1 files changed, 379 insertions, 0 deletions

diff --git a/arch/i386/boot/compressed/misc_32.c b/arch/i386/boot/compressed/misc_32.c
new file mode 100644
index 000000000000..b28505c544c9
--- /dev/null
+++ b/arch/i386/boot/compressed/misc_32.c
@@ -0,0 +1,379 @@
+/*
+ * misc.c
+ * 
+ * This is a collection of several routines from gzip-1.0.3 
+ * adapted for Linux.
+ *
+ * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
+ * puts by Nick Holloway 1993, better puts by Martin Mares 1995
+ * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
+ */
+
+#undef CONFIG_PARAVIRT
+#include <linux/linkage.h>
+#include <linux/vmalloc.h>
+#include <linux/screen_info.h>
+#include <asm/io.h>
+#include <asm/page.h>
+#include <asm/boot.h>
+
+/* WARNING!!
+ * This code is compiled with -fPIC and it is relocated dynamically
+ * at run time, but no relocation processing is performed.
+ * This means that it is not safe to place pointers in static structures.
+ */
+
+/*
+ * Getting to provable safe in place decompression is hard.
+ * Worst case behaviours need to be analized.
+ * Background information:
+ *
+ * The file layout is:
+ *    magic[2]
+ *    method[1]
+ *    flags[1]
+ *    timestamp[4]
+ *    extraflags[1]
+ *    os[1]
+ *    compressed data blocks[N]
+ *    crc[4] orig_len[4]
+ *
+ * resulting in 18 bytes of non compressed data overhead.
+ *
+ * Files divided into blocks
+ * 1 bit (last block flag)
+ * 2 bits (block type)
+ *
+ * 1 block occurs every 32K -1 bytes or when there 50% compression has been achieved.
+ * The smallest block type encoding is always used.
+ *
+ * stored:
+ *    32 bits length in bytes.
+ *
+ * fixed:
+ *    magic fixed tree.
+ *    symbols.
+ *
+ * dynamic:
+ *    dynamic tree encoding.
+ *    symbols.
+ *
+ *
+ * The buffer for decompression in place is the length of the
+ * uncompressed data, plus a small amount extra to keep the algorithm safe.
+ * The compressed data is placed at the end of the buffer.  The output
+ * pointer is placed at the start of the buffer and the input pointer
+ * is placed where the compressed data starts.  Problems will occur
+ * when the output pointer overruns the input pointer.
+ *
+ * The output pointer can only overrun the input pointer if the input
+ * pointer is moving faster than the output pointer.  A condition only
+ * triggered by data whose compressed form is larger than the uncompressed
+ * form.
+ *
+ * The worst case at the block level is a growth of the compressed data
+ * of 5 bytes per 32767 bytes.
+ *
+ * The worst case internal to a compressed block is very hard to figure.
+ * The worst case can at least be boundined by having one bit that represents
+ * 32764 bytes and then all of the rest of the bytes representing the very
+ * very last byte.
+ *
+ * All of which is enough to compute an amount of extra data that is required
+ * to be safe.  To avoid problems at the block level allocating 5 extra bytes
+ * per 32767 bytes of data is sufficient.  To avoind problems internal to a block
+ * adding an extra 32767 bytes (the worst case uncompressed block size) is
+ * sufficient, to ensure that in the worst case the decompressed data for
+ * block will stop the byte before the compressed data for a block begins.
+ * To avoid problems with the compressed data's meta information an extra 18
+ * bytes are needed.  Leading to the formula:
+ *
+ * extra_bytes = (uncompressed_size >> 12) + 32768 + 18 + decompressor_size.
+ *
+ * Adding 8 bytes per 32K is a bit excessive but much easier to calculate.
+ * Adding 32768 instead of 32767 just makes for round numbers.
+ * Adding the decompressor_size is necessary as it musht live after all
+ * of the data as well.  Last I measured the decompressor is about 14K.
+ * 10K of actuall data and 4K of bss.
