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/dm-ioctl.h>
17 #include <linux/hdreg.h>
18 #include <linux/compat.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
);
60 * Protects use of mdptr to obtain hash cell name and uuid from mapped device.
62 static DEFINE_MUTEX(dm_hash_cells_mutex
);
64 static void init_buckets(struct list_head
*buckets
)
68 for (i
= 0; i
< NUM_BUCKETS
; i
++)
69 INIT_LIST_HEAD(buckets
+ i
);
72 static int dm_hash_init(void)
74 init_buckets(_name_buckets
);
75 init_buckets(_uuid_buckets
);
79 static void dm_hash_exit(void)
81 dm_hash_remove_all(0);
84 /*-----------------------------------------------------------------
86 * We're not really concerned with the str hash function being
87 * fast since it's only used by the ioctl interface.
88 *---------------------------------------------------------------*/
89 static unsigned int hash_str(const char *str
)
91 const unsigned int hash_mult
= 2654435387U;
95 h
= (h
+ (unsigned int) *str
++) * hash_mult
;
97 return h
& MASK_BUCKETS
;
100 /*-----------------------------------------------------------------
101 * Code for looking up a device by name
102 *---------------------------------------------------------------*/
103 static struct hash_cell
*__get_name_cell(const char *str
)
105 struct hash_cell
*hc
;
106 unsigned int h
= hash_str(str
);
108 list_for_each_entry (hc
, _name_buckets
+ h
, name_list
)
109 if (!strcmp(hc
->name
, str
)) {
117 static struct hash_cell
*__get_uuid_cell(const char *str
)
119 struct hash_cell
*hc
;
120 unsigned int h
= hash_str(str
);
122 list_for_each_entry (hc
, _uuid_buckets
+ h
, uuid_list
)
123 if (!strcmp(hc
->uuid
, str
)) {
131 /*-----------------------------------------------------------------
132 * Inserting, removing and renaming a device.
133 *---------------------------------------------------------------*/
134 static struct hash_cell
*alloc_cell(const char *name
, const char *uuid
,
135 struct mapped_device
*md
)
137 struct hash_cell
*hc
;
139 hc
= kmalloc(sizeof(*hc
), GFP_KERNEL
);
143 hc
->name
= kstrdup(name
, GFP_KERNEL
);
153 hc
->uuid
= kstrdup(uuid
, GFP_KERNEL
);
161 INIT_LIST_HEAD(&hc
->name_list
);
162 INIT_LIST_HEAD(&hc
->uuid_list
);
168 static void free_cell(struct hash_cell
*hc
)
178 * The kdev_t and uuid of a device can never change once it is
179 * initially inserted.
181 static int dm_hash_insert(const char *name
, const char *uuid
, struct mapped_device
*md
)
183 struct hash_cell
*cell
, *hc
;
186 * Allocate the new cells.
188 cell
= alloc_cell(name
, uuid
, md
);
193 * Insert the cell into both hash tables.
195 down_write(&_hash_lock
);
196 hc
= __get_name_cell(name
);
202 list_add(&cell
->name_list
, _name_buckets
+ hash_str(name
));
205 hc
= __get_uuid_cell(uuid
);
207 list_del(&cell
->name_list
);
211 list_add(&cell
->uuid_list
, _uuid_buckets
+ hash_str(uuid
));
214 mutex_lock(&dm_hash_cells_mutex
);
215 dm_set_mdptr(md
, cell
);
216 mutex_unlock(&dm_hash_cells_mutex
);
217 up_write(&_hash_lock
);
222 up_write(&_hash_lock
);
227 static void __hash_remove(struct hash_cell
*hc
)
229 struct dm_table
*table
;
231 /* remove from the dev hash */
232 list_del(&hc
->uuid_list
);
233 list_del(&hc
->name_list
);
234 mutex_lock(&dm_hash_cells_mutex
);
235 dm_set_mdptr(hc
->md
, NULL
);
236 mutex_unlock(&dm_hash_cells_mutex
);
238 table
= dm_get_live_table(hc
->md
);
240 dm_table_event(table
);
245 dm_table_destroy(hc
->new_map
);
250 static void dm_hash_remove_all(int keep_open_devices
)
252 int i
, dev_skipped
, dev_removed
;
253 struct hash_cell
*hc
;
254 struct list_head
*tmp
, *n
;
256 down_write(&_hash_lock
);
259 dev_skipped
= dev_removed
= 0;
260 for (i
= 0; i
< NUM_BUCKETS
; i
++) {
261 list_for_each_safe (tmp
, n
, _name_buckets
+ i
) {
262 hc
= list_entry(tmp
, struct hash_cell
, name_list
);
264 if (keep_open_devices
&&
265 dm_lock_for_deletion(hc
->md
)) {
275 * Some mapped devices may be using other mapped devices, so if any
276 * still exist, repeat until we make no further progress.
