floppy: do put_disk on current dr if blk_init_queue fails
[opensuse:kernel.git] / drivers / block / floppy.c
1 /*
2  *  linux/drivers/block/floppy.c
3  *
4  *  Copyright (C) 1991, 1992  Linus Torvalds
5  *  Copyright (C) 1993, 1994  Alain Knaff
6  *  Copyright (C) 1998 Alan Cox
7  */
8
9 /*
10  * 02.12.91 - Changed to static variables to indicate need for reset
11  * and recalibrate. This makes some things easier (output_byte reset
12  * checking etc), and means less interrupt jumping in case of errors,
13  * so the code is hopefully easier to understand.
14  */
15
16 /*
17  * This file is certainly a mess. I've tried my best to get it working,
18  * but I don't like programming floppies, and I have only one anyway.
19  * Urgel. I should check for more errors, and do more graceful error
20  * recovery. Seems there are problems with several drives. I've tried to
21  * correct them. No promises.
22  */
23
24 /*
25  * As with hd.c, all routines within this file can (and will) be called
26  * by interrupts, so extreme caution is needed. A hardware interrupt
27  * handler may not sleep, or a kernel panic will happen. Thus I cannot
28  * call "floppy-on" directly, but have to set a special timer interrupt
29  * etc.
30  */
31
32 /*
33  * 28.02.92 - made track-buffering routines, based on the routines written
34  * by entropy@wintermute.wpi.edu (Lawrence Foard). Linus.
35  */
36
37 /*
38  * Automatic floppy-detection and formatting written by Werner Almesberger
39  * (almesber@nessie.cs.id.ethz.ch), who also corrected some problems with
40  * the floppy-change signal detection.
41  */
42
43 /*
44  * 1992/7/22 -- Hennus Bergman: Added better error reporting, fixed
45  * FDC data overrun bug, added some preliminary stuff for vertical
46  * recording support.
47  *
48  * 1992/9/17: Added DMA allocation & DMA functions. -- hhb.
49  *
50  * TODO: Errors are still not counted properly.
51  */
52
53 /* 1992/9/20
54  * Modifications for ``Sector Shifting'' by Rob Hooft (hooft@chem.ruu.nl)
55  * modeled after the freeware MS-DOS program fdformat/88 V1.8 by
56  * Christoph H. Hochst\"atter.
57  * I have fixed the shift values to the ones I always use. Maybe a new
58  * ioctl() should be created to be able to modify them.
59  * There is a bug in the driver that makes it impossible to format a
60  * floppy as the first thing after bootup.
61  */
62
63 /*
64  * 1993/4/29 -- Linus -- cleaned up the timer handling in the kernel, and
65  * this helped the floppy driver as well. Much cleaner, and still seems to
66  * work.
67  */
68
69 /* 1994/6/24 --bbroad-- added the floppy table entries and made
70  * minor modifications to allow 2.88 floppies to be run.
71  */
72
73 /* 1994/7/13 -- Paul Vojta -- modified the probing code to allow three or more
74  * disk types.
75  */
76
77 /*
78  * 1994/8/8 -- Alain Knaff -- Switched to fdpatch driver: Support for bigger
79  * format bug fixes, but unfortunately some new bugs too...
80  */
81
82 /* 1994/9/17 -- Koen Holtman -- added logging of physical floppy write
83  * errors to allow safe writing by specialized programs.
84  */
85
86 /* 1995/4/24 -- Dan Fandrich -- added support for Commodore 1581 3.5" disks
87  * by defining bit 1 of the "stretch" parameter to mean put sectors on the
88  * opposite side of the disk, leaving the sector IDs alone (i.e. Commodore's
89  * drives are "upside-down").
90  */
91
92 /*
93  * 1995/8/26 -- Andreas Busse -- added Mips support.
94  */
95
96 /*
97  * 1995/10/18 -- Ralf Baechle -- Portability cleanup; move machine dependent
98  * features to asm/floppy.h.
99  */
100
101 /*
102  * 1998/1/21 -- Richard Gooch <rgooch@atnf.csiro.au> -- devfs support
103  */
104
105 /*
106  * 1998/05/07 -- Russell King -- More portability cleanups; moved definition of
107  * interrupt and dma channel to asm/floppy.h. Cleaned up some formatting &
108  * use of '0' for NULL.
109  */
110
111 /*
112  * 1998/06/07 -- Alan Cox -- Merged the 2.0.34 fixes for resource allocation
113  * failures.
114  */
115
116 /*
117  * 1998/09/20 -- David Weinehall -- Added slow-down code for buggy PS/2-drives.
118  */
119
120 /*
121  * 1999/08/13 -- Paul Slootman -- floppy stopped working on Alpha after 24
122  * days, 6 hours, 32 minutes and 32 seconds (i.e. MAXINT jiffies; ints were
123  * being used to store jiffies, which are unsigned longs).
124  */
125
126 /*
127  * 2000/08/28 -- Arnaldo Carvalho de Melo <acme@conectiva.com.br>
128  * - get rid of check_region
129  * - s/suser/capable/
130  */
131
132 /*
133  * 2001/08/26 -- Paul Gortmaker - fix insmod oops on machines with no
134  * floppy controller (lingering task on list after module is gone... boom.)
135  */
136
137 /*
138  * 2002/02/07 -- Anton Altaparmakov - Fix io ports reservation to correct range
139  * (0x3f2-0x3f5, 0x3f7). This fix is a bit of a hack but the proper fix
140  * requires many non-obvious changes in arch dependent code.
141  */
142
143 /* 2003/07/28 -- Daniele Bellucci <bellucda@tiscali.it>.
144  * Better audit of register_blkdev.
145  */
146
147 #undef  FLOPPY_SILENT_DCL_CLEAR
148
149 #define REALLY_SLOW_IO
150
151 #define DEBUGT 2
152
153 #define DPRINT(format, args...) \
154         pr_info("floppy%d: " format, current_drive, ##args)
155
156 #define DCL_DEBUG               /* debug disk change line */
157 #ifdef DCL_DEBUG
158 #define debug_dcl(test, fmt, args...) \
159         do { if ((test) & FD_DEBUG) DPRINT(fmt, ##args); } while (0)
160 #else
161 #define debug_dcl(test, fmt, args...) \
162         do { if (0) DPRINT(fmt, ##args); } while (0)
163 #endif
164
165 /* do print messages for unexpected interrupts */
166 static int print_unex = 1;
167 #include <linux/module.h>
168 #include <linux/sched.h>
169 #include <linux/fs.h>
170 #include <linux/kernel.h>
171 #include <linux/timer.h>
172 #include <linux/workqueue.h>
173 #define FDPATCHES
174 #include <linux/fdreg.h>
175 #include <linux/fd.h>
176 #include <linux/hdreg.h>
177 #include <linux/errno.h>
178 #include <linux/slab.h>
179 #include <linux/mm.h>
180 #include <linux/bio.h>
181 #include <linux/string.h>
182 #include <linux/jiffies.h>
183 #include <linux/fcntl.h>
184 #include <linux/delay.h>
185 #include <linux/mc146818rtc.h>  /* CMOS defines */
186 #include <linux/ioport.h>
187 #include <linux/interrupt.h>
188 #include <linux/init.h>
189 #include <linux/platform_device.h>
190 #include <linux/mod_devicetable.h>
191 #include <linux/mutex.h>
192 #include <linux/io.h>
193 #include <linux/uaccess.h>
194 #include <linux/async.h>
195
196 /*
197  * PS/2 floppies have much slower step rates than regular floppies.
198  * It's been recommended that take about 1/4 of the default speed
199  * in some more extreme cases.
200  */
201 static DEFINE_MUTEX(floppy_mutex);
202 static int slow_floppy;
203
204 #include <asm/dma.h>
205 #include <asm/irq.h>
206
207 static int FLOPPY_IRQ = 6;
208 static int FLOPPY_DMA = 2;
209 static int can_use_virtual_dma = 2;
210 /* =======
211  * can use virtual DMA:
212  * 0 = use of virtual DMA disallowed by config
213  * 1 = use of virtual DMA prescribed by config
214  * 2 = no virtual DMA preference configured.  By default try hard DMA,
215  * but fall back on virtual DMA when not enough memory available
216  */
217
218 static int use_virtual_dma;
219 /* =======
220  * use virtual DMA
221  * 0 using hard DMA
222  * 1 using virtual DMA
223  * This variable is set to virtual when a DMA mem problem arises, and
224  * reset back in floppy_grab_irq_and_dma.
225  * It is not safe to reset it in other circumstances, because the floppy
226  * driver may have several buffers in use at once, and we do currently not
227  * record each buffers capabilities
228  */
229
230 static DEFINE_SPINLOCK(floppy_lock);
231
232 static unsigned short virtual_dma_port = 0x3f0;
233 irqreturn_t floppy_interrupt(int irq, void *dev_id);
234 static int set_dor(int fdc, char mask, char data);
235
236 #define K_64    0x10000         /* 64KB */
237
238 /* the following is the mask of allowed drives. By default units 2 and
239  * 3 of both floppy controllers are disabled, because switching on the
240  * motor of these drives causes system hangs on some PCI computers. drive
241  * 0 is the low bit (0x1), and drive 7 is the high bit (0x80). Bits are on if
242  * a drive is allowed.
243  *
244  * NOTE: This must come before we include the arch floppy header because
245  *       some ports reference this variable from there. -DaveM
246  */
247
248 static int allowed_drive_mask = 0x33;
249
250 #include <asm/floppy.h>
251
252 static int irqdma_allocated;
253
254 #include <linux/blkdev.h>
255 #include <linux/blkpg.h>
256 #include <linux/cdrom.h>        /* for the compatibility eject ioctl */
257 #include <linux/completion.h>
258
259 static struct request *current_req;
260 static void do_fd_request(struct request_queue *q);
261 static int set_next_request(void);
262
263 #ifndef fd_get_dma_residue
264 #define fd_get_dma_residue() get_dma_residue(FLOPPY_DMA)
265 #endif
266
267 /* Dma Memory related stuff */
268
269 #ifndef fd_dma_mem_free
270 #define fd_dma_mem_free(addr, size) free_pages(addr, get_order(size))
271 #endif
272
273 #ifndef fd_dma_mem_alloc
274 #define fd_dma_mem_alloc(size) __get_dma_pages(GFP_KERNEL, get_order(size))
275 #endif
276
277 static inline void fallback_on_nodma_alloc(char **addr, size_t l)
278 {
279 #ifdef FLOPPY_CAN_FALLBACK_ON_NODMA
280         if (*addr)
281                 return;         /* we have the memory */
282         if (can_use_virtual_dma != 2)
283                 return;         /* no fallback allowed */
284         pr_info("DMA memory shortage. Temporarily falling back on virtual DMA\n");
285         *addr = (char *)nodma_mem_alloc(l);
286 #else
287         return;
288 #endif
289 }
290
291 /* End dma memory related stuff */
292
293 static unsigned long fake_change;
294 static bool initialized;
295
296 #define ITYPE(x)        (((x) >> 2) & 0x1f)
297 #define TOMINOR(x)      ((x & 3) | ((x & 4) << 5))
298 #define UNIT(x)         ((x) & 0x03)            /* drive on fdc */
299 #define FDC(x)          (((x) & 0x04) >> 2)     /* fdc of drive */
300         /* reverse mapping from unit and fdc to drive */
301 #define REVDRIVE(fdc, unit) ((unit) + ((fdc) << 2))
302
303 #define DP      (&drive_params[current_drive])
304 #define DRS     (&drive_state[current_drive])
305 #define DRWE    (&write_errors[current_drive])
306 #define FDCS    (&fdc_state[fdc])
307
308 #define UDP     (&drive_params[drive])
309 #define UDRS    (&drive_state[drive])
310 #define UDRWE   (&write_errors[drive])
311 #define UFDCS   (&fdc_state[FDC(drive)])
312
313 #define PH_HEAD(floppy, head) (((((floppy)->stretch & 2) >> 1) ^ head) << 2)
314 #define STRETCH(floppy) ((floppy)->stretch & FD_STRETCH)
315
316 /* read/write */
317 #define COMMAND         (raw_cmd->cmd[0])
318 #define DR_SELECT       (raw_cmd->cmd[1])
319 #define TRACK           (raw_cmd->cmd[2])
320 #define HEAD            (raw_cmd->cmd[3])
321 #define SECTOR          (raw_cmd->cmd[4])
322 #define SIZECODE        (raw_cmd->cmd[5])
323 #define SECT_PER_TRACK  (raw_cmd->cmd[6])
324 #define GAP             (raw_cmd->cmd[7])
325 #define SIZECODE2       (raw_cmd->cmd[8])
326 #define NR_RW 9
327
328 /* format */
329 #define F_SIZECODE      (raw_cmd->cmd[2])
330 #define F_SECT_PER_TRACK (raw_cmd->cmd[3])
331 #define F_GAP           (raw_cmd->cmd[4])
332 #define F_FILL          (raw_cmd->cmd[5])
333 #define NR_F 6
334
335 /*
336  * Maximum disk size (in kilobytes).
337  * This default is used whenever the current disk size is unknown.
338  * [Now it is rather a minimum]
339  */
340 #define MAX_DISK_SIZE 4         /* 3984 */
341
342 /*
343  * globals used by 'result()'
344  */
345 #define MAX_REPLIES 16
346 static unsigned char reply_buffer[MAX_REPLIES];
347 static int inr;         /* size of reply buffer, when called from interrupt */
348 #define ST0             (reply_buffer[0])
349 #define ST1             (reply_buffer[1])
350 #define ST2             (reply_buffer[2])
351 #define ST3             (reply_buffer[0])       /* result of GETSTATUS */
352 #define R_TRACK         (reply_buffer[3])
353 #define R_HEAD          (reply_buffer[4])
354 #define R_SECTOR        (reply_buffer[5])
355 #define R_SIZECODE      (reply_buffer[6])
356
357 #define SEL_DLY         (2 * HZ / 100)
358
359 /*
360  * this struct defines the different floppy drive types.
