ia64/linux-2.6.18-xen.hg

view drivers/ide/ide-io.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /*
2 * IDE I/O functions
3 *
4 * Basic PIO and command management functionality.
5 *
6 * This code was split off from ide.c. See ide.c for history and original
7 * copyrights.
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2, or (at your option) any
12 * later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * For the avoidance of doubt the "preferred form" of this code is one which
20 * is in an open non patent encumbered format. Where cryptographic key signing
21 * forms part of the process of creating an executable the information
22 * including keys needed to generate an equivalently functional executable
23 * are deemed to be part of the source code.
24 */
27 #include <linux/module.h>
28 #include <linux/types.h>
29 #include <linux/string.h>
30 #include <linux/kernel.h>
31 #include <linux/timer.h>
32 #include <linux/mm.h>
33 #include <linux/interrupt.h>
34 #include <linux/major.h>
35 #include <linux/errno.h>
36 #include <linux/genhd.h>
37 #include <linux/blkpg.h>
38 #include <linux/slab.h>
39 #include <linux/init.h>
40 #include <linux/pci.h>
41 #include <linux/delay.h>
42 #include <linux/ide.h>
43 #include <linux/completion.h>
44 #include <linux/reboot.h>
45 #include <linux/cdrom.h>
46 #include <linux/seq_file.h>
47 #include <linux/device.h>
48 #include <linux/kmod.h>
49 #include <linux/scatterlist.h>
51 #include <asm/byteorder.h>
52 #include <asm/irq.h>
53 #include <asm/uaccess.h>
54 #include <asm/io.h>
55 #include <asm/bitops.h>
57 static int __ide_end_request(ide_drive_t *drive, struct request *rq,
58 int uptodate, int nr_sectors)
59 {
60 int ret = 1;
62 BUG_ON(!(rq->flags & REQ_STARTED));
64 /*
65 * if failfast is set on a request, override number of sectors and
66 * complete the whole request right now
67 */
68 if (blk_noretry_request(rq) && end_io_error(uptodate))
69 nr_sectors = rq->hard_nr_sectors;
71 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
72 rq->errors = -EIO;
74 /*
75 * decide whether to reenable DMA -- 3 is a random magic for now,
76 * if we DMA timeout more than 3 times, just stay in PIO
77 */
78 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
79 drive->state = 0;
80 HWGROUP(drive)->hwif->ide_dma_on(drive);
81 }
83 if (!end_that_request_first(rq, uptodate, nr_sectors)) {
84 add_disk_randomness(rq->rq_disk);
85 blkdev_dequeue_request(rq);
86 HWGROUP(drive)->rq = NULL;
87 end_that_request_last(rq, uptodate);
88 ret = 0;
89 }
91 return ret;
92 }
94 /**
95 * ide_end_request - complete an IDE I/O
96 * @drive: IDE device for the I/O
97 * @uptodate:
98 * @nr_sectors: number of sectors completed
99 *
100 * This is our end_request wrapper function. We complete the I/O
101 * update random number input and dequeue the request, which if
102 * it was tagged may be out of order.
103 */
105 int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
106 {
107 struct request *rq;
108 unsigned long flags;
109 int ret = 1;
111 /*
112 * room for locking improvements here, the calls below don't
113 * need the queue lock held at all
114 */
115 spin_lock_irqsave(&ide_lock, flags);
116 rq = HWGROUP(drive)->rq;
118 if (!nr_sectors)
119 nr_sectors = rq->hard_cur_sectors;
121 ret = __ide_end_request(drive, rq, uptodate, nr_sectors);
123 spin_unlock_irqrestore(&ide_lock, flags);
124 return ret;
125 }
126 EXPORT_SYMBOL(ide_end_request);
128 /*
129 * Power Management state machine. This one is rather trivial for now,
130 * we should probably add more, like switching back to PIO on suspend
131 * to help some BIOSes, re-do the door locking on resume, etc...
132 */
134 enum {
135 ide_pm_flush_cache = ide_pm_state_start_suspend,
136 idedisk_pm_standby,
138 idedisk_pm_idle = ide_pm_state_start_resume,
139 ide_pm_restore_dma,
140 };
142 static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error)
143 {
144 struct request_pm_state *pm = rq->end_io_data;
146 if (drive->media != ide_disk)
147 return;
149 switch (pm->pm_step) {
150 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */
151 if (pm->pm_state == PM_EVENT_FREEZE)
152 pm->pm_step = ide_pm_state_completed;
153 else
154 pm->pm_step = idedisk_pm_standby;
155 break;
156 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */
157 pm->pm_step = ide_pm_state_completed;
158 break;
159 case idedisk_pm_idle: /* Resume step 1 (idle) complete */
160 pm->pm_step = ide_pm_restore_dma;
161 break;
162 }
163 }
165 static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq)
166 {
167 struct request_pm_state *pm = rq->end_io_data;
168 ide_task_t *args = rq->special;
170 memset(args, 0, sizeof(*args));
172 if (drive->media != ide_disk) {
173 /* skip idedisk_pm_idle for ATAPI devices */
174 if (pm->pm_step == idedisk_pm_idle)
175 pm->pm_step = ide_pm_restore_dma;
176 }
178 switch (pm->pm_step) {
179 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */
180 if (drive->media != ide_disk)
181 break;
182 /* Not supported? Switch to next step now. */
183 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) {
184 ide_complete_power_step(drive, rq, 0, 0);
185 return ide_stopped;
186 }
187 if (ide_id_has_flush_cache_ext(drive->id))
188 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE_EXT;
189 else
190 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE;
191 args->command_type = IDE_DRIVE_TASK_NO_DATA;
192 args->handler = &task_no_data_intr;
193 return do_rw_taskfile(drive, args);
195 case idedisk_pm_standby: /* Suspend step 2 (standby) */
196 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_STANDBYNOW1;
197 args->command_type = IDE_DRIVE_TASK_NO_DATA;
198 args->handler = &task_no_data_intr;
199 return do_rw_taskfile(drive, args);
201 case idedisk_pm_idle: /* Resume step 1 (idle) */
202 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_IDLEIMMEDIATE;
203 args->command_type = IDE_DRIVE_TASK_NO_DATA;
204 args->handler = task_no_data_intr;
205 return do_rw_taskfile(drive, args);
207 case ide_pm_restore_dma: /* Resume step 2 (restore DMA) */
208 /*
209 * Right now, all we do is call hwif->ide_dma_check(drive),
210 * we could be smarter and check for current xfer_speed
211 * in struct drive etc...
212 */
213 if ((drive->id->capability & 1) == 0)
214 break;
215 if (drive->hwif->ide_dma_check == NULL)
216 break;
217 drive->hwif->ide_dma_check(drive);
218 break;
219 }
220 pm->pm_step = ide_pm_state_completed;
221 return ide_stopped;
222 }
224 /**
225 * ide_end_dequeued_request - complete an IDE I/O
226 * @drive: IDE device for the I/O
227 * @uptodate:
228 * @nr_sectors: number of sectors completed
229 *
230 * Complete an I/O that is no longer on the request queue. This
231 * typically occurs when we pull the request and issue a REQUEST_SENSE.
