kernel-ark/drivers/char/ftape/lowlevel/ftape-format.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

345 lines
9.8 KiB
C

/*
* Copyright (C) 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-format.c,v $
* $Revision: 1.2.4.1 $
* $Date: 1997/11/14 16:05:39 $
*
* This file contains the code to support formatting of floppy
* tape cartridges with the QIC-40/80/3010/3020 floppy-tape
* driver "ftape" for Linux.
*/
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/ftape.h>
#include <linux/qic117.h>
#include "../lowlevel/ftape-tracing.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/ftape-format.h"
#if defined(TESTING)
#define FT_FMT_SEGS_PER_BUF 50
#else
#define FT_FMT_SEGS_PER_BUF (FT_BUFF_SIZE/(4*FT_SECTORS_PER_SEGMENT))
#endif
static spinlock_t ftape_format_lock;
/*
* first segment of the new buffer
*/
static int switch_segment;
/*
* at most 256 segments fit into one 32 kb buffer. Even TR-1 cartridges have
* more than this many segments per track, so better be careful.
*
* buffer_struct *buff: buffer to store the formatting coordinates in
* int start: starting segment for this buffer.
* int spt: segments per track
*
* Note: segment ids are relative to the start of the track here.
*/
static void setup_format_buffer(buffer_struct *buff, int start, int spt,
__u8 gap3)
{
int to_do = spt - start;
TRACE_FUN(ft_t_flow);
if (to_do > FT_FMT_SEGS_PER_BUF) {
to_do = FT_FMT_SEGS_PER_BUF;
}
buff->ptr = buff->address;
buff->remaining = to_do * FT_SECTORS_PER_SEGMENT; /* # sectors */
buff->bytes = buff->remaining * 4; /* need 4 bytes per sector */
buff->gap3 = gap3;
buff->segment_id = start;
buff->next_segment = start + to_do;
if (buff->next_segment >= spt) {
buff->next_segment = 0; /* 0 means: stop runner */
}
buff->status = waiting; /* tells the isr that it can use
* this buffer
*/
TRACE_EXIT;
}
/*
* start formatting a new track.
*/
int ftape_format_track(const unsigned int track, const __u8 gap3)
{
unsigned long flags;
buffer_struct *tail, *head;
int status;
TRACE_FUN(ft_t_flow);
TRACE_CATCH(ftape_ready_wait(ftape_timeout.pause, &status),);
if (track & 1) {
if (!(status & QIC_STATUS_AT_EOT)) {
TRACE_CATCH(ftape_seek_to_eot(),);
}
} else {
if (!(status & QIC_STATUS_AT_BOT)) {
TRACE_CATCH(ftape_seek_to_bot(),);
}
}
ftape_abort_operation(); /* this sets ft_head = ft_tail = 0 */
ftape_set_state(formatting);
TRACE(ft_t_noise,
"Formatting track %d, logical: from segment %d to %d",
track, track * ft_segments_per_track,
(track + 1) * ft_segments_per_track - 1);
/*
* initialize the buffer switching protocol for this track
*/
head = ftape_get_buffer(ft_queue_head); /* tape isn't running yet */
tail = ftape_get_buffer(ft_queue_tail); /* tape isn't running yet */
switch_segment = 0;
do {
FT_SIGNAL_EXIT(_DONT_BLOCK);
setup_format_buffer(tail, switch_segment,
ft_segments_per_track, gap3);
switch_segment = tail->next_segment;
} while ((switch_segment != 0) &&
((tail = ftape_next_buffer(ft_queue_tail)) != head));
/* go */
head->status = formatting;
TRACE_CATCH(ftape_seek_head_to_track(track),);
TRACE_CATCH(ftape_command(QIC_LOGICAL_FORWARD),);
spin_lock_irqsave(&ftape_format_lock, flags);
TRACE_CATCH(fdc_setup_formatting(head), restore_flags(flags));
spin_unlock_irqrestore(&ftape_format_lock, flags);
TRACE_EXIT 0;
}
/* return segment id of segment currently being formatted and do the
* buffer switching stuff.
*/
int ftape_format_status(unsigned int *segment_id)
{
buffer_struct *tail = ftape_get_buffer(ft_queue_tail);
int result;
TRACE_FUN(ft_t_flow);
while (switch_segment != 0 &&
ftape_get_buffer(ft_queue_head) != tail) {
FT_SIGNAL_EXIT(_DONT_BLOCK);
/* need more buffers, first wait for empty buffer
*/
TRACE_CATCH(ftape_wait_segment(formatting),);
/* don't worry for gap3. If we ever hit this piece of code,
* then all buffer already have the correct gap3 set!
