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