From 732ea9db9d8a6a0444d18ed810cccb2428d8766b Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Tue, 11 Oct 2022 17:10:39 +0200 Subject: efi: libstub: Move screen_info handling to common code Currently, arm64, RISC-V and LoongArch rely on the fact that struct screen_info can be accessed directly, due to the fact that the EFI stub and the core kernel are part of the same image. This will change after a future patch, so let's ensure that the screen_info handling is able to deal with this, by adopting the arm32 approach of passing it as a configuration table. While at it, switch to ACPI reclaim memory to hold the screen_info data, which is more appropriate for this kind of allocation. Signed-off-by: Ard Biesheuvel --- arch/arm/include/asm/efi.h | 3 -- arch/arm/kernel/efi.c | 31 +++-------------- arch/arm64/include/asm/efi.h | 6 ---- arch/loongarch/include/asm/efi.h | 9 ----- arch/loongarch/kernel/efi.c | 24 +++++++++++-- arch/riscv/include/asm/efi.h | 6 ---- drivers/firmware/efi/efi-init.c | 21 +++++++++-- drivers/firmware/efi/efi.c | 5 +++ drivers/firmware/efi/libstub/Makefile | 3 +- drivers/firmware/efi/libstub/arm32-stub.c | 37 -------------------- drivers/firmware/efi/libstub/efi-stub.c | 9 +++++ drivers/firmware/efi/libstub/efistub.h | 3 ++ drivers/firmware/efi/libstub/screen_info.c | 56 ++++++++++++++++++++++++++++++ include/linux/efi.h | 2 +- 14 files changed, 121 insertions(+), 94 deletions(-) create mode 100644 drivers/firmware/efi/libstub/screen_info.c diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h index 4bdd930167c0..b95241b1ca65 100644 --- a/arch/arm/include/asm/efi.h +++ b/arch/arm/include/asm/efi.h @@ -43,9 +43,6 @@ void efi_virtmap_unload(void); /* arch specific definitions used by the stub code */ -struct screen_info *alloc_screen_info(void); -void free_screen_info(struct screen_info *si); - /* * A reasonable upper bound for the uncompressed kernel size is 32 MBytes, * so we will reserve that amount of memory. We have no easy way to tell what diff --git a/arch/arm/kernel/efi.c b/arch/arm/kernel/efi.c index e50ad7eefc02..882104f43b3b 100644 --- a/arch/arm/kernel/efi.c +++ b/arch/arm/kernel/efi.c @@ -75,38 +75,13 @@ int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md) return 0; } -static unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR; static unsigned long __initdata cpu_state_table = EFI_INVALID_TABLE_ADDR; const efi_config_table_type_t efi_arch_tables[] __initconst = { - {LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID, &screen_info_table}, {LINUX_EFI_ARM_CPU_STATE_TABLE_GUID, &cpu_state_table}, {} }; -static void __init load_screen_info_table(void) -{ - struct screen_info *si; - - if (screen_info_table != EFI_INVALID_TABLE_ADDR) { - si = early_memremap_ro(screen_info_table, sizeof(*si)); - if (!si) { - pr_err("Could not map screen_info config table\n"); - return; - } - screen_info = *si; - early_memunmap(si, sizeof(*si)); - - /* dummycon on ARM needs non-zero values for columns/lines */ - screen_info.orig_video_cols = 80; - screen_info.orig_video_lines = 25; - - if (memblock_is_map_memory(screen_info.lfb_base)) - memblock_mark_nomap(screen_info.lfb_base, - screen_info.lfb_size); - } -} - static void __init load_cpu_state_table(void) { if (cpu_state_table != EFI_INVALID_TABLE_ADDR) { @@ -145,7 +120,11 @@ void __init arm_efi_init(void) { efi_init(); - load_screen_info_table(); + if (screen_info.orig_video_isVGA == VIDEO_TYPE_EFI) { + /* dummycon on ARM needs non-zero values for columns/lines */ + screen_info.orig_video_cols = 80; + screen_info.orig_video_lines = 25; + } /* ARM does not permit early mappings to persist across paging_init() */ efi_memmap_unmap(); diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h index d6cf535d8352..8604473a85b8 100644 --- a/arch/arm64/include/asm/efi.h +++ b/arch/arm64/include/asm/efi.h @@ -84,12 +84,6 @@ static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr) return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS_MIN - 1)); } -#define alloc_screen_info(x...) &screen_info - -static inline void free_screen_info(struct screen_info *si) -{ -} - #define EFI_ALLOC_ALIGN SZ_64K /* diff --git a/arch/loongarch/include/asm/efi.h b/arch/loongarch/include/asm/efi.h index 174567b00ddb..60d6a170c18d 100644 --- a/arch/loongarch/include/asm/efi.h +++ b/arch/loongarch/include/asm/efi.h @@ -19,15 +19,6 @@ void efifb_setup_from_dmi(struct screen_info *si, const char *opt); #define EFI_ALLOC_ALIGN SZ_64K #define EFI_RT_VIRTUAL_OFFSET CSR_DMW0_BASE -static inline struct screen_info *alloc_screen_info(void) -{ - return &screen_info; -} - -static inline void free_screen_info(struct screen_info *si) -{ -} - static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr) { return ULONG_MAX; diff --git a/arch/loongarch/kernel/efi.c b/arch/loongarch/kernel/efi.c index a31329971133..d75ce73e8ff8 100644 --- a/arch/loongarch/kernel/efi.c +++ b/arch/loongarch/kernel/efi.c @@ -52,6 +52,27 @@ void __init efi_runtime_init(void) set_bit(EFI_RUNTIME_SERVICES, &efi.flags); } +unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR; + +static void __init init_screen_info(void) +{ + struct screen_info *si; + + if (screen_info_table == EFI_INVALID_TABLE_ADDR) + return; + + si = early_memremap(screen_info_table, sizeof(*si)); + if (!si) { + pr_err("Could not map screen_info config table\n"); + return; + } + screen_info = *si; + memset(si, 0, sizeof(*si)); + early_memunmap(si, sizeof(*si)); + + memblock_reserve(screen_info.lfb_base, screen_info.lfb_size); +} + void __init efi_init(void) { int size; @@ -80,8 +101,7 @@ void __init efi_init(void) set_bit(EFI_CONFIG_TABLES, &efi.flags); - if (screen_info.orig_video_isVGA == VIDEO_TYPE_EFI) - memblock_reserve(screen_info.lfb_base, screen_info.lfb_size); + init_screen_info(); if (boot_memmap == EFI_INVALID_TABLE_ADDR) return; diff --git a/arch/riscv/include/asm/efi.h b/arch/riscv/include/asm/efi.h index f74879a8f1ea..d0570936cb8c 100644 --- a/arch/riscv/include/asm/efi.h +++ b/arch/riscv/include/asm/efi.h @@ -31,12 +31,6 @@ static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr) return ULONG_MAX; } -#define alloc_screen_info(x...) (&screen_info) - -static inline void free_screen_info(struct screen_info *si) -{ -} - void efi_virtmap_load(void); void efi_virtmap_unload(void); diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c index 2fd770b499a3..1639159493e3 100644 --- a/drivers/firmware/efi/efi-init.c +++ b/drivers/firmware/efi/efi-init.c @@ -22,6 +22,8 @@ #include +unsigned long __initdata screen_info_table = EFI_INVALID_TABLE_ADDR; + static int __init is_memory(efi_memory_desc_t *md) { if (md->attribute & (EFI_MEMORY_WB|EFI_MEMORY_WT|EFI_MEMORY_WC)) @@ -55,9 +57,22 @@ extern __weak const efi_config_table_type_t efi_arch_tables[]; static void __init init_screen_info(void) { - if (screen_info.orig_video_isVGA == VIDEO_TYPE_EFI && - memblock_is_map_memory(screen_info.lfb_base)) - memblock_mark_nomap(screen_info.lfb_base, screen_info.lfb_size); + struct screen_info *si; + + if (screen_info_table != EFI_INVALID_TABLE_ADDR) { + si = early_memremap(screen_info_table, sizeof(*si)); + if (!si) { + pr_err("Could not map screen_info config table\n"); + return; + } + screen_info = *si; + memset(si, 0, sizeof(*si)); + early_memunmap(si, sizeof(*si)); + + if (memblock_is_map_memory(screen_info.lfb_base)) + memblock_mark_nomap(screen_info.lfb_base, + screen_info.lfb_size); + } } static int __init uefi_init(u64 efi_system_table) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index a46df5d1d094..951a42d27cf4 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -58,6 +58,8 @@ static unsigned long __initdata mem_reserve = EFI_INVALID_TABLE_ADDR; static unsigned long __initdata rt_prop = EFI_INVALID_TABLE_ADDR; static unsigned long __initdata initrd = EFI_INVALID_TABLE_ADDR; +extern unsigned long screen_info_table; + struct mm_struct efi_mm = { .mm_mt = MTREE_INIT_EXT(mm_mt, MM_MT_FLAGS, efi_mm.mmap_lock), .mm_users = ATOMIC_INIT(2), @@ -546,6 +548,9 @@ static const efi_config_table_type_t common_tables[] __initconst = { #endif #ifdef CONFIG_EFI_COCO_SECRET {LINUX_EFI_COCO_SECRET_AREA_GUID, &efi.coco_secret, "CocoSecret" }, +#endif +#ifdef CONFIG_EFI_GENERIC_STUB + {LINUX_EFI_SCREEN_INFO_TABLE_GUID, &screen_info_table }, #endif {}, }; diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 5b0ae755180e..3f44e272ff9c 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -81,7 +81,8 @@ lib-$(CONFIG_EFI_PARAMS_FROM_FDT) += fdt.o \ $(obj)/lib-%.o: $(srctree)/lib/%.c FORCE $(call if_changed_rule,cc_o_c) -lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o string.o intrinsics.o systable.o +lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o string.o intrinsics.o systable.o \ + screen_info.o lib-$(CONFIG_ARM) += arm32-stub.o lib-$(CONFIG_ARM64) += arm64-stub.o arm64-entry.o diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c index 0131e3aaa605..1073dd947516 100644 --- a/drivers/firmware/efi/libstub/arm32-stub.c +++ b/drivers/firmware/efi/libstub/arm32-stub.c @@ -76,43 +76,6 @@ void efi_handle_post_ebs_state(void) &efi_entry_state->sctlr_after_ebs); } -static