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1275 |
phoenix |
/*
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* Copyright (C) 1994-1997 Claus-Justus Heine
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This program is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2, or (at
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your option) any later version.
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This program is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; see the file COPYING. If not, write to
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the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
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USA.
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*
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* This file implements a "generic" interface between the *
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* zftape-driver and a compression-algorithm. The *
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* compression-algorithm currently used is a LZ77. I use the *
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* implementation lzrw3 by Ross N. Williams (Renaissance *
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* Software). The compression program itself is in the file
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* lzrw3.c * and lzrw3.h. To adopt another compression algorithm
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* the functions * zft_compress() and zft_uncompress() must be
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* changed * appropriately. See below.
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*/
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char zftc_src[] ="$Source: /home/marcus/revision_ctrl_test/oc_cvs/cvs/or1k/linux/linux-2.4/drivers/char/ftape/compressor/zftape-compress.c,v $";
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char zftc_rev[] = "$Revision: 1.1.1.1 $";
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char zftc_dat[] = "$Date: 2004-04-15 02:02:26 $";
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#include <linux/errno.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/zftape.h>
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#if LINUX_VERSION_CODE >= KERNEL_VER(2,1,6)
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#include <asm/uaccess.h>
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#else
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#include <asm/segment.h>
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#endif
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#include "../zftape/zftape-init.h"
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#include "../zftape/zftape-eof.h"
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#include "../zftape/zftape-ctl.h"
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#include "../zftape/zftape-write.h"
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#include "../zftape/zftape-read.h"
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#include "../zftape/zftape-rw.h"
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#include "../compressor/zftape-compress.h"
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#include "../zftape/zftape-vtbl.h"
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#include "../compressor/lzrw3.h"
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/*
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* global variables
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*/
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/* I handle the allocation of this buffer as a special case, because
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* it's size varies depending on the tape length inserted.
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*/
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/* local variables
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*/
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static int keep_module_locked = 1;
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static void *zftc_wrk_mem = NULL;
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static __u8 *zftc_buf = NULL;
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static void *zftc_scratch_buf = NULL;
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/* compression statistics
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*/
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static unsigned int zftc_wr_uncompressed = 0;
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static unsigned int zftc_wr_compressed = 0;
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static unsigned int zftc_rd_uncompressed = 0;
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static unsigned int zftc_rd_compressed = 0;
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/* forward */
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static int zftc_write(int *write_cnt,
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__u8 *dst_buf, const int seg_sz,
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const __u8 *src_buf, const int req_len,
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const zft_position *pos, const zft_volinfo *volume);
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static int zftc_read(int *read_cnt,
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__u8 *dst_buf, const int to_do,
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const __u8 *src_buf, const int seg_sz,
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const zft_position *pos, const zft_volinfo *volume);
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static int zftc_seek(unsigned int new_block_pos,
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zft_position *pos, const zft_volinfo *volume,
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__u8 *buffer);
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static void zftc_lock (void);
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static void zftc_reset (void);
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static void zftc_cleanup(void);
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static void zftc_stats (void);
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/* compressed segment. This conforms to QIC-80-MC, Revision K.
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*
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* Rev. K applies to tapes with `fixed length format' which is
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* indicated by format code 2,3 and 5. See below for format code 4 and 6
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*
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* 2 bytes: offset of compression segment structure
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* 29k > offset >= 29k-18: data from previous segment ens in this
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* segment and no compressed block starts
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* in this segment
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* offset == 0: data from previous segment occupies entire
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* segment and continues in next segment
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* n bytes: remainder from previous segment
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*
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* Rev. K:
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* 4 bytes: 4 bytes: files set byte offset
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* Post Rev. K and QIC-3020/3020:
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* 8 bytes: 8 bytes: files set byte offset
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* 2 bytes: byte count N (amount of data following)
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* bit 15 is set if data is compressed, bit 15 is not
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* set if data is uncompressed
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* N bytes: data (as much as specified in the byte count)
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* 2 bytes: byte count N_1 of next cluster
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* N_1 bytes: data of next cluset
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* 2 bytes: byte count N_2 of next cluster
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* N_2 bytes: ...
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*
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* Note that the `N' byte count accounts only for the bytes that in the
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* current segment if the cluster spans to the next segment.
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*/
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typedef struct
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{
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int cmpr_pos; /* actual position in compression buffer */
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int cmpr_sz; /* what is left in the compression buffer
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* when copying the compressed data to the
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* deblock buffer
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*/
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unsigned int first_block; /* location of header information in
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* this segment
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*/
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unsigned int count; /* amount of data of current block
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* contained in current segment
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*/
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unsigned int offset; /* offset in current segment */
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unsigned int spans:1; /* might continue in next segment */
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unsigned int uncmpr; /* 0x8000 if this block contains
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* uncompressed data
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*/
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__s64 foffs; /* file set byte offset, same as in
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* compression map segment
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*/
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} cmpr_info;
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static cmpr_info cseg; /* static data. Must be kept uptodate and shared by
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* read, write and seek functions
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*/
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#define DUMP_CMPR_INFO(level, msg, info) \
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TRACE(level, msg "\n" \
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KERN_INFO "cmpr_pos : %d\n" \
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KERN_INFO "cmpr_sz : %d\n" \
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KERN_INFO "first_block: %d\n" \
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KERN_INFO "count : %d\n" \
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KERN_INFO "offset : %d\n" \
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KERN_INFO "spans : %d\n" \
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KERN_INFO "uncmpr : 0x%04x\n" \
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KERN_INFO "foffs : " LL_X, \
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(info)->cmpr_pos, (info)->cmpr_sz, (info)->first_block, \
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(info)->count, (info)->offset, (info)->spans == 1, \
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(info)->uncmpr, LL((info)->foffs))
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/* dispatch compression segment info, return error code
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*
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* afterwards, cseg->offset points to start of data of the NEXT
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* compressed block, and cseg->count contains the amount of data
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* left in the actual compressed block. cseg->spans is set to 1 if
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* the block is continued in the following segment. Otherwise it is
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* set to 0.
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*/
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static int get_cseg (cmpr_info *cinfo, const __u8 *buff,
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const unsigned int seg_sz,
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const zft_volinfo *volume)
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{
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TRACE_FUN(ft_t_flow);
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cinfo->first_block = GET2(buff, 0);
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if (cinfo->first_block == 0) { /* data spans to next segment */
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cinfo->count = seg_sz - sizeof(__u16);
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cinfo->offset = seg_sz;
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cinfo->spans = 1;
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} else { /* cluster definetely ends in this segment */
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if (cinfo->first_block > seg_sz) {
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/* data corrupted */
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TRACE_ABORT(-EIO, ft_t_err, "corrupted data:\n"
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KERN_INFO "segment size: %d\n"
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KERN_INFO "first block : %d",
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seg_sz, cinfo->first_block);
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}
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cinfo->count = cinfo->first_block - sizeof(__u16);
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cinfo->offset = cinfo->first_block;
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cinfo->spans = 0;
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}
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/* now get the offset the first block should have in the
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* uncompressed data stream.
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*
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* For this magic `18' refer to CRF-3 standard or QIC-80MC,
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* Rev. K.
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*/
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if ((seg_sz - cinfo->offset) > 18) {
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if (volume->qic113) { /* > revision K */
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TRACE(ft_t_data_flow, "New QIC-113 compliance");
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cinfo->foffs = GET8(buff, cinfo->offset);
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cinfo->offset += sizeof(__s64);
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} else {
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TRACE(/* ft_t_data_flow */ ft_t_noise, "pre QIC-113 version");
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cinfo->foffs = (__s64)GET4(buff, cinfo->offset);
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cinfo->offset += sizeof(__u32);
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}
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}
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if (cinfo->foffs > volume->size) {
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TRACE_ABORT(-EIO, ft_t_err, "Inconsistency:\n"
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KERN_INFO "offset in current volume: %d\n"
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KERN_INFO "size of current volume : %d",
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(int)(cinfo->foffs>>10), (int)(volume->size>>10));
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}
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if (cinfo->cmpr_pos + cinfo->count > volume->blk_sz) {
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TRACE_ABORT(-EIO, ft_t_err, "Inconsistency:\n"
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KERN_INFO "block size : %d\n"
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KERN_INFO "data record: %d",
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volume->blk_sz, cinfo->cmpr_pos + cinfo->count);
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}
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DUMP_CMPR_INFO(ft_t_noise /* ft_t_any */, "", cinfo);
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TRACE_EXIT 0;
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}
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/* This one is called, when a new cluster starts in same segment.
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*
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* Note: if this is the first cluster in the current segment, we must
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* not check whether there are more than 18 bytes available because
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* this have already been done in get_cseg() and there may be less
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* than 18 bytes available due to header information.
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*
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*/
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static void get_next_cluster(cmpr_info *cluster, const __u8 *buff,
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const int seg_sz, const int finish)
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{
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TRACE_FUN(ft_t_flow);
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if (seg_sz - cluster->offset > 18 || cluster->foffs != 0) {
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cluster->count = GET2(buff, cluster->offset);
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cluster->uncmpr = cluster->count & 0x8000;
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cluster->count -= cluster->uncmpr;
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cluster->offset += sizeof(__u16);
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cluster->foffs = 0;
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if ((cluster->offset + cluster->count) < seg_sz) {
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cluster->spans = 0;
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} else if (cluster->offset + cluster->count == seg_sz) {
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cluster->spans = !finish;
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| 254 |
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} else {
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| 255 |
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/* either an error or a volume written by an
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* old version. If this is a data error, then we'll
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* catch it later.
