include/linux/kexec.h

   1 #ifndef LINUX_KEXEC_H
   2 #define LINUX_KEXEC_H
   3
   4 #include <uapi/linux/kexec.h>
   5
   6 #ifdef CONFIG_KEXEC
   7 #include <linux/list.h>
   8 #include <linux/linkage.h>
   9 #include <linux/compat.h>
  10 #include <linux/ioport.h>
  11 #include <linux/elfcore.h>
  12 #include <linux/elf.h>
  13 #include <linux/module.h>
  14 #include <asm/kexec.h>
  15
  16 /* Verify architecture specific macros are defined */
  17
  18 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
  19 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
  20 #endif
  21
  22 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
  23 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
  24 #endif
  25
  26 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
  27 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
  28 #endif
  29
  30 #ifndef KEXEC_CONTROL_PAGE_SIZE
  31 #error KEXEC_CONTROL_PAGE_SIZE not defined
  32 #endif
  33
  34 #ifndef KEXEC_ARCH
  35 #error KEXEC_ARCH not defined
  36 #endif
  37
  38 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
  39 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
  40 #endif
  41
  42 #ifndef KEXEC_CRASH_MEM_ALIGN
  43 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
  44 #endif
  45
  46 #define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
  47 #define KEXEC_CORE_NOTE_NAME "CORE"
  48 #define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
  49 #define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
  50 /*
  51  * The per-cpu notes area is a list of notes terminated by a "NULL"
  52  * note header.  For kdump, the code in vmcore.c runs in the context
  53  * of the second kernel to combine them into one note.
  54  */
  55 #ifndef KEXEC_NOTE_BYTES
  56 #define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) +                \
  57                             KEXEC_CORE_NOTE_NAME_BYTES +                \
  58                             KEXEC_CORE_NOTE_DESC_BYTES )
  59 #endif
  60
  61 /*
  62  * This structure is used to hold the arguments that are used when loading
  63  * kernel binaries.
  64  */
  65
  66 typedef unsigned long kimage_entry_t;
  67 #define IND_DESTINATION  0x1
  68 #define IND_INDIRECTION  0x2
  69 #define IND_DONE         0x4
  70 #define IND_SOURCE       0x8
  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 struct kexec_sha_region {
 100         unsigned long start;
 101         unsigned long len;
 102 };
 103
 104 struct purgatory_info {
 105         /* Pointer to elf header of read only purgatory */
 106         Elf_Ehdr *ehdr;
 107
 108         /* Pointer to purgatory sechdrs which are modifiable */
 109         Elf_Shdr *sechdrs;
 110         /*
 111          * Temporary buffer location where purgatory is loaded and relocated
 112          * This memory can be freed post image load
 113          */
 114         void *purgatory_buf;
 115
 116         /* Address where purgatory is finally loaded and is executed from */
 117         unsigned long purgatory_load_addr;
 118 };
 119
 120 struct kimage {
 121         kimage_entry_t head;
 122         kimage_entry_t *entry;
 123         kimage_entry_t *last_entry;
 124
 125         unsigned long destination;
 126
 127         unsigned long start;
 128         struct page *control_code_page;
 129         struct page *swap_page;
 130
 131         unsigned long nr_segments;
 132         struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 133
 134         struct list_head control_pages;
 135         struct list_head dest_pages;
 136         struct list_head unusable_pages;
 137
 138         /* Address of next control page to allocate for crash kernels. */
 139         unsigned long control_page;
 140
 141         /* Flags to indicate special processing */
 142         unsigned int type : 1;
 143 #define KEXEC_TYPE_DEFAULT 0
 144 #define KEXEC_TYPE_CRASH   1
 145         unsigned int preserve_context : 1;
 146         /* If set, we are using file mode kexec syscall */
 147         unsigned int file_mode:1;
 148
 149 #ifdef ARCH_HAS_KIMAGE_ARCH
 150         struct kimage_arch arch;
 151 #endif
 152
 153         /* Additional fields for file based kexec syscall */
 154         void *kernel_buf;
 155         unsigned long kernel_buf_len;
 156
 157         void *initrd_buf;
 158         unsigned long initrd_buf_len;
 159
 160         char *cmdline_buf;
 161         unsigned long cmdline_buf_len;
 162
 163         /* File operations provided by image loader */
 164         struct kexec_file_ops *fops;
 165
 166         /* Image loader handling the kernel can store a pointer here */
 167         void *image_loader_data;
 168
 169         /* Information for loading purgatory */
 170         struct purgatory_info purgatory_info;
 171 };
 172
 173 /*
 174  * Keeps track of buffer parameters as provided by caller for requesting
 175  * memory placement of buffer.
