;
41 struct rb_node uuid_node;
47 struct mapped_device *md;
48 struct dm_table *new_map;
53 struct dm_target_versions *vers, *old_vers;
59 static struct rb_root name_rb_tree = RB_ROOT;
60 static struct rb_root uuid_rb_tree = RB_ROOT;
62 static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred);
65 * Guards access to both hash tables.
67 static DECLARE_RWSEM(_hash_lock);
70 * Protects use of mdptr to obtain hash cell name and uuid from mapped device.
72 static DEFINE_MUTEX(dm_hash_cells_mutex);
74 static void dm_hash_exit(void)
76 dm_hash_remove_all(false, false, false);
79 /*-----------------------------------------------------------------
80 * Code for looking up a device by name
81 *---------------------------------------------------------------*/
82 static struct hash_cell *__get_name_cell(const char *str)
84 struct rb_node *n = name_rb_tree.rb_node;
87 struct hash_cell *hc = container_of(n, struct hash_cell, name_node);
88 int c = strcmp(hc->name, str);
93 n = c >= 0 ? n->rb_left : n->rb_right;
99 static struct hash_cell *__get_uuid_cell(const char *str)
101 struct rb_node *n = uuid_rb_tree.rb_node;
104 struct hash_cell *hc = container_of(n, struct hash_cell, uuid_node);
105 int c = strcmp(hc->uuid, str);
110 n = c >= 0 ? n->rb_left : n->rb_right;
116 static void __unlink_name(struct hash_cell *hc)
119 hc->name_set = false;
120 rb_erase(&hc->name_node, &name_rb_tree);
124 static void __unlink_uuid(struct hash_cell *hc)
127 hc->uuid_set = false;
128 rb_erase(&hc->uuid_node, &uuid_rb_tree);
132 static void __link_name(struct hash_cell *new_hc)
134 struct rb_node **n, *parent;
136 __unlink_name(new_hc);
138 new_hc->name_set = true;
140 n = &name_rb_tree.rb_node;
144 struct hash_cell *hc = container_of(*n, struct hash_cell, name_node);
145 int c = strcmp(hc->name, new_hc->name);
148 n = c >= 0 ? &hc->name_node.rb_left : &hc->name_node.rb_right;
151 rb_link_node(&new_hc->name_node, parent, n);
152 rb_insert_color(&new_hc->name_node, &name_rb_tree);
155 static void __link_uuid(struct hash_cell *new_hc)
157 struct rb_node **n, *parent;
159 __unlink_uuid(new_hc);
161 new_hc->uuid_set = true;
163 n = &uuid_rb_tree.rb_node;
167 struct hash_cell *hc = container_of(*n, struct hash_cell, uuid_node);
168 int c = strcmp(hc->uuid, new_hc->uuid);
171 n = c > 0 ? &hc->uuid_node.rb_left : &hc->uuid_node.rb_right;
174 rb_link_node(&new_hc->uuid_node, parent, n);
175 rb_insert_color(&new_hc->uuid_node, &uuid_rb_tree);
178 static struct hash_cell *__get_dev_cell(uint64_t dev)
180 struct mapped_device *md;
181 struct hash_cell *hc;
183 md = dm_get_md(huge_decode_dev(dev));
187 hc = dm_get_mdptr(md);
196 /*-----------------------------------------------------------------
197 * Inserting, removing and renaming a device.
198 *---------------------------------------------------------------*/
199 static struct hash_cell *alloc_cell(const char *name, const char *uuid,
200 struct mapped_device *md)
202 struct hash_cell *hc;
204 hc = kmalloc(sizeof(*hc), GFP_KERNEL);
208 hc->name = kstrdup(name, GFP_KERNEL);
218 hc->uuid = kstrdup(uuid, GFP_KERNEL);
226 hc->name_set = hc->uuid_set = false;
232 static void free_cell(struct hash_cell *hc)
242 * The kdev_t and uuid of a device can never change once it is
243 * initially inserted.
245 static int dm_hash_insert(const char *name, const char *uuid, struct mapped_device *md)
247 struct hash_cell *cell, *hc;
250 * Allocate the new cells.
252 cell = alloc_cell(name, uuid, md);
257 * Insert the cell into both hash tables.
259 down_write(&_hash_lock);
260 hc = __get_name_cell(name);
269 hc = __get_uuid_cell(uuid);
278 mutex_lock(&dm_hash_cells_mutex);
279 dm_set_mdptr(md, cell);
280 mutex_unlock(&dm_hash_cells_mutex);
281 up_write(&_hash_lock);
286 up_write(&_hash_lock);
291 static struct dm_table *__hash_remove(struct hash_cell *hc)
293 struct dm_table *table;
296 /* remove from the dev trees */
299 mutex_lock(&dm_hash_cells_mutex);
300 dm_set_mdptr(hc->md, NULL);
301 mutex_unlock(&dm_hash_cells_mutex);
303 table = dm_get_live_table(hc->md, &srcu_idx);
305 dm_table_event(table);
306 dm_put_live_table(hc->md, srcu_idx);
317 static void dm_hash_remove_all(bool keep_open_devices, bool mark_deferred, bool only_deferred)
321 struct hash_cell *hc;
322 struct mapped_device *md;
328 down_write(&_hash_lock);
330 for (n = rb_first(&name_rb_tree); n; n = rb_next(n)) {
331 hc = container_of(n, struct hash_cell, name_node);
335 if (keep_open_devices &&
336 dm_lock_for_deletion(md, mark_deferred, only_deferred)) {
342 t = __hash_remove(hc);
344 up_write(&_hash_lock);
351 if (likely(keep_open_devices))
354 dm_destroy_immediate(md);
357 * Some mapped devices may be using other mapped
358 * devices, so repeat until we make no further
359 * progress. If a new mapped device is created
360 * here it will also get removed.
365 up_write(&_hash_lock);
368 DMWARN("remove_all left %d open device(s)", dev_skipped);
372 * Set the uuid of a hash_cell that isn't already set.
374 static void __set_cell_uuid(struct hash_cell *hc, char *new_uuid)
376 mutex_lock(&dm_hash_cells_mutex);
378 mutex_unlock(&dm_hash_cells_mutex);
384 * Changes the name of a hash_cell and returns the old name for
385 * the caller to free.
387 static char *__change_cell_name(struct hash_cell *hc, char *new_name)
392 * Rename and move the name cell.
