From 6bb3703aa52c9b5bb9716cbeae7350247b675209 Mon Sep 17 00:00:00 2001 From: Masahisa Kojima Date: Tue, 7 Nov 2023 14:40:52 +0900 Subject: efi: expose efivar generic ops register function This is a preparation for supporting efivar operations provided by other than efi subsystem. Both register and unregister functions are exposed so that non-efi subsystem can revert the efi generic operation. Acked-by: Sumit Garg Co-developed-by: Ilias Apalodimas Signed-off-by: Ilias Apalodimas Signed-off-by: Masahisa Kojima Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'drivers/firmware/efi') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 9d3910d1abe1..32a67c61c3b8 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -231,6 +231,18 @@ static void generic_ops_unregister(void) efivars_unregister(&generic_efivars); } +void efivars_generic_ops_register(void) +{ + generic_ops_register(); +} +EXPORT_SYMBOL_GPL(efivars_generic_ops_register); + +void efivars_generic_ops_unregister(void) +{ + generic_ops_unregister(); +} +EXPORT_SYMBOL_GPL(efivars_generic_ops_unregister); + #ifdef CONFIG_EFI_CUSTOM_SSDT_OVERLAYS #define EFIVAR_SSDT_NAME_MAX 16UL static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata; -- cgit v1.2.3 From c44b6be62e8dd4ee0a308c36a70620613e6fc55f Mon Sep 17 00:00:00 2001 From: Masahisa Kojima Date: Tue, 7 Nov 2023 14:40:54 +0900 Subject: efi: Add tee-based EFI variable driver When the flash is not owned by the non-secure world, accessing the EFI variables is straight-forward and done via EFI Runtime Variable Services. In this case, critical variables for system integrity and security are normally stored in the dedicated secure storage and can only be manipulated directly from the secure world. Usually, small embedded devices don't have the special dedicated secure storage. The eMMC device with an RPMB partition is becoming more common, and we can use this RPMB partition to store the EFI Variables. The eMMC device is typically owned by the non-secure world (Linux in our case). There is an existing solution utilizing eMMC RPMB partition for EFI Variables, it is implemented by interacting with TEE (OP-TEE in this case), StandaloneMM (as EFI Variable Service Pseudo TA), eMMC driver and tee-supplicant. The last piece is the tee-based variable access driver to interact with TEE and StandaloneMM. So let's add the kernel functions needed. This feature is implemented as a kernel module. StMM PTA has TA_FLAG_DEVICE_ENUM_SUPP flag when registered to OP-TEE so that this tee_stmm_efi module is probed after tee-supplicant starts, since "SetVariable" EFI Runtime Variable Service requires to interact with tee-supplicant. Acked-by: Sumit Garg Co-developed-by: Ilias Apalodimas Signed-off-by: Ilias Apalodimas Signed-off-by: Masahisa Kojima Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/Kconfig | 15 + drivers/firmware/efi/Makefile | 1 + drivers/firmware/efi/stmm/mm_communication.h | 236 ++++++++++ drivers/firmware/efi/stmm/tee_stmm_efi.c | 616 +++++++++++++++++++++++++++ 4 files changed, 868 insertions(+) create mode 100644 drivers/firmware/efi/stmm/mm_communication.h create mode 100644 drivers/firmware/efi/stmm/tee_stmm_efi.c (limited to 'drivers/firmware/efi') diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig index cb374b2da9b7..72f2537d90ca 100644 --- a/drivers/firmware/efi/Kconfig +++ b/drivers/firmware/efi/Kconfig @@ -301,3 +301,18 @@ config UEFI_CPER_X86 bool depends on UEFI_CPER && X86 default y + +config TEE_STMM_EFI + tristate "TEE-based EFI runtime variable service driver" + depends on EFI && OPTEE + help + Select this config option if TEE is compiled to include StandAloneMM + as a separate secure partition. It has the ability to check and store + EFI variables on an RPMB or any other non-volatile medium used by + StandAloneMM. + + Enabling this will change the EFI runtime services from the firmware + provided functions to TEE calls. + + To compile this driver as a module, choose M here: the module + will be called tee_stmm_efi. diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index e489fefd23da..a2d0009560d0 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -42,3 +42,4 @@ obj-$(CONFIG_EFI_EARLYCON) += earlycon.o obj-$(CONFIG_UEFI_CPER_ARM) += cper-arm.o obj-$(CONFIG_UEFI_CPER_X86) += cper-x86.o obj-$(CONFIG_UNACCEPTED_MEMORY) += unaccepted_memory.o +obj-$(CONFIG_TEE_STMM_EFI) += stmm/tee_stmm_efi.o diff --git a/drivers/firmware/efi/stmm/mm_communication.h b/drivers/firmware/efi/stmm/mm_communication.h new file mode 100644 index 000000000000..52a1f32cd1eb --- /dev/null +++ b/drivers/firmware/efi/stmm/mm_communication.h @@ -0,0 +1,236 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Headers for EFI variable service via StandAloneMM, EDK2 application running + * in OP-TEE. Most of the structs and defines resemble the EDK2 naming. + * + * Copyright (c) 2017, Intel Corporation. All rights reserved. + * Copyright (C) 2020 Linaro Ltd. + */ + +#ifndef _MM_COMMUNICATION_H_ +#define _MM_COMMUNICATION_H_ + +/* + * Interface to the pseudo Trusted Application (TA), which provides