at v5.13 12 kB view raw
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#ifdef CONFIG_KEXEC_CORE 24#include <linux/list.h> 25#include <linux/compat.h> 26#include <linux/ioport.h> 27#include <linux/module.h> 28#include <asm/kexec.h> 29 30/* Verify architecture specific macros are defined */ 31 32#ifndef KEXEC_SOURCE_MEMORY_LIMIT 33#error KEXEC_SOURCE_MEMORY_LIMIT not defined 34#endif 35 36#ifndef KEXEC_DESTINATION_MEMORY_LIMIT 37#error KEXEC_DESTINATION_MEMORY_LIMIT not defined 38#endif 39 40#ifndef KEXEC_CONTROL_MEMORY_LIMIT 41#error KEXEC_CONTROL_MEMORY_LIMIT not defined 42#endif 43 44#ifndef KEXEC_CONTROL_MEMORY_GFP 45#define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY) 46#endif 47 48#ifndef KEXEC_CONTROL_PAGE_SIZE 49#error KEXEC_CONTROL_PAGE_SIZE not defined 50#endif 51 52#ifndef KEXEC_ARCH 53#error KEXEC_ARCH not defined 54#endif 55 56#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT 57#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT 58#endif 59 60#ifndef KEXEC_CRASH_MEM_ALIGN 61#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE 62#endif 63 64#define KEXEC_CORE_NOTE_NAME CRASH_CORE_NOTE_NAME 65 66/* 67 * This structure is used to hold the arguments that are used when loading 68 * kernel binaries. 69 */ 70 71typedef unsigned long kimage_entry_t; 72 73struct kexec_segment { 74 /* 75 * This pointer can point to user memory if kexec_load() system 76 * call is used or will point to kernel memory if 77 * kexec_file_load() system call is used. 78 * 79 * Use ->buf when expecting to deal with user memory and use ->kbuf 80 * when expecting to deal with kernel memory. 81 */ 82 union { 83 void __user *buf; 84 void *kbuf; 85 }; 86 size_t bufsz; 87 unsigned long mem; 88 size_t memsz; 89}; 90 91#ifdef CONFIG_COMPAT 92struct compat_kexec_segment { 93 compat_uptr_t buf; 94 compat_size_t bufsz; 95 compat_ulong_t mem; /* User space sees this as a (void *) ... */ 96 compat_size_t memsz; 97}; 98#endif 99 100#ifdef CONFIG_KEXEC_FILE 101struct purgatory_info { 102 /* 103 * Pointer to elf header at the beginning of kexec_purgatory. 104 * Note: kexec_purgatory is read only 105 */ 106 const Elf_Ehdr *ehdr; 107 /* 108 * Temporary, modifiable buffer for sechdrs used for relocation. 109 * This memory can be freed post image load. 110 */ 111 Elf_Shdr *sechdrs; 112 /* 113 * Temporary, modifiable buffer for stripped purgatory used for 114 * relocation. This memory can be freed post image load. 115 */ 116 void *purgatory_buf; 117}; 118 119struct kimage; 120 121typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size); 122typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf, 123 unsigned long kernel_len, char *initrd, 124 unsigned long initrd_len, char *cmdline, 125 unsigned long cmdline_len); 126typedef int (kexec_cleanup_t)(void *loader_data); 127 128#ifdef CONFIG_KEXEC_SIG 129typedef int (kexec_verify_sig_t)(const char *kernel_buf, 130 unsigned long kernel_len); 131#endif 132 133struct kexec_file_ops { 134 kexec_probe_t *probe; 135 kexec_load_t *load; 136 kexec_cleanup_t *cleanup; 137#ifdef CONFIG_KEXEC_SIG 138 kexec_verify_sig_t *verify_sig; 139#endif 140}; 141 142extern const struct kexec_file_ops * const kexec_file_loaders[]; 143 144int kexec_image_probe_default(struct kimage *image, void *buf, 145 unsigned long buf_len); 146int kexec_image_post_load_cleanup_default(struct kimage *image); 147 148/* 149 * If kexec_buf.mem is set to this value, kexec_locate_mem_hole() 150 * will try to allocate free memory. Arch may overwrite it. 151 */ 152#ifndef KEXEC_BUF_MEM_UNKNOWN 153#define KEXEC_BUF_MEM_UNKNOWN 0 154#endif 155 156/** 157 * struct kexec_buf - parameters for finding a place for a buffer in memory 158 * @image: kexec image in which memory to search. 159 * @buffer: Contents which will be copied to the allocated memory. 160 * @bufsz: Size of @buffer. 161 * @mem: On return will have address of the buffer in memory. 162 * @memsz: Size for the buffer in memory. 163 * @buf_align: Minimum alignment needed. 