+ *
+ */
+
+/*
+ * gzip declarations
+ */
+
+#define OF(args)  args
+#define STATIC static
+
+#undef memset
+#undef memcpy
+#define memzero(s, n)     memset ((s), 0, (n))
+
+typedef unsigned char  uch;
+typedef unsigned short ush;
+typedef unsigned long  ulg;
+
+#define WSIZE 0x80000000        /* Window size must be at least 32k,
+                                 * and a power of two
+                                 * We don't actually have a window just
+                                 * a huge output buffer so I report
+                                 * a 2G windows size, as that should
+                                 * always be larger than our output buffer.
+                                 */
+
+static uch *inbuf;      /* input buffer */
+static uch *window;     /* Sliding window buffer, (and final output buffer) */
+
+static unsigned insize;  /* valid bytes in inbuf */
+static unsigned inptr;   /* index of next byte to be processed in inbuf */
+static unsigned outcnt;  /* bytes in output buffer */
+
+/* gzip flag byte */
+#define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
+#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
+#define EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
+#define ORIG_NAME    0x08 /* bit 3 set: original file name present */
+#define COMMENT      0x10 /* bit 4 set: file comment present */
+#define ENCRYPTED    0x20 /* bit 5 set: file is encrypted */
+#define RESERVED     0xC0 /* bit 6,7:   reserved */
+
+#define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
+                
+/* Diagnostic functions */
+#ifdef DEBUG
+#  define Assert(cond,msg) {if(!(cond)) error(msg);}
+#  define Trace(x) fprintf x
+#  define Tracev(x) {if (verbose) fprintf x ;}
+#  define Tracevv(x) {if (verbose>1) fprintf x ;}
+#  define Tracec(c,x) {if (verbose && (c)) fprintf x ;}
+#  define Tracecv(c,x) {if (verbose>1 && (c)) fprintf x ;}
+#else
+#  define Assert(cond,msg)
+#  define Trace(x)
+#  define Tracev(x)
+#  define Tracevv(x)
+#  define Tracec(c,x)
+#  define Tracecv(c,x)
+#endif
+
+static int  fill_inbuf(void);
+static void flush_window(void);
+static void error(char *m);
+static void gzip_mark(void **);
+static void gzip_release(void **);
+  
+/*
+ * This is set up by the setup-routine at boot-time
+ */
+static unsigned char *real_mode; /* Pointer to real-mode data */
+
+#define RM_EXT_MEM_K   (*(unsigned short *)(real_mode + 0x2))
+#ifndef STANDARD_MEMORY_BIOS_CALL
+#define RM_ALT_MEM_K   (*(unsigned long *)(real_mode + 0x1e0))
+#endif
+#define RM_SCREEN_INFO (*(struct screen_info *)(real_mode+0))
+
+extern unsigned char input_data[];
+extern int input_len;
+
+static long bytes_out = 0;
+
+static void *malloc(int size);
+static void free(void *where);
+
+static void *memset(void *s, int c, unsigned n);
+static void *memcpy(void *dest, const void *src, unsigned n);
+
+static void putstr(const char *);
+
+static unsigned long free_mem_ptr;
+static unsigned long free_mem_end_ptr;
+
+#define HEAP_SIZE             0x4000
+
+static char *vidmem = (char *)0xb8000;
+static int vidport;
+static int lines, cols;
+
+#ifdef CONFIG_X86_NUMAQ
+void *xquad_portio;
+#endif
+
+#include "../../../../lib/inflate.c"
+
+static void *malloc(int size)
+{
+        void *p;
+
+        if (size <0) error("Malloc error");
+        if (free_mem_ptr <= 0) error("Memory error");
+
+        free_mem_ptr = (free_mem_ptr + 3) & ~3; /* Align */
+
+        p = (void *)free_mem_ptr;
+        free_mem_ptr += size;
+
+        if (free_mem_ptr >= free_mem_end_ptr)
+                error("Out of memory");
+
+        return p;
+}
+
+static void free(void *where)
+{       /* Don't care */
+}
+
+static void gzip_mark(void **ptr)
+{
+        *ptr = (void *) free_mem_ptr;
+}
+
+static void gzip_release(void **ptr)
+{
+        free_mem_ptr = (unsigned long) *ptr;
+}
+ 
+static void scroll(void)
+{
+        int i;
+
+        memcpy ( vidmem, vidmem + cols * 2, ( lines - 1 ) * cols * 2 );
+        for ( i = ( lines - 1 ) * cols * 2; i < lines * cols * 2; i += 2 )