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*/
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| 259 |
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TRACE(ft_t_data_flow, "Either error or old volume");
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cluster->spans = 1;
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cluster->count = seg_sz - cluster->offset;
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| 262 |
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}
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| 263 |
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} else {
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| 264 |
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cluster->count = 0;
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| 265 |
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cluster->spans = 0;
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| 266 |
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cluster->foffs = 0;
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| 267 |
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}
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| 268 |
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DUMP_CMPR_INFO(ft_t_noise /* ft_t_any */ , "", cluster);
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TRACE_EXIT;
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| 270 |
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}
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| 271 |
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| 272 |
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static void zftc_lock(void)
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| 273 |
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{
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| 274 |
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#if LINUX_VERSION_CODE < KERNEL_VER(2,1,18)
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| 275 |
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if (!MOD_IN_USE) {
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| 276 |
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MOD_INC_USE_COUNT;
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}
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| 278 |
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#else
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| 279 |
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MOD_INC_USE_COUNT; /* sets MOD_VISITED and MOD_USED_ONCE,
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| 280 |
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* locking is done with can_unload()
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| 281 |
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*/
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| 282 |
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#endif
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| 283 |
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keep_module_locked = 1;
|
| 284 |
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}
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| 285 |
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| 286 |
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/* this function is needed for zftape_reset_position in zftape-io.c
|
| 287 |
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*/
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| 288 |
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static void zftc_reset(void)
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| 289 |
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{
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| 290 |
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TRACE_FUN(ft_t_flow);
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| 291 |
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| 292 |
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memset((void *)&cseg, '\0', sizeof(cseg));
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| 293 |
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zftc_stats();
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| 294 |
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#if LINUX_VERSION_CODE < KERNEL_VER(2,1,18)
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| 295 |
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if (MOD_IN_USE) {
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| 296 |
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MOD_DEC_USE_COUNT;
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| 297 |
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}
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| 298 |
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#endif
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| 299 |
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keep_module_locked = 0;
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| 300 |
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TRACE_EXIT;
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| 301 |
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}
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| 302 |
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| 303 |
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static int cmpr_mem_initialized = 0;
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| 304 |
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static unsigned int alloc_blksz = 0;
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| 305 |
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| 306 |
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static int zft_allocate_cmpr_mem(unsigned int blksz)
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| 307 |
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{
|
| 308 |
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TRACE_FUN(ft_t_flow);
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| 309 |
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| 310 |
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if (cmpr_mem_initialized && blksz == alloc_blksz) {
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| 311 |
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TRACE_EXIT 0;
|
| 312 |
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}
|
| 313 |
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TRACE_CATCH(zft_vmalloc_once(&zftc_wrk_mem, CMPR_WRK_MEM_SIZE),
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| 314 |
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zftc_cleanup());
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| 315 |
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TRACE_CATCH(zft_vmalloc_always(&zftc_buf, blksz + CMPR_OVERRUN),
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| 316 |
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zftc_cleanup());
|
| 317 |
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alloc_blksz = blksz;
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| 318 |
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TRACE_CATCH(zft_vmalloc_always(&zftc_scratch_buf, blksz+CMPR_OVERRUN),
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| 319 |
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zftc_cleanup());
|
| 320 |
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cmpr_mem_initialized = 1;
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| 321 |
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TRACE_EXIT 0;
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| 322 |
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}
|
| 323 |
|
|
|
| 324 |
|
|
static void zftc_cleanup(void)
|
| 325 |
|
|
{
|
| 326 |
|
|
TRACE_FUN(ft_t_flow);
|
| 327 |
|
|
|
| 328 |
|
|
zft_vfree(&zftc_wrk_mem, CMPR_WRK_MEM_SIZE);
|
| 329 |
|
|
zft_vfree(&zftc_buf, alloc_blksz + CMPR_OVERRUN);
|
| 330 |
|
|
zft_vfree(&zftc_scratch_buf, alloc_blksz + CMPR_OVERRUN);
|
| 331 |
|
|
cmpr_mem_initialized = alloc_blksz = 0;
|
| 332 |
|
|
TRACE_EXIT;
|
| 333 |
|
|
}
|
| 334 |
|
|
|
| 335 |
|
|
/*****************************************************************************
|
| 336 |
|
|
* *
|
| 337 |
|
|
* The following two functions "ftape_compress()" and *
|
| 338 |
|
|
* "ftape_uncompress()" are the interface to the actual compression *
|
| 339 |
|
|
* algorithm (i.e. they are calling the "compress()" function from *
|
| 340 |
|
|
* the lzrw3 package for now). These routines could quite easily be *
|
| 341 |
|
|
* changed to adopt another compression algorithm instead of lzrw3, *
|
| 342 |
|
|
* which currently is used. *
|
| 343 |
|
|
* *
|
| 344 |
|
|
*****************************************************************************/
|
| 345 |
|
|
|
| 346 |
|
|
/* called by zft_compress_write() to perform the compression. Must
|
| 347 |
|
|
* return the size of the compressed data.
|
| 348 |
|
|
*
|
| 349 |
|
|
* NOTE: The size of the compressed data should not exceed the size of
|
| 350 |
|
|
* the uncompressed data. Most compression algorithms have means
|
| 351 |
|
|
* to store data unchanged if the "compressed" data amount would
|
| 352 |
|
|
* exceed the original one. Mostly this is done by storing some
|
| 353 |
|
|
* flag-bytes in front of the compressed data to indicate if it
|
| 354 |
|
|
* is compressed or not. Thus the worst compression result
|
| 355 |
|
|
* length is the original length plus those flag-bytes.
|
| 356 |
|
|
*
|
| 357 |
|
|
* We don't want that, as the QIC-80 standard provides a means
|
| 358 |
|
|
* of marking uncompressed blocks by simply setting bit 15 of
|
| 359 |
|
|
* the compressed block's length. Thus a compessed block can
|
| 360 |
|
|
* have at most a length of 2^15-1 bytes. The QIC-80 standard
|
| 361 |
|
|
* restricts the block-length even further, allowing only 29k -
|
| 362 |
|
|
* 6 bytes.
|
| 363 |
|
|
*
|
| 364 |
|
|
* Currently, the maximum blocksize used by zftape is 28k.
|
| 365 |
|
|
*
|
| 366 |
|
|
* In short: don't exceed the length of the input-package, set
|
| 367 |
|
|
* bit 15 of the compressed size to 1 if you have copied data
|
| 368 |
|
|
* instead of compressing it.
|
| 369 |
|
|
*/
|
| 370 |
|
|
static int zft_compress(__u8 *in_buffer, unsigned int in_sz, __u8 *out_buffer)
|
| 371 |
|
|
{
|
| 372 |
|
|
__s32 compressed_sz;
|
| 373 |
|
|
TRACE_FUN(ft_t_flow);
|
| 374 |
|
|
|
| 375 |
|
|
|
| 376 |
|
|
lzrw3_compress(COMPRESS_ACTION_COMPRESS, zftc_wrk_mem,
|
| 377 |
|
|
in_buffer, in_sz, out_buffer, &compressed_sz);
|
| 378 |
|
|
if (TRACE_LEVEL >= ft_t_info) {
|
| 379 |
|
|
/* the compiler will optimize this away when
|
| 380 |
|
|
* compiled with NO_TRACE_AT_ALL option
|
| 381 |
|
|
*/
|
| 382 |
|
|
TRACE(ft_t_data_flow, "\n"
|
| 383 |
|
|
KERN_INFO "before compression: %d bytes\n"
|
| 384 |
|
|
KERN_INFO "after compresison : %d bytes",
|
| 385 |
|
|
in_sz,
|
| 386 |
|
|
(int)(compressed_sz < 0
|
| 387 |
|
|
? -compressed_sz : compressed_sz));
|
| 388 |
|
|
/* for statistical purposes
|
| 389 |
|
|
*/
|
| 390 |
|
|
zftc_wr_compressed += (compressed_sz < 0
|
| 391 |
|
|
? -compressed_sz : compressed_sz);
|
| 392 |
|
|
zftc_wr_uncompressed += in_sz;
|
| 393 |
|
|
}
|
| 394 |
|
|
TRACE_EXIT (int)compressed_sz;
|
| 395 |
|
|
}
|
| 396 |
|
|
|
| 397 |
|
|
/* called by zft_compress_read() to decompress the data. Must
|
| 398 |
|
|
* return the size of the decompressed data for sanity checks
|
| 399 |
|
|
* (compared with zft_blk_sz)
|
| 400 |
|
|
*
|
| 401 |
|
|
* NOTE: Read the note for zft_compress() above! If bit 15 of the
|
| 402 |
|
|
* parameter in_sz is set, then the data in in_buffer isn't
|
| 403 |
|
|
* compressed, which must be handled by the un-compression
|
| 404 |
|
|
* algorithm. (I changed lzrw3 to handle this.)
|
| 405 |
|
|
*
|
| 406 |
|
|
* The parameter max_out_sz is needed to prevent buffer overruns when
|
| 407 |
|
|
* uncompressing corrupt data.
