diff options
Diffstat (limited to 'drivers/char/ftape/zftape/zftape-rw.h')
-rw-r--r-- | drivers/char/ftape/zftape/zftape-rw.h | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/drivers/char/ftape/zftape/zftape-rw.h b/drivers/char/ftape/zftape/zftape-rw.h new file mode 100644 index 00000000000..14c07f08657 --- /dev/null +++ b/drivers/char/ftape/zftape/zftape-rw.h @@ -0,0 +1,102 @@ +#ifndef _ZFTAPE_RW_H +#define _ZFTAPE_RW_H + +/* + * Copyright (C) 1996, 1997 Claus-Justus Heine. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; see the file COPYING. If not, write to + the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. + + * + * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-rw.h,v $ + * $Revision: 1.2 $ + * $Date: 1997/10/05 19:19:09 $ + * + * This file contains the definitions for the read and write + * functions for the QIC-117 floppy-tape driver for Linux. + * + */ + +#include <linux/config.h> /* for CONFIG_ZFT_DFLT_BLK_SZ */ +#include "../zftape/zftape-buffers.h" + +#define SEGMENTS_PER_TAPE (ft_segments_per_track * ft_tracks_per_tape) + +/* QIC-113 Rev. G says that `a maximum of 63488 raw bytes may be + * compressed into a single frame'. + * Maybe we should stick to 32kb to make it more `beautiful' + */ +#define ZFT_MAX_BLK_SZ (62*1024) /* bytes */ +#if !defined(CONFIG_ZFT_DFLT_BLK_SZ) +# define CONFIG_ZFT_DFLT_BLK_SZ (10*1024) /* bytes, default of gnu tar */ +#elif CONFIG_ZFT_DFLT_BLK_SZ == 0 +# undef CONFIG_ZFT_DFLT_BLK_SZ +# define CONFIG_ZFT_DFLT_BLK_SZ 1 +#elif (CONFIG_ZFT_DFLT_BLK_SZ % 1024) != 0 +# error CONFIG_ZFT_DFLT_BLK_SZ must be 1 or a multiple of 1024 +#endif +/* The *optional* compression routines need some overhead per tape + * block for their purposes. Instead of asking the actual compression + * implementation how much it needs, we restrict this overhead to be + * maximal of ZFT_CMPT_OVERHEAD size. We need this for EOT + * conditions. The tape is assumed to be logical at EOT when the + * distance from the physical EOT is less than + * one tape block + ZFT_CMPR_OVERHEAD + */ +#define ZFT_CMPR_OVERHEAD 16 /* bytes */ + +typedef enum +{ + zft_idle = 0, + zft_reading, + zft_writing, +} zft_status_enum; + +typedef struct /* all values measured in bytes */ +{ + int seg_pos; /* segment currently positioned at */ + int seg_byte_pos; /* offset in current segment */ + __s64 tape_pos; /* real offset from BOT */ + __s64 volume_pos; /* pos. in uncompressed data stream in + * current volume + */ +} zft_position; + +extern zft_position zft_pos; +extern __u8 *zft_deblock_buf; +extern __u8 *zft_hseg_buf; +extern int zft_deblock_segment; +extern zft_status_enum zft_io_state; +extern int zft_header_changed; +extern int zft_qic113; /* conform to old specs. and old zftape */ +extern int zft_use_compression; +extern unsigned int zft_blk_sz; +extern __s64 zft_capacity; +extern unsigned int zft_written_segments; +extern int zft_label_changed; + +/* zftape-rw.c exported functions + */ +extern unsigned int zft_get_seg_sz(unsigned int segment); +extern void zft_set_flags(unsigned int minor_unit); +extern int zft_calc_seg_byte_coord(int *seg_byte_pos, __s64 tape_pos); +extern __s64 zft_calc_tape_pos(int segment); +extern __s64 zft_get_capacity(void); +extern void zft_update_label(__u8 *buffer); +extern int zft_erase(void); +extern int zft_verify_write_segments(unsigned int segment, + __u8 *data, size_t size, __u8 *buffer); +extern unsigned int zft_get_time(void); +#endif /* _ZFTAPE_RW_H */ + |