bcache: fix crash with incomplete cache set
Change-Id: I6abde52afe917633480caaf4e2518f42a816d886
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index d2ebcf3..04f7bc2 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -477,9 +477,13 @@
* CACHE_SET_STOPPING always gets set first when we're closing down a cache set;
* we'll continue to run normally for awhile with CACHE_SET_STOPPING set (i.e.
* flushing dirty data).
+ *
+ * CACHE_SET_RUNNING means all cache devices have been registered and journal
+ * replay is complete.
*/
#define CACHE_SET_UNREGISTERING 0
#define CACHE_SET_STOPPING 1
+#define CACHE_SET_RUNNING 2
struct cache_set {
struct closure cl;
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 29dd1e8..72fbaf7 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1284,6 +1284,9 @@
if (test_bit(CACHE_SET_STOPPING, &c->flags))
return -EINTR;
+ if (!test_bit(CACHE_SET_RUNNING, &c->flags))
+ return -EPERM;
+
u = uuid_find_empty(c);
if (!u) {
pr_err("Can't create volume, no room for UUID");
@@ -1706,6 +1709,7 @@
flash_devs_run(c);
+ set_bit(CACHE_SET_RUNNING, &c->flags);
return;
err:
closure_sync(&cl);