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 #include <linux/range.h> 21 22 #include <uapi/linux/kexec.h> 23 #include <linux/verification.h> 24 25 /* Location of a reserved region to hold the crash kernel. 26 */ 27 extern struct resource crashk_res; 28 extern struct resource crashk_low_res; 29 extern note_buf_t __percpu *crash_notes; 30 31 #ifdef CONFIG_KEXEC_CORE 32 #include <linux/list.h> 33 #include <linux/compat.h> 34 #include <linux/ioport.h> 35 #include <linux/module.h> 36 #include <asm/kexec.h> 37 38 /* Verify architecture specific macros are defined */ 39 40 #ifndef KEXEC_SOURCE_MEMORY_LIMIT 41 #error KEXEC_SOURCE_MEMORY_LIMIT not defined 42 #endif 43 44 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT 45 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined 46 #endif 47 48 #ifndef KEXEC_CONTROL_MEMORY_LIMIT 49 #error KEXEC_CONTROL_MEMORY_LIMIT not defined 50 #endif 51 52 #ifndef KEXEC_CONTROL_MEMORY_GFP 53 #define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY) 54 #endif 55 56 #ifndef KEXEC_CONTROL_PAGE_SIZE 57 #error KEXEC_CONTROL_PAGE_SIZE not defined 58 #endif 59 60 #ifndef KEXEC_ARCH 61 #error KEXEC_ARCH not defined 62 #endif 63 64 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT 65 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT 66 #endif 67 68 #ifndef KEXEC_CRASH_MEM_ALIGN 69 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE 70 #endif 71 72 #define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME 73 74 /* 75 * This structure is used to hold the arguments that are used when loading 76 * kernel binaries. 77 */ 78 79 typedef unsigned long kimage_entry_t; 80 81 struct kexec_segment { 82 /* 83 * This pointer can point to user memory if kexec_load() system 84 * call is used or will point to kernel memory if 85 * kexec_file_load() system call is used. 86 * 87 * Use ->buf when expecting to deal with user memory and use ->kbuf 88 * when expecting to deal with kernel memory. 89 */ 90 union { 91 void __user *buf; 92 void *kbuf; 93 }; 94 size_t bufsz; 95 unsigned long mem; 96 size_t memsz; 97 }; 98 99 #ifdef CONFIG_COMPAT 100 struct compat_kexec_segment { 101 compat_uptr_t buf; 102 compat_size_t bufsz; 103 compat_ulong_t mem; /* User space sees this as a (void *) ... */ 104 compat_size_t memsz; 105 }; 106 #endif 107 108 #ifdef CONFIG_KEXEC_FILE 109 struct purgatory_info { 110 /* 111 * Pointer to elf header at the beginning of kexec_purgatory. 112 * Note: kexec_purgatory is read only 113 */ 114 const Elf_Ehdr *ehdr; 115 /* 116 * Temporary, modifiable buffer for sechdrs used for relocation. 117 * This memory can be freed post image load. 118 */ 119 Elf_Shdr *sechdrs; 120 /* 121 * Temporary, modifiable buffer for stripped purgatory used for 122 * relocation. This memory can be freed post image load. 123 */ 124 void *purgatory_buf; 125 }; 126 127 struct kimage; 128 129 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size); 130 typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf, 131 unsigned long kernel_len, char *initrd, 132 unsigned long initrd_len, char *cmdline, 133 unsigned long cmdline_len); 134 typedef int (kexec_cleanup_t)(void *loader_data); 135 136 #ifdef CONFIG_KEXEC_SIG 137 typedef int (kexec_verify_sig_t)(const char *kernel_buf, 138 unsigned long kernel_len); 139 #endif 140 141 struct kexec_file_ops { 142 kexec_probe_t *probe; 143 kexec_load_t *load; 144 kexec_cleanup_t *cleanup; 145 #ifdef CONFIG_KEXEC_SIG 146 kexec_verify_sig_t *verify_sig; 147 #endif 148 }; 149 150 extern const struct kexec_file_ops * const kexec_file_loaders[]; 151 152 int kexec_image_probe_default(struct kimage *image, void *buf, 153 unsigned long buf_len); 154 int kexec_image_post_load_cleanup_default(struct kimage *image); 155 156 /* 157 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole() 158 * will try to allocate free memory. Arch may overwrite it. 159 */ 160 #ifndef KEXEC_BUF_MEM_UNKNOWN 161 #define KEXEC_BUF_MEM_UNKNOWN 0 162 #endif 163 164 /** 165 * struct kexec_buf - parameters for finding a place for a buffer in memory 166 * @image: kexec image in which memory to search. 167 * @buffer: Contents which will be copied to the allocated memory. 168 * @bufsz: Size of @buffer. 169 * @mem: On return will have address of the buffer in memory. 170 * @memsz: Size for the buffer in memory. 171 * @buf_align: Minimum alignment needed. 172 * @buf_min: The buffer can't be placed below this address. 173 * @buf_max: The buffer can't be placed above this address. 174 * @top_down: Allocate from top of memory. 175 */ 176 struct kexec_buf { 177 struct kimage *image; 178 void *buffer; 179 unsigned long bufsz; 180 unsigned long mem; 181 unsigned long memsz; 182 unsigned long buf_align; 183 unsigned long buf_min; 184 unsigned long buf_max; 185 bool top_down; 186 }; 187 188 int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf); 189 int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, 190 void *buf, unsigned int size, 191 bool get_value); 192 void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name); 193 194 #ifndef arch_kexec_kernel_image_probe 195 static inline int 196 arch_kexec_kernel_image_probe(struct kimage *image, void *buf, unsigned long buf_len) 197 { 198 return kexec_image_probe_default(image, buf, buf_len); 199 } 200 #endif 201 202 #ifndef arch_kimage_file_post_load_cleanup 203 static inline int arch_kimage_file_post_load_cleanup(struct kimage *image) 204 { 205 return kexec_image_post_load_cleanup_default(image); 206 } 207 #endif 208 209 #ifdef CONFIG_KEXEC_SIG 210 #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION 211 int kexec_kernel_verify_pe_sig(const char *kernel, unsigned long kernel_len); 212 #endif 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 { 237 unsigned int max_nr_ranges; 238 unsigned int nr_ranges; 239 struct range ranges[]; 240 }; 241 242 extern int crash_exclude_mem_range(struct crash_mem *mem, 243 unsigned long long mstart, 244 unsigned long long mend); 245 extern int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map, 246 void **addr, unsigned long *sz); 247 248 #ifndef arch_kexec_apply_relocations_add 249 /* 250 * arch_kexec_apply_relocations_add - apply relocations of type RELA 251 * @pi: Purgatory to be relocated. 252 * @section: Section relocations applying to. 253 * @relsec: Section containing RELAs. 254 * @symtab: Corresponding symtab. 255 * 256 * Return: 0 on success, negative errno on error. 257 */ 258 static inline int 259 arch_kexec_apply_relocations_add(struct purgatory_info *pi, Elf_Shdr *section, 260 const Elf_Shdr *relsec, const Elf_Shdr *symtab) 261 { 262 pr_err("RELA relocation unsupported.\n"); 263 return -ENOEXEC; 264 } 265 #endif 266 267 #ifndef arch_kexec_apply_relocations 268 /* 269 * arch_kexec_apply_relocations - apply relocations of type REL 270 * @pi: Purgatory to be relocated. 271 * @section: Section relocations applying to. 272 * @relsec: Section containing RELs. 273 * @symtab: Corresponding symtab. 