kexec.h (12431B)
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/* Location of a reserved region to hold the crash kernel. 24 */ 25extern struct resource crashk_res; 26extern struct resource crashk_low_res; 27extern note_buf_t __percpu *crash_notes; 28 29#ifdef CONFIG_KEXEC_CORE 30#include <linux/list.h> 31#include <linux/compat.h> 32#include <linux/ioport.h> 33#include <linux/module.h> 34#include <asm/kexec.h> 35 36/* Verify architecture specific macros are defined */ 37 38#ifndef KEXEC_SOURCE_MEMORY_LIMIT 39#error KEXEC_SOURCE_MEMORY_LIMIT not defined 40#endif 41 42#ifndef KEXEC_DESTINATION_MEMORY_LIMIT 43#error KEXEC_DESTINATION_MEMORY_LIMIT not defined 44#endif 45 46#ifndef KEXEC_CONTROL_MEMORY_LIMIT 47#error KEXEC_CONTROL_MEMORY_LIMIT not defined 48#endif 49 50#ifndef KEXEC_CONTROL_MEMORY_GFP 51#define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY) 52#endif 53 54#ifndef KEXEC_CONTROL_PAGE_SIZE 55#error KEXEC_CONTROL_PAGE_SIZE not defined 56#endif 57 58#ifndef KEXEC_ARCH 59#error KEXEC_ARCH not defined 60#endif 61 62#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT 63#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT 64#endif 65 66#ifndef KEXEC_CRASH_MEM_ALIGN 67#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE 68#endif 69 70#define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME 71 72/* 73 * This structure is used to hold the arguments that are used when loading 74 * kernel binaries. 75 */ 76 77typedef unsigned long kimage_entry_t; 78 79struct kexec_segment { 80 /* 81 * This pointer can point to user memory if kexec_load() system 82 * call is used or will point to kernel memory if 83 * kexec_file_load() system call is used. 84 * 85 * Use ->buf when expecting to deal with user memory and use ->kbuf 86 * when expecting to deal with kernel memory. 87 */ 88 union { 89 void __user *buf; 90 void *kbuf; 91 }; 92 size_t bufsz; 93 unsigned long mem; 94 size_t memsz; 95}; 96 97#ifdef CONFIG_COMPAT 98struct compat_kexec_segment { 99 compat_uptr_t buf; 100 compat_size_t bufsz; 101 compat_ulong_t mem; /* User space sees this as a (void *) ... */ 102 compat_size_t memsz; 103}; 104#endif 105 106#ifdef CONFIG_KEXEC_FILE 107struct purgatory_info { 108 /* 109 * Pointer to elf header at the beginning of kexec_purgatory. 110 * Note: kexec_purgatory is read only 111 */ 112 const Elf_Ehdr *ehdr; 113 /* 114 * Temporary, modifiable buffer for sechdrs used for relocation. 115 * This memory can be freed post image load. 116 */ 117 Elf_Shdr *sechdrs; 118 /* 119 * Temporary, modifiable buffer for stripped purgatory used for 120 * relocation. This memory can be freed post image load. 121 */ 122 void *purgatory_buf; 123}; 124 125struct kimage; 126 127typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size); 128typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf, 129 unsigned long kernel_len, char *initrd, 130 unsigned long initrd_len, char *cmdline, 131 unsigned long cmdline_len); 132typedef int (kexec_cleanup_t)(void *loader_data); 133 134#ifdef CONFIG_KEXEC_SIG 135typedef int (kexec_verify_sig_t)(const char *kernel_buf, 136 unsigned long kernel_len); 137#endif 138 139struct kexec_file_ops { 140 kexec_probe_t *probe; 141 kexec_load_t *load; 142 kexec_cleanup_t *cleanup; 143#ifdef CONFIG_KEXEC_SIG 144 kexec_verify_sig_t *verify_sig; 145#endif 146}; 147 148extern const struct kexec_file_ops * const kexec_file_loaders[]; 149 150int kexec_image_probe_default(struct kimage *image, void *buf, 151 unsigned long buf_len); 152int kexec_image_post_load_cleanup_default(struct kimage *image); 153 154/* 155 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole() 156 * will try to allocate free memory. Arch may overwrite it. 157 */ 158#ifndef KEXEC_BUF_MEM_UNKNOWN 159#define KEXEC_BUF_MEM_UNKNOWN 0 160#endif 161 162/** 163 * struct kexec_buf - parameters for finding a place for a buffer in memory 164 * @image: kexec image in which memory to search. 165 * @buffer: Contents which will be copied to the allocated memory. 166 * @bufsz: Size of @buffer. 167 * @mem: On return will have address of the buffer in memory. 168 * @memsz: Size for the buffer in memory. 169 * @buf_align: Minimum alignment needed. 170 * @buf_min: The buffer can't be placed below this address. 171 * @buf_max: The buffer can't be placed above this address. 172 * @top_down: Allocate from top of memory. 173 */ 174struct kexec_buf { 175 struct kimage *image; 176 void *buffer; 177 unsigned long bufsz; 178 unsigned long mem; 179 unsigned long memsz; 180 unsigned long buf_align; 181 unsigned long buf_min; 182 unsigned long buf_max; 183 bool top_down; 184}; 185 186int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf); 187int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, 188 void *buf, unsigned int size, 189 bool get_value); 190void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name); 191 192/* Architectures may override the below functions */ 193int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, 194 unsigned long buf_len); 195void *arch_kexec_kernel_image_load(struct kimage *image); 196int arch_kimage_file_post_load_cleanup(struct kimage *image); 197#ifdef CONFIG_KEXEC_SIG 198int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, 199 unsigned long buf_len); 200#endif 201int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf); 202 203extern int kexec_add_buffer(struct kexec_buf *kbuf); 204int kexec_locate_mem_hole(struct kexec_buf *kbuf); 205 206/* Alignment required for elf header segment */ 207#define ELF_CORE_HEADER_ALIGN 4096 208 209struct crash_mem_range { 210 u64 start, end; 211}; 212 213struct crash_mem { 214 unsigned int max_nr_ranges; 215 unsigned int nr_ranges; 216 struct crash_mem_range ranges[]; 217}; 218 219extern int crash_exclude_mem_range(struct crash_mem *mem, 220 unsigned long long mstart, 221 unsigned long long mend); 222extern int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map, 223 void **addr, unsigned long *sz); 224 225#ifndef arch_kexec_apply_relocations_add 226/* 227 * arch_kexec_apply_relocations_add - apply relocations of type RELA 228 * @pi: Purgatory to be relocated. 229 * @section: Section relocations applying to. 230 * @relsec: Section containing RELAs. 231 * @symtab: Corresponding symtab. 232 * 233 * Return: 0 on success, negative errno on error. 234 */ 235static inline int 236arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section, 237 const Elf_Shdr *relsec, const Elf_Shdr *symtab) 238{ 239 pr_err("RELA relocation unsupported.\n"); 240 return -ENOEXEC; 241} 242#endif 243 244#ifndef arch_kexec_apply_relocations 245/* 246 * arch_kexec_apply_relocations - apply relocations of type REL 247 * @pi: Purgatory to be relocated. 248 * @section: Section relocations applying to. 249 * @relsec: Section containing RELs. 250 * @symtab: Corresponding symtab. 251 * 252 * Return: 0 on success, negative errno on error. 253 */ 254static inline int 255arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section, 256 const Elf_Shdr *relsec, const Elf_Shdr *symtab) 257{ 258 pr_err("REL relocation unsupported.\n"); 259 return -ENOEXEC; 260} 261#endif 262#endif /* CONFIG_KEXEC_FILE */ 263 264#ifdef CONFIG_KEXEC_ELF 265struct kexec_elf_info { 266 /* 267 * Where the ELF binary contents are kept. 268 * Memory managed by the user of the struct. 269 */ 270 const char *buffer; 271 272 const struct elfhdr *ehdr; 273 const struct elf_phdr *proghdrs; 274}; 275 276int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr, 277 struct kexec_elf_info *elf_info); 278 279int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, 280 struct kexec_elf_info *elf_info, 281 struct kexec_buf *kbuf, 282 unsigned long *lowest_load_addr); 283 284void kexec_free_elf_info(struct kexec_elf_info *elf_info); 285int kexec_elf_probe(const char *buf, unsigned long len); 286#endif 287struct kimage { 288 kimage_entry_t head; 289 kimage_entry_t *entry; 290 kimage_entry_t *last_entry; 291 292 unsigned long start; 293 struct page *control_code_page; 294 struct page *swap_page; 295 void *vmcoreinfo_data_copy; /* locates in the crash memory */ 296 297 unsigned long nr_segments; 298 struct kexec_segment segment[KEXEC_SEGMENT_MAX]; 299 300 struct list_head control_pages; 301 struct list_head dest_pages; 302 struct list_head unusable_pages; 303 304 /* Address of next control page to allocate for crash kernels. */ 305 unsigned long control_page; 306 307 /* Flags to indicate special processing */ 308 unsigned int type : 1; 309#define KEXEC_TYPE_DEFAULT 0 310#define KEXEC_TYPE_CRASH 