blob: 32eaa3f8051592f4ecb132ccaa08fb8ced966d60 [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>
Jiri Slaby1977f032007-10-18 23:40:25 -070050#include <linux/bitops.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
52#include <asm/byteorder.h>
53#include <asm/irq.h>
54#include <asm/uaccess.h>
55#include <asm/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
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) */
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200204 ide_set_max_pio(drive);
Bartlomiej Zolnierkiewicz317a46a2007-05-10 00:01:11 +0200205 /*
206 * skip idedisk_pm_idle for ATAPI devices
207 */
208 if (drive->media != ide_disk)
209 pm->pm_step = ide_pm_restore_dma;
210 else
211 ide_complete_power_step(drive, rq, 0, 0);
Jason Lunz8c2c0112006-10-03 01:14:26 -0700212 return ide_stopped;
213
214 case idedisk_pm_idle: /* Resume step 2 (idle) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_IDLEIMMEDIATE;
216 args->command_type = IDE_DRIVE_TASK_NO_DATA;
217 args->handler = task_no_data_intr;
218 return do_rw_taskfile(drive, args);
219
Jason Lunz8c2c0112006-10-03 01:14:26 -0700220 case ide_pm_restore_dma: /* Resume step 3 (restore DMA) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 /*
Bartlomiej Zolnierkiewicz0ae2e172007-10-16 22:29:55 +0200222 * Right now, all we do is call ide_set_dma(drive),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 * we could be smarter and check for current xfer_speed
224 * in struct drive etc...
225 */
Bartlomiej Zolnierkiewicz0ae2e172007-10-16 22:29:55 +0200226 if (drive->hwif->ide_dma_on == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 break;
Bartlomiej Zolnierkiewicz793a9722007-05-16 00:51:43 +0200228 drive->hwif->dma_off_quietly(drive);
Bartlomiej Zolnierkiewicz8987d212007-07-20 01:11:56 +0200229 /*
230 * TODO: respect ->using_dma setting
231 */
Bartlomiej Zolnierkiewicz3608b5d2007-02-17 02:40:26 +0100232 ide_set_dma(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233 break;
234 }
Jens Axboead3cadd2006-06-13 08:46:57 +0200235 pm->pm_step = ide_pm_state_completed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 return ide_stopped;
237}
238
239/**
Alan Coxdbe217a2006-06-25 05:47:44 -0700240 * ide_end_dequeued_request - complete an IDE I/O
241 * @drive: IDE device for the I/O
242 * @uptodate:
243 * @nr_sectors: number of sectors completed
244 *
245 * Complete an I/O that is no longer on the request queue. This
246 * typically occurs when we pull the request and issue a REQUEST_SENSE.
247 * We must still finish the old request but we must not tamper with the
248 * queue in the meantime.
249 *
250 * NOTE: This path does not handle barrier, but barrier is not supported
251 * on ide-cd anyway.
252 */
253
254int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
255 int uptodate, int nr_sectors)
256{
257 unsigned long flags;
258 int ret = 1;
259
260 spin_lock_irqsave(&ide_lock, flags);
261
Jens Axboe4aff5e22006-08-10 08:44:47 +0200262 BUG_ON(!blk_rq_started(rq));
Alan Coxdbe217a2006-06-25 05:47:44 -0700263
264 /*
265 * if failfast is set on a request, override number of sectors and
266 * complete the whole request right now
267 */
268 if (blk_noretry_request(rq) && end_io_error(uptodate))
269 nr_sectors = rq->hard_nr_sectors;
270
271 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
272 rq->errors = -EIO;
273
274 /*
275 * decide whether to reenable DMA -- 3 is a random magic for now,
276 * if we DMA timeout more than 3 times, just stay in PIO
277 */
278 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
279 drive->state = 0;
280 HWGROUP(drive)->hwif->ide_dma_on(drive);
281 }
282
283 if (!end_that_request_first(rq, uptodate, nr_sectors)) {
284 add_disk_randomness(rq->rq_disk);
285 if (blk_rq_tagged(rq))
286 blk_queue_end_tag(drive->queue, rq);
287 end_that_request_last(rq, uptodate);
288 ret = 0;
289 }
290 spin_unlock_irqrestore(&ide_lock, flags);
291 return ret;
292}
293EXPORT_SYMBOL_GPL(ide_end_dequeued_request);
294
295
296/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297 * ide_complete_pm_request - end the current Power Management request
298 * @drive: target drive
299 * @rq: request
300 *
301 * This function cleans up the current PM request and stops the queue
302 * if necessary.
303 */
304static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
305{
306 unsigned long flags;
307
308#ifdef DEBUG_PM
309 printk("%s: completing PM request, %s\n", drive->name,
310 blk_pm_suspend_request(rq) ? "suspend" : "resume");
311#endif
312 spin_lock_irqsave(&ide_lock, flags);
313 if (blk_pm_suspend_request(rq)) {
314 blk_stop_queue(drive->queue);
315 } else {
316 drive->blocked = 0;
317 blk_start_queue(drive->queue);
318 }
319 blkdev_dequeue_request(rq);
320 HWGROUP(drive)->rq = NULL;
Tejun Heo8ffdc652006-01-06 09:49:03 +0100321 end_that_request_last(rq, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 spin_unlock_irqrestore(&ide_lock, flags);
323}
324
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325/**
326 * ide_end_drive_cmd - end an explicit drive command
327 * @drive: command
328 * @stat: status bits
329 * @err: error bits
330 *
331 * Clean up after success/failure of an explicit drive command.
332 * These get thrown onto the queue so they are synchronized with
333 * real I/O operations on the drive.
334 *
335 * In LBA48 mode we have to read the register set twice to get
336 * all the extra information out.