a + * communication channel with the Standalone MM (Management Mode) + * Secure Partition running at Secure-EL0 + */ + +#define PTA_STMM_CMD_COMMUNICATE 0 + +/* + * Defined in OP-TEE, this UUID is used to identify the pseudo-TA. + * OP-TEE is using big endian GUIDs while UEFI uses little endian ones + */ +#define PTA_STMM_UUID \ + UUID_INIT(0xed32d533, 0x99e6, 0x4209, \ + 0x9c, 0xc0, 0x2d, 0x72, 0xcd, 0xd9, 0x98, 0xa7) + +#define EFI_MM_VARIABLE_GUID \ + EFI_GUID(0xed32d533, 0x99e6, 0x4209, \ + 0x9c, 0xc0, 0x2d, 0x72, 0xcd, 0xd9, 0x98, 0xa7) + +/** + * struct efi_mm_communicate_header - Header used for SMM variable communication + + * @header_guid: header use for disambiguation of content + * @message_len: length of the message. Does not include the size of the + * header + * @data: payload of the message + * + * Defined in the PI spec as EFI_MM_COMMUNICATE_HEADER. + * To avoid confusion in interpreting frames, the communication buffer should + * always begin with efi_mm_communicate_header. + */ +struct efi_mm_communicate_header { + efi_guid_t header_guid; + size_t message_len; + u8 data[]; +} __packed; + +#define MM_COMMUNICATE_HEADER_SIZE \ + (sizeof(struct efi_mm_communicate_header)) + +/* SPM return error codes */ +#define ARM_SVC_SPM_RET_SUCCESS 0 +#define ARM_SVC_SPM_RET_NOT_SUPPORTED -1 +#define ARM_SVC_SPM_RET_INVALID_PARAMS -2 +#define ARM_SVC_SPM_RET_DENIED -3 +#define ARM_SVC_SPM_RET_NO_MEMORY -5 + +#define SMM_VARIABLE_FUNCTION_GET_VARIABLE 1 +/* + * The payload for this function is + * SMM_VARIABLE_COMMUNICATE_GET_NEXT_VARIABLE_NAME. + */ +#define SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME 2 +/* + * The payload for this function is SMM_VARIABLE_COMMUNICATE_ACCESS_VARIABLE. + */ +#define SMM_VARIABLE_FUNCTION_SET_VARIABLE 3 +/* + * The payload for this function is + * SMM_VARIABLE_COMMUNICATE_QUERY_VARIABLE_INFO. + */ +#define SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO 4 +/* + * It is a notify event, no extra payload for this function. + */ +#define SMM_VARIABLE_FUNCTION_READY_TO_BOOT 5 +/* + * It is a notify event, no extra payload for this function. + */ +#define SMM_VARIABLE_FUNCTION_EXIT_BOOT_SERVICE 6 +/* + * The payload for this function is VARIABLE_INFO_ENTRY. + * The GUID in EFI_SMM_COMMUNICATE_HEADER is gEfiSmmVariableProtocolGuid. + */ +#define SMM_VARIABLE_FUNCTION_GET_STATISTICS 7 +/* + * The payload for this function is SMM_VARIABLE_COMMUNICATE_LOCK_VARIABLE + */ +#define SMM_VARIABLE_FUNCTION_LOCK_VARIABLE 8 + +#define SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_SET 9 + +#define SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_GET 10 + +#define SMM_VARIABLE_FUNCTION_GET_PAYLOAD_SIZE 11 +/* + * The payload for this function is + * SMM_VARIABLE_COMMUNICATE_RUNTIME_VARIABLE_CACHE_CONTEXT + */ +#define SMM_VARIABLE_FUNCTION_INIT_RUNTIME_VARIABLE_CACHE_CONTEXT 12 + +#define SMM_VARIABLE_FUNCTION_SYNC_RUNTIME_CACHE 13 +/* + * The payload for this function is + * SMM_VARIABLE_COMMUNICATE_GET_RUNTIME_CACHE_INFO + */ +#define SMM_VARIABLE_FUNCTION_GET_RUNTIME_CACHE_INFO 14 + +/** + * struct smm_variable_communicate_header - Used for SMM variable communication + + * @function: function to call in Smm. + * @ret_status: return status + * @data: payload + */ +struct smm_variable_communicate_header { + size_t function; + efi_status_t ret_status; + u8 data[]; +}; + +#define MM_VARIABLE_COMMUNICATE_SIZE \ + (sizeof(struct smm_variable_communicate_header)) + +/** + * struct smm_variable_access - Used to communicate with StMM by + * SetVariable and GetVariable. + + * @guid: vendor GUID + * @data_size: size of EFI variable data + * @name_size: size of EFI name + * @attr: attributes + * @name: variable name + * + */ +struct smm_variable_access { + efi_guid_t guid; + size_t data_size; + size_t name_size; + u32 attr; + u16 name[]; +}; + +#define MM_VARIABLE_ACCESS_HEADER_SIZE \ + (sizeof(struct smm_variable_access)) +/** + * struct smm_variable_payload_size - Used to get the max allowed + * payload used in StMM. + * + * @size: size to fill in + * + */ +struct smm_variable_payload_size { + size_t size; +}; + +/** + * struct smm_variable_getnext - Used to communicate with StMM for + * GetNextVariableName. + * + * @guid: vendor GUID + * @name_size: size of the name of the variable + * @name: variable name + * + */ +struct smm_variable_getnext { + efi_guid_t guid; + size_t name_size; + u16 name[]; +}; + +#define MM_VARIABLE_GET_NEXT_HEADER_SIZE \ + (sizeof(struct smm_variable_getnext)) + +/** + * struct smm_variable_query_info - Used to communicate with StMM for + * QueryVariableInfo. + * + * @max_variable_storage: max available storage + * @remaining_variable_storage: remaining available storage + * @max_variable_size: max variable supported size + * @attr: attributes to query storage for + * + */ +struct smm_variable_query_info { + u64 max_variable_storage; + u64 remaining_variable_storage; + u64 max_variable_size; + u32 attr; +}; + +#define VAR_CHECK_VARIABLE_PROPERTY_REVISION 0x0001 +#define VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY