Re: [PATCH v3 11/15] firmware: qcom: qseecom: convert to using the TZ allocator

[Bartosz Golaszewski]

On Wed, Oct 11, 2023 at 12:49 AM Andrew Halaney <ahalaney@xxxxxxxxxx> wrote:
>
> On Mon, Oct 09, 2023 at 05:34:23PM +0200, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> >
> > Drop the DMA mapping operations from qcom_scm_qseecom_app_send() and
> > convert all users of it in the qseecom module to using the TZ allocator
> > for creating SCM call buffers. Together with using the cleanup macros,
> > it has the added benefit of a significant code shrink. As this is
> > largely a module separate from the SCM driver, let's use a separate
> > memory pool.
> >
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
>
> <snip>
>
> > @@ -567,20 +529,14 @@ static efi_status_t qsee_uefi_get_next_variable(struct qcuefi_client *qcuefi,
> >               return EFI_INVALID_PARAMETER;
> >
> >       status = qcom_qseecom_app_send(qcuefi->client, req_data, req_size, rsp_data, rsp_size);
> > -     if (status) {
> > -             efi_status = EFI_DEVICE_ERROR;
> > -             goto out_free;
> > -     }
> > +     if (status)
> > +             return EFI_DEVICE_ERROR;
> >
> > -     if (rsp_data->command_id != QSEE_CMD_UEFI_GET_NEXT_VARIABLE) {
> > -             efi_status = EFI_DEVICE_ERROR;
> > -             goto out_free;
> > -     }
> > +     if (rsp_data->command_id != QSEE_CMD_UEFI_GET_NEXT_VARIABLE)
> > +             return EFI_DEVICE_ERROR;
> >
> > -     if (rsp_data->length < sizeof(*rsp_data)) {
> > -             efi_status = EFI_DEVICE_ERROR;
> > -             goto out_free;
> > -     }
> > +     if (rsp_data->length < sizeof(*rsp_data))
> > +             return EFI_DEVICE_ERROR;
> >
> >       if (rsp_data->status) {
> >               dev_dbg(qcuefi_dev(qcuefi), "%s: uefisecapp error: 0x%x\n",
> > @@ -595,77 +551,59 @@ static efi_status_t qsee_uefi_get_next_variable(struct qcuefi_client *qcuefi,
> >               if (efi_status == EFI_BUFFER_TOO_SMALL)
> >                       *name_size = rsp_data->name_size;
> >
> > -             goto out_free;
> > +             return efi_status;
> >       }
> >
> > -     if (rsp_data->length > rsp_size) {
> > -             efi_status = EFI_DEVICE_ERROR;
> > -             goto out_free;
> > -     }
> > +     if (rsp_data->length > rsp_size)
> > +             return EFI_DEVICE_ERROR;
> >
> > -     if (rsp_data->name_offset + rsp_data->name_size > rsp_data->length) {
> > -             efi_status = EFI_DEVICE_ERROR;
> > -             goto out_free;
> > -     }
> > +     if (rsp_data->name_offset + rsp_data->name_size > rsp_data->length)
> > +             return EFI_DEVICE_ERROR;
> >
> > -     if (rsp_data->guid_offset + rsp_data->guid_size > rsp_data->length) {
> > -             efi_status = EFI_DEVICE_ERROR;
> > -             goto out_free;
> > -     }
> > +     if (rsp_data->guid_offset + rsp_data->guid_size > rsp_data->length)
> > +             return EFI_DEVICE_ERROR;
> >
> >       if (rsp_data->name_size > *name_size) {
> >               *name_size = rsp_data->name_size;
> > -             efi_status = EFI_BUFFER_TOO_SMALL;
> > -             goto out_free;
> > +             return EFI_BUFFER_TOO_SMALL;
> >       }
> >
> > -     if (rsp_data->guid_size != sizeof(*guid)) {
> > -             efi_status = EFI_DEVICE_ERROR;
> > -             goto out_free;
> > -     }
> > +     if (rsp_data->guid_size != sizeof(*guid))
> > +             return EFI_DEVICE_ERROR;
> >
> >       memcpy(guid, ((void *)rsp_data) + rsp_data->guid_offset, rsp_data->guid_size);
> >       status = ucs2_strscpy(name, ((void *)rsp_data) + rsp_data->name_offset,
> >                             rsp_data->name_size / sizeof(*name));
> >       *name_size = rsp_data->name_size;
> >
> > -     if (status < 0) {
> > +     if (status < 0)
> >               /*
> >                * Return EFI_DEVICE_ERROR here because the buffer size should
> >                * have already been validated above, causing this function to
> >                * bail with EFI_BUFFER_TOO_SMALL.
> >                */
> >               return EFI_DEVICE_ERROR;
> > -     }
>
> Personally (no idea what the actual style guide says) leaving braces
> around the multiline if statement would be nice.... that being said,
> that's my opinion :)
>
> <snip>
> > @@ -704,12 +635,7 @@ static efi_status_t qsee_uefi_query_variable_info(struct qcuefi_client *qcuefi,
> >       if (max_variable_size)
> >               *max_variable_size = rsp_data->max_variable_size;
> >
> > -out_free:
> > -     kfree(rsp_data);
> > -out_free_req:
> > -     kfree(req_data);
> > -out:
> > -     return efi_status;
> > +     return EFI_SUCCESS;
> >  }
> >
> >  /* -- Global efivar interface. ---------------------------------------------- */
> > @@ -838,6 +764,10 @@ static int qcom_uefisecapp_probe(struct auxiliary_device *aux_dev,
> >       if (status)
> >               qcuefi_set_reference(NULL);
> >
> > +     qcuefi->mempool = devm_qcom_tzmem_pool_new(&aux_dev->dev, SZ_256K);
>
> Any particular reason for this size? Just curious, it was (one) of the
> reasons I had not marked patch 4 yet (it looks good, but I wanted to get
> through the series to digest the Kconfig as well).
>

I cannot test this. Do you know what the minimum correct size would be?

Bart

> Reviewed-by: Andrew Halaney <ahalaney@xxxxxxxxxx>
>