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 #include <linux/range.h>
21
22 #include <uapi/linux/kexec.h>
23 #include <linux/verification.h>
24
25 /* Location of a reserved region to hold the crash kernel.
26 */
27 extern struct resource crashk_res;
28 extern struct resource crashk_low_res;
29 extern note_buf_t __percpu *crash_notes;
30
31 #ifdef CONFIG_KEXEC_CORE
32 #include <linux/list.h>
33 #include <linux/compat.h>
34 #include <linux/ioport.h>
35 #include <linux/module.h>
36 #include <linux/highmem.h>
37 #include <asm/kexec.h>
38
39 /* Verify architecture specific macros are defined */
40
41 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
42 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
43 #endif
44
45 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
46 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
47 #endif
48
49 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
50 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
51 #endif
52
53 #ifndef KEXEC_CONTROL_MEMORY_GFP
54 #define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
55 #endif
56
57 #ifndef KEXEC_CONTROL_PAGE_SIZE
58 #error KEXEC_CONTROL_PAGE_SIZE not defined
59 #endif
60
61 #ifndef KEXEC_ARCH
62 #error KEXEC_ARCH not defined
63 #endif
64
65 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
66 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
67 #endif
68
69 #ifndef KEXEC_CRASH_MEM_ALIGN
70 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
71 #endif
72
73 #define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME
74
75 /*
76 * This structure is used to hold the arguments that are used when loading
77 * kernel binaries.
78 */
79
80 typedef unsigned long kimage_entry_t;
81
82 struct kexec_segment {
83 /*
84 * This pointer can point to user memory if kexec_load() system
85 * call is used or will point to kernel memory if
86 * kexec_file_load() system call is used.
87 *
88 * Use ->buf when expecting to deal with user memory and use ->kbuf
89 * when expecting to deal with kernel memory.
90 */
91 union {
92 void __user *buf;
93 void *kbuf;
94 };
95 size_t bufsz;
96 unsigned long mem;
97 size_t memsz;
98 };
99
100 #ifdef CONFIG_COMPAT
101 struct compat_kexec_segment {
102 compat_uptr_t buf;
103 compat_size_t bufsz;
104 compat_ulong_t mem; /* User space sees this as a (void *) ... */
105 compat_size_t memsz;
106 };
107 #endif
108
109 #ifdef CONFIG_KEXEC_FILE
110 struct purgatory_info {
111 /*
112 * Pointer to elf header at the beginning of kexec_purgatory.
113 * Note: kexec_purgatory is read only
114 */
115 const Elf_Ehdr *ehdr;
116 /*
117 * Temporary, modifiable buffer for sechdrs used for relocation.
118 * This memory can be freed post image load.
119 */
120 Elf_Shdr *sechdrs;
121 /*
122 * Temporary, modifiable buffer for stripped purgatory used for
123 * relocation. This memory can be freed post image load.
124 */
125 void *purgatory_buf;
126 };
127
128 struct kimage;
129
130 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
131 typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
132 unsigned long kernel_len, char *initrd,
133 unsigned long initrd_len, char *cmdline,
134 unsigned long cmdline_len);
135 typedef int (kexec_cleanup_t)(void *loader_data);
136
137 #ifdef CONFIG_KEXEC_SIG
138 typedef int (kexec_verify_sig_t)(const char *kernel_buf,
139 unsigned long kernel_len);
140 #endif
141
142 struct kexec_file_ops {
143 kexec_probe_t *probe;
144 kexec_load_t *load;
145 kexec_cleanup_t *cleanup;
146 #ifdef CONFIG_KEXEC_SIG
147 kexec_verify_sig_t *verify_sig;
148 #endif
149 };
150
151 extern const struct kexec_file_ops * const kexec_file_loaders[];
152
153 int kexec_image_probe_default(struct kimage *image, void *buf,
154 unsigned long buf_len);
155 int kexec_image_post_load_cleanup_default(struct kimage *image);
156
157 /*
158 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole()
159 * will try to allocate free memory. Arch may overwrite it.
160 */
161 #ifndef KEXEC_BUF_MEM_UNKNOWN
162 #define KEXEC_BUF_MEM_UNKNOWN 0
163 #endif
164
165 /**
166 * struct kexec_buf - parameters for finding a place for a buffer in memory
167 * @image: kexec image in which memory to search.