BIT(0) +/** + * struct var_check_property - Used to store variable properties in StMM + * + * @revision: magic revision number for variable property checking + * @property: properties mask for the variable used in StMM. + * Currently RO flag is supported + * @attributes: variable attributes used in StMM checking when properties + * for a variable are enabled + * @minsize: minimum allowed size for variable payload checked against + * smm_variable_access->datasize in StMM + * @maxsize: maximum allowed size for variable payload checked against + * smm_variable_access->datasize in StMM + * + */ +struct var_check_property { + u16 revision; + u16 property; + u32 attributes; + size_t minsize; + size_t maxsize; +}; + +/** + * struct smm_variable_var_check_property - Used to communicate variable + * properties with StMM + * + * @guid: vendor GUID + * @name_size: size of EFI name + * @property: variable properties struct + * @name: variable name + * + */ +struct smm_variable_var_check_property { + efi_guid_t guid; + size_t name_size; + struct var_check_property property; + u16 name[]; +}; + +#endif /* _MM_COMMUNICATION_H_ */ diff --git a/drivers/firmware/efi/stmm/tee_stmm_efi.c b/drivers/firmware/efi/stmm/tee_stmm_efi.c new file mode 100644 index 000000000000..f741ca279052 --- /dev/null +++ b/drivers/firmware/efi/stmm/tee_stmm_efi.c @@ -0,0 +1,616 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * EFI variable service via TEE + * + * Copyright (C) 2022 Linaro + */ + +#include +#include +#include +#include +#include +#include +#include "mm_communication.h" + +static struct efivars tee_efivars; +static struct efivar_operations tee_efivar_ops; + +static size_t max_buffer_size; /* comm + var + func + data */ +static size_t max_payload_size; /* func + data */ + +struct tee_stmm_efi_private { + struct tee_context *ctx; + u32 session; + struct device *dev; +}; + +static struct tee_stmm_efi_private pvt_data; + +/* UUID of the stmm PTA */ +static const struct tee_client_device_id tee_stmm_efi_id_table[] = { + {PTA_STMM_UUID}, + {} +}; + +static int tee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) +{ + /* currently only OP-TEE is supported as a communication path */ + if (ver->impl_id == TEE_IMPL_ID_OPTEE) + return 1; + else + return 0; +} + +/** + * tee_mm_communicate() - Pass a buffer to StandaloneMM running in TEE + * + * @comm_buf: locally allocated communication buffer + * @dsize: buffer size + * Return: status code + */ +static efi_status_t tee_mm_communicate(void *comm_buf, size_t dsize) +{ + size_t buf_size; + struct efi_mm_communicate_header *mm_hdr; + struct tee_ioctl_invoke_arg arg; + struct tee_param param[4]; + struct tee_shm *shm = NULL; + int rc; + + if (!comm_buf) + return EFI_INVALID_PARAMETER; + + mm_hdr = (struct efi_mm_communicate_header *)comm_buf; + buf_size = mm_hdr->message_len + sizeof(efi_guid_t) + sizeof(size_t); + + if (dsize != buf_size) + return EFI_INVALID_PARAMETER; + + shm = tee_shm_register_kernel_buf(pvt_data.ctx, comm_buf, buf_size); + if (IS_ERR(shm)) { + dev_err(pvt_data.dev, "Unable to register shared memory\n"); + return EFI_UNSUPPORTED; + } + + memset(&arg, 0, sizeof(arg)); + arg.func = PTA_STMM_CMD_COMMUNICATE; + arg.session = pvt_data.session; + arg.num_params = 4; + + memset(param, 0, sizeof(param)); + param[0].attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT; + param[0].u.memref.size = buf_size; + param[0].u.memref.shm = shm; + param[1].attr = TEE_IOCTL_PARAM_ATTR_TYPE_VALUE_OUTPUT; + param[2].attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE; + param[3].attr = TEE_IOCTL_PARAM_ATTR_TYPE_NONE; + + rc = tee_client_invoke_func(pvt_data.ctx, &arg, param); + tee_shm_free(shm); + + if (rc < 0 || arg.ret != 0) { + dev_err(pvt_data.dev, + "PTA_STMM_CMD_COMMUNICATE invoke error: 0x%x\n", arg.ret); + return EFI_DEVICE_ERROR; + } + + switch (param[1].u.value.a) { + case ARM_SVC_SPM_RET_SUCCESS: + return EFI_SUCCESS; + + case ARM_SVC_SPM_RET_INVALID_PARAMS: + return EFI_INVALID_PARAMETER; + + case ARM_SVC_SPM_RET_DENIED: + return EFI_ACCESS_DENIED; + + case ARM_SVC_SPM_RET_NO_MEMORY: + return EFI_OUT_OF_RESOURCES; + + default: + return EFI_ACCESS_DENIED; + } +} + +/** + * mm_communicate() - Adjust the communication buffer to StandAlonneMM and send + * it to TEE + * + * @comm_buf: locally allocated communication buffer, buffer should + * be enough big to have some headers and payload + * @payload_size: payload size + * Return: status code + */ +static efi_status_t mm_communicate(u8 *comm_buf, size_t payload_size) +{ + size_t dsize; + efi_status_t ret; + struct efi_mm_communicate_header *mm_hdr; + struct smm_variable_communicate_header *var_hdr; + + dsize = payload_size + MM_COMMUNICATE_HEADER_SIZE + + MM_VARIABLE_COMMUNICATE_SIZE; + mm_hdr = (struct efi_mm_communicate_header *)comm_buf; + var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data; + + ret = tee_mm_communicate(comm_buf, dsize); + if (ret != EFI_SUCCESS) { + dev_err(pvt_data.dev, "%s failed!