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 */ 25 extern struct resource crashk_res; 26 extern struct resource crashk_low_res; 27 extern 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 77 typedef unsigned long kimage_entry_t; 78 79 struct 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 98 struct 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 107 struct 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 }; 124 125 struct kimage; 126 127 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size); 128 typedef 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); 132 typedef int (kexec_cleanup_t)(void *loader_data); 133 134 #ifdef CONFIG_KEXEC_SIG 135 typedef int (kexec_verify_sig_t)(const char *kernel_buf, 136 unsigned long kernel_len); 137 #endif 138 139 struct 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 }; 147 148 extern const struct kexec_file_ops * const kexec_file_loaders[]; 149 150 int kexec_image_probe_default(struct kimage *image, void *buf, 151 unsigned long buf_len); 152 int 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 */ 174 struct 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 }; 185 186 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf); 187 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, 188 void *buf, unsigned int size, 189 bool get_value); 190 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name); 191 void *kexec_image_load_default(struct kimage *image); 192 193 #ifndef arch_kexec_kernel_image_probe 194 static inline int 195 arch_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 202 static 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 #ifndef arch_kexec_kernel_image_load 209 static inline void *arch_kexec_kernel_image_load(struct kimage *image) 210 { 211 return kexec_image_load_default(image); 212 } 213 #endif 214 215 extern int kexec_add_buffer(struct kexec_buf *kbuf); 216 int kexec_locate_mem_hole(struct kexec_buf *kbuf); 217 218 #ifndef arch_kexec_locate_mem_hole 219 /** 220 * arch_kexec_locate_mem_hole - Find free memory to place the segments. 221 * @kbuf: Parameters for the memory search. 222 * 223 * On success, kbuf->mem will have the start address of the memory region found. 224 * 225 * Return: 0 on success, negative errno on error. 226 */ 227 static inline int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf) 228 { 229 return kexec_locate_mem_hole(kbuf); 230 } 231 #endif 232 233 /* Alignment required for elf header segment */ 234 #define ELF_CORE_HEADER_ALIGN 4096 235 236 struct crash_mem_range { 237 u64 start, end; 238 }; 239 240 struct crash_mem { 241 unsigned int max_nr_ranges; 242 unsigned int nr_ranges; 243 struct crash_mem_range ranges[]; 244 }; 245 246 extern int crash_exclude_mem_range(struct crash_mem *mem, 247 unsigned long long mstart, 248 unsigned long long mend); 249 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map, 250 void **addr, unsigned long *sz); 251 252 #ifndef arch_kexec_apply_relocations_add 253 /* 254 * arch_kexec_apply_relocations_add - apply relocations of type RELA 255 * @pi: Purgatory to be relocated. 256 * @section: Section relocations applying to. 257 * @relsec: Section containing RELAs. 258 * @symtab: Corresponding symtab. 259 * 260 * Return: 0 on success, negative errno on error. 261 */ 262 static inline int 263 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section, 264 const Elf_Shdr *relsec, const Elf_Shdr *symtab) 265 { 266 pr_err("RELA relocation unsupported.\n"); 267 return -ENOEXEC; 268 } 269 #endif 270 271 #ifndef arch_kexec_apply_relocations 272 /* 273 * arch_kexec_apply_relocations - apply relocations of type REL 274 * @pi: Purgatory to be relocated. 275 * @section: Section relocations applying to. 276 * @relsec: Section containing RELs. 277 * @symtab: Corresponding symtab. 278 * 279 * Return: 0 on success, negative errno on error. 280 */ 281 static inline int 282 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section, 283 const Elf_Shdr *relsec, const Elf_Shdr *symtab) 284 { 285 pr_err("REL relocation unsupported.\n"); 286 return -ENOEXEC; 287 } 288 #endif 289 #endif /* CONFIG_KEXEC_FILE */ 290 291 #ifdef CONFIG_KEXEC_ELF 292 struct kexec_elf_info { 293 /* 294 * Where the ELF binary contents are kept. 295 * Memory managed by the user of the struct. 296 */ 297 const char *buffer; 298 299 const struct elfhdr *ehdr; 300 const struct elf_phdr *proghdrs; 301 }; 302 303 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr, 304 struct kexec_elf_info *elf_info); 305 306 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, 307 struct kexec_elf_info *elf_info, 308 struct kexec_buf *kbuf, 309 unsigned long *lowest_load_addr); 310 311 void kexec_free_elf_info(struct kexec_elf_info *elf_info); 312 int kexec_elf_probe(const char *buf, unsigned long len); 313 #endif 314 struct kimage { 315 kimage_entry_t head; 316 kimage_entry_t *entry; 317 kimage_entry_t *last_entry; 318 319 unsigned long start; 320 struct page *control_code_page; 321 struct page *swap_page; 322 void *vmcoreinfo_data_copy; /* locates in the crash memory */ 323 324 unsigned long nr_segments; 325 struct kexec_segment segment[KEXEC_SEGMENT_MAX]; 326 327 struct list_head control_pages; 328 struct list_head dest_pages; 329 struct list_head unusable_pages; 330 331 /* Address of next control page to