274 * 275 * Return: 0 on success, negative errno on error. 276 */ 277 static inline int 278 arch_kexec_apply_relocations(struct purgatory_info *pi, Elf_Shdr *section, 279 const Elf_Shdr *relsec, const Elf_Shdr *symtab) 280 { 281 pr_err("REL relocation unsupported.\n"); 282 return -ENOEXEC; 283 } 284 #endif 285 #endif /* CONFIG_KEXEC_FILE */ 286 287 #ifdef CONFIG_KEXEC_ELF 288 struct kexec_elf_info { 289 /* 290 * Where the ELF binary contents are kept. 291 * Memory managed by the user of the struct. 292 */ 293 const char *buffer; 294 295 const struct elfhdr *ehdr; 296 const struct elf_phdr *proghdrs; 297 }; 298 299 int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr, 300 struct kexec_elf_info *elf_info); 301 302 int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, 303 struct kexec_elf_info *elf_info, 304 struct kexec_buf *kbuf, 305 unsigned long *lowest_load_addr); 306 307 void kexec_free_elf_info(struct kexec_elf_info *elf_info); 308 int kexec_elf_probe(const char *buf, unsigned long len); 309 #endif 310 struct kimage { 311 kimage_entry_t head; 312 kimage_entry_t *entry; 313 kimage_entry_t *last_entry; 314 315 unsigned long start; 316 struct page *control_code_page; 317 struct page *swap_page; 318 void *vmcoreinfo_data_copy; /* locates in the crash memory */ 319 320 unsigned long nr_segments; 321 struct kexec_segment segment[KEXEC_SEGMENT_MAX]; 322 323 struct list_head control_pages; 324 struct list_head dest_pages; 325 struct list_head unusable_pages; 326 327 /* Address of next control page to allocate for crash kernels. */ 328 unsigned long control_page; 329 330 /* Flags to indicate special processing */ 331 unsigned int type : 1; 332 #define KEXEC_TYPE_DEFAULT 0 333 #define KEXEC_TYPE_CRASH 1 334 unsigned int preserve_context : 1; 335 /* If set, we are using file mode kexec syscall */ 336 unsigned int file_mode:1; 337 338 #ifdef ARCH_HAS_KIMAGE_ARCH 339 struct kimage_arch arch; 340 #endif 341 342 #ifdef CONFIG_KEXEC_FILE 343 /* Additional fields for file based kexec syscall */ 344 void *kernel_buf; 345 unsigned long kernel_buf_len; 346 347 void *initrd_buf; 348 unsigned long initrd_buf_len; 349 350 char *cmdline_buf; 351 unsigned long cmdline_buf_len; 352 353 /* File operations provided by image loader */ 354 const struct kexec_file_ops *fops; 355 356 /* Image loader handling the kernel can store a pointer here */ 357 void *image_loader_data; 358 359 /* Information for loading purgatory */ 360 struct purgatory_info purgatory_info; 361 #endif 362 363 #ifdef CONFIG_IMA_KEXEC 364 /* Virtual address of IMA measurement buffer for kexec syscall */ 365 void *ima_buffer; 366 367 phys_addr_t ima_buffer_addr; 368 size_t ima_buffer_size; 369 #endif 370 371 /* Core ELF header buffer */ 372 void *elf_headers; 373 unsigned long elf_headers_sz; 374 unsigned long elf_load_addr; 375 }; 376 377 /* kexec interface functions */ 378 extern void machine_kexec(struct kimage *image); 379 extern int machine_kexec_prepare(struct kimage *image); 380 extern void machine_kexec_cleanup(struct kimage *image); 381 extern int kernel_kexec(void); 382 extern struct page *kimage_alloc_control_pages(struct kimage *image, 383 unsigned int order); 384 385 #ifndef machine_kexec_post_load 386 static inline int machine_kexec_post_load(struct kimage *image) { return 0; } 387 #endif 388 389 extern void __crash_kexec(struct pt_regs *); 390 extern void crash_kexec(struct pt_regs *); 391 int kexec_should_crash(struct