Remove long-unmaintained ftape driver subsystem.

It's bitrotten, long unmaintained, long hidden under BROKEN_ON_SMP,
etc.  As scheduled in feature-removal-schedule.txt, and ack'd several
times on lkml.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 0 insertions, 1170 deletions

diff --git a/drivers/char/ftape/lowlevel/fdc-isr.c b/drivers/char/ftape/lowlevel/fdc-isr.c
deleted file mode 100644
index ad2bc733ae1b..000000000000
--- a/drivers/char/ftape/lowlevel/fdc-isr.c
+++ /dev/null
@@ -1,1170 +0,0 @@
-/*
- *      Copyright (C) 1994-1996 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/fdc-isr.c,v $
- * $Revision: 1.9 $
- * $Date: 1997/10/17 23:01:53 $
- *
- *      This file contains the interrupt service routine and
- *      associated code for the QIC-40/80/3010/3020 floppy-tape driver
- *      "ftape" for Linux.
- */
-
-#include <asm/io.h>
-#include <asm/dma.h>
-
-#define volatile		/* */
-
-#include <linux/ftape.h>
-#include <linux/qic117.h>
-#include "../lowlevel/ftape-tracing.h"
-#include "../lowlevel/fdc-isr.h"
-#include "../lowlevel/fdc-io.h"
-#include "../lowlevel/ftape-ctl.h"
-#include "../lowlevel/ftape-rw.h"
-#include "../lowlevel/ftape-io.h"
-#include "../lowlevel/ftape-calibr.h"
-#include "../lowlevel/ftape-bsm.h"
-
-/*      Global vars.
- */
-volatile int ft_expected_stray_interrupts;
-volatile int ft_interrupt_seen;
-volatile int ft_seek_completed;
-volatile int ft_hide_interrupt;
-/*      Local vars.
- */
-typedef enum {
-	no_error = 0, id_am_error = 0x01, id_crc_error = 0x02,
-	data_am_error = 0x04, data_crc_error = 0x08,
-	no_data_error = 0x10, overrun_error = 0x20,
-} error_cause;
-static int stop_read_ahead;
-
-
-static void print_error_cause(int cause)
-{
-	TRACE_FUN(ft_t_any);
-
-	switch (cause) {
-	case no_data_error:
-		TRACE(ft_t_noise, "no data error");
-		break;
-	case id_am_error:
-		TRACE(ft_t_noise, "id am error");
-		break;
-	case id_crc_error:
-		TRACE(ft_t_noise, "id crc error");
-		break;
-	case data_am_error:
-		TRACE(ft_t_noise, "data am error");
-		break;
-	case data_crc_error:
-		TRACE(ft_t_noise, "data crc error");
-		break;
-	case overrun_error:
-		TRACE(ft_t_noise, "overrun error");
-		break;
-	default:;
-	}
-	TRACE_EXIT;
-}
-
-static char *fdc_mode_txt(fdc_mode_enum mode)
-{
-	switch (mode) {
-	case fdc_idle:
-		return "fdc_idle";
-	case fdc_reading_data:
-		return "fdc_reading_data";
-	case fdc_seeking:
-		return "fdc_seeking";
-	case fdc_writing_data:
-		return "fdc_writing_data";
-	case fdc_reading_id:
-		return "fdc_reading_id";
-	case fdc_recalibrating:
-		return "fdc_recalibrating";
-	case fdc_formatting:
-		return "fdc_formatting";
-	case fdc_verifying:
-		return "fdc_verifying";
-	default:
-		return "unknown";
-	}
-}
-
-static inline error_cause decode_irq_cause(fdc_mode_enum mode, __u8 st[])
-{
-	error_cause cause = no_error;
-	TRACE_FUN(ft_t_any);
-
-	/*  Valid st[], decode cause of interrupt.
