On 14 November 2018 at 17:02, Christoph Hellwig <hch@xxxxxx> wrote:
> mmc uses the block layer struct request pointer to indirect their own
> lock to the mmc_queue structure, given that the original lock isn't
> reachable outside of block.c. Add a lock pointer to struct mmc_queue
> instead and stop overriding the block layer lock which protects fields
> entirely separate from the mmc use.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> drivers/mmc/core/block.c | 22 ++++++++++------------
> drivers/mmc/core/queue.c | 26 +++++++++++++-------------
> drivers/mmc/core/queue.h | 1 +
> 3 files changed, 24 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
> index 27606e1382e5..70ec465beb69 100644
> --- a/drivers/mmc/core/block.c
> +++ b/drivers/mmc/core/block.c
> @@ -1483,7 +1483,7 @@ static void mmc_blk_cqe_complete_rq(struct mmc_queue *mq, struct request *req)
> blk_mq_end_request(req, BLK_STS_OK);
> }
>
> - spin_lock_irqsave(q->queue_lock, flags);
> + spin_lock_irqsave(mq->lock, flags);
>
> mq->in_flight[mmc_issue_type(mq, req)] -= 1;
>
> @@ -1491,7 +1491,7 @@ static void mmc_blk_cqe_complete_rq(struct mmc_queue *mq, struct request *req)
>
> mmc_cqe_check_busy(mq);
>
> - spin_unlock_irqrestore(q->queue_lock, flags);
> + spin_unlock_irqrestore(mq->lock, flags);
>
> if (!mq->cqe_busy)
> blk_mq_run_hw_queues(q, true);
> @@ -1988,17 +1988,16 @@ static void mmc_blk_mq_poll_completion(struct mmc_queue *mq,
>
> static void mmc_blk_mq_dec_in_flight(struct mmc_queue *mq, struct request *req)
> {
> - struct request_queue *q = req->q;
> unsigned long flags;
> bool put_card;
>
> - spin_lock_irqsave(q->queue_lock, flags);
> + spin_lock_irqsave(mq->lock, flags);
>
> mq->in_flight[mmc_issue_type(mq, req)] -= 1;
>
> put_card = (mmc_tot_in_flight(mq) == 0);
>
> - spin_unlock_irqrestore(q->queue_lock, flags);
> + spin_unlock_irqrestore(mq->lock, flags);
>
> if (put_card)
> mmc_put_card(mq->card, &mq->ctx);
> @@ -2094,11 +2093,11 @@ static void mmc_blk_mq_req_done(struct mmc_request *mrq)
> * request does not need to wait (although it does need to
> * complete complete_req first).
> */
> - spin_lock_irqsave(q->queue_lock, flags);
> + spin_lock_irqsave(mq->lock, flags);
> mq->complete_req = req;
> mq->rw_wait = false;
> waiting = mq->waiting;
> - spin_unlock_irqrestore(q->queue_lock, flags);
> + spin_unlock_irqrestore(mq->lock, flags);
>
> /*
> * If 'waiting' then the waiting task will complete this
> @@ -2117,10 +2116,10 @@ static void mmc_blk_mq_req_done(struct mmc_request *mrq)
> /* Take the recovery path for errors or urgent background operations */
> if (mmc_blk_rq_error(&mqrq->brq) ||
> mmc_blk_urgent_bkops_needed(mq, mqrq)) {
> - spin_lock_irqsave(q->queue_lock, flags);
> + spin_lock_irqsave(mq->lock, flags);
> mq->recovery_needed = true;
> mq->recovery_req = req;
> - spin_unlock_irqrestore(q->queue_lock, flags);
> + spin_unlock_irqrestore(mq->lock, flags);
> wake_up(&mq->wait);
> schedule_work(&mq->recovery_work);
> return;
> @@ -2136,7 +2135,6 @@ static void mmc_blk_mq_req_done(struct mmc_request *mrq)
>
> static bool mmc_blk_rw_wait_cond(struct mmc_queue *mq, int *err)
> {
> - struct request_queue *q = mq->queue;
> unsigned long flags;
> bool done;
>
> @@ -2144,7 +2142,7 @@ static bool mmc_blk_rw_wait_cond(struct mmc_queue *mq, int *err)
> * Wait while there is another request in progress, but not if recovery
> * is needed. Also indicate whether there is a request waiting to start.
