arch/s390/boot/compressed/decompressor.c

   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_KERNEL_BZIP2
  32 #define BOOT_HEAP_SIZE  0x400000
  33 #elif CONFIG_KERNEL_ZSTD
  34 #define BOOT_HEAP_SIZE  0x30000
  35 #else
  36 #define BOOT_HEAP_SIZE  0x10000
  37 #endif
  38
  39 static unsigned long free_mem_ptr = (unsigned long) _end;
  40 static unsigned long free_mem_end_ptr = (unsigned long) _end + BOOT_HEAP_SIZE;
  41
  42 #ifdef CONFIG_KERNEL_GZIP
  43 #include "../../../../lib/decompress_inflate.c"
  44 #endif
  45
  46 #ifdef CONFIG_KERNEL_BZIP2
  47 #include "../../../../lib/decompress_bunzip2.c"
  48 #endif
  49
  50 #ifdef CONFIG_KERNEL_LZ4
  51 #include "../../../../lib/decompress_unlz4.c"
  52 #endif
  53
  54 #ifdef CONFIG_KERNEL_LZMA
  55 #include "../../../../lib/decompress_unlzma.c"
  56 #endif
  57
  58 #ifdef CONFIG_KERNEL_LZO
  59 #include "../../../../lib/decompress_unlzo.c"
  60 #endif
  61
  62 #ifdef CONFIG_KERNEL_XZ
  63 #include "../../../../lib/decompress_unxz.c"
  64 #endif
  65
  66 #ifdef CONFIG_KERNEL_ZSTD
  67 #include "../../../../lib/decompress_unzstd.c"
  68 #endif
  69
  70 #define decompress_offset ALIGN((unsigned long)_end + BOOT_HEAP_SIZE, PAGE_SIZE)
  71
  72 unsigned long mem_safe_offset(void)
  73 {
  74         /*
  75          * due to 4MB HEAD_SIZE for bzip2
  76          * 'decompress_offset + vmlinux.image_size' could be larger than
  77          * kernel at final position + its .bss, so take the larger of two
  78          */
  79         return max(decompress_offset + vmlinux.image_size,
  80                    vmlinux.default_lma + vmlinux.image_size + vmlinux.bss_size);
  81 }
  82
  83 void *decompress_kernel(void)
  84 {
  85         void *output = (void *)decompress_offset;
  86
  87         __decompress(_compressed_start, _compressed_end - _compressed_start,
  88                      NULL, NULL, output, 0, NULL, error);
  89         return output;
  90 }