-	 */
-	switch (st[0] & ST0_INT_MASK) {
-	case FDC_INT_NORMAL:
-		TRACE(ft_t_fdc_dma,"normal completion: %s",fdc_mode_txt(mode));
-		break;
-	case FDC_INT_ABNORMAL:
-		TRACE(ft_t_flow, "abnormal completion %s", fdc_mode_txt(mode));
-		TRACE(ft_t_fdc_dma, "ST0: 0x%02x, ST1: 0x%02x, ST2: 0x%02x",
-		      st[0], st[1], st[2]);
-		TRACE(ft_t_fdc_dma,
-		      "C: 0x%02x, H: 0x%02x, R: 0x%02x, N: 0x%02x",
-		      st[3], st[4], st[5], st[6]);
-		if (st[1] & 0x01) {
-			if (st[2] & 0x01) {
-				cause = data_am_error;
-			} else {
-				cause = id_am_error;
-			}
-		} else if (st[1] & 0x20) {
-			if (st[2] & 0x20) {
-				cause = data_crc_error;
-			} else {
-				cause = id_crc_error;
-			}
-		} else if (st[1] & 0x04) {
-			cause = no_data_error;
-		} else if (st[1] & 0x10) {
-			cause = overrun_error;
-		}
-		print_error_cause(cause);
-		break;
-	case FDC_INT_INVALID:
-		TRACE(ft_t_flow, "invalid completion %s", fdc_mode_txt(mode));
-		break;
-	case FDC_INT_READYCH:
-		if (st[0] & ST0_SEEK_END) {
-			TRACE(ft_t_flow, "drive poll completed");
-		} else {
-			TRACE(ft_t_flow, "ready change %s",fdc_mode_txt(mode));
-		}
-		break;
-	default:
-		break;
-	}
-	TRACE_EXIT cause;
-}
-
-static void update_history(error_cause cause)
-{
-	switch (cause) {
-	case id_am_error:
-		ft_history.id_am_errors++;
-		break;
-	case id_crc_error:
-		ft_history.id_crc_errors++;
-		break;
-	case data_am_error:
-		ft_history.data_am_errors++;
-		break;
-	case data_crc_error:
-		ft_history.data_crc_errors++;
-		break;
-	case overrun_error:
-		ft_history.overrun_errors++;
-		break;
-	case no_data_error:
-		ft_history.no_data_errors++;
-		break;
-	default:;
-	}
-}
-
-static void skip_bad_sector(buffer_struct * buff)
-{
-	TRACE_FUN(ft_t_any);
-
-	/*  Mark sector as soft error and skip it
-	 */
-	if (buff->remaining > 0) {
-		++buff->sector_offset;
-		++buff->data_offset;
-		--buff->remaining;
-		buff->ptr += FT_SECTOR_SIZE;
-		buff->bad_sector_map >>= 1;
-	} else {
-		/*  Hey, what is this????????????? C code: if we shift 
-		 *  more than 31 bits, we get no shift. That's bad!!!!!!
-		 */
-		++buff->sector_offset;	/* hack for error maps */
-		TRACE(ft_t_warn, "skipping last sector in segment");
-	}
-	TRACE_EXIT;
-}
-
-static void update_error_maps(buffer_struct * buff, unsigned int error_offset)
-{
-	int hard = 0;
-	TRACE_FUN(ft_t_any);
-
-	if (buff->retry < FT_SOFT_RETRIES) {
-		buff->soft_error_map |= (1 << error_offset);
-	} else {
-		buff->hard_error_map |= (1 << error_offset);
-		buff->soft_error_map &= ~buff->hard_error_map;
-		buff->retry = -1;  /* will be set to 0 in setup_segment */
-		hard = 1;
-	}
-	TRACE(ft_t_noise, "sector %d : %s error\n"
-	      KERN_INFO "hard map: 0x%08lx\n"
-	      KERN_INFO "soft map: 0x%08lx",
-	      FT_SECTOR(error_offset), hard ? "hard" : "soft",
-	      (long) buff->hard_error_map, (long) buff->soft_error_map);
-	TRACE_EXIT;
-}
-
-static void print_progress(buffer_struct *buff, error_cause cause)
-{
-	TRACE_FUN(ft_t_any);
-
-	switch (cause) {
-	case no_error: 
-		TRACE(ft_t_flow,"%d Sector(s) transferred", buff->sector_count);
-		break;
-	case no_data_error:
-		TRACE(ft_t_flow, "Sector %d not found",
-		      FT_SECTOR(buff->sector_offset));
-		break;
-	case overrun_error:
-		/*  got an overrun error on the first byte, must be a
-		 *  hardware problem
-		 */
-		TRACE(ft_t_bug,
-		      "Unexpected error: failing DMA or FDC controller ?");
-		break;
-	case data_crc_error:
-		TRACE(ft_t_flow, "Error in sector %d",
-		      FT_SECTOR(buff->sector_offset - 1));
-		break;
-	case id_crc_error:
-	case id_am_error:
-	case data_am_error:
-		TRACE(ft_t_flow, "Error in sector %d",
-		      FT_SECTOR(buff->sector_offset));
-		break;
-	default:
-		TRACE(ft_t_flow, "Unexpected error at sector %d",
-		      FT_SECTOR(buff->sector_offset));
-		break;
-	}
-	TRACE_EXIT;
-}
-
-/*
- *  Error cause:   Amount xferred:  Action:
- *
- *  id_am_error         0           mark bad and skip
- *  id_crc_error        0           mark bad and skip
- *  data_am_error       0           mark bad and skip
- *  data_crc_error    % 1024        mark bad and skip
- *  no_data_error       0           retry on write
- *                                  mark bad and skip on read
- *  overrun_error  [ 0..all-1 ]     mark bad and skip
- *  no_error           all          continue
- */
-
-/*  the arg `sector' is returned by the fdc and tells us at which sector we
- *  are positioned at (relative to starting sector of segment)
- */
-static void determine_verify_progress(buffer_struct *buff,
-				      error_cause cause,
-				      __u8 sector)
-{
-	TRACE_FUN(ft_t_any);
-
-	if (cause == no_error && sector == 1) {
-		buff->sector_offset = FT_SECTORS_PER_SEGMENT;
-		buff->remaining     = 0;
-		if (TRACE_LEVEL >= ft_t_flow) {
-			print_progress(buff, cause);
-		}
-	} else {
-		buff->sector_offset = sector - buff->sect;
-		buff->remaining = FT_SECTORS_PER_SEGMENT - buff->sector_offset;
-		TRACE(ft_t_noise, "%ssector offset: 0x%04x", 
-		      (cause == no_error) ? "unexpected " : "",
-		      buff->sector_offset);
-		switch (cause) {
-		case overrun_error:
-			break;
-#if 0
-		case no_data_error:
-			buff->retry = FT_SOFT_RETRIES;
-			if (buff->hard_error_map    &&
-			    buff->sector_offset > 1 &&
-			    (buff->hard_error_map & 
-			     (1 << (buff->sector_offset-2)))) {
-				buff->retry --;
-			}
-			break;
-#endif
-		default:
-			buff->retry = FT_SOFT_RETRIES;
-			break;
-		}
-		if (TRACE_LEVEL >= ft_t_flow) {
-			print_progress(buff, cause);
-		}
-		/*  Sector_offset points to the problem area Now adjust
-		 *  sector_offset so it always points one past he failing
-		 *  sector. I.e. skip the bad sector.