232 * We must still finish the old request but we must not tamper with the
233 * queue in the meantime.
234 *
235 * NOTE: This path does not handle barrier, but barrier is not supported
236 * on ide-cd anyway.
237 */
239 int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
240 int uptodate, int nr_sectors)
241 {
242 unsigned long flags;
243 int ret = 1;
245 spin_lock_irqsave(&ide_lock, flags);
247 BUG_ON(!(rq->flags & REQ_STARTED));
249 /*
250 * if failfast is set on a request, override number of sectors and
251 * complete the whole request right now
252 */
253 if (blk_noretry_request(rq) && end_io_error(uptodate))
254 nr_sectors = rq->hard_nr_sectors;
256 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
257 rq->errors = -EIO;
259 /*
260 * decide whether to reenable DMA -- 3 is a random magic for now,
261 * if we DMA timeout more than 3 times, just stay in PIO
262 */
263 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
264 drive->state = 0;
265 HWGROUP(drive)->hwif->ide_dma_on(drive);
266 }
268 if (!end_that_request_first(rq, uptodate, nr_sectors)) {
269 add_disk_randomness(rq->rq_disk);
270 if (blk_rq_tagged(rq))
271 blk_queue_end_tag(drive->queue, rq);
272 end_that_request_last(rq, uptodate);
273 ret = 0;
274 }
275 spin_unlock_irqrestore(&ide_lock, flags);
276 return ret;
277 }
278 EXPORT_SYMBOL_GPL(ide_end_dequeued_request);
281 /**
282 * ide_complete_pm_request - end the current Power Management request
283 * @drive: target drive
284 * @rq: request
285 *
286 * This function cleans up the current PM request and stops the queue
287 * if necessary.
288 */
289 static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
290 {
291 unsigned long flags;
293 #ifdef DEBUG_PM
294 printk("%s: completing PM request, %s\n", drive->name,
295 blk_pm_suspend_request(rq) ? "suspend" : "resume");
296 #endif
297 spin_lock_irqsave(&ide_lock, flags);
298 if (blk_pm_suspend_request(rq)) {
299 blk_stop_queue(drive->queue);
300 } else {
301 drive->blocked = 0;
302 blk_start_queue(drive->queue);
303 }
304 blkdev_dequeue_request(rq);
305 HWGROUP(drive)->rq = NULL;
306 end_that_request_last(rq, 1);
307 spin_unlock_irqrestore(&ide_lock, flags);
308 }
310 /*
311 * FIXME: probably move this somewhere else, name is bad too :)
312 */
313 u64 ide_get_error_location(ide_drive_t *drive, char *args)
314 {
315 u32 high, low;
316 u8 hcyl, lcyl, sect;
317 u64 sector;
319 high = 0;
320 hcyl = args[5];
321 lcyl = args[4];
322 sect = args[3];
324 if (ide_id_has_flush_cache_ext(drive->id)) {
325 low = (hcyl << 16) | (lcyl << 8) | sect;
326 HWIF(drive)->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
327 high = ide_read_24(drive);
328 } else {
329 u8 cur = HWIF(drive)->INB(IDE_SELECT_REG);
330 if (cur & 0x40) {
331 high = cur & 0xf;
332 low = (hcyl << 16) | (lcyl << 8) | sect;
333 } else {
334 low = hcyl * drive->head * drive->sect;
335 low += lcyl * drive->sect;
336 low += sect - 1;
337 }
338 }
340 sector = ((u64) high << 24) | low;
341 return sector;
342 }
343 EXPORT_SYMBOL(ide_get_error_location);
345 /**
346 * ide_end_drive_cmd - end an explicit drive command
347 * @drive: command
348 * @stat: status bits
349 * @err: error bits
350 *
351 * Clean up after success/failure of an explicit drive command.
352 * These get thrown onto the queue so they are synchronized with
353 * real I/O operations on the drive.
354 *
355 * In LBA48 mode we have to read the register set twice to get
356 * all the extra information out.
357 */
359 void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
360 {
361 ide_hwif_t *hwif = HWIF(drive);
362 unsigned long flags;
363 struct request *rq;
365 spin_lock_irqsave(&ide_lock, flags);
366 rq = HWGROUP(drive)->rq;
367 spin_unlock_irqrestore(&ide_lock, flags);
369 if (rq->flags & REQ_DRIVE_CMD) {
370 u8 *args = (u8 *) rq->buffer;
371 if (rq->errors == 0)
372 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
374 if (args) {
375 args[0] = stat;
376 args[1] = err;
377 args[2] = hwif->INB(IDE_NSECTOR_REG);
378 }
379 } else if (rq->flags & REQ_DRIVE_TASK) {
380 u8 *args = (u8 *) rq->buffer;
381 if (rq->errors == 0)
382 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
384 if (args) {
385 args[0] = stat;
386 args[1] = err;
387 args[2] = hwif->INB(IDE_NSECTOR_REG);
388 args[3] = hwif->INB(IDE_SECTOR_REG);
389 args[4] = hwif->INB(IDE_LCYL_REG);
390 args[5] = hwif->INB(IDE_HCYL_REG);
391 args[6] = hwif->INB(IDE_SELECT_REG);
392 }
393 } else if (rq->flags & REQ_DRIVE_TASKFILE) {
394 ide_task_t *args = (ide_task_t *) rq->special;
395 if (rq->errors == 0)
396 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
398 if (args) {
399 if (args->tf_in_flags.b.data) {
400 u16 data = hwif->INW(IDE_DATA_REG);
401 args->tfRegister[IDE_DATA_OFFSET] = (data) & 0xFF;
402 args->hobRegister[IDE_DATA_OFFSET] = (data >> 8) & 0xFF;
403 }
404 args->tfRegister[IDE_ERROR_OFFSET] = err;
405 /* be sure we're looking at the low order bits */
406 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG);
407 args->tfRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
408 args->tfRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
409 args->tfRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
410 args->tfRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
411 args->tfRegister[IDE_SELECT_OFFSET] = hwif->INB(IDE_SELECT_REG);
412 args->tfRegister[IDE_STATUS_OFFSET] = stat;
414 if (drive->addressing == 1) {
415 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
416 args->hobRegister[IDE_FEATURE_OFFSET] = hwif->INB(IDE_FEATURE_REG);
417 args->hobRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
418 args->hobRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
419 args->hobRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
420 args->hobRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
421 }
422 }
423 } else if (blk_pm_request(rq)) {
424 struct request_pm_state *pm = rq->end_io_data;
425 #ifdef DEBUG_PM
426 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
427 drive->name, rq->pm->pm_step, stat, err);
428 #endif
429 ide_complete_power_step(drive, rq, stat, err);
430 if (pm->pm_step == ide_pm_state_completed)
431 ide_complete_pm_request(drive, rq);
432 return;
433 }
435 spin_lock_irqsave(&ide_lock, flags);
436 blkdev_dequeue_request(rq);
437 HWGROUP(drive)->rq = NULL;
438 rq->errors = err;
439 end_that_request_last(rq, !rq->errors);
440 spin_unlock_irqrestore(&ide_lock, flags);
441 }
443 EXPORT_SYMBOL(ide_end_drive_cmd);
445 /**
446 * try_to_flush_leftover_data - flush junk
447 * @drive: drive to flush
448 *
449 * try_to_flush_leftover_data() is invoked in response to a drive
450 * unexpectedly having its DRQ_STAT bit set. As an alternative to
451 * resetting the drive, this routine tries to clear the condition
452 * by read a sector's worth of data from the drive. Of course,
453 * this may not help if the drive is *waiting* for data from *us*.
