Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux-2.6.git] / arch / x86 / power / hibernate_64.c
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 }