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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 
71 typedef unsigned long kimage_entry_t;
72 
73 struct 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
92 struct 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
101 struct 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 
119 struct kimage;
120 
121 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
122 typedef 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);
126 typedef int (kexec_cleanup_t)(void *loader_data);
127 
128 #ifdef CONFIG_KEXEC_SIG
129 typedef int (kexec_verify_sig_t)(const char *kernel_buf,
130 				 unsigned long kernel_len);
131 #endif
132 
133 struct kexec_file_ops {
134 	kexec_probe_t *probe;
135 	kexec_load_t *load;
136 	kexec_cleanup_t *cleanup;
137 #ifdef CONFIG_KEXEC_SIG
138 	kexec_verify_sig_t *verify_sig;
139 #endif
140 };
141 
142 extern const struct kexec_file_ops * const kexec_file_loaders[];
143 
144 int kexec_image_probe_default(struct kimage *image, void *buf,
145 			      unsigned long buf_len);
146 int 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  */
168 struct 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 
180 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
181 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
182 				   void *buf, unsigned int size,
183 				   bool get_value);
184 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
185 
186 /* Architectures may override the below functions */
187 int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
188 				  unsigned long buf_len);
189 void *arch_kexec_kernel_image_load(struct kimage *image);
190 int arch_kexec_apply_relocations_add(struct purgatory_info *pi,
191 				     Elf_Shdr *section,
192 				     const Elf_Shdr *relsec,
193 				     const Elf_Shdr *symtab);
194 int arch_kexec_apply_relocations(struct purgatory_info *pi,
195 				 Elf_Shdr *section,
196 				 const Elf_Shdr *relsec,
197 				 const Elf_Shdr *symtab);
198 int arch_kimage_file_post_load_cleanup(struct kimage *image);
199 #ifdef CONFIG_KEXEC_SIG
200 int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
201 				 unsigned long buf_len);
202 #endif
203 int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf);
204 
205 extern int kexec_add_buffer(struct kexec_buf *kbuf);
206 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
207 
208 /* Alignment required for elf header segment */
209 #define ELF_CORE_HEADER_ALIGN   4096
210 
211 struct crash_mem_range {
212 	u64 start, end;
213 };
214 
215 struct crash_mem {
216 	unsigned int max_nr_ranges;
217 	unsigned int nr_ranges;
218 	struct crash_mem_range ranges[];
219 };
220 
221 extern int crash_exclude_mem_range(struct crash_mem *mem,
222 				   unsigned long long mstart,
223 				   unsigned long long mend);
224 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map,
225 				       void **addr, unsigned long *sz);
226 #endif /* CONFIG_KEXEC_FILE */
227 
228 #ifdef CONFIG_KEXEC_ELF
229 struct kexec_elf_info {
230 	/*
231 	 * Where the ELF binary contents are kept.
232 	 * Memory managed by the user of the struct.
233 	 */
234 	const char *buffer;
235 
236 	const struct elfhdr *ehdr;
237 	const struct elf_phdr *proghdrs;
238 };
239 
240 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
241 			       struct kexec_elf_info *elf_info);
242 
243 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
244 			 struct kexec_elf_info *elf_info,
245 			 struct kexec_buf *kbuf,
246 			 unsigned long *lowest_load_addr);
247 
248 void kexec_free_elf_info(struct kexec_elf_info *elf_info);
249 int kexec_elf_probe(const char *buf, unsigned long len);
250 #endif
251 struct kimage {
252 	kimage_entry_t head;
253 	kimage_entry_t *entry;
254 	kimage_entry_t *last_entry;
255 
256 	unsigned long start;
257 	struct page *control_code_page;
258 	struct page *swap_page;
259 	void *vmcoreinfo_data_copy; /* locates in the crash memory */
260 
261 	unsigned long nr_segments;
262 	struct kexec_segment segment[KEXEC_SEGMENT_MAX];
263 
264 	struct list_head control_pages;
265 	struct list_head dest_pages;
266 	struct list_head unusable_pages;
267 
268 	/* Address of next control page to allocate for crash kernels. */
269 	unsigned long control_page;
270 
271 	/* Flags to indicate special processing */
272 	unsigned int type : 1;
273 #define KEXEC_TYPE_DEFAULT 0
274 #define KEXEC_TYPE_CRASH   1
275 	unsigned int preserve_context : 1;
276 	/* If set, we are using file mode kexec syscall */
277 	unsigned int file_mode:1;
278 
279 #ifdef ARCH_HAS_KIMAGE_ARCH
280 	struct kimage_arch arch;