allocate for crash kernels. */ 332 unsigned long control_page; 333 334 /* Flags to indicate special processing */ 335 unsigned int type : 1; 336 #define KEXEC_TYPE_DEFAULT 0 337 #define KEXEC_TYPE_CRASH 1 338 unsigned int preserve_context : 1; 339 /* If set, we are using file mode kexec syscall */ 340 unsigned int file_mode:1; 341 342 #ifdef ARCH_HAS_KIMAGE_ARCH 343 struct kimage_arch arch; 344 #endif 345 346 #ifdef CONFIG_KEXEC_FILE 347 /* Additional fields for file based kexec syscall */ 348 void *kernel_buf; 349 unsigned long kernel_buf_len; 350 351 void *initrd_buf; 352 unsigned long initrd_buf_len; 353 354 char *cmdline_buf; 355 unsigned long cmdline_buf_len; 356 357 /* File operations provided by image loader */ 358 const struct kexec_file_ops *fops; 359 360 /* Image loader handling the kernel can store a pointer here */ 361 void *image_loader_data; 362 363 /* Information for loading purgatory */ 364 struct purgatory_info purgatory_info; 365 #endif 366 367 #ifdef CONFIG_IMA_KEXEC 368 /* Virtual address of IMA measurement buffer for kexec syscall */ 369 void *ima_buffer; 370 371 phys_addr_t ima_buffer_addr; 372 size_t ima_buffer_size; 373 #endif 374 375 /* Core ELF header buffer */ 376 void *elf_headers; 377 unsigned long elf_headers_sz; 378 unsigned long elf_load_addr; 379 }; 380 381 /* kexec interface functions */ 382 extern void machine_kexec(struct kimage *image); 383 extern int machine_kexec_prepare(struct kimage *image); 384 extern void machine_kexec_cleanup(struct kimage *image); 385 extern int kernel_kexec(void); 386 extern struct page *kimage_alloc_control_pages(struct kimage *image, 387 unsigned int order); 388 389 #ifndef machine_kexec_post_load 390 static inline int machine_kexec_post_load(struct kimage *image) { return 0; } 391 #endif 392 393 extern void __crash_kexec(struct pt_regs *); 394 extern void crash_kexec(struct pt_regs *); 395 int kexec_should_crash(struct task_struct *); 396 int kexec_crash_loaded(void); 397 void crash_save_cpu(struct pt_regs *regs, int cpu); 398 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image); 399 400 extern struct kimage *kexec_image; 401 extern struct kimage *kexec_crash_image; 402 extern int kexec_load_disabled; 403 404 #ifndef kexec_flush_icache_page 405 #define kexec_flush_icache_page(page) 406 #endif 407 408 /* List of defined/legal kexec flags */ 409 #ifndef CONFIG_KEXEC_JUMP 410 #define KEXEC_FLAGS KEXEC_ON_CRASH 411 #else 412 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT) 413 #endif 414 415 /* List of defined/legal kexec file flags */ 416 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \ 417 KEXEC_FILE_NO_INITRAMFS) 418 419 /* flag to track if kexec reboot is in progress */ 420 extern bool kexec_in_progress; 421 422 int crash_shrink_memory(unsigned long new_size); 423 size_t crash_get_memory_size(void); 424 425 #ifndef arch_kexec_protect_crashkres 426 /* 427 * Protection mechanism for crashkernel reserved memory after 428 * the kdump kernel is loaded. 429 * 430 * Provide an empty default implementation here -- architecture 431 * code may override this 432 */ 433 static inline void arch_kexec_protect_crashkres(void) { } 434 #endif 435 436 #ifndef arch_kexec_unprotect_crashkres 437 static inline void arch_kexec_unprotect_crashkres(void) { } 438 #endif 439 440 #ifndef page_to_boot_pfn 441 static inline unsigned long page_to_boot_pfn(struct page *page) 442 { 443 return page_to_pfn(page); 444 } 445 #endif 446 447 #ifndef boot_pfn_to_page 448 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn) 449 { 450 return pfn_to_page(boot_pfn); 451 } 452 #endif 453 454 #ifndef phys_to_boot_phys 455 static inline unsigned long phys_to_boot_phys(phys_addr_t phys) 456 { 457 return phys; 458 } 459 #endif 460 461 #ifndef boot_phys_to_phys 462 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys) 463 { 464 return boot_phys; 465 } 466 #endif 467 468 #ifndef crash_free_reserved_phys_range 469 static inline void crash_free_reserved_phys_range(unsigned long begin, unsigned long end) 470 { 471 unsigned long addr; 472 473 for (addr = begin; addr < end; addr += PAGE_SIZE) 474 free_reserved_page(boot_pfn_to_page(addr >> PAGE_SHIFT)); 475 } 476 #endif 477 478 static inline unsigned long virt_to_boot_phys(void *addr) 479 { 480 return phys_to_boot_phys(__pa((unsigned long)addr)); 481 } 482 483 static inline void *boot_phys_to_virt(unsigned long entry) 484 { 485 return phys_to_virt(boot_phys_to_phys(entry)); 486 } 487 488 #ifndef arch_kexec_post_alloc_pages 489 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; } 490 #endif 491 492 #ifndef arch_kexec_pre_free_pages 493 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { } 494 #endif 495 496 #else /* !CONFIG_KEXEC_CORE */ 497 struct pt_regs; 498 struct task_struct; 499 static inline void __crash_kexec(struct pt_regs *regs) { } 500 static inline void crash_kexec(struct pt_regs *regs) { } 501 static inline int kexec_should_crash(struct task_struct *p) { return 0; } 502 static inline int kexec_crash_loaded(void) { return 0; } 503 #define kexec_in_progress false 504 #endif /* CONFIG_KEXEC_CORE */ 505 506 #ifdef CONFIG_KEXEC_SIG 507 void set_kexec_sig_enforced(void); 508 #else 509 static inline void set_kexec_sig_enforced(void) {} 510 #endif 511 512 #endif /* !defined(__ASSEBMLY__) */ 513 514 #endif /* LINUX_KEXEC_H */ 515