> */
> - spin_lock_irqsave(q->queue_lock, flags);
> + spin_lock_irqsave(mq->lock, flags);
> if (mq->recovery_needed) {
> *err = -EBUSY;
> done = true;
> @@ -2152,7 +2150,7 @@ static bool mmc_blk_rw_wait_cond(struct mmc_queue *mq, int *err)
> done = !mq->rw_wait;
> }
> mq->waiting = !done;
> - spin_unlock_irqrestore(q->queue_lock, flags);
> + spin_unlock_irqrestore(mq->lock, flags);
>
> return done;
> }
> diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
> index 37617fb1f9de..ac6a5245275a 100644
> --- a/drivers/mmc/core/queue.c
> +++ b/drivers/mmc/core/queue.c
> @@ -89,9 +89,9 @@ void mmc_cqe_recovery_notifier(struct mmc_request *mrq)
> struct mmc_queue *mq = q->queuedata;
> unsigned long flags;
>
> - spin_lock_irqsave(q->queue_lock, flags);
> + spin_lock_irqsave(mq->lock, flags);
> __mmc_cqe_recovery_notifier(mq);
> - spin_unlock_irqrestore(q->queue_lock, flags);
> + spin_unlock_irqrestore(mq->lock, flags);
> }
>
> static enum blk_eh_timer_return mmc_cqe_timed_out(struct request *req)
> @@ -128,14 +128,14 @@ static enum blk_eh_timer_return mmc_mq_timed_out(struct request *req,
> unsigned long flags;
> int ret;
>
> - spin_lock_irqsave(q->queue_lock, flags);
> + spin_lock_irqsave(mq->lock, flags);
>
> if (mq->recovery_needed || !mq->use_cqe)
> ret = BLK_EH_RESET_TIMER;
> else
> ret = mmc_cqe_timed_out(req);
>
> - spin_unlock_irqrestore(q->queue_lock, flags);
> + spin_unlock_irqrestore(mq->lock, flags);
>
> return ret;
> }
> @@ -157,9 +157,9 @@ static void mmc_mq_recovery_handler(struct work_struct *work)
>
> mq->in_recovery = false;
>
> - spin_lock_irq(q->queue_lock);
> + spin_lock_irq(mq->lock);
> mq->recovery_needed = false;
> - spin_unlock_irq(q->queue_lock);
> + spin_unlock_irq(mq->lock);
>
> mmc_put_card(mq->card, &mq->ctx);
>
> @@ -258,10 +258,10 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
>
> issue_type = mmc_issue_type(mq, req);
>
> - spin_lock_irq(q->queue_lock);
> + spin_lock_irq(mq->lock);
>
> if (mq->recovery_needed || mq->busy) {
> - spin_unlock_irq(q->queue_lock);
> + spin_unlock_irq(mq->lock);
> return BLK_STS_RESOURCE;
> }
>
> @@ -269,7 +269,7 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
> case MMC_ISSUE_DCMD:
> if (mmc_cqe_dcmd_busy(mq)) {
> mq->cqe_busy |= MMC_CQE_DCMD_BUSY;
> - spin_unlock_irq(q->queue_lock);
> + spin_unlock_irq(mq->lock);
> return BLK_STS_RESOURCE;
> }
> break;
> @@ -294,7 +294,7 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
> get_card = (mmc_tot_in_flight(mq) == 1);
> cqe_retune_ok = (mmc_cqe_qcnt(mq) == 1);
>
> - spin_unlock_irq(q->queue_lock);
> + spin_unlock_irq(mq->lock);
>
> if (!(req->rq_flags & RQF_DONTPREP)) {
> req_to_mmc_queue_req(req)->retries = 0;
> @@ -328,12 +328,12 @@ static blk_status_t mmc_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
> if (issued != MMC_REQ_STARTED) {
> bool put_card = false;
>
> - spin_lock_irq(q->queue_lock);
> + spin_lock_irq(mq->lock);
> mq->in_flight[issue_type] -= 1;
> if (mmc_tot_in_flight(mq) == 0)
> put_card = true;
> mq->busy = false;
> - spin_unlock_irq(q->queue_lock);
> + spin_unlock_irq(mq->lock);
> if (put_card)
> mmc_put_card(card, &mq->ctx);
> } else {
> @@ -397,6 +397,7 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
> int ret;
>
> mq->card = card;
> + mq->lock = lock;
Unless I am mistaken, it seems like the "lock" can also be removed as
an in-parameter to mmc_init_queue() - and instead do the
spin_lock_init() in here.
Moreover, that means we should drop the "lock" from the struct
mmc_blk_data and instead move it to struct mmc_queue (rather than
having a pointer to it.)
> mq->use_cqe = host->cqe_enabled;
>
> memset(&mq->tag_set, 0, sizeof(mq->tag_set));
> @@ -427,7 +428,6 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card,
> goto free_tag_set;
> }
>
> - mq->queue->queue_lock = lock;
> mq->queue->queuedata = mq;
> blk_queue_rq_timeout(mq->queue, 60 * HZ);
>
> diff --git a/drivers/mmc/core/queue.h b/drivers/mmc/core/queue.h
> index 29218e12900d..5421f1542e71 100644
> --- a/drivers/mmc/core/queue.h
> +++ b/drivers/mmc/core/queue.h
> @@ -73,6 +73,7 @@ struct mmc_queue_req {
>
> struct mmc_queue {
> struct mmc_card *card;
> + spinlock_t *lock;
> struct mmc_ctx ctx;
> struct blk_mq_tag_set tag_set;
> struct mmc_blk_data *blkdata;
> --
> 2.19.1
>
Kind regards
Uffe
