blob: 484c50e714464f0c2ded5246fa83ae279fc65b6c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 */
25
26
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#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>
50
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>
56
Adrian Bunka7ff7d42006-02-03 03:04:56 -080057static int __ide_end_request(ide_drive_t *drive, struct request *rq,
Jens Axboe41e9d342007-07-19 08:13:01 +020058 int uptodate, unsigned int nr_bytes)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059{
60 int ret = 1;
61
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 /*
63 * if failfast is set on a request, override number of sectors and
64 * complete the whole request right now
65 */
66 if (blk_noretry_request(rq) && end_io_error(uptodate))
Jens Axboe41e9d342007-07-19 08:13:01 +020067 nr_bytes = rq->hard_nr_sectors << 9;
Linus Torvalds1da177e2005-04-16 15:20:36 -070068
69 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
70 rq->errors = -EIO;
71
72 /*
73 * decide whether to reenable DMA -- 3 is a random magic for now,
74 * if we DMA timeout more than 3 times, just stay in PIO
75 */
76 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
77 drive->state = 0;
78 HWGROUP(drive)->hwif->ide_dma_on(drive);
79 }
80
Jens Axboe41e9d342007-07-19 08:13:01 +020081 if (!end_that_request_chunk(rq, uptodate, nr_bytes)) {
Jens Axboeba027de2006-01-12 20:44:12 +010082 add_disk_randomness(rq->rq_disk);
Hua Zhongce42f192006-10-03 01:14:15 -070083 if (!list_empty(&rq->queuelist))
84 blkdev_dequeue_request(rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 HWGROUP(drive)->rq = NULL;
Jens Axboeba027de2006-01-12 20:44:12 +010086 end_that_request_last(rq, uptodate);
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 ret = 0;
88 }
Jens Axboe8672d572006-01-09 16:03:35 +010089
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 return ret;
91}
Linus Torvalds1da177e2005-04-16 15:20:36 -070092
93/**
94 * ide_end_request - complete an IDE I/O
95 * @drive: IDE device for the I/O
96 * @uptodate:
97 * @nr_sectors: number of sectors completed
98 *
99 * This is our end_request wrapper function. We complete the I/O
100 * update random number input and dequeue the request, which if
101 * it was tagged may be out of order.
102 */
103
104int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
105{
Jens Axboe41e9d342007-07-19 08:13:01 +0200106 unsigned int nr_bytes = nr_sectors << 9;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 struct request *rq;
108 unsigned long flags;
109 int ret = 1;
110
Jens Axboe8672d572006-01-09 16:03:35 +0100111 /*
112 * room for locking improvements here, the calls below don't
113 * need the queue lock held at all
114 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 spin_lock_irqsave(&ide_lock, flags);
116 rq = HWGROUP(drive)->rq;
117
Jens Axboe41e9d342007-07-19 08:13:01 +0200118 if (!nr_bytes) {
119 if (blk_pc_request(rq))
120 nr_bytes = rq->data_len;
121 else
122 nr_bytes = rq->hard_cur_sectors << 9;
123 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124
Jens Axboe41e9d342007-07-19 08:13:01 +0200125 ret = __ide_end_request(drive, rq, uptodate, nr_bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126
127 spin_unlock_irqrestore(&ide_lock, flags);
128 return ret;
129}
130EXPORT_SYMBOL(ide_end_request);
131
132/*
133 * Power Management state machine. This one is rather trivial for now,
134 * we should probably add more, like switching back to PIO on suspend
135 * to help some BIOSes, re-do the door locking on resume, etc...
136 */
137
138enum {
139 ide_pm_flush_cache = ide_pm_state_start_suspend,
140 idedisk_pm_standby,
141
Jason Lunz8c2c0112006-10-03 01:14:26 -0700142 idedisk_pm_restore_pio = ide_pm_state_start_resume,
143 idedisk_pm_idle,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 ide_pm_restore_dma,
145};
146
147static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error)
148{
Jens Axboec00895a2006-09-30 20:29:12 +0200149 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200150
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 if (drive->media != ide_disk)
152 return;
153
Jens Axboead3cadd2006-06-13 08:46:57 +0200154 switch (pm->pm_step) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */
Jens Axboead3cadd2006-06-13 08:46:57 +0200156 if (pm->pm_state == PM_EVENT_FREEZE)
157 pm->pm_step = ide_pm_state_completed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 else
Jens Axboead3cadd2006-06-13 08:46:57 +0200159 pm->pm_step = idedisk_pm_standby;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 break;
161 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */
Jens Axboead3cadd2006-06-13 08:46:57 +0200162 pm->pm_step = ide_pm_state_completed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 break;
Jason Lunz8c2c0112006-10-03 01:14:26 -0700164 case idedisk_pm_restore_pio: /* Resume step 1 complete */
165 pm->pm_step = idedisk_pm_idle;
166 break;
167 case idedisk_pm_idle: /* Resume step 2 (idle) complete */
Jens Axboead3cadd2006-06-13 08:46:57 +0200168 pm->pm_step = ide_pm_restore_dma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 break;
170 }
171}
172
173static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq)
174{
Jens Axboec00895a2006-09-30 20:29:12 +0200175 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 ide_task_t *args = rq->special;
177
178 memset(args, 0, sizeof(*args));
179
Jens Axboead3cadd2006-06-13 08:46:57 +0200180 switch (pm->pm_step) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */
182 if (drive->media != ide_disk)
183 break;
184 /* Not supported? Switch to next step now. */
185 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) {
186 ide_complete_power_step(drive, rq, 0, 0);
187 return ide_stopped;
188 }
189 if (ide_id_has_flush_cache_ext(drive->id))
190 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE_EXT;
191 else
192 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE;
193 args->command_type = IDE_DRIVE_TASK_NO_DATA;
194 args->handler = &task_no_data_intr;
195 return do_rw_taskfile(drive, args);
196
197 case idedisk_pm_standby: /* Suspend step 2 (standby) */
198 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_STANDBYNOW1;
199 args->command_type = IDE_DRIVE_TASK_NO_DATA;
200 args->handler = &task_no_data_intr;
201 return do_rw_taskfile(drive, args);
202
Jason Lunz8c2c0112006-10-03 01:14:26 -0700203 case idedisk_pm_restore_pio: /* Resume step 1 (restore PIO) */
204 if (drive->hwif->tuneproc != NULL)
205 drive->hwif->tuneproc(drive, 255);
Bartlomiej Zolnierkiewicz317a46a2007-05-10 00:01:11 +0200206 /*
207 * skip idedisk_pm_idle for ATAPI devices
208 */
209 if (drive->media != ide_disk)
210 pm->pm_step = ide_pm_restore_dma;
211 else
212 ide_complete_power_step(drive, rq, 0, 0);
Jason Lunz8c2c0112006-10-03 01:14:26 -0700213 return ide_stopped;
214
215 case idedisk_pm_idle: /* Resume step 2 (idle) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_IDLEIMMEDIATE;
217 args->command_type = IDE_DRIVE_TASK_NO_DATA;
218 args->handler = task_no_data_intr;
219 return do_rw_taskfile(drive, args);
220
Jason Lunz8c2c0112006-10-03 01:14:26 -0700221 case ide_pm_restore_dma: /* Resume step 3 (restore DMA) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 /*
223 * Right now, all we do is call hwif->ide_dma_check(drive),
224 * we could be smarter and check for current xfer_speed
225 * in struct drive etc...
