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);
146int kexec_image_post_load_cleanup_default(struct kimage *image);
147
148/*
149 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole()
150 * will try to allocate free memory. Arch may overwrite it.
151 */
152#ifndef KEXEC_BUF_MEM_UNKNOWN
153#define KEXEC_BUF_MEM_UNKNOWN 0
154#endif
155
156/**
157 * struct kexec_buf - parameters for finding a place for a buffer in memory
158 * @image: kexec image in which memory to search.
159 * @buffer: Contents which will be copied to the allocated memory.
160 * @bufsz: Size of @buffer.
161 * @mem: On return will have address of the buffer in memory.
162 * @memsz: Size for the buffer in memory.
163 * @buf_align: Minimum alignment needed.
164 * @buf_min: The buffer can't be placed below this address.
165 * @buf_max: The buffer can't be placed above this address.
166 * @top_down: Allocate from top of memory.
167 */
168struct kexec_buf {
169 struct kimage *image;
170 void *buffer;
171 unsigned long bufsz;
172 unsigned long mem;
173 unsigned long memsz;
174 unsigned long buf_align;
175 unsigned long buf_min;
176 unsigned long buf_max;
177 bool top_down;
178};
179
180int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
181int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
182 void *buf, unsigned int size,
183 bool get_value);
184void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
185
186void * __weak arch_kexec_kernel_image_load(struct kimage *image);
187int __weak arch_kexec_apply_relocations_add(struct purgatory_info *pi,
188 Elf_Shdr *section,
189 const Elf_Shdr *relsec,
190 const Elf_Shdr *symtab);
191int __weak arch_kexec_apply_relocations(struct purgatory_info *pi,
192 Elf_Shdr *section,
193 const Elf_Shdr *relsec,
194 const Elf_Shdr *symtab);
195
196extern int kexec_add_buffer(struct kexec_buf *kbuf);
197int kexec_locate_mem_hole(struct kexec_buf *kbuf);
198
199/* Alignment required for elf header segment */
200#define ELF_CORE_HEADER_ALIGN 4096
201
202struct crash_mem_range {
203 u64 start, end;
204};
205
206struct crash_mem {
207 unsigned int max_nr_ranges;
208 unsigned int nr_ranges;
209 struct crash_mem_range ranges[0];
210};
211
212extern int crash_exclude_mem_range(struct crash_mem *mem,
213 unsigned long long mstart,
214 unsigned long long mend);
215extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
216 void **addr, unsigned long *sz);
217#endif /* CONFIG_KEXEC_FILE */
218
219struct kimage {
220 kimage_entry_t head;
221 kimage_entry_t *entry;
222 kimage_entry_t *last_entry;
223
224 unsigned long start;
225 struct page *control_code_page;
226 struct page *swap_page;
227 void *vmcoreinfo_data_copy; /* locates in the crash memory */
228
229 unsigned long nr_segments;
230 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
231
232 struct list_head control_pages;
233 struct list_head dest_pages;
234 struct list_head unusable_pages;
235
236 /* Address of next control page to allocate for crash kernels. */
237 unsigned long control_page;
238
239 /* Flags to indicate special processing */
240 unsigned int type : 1;
241#define KEXEC_TYPE_DEFAULT 0
242#define KEXEC_TYPE_CRASH 1
243 unsigned int preserve_context : 1;
244 /* If set, we are using file mode kexec syscall */
245 unsigned int file_mode:1;
246
247#ifdef ARCH_HAS_KIMAGE_ARCH
248 struct kimage_arch arch;
249#endif
250
251#ifdef CONFIG_KEXEC_FILE
252 /* Additional fields for file based kexec syscall */
253 void *kernel_buf;
254 unsigned long kernel_buf_len;
255
256 void *initrd_buf;
257 unsigned long initrd_buf_len;
258
259 char *cmdline_buf;
260 unsigned long cmdline_buf_len;
261
262 /* File operations provided by image loader */
263 const struct kexec_file_ops *fops;
264
265 /* Image loader handling the kernel can store a pointer here */
266 void *image_loader_data;
267
268 /* Information for loading purgatory */
269 struct purgatory_info purgatory_info;
270#endif
271};
272
273/* kexec interface functions */
274extern void machine_kexec(struct kimage *image);
275extern int machine_kexec_prepare(struct kimage *image);
276extern void machine_kexec_cleanup(struct kimage *image);
277extern int kernel_kexec(void);
278extern struct page *kimage_alloc_control_pages(struct kimage *image,
279 unsigned int order);
280extern void __crash_kexec(struct pt_regs *);
281extern void crash_kexec(struct pt_regs *);
282int kexec_should_crash(struct task_struct *);
283int kexec_crash_loaded(void);
284void crash_save_cpu(struct pt_regs *regs, int cpu);
285extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
286
287extern struct kimage *kexec_image;
288extern struct kimage *kexec_crash_image;
289extern int kexec_load_disabled;
290
291#ifndef kexec_flush_icache_page
292#define kexec_flush_icache_page(page)
293#endif
294
295/* List of defined/legal kexec flags */
296#ifndef CONFIG_KEXEC_JUMP
297#define KEXEC_FLAGS KEXEC_ON_CRASH
298#else
299#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
300#endif
301
302/* List of defined/legal kexec file flags */
303#define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
304 KEXEC_FILE_NO_INITRAMFS)
305
306/* Location of a reserved region to hold the crash kernel.
307 */
308extern struct resource crashk_res;
309extern struct resource crashk_low_res;
310extern note_buf_t __percpu *crash_notes;
311
312/* flag to track if kexec reboot is in progress */
313extern bool kexec_in_progress;
314
315int crash_shrink_memory(unsigned long new_size);
316size_t crash_get_memory_size(void);
317void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
318
319void arch_kexec_protect_crashkres(void);
320void arch_kexec_unprotect_crashkres(void);
321
322#ifndef page_to_boot_pfn
323static inline unsigned long page_to_boot_pfn(struct page *page)
324{
325 return page_to_pfn(page);
326}
327#endif
328
329#ifndef boot_pfn_to_page
330static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
331{
332 return pfn_to_page(boot_pfn);
333}
334#endif
335
336#ifndef phys_to_boot_phys
337static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
338{
339 return phys;
340}
341#endif
342
343#ifndef boot_phys_to_phys
344static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
345{
346 return boot_phys;
347}
348#endif
349
350static inline unsigned long virt_to_boot_phys(void *addr)
351{
352 return phys_to_boot_phys(__pa((unsigned long)addr));
353}
354
355static inline void *boot_phys_to_virt(unsigned long entry)
356{
357 return phys_to_virt(boot_phys_to_phys(entry));
358}
359
360#ifndef arch_kexec_post_alloc_pages
361static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
362#endif
363
364#ifndef arch_kexec_pre_free_pages
365static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
366#endif
367
368#else /* !CONFIG_KEXEC_CORE */
369struct pt_regs;
370struct task_struct;
371static inline void __crash_kexec(struct pt_regs *regs) { }
372static inline void crash_kexec(struct pt_regs *regs) { }
373static inline int kexec_should_crash(struct task_struct *p) { return 0; }
374static inline int kexec_crash_loaded(void) { return 0; }
375#define kexec_in_progress false
376#endif /* CONFIG_KEXEC_CORE */
377
378#endif /* !defined(__ASSEBMLY__) */
379
380#endif /* LINUX_KEXEC_H */
381