1 files changed, 133 insertions, 0 deletions
diff --git a/libbcache/notify.c b/libbcache/notify.c
new file mode 100644
index 0000000..e9b5568
--- /dev/null
+++ b/libbcache/notify.c
@@ -0,0 +1,133 @@
+/*
+ * Code for sending uevent notifications to user-space.
+ *
+ * Copyright 2015 Datera, Inc.
+ */
+
+#include "bcache.h"
+#include "notify.h"
+
+#include <linux/kobject.h>
+
+#define notify_var(c, format, ...)					\
+({									\
+	int ret;							\
+	lockdep_assert_held(&(c)->uevent_lock);				\
+	ret = add_uevent_var(&(c)->uevent_env, format, ##__VA_ARGS__);	\
+	WARN_ON_ONCE(ret);						\
+})
+
+static void notify_get(struct cache_set *c)
+{
+	struct kobj_uevent_env *env = &c->uevent_env;
+
+	mutex_lock(&c->uevent_lock);
+	env->envp_idx = 0;
+	env->buflen = 0;
+
+	notify_var(c, "SET_UUID=%pU", c->disk_sb.user_uuid.b);
+}
+
+static void notify_get_cache(struct cache *ca)
+{
+	struct cache_set *c = ca->set;
+	char buf[BDEVNAME_SIZE];
+
+	notify_get(c);
+	notify_var(c, "UUID=%pU", ca->disk_sb.sb->disk_uuid.b);
+	notify_var(c, "BLOCKDEV=%s", bdevname(ca->disk_sb.bdev, buf));
+}
+
+static void notify_put(struct cache_set *c)
+{
+	struct kobj_uevent_env *env = &c->uevent_env;
+
+	env->envp[env->envp_idx] = NULL;
+	kobject_uevent_env(&c->kobj, KOBJ_CHANGE, env->envp);
+	mutex_unlock(&c->uevent_lock);
+}
+
+void bch_notify_cache_set_read_write(struct cache_set *c)
+{
+	notify_get(c);
+	notify_var(c, "STATE=active");
+	notify_put(c);
+}
+
+void bch_notify_cache_set_read_only(struct cache_set *c)
+{
+	notify_get(c);
+	notify_var(c, "STATE=readonly");
+	notify_put(c);
+}
+
+void bch_notify_cache_set_stopped(struct cache_set *c)
+{
+	notify_get(c);
+	notify_var(c, "STATE=stopped");
+	notify_put(c);
+}
+
+void bch_notify_cache_read_write(struct cache *ca)
+{
+	struct cache_set *c = ca->set;
+
+	notify_get_cache(ca);
+	notify_var(c, "STATE=active");
+	notify_put(c);
+}
+
+void bch_notify_cache_read_only(struct cache *ca)
+{
+	struct cache_set *c = ca->set;
+
+	notify_get_cache(ca);
+	notify_var(c, "STATE=readonly");
+	notify_put(c);
+}
+
+void bch_notify_cache_added(struct cache *ca)
+{
+	struct cache_set *c = ca->set;
+
+	notify_get_cache(ca);
+	notify_var(c, "STATE=removing");
+	notify_put(c);
+}
+
+void bch_notify_cache_removing(struct cache *ca)
+{
+	struct cache_set *c = ca->set;
+
+	notify_get_cache(ca);
+	notify_var(c, "STATE=removing");
+	notify_put(c);
+}
+
+void bch_notify_cache_remove_failed(struct cache *ca)
+{
+	struct cache_set *c = ca->set;
+
+	notify_get_cache(ca);
+	notify_var(c, "STATE=remove_failed");
+	notify_put(c);
+}
+
+void bch_notify_cache_removed(struct cache *ca)
+{
+	struct cache_set *c = ca->set;
+
+	notify_get_cache(ca);
+	notify_var(c, "STATE=removed");
+	notify_put(c);
+}
+
+void bch_notify_cache_error(struct cache *ca, bool fatal)
+{
+	struct cache_set *c = ca->set;
+
+	notify_get_cache(ca);
+	notify_var(c, "STATE=error");
+	notify_var(c, "FATAL=%d", fatal);
+	notify_put(c);
+}