/*
   *  linux/drivers/block/floppy.c
   *
   *  Copyright (C) 1991, 1992  Linus Torvalds
   *  Copyright (C) 1993, 1994  Alain Knaff
   *  Copyright (C) 1998 Alan Cox
   */

  /*
   * 02.12.91 - Changed to static variables to indicate need for reset
   * and recalibrate. This makes some things easier (output_byte reset
   * checking etc), and means less interrupt jumping in case of errors,
   * so the code is hopefully easier to understand.
   */
  
  /*
   * This file is certainly a mess. I've tried my best to get it working,
   * but I don't like programming floppies, and I have only one anyway.
   * Urgel. I should check for more errors, and do more graceful error
   * recovery. Seems there are problems with several drives. I've tried to
   * correct them. No promises.
   */
  
  /*
   * As with hd.c, all routines within this file can (and will) be called
   * by interrupts, so extreme caution is needed. A hardware interrupt
   * handler may not sleep, or a kernel panic will happen. Thus I cannot
   * call "floppy-on" directly, but have to set a special timer interrupt
   * etc.
   */
  
  /*
   * 28.02.92 - made track-buffering routines, based on the routines written
   * by entropy@wintermute.wpi.edu (Lawrence Foard). Linus.
   */
  
  /*
   * Automatic floppy-detection and formatting written by Werner Almesberger
   * (almesber@nessie.cs.id.ethz.ch), who also corrected some problems with
   * the floppy-change signal detection.
   */
  
  /*
   * 1992/7/22 -- Hennus Bergman: Added better error reporting, fixed
   * FDC data overrun bug, added some preliminary stuff for vertical
   * recording support.
   *
   * 1992/9/17: Added DMA allocation & DMA functions. -- hhb.
   *
   * TODO: Errors are still not counted properly.
   */
  
  /* 1992/9/20
   * Modifications for ``Sector Shifting'' by Rob Hooft (hooft@chem.ruu.nl)
   * modeled after the freeware MS-DOS program fdformat/88 V1.8 by
   * Christoph H. Hochst\"atter.
   * I have fixed the shift values to the ones I always use. Maybe a new
   * ioctl() should be created to be able to modify them.
   * There is a bug in the driver that makes it impossible to format a
   * floppy as the first thing after bootup.
   */
  
  /*
   * 1993/4/29 -- Linus -- cleaned up the timer handling in the kernel, and
   * this helped the floppy driver as well. Much cleaner, and still seems to
   * work.
   */
  
  /* 1994/6/24 --bbroad-- added the floppy table entries and made
   * minor modifications to allow 2.88 floppies to be run.
   */
  
  /* 1994/7/13 -- Paul Vojta -- modified the probing code to allow three or more
   * disk types.
   */
  
  /*
   * 1994/8/8 -- Alain Knaff -- Switched to fdpatch driver: Support for bigger
   * format bug fixes, but unfortunately some new bugs too...
   */
  
  /* 1994/9/17 -- Koen Holtman -- added logging of physical floppy write
   * errors to allow safe writing by specialized programs.
   */
  
  /* 1995/4/24 -- Dan Fandrich -- added support for Commodore 1581 3.5" disks
   * by defining bit 1 of the "stretch" parameter to mean put sectors on the
   * opposite side of the disk, leaving the sector IDs alone (i.e. Commodore's
   * drives are "upside-down").
   */
  
  /*
   * 1995/8/26 -- Andreas Busse -- added Mips support.
   */
  
  /*
   * 1995/10/18 -- Ralf Baechle -- Portability cleanup; move machine dependent
   * features to asm/floppy.h.
   */
  
  /*

   * 1998/1/21 -- Richard Gooch <rgooch@atnf.csiro.au> -- devfs support
   */
  
  /*

   * 1998/05/07 -- Russell King -- More portability cleanups; moved definition of
   * interrupt and dma channel to asm/floppy.h. Cleaned up some formatting &
   * use of '0' for NULL.
   */
  
  /*
   * 1998/06/07 -- Alan Cox -- Merged the 2.0.34 fixes for resource allocation
   * failures.
   */
  
  /*
   * 1998/09/20 -- David Weinehall -- Added slow-down code for buggy PS/2-drives.
   */
  
  /*
   * 1999/08/13 -- Paul Slootman -- floppy stopped working on Alpha after 24
   * days, 6 hours, 32 minutes and 32 seconds (i.e. MAXINT jiffies; ints were
   * being used to store jiffies, which are unsigned longs).
   */
  
  /*
   * 2000/08/28 -- Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   * - get rid of check_region
   * - s/suser/capable/
   */
  
  /*
   * 2001/08/26 -- Paul Gortmaker - fix insmod oops on machines with no
   * floppy controller (lingering task on list after module is gone... boom.)
   */
  
  /*
   * 2002/02/07 -- Anton Altaparmakov - Fix io ports reservation to correct range
   * (0x3f2-0x3f5, 0x3f7). This fix is a bit of a hack but the proper fix
   * requires many non-obvious changes in arch dependent code.
   */
  
  /* 2003/07/28 -- Daniele Bellucci <bellucda@tiscali.it>.
   * Better audit of register_blkdev.
   */

  #undef  FLOPPY_SILENT_DCL_CLEAR
  
  #define REALLY_SLOW_IO
  
  #define DEBUGT 2

  #define DPRINT(format, args...) \
  	pr_info("floppy%d: " format, current_drive, ##args)
  
  #define DCL_DEBUG		/* debug disk change line */

  #ifdef DCL_DEBUG
  #define debug_dcl(test, fmt, args...) \
  	do { if ((test) & FD_DEBUG) DPRINT(fmt, ##args); } while (0)
  #else
  #define debug_dcl(test, fmt, args...) \
  	do { if (0) DPRINT(fmt, ##args); } while (0)
  #endif

  /* do print messages for unexpected interrupts */
  static int print_unex = 1;
  #include <linux/module.h>
  #include <linux/sched.h>
  #include <linux/fs.h>
  #include <linux/kernel.h>
  #include <linux/timer.h>
  #include <linux/workqueue.h>
  #define FDPATCHES
  #include <linux/fdreg.h>

  #include <linux/fd.h>
  #include <linux/hdreg.h>

  #include <linux/errno.h>
  #include <linux/slab.h>
  #include <linux/mm.h>
  #include <linux/bio.h>
  #include <linux/string.h>

  #include <linux/jiffies.h>

  #include <linux/fcntl.h>
  #include <linux/delay.h>
  #include <linux/mc146818rtc.h>	/* CMOS defines */
  #include <linux/ioport.h>
  #include <linux/interrupt.h>
  #include <linux/init.h>

  #include <linux/platform_device.h>

  #include <linux/mod_devicetable.h>

  #include <linux/mutex.h>

  #include <linux/io.h>
  #include <linux/uaccess.h>

  
  /*
   * PS/2 floppies have much slower step rates than regular floppies.
   * It's been recommended that take about 1/4 of the default speed
   * in some more extreme cases.
   */

  static DEFINE_MUTEX(floppy_mutex);

  static int slow_floppy;
  
  #include <asm/dma.h>
  #include <asm/irq.h>
  #include <asm/system.h>

  
  static int FLOPPY_IRQ = 6;
  static int FLOPPY_DMA = 2;
  static int can_use_virtual_dma = 2;
  /* =======
   * can use virtual DMA:
   * 0 = use of virtual DMA disallowed by config
   * 1 = use of virtual DMA prescribed by config
   * 2 = no virtual DMA preference configured.  By default try hard DMA,
   * but fall back on virtual DMA when not enough memory available
   */
  
  static int use_virtual_dma;
  /* =======
   * use virtual DMA
   * 0 using hard DMA
   * 1 using virtual DMA
   * This variable is set to virtual when a DMA mem problem arises, and
   * reset back in floppy_grab_irq_and_dma.
   * It is not safe to reset it in other circumstances, because the floppy
   * driver may have several buffers in use at once, and we do currently not
   * record each buffers capabilities
   */
  
  static DEFINE_SPINLOCK(floppy_lock);

  
  static unsigned short virtual_dma_port = 0x3f0;

  irqreturn_t floppy_interrupt(int irq, void *dev_id);

  static int set_dor(int fdc, char mask, char data);

  
  #define K_64	0x10000		/* 64KB */
  
  /* the following is the mask of allowed drives. By default units 2 and
   * 3 of both floppy controllers are disabled, because switching on the
   * motor of these drives causes system hangs on some PCI computers. drive
   * 0 is the low bit (0x1), and drive 7 is the high bit (0x80). Bits are on if
   * a drive is allowed.
   *
   * NOTE: This must come before we include the arch floppy header because
   *       some ports reference this variable from there. -DaveM
   */
  
  static int allowed_drive_mask = 0x33;
  
  #include <asm/floppy.h>
  
  static int irqdma_allocated;

  #include <linux/blkdev.h>
  #include <linux/blkpg.h>
  #include <linux/cdrom.h>	/* for the compatibility eject ioctl */
  #include <linux/completion.h>
  
  static struct request *current_req;

  static void do_fd_request(struct request_queue *q);

  static int set_next_request(void);

  
  #ifndef fd_get_dma_residue
  #define fd_get_dma_residue() get_dma_residue(FLOPPY_DMA)
  #endif
  
  /* Dma Memory related stuff */
  
  #ifndef fd_dma_mem_free
  #define fd_dma_mem_free(addr, size) free_pages(addr, get_order(size))
  #endif
  
  #ifndef fd_dma_mem_alloc

  #define fd_dma_mem_alloc(size) __get_dma_pages(GFP_KERNEL, get_order(size))

  #endif
  
  static inline void fallback_on_nodma_alloc(char **addr, size_t l)
  {
  #ifdef FLOPPY_CAN_FALLBACK_ON_NODMA
  	if (*addr)
  		return;		/* we have the memory */
  	if (can_use_virtual_dma != 2)
  		return;		/* no fallback allowed */

  	pr_info("DMA memory shortage. Temporarily falling back on virtual DMA
  ");

  	*addr = (char *)nodma_mem_alloc(l);
  #else
  	return;
  #endif
  }
  
  /* End dma memory related stuff */
  
  static unsigned long fake_change;

  static bool initialized;

  #define ITYPE(x)	(((x) >> 2) & 0x1f)
  #define TOMINOR(x)	((x & 3) | ((x & 4) << 5))
  #define UNIT(x)		((x) & 0x03)		/* drive on fdc */
  #define FDC(x)		(((x) & 0x04) >> 2)	/* fdc of drive */

  	/* reverse mapping from unit and fdc to drive */

  #define REVDRIVE(fdc, unit) ((unit) + ((fdc) << 2))

  #define DP	(&drive_params[current_drive])
  #define DRS	(&drive_state[current_drive])
  #define DRWE	(&write_errors[current_drive])
  #define FDCS	(&fdc_state[fdc])

  #define UDP	(&drive_params[drive])
  #define UDRS	(&drive_state[drive])
  #define UDRWE	(&write_errors[drive])
  #define UFDCS	(&fdc_state[FDC(drive)])

  #define PH_HEAD(floppy, head) (((((floppy)->stretch & 2) >> 1) ^ head) << 2)
  #define STRETCH(floppy)	((floppy)->stretch & FD_STRETCH)

  /* read/write */

  #define COMMAND		(raw_cmd->cmd[0])
  #define DR_SELECT	(raw_cmd->cmd[1])
  #define TRACK		(raw_cmd->cmd[2])
  #define HEAD		(raw_cmd->cmd[3])
  #define SECTOR		(raw_cmd->cmd[4])
  #define SIZECODE	(raw_cmd->cmd[5])
  #define SECT_PER_TRACK	(raw_cmd->cmd[6])
  #define GAP		(raw_cmd->cmd[7])
  #define SIZECODE2	(raw_cmd->cmd[8])

  #define NR_RW 9
  
  /* format */

  #define F_SIZECODE	(raw_cmd->cmd[2])
  #define F_SECT_PER_TRACK (raw_cmd->cmd[3])
  #define F_GAP		(raw_cmd->cmd[4])
  #define F_FILL		(raw_cmd->cmd[5])

  #define NR_F 6
  
  /*

   * Maximum disk size (in kilobytes).
   * This default is used whenever the current disk size is unknown.

   * [Now it is rather a minimum]
   */
  #define MAX_DISK_SIZE 4		/* 3984 */
  
  /*
   * globals used by 'result()'
   */
  #define MAX_REPLIES 16
  static unsigned char reply_buffer[MAX_REPLIES];

  static int inr;		/* size of reply buffer, when called from interrupt */

  #define ST0		(reply_buffer[0])
  #define ST1		(reply_buffer[1])
  #define ST2		(reply_buffer[2])
  #define ST3		(reply_buffer[0])	/* result of GETSTATUS */
  #define R_TRACK		(reply_buffer[3])
  #define R_HEAD		(reply_buffer[4])
  #define R_SECTOR	(reply_buffer[5])
  #define R_SIZECODE	(reply_buffer[6])
  
  #define SEL_DLY		(2 * HZ / 100)

  
  /*
   * this struct defines the different floppy drive types.
   */
  static struct {
  	struct floppy_drive_params params;
  	const char *name;	/* name printed while booting */
  } default_drive_params[] = {
  /* NOTE: the time values in jiffies should be in msec!
   CMOS drive type
    |     Maximum data rate supported by drive type
    |     |   Head load time, msec
    |     |   |   Head unload time, msec (not used)
    |     |   |   |     Step rate interval, usec
    |     |   |   |     |       Time needed for spinup time (jiffies)
    |     |   |   |     |       |      Timeout for spinning down (jiffies)
    |     |   |   |     |       |      |   Spindown offset (where disk stops)
    |     |   |   |     |       |      |   |     Select delay
    |     |   |   |     |       |      |   |     |     RPS
    |     |   |   |     |       |      |   |     |     |    Max number of tracks
    |     |   |   |     |       |      |   |     |     |    |     Interrupt timeout
    |     |   |   |     |       |      |   |     |     |    |     |   Max nonintlv. sectors
    |     |   |   |     |       |      |   |     |     |    |     |   | -Max Errors- flags */
  {{0,  500, 16, 16, 8000,    1*HZ, 3*HZ,  0, SEL_DLY, 5,  80, 3*HZ, 20, {3,1,2,0,2}, 0,
        0, { 7, 4, 8, 2, 1, 5, 3,10}, 3*HZ/2, 0 }, "unknown" },
  
  {{1,  300, 16, 16, 8000,    1*HZ, 3*HZ,  0, SEL_DLY, 5,  40, 3*HZ, 17, {3,1,2,0,2}, 0,
        0, { 1, 0, 0, 0, 0, 0, 0, 0}, 3*HZ/2, 1 }, "360K PC" }, /*5 1/4 360 KB PC*/
  
