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/vmcore_info.h>
19#include <linux/crash_reserve.h>
20#include <asm/io.h>
21#include <linux/range.h>
22
23#include <uapi/linux/kexec.h>
24#include <linux/verification.h>
25
26extern note_buf_t __percpu *crash_notes;
27
28#ifdef CONFIG_KEXEC_CORE
29#include <linux/list.h>
30#include <linux/compat.h>
31#include <linux/ioport.h>
32#include <linux/module.h>
33#include <linux/highmem.h>
34#include <asm/kexec.h>
35#include <linux/crash_core.h>
36
37/* Verify architecture specific macros are defined */
38
39#ifndef KEXEC_SOURCE_MEMORY_LIMIT
40#error KEXEC_SOURCE_MEMORY_LIMIT not defined
41#endif
42
43#ifndef KEXEC_DESTINATION_MEMORY_LIMIT
44#error KEXEC_DESTINATION_MEMORY_LIMIT not defined
45#endif
46
47#ifndef KEXEC_CONTROL_MEMORY_LIMIT
48#error KEXEC_CONTROL_MEMORY_LIMIT not defined
49#endif
50
51#ifndef KEXEC_CONTROL_MEMORY_GFP
52#define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
53#endif
54
55#ifndef KEXEC_CONTROL_PAGE_SIZE
56#error KEXEC_CONTROL_PAGE_SIZE not defined
57#endif
58
59#ifndef KEXEC_ARCH
60#error KEXEC_ARCH not defined
61#endif
62
63#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
64#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
65#endif
66
67#ifndef KEXEC_CRASH_MEM_ALIGN
68#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
69#endif
70
71#define KEXEC_CORE_NOTE_NAME	CRASH_CORE_NOTE_NAME
72
73/*
74 * This structure is used to hold the arguments that are used when loading
75 * kernel binaries.
76 */
77
78typedef unsigned long kimage_entry_t;
79
80struct kexec_segment {
81	/*
82	 * This pointer can point to user memory if kexec_load() system
83	 * call is used or will point to kernel memory if
84	 * kexec_file_load() system call is used.
85	 *
86	 * Use ->buf when expecting to deal with user memory and use ->kbuf
87	 * when expecting to deal with kernel memory.
88	 */
89	union {
90		void __user *buf;
91		void *kbuf;
92	};
93	size_t bufsz;
94	unsigned long mem;
95	size_t memsz;
96};
97
98#ifdef CONFIG_COMPAT
99struct compat_kexec_segment {
100	compat_uptr_t buf;
101	compat_size_t bufsz;
102	compat_ulong_t mem;	/* User space sees this as a (void *) ... */
103	compat_size_t memsz;
104};
105#endif
106
107#ifdef CONFIG_KEXEC_FILE
108struct purgatory_info {
109	/*
110	 * Pointer to elf header at the beginning of kexec_purgatory.
111	 * Note: kexec_purgatory is read only
112	 */
113	const Elf_Ehdr *ehdr;
114	/*
115	 * Temporary, modifiable buffer for sechdrs used for relocation.
116	 * This memory can be freed post image load.
117	 */
118	Elf_Shdr *sechdrs;
119	/*
120	 * Temporary, modifiable buffer for stripped purgatory used for
121	 * relocation. This memory can be freed post image load.
122	 */
123	void *purgatory_buf;
124};
125
126struct kimage;
127
128typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
129typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
130			     unsigned long kernel_len, char *initrd,
131			     unsigned long initrd_len, char *cmdline,
132			     unsigned long cmdline_len);
133typedef int (kexec_cleanup_t)(void *loader_data);
134
135#ifdef CONFIG_KEXEC_SIG
136typedef int (kexec_verify_sig_t)(const char *kernel_buf,
137				 unsigned long kernel_len);
138#endif
139
140struct kexec_file_ops {
141	kexec_probe_t *probe;
142	kexec_load_t *load;
143	kexec_cleanup_t *cleanup;
144#ifdef CONFIG_KEXEC_SIG
145	kexec_verify_sig_t *verify_sig;
146#endif
147};
148
149extern const struct kexec_file_ops * const kexec_file_loaders[];
150
151int kexec_image_probe_default(struct kimage *image, void *buf,
152			      unsigned long buf_len);
153int kexec_image_post_load_cleanup_default(struct kimage *image);
154
155/*
156 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole()
157 * will try to allocate free memory. Arch may overwrite it.
158 */
159#ifndef KEXEC_BUF_MEM_UNKNOWN
160#define KEXEC_BUF_MEM_UNKNOWN 0
161#endif
162
163/**
164 * struct kexec_buf - parameters for finding a place for a buffer in memory
165 * @image:	kexec image in which memory to search.
166 * @buffer:	Contents which will be copied to the allocated memory.
167 * @bufsz:	Size of @buffer.
168 * @mem:	On return will have address of the buffer in memory.
169 * @memsz:	Size for the buffer in memory.