282 DMWARN("remove_all left %d open device(s)", dev_skipped
);
285 up_write(&_hash_lock
);
288 static int dm_hash_rename(uint32_t cookie
, const char *old
, const char *new)
290 char *new_name
, *old_name
;
291 struct hash_cell
*hc
;
292 struct dm_table
*table
;
297 new_name
= kstrdup(new, GFP_KERNEL
);
301 down_write(&_hash_lock
);
306 hc
= __get_name_cell(new);
308 DMWARN("asked to rename to an already existing name %s -> %s",
311 up_write(&_hash_lock
);
317 * Is there such a device as 'old' ?
319 hc
= __get_name_cell(old
);
321 DMWARN("asked to rename a non existent device %s -> %s",
323 up_write(&_hash_lock
);
329 * rename and move the name cell.
331 list_del(&hc
->name_list
);
333 mutex_lock(&dm_hash_cells_mutex
);
335 mutex_unlock(&dm_hash_cells_mutex
);
336 list_add(&hc
->name_list
, _name_buckets
+ hash_str(new_name
));
339 * Wake up any dm event waiters.
341 table
= dm_get_live_table(hc
->md
);
343 dm_table_event(table
);
347 dm_kobject_uevent(hc
->md
, KOBJ_CHANGE
, cookie
);
350 up_write(&_hash_lock
);
355 /*-----------------------------------------------------------------
356 * Implementation of the ioctl commands
357 *---------------------------------------------------------------*/
359 * All the ioctl commands get dispatched to functions with this
362 typedef int (*ioctl_fn
)(struct dm_ioctl
*param
, size_t param_size
);
364 static int remove_all(struct dm_ioctl
*param
, size_t param_size
)
366 dm_hash_remove_all(1);
367 param
->data_size
= 0;
372 * Round up the ptr to an 8-byte boundary.
375 static inline void *align_ptr(void *ptr
)
377 return (void *) (((size_t) (ptr
+ ALIGN_MASK
)) & ~ALIGN_MASK
);
381 * Retrieves the data payload buffer from an already allocated
384 static void *get_result_buffer(struct dm_ioctl
*param
, size_t param_size
,
387 param
->data_start
= align_ptr(param
+ 1) - (void *) param
;
389 if (param
->data_start
< param_size
)
390 *len
= param_size
- param
->data_start
;
394 return ((void *) param
) + param
->data_start
;
397 static int list_devices(struct dm_ioctl
*param
, size_t param_size
)
400 struct hash_cell
*hc
;
401 size_t len
, needed
= 0;
402 struct gendisk
*disk
;
403 struct dm_name_list
*nl
, *old_nl
= NULL
;
405 down_write(&_hash_lock
);
408 * Loop through all the devices working out how much
411 for (i
= 0; i
< NUM_BUCKETS
; i
++) {
412 list_for_each_entry (hc
, _name_buckets
+ i
, name_list
) {
413 needed
+= sizeof(struct dm_name_list
);
414 needed
+= strlen(hc
->name
) + 1;
415 needed
+= ALIGN_MASK
;
420 * Grab our output buffer.
422 nl
= get_result_buffer(param
, param_size
, &len
);
424 param
->flags
|= DM_BUFFER_FULL_FLAG
;
427 param
->data_size
= param
->data_start
+ needed
;
429 nl
->dev
= 0; /* Flags no data */
432 * Now loop through filling out the names.
434 for (i
= 0; i
< NUM_BUCKETS
; i
++) {
435 list_for_each_entry (hc
, _name_buckets
+ i
, name_list
) {
437 old_nl
->next
= (uint32_t) ((void *) nl
-
439 disk
= dm_disk(hc
->md
);
440 nl
->dev
= huge_encode_dev(disk_devt(disk
));
442 strcpy(nl
->name
, hc
->name
);
445 nl
= align_ptr(((void *) ++nl
) + strlen(hc
->name
) + 1);
450 up_write(&_hash_lock
);
454 static void list_version_get_needed(struct target_type
*tt
, void *needed_param
)
456 size_t *needed
= needed_param
;
458 *needed
+= sizeof(struct dm_target_versions
);
459 *needed
+= strlen(tt
->name
);
460 *needed
+= ALIGN_MASK
;
463 static void list_version_get_info(struct target_type
*tt
, void *param
)
465 struct vers_iter
*info
= param
;
467 /* Check space - it might have changed since the first iteration */
468 if ((char *)info
->vers
+ sizeof(tt
->version
) + strlen(tt
->name
) + 1 >
471 info
->flags
= DM_BUFFER_FULL_FLAG
;
476 info
->old_vers
->next
= (uint32_t) ((void *)info
->vers
-
477 (void *)info
->old_vers
);
478 info
->vers
->version
[0] = tt
->version
[0];
479 info
->vers
->version
[1] = tt
->version
[1];
480 info
->vers
->version
[2] = tt
->version
[2];
481 info
->vers
->next
= 0;
482 strcpy(info
->vers
->name
, tt
->name
);
484 info
->old_vers
= info
->vers
;
485 info
->vers
= align_ptr(((void *) ++info
->vers
) + strlen(tt
->name
) + 1);
488 static int list_versions(struct dm_ioctl
*param
, size_t param_size
)
490 size_t len
, needed
= 0;
491 struct dm_target_versions
*vers
;
492 struct vers_iter iter_info
;
495 * Loop through all the devices working out how much
498 dm_target_iterate(list_version_get_needed
, &needed
);
501 * Grab our output buffer.
