| Message ID | 1344265951-22437-6-git-send-email-loic.pallardy-ext@stericsson.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Aug 6, 2012 at 8:42 PM, Loic Pallardy <loic.pallardy-ext@stericsson.com> wrote: > > RPMB partition is accessing though /dev/block/mmcXrpmb device > User callers can read and write entire data frame(s) as defined > by JEDEC Standard JESD84-A441, using standard IOCTL interface. > > Signed-off-by: Alex Macro <alex.macro@stericsson.com> > Signed-off-by: Loic Pallardy <loic.pallardy@stericsson.com> > Acked-by: Linus Walleij <linus.walleij@linaro.org> > Reviewed-by: Namjae Jeon <linkinjeon@gmail.com> > --- > drivers/mmc/card/block.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 64 insertions(+) > > diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c > index d8edb8d..a9e1f1f 100644 > --- a/drivers/mmc/card/block.c > +++ b/drivers/mmc/card/block.c > @@ -126,6 +126,10 @@ enum mmc_blk_status { > module_param(perdev_minors, int, 0444); > MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device"); > > +static inline int mmc_blk_part_switch(struct mmc_card *card, > + struct mmc_blk_data *md); > +static int get_card_status(struct mmc_card *card, u32 *status, int retries); > + > static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk) > { > struct mmc_blk_data *md; > @@ -357,6 +361,38 @@ out: > return ERR_PTR(err); > } > > +static int ioctl_rpmb_card_status_poll(struct mmc_card *card, u32 *status, > + u32 retries_max) > +{ > + int err; > + u32 retry_count = 0; > + > + if (!status || !retries_max) > + return -EINVAL; > + > + do { > + err = get_card_status(card, status, 5); > + if (err) > + break; > + > + if (!R1_STATUS(*status) && > + (R1_CURRENT_STATE(*status) != R1_STATE_PRG)) > + break; /* RPMB programming operation complete */ > + > + /* > + * Rechedule to give the MMC device a chance to continue > + * processing the previous command without being polled too > + * frequently. > + */ > + usleep_range(1000, 5000); > + } while (++retry_count < retries_max); > + > + if (retry_count == retries_max) > + err = -EPERM; > + > + return err; > +} > + > static int mmc_blk_ioctl_cmd(struct block_device *bdev, > struct mmc_ioc_cmd __user *ic_ptr) > { > @@ -368,6 +404,8 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, > struct mmc_request mrq = {NULL}; > struct scatterlist sg; > int err; > + int is_rpmb = false; > + u32 status = 0; > > /* > * The caller must have CAP_SYS_RAWIO, and must be calling this on the > @@ -387,6 +425,9 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, > goto cmd_err; > } > > + if (md->area_type & MMC_BLK_DATA_AREA_RPMB) > + is_rpmb = true; > + > card = md->queue.card; > if (IS_ERR(card)) { > err = PTR_ERR(card); > @@ -437,12 +478,23 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, > > mmc_claim_host(card->host); > > + err = mmc_blk_part_switch(card, md); > + if (err) > + goto cmd_rel_host; > + > if (idata->ic.is_acmd) { > err = mmc_app_cmd(card->host, card); > if (err) > goto cmd_rel_host; > } > > + if (is_rpmb) { > + err = mmc_set_blockcount(card, data.blocks, > + idata->ic.write_flag & (1 << 31)); > + if (err) > + goto cmd_rel_host; > + } > + > mmc_wait_for_req(card->host, &mrq); > > if (cmd.error) { > @@ -478,6 +530,18 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, > } > } > > + if (is_rpmb) { > + /* > + * Ensure RPMB command has completed by polling CMD13 > + * "Send Status". > + */ > + err = ioctl_rpmb_card_status_poll(card, &status, 5); > + if (err) > + dev_err(mmc_dev(card->host), > + "%s: Card Status=0x%08X, error %d\n", > + __func__, status, err); > + } > + > cmd_rel_host: > mmc_release_host(card->host); > > -- > 1.7.11.1 > > -- > 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 Hi, Any specific reason why the RPMB support is implemented using the IOCTL interface. Can this be done by the Kernel itself instead of being initiated by a user space application ? -- regards, Shashidhar Hiremath -- 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
