ftape-read.c
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- /*
- * Copyright (C) 1993-1996 Bas Laarhoven,
- * (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/lowlevel/ftape-read.c,v $
- * $Revision: 1.6 $
- * $Date: 1997/10/21 14:39:22 $
- *
- * This file contains the reading code
- * for the QIC-117 floppy-tape driver for Linux.
- *
- */
- #include <linux/string.h>
- #include <linux/errno.h>
- #include <linux/mm.h>
- #include <asm/segment.h>
- #include <linux/ftape.h>
- #include <linux/qic117.h>
- #include "../lowlevel/ftape-tracing.h"
- #include "../lowlevel/ftape-read.h"
- #include "../lowlevel/ftape-io.h"
- #include "../lowlevel/ftape-ctl.h"
- #include "../lowlevel/ftape-rw.h"
- #include "../lowlevel/ftape-write.h"
- #include "../lowlevel/ftape-ecc.h"
- #include "../lowlevel/ftape-bsm.h"
- /* Global vars.
- */
- /* Local vars.
- */
- void ftape_zap_read_buffers(void)
- {
- int i;
- for (i = 0; i < ft_nr_buffers; ++i) {
- /* changed to "fit" with dynamic allocation of tape_buffer. --khp */
- ft_buffer[i]->status = waiting;
- ft_buffer[i]->bytes = 0;
- ft_buffer[i]->skip = 0;
- ft_buffer[i]->retry = 0;
- }
- /* ftape_reset_buffer(); */
- }
- static SectorMap convert_sector_map(buffer_struct * buff)
- {
- int i = 0;
- SectorMap bad_map = ftape_get_bad_sector_entry(buff->segment_id);
- SectorMap src_map = buff->soft_error_map | buff->hard_error_map;
- SectorMap dst_map = 0;
- TRACE_FUN(ft_t_any);
- if (bad_map || src_map) {
- TRACE(ft_t_flow, "bad_map = 0x%08lx", (long) bad_map);
- TRACE(ft_t_flow, "src_map = 0x%08lx", (long) src_map);
- }
- while (bad_map) {
- while ((bad_map & 1) == 0) {
- if (src_map & 1) {
- dst_map |= (1 << i);
- }
- src_map >>= 1;
- bad_map >>= 1;
- ++i;
- }
- /* (bad_map & 1) == 1 */
- src_map >>= 1;
- bad_map >>= 1;
- }
- if (src_map) {
- dst_map |= (src_map << i);
- }
- if (dst_map) {
- TRACE(ft_t_flow, "dst_map = 0x%08lx", (long) dst_map);
- }
- TRACE_EXIT dst_map;
- }
- static int correct_and_copy_fraction(buffer_struct *buff, __u8 * destination,
- int start, int size)
- {
- struct memory_segment mseg;
- int result;
- SectorMap read_bad;
- TRACE_FUN(ft_t_any);
- mseg.read_bad = convert_sector_map(buff);
- mseg.marked_bad = 0; /* not used... */
- mseg.blocks = buff->bytes / FT_SECTOR_SIZE;
- mseg.data = buff->address;
- /* If there are no data sectors we can skip this segment.
- */
- if (mseg.blocks <= 3) {
- TRACE_ABORT(0, ft_t_noise, "empty segment");
- }
- read_bad = mseg.read_bad;
- ft_history.crc_errors += count_ones(read_bad);
- result = ftape_ecc_correct_data(&mseg);
- if (read_bad != 0 || mseg.corrected != 0) {
- TRACE(ft_t_noise, "crc error map: 0x%08lx", (unsigned long)read_bad);
- TRACE(ft_t_noise, "corrected map: 0x%08lx", (unsigned long)mseg.corrected);
- ft_history.corrected += count_ones(mseg.corrected);
- }
- if (result == ECC_CORRECTED || result == ECC_OK) {
- if (result == ECC_CORRECTED) {
- TRACE(ft_t_info, "ecc corrected segment: %d", buff->segment_id);
- }
- if(start < 0) {
- start= 0;
- }
- if((start+size) > ((mseg.blocks - 3) * FT_SECTOR_SIZE)) {
- size = (mseg.blocks - 3) * FT_SECTOR_SIZE - start;
- }
- if (size < 0) {
- size= 0;
- }
- if(size > 0) {
- memcpy(destination + start, mseg.data + start, size);
- }
- if ((read_bad ^ mseg.corrected) & mseg.corrected) {
- /* sectors corrected without crc errors set */
- ft_history.crc_failures++;
- }
- TRACE_EXIT size; /* (mseg.blocks - 3) * FT_SECTOR_SIZE; */
- } else {
- ft_history.ecc_failures++;
- TRACE_ABORT(-EAGAIN,
- ft_t_err, "ecc failure on segment %d",
- buff->segment_id);
- }
- TRACE_EXIT 0;
- }
- /* Read given segment into buffer at address.