503 vers
= get_result_buffer(param
, param_size
, &len
);
505 param
->flags
|= DM_BUFFER_FULL_FLAG
;
508 param
->data_size
= param
->data_start
+ needed
;
510 iter_info
.param_size
= param_size
;
511 iter_info
.old_vers
= NULL
;
512 iter_info
.vers
= vers
;
514 iter_info
.end
= (char *)vers
+len
;
517 * Now loop through filling out the names & versions.
519 dm_target_iterate(list_version_get_info
, &iter_info
);
520 param
->flags
|= iter_info
.flags
;
526 static int check_name(const char *name
)
528 if (strchr(name
, '/')) {
529 DMWARN("invalid device name");
537 * On successful return, the caller must not attempt to acquire
538 * _hash_lock without first calling dm_table_put, because dm_table_destroy
539 * waits for this dm_table_put and could be called under this lock.
541 static struct dm_table
*dm_get_inactive_table(struct mapped_device
*md
)
543 struct hash_cell
*hc
;
544 struct dm_table
*table
= NULL
;
546 down_read(&_hash_lock
);
547 hc
= dm_get_mdptr(md
);
548 if (!hc
|| hc
->md
!= md
) {
549 DMWARN("device has been removed from the dev hash table.");
558 up_read(&_hash_lock
);
563 static struct dm_table
*dm_get_live_or_inactive_table(struct mapped_device
*md
,
564 struct dm_ioctl
*param
)
566 return (param
->flags
& DM_QUERY_INACTIVE_TABLE_FLAG
) ?
567 dm_get_inactive_table(md
) : dm_get_live_table(md
);
571 * Fills in a dm_ioctl structure, ready for sending back to
574 static int __dev_status(struct mapped_device
*md
, struct dm_ioctl
*param
)
576 struct gendisk
*disk
= dm_disk(md
);
577 struct dm_table
*table
;
579 param
->flags
&= ~(DM_SUSPEND_FLAG
| DM_READONLY_FLAG
|
580 DM_ACTIVE_PRESENT_FLAG
);
582 if (dm_suspended_md(md
))
583 param
->flags
|= DM_SUSPEND_FLAG
;
585 param
->dev
= huge_encode_dev(disk_devt(disk
));
588 * Yes, this will be out of date by the time it gets back
589 * to userland, but it is still very useful for
592 param
->open_count
= dm_open_count(md
);
594 param
->event_nr
= dm_get_event_nr(md
);
595 param
->target_count
= 0;
597 table
= dm_get_live_table(md
);
599 if (!(param
->flags
& DM_QUERY_INACTIVE_TABLE_FLAG
)) {
600 if (get_disk_ro(disk
))
601 param
->flags
|= DM_READONLY_FLAG
;
602 param
->target_count
= dm_table_get_num_targets(table
);
606 param
->flags
|= DM_ACTIVE_PRESENT_FLAG
;
609 if (param
->flags
& DM_QUERY_INACTIVE_TABLE_FLAG
) {
610 table
= dm_get_inactive_table(md
);
612 if (!(dm_table_get_mode(table
) & FMODE_WRITE
))
613 param
->flags
|= DM_READONLY_FLAG
;
614 param
->target_count
= dm_table_get_num_targets(table
);
622 static int dev_create(struct dm_ioctl
*param
, size_t param_size
)
624 int r
, m
= DM_ANY_MINOR
;
625 struct mapped_device
*md
;
627 r
= check_name(param
->name
);
631 if (param
->flags
& DM_PERSISTENT_DEV_FLAG
)
632 m
= MINOR(huge_decode_dev(param
->dev
));
634 r
= dm_create(m
, &md
);
638 r
= dm_hash_insert(param
->name
, *param
->uuid
? param
->uuid
: NULL
, md
);
644 param
->flags
&= ~DM_INACTIVE_PRESENT_FLAG
;
646 r
= __dev_status(md
, param
);
653 * Always use UUID for lookups if it's present, otherwise use name or dev.