170 * @buf_align:	Minimum alignment needed.
171 * @buf_min:	The buffer can't be placed below this address.
172 * @buf_max:	The buffer can't be placed above this address.
173 * @top_down:	Allocate from top of memory.
174 */
175struct kexec_buf {
176	struct kimage *image;
177	void *buffer;
178	unsigned long bufsz;
179	unsigned long mem;
180	unsigned long memsz;
181	unsigned long buf_align;
182	unsigned long buf_min;
183	unsigned long buf_max;
184	bool top_down;
185};
186
187int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
188int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
189				   void *buf, unsigned int size,
190				   bool get_value);
191void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
192
193#ifndef arch_kexec_kernel_image_probe
194static inline int
195arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len)
196{
197	return kexec_image_probe_default(image, buf, buf_len);
198}
199#endif
200
201#ifndef arch_kimage_file_post_load_cleanup
202static inline int arch_kimage_file_post_load_cleanup(struct kimage *image)
203{
204	return kexec_image_post_load_cleanup_default(image);
205}
206#endif
207
208#ifdef CONFIG_KEXEC_SIG
209#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
210int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len);
211#endif
212#endif
213
214extern int kexec_add_buffer(struct kexec_buf *kbuf);
215int kexec_locate_mem_hole(struct kexec_buf *kbuf);
216
217#ifndef arch_kexec_locate_mem_hole
218/**
219 * arch_kexec_locate_mem_hole - Find free memory to place the segments.
220 * @kbuf:                       Parameters for the memory search.
221 *
222 * On success, kbuf->mem will have the start address of the memory region found.
223 *
224 * Return: 0 on success, negative errno on error.
225 */
226static inline int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
227{
228	return kexec_locate_mem_hole(kbuf);
229}
230#endif
231
232#ifndef arch_kexec_apply_relocations_add
233/*
234 * arch_kexec_apply_relocations_add - apply relocations of type RELA
235 * @pi:		Purgatory to be relocated.
236 * @section:	Section relocations applying to.
237 * @relsec:	Section containing RELAs.
238 * @symtab:	Corresponding symtab.
239 *
240 * Return: 0 on success, negative errno on error.
241 */
242static inline int
243arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
244				 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
245{
246	pr_err("RELA relocation unsupported.\n");
247	return -ENOEXEC;
248}
249#endif
250
251#ifndef arch_kexec_apply_relocations
252/*
253 * arch_kexec_apply_relocations - apply relocations of type REL
254 * @pi:		Purgatory to be relocated.
255 * @section:	Section relocations applying to.
256 * @relsec:	Section containing RELs.
257 * @symtab:	Corresponding symtab.
258 *
259 * Return: 0 on success, negative errno on error.
260 */
261static inline int
262arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
263			     const Elf_Shdr *relsec, const Elf_Shdr *symtab)
264{
265	pr_err("REL relocation unsupported.\n");
266	return -ENOEXEC;
267}
268#endif
269#endif /* CONFIG_KEXEC_FILE */
270
271#ifdef CONFIG_KEXEC_ELF
272struct kexec_elf_info {
273	/*
274	 * Where the ELF binary contents are kept.
275	 * Memory managed by the user of the struct.
276	 */
277	const char *buffer;
278
279	const struct elfhdr *ehdr;
280	const struct elf_phdr *proghdrs;
281};
282
283int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
284			       struct kexec_elf_info *elf_info);
285
286int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
287			 struct kexec_elf_info *elf_info,
288			 struct kexec_buf *kbuf,
289			 unsigned long *lowest_load_addr);
290
291void kexec_free_elf_info(struct kexec_elf_info *elf_info);
292int kexec_elf_probe(const char *buf, unsigned long len);
293#endif
294struct kimage {
295	kimage_entry_t head;
296	kimage_entry_t *entry;
297	kimage_entry_t *last_entry;
298
299	unsigned long start;
300	struct page *control_code_page;
301	struct page *swap_page;
302	void *vmcoreinfo_data_copy; /* locates in the crash memory */
303
304	unsigned long nr_segments;
305	struct kexec_segment segment[KEXEC_SEGMENT_MAX];
306
307	struct list_head control_pages;
308	struct list_head dest_pages;
309	struct list_head unusable_pages;
310
311	/* Address of next control page to allocate for crash kernels. */
312	unsigned long control_page;
313
314	/* Flags to indicate special processing */
315	unsigned int type : 1;
316#define KEXEC_TYPE_DEFAULT 0
317#define KEXEC_TYPE_CRASH   1
318	unsigned int preserve_context : 1;
319	/* If set, we are using file mode kexec syscall */
320	unsigned int file_mode:1;
321#ifdef CONFIG_CRASH_HOTPLUG