|
| 408 |
|
|
*/
|
| 409 |
|
|
static unsigned int zft_uncompress(__u8 *in_buffer,
|
| 410 |
|
|
int in_sz,
|
| 411 |
|
|
__u8 *out_buffer,
|
| 412 |
|
|
unsigned int max_out_sz)
|
| 413 |
|
|
{
|
| 414 |
|
|
TRACE_FUN(ft_t_flow);
|
| 415 |
|
|
|
| 416 |
|
|
lzrw3_compress(COMPRESS_ACTION_DECOMPRESS, zftc_wrk_mem,
|
| 417 |
|
|
in_buffer, (__s32)in_sz,
|
| 418 |
|
|
out_buffer, (__u32 *)&max_out_sz);
|
| 419 |
|
|
|
| 420 |
|
|
if (TRACE_LEVEL >= ft_t_info) {
|
| 421 |
|
|
TRACE(ft_t_data_flow, "\n"
|
| 422 |
|
|
KERN_INFO "before decompression: %d bytes\n"
|
| 423 |
|
|
KERN_INFO "after decompression : %d bytes",
|
| 424 |
|
|
in_sz < 0 ? -in_sz : in_sz,(int)max_out_sz);
|
| 425 |
|
|
/* for statistical purposes
|
| 426 |
|
|
*/
|
| 427 |
|
|
zftc_rd_compressed += in_sz < 0 ? -in_sz : in_sz;
|
| 428 |
|
|
zftc_rd_uncompressed += max_out_sz;
|
| 429 |
|
|
}
|
| 430 |
|
|
TRACE_EXIT (unsigned int)max_out_sz;
|
| 431 |
|
|
}
|
| 432 |
|
|
|
| 433 |
|
|
/* print some statistics about the efficiency of the compression to
|
| 434 |
|
|
* the kernel log
|
| 435 |
|
|
*/
|
| 436 |
|
|
static void zftc_stats(void)
|
| 437 |
|
|
{
|
| 438 |
|
|
TRACE_FUN(ft_t_flow);
|
| 439 |
|
|
|
| 440 |
|
|
if (TRACE_LEVEL < ft_t_info) {
|
| 441 |
|
|
TRACE_EXIT;
|
| 442 |
|
|
}
|
| 443 |
|
|
if (zftc_wr_uncompressed != 0) {
|
| 444 |
|
|
if (zftc_wr_compressed > (1<<14)) {
|
| 445 |
|
|
TRACE(ft_t_info, "compression statistics (writing):\n"
|
| 446 |
|
|
KERN_INFO " compr./uncmpr. : %3d %%",
|
| 447 |
|
|
(((zftc_wr_compressed>>10) * 100)
|
| 448 |
|
|
/ (zftc_wr_uncompressed>>10)));
|
| 449 |
|
|
} else {
|
| 450 |
|
|
TRACE(ft_t_info, "compression statistics (writing):\n"
|
| 451 |
|
|
KERN_INFO " compr./uncmpr. : %3d %%",
|
| 452 |
|
|
((zftc_wr_compressed * 100)
|
| 453 |
|
|
/ zftc_wr_uncompressed));
|
| 454 |
|
|
}
|
| 455 |
|
|
}
|
| 456 |
|
|
if (zftc_rd_uncompressed != 0) {
|
| 457 |
|
|
if (zftc_rd_compressed > (1<<14)) {
|
| 458 |
|
|
TRACE(ft_t_info, "compression statistics (reading):\n"
|
| 459 |
|
|
KERN_INFO " compr./uncmpr. : %3d %%",
|
| 460 |
|
|
(((zftc_rd_compressed>>10) * 100)
|
| 461 |
|
|
/ (zftc_rd_uncompressed>>10)));
|
| 462 |
|
|
} else {
|
| 463 |
|
|
TRACE(ft_t_info, "compression statistics (reading):\n"
|
| 464 |
|
|
KERN_INFO " compr./uncmpr. : %3d %%",
|
| 465 |
|
|
((zftc_rd_compressed * 100)
|
| 466 |
|
|
/ zftc_rd_uncompressed));
|
| 467 |
|
|
}
|
| 468 |
|
|
}
|
| 469 |
|
|
/* only print it once: */
|
| 470 |
|
|
zftc_wr_uncompressed =
|
| 471 |
|
|
zftc_wr_compressed =
|
| 472 |
|
|
zftc_rd_uncompressed =
|
| 473 |
|
|
zftc_rd_compressed = 0;
|
| 474 |
|
|
TRACE_EXIT;
|
| 475 |
|
|
}
|
| 476 |
|
|
|
| 477 |
|
|
/* start new compressed block
|
| 478 |
|
|
*/
|
| 479 |
|
|
static int start_new_cseg(cmpr_info *cluster,
|
| 480 |
|
|
char *dst_buf,
|
| 481 |
|
|
const zft_position *pos,
|
| 482 |
|
|
const unsigned int blk_sz,
|
| 483 |
|
|
const char *src_buf,
|
| 484 |
|
|
const int this_segs_sz,
|
| 485 |
|
|
const int qic113)
|
| 486 |
|
|
{
|
| 487 |
|
|
int size_left;
|
| 488 |
|
|
int cp_cnt;
|
| 489 |
|
|
int buf_pos;
|
| 490 |
|
|
TRACE_FUN(ft_t_flow);
|
| 491 |
|
|
|
| 492 |
|
|
size_left = this_segs_sz - sizeof(__u16) - cluster->cmpr_sz;
|
| 493 |
|
|
TRACE(ft_t_data_flow,"\n"
|
| 494 |
|
|
KERN_INFO "segment size : %d\n"
|
| 495 |
|
|
KERN_INFO "compressed_sz: %d\n"
|
| 496 |
|
|
KERN_INFO "size_left : %d",
|
| 497 |
|
|
this_segs_sz, cluster->cmpr_sz, size_left);
|
| 498 |
|
|
if (size_left > 18) { /* start a new cluseter */
|
| 499 |
|
|
cp_cnt = cluster->cmpr_sz;
|
| 500 |
|
|
cluster->cmpr_sz = 0;
|
| 501 |
|
|
buf_pos = cp_cnt + sizeof(__u16);
|
| 502 |
|
|
PUT2(dst_buf, 0, buf_pos);
|
| 503 |
|
|
|
| 504 |
|
|
if (qic113) {
|
| 505 |
|
|
__s64 foffs = pos->volume_pos;
|
| 506 |
|
|
if (cp_cnt) foffs += (__s64)blk_sz;
|
| 507 |
|
|
|
| 508 |
|
|
TRACE(ft_t_data_flow, "new style QIC-113 header");
|
| 509 |
|
|
PUT8(dst_buf, buf_pos, foffs);
|
| 510 |
|
|
buf_pos += sizeof(__s64);
|
| 511 |
|
|
} else {
|
| 512 |
|
|
__u32 foffs = (__u32)pos->volume_pos;
|
| 513 |
|
|
if (cp_cnt) foffs += (__u32)blk_sz;
|
| 514 |
|
|
|
| 515 |
|
|
TRACE(ft_t_data_flow, "old style QIC-80MC header");
|
| 516 |
|
|
PUT4(dst_buf, buf_pos, foffs);
|
| 517 |
|
|
buf_pos += sizeof(__u32);
|
| 518 |
|
|
}
|
| 519 |
|
|
} else if (size_left >= 0) {
|
| 520 |
|
|
cp_cnt = cluster->cmpr_sz;
|
| 521 |
|
|
cluster->cmpr_sz = 0;
|
| 522 |
|
|
buf_pos = cp_cnt + sizeof(__u16);
|
| 523 |
|
|
PUT2(dst_buf, 0, buf_pos);
|
| 524 |
|
|
/* zero unused part of segment. */
|
| 525 |
|
|
memset(dst_buf + buf_pos, '\0', size_left);
|
| 526 |
|
|
buf_pos = this_segs_sz;
|
| 527 |
|
|
} else { /* need entire segment and more space */
|
| 528 |
|
|
PUT2(dst_buf, 0, 0);
|
| 529 |
|
|
cp_cnt = this_segs_sz - sizeof(__u16);
|
| 530 |
|
|
cluster->cmpr_sz -= cp_cnt;
|
| 531 |
|
|
buf_pos = this_segs_sz;
|
| 532 |
|
|
}
|
| 533 |
|
|
memcpy(dst_buf + sizeof(__u16), src_buf + cluster->cmpr_pos, cp_cnt);
|
| 534 |
|
|
cluster->cmpr_pos += cp_cnt;
|
| 535 |
|
|
TRACE_EXIT buf_pos;
|
| 536 |
|
|
}
|
| 537 |
|
|
|
| 538 |
|
|
/* return-value: the number of bytes removed from the user-buffer
|
| 539 |
|
|
* `src_buf' or error code
|
| 540 |
|
|
*
|
| 541 |
|
|
* int *write_cnt : how much actually has been moved to the
|
| 542 |
|
|
* dst_buf. Need not be initialized when
|
| 543 |
|
|
* function returns with an error code
|
| 544 |
|
|
* (negativ return value)
|
| 545 |
|
|
* __u8 *dst_buf : kernel space buffer where the has to be
|
| 546 |
|
|
* copied to. The contents of this buffers
|
| 547 |
|
|
* goes to a specific segment.
|
| 548 |
|
|
* const int seg_sz : the size of the segment dst_buf will be
|
| 549 |
|
|
* copied to.
|
| 550 |
|
|
* const zft_position *pos : struct containing the coordinates in
|
| 551 |
|
|
* the current volume (byte position,
|
| 552 |
|
|
* segment id of current segment etc)
|
| 553 |
|
|
* const zft_volinfo *volume: information about the current volume,
|
| 554 |
|
|
* size etc.
|
| 555 |
|
|
* const __u8 *src_buf : user space buffer that contains the
|
| 556 |
|
|
* data the user wants to be written to
|
| 557 |
|
|
* tape.
|
| 558 |
|
|
* const int req_len : the amount of data the user wants to be
|
| 559 |
|
|
* written to tape.
