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