  {{2,  500, 16, 16, 6000, 4*HZ/10, 3*HZ, 14, SEL_DLY, 6,  83, 3*HZ, 17, {3,1,2,0,2}, 0,
        0, { 2, 5, 6,23,10,20,12, 0}, 3*HZ/2, 2 }, "1.2M" }, /*5 1/4 HD AT*/
  
  {{3,  250, 16, 16, 3000,    1*HZ, 3*HZ,  0, SEL_DLY, 5,  83, 3*HZ, 20, {3,1,2,0,2}, 0,
        0, { 4,22,21,30, 3, 0, 0, 0}, 3*HZ/2, 4 }, "720k" }, /*3 1/2 DD*/
  
  {{4,  500, 16, 16, 4000, 4*HZ/10, 3*HZ, 10, SEL_DLY, 5,  83, 3*HZ, 20, {3,1,2,0,2}, 0,
        0, { 7, 4,25,22,31,21,29,11}, 3*HZ/2, 7 }, "1.44M" }, /*3 1/2 HD*/
  
  {{5, 1000, 15,  8, 3000, 4*HZ/10, 3*HZ, 10, SEL_DLY, 5,  83, 3*HZ, 40, {3,1,2,0,2}, 0,
        0, { 7, 8, 4,25,28,22,31,21}, 3*HZ/2, 8 }, "2.88M AMI BIOS" }, /*3 1/2 ED*/
  
  {{6, 1000, 15,  8, 3000, 4*HZ/10, 3*HZ, 10, SEL_DLY, 5,  83, 3*HZ, 40, {3,1,2,0,2}, 0,
        0, { 7, 8, 4,25,28,22,31,21}, 3*HZ/2, 8 }, "2.88M" } /*3 1/2 ED*/
  /*    |  --autodetected formats---    |      |      |
   *    read_track                      |      |    Name printed when booting
   *				      |     Native format
   *	            Frequency of disk change checks */
  };
  
  static struct floppy_drive_params drive_params[N_DRIVE];
  static struct floppy_drive_struct drive_state[N_DRIVE];
  static struct floppy_write_errors write_errors[N_DRIVE];
  static struct timer_list motor_off_timer[N_DRIVE];
  static struct gendisk *disks[N_DRIVE];
  static struct block_device *opened_bdev[N_DRIVE];

  static DEFINE_MUTEX(open_lock);

  static struct floppy_raw_cmd *raw_cmd, default_raw_cmd;

  static int fdc_queue;

  
  /*
   * This struct defines the different floppy types.
   *
   * Bit 0 of 'stretch' tells if the tracks need to be doubled for some
   * types (e.g. 360kB diskette in 1.2MB drive, etc.).  Bit 1 of 'stretch'
   * tells if the disk is in Commodore 1581 format, which means side 0 sectors
   * are located on side 1 of the disk but with a side 0 ID, and vice-versa.
   * This is the same as the Sharp MZ-80 5.25" CP/M disk format, except that the
   * 1581's logical side 0 is on physical side 1, whereas the Sharp's logical
   * side 0 is on physical side 0 (but with the misnamed sector IDs).
   * 'stretch' should probably be renamed to something more general, like

   * 'options'.
   *
   * Bits 2 through 9 of 'stretch' tell the number of the first sector.
   * The LSB (bit 2) is flipped. For most disks, the first sector
   * is 1 (represented by 0x00<<2).  For some CP/M and music sampler
   * disks (such as Ensoniq EPS 16plus) it is 0 (represented as 0x01<<2).
   * For Amstrad CPC disks it is 0xC1 (represented as 0xC0<<2).
   *
   * Other parameters should be self-explanatory (see also setfdprm(8)).

   */
  /*
  	    Size
  	     |  Sectors per track
  	     |  | Head
  	     |  | |  Tracks
  	     |  | |  | Stretch
  	     |  | |  | |  Gap 1 size
  	     |  | |  | |    |  Data rate, | 0x40 for perp
  	     |  | |  | |    |    |  Spec1 (stepping rate, head unload
  	     |  | |  | |    |    |    |    /fmt gap (gap2) */
  static struct floppy_struct floppy_type[32] = {
  	{    0, 0,0, 0,0,0x00,0x00,0x00,0x00,NULL    },	/*  0 no testing    */
  	{  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"d360"  }, /*  1 360KB PC      */
  	{ 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,"h1200" },	/*  2 1.2MB AT      */
  	{  720, 9,1,80,0,0x2A,0x02,0xDF,0x50,"D360"  },	/*  3 360KB SS 3.5" */
  	{ 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"D720"  },	/*  4 720KB 3.5"    */
  	{  720, 9,2,40,1,0x23,0x01,0xDF,0x50,"h360"  },	/*  5 360KB AT      */
  	{ 1440, 9,2,80,0,0x23,0x01,0xDF,0x50,"h720"  },	/*  6 720KB AT      */
  	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,"H1440" },	/*  7 1.44MB 3.5"   */
  	{ 5760,36,2,80,0,0x1B,0x43,0xAF,0x54,"E2880" },	/*  8 2.88MB 3.5"   */
  	{ 6240,39,2,80,0,0x1B,0x43,0xAF,0x28,"E3120" },	/*  9 3.12MB 3.5"   */
  
  	{ 2880,18,2,80,0,0x25,0x00,0xDF,0x02,"h1440" }, /* 10 1.44MB 5.25"  */
  	{ 3360,21,2,80,0,0x1C,0x00,0xCF,0x0C,"H1680" }, /* 11 1.68MB 3.5"   */
  	{  820,10,2,41,1,0x25,0x01,0xDF,0x2E,"h410"  },	/* 12 410KB 5.25"   */
  	{ 1640,10,2,82,0,0x25,0x02,0xDF,0x2E,"H820"  },	/* 13 820KB 3.5"    */
  	{ 2952,18,2,82,0,0x25,0x00,0xDF,0x02,"h1476" },	/* 14 1.48MB 5.25"  */
  	{ 3444,21,2,82,0,0x25,0x00,0xDF,0x0C,"H1722" },	/* 15 1.72MB 3.5"   */
  	{  840,10,2,42,1,0x25,0x01,0xDF,0x2E,"h420"  },	/* 16 420KB 5.25"   */
  	{ 1660,10,2,83,0,0x25,0x02,0xDF,0x2E,"H830"  },	/* 17 830KB 3.5"    */
  	{ 2988,18,2,83,0,0x25,0x00,0xDF,0x02,"h1494" },	/* 18 1.49MB 5.25"  */
  	{ 3486,21,2,83,0,0x25,0x00,0xDF,0x0C,"H1743" }, /* 19 1.74 MB 3.5"  */
  
  	{ 1760,11,2,80,0,0x1C,0x09,0xCF,0x00,"h880"  }, /* 20 880KB 5.25"   */
  	{ 2080,13,2,80,0,0x1C,0x01,0xCF,0x00,"D1040" }, /* 21 1.04MB 3.5"   */
  	{ 2240,14,2,80,0,0x1C,0x19,0xCF,0x00,"D1120" }, /* 22 1.12MB 3.5"   */
  	{ 3200,20,2,80,0,0x1C,0x20,0xCF,0x2C,"h1600" }, /* 23 1.6MB 5.25"   */
  	{ 3520,22,2,80,0,0x1C,0x08,0xCF,0x2e,"H1760" }, /* 24 1.76MB 3.5"   */
  	{ 3840,24,2,80,0,0x1C,0x20,0xCF,0x00,"H1920" }, /* 25 1.92MB 3.5"   */
  	{ 6400,40,2,80,0,0x25,0x5B,0xCF,0x00,"E3200" }, /* 26 3.20MB 3.5"   */
  	{ 7040,44,2,80,0,0x25,0x5B,0xCF,0x00,"E3520" }, /* 27 3.52MB 3.5"   */
  	{ 7680,48,2,80,0,0x25,0x63,0xCF,0x00,"E3840" }, /* 28 3.84MB 3.5"   */

  	{ 3680,23,2,80,0,0x1C,0x10,0xCF,0x00,"H1840" }, /* 29 1.84MB 3.5"   */

  	{ 1600,10,2,80,0,0x25,0x02,0xDF,0x2E,"D800"  },	/* 30 800KB 3.5"    */
  	{ 3200,20,2,80,0,0x1C,0x00,0xCF,0x2C,"H1600" }, /* 31 1.6MB 3.5"    */
  };

  #define SECTSIZE (_FD_SECTSIZE(*floppy))
  
  /* Auto-detection: Disk type used until the next media change occurs. */
  static struct floppy_struct *current_type[N_DRIVE];
  
  /*
   * User-provided type information. current_type points to
   * the respective entry of this array.
   */
  static struct floppy_struct user_params[N_DRIVE];
  
  static sector_t floppy_sizes[256];

  static char floppy_device_name[] = "floppy";

  /*
   * The driver is trying to determine the correct media format
   * while probing is set. rw_interrupt() clears it after a
   * successful access.
   */
  static int probing;
  
  /* Synchronization of FDC access. */

  #define FD_COMMAND_NONE		-1
  #define FD_COMMAND_ERROR	2
  #define FD_COMMAND_OKAY		3

  
  static volatile int command_status = FD_COMMAND_NONE;
  static unsigned long fdc_busy;
  static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
  static DECLARE_WAIT_QUEUE_HEAD(command_done);

  /* Errors during formatting are counted here. */
  static int format_errors;
  
  /* Format request descriptor. */
  static struct format_descr format_req;
  
  /*
   * Rate is 0 for 500kb/s, 1 for 300kbps, 2 for 250kbps
   * Spec1 is 0xSH, where S is stepping rate (F=1ms, E=2ms, D=3ms etc),
   * H is head unload time (1=16ms, 2=32ms, etc)
   */
  
  /*
   * Track buffer
   * Because these are written to by the DMA controller, they must
   * not contain a 64k byte boundary crossing, or data will be
   * corrupted/lost.
   */
  static char *floppy_track_buffer;
  static int max_buffer_sectors;
  
  static int *errors;

  typedef void (*done_f)(int);

  static const struct cont_t {

  	void (*interrupt)(void);
  				/* this is called after the interrupt of the
  				 * main command */

  	void (*redo)(void);	/* this is called to retry the operation */
  	void (*error)(void);	/* this is called to tally an error */

  	done_f done;		/* this is called to say if the operation has
  				 * succeeded/failed */
  } *cont;
  
  static void floppy_ready(void);
  static void floppy_start(void);
  static void process_fd_request(void);
  static void recalibrate_floppy(void);
  static void floppy_shutdown(unsigned long);

  static int floppy_request_regions(int);
  static void floppy_release_regions(int);

  static int floppy_grab_irq_and_dma(void);
  static void floppy_release_irq_and_dma(void);
  
  /*
   * The "reset" variable should be tested whenever an interrupt is scheduled,
   * after the commands have been sent. This is to ensure that the driver doesn't
   * get wedged when the interrupt doesn't come because of a failed command.
   * reset doesn't need to be tested before sending commands, because
   * output_byte is automatically disabled when reset is set.
   */

  static void reset_fdc(void);
  
  /*
   * These are global variables, as that's the easiest way to give
   * information to interrupts. They are the data used for the current
   * request.
   */

  #define NO_TRACK	-1
  #define NEED_1_RECAL	-2
  #define NEED_2_RECAL	-3

  static atomic_t usage_count = ATOMIC_INIT(0);

  
  /* buffer related variables */
  static int buffer_track = -1;
  static int buffer_drive = -1;
  static int buffer_min = -1;
  static int buffer_max = -1;
  
  /* fdc related variables, should end up in a struct */
  static struct floppy_fdc_state fdc_state[N_FDC];
  static int fdc;			/* current fdc */
  
  static struct floppy_struct *_floppy = floppy_type;
  static unsigned char current_drive;
  static long current_count_sectors;
  static unsigned char fsector_t;	/* sector in track */
  static unsigned char in_sector_offset;	/* offset within physical sector,
  					 * expressed in units of 512 bytes */

  static inline bool drive_no_geom(int drive)
  {
  	return !current_type[drive] && !ITYPE(UDRS->fd_device);
  }

  #ifndef fd_eject
  static inline int fd_eject(int drive)
  {
  	return -EINVAL;
  }
  #endif
  
  /*
   * Debugging
   * =========
   */
  #ifdef DEBUGT
  static long unsigned debugtimer;
  
  static inline void set_debugt(void)
  {
  	debugtimer = jiffies;
  }

  static inline void debugt(const char *func, const char *msg)

  {
  	if (DP->flags & DEBUGT)

  		pr_info("%s:%s dtime=%lu
  ", func, msg, jiffies - debugtimer);

  }
  #else
  static inline void set_debugt(void) { }

  static inline void debugt(const char *func, const char *msg) { }

  #endif /* DEBUGT */

  typedef void (*timeout_fn)(unsigned long);

  static DEFINE_TIMER(fd_timeout, floppy_shutdown, 0, 0);

  
  static const char *timeout_message;

  static void is_alive(const char *func, const char *message)

  {
  	/* this routine checks whether the floppy driver is "alive" */

  	if (test_bit(0, &fdc_busy) && command_status < 2 &&
  	    !timer_pending(&fd_timeout)) {

  		DPRINT("%s: timeout handler died.  %s
  ", func, message);

  	}
  }

  static void (*do_floppy)(void) = NULL;

  #define OLOGSIZE 20

  static void (*lasthandler)(void);

  static unsigned long interruptjiffies;
  static unsigned long resultjiffies;
  static int resultsize;
  static unsigned long lastredo;
  
  static struct output_log {
  	unsigned char data;
  	unsigned char status;
  	unsigned long jiffies;
  } output_log[OLOGSIZE];
  
  static int output_log_pos;

  
  #define current_reqD -1
  #define MAXTIMEOUT -2

  static void __reschedule_timeout(int drive, const char *message)

  {
  	if (drive == current_reqD)
  		drive = current_drive;
  	del_timer(&fd_timeout);

  	if (drive < 0 || drive >= N_DRIVE) {

  		fd_timeout.expires = jiffies + 20UL * HZ;
  		drive = 0;
  	} else
  		fd_timeout.expires = jiffies + UDP->timeout;
  	add_timer(&fd_timeout);

  	if (UDP->flags & FD_DEBUG)

  		DPRINT("reschedule timeout %s
  ", message);

  	timeout_message = message;
  }

  static void reschedule_timeout(int drive, const char *message)

  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&floppy_lock, flags);

