// SPDX-License-Identifier: GPL-2.0 /* * x86_64 specific EFI support functions * Based on Extensible Firmware Interface Specification version 1.0 * * Copyright (C) 2005-2008 Intel Co. * Fenghua Yu * Bibo Mao * Chandramouli Narayanan * Huang Ying * * Code to convert EFI to E820 map has been implemented in elilo bootloader * based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table * is setup appropriately for EFI runtime code. * - mouli 06/14/2007. * */ #define pr_fmt(fmt) "efi: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * We allocate runtime services regions top-down, starting from -4G, i.e. * 0xffff_ffff_0000_0000 and limit EFI VA mapping space to 64G. */ static u64 efi_va = EFI_VA_START; struct efi_scratch efi_scratch; EXPORT_SYMBOL_GPL(efi_mm); /* * We need our own copy of the higher levels of the page tables * because we want to avoid inserting EFI region mappings (EFI_VA_END * to EFI_VA_START) into the standard kernel page tables. Everything * else can be shared, see efi_sync_low_kernel_mappings(). * * We don't want the pgd on the pgd_list and cannot use pgd_alloc() for the * allocation. */ int __init efi_alloc_page_tables(void) { pgd_t *pgd, *efi_pgd; p4d_t *p4d; pud_t *pud; gfp_t gfp_mask; if (efi_have_uv1_memmap()) return 0; gfp_mask = GFP_KERNEL | __GFP_ZERO; efi_pgd = (pgd_t *)__get_free_pages(gfp_mask, PGD_ALLOCATION_ORDER); if (!efi_pgd) return -ENOMEM; pgd = efi_pgd + pgd_index(EFI_VA_END); p4d = p4d_alloc(&init_mm, pgd, EFI_VA_END); if (!p4d) { free_page((unsigned long)efi_pgd); return -ENOMEM; } pud = pud_alloc(&init_mm, p4d, EFI_VA_END); if (!pud) { if (pgtable_l5_enabled()) free_page((unsigned long) pgd_page_vaddr(*pgd)); free_pages((unsigned long)efi_pgd, PGD_ALLOCATION_ORDER); return -ENOMEM; } efi_mm.pgd = efi_pgd; mm_init_cpumask(&efi_mm); init_new_context(NULL, &efi_mm); return 0; } /* * Add low kernel mappings for passing arguments to EFI functions. */ void efi_sync_low_kernel_mappings(void) { unsigned num_entries; pgd_t *pgd_k, *pgd_efi; p4d_t *p4d_k, *p4d_efi; pud_t *pud_k, *pud_efi; pgd_t *efi_pgd = efi_mm.pgd; if (efi_have_uv1_memmap()) return; /* * We can share all PGD entries apart from the one entry that * covers the EFI runtime mapping space. * * Make sure the EFI runtime region mappings are guaranteed to * only span a single PGD entry and that the entry also maps * other important kernel regions. */ MAYBE_BUILD_BUG_ON(pgd_index(EFI_VA_END) != pgd_index(MODULES_END)); MAYBE_BUILD_BUG_ON((EFI_VA_START & PGDIR_MASK) != (EFI_VA_END & PGDIR_MASK)); pgd_efi = efi_pgd + pgd_index(PAGE_OFFSET); pgd_k = pgd_offset_k(PAGE_OFFSET); num_entries = pgd_index(EFI_VA_END) - pgd_index(PAGE_OFFSET); memcpy(pgd_efi, pgd_k, sizeof(pgd_t) * num_entries); /* * As with PGDs, we share all P4D entries apart from the one entry * that covers the EFI runtime mapping space. */ BUILD_BUG_ON(p4d_index(EFI_VA_END) != p4d_index(MODULES_END)); BUILD_BUG_ON((EFI_VA_START & P4D_MASK) != (EFI_VA_END & P4D_MASK)); pgd_efi = efi_pgd + pgd_index(EFI_VA_END); pgd_k = pgd_offset_k(EFI_VA_END); p4d_efi = p4d_offset(pgd_efi, 0); p4d_k = p4d_offset(pgd_k, 0); num_entries = p4d_index(EFI_VA_END); memcpy(p4d_efi, p4d_k, sizeof(p4d_t) * num_entries); /* * We share all the PUD entries apart from those that map the * EFI regions. Copy around them. */ BUILD_BUG_ON((EFI_VA_START & ~PUD_MASK) != 0); BUILD_BUG_ON((EFI_VA_END & ~PUD_MASK) != 0); p4d_efi = p4d_offset(pgd_efi, EFI_VA_END); p4d_k = p4d_offset(pgd_k, EFI_VA_END); pud_efi = pud_offset(p4d_efi, 0); pud_k = pud_offset(p4d_k, 0); num_entries = pud_index(EFI_VA_END); memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries); pud_efi = pud_offset(p4d_efi, EFI_VA_START); pud_k = pud_offset(p4d_k, EFI_VA_START); num_entries = PTRS_PER_PUD - pud_index(EFI_VA_START); memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries); } /* * Wrapper for slow_virt_to_phys() that handles NULL addresses. */ static inline phys_addr_t virt_to_phys_or_null_size(void *va, unsigned long size) { phys_addr_t pa; if (!va) return 0; if (virt_addr_valid(va)) return virt_to_phys(va); pa = slow_virt_to_phys(va); /* check if the object crosses a page boundary */ if (WARN_ON((pa ^ (pa + size - 1)) & PAGE_MASK)) return 0; return pa; } #define virt_to_phys_or_null(addr) \ virt_to_phys_or_null_size((addr), sizeof(*(addr))) int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) { unsigned long pfn, text, pf; struct page *page; unsigned npages; pgd_t *pgd = efi_mm.pgd; if (efi_have_uv1_memmap()) return 0; /* * It can happen that the physical address of new_memmap lands in memory * which is not mapped in the EFI page table. Therefore we need to go * and ident-map those pages containing the map before calling * phys_efi_set_virtual_address_map(). */ pfn = pa_memmap >> PAGE_SHIFT; pf = _PAGE_NX | _PAGE_RW | _PAGE_ENC; if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, pf)) { pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap); return 1; } /* * Certain firmware versions are way too sentimential and still believe * they are exclusive and unquestionable owners of the first physical page, * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY * (but then write-access it later during SetVirtualAddressMap()). * * Create a 1:1 mapping for this page, to avoid triple faults during early * boot with such firmware. We are free to hand this page to the BIOS, * as trim_bios_range() will reserve the first page and isolate it away * from memory allocators anyway. */ if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, pf)) { pr_err("Failed to create 1:1 mapping for the first page!\n"); return 1; } /* * When making calls to the firmware everything needs to be 1:1 * mapped and addressable with 32-bit pointers. Map the kernel * text and allocate a new stack because we can't rely on the * stack pointer being < 4GB. */ if (!efi_is_mixed()) return 0; page = alloc_page(GFP_KERNEL|__GFP_DMA32); if (!page) { pr_err("Unable to allocate EFI runtime stack < 4GB\n"); return 1; } efi_scratch.phys_stack = page_to_phys(page + 1); /* stack grows down */ npages = (__end_rodata_aligned - _text) >> PAGE_SHIFT; text = __pa(_text); pfn = text >> PAGE_SHIFT; pf = _PAGE_ENC; if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, pf)) { pr_err("Failed to map kernel text 1:1\n"); return 1; } return 0; } static void __init __map_region(efi_memory_desc_t *md, u64 va) { unsigned long flags = _PAGE_RW; unsigned long pfn; pgd_t *pgd = efi_mm.pgd; /* * EFI_RUNTIME_SERVICES_CODE regions typically cover PE/COFF * executable images in memory that consist of both R-X and * RW- sections, so we cannot apply read-only or non-exec * permissions just yet. However, modern EFI systems provide * a memory attributes table that describes those sections * with the appropriate restricted permissions, which are * applied in efi_runtime_update_mappings() below. All other * regions can be mapped non-executable at this point, with * the exception of boot services code regions, but those will * be unmapped again entirely in efi_free_boot_services(). */ if (md->type != EFI_BOOT_SERVICES_CODE && md->type != EFI_RUNTIME_SERVICES_CODE) flags |= _PAGE_NX; if (!