226 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 if (drive->hwif->ide_dma_check == NULL)
228 break;
Bartlomiej Zolnierkiewicz793a9722007-05-16 00:51:43 +0200229 drive->hwif->dma_off_quietly(drive);
Bartlomiej Zolnierkiewicz8987d212007-07-20 01:11:56 +0200230 /*
231 * TODO: respect ->using_dma setting
232 */
Bartlomiej Zolnierkiewicz3608b5d2007-02-17 02:40:26 +0100233 ide_set_dma(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 break;
235 }
Jens Axboead3cadd2006-06-13 08:46:57 +0200236 pm->pm_step = ide_pm_state_completed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237 return ide_stopped;
238}
239
240/**
Alan Coxdbe217a2006-06-25 05:47:44 -0700241 * ide_end_dequeued_request - complete an IDE I/O
242 * @drive: IDE device for the I/O
243 * @uptodate:
244 * @nr_sectors: number of sectors completed
245 *
246 * Complete an I/O that is no longer on the request queue. This
247 * typically occurs when we pull the request and issue a REQUEST_SENSE.
248 * We must still finish the old request but we must not tamper with the
249 * queue in the meantime.
250 *
251 * NOTE: This path does not handle barrier, but barrier is not supported
252 * on ide-cd anyway.
253 */
254
255int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
256 int uptodate, int nr_sectors)
257{
258 unsigned long flags;
259 int ret = 1;
260
261 spin_lock_irqsave(&ide_lock, flags);
262
Jens Axboe4aff5e22006-08-10 08:44:47 +0200263 BUG_ON(!blk_rq_started(rq));
Alan Coxdbe217a2006-06-25 05:47:44 -0700264
265 /*
266 * if failfast is set on a request, override number of sectors and
267 * complete the whole request right now
268 */
269 if (blk_noretry_request(rq) && end_io_error(uptodate))
270 nr_sectors = rq->hard_nr_sectors;
271
272 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
273 rq->errors = -EIO;
274
275 /*
276 * decide whether to reenable DMA -- 3 is a random magic for now,
277 * if we DMA timeout more than 3 times, just stay in PIO
278 */
279 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
280 drive->state = 0;
281 HWGROUP(drive)->hwif->ide_dma_on(drive);
282 }
283
284 if (!end_that_request_first(rq, uptodate, nr_sectors)) {
285 add_disk_randomness(rq->rq_disk);
286 if (blk_rq_tagged(rq))
287 blk_queue_end_tag(drive->queue, rq);
288 end_that_request_last(rq, uptodate);
289 ret = 0;
290 }
291 spin_unlock_irqrestore(&ide_lock, flags);
292 return ret;
293}
294EXPORT_SYMBOL_GPL(ide_end_dequeued_request);
295
296
297/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 * ide_complete_pm_request - end the current Power Management request
299 * @drive: target drive
300 * @rq: request
301 *
302 * This function cleans up the current PM request and stops the queue
303 * if necessary.
304 */
305static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
306{
307 unsigned long flags;
308
309#ifdef DEBUG_PM
310 printk("%s: completing PM request, %s\n", drive->name,
311 blk_pm_suspend_request(rq) ? "suspend" : "resume");
312#endif
313 spin_lock_irqsave(&ide_lock, flags);
314 if (blk_pm_suspend_request(rq)) {
315 blk_stop_queue(drive->queue);
316 } else {
317 drive->blocked = 0;
318 blk_start_queue(drive->queue);
319 }
320 blkdev_dequeue_request(rq);
321 HWGROUP(drive)->rq = NULL;
Tejun Heo8ffdc652006-01-06 09:49:03 +0100322 end_that_request_last(rq, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323 spin_unlock_irqrestore(&ide_lock, flags);
324}
325
326/*
327 * FIXME: probably move this somewhere else, name is bad too :)
328 */
329u64 ide_get_error_location(ide_drive_t *drive, char *args)
330{
331 u32 high, low;
332 u8 hcyl, lcyl, sect;
333 u64 sector;
334
335 high = 0;
336 hcyl = args[5];
337 lcyl = args[4];
338 sect = args[3];
339
340 if (ide_id_has_flush_cache_ext(drive->id)) {
341 low = (hcyl << 16) | (lcyl << 8) | sect;
342 HWIF(drive)->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
343 high = ide_read_24(drive);
344 } else {
345 u8 cur = HWIF(drive)->INB(IDE_SELECT_REG);
346 if (cur & 0x40) {
347 high = cur & 0xf;
348 low = (hcyl << 16) | (lcyl << 8) | sect;
349 } else {
350 low = hcyl * drive->head * drive->sect;
351 low += lcyl * drive->sect;
352 low += sect - 1;
353 }
354 }
355
356 sector = ((u64) high << 24) | low;
357 return sector;
358}
359EXPORT_SYMBOL(ide_get_error_location);
360
361/**
362 * ide_end_drive_cmd - end an explicit drive command
363 * @drive: command
364 * @stat: status bits
365 * @err: error bits
366 *
367 * Clean up after success/failure of an explicit drive command.
368 * These get thrown onto the queue so they are synchronized with
369 * real I/O operations on the drive.
370 *
371 * In LBA48 mode we have to read the register set twice to get
372 * all the extra information out.
373 */
374
375void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
376{
377 ide_hwif_t *hwif = HWIF(drive);
378 unsigned long flags;
379 struct request *rq;
380
381 spin_lock_irqsave(&ide_lock, flags);
382 rq = HWGROUP(drive)->rq;
383 spin_unlock_irqrestore(&ide_lock, flags);
384
Jens Axboe4aff5e22006-08-10 08:44:47 +0200385 if (rq->cmd_type == REQ_TYPE_ATA_CMD) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 u8 *args = (u8 *) rq->buffer;
387 if (rq->errors == 0)
388 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
389
390 if (args) {
391 args[0] = stat;
392 args[1] = err;
393 args[2] = hwif->INB(IDE_NSECTOR_REG);
394 }
Jens Axboe4aff5e22006-08-10 08:44:47 +0200395 } else if (rq->cmd_type == REQ_TYPE_ATA_TASK) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 u8 *args = (u8 *) rq->buffer;
397 if (rq->errors == 0)
398 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
399
400 if (args) {
401 args[0] = stat;
402 args[1] = err;
403 args[2] = hwif->INB(IDE_NSECTOR_REG);
404 args[3] = hwif->INB(IDE_SECTOR_REG);
405 args[4] = hwif->INB(IDE_LCYL_REG);
406 args[5] = hwif->INB(IDE_HCYL_REG);
407 args[6] = hwif->INB(IDE_SELECT_REG);
408 }
Jens Axboe4aff5e22006-08-10 08:44:47 +0200409 } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 ide_task_t *args = (ide_task_t *) rq->special;
411 if (rq->errors == 0)
412 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
413
414 if (args) {
415 if (args->tf_in_flags.b.data) {
416 u16 data = hwif->INW(IDE_DATA_REG);
417 args->tfRegister[IDE_DATA_OFFSET] = (data) & 0xFF;
418 args->hobRegister[IDE_DATA_OFFSET] = (data >> 8) & 0xFF;
419 }
420 args->tfRegister[IDE_ERROR_OFFSET] = err;
421 /* be sure we're looking at the low order bits */
422 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG);
423 args->tfRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
424 args->tfRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
425 args->tfRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
426 args->tfRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
427 args->tfRegister[IDE_SELECT_OFFSET] = hwif->INB(IDE_SELECT_REG);
428 args->tfRegister[IDE_STATUS_OFFSET] = stat;
429
430 if (drive->addressing == 1) {
431 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
432 args->hobRegister[IDE_FEATURE_OFFSET] = hwif->INB(IDE_FEATURE_REG);
433 args->hobRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
434 args->hobRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
435 args->hobRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
436 args->hobRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
437 }
438 }
439 } else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200440 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441#ifdef DEBUG_PM
442 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
443 drive->name, rq->pm->pm_step, stat, err);
444#endif
445 ide_complete_power_step(drive, rq, stat, err);
Jens Axboead3cadd2006-06-13 08:46:57 +0200446 if (pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 ide_complete_pm_request(drive, rq);
448 return;
449 }
450
451 spin_lock_irqsave(&ide_lock, flags);
452 blkdev_dequeue_request(rq);
453 HWGROUP(drive)->rq = NULL;
454 rq->errors = err;
Tejun Heo8ffdc652006-01-06 09:49:03 +0100455 end_that_request_last(rq, !rq->errors);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 spin_unlock_irqrestore(&ide_lock, flags);
457}
458
459EXPORT_SYMBOL(ide_end_drive_cmd);
460
461/**
462 * try_to_flush_leftover_data - flush junk
463 * @drive: drive to flush
464 *
465 * try_to_flush_leftover_data() is invoked in response to a drive
466 * unexpectedly having its DRQ_STAT bit set. As an alternative to
467 * resetting the drive, this routine tries to clear the condition
468 * by read a sector's worth of data from the drive. Of course,
469 * this may not help if the drive is *waiting* for data from *us*.