164 * @buf_min: The buffer can't be placed below this address. 165 * @buf_max: The buffer can't be placed above this address. 166 * @top_down: Allocate from top of memory. 167 */ 168struct kexec_buf { 169 struct kimage *image; 170 void *buffer; 171 unsigned long bufsz; 172 unsigned long mem; 173 unsigned long memsz; 174 unsigned long buf_align; 175 unsigned long buf_min; 176 unsigned long buf_max; 177 bool top_down; 178}; 179 180int kexec_load_purgatory(struct kimage *image, struct kexec_buf *kbuf); 181int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name, 182 void *buf, unsigned int size, 183 bool get_value); 184void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name); 185 186/* Architectures may override the below functions */ 187int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, 188 unsigned long buf_len); 189void *arch_kexec_kernel_image_load(struct kimage *image); 190int arch_kexec_apply_relocations_add(struct purgatory_info *pi, 191 Elf_Shdr *section, 192 const Elf_Shdr *relsec, 193 const Elf_Shdr *symtab); 194int arch_kexec_apply_relocations(struct purgatory_info *pi, 195 Elf_Shdr *section, 196 const Elf_Shdr *relsec, 197 const Elf_Shdr *symtab); 198int arch_kimage_file_post_load_cleanup(struct kimage *image); 199#ifdef CONFIG_KEXEC_SIG 200int arch_kexec_kernel_verify_sig(struct kimage *image, void *buf, 201 unsigned long buf_len); 202#endif 203int arch_kexec_locate_mem_hole(struct kexec_buf *kbuf); 204 205extern int kexec_add_buffer(struct kexec_buf *kbuf); 206int kexec_locate_mem_hole(struct kexec_buf *kbuf); 207 208/* Alignment required for elf header segment */ 209#define ELF_CORE_HEADER_ALIGN 4096 210 211struct crash_mem_range { 212 u64 start, end; 213}; 214 215struct crash_mem { 216 unsigned int max_nr_ranges; 217 unsigned int nr_ranges; 218 struct crash_mem_range ranges[]; 219}; 220 221extern int crash_exclude_mem_range(struct crash_mem *mem, 222 unsigned long long mstart, 223 unsigned long long mend); 224extern int crash_prepare_elf64_headers(struct crash_mem *mem, int kernel_map, 225 void **addr, unsigned long *sz); 226#endif /* CONFIG_KEXEC_FILE */ 227 228#ifdef CONFIG_KEXEC_ELF 229struct kexec_elf_info { 230 /* 231 * Where the ELF binary contents are kept. 232 * Memory managed by the user of the struct. 233 */ 234 const char *buffer; 235 236 const struct elfhdr *ehdr; 237 const struct elf_phdr *proghdrs; 238}; 239 240int kexec_build_elf_info(const char *buf, size_t len, struct elfhdr *ehdr, 241 struct kexec_elf_info *elf_info); 242 243int kexec_elf_load(struct kimage *image, struct elfhdr *ehdr, 244 struct kexec_elf_info *elf_info, 245 struct kexec_buf *kbuf, 246 unsigned long *lowest_load_addr); 247 248void kexec_free_elf_info(struct kexec_elf_info *elf_info); 249int kexec_elf_probe(const char *buf, unsigned long len); 250#endif 251struct kimage { 252 kimage_entry_t head; 253 kimage_entry_t *entry; 254 kimage_entry_t *last_entry; 255 256 unsigned long start; 257 struct page *control_code_page; 258 struct page *swap_page; 259 void *vmcoreinfo_data_copy; /* locates in the crash memory */ 260 261 unsigned long nr_segments; 262 struct kexec_segment segment[KEXEC_SEGMENT_MAX]; 263 264 struct list_head control_pages; 265 struct list_head dest_pages; 266 struct list_head unusable_pages; 267 268 /* Address of next control page to allocate for crash kernels. */ 269 unsigned long control_page; 270 271 /* Flags to indicate special processing */ 272 unsigned int type : 1; 273#define KEXEC_TYPE_DEFAULT 0 274#define KEXEC_TYPE_CRASH 1 275 unsigned int preserve_context : 1; 276 /* If set, we are using file mode kexec syscall */ 277 unsigned int file_mode:1; 278 279#ifdef ARCH_HAS_KIMAGE_ARCH 280 struct kimage_arch arch; 281#endif 282 283#ifdef CONFIG_KEXEC_FILE 284 /* Additional fields for file based kexec syscall */ 285 void *kernel_buf; 286 unsigned long kernel_buf_len; 287 288 void *initrd_buf; 289 unsigned long initrd_buf_len; 290 291 char *cmdline_buf; 292 unsigned long cmdline_buf_len; 293 294 /* File operations provided by image