  	__reschedule_timeout(drive, message);

  	spin_unlock_irqrestore(&floppy_lock, flags);
  }

  #define INFBOUND(a, b) (a) = max_t(int, a, b)
  #define SUPBOUND(a, b) (a) = min_t(int, a, b)

  
  /*
   * Bottom half floppy driver.
   * ==========================
   *
   * This part of the file contains the code talking directly to the hardware,
   * and also the main service loop (seek-configure-spinup-command)
   */
  
  /*
   * disk change.
   * This routine is responsible for maintaining the FD_DISK_CHANGE flag,
   * and the last_checked date.
   *
   * last_checked is the date of the last check which showed 'no disk change'
   * FD_DISK_CHANGE is set under two conditions:
   * 1. The floppy has been changed after some i/o to that floppy already
   *    took place.
   * 2. No floppy disk is in the drive. This is done in order to ensure that
   *    requests are quickly flushed in case there is no disk in the drive. It
   *    follows that FD_DISK_CHANGE can only be cleared if there is a disk in
   *    the drive.
   *
   * For 1., maxblock is observed. Maxblock is 0 if no i/o has taken place yet.
   * For 2., FD_DISK_NEWCHANGE is watched. FD_DISK_NEWCHANGE is cleared on
   *  each seek. If a disk is present, the disk change line should also be
   *  cleared on each seek. Thus, if FD_DISK_NEWCHANGE is clear, but the disk
   *  change line is set, this means either that no disk is in the drive, or
   *  that it has been removed since the last seek.
   *
   * This means that we really have a third possibility too:
   *  The floppy has been changed after the last seek.
   */
  
  static int disk_change(int drive)
  {
  	int fdc = FDC(drive);

  	if (time_before(jiffies, UDRS->select_date + UDP->select_delay))

  		DPRINT("WARNING disk change called early
  ");
  	if (!(FDCS->dor & (0x10 << UNIT(drive))) ||
  	    (FDCS->dor & 3) != UNIT(drive) || fdc != FDC(drive)) {
  		DPRINT("probing disk change on unselected drive
  ");
  		DPRINT("drive=%d fdc=%d dor=%x
  ", drive, FDC(drive),
  		       (unsigned int)FDCS->dor);
  	}

  	debug_dcl(UDP->flags,
  		  "checking disk change line for drive %d
  ", drive);
  	debug_dcl(UDP->flags, "jiffies=%lu
  ", jiffies);
  	debug_dcl(UDP->flags, "disk change line=%x
  ", fd_inb(FD_DIR) & 0x80);
  	debug_dcl(UDP->flags, "flags=%lx
  ", UDRS->flags);

  	if (UDP->flags & FD_BROKEN_DCL)

  		return test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags);

  	if ((fd_inb(FD_DIR) ^ UDP->flags) & 0x80) {

  		set_bit(FD_VERIFY_BIT, &UDRS->flags);
  					/* verify write protection */
  
  		if (UDRS->maxblock)	/* mark it changed */
  			set_bit(FD_DISK_CHANGED_BIT, &UDRS->flags);

  
  		/* invalidate its geometry */
  		if (UDRS->keep_data >= 0) {
  			if ((UDP->flags & FTD_MSG) &&
  			    current_type[drive] != NULL)

  				DPRINT("Disk type is undefined after disk change
  ");

  			current_type[drive] = NULL;
  			floppy_sizes[TOMINOR(drive)] = MAX_DISK_SIZE << 1;
  		}

  		return 1;
  	} else {
  		UDRS->last_checked = jiffies;

  		clear_bit(FD_DISK_NEWCHANGE_BIT, &UDRS->flags);

  	}
  	return 0;
  }
  
  static inline int is_selected(int dor, int unit)
  {
  	return ((dor & (0x10 << unit)) && (dor & 3) == unit);
  }

  static bool is_ready_state(int status)
  {
  	int state = status & (STATUS_READY | STATUS_DIR | STATUS_DMA);
  	return state == STATUS_READY;
  }

  static int set_dor(int fdc, char mask, char data)
  {

  	unsigned char unit;
  	unsigned char drive;
  	unsigned char newdor;
  	unsigned char olddor;

  
  	if (FDCS->address == -1)
  		return -1;
  
  	olddor = FDCS->dor;
  	newdor = (olddor & mask) | data;
  	if (newdor != olddor) {
  		unit = olddor & 0x3;
  		if (is_selected(olddor, unit) && !is_selected(newdor, unit)) {
  			drive = REVDRIVE(fdc, unit);

  			debug_dcl(UDP->flags,
  				  "calling disk change from set_dor
  ");

  			disk_change(drive);
  		}
  		FDCS->dor = newdor;
  		fd_outb(newdor, FD_DOR);
  
  		unit = newdor & 0x3;
  		if (!is_selected(olddor, unit) && is_selected(newdor, unit)) {
  			drive = REVDRIVE(fdc, unit);
  			UDRS->select_date = jiffies;
  		}
  	}

  	return olddor;
  }
  
  static void twaddle(void)
  {
  	if (DP->select_delay)
  		return;
  	fd_outb(FDCS->dor & ~(0x10 << UNIT(current_drive)), FD_DOR);
  	fd_outb(FDCS->dor, FD_DOR);
  	DRS->select_date = jiffies;
  }

  /*
   * Reset all driver information about the current fdc.
   * This is needed after a reset, and after a raw command.
   */

  static void reset_fdc_info(int mode)
  {
  	int drive;
  
  	FDCS->spec1 = FDCS->spec2 = -1;
  	FDCS->need_configure = 1;
  	FDCS->perp_mode = 1;
  	FDCS->rawcmd = 0;
  	for (drive = 0; drive < N_DRIVE; drive++)
  		if (FDC(drive) == fdc && (mode || UDRS->track != NEED_1_RECAL))
  			UDRS->track = NEED_2_RECAL;
  }
  
  /* selects the fdc and drive, and enables the fdc's input/dma. */
  static void set_fdc(int drive)
  {
  	if (drive >= 0 && drive < N_DRIVE) {
  		fdc = FDC(drive);
  		current_drive = drive;
  	}
  	if (fdc != 1 && fdc != 0) {

  		pr_info("bad fdc value
  ");

  		return;
  	}
  	set_dor(fdc, ~0, 8);
  #if N_FDC > 1
  	set_dor(1 - fdc, ~8, 0);
  #endif
  	if (FDCS->rawcmd == 2)
  		reset_fdc_info(1);
  	if (fd_inb(FD_STATUS) != STATUS_READY)
  		FDCS->reset = 1;
  }
  
  /* locks the driver */

  static int lock_fdc(int drive, bool interruptible)

  {

  	if (WARN(atomic_read(&usage_count) == 0,
  		 "Trying to lock fdc while usage count=0
  "))

  		return -1;

  	if (wait_event_interruptible(fdc_wait, !test_and_set_bit(0, &fdc_busy)))
  		return -EINTR;

  	command_status = FD_COMMAND_NONE;

  	__reschedule_timeout(drive, "lock fdc");

  	set_fdc(drive);
  	return 0;
  }

  /* unlocks the driver */

  static void unlock_fdc(void)

  {
  	unsigned long flags;
  
  	raw_cmd = NULL;
  	if (!test_bit(0, &fdc_busy))
  		DPRINT("FDC access conflict!
  ");
  
  	if (do_floppy)

  		DPRINT("device interrupt still active at FDC release: %pf!
  ",

  		       do_floppy);
  	command_status = FD_COMMAND_NONE;
  	spin_lock_irqsave(&floppy_lock, flags);
  	del_timer(&fd_timeout);
  	cont = NULL;
  	clear_bit(0, &fdc_busy);

  	if (current_req || set_next_request())
  		do_fd_request(current_req->q);

  	spin_unlock_irqrestore(&floppy_lock, flags);

  	wake_up(&fdc_wait);
  }
  
  /* switches the motor off after a given timeout */
  static void motor_off_callback(unsigned long nr)
  {
  	unsigned char mask = ~(0x10 << UNIT(nr));
  
  	set_dor(FDC(nr), mask, 0);
  }
  
  /* schedules motor off */
  static void floppy_off(unsigned int drive)
  {
  	unsigned long volatile delta;

  	int fdc = FDC(drive);

  
  	if (!(FDCS->dor & (0x10 << UNIT(drive))))
  		return;
  
  	del_timer(motor_off_timer + drive);
  
  	/* make spindle stop in a position which minimizes spinup time
  	 * next time */
  	if (UDP->rps) {
  		delta = jiffies - UDRS->first_read_date + HZ -
  		    UDP->spindown_offset;
  		delta = ((delta * UDP->rps) % HZ) / UDP->rps;
  		motor_off_timer[drive].expires =
  		    jiffies + UDP->spindown - delta;
  	}
  	add_timer(motor_off_timer + drive);
  }
  
  /*
   * cycle through all N_DRIVE floppy drives, for disk change testing.
   * stopping at current drive. This is done before any long operation, to
   * be sure to have up to date disk change information.
   */
  static void scandrives(void)
  {

  	int i;
  	int drive;
  	int saved_drive;

  
  	if (DP->select_delay)
  		return;
  
  	saved_drive = current_drive;
  	for (i = 0; i < N_DRIVE; i++) {
  		drive = (saved_drive + i + 1) % N_DRIVE;
  		if (UDRS->fd_ref == 0 || UDP->select_delay != 0)
  			continue;	/* skip closed drives */
  		set_fdc(drive);
  		if (!(set_dor(fdc, ~3, UNIT(drive) | (0x10 << UNIT(drive))) &
  		      (0x10 << UNIT(drive))))
  			/* switch the motor off again, if it was off to
  			 * begin with */
  			set_dor(fdc, ~(0x10 << UNIT(drive)), 0);
  	}
  	set_fdc(saved_drive);
  }
  
  static void empty(void)
  {
  }

  static DECLARE_WORK(floppy_work, NULL);

  static void schedule_bh(void (*handler)(void))

  {

  	PREPARE_WORK(&floppy_work, (work_func_t)handler);

  	schedule_work(&floppy_work);
  }

  static DEFINE_TIMER(fd_timer, NULL, 0, 0);

  
  static void cancel_activity(void)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&floppy_lock, flags);
  	do_floppy = NULL;

  	PREPARE_WORK(&floppy_work, (work_func_t)empty);

  	del_timer(&fd_timer);
  	spin_unlock_irqrestore(&floppy_lock, flags);
  }
  
  /* this function makes sure that the disk stays in the drive during the
   * transfer */
  static void fd_watchdog(void)
  {

  	debug_dcl(DP->flags, "calling disk change from watchdog
  ");

  
  	if (disk_change(current_drive)) {
  		DPRINT("disk removed during i/o
  ");
  		cancel_activity();
  		cont->done(0);
  		reset_fdc();
  	} else {
  		del_timer(&fd_timer);

  		fd_timer.function = (timeout_fn)fd_watchdog;

  		fd_timer.expires = jiffies + HZ / 10;
  		add_timer(&fd_timer);
  	}
  }
  
  static void main_command_interrupt(void)
  {
  	del_timer(&fd_timer);
  	cont->interrupt();
  }
  
  /* waits for a delay (spinup or select) to pass */
  static int fd_wait_for_completion(unsigned long delay, timeout_fn function)
  {
  	if (FDCS->reset) {
  		reset_fdc();	/* do the reset during sleep to win time
  				 * if we don't need to sleep, it's a good
  				 * occasion anyways */
  		return 1;
  	}

  	if (time_before(jiffies, delay)) {

  		del_timer(&fd_timer);
  		fd_timer.function = function;
  		fd_timer.expires = delay;
  		add_timer(&fd_timer);
  		return 1;
  	}
  	return 0;
  }
  
  static DEFINE_SPINLOCK(floppy_hlt_lock);
  static int hlt_disabled;
  static void floppy_disable_hlt(void)
  {
  	unsigned long flags;

  	WARN_ONCE(1, "floppy_disable_hlt() scheduled for removal in 2012");

  	spin_lock_irqsave(&floppy_hlt_lock, flags);
  	if (!hlt_disabled) {
  		hlt_disabled = 1;
  #ifdef HAVE_DISABLE_HLT
  		disable_hlt();
  #endif
  	}
  	spin_unlock_irqrestore(&floppy_hlt_lock, flags);
  }
  
  static void floppy_enable_hlt(void)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&floppy_hlt_lock, flags);
  	if (hlt_disabled) {
  		hlt_disabled = 0;
  #ifdef HAVE_DISABLE_HLT
  		enable_hlt();
  #endif
  	}
  	spin_unlock_irqrestore(&floppy_hlt_lock, flags);
  }
  
  static void setup_DMA(void)
  {
  	unsigned long f;

  	if (raw_cmd->length == 0) {
  		int i;

  		pr_info("zero dma transfer size:");

  		for (i = 0; i < raw_cmd->cmd_count; i++)

  			pr_cont("%x,", raw_cmd->cmd[i]);
  		pr_cont("
  ");

  		cont->done(0);
  		FDCS->reset = 1;
  		return;
  	}
  	if (((unsigned long)raw_cmd->kernel_data) % 512) {

  		pr_info("non aligned address: %p
  ", raw_cmd->kernel_data);

  		cont->done(0);
  		FDCS->reset = 1;
  		return;
  	}

  	f = claim_dma_lock();
  	fd_disable_dma();
  #ifdef fd_dma_setup
  	if (fd_dma_setup(raw_cmd->kernel_data, raw_cmd->length,
  			 (raw_cmd->flags & FD_RAW_READ) ?
  			 DMA_MODE_READ : DMA_MODE_WRITE, FDCS->address) < 0) {
  		release_dma_lock(f);
  		cont->done(0);
  		FDCS->reset = 1;
  		return;
  	}
  	release_dma_lock(f);
  #else
  	fd_clear_dma_ff();
  	fd_cacheflush(raw_cmd->kernel_data, raw_cmd->length);
  	fd_set_dma_mode((raw_cmd->flags & FD_RAW_READ) ?
  			DMA_MODE_READ : DMA_MODE_WRITE);
  	fd_set_dma_addr(raw_cmd->kernel_data);
  	fd_set_dma_count(raw_cmd->length);
  	virtual_dma_port = FDCS->address;
  	fd_enable_dma();
  	release_dma_lock(f);
  #endif
  	floppy_disable_hlt();
  }
  
  static void show_floppy(void);
  
  /* waits until the fdc becomes ready */
  static int wait_til_ready(void)
  {

  	int status;
  	int counter;

  	if (FDCS->reset)
  		return -1;
  	for (counter = 0; counter < 10000; counter++) {
  		status = fd_inb(FD_STATUS);
  		if (status & STATUS_READY)
  			return status;
  	}

  	if (initialized) {

  		DPRINT("Getstatus times out (%x) on fdc %d
  ", status, fdc);
  		show_floppy();
  	}
  	FDCS->reset = 1;
  	return -1;
  }
  
  /* sends a command byte to the fdc */
  static int output_byte(char byte)
  {

  	int status = wait_til_ready();

  	if (status < 0)

  		return -1;

  
  	if (is_ready_state(status)) {

  		fd_outb(byte, FD_DATA);

  		output_log[output_log_pos].data = byte;
  		output_log[output_log_pos].status = status;
  		output_log[output_log_pos].jiffies = jiffies;
  		output_log_pos = (output_log_pos + 1) % OLOGSIZE;

  		return 0;
  	}
  	FDCS->reset = 1;

  	if (initialized) {

  		DPRINT("Unable to send byte %x to FDC. Fdc=%x Status=%x
  ",
  		       byte, fdc, status);
  		show_floppy();
  	}
  	return -1;
  }

  /* gets the response from the fdc */
  static int result(void)
  {

  	int i;
  	int status = 0;

  
  	for (i = 0; i < MAX_REPLIES; i++) {

  		status = wait_til_ready();
  		if (status < 0)

  			break;
  		status &= STATUS_DIR | STATUS_READY | STATUS_BUSY | STATUS_DMA;
  		if ((status & ~STATUS_BUSY) == STATUS_READY) {

  			resultjiffies = jiffies;
  			resultsize = i;

  			return i;
  		}
  		if (status == (STATUS_DIR | STATUS_READY | STATUS_BUSY))
  			reply_buffer[i] = fd_inb(FD_DATA);
  		else
  			break;
  	}

  	if (initialized) {
  		DPRINT("get result error. Fdc=%d Last status=%x Read bytes=%d
  ",
  		       fdc, status, i);

  		show_floppy();
  	}
  	FDCS->reset = 1;
  	return -1;
  }
  
  #define MORE_OUTPUT -2
  /* does the fdc need more output? */
  static int need_more_output(void)
  {

  	int status = wait_til_ready();

  	if (status < 0)

  		return -1;

  
  	if (is_ready_state(status))

  		return MORE_OUTPUT;

  	return result();
  }
  
  /* Set perpendicular mode as required, based on data rate, if supported.
   * 82077 Now tested. 1Mbps data rate only possible with 82077-1.
   */

  static void perpendicular_mode(void)

  {
  	unsigned char perp_mode;
  
  	if (raw_cmd->rate & 0x40) {
  		switch (raw_cmd->rate & 3) {
  		case 0:
  			perp_mode = 2;
  			break;
  		case 3:
  			perp_mode = 3;
  			break;
  		default:
  			DPRINT("Invalid data rate for perpendicular mode!
  ");
  			cont->done(0);

  			FDCS->reset = 1;
  					/*
  					 * convenient way to return to
  					 * redo without too much hassle
  					 * (deep stack et al.)
  					 */

  			return;
  		}
  	} else
  		perp_mode = 0;
  
  	if (FDCS->perp_mode == perp_mode)
  		return;
  	if (FDCS->version >= FDC_82077_ORIG) {
  		output_byte(FD_PERPENDICULAR);
  		output_byte(perp_mode);
  		FDCS->perp_mode = perp_mode;
  	} else if (perp_mode) {
  		DPRINT("perpendicular mode not supported by this FDC.
  ");
  	}
  }				/* perpendicular_mode */
  
  static int fifo_depth = 0xa;
  static int no_fifo;
  
  static int fdc_configure(void)
  {
  	/* Turn on FIFO */
  	output_byte(FD_CONFIGURE);
  	if (need_more_output() != MORE_OUTPUT)
  		return 0;
  	output_byte(0);
  	output_byte(0x10 | (no_fifo & 0x20) | (fifo_depth & 0xf));
  	output_byte(0);		/* pre-compensation from track
  				   0 upwards */
  	return 1;
  }
  
  #define NOMINAL_DTR 500
  
  /* Issue a "SPECIFY" command to set the step rate time, head unload time,
   * head load time, and DMA disable flag to values needed by floppy.
   *
   * The value "dtr" is the data transfer rate in Kbps.  It is needed
   * to account for the data rate-based scaling done by the 82072 and 82077
   * FDC types.  This parameter is ignored for other types of FDCs (i.e.
   * 8272a).
   *
   * Note that changing the data transfer rate has a (probably deleterious)
   * effect on the parameters subject to scaling for 82072/82077 FDCs, so
   * fdc_specify is called again after each data transfer rate
   * change.
   *
   * srt: 1000 to 16000 in microseconds
   * hut: 16 to 240 milliseconds
   * hlt: 2 to 254 milliseconds
   *
   * These values are rounded up to the next highest available delay time.
   */
  static void fdc_specify(void)
  {

  	unsigned char spec1;
  	unsigned char spec2;
  	unsigned long srt;
  	unsigned long hlt;
  	unsigned long hut;

  	unsigned long dtr = NOMINAL_DTR;
  	unsigned long scale_dtr = NOMINAL_DTR;
  	int hlt_max_code = 0x7f;
  	int hut_max_code = 0xf;
  
  	if (FDCS->need_configure && FDCS->version >= FDC_82072A) {
  		fdc_configure();
  		FDCS->need_configure = 0;

  	}
  
  	switch (raw_cmd->rate & 0x03) {
  	case 3:
  		dtr = 1000;
  		break;
  	case 1:
  		dtr = 300;
  		if (FDCS->version >= FDC_82078) {
  			/* chose the default rate table, not the one
  			 * where 1 = 2 Mbps */
  			output_byte(FD_DRIVESPEC);
  			if (need_more_output() == MORE_OUTPUT) {
  				output_byte(UNIT(current_drive));
  				output_byte(0xc0);
  			}
  		}
  		break;
  	case 2:
  		dtr = 250;
  		break;
  	}
  
  	if (FDCS->version >= FDC_82072) {
  		scale_dtr = dtr;
  		hlt_max_code = 0x00;	/* 0==256msec*dtr0/dtr (not linear!) */
  		hut_max_code = 0x0;	/* 0==256msec*dtr0/dtr (not linear!) */
  	}
  
  	/* Convert step rate from microseconds to milliseconds and 4 bits */

  	srt = 16 - DIV_ROUND_UP(DP->srt * scale_dtr / 1000, NOMINAL_DTR);

  	if (slow_floppy)

  		srt = srt / 4;

  	SUPBOUND(srt, 0xf);
  	INFBOUND(srt, 0);

  	hlt = DIV_ROUND_UP(DP->hlt * scale_dtr / 2, NOMINAL_DTR);

  	if (hlt < 0x01)
  		hlt = 0x01;
  	else if (hlt > 0x7f)
  		hlt = hlt_max_code;

  	hut = DIV_ROUND_UP(DP->hut * scale_dtr / 16, NOMINAL_DTR);

  	if (hut < 0x1)
  		hut = 0x1;
  	else if (hut > 0xf)
  		hut = hut_max_code;
  
  	spec1 = (srt << 4) | hut;
  	spec2 = (hlt << 1) | (use_virtual_dma & 1);
  
  	/* If these parameters did not change, just return with success */
  	if (FDCS->spec1 != spec1 || FDCS->spec2 != spec2) {
  		/* Go ahead and set spec1 and spec2 */
  		output_byte(FD_SPECIFY);
  		output_byte(FDCS->spec1 = spec1);
  		output_byte(FDCS->spec2 = spec2);
  	}
  }				/* fdc_specify */
  
  /* Set the FDC's data transfer rate on behalf of the specified drive.
   * NOTE: with 82072/82077 FDCs, changing the data rate requires a reissue
   * of the specify command (i.e. using the fdc_specify function).
   */
  static int fdc_dtr(void)
  {
  	/* If data rate not already set to desired value, set it. */
  	if ((raw_cmd->rate & 3) == FDCS->dtr)
  		return 0;
  
  	/* Set dtr */
  	fd_outb(raw_cmd->rate & 3, FD_DCR);
  
  	/* TODO: some FDC/drive combinations (C&T 82C711 with TEAC 1.2MB)
  	 * need a stabilization period of several milliseconds to be
  	 * enforced after data rate changes before R/W operations.
  	 * Pause 5 msec to avoid trouble. (Needs to be 2 jiffies)
  	 */
  	FDCS->dtr = raw_cmd->rate & 3;

  	return fd_wait_for_completion(jiffies + 2UL * HZ / 100,
  				      (timeout_fn)floppy_ready);

  }				/* fdc_dtr */
  
  static void tell_sector(void)
  {

  	pr_cont(": track %d, head %d, sector %d, size %d",
  		R_TRACK, R_HEAD, R_SECTOR, R_SIZECODE);

  }				/* tell_sector */

  static void print_errors(void)
  {
  	DPRINT("");
  	if (ST0 & ST0_ECE) {
  		pr_cont("Recalibrate failed!");
  	} else if (ST2 & ST2_CRC) {
  		pr_cont("data CRC error");
  		tell_sector();
  	} else if (ST1 & ST1_CRC) {
  		pr_cont("CRC error");
  		tell_sector();
  	} else if ((ST1 & (ST1_MAM | ST1_ND)) ||
  		   (ST2 & ST2_MAM)) {
  		if (!probing) {
  			pr_cont("sector not found");
  			tell_sector();
  		} else
  			pr_cont("probe failed...");
  	} else if (ST2 & ST2_WC) {	/* seek error */
  		pr_cont("wrong cylinder");
  	} else if (ST2 & ST2_BC) {	/* cylinder marked as bad */
  		pr_cont("bad cylinder");
  	} else {
  		pr_cont("unknown error. ST[0..2] are: 0x%x 0x%x 0x%x",
  			ST0, ST1, ST2);
  		tell_sector();
  	}
  	pr_cont("
  ");
  }

  /*
   * OK, this error interpreting routine is called after a
   * DMA read/write has succeeded
   * or failed, so we check the results, and copy any buffers.
   * hhb: Added better error reporting.
   * ak: Made this into a separate routine.
   */
  static int interpret_errors(void)
  {
  	char bad;
  
  	if (inr != 7) {

  		DPRINT("-- FDC reply error
  ");

  		FDCS->reset = 1;
  		return 1;
  	}
  
  	/* check IC to find cause of interrupt */
  	switch (ST0 & ST0_INTR) {
  	case 0x40:		/* error occurred during command execution */
  		if (ST1 & ST1_EOC)
  			return 0;	/* occurs with pseudo-DMA */
  		bad = 1;
  		if (ST1 & ST1_WP) {
  			DPRINT("Drive is write protected
  ");

  			clear_bit(FD_DISK_WRITABLE_BIT, &DRS->flags);

  			cont->done(0);
  			bad = 2;
  		} else if (ST1 & ST1_ND) {

  			set_bit(FD_NEED_TWADDLE_BIT, &DRS->flags);

  		} else if (ST1 & ST1_OR) {
  			if (DP->flags & FTD_MSG)
  				DPRINT("Over/Underrun - retrying
  ");
  			bad = 0;
  		} else if (*errors >= DP->max_errors.reporting) {

  			print_errors();

  		}
  		if (ST2 & ST2_WC || ST2 & ST2_BC)
  			/* wrong cylinder => recal */
  			DRS->track = NEED_2_RECAL;
  		return bad;
  	case 0x80:		/* invalid command given */
  		DPRINT("Invalid FDC command given!
  ");
  		cont->done(0);
  		return 2;
  	case 0xc0:
  		DPRINT("Abnormal termination caused by polling
  ");
  		cont->error();
  		return 2;
  	default:		/* (0) Normal command termination */
  		return 0;
  	}
  }
  
  /*
   * This routine is called when everything should be correctly set up
   * for the transfer (i.e. floppy motor is on, the correct floppy is
   * selected, and the head is sitting on the right track).
   */
  static void setup_rw_floppy(void)
  {

  	int i;
  	int r;
  	int flags;
  	int dflags;

  	unsigned long ready_date;
  	timeout_fn function;
  
  	flags = raw_cmd->flags;
  	if (flags & (FD_RAW_READ | FD_RAW_WRITE))
  		flags |= FD_RAW_INTR;
  
  	if ((flags & FD_RAW_SPIN) && !(flags & FD_RAW_NO_MOTOR)) {
  		ready_date = DRS->spinup_date + DP->spinup;
  		/* If spinup will take a long time, rerun scandrives
  		 * again just before spinup completion. Beware that
  		 * after scandrives, we must again wait for selection.
  		 */

  		if (time_after(ready_date, jiffies + DP->select_delay)) {

  			ready_date -= DP->select_delay;

  			function = (timeout_fn)floppy_start;

  		} else

  			function = (timeout_fn)setup_rw_floppy;

  
  		/* wait until the floppy is spinning fast enough */
  		if (fd_wait_for_completion(ready_date, function))
  			return;
  	}
  	dflags = DRS->flags;
  
  	if ((flags & FD_RAW_READ) || (flags & FD_RAW_WRITE))
  		setup_DMA();
  
  	if (flags & FD_RAW_INTR)
  		do_floppy = main_command_interrupt;
  
  	r = 0;
  	for (i = 0; i < raw_cmd->cmd_count; i++)
  		r |= output_byte(raw_cmd->cmd[i]);

  	debugt(__func__, "rw_command");

  
  	if (r) {
  		cont->error();
  		reset_fdc();
  		return;
  	}
  
  	if (!(flags & FD_RAW_INTR)) {
  		inr = result();
  		cont->interrupt();
  	} else if (flags & FD_RAW_NEED_DISK)
  		fd_watchdog();
  }
  
  static int blind_seek;
  
  /*
   * This is the routine called after every seek (or recalibrate) interrupt
   * from the floppy controller.
   */
  static void seek_interrupt(void)
  {

  	debugt(__func__, "");

  	if (inr != 2 || (ST0 & 0xF8) != 0x20) {
  		DPRINT("seek failed
  ");
  		DRS->track = NEED_2_RECAL;
  		cont->error();
  		cont->redo();
  		return;
  	}
  	if (DRS->track >= 0 && DRS->track != ST1 && !blind_seek) {

  		debug_dcl(DP->flags,
  			  "clearing NEWCHANGE flag because of effective seek
  ");
  		debug_dcl(DP->flags, "jiffies=%lu
  ", jiffies);

  		clear_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags);
  					/* effective seek */

