aboutsummaryrefslogtreecommitdiff
path: root/drivers
diff options
context:
space:
mode:
authorJoe Thornber <ejt@redhat.com>2013-05-10 14:37:19 +0100
committerAlasdair G Kergon <agk@redhat.com>2013-05-10 14:37:19 +0100
commit1921c56d95c4ac92b359ad44ffbc1e9a36060b29 (patch)
tree86d0e844addb338759bf9bae0c8253c7dcb34921 /drivers
parent5d0db96d13a4e2cd22b52494fb19ce5a9c8b8d90 (diff)
downloadlinux-linaro-stable-1921c56d95c4ac92b359ad44ffbc1e9a36060b29.tar.gz
dm persistent data: support space map resizing
Support extending a dm persistent data metadata space map. The extend itself is implemented by switching back to the boostrap allocator and pointing to the new space. The extra bitmap indexes are then allocated from the new space, and finally we switch back to the proper space map ops and tweak the reference counts. Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/md/persistent-data/dm-space-map-metadata.c38
1 files changed, 32 insertions, 6 deletions
diff --git a/drivers/md/persistent-data/dm-space-map-metadata.c b/drivers/md/persistent-data/dm-space-map-metadata.c
index d87a30a243db..51ca9edef444 100644
--- a/drivers/md/persistent-data/dm-space-map-metadata.c
+++ b/drivers/md/persistent-data/dm-space-map-metadata.c
@@ -144,12 +144,6 @@ static void sm_metadata_destroy(struct dm_space_map *sm)
kfree(smm);
}
-static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
-{
- DMERR("doesn't support extend");
- return -EINVAL;
-}
-
static int sm_metadata_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
{
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
@@ -382,6 +376,8 @@ static int sm_metadata_copy_root(struct dm_space_map *sm, void *where_le, size_t
return 0;
}
+static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks);
+
static struct dm_space_map ops = {
.destroy = sm_metadata_destroy,
.extend = sm_metadata_extend,
@@ -522,6 +518,36 @@ static struct dm_space_map bootstrap_ops = {
/*----------------------------------------------------------------*/
+static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
+{
+ int r, i;
+ enum allocation_event ev;
+ struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
+ dm_block_t old_len = smm->ll.nr_blocks;
+
+ /*
+ * Flick into a mode where all blocks get allocated in the new area.
+ */
+ smm->begin = old_len;
+ memcpy(&smm->sm, &bootstrap_ops, sizeof(smm->sm));
+
+ /*
+ * Extend.
+ */
+ r = sm_ll_extend(&smm->ll, extra_blocks);
+
+ /*
+ * Switch back to normal behaviour.
+ */
+ memcpy(&smm->sm, &ops, sizeof(smm->sm));
+ for (i = old_len; !r && i < smm->begin; i++)
+ r = sm_ll_inc(&smm->ll, i, &ev);
+
+ return r;
+}
+
+/*----------------------------------------------------------------*/
+
struct dm_space_map *dm_sm_metadata_init(void)
{
struct sm_metadata *smm;