337 */
338
339void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
340{
341 ide_hwif_t *hwif = HWIF(drive);
342 unsigned long flags;
343 struct request *rq;
344
345 spin_lock_irqsave(&ide_lock, flags);
346 rq = HWGROUP(drive)->rq;
347 spin_unlock_irqrestore(&ide_lock, flags);
348
Jens Axboe4aff5e22006-08-10 08:44:47 +0200349 if (rq->cmd_type == REQ_TYPE_ATA_CMD) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 u8 *args = (u8 *) rq->buffer;
351 if (rq->errors == 0)
352 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
353
354 if (args) {
355 args[0] = stat;
356 args[1] = err;
357 args[2] = hwif->INB(IDE_NSECTOR_REG);
358 }
Jens Axboe4aff5e22006-08-10 08:44:47 +0200359 } else if (rq->cmd_type == REQ_TYPE_ATA_TASK) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 u8 *args = (u8 *) rq->buffer;
361 if (rq->errors == 0)
362 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
363
364 if (args) {
365 args[0] = stat;
366 args[1] = err;
367 args[2] = hwif->INB(IDE_NSECTOR_REG);
368 args[3] = hwif->INB(IDE_SECTOR_REG);
369 args[4] = hwif->INB(IDE_LCYL_REG);
370 args[5] = hwif->INB(IDE_HCYL_REG);
371 args[6] = hwif->INB(IDE_SELECT_REG);
372 }
Jens Axboe4aff5e22006-08-10 08:44:47 +0200373 } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 ide_task_t *args = (ide_task_t *) rq->special;
375 if (rq->errors == 0)
376 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
377
378 if (args) {
379 if (args->tf_in_flags.b.data) {
380 u16 data = hwif->INW(IDE_DATA_REG);
381 args->tfRegister[IDE_DATA_OFFSET] = (data) & 0xFF;
382 args->hobRegister[IDE_DATA_OFFSET] = (data >> 8) & 0xFF;
383 }
384 args->tfRegister[IDE_ERROR_OFFSET] = err;
385 /* be sure we're looking at the low order bits */
386 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG);
387 args->tfRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
388 args->tfRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
389 args->tfRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
390 args->tfRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
391 args->tfRegister[IDE_SELECT_OFFSET] = hwif->INB(IDE_SELECT_REG);
392 args->tfRegister[IDE_STATUS_OFFSET] = stat;
393
394 if (drive->addressing == 1) {
395 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
396 args->hobRegister[IDE_FEATURE_OFFSET] = hwif->INB(IDE_FEATURE_REG);
397 args->hobRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
398 args->hobRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
399 args->hobRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
400 args->hobRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
401 }
402 }
403 } else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200404 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405#ifdef DEBUG_PM
406 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
407 drive->name, rq->pm->pm_step, stat, err);
408#endif
409 ide_complete_power_step(drive, rq, stat, err);
Jens Axboead3cadd2006-06-13 08:46:57 +0200410 if (pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 ide_complete_pm_request(drive, rq);
412 return;
413 }
414
415 spin_lock_irqsave(&ide_lock, flags);
416 blkdev_dequeue_request(rq);
417 HWGROUP(drive)->rq = NULL;
418 rq->errors = err;
Tejun Heo8ffdc652006-01-06 09:49:03 +0100419 end_that_request_last(rq, !rq->errors);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 spin_unlock_irqrestore(&ide_lock, flags);
421}
422
423EXPORT_SYMBOL(ide_end_drive_cmd);
424
425/**
426 * try_to_flush_leftover_data - flush junk
427 * @drive: drive to flush
428 *
429 * try_to_flush_leftover_data() is invoked in response to a drive
430 * unexpectedly having its DRQ_STAT bit set. As an alternative to
431 * resetting the drive, this routine tries to clear the condition
432 * by read a sector's worth of data from the drive. Of course,
433 * this may not help if the drive is *waiting* for data from *us*.
434 */
435static void try_to_flush_leftover_data (ide_drive_t *drive)
436{
437 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;
438
439 if (drive->media != ide_disk)
440 return;
441 while (i > 0) {
442 u32 buffer[16];
443 u32 wcount = (i > 16) ? 16 : i;
444
445 i -= wcount;
446 HWIF(drive)->ata_input_data(drive, buffer, wcount);
447 }
448}
449
450static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
451{
452 if (rq->rq_disk) {
453 ide_driver_t *drv;
454
455 drv = *(ide_driver_t **)rq->rq_disk->private_data;
456 drv->end_request(drive, 0, 0);
457 } else
458 ide_end_request(drive, 0, 0);
459}
460
461static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
462{
463 ide_hwif_t *hwif = drive->hwif;
464
465 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
466 /* other bits are useless when BUSY */
467 rq->errors |= ERROR_RESET;
468 } else if (stat & ERR_STAT) {
469 /* err has different meaning on cdrom and tape */
470 if (err == ABRT_ERR) {
471 if (drive->select.b.lba &&
472 /* some newer drives don't support WIN_SPECIFY */
473 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
474 return ide_stopped;
475 } else if ((err & BAD_CRC) == BAD_CRC) {
476 /* UDMA crc error, just retry the operation */
477 drive->crc_count++;
478 } else if (err & (BBD_ERR | ECC_ERR)) {
479 /* retries won't help these */
480 rq->errors = ERROR_MAX;
481 } else if (err & TRK0_ERR) {
482 /* help it find track zero */
483 rq->errors |= ERROR_RECAL;
484 }
485 }
486
Bartlomiej Zolnierkiewiczed67b922007-10-19 00:30:10 +0200487 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ &&
488 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 try_to_flush_leftover_data(drive);
490
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200491 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 ide_kill_rq(drive, rq);
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200493 return ide_stopped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494 }
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200495
496 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
497 rq->errors |= ERROR_RESET;
498
499 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
500 ++rq->errors;
501 return ide_do_reset(drive);
502 }
503
504 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
505 drive->special.b.recalibrate = 1;
506
507 ++rq->errors;
508
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509 return ide_stopped;
510}
511
512static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
513{
514 ide_hwif_t *hwif = drive->hwif;
515
516 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
517 /* other bits are useless when BUSY */
518 rq->errors |= ERROR_RESET;
519 } else {
520 /* add decoding error stuff */
521 }
522
523 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
524 /* force an abort */
525 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
526
527 if (rq->errors >= ERROR_MAX) {
528 ide_kill_rq(drive, rq);
529 } else {
530 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
531 ++rq->errors;
532 return ide_do_reset(drive);
533 }
534 ++rq->errors;
535 }
536
537 return ide_stopped;
538}
539
540ide_startstop_t
541__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
542{
543 if (drive->media == ide_disk)
544 return ide_ata_error(drive, rq, stat, err);
545 return ide_atapi_error(drive, rq, stat, err);
546}
547
548EXPORT_SYMBOL_GPL(__ide_error);
549
550/**
551 * ide_error - handle an error on the IDE
552 * @drive: drive the error occurred on
553 * @msg: message to report
554 * @stat: status bits
555 *
556 * ide_error() takes action based on the error returned by the drive.
557 * For normal I/O that may well include retries. We deal with
558 * both new-style (taskfile) and old style command handling here.
