diff options
Diffstat (limited to 'drivers/char/ftape/zftape/zftape-vtbl.h')
| -rw-r--r-- | drivers/char/ftape/zftape/zftape-vtbl.h | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/char/ftape/zftape/zftape-vtbl.h b/drivers/char/ftape/zftape/zftape-vtbl.h new file mode 100644 index 000000000000..f31d196d1759 --- /dev/null +++ b/drivers/char/ftape/zftape/zftape-vtbl.h @@ -0,0 +1,227 @@ +#ifndef _ZFTAPE_VTBL_H +#define _ZFTAPE_VTBL_H + +/* + * Copyright (c) 1995-1997 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-vtbl.h,v $ + * $Revision: 1.3 $ + * $Date: 1997/10/28 14:30:09 $ + * + * This file defines a volume table as defined in the QIC-80 + * development standards. + */ + +#include <linux/list.h> + +#include "../lowlevel/ftape-tracing.h" + +#include "../zftape/zftape-eof.h" +#include "../zftape/zftape-ctl.h" +#include "../zftape/zftape-rw.h" + +#define VTBL_SIZE 128 /* bytes */ + +/* The following are offsets in the vtbl. */ +#define VTBL_SIG 0 +#define VTBL_START 4 +#define VTBL_END 6 +#define VTBL_DESC 8 +#define VTBL_DATE 52 +#define VTBL_FLAGS 56 +#define VTBL_FL_VENDOR_SPECIFIC (1<<0) +#define VTBL_FL_MUTLI_CARTRIDGE (1<<1) +#define VTBL_FL_NOT_VERIFIED (1<<2) +#define VTBL_FL_REDIR_INHIBIT (1<<3) +#define VTBL_FL_SEG_SPANNING (1<<4) +#define VTBL_FL_DIRECTORY_LAST (1<<5) +#define VTBL_FL_RESERVED_6 (1<<6) +#define VTBL_FL_RESERVED_7 (1<<7) +#define VTBL_M_NO 57 +#define VTBL_EXT 58 +#define EXT_ZFTAPE_SIG 0 +#define EXT_ZFTAPE_BLKSZ 10 +#define EXT_ZFTAPE_CMAP 12 +#define EXT_ZFTAPE_QIC113 13 +#define VTBL_PWD 84 +#define VTBL_DIR_SIZE 92 +#define VTBL_DATA_SIZE 96 +#define VTBL_OS_VERSION 104 +#define VTBL_SRC_DRIVE 106 +#define VTBL_DEV 122 +#define VTBL_RESERVED_1 123 +#define VTBL_CMPR 124 +#define VTBL_CMPR_UNREG 0x3f +#define VTBL_CMPR_USED 0x80 +#define VTBL_FMT 125 +#define VTBL_RESERVED_2 126 +#define VTBL_RESERVED_3 127 +/* compatibility with pre revision K */ +#define VTBL_K_CMPR 120 + +/* the next is used by QIC-3020 tapes with format code 6 (>2^16 + * segments) It is specified in QIC-113, Rev. G, Section 5 (SCSI + * volume table). The difference is simply, that we only store the + * number of segments used, not the starting segment. + */ +#define VTBL_SCSI_SEGS 4 /* is a 4 byte value */ + +/* one vtbl is 128 bytes, that results in a maximum number of + * 29*1024/128 = 232 volumes. + */ +#define ZFT_MAX_VOLUMES (FT_SEGMENT_SIZE/VTBL_SIZE) +#define VTBL_ID "VTBL" +#define VTBL_IDS { VTBL_ID, "XTBL", "UTID", "EXVT" } /* other valid ids */ +#define ZFT_VOL_NAME "zftape volume" /* volume label used by me */ +#define ZFTAPE_SIG "LINUX ZFT" + +/* global variables + */ +typedef struct zft_internal_vtbl +{ + struct list_head node; + int count; + unsigned int start_seg; /* 32 bits are enough for now */ + unsigned int end_seg; /* 32 bits are enough for now */ + __s64 size; /* uncompressed size */ + unsigned int blk_sz; /* block size for this volume */ + unsigned int zft_volume :1; /* zftape created this volume */ + unsigned int use_compression:1; /* compressed volume */ + unsigned int qic113 :1; /* layout of compressed block + * info and vtbl conforms to + * QIC-113, Rev. G + */ + unsigned int new_volume :1; /* it was created by us, this + * run. this allows the + * fields that aren't really + * used by zftape to be filled + * in by some user level + * program. + */ + unsigned int open :1; /* just in progress of being + * written + */ +} zft_volinfo; + +extern struct list_head zft_vtbl; +#define zft_head_vtbl