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 <linux/crash_core.h>
  18 #include <asm/io.h>
  19
  20 #include <uapi/linux/kexec.h>
  21
  22 #ifdef CONFIG_KEXEC_CORE
  23 #include <linux/list.h>
  24 #include <linux/compat.h>
  25 #include <linux/ioport.h>
  26 #include <linux/module.h>
  27 #include <asm/kexec.h>
  28
  29 /* Verify architecture specific macros are defined */
  30
  31 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
  32 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
  33 #endif
  34
  35 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
  36 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
  37 #endif
  38
  39 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
  40 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
  41 #endif
  42
  43 #ifndef KEXEC_CONTROL_MEMORY_GFP
  44 #define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
  45 #endif
  46
  47 #ifndef KEXEC_CONTROL_PAGE_SIZE
  48 #error KEXEC_CONTROL_PAGE_SIZE not defined
  49 #endif
  50
  51 #ifndef KEXEC_ARCH
  52 #error KEXEC_ARCH not defined
  53 #endif
  54
  55 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
  56 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
  57 #endif
  58
  59 #ifndef KEXEC_CRASH_MEM_ALIGN
  60 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
  61 #endif
  62
  63 #define KEXEC_CORE_NOTE_NAME    CRASH_CORE_NOTE_NAME
  64
  65 /*
  66  * This structure is used to hold the arguments that are used when loading
  67  * kernel binaries.
  68  */
  69
  70 typedef unsigned long kimage_entry_t;
  71
  72 struct kexec_segment {
  73         /*
  74          * This pointer can point to user memory if kexec_load() system
  75          * call is used or will point to kernel memory if
  76          * kexec_file_load() system call is used.
  77          *
  78          * Use ->buf when expecting to deal with user memory and use ->kbuf
  79          * when expecting to deal with kernel memory.
  80          */
  81         union {
  82                 void __user *buf;
  83                 void *kbuf;
  84         };
  85         size_t bufsz;
  86         unsigned long mem;
  87         size_t memsz;
  88 };
  89
  90 #ifdef CONFIG_COMPAT
  91 struct compat_kexec_segment {
  92         compat_uptr_t buf;
  93         compat_size_t bufsz;
  94         compat_ulong_t mem;     /* User space sees this as a (void *) ... */
  95         compat_size_t memsz;
  96 };
  97 #endif
  98
  99 #ifdef CONFIG_KEXEC_FILE
 100 struct purgatory_info {
 101         /* Pointer to elf header of read only purgatory */
 102         Elf_Ehdr *ehdr;
 103
 104         /* Pointer to purgatory sechdrs which are modifiable */
 105         Elf_Shdr *sechdrs;
 106         /*
 107          * Temporary buffer location where purgatory is loaded and relocated
 108          * This memory can be freed post image load
 109          */
 110         void *purgatory_buf;
 111
 112         /* Address where purgatory is finally loaded and is executed from */
 113         unsigned long purgatory_load_addr;
 114 };
 115
 116 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
 117 typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
 118                              unsigned long kernel_len, char *initrd,
 119                              unsigned long initrd_len, char *cmdline,
 120                              unsigned long cmdline_len);
 121 typedef int (kexec_cleanup_t)(void *loader_data);
 122
 123 #ifdef CONFIG_KEXEC_VERIFY_SIG
 124 typedef int (kexec_verify_sig_t)(const char *kernel_buf,
 125                                  unsigned long kernel_len);
 126 #endif
 127
 128 struct kexec_file_ops {
 129         kexec_probe_t *probe;
 130         kexec_load_t *load;
 131         kexec_cleanup_t *cleanup;
 132 #ifdef CONFIG_KEXEC_VERIFY_SIG
 133         kexec_verify_sig_t *verify_sig;
 134 #endif
 135 };
 136
 137 /**
 138  * struct kexec_buf - parameters for finding a place for a buffer in memory
 139  * @image:      kexec image in which memory to search.
 140  * @buffer:     Contents which will be copied to the allocated memory.
 141  * @bufsz:      Size of @buffer.
 142  * @mem:        On return will have address of the buffer in memory.
 143  * @memsz:      Size for the buffer in memory.
 144  * @buf_align:  Minimum alignment needed.
 145  * @buf_min:    The buffer can't be placed below this address.
 146  * @buf_max:    The buffer can't be placed above this address.
 147  * @top_down:   Allocate from top of memory.