559 * In the case of taskfile command handling there is work left to
560 * do
561 */
562
563ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
564{
565 struct request *rq;
566 u8 err;
567
568 err = ide_dump_status(drive, msg, stat);
569
570 if ((rq = HWGROUP(drive)->rq) == NULL)
571 return ide_stopped;
572
573 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200574 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575 rq->errors = 1;
576 ide_end_drive_cmd(drive, stat, err);
577 return ide_stopped;
578 }
579
580 if (rq->rq_disk) {
581 ide_driver_t *drv;
582
583 drv = *(ide_driver_t **)rq->rq_disk->private_data;
584 return drv->error(drive, rq, stat, err);
585 } else
586 return __ide_error(drive, rq, stat, err);
587}
588
589EXPORT_SYMBOL_GPL(ide_error);
590
591ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
592{
593 if (drive->media != ide_disk)
594 rq->errors |= ERROR_RESET;
595
596 ide_kill_rq(drive, rq);
597
598 return ide_stopped;
599}
600
601EXPORT_SYMBOL_GPL(__ide_abort);
602
603/**
Adrian Bunk338cec32005-09-10 00:26:54 -0700604 * ide_abort - abort pending IDE operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 * @drive: drive the error occurred on
606 * @msg: message to report
607 *
608 * ide_abort kills and cleans up when we are about to do a
609 * host initiated reset on active commands. Longer term we
610 * want handlers to have sensible abort handling themselves
611 *
612 * This differs fundamentally from ide_error because in
613 * this case the command is doing just fine when we
614 * blow it away.
615 */
616
617ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
618{
619 struct request *rq;
620
621 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
622 return ide_stopped;
623
624 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200625 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626 rq->errors = 1;
627 ide_end_drive_cmd(drive, BUSY_STAT, 0);
628 return ide_stopped;
629 }
630
631 if (rq->rq_disk) {
632 ide_driver_t *drv;
633
634 drv = *(ide_driver_t **)rq->rq_disk->private_data;
635 return drv->abort(drive, rq);
636 } else
637 return __ide_abort(drive, rq);
638}
639
640/**
641 * ide_cmd - issue a simple drive command
642 * @drive: drive the command is for
643 * @cmd: command byte
644 * @nsect: sector byte
645 * @handler: handler for the command completion
646 *
647 * Issue a simple drive command with interrupts.
648 * The drive must be selected beforehand.
649 */
650
651static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect,
652 ide_handler_t *handler)
653{
654 ide_hwif_t *hwif = HWIF(drive);
655 if (IDE_CONTROL_REG)
656 hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */
657 SELECT_MASK(drive,0);
658 hwif->OUTB(nsect,IDE_NSECTOR_REG);
659 ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL);
660}
661
662/**
663 * drive_cmd_intr - drive command completion interrupt
664 * @drive: drive the completion interrupt occurred on
665 *
666 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
Adrian Bunk338cec32005-09-10 00:26:54 -0700667 * We do any necessary data reading and then wait for the drive to
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 * go non busy. At that point we may read the error data and complete
669 * the request
670 */
671
672static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
673{
674 struct request *rq = HWGROUP(drive)->rq;
675 ide_hwif_t *hwif = HWIF(drive);
676 u8 *args = (u8 *) rq->buffer;
677 u8 stat = hwif->INB(IDE_STATUS_REG);
678 int retries = 10;
679
Ingo Molnar366c7f52006-07-03 00:25:25 -0700680 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681 if ((stat & DRQ_STAT) && args && args[3]) {
682 u8 io_32bit = drive->io_32bit;
683 drive->io_32bit = 0;
684 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
685 drive->io_32bit = io_32bit;
686 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
687 udelay(100);
688 }
689
690 if (!OK_STAT(stat, READY_STAT, BAD_STAT))
691 return ide_error(drive, "drive_cmd", stat);
692 /* calls ide_end_drive_cmd */
693 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
694 return ide_stopped;
695}
696
697static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task)
698{
699 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
700 task->tfRegister[IDE_SECTOR_OFFSET] = drive->sect;
701 task->tfRegister[IDE_LCYL_OFFSET] = drive->cyl;
702 task->tfRegister[IDE_HCYL_OFFSET] = drive->cyl>>8;
703 task->tfRegister[IDE_SELECT_OFFSET] = ((drive->head-1)|drive->select.all)&0xBF;
704 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY;
705
706 task->handler = &set_geometry_intr;
707}
708
709static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task)
710{
711 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
712 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE;
713
714 task->handler = &recal_intr;
715}
716
717static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task)
718{
719 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req;
720 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT;
721
722 task->handler = &set_multmode_intr;
723}
724
725static ide_startstop_t ide_disk_special(ide_drive_t *drive)
726{
727 special_t *s = &drive->special;
728 ide_task_t args;
729
730 memset(&args, 0, sizeof(ide_task_t));
731 args.command_type = IDE_DRIVE_TASK_NO_DATA;
732
733 if (s->b.set_geometry) {
734 s->b.set_geometry = 0;
735 ide_init_specify_cmd(drive, &args);
736 } else if (s->b.recalibrate) {
737 s->b.recalibrate = 0;
738 ide_init_restore_cmd(drive, &args);
739 } else if (s->b.set_multmode) {
740 s->b.set_multmode = 0;
741 if (drive->mult_req > drive->id->max_multsect)
742 drive->mult_req = drive->id->max_multsect;
743 ide_init_setmult_cmd(drive, &args);
744 } else if (s->all) {
745 int special = s->all;
746 s->all = 0;
747 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
748 return ide_stopped;
749 }
750
751 do_rw_taskfile(drive, &args);
752
753 return ide_started;
754}
755
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200756/*
757 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
758 */
759static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio)
760{
761 switch (req_pio) {
762 case 202:
763 case 201:
764 case 200:
765 case 102:
766 case 101:
767 case 100:
768 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0;
769 case 9:
770 case 8:
771 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0;
772 case 7:
773 case 6:
774 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0;
775 default:
776 return 0;
777 }
778}
779
Linus Torvalds1da177e2005-04-16 15:20:36 -0700780/**
781 * do_special - issue some special commands
782 * @drive: drive the command is for
783 *
784 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
785 * commands to a drive. It used to do much more, but has been scaled
786 * back.
