diff options
Diffstat (limited to 'drivers/char/ftape/zftape/zftape-vtbl.c')
| -rw-r--r-- | drivers/char/ftape/zftape/zftape-vtbl.c | 757 |
1 files changed, 757 insertions, 0 deletions
diff --git a/drivers/char/ftape/zftape/zftape-vtbl.c b/drivers/char/ftape/zftape/zftape-vtbl.c new file mode 100644 index 000000000000..ad7f8be6340b --- /dev/null +++ b/drivers/char/ftape/zftape/zftape-vtbl.c @@ -0,0 +1,757 @@ +/* + * 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; +} |