From mboxrd@z Thu Jan 1 00:00:00 1970 From: akpm@linux-foundation.org Subject: [patch 16/24] mmc_block: add discard support Date: Wed, 11 Aug 2010 14:17:47 -0700 Message-ID: <201008112117.o7BLHmxf015019@imap1.linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:33533 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751392Ab0HKVSP (ORCPT ); Wed, 11 Aug 2010 17:18:15 -0400 Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: torvalds@linux-foundation.org Cc: akpm@linux-foundation.org, adrian.hunter@nokia.com, axboe@kernel.dk, bengardiner@nanometrics.ca, hch@lst.de, kmpark@infradead.org, linux-mmc@vger.kernel.org, madhu.cr@ti.com From: Adrian Hunter Enable MMC to service discard requests. In the case of SD and MMC cards that do not support trim, discards become erases. In the case of cards (MMC) that only allow erases in multiples of erase group size, round to the nearest completely discarded erase group. Signed-off-by: Adrian Hunter Acked-by: Jens Axboe Cc: Kyungmin Park Cc: Madhusudhan Chikkature Cc: Christoph Hellwig Cc: Ben Gardiner Cc: Signed-off-by: Andrew Morton --- drivers/mmc/card/block.c | 42 ++++++++++++++++++++++++++++++++++++- drivers/mmc/card/queue.c | 16 ++++++++++++-- 2 files changed, 55 insertions(+), 3 deletions(-) diff -puN drivers/mmc/card/block.c~mmc_block-add-discard-support drivers/mmc/card/block.c --- a/drivers/mmc/card/block.c~mmc_block-add-discard-support +++ a/drivers/mmc/card/block.c @@ -247,7 +247,40 @@ static u32 get_card_status(struct mmc_ca return cmd.resp[0]; } -static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req) +static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req) +{ + struct mmc_blk_data *md = mq->data; + struct mmc_card *card = md->queue.card; + unsigned int from, nr, arg; + int err = 0; + + mmc_claim_host(card->host); + + if (!mmc_can_erase(card)) { + err = -EOPNOTSUPP; + goto out; + } + + from = blk_rq_pos(req); + nr = blk_rq_sectors(req); + + if (mmc_can_trim(card)) + arg = MMC_TRIM_ARG; + else + arg = MMC_ERASE_ARG; + + err = mmc_erase(card, from, nr, arg); +out: + spin_lock_irq(&md->lock); + __blk_end_request(req, err, blk_rq_bytes(req)); + spin_unlock_irq(&md->lock); + + mmc_release_host(card->host); + + return err ? 0 : 1; +} + +static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req) { struct mmc_blk_data *md = mq->data; struct mmc_card *card = md->queue.card; @@ -475,6 +508,13 @@ static int mmc_blk_issue_rq(struct mmc_q return 0; } +static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req) +{ + if (req->cmd_flags & REQ_DISCARD) + return mmc_blk_issue_discard_rq(mq, req); + else + return mmc_blk_issue_rw_rq(mq, req); +} static inline int mmc_blk_readonly(struct mmc_card *card) { diff -puN drivers/mmc/card/queue.c~mmc_block-add-discard-support drivers/mmc/card/queue.c --- a/drivers/mmc/card/queue.c~mmc_block-add-discard-support +++ a/drivers/mmc/card/queue.c @@ -30,9 +30,9 @@ static int mmc_prep_request(struct request_queue *q, struct request *req) { /* - * We only like normal block requests. + * We only like normal block requests and discards. */ - if (req->cmd_type != REQ_TYPE_FS) { + if (req->cmd_type != REQ_TYPE_FS && !(req->cmd_flags & REQ_DISCARD)) { blk_dump_rq_flags(req, "MMC bad request"); return BLKPREP_KILL; } @@ -130,6 +130,18 @@ int mmc_init_queue(struct mmc_queue *mq, blk_queue_prep_rq(mq->queue, mmc_prep_request); blk_queue_ordered(mq->queue, QUEUE_ORDERED_DRAIN); queue_flag_set_unlocked(QUEUE_FLAG_NONROT, mq->queue); + if (mmc_can_erase(card)) { + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mq->queue); + mq->queue->limits.max_discard_sectors = UINT_MAX; + if (card->erased_byte == 0) + mq->queue->limits.discard_zeroes_data = 1; + if (!mmc_can_trim(card) && is_power_of_2(card->erase_size)) { + mq->queue->limits.discard_granularity = + card->erase_size << 9; + mq->queue->limits.discard_alignment = + card->erase_size << 9; + } + } #ifdef CONFIG_MMC_BLOCK_BOUNCE if (host->max_hw_segs == 1) { _