diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c index 6f2e565bccc5..444f8d88f1a8 100644 --- a/drivers/block/null_blk.c +++ b/drivers/block/null_blk.c @@ -117,6 +117,10 @@ static bool use_lightnvm; module_param(use_lightnvm, bool, S_IRUGO); MODULE_PARM_DESC(use_lightnvm, "Register as a LightNVM device"); +static bool blocking; +module_param(blocking, bool, S_IRUGO); +MODULE_PARM_DESC(blocking, "Register as a blocking blk-mq driver device"); + static int irqmode = NULL_IRQ_SOFTIRQ; static int null_set_irqmode(const char *str, const struct kernel_param *kp) @@ -357,6 +361,8 @@ static int null_queue_rq(struct blk_mq_hw_ctx *hctx, { struct nullb_cmd *cmd = blk_mq_rq_to_pdu(bd->rq); + might_sleep_if(hctx->flags & BLK_MQ_F_BLOCKING); + if (irqmode == NULL_IRQ_TIMER) { hrtimer_init(&cmd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); cmd->timer.function = null_cmd_timer_expired; @@ -724,6 +730,9 @@ static int null_add_dev(void) nullb->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; nullb->tag_set.driver_data = nullb; + if (blocking) + nullb->tag_set.flags |= BLK_MQ_F_BLOCKING; + rv = blk_mq_alloc_tag_set(&nullb->tag_set); if (rv) goto out_cleanup_queues;