655 static struct hash_cell
*__find_device_hash_cell(struct dm_ioctl
*param
)
657 struct mapped_device
*md
;
661 return __get_uuid_cell(param
->uuid
);
664 return __get_name_cell(param
->name
);
666 md
= dm_get_md(huge_decode_dev(param
->dev
));
670 mdptr
= dm_get_mdptr(md
);
678 static struct mapped_device
*find_device(struct dm_ioctl
*param
)
680 struct hash_cell
*hc
;
681 struct mapped_device
*md
= NULL
;
683 down_read(&_hash_lock
);
684 hc
= __find_device_hash_cell(param
);
689 * Sneakily write in both the name and the uuid
690 * while we have the cell.
692 strlcpy(param
->name
, hc
->name
, sizeof(param
->name
));
694 strlcpy(param
->uuid
, hc
->uuid
, sizeof(param
->uuid
));
696 param
->uuid
[0] = '\0';
699 param
->flags
|= DM_INACTIVE_PRESENT_FLAG
;
701 param
->flags
&= ~DM_INACTIVE_PRESENT_FLAG
;
703 up_read(&_hash_lock
);
708 static int dev_remove(struct dm_ioctl
*param
, size_t param_size
)
710 struct hash_cell
*hc
;
711 struct mapped_device
*md
;
714 down_write(&_hash_lock
);
715 hc
= __find_device_hash_cell(param
);
718 DMWARN("device doesn't appear to be in the dev hash table.");
719 up_write(&_hash_lock
);
726 * Ensure the device is not open and nothing further can open it.
728 r
= dm_lock_for_deletion(md
);
730 DMWARN("unable to remove open device %s", hc
->name
);
731 up_write(&_hash_lock
);
737 up_write(&_hash_lock
);
739 dm_kobject_uevent(md
, KOBJ_REMOVE
, param
->event_nr
);
742 param
->data_size
= 0;
747 * Check a string doesn't overrun the chunk of
748 * memory we copied from userland.
750 static int invalid_str(char *str
, void *end
)
752 while ((void *) str
< end
)
759 static int dev_rename(struct dm_ioctl
*param
, size_t param_size
)
762 char *new_name
= (char *) param
+ param
->data_start
;
764 if (new_name
< param
->data
||
765 invalid_str(new_name
, (void *) param
+ param_size
) ||
766 strlen(new_name
) > DM_NAME_LEN
- 1) {
767 DMWARN("Invalid new logical volume name supplied.");
771 r
= check_name(new_name
);
775 param
->data_size
= 0;
776 return dm_hash_rename(param
->event_nr
, param
->name
, new_name
);
779 static int dev_set_geometry(struct dm_ioctl
*param
, size_t param_size
)
782 struct mapped_device
*md
;
783 struct hd_geometry geometry
;
784 unsigned long indata
[4];
785 char *geostr
= (char *) param
+ param
->data_start
;
787 md
= find_device(param
);
791 if (geostr
< param
->data
||
792 invalid_str(geostr
, (void *) param
+ param_size
)) {
793 DMWARN("Invalid geometry supplied.");
797 x
= sscanf(geostr
, "%lu %lu %lu %lu", indata
,
798 indata
+ 1, indata
+ 2, indata
+ 3);
801 DMWARN("Unable to interpret geometry settings.");
805 if (indata
[0] > 65535 || indata
[1] > 255 ||
806 indata
[2] > 255 || indata
[3] > ULONG_MAX
) {
807 DMWARN("Geometry exceeds range limits.");
811 geometry
.cylinders
= indata
[0];
812 geometry
.heads
= indata
[1];
813 geometry
.sectors
= indata
[2];
814 geometry
.start
= indata
[3];
816 r
= dm_set_geometry(md
, &geometry
);
818 r
= __dev_status(md
, param
);
820 param
->data_size
= 0;
827 static int do_suspend(struct dm_ioctl
*param
)
830 unsigned suspend_flags
= DM_SUSPEND_LOCKFS_FLAG
;
831 struct mapped_device
*md
;
833 md
= find_device(param
);
837 if (param
->flags
& DM_SKIP_LOCKFS_FLAG
)
838 suspend_flags
&= ~DM_SUSPEND_LOCKFS_FLAG
;
839 if (param
->flags
& DM_NOFLUSH_FLAG
)
840 suspend_flags
|= DM_SUSPEND_NOFLUSH_FLAG
;
842 if (!dm_suspended_md(md
))
843 r
= dm_suspend(md
, suspend_flags
);
846 r
= __dev_status(md
, param
);
852 static int do_resume(struct dm_ioctl
*param
)
855 unsigned suspend_flags
= DM_SUSPEND_LOCKFS_FLAG
;
856 struct hash_cell
*hc
;
857 struct mapped_device
*md
;
858 struct dm_table
*new_map
, *old_map
= NULL
;
860 down_write(&_hash_lock
);
862 hc
= __find_device_hash_cell(param
);
864 DMWARN("device doesn't appear to be in the dev hash table.");
865 up_write(&_hash_lock
);
871 new_map
= hc
->new_map
;
873 param
->flags
&= ~DM_INACTIVE_PRESENT_FLAG
;
875 up_write(&_hash_lock
);
877 /* Do we need to load a new map ? */
879 /* Suspend if it isn't already suspended */
880 if (param
->flags
& DM_SKIP_LOCKFS_FLAG
)
881 suspend_flags
&= ~DM_SUSPEND_LOCKFS_FLAG
;
882 if (param
->flags
& DM_NOFLUSH_FLAG
)
883 suspend_flags
|= DM_SUSPEND_NOFLUSH_FLAG
;
884 if (!dm_suspended_md(md
))
885 dm_suspend(md
, suspend_flags
);
887 old_map
= dm_swap_table(md
, new_map
);
888 if (IS_ERR(old_map
)) {
889 dm_table_destroy(new_map
);
891 return PTR_ERR(old_map
);
894 if (dm_table_get_mode(new_map
) & FMODE_WRITE
)
895 set_disk_ro(dm_disk(md
), 0);
897 set_disk_ro(dm_disk(md
), 1);
900 if (dm_suspended_md(md
))
904 dm_table_destroy(old_map
);
907 dm_kobject_uevent(md
, KOBJ_CHANGE
, param
->event_nr
);
908 r
= __dev_status(md
, param
);
916 * Set or unset the suspension state of a device.
