*/
static int register_snapshot(struct dm_snapshot *snap)
{
- struct origin *o;
+ struct origin *o, *new_o;
struct block_device *bdev = snap->origin->bdev;
+ new_o = kmalloc(sizeof(*new_o), GFP_KERNEL);
+ if (!new_o)
+ return -ENOMEM;
+
down_write(&_origins_lock);
o = __lookup_origin(bdev);
- if (!o) {
+ if (o)
+ kfree(new_o);
+ else {
/* New origin */
- o = kmalloc(sizeof(*o), GFP_KERNEL);
- if (!o) {
- up_write(&_origins_lock);
- return -ENOMEM;
- }
+ o = new_o;
/* Initialise the struct */
INIT_LIST_HEAD(&o->snapshots);
struct dm_snap_pending_exception *pe = mempool_alloc(s->pending_pool,
GFP_NOIO);
+ atomic_inc(&s->pending_exceptions_count);
pe->snap = s;
return pe;
static void free_pending_exception(struct dm_snap_pending_exception *pe)
{
- mempool_free(pe, pe->snap->pending_pool);
+ struct dm_snapshot *s = pe->snap;
+
+ mempool_free(pe, s->pending_pool);
+ smp_mb__before_atomic_dec();
+ atomic_dec(&s->pending_exceptions_count);
}
static void insert_completed_exception(struct dm_snapshot *s,
s->valid = 1;
s->active = 0;
- s->last_percent = 0;
+ atomic_set(&s->pending_exceptions_count, 0);
init_rwsem(&s->lock);
spin_lock_init(&s->pe_lock);
s->ti = ti;
/* After this returns there can be no new kcopyd jobs. */
unregister_snapshot(s);
+ while (atomic_read(&s->pending_exceptions_count))
+ yield();
+ /*
+ * Ensure instructions in mempool_destroy aren't reordered
+ * before atomic_read.
+ */
+ smp_mb();
+
#ifdef CONFIG_DM_DEBUG
for (i = 0; i < DM_TRACKED_CHUNK_HASH_SIZE; i++)
BUG_ON(!hlist_empty(&s->tracked_chunk_hash[i]));
* the bios for the original write to the origin.
*/
if (primary_pe &&
- atomic_dec_and_test(&primary_pe->ref_count))
+ atomic_dec_and_test(&primary_pe->ref_count)) {
origin_bios = bio_list_get(&primary_pe->origin_bios);
+ free_pending_exception(primary_pe);
+ }
/*
* Free the pe if it's not linked to an origin write or if
if (!primary_pe || primary_pe != pe)
free_pending_exception(pe);
- /*
- * Free the primary pe if nothing references it.
- */
- if (primary_pe && !atomic_read(&primary_pe->ref_count))
- free_pending_exception(primary_pe);
-
return origin_bios;
}