470 */
471static void try_to_flush_leftover_data (ide_drive_t *drive)
472{
473 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;
474
475 if (drive->media != ide_disk)
476 return;
477 while (i > 0) {
478 u32 buffer[16];
479 u32 wcount = (i > 16) ? 16 : i;
480
481 i -= wcount;
482 HWIF(drive)->ata_input_data(drive, buffer, wcount);
483 }
484}
485
486static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
487{
488 if (rq->rq_disk) {
489 ide_driver_t *drv;
490
491 drv = *(ide_driver_t **)rq->rq_disk->private_data;
492 drv->end_request(drive, 0, 0);
493 } else
494 ide_end_request(drive, 0, 0);
495}
496
497static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
498{
499 ide_hwif_t *hwif = drive->hwif;
500
501 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
502 /* other bits are useless when BUSY */
503 rq->errors |= ERROR_RESET;
504 } else if (stat & ERR_STAT) {
505 /* err has different meaning on cdrom and tape */
506 if (err == ABRT_ERR) {
507 if (drive->select.b.lba &&
508 /* some newer drives don't support WIN_SPECIFY */
509 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
510 return ide_stopped;
511 } else if ((err & BAD_CRC) == BAD_CRC) {
512 /* UDMA crc error, just retry the operation */
513 drive->crc_count++;
514 } else if (err & (BBD_ERR | ECC_ERR)) {
515 /* retries won't help these */
516 rq->errors = ERROR_MAX;
517 } else if (err & TRK0_ERR) {
518 /* help it find track zero */
519 rq->errors |= ERROR_RECAL;
520 }
521 }
522
Alan Coxda574af2006-06-28 04:27:01 -0700523 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ && hwif->err_stops_fifo == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 try_to_flush_leftover_data(drive);
525
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200526 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 ide_kill_rq(drive, rq);
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200528 return ide_stopped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 }
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200530
531 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
532 rq->errors |= ERROR_RESET;
533
534 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
535 ++rq->errors;
536 return ide_do_reset(drive);
537 }
538
539 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
540 drive->special.b.recalibrate = 1;
541
542 ++rq->errors;
543
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544 return ide_stopped;
545}
546
547static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
548{
549 ide_hwif_t *hwif = drive->hwif;
550
551 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
552 /* other bits are useless when BUSY */
553 rq->errors |= ERROR_RESET;
554 } else {
555 /* add decoding error stuff */
556 }
557
558 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
559 /* force an abort */
560 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
561
562 if (rq->errors >= ERROR_MAX) {
563 ide_kill_rq(drive, rq);
564 } else {
565 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
566 ++rq->errors;
567 return ide_do_reset(drive);
568 }
569 ++rq->errors;
570 }
571
572 return ide_stopped;
573}
574
575ide_startstop_t
576__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
577{
578 if (drive->media == ide_disk)
579 return ide_ata_error(drive, rq, stat, err);
580 return ide_atapi_error(drive, rq, stat, err);
581}
582
583EXPORT_SYMBOL_GPL(__ide_error);
584
585/**
586 * ide_error - handle an error on the IDE
587 * @drive: drive the error occurred on
588 * @msg: message to report
589 * @stat: status bits
590 *
591 * ide_error() takes action based on the error returned by the drive.
592 * For normal I/O that may well include retries. We deal with
593 * both new-style (taskfile) and old style command handling here.
594 * In the case of taskfile command handling there is work left to
595 * do
596 */
597
598ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
599{
600 struct request *rq;
601 u8 err;
602
603 err = ide_dump_status(drive, msg, stat);
604
605 if ((rq = HWGROUP(drive)->rq) == NULL)
606 return ide_stopped;
607
608 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200609 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 rq->errors = 1;
611 ide_end_drive_cmd(drive, stat, err);
612 return ide_stopped;
613 }
614
615 if (rq->rq_disk) {
616 ide_driver_t *drv;
617
618 drv = *(ide_driver_t **)rq->rq_disk->private_data;
619 return drv->error(drive, rq, stat, err);
620 } else
621 return __ide_error(drive, rq, stat, err);
622}
623
624EXPORT_SYMBOL_GPL(ide_error);
625
626ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
627{
628 if (drive->media != ide_disk)
629 rq->errors |= ERROR_RESET;
630
631 ide_kill_rq(drive, rq);
632
633 return ide_stopped;
634}
635
636EXPORT_SYMBOL_GPL(__ide_abort);
637
638/**
Adrian Bunk338cec32005-09-10 00:26:54 -0700639 * ide_abort - abort pending IDE operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 * @drive: drive the error occurred on
641 * @msg: message to report
642 *
643 * ide_abort kills and cleans up when we are about to do a
644 * host initiated reset on active commands. Longer term we
645 * want handlers to have sensible abort handling themselves
646 *
647 * This differs fundamentally from ide_error because in
648 * this case the command is doing just fine when we
649 * blow it away.
650 */
651
652ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
653{
654 struct request *rq;
655
656 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
657 return ide_stopped;
658
659 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200660 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 rq->errors = 1;
662 ide_end_drive_cmd(drive, BUSY_STAT, 0);
663 return ide_stopped;
664 }
665
666 if (rq->rq_disk) {
667 ide_driver_t *drv;
668
669 drv = *(ide_driver_t **)rq->rq_disk->private_data;
670 return drv->abort(drive, rq);
671 } else
672 return __ide_abort(drive, rq);
673}
674
675/**
676 * ide_cmd - issue a simple drive command
677 * @drive: drive the command is for
678 * @cmd: command byte
679 * @nsect: sector byte
680 * @handler: handler for the command completion
681 *
682 * Issue a simple drive command with interrupts.
683 * The drive must be selected beforehand.