(md->attribute & EFI_MEMORY_WB)) flags |= _PAGE_PCD; if (sev_active() && md->type != EFI_MEMORY_MAPPED_IO) flags |= _PAGE_ENC; pfn = md->phys_addr >> PAGE_SHIFT; if (kernel_map_pages_in_pgd(pgd, pfn, va, md->num_pages, flags)) pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n", md->phys_addr, va); } void __init efi_map_region(efi_memory_desc_t *md) { unsigned long size = md->num_pages << PAGE_SHIFT; u64 pa = md->phys_addr; if (efi_have_uv1_memmap()) return old_map_region(md); /* * Make sure the 1:1 mappings are present as a catch-all for b0rked * firmware which doesn't update all internal pointers after switching * to virtual mode and would otherwise crap on us. */ __map_region(md, md->phys_addr); /* * Enforce the 1:1 mapping as the default virtual address when * booting in EFI mixed mode, because even though we may be * running a 64-bit kernel, the firmware may only be 32-bit. */ if (efi_is_mixed()) { md->virt_addr = md->phys_addr; return; } efi_va -= size; /* Is PA 2M-aligned? */ if (!(pa & (PMD_SIZE - 1))) { efi_va &= PMD_MASK; } else { u64 pa_offset = pa & (PMD_SIZE - 1); u64 prev_va = efi_va; /* get us the same offset within this 2M page */ efi_va = (efi_va & PMD_MASK) + pa_offset; if (efi_va > prev_va) efi_va -= PMD_SIZE; } if (efi_va < EFI_VA_END) { pr_warn(FW_WARN "VA address range overflow!\n"); return; } /* Do the VA map */ __map_region(md, efi_va); md->virt_addr = efi_va; } /* * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges. * md->virt_addr is the original virtual address which had been mapped in kexec * 1st kernel. */ void __init efi_map_region_fixed(efi_memory_desc_t *md) { __map_region(md, md->phys_addr); __map_region(md, md->virt_addr); } void __init parse_efi_setup(u64 phys_addr, u32 data_len) { efi_setup = phys_addr + sizeof(struct setup_data); } static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf) { unsigned long pfn; pgd_t *pgd = efi_mm.pgd; int err1, err2; /* Update the 1:1 mapping */ pfn = md->phys_addr >> PAGE_SHIFT; err1 = kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf); if (err1) { pr_err("Error while updating 1:1 mapping PA 0x%llx -> VA 0x%llx!\n", md->phys_addr, md->virt_addr); } err2 = kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf); if (err2) { pr_err("Error while updating VA mapping PA 0x%llx -> VA 0x%llx!\n", md->phys_addr, md->virt_addr); } return err1 || err2; } static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md) { unsigned long pf = 0; if (md->attribute & EFI_MEMORY_XP) pf |= _PAGE_NX; if (!(md->attribute & EFI_MEMORY_RO)) pf |= _PAGE_RW; if (sev_active()) pf |= _PAGE_ENC; return efi_update_mappings(md, pf); } void __init efi_runtime_update_mappings(void) { efi_memory_desc_t *md; if (efi_have_uv1_memmap()) { if (__supported_pte_mask & _PAGE_NX) runtime_code_page_mkexec(); return; } /* * Use the EFI Memory Attribute Table for mapping permissions if it * exists, since it is intended to supersede EFI_PROPERTIES_TABLE. */ if (efi_enabled(EFI_MEM_ATTR)) { efi_memattr_apply_permissions(NULL, efi_update_mem_attr); return; } /* * EFI_MEMORY_ATTRIBUTES_TABLE is intended to replace * EFI_PROPERTIES_TABLE. So, use EFI_PROPERTIES_TABLE to update * permissions only if EFI_MEMORY_ATTRIBUTES_TABLE is not * published by the firmware. Even if we find a buggy implementation of * EFI_MEMORY_ATTRIBUTES_TABLE, don't fall back to * EFI_PROPERTIES_TABLE, because of the same reason. */ if (!efi_enabled(EFI_NX_PE_DATA)) return; for_each_efi_memory_desc(md) { unsigned long pf = 0; if (!