Hi Harsimran, Thanks for fixingthe callbacks. The logic is correct now but please split these into 4 different patches on the next revision, one for each runtime call that changes.
Thanks /Ilias On Sat, 27 Jun 2026 at 17:44, Harsimran Singh Tungal <[email protected]> wrote: > > Route EFI runtime variable APIs through FF-A MM communication > > Route EFI runtime variable services through the FF-A/MM backend in > lib/efi_loader/efi_variable_tee.c. After ExitBootServices(), > GetVariable(), SetVariable(), GetNextVariableName(), and > QueryVariableInfo() use the runtime entry points and continue to reach > the MM secure partition. > > Keep the existing boot-time helpers unchanged and add runtime service > wrappers for variable access and property handling. Reuse the > runtime-safe setup_mm_hdr() and common mm_communicate() path, which > selects the FF-A transport appropriate for the current phase, and use > the EFI runtime-safe memory helpers in the runtime-only code. > > Reviewed-by: Simon Glass <[email protected]> > Signed-off-by: Harsimran Singh Tungal <[email protected]> > --- > lib/efi_loader/efi_variable_tee.c | 344 ++++++++++++++++++++++++++++-- > 1 file changed, 326 insertions(+), 18 deletions(-) > > diff --git a/lib/efi_loader/efi_variable_tee.c > b/lib/efi_loader/efi_variable_tee.c > index fe205bdf966..474dd186a3e 100644 > --- a/lib/efi_loader/efi_variable_tee.c > +++ b/lib/efi_loader/efi_variable_tee.c > @@ -716,6 +716,38 @@ out: > return ret; > } > > +static efi_status_t __efi_runtime set_property_int_runtime(const u16 > *variable_name, > + efi_uintn_t > name_size, > + const efi_guid_t > *vendor, > + struct > var_check_property *var_property) > +{ > + struct smm_variable_var_check_property *smm_property; > + efi_uintn_t payload_size; > + u8 *comm_buf = NULL; > + efi_status_t ret; > + > + payload_size = sizeof(*smm_property) + name_size; > + if (payload_size > max_payload_size) { > + ret = EFI_INVALID_PARAMETER; > + return ret; > + } > + comm_buf = setup_mm_hdr((void **)&smm_property, payload_size, > + > SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_SET, > + &ret); > + if (!comm_buf) > + return ret; > + > + efi_memcpy_runtime(&smm_property->guid, vendor, sizeof(*vendor)); > + smm_property->name_size = name_size; > + efi_memcpy_runtime(&smm_property->property, var_property, > + sizeof(smm_property->property)); > + efi_memcpy_runtime(smm_property->name, variable_name, name_size); > + > + ret = mm_communicate(comm_buf, payload_size); > + > + return ret; > +} > + > static efi_status_t get_property_int(const u16 *variable_name, > efi_uintn_t name_size, > const efi_guid_t *vendor, > @@ -761,6 +793,49 @@ out: > return ret; > } > > +static efi_status_t __efi_runtime get_property_int_runtime(const u16 > *variable_name, > + efi_uintn_t > name_size, > + const efi_guid_t > *vendor, > + struct > var_check_property *var_property) > +{ > + struct smm_variable_var_check_property *smm_property; > + efi_uintn_t payload_size; > + u8 *comm_buf = NULL; > + efi_status_t ret; > + > + efi_memset_runtime(var_property, 0, sizeof(*var_property)); > + payload_size = sizeof(*smm_property) + name_size; > + if (payload_size > max_payload_size) { > + ret = EFI_INVALID_PARAMETER; > + return ret; > + } > + comm_buf = setup_mm_hdr((void **)&smm_property, payload_size, > + > SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_GET, > + &ret); > + if (!comm_buf) > + return ret; > + > + efi_memcpy_runtime(&smm_property->guid, vendor, > sizeof(smm_property->guid)); > + smm_property->name_size = name_size; > + efi_memcpy_runtime(smm_property->name, variable_name, name_size); > + > + ret = mm_communicate(comm_buf, payload_size); > + /* > + * Currently only R/O property is supported in StMM. > + * Variables that are not set to R/O will not set the property in StMM > + * and the call will return EFI_NOT_FOUND. We are