+                vidmem[i] = ' ';
+}
+
+static void putstr(const char *s)
+{
+        int x,y,pos;
+        char c;
+
+        x = RM_SCREEN_INFO.orig_x;
+        y = RM_SCREEN_INFO.orig_y;
+
+        while ( ( c = *s++ ) != '\0' ) {
+                if ( c == '\n' ) {
+                        x = 0;
+                        if ( ++y >= lines ) {
+                                scroll();
+                                y--;
+                        }
+                } else {
+                        vidmem [ ( x + cols * y ) * 2 ] = c;
+                        if ( ++x >= cols ) {
+                                x = 0;
+                                if ( ++y >= lines ) {
+                                        scroll();
+                                        y--;
+                                }
+                        }
+                }
+        }
+
+        RM_SCREEN_INFO.orig_x = x;
+        RM_SCREEN_INFO.orig_y = y;
+
+        pos = (x + cols * y) * 2;       /* Update cursor position */
+        outb_p(14, vidport);
+        outb_p(0xff & (pos >> 9), vidport+1);
+        outb_p(15, vidport);
+        outb_p(0xff & (pos >> 1), vidport+1);
+}
+
+static void* memset(void* s, int c, unsigned n)
+{
+        int i;
+        char *ss = (char*)s;
+
+        for (i=0;i<n;i++) ss[i] = c;
+        return s;
+}
+
+static void* memcpy(void* dest, const void* src, unsigned n)
+{
+        int i;
+        char *d = (char *)dest, *s = (char *)src;
+
+        for (i=0;i<n;i++) d[i] = s[i];
+        return dest;
+}
+
+/* ===========================================================================
+ * Fill the input buffer. This is called only when the buffer is empty
+ * and at least one byte is really needed.
+ */
+static int fill_inbuf(void)
+{
+        error("ran out of input data");
+        return 0;
+}
+
+/* ===========================================================================
+ * Write the output window window[0..outcnt-1] and update crc and bytes_out.
+ * (Used for the decompressed data only.)
+ */
+static void flush_window(void)
+{
+        /* With my window equal to my output buffer
+         * I only need to compute the crc here.
+         */
+        ulg c = crc;         /* temporary variable */
+        unsigned n;
+        uch *in, ch;
+
+        in = window;
+        for (n = 0; n < outcnt; n++) {
+                ch = *in++;
+                c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
+        }
+        crc = c;
+        bytes_out += (ulg)outcnt;
+        outcnt = 0;
+}
+
+static void error(char *x)
+{
+        putstr("\n\n");
+        putstr(x);
+        putstr("\n\n -- System halted");
+
+        while(1);       /* Halt */
+}
+
+asmlinkage void decompress_kernel(void *rmode, unsigned long end,
+                        uch *input_data, unsigned long input_len, uch *output)
+{
+        real_mode = rmode;
+
+        if (RM_SCREEN_INFO.orig_video_mode == 7) {
+                vidmem = (char *) 0xb0000;
+                vidport = 0x3b4;
+        } else {
+                vidmem = (char *) 0xb8000;
+                vidport = 0x3d4;
+        }
+
+        lines = RM_SCREEN_INFO.orig_video_lines;
+        cols = RM_SCREEN_INFO.orig_video_cols;
+
+        window = output;        /* Output buffer (Normally at 1M) */
+        free_mem_ptr     = end; /* Heap  */
+        free_mem_end_ptr = end + HEAP_SIZE;
+        inbuf  = input_data;    /* Input buffer */
+        insize = input_len;
+        inptr  = 0;
+
+        if ((u32)output & (CONFIG_PHYSICAL_ALIGN -1))
+                error("Destination address not CONFIG_PHYSICAL_ALIGN aligned");
+        if (end > ((-__PAGE_OFFSET-(512 <<20)-1) & 0x7fffffff))
+                error("Destination address too large");
+#ifndef CONFIG_RELOCATABLE
+        if ((u32)output != LOAD_PHYSICAL_ADDR)
+                error("Wrong destination address");
+#endif
+
+        makecrc();
+        putstr("Uncompressing Linux... ");
+        gunzip();
+        putstr("Ok, booting the kernel.\n");
+        return;
+}