(md->attribute & EFI_MEMORY_RUNTIME)) continue; if (!(md->attribute & EFI_MEMORY_WB)) pf |= _PAGE_PCD; if ((md->attribute & EFI_MEMORY_XP) || (md->type == EFI_RUNTIME_SERVICES_DATA)) pf |= _PAGE_NX; if (!(md->attribute & EFI_MEMORY_RO) && (md->type != EFI_RUNTIME_SERVICES_CODE)) pf |= _PAGE_RW; if (sev_active()) pf |= _PAGE_ENC; efi_update_mappings(md, pf); } } void __init efi_dump_pagetable(void) { #ifdef CONFIG_EFI_PGT_DUMP if (efi_have_uv1_memmap()) ptdump_walk_pgd_level(NULL, &init_mm); else ptdump_walk_pgd_level(NULL, &efi_mm); #endif } /* * Makes the calling thread switch to/from efi_mm context. Can be used * in a kernel thread and user context. Preemption needs to remain disabled * while the EFI-mm is borrowed. mmgrab()/mmdrop() is not used because the mm * can not change under us. * It should be ensured that there are no concurent calls to this function. */ void efi_switch_mm(struct mm_struct *mm) { efi_scratch.prev_mm = current->active_mm; current->active_mm = mm; switch_mm(efi_scratch.prev_mm, mm, NULL); } static DEFINE_SPINLOCK(efi_runtime_lock); /* * DS and ES contain user values. We need to save them. * The 32-bit EFI code needs a valid DS, ES, and SS. There's no * need to save the old SS: __KERNEL_DS is always acceptable. */ #define __efi_thunk(func, ...) \ ({ \ efi_runtime_services_32_t *__rt; \ unsigned short __ds, __es; \ efi_status_t ____s; \ \ __rt = (void *)(unsigned long)efi.systab->mixed_mode.runtime; \ \ savesegment(ds, __ds); \ savesegment(es, __es); \ \ loadsegment(ss, __KERNEL_DS); \ loadsegment(ds, __KERNEL_DS); \ loadsegment(es, __KERNEL_DS); \ \ ____s = efi64_thunk(__rt->func, __VA_ARGS__); \ \ loadsegment(ds, __ds); \ loadsegment(es, __es); \ \ ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32; \ ____s; \ }) /* * Switch to the EFI page tables early so that we can access the 1:1 * runtime services mappings which are not mapped in any other page * tables. * * Also, disable interrupts because the IDT points to 64-bit handlers, * which aren't going to function correctly when we switch to 32-bit. */ #define efi_thunk(func...) \ ({ \ efi_status_t __s; \ \ arch_efi_call_virt_setup(); \ \ __s = __efi_thunk(func); \ \ arch_efi_call_virt_teardown(); \ \ __s; \ }) static efi_status_t __init __no_sanitize_address efi_thunk_set_virtual_address_map(unsigned long memory_map_size, unsigned long descriptor_size, u32 descriptor_version, efi_memory_desc_t *virtual_map) { efi_status_t status; unsigned long flags; efi_sync_low_kernel_mappings(); local_irq_save(flags); efi_switch_mm(&efi_mm); status = __efi_thunk(set_virtual_address_map, memory_map_size, descriptor_size, descriptor_version, virtual_map); efi_switch_mm(efi_scratch.prev_mm); local_irq_restore(flags); return status; } static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc) { return EFI_UNSUPPORTED; } static efi_status_t efi_thunk_set_time(efi_time_t *tm) { return EFI_UNSUPPORTED; } static efi_status_t efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending, efi_time_t *tm) { return EFI_UNSUPPORTED; } static efi_status_t efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) { return EFI_UNSUPPORTED; } static unsigned long efi_name_size(efi_char16_t *name) { return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1; } static efi_status_t efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor, u32 *attr, unsigned long *data_size, void *data) { u8 