| | 1 | // SPDX-License-Identifier: GPL-2.0-only |
| | 2 | /* |
| | 3 | * Hibernation support for x86-64 |
| | 4 | * |
| | 5 | * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl> |
| | 6 | * Copyright (c) 2002 Pavel Machek <pavel@ucw.cz> |
| | 7 | * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org> |
| | 8 | */ |
| | 9 | |
| | 10 | #include <linux/gfp.h> |
| | 11 | #include <linux/smp.h> |
| | 12 | #include <linux/suspend.h> |
| | 13 | #include <linux/scatterlist.h> |
| | 14 | #include <linux/kdebug.h> |
| | 15 | #include <linux/pgtable.h> |
| | 16 | |
| | 17 | #include <crypto/hash.h> |
| | 18 | |
| | 19 | #include <asm/e820/api.h> |
| | 20 | #include <asm/init.h> |
| | 21 | #include <asm/proto.h> |
| | 22 | #include <asm/page.h> |
| | 23 | #include <asm/mtrr.h> |
| | 24 | #include <asm/sections.h> |
| | 25 | #include <asm/suspend.h> |
| | 26 | #include <asm/tlbflush.h> |
| | 27 | |
| | 28 | static int set_up_temporary_text_mapping(pgd_t *pgd) |
| | 29 | { |
| | 30 | pmd_t *pmd; |
| | 31 | pud_t *pud; |
| | 32 | p4d_t *p4d = NULL; |
| | 33 | pgprot_t pgtable_prot = __pgprot(_KERNPG_TABLE); |
| | 34 | pgprot_t pmd_text_prot = __pgprot(__PAGE_KERNEL_LARGE_EXEC); |
| | 35 | |
| | 36 | /* Filter out unsupported __PAGE_KERNEL* bits: */ |
| | 37 | pgprot_val(pmd_text_prot) &= __default_kernel_pte_mask; |
| | 38 | pgprot_val(pgtable_prot) &= __default_kernel_pte_mask; |
| | 39 | |
| | 40 | /* |
| | 41 | * The new mapping only has to cover the page containing the image |
| | 42 | * kernel's entry point (jump_address_phys), because the switch over to |
| | 43 | * it is carried out by relocated code running from a page allocated |
| | 44 | * specifically for this purpose and covered by the identity mapping, so |
| | 45 | * the temporary kernel text mapping is only needed for the final jump. |
| | 46 | * Moreover, in that mapping the virtual address of the image kernel's |
| | 47 | * entry point must be the same as its virtual address in the image |
| | 48 | * kernel (restore_jump_address), so the image kernel's |
| | 49 | * restore_registers() code doesn't find itself in a different area of |
| | 50 | * the virtual address space after switching over to the original page |
| | 51 | * tables used by the image kernel. |
| | 52 | */ |
| | 53 | |
| | 54 | if (pgtable_l5_enabled()) { |
| | 55 | p4d = (p4d_t *)get_safe_page(GFP_ATOMIC); |
| | 56 | if (!p4d) |
| | 57 | return -ENOMEM; |
| | 58 | } |
| | 59 | |
| | 60 | pud = (pud_t *)get_safe_page(GFP_ATOMIC); |
| | 61 | if (!pud) |
| | 62 | return -ENOMEM; |
| | 63 | |
| | 64 | pmd = (pmd_t *)get_safe_page(GFP_ATOMIC); |
| | 65 | if (!pmd) |
| | 66 | return -ENOMEM; |
| | 67 | |
| | 68 | set_pmd(pmd + pmd_index(restore_jump_address), |
| | 69 | __pmd((jump_address_phys & PMD_MASK) | pgprot_val(pmd_text_prot))); |
| | 70 | set_pud(pud + pud_index(restore_jump_address), |
| | 71 | __pud(__pa(pmd) | pgprot_val(pgtable_prot))); |
| | 72 | if (p4d) { |
| | 73 | p4d_t new_p4d = __p4d(__pa(pud) | pgprot_val(pgtable_prot)); |
| | 74 | pgd_t new_pgd = __pgd(__pa(p4d) | pgprot_val(pgtable_prot)); |
| | 75 | |
| | 76 | set_p4d(p4d + p4d_index(restore_jump_address), new_p4d); |
| | 77 | set_pgd(pgd + pgd_index(restore_jump_address), new_pgd); |
| | 78 | } else { |
| | 79 | /* No p4d for 4-level paging: point the pgd to the pud page table */ |
| | 80 | pgd_t new_pgd = __pgd(__pa(pud) | pgprot_val(pgtable_prot)); |
| | 81 | set_pgd(pgd + pgd_index(restore_jump_address), new_pgd); |
| | 82 | } |
| | 83 | |
| | 84 | return 0; |
| | 85 | } |
| | 86 | |
| | 87 | static void *alloc_pgt_page(void *context) |
| | 88 | { |
| | 89 | return (void *)get_safe_page(GFP_ATOMIC); |
| | 90 | } |
| | 91 | |
| | 92 | static int set_up_temporary_mappings(void) |
| | 93 | { |
| | 94 | struct x86_mapping_info info = { |
| | 95 | .alloc_pgt_page = alloc_pgt_page, |
| | 96 | .page_flag = __PAGE_KERNEL_LARGE_EXEC, |
| | 97 | .offset = __PAGE_OFFSET, |
| | 98 | }; |
| | 99 | unsigned long mstart, mend; |
| | 100 | pgd_t *pgd; |
| | 101 | int result; |
| | 102 | int i; |
| | 103 | |
| | 104 | pgd = (pgd_t *)get_safe_page(GFP_ATOMIC); |
| | 105 | if (!pgd) |
| | 106 | return -ENOMEM; |
| | 107 | |
| | 108 | /* Prepare a temporary mapping for the kernel text */ |
| | 109 | result = set_up_temporary_text_mapping(pgd); |
| | 110 | if (result) |
| | 111 | return result; |
| | 112 | |
| | 113 | /* Set up the direct mapping from scratch */ |
| | 114 | for (i = 0; i < nr_pfn_mapped; i++) { |
| | 115 | mstart = pfn_mapped[i].start << PAGE_SHIFT; |
| | 116 | mend = pfn_mapped[i].end << PAGE_SHIFT; |
| | 117 | |
| | 118 | result = kernel_ident_mapping_init(&info, pgd, mstart, mend); |
| | 119 | if (result) |
| | 120 | return result; |
| | 121 | } |
| | 122 | |
| | 123 | temp_pgt = __pa(pgd); |
| | 124 | return 0; |
| | 125 | } |
| | 126 | |
| | 127 | asmlinkage int swsusp_arch_resume(void) |
| | 128 | { |
| | 129 | int error; |
| | 130 | |
| | 131 | /* We have got enough memory and from now on we cannot recover */ |
| | 132 | error = set_up_temporary_mappings(); |
| | 133 | if (error) |
| | 134 | return error; |
| | 135 | |
| | 136 | error = relocate_restore_code(); |
| | 137 | if (error) |
| | 138 | return error; |
| | 139 | |
| | 140 | restore_image(); |
| | 141 | return 0; |
| | 142 | } |
projects / linux-2.6-block.git / blame_incremental