\n", __func__); + return ret; + } + + return var_hdr->ret_status; +} + +/** + * setup_mm_hdr() - Allocate a buffer for StandAloneMM and initialize the + * header data. + * + * @dptr: pointer address to store allocated buffer + * @payload_size: payload size + * @func: standAloneMM function number + * @ret: EFI return code + * Return: pointer to corresponding StandAloneMM function buffer or NULL + */ +static void *setup_mm_hdr(u8 **dptr, size_t payload_size, size_t func, + efi_status_t *ret) +{ + const efi_guid_t mm_var_guid = EFI_MM_VARIABLE_GUID; + struct efi_mm_communicate_header *mm_hdr; + struct smm_variable_communicate_header *var_hdr; + u8 *comm_buf; + + /* In the init function we initialize max_buffer_size with + * get_max_payload(). So skip the test if max_buffer_size is initialized + * StandAloneMM will perform similar checks and drop the buffer if it's + * too long + */ + if (max_buffer_size && + max_buffer_size < (MM_COMMUNICATE_HEADER_SIZE + + MM_VARIABLE_COMMUNICATE_SIZE + payload_size)) { + *ret = EFI_INVALID_PARAMETER; + return NULL; + } + + comm_buf = kzalloc(MM_COMMUNICATE_HEADER_SIZE + + MM_VARIABLE_COMMUNICATE_SIZE + payload_size, + GFP_KERNEL); + if (!comm_buf) { + *ret = EFI_OUT_OF_RESOURCES; + return NULL; + } + + mm_hdr = (struct efi_mm_communicate_header *)comm_buf; + memcpy(&mm_hdr->header_guid, &mm_var_guid, sizeof(mm_hdr->header_guid)); + mm_hdr->message_len = MM_VARIABLE_COMMUNICATE_SIZE + payload_size; + + var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data; + var_hdr->function = func; + if (dptr) + *dptr = comm_buf; + *ret = EFI_SUCCESS; + + return var_hdr->data; +} + +/** + * get_max_payload() - Get variable payload size from StandAloneMM. + * + * @size: size of the variable in storage + * Return: status code + */ +static efi_status_t get_max_payload(size_t *size) +{ + struct smm_variable_payload_size *var_payload = NULL; + size_t payload_size; + u8 *comm_buf = NULL; + efi_status_t ret; + + if (!size) + return EFI_INVALID_PARAMETER; + + payload_size = sizeof(*var_payload); + var_payload = setup_mm_hdr(&comm_buf, payload_size, + SMM_VARIABLE_FUNCTION_GET_PAYLOAD_SIZE, + &ret); + if (!var_payload) + return EFI_OUT_OF_RESOURCES; + + ret = mm_communicate(comm_buf, payload_size); + if (ret != EFI_SUCCESS) + goto out; + + /* Make sure the buffer is big enough for storing variables */ + if (var_payload->size < MM_VARIABLE_ACCESS_HEADER_SIZE + 0x20) { + ret = EFI_DEVICE_ERROR; + goto out; + } + *size = var_payload->size; + /* + * There seems to be a bug in EDK2 miscalculating the boundaries and + * size checks, so deduct 2 more bytes to fulfill this requirement. Fix + * it up here to ensure backwards compatibility with older versions + * (cf. StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c. + * sizeof (EFI_MM_COMMUNICATE_HEADER) instead the size minus the + * flexible array member). + * + * size is guaranteed to be > 2 due to checks on the beginning. + */ + *size -= 2; +out: + kfree(comm_buf); + return ret; +} + +static efi_status_t get_property_int(u16 *name, size_t name_size, + const efi_guid_t *vendor, + struct var_check_property *var_property) +{ + struct smm_variable_var_check_property *smm_property; + size_t payload_size; + u8 *comm_buf = NULL; + efi_status_t ret; + + memset(var_property, 0, sizeof(*var_property)); + payload_size = sizeof(*smm_property) + name_size; + if (payload_size > max_payload_size) + return EFI_INVALID_PARAMETER; + + smm_property = setup_mm_hdr( + &comm_buf, payload_size, + SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_GET, &ret); + if (!smm_property) + return EFI_OUT_OF_RESOURCES; + + memcpy(&smm_property->guid, vendor, sizeof(smm_property->guid)); + smm_property->name_size = name_size; + memcpy(smm_property->name, 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) + ret = EFI_SUCCESS; + if (ret != EFI_SUCCESS) + goto out; + memcpy(var_property, &smm_property->property, sizeof(*var_property)); + +out: + kfree(comm_buf); + return ret; +} + +static efi_status_t tee_get_variable(u16 *name, efi_guid_t *vendor, + u32 *attributes, unsigned long *data_size, + void *data) +{ + struct var_check_property var_property; + struct smm_variable_access *var_acc; + size_t payload_size; + size_t name_size; + size_t tmp_dsize; + u8 *comm_buf = NULL; + efi_status_t ret; + + if (!name || !vendor || !data_size) + return EFI_INVALID_PARAMETER; + + name_size = (ucs2_strnlen(name, EFI_VAR_NAME_LEN) + 1) * sizeof(u16); + if (name_size > max_payload_size - MM_VARIABLE_ACCESS_HEADER_SIZE) + return EFI_INVALID_PARAMETER; + + /* 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; + } + + payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + tmp_dsize; + var_acc = setup_mm_hdr(&comm_buf, payload_size, + SMM_VARIABLE_FUNCTION_GET_VARIABLE, &ret); + if (!var_acc) + return EFI_OUT_OF_RESOURCES; + + /* Fill in contents */ + memcpy(&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; + memcpy(var_acc->name, name, name_size); + + ret = mm_communicate(comm_buf, payload_size); + if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) + /* Update with reported data size for trimmed case */ + *data_size = var_acc->data_size; + if (ret != EFI_SUCCESS) + goto out; + + ret = get_property_int(name, name_size, vendor, &var_property); + if (ret != EFI_SUCCESS) + goto out; + + if (attributes) + *attributes = var_acc->attr; + + if (!data) { + ret = EFI_INVALID_PARAMETER; + goto out; + } + memcpy(data, (u8 *)var_acc->name + var_acc->name_size, + var_acc->data_size); +out: + kfree(comm_buf); + return ret; +} + +static efi_status_t tee_get_next_variable(unsigned long *name_size, + efi_char16_t *name, efi_guid_t *guid) +{ + struct smm_variable_getnext *var_getnext; + size_t payload_size; + size_t out_name_size; + size_t in_name_size; + u8 *comm_buf = NULL; + efi_status_t ret; + + if (!name_size || !name || !guid) + return EFI_INVALID_PARAMETER; + + out_name_size = *name_size; + in_name_size = (ucs2_strnlen(name, EFI_VAR_NAME_LEN) + 1) * sizeof(u16); + + if (out_name_size < in_name_size) + return EFI_INVALID_PARAMETER; + + if (in_name_size > max_payload_size - MM_VARIABLE_GET_NEXT_HEADER_SIZE) + return EFI_INVALID_PARAMETER; + + /* 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; + var_getnext = setup_mm_hdr(&comm_buf, payload_size, + SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME, + &ret); + if (!var_getnext) + return EFI_OUT_OF_RESOURCES; + + /* Fill in contents */ + memcpy(&var_getnext->guid, guid, sizeof(var_getnext->guid)); + var_getnext->name_size = out_name_size; + memcpy(var_getnext->name, name, in_name_size); + memset((u8 *)var_getnext->name + in_name_size, 0x0, + out_name_size - in_name_size); + + ret = mm_communicate(comm_buf, payload_size); + if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) { + /* Update with reported data size for trimmed case */ + *name_size = var_getnext->name_size; + } + if (ret != EFI_SUCCESS) + goto out; + + memcpy(guid, &var_getnext->guid, sizeof(*guid)); + memcpy(name, var_getnext->name, var_getnext->name_size); + +out: + kfree(comm_buf); + return ret; +} + +static efi_status_t tee_set_variable(efi_char16_t *name, efi_guid_t *vendor, + u32 attributes, unsigned long data_size, + void *data) +{ + efi_status_t ret; + struct var_check_property var_property; + struct smm_variable_access *var_acc; + size_t payload_size; + size_t name_size; + u8 *comm_buf = NULL; + + if (!name || name[0] == 0 || !vendor) + return EFI_INVALID_PARAMETER; + + if (data_size > 0 && !data) + return EFI_INVALID_PARAMETER; + + /* Check payload size */ + name_size = (ucs2_strnlen(name, EFI_VAR_NAME_LEN) + 1) * sizeof(u16); + payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + data_size; + if (payload_size > max_payload_size) + return EFI_INVALID_PARAMETER; + + /* + * Allocate the buffer early, before switching to RW (if needed) + * so we won't need to account for any failures in reading/setting + * the properties, if the allocation fails + */ + var_acc = setup_mm_hdr(&comm_buf, payload_size, + SMM_VARIABLE_FUNCTION_SET_VARIABLE, &ret); + if (!var_acc) + return EFI_OUT_OF_RESOURCES; + + /* + * The API has the ability to override RO flags. If no RO check was + * requested switch the variable to RW for the duration of this call + */ + ret = get_property_int(name, name_size, vendor, &var_property); + if (ret != EFI_SUCCESS) { + dev_err(pvt_data.dev, "Getting variable property failed\n"); + goto out; + } + + if (var_property.property & VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY) { + ret = EFI_WRITE_PROTECTED; + goto out; + } + + /* Fill in contents */ + memcpy(&var_acc->guid, vendor, sizeof(var_acc->guid)); + var_acc->data_size = data_size; + var_acc->name_size = name_size; + var_acc->attr = attributes; + memcpy(var_acc->name, name, name_size); + memcpy((u8 *)var_acc->name + name_size, data, data_size); + + ret = mm_communicate(comm_buf, payload_size); + dev_dbg(pvt_data.dev, "Set Variable %s %d %lx\n", __FILE__, __LINE__, ret); +out: + kfree(comm_buf); + return ret; +} + +static efi_status_t tee_set_variable_nonblocking(efi_char16_t *name, + efi_guid_t *vendor, + u32 attributes, + unsigned long data_size, + void *data) +{ + return EFI_UNSUPPORTED; +} + +static efi_status_t tee_query_variable_info(u32 attributes, + u64 *max_variable_storage_size, + u64 *remain_variable_storage_size, + u64 *max_variable_size) +{ + struct smm_variable_query_info *mm_query_info; + size_t payload_size; + efi_status_t ret; + u8 *comm_buf; + + payload_size = sizeof(*mm_query_info); + mm_query_info = setup_mm_hdr(&comm_buf, payload_size, + SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO, + &ret); + if (!mm_query_info) + return EFI_OUT_OF_RESOURCES; + + mm_query_info->attr = attributes; + ret = mm_communicate(comm_buf, payload_size); + if (ret != EFI_SUCCESS) + goto out; + *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; + +out: + kfree(comm_buf); + return ret; +} + +static void tee_stmm_efi_close_context(void *data) +{ + tee_client_close_context(pvt_data.ctx); +} + +static void tee_stmm_efi_close_session(void *data) +{ + tee_client_close_session(pvt_data.ctx, pvt_data.session); +} + +static void tee_stmm_restore_efivars_generic_ops(void) +{ + efivars_unregister(&tee_efivars); + efivars_generic_ops_register(); +} + +static