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/* Symbols defined by linker scripts */
27extern char _end[];
28extern unsigned char _compressed_start[];
29extern unsigned char _compressed_end[];
30
31#ifdef CONFIG_HAVE_KERNEL_BZIP2
32#define BOOT_HEAP_SIZE	0x400000
33#else
34#define BOOT_HEAP_SIZE	0x10000
35#endif
36
37static unsigned long free_mem_ptr = (unsigned long) _end;
38static unsigned long free_mem_end_ptr = (unsigned long) _end + BOOT_HEAP_SIZE;
39
40#ifdef CONFIG_KERNEL_GZIP
41#include "../../../../lib/decompress_inflate.c"
42#endif
43
44#ifdef CONFIG_KERNEL_BZIP2
45#include "../../../../lib/decompress_bunzip2.c"
46#endif
47
48#ifdef CONFIG_KERNEL_LZ4
49#include "../../../../lib/decompress_unlz4.c"
50#endif
51
52#ifdef CONFIG_KERNEL_LZMA
53#include "../../../../lib/decompress_unlzma.c"
54#endif
55
56#ifdef CONFIG_KERNEL_LZO
57#include "../../../../lib/decompress_unlzo.c"
58#endif
59
60#ifdef CONFIG_KERNEL_XZ
61#include "../../../../lib/decompress_unxz.c"
62#endif
63
64#define decompress_offset ALIGN((unsigned long)_end + BOOT_HEAP_SIZE, PAGE_SIZE)
65
66unsigned long mem_safe_offset(void)
67{
68	/*
69	 * due to 4MB HEAD_SIZE for bzip2
70	 * 'decompress_offset + vmlinux.image_size' could be larger than
71	 * kernel at final position + its .bss, so take the larger of two
72	 */
73	return max(decompress_offset + vmlinux.image_size,
74		   vmlinux.default_lma + vmlinux.image_size + vmlinux.bss_size);
75}
76
77void *decompress_kernel(void)
78{
79	void *output = (void *)decompress_offset;
80
81	__decompress(_compressed_start, _compressed_end - _compressed_start,
82		     NULL, NULL, output, vmlinux.image_size, NULL, error);
83	return output;
84}
85