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_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_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 int kexec_image_post_load_cleanup_default(struct kimage *image);
147
148 /*
149 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole()
150 * will try to allocate free memory. Arch may overwrite it.
151 */
152 #ifndef KEXEC_BUF_MEM_UNKNOWN
153 #define KEXEC_BUF_MEM_UNKNOWN 0
154 #endif
155
156 /**
157 * struct kexec_buf - parameters for finding a place for a buffer in memory
158 * @image: kexec image in which memory to search.
159 * @buffer: Contents which will be copied to the allocated memory.
160 * @bufsz: Size of @buffer.
161 * @mem: On return will have address of the buffer in memory.
162 * @memsz: Size for the buffer in memory.
163 * @buf_align: Minimum alignment needed.
164 * @buf_min: The buffer can't be placed below this address.
165 * @buf_max: The buffer can't be placed above this address.
166 * @top_down: Allocate from top of memory.
167 */
168 struct kexec_buf {
169 struct kimage *image;
170 void *buffer;
171 unsigned long bufsz;
172 unsigned long mem;
173 unsigned long memsz;
174 unsigned long buf_align;
175 unsigned long buf_min;
176 unsigned long buf_max;
177 bool top_down;
178 };
179
180 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
181 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
182 void *buf, unsigned int size,
183 bool get_value);
184 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
185
186 /* Architectures may override the below functions */
187 int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
188 unsigned long buf_len);
189 void *arch_kexec_kernel_image_load(struct kimage *image);
190 int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
191 Elf_Shdr *section,
192 const Elf_Shdr *relsec,
193 const Elf_Shdr *symtab);
194 int arch_kexec_apply_relocations(struct purgatory_info *pi,
195 Elf_Shdr *section,
196 const Elf_Shdr *relsec,
197 const Elf_Shdr *symtab);
198 int arch_kimage_file_post_load_cleanup(struct kimage *image);
199 #ifdef CONFIG_KEXEC_SIG
200 int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
201 unsigned long buf_len);
202 #endif
203 int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
204
205 extern int kexec_add_buffer(struct kexec_buf *kbuf);
206 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
207
208 /* Alignment required for elf header segment */
209 #define ELF_CORE_HEADER_ALIGN 4096
210
211 struct crash_mem_range {
212 u64 start, end;
213 };
214
215 struct crash_mem {
216 unsigned int max_nr_ranges;
217 unsigned int nr_ranges;
218 struct crash_mem_range ranges[];
219 };
220
221 extern int crash_exclude_mem_range(struct crash_mem *mem,
222 unsigned long long mstart,
223 unsigned long long mend);
224 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
225 void **addr, unsigned long *sz);
226 #endif /* CONFIG_KEXEC_FILE */
227
228 #ifdef CONFIG_KEXEC_ELF
229 struct kexec_elf_info {
230 /*
231 * Where the ELF binary contents are kept.
232 * Memory managed by the user of the struct.
233 */
234 const char *buffer;
235
236 const struct elfhdr *ehdr;
237 const struct elf_phdr *proghdrs;
238 };
239
240 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
241 struct kexec_elf_info *elf_info);
242
243 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
244 struct kexec_elf_info *elf_info,
245 struct kexec_buf *kbuf,
246 unsigned long *lowest_load_addr);
247
248 void kexec_free_elf_info(struct kexec_elf_info *elf_info);
249 int kexec_elf_probe(const char *buf, unsigned long len);
250 #endif
251 struct kimage {
252 kimage_entry_t head;
253 kimage_entry_t *entry;
254 kimage_entry_t *last_entry;
255
256 unsigned long start;
257 struct page *control_code_page;
258 struct page *swap_page;
259 void *vmcoreinfo_data_copy; /* locates in the crash memory */
260
261 unsigned long nr_segments;
262 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
263
264 struct list_head control_pages;
265 struct list_head dest_pages;
266 struct list_head unusable_pages;
267
268 /* Address of next control page to allocate for crash kernels. */
269 unsigned long control_page;
270
271 /* Flags to indicate special processing */
272 unsigned int type : 1;
273 #define KEXEC_TYPE_DEFAULT 0
274 #define KEXEC_TYPE_CRASH 1
275 unsigned int preserve_context : 1;
276 /* If set, we are using file mode kexec syscall */
277 unsigned int file_mode:1;
