1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef LINUX_KEXEC_H
3 #define LINUX_KEXEC_H
4
5 #define IND_DESTINATION_BIT 0
6 #define IND_INDIRECTION_BIT 1
7 #define IND_DONE_BIT 2
8 #define IND_SOURCE_BIT 3
9
10 #define IND_DESTINATION (1 << IND_DESTINATION_BIT)
11 #define IND_INDIRECTION (1 << IND_INDIRECTION_BIT)
12 #define IND_DONE (1 << IND_DONE_BIT)
13 #define IND_SOURCE (1 << IND_SOURCE_BIT)
14 #define IND_FLAGS (IND_DESTINATION | IND_INDIRECTION | IND_DONE | IND_SOURCE)
15
16 #if !defined(__ASSEMBLY__)
17
18 #include <linux/crash_core.h>
19 #include <asm/io.h>
20
21 #include <uapi/linux/kexec.h>
22
23 #ifdef CONFIG_KEXEC_CORE
24 #include <linux/list.h>
25 #include <linux/compat.h>
26 #include <linux/ioport.h>
27 #include <linux/module.h>
28 #include <asm/kexec.h>
29
30 /* Verify architecture specific macros are defined */
31
32 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
33 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
34 #endif
35
36 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
37 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
38 #endif
39
40 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
41 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
42 #endif
43
44 #ifndef KEXEC_CONTROL_MEMORY_GFP
45 #define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
46 #endif
47
48 #ifndef KEXEC_CONTROL_PAGE_SIZE
49 #error KEXEC_CONTROL_PAGE_SIZE not defined
50 #endif
51
52 #ifndef KEXEC_ARCH
53 #error KEXEC_ARCH not defined
54 #endif
55
56 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
57 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
58 #endif
59
60 #ifndef KEXEC_CRASH_MEM_ALIGN
61 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
62 #endif
63
64 #define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME
65
66 /*
67 * This structure is used to hold the arguments that are used when loading
68 * kernel binaries.
69 */
70
71 typedef unsigned long kimage_entry_t;
72
73 struct kexec_segment {
74 /*
75 * This pointer can point to user memory if kexec_load() system
76 * call is used or will point to kernel memory if
77 * kexec_file_load() system call is used.
78 *
79 * Use ->buf when expecting to deal with user memory and use ->kbuf
80 * when expecting to deal with kernel memory.
81 */
82 union {
83 void __user *buf;
84 void *kbuf;
85 };
86 size_t bufsz;
87 unsigned long mem;
88 size_t memsz;
89 };
90
91 #ifdef CONFIG_COMPAT
92 struct compat_kexec_segment {
93 compat_uptr_t buf;
94 compat_size_t bufsz;
95 compat_ulong_t mem; /* User space sees this as a (void *) ... */
96 compat_size_t memsz;
97 };
98 #endif
99
100 #ifdef CONFIG_KEXEC_FILE
101 struct purgatory_info {
102 /*
103 * Pointer to elf header at the beginning of kexec_purgatory.
104 * Note: kexec_purgatory is read only
105 */
106 const Elf_Ehdr *ehdr;
107 /*
108 * Temporary, modifiable buffer for sechdrs used for relocation.
109 * This memory can be freed post image load.
110 */
111 Elf_Shdr *sechdrs;
112 /*
113 * Temporary, modifiable buffer for stripped purgatory used for
114 * relocation. This memory can be freed post image load.
115 */
116 void *purgatory_buf;
117 };
118
119 struct kimage;
120
121 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
122 typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
123 unsigned long kernel_len, char *initrd,
124 unsigned long initrd_len, char *cmdline,
125 unsigned long cmdline_len);
126 typedef int (kexec_cleanup_t)(void *loader_data);
127
128 #ifdef CONFIG_KEXEC_VERIFY_SIG
129 typedef int (kexec_verify_sig_t)(const char *kernel_buf,
130 unsigned long kernel_len);
131 #endif
132
133 struct kexec_file_ops {
134 kexec_probe_t *probe;
135 kexec_load_t *load;
136 kexec_cleanup_t *cleanup;
137 #ifdef CONFIG_KEXEC_VERIFY_SIG
138 kexec_verify_sig_t *verify_sig;
139 #endif
140 };
141
142 extern const struct kexec_file_ops * const kexec_file_loaders[];
143
144 int kexec_image_probe_default(struct kimage *image, void *buf,
145 unsigned long buf_len);
146
147 /**
148 * struct kexec_buf - parameters for finding a place for a buffer in memory
149 * @image: kexec image in which memory to search.
