^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Extensible Firmware Interface
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Based on Extensible Firmware Interface Specification version 2.4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Copyright (C) 2013, 2014 Linaro Ltd.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/efi.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <asm/efi.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * executable, everything else can be mapped with the XN bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * set. Also take the new (optional) RO/XP bits into account.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) static __init pteval_t create_mapping_protection(efi_memory_desc_t *md)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) u64 attr = md->attribute;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) u32 type = md->type;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) if (type == EFI_MEMORY_MAPPED_IO)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) return PROT_DEVICE_nGnRE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) if (WARN_ONCE(!PAGE_ALIGNED(md->phys_addr),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) "UEFI Runtime regions are not aligned to 64 KB -- buggy firmware?"))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * If the region is not aligned to the page size of the OS, we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * can not use strict permissions, since that would also affect
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * the mapping attributes of the adjacent regions.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) return pgprot_val(PAGE_KERNEL_EXEC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) /* R-- */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) if ((attr & (EFI_MEMORY_XP | EFI_MEMORY_RO)) ==
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) (EFI_MEMORY_XP | EFI_MEMORY_RO))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) return pgprot_val(PAGE_KERNEL_RO);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) /* R-X */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) if (attr & EFI_MEMORY_RO)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) return pgprot_val(PAGE_KERNEL_ROX);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) /* RW- */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) if (((attr & (EFI_MEMORY_RP | EFI_MEMORY_WP | EFI_MEMORY_XP)) ==
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) EFI_MEMORY_XP) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) type != EFI_RUNTIME_SERVICES_CODE)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) return pgprot_val(PAGE_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) /* RWX */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) return pgprot_val(PAGE_KERNEL_EXEC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) /* we will fill this structure from the stub, so don't put it in .bss */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) struct screen_info screen_info __section(".data");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) pteval_t prot_val = create_mapping_protection(md);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) bool page_mappings_only = (md->type == EFI_RUNTIME_SERVICES_CODE ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) md->type == EFI_RUNTIME_SERVICES_DATA);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) if (!PAGE_ALIGNED(md->phys_addr) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) !PAGE_ALIGNED(md->num_pages << EFI_PAGE_SHIFT)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) * If the end address of this region is not aligned to page
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) * size, the mapping is rounded up, and may end up sharing a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) * page frame with the next UEFI memory region. If we create
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) * a block entry now, we may need to split it again when mapping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) * the next region, and support for that is going to be removed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) * from the MMU routines. So avoid block mappings altogether in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) * that case.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) page_mappings_only = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) create_pgd_mapping(mm, md->phys_addr, md->virt_addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) md->num_pages << EFI_PAGE_SHIFT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) __pgprot(prot_val | PTE_NG), page_mappings_only);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) static int __init set_permissions(pte_t *ptep, unsigned long addr, void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) efi_memory_desc_t *md = data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) pte_t pte = READ_ONCE(*ptep);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) if (md->attribute & EFI_MEMORY_RO)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) pte = set_pte_bit(pte, __pgprot(PTE_RDONLY));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) if (md->attribute & EFI_MEMORY_XP)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) pte = set_pte_bit(pte, __pgprot(PTE_PXN));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) set_pte(ptep, pte);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) int __init efi_set_mapping_permissions(struct mm_struct *mm,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) efi_memory_desc_t *md)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) BUG_ON(md->type != EFI_RUNTIME_SERVICES_CODE &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) md->type != EFI_RUNTIME_SERVICES_DATA);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) * Calling apply_to_page_range() is only safe on regions that are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) * guaranteed to be mapped down to pages. Since we are only called
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) * for regions that have been mapped using efi_create_mapping() above
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) * (and this is checked by the generic Memory Attributes table parsing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) * routines), there is no need to check that again here.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) return apply_to_page_range(mm, md->virt_addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) md->num_pages << EFI_PAGE_SHIFT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) set_permissions, md);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) * UpdateCapsule() depends on the system being shutdown via
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) * ResetSystem().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) bool efi_poweroff_required(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) return efi_enabled(EFI_RUNTIME_SERVICES);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) asmlinkage efi_status_t efi_handle_corrupted_x18(efi_status_t s, const char *f)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) pr_err_ratelimited(FW_BUG "register x18 corrupted by EFI %s\n", f);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) return s;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags