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 int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
187 unsigned long buf_len);
188 void * __weak arch_kexec_kernel_image_load(struct kimage *image);
189 int __weak arch_kexec_apply_relocations_add(struct purgatory_info *pi,
190 Elf_Shdr *section,
191 const Elf_Shdr *relsec,
192 const Elf_Shdr *symtab);
193 int __weak arch_kexec_apply_relocations(struct purgatory_info *pi,
194 Elf_Shdr *section,
195 const Elf_Shdr *relsec,
196 const Elf_Shdr *symtab);
197
198 extern int kexec_add_buffer(struct kexec_buf *kbuf);
199 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
200
201 /* Alignment required for elf header segment */
202 #define ELF_CORE_HEADER_ALIGN 4096
203
204 struct crash_mem_range {
205 u64 start, end;
206 };
207
208 struct crash_mem {
209 unsigned int max_nr_ranges;
210 unsigned int nr_ranges;
211 struct crash_mem_range ranges[0];
212 };
213
214 extern int crash_exclude_mem_range(struct crash_mem *mem,
215 unsigned long long mstart,
216 unsigned long long mend);
217 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
218 void **addr, unsigned long *sz);
219 #endif /* CONFIG_KEXEC_FILE */
220
221 #ifdef CONFIG_KEXEC_ELF
222 struct kexec_elf_info {
223 /*
224 * Where the ELF binary contents are kept.
225 * Memory managed by the user of the struct.
226 */
227 const char *buffer;
228
229 const struct elfhdr *ehdr;
230 const struct elf_phdr *proghdrs;
231 };
232
233 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
234 struct kexec_elf_info *elf_info);
235
236 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
237 struct kexec_elf_info *elf_info,
238 struct kexec_buf *kbuf,
239 unsigned long *lowest_load_addr);
240
241 void kexec_free_elf_info(struct kexec_elf_info *elf_info);
242 int kexec_elf_probe(const char *buf, unsigned long len);
243 #endif
244 struct kimage {
245 kimage_entry_t head;
246 kimage_entry_t *entry;
247 kimage_entry_t *last_entry;
248
249 unsigned long start;
250 struct page *control_code_page;
251 struct page *swap_page;
252 void *vmcoreinfo_data_copy; /* locates in the crash memory */
253
254 unsigned long nr_segments;
255 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
256
257 struct list_head control_pages;
258 struct list_head dest_pages;
259 struct list_head unusable_pages;
260
261 /* Address of next control page to allocate for crash kernels. */
262 unsigned long control_page;
263
264 /* Flags to indicate special processing */
265 unsigned int type : 1;
266 #define KEXEC_TYPE_DEFAULT 0
267 #define KEXEC_TYPE_CRASH 1
268 unsigned int preserve_context : 1;
269 /* If set, we are using file mode kexec syscall */
270 unsigned int file_mode:1;
271
272 #ifdef ARCH_HAS_KIMAGE_ARCH
273 struct kimage_arch arch;
274 #endif
275
276 #ifdef CONFIG_KEXEC_FILE
277 /* Additional fields for file based kexec syscall */
278 void *kernel_buf;
279 unsigned long kernel_buf_len;
280
281 void *initrd_buf;
282 unsigned long initrd_buf_len;
283
284 char *cmdline_buf;
285 unsigned long cmdline_buf_len;
286
287 /* File operations provided by image loader */
288 const struct kexec_file_ops *fops;
289
290 /* Image loader handling the kernel can store a pointer here */
291 void *image_loader_data;
292
293 /* Information for loading purgatory */
294 struct purgatory_info purgatory_info;
295 #endif
296 };
297
298 /* kexec interface functions */
299 extern void machine_kexec(struct kimage *image);
300 extern int machine_kexec_prepare(struct kimage *image);
301 extern void machine_kexec_cleanup(struct kimage *image);
302 extern int kernel_kexec(void);
303 extern struct page *kimage_alloc_control_pages(struct kimage *image,
304 unsigned int order);
305 extern void __crash_kexec(struct pt_regs *);
306 extern void crash_kexec(struct pt_regs *);
307 int kexec_should_crash(struct task_struct *);
308 int kexec_crash_loaded(void);
309 void crash_save_cpu(struct pt_regs *regs, int cpu);
310 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
311
312 extern struct kimage *kexec_image;
313 extern struct kimage *kexec_crash_image;
314 extern int kexec_load_disabled;
315
316 #ifndef kexec_flush_icache_page
317 #define kexec_flush_icache_page(page)
318 #endif
319
320 /* List of defined/legal kexec flags */
321 #ifndef CONFIG_KEXEC_JUMP
322 #define KEXEC_FLAGS KEXEC_ON_CRASH
323 #else
324 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
325 #endif
326
327 /* List of defined/legal kexec file flags */
328 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
329 KEXEC_FILE_NO_INITRAMFS)
330
331 /* Location of a reserved region to hold the crash kernel.
332 */
333 extern struct resource crashk_res;
334 extern struct resource crashk_low_res;
335 extern note_buf_t __percpu *crash_notes;
336
337 /* flag to track if kexec reboot is in progress */
338 extern bool kexec_in_progress;
339
340 int crash_shrink_memory(unsigned long new_size);
341 size_t crash_get_memory_size(void);
342 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
343
344 void arch_kexec_protect_crashkres(void);
345 void arch_kexec_unprotect_crashkres(void);
346
347 #ifndef page_to_boot_pfn
page_to_boot_pfn(struct page * page)348 static inline unsigned long page_to_boot_pfn(struct page *page)
349 {
350 return page_to_pfn(page);
351 }
352 #endif
353
354 #ifndef boot_pfn_to_page
boot_pfn_to_page(unsigned long boot_pfn)355 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
356 {
357 return pfn_to_page(boot_pfn);
358 }
359 #endif
360
361 #ifndef phys_to_boot_phys
phys_to_boot_phys(phys_addr_t phys)362 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
363 {
364 return phys;
365 }
366 #endif
367
368 #ifndef boot_phys_to_phys
boot_phys_to_phys(unsigned long boot_phys)369 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
370 {
371 return boot_phys;
372 }
373 #endif
374
virt_to_boot_phys(void * addr)375 static inline unsigned long virt_to_boot_phys(void *addr)
376 {
377 return phys_to_boot_phys(__pa((unsigned long)addr));
378 }
379
boot_phys_to_virt(unsigned long entry)380 static inline void *boot_phys_to_virt(unsigned long entry)
381 {
382 return phys_to_virt(boot_phys_to_phys(entry));
383 }
384
385 #ifndef arch_kexec_post_alloc_pages
arch_kexec_post_alloc_pages(void * vaddr,unsigned int pages,gfp_t gfp)386 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
387 #endif
388
389 #ifndef arch_kexec_pre_free_pages
arch_kexec_pre_free_pages(void * vaddr,unsigned int pages)390 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
391 #endif
392
393 #else /* !CONFIG_KEXEC_CORE */
394 struct pt_regs;
395 struct task_struct;
__crash_kexec(struct pt_regs * regs)396 static inline void __crash_kexec(struct pt_regs *regs) { }
crash_kexec(struct pt_regs * regs)397 static inline void crash_kexec(struct pt_regs *regs) { }
kexec_should_crash(struct task_struct * p)398 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
kexec_crash_loaded(void)399 static inline int kexec_crash_loaded(void) { return 0; }
400 #define kexec_in_progress false
401 #endif /* CONFIG_KEXEC_CORE */
402
403 #endif /* !defined(__ASSEBMLY__) */
404
405 #endif /* LINUX_KEXEC_H */
406
