#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);
-extern const struct file_operations proc_vmcore_operations;
-extern struct proc_dir_entry *proc_vmcore;
/* Architecture code defines this if there are other possible ELF
* machine types, e.g. on bi-arch capable hardware. */
{
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 */