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/*
* Copyright (C) 1993-1995 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-write.c,v $
* $Revision: 1.3.4.1 $
* $Date: 1997/11/14 18:07:04 $
*
* This file contains the writing 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-write.h"
#include "../lowlevel/ftape-read.h"
#include "../lowlevel/ftape-io.h"
#include "../lowlevel/ftape-ctl.h"
#include "../lowlevel/ftape-rw.h"
#include "../lowlevel/ftape-ecc.h"
#include "../lowlevel/ftape-bsm.h"
#include "../lowlevel/fdc-isr.h"
/* Global vars.
*/
/* Local vars.
*/
static int last_write_failed;
void ftape_zap_write_buffers(void)
{
int i;
for (i = 0; i < ft_nr_buffers; ++i) {
ft_buffer[i]->status = done;
}
ftape_reset_buffer();
}
static int copy_and_gen_ecc(void *destination,
const void *source,
const SectorMap bad_sector_map)
{
int result;
struct memory_segment mseg;
int bads = count_ones(bad_sector_map);
TRACE_FUN(ft_t_any);
if (bads > 0) {
TRACE(ft_t_noise, "bad sectors in map: %d", bads);
}
if (bads + 3 >= FT_SECTORS_PER_SEGMENT) {
TRACE(ft_t_noise, "empty segment");
mseg.blocks = 0; /* skip entire segment */
result = 0; /* nothing written */
} else {
mseg.blocks = FT_SECTORS_PER_SEGMENT - bads;
mseg.data = destination;
memcpy(mseg.data, source, (mseg.blocks - 3) * FT_SECTOR_SIZE);
result = ftape_ecc_set_segment_parity(&mseg);
if (result < 0) {
TRACE(ft_t_err, "ecc_set_segment_parity failed");
} else {
result = (mseg.blocks - 3) * FT_SECTOR_SIZE;
}
}
TRACE_EXIT result;
}
int ftape_start_writing(const ft_write_mode_t mode)
{
buffer_struct *head = ftape_get_buffer(ft_queue_head);
int segment_id = head->segment_id;
int result;
buffer_state_enum wanted_state = (mode == FT_WR_DELETE
? deleting
: writing);
TRACE_FUN(ft_t_flow);
if ((ft_driver_state != wanted_state) || head->status != waiting) {
TRACE_EXIT 0;
}
ftape_setup_new_segment(head, segment_id, 1);
if (mode == FT_WR_SINGLE) {
/* stop tape instead of pause */
head->next_segment = 0;
}
ftape_calc_next_cluster(head); /* prepare */
head->status = ft_driver_state; /* either writing or deleting */
if (ft_runner_status == idle) {
TRACE(ft_t_noise,
"starting runner for segment %d", segment_id);
TRACE_CATCH(ftape_start_tape(segment_id,head->sector_offset),);
} else {
TRACE(ft_t_noise, "runner not idle, not starting tape");
}
/* go */
result = fdc_setup_read_write(head, (mode == FT_WR_DELETE
? FDC_WRITE_DELETED : FDC_WRITE));
ftape_set_state(wanted_state); /* should not be necessary */
TRACE_EXIT result;
}
/* Wait until all data is actually written to tape.
*
* There is a problem: when the tape runs into logical EOT, then this
* failes. We need to restart the runner in this case.
*/
int ftape_loop_until_writes_done(void)
{
buffer_struct *head;
TRACE_FUN(ft_t_flow);
while ((ft_driver_state == writing || ft_driver_state == deleting) &&
ftape_get_buffer(ft_queue_head)->status != done) {
/* set the runner status to idle if at lEOT */
TRACE_CATCH(ftape_handle_logical_eot(), last_write_failed = 1);
/* restart the tape if necessary */
if (ft_runner_status == idle) {
TRACE(ft_t_noise, "runner is idle, restarting");
if (ft_driver_state == deleting) {
TRACE_CATCH(ftape_start_writing(FT_WR_DELETE),
last_write_failed = 1);
} else {
TRACE_CATCH(ftape_start_writing(FT_WR_MULTI),
last_write_failed = 1);
}
}
TRACE(ft_t_noise, "tail: %d, head: %d",
ftape_buffer_id(ft_queue_tail),
ftape_buffer_id(ft_queue_head));
TRACE_CATCH(fdc_interrupt_wait(5 * FT_SECOND),
last_write_failed = 1);
head = ftape_get_buffer(ft_queue_head);
if (head->status == error) {
/* Allow escape from loop when signaled !
*/
FT_SIGNAL_EXIT(_DONT_BLOCK);
if (head->hard_error_map != 0) {
/* Implement hard write error recovery here
*/
}
/* retry this one */
head->status = waiting;
if (ft_runner_status == aborting) {
ftape_dumb_stop();
}
if (ft_runner_status != idle) {
TRACE_ABORT(-EIO, ft_t_err,
"unexpected state: "
"ft_runner_status != idle");
}
ftape_start_writing(ft_driver_state == deleting
? FT_WR_MULTI : FT_WR_DELETE);
}
TRACE(ft_t_noise, "looping until writes done");
}
ftape_set_state(idle);
TRACE_EXIT 0;
}
/* Write given segment from buffer at address to tape.
