Re: [PATCH v3 4/7] acpi, nfit: Use bus_dsm_mask for passthru

[Dan Williams]

On Thu, Jun 29, 2017 at 9:56 AM, Jerry Hoemann <jerry.hoemann@xxxxxxx> wrote:
> Populate bus_dsm_mask and use it to filter dsm calls that user can
> make through the pass thru interface.
>
> Signed-off-by: Jerry Hoemann <jerry.hoemann@xxxxxxx>
> ---
>  drivers/acpi/nfit/core.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> index b46fca2..971002b 100644
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -253,6 +253,8 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
>                 cmd_name = nvdimm_bus_cmd_name(cmd);
>                 cmd_mask = nd_desc->cmd_mask;
>                 dsm_mask = cmd_mask;
> +               if (cmd == ND_CMD_CALL)
> +                       dsm_mask = nd_desc->bus_dsm_mask;
>                 desc = nd_cmd_bus_desc(cmd);
>                 uuid = to_nfit_uuid(NFIT_DEV_BUS);
>                 handle = adev->handle;
> @@ -1624,6 +1626,9 @@ static void acpi_nfit_init_dsms(struct acpi_nfit_desc *acpi_desc)
>                 if (acpi_check_dsm(adev->handle, uuid, 1, 1ULL << i))
>                         set_bit(i, &nd_desc->cmd_mask);
>         set_bit(ND_CMD_CALL, &nd_desc->cmd_mask);
> +       for (i = 0; i < ND_CMD_CALL; i++)
> +               if (acpi_check_dsm(adev->handle, uuid, 1, 1ULL << i))
> +                       set_bit(i, &nd_desc->bus_dsm_mask);
>  }

This loop checks for function 6 which is specified as reserved. Lets
explicitly test for the known good function numbers with something
like this:

/* this should be private in drivers/acpi/nfit/nfit.h */
enum nfit_aux_cmds {
        NFIT_CMD_TRANSLATE_SPA = 5,
        NFIT_CMD_ARS_INJECT_SET = 7,
        NFIT_CMD_ARS_INJECT_CLEAR = 8,
        NFIT_CMD_ARS_INJECT_GET = 9,
};

bus_dsm_mask =
        (1 << ND_CMD_ARS_CAP) |
        (1 << ND_CMD_ARS_START) |
        (1 << ND_CMD_ARS_STATUS) |
        (1 << ND_CMD_CLEAR_ERROR) |
        (1 << NFIT_CMD_TRANSLATE_SPA) |
        (1 << NFIT_CMD_ARS_INJECT_SET) |
        (1 << NFIT_CMD_ARS_INJECT_CLEAR) |
        (1 << NFIT_CMD_ARS_INJECT_GET);

for_each_set_bit(i, &bus_dsm_mask...