  		DRS->select_date = jiffies;
  	}
  	DRS->track = ST1;
  	floppy_ready();
  }
  
  static void check_wp(void)
  {

  	if (test_bit(FD_VERIFY_BIT, &DRS->flags)) {
  					/* check write protection */

  		output_byte(FD_GETSTATUS);
  		output_byte(UNIT(current_drive));
  		if (result() != 1) {
  			FDCS->reset = 1;
  			return;
  		}

  		clear_bit(FD_VERIFY_BIT, &DRS->flags);
  		clear_bit(FD_NEED_TWADDLE_BIT, &DRS->flags);

  		debug_dcl(DP->flags,
  			  "checking whether disk is write protected
  ");
  		debug_dcl(DP->flags, "wp=%x
  ", ST3 & 0x40);

  		if (!(ST3 & 0x40))

  			set_bit(FD_DISK_WRITABLE_BIT, &DRS->flags);

  		else

  			clear_bit(FD_DISK_WRITABLE_BIT, &DRS->flags);

  	}
  }
  
  static void seek_floppy(void)
  {
  	int track;
  
  	blind_seek = 0;

  	debug_dcl(DP->flags, "calling disk change from %s
  ", __func__);

  	if (!test_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags) &&

  	    disk_change(current_drive) && (raw_cmd->flags & FD_RAW_NEED_DISK)) {
  		/* the media changed flag should be cleared after the seek.
  		 * If it isn't, this means that there is really no disk in
  		 * the drive.
  		 */

  		set_bit(FD_DISK_CHANGED_BIT, &DRS->flags);

  		cont->done(0);
  		cont->redo();
  		return;
  	}
  	if (DRS->track <= NEED_1_RECAL) {
  		recalibrate_floppy();
  		return;

  	} else if (test_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags) &&

  		   (raw_cmd->flags & FD_RAW_NEED_DISK) &&
  		   (DRS->track <= NO_TRACK || DRS->track == raw_cmd->track)) {
  		/* we seek to clear the media-changed condition. Does anybody
  		 * know a more elegant way, which works on all drives? */
  		if (raw_cmd->track)
  			track = raw_cmd->track - 1;
  		else {
  			if (DP->flags & FD_SILENT_DCL_CLEAR) {
  				set_dor(fdc, ~(0x10 << UNIT(current_drive)), 0);
  				blind_seek = 1;
  				raw_cmd->flags |= FD_RAW_NEED_SEEK;
  			}
  			track = 1;
  		}
  	} else {
  		check_wp();
  		if (raw_cmd->track != DRS->track &&
  		    (raw_cmd->flags & FD_RAW_NEED_SEEK))
  			track = raw_cmd->track;
  		else {
  			setup_rw_floppy();
  			return;
  		}
  	}
  
  	do_floppy = seek_interrupt;
  	output_byte(FD_SEEK);
  	output_byte(UNIT(current_drive));

  	if (output_byte(track) < 0) {
  		reset_fdc();
  		return;
  	}

  	debugt(__func__, "");

  }
  
  static void recal_interrupt(void)
  {

  	debugt(__func__, "");

  	if (inr != 2)
  		FDCS->reset = 1;
  	else if (ST0 & ST0_ECE) {
  		switch (DRS->track) {
  		case NEED_1_RECAL:

  			debugt(__func__, "need 1 recal");

  			/* after a second recalibrate, we still haven't
  			 * reached track 0. Probably no drive. Raise an
  			 * error, as failing immediately might upset
  			 * computers possessed by the Devil :-) */
  			cont->error();
  			cont->redo();
  			return;
  		case NEED_2_RECAL:

  			debugt(__func__, "need 2 recal");

  			/* If we already did a recalibrate,
  			 * and we are not at track 0, this
  			 * means we have moved. (The only way
  			 * not to move at recalibration is to
  			 * be already at track 0.) Clear the
  			 * new change flag */

  			debug_dcl(DP->flags,
  				  "clearing NEWCHANGE flag because of second recalibrate
  ");

  			clear_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags);

  			DRS->select_date = jiffies;
  			/* fall through */
  		default:

  			debugt(__func__, "default");

  			/* Recalibrate moves the head by at
  			 * most 80 steps. If after one
  			 * recalibrate we don't have reached
  			 * track 0, this might mean that we
  			 * started beyond track 80.  Try
  			 * again.  */
  			DRS->track = NEED_1_RECAL;
  			break;
  		}
  	} else
  		DRS->track = ST1;
  	floppy_ready();
  }
  
  static void print_result(char *message, int inr)
  {
  	int i;
  
  	DPRINT("%s ", message);
  	if (inr >= 0)
  		for (i = 0; i < inr; i++)

  			pr_cont("repl[%d]=%x ", i, reply_buffer[i]);
  	pr_cont("
  ");

  }
  
  /* interrupt handler. Note that this can be called externally on the Sparc */

  irqreturn_t floppy_interrupt(int irq, void *dev_id)

  {

  	int do_print;
  	unsigned long f;

  	void (*handler)(void) = do_floppy;

  
  	lasthandler = handler;
  	interruptjiffies = jiffies;
  
  	f = claim_dma_lock();
  	fd_disable_dma();
  	release_dma_lock(f);
  
  	floppy_enable_hlt();
  	do_floppy = NULL;
  	if (fdc >= N_FDC || FDCS->address == -1) {
  		/* we don't even know which FDC is the culprit */

  		pr_info("DOR0=%x
  ", fdc_state[0].dor);
  		pr_info("floppy interrupt on bizarre fdc %d
  ", fdc);

  		pr_info("handler=%pf
  ", handler);

  		is_alive(__func__, "bizarre fdc");

  		return IRQ_NONE;
  	}
  
  	FDCS->reset = 0;
  	/* We have to clear the reset flag here, because apparently on boxes
  	 * with level triggered interrupts (PS/2, Sparc, ...), it is needed to
  	 * emit SENSEI's to clear the interrupt line. And FDCS->reset blocks the
  	 * emission of the SENSEI's.
  	 * It is OK to emit floppy commands because we are in an interrupt
  	 * handler here, and thus we have to fear no interference of other
  	 * activity.
  	 */

  	do_print = !handler && print_unex && initialized;

  
  	inr = result();
  	if (do_print)
  		print_result("unexpected interrupt", inr);
  	if (inr == 0) {
  		int max_sensei = 4;
  		do {
  			output_byte(FD_SENSEI);
  			inr = result();
  			if (do_print)
  				print_result("sensei", inr);
  			max_sensei--;

  		} while ((ST0 & 0x83) != UNIT(current_drive) &&
  			 inr == 2 && max_sensei);

  	}
  	if (!handler) {
  		FDCS->reset = 1;
  		return IRQ_NONE;
  	}
  	schedule_bh(handler);

  	is_alive(__func__, "normal interrupt end");

  
  	/* FIXME! Was it really for us? */
  	return IRQ_HANDLED;
  }
  
  static void recalibrate_floppy(void)
  {

  	debugt(__func__, "");

  	do_floppy = recal_interrupt;
  	output_byte(FD_RECALIBRATE);

  	if (output_byte(UNIT(current_drive)) < 0)

  		reset_fdc();

  }
  
  /*
   * Must do 4 FD_SENSEIs after reset because of ``drive polling''.
   */
  static void reset_interrupt(void)
  {

  	debugt(__func__, "");

  	result();		/* get the status ready for set_fdc */
  	if (FDCS->reset) {

  		pr_info("reset set in interrupt, calling %pf
  ", cont->error);

  		cont->error();	/* a reset just after a reset. BAD! */
  	}
  	cont->redo();
  }
  
  /*
   * reset is done by pulling bit 2 of DOR low for a while (old FDCs),
   * or by setting the self clearing bit 7 of STATUS (newer FDCs)
   */
  static void reset_fdc(void)
  {
  	unsigned long flags;
  
  	do_floppy = reset_interrupt;
  	FDCS->reset = 0;
  	reset_fdc_info(0);
  
  	/* Pseudo-DMA may intercept 'reset finished' interrupt.  */
  	/* Irrelevant for systems with true DMA (i386).          */
  
  	flags = claim_dma_lock();
  	fd_disable_dma();
  	release_dma_lock(flags);
  
  	if (FDCS->version >= FDC_82072A)
  		fd_outb(0x80 | (FDCS->dtr & 3), FD_STATUS);
  	else {
  		fd_outb(FDCS->dor & ~0x04, FD_DOR);
  		udelay(FD_RESET_DELAY);
  		fd_outb(FDCS->dor, FD_DOR);
  	}
  }
  
  static void show_floppy(void)
  {
  	int i;

  	pr_info("
  ");
  	pr_info("floppy driver state
  ");
  	pr_info("-------------------
  ");

  	pr_info("now=%lu last interrupt=%lu diff=%lu last called handler=%pf
  ",

  		jiffies, interruptjiffies, jiffies - interruptjiffies,
  		lasthandler);

  	pr_info("timeout_message=%s
  ", timeout_message);
  	pr_info("last output bytes:
  ");

  	for (i = 0; i < OLOGSIZE; i++)

  		pr_info("%2x %2x %lu
  ",
  			output_log[(i + output_log_pos) % OLOGSIZE].data,
  			output_log[(i + output_log_pos) % OLOGSIZE].status,
  			output_log[(i + output_log_pos) % OLOGSIZE].jiffies);
  	pr_info("last result at %lu
  ", resultjiffies);
  	pr_info("last redo_fd_request at %lu
  ", lastredo);
  	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE, 16, 1,
  		       reply_buffer, resultsize, true);

  	pr_info("status=%x
  ", fd_inb(FD_STATUS));
  	pr_info("fdc_busy=%lu
  ", fdc_busy);

  	if (do_floppy)

  		pr_info("do_floppy=%pf
  ", do_floppy);

  	if (work_pending(&floppy_work))

  		pr_info("floppy_work.func=%pf
  ", floppy_work.func);

  	if (timer_pending(&fd_timer))

  		pr_info("fd_timer.function=%pf
  ", fd_timer.function);

  	if (timer_pending(&fd_timeout)) {

  		pr_info("timer_function=%pf
  ", fd_timeout.function);

  		pr_info("expires=%lu
  ", fd_timeout.expires - jiffies);
  		pr_info("now=%lu
  ", jiffies);
  	}
  	pr_info("cont=%p
  ", cont);
  	pr_info("current_req=%p
  ", current_req);
  	pr_info("command_status=%d
  ", command_status);
  	pr_info("
  ");

  }
  
  static void floppy_shutdown(unsigned long data)
  {
  	unsigned long flags;

  	if (initialized)

  		show_floppy();
  	cancel_activity();
  
  	floppy_enable_hlt();
  
  	flags = claim_dma_lock();
  	fd_disable_dma();
  	release_dma_lock(flags);
  
  	/* avoid dma going to a random drive after shutdown */

  	if (initialized)

  		DPRINT("floppy timeout called
  ");
  	FDCS->reset = 1;
  	if (cont) {
  		cont->done(0);
  		cont->redo();	/* this will recall reset when needed */
  	} else {

  		pr_info("no cont in shutdown!
  ");

  		process_fd_request();
  	}

  	is_alive(__func__, "");

  }

  /* start motor, check media-changed condition and write protection */

  static int start_motor(void (*function)(void))

  {

  	int mask;
  	int data;

  
  	mask = 0xfc;
  	data = UNIT(current_drive);
  	if (!(raw_cmd->flags & FD_RAW_NO_MOTOR)) {
  		if (!(FDCS->dor & (0x10 << UNIT(current_drive)))) {
  			set_debugt();
  			/* no read since this drive is running */
  			DRS->first_read_date = 0;
  			/* note motor start time if motor is not yet running */
  			DRS->spinup_date = jiffies;
  			data |= (0x10 << UNIT(current_drive));
  		}
  	} else if (FDCS->dor & (0x10 << UNIT(current_drive)))
  		mask &= ~(0x10 << UNIT(current_drive));
  
  	/* starts motor and selects floppy */
  	del_timer(motor_off_timer + current_drive);
  	set_dor(fdc, mask, data);
  
  	/* wait_for_completion also schedules reset if needed. */

  	return fd_wait_for_completion(DRS->select_date + DP->select_delay,
  				      (timeout_fn)function);

  }
  
  static void floppy_ready(void)
  {

  	if (FDCS->reset) {
  		reset_fdc();
  		return;
  	}

  	if (start_motor(floppy_ready))
  		return;
  	if (fdc_dtr())
  		return;

  	debug_dcl(DP->flags, "calling disk change from floppy_ready
  ");

  	if (!(raw_cmd->flags & FD_RAW_NO_MOTOR) &&
  	    disk_change(current_drive) && !DP->select_delay)

  		twaddle();	/* this clears the dcl on certain
  				 * drive/controller combinations */

  
  #ifdef fd_chose_dma_mode
  	if ((raw_cmd->flags & FD_RAW_READ) || (raw_cmd->flags & FD_RAW_WRITE)) {
  		unsigned long flags = claim_dma_lock();
  		fd_chose_dma_mode(raw_cmd->kernel_data, raw_cmd->length);
  		release_dma_lock(flags);
  	}
  #endif
  
  	if (raw_cmd->flags & (FD_RAW_NEED_SEEK | FD_RAW_NEED_DISK)) {
  		perpendicular_mode();
  		fdc_specify();	/* must be done here because of hut, hlt ... */
  		seek_floppy();
  	} else {
  		if ((raw_cmd->flags & FD_RAW_READ) ||
  		    (raw_cmd->flags & FD_RAW_WRITE))
  			fdc_specify();
  		setup_rw_floppy();
  	}
  }
  
  static void floppy_start(void)
  {

  	reschedule_timeout(current_reqD, "floppy start");

  
  	scandrives();

  	debug_dcl(DP->flags, "setting NEWCHANGE in floppy_start
  ");

  	set_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags);

  	floppy_ready();
  }
  
  /*
   * ========================================================================
   * here ends the bottom half. Exported routines are:
   * floppy_start, floppy_off, floppy_ready, lock_fdc, unlock_fdc, set_fdc,
   * start_motor, reset_fdc, reset_fdc_info, interpret_errors.
   * Initialization also uses output_byte, result, set_dor, floppy_interrupt
   * and set_dor.
   * ========================================================================
   */
  /*
   * General purpose continuations.
   * ==============================
   */
  
  static void do_wakeup(void)
  {

  	reschedule_timeout(MAXTIMEOUT, "do wakeup");

  	cont = NULL;
  	command_status += 2;
  	wake_up(&command_done);
  }

  static const struct cont_t wakeup_cont = {

  	.interrupt	= empty,
  	.redo		= do_wakeup,
  	.error		= empty,

  	.done		= (done_f)empty

  };

  static const struct cont_t intr_cont = {

  	.interrupt	= empty,
  	.redo		= process_fd_request,
  	.error		= empty,

  	.done		= (done_f)empty

  };

  static int wait_til_done(void (*handler)(void), bool interruptible)