397 mutex_lock(&dm_hash_cells_mutex);
399 mutex_unlock(&dm_hash_cells_mutex);
406 static struct mapped_device *dm_hash_rename(struct dm_ioctl *param,
409 char *new_data, *old_name = NULL;
410 struct hash_cell *hc;
411 struct dm_table *table;
412 struct mapped_device *md;
413 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
419 new_data = kstrdup(new, GFP_KERNEL);
421 return ERR_PTR(-ENOMEM);
423 down_write(&_hash_lock);
429 hc = __get_uuid_cell(new);
431 hc = __get_name_cell(new);
434 DMWARN("Unable to change %s on mapped device %s to one that "
435 "already exists: %s",
436 change_uuid ? "uuid" : "name",
439 up_write(&_hash_lock);
441 return ERR_PTR(-EBUSY);
445 * Is there such a device as 'old' ?
447 hc = __get_name_cell(param->name);
449 DMWARN("Unable to rename non-existent device, %s to %s%s",
450 param->name, change_uuid ? "uuid " : "", new);
451 up_write(&_hash_lock);
453 return ERR_PTR(-ENXIO);
457 * Does this device already have a uuid?
459 if (change_uuid && hc->uuid) {
460 DMWARN("Unable to change uuid of mapped device %s to %s "
461 "because uuid is already set to %s",
462 param->name, new, hc->uuid);
464 up_write(&_hash_lock);
466 return ERR_PTR(-EINVAL);
470 __set_cell_uuid(hc, new_data);
472 old_name = __change_cell_name(hc, new_data);
475 * Wake up any dm event waiters.
477 table = dm_get_live_table(hc->md, &srcu_idx);
479 dm_table_event(table);
480 dm_put_live_table(hc->md, srcu_idx);
482 if (!dm_kobject_uevent(hc->md, KOBJ_CHANGE, param->event_nr))
483 param->flags |= DM_UEVENT_GENERATED_FLAG;
486 up_write(&_hash_lock);
492 void dm_deferred_remove(void)
494 dm_hash_remove_all(true, false, true);
497 /*-----------------------------------------------------------------
498 * Implementation of the ioctl commands
499 *---------------------------------------------------------------*/
501 * All the ioctl commands get dispatched to functions with this
504 typedef int (*ioctl_fn)(struct file *filp, struct dm_ioctl *param, size_t param_size);
506 static int remove_all(struct file *filp, struct dm_ioctl *param, size_t param_size)
508 dm_hash_remove_all(true, !!(param->flags & DM_DEFERRED_REMOVE), false);
509 param->data_size = 0;
514 * Round up the ptr to an 8-byte boundary.
517 static inline size_t align_val(size_t val)
519 return (val + ALIGN_MASK) & ~ALIGN_MASK;
521 static inline void *align_ptr(void *ptr)
523 return (void *)align_val((size_t)ptr);
527 * Retrieves the data payload buffer from an already allocated
530 static void *get_result_buffer(struct dm_ioctl *param, size_t param_size,
533 param->data_start = align_ptr(param + 1) - (void *) param;
535 if (param->data_start < param_size)
536 *len = param_size - param->data_start;
540 return ((void *) param) + param->data_start;
543 static bool filter_device(struct hash_cell *hc, const char *pfx_name, const char *pfx_uuid)
546 size_t val_len, pfx_len;
549 val_len = strlen(val);
550 pfx_len = strnlen(pfx_name, DM_NAME_LEN);
551 if (pfx_len > val_len)
553 if (memcmp(val, pfx_name, pfx_len))
556 val = hc->uuid ? hc->uuid : "";
557 val_len = strlen(val);
558 pfx_len = strnlen(pfx_uuid, DM_UUID_LEN);
559 if (pfx_len > val_len)
561 if (memcmp(val, pfx_uuid, pfx_len))
567 static int list_devices(struct file *filp, struct dm_ioctl *param, size_t param_size)
570 struct hash_cell *hc;
571 size_t len, needed = 0;
572 struct gendisk *disk;
573 struct dm_name_list *orig_nl, *nl, *old_nl = NULL;
576 down_write(&_hash_lock);
579 * Loop through all the devices working out how much
582 for (n = rb_first(&name_rb_tree); n; n = rb_next(n)) {
583 hc = container_of(n, struct hash_cell, name_node);
584 if (!filter_device(hc, param->name, param->uuid))
586 needed += align_val(offsetof(struct dm_name_list, name) + strlen(hc->name) + 1);
587 needed += align_val(sizeof(uint32_t) * 2);
588 if (param->flags & DM_UUID_FLAG && hc->uuid)
589 needed += align_val(strlen(hc->uuid) + 1);
593 * Grab our output buffer.
595 nl = orig_nl = get_result_buffer(param, param_size, &len);
596 if (len < needed || len < sizeof(nl->dev)) {
597 param->flags |= DM_BUFFER_FULL_FLAG;
600 param->data_size = param->data_start + needed;
602 nl->dev = 0; /* Flags no data */
605 * Now loop through filling out the names.
607 for (n = rb_first(&name_rb_tree); n; n = rb_next(n)) {
609 hc = container_of(n, struct hash_cell, name_node);
610 if (!filter_device(hc, param->name, param->uuid))
613 old_nl->next = (uint32_t) ((void *) nl -
615 disk = dm_disk(hc->md);
616 nl->dev = huge_encode_dev(disk_devt(disk));
618 strcpy(nl->name, hc->name);
621 event_nr = align_ptr(nl->name + strlen(hc->name) + 1);
622 event_nr[0] = dm_get_event_nr(hc->md);
624 uuid_ptr = align_ptr(event_nr + 2);
625 if (param->flags & DM_UUID_FLAG) {
627 event_nr[1] |= DM_NAME_LIST_FLAG_HAS_UUID;
628 strcpy(uuid_ptr, hc->uuid);
629 uuid_ptr = align_ptr(uuid_ptr + strlen(hc->uuid) + 1);
631 event_nr[1] |= DM_NAME_LIST_FLAG_DOESNT_HAVE_UUID;
637 * If mismatch happens, security may be compromised due to buffer
638 * overflow, so it's better to crash.
