LXR uboot/fs/zfs/zfs

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *  GRUB  --  GRand Unified Bootloader
   4 *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
   5 */
   6/*
   7 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   8 * Use is subject to license terms.
   9 */
  10
  11#include <common.h>
  12#include <malloc.h>
  13#include <linux/stat.h>
  14#include <linux/time.h>
  15#include <linux/ctype.h>
  16#include <asm/byteorder.h>
  17#include "zfs_common.h"
  18
  19#include <zfs/zfs.h>
  20#include <zfs/zio.h>
  21#include <zfs/dnode.h>
  22#include <zfs/uberblock_impl.h>
  23#include <zfs/vdev_impl.h>
  24#include <zfs/zio_checksum.h>
  25#include <zfs/zap_impl.h>
  26#include <zfs/zap_leaf.h>
  27#include <zfs/zfs_znode.h>
  28#include <zfs/dmu.h>
  29#include <zfs/dmu_objset.h>
  30#include <zfs/dsl_dir.h>
  31#include <zfs/dsl_dataset.h>
  32
  33#define MATCH_BITS      6
  34#define MATCH_MIN       3
  35#define OFFSET_MASK     ((1 << (16 - MATCH_BITS)) - 1)
  36
  37/*
  38 * Decompression Entry - lzjb
  39 */
  40#ifndef NBBY
  41#define NBBY    8
  42#endif
  43
  44int
  45lzjb_decompress(void *s_start, void *d_start, uint32_t s_len,
  46                                uint32_t d_len)
  47{
  48        uint8_t *src = s_start;
  49        uint8_t *dst = d_start;
  50        uint8_t *d_end = (uint8_t *) d_start + d_len;
  51        uint8_t *s_end = (uint8_t *) s_start + s_len;
  52        uint8_t *cpy, copymap = 0;
  53        int copymask = 1 << (NBBY - 1);
  54
  55        while (dst < d_end && src < s_end) {
  56                if ((copymask <<= 1) == (1 << NBBY)) {
  57                        copymask = 1;
  58                        copymap = *src++;
  59                }
  60                if (src >= s_end) {
  61                        printf("lzjb decompression failed\n");
  62                        return ZFS_ERR_BAD_FS;
  63                }
  64                if (copymap & copymask) {
  65                        int mlen = (src[0] >> (NBBY - MATCH_BITS)) + MATCH_MIN;
  66                        int offset = ((src[0] << NBBY) | src[1]) & OFFSET_MASK;
  67                        src += 2;
  68                        cpy = dst - offset;
  69                        if (src > s_end || cpy < (uint8_t *) d_start) {
  70                                printf("lzjb decompression failed\n");
  71                                return ZFS_ERR_BAD_FS;
  72                        }
  73                        while (--mlen >= 0 && dst < d_end)
  74                                *dst++ = *cpy++;
  75                } else {
  76                        *dst++ = *src++;
  77                }
  78        }
  79        if (dst < d_end) {
  80                printf("lzjb decompression failed\n");
  81                return ZFS_ERR_BAD_FS;
  82        }
  83        return ZFS_ERR_NONE;
  84}
  85