- */
- int ftape_read_segment_fraction(const int segment_id,
- void *address,
- const ft_read_mode_t read_mode,
- const int start,
- const int size)
- {
- int result = 0;
- int retry = 0;
- int bytes_read = 0;
- int read_done = 0;
- TRACE_FUN(ft_t_flow);
- ft_history.used |= 1;
- TRACE(ft_t_data_flow, "segment_id = %d", segment_id);
- if (ft_driver_state != reading) {
- TRACE(ft_t_noise, "calling ftape_abort_operation");
- TRACE_CATCH(ftape_abort_operation(),);
- ftape_set_state(reading);
- }
- for(;;) {
- buffer_struct *tail;
- /* Allow escape from this loop on signal !
- */
- FT_SIGNAL_EXIT(_DONT_BLOCK);
- /* Search all full buffers for the first matching the
- * wanted segment. Clear other buffers on the fly.
- */
- tail = ftape_get_buffer(ft_queue_tail);
- while (!read_done && tail->status == done) {
- /* Allow escape from this loop on signal !
- */
- FT_SIGNAL_EXIT(_DONT_BLOCK);
- if (tail->segment_id == segment_id) {
- /* If out buffer is already full,
- * return its contents.
- */
- TRACE(ft_t_flow, "found segment in cache: %d",
- segment_id);
- if (tail->deleted) {
- /* Return a value that
- * read_header_segment
- * understands. As this
- * should only occur when
- * searching for the header
- * segments it shouldn't be
- * misinterpreted elsewhere.
- */
- TRACE_EXIT 0;
- }
- result = correct_and_copy_fraction(
- tail,
- address,
- start,
- size);
- TRACE(ft_t_flow, "segment contains (bytes): %d",
- result);
- if (result < 0) {
- if (result != -EAGAIN) {
- TRACE_EXIT result;
- }
- /* keep read_done == 0, will
- * trigger
- * ftape_abort_operation
- * because reading wrong
- * segment.
- */
- TRACE(ft_t_err, "ecc failed, retry");
- ++retry;
- } else {
- read_done = 1;
- bytes_read = result;
- }
- } else {
- TRACE(ft_t_flow,"zapping segment in cache: %d",
- tail->segment_id);
- }
- tail->status = waiting;
- tail = ftape_next_buffer(ft_queue_tail);
- }
- if (!read_done && tail->status == reading) {
- if (tail->segment_id == segment_id) {
- switch(ftape_wait_segment(reading)) {
- case 0:
- break;
- case -EINTR:
- TRACE_ABORT(-EINTR, ft_t_warn,
- "interrupted by "
- "non-blockable signal");
- break;
- default:
- TRACE(ft_t_noise,
- "wait_segment failed");
- ftape_abort_operation();
- ftape_set_state(reading);
- break;
- }
- } else {
- /* We're reading the wrong segment,
- * stop runner.
- */
- TRACE(ft_t_noise, "reading wrong segment");
- ftape_abort_operation();
- ftape_set_state(reading);
- }
- }
- /* should runner stop ?
- */
- if (ft_runner_status == aborting) {
- buffer_struct *head = ftape_get_buffer(ft_queue_head);
- switch(head->status) {
- case error:
- ft_history.defects +=
- count_ones(head->hard_error_map);
- case reading:
- head->status = waiting;
- break;
- default:
- break;
- }
- TRACE_CATCH(ftape_dumb_stop(),);
- } else {
- /* If just passed last segment on tape: wait
- * for BOT or EOT mark. Sets ft_runner_status to
- * idle if at lEOT and successful
- */
- TRACE_CATCH(ftape_handle_logical_eot(),);
- }
- /* If we got a segment: quit, or else retry up to limit.
- *
- * If segment to read is empty, do not start runner for it,
- * but wait for next read call.
