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_CRASH_DUMP
29#include <linux/prandom.h>
30#endif
31
32#ifdef CONFIG_KEXEC_CORE
33#include <linux/list.h>
34#include <linux/compat.h>
35#include <linux/ioport.h>
36#include <linux/module.h>
37#include <linux/highmem.h>
38#include <asm/kexec.h>
39#include <linux/crash_core.h>
40
41/* Verify architecture specific macros are defined */
42
43#ifndef KEXEC_SOURCE_MEMORY_LIMIT
44#error KEXEC_SOURCE_MEMORY_LIMIT not defined
45#endif
46
47#ifndef KEXEC_DESTINATION_MEMORY_LIMIT
48#error KEXEC_DESTINATION_MEMORY_LIMIT not defined
49#endif
50
51#ifndef KEXEC_CONTROL_MEMORY_LIMIT
52#error KEXEC_CONTROL_MEMORY_LIMIT not defined
53#endif
54
55#ifndef KEXEC_CONTROL_MEMORY_GFP
56#define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
57#endif
58
59#ifndef KEXEC_CONTROL_PAGE_SIZE
60#error KEXEC_CONTROL_PAGE_SIZE not defined
61#endif
62
63#ifndef KEXEC_ARCH
64#error KEXEC_ARCH not defined
65#endif
66
67#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
68#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
69#endif
70
71#ifndef KEXEC_CRASH_MEM_ALIGN
72#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
73#endif
74
75/*
76 * This structure is used to hold the arguments that are used when loading
77 * kernel binaries.
78 */
79
80typedef unsigned long kimage_entry_t;
81
82/*
83 * This is a copy of the UAPI struct kexec_segment and must be identical
84 * to it because it gets copied straight from user space into kernel
85 * memory. Do not modify this structure unless you change the way segments
86 * get ingested from user space.
87 */
88struct kexec_segment {
89 /*
90 * This pointer can point to user memory if kexec_load() system
91 * call is used or will point to kernel memory if
92 * kexec_file_load() system call is used.
93 *
94 * Use ->buf when expecting to deal with user memory and use ->kbuf
95 * when expecting to deal with kernel memory.
96 */
97 union {
98 void __user *buf;
99 void *kbuf;
100 };
101 size_t bufsz;
102 unsigned long mem;
103 size_t memsz;
104};
105
106#ifdef CONFIG_COMPAT
107struct compat_kexec_segment {
108 compat_uptr_t buf;
109 compat_size_t bufsz;
110 compat_ulong_t mem; /* User space sees this as a (void *) ... */
111 compat_size_t memsz;
112};
113#endif
114
115#ifdef CONFIG_KEXEC_FILE
116struct purgatory_info {
117 /*
118 * Pointer to elf header at the beginning of kexec_purgatory.
119 * Note: kexec_purgatory is read only
120 */
121 const Elf_Ehdr *ehdr;
122 /*
123 * Temporary, modifiable buffer for sechdrs used for relocation.
124 * This memory can be freed post image load.
125 */
126 Elf_Shdr *sechdrs;
127 /*
128 * Temporary, modifiable buffer for stripped purgatory used for
129 * relocation. This memory can be freed post image load.
130 */
131 void *purgatory_buf;
132};
133
134struct kimage;
135
136typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
137typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
138 unsigned long kernel_len, char *initrd,
139 unsigned long initrd_len, char *cmdline,
140 unsigned long cmdline_len);
141typedef int (kexec_cleanup_t)(void *loader_data);
142
143#ifdef CONFIG_KEXEC_SIG
144typedef int (kexec_verify_sig_t)(const char *kernel_buf,
145 unsigned long kernel_len);
146#endif
147
148struct kexec_file_ops {
149 kexec_probe_t *probe;
150 kexec_load_t *load;
151 kexec_cleanup_t *cleanup;
152#ifdef CONFIG_KEXEC_SIG
153 kexec_verify_sig_t *verify_sig;
154#endif
155};
156
157extern const struct kexec_file_ops * const kexec_file_loaders[];
158
159int kexec_image_probe_default(struct kimage *image, void *buf,
160 unsigned long buf_len);
161int kexec_image_post_load_cleanup_default(struct kimage *image);
162
163/*
164 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole()
165 * will try to allocate free memory. Arch may overwrite it.