setting the > + * properties to 0x0 so checking against that is enough for the > + * EFI_NOT_FOUND case. > + */ > + if (ret == EFI_NOT_FOUND) > + return EFI_SUCCESS; > + if (ret != EFI_SUCCESS) > + return ret; > + efi_memcpy_runtime(var_property, &smm_property->property, > sizeof(*var_property)); > + > + return EFI_SUCCESS; > +} > + > efi_status_t efi_get_variable_int(const u16 *variable_name, > const efi_guid_t *vendor, > u32 *attributes, efi_uintn_t *data_size, > @@ -848,6 +923,93 @@ out: > return ret; > } > > +efi_status_t __efi_runtime EFIAPI > +efi_get_variable_int_runtime(u16 *variable_name, const efi_guid_t *vendor, > + u32 *attributes, efi_uintn_t *data_size, void > *data) > +{ > + struct var_check_property var_property; > + struct smm_variable_access *var_acc; > + efi_uintn_t payload_size; > + efi_uintn_t name_size; > + efi_uintn_t tmp_dsize; > + u8 *comm_buf = NULL; > + efi_status_t ret, tmp; > + u32 var_attr = 0; > + > + if (!variable_name || !vendor || !data_size) { > + ret = EFI_INVALID_PARAMETER; > + return ret; > + } > + > + /* Check payload size */ > + name_size = u16_strsize(variable_name); > + if (name_size > max_payload_size - MM_VARIABLE_ACCESS_HEADER_SIZE) { > + ret = EFI_INVALID_PARAMETER; > + return ret; > + } > + > + /* Trim output buffer size */ > + tmp_dsize = *data_size; > + if (name_size + tmp_dsize > > + max_payload_size - MM_VARIABLE_ACCESS_HEADER_SIZE) { > + tmp_dsize = max_payload_size - > + MM_VARIABLE_ACCESS_HEADER_SIZE - > + name_size; > + } > + > + /* Get communication buffer and initialize header */ > + payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + tmp_dsize; > + comm_buf = setup_mm_hdr((void **)&var_acc, payload_size, > + SMM_VARIABLE_FUNCTION_GET_VARIABLE, &ret); > + if (!comm_buf) > + return ret; > + > + /* Fill in contents */ > + efi_memcpy_runtime(&var_acc->guid, vendor, sizeof(var_acc->guid)); > + var_acc->data_size = tmp_dsize; > + var_acc->name_size = name_size; > + var_acc->attr = attributes ? *attributes : 0; > + efi_memcpy_runtime(var_acc->name, variable_name, name_size); > + > + /* Communicate */ > + ret = mm_communicate(comm_buf, payload_size); > + if (ret != EFI_SUCCESS && ret != EFI_BUFFER_TOO_SMALL) > + return ret; > + > + /* Update with reported data size for trimmed case */ > + *data_size = var_acc->data_size; > + if (attributes) > + var_attr = var_acc->attr; > + > + /* Copy the data if ret is EFI_SUCCESS */ > + if (ret == EFI_SUCCESS) { > + if (data) > + efi_memcpy_runtime(data, (u8 *)var_acc->name + > var_acc->name_size, > + var_acc->data_size); > + else > + ret = EFI_INVALID_PARAMETER; > + } > + > + /* > + * UEFI > 2.7 needs the attributes set even if the buffer is > + * smaller > + */ > + if (attributes) { > + tmp = get_property_int_runtime(variable_name, name_size, > vendor, > + &var_property); > + if (tmp != EFI_SUCCESS) { > + ret = tmp; > + return ret; > + } > + *attributes = var_attr; > + if (var_property.property & > + VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY) > + *attributes |= EFI_VARIABLE_READ_ONLY; > + } > + > + return ret; > +} > + > efi_status_t efi_get_next_variable_name_int(efi_uintn_t *variable_name_size, > u16 *variable_name, > efi_guid_t *guid) > @@ -912,6 +1074,68 @@ out: > return ret; > } > > +efi_status_t __efi_runtime EFIAPI > +efi_get_next_variable_name_int_runtime(efi_uintn_t *variable_name_size, > + u16 *variable_name, efi_guid_t *guid) > +{ > + struct smm_variable_getnext *var_getnext; > + efi_uintn_t payload_size; > + efi_uintn_t out_name_size; > + efi_uintn_t in_name_size; > + u8 *comm_buf = NULL; > + efi_status_t ret; > + > + if (!variable_name_size || !variable_name || !guid) { > + ret = EFI_INVALID_PARAMETER; > + return ret; > + } > + > + out_name_size = *variable_name_size; > + in_name_size = u16_strsize(variable_name); > + > + if (out_name_size < in_name_size) { > + ret = EFI_INVALID_PARAMETER; > + return ret; > + } > + > + if (in_name_size > max_payload_size - > MM_VARIABLE_GET_NEXT_HEADER_SIZE) { > + ret = EFI_INVALID_PARAMETER; > + return ret; > + } > + > + /* Trim output buffer size */ > + if (out_name_size > max_payload_size - > MM_VARIABLE_GET_NEXT_HEADER_SIZE) > + out_name_size = max_payload_size - > MM_VARIABLE_GET_NEXT_HEADER_SIZE; > + > + payload_size = MM_VARIABLE_GET_NEXT_HEADER_SIZE + out_name_size; > + comm_buf = setup_mm_hdr((void **)&var_getnext, payload_size, > + SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME, > + &ret); > + if (!comm_buf) > + return ret; > + > + /* Fill in contents */ > + efi_memcpy_runtime(&var_getnext->guid, guid, sizeof(*guid)); > + var_getnext->name_size = out_name_size; > + efi_memcpy_runtime(var_getnext->name, variable_name, in_name_size); > + efi_memset_runtime((u8 *)var_getnext->name + in_name_size, 0x0, > + out_name_size - in_name_size); > + > + /* Communicate */ > + ret = mm_communicate(comm_buf, payload_size); > + if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) { > + /* Update with reported data size for trimmed case */ > + *variable_name_size = var_getnext->name_size; > + } > + if (ret != EFI_SUCCESS) > + return ret; > + > + efi_memcpy_runtime(guid, &var_getnext->guid, sizeof(*guid)); > + efi_memcpy_runtime(variable_name, var_getnext->name, > var_getnext->name_size); > + > + return ret; > +} > + > efi_status_t efi_set_variable_int(const u16 *variable_name, > const efi_guid_t *vendor, u32 attributes, > efi_uintn_t data_size, const void *data, > @@ -994,7 +1218,7 @@ efi_status_t efi_set_variable_int(const u16 > *variable_name, > var_property.property |= > VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY; > var_property.attributes = attributes; > var_property.minsize = 1; > - var_property.maxsize = var_acc->data_size; > + var_property.maxsize = data_size; > ret = set_property_int(variable_name, name_size, vendor, > &var_property); > } > > @@ -1045,7 +1269,7 @@ out: > } > > /** > - * efi_query_variable_info() - get information about EFI variables > + * efi_query_variable_info_int_runtime() - get information about EFI > variables > * > * This function implements the QueryVariableInfo() runtime service. > * > @@ -1054,24 +1278,50 @@ out: > * > * @attributes: bitmask to select variables > to be > * queried > - * @maximum_variable_storage_size: maximum size of storage area for the > + * @max_variable_storage_size: maximum size of storage area for the > * selected variable types > - * @remaining_variable_storage_size: remaining size of storage are for the > + * @remain_variable_storage_size: remaining size of storage are for the > * selected variable types > - * @maximum_variable_size: maximum size of a variable of the > + * @max_variable_size: maximum size of a variable of the > * selected type > * Return: status code > */ > efi_status_t EFIAPI __efi_runtime > -efi_query_variable_info_runtime(u32 attributes, u64 > *max_variable_storage_size, > - u64 *remain_variable_storage_size, > - u64 *max_variable_size) > +efi_query_variable_info_int_runtime(u32 attributes, u64 > *max_variable_storage_size, > + u64 *remain_variable_storage_size, > + u64 *max_variable_size) > { > - return EFI_UNSUPPORTED; > + struct smm_variable_query_info *mm_query_info; > + efi_uintn_t payload_size; > + efi_status_t ret; > + u8 *comm_buf; > + > + if (!max_variable_storage_size || > + !remain_variable_storage_size || > + !max_variable_size || !attributes) > + return EFI_INVALID_PARAMETER; > + > + payload_size = sizeof(*mm_query_info); > + comm_buf = setup_mm_hdr((void **)&mm_query_info, payload_size, > + SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO, > + &ret); > + if (!comm_buf) > + return ret; > + > + mm_query_info->attr = attributes; > + ret = mm_communicate(comm_buf, payload_size); > + if (ret != EFI_SUCCESS) > + return