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 */
27 extern char _end[];
28 extern unsigned char _compressed_start[];
29 extern 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
37 static unsigned long free_mem_ptr = (unsigned long) _end;
38 static 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
mem_safe_offset(void)66 unsigned 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
decompress_kernel(void)77 void *decompress_kernel(void)
78 {
79 void *output = (void *)decompress_offset;
80
81 __decompress(_compressed_start, _compressed_end - _compressed_start,
82 NULL, NULL, output, 0, NULL, error);
83 return output;
84 }
85