loader */ 295 const struct kexec_file_ops *fops; 296 297 /* Image loader handling the kernel can store a pointer here */ 298 void *image_loader_data; 299 300 /* Information for loading purgatory */ 301 struct purgatory_info purgatory_info; 302#endif 303 304#ifdef CONFIG_IMA_KEXEC 305 /* Virtual address of IMA measurement buffer for kexec syscall */ 306 void *ima_buffer; 307 308 phys_addr_t ima_buffer_addr; 309 size_t ima_buffer_size; 310#endif 311 312 /* Core ELF header buffer */ 313 void *elf_headers; 314 unsigned long elf_headers_sz; 315 unsigned long elf_load_addr; 316}; 317 318/* kexec interface functions */ 319extern void machine_kexec(struct kimage *image); 320extern int machine_kexec_prepare(struct kimage *image); 321extern void machine_kexec_cleanup(struct kimage *image); 322extern int kernel_kexec(void); 323extern struct page *kimage_alloc_control_pages(struct kimage *image, 324 unsigned int order); 325int machine_kexec_post_load(struct kimage *image); 326 327extern void __crash_kexec(struct pt_regs *); 328extern void crash_kexec(struct pt_regs *); 329int kexec_should_crash(struct task_struct *); 330int kexec_crash_loaded(void); 331void crash_save_cpu(struct pt_regs *regs, int cpu); 332extern int kimage_crash_copy_vmcoreinfo(struct kimage *image); 333 334extern struct kimage *kexec_image; 335extern struct kimage *kexec_crash_image; 336extern int kexec_load_disabled; 337 338#ifndef kexec_flush_icache_page 339#define kexec_flush_icache_page(page) 340#endif 341 342/* List of defined/legal kexec flags */ 343#ifndef CONFIG_KEXEC_JUMP 344#define KEXEC_FLAGS KEXEC_ON_CRASH 345#else 346#define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT) 347#endif 348 349/* List of defined/legal kexec file flags */ 350#define KEXEC_FILE_FLAGS (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \ 351 KEXEC_FILE_NO_INITRAMFS) 352 353/* Location of a reserved region to hold the crash kernel. 354 */ 355extern struct resource crashk_res; 356extern struct resource crashk_low_res; 357extern note_buf_t __percpu *crash_notes; 358 359/* flag to track if kexec reboot is in progress */ 360extern bool kexec_in_progress; 361 362int crash_shrink_memory(unsigned long new_size); 363size_t crash_get_memory_size(void); 364void crash_free_reserved_phys_range(unsigned long begin, unsigned long end); 365 366void arch_kexec_protect_crashkres(void); 367void arch_kexec_unprotect_crashkres(void); 368 369#ifndef page_to_boot_pfn 370static inline unsigned long page_to_boot_pfn(struct page *page) 371{ 372 return page_to_pfn(page); 373} 374#endif 375 376#ifndef boot_pfn_to_page 377static inline struct page *boot_pfn_to_page(unsigned long boot_pfn) 378{ 379 return pfn_to_page(boot_pfn); 380} 381#endif 382 383#ifndef phys_to_boot_phys 384static inline unsigned long phys_to_boot_phys(phys_addr_t phys) 385{ 386 return phys; 387} 388#endif 389 390#ifndef boot_phys_to_phys 391static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys) 392{ 393 return boot_phys; 394} 395#endif 396 397static inline unsigned long virt_to_boot_phys(void *addr) 398{ 399 return phys_to_boot_phys(__pa((unsigned long)addr)); 400} 401 402static inline void *boot_phys_to_virt(unsigned long entry) 403{ 404 return phys_to_virt(boot_phys_to_phys(entry)); 405} 406 407#ifndef arch_kexec_post_alloc_pages 408static inline int arch_kexec_post_alloc_pages(void *vaddr, unsigned int pages, gfp_t gfp) { return 0; } 409#endif 410 411#ifndef arch_kexec_pre_free_pages 412static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) { } 413#endif 414 415#else /* !CONFIG_KEXEC_CORE */ 416struct pt_regs; 417struct task_struct; 418static inline void __crash_kexec(struct pt_regs *regs) { } 419static inline void crash_kexec(struct pt_regs *regs) { } 420static inline int kexec_should_crash(struct task_struct *p) { return 0; } 421static inline int kexec_crash_loaded(void) { return 0; } 422#define kexec_in_progress false 423#endif /* CONFIG_KEXEC_CORE */ 424 425#endif /* !defined(__ASSEBMLY__) */ 426 427#endif /* LINUX_KEXEC_H */