 148  */
 149 struct kexec_buf {
 150         struct kimage *image;
 151         void *buffer;
 152         unsigned long bufsz;
 153         unsigned long mem;
 154         unsigned long memsz;
 155         unsigned long buf_align;
 156         unsigned long buf_min;
 157         unsigned long buf_max;
 158         bool top_down;
 159 };
 160
 161 int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
 162                                int (*func)(u64, u64, void *));
 163 extern int kexec_add_buffer(struct kexec_buf *kbuf);
 164 int kexec_locate_mem_hole(struct kexec_buf *kbuf);
 165 #endif /* CONFIG_KEXEC_FILE */
 166
 167 struct kimage {
 168         kimage_entry_t head;
 169         kimage_entry_t *entry;
 170         kimage_entry_t *last_entry;
 171
 172         unsigned long start;
 173         struct page *control_code_page;
 174         struct page *swap_page;
 175
 176         unsigned long nr_segments;
 177         struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 178
 179         struct list_head control_pages;
 180         struct list_head dest_pages;
 181         struct list_head unusable_pages;
 182
 183         /* Address of next control page to allocate for crash kernels. */
 184         unsigned long control_page;
 185
 186         /* Flags to indicate special processing */
 187         unsigned int type : 1;
 188 #define KEXEC_TYPE_DEFAULT 0
 189 #define KEXEC_TYPE_CRASH   1
 190         unsigned int preserve_context : 1;
 191         /* If set, we are using file mode kexec syscall */
 192         unsigned int file_mode:1;
 193
 194 #ifdef ARCH_HAS_KIMAGE_ARCH
 195         struct kimage_arch arch;
 196 #endif
 197
 198 #ifdef CONFIG_KEXEC_FILE
 199         /* Additional fields for file based kexec syscall */
 200         void *kernel_buf;
 201         unsigned long kernel_buf_len;
 202
 203         void *initrd_buf;
 204         unsigned long initrd_buf_len;
 205
 206         char *cmdline_buf;
 207         unsigned long cmdline_buf_len;
 208
 209         /* File operations provided by image loader */
 210         struct kexec_file_ops *fops;
 211
 212         /* Image loader handling the kernel can store a pointer here */
 213         void *image_loader_data;
 214
 215         /* Information for loading purgatory */
 216         struct purgatory_info purgatory_info;
 217 #endif
 218 };
 219
 220 /* kexec interface functions */
 221 extern void machine_kexec(struct kimage *image);
 222 extern int machine_kexec_prepare(struct kimage *image);
 223 extern void machine_kexec_cleanup(struct kimage *image);
 224 extern asmlinkage long sys_kexec_load(unsigned long entry,
 225                                         unsigned long nr_segments,
 226                                         struct kexec_segment __user *segments,
 227                                         unsigned long flags);
 228 extern int kernel_kexec(void);
 229 extern struct page *kimage_alloc_control_pages(struct kimage *image,
 230                                                 unsigned int order);
 231 extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
 232                                 unsigned long max, int top_down,
 233                                 unsigned long *load_addr);
 234 extern int kexec_purgatory_get_set_symbol(struct kimage *image,
 235                                           const char *name, void *buf,
 236                                           unsigned int size, bool get_value);
 237 extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
 238                                              const char *name);
 239 extern void __crash_kexec(struct pt_regs *);
 240 extern void crash_kexec(struct pt_regs *);
 241 int kexec_should_crash(struct task_struct *);
 242 int kexec_crash_loaded(void);
 243 void crash_save_cpu(struct pt_regs *regs, int cpu);
 244
 245 extern struct kimage *kexec_image;
 246 extern struct kimage *kexec_crash_image;
 247 extern int kexec_load_disabled;
 248
 249 #ifndef kexec_flush_icache_page
 250 #define kexec_flush_icache_page(page)
 251 #endif
 252
 253 /* List of defined/legal kexec flags */
 254 #ifndef CONFIG_KEXEC_JUMP
 255 #define KEXEC_FLAGS    KEXEC_ON_CRASH
 256 #else
 257 #define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 258 #endif
 259
 260 /* List of defined/legal kexec file flags */
 261 #define KEXEC_FILE_FLAGS        (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
 262                                  KEXEC_FILE_NO_INITRAMFS)
 263
 264 /* Location of a reserved region to hold the crash kernel.
 265  */
 266 extern struct resource crashk_res;
 267 extern struct resource crashk_low_res;
 268 extern note_buf_t __percpu *crash_notes;
 269
 270 /* flag to track if kexec reboot is in progress */
 271 extern bool kexec_in_progress;
 272
 273 int crash_shrink_memory(unsigned long new_size);
 274 size_t crash_get_memory_size(void);
 275 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 276
 277 int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
 278                                          unsigned long buf_len);
 279 void * __weak arch_kexec_kernel_image_load(struct kimage *image);
 280 int __weak arch_kimage_file_post_load_cleanup(struct kimage *image);
 281 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 282                                         unsigned long buf_len);
 283 int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
 284                                         Elf_Shdr *sechdrs, unsigned int relsec);
 285 int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 286                                         unsigned int relsec);
 287 void arch_kexec_protect_crashkres(void);
 288 void arch_kexec_unprotect_crashkres(void);
 289
 290 #ifndef page_to_boot_pfn
 291 static inline unsigned long page_to_boot_pfn(struct page *page)
 292 {
 293         return page_to_pfn(page);
 294 }
 295 #endif
 296
 297 #ifndef boot_pfn_to_page
 298 static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
 299 {
 300         return pfn_to_page(boot_pfn);
 301 }
 302 #endif
 303
 304 #ifndef phys_to_boot_phys
 305 static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
 306 {
 307         return phys;
 308 }
 309 #endif
 310
 311 #ifndef boot_phys_to_phys
 312 static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
 313 {
 314         return boot_phys;
 315 }
 316 #endif
 317
 318 static inline unsigned long virt_to_boot_phys(void *addr)
 319 {
 320         return phys_to_boot_phys(__pa((unsigned long)addr));
 321 }
 322
 323 static inline void *boot_phys_to_virt(unsigned long entry)
 324 {
 325         return phys_to_virt(boot_phys_to_phys(entry));
 326 }
 327
 328 #else /* !CONFIG_KEXEC_CORE */
 329 struct pt_regs;
 330 struct task_struct;
 331 static inline void __crash_kexec(struct pt_regs *regs) { }
 332 static inline void crash_kexec(struct pt_regs *regs) { }
 333 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 334 static inline int kexec_crash_loaded(void) { return 0; }
 335 #define kexec_in_progress false
 336 #endif /* CONFIG_KEXEC_CORE */
 337
 338 #endif /* !defined(__ASSEBMLY__) */
 339
 340 #endif /* LINUX_KEXEC_H */