Commit f7b6fc32 authored by Vincent Whitchurch's avatar Vincent Whitchurch Committed by Ulf Hansson
Browse files

mmc: core: Support zeroout using TRIM for eMMC 



If an eMMC card supports TRIM and indicates that it erases to zeros, we can
use it to support hardware offloading of REQ_OP_WRITE_ZEROES, so let's add
support for this.

Signed-off-by: default avatarVincent Whitchurch <vincent.whitchurch@axis.com>
Reviewed-by: default avatarAvri Altman <Avri.Altman@wdc.com>
Link: https://lore.kernel.org/r/20220429152118.3617303-1-vincent.whitchurch@axis.com


Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 0c9ee5ba

drivers/mmc/core/block.c

+22 −4
Original line number Diff line number Diff line
@@ -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
@@ -1092,12 +1093,13 @@ 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)) {
@@ -1113,13 +1115,13 @@ 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;
@@ -1129,6 +1131,19 @@ 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)

{
@@ -2329,6 +2344,9 @@ 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;

drivers/mmc/core/queue.c

+2 −0
Original line number Diff line number Diff line
@@ -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)