917 * If the device already is in the requested state we just return its status.
919 static int dev_suspend(struct dm_ioctl
*param
, size_t param_size
)
921 if (param
->flags
& DM_SUSPEND_FLAG
)
922 return do_suspend(param
);
924 return do_resume(param
);
928 * Copies device info back to user space, used by
929 * the create and info ioctls.
931 static int dev_status(struct dm_ioctl
*param
, size_t param_size
)
934 struct mapped_device
*md
;
936 md
= find_device(param
);
940 r
= __dev_status(md
, param
);
946 * Build up the status struct for each target
948 static void retrieve_status(struct dm_table
*table
,
949 struct dm_ioctl
*param
, size_t param_size
)
951 unsigned int i
, num_targets
;
952 struct dm_target_spec
*spec
;
953 char *outbuf
, *outptr
;
955 size_t remaining
, len
, used
= 0;
957 outptr
= outbuf
= get_result_buffer(param
, param_size
, &len
);
959 if (param
->flags
& DM_STATUS_TABLE_FLAG
)
960 type
= STATUSTYPE_TABLE
;
962 type
= STATUSTYPE_INFO
;
964 /* Get all the target info */
965 num_targets
= dm_table_get_num_targets(table
);
966 for (i
= 0; i
< num_targets
; i
++) {
967 struct dm_target
*ti
= dm_table_get_target(table
, i
);
969 remaining
= len
- (outptr
- outbuf
);
970 if (remaining
<= sizeof(struct dm_target_spec
)) {
971 param
->flags
|= DM_BUFFER_FULL_FLAG
;
975 spec
= (struct dm_target_spec
*) outptr
;
978 spec
->sector_start
= ti
->begin
;
979 spec
->length
= ti
->len
;
980 strncpy(spec
->target_type
, ti
->type
->name
,
981 sizeof(spec
->target_type
));
983 outptr
+= sizeof(struct dm_target_spec
);
984 remaining
= len
- (outptr
- outbuf
);
985 if (remaining
<= 0) {
986 param
->flags
|= DM_BUFFER_FULL_FLAG
;
990 /* Get the status/table string from the target driver */
991 if (ti
->type
->status
) {
992 if (ti
->type
->status(ti
, type
, outptr
, remaining
)) {
993 param
->flags
|= DM_BUFFER_FULL_FLAG
;
999 outptr
+= strlen(outptr
) + 1;
1000 used
= param
->data_start
+ (outptr
- outbuf
);
1002 outptr
= align_ptr(outptr
);
1003 spec
->next
= outptr
- outbuf
;
1007 param
->data_size
= used
;
1009 param
->target_count
= num_targets
;
1013 * Wait for a device to report an event
1015 static int dev_wait(struct dm_ioctl
*param
, size_t param_size
)
1018 struct mapped_device
*md
;
1019 struct dm_table
*table
;
1021 md
= find_device(param
);
1026 * Wait for a notification event
1028 if (dm_wait_event(md
, param
->event_nr
)) {
1034 * The userland program is going to want to know what
1035 * changed to trigger the event, so we may as well tell
1036 * him and save an ioctl.