361  */
362 static struct {
363         struct floppy_drive_params params;
364         const char *name;       /* name printed while booting */
365 } default_drive_params[] = {
366 /* NOTE: the time values in jiffies should be in msec!
367  CMOS drive type
368   |     Maximum data rate supported by drive type
369   |     |   Head load time, msec
370   |     |   |   Head unload time, msec (not used)
371   |     |   |   |     Step rate interval, usec
372   |     |   |   |     |       Time needed for spinup time (jiffies)
373   |     |   |   |     |       |      Timeout for spinning down (jiffies)
374   |     |   |   |     |       |      |   Spindown offset (where disk stops)
375   |     |   |   |     |       |      |   |     Select delay
376   |     |   |   |     |       |      |   |     |     RPS
377   |     |   |   |     |       |      |   |     |     |    Max number of tracks
378   |     |   |   |     |       |      |   |     |     |    |     Interrupt timeout
379   |     |   |   |     |       |      |   |     |     |    |     |   Max nonintlv. sectors
380   |     |   |   |     |       |      |   |     |     |    |     |   | -Max Errors- flags */
381 {{0,  500, 16, 16, 8000,    1*HZ, 3*HZ,  0, SEL_DLY, 5,  80, 3*HZ, 20, {3,1,2,0,2}, 0,
382       0, { 7, 4, 8, 2, 1, 5, 3,10}, 3*HZ/2, 0 }, "unknown" },
383
384 {{1,  300, 16, 16, 8000,    1*HZ, 3*HZ,  0, SEL_DLY, 5,  40, 3*HZ, 17, {3,1,2,0,2}, 0,
385       0, { 1, 0, 0, 0, 0, 0, 0, 0}, 3*HZ/2, 1 }, "360K PC" }, /*5 1/4 360 KB PC*/
386
387 {{2,  500, 16, 16, 6000, 4*HZ/10, 3*HZ, 14, SEL_DLY, 6,  83, 3*HZ, 17, {3,1,2,0,2}, 0,
388       0, { 2, 5, 6,23,10,20,12, 0}, 3*HZ/2, 2 }, "1.2M" }, /*5 1/4 HD AT*/
389
390 {{3,  250, 16, 16, 3000,    1*HZ, 3*HZ,  0, SEL_DLY, 5,  83, 3*HZ, 20, {3,1,2,0,2}, 0,
391       0, { 4,22,21,30, 3, 0, 0, 0}, 3*HZ/2, 4 }, "720k" }, /*3 1/2 DD*/
392
393 {{4,  500, 16, 16, 4000, 4*HZ/10, 3*HZ, 10, SEL_DLY, 5,  83, 3*HZ, 20, {3,1,2,0,2}, 0,
394       0, { 7, 4,25,22,31,21,29,11}, 3*HZ/2, 7 }, "1.44M" }, /*3 1/2 HD*/
395
396 {{5, 1000, 15,  8, 3000, 4*HZ/10, 3*HZ, 10, SEL_DLY, 5,  83, 3*HZ, 40, {3,1,2,0,2}, 0,
397       0, { 7, 8, 4,25,28,22,31,21}, 3*HZ/2, 8 }, "2.88M AMI BIOS" }, /*3 1/2 ED*/
398
399 {{6, 1000, 15,  8, 3000, 4*HZ/10, 3*HZ, 10, SEL_DLY, 5,  83, 3*HZ, 40, {3,1,2,0,2}, 0,
400       0, { 7, 8, 4,25,28,22,31,21}, 3*HZ/2, 8 }, "2.88M" } /*3 1/2 ED*/
401 /*    |  --autodetected formats---    |      |      |
402  *    read_track                      |      |    Name printed when booting
403  *                                    |     Native format
404  *                  Frequency of disk change checks */
405 };
406
407 static struct floppy_drive_params drive_params[N_DRIVE];
408 static struct floppy_drive_struct drive_state[N_DRIVE];
409 static struct floppy_write_errors write_errors[N_DRIVE];
410 static struct timer_list motor_off_timer[N_DRIVE];
411 static struct gendisk *disks[N_DRIVE];
412 static struct block_device *opened_bdev[N_DRIVE];
413 static DEFINE_MUTEX(open_lock);
414 static struct floppy_raw_cmd *raw_cmd, default_raw_cmd;
415 static int fdc_queue;
416
417 /*
418  * This struct defines the different floppy types.
419  *
420  * Bit 0 of 'stretch' tells if the tracks need to be doubled for some
421  * types (e.g. 360kB diskette in 1.2MB drive, etc.).  Bit 1 of 'stretch'
422  * tells if the disk is in Commodore 1581 format, which means side 0 sectors
423  * are located on side 1 of the disk but with a side 0 ID, and vice-versa.
424  * This is the same as the Sharp MZ-80 5.25" CP/M disk format, except that the
425  * 1581's logical side 0 is on physical side 1, whereas the Sharp's logical
426  * side 0 is on physical side 0 (but with the misnamed sector IDs).
427  * 'stretch' should probably be renamed to something more general, like
428  * 'options'.
429  *
430  * Bits 2 through 9 of 'stretch' tell the number of the first sector.
431  * The LSB (bit 2) is flipped. For most disks, the first sector
432  * is 1 (represented by 0x00<<2).  For some CP/M and music sampler
433  * disks (such as Ensoniq EPS 16plus) it is 0 (represented as 0x01<<2).
434  * For Amstrad CPC disks it is 0xC1 (represented as 0xC0<<2).
435  *
436  * Other parameters should be self-explanatory (see also setfdprm(8)).
437  */
438 /*
439             Size
440              |  Sectors per track
441              |  | Head
442              |  | |  Tracks
443              |  | |  | Stretch
444              |  | |  | |  Gap 1 size
445              |  | |  | |    |  Data rate, | 0x40 for perp
446              |  | |  | |    |    |  Spec1 (stepping rate, head unload
447              |  | |  | |    |    |    |    /fmt gap (gap2) */
448 static struct floppy_struct floppy_type[32] = {
449         {    0, 0,0, 0,0,0x00,0x00,0x00,0x00,NULL    }, /*  0 no testing    */
450         {  720, 9,2,40,0,0x2A,0x02,0xDF,0x50,"d360"  }, /*  1 360KB PC      */
451         { 2400,15,2,80,0,0x1B,0x00,0xDF,0x54,"h1200" }, /*  2 1.2MB AT      */
452         {  720, 9,1,80,0,0x2A,0x02,0xDF,0x50,"D360"  }, /*  3 360KB SS 3.5" */
453         { 1440, 9,2,80,0,0x2A,0x02,0xDF,0x50,"D720"  }, /*  4 720KB 3.5"    */
454         {  720, 9,2,40,1,0x23,0x01,0xDF,0x50,"h360"  }, /*  5 360KB AT      */
455         { 1440, 9,2,80,0,0x23,0x01,0xDF,0x50,"h720"  }, /*  6 720KB AT      */
456         { 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,"H1440" }, /*  7 1.44MB 3.5"   */
457         { 5760,36,2,80,0,0x1B,0x43,0xAF,0x54,"E2880" }, /*  8 2.88MB 3.5"   */
458         { 6240,39,2,80,0,0x1B,0x43,0xAF,0x28,"E3120" }, /*  9 3.12MB 3.5"   */
459
460         { 2880,18,2,80,0,0x25,0x00,0xDF,0x02,"h1440" }, /* 10 1.44MB 5.25"  */
461         { 3360,21,2,80,0,0x1C,0x00,0xCF,0x0C,"H1680" }, /* 11 1.68MB 3.5"   */
462         {  820,10,2,41,1,0x25,0x01,0xDF,0x2E,"h410"  }, /* 12 410KB 5.25"   */
463         { 1640,10,2,82,0,0x25,0x02,0xDF,0x2E,"H820"  }, /* 13 820KB 3.5"    */
464         { 2952,18,2,82,0,0x25,0x00,0xDF,0x02,"h1476" }, /* 14 1.48MB 5.25"  */
465         { 3444,21,2,82,0,0x25,0x00,0xDF,0x0C,"H1722" }, /* 15 1.72MB 3.5"   */
466         {  840,10,2,42,1,0x25,0x01,0xDF,0x2E,"h420"  }, /* 16 420KB 5.25"   */
467         { 1660,10,2,83,0,0x25,0x02,0xDF,0x2E,"H830"  }, /* 17 830KB 3.5"    */
468         { 2988,18,2,83,0,0x25,0x00,0xDF,0x02,"h1494" }, /* 18 1.49MB 5.25"  */
469         { 3486,21,2,83,0,0x25,0x00,0xDF,0x0C,"H1743" }, /* 19 1.74 MB 3.5"  */
470
471         { 1760,11,2,80,0,0x1C,0x09,0xCF,0x00,"h880"  }, /* 20 880KB 5.25"   */
472         { 2080,13,2,80,0,0x1C,0x01,0xCF,0x00,"D1040" }, /* 21 1.04MB 3.5"   */
473         { 2240,14,2,80,0,0x1C,0x19,0xCF,0x00,"D1120" }, /* 22 1.12MB 3.5"   */
474         { 3200,20,2,80,0,0x1C,0x20,0xCF,0x2C,"h1600" }, /* 23 1.6MB 5.25"   */
475         { 3520,22,2,80,0,0x1C,0x08,0xCF,0x2e,"H1760" }, /* 24 1.76MB 3.5"   */
476         { 3840,24,2,80,0,0x1C,0x20,0xCF,0x00,"H1920" }, /* 25 1.92MB 3.5"   */
477         { 6400,40,2,80,0,0x25,0x5B,0xCF,0x00,"E3200" }, /* 26 3.20MB 3.5"   */
478         { 7040,44,2,80,0,0x25,0x5B,0xCF,0x00,"E3520" }, /* 27 3.52MB 3.5"   */
479         { 7680,48,2,80,0,0x25,0x63,0xCF,0x00,"E3840" }, /* 28 3.84MB 3.5"   */
480         { 3680,23,2,80,0,0x1C,0x10,0xCF,0x00,"H1840" }, /* 29 1.84MB 3.5"   */
481
482         { 1600,10,2,80,0,0x25,0x02,0xDF,0x2E,"D800"  }, /* 30 800KB 3.5"    */
483         { 3200,20,2,80,0,0x1C,0x00,0xCF,0x2C,"H1600" }, /* 31 1.6MB 3.5"    */
484 };
485
486 #define SECTSIZE (_FD_SECTSIZE(*floppy))
487
488 /* Auto-detection: Disk type used until the next media change occurs. */
489 static struct floppy_struct *current_type[N_DRIVE];
490
491 /*
492  * User-provided type information. current_type points to
493  * the respective entry of this array.
494  */
495 static struct floppy_struct user_params[N_DRIVE];
496
497 static sector_t floppy_sizes[256];
498
499 static char floppy_device_name[] = "floppy";
500
501 /*
502  * The driver is trying to determine the correct media format
503  * while probing is set. rw_interrupt() clears it after a
504  * successful access.
505  */
506 static int probing;
507
508 /* Synchronization of FDC access. */
509 #define FD_COMMAND_NONE         -1
510 #define FD_COMMAND_ERROR        2
511 #define FD_COMMAND_OKAY         3
512
513 static volatile int command_status = FD_COMMAND_NONE;
514 static unsigned long fdc_busy;
515 static DECLARE_WAIT_QUEUE_HEAD(fdc_wait);
516 static DECLARE_WAIT_QUEUE_HEAD(command_done);
517
518 /* Errors during formatting are counted here. */
519 static int format_errors;
520
521 /* Format request descriptor. */
522 static struct format_descr format_req;
523
524 /*
525  * Rate is 0 for 500kb/s, 1 for 300kbps, 2 for 250kbps
526  * Spec1 is 0xSH, where S is stepping rate (F=1ms, E=2ms, D=3ms etc),
527  * H is head unload time (1=16ms, 2=32ms, etc)
528  */
529
530 /*
531  * Track buffer
532  * Because these are written to by the DMA controller, they must
533  * not contain a 64k byte boundary crossing, or data will be
534  * corrupted/lost.
535  */
536 static char *floppy_track_buffer;
537 static int max_buffer_sectors;
538
539 static int *errors;
540 typedef void (*done_f)(int);
541 static const struct cont_t {
542         void (*interrupt)(void);
543                                 /* this is called after the interrupt of the
544                                  * main command */
545         void (*redo)(void);     /* this is called to retry the operation */
546         void (*error)(void);    /* this is called to tally an error */
547         done_f done;            /* this is called to say if the operation has
548                                  * succeeded/failed */
549 } *cont;
550
551 static void floppy_ready(void);
552 static void floppy_start(void);
553 static void process_fd_request(void);
554 static void recalibrate_floppy(void);
555 static void floppy_shutdown(struct work_struct *);
556
557 static int floppy_request_regions(int);
558 static void floppy_release_regions(int);
559 static int floppy_grab_irq_and_dma(void);
560 static void floppy_release_irq_and_dma(void);
561
562 /*
563  * The "reset" variable should be tested whenever an interrupt is scheduled,
564  * after the commands have been sent. This is to ensure that the driver doesn't
565  * get wedged when the interrupt doesn't come because of a failed command.
566  * reset doesn't need to be tested before sending commands, because
567  * output_byte is automatically disabled when reset is set.
568  */
569 static void reset_fdc(void);
570
571 /*
572  * These are global variables, as that's the easiest way to give
573  * information to interrupts. They are the data used for the current
574  * request.