684 */
685
686static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect,
687 ide_handler_t *handler)
688{
689 ide_hwif_t *hwif = HWIF(drive);
690 if (IDE_CONTROL_REG)
691 hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */
692 SELECT_MASK(drive,0);
693 hwif->OUTB(nsect,IDE_NSECTOR_REG);
694 ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL);
695}
696
697/**
698 * drive_cmd_intr - drive command completion interrupt
699 * @drive: drive the completion interrupt occurred on
700 *
701 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
Adrian Bunk338cec32005-09-10 00:26:54 -0700702 * We do any necessary data reading and then wait for the drive to
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 * go non busy. At that point we may read the error data and complete
704 * the request
705 */
706
707static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
708{
709 struct request *rq = HWGROUP(drive)->rq;
710 ide_hwif_t *hwif = HWIF(drive);
711 u8 *args = (u8 *) rq->buffer;
712 u8 stat = hwif->INB(IDE_STATUS_REG);
713 int retries = 10;
714
Ingo Molnar366c7f52006-07-03 00:25:25 -0700715 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716 if ((stat & DRQ_STAT) && args && args[3]) {
717 u8 io_32bit = drive->io_32bit;
718 drive->io_32bit = 0;
719 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
720 drive->io_32bit = io_32bit;
721 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
722 udelay(100);
723 }
724
725 if (!OK_STAT(stat, READY_STAT, BAD_STAT))
726 return ide_error(drive, "drive_cmd", stat);
727 /* calls ide_end_drive_cmd */
728 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
729 return ide_stopped;
730}
731
732static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task)
733{
734 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
735 task->tfRegister[IDE_SECTOR_OFFSET] = drive->sect;
736 task->tfRegister[IDE_LCYL_OFFSET] = drive->cyl;
737 task->tfRegister[IDE_HCYL_OFFSET] = drive->cyl>>8;
738 task->tfRegister[IDE_SELECT_OFFSET] = ((drive->head-1)|drive->select.all)&0xBF;
739 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY;
740
741 task->handler = &set_geometry_intr;
742}
743
744static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task)
745{
746 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
747 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE;
748
749 task->handler = &recal_intr;
750}
751
752static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task)
753{
754 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req;
755 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT;
756
757 task->handler = &set_multmode_intr;
758}
759
760static ide_startstop_t ide_disk_special(ide_drive_t *drive)
761{
762 special_t *s = &drive->special;
763 ide_task_t args;
764
765 memset(&args, 0, sizeof(ide_task_t));
766 args.command_type = IDE_DRIVE_TASK_NO_DATA;
767
768 if (s->b.set_geometry) {
769 s->b.set_geometry = 0;
770 ide_init_specify_cmd(drive, &args);
771 } else if (s->b.recalibrate) {
772 s->b.recalibrate = 0;
773 ide_init_restore_cmd(drive, &args);
774 } else if (s->b.set_multmode) {
775 s->b.set_multmode = 0;
776 if (drive->mult_req > drive->id->max_multsect)
777 drive->mult_req = drive->id->max_multsect;
778 ide_init_setmult_cmd(drive, &args);
779 } else if (s->all) {
780 int special = s->all;
781 s->all = 0;
782 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
783 return ide_stopped;
784 }
785
786 do_rw_taskfile(drive, &args);
787
788 return ide_started;
789}
790
791/**
792 * do_special - issue some special commands
793 * @drive: drive the command is for
794 *
795 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
796 * commands to a drive. It used to do much more, but has been scaled
797 * back.
798 */
799
800static ide_startstop_t do_special (ide_drive_t *drive)
801{
802 special_t *s = &drive->special;
803
804#ifdef DEBUG
805 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
806#endif
807 if (s->b.set_tune) {
808 s->b.set_tune = 0;
809 if (HWIF(drive)->tuneproc != NULL)
810 HWIF(drive)->tuneproc(drive, drive->tune_req);
811 return ide_stopped;
812 } else {
813 if (drive->media == ide_disk)
814 return ide_disk_special(drive);
815
816 s->all = 0;
817 drive->mult_req = 0;
818 return ide_stopped;
819 }
820}
821
822void ide_map_sg(ide_drive_t *drive, struct request *rq)
823{
824 ide_hwif_t *hwif = drive->hwif;
825 struct scatterlist *sg = hwif->sg_table;
826
827 if (hwif->sg_mapped) /* needed by ide-scsi */
828 return;
829
Jens Axboe4aff5e22006-08-10 08:44:47 +0200830 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
832 } else {
833 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
834 hwif->sg_nents = 1;
835 }
836}
837
838EXPORT_SYMBOL_GPL(ide_map_sg);
839
840void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
841{
842 ide_hwif_t *hwif = drive->hwif;
843
844 hwif->nsect = hwif->nleft = rq->nr_sectors;
845 hwif->cursg = hwif->cursg_ofs = 0;
846}
847
848EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
849
850/**
851 * execute_drive_command - issue special drive command
Adrian Bunk338cec32005-09-10 00:26:54 -0700852 * @drive: the drive to issue the command on
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853 * @rq: the request structure holding the command
854 *
855 * execute_drive_cmd() issues a special drive command, usually
856 * initiated by ioctl() from the external hdparm program. The
857 * command can be a drive command, drive task or taskfile
858 * operation. Weirdly you can call it with NULL to wait for
859 * all commands to finish. Don't do this as that is due to change
860 */
861
862static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
863 struct request *rq)
864{
865 ide_hwif_t *hwif = HWIF(drive);
Jens Axboe4aff5e22006-08-10 08:44:47 +0200866 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 ide_task_t *args = rq->special;
868
869 if (!args)
870 goto done;
871
872 hwif->data_phase = args->data_phase;
873
874 switch (hwif->data_phase) {
875 case TASKFILE_MULTI_OUT:
876 case TASKFILE_OUT:
877 case TASKFILE_MULTI_IN:
878 case TASKFILE_IN:
879 ide_init_sg_cmd(drive, rq);
880 ide_map_sg(drive, rq);
881 default:
882 break;
883 }
884
885 if (args->tf_out_flags.all != 0)
886 return flagged_taskfile(drive, args);
887 return do_rw_taskfile(drive, args);
Jens Axboe4aff5e22006-08-10 08:44:47 +0200888 } else if (rq->cmd_type == REQ_TYPE_ATA_TASK) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 u8 *args = rq->buffer;
890 u8 sel;
891
892 if (!args)
893 goto done;
894#ifdef DEBUG
895 printk("%s: DRIVE_TASK_CMD ", drive->name);
896 printk("cmd=0x%02x ", args[0]);
897 printk("fr=0x%02x ", args[1]);
898 printk("ns=0x%02x ", args[2]);
899 printk("sc=0x%02x ", args[3]);
900 printk("lcyl=0x%02x ", args[4]);
901 printk("hcyl=0x%02x ", args[5]);
902 printk("sel=0x%02x\n", args[6]);
903#endif
904 hwif->OUTB(args[1], IDE_FEATURE_REG);
905 hwif->OUTB(args[3], IDE_SECTOR_REG);
906 hwif->OUTB(args[4], IDE_LCYL_REG);
907 hwif->OUTB(args[5], IDE_HCYL_REG);
908 sel = (args[6] & ~0x10);
909 if (drive->select.b.unit)
910 sel |= 0x10;
911 hwif->OUTB(sel, IDE_SELECT_REG);
912 ide_cmd(drive, args[0], args[2], &drive_cmd_intr);
913 return ide_started;
Jens Axboe4aff5e22006-08-10 08:44:47 +0200914 } else if (rq->cmd_type == REQ_TYPE_ATA_CMD) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 u8 *args = rq->buffer;
916
917 if (!args)
918 goto done;
919#ifdef DEBUG
920 printk("%s: DRIVE_CMD ", drive->name);
921 printk("cmd=0x%02x ", args[0]);
922 printk("sc=0x%02x ", args[1]);
923 printk("fr=0x%02x ", args[2]);
924 printk("xx=0x%02x\n", args[3]);
925#endif
926 if (args[0] == WIN_SMART) {
927 hwif->OUTB(0x4f, IDE_LCYL_REG);
928 hwif->OUTB(0xc2, IDE_HCYL_REG);
929 hwif->OUTB(args[2],IDE_FEATURE_REG);
930 hwif->OUTB(args[1],IDE_SECTOR_REG);
931 ide_cmd(drive, args[0], args[3], &drive_cmd_intr);
932 return ide_started;
933 }
934 hwif->OUTB(args[2],IDE_FEATURE_REG);
935 ide_cmd(drive, args[0], args[1], &drive_cmd_intr);
936 return ide_started;
937 }
938
939done:
940 /*
941 * NULL is actually a valid way of waiting for
942 * all current requests to be flushed from the queue.
