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
21#include <uapi/linux/kexec.h>
22
23/* Location of a reserved region to hold the crash kernel.
24 */
25extern struct resource crashk_res;
26extern struct resource crashk_low_res;
27extern note_buf_t __percpu *crash_notes;
28
29#ifdef CONFIG_KEXEC_CORE
30#include <linux/list.h>
31#include <linux/compat.h>
32#include <linux/ioport.h>
33#include <linux/module.h>
34#include <asm/kexec.h>
35
36/* Verify architecture specific macros are defined */
37
38#ifndef KEXEC_SOURCE_MEMORY_LIMIT
39#error KEXEC_SOURCE_MEMORY_LIMIT not defined
40#endif
41
42#ifndef KEXEC_DESTINATION_MEMORY_LIMIT
43#error KEXEC_DESTINATION_MEMORY_LIMIT not defined
44#endif
45
46#ifndef KEXEC_CONTROL_MEMORY_LIMIT
47#error KEXEC_CONTROL_MEMORY_LIMIT not defined
48#endif
49
50#ifndef KEXEC_CONTROL_MEMORY_GFP
51#define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
52#endif
53
54#ifndef KEXEC_CONTROL_PAGE_SIZE
55#error KEXEC_CONTROL_PAGE_SIZE not defined
56#endif
57
58#ifndef KEXEC_ARCH
59#error KEXEC_ARCH not defined
60#endif
61
62#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
63#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
64#endif
65
66#ifndef KEXEC_CRASH_MEM_ALIGN
67#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
68#endif
69
70#define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME
71
72/*
73 * This structure is used to hold the arguments that are used when loading
74 * kernel binaries.
75 */
76
77typedef unsigned long kimage_entry_t;
78
79struct kexec_segment {
80 /*
81 * This pointer can point to user memory if kexec_load() system
82 * call is used or will point to kernel memory if
83 * kexec_file_load() system call is used.
84 *
85 * Use ->buf when expecting to deal with user memory and use ->kbuf
86 * when expecting to deal with kernel memory.
87 */
88 union {
89 void __user *buf;
90 void *kbuf;
91 };
92 size_t bufsz;
93 unsigned long mem;
94 size_t memsz;
95};
96
97#ifdef CONFIG_COMPAT
98struct compat_kexec_segment {
99 compat_uptr_t buf;
100 compat_size_t bufsz;
101 compat_ulong_t mem; /* User space sees this as a (void *) ... */
102 compat_size_t memsz;
103};
104#endif
105
106#ifdef CONFIG_KEXEC_FILE
107struct purgatory_info {
108 /*
109 * Pointer to elf header at the beginning of kexec_purgatory.
110 * Note: kexec_purgatory is read only
111 */
112 const Elf_Ehdr *ehdr;
113 /*
114 * Temporary, modifiable buffer for sechdrs used for relocation.
115 * This memory can be freed post image load.
116 */
117 Elf_Shdr *sechdrs;
118 /*
119 * Temporary, modifiable buffer for stripped purgatory used for
120 * relocation. This memory can be freed post image load.
121 */
122 void *purgatory_buf;
123};
124
125struct kimage;
126
127typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
128typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
129 unsigned long kernel_len, char *initrd,
130 unsigned long initrd_len, char *cmdline,
131 unsigned long cmdline_len);
132typedef int (kexec_cleanup_t)(void *loader_data);
133
134#ifdef CONFIG_KEXEC_SIG
135typedef int (kexec_verify_sig_t)(const char *kernel_buf,
136 unsigned long kernel_len);
137#endif
138
139struct kexec_file_ops {
140 kexec_probe_t *probe;
141 kexec_load_t *load;
142 kexec_cleanup_t *cleanup;
143#ifdef CONFIG_KEXEC_SIG
144 kexec_verify_sig_t *verify_sig;
145#endif
146};
147
148extern const struct kexec_file_ops * const kexec_file_loaders[];
149
150int kexec_image_probe_default(struct kimage *image, void *buf,
151 unsigned long buf_len);
152int kexec_image_post_load_cleanup_default(struct kimage *image);
153
154/*
155 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole()
156 * will try to allocate free memory. Arch may overwrite it.
