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git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - include/linux/crash_dump.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef LINUX_CRASH_DUMP_H
3 #define LINUX_CRASH_DUMP_H
5 #include <linux/kexec.h>
6 #include <linux/proc_fs.h>
8 #include <uapi/linux/vmcore.h>
10 #include <asm/pgtable.h> /* for pgprot_t */
12 #ifdef CONFIG_CRASH_DUMP
13 #define ELFCORE_ADDR_MAX (-1ULL)
14 #define ELFCORE_ADDR_ERR (-2ULL)
16 extern unsigned long long elfcorehdr_addr
;
17 extern unsigned long long elfcorehdr_size
;
19 extern int elfcorehdr_alloc(unsigned long long *addr
, unsigned long long *size
);
20 extern void elfcorehdr_free(unsigned long long addr
);
21 extern ssize_t
elfcorehdr_read(char *buf
, size_t count
, u64
*ppos
);
22 extern ssize_t
elfcorehdr_read_notes(char *buf
, size_t count
, u64
*ppos
);
23 extern int remap_oldmem_pfn_range(struct vm_area_struct
*vma
,
24 unsigned long from
, unsigned long pfn
,
25 unsigned long size
, pgprot_t prot
);
27 extern ssize_t
copy_oldmem_page(unsigned long, char *, size_t,
29 extern ssize_t
copy_oldmem_page_encrypted(unsigned long pfn
, char *buf
,
30 size_t csize
, unsigned long offset
,
33 void vmcore_cleanup(void);
35 /* Architecture code defines this if there are other possible ELF
36 * machine types, e.g. on bi-arch capable hardware. */
37 #ifndef vmcore_elf_check_arch_cross
38 #define vmcore_elf_check_arch_cross(x) 0
42 * Architecture code can redefine this if there are any special checks
43 * needed for 32-bit ELF or 64-bit ELF vmcores. In case of 32-bit
44 * only architecture, vmcore_elf64_check_arch can be set to zero.
46 #ifndef vmcore_elf32_check_arch
47 #define vmcore_elf32_check_arch(x) elf_check_arch(x)
50 #ifndef vmcore_elf64_check_arch
51 #define vmcore_elf64_check_arch(x) (elf_check_arch(x) || vmcore_elf_check_arch_cross(x))
55 * is_kdump_kernel() checks whether this kernel is booting after a panic of
56 * previous kernel or not. This is determined by checking if previous kernel
57 * has passed the elf core header address on command line.
59 * This is not just a test if CONFIG_CRASH_DUMP is enabled or not. It will
60 * return true if CONFIG_CRASH_DUMP=y and if kernel is booting after a panic
64 static inline bool is_kdump_kernel(void)
66 return elfcorehdr_addr
!= ELFCORE_ADDR_MAX
;
69 /* is_vmcore_usable() checks if the kernel is booting after a panic and
70 * the vmcore region is usable.
72 * This makes use of the fact that due to alignment -2ULL is not
73 * a valid pointer, much in the vain of IS_ERR(), except
74 * dealing directly with an unsigned long long rather than a pointer.
77 static inline int is_vmcore_usable(void)
79 return is_kdump_kernel() && elfcorehdr_addr
!= ELFCORE_ADDR_ERR
? 1 : 0;
82 /* vmcore_unusable() marks the vmcore as unusable,
83 * without disturbing the logic of is_kdump_kernel()
86 static inline void vmcore_unusable(void)
88 if (is_kdump_kernel())
89 elfcorehdr_addr
= ELFCORE_ADDR_ERR
;
92 #define HAVE_OLDMEM_PFN_IS_RAM 1
93 extern int register_oldmem_pfn_is_ram(int (*fn
)(unsigned long pfn
));
94 extern void unregister_oldmem_pfn_is_ram(void);
96 #else /* !CONFIG_CRASH_DUMP */
97 static inline bool is_kdump_kernel(void) { return 0; }
98 #endif /* CONFIG_CRASH_DUMP */
100 extern unsigned long saved_max_pfn
;
102 /* Device Dump information to be filled by drivers */
103 struct vmcoredd_data
{
104 char dump_name
[VMCOREDD_MAX_NAME_BYTES
]; /* Unique name of the dump */
105 unsigned int size
; /* Size of the dump */
106 /* Driver's registered callback to be invoked to collect dump */
107 int (*vmcoredd_callback
)(struct vmcoredd_data
*data
, void *buf
);
110 #ifdef CONFIG_PROC_VMCORE_DEVICE_DUMP
111 int vmcore_add_device_dump(struct vmcoredd_data
*data
);
113 static inline int vmcore_add_device_dump(struct vmcoredd_data
*data
)
117 #endif /* CONFIG_PROC_VMCORE_DEVICE_DUMP */
118 #endif /* LINUX_CRASHDUMP_H */