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linux/drivers/char/ftape/zftape/zftape-vtbl.c

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/*
* 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.c,v $
* $Revision: 1.7.6.1 $
* $Date: 1997/11/24 13:48:31 $
*
* This file defines a volume table as defined in various QIC
* standards.
*
* This is a minimal implementation, just allowing ordinary DOS
* :( prgrams to identify the cartridge as used.
*/
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/zftape.h>
#include "../zftape/zftape-init.h"
#include "../zftape/zftape-eof.h"
#include "../zftape/zftape-ctl.h"
#include "../zftape/zftape-write.h"
#include "../zftape/zftape-read.h"
#include "../zftape/zftape-rw.h"
#include "../zftape/zftape-vtbl.h"
#define ZFT_CMAP_HACK /* leave this defined to hide the compression map */
/*
* global variables
*/
int zft_qic_mode = 1; /* use the vtbl */
int zft_old_ftape; /* prevents old ftaped tapes to be overwritten */
int zft_volume_table_changed; /* for write_header_segments() */
/*
* private variables (only exported for inline functions)
*/
LIST_HEAD(zft_vtbl);
/* We could also allocate these dynamically when extracting the volume table
* sizeof(zft_volinfo) is about 32 or something close to that
*/
static zft_volinfo tape_vtbl;
static zft_volinfo eot_vtbl;
static zft_volinfo *cur_vtbl;
static inline void zft_new_vtbl_entry(void)
{
struct list_head *tmp = &zft_last_vtbl->node;
zft_volinfo *new = zft_kmalloc(sizeof(zft_volinfo));
list_add(&new->node, tmp);
new->count = zft_eom_vtbl->count ++;
}
void zft_free_vtbl(void)
{
for (;;) {
struct list_head *tmp = zft_vtbl.prev;
zft_volinfo *vtbl;
if (tmp == &zft_vtbl)
break;
list_del(tmp);
vtbl = list_entry(tmp, zft_volinfo, node);
zft_kfree(vtbl, sizeof(zft_volinfo));
}
INIT_LIST_HEAD(&zft_vtbl);
cur_vtbl = NULL;
}
/* initialize vtbl, called by ftape_new_cartridge()
*/
void zft_init_vtbl(void)
{
zft_volinfo *new;
zft_free_vtbl();
/* Create the two dummy vtbl entries
*/
new = zft_kmalloc(sizeof(zft_volinfo));
list_add(&new->node, &zft_vtbl);
new = zft_kmalloc(sizeof(zft_volinfo));
list_add(&new->node, &zft_vtbl);
zft_head_vtbl->end_seg = ft_first_data_segment;
zft_head_vtbl->blk_sz = zft_blk_sz;
zft_head_vtbl->count = -1;
zft_eom_vtbl->start_seg = ft_first_data_segment + 1;
zft_eom_vtbl->end_seg = ft_last_data_segment + 1;
zft_eom_vtbl->blk_sz = zft_blk_sz;
zft_eom_vtbl->count = 0;
/* Reset the pointer for zft_find_volume()
*/
cur_vtbl = zft_eom_vtbl;
/* initialize the dummy vtbl entries for zft_qic_mode == 0
*/
eot_vtbl.start_seg = ft_last_data_segment + 1;
eot_vtbl.end_seg = ft_last_data_segment + 1;
eot_vtbl.blk_sz = zft_blk_sz;
eot_vtbl.count = -1;
tape_vtbl.start_seg = ft_first_data_segment;
tape_vtbl.end_seg = ft_last_data_segment;
tape_vtbl.blk_sz = zft_blk_sz;
tape_vtbl.size = zft_capacity;
tape_vtbl.count = 0;
}
/* check for a valid VTBL signature.
*/
static int vtbl_signature_valid(__u8 signature[4])
{
const char *vtbl_ids[] = VTBL_IDS; /* valid signatures */
int j;
for (j = 0;
(j < NR_ITEMS(vtbl_ids)) && (memcmp(signature, vtbl_ids[j], 4) != 0);
j++);
return j < NR_ITEMS(vtbl_ids);
}
/* We used to store the block-size of the volume in the volume-label,
* using the keyword "blocksize". The blocksize written to the
* volume-label is in bytes.