- */
- if (read_done ||
- ftape_get_bad_sector_entry(segment_id) == EMPTY_SEGMENT ) {
- /* bytes_read = 0; should still be zero */
- TRACE_EXIT bytes_read;
- }
- if (retry > FT_RETRIES_ON_ECC_ERROR) {
- ft_history.defects++;
- TRACE_ABORT(-ENODATA, ft_t_err,
- "too many retries on ecc failure");
- }
- /* Now at least one buffer is empty !
- * Restart runner & tape if needed.
- */
- TRACE(ft_t_any, "head: %d, tail: %d, ft_runner_status: %d",
- ftape_buffer_id(ft_queue_head),
- ftape_buffer_id(ft_queue_tail),
- ft_runner_status);
- TRACE(ft_t_any, "buffer[].status, [head]: %d, [tail]: %d",
- ftape_get_buffer(ft_queue_head)->status,
- ftape_get_buffer(ft_queue_tail)->status);
- tail = ftape_get_buffer(ft_queue_tail);
- if (tail->status == waiting) {
- buffer_struct *head = ftape_get_buffer(ft_queue_head);
- ftape_setup_new_segment(head, segment_id, -1);
- if (read_mode == FT_RD_SINGLE) {
- /* disable read-ahead */
- head->next_segment = 0;
- }
- ftape_calc_next_cluster(head);
- if (ft_runner_status == idle) {
- result = ftape_start_tape(segment_id,
- head->sector_offset);
- if (result < 0) {
- TRACE_ABORT(result, ft_t_err, "Error: "
- "segment %d unreachable",
- segment_id);
- }
- }
- head->status = reading;
- fdc_setup_read_write(head, FDC_READ);
- }
- }
- /* not reached */
- TRACE_EXIT -EIO;
- }
- int ftape_read_header_segment(__u8 *address)
- {
- int result;
- int header_segment;
- int first_failed = 0;
- int status;
- TRACE_FUN(ft_t_flow);
- ft_used_header_segment = -1;
- TRACE_CATCH(ftape_report_drive_status(&status),);
- TRACE(ft_t_flow, "reading...");
- /* We're looking for the first header segment.
- * A header segment cannot contain bad sectors, therefor at the
- * tape start, segments with bad sectors are (according to QIC-40/80)
- * written with deleted data marks and must be skipped.
- */
- memset(address, ' ', (FT_SECTORS_PER_SEGMENT - 3) * FT_SECTOR_SIZE);
- result = 0;
- #define HEADER_SEGMENT_BOUNDARY 68 /* why not 42? */
- for (header_segment = 0;
- header_segment < HEADER_SEGMENT_BOUNDARY && result == 0;
- ++header_segment) {
- /* Set no read-ahead, the isr will force read-ahead whenever
- * it encounters deleted data !
- */
- result = ftape_read_segment(header_segment,
- address,
- FT_RD_SINGLE);
- if (result < 0 && !first_failed) {
- TRACE(ft_t_err, "header segment damaged, trying backup");
- first_failed = 1;
- result = 0; /* force read of next (backup) segment */
- }
- }
- if (result < 0 || header_segment >= HEADER_SEGMENT_BOUNDARY) {
- TRACE_ABORT(-EIO, ft_t_err,
- "no readable header segment found");
- }
- TRACE_CATCH(ftape_abort_operation(),);
- ft_used_header_segment = header_segment;
- result = ftape_decode_header_segment(address);
- TRACE_EXIT result;
- }
- int ftape_decode_header_segment(__u8 *address)
- {
- unsigned int max_floppy_side;
- unsigned int max_floppy_track;
- unsigned int max_floppy_sector;
- unsigned int new_tape_len;
- TRACE_FUN(ft_t_flow);
- if (GET4(address, FT_SIGNATURE) == FT_D2G_MAGIC) {
- /* Ditto 2GB header segment. They encrypt the bad sector map.
- * We decrypt it and store them in normal format.
- * I hope this is correct.