787 */
788
789static ide_startstop_t do_special (ide_drive_t *drive)
790{
791 special_t *s = &drive->special;
792
793#ifdef DEBUG
794 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
795#endif
796 if (s->b.set_tune) {
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200797 ide_hwif_t *hwif = drive->hwif;
798 u8 req_pio = drive->tune_req;
799
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 s->b.set_tune = 0;
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200801
802 if (set_pio_mode_abuse(drive->hwif, req_pio)) {
803 if (hwif->set_pio_mode)
804 hwif->set_pio_mode(drive, req_pio);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200805 } else {
806 int keep_dma = drive->using_dma;
807
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200808 ide_set_pio(drive, req_pio);
809
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200810 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) {
811 if (keep_dma)
812 hwif->ide_dma_on(drive);
813 }
814 }
815
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 return ide_stopped;
817 } else {
818 if (drive->media == ide_disk)
819 return ide_disk_special(drive);
820
821 s->all = 0;
822 drive->mult_req = 0;
823 return ide_stopped;
824 }
825}
826
827void ide_map_sg(ide_drive_t *drive, struct request *rq)
828{
829 ide_hwif_t *hwif = drive->hwif;
830 struct scatterlist *sg = hwif->sg_table;
831
832 if (hwif->sg_mapped) /* needed by ide-scsi */
833 return;
834
Jens Axboe4aff5e22006-08-10 08:44:47 +0200835 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
837 } else {
838 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
839 hwif->sg_nents = 1;
840 }
841}
842
843EXPORT_SYMBOL_GPL(ide_map_sg);
844
845void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
846{
847 ide_hwif_t *hwif = drive->hwif;
848
849 hwif->nsect = hwif->nleft = rq->nr_sectors;
Jens Axboe55c16a72007-07-25 08:13:56 +0200850 hwif->cursg_ofs = 0;
851 hwif->cursg = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852}
853
854EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
855
856/**
857 * execute_drive_command - issue special drive command
Adrian Bunk338cec32005-09-10 00:26:54 -0700858 * @drive: the drive to issue the command on
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 * @rq: the request structure holding the command
860 *
861 * execute_drive_cmd() issues a special drive command, usually
862 * initiated by ioctl() from the external hdparm program. The
863 * command can be a drive command, drive task or taskfile
864 * operation. Weirdly you can call it with NULL to wait for
865 * all commands to finish. Don't do this as that is due to change
866 */
867
868static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
869 struct request *rq)
870{
871 ide_hwif_t *hwif = HWIF(drive);
Jens Axboe4aff5e22006-08-10 08:44:47 +0200872 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873 ide_task_t *args = rq->special;
874
875 if (!args)
876 goto done;
877
878 hwif->data_phase = args->data_phase;
879
880 switch (hwif->data_phase) {
881 case TASKFILE_MULTI_OUT:
882 case TASKFILE_OUT:
883 case TASKFILE_MULTI_IN:
884 case TASKFILE_IN:
885 ide_init_sg_cmd(drive, rq);
886 ide_map_sg(drive, rq);
887 default:
888 break;
889 }
890
891 if (args->tf_out_flags.all != 0)
892 return flagged_taskfile(drive, args);
893 return do_rw_taskfile(drive, args);
Jens Axboe4aff5e22006-08-10 08:44:47 +0200894 } else if (rq->cmd_type == REQ_TYPE_ATA_TASK) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 u8 *args = rq->buffer;
896 u8 sel;
897
898 if (!args)
899 goto done;
900#ifdef DEBUG
901 printk("%s: DRIVE_TASK_CMD ", drive->name);
902 printk("cmd=0x%02x ", args[0]);
903 printk("fr=0x%02x ", args[1]);
904 printk("ns=0x%02x ", args[2]);
905 printk("sc=0x%02x ", args[3]);
906 printk("lcyl=0x%02x ", args[4]);
907 printk("hcyl=0x%02x ", args[5]);
908 printk("sel=0x%02x\n", args[6]);
909#endif
910 hwif->OUTB(args[1], IDE_FEATURE_REG);
911 hwif->OUTB(args[3], IDE_SECTOR_REG);
912 hwif->OUTB(args[4], IDE_LCYL_REG);
913 hwif->OUTB(args[5], IDE_HCYL_REG);
914 sel = (args[6] & ~0x10);
915 if (drive->select.b.unit)
916 sel |= 0x10;
917 hwif->OUTB(sel, IDE_SELECT_REG);
918 ide_cmd(drive, args[0], args[2], &drive_cmd_intr);
919 return ide_started;
Jens Axboe4aff5e22006-08-10 08:44:47 +0200920 } else if (rq->cmd_type == REQ_TYPE_ATA_CMD) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 u8 *args = rq->buffer;
922
923 if (!args)
924 goto done;
925#ifdef DEBUG
926 printk("%s: DRIVE_CMD ", drive->name);
927 printk("cmd=0x%02x ", args[0]);
928 printk("sc=0x%02x ", args[1]);
929 printk("fr=0x%02x ", args[2]);
930 printk("xx=0x%02x\n", args[3]);
931#endif
932 if (args[0] == WIN_SMART) {
933 hwif->OUTB(0x4f, IDE_LCYL_REG);
934 hwif->OUTB(0xc2, IDE_HCYL_REG);
935 hwif->OUTB(args[2],IDE_FEATURE_REG);
936 hwif->OUTB(args[1],IDE_SECTOR_REG);
937 ide_cmd(drive, args[0], args[3], &drive_cmd_intr);
938 return ide_started;
939 }
940 hwif->OUTB(args[2],IDE_FEATURE_REG);
941 ide_cmd(drive, args[0], args[1], &drive_cmd_intr);
942 return ide_started;
943 }
944
945done:
946 /*
947 * NULL is actually a valid way of waiting for
948 * all current requests to be flushed from the queue.
949 */
950#ifdef DEBUG
951 printk("%s: DRIVE_CMD (null)\n", drive->name);
952#endif
953 ide_end_drive_cmd(drive,
954 hwif->INB(IDE_STATUS_REG),
955 hwif->INB(IDE_ERROR_REG));
956 return ide_stopped;
957}
958
Jens Axboead3cadd2006-06-13 08:46:57 +0200959static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
960{
Jens Axboec00895a2006-09-30 20:29:12 +0200961 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200962
963 if (blk_pm_suspend_request(rq) &&
964 pm->pm_step == ide_pm_state_start_suspend)
965 /* Mark drive blocked when starting the suspend sequence. */
966 drive->blocked = 1;
967 else if (blk_pm_resume_request(rq) &&
968 pm->pm_step == ide_pm_state_start_resume) {
969 /*
970 * The first thing we do on wakeup is to wait for BSY bit to
971 * go away (with a looong timeout) as a drive on this hwif may
972 * just be POSTing itself.
973 * We do that before even selecting as the "other" device on
974 * the bus may be broken enough to walk on our toes at this
975 * point.