575  */
576 #define NO_TRACK        -1
577 #define NEED_1_RECAL    -2
578 #define NEED_2_RECAL    -3
579
580 static atomic_t usage_count = ATOMIC_INIT(0);
581
582 /* buffer related variables */
583 static int buffer_track = -1;
584 static int buffer_drive = -1;
585 static int buffer_min = -1;
586 static int buffer_max = -1;
587
588 /* fdc related variables, should end up in a struct */
589 static struct floppy_fdc_state fdc_state[N_FDC];
590 static int fdc;                 /* current fdc */
591
592 static struct workqueue_struct *floppy_wq;
593
594 static struct floppy_struct *_floppy = floppy_type;
595 static unsigned char current_drive;
596 static long current_count_sectors;
597 static unsigned char fsector_t; /* sector in track */
598 static unsigned char in_sector_offset;  /* offset within physical sector,
599                                          * expressed in units of 512 bytes */
600
601 static inline bool drive_no_geom(int drive)
602 {
603         return !current_type[drive] && !ITYPE(UDRS->fd_device);
604 }
605
606 #ifndef fd_eject
607 static inline int fd_eject(int drive)
608 {
609         return -EINVAL;
610 }
611 #endif
612
613 /*
614  * Debugging
615  * =========
616  */
617 #ifdef DEBUGT
618 static long unsigned debugtimer;
619
620 static inline void set_debugt(void)
621 {
622         debugtimer = jiffies;
623 }
624
625 static inline void debugt(const char *func, const char *msg)
626 {
627         if (DP->flags & DEBUGT)
628                 pr_info("%s:%s dtime=%lu\n", func, msg, jiffies - debugtimer);
629 }
630 #else
631 static inline void set_debugt(void) { }
632 static inline void debugt(const char *func, const char *msg) { }
633 #endif /* DEBUGT */
634
635
636 static DECLARE_DELAYED_WORK(fd_timeout, floppy_shutdown);
637 static const char *timeout_message;
638
639 static void is_alive(const char *func, const char *message)
640 {
641         /* this routine checks whether the floppy driver is "alive" */
642         if (test_bit(0, &fdc_busy) && command_status < 2 &&
643             !delayed_work_pending(&fd_timeout)) {
644                 DPRINT("%s: timeout handler died.  %s\n", func, message);
645         }
646 }
647
648 static void (*do_floppy)(void) = NULL;
649
650 #define OLOGSIZE 20
651
652 static void (*lasthandler)(void);
653 static unsigned long interruptjiffies;
654 static unsigned long resultjiffies;
655 static int resultsize;
656 static unsigned long lastredo;
657
658 static struct output_log {
659         unsigned char data;
660         unsigned char status;
661         unsigned long jiffies;
662 } output_log[OLOGSIZE];
663
664 static int output_log_pos;
665
666 #define current_reqD -1
667 #define MAXTIMEOUT -2
668
669 static void __reschedule_timeout(int drive, const char *message)
670 {
671         unsigned long delay;
672
673         if (drive == current_reqD)
674                 drive = current_drive;
675         __cancel_delayed_work(&fd_timeout);
676
677         if (drive < 0 || drive >= N_DRIVE) {
678                 delay = 20UL * HZ;
679                 drive = 0;
680         } else
681                 delay = UDP->timeout;
682
683         queue_delayed_work(floppy_wq, &fd_timeout, delay);
684         if (UDP->flags & FD_DEBUG)
685                 DPRINT("reschedule timeout %s\n", message);
686         timeout_message = message;
687 }
688
689 static void reschedule_timeout(int drive, const char *message)
690 {
691         unsigned long flags;
692
693         spin_lock_irqsave(&floppy_lock, flags);
694         __reschedule_timeout(drive, message);
695         spin_unlock_irqrestore(&floppy_lock, flags);
696 }
697
698 #define INFBOUND(a, b) (a) = max_t(int, a, b)
699 #define SUPBOUND(a, b) (a) = min_t(int, a, b)
700
701 /*
702  * Bottom half floppy driver.
703  * ==========================
704  *
705  * This part of the file contains the code talking directly to the hardware,
706  * and also the main service loop (seek-configure-spinup-command)
707  */
708
709 /*
710  * disk change.
711  * This routine is responsible for maintaining the FD_DISK_CHANGE flag,
712  * and the last_checked date.
713  *
714  * last_checked is the date of the last check which showed 'no disk change'
715  * FD_DISK_CHANGE is set under two conditions:
716  * 1. The floppy has been changed after some i/o to that floppy already
717  *    took place.
718  * 2. No floppy disk is in the drive. This is done in order to ensure that
719  *    requests are quickly flushed in case there is no disk in the drive. It
720  *    follows that FD_DISK_CHANGE can only be cleared if there is a disk in
721  *    the drive.
722  *
723  * For 1., maxblock is observed. Maxblock is 0 if no i/o has taken place yet.
724  * For 2., FD_DISK_NEWCHANGE is watched. FD_DISK_NEWCHANGE is cleared on
725  *  each seek. If a disk is present, the disk change line should also be
726  *  cleared on each seek. Thus, if FD_DISK_NEWCHANGE is clear, but the disk
727  *  change line is set, this means either that no disk is in the drive, or
728  *  that it has been removed since the last seek.
729  *
730  * This means that we really have a third possibility too:
731  *  The floppy has been changed after the last seek.
732  */
733
734 static int disk_change(int drive)
735 {
736         int fdc = FDC(drive);
737
738         if (time_before(jiffies, UDRS->select_date + UDP->select_delay))
739                 DPRINT("WARNING disk change called early\n");
740         if (!(FDCS->dor & (0x10 << UNIT(drive))) ||
741             (FDCS->dor & 3) != UNIT(drive) || fdc != FDC(drive)) {
742                 DPRINT("probing disk change on unselected drive\n");
743                 DPRINT("drive=%d fdc=%d dor=%x\n", drive, FDC(drive),
744                        (unsigned int)FDCS->dor);
745         }
746
747         debug_dcl(UDP->flags,
748                   "checking disk change line for drive %d\n", drive);
749         debug_dcl(UDP->flags, "jiffies=%lu\n", jiffies);
750         debug_dcl(UDP->flags, "disk change line=%x\n", fd_inb(FD_DIR) & 0x80);
751         debug_dcl(UDP->flags, "flags=%lx\n", UDRS->flags);
752
753         if (UDP->flags & FD_BROKEN_DCL)
754                 return test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags);
755         if ((fd_inb(FD_DIR) ^ UDP->flags) & 0x80) {
756                 set_bit(FD_VERIFY_BIT, &UDRS->flags);
757                                         /* verify write protection */
758
759                 if (UDRS->maxblock)     /* mark it changed */
760                         set_bit(FD_DISK_CHANGED_BIT, &UDRS->flags);
761
762                 /* invalidate its geometry */
763                 if (UDRS->keep_data >= 0) {
764                         if ((UDP->flags & FTD_MSG) &&
765                             current_type[drive] != NULL)
766                                 DPRINT("Disk type is undefined after disk change\n");
767                         current_type[drive] = NULL;
768                         floppy_sizes[TOMINOR(drive)] = MAX_DISK_SIZE << 1;
769                 }
770
771                 return 1;
772         } else {
773                 UDRS->last_checked = jiffies;
774                 clear_bit(FD_DISK_NEWCHANGE_BIT, &UDRS->flags);
775         }
776         return 0;
777 }
778
779 static inline int is_selected(int dor, int unit)
780 {
781         return ((dor & (0x10 << unit)) && (dor & 3) == unit);
782 }
783
784 static bool is_ready_state(int status)
785 {
786         int state = status & (STATUS_READY | STATUS_DIR | STATUS_DMA);
787         return state == STATUS_READY;
788 }
789
790 static int set_dor(int fdc, char mask, char data)
791 {
792         unsigned char unit;
793         unsigned char drive;
794         unsigned char newdor;
795         unsigned char olddor;
796
797         if (FDCS->address == -1)
798                 return -1;
799
800         olddor = FDCS->dor;
801         newdor = (olddor & mask) | data;
802         if (newdor != olddor) {
803                 unit = olddor & 0x3;
804                 if (is_selected(olddor, unit) && !is_selected(newdor, unit)) {
805                         drive = REVDRIVE(fdc, unit);
806                         debug_dcl(UDP->flags,
807                                   "calling disk change from set_dor\n");
808                         disk_change(drive);
809                 }
810                 FDCS->dor = newdor;
811                 fd_outb(newdor, FD_DOR);
812
813                 unit = newdor & 0x3;
814                 if (!is_selected(olddor, unit) && is_selected(newdor, unit)) {
815                         drive = REVDRIVE(fdc, unit);
816                         UDRS->select_date = jiffies;
817                 }
818         }
819         return olddor;
820 }
821
822 static void twaddle(void)
823 {
824         if (DP->select_delay)
825                 return;
826         fd_outb(FDCS->dor & ~(0x10 << UNIT(current_drive)), FD_DOR);
827         fd_outb(FDCS->dor, FD_DOR);
828         DRS->select_date = jiffies;
829 }
830
831 /*
832  * Reset all driver information about the current fdc.
833  * This is needed after a reset, and after a raw command.
834  */
835 static void reset_fdc_info(int mode)
836 {
837         int drive;
838
839         FDCS->spec1 = FDCS->spec2 = -1;
840         FDCS->need_configure = 1;
841         FDCS->perp_mode = 1;
842         FDCS->rawcmd = 0;
843         for (drive = 0; drive < N_DRIVE; drive++)
844                 if (FDC(drive) == fdc && (mode || UDRS->track != NEED_1_RECAL))
845                         UDRS->track = NEED_2_RECAL;
846 }
847
848 /* selects the fdc and drive, and enables the fdc's input/dma. */
849 static void set_fdc(int drive)
850 {
851         if (drive >= 0 && drive < N_DRIVE) {
852                 fdc = FDC(drive);
853                 current_drive = drive;
854         }
855         if (fdc != 1 && fdc != 0) {
856                 pr_info("bad fdc value\n");
857                 return;
858         }
859         set_dor(fdc, ~0, 8);
860 #if N_FDC > 1
861         set_dor(1 - fdc, ~8, 0);
862 #endif
863         if (FDCS->rawcmd == 2)
864                 reset_fdc_info(1);
865         if (fd_inb(FD_STATUS) != STATUS_READY)
866                 FDCS->reset = 1;
867 }
868
869 /* locks the driver */
870 static int lock_fdc(int drive, bool interruptible)
871 {
872         if (WARN(atomic_read(&usage_count) == 0,
873                  "Trying to lock fdc while usage count=0\n"))
874                 return -1;
875
876         if (wait_event_interruptible(fdc_wait, !test_and_set_bit(0, &fdc_busy)))
877                 return -EINTR;
878
879         command_status = FD_COMMAND_NONE;
880
881         reschedule_timeout(drive, "lock fdc");
882         set_fdc(drive);
883         return 0;
884 }
885
886 /* unlocks the driver */
887 static void unlock_fdc(void)
888 {
889         if (!test_bit(0, &fdc_busy))
890                 DPRINT("FDC access conflict!\n");
891
892         raw_cmd = NULL;
893         command_status = FD_COMMAND_NONE;
894         __cancel_delayed_work(&fd_timeout);
895         do_floppy = NULL;
896         cont = NULL;
897         clear_bit(0, &fdc_busy);
898         wake_up(&fdc_wait);
899 }
900
901 /* switches the motor off after a given timeout */
902 static void motor_off_callback(unsigned long nr)
903 {
904         unsigned char mask = ~(0x10 << UNIT(nr));
905
906         set_dor(FDC(nr), mask, 0);
907 }
908
909 /* schedules motor off */
910 static void floppy_off(unsigned int drive)
911 {
912         unsigned long volatile delta;
913         int fdc = FDC(drive);
914
915         if (!(FDCS->dor & (0x10 << UNIT(drive))))
916                 return;
917
918         del_timer(motor_off_timer + drive);
919
920         /* make spindle stop in a position which minimizes spinup time
921          * next time */
922         if (UDP->rps) {
923                 delta = jiffies - UDRS->first_read_date + HZ -
924                     UDP->spindown_offset;
925                 delta = ((delta * UDP->rps) % HZ) / UDP->rps;
926                 motor_off_timer[drive].expires =
927                     jiffies + UDP->spindown - delta;
928         }
929         add_timer(motor_off_timer + drive);
930 }
931
932 /*
933  * cycle through all N_DRIVE floppy drives, for disk change testing.
934  * stopping at current drive. This is done before any long operation, to
935  * be sure to have up to date disk change information.