- */
- int i;
- TRACE(ft_t_warn,
- "Found Ditto 2GB tape, "
- "trying to decrypt bad sector map");
- for (i=256; i < 29 * FT_SECTOR_SIZE; i++) {
- address[i] = ~(address[i] - (i&0xff));
- }
- PUT4(address, 0,FT_HSEG_MAGIC);
- } else if (GET4(address, FT_SIGNATURE) != FT_HSEG_MAGIC) {
- TRACE_ABORT(-EIO, ft_t_err,
- "wrong signature in header segment");
- }
- ft_format_code = (ft_format_type) address[FT_FMT_CODE];
- if (ft_format_code != fmt_big) {
- ft_header_segment_1 = GET2(address, FT_HSEG_1);
- ft_header_segment_2 = GET2(address, FT_HSEG_2);
- ft_first_data_segment = GET2(address, FT_FRST_SEG);
- ft_last_data_segment = GET2(address, FT_LAST_SEG);
- } else {
- ft_header_segment_1 = GET4(address, FT_6_HSEG_1);
- ft_header_segment_2 = GET4(address, FT_6_HSEG_2);
- ft_first_data_segment = GET4(address, FT_6_FRST_SEG);
- ft_last_data_segment = GET4(address, FT_6_LAST_SEG);
- }
- TRACE(ft_t_noise, "first data segment: %d", ft_first_data_segment);
- TRACE(ft_t_noise, "last data segment: %d", ft_last_data_segment);
- TRACE(ft_t_noise, "header segments are %d and %d",
- ft_header_segment_1, ft_header_segment_2);
- /* Verify tape parameters...
- * QIC-40/80 spec: tape_parameters:
- *
- * segments-per-track segments_per_track
- * tracks-per-cartridge tracks_per_tape
- * max-floppy-side (segments_per_track *
- * tracks_per_tape - 1) /
- * ftape_segments_per_head
- * max-floppy-track ftape_segments_per_head /
- * ftape_segments_per_cylinder - 1
- * max-floppy-sector ftape_segments_per_cylinder *
- * FT_SECTORS_PER_SEGMENT
- */
- ft_segments_per_track = GET2(address, FT_SPT);
- ft_tracks_per_tape = address[FT_TPC];
- max_floppy_side = address[FT_FHM];
- max_floppy_track = address[FT_FTM];
- max_floppy_sector = address[FT_FSM];
- TRACE(ft_t_noise, "(fmt/spt/tpc/fhm/ftm/fsm) = %d/%d/%d/%d/%d/%d",
- ft_format_code, ft_segments_per_track, ft_tracks_per_tape,
- max_floppy_side, max_floppy_track, max_floppy_sector);
- new_tape_len = ftape_tape_len;
- switch (ft_format_code) {
- case fmt_425ft:
- new_tape_len = 425;
- break;
- case fmt_normal:
- if (ftape_tape_len == 0) { /* otherwise 307 ft */
- new_tape_len = 205;
- }
- break;
- case fmt_1100ft:
- new_tape_len = 1100;
- break;
- case fmt_var:{
- int segments_per_1000_inch = 1; /* non-zero default for switch */
- switch (ft_qic_std) {
- case QIC_TAPE_QIC40:
- segments_per_1000_inch = 332;
- break;
- case QIC_TAPE_QIC80:
- segments_per_1000_inch = 488;
- break;
- case QIC_TAPE_QIC3010:
- segments_per_1000_inch = 730;
- break;
- case QIC_TAPE_QIC3020:
- segments_per_1000_inch = 1430;
- break;
- }
- new_tape_len = (1000 * ft_segments_per_track +
- (segments_per_1000_inch - 1)) / segments_per_1000_inch;
- break;
- }
- case fmt_big:{
- int segments_per_1000_inch = 1; /* non-zero default for switch */
- switch (ft_qic_std) {
- case QIC_TAPE_QIC40:
- segments_per_1000_inch = 332;
- break;
- case QIC_TAPE_QIC80:
- segments_per_1000_inch = 488;
- break;
- case QIC_TAPE_QIC3010:
- segments_per_1000_inch = 730;
- break;
- case QIC_TAPE_QIC3020:
- segments_per_1000_inch = 1430;
- break;
- default:
- TRACE_ABORT(-EIO, ft_t_bug,
- "%x QIC-standard with fmt-code %d, please report",
- ft_qic_std, ft_format_code);
- }
- new_tape_len = ((1000 * ft_segments_per_track +
- (segments_per_1000_inch - 1)) /
- segments_per_1000_inch);
- break;
- }
- default:
- TRACE_ABORT(-EIO, ft_t_err,
- "unknown tape format, please report !");
- }
- if (new_tape_len != ftape_tape_len) {
- ftape_tape_len = new_tape_len;
- TRACE(ft_t_info, "calculated tape length is %d ft",
- ftape_tape_len);
- ftape_calc_timeouts(ft_qic_std, ft_data_rate, ftape_tape_len);
- }
- if (ft_segments_per_track == 0 && ft_tracks_per_tape == 0 &&
- max_floppy_side == 0 && max_floppy_track == 0 &&
- max_floppy_sector == 0) {
- /* QIC-40 Rev E and earlier has no values in the header.