976 */
977 int rc;
978#ifdef DEBUG_PM
979 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
980#endif
981 rc = ide_wait_not_busy(HWIF(drive), 35000);
982 if (rc)
983 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
984 SELECT_DRIVE(drive);
985 HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]);
Al Boldi178184b2006-06-26 00:26:13 -0700986 rc = ide_wait_not_busy(HWIF(drive), 100000);
Jens Axboead3cadd2006-06-13 08:46:57 +0200987 if (rc)
988 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
989 }
990}
991
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992/**
993 * start_request - start of I/O and command issuing for IDE
994 *
995 * start_request() initiates handling of a new I/O request. It
996 * accepts commands and I/O (read/write) requests. It also does
997 * the final remapping for weird stuff like EZDrive. Once
998 * device mapper can work sector level the EZDrive stuff can go away
999 *
1000 * FIXME: this function needs a rename
1001 */
1002
1003static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
1004{
1005 ide_startstop_t startstop;
1006 sector_t block;
1007
Jens Axboe4aff5e22006-08-10 08:44:47 +02001008 BUG_ON(!blk_rq_started(rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009
1010#ifdef DEBUG
1011 printk("%s: start_request: current=0x%08lx\n",
1012 HWIF(drive)->name, (unsigned long) rq);
1013#endif
1014
1015 /* bail early if we've exceeded max_failures */
1016 if (drive->max_failures && (drive->failures > drive->max_failures)) {
1017 goto kill_rq;
1018 }
1019
1020 block = rq->sector;
1021 if (blk_fs_request(rq) &&
1022 (drive->media == ide_disk || drive->media == ide_floppy)) {
1023 block += drive->sect0;
1024 }
1025 /* Yecch - this will shift the entire interval,
1026 possibly killing some innocent following sector */
1027 if (block == 0 && drive->remap_0_to_1 == 1)
1028 block = 1; /* redirect MBR access to EZ-Drive partn table */
1029
Jens Axboead3cadd2006-06-13 08:46:57 +02001030 if (blk_pm_request(rq))
1031 ide_check_pm_state(drive, rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001032
1033 SELECT_DRIVE(drive);
1034 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
1035 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
1036 return startstop;
1037 }
1038 if (!drive->special.all) {
1039 ide_driver_t *drv;
1040
Suleiman Souhlal513daad2007-03-26 23:03:20 +02001041 /*
1042 * We reset the drive so we need to issue a SETFEATURES.
1043 * Do it _after_ do_special() restored device parameters.
1044 */
1045 if (drive->current_speed == 0xff)
1046 ide_config_drive_speed(drive, drive->desired_speed);
1047
Jens Axboe4aff5e22006-08-10 08:44:47 +02001048 if (rq->cmd_type == REQ_TYPE_ATA_CMD ||
1049 rq->cmd_type == REQ_TYPE_ATA_TASK ||
1050 rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 return execute_drive_cmd(drive, rq);
1052 else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +02001053 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054#ifdef DEBUG_PM
1055 printk("%s: start_power_step(step: %d)\n",
1056 drive->name, rq->pm->pm_step);
1057#endif
1058 startstop = ide_start_power_step(drive, rq);
1059 if (startstop == ide_stopped &&
Jens Axboead3cadd2006-06-13 08:46:57 +02001060 pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061 ide_complete_pm_request(drive, rq);
1062 return startstop;
1063 }
1064
1065 drv = *(ide_driver_t **)rq->rq_disk->private_data;
1066 return drv->do_request(drive, rq, block);
1067 }
1068 return do_special(drive);
1069kill_rq:
1070 ide_kill_rq(drive, rq);
1071 return ide_stopped;
1072}
1073
1074/**
1075 * ide_stall_queue - pause an IDE device
1076 * @drive: drive to stall
1077 * @timeout: time to stall for (jiffies)
1078 *
1079 * ide_stall_queue() can be used by a drive to give excess bandwidth back
1080 * to the hwgroup by sleeping for timeout jiffies.
1081 */
1082
1083void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
1084{
1085 if (timeout > WAIT_WORSTCASE)
1086 timeout = WAIT_WORSTCASE;
1087 drive->sleep = timeout + jiffies;
1088 drive->sleeping = 1;
1089}
1090
1091EXPORT_SYMBOL(ide_stall_queue);
1092
1093#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
1094
1095/**
1096 * choose_drive - select a drive to service
1097 * @hwgroup: hardware group to select on
1098 *
1099 * choose_drive() selects the next drive which will be serviced.
1100 * This is necessary because the IDE layer can't issue commands
1101 * to both drives on the same cable, unlike SCSI.
1102 */
1103
1104static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
1105{
1106 ide_drive_t *drive, *best;
1107
1108repeat:
1109 best = NULL;
1110 drive = hwgroup->drive;
1111
1112 /*
1113 * drive is doing pre-flush, ordered write, post-flush sequence. even
1114 * though that is 3 requests, it must be seen as a single transaction.
1115 * we must not preempt this drive until that is complete
1116 */
1117 if (blk_queue_flushing(drive->queue)) {
1118 /*
1119 * small race where queue could get replugged during
1120 * the 3-request flush cycle, just yank the plug since
1121 * we want it to finish asap
1122 */
1123 blk_remove_plug(drive->queue);
1124 return drive;
1125 }
1126
1127 do {
1128 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
1129 && !elv_queue_empty(drive->queue)) {
1130 if (!best
1131 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
1132 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
1133 {
1134 if (!blk_queue_plugged(drive->queue))
1135 best = drive;
1136 }
1137 }
1138 } while ((drive = drive->next) != hwgroup->drive);
1139 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1140 long t = (signed long)(WAKEUP(best) - jiffies);
1141 if (t >= WAIT_MIN_SLEEP) {
1142 /*
1143 * We *may* have some time to spare, but first let's see if
1144 * someone can potentially benefit from our nice mood today..
1145 */
1146 drive = best->next;
1147 do {
1148 if (!drive->sleeping
1149 && time_before(jiffies - best->service_time, WAKEUP(drive))
1150 && time_before(WAKEUP(drive), jiffies + t))
1151 {
1152 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1153 goto repeat;
1154 }
1155 } while ((drive = drive->next) != best);
1156 }
1157 }
1158 return best;
1159}
1160
1161/*
1162 * Issue a new request to a drive from hwgroup
1163 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1164 *
1165 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1166 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1167 * may have both interfaces in a single hwgroup to "serialize" access.
1168 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1169 * together into one hwgroup for serialized access.
1170 *
1171 * Note also that several hwgroups can end up sharing a single IRQ,
1172 * possibly along with many other devices. This is especially common in
1173 * PCI-based systems with off-board IDE controller cards.
1174 *
1175 * The IDE driver uses the single global ide_lock spinlock to protect
1176 * access to the request queues, and to protect the hwgroup->busy flag.
1177 *
1178 * The first thread into the driver for a particular hwgroup sets the
1179 * hwgroup->busy flag to indicate that this hwgroup is now active,
1180 * and then initiates processing of the top request from the request queue.
1181 *
1182 * Other threads attempting entry notice the busy setting, and will simply
1183 * queue their new requests and exit immediately. Note that hwgroup->busy
1184 * remains set even when the driver is merely awaiting the next interrupt.
1185 * Thus, the meaning is "this hwgroup is busy processing a request".
1186 *
1187 * When processing of a request completes, the completing thread or IRQ-handler
1188 * will start the next request from the queue. If no more work remains,
1189 * the driver will clear the hwgroup->busy flag and exit.
1190 *
1191 * The ide_lock (spinlock) is used to protect all access to the
1192 * hwgroup->busy flag, but is otherwise not needed for most processing in
1193 * the driver. This makes the driver much more friendlier to shared IRQs
1194 * than previous designs, while remaining 100% (?) SMP safe and capable.