166 */
167#ifndef KEXEC_BUF_MEM_UNKNOWN
168#define KEXEC_BUF_MEM_UNKNOWN 0
169#endif
170
171/**
172 * struct kexec_buf - parameters for finding a place for a buffer in memory
173 * @image: kexec image in which memory to search.
174 * @buffer: Contents which will be copied to the allocated memory.
175 * @bufsz: Size of @buffer.
176 * @mem: On return will have address of the buffer in memory.
177 * @memsz: Size for the buffer in memory.
178 * @buf_align: Minimum alignment needed.
179 * @buf_min: The buffer can't be placed below this address.
180 * @buf_max: The buffer can't be placed above this address.
181 * @cma: CMA page if the buffer is backed by CMA.
182 * @top_down: Allocate from top of memory.
183 * @random: Place the buffer at a random position.
184 */
185struct kexec_buf {
186 struct kimage *image;
187 void *buffer;
188 unsigned long bufsz;
189 unsigned long mem;
190 unsigned long memsz;
191 unsigned long buf_align;
192 unsigned long buf_min;
193 unsigned long buf_max;
194 struct page *cma;
195 bool top_down;
196#ifdef CONFIG_CRASH_DUMP
197 bool random;
198#endif
199};
200
201
202#ifdef CONFIG_CRASH_DUMP
203static inline void kexec_random_range_start(unsigned long start,
204 unsigned long end,
205 struct kexec_buf *kbuf,
206 unsigned long *temp_start)
207{
208 unsigned short i;
209
210 if (kbuf->random) {
211 get_random_bytes(&i, sizeof(unsigned short));
212 *temp_start = start + (end - start) / USHRT_MAX * i;
213 }
214}
215#else
216static inline void kexec_random_range_start(unsigned long start,
217 unsigned long end,
218 struct kexec_buf *kbuf,
219 unsigned long *temp_start)
220{}
221#endif
222
223int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf);
224int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
225 void *buf, unsigned int size,
226 bool get_value);
227void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name);
228
229#ifndef arch_kexec_kernel_image_probe
230static inline int
231arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len)
232{
233 return kexec_image_probe_default(image, buf, buf_len);
234}
235#endif
236
237#ifndef arch_kimage_file_post_load_cleanup
238static inline int arch_kimage_file_post_load_cleanup(struct kimage *image)
239{
240 return kexec_image_post_load_cleanup_default(image);
241}
242#endif
243
244#ifndef arch_check_excluded_range
245static inline int arch_check_excluded_range(struct kimage *image,
246 unsigned long start,
247 unsigned long end)
248{
249 return 0;
250}
251#endif
252
253#ifdef CONFIG_KEXEC_SIG
254#ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION
255int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len);
256#endif
257#endif
258
259extern int kexec_add_buffer(struct kexec_buf *kbuf);
260int kexec_locate_mem_hole(struct kexec_buf *kbuf);
261
262#ifndef arch_kexec_locate_mem_hole
263/**
264 * arch_kexec_locate_mem_hole - Find free memory to place the segments.
265 * @kbuf: Parameters for the memory search.
266 *
267 * On success, kbuf->mem will have the start address of the memory region found.
268 *
269 * Return: 0 on success, negative errno on error.
270 */
271static inline int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf)
272{
273 return kexec_locate_mem_hole(kbuf);
274}
275#endif
276
277#ifndef arch_kexec_apply_relocations_add
278/*
279 * arch_kexec_apply_relocations_add - apply relocations of type RELA
280 * @pi: Purgatory to be relocated.
281 * @section: Section relocations applying to.
282 * @relsec: Section containing RELAs.
283 * @symtab: Corresponding symtab.
284 *
285 * Return: 0 on success, negative errno on error.
286 */
287static inline int
288arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section,
289 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
290{
291 pr_err("RELA relocation unsupported.\n");
292 return -ENOEXEC;
293}
294#endif
295
296#ifndef arch_kexec_apply_relocations
297/*
298 * arch_kexec_apply_relocations - apply relocations of type REL
299 * @pi: Purgatory to be relocated.
300 * @section: Section relocations applying to.
301 * @relsec: Section containing RELs.
