Linux kernel mirror (for testing)
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linux
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 */
27extern struct resource crashk_res;
28extern struct resource crashk_low_res;
29extern 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
80typedef unsigned long kimage_entry_t;
81
82struct 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
101struct 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
110struct 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
128struct kimage;
129
130typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
131typedef 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);
135typedef int (kexec_cleanup_t)(void *loader_data);
136
137#ifdef CONFIG_KEXEC_SIG
138typedef int (kexec_verify_sig_t)(const char *kernel_buf,
139 unsigned long kernel_len);
140#endif
141
142struct 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
151extern const struct kexec_file_ops * const kexec_file_loaders[];
152
153int kexec_image_probe_default(struct kimage *image, void *buf,
154 unsigned long buf_len);
155int 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 */
177struct 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
189int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
190int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
191 void *buf, unsigned int size,
192 bool get_value);
193void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
194
195#ifndef arch_kexec_kernel_image_probe
196static inline int
197arch_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
204static 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
212int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len);
213#endif
214#endif
215
216extern int kexec_add_buffer(struct kexec_buf *kbuf);
217int 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 */
228static 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 */
244static inline int
245arch_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 */
263static inline int
264arch_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
274struct 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
285int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
286 struct kexec_elf_info *elf_info);
287
288int 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
293void kexec_free_elf_info(struct kexec_elf_info *elf_info);
294int kexec_elf_probe(const char *buf, unsigned long len);
295#endif
296struct 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 */
374extern void machine_kexec(struct kimage *image);
375extern int machine_kexec_prepare(struct kimage *image);
376extern void machine_kexec_cleanup(struct kimage *image);
377extern int kernel_kexec(void);
378extern struct page *kimage_alloc_control_pages(struct kimage *image,
379 unsigned int order);
380
381#ifndef machine_kexec_post_load
382static inline int machine_kexec_post_load(struct kimage *image) { return 0; }
383#endif
384
385extern void __crash_kexec(struct pt_regs *);
386extern void crash_kexec(struct pt_regs *);
387int kexec_should_crash(struct task_struct *);
388int kexec_crash_loaded(void);
389void crash_save_cpu(struct pt_regs *regs, int cpu);
390extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
391
392extern struct kimage *kexec_image;
393extern struct kimage *kexec_crash_image;
394
395bool 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 */
413extern bool kexec_in_progress;
414
415int crash_shrink_memory(unsigned long new_size);
416ssize_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 */
426static inline void arch_kexec_protect_crashkres(void) { }
427#endif
428
429#ifndef arch_kexec_unprotect_crashkres
430static inline void arch_kexec_unprotect_crashkres(void) { }
431#endif
432
433#ifndef page_to_boot_pfn
434static 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
441static 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
448static 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
455static 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
462static 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
471static inline unsigned long virt_to_boot_phys(void *addr)
472{
473 return phys_to_boot_phys(__pa((unsigned long)addr));
474}
475
476static 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
482static 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
486static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
487#endif
488
489#ifndef arch_crash_handle_hotplug_event
490static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
491#endif
492
493int crash_check_update_elfcorehdr(void);
494
495#ifndef crash_hotplug_cpu_support
496static inline int crash_hotplug_cpu_support(void) { return 0; }
497#endif
498
499#ifndef crash_hotplug_memory_support
500static inline int crash_hotplug_memory_support(void) { return 0; }
501#endif
502
503#ifndef crash_get_elfcorehdr_size
504static inline unsigned int crash_get_elfcorehdr_size(void) { return 0; }
505#endif
506
507#else /* !CONFIG_KEXEC_CORE */
508struct pt_regs;
509struct task_struct;
510static inline void __crash_kexec(struct pt_regs *regs) { }
511static inline void crash_kexec(struct pt_regs *regs) { }
512static inline int kexec_should_crash(struct task_struct *p) { return 0; }
513static 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
518void set_kexec_sig_enforced(void);
519#else
520static inline void set_kexec_sig_enforced(void) {}
521#endif
522
523#endif /* !defined(__ASSEBMLY__) */
524
525#endif /* LINUX_KEXEC_H */