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

From: Andrew Halaney
Date: Tue Oct 10 2023 - 19:03:56 EST


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).

Reviewed-by: Andrew Halaney <ahalaney@xxxxxxxxxx>