1 #ifndef LINUX_CRASH_DUMP_H 2 #define LINUX_CRASH_DUMP_H 3 4 #ifdef CONFIG_CRASH_DUMP 5 #include <linux/kexec.h> 6 #include <linux/proc_fs.h> 7 #include <linux/elf.h> 8 9 #include <asm/pgtable.h> /* for pgprot_t */ 10 11 #define ELFCORE_ADDR_MAX (-1ULL) 12 #define ELFCORE_ADDR_ERR (-2ULL) 13 14 extern unsigned long long elfcorehdr_addr; 15 extern unsigned long long elfcorehdr_size; 16 17 extern int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size); 18 extern void elfcorehdr_free(unsigned long long addr); 19 extern ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos); 20 extern ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos); 21 extern int remap_oldmem_pfn_range(struct vm_area_struct *vma, 22 unsigned long from, unsigned long pfn, 23 unsigned long size, pgprot_t prot); 24 25 extern ssize_t copy_oldmem_page(unsigned long, char *, size_t, 26 unsigned long, int); 27 void vmcore_cleanup(void); 28 29 /* Architecture code defines this if there are other possible ELF 30 * machine types, e.g. on bi-arch capable hardware. */ 31 #ifndef vmcore_elf_check_arch_cross 32 #define vmcore_elf_check_arch_cross(x) 0 33 #endif 34 35 /* 36 * Architecture code can redefine this if there are any special checks 37 * needed for 64-bit ELF vmcores. In case of 32-bit only architecture, 38 * this can be set to zero. 39 */ 40 #ifndef vmcore_elf64_check_arch 41 #define vmcore_elf64_check_arch(x) (elf_check_arch(x) || vmcore_elf_check_arch_cross(x)) 42 #endif 43 44 /* 45 * is_kdump_kernel() checks whether this kernel is booting after a panic of 46 * previous kernel or not. This is determined by checking if previous kernel 47 * has passed the elf core header address on command line. 48 * 49 * This is not just a test if CONFIG_CRASH_DUMP is enabled or not. It will 50 * return 1 if CONFIG_CRASH_DUMP=y and if kernel is booting after a panic of 51 * previous kernel. 52 */ 53 54 static inline int is_kdump_kernel(void) 55 { 56 return (elfcorehdr_addr != ELFCORE_ADDR_MAX) ? 1 : 0; 57 } 58 59 /* is_vmcore_usable() checks if the kernel is booting after a panic and 60 * the vmcore region is usable. 61 * 62 * This makes use of the fact that due to alignment -2ULL is not 63 * a valid pointer, much in the vain of IS_ERR(), except 64 * dealing directly with an unsigned long long rather than a pointer. 65 */ 66 67 static inline int is_vmcore_usable(void) 68 { 69 return is_kdump_kernel() && elfcorehdr_addr != ELFCORE_ADDR_ERR ? 1 : 0; 70 } 71 72 /* vmcore_unusable() marks the vmcore as unusable, 73 * without disturbing the logic of is_kdump_kernel() 74 */ 75 76 static inline void vmcore_unusable(void) 77 { 78 if (is_kdump_kernel()) 79 elfcorehdr_addr = ELFCORE_ADDR_ERR; 80 } 81 82 #define HAVE_OLDMEM_PFN_IS_RAM 1 83 extern int register_oldmem_pfn_is_ram(int (*fn)(unsigned long pfn)); 84 extern void unregister_oldmem_pfn_is_ram(void); 85 86 #else /* !CONFIG_CRASH_DUMP */ 87 static inline int is_kdump_kernel(void) { return 0; } 88 #endif /* CONFIG_CRASH_DUMP */ 89 90 extern unsigned long saved_max_pfn; 91 #endif /* LINUX_CRASHDUMP_H */ 92