1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * misc.c 4 * 5 * This is a collection of several routines from gzip-1.0.3 6 * adapted for Linux. 7 * 8 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994 9 * 10 * Modified for ARM Linux by Russell King 11 * 12 * Nicolas Pitre <nico@visuaide.com> 1999/04/14 : 13 * For this code to run directly from Flash, all constant variables must 14 * be marked with 'const' and all other variables initialized at run-time 15 * only. This way all non constant variables will end up in the bss segment, 16 * which should point to addresses in RAM and cleared to 0 on start. 17 * This allows for a much quicker boot time. 18 * 19 * Modified for Alpha, from the ARM version, by Jay Estabrook 2003. 20 */ 21 22 #include <linux/kernel.h> 23 #include <linux/slab.h> 24 25 #include <linux/uaccess.h> 26 27 #define memzero(s,n) memset ((s),0,(n)) 28 #define puts srm_printk 29 extern long srm_printk(const char *, ...) 30 __attribute__ ((format (printf, 1, 2))); 31 32 /* 33 * gzip declarations 34 */ 35 #define OF(args) args 36 #define STATIC static 37 38 typedef unsigned char uch; 39 typedef unsigned short ush; 40 typedef unsigned long ulg; 41 42 #define WSIZE 0x8000 /* Window size must be at least 32k, */ 43 /* and a power of two */ 44 45 static uch *inbuf; /* input buffer */ 46 static uch *window; /* Sliding window buffer */ 47 48 static unsigned insize; /* valid bytes in inbuf */ 49 static unsigned inptr; /* index of next byte to be processed in inbuf */ 50 static unsigned outcnt; /* bytes in output buffer */ 51 52 /* gzip flag byte */ 53 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ 54 #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */ 55 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ 56 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ 57 #define COMMENT 0x10 /* bit 4 set: file comment present */ 58 #define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */ 59 #define RESERVED 0xC0 /* bit 6,7: reserved */ 60 61 #define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf()) 62 63 /* Diagnostic functions */ 64 #ifdef DEBUG 65 # define Assert(cond,msg) {if(!(cond)) error(msg);} 66 # define Trace(x) fprintf x 67 # define Tracev(x) {if (verbose) fprintf x ;} 68 # define Tracevv(x) {if (verbose>1) fprintf x ;} 69 # define Tracec(c,x) {if (verbose && (c)) fprintf x ;} 70 # define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;} 71 #else 72 # define Assert(cond,msg) 73 # define Trace(x) 74 # define Tracev(x) 75 # define Tracevv(x) 76 # define Tracec(c,x) 77 # define Tracecv(c,x) 78 #endif 79 80 static int fill_inbuf(void); 81 static void flush_window(void); 82 static void error(char *m); 83 84 static char *input_data; 85 static int input_data_size; 86 87 static uch *output_data; 88 static ulg output_ptr; 89 static ulg bytes_out; 90 91 static void error(char *m); 92 static void gzip_mark(void **); 93 static void gzip_release(void **); 94 95 extern int end; 96 static ulg free_mem_ptr; 97 static ulg free_mem_end_ptr; 98 99 #define HEAP_SIZE 0x3000 100 101 #include "../../../lib/inflate.c" 102 103 /* =========================================================================== 104 * Fill the input buffer. This is called only when the buffer is empty 105 * and at least one byte is really needed. 106 */ 107 int fill_inbuf(void) 108 { 109 if (insize != 0) 110 error("ran out of input data"); 111 112 inbuf = input_data; 113 insize = input_data_size; 114 115 inptr = 1; 116 return inbuf[0]; 117 } 118 119 /* =========================================================================== 120 * Write the output window window[0..outcnt-1] and update crc and bytes_out. 121 * (Used for the decompressed data only.) 122 */ 123 void flush_window(void) 124 { 125 ulg c = crc; 126 unsigned n; 127 uch *in, *out, ch; 128 129 in = window; 130 out = &output_data[output_ptr]; 131 for (n = 0; n < outcnt; n++) { 132 ch = *out++ = *in++; 133 c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8); 134 } 135 crc = c; 136 bytes_out += (ulg)outcnt; 137 output_ptr += (ulg)outcnt; 138 outcnt = 0; 139 /* puts("."); */ 140 } 141 142 static void error(char *x) 143 { 144 puts("\n\n"); 145 puts(x); 146 puts("\n\n -- System halted"); 147 148 while(1); /* Halt */ 149 } 150 151 unsigned int 152 decompress_kernel(void *output_start, 153 void *input_start, 154 size_t ksize, 155 size_t kzsize) 156 { 157 output_data = (uch *)output_start; 158 input_data = (uch *)input_start; 159 input_data_size = kzsize; /* use compressed size */ 160 161 /* FIXME FIXME FIXME */ 162 free_mem_ptr = (ulg)output_start + ksize; 163 free_mem_end_ptr = (ulg)output_start + ksize + 0x200000; 164 /* FIXME FIXME FIXME */ 165 166 /* put in temp area to reduce initial footprint */ 167 window = malloc(WSIZE); 168 169 makecrc(); 170 /* puts("Uncompressing Linux..."); */ 171 gunzip(); 172 /* puts(" done, booting the kernel.\n"); */ 173 return output_ptr; 174 } 175