-		 */
-		++buff->sector_offset;
-		--buff->remaining;
-		update_error_maps(buff, buff->sector_offset - 1);
-	}
-	TRACE_EXIT;
-}
-
-static void determine_progress(buffer_struct *buff,
-			       error_cause cause,
-			       __u8 sector)
-{
-	unsigned int dma_residue;
-	TRACE_FUN(ft_t_any);
-
-	/*  Using less preferred order of disable_dma and
-	 *  get_dma_residue because this seems to fail on at least one
-	 *  system if reversed!
-	 */
-	dma_residue = get_dma_residue(fdc.dma);
-	disable_dma(fdc.dma);
-	if (cause != no_error || dma_residue != 0) {
-		TRACE(ft_t_noise, "%sDMA residue: 0x%04x", 
-		      (cause == no_error) ? "unexpected " : "",
-		      dma_residue);
-		/* adjust to actual value: */
-		if (dma_residue == 0) {
-			/* this happens sometimes with overrun errors.
-			 * I don't know whether we could ignore the
-			 * overrun error. Play save.
-			 */
-			buff->sector_count --;
-		} else {
-			buff->sector_count -= ((dma_residue + 
-						(FT_SECTOR_SIZE - 1)) /
-					       FT_SECTOR_SIZE);
-		}
-	}
-	/*  Update var's influenced by the DMA operation.
-	 */
-	if (buff->sector_count > 0) {
-		buff->sector_offset   += buff->sector_count;
-		buff->data_offset     += buff->sector_count;
-		buff->ptr             += (buff->sector_count *
-					  FT_SECTOR_SIZE);
-		buff->remaining       -= buff->sector_count;
-		buff->bad_sector_map >>= buff->sector_count;
-	}
-	if (TRACE_LEVEL >= ft_t_flow) {
-		print_progress(buff, cause);
-	}
-	if (cause != no_error) {
-		if (buff->remaining == 0) {
-			TRACE(ft_t_warn, "foo?\n"
-			      KERN_INFO "count : %d\n"
-			      KERN_INFO "offset: %d\n"
-			      KERN_INFO "soft  : %08x\n"
-			      KERN_INFO "hard  : %08x",
-			      buff->sector_count,
-			      buff->sector_offset,
-			      buff->soft_error_map,
-			      buff->hard_error_map);
-		}
-		/*  Sector_offset points to the problem area, except if we got
-		 *  a data_crc_error. In that case it points one past the
-		 *  failing sector.
-		 *
-		 *  Now adjust sector_offset so it always points one past he
-		 *  failing sector. I.e. skip the bad sector.  
-		 */
-		if (cause != data_crc_error) {
-			skip_bad_sector(buff);
-		}
-		update_error_maps(buff, buff->sector_offset - 1);
-	}
-	TRACE_EXIT;
-}
-
-static int calc_steps(int cmd)
-{
-	if (ftape_current_cylinder > cmd) {
-		return ftape_current_cylinder - cmd;
-	} else {
-		return ftape_current_cylinder + cmd;
-	}
-}
-
-static void pause_tape(int retry, int mode)
-{
-	int result;
-	__u8 out[3] = {FDC_SEEK, ft_drive_sel, 0};
-	TRACE_FUN(ft_t_any);
-
-	/*  We'll use a raw seek command to get the tape to rewind and
-	 *  stop for a retry.
