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 15 #include <asm/init.h> 16 #include <asm/proto.h> 17 #include <asm/page.h> 18 #include <asm/pgtable.h> 19 #include <asm/mtrr.h> 20 #include <asm/sections.h> 21 #include <asm/suspend.h> 22 23 /* Defined in hibernate_asm_64.S */ 24 extern asmlinkage __visible 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 __visible; 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 __visible; 37 38 pgd_t *temp_level4_pgt __visible; 39 40 void *relocated_restore_code __visible; 41 42 static void *alloc_pgt_page(void *context) 43 { 44 return (void *)get_safe_page(GFP_ATOMIC); 45 } 46 47 static int set_up_temporary_mappings(void) 48 { 49 struct x86_mapping_info info = { 50 .alloc_pgt_page = alloc_pgt_page, 51 .pmd_flag = __PAGE_KERNEL_LARGE_EXEC, 52 .kernel_mapping = true, 53 }; 54 unsigned long mstart, mend; 55 int result; 56 int i; 57 58 temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC); 59 if (!temp_level4_pgt) 60 return -ENOMEM; 61 62 /* It is safe to reuse the original kernel mapping */ 63 set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map), 64 init_level4_pgt[pgd_index(__START_KERNEL_map)]); 65 66 /* Set up the direct mapping from scratch */ 67 for (i = 0; i < nr_pfn_mapped; i++) { 68 mstart = pfn_mapped[i].start << PAGE_SHIFT; 69 mend = pfn_mapped[i].end << PAGE_SHIFT; 70 71 result = kernel_ident_mapping_init(&info, temp_level4_pgt, 72 mstart, mend); 73 74 if (result) 75 return result; 76 } 77 78 return 0; 79 } 80 81 int swsusp_arch_resume(void) 82 { 83 int error; 84 85 /* We have got enough memory and from now on we cannot recover */ 86 if ((error = set_up_temporary_mappings())) 87 return error; 88 89 relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC); 90 if (!relocated_restore_code) 91 return -ENOMEM; 92 memcpy(relocated_restore_code, &core_restore_code, 93 &restore_registers - &core_restore_code); 94 95 restore_image(); 96 return 0; 97 } 98 99 /* 100 * pfn_is_nosave - check if given pfn is in the 'nosave' section 101 */ 102 103 int pfn_is_nosave(unsigned long pfn) 104 { 105 unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT; 106 unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT; 107 return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); 108 } 109 110 struct restore_data_record { 111 unsigned long jump_address; 112 unsigned long cr3; 113 unsigned long magic; 114 }; 115 116 #define RESTORE_MAGIC 0x0123456789ABCDEFUL 117 118 /** 119 * arch_hibernation_header_save - populate the architecture specific part 120 * of a hibernation image header 121 * @addr: address to save the data at 122 */ 123 int arch_hibernation_header_save(void *addr, unsigned int max_size) 124 { 125 struct restore_data_record *rdr = addr; 126 127 if (max_size < sizeof(struct restore_data_record)) 128 return -EOVERFLOW; 129 rdr->jump_address = restore_jump_address; 130 rdr->cr3 = restore_cr3; 131 rdr->magic = RESTORE_MAGIC; 132 return 0; 133 } 134 135 /** 136 * arch_hibernation_header_restore - read the architecture specific data 137 * from the hibernation image header 138 * @addr: address to read the data from 139 */ 140 int arch_hibernation_header_restore(void *addr) 141 { 142 struct restore_data_record *rdr = addr; 143 144 restore_jump_address = rdr->jump_address; 145 restore_cr3 = rdr->cr3; 146 return (rdr->magic == RESTORE_MAGIC) ? 0 : -EINVAL; 147 } 148