936  */
937 static void scandrives(void)
938 {
939         int i;
940         int drive;
941         int saved_drive;
942
943         if (DP->select_delay)
944                 return;
945
946         saved_drive = current_drive;
947         for (i = 0; i < N_DRIVE; i++) {
948                 drive = (saved_drive + i + 1) % N_DRIVE;
949                 if (UDRS->fd_ref == 0 || UDP->select_delay != 0)
950                         continue;       /* skip closed drives */
951                 set_fdc(drive);
952                 if (!(set_dor(fdc, ~3, UNIT(drive) | (0x10 << UNIT(drive))) &
953                       (0x10 << UNIT(drive))))
954                         /* switch the motor off again, if it was off to
955                          * begin with */
956                         set_dor(fdc, ~(0x10 << UNIT(drive)), 0);
957         }
958         set_fdc(saved_drive);
959 }
960
961 static void empty(void)
962 {
963 }
964
965 static DECLARE_WORK(floppy_work, NULL);
966
967 static void schedule_bh(void (*handler)(void))
968 {
969         WARN_ON(work_pending(&floppy_work));
970
971         PREPARE_WORK(&floppy_work, (work_func_t)handler);
972         queue_work(floppy_wq, &floppy_work);
973 }
974
975 static DECLARE_DELAYED_WORK(fd_timer, NULL);
976
977 static void cancel_activity(void)
978 {
979         do_floppy = NULL;
980         cancel_delayed_work_sync(&fd_timer);
981         cancel_work_sync(&floppy_work);
982 }
983
984 /* this function makes sure that the disk stays in the drive during the
985  * transfer */
986 static void fd_watchdog(struct work_struct *arg)
987 {
988         debug_dcl(DP->flags, "calling disk change from watchdog\n");
989
990         if (disk_change(current_drive)) {
991                 DPRINT("disk removed during i/o\n");
992                 cancel_activity();
993                 cont->done(0);
994                 reset_fdc();
995         } else {
996                 cancel_delayed_work(&fd_timer);
997                 PREPARE_DELAYED_WORK(&fd_timer, fd_watchdog);
998                 queue_delayed_work(floppy_wq, &fd_timer, HZ / 10);
999         }
1000 }
1001
1002 static void main_command_interrupt(void)
1003 {
1004         cancel_delayed_work(&fd_timer);
1005         cont->interrupt();
1006 }
1007
1008 /* waits for a delay (spinup or select) to pass */
1009 static int fd_wait_for_completion(unsigned long expires, work_func_t function)
1010 {
1011         if (FDCS->reset) {
1012                 reset_fdc();    /* do the reset during sleep to win time
1013                                  * if we don't need to sleep, it's a good
1014                                  * occasion anyways */
1015                 return 1;
1016         }
1017
1018         if (time_before(jiffies, expires)) {
1019                 cancel_delayed_work(&fd_timer);
1020                 PREPARE_DELAYED_WORK(&fd_timer, function);
1021                 queue_delayed_work(floppy_wq, &fd_timer, expires - jiffies);
1022                 return 1;
1023         }
1024         return 0;
1025 }
1026
1027 static void setup_DMA(void)
1028 {
1029         unsigned long f;
1030
1031         if (raw_cmd->length == 0) {
1032                 int i;
1033
1034                 pr_info("zero dma transfer size:");
1035                 for (i = 0; i < raw_cmd->cmd_count; i++)
1036                         pr_cont("%x,", raw_cmd->cmd[i]);
1037                 pr_cont("\n");
1038                 cont->done(0);
1039                 FDCS->reset = 1;
1040                 return;
1041         }
1042         if (((unsigned long)raw_cmd->kernel_data) % 512) {
1043                 pr_info("non aligned address: %p\n", raw_cmd->kernel_data);
1044                 cont->done(0);
1045                 FDCS->reset = 1;
1046                 return;
1047         }
1048         f = claim_dma_lock();
1049         fd_disable_dma();
1050 #ifdef fd_dma_setup
1051         if (fd_dma_setup(raw_cmd->kernel_data, raw_cmd->length,
1052                          (raw_cmd->flags & FD_RAW_READ) ?
1053                          DMA_MODE_READ : DMA_MODE_WRITE, FDCS->address) < 0) {
1054                 release_dma_lock(f);
1055                 cont->done(0);
1056                 FDCS->reset = 1;
1057                 return;
1058         }
1059         release_dma_lock(f);
1060 #else
1061         fd_clear_dma_ff();
1062         fd_cacheflush(raw_cmd->kernel_data, raw_cmd->length);
1063         fd_set_dma_mode((raw_cmd->flags & FD_RAW_READ) ?
1064                         DMA_MODE_READ : DMA_MODE_WRITE);
1065         fd_set_dma_addr(raw_cmd->kernel_data);
1066         fd_set_dma_count(raw_cmd->length);
1067         virtual_dma_port = FDCS->address;
1068         fd_enable_dma();
1069         release_dma_lock(f);
1070 #endif
1071 }
1072
1073 static void show_floppy(void);
1074
1075 /* waits until the fdc becomes ready */
1076 static int wait_til_ready(void)
1077 {
1078         int status;
1079         int counter;
1080
1081         if (FDCS->reset)
1082                 return -1;
1083         for (counter = 0; counter < 10000; counter++) {
1084                 status = fd_inb(FD_STATUS);
1085                 if (status & STATUS_READY)
1086                         return status;
1087         }
1088         if (initialized) {
1089                 DPRINT("Getstatus times out (%x) on fdc %d\n", status, fdc);
1090                 show_floppy();
1091         }
1092         FDCS->reset = 1;
1093         return -1;
1094 }
1095
1096 /* sends a command byte to the fdc */
1097 static int output_byte(char byte)
1098 {
1099         int status = wait_til_ready();
1100
1101         if (status < 0)
1102                 return -1;
1103
1104         if (is_ready_state(status)) {
1105                 fd_outb(byte, FD_DATA);
1106                 output_log[output_log_pos].data = byte;
1107                 output_log[output_log_pos].status = status;
1108                 output_log[output_log_pos].jiffies = jiffies;
1109                 output_log_pos = (output_log_pos + 1) % OLOGSIZE;
1110                 return 0;
1111         }
1112         FDCS->reset = 1;
1113         if (initialized) {
1114                 DPRINT("Unable to send byte %x to FDC. Fdc=%x Status=%x\n",
1115                        byte, fdc, status);
1116                 show_floppy();
1117         }
1118         return -1;
1119 }
1120
1121 /* gets the response from the fdc */
1122 static int result(void)
1123 {
1124         int i;
1125         int status = 0;
1126
1127         for (i = 0; i < MAX_REPLIES; i++) {
1128                 status = wait_til_ready();
1129                 if (status < 0)
1130                         break;
1131                 status &= STATUS_DIR | STATUS_READY | STATUS_BUSY | STATUS_DMA;
1132                 if ((status & ~STATUS_BUSY) == STATUS_READY) {
1133                         resultjiffies = jiffies;
1134                         resultsize = i;
1135                         return i;
1136                 }
1137                 if (status == (STATUS_DIR | STATUS_READY | STATUS_BUSY))
1138                         reply_buffer[i] = fd_inb(FD_DATA);
1139                 else
1140                         break;
1141         }
1142         if (initialized) {
1143                 DPRINT("get result error. Fdc=%d Last status=%x Read bytes=%d\n",
1144                        fdc, status, i);
1145                 show_floppy();
1146         }
1147         FDCS->reset = 1;
1148         return -1;
1149 }
1150
1151 #define MORE_OUTPUT -2
1152 /* does the fdc need more output? */
1153 static int need_more_output(void)
1154 {
1155         int status = wait_til_ready();
1156
1157         if (status < 0)
1158                 return -1;
1159
1160         if (is_ready_state(status))
1161                 return MORE_OUTPUT;
1162
1163         return result();
1164 }
1165
1166 /* Set perpendicular mode as required, based on data rate, if supported.
1167  * 82077 Now tested. 1Mbps data rate only possible with 82077-1.
1168  */
1169 static void perpendicular_mode(void)
1170 {
1171         unsigned char perp_mode;
1172
1173         if (raw_cmd->rate & 0x40) {
1174                 switch (raw_cmd->rate & 3) {
1175                 case 0:
1176                         perp_mode = 2;
1177                         break;
1178                 case 3:
1179                         perp_mode = 3;
1180                         break;
1181                 default:
1182                         DPRINT("Invalid data rate for perpendicular mode!\n");
1183                         cont->done(0);
1184                         FDCS->reset = 1;
1185                                         /*
1186                                          * convenient way to return to
1187                                          * redo without too much hassle
1188                                          * (deep stack et al.)
1189                                          */
1190                         return;
1191                 }
1192         } else
1193                 perp_mode = 0;
1194
1195         if (FDCS->perp_mode == perp_mode)
1196                 return;
1197         if (FDCS->version >= FDC_82077_ORIG) {
1198                 output_byte(FD_PERPENDICULAR);
1199                 output_byte(perp_mode);
1200                 FDCS->perp_mode = perp_mode;
1201         } else if (perp_mode) {
1202                 DPRINT("perpendicular mode not supported by this FDC.\n");
1203         }
1204 }                               /* perpendicular_mode */
1205
1206 static int fifo_depth = 0xa;
1207 static int no_fifo;
1208
1209 static int fdc_configure(void)
1210 {
1211         /* Turn on FIFO */
1212         output_byte(FD_CONFIGURE);
1213         if (need_more_output() != MORE_OUTPUT)
1214                 return 0;
1215         output_byte(0);
1216         output_byte(0x10 | (no_fifo & 0x20) | (fifo_depth & 0xf));
1217         output_byte(0);         /* pre-compensation from track
1218                                    0 upwards */
1219         return 1;
1220 }
1221
1222 #define NOMINAL_DTR 500
1223
1224 /* Issue a "SPECIFY" command to set the step rate time, head unload time,
1225  * head load time, and DMA disable flag to values needed by floppy.
1226  *
1227  * The value "dtr" is the data transfer rate in Kbps.  It is needed
1228  * to account for the data rate-based scaling done by the 82072 and 82077
1229  * FDC types.  This parameter is ignored for other types of FDCs (i.e.
1230  * 8272a).
1231  *
1232  * Note that changing the data transfer rate has a (probably deleterious)
1233  * effect on the parameters subject to scaling for 82072/82077 FDCs, so
1234  * fdc_specify is called again after each data transfer rate
1235  * change.
1236  *
1237  * srt: 1000 to 16000 in microseconds
1238  * hut: 16 to 240 milliseconds
1239  * hlt: 2 to 254 milliseconds
1240  *
1241  * These values are rounded up to the next highest available delay time.
1242  */
1243 static void fdc_specify(void)
1244 {
1245         unsigned char spec1;
1246         unsigned char spec2;
1247         unsigned long srt;
1248         unsigned long hlt;
1249         unsigned long hut;
1250         unsigned long dtr = NOMINAL_DTR;
1251         unsigned long scale_dtr = NOMINAL_DTR;
1252         int hlt_max_code = 0x7f;
1253         int hut_max_code = 0xf;
1254
1255         if (FDCS->need_configure && FDCS->version >= FDC_82072A) {
1256                 fdc_configure();
1257                 FDCS->need_configure = 0;
1258         }
1259
1260         switch (raw_cmd->rate & 0x03) {
1261         case 3:
1262                 dtr = 1000;
1263                 break;
1264         case 1:
1265                 dtr = 300;
1266                 if (FDCS->version >= FDC_82078) {
1267                         /* chose the default rate table, not the one
1268                          * where 1 = 2 Mbps */
1269                         output_byte(FD_DRIVESPEC);
1270                         if (need_more_output() == MORE_OUTPUT) {
1271                                 output_byte(UNIT(current_drive));
1272                                 output_byte(0xc0);
1273                         }
1274                 }
1275                 break;
1276         case 2:
1277                 dtr = 250;
1278                 break;
1279         }
1280
1281         if (FDCS->version >= FDC_82072) {
1282                 scale_dtr = dtr;
1283                 hlt_max_code = 0x00;    /* 0==256msec*dtr0/dtr (not linear!) */
1284                 hut_max_code = 0x0;     /* 0==256msec*dtr0/dtr (not linear!) */
1285         }
1286
1287         /* Convert step rate from microseconds to milliseconds and 4 bits */
1288         srt = 16 - DIV_ROUND_UP(DP->srt * scale_dtr / 1000, NOMINAL_DTR);
1289         if (slow_floppy)
1290                 srt = srt / 4;
1291
1292         SUPBOUND(srt, 0xf);
1293         INFBOUND(srt, 0);
1294
1295         hlt = DIV_ROUND_UP(DP->hlt * scale_dtr / 2, NOMINAL_DTR);
1296         if (hlt < 0x01)
1297                 hlt = 0x01;
1298         else if (hlt > 0x7f)
1299                 hlt = hlt_max_code;
1300
1301         hut = DIV_ROUND_UP(DP->hut * scale_dtr / 16, NOMINAL_DTR);
1302         if (hut < 0x1)
1303                 hut = 0x1;
1304         else if (hut > 0xf)
1305                 hut = hut_max_code;
1306
1307         spec1 = (srt << 4) | hut;
1308         spec2 = (hlt << 1) | (use_virtual_dma & 1);
1309
1310         /* If these parameters did not change, just return with success */
1311         if (FDCS->spec1 != spec1 || FDCS->spec2 != spec2) {
1312                 /* Go ahead and set spec1 and spec2 */
1313                 output_byte(FD_SPECIFY);
1314                 output_byte(FDCS->spec1 = spec1);
1315                 output_byte(FDCS->spec2 = spec2);
1316         }
1317 }                               /* fdc_specify */
1318
1319 /* Set the FDC's data transfer rate on behalf of the specified drive.
1320  * NOTE: with 82072/82077 FDCs, changing the data rate requires a reissue
1321  * of the specify command (i.e. using the fdc_specify function).
1322  */
1323 static int fdc_dtr(void)
1324 {
1325         /* If data rate not already set to desired value, set it. */
1326         if ((raw_cmd->rate & 3) == FDCS->dtr)
1327                 return 0;
1328
1329         /* Set dtr */
1330         fd_outb(raw_cmd->rate & 3, FD_DCR);
1331
1332         /* TODO: some FDC/drive combinations (C&T 82C711 with TEAC 1.2MB)
1333          * need a stabilization period of several milliseconds to be
1334          * enforced after data rate changes before R/W operations.
1335          * Pause 5 msec to avoid trouble. (Needs to be 2 jiffies)
1336          */
1337         FDCS->dtr = raw_cmd->rate & 3;
1338         return fd_wait_for_completion(jiffies + 2UL * HZ / 100,
1339                                       (work_func_t)floppy_ready);
1340 }                               /* fdc_dtr */
1341
1342 static void tell_sector(void)
1343 {
1344         pr_cont(": track %d, head %d, sector %d, size %d",
1345                 R_TRACK, R_HEAD, R_SECTOR, R_SIZECODE);
1346 }                               /* tell_sector */
1347
1348 static void print_errors(void)
1349 {
1350         DPRINT("");
1351         if (ST0 & ST0_ECE) {
1352                 pr_cont("Recalibrate failed!");
1353         } else if (ST2 & ST2_CRC) {
1354                 pr_cont("data CRC error");
1355                 tell_sector();
1356         } else if (ST1 & ST1_CRC) {
1357                 pr_cont("CRC error");
1358                 tell_sector();
1359         } else if ((ST1 & (ST1_MAM | ST1_ND)) ||
1360                    (ST2 & ST2_MAM)) {
1361                 if (!probing) {
1362                         pr_cont("sector not found");
1363                         tell_sector();
1364                 } else
1365                         pr_cont("probe failed...");
1366         } else if (ST2 & ST2_WC) {      /* seek error */
1367                 pr_cont("wrong cylinder");
1368         } else if (ST2 & ST2_BC) {      /* cylinder marked as bad */
1369                 pr_cont("bad cylinder");
1370         } else {
1371                 pr_cont("unknown error. ST[0..2] are: 0x%x 0x%x 0x%x",
1372                         ST0, ST1, ST2);
1373                 tell_sector();
1374         }
1375         pr_cont("\n");
1376 }
1377
1378 /*
1379  * OK, this error interpreting routine is called after a
1380  * DMA read/write has succeeded
1381  * or failed, so we check the results, and copy any buffers.