1195 */
1196static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1197{
1198 ide_drive_t *drive;
1199 ide_hwif_t *hwif;
1200 struct request *rq;
1201 ide_startstop_t startstop;
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001202 int loops = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001203
1204 /* for atari only: POSSIBLY BROKEN HERE(?) */
1205 ide_get_lock(ide_intr, hwgroup);
1206
1207 /* caller must own ide_lock */
1208 BUG_ON(!irqs_disabled());
1209
1210 while (!hwgroup->busy) {
1211 hwgroup->busy = 1;
1212 drive = choose_drive(hwgroup);
1213 if (drive == NULL) {
1214 int sleeping = 0;
1215 unsigned long sleep = 0; /* shut up, gcc */
1216 hwgroup->rq = NULL;
1217 drive = hwgroup->drive;
1218 do {
1219 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1220 sleeping = 1;
1221 sleep = drive->sleep;
1222 }
1223 } while ((drive = drive->next) != hwgroup->drive);
1224 if (sleeping) {
1225 /*
1226 * Take a short snooze, and then wake up this hwgroup again.
1227 * This gives other hwgroups on the same a chance to
1228 * play fairly with us, just in case there are big differences
1229 * in relative throughputs.. don't want to hog the cpu too much.
1230 */
1231 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1232 sleep = jiffies + WAIT_MIN_SLEEP;
1233#if 1
1234 if (timer_pending(&hwgroup->timer))
1235 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1236#endif
1237 /* so that ide_timer_expiry knows what to do */
1238 hwgroup->sleeping = 1;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001239 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001240 mod_timer(&hwgroup->timer, sleep);
1241 /* we purposely leave hwgroup->busy==1
1242 * while sleeping */
1243 } else {
1244 /* Ugly, but how can we sleep for the lock
1245 * otherwise? perhaps from tq_disk?
1246 */
1247
1248 /* for atari only */
1249 ide_release_lock();
1250 hwgroup->busy = 0;
1251 }
1252
1253 /* no more work for this hwgroup (for now) */
1254 return;
1255 }
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001256 again:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001257 hwif = HWIF(drive);
1258 if (hwgroup->hwif->sharing_irq &&
1259 hwif != hwgroup->hwif &&
1260 hwif->io_ports[IDE_CONTROL_OFFSET]) {
1261 /* set nIEN for previous hwif */
1262 SELECT_INTERRUPT(drive);
1263 }
1264 hwgroup->hwif = hwif;
1265 hwgroup->drive = drive;
1266 drive->sleeping = 0;
1267 drive->service_start = jiffies;
1268
1269 if (blk_queue_plugged(drive->queue)) {
1270 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1271 break;
1272 }
1273
1274 /*
1275 * we know that the queue isn't empty, but this can happen
1276 * if the q->prep_rq_fn() decides to kill a request
1277 */
1278 rq = elv_next_request(drive->queue);
1279 if (!rq) {
1280 hwgroup->busy = 0;
1281 break;
1282 }
1283
1284 /*
1285 * Sanity: don't accept a request that isn't a PM request
1286 * if we are currently power managed. This is very important as
1287 * blk_stop_queue() doesn't prevent the elv_next_request()
1288 * above to return us whatever is in the queue. Since we call
1289 * ide_do_request() ourselves, we end up taking requests while
1290 * the queue is blocked...
1291 *
1292 * We let requests forced at head of queue with ide-preempt
1293 * though. I hope that doesn't happen too much, hopefully not
1294 * unless the subdriver triggers such a thing in its own PM
1295 * state machine.
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001296 *
1297 * We count how many times we loop here to make sure we service
1298 * all drives in the hwgroup without looping for ever
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 */
Jens Axboe4aff5e22006-08-10 08:44:47 +02001300 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) {
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001301 drive = drive->next ? drive->next : hwgroup->drive;
1302 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1303 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304 /* We clear busy, there should be no pending ATA command at this point. */
1305 hwgroup->busy = 0;
1306 break;
1307 }
1308
1309 hwgroup->rq = rq;
1310
1311 /*
1312 * Some systems have trouble with IDE IRQs arriving while
1313 * the driver is still setting things up. So, here we disable
1314 * the IRQ used by this interface while the request is being started.
1315 * This may look bad at first, but pretty much the same thing
1316 * happens anyway when any interrupt comes in, IDE or otherwise
1317 * -- the kernel masks the IRQ while it is being handled.
1318 */
1319 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1320 disable_irq_nosync(hwif->irq);
1321 spin_unlock(&ide_lock);
Ingo Molnar366c7f52006-07-03 00:25:25 -07001322 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 /* allow other IRQs while we start this request */
1324 startstop = start_request(drive, rq);
1325 spin_lock_irq(&ide_lock);
1326 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1327 enable_irq(hwif->irq);
1328 if (startstop == ide_stopped)
1329 hwgroup->busy = 0;
1330 }
1331}
1332
1333/*
1334 * Passes the stuff to ide_do_request
1335 */
Jens Axboe165125e2007-07-24 09:28:11 +02001336void do_ide_request(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337{
1338 ide_drive_t *drive = q->queuedata;
1339
1340 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1341}
1342
1343/*
1344 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1345 * retry the current request in pio mode instead of risking tossing it
1346 * all away
1347 */
1348static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1349{
1350 ide_hwif_t *hwif = HWIF(drive);
1351 struct request *rq;
1352 ide_startstop_t ret = ide_stopped;
1353
1354 /*
1355 * end current dma transaction
1356 */
1357
1358 if (error < 0) {
1359 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1360 (void)HWIF(drive)->ide_dma_end(drive);
1361 ret = ide_error(drive, "dma timeout error",
1362 hwif->INB(IDE_STATUS_REG));
1363 } else {
1364 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
Sergei Shtylyovc283f5d2007-07-09 23:17:54 +02001365 hwif->dma_timeout(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001366 }
1367
1368 /*
1369 * disable dma for now, but remember that we did so because of
1370 * a timeout -- we'll reenable after we finish this next request
1371 * (or rather the first chunk of it) in pio.
1372 */
1373 drive->retry_pio++;
1374 drive->state = DMA_PIO_RETRY;
Bartlomiej Zolnierkiewicz7469aaf2007-02-17 02:40:26 +01001375 hwif->dma_off_quietly(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001376
1377 /*
1378 * un-busy drive etc (hwgroup->busy is cleared on return) and
1379 * make sure request is sane
1380 */
1381 rq = HWGROUP(drive)->rq;
Hua Zhongce42f192006-10-03 01:14:15 -07001382
1383 if (!rq)
1384 goto out;
1385
Linus Torvalds1da177e2005-04-16 15:20:36 -07001386 HWGROUP(drive)->rq = NULL;
1387
1388 rq->errors = 0;
1389
1390 if (!rq->bio)
1391 goto out;
1392
1393 rq->sector = rq->bio->bi_sector;
1394 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1395 rq->hard_cur_sectors = rq->current_nr_sectors;
1396 rq->buffer = bio_data(rq->bio);
1397out:
1398 return ret;
1399}
1400
1401/**
1402 * ide_timer_expiry - handle lack of an IDE interrupt
1403 * @data: timer callback magic (hwgroup)
1404 *
1405 * An IDE command has timed out before the expected drive return
1406 * occurred. At this point we attempt to clean up the current
1407 * mess. If the current handler includes an expiry handler then
1408 * we invoke the expiry handler, and providing it is happy the
1409 * work is done. If that fails we apply generic recovery rules
1410 * invoking the handler and checking the drive DMA status. We
1411 * have an excessively incestuous relationship with the DMA
1412 * logic that wants cleaning up.
