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 #include <linux/verification.h>
23
24 /* Location of a reserved region to hold the crash kernel.
25 */
26 extern struct resource crashk_res;
27 extern struct resource crashk_low_res;
28 extern note_buf_t __percpu *crash_notes;
29
30 #ifdef CONFIG_KEXEC_CORE
31 #include <linux/list.h>
32 #include <linux/compat.h>
33 #include <linux/ioport.h>
34 #include <linux/module.h>
35 #include <asm/kexec.h>
36
37 /* Verify architecture specific macros are defined */
38
39 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
40 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
41 #endif
42
43 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
44 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
45 #endif
46
47 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
48 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
49 #endif
50
51 #ifndef KEXEC_CONTROL_MEMORY_GFP
52 #define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
53 #endif
54
55 #ifndef KEXEC_CONTROL_PAGE_SIZE
56 #error KEXEC_CONTROL_PAGE_SIZE not defined
57 #endif
58
59 #ifndef KEXEC_ARCH
60 #error KEXEC_ARCH not defined
61 #endif
62
63 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
64 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
65 #endif
66
67 #ifndef KEXEC_CRASH_MEM_ALIGN
68 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
69 #endif
70
71 #define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME
72
73 /*
74 * This structure is used to hold the arguments that are used when loading
75 * kernel binaries.
76 */
77
78 typedef unsigned long kimage_entry_t;
79
80 struct kexec_segment {
81 /*
82 * This pointer can point to user memory if kexec_load() system
83 * call is used or will point to kernel memory if
84 * kexec_file_load() system call is used.
85 *
86 * Use ->buf when expecting to deal with user memory and use ->kbuf
87 * when expecting to deal with kernel memory.
88 */
89 union {
90 void __user *buf;
91 void *kbuf;
92 };
93 size_t bufsz;
94 unsigned long mem;
95 size_t memsz;
96 };
97
98 #ifdef CONFIG_COMPAT
99 struct compat_kexec_segment {
100 compat_uptr_t buf;
101 compat_size_t bufsz;
102 compat_ulong_t mem; /* User space sees this as a (void *) ... */
103 compat_size_t memsz;
104 };
105 #endif
106
107 #ifdef CONFIG_KEXEC_FILE
108 struct purgatory_info {
109 /*
110 * Pointer to elf header at the beginning of kexec_purgatory.
111 * Note: kexec_purgatory is read only
112 */
113 const Elf_Ehdr *ehdr;
114 /*
115 * Temporary, modifiable buffer for sechdrs used for relocation.
116 * This memory can be freed post image load.
117 */
118 Elf_Shdr *sechdrs;
119 /*
120 * Temporary, modifiable buffer for stripped purgatory used for
121 * relocation. This memory can be freed post image load.
122 */
123 void *purgatory_buf;
124 };
125
126 struct kimage;
127
128 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
129 typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
130 unsigned long kernel_len, char *initrd,
131 unsigned long initrd_len, char *cmdline,
132 unsigned long cmdline_len);
133 typedef int (kexec_cleanup_t)(void *loader_data);
134
135 #ifdef CONFIG_KEXEC_SIG
136 typedef int (kexec_verify_sig_t)(const char *kernel_buf,
137 unsigned long kernel_len);
138 #endif
139
140 struct kexec_file_ops {
141 kexec_probe_t *probe;
142 kexec_load_t *load;
143 kexec_cleanup_t *cleanup;
144 #ifdef CONFIG_KEXEC_SIG
145 kexec_verify_sig_t *verify_sig;
146 #endif
147 };
148
149 extern const struct kexec_file_ops * const kexec_file_loaders[];
150
151 int kexec_image_probe_default(struct kimage *image, void *buf,
152 unsigned long buf_len);
153 int kexec_image_post_load_cleanup_default(struct kimage *image);
154
155 /*
156 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole()
157 * will try to allocate free memory. Arch may overwrite it.
158 */
159 #ifndef KEXEC_BUF_MEM_UNKNOWN
160 #define KEXEC_BUF_MEM_UNKNOWN 0
161 #endif
162
163 /**
164 * struct kexec_buf - parameters for finding a place for a buffer in memory
165 * @image: kexec image in which memory to search.
