Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 | // SPDX-License-Identifier: GPL-2.0-only /* * Hibernation support for x86-64 * * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl> * Copyright (c) 2002 Pavel Machek <pavel@ucw.cz> * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org> */ #include <linux/gfp.h> #include <linux/smp.h> #include <linux/suspend.h> #include <linux/scatterlist.h> #include <linux/kdebug.h> #include <linux/pgtable.h> #include <crypto/hash.h> #include <asm/e820/api.h> #include <asm/init.h> #include <asm/proto.h> #include <asm/page.h> #include <asm/mtrr.h> #include <asm/sections.h> #include <asm/suspend.h> #include <asm/tlbflush.h> static int set_up_temporary_text_mapping(pgd_t *pgd) { pmd_t *pmd; pud_t *pud; p4d_t *p4d = NULL; pgprot_t pgtable_prot = __pgprot(_KERNPG_TABLE); pgprot_t pmd_text_prot = __pgprot(__PAGE_KERNEL_LARGE_EXEC); /* Filter out unsupported __PAGE_KERNEL* bits: */ pgprot_val(pmd_text_prot) &= __default_kernel_pte_mask; pgprot_val(pgtable_prot) &= __default_kernel_pte_mask; /* * The new mapping only has to cover the page containing the image * kernel's entry point (jump_address_phys), because the switch over to * it is carried out by relocated code running from a page allocated * specifically for this purpose and covered by the identity mapping, so * the temporary kernel text mapping is only needed for the final jump. * Moreover, in that mapping the virtual address of the image kernel's * entry point must be the same as its virtual address in the image * kernel (restore_jump_address), so the image kernel's * restore_registers() code doesn't find itself in a different area of * the virtual address space after switching over to the original page * tables used by the image kernel. */ if (pgtable_l5_enabled()) { p4d = (p4d_t *)get_safe_page(GFP_ATOMIC); if (!p4d) return -ENOMEM; } pud = (pud_t *)get_safe_page(GFP_ATOMIC); if (!pud) return -ENOMEM; pmd = (pmd_t *)get_safe_page(GFP_ATOMIC); if (!pmd) return -ENOMEM; set_pmd(pmd + pmd_index(restore_jump_address), __pmd((jump_address_phys & PMD_MASK) | pgprot_val(pmd_text_prot))); set_pud(pud + pud_index(restore_jump_address), __pud(__pa(pmd) | pgprot_val(pgtable_prot))); if (p4d) { p4d_t new_p4d = __p4d(__pa(pud) | pgprot_val(pgtable_prot)); pgd_t new_pgd = __pgd(__pa(p4d) | pgprot_val(pgtable_prot)); set_p4d(p4d + p4d_index(restore_jump_address), new_p4d); set_pgd(pgd + pgd_index(restore_jump_address), new_pgd); } else { /* No p4d for 4-level paging: point the pgd to the pud page table */ pgd_t new_pgd = __pgd(__pa(pud) | pgprot_val(pgtable_prot)); set_pgd(pgd + pgd_index(restore_jump_address), new_pgd); } return 0; } static void *alloc_pgt_page(void *context) { return (void *)get_safe_page(GFP_ATOMIC); } static int set_up_temporary_mappings(void) { struct x86_mapping_info info = { .alloc_pgt_page = alloc_pgt_page, .page_flag = __PAGE_KERNEL_LARGE_EXEC, .offset = __PAGE_OFFSET, }; unsigned long mstart, mend; pgd_t *pgd; int result; int i; pgd = (pgd_t *)get_safe_page(GFP_ATOMIC); if (!pgd) return -ENOMEM; /* Prepare a temporary mapping for the kernel text */ result = set_up_temporary_text_mapping(pgd); if (result) return result; /* Set up the direct mapping from scratch */ for (i = 0; i < nr_pfn_mapped; i++) { mstart = pfn_mapped[i].start << PAGE_SHIFT; mend = pfn_mapped[i].end << PAGE_SHIFT; result = kernel_ident_mapping_init(&info, pgd, mstart, mend); if (result) return result; } temp_pgt = __pa(pgd); return 0; } asmlinkage int swsusp_arch_resume(void) { int error; /* We have got enough memory and from now on we cannot recover */ error = set_up_temporary_mappings(); if (error) return error; error = relocate_restore_code(); if (error) return error; restore_image(); return 0; } |