640 BUG_ON((char *)nl - (char *)orig_nl != needed);
643 up_write(&_hash_lock);
647 static void list_version_get_needed(struct target_type *tt, void *needed_param)
649 size_t *needed = needed_param;
651 *needed += sizeof(struct dm_target_versions);
652 *needed += strlen(tt->name);
653 *needed += ALIGN_MASK;
656 static void list_version_get_info(struct target_type *tt, void *param)
658 struct vers_iter *info = param;
660 /* Check space - it might have changed since the first iteration */
661 if ((char *)info->vers + sizeof(tt->version) + strlen(tt->name) + 1 >
664 info->flags = DM_BUFFER_FULL_FLAG;
669 info->old_vers->next = (uint32_t) ((void *)info->vers -
670 (void *)info->old_vers);
671 info->vers->version[0] = tt->version[0];
672 info->vers->version[1] = tt->version[1];
673 info->vers->version[2] = tt->version[2];
674 info->vers->next = 0;
675 strcpy(info->vers->name, tt->name);
677 info->old_vers = info->vers;
678 info->vers = align_ptr(((void *) ++info->vers) + strlen(tt->name) + 1);
681 static int __list_versions(struct dm_ioctl *param, size_t param_size, const char *name)
683 size_t len, needed = 0;
684 struct dm_target_versions *vers;
685 struct vers_iter iter_info;
686 struct target_type *tt = NULL;
689 tt = dm_get_target_type(name);
695 * Loop through all the devices working out how much
699 dm_target_iterate(list_version_get_needed, &needed);
701 list_version_get_needed(tt, &needed);
704 * Grab our output buffer.
706 vers = get_result_buffer(param, param_size, &len);
708 param->flags |= DM_BUFFER_FULL_FLAG;
711 param->data_size = param->data_start + needed;
713 iter_info.param_size = param_size;
714 iter_info.old_vers = NULL;
715 iter_info.vers = vers;
717 iter_info.end = (char *)vers+len;
720 * Now loop through filling out the names & versions.
723 dm_target_iterate(list_version_get_info, &iter_info);
725 list_version_get_info(tt, &iter_info);
726 param->flags |= iter_info.flags;
730 dm_put_target_type(tt);
734 static int list_versions(struct file *filp, struct dm_ioctl *param, size_t param_size)
736 return __list_versions(param, param_size, NULL);
739 static int get_target_version(struct file *filp, struct dm_ioctl *param, size_t param_size)
741 return __list_versions(param, param_size, param->name);
744 static int check_name(const char *name)
746 if (strchr(name, '/')) {
747 DMWARN("invalid device name");
755 * On successful return, the caller must not attempt to acquire
756 * _hash_lock without first calling dm_put_live_table, because dm_table_destroy
757 * waits for this dm_put_live_table and could be called under this lock.
759 static struct dm_table *dm_get_inactive_table(struct mapped_device *md, int *srcu_idx)
761 struct hash_cell *hc;
762 struct dm_table *table = NULL;
764 /* increment rcu count, we don't care about the table pointer */
765 dm_get_live_table(md, srcu_idx);
767 down_read(&_hash_lock);
768 hc = dm_get_mdptr(md);
769 if (!hc || hc->md != md) {
770 DMWARN("device has been removed from the dev hash table.");
777 up_read(&_hash_lock);
782 static struct dm_table *dm_get_live_or_inactive_table(struct mapped_device *md,
783 struct dm_ioctl *param,
786 return (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) ?
787 dm_get_inactive_table(md, srcu_idx) : dm_get_live_table(md, srcu_idx);
791 * Fills in a dm_ioctl structure, ready for sending back to
794 static void __dev_status(struct mapped_device *md, struct dm_ioctl *param)
796 struct gendisk *disk = dm_disk(md);
797 struct dm_table *table;
800 param->flags &= ~(DM_SUSPEND_FLAG | DM_READONLY_FLAG |
801 DM_ACTIVE_PRESENT_FLAG | DM_INTERNAL_SUSPEND_FLAG);
803 if (dm_suspended_md(md))
804 param->flags |= DM_SUSPEND_FLAG;
806 if (dm_suspended_internally_md(md))
807 param->flags |= DM_INTERNAL_SUSPEND_FLAG;
809 if (dm_test_deferred_remove_flag(md))
810 param->flags |= DM_DEFERRED_REMOVE;
812 param->dev = huge_encode_dev(disk_devt(disk));
815 * Yes, this will be out of date by the time it gets back
816 * to userland, but it is still very useful for
819 param->open_count = dm_open_count(md);
821 param->event_nr = dm_get_event_nr(md);
822 param->target_count = 0;
824 table = dm_get_live_table(md, &srcu_idx);
826 if (!(param->flags & DM_QUERY_INACTIVE_TABLE_FLAG)) {
827 if (get_disk_ro(disk))
828 param->flags |= DM_READONLY_FLAG;
829 param->target_count = dm_table_get_num_targets(table);
832 param->flags |= DM_ACTIVE_PRESENT_FLAG;
834 dm_put_live_table(md, srcu_idx);
836 if (param->flags & DM_QUERY_INACTIVE_TABLE_FLAG) {
838 table = dm_get_inactive_table(md, &srcu_idx);
840 if (!(dm_table_get_mode(table) & FMODE_WRITE))
841 param->flags |= DM_READONLY_FLAG;
842 param->target_count = dm_table_get_num_targets(table);
844 dm_put_live_table(md, srcu_idx);
848 static int dev_create(struct file *filp, struct dm_ioctl *param, size_t param_size)
850 int r, m = DM_ANY_MINOR;
851 struct mapped_device *md;
853 r = check_name(param->name);
857 if (param->flags & DM_PERSISTENT_DEV_FLAG)
858 m = MINOR(huge_decode_dev(param->dev));
860 r = dm_create(m, &md);
864 r = dm_hash_insert(param->name, *param->uuid ? param->uuid : NULL, md);
871 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
873 __dev_status(md, param);
881 * Always use UUID for lookups if it's present, otherwise use name or dev.
883 static struct hash_cell *__find_device_hash_cell(struct dm_ioctl *param)
885 struct hash_cell *hc = NULL;
888 if (*param->name || param->dev)
891 hc = __get_uuid_cell(param->uuid);
894 } else if (*param->name) {
898 hc = __get_name_cell(param->name);
901 } else if (param->dev) {
902 hc = __get_dev_cell(param->dev);
909 * Sneakily write in both the name and the uuid
910 * while we have the cell.
