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_kimage_file_post_load_cleanup(struct kimage *image);
191 #ifdef CONFIG_KEXEC_SIG
192 int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
193 unsigned long buf_len);
194 #endif
195 int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
196
197 extern int kexec_add_buffer(struct kexec_buf *kbuf);
198 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
199
200 /* Alignment required for elf header segment */
201 #define ELF_CORE_HEADER_ALIGN 4096
202
203 struct crash_mem_range {
204 u64 start, end;
205 };
206
207 struct crash_mem {
208 unsigned int max_nr_ranges;
209 unsigned int nr_ranges;
210 struct crash_mem_range ranges[];
211 };
212
213 extern int crash_exclude_mem_range(struct crash_mem *mem,
214 unsigned long long mstart,
215 unsigned long long mend);
216 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
217 void **addr, unsigned long *sz);
218
219 #ifndef arch_kexec_apply_relocations_add
220 /*
221 * arch_kexec_apply_relocations_add - apply relocations of type RELA
222 * @pi: Purgatory to be relocated.
223 * @section: Section relocations applying to.
224 * @relsec: Section containing RELAs.
225 * @symtab: Corresponding symtab.
226 *
227 * Return: 0 on success, negative errno on error.
228 */
229 static inline int
arch_kexec_apply_relocations_add(struct purgatory_info * pi,Elf_Shdr * section,const Elf_Shdr * relsec,const Elf_Shdr * symtab)230 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
231 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
232 {
233 pr_err("RELA relocation unsupported.\n");
234 return -ENOEXEC;
235 }
236 #endif
237
238 #ifndef arch_kexec_apply_relocations
239 /*
240 * arch_kexec_apply_relocations - apply relocations of type REL
241 * @pi: Purgatory to be relocated.
242 * @section: Section relocations applying to.
243 * @relsec: Section containing RELs.
244 * @symtab: Corresponding symtab.
245 *
246 * Return: 0 on success, negative errno on error.
247 */
248 static inline int
arch_kexec_apply_relocations(struct purgatory_info * pi,Elf_Shdr * section,const Elf_Shdr * relsec,const Elf_Shdr * symtab)249 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
250 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
251 {
252 pr_err("REL relocation unsupported.\n");
253 return -ENOEXEC;
254 }
255 #endif
256 #endif /* CONFIG_KEXEC_FILE */
257
258 #ifdef CONFIG_KEXEC_ELF
259 struct kexec_elf_info {
260 /*
261 * Where the ELF binary contents are kept.
262 * Memory managed by the user of the struct.
263 */
264 const char *buffer;
265
266 const struct elfhdr *ehdr;
267 const struct elf_phdr *proghdrs;
268 };
269
270 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
271 struct kexec_elf_info *elf_info);
272
273 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
274 struct kexec_elf_info *elf_info,
275 struct kexec_buf *kbuf,
276 unsigned long *lowest_load_addr);
277
278 void kexec_free_elf_info(struct kexec_elf_info *elf_info);
279 int kexec_elf_probe(const char *buf, unsigned long len);
280 #endif
281 struct kimage {
282 kimage_entry_t head;
283 kimage_entry_t *entry;
284 kimage_entry_t *last_entry;
285
286 unsigned long start;
287 struct page *control_code_page;
288 struct page *swap_page;
289 void *vmcoreinfo_data_copy; /* locates in the crash memory */
290
291 unsigned long nr_segments;
292 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
293
294 struct list_head control_pages;
295 struct list_head dest_pages;
296 struct list_head unusable_pages;
297
298 /* Address of next control page to allocate for crash kernels. */
299 unsigned long control_page;
300
301 /* Flags to indicate special processing */
302 unsigned int type : 1;
303 #define KEXEC_TYPE_DEFAULT 0
304 #define KEXEC_TYPE_CRASH 1
305 unsigned int preserve_context : 1;
306 /* If set, we are using file mode kexec syscall */
307 unsigned int file_mode:1;
308
309 #ifdef ARCH_HAS_KIMAGE_ARCH
310 struct kimage_arch arch;
311 #endif
312
313 #ifdef CONFIG_KEXEC_FILE
314 /* Additional fields for file based kexec syscall */
315 void *kernel_buf;
316 unsigned long kernel_buf_len;
317
318 void *initrd_buf;
319 unsigned long initrd_buf_len;
320
321 char *cmdline_buf;
322 unsigned long cmdline_buf_len;
323
324 /* File operations provided by image loader */
325 const struct kexec_file_ops *fops;
326
327 /* Image loader handling the kernel can store a pointer here */
328 void *image_loader_data;
329