168 * @buffer: Contents which will be copied to the allocated memory.
169 * @bufsz: Size of @buffer.
170 * @mem: On return will have address of the buffer in memory.
171 * @memsz: Size for the buffer in memory.
172 * @buf_align: Minimum alignment needed.
173 * @buf_min: The buffer can't be placed below this address.
174 * @buf_max: The buffer can't be placed above this address.
175 * @top_down: Allocate from top of memory.
176 */
177 struct kexec_buf {
178 struct kimage *image;
179 void *buffer;
180 unsigned long bufsz;
181 unsigned long mem;
182 unsigned long memsz;
183 unsigned long buf_align;
184 unsigned long buf_min;
185 unsigned long buf_max;
186 bool top_down;
187 };
188
189 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
190 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
191 void *buf, unsigned int size,
192 bool get_value);
193 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
194
195 #ifndef arch_kexec_kernel_image_probe
196 static inline int
arch_kexec_kernel_image_probe(struct kimage * image,void * buf,unsigned long buf_len)197 arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len)
198 {
199 return kexec_image_probe_default(image, buf, buf_len);
200 }
201 #endif
202
203 #ifndef arch_kimage_file_post_load_cleanup
arch_kimage_file_post_load_cleanup(struct kimage * image)204 static inline int arch_kimage_file_post_load_cleanup(struct kimage *image)
205 {
206 return kexec_image_post_load_cleanup_default(image);
207 }
208 #endif
209
210 #ifdef CONFIG_KEXEC_SIG
211 #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
212 int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len);
213 #endif
214 #endif
215
216 extern int kexec_add_buffer(struct kexec_buf *kbuf);
217 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
218
219 #ifndef arch_kexec_locate_mem_hole
220 /**
221 * arch_kexec_locate_mem_hole - Find free memory to place the segments.
222 * @kbuf: Parameters for the memory search.
223 *
224 * On success, kbuf->mem will have the start address of the memory region found.
225 *
226 * Return: 0 on success, negative errno on error.
227 */
arch_kexec_locate_mem_hole(struct kexec_buf * kbuf)228 static inline int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
229 {
230 return kexec_locate_mem_hole(kbuf);
231 }
232 #endif
233
234 #ifndef arch_kexec_apply_relocations_add
235 /*
236 * arch_kexec_apply_relocations_add - apply relocations of type RELA
237 * @pi: Purgatory to be relocated.
238 * @section: Section relocations applying to.
239 * @relsec: Section containing RELAs.
240 * @symtab: Corresponding symtab.
241 *
242 * Return: 0 on success, negative errno on error.
243 */
244 static inline int
arch_kexec_apply_relocations_add(struct purgatory_info * pi,Elf_Shdr * section,const Elf_Shdr * relsec,const Elf_Shdr * symtab)245 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
246 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
247 {
248 pr_err("RELA relocation unsupported.\n");
249 return -ENOEXEC;
250 }
251 #endif
252
253 #ifndef arch_kexec_apply_relocations
254 /*
255 * arch_kexec_apply_relocations - apply relocations of type REL
256 * @pi: Purgatory to be relocated.
257 * @section: Section relocations applying to.
258 * @relsec: Section containing RELs.
259 * @symtab: Corresponding symtab.
260 *
261 * Return: 0 on success, negative errno on error.
262 */
263 static inline int
arch_kexec_apply_relocations(struct purgatory_info * pi,Elf_Shdr * section,const Elf_Shdr * relsec,const Elf_Shdr * symtab)264 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
265 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
266 {
267 pr_err("REL relocation unsupported.\n");
268 return -ENOEXEC;
269 }
270 #endif
271 #endif /* CONFIG_KEXEC_FILE */
272
273 #ifdef CONFIG_KEXEC_ELF
274 struct kexec_elf_info {
275 /*
276 * Where the ELF binary contents are kept.
277 * Memory managed by the user of the struct.