278
279 #ifdef ARCH_HAS_KIMAGE_ARCH
280 struct kimage_arch arch;
281 #endif
282
283 #ifdef CONFIG_KEXEC_FILE
284 /* Additional fields for file based kexec syscall */
285 void *kernel_buf;
286 unsigned long kernel_buf_len;
287
288 void *initrd_buf;
289 unsigned long initrd_buf_len;
290
291 char *cmdline_buf;
292 unsigned long cmdline_buf_len;
293
294 /* File operations provided by image loader */
295 const struct kexec_file_ops *fops;
296
297 /* Image loader handling the kernel can store a pointer here */
298 void *image_loader_data;
299
300 /* Information for loading purgatory */
301 struct purgatory_info purgatory_info;
302 #endif
303 };
304
305 /* kexec interface functions */
306 extern void machine_kexec(struct kimage *image);
307 extern int machine_kexec_prepare(struct kimage *image);
308 extern void machine_kexec_cleanup(struct kimage *image);
309 extern int kernel_kexec(void);
310 extern struct page *kimage_alloc_control_pages(struct kimage *image,
311 unsigned int order);
312 extern void __crash_kexec(struct pt_regs *);
313 extern void crash_kexec(struct pt_regs *);
314 int kexec_should_crash(struct task_struct *);
315 int kexec_crash_loaded(void);
316 void crash_save_cpu(struct pt_regs *regs, int cpu);
317 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
318
319 extern struct kimage *kexec_image;
320 extern struct kimage *kexec_crash_image;
321 extern int kexec_load_disabled;
322
323 #ifndef kexec_flush_icache_page
324 #define kexec_flush_icache_page(page)
325 #endif
326
327 /* List of defined/legal kexec flags */
328 #ifndef CONFIG_KEXEC_JUMP
329 #define KEXEC_FLAGS KEXEC_ON_CRASH
330 #else
331 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
332 #endif
333
334 /* List of defined/legal kexec file flags */
335 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
336 KEXEC_FILE_NO_INITRAMFS)
337
338 /* Location of a reserved region to hold the crash kernel.
339 */
340 extern struct resource crashk_res;
341 extern struct resource crashk_low_res;
342 extern note_buf_t __percpu *crash_notes;
343
344 /* flag to track if kexec reboot is in progress */
345 extern bool kexec_in_progress;
346
347 int crash_shrink_memory(unsigned long new_size);
348 size_t crash_get_memory_size(void);
349 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
350
351 void arch_kexec_protect_crashkres(void);
352 void arch_kexec_unprotect_crashkres(void);
353
354 #ifndef page_to_boot_pfn
page_to_boot_pfn(struct page * page)355 static inline unsigned long page_to_boot_pfn(struct page *page)
356 {
357 return page_to_pfn(page);
358 }
359 #endif
360
361 #ifndef boot_pfn_to_page
boot_pfn_to_page(unsigned long boot_pfn)362 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
363 {
364 return pfn_to_page(boot_pfn);
365 }
366 #endif
367
368 #ifndef phys_to_boot_phys
phys_to_boot_phys(phys_addr_t phys)369 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
370 {
371 return phys;
372 }
373 #endif
374
375 #ifndef boot_phys_to_phys
boot_phys_to_phys(unsigned long boot_phys)376 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
377 {
378 return boot_phys;
379 }
380 #endif
381
virt_to_boot_phys(void * addr)382 static inline unsigned long virt_to_boot_phys(void *addr)
383 {
384 return phys_to_boot_phys(__pa((unsigned long)addr));
385 }
386
boot_phys_to_virt(unsigned long entry)387 static inline void *boot_phys_to_virt(unsigned long entry)
388 {
389 return phys_to_virt(boot_phys_to_phys(entry));
390 }
391
392 #ifndef arch_kexec_post_alloc_pages
arch_kexec_post_alloc_pages(void * vaddr,unsigned int pages,gfp_t gfp)393 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
394 #endif
395
396 #ifndef arch_kexec_pre_free_pages
arch_kexec_pre_free_pages(void * vaddr,unsigned int pages)397 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
398 #endif
399
400 #else /* !CONFIG_KEXEC_CORE */
401 struct pt_regs;
402 struct task_struct;
__crash_kexec(struct pt_regs * regs)403 static inline void __crash_kexec(struct pt_regs *regs) { }
crash_kexec(struct pt_regs * regs)404 static inline void crash_kexec(struct pt_regs *regs) { }
kexec_should_crash(struct task_struct * p)405 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
kexec_crash_loaded(void)406 static inline int kexec_crash_loaded(void) { return 0; }
407 #define kexec_in_progress false
408 #endif /* CONFIG_KEXEC_CORE */
409
410 #endif /* !defined(__ASSEBMLY__) */
411
412 #endif /* LINUX_KEXEC_H */
413