454 */
455 static void try_to_flush_leftover_data (ide_drive_t *drive)
456 {
457 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;
459 if (drive->media != ide_disk)
460 return;
461 while (i > 0) {
462 u32 buffer[16];
463 u32 wcount = (i > 16) ? 16 : i;
465 i -= wcount;
466 HWIF(drive)->ata_input_data(drive, buffer, wcount);
467 }
468 }
470 static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
471 {
472 if (rq->rq_disk) {
473 ide_driver_t *drv;
475 drv = *(ide_driver_t **)rq->rq_disk->private_data;
476 drv->end_request(drive, 0, 0);
477 } else
478 ide_end_request(drive, 0, 0);
479 }
481 static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
482 {
483 ide_hwif_t *hwif = drive->hwif;
485 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
486 /* other bits are useless when BUSY */
487 rq->errors |= ERROR_RESET;
488 } else if (stat & ERR_STAT) {
489 /* err has different meaning on cdrom and tape */
490 if (err == ABRT_ERR) {
491 if (drive->select.b.lba &&
492 /* some newer drives don't support WIN_SPECIFY */
493 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
494 return ide_stopped;
495 } else if ((err & BAD_CRC) == BAD_CRC) {
496 /* UDMA crc error, just retry the operation */
497 drive->crc_count++;
498 } else if (err & (BBD_ERR | ECC_ERR)) {
499 /* retries won't help these */
500 rq->errors = ERROR_MAX;
501 } else if (err & TRK0_ERR) {
502 /* help it find track zero */
503 rq->errors |= ERROR_RECAL;
504 }
505 }
507 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ && hwif->err_stops_fifo == 0)
508 try_to_flush_leftover_data(drive);
510 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
511 /* force an abort */
512 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
514 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq))
515 ide_kill_rq(drive, rq);
516 else {
517 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
518 ++rq->errors;
519 return ide_do_reset(drive);
520 }
521 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
522 drive->special.b.recalibrate = 1;
523 ++rq->errors;
524 }
525 return ide_stopped;
526 }
528 static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
529 {
530 ide_hwif_t *hwif = drive->hwif;
532 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
533 /* other bits are useless when BUSY */
534 rq->errors |= ERROR_RESET;
535 } else {
536 /* add decoding error stuff */
537 }
539 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
540 /* force an abort */
541 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
543 if (rq->errors >= ERROR_MAX) {
544 ide_kill_rq(drive, rq);
545 } else {
546 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
547 ++rq->errors;
548 return ide_do_reset(drive);
549 }
550 ++rq->errors;
551 }
553 return ide_stopped;
554 }
556 ide_startstop_t
557 __ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
558 {
559 if (drive->media == ide_disk)
560 return ide_ata_error(drive, rq, stat, err);
561 return ide_atapi_error(drive, rq, stat, err);
562 }
564 EXPORT_SYMBOL_GPL(__ide_error);
566 /**
567 * ide_error - handle an error on the IDE
568 * @drive: drive the error occurred on
569 * @msg: message to report
570 * @stat: status bits
571 *
572 * ide_error() takes action based on the error returned by the drive.
573 * For normal I/O that may well include retries. We deal with
574 * both new-style (taskfile) and old style command handling here.
575 * In the case of taskfile command handling there is work left to
576 * do
577 */
579 ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
580 {
581 struct request *rq;
582 u8 err;
584 err = ide_dump_status(drive, msg, stat);
586 if ((rq = HWGROUP(drive)->rq) == NULL)
587 return ide_stopped;
589 /* retry only "normal" I/O: */
590 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) {
591 rq->errors = 1;
592 ide_end_drive_cmd(drive, stat, err);
593 return ide_stopped;
594 }
596 if (rq->rq_disk) {
597 ide_driver_t *drv;
599 drv = *(ide_driver_t **)rq->rq_disk->private_data;
600 return drv->error(drive, rq, stat, err);
601 } else
602 return __ide_error(drive, rq, stat, err);
603 }
605 EXPORT_SYMBOL_GPL(ide_error);
607 ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
608 {
609 if (drive->media != ide_disk)
610 rq->errors |= ERROR_RESET;
612 ide_kill_rq(drive, rq);
614 return ide_stopped;
615 }
617 EXPORT_SYMBOL_GPL(__ide_abort);
619 /**
620 * ide_abort - abort pending IDE operations
621 * @drive: drive the error occurred on
622 * @msg: message to report
623 *
624 * ide_abort kills and cleans up when we are about to do a
625 * host initiated reset on active commands. Longer term we
626 * want handlers to have sensible abort handling themselves
627 *
628 * This differs fundamentally from ide_error because in
629 * this case the command is doing just fine when we
630 * blow it away.
631 */
633 ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
634 {
635 struct request *rq;
637 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
638 return ide_stopped;
640 /* retry only "normal" I/O: */
641 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) {
642 rq->errors = 1;
643 ide_end_drive_cmd(drive, BUSY_STAT, 0);
644 return ide_stopped;
645 }
647 if (rq->rq_disk) {
648 ide_driver_t *drv;
650 drv = *(ide_driver_t **)rq->rq_disk->private_data;
651 return drv->abort(drive, rq);
652 } else
653 return __ide_abort(drive, rq);
654 }
656 /**
657 * ide_cmd - issue a simple drive command
658 * @drive: drive the command is for
659 * @cmd: command byte
660 * @nsect: sector byte
661 * @handler: handler for the command completion
662 *
663 * Issue a simple drive command with interrupts.
664 * The drive must be selected beforehand.
