diff --git a/drivers/mmc/host/mmc_hsq.c b/drivers/mmc/host/mmc_hsq.c index b90b2c97b6cf..a5e05ed0fda3 100644 --- a/drivers/mmc/host/mmc_hsq.c +++ b/drivers/mmc/host/mmc_hsq.c @@ -16,11 +16,20 @@ #define HSQ_NUM_SLOTS 64 #define HSQ_INVALID_TAG HSQ_NUM_SLOTS +static void mmc_hsq_retry_handler(struct work_struct *work) +{ + struct mmc_hsq *hsq = container_of(work, struct mmc_hsq, retry_work); + struct mmc_host *mmc = hsq->mmc; + + mmc->ops->request(mmc, hsq->mrq); +} + static void mmc_hsq_pump_requests(struct mmc_hsq *hsq) { struct mmc_host *mmc = hsq->mmc; struct hsq_slot *slot; unsigned long flags; + int ret = 0; spin_lock_irqsave(&hsq->lock, flags); @@ -42,7 +51,24 @@ static void mmc_hsq_pump_requests(struct mmc_hsq *hsq) spin_unlock_irqrestore(&hsq->lock, flags); - mmc->ops->request(mmc, hsq->mrq); + if (mmc->ops->request_atomic) + ret = mmc->ops->request_atomic(mmc, hsq->mrq); + else + mmc->ops->request(mmc, hsq->mrq); + + /* + * If returning BUSY from request_atomic(), which means the card + * may be busy now, and we should change to non-atomic context to + * try again for this unusual case, to avoid time-consuming operations + * in the atomic context. + * + * Note: we just give a warning for other error cases, since the host + * driver will handle them. + */ + if (ret == -EBUSY) + schedule_work(&hsq->retry_work); + else + WARN_ON_ONCE(ret); } static void mmc_hsq_update_next_tag(struct mmc_hsq *hsq, int remains) @@ -325,6 +351,7 @@ int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc) hsq->mmc->cqe_private = hsq; mmc->cqe_ops = &mmc_hsq_ops; + INIT_WORK(&hsq->retry_work, mmc_hsq_retry_handler); spin_lock_init(&hsq->lock); init_waitqueue_head(&hsq->wait_queue); diff --git a/drivers/mmc/host/mmc_hsq.h b/drivers/mmc/host/mmc_hsq.h index 18b9cf55925f..ffdd9cd172c3 100644 --- a/drivers/mmc/host/mmc_hsq.h +++ b/drivers/mmc/host/mmc_hsq.h @@ -12,6 +12,7 @@ struct mmc_hsq { wait_queue_head_t wait_queue; struct hsq_slot *slot; spinlock_t lock; + struct work_struct retry_work; int next_tag; int num_slots; diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index c318fb5b6a94..d4a50e5dc111 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -92,6 +92,9 @@ struct mmc_host_ops { int err); void (*pre_req)(struct mmc_host *host, struct mmc_request *req); void (*request)(struct mmc_host *host, struct mmc_request *req); + /* Submit one request to host in atomic context. */ + int (*request_atomic)(struct mmc_host *host, + struct mmc_request *req); /* * Avoid calling the next three functions too often or in a "fast