1 /* 2 * Hibernation support for x86-64 3 * 4 * Distribute under GPLv2 5 * 6 * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl> 7 * Copyright (c) 2002 Pavel Machek <pavel@ucw.cz> 8 * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org> 9 */ 10 11 #include <linux/gfp.h> 12 #include <linux/smp.h> 13 #include <linux/suspend.h> 14 #include <asm/proto.h> 15 #include <asm/page.h> 16 #include <asm/pgtable.h> 17 #include <asm/mtrr.h> 18 #include <asm/suspend.h> 19 20 /* References to section boundaries */ 21 extern const void __nosave_begin, __nosave_end; 22 23 /* Defined in hibernate_asm_64.S */ 24 extern int restore_image(void); 25 26 /* 27 * Address to jump to in the last phase of restore in order to get to the image 28 * kernel's text (this value is passed in the image header). 29 */ 30 unsigned long restore_jump_address; 31 32 /* 33 * Value of the cr3 register from before the hibernation (this value is passed 34 * in the image header). 35 */ 36 unsigned long restore_cr3; 37 38 pgd_t *temp_level4_pgt; 39 40 void *relocated_restore_code; 41 42 static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end) 43 { 44 long i, j; 45 46 i = pud_index(address); 47 pud = pud + i; 48 for (; i < PTRS_PER_PUD; pud++, i++) { 49 unsigned long paddr; 50 pmd_t *pmd; 51 52 paddr = address + i*PUD_SIZE; 53 if (paddr >= end) 54 break; 55 56 pmd = (pmd_t *)get_safe_page(GFP_ATOMIC); 57 if (!pmd) 58 return -ENOMEM; 59 set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE)); 60 for (j = 0; j < PTRS_PER_PMD; pmd++, j++, paddr += PMD_SIZE) { 61 unsigned long pe; 62 63 if (paddr >= end) 64 break; 65 pe = __PAGE_KERNEL_LARGE_EXEC | paddr; 66 pe &= __supported_pte_mask; 67 set_pmd(pmd, __pmd(pe)); 68 } 69 } 70 return 0; 71 } 72 73 static int set_up_temporary_mappings(void) 74 { 75 unsigned long start, end, next; 76 int error; 77 78 temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC); 79 if (!temp_level4_pgt) 80 return -ENOMEM; 81 82 /* It is safe to reuse the original kernel mapping */ 83 set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map), 84 init_level4_pgt[pgd_index(__START_KERNEL_map)]); 85 86 /* Set up the direct mapping from scratch */ 87 start = (unsigned long)pfn_to_kaddr(0); 88 end = (unsigned long)pfn_to_kaddr(max_pfn); 89 90 for (; start < end; start = next) { 91 pud_t *pud = (pud_t *)get_safe_page(GFP_ATOMIC); 92 if (!pud) 93 return -ENOMEM; 94 next = start + PGDIR_SIZE; 95 if (next > end) 96 next = end; 97 if ((error = res_phys_pud_init(pud, __pa(start), __pa(next)))) 98 return error; 99 set_pgd(temp_level4_pgt + pgd_index(start), 100 mk_kernel_pgd(__pa(pud))); 101 } 102 return 0; 103 } 104 105 int swsusp_arch_resume(void) 106 { 107 int error; 108 109 /* We have got enough memory and from now on we cannot recover */ 110 if ((error = set_up_temporary_mappings())) 111 return error; 112 113 relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC); 114 if (!relocated_restore_code) 115 return -ENOMEM; 116 memcpy(relocated_restore_code, &core_restore_code, 117 &restore_registers - &core_restore_code); 118 119 restore_image(); 120 return 0; 121 } 122 123 /* 124 * pfn_is_nosave - check if given pfn is in the 'nosave' section 125 */ 126 127 int pfn_is_nosave(unsigned long pfn) 128 { 129 unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT; 130 unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT; 131 return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); 132 } 133 134 struct restore_data_record { 135 unsigned long jump_address; 136 unsigned long cr3; 137 unsigned long magic; 138 }; 139 140 #define RESTORE_MAGIC 0x0123456789ABCDEFUL 141 142 /** 143 * arch_hibernation_header_save - populate the architecture specific part 144 * of a hibernation image header 145 * @addr: address to save the data at 146 */ 147 int arch_hibernation_header_save(void *addr, unsigned int max_size) 148 { 149 struct restore_data_record *rdr = addr; 150 151 if (max_size < sizeof(struct restore_data_record)) 152 return -EOVERFLOW; 153 rdr->jump_address = restore_jump_address; 154 rdr->cr3 = restore_cr3; 155 rdr->magic = RESTORE_MAGIC; 156 return 0; 157 } 158 159 /** 160 * arch_hibernation_header_restore - read the architecture specific data 161 * from the hibernation image header 162 * @addr: address to read the data from 163 */ 164 int arch_hibernation_header_restore(void *addr) 165 { 166 struct restore_data_record *rdr = addr; 167 168 restore_jump_address = rdr->jump_address; 169 restore_cr3 = rdr->cr3; 170 return (rdr->magic == RESTORE_MAGIC) ? 0 : -EINVAL; 171 } 172