157 */
158#ifndef KEXEC_BUF_MEM_UNKNOWN
159#define KEXEC_BUF_MEM_UNKNOWN 0
160#endif
161
162/**
163 * struct kexec_buf - parameters for finding a place for a buffer in memory
164 * @image: kexec image in which memory to search.
165 * @buffer: Contents which will be copied to the allocated memory.
166 * @bufsz: Size of @buffer.
167 * @mem: On return will have address of the buffer in memory.
168 * @memsz: Size for the buffer in memory.
169 * @buf_align: Minimum alignment needed.
170 * @buf_min: The buffer can't be placed below this address.
171 * @buf_max: The buffer can't be placed above this address.
172 * @top_down: Allocate from top of memory.
173 */
174struct kexec_buf {
175 struct kimage *image;
176 void *buffer;
177 unsigned long bufsz;
178 unsigned long mem;
179 unsigned long memsz;
180 unsigned long buf_align;
181 unsigned long buf_min;
182 unsigned long buf_max;
183 bool top_down;
184};
185
186int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
187int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
188 void *buf, unsigned int size,
189 bool get_value);
190void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
191
192/* Architectures may override the below functions */
193int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
194 unsigned long buf_len);
195void *arch_kexec_kernel_image_load(struct kimage *image);
196int arch_kimage_file_post_load_cleanup(struct kimage *image);
197#ifdef CONFIG_KEXEC_SIG
198int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
199 unsigned long buf_len);
200#endif
201int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
202
203extern int kexec_add_buffer(struct kexec_buf *kbuf);
204int kexec_locate_mem_hole(struct kexec_buf *kbuf);
205
206/* Alignment required for elf header segment */
207#define ELF_CORE_HEADER_ALIGN 4096
208
209struct crash_mem_range {
210 u64 start, end;
211};
212
213struct crash_mem {
214 unsigned int max_nr_ranges;
215 unsigned int nr_ranges;
216 struct crash_mem_range ranges[];
217};
218
219extern int crash_exclude_mem_range(struct crash_mem *mem,
220 unsigned long long mstart,
221 unsigned long long mend);
222extern int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
223 void **addr, unsigned long *sz);
224
225#ifndef arch_kexec_apply_relocations_add
226/*
227 * arch_kexec_apply_relocations_add - apply relocations of type RELA
228 * @pi: Purgatory to be relocated.
229 * @section: Section relocations applying to.
230 * @relsec: Section containing RELAs.
231 * @symtab: Corresponding symtab.
232 *
233 * Return: 0 on success, negative errno on error.
234 */
235static inline int
236arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
237 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
238{
239 pr_err("RELA relocation unsupported.\n");
240 return -ENOEXEC;
241}
242#endif
243
244#ifndef arch_kexec_apply_relocations
245/*
246 * arch_kexec_apply_relocations - apply relocations of type REL
247 * @pi: Purgatory to be relocated.
248 * @section: Section relocations applying to.
249 * @relsec: Section containing RELs.
250 * @symtab: Corresponding symtab.
251 *
252 * Return: 0 on success, negative errno on error.
253 */
254static inline int
255arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
256 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
257{
258 pr_err("REL relocation unsupported.\n");
259 return -ENOEXEC;
260}
261#endif
262#endif /* CONFIG_KEXEC_FILE */
263
264#ifdef CONFIG_KEXEC_ELF
265struct kexec_elf_info {
266 /*
267 * Where the ELF binary contents are kept.
268 * Memory managed by the user of the struct.