912 strlcpy(param->name, hc->name, sizeof(param->name));
914 strlcpy(param->uuid, hc->uuid, sizeof(param->uuid));
916 param->uuid[0] = '\0';
919 param->flags |= DM_INACTIVE_PRESENT_FLAG;
921 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
926 static struct mapped_device *find_device(struct dm_ioctl *param)
928 struct hash_cell *hc;
929 struct mapped_device *md = NULL;
931 down_read(&_hash_lock);
932 hc = __find_device_hash_cell(param);
935 up_read(&_hash_lock);
940 static int dev_remove(struct file *filp, struct dm_ioctl *param, size_t param_size)
942 struct hash_cell *hc;
943 struct mapped_device *md;
947 down_write(&_hash_lock);
948 hc = __find_device_hash_cell(param);
951 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
952 up_write(&_hash_lock);
959 * Ensure the device is not open and nothing further can open it.
961 r = dm_lock_for_deletion(md, !!(param->flags & DM_DEFERRED_REMOVE), false);
963 if (r == -EBUSY && param->flags & DM_DEFERRED_REMOVE) {
964 up_write(&_hash_lock);
968 DMDEBUG_LIMIT("unable to remove open device %s", hc->name);
969 up_write(&_hash_lock);
974 t = __hash_remove(hc);
975 up_write(&_hash_lock);
982 param->flags &= ~DM_DEFERRED_REMOVE;
984 if (!dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr))
985 param->flags |= DM_UEVENT_GENERATED_FLAG;
993 * Check a string doesn't overrun the chunk of
994 * memory we copied from userland.
996 static int invalid_str(char *str, void *end)
998 while ((void *) str < end)
1005 static int dev_rename(struct file *filp, struct dm_ioctl *param, size_t param_size)
1008 char *new_data = (char *) param + param->data_start;
1009 struct mapped_device *md;
1010 unsigned change_uuid = (param->flags & DM_UUID_FLAG) ? 1 : 0;
1012 if (new_data < param->data ||
1013 invalid_str(new_data, (void *) param + param_size) || !*new_data ||
1014 strlen(new_data) > (change_uuid ? DM_UUID_LEN - 1 : DM_NAME_LEN - 1)) {
1015 DMWARN("Invalid new mapped device name or uuid string supplied.");
1020 r = check_name(new_data);
1025 md = dm_hash_rename(param, new_data);
1029 __dev_status(md, param);
1035 static int dev_set_geometry(struct file *filp, struct dm_ioctl *param, size_t param_size)
1038 struct mapped_device *md;
1039 struct hd_geometry geometry;
1040 unsigned long indata[4];
1041 char *geostr = (char *) param + param->data_start;
1044 md = find_device(param);
1048 if (geostr < param->data ||
1049 invalid_str(geostr, (void *) param + param_size)) {
1050 DMWARN("Invalid geometry supplied.");
1054 x = sscanf(geostr, "%lu %lu %lu %lu%c", indata,
1055 indata + 1, indata + 2, indata + 3, &dummy);
1058 DMWARN("Unable to interpret geometry settings.");
1062 if (indata[0] > 65535 || indata[1] > 255 ||
1063 indata[2] > 255 || indata[3] > ULONG_MAX) {
1064 DMWARN("Geometry exceeds range limits.");
1068 geometry.cylinders = indata[0];
1069 geometry.heads = indata[1];
1070 geometry.sectors = indata[2];
1071 geometry.start = indata[3];
1073 r = dm_set_geometry(md, &geometry);
1075 param->data_size = 0;
1082 static int do_suspend(struct dm_ioctl *param)
1085 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
1086 struct mapped_device *md;
1088 md = find_device(param);
1092 if (param->flags & DM_SKIP_LOCKFS_FLAG)
1093 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
1094 if (param->flags & DM_NOFLUSH_FLAG)
1095 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
1097 if (!dm_suspended_md(md)) {
1098 r = dm_suspend(md, suspend_flags);
1103 __dev_status(md, param);
1111 static int do_resume(struct dm_ioctl *param)
1114 unsigned suspend_flags = DM_SUSPEND_LOCKFS_FLAG;
1115 struct hash_cell *hc;
1116 struct mapped_device *md;
1117 struct dm_table *new_map, *old_map = NULL;
1119 down_write(&_hash_lock);
1121 hc = __find_device_hash_cell(param);
1123 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
1124 up_write(&_hash_lock);
1130 new_map = hc->new_map;
1132 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1134 up_write(&_hash_lock);
1136 /* Do we need to load a new map ? */
1138 /* Suspend if it isn't already suspended */
1139 if (param->flags & DM_SKIP_LOCKFS_FLAG)
1140 suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
1141 if (param->flags & DM_NOFLUSH_FLAG)
1142 suspend_flags |= DM_SUSPEND_NOFLUSH_FLAG;
1143 if (!dm_suspended_md(md))
1144 dm_suspend(md, suspend_flags);
1146 old_map = dm_swap_table(md, new_map);
1147 if (IS_ERR(old_map)) {
1149 dm_table_destroy(new_map);
1151 return PTR_ERR(old_map);
1154 if (dm_table_get_mode(new_map) & FMODE_WRITE)
1155 set_disk_ro(dm_disk(md), 0);
1157 set_disk_ro(dm_disk(md), 1);
1160 if (dm_suspended_md(md)) {
1162 if (!r && !dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr))
1163 param->flags |= DM_UEVENT_GENERATED_FLAG;
1167 * Since dm_swap_table synchronizes RCU, nobody should be in
1168 * read-side critical section already.
1171 dm_table_destroy(old_map);
1174 __dev_status(md, param);
1181 * Set or unset the suspension state of a device.
1182 * If the device already is in the requested state we just return its status.
1184 static int dev_suspend(struct file *filp, struct dm_ioctl *param, size_t param_size)
1186 if (param->flags & DM_SUSPEND_FLAG)
1187 return do_suspend(param);
1189 return do_resume(param);
1193 * Copies device info back to user space, used by
1194 * the create and info ioctls.
