dm: export name and uuid

This patch adds a function to obtain a copy of a mapped device's name and uuid.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Mike Anderson 2007-10-19 22:47:59 +01:00 committed by Alasdair G Kergon
parent aa5617c553
commit 96a1f7dba6
2 changed files with 33 additions and 0 deletions

View file

@ -1515,3 +1515,35 @@ void dm_interface_exit(void)
dm_hash_exit();
}
/**
* dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
* @md: Pointer to mapped_device
* @name: Buffer (size DM_NAME_LEN) for name
* @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
*/
int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
{
int r = 0;
struct hash_cell *hc;
if (!md)
return -ENXIO;
dm_get(md);
down_read(&_hash_lock);
hc = dm_get_mdptr(md);
if (!hc || hc->md != md) {
r = -ENXIO;
goto out;
}
strcpy(name, hc->name);
strcpy(uuid, hc->uuid ? : "");
out:
up_read(&_hash_lock);
dm_put(md);
return r;
}

View file

@ -188,6 +188,7 @@ int dm_wait_event(struct mapped_device *md, int event_nr);
* Info functions.
*/
const char *dm_device_name(struct mapped_device *md);
int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid);
struct gendisk *dm_disk(struct mapped_device *md);
int dm_suspended(struct mapped_device *md);
int dm_noflush_suspending(struct dm_target *ti);