efi_guid_t screen_info_guid = LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID; - -struct screen_info *alloc_screen_info(void) -{ - struct screen_info *si; - efi_status_t status; - - /* - * Unlike on arm64, where we can directly fill out the screen_info - * structure from the stub, we need to allocate a buffer to hold - * its contents while we hand over to the kernel proper from the - * decompressor. - */ - status = efi_bs_call(allocate_pool, EFI_RUNTIME_SERVICES_DATA, - sizeof(*si), (void **)&si); - - if (status != EFI_SUCCESS) - return NULL; - - status = efi_bs_call(install_configuration_table, - &screen_info_guid, si); - if (status == EFI_SUCCESS) - return si; - - efi_bs_call(free_pool, si); - return NULL; -} - -void free_screen_info(struct screen_info *si) -{ - if (!si) - return; - - efi_bs_call(install_configuration_table, &screen_info_guid, NULL); - efi_bs_call(free_pool, si); -} - efi_status_t handle_kernel_image(unsigned long *image_addr, unsigned long *image_size, unsigned long *reserve_addr, diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c index b55d1009d4c8..8521dc09c6ae 100644 --- a/drivers/firmware/efi/libstub/efi-stub.c +++ b/drivers/firmware/efi/libstub/efi-stub.c @@ -47,6 +47,15 @@ static u64 virtmap_base = EFI_RT_VIRTUAL_BASE; static bool flat_va_mapping = (EFI_RT_VIRTUAL_OFFSET != 0); +struct screen_info * __weak alloc_screen_info(void) +{ + return &screen_info; +} + +void __weak free_screen_info(struct screen_info *si) +{ +} + static struct screen_info *setup_graphics(void) { efi_guid_t gop_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID; diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index a30fb5d8ef05..a4cb51e2cae3 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -975,4 +975,7 @@ efi_enable_reset_attack_mitigation(void) { } void efi_retrieve_tpm2_eventlog(void); +struct screen_info *alloc_screen_info(void); +void free_screen_info(struct screen_info *si); + #endif diff --git a/drivers/firmware/efi/libstub/screen_info.c b/drivers/firmware/efi/libstub/screen_info.c new file mode 100644 index 000000000000..8e76a8b384ba --- /dev/null +++ b/drivers/firmware/efi/libstub/screen_info.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include + +#include "efistub.h" + +/* + * There are two ways of populating the core kernel's struct screen_info via the stub: + * - using a configuration table, like below, which relies on the EFI init code + * to locate the table and copy the contents; + * - by linking directly to the core kernel's copy of the global symbol. + * + * The latter is preferred because it makes the EFIFB earlycon available very + * early, but it only works if the EFI stub is part of the core kernel image + * itself. The zboot decompressor can only use the configuration table + * approach. + * + * In order to support both methods from the same build of the EFI stub + * library, provide this dummy global definition of struct screen_info. If it + * is required to satisfy a link dependency, it means we need to override the + * __weak alloc and free methods with the ones below, and those will be pulled + * in as well. + */ +struct screen_info screen_info; + +static efi_guid_t screen_info_guid = LINUX_EFI_SCREEN_INFO_TABLE_GUID; + +struct screen_info *alloc_screen_info(void) +{ + struct screen_info *si; + efi_status_t status; + + status = efi_bs_call(allocate_pool, EFI_ACPI_RECLAIM_MEMORY, + sizeof(*si), (void **)&si); + + if (status != EFI_SUCCESS) + return NULL; + + status = efi_bs_call(install_configuration_table, + &screen_info_guid, si); + if (status == EFI_SUCCESS) + return si; + + efi_bs_call(free_pool, si); + return NULL; +} + +void free_screen_info(struct screen_info *si) +{ + if (!si) + return; + + efi_bs_call(install_configuration_table, &screen_info_guid, NULL); + efi_bs_call(free_pool, si); +} diff --git a/include/linux/efi.h b/include/linux/efi.h index 929d559ad41d..dfa6cc8bbef9 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -403,7 +403,7 @@ void efi_native_runtime_setup(void); * structure that was populated by the stub based on the GOP protocol instance * associated with ConOut */ -#define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95) +#define LINUX_EFI_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95) #define LINUX_EFI_ARM_CPU_STATE_TABLE_GUID EFI_GUID(0xef79e4aa, 0x3c3d, 0x4989, 0xb9, 0x02, 0x07, 0xa9, 0x43, 0xe5, 0x50, 0xd2) #define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f) #define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b) -- cgit