269 */
270 const char *buffer;
271
272 const struct elfhdr *ehdr;
273 const struct elf_phdr *proghdrs;
274};
275
276int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
277 struct kexec_elf_info *elf_info);
278
279int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
280 struct kexec_elf_info *elf_info,
281 struct kexec_buf *kbuf,
282 unsigned long *lowest_load_addr);
283
284void kexec_free_elf_info(struct kexec_elf_info *elf_info);
285int kexec_elf_probe(const char *buf, unsigned long len);
286#endif
287struct kimage {
288 kimage_entry_t head;
289 kimage_entry_t *entry;
290 kimage_entry_t *last_entry;
291
292 unsigned long start;
293 struct page *control_code_page;
294 struct page *swap_page;
295 void *vmcoreinfo_data_copy; /* locates in the crash memory */
296
297 unsigned long nr_segments;
298 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
299
300 struct list_head control_pages;
301 struct list_head dest_pages;
302 struct list_head unusable_pages;
303
304 /* Address of next control page to allocate for crash kernels. */
305 unsigned long control_page;
306
307 /* Flags to indicate special processing */
308 unsigned int type : 1;
309#define KEXEC_TYPE_DEFAULT 0
310#define KEXEC_TYPE_CRASH 1
311 unsigned int preserve_context : 1;
312 /* If set, we are using file mode kexec syscall */
313 unsigned int file_mode:1;
314
315#ifdef ARCH_HAS_KIMAGE_ARCH
316 struct kimage_arch arch;
317#endif
318
319#ifdef CONFIG_KEXEC_FILE
320 /* Additional fields for file based kexec syscall */
321 void *kernel_buf;
322 unsigned long kernel_buf_len;
323
324 void *initrd_buf;
325 unsigned long initrd_buf_len;
326
327 char *cmdline_buf;
328 unsigned long cmdline_buf_len;
329
330 /* File operations provided by image loader */
331 const struct kexec_file_ops *fops;
332
333 /* Image loader handling the kernel can store a pointer here */
334 void *image_loader_data;
335
336 /* Information for loading purgatory */
337 struct purgatory_info purgatory_info;
338#endif
339
340#ifdef CONFIG_IMA_KEXEC
341 /* Virtual address of IMA measurement buffer for kexec syscall */
342 void *ima_buffer;
343
344 phys_addr_t ima_buffer_addr;
345 size_t ima_buffer_size;
346#endif
347
348 /* Core ELF header buffer */
349 void *elf_headers;
350 unsigned long elf_headers_sz;
351 unsigned long elf_load_addr;
352};
353
354/* kexec interface functions */
355extern void machine_kexec(struct kimage *image);
356extern int machine_kexec_prepare(struct kimage *image);
357extern void machine_kexec_cleanup(struct kimage *image);
358extern int kernel_kexec(void);
359extern struct page *kimage_alloc_control_pages(struct kimage *image,
360 unsigned int order);
361int machine_kexec_post_load(struct kimage *image);
362
363extern void __crash_kexec(struct pt_regs *);
364extern void crash_kexec(struct pt_regs *);
365int kexec_should_crash(struct task_struct *);
366int kexec_crash_loaded(void);
367void crash_save_cpu(struct pt_regs *regs, int cpu);
368extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
369
370extern struct kimage *kexec_image;
371extern struct kimage *kexec_crash_image;
372extern int kexec_load_disabled;
373
374#ifndef kexec_flush_icache_page
375#define kexec_flush_icache_page(page)
376#endif
377
378/* List of defined/legal kexec flags */
379#ifndef CONFIG_KEXEC_JUMP
380#define KEXEC_FLAGS KEXEC_ON_CRASH
381#else
382#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
383#endif
384
385/* List of defined/legal kexec file flags */
386#define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
387 KEXEC_FILE_NO_INITRAMFS)
388
389/* flag to track if kexec reboot is in progress */
390extern bool kexec_in_progress;
391
392int crash_shrink_memory(unsigned long new_size);
393size_t crash_get_memory_size(void);
394void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
395
396void arch_kexec_protect_crashkres(void);
397void arch_kexec_unprotect_crashkres(void);
398
399#ifndef page_to_boot_pfn
400static 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
407static 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
414static 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
421static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
422{
423 return boot_phys;
424}
425#endif
426
427static inline unsigned long virt_to_boot_phys(void *addr)
428{
429 return phys_to_boot_phys(__pa((unsigned long)addr));
430}
431
432static 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
438static 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
442static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
443#endif
444
445#else /* !CONFIG_KEXEC_CORE */
446struct pt_regs;
447struct task_struct;
448static inline void __crash_kexec(struct pt_regs *regs) { }
449static inline void crash_kexec(struct pt_regs *regs) { }
450static inline int kexec_should_crash(struct task_struct *p) { return 0; }
451static 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
456void set_kexec_sig_enforced(void);
457#else
458static inline void set_kexec_sig_enforced(void) {}
459#endif
460
461#endif /* !defined(__ASSEBMLY__) */
462
463#endif /* LINUX_KEXEC_H */