> On 20/04/21 8:53 am, Avri Altman wrote:
> > The cache may be flushed to the nonvolatile storage by writing to
> > FLUSH_CACHE byte (EXT_CSD byte [32]). When in command queueing mode,
> the
> > cache may be flushed by issuing a CMDQ_TASK_ DEV_MGMT (CMD48) with a
> > FLUSH_CACHE op-code. Either way, verify that The cache function is
> > turned ON before doing so.
> >
> > fixes: 1e8e55b67030 (mmc: block: Add CQE support)
> >
> > Reported-by: Brendan Peter <bpeter@xxxxxxxx>
> > Tested-by: Brendan Peter <bpeter@xxxxxxxx>
> > Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
> > ---
> > drivers/mmc/core/block.c | 7 +++++++
> > drivers/mmc/core/mmc.c | 2 +-
> > drivers/mmc/core/mmc_ops.h | 5 +++++
> > 3 files changed, 13 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
> > index 8bfd4d95b386..5b6501fc9fb7 100644
> > --- a/drivers/mmc/core/block.c
> > +++ b/drivers/mmc/core/block.c
> > @@ -1476,6 +1476,11 @@ static int mmc_blk_cqe_issue_flush(struct
> mmc_queue *mq, struct request *req)
> > struct mmc_queue_req *mqrq = req_to_mmc_queue_req(req);
> > struct mmc_request *mrq = mmc_blk_cqe_prep_dcmd(mqrq, req);
> >
> > + if (mmc_card_mmc(mq->card) && !mmc_flush_allowed(mq->card)) {
> > + blk_mq_end_request(req, BLK_STS_OK);
> > + return -EPERM;
> > + }
> > +
> > mrq->cmd->opcode = MMC_SWITCH;
> > mrq->cmd->arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
> > (EXT_CSD_FLUSH_CACHE << 16) |
> > @@ -2226,6 +2231,8 @@ enum mmc_issued mmc_blk_mq_issue_rq(struct
> mmc_queue *mq, struct request *req)
> > switch (req_op(req)) {
> > case REQ_OP_FLUSH:
> > ret = mmc_blk_cqe_issue_flush(mq, req);
> > + if (ret == -EPERM)
> > + return MMC_REQ_FINISHED;
>
> Using an error code for this case seems a little fragile.
>
> How about something like:
>
> case REQ_OP_FLUSH:
> if (mmc_blk_cache_disabled(mq->card)) {
> blk_mq_end_request(req, BLK_STS_OK);
> return MMC_REQ_FINISHED;
> }
> ret = mmc_blk_cqe_issue_flush(mq, req);
>
>
> static bool mmc_blk_cache_disabled(struct mmc_card *card)
> {
> return mmc_card_mmc(mq->card) && !mmc_flush_allowed(card);
> }
Done.
Thanks,
Avri