943 */
944#ifdef DEBUG
945 printk("%s: DRIVE_CMD (null)\n", drive->name);
946#endif
947 ide_end_drive_cmd(drive,
948 hwif->INB(IDE_STATUS_REG),
949 hwif->INB(IDE_ERROR_REG));
950 return ide_stopped;
951}
952
Jens Axboead3cadd2006-06-13 08:46:57 +0200953static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
954{
Jens Axboec00895a2006-09-30 20:29:12 +0200955 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200956
957 if (blk_pm_suspend_request(rq) &&
958 pm->pm_step == ide_pm_state_start_suspend)
959 /* Mark drive blocked when starting the suspend sequence. */
960 drive->blocked = 1;
961 else if (blk_pm_resume_request(rq) &&
962 pm->pm_step == ide_pm_state_start_resume) {
963 /*
964 * The first thing we do on wakeup is to wait for BSY bit to
965 * go away (with a looong timeout) as a drive on this hwif may
966 * just be POSTing itself.
967 * We do that before even selecting as the "other" device on
968 * the bus may be broken enough to walk on our toes at this
969 * point.
970 */
971 int rc;
972#ifdef DEBUG_PM
973 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
974#endif
975 rc = ide_wait_not_busy(HWIF(drive), 35000);
976 if (rc)
977 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
978 SELECT_DRIVE(drive);
979 HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]);
Al Boldi178184b2006-06-26 00:26:13 -0700980 rc = ide_wait_not_busy(HWIF(drive), 100000);
Jens Axboead3cadd2006-06-13 08:46:57 +0200981 if (rc)
982 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
983 }
984}
985
Linus Torvalds1da177e2005-04-16 15:20:36 -0700986/**
987 * start_request - start of I/O and command issuing for IDE
988 *
989 * start_request() initiates handling of a new I/O request. It
990 * accepts commands and I/O (read/write) requests. It also does
991 * the final remapping for weird stuff like EZDrive. Once
992 * device mapper can work sector level the EZDrive stuff can go away
993 *
994 * FIXME: this function needs a rename
995 */
996
997static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
998{
999 ide_startstop_t startstop;
1000 sector_t block;
1001
Jens Axboe4aff5e22006-08-10 08:44:47 +02001002 BUG_ON(!blk_rq_started(rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003
1004#ifdef DEBUG
1005 printk("%s: start_request: current=0x%08lx\n",
1006 HWIF(drive)->name, (unsigned long) rq);
1007#endif
1008
1009 /* bail early if we've exceeded max_failures */
1010 if (drive->max_failures && (drive->failures > drive->max_failures)) {
1011 goto kill_rq;
1012 }
1013
1014 block = rq->sector;
1015 if (blk_fs_request(rq) &&
1016 (drive->media == ide_disk || drive->media == ide_floppy)) {
1017 block += drive->sect0;
1018 }
1019 /* Yecch - this will shift the entire interval,
1020 possibly killing some innocent following sector */
1021 if (block == 0 && drive->remap_0_to_1 == 1)
1022 block = 1; /* redirect MBR access to EZ-Drive partn table */
1023
Jens Axboead3cadd2006-06-13 08:46:57 +02001024 if (blk_pm_request(rq))
1025 ide_check_pm_state(drive, rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001026
1027 SELECT_DRIVE(drive);
1028 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
1029 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
1030 return startstop;
1031 }
1032 if (!drive->special.all) {
1033 ide_driver_t *drv;
1034
Suleiman Souhlal513daad2007-03-26 23:03:20 +02001035 /*
1036 * We reset the drive so we need to issue a SETFEATURES.
1037 * Do it _after_ do_special() restored device parameters.
1038 */
1039 if (drive->current_speed == 0xff)
1040 ide_config_drive_speed(drive, drive->desired_speed);
1041
Jens Axboe4aff5e22006-08-10 08:44:47 +02001042 if (rq->cmd_type == REQ_TYPE_ATA_CMD ||
1043 rq->cmd_type == REQ_TYPE_ATA_TASK ||
1044 rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001045 return execute_drive_cmd(drive, rq);
1046 else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +02001047 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001048#ifdef DEBUG_PM
1049 printk("%s: start_power_step(step: %d)\n",
1050 drive->name, rq->pm->pm_step);
1051#endif
1052 startstop = ide_start_power_step(drive, rq);
1053 if (startstop == ide_stopped &&
Jens Axboead3cadd2006-06-13 08:46:57 +02001054 pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055 ide_complete_pm_request(drive, rq);
1056 return startstop;
1057 }
1058
1059 drv = *(ide_driver_t **)rq->rq_disk->private_data;
1060 return drv->do_request(drive, rq, block);
1061 }
1062 return do_special(drive);
1063kill_rq:
1064 ide_kill_rq(drive, rq);
1065 return ide_stopped;
1066}
1067
1068/**
1069 * ide_stall_queue - pause an IDE device
1070 * @drive: drive to stall
1071 * @timeout: time to stall for (jiffies)
1072 *
1073 * ide_stall_queue() can be used by a drive to give excess bandwidth back
1074 * to the hwgroup by sleeping for timeout jiffies.
1075 */
1076
1077void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
1078{
1079 if (timeout > WAIT_WORSTCASE)
1080 timeout = WAIT_WORSTCASE;
1081 drive->sleep = timeout + jiffies;
1082 drive->sleeping = 1;
1083}
1084
1085EXPORT_SYMBOL(ide_stall_queue);
1086
1087#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
1088
1089/**
1090 * choose_drive - select a drive to service
1091 * @hwgroup: hardware group to select on
1092 *
1093 * choose_drive() selects the next drive which will be serviced.
1094 * This is necessary because the IDE layer can't issue commands
1095 * to both drives on the same cable, unlike SCSI.
1096 */
1097
1098static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
1099{
1100 ide_drive_t *drive, *best;
1101
1102repeat:
1103 best = NULL;
1104 drive = hwgroup->drive;
1105
1106 /*
1107 * drive is doing pre-flush, ordered write, post-flush sequence. even
1108 * though that is 3 requests, it must be seen as a single transaction.
1109 * we must not preempt this drive until that is complete
1110 */
1111 if (blk_queue_flushing(drive->queue)) {
1112 /*
1113 * small race where queue could get replugged during
1114 * the 3-request flush cycle, just yank the plug since
1115 * we want it to finish asap
1116 */
1117 blk_remove_plug(drive->queue);
1118 return drive;
1119 }
1120
1121 do {
1122 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
1123 && !elv_queue_empty(drive->queue)) {
1124 if (!best
1125 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
1126 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
1127 {
1128 if (!blk_queue_plugged(drive->queue))
1129 best = drive;
1130 }
1131 }
1132 } while ((drive = drive->next) != hwgroup->drive);
1133 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1134 long t = (signed long)(WAKEUP(best) - jiffies);
1135 if (t >= WAIT_MIN_SLEEP) {
1136 /*
1137 * We *may* have some time to spare, but first let's see if
1138 * someone can potentially benefit from our nice mood today..
1139 */
1140 drive = best->next;
1141 do {
1142 if (!drive->sleeping
1143 && time_before(jiffies - best->service_time, WAKEUP(drive))
1144 && time_before(WAKEUP(drive), jiffies + t))
1145 {
1146 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1147 goto repeat;
1148 }
1149 } while ((drive = drive->next) != best);
1150 }
1151 }
1152 return best;
1153}
1154
1155/*
1156 * Issue a new request to a drive from hwgroup
1157 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1158 *
1159 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1160 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1161 * may have both interfaces in a single hwgroup to "serialize" access.
1162 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1163 * together into one hwgroup for serialized access.
1164 *
1165 * Note also that several hwgroups can end up sharing a single IRQ,
1166 * possibly along with many other devices. This is especially common in
1167 * PCI-based systems with off-board IDE controller cards.
1168 *
1169 * The IDE driver uses the single global ide_lock spinlock to protect
1170 * access to the request queues, and to protect the hwgroup->busy flag.