task_struct *); 392 int kexec_crash_loaded(void); 393 void crash_save_cpu(struct pt_regs *regs, int cpu); 394 extern int kimage_crash_copy_vmcoreinfo(struct kimage *image); 395 396 extern struct kimage *kexec_image; 397 extern struct kimage *kexec_crash_image; 398 399 bool kexec_load_permitted(int kexec_image_type); 400 401 #ifndef kexec_flush_icache_page 402 #define kexec_flush_icache_page(page) 403 #endif 404 405 /* List of defined/legal kexec flags */ 406 #ifndef CONFIG_KEXEC_JUMP 407 #define KEXEC_FLAGS KEXEC_ON_CRASH 408 #else 409 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT) 410 #endif 411 412 /* List of defined/legal kexec file flags */ 413 #define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \ 414 KEXEC_FILE_NO_INITRAMFS) 415 416 /* flag to track if kexec reboot is in progress */ 417 extern bool kexec_in_progress; 418 419 int crash_shrink_memory(unsigned long new_size); 420 ssize_t crash_get_memory_size(void); 421 422 #ifndef arch_kexec_protect_crashkres 423 /* 424 * Protection mechanism for crashkernel reserved memory after 425 * the kdump kernel is loaded. 426 * 427 * Provide an empty default implementation here -- architecture 428 * code may override this 429 */ 430 static inline void arch_kexec_protect_crashkres(void) { } 431 #endif 432 433 #ifndef arch_kexec_unprotect_crashkres 434 static inline void arch_kexec_unprotect_crashkres(void) { } 435 #endif 436 437 #ifndef page_to_boot_pfn 438 static inline unsigned long page_to_boot_pfn(struct page *page) 439 { 440 return page_to_pfn(page); 441 } 442 #endif 443 444 #ifndef boot_pfn_to_page 445 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn) 446 { 447 return pfn_to_page(boot_pfn); 448 } 449 #endif 450 451 #ifndef phys_to_boot_phys 452 static inline unsigned long phys_to_boot_phys(phys_addr_t phys) 453 { 454 return phys; 455 } 456 #endif 457 458 #ifndef boot_phys_to_phys 459 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys) 460 { 461 return boot_phys; 462 } 463 #endif 464 465 #ifndef crash_free_reserved_phys_range 466 static inline void crash_free_reserved_phys_range(unsigned long begin, unsigned long end) 467 { 468 unsigned long addr; 469 470 for (addr = begin; addr < end; addr += PAGE_SIZE) 471 free_reserved_page(boot_pfn_to_page(addr >> PAGE_SHIFT)); 472 } 473 #endif 474 475 static inline unsigned long virt_to_boot_phys(void *addr) 476 { 477 return phys_to_boot_phys(__pa((unsigned long)addr)); 478 } 479 480 static inline void *boot_phys_to_virt(unsigned long entry) 481 { 482 return phys_to_virt(boot_phys_to_phys(entry)); 483 } 484 485 #ifndef arch_kexec_post_alloc_pages 486 static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; } 487 #endif 488 489 #ifndef arch_kexec_pre_free_pages 490 static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { } 491 #endif 492 493 #else /* !CONFIG_KEXEC_CORE */ 494 struct pt_regs; 495 struct task_struct; 496 static inline void __crash_kexec(struct pt_regs *regs) { } 497 static inline void crash_kexec(struct pt_regs *regs) { } 498 static inline int kexec_should_crash(struct task_struct *p) { return 0; } 499 static inline int kexec_crash_loaded(void) { return 0; } 500 #define kexec_in_progress false 501 #endif /* CONFIG_KEXEC_CORE */ 502 503 #ifdef CONFIG_KEXEC_SIG 504 void set_kexec_sig_enforced(void); 505 #else 506 static inline void set_kexec_sig_enforced(void) {} 507 #endif 508 509 #endif /* !defined(__ASSEBMLY__) */ 510 511 #endif /* LINUX_KEXEC_H */ 512