1382  * hhb: Added better error reporting.
1383  * ak: Made this into a separate routine.
1384  */
1385 static int interpret_errors(void)
1386 {
1387         char bad;
1388
1389         if (inr != 7) {
1390                 DPRINT("-- FDC reply error\n");
1391                 FDCS->reset = 1;
1392                 return 1;
1393         }
1394
1395         /* check IC to find cause of interrupt */
1396         switch (ST0 & ST0_INTR) {
1397         case 0x40:              /* error occurred during command execution */
1398                 if (ST1 & ST1_EOC)
1399                         return 0;       /* occurs with pseudo-DMA */
1400                 bad = 1;
1401                 if (ST1 & ST1_WP) {
1402                         DPRINT("Drive is write protected\n");
1403                         clear_bit(FD_DISK_WRITABLE_BIT, &DRS->flags);
1404                         cont->done(0);
1405                         bad = 2;
1406                 } else if (ST1 & ST1_ND) {
1407                         set_bit(FD_NEED_TWADDLE_BIT, &DRS->flags);
1408                 } else if (ST1 & ST1_OR) {
1409                         if (DP->flags & FTD_MSG)
1410                                 DPRINT("Over/Underrun - retrying\n");
1411                         bad = 0;
1412                 } else if (*errors >= DP->max_errors.reporting) {
1413                         print_errors();
1414                 }
1415                 if (ST2 & ST2_WC || ST2 & ST2_BC)
1416                         /* wrong cylinder => recal */
1417                         DRS->track = NEED_2_RECAL;
1418                 return bad;
1419         case 0x80:              /* invalid command given */
1420                 DPRINT("Invalid FDC command given!\n");
1421                 cont->done(0);
1422                 return 2;
1423         case 0xc0:
1424                 DPRINT("Abnormal termination caused by polling\n");
1425                 cont->error();
1426                 return 2;
1427         default:                /* (0) Normal command termination */
1428                 return 0;
1429         }
1430 }
1431
1432 /*
1433  * This routine is called when everything should be correctly set up
1434  * for the transfer (i.e. floppy motor is on, the correct floppy is
1435  * selected, and the head is sitting on the right track).
1436  */
1437 static void setup_rw_floppy(void)
1438 {
1439         int i;
1440         int r;
1441         int flags;
1442         int dflags;
1443         unsigned long ready_date;
1444         work_func_t function;
1445
1446         flags = raw_cmd->flags;
1447         if (flags & (FD_RAW_READ | FD_RAW_WRITE))
1448                 flags |= FD_RAW_INTR;
1449
1450         if ((flags & FD_RAW_SPIN) && !(flags & FD_RAW_NO_MOTOR)) {
1451                 ready_date = DRS->spinup_date + DP->spinup;
1452                 /* If spinup will take a long time, rerun scandrives
1453                  * again just before spinup completion. Beware that
1454                  * after scandrives, we must again wait for selection.
1455                  */
1456                 if (time_after(ready_date, jiffies + DP->select_delay)) {
1457                         ready_date -= DP->select_delay;
1458                         function = (work_func_t)floppy_start;
1459                 } else
1460                         function = (work_func_t)setup_rw_floppy;
1461
1462                 /* wait until the floppy is spinning fast enough */
1463                 if (fd_wait_for_completion(ready_date, function))
1464                         return;
1465         }
1466         dflags = DRS->flags;
1467
1468         if ((flags & FD_RAW_READ) || (flags & FD_RAW_WRITE))
1469                 setup_DMA();
1470
1471         if (flags & FD_RAW_INTR)
1472                 do_floppy = main_command_interrupt;
1473
1474         r = 0;
1475         for (i = 0; i < raw_cmd->cmd_count; i++)
1476                 r |= output_byte(raw_cmd->cmd[i]);
1477
1478         debugt(__func__, "rw_command");
1479
1480         if (r) {
1481                 cont->error();
1482                 reset_fdc();
1483                 return;
1484         }
1485
1486         if (!(flags & FD_RAW_INTR)) {
1487                 inr = result();
1488                 cont->interrupt();
1489         } else if (flags & FD_RAW_NEED_DISK)
1490                 fd_watchdog(NULL);
1491 }
1492
1493 static int blind_seek;
1494
1495 /*
1496  * This is the routine called after every seek (or recalibrate) interrupt
1497  * from the floppy controller.
1498  */
1499 static void seek_interrupt(void)
1500 {
1501         debugt(__func__, "");
1502         if (inr != 2 || (ST0 & 0xF8) != 0x20) {
1503                 DPRINT("seek failed\n");
1504                 DRS->track = NEED_2_RECAL;
1505                 cont->error();
1506                 cont->redo();
1507                 return;
1508         }
1509         if (DRS->track >= 0 && DRS->track != ST1 && !blind_seek) {
1510                 debug_dcl(DP->flags,
1511                           "clearing NEWCHANGE flag because of effective seek\n");
1512                 debug_dcl(DP->flags, "jiffies=%lu\n", jiffies);
1513                 clear_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags);
1514                                         /* effective seek */
1515                 DRS->select_date = jiffies;
1516         }
1517         DRS->track = ST1;
1518         floppy_ready();
1519 }
1520
1521 static void check_wp(void)
1522 {
1523         if (test_bit(FD_VERIFY_BIT, &DRS->flags)) {
1524                                         /* check write protection */
1525                 output_byte(FD_GETSTATUS);
1526                 output_byte(UNIT(current_drive));
1527                 if (result() != 1) {
1528                         FDCS->reset = 1;
1529                         return;
1530                 }
1531                 clear_bit(FD_VERIFY_BIT, &DRS->flags);
1532                 clear_bit(FD_NEED_TWADDLE_BIT, &DRS->flags);
1533                 debug_dcl(DP->flags,
1534                           "checking whether disk is write protected\n");
1535                 debug_dcl(DP->flags, "wp=%x\n", ST3 & 0x40);
1536                 if (!(ST3 & 0x40))
1537                         set_bit(FD_DISK_WRITABLE_BIT, &DRS->flags);
1538                 else
1539                         clear_bit(FD_DISK_WRITABLE_BIT, &DRS->flags);
1540         }
1541 }
1542
1543 static void seek_floppy(void)
1544 {
1545         int track;
1546
1547         blind_seek = 0;
1548
1549         debug_dcl(DP->flags, "calling disk change from %s\n", __func__);
1550
1551         if (!test_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags) &&
1552             disk_change(current_drive) && (raw_cmd->flags & FD_RAW_NEED_DISK)) {
1553                 /* the media changed flag should be cleared after the seek.
1554                  * If it isn't, this means that there is really no disk in
1555                  * the drive.
1556                  */
1557                 set_bit(FD_DISK_CHANGED_BIT, &DRS->flags);
1558                 cont->done(0);
1559                 cont->redo();
1560                 return;
1561         }
1562         if (DRS->track <= NEED_1_RECAL) {
1563                 recalibrate_floppy();
1564                 return;
1565         } else if (test_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags) &&
1566                    (raw_cmd->flags & FD_RAW_NEED_DISK) &&
1567                    (DRS->track <= NO_TRACK || DRS->track == raw_cmd->track)) {
1568                 /* we seek to clear the media-changed condition. Does anybody
1569                  * know a more elegant way, which works on all drives? */
1570                 if (raw_cmd->track)
1571                         track = raw_cmd->track - 1;
1572                 else {
1573                         if (DP->flags & FD_SILENT_DCL_CLEAR) {
1574                                 set_dor(fdc, ~(0x10 << UNIT(current_drive)), 0);
1575                                 blind_seek = 1;
1576                                 raw_cmd->flags |= FD_RAW_NEED_SEEK;
1577                         }
1578                         track = 1;
1579                 }
1580         } else {
1581                 check_wp();
1582                 if (raw_cmd->track != DRS->track &&
1583                     (raw_cmd->flags & FD_RAW_NEED_SEEK))
1584                         track = raw_cmd->track;
1585                 else {
1586                         setup_rw_floppy();
1587                         return;
1588                 }
1589         }
1590
1591         do_floppy = seek_interrupt;
1592         output_byte(FD_SEEK);
1593         output_byte(UNIT(current_drive));
1594         if (output_byte(track) < 0) {
1595                 reset_fdc();
1596                 return;
1597         }
1598         debugt(__func__, "");
1599 }
1600
1601 static void recal_interrupt(void)
1602 {
1603         debugt(__func__, "");
1604         if (inr != 2)
1605                 FDCS->reset = 1;
1606         else if (ST0 & ST0_ECE) {
1607                 switch (DRS->track) {
1608                 case NEED_1_RECAL:
1609                         debugt(__func__, "need 1 recal");
1610                         /* after a second recalibrate, we still haven't
1611                          * reached track 0. Probably no drive. Raise an
1612                          * error, as failing immediately might upset
1613                          * computers possessed by the Devil :-) */
1614                         cont->error();
1615                         cont->redo();
1616                         return;
1617                 case NEED_2_RECAL:
1618                         debugt(__func__, "need 2 recal");
1619                         /* If we already did a recalibrate,
1620                          * and we are not at track 0, this
1621                          * means we have moved. (The only way
1622                          * not to move at recalibration is to
1623                          * be already at track 0.) Clear the
1624                          * new change flag */
1625                         debug_dcl(DP->flags,
1626                                   "clearing NEWCHANGE flag because of second recalibrate\n");
1627
1628                         clear_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags);
1629                         DRS->select_date = jiffies;
1630                         /* fall through */
1631                 default:
1632                         debugt(__func__, "default");
1633                         /* Recalibrate moves the head by at
1634                          * most 80 steps. If after one
1635                          * recalibrate we don't have reached
1636                          * track 0, this might mean that we
1637                          * started beyond track 80.  Try
1638                          * again.  */
1639                         DRS->track = NEED_1_RECAL;
1640                         break;
1641                 }
1642         } else
1643                 DRS->track = ST1;
1644         floppy_ready();
1645 }
1646
1647 static void print_result(char *message, int inr)
1648 {
1649         int i;
1650
1651         DPRINT("%s ", message);
1652         if (inr >= 0)
1653                 for (i = 0; i < inr; i++)
1654                         pr_cont("repl[%d]=%x ", i, reply_buffer[i]);
1655         pr_cont("\n");
1656 }
1657
1658 /* interrupt handler. Note that this can be called externally on the Sparc */
1659 irqreturn_t floppy_interrupt(int irq, void *dev_id)
1660 {
1661         int do_print;
1662         unsigned long f;
1663         void (*handler)(void) = do_floppy;
1664
1665         lasthandler = handler;
1666         interruptjiffies = jiffies;
1667
1668         f = claim_dma_lock();
1669         fd_disable_dma();
1670         release_dma_lock(f);
1671
1672         do_floppy = NULL;
1673         if (fdc >= N_FDC || FDCS->address == -1) {
1674                 /* we don't even know which FDC is the culprit */
1675                 pr_info("DOR0=%x\n", fdc_state[0].dor);
1676                 pr_info("floppy interrupt on bizarre fdc %d\n", fdc);
1677                 pr_info("handler=%pf\n", handler);
1678                 is_alive(__func__, "bizarre fdc");
1679                 return IRQ_NONE;
1680         }
1681
1682         FDCS->reset = 0;
1683         /* We have to clear the reset flag here, because apparently on boxes
1684          * with level triggered interrupts (PS/2, Sparc, ...), it is needed to
1685          * emit SENSEI's to clear the interrupt line. And FDCS->reset blocks the
1686          * emission of the SENSEI's.
1687          * It is OK to emit floppy commands because we are in an interrupt
1688          * handler here, and thus we have to fear no interference of other
1689          * activity.
1690          */
1691
1692         do_print = !handler && print_unex && initialized;
1693
1694         inr = result();
1695         if (do_print)
1696                 print_result("unexpected interrupt", inr);
1697         if (inr == 0) {
1698                 int max_sensei = 4;
1699                 do {
1700                         output_byte(FD_SENSEI);
1701                         inr = result();
1702                         if (do_print)
1703                                 print_result("sensei", inr);
1704                         max_sensei--;
1705                 } while ((ST0 & 0x83) != UNIT(current_drive) &&
1706                          inr == 2 && max_sensei);
1707         }
1708         if (!handler) {
1709                 FDCS->reset = 1;
1710                 return IRQ_NONE;
1711         }
1712         schedule_bh(handler);
1713         is_alive(__func__, "normal interrupt end");
1714
1715         /* FIXME! Was it really for us? */
1716         return IRQ_HANDLED;
1717 }
1718
1719 static void recalibrate_floppy(void)
1720 {
1721         debugt(__func__, "");
1722         do_floppy = recal_interrupt;
1723         output_byte(FD_RECALIBRATE);
1724         if (output_byte(UNIT(current_drive)) < 0)
1725                 reset_fdc();
1726 }
1727
1728 /*
1729  * Must do 4 FD_SENSEIs after reset because of ``drive polling''.
