1 #ifndef _ZFTAPE_RW_H 2 #define _ZFTAPE_RW_H 3 4 /* 5 * Copyright (C) 1996, 1997 Claus-Justus Heine. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2, or (at your option) 10 any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; see the file COPYING. If not, write to 19 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 20 21 * 22 * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-rw.h,v $ 23 * $Revision: 1.2 $ 24 * $Date: 1997/10/05 19:19:09 $ 25 * 26 * This file contains the definitions for the read and write 27 * functions for the QIC-117 floppy-tape driver for Linux. 28 * 29 */ 30 31 #include <linux/config.h> /* for CONFIG_ZFT_DFLT_BLK_SZ */ 32 #include "../zftape/zftape-buffers.h" 33 34 #define SEGMENTS_PER_TAPE (ft_segments_per_track * ft_tracks_per_tape) 35 36 /* QIC-113 Rev. G says that `a maximum of 63488 raw bytes may be 37 * compressed into a single frame'. 38 * Maybe we should stick to 32kb to make it more `beautiful' 39 */ 40 #define ZFT_MAX_BLK_SZ (62*1024) /* bytes */ 41 #if !defined(CONFIG_ZFT_DFLT_BLK_SZ) 42 # define CONFIG_ZFT_DFLT_BLK_SZ (10*1024) /* bytes, default of gnu tar */ 43 #elif CONFIG_ZFT_DFLT_BLK_SZ == 0 44 # undef CONFIG_ZFT_DFLT_BLK_SZ 45 # define CONFIG_ZFT_DFLT_BLK_SZ 1 46 #elif (CONFIG_ZFT_DFLT_BLK_SZ % 1024) != 0 47 # error CONFIG_ZFT_DFLT_BLK_SZ must be 1 or a multiple of 1024 48 #endif 49 /* The *optional* compression routines need some overhead per tape 50 * block for their purposes. Instead of asking the actual compression 51 * implementation how much it needs, we restrict this overhead to be 52 * maximal of ZFT_CMPT_OVERHEAD size. We need this for EOT 53 * conditions. The tape is assumed to be logical at EOT when the 54 * distance from the physical EOT is less than 55 * one tape block + ZFT_CMPR_OVERHEAD 56 */ 57 #define ZFT_CMPR_OVERHEAD 16 /* bytes */ 58 59 typedef enum 60 { 61 zft_idle = 0, 62 zft_reading, 63 zft_writing, 64 } zft_status_enum; 65 66 typedef struct /* all values measured in bytes */ 67 { 68 int seg_pos; /* segment currently positioned at */ 69 int seg_byte_pos; /* offset in current segment */ 70 __s64 tape_pos; /* real offset from BOT */ 71 __s64 volume_pos; /* pos. in uncompressed data stream in 72 * current volume 73 */ 74 } zft_position; 75 76 extern zft_position zft_pos; 77 extern __u8 *zft_deblock_buf; 78 extern __u8 *zft_hseg_buf; 79 extern int zft_deblock_segment; 80 extern zft_status_enum zft_io_state; 81 extern int zft_header_changed; 82 extern int zft_bad_sector_map_changed; 83 extern int zft_qic113; /* conform to old specs. and old zftape */ 84 extern int zft_use_compression; 85 extern unsigned int zft_blk_sz; 86 extern __s64 zft_capacity; 87 extern unsigned int zft_written_segments; 88 extern int zft_label_changed; 89 90 /* zftape-rw.c exported functions 91 */ 92 extern unsigned int zft_get_seg_sz(unsigned int segment); 93 extern void zft_set_flags(unsigned int minor_unit); 94 extern int zft_calc_seg_byte_coord(int *seg_byte_pos, __s64 tape_pos); 95 extern __s64 zft_calc_tape_pos(int segment); 96 extern __s64 zft_get_capacity(void); 97 extern void zft_update_label(__u8 *buffer); 98 extern int zft_erase(void); 99 extern int zft_verify_write_segments(unsigned int segment, 100 __u8 *data, size_t size, __u8 *buffer); 101 extern unsigned int zft_get_time(void); 102 #endif /* _ZFTAPE_RW_H */ 103 104