+int
+spa_vdev_initialize(spa_t *spa, uint64_t guid, uint64_t cmd_type)
+{
+ /*
+ * We hold the namespace lock through the whole function
+ * to prevent any changes to the pool while we're starting or
+ * stopping initialization. The config and state locks are held so that
+ * we can properly assess the vdev state before we commit to
+ * the initializing operation.
+ */
+ mutex_enter(&spa_namespace_lock);
+ spa_config_enter(spa, SCL_CONFIG | SCL_STATE, FTAG, RW_READER);
+
+ /* Look up vdev and ensure it's a leaf. */
+ vdev_t *vd = spa_lookup_by_guid(spa, guid, B_FALSE);
+ if (vd == NULL || vd->vdev_detached) {
+ spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
+ mutex_exit(&spa_namespace_lock);
+ return (SET_ERROR(ENODEV));
+ } else if (!vd->vdev_ops->vdev_op_leaf || !vdev_is_concrete(vd)) {
+ spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
+ mutex_exit(&spa_namespace_lock);
+ return (SET_ERROR(EINVAL));
+ } else if (!vdev_writeable(vd)) {
+ spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
+ mutex_exit(&spa_namespace_lock);
+ return (SET_ERROR(EROFS));
+ }
+ mutex_enter(&vd->vdev_initialize_lock);
+ spa_config_exit(spa, SCL_CONFIG | SCL_STATE, FTAG);
+
+ /*
+ * When we activate an initialize action we check to see
+ * if the vdev_initialize_thread is NULL. We do this instead
+ * of using the vdev_initialize_state since there might be
+ * a previous initialization process which has completed but
+ * the thread is not exited.
+ */
+ if (cmd_type == POOL_INITIALIZE_DO &&
+ (vd->vdev_initialize_thread != NULL ||
+ vd->vdev_top->vdev_removing)) {
+ mutex_exit(&vd->vdev_initialize_lock);
+ mutex_exit(&spa_namespace_lock);
+ return (SET_ERROR(EBUSY));
+ } else if (cmd_type == POOL_INITIALIZE_CANCEL &&
+ (vd->vdev_initialize_state != VDEV_INITIALIZE_ACTIVE &&
+ vd->vdev_initialize_state != VDEV_INITIALIZE_SUSPENDED)) {
+ mutex_exit(&vd->vdev_initialize_lock);
+ mutex_exit(&spa_namespace_lock);
+ return (SET_ERROR(ESRCH));
+ } else if (cmd_type == POOL_INITIALIZE_SUSPEND &&
+ vd->vdev_initialize_state != VDEV_INITIALIZE_ACTIVE) {
+ mutex_exit(&vd->vdev_initialize_lock);
+ mutex_exit(&spa_namespace_lock);
+ return (SET_ERROR(ESRCH));
+ }
+
+ switch (cmd_type) {
+ case POOL_INITIALIZE_DO:
+ vdev_initialize(vd);
+ break;
+ case POOL_INITIALIZE_CANCEL:
+ vdev_initialize_stop(vd, VDEV_INITIALIZE_CANCELED);
+ break;
+ case POOL_INITIALIZE_SUSPEND:
+ vdev_initialize_stop(vd, VDEV_INITIALIZE_SUSPENDED);
+ break;
+ default:
+ panic("invalid cmd_type %llu", (unsigned long long)cmd_type);
+ }
+ mutex_exit(&vd->vdev_initialize_lock);
+
+ /* Sync out the initializing state */
+ txg_wait_synced(spa->spa_dsl_pool, 0);
+ mutex_exit(&spa_namespace_lock);
+
+ return (0);
+}
+
+