1038 r
= __dev_status(md
, param
);
1042 table
= dm_get_live_or_inactive_table(md
, param
);
1044 retrieve_status(table
, param
, param_size
);
1045 dm_table_put(table
);
1053 static inline fmode_t
get_mode(struct dm_ioctl
*param
)
1055 fmode_t mode
= FMODE_READ
| FMODE_WRITE
;
1057 if (param
->flags
& DM_READONLY_FLAG
)
1063 static int next_target(struct dm_target_spec
*last
, uint32_t next
, void *end
,
1064 struct dm_target_spec
**spec
, char **target_params
)
1066 *spec
= (struct dm_target_spec
*) ((unsigned char *) last
+ next
);
1067 *target_params
= (char *) (*spec
+ 1);
1069 if (*spec
< (last
+ 1))
1072 return invalid_str(*target_params
, end
);
1075 static int populate_table(struct dm_table
*table
,
1076 struct dm_ioctl
*param
, size_t param_size
)
1080 struct dm_target_spec
*spec
= (struct dm_target_spec
*) param
;
1081 uint32_t next
= param
->data_start
;
1082 void *end
= (void *) param
+ param_size
;
1083 char *target_params
;
1085 if (!param
->target_count
) {
1086 DMWARN("populate_table: no targets specified");
1090 for (i
= 0; i
< param
->target_count
; i
++) {
1092 r
= next_target(spec
, next
, end
, &spec
, &target_params
);
1094 DMWARN("unable to find target");
1098 r
= dm_table_add_target(table
, spec
->target_type
,
1099 (sector_t
) spec
->sector_start
,
1100 (sector_t
) spec
->length
,
1103 DMWARN("error adding target to table");
1110 r
= dm_table_set_type(table
);
1112 DMWARN("unable to set table type");
1116 return dm_table_complete(table
);
1119 static int table_prealloc_integrity(struct dm_table
*t
,
1120 struct mapped_device
*md
)
1122 struct list_head
*devices
= dm_table_get_devices(t
);
1123 struct dm_dev_internal
*dd
;
1125 list_for_each_entry(dd
, devices
, list
)
1126 if (bdev_get_integrity(dd
->dm_dev
.bdev
))
1127 return blk_integrity_register(dm_disk(md
), NULL
);
1132 static int table_load(struct dm_ioctl
*param
, size_t param_size
)
1135 struct hash_cell
*hc
;
1137 struct mapped_device
*md
;
1139 md
= find_device(param
);
1143 r
= dm_table_create(&t
, get_mode(param
), param
->target_count
, md
);
1147 r
= populate_table(t
, param
, param_size
);
1149 dm_table_destroy(t
);
1153 r
= table_prealloc_integrity(t
, md
);
1155 DMERR("%s: could not register integrity profile.",
1156 dm_device_name(md
));
1157 dm_table_destroy(t
);
1161 r
= dm_table_alloc_md_mempools(t
);
1163 DMWARN("unable to allocate mempools for this table");
1164 dm_table_destroy(t
);
1168 down_write(&_hash_lock
);
1169 hc
= dm_get_mdptr(md
);
1170 if (!hc
|| hc
->md
!= md
) {
1171 DMWARN("device has been removed from the dev hash table.");
1172 dm_table_destroy(t
);
1173 up_write(&_hash_lock
);
1179 dm_table_destroy(hc
->new_map
);
1181 up_write(&_hash_lock
);
1183 param
->flags
|= DM_INACTIVE_PRESENT_FLAG
;
1184 r
= __dev_status(md
, param
);
1192 static int table_clear(struct dm_ioctl
*param
, size_t param_size
)
1195 struct hash_cell
*hc
;
1196 struct mapped_device
*md
;
1198 down_write(&_hash_lock
);
1200 hc
= __find_device_hash_cell(param
);
1202 DMWARN("device doesn't appear to be in the dev hash table.");
1203 up_write(&_hash_lock
);
1208 dm_table_destroy(hc
->new_map
);
1212 param
->flags
&= ~DM_INACTIVE_PRESENT_FLAG
;
1214 r
= __dev_status(hc
->md
, param
);
1216 up_write(&_hash_lock
);
1222 * Retrieves a list of devices used by a particular dm device.
1224 static void retrieve_deps(struct dm_table
*table
,
1225 struct dm_ioctl
*param
, size_t param_size
)
1227 unsigned int count
= 0;
1228 struct list_head
*tmp
;
1230 struct dm_dev_internal
*dd
;
1231 struct dm_target_deps
*deps
;
1233 deps
= get_result_buffer(param
, param_size
, &len
);
1236 * Count the devices.
1238 list_for_each (tmp
, dm_table_get_devices(table
))
1242 * Check we have enough space.
1244 needed
= sizeof(*deps
) + (sizeof(*deps
->dev
) * count
);
1246 param
->flags
|= DM_BUFFER_FULL_FLAG
;
1251 * Fill in the devices.