1196 static int dev_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
1198 struct mapped_device *md;
1200 md = find_device(param);
1204 __dev_status(md, param);
1211 * Build up the status struct for each target
1213 static void retrieve_status(struct dm_table *table,
1214 struct dm_ioctl *param, size_t param_size)
1216 unsigned int i, num_targets;
1217 struct dm_target_spec *spec;
1218 char *outbuf, *outptr;
1220 size_t remaining, len, used = 0;
1221 unsigned status_flags = 0;
1223 outptr = outbuf = get_result_buffer(param, param_size, &len);
1225 if (param->flags & DM_STATUS_TABLE_FLAG)
1226 type = STATUSTYPE_TABLE;
1228 type = STATUSTYPE_INFO;
1230 /* Get all the target info */
1231 num_targets = dm_table_get_num_targets(table);
1232 for (i = 0; i < num_targets; i++) {
1233 struct dm_target *ti = dm_table_get_target(table, i);
1236 remaining = len - (outptr - outbuf);
1237 if (remaining <= sizeof(struct dm_target_spec)) {
1238 param->flags |= DM_BUFFER_FULL_FLAG;
1242 spec = (struct dm_target_spec *) outptr;
1245 spec->sector_start = ti->begin;
1246 spec->length = ti->len;
1247 strncpy(spec->target_type, ti->type->name,
1248 sizeof(spec->target_type) - 1);
1250 outptr += sizeof(struct dm_target_spec);
1251 remaining = len - (outptr - outbuf);
1252 if (remaining <= 0) {
1253 param->flags |= DM_BUFFER_FULL_FLAG;
1257 /* Get the status/table string from the target driver */
1258 if (ti->type->status) {
1259 if (param->flags & DM_NOFLUSH_FLAG)
1260 status_flags |= DM_STATUS_NOFLUSH_FLAG;
1261 ti->type->status(ti, type, status_flags, outptr, remaining);
1265 l = strlen(outptr) + 1;
1266 if (l == remaining) {
1267 param->flags |= DM_BUFFER_FULL_FLAG;
1272 used = param->data_start + (outptr - outbuf);
1274 outptr = align_ptr(outptr);
1275 spec->next = outptr - outbuf;
1279 param->data_size = used;
1281 param->target_count = num_targets;
1285 * Wait for a device to report an event
1287 static int dev_wait(struct file *filp, struct dm_ioctl *param, size_t param_size)
1290 struct mapped_device *md;
1291 struct dm_table *table;
1294 md = find_device(param);
1299 * Wait for a notification event
1301 if (dm_wait_event(md, param->event_nr)) {
1307 * The userland program is going to want to know what
1308 * changed to trigger the event, so we may as well tell
1309 * him and save an ioctl.
1311 __dev_status(md, param);
1313 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1315 retrieve_status(table, param, param_size);
1316 dm_put_live_table(md, srcu_idx);
1325 * Remember the global event number and make it possible to poll
1326 * for further events.
1328 static int dev_arm_poll(struct file *filp, struct dm_ioctl *param, size_t param_size)
1330 struct dm_file *priv = filp->private_data;
1332 priv->global_event_nr = atomic_read(&dm_global_event_nr);
1337 static inline fmode_t get_mode(struct dm_ioctl *param)
1339 fmode_t mode = FMODE_READ | FMODE_WRITE;
1341 if (param->flags & DM_READONLY_FLAG)
1347 static int next_target(struct dm_target_spec *last, uint32_t next, void *end,
1348 struct dm_target_spec **spec, char **target_params)
1350 *spec = (struct dm_target_spec *) ((unsigned char *) last + next);
1351 *target_params = (char *) (*spec + 1);
1353 if (*spec < (last + 1))
1356 return invalid_str(*target_params, end);
1359 static int populate_table(struct dm_table *table,
1360 struct dm_ioctl *param, size_t param_size)
1364 struct dm_target_spec *spec = (struct dm_target_spec *) param;
1365 uint32_t next = param->data_start;
1366 void *end = (void *) param + param_size;
1367 char *target_params;
1369 if (!param->target_count) {
1370 DMWARN("populate_table: no targets specified");
1374 for (i = 0; i < param->target_count; i++) {
1376 r = next_target(spec, next, end, &spec, &target_params);
1378 DMWARN("unable to find target");
1382 r = dm_table_add_target(table, spec->target_type,
1383 (sector_t) spec->sector_start,
1384 (sector_t) spec->length,
1387 DMWARN("error adding target to table");
1394 return dm_table_complete(table);
1397 static bool is_valid_type(enum dm_queue_mode cur, enum dm_queue_mode new)
1400 (cur == DM_TYPE_BIO_BASED && new == DM_TYPE_DAX_BIO_BASED))
1406 static int table_load(struct file *filp, struct dm_ioctl *param, size_t param_size)
1409 struct hash_cell *hc;
1410 struct dm_table *t, *old_map = NULL;
1411 struct mapped_device *md;
1412 struct target_type *immutable_target_type;
1414 md = find_device(param);
1418 r = dm_table_create(&t, get_mode(param), param->target_count, md);
1422 /* Protect md->type and md->queue against concurrent table loads. */
1423 dm_lock_md_type(md);
1424 r = populate_table(t, param, param_size);
1426 goto err_unlock_md_type;
1428 immutable_target_type = dm_get_immutable_target_type(md);
1429 if (immutable_target_type &&
1430 (immutable_target_type != dm_table_get_immutable_target_type(t)) &&
1431 !dm_table_get_wildcard_target(t)) {
1432 DMWARN("can't replace immutable target type %s",
1433 immutable_target_type->name);
1435 goto err_unlock_md_type;
1438 if (dm_get_md_type(md) == DM_TYPE_NONE) {
1439 /* Initial table load: acquire type of table. */
1440 dm_set_md_type(md, dm_table_get_type(t));
1442 /* setup md->queue to reflect md's type (may block) */
1443 r = dm_setup_md_queue(md, t);
1445 DMWARN("unable to set up device queue for new table.");
1446 goto err_unlock_md_type;
1448 } else if (!is_valid_type(dm_get_md_type(md), dm_table_get_type(t))) {
1449 DMWARN("can't change device type (old=%u vs new=%u) after initial table load.",
1450 dm_get_md_type(md), dm_table_get_type(t));
1452 goto err_unlock_md_type;
1455 dm_unlock_md_type(md);
1457 /* stage inactive table */
1458 down_write(&_hash_lock);
1459 hc = dm_get_mdptr(md);
1460 if (!hc || hc->md != md) {
1461 DMWARN("device has been removed from the dev hash table.");
1462 up_write(&_hash_lock);
1464 goto err_destroy_table;
1468 old_map = hc->new_map;
1470 up_write(&_hash_lock);
1472 param->flags |= DM_INACTIVE_PRESENT_FLAG;
1473 __dev_status(md, param);
1477 dm_table_destroy(old_map);
1485 dm_unlock_md_type(md);
1487 dm_table_destroy(t);
1494 static int table_clear(struct file *filp, struct dm_ioctl *param, size_t param_size)
1496 struct hash_cell *hc;
1497 struct mapped_device *md;
1498 struct dm_table *old_map = NULL;
1500 down_write(&_hash_lock);
1502 hc = __find_device_hash_cell(param);
1504 DMDEBUG_LIMIT("device doesn't appear to be in the dev hash table.");
1505 up_write(&_hash_lock);
1510 old_map = hc->new_map;
1514 param->flags &= ~DM_INACTIVE_PRESENT_FLAG;
1516 __dev_status(hc->md, param);
1518 up_write(&_hash_lock);
1521 dm_table_destroy(old_map);
1529 * Retrieves a list of devices used by a particular dm device.
