tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef _KEXEC_H
2#define _KEXEC_H
3
4#ifdef CONFIG_X86_32
5# define PA_CONTROL_PAGE 0
6# define VA_CONTROL_PAGE 1
7# define PA_PGD 2
8# define VA_PGD 3
9# define PA_PTE_0 4
10# define VA_PTE_0 5
11# define PA_PTE_1 6
12# define VA_PTE_1 7
13# ifdef CONFIG_X86_PAE
14# define PA_PMD_0 8
15# define VA_PMD_0 9
16# define PA_PMD_1 10
17# define VA_PMD_1 11
18# define PAGES_NR 12
19# else
20# define PAGES_NR 8
21# endif
22#else
23# define PA_CONTROL_PAGE 0
24# define VA_CONTROL_PAGE 1
25# define PA_PGD 2
26# define VA_PGD 3
27# define PA_PUD_0 4
28# define VA_PUD_0 5
29# define PA_PMD_0 6
30# define VA_PMD_0 7
31# define PA_PTE_0 8
32# define VA_PTE_0 9
33# define PA_PUD_1 10
34# define VA_PUD_1 11
35# define PA_PMD_1 12
36# define VA_PMD_1 13
37# define PA_PTE_1 14
38# define VA_PTE_1 15
39# define PA_TABLE_PAGE 16
40# define PAGES_NR 17
41#endif
42
43#ifndef __ASSEMBLY__
44
45#include <linux/string.h>
46
47#include <asm/page.h>
48#include <asm/ptrace.h>
49
50/*
51 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
52 * I.e. Maximum page that is mapped directly into kernel memory,
53 * and kmap is not required.
54 *
55 * So far x86_64 is limited to 40 physical address bits.
56 */
57#ifdef CONFIG_X86_32
58/* Maximum physical address we can use pages from */
59# define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
60/* Maximum address we can reach in physical address mode */
61# define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
62/* Maximum address we can use for the control code buffer */
63# define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
64
65# define KEXEC_CONTROL_CODE_SIZE 4096
66
67/* The native architecture */
68# define KEXEC_ARCH KEXEC_ARCH_386
69
70/* We can also handle crash dumps from 64 bit kernel. */
71# define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
72#else
73/* Maximum physical address we can use pages from */
74# define KEXEC_SOURCE_MEMORY_LIMIT (0xFFFFFFFFFFUL)
75/* Maximum address we can reach in physical address mode */
76# define KEXEC_DESTINATION_MEMORY_LIMIT (0xFFFFFFFFFFUL)
77/* Maximum address we can use for the control pages */
78# define KEXEC_CONTROL_MEMORY_LIMIT (0xFFFFFFFFFFUL)
79
80/* Allocate one page for the pdp and the second for the code */
81# define KEXEC_CONTROL_CODE_SIZE (4096UL + 4096UL)
82
83/* The native architecture */
84# define KEXEC_ARCH KEXEC_ARCH_X86_64
85#endif
86
87/*
88 * CPU does not save ss and sp on stack if execution is already
89 * running in kernel mode at the time of NMI occurrence. This code
90 * fixes it.
91 */
92static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
93 struct pt_regs *oldregs)
94{
95#ifdef CONFIG_X86_32
96 newregs->sp = (unsigned long)&(oldregs->sp);
97 asm volatile("xorl %%eax, %%eax\n\t"
98 "movw %%ss, %%ax\n\t"
99 :"=a"(newregs->ss));
100#endif
101}
102
103/*
104 * This function is responsible for capturing register states if coming
105 * via panic otherwise just fix up the ss and sp if coming via kernel
106 * mode exception.
107 */
108static inline void crash_setup_regs(struct pt_regs *newregs,
109 struct pt_regs *oldregs)
110{
111 if (oldregs) {
112 memcpy(newregs, oldregs, sizeof(*newregs));
113 crash_fixup_ss_esp(newregs, oldregs);
114 } else {
115#ifdef CONFIG_X86_32
116 asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
117 asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
118 asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
119 asm volatile("movl %%esi,%0" : "=m"(newregs->si));
120 asm volatile("movl %%edi,%0" : "=m"(newregs->di));
121 asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
122 asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
123 asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
124 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
125 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
126 asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
127 asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
128 asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
129#else
130 asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
131 asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
132 asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
133 asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
134 asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
135 asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
136 asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
137 asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
138 asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
139 asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
140 asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
141 asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
142 asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
143 asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
144 asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
145 asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
146 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
147 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
148 asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
149#endif
150 newregs->ip = (unsigned long)current_text_addr();
151 }
152}
153
154#ifdef CONFIG_X86_32
155asmlinkage NORET_TYPE void
156relocate_kernel(unsigned long indirection_page,
157 unsigned long control_page,
158 unsigned long start_address,
159 unsigned int has_pae) ATTRIB_NORET;
160#else
161NORET_TYPE void
162relocate_kernel(unsigned long indirection_page,
163 unsigned long page_list,
164 unsigned long start_address) ATTRIB_NORET;
165#endif
166
167#endif /* __ASSEMBLY__ */
168
169#endif /* _KEXEC_H */