*
* We use this now only for compatibility with old zftape version. We
* store the blocksize directly as binary number in the vendor
* extension part of the volume entry.
*/
static int check_volume_label(const char *label, int *blk_sz)
{
int valid_format;
char *blocksize;
TRACE_FUN(ft_t_flow);
TRACE(ft_t_noise, "called with \"%s\" / \"%s\"", label, ZFT_VOL_NAME);
if (strncmp(label, ZFT_VOL_NAME, strlen(ZFT_VOL_NAME)) != 0) {
*blk_sz = 1; /* smallest block size that we allow */
valid_format = 0;
} else {
TRACE(ft_t_noise, "got old style zftape vtbl entry");
/* get the default blocksize */
/* use the kernel strstr() */
blocksize= strstr(label, " blocksize ");
if (blocksize) {
blocksize += strlen(" blocksize ");
for(*blk_sz= 0;
*blocksize >= '0' && *blocksize <= '9';
blocksize++) {
*blk_sz *= 10;
*blk_sz += *blocksize - '0';
}
if (*blk_sz > ZFT_MAX_BLK_SZ) {
*blk_sz= 1;
valid_format= 0;
} else {
valid_format = 1;
}
} else {
*blk_sz= 1;
valid_format= 0;
}
}
TRACE_EXIT valid_format;
}
/* check for a zftape volume
*/
static int check_volume(__u8 *entry, zft_volinfo *volume)
{
TRACE_FUN(ft_t_flow);
if(strncmp(&entry[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG,
strlen(ZFTAPE_SIG)) == 0) {
TRACE(ft_t_noise, "got new style zftape vtbl entry");
volume->blk_sz = GET2(entry, VTBL_EXT+EXT_ZFTAPE_BLKSZ);
volume->qic113 = entry[VTBL_EXT+EXT_ZFTAPE_QIC113];
TRACE_EXIT 1;
} else {
TRACE_EXIT check_volume_label(&entry[VTBL_DESC], &volume->blk_sz);
}
}
/* create zftape specific vtbl entry, the volume bounds are inserted
* in the calling function, zft_create_volume_headers()
*/
static void create_zft_volume(__u8 *entry, zft_volinfo *vtbl)
{
TRACE_FUN(ft_t_flow);
memset(entry, 0, VTBL_SIZE);
memcpy(&entry[VTBL_SIG], VTBL_ID, 4);
sprintf(&entry[VTBL_DESC], ZFT_VOL_NAME" %03d", vtbl->count);
entry[VTBL_FLAGS] = (VTBL_FL_NOT_VERIFIED | VTBL_FL_SEG_SPANNING);
entry[VTBL_M_NO] = 1; /* multi_cartridge_count */
strcpy(&entry[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG);
PUT2(entry, VTBL_EXT+EXT_ZFTAPE_BLKSZ, vtbl->blk_sz);
if (zft_qic113) {
PUT8(entry, VTBL_DATA_SIZE, vtbl->size);
entry[VTBL_CMPR] = VTBL_CMPR_UNREG;
if (vtbl->use_compression) { /* use compression: */
entry[VTBL_CMPR] |= VTBL_CMPR_USED;
}
entry[VTBL_EXT+EXT_ZFTAPE_QIC113] = 1;
} else {
PUT4(entry, VTBL_DATA_SIZE, vtbl->size);
entry[VTBL_K_CMPR] = VTBL_CMPR_UNREG;
if (vtbl->use_compression) { /* use compression: */
entry[VTBL_K_CMPR] |= VTBL_CMPR_USED;
}
}
if (ft_format_code == fmt_big) {
/* SCSI like vtbl, store the number of used
* segments as 4 byte value
*/
PUT4(entry, VTBL_SCSI_SEGS, vtbl->end_seg-vtbl->start_seg + 1);
} else {
/* normal, QIC-80MC like vtbl
*/
PUT2(entry, VTBL_START, vtbl->start_seg);
PUT2(entry, VTBL_END, vtbl->end_seg);
}
TRACE_EXIT;
}
/* this one creates the volume headers for each volume. It is assumed
* that buffer already contains the old volume-table, so that vtbl
* entries without the zft_volume flag set can savely be ignored.