150 * @buffer: Contents which will be copied to the allocated memory.
151 * @bufsz: Size of @buffer.
152 * @mem: On return will have address of the buffer in memory.
153 * @memsz: Size for the buffer in memory.
154 * @buf_align: Minimum alignment needed.
155 * @buf_min: The buffer can't be placed below this address.
156 * @buf_max: The buffer can't be placed above this address.
157 * @top_down: Allocate from top of memory.
158 */
159 struct kexec_buf {
160 struct kimage *image;
161 void *buffer;
162 unsigned long bufsz;
163 unsigned long mem;
164 unsigned long memsz;
165 unsigned long buf_align;
166 unsigned long buf_min;
167 unsigned long buf_max;
168 bool top_down;
169 };
170
171 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
172 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
173 void *buf, unsigned int size,
174 bool get_value);
175 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
176
177 int __weak arch_kexec_apply_relocations_add(struct purgatory_info *pi,
178 Elf_Shdr *section,
179 const Elf_Shdr *relsec,
180 const Elf_Shdr *symtab);
181 int __weak arch_kexec_apply_relocations(struct purgatory_info *pi,
182 Elf_Shdr *section,
183 const Elf_Shdr *relsec,
184 const Elf_Shdr *symtab);
185
186 int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
187 int (*func)(struct resource *, void *));
188 extern int kexec_add_buffer(struct kexec_buf *kbuf);
189 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
190
191 /* Alignment required for elf header segment */
192 #define ELF_CORE_HEADER_ALIGN 4096
193
194 struct crash_mem_range {
195 u64 start, end;
196 };
197
198 struct crash_mem {
199 unsigned int max_nr_ranges;
200 unsigned int nr_ranges;
201 struct crash_mem_range ranges[0];
202 };
203
204 extern int crash_exclude_mem_range(struct crash_mem *mem,
205 unsigned long long mstart,
206 unsigned long long mend);
207 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
208 void **addr, unsigned long *sz);
209 #endif /* CONFIG_KEXEC_FILE */
210
211 struct kimage {
212 kimage_entry_t head;
213 kimage_entry_t *entry;
214 kimage_entry_t *last_entry;
215
216 unsigned long start;
217 struct page *control_code_page;
218 struct page *swap_page;
219 void *vmcoreinfo_data_copy; /* locates in the crash memory */
220
221 unsigned long nr_segments;
222 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
223
224 struct list_head control_pages;
225 struct list_head dest_pages;
226 struct list_head unusable_pages;
227
228 /* Address of next control page to allocate for crash kernels. */
229 unsigned long control_page;
230
231 /* Flags to indicate special processing */
232 unsigned int type : 1;
233 #define KEXEC_TYPE_DEFAULT 0
234 #define KEXEC_TYPE_CRASH 1
235 unsigned int preserve_context : 1;
236 /* If set, we are using file mode kexec syscall */
237 unsigned int file_mode:1;
238
239 #ifdef ARCH_HAS_KIMAGE_ARCH
240 struct kimage_arch arch;
241 #endif
242
243 #ifdef CONFIG_KEXEC_FILE
244 /* Additional fields for file based kexec syscall */
245 void *kernel_buf;
246 unsigned long kernel_buf_len;
247
248 void *initrd_buf;
249 unsigned long initrd_buf_len;
250
251 char *cmdline_buf;
252 unsigned long cmdline_buf_len;
253
254 /* File operations provided by image loader */
255 const struct kexec_file_ops *fops;
256
257 /* Image loader handling the kernel can store a pointer here */
258 void *image_loader_data;
259
260 /* Information for loading purgatory */
261 struct purgatory_info purgatory_info;
262 #endif
263 };
264
265 /* kexec interface functions */
266 extern void machine_kexec(struct kimage *image);
267 extern int machine_kexec_prepare(struct kimage *image);
