| /* |
| * 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 |
| */ |
| |
| /* |
| * we have to be careful, because no indirections are allowed here, and |
| * paravirt_ops is a kind of one. As it will only run in baremetal anyway, |
| * we just keep it from happening |
| */ |
| #undef CONFIG_PARAVIRT |
| #ifdef CONFIG_X86_32 |
| #define _ASM_X86_DESC_H 1 |
| #endif |
| |
| #ifdef CONFIG_X86_64 |
| #define _LINUX_STRING_H_ 1 |
| #define __LINUX_BITMAP_H 1 |
| #endif |
| |
| #include <linux/linkage.h> |
| #include <linux/screen_info.h> |
| #include <linux/elf.h> |
| #include <linux/io.h> |
| #include <asm/page.h> |
| #include <asm/boot.h> |
| #include <asm/bootparam.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 analyzed. |
| * 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 actual 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; |
| |
| /* |
| * 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 we report a 2G window size, as that should always be |
| * larger than our output buffer: |
| */ |
| #define WSIZE 0x80000000 |
| |
| /* Input buffer: */ |
| static unsigned char *inbuf; |
| |
| /* Sliding window buffer (and final output buffer): */ |
| static unsigned char *window; |
| |
| /* Valid bytes in inbuf: */ |
| static unsigned insize; |
| |
| /* Index of next byte to be processed in inbuf: */ |
| static unsigned inptr; |
| |
| /* Bytes in output buffer: */ |
| static unsigned outcnt; |
| |
| /* gzip flag byte */ |
| #define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */ |
| #define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gz file */ |
| #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ |
| #define ORIG_NAM 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) do { if (!(cond)) error(msg); } while (0) |
| # define Trace(x) do { fprintf x; } while (0) |
| # define Tracev(x) do { if (verbose) fprintf x ; } while (0) |
| # define Tracevv(x) do { if (verbose > 1) fprintf x ; } while (0) |
| # define Tracec(c, x) do { if (verbose && (c)) fprintf x ; } while (0) |
| # define Tracecv(c, x) do { if (verbose > 1 && (c)) fprintf x ; } while (0) |
| #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); |
| |
| /* |
| * This is set up by the setup-routine at boot-time |
| */ |
| static struct boot_params *real_mode; /* Pointer to real-mode data */ |
| static int quiet; |
| |
| extern unsigned char input_data[]; |
| extern int input_len; |
| |
| static long bytes_out; |
| |
| static void *memset(void *s, int c, unsigned n); |
| static void *memcpy(void *dest, const void *src, unsigned n); |
| |
| static void __putstr(int, const char *); |
| #define putstr(__x) __putstr(0, __x) |
| |
| #ifdef CONFIG_X86_64 |
| #define memptr long |
| #else |
| #define memptr unsigned |
| #endif |
| |
| static memptr free_mem_ptr; |
| static memptr free_mem_end_ptr; |
| |
| static char *vidmem; |
| static int vidport; |
| static int lines, cols; |
| |
| #include "../../../../lib/inflate.c" |
| |
| 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(int error, const char *s) |
| { |
| int x, y, pos; |
| char c; |
| |
| #ifndef CONFIG_X86_VERBOSE_BOOTUP |
| if (!error) |
| return; |
| #endif |
| |
| #ifdef CONFIG_X86_32 |
| if (real_mode->screen_info.orig_video_mode == 0 && |
| lines == 0 && cols == 0) |
| return; |
| #endif |
| |
| x = real_mode->screen_info.orig_x; |
| y = real_mode->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--; |
| } |
| } |
| } |
| } |
| |
| real_mode->screen_info.orig_x = x; |