-	 */
-	++ft_history.rewinds;
-	if (qic117_cmds[ftape_current_command].non_intr) {
-		TRACE(ft_t_warn, "motion command may be issued too soon");
-	}
-	if (retry && (mode == fdc_reading_data ||
-		      mode == fdc_reading_id   ||
-		      mode == fdc_verifying)) {
-		ftape_current_command = QIC_MICRO_STEP_PAUSE;
-		ftape_might_be_off_track = 1;
-	} else {
-		ftape_current_command = QIC_PAUSE;
-	}
-	out[2] = calc_steps(ftape_current_command);
-	result = fdc_command(out, 3); /* issue QIC_117 command */
-	ftape_current_cylinder = out[ 2];
-	if (result < 0) {
-		TRACE(ft_t_noise, "qic-pause failed, status = %d", result);
-	} else {
-		ft_location.known  = 0;
-		ft_runner_status   = idle;
-		ft_hide_interrupt     = 1;
-		ftape_tape_running = 0;
-	}
-	TRACE_EXIT;
-}
-
-static void continue_xfer(buffer_struct *buff,
-			  fdc_mode_enum mode, 
-			  unsigned int skip)
-{
-	int write = 0;
- 	TRACE_FUN(ft_t_any);
-
-	if (mode == fdc_writing_data || mode == fdc_deleting) {
-		write = 1;
-	}
-	/*  This part can be removed if it never happens
-	 */
-	if (skip > 0 &&
-	    (ft_runner_status != running ||
-	     (write && (buff->status != writing)) ||
-	     (!write && (buff->status != reading && 
-			 buff->status != verifying)))) {
-		TRACE(ft_t_err, "unexpected runner/buffer state %d/%d",
-		      ft_runner_status, buff->status);
-		buff->status = error;
-		/* finish this buffer: */
-		(void)ftape_next_buffer(ft_queue_head);
-		ft_runner_status = aborting;
-		fdc_mode         = fdc_idle;
-	} else if (buff->remaining > 0 && ftape_calc_next_cluster(buff) > 0) {
-		/*  still sectors left in current segment, continue
-		 *  with this segment
-		 */
-		if (fdc_setup_read_write(buff, mode) < 0) {
-			/* failed, abort operation
-			 */
-			buff->bytes = buff->ptr - buff->address;
-			buff->status = error;
-			/* finish this buffer: */
-			(void)ftape_next_buffer(ft_queue_head);
-			ft_runner_status = aborting;
-			fdc_mode         = fdc_idle;
-		}
-	} else {
-		/* current segment completed
-		 */
-		unsigned int last_segment = buff->segment_id;
-		int eot = ((last_segment + 1) % ft_segments_per_track) == 0;
-		unsigned int next = buff->next_segment;	/* 0 means stop ! */
-
-		buff->bytes = buff->ptr - buff->address;
-		buff->status = done;
-		buff = ftape_next_buffer(ft_queue_head);
-		if (eot) {
-			/*  finished last segment on current track,
-			 *  can't continue
-			 */
-			ft_runner_status = logical_eot;
-			fdc_mode         = fdc_idle;
-			TRACE_EXIT;
-		}
-		if (next <= 0) {
-			/*  don't continue with next segment
-			 */
-			TRACE(ft_t_noise, "no %s allowed, stopping tape",
-			      (write) ? "write next" : "read ahead");
-			pause_tape(0, mode);
-			ft_runner_status = idle;  /*  not quite true until
-						   *  next irq 
-						   */
-			TRACE_EXIT;
-		}
-		/*  continue with next segment
-		 */
-		if (buff->status != waiting) {
-			TRACE(ft_t_noise, "all input buffers %s, pausing tape",
-			      (write) ? "empty" : "full");
-			pause_tape(0, mode);
-			ft_runner_status = idle;  /*  not quite true until
-						   *  next irq 
-						   */
-			TRACE_EXIT;
-		}
-		if (write && next != buff->segment_id) {
-			TRACE(ft_t_noise, 
-			      "segments out of order, aborting write");
-			ft_runner_status = do_abort;
-			fdc_mode         = fdc_idle;
-			TRACE_EXIT;
-		}
-		ftape_setup_new_segment(buff, next, 0);
-		if (stop_read_ahead) {
-			buff->next_segment = 0;
-			stop_read_ahead = 0;
-		}
-		if (ftape_calc_next_cluster(buff) == 0 ||
-		    fdc_setup_read_write(buff, mode) != 0) {
-			TRACE(ft_t_err, "couldn't start %s-ahead",
-			      write ? "write" : "read");
-			ft_runner_status = do_abort;
-			fdc_mode         = fdc_idle;
-		} else {
-			/* keep on going */
-			switch (ft_driver_state) {
-			case   reading: buff->status = reading;   break;
-			case verifying: buff->status = verifying; break;
-			case   writing: buff->status = writing;   break;
-			case  deleting: buff->status = deleting;  break;
-			default:
-				TRACE(ft_t_err, 
-		      "BUG: ft_driver_state %d should be one out of "
-		      "{reading, writing, verifying, deleting}",
-				      ft_driver_state);
-				buff->status = write ? writing : reading;
-				break;
-			}
-		}
-	}
-	TRACE_EXIT;
-}
-
-static void retry_sector(buffer_struct *buff, 
-			 int mode,
-			 unsigned int skip)
-{
-	TRACE_FUN(ft_t_any);
-
-	TRACE(ft_t_noise, "%s error, will retry",
-	      (mode == fdc_writing_data || mode == fdc_deleting) ? "write" : "read");
-	pause_tape(1, mode);
-	ft_runner_status = aborting;
-	buff->status     = error;
-	buff->skip       = skip;
-	TRACE_EXIT;
-}
-
-static unsigned int find_resume_point(buffer_struct *buff)
-{
-	int i = 0;
-	SectorMap mask;
-	SectorMap map;
-	TRACE_FUN(ft_t_any);
-
-	/*  This function is to be called after all variables have been
-	 *  updated to point past the failing sector.
-	 *  If there are any soft errors before the failing sector,
-	 *  find the first soft error and return the sector offset.
