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