166 * @buffer: Contents which will be copied to the allocated memory.
167 * @bufsz: Size of @buffer.
168 * @mem: On return will have address of the buffer in memory.
169 * @memsz: Size for the buffer in memory.
170 * @buf_align: Minimum alignment needed.
171 * @buf_min: The buffer can't be placed below this address.
172 * @buf_max: The buffer can't be placed above this address.
173 * @top_down: Allocate from top of memory.
174 */
175 struct kexec_buf {
176 struct kimage *image;
177 void *buffer;
178 unsigned long bufsz;
179 unsigned long mem;
180 unsigned long memsz;
181 unsigned long buf_align;
182 unsigned long buf_min;
183 unsigned long buf_max;
184 bool top_down;
185 };
186
187 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
188 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
189 void *buf, unsigned int size,
190 bool get_value);
191 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
192 void *kexec_image_load_default(struct kimage *image);
193
194 #ifndef arch_kexec_kernel_image_probe
195 static inline int
arch_kexec_kernel_image_probe(struct kimage * image,void * buf,unsigned long buf_len)196 arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len)
197 {
198 return kexec_image_probe_default(image, buf, buf_len);
199 }
200 #endif
201
202 #ifndef arch_kimage_file_post_load_cleanup
arch_kimage_file_post_load_cleanup(struct kimage * image)203 static inline int arch_kimage_file_post_load_cleanup(struct kimage *image)
204 {
205 return kexec_image_post_load_cleanup_default(image);
206 }
207 #endif
208
209 #ifndef arch_kexec_kernel_image_load
arch_kexec_kernel_image_load(struct kimage * image)210 static inline void *arch_kexec_kernel_image_load(struct kimage *image)
211 {
212 return kexec_image_load_default(image);
213 }
214 #endif
215
216 #ifdef CONFIG_KEXEC_SIG
217 #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
218 int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len);
219 #endif
220 #endif
221
222 extern int kexec_add_buffer(struct kexec_buf *kbuf);
223 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
224
225 #ifndef arch_kexec_locate_mem_hole
226 /**
227 * arch_kexec_locate_mem_hole - Find free memory to place the segments.
228 * @kbuf: Parameters for the memory search.
229 *
230 * On success, kbuf->mem will have the start address of the memory region found.
231 *
232 * Return: 0 on success, negative errno on error.
233 */
arch_kexec_locate_mem_hole(struct kexec_buf * kbuf)234 static inline int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
235 {
236 return kexec_locate_mem_hole(kbuf);
237 }
238 #endif
239
240 /* Alignment required for elf header segment */
241 #define ELF_CORE_HEADER_ALIGN 4096
242
243 struct crash_mem_range {
244 u64 start, end;
245 };
246
247 struct crash_mem {
248 unsigned int max_nr_ranges;
249 unsigned int nr_ranges;
250 struct crash_mem_range ranges[];
251 };
252
253 extern int crash_exclude_mem_range(struct crash_mem *mem,
254 unsigned long long mstart,
255 unsigned long long mend);
256 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
257 void **addr, unsigned long *sz);
258
259 #ifndef arch_kexec_apply_relocations_add
260 /*
261 * arch_kexec_apply_relocations_add - apply relocations of type RELA
262 * @pi: Purgatory to be relocated.
263 * @section: Section relocations applying to.
264 * @relsec: Section containing RELAs.
265 * @symtab: Corresponding symtab.
266 *
267 * Return: 0 on success, negative errno on error.
268 */
269 static inline int
arch_kexec_apply_relocations_add(struct purgatory_info * pi,Elf_Shdr * section,const Elf_Shdr * relsec,const Elf_Shdr * symtab)270 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
271 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
272 {
273 pr_err("RELA relocation unsupported.\n");
274 return -ENOEXEC;
275 }
276 #endif
277
278 #ifndef arch_kexec_apply_relocations
279 /*
280 * arch_kexec_apply_relocations - apply relocations of type REL
281 * @pi: Purgatory to be relocated.
282 * @section: Section relocations applying to.
283 * @relsec: Section containing RELs.
284 * @symtab: Corresponding symtab.
285 *
286 * Return: 0 on success, negative errno on error.
