summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/kexec.h
blob: 11b7c06e2828c30f1784a7727d0dc358d790877a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_KEXEC_H
#define _ASM_X86_KEXEC_H

#ifdef CONFIG_X86_32
# define PA_CONTROL_PAGE	0
# define VA_CONTROL_PAGE	1
# define PA_PGD			2
# define PA_SWAP_PAGE		3
# define PAGES_NR		4
#else
# define PA_CONTROL_PAGE	0
# define VA_CONTROL_PAGE	1
# define PA_TABLE_PAGE		2
# define PA_SWAP_PAGE		3
# define PAGES_NR		4
#endif

# define KEXEC_CONTROL_CODE_MAX_SIZE	2048

#ifndef __ASSEMBLY__

#include <linux/string.h>
#include <linux/kernel.h>

#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/bootparam.h>

struct kimage;

/*
 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
 * I.e. Maximum page that is mapped directly into kernel memory,
 * and kmap is not required.
 *
 * So far x86_64 is limited to 40 physical address bits.
 */
#ifdef CONFIG_X86_32
/* Maximum physical address we can use pages from */
# define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
/* Maximum address we can reach in physical address mode */
# define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
/* Maximum address we can use for the control code buffer */
# define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE

# define KEXEC_CONTROL_PAGE_SIZE	4096

/* The native architecture */
# define KEXEC_ARCH KEXEC_ARCH_386

/* We can also handle crash dumps from 64 bit kernel. */
# define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
#else
/* Maximum physical address we can use pages from */
# define KEXEC_SOURCE_MEMORY_LIMIT      (MAXMEM-1)
/* Maximum address we can reach in physical address mode */
# define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
/* Maximum address we can use for the control pages */
# define KEXEC_CONTROL_MEMORY_LIMIT     (MAXMEM-1)

/* Allocate one page for the pdp and the second for the code */
# define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)

/* The native architecture */
# define KEXEC_ARCH KEXEC_ARCH_X86_64
#endif

/*
 * This function is responsible for capturing register states if coming
 * via panic otherwise just fix up the ss and sp if coming via kernel
 * mode exception.
 */
static inline void crash_setup_regs(struct pt_regs *newregs,
				    struct pt_regs *oldregs)
{
	if (oldregs) {
		memcpy(newregs, oldregs, sizeof(*newregs));
	} else {
#ifdef CONFIG_X86_32
		asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
		asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
		asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
		asm volatile("movl %%esi,%0" : "=m"(newregs->si));
		asm volatile("movl %%edi,%0" : "=m"(newregs->di));
		asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
		asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
		asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
		asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
		asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
		asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
#else
		asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
		asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
		asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
		asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
		asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
		asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
		asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
		asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
		asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
		asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
		asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
		asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
		asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
		asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
		asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
		asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
		asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
#endif
		newregs->ip = _THIS_IP_;
	}
}

#ifdef CONFIG_X86_32
asmlinkage unsigned long
relocate_kernel(unsigned long indirection_page,
		unsigned long control_page,
		unsigned long start_address,
		unsigned int has_pae,
		unsigned int preserve_context);
#else
unsigned long
relocate_kernel(unsigned long indirection_page,
		unsigned long page_list,
		unsigned long start_address,
		unsigned int preserve_context,
		unsigned int host_mem_enc_active);
#endif

#define ARCH_HAS_KIMAGE_ARCH

#ifdef CONFIG_X86_32
struct kimage_arch {
	pgd_t *pgd;
#ifdef CONFIG_X86_PAE
	pmd_t *pmd0;
	pmd_t *pmd1;
#endif
	pte_t *pte0;
	pte_t *pte1;
};
#else
struct kimage_arch {
	p4d_t *p4d;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;
};
#endif /* CONFIG_X86_32 */

#ifdef CONFIG_X86_64
/*
 * Number of elements and order of elements in this structure should match
 * with the ones in arch/x86/purgatory/entry64.S. If you make a change here
 * make an appropriate change in purgatory too.
 */
struct kexec_entry64_regs {
	uint64_t rax;
	uint64_t rcx;
	uint64_t rdx;
	uint64_t rbx;
	uint64_t rsp;
	uint64_t rbp;
	uint64_t rsi;
	uint64_t rdi;
	uint64_t r8;
	uint64_t r9;
	uint64_t r10;
	uint64_t r11;
	uint64_t r12;
	uint64_t r13;
	uint64_t r14;
	uint64_t r15;
	uint64_t rip;
};

extern int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages,
				       gfp_t gfp);
#define arch_kexec_post_alloc_pages arch_kexec_post_alloc_pages

extern void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages);
#define arch_kexec_pre_free_pages arch_kexec_pre_free_pages

#endif

typedef void crash_vmclear_fn(void);
extern crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss;
extern void kdump_nmi_shootdown_cpus(void);

#endif /* __ASSEMBLY__ */

#endif /* _ASM_X86_KEXEC_H */