* change as blkcg is disabled and enabled higher up in the hierarchy, a wb
* is tested for blkcg after lookup and removed from index on mismatch so
* that a new wb for the combination can be created.
+ *
+ * Each bdi_writeback that is not embedded into the backing_dev_info must hold
+ * a reference to the parent backing_dev_info. See cgwb_create() for details.
*/
struct bdi_writeback {
struct backing_dev_info *bdi; /* our parent bdi */
memset(wb, 0, sizeof(*wb));
- if (wb != &bdi->wb)
- bdi_get(bdi);
wb->bdi = bdi;
wb->last_old_flush = jiffies;
INIT_LIST_HEAD(&wb->b_dirty);
err = fprop_local_init_percpu(&wb->completions, gfp);
if (err)
- goto out_put_bdi;
+ return err;
for (i = 0; i < NR_WB_STAT_ITEMS; i++) {
err = percpu_counter_init(&wb->stat[i], 0, gfp);
while (i--)
percpu_counter_destroy(&wb->stat[i]);
fprop_local_destroy_percpu(&wb->completions);
-out_put_bdi:
- if (wb != &bdi->wb)
- bdi_put(bdi);
return err;
}
percpu_counter_destroy(&wb->stat[i]);
fprop_local_destroy_percpu(&wb->completions);
- if (wb != &wb->bdi->wb)
- bdi_put(wb->bdi);
}
#ifdef CONFIG_CGROUP_WRITEBACK
struct bdi_writeback *wb = container_of(work, struct bdi_writeback,
release_work);
struct blkcg *blkcg = css_to_blkcg(wb->blkcg_css);
+ struct backing_dev_info *bdi = wb->bdi;
mutex_lock(&wb->bdi->cgwb_release_mutex);
wb_shutdown(wb);
percpu_ref_exit(&wb->refcnt);
wb_exit(wb);
+ bdi_put(bdi);
WARN_ON_ONCE(!list_empty(&wb->b_attached));
kfree_rcu(wb, rcu);
}
INIT_LIST_HEAD(&wb->b_attached);
INIT_WORK(&wb->release_work, cgwb_release_workfn);
set_bit(WB_registered, &wb->state);
+ bdi_get(bdi);
/*
* The root wb determines the registered state of the whole bdi and
goto out_put;
err_fprop_exit:
+ bdi_put(bdi);
fprop_local_destroy_percpu(&wb->memcg_completions);
err_ref_exit:
percpu_ref_exit(&wb->refcnt);