287 */
288 static inline int
arch_kexec_apply_relocations(struct purgatory_info * pi,Elf_Shdr * section,const Elf_Shdr * relsec,const Elf_Shdr * symtab)289 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
290 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
291 {
292 pr_err("REL relocation unsupported.\n");
293 return -ENOEXEC;
294 }
295 #endif
296 #endif /* CONFIG_KEXEC_FILE */
297
298 #ifdef CONFIG_KEXEC_ELF
299 struct kexec_elf_info {
300 /*
301 * Where the ELF binary contents are kept.
302 * Memory managed by the user of the struct.
303 */
304 const char *buffer;
305
306 const struct elfhdr *ehdr;
307 const struct elf_phdr *proghdrs;
308 };
309
310 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
311 struct kexec_elf_info *elf_info);
312
313 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
314 struct kexec_elf_info *elf_info,
315 struct kexec_buf *kbuf,
316 unsigned long *lowest_load_addr);
317
318 void kexec_free_elf_info(struct kexec_elf_info *elf_info);
319 int kexec_elf_probe(const char *buf, unsigned long len);
320 #endif
321 struct kimage {
322 kimage_entry_t head;
323 kimage_entry_t *entry;
324 kimage_entry_t *last_entry;
325
326 unsigned long start;
327 struct page *control_code_page;
328 struct page *swap_page;
329 void *vmcoreinfo_data_copy; /* locates in the crash memory */
330
331 unsigned long nr_segments;
332 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
333
334 struct list_head control_pages;
335 struct list_head dest_pages;
336 struct list_head unusable_pages;
337
338 /* Address of next control page to allocate for crash kernels. */
339 unsigned long control_page;
340
341 /* Flags to indicate special processing */
342 unsigned int type : 1;
343 #define KEXEC_TYPE_DEFAULT 0
344 #define KEXEC_TYPE_CRASH 1
345 unsigned int preserve_context : 1;
346 /* If set, we are using file mode kexec syscall */
347 unsigned int file_mode:1;
348
349 #ifdef ARCH_HAS_KIMAGE_ARCH
350 struct kimage_arch arch;
351 #endif
352
353 #ifdef CONFIG_KEXEC_FILE
354 /* Additional fields for file based kexec syscall */
355 void *kernel_buf;
356 unsigned long kernel_buf_len;
357
358 void *initrd_buf;
359 unsigned long initrd_buf_len;
360
361 char *cmdline_buf;
362 unsigned long cmdline_buf_len;
363
364 /* File operations provided by image loader */
365 const struct kexec_file_ops *fops;
366
367 /* Image loader handling the kernel can store a pointer here */
368 void *image_loader_data;
369
370 /* Information for loading purgatory */
371 struct purgatory_info purgatory_info;
372 #endif
373
374 #ifdef CONFIG_IMA_KEXEC
375 /* Virtual address of IMA measurement buffer for kexec syscall */
376 void *ima_buffer;
377
378 phys_addr_t ima_buffer_addr;
379 size_t ima_buffer_size;
380 #endif
381
382 /* Core ELF header buffer */
383 void *elf_headers;
384 unsigned long elf_headers_sz;
385 unsigned long elf_load_addr;
386 };
387
388 /* kexec interface functions */
389 extern void machine_kexec(struct kimage *image);
390 extern int machine_kexec_prepare(struct kimage *image);
391 extern void machine_kexec_cleanup(struct kimage *image);
392 extern int kernel_kexec(void);
393 extern struct page *kimage_alloc_control_pages(struct kimage *image,
394 unsigned int order);
395
396 #ifndef machine_kexec_post_load
machine_kexec_post_load(struct kimage * image)397 static inline int machine_kexec_post_load(struct kimage *image) { return 0; }
398 #endif
399
400 extern void __crash_kexec(struct pt_regs *);
401 extern void crash_kexec(struct pt_regs *);
402 int kexec_should_crash(struct task_struct *);
403 int kexec_crash_loaded(void);
404 void crash_save_cpu(struct pt_regs *regs, int cpu);
405 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
406
407 extern struct kimage *kexec_image;
408 extern struct kimage *kexec_crash_image;
409 extern int kexec_load_disabled;
410
411 #ifndef kexec_flush_icache_page
412 #define kexec_flush_icache_page(page)
413 #endif
414
415 /* List of defined/legal kexec flags */
416 #ifndef CONFIG_KEXEC_JUMP
417 #define KEXEC_FLAGS KEXEC_ON_CRASH
418 #else
419 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
420 #endif
421
422 /* List of defined/legal kexec file flags */
423 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
424 KEXEC_FILE_NO_INITRAMFS)
425
426 /* flag to track if kexec reboot is in progress */
427 extern bool kexec_in_progress;
428
429 int crash_shrink_memory(unsigned long new_size);
430 ssize_t crash_get_memory_size(void);
431
432 #ifndef arch_kexec_protect_crashkres
433 /*
434 * Protection mechanism for crashkernel reserved memory after
435 * the kdump kernel is loaded.