665 */
667 static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect,
668 ide_handler_t *handler)
669 {
670 ide_hwif_t *hwif = HWIF(drive);
671 if (IDE_CONTROL_REG)
672 hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */
673 SELECT_MASK(drive,0);
674 hwif->OUTB(nsect,IDE_NSECTOR_REG);
675 ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL);
676 }
678 /**
679 * drive_cmd_intr - drive command completion interrupt
680 * @drive: drive the completion interrupt occurred on
681 *
682 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
683 * We do any necessary data reading and then wait for the drive to
684 * go non busy. At that point we may read the error data and complete
685 * the request
686 */
688 static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
689 {
690 struct request *rq = HWGROUP(drive)->rq;
691 ide_hwif_t *hwif = HWIF(drive);
692 u8 *args = (u8 *) rq->buffer;
693 u8 stat = hwif->INB(IDE_STATUS_REG);
694 int retries = 10;
696 local_irq_enable_in_hardirq();
697 if ((stat & DRQ_STAT) && args && args[3]) {
698 u8 io_32bit = drive->io_32bit;
699 drive->io_32bit = 0;
700 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
701 drive->io_32bit = io_32bit;
702 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
703 udelay(100);
704 }
706 if (!OK_STAT(stat, READY_STAT, BAD_STAT))
707 return ide_error(drive, "drive_cmd", stat);
708 /* calls ide_end_drive_cmd */
709 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
710 return ide_stopped;
711 }
713 static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task)
714 {
715 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
716 task->tfRegister[IDE_SECTOR_OFFSET] = drive->sect;
717 task->tfRegister[IDE_LCYL_OFFSET] = drive->cyl;
718 task->tfRegister[IDE_HCYL_OFFSET] = drive->cyl>>8;
719 task->tfRegister[IDE_SELECT_OFFSET] = ((drive->head-1)|drive->select.all)&0xBF;
720 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY;
722 task->handler = &set_geometry_intr;
723 }
725 static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task)
726 {
727 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
728 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE;
730 task->handler = &recal_intr;
731 }
733 static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task)
734 {
735 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req;
736 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT;
738 task->handler = &set_multmode_intr;
739 }
741 static ide_startstop_t ide_disk_special(ide_drive_t *drive)
742 {
743 special_t *s = &drive->special;
744 ide_task_t args;
746 memset(&args, 0, sizeof(ide_task_t));
747 args.command_type = IDE_DRIVE_TASK_NO_DATA;
749 if (s->b.set_geometry) {
750 s->b.set_geometry = 0;
751 ide_init_specify_cmd(drive, &args);
752 } else if (s->b.recalibrate) {
753 s->b.recalibrate = 0;
754 ide_init_restore_cmd(drive, &args);
755 } else if (s->b.set_multmode) {
756 s->b.set_multmode = 0;
757 if (drive->mult_req > drive->id->max_multsect)
758 drive->mult_req = drive->id->max_multsect;
759 ide_init_setmult_cmd(drive, &args);
760 } else if (s->all) {
761 int special = s->all;
762 s->all = 0;
763 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
764 return ide_stopped;
765 }
767 do_rw_taskfile(drive, &args);
769 return ide_started;
770 }
772 /**
773 * do_special - issue some special commands
774 * @drive: drive the command is for
775 *
776 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
777 * commands to a drive. It used to do much more, but has been scaled
778 * back.
779 */
781 static ide_startstop_t do_special (ide_drive_t *drive)
782 {
783 special_t *s = &drive->special;
785 #ifdef DEBUG
786 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
787 #endif
788 if (s->b.set_tune) {
789 s->b.set_tune = 0;
790 if (HWIF(drive)->tuneproc != NULL)
791 HWIF(drive)->tuneproc(drive, drive->tune_req);
792 return ide_stopped;
793 } else {
794 if (drive->media == ide_disk)
795 return ide_disk_special(drive);
797 s->all = 0;
798 drive->mult_req = 0;
799 return ide_stopped;
800 }
801 }
803 void ide_map_sg(ide_drive_t *drive, struct request *rq)
804 {
805 ide_hwif_t *hwif = drive->hwif;
806 struct scatterlist *sg = hwif->sg_table;
808 if (hwif->sg_mapped) /* needed by ide-scsi */
809 return;
811 if ((rq->flags & REQ_DRIVE_TASKFILE) == 0) {
812 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
813 } else {
814 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
815 hwif->sg_nents = 1;
816 }
817 }
819 EXPORT_SYMBOL_GPL(ide_map_sg);
821 void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
822 {
823 ide_hwif_t *hwif = drive->hwif;
825 hwif->nsect = hwif->nleft = rq->nr_sectors;
826 hwif->cursg = hwif->cursg_ofs = 0;
827 }
829 EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
831 /**
832 * execute_drive_command - issue special drive command
833 * @drive: the drive to issue the command on
834 * @rq: the request structure holding the command
835 *
836 * execute_drive_cmd() issues a special drive command, usually
837 * initiated by ioctl() from the external hdparm program. The
838 * command can be a drive command, drive task or taskfile
839 * operation. Weirdly you can call it with NULL to wait for
840 * all commands to finish. Don't do this as that is due to change
841 */
843 static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
844 struct request *rq)
845 {
846 ide_hwif_t *hwif = HWIF(drive);
847 if (rq->flags & REQ_DRIVE_TASKFILE) {
848 ide_task_t *args = rq->special;
850 if (!args)
851 goto done;
853 hwif->data_phase = args->data_phase;
855 switch (hwif->data_phase) {
856 case TASKFILE_MULTI_OUT:
857 case TASKFILE_OUT:
858 case TASKFILE_MULTI_IN:
859 case TASKFILE_IN:
860 ide_init_sg_cmd(drive, rq);
861 ide_map_sg(drive, rq);
862 default:
863 break;
864 }
866 if (args->tf_out_flags.all != 0)
867 return flagged_taskfile(drive, args);
868 return do_rw_taskfile(drive, args);
869 } else if (rq->flags & REQ_DRIVE_TASK) {
870 u8 *args = rq->buffer;
871 u8 sel;
873 if (!args)
874 goto done;
875 #ifdef DEBUG
876 printk("%s: DRIVE_TASK_CMD ", drive->name);
877 printk("cmd=0x%02x ", args[0]);
878 printk("fr=0x%02x ", args[1]);
879 printk("ns=0x%02x ", args[2]);
880 printk("sc=0x%02x ", args[3]);
881 printk("lcyl=0x%02x ", args[4]);
882 printk("hcyl=0x%02x ", args[5]);
883 printk("sel=0x%02x\n", args[6]);
884 #endif
885 hwif->OUTB(args[1], IDE_FEATURE_REG);
886 hwif->OUTB(args[3], IDE_SECTOR_REG);
887 hwif->OUTB(args[4], IDE_LCYL_REG);
888 hwif->OUTB(args[5], IDE_HCYL_REG);
889 sel = (args[6] & ~0x10);
890 if (drive->select.b.unit)
891 sel |= 0x10;
892 hwif->OUTB(sel, IDE_SELECT_REG);
893 ide_cmd(drive, args[0], args[2], &drive_cmd_intr);
894 return ide_started;
895 } else if (rq->flags & REQ_DRIVE_CMD) {
896 u8 *args = rq->buffer;
898 if (!args)
899 goto done;
900 #ifdef DEBUG
901 printk("%s: DRIVE_CMD ", drive->name);
902 printk("cmd=0x%02x ", args[0]);
903 printk("sc=0x%02x ", args[1]);
904 printk("fr=0x%02x ", args[2]);
905 printk("xx=0x%02x\n", args[3]);
906 #endif
907 if (args[0] == WIN_SMART) {
908 hwif->OUTB(0x4f, IDE_LCYL_REG);
909 hwif->OUTB(0xc2, IDE_HCYL_REG);
910 hwif->OUTB(args[2],IDE_FEATURE_REG);
911 hwif->OUTB(args[1],IDE_SECTOR_REG);
912 ide_cmd(drive, args[0], args[3], &drive_cmd_intr);
913 return ide_started;
914 }
915 hwif->OUTB(args[2],IDE_FEATURE_REG);
916 ide_cmd(drive, args[0], args[1], &drive_cmd_intr);
917 return ide_started;
918 }
920 done:
921 /*
922 * NULL is actually a valid way of waiting for
923 * all current requests to be flushed from the queue.
