arch/s390/boot/compressed/misc.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/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
  68 static int puts(const char *s)
  69 {
  70         sclp_early_printk(s);
  71         return 0;
  72 }
  73
  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
  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