|
| 560 |
|
|
*/
|
| 561 |
|
|
static int zftc_write(int *write_cnt,
|
| 562 |
|
|
__u8 *dst_buf, const int seg_sz,
|
| 563 |
|
|
const __u8 *src_buf, const int req_len,
|
| 564 |
|
|
const zft_position *pos, const zft_volinfo *volume)
|
| 565 |
|
|
{
|
| 566 |
|
|
int req_len_left = req_len;
|
| 567 |
|
|
int result;
|
| 568 |
|
|
int len_left;
|
| 569 |
|
|
int buf_pos_write = pos->seg_byte_pos;
|
| 570 |
|
|
TRACE_FUN(ft_t_flow);
|
| 571 |
|
|
|
| 572 |
|
|
keep_module_locked = 1;
|
| 573 |
|
|
#if LINUX_VERSION_CODE >= KERNEL_VER(2,1,18)
|
| 574 |
|
|
MOD_INC_USE_COUNT; /* sets MOD_VISITED and MOD_USED_ONCE,
|
| 575 |
|
|
* locking is done with can_unload()
|
| 576 |
|
|
*/
|
| 577 |
|
|
#else
|
| 578 |
|
|
if (!MOD_IN_USE) {
|
| 579 |
|
|
MOD_INC_USE_COUNT;
|
| 580 |
|
|
}
|
| 581 |
|
|
#endif
|
| 582 |
|
|
/* Note: we do not unlock the module because
|
| 583 |
|
|
* there are some values cached in that `cseg' variable. We
|
| 584 |
|
|
* don't don't want to use this information when being
|
| 585 |
|
|
* unloaded by kerneld even when the tape is full or when we
|
| 586 |
|
|
* cannot allocate enough memory.
|
| 587 |
|
|
*/
|
| 588 |
|
|
if (pos->tape_pos > (volume->size-volume->blk_sz-ZFT_CMPR_OVERHEAD)) {
|
| 589 |
|
|
TRACE_EXIT -ENOSPC;
|
| 590 |
|
|
}
|
| 591 |
|
|
if (zft_allocate_cmpr_mem(volume->blk_sz) < 0) {
|
| 592 |
|
|
/* should we unlock the module? But it shouldn't
|
| 593 |
|
|
* be locked anyway ...
|
| 594 |
|
|
*/
|
| 595 |
|
|
TRACE_EXIT -ENOMEM;
|
| 596 |
|
|
}
|
| 597 |
|
|
if (buf_pos_write == 0) { /* fill a new segment */
|
| 598 |
|
|
*write_cnt = buf_pos_write = start_new_cseg(&cseg,
|
| 599 |
|
|
dst_buf,
|
| 600 |
|
|
pos,
|
| 601 |
|
|
volume->blk_sz,
|
| 602 |
|
|
zftc_buf,
|
| 603 |
|
|
seg_sz,
|
| 604 |
|
|
volume->qic113);
|
| 605 |
|
|
if (cseg.cmpr_sz == 0 && cseg.cmpr_pos != 0) {
|
| 606 |
|
|
req_len_left -= result = volume->blk_sz;
|
| 607 |
|
|
cseg.cmpr_pos = 0;
|
| 608 |
|
|
} else {
|
| 609 |
|
|
result = 0;
|
| 610 |
|
|
}
|
| 611 |
|
|
} else {
|
| 612 |
|
|
*write_cnt = result = 0;
|
| 613 |
|
|
}
|
| 614 |
|
|
|
| 615 |
|
|
len_left = seg_sz - buf_pos_write;
|
| 616 |
|
|
while ((req_len_left > 0) && (len_left > 18)) {
|
| 617 |
|
|
/* now we have some size left for a new compressed
|
| 618 |
|
|
* block. We know, that the compression buffer is
|
| 619 |
|
|
* empty (else there wouldn't be any space left).
|
| 620 |
|
|
*/
|
| 621 |
|
|
#if LINUX_VERSION_CODE > KERNEL_VER(2,1,3)
|
| 622 |
|
|
if (copy_from_user(zftc_scratch_buf, src_buf + result,
|
| 623 |
|
|
volume->blk_sz) != 0) {
|
| 624 |
|
|
TRACE_EXIT -EFAULT;
|
| 625 |
|
|
}
|
| 626 |
|
|
#else
|
| 627 |
|
|
TRACE_CATCH(verify_area(VERIFY_READ, src_buf + result,
|
| 628 |
|
|
volume->blk_sz),);
|
| 629 |
|
|
memcpy_fromfs(zftc_scratch_buf, src_buf + result,
|
| 630 |
|
|
volume->blk_sz);
|
| 631 |
|
|
#endif
|
| 632 |
|
|
req_len_left -= volume->blk_sz;
|
| 633 |
|
|
cseg.cmpr_sz = zft_compress(zftc_scratch_buf, volume->blk_sz,
|
| 634 |
|
|
zftc_buf);
|
| 635 |
|
|
if (cseg.cmpr_sz < 0) {
|
| 636 |
|
|
cseg.uncmpr = 0x8000;
|
| 637 |
|
|
cseg.cmpr_sz = -cseg.cmpr_sz;
|
| 638 |
|
|
} else {
|
| 639 |
|
|
cseg.uncmpr = 0;
|
| 640 |
|
|
}
|
| 641 |
|
|
/* increment "result" iff we copied the entire
|
| 642 |
|
|
* compressed block to the zft_deblock_buf
|
| 643 |
|
|
*/
|
| 644 |
|
|
len_left -= sizeof(__u16);
|
| 645 |
|
|
if (len_left >= cseg.cmpr_sz) {
|
| 646 |
|
|
len_left -= cseg.count = cseg.cmpr_sz;
|
| 647 |
|
|
cseg.cmpr_pos = cseg.cmpr_sz = 0;
|
| 648 |
|
|
result += volume->blk_sz;
|
| 649 |
|
|
} else {
|
| 650 |
|
|
cseg.cmpr_sz -=
|
| 651 |
|
|
cseg.cmpr_pos =
|
| 652 |
|
|
cseg.count = len_left;
|
| 653 |
|
|
len_left = 0;
|
| 654 |
|
|
}
|
| 655 |
|
|
PUT2(dst_buf, buf_pos_write, cseg.uncmpr | cseg.count);
|
| 656 |
|
|
buf_pos_write += sizeof(__u16);
|
| 657 |
|
|
memcpy(dst_buf + buf_pos_write, zftc_buf, cseg.count);
|
| 658 |
|
|
buf_pos_write += cseg.count;
|
| 659 |
|
|
*write_cnt += cseg.count + sizeof(__u16);
|
| 660 |
|
|
FT_SIGNAL_EXIT(_DONT_BLOCK);
|
| 661 |
|
|
}
|
| 662 |
|
|
/* erase the remainder of the segment if less than 18 bytes
|
| 663 |
|
|
* left (18 bytes is due to the QIC-80 standard)
|
| 664 |
|
|
*/
|
| 665 |
|
|
if (len_left <= 18) {
|
| 666 |
|
|
memset(dst_buf + buf_pos_write, '\0', len_left);
|
| 667 |
|
|
(*write_cnt) += len_left;
|
| 668 |
|
|
}
|
| 669 |
|
|
TRACE(ft_t_data_flow, "returning %d", result);
|
| 670 |
|
|
TRACE_EXIT result;
|
| 671 |
|
|
}
|
| 672 |
|
|
|
| 673 |
|
|
/* out:
|
| 674 |
|
|
*
|
| 675 |
|
|
* int *read_cnt: the number of bytes we removed from the zft_deblock_buf
|
| 676 |
|
|
* (result)
|
| 677 |
|
|
* int *to_do : the remaining size of the read-request.
|
| 678 |
|
|
*
|
| 679 |
|
|
* in:
|
| 680 |
|
|
*
|
| 681 |
|
|
* char *buff : buff is the address of the upper part of the user
|
| 682 |
|
|
* buffer, that hasn't been filled with data yet.
|
| 683 |
|
|
|
| 684 |
|
|
* int buf_pos_read : copy of from _ftape_read()
|
| 685 |
|
|
* int buf_len_read : copy of buf_len_rd from _ftape_read()
|
| 686 |
|
|
* char *zft_deblock_buf: zft_deblock_buf
|
| 687 |
|
|
* unsigned short blk_sz: the block size valid for this volume, may differ
|
| 688 |
|
|
* from zft_blk_sz.
