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 #endif
12
13 # define KEXEC_CONTROL_PAGE_SIZE 4096
14 # define KEXEC_CONTROL_CODE_MAX_SIZE 2048
15
16 #ifndef __ASSEMBLY__
17
18 #include <linux/string.h>
19 #include <linux/kernel.h>
20
21 #include <asm/page.h>
22 #include <asm/ptrace.h>
23
24 struct kimage;
25
26 /*
27 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
28 * I.e. Maximum page that is mapped directly into kernel memory,
29 * and kmap is not required.
30 *
31 * So far x86_64 is limited to 40 physical address bits.
32 */
33 #ifdef CONFIG_X86_32
34 /* Maximum physical address we can use pages from */
35 # define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
36 /* Maximum address we can reach in physical address mode */
37 # define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
38 /* Maximum address we can use for the control code buffer */
39 # define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
40
41
42 /* The native architecture */
43 # define KEXEC_ARCH KEXEC_ARCH_386
44
45 /* We can also handle crash dumps from 64 bit kernel. */
46 # define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
47 #else
48 /* Maximum physical address we can use pages from */
49 # define KEXEC_SOURCE_MEMORY_LIMIT (MAXMEM-1)
50 /* Maximum address we can reach in physical address mode */
51 # define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
52 /* Maximum address we can use for the control pages */
53 # define KEXEC_CONTROL_MEMORY_LIMIT (MAXMEM-1)
54
55 /* The native architecture */
56 # define KEXEC_ARCH KEXEC_ARCH_X86_64
57
58 extern unsigned long kexec_va_control_page;
59 extern unsigned long kexec_pa_table_page;
60 extern unsigned long kexec_pa_swap_page;
61 #endif
62
63 /*
64 * This function is responsible for capturing register states if coming
65 * via panic otherwise just fix up the ss and sp if coming via kernel
66 * mode exception.
67 */
crash_setup_regs(struct pt_regs * newregs,struct pt_regs * oldregs)68 static inline void crash_setup_regs(struct pt_regs *newregs,
69 struct pt_regs *oldregs)
70 {
71 if (oldregs) {
72 memcpy(newregs, oldregs, sizeof(*newregs));
73 } else {
74 #ifdef CONFIG_X86_32
75 asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
76 asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
77 asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
78 asm volatile("movl %%esi,%0" : "=m"(newregs->si));
79 asm volatile("movl %%edi,%0" : "=m"(newregs->di));
80 asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
81 asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
82 asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
83 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
84 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
85 asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
86 asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
87 asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
88 #else
89 asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
90 asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
91 asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
92 asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
93 asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
94 asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
95 asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
96 asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
97 asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
98 asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
99 asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
100 asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
101 asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
102 asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
103 asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
104 asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
105 asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
106 asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
107 asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
108 #endif
109 newregs->ip = _THIS_IP_;
110 }
111 }
112
113 #ifdef CONFIG_X86_32
114 typedef asmlinkage unsigned long
115 relocate_kernel_fn(unsigned long indirection_page,
116 unsigned long control_page,
117 unsigned long start_address,
118 unsigned int has_pae,
119 unsigned int preserve_context);
120 #else
121 typedef unsigned long
122 relocate_kernel_fn(unsigned long indirection_page,
123 unsigned long pa_control_page,
124 unsigned long start_address,
125 unsigned int preserve_context,
126 unsigned int host_mem_enc_active);
127 #endif
128 extern relocate_kernel_fn relocate_kernel;
129 #define ARCH_HAS_KIMAGE_ARCH
130
131 #ifdef CONFIG_X86_32
132 struct kimage_arch {
133 pgd_t *pgd;
134 #ifdef CONFIG_X86_PAE
135 pmd_t *pmd0;
136 pmd_t *pmd1;
137 #endif
138 pte_t *pte0;
139 pte_t *pte1;
140 };
141 #else
142 struct kimage_arch {
143 /*
144 * This is a kimage control page, as it must not overlap with either
145 * source or destination address ranges.
146 */
147 pgd_t *pgd;
148 /*
149 * The virtual mapping of the control code page itself is used only
150 * during the transition, while the current kernel's pages are all
151 * in place. Thus the intermediate page table pages used to map it
152 * are not control pages, but instead just normal pages obtained
153 * with get_zeroed_page(). And have to be tracked (below) so that
154 * they can be freed.
155 */
156 p4d_t *p4d;
157 pud_t *pud;
158 pmd_t *pmd;
159 pte_t *pte;
160 };
161 #endif /* CONFIG_X86_32 */
162
163 #ifdef CONFIG_X86_64
164 /*
165 * Number of elements and order of elements in this structure should match
166 * with the ones in arch/x86/purgatory/entry64.S. If you make a change here
167 * make an appropriate change in purgatory too.
168 */
169 struct kexec_entry64_regs {
170 uint64_t rax;
171 uint64_t rcx;
172 uint64_t rdx;
173 uint64_t rbx;
174 uint64_t rsp;
175 uint64_t rbp;
176 uint64_t rsi;
177 uint64_t rdi;
178 uint64_t r8;
179 uint64_t r9;
180 uint64_t r10;
181 uint64_t r11;
182 uint64_t r12;
183 uint64_t r13;
184 uint64_t r14;
185 uint64_t r15;
186 uint64_t rip;
187 };
188
189 extern int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages,
190 gfp_t gfp);
191 #define arch_kexec_post_alloc_pages arch_kexec_post_alloc_pages
192
193 extern void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages);
194 #define arch_kexec_pre_free_pages arch_kexec_pre_free_pages
195
196 void arch_kexec_protect_crashkres(void);
197 #define arch_kexec_protect_crashkres arch_kexec_protect_crashkres
198
199 void arch_kexec_unprotect_crashkres(void);
200 #define arch_kexec_unprotect_crashkres arch_kexec_unprotect_crashkres
201
202 #ifdef CONFIG_KEXEC_FILE
203 struct purgatory_info;
204 int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
205 Elf_Shdr *section,
206 const Elf_Shdr *relsec,
207 const Elf_Shdr *symtab);
208 #define arch_kexec_apply_relocations_add arch_kexec_apply_relocations_add
209
210 int arch_kimage_file_post_load_cleanup(struct kimage *image);
211 #define arch_kimage_file_post_load_cleanup arch_kimage_file_post_load_cleanup
212 #endif
213 #endif
214
215 extern void kdump_nmi_shootdown_cpus(void);
216
217 #ifdef CONFIG_CRASH_HOTPLUG
218 void arch_crash_handle_hotplug_event(struct kimage *image, void *arg);
219 #define arch_crash_handle_hotplug_event arch_crash_handle_hotplug_event
220
221 int arch_crash_hotplug_support(struct kimage *image, unsigned long kexec_flags);
222 #define arch_crash_hotplug_support arch_crash_hotplug_support
223
224 unsigned int arch_crash_get_elfcorehdr_size(void);
225 #define crash_get_elfcorehdr_size arch_crash_get_elfcorehdr_size
226 #endif
227
228 #endif /* __ASSEMBLY__ */
229
230 #endif /* _ASM_X86_KEXEC_H */
231