1413 */
1414
1415void ide_timer_expiry (unsigned long data)
1416{
1417 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1418 ide_handler_t *handler;
1419 ide_expiry_t *expiry;
1420 unsigned long flags;
1421 unsigned long wait = -1;
1422
1423 spin_lock_irqsave(&ide_lock, flags);
1424
Suleiman Souhlal23450312007-04-10 22:38:37 +02001425 if (((handler = hwgroup->handler) == NULL) ||
1426 (hwgroup->req_gen != hwgroup->req_gen_timer)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001427 /*
1428 * Either a marginal timeout occurred
1429 * (got the interrupt just as timer expired),
1430 * or we were "sleeping" to give other devices a chance.
1431 * Either way, we don't really want to complain about anything.
1432 */
1433 if (hwgroup->sleeping) {
1434 hwgroup->sleeping = 0;
1435 hwgroup->busy = 0;
1436 }
1437 } else {
1438 ide_drive_t *drive = hwgroup->drive;
1439 if (!drive) {
1440 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1441 hwgroup->handler = NULL;
1442 } else {
1443 ide_hwif_t *hwif;
1444 ide_startstop_t startstop = ide_stopped;
1445 if (!hwgroup->busy) {
1446 hwgroup->busy = 1; /* paranoia */
1447 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1448 }
1449 if ((expiry = hwgroup->expiry) != NULL) {
1450 /* continue */
1451 if ((wait = expiry(drive)) > 0) {
1452 /* reset timer */
1453 hwgroup->timer.expires = jiffies + wait;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001454 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001455 add_timer(&hwgroup->timer);
1456 spin_unlock_irqrestore(&ide_lock, flags);
1457 return;
1458 }
1459 }
1460 hwgroup->handler = NULL;
1461 /*
1462 * We need to simulate a real interrupt when invoking
1463 * the handler() function, which means we need to
1464 * globally mask the specific IRQ:
1465 */
1466 spin_unlock(&ide_lock);
1467 hwif = HWIF(drive);
1468#if DISABLE_IRQ_NOSYNC
1469 disable_irq_nosync(hwif->irq);
1470#else
1471 /* disable_irq_nosync ?? */
1472 disable_irq(hwif->irq);
1473#endif /* DISABLE_IRQ_NOSYNC */
1474 /* local CPU only,
1475 * as if we were handling an interrupt */
1476 local_irq_disable();
1477 if (hwgroup->polling) {
1478 startstop = handler(drive);
1479 } else if (drive_is_ready(drive)) {
1480 if (drive->waiting_for_dma)
Sergei Shtylyov841d2a92007-07-09 23:17:54 +02001481 hwgroup->hwif->dma_lost_irq(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482 (void)ide_ack_intr(hwif);
1483 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1484 startstop = handler(drive);
1485 } else {
1486 if (drive->waiting_for_dma) {
1487 startstop = ide_dma_timeout_retry(drive, wait);
1488 } else
1489 startstop =
1490 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG));
1491 }
1492 drive->service_time = jiffies - drive->service_start;
1493 spin_lock_irq(&ide_lock);
1494 enable_irq(hwif->irq);
1495 if (startstop == ide_stopped)
1496 hwgroup->busy = 0;
1497 }
1498 }
1499 ide_do_request(hwgroup, IDE_NO_IRQ);
1500 spin_unlock_irqrestore(&ide_lock, flags);
1501}
1502
1503/**
1504 * unexpected_intr - handle an unexpected IDE interrupt
1505 * @irq: interrupt line
1506 * @hwgroup: hwgroup being processed
1507 *
1508 * There's nothing really useful we can do with an unexpected interrupt,
1509 * other than reading the status register (to clear it), and logging it.
1510 * There should be no way that an irq can happen before we're ready for it,
1511 * so we needn't worry much about losing an "important" interrupt here.
1512 *
1513 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1514 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1515 * looks "good", we just ignore the interrupt completely.
1516 *
1517 * This routine assumes __cli() is in effect when called.
1518 *
1519 * If an unexpected interrupt happens on irq15 while we are handling irq14
1520 * and if the two interfaces are "serialized" (CMD640), then it looks like
1521 * we could screw up by interfering with a new request being set up for
1522 * irq15.
1523 *
1524 * In reality, this is a non-issue. The new command is not sent unless
1525 * the drive is ready to accept one, in which case we know the drive is
1526 * not trying to interrupt us. And ide_set_handler() is always invoked
1527 * before completing the issuance of any new drive command, so we will not
1528 * be accidentally invoked as a result of any valid command completion
1529 * interrupt.
1530 *
1531 * Note that we must walk the entire hwgroup here. We know which hwif
1532 * is doing the current command, but we don't know which hwif burped
1533 * mysteriously.
1534 */
1535
1536static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1537{
1538 u8 stat;
1539 ide_hwif_t *hwif = hwgroup->hwif;
1540
1541 /*
1542 * handle the unexpected interrupt
1543 */
1544 do {
1545 if (hwif->irq == irq) {
1546 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1547 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1548 /* Try to not flood the console with msgs */
1549 static unsigned long last_msgtime, count;
1550 ++count;
1551 if (time_after(jiffies, last_msgtime + HZ)) {
1552 last_msgtime = jiffies;
1553 printk(KERN_ERR "%s%s: unexpected interrupt, "
1554 "status=0x%02x, count=%ld\n",
1555 hwif->name,
1556 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1557 }
1558 }
1559 }
1560 } while ((hwif = hwif->next) != hwgroup->hwif);
1561}
1562
1563/**
1564 * ide_intr - default IDE interrupt handler
1565 * @irq: interrupt number
1566 * @dev_id: hwif group
1567 * @regs: unused weirdness from the kernel irq layer
1568 *
1569 * This is the default IRQ handler for the IDE layer. You should
1570 * not need to override it. If you do be aware it is subtle in
1571 * places
1572 *
1573 * hwgroup->hwif is the interface in the group currently performing
1574 * a command. hwgroup->drive is the drive and hwgroup->handler is
1575 * the IRQ handler to call. As we issue a command the handlers
1576 * step through multiple states, reassigning the handler to the
1577 * next step in the process. Unlike a smart SCSI controller IDE
1578 * expects the main processor to sequence the various transfer
1579 * stages. We also manage a poll timer to catch up with most
1580 * timeout situations. There are still a few where the handlers
1581 * don't ever decide to give up.