278 */
279 const char *buffer;
280
281 const struct elfhdr *ehdr;
282 const struct elf_phdr *proghdrs;
283 };
284
285 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
286 struct kexec_elf_info *elf_info);
287
288 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
289 struct kexec_elf_info *elf_info,
290 struct kexec_buf *kbuf,
291 unsigned long *lowest_load_addr);
292
293 void kexec_free_elf_info(struct kexec_elf_info *elf_info);
294 int kexec_elf_probe(const char *buf, unsigned long len);
295 #endif
296 struct kimage {
297 kimage_entry_t head;
298 kimage_entry_t *entry;
299 kimage_entry_t *last_entry;
300
301 unsigned long start;
302 struct page *control_code_page;
303 struct page *swap_page;
304 void *vmcoreinfo_data_copy; /* locates in the crash memory */
305
306 unsigned long nr_segments;
307 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
308
309 struct list_head control_pages;
310 struct list_head dest_pages;
311 struct list_head unusable_pages;
312
313 /* Address of next control page to allocate for crash kernels. */
314 unsigned long control_page;
315
316 /* Flags to indicate special processing */
317 unsigned int type : 1;
318 #define KEXEC_TYPE_DEFAULT 0
319 #define KEXEC_TYPE_CRASH 1
320 unsigned int preserve_context : 1;
321 /* If set, we are using file mode kexec syscall */
322 unsigned int file_mode:1;
323 #ifdef CONFIG_CRASH_HOTPLUG
324 /* If set, allow changes to elfcorehdr of kexec_load'd image */
325 unsigned int update_elfcorehdr:1;
326 #endif
327
328 #ifdef ARCH_HAS_KIMAGE_ARCH
329 struct kimage_arch arch;
330 #endif
331
332 #ifdef CONFIG_KEXEC_FILE
333 /* Additional fields for file based kexec syscall */
334 void *kernel_buf;
335 unsigned long kernel_buf_len;
336
337 void *initrd_buf;
338 unsigned long initrd_buf_len;
339
340 char *cmdline_buf;
341 unsigned long cmdline_buf_len;
342
343 /* File operations provided by image loader */
344 const struct kexec_file_ops *fops;
345
346 /* Image loader handling the kernel can store a pointer here */
347 void *image_loader_data;
348
349 /* Information for loading purgatory */
350 struct purgatory_info purgatory_info;
351 #endif
352
353 #ifdef CONFIG_CRASH_HOTPLUG
354 int hp_action;
355 int elfcorehdr_index;
356 bool elfcorehdr_updated;
357 #endif
358
359 #ifdef CONFIG_IMA_KEXEC
360 /* Virtual address of IMA measurement buffer for kexec syscall */
361 void *ima_buffer;
362
363 phys_addr_t ima_buffer_addr;
364 size_t ima_buffer_size;
365 #endif
366
367 /* Core ELF header buffer */
368 void *elf_headers;
369 unsigned long elf_headers_sz;
370 unsigned long elf_load_addr;
371 };
372
373 /* kexec interface functions */
374 extern void machine_kexec(struct kimage *image);
375 extern int machine_kexec_prepare(struct kimage *image);
376 extern void machine_kexec_cleanup(struct kimage *image);
377 extern int kernel_kexec(void);
378 extern struct page *kimage_alloc_control_pages(struct kimage *image,
379 unsigned int order);
380
381 #ifndef machine_kexec_post_load
machine_kexec_post_load(struct kimage * image)382 static inline int machine_kexec_post_load(struct kimage *image) { return 0; }
383 #endif
384
385 extern void __crash_kexec(struct pt_regs *);
386 extern void crash_kexec(struct pt_regs *);
387 int kexec_should_crash(struct task_struct *);
388 int kexec_crash_loaded(void);
389 void crash_save_cpu(struct pt_regs *regs, int cpu);
390 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
391
392 extern struct kimage *kexec_image;
393 extern struct kimage *kexec_crash_image;
394
395 bool kexec_load_permitted(int kexec_image_type);
396
397 #ifndef kexec_flush_icache_page
398 #define kexec_flush_icache_page(page)
399 #endif
400
401 /* List of defined/legal kexec flags */
402 #ifndef CONFIG_KEXEC_JUMP
403 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_UPDATE_ELFCOREHDR)
404 #else
405 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT | KEXEC_UPDATE_ELFCOREHDR)
406 #endif
407
408 /* List of defined/legal kexec file flags */
409 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
410 KEXEC_FILE_NO_INITRAMFS)
411
412 /* flag to track if kexec reboot is in progress */
413 extern bool kexec_in_progress;
414
415 int crash_shrink_memory(unsigned long new_size);
416 ssize_t crash_get_memory_size(void);
417
418 #ifndef arch_kexec_protect_crashkres
419 /*
420 * Protection mechanism for crashkernel reserved memory after
421 * the kdump kernel is loaded.