*/
static void zft_create_volume_headers(__u8 *buffer)
{
__u8 *entry;
struct list_head *tmp;
zft_volinfo *vtbl;
TRACE_FUN(ft_t_flow);
#ifdef ZFT_CMAP_HACK
if((strncmp(&buffer[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG,
strlen(ZFTAPE_SIG)) == 0) &&
buffer[VTBL_EXT+EXT_ZFTAPE_CMAP] != 0) {
TRACE(ft_t_noise, "deleting cmap volume");
memmove(buffer, buffer + VTBL_SIZE,
FT_SEGMENT_SIZE - VTBL_SIZE);
}
#endif
entry = buffer;
for (tmp = zft_head_vtbl->node.next;
tmp != &zft_eom_vtbl->node;
tmp = tmp->next) {
vtbl = list_entry(tmp, zft_volinfo, node);
/* we now fill in the values only for newly created volumes.
*/
if (vtbl->new_volume) {
create_zft_volume(entry, vtbl);
vtbl->new_volume = 0; /* clear the flag */
}
DUMP_VOLINFO(ft_t_noise, &entry[VTBL_DESC], vtbl);
entry += VTBL_SIZE;
}
memset(entry, 0, FT_SEGMENT_SIZE - zft_eom_vtbl->count * VTBL_SIZE);
TRACE_EXIT;
}
/* write volume table to tape. Calls zft_create_volume_headers()
*/
int zft_update_volume_table(unsigned int segment)
{
int result = 0;
__u8 *verify_buf = NULL;
TRACE_FUN(ft_t_flow);
TRACE_CATCH(result = ftape_read_segment(ft_first_data_segment,
zft_deblock_buf,
FT_RD_SINGLE),);
zft_create_volume_headers(zft_deblock_buf);
TRACE(ft_t_noise, "writing volume table segment %d", segment);
if (zft_vmalloc_once(&verify_buf, FT_SEGMENT_SIZE) == 0) {
TRACE_CATCH(zft_verify_write_segments(segment,
zft_deblock_buf, result,
verify_buf),
zft_vfree(&verify_buf, FT_SEGMENT_SIZE));
zft_vfree(&verify_buf, FT_SEGMENT_SIZE);
} else {
TRACE_CATCH(ftape_write_segment(segment, zft_deblock_buf,
FT_WR_SINGLE),);
}
TRACE_EXIT 0;
}
/* non zftape volumes are handled in raw mode. Thus we need to
* calculate the raw amount of data contained in those segments.
*/
static void extract_alien_volume(__u8 *entry, zft_volinfo *vtbl)
{
TRACE_FUN(ft_t_flow);
vtbl->size = (zft_calc_tape_pos(zft_last_vtbl->end_seg+1) -
zft_calc_tape_pos(zft_last_vtbl->start_seg));
vtbl->use_compression = 0;
vtbl->qic113 = zft_qic113;
if (vtbl->qic113) {
TRACE(ft_t_noise,
"Fake alien volume's size from " LL_X " to " LL_X,
LL(GET8(entry, VTBL_DATA_SIZE)), LL(vtbl->size));
} else {
TRACE(ft_t_noise,
"Fake alien volume's size from %d to " LL_X,
(int)GET4(entry, VTBL_DATA_SIZE), LL(vtbl->size));
}
TRACE_EXIT;
}
/* extract an zftape specific volume
*/
static void extract_zft_volume(__u8 *entry, zft_volinfo *vtbl)
{
TRACE_FUN(ft_t_flow);
if (vtbl->qic113) {
vtbl->size = GET8(entry, VTBL_DATA_SIZE);
vtbl->use_compression =
(entry[VTBL_CMPR] & VTBL_CMPR_USED) != 0;
} else {
vtbl->size = GET4(entry, VTBL_DATA_SIZE);
if (entry[VTBL_K_CMPR] & VTBL_CMPR_UNREG) {
vtbl->use_compression =
(entry[VTBL_K_CMPR] & VTBL_CMPR_USED) != 0;
} else if (entry[VTBL_CMPR] & VTBL_CMPR_UNREG) {
vtbl->use_compression =
(entry[VTBL_CMPR] & VTBL_CMPR_USED) != 0;
} else {
TRACE(ft_t_warn, "Geeh! There is something wrong:\n"