924 */
925 #ifdef DEBUG
926 printk("%s: DRIVE_CMD (null)\n", drive->name);
927 #endif
928 ide_end_drive_cmd(drive,
929 hwif->INB(IDE_STATUS_REG),
930 hwif->INB(IDE_ERROR_REG));
931 return ide_stopped;
932 }
934 static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
935 {
936 struct request_pm_state *pm = rq->end_io_data;
938 if (blk_pm_suspend_request(rq) &&
939 pm->pm_step == ide_pm_state_start_suspend)
940 /* Mark drive blocked when starting the suspend sequence. */
941 drive->blocked = 1;
942 else if (blk_pm_resume_request(rq) &&
943 pm->pm_step == ide_pm_state_start_resume) {
944 /*
945 * The first thing we do on wakeup is to wait for BSY bit to
946 * go away (with a looong timeout) as a drive on this hwif may
947 * just be POSTing itself.
948 * We do that before even selecting as the "other" device on
949 * the bus may be broken enough to walk on our toes at this
950 * point.
951 */
952 int rc;
953 #ifdef DEBUG_PM
954 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
955 #endif
956 rc = ide_wait_not_busy(HWIF(drive), 35000);
957 if (rc)
958 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
959 SELECT_DRIVE(drive);
960 HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]);
961 rc = ide_wait_not_busy(HWIF(drive), 100000);
962 if (rc)
963 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
964 }
965 }
967 /**
968 * start_request - start of I/O and command issuing for IDE
969 *
970 * start_request() initiates handling of a new I/O request. It
971 * accepts commands and I/O (read/write) requests. It also does
972 * the final remapping for weird stuff like EZDrive. Once
973 * device mapper can work sector level the EZDrive stuff can go away
974 *
975 * FIXME: this function needs a rename
976 */
978 static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
979 {
980 ide_startstop_t startstop;
981 sector_t block;
983 BUG_ON(!(rq->flags & REQ_STARTED));
985 #ifdef DEBUG
986 printk("%s: start_request: current=0x%08lx\n",
987 HWIF(drive)->name, (unsigned long) rq);
988 #endif
990 /* bail early if we've exceeded max_failures */
991 if (drive->max_failures && (drive->failures > drive->max_failures)) {
992 goto kill_rq;
993 }
995 block = rq->sector;
996 if (blk_fs_request(rq) &&
997 (drive->media == ide_disk || drive->media == ide_floppy)) {
998 block += drive->sect0;
999 }
1000 /* Yecch - this will shift the entire interval,
1001 possibly killing some innocent following sector */
1002 if (block == 0 && drive->remap_0_to_1 == 1)
1003 block = 1; /* redirect MBR access to EZ-Drive partn table */
1005 if (blk_pm_request(rq))
1006 ide_check_pm_state(drive, rq);
1008 SELECT_DRIVE(drive);
1009 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
1010 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
1011 return startstop;
1013 if (!drive->special.all) {
1014 ide_driver_t *drv;
1016 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK))
1017 return execute_drive_cmd(drive, rq);
1018 else if (rq->flags & REQ_DRIVE_TASKFILE)
1019 return execute_drive_cmd(drive, rq);
1020 else if (blk_pm_request(rq)) {
1021 struct request_pm_state *pm = rq->end_io_data;
1022 #ifdef DEBUG_PM
1023 printk("%s: start_power_step(step: %d)\n",
1024 drive->name, rq->pm->pm_step);
1025 #endif
1026 startstop = ide_start_power_step(drive, rq);
1027 if (startstop == ide_stopped &&
1028 pm->pm_step == ide_pm_state_completed)
1029 ide_complete_pm_request(drive, rq);
1030 return startstop;
1033 drv = *(ide_driver_t **)rq->rq_disk->private_data;
1034 return drv->do_request(drive, rq, block);
1036 return do_special(drive);
1037 kill_rq:
1038 ide_kill_rq(drive, rq);
1039 return ide_stopped;
1042 /**
1043 * ide_stall_queue - pause an IDE device
1044 * @drive: drive to stall
1045 * @timeout: time to stall for (jiffies)
1047 * ide_stall_queue() can be used by a drive to give excess bandwidth back
1048 * to the hwgroup by sleeping for timeout jiffies.
1049 */
1051 void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
1053 if (timeout > WAIT_WORSTCASE)
1054 timeout = WAIT_WORSTCASE;
1055 drive->sleep = timeout + jiffies;
1056 drive->sleeping = 1;
1059 EXPORT_SYMBOL(ide_stall_queue);
1061 #define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
1063 /**
1064 * choose_drive - select a drive to service
1065 * @hwgroup: hardware group to select on
1067 * choose_drive() selects the next drive which will be serviced.
1068 * This is necessary because the IDE layer can't issue commands
1069 * to both drives on the same cable, unlike SCSI.
1070 */
1072 static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
1074 ide_drive_t *drive, *best;
1076 repeat:
1077 best = NULL;
1078 drive = hwgroup->drive;
1080 /*
1081 * drive is doing pre-flush, ordered write, post-flush sequence. even
1082 * though that is 3 requests, it must be seen as a single transaction.
1083 * we must not preempt this drive until that is complete
1084 */
1085 if (blk_queue_flushing(drive->queue)) {
1086 /*
1087 * small race where queue could get replugged during
1088 * the 3-request flush cycle, just yank the plug since
1089 * we want it to finish asap
1090 */
1091 blk_remove_plug(drive->queue);
1092 return drive;
1095 do {
1096 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
1097 && !elv_queue_empty(drive->queue)) {
1098 if (!best
1099 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
1100 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
1102 if (!blk_queue_plugged(drive->queue))
1103 best = drive;
1106 } while ((drive = drive->next) != hwgroup->drive);
1107 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1108 long t = (signed long)(WAKEUP(best) - jiffies);
1109 if (t >= WAIT_MIN_SLEEP) {
1110 /*
1111 * We *may* have some time to spare, but first let's see if
1112 * someone can potentially benefit from our nice mood today..
1113 */
1114 drive = best->next;
1115 do {
1116 if (!drive->sleeping
1117 && time_before(jiffies - best->service_time, WAKEUP(drive))
1118 && time_before(WAKEUP(drive), jiffies + t))
1120 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1121 goto repeat;
1123 } while ((drive = drive->next) != best);
1126 return best;
1129 /*
1130 * Issue a new request to a drive from hwgroup
1131 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1133 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1134 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1135 * may have both interfaces in a single hwgroup to "serialize" access.
1136 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1137 * together into one hwgroup for serialized access.
1139 * Note also that several hwgroups can end up sharing a single IRQ,
1140 * possibly along with many other devices. This is especially common in
1141 * PCI-based systems with off-board IDE controller cards.
