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