KERN_INFO "QIC compression (Rev = K): %x\n"
KERN_INFO "QIC compression (Rev > K): %x",
entry[VTBL_K_CMPR], entry[VTBL_CMPR]);
}
}
TRACE_EXIT;
}
/* extract the volume table from buffer. "buffer" must already contain
* the vtbl-segment
*/
int zft_extract_volume_headers(__u8 *buffer)
{
__u8 *entry;
TRACE_FUN(ft_t_flow);
zft_init_vtbl();
entry = buffer;
#ifdef ZFT_CMAP_HACK
if ((strncmp(&entry[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG,
strlen(ZFTAPE_SIG)) == 0) &&
entry[VTBL_EXT+EXT_ZFTAPE_CMAP] != 0) {
TRACE(ft_t_noise, "ignoring cmap volume");
entry += VTBL_SIZE;
}
#endif
/* the end of the vtbl is indicated by an invalid signature
*/
while (vtbl_signature_valid(&entry[VTBL_SIG]) &&
(entry - buffer) < FT_SEGMENT_SIZE) {
zft_new_vtbl_entry();
if (ft_format_code == fmt_big) {
/* SCSI like vtbl, stores only the number of
* segments used
*/
unsigned int num_segments= GET4(entry, VTBL_SCSI_SEGS);
zft_last_vtbl->start_seg = zft_eom_vtbl->start_seg;
zft_last_vtbl->end_seg =
zft_last_vtbl->start_seg + num_segments - 1;
} else {
/* `normal', QIC-80 like vtbl
*/
zft_last_vtbl->start_seg = GET2(entry, VTBL_START);
zft_last_vtbl->end_seg = GET2(entry, VTBL_END);
}
zft_eom_vtbl->start_seg = zft_last_vtbl->end_seg + 1;
/* check if we created this volume and get the
* blk_sz
*/
zft_last_vtbl->zft_volume = check_volume(entry, zft_last_vtbl);
if (zft_last_vtbl->zft_volume == 0) {
extract_alien_volume(entry, zft_last_vtbl);
} else {
extract_zft_volume(entry, zft_last_vtbl);
}
DUMP_VOLINFO(ft_t_noise, &entry[VTBL_DESC], zft_last_vtbl);
entry +=VTBL_SIZE;
}
#if 0
/*
* undefine to test end of tape handling
*/
zft_new_vtbl_entry();
zft_last_vtbl->start_seg = zft_eom_vtbl->start_seg;
zft_last_vtbl->end_seg = ft_last_data_segment - 10;
zft_last_vtbl->blk_sz = zft_blk_sz;
zft_last_vtbl->zft_volume = 1;
zft_last_vtbl->qic113 = zft_qic113;
zft_last_vtbl->size = (zft_calc_tape_pos(zft_last_vtbl->end_seg+1)
- zft_calc_tape_pos(zft_last_vtbl->start_seg));
#endif
TRACE_EXIT 0;
}
/* this functions translates the failed_sector_log, misused as
* EOF-marker list, into a virtual volume table. The table mustn't be
* written to tape, because this would occupy the first data segment,
* which should be the volume table, but is actually the first segment
* that is filled with data (when using standard ftape). We assume,
* that we get a non-empty failed_sector_log.
*/
int zft_fake_volume_headers (eof_mark_union *eof_map, int num_failed_sectors)
{
unsigned int segment, sector;
int have_eom = 0;
int vol_no;
TRACE_FUN(ft_t_flow);
if ((num_failed_sectors >= 2) &&
(GET2(&eof_map[num_failed_sectors - 1].mark.segment, 0)
==
GET2(&eof_map[num_failed_sectors - 2].mark.segment, 0) + 1) &&
(GET2(&eof_map[num_failed_sectors - 1].mark.date, 0) == 1)) {
/* this should be eom. We keep the remainder of the
* tape as another volume.