*/
setup_format_buffer(tail, switch_segment,
ft_segments_per_track, tail->gap3);
switch_segment = tail->next_segment;
if (switch_segment != 0) {
tail = ftape_next_buffer(ft_queue_tail);
}
}
/* should runner stop ?
*/
if (ft_runner_status == aborting || ft_runner_status == do_abort) {
buffer_struct *head = ftape_get_buffer(ft_queue_head);
TRACE(ft_t_warn, "Error formatting segment %d",
ftape_get_buffer(ft_queue_head)->segment_id);
(void)ftape_abort_operation();
TRACE_EXIT (head->status != error) ? -EAGAIN : -EIO;
}
/*
* don't care if the timer expires, this is just kind of a
* "select" operation that lets the calling process sleep
* until something has happened
*/
if (fdc_interrupt_wait(5 * FT_SECOND) < 0) {
TRACE(ft_t_noise, "End of track %d at segment %d",
ft_location.track,
ftape_get_buffer(ft_queue_head)->segment_id);
result = 1; /* end of track, unlock module */
} else {
result = 0;
}
/*
* the calling process should use the seg id to determine
* which parts of the dma buffers can be safely overwritten
* with new data.
*/
*segment_id = ftape_get_buffer(ft_queue_head)->segment_id;
/*
* Internally we start counting segment ids from the start of
* each track when formatting, but externally we keep them
* relative to the start of the tape:
*/
*segment_id += ft_location.track * ft_segments_per_track;
TRACE_EXIT result;
}
/*
* The segment id is relative to the start of the tape
*/
int ftape_verify_segment(const unsigned int segment_id, SectorMap *bsm)
{
int result;
int verify_done = 0;
TRACE_FUN(ft_t_flow);
TRACE(ft_t_noise, "Verifying segment %d", segment_id);
if (ft_driver_state != verifying) {
TRACE(ft_t_noise, "calling ftape_abort_operation");
if (ftape_abort_operation() < 0) {
TRACE(ft_t_err, "ftape_abort_operation failed");
TRACE_EXIT -EIO;
}
}
*bsm = 0x00000000;
ftape_set_state(verifying);
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 (!verify_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->soft_error_map |
tail->hard_error_map) != 0) {
TRACE(ft_t_info,"bsm[%d] = 0x%08lx",
segment_id,
(unsigned long)
(tail->soft_error_map |
tail->hard_error_map));
*bsm = (tail->soft_error_map |
tail->hard_error_map);
}
verify_done = 1;
} else {
TRACE(ft_t_flow,"zapping segment in cache: %d",
tail->segment_id);
}
tail->status = waiting;
tail = ftape_next_buffer(ft_queue_tail);
}
if (!verify_done && tail->status == verifying) {
if (tail->segment_id == segment_id) {
switch(ftape_wait_segment(verifying)) {
case 0:
break;
case -EINTR:
TRACE_ABORT(-EINTR, ft_t_warn,
"interrupted by "
"non-blockable signal");
break;
default:
ftape_abort_operation();
ftape_set_state(verifying);
/* be picky */
TRACE_ABORT(-EIO, ft_t_warn,
"wait_segment failed");
}
} else {
/* We're reading the wrong segment,
* stop runner.
*/
TRACE(ft_t_noise, "verifying wrong segment");
ftape_abort_operation();
ftape_set_state(verifying);
}
}
/* should runner stop ?
*/
if (ft_runner_status == aborting) {
buffer_struct *head = ftape_get_buffer(ft_queue_head);
if (head->status == error ||
head->status == verifying) {
/* no data or overrun error */
head->status = waiting;
}
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 (verify_done) {
TRACE_EXIT 0;
}
/* Now at least one buffer is idle!
* Restart runner & tape if needed.
*/
/* We could optimize the following a little bit. We know that
* the bad sector map is empty.
*/
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);
ftape_calc_next_cluster(head);
if (ft_runner_status == idle) {
result = ftape_start_tape(segment_id,
head->sector_offset);
switch(result) {
case 0:
break;
case -ETIME:
case -EINTR:
TRACE_ABORT(result, ft_t_err, "Error: "
"segment %d unreachable",
segment_id);
break;
default:
*bsm = EMPTY_SEGMENT;
TRACE_EXIT 0;
break;
}
}
head->status = verifying;
fdc_setup_read_write(head, FDC_VERIFY);
}
}
/* not reached */
TRACE_EXIT -EIO;
}