*/
static int write_segment(const int segment_id,
const void *address,
const ft_write_mode_t write_mode)
{
int bytes_written = 0;
buffer_struct *tail;
buffer_state_enum wanted_state = (write_mode == FT_WR_DELETE
? deleting : writing);
TRACE_FUN(ft_t_flow);
TRACE(ft_t_noise, "segment_id = %d", segment_id);
if (ft_driver_state != wanted_state) {
if (ft_driver_state == deleting ||
wanted_state == deleting) {
TRACE_CATCH(ftape_loop_until_writes_done(),);
}
TRACE(ft_t_noise, "calling ftape_abort_operation");
TRACE_CATCH(ftape_abort_operation(),);
ftape_zap_write_buffers();
ftape_set_state(wanted_state);
}
/* if all buffers full we'll have to wait...
*/
ftape_wait_segment(wanted_state);
tail = ftape_get_buffer(ft_queue_tail);
switch(tail->status) {
case done:
ft_history.defects += count_ones(tail->hard_error_map);
break;
case waiting:
/* this could happen with multiple EMPTY_SEGMENTs, but
* shouldn't happen any more as we re-start the runner even
* with an empty segment.
*/
bytes_written = -EAGAIN;
break;
case error:
/* setup for a retry
*/
tail->status = waiting;
bytes_written = -EAGAIN; /* force retry */
if (tail->hard_error_map != 0) {
TRACE(ft_t_warn,
"warning: %d hard error(s) in written segment",
count_ones(tail->hard_error_map));
TRACE(ft_t_noise, "hard_error_map = 0x%08lx",
(long)tail->hard_error_map);
/* Implement hard write error recovery here
*/
}
break;
default:
TRACE_ABORT(-EIO, ft_t_err,
"wait for empty segment failed, tail status: %d",
tail->status);
}
/* should runner stop ?
*/
if (ft_runner_status == aborting) {
buffer_struct *head = ftape_get_buffer(ft_queue_head);
if (head->status == wanted_state) {
head->status = done; /* ???? */
}
/* don't call abort_operation(), we don't want to zap
* the dma buffers
*/
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 (tail->status == done) {
/* now at least one buffer is empty, fill it with our
* data. skip bad sectors and generate ecc.
* copy_and_gen_ecc return nr of bytes written, range
* 0..29 Kb inclusive!
*
* Empty segments are handled inside coyp_and_gen_ecc()
*/
if (write_mode != FT_WR_DELETE) {
TRACE_CATCH(bytes_written = copy_and_gen_ecc(
tail->address, address,
ftape_get_bad_sector_entry(segment_id)),);
}
tail->segment_id = segment_id;
tail->status = waiting;
tail = ftape_next_buffer(ft_queue_tail);
}
/* Start tape only if all buffers full or flush mode.
* This will give higher probability of streaming.
*/
if (ft_runner_status != running &&
((tail->status == waiting &&
ftape_get_buffer(ft_queue_head) == tail) ||
write_mode != FT_WR_ASYNC)) {
TRACE_CATCH(ftape_start_writing(write_mode),);
}
TRACE_EXIT bytes_written;
}
/* Write as much as fits from buffer to the given segment on tape
* and handle retries.
* Return the number of bytes written (>= 0), or:
* -EIO write failed
* -EINTR interrupted by signal
* -ENOSPC device full
*/
int ftape_write_segment(const int segment_id,
const void *buffer,
const ft_write_mode_t flush)
{
int retry = 0;
int result;
TRACE_FUN(ft_t_flow);
ft_history.used |= 2;
if (segment_id >= ft_tracks_per_tape*ft_segments_per_track) {
/* tape full */
TRACE_ABORT(-ENOSPC, ft_t_err,
"invalid segment id: %d (max %d)",
segment_id,
ft_tracks_per_tape * ft_segments_per_track -1);
}
for (;;) {
if ((result = write_segment(segment_id, buffer, flush)) >= 0) {
if (result == 0) { /* empty segment */
TRACE(ft_t_noise,
"empty segment, nothing written");
}
TRACE_EXIT result;
}
if (result == -EAGAIN) {
if (++retry > 100) { /* give up */
TRACE_ABORT(-EIO, ft_t_err,
"write failed, >100 retries in segment");
}
TRACE(ft_t_warn, "write error, retry %d (%d)",
retry,
ftape_get_buffer(ft_queue_tail)->segment_id);
} else {
TRACE_ABORT(result, ft_t_err,
"write_segment failed, error: %d", result);
}
/* Allow escape from loop when signaled !
*/
FT_SIGNAL_EXIT(_DONT_BLOCK);
}
}
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