On 19 June 2011 23:17, Per Forlin <per.forlin@xxxxxxxxxx> wrote:
> Change mmc_blk_issue_rw_rq() to become asynchronous.
> The execution flow looks like this:
> The mmc-queue calls issue_rw_rq(), which sends the request
> to the host and returns back to the mmc-queue. The mmc-queue calls
> issue_rw_rq() again with a new request. This new request is prepared,
> in isuue_rw_rq(), then it waits for the active request to complete before
> pushing it to the host. When to mmc-queue is empty it will call
> isuue_rw_rq() with req=NULL to finish off the active request
> without starting a new request.
>
> Signed-off-by: Per Forlin <per.forlin@xxxxxxxxxx>
> ---
> drivers/mmc/card/block.c | 121 +++++++++++++++++++++++++++++++++-------------
> drivers/mmc/card/queue.c | 17 +++++--
> drivers/mmc/card/queue.h | 1 +
> 3 files changed, 101 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> index 6a84a75..66db77a 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -108,6 +108,7 @@ static DEFINE_MUTEX(open_lock);
>
> enum mmc_blk_status {
> MMC_BLK_SUCCESS = 0,
> + MMC_BLK_PARTIAL,
> MMC_BLK_RETRY,
> MMC_BLK_DATA_ERR,
> MMC_BLK_CMD_ERR,
> @@ -668,14 +669,16 @@ static inline void mmc_apply_rel_rw(struct mmc_blk_request *brq,
> }
> }
>
> -static enum mmc_blk_status mmc_blk_err_check(struct mmc_blk_request *brq,
> - struct request *req,
> - struct mmc_card *card,
> - struct mmc_blk_data *md)
> +static int mmc_blk_err_check(struct mmc_card *card,
> + struct mmc_async_req *areq)
> {
> struct mmc_command cmd;
> u32 status = 0;
> enum mmc_blk_status ret = MMC_BLK_SUCCESS;
> + struct mmc_queue_req *mq_mrq = container_of(areq, struct mmc_queue_req,
> + mmc_active);
> + struct mmc_blk_request *brq = &mq_mrq->brq;
> + struct request *req = mq_mrq->req;
>
> /*
> * Check for errors here, but don't jump to cmd_err
> @@ -770,7 +773,11 @@ static enum mmc_blk_status mmc_blk_err_check(struct mmc_blk_request *brq,
> else
> ret = MMC_BLK_DATA_ERR;
> }
> -out:
> +
> + if (ret == MMC_BLK_SUCCESS &&
> + blk_rq_bytes(req) != brq->data.bytes_xfered)
> + ret = MMC_BLK_PARTIAL;
> + out:
> return ret;
> }
>
> @@ -901,27 +908,59 @@ static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
> brq->data.sg_len = i;
> }
>
> + mqrq->mmc_active.mrq = &brq->mrq;
> + mqrq->mmc_active.err_check = mmc_blk_err_check;
> +
> mmc_queue_bounce_pre(mqrq);
> }
>
> -static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
> +static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
> {
> struct mmc_blk_data *md = mq->data;
> struct mmc_card *card = md->queue.card;
> - struct mmc_blk_request *brq = &mq->mqrq_cur->brq;
> - int ret = 1, disable_multi = 0;
> + struct mmc_blk_request *brq;
> + int ret = 1;
> + int disable_multi = 0;
> enum mmc_blk_status status;
> + struct mmc_queue_req *mq_rq;
> + struct request *req;
> + struct mmc_async_req *areq;
> +
> + if (!rqc && !mq->mqrq_prev->req)
> + goto out;
>
> do {
> - mmc_blk_rw_rq_prep(mq->mqrq_cur, card, disable_multi, mq);
> - mmc_wait_for_req(card->host, &brq->mrq);
> + if (rqc) {
> + mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
> + areq = &mq->mqrq_cur->mmc_active;
> + } else
> + areq = NULL;
> + areq = mmc_start_req(card->host, areq, (int *) &status);
> + if (!areq)
> + goto out;
>
> - mmc_queue_bounce_post(mq->mqrq_cur);
> - status = mmc_blk_err_check(brq, req, card, md);
> + mq_rq = container_of(areq, struct mmc_queue_req, mmc_active);
> + brq = &mq_rq->brq;
> + req = mq_rq->req;
> + mmc_queue_bounce_post(mq_rq);
>
> switch (status) {
> - case MMC_BLK_CMD_ERR:
> - goto cmd_err;
> + case MMC_BLK_SUCCESS:
> + case MMC_BLK_PARTIAL:
> + /*
> + * A block was successfully transferred.
