include/linux/kexec.h

   1 #ifndef LINUX_KEXEC_H
   2 #define LINUX_KEXEC_H
   3
   4 /* kexec system call -  It loads the new kernel to boot into.
   5  * kexec does not sync, or unmount filesystems so if you need
   6  * that to happen you need to do that yourself.
   7  */
   8
   9 #include <linux/types.h>
  10
  11 /* kexec flags for different usage scenarios */
  12 #define KEXEC_ON_CRASH          0x00000001
  13 #define KEXEC_PRESERVE_CONTEXT  0x00000002
  14 #define KEXEC_ARCH_MASK         0xffff0000
  15
  16 /* These values match the ELF architecture values.
  17  * Unless there is a good reason that should continue to be the case.
  18  */
  19 #define KEXEC_ARCH_DEFAULT ( 0 << 16)
  20 #define KEXEC_ARCH_386     ( 3 << 16)
  21 #define KEXEC_ARCH_X86_64  (62 << 16)
  22 #define KEXEC_ARCH_PPC     (20 << 16)
  23 #define KEXEC_ARCH_PPC64   (21 << 16)
  24 #define KEXEC_ARCH_IA_64   (50 << 16)
  25 #define KEXEC_ARCH_ARM     (40 << 16)
  26 #define KEXEC_ARCH_S390    (22 << 16)
  27 #define KEXEC_ARCH_SH      (42 << 16)
  28 #define KEXEC_ARCH_MIPS_LE (10 << 16)
  29 #define KEXEC_ARCH_MIPS    ( 8 << 16)
  30
  31 /* The artificial cap on the number of segments passed to kexec_load. */
  32 #define KEXEC_SEGMENT_MAX 16
  33
  34 #ifndef __KERNEL__
  35 /*
  36  * This structure is used to hold the arguments that are used when
  37  * loading  kernel binaries.
  38  */
  39 struct kexec_segment {
  40         const void *buf;
  41         size_t bufsz;
  42         const void *mem;
  43         size_t memsz;
  44 };
  45
  46 /* Load a new kernel image as described by the kexec_segment array
  47  * consisting of passed number of segments at the entry-point address.
  48  * The flags allow different useage types.
  49  */
  50 extern int kexec_load(void *, size_t, struct kexec_segment *,
  51                 unsigned long int);
  52 #endif /* __KERNEL__ */
  53
  54 #ifdef __KERNEL__
  55 #ifdef CONFIG_KEXEC
  56 #include <linux/list.h>
  57 #include <linux/linkage.h>
  58 #include <linux/compat.h>
  59 #include <linux/ioport.h>
  60 #include <linux/elfcore.h>
  61 #include <linux/elf.h>
  62 #include <asm/kexec.h>
  63
  64 /* Verify architecture specific macros are defined */
  65
  66 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
  67 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
  68 #endif
  69
  70 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
  71 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
  72 #endif
  73
  74 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
  75 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
  76 #endif
  77
  78 #ifndef KEXEC_CONTROL_PAGE_SIZE
  79 #error KEXEC_CONTROL_PAGE_SIZE not defined
  80 #endif
  81
  82 #ifndef KEXEC_ARCH
  83 #error KEXEC_ARCH not defined
  84 #endif
  85
  86 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
  87 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
  88 #endif
  89
  90 #ifndef KEXEC_CRASH_MEM_ALIGN
  91 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
  92 #endif
  93
  94 #define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
  95 #define KEXEC_CORE_NOTE_NAME "CORE"
  96 #define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
  97 #define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
  98 /*
  99  * The per-cpu notes area is a list of notes terminated by a "NULL"
 100  * note header.  For kdump, the code in vmcore.c runs in the context
 101  * of the second kernel to combine them into one note.
 102  */
 103 #ifndef KEXEC_NOTE_BYTES
 104 #define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) +                \
 105                             KEXEC_CORE_NOTE_NAME_BYTES +                \
 106                             KEXEC_CORE_NOTE_DESC_BYTES )
 107 #endif
 108
 109 /*
 110  * This structure is used to hold the arguments that are used when loading
 111  * kernel binaries.
