> If the device supports TRIM and indicates that it erases to zeros, we can use > it to support hardware offloading of REQ_OP_WRITE_ZEROES. > > Signed-off-by: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx> I agree that zero out is indeed a privet case of trim, as indicated by ERASED_MEM_CONT. Looks good to me. Thanks, Avri > --- > > Notes: > https://lore.kernel.org/lkml/20160303182146.GG9772@xxxxxxxxx/ seems > to agree > that BLKZEROOUT can use TRIM on eMMC. > > BLKDISCARD uses DISCARD when available so it can't be used to send > TRIM. > > If TRIM should not be used for BLKZEROOUT for some reason I guess the > only way > is to use MMC_IOC_MULTI_CMD like in this commit in mmc-utils but > that's a > rather low-level interface: > > https://git.kernel.org/pub/scm/utils/mmc/mmc- > utils.git/commit/?id=43282e80e174cc73b09b81a4d17cb3a7b4dc5cfc > > drivers/mmc/core/block.c | 26 ++++++++++++++++++++++---- > drivers/mmc/core/queue.c | 2 ++ > 2 files changed, 24 insertions(+), 4 deletions(-) > > diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index > 506dc900f5c7..0398b205a285 100644 > --- a/drivers/mmc/core/block.c > +++ b/drivers/mmc/core/block.c > @@ -126,6 +126,7 @@ struct mmc_blk_data { > #define MMC_BLK_DISCARD BIT(2) > #define MMC_BLK_SECDISCARD BIT(3) > #define MMC_BLK_CQE_RECOVERY BIT(4) > +#define MMC_BLK_TRIM BIT(5) > > /* > * Only set in main mmc_blk_data associated @@ -1090,12 +1091,13 > @@ static void mmc_blk_issue_drv_op(struct mmc_queue *mq, struct > request *req) > blk_mq_end_request(req, ret ? BLK_STS_IOERR : BLK_STS_OK); } > > -static void mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct > request *req) > +static void mmc_blk_issue_erase_rq(struct mmc_queue *mq, struct > request *req, > + int type, unsigned int erase_arg) > { > struct mmc_blk_data *md = mq->blkdata; > struct mmc_card *card = md->queue.card; > unsigned int from, nr; > - int err = 0, type = MMC_BLK_DISCARD; > + int err = 0; > blk_status_t status = BLK_STS_OK; > > if (!mmc_can_erase(card)) { > @@ -1111,13 +1113,13 @@ static void mmc_blk_issue_discard_rq(struct > mmc_queue *mq, struct request *req) > if (card->quirks & MMC_QUIRK_INAND_CMD38) { > err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, > INAND_CMD38_ARG_EXT_CSD, > - card->erase_arg == MMC_TRIM_ARG ? > + erase_arg == MMC_TRIM_ARG ? > INAND_CMD38_ARG_TRIM : > INAND_CMD38_ARG_ERASE, > card->ext_csd.generic_cmd6_time); > } > if (!err) > - err = mmc_erase(card, from, nr, card->erase_arg); > + err = mmc_erase(card, from, nr, erase_arg); > } while (err == -EIO && !mmc_blk_reset(md, card->host, type)); > if (err) > status = BLK_STS_IOERR; > @@ -1127,6 +1129,19 @@ static void mmc_blk_issue_discard_rq(struct > mmc_queue *mq, struct request *req) > blk_mq_end_request(req, status); } > > +static void mmc_blk_issue_trim_rq(struct mmc_queue *mq, struct request > +*req) { > + mmc_blk_issue_erase_rq(mq, req, MMC_BLK_TRIM, MMC_TRIM_ARG); > } > + > +static void mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct > +request *req) { > + struct mmc_blk_data *md = mq->blkdata; > + struct mmc_card *card = md->queue.card; > + > + mmc_blk_issue_erase_rq(mq, req, MMC_BLK_DISCARD, > +card->erase_arg); } > + > static void mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq, > struct request *req) { @@ -2327,6 +2342,9 @@ enum > mmc_issued mmc_blk_mq_issue_rq(struct mmc_queue *mq, struct request > *req) > case REQ_OP_SECURE_ERASE: > mmc_blk_issue_secdiscard_rq(mq, req); > break; > + case REQ_OP_WRITE_ZEROES: > + mmc_blk_issue_trim_rq(mq, req); > + break; > case REQ_OP_FLUSH: > mmc_blk_issue_flush(mq, req); > break; > diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c index > c69b2d9df6f1..bbe2ea829ea7 100644 > --- a/drivers/mmc/core/queue.c > +++ b/drivers/mmc/core/queue.c > @@ -191,6 +191,8 @@ static void mmc_queue_setup_discard(struct > request_queue *q, > q->limits.discard_granularity = SECTOR_SIZE; > if (mmc_can_secure_erase_trim(card)) > blk_queue_flag_set(QUEUE_FLAG_SECERASE, q); > + if (mmc_can_trim(card) && card->erased_byte == 0) > + blk_queue_max_write_zeroes_sectors(q, max_discard); > } > > static unsigned short mmc_get_max_segments(struct mmc_host *host) > -- > 2.34.1