buf[24] __aligned(8); efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); efi_status_t status; u32 phys_name, phys_vendor, phys_attr; u32 phys_data_size, phys_data; unsigned long flags; spin_lock_irqsave(&efi_runtime_lock, flags); *vnd = *vendor; phys_data_size = virt_to_phys_or_null(data_size); phys_vendor = virt_to_phys_or_null(vnd); phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); phys_attr = virt_to_phys_or_null(attr); phys_data = virt_to_phys_or_null_size(data, *data_size); if (!phys_name || (data && !phys_data)) status = EFI_INVALID_PARAMETER; else status = efi_thunk(get_variable, phys_name, phys_vendor, phys_attr, phys_data_size, phys_data); spin_unlock_irqrestore(&efi_runtime_lock, flags); return status; } static efi_status_t efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor, u32 attr, unsigned long data_size, void *data) { u8 buf[24] __aligned(8); efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); u32 phys_name, phys_vendor, phys_data; efi_status_t status; unsigned long flags; spin_lock_irqsave(&efi_runtime_lock, flags); *vnd = *vendor; phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); phys_vendor = virt_to_phys_or_null(vnd); phys_data = virt_to_phys_or_null_size(data, data_size); if (!phys_name || !phys_data) status = EFI_INVALID_PARAMETER; else status = efi_thunk(set_variable, phys_name, phys_vendor, attr, data_size, phys_data); spin_unlock_irqrestore(&efi_runtime_lock, flags); return status; } static efi_status_t efi_thunk_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor, u32 attr, unsigned long data_size, void *data) { u8 buf[24] __aligned(8); efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); u32 phys_name, phys_vendor, phys_data; efi_status_t status; unsigned long flags; if (!spin_trylock_irqsave(&efi_runtime_lock, flags)) return EFI_NOT_READY; *vnd = *vendor; phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); phys_vendor = virt_to_phys_or_null(vnd); phys_data = virt_to_phys_or_null_size(data, data_size); if (!phys_name || !phys_data) status = EFI_INVALID_PARAMETER; else status = efi_thunk(set_variable, phys_name, phys_vendor, attr, data_size, phys_data); spin_unlock_irqrestore(&efi_runtime_lock, flags); return status; } static efi_status_t efi_thunk_get_next_variable(unsigned long *name_size, efi_char16_t *name, efi_guid_t *vendor) { u8 buf[24] __aligned(8); efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); efi_status_t status; u32 phys_name_size, phys_name, phys_vendor; unsigned long flags; spin_lock_irqsave(&efi_runtime_lock, flags); *vnd = *vendor; phys_name_size = virt_to_phys_or_null(name_size); phys_vendor = virt_to_phys_or_null(vnd); phys_name = virt_to_phys_or_null_size(name, *name_size); if (!phys_name) status = EFI_INVALID_PARAMETER; else status = efi_thunk(get_next_variable, phys_name_size, phys_name, phys_vendor); spin_unlock_irqrestore(&efi_runtime_lock, flags); *vendor = *vnd; return status; } static efi_status_t efi_thunk_get_next_high_mono_count(u32 *count) { return EFI_UNSUPPORTED; } static void efi_thunk_reset_system(int reset_type, efi_status_t status, unsigned long data_size, efi_char16_t *data) { u32 phys_data; unsigned long flags; spin_lock_irqsave(&efi_runtime_lock, flags); phys_data = virt_to_phys_or_null_size(data, data_size); efi_thunk(reset_system, reset_type, status, data_size, phys_data); spin_unlock_irqrestore(&efi_runtime_lock, flags); } static efi_status_t efi_thunk_update_capsule(efi_capsule_header_t **capsules, unsigned long count, unsigned long sg_list) { /* * To