dm exception store: introduce registry
Move exception stores into a registry.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c
index b558176..51bc4a7 100644
--- a/drivers/md/dm-snap-transient.c
+++ b/drivers/md/dm-snap-transient.c
@@ -23,7 +23,7 @@
sector_t next_free;
};
-static void transient_destroy(struct dm_exception_store *store)
+static void transient_dtr(struct dm_exception_store *store)
{
kfree(store->context);
}
@@ -67,17 +67,11 @@
*denominator = get_dev_size(store->snap->cow->bdev);
}
-int dm_create_transient(struct dm_exception_store *store)
+static int transient_ctr(struct dm_exception_store *store,
+ unsigned argc, char **argv)
{
struct transient_c *tc;
- store->type.dtr = transient_destroy;
- store->type.read_metadata = transient_read_metadata;
- store->type.prepare_exception = transient_prepare_exception;
- store->type.commit_exception = transient_commit_exception;
- store->type.drop_snapshot = NULL;
- store->type.fraction_full = transient_fraction_full;
-
tc = kmalloc(sizeof(struct transient_c), GFP_KERNEL);
if (!tc)
return -ENOMEM;
@@ -88,11 +82,62 @@
return 0;
}
+static int transient_status(struct dm_exception_store *store,
+ status_type_t status, char *result,
+ unsigned maxlen)
+{
+ int sz = 0;
+
+ return sz;
+}
+
+static struct dm_exception_store_type _transient_type = {
+ .name = "transient",
+ .module = THIS_MODULE,
+ .ctr = transient_ctr,
+ .dtr = transient_dtr,
+ .read_metadata = transient_read_metadata,
+ .prepare_exception = transient_prepare_exception,
+ .commit_exception = transient_commit_exception,
+ .fraction_full = transient_fraction_full,
+ .status = transient_status,
+};
+
+static struct dm_exception_store_type _transient_compat_type = {
+ .name = "N",
+ .module = THIS_MODULE,
+ .ctr = transient_ctr,
+ .dtr = transient_dtr,
+ .read_metadata = transient_read_metadata,
+ .prepare_exception = transient_prepare_exception,
+ .commit_exception = transient_commit_exception,
+ .fraction_full = transient_fraction_full,
+ .status = transient_status,
+};
+
int dm_transient_snapshot_init(void)
{
- return 0;
+ int r;
+
+ r = dm_exception_store_type_register(&_transient_type);
+ if (r) {
+ DMWARN("Unable to register transient exception store type");
+ return r;
+ }
+
+ r = dm_exception_store_type_register(&_transient_compat_type);
+ if (r) {
+ DMWARN("Unable to register old-style transient "
+ "exception store type");
+ dm_exception_store_type_unregister(&_transient_type);
+ return r;
+ }
+
+ return r;
}
void dm_transient_snapshot_exit(void)
{
+ dm_exception_store_type_unregister(&_transient_type);
+ dm_exception_store_type_unregister(&_transient_compat_type);
}