From: "Luca Porzio (lporzio)" <lporzio@micron.com>
To: Yaniv Gardi <ygardi@codeaurora.org>,
        "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>,
        "vgoyal@redhat.com" <vgoyal@redhat.com>,
        "tj@kernel.org" <tj@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
CC: "linux-arm-msm@vger.kernel.org" <linux-arm-msm@vger.kernel.org>
Subject: RE: [PATCH v1] mmc: card: Adding support for sanitize in eMMC 4.5
Thread-Topic: [PATCH v1] mmc: card: Adding support for sanitize in eMMC 4.5
Thread-Index: AQHOEoOVvKTWzXh8tUGn859P256raJig6Mqg
Date: Mon, 11 Mar 2013 18:36:55 +0000
Message-ID: <26E7A31274623843B0E8CF86148BFE32B02F5779@NTXAVZMBX04.azit.micron.com>
References: <1361705927-10524-1-git-send-email-ygardi@codeaurora.org>
In-Reply-To: <1361705927-10524-1-git-send-email-ygardi@codeaurora.org>
Accept-Language: it-IT, en-US
Content-Language: en-US
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 8BIT
MIME-Version: 1.0
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 7061
Lines: 211

Hi Yaniv,

> -----Original Message-----
> From: linux-mmc-owner@vger.kernel.org [mailto:linux-mmc-
> owner@vger.kernel.org] On Behalf Of Yaniv Gardi
> Sent: Sunday, February 24, 2013 12:39 PM
> To: linux-mmc@vger.kernel.org; vgoyal@redhat.com; tj@kernel.org; linux-
> kernel@vger.kernel.org
> Cc: linux-arm-msm@vger.kernel.org; Yaniv Gardi
> Subject: [PATCH v1] mmc: card: Adding support for sanitize in eMMC 4.5
> 
> The sanitize support is added as a user-app ioctl call, and
> was removed from the block-device request, since its purpose is
> to be invoked not via File-System but by a user.
> This feature deletes the unmap memory region of the eMMC card,
> by writing to a specific register in the EXT_CSD.
> unmap region is the memory region that was previously deleted
> (by erase, trim or discard operation).
> In order to avoid timeout when sanitizing large-scale cards,
> the timeout for sanitize operation is 240 seconds.
> 
> Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
> 
> ---
>  drivers/mmc/card/block.c |   68 +++++++++++++++++++++++++++++++-----------
> ---
>  drivers/mmc/card/queue.c |    2 +-
>  include/linux/mmc/host.h |    1 +
>  3 files changed, 49 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
> index 21056b9..21bb8b4 100644
> --- a/drivers/mmc/card/block.c
> +++ b/drivers/mmc/card/block.c
> @@ -58,6 +58,8 @@ MODULE_ALIAS("mmc:block");
>  #define INAND_CMD38_ARG_SECTRIM1 0x81
>  #define INAND_CMD38_ARG_SECTRIM2 0x88
>  #define MMC_BLK_TIMEOUT_MS  (10 * 60 * 1000)        /* 10 minute timeout
> */
> +#define MMC_SANITIZE_REQ_TIMEOUT 240000

Though I would agree that 4 minutes is a reasonable sanitize time,
the sanitize command may also depend on card size.
As such I am not sure whether it can be regarded as a constant or
needs to be proportional to card size.

> +#define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16)
> 
>  static DEFINE_MUTEX(block_mutex);
> 
> @@ -394,6 +396,35 @@ static int ioctl_rpmb_card_status_poll(struct mmc_card
> *card, u32 *status,
>  	return err;
>  }
> 
> +static int ioctl_do_sanitize(struct mmc_card *card)
> +{
> +	int err;
> +
> +	if (!(mmc_can_sanitize(card) &&
> +	      (card->host->caps2 & MMC_CAP2_SANITIZE))) {
> +			pr_warn("%s: %s - SANITIZE is not supported\n",
> +				mmc_hostname(card->host), __func__);
> +			err = -EOPNOTSUPP;
> +			goto out;
> +	}
> +
> +	pr_debug("%s: %s - SANITIZE IN PROGRESS...\n",
> +		mmc_hostname(card->host), __func__);
> +
> +	err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
> +					EXT_CSD_SANITIZE_START, 1,
> +					MMC_SANITIZE_REQ_TIMEOUT);
> +
> +	if (err)
> +		pr_err("%s: %s - EXT_CSD_SANITIZE_START failed. err=%d\n",
> +		       mmc_hostname(card->host), __func__, err);
> +

In case of Sanitize timeout, the eMMC might go in an unclear state.
May I suggest to:
- issue an HPI before leaving thus bring the eMMC back into safe status
- report the 'sanitize not complete error' and let the user decide on 
  Whether he wants to re-issue (i.e. continue) the sanitize or just let 
  it go.