1143 * The IDE driver uses the single global ide_lock spinlock to protect
1144 * access to the request queues, and to protect the hwgroup->busy flag.
1146 * The first thread into the driver for a particular hwgroup sets the
1147 * hwgroup->busy flag to indicate that this hwgroup is now active,
1148 * and then initiates processing of the top request from the request queue.
1150 * Other threads attempting entry notice the busy setting, and will simply
1151 * queue their new requests and exit immediately. Note that hwgroup->busy
1152 * remains set even when the driver is merely awaiting the next interrupt.
1153 * Thus, the meaning is "this hwgroup is busy processing a request".
1155 * When processing of a request completes, the completing thread or IRQ-handler
1156 * will start the next request from the queue. If no more work remains,
1157 * the driver will clear the hwgroup->busy flag and exit.
1159 * The ide_lock (spinlock) is used to protect all access to the
1160 * hwgroup->busy flag, but is otherwise not needed for most processing in
1161 * the driver. This makes the driver much more friendlier to shared IRQs
1162 * than previous designs, while remaining 100% (?) SMP safe and capable.
1163 */
1164 static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1166 ide_drive_t *drive;
1167 ide_hwif_t *hwif;
1168 struct request *rq;
1169 ide_startstop_t startstop;
1170 int loops = 0;
1172 /* for atari only: POSSIBLY BROKEN HERE(?) */
1173 ide_get_lock(ide_intr, hwgroup);
1175 /* caller must own ide_lock */
1176 BUG_ON(!irqs_disabled());
1178 while (!hwgroup->busy) {
1179 hwgroup->busy = 1;
1180 drive = choose_drive(hwgroup);
1181 if (drive == NULL) {
1182 int sleeping = 0;
1183 unsigned long sleep = 0; /* shut up, gcc */
1184 hwgroup->rq = NULL;
1185 drive = hwgroup->drive;
1186 do {
1187 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1188 sleeping = 1;
1189 sleep = drive->sleep;
1191 } while ((drive = drive->next) != hwgroup->drive);
1192 if (sleeping) {
1193 /*
1194 * Take a short snooze, and then wake up this hwgroup again.
1195 * This gives other hwgroups on the same a chance to
1196 * play fairly with us, just in case there are big differences
1197 * in relative throughputs.. don't want to hog the cpu too much.
1198 */
1199 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1200 sleep = jiffies + WAIT_MIN_SLEEP;
1201 #if 1
1202 if (timer_pending(&hwgroup->timer))
1203 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1204 #endif
1205 /* so that ide_timer_expiry knows what to do */
1206 hwgroup->sleeping = 1;
1207 mod_timer(&hwgroup->timer, sleep);
1208 /* we purposely leave hwgroup->busy==1
1209 * while sleeping */
1210 } else {
1211 /* Ugly, but how can we sleep for the lock
1212 * otherwise? perhaps from tq_disk?
1213 */
1215 /* for atari only */
1216 ide_release_lock();
1217 hwgroup->busy = 0;
1220 /* no more work for this hwgroup (for now) */
1221 return;
1223 again:
1224 hwif = HWIF(drive);
1225 if (hwgroup->hwif->sharing_irq &&
1226 hwif != hwgroup->hwif &&
1227 hwif->io_ports[IDE_CONTROL_OFFSET]) {
1228 /* set nIEN for previous hwif */
1229 SELECT_INTERRUPT(drive);
1231 hwgroup->hwif = hwif;
1232 hwgroup->drive = drive;
1233 drive->sleeping = 0;
1234 drive->service_start = jiffies;
1236 if (blk_queue_plugged(drive->queue)) {
1237 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1238 break;
1241 /*
1242 * we know that the queue isn't empty, but this can happen
1243 * if the q->prep_rq_fn() decides to kill a request
1244 */
1245 rq = elv_next_request(drive->queue);
1246 if (!rq) {
1247 hwgroup->busy = 0;
1248 break;
1251 /*
1252 * Sanity: don't accept a request that isn't a PM request
1253 * if we are currently power managed. This is very important as
1254 * blk_stop_queue() doesn't prevent the elv_next_request()
1255 * above to return us whatever is in the queue. Since we call
1256 * ide_do_request() ourselves, we end up taking requests while
1257 * the queue is blocked...
1259 * We let requests forced at head of queue with ide-preempt
1260 * though. I hope that doesn't happen too much, hopefully not
1261 * unless the subdriver triggers such a thing in its own PM
1262 * state machine.
1264 * We count how many times we loop here to make sure we service
1265 * all drives in the hwgroup without looping for ever
1266 */
1267 if (drive->blocked && !blk_pm_request(rq) && !(rq->flags & REQ_PREEMPT)) {
1268 drive = drive->next ? drive->next : hwgroup->drive;
1269 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1270 goto again;
1271 /* We clear busy, there should be no pending ATA command at this point. */
1272 hwgroup->busy = 0;
1273 break;
1276 hwgroup->rq = rq;
1278 /*
1279 * Some systems have trouble with IDE IRQs arriving while
1280 * the driver is still setting things up. So, here we disable
1281 * the IRQ used by this interface while the request is being started.
1282 * This may look bad at first, but pretty much the same thing
1283 * happens anyway when any interrupt comes in, IDE or otherwise
1284 * -- the kernel masks the IRQ while it is being handled.
1285 */
1286 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1287 disable_irq_nosync(hwif->irq);
1288 spin_unlock(&ide_lock);
1289 local_irq_enable_in_hardirq();
1290 /* allow other IRQs while we start this request */
1291 startstop = start_request(drive, rq);
1292 spin_lock_irq(&ide_lock);
1293 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1294 enable_irq(hwif->irq);
1295 if (startstop == ide_stopped)
1296 hwgroup->busy = 0;
1300 /*
1301 * Passes the stuff to ide_do_request
1302 */
1303 void do_ide_request(request_queue_t *q)
1305 ide_drive_t *drive = q->queuedata;
1307 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1310 /*
1311 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1312 * retry the current request in pio mode instead of risking tossing it
1313 * all away
1314 */
1315 static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1317 ide_hwif_t *hwif = HWIF(drive);
1318 struct request *rq;
1319 ide_startstop_t ret = ide_stopped;
1321 /*
1322 * end current dma transaction
1323 */
1325 if (error < 0) {
1326 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1327 (void)HWIF(drive)->ide_dma_end(drive);
1328 ret = ide_error(drive, "dma timeout error",
1329 hwif->INB(IDE_STATUS_REG));
1330 } else {
1331 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
1332 (void) hwif->ide_dma_timeout(drive);
1335 /*
1336 * disable dma for now, but remember that we did so because of
1337 * a timeout -- we'll reenable after we finish this next request
1338 * (or rather the first chunk of it) in pio.
