1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef LINUX_CRASH_CORE_H
3#define LINUX_CRASH_CORE_H
4
5#include <linux/linkage.h>
6#include <linux/elfcore.h>
7#include <linux/elf.h>
8#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
9#include <asm/crash_core.h>
10#endif
11
12/* Location of a reserved region to hold the crash kernel.
13 */
14extern struct resource crashk_res;
15extern struct resource crashk_low_res;
16
17#define CRASH_CORE_NOTE_NAME "CORE"
18#define CRASH_CORE_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
19#define CRASH_CORE_NOTE_NAME_BYTES ALIGN(sizeof(CRASH_CORE_NOTE_NAME), 4)
20#define CRASH_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
21
22/*
23 * The per-cpu notes area is a list of notes terminated by a "NULL"
24 * note header. For kdump, the code in vmcore.c runs in the context
25 * of the second kernel to combine them into one note.
26 */
27#define CRASH_CORE_NOTE_BYTES ((CRASH_CORE_NOTE_HEAD_BYTES * 2) + \
28 CRASH_CORE_NOTE_NAME_BYTES + \
29 CRASH_CORE_NOTE_DESC_BYTES)
30
31#define VMCOREINFO_BYTES PAGE_SIZE
32#define VMCOREINFO_NOTE_NAME "VMCOREINFO"
33#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
34#define VMCOREINFO_NOTE_SIZE ((CRASH_CORE_NOTE_HEAD_BYTES * 2) + \
35 VMCOREINFO_NOTE_NAME_BYTES + \
36 VMCOREINFO_BYTES)
37
38typedef u32 note_buf_t[CRASH_CORE_NOTE_BYTES/4];
39/* Per cpu memory for storing cpu states in case of system crash. */
40extern note_buf_t __percpu *crash_notes;
41
42void crash_update_vmcoreinfo_safecopy(void *ptr);
43void crash_save_vmcoreinfo(void);
44void arch_crash_save_vmcoreinfo(void);
45__printf(1, 2)
46void vmcoreinfo_append_str(const char *fmt, ...);
47phys_addr_t paddr_vmcoreinfo_note(void);
48
49#define VMCOREINFO_OSRELEASE(value) \
50 vmcoreinfo_append_str("OSRELEASE=%s\n", value)
51#define VMCOREINFO_BUILD_ID() \
52 ({ \
53 static_assert(sizeof(vmlinux_build_id) == 20); \
54 vmcoreinfo_append_str("BUILD-ID=%20phN\n", vmlinux_build_id); \
55 })
56
57#define VMCOREINFO_PAGESIZE(value) \
58 vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
59#define VMCOREINFO_SYMBOL(name) \
60 vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
61#define VMCOREINFO_SYMBOL_ARRAY(name) \
62 vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)name)
63#define VMCOREINFO_SIZE(name) \
64 vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
65 (unsigned long)sizeof(name))
66#define VMCOREINFO_STRUCT_SIZE(name) \
67 vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
68 (unsigned long)sizeof(struct name))
69#define VMCOREINFO_OFFSET(name, field) \
70 vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
71 (unsigned long)offsetof(struct name, field))
72#define VMCOREINFO_TYPE_OFFSET(name, field) \
73 vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
74 (unsigned long)offsetof(name, field))
75#define VMCOREINFO_LENGTH(name, value) \
76 vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
77#define VMCOREINFO_NUMBER(name) \
78 vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
79#define VMCOREINFO_CONFIG(name) \
80 vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
81
82extern unsigned char *vmcoreinfo_data;
83extern size_t vmcoreinfo_size;
84extern u32 *vmcoreinfo_note;
85
86Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type,
87 void *data, size_t data_len);
88void final_note(Elf_Word *buf);
89
90#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
91#ifndef DEFAULT_CRASH_KERNEL_LOW_SIZE
92#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
93#endif
94#endif
95
96int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
97 unsigned long long *crash_size, unsigned long long *crash_base,
98 unsigned long long *low_size, bool *high);
99
100#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
101#ifndef DEFAULT_CRASH_KERNEL_LOW_SIZE
102#define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
103#endif
104#ifndef CRASH_ALIGN
105#define CRASH_ALIGN SZ_2M
106#endif
107#ifndef CRASH_ADDR_LOW_MAX
108#define CRASH_ADDR_LOW_MAX SZ_4G
109#endif
110#ifndef CRASH_ADDR_HIGH_MAX
111#define CRASH_ADDR_HIGH_MAX memblock_end_of_DRAM()
112#endif
113
114void __init reserve_crashkernel_generic(char *cmdline,
115 unsigned long long crash_size,
116 unsigned long long crash_base,
117 unsigned long long crash_low_size,
118 bool high);
119#else
120static inline void __init reserve_crashkernel_generic(char *cmdline,
121 unsigned long long crash_size,
122 unsigned long long crash_base,
123 unsigned long long crash_low_size,
124 bool high)
125{}
126#endif
127
128/* Alignment required for elf header segment */
129#define ELF_CORE_HEADER_ALIGN 4096
130
131struct crash_mem {
132 unsigned int max_nr_ranges;
133 unsigned int nr_ranges;
134 struct range ranges[] __counted_by(max_nr_ranges);
135};
136
137extern int crash_exclude_mem_range(struct crash_mem *mem,
138 unsigned long long mstart,
139 unsigned long long mend);
140extern int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map,
141 void **addr, unsigned long *sz);
142
143struct kimage;
144struct kexec_segment;
145
146#define KEXEC_CRASH_HP_NONE 0
147#define KEXEC_CRASH_HP_ADD_CPU 1
148#define KEXEC_CRASH_HP_REMOVE_CPU 2
149#define KEXEC_CRASH_HP_ADD_MEMORY 3
150#define KEXEC_CRASH_HP_REMOVE_MEMORY 4
151#define KEXEC_CRASH_HP_INVALID_CPU -1U
152
153#endif /* LINUX_CRASH_CORE_H */
154

source code of linux/include/linux/crash_core.h