xref: /linux/arch/x86/include/asm/kexec.h (revision 78c3925c048c752334873f56c3a3d1c9d53e0416)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_KEXEC_H
3 #define _ASM_X86_KEXEC_H
4 
5 #ifdef CONFIG_X86_32
6 # define PA_CONTROL_PAGE	0
7 # define VA_CONTROL_PAGE	1
8 # define PA_PGD			2
9 # define PA_SWAP_PAGE		3
10 # define PAGES_NR		4
11 #else
12 # define PA_CONTROL_PAGE	0
13 # define VA_CONTROL_PAGE	1
14 # define PA_TABLE_PAGE		2
15 # define PA_SWAP_PAGE		3
16 # define PAGES_NR		4
17 #endif
18 
19 # define KEXEC_CONTROL_CODE_MAX_SIZE	2048
20 
21 #ifndef __ASSEMBLY__
22 
23 #include <linux/string.h>
24 #include <linux/kernel.h>
25 
26 #include <asm/page.h>
27 #include <asm/ptrace.h>
28 
29 struct kimage;
30 
31 /*
32  * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
33  * I.e. Maximum page that is mapped directly into kernel memory,
34  * and kmap is not required.
35  *
36  * So far x86_64 is limited to 40 physical address bits.
37  */
38 #ifdef CONFIG_X86_32
39 /* Maximum physical address we can use pages from */
40 # define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
41 /* Maximum address we can reach in physical address mode */
42 # define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
43 /* Maximum address we can use for the control code buffer */
44 # define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
45 
46 # define KEXEC_CONTROL_PAGE_SIZE	4096
47 
48 /* The native architecture */
49 # define KEXEC_ARCH KEXEC_ARCH_386
50 
51 /* We can also handle crash dumps from 64 bit kernel. */
52 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
53 #else
54 /* Maximum physical address we can use pages from */
55 # define KEXEC_SOURCE_MEMORY_LIMIT      (MAXMEM-1)
56 /* Maximum address we can reach in physical address mode */
57 # define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
58 /* Maximum address we can use for the control pages */
59 # define KEXEC_CONTROL_MEMORY_LIMIT     (MAXMEM-1)
60 
61 /* Allocate one page for the pdp and the second for the code */
62 # define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)
63 
64 /* The native architecture */
65 # define KEXEC_ARCH KEXEC_ARCH_X86_64
66 #endif
67 
68 /*
69  * This function is responsible for capturing register states if coming
70  * via panic otherwise just fix up the ss and sp if coming via kernel
71  * mode exception.
72  */
73 static inline void crash_setup_regs(struct pt_regs *newregs,
74 				    struct pt_regs *oldregs)
75 {
76 	if (oldregs) {
77 		memcpy(newregs, oldregs, sizeof(*newregs));
78 	} else {
79 #ifdef CONFIG_X86_32
80 		asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
81 		asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
82 		asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
83 		asm volatile("movl %%esi,%0" : "=m"(newregs->si));
84 		asm volatile("movl %%edi,%0" : "=m"(newregs->di));
85 		asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
86 		asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
87 		asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
88 		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
89 		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
90 		asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
91 		asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
92 		asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
93 #else
94 		asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
95 		asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
96 		asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
97 		asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
98 		asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
99 		asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
100 		asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
101 		asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
102 		asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
103 		asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
104 		asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
105 		asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
106 		asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
107 		asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
108 		asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
109 		asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
110 		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
111 		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
112 		asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
113 #endif
114 		newregs->ip = _THIS_IP_;
115 	}
116 }
117 
118 #ifdef CONFIG_X86_32
119 asmlinkage unsigned long
120 relocate_kernel(unsigned long indirection_page,
121 		unsigned long control_page,
122 		unsigned long start_address,
123 		unsigned int has_pae,
124 		unsigned int preserve_context);
125 #else
126 unsigned long
127 relocate_kernel(unsigned long indirection_page,
128 		unsigned long page_list,
129 		unsigned long start_address,
130 		unsigned int preserve_context,
131 		unsigned int host_mem_enc_active);
132 #endif
133 
134 #define ARCH_HAS_KIMAGE_ARCH
135 
136 #ifdef CONFIG_X86_32
137 struct kimage_arch {
138 	pgd_t *pgd;
139 #ifdef CONFIG_X86_PAE
140 	pmd_t *pmd0;
141 	pmd_t *pmd1;
142 #endif
143 	pte_t *pte0;
144 	pte_t *pte1;
145 };
146 #else
147 struct kimage_arch {
148 	p4d_t *p4d;
149 	pud_t *pud;
150 	pmd_t *pmd;
151 	pte_t *pte;
152 };
153 #endif /* CONFIG_X86_32 */
154 
155 #ifdef CONFIG_X86_64
156 /*
157  * Number of elements and order of elements in this structure should match
158  * with the ones in arch/x86/purgatory/entry64.S. If you make a change here
159  * make an appropriate change in purgatory too.
160  */
161 struct kexec_entry64_regs {
162 	uint64_t rax;
163 	uint64_t rcx;
164 	uint64_t rdx;
165 	uint64_t rbx;
166 	uint64_t rsp;
167 	uint64_t rbp;
168 	uint64_t rsi;
169 	uint64_t rdi;
170 	uint64_t r8;
171 	uint64_t r9;
172 	uint64_t r10;
173 	uint64_t r11;
174 	uint64_t r12;
175 	uint64_t r13;
176 	uint64_t r14;
177 	uint64_t r15;
178 	uint64_t rip;
179 };
180 
181 extern int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages,
182 				       gfp_t gfp);
183 #define arch_kexec_post_alloc_pages arch_kexec_post_alloc_pages
184 
185 extern void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages);
186 #define arch_kexec_pre_free_pages arch_kexec_pre_free_pages
187 
188 void arch_kexec_protect_crashkres(void);
189 #define arch_kexec_protect_crashkres arch_kexec_protect_crashkres
190 
191 void arch_kexec_unprotect_crashkres(void);
192 #define arch_kexec_unprotect_crashkres arch_kexec_unprotect_crashkres
193 
194 #ifdef CONFIG_KEXEC_FILE
195 struct purgatory_info;
196 int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
197 				     Elf_Shdr *section,
198 				     const Elf_Shdr *relsec,
199 				     const Elf_Shdr *symtab);
200 #define arch_kexec_apply_relocations_add arch_kexec_apply_relocations_add
201 
202 int arch_kimage_file_post_load_cleanup(struct kimage *image);
203 #define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_cleanup
204 #endif
205 #endif
206 
207 extern void kdump_nmi_shootdown_cpus(void);
208 
209 #ifdef CONFIG_CRASH_HOTPLUG
210 void arch_crash_handle_hotplug_event(struct kimage *image);
211 #define arch_crash_handle_hotplug_event arch_crash_handle_hotplug_event
212 
213 #ifdef CONFIG_HOTPLUG_CPU
214 int arch_crash_hotplug_cpu_support(void);
215 #define crash_hotplug_cpu_support arch_crash_hotplug_cpu_support
216 #endif
217 
218 #ifdef CONFIG_MEMORY_HOTPLUG
219 int arch_crash_hotplug_memory_support(void);
220 #define crash_hotplug_memory_support arch_crash_hotplug_memory_support
221 #endif
222 
223 unsigned int arch_crash_get_elfcorehdr_size(void);
224 #define crash_get_elfcorehdr_size arch_crash_get_elfcorehdr_size
225 #endif
226 
227 #endif /* __ASSEMBLY__ */
228 
229 #endif /* _ASM_X86_KEXEC_H */
230