436 *
437 * Provide an empty default implementation here -- architecture
438 * code may override this
439 */
arch_kexec_protect_crashkres(void)440 static inline void arch_kexec_protect_crashkres(void) { }
441 #endif
442
443 #ifndef arch_kexec_unprotect_crashkres
arch_kexec_unprotect_crashkres(void)444 static inline void arch_kexec_unprotect_crashkres(void) { }
445 #endif
446
447 #ifndef page_to_boot_pfn
page_to_boot_pfn(struct page * page)448 static inline unsigned long page_to_boot_pfn(struct page *page)
449 {
450 return page_to_pfn(page);
451 }
452 #endif
453
454 #ifndef boot_pfn_to_page
boot_pfn_to_page(unsigned long boot_pfn)455 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
456 {
457 return pfn_to_page(boot_pfn);
458 }
459 #endif
460
461 #ifndef phys_to_boot_phys
phys_to_boot_phys(phys_addr_t phys)462 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
463 {
464 return phys;
465 }
466 #endif
467
468 #ifndef boot_phys_to_phys
boot_phys_to_phys(unsigned long boot_phys)469 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
470 {
471 return boot_phys;
472 }
473 #endif
474
475 #ifndef crash_free_reserved_phys_range
crash_free_reserved_phys_range(unsigned long begin,unsigned long end)476 static inline void crash_free_reserved_phys_range(unsigned long begin, unsigned long end)
477 {
478 unsigned long addr;
479
480 for (addr = begin; addr < end; addr += PAGE_SIZE)
481 free_reserved_page(boot_pfn_to_page(addr >> PAGE_SHIFT));
482 }
483 #endif
484
virt_to_boot_phys(void * addr)485 static inline unsigned long virt_to_boot_phys(void *addr)
486 {
487 return phys_to_boot_phys(__pa((unsigned long)addr));
488 }
489
boot_phys_to_virt(unsigned long entry)490 static inline void *boot_phys_to_virt(unsigned long entry)
491 {
492 return phys_to_virt(boot_phys_to_phys(entry));
493 }
494
495 #ifndef arch_kexec_post_alloc_pages
arch_kexec_post_alloc_pages(void * vaddr,unsigned int pages,gfp_t gfp)496 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
497 #endif
498
499 #ifndef arch_kexec_pre_free_pages
arch_kexec_pre_free_pages(void * vaddr,unsigned int pages)500 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
501 #endif
502
503 #else /* !CONFIG_KEXEC_CORE */
504 struct pt_regs;
505 struct task_struct;
__crash_kexec(struct pt_regs * regs)506 static inline void __crash_kexec(struct pt_regs *regs) { }
crash_kexec(struct pt_regs * regs)507 static inline void crash_kexec(struct pt_regs *regs) { }
kexec_should_crash(struct task_struct * p)508 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
kexec_crash_loaded(void)509 static inline int kexec_crash_loaded(void) { return 0; }
510 #define kexec_in_progress false
511 #endif /* CONFIG_KEXEC_CORE */
512
513 #ifdef CONFIG_KEXEC_SIG
514 void set_kexec_sig_enforced(void);
515 #else
set_kexec_sig_enforced(void)516 static inline void set_kexec_sig_enforced(void) {}
517 #endif
518
519 #endif /* !defined(__ASSEBMLY__) */
520
521 #endif /* LINUX_KEXEC_H */
522