include/linux/kexec.h

   1 #ifndef LINUX_KEXEC_H
   2 #define LINUX_KEXEC_H
   3
   4 #define IND_DESTINATION_BIT 0
   5 #define IND_INDIRECTION_BIT 1
   6 #define IND_DONE_BIT        2
   7 #define IND_SOURCE_BIT      3
   8
   9 #define IND_DESTINATION  (1 << IND_DESTINATION_BIT)
  10 #define IND_INDIRECTION  (1 << IND_INDIRECTION_BIT)
  11 #define IND_DONE         (1 << IND_DONE_BIT)
  12 #define IND_SOURCE       (1 << IND_SOURCE_BIT)
  13 #define IND_FLAGS (IND_DESTINATION | IND_INDIRECTION | IND_DONE | IND_SOURCE)
  14
  15 #if !defined(__ASSEMBLY__)
  16
  17 #include <asm/io.h>
  18
  19 #include <uapi/linux/kexec.h>
  20
  21 #ifdef CONFIG_KEXEC_CORE
  22 #include <linux/list.h>
  23 #include <linux/linkage.h>
  24 #include <linux/compat.h>
  25 #include <linux/ioport.h>
  26 #include <linux/elfcore.h>
  27 #include <linux/elf.h>
  28 #include <linux/module.h>
  29 #include <asm/kexec.h>
  30
  31 /* Verify architecture specific macros are defined */
  32
  33 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
  34 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
  35 #endif
  36
  37 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
  38 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
  39 #endif
  40
  41 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
  42 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
  43 #endif
  44
  45 #ifndef KEXEC_CONTROL_MEMORY_GFP
  46 #define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
  47 #endif
  48
  49 #ifndef KEXEC_CONTROL_PAGE_SIZE
  50 #error KEXEC_CONTROL_PAGE_SIZE not defined
  51 #endif
  52
  53 #ifndef KEXEC_ARCH
  54 #error KEXEC_ARCH not defined
  55 #endif
  56
  57 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
  58 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
  59 #endif
  60
  61 #ifndef KEXEC_CRASH_MEM_ALIGN
  62 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
  63 #endif
  64
  65 #define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
  66 #define KEXEC_CORE_NOTE_NAME "CORE"
  67 #define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
  68 #define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
  69 /*
  70  * The per-cpu notes area is a list of notes terminated by a "NULL"
  71  * note header.  For kdump, the code in vmcore.c runs in the context
  72  * of the second kernel to combine them into one note.
  73  */
  74 #ifndef KEXEC_NOTE_BYTES
  75 #define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) +                \
  76                             KEXEC_CORE_NOTE_NAME_BYTES +                \
  77                             KEXEC_CORE_NOTE_DESC_BYTES )
  78 #endif
  79
  80 /*
  81  * This structure is used to hold the arguments that are used when loading
  82  * kernel binaries.
  83  */
  84
  85 typedef unsigned long kimage_entry_t;
  86
  87 struct kexec_segment {
  88         /*
  89          * This pointer can point to user memory if kexec_load() system
  90          * call is used or will point to kernel memory if
  91          * kexec_file_load() system call is used.
  92          *
  93          * Use ->buf when expecting to deal with user memory and use ->kbuf
  94          * when expecting to deal with kernel memory.
  95          */
  96         union {
  97                 void __user *buf;
  98                 void *kbuf;
  99         };
 100         size_t bufsz;
 101         unsigned long mem;
 102         size_t memsz;
 103 };
 104
 105 #ifdef CONFIG_COMPAT
 106 struct compat_kexec_segment {
 107         compat_uptr_t buf;
 108         compat_size_t bufsz;
 109         compat_ulong_t mem;     /* User space sees this as a (void *) ... */
 110         compat_size_t memsz;
 111 };
 112 #endif
 113
 114 #ifdef CONFIG_KEXEC_FILE
 115 struct purgatory_info {
 116         /* Pointer to elf header of read only purgatory */
 117         Elf_Ehdr *ehdr;
 118
 119         /* Pointer to purgatory sechdrs which are modifiable */
 120         Elf_Shdr *sechdrs;
 121         /*
 122          * Temporary buffer location where purgatory is loaded and relocated
 123          * This memory can be freed post image load
 124          */
 125         void *purgatory_buf;
 126
 127         /* Address where purgatory is finally loaded and is executed from */
 128         unsigned long purgatory_load_addr;
 129 };
 130
 131 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
 132 typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
 133                              unsigned long kernel_len, char *initrd,
 134                              unsigned long initrd_len, char *cmdline,
 135                              unsigned long cmdline_len);
 136 typedef int (kexec_cleanup_t)(void *loader_data);
 137
 138 #ifdef CONFIG_KEXEC_VERIFY_SIG
 139 typedef int (kexec_verify_sig_t)(const char *kernel_buf,
 140                                  unsigned long kernel_len);
 141 #endif
 142
 143 struct kexec_file_ops {
 144         kexec_probe_t *probe;