|
| 689 |
|
|
* int finish: if != 0 means that this is the last segment belonging
|
| 690 |
|
|
* to this volume
|
| 691 |
|
|
* returns the amount of data actually copied to the user-buffer
|
| 692 |
|
|
*
|
| 693 |
|
|
* to_do MUST NOT SHRINK except to indicate an EOF. In this case *to_do has to
|
| 694 |
|
|
* be set to 0
|
| 695 |
|
|
*/
|
| 696 |
|
|
static int zftc_read (int *read_cnt,
|
| 697 |
|
|
__u8 *dst_buf, const int to_do,
|
| 698 |
|
|
const __u8 *src_buf, const int seg_sz,
|
| 699 |
|
|
const zft_position *pos, const zft_volinfo *volume)
|
| 700 |
|
|
{
|
| 701 |
|
|
int uncompressed_sz;
|
| 702 |
|
|
int result = 0;
|
| 703 |
|
|
int remaining = to_do;
|
| 704 |
|
|
TRACE_FUN(ft_t_flow);
|
| 705 |
|
|
|
| 706 |
|
|
keep_module_locked = 1;
|
| 707 |
|
|
#if LINUX_VERSION_CODE >= KERNEL_VER(2,1,18)
|
| 708 |
|
|
MOD_INC_USE_COUNT; /* sets MOD_VISITED and MOD_USED_ONCE,
|
| 709 |
|
|
* locking is done with can_unload()
|
| 710 |
|
|
*/
|
| 711 |
|
|
#else
|
| 712 |
|
|
if (!MOD_IN_USE) {
|
| 713 |
|
|
MOD_INC_USE_COUNT;
|
| 714 |
|
|
}
|
| 715 |
|
|
#endif
|
| 716 |
|
|
TRACE_CATCH(zft_allocate_cmpr_mem(volume->blk_sz),);
|
| 717 |
|
|
if (pos->seg_byte_pos == 0) {
|
| 718 |
|
|
/* new segment just read
|
| 719 |
|
|
*/
|
| 720 |
|
|
TRACE_CATCH(get_cseg(&cseg, src_buf, seg_sz, volume),
|
| 721 |
|
|
*read_cnt = 0);
|
| 722 |
|
|
memcpy(zftc_buf + cseg.cmpr_pos, src_buf + sizeof(__u16),
|
| 723 |
|
|
cseg.count);
|
| 724 |
|
|
cseg.cmpr_pos += cseg.count;
|
| 725 |
|
|
*read_cnt = cseg.offset;
|
| 726 |
|
|
DUMP_CMPR_INFO(ft_t_noise /* ft_t_any */, "", &cseg);
|
| 727 |
|
|
} else {
|
| 728 |
|
|
*read_cnt = 0;
|
| 729 |
|
|
}
|
| 730 |
|
|
/* loop and uncompress until user buffer full or
|
| 731 |
|
|
* deblock-buffer empty
|
| 732 |
|
|
*/
|
| 733 |
|
|
TRACE(ft_t_data_flow, "compressed_sz: %d, compos : %d, *read_cnt: %d",
|
| 734 |
|
|
cseg.cmpr_sz, cseg.cmpr_pos, *read_cnt);
|
| 735 |
|
|
while ((cseg.spans == 0) && (remaining > 0)) {
|
| 736 |
|
|
if (cseg.cmpr_pos != 0) { /* cmpr buf is not empty */
|
| 737 |
|
|
uncompressed_sz =
|
| 738 |
|
|
zft_uncompress(zftc_buf,
|
| 739 |
|
|
cseg.uncmpr == 0x8000 ?
|
| 740 |
|
|
-cseg.cmpr_pos : cseg.cmpr_pos,
|
| 741 |
|
|
zftc_scratch_buf,
|
| 742 |
|
|
volume->blk_sz);
|
| 743 |
|
|
if (uncompressed_sz != volume->blk_sz) {
|
| 744 |
|
|
*read_cnt = 0;
|
| 745 |
|
|
TRACE_ABORT(-EIO, ft_t_warn,
|
| 746 |
|
|
"Uncompressed blk (%d) != blk size (%d)",
|
| 747 |
|
|
uncompressed_sz, volume->blk_sz);
|
| 748 |
|
|
}
|
| 749 |
|
|
#if LINUX_VERSION_CODE > KERNEL_VER(2,1,3)
|
| 750 |
|
|
if (copy_to_user(dst_buf + result,
|
| 751 |
|
|
zftc_scratch_buf,
|
| 752 |
|
|
uncompressed_sz) != 0 ) {
|
| 753 |
|
|
TRACE_EXIT -EFAULT;
|
| 754 |
|
|
}
|
| 755 |
|
|
#else
|
| 756 |
|
|
memcpy_tofs(dst_buf + result, zftc_scratch_buf,
|
| 757 |
|
|
uncompressed_sz);
|
| 758 |
|
|
#endif
|
| 759 |
|
|
remaining -= uncompressed_sz;
|
| 760 |
|
|
result += uncompressed_sz;
|
| 761 |
|
|
cseg.cmpr_pos = 0;
|
| 762 |
|
|
}
|
| 763 |
|
|
if (remaining > 0) {
|
| 764 |
|
|
get_next_cluster(&cseg, src_buf, seg_sz,
|
| 765 |
|
|
volume->end_seg == pos->seg_pos);
|
| 766 |
|
|
if (cseg.count != 0) {
|
| 767 |
|
|
memcpy(zftc_buf, src_buf + cseg.offset,
|
| 768 |
|
|
cseg.count);
|
| 769 |
|
|
cseg.cmpr_pos = cseg.count;
|
| 770 |
|
|
cseg.offset += cseg.count;
|
| 771 |
|
|
*read_cnt += cseg.count + sizeof(__u16);
|
| 772 |
|
|
} else {
|
| 773 |
|
|
remaining = 0;
|
| 774 |
|
|
}
|
| 775 |
|
|
}
|
| 776 |
|
|
TRACE(ft_t_data_flow, "\n"
|
| 777 |
|
|
KERN_INFO "compressed_sz: %d\n"
|
| 778 |
|
|
KERN_INFO "compos : %d\n"
|
| 779 |
|
|
KERN_INFO "*read_cnt : %d",
|
| 780 |
|
|
cseg.cmpr_sz, cseg.cmpr_pos, *read_cnt);
|
| 781 |
|
|
}
|
| 782 |
|
|
if (seg_sz - cseg.offset <= 18) {
|
| 783 |
|
|
*read_cnt += seg_sz - cseg.offset;
|
| 784 |
|
|
TRACE(ft_t_data_flow, "expanding read cnt to: %d", *read_cnt);
|
| 785 |
|
|
}
|
| 786 |
|
|
TRACE(ft_t_data_flow, "\n"
|
| 787 |
|
|
KERN_INFO "segment size : %d\n"
|
| 788 |
|
|
KERN_INFO "read count : %d\n"
|
| 789 |
|
|
KERN_INFO "buf_pos_read : %d\n"
|
| 790 |
|
|
KERN_INFO "remaining : %d",
|
| 791 |
|
|
seg_sz, *read_cnt, pos->seg_byte_pos,
|
| 792 |
|
|
seg_sz - *read_cnt - pos->seg_byte_pos);
|
| 793 |
|
|
TRACE(ft_t_data_flow, "returning: %d", result);
|
| 794 |
|
|
TRACE_EXIT result;
|
| 795 |
|
|
}
|
| 796 |
|
|
|
| 797 |
|
|
/* seeks to the new data-position. Reads sometimes a segment.
|
| 798 |
|
|
*
|
| 799 |
|
|
* start_seg and end_seg give the boundaries of the current volume
|
| 800 |
|
|
* blk_sz is the blk_sz of the current volume as stored in the
|
| 801 |
|
|
* volume label
|
| 802 |
|
|
*
|
| 803 |
|
|
* We don't allow blocksizes less than 1024 bytes, therefore we don't need
|
| 804 |
|
|
* a 64 bit argument for new_block_pos.
|
| 805 |
|
|
*/
|
| 806 |
|
|
|
| 807 |
|
|
static int seek_in_segment(const unsigned int to_do, cmpr_info *c_info,
|
| 808 |
|
|
const char *src_buf, const int seg_sz,
|
| 809 |
|
|
const int seg_pos, const zft_volinfo *volume);
|
| 810 |
|
|
static int slow_seek_forward_until_error(const unsigned int distance,
|
| 811 |
|
|
cmpr_info *c_info, zft_position *pos,
|
| 812 |
|
|
const zft_volinfo *volume, __u8 *buf);
|
| 813 |
|
|
static int search_valid_segment(unsigned int segment,
|
| 814 |
|
|
const unsigned int end_seg,
|
| 815 |
|
|
const unsigned int max_foffs,
|
| 816 |
|
|
zft_position *pos, cmpr_info *c_info,
|
| 817 |
|
|
const zft_volinfo *volume, __u8 *buf);
|
| 818 |
|
|
static int slow_seek_forward(unsigned int dest, cmpr_info *c_info,
|
| 819 |
|
|
zft_position *pos, const zft_volinfo *volume,
|
| 820 |
|
|
__u8 *buf);
|
| 821 |
|
|
static int compute_seg_pos(unsigned int dest, zft_position *pos,
|
| 822 |
|
|
const zft_volinfo *volume);
|
| 823 |
|
|
|
| 824 |
|
|
#define ZFT_SLOW_SEEK_THRESHOLD 10 /* segments */
|
| 825 |
|
|
#define ZFT_FAST_SEEK_MAX_TRIALS 10 /* times */
|
| 826 |
|
|
#define ZFT_FAST_SEEK_BACKUP 10 /* segments */
|
| 827 |
|
|
|
| 828 |
|
|
static int zftc_seek(unsigned int new_block_pos,
|
| 829 |
|
|
zft_position *pos, const zft_volinfo *volume, __u8 *buf)
|
| 830 |
|
|
{
|
| 831 |
|
|
unsigned int dest;
|
| 832 |
|
|
int limit;
|
| 833 |
|
|
int distance;
|
| 834 |
|
|
int result = 0;
|
| 835 |
|
|
int seg_dist;
|
| 836 |
|
|
int new_seg;
|
| 837 |
|
|
int old_seg = 0;
|
| 838 |
|
|
int fast_seek_trials = 0;
|
| 839 |
|
|
TRACE_FUN(ft_t_flow);
|
| 840 |
|
|
|
| 841 |
|
|
keep_module_locked = 1;
|
| 842 |
|
|
#if LINUX_VERSION_CODE >= KERNEL_VER(2,1,18)
|
| 843 |
|
|
MOD_INC_USE_COUNT; /* sets MOD_VISITED and MOD_USED_ONCE,
|
| 844 |
|
|
* locking is done with can_unload()
|
| 845 |
|
|
*/
|
| 846 |
|
|
#else
|
| 847 |
|
|
if (!MOD_IN_USE) {
|
