include/linux/kexec.h

   1 #ifndef LINUX_KEXEC_H
   2 #define LINUX_KEXEC_H
   3
   4 #ifdef CONFIG_KEXEC
   5 #include <linux/types.h>
   6 #include <linux/list.h>
   7 #include <linux/linkage.h>
   8 #include <linux/compat.h>
   9 #include <linux/ioport.h>
  10 #include <asm/kexec.h>
  11
  12 /* Verify architecture specific macros are defined */
  13
  14 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
  15 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
  16 #endif
  17
  18 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
  19 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
  20 #endif
  21
  22 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
  23 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
  24 #endif
  25
  26 #ifndef KEXEC_CONTROL_CODE_SIZE
  27 #error KEXEC_CONTROL_CODE_SIZE not defined
  28 #endif
  29
  30 #ifndef KEXEC_ARCH
  31 #error KEXEC_ARCH not defined
  32 #endif
  33
  34 /*
  35  * This structure is used to hold the arguments that are used when loading
  36  * kernel binaries.
  37  */
  38
  39 typedef unsigned long kimage_entry_t;
  40 #define IND_DESTINATION  0x1
  41 #define IND_INDIRECTION  0x2
  42 #define IND_DONE         0x4
  43 #define IND_SOURCE       0x8
  44
  45 #define KEXEC_SEGMENT_MAX 16
  46 struct kexec_segment {
  47         void __user *buf;
  48         size_t bufsz;
  49         unsigned long mem;      /* User space sees this as a (void *) ... */
  50         size_t memsz;
  51 };
  52
  53 #ifdef CONFIG_COMPAT
  54 struct compat_kexec_segment {
  55         compat_uptr_t buf;
  56         compat_size_t bufsz;
  57         compat_ulong_t mem;     /* User space sees this as a (void *) ... */
  58         compat_size_t memsz;
  59 };
  60 #endif
  61
  62 struct kimage {
  63         kimage_entry_t head;
  64         kimage_entry_t *entry;
  65         kimage_entry_t *last_entry;
  66
  67         unsigned long destination;
  68
  69         unsigned long start;
  70         struct page *control_code_page;
  71
  72         unsigned long nr_segments;
  73         struct kexec_segment segment[KEXEC_SEGMENT_MAX];
  74
  75         struct list_head control_pages;
  76         struct list_head dest_pages;
  77         struct list_head unuseable_pages;
  78
  79         /* Address of next control page to allocate for crash kernels. */
  80         unsigned long control_page;
  81
  82         /* Flags to indicate special processing */
  83         unsigned int type : 1;
  84 #define KEXEC_TYPE_DEFAULT 0
  85 #define KEXEC_TYPE_CRASH   1
  86 };
  87
  88
  89
  90 /* kexec interface functions */
  91 extern NORET_TYPE void machine_kexec(struct kimage *image) ATTRIB_NORET;
  92 extern int machine_kexec_prepare(struct kimage *image);
  93 extern void machine_kexec_cleanup(struct kimage *image);
  94 extern asmlinkage long sys_kexec_load(unsigned long entry,
  95                                         unsigned long nr_segments,
  96                                         struct kexec_segment __user *segments,
  97                                         unsigned long flags);
  98 #ifdef CONFIG_COMPAT
  99 extern asmlinkage long compat_sys_kexec_load(unsigned long entry,
 100                                 unsigned long nr_segments,
 101                                 struct compat_kexec_segment __user *segments,
 102                                 unsigned long flags);
 103 #endif
 104 extern struct page *kimage_alloc_control_pages(struct kimage *image,
 105                                                 unsigned int order);
 106 extern void crash_kexec(struct pt_regs *);
 107 int kexec_should_crash(struct task_struct *);
 108 extern struct kimage *kexec_image;
 109 extern struct kimage *kexec_crash_image;
 110
 111 #define KEXEC_ON_CRASH  0x00000001
 112 #define KEXEC_ARCH_MASK 0xffff0000
 113
 114 /* These values match the ELF architecture values.
 115  * Unless there is a good reason that should continue to be the case.
 116  */
 117 #define KEXEC_ARCH_DEFAULT ( 0 << 16)
 118 #define KEXEC_ARCH_386     ( 3 << 16)
 119 #define KEXEC_ARCH_X86_64  (62 << 16)
 120 #define KEXEC_ARCH_PPC     (20 << 16)
 121 #define KEXEC_ARCH_PPC64   (21 << 16)
 122 #define KEXEC_ARCH_IA_64   (50 << 16)
 123 #define KEXEC_ARCH_S390    (22 << 16)
 124 #define KEXEC_ARCH_SH      (42 << 16)
 125
 126 #define KEXEC_FLAGS    (KEXEC_ON_CRASH)  /* List of defined/legal kexec flags */
 127
 128 /* Location of a reserved region to hold the crash kernel.
 129  */
 130 extern struct resource crashk_res;
 131 typedef u32 note_buf_t[MAX_NOTE_BYTES/4];
 132 extern note_buf_t *crash_notes;
 133
 134 #else /* !CONFIG_KEXEC */
 135 struct pt_regs;
 136 struct task_struct;
 137 static inline void crash_kexec(struct pt_regs *regs) { }
 138 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 139 #endif /* CONFIG_KEXEC */
 140 #endif /* LINUX_KEXEC_H */