linux-stable-rt/drivers/char/ftape/zftape/zftape-vtbl.h

228 lines
7.5 KiB
C

#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 */