| 848 |
|
|
MOD_INC_USE_COUNT;
|
| 849 |
|
|
}
|
| 850 |
|
|
#endif
|
| 851 |
|
|
if (new_block_pos == 0) {
|
| 852 |
|
|
pos->seg_pos = volume->start_seg;
|
| 853 |
|
|
pos->seg_byte_pos = 0;
|
| 854 |
|
|
pos->volume_pos = 0;
|
| 855 |
|
|
zftc_reset();
|
| 856 |
|
|
TRACE_EXIT 0;
|
| 857 |
|
|
}
|
| 858 |
|
|
dest = new_block_pos * (volume->blk_sz >> 10);
|
| 859 |
|
|
distance = dest - (pos->volume_pos >> 10);
|
| 860 |
|
|
while (distance != 0) {
|
| 861 |
|
|
seg_dist = compute_seg_pos(dest, pos, volume);
|
| 862 |
|
|
TRACE(ft_t_noise, "\n"
|
| 863 |
|
|
KERN_INFO "seg_dist: %d\n"
|
| 864 |
|
|
KERN_INFO "distance: %d\n"
|
| 865 |
|
|
KERN_INFO "dest : %d\n"
|
| 866 |
|
|
KERN_INFO "vpos : %d\n"
|
| 867 |
|
|
KERN_INFO "seg_pos : %d\n"
|
| 868 |
|
|
KERN_INFO "trials : %d",
|
| 869 |
|
|
seg_dist, distance, dest,
|
| 870 |
|
|
(unsigned int)(pos->volume_pos>>10), pos->seg_pos,
|
| 871 |
|
|
fast_seek_trials);
|
| 872 |
|
|
if (distance > 0) {
|
| 873 |
|
|
if (seg_dist < 0) {
|
| 874 |
|
|
TRACE(ft_t_bug, "BUG: distance %d > 0, "
|
| 875 |
|
|
"segment difference %d < 0",
|
| 876 |
|
|
distance, seg_dist);
|
| 877 |
|
|
result = -EIO;
|
| 878 |
|
|
break;
|
| 879 |
|
|
}
|
| 880 |
|
|
new_seg = pos->seg_pos + seg_dist;
|
| 881 |
|
|
if (new_seg > volume->end_seg) {
|
| 882 |
|
|
new_seg = volume->end_seg;
|
| 883 |
|
|
}
|
| 884 |
|
|
if (old_seg == new_seg || /* loop */
|
| 885 |
|
|
seg_dist <= ZFT_SLOW_SEEK_THRESHOLD ||
|
| 886 |
|
|
fast_seek_trials >= ZFT_FAST_SEEK_MAX_TRIALS) {
|
| 887 |
|
|
TRACE(ft_t_noise, "starting slow seek:\n"
|
| 888 |
|
|
KERN_INFO "fast seek failed too often: %s\n"
|
| 889 |
|
|
KERN_INFO "near target position : %s\n"
|
| 890 |
|
|
KERN_INFO "looping between two segs : %s",
|
| 891 |
|
|
(fast_seek_trials >=
|
| 892 |
|
|
ZFT_FAST_SEEK_MAX_TRIALS)
|
| 893 |
|
|
? "yes" : "no",
|
| 894 |
|
|
(seg_dist <= ZFT_SLOW_SEEK_THRESHOLD)
|
| 895 |
|
|
? "yes" : "no",
|
| 896 |
|
|
(old_seg == new_seg)
|
| 897 |
|
|
? "yes" : "no");
|
| 898 |
|
|
result = slow_seek_forward(dest, &cseg,
|
| 899 |
|
|
pos, volume, buf);
|
| 900 |
|
|
break;
|
| 901 |
|
|
}
|
| 902 |
|
|
old_seg = new_seg;
|
| 903 |
|
|
limit = volume->end_seg;
|
| 904 |
|
|
fast_seek_trials ++;
|
| 905 |
|
|
for (;;) {
|
| 906 |
|
|
result = search_valid_segment(new_seg, limit,
|
| 907 |
|
|
volume->size,
|
| 908 |
|
|
pos, &cseg,
|
| 909 |
|
|
volume, buf);
|
| 910 |
|
|
if (result == 0 || result == -EINTR) {
|
| 911 |
|
|
break;
|
| 912 |
|
|
}
|
| 913 |
|
|
if (new_seg == volume->start_seg) {
|
| 914 |
|
|
result = -EIO; /* set errror
|
| 915 |
|
|
* condition
|
| 916 |
|
|
*/
|
| 917 |
|
|
break;
|
| 918 |
|
|
}
|
| 919 |
|
|
limit = new_seg;
|
| 920 |
|
|
new_seg -= ZFT_FAST_SEEK_BACKUP;
|
| 921 |
|
|
if (new_seg < volume->start_seg) {
|
| 922 |
|
|
new_seg = volume->start_seg;
|
| 923 |
|
|
}
|
| 924 |
|
|
}
|
| 925 |
|
|
if (result < 0) {
|
| 926 |
|
|
TRACE(ft_t_warn,
|
| 927 |
|
|
"Couldn't find a readable segment");
|
| 928 |
|
|
break;
|
| 929 |
|
|
}
|
| 930 |
|
|
} else /* if (distance < 0) */ {
|
| 931 |
|
|
if (seg_dist > 0) {
|
| 932 |
|
|
TRACE(ft_t_bug, "BUG: distance %d < 0, "
|
| 933 |
|
|
"segment difference %d >0",
|
| 934 |
|
|
distance, seg_dist);
|
| 935 |
|
|
result = -EIO;
|
| 936 |
|
|
break;
|
| 937 |
|
|
}
|
| 938 |
|
|
new_seg = pos->seg_pos + seg_dist;
|
| 939 |
|
|
if (fast_seek_trials > 0 && seg_dist == 0) {
|
| 940 |
|
|
/* this avoids sticking to the same
|
| 941 |
|
|
* segment all the time. On the other hand:
|
| 942 |
|
|
* if we got here for the first time, and the
|
| 943 |
|
|
* deblock_buffer still contains a valid
|
| 944 |
|
|
* segment, then there is no need to skip to
|
| 945 |
|
|
* the previous segment if the desired position
|
| 946 |
|
|
* is inside this segment.
|
| 947 |
|
|
*/
|
| 948 |
|
|
new_seg --;
|
| 949 |
|
|
}
|
| 950 |
|
|
if (new_seg < volume->start_seg) {
|
| 951 |
|
|
new_seg = volume->start_seg;
|
| 952 |
|
|
}
|
| 953 |
|
|
limit = pos->seg_pos;
|
| 954 |
|
|
fast_seek_trials ++;
|
| 955 |
|
|
for (;;) {
|
| 956 |
|
|
result = search_valid_segment(new_seg, limit,
|
| 957 |
|
|
pos->volume_pos,
|
| 958 |
|
|
pos, &cseg,
|
| 959 |
|
|
volume, buf);
|
| 960 |
|
|
if (result == 0 || result == -EINTR) {
|
| 961 |
|
|
break;
|
| 962 |
|
|
}
|
| 963 |
|
|
if (new_seg == volume->start_seg) {
|
| 964 |
|
|
result = -EIO; /* set errror
|
| 965 |
|
|
* condition
|
| 966 |
|
|
*/
|
| 967 |
|
|
break;
|
| 968 |
|
|
}
|
| 969 |
|
|
limit = new_seg;
|
| 970 |
|
|
new_seg -= ZFT_FAST_SEEK_BACKUP;
|
| 971 |
|
|
if (new_seg < volume->start_seg) {
|
| 972 |
|
|
new_seg = volume->start_seg;
|
| 973 |
|
|
}
|
| 974 |
|
|
}
|
| 975 |
|
|
if (result < 0) {
|
| 976 |
|
|
TRACE(ft_t_warn,
|
| 977 |
|
|
"Couldn't find a readable segment");
|
| 978 |
|
|
break;
|
| 979 |
|
|
}
|
| 980 |
|
|
}
|
| 981 |
|
|
distance = dest - (pos->volume_pos >> 10);
|
| 982 |
|
|
}
|
| 983 |
|
|
TRACE_EXIT result;
|
| 984 |
|
|
}
|
| 985 |
|
|
|
| 986 |
|
|
|
| 987 |
|
|
/* advance inside the given segment at most to_do bytes.
|
| 988 |
|
|
* of kilobytes moved
|
| 989 |
|
|
*/
|
| 990 |
|
|
|
| 991 |
|
|
static int seek_in_segment(const unsigned int to_do,
|
| 992 |
|
|
cmpr_info *c_info,
|
| 993 |
|
|
const char *src_buf,
|
| 994 |
|
|
const int seg_sz,
|
| 995 |
|
|
const int seg_pos,
|
| 996 |
|
|
const zft_volinfo *volume)
|
| 997 |
|
|
{
|
| 998 |
|
|
int result = 0;
|
| 999 |
|
|
int blk_sz = volume->blk_sz >> 10;
|
| 1000 |
|
|
int remaining = to_do;
|
| 1001 |
|
|
TRACE_FUN(ft_t_flow);
|
| 1002 |
|
|
|
| 1003 |
|
|
if (c_info->offset == 0) {
|
| 1004 |
|
|
/* new segment just read
|
| 1005 |
|
|
*/
|
| 1006 |
|
|
TRACE_CATCH(get_cseg(c_info, src_buf, seg_sz, volume),);
|
| 1007 |
|
|
c_info->cmpr_pos += c_info->count;
|
| 1008 |
|
|
DUMP_CMPR_INFO(ft_t_noise, "", c_info);
|
| 1009 |
|
|
}
|
| 1010 |
|
|
/* loop and uncompress until user buffer full or
|
| 1011 |
|
|
* deblock-buffer empty
|
| 1012 |
|
|
*/
|
| 1013 |
|
|
TRACE(ft_t_noise, "compressed_sz: %d, compos : %d",
|
| 1014 |
|
|
c_info->cmpr_sz, c_info->cmpr_pos);
|
| 1015 |
|
|
while (c_info->spans == 0 && remaining > 0) {
|
| 1016 |
|
|
if (c_info->cmpr_pos != 0) { /* cmpr buf is not empty */
|
| 1017 |
|
|
result += blk_sz;
|
| 1018 |
|
|
remaining -= blk_sz;
|
| 1019 |
|
|
c_info->cmpr_pos = 0;
|
| 1020 |
|
|
}
|
| 1021 |
|
|
if (remaining > 0) {
|
| 1022 |
|
|
get_next_cluster(c_info, src_buf, seg_sz,
|
| 1023 |
|
|
volume->end_seg == seg_pos);
|
| 1024 |
|
|
if (c_info->count != 0) {
|
| 1025 |
|
|
c_info->cmpr_pos = c_info->count;
|
| 1026 |
|
|
c_info->offset += c_info->count;
|
| 1027 |
|
|
} else {
|
| 1028 |
|
|
break;
|
| 1029 |
|
|
}
|
| 1030 |
|
|
}
|
| 1031 |
|
|
/* Allow escape from this loop on signal!