322	/* If set, allow changes to elfcorehdr of kexec_load'd image */
323	unsigned int update_elfcorehdr:1;
324#endif
325
326#ifdef ARCH_HAS_KIMAGE_ARCH
327	struct kimage_arch arch;
328#endif
329
330#ifdef CONFIG_KEXEC_FILE
331	/* Additional fields for file based kexec syscall */
332	void *kernel_buf;
333	unsigned long kernel_buf_len;
334
335	void *initrd_buf;
336	unsigned long initrd_buf_len;
337
338	char *cmdline_buf;
339	unsigned long cmdline_buf_len;
340
341	/* File operations provided by image loader */
342	const struct kexec_file_ops *fops;
343
344	/* Image loader handling the kernel can store a pointer here */
345	void *image_loader_data;
346
347	/* Information for loading purgatory */
348	struct purgatory_info purgatory_info;
349#endif
350
351#ifdef CONFIG_CRASH_HOTPLUG
352	int hp_action;
353	int elfcorehdr_index;
354	bool elfcorehdr_updated;
355#endif
356
357#ifdef CONFIG_IMA_KEXEC
358	/* Virtual address of IMA measurement buffer for kexec syscall */
359	void *ima_buffer;
360
361	phys_addr_t ima_buffer_addr;
362	size_t ima_buffer_size;
363#endif
364
365	/* Core ELF header buffer */
366	void *elf_headers;
367	unsigned long elf_headers_sz;
368	unsigned long elf_load_addr;
369};
370
371/* kexec interface functions */
372extern void machine_kexec(struct kimage *image);
373extern int machine_kexec_prepare(struct kimage *image);
374extern void machine_kexec_cleanup(struct kimage *image);
375extern int kernel_kexec(void);
376extern struct page *kimage_alloc_control_pages(struct kimage *image,
377						unsigned int order);
378
379#ifndef machine_kexec_post_load
380static inline int machine_kexec_post_load(struct kimage *image) { return 0; }
381#endif
382
383extern struct kimage *kexec_image;
384extern struct kimage *kexec_crash_image;
385
386bool kexec_load_permitted(int kexec_image_type);
387
388#ifndef kexec_flush_icache_page
389#define kexec_flush_icache_page(page)
390#endif
391
392/* List of defined/legal kexec flags */
393#ifndef CONFIG_KEXEC_JUMP
394#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_UPDATE_ELFCOREHDR)
395#else
396#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT | KEXEC_UPDATE_ELFCOREHDR)
397#endif
398
399/* List of defined/legal kexec file flags */
400#define KEXEC_FILE_FLAGS	(KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
401				 KEXEC_FILE_NO_INITRAMFS | KEXEC_FILE_DEBUG)
402
403/* flag to track if kexec reboot is in progress */
404extern bool kexec_in_progress;
405
406#ifndef page_to_boot_pfn
407static inline unsigned long page_to_boot_pfn(struct page *page)
408{
409	return page_to_pfn(page);
410}
411#endif
412
413#ifndef boot_pfn_to_page
414static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
415{
416	return pfn_to_page(boot_pfn);
417}
418#endif
419
420#ifndef phys_to_boot_phys
421static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
422{
423	return phys;
424}
425#endif
426
427#ifndef boot_phys_to_phys
428static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
429{
430	return boot_phys;
431}
432#endif
433
434#ifndef crash_free_reserved_phys_range
435static inline void crash_free_reserved_phys_range(unsigned long begin, unsigned long end)
436{
437	unsigned long addr;
438
439	for (addr = begin; addr < end; addr += PAGE_SIZE)
440		free_reserved_page(boot_pfn_to_page(addr >> PAGE_SHIFT));
441}
442#endif
443
444static inline unsigned long virt_to_boot_phys(void *addr)
445{
446	return phys_to_boot_phys(__pa((unsigned long)addr));
447}
448
449static inline void *boot_phys_to_virt(unsigned long entry)
450{
451	return phys_to_virt(boot_phys_to_phys(entry));
452}
453
454#ifndef arch_kexec_post_alloc_pages
455static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
456#endif
457
458#ifndef arch_kexec_pre_free_pages
459static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
460#endif
461
462extern bool kexec_file_dbg_print;
463
464#define kexec_dprintk(fmt, ...)					\
465	printk("%s" fmt,					\
466	       kexec_file_dbg_print ? KERN_INFO : KERN_DEBUG,	\
467	       ##__VA_ARGS__)
468
469#else /* !CONFIG_KEXEC_CORE */
470struct pt_regs;
471struct task_struct;
472static inline void __crash_kexec(struct pt_regs *regs) { }
473static inline void crash_kexec(struct pt_regs *regs) { }
474static inline int kexec_should_crash(struct task_struct *p) { return 0; }
475static inline int kexec_crash_loaded(void) { return 0; }
476#define kexec_in_progress false
477#endif /* CONFIG_KEXEC_CORE */
478
479#ifdef CONFIG_KEXEC_SIG
480void set_kexec_sig_enforced(void);
481#else
482static inline void set_kexec_sig_enforced(void) {}
483#endif
484
485#endif /* !defined(__ASSEBMLY__) */
486
487#endif /* LINUX_KEXEC_H */
488