Thanks,
   Luca

> +	pr_debug("%s: %s - SANITIZE COMPLETED\n", mmc_hostname(card->host),
> +					     __func__);
> +out:
> +	return err;
> +}
> +
>  static int mmc_blk_ioctl_cmd(struct block_device *bdev,
>  	struct mmc_ioc_cmd __user *ic_ptr)
>  {
> @@ -496,6 +527,16 @@ static int mmc_blk_ioctl_cmd(struct block_device
> *bdev,
>  			goto cmd_rel_host;
>  	}
> 
> +	if (MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) {
> +		err = ioctl_do_sanitize(card);
> +
> +		if (err)
> +			pr_err("%s: ioctl_do_sanitize() failed. err = %d",
> +			       __func__, err);
> +
> +		goto cmd_rel_host;
> +	}
> +
>  	mmc_wait_for_req(card->host, &mrq);
> 
>  	if (cmd.error) {
> @@ -925,10 +966,10 @@ static int mmc_blk_issue_secdiscard_rq(struct
> mmc_queue *mq,
>  {
>  	struct mmc_blk_data *md = mq->data;
>  	struct mmc_card *card = md->queue.card;
> -	unsigned int from, nr, arg, trim_arg, erase_arg;
> +	unsigned int from, nr, arg;
>  	int err = 0, type = MMC_BLK_SECDISCARD;
> 
> -	if (!(mmc_can_secure_erase_trim(card) || mmc_can_sanitize(card))) {
> +	if (!(mmc_can_secure_erase_trim(card))) {
>  		err = -EOPNOTSUPP;
>  		goto out;
>  	}
> @@ -936,23 +977,11 @@ static int mmc_blk_issue_secdiscard_rq(struct
> mmc_queue *mq,
>  	from = blk_rq_pos(req);
>  	nr = blk_rq_sectors(req);
> 
> -	/* The sanitize operation is supported at v4.5 only */
> -	if (mmc_can_sanitize(card)) {
> -		erase_arg = MMC_ERASE_ARG;
> -		trim_arg = MMC_TRIM_ARG;
> -	} else {
> -		erase_arg = MMC_SECURE_ERASE_ARG;
> -		trim_arg = MMC_SECURE_TRIM1_ARG;
> -	}
> +	if (mmc_can_trim(card) && !mmc_erase_group_aligned(card, from, nr))
> +		arg = MMC_SECURE_TRIM1_ARG;
> +	else
> +		arg = MMC_SECURE_ERASE_ARG;
> 
> -	if (mmc_erase_group_aligned(card, from, nr))
> -		arg = erase_arg;
> -	else if (mmc_can_trim(card))
> -		arg = trim_arg;
> -	else {
> -		err = -EINVAL;
> -		goto out;
> -	}
>  retry:
>  	if (card->quirks & MMC_QUIRK_INAND_CMD38) {
>  		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
> @@ -988,9 +1017,6 @@ retry:
>  			goto out;
>  	}
> 
> -	if (mmc_can_sanitize(card))
> -		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
> -				 EXT_CSD_SANITIZE_START, 1, 0);
>  out_retry:
>  	if (err && !mmc_blk_reset(md, card->host, type))
>  		goto retry;
> diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
> index fadf52e..483f0e8 100644
> --- a/drivers/mmc/card/queue.c
> +++ b/drivers/mmc/card/queue.c
> @@ -148,7 +148,7 @@ static void mmc_queue_setup_discard(struct
> request_queue *q,
>  	/* granularity must not be greater than max. discard */
>  	if (card->pref_erase > max_discard)
>  		q->limits.discard_granularity = 0;
> -	if (mmc_can_secure_erase_trim(card) || mmc_can_sanitize(card))
> +	if (mmc_can_secure_erase_trim(card))
>  		queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD, q);
>  }
> 
> diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
> index 61a10c1..045e9f7 100644
> --- a/include/linux/mmc/host.h
> +++ b/include/linux/mmc/host.h
> @@ -258,6 +258,7 @@ struct mmc_host {
>  #define MMC_CAP2_HC_ERASE_SZ	(1 << 9)	/* High-capacity erase size */
>  #define MMC_CAP2_CD_ACTIVE_HIGH	(1 << 10)	/* Card-detect signal active
> high */
>  #define MMC_CAP2_RO_ACTIVE_HIGH	(1 << 11)	/* Write-protect signal active
> high */
> +#define MMC_CAP2_SANITIZE	(1 << 12)		/* Support Sanitize */
> 
>  	mmc_pm_flag_t		pm_caps;	/* supported pm features */
> 
> --
> 1.7.6
> --
> Sent by a consultant of the Qualcomm Innovation Center, Inc.
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/