|
| 1032 |
|
|
*/
|
| 1033 |
|
|
FT_SIGNAL_EXIT(_DONT_BLOCK);
|
| 1034 |
|
|
DUMP_CMPR_INFO(ft_t_noise, "", c_info);
|
| 1035 |
|
|
TRACE(ft_t_noise, "to_do: %d", remaining);
|
| 1036 |
|
|
}
|
| 1037 |
|
|
if (seg_sz - c_info->offset <= 18) {
|
| 1038 |
|
|
c_info->offset = seg_sz;
|
| 1039 |
|
|
}
|
| 1040 |
|
|
TRACE(ft_t_noise, "\n"
|
| 1041 |
|
|
KERN_INFO "segment size : %d\n"
|
| 1042 |
|
|
KERN_INFO "buf_pos_read : %d\n"
|
| 1043 |
|
|
KERN_INFO "remaining : %d",
|
| 1044 |
|
|
seg_sz, c_info->offset,
|
| 1045 |
|
|
seg_sz - c_info->offset);
|
| 1046 |
|
|
TRACE_EXIT result;
|
| 1047 |
|
|
}
|
| 1048 |
|
|
|
| 1049 |
|
|
static int slow_seek_forward_until_error(const unsigned int distance,
|
| 1050 |
|
|
cmpr_info *c_info,
|
| 1051 |
|
|
zft_position *pos,
|
| 1052 |
|
|
const zft_volinfo *volume,
|
| 1053 |
|
|
__u8 *buf)
|
| 1054 |
|
|
{
|
| 1055 |
|
|
unsigned int remaining = distance;
|
| 1056 |
|
|
int seg_sz;
|
| 1057 |
|
|
int seg_pos;
|
| 1058 |
|
|
int result;
|
| 1059 |
|
|
TRACE_FUN(ft_t_flow);
|
| 1060 |
|
|
|
| 1061 |
|
|
seg_pos = pos->seg_pos;
|
| 1062 |
|
|
do {
|
| 1063 |
|
|
TRACE_CATCH(seg_sz = zft_fetch_segment(seg_pos, buf,
|
| 1064 |
|
|
FT_RD_AHEAD),);
|
| 1065 |
|
|
/* now we have the contents of the actual segment in
|
| 1066 |
|
|
* the deblock buffer
|
| 1067 |
|
|
*/
|
| 1068 |
|
|
TRACE_CATCH(result = seek_in_segment(remaining, c_info, buf,
|
| 1069 |
|
|
seg_sz, seg_pos,volume),);
|
| 1070 |
|
|
remaining -= result;
|
| 1071 |
|
|
pos->volume_pos += result<<10;
|
| 1072 |
|
|
pos->seg_pos = seg_pos;
|
| 1073 |
|
|
pos->seg_byte_pos = c_info->offset;
|
| 1074 |
|
|
seg_pos ++;
|
| 1075 |
|
|
if (seg_pos <= volume->end_seg && c_info->offset == seg_sz) {
|
| 1076 |
|
|
pos->seg_pos ++;
|
| 1077 |
|
|
pos->seg_byte_pos = 0;
|
| 1078 |
|
|
c_info->offset = 0;
|
| 1079 |
|
|
}
|
| 1080 |
|
|
/* Allow escape from this loop on signal!
|
| 1081 |
|
|
*/
|
| 1082 |
|
|
FT_SIGNAL_EXIT(_DONT_BLOCK);
|
| 1083 |
|
|
TRACE(ft_t_noise, "\n"
|
| 1084 |
|
|
KERN_INFO "remaining: %d\n"
|
| 1085 |
|
|
KERN_INFO "seg_pos: %d\n"
|
| 1086 |
|
|
KERN_INFO "end_seg: %d\n"
|
| 1087 |
|
|
KERN_INFO "result: %d",
|
| 1088 |
|
|
remaining, seg_pos, volume->end_seg, result);
|
| 1089 |
|
|
} while (remaining > 0 && seg_pos <= volume->end_seg);
|
| 1090 |
|
|
TRACE_EXIT 0;
|
| 1091 |
|
|
}
|
| 1092 |
|
|
|
| 1093 |
|
|
/* return segment id of next segment containing valid data, -EIO otherwise
|
| 1094 |
|
|
*/
|
| 1095 |
|
|
static int search_valid_segment(unsigned int segment,
|
| 1096 |
|
|
const unsigned int end_seg,
|
| 1097 |
|
|
const unsigned int max_foffs,
|
| 1098 |
|
|
zft_position *pos,
|
| 1099 |
|
|
cmpr_info *c_info,
|
| 1100 |
|
|
const zft_volinfo *volume,
|
| 1101 |
|
|
__u8 *buf)
|
| 1102 |
|
|
{
|
| 1103 |
|
|
cmpr_info tmp_info;
|
| 1104 |
|
|
int seg_sz;
|
| 1105 |
|
|
TRACE_FUN(ft_t_flow);
|
| 1106 |
|
|
|
| 1107 |
|
|
memset(&tmp_info, 0, sizeof(cmpr_info));
|
| 1108 |
|
|
while (segment <= end_seg) {
|
| 1109 |
|
|
FT_SIGNAL_EXIT(_DONT_BLOCK);
|
| 1110 |
|
|
TRACE(ft_t_noise,
|
| 1111 |
|
|
"Searching readable segment between %d and %d",
|
| 1112 |
|
|
segment, end_seg);
|
| 1113 |
|
|
seg_sz = zft_fetch_segment(segment, buf, FT_RD_AHEAD);
|
| 1114 |
|
|
if ((seg_sz > 0) &&
|
| 1115 |
|
|
(get_cseg (&tmp_info, buf, seg_sz, volume) >= 0) &&
|
| 1116 |
|
|
(tmp_info.foffs != 0 || segment == volume->start_seg)) {
|
| 1117 |
|
|
if ((tmp_info.foffs>>10) > max_foffs) {
|
| 1118 |
|
|
TRACE_ABORT(-EIO, ft_t_noise, "\n"
|
| 1119 |
|
|
KERN_INFO "cseg.foff: %d\n"
|
| 1120 |
|
|
KERN_INFO "dest : %d",
|
| 1121 |
|
|
(int)(tmp_info.foffs >> 10),
|
| 1122 |
|
|
max_foffs);
|
| 1123 |
|
|
}
|
| 1124 |
|
|
DUMP_CMPR_INFO(ft_t_noise, "", &tmp_info);
|
| 1125 |
|
|
*c_info = tmp_info;
|
| 1126 |
|
|
pos->seg_pos = segment;
|
| 1127 |
|
|
pos->volume_pos = c_info->foffs;
|
| 1128 |
|
|
pos->seg_byte_pos = c_info->offset;
|
| 1129 |
|
|
TRACE(ft_t_noise, "found segment at %d", segment);
|
| 1130 |
|
|
TRACE_EXIT 0;
|
| 1131 |
|
|
}
|
| 1132 |
|
|
segment++;
|
| 1133 |
|
|
}
|
| 1134 |
|
|
TRACE_EXIT -EIO;
|
| 1135 |
|
|
}
|
| 1136 |
|
|
|
| 1137 |
|
|
static int slow_seek_forward(unsigned int dest,
|
| 1138 |
|
|
cmpr_info *c_info,
|
| 1139 |
|
|
zft_position *pos,
|
| 1140 |
|
|
const zft_volinfo *volume,
|
| 1141 |
|
|
__u8 *buf)
|
| 1142 |
|
|
{
|
| 1143 |
|
|
unsigned int distance;
|
| 1144 |
|
|
int result = 0;
|
| 1145 |
|
|
TRACE_FUN(ft_t_flow);
|
| 1146 |
|
|
|
| 1147 |
|
|
distance = dest - (pos->volume_pos >> 10);
|
| 1148 |
|
|
while ((distance > 0) &&
|
| 1149 |
|
|
(result = slow_seek_forward_until_error(distance,
|
| 1150 |
|
|
c_info,
|
| 1151 |
|
|
pos,
|
| 1152 |
|
|
volume,
|
| 1153 |
|
|
buf)) < 0) {
|
| 1154 |
|
|
if (result == -EINTR) {
|
| 1155 |
|
|
break;
|
| 1156 |
|
|
}
|
| 1157 |
|
|
TRACE(ft_t_noise, "seg_pos: %d", pos->seg_pos);
|
| 1158 |
|
|
/* the failing segment is either pos->seg_pos or
|
| 1159 |
|
|
* pos->seg_pos + 1. There is no need to further try
|
| 1160 |
|
|
* that segment, because ftape_read_segment() already
|
| 1161 |
|
|
* has tried very much to read it. So we start with
|
| 1162 |
|
|
* following segment, which is pos->seg_pos + 1
|
| 1163 |
|
|
*/
|
| 1164 |
|
|
if(search_valid_segment(pos->seg_pos+1, volume->end_seg, dest,
|
| 1165 |
|
|
pos, c_info,
|
| 1166 |
|
|
volume, buf) < 0) {
|
| 1167 |
|
|
TRACE(ft_t_noise, "search_valid_segment() failed");
|
| 1168 |
|
|
result = -EIO;
|
| 1169 |
|
|
break;
|
| 1170 |
|
|
}
|
| 1171 |
|
|
distance = dest - (pos->volume_pos >> 10);
|