1171 *
1172 * The first thread into the driver for a particular hwgroup sets the
1173 * hwgroup->busy flag to indicate that this hwgroup is now active,
1174 * and then initiates processing of the top request from the request queue.
1175 *
1176 * Other threads attempting entry notice the busy setting, and will simply
1177 * queue their new requests and exit immediately. Note that hwgroup->busy
1178 * remains set even when the driver is merely awaiting the next interrupt.
1179 * Thus, the meaning is "this hwgroup is busy processing a request".
1180 *
1181 * When processing of a request completes, the completing thread or IRQ-handler
1182 * will start the next request from the queue. If no more work remains,
1183 * the driver will clear the hwgroup->busy flag and exit.
1184 *
1185 * The ide_lock (spinlock) is used to protect all access to the
1186 * hwgroup->busy flag, but is otherwise not needed for most processing in
1187 * the driver. This makes the driver much more friendlier to shared IRQs
1188 * than previous designs, while remaining 100% (?) SMP safe and capable.
1189 */
1190static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1191{
1192 ide_drive_t *drive;
1193 ide_hwif_t *hwif;
1194 struct request *rq;
1195 ide_startstop_t startstop;
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001196 int loops = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001197
1198 /* for atari only: POSSIBLY BROKEN HERE(?) */
1199 ide_get_lock(ide_intr, hwgroup);
1200
1201 /* caller must own ide_lock */
1202 BUG_ON(!irqs_disabled());
1203
1204 while (!hwgroup->busy) {
1205 hwgroup->busy = 1;
1206 drive = choose_drive(hwgroup);
1207 if (drive == NULL) {
1208 int sleeping = 0;
1209 unsigned long sleep = 0; /* shut up, gcc */
1210 hwgroup->rq = NULL;
1211 drive = hwgroup->drive;
1212 do {
1213 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1214 sleeping = 1;
1215 sleep = drive->sleep;
1216 }
1217 } while ((drive = drive->next) != hwgroup->drive);
1218 if (sleeping) {
1219 /*
1220 * Take a short snooze, and then wake up this hwgroup again.
1221 * This gives other hwgroups on the same a chance to
1222 * play fairly with us, just in case there are big differences
1223 * in relative throughputs.. don't want to hog the cpu too much.
1224 */
1225 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1226 sleep = jiffies + WAIT_MIN_SLEEP;
1227#if 1
1228 if (timer_pending(&hwgroup->timer))
1229 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1230#endif
1231 /* so that ide_timer_expiry knows what to do */
1232 hwgroup->sleeping = 1;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001233 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234 mod_timer(&hwgroup->timer, sleep);
1235 /* we purposely leave hwgroup->busy==1
1236 * while sleeping */
1237 } else {
1238 /* Ugly, but how can we sleep for the lock
1239 * otherwise? perhaps from tq_disk?
1240 */
1241
1242 /* for atari only */
1243 ide_release_lock();
1244 hwgroup->busy = 0;
1245 }
1246
1247 /* no more work for this hwgroup (for now) */
1248 return;
1249 }
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001250 again:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001251 hwif = HWIF(drive);
1252 if (hwgroup->hwif->sharing_irq &&
1253 hwif != hwgroup->hwif &&
1254 hwif->io_ports[IDE_CONTROL_OFFSET]) {
1255 /* set nIEN for previous hwif */
1256 SELECT_INTERRUPT(drive);
1257 }
1258 hwgroup->hwif = hwif;
1259 hwgroup->drive = drive;
1260 drive->sleeping = 0;
1261 drive->service_start = jiffies;
1262
1263 if (blk_queue_plugged(drive->queue)) {
1264 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1265 break;
1266 }
1267
1268 /*
1269 * we know that the queue isn't empty, but this can happen
1270 * if the q->prep_rq_fn() decides to kill a request
1271 */
1272 rq = elv_next_request(drive->queue);
1273 if (!rq) {
1274 hwgroup->busy = 0;
1275 break;
1276 }
1277
1278 /*
1279 * Sanity: don't accept a request that isn't a PM request
1280 * if we are currently power managed. This is very important as
1281 * blk_stop_queue() doesn't prevent the elv_next_request()
1282 * above to return us whatever is in the queue. Since we call
1283 * ide_do_request() ourselves, we end up taking requests while
1284 * the queue is blocked...
1285 *
1286 * We let requests forced at head of queue with ide-preempt
1287 * though. I hope that doesn't happen too much, hopefully not
1288 * unless the subdriver triggers such a thing in its own PM
1289 * state machine.
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001290 *
1291 * We count how many times we loop here to make sure we service
1292 * all drives in the hwgroup without looping for ever
Linus Torvalds1da177e2005-04-16 15:20:36 -07001293 */
Jens Axboe4aff5e22006-08-10 08:44:47 +02001294 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) {
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001295 drive = drive->next ? drive->next : hwgroup->drive;
1296 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1297 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298 /* We clear busy, there should be no pending ATA command at this point. */
1299 hwgroup->busy = 0;
1300 break;
1301 }
1302
1303 hwgroup->rq = rq;
1304
1305 /*
1306 * Some systems have trouble with IDE IRQs arriving while
1307 * the driver is still setting things up. So, here we disable
1308 * the IRQ used by this interface while the request is being started.
1309 * This may look bad at first, but pretty much the same thing
1310 * happens anyway when any interrupt comes in, IDE or otherwise
1311 * -- the kernel masks the IRQ while it is being handled.
1312 */
1313 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1314 disable_irq_nosync(hwif->irq);
1315 spin_unlock(&ide_lock);
Ingo Molnar366c7f52006-07-03 00:25:25 -07001316 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001317 /* allow other IRQs while we start this request */
1318 startstop = start_request(drive, rq);
1319 spin_lock_irq(&ide_lock);
1320 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1321 enable_irq(hwif->irq);
1322 if (startstop == ide_stopped)
1323 hwgroup->busy = 0;
1324 }
1325}
1326
1327/*
1328 * Passes the stuff to ide_do_request
1329 */
1330void do_ide_request(request_queue_t *q)
1331{
1332 ide_drive_t *drive = q->queuedata;
1333
1334 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1335}
1336
1337/*
1338 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1339 * retry the current request in pio mode instead of risking tossing it
1340 * all away
1341 */
1342static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1343{
1344 ide_hwif_t *hwif = HWIF(drive);
1345 struct request *rq;
1346 ide_startstop_t ret = ide_stopped;
1347
1348 /*
1349 * end current dma transaction
1350 */
1351
1352 if (error < 0) {
1353 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1354 (void)HWIF(drive)->ide_dma_end(drive);
1355 ret = ide_error(drive, "dma timeout error",
1356 hwif->INB(IDE_STATUS_REG));
1357 } else {
1358 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
Sergei Shtylyovc283f5d2007-07-09 23:17:54 +02001359 hwif->dma_timeout(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 }
1361
1362 /*
1363 * disable dma for now, but remember that we did so because of
1364 * a timeout -- we'll reenable after we finish this next request
1365 * (or rather the first chunk of it) in pio.
1366 */
1367 drive->retry_pio++;
1368 drive->state = DMA_PIO_RETRY;
Bartlomiej Zolnierkiewicz7469aaf2007-02-17 02:40:26 +01001369 hwif->dma_off_quietly(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370
1371 /*
1372 * un-busy drive etc (hwgroup->busy is cleared on return) and
1373 * make sure request is sane
1374 */
1375 rq = HWGROUP(drive)->rq;
Hua Zhongce42f192006-10-03 01:14:15 -07001376
1377 if (!rq)
1378 goto out;
1379
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380 HWGROUP(drive)->rq = NULL;
1381
1382 rq->errors = 0;
1383
1384 if (!rq->bio)
1385 goto out;
1386
1387 rq->sector = rq->bio->bi_sector;
1388 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1389 rq->hard_cur_sectors = rq->current_nr_sectors;
1390 rq->buffer = bio_data(rq->bio);
1391out:
1392 return ret;
1393}
1394
1395/**
1396 * ide_timer_expiry - handle lack of an IDE interrupt
1397 * @data: timer callback magic (hwgroup)
1398 *
1399 * An IDE command has timed out before the expected drive return
1400 * occurred. At this point we attempt to clean up the current
1401 * mess. If the current handler includes an expiry handler then
1402 * we invoke the expiry handler, and providing it is happy the
1403 * work is done. If that fails we apply generic recovery rules
1404 * invoking the handler and checking the drive DMA status. We
1405 * have an excessively incestuous relationship with the DMA
1406 * logic that wants cleaning up.