-	 *  Otherwise find the last hard error.
-	 *  Note: there should always be at least one hard or soft error !
-	 */
-	if (buff->sector_offset < 1 || buff->sector_offset > 32) {
-		TRACE(ft_t_bug, "BUG: sector_offset = %d",
-		      buff->sector_offset);
-		TRACE_EXIT 0;
-	}
-	if (buff->sector_offset >= 32) { /* C-limitation on shift ! */
-		mask = 0xffffffff;
-	} else {
-		mask = (1 << buff->sector_offset) - 1;
-	}
-	map = buff->soft_error_map & mask;
-	if (map) {
-		while ((map & (1 << i)) == 0) {
-			++i;
-		}
-		TRACE(ft_t_noise, "at sector %d", FT_SECTOR(i));
-	} else {
-		map = buff->hard_error_map & mask;
-		i = buff->sector_offset - 1;
-		if (map) {
-			while ((map & (1 << i)) == 0) {
-				--i;
-			}
-			TRACE(ft_t_noise, "after sector %d", FT_SECTOR(i));
-			++i; /* first sector after last hard error */
-		} else {
-			TRACE(ft_t_bug, "BUG: no soft or hard errors");
-		}
-	}
-	TRACE_EXIT i;
-}
-
-/*  check possible dma residue when formatting, update position record in
- *  buffer struct. This is, of course, modelled after determine_progress(), but
- *  we don't need to set up for retries because the format process cannot be
- *  interrupted (except at the end of the tape track).
- */
-static int determine_fmt_progress(buffer_struct *buff, error_cause cause)
-{
-	unsigned int dma_residue;
-	TRACE_FUN(ft_t_any);
-
-	/*  Using less preferred order of disable_dma and
-	 *  get_dma_residue because this seems to fail on at least one
-	 *  system if reversed!
-	 */
-	dma_residue = get_dma_residue(fdc.dma);
-	disable_dma(fdc.dma);
-	if (cause != no_error || dma_residue != 0) {
-		TRACE(ft_t_info, "DMA residue = 0x%04x", dma_residue);
-		fdc_mode = fdc_idle;
-		switch(cause) {
-		case no_error:
-			ft_runner_status = aborting;
-			buff->status = idle;
-			break;
-		case overrun_error:
-			/*  got an overrun error on the first byte, must be a
-			 *  hardware problem 
-			 */
-			TRACE(ft_t_bug, 
-			      "Unexpected error: failing DMA controller ?");
-			ft_runner_status = do_abort;
-			buff->status = error;
-			break;
-		default:
-			TRACE(ft_t_noise, "Unexpected error at segment %d",
-			      buff->segment_id);
-			ft_runner_status = do_abort;
-			buff->status = error;
-			break;
-		}
-		TRACE_EXIT -EIO; /* can only retry entire track in format mode
-				  */
-	}
-	/*  Update var's influenced by the DMA operation.
-	 */
-	buff->ptr             += FT_SECTORS_PER_SEGMENT * 4;
-	buff->bytes           -= FT_SECTORS_PER_SEGMENT * 4;
-	buff->remaining       -= FT_SECTORS_PER_SEGMENT;
-	buff->segment_id ++; /* done with segment */
-	TRACE_EXIT 0;
-}
-
-/*
- *  Continue formatting, switch buffers if there is no data left in
- *  current buffer. This is, of course, modelled after
- *  continue_xfer(), but we don't need to set up for retries because
- *  the format process cannot be interrupted (except at the end of the
- *  tape track).
- */
-static void continue_formatting(buffer_struct *buff)
-{
-	TRACE_FUN(ft_t_any);
-
-	if (buff->remaining <= 0) { /*  no space left in dma buffer */
-		unsigned int next = buff->next_segment; 
-
-		if (next == 0) { /* end of tape track */
-			buff->status     = done;
-			ft_runner_status = logical_eot;
-			fdc_mode         = fdc_idle;
-			TRACE(ft_t_noise, "Done formatting track %d",
-			      ft_location.track);
-			TRACE_EXIT;
-		}
-		/*
-		 *  switch to next buffer!
-		 */
-		buff->status   = done;
-		buff = ftape_next_buffer(ft_queue_head);
-
-		if (buff->status != waiting  || next != buff->segment_id) {
-			goto format_setup_error;
-		}
-	}
-	if (fdc_setup_formatting(buff) < 0) {
-		goto format_setup_error;
-	}
-	buff->status = formatting;
-	TRACE(ft_t_fdc_dma, "Formatting segment %d on track %d",
-	      buff->segment_id, ft_location.track);
-	TRACE_EXIT;
- format_setup_error:
-	ft_runner_status = do_abort;
-	fdc_mode         = fdc_idle;
-	buff->status     = error;
-	TRACE(ft_t_err, "Error setting up for segment %d on track %d",
-	      buff->segment_id, ft_location.track);
-	TRACE_EXIT;
-
-}
-
-/*  this handles writing, read id, reading and formatting
- */
-static void handle_fdc_busy(buffer_struct *buff)
-{
-	static int no_data_error_count;
-	int retry = 0;
-	error_cause cause;
-	__u8 in[7];
-	int skip;
-	fdc_mode_enum fmode = fdc_mode;
-	TRACE_FUN(ft_t_any);
-
-	if (fdc_result(in, 7) < 0) { /* better get it fast ! */
-		TRACE(ft_t_err, 
-		      "Probably fatal error during FDC Result Phase\n"
-		      KERN_INFO
-		      "drive may hang until (power on) reset :-(");
-		/*  what to do next ????
