Linux Kernel  3.7.1
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kexec.h
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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 <asm/kexec.h>
14 
15 /* Verify architecture specific macros are defined */
16 
17 #ifndef KEXEC_SOURCE_MEMORY_LIMIT
18 #error KEXEC_SOURCE_MEMORY_LIMIT not defined
19 #endif
20 
21 #ifndef KEXEC_DESTINATION_MEMORY_LIMIT
22 #error KEXEC_DESTINATION_MEMORY_LIMIT not defined
23 #endif
24 
25 #ifndef KEXEC_CONTROL_MEMORY_LIMIT
26 #error KEXEC_CONTROL_MEMORY_LIMIT not defined
27 #endif
28 
29 #ifndef KEXEC_CONTROL_PAGE_SIZE
30 #error KEXEC_CONTROL_PAGE_SIZE not defined
31 #endif
32 
33 #ifndef KEXEC_ARCH
34 #error KEXEC_ARCH not defined
35 #endif
36 
37 #ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
38 #define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
39 #endif
40 
41 #ifndef KEXEC_CRASH_MEM_ALIGN
42 #define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
43 #endif
44 
45 #define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
46 #define KEXEC_CORE_NOTE_NAME "CORE"
47 #define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
48 #define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
49 /*
50  * The per-cpu notes area is a list of notes terminated by a "NULL"
51  * note header. For kdump, the code in vmcore.c runs in the context
52  * of the second kernel to combine them into one note.
53  */
54 #ifndef KEXEC_NOTE_BYTES
55 #define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) + \
56  KEXEC_CORE_NOTE_NAME_BYTES + \
57  KEXEC_CORE_NOTE_DESC_BYTES )
58 #endif
59 
60 /*
61  * This structure is used to hold the arguments that are used when loading
62  * kernel binaries.
63  */
64 
65 typedef unsigned long kimage_entry_t;
66 #define IND_DESTINATION 0x1
67 #define IND_INDIRECTION 0x2
68 #define IND_DONE 0x4
69 #define IND_SOURCE 0x8
70 
71 struct kexec_segment {
72  void __user *buf;
73  size_t bufsz;
74  unsigned long mem;
75  size_t memsz;
76 };
77 
78 #ifdef CONFIG_COMPAT
79 struct compat_kexec_segment {
81  compat_size_t bufsz;
82  compat_ulong_t mem; /* User space sees this as a (void *) ... */
83  compat_size_t memsz;
84 };
85 #endif
86 
87 struct kimage {
88  kimage_entry_t head;
89  kimage_entry_t *entry;
90  kimage_entry_t *last_entry;
91 
92  unsigned long destination;
93 
94  unsigned long start;
95  struct page *control_code_page;
96  struct page *swap_page;
97 
98  unsigned long nr_segments;
100 
101  struct list_head control_pages;
102  struct list_head dest_pages;
103  struct list_head unuseable_pages;
104 
105  /* Address of next control page to allocate for crash kernels. */
106  unsigned long control_page;
107 
108  /* Flags to indicate special processing */
109  unsigned int type : 1;
110 #define KEXEC_TYPE_DEFAULT 0
111 #define KEXEC_TYPE_CRASH 1
112  unsigned int preserve_context : 1;
113 
114 #ifdef ARCH_HAS_KIMAGE_ARCH
115  struct kimage_arch arch;
116 #endif
117 };
118 
119 
120 
121 /* kexec interface functions */
122 extern void machine_kexec(struct kimage *image);
123 extern int machine_kexec_prepare(struct kimage *image);
124 extern void machine_kexec_cleanup(struct kimage *image);
125 extern asmlinkage long sys_kexec_load(unsigned long entry,
126  unsigned long nr_segments,
127  struct kexec_segment __user *segments,
128  unsigned long flags);
129 extern int kernel_kexec(void);
130 #ifdef CONFIG_COMPAT
131 extern asmlinkage long compat_sys_kexec_load(unsigned long entry,
132  unsigned long nr_segments,
133  struct compat_kexec_segment __user *segments,
134  unsigned long flags);
135 #endif
136 extern struct page *kimage_alloc_control_pages(struct kimage *image,
137  unsigned int order);
138 extern void crash_kexec(struct pt_regs *);
139 int kexec_should_crash(struct task_struct *);
140 void crash_save_cpu(struct pt_regs *regs, int cpu);
141 void crash_save_vmcoreinfo(void);
142 void crash_map_reserved_pages(void);
143 void crash_unmap_reserved_pages(void);
144 void arch_crash_save_vmcoreinfo(void);
145 __printf(1, 2)
146 void vmcoreinfo_append_str(const char *fmt, ...);
147 unsigned long paddr_vmcoreinfo_note(void);
148 
149 #define VMCOREINFO_OSRELEASE(value) \
150  vmcoreinfo_append_str("OSRELEASE=%s\n", value)
151 #define VMCOREINFO_PAGESIZE(value) \
152  vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
153 #define VMCOREINFO_SYMBOL(name) \
154  vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
155 #define VMCOREINFO_SIZE(name) \
156  vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
157  (unsigned long)sizeof(name))
158 #define VMCOREINFO_STRUCT_SIZE(name) \
159  vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
160  (unsigned long)sizeof(struct name))
161 #define VMCOREINFO_OFFSET(name, field) \
162  vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
163  (unsigned long)offsetof(struct name, field))
164 #define VMCOREINFO_LENGTH(name, value) \
165  vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
166 #define VMCOREINFO_NUMBER(name) \
167  vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
168 #define VMCOREINFO_CONFIG(name) \
169  vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
170 
171 extern struct kimage *kexec_image;
172 extern struct kimage *kexec_crash_image;
173 
174 #ifndef kexec_flush_icache_page
175 #define kexec_flush_icache_page(page)
176 #endif
177 
178 /* List of defined/legal kexec flags */
179 #ifndef CONFIG_KEXEC_JUMP
180 #define KEXEC_FLAGS KEXEC_ON_CRASH
181 #else
182 #define KEXEC_FLAGS (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
183 #endif
184 
185 #define VMCOREINFO_BYTES (4096)
186 #define VMCOREINFO_NOTE_NAME "VMCOREINFO"
187 #define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
188 #define VMCOREINFO_NOTE_SIZE (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
189  + VMCOREINFO_NOTE_NAME_BYTES)
190 
191 /* Location of a reserved region to hold the crash kernel.
192  */
193 extern struct resource crashk_res;
194 typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
195 extern note_buf_t __percpu *crash_notes;
196 extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
197 extern size_t vmcoreinfo_size;
198 extern size_t vmcoreinfo_max_size;
199 
200 int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
201  unsigned long long *crash_size, unsigned long long *crash_base);
202 int crash_shrink_memory(unsigned long new_size);
203 size_t crash_get_memory_size(void);
204 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
205 
206 #else /* !CONFIG_KEXEC */
207 struct pt_regs;
208 struct task_struct;
209 static inline void crash_kexec(struct pt_regs *regs) { }
210 static inline int kexec_should_crash(struct task_struct *p) { return 0; }
211 #endif /* CONFIG_KEXEC */
212 #endif /* LINUX_KEXEC_H */