int tee_stmm_efi_probe(struct device *dev) +{ + struct tee_ioctl_open_session_arg sess_arg; + efi_status_t ret; + int rc; + + pvt_data.ctx = tee_client_open_context(NULL, tee_ctx_match, NULL, NULL); + if (IS_ERR(pvt_data.ctx)) + return -ENODEV; + + rc = devm_add_action_or_reset(dev, tee_stmm_efi_close_context, NULL); + if (rc) + return rc; + + /* Open session with StMM PTA */ + memset(&sess_arg, 0, sizeof(sess_arg)); + export_uuid(sess_arg.uuid, &tee_stmm_efi_id_table[0].uuid); + rc = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL); + if ((rc < 0) || (sess_arg.ret != 0)) { + dev_err(dev, "tee_client_open_session failed, err: %x\n", + sess_arg.ret); + return -EINVAL; + } + pvt_data.session = sess_arg.session; + pvt_data.dev = dev; + rc = devm_add_action_or_reset(dev, tee_stmm_efi_close_session, NULL); + if (rc) + return rc; + + ret = get_max_payload(&max_payload_size); + if (ret != EFI_SUCCESS) + return -EIO; + + max_buffer_size = MM_COMMUNICATE_HEADER_SIZE + + MM_VARIABLE_COMMUNICATE_SIZE + + max_payload_size; + + tee_efivar_ops.get_variable = tee_get_variable; + tee_efivar_ops.get_next_variable = tee_get_next_variable; + tee_efivar_ops.set_variable = tee_set_variable; + tee_efivar_ops.set_variable_nonblocking = tee_set_variable_nonblocking; + tee_efivar_ops.query_variable_store = efi_query_variable_store; + tee_efivar_ops.query_variable_info = tee_query_variable_info; + + efivars_generic_ops_unregister(); + pr_info("Using TEE-based EFI runtime variable services\n"); + efivars_register(&tee_efivars, &tee_efivar_ops); + + return 0; +} + +static int tee_stmm_efi_remove(struct device *dev) +{ + tee_stmm_restore_efivars_generic_ops(); + + return 0; +} + +MODULE_DEVICE_TABLE(tee, tee_stmm_efi_id_table); + +static struct tee_client_driver tee_stmm_efi_driver = { + .id_table = tee_stmm_efi_id_table, + .driver = { + .name = "tee-stmm-efi", + .bus = &tee_bus_type, + .probe = tee_stmm_efi_probe, + .remove = tee_stmm_efi_remove, + }, +}; + +static int __init tee_stmm_efi_mod_init(void) +{ + return driver_register(&tee_stmm_efi_driver.driver); +} + +static void __exit tee_stmm_efi_mod_exit(void) +{ + driver_unregister(&tee_stmm_efi_driver.driver); +} + +module_init(tee_stmm_efi_mod_init); +module_exit(tee_stmm_efi_mod_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Ilias Apalodimas "); +MODULE_AUTHOR("Masahisa Kojima "); +MODULE_DESCRIPTION("TEE based EFI runtime variable service driver"); -- cgit v1.2.3 From 94f7f6182c72ba642c1f20111681f9cc8621c95f Mon Sep 17 00:00:00 2001 From: Masahisa Kojima Date: Tue, 7 Nov 2023 14:40:55 +0900 Subject: efivarfs: automatically update super block flag efivar operation is updated when the tee_stmm_efi module is probed. tee_stmm_efi module supports SetVariable runtime service, but user needs to manually remount the efivarfs as RW to enable the write access if the previous efivar operation does not support SetVariable and efivarfs is mounted as read-only. This commit notifies the update of efivar operation to efivarfs subsystem, then drops SB_RDONLY flag if the efivar operation supports SetVariable. Signed-off-by: Masahisa Kojima [ardb: use per-superblock instance of the notifier block] Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 6 ++++++ drivers/firmware/efi/vars.c | 8 ++++++++ fs/efivarfs/internal.h | 2 ++ fs/efivarfs/super.c | 27 +++++++++++++++++++++++++++ include/linux/efi.h | 8 ++++++++ 5 files changed, 51 insertions(+) (limited to 'drivers/firmware/efi') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 32a67c61c3b8..4fcda50acfa4 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -32,6 +32,7 @@ #include #include #include +#include #include @@ -187,6 +188,9 @@ static const struct attribute_group efi_subsys_attr_group = { .is_visible = efi_attr_is_visible, }; +struct blocking_notifier_head efivar_ops_nh; +EXPORT_SYMBOL_GPL(efivar_ops_nh); + static struct efivars generic_efivars; static struct efivar_operations generic_ops; @@ -431,6 +435,8 @@ static int __init efisubsys_init(void) platform_device_register_simple("efivars", 0, NULL, 0); } + BLOCKING_INIT_NOTIFIER_HEAD(&efivar_ops_nh); + error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); if (error) { pr_err("efi: Sysfs attribute export failed with error %d.\n", diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c index e9dc7116daf1..f654e6f6af87 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -63,6 +63,7 @@ int efivars_register(struct efivars *efivars, const struct efivar_operations *ops) { int rv; + int event; if (down_interruptible(&efivars_lock)) return -EINTR; @@ -77,6 +78,13 @@ int efivars_register(struct efivars *efivars, __efivars = efivars; + if (efivar_supports_writes()) + event = EFIVAR_OPS_RDWR; + else + event = EFIVAR_OPS_RDONLY; + + blocking_notifier_call_chain(&efivar_ops_nh, event, NULL); + pr_info("Registered efivars operations\n"); rv = 0; out: diff --git a/fs/efivarfs/internal.h b/fs/efivarfs/internal.h index 1dc0ccce3cc3..169252e6dc46 100644 --- a/fs/efivarfs/internal.h +++ b/fs/efivarfs/internal.h @@ -17,6 +17,8 @@ struct