281 #endif
282 
283 #ifdef CONFIG_KEXEC_FILE
284 	/* Additional fields for file based kexec syscall */
285 	void *kernel_buf;
286 	unsigned long kernel_buf_len;
287 
288 	void *initrd_buf;
289 	unsigned long initrd_buf_len;
290 
291 	char *cmdline_buf;
292 	unsigned long cmdline_buf_len;
293 
294 	/* File operations provided by image loader */
295 	const struct kexec_file_ops *fops;
296 
297 	/* Image loader handling the kernel can store a pointer here */
298 	void *image_loader_data;
299 
300 	/* Information for loading purgatory */
301 	struct purgatory_info purgatory_info;
302 #endif
303 
304 #ifdef CONFIG_IMA_KEXEC
305 	/* Virtual address of IMA measurement buffer for kexec syscall */
306 	void *ima_buffer;
307 #endif
308 };
309 
310 /* kexec interface functions */
311 extern void machine_kexec(struct kimage *image);
312 extern int machine_kexec_prepare(struct kimage *image);
313 extern void machine_kexec_cleanup(struct kimage *image);
314 extern int kernel_kexec(void);
315 extern struct page *kimage_alloc_control_pages(struct kimage *image,
316 						unsigned int order);
317 extern void __crash_kexec(struct pt_regs *);
318 extern void crash_kexec(struct pt_regs *);
319 int kexec_should_crash(struct task_struct *);
320 int kexec_crash_loaded(void);
321 void crash_save_cpu(struct pt_regs *regs, int cpu);
322 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
323 
324 extern struct kimage *kexec_image;
325 extern struct kimage *kexec_crash_image;
326 extern int kexec_load_disabled;
327 
328 #ifndef kexec_flush_icache_page
329 #define kexec_flush_icache_page(page)
330 #endif
331 
332 /* List of defined/legal kexec flags */
333 #ifndef CONFIG_KEXEC_JUMP
334 #define KEXEC_FLAGS    KEXEC_ON_CRASH
335 #else
336 #define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
337 #endif
338 
339 /* List of defined/legal kexec file flags */
340 #define KEXEC_FILE_FLAGS	(KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
341 				 KEXEC_FILE_NO_INITRAMFS)
342 
343 /* Location of a reserved region to hold the crash kernel.
344  */
345 extern struct resource crashk_res;
346 extern struct resource crashk_low_res;
347 extern note_buf_t __percpu *crash_notes;
348 
349 /* flag to track if kexec reboot is in progress */
350 extern bool kexec_in_progress;
351 
352 int crash_shrink_memory(unsigned long new_size);
353 size_t crash_get_memory_size(void);
354 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
355 
356 void arch_kexec_protect_crashkres(void);
357 void arch_kexec_unprotect_crashkres(void);
358 
359 #ifndef page_to_boot_pfn
page_to_boot_pfn(struct page * page)360 static inline unsigned long page_to_boot_pfn(struct page *page)
361 {
362 	return page_to_pfn(page);
363 }
364 #endif
365 
366 #ifndef boot_pfn_to_page
boot_pfn_to_page(unsigned long boot_pfn)367 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
368 {
369 	return pfn_to_page(boot_pfn);
370 }
371 #endif
372 
373 #ifndef phys_to_boot_phys
phys_to_boot_phys(phys_addr_t phys)374 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
375 {
376 	return phys;
377 }
378 #endif
379 
380 #ifndef boot_phys_to_phys
boot_phys_to_phys(unsigned long boot_phys)381 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
382 {
383 	return boot_phys;
384 }
385 #endif
386 
virt_to_boot_phys(void * addr)387 static inline unsigned long virt_to_boot_phys(void *addr)
388 {
389 	return phys_to_boot_phys(__pa((unsigned long)addr));
390 }
391 
boot_phys_to_virt(unsigned long entry)392 static inline void *boot_phys_to_virt(unsigned long entry)
393 {
394 	return phys_to_virt(boot_phys_to_phys(entry));
395 }
396 
397 #ifndef arch_kexec_post_alloc_pages
arch_kexec_post_alloc_pages(void * vaddr,unsigned int pages,gfp_t gfp)398 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
399 #endif
400 
401 #ifndef arch_kexec_pre_free_pages
arch_kexec_pre_free_pages(void * vaddr,unsigned int pages)402 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
403 #endif
404 
405 #else /* !CONFIG_KEXEC_CORE */
406 struct pt_regs;
407 struct task_struct;
__crash_kexec(struct pt_regs * regs)408 static inline void __crash_kexec(struct pt_regs *regs) { }
crash_kexec(struct pt_regs * regs)409 static inline void crash_kexec(struct pt_regs *regs) { }
kexec_should_crash(struct task_struct * p)410 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
kexec_crash_loaded(void)411 static inline int kexec_crash_loaded(void) { return 0; }
412 #define kexec_in_progress false
413 #endif /* CONFIG_KEXEC_CORE */
414 
415 #endif /* !defined(__ASSEBMLY__) */
416 
417 #endif /* LINUX_KEXEC_H */
418