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 */
28 extern char input_data[];
29 extern int input_len;
30 extern char _end[];
31 extern char _bss[], _ebss[];
32
33 static void error(char *m);
34
35 static unsigned long free_mem_ptr;
36 static 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
puts(const char * s)68 static int puts(const char *s)
69 {
70 sclp_early_printk(s);
71 return 0;
72 }
73
error(char * x)74 static 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
decompress_kernel(void)85 unsigned 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
117