efivarfs_mount_opts { struct efivarfs_fs_info { struct efivarfs_mount_opts mount_opts; struct list_head efivarfs_list; + struct super_block *sb; + struct notifier_block nb; }; struct efi_variable { diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index cee325b5bbdd..6038dd39367a 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -15,10 +15,30 @@ #include #include #include +#include #include #include "internal.h" +static int efivarfs_ops_notifier(struct notifier_block *nb, unsigned long event, + void *data) +{ + struct efivarfs_fs_info *sfi = container_of(nb, struct efivarfs_fs_info, nb); + + switch (event) { + case EFIVAR_OPS_RDONLY: + sfi->sb->s_flags |= SB_RDONLY; + break; + case EFIVAR_OPS_RDWR: + sfi->sb->s_flags &= ~SB_RDONLY; + break; + default: + return NOTIFY_DONE; + } + + return NOTIFY_OK; +} + static void efivarfs_evict_inode(struct inode *inode) { clear_inode(inode); @@ -317,6 +337,12 @@ static int efivarfs_fill_super(struct super_block *sb, struct fs_context *fc) if (!root) return -ENOMEM; + sfi->sb = sb; + sfi->nb.notifier_call = efivarfs_ops_notifier; + err = blocking_notifier_chain_register(&efivar_ops_nh, &sfi->nb); + if (err) + return err; + err = efivar_init(efivarfs_callback, (void *)sb, true, &sfi->efivarfs_list); if (err) @@ -371,6 +397,7 @@ static void efivarfs_kill_sb(struct super_block *sb) { struct efivarfs_fs_info *sfi = sb->s_fs_info; + blocking_notifier_chain_unregister(&efivar_ops_nh, &sfi->nb); kill_litter_super(sb); /* Remove all entries and destroy */ diff --git a/include/linux/efi.h b/include/linux/efi.h index 3668aa204c47..c74f47711f0b 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1349,6 +1349,14 @@ bool efi_config_table_is_usable(const efi_guid_t *guid, unsigned long table) umode_t efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n); +/* + * efivar ops event type + */ +#define EFIVAR_OPS_RDONLY 0 +#define EFIVAR_OPS_RDWR 1 + +extern struct blocking_notifier_head efivar_ops_nh; + void efivars_generic_ops_register(void); void efivars_generic_ops_unregister(void); -- cgit v1.2.3 From 174a0c565cea74a7811ff79fbee1b70247570ade Mon Sep 17 00:00:00 2001 From: Wang Yao Date: Tue, 19 Dec 2023 17:14:05 +0800 Subject: efi/loongarch: Directly position the loaded image file The use of the 'kernel_offset' variable to position the image file that has been loaded by UEFI or GRUB is unnecessary, because we can directly position the loaded image file through using the image_base field of the efi_loaded_image struct provided by UEFI. Replace kernel_offset with image_base to position the image file that has been loaded by UEFI or GRUB. Signed-off-by: Wang Yao Signed-off-by: Ard Biesheuvel --- arch/loongarch/include/asm/efi.h | 2 -- arch/loongarch/kernel/head.S | 1 - arch/loongarch/kernel/image-vars.h | 1 - arch/loongarch/kernel/vmlinux.lds.S | 1 - drivers/firmware/efi/libstub/loongarch-stub.c | 9 +++++---- drivers/firmware/efi/libstub/loongarch-stub.h | 4 ++++ drivers/firmware/efi/libstub/loongarch.c | 6 ++++-- 7 files changed, 13 insertions(+), 11 deletions(-) create mode 100644 drivers/firmware/efi/libstub/loongarch-stub.h (limited to 'drivers/firmware/efi') diff --git a/arch/loongarch/include/asm/efi.h b/arch/loongarch/include/asm/efi.h index 91d81f9730ab..eddc8e79b3fa 100644 --- a/arch/loongarch/include/asm/efi.h +++ b/arch/loongarch/include/asm/efi.h @@ -32,6 +32,4 @@ static inline unsigned long efi_get_kimg_min_align(void) #define EFI_KIMG_PREFERRED_ADDRESS PHYSADDR(VMLINUX_LOAD_ADDRESS) -unsigned long kernel_entry_address(unsigned long kernel_addr); - #endif /* _ASM_LOONGARCH_EFI_H */ diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S index 53b883db0786..0ecab4216392 100644 --- a/arch/loongarch/kernel/head.S +++ b/arch/loongarch/kernel/head.S @@ -34,7 +34,6 @@ pe_header: SYM_DATA(kernel_asize, .long _kernel_asize); SYM_DATA(kernel_fsize, .long _kernel_fsize); -SYM_DATA(kernel_offset, .long _kernel_offset); #endif diff --git a/arch/loongarch/kernel/image-vars.h b/arch/loongarch/kernel/image-vars.h index 5087416b9678..41ddcf56d21c 100644 --- a/arch/loongarch/kernel/image-vars.h +++ b/arch/loongarch/kernel/image-vars.h @@ -11,7 +11,6 @@ __efistub_strcmp = strcmp; __efistub_kernel_entry = kernel_entry; __efistub_kernel_asize = kernel_asize; __efistub_kernel_fsize = kernel_fsize; -__efistub_kernel_offset = kernel_offset; #if defined(CONFIG_EFI_EARLYCON) || defined(CONFIG_SYSFB) __efistub_screen_info = screen_info; #endif diff --git a/arch/loongarch/kernel/vmlinux.lds.S b/arch/loongarch/kernel/vmlinux.lds.S index bb2ec86f37a8..a5d0cd2035da 100644 --- a/arch/loongarch/kernel/vmlinux.lds.S +++ b/arch/loongarch/kernel/vmlinux.lds.S @@ -143,7 +143,6 @@ SECTIONS _kernel_fsize = _edata - _text; _kernel_vsize = _end - __initdata_begin; _kernel_rsize = _edata - __initdata_begin; - _kernel_offset = kernel_offset - _text; #endif .gptab.sdata : { diff --git a/drivers/firmware/efi/libstub/loongarch-stub.c b/drivers/firmware/efi/libstub/loongarch-stub.c index d6ec5d4b8dbe..736b6aae323d 100644 --- a/drivers/firmware/efi/libstub/loongarch-stub.c +++ b/drivers/firmware/efi/libstub/loongarch-stub.c @@ -8,10 +8,10 @@ #include #include #include "efistub.h" +#include "loongarch-stub.h" extern int kernel_asize; extern int kernel_fsize; -extern int kernel_offset; extern int kernel_entry; efi_status_t handle_kernel_image(unsigned long *image_addr, @@ -24,7 +24,7 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, efi_status_t status; unsigned long kernel_addr = 0; - kernel_addr = (unsigned long)&kernel_offset - kernel_offset; + kernel_addr = (unsigned long)image->image_base; status = efi_relocate_kernel(&kernel_addr, kernel_fsize, kernel_asize, EFI_KIMG_PREFERRED_ADDRESS, efi_get_kimg_min_align(), 0x0); @@ -35,9 +35,10 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, return status; } -unsigned long kernel_entry_address(unsigned long kernel_addr) +unsigned long kernel_entry_address(unsigned long kernel_addr, + efi_loaded_image_t *image) { - unsigned long base = (unsigned long)&kernel_offset - kernel_offset; + unsigned long base = (unsigned long)image->image_base; return (unsigned long)&kernel_entry - base + kernel_addr; } diff --git a/drivers/firmware/efi/libstub/loongarch-stub.h b/drivers/firmware/efi/libstub/loongarch-stub.h new file mode 100644 index 000000000000..cd015955a015 --- /dev/null +++ b/drivers/firmware/efi/libstub/loongarch-stub.h @@ -0,0 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +unsigned long kernel_entry_address(unsigned long kernel_addr, + efi_loaded_image_t *image); diff --git a/drivers/firmware/efi/libstub/loongarch.c b/drivers/firmware/efi/libstub/loongarch.c index 0e0aa6cda73f..684c9354637c 100644 --- a/drivers/firmware/efi/libstub/loongarch.c +++ b/drivers/firmware/efi/libstub/loongarch.c @@ -8,6 +8,7 @@ #include #include #include "efistub.h" +#include "loongarch-stub.h" typedef void __noreturn (*kernel_entry_t)(bool efi, unsigned long cmdline, unsigned long systab); @@ -37,7 +38,8 @@ static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv) return EFI_SUCCESS; } -unsigned long __weak kernel_entry_address(unsigned long kernel_addr) +unsigned long __weak kernel_entry_address(unsigned long kernel_addr, + efi_loaded_image_t *image) { return *(unsigned long *)(kernel_addr + 8) - VMLINUX_LOAD_ADDRESS + kernel_addr; } @@ -73,7 +75,7 @@ efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image, csr_write64(CSR_DMW0_INIT, LOONGARCH_CSR_DMWIN0); csr_write64(CSR_DMW1_INIT, LOONGARCH_CSR_DMWIN1); - real_kernel_entry = (void *)kernel_entry_address(kernel_addr); + real_kernel_entry = (void *)kernel_entry_address(kernel_addr, image); real_kernel_entry(true, (unsigned long)cmdline_ptr, (unsigned long)efi_system_table); -- cgit v1.2.3 From 4afa688d7141ae7a166d32224abbfd536acccfca Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Thu, 21 Dec 2023 22:19:23 -0800 Subject: efi: memmap: fix kernel-doc warnings Correct all kernel-doc notation to repair warnings that are reported by scripts/kernel-doc: memmap.c:38: warning: No description found for return value of '__efi_memmap_init' memmap.c:82: warning: No description found for return value of 'efi_memmap_init_early' memmap.c:132: warning: Function parameter or member 'addr' not described in 'efi_memmap_init_late' memmap.c:132: warning: Excess function parameter 'phys_addr' description in 'efi_memmap_init_late' memmap.c:132: warning: No description found for return value of 'efi_memmap_init_late' Signed-off-by: Randy Dunlap Cc: Ard Biesheuvel Cc: linux-efi@vger.kernel.org Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/memmap.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'drivers/firmware/efi') diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c index a1180461a445..3365944f7965 100644 --- a/drivers/firmware/efi/memmap.c +++ b/drivers/firmware/efi/memmap.c @@ -32,7 +32,7 @@ * space isn't setup. Once the kernel is fully booted we can fallback * to the more robust memremap*() API. * - * Returns zero on success, a negative error code on failure. + * Returns: zero on success, a negative error code on failure. */ int __init __efi_memmap_init(struct efi_memory_map_data *data) { @@ -77,6 +77,8 @@ int __init __efi_memmap_init(struct efi_memory_map_data *data) * * Use early_memremap() to map the passed in EFI memory map and assign * it to efi.memmap. + * + * Returns: zero on success, a negative error code on failure. */ int __init efi_memmap_init_early(struct efi_memory_map_data *data) { @@ -107,7 +109,7 @@ void __init efi_memmap_unmap(void) /** * efi_memmap_init_late - Map efi.memmap with memremap() - * @phys_addr: Physical address of the new EFI memory map + * @addr: Physical address of the new EFI memory map * @size: Size in bytes of the new EFI memory map * * Setup a mapping of the EFI memory map using ioremap_cache(). This @@ -126,7 +128,7 @@ void __init efi_memmap_unmap(void) * runtime so that things like efi_mem_desc_lookup() and * efi_mem_attributes() always work. * - * Returns zero on success, a negative error code on failure. + * Returns: zero on success, a negative error code on failure. */ int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size) { -- cgit v1.2.3