1339 */
1340 drive->retry_pio++;
1341 drive->state = DMA_PIO_RETRY;
1342 (void) hwif->ide_dma_off_quietly(drive);
1344 /*
1345 * un-busy drive etc (hwgroup->busy is cleared on return) and
1346 * make sure request is sane
1347 */
1348 rq = HWGROUP(drive)->rq;
1349 HWGROUP(drive)->rq = NULL;
1351 rq->errors = 0;
1353 if (!rq->bio)
1354 goto out;
1356 rq->sector = rq->bio->bi_sector;
1357 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1358 rq->hard_cur_sectors = rq->current_nr_sectors;
1359 rq->buffer = bio_data(rq->bio);
1360 out:
1361 return ret;
1364 /**
1365 * ide_timer_expiry - handle lack of an IDE interrupt
1366 * @data: timer callback magic (hwgroup)
1368 * An IDE command has timed out before the expected drive return
1369 * occurred. At this point we attempt to clean up the current
1370 * mess. If the current handler includes an expiry handler then
1371 * we invoke the expiry handler, and providing it is happy the
1372 * work is done. If that fails we apply generic recovery rules
1373 * invoking the handler and checking the drive DMA status. We
1374 * have an excessively incestuous relationship with the DMA
1375 * logic that wants cleaning up.
1376 */
1378 void ide_timer_expiry (unsigned long data)
1380 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1381 ide_handler_t *handler;
1382 ide_expiry_t *expiry;
1383 unsigned long flags;
1384 unsigned long wait = -1;
1386 spin_lock_irqsave(&ide_lock, flags);
1388 if ((handler = hwgroup->handler) == NULL) {
1389 /*
1390 * Either a marginal timeout occurred
1391 * (got the interrupt just as timer expired),
1392 * or we were "sleeping" to give other devices a chance.
1393 * Either way, we don't really want to complain about anything.
1394 */
1395 if (hwgroup->sleeping) {
1396 hwgroup->sleeping = 0;
1397 hwgroup->busy = 0;
1399 } else {
1400 ide_drive_t *drive = hwgroup->drive;
1401 if (!drive) {
1402 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1403 hwgroup->handler = NULL;
1404 } else {
1405 ide_hwif_t *hwif;
1406 ide_startstop_t startstop = ide_stopped;
1407 if (!hwgroup->busy) {
1408 hwgroup->busy = 1; /* paranoia */
1409 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1411 if ((expiry = hwgroup->expiry) != NULL) {
1412 /* continue */
1413 if ((wait = expiry(drive)) > 0) {
1414 /* reset timer */
1415 hwgroup->timer.expires = jiffies + wait;
1416 add_timer(&hwgroup->timer);
1417 spin_unlock_irqrestore(&ide_lock, flags);
1418 return;
1421 hwgroup->handler = NULL;
1422 /*
1423 * We need to simulate a real interrupt when invoking
1424 * the handler() function, which means we need to
1425 * globally mask the specific IRQ:
1426 */
1427 spin_unlock(&ide_lock);
1428 hwif = HWIF(drive);
1429 #if DISABLE_IRQ_NOSYNC
1430 disable_irq_nosync(hwif->irq);
1431 #else
1432 /* disable_irq_nosync ?? */
1433 disable_irq(hwif->irq);
1434 #endif /* DISABLE_IRQ_NOSYNC */
1435 /* local CPU only,
1436 * as if we were handling an interrupt */
1437 local_irq_disable();
1438 if (hwgroup->polling) {
1439 startstop = handler(drive);
1440 } else if (drive_is_ready(drive)) {
1441 if (drive->waiting_for_dma)
1442 (void) hwgroup->hwif->ide_dma_lostirq(drive);
1443 (void)ide_ack_intr(hwif);
1444 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1445 startstop = handler(drive);
1446 } else {
1447 if (drive->waiting_for_dma) {
1448 startstop = ide_dma_timeout_retry(drive, wait);
1449 } else
1450 startstop =
1451 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG));
1453 drive->service_time = jiffies - drive->service_start;
1454 spin_lock_irq(&ide_lock);
1455 enable_irq(hwif->irq);
1456 if (startstop == ide_stopped)
1457 hwgroup->busy = 0;
1460 ide_do_request(hwgroup, IDE_NO_IRQ);
1461 spin_unlock_irqrestore(&ide_lock, flags);
1464 /**
1465 * unexpected_intr - handle an unexpected IDE interrupt
1466 * @irq: interrupt line
1467 * @hwgroup: hwgroup being processed
1469 * There's nothing really useful we can do with an unexpected interrupt,
1470 * other than reading the status register (to clear it), and logging it.
1471 * There should be no way that an irq can happen before we're ready for it,
1472 * so we needn't worry much about losing an "important" interrupt here.
1474 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1475 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1476 * looks "good", we just ignore the interrupt completely.
1478 * This routine assumes __cli() is in effect when called.
1480 * If an unexpected interrupt happens on irq15 while we are handling irq14
1481 * and if the two interfaces are "serialized" (CMD640), then it looks like
1482 * we could screw up by interfering with a new request being set up for
1483 * irq15.
1485 * In reality, this is a non-issue. The new command is not sent unless
1486 * the drive is ready to accept one, in which case we know the drive is
1487 * not trying to interrupt us. And ide_set_handler() is always invoked
1488 * before completing the issuance of any new drive command, so we will not
1489 * be accidentally invoked as a result of any valid command completion
1490 * interrupt.
1492 * Note that we must walk the entire hwgroup here. We know which hwif
1493 * is doing the current command, but we don't know which hwif burped
1494 * mysteriously.
1495 */
1497 static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1499 u8 stat;
1500 ide_hwif_t *hwif = hwgroup->hwif;
1502 /*
1503 * handle the unexpected interrupt
1504 */
1505 do {
1506 if (hwif->irq == irq) {
1507 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1508 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1509 /* Try to not flood the console with msgs */
1510 static unsigned long last_msgtime, count;
1511 ++count;
1512 if (time_after(jiffies, last_msgtime + HZ)) {
1513 last_msgtime = jiffies;
1514 printk(KERN_ERR "%s%s: unexpected interrupt, "
1515 "status=0x%02x, count=%ld\n",
1516 hwif->name,
1517 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1521 } while ((hwif = hwif->next) != hwgroup->hwif);
1524 /**
1525 * ide_intr - default IDE interrupt handler
1526 * @irq: interrupt number
1527 * @dev_id: hwif group
1528 * @regs: unused weirdness from the kernel irq layer
1530 * This is the default IRQ handler for the IDE layer. You should
1531 * not need to override it. If you do be aware it is subtle in
1532 * places
1534 * hwgroup->hwif is the interface in the group currently performing
1535 * a command. hwgroup->drive is the drive and hwgroup->handler is
1536 * the IRQ handler to call. As we issue a command the handlers
1537 * step through multiple states, reassigning the handler to the
1538 * next step in the process. Unlike a smart SCSI controller IDE
1539 * expects the main processor to sequence the various transfer
1540 * stages. We also manage a poll timer to catch up with most
1541 * timeout situations. There are still a few where the handlers
1542 * don't ever decide to give up.
1544 * The handler eventually returns ide_stopped to indicate the
1545 * request completed. At this point we issue the next request
1546 * on the hwgroup and the process begins again.