 176  */
 177 struct kexec_buf {
 178         struct kimage *image;
 179         char *buffer;
 180         unsigned long bufsz;
 181         unsigned long mem;
 182         unsigned long memsz;
 183         unsigned long buf_align;
 184         unsigned long buf_min;
 185         unsigned long buf_max;
 186         bool top_down;          /* allocate from top of memory hole */
 187 };
 188
 189 typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
 190 typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
 191                              unsigned long kernel_len, char *initrd,
 192                              unsigned long initrd_len, char *cmdline,
 193                              unsigned long cmdline_len);
 194 typedef int (kexec_cleanup_t)(void *loader_data);
 195 typedef int (kexec_verify_sig_t)(const char *kernel_buf,
 196                                  unsigned long kernel_len);
 197
 198 struct kexec_file_ops {
 199         kexec_probe_t *probe;
 200         kexec_load_t *load;
 201         kexec_cleanup_t *cleanup;
 202         kexec_verify_sig_t *verify_sig;
 203 };
 204
 205 /* kexec interface functions */
 206 extern void machine_kexec(struct kimage *image);
 207 extern int machine_kexec_prepare(struct kimage *image);
 208 extern void machine_kexec_cleanup(struct kimage *image);
 209 extern asmlinkage long sys_kexec_load(unsigned long entry,
 210                                         unsigned long nr_segments,
 211                                         struct kexec_segment __user *segments,
 212                                         unsigned long flags);
 213 extern int kernel_kexec(void);
 214 extern int kexec_add_buffer(struct kimage *image, char *buffer,
 215                             unsigned long bufsz, unsigned long memsz,
 216                             unsigned long buf_align, unsigned long buf_min,
 217                             unsigned long buf_max, bool top_down,
 218                             unsigned long *load_addr);
 219 extern struct page *kimage_alloc_control_pages(struct kimage *image,
 220                                                 unsigned int order);
 221 extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
 222                                 unsigned long max, int top_down,
 223                                 unsigned long *load_addr);
 224 extern int kexec_purgatory_get_set_symbol(struct kimage *image,
 225                                           const char *name, void *buf,
 226                                           unsigned int size, bool get_value);
 227 extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
 228                                              const char *name);
 229 extern void crash_kexec(struct pt_regs *);
 230 int kexec_should_crash(struct task_struct *);
 231 void crash_save_cpu(struct pt_regs *regs, int cpu);
 232 void crash_save_vmcoreinfo(void);
 233 void crash_map_reserved_pages(void);
 234 void crash_unmap_reserved_pages(void);
 235 void arch_crash_save_vmcoreinfo(void);
 236 __printf(1, 2)
 237 void vmcoreinfo_append_str(const char *fmt, ...);
 238 unsigned long paddr_vmcoreinfo_note(void);
 239
 240 #define VMCOREINFO_OSRELEASE(value) \
 241         vmcoreinfo_append_str("OSRELEASE=%s\n", value)
 242 #define VMCOREINFO_PAGESIZE(value) \
 243         vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
 244 #define VMCOREINFO_SYMBOL(name) \
 245         vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
 246 #define VMCOREINFO_SIZE(name) \
 247         vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 248                               (unsigned long)sizeof(name))
 249 #define VMCOREINFO_STRUCT_SIZE(name) \
 250         vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 251                               (unsigned long)sizeof(struct name))
 252 #define VMCOREINFO_OFFSET(name, field) \
 253         vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
 254                               (unsigned long)offsetof(struct name, field))
 255 #define VMCOREINFO_LENGTH(name, value) \
 256         vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
 257 #define VMCOREINFO_NUMBER(name) \
 258         vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
 259 #define VMCOREINFO_CONFIG(name) \
 260         vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
 261
 262 extern struct kimage *kexec_image;
 263 extern struct kimage *kexec_crash_image;
 264 extern int kexec_load_disabled;
 265
 266 #ifndef kexec_flush_icache_page
 267 #define kexec_flush_icache_page(page)
 268 #endif
 269
 270 /* List of defined/legal kexec flags */
 271 #ifndef CONFIG_KEXEC_JUMP
 272 #define KEXEC_FLAGS    KEXEC_ON_CRASH
 273 #else
 274 #define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 275 #endif
 276
 277 /* List of defined/legal kexec file flags */
 278 #define KEXEC_FILE_FLAGS        (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
 279                                  KEXEC_FILE_NO_INITRAMFS)
 280
 281 #define VMCOREINFO_BYTES           (4096)
 282 #define VMCOREINFO_NOTE_NAME       "VMCOREINFO"
 283 #define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
 284 #define VMCOREINFO_NOTE_SIZE       (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
 285                                     + VMCOREINFO_NOTE_NAME_BYTES)
 286
 287 /* Location of a reserved region to hold the crash kernel.
 288  */
 289 extern struct resource crashk_res;
 290 extern struct resource crashk_low_res;
 291 typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
 292 extern note_buf_t __percpu *crash_notes;
 293 extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
 294 extern size_t vmcoreinfo_size;
 295 extern size_t vmcoreinfo_max_size;
 296
 297 /* flag to track if kexec reboot is in progress */
 298 extern bool kexec_in_progress;
 299
 300 int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 301                 unsigned long long *crash_size, unsigned long long *crash_base);
 302 int parse_crashkernel_high(char *cmdline, unsigned long long system_ram,
 303                 unsigned long long *crash_size, unsigned long long *crash_base);
 304 int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
 305                 unsigned long long *crash_size, unsigned long long *crash_base);
 306 int crash_shrink_memory(unsigned long new_size);
 307 size_t crash_get_memory_size(void);
 308 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 309
 310 #else /* !CONFIG_KEXEC */
 311 struct pt_regs;
 312 struct task_struct;
 313 static inline void crash_kexec(struct pt_regs *regs) { }
 314 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 315 #endif /* CONFIG_KEXEC */
 316 #endif /* LINUX_KEXEC_H */