diff options
| -rw-r--r-- | arch/s390/kernel/crash_dump.c | 81 |
1 files changed, 54 insertions, 27 deletions
diff --git a/arch/s390/kernel/crash_dump.c b/arch/s390/kernel/crash_dump.c index d8f35565717..0c9a897a1fb 100644 --- a/arch/s390/kernel/crash_dump.c +++ b/arch/s390/kernel/crash_dump.c @@ -64,6 +64,11 @@ static ssize_t copy_page_real(void *buf, void *src, size_t csize) } /* + * Pointer to ELF header in new kernel + */ +static void *elfcorehdr_newmem; + +/* * Copy one page from "oldmem" * * For the kdump reserved memory this functions performs a swap operation: @@ -368,14 +373,6 @@ static int get_mem_chunk_cnt(void) } /* - * Relocate pointer in order to allow vmcore code access the data - */ -static inline unsigned long relocate(unsigned long addr) -{ - return OLDMEM_BASE + addr; -} - -/* * Initialize ELF loads (new kernel) */ static int loads_init(Elf64_Phdr *phdr, u64 loads_offset) @@ -426,7 +423,7 @@ static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset) ptr = nt_vmcoreinfo(ptr); memset(phdr, 0, sizeof(*phdr)); phdr->p_type = PT_NOTE; - phdr->p_offset = relocate(notes_offset); + phdr->p_offset = notes_offset; phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start); phdr->p_memsz = phdr->p_filesz; return ptr; @@ -435,7 +432,7 @@ static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset) /* * Create ELF core header (new kernel) */ -static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz) +int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) { Elf64_Phdr *phdr_notes, *phdr_loads; int mem_chunk_cnt; @@ -443,6 +440,11 @@ static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz) u32 alloc_size; u64 hdr_off; + if (!OLDMEM_BASE) + return 0; + /* If elfcorehdr= has been passed via cmdline, we use that one */ + if (elfcorehdr_addr != ELFCORE_ADDR_MAX) + return 0; mem_chunk_cnt = get_mem_chunk_cnt(); alloc_size = 0x1000 + get_cpu_cnt() * 0x300 + @@ -460,27 +462,52 @@ static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz) ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off); /* Init loads */ hdr_off = PTR_DIFF(ptr, hdr); - loads_init(phdr_loads, ((unsigned long) hdr) + hdr_off); - *elfcorebuf_sz = hdr_off; - *elfcorebuf = (void *) relocate((unsigned long) hdr); - BUG_ON(*elfcorebuf_sz > alloc_size); + loads_init(phdr_loads, hdr_off); + *addr = (unsigned long long) hdr; + elfcorehdr_newmem = hdr; + *size = (unsigned long long) hdr_off; + BUG_ON(elfcorehdr_size > alloc_size); + return 0; } /* - * Create kdump ELF core header in new kernel, if it has not been passed via - * the "elfcorehdr" kernel parameter + * Free ELF core header (new kernel) */ -static int setup_kdump_elfcorehdr(void) +void elfcorehdr_free(unsigned long long addr) { - size_t elfcorebuf_sz; - char *elfcorebuf; - - if (!OLDMEM_BASE || is_kdump_kernel()) - return -EINVAL; - s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz); - elfcorehdr_addr = (unsigned long long) elfcorebuf; - elfcorehdr_size = elfcorebuf_sz; - return 0; + if (!elfcorehdr_newmem) + return; + kfree((void *)(unsigned long)addr); +} + +/* + * Read from ELF header + */ +ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos) +{ + void *src = (void *)(unsigned long)*ppos; + + src = elfcorehdr_newmem ? src : src - OLDMEM_BASE; + memcpy(buf, src, count); + *ppos += count; + return count; } -subsys_initcall(setup_kdump_elfcorehdr); +/* + * Read from ELF notes data + */ +ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) +{ + void *src = (void *)(unsigned long)*ppos; + int rc; + + if (elfcorehdr_newmem) { + memcpy(buf, src, count); + } else { + rc = copy_from_oldmem(buf, src, count); + if (rc) + return rc; + } + *ppos += count; + return count; +} |