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-rw-r--r--drivers/char/ftape/lowlevel/ftape-write.c336
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diff --git a/drivers/char/ftape/lowlevel/ftape-write.c b/drivers/char/ftape/lowlevel/ftape-write.c
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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 <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);
+ }
+}