330 /* Information for loading purgatory */
331 struct purgatory_info purgatory_info;
332 #endif
333
334 #ifdef CONFIG_IMA_KEXEC
335 /* Virtual address of IMA measurement buffer for kexec syscall */
336 void *ima_buffer;
337
338 phys_addr_t ima_buffer_addr;
339 size_t ima_buffer_size;
340 #endif
341
342 /* Core ELF header buffer */
343 void *elf_headers;
344 unsigned long elf_headers_sz;
345 unsigned long elf_load_addr;
346 };
347
348 /* kexec interface functions */
349 extern void machine_kexec(struct kimage *image);
350 extern int machine_kexec_prepare(struct kimage *image);
351 extern void machine_kexec_cleanup(struct kimage *image);
352 extern int kernel_kexec(void);
353 extern struct page *kimage_alloc_control_pages(struct kimage *image,
354 unsigned int order);
355 int machine_kexec_post_load(struct kimage *image);
356
357 extern void __crash_kexec(struct pt_regs *);
358 extern void crash_kexec(struct pt_regs *);
359 int kexec_should_crash(struct task_struct *);
360 int kexec_crash_loaded(void);
361 void crash_save_cpu(struct pt_regs *regs, int cpu);
362 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
363
364 extern struct kimage *kexec_image;
365 extern struct kimage *kexec_crash_image;
366 extern int kexec_load_disabled;
367
368 #ifndef kexec_flush_icache_page
369 #define kexec_flush_icache_page(page)
370 #endif
371
372 /* List of defined/legal kexec flags */
373 #ifndef CONFIG_KEXEC_JUMP
374 #define KEXEC_FLAGS KEXEC_ON_CRASH
375 #else
376 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
377 #endif
378
379 /* List of defined/legal kexec file flags */
380 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
381 KEXEC_FILE_NO_INITRAMFS)
382
383 /* Location of a reserved region to hold the crash kernel.
384 */
385 extern struct resource crashk_res;
386 extern struct resource crashk_low_res;
387 extern note_buf_t __percpu *crash_notes;
388
389 /* flag to track if kexec reboot is in progress */
390 extern bool kexec_in_progress;
391
392 int crash_shrink_memory(unsigned long new_size);
393 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
394 ssize_t crash_get_memory_size(void);
395
396 void arch_kexec_protect_crashkres(void);
397 void arch_kexec_unprotect_crashkres(void);
398
399 #ifndef page_to_boot_pfn
page_to_boot_pfn(struct page * page)400 static inline unsigned long page_to_boot_pfn(struct page *page)
401 {
402 return page_to_pfn(page);
403 }
404 #endif
405
406 #ifndef boot_pfn_to_page
boot_pfn_to_page(unsigned long boot_pfn)407 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
408 {
409 return pfn_to_page(boot_pfn);
410 }
411 #endif
412
413 #ifndef phys_to_boot_phys
phys_to_boot_phys(phys_addr_t phys)414 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
415 {
416 return phys;
417 }
418 #endif
419
420 #ifndef boot_phys_to_phys
boot_phys_to_phys(unsigned long boot_phys)421 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
422 {
423 return boot_phys;
424 }
425 #endif
426
virt_to_boot_phys(void * addr)427 static inline unsigned long virt_to_boot_phys(void *addr)
428 {
429 return phys_to_boot_phys(__pa((unsigned long)addr));
430 }
431
boot_phys_to_virt(unsigned long entry)432 static inline void *boot_phys_to_virt(unsigned long entry)
433 {
434 return phys_to_virt(boot_phys_to_phys(entry));
435 }
436
437 #ifndef arch_kexec_post_alloc_pages
arch_kexec_post_alloc_pages(void * vaddr,unsigned int pages,gfp_t gfp)438 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
439 #endif
440
441 #ifndef arch_kexec_pre_free_pages
arch_kexec_pre_free_pages(void * vaddr,unsigned int pages)442 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
443 #endif
444
445 #else /* !CONFIG_KEXEC_CORE */
446 struct pt_regs;
447 struct task_struct;
__crash_kexec(struct pt_regs * regs)448 static inline void __crash_kexec(struct pt_regs *regs) { }
crash_kexec(struct pt_regs * regs)449 static inline void crash_kexec(struct pt_regs *regs) { }
kexec_should_crash(struct task_struct * p)450 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
kexec_crash_loaded(void)451 static inline int kexec_crash_loaded(void) { return 0; }
452 #define kexec_in_progress false
453 #endif /* CONFIG_KEXEC_CORE */
454
455 #ifdef CONFIG_KEXEC_SIG
456 void set_kexec_sig_enforced(void);
457 #else
set_kexec_sig_enforced(void)458 static inline void set_kexec_sig_enforced(void) {}
459 #endif
460
461 #endif /* !defined(__ASSEBMLY__) */
462
463 #endif /* LINUX_KEXEC_H */
464