> + */
> + spin_lock_irq(&md->lock);
> + ret = __blk_end_request(req, 0,
> + brq->data.bytes_xfered);
> + spin_unlock_irq(&md->lock);
> + if (status == MMC_BLK_SUCCESS && ret) {
> + /* If this happen it is a bug */
> + printk(KERN_ERR "%s BUG rq_tot %d d_xfer %d\n",
> + __func__, blk_rq_bytes(req),
> + brq->data.bytes_xfered);
> + goto cmd_err;
> + }
> break;
> case MMC_BLK_RETRY:
> disable_multi = 1;
> @@ -934,36 +973,41 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
> * read a single sector.
> */
> spin_lock_irq(&md->lock);
> - ret = __blk_end_request(req, -EIO,
> - brq->data.blksz);
> + ret = __blk_end_request(req, -EIO, brq->data.blksz);
> spin_unlock_irq(&md->lock);
> -
> + if (!ret)
> + goto start_new_req;
> break;
> - case MMC_BLK_SUCCESS:
> + case MMC_BLK_CMD_ERR:
> + ret = 1;
> + goto cmd_err;
> + break;
> + }
> +
> + if (ret) {
> /*
> - * A block was successfully transferred.
> + * In case of a none complete request
> + * prepare it again and resend.
> */
> - spin_lock_irq(&md->lock);
> - ret = __blk_end_request(req, 0, brq->data.bytes_xfered);
> - spin_unlock_irq(&md->lock);
> - break;
> + mmc_blk_rw_rq_prep(mq_rq, card, disable_multi, mq);
> + mmc_start_req(card->host, &mq_rq->mmc_active, NULL);
> }
> } while (ret);
>
> return 1;
> -
> + out:
> + return 0;
> cmd_err:
> - /*
> - * If this is an SD card and we're writing, we can first
> - * mark the known good sectors as ok.
> - *
> + /*
> + * If this is an SD card and we're writing, we can first
> + * mark the known good sectors as ok.
> + *
> * If the card is not SD, we can still ok written sectors
> * as reported by the controller (which might be less than
> * the real number of written sectors, but never more).
> */
> if (mmc_card_sd(card)) {
> u32 blocks;
> -
> blocks = mmc_sd_num_wr_blocks(card);
> if (blocks != (u32)-1) {
> spin_lock_irq(&md->lock);
> @@ -981,6 +1025,12 @@ static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
> ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
> spin_unlock_irq(&md->lock);
>
> + start_new_req:
> + if (rqc) {
> + mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
> + mmc_start_req(card->host, &mq->mqrq_cur->mmc_active, NULL);
> + }
> +
> return 0;
> }
>
> @@ -990,26 +1040,31 @@ static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
> struct mmc_blk_data *md = mq->data;
> struct mmc_card *card = md->queue.card;
>
> - mmc_claim_host(card->host);
> + if (req && !mq->mqrq_prev->req)
> + /* claim host only for the first request */
> + mmc_claim_host(card->host);
> +
> ret = mmc_blk_part_switch(card, md);
> if (ret) {
> ret = 0;
> goto out;
> }
>
> - if (req->cmd_flags & REQ_DISCARD) {
> + if (req && req->cmd_flags & REQ_DISCARD) {
/* complete ongoing async transfer before issuing discard */
if (card->host->areq)
mmc_blk_issue_rw_rq(mq, NULL);
prevent mmc_erase to run in parallel to mmc async request.
/Per
--
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