> > > Hi, > Any specific reason why the RPMB support is implemented using the > IOCTL interface. Can this be done by the Kernel itself instead of > being initiated by a user space application ? > > -- > regards, > Shashidhar Hiremath > -- Hi, There are several reasons for that: - RPMB partition supports only few commands, it is not a "standard" partition - RPMB data access requests a dedicated data frame which contains MAC, write counter, address... - Only trusted/secured applications owns authentification key to calculate MAC (message authentification code) for each data frame. So implementing RPMB access in kernel will complexify the driver (link with security, data frame management...) and create vulnerability from security point of view. With this solution, kernel driver provides just a pipe between secured application and eMMC. Regards, Loic -- 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
On Fri, 2012-11-16 at 13:17 -0800, Krishna Konda wrote: > > > From: Loic Pallardy <loic.pallardy-ext@stericsson.com> > Date: Mon, Aug 6, 2012 at 8:12 AM > Subject: [PATCH v3 5/5] mmc: card: Add RPMB support in IOCTL interface > To: linux-mmc@vger.kernel.org, Chris Ball <cjb@laptop.org> > Cc: Linus Walleij <linus.walleij@linaro.org>, STEricsson_nomadik_linux > <STEricsson_nomadik_linux@list.st.com>, Ulf Hansson > <ulf.hansson@stericcson.com>, Loic Pallardy > <loic.pallardy-ext@stericsson.com>, Alex Macro > <alex.macro@stericsson.com>, Loic Pallardy > <loic.pallardy@stericsson.com> > > > RPMB partition is accessing though /dev/block/mmcXrpmb device > User callers can read and write entire data frame(s) as defined > by JEDEC Standard JESD84-A441, using standard IOCTL interface. > > Signed-off-by: Alex Macro <alex.macro@stericsson.com> > Signed-off-by: Loic Pallardy <loic.pallardy@stericsson.com> > Acked-by: Linus Walleij <linus.walleij@linaro.org> > Reviewed-by: Namjae Jeon <linkinjeon@gmail.com> Acked-by: Krishna Konda <kkonda@codeaurora.org>
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index d8edb8d..a9e1f1f 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -126,6 +126,10 @@ enum mmc_blk_status { module_param(perdev_minors, int, 0444); MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device"); +static inline int mmc_blk_part_switch(struct mmc_card *card, + struct mmc_blk_data *md); +static int get_card_status(struct mmc_card *card, u32 *status, int retries); + static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk) { struct mmc_blk_data *md; @@ -357,6 +361,38 @@ out: return ERR_PTR(err); } +static int ioctl_rpmb_card_status_poll(struct mmc_card *card, u32 *status, + u32 retries_max) +{ + int err; + u32 retry_count = 0; + + if (!status || !retries_max) + return -EINVAL; + + do { + err = get_card_status(card, status, 5); + if (err) + break; + + if (!R1_STATUS(*status) && + (R1_CURRENT_STATE(*status) != R1_STATE_PRG)) + break; /* RPMB programming operation complete */ + + /* + * Rechedule to give the MMC device a chance to continue + * processing the previous command without being polled too + * frequently. + */ + usleep_range(1000, 5000); + } while (++retry_count < retries_max); + + if (retry_count == retries_max) + err = -EPERM; + + return err; +} + static int mmc_blk_ioctl_cmd(struct block_device *bdev, struct mmc_ioc_cmd __user *ic_ptr) { @@ -368,6 +404,8 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, struct mmc_request mrq = {NULL}; struct scatterlist sg; int err; + int is_rpmb = false; + u32 status = 0; /* * The caller must have CAP_SYS_RAWIO, and must be calling this on the @@ -387,6 +425,9 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, goto cmd_err; } + if (md->area_type & MMC_BLK_DATA_AREA_RPMB) + is_rpmb = true; + card = md->queue.card; if (IS_ERR(card)) { err = PTR_ERR(card); @@ -437,12 +478,23 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, mmc_claim_host(card->host); + err = mmc_blk_part_switch(card, md); + if (err) + goto cmd_rel_host; + if (idata->ic.is_acmd) { err = mmc_app_cmd(card->host, card); if (err) goto cmd_rel_host; } + if (is_rpmb) { + err = mmc_set_blockcount(card, data.blocks, + idata->ic.write_flag & (1 << 31)); + if (err) + goto cmd_rel_host; + } + mmc_wait_for_req(card->host, &mrq); if (cmd.error) { @@ -478,6 +530,18 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev, } } + if (is_rpmb) { + /* + * Ensure RPMB command has completed by polling CMD13 + * "Send Status". + */ + err = ioctl_rpmb_card_status_poll(card, &status, 5); + if (err) + dev_err(mmc_dev(card->host), + "%s: Card Status=0x%08X, error %d\n", + __func__, status, err); + } + cmd_rel_host: mmc_release_host(card->host);