1730  */
1731 static void reset_interrupt(void)
1732 {
1733         debugt(__func__, "");
1734         result();               /* get the status ready for set_fdc */
1735         if (FDCS->reset) {
1736                 pr_info("reset set in interrupt, calling %pf\n", cont->error);
1737                 cont->error();  /* a reset just after a reset. BAD! */
1738         }
1739         cont->redo();
1740 }
1741
1742 /*
1743  * reset is done by pulling bit 2 of DOR low for a while (old FDCs),
1744  * or by setting the self clearing bit 7 of STATUS (newer FDCs)
1745  */
1746 static void reset_fdc(void)
1747 {
1748         unsigned long flags;
1749
1750         do_floppy = reset_interrupt;
1751         FDCS->reset = 0;
1752         reset_fdc_info(0);
1753
1754         /* Pseudo-DMA may intercept 'reset finished' interrupt.  */
1755         /* Irrelevant for systems with true DMA (i386).          */
1756
1757         flags = claim_dma_lock();
1758         fd_disable_dma();
1759         release_dma_lock(flags);
1760
1761         if (FDCS->version >= FDC_82072A)
1762                 fd_outb(0x80 | (FDCS->dtr & 3), FD_STATUS);
1763         else {
1764                 fd_outb(FDCS->dor & ~0x04, FD_DOR);
1765                 udelay(FD_RESET_DELAY);
1766                 fd_outb(FDCS->dor, FD_DOR);
1767         }
1768 }
1769
1770 static void show_floppy(void)
1771 {
1772         int i;
1773
1774         pr_info("\n");
1775         pr_info("floppy driver state\n");
1776         pr_info("-------------------\n");
1777         pr_info("now=%lu last interrupt=%lu diff=%lu last called handler=%pf\n",
1778                 jiffies, interruptjiffies, jiffies - interruptjiffies,
1779                 lasthandler);
1780
1781         pr_info("timeout_message=%s\n", timeout_message);
1782         pr_info("last output bytes:\n");
1783         for (i = 0; i < OLOGSIZE; i++)
1784                 pr_info("%2x %2x %lu\n",
1785                         output_log[(i + output_log_pos) % OLOGSIZE].data,
1786                         output_log[(i + output_log_pos) % OLOGSIZE].status,
1787                         output_log[(i + output_log_pos) % OLOGSIZE].jiffies);
1788         pr_info("last result at %lu\n", resultjiffies);
1789         pr_info("last redo_fd_request at %lu\n", lastredo);
1790         print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE, 16, 1,
1791                        reply_buffer, resultsize, true);
1792
1793         pr_info("status=%x\n", fd_inb(FD_STATUS));
1794         pr_info("fdc_busy=%lu\n", fdc_busy);
1795         if (do_floppy)
1796                 pr_info("do_floppy=%pf\n", do_floppy);
1797         if (work_pending(&floppy_work))
1798                 pr_info("floppy_work.func=%pf\n", floppy_work.func);
1799         if (delayed_work_pending(&fd_timer))
1800                 pr_info("delayed work.function=%p expires=%ld\n",
1801                        fd_timer.work.func,
1802                        fd_timer.timer.expires - jiffies);
1803         if (delayed_work_pending(&fd_timeout))
1804                 pr_info("timer_function=%p expires=%ld\n",
1805                        fd_timeout.work.func,
1806                        fd_timeout.timer.expires - jiffies);
1807
1808         pr_info("cont=%p\n", cont);
1809         pr_info("current_req=%p\n", current_req);
1810         pr_info("command_status=%d\n", command_status);
1811         pr_info("\n");
1812 }
1813
1814 static void floppy_shutdown(struct work_struct *arg)
1815 {
1816         unsigned long flags;
1817
1818         if (initialized)
1819                 show_floppy();
1820         cancel_activity();
1821
1822         flags = claim_dma_lock();
1823         fd_disable_dma();
1824         release_dma_lock(flags);
1825
1826         /* avoid dma going to a random drive after shutdown */
1827
1828         if (initialized)
1829                 DPRINT("floppy timeout called\n");
1830         FDCS->reset = 1;
1831         if (cont) {
1832                 cont->done(0);
1833                 cont->redo();   /* this will recall reset when needed */
1834         } else {
1835                 pr_info("no cont in shutdown!\n");
1836                 process_fd_request();
1837         }
1838         is_alive(__func__, "");
1839 }
1840
1841 /* start motor, check media-changed condition and write protection */
1842 static int start_motor(void (*function)(void))
1843 {
1844         int mask;
1845         int data;
1846
1847         mask = 0xfc;
1848         data = UNIT(current_drive);
1849         if (!(raw_cmd->flags & FD_RAW_NO_MOTOR)) {
1850                 if (!(FDCS->dor & (0x10 << UNIT(current_drive)))) {
1851                         set_debugt();
1852                         /* no read since this drive is running */
1853                         DRS->first_read_date = 0;
1854                         /* note motor start time if motor is not yet running */
1855                         DRS->spinup_date = jiffies;
1856                         data |= (0x10 << UNIT(current_drive));
1857                 }
1858         } else if (FDCS->dor & (0x10 << UNIT(current_drive)))
1859                 mask &= ~(0x10 << UNIT(current_drive));
1860
1861         /* starts motor and selects floppy */
1862         del_timer(motor_off_timer + current_drive);
1863         set_dor(fdc, mask, data);
1864
1865         /* wait_for_completion also schedules reset if needed. */
1866         return fd_wait_for_completion(DRS->select_date + DP->select_delay,
1867                                       (work_func_t)function);
1868 }
1869
1870 static void floppy_ready(void)
1871 {
1872         if (FDCS->reset) {
1873                 reset_fdc();
1874                 return;
1875         }
1876         if (start_motor(floppy_ready))
1877                 return;
1878         if (fdc_dtr())
1879                 return;
1880
1881         debug_dcl(DP->flags, "calling disk change from floppy_ready\n");
1882         if (!(raw_cmd->flags & FD_RAW_NO_MOTOR) &&
1883             disk_change(current_drive) && !DP->select_delay)
1884                 twaddle();      /* this clears the dcl on certain
1885                                  * drive/controller combinations */
1886
1887 #ifdef fd_chose_dma_mode
1888         if ((raw_cmd->flags & FD_RAW_READ) || (raw_cmd->flags & FD_RAW_WRITE)) {
1889                 unsigned long flags = claim_dma_lock();
1890                 fd_chose_dma_mode(raw_cmd->kernel_data, raw_cmd->length);
1891                 release_dma_lock(flags);
1892         }
1893 #endif
1894
1895         if (raw_cmd->flags & (FD_RAW_NEED_SEEK | FD_RAW_NEED_DISK)) {
1896                 perpendicular_mode();
1897                 fdc_specify();  /* must be done here because of hut, hlt ... */
1898                 seek_floppy();
1899         } else {
1900                 if ((raw_cmd->flags & FD_RAW_READ) ||
1901                     (raw_cmd->flags & FD_RAW_WRITE))
1902                         fdc_specify();
1903                 setup_rw_floppy();
1904         }
1905 }
1906
1907 static void floppy_start(void)
1908 {
1909         reschedule_timeout(current_reqD, "floppy start");
1910
1911         scandrives();
1912         debug_dcl(DP->flags, "setting NEWCHANGE in floppy_start\n");
1913         set_bit(FD_DISK_NEWCHANGE_BIT, &DRS->flags);
1914         floppy_ready();
1915 }
1916
1917 /*
1918  * ========================================================================
1919  * here ends the bottom half. Exported routines are:
1920  * floppy_start, floppy_off, floppy_ready, lock_fdc, unlock_fdc, set_fdc,
1921  * start_motor, reset_fdc, reset_fdc_info, interpret_errors.
1922  * Initialization also uses output_byte, result, set_dor, floppy_interrupt
1923  * and set_dor.
1924  * ========================================================================
1925  */
1926 /*
1927  * General purpose continuations.
1928  * ==============================
1929  */
1930
1931 static void do_wakeup(void)
1932 {
1933         reschedule_timeout(MAXTIMEOUT, "do wakeup");
1934         cont = NULL;
1935         command_status += 2;
1936         wake_up(&command_done);
1937 }
1938
1939 static const struct cont_t wakeup_cont = {
1940         .interrupt      = empty,
1941         .redo           = do_wakeup,
1942         .error          = empty,
1943         .done           = (done_f)empty
1944 };
1945
1946 static const struct cont_t intr_cont = {
1947         .interrupt      = empty,
1948         .redo           = process_fd_request,
1949         .error          = empty,
1950         .done           = (done_f)empty
1951 };
1952
1953 static int wait_til_done(void (*handler)(void), bool interruptible)
1954 {
1955         int ret;
1956
1957         schedule_bh(handler);
1958
1959         if (interruptible)
1960                 wait_event_interruptible(command_done, command_status >= 2);
1961         else
1962                 wait_event(command_done, command_status >= 2);
1963
1964         if (command_status < 2) {
1965                 cancel_activity();
1966                 cont = &intr_cont;
1967                 reset_fdc();
1968                 return -EINTR;
1969         }
1970
1971         if (FDCS->reset)
1972                 command_status = FD_COMMAND_ERROR;
1973         if (command_status == FD_COMMAND_OKAY)
1974                 ret = 0;
1975         else
1976                 ret = -EIO;
1977         command_status = FD_COMMAND_NONE;
1978         return ret;
1979 }
1980
1981 static void generic_done(int result)
1982 {
1983         command_status = result;
1984         cont = &wakeup_cont;
1985 }
1986
1987 static void generic_success(void)
1988 {
1989         cont->done(1);
1990 }
1991
1992 static void generic_failure(void)
1993 {
1994         cont->done(0);
1995 }
1996
1997 static void success_and_wakeup(void)
1998 {
1999         generic_success();
2000         cont->redo();
2001 }
2002
2003 /*
2004  * formatting and rw support.
2005  * ==========================
2006  */
2007
2008 static int next_valid_format(void)
2009 {
2010         int probed_format;
2011
2012         probed_format = DRS->probed_format;
2013         while (1) {
2014                 if (probed_format >= 8 || !DP->autodetect[probed_format]) {
2015                         DRS->probed_format = 0;
2016                         return 1;
2017                 }
2018                 if (floppy_type[DP->autodetect[probed_format]].sect) {
2019                         DRS->probed_format = probed_format;
2020                         return 0;
2021                 }
2022                 probed_format++;
2023         }
2024 }
2025
2026 static void bad_flp_intr(void)
2027 {
2028         int err_count;
2029
2030         if (probing) {
2031                 DRS->probed_format++;
2032                 if (!next_valid_format())
2033                         return;
2034         }
2035         err_count = ++(*errors);
2036         INFBOUND(DRWE->badness, err_count);
2037         if (err_count > DP->max_errors.abort)
2038                 cont->done(0);
2039         if (err_count > DP->max_errors.reset)
2040                 FDCS->reset = 1;
2041         else if (err_count > DP->max_errors.recal)
2042                 DRS->track = NEED_2_RECAL;
2043 }
2044
2045 static void set_floppy(int drive)
2046 {
2047         int type = ITYPE(UDRS->fd_device);
2048
2049         if (type)
2050                 _floppy = floppy_type + type;
2051         else
2052                 _floppy = current_type[drive];
2053 }
2054
2055 /*
2056  * formatting support.