1531 static void retrieve_deps(struct dm_table *table,
1532 struct dm_ioctl *param, size_t param_size)
1534 unsigned int count = 0;
1535 struct list_head *tmp;
1537 struct dm_dev_internal *dd;
1538 struct dm_target_deps *deps;
1540 deps = get_result_buffer(param, param_size, &len);
1543 * Count the devices.
1545 list_for_each (tmp, dm_table_get_devices(table))
1549 * Check we have enough space.
1551 needed = struct_size(deps, dev, count);
1553 param->flags |= DM_BUFFER_FULL_FLAG;
1558 * Fill in the devices.
1560 deps->count = count;
1562 list_for_each_entry (dd, dm_table_get_devices(table), list)
1563 deps->dev[count++] = huge_encode_dev(dd->dm_dev->bdev->bd_dev);
1565 param->data_size = param->data_start + needed;
1568 static int table_deps(struct file *filp, struct dm_ioctl *param, size_t param_size)
1570 struct mapped_device *md;
1571 struct dm_table *table;
1574 md = find_device(param);
1578 __dev_status(md, param);
1580 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1582 retrieve_deps(table, param, param_size);
1583 dm_put_live_table(md, srcu_idx);
1591 * Return the status of a device as a text string for each
1594 static int table_status(struct file *filp, struct dm_ioctl *param, size_t param_size)
1596 struct mapped_device *md;
1597 struct dm_table *table;
1600 md = find_device(param);
1604 __dev_status(md, param);
1606 table = dm_get_live_or_inactive_table(md, param, &srcu_idx);
1608 retrieve_status(table, param, param_size);
1609 dm_put_live_table(md, srcu_idx);
1617 * Process device-mapper dependent messages. Messages prefixed with '@'
1618 * are processed by the DM core. All others are delivered to the target.
1619 * Returns a number <= 1 if message was processed by device mapper.
1620 * Returns 2 if message should be delivered to the target.
1622 static int message_for_md(struct mapped_device *md, unsigned argc, char **argv,
1623 char *result, unsigned maxlen)
1628 return 2; /* no '@' prefix, deliver to target */
1630 if (!strcasecmp(argv[0], "@cancel_deferred_remove")) {
1632 DMERR("Invalid arguments for @cancel_deferred_remove");
1635 return dm_cancel_deferred_remove(md);
1638 r = dm_stats_message(md, argc, argv, result, maxlen);
1642 DMERR("Unsupported message sent to DM core: %s", argv[0]);
1647 * Pass a message to the target that's at the supplied device offset.
1649 static int target_message(struct file *filp, struct dm_ioctl *param, size_t param_size)
1653 struct mapped_device *md;
1654 struct dm_table *table;
1655 struct dm_target *ti;
1656 struct dm_target_msg *tmsg = (void *) param + param->data_start;
1658 char *result = get_result_buffer(param, param_size, &maxlen);
1661 md = find_device(param);
1665 if (tmsg < (struct dm_target_msg *) param->data ||
1666 invalid_str(tmsg->message, (void *) param + param_size)) {
1667 DMWARN("Invalid target message parameters.");
1672 r = dm_split_args(&argc, &argv, tmsg->message);
1674 DMWARN("Failed to split target message parameters");
1679 DMWARN("Empty message received.");
1684 r = message_for_md(md, argc, argv, result, maxlen);
1688 table = dm_get_live_table(md, &srcu_idx);
1692 if (dm_deleting_md(md)) {
1697 ti = dm_table_find_target(table, tmsg->sector);
1699 DMWARN("Target message sector outside device.");
1701 } else if (ti->type->message)
1702 r = ti->type->message(ti, argc, argv, result, maxlen);
1704 DMWARN("Target type does not support messages");
1709 dm_put_live_table(md, srcu_idx);
1714 __dev_status(md, param);
1717 param->flags |= DM_DATA_OUT_FLAG;
1718 if (dm_message_test_buffer_overflow(result, maxlen))
1719 param->flags |= DM_BUFFER_FULL_FLAG;
1721 param->data_size = param->data_start + strlen(result) + 1;
1730 * The ioctl parameter block consists of two parts, a dm_ioctl struct
1731 * followed by a data buffer. This flag is set if the second part,
1732 * which has a variable size, is not used by the function processing
1735 #define IOCTL_FLAGS_NO_PARAMS 1
1736 #define IOCTL_FLAGS_ISSUE_GLOBAL_EVENT 2
1738 /*-----------------------------------------------------------------
1739 * Implementation of open/close/ioctl on the special char
1741 *---------------------------------------------------------------*/
1742 static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags)
1744 static const struct {
1749 {DM_VERSION_CMD, 0, NULL}, /* version is dealt with elsewhere */
1750 {DM_REMOVE_ALL_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, remove_all},
1751 {DM_LIST_DEVICES_CMD, 0, list_devices},
1753 {DM_DEV_CREATE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_create},
1754 {DM_DEV_REMOVE_CMD, IOCTL_FLAGS_NO_PARAMS | IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_remove},
1755 {DM_DEV_RENAME_CMD, IOCTL_FLAGS_ISSUE_GLOBAL_EVENT, dev_rename},
1756 {DM_DEV_SUSPEND_CMD, IOCTL_FLAGS_NO_PARAMS, dev_suspend},
1757 {DM_DEV_STATUS_CMD, IOCTL_FLAGS_NO_PARAMS, dev_status},
1758 {DM_DEV_WAIT_CMD, 0, dev_wait},
1760 {DM_TABLE_LOAD_CMD, 0, table_load},
1761 {DM_TABLE_CLEAR_CMD, IOCTL_FLAGS_NO_PARAMS, table_clear},
1762 {DM_TABLE_DEPS_CMD, 0, table_deps},
1763 {DM_TABLE_STATUS_CMD, 0, table_status},
1765 {DM_LIST_VERSIONS_CMD, 0, list_versions},
1767 {DM_TARGET_MSG_CMD, 0, target_message},
1768 {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry},
1769 {DM_DEV_ARM_POLL, IOCTL_FLAGS_NO_PARAMS, dev_arm_poll},
1770 {DM_GET_TARGET_VERSION, 0, get_target_version},
1773 if (unlikely(cmd >= ARRAY_SIZE(_ioctls)))
1776 *ioctl_flags = _ioctls[cmd].flags;
1777 return _ioctls[cmd].fn;
1781 * As well as checking the version compatibility this always
1782 * copies the kernel interface version out.