 145         kexec_load_t *load;
 146         kexec_cleanup_t *cleanup;
 147 #ifdef CONFIG_KEXEC_VERIFY_SIG
 148         kexec_verify_sig_t *verify_sig;
 149 #endif
 150 };
 151 #endif
 152
 153 struct kimage {
 154         kimage_entry_t head;
 155         kimage_entry_t *entry;
 156         kimage_entry_t *last_entry;
 157
 158         unsigned long start;
 159         struct page *control_code_page;
 160         struct page *swap_page;
 161
 162         unsigned long nr_segments;
 163         struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 164
 165         struct list_head control_pages;
 166         struct list_head dest_pages;
 167         struct list_head unusable_pages;
 168
 169         /* Address of next control page to allocate for crash kernels. */
 170         unsigned long control_page;
 171
 172         /* Flags to indicate special processing */
 173         unsigned int type : 1;
 174 #define KEXEC_TYPE_DEFAULT 0
 175 #define KEXEC_TYPE_CRASH   1
 176         unsigned int preserve_context : 1;
 177         /* If set, we are using file mode kexec syscall */
 178         unsigned int file_mode:1;
 179
 180 #ifdef ARCH_HAS_KIMAGE_ARCH
 181         struct kimage_arch arch;
 182 #endif
 183
 184 #ifdef CONFIG_KEXEC_FILE
 185         /* Additional fields for file based kexec syscall */
 186         void *kernel_buf;
 187         unsigned long kernel_buf_len;
 188
 189         void *initrd_buf;
 190         unsigned long initrd_buf_len;
 191
 192         char *cmdline_buf;
 193         unsigned long cmdline_buf_len;
 194
 195         /* File operations provided by image loader */
 196         struct kexec_file_ops *fops;
 197
 198         /* Image loader handling the kernel can store a pointer here */
 199         void *image_loader_data;
 200
 201         /* Information for loading purgatory */
 202         struct purgatory_info purgatory_info;
 203 #endif
 204 };
 205
 206 /* kexec interface functions */
 207 extern void machine_kexec(struct kimage *image);
 208 extern int machine_kexec_prepare(struct kimage *image);
 209 extern void machine_kexec_cleanup(struct kimage *image);
 210 extern asmlinkage long sys_kexec_load(unsigned long entry,
 211                                         unsigned long nr_segments,
 212                                         struct kexec_segment __user *segments,
 213                                         unsigned long flags);
 214 extern int kernel_kexec(void);
 215 extern int kexec_add_buffer(struct kimage *image, char *buffer,
 216                             unsigned long bufsz, unsigned long memsz,
 217                             unsigned long buf_align, unsigned long buf_min,
 218                             unsigned long buf_max, bool top_down,
 219                             unsigned long *load_addr);
 220 extern struct page *kimage_alloc_control_pages(struct kimage *image,
 221                                                 unsigned int order);
 222 extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
 223                                 unsigned long max, int top_down,
 224                                 unsigned long *load_addr);
 225 extern int kexec_purgatory_get_set_symbol(struct kimage *image,
 226                                           const char *name, void *buf,
 227                                           unsigned int size, bool get_value);
 228 extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
 229                                              const char *name);
 230 extern void __crash_kexec(struct pt_regs *);
 231 extern void crash_kexec(struct pt_regs *);
 232 int kexec_should_crash(struct task_struct *);
 233 int kexec_crash_loaded(void);
 234 void crash_save_cpu(struct pt_regs *regs, int cpu);
 235 void crash_save_vmcoreinfo(void);
 236 void arch_crash_save_vmcoreinfo(void);
 237 __printf(1, 2)
 238 void vmcoreinfo_append_str(const char *fmt, ...);
 239 phys_addr_t paddr_vmcoreinfo_note(void);
 240
 241 #define VMCOREINFO_OSRELEASE(value) \
 242         vmcoreinfo_append_str("OSRELEASE=%s\n", value)
 243 #define VMCOREINFO_PAGESIZE(value) \
 244         vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
 245 #define VMCOREINFO_SYMBOL(name) \
 246         vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
 247 #define VMCOREINFO_SIZE(name) \
 248         vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 249                               (unsigned long)sizeof(name))
 250 #define VMCOREINFO_STRUCT_SIZE(name) \
 251         vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 252                               (unsigned long)sizeof(struct name))
 253 #define VMCOREINFO_OFFSET(name, field) \
 254         vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
 255                               (unsigned long)offsetof(struct name, field))
 256 #define VMCOREINFO_LENGTH(name, value) \
 257         vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
 258 #define VMCOREINFO_NUMBER(name) \