  {
  	int ret;
  
  	schedule_bh(handler);

  	if (interruptible)
  		wait_event_interruptible(command_done, command_status >= 2);
  	else
  		wait_event(command_done, command_status >= 2);

  
  	if (command_status < 2) {
  		cancel_activity();
  		cont = &intr_cont;
  		reset_fdc();
  		return -EINTR;
  	}
  
  	if (FDCS->reset)
  		command_status = FD_COMMAND_ERROR;
  	if (command_status == FD_COMMAND_OKAY)
  		ret = 0;
  	else
  		ret = -EIO;
  	command_status = FD_COMMAND_NONE;
  	return ret;
  }
  
  static void generic_done(int result)
  {
  	command_status = result;
  	cont = &wakeup_cont;
  }
  
  static void generic_success(void)
  {
  	cont->done(1);
  }
  
  static void generic_failure(void)
  {
  	cont->done(0);
  }
  
  static void success_and_wakeup(void)
  {
  	generic_success();
  	cont->redo();
  }
  
  /*
   * formatting and rw support.
   * ==========================
   */
  
  static int next_valid_format(void)
  {
  	int probed_format;
  
  	probed_format = DRS->probed_format;
  	while (1) {
  		if (probed_format >= 8 || !DP->autodetect[probed_format]) {
  			DRS->probed_format = 0;
  			return 1;
  		}
  		if (floppy_type[DP->autodetect[probed_format]].sect) {
  			DRS->probed_format = probed_format;
  			return 0;
  		}
  		probed_format++;
  	}
  }
  
  static void bad_flp_intr(void)
  {
  	int err_count;
  
  	if (probing) {
  		DRS->probed_format++;
  		if (!next_valid_format())
  			return;
  	}
  	err_count = ++(*errors);
  	INFBOUND(DRWE->badness, err_count);
  	if (err_count > DP->max_errors.abort)
  		cont->done(0);
  	if (err_count > DP->max_errors.reset)
  		FDCS->reset = 1;
  	else if (err_count > DP->max_errors.recal)
  		DRS->track = NEED_2_RECAL;
  }
  
  static void set_floppy(int drive)
  {
  	int type = ITYPE(UDRS->fd_device);

  	if (type)
  		_floppy = floppy_type + type;
  	else
  		_floppy = current_type[drive];
  }
  
  /*
   * formatting support.
   * ===================
   */
  static void format_interrupt(void)
  {
  	switch (interpret_errors()) {
  	case 1:
  		cont->error();
  	case 2:
  		break;
  	case 0:
  		cont->done(1);
  	}
  	cont->redo();
  }

  #define FM_MODE(x, y) ((y) & ~(((x)->rate & 0x80) >> 1))

  #define CT(x) ((x) | 0xc0)

  static void setup_format_params(int track)
  {

  	int n;
  	int il;
  	int count;
  	int head_shift;
  	int track_shift;

  	struct fparm {
  		unsigned char track, head, sect, size;
  	} *here = (struct fparm *)floppy_track_buffer;

  
  	raw_cmd = &default_raw_cmd;
  	raw_cmd->track = track;

  	raw_cmd->flags = (FD_RAW_WRITE | FD_RAW_INTR | FD_RAW_SPIN |
  			  FD_RAW_NEED_DISK | FD_RAW_NEED_SEEK);

  	raw_cmd->rate = _floppy->rate & 0x43;
  	raw_cmd->cmd_count = NR_F;
  	COMMAND = FM_MODE(_floppy, FD_FORMAT);
  	DR_SELECT = UNIT(current_drive) + PH_HEAD(_floppy, format_req.head);
  	F_SIZECODE = FD_SIZECODE(_floppy);
  	F_SECT_PER_TRACK = _floppy->sect << 2 >> F_SIZECODE;
  	F_GAP = _floppy->fmt_gap;
  	F_FILL = FD_FILL_BYTE;
  
  	raw_cmd->kernel_data = floppy_track_buffer;
  	raw_cmd->length = 4 * F_SECT_PER_TRACK;
  
  	/* allow for about 30ms for data transport per track */
  	head_shift = (F_SECT_PER_TRACK + 5) / 6;
  
  	/* a ``cylinder'' is two tracks plus a little stepping time */
  	track_shift = 2 * head_shift + 3;
  
  	/* position of logical sector 1 on this track */
  	n = (track_shift * format_req.track + head_shift * format_req.head)
  	    % F_SECT_PER_TRACK;
  
  	/* determine interleave */
  	il = 1;
  	if (_floppy->fmt_gap < 0x22)
  		il++;
  
  	/* initialize field */
  	for (count = 0; count < F_SECT_PER_TRACK; ++count) {
  		here[count].track = format_req.track;
  		here[count].head = format_req.head;
  		here[count].sect = 0;
  		here[count].size = F_SIZECODE;
  	}
  	/* place logical sectors */
  	for (count = 1; count <= F_SECT_PER_TRACK; ++count) {
  		here[n].sect = count;
  		n = (n + il) % F_SECT_PER_TRACK;
  		if (here[n].sect) {	/* sector busy, find next free sector */
  			++n;
  			if (n >= F_SECT_PER_TRACK) {
  				n -= F_SECT_PER_TRACK;
  				while (here[n].sect)
  					++n;
  			}
  		}
  	}

  	if (_floppy->stretch & FD_SECTBASEMASK) {

  		for (count = 0; count < F_SECT_PER_TRACK; count++)

  			here[count].sect += FD_SECTBASE(_floppy) - 1;

  	}
  }
  
  static void redo_format(void)
  {
  	buffer_track = -1;
  	setup_format_params(format_req.track << STRETCH(_floppy));
  	floppy_start();

  	debugt(__func__, "queue format request");

  }

  static const struct cont_t format_cont = {

  	.interrupt	= format_interrupt,
  	.redo		= redo_format,
  	.error		= bad_flp_intr,
  	.done		= generic_done
  };
  
  static int do_format(int drive, struct format_descr *tmp_format_req)
  {
  	int ret;

  	if (lock_fdc(drive, true))

  		return -EINTR;

  	set_floppy(drive);
  	if (!_floppy ||
  	    _floppy->track > DP->tracks ||
  	    tmp_format_req->track >= _floppy->track ||
  	    tmp_format_req->head >= _floppy->head ||
  	    (_floppy->sect << 2) % (1 << FD_SIZECODE(_floppy)) ||
  	    !_floppy->fmt_gap) {
  		process_fd_request();
  		return -EINVAL;
  	}
  	format_req = *tmp_format_req;
  	format_errors = 0;
  	cont = &format_cont;
  	errors = &format_errors;

  	ret = wait_til_done(redo_format, true);

  	if (ret == -EINTR)
  		return -EINTR;

  	process_fd_request();
  	return ret;
  }
  
  /*
   * Buffer read/write and support
   * =============================
   */

  static void floppy_end_request(struct request *req, int error)

  {
  	unsigned int nr_sectors = current_count_sectors;

  	unsigned int drive = (unsigned long)req->rq_disk->private_data;

  
  	/* current_count_sectors can be zero if transfer failed */

  	if (error)

  		nr_sectors = blk_rq_cur_sectors(req);

  	if (__blk_end_request(req, error, nr_sectors << 9))

  		return;

  
  	/* We're done with the request */

  	floppy_off(drive);

  	current_req = NULL;
  }
  
  /* new request_done. Can handle physical sectors which are smaller than a
   * logical buffer */
  static void request_done(int uptodate)
  {

  	struct request *req = current_req;

  	struct request_queue *q;

  	unsigned long flags;
  	int block;

  	char msg[sizeof("request done ") + sizeof(int) * 3];

  
  	probing = 0;

  	snprintf(msg, sizeof(msg), "request done %d", uptodate);
  	reschedule_timeout(MAXTIMEOUT, msg);

  
  	if (!req) {

  		pr_info("floppy.c: no request in request_done
  ");

  		return;
  	}

  	q = req->q;

  	if (uptodate) {
  		/* maintain values for invalidation on geometry
  		 * change */

  		block = current_count_sectors + blk_rq_pos(req);

  		INFBOUND(DRS->maxblock, block);
  		if (block > _floppy->sect)
  			DRS->maxtrack = 1;
  
  		/* unlock chained buffers */
  		spin_lock_irqsave(q->queue_lock, flags);

  		floppy_end_request(req, 0);

  		spin_unlock_irqrestore(q->queue_lock, flags);
  	} else {
  		if (rq_data_dir(req) == WRITE) {
  			/* record write error information */
  			DRWE->write_errors++;
  			if (DRWE->write_errors == 1) {

  				DRWE->first_error_sector = blk_rq_pos(req);

  				DRWE->first_error_generation = DRS->generation;
  			}

  			DRWE->last_error_sector = blk_rq_pos(req);

  			DRWE->last_error_generation = DRS->generation;
  		}
  		spin_lock_irqsave(q->queue_lock, flags);

  		floppy_end_request(req, -EIO);

  		spin_unlock_irqrestore(q->queue_lock, flags);
  	}
  }
  
  /* Interrupt handler evaluating the result of the r/w operation */
  static void rw_interrupt(void)
  {

  	int eoc;
  	int ssize;
  	int heads;
  	int nr_sectors;

  
  	if (R_HEAD >= 2) {
  		/* some Toshiba floppy controllers occasionnally seem to
  		 * return bogus interrupts after read/write operations, which
  		 * can be recognized by a bad head number (>= 2) */
  		return;
  	}
  
  	if (!DRS->first_read_date)
  		DRS->first_read_date = jiffies;
  
  	nr_sectors = 0;

  	ssize = DIV_ROUND_UP(1 << SIZECODE, 4);

  
  	if (ST1 & ST1_EOC)
  		eoc = 1;
  	else
  		eoc = 0;
  
  	if (COMMAND & 0x80)
  		heads = 2;
  	else
  		heads = 1;
  
  	nr_sectors = (((R_TRACK - TRACK) * heads +
  		       R_HEAD - HEAD) * SECT_PER_TRACK +
  		      R_SECTOR - SECTOR + eoc) << SIZECODE >> 2;

  	if (nr_sectors / ssize >

  	    DIV_ROUND_UP(in_sector_offset + current_count_sectors, ssize)) {

  		DPRINT("long rw: %x instead of %lx
  ",
  		       nr_sectors, current_count_sectors);

  		pr_info("rs=%d s=%d
  ", R_SECTOR, SECTOR);
  		pr_info("rh=%d h=%d
  ", R_HEAD, HEAD);
  		pr_info("rt=%d t=%d
  ", R_TRACK, TRACK);
  		pr_info("heads=%d eoc=%d
  ", heads, eoc);
  		pr_info("spt=%d st=%d ss=%d
  ",
  			SECT_PER_TRACK, fsector_t, ssize);
  		pr_info("in_sector_offset=%d
  ", in_sector_offset);

  	}

  
  	nr_sectors -= in_sector_offset;
  	INFBOUND(nr_sectors, 0);
  	SUPBOUND(current_count_sectors, nr_sectors);
  
  	switch (interpret_errors()) {
  	case 2:
  		cont->redo();
  		return;
  	case 1:
  		if (!current_count_sectors) {
  			cont->error();
  			cont->redo();
  			return;
  		}
  		break;
  	case 0:
  		if (!current_count_sectors) {
  			cont->redo();
  			return;
  		}
  		current_type[current_drive] = _floppy;
  		floppy_sizes[TOMINOR(current_drive)] = _floppy->size;
  		break;
  	}
  
  	if (probing) {
  		if (DP->flags & FTD_MSG)
  			DPRINT("Auto-detected floppy type %s in fd%d
  ",
  			       _floppy->name, current_drive);
  		current_type[current_drive] = _floppy;
  		floppy_sizes[TOMINOR(current_drive)] = _floppy->size;
  		probing = 0;
  	}
  
  	if (CT(COMMAND) != FD_READ ||
  	    raw_cmd->kernel_data == current_req->buffer) {
  		/* transfer directly from buffer */
  		cont->done(1);
  	} else if (CT(COMMAND) == FD_READ) {
  		buffer_track = raw_cmd->track;
  		buffer_drive = current_drive;
  		INFBOUND(buffer_max, nr_sectors + fsector_t);
  	}
  	cont->redo();
  }
  
  /* Compute maximal contiguous buffer size. */
  static int buffer_chain_size(void)
  {

  	struct bio_vec *bv;

  	int size;
  	struct req_iterator iter;

  	char *base;
  
  	base = bio_data(current_req->bio);
  	size = 0;

  	rq_for_each_segment(bv, current_req, iter) {
  		if (page_address(bv->bv_page) + bv->bv_offset != base + size)
  			break;

  		size += bv->bv_len;

  	}
  
  	return size >> 9;
  }
  
  /* Compute the maximal transfer size */
  static int transfer_size(int ssize, int max_sector, int max_size)
  {
  	SUPBOUND(max_sector, fsector_t + max_size);
  
  	/* alignment */
  	max_sector -= (max_sector % _floppy->sect) % ssize;
  
  	/* transfer size, beginning not aligned */
  	current_count_sectors = max_sector - fsector_t;
  
  	return max_sector;
  }
  
  /*
   * Move data from/to the track buffer to/from the buffer cache.
   */
  static void copy_buffer(int ssize, int max_sector, int max_sector_2)
  {
  	int remaining;		/* number of transferred 512-byte sectors */
  	struct bio_vec *bv;

  	char *buffer;
  	char *dma_buffer;

  	int size;
  	struct req_iterator iter;

  
  	max_sector = transfer_size(ssize,
  				   min(max_sector, max_sector_2),

  				   blk_rq_sectors(current_req));

  
  	if (current_count_sectors <= 0 && CT(COMMAND) == FD_WRITE &&

  	    buffer_max > fsector_t + blk_rq_sectors(current_req))

  		current_count_sectors = min_t(int, buffer_max - fsector_t,

  					      blk_rq_sectors(current_req));

  
  	remaining = current_count_sectors << 9;

  	if (remaining > blk_rq_bytes(current_req) && CT(COMMAND) == FD_WRITE) {

  		DPRINT("in copy buffer
  ");

  		pr_info("current_count_sectors=%ld
  ", current_count_sectors);
  		pr_info("remaining=%d
  ", remaining >> 9);
  		pr_info("current_req->nr_sectors=%u
  ",
  			blk_rq_sectors(current_req));
  		pr_info("current_req->current_nr_sectors=%u
  ",
  			blk_rq_cur_sectors(current_req));
  		pr_info("max_sector=%d
  ", max_sector);
  		pr_info("ssize=%d
  ", ssize);