ret; > + *max_variable_storage_size = mm_query_info->max_variable_storage; > + *remain_variable_storage_size = > + mm_query_info->remaining_variable_storage; > + *max_variable_size = mm_query_info->max_variable_size; > + > + return ret; > } > > /** > - * efi_set_variable_runtime() - runtime implementation of SetVariable() > + * efi_set_variable_int_runtime() - runtime implementation of SetVariable() > * > * @variable_name: name of the variable > * @guid: vendor GUID > @@ -1081,11 +1331,69 @@ efi_query_variable_info_runtime(u32 attributes, u64 > *max_variable_storage_size, > * Return: status code > */ > static efi_status_t __efi_runtime EFIAPI > -efi_set_variable_runtime(u16 *variable_name, const efi_guid_t *guid, > - u32 attributes, efi_uintn_t data_size, > - const void *data) > +efi_set_variable_int_runtime(u16 *variable_name, const efi_guid_t *guid, > + u32 attributes, efi_uintn_t data_size, > + const void *data) > { > - return EFI_UNSUPPORTED; > + efi_status_t ret, mm_communicate_ret = EFI_SUCCESS; > + struct var_check_property var_property; > + struct smm_variable_access *var_acc; > + efi_uintn_t payload_size; > + efi_uintn_t name_size; > + u8 *comm_buf = NULL; > + bool ro; > + > + if (!variable_name || variable_name[0] == 0 || !guid) > + return EFI_INVALID_PARAMETER; > + > + if (data_size > 0 && !data) > + return EFI_INVALID_PARAMETER; > + > + /* Check payload size */ > + name_size = u16_strsize(variable_name); > + payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + data_size; > + if (payload_size > max_payload_size) > + return EFI_INVALID_PARAMETER; > + > + ro = !!(attributes & EFI_VARIABLE_READ_ONLY); > + attributes &= EFI_VARIABLE_MASK; > + > + ret = get_property_int_runtime(variable_name, name_size, guid, > + &var_property); > + if (ret != EFI_SUCCESS) > + return ret; > + > + if (var_property.property & VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY) > + return EFI_WRITE_PROTECTED; > + > + comm_buf = setup_mm_hdr((void **)&var_acc, payload_size, > + SMM_VARIABLE_FUNCTION_SET_VARIABLE, &ret); > + if (!comm_buf) > + return ret; > + > + /* Fill in contents */ > + efi_memcpy_runtime(&var_acc->guid, guid, sizeof(*guid)); > + var_acc->data_size = data_size; > + var_acc->name_size = name_size; > + var_acc->attr = attributes; > + efi_memcpy_runtime(var_acc->name, variable_name, name_size); > + efi_memcpy_runtime((u8 *)var_acc->name + name_size, data, data_size); > + > + /* Communicate */ > + ret = mm_communicate(comm_buf, payload_size); > + if (ret != EFI_SUCCESS) > + mm_communicate_ret = ret; > + > + if (ro && !(var_property.property & > VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY)) { > + var_property.revision = VAR_CHECK_VARIABLE_PROPERTY_REVISION; > + var_property.property |= > VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY; > + var_property.attributes = attributes; > + var_property.minsize = 1; > + var_property.maxsize = data_size; > + ret = set_property_int_runtime(variable_name, name_size, > guid, &var_property); > + } > + > + return (mm_communicate_ret == EFI_SUCCESS) ? ret : mm_communicate_ret; > } > > /** > @@ -1118,11 +1426,11 @@ void efi_variables_boot_exit_notify(void) > > /* Update runtime service table */ > efi_runtime_services.query_variable_info = > - efi_query_variable_info_runtime; > - efi_runtime_services.get_variable = efi_get_variable_runtime; > + efi_query_variable_info_int_runtime; > + efi_runtime_services.get_variable = efi_get_variable_int_runtime; > efi_runtime_services.get_next_variable_name = > - efi_get_next_variable_name_runtime; > - efi_runtime_services.set_variable = efi_set_variable_runtime; > + efi_get_next_variable_name_int_runtime; > + efi_runtime_services.set_variable = efi_set_variable_int_runtime; > efi_update_table_header_crc32(&efi_runtime_services.hdr); > > /* Record that ExitBootServices() has been called */ > -- > 2.34.1 >
