Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Definitions and wrapper functions for kernel decompressor
4 *
5 * Copyright IBM Corp. 2010
6 *
7 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
8 */
9
10#include <linux/uaccess.h>
11#include <asm/page.h>
12#include <asm/sclp.h>
13#include <asm/ipl.h>
14#include "sizes.h"
15
16/*
17 * gzip declarations
18 */
19#define STATIC static
20
21#undef memset
22#undef memcpy
23#undef memmove
24#define memmove memmove
25#define memzero(s, n) memset((s), 0, (n))
26
27/* Symbols defined by linker scripts */
28extern char input_data[];
29extern int input_len;
30extern char _end[];
31extern char _bss[], _ebss[];
32
33static void error(char *m);
34
35static unsigned long free_mem_ptr;
36static unsigned long free_mem_end_ptr;
37
38#ifdef CONFIG_HAVE_KERNEL_BZIP2
39#define HEAP_SIZE 0x400000
40#else
41#define HEAP_SIZE 0x10000
42#endif
43
44#ifdef CONFIG_KERNEL_GZIP
45#include "../../../../lib/decompress_inflate.c"
46#endif
47
48#ifdef CONFIG_KERNEL_BZIP2
49#include "../../../../lib/decompress_bunzip2.c"
50#endif
51
52#ifdef CONFIG_KERNEL_LZ4
53#include "../../../../lib/decompress_unlz4.c"
54#endif
55
56#ifdef CONFIG_KERNEL_LZMA
57#include "../../../../lib/decompress_unlzma.c"
58#endif
59
60#ifdef CONFIG_KERNEL_LZO
61#include "../../../../lib/decompress_unlzo.c"
62#endif
63
64#ifdef CONFIG_KERNEL_XZ
65#include "../../../../lib/decompress_unxz.c"
66#endif
67
68static int puts(const char *s)
69{
70 sclp_early_printk(s);
71 return 0;
72}
73
74static void error(char *x)
75{
76 unsigned long long psw = 0x000a0000deadbeefULL;
77
78 puts("\n\n");
79 puts(x);
80 puts("\n\n -- System halted");
81
82 asm volatile("lpsw %0" : : "Q" (psw));
83}
84
85unsigned long decompress_kernel(void)
86{
87 void *output, *kernel_end;
88
89 output = (void *) ALIGN((unsigned long) _end + HEAP_SIZE, PAGE_SIZE);
90 kernel_end = output + SZ__bss_start;
91
92#ifdef CONFIG_BLK_DEV_INITRD
93 /*
94 * Move the initrd right behind the end of the decompressed
95 * kernel image. This also prevents initrd corruption caused by
96 * bss clearing since kernel_end will always be located behind the
97 * current bss section..
98 */
99 if (INITRD_START && INITRD_SIZE && kernel_end > (void *) INITRD_START) {
100 memmove(kernel_end, (void *) INITRD_START, INITRD_SIZE);
101 INITRD_START = (unsigned long) kernel_end;
102 }
103#endif
104
105 /*
106 * Clear bss section. free_mem_ptr and free_mem_end_ptr need to be
107 * initialized afterwards since they reside in bss.
108 */
109 memset(_bss, 0, _ebss - _bss);
110 free_mem_ptr = (unsigned long) _end;
111 free_mem_end_ptr = free_mem_ptr + HEAP_SIZE;
112
113 __decompress(input_data, input_len, NULL, NULL, output, 0, NULL, error);
114 return (unsigned long) output;
115}
116