  	}

  
  	buffer_max = max(max_sector, buffer_max);
  
  	dma_buffer = floppy_track_buffer + ((fsector_t - buffer_min) << 9);

  	size = blk_rq_cur_bytes(current_req);

  	rq_for_each_segment(bv, current_req, iter) {
  		if (!remaining)
  			break;

  		size = bv->bv_len;
  		SUPBOUND(size, remaining);

  		buffer = page_address(bv->bv_page) + bv->bv_offset;

  		if (dma_buffer + size >
  		    floppy_track_buffer + (max_buffer_sectors << 10) ||
  		    dma_buffer < floppy_track_buffer) {
  			DPRINT("buffer overrun in copy buffer %d
  ",

  			       (int)((floppy_track_buffer - dma_buffer) >> 9));
  			pr_info("fsector_t=%d buffer_min=%d
  ",
  				fsector_t, buffer_min);
  			pr_info("current_count_sectors=%ld
  ",
  				current_count_sectors);

  			if (CT(COMMAND) == FD_READ)

  				pr_info("read
  ");

  			if (CT(COMMAND) == FD_WRITE)

  				pr_info("write
  ");

  			break;

  		}

  		if (((unsigned long)buffer) % 512)
  			DPRINT("%p buffer not aligned
  ", buffer);

  		if (CT(COMMAND) == FD_READ)
  			memcpy(buffer, dma_buffer, size);
  		else
  			memcpy(dma_buffer, buffer, size);
  
  		remaining -= size;
  		dma_buffer += size;

  	}

  	if (remaining) {
  		if (remaining > 0)
  			max_sector -= remaining >> 9;
  		DPRINT("weirdness: remaining %d
  ", remaining >> 9);
  	}

  }

  /* work around a bug in pseudo DMA
   * (on some FDCs) pseudo DMA does not stop when the CPU stops
   * sending data.  Hence we need a different way to signal the
   * transfer length:  We use SECT_PER_TRACK.  Unfortunately, this
   * does not work with MT, hence we can only transfer one head at
   * a time
   */
  static void virtualdmabug_workaround(void)
  {

  	int hard_sectors;
  	int end_sector;

  
  	if (CT(COMMAND) == FD_WRITE) {
  		COMMAND &= ~0x80;	/* switch off multiple track mode */
  
  		hard_sectors = raw_cmd->length >> (7 + SIZECODE);
  		end_sector = SECTOR + hard_sectors - 1;

  		if (end_sector > SECT_PER_TRACK) {

  			pr_info("too many sectors %d > %d
  ",
  				end_sector, SECT_PER_TRACK);

  			return;
  		}

  		SECT_PER_TRACK = end_sector;
  					/* make sure SECT_PER_TRACK
  					 * points to end of transfer */

  	}
  }
  
  /*
   * Formulate a read/write request.
   * this routine decides where to load the data (directly to buffer, or to
   * tmp floppy area), how much data to load (the size of the buffer, the whole
   * track, or a single sector)
   * All floppy_track_buffer handling goes in here. If we ever add track buffer
   * allocation on the fly, it should be done here. No other part should need
   * modification.
   */
  
  static int make_raw_rw_request(void)
  {
  	int aligned_sector_t;

  	int max_sector;
  	int max_size;
  	int tracksize;
  	int ssize;

  	if (WARN(max_buffer_sectors == 0, "VFS: Block I/O scheduled on unopened device
  "))

  		return 0;

  
  	set_fdc((long)current_req->rq_disk->private_data);
  
  	raw_cmd = &default_raw_cmd;
  	raw_cmd->flags = FD_RAW_SPIN | FD_RAW_NEED_DISK | FD_RAW_NEED_DISK |
  	    FD_RAW_NEED_SEEK;
  	raw_cmd->cmd_count = NR_RW;
  	if (rq_data_dir(current_req) == READ) {
  		raw_cmd->flags |= FD_RAW_READ;
  		COMMAND = FM_MODE(_floppy, FD_READ);
  	} else if (rq_data_dir(current_req) == WRITE) {
  		raw_cmd->flags |= FD_RAW_WRITE;
  		COMMAND = FM_MODE(_floppy, FD_WRITE);
  	} else {

  		DPRINT("%s: unknown command
  ", __func__);

  		return 0;
  	}
  
  	max_sector = _floppy->sect * _floppy->head;

  	TRACK = (int)blk_rq_pos(current_req) / max_sector;
  	fsector_t = (int)blk_rq_pos(current_req) % max_sector;

  	if (_floppy->track && TRACK >= _floppy->track) {

  		if (blk_rq_cur_sectors(current_req) & 1) {

  			current_count_sectors = 1;
  			return 1;
  		} else
  			return 0;
  	}
  	HEAD = fsector_t / _floppy->sect;

  	if (((_floppy->stretch & (FD_SWAPSIDES | FD_SECTBASEMASK)) ||

  	     test_bit(FD_NEED_TWADDLE_BIT, &DRS->flags)) &&
  	    fsector_t < _floppy->sect)

  		max_sector = _floppy->sect;
  
  	/* 2M disks have phantom sectors on the first track */
  	if ((_floppy->rate & FD_2M) && (!TRACK) && (!HEAD)) {
  		max_sector = 2 * _floppy->sect / 3;
  		if (fsector_t >= max_sector) {
  			current_count_sectors =
  			    min_t(int, _floppy->sect - fsector_t,

  				  blk_rq_sectors(current_req));

  			return 1;
  		}
  		SIZECODE = 2;
  	} else
  		SIZECODE = FD_SIZECODE(_floppy);
  	raw_cmd->rate = _floppy->rate & 0x43;
  	if ((_floppy->rate & FD_2M) && (TRACK || HEAD) && raw_cmd->rate == 2)
  		raw_cmd->rate = 1;
  
  	if (SIZECODE)
  		SIZECODE2 = 0xff;
  	else
  		SIZECODE2 = 0x80;
  	raw_cmd->track = TRACK << STRETCH(_floppy);
  	DR_SELECT = UNIT(current_drive) + PH_HEAD(_floppy, HEAD);
  	GAP = _floppy->gap;

  	ssize = DIV_ROUND_UP(1 << SIZECODE, 4);

  	SECT_PER_TRACK = _floppy->sect << 2 >> SIZECODE;
  	SECTOR = ((fsector_t % _floppy->sect) << 2 >> SIZECODE) +

  	    FD_SECTBASE(_floppy);

  
  	/* tracksize describes the size which can be filled up with sectors
  	 * of size ssize.
  	 */
  	tracksize = _floppy->sect - _floppy->sect % ssize;
  	if (tracksize < _floppy->sect) {
  		SECT_PER_TRACK++;
  		if (tracksize <= fsector_t % _floppy->sect)
  			SECTOR--;
  
  		/* if we are beyond tracksize, fill up using smaller sectors */
  		while (tracksize <= fsector_t % _floppy->sect) {
  			while (tracksize + ssize > _floppy->sect) {
  				SIZECODE--;
  				ssize >>= 1;
  			}
  			SECTOR++;
  			SECT_PER_TRACK++;
  			tracksize += ssize;
  		}
  		max_sector = HEAD * _floppy->sect + tracksize;
  	} else if (!TRACK && !HEAD && !(_floppy->rate & FD_2M) && probing) {
  		max_sector = _floppy->sect;
  	} else if (!HEAD && CT(COMMAND) == FD_WRITE) {
  		/* for virtual DMA bug workaround */
  		max_sector = _floppy->sect;
  	}
  
  	in_sector_offset = (fsector_t % _floppy->sect) % ssize;
  	aligned_sector_t = fsector_t - in_sector_offset;

  	max_size = blk_rq_sectors(current_req);

  	if ((raw_cmd->track == buffer_track) &&
  	    (current_drive == buffer_drive) &&
  	    (fsector_t >= buffer_min) && (fsector_t < buffer_max)) {
  		/* data already in track buffer */
  		if (CT(COMMAND) == FD_READ) {
  			copy_buffer(1, max_sector, buffer_max);
  			return 1;
  		}

  	} else if (in_sector_offset || blk_rq_sectors(current_req) < ssize) {

  		if (CT(COMMAND) == FD_WRITE) {

  			unsigned int sectors;
  
  			sectors = fsector_t + blk_rq_sectors(current_req);
  			if (sectors > ssize && sectors < ssize + ssize)

  				max_size = ssize + ssize;
  			else
  				max_size = ssize;
  		}
  		raw_cmd->flags &= ~FD_RAW_WRITE;
  		raw_cmd->flags |= FD_RAW_READ;
  		COMMAND = FM_MODE(_floppy, FD_READ);
  	} else if ((unsigned long)current_req->buffer < MAX_DMA_ADDRESS) {
  		unsigned long dma_limit;
  		int direct, indirect;
  
  		indirect =
  		    transfer_size(ssize, max_sector,
  				  max_buffer_sectors * 2) - fsector_t;
  
  		/*
  		 * Do NOT use minimum() here---MAX_DMA_ADDRESS is 64 bits wide
  		 * on a 64 bit machine!
  		 */
  		max_size = buffer_chain_size();

  		dma_limit = (MAX_DMA_ADDRESS -
  			     ((unsigned long)current_req->buffer)) >> 9;

  		if ((unsigned long)max_size > dma_limit)

  			max_size = dma_limit;

  		/* 64 kb boundaries */
  		if (CROSS_64KB(current_req->buffer, max_size << 9))
  			max_size = (K_64 -
  				    ((unsigned long)current_req->buffer) %
  				    K_64) >> 9;
  		direct = transfer_size(ssize, max_sector, max_size) - fsector_t;
  		/*
  		 * We try to read tracks, but if we get too many errors, we
  		 * go back to reading just one sector at a time.
  		 *
  		 * This means we should be able to read a sector even if there
  		 * are other bad sectors on this track.
  		 */
  		if (!direct ||
  		    (indirect * 2 > direct * 3 &&

  		     *errors < DP->max_errors.read_track &&
  		     ((!probing ||
  		       (DP->read_track & (1 << DRS->probed_format)))))) {

  			max_size = blk_rq_sectors(current_req);

  		} else {
  			raw_cmd->kernel_data = current_req->buffer;
  			raw_cmd->length = current_count_sectors << 9;
  			if (raw_cmd->length == 0) {

  				DPRINT("%s: zero dma transfer attempted
  ", __func__);

  				DPRINT("indirect=%d direct=%d fsector_t=%d
  ",

  				       indirect, direct, fsector_t);
  				return 0;
  			}

  			virtualdmabug_workaround();
  			return 2;
  		}
  	}
  
  	if (CT(COMMAND) == FD_READ)
  		max_size = max_sector;	/* unbounded */
  
  	/* claim buffer track if needed */
  	if (buffer_track != raw_cmd->track ||	/* bad track */
  	    buffer_drive != current_drive ||	/* bad drive */
  	    fsector_t > buffer_max ||
  	    fsector_t < buffer_min ||
  	    ((CT(COMMAND) == FD_READ ||

  	      (!in_sector_offset && blk_rq_sectors(current_req) >= ssize)) &&

  	     max_sector > 2 * max_buffer_sectors + buffer_min &&

  	     max_size + fsector_t > 2 * max_buffer_sectors + buffer_min)) {
  		/* not enough space */

  		buffer_track = -1;
  		buffer_drive = current_drive;
  		buffer_max = buffer_min = aligned_sector_t;
  	}
  	raw_cmd->kernel_data = floppy_track_buffer +

  		((aligned_sector_t - buffer_min) << 9);

  
  	if (CT(COMMAND) == FD_WRITE) {
  		/* copy write buffer to track buffer.
  		 * if we get here, we know that the write
  		 * is either aligned or the data already in the buffer
  		 * (buffer will be overwritten) */

  		if (in_sector_offset && buffer_track == -1)
  			DPRINT("internal error offset !=0 on write
  ");

  		buffer_track = raw_cmd->track;
  		buffer_drive = current_drive;
  		copy_buffer(ssize, max_sector,
  			    2 * max_buffer_sectors + buffer_min);
  	} else
  		transfer_size(ssize, max_sector,
  			      2 * max_buffer_sectors + buffer_min -
  			      aligned_sector_t);
  
  	/* round up current_count_sectors to get dma xfer size */
  	raw_cmd->length = in_sector_offset + current_count_sectors;
  	raw_cmd->length = ((raw_cmd->length - 1) | (ssize - 1)) + 1;
  	raw_cmd->length <<= 9;

  	if ((raw_cmd->length < current_count_sectors << 9) ||
  	    (raw_cmd->kernel_data != current_req->buffer &&
  	     CT(COMMAND) == FD_WRITE &&
  	     (aligned_sector_t + (raw_cmd->length >> 9) > buffer_max ||
  	      aligned_sector_t < buffer_min)) ||
  	    raw_cmd->length % (128 << SIZECODE) ||
  	    raw_cmd->length <= 0 || current_count_sectors <= 0) {
  		DPRINT("fractionary current count b=%lx s=%lx
  ",
  		       raw_cmd->length, current_count_sectors);
  		if (raw_cmd->kernel_data != current_req->buffer)

  			pr_info("addr=%d, length=%ld
  ",
  				(int)((raw_cmd->kernel_data -
  				       floppy_track_buffer) >> 9),
  				current_count_sectors);
  		pr_info("st=%d ast=%d mse=%d msi=%d
  ",
  			fsector_t, aligned_sector_t, max_sector, max_size);
  		pr_info("ssize=%x SIZECODE=%d
  ", ssize, SIZECODE);
  		pr_info("command=%x SECTOR=%d HEAD=%d, TRACK=%d
  ",
  			COMMAND, SECTOR, HEAD, TRACK);
  		pr_info("buffer drive=%d
  ", buffer_drive);
  		pr_info("buffer track=%d
  ", buffer_track);
  		pr_info("buffer_min=%d
  ", buffer_min);
  		pr_info("buffer_max=%d
  ", buffer_max);

  		return 0;
  	}
  
  	if (raw_cmd->kernel_data != current_req->buffer) {
  		if (raw_cmd->kernel_data < floppy_track_buffer ||
  		    current_count_sectors < 0 ||
  		    raw_cmd->length < 0 ||
  		    raw_cmd->kernel_data + raw_cmd->length >
  		    floppy_track_buffer + (max_buffer_sectors << 10)) {
  			DPRINT("buffer overrun in schedule dma
  ");

  			pr_info("fsector_t=%d buffer_min=%d current_count=%ld
  ",
  				fsector_t, buffer_min, raw_cmd->length >> 9);
  			pr_info("current_count_sectors=%ld
  ",
  				current_count_sectors);

  			if (CT(COMMAND) == FD_READ)

  				pr_info("read
  ");

  			if (CT(COMMAND) == FD_WRITE)

  				pr_info("write
  ");

  			return 0;
  		}

  	} else if (raw_cmd->length > blk_rq_bytes(current_req) ||

  		   current_count_sectors > blk_rq_sectors(current_req)) {

  		DPRINT("buffer overrun in direct transfer
  ");
  		return 0;
  	} else if (raw_cmd->length < current_count_sectors << 9) {
  		DPRINT("more sectors than bytes
  ");

  		pr_info("bytes=%ld
  ", raw_cmd->length >> 9);
  		pr_info("sectors=%ld
  ", current_count_sectors);