*/
have_eom = 1;
}
zft_init_vtbl();
zft_eom_vtbl->start_seg = ft_first_data_segment;
for(vol_no = 0; vol_no < num_failed_sectors - have_eom; vol_no ++) {
zft_new_vtbl_entry();
segment = GET2(&eof_map[vol_no].mark.segment, 0);
sector = GET2(&eof_map[vol_no].mark.date, 0);
zft_last_vtbl->start_seg = zft_eom_vtbl->start_seg;
zft_last_vtbl->end_seg = segment;
zft_eom_vtbl->start_seg = segment + 1;
zft_last_vtbl->blk_sz = 1;
zft_last_vtbl->size =
(zft_calc_tape_pos(zft_last_vtbl->end_seg)
- zft_calc_tape_pos(zft_last_vtbl->start_seg)
+ (sector-1) * FT_SECTOR_SIZE);
TRACE(ft_t_noise,
"failed sector log: segment: %d, sector: %d",
segment, sector);
DUMP_VOLINFO(ft_t_noise, "Faked volume", zft_last_vtbl);
}
if (!have_eom) {
zft_new_vtbl_entry();
zft_last_vtbl->start_seg = zft_eom_vtbl->start_seg;
zft_last_vtbl->end_seg = ft_last_data_segment;
zft_eom_vtbl->start_seg = ft_last_data_segment + 1;
zft_last_vtbl->size = zft_capacity;
zft_last_vtbl->size -= zft_calc_tape_pos(zft_last_vtbl->start_seg);
zft_last_vtbl->blk_sz = 1;
DUMP_VOLINFO(ft_t_noise, "Faked volume",zft_last_vtbl);
}
TRACE_EXIT 0;
}
/* update the internal volume table
*
* if before start of last volume: erase all following volumes if
* inside a volume: set end of volume to infinity
*
* this function is intended to be called every time _ftape_write() is
* called
*
* return: 0 if no new volume was created, 1 if a new volume was
* created
*
* NOTE: we don't need to check for zft_mode as ftape_write() does
* that already. This function gets never called without accessing
* zftape via the *qft* devices
*/
int zft_open_volume(zft_position *pos, int blk_sz, int use_compression)
{
TRACE_FUN(ft_t_flow);
if (!zft_qic_mode) {
TRACE_EXIT 0;
}
if (zft_tape_at_lbot(pos)) {
zft_init_vtbl();
if(zft_old_ftape) {
/* clear old ftape's eof marks */
zft_clear_ftape_file_marks();
zft_old_ftape = 0; /* no longer old ftape */
}
zft_reset_position(pos);
}
if (pos->seg_pos != zft_last_vtbl->end_seg + 1) {
TRACE_ABORT(-EIO, ft_t_bug,
"BUG: seg_pos: %d, zft_last_vtbl->end_seg: %d",
pos->seg_pos, zft_last_vtbl->end_seg);
}
TRACE(ft_t_noise, "create new volume");
if (zft_eom_vtbl->count >= ZFT_MAX_VOLUMES) {
TRACE_ABORT(-ENOSPC, ft_t_err,
"Error: maxmimal number of volumes exhausted "
"(maxmimum is %d)", ZFT_MAX_VOLUMES);
}
zft_new_vtbl_entry();
pos->volume_pos = pos->seg_byte_pos = 0;
zft_last_vtbl->start_seg = pos->seg_pos;
zft_last_vtbl->end_seg = ft_last_data_segment; /* infinity */
zft_last_vtbl->blk_sz = blk_sz;
zft_last_vtbl->size = zft_capacity;
zft_last_vtbl->zft_volume = 1;
zft_last_vtbl->use_compression = use_compression;
zft_last_vtbl->qic113 = zft_qic113;
zft_last_vtbl->new_volume = 1;
zft_last_vtbl->open = 1;
zft_volume_table_changed = 1;
zft_eom_vtbl->start_seg = ft_last_data_segment + 1;
TRACE_EXIT 0;
}