1547 */
1549 irqreturn_t ide_intr (int irq, void *dev_id, struct pt_regs *regs)
1551 unsigned long flags;
1552 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1553 ide_hwif_t *hwif;
1554 ide_drive_t *drive;
1555 ide_handler_t *handler;
1556 ide_startstop_t startstop;
1558 spin_lock_irqsave(&ide_lock, flags);
1559 hwif = hwgroup->hwif;
1561 if (!ide_ack_intr(hwif)) {
1562 spin_unlock_irqrestore(&ide_lock, flags);
1563 return IRQ_NONE;
1566 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1567 /*
1568 * Not expecting an interrupt from this drive.
1569 * That means this could be:
1570 * (1) an interrupt from another PCI device
1571 * sharing the same PCI INT# as us.
1572 * or (2) a drive just entered sleep or standby mode,
1573 * and is interrupting to let us know.
1574 * or (3) a spurious interrupt of unknown origin.
1576 * For PCI, we cannot tell the difference,
1577 * so in that case we just ignore it and hope it goes away.
1579 * FIXME: unexpected_intr should be hwif-> then we can
1580 * remove all the ifdef PCI crap
1581 */
1582 #ifdef CONFIG_BLK_DEV_IDEPCI
1583 if (hwif->pci_dev && !hwif->pci_dev->vendor)
1584 #endif /* CONFIG_BLK_DEV_IDEPCI */
1586 /*
1587 * Probably not a shared PCI interrupt,
1588 * so we can safely try to do something about it:
1589 */
1590 unexpected_intr(irq, hwgroup);
1591 #ifdef CONFIG_BLK_DEV_IDEPCI
1592 } else {
1593 /*
1594 * Whack the status register, just in case
1595 * we have a leftover pending IRQ.
1596 */
1597 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1598 #endif /* CONFIG_BLK_DEV_IDEPCI */
1600 spin_unlock_irqrestore(&ide_lock, flags);
1601 return IRQ_NONE;
1603 drive = hwgroup->drive;
1604 if (!drive) {
1605 /*
1606 * This should NEVER happen, and there isn't much
1607 * we could do about it here.
1609 * [Note - this can occur if the drive is hot unplugged]
1610 */
1611 spin_unlock_irqrestore(&ide_lock, flags);
1612 return IRQ_HANDLED;
1614 if (!drive_is_ready(drive)) {
1615 /*
1616 * This happens regularly when we share a PCI IRQ with
1617 * another device. Unfortunately, it can also happen
1618 * with some buggy drives that trigger the IRQ before
1619 * their status register is up to date. Hopefully we have
1620 * enough advance overhead that the latter isn't a problem.
1621 */
1622 spin_unlock_irqrestore(&ide_lock, flags);
1623 return IRQ_NONE;
1625 if (!hwgroup->busy) {
1626 hwgroup->busy = 1; /* paranoia */
1627 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1629 hwgroup->handler = NULL;
1630 del_timer(&hwgroup->timer);
1631 spin_unlock(&ide_lock);
1633 if (drive->unmask)
1634 local_irq_enable_in_hardirq();
1635 /* service this interrupt, may set handler for next interrupt */
1636 startstop = handler(drive);
1637 spin_lock_irq(&ide_lock);
1639 /*
1640 * Note that handler() may have set things up for another
1641 * interrupt to occur soon, but it cannot happen until
1642 * we exit from this routine, because it will be the
1643 * same irq as is currently being serviced here, and Linux
1644 * won't allow another of the same (on any CPU) until we return.
1645 */
1646 drive->service_time = jiffies - drive->service_start;
1647 if (startstop == ide_stopped) {
1648 if (hwgroup->handler == NULL) { /* paranoia */
1649 hwgroup->busy = 0;
1650 ide_do_request(hwgroup, hwif->irq);
1651 } else {
1652 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1653 "on exit\n", drive->name);
1656 spin_unlock_irqrestore(&ide_lock, flags);
1657 return IRQ_HANDLED;
1660 /**
1661 * ide_init_drive_cmd - initialize a drive command request
1662 * @rq: request object
1664 * Initialize a request before we fill it in and send it down to
1665 * ide_do_drive_cmd. Commands must be set up by this function. Right
1666 * now it doesn't do a lot, but if that changes abusers will have a
1667 * nasty surprise.
1668 */
1670 void ide_init_drive_cmd (struct request *rq)
1672 memset(rq, 0, sizeof(*rq));
1673 rq->flags = REQ_DRIVE_CMD;
1674 rq->ref_count = 1;
1677 EXPORT_SYMBOL(ide_init_drive_cmd);
1679 /**
1680 * ide_do_drive_cmd - issue IDE special command
1681 * @drive: device to issue command
1682 * @rq: request to issue
1683 * @action: action for processing
1685 * This function issues a special IDE device request
1686 * onto the request queue.
1688 * If action is ide_wait, then the rq is queued at the end of the
1689 * request queue, and the function sleeps until it has been processed.
1690 * This is for use when invoked from an ioctl handler.
1692 * If action is ide_preempt, then the rq is queued at the head of
1693 * the request queue, displacing the currently-being-processed
1694 * request and this function returns immediately without waiting
1695 * for the new rq to be completed. This is VERY DANGEROUS, and is
1696 * intended for careful use by the ATAPI tape/cdrom driver code.
1698 * If action is ide_end, then the rq is queued at the end of the
1699 * request queue, and the function returns immediately without waiting
1700 * for the new rq to be completed. This is again intended for careful
1701 * use by the ATAPI tape/cdrom driver code.
1702 */
1704 int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1706 unsigned long flags;
1707 ide_hwgroup_t *hwgroup = HWGROUP(drive);
1708 DECLARE_COMPLETION_ONSTACK(wait);
1709 int where = ELEVATOR_INSERT_BACK, err;
1710 int must_wait = (action == ide_wait || action == ide_head_wait);
1712 rq->errors = 0;
1713 rq->rq_status = RQ_ACTIVE;
1715 /*
1716 * we need to hold an extra reference to request for safe inspection
1717 * after completion
1718 */
1719 if (must_wait) {
1720 rq->ref_count++;
1721 rq->waiting = &wait;
1722 rq->end_io = blk_end_sync_rq;
1725 spin_lock_irqsave(&ide_lock, flags);
1726 if (action == ide_preempt)
1727 hwgroup->rq = NULL;
1728 if (action == ide_preempt || action == ide_head_wait) {
1729 where = ELEVATOR_INSERT_FRONT;
1730 rq->flags |= REQ_PREEMPT;
1732 __elv_add_request(drive->queue, rq, where, 0);
1733 ide_do_request(hwgroup, IDE_NO_IRQ);
1734 spin_unlock_irqrestore(&ide_lock, flags);
1736 err = 0;
1737 if (must_wait) {
1738 wait_for_completion(&wait);
1739 rq->waiting = NULL;
1740 if (rq->errors)
1741 err = -EIO;
1743 blk_put_request(rq);
1746 return err;
1749 EXPORT_SYMBOL(ide_do_drive_cmd);