1784 static int check_version(unsigned int cmd, struct dm_ioctl __user *user)
1786 uint32_t version[3];
1789 if (copy_from_user(version, user->version, sizeof(version)))
1792 if ((DM_VERSION_MAJOR != version[0]) ||
1793 (DM_VERSION_MINOR < version[1])) {
1794 DMWARN("ioctl interface mismatch: "
1795 "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1796 DM_VERSION_MAJOR, DM_VERSION_MINOR,
1797 DM_VERSION_PATCHLEVEL,
1798 version[0], version[1], version[2], cmd);
1803 * Fill in the kernel version.
1805 version[0] = DM_VERSION_MAJOR;
1806 version[1] = DM_VERSION_MINOR;
1807 version[2] = DM_VERSION_PATCHLEVEL;
1808 if (copy_to_user(user->version, version, sizeof(version)))
1814 #define DM_PARAMS_MALLOC 0x0001 /* Params allocated with kvmalloc() */
1815 #define DM_WIPE_BUFFER 0x0010 /* Wipe input buffer before returning from ioctl */
1817 static void free_params(struct dm_ioctl *param, size_t param_size, int param_flags)
1819 if (param_flags & DM_WIPE_BUFFER)
1820 memset(param, 0, param_size);
1822 if (param_flags & DM_PARAMS_MALLOC)
1826 static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl *param_kernel,
1827 int ioctl_flags, struct dm_ioctl **param, int *param_flags)
1829 struct dm_ioctl *dmi;
1831 const size_t minimum_data_size = offsetof(struct dm_ioctl, data);
1834 if (copy_from_user(param_kernel, user, minimum_data_size))
1837 if (param_kernel->data_size < minimum_data_size)
1840 secure_data = param_kernel->flags & DM_SECURE_DATA_FLAG;
1842 *param_flags = secure_data ? DM_WIPE_BUFFER : 0;
1844 if (ioctl_flags & IOCTL_FLAGS_NO_PARAMS) {
1846 dmi->data_size = minimum_data_size;
1851 * Use __GFP_HIGH to avoid low memory issues when a device is
1852 * suspended and the ioctl is needed to resume it.
1853 * Use kmalloc() rather than vmalloc() when we can.
1856 noio_flag = memalloc_noio_save();
1857 dmi = kvmalloc(param_kernel->data_size, GFP_KERNEL | __GFP_HIGH);
1858 memalloc_noio_restore(noio_flag);
1861 if (secure_data && clear_user(user, param_kernel->data_size))
1866 *param_flags |= DM_PARAMS_MALLOC;
1868 /* Copy from param_kernel (which was already copied from user) */
1869 memcpy(dmi, param_kernel, minimum_data_size);
1871 if (copy_from_user(&dmi->data, (char __user *)user + minimum_data_size,
1872 param_kernel->data_size - minimum_data_size))
1875 /* Wipe the user buffer so we do not return it to userspace */
1876 if (secure_data && clear_user(user, param_kernel->data_size))
1883 free_params(dmi, param_kernel->data_size, *param_flags);
1888 static int validate_params(uint cmd, struct dm_ioctl *param)
1890 /* Always clear this flag */
1891 param->flags &= ~DM_BUFFER_FULL_FLAG;
1892 param->flags &= ~DM_UEVENT_GENERATED_FLAG;
1893 param->flags &= ~DM_SECURE_DATA_FLAG;
1894 param->flags &= ~DM_DATA_OUT_FLAG;
1896 /* Ignores parameters */
1897 if (cmd == DM_REMOVE_ALL_CMD ||
1898 cmd == DM_LIST_DEVICES_CMD ||
1899 cmd == DM_LIST_VERSIONS_CMD)
1902 if (cmd == DM_DEV_CREATE_CMD) {
1903 if (!*param->name) {
1904 DMWARN("name not supplied when creating device");
1907 } else if (*param->uuid && *param->name) {
1908 DMWARN("only supply one of name or uuid, cmd(%u)", cmd);
1912 /* Ensure strings are terminated */
1913 param->name[DM_NAME_LEN - 1] = '\0';
1914 param->uuid[DM_UUID_LEN - 1] = '\0';
1919 static int ctl_ioctl(struct file *file, uint command, struct dm_ioctl __user *user)
1925 struct dm_ioctl *param;
1927 size_t input_param_size;
1928 struct dm_ioctl param_kernel;
1930 /* only root can play with this */
1931 if (!capable(CAP_SYS_ADMIN))
1934 if (_IOC_TYPE(command) != DM_IOCTL)
1937 cmd = _IOC_NR(command);
1940 * Check the interface version passed in. This also
1941 * writes out the kernel's interface version.
1943 r = check_version(cmd, user);
1948 * Nothing more to do for the version command.
1950 if (cmd == DM_VERSION_CMD)
1953 fn = lookup_ioctl(cmd, &ioctl_flags);
1955 DMWARN("dm_ctl_ioctl: unknown command 0x%x", command);
1960 * Copy the parameters into kernel space.
