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
res_phys_pud_init(pud_t * pud,unsigned long address,unsigned long end)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
set_up_temporary_mappings(void)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
swsusp_arch_resume(void)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
pfn_is_nosave(unsigned long pfn)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 */
arch_hibernation_header_save(void * addr,unsigned int max_size)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 */
arch_hibernation_header_restore(void * addr)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