  	}
  	if (raw_cmd->length == 0) {
  		DPRINT("zero dma transfer attempted from make_raw_request
  ");
  		return 0;
  	}

  
  	virtualdmabug_workaround();
  	return 2;
  }

  /*
   * Round-robin between our available drives, doing one request from each
   */
  static int set_next_request(void)
  {
  	struct request_queue *q;
  	int old_pos = fdc_queue;
  
  	do {
  		q = disks[fdc_queue]->queue;
  		if (++fdc_queue == N_DRIVE)
  			fdc_queue = 0;
  		if (q) {
  			current_req = blk_fetch_request(q);
  			if (current_req)
  				break;
  		}
  	} while (fdc_queue != old_pos);
  
  	return current_req != NULL;
  }

  static void redo_fd_request(void)
  {

  	int drive;
  	int tmp;
  
  	lastredo = jiffies;
  	if (current_drive < N_DRIVE)
  		floppy_off(current_drive);

  do_request:
  	if (!current_req) {

  		int pending;
  
  		spin_lock_irq(&floppy_lock);
  		pending = set_next_request();
  		spin_unlock_irq(&floppy_lock);

  		if (!pending) {

  			do_floppy = NULL;
  			unlock_fdc();

  			return;

  		}

  	}
  	drive = (long)current_req->rq_disk->private_data;
  	set_fdc(drive);

  	reschedule_timeout(current_reqD, "redo fd request");

  	set_floppy(drive);
  	raw_cmd = &default_raw_cmd;
  	raw_cmd->flags = 0;
  	if (start_motor(redo_fd_request))

  		return;

  
  	disk_change(current_drive);
  	if (test_bit(current_drive, &fake_change) ||
  	    test_bit(FD_DISK_CHANGED_BIT, &DRS->flags)) {
  		DPRINT("disk absent or changed during operation
  ");
  		request_done(0);
  		goto do_request;
  	}
  	if (!_floppy) {	/* Autodetection */
  		if (!probing) {
  			DRS->probed_format = 0;
  			if (next_valid_format()) {
  				DPRINT("no autodetectable formats
  ");
  				_floppy = NULL;
  				request_done(0);
  				goto do_request;
  			}
  		}
  		probing = 1;
  		_floppy = floppy_type + DP->autodetect[DRS->probed_format];
  	} else
  		probing = 0;
  	errors = &(current_req->errors);
  	tmp = make_raw_rw_request();
  	if (tmp < 2) {
  		request_done(tmp);
  		goto do_request;

  	}

  
  	if (test_bit(FD_NEED_TWADDLE_BIT, &DRS->flags))
  		twaddle();
  	schedule_bh(floppy_start);

  	debugt(__func__, "queue fd request");

  	return;

  }

  static const struct cont_t rw_cont = {

  	.interrupt	= rw_interrupt,
  	.redo		= redo_fd_request,
  	.error		= bad_flp_intr,
  	.done		= request_done
  };
  
  static void process_fd_request(void)
  {
  	cont = &rw_cont;
  	schedule_bh(redo_fd_request);
  }

  static void do_fd_request(struct request_queue *q)

  {

  	if (WARN(max_buffer_sectors == 0,
  		 "VFS: %s called on non-open device
  ", __func__))

  		return;

  	if (WARN(atomic_read(&usage_count) == 0,
  		 "warning: usage count=0, current_req=%p sect=%ld type=%x flags=%x
  ",
  		 current_req, (long)blk_rq_pos(current_req), current_req->cmd_type,
  		 current_req->cmd_flags))

  		return;

  	if (test_bit(0, &fdc_busy)) {
  		/* fdc busy, this new request will be treated when the
  		   current one is done */

  		is_alive(__func__, "old request running");

  		return;
  	}

  	lock_fdc(MAXTIMEOUT, false);

  	process_fd_request();

  	is_alive(__func__, "");

  }

  static const struct cont_t poll_cont = {

  	.interrupt	= success_and_wakeup,
  	.redo		= floppy_ready,
  	.error		= generic_failure,
  	.done		= generic_done
  };

  static int poll_drive(bool interruptible, int flag)

  {

  	/* no auto-sense, just clear dcl */
  	raw_cmd = &default_raw_cmd;
  	raw_cmd->flags = flag;
  	raw_cmd->track = 0;
  	raw_cmd->cmd_count = 0;
  	cont = &poll_cont;

  	debug_dcl(DP->flags, "setting NEWCHANGE in poll_drive
  ");

  	set_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags);

  
  	return wait_til_done(floppy_ready, interruptible);

  }
  
  /*
   * User triggered reset
   * ====================
   */
  
  static void reset_intr(void)
  {

  	pr_info("weird, reset interrupt called
  ");

  }

  static const struct cont_t reset_cont = {

  	.interrupt	= reset_intr,
  	.redo		= success_and_wakeup,
  	.error		= generic_failure,
  	.done		= generic_done
  };

  static int user_reset_fdc(int drive, int arg, bool interruptible)

  {
  	int ret;

  	if (lock_fdc(drive, interruptible))
  		return -EINTR;

  	if (arg == FD_RESET_ALWAYS)
  		FDCS->reset = 1;
  	if (FDCS->reset) {
  		cont = &reset_cont;

  		ret = wait_til_done(reset_fdc, interruptible);
  		if (ret == -EINTR)
  			return -EINTR;

  	}
  	process_fd_request();

  	return 0;

  }
  
  /*
   * Misc Ioctl's and support
   * ========================
   */
  static inline int fd_copyout(void __user *param, const void *address,
  			     unsigned long size)
  {
  	return copy_to_user(param, address, size) ? -EFAULT : 0;
  }

  static inline int fd_copyin(void __user *param, void *address,
  			    unsigned long size)

  {
  	return copy_from_user(address, param, size) ? -EFAULT : 0;
  }

  static const char *drive_name(int type, int drive)

  {
  	struct floppy_struct *floppy;
  
  	if (type)
  		floppy = floppy_type + type;
  	else {
  		if (UDP->native_format)
  			floppy = floppy_type + UDP->native_format;
  		else
  			return "(null)";
  	}
  	if (floppy->name)
  		return floppy->name;
  	else
  		return "(null)";
  }
  
  /* raw commands */
  static void raw_cmd_done(int flag)
  {
  	int i;
  
  	if (!flag) {
  		raw_cmd->flags |= FD_RAW_FAILURE;
  		raw_cmd->flags |= FD_RAW_HARDFAILURE;
  	} else {
  		raw_cmd->reply_count = inr;
  		if (raw_cmd->reply_count > MAX_REPLIES)
  			raw_cmd->reply_count = 0;
  		for (i = 0; i < raw_cmd->reply_count; i++)
  			raw_cmd->reply[i] = reply_buffer[i];
  
  		if (raw_cmd->flags & (FD_RAW_READ | FD_RAW_WRITE)) {
  			unsigned long flags;
  			flags = claim_dma_lock();
  			raw_cmd->length = fd_get_dma_residue();
  			release_dma_lock(flags);
  		}
  
  		if ((raw_cmd->flags & FD_RAW_SOFTFAILURE) &&
  		    (!raw_cmd->reply_count || (raw_cmd->reply[0] & 0xc0)))
  			raw_cmd->flags |= FD_RAW_FAILURE;
  
  		if (disk_change(current_drive))
  			raw_cmd->flags |= FD_RAW_DISK_CHANGE;
  		else
  			raw_cmd->flags &= ~FD_RAW_DISK_CHANGE;
  		if (raw_cmd->flags & FD_RAW_NO_MOTOR_AFTER)
  			motor_off_callback(current_drive);
  
  		if (raw_cmd->next &&
  		    (!(raw_cmd->flags & FD_RAW_FAILURE) ||
  		     !(raw_cmd->flags & FD_RAW_STOP_IF_FAILURE)) &&
  		    ((raw_cmd->flags & FD_RAW_FAILURE) ||
  		     !(raw_cmd->flags & FD_RAW_STOP_IF_SUCCESS))) {
  			raw_cmd = raw_cmd->next;
  			return;
  		}
  	}
  	generic_done(flag);
  }

  static const struct cont_t raw_cmd_cont = {

  	.interrupt	= success_and_wakeup,
  	.redo		= floppy_start,
  	.error		= generic_failure,
  	.done		= raw_cmd_done
  };

  static int raw_cmd_copyout(int cmd, void __user *param,

  				  struct floppy_raw_cmd *ptr)
  {
  	int ret;
  
  	while (ptr) {

  		ret = copy_to_user(param, ptr, sizeof(*ptr));

  		if (ret)
  			return -EFAULT;

  		param += sizeof(struct floppy_raw_cmd);
  		if ((ptr->flags & FD_RAW_READ) && ptr->buffer_length) {

  			if (ptr->length >= 0 &&
  			    ptr->length <= ptr->buffer_length) {
  				long length = ptr->buffer_length - ptr->length;

  				ret = fd_copyout(ptr->data, ptr->kernel_data,
  						 length);
  				if (ret)
  					return ret;

  			}

  		}
  		ptr = ptr->next;
  	}

  	return 0;
  }
  
  static void raw_cmd_free(struct floppy_raw_cmd **ptr)
  {

  	struct floppy_raw_cmd *next;
  	struct floppy_raw_cmd *this;

  
  	this = *ptr;
  	*ptr = NULL;
  	while (this) {
  		if (this->buffer_length) {
  			fd_dma_mem_free((unsigned long)this->kernel_data,
  					this->buffer_length);
  			this->buffer_length = 0;
  		}
  		next = this->next;
  		kfree(this);
  		this = next;
  	}
  }

  static int raw_cmd_copyin(int cmd, void __user *param,

  				 struct floppy_raw_cmd **rcmd)
  {
  	struct floppy_raw_cmd *ptr;
  	int ret;
  	int i;
  
  	*rcmd = NULL;

  
  loop:
  	ptr = kmalloc(sizeof(struct floppy_raw_cmd), GFP_USER);
  	if (!ptr)
  		return -ENOMEM;
  	*rcmd = ptr;
  	ret = copy_from_user(ptr, param, sizeof(*ptr));
  	if (ret)
  		return -EFAULT;
  	ptr->next = NULL;
  	ptr->buffer_length = 0;
  	param += sizeof(struct floppy_raw_cmd);
  	if (ptr->cmd_count > 33)

  			/* the command may now also take up the space
  			 * initially intended for the reply & the
  			 * reply count. Needed for long 82078 commands
  			 * such as RESTORE, which takes ... 17 command
  			 * bytes. Murphy's law #137: When you reserve
  			 * 16 bytes for a structure, you'll one day
  			 * discover that you really need 17...
  			 */

  		return -EINVAL;
  
  	for (i = 0; i < 16; i++)
  		ptr->reply[i] = 0;
  	ptr->resultcode = 0;
  	ptr->kernel_data = NULL;
  
  	if (ptr->flags & (FD_RAW_READ | FD_RAW_WRITE)) {
  		if (ptr->length <= 0)

  			return -EINVAL;

  		ptr->kernel_data = (char *)fd_dma_mem_alloc(ptr->length);
  		fallback_on_nodma_alloc(&ptr->kernel_data, ptr->length);
  		if (!ptr->kernel_data)
  			return -ENOMEM;
  		ptr->buffer_length = ptr->length;
  	}
  	if (ptr->flags & FD_RAW_WRITE) {
  		ret = fd_copyin(ptr->data, ptr->kernel_data, ptr->length);
  		if (ret)
  			return ret;
  	}

  	if (ptr->flags & FD_RAW_MORE) {

  		rcmd = &(ptr->next);

  		ptr->rate &= 0x43;

  		goto loop;

  	}

  
  	return 0;

  }
  
  static int raw_cmd_ioctl(int cmd, void __user *param)
  {

  	struct floppy_raw_cmd *my_raw_cmd;

  	int drive;
  	int ret2;
  	int ret;

  
  	if (FDCS->rawcmd <= 1)
  		FDCS->rawcmd = 1;
  	for (drive = 0; drive < N_DRIVE; drive++) {
  		if (FDC(drive) != fdc)
  			continue;
  		if (drive == current_drive) {
  			if (UDRS->fd_ref > 1) {
  				FDCS->rawcmd = 2;
  				break;
  			}
  		} else if (UDRS->fd_ref) {
  			FDCS->rawcmd = 2;
  			break;
  		}
  	}
  
  	if (FDCS->reset)
  		return -EIO;
  
  	ret = raw_cmd_copyin(cmd, param, &my_raw_cmd);
  	if (ret) {
  		raw_cmd_free(&my_raw_cmd);
  		return ret;
  	}
  
  	raw_cmd = my_raw_cmd;
  	cont = &raw_cmd_cont;

  	ret = wait_til_done(floppy_start, true);

  	debug_dcl(DP->flags, "calling disk change from raw_cmd ioctl
  ");

  
  	if (ret != -EINTR && FDCS->reset)
  		ret = -EIO;
  
  	DRS->track = NO_TRACK;
  
  	ret2 = raw_cmd_copyout(cmd, param, my_raw_cmd);
  	if (!ret)
  		ret = ret2;
  	raw_cmd_free(&my_raw_cmd);
  	return ret;
  }
  
  static int invalidate_drive(struct block_device *bdev)
  {
  	/* invalidate the buffer track to force a reread */
  	set_bit((long)bdev->bd_disk->private_data, &fake_change);
  	process_fd_request();
  	check_disk_change(bdev);
  	return 0;
  }

  static int set_geometry(unsigned int cmd, struct floppy_struct *g,

  			       int drive, int type, struct block_device *bdev)
  {
  	int cnt;
  
  	/* sanity checking for parameters. */
  	if (g->sect <= 0 ||
  	    g->head <= 0 ||
  	    g->track <= 0 || g->track > UDP->tracks >> STRETCH(g) ||
  	    /* check if reserved bits are set */