Re: [External] : Re: [PATCH v2] mmc-utils: Add eMMC erase command support

[kimito . sakata]

On 3/30/2021 6:39 AM, Ulf Hansson wrote:
> On Wed, 24 Mar 2021 at 17:45, Bean Huo <huobean@xxxxxxxxx> wrote:
> > From: Kimito Sakata <kimito.sakata@xxxxxxxxxx>
> >
> > we have been using this erase feature for a while, but it is
> > still not merged into the upstream mmc-utils. Especially, for
> > the customer, every time when they update the mmc-utils, they
> > should re-install this patch again, let's try to make this
> > erase command upstreamed in the mmc-utils.
> >
> > Co-developed-by: Bean Huo <beanhuo@xxxxxxxxxx>
> > Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
> > Reviewed-by: Kenneth Gibbons <kenny.gibbons@xxxxxxxxxx>
> > ---
> >
> > Hi Ulf,
> > Please help us review this mmc-utils patch, and if agree, it is
> > possible to make it merged in the official mmc-utils.
> >
> > Changelog:
> >
> > V1--V2:
> >      1. refactor Kimito's original patch
> >      2. change to use MMC_IOC_MULTI_CMD
> >      3. add checkup if eMMC devie supports secure erase/trim
> >
> > ---
> >   mmc.c      |   8 ++++
> >   mmc.h      |  13 +++++-
> >   mmc_cmds.c | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> >   mmc_cmds.h |   1 +
> >   4 files changed, 156 insertions(+), 1 deletion(-)
> >
> > diff --git a/mmc.c b/mmc.c
> > index 50c9c9e..cb29a65 100644
> > --- a/mmc.c
> > +++ b/mmc.c
> > @@ -215,6 +215,14 @@ static struct Command commands[] = {
> >                  "Run Field Firmware Update with <image name> on <device>.\n",
> >            NULL
> >          },
> > +       { do_erase, -4,
> > +       "erase", "<type> " "<start address> " "<end address> " "<device>\n"
> > +               "Send Erase CMD38 with specific argument to the <device>\n\n"
> > +               "NOTE!: This will delete all user data in the specified region of the device\n"
> > +               "<type> must be: legacy | discard | secure-erase | "
> > +               "secure-trim1 | secure-trim2 | trim \n",
> > +       NULL
> > +       },
> >          { 0, 0, 0, 0 }
> >   };
> >
> > diff --git a/mmc.h b/mmc.h
> > index 648fb26..90b7fb5 100644
> > --- a/mmc.h
> > +++ b/mmc.h
> > @@ -34,7 +34,15 @@
> >   #define MMC_SET_WRITE_PROT     28    /* ac   [31:0] data addr   R1b */
> >   #define MMC_CLEAR_WRITE_PROT   29    /* ac   [31:0] data addr   R1b */
> >   #define MMC_SEND_WRITE_PROT_TYPE 31   /* ac   [31:0] data addr   R1  */
> > -
> > +#define MMC_ERASE_GROUP_START  35    /* ac   [31:0] data addr   R1  */
> > +#define MMC_ERASE_GROUP_END    36    /* ac   [31:0] data addr   R1  */
> > +#define MMC_ERASE              38    /* ac   [31] Secure request
> > +                                             [30:16] set to 0
> > +                                             [15] Force Garbage Collect request
> > +                                             [14:2] set to 0
> > +                                             [1] Discard Enable
> > +                                             [0] Identify Write Blocks for
> > +                                             Erase (or TRIM Enable)  R1b */
> >   /*
> >    * EXT_CSD fields
> >    */
> > @@ -61,6 +69,7 @@
> >   #define EXT_CSD_CACHE_SIZE_2           251
> >   #define EXT_CSD_CACHE_SIZE_1           250
> >   #define EXT_CSD_CACHE_SIZE_0           249
> > +#define EXT_CSD_SEC_FEATURE_SUPPORT    231
> >   #define EXT_CSD_BOOT_INFO              228     /* R/W */
> >   #define EXT_CSD_HC_ERASE_GRP_SIZE      224
> >   #define EXT_CSD_HC_WP_GRP_SIZE         221
> > @@ -177,6 +186,8 @@
> >   #define EXT_CSD_REV_V4_2               2
> >   #define EXT_CSD_REV_V4_1               1
> >   #define EXT_CSD_REV_V4_0               0
> > +#define EXT_CSD_SEC_GB_CL_EN           (1<<4)
> > +#define EXT_CSD_SEC_ER_EN              (1<<0)
> >
> >
> >   /* From kernel linux/mmc/core.h */
> > diff --git a/mmc_cmds.c b/mmc_cmds.c
> > index fb37189..17986e3 100644
> > --- a/mmc_cmds.c
> > +++ b/mmc_cmds.c
> > @@ -2435,6 +2435,141 @@ int do_cache_dis(int nargs, char **argv)
> >          return do_cache_ctrl(0, nargs, argv);
> >   }
> >
> > +static int erase(int dev_fd, __u32 argin, __u32 start, __u32 end)
> > +{
> > +#ifndef MMC_IOC_MULTI_CMD
> In kernel v4.4 we added the multi cmd support, which is quite some
> time ago. So, I think it's time to drop these ifdef hackary from the
> userland tool. At least, we shouldn't need it for new kinds of
> features that we add.
Ulf
Do you want us to take out the  MMC_IOC_MULTI_CMD ifdef and resubmit?
Kimito

> > +       fprintf(stderr, "mmc-utils has been compiled without MMC_IOC_MULTI_CMD"
> > +                       " support, needed by erase.\n");
> > +       return -ENOTSUP;
> > +#else
> > +       int ret = 0;
> > +       struct mmc_ioc_multi_cmd *multi_cmd;
> > +
> [...]
>
> Kind regards
> Uffe