list_entry(zft_vtbl.next, zft_volinfo, node) +#define zft_eom_vtbl list_entry(zft_vtbl.prev, zft_volinfo, node) +#define zft_last_vtbl list_entry(zft_eom_vtbl->node.prev, zft_volinfo, node) +#define zft_first_vtbl list_entry(zft_head_vtbl->node.next, zft_volinfo, node) +#define zft_vtbl_empty (zft_eom_vtbl->node.prev == &zft_head_vtbl->node) + +#define DUMP_VOLINFO(level, desc, info) \ +{ \ + char tmp[21]; \ + strlcpy(tmp, desc, sizeof(tmp)); \ + TRACE(level, "Volume %d:\n" \ + KERN_INFO "description : %s\n" \ + KERN_INFO "first segment: %d\n" \ + KERN_INFO "last segment: %d\n" \ + KERN_INFO "size : " LL_X "\n" \ + KERN_INFO "block size : %d\n" \ + KERN_INFO "compression : %d\n" \ + KERN_INFO "zftape volume: %d\n" \ + KERN_INFO "QIC-113 conf.: %d", \ + (info)->count, tmp, (info)->start_seg, (info)->end_seg, \ + LL((info)->size), (info)->blk_sz, \ + (info)->use_compression != 0, (info)->zft_volume != 0, \ + (info)->qic113 != 0); \ +} + +extern int zft_qic_mode; +extern int zft_old_ftape; +extern int zft_volume_table_changed; + +/* exported functions */ +extern void zft_init_vtbl (void); +extern void zft_free_vtbl (void); +extern int zft_extract_volume_headers(__u8 *buffer); +extern int zft_update_volume_table (unsigned int segment); +extern int zft_open_volume (zft_position *pos, + int blk_sz, int use_compression); +extern int zft_close_volume (zft_position *pos); +extern const zft_volinfo *zft_find_volume(unsigned int seg_pos); +extern int zft_skip_volumes (int count, zft_position *pos); +extern __s64 zft_get_eom_pos (void); +extern void zft_skip_to_eom (zft_position *pos); +extern int zft_fake_volume_headers (eof_mark_union *eof_map, + int num_failed_sectors); +extern int zft_weof (unsigned int count, zft_position *pos); +extern void zft_move_past_eof (zft_position *pos); + +static inline int zft_tape_at_eod (const zft_position *pos); +static inline int zft_tape_at_lbot (const zft_position *pos); +static inline void zft_position_before_eof (zft_position *pos, + const zft_volinfo *volume); +static inline __s64 zft_check_for_eof(const zft_volinfo *vtbl, + const zft_position *pos); + +/* this function decrements the zft_seg_pos counter if we are right + * at the beginning of a segment. This is to handle fsfm/bsfm -- we + * need to position before the eof mark. NOTE: zft_tape_pos is not + * changed + */ +static inline void zft_position_before_eof(zft_position *pos, + const zft_volinfo *volume) +{ + TRACE_FUN(ft_t_flow); + + if (pos->seg_pos == volume->end_seg + 1 && pos->seg_byte_pos == 0) { + pos->seg_pos --; + pos->seg_byte_pos = zft_get_seg_sz(pos->seg_pos); + } + TRACE_EXIT; +} + +/* Mmmh. Is the position at the end of the last volume, that is right + * before the last EOF mark also logical an EOD condition? + */ +static inline int zft_tape_at_eod(const zft_position *pos) +{ + TRACE_FUN(ft_t_any); + + if (zft_qic_mode) { + TRACE_EXIT (pos->seg_pos >= zft_eom_vtbl->start_seg || + zft_last_vtbl->open); + } else { + TRACE_EXIT pos->seg_pos > ft_last_data_segment; + } +} + +static inline int zft_tape_at_lbot(const zft_position *pos) +{ + if (zft_qic_mode) { + return (pos->seg_pos <= zft_first_vtbl->start_seg && + pos->volume_pos == 0); + } else { + return (pos->seg_pos <= ft_first_data_segment && + pos->volume_pos == 0); + } +} + +/* This one checks for EOF. return remaing space (may be negative) + */ +static inline __s64 zft_check_for_eof(const zft_volinfo *vtbl, + const zft_position *pos) +{ + return (__s64)(vtbl->size - pos->volume_pos); +} + +#endif /* _ZFTAPE_VTBL_H */ |