From 60305db9884515ca063474e262b454f6da04e4e2 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 22 Jan 2015 10:01:40 +0000 Subject: [PATCH] arm64/efi: move virtmap init to early initcall Now that the create_mapping() code in mm/mmu.c is able to support setting up kernel page tables at initcall time, we can move the whole virtmap creation to arm64_enable_runtime_services() instead of having a distinct stage during early boot. This also allows us to drop the arm64-specific EFI_VIRTMAP flag. Signed-off-by: Ard Biesheuvel Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/efi.h | 18 ++---- arch/arm64/kernel/efi.c | 111 +++++++++++++++++------------------ arch/arm64/kernel/setup.c | 1 - arch/arm64/mm/mmu.c | 2 +- 4 files changed, 59 insertions(+), 73 deletions(-) diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h index 7baf2cc04e1e..ef572206f1c3 100644 --- a/arch/arm64/include/asm/efi.h +++ b/arch/arm64/include/asm/efi.h @@ -6,10 +6,8 @@ #ifdef CONFIG_EFI extern void efi_init(void); -extern void efi_virtmap_init(void); #else #define efi_init() -#define efi_virtmap_init() #endif #define efi_call_virt(f, ...) \ @@ -53,23 +51,17 @@ extern void efi_virtmap_init(void); #define EFI_ALLOC_ALIGN SZ_64K /* - * On ARM systems, virtually remapped UEFI runtime services are set up in three + * On ARM systems, virtually remapped UEFI runtime services are set up in two * distinct stages: * - The stub retrieves the final version of the memory map from UEFI, populates * the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime * service to communicate the new mapping to the firmware (Note that the new * mapping is not live at this time) - * - During early boot, the page tables are allocated and populated based on the - * virt_addr fields in the memory map, but only if all descriptors with the - * EFI_MEMORY_RUNTIME attribute have a non-zero value for virt_addr. If this - * succeeds, the EFI_VIRTMAP flag is set to indicate that the virtual mappings - * have been installed successfully. - * - During an early initcall(), the UEFI Runtime Services are enabled and the - * EFI_RUNTIME_SERVICES bit set if some conditions are met, i.e., we need a - * non-early mapping of the UEFI system table, and we need to have the virtmap - * installed. + * - During an early initcall(), the EFI system table is permanently remapped + * and the virtual remapping of the UEFI Runtime Services regions is loaded + * into a private set of page tables. If this all succeeds, the Runtime + * Services are enabled and the EFI_RUNTIME_SERVICES bit set. */ -#define EFI_VIRTMAP EFI_ARCH_1 void efi_virtmap_load(void); void efi_virtmap_unload(void); diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index c9cb0fbe7aa4..b42c7b480e1e 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -38,6 +38,19 @@ struct efi_memory_map memmap; static u64 efi_system_table; +static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss; + +static struct mm_struct efi_mm = { + .mm_rb = RB_ROOT, + .pgd = efi_pgd, + .mm_users = ATOMIC_INIT(2), + .mm_count = ATOMIC_INIT(1), + .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), + .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), + .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), + INIT_MM_CONTEXT(efi_mm) +}; + static int uefi_debug __initdata; static int __init uefi_debug_setup(char *str) { @@ -213,6 +226,45 @@ void __init efi_init(void) return; reserve_regions(); + early_memunmap(memmap.map, params.mmap_size); +} + +static bool __init efi_virtmap_init(void) +{ + efi_memory_desc_t *md; + + for_each_efi_memory_desc(&memmap, md) { + u64 paddr, npages, size; + pgprot_t prot; + + if (!(md->attribute & EFI_MEMORY_RUNTIME)) + continue; + if (md->virt_addr == 0) + return false; + + paddr = md->phys_addr; + npages = md->num_pages; + memrange_efi_to_native(&paddr, &npages); + size = npages << PAGE_SHIFT; + + pr_info(" EFI remap 0x%016llx => %p\n", + md->phys_addr, (void *)md->virt_addr); + + /* + * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be + * executable, everything else can be mapped with the XN bits + * set. + */ + if (!is_normal_ram(md)) + prot = __pgprot(PROT_DEVICE_nGnRE); + else if (md->type == EFI_RUNTIME_SERVICES_CODE) + prot = PAGE_KERNEL_EXEC; + else + prot = PAGE_KERNEL; + + create_pgd_mapping(&efi_mm, paddr, md->virt_addr, size, prot); + } + return true; } /* @@ -254,7 +306,7 @@ static int __init arm64_enable_runtime_services(void) } set_bit(EFI_SYSTEM_TABLES, &efi.flags); - if (!efi_enabled(EFI_VIRTMAP)) { + if (!efi_virtmap_init()) { pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n"); return -1; } @@ -283,19 +335,6 @@ static int __init arm64_dmi_init(void) } core_initcall(arm64_dmi_init); -static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss; - -static struct mm_struct efi_mm = { - .mm_rb = RB_ROOT, - .pgd = efi_pgd, - .mm_users = ATOMIC_INIT(2), - .mm_count = ATOMIC_INIT(1), - .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), - .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), - .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), - INIT_MM_CONTEXT(efi_mm) -}; - static void efi_set_pgd(struct mm_struct *mm) { cpu_switch_mm(mm->pgd, mm); @@ -315,47 +354,3 @@ void efi_virtmap_unload(void) efi_set_pgd(current->active_mm); preempt_enable(); } - -void __init efi_virtmap_init(void) -{ - efi_memory_desc_t *md; - - if (!efi_enabled(EFI_BOOT)) - return; - - for_each_efi_memory_desc(&memmap, md) { - u64 paddr, npages, size; - pgprot_t prot; - - if (!(md->attribute & EFI_MEMORY_RUNTIME)) - continue; - if (WARN(md->virt_addr == 0, - "UEFI virtual mapping incomplete or missing -- no entry found for 0x%llx\n", - md->phys_addr)) - return; - - paddr = md->phys_addr; - npages = md->num_pages; - memrange_efi_to_native(&paddr, &npages); - size = npages << PAGE_SHIFT; - - pr_info(" EFI remap 0x%016llx => %p\n", - md->phys_addr, (void *)md->virt_addr); - - /* - * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be - * executable, everything else can be mapped with the XN bits - * set. - */ - if (!is_normal_ram(md)) - prot = __pgprot(PROT_DEVICE_nGnRE); - else if (md->type == EFI_RUNTIME_SERVICES_CODE) - prot = PAGE_KERNEL_EXEC; - else - prot = PAGE_KERNEL; - - create_pgd_mapping(&efi_mm, paddr, md->virt_addr, size, prot); - } - set_bit(EFI_VIRTMAP, &efi.flags); - early_memunmap(memmap.map, memmap.map_end - memmap.map); -} diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 207413fe08a0..bb10903887d4 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -382,7 +382,6 @@ void __init setup_arch(char **cmdline_p) paging_init(); request_standard_resources(); - efi_virtmap_init(); early_ioremap_reset(); unflatten_device_tree(); diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 91d55b6efd8a..155cbb0a74b6 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -269,7 +269,7 @@ void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, pgprot_t prot) { __create_mapping(mm, pgd_offset(mm, virt), phys, virt, size, prot, - early_alloc); + late_alloc); } static void create_mapping_late(phys_addr_t phys, unsigned long virt, -- GitLab