- */
- ft_segments_per_track = 68;
- ft_tracks_per_tape = 20;
- max_floppy_side = 1;
- max_floppy_track = 169;
- max_floppy_sector = 128;
- }
- /* This test will compensate for the wrong parameter on tapes
- * formatted by Conner software.
- */
- if (ft_segments_per_track == 150 &&
- ft_tracks_per_tape == 28 &&
- max_floppy_side == 7 &&
- max_floppy_track == 149 &&
- max_floppy_sector == 128) {
- TRACE(ft_t_info, "the famous CONNER bug: max_floppy_side off by one !");
- max_floppy_side = 6;
- }
- /* These tests will compensate for the wrong parameter on tapes
- * formatted by ComByte Windows software.
- *
- * First, for 205 foot tapes
- */
- if (ft_segments_per_track == 100 &&
- ft_tracks_per_tape == 28 &&
- max_floppy_side == 9 &&
- max_floppy_track == 149 &&
- max_floppy_sector == 128) {
- TRACE(ft_t_info, "the ComByte bug: max_floppy_side incorrect!");
- max_floppy_side = 4;
- }
- /* Next, for 307 foot tapes. */
- if (ft_segments_per_track == 150 &&
- ft_tracks_per_tape == 28 &&
- max_floppy_side == 9 &&
- max_floppy_track == 149 &&
- max_floppy_sector == 128) {
- TRACE(ft_t_info, "the ComByte bug: max_floppy_side incorrect!");
- max_floppy_side = 6;
- }
- /* This test will compensate for the wrong parameter on tapes
- * formatted by Colorado Windows software.
- */
- if (ft_segments_per_track == 150 &&
- ft_tracks_per_tape == 28 &&
- max_floppy_side == 6 &&
- max_floppy_track == 150 &&
- max_floppy_sector == 128) {
- TRACE(ft_t_info, "the famous Colorado bug: max_floppy_track off by one !");
- max_floppy_track = 149;
- }
- ftape_segments_per_head = ((max_floppy_sector/FT_SECTORS_PER_SEGMENT) *
- (max_floppy_track + 1));
- /* This test will compensate for some bug reported by Dima
- * Brodsky. Seems to be a Colorado bug, either. (freebee
- * Imation tape shipped together with Colorado T3000
- */
- if ((ft_format_code == fmt_var || ft_format_code == fmt_big) &&
- ft_tracks_per_tape == 50 &&
- max_floppy_side == 54 &&
- max_floppy_track == 255 &&
- max_floppy_sector == 128) {
- TRACE(ft_t_info, "the famous ??? bug: max_floppy_track off by one !");
- max_floppy_track = 254;
- }
- /*
- * Verify drive_configuration with tape parameters
- */
- if (ftape_segments_per_head == 0 || ftape_segments_per_cylinder == 0 ||
- ((ft_segments_per_track * ft_tracks_per_tape - 1) / ftape_segments_per_head
- != max_floppy_side) ||
- (ftape_segments_per_head / ftape_segments_per_cylinder - 1 != max_floppy_track) ||
- (ftape_segments_per_cylinder * FT_SECTORS_PER_SEGMENT != max_floppy_sector)
- #ifdef TESTING
- || ((ft_format_code == fmt_var || ft_format_code == fmt_big) &&
- (max_floppy_track != 254 || max_floppy_sector != 128))
- #endif
- ) {
- TRACE(ft_t_err,"Tape parameters inconsistency, please report");
- TRACE(ft_t_err, "reported = %d/%d/%d/%d/%d/%d",
- ft_format_code,
- ft_segments_per_track,
- ft_tracks_per_tape,
- max_floppy_side,
- max_floppy_track,
- max_floppy_sector);
- TRACE(ft_t_err, "required = %d/%d/%d/%d/%d/%d",
- ft_format_code,
- ft_segments_per_track,
- ft_tracks_per_tape,
- ((ft_segments_per_track * ft_tracks_per_tape -1) /
- ftape_segments_per_head ),
- (ftape_segments_per_head /
- ftape_segments_per_cylinder - 1 ),
- (ftape_segments_per_cylinder * FT_SECTORS_PER_SEGMENT));
- TRACE_EXIT -EIO;
- }
- ftape_extract_bad_sector_map(address);
- TRACE_EXIT 0;
- }