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