aboutsummaryrefslogtreecommitdiff
path: root/include/linux/kexec.h
blob: 2cc643c6e8708207aea022d0e1f790f805364be2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
#ifndef LINUX_KEXEC_H
#define LINUX_KEXEC_H

#define IND_DESTINATION_BIT 0
#define IND_INDIRECTION_BIT 1
#define IND_DONE_BIT        2
#define IND_SOURCE_BIT      3

#define IND_DESTINATION  (1 << IND_DESTINATION_BIT)
#define IND_INDIRECTION  (1 << IND_INDIRECTION_BIT)
#define IND_DONE         (1 << IND_DONE_BIT)
#define IND_SOURCE       (1 << IND_SOURCE_BIT)
#define IND_FLAGS (IND_DESTINATION | IND_INDIRECTION | IND_DONE | IND_SOURCE)

#if !defined(__ASSEMBLY__)

#include <uapi/linux/kexec.h>

#ifdef CONFIG_KEXEC_CORE
#include <linux/list.h>
#include <linux/linkage.h>
#include <linux/compat.h>
#include <linux/ioport.h>
#include <linux/elfcore.h>
#include <linux/elf.h>
#include <linux/module.h>
#include <asm/kexec.h>

/* Verify architecture specific macros are defined */

#ifndef KEXEC_SOURCE_MEMORY_LIMIT
#error KEXEC_SOURCE_MEMORY_LIMIT not defined
#endif

#ifndef KEXEC_DESTINATION_MEMORY_LIMIT
#error KEXEC_DESTINATION_MEMORY_LIMIT not defined
#endif

#ifndef KEXEC_CONTROL_MEMORY_LIMIT
#error KEXEC_CONTROL_MEMORY_LIMIT not defined
#endif

#ifndef KEXEC_CONTROL_MEMORY_GFP
#define KEXEC_CONTROL_MEMORY_GFP GFP_KERNEL
#endif

#ifndef KEXEC_CONTROL_PAGE_SIZE
#error KEXEC_CONTROL_PAGE_SIZE not defined
#endif

#ifndef KEXEC_ARCH
#error KEXEC_ARCH not defined
#endif

#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
#endif

#ifndef KEXEC_CRASH_MEM_ALIGN
#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
#endif

#define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
#define KEXEC_CORE_NOTE_NAME "CORE"
#define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
#define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
/*
 * The per-cpu notes area is a list of notes terminated by a "NULL"
 * note header.  For kdump, the code in vmcore.c runs in the context
 * of the second kernel to combine them into one note.
 */
#ifndef KEXEC_NOTE_BYTES
#define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) +		\
			    KEXEC_CORE_NOTE_NAME_BYTES +		\
			    KEXEC_CORE_NOTE_DESC_BYTES )
#endif

/*
 * This structure is used to hold the arguments that are used when loading
 * kernel binaries.
 */

typedef unsigned long kimage_entry_t;

struct kexec_segment {
	/*
	 * This pointer can point to user memory if kexec_load() system
	 * call is used or will point to kernel memory if
	 * kexec_file_load() system call is used.
	 *
	 * Use ->buf when expecting to deal with user memory and use ->kbuf
	 * when expecting to deal with kernel memory.
	 */
	union {
		void __user *buf;
		void *kbuf;
	};
	size_t bufsz;
	unsigned long mem;
	size_t memsz;
};

#ifdef CONFIG_COMPAT
struct compat_kexec_segment {
	compat_uptr_t buf;
	compat_size_t bufsz;
	compat_ulong_t mem;	/* User space sees this as a (void *) ... */
	compat_size_t memsz;
};
#endif

#ifdef CONFIG_KEXEC_FILE
struct purgatory_info {
	/* Pointer to elf header of read only purgatory */
	Elf_Ehdr *ehdr;

	/* Pointer to purgatory sechdrs which are modifiable */
	Elf_Shdr *sechdrs;
	/*
	 * Temporary buffer location where purgatory is loaded and relocated
	 * This memory can be freed post image load
	 */
	void *purgatory_buf;

	/* Address where purgatory is finally loaded and is executed from */
	unsigned long purgatory_load_addr;
};

typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
			     unsigned long kernel_len, char *initrd,
			     unsigned long initrd_len, char *cmdline,
			     unsigned long cmdline_len);
typedef int (kexec_cleanup_t)(void *loader_data);

#ifdef CONFIG_KEXEC_VERIFY_SIG
typedef int (kexec_verify_sig_t)(const char *kernel_buf,
				 unsigned long kernel_len);
#endif

struct kexec_file_ops {
	kexec_probe_t *probe;
	kexec_load_t *load;
	kexec_cleanup_t *cleanup;
#ifdef CONFIG_KEXEC_VERIFY_SIG
	kexec_verify_sig_t *verify_sig;
#endif
};
#endif

struct kimage {
	kimage_entry_t head;
	kimage_entry_t *entry;
	kimage_entry_t *last_entry;

	unsigned long start;
	struct page *control_code_page;
	struct page *swap_page;

	unsigned long nr_segments;
	struct kexec_segment segment[KEXEC_SEGMENT_MAX];

	struct list_head control_pages;
	struct list_head dest_pages;
	struct list_head unusable_pages;

	/* Address of next control page to allocate for crash kernels. */
	unsigned long control_page;

	/* Flags to indicate special processing */
	unsigned int type : 1;
#define KEXEC_TYPE_DEFAULT 0
#define KEXEC_TYPE_CRASH   1
	unsigned int preserve_context : 1;
	/* If set, we are using file mode kexec syscall */
	unsigned int file_mode:1;