 112  */
 113
 114 typedef unsigned long kimage_entry_t;
 115 #define IND_DESTINATION  0x1
 116 #define IND_INDIRECTION  0x2
 117 #define IND_DONE         0x4
 118 #define IND_SOURCE       0x8
 119
 120 struct kexec_segment {
 121         void __user *buf;
 122         size_t bufsz;
 123         unsigned long mem;
 124         size_t memsz;
 125 };
 126
 127 #ifdef CONFIG_COMPAT
 128 struct compat_kexec_segment {
 129         compat_uptr_t buf;
 130         compat_size_t bufsz;
 131         compat_ulong_t mem;     /* User space sees this as a (void *) ... */
 132         compat_size_t memsz;
 133 };
 134 #endif
 135
 136 struct kimage {
 137         kimage_entry_t head;
 138         kimage_entry_t *entry;
 139         kimage_entry_t *last_entry;
 140
 141         unsigned long destination;
 142
 143         unsigned long start;
 144         struct page *control_code_page;
 145         struct page *swap_page;
 146
 147         unsigned long nr_segments;
 148         struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 149
 150         struct list_head control_pages;
 151         struct list_head dest_pages;
 152         struct list_head unuseable_pages;
 153
 154         /* Address of next control page to allocate for crash kernels. */
 155         unsigned long control_page;
 156
 157         /* Flags to indicate special processing */
 158         unsigned int type : 1;
 159 #define KEXEC_TYPE_DEFAULT 0
 160 #define KEXEC_TYPE_CRASH   1
 161         unsigned int preserve_context : 1;
 162
 163 #ifdef ARCH_HAS_KIMAGE_ARCH
 164         struct kimage_arch arch;
 165 #endif
 166 };
 167
 168
 169
 170 /* kexec interface functions */
 171 extern void machine_kexec(struct kimage *image);
 172 extern int machine_kexec_prepare(struct kimage *image);
 173 extern void machine_kexec_cleanup(struct kimage *image);
 174 extern asmlinkage long sys_kexec_load(unsigned long entry,
 175                                         unsigned long nr_segments,
 176                                         struct kexec_segment __user *segments,
 177                                         unsigned long flags);
 178 extern int kernel_kexec(void);
 179 #ifdef CONFIG_COMPAT
 180 extern asmlinkage long compat_sys_kexec_load(unsigned long entry,
 181                                 unsigned long nr_segments,
 182                                 struct compat_kexec_segment __user *segments,
 183                                 unsigned long flags);
 184 #endif
 185 extern struct page *kimage_alloc_control_pages(struct kimage *image,
 186                                                 unsigned int order);
 187 extern void crash_kexec(struct pt_regs *);
 188 int kexec_should_crash(struct task_struct *);
 189 void crash_save_cpu(struct pt_regs *regs, int cpu);
 190 void crash_save_vmcoreinfo(void);
 191 void crash_map_reserved_pages(void);
 192 void crash_unmap_reserved_pages(void);
 193 void arch_crash_save_vmcoreinfo(void);
 194 __printf(1, 2)
 195 void vmcoreinfo_append_str(const char *fmt, ...);
 196 unsigned long paddr_vmcoreinfo_note(void);
 197
 198 #define VMCOREINFO_OSRELEASE(value) \
 199         vmcoreinfo_append_str("OSRELEASE=%s\n", value)
 200 #define VMCOREINFO_PAGESIZE(value) \
 201         vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
 202 #define VMCOREINFO_SYMBOL(name) \
 203         vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
 204 #define VMCOREINFO_SIZE(name) \
 205         vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 206                               (unsigned long)sizeof(name))
 207 #define VMCOREINFO_STRUCT_SIZE(name) \
 208         vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 209                               (unsigned long)sizeof(struct name))
 210 #define VMCOREINFO_OFFSET(name, field) \
 211         vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
 212                               (unsigned long)offsetof(struct name, field))
 213 #define VMCOREINFO_LENGTH(name, value) \
 214         vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
 215 #define VMCOREINFO_NUMBER(name) \
 216         vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
 217 #define VMCOREINFO_CONFIG(name) \
 218         vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
 219
 220 extern struct kimage *kexec_image;
 221 extern struct kimage *kexec_crash_image;
 222
 223 #ifndef kexec_flush_icache_page
 224 #define kexec_flush_icache_page(page)
 225 #endif
 226
 227 /* List of defined/legal kexec flags */
 228 #ifndef CONFIG_KEXEC_JUMP
 229 #define KEXEC_FLAGS    KEXEC_ON_CRASH
 230 #else
 231 #define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 232 #endif
 233
 234 #define VMCOREINFO_BYTES           (4096)
 235 #define VMCOREINFO_NOTE_NAME       "VMCOREINFO"
 236 #define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
 237 #define VMCOREINFO_NOTE_SIZE       (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
 238                                     + VMCOREINFO_NOTE_NAME_BYTES)
 239
 240 /* Location of a reserved region to hold the crash kernel.
 241  */
 242 extern struct resource crashk_res;
 243 typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
 244 extern note_buf_t __percpu *crash_notes;
 245 extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
 246 extern size_t vmcoreinfo_size;
 247 extern size_t vmcoreinfo_max_size;
 248
 249 int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 250                 unsigned long long *crash_size, unsigned long long *crash_base);
 251 int crash_shrink_memory(unsigned long new_size);
 252 size_t crash_get_memory_size(void);
 253 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 254
 255 #else /* !CONFIG_KEXEC */
 256 struct pt_regs;
 257 struct task_struct;
 258 static inline void crash_kexec(struct pt_regs *regs) { }
 259 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 260 #endif /* CONFIG_KEXEC */
 261 #endif /* __KERNEL__ */
 262 #endif /* LINUX_KEXEC_H */