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_kexec_apply_relocations_add(struct purgatory_info *pi,
197 Elf_Shdr *section,
198 const Elf_Shdr *relsec,
199 const Elf_Shdr *symtab);
200int arch_kexec_apply_relocations(struct purgatory_info *pi,
201 Elf_Shdr *section,
202 const Elf_Shdr *relsec,
203 const Elf_Shdr *symtab);
204int arch_kimage_file_post_load_cleanup(struct kimage *image);
205#ifdef CONFIG_KEXEC_SIG
206int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
207 unsigned long buf_len);
208#endif
209int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
210
211extern int kexec_add_buffer(struct kexec_buf *kbuf);
212int kexec_locate_mem_hole(struct kexec_buf *kbuf);
213
214/* Alignment required for elf header segment */
215#define ELF_CORE_HEADER_ALIGN 4096
216
217struct crash_mem_range {
218 u64 start, end;
219};
220
221struct crash_mem {
222 unsigned int max_nr_ranges;
223 unsigned int nr_ranges;
224 struct crash_mem_range ranges[];
225};
226
227extern int crash_exclude_mem_range(struct crash_mem *mem,
228 unsigned long long mstart,
229 unsigned long long mend);
230extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
231 void **addr, unsigned long *sz);
232#endif /* CONFIG_KEXEC_FILE */
233
234#ifdef CONFIG_KEXEC_ELF
235struct kexec_elf_info {
236 /*
237 * Where the ELF binary contents are kept.
238 * Memory managed by the user of the struct.
239 */
240 const char *buffer;
241
242 const struct elfhdr *ehdr;
243 const struct elf_phdr *proghdrs;
244};
245
246int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
247 struct kexec_elf_info *elf_info);
248
249int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
250 struct kexec_elf_info *elf_info,
251 struct kexec_buf *kbuf,
252 unsigned long *lowest_load_addr);
253
254void kexec_free_elf_info(struct kexec_elf_info *elf_info);
255int kexec_elf_probe(const char *buf, unsigned long len);
256#endif
257struct kimage {
258 kimage_entry_t head;
259 kimage_entry_t *entry;
260 kimage_entry_t *last_entry;
261
262 unsigned long start;
263 struct page *control_code_page;
264 struct page *swap_page;
265 void *vmcoreinfo_data_copy; /* locates in the crash memory */
266
267 unsigned long nr_segments;
268 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
269
270 struct list_head control_pages;
271 struct list_head dest_pages;
272 struct list_head unusable_pages;
273
274 /* Address of next control page to allocate for crash kernels. */
275 unsigned long control_page;
276
277 /* Flags to indicate special processing */
278 unsigned int type : 1;
279#define KEXEC_TYPE_DEFAULT 0
280#define KEXEC_TYPE_CRASH 1
281 unsigned int preserve_context : 1;
282 /* If set, we are using file mode kexec syscall */
283 unsigned int file_mode:1;
284
285#ifdef ARCH_HAS_KIMAGE_ARCH
286 struct kimage_arch arch;
287#endif
288
289#ifdef CONFIG_KEXEC_FILE
290 /* Additional fields for file based kexec syscall */
291 void *kernel_buf;
292 unsigned long kernel_buf_len;
293
294 void *initrd_buf;
295 unsigned long initrd_buf_len;
296
297 char *cmdline_buf;
298 unsigned long cmdline_buf_len;
299
300 /* File operations provided by image loader */
301 const struct kexec_file_ops *fops;
302
303 /* Image loader handling the kernel can store a pointer here */
304 void *image_loader_data;
305
306 /* Information for loading purgatory */
307 struct purgatory_info purgatory_info;
308#endif
309
310#ifdef CONFIG_IMA_KEXEC
311 /* Virtual address of IMA measurement buffer for kexec syscall */
312 void *ima_buffer;
313
314 phys_addr_t ima_buffer_addr;
315 size_t ima_buffer_size;
316#endif
317
318 /* Core ELF header buffer */
319 void *elf_headers;
320 unsigned long elf_headers_sz;
321 unsigned long elf_load_addr;
322};
323
324/* kexec interface functions */
325extern void machine_kexec(struct kimage *image);
326extern int machine_kexec_prepare(struct kimage *image);
327extern void machine_kexec_cleanup(struct kimage *image);
328extern int kernel_kexec(void);
329extern struct page *kimage_alloc_control_pages(struct kimage *image,
330 unsigned int order);
331int machine_kexec_post_load(struct kimage *image);
332
333extern void __crash_kexec(struct pt_regs *);
334extern void crash_kexec(struct pt_regs *);
335int kexec_should_crash(struct task_struct *);
336int kexec_crash_loaded(void);
337void crash_save_cpu(struct pt_regs *regs, int cpu);
338extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
339
340extern struct kimage *kexec_image;
341extern struct kimage *kexec_crash_image;
342extern int kexec_load_disabled;
343
344#ifndef kexec_flush_icache_page
345#define kexec_flush_icache_page(page)
346#endif
347
348/* List of defined/legal kexec flags */
349#ifndef CONFIG_KEXEC_JUMP
350#define KEXEC_FLAGS KEXEC_ON_CRASH
351#else
352#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
353#endif
354
355/* List of defined/legal kexec file flags */
356#define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
357 KEXEC_FILE_NO_INITRAMFS)
358
359/* flag to track if kexec reboot is in progress */
360extern bool kexec_in_progress;
361
362int crash_shrink_memory(unsigned long new_size);
363size_t crash_get_memory_size(void);
364void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
365
366void arch_kexec_protect_crashkres(void);
367void arch_kexec_unprotect_crashkres(void);
368
369#ifndef page_to_boot_pfn
370static inline unsigned long page_to_boot_pfn(struct page *page)
371{
372 return page_to_pfn(page);
373}
374#endif
375
376#ifndef boot_pfn_to_page
377static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
378{
379 return pfn_to_page(boot_pfn);
380}
381#endif
382
383#ifndef phys_to_boot_phys
384static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
385{
386 return phys;
387}
388#endif
389
390#ifndef boot_phys_to_phys
391static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
392{
393 return boot_phys;
394}
395#endif
396
397static inline unsigned long virt_to_boot_phys(void *addr)
398{
399 return phys_to_boot_phys(__pa((unsigned long)addr));
400}
401
402static inline void *boot_phys_to_virt(unsigned long entry)
403{
404 return phys_to_virt(boot_phys_to_phys(entry));
405}
406
407#ifndef arch_kexec_post_alloc_pages
408static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
409#endif
410
411#ifndef arch_kexec_pre_free_pages
412static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
413#endif
414
415#else /* !CONFIG_KEXEC_CORE */
416struct pt_regs;
417struct task_struct;
418static inline void __crash_kexec(struct pt_regs *regs) { }
419static inline void crash_kexec(struct pt_regs *regs) { }
420static inline int kexec_should_crash(struct task_struct *p) { return 0; }
421static inline int kexec_crash_loaded(void) { return 0; }
422#define kexec_in_progress false
423#endif /* CONFIG_KEXEC_CORE */
424
425#endif /* !defined(__ASSEBMLY__) */
426
427#endif /* LINUX_KEXEC_H */