1407 */
1408
1409void ide_timer_expiry (unsigned long data)
1410{
1411 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1412 ide_handler_t *handler;
1413 ide_expiry_t *expiry;
1414 unsigned long flags;
1415 unsigned long wait = -1;
1416
1417 spin_lock_irqsave(&ide_lock, flags);
1418
Suleiman Souhlal23450312007-04-10 22:38:37 +02001419 if (((handler = hwgroup->handler) == NULL) ||
1420 (hwgroup->req_gen != hwgroup->req_gen_timer)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421 /*
1422 * Either a marginal timeout occurred
1423 * (got the interrupt just as timer expired),
1424 * or we were "sleeping" to give other devices a chance.
1425 * Either way, we don't really want to complain about anything.
1426 */
1427 if (hwgroup->sleeping) {
1428 hwgroup->sleeping = 0;
1429 hwgroup->busy = 0;
1430 }
1431 } else {
1432 ide_drive_t *drive = hwgroup->drive;
1433 if (!drive) {
1434 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1435 hwgroup->handler = NULL;
1436 } else {
1437 ide_hwif_t *hwif;
1438 ide_startstop_t startstop = ide_stopped;
1439 if (!hwgroup->busy) {
1440 hwgroup->busy = 1; /* paranoia */
1441 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1442 }
1443 if ((expiry = hwgroup->expiry) != NULL) {
1444 /* continue */
1445 if ((wait = expiry(drive)) > 0) {
1446 /* reset timer */
1447 hwgroup->timer.expires = jiffies + wait;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001448 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001449 add_timer(&hwgroup->timer);
1450 spin_unlock_irqrestore(&ide_lock, flags);
1451 return;
1452 }
1453 }
1454 hwgroup->handler = NULL;
1455 /*
1456 * We need to simulate a real interrupt when invoking
1457 * the handler() function, which means we need to
1458 * globally mask the specific IRQ:
1459 */
1460 spin_unlock(&ide_lock);
1461 hwif = HWIF(drive);
1462#if DISABLE_IRQ_NOSYNC
1463 disable_irq_nosync(hwif->irq);
1464#else
1465 /* disable_irq_nosync ?? */
1466 disable_irq(hwif->irq);
1467#endif /* DISABLE_IRQ_NOSYNC */
1468 /* local CPU only,
1469 * as if we were handling an interrupt */
1470 local_irq_disable();
1471 if (hwgroup->polling) {
1472 startstop = handler(drive);
1473 } else if (drive_is_ready(drive)) {
1474 if (drive->waiting_for_dma)
Sergei Shtylyov841d2a92007-07-09 23:17:54 +02001475 hwgroup->hwif->dma_lost_irq(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476 (void)ide_ack_intr(hwif);
1477 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1478 startstop = handler(drive);
1479 } else {
1480 if (drive->waiting_for_dma) {
1481 startstop = ide_dma_timeout_retry(drive, wait);
1482 } else
1483 startstop =
1484 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG));
1485 }
1486 drive->service_time = jiffies - drive->service_start;
1487 spin_lock_irq(&ide_lock);
1488 enable_irq(hwif->irq);
1489 if (startstop == ide_stopped)
1490 hwgroup->busy = 0;
1491 }
1492 }
1493 ide_do_request(hwgroup, IDE_NO_IRQ);
1494 spin_unlock_irqrestore(&ide_lock, flags);
1495}
1496
1497/**
1498 * unexpected_intr - handle an unexpected IDE interrupt
1499 * @irq: interrupt line
1500 * @hwgroup: hwgroup being processed
1501 *
1502 * There's nothing really useful we can do with an unexpected interrupt,
1503 * other than reading the status register (to clear it), and logging it.
1504 * There should be no way that an irq can happen before we're ready for it,
1505 * so we needn't worry much about losing an "important" interrupt here.
1506 *
1507 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1508 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1509 * looks "good", we just ignore the interrupt completely.
1510 *
1511 * This routine assumes __cli() is in effect when called.
1512 *
1513 * If an unexpected interrupt happens on irq15 while we are handling irq14
1514 * and if the two interfaces are "serialized" (CMD640), then it looks like
1515 * we could screw up by interfering with a new request being set up for
1516 * irq15.
1517 *
1518 * In reality, this is a non-issue. The new command is not sent unless
1519 * the drive is ready to accept one, in which case we know the drive is
1520 * not trying to interrupt us. And ide_set_handler() is always invoked
1521 * before completing the issuance of any new drive command, so we will not
1522 * be accidentally invoked as a result of any valid command completion
1523 * interrupt.
1524 *
1525 * Note that we must walk the entire hwgroup here. We know which hwif
1526 * is doing the current command, but we don't know which hwif burped
1527 * mysteriously.
1528 */
1529
1530static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1531{
1532 u8 stat;
1533 ide_hwif_t *hwif = hwgroup->hwif;
1534
1535 /*
1536 * handle the unexpected interrupt
1537 */
1538 do {
1539 if (hwif->irq == irq) {
1540 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1541 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1542 /* Try to not flood the console with msgs */
1543 static unsigned long last_msgtime, count;
1544 ++count;
1545 if (time_after(jiffies, last_msgtime + HZ)) {
1546 last_msgtime = jiffies;
1547 printk(KERN_ERR "%s%s: unexpected interrupt, "
1548 "status=0x%02x, count=%ld\n",
1549 hwif->name,
1550 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1551 }
1552 }
1553 }
1554 } while ((hwif = hwif->next) != hwgroup->hwif);
1555}
1556
1557/**
1558 * ide_intr - default IDE interrupt handler
1559 * @irq: interrupt number
1560 * @dev_id: hwif group
1561 * @regs: unused weirdness from the kernel irq layer
1562 *
1563 * This is the default IRQ handler for the IDE layer. You should
1564 * not need to override it. If you do be aware it is subtle in
1565 * places
1566 *
1567 * hwgroup->hwif is the interface in the group currently performing
1568 * a command. hwgroup->drive is the drive and hwgroup->handler is
1569 * the IRQ handler to call. As we issue a command the handlers
1570 * step through multiple states, reassigning the handler to the
1571 * next step in the process. Unlike a smart SCSI controller IDE
1572 * expects the main processor to sequence the various transfer
1573 * stages. We also manage a poll timer to catch up with most
1574 * timeout situations. There are still a few where the handlers
1575 * don't ever decide to give up.
1576 *
1577 * The handler eventually returns ide_stopped to indicate the
1578 * request completed. At this point we issue the next request
1579 * on the hwgroup and the process begins again.
1580 */
1581
David Howells7d12e782006-10-05 14:55:46 +01001582irqreturn_t ide_intr (int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001583{
1584 unsigned long flags;
1585 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1586 ide_hwif_t *hwif;
1587 ide_drive_t *drive;
1588 ide_handler_t *handler;
1589 ide_startstop_t startstop;
1590
1591 spin_lock_irqsave(&ide_lock, flags);
1592 hwif = hwgroup->hwif;
1593
1594 if (!ide_ack_intr(hwif)) {
1595 spin_unlock_irqrestore(&ide_lock, flags);
1596 return IRQ_NONE;
1597 }
1598
1599 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1600 /*
1601 * Not expecting an interrupt from this drive.