/* perform mtfsf, mtbsf, not allowed without zft_qic_mode
*/
int zft_skip_volumes(int count, zft_position *pos)
{
const zft_volinfo *vtbl;
TRACE_FUN(ft_t_flow);
TRACE(ft_t_noise, "count: %d", count);
vtbl= zft_find_volume(pos->seg_pos);
while (count > 0 && vtbl != zft_eom_vtbl) {
vtbl = list_entry(vtbl->node.next, zft_volinfo, node);
count --;
}
while (count < 0 && vtbl != zft_first_vtbl) {
vtbl = list_entry(vtbl->node.prev, zft_volinfo, node);
count ++;
}
pos->seg_pos = vtbl->start_seg;
pos->seg_byte_pos = 0;
pos->volume_pos = 0;
pos->tape_pos = zft_calc_tape_pos(pos->seg_pos);
zft_just_before_eof = vtbl->size == 0;
if (zft_cmpr_ops) {
(*zft_cmpr_ops->reset)();
}
zft_deblock_segment = -1; /* no need to keep cache */
TRACE(ft_t_noise, "repositioning to:\n"
KERN_INFO "zft_seg_pos : %d\n"
KERN_INFO "zft_seg_byte_pos : %d\n"
KERN_INFO "zft_tape_pos : " LL_X "\n"
KERN_INFO "zft_volume_pos : " LL_X "\n"
KERN_INFO "file number : %d",
pos->seg_pos, pos->seg_byte_pos,
LL(pos->tape_pos), LL(pos->volume_pos), vtbl->count);
zft_resid = count < 0 ? -count : count;
TRACE_EXIT zft_resid ? -EINVAL : 0;
}
/* the following simply returns the raw data position of the EOM
* marker, MTIOCSIZE ioctl
*/
__s64 zft_get_eom_pos(void)
{
if (zft_qic_mode) {
return zft_calc_tape_pos(zft_eom_vtbl->start_seg);
} else {
/* there is only one volume in raw mode */
return zft_capacity;
}
}
/* skip to eom, used for MTEOM
*/
void zft_skip_to_eom(zft_position *pos)
{
TRACE_FUN(ft_t_flow);
pos->seg_pos = zft_eom_vtbl->start_seg;
pos->seg_byte_pos =
pos->volume_pos =
zft_just_before_eof = 0;
pos->tape_pos = zft_calc_tape_pos(pos->seg_pos);
TRACE(ft_t_noise, "ftape positioned to segment %d, data pos " LL_X,
pos->seg_pos, LL(pos->tape_pos));
TRACE_EXIT;
}
/* write an EOF-marker by setting zft_last_vtbl->end_seg to seg_pos.
* NOTE: this function assumes that zft_last_vtbl points to a valid
* vtbl entry
*
* NOTE: this routine always positions before the EOF marker
*/
int zft_close_volume(zft_position *pos)
{
TRACE_FUN(ft_t_any);
if (zft_vtbl_empty || !zft_last_vtbl->open) { /* should not happen */
TRACE(ft_t_noise, "There are no volumes to finish");
TRACE_EXIT -EIO;
}
if (pos->seg_byte_pos == 0 &&
pos->seg_pos != zft_last_vtbl->start_seg) {
pos->seg_pos --;
pos->seg_byte_pos = zft_get_seg_sz(pos->seg_pos);
}
zft_last_vtbl->end_seg = pos->seg_pos;
zft_last_vtbl->size = pos->volume_pos;
zft_volume_table_changed = 1;
zft_just_before_eof = 1;
zft_eom_vtbl->start_seg = zft_last_vtbl->end_seg + 1;
zft_last_vtbl->open = 0; /* closed */
TRACE_EXIT 0;
}
/* write count file-marks at current position.
*
* The tape is positioned after the eof-marker, that is at byte 0 of
* the segment following the eof-marker
*
* this function is only allowed in zft_qic_mode
*
* Only allowed when tape is at BOT or EOD.