2057  * ===================
2058  */
2059 static void format_interrupt(void)
2060 {
2061         switch (interpret_errors()) {
2062         case 1:
2063                 cont->error();
2064         case 2:
2065                 break;
2066         case 0:
2067                 cont->done(1);
2068         }
2069         cont->redo();
2070 }
2071
2072 #define FM_MODE(x, y) ((y) & ~(((x)->rate & 0x80) >> 1))
2073 #define CT(x) ((x) | 0xc0)
2074
2075 static void setup_format_params(int track)
2076 {
2077         int n;
2078         int il;
2079         int count;
2080         int head_shift;
2081         int track_shift;
2082         struct fparm {
2083                 unsigned char track, head, sect, size;
2084         } *here = (struct fparm *)floppy_track_buffer;
2085
2086         raw_cmd = &default_raw_cmd;
2087         raw_cmd->track = track;
2088
2089         raw_cmd->flags = (FD_RAW_WRITE | FD_RAW_INTR | FD_RAW_SPIN |
2090                           FD_RAW_NEED_DISK | FD_RAW_NEED_SEEK);
2091         raw_cmd->rate = _floppy->rate & 0x43;
2092         raw_cmd->cmd_count = NR_F;
2093         COMMAND = FM_MODE(_floppy, FD_FORMAT);
2094         DR_SELECT = UNIT(current_drive) + PH_HEAD(_floppy, format_req.head);
2095         F_SIZECODE = FD_SIZECODE(_floppy);
2096         F_SECT_PER_TRACK = _floppy->sect << 2 >> F_SIZECODE;
2097         F_GAP = _floppy->fmt_gap;
2098         F_FILL = FD_FILL_BYTE;
2099
2100         raw_cmd->kernel_data = floppy_track_buffer;
2101         raw_cmd->length = 4 * F_SECT_PER_TRACK;
2102
2103         /* allow for about 30ms for data transport per track */
2104         head_shift = (F_SECT_PER_TRACK + 5) / 6;
2105
2106         /* a ``cylinder'' is two tracks plus a little stepping time */
2107         track_shift = 2 * head_shift + 3;
2108
2109         /* position of logical sector 1 on this track */
2110         n = (track_shift * format_req.track + head_shift * format_req.head)
2111             % F_SECT_PER_TRACK;
2112
2113         /* determine interleave */
2114         il = 1;
2115         if (_floppy->fmt_gap < 0x22)
2116                 il++;
2117
2118         /* initialize field */
2119         for (count = 0; count < F_SECT_PER_TRACK; ++count) {
2120                 here[count].track = format_req.track;
2121                 here[count].head = format_req.head;
2122                 here[count].sect = 0;
2123                 here[count].size = F_SIZECODE;
2124         }
2125         /* place logical sectors */
2126         for (count = 1; count <= F_SECT_PER_TRACK; ++count) {
2127                 here[n].sect = count;
2128                 n = (n + il) % F_SECT_PER_TRACK;
2129                 if (here[n].sect) {     /* sector busy, find next free sector */
2130                         ++n;
2131                         if (n >= F_SECT_PER_TRACK) {
2132                                 n -= F_SECT_PER_TRACK;
2133                                 while (here[n].sect)
2134                                         ++n;
2135                         }
2136                 }
2137         }
2138         if (_floppy->stretch & FD_SECTBASEMASK) {
2139                 for (count = 0; count < F_SECT_PER_TRACK; count++)
2140                         here[count].sect += FD_SECTBASE(_floppy) - 1;
2141         }
2142 }
2143
2144 static void redo_format(void)
2145 {
2146         buffer_track = -1;
2147         setup_format_params(format_req.track << STRETCH(_floppy));
2148         floppy_start();
2149         debugt(__func__, "queue format request");
2150 }
2151
2152 static const struct cont_t format_cont = {
2153         .interrupt      = format_interrupt,
2154         .redo           = redo_format,
2155         .error          = bad_flp_intr,
2156         .done           = generic_done
2157 };
2158
2159 static int do_format(int drive, struct format_descr *tmp_format_req)
2160 {
2161         int ret;
2162
2163         if (lock_fdc(drive, true))
2164                 return -EINTR;
2165
2166         set_floppy(drive);
2167         if (!_floppy ||
2168             _floppy->track > DP->tracks ||
2169             tmp_format_req->track >= _floppy->track ||
2170             tmp_format_req->head >= _floppy->head ||
2171             (_floppy->sect << 2) % (1 << FD_SIZECODE(_floppy)) ||
2172             !_floppy->fmt_gap) {
2173                 process_fd_request();
2174                 return -EINVAL;
2175         }
2176         format_req = *tmp_format_req;
2177         format_errors = 0;
2178         cont = &format_cont;
2179         errors = &format_errors;
2180         ret = wait_til_done(redo_format, true);
2181         if (ret == -EINTR)
2182                 return -EINTR;
2183         process_fd_request();
2184         return ret;
2185 }
2186
2187 /*
2188  * Buffer read/write and support
2189  * =============================
2190  */
2191
2192 static void floppy_end_request(struct request *req, int error)
2193 {
2194         unsigned int nr_sectors = current_count_sectors;
2195         unsigned int drive = (unsigned long)req->rq_disk->private_data;
2196
2197         /* current_count_sectors can be zero if transfer failed */
2198         if (error)
2199                 nr_sectors = blk_rq_cur_sectors(req);
2200         if (__blk_end_request(req, error, nr_sectors << 9))
2201                 return;
2202
2203         /* We're done with the request */
2204         floppy_off(drive);
2205         current_req = NULL;
2206 }
2207
2208 /* new request_done. Can handle physical sectors which are smaller than a
2209  * logical buffer */
2210 static void request_done(int uptodate)
2211 {
2212         struct request *req = current_req;
2213         struct request_queue *q;
2214         unsigned long flags;
2215         int block;
2216         char msg[sizeof("request done ") + sizeof(int) * 3];
2217
2218         probing = 0;
2219         snprintf(msg, sizeof(msg), "request done %d", uptodate);
2220         reschedule_timeout(MAXTIMEOUT, msg);
2221
2222         if (!req) {
2223                 pr_info("floppy.c: no request in request_done\n");
2224                 return;
2225         }
2226
2227         q = req->q;
2228
2229         if (uptodate) {
2230                 /* maintain values for invalidation on geometry
2231                  * change */
2232                 block = current_count_sectors + blk_rq_pos(req);
2233                 INFBOUND(DRS->maxblock, block);
2234                 if (block > _floppy->sect)
2235                         DRS->maxtrack = 1;
2236
2237                 /* unlock chained buffers */
2238                 spin_lock_irqsave(q->queue_lock, flags);
2239                 floppy_end_request(req, 0);
2240                 spin_unlock_irqrestore(q->queue_lock, flags);
2241         } else {
2242                 if (rq_data_dir(req) == WRITE) {
2243                         /* record write error information */
2244                         DRWE->write_errors++;
2245                         if (DRWE->write_errors == 1) {
2246                                 DRWE->first_error_sector = blk_rq_pos(req);
2247                                 DRWE->first_error_generation = DRS->generation;
2248                         }
2249                         DRWE->last_error_sector = blk_rq_pos(req);
2250                         DRWE->last_error_generation = DRS->generation;
2251                 }
2252                 spin_lock_irqsave(q->queue_lock, flags);
2253                 floppy_end_request(req, -EIO);
2254                 spin_unlock_irqrestore(q->queue_lock, flags);
2255         }
2256 }
2257
2258 /* Interrupt handler evaluating the result of the r/w operation */
2259 static void rw_interrupt(void)
2260 {
2261         int eoc;
2262         int ssize;
2263         int heads;
2264         int nr_sectors;
2265
2266         if (R_HEAD >= 2) {
2267                 /* some Toshiba floppy controllers occasionnally seem to
2268                  * return bogus interrupts after read/write operations, which
2269                  * can be recognized by a bad head number (>= 2) */
2270                 return;
2271         }
2272
2273         if (!DRS->first_read_date)
2274                 DRS->first_read_date = jiffies;
2275
2276         nr_sectors = 0;
2277         ssize = DIV_ROUND_UP(1 << SIZECODE, 4);
2278
2279         if (ST1 & ST1_EOC)
2280                 eoc = 1;
2281         else
2282                 eoc = 0;
2283
2284         if (COMMAND & 0x80)
2285                 heads = 2;
2286         else
2287                 heads = 1;
2288
2289         nr_sectors = (((R_TRACK - TRACK) * heads +
2290                        R_HEAD - HEAD) * SECT_PER_TRACK +
2291                       R_SECTOR - SECTOR + eoc) << SIZECODE >> 2;
2292
2293         if (nr_sectors / ssize >
2294             DIV_ROUND_UP(in_sector_offset + current_count_sectors, ssize)) {
2295                 DPRINT("long rw: %x instead of %lx\n",
2296                        nr_sectors, current_count_sectors);
2297                 pr_info("rs=%d s=%d\n", R_SECTOR, SECTOR);
2298                 pr_info("rh=%d h=%d\n", R_HEAD, HEAD);
2299                 pr_info("rt=%d t=%d\n", R_TRACK, TRACK);
2300                 pr_info("heads=%d eoc=%d\n", heads, eoc);
2301                 pr_info("spt=%d st=%d ss=%d\n",
2302                         SECT_PER_TRACK, fsector_t, ssize);
2303                 pr_info("in_sector_offset=%d\n", in_sector_offset);
2304         }
2305
2306         nr_sectors -= in_sector_offset;
2307         INFBOUND(nr_sectors, 0);
2308         SUPBOUND(current_count_sectors, nr_sectors);
2309
2310         switch (interpret_errors()) {
2311         case 2:
2312                 cont->redo();
2313                 return;
2314         case 1:
2315                 if (!current_count_sectors) {
2316                         cont->error();
2317                         cont->redo();
2318                         return;
2319                 }
2320                 break;
2321         case 0:
2322                 if (!current_count_sectors) {
2323                         cont->redo();
2324                         return;
2325                 }
2326                 current_type[current_drive] = _floppy;
2327                 floppy_sizes[TOMINOR(current_drive)] = _floppy->size;
2328                 break;
2329         }
2330
2331         if (probing) {
2332                 if (DP->flags & FTD_MSG)
2333                         DPRINT("Auto-detected floppy type %s in fd%d\n",
2334                                _floppy->name, current_drive);
2335                 current_type[current_drive] = _floppy;
2336                 floppy_sizes[TOMINOR(current_drive)] = _floppy->size;
2337                 probing = 0;
2338         }
2339
2340         if (CT(COMMAND) != FD_READ ||
2341             raw_cmd->kernel_data == current_req->buffer) {
2342                 /* transfer directly from buffer */
2343                 cont->done(1);
2344         } else if (CT(COMMAND) == FD_READ) {
2345                 buffer_track = raw_cmd->track;
2346                 buffer_drive = current_drive;
2347                 INFBOUND(buffer_max, nr_sectors + fsector_t);
2348         }
2349         cont->redo();
2350 }
2351
2352 /* Compute maximal contiguous buffer size. */
2353 static int buffer_chain_size(void)
2354 {
2355         struct bio_vec *bv;
2356         int size;
2357         struct req_iterator iter;
2358         char *base;
2359
2360         base = bio_data(current_req->bio);
2361         size = 0;
2362
2363         rq_for_each_segment(bv, current_req, iter) {
2364                 if (page_address(bv->bv_page) + bv->bv_offset != base + size)
2365                         break;
2366
2367                 size += bv->bv_len;
2368         }
2369
2370         return size >> 9;
2371 }
2372
2373 /* Compute the maximal transfer size */
2374 static int transfer_size(int ssize, int max_sector, int max_size)
2375 {
2376         SUPBOUND(max_sector, fsector_t + max_size);
2377
2378         /* alignment */
2379         max_sector -= (max_sector % _floppy->sect) % ssize;
2380
2381         /* transfer size, beginning not aligned */
2382         current_count_sectors = max_sector - fsector_t;
2383
2384         return max_sector;
2385 }
2386
2387 /*
2388  * Move data from/to the track buffer to/from the buffer cache.
2389  */
2390 static void copy_buffer(int ssize, int max_sector, int max_sector_2)
2391 {
2392         int remaining;          /* number of transferred 512-byte sectors */
2393         struct bio_vec *bv;
2394         char *buffer;
2395         char *dma_buffer;
2396         int size;
2397         struct req_iterator iter;
2398
2399         max_sector = transfer_size(ssize,
2400                                    min(max_sector, max_sector_2),
2401                                    blk_rq_sectors(current_req));
2402
2403         if (current_count_sectors <= 0 && CT(COMMAND) == FD_WRITE &&
2404             buffer_max > fsector_t + blk_rq_sectors(current_req))
2405                 current_count_sectors = min_t(int, buffer_max - fsector_t,
2406                                               blk_rq_sectors(current_req));
2407
2408         remaining = current_count_sectors << 9;
2409         if (remaining > blk_rq_bytes(current_req) && CT(COMMAND) == FD_WRITE) {
2410                 DPRINT("in copy buffer\n");
2411                 pr_info("current_count_sectors=%ld\n", current_count_sectors);
2412                 pr_info("remaining=%d\n", remaining >> 9);
2413                 pr_info("current_req->nr_sectors=%u\n",
2414                         blk_rq_sectors(current_req));
2415                 pr_info("current_req->current_nr_sectors=%u\n",
2416                         blk_rq_cur_sectors(current_req));
2417                 pr_info("max_sector=%d\n", max_sector);
2418                 pr_info("ssize=%d\n", ssize);
2419         }
2420
2421         buffer_max = max(max_sector, buffer_max);
2422
2423         dma_buffer = floppy_track_buffer + ((fsector_t - buffer_min) << 9);
2424
2425         size = blk_rq_cur_bytes(current_req);
2426
2427         rq_for_each_segment(bv, current_req, iter) {
2428                 if (!remaining)
2429                         break;
2430
2431                 size = bv->bv_len;
2432                 SUPBOUND(size, remaining);
2433
2434                 buffer = page_address(bv->bv_page) + bv->bv_offset;
2435                 if (dma_buffer + size >
2436                     floppy_track_buffer + (max_buffer_sectors << 10) ||
2437                     dma_buffer < floppy_track_buffer) {
2438                         DPRINT("buffer overrun in copy buffer %d\n",
2439                                (int)((floppy_track_buffer - dma_buffer) >> 9));
2440                         pr_info("fsector_t=%d buffer_min=%d\n",
2441                                 fsector_t, buffer_min);
2442                         pr_info("current_count_sectors=%ld\n",
2443                                 current_count_sectors);
2444                         if (CT(COMMAND) == FD_READ)
2445                                 pr_info("read\n");
2446                         if (CT(COMMAND) == FD_WRITE)
2447                                 pr_info("write\n");
2448                         break;
2449                 }
2450                 if (((unsigned long)buffer) % 512)
2451                         DPRINT("%p buffer not aligned\n", buffer);
2452
2453                 if (CT(COMMAND) == FD_READ)
2454                         memcpy(buffer, dma_buffer, size);
2455                 else
2456                         memcpy(dma_buffer, buffer, size);
2457
2458                 remaining -= size;
2459                 dma_buffer += size;
2460         }
2461         if (remaining) {
2462                 if (remaining > 0)
2463                         max_sector -= remaining >> 9;
2464                 DPRINT("weirdness: remaining %d\n", remaining >> 9);
2465         }
2466 }
2467
2468 /* work around a bug in pseudo DMA
2469  * (on some FDCs) pseudo DMA does not stop when the CPU stops
2470  * sending data.  Hence we need a different way to signal the
2471  * transfer length:  We use SECT_PER_TRACK.  Unfortunately, this
2472  * does not work with MT, hence we can only transfer one head at
2473  * a time
2474  */
2475 static void virtualdmabug_workaround(void)
2476 {
2477         int hard_sectors;
2478         int end_sector;
2479
2480         if (CT(COMMAND) == FD_WRITE) {
2481                 COMMAND &= ~0x80;       /* switch off multiple track mode */
2482
2483                 hard_sectors = raw_cmd->length >> (7 + SIZECODE);
2484                 end_sector = SECTOR + hard_sectors - 1;
2485                 if (end_sector > SECT_PER_TRACK) {
2486                         pr_info("too many sectors %d > %d\n",
2487                                 end_sector, SECT_PER_TRACK);
2488                         return;
2489                 }
2490                 SECT_PER_TRACK = end_sector;
2491                                         /* make sure SECT_PER_TRACK
2492                                          * points to end of transfer */
2493         }
2494 }
2495
2496 /*
2497  * Formulate a read/write request.