422 *
423 * Provide an empty default implementation here -- architecture
424 * code may override this
425 */
arch_kexec_protect_crashkres(void)426 static inline void arch_kexec_protect_crashkres(void) { }
427 #endif
428
429 #ifndef arch_kexec_unprotect_crashkres
arch_kexec_unprotect_crashkres(void)430 static inline void arch_kexec_unprotect_crashkres(void) { }
431 #endif
432
433 #ifndef page_to_boot_pfn
page_to_boot_pfn(struct page * page)434 static inline unsigned long page_to_boot_pfn(struct page *page)
435 {
436 return page_to_pfn(page);
437 }
438 #endif
439
440 #ifndef boot_pfn_to_page
boot_pfn_to_page(unsigned long boot_pfn)441 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
442 {
443 return pfn_to_page(boot_pfn);
444 }
445 #endif
446
447 #ifndef phys_to_boot_phys
phys_to_boot_phys(phys_addr_t phys)448 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
449 {
450 return phys;
451 }
452 #endif
453
454 #ifndef boot_phys_to_phys
boot_phys_to_phys(unsigned long boot_phys)455 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
456 {
457 return boot_phys;
458 }
459 #endif
460
461 #ifndef crash_free_reserved_phys_range
crash_free_reserved_phys_range(unsigned long begin,unsigned long end)462 static inline void crash_free_reserved_phys_range(unsigned long begin, unsigned long end)
463 {
464 unsigned long addr;
465
466 for (addr = begin; addr < end; addr += PAGE_SIZE)
467 free_reserved_page(boot_pfn_to_page(addr >> PAGE_SHIFT));
468 }
469 #endif
470
virt_to_boot_phys(void * addr)471 static inline unsigned long virt_to_boot_phys(void *addr)
472 {
473 return phys_to_boot_phys(__pa((unsigned long)addr));
474 }
475
boot_phys_to_virt(unsigned long entry)476 static inline void *boot_phys_to_virt(unsigned long entry)
477 {
478 return phys_to_virt(boot_phys_to_phys(entry));
479 }
480
481 #ifndef arch_kexec_post_alloc_pages
arch_kexec_post_alloc_pages(void * vaddr,unsigned int pages,gfp_t gfp)482 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
483 #endif
484
485 #ifndef arch_kexec_pre_free_pages
arch_kexec_pre_free_pages(void * vaddr,unsigned int pages)486 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
487 #endif
488
489 #ifndef arch_crash_handle_hotplug_event
arch_crash_handle_hotplug_event(struct kimage * image)490 static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
491 #endif
492
493 int crash_check_update_elfcorehdr(void);
494
495 #ifndef crash_hotplug_cpu_support
crash_hotplug_cpu_support(void)496 static inline int crash_hotplug_cpu_support(void) { return 0; }
497 #endif
498
499 #ifndef crash_hotplug_memory_support
crash_hotplug_memory_support(void)500 static inline int crash_hotplug_memory_support(void) { return 0; }
501 #endif
502
503 #ifndef crash_get_elfcorehdr_size
crash_get_elfcorehdr_size(void)504 static inline unsigned int crash_get_elfcorehdr_size(void) { return 0; }
505 #endif
506
507 #else /* !CONFIG_KEXEC_CORE */
508 struct pt_regs;
509 struct task_struct;
__crash_kexec(struct pt_regs * regs)510 static inline void __crash_kexec(struct pt_regs *regs) { }
crash_kexec(struct pt_regs * regs)511 static inline void crash_kexec(struct pt_regs *regs) { }
kexec_should_crash(struct task_struct * p)512 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
kexec_crash_loaded(void)513 static inline int kexec_crash_loaded(void) { return 0; }
514 #define kexec_in_progress false
515 #endif /* CONFIG_KEXEC_CORE */
516
517 #ifdef CONFIG_KEXEC_SIG
518 void set_kexec_sig_enforced(void);
519 #else
set_kexec_sig_enforced(void)520 static inline void set_kexec_sig_enforced(void) {}
521 #endif
522
523 #endif /* !defined(__ASSEBMLY__) */
524
525 #endif /* LINUX_KEXEC_H */
526