1 311 unsigned int preserve_context : 1; 312 /* If set, we are using file mode kexec syscall */ 313 unsigned int file_mode:1; 314 315#ifdef ARCH_HAS_KIMAGE_ARCH 316 struct kimage_arch arch; 317#endif 318 319#ifdef CONFIG_KEXEC_FILE 320 /* Additional fields for file based kexec syscall */ 321 void *kernel_buf; 322 unsigned long kernel_buf_len; 323 324 void *initrd_buf; 325 unsigned long initrd_buf_len; 326 327 char *cmdline_buf; 328 unsigned long cmdline_buf_len; 329 330 /* File operations provided by image loader */ 331 const struct kexec_file_ops *fops; 332 333 /* Image loader handling the kernel can store a pointer here */ 334 void *image_loader_data; 335 336 /* Information for loading purgatory */ 337 struct purgatory_info purgatory_info; 338#endif 339 340#ifdef CONFIG_IMA_KEXEC 341 /* Virtual address of IMA measurement buffer for kexec syscall */ 342 void *ima_buffer; 343 344 phys_addr_t ima_buffer_addr; 345 size_t ima_buffer_size; 346#endif 347 348 /* Core ELF header buffer */ 349 void *elf_headers; 350 unsigned long elf_headers_sz; 351 unsigned long elf_load_addr; 352}; 353 354/* kexec interface functions */ 355extern void machine_kexec(struct kimage *image); 356extern int machine_kexec_prepare(struct kimage *image); 357extern void machine_kexec_cleanup(struct kimage *image); 358extern int kernel_kexec(void); 359extern struct page *kimage_alloc_control_pages(struct kimage *image, 360 unsigned int order); 361int machine_kexec_post_load(struct kimage *image); 362 363extern void __crash_kexec(struct pt_regs *); 364extern void crash_kexec(struct pt_regs *); 365int kexec_should_crash(struct task_struct *); 366int kexec_crash_loaded(void); 367void crash_save_cpu(struct pt_regs *regs, int cpu); 368extern int kimage_crash_copy_vmcoreinfo(struct kimage *image); 369 370extern struct kimage *kexec_image; 371extern struct kimage *kexec_crash_image; 372extern int kexec_load_disabled; 373 374#ifndef kexec_flush_icache_page 375#define kexec_flush_icache_page(page) 376#endif 377 378/* List of defined/legal kexec flags */ 379#ifndef CONFIG_KEXEC_JUMP 380#define KEXEC_FLAGS KEXEC_ON_CRASH 381#else 382#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT) 383#endif 384 385/* List of defined/legal kexec file flags */ 386#define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \ 387 KEXEC_FILE_NO_INITRAMFS) 388 389/* flag to track if kexec reboot is in progress */ 390extern bool kexec_in_progress; 391 392int crash_shrink_memory(unsigned long new_size); 393size_t crash_get_memory_size(void); 394void crash_free_reserved_phys_range(unsigned long begin, unsigned long end); 395 396void arch_kexec_protect_crashkres(void); 397void arch_kexec_unprotect_crashkres(void); 398 399#ifndef page_to_boot_pfn 400static inline unsigned long page_to_boot_pfn(struct page *page) 401{ 402 return page_to_pfn(page); 403} 404#endif 405 406#ifndef boot_pfn_to_page 407static inline struct page *boot_pfn_to_page(unsigned long boot_pfn) 408{ 409 return pfn_to_page(boot_pfn); 410} 411#endif 412 413#ifndef phys_to_boot_phys 414static inline unsigned long phys_to_boot_phys(phys_addr_t phys) 415{ 416 return phys; 417} 418#endif 419 420#ifndef boot_phys_to_phys 421static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys) 422{ 423 return boot_phys; 424} 425#endif 426 427static inline unsigned long virt_to_boot_phys(void *addr) 428{ 429 return phys_to_boot_phys(__pa((unsigned long)addr)); 430} 431 432static inline void *boot_phys_to_virt(unsigned long entry) 433{ 434 return phys_to_virt(boot_phys_to_phys(entry)); 435} 436 437#ifndef arch_kexec_post_alloc_pages 438static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; } 439#endif 440 441#ifndef arch_kexec_pre_free_pages 442static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { } 443#endif 444 445#else /* !CONFIG_KEXEC_CORE */ 446struct pt_regs; 447struct task_struct; 448static inline void __crash_kexec(struct pt_regs *regs) { } 449static inline void crash_kexec(struct pt_regs *regs) { } 450static inline int kexec_should_crash(struct task_struct *p) { return 0; } 451static inline int kexec_crash_loaded(void) { return 0; } 452#define kexec_in_progress false 453#endif /* CONFIG_KEXEC_CORE */ 454 455#endif /* !defined(__ASSEBMLY__) */ 456 457#endif /* LINUX_KEXEC_H */