-		 */
-		TRACE_EXIT;
-	}
-	cause = decode_irq_cause(fdc_mode, in);
-#ifdef TESTING
-	{ int i;
-	for (i = 0; i < (int)ft_nr_buffers; ++i)
-		TRACE(ft_t_any, "buffer[%d] status: %d, segment_id: %d",
-		      i, ft_buffer[i]->status, ft_buffer[i]->segment_id);
-	}
-#endif
-	if (fmode == fdc_reading_data && ft_driver_state == verifying) {
-		fmode = fdc_verifying;
-	}
-	switch (fmode) {
-	case fdc_verifying:
-		if (ft_runner_status == aborting ||
-		    ft_runner_status == do_abort) {
-			TRACE(ft_t_noise,"aborting %s",fdc_mode_txt(fdc_mode));
-			break;
-		}
-		if (buff->retry > 0) {
-			TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
-		}
-		switch (cause) {
-		case no_error:
-			no_data_error_count = 0;
-			determine_verify_progress(buff, cause, in[5]);
-			if (in[2] & 0x40) {
-				/*  This should not happen when verifying
-				 */
-				TRACE(ft_t_warn,
-				      "deleted data in segment %d/%d",
-				      buff->segment_id,
-				      FT_SECTOR(buff->sector_offset - 1));
-				buff->remaining = 0; /* abort transfer */
-				buff->hard_error_map = EMPTY_SEGMENT;
-				skip = 1;
-			} else {
-				skip = 0;
-			}
-			continue_xfer(buff, fdc_mode, skip);
-			break;
-		case no_data_error:
-			no_data_error_count ++;
-		case overrun_error:
-			retry ++;
-		case id_am_error:
-		case id_crc_error:
-		case data_am_error:
-		case data_crc_error:
-			determine_verify_progress(buff, cause, in[5]); 
-			if (cause == no_data_error) {
-				if (no_data_error_count >= 2) {
-					TRACE(ft_t_warn,
-					      "retrying because of successive "
-					      "no data errors");
-					no_data_error_count = 0;
-				} else {
-					retry --;
-				}
-			} else {
-				no_data_error_count = 0;
-			}
-			if (retry) {
-				skip = find_resume_point(buff);
-			} else {
-				skip = buff->sector_offset;
-			}
-			if (retry && skip < 32) {
-				retry_sector(buff, fdc_mode, skip);
-			} else {
-				continue_xfer(buff, fdc_mode, skip);
-			}
-			update_history(cause);
-			break;
-		default:
-			/*  Don't know why this could happen 
-			 *  but find out.
-			 */
-			determine_verify_progress(buff, cause, in[5]);
-			retry_sector(buff, fdc_mode, 0);
-			TRACE(ft_t_err, "Error: unexpected error");
-			break;
-		}
-		break;
-	case fdc_reading_data:
-#ifdef TESTING
-		/* I'm sorry, but: NOBODY ever used this trace
-		 * messages for ages. I guess that Bas was the last person
-		 * that ever really used this (thank you, between the lines)
-		 */
-		if (cause == no_error) {
-			TRACE(ft_t_flow,"reading segment %d",buff->segment_id);
-		} else {
-			TRACE(ft_t_noise, "error reading segment %d",
-			      buff->segment_id);
-			TRACE(ft_t_noise, "\n"
-			      KERN_INFO
-			     "IRQ:C: 0x%02x, H: 0x%02x, R: 0x%02x, N: 0x%02x\n"
-			      KERN_INFO
-			      "BUF:C: 0x%02x, H: 0x%02x, R: 0x%02x",
-			      in[3], in[4], in[5], in[6],
-			      buff->cyl, buff->head, buff->sect);
-		}
-#endif
-		if (ft_runner_status == aborting ||
-		    ft_runner_status == do_abort) {
-			TRACE(ft_t_noise,"aborting %s",fdc_mode_txt(fdc_mode));
-			break;
-		}
-		if (buff->bad_sector_map == FAKE_SEGMENT) {
-			/* This condition occurs when reading a `fake'
-			 * sector that's not accessible. Doesn't
-			 * really matter as we would have ignored it
-			 * anyway !
-			 *
-			 * Chance is that we're past the next segment
-			 * now, so the next operation may fail and
-			 * result in a retry.  
-			 */
-			buff->remaining = 0;	/* skip failing sector */
-			/* buff->ptr       = buff->address; */
-			/* fake success: */
-			continue_xfer(buff, fdc_mode, 1);
-			/*  trace calls are expensive: place them AFTER
-			 *  the real stuff has been done.
-			 *  
-			 */
-			TRACE(ft_t_noise, "skipping empty segment %d (read), size? %d",
-			      buff->segment_id, buff->ptr - buff->address);
-			TRACE_EXIT;
-		}
-		if (buff->retry > 0) {
-			TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
-		}
-		switch (cause) {
-		case no_error:
-			determine_progress(buff, cause, in[5]);
-			if (in[2] & 0x40) {
-				/*  Handle deleted data in header segments.