1962 r = copy_params(user, ¶m_kernel, ioctl_flags, ¶m, ¶m_flags);
1967 input_param_size = param->data_size;
1968 r = validate_params(cmd, param);
1972 param->data_size = offsetof(struct dm_ioctl, data);
1973 r = fn(file, param, input_param_size);
1975 if (unlikely(param->flags & DM_BUFFER_FULL_FLAG) &&
1976 unlikely(ioctl_flags & IOCTL_FLAGS_NO_PARAMS))
1977 DMERR("ioctl %d tried to output some data but has IOCTL_FLAGS_NO_PARAMS set", cmd);
1979 if (!r && ioctl_flags & IOCTL_FLAGS_ISSUE_GLOBAL_EVENT)
1980 dm_issue_global_event();
1983 * Copy the results back to userland.
1985 if (!r && copy_to_user(user, param, param->data_size))
1989 free_params(param, input_param_size, param_flags);
1993 static long dm_ctl_ioctl(struct file *file, uint command, ulong u)
1995 return (long)ctl_ioctl(file, command, (struct dm_ioctl __user *)u);
1998 #ifdef CONFIG_COMPAT
1999 static long dm_compat_ctl_ioctl(struct file *file, uint command, ulong u)
2001 return (long)dm_ctl_ioctl(file, command, (ulong) compat_ptr(u));
2004 #define dm_compat_ctl_ioctl NULL
2007 static int dm_open(struct inode *inode, struct file *filp)
2010 struct dm_file *priv;
2012 r = nonseekable_open(inode, filp);
2016 priv = filp->private_data = kmalloc(sizeof(struct dm_file), GFP_KERNEL);
2020 priv->global_event_nr = atomic_read(&dm_global_event_nr);
2025 static int dm_release(struct inode *inode, struct file *filp)
2027 kfree(filp->private_data);
2031 static __poll_t dm_poll(struct file *filp, poll_table *wait)
2033 struct dm_file *priv = filp->private_data;
2036 poll_wait(filp, &dm_global_eventq, wait);
2038 if ((int)(atomic_read(&dm_global_event_nr) - priv->global_event_nr) > 0)
2044 static const struct file_operations _ctl_fops = {
2046 .release = dm_release,
2048 .unlocked_ioctl = dm_ctl_ioctl,
2049 .compat_ioctl = dm_compat_ctl_ioctl,
2050 .owner = THIS_MODULE,
2051 .llseek = noop_llseek,
2054 static struct miscdevice _dm_misc = {
2055 .minor = MAPPER_CTRL_MINOR,
2057 .nodename = DM_DIR "/" DM_CONTROL_NODE,
2061 MODULE_ALIAS_MISCDEV(MAPPER_CTRL_MINOR);
2062 MODULE_ALIAS("devname:" DM_DIR "/" DM_CONTROL_NODE);
2065 * Create misc character device and link to DM_DIR/control.
2067 int __init dm_interface_init(void)
2071 r = misc_register(&_dm_misc);
2073 DMERR("misc_register failed for control device");
2077 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR,
2078 DM_VERSION_MINOR, DM_VERSION_PATCHLEVEL, DM_VERSION_EXTRA,
2083 void dm_interface_exit(void)
2085 misc_deregister(&_dm_misc);
2090 * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
2091 * @md: Pointer to mapped_device
2092 * @name: Buffer (size DM_NAME_LEN) for name
2093 * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
2095 int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
2098 struct hash_cell *hc;
2103 mutex_lock(&dm_hash_cells_mutex);
2104 hc = dm_get_mdptr(md);
2105 if (!hc || hc->md != md) {
2111 strcpy(name, hc->name);
2113 strcpy(uuid, hc->uuid ? : "");
2116 mutex_unlock(&dm_hash_cells_mutex);
2120 EXPORT_SYMBOL_GPL(dm_copy_name_and_uuid);
2123 * dm_early_create - create a mapped device in early boot.
2125 * @dmi: Contains main information of the device mapping to be created.
2126 * @spec_array: array of pointers to struct dm_target_spec. Describes the
2127 * mapping table of the device.
2128 * @target_params_array: array of strings with the parameters to a specific
2131 * Instead of having the struct dm_target_spec and the parameters for every
2132 * target embedded at the end of struct dm_ioctl (as performed in a normal
2133 * ioctl), pass them as arguments, so the caller doesn't need to serialize them.
2134 * The size of the spec_array and target_params_array is given by
2135 * @dmi->target_count.
2136 * This function is supposed to be called in early boot, so locking mechanisms
2137 * to protect against concurrent loads are not required.
2139 int __init dm_early_create(struct dm_ioctl *dmi,
2140 struct dm_target_spec **spec_array,
2141 char **target_params_array)
2143 int r, m = DM_ANY_MINOR;
2144 struct dm_table *t, *old_map;
2145 struct mapped_device *md;
2148 if (!dmi->target_count)
2151 r = check_name(dmi->name);
2155 if (dmi->flags & DM_PERSISTENT_DEV_FLAG)
2156 m = MINOR(huge_decode_dev(dmi->dev));
2158 /* alloc dm device */
2159 r = dm_create(m, &md);
2164 r = dm_hash_insert(dmi->name, *dmi->uuid ? dmi->uuid : NULL, md);
2166 goto err_destroy_dm;
2169 r = dm_table_create(&t, get_mode(dmi), dmi->target_count, md);
2171 goto err_hash_remove;
2174 for (i = 0; i < dmi->target_count; i++) {
2175 r = dm_table_add_target(t, spec_array[i]->target_type,
2176 (sector_t) spec_array[i]->sector_start,
2177 (sector_t) spec_array[i]->length,
2178 target_params_array[i]);
2180 DMWARN("error adding target to table");
2181 goto err_destroy_table;
2186 r = dm_table_complete(t);
2188 goto err_destroy_table;
2190 md->type = dm_table_get_type(t);
2191 /* setup md->queue to reflect md's type (may block) */
2192 r = dm_setup_md_queue(md, t);
2194 DMWARN("unable to set up device queue for new table.");
2195 goto err_destroy_table;
2200 old_map = dm_swap_table(md, t);
2201 if (IS_ERR(old_map)) {
2202 r = PTR_ERR(old_map);
2203 goto err_destroy_table;
2205 set_disk_ro(dm_disk(md), !!(dmi->flags & DM_READONLY_FLAG));
2210 goto err_destroy_table;
2212 DMINFO("%s (%s) is ready", md->disk->disk_name, dmi->name);
2217 dm_table_destroy(t);
2219 (void) __hash_remove(__get_name_cell(dmi->name));
2220 /* release reference from __get_name_cell */