268 extern void machine_kexec_cleanup(struct kimage *image);
269 extern int kernel_kexec(void);
270 extern struct page *kimage_alloc_control_pages(struct kimage *image,
271 unsigned int order);
272 extern void __crash_kexec(struct pt_regs *);
273 extern void crash_kexec(struct pt_regs *);
274 int kexec_should_crash(struct task_struct *);
275 int kexec_crash_loaded(void);
276 void crash_save_cpu(struct pt_regs *regs, int cpu);
277 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
278
279 extern struct kimage *kexec_image;
280 extern struct kimage *kexec_crash_image;
281 extern int kexec_load_disabled;
282
283 #ifndef kexec_flush_icache_page
284 #define kexec_flush_icache_page(page)
285 #endif
286
287 /* List of defined/legal kexec flags */
288 #ifndef CONFIG_KEXEC_JUMP
289 #define KEXEC_FLAGS KEXEC_ON_CRASH
290 #else
291 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
292 #endif
293
294 /* List of defined/legal kexec file flags */
295 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
296 KEXEC_FILE_NO_INITRAMFS)
297
298 /* Location of a reserved region to hold the crash kernel.
299 */
300 extern struct resource crashk_res;
301 extern struct resource crashk_low_res;
302 extern note_buf_t __percpu *crash_notes;
303
304 /* flag to track if kexec reboot is in progress */
305 extern bool kexec_in_progress;
306
307 int crash_shrink_memory(unsigned long new_size);
308 size_t crash_get_memory_size(void);
309 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
310
311 void arch_kexec_protect_crashkres(void);
312 void arch_kexec_unprotect_crashkres(void);
313
314 #ifndef page_to_boot_pfn
page_to_boot_pfn(struct page * page)315 static inline unsigned long page_to_boot_pfn(struct page *page)
316 {
317 return page_to_pfn(page);
318 }
319 #endif
320
321 #ifndef boot_pfn_to_page
boot_pfn_to_page(unsigned long boot_pfn)322 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
323 {
324 return pfn_to_page(boot_pfn);
325 }
326 #endif
327
328 #ifndef phys_to_boot_phys
phys_to_boot_phys(phys_addr_t phys)329 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
330 {
331 return phys;
332 }
333 #endif
334
335 #ifndef boot_phys_to_phys
boot_phys_to_phys(unsigned long boot_phys)336 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
337 {
338 return boot_phys;
339 }
340 #endif
341
virt_to_boot_phys(void * addr)342 static inline unsigned long virt_to_boot_phys(void *addr)
343 {
344 return phys_to_boot_phys(__pa((unsigned long)addr));
345 }
346
boot_phys_to_virt(unsigned long entry)347 static inline void *boot_phys_to_virt(unsigned long entry)
348 {
349 return phys_to_virt(boot_phys_to_phys(entry));
350 }
351
352 #ifndef arch_kexec_post_alloc_pages
arch_kexec_post_alloc_pages(void * vaddr,unsigned int pages,gfp_t gfp)353 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
354 #endif
355
356 #ifndef arch_kexec_pre_free_pages
arch_kexec_pre_free_pages(void * vaddr,unsigned int pages)357 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
358 #endif
359
360 #else /* !CONFIG_KEXEC_CORE */
361 struct pt_regs;
362 struct task_struct;
__crash_kexec(struct pt_regs * regs)363 static inline void __crash_kexec(struct pt_regs *regs) { }
crash_kexec(struct pt_regs * regs)364 static inline void crash_kexec(struct pt_regs *regs) { }
kexec_should_crash(struct task_struct * p)365 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
kexec_crash_loaded(void)366 static inline int kexec_crash_loaded(void) { return 0; }
367 #define kexec_in_progress false
368 #endif /* CONFIG_KEXEC_CORE */
369
370 #endif /* !defined(__ASSEBMLY__) */
371
372 #endif /* LINUX_KEXEC_H */
373