-				 *  Skip segment and force read-ahead.
-				 */
-				TRACE(ft_t_warn,
-				      "deleted data in segment %d/%d",
-				      buff->segment_id,
-				      FT_SECTOR(buff->sector_offset - 1));
-				buff->deleted = 1;
-				buff->remaining = 0;/*abort transfer */
-				buff->soft_error_map |=
-						(-1L << buff->sector_offset);
-				if (buff->segment_id == 0) {
-					/* stop on next segment */
-					stop_read_ahead = 1;
-				}
-				/* force read-ahead: */
-				buff->next_segment = 
-					buff->segment_id + 1;
-				skip = (FT_SECTORS_PER_SEGMENT - 
-					buff->sector_offset);
-			} else {
-				skip = 0;
-			}
-			continue_xfer(buff, fdc_mode, skip);
-			break;
-		case no_data_error:
-			/* Tape started too far ahead of or behind the
-			 * right sector.  This may also happen in the
-			 * middle of a segment !
-			 *
-			 * Handle no-data as soft error. If next
-			 * sector fails too, a retry (with needed
-			 * reposition) will follow.
-			 */
-			retry ++;
-		case id_am_error:
-		case id_crc_error:
-		case data_am_error:
-		case data_crc_error:
-		case overrun_error:
-			retry += (buff->soft_error_map != 0 ||
-				  buff->hard_error_map != 0);
-			determine_progress(buff, cause, in[5]); 
-#if 1 || defined(TESTING)
-			if (cause == overrun_error) retry ++;
-#endif
-			if (retry) {
-				skip = find_resume_point(buff);
-			} else {
-				skip = buff->sector_offset;
-			}
-			/*  Try to resume with next sector on single
-			 *  errors (let ecc correct it), but retry on
-			 *  no_data (we'll be past the target when we
-			 *  get here so we cannot retry) or on
-			 *  multiple errors (reduce chance on ecc
-			 *  failure).
-			 */
-			/*  cH: 23/02/97: if the last sector in the 
-			 *  segment was a hard error, then there is 
-			 *  no sense in a retry. This occasion seldom
-			 *  occurs but ... @:³²¸`@%&§$
-			 */
-			if (retry && skip < 32) {
-				retry_sector(buff, fdc_mode, skip);
-			} else {
-				continue_xfer(buff, fdc_mode, skip);
-			}
-			update_history(cause);
-			break;
-		default:
-			/*  Don't know why this could happen 
-			 *  but find out.
-			 */
-			determine_progress(buff, cause, in[5]);
-			retry_sector(buff, fdc_mode, 0);
-			TRACE(ft_t_err, "Error: unexpected error");
-			break;
-		}
-		break;
-	case fdc_reading_id:
-		if (cause == no_error) {
-			fdc_cyl = in[3];
-			fdc_head = in[4];
-			fdc_sect = in[5];
-			TRACE(ft_t_fdc_dma,
-			      "id read: C: 0x%02x, H: 0x%02x, R: 0x%02x",
-			      fdc_cyl, fdc_head, fdc_sect);
-		} else {	/* no valid information, use invalid sector */
-			fdc_cyl = fdc_head = fdc_sect = 0;
-			TRACE(ft_t_flow, "Didn't find valid sector Id");
-		}
-		fdc_mode = fdc_idle;
-		break;
-	case fdc_deleting:
-	case fdc_writing_data:
-#ifdef TESTING
-		if (cause == no_error) {
-			TRACE(ft_t_flow, "writing segment %d", buff->segment_id);
-		} else {
-			TRACE(ft_t_noise, "error writing segment %d",
-			      buff->segment_id);
-		}
-#endif
-		if (ft_runner_status == aborting ||
-		    ft_runner_status == do_abort) {
-			TRACE(ft_t_flow, "aborting %s",fdc_mode_txt(fdc_mode));
-			break;
-		}
-		if (buff->retry > 0) {
-			TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
-		}
-		if (buff->bad_sector_map == FAKE_SEGMENT) {
-			/* This condition occurs when trying to write to a
-			 * `fake' sector that's not accessible. Doesn't really
-			 * matter as it isn't used anyway ! Might be located
-			 * at wrong segment, then we'll fail on the next
-			 * segment.
-			 */
-			TRACE(ft_t_noise, "skipping empty segment (write)");
-			buff->remaining = 0;	/* skip failing sector */
-			/* fake success: */
-			continue_xfer(buff, fdc_mode, 1);
-			break;
-		}
-		switch (cause) {
-		case no_error:
-			determine_progress(buff, cause, in[5]);
-			continue_xfer(buff, fdc_mode, 0);
-			break;
-		case no_data_error:
-		case id_am_error:
-		case id_crc_error:
-		case data_am_error:
-		case overrun_error:
-			update_history(cause);
-			determine_progress(buff, cause, in[5]);
-			skip = find_resume_point(buff);
-			retry_sector(buff, fdc_mode, skip);
-			break;
-		default:
-			if (in[1] & 0x02) {
-				TRACE(ft_t_err, "media not writable");
-			} else {
-				TRACE(ft_t_bug, "unforeseen write error");
-			}
-			fdc_mode = fdc_idle;
-			break;
-		}
-		break; /* fdc_deleting || fdc_writing_data */
-	case fdc_formatting:
-		/*  The interrupt comes after formatting a segment. We then
-		 *  have to set up QUICKLY for the next segment. But
-		 *  afterwards, there is plenty of time.