| 1172 |
|
|
result = 0;
|
| 1173 |
|
|
TRACE(ft_t_noise, "segment: %d", pos->seg_pos);
|
| 1174 |
|
|
/* found valid segment, retry the seek */
|
| 1175 |
|
|
}
|
| 1176 |
|
|
TRACE_EXIT result;
|
| 1177 |
|
|
}
|
| 1178 |
|
|
|
| 1179 |
|
|
static int compute_seg_pos(const unsigned int dest,
|
| 1180 |
|
|
zft_position *pos,
|
| 1181 |
|
|
const zft_volinfo *volume)
|
| 1182 |
|
|
{
|
| 1183 |
|
|
int segment;
|
| 1184 |
|
|
int distance = dest - (pos->volume_pos >> 10);
|
| 1185 |
|
|
unsigned int raw_size;
|
| 1186 |
|
|
unsigned int virt_size;
|
| 1187 |
|
|
unsigned int factor;
|
| 1188 |
|
|
TRACE_FUN(ft_t_flow);
|
| 1189 |
|
|
|
| 1190 |
|
|
if (distance >= 0) {
|
| 1191 |
|
|
raw_size = volume->end_seg - pos->seg_pos + 1;
|
| 1192 |
|
|
virt_size = ((unsigned int)(volume->size>>10)
|
| 1193 |
|
|
- (unsigned int)(pos->volume_pos>>10)
|
| 1194 |
|
|
+ FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS - 1);
|
| 1195 |
|
|
virt_size /= FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS;
|
| 1196 |
|
|
if (virt_size == 0 || raw_size == 0) {
|
| 1197 |
|
|
TRACE_EXIT 0;
|
| 1198 |
|
|
}
|
| 1199 |
|
|
if (raw_size >= (1<<25)) {
|
| 1200 |
|
|
factor = raw_size/(virt_size>>7);
|
| 1201 |
|
|
} else {
|
| 1202 |
|
|
factor = (raw_size<<7)/virt_size;
|
| 1203 |
|
|
}
|
| 1204 |
|
|
segment = distance/(FT_SECTORS_PER_SEGMENT-FT_ECC_SECTORS);
|
| 1205 |
|
|
segment = (segment * factor)>>7;
|
| 1206 |
|
|
} else {
|
| 1207 |
|
|
raw_size = pos->seg_pos - volume->start_seg + 1;
|
| 1208 |
|
|
virt_size = ((unsigned int)(pos->volume_pos>>10)
|
| 1209 |
|
|
+ FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS - 1);
|
| 1210 |
|
|
virt_size /= FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS;
|
| 1211 |
|
|
if (virt_size == 0 || raw_size == 0) {
|
| 1212 |
|
|
TRACE_EXIT 0;
|
| 1213 |
|
|
}
|
| 1214 |
|
|
if (raw_size >= (1<<25)) {
|
| 1215 |
|
|
factor = raw_size/(virt_size>>7);
|
| 1216 |
|
|
} else {
|
| 1217 |
|
|
factor = (raw_size<<7)/virt_size;
|
| 1218 |
|
|
}
|
| 1219 |
|
|
segment = distance/(FT_SECTORS_PER_SEGMENT-FT_ECC_SECTORS);
|
| 1220 |
|
|
}
|
| 1221 |
|
|
TRACE(ft_t_noise, "factor: %d/%d", factor, 1<<7);
|
| 1222 |
|
|
TRACE_EXIT segment;
|
| 1223 |
|
|
}
|
| 1224 |
|
|
|
| 1225 |
|
|
static struct zft_cmpr_ops cmpr_ops = {
|
| 1226 |
|
|
zftc_write,
|
| 1227 |
|
|
zftc_read,
|
| 1228 |
|
|
zftc_seek,
|
| 1229 |
|
|
zftc_lock,
|
| 1230 |
|
|
zftc_reset,
|
| 1231 |
|
|
zftc_cleanup
|
| 1232 |
|
|
};
|
| 1233 |
|
|
|
| 1234 |
|
|
int zft_compressor_init(void)
|
| 1235 |
|
|
{
|
| 1236 |
|
|
TRACE_FUN(ft_t_flow);
|
| 1237 |
|
|
|
| 1238 |
|
|
#ifdef MODULE
|
| 1239 |
|
|
printk(KERN_INFO "zftape compressor v1.00a 970514 for " FTAPE_VERSION "\n");
|
| 1240 |
|
|
if (TRACE_LEVEL >= ft_t_info) {
|
| 1241 |
|
|
printk(
|
| 1242 |
|
|
KERN_INFO "(c) 1997 Claus-Justus Heine (claus@momo.math.rwth-aachen.de)\n"
|
| 1243 |
|
|
KERN_INFO "Compressor for zftape (lzrw3 algorithm)\n"
|
| 1244 |
|
|
KERN_INFO "Compiled for kernel version %s"
|
| 1245 |
|
|
#ifdef MODVERSIONS
|
| 1246 |
|
|
" with versioned symbols"
|
| 1247 |
|
|
#endif
|
| 1248 |
|
|
"\n", UTS_RELEASE);
|
| 1249 |
|
|
}
|
| 1250 |
|
|
#else /* !MODULE */
|
| 1251 |
|
|
/* print a short no-nonsense boot message */
|
| 1252 |
|
|
printk("zftape compressor v1.00a 970514 for Linux " UTS_RELEASE "\n");
|
| 1253 |
|
|
printk("For use with " FTAPE_VERSION "\n");
|
| 1254 |
|
|
#endif /* MODULE */
|
| 1255 |
|
|
TRACE(ft_t_info, "zft_compressor_init @ 0x%p", zft_compressor_init);
|
| 1256 |
|
|
TRACE(ft_t_info, "installing compressor for zftape ...");
|
| 1257 |
|
|
TRACE_CATCH(zft_cmpr_register(&cmpr_ops),);
|
| 1258 |
|
|
TRACE_EXIT 0;
|
| 1259 |
|
|
}
|
| 1260 |
|
|
|
| 1261 |
|
|
#ifdef MODULE
|
| 1262 |
|
|
|
| 1263 |
|
|
MODULE_AUTHOR(
|
| 1264 |
|
|
"(c) 1996, 1997 Claus-Justus Heine (claus@momo.math.rwth-aachen.de");
|
| 1265 |
|
|
MODULE_DESCRIPTION(
|
| 1266 |
|
|
"Compression routines for zftape. Uses the lzrw3 algorithm by Ross Williams");
|
| 1267 |
|
|
MODULE_LICENSE("GPL");
|
| 1268 |
|
|
|
| 1269 |
|
|
#if LINUX_VERSION_CODE >= KERNEL_VER(2,1,18)
|
| 1270 |
|
|
static int can_unload(void)
|
| 1271 |
|
|
{
|
| 1272 |
|
|
return keep_module_locked ? -EBUSY : 0;
|
| 1273 |
|
|
}
|
| 1274 |
|
|
#endif
|
| 1275 |
|
|
|
| 1276 |
|
|
/* Called by modules package when installing the driver
|
| 1277 |
|
|
*/
|
| 1278 |
|
|
int init_module(void)
|
| 1279 |
|
|
{
|
| 1280 |
|
|
int result;
|
| 1281 |
|
|
|
| 1282 |
|
|
#if LINUX_VERSION_CODE < KERNEL_VER(2,1,18)
|
| 1283 |
|
|
register_symtab(0); /* remove global ftape symbols */
|
| 1284 |
|
|
#else
|
| 1285 |
|
|
if (!mod_member_present(&__this_module, can_unload))
|
| 1286 |
|
|
return -EBUSY;
|
| 1287 |
|
|
__this_module.can_unload = can_unload;
|
| 1288 |
|
|
EXPORT_NO_SYMBOLS;
|
| 1289 |
|
|
#endif
|
| 1290 |
|
|
result = zft_compressor_init();
|
| 1291 |
|
|
keep_module_locked = 0;
|
| 1292 |
|
|
return result;
|
| 1293 |
|
|
}
|
| 1294 |
|
|
|
| 1295 |
|
|
/* Called by modules package when removing the driver
|
| 1296 |
|
|
*/
|
| 1297 |
|
|
void cleanup_module(void)
|
| 1298 |
|
|
{
|
| 1299 |
|
|
TRACE_FUN(ft_t_flow);
|
| 1300 |
|
|
|
| 1301 |
|
|
if (zft_cmpr_unregister() != &cmpr_ops) {
|
| 1302 |
|
|
TRACE(ft_t_info, "failed");
|
| 1303 |
|
|
} else {
|
| 1304 |
|
|
TRACE(ft_t_info, "successful");
|
| 1305 |
|
|
}
|
| 1306 |
|
|
zftc_cleanup();
|
| 1307 |
|
|
printk(KERN_INFO "zft-compressor successfully unloaded.\n");
|
| 1308 |
|
|
TRACE_EXIT;
|
| 1309 |
|
|
}
|
| 1310 |
|
|
#endif /* MODULE */
|
