diff options
Diffstat (limited to 'include/linux/crash_dump.h')
| -rw-r--r-- | include/linux/crash_dump.h | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/include/linux/crash_dump.h b/include/linux/crash_dump.h index de027d1db745..0acf3b737e2e 100644 --- a/include/linux/crash_dump.h +++ b/include/linux/crash_dump.h @@ -8,6 +8,7 @@ #include <linux/proc_fs.h> #define ELFCORE_ADDR_MAX (-1ULL) +#define ELFCORE_ADDR_ERR (-2ULL) extern unsigned long long elfcorehdr_addr; @@ -38,6 +39,29 @@ static inline int is_kdump_kernel(void) { return (elfcorehdr_addr != ELFCORE_ADDR_MAX) ? 1 : 0; } + +/* is_vmcore_usable() checks if the kernel is booting after a panic and + * the vmcore region is usable. + * + * This makes use of the fact that due to alignment -2ULL is not + * a valid pointer, much in the vain of IS_ERR(), except + * dealing directly with an unsigned long long rather than a pointer. + */ + +static inline int is_vmcore_usable(void) +{ + return is_kdump_kernel() && elfcorehdr_addr != ELFCORE_ADDR_ERR ? 1 : 0; +} + +/* vmcore_unusable() marks the vmcore as unusable, + * without disturbing the logic of is_kdump_kernel() + */ + +static inline void vmcore_unusable(void) +{ + if (is_kdump_kernel()) + elfcorehdr_addr = ELFCORE_ADDR_ERR; +} #else /* !CONFIG_CRASH_DUMP */ static inline int is_kdump_kernel(void) { return 0; } #endif /* CONFIG_CRASH_DUMP */ |