* Drain all requests queued before DYING marking. Set DEAD flag to
* prevent that q->request_fn() gets invoked after draining finished.
*/
- if (q->mq_ops) {
- blk_mq_freeze_queue(q);
- spin_lock_irq(lock);
- } else {
- spin_lock_irq(lock);
+ blk_freeze_queue(q);
+ spin_lock_irq(lock);
+ if (!q->mq_ops)
__blk_drain_queue(q, true);
- }
queue_flag_set(QUEUE_FLAG_DEAD, q);
spin_unlock_irq(lock);
+ /* for synchronous bio-based driver finish in-flight integrity i/o */
+ blk_flush_integrity();
+
/* @q won't process any more request, flush async actions */
del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer);
blk_sync_queue(q);
if (q->mq_ops)
blk_mq_free_queue(q);
+ percpu_ref_exit(&q->q_usage_counter);
spin_lock_irq(lock);
if (q->queue_lock != &q->__queue_lock)
}
EXPORT_SYMBOL(blk_alloc_queue);
+int blk_queue_enter(struct request_queue *q, gfp_t gfp)
+{
+ while (true) {
+ int ret;
+
+ if (percpu_ref_tryget_live(&q->q_usage_counter))
+ return 0;
+
+ if (!(gfp & __GFP_WAIT))
+ return -EBUSY;
+
+ ret = wait_event_interruptible(q->mq_freeze_wq,
+ !atomic_read(&q->mq_freeze_depth) ||
+ blk_queue_dying(q));
+ if (blk_queue_dying(q))
+ return -ENODEV;
+ if (ret)
+ return ret;
+ }
+}
+
+void blk_queue_exit(struct request_queue *q)
+{
+ percpu_ref_put(&q->q_usage_counter);
+}
+
+static void blk_queue_usage_counter_release(struct percpu_ref *ref)
+{
+ struct request_queue *q =
+ container_of(ref, struct request_queue, q_usage_counter);
+
+ wake_up_all(&q->mq_freeze_wq);
+}
+
struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
{
struct request_queue *q;
init_waitqueue_head(&q->mq_freeze_wq);
- if (blkcg_init_queue(q))
+ /*
+ * Init percpu_ref in atomic mode so that it's faster to shutdown.
+ * See blk_register_queue() for details.
+ */
+ if (percpu_ref_init(&q->q_usage_counter,
+ blk_queue_usage_counter_release,
+ PERCPU_REF_INIT_ATOMIC, GFP_KERNEL))
goto fail_bdi;
+ if (blkcg_init_queue(q))
+ goto fail_ref;
+
return q;
+fail_ref:
+ percpu_ref_exit(&q->q_usage_counter);
fail_bdi:
bdi_destroy(&q->backing_dev_info);
fail_split:
}
EXPORT_SYMBOL(blk_init_queue_node);
-static void blk_queue_bio(struct request_queue *q, struct bio *bio);
+static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio);
struct request_queue *
blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn,
return ret;
}
+unsigned int blk_plug_queued_count(struct request_queue *q)
+{
+ struct blk_plug *plug;
+ struct request *rq;
+ struct list_head *plug_list;
+ unsigned int ret = 0;
+
+ plug = current->plug;
+ if (!plug)
+ goto out;
+
+ if (q->mq_ops)
+ plug_list = &plug->mq_list;
+ else
+ plug_list = &plug->list;
+
+ list_for_each_entry(rq, plug_list, queuelist) {
+ if (rq->q == q)
+ ret++;
+ }
+out:
+ return ret;
+}
+
void init_request_from_bio(struct request *req, struct bio *bio)
{
req->cmd_type = REQ_TYPE_FS;
blk_rq_bio_prep(req->q, req, bio);
}
-static void blk_queue_bio(struct request_queue *q, struct bio *bio)
+static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio)
{
const bool sync = !!(bio->bi_rw & REQ_SYNC);
struct blk_plug *plug;
if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
bio->bi_error = -EIO;
bio_endio(bio);
- return;
+ return BLK_QC_T_NONE;
}
if (bio->bi_rw & (REQ_FLUSH | REQ_FUA)) {
* Check if we can merge with the plugged list before grabbing
* any locks.