#ifdef ARCH_HAS_KIMAGE_ARCH
	struct kimage_arch arch;
#endif

#ifdef CONFIG_KEXEC_FILE
	/* Additional fields for file based kexec syscall */
	void *kernel_buf;
	unsigned long kernel_buf_len;

	void *initrd_buf;
	unsigned long initrd_buf_len;

	char *cmdline_buf;
	unsigned long cmdline_buf_len;

	/* File operations provided by image loader */
	struct kexec_file_ops *fops;

	/* Image loader handling the kernel can store a pointer here */
	void *image_loader_data;

	/* Information for loading purgatory */
	struct purgatory_info purgatory_info;
#endif
};

/* kexec interface functions */
extern void machine_kexec(struct kimage *image);
extern int machine_kexec_prepare(struct kimage *image);
extern void machine_kexec_cleanup(struct kimage *image);
extern asmlinkage long sys_kexec_load(unsigned long entry,
					unsigned long nr_segments,
					struct kexec_segment __user *segments,
					unsigned long flags);
extern int kernel_kexec(void);
extern int kexec_add_buffer(struct kimage *image, char *buffer,
			    unsigned long bufsz, unsigned long memsz,
			    unsigned long buf_align, unsigned long buf_min,
			    unsigned long buf_max, bool top_down,
			    unsigned long *load_addr);
extern struct page *kimage_alloc_control_pages(struct kimage *image,
						unsigned int order);
extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
				unsigned long max, int top_down,
				unsigned long *load_addr);
extern int kexec_purgatory_get_set_symbol(struct kimage *image,
					  const char *name, void *buf,
					  unsigned int size, bool get_value);
extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
					     const char *name);
extern void __crash_kexec(struct pt_regs *);
extern void crash_kexec(struct pt_regs *);
int kexec_should_crash(struct task_struct *);
void crash_save_cpu(struct pt_regs *regs, int cpu);
void crash_save_vmcoreinfo(void);
void crash_map_reserved_pages(void);
void crash_unmap_reserved_pages(void);
void arch_crash_save_vmcoreinfo(void);
__printf(1, 2)
void vmcoreinfo_append_str(const char *fmt, ...);
unsigned long paddr_vmcoreinfo_note(void);

#define VMCOREINFO_OSRELEASE(value) \
	vmcoreinfo_append_str("OSRELEASE=%s\n", value)
#define VMCOREINFO_PAGESIZE(value) \
	vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
#define VMCOREINFO_SYMBOL(name) \
	vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
#define VMCOREINFO_SIZE(name) \
	vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
			      (unsigned long)sizeof(name))
#define VMCOREINFO_STRUCT_SIZE(name) \
	vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
			      (unsigned long)sizeof(struct name))
#define VMCOREINFO_OFFSET(name, field) \
	vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
			      (unsigned long)offsetof(struct name, field))
#define VMCOREINFO_LENGTH(name, value) \
	vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
#define VMCOREINFO_NUMBER(name) \
	vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
#define VMCOREINFO_CONFIG(name) \
	vmcoreinfo_append_str("CONFIG_%s=y\n", #name)

extern struct kimage *kexec_image;
extern struct kimage *kexec_crash_image;
extern int kexec_load_disabled;

#ifndef kexec_flush_icache_page
#define kexec_flush_icache_page(page)
#endif

/* List of defined/legal kexec flags */
#ifndef CONFIG_KEXEC_JUMP
#define KEXEC_FLAGS    KEXEC_ON_CRASH
#else
#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
#endif

/* List of defined/legal kexec file flags */
#define KEXEC_FILE_FLAGS	(KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
				 KEXEC_FILE_NO_INITRAMFS)

#define VMCOREINFO_BYTES           (4096)
#define VMCOREINFO_NOTE_NAME       "VMCOREINFO"
#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
#define VMCOREINFO_NOTE_SIZE       (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
				    + VMCOREINFO_NOTE_NAME_BYTES)

/* Location of a reserved region to hold the crash kernel.
 */
extern struct resource crashk_res;
extern struct resource crashk_low_res;
typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
extern note_buf_t __percpu *crash_notes;
extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
extern size_t vmcoreinfo_size;
extern size_t vmcoreinfo_max_size;

/* flag to track if kexec reboot is in progress */
extern bool kexec_in_progress;

int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
		unsigned long long *crash_size, unsigned long long *crash_base);
int parse_crashkernel_high(char *cmdline, unsigned long long system_ram,
		unsigned long long *crash_size, unsigned long long *crash_base);
int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
		unsigned long long *crash_size, unsigned long long *crash_base);
int crash_shrink_memory(unsigned long new_size);
size_t crash_get_memory_size(void);
void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);

int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
					 unsigned long buf_len);
void * __weak arch_kexec_kernel_image_load(struct kimage *image);
int __weak arch_kimage_file_post_load_cleanup(struct kimage *image);
int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
					unsigned long buf_len);
int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
					Elf_Shdr *sechdrs, unsigned int relsec);
int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
					unsigned int relsec);

#else /* !CONFIG_KEXEC_CORE */
struct pt_regs;
struct task_struct;
static inline void __crash_kexec(struct pt_regs *regs) { }
static inline void crash_kexec(struct pt_regs *regs) { }
static inline int kexec_should_crash(struct task_struct *p) { return 0; }
#define kexec_in_progress false
#endif /* CONFIG_KEXEC_CORE */

#endif /* !defined(__ASSEBMLY__) */

#endif /* LINUX_KEXEC_H */