1
2
3#include <linux/spinlock.h>
4#include <linux/percpu.h>
5#include <linux/kallsyms.h>
6#include <linux/kcore.h>
7
8#include <asm/cpu_entry_area.h>
9#include <asm/pgtable.h>
10#include <asm/fixmap.h>
11#include <asm/desc.h>
12
13static DEFINE_PER_CPU_PAGE_ALIGNED(struct entry_stack_page, entry_stack_storage);
14
15#ifdef CONFIG_X86_64
16static DEFINE_PER_CPU_PAGE_ALIGNED(struct exception_stacks, exception_stacks);
17DEFINE_PER_CPU(struct cea_exception_stacks*, cea_exception_stacks);
18#endif
19
20struct cpu_entry_area *get_cpu_entry_area(int cpu)
21{
22 unsigned long va = CPU_ENTRY_AREA_PER_CPU + cpu * CPU_ENTRY_AREA_SIZE;
23 BUILD_BUG_ON(sizeof(struct cpu_entry_area) % PAGE_SIZE != 0);
24
25 return (struct cpu_entry_area *) va;
26}
27EXPORT_SYMBOL(get_cpu_entry_area);
28
29void cea_set_pte(void *cea_vaddr, phys_addr_t pa, pgprot_t flags)
30{
31 unsigned long va = (unsigned long) cea_vaddr;
32 pte_t pte = pfn_pte(pa >> PAGE_SHIFT, flags);
33
34
35
36
37
38
39
40
41 if (boot_cpu_has(X86_FEATURE_PGE) &&
42 (pgprot_val(flags) & _PAGE_PRESENT))
43 pte = pte_set_flags(pte, _PAGE_GLOBAL);
44
45 set_pte_vaddr(va, pte);
46}
47
48static void __init
49cea_map_percpu_pages(void *cea_vaddr, void *ptr, int pages, pgprot_t prot)
50{
51 for ( ; pages; pages--, cea_vaddr+= PAGE_SIZE, ptr += PAGE_SIZE)
52 cea_set_pte(cea_vaddr, per_cpu_ptr_to_phys(ptr), prot);
53}
54
55static void __init percpu_setup_debug_store(unsigned int cpu)
56{
57#ifdef CONFIG_CPU_SUP_INTEL
58 unsigned int npages;
59 void *cea;
60
61 if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
62 return;
63
64 cea = &get_cpu_entry_area(cpu)->cpu_debug_store;
65 npages = sizeof(struct debug_store) / PAGE_SIZE;
66 BUILD_BUG_ON(sizeof(struct debug_store) % PAGE_SIZE != 0);
67 cea_map_percpu_pages(cea, &per_cpu(cpu_debug_store, cpu), npages,
68 PAGE_KERNEL);
69
70 cea = &get_cpu_entry_area(cpu)->cpu_debug_buffers;
71
72
73
74
75 npages = sizeof(struct debug_store_buffers) / PAGE_SIZE;
76 for (; npages; npages--, cea += PAGE_SIZE)
77 cea_set_pte(cea, 0, PAGE_NONE);
78#endif
79}
80
81#ifdef CONFIG_X86_64
82
83#define cea_map_stack(name) do { \
84 npages = sizeof(estacks->name## _stack) / PAGE_SIZE; \
85 cea_map_percpu_pages(cea->estacks.name## _stack, \
86 estacks->name## _stack, npages, PAGE_KERNEL); \
87 } while (0)
88
89static void __init percpu_setup_exception_stacks(unsigned int cpu)
90{
91 struct exception_stacks *estacks = per_cpu_ptr(&exception_stacks, cpu);
92 struct cpu_entry_area *cea = get_cpu_entry_area(cpu);
93 unsigned int npages;
94
95 BUILD_BUG_ON(sizeof(exception_stacks) % PAGE_SIZE != 0);
96
97 per_cpu(cea_exception_stacks, cpu) = &cea->estacks;
98
99
100
101
102
103
104 cea_map_stack(DF);
105 cea_map_stack(NMI);
106 cea_map_stack(DB1);
107 cea_map_stack(DB);
108 cea_map_stack(MCE);
109}
110#else
111static inline void percpu_setup_exception_stacks(unsigned int cpu) {}
112#endif
113
114
115static void __init setup_cpu_entry_area(unsigned int cpu)
116{
117 struct cpu_entry_area *cea = get_cpu_entry_area(cpu);
118#ifdef CONFIG_X86_64
119
120 pgprot_t gdt_prot = PAGE_KERNEL_RO;
121 pgprot_t tss_prot = PAGE_KERNEL_RO;
122#else
123
124
125
126
127
128
129
130
131
132
133 pgprot_t gdt_prot = boot_cpu_has(X86_FEATURE_XENPV) ?
134 PAGE_KERNEL_RO : PAGE_KERNEL;
135 pgprot_t tss_prot = PAGE_KERNEL;
136#endif
137
138 cea_set_pte(&cea->gdt, get_cpu_gdt_paddr(cpu), gdt_prot);
139
140 cea_map_percpu_pages(&cea->entry_stack_page,
141 per_cpu_ptr(&entry_stack_storage, cpu), 1,
142 PAGE_KERNEL);
143
144
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156
157
158
159
160
161 BUILD_BUG_ON((offsetof(struct tss_struct, x86_tss) ^
162 offsetofend(struct tss_struct, x86_tss)) & PAGE_MASK);
163 BUILD_BUG_ON(sizeof(struct tss_struct) % PAGE_SIZE != 0);
164 cea_map_percpu_pages(&cea->tss, &per_cpu(cpu_tss_rw, cpu),
165 sizeof(struct tss_struct) / PAGE_SIZE, tss_prot);
166
167#ifdef CONFIG_X86_32
168 per_cpu(cpu_entry_area, cpu) = cea;
169#endif
170
171 percpu_setup_exception_stacks(cpu);
172
173 percpu_setup_debug_store(cpu);
174}
175
176static __init void setup_cpu_entry_area_ptes(void)
177{
178#ifdef CONFIG_X86_32
179 unsigned long start, end;
180
181 BUILD_BUG_ON(CPU_ENTRY_AREA_PAGES * PAGE_SIZE < CPU_ENTRY_AREA_MAP_SIZE);
182 BUG_ON(CPU_ENTRY_AREA_BASE & ~PMD_MASK);
183
184 start = CPU_ENTRY_AREA_BASE;
185 end = start + CPU_ENTRY_AREA_MAP_SIZE;
186
187
188 for (; start < end && start >= CPU_ENTRY_AREA_BASE; start += PMD_SIZE)
189 populate_extra_pte(start);
190#endif
191}
192
193void __init setup_cpu_entry_areas(void)
194{
195 unsigned int cpu;
196
197 setup_cpu_entry_area_ptes();
198
199 for_each_possible_cpu(cpu)
200 setup_cpu_entry_area(cpu);
201
202
203
204
205
206 sync_initial_page_table();
207}
208