2498  * this routine decides where to load the data (directly to buffer, or to
2499  * tmp floppy area), how much data to load (the size of the buffer, the whole
2500  * track, or a single sector)
2501  * All floppy_track_buffer handling goes in here. If we ever add track buffer
2502  * allocation on the fly, it should be done here. No other part should need
2503  * modification.
2504  */
2505
2506 static int make_raw_rw_request(void)
2507 {
2508         int aligned_sector_t;
2509         int max_sector;
2510         int max_size;
2511         int tracksize;
2512         int ssize;
2513
2514         if (WARN(max_buffer_sectors == 0, "VFS: Block I/O scheduled on unopened device\n"))
2515                 return 0;
2516
2517         set_fdc((long)current_req->rq_disk->private_data);
2518
2519         raw_cmd = &default_raw_cmd;
2520         raw_cmd->flags = FD_RAW_SPIN | FD_RAW_NEED_DISK | FD_RAW_NEED_SEEK;
2521         raw_cmd->cmd_count = NR_RW;
2522         if (rq_data_dir(current_req) == READ) {
2523                 raw_cmd->flags |= FD_RAW_READ;
2524                 COMMAND = FM_MODE(_floppy, FD_READ);
2525         } else if (rq_data_dir(current_req) == WRITE) {
2526                 raw_cmd->flags |= FD_RAW_WRITE;
2527                 COMMAND = FM_MODE(_floppy, FD_WRITE);
2528         } else {
2529                 DPRINT("%s: unknown command\n", __func__);
2530                 return 0;
2531         }
2532
2533         max_sector = _floppy->sect * _floppy->head;
2534
2535         TRACK = (int)blk_rq_pos(current_req) / max_sector;
2536         fsector_t = (int)blk_rq_pos(current_req) % max_sector;
2537         if (_floppy->track && TRACK >= _floppy->track) {
2538                 if (blk_rq_cur_sectors(current_req) & 1) {
2539                         current_count_sectors = 1;
2540                         return 1;
2541                 } else
2542                         return 0;
2543         }
2544         HEAD = fsector_t / _floppy->sect;
2545
2546         if (((_floppy->stretch & (FD_SWAPSIDES | FD_SECTBASEMASK)) ||
2547              test_bit(FD_NEED_TWADDLE_BIT, &DRS->flags)) &&
2548             fsector_t < _floppy->sect)
2549                 max_sector = _floppy->sect;
2550
2551         /* 2M disks have phantom sectors on the first track */
2552         if ((_floppy->rate & FD_2M) && (!TRACK) && (!HEAD)) {
2553                 max_sector = 2 * _floppy->sect / 3;
2554                 if (fsector_t >= max_sector) {
2555                         current_count_sectors =
2556                             min_t(int, _floppy->sect - fsector_t,
2557                                   blk_rq_sectors(current_req));
2558                         return 1;
2559                 }
2560                 SIZECODE = 2;
2561         } else
2562                 SIZECODE = FD_SIZECODE(_floppy);
2563         raw_cmd->rate = _floppy->rate & 0x43;
2564         if ((_floppy->rate & FD_2M) && (TRACK || HEAD) && raw_cmd->rate == 2)
2565                 raw_cmd->rate = 1;
2566
2567         if (SIZECODE)
2568                 SIZECODE2 = 0xff;
2569         else
2570                 SIZECODE2 = 0x80;
2571         raw_cmd->track = TRACK << STRETCH(_floppy);
2572         DR_SELECT = UNIT(current_drive) + PH_HEAD(_floppy, HEAD);
2573         GAP = _floppy->gap;
2574         ssize = DIV_ROUND_UP(1 << SIZECODE, 4);
2575         SECT_PER_TRACK = _floppy->sect << 2 >> SIZECODE;
2576         SECTOR = ((fsector_t % _floppy->sect) << 2 >> SIZECODE) +
2577             FD_SECTBASE(_floppy);
2578
2579         /* tracksize describes the size which can be filled up with sectors
2580          * of size ssize.
2581          */
2582         tracksize = _floppy->sect - _floppy->sect % ssize;
2583         if (tracksize < _floppy->sect) {
2584                 SECT_PER_TRACK++;
2585                 if (tracksize <= fsector_t % _floppy->sect)
2586                         SECTOR--;
2587
2588                 /* if we are beyond tracksize, fill up using smaller sectors */
2589                 while (tracksize <= fsector_t % _floppy->sect) {
2590                         while (tracksize + ssize > _floppy->sect) {
2591                                 SIZECODE--;
2592                                 ssize >>= 1;
2593                         }
2594                         SECTOR++;
2595                         SECT_PER_TRACK++;
2596                         tracksize += ssize;
2597                 }
2598                 max_sector = HEAD * _floppy->sect + tracksize;
2599         } else if (!TRACK && !HEAD && !(_floppy->rate & FD_2M) && probing) {
2600                 max_sector = _floppy->sect;
2601         } else if (!HEAD && CT(COMMAND) == FD_WRITE) {
2602                 /* for virtual DMA bug workaround */
2603                 max_sector = _floppy->sect;
2604         }
2605
2606         in_sector_offset = (fsector_t % _floppy->sect) % ssize;
2607         aligned_sector_t = fsector_t - in_sector_offset;
2608         max_size = blk_rq_sectors(current_req);
2609         if ((raw_cmd->track == buffer_track) &&
2610             (current_drive == buffer_drive) &&
2611             (fsector_t >= buffer_min) && (fsector_t < buffer_max)) {
2612                 /* data already in track buffer */
2613                 if (CT(COMMAND) == FD_READ) {
2614                         copy_buffer(1, max_sector, buffer_max);
2615                         return 1;
2616                 }
2617         } else if (in_sector_offset || blk_rq_sectors(current_req) < ssize) {
2618                 if (CT(COMMAND) == FD_WRITE) {
2619                         unsigned int sectors;
2620
2621                         sectors = fsector_t + blk_rq_sectors(current_req);
2622                         if (sectors > ssize && sectors < ssize + ssize)
2623                                 max_size = ssize + ssize;
2624                         else
2625                                 max_size = ssize;
2626                 }
2627                 raw_cmd->flags &= ~FD_RAW_WRITE;
2628                 raw_cmd->flags |= FD_RAW_READ;
2629                 COMMAND = FM_MODE(_floppy, FD_READ);
2630         } else if ((unsigned long)current_req->buffer < MAX_DMA_ADDRESS) {
2631                 unsigned long dma_limit;
2632                 int direct, indirect;
2633
2634                 indirect =
2635                     transfer_size(ssize, max_sector,
2636                                   max_buffer_sectors * 2) - fsector_t;
2637
2638                 /*
2639                  * Do NOT use minimum() here---MAX_DMA_ADDRESS is 64 bits wide
2640                  * on a 64 bit machine!
2641                  */
2642                 max_size = buffer_chain_size();
2643                 dma_limit = (MAX_DMA_ADDRESS -
2644                              ((unsigned long)current_req->buffer)) >> 9;
2645                 if ((unsigned long)max_size > dma_limit)
2646                         max_size = dma_limit;
2647                 /* 64 kb boundaries */
2648                 if (CROSS_64KB(current_req->buffer, max_size << 9))
2649                         max_size = (K_64 -
2650                                     ((unsigned long)current_req->buffer) %
2651                                     K_64) >> 9;
2652                 direct = transfer_size(ssize, max_sector, max_size) - fsector_t;
2653                 /*
2654                  * We try to read tracks, but if we get too many errors, we
2655                  * go back to reading just one sector at a time.
2656                  *
2657                  * This means we should be able to read a sector even if there
2658                  * are other bad sectors on this track.
2659                  */
2660                 if (!direct ||
2661                     (indirect * 2 > direct * 3 &&
2662                      *errors < DP->max_errors.read_track &&
2663                      ((!probing ||
2664                        (DP->read_track & (1 << DRS->probed_format)))))) {
2665                         max_size = blk_rq_sectors(current_req);
2666                 } else {
2667                         raw_cmd->kernel_data = current_req->buffer;
2668                         raw_cmd->length = current_count_sectors << 9;
2669                         if (raw_cmd->length == 0) {
2670                                 DPRINT("%s: zero dma transfer attempted\n", __func__);
2671                                 DPRINT("indirect=%d direct=%d fsector_t=%d\n",
2672                                        indirect, direct, fsector_t);
2673                                 return 0;
2674                         }
2675                         virtualdmabug_workaround();
2676                         return 2;
2677                 }
2678         }
2679
2680         if (CT(COMMAND) == FD_READ)
2681                 max_size = max_sector;  /* unbounded */
2682
2683         /* claim buffer track if needed */
2684         if (buffer_track != raw_cmd->track ||   /* bad track */
2685             buffer_drive != current_drive ||    /* bad drive */
2686             fsector_t > buffer_max ||
2687             fsector_t < buffer_min ||
2688             ((CT(COMMAND) == FD_READ ||
2689               (!in_sector_offset && blk_rq_sectors(current_req) >= ssize)) &&
2690              max_sector > 2 * max_buffer_sectors + buffer_min &&
2691              max_size + fsector_t > 2 * max_buffer_sectors + buffer_min)) {
2692                 /* not enough space */
2693                 buffer_track = -1;
2694                 buffer_drive = current_drive;
2695                 buffer_max = buffer_min = aligned_sector_t;
2696         }
2697         raw_cmd->kernel_data = floppy_track_buffer +
2698                 ((aligned_sector_t - buffer_min) << 9);
2699
2700         if (CT(COMMAND) == FD_WRITE) {
2701                 /* copy write buffer to track buffer.
2702                  * if we get here, we know that the write
2703                  * is either aligned or the data already in the buffer
2704                  * (buffer will be overwritten) */
2705                 if (in_sector_offset && buffer_track == -1)
2706                         DPRINT("internal error offset !=0 on write\n");
2707                 buffer_track = raw_cmd->track;
2708                 buffer_drive = current_drive;
2709                 copy_buffer(ssize, max_sector,
2710                             2 * max_buffer_sectors + buffer_min);
2711         } else
2712                 transfer_size(ssize, max_sector,
2713                               2 * max_buffer_sectors + buffer_min -
2714                               aligned_sector_t);
2715
2716         /* round up current_count_sectors to get dma xfer size */
2717         raw_cmd->length = in_sector_offset + current_count_sectors;
2718         raw_cmd->length = ((raw_cmd->length - 1) | (ssize - 1)) + 1;
2719         raw_cmd->length <<= 9;
2720         if ((raw_cmd->length < current_count_sectors << 9) ||
2721             (raw_cmd->kernel_data != current_req->buffer &&
2722              CT(COMMAND) == FD_WRITE &&
2723              (aligned_sector_t + (raw_cmd->length >> 9) > buffer_max ||
2724               aligned_sector_t < buffer_min)) ||
2725             raw_cmd->length % (128 << SIZECODE) ||
2726             raw_cmd->length <= 0 || current_count_sectors <= 0) {
2727                 DPRINT("fractionary current count b=%lx s=%lx\n",
2728                        raw_cmd->length, current_count_sectors);
2729                 if (raw_cmd->kernel_data != current_req->buffer)
2730                         pr_info("addr=%d, length=%ld\n",
2731                                 (int)((raw_cmd->kernel_data -
2732                                        floppy_track_buffer) >> 9),
2733                                 current_count_sectors);
2734                 pr_info("st=%d ast=%d mse=%d msi=%d\n",
2735                         fsector_t, aligned_sector_t, max_sector, max_size);
2736                 pr_info("ssize=%x SIZECODE=%d\n", ssize, SIZECODE);
2737                 pr_info("command=%x SECTOR=%d HEAD=%d, TRACK=%d\n",
2738                         COMMAND, SECTOR, HEAD, TRACK);
2739                 pr_info("buffer drive=%d\n", buffer_drive);
2740                 pr_info("buffer track=%d\n", buffer_track);
2741                 pr_info("buffer_min=%d\n", buffer_min);
2742                 pr_info("buffer_max=%d\n", buffer_max);
2743                 return 0;
2744         }
2745
2746         if (raw_cmd->kernel_data != current_req->buffer) {
2747                 if (raw_cmd->kernel_data < floppy_track_buffer ||
2748                     current_count_sectors < 0 ||
2749                     raw_cmd->length < 0 ||
2750                     raw_cmd->kernel_data + raw_cmd->length >
2751                     floppy_track_buffer + (max_buffer_sectors << 10)) {
2752                         DPRINT("buffer overrun in schedule dma\n");
2753                         pr_info("fsector_t=%d buffer_min=%d current_count=%ld\n",
2754                                 fsector_t, buffer_min, raw_cmd->length >> 9);
2755                         pr_info("current_count_sectors=%ld\n",
2756                                 current_count_sectors);
2757                         if (CT(COMMAND) == FD_READ)
2758                                 pr_info("read\n");
2759                         if (CT(COMMAND) == FD_WRITE)
2760                                 pr_info("write\n");
2761                         return 0;
2762                 }
2763         } else if (raw_cmd->length > blk_rq_bytes(current_req) ||
2764                    current_count_sectors > blk_rq_sectors(current_req)) {
2765                 DPRINT("buffer overrun in direct transfer\n");
2766                 return 0;
2767         } else if (raw_cmd->length < current_count_sectors << 9) {
2768                 DPRINT("more sectors than bytes\n");
2769                 pr_info("bytes=%ld\n", raw_cmd->length >> 9);
2770                 pr_info("sectors=%ld\n", current_count_sectors);
2771         }
2772         if (raw_cmd->length == 0) {
2773                 DPRINT("zero dma transfer attempted from make_raw_request\n");
2774                 return 0;
2775         }
2776
2777         virtualdmabug_workaround();
2778         return 2;
2779 }
2780
2781 /*
2782  * Round-robin between our available drives, doing one request from each
2783  */
2784 static int set_next_request(void)
2785 {
2786         struct request_queue *q;
2787         int old_pos = fdc_queue;
2788
2789         do {