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/kernel.h>
11#include <linux/string.h>
12#include <asm/page.h>
13#include "decompressor.h"
14
15/*
16 * gzip declarations
17 */
18#define STATIC static
19
20#undef memset
21#undef memcpy
22#undef memmove
23#define memmove memmove
24#define memzero(s, n) memset((s), 0, (n))
25
26#if defined(CONFIG_KERNEL_BZIP2)
27#define BOOT_HEAP_SIZE	0x400000
28#elif defined(CONFIG_KERNEL_ZSTD)
29#define BOOT_HEAP_SIZE	0x30000
30#else
31#define BOOT_HEAP_SIZE	0x10000
32#endif
33
34static unsigned long free_mem_ptr = (unsigned long) _end;
35static unsigned long free_mem_end_ptr = (unsigned long) _end + BOOT_HEAP_SIZE;
36
37#ifdef CONFIG_KERNEL_GZIP
38#include "../../../../lib/decompress_inflate.c"
39#endif
40
41#ifdef CONFIG_KERNEL_BZIP2
42#include "../../../../lib/decompress_bunzip2.c"
43#endif
44
45#ifdef CONFIG_KERNEL_LZ4
46#include "../../../../lib/decompress_unlz4.c"
47#endif
48
49#ifdef CONFIG_KERNEL_LZMA
50#include "../../../../lib/decompress_unlzma.c"
51#endif
52
53#ifdef CONFIG_KERNEL_LZO
54#include "../../../../lib/decompress_unlzo.c"
55#endif
56
57#ifdef CONFIG_KERNEL_XZ
58#include "../../../../lib/decompress_unxz.c"
59#endif
60
61#ifdef CONFIG_KERNEL_ZSTD
62#include "../../../../lib/decompress_unzstd.c"
63#endif
64
65#define decompress_offset ALIGN((unsigned long)_end + BOOT_HEAP_SIZE, PAGE_SIZE)
66
67unsigned long mem_safe_offset(void)
68{
69	/*
70	 * due to 4MB HEAD_SIZE for bzip2
71	 * 'decompress_offset + vmlinux.image_size' could be larger than
72	 * kernel at final position + its .bss, so take the larger of two
73	 */
74	return max(decompress_offset + vmlinux.image_size,
75		   vmlinux.default_lma + vmlinux.image_size + vmlinux.bss_size);
76}
77
78void *decompress_kernel(void)
79{
80	void *output = (void *)decompress_offset;
81
82	__decompress(_compressed_start, _compressed_end - _compressed_start,
83		     NULL, NULL, output, vmlinux.image_size, NULL, error);
84	return output;
85}