linux-hardened/include/linux/crash_dump.h
Alexey Dobriyan 405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00

67 lines
1.9 KiB
C

#ifndef LINUX_CRASH_DUMP_H
#define LINUX_CRASH_DUMP_H
#ifdef CONFIG_CRASH_DUMP
#include <linux/kexec.h>
#include <linux/device.h>
#include <linux/proc_fs.h>
#define ELFCORE_ADDR_MAX (-1ULL)
#define ELFCORE_ADDR_ERR (-2ULL)
extern unsigned long long elfcorehdr_addr;
extern ssize_t copy_oldmem_page(unsigned long, char *, size_t,
unsigned long, int);
/* Architecture code defines this if there are other possible ELF
* machine types, e.g. on bi-arch capable hardware. */
#ifndef vmcore_elf_check_arch_cross
#define vmcore_elf_check_arch_cross(x) 0
#endif
#define vmcore_elf_check_arch(x) (elf_check_arch(x) || vmcore_elf_check_arch_cross(x))
/*
* is_kdump_kernel() checks whether this kernel is booting after a panic of
* previous kernel or not. This is determined by checking if previous kernel
* has passed the elf core header address on command line.
*
* This is not just a test if CONFIG_CRASH_DUMP is enabled or not. It will
* return 1 if CONFIG_CRASH_DUMP=y and if kernel is booting after a panic of
* previous kernel.
*/
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 */
extern unsigned long saved_max_pfn;
#endif /* LINUX_CRASHDUMP_H */