*/
int zft_weof(unsigned int count, zft_position *pos)
{
TRACE_FUN(ft_t_flow);
if (!count) { /* write zero EOF marks should be a real no-op */
TRACE_EXIT 0;
}
zft_volume_table_changed = 1;
if (zft_tape_at_lbot(pos)) {
zft_init_vtbl();
if(zft_old_ftape) {
/* clear old ftape's eof marks */
zft_clear_ftape_file_marks();
zft_old_ftape = 0; /* no longer old ftape */
}
}
if (zft_last_vtbl->open) {
zft_close_volume(pos);
zft_move_past_eof(pos);
count --;
}
/* now it's easy, just append eof-marks, that is empty
* volumes, to the end of the already recorded media.
*/
while (count > 0 &&
pos->seg_pos <= ft_last_data_segment &&
zft_eom_vtbl->count < ZFT_MAX_VOLUMES) {
TRACE(ft_t_noise,
"Writing zero sized file at segment %d", pos->seg_pos);
zft_new_vtbl_entry();
zft_last_vtbl->start_seg = pos->seg_pos;
zft_last_vtbl->end_seg = pos->seg_pos;
zft_last_vtbl->size = 0;
zft_last_vtbl->blk_sz = zft_blk_sz;
zft_last_vtbl->zft_volume = 1;
zft_last_vtbl->use_compression = 0;
pos->tape_pos += zft_get_seg_sz(pos->seg_pos);
zft_eom_vtbl->start_seg = ++ pos->seg_pos;
count --;
}
if (count > 0) {
/* there are two possibilities: end of tape, or the
* maximum number of files is exhausted.
*/
zft_resid = count;
TRACE(ft_t_noise,"Number of marks NOT written: %d", zft_resid);
if (zft_eom_vtbl->count == ZFT_MAX_VOLUMES) {
TRACE_ABORT(-EINVAL, ft_t_warn,
"maximum allowed number of files "
"exhausted: %d", ZFT_MAX_VOLUMES);
} else {
TRACE_ABORT(-ENOSPC,
ft_t_noise, "reached end of tape");
}
}
TRACE_EXIT 0;
}
const zft_volinfo *zft_find_volume(unsigned int seg_pos)
{
TRACE_FUN(ft_t_flow);
TRACE(ft_t_any, "called with seg_pos %d",seg_pos);
if (!zft_qic_mode) {
if (seg_pos > ft_last_data_segment) {
TRACE_EXIT &eot_vtbl;
}
tape_vtbl.blk_sz = zft_blk_sz;
TRACE_EXIT &tape_vtbl;
}
if (seg_pos < zft_first_vtbl->start_seg) {
TRACE_EXIT (cur_vtbl = zft_first_vtbl);
}
while (seg_pos > cur_vtbl->end_seg) {
cur_vtbl = list_entry(cur_vtbl->node.next, zft_volinfo, node);
TRACE(ft_t_noise, "%d - %d", cur_vtbl->start_seg, cur_vtbl->end_seg);
}
while (seg_pos < cur_vtbl->start_seg) {
cur_vtbl = list_entry(cur_vtbl->node.prev, zft_volinfo, node);
TRACE(ft_t_noise, "%d - %d", cur_vtbl->start_seg, cur_vtbl->end_seg);
}
if (seg_pos > cur_vtbl->end_seg || seg_pos < cur_vtbl->start_seg) {
TRACE(ft_t_bug, "This cannot happen");
}
DUMP_VOLINFO(ft_t_noise, "", cur_vtbl);
TRACE_EXIT cur_vtbl;
}
/* this function really assumes that we are just before eof
*/
void zft_move_past_eof(zft_position *pos)
{
TRACE_FUN(ft_t_flow);
TRACE(ft_t_noise, "old seg. pos: %d", pos->seg_pos);
pos->tape_pos += zft_get_seg_sz(pos->seg_pos++) - pos->seg_byte_pos;
pos->seg_byte_pos = 0;
pos->volume_pos = 0;
if (zft_cmpr_ops) {
(*zft_cmpr_ops->reset)();
}
zft_just_before_eof = 0;
zft_deblock_segment = -1; /* no need to cache it anymore */
TRACE(ft_t_noise, "new seg. pos: %d", pos->seg_pos);
TRACE_EXIT;
}
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