properly support this function we would need to repackage * 'capsules' because the firmware doesn't understand 64-bit * pointers. */ return EFI_UNSUPPORTED; } static efi_status_t efi_thunk_query_variable_info(u32 attr, u64 *storage_space, u64 *remaining_space, u64 *max_variable_size) { efi_status_t status; u32 phys_storage, phys_remaining, phys_max; unsigned long flags; if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) return EFI_UNSUPPORTED; spin_lock_irqsave(&efi_runtime_lock, flags); phys_storage = virt_to_phys_or_null(storage_space); phys_remaining = virt_to_phys_or_null(remaining_space); phys_max = virt_to_phys_or_null(max_variable_size); status = efi_thunk(query_variable_info, attr, phys_storage, phys_remaining, phys_max); spin_unlock_irqrestore(&efi_runtime_lock, flags); return status; } static efi_status_t efi_thunk_query_variable_info_nonblocking(u32 attr, u64 *storage_space, u64 *remaining_space, u64 *max_variable_size) { efi_status_t status; u32 phys_storage, phys_remaining, phys_max; unsigned long flags; if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) return EFI_UNSUPPORTED; if (!spin_trylock_irqsave(&efi_runtime_lock, flags)) return EFI_NOT_READY; phys_storage = virt_to_phys_or_null(storage_space); phys_remaining = virt_to_phys_or_null(remaining_space); phys_max = virt_to_phys_or_null(max_variable_size); status = efi_thunk(query_variable_info, attr, phys_storage, phys_remaining, phys_max); spin_unlock_irqrestore(&efi_runtime_lock, flags); return status; } static efi_status_t efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules, unsigned long count, u64 *max_size, int *reset_type) { /* * To properly support this function we would need to repackage * 'capsules' because the firmware doesn't understand 64-bit * pointers. */ return EFI_UNSUPPORTED; } void __init efi_thunk_runtime_setup(void) { if (!IS_ENABLED(CONFIG_EFI_MIXED)) return; efi.get_time = efi_thunk_get_time; efi.set_time = efi_thunk_set_time; efi.get_wakeup_time = efi_thunk_get_wakeup_time; efi.set_wakeup_time = efi_thunk_set_wakeup_time; efi.get_variable = efi_thunk_get_variable; efi.get_next_variable = efi_thunk_get_next_variable; efi.set_variable = efi_thunk_set_variable; efi.set_variable_nonblocking = efi_thunk_set_variable_nonblocking; efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count; efi.reset_system = efi_thunk_reset_system; efi.query_variable_info = efi_thunk_query_variable_info; efi.query_variable_info_nonblocking = efi_thunk_query_variable_info_nonblocking; efi.update_capsule = efi_thunk_update_capsule; efi.query_capsule_caps = efi_thunk_query_capsule_caps; } efi_status_t __init __no_sanitize_address efi_set_virtual_address_map(unsigned long memory_map_size, unsigned long descriptor_size, u32 descriptor_version, efi_memory_desc_t *virtual_map) { efi_status_t status; unsigned long flags; pgd_t *save_pgd = NULL; if (efi_is_mixed()) return efi_thunk_set_virtual_address_map(memory_map_size, descriptor_size, descriptor_version, virtual_map); if (efi_have_uv1_memmap()) { save_pgd = efi_uv1_memmap_phys_prolog(); if (!save_pgd) return EFI_ABORTED; } else { efi_switch_mm(&efi_mm); } kernel_fpu_begin(); /* Disable interrupts around EFI calls: */ local_irq_save(flags); status = efi_call(efi.systab->runtime->set_virtual_address_map, memory_map_size, descriptor_size, descriptor_version, virtual_map); local_irq_restore(flags); kernel_fpu_end(); if (save_pgd) efi_uv1_memmap_phys_epilog(save_pgd); else efi_switch_mm(efi_scratch.prev_mm); return status; }