1253 deps
->count
= count
;
1255 list_for_each_entry (dd
, dm_table_get_devices(table
), list
)
1256 deps
->dev
[count
++] = huge_encode_dev(dd
->dm_dev
.bdev
->bd_dev
);
1258 param
->data_size
= param
->data_start
+ needed
;
1261 static int table_deps(struct dm_ioctl
*param
, size_t param_size
)
1264 struct mapped_device
*md
;
1265 struct dm_table
*table
;
1267 md
= find_device(param
);
1271 r
= __dev_status(md
, param
);
1275 table
= dm_get_live_or_inactive_table(md
, param
);
1277 retrieve_deps(table
, param
, param_size
);
1278 dm_table_put(table
);
1287 * Return the status of a device as a text string for each
1290 static int table_status(struct dm_ioctl
*param
, size_t param_size
)
1293 struct mapped_device
*md
;
1294 struct dm_table
*table
;
1296 md
= find_device(param
);
1300 r
= __dev_status(md
, param
);
1304 table
= dm_get_live_or_inactive_table(md
, param
);
1306 retrieve_status(table
, param
, param_size
);
1307 dm_table_put(table
);
1316 * Pass a message to the target that's at the supplied device offset.
1318 static int target_message(struct dm_ioctl
*param
, size_t param_size
)
1322 struct mapped_device
*md
;
1323 struct dm_table
*table
;
1324 struct dm_target
*ti
;
1325 struct dm_target_msg
*tmsg
= (void *) param
+ param
->data_start
;
1327 md
= find_device(param
);
1331 r
= __dev_status(md
, param
);
1335 if (tmsg
< (struct dm_target_msg
*) param
->data
||
1336 invalid_str(tmsg
->message
, (void *) param
+ param_size
)) {
1337 DMWARN("Invalid target message parameters.");
1342 r
= dm_split_args(&argc
, &argv
, tmsg
->message
);
1344 DMWARN("Failed to split target message parameters");
1348 table
= dm_get_live_table(md
);
1352 if (dm_deleting_md(md
)) {
1357 ti
= dm_table_find_target(table
, tmsg
->sector
);
1358 if (!dm_target_is_valid(ti
)) {
1359 DMWARN("Target message sector outside device.");
1361 } else if (ti
->type
->message
)
1362 r
= ti
->type
->message(ti
, argc
, argv
);
1364 DMWARN("Target type does not support messages");
1369 dm_table_put(table
);
1373 param
->data_size
= 0;
1378 /*-----------------------------------------------------------------
1379 * Implementation of open/close/ioctl on the special char
1381 *---------------------------------------------------------------*/
1382 static ioctl_fn
lookup_ioctl(unsigned int cmd
)
1388 {DM_VERSION_CMD
, NULL
}, /* version is dealt with elsewhere */
1389 {DM_REMOVE_ALL_CMD
, remove_all
},
1390 {DM_LIST_DEVICES_CMD
, list_devices
},
1392 {DM_DEV_CREATE_CMD
, dev_create
},
1393 {DM_DEV_REMOVE_CMD
, dev_remove
},
1394 {DM_DEV_RENAME_CMD
, dev_rename
},
1395 {DM_DEV_SUSPEND_CMD
, dev_suspend
},
1396 {DM_DEV_STATUS_CMD
, dev_status
},
1397 {DM_DEV_WAIT_CMD
, dev_wait
},
1399 {DM_TABLE_LOAD_CMD
, table_load
},
1400 {DM_TABLE_CLEAR_CMD
, table_clear
},
1401 {DM_TABLE_DEPS_CMD
, table_deps
},
1402 {DM_TABLE_STATUS_CMD
, table_status
},
1404 {DM_LIST_VERSIONS_CMD
, list_versions
},
1406 {DM_TARGET_MSG_CMD
, target_message
},
1407 {DM_DEV_SET_GEOMETRY_CMD
, dev_set_geometry
}
1410 return (cmd
>= ARRAY_SIZE(_ioctls
)) ? NULL
: _ioctls
[cmd
].fn
;
1414 * As well as checking the version compatibility this always
1415 * copies the kernel interface version out.
1417 static int check_version(unsigned int cmd
, struct dm_ioctl __user
*user
)
1419 uint32_t version
[3];
1422 if (copy_from_user(version
, user
->version
, sizeof(version
)))
1425 if ((DM_VERSION_MAJOR
!= version
[0]) ||
1426 (DM_VERSION_MINOR
< version
[1])) {
1427 DMWARN("ioctl interface mismatch: "
1428 "kernel(%u.%u.%u), user(%u.%u.%u), cmd(%d)",
1429 DM_VERSION_MAJOR
, DM_VERSION_MINOR
,
1430 DM_VERSION_PATCHLEVEL
,
1431 version
[0], version
[1], version
[2], cmd
);
1436 * Fill in the kernel version.