302 * @symtab: Corresponding symtab.
303 *
304 * Return: 0 on success, negative errno on error.
305 */
306static inline int
307arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section,
308 const Elf_Shdr *relsec, const Elf_Shdr *symtab)
309{
310 pr_err("REL relocation unsupported.\n");
311 return -ENOEXEC;
312}
313#endif
314#endif /* CONFIG_KEXEC_FILE */
315
316#ifdef CONFIG_KEXEC_ELF
317struct kexec_elf_info {
318 /*
319 * Where the ELF binary contents are kept.
320 * Memory managed by the user of the struct.
321 */
322 const char *buffer;
323
324 const struct elfhdr *ehdr;
325 const struct elf_phdr *proghdrs;
326};
327
328int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr,
329 struct kexec_elf_info *elf_info);
330
331int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr,
332 struct kexec_elf_info *elf_info,
333 struct kexec_buf *kbuf,
334 unsigned long *lowest_load_addr);
335
336void kexec_free_elf_info(struct kexec_elf_info *elf_info);
337int kexec_elf_probe(const char *buf, unsigned long len);
338#endif
339struct kimage {
340 kimage_entry_t head;
341 kimage_entry_t *entry;
342 kimage_entry_t *last_entry;
343
344 unsigned long start;
345 struct page *control_code_page;
346 struct page *swap_page;
347 void *vmcoreinfo_data_copy; /* locates in the crash memory */
348
349 unsigned long nr_segments;
350 struct kexec_segment segment[KEXEC_SEGMENT_MAX];
351 struct page *segment_cma[KEXEC_SEGMENT_MAX];
352
353 struct list_head control_pages;
354 struct list_head dest_pages;
355 struct list_head unusable_pages;
356
357 /* Address of next control page to allocate for crash kernels. */
358 unsigned long control_page;
359
360 /* Flags to indicate special processing */
361 unsigned int type : 1;
362#define KEXEC_TYPE_DEFAULT 0
363#define KEXEC_TYPE_CRASH 1
364 unsigned int preserve_context : 1;
365 /* If set, we are using file mode kexec syscall */
366 unsigned int file_mode:1;
367#ifdef CONFIG_CRASH_HOTPLUG
368 /* If set, it is safe to update kexec segments that are
369 * excluded from SHA calculation.
370 */
371 unsigned int hotplug_support:1;
372#endif
373 unsigned int no_cma:1;
374
375#ifdef ARCH_HAS_KIMAGE_ARCH
376 struct kimage_arch arch;
377#endif
378
379#ifdef CONFIG_KEXEC_FILE
380 /* Additional fields for file based kexec syscall */
381 void *kernel_buf;
382 unsigned long kernel_buf_len;
383
384 void *initrd_buf;
385 unsigned long initrd_buf_len;
386
387 char *cmdline_buf;
388 unsigned long cmdline_buf_len;
389
390 /* File operations provided by image loader */
391 const struct kexec_file_ops *fops;
392
393 /* Image loader handling the kernel can store a pointer here */
394 void *image_loader_data;
395
396 /* Information for loading purgatory */
397 struct purgatory_info purgatory_info;
398
399 /* Force carrying over the DTB from the current boot */
400 bool force_dtb;
401#endif
402
403#ifdef CONFIG_CRASH_HOTPLUG
404 int hp_action;
405 int elfcorehdr_index;
406 bool elfcorehdr_updated;
407#endif
408
409#ifdef CONFIG_IMA_KEXEC
410 /* Virtual address of IMA measurement buffer for kexec syscall */
411 void *ima_buffer;
412
413 phys_addr_t ima_buffer_addr;
414 size_t ima_buffer_size;
415
416 unsigned long ima_segment_index;
417 bool is_ima_segment_index_set;
418#endif
419
420 struct {
421 struct kexec_segment *scratch;
422 phys_addr_t fdt;
423 } kho;
424
425 /* Core ELF header buffer */
426 void *elf_headers;
427 unsigned long elf_headers_sz;
428 unsigned long elf_load_addr;
429
430 /* dm crypt keys buffer */
431 unsigned long dm_crypt_keys_addr;
432 unsigned long dm_crypt_keys_sz;
433};
434
435/* kexec interface functions */
436extern void machine_kexec(struct kimage *image);
437extern int machine_kexec_prepare(struct kimage *image);