 259         vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
 260 #define VMCOREINFO_CONFIG(name) \
 261         vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
 262 #define VMCOREINFO_PHYS_BASE(value) \
 263         vmcoreinfo_append_str("PHYS_BASE=%lx\n", (unsigned long)value)
 264 #define VMCOREINFO_PAGE_OFFSET(value) \
 265         vmcoreinfo_append_str("PAGE_OFFSET=%lx\n", (unsigned long)value)
 266 #define VMCOREINFO_VMALLOC_START(value) \
 267         vmcoreinfo_append_str("VMALLOC_START=%lx\n", (unsigned long)value)
 268 #define VMCOREINFO_VMEMMAP_START(value) \
 269         vmcoreinfo_append_str("VMEMMAP_START=%lx\n", (unsigned long)value)
 270
 271 extern struct kimage *kexec_image;
 272 extern struct kimage *kexec_crash_image;
 273 extern int kexec_load_disabled;
 274
 275 #ifndef kexec_flush_icache_page
 276 #define kexec_flush_icache_page(page)
 277 #endif
 278
 279 /* List of defined/legal kexec flags */
 280 #ifndef CONFIG_KEXEC_JUMP
 281 #define KEXEC_FLAGS    KEXEC_ON_CRASH
 282 #else
 283 #define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 284 #endif
 285
 286 /* List of defined/legal kexec file flags */
 287 #define KEXEC_FILE_FLAGS        (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
 288                                  KEXEC_FILE_NO_INITRAMFS)
 289
 290 #define VMCOREINFO_BYTES           (4096)
 291 #define VMCOREINFO_NOTE_NAME       "VMCOREINFO"
 292 #define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
 293 #define VMCOREINFO_NOTE_SIZE       (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
 294                                     + VMCOREINFO_NOTE_NAME_BYTES)
 295
 296 /* Location of a reserved region to hold the crash kernel.
 297  */
 298 extern struct resource crashk_res;
 299 extern struct resource crashk_low_res;
 300 typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
 301 extern note_buf_t __percpu *crash_notes;
 302 extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
 303 extern size_t vmcoreinfo_size;
 304 extern size_t vmcoreinfo_max_size;
 305
 306 /* flag to track if kexec reboot is in progress */
 307 extern bool kexec_in_progress;
 308
 309 int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 310                 unsigned long long *crash_size, unsigned long long *crash_base);
 311 int parse_crashkernel_high(char *cmdline, unsigned long long system_ram,
 312                 unsigned long long *crash_size, unsigned long long *crash_base);
 313 int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
 314                 unsigned long long *crash_size, unsigned long long *crash_base);
 315 int crash_shrink_memory(unsigned long new_size);
 316 size_t crash_get_memory_size(void);
 317 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 318
 319 int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
 320                                          unsigned long buf_len);
 321 void * __weak arch_kexec_kernel_image_load(struct kimage *image);
 322 int __weak arch_kimage_file_post_load_cleanup(struct kimage *image);
 323 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 324                                         unsigned long buf_len);
 325 int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
 326                                         Elf_Shdr *sechdrs, unsigned int relsec);
 327 int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 328                                         unsigned int relsec);
 329 void arch_kexec_protect_crashkres(void);
 330 void arch_kexec_unprotect_crashkres(void);
 331
 332 #ifndef page_to_boot_pfn
 333 static inline unsigned long page_to_boot_pfn(struct page *page)
 334 {
 335         return page_to_pfn(page);
 336 }
 337 #endif
 338
 339 #ifndef boot_pfn_to_page
 340 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
 341 {
 342         return pfn_to_page(boot_pfn);
 343 }
 344 #endif
 345
 346 #ifndef phys_to_boot_phys
 347 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
 348 {
 349         return phys;
 350 }
 351 #endif
 352
 353 #ifndef boot_phys_to_phys
 354 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
 355 {
 356         return boot_phys;
 357 }
 358 #endif
 359
 360 static inline unsigned long virt_to_boot_phys(void *addr)
 361 {
 362         return phys_to_boot_phys(__pa((unsigned long)addr));
 363 }
 364
 365 static inline void *boot_phys_to_virt(unsigned long entry)
 366 {
 367         return phys_to_virt(boot_phys_to_phys(entry));
 368 }
 369
 370 #else /* !CONFIG_KEXEC_CORE */
 371 struct pt_regs;
 372 struct task_struct;
 373 static inline void __crash_kexec(struct pt_regs *regs) { }
 374 static inline void crash_kexec(struct pt_regs *regs) { }
 375 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 376 static inline int kexec_crash_loaded(void) { return 0; }
 377 #define kexec_in_progress false
 378 #endif /* CONFIG_KEXEC_CORE */
 379
 380 #endif /* !defined(__ASSEBMLY__) */
 381
 382 #endif /* LINUX_KEXEC_H */