*/
- if (!blk_queue_nomerges(q) &&
- blk_attempt_plug_merge(q, bio, &request_count, NULL))
- return;
+ if (!blk_queue_nomerges(q)) {
+ if (blk_attempt_plug_merge(q, bio, &request_count, NULL))
+ return BLK_QC_T_NONE;
+ } else
+ request_count = blk_plug_queued_count(q);
spin_lock_irq(q->queue_lock);
out_unlock:
spin_unlock_irq(q->queue_lock);
}
+
+ return BLK_QC_T_NONE;
}
/*
* a lower device by calling into generic_make_request recursively, which
* means the bio should NOT be touched after the call to ->make_request_fn.
*/
-void generic_make_request(struct bio *bio)
+blk_qc_t generic_make_request(struct bio *bio)
{
struct bio_list bio_list_on_stack;
+ blk_qc_t ret = BLK_QC_T_NONE;
if (!generic_make_request_checks(bio))
- return;
+ goto out;
/*
* We only want one ->make_request_fn to be active at a time, else
*/
if (current->bio_list) {
bio_list_add(current->bio_list, bio);
- return;
+ goto out;
}
/* following loop may be a bit non-obvious, and so deserves some
do {
struct request_queue *q = bdev_get_queue(bio->bi_bdev);
- q->make_request_fn(q, bio);
+ if (likely(blk_queue_enter(q, __GFP_WAIT) == 0)) {
+
+ ret = q->make_request_fn(q, bio);
+
+ blk_queue_exit(q);
+
+ bio = bio_list_pop(current->bio_list);
+ } else {
+ struct bio *bio_next = bio_list_pop(current->bio_list);
- bio = bio_list_pop(current->bio_list);
+ bio_io_error(bio);
+ bio = bio_next;
+ }
} while (bio);
current->bio_list = NULL; /* deactivate */
+
+out:
+ return ret;
}
EXPORT_SYMBOL(generic_make_request);
* interfaces; @bio must be presetup and ready for I/O.
*
*/
-void submit_bio(int rw, struct bio *bio)
+blk_qc_t submit_bio(int rw, struct bio *bio)
{
bio->bi_rw |= rw;
}
}
- generic_make_request(bio);
+ return generic_make_request(bio);
}
EXPORT_SYMBOL(submit_bio);
}
EXPORT_SYMBOL(blk_finish_plug);
+bool blk_poll(struct request_queue *q, blk_qc_t cookie)
+{
+ struct blk_plug *plug;
+ long state;
+
+ if (!q->mq_ops || !q->mq_ops->poll || !blk_qc_t_valid(cookie) ||
+ !test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
+ return false;
+
+ plug = current->plug;
+ if (plug)
+ blk_flush_plug_list(plug, false);
+
+ state = current->state;
+ while (!need_resched()) {
+ unsigned int queue_num = blk_qc_t_to_queue_num(cookie);
+ struct blk_mq_hw_ctx *hctx = q->queue_hw_ctx[queue_num];
+ int ret;
+
+ hctx->poll_invoked++;
+
+ ret = q->mq_ops->poll(hctx, blk_qc_t_to_tag(cookie));
+ if (ret > 0) {
+ hctx->poll_success++;
+ set_current_state(TASK_RUNNING);
+ return true;
+ }
+
+ if (signal_pending_state(state, current))
+ set_current_state(TASK_RUNNING);
+
+ if (current->state == TASK_RUNNING)
+ return true;
+ if (ret < 0)
+ break;
+ cpu_relax();
+ }
+
+ return false;
+}
+
#ifdef CONFIG_PM
/**
* blk_pm_runtime_init - Block layer runtime PM initialization routine