static int wb_init(struct bdi_writeback *wb, struct backing_dev_info *bdi,
int blkcg_id, gfp_t gfp)
{
int i, err;
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);
INIT_LIST_HEAD(&wb->b_io);
INIT_LIST_HEAD(&wb->b_more_io);
INIT_LIST_HEAD(&wb->b_dirty_time);
spin_lock_init(&wb->list_lock);
wb->bw_time_stamp = jiffies;
wb->balanced_dirty_ratelimit = INIT_BW;
wb->dirty_ratelimit = INIT_BW;
wb->write_bandwidth = INIT_BW;
wb->avg_write_bandwidth = INIT_BW;
spin_lock_init(&wb->work_lock);
INIT_LIST_HEAD(&wb->work_list);
INIT_DELAYED_WORK(&wb->dwork, wb_workfn);
wb->dirty_sleep = jiffies;
wb->congested = wb_congested_get_create(bdi, blkcg_id, gfp);
if (!wb->congested) {
err = -ENOMEM;
goto out_put_bdi;
}
err = fprop_local_init_percpu(&wb->completions, gfp);
if (err)
goto out_put_cong;
for (i = 0; i < NR_WB_STAT_ITEMS; i++) {
err = percpu_counter_init(&wb->stat[i], 0, gfp);
if (err)
goto out_destroy_stat;
}
return 0;
out_destroy_stat:
while (i--)
percpu_counter_destroy(&wb->stat[i]);
fprop_local_destroy_percpu(&wb->completions);
out_put_cong:
wb_congested_put(wb->congested);
out_put_bdi:
if (wb != &bdi->wb)
bdi_put(bdi);
return err;
}
static void wb_exit(struct bdi_writeback *wb)
{
int i;
WARN_ON(delayed_work_pending(&wb->dwork));
for (i = 0; i < NR_WB_STAT_ITEMS; i++)
percpu_counter_destroy(&wb->stat[i]);
fprop_local_destroy_percpu(&wb->completions);
wb_congested_put(wb->congested);
if (wb != &wb->bdi->wb)
bdi_put(wb->bdi);
}
/**
* blk_release_queue: - release a &struct request_queue when it is no longer needed
* @kobj: the kobj belonging to the request queue to be released
*
* Description:
* blk_release_queue is the pair to blk_init_queue() or
* blk_queue_make_request(). It should be called when a request queue is
* being released; typically when a block device is being de-registered.
* Currently, its primary task it to free all the &struct request
* structures that were allocated to the queue and the queue itself.
*
* Note:
* The low level driver must have finished any outstanding requests first
* via blk_cleanup_queue().
**/
static void blk_release_queue(struct kobject *kobj)
{
struct request_queue *q =
container_of(kobj, struct request_queue, kobj);
if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags))
blk_stat_remove_callback(q, q->poll_cb);
blk_stat_free_callback(q->poll_cb);
bdi_put(q->backing_dev_info);
blkcg_exit_queue(q);
if (q->elevator) {
ioc_clear_queue(q);
elevator_exit(q, q->elevator);
}
blk_free_queue_stats(q->stats);
blk_exit_rl(&q->root_rl);
if (q->queue_tags)
__blk_queue_free_tags(q);
if (!q->mq_ops) {
if (q->exit_rq_fn)
q->exit_rq_fn(q, q->fq->flush_rq);
blk_free_flush_queue(q->fq);
} else {
blk_mq_release(q);
}
blk_trace_shutdown(q);
if (q->mq_ops)
blk_mq_debugfs_unregister(q);
if (q->bio_split)
bioset_free(q->bio_split);
ida_simple_remove(&blk_queue_ida, q->id);
call_rcu(&q->rcu_head, blk_free_queue_rcu);
}
