diff options
Diffstat (limited to 'arch/s390/boot/compressed/misc.c')
| -rw-r--r-- | arch/s390/boot/compressed/misc.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/arch/s390/boot/compressed/misc.c b/arch/s390/boot/compressed/misc.c new file mode 100644 index 00000000..465eca75 --- /dev/null +++ b/arch/s390/boot/compressed/misc.c @@ -0,0 +1,168 @@ +/* + * Definitions and wrapper functions for kernel decompressor + * + * Copyright IBM Corp. 2010 + * + * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> + */ + +#include <asm/uaccess.h> +#include <asm/page.h> +#include <asm/ipl.h> +#include "sizes.h" + +/* + * gzip declarations + */ +#define STATIC static + +#undef memset +#undef memcpy +#undef memmove +#define memmove memmove +#define memzero(s, n) memset((s), 0, (n)) + +/* Symbols defined by linker scripts */ +extern char input_data[]; +extern int input_len; +extern char _text, _end; +extern char _bss, _ebss; + +static void error(char *m); + +static unsigned long free_mem_ptr; +static unsigned long free_mem_end_ptr; + +#ifdef CONFIG_HAVE_KERNEL_BZIP2 +#define HEAP_SIZE 0x400000 +#else +#define HEAP_SIZE 0x10000 +#endif + +#ifdef CONFIG_KERNEL_GZIP +#include "../../../../lib/decompress_inflate.c" +#endif + +#ifdef CONFIG_KERNEL_BZIP2 +#include "../../../../lib/decompress_bunzip2.c" +#endif + +#ifdef CONFIG_KERNEL_LZMA +#include "../../../../lib/decompress_unlzma.c" +#endif + +#ifdef CONFIG_KERNEL_LZO +#include "../../../../lib/decompress_unlzo.c" +#endif + +#ifdef CONFIG_KERNEL_XZ +#include "../../../../lib/decompress_unxz.c" +#endif + +extern _sclp_print_early(const char *); + +static int puts(const char *s) +{ + _sclp_print_early(s); + return 0; +} + +void *memset(void *s, int c, size_t n) +{ + char *xs; + + if (c == 0) + return __builtin_memset(s, 0, n); + + xs = (char *) s; + if (n > 0) + do { + *xs++ = c; + } while (--n > 0); + return s; +} + +void *memcpy(void *__dest, __const void *__src, size_t __n) +{ + return __builtin_memcpy(__dest, __src, __n); +} + +void *memmove(void *__dest, __const void *__src, size_t __n) +{ + char *d; + const char *s; + + if (__dest <= __src) + return __builtin_memcpy(__dest, __src, __n); + d = __dest + __n; + s = __src + __n; + while (__n--) + *--d = *--s; + return __dest; +} + +static void error(char *x) +{ + unsigned long long psw = 0x000a0000deadbeefULL; + + puts("\n\n"); + puts(x); + puts("\n\n -- System halted"); + + asm volatile("lpsw %0" : : "Q" (psw)); +} + +/* + * Safe guard the ipl parameter block against a memory area that will be + * overwritten. The validity check for the ipl parameter block is complex + * (see cio_get_iplinfo and ipl_save_parameters) but if the pointer to + * the ipl parameter block intersects with the passed memory area we can + * safely assume that we can read from that memory. In that case just copy + * the memory to IPL_PARMBLOCK_ORIGIN even if there is no ipl parameter + * block. + */ +static void check_ipl_parmblock(void *start, unsigned long size) +{ + void *src, *dst; + + src = (void *)(unsigned long) S390_lowcore.ipl_parmblock_ptr; + if (src + PAGE_SIZE <= start || src >= start + size) + return; + dst = (void *) IPL_PARMBLOCK_ORIGIN; + memmove(dst, src, PAGE_SIZE); + S390_lowcore.ipl_parmblock_ptr = IPL_PARMBLOCK_ORIGIN; +} + +unsigned long decompress_kernel(void) +{ + unsigned long output_addr; + unsigned char *output; + + output_addr = ((unsigned long) &_end + HEAP_SIZE + 4095UL) & -4096UL; + check_ipl_parmblock((void *) 0, output_addr + SZ__bss_start); + memset(&_bss, 0, &_ebss - &_bss); + free_mem_ptr = (unsigned long)&_end; + free_mem_end_ptr = free_mem_ptr + HEAP_SIZE; + output = (unsigned char *) output_addr; + +#ifdef CONFIG_BLK_DEV_INITRD + /* + * Move the initrd right behind the end of the decompressed + * kernel image. + */ + if (INITRD_START && INITRD_SIZE && + INITRD_START < (unsigned long) output + SZ__bss_start) { + check_ipl_parmblock(output + SZ__bss_start, + INITRD_START + INITRD_SIZE); + memmove(output + SZ__bss_start, + (void *) INITRD_START, INITRD_SIZE); + INITRD_START = (unsigned long) output + SZ__bss_start; + } +#endif + + puts("Uncompressing Linux... "); + decompress(input_data, input_len, NULL, NULL, output, NULL, error); + puts("Ok, booting the kernel.\n"); + return (unsigned long) output; +} + |