| real_mode->screen_info.orig_y = y; |
| |
| pos = (x + cols * y) * 2; /* Update cursor position */ |
| outb(14, vidport); |
| outb(0xff & (pos >> 9), vidport+1); |
| outb(15, vidport); |
| outb(0xff & (pos >> 1), vidport+1); |
| } |
| |
| static void *memset(void *s, int c, unsigned n) |
| { |
| int i; |
| char *ss = s; |
| |
| for (i = 0; i < n; i++) |
| ss[i] = c; |
| return s; |
| } |
| |
| static void *memcpy(void *dest, const void *src, unsigned n) |
| { |
| int i; |
| const char *s = src; |
| char *d = dest; |
| |
| 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. |
| */ |
| unsigned long c = crc; /* temporary variable */ |
| unsigned n; |
| unsigned char *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 += (unsigned long)outcnt; |
| outcnt = 0; |
| } |
| |
| static void error(char *x) |
| { |
| __putstr(1, "\n\n"); |
| __putstr(1, x); |
| __putstr(1, "\n\n -- System halted"); |
| |
| while (1) |
| asm("hlt"); |
| } |
| |
| static void parse_elf(void *output) |
| { |
| #ifdef CONFIG_X86_64 |
| Elf64_Ehdr ehdr; |
| Elf64_Phdr *phdrs, *phdr; |
| #else |
| Elf32_Ehdr ehdr; |
| Elf32_Phdr *phdrs, *phdr; |
| #endif |
| void *dest; |
| int i; |
| |
| memcpy(&ehdr, output, sizeof(ehdr)); |
| if (ehdr.e_ident[EI_MAG0] != ELFMAG0 || |
| ehdr.e_ident[EI_MAG1] != ELFMAG1 || |
| ehdr.e_ident[EI_MAG2] != ELFMAG2 || |
| ehdr.e_ident[EI_MAG3] != ELFMAG3) { |
| error("Kernel is not a valid ELF file"); |
| return; |
| } |
| |
| if (!quiet) |
| putstr("Parsing ELF... "); |
| |
| phdrs = malloc(sizeof(*phdrs) * ehdr.e_phnum); |
| if (!phdrs) |
| error("Failed to allocate space for phdrs"); |
| |
| memcpy(phdrs, output + ehdr.e_phoff, sizeof(*phdrs) * ehdr.e_phnum); |
| |
| for (i = 0; i < ehdr.e_phnum; i++) { |
| phdr = &phdrs[i]; |
| |
| switch (phdr->p_type) { |
| case PT_LOAD: |
| #ifdef CONFIG_RELOCATABLE |
| dest = output; |
| dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR); |
| #else |
| dest = (void *)(phdr->p_paddr); |
| #endif |
| memcpy(dest, |
| output + phdr->p_offset, |
| phdr->p_filesz); |
| break; |
| default: /* Ignore other PT_* */ break; |
| } |
| } |
| } |
| |
| asmlinkage void decompress_kernel(void *rmode, memptr heap, |
| unsigned char *input_data, |
| unsigned long input_len, |
| unsigned char *output) |
| { |
| real_mode = rmode; |
| |
| if (real_mode->hdr.loadflags & QUIET_FLAG) |
| quiet = 1; |
| |
| if (real_mode->screen_info.orig_video_mode == 7) { |
| vidmem = (char *) 0xb0000; |
| vidport = 0x3b4; |
| } else { |
| vidmem = (char *) 0xb8000; |
| vidport = 0x3d4; |
| } |
| |
| lines = real_mode->screen_info.orig_video_lines; |
| cols = real_mode->screen_info.orig_video_cols; |
| |
| window = output; /* Output buffer (Normally at 1M) */ |
| free_mem_ptr = heap; /* Heap */ |
| free_mem_end_ptr = heap + BOOT_HEAP_SIZE; |
| inbuf = input_data; /* Input buffer */ |
| insize = input_len; |
| inptr = 0; |
| |
| #ifdef CONFIG_X86_64 |
| if ((unsigned long)output & (__KERNEL_ALIGN - 1)) |
| error("Destination address not 2M aligned"); |
| if ((unsigned long)output >= 0xffffffffffUL) |
| error("Destination address too large"); |
| #else |
| if ((u32)output & (CONFIG_PHYSICAL_ALIGN - 1)) |
| error("Destination address not CONFIG_PHYSICAL_ALIGN aligned"); |
| if (heap > ((-__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 |
| #endif |
| |
| makecrc(); |
| if (!quiet) |
| putstr("\nDecompressing Linux... "); |
| gunzip(); |
| parse_elf(output); |
| if (!quiet) |
| putstr("done.\nBooting the kernel.\n"); |
| return; |
| } |