-		 */
-		switch (cause) {
-		case no_error:
-			/*  would like to keep most of the formatting stuff
-			 *  outside the isr code, but timing is too critical
-			 */
-			if (determine_fmt_progress(buff, cause) >= 0) {
-				continue_formatting(buff);
-			}
-			break;
-		case no_data_error:
-		case id_am_error:
-		case id_crc_error:
-		case data_am_error:
-		case overrun_error:
-		default:
-			determine_fmt_progress(buff, cause);
-			update_history(cause);
-			if (in[1] & 0x02) {
-				TRACE(ft_t_err, "media not writable");
-			} else {
-				TRACE(ft_t_bug, "unforeseen write error");
-			}
-			break;
-		} /* cause */
-		break;
-	default:
-		TRACE(ft_t_warn, "Warning: unexpected irq during: %s",
-		      fdc_mode_txt(fdc_mode));
-		fdc_mode = fdc_idle;
-		break;
-	}
-	TRACE_EXIT;
-}
-
-/*      FDC interrupt service routine.
- */
-void fdc_isr(void)
-{
-	static int isr_active;
-#ifdef TESTING
-	unsigned int t0 = ftape_timestamp();
-#endif
-	TRACE_FUN(ft_t_any);
-
- 	if (isr_active++) {
-		--isr_active;
-		TRACE(ft_t_bug, "BUG: nested interrupt, not good !");
-		*fdc.hook = fdc_isr; /*  hook our handler into the fdc
-				      *  code again 
-				      */
-		TRACE_EXIT;
-	}
-	sti();
-	if (inb_p(fdc.msr) & FDC_BUSY) {	/*  Entering Result Phase */
-		ft_hide_interrupt = 0;
-		handle_fdc_busy(ftape_get_buffer(ft_queue_head));
-		if (ft_runner_status == do_abort) {
-			/*      cease operation, remember tape position
-			 */
-			TRACE(ft_t_flow, "runner aborting");
-			ft_runner_status = aborting;
-			++ft_expected_stray_interrupts;
-		}
-	} else { /* !FDC_BUSY */
-		/*  clear interrupt, cause should be gotten by issuing
-		 *  a Sense Interrupt Status command.
-		 */
-		if (fdc_mode == fdc_recalibrating || fdc_mode == fdc_seeking) {
-			if (ft_hide_interrupt) {
-				int st0;
-				int pcn;
-
-				if (fdc_sense_interrupt_status(&st0, &pcn) < 0)
-					TRACE(ft_t_err,
-					      "sense interrupt status failed");
-				ftape_current_cylinder = pcn;
-				TRACE(ft_t_flow, "handled hidden interrupt");
-			}
-			ft_seek_completed = 1;
-			fdc_mode = fdc_idle;
-		} else if (!waitqueue_active(&ftape_wait_intr)) {
-			if (ft_expected_stray_interrupts == 0) {
-				TRACE(ft_t_warn, "unexpected stray interrupt");
-			} else {
-				TRACE(ft_t_flow, "expected stray interrupt");
-				--ft_expected_stray_interrupts;
-			}
-		} else {
-			if (fdc_mode == fdc_reading_data ||
-			    fdc_mode == fdc_verifying    ||
-			    fdc_mode == fdc_writing_data ||
-			    fdc_mode == fdc_deleting     ||
-			    fdc_mode == fdc_formatting   ||
-			    fdc_mode == fdc_reading_id) {
-				if (inb_p(fdc.msr) & FDC_BUSY) {
-					TRACE(ft_t_bug,
-					"***** FDC failure, busy too late");
-				} else {
-					TRACE(ft_t_bug,
-					      "***** FDC failure, no busy");
-				}
-			} else {
-				TRACE(ft_t_fdc_dma, "awaited stray interrupt");
-			}
-		}
-		ft_hide_interrupt = 0;
-	}
-	/*    Handle sleep code.
-	 */
-	if (!ft_hide_interrupt) {
-		ft_interrupt_seen ++;
-		if (waitqueue_active(&ftape_wait_intr)) {
-			wake_up_interruptible(&ftape_wait_intr);
-		}
-	} else {
-		TRACE(ft_t_flow, "hiding interrupt while %s", 
-		      waitqueue_active(&ftape_wait_intr) ? "waiting":"active");
-	}
-#ifdef TESTING
-	t0 = ftape_timediff(t0, ftape_timestamp());
-	if (t0 >= 1000) {
-		/* only tell us about long calls */
-		TRACE(ft_t_noise, "isr() duration: %5d usec", t0);
-	}
-#endif
-	*fdc.hook = fdc_isr;	/* hook our handler into the fdc code again */
-	--isr_active;
-	TRACE_EXIT;
-}