1602 * That means this could be:
1603 * (1) an interrupt from another PCI device
1604 * sharing the same PCI INT# as us.
1605 * or (2) a drive just entered sleep or standby mode,
1606 * and is interrupting to let us know.
1607 * or (3) a spurious interrupt of unknown origin.
1608 *
1609 * For PCI, we cannot tell the difference,
1610 * so in that case we just ignore it and hope it goes away.
1611 *
1612 * FIXME: unexpected_intr should be hwif-> then we can
1613 * remove all the ifdef PCI crap
1614 */
1615#ifdef CONFIG_BLK_DEV_IDEPCI
1616 if (hwif->pci_dev && !hwif->pci_dev->vendor)
1617#endif /* CONFIG_BLK_DEV_IDEPCI */
1618 {
1619 /*
1620 * Probably not a shared PCI interrupt,
1621 * so we can safely try to do something about it:
1622 */
1623 unexpected_intr(irq, hwgroup);
1624#ifdef CONFIG_BLK_DEV_IDEPCI
1625 } else {
1626 /*
1627 * Whack the status register, just in case
1628 * we have a leftover pending IRQ.
1629 */
1630 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1631#endif /* CONFIG_BLK_DEV_IDEPCI */
1632 }
1633 spin_unlock_irqrestore(&ide_lock, flags);
1634 return IRQ_NONE;
1635 }
1636 drive = hwgroup->drive;
1637 if (!drive) {
1638 /*
1639 * This should NEVER happen, and there isn't much
1640 * we could do about it here.
1641 *
1642 * [Note - this can occur if the drive is hot unplugged]
1643 */
1644 spin_unlock_irqrestore(&ide_lock, flags);
1645 return IRQ_HANDLED;
1646 }
1647 if (!drive_is_ready(drive)) {
1648 /*
1649 * This happens regularly when we share a PCI IRQ with
1650 * another device. Unfortunately, it can also happen
1651 * with some buggy drives that trigger the IRQ before
1652 * their status register is up to date. Hopefully we have
1653 * enough advance overhead that the latter isn't a problem.
1654 */
1655 spin_unlock_irqrestore(&ide_lock, flags);
1656 return IRQ_NONE;
1657 }
1658 if (!hwgroup->busy) {
1659 hwgroup->busy = 1; /* paranoia */
1660 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1661 }
1662 hwgroup->handler = NULL;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001663 hwgroup->req_gen++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001664 del_timer(&hwgroup->timer);
1665 spin_unlock(&ide_lock);
1666
Albert Leef0dd8712007-02-17 02:40:21 +01001667 /* Some controllers might set DMA INTR no matter DMA or PIO;
1668 * bmdma status might need to be cleared even for
1669 * PIO interrupts to prevent spurious/lost irq.
1670 */
1671 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma))
1672 /* ide_dma_end() needs bmdma status for error checking.
1673 * So, skip clearing bmdma status here and leave it
1674 * to ide_dma_end() if this is dma interrupt.
1675 */
1676 hwif->ide_dma_clear_irq(drive);
1677
Linus Torvalds1da177e2005-04-16 15:20:36 -07001678 if (drive->unmask)
Ingo Molnar366c7f52006-07-03 00:25:25 -07001679 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001680 /* service this interrupt, may set handler for next interrupt */
1681 startstop = handler(drive);
1682 spin_lock_irq(&ide_lock);
1683
1684 /*
1685 * Note that handler() may have set things up for another
1686 * interrupt to occur soon, but it cannot happen until
1687 * we exit from this routine, because it will be the
1688 * same irq as is currently being serviced here, and Linux
1689 * won't allow another of the same (on any CPU) until we return.
1690 */
1691 drive->service_time = jiffies - drive->service_start;
1692 if (startstop == ide_stopped) {
1693 if (hwgroup->handler == NULL) { /* paranoia */
1694 hwgroup->busy = 0;
1695 ide_do_request(hwgroup, hwif->irq);
1696 } else {
1697 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1698 "on exit\n", drive->name);
1699 }
1700 }
1701 spin_unlock_irqrestore(&ide_lock, flags);
1702 return IRQ_HANDLED;
1703}
1704
1705/**
1706 * ide_init_drive_cmd - initialize a drive command request
1707 * @rq: request object
1708 *
1709 * Initialize a request before we fill it in and send it down to
1710 * ide_do_drive_cmd. Commands must be set up by this function. Right
1711 * now it doesn't do a lot, but if that changes abusers will have a
Andreas Mohrd6e05ed2006-06-26 18:35:02 +02001712 * nasty surprise.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001713 */
1714
1715void ide_init_drive_cmd (struct request *rq)
1716{
1717 memset(rq, 0, sizeof(*rq));
Jens Axboe4aff5e22006-08-10 08:44:47 +02001718 rq->cmd_type = REQ_TYPE_ATA_CMD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001719 rq->ref_count = 1;
1720}
1721
1722EXPORT_SYMBOL(ide_init_drive_cmd);
1723
1724/**
1725 * ide_do_drive_cmd - issue IDE special command
1726 * @drive: device to issue command
1727 * @rq: request to issue
1728 * @action: action for processing
1729 *
1730 * This function issues a special IDE device request
1731 * onto the request queue.
1732 *
1733 * If action is ide_wait, then the rq is queued at the end of the
1734 * request queue, and the function sleeps until it has been processed.
1735 * This is for use when invoked from an ioctl handler.
1736 *
1737 * If action is ide_preempt, then the rq is queued at the head of
1738 * the request queue, displacing the currently-being-processed
1739 * request and this function returns immediately without waiting
1740 * for the new rq to be completed. This is VERY DANGEROUS, and is
1741 * intended for careful use by the ATAPI tape/cdrom driver code.
1742 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001743 * If action is ide_end, then the rq is queued at the end of the
1744 * request queue, and the function returns immediately without waiting
1745 * for the new rq to be completed. This is again intended for careful
1746 * use by the ATAPI tape/cdrom driver code.
1747 */
1748
1749int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1750{
1751 unsigned long flags;
1752 ide_hwgroup_t *hwgroup = HWGROUP(drive);
Ingo Molnar60be6b92006-07-03 00:25:26 -07001753 DECLARE_COMPLETION_ONSTACK(wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754 int where = ELEVATOR_INSERT_BACK, err;
1755 int must_wait = (action == ide_wait || action == ide_head_wait);
1756
1757 rq->errors = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001758
1759 /*
1760 * we need to hold an extra reference to request for safe inspection
1761 * after completion
1762 */
1763 if (must_wait) {
1764 rq->ref_count++;
Jens Axboec00895a2006-09-30 20:29:12 +02001765 rq->end_io_data = &wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001766 rq->end_io = blk_end_sync_rq;
1767 }
1768
1769 spin_lock_irqsave(&ide_lock, flags);
1770 if (action == ide_preempt)
1771 hwgroup->rq = NULL;
1772 if (action == ide_preempt || action == ide_head_wait) {
1773 where = ELEVATOR_INSERT_FRONT;
Jens Axboe4aff5e22006-08-10 08:44:47 +02001774 rq->cmd_flags |= REQ_PREEMPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001775 }
1776 __elv_add_request(drive->queue, rq, where, 0);
1777 ide_do_request(hwgroup, IDE_NO_IRQ);
1778 spin_unlock_irqrestore(&ide_lock, flags);
1779
1780 err = 0;
1781 if (must_wait) {
1782 wait_for_completion(&wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001783 if (rq->errors)
1784 err = -EIO;
1785
1786 blk_put_request(rq);
1787 }
1788
1789 return err;
1790}
1791
1792EXPORT_SYMBOL(ide_do_drive_cmd);