438extern void machine_kexec_cleanup(struct kimage *image);
439extern int kernel_kexec(void);
440extern struct page *kimage_alloc_control_pages(struct kimage *image,
441 unsigned int order);
442
443#ifndef machine_kexec_post_load
444static inline int machine_kexec_post_load(struct kimage *image) { return 0; }
445#endif
446
447extern struct kimage *kexec_image;
448extern struct kimage *kexec_crash_image;
449
450bool kexec_load_permitted(int kexec_image_type);
451
452#ifndef kexec_flush_icache_page
453#define kexec_flush_icache_page(page)
454#endif
455
456/* List of defined/legal kexec flags */
457#ifndef CONFIG_KEXEC_JUMP
458#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_UPDATE_ELFCOREHDR | KEXEC_CRASH_HOTPLUG_SUPPORT)
459#else
460#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT | KEXEC_UPDATE_ELFCOREHDR | \
461 KEXEC_CRASH_HOTPLUG_SUPPORT)
462#endif
463
464/* List of defined/legal kexec file flags */
465#define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
466 KEXEC_FILE_NO_INITRAMFS | KEXEC_FILE_DEBUG | \
467 KEXEC_FILE_NO_CMA | KEXEC_FILE_FORCE_DTB)
468
469/* flag to track if kexec reboot is in progress */
470extern bool kexec_in_progress;
471
472#ifndef page_to_boot_pfn
473static inline unsigned long page_to_boot_pfn(struct page *page)
474{
475 return page_to_pfn(page);
476}
477#endif
478
479#ifndef boot_pfn_to_page
480static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
481{
482 return pfn_to_page(boot_pfn);
483}
484#endif
485
486#ifndef phys_to_boot_phys
487static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
488{
489 return phys;
490}
491#endif
492
493#ifndef boot_phys_to_phys
494static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
495{
496 return boot_phys;
497}
498#endif
499
500#ifndef crash_free_reserved_phys_range
501static inline void crash_free_reserved_phys_range(unsigned long begin, unsigned long end)
502{
503 unsigned long addr;
504
505 for (addr = begin; addr < end; addr += PAGE_SIZE)
506 free_reserved_page(page: boot_pfn_to_page(boot_pfn: addr >> PAGE_SHIFT));
507}
508#endif
509
510static inline unsigned long virt_to_boot_phys(void *addr)
511{
512 return phys_to_boot_phys(__pa((unsigned long)addr));
513}
514
515static inline void *boot_phys_to_virt(unsigned long entry)
516{
517 return phys_to_virt(address: boot_phys_to_phys(boot_phys: entry));
518}
519
520#ifndef arch_kexec_post_alloc_pages
521static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; }
522#endif
523
524#ifndef arch_kexec_pre_free_pages
525static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { }
526#endif
527
528extern bool kexec_file_dbg_print;
529
530#define kexec_dprintk(fmt, arg...) \
531 do { if (kexec_file_dbg_print) pr_info(fmt, ##arg); } while (0)
532
533extern void *kimage_map_segment(struct kimage *image, unsigned long addr, unsigned long size);
534extern void kimage_unmap_segment(void *buffer);
535#else /* !CONFIG_KEXEC_CORE */
536struct pt_regs;
537struct task_struct;
538struct kimage;
539static inline void __crash_kexec(struct pt_regs *regs) { }
540static inline void crash_kexec(struct pt_regs *regs) { }
541static inline int kexec_should_crash(struct task_struct *p) { return 0; }
542static inline int kexec_crash_loaded(void) { return 0; }
543static inline void *kimage_map_segment(struct kimage *image, unsigned long addr, unsigned long size)
544{ return NULL; }
545static inline void kimage_unmap_segment(void *buffer) { }
546#define kexec_in_progress false
547#endif /* CONFIG_KEXEC_CORE */
548
549#ifdef CONFIG_KEXEC_SIG
550void set_kexec_sig_enforced(void);
551#else
552static inline void set_kexec_sig_enforced(void) {}
553#endif
554
555#endif /* !defined(__ASSEBMLY__) */
556
557#endif /* LINUX_KEXEC_H */
558