kernel_optimize_test/arch/s390/boot/compressed/misc.c
Martin Schwidefsky 06c0dd72ae [S390] fix boot failures with compressed kernels
Fix two bugs with the kernel image compression:
1) reset the bss section of the compressed vmlinux
2) clear the high half of the registers for 64 bit early enough
   for the decompression step

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-03-24 11:49:54 +01:00

159 lines
3.5 KiB
C

/*
* 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 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
extern _sclp_print_early(const char *);
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;
check_ipl_parmblock((void *) 0, (unsigned long) output + 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 *) ((free_mem_end_ptr + 4095UL) & -4096UL);
#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;
}