1438 version
[0] = DM_VERSION_MAJOR
;
1439 version
[1] = DM_VERSION_MINOR
;
1440 version
[2] = DM_VERSION_PATCHLEVEL
;
1441 if (copy_to_user(user
->version
, version
, sizeof(version
)))
1447 static void free_params(struct dm_ioctl
*param
)
1452 static int copy_params(struct dm_ioctl __user
*user
, struct dm_ioctl
**param
)
1454 struct dm_ioctl tmp
, *dmi
;
1456 if (copy_from_user(&tmp
, user
, sizeof(tmp
) - sizeof(tmp
.data
)))
1459 if (tmp
.data_size
< (sizeof(tmp
) - sizeof(tmp
.data
)))
1462 dmi
= vmalloc(tmp
.data_size
);
1466 if (copy_from_user(dmi
, user
, tmp
.data_size
)) {
1475 static int validate_params(uint cmd
, struct dm_ioctl
*param
)
1477 /* Always clear this flag */
1478 param
->flags
&= ~DM_BUFFER_FULL_FLAG
;
1480 /* Ignores parameters */
1481 if (cmd
== DM_REMOVE_ALL_CMD
||
1482 cmd
== DM_LIST_DEVICES_CMD
||
1483 cmd
== DM_LIST_VERSIONS_CMD
)
1486 if ((cmd
== DM_DEV_CREATE_CMD
)) {
1487 if (!*param
->name
) {
1488 DMWARN("name not supplied when creating device");
1491 } else if ((*param
->uuid
&& *param
->name
)) {
1492 DMWARN("only supply one of name or uuid, cmd(%u)", cmd
);
1496 /* Ensure strings are terminated */
1497 param
->name
[DM_NAME_LEN
- 1] = '\0';
1498 param
->uuid
[DM_UUID_LEN
- 1] = '\0';
1503 static int ctl_ioctl(uint command
, struct dm_ioctl __user
*user
)
1507 struct dm_ioctl
*uninitialized_var(param
);
1511 /* only root can play with this */
1512 if (!capable(CAP_SYS_ADMIN
))
1515 if (_IOC_TYPE(command
) != DM_IOCTL
)
1518 cmd
= _IOC_NR(command
);
1521 * Check the interface version passed in. This also
1522 * writes out the kernel's interface version.
1524 r
= check_version(cmd
, user
);
1529 * Nothing more to do for the version command.
1531 if (cmd
== DM_VERSION_CMD
)
1534 fn
= lookup_ioctl(cmd
);
1536 DMWARN("dm_ctl_ioctl: unknown command 0x%x", command
);
1541 * Trying to avoid low memory issues when a device is
1544 current
->flags
|= PF_MEMALLOC
;
1547 * Copy the parameters into kernel space.
1549 r
= copy_params(user
, ¶m
);
1551 current
->flags
&= ~PF_MEMALLOC
;
1556 r
= validate_params(cmd
, param
);
1560 param_size
= param
->data_size
;
1561 param
->data_size
= sizeof(*param
);
1562 r
= fn(param
, param_size
);
1565 * Copy the results back to userland.
1567 if (!r
&& copy_to_user(user
, param
, param
->data_size
))
1575 static long dm_ctl_ioctl(struct file
*file
, uint command
, ulong u
)
1577 return (long)ctl_ioctl(command
, (struct dm_ioctl __user
*)u
);
1580 #ifdef CONFIG_COMPAT
1581 static long dm_compat_ctl_ioctl(struct file
*file
, uint command
, ulong u
)
1583 return (long)dm_ctl_ioctl(file
, command
, (ulong
) compat_ptr(u
));
1586 #define dm_compat_ctl_ioctl NULL
1589 static const struct file_operations _ctl_fops
= {
1590 .unlocked_ioctl
= dm_ctl_ioctl
,
1591 .compat_ioctl
= dm_compat_ctl_ioctl
,
1592 .owner
= THIS_MODULE
,
1595 static struct miscdevice _dm_misc
= {
1596 .minor
= MISC_DYNAMIC_MINOR
,
1598 .nodename
= "mapper/control",
1603 * Create misc character device and link to DM_DIR/control.
1605 int __init
dm_interface_init(void)
1613 r
= misc_register(&_dm_misc
);
1615 DMERR("misc_register failed for control device");
1620 DMINFO("%d.%d.%d%s initialised: %s", DM_VERSION_MAJOR
,
1621 DM_VERSION_MINOR
, DM_VERSION_PATCHLEVEL
, DM_VERSION_EXTRA
,
1626 void dm_interface_exit(void)
1628 if (misc_deregister(&_dm_misc
) < 0)
1629 DMERR("misc_deregister failed for control device");
1635 * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
1636 * @md: Pointer to mapped_device
1637 * @name: Buffer (size DM_NAME_LEN) for name
1638 * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
1640 int dm_copy_name_and_uuid(struct mapped_device
*md
, char *name
, char *uuid
)
1643 struct hash_cell
*hc
;
1648 mutex_lock(&dm_hash_cells_mutex
);
1649 hc
= dm_get_mdptr(md
);
1650 if (!hc
|| hc
->md
!= md
) {
1656 strcpy(name
, hc
->name
);
1658 strcpy(uuid
, hc
->uuid
? : "");
1661 mutex_unlock(&dm_hash_cells_mutex
);