Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
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
66typedef 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
72struct 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
91struct 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
99struct kexec_sha_region {
100 unsigned long start;
101 unsigned long len;
102};
103
104struct 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
120struct 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 */
177struct 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
189typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
190typedef 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);
194typedef int (kexec_cleanup_t)(void *loader_data);
195typedef int (kexec_verify_sig_t)(const char *kernel_buf,
196 unsigned long kernel_len);
197
198struct 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 */
206extern void machine_kexec(struct kimage *image);
207extern int machine_kexec_prepare(struct kimage *image);
208extern void machine_kexec_cleanup(struct kimage *image);
209extern asmlinkage long sys_kexec_load(unsigned long entry,
210 unsigned long nr_segments,
211 struct kexec_segment __user *segments,
212 unsigned long flags);
213extern int kernel_kexec(void);
214extern 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);
219extern struct page *kimage_alloc_control_pages(struct kimage *image,
220 unsigned int order);
221extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
222 unsigned long max, int top_down,
223 unsigned long *load_addr);
224extern int kexec_purgatory_get_set_symbol(struct kimage *image,
225 const char *name, void *buf,
226 unsigned int size, bool get_value);
227extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
228 const char *name);
229extern void crash_kexec(struct pt_regs *);
230int kexec_should_crash(struct task_struct *);
231void crash_save_cpu(struct pt_regs *regs, int cpu);
232void crash_save_vmcoreinfo(void);
233void crash_map_reserved_pages(void);
234void crash_unmap_reserved_pages(void);
235void arch_crash_save_vmcoreinfo(void);
236__printf(1, 2)
237void vmcoreinfo_append_str(const char *fmt, ...);
238unsigned 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
262extern struct kimage *kexec_image;
263extern struct kimage *kexec_crash_image;
264extern 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 */
289extern struct resource crashk_res;
290extern struct resource crashk_low_res;
291typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
292extern note_buf_t __percpu *crash_notes;
293extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
294extern size_t vmcoreinfo_size;
295extern size_t vmcoreinfo_max_size;
296
297/* flag to track if kexec reboot is in progress */
298extern bool kexec_in_progress;
299
300int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
301 unsigned long long *crash_size, unsigned long long *crash_base);
302int parse_crashkernel_high(char *cmdline, unsigned long long system_ram,
303 unsigned long long *crash_size, unsigned long long *crash_base);
304int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
305 unsigned long long *crash_size, unsigned long long *crash_base);
306int crash_shrink_memory(unsigned long new_size);
307size_t crash_get_memory_size(void);
308void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
309
310#else /* !CONFIG_KEXEC */
311struct pt_regs;
312struct task_struct;
313static inline void crash_kexec(struct pt_regs *regs) { }
314static inline int kexec_should_crash(struct task_struct *p) { return 0; }
315#endif /* CONFIG_KEXEC */
316#endif /* LINUX_KEXEC_H */