Merge branch 'master' of git://git2.kernel.org/pub/scm/linux/kernel/git/torvalds...
[linux-2.6/linux-2.6-openrd.git] / include / linux / crash_dump.h
blob0026f267da20d6e9f1a0dc5343b978c1e5f0b6f1
1 #ifndef LINUX_CRASH_DUMP_H
2 #define LINUX_CRASH_DUMP_H
4 #ifdef CONFIG_CRASH_DUMP
5 #include <linux/kexec.h>
6 #include <linux/device.h>
7 #include <linux/proc_fs.h>
9 #define ELFCORE_ADDR_MAX (-1ULL)
10 #define ELFCORE_ADDR_ERR (-2ULL)
12 extern unsigned long long elfcorehdr_addr;
14 extern ssize_t copy_oldmem_page(unsigned long, char *, size_t,
15 unsigned long, int);
17 /* Architecture code defines this if there are other possible ELF
18 * machine types, e.g. on bi-arch capable hardware. */
19 #ifndef vmcore_elf_check_arch_cross
20 #define vmcore_elf_check_arch_cross(x) 0
21 #endif
23 #define vmcore_elf_check_arch(x) (elf_check_arch(x) || vmcore_elf_check_arch_cross(x))
26 * is_kdump_kernel() checks whether this kernel is booting after a panic of
27 * previous kernel or not. This is determined by checking if previous kernel
28 * has passed the elf core header address on command line.
30 * This is not just a test if CONFIG_CRASH_DUMP is enabled or not. It will
31 * return 1 if CONFIG_CRASH_DUMP=y and if kernel is booting after a panic of
32 * previous kernel.
35 static inline int is_kdump_kernel(void)
37 return (elfcorehdr_addr != ELFCORE_ADDR_MAX) ? 1 : 0;
40 /* is_vmcore_usable() checks if the kernel is booting after a panic and
41 * the vmcore region is usable.
43 * This makes use of the fact that due to alignment -2ULL is not
44 * a valid pointer, much in the vain of IS_ERR(), except
45 * dealing directly with an unsigned long long rather than a pointer.
48 static inline int is_vmcore_usable(void)
50 return is_kdump_kernel() && elfcorehdr_addr != ELFCORE_ADDR_ERR ? 1 : 0;
53 /* vmcore_unusable() marks the vmcore as unusable,
54 * without disturbing the logic of is_kdump_kernel()
57 static inline void vmcore_unusable(void)
59 if (is_kdump_kernel())
60 elfcorehdr_addr = ELFCORE_ADDR_ERR;
62 #else /* !CONFIG_CRASH_DUMP */
63 static inline int is_kdump_kernel(void) { return 0; }
64 #endif /* CONFIG_CRASH_DUMP */
66 extern unsigned long saved_max_pfn;
67 #endif /* LINUX_CRASHDUMP_H */