1582 *
1583 * The handler eventually returns ide_stopped to indicate the
1584 * request completed. At this point we issue the next request
1585 * on the hwgroup and the process begins again.
1586 */
1587
David Howells7d12e782006-10-05 14:55:46 +01001588irqreturn_t ide_intr (int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001589{
1590 unsigned long flags;
1591 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1592 ide_hwif_t *hwif;
1593 ide_drive_t *drive;
1594 ide_handler_t *handler;
1595 ide_startstop_t startstop;
1596
1597 spin_lock_irqsave(&ide_lock, flags);
1598 hwif = hwgroup->hwif;
1599
1600 if (!ide_ack_intr(hwif)) {
1601 spin_unlock_irqrestore(&ide_lock, flags);
1602 return IRQ_NONE;
1603 }
1604
1605 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1606 /*
1607 * Not expecting an interrupt from this drive.
1608 * That means this could be:
1609 * (1) an interrupt from another PCI device
1610 * sharing the same PCI INT# as us.
1611 * or (2) a drive just entered sleep or standby mode,
1612 * and is interrupting to let us know.
1613 * or (3) a spurious interrupt of unknown origin.
1614 *
1615 * For PCI, we cannot tell the difference,
1616 * so in that case we just ignore it and hope it goes away.
1617 *
1618 * FIXME: unexpected_intr should be hwif-> then we can
1619 * remove all the ifdef PCI crap
1620 */
1621#ifdef CONFIG_BLK_DEV_IDEPCI
1622 if (hwif->pci_dev && !hwif->pci_dev->vendor)
1623#endif /* CONFIG_BLK_DEV_IDEPCI */
1624 {
1625 /*
1626 * Probably not a shared PCI interrupt,
1627 * so we can safely try to do something about it:
1628 */
1629 unexpected_intr(irq, hwgroup);
1630#ifdef CONFIG_BLK_DEV_IDEPCI
1631 } else {
1632 /*
1633 * Whack the status register, just in case
1634 * we have a leftover pending IRQ.
1635 */
1636 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1637#endif /* CONFIG_BLK_DEV_IDEPCI */
1638 }
1639 spin_unlock_irqrestore(&ide_lock, flags);
1640 return IRQ_NONE;
1641 }
1642 drive = hwgroup->drive;
1643 if (!drive) {
1644 /*
1645 * This should NEVER happen, and there isn't much
1646 * we could do about it here.
1647 *
1648 * [Note - this can occur if the drive is hot unplugged]
1649 */
1650 spin_unlock_irqrestore(&ide_lock, flags);
1651 return IRQ_HANDLED;
1652 }
1653 if (!drive_is_ready(drive)) {
1654 /*
1655 * This happens regularly when we share a PCI IRQ with
1656 * another device. Unfortunately, it can also happen
1657 * with some buggy drives that trigger the IRQ before
1658 * their status register is up to date. Hopefully we have
1659 * enough advance overhead that the latter isn't a problem.
1660 */
1661 spin_unlock_irqrestore(&ide_lock, flags);
1662 return IRQ_NONE;
1663 }
1664 if (!hwgroup->busy) {
1665 hwgroup->busy = 1; /* paranoia */
1666 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1667 }
1668 hwgroup->handler = NULL;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001669 hwgroup->req_gen++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001670 del_timer(&hwgroup->timer);
1671 spin_unlock(&ide_lock);
1672
Albert Leef0dd8712007-02-17 02:40:21 +01001673 /* Some controllers might set DMA INTR no matter DMA or PIO;
1674 * bmdma status might need to be cleared even for
1675 * PIO interrupts to prevent spurious/lost irq.
1676 */
1677 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma))
1678 /* ide_dma_end() needs bmdma status for error checking.
1679 * So, skip clearing bmdma status here and leave it
1680 * to ide_dma_end() if this is dma interrupt.
1681 */
1682 hwif->ide_dma_clear_irq(drive);
1683
Linus Torvalds1da177e2005-04-16 15:20:36 -07001684 if (drive->unmask)
Ingo Molnar366c7f52006-07-03 00:25:25 -07001685 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001686 /* service this interrupt, may set handler for next interrupt */
1687 startstop = handler(drive);
1688 spin_lock_irq(&ide_lock);
1689
1690 /*
1691 * Note that handler() may have set things up for another
1692 * interrupt to occur soon, but it cannot happen until
1693 * we exit from this routine, because it will be the
1694 * same irq as is currently being serviced here, and Linux
1695 * won't allow another of the same (on any CPU) until we return.
1696 */
1697 drive->service_time = jiffies - drive->service_start;
1698 if (startstop == ide_stopped) {
1699 if (hwgroup->handler == NULL) { /* paranoia */
1700 hwgroup->busy = 0;
1701 ide_do_request(hwgroup, hwif->irq);
1702 } else {
1703 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1704 "on exit\n", drive->name);
1705 }
1706 }
1707 spin_unlock_irqrestore(&ide_lock, flags);
1708 return IRQ_HANDLED;
1709}
1710
1711/**
1712 * ide_init_drive_cmd - initialize a drive command request
1713 * @rq: request object
1714 *
1715 * Initialize a request before we fill it in and send it down to
1716 * ide_do_drive_cmd. Commands must be set up by this function. Right
1717 * now it doesn't do a lot, but if that changes abusers will have a
Andreas Mohrd6e05ed2006-06-26 18:35:02 +02001718 * nasty surprise.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001719 */
1720
1721void ide_init_drive_cmd (struct request *rq)
1722{
1723 memset(rq, 0, sizeof(*rq));
Jens Axboe4aff5e22006-08-10 08:44:47 +02001724 rq->cmd_type = REQ_TYPE_ATA_CMD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001725 rq->ref_count = 1;
1726}
1727
1728EXPORT_SYMBOL(ide_init_drive_cmd);
1729
1730/**
1731 * ide_do_drive_cmd - issue IDE special command
1732 * @drive: device to issue command
1733 * @rq: request to issue
1734 * @action: action for processing
1735 *
1736 * This function issues a special IDE device request
1737 * onto the request queue.
1738 *
1739 * If action is ide_wait, then the rq is queued at the end of the
1740 * request queue, and the function sleeps until it has been processed.
1741 * This is for use when invoked from an ioctl handler.
1742 *
1743 * If action is ide_preempt, then the rq is queued at the head of
1744 * the request queue, displacing the currently-being-processed
1745 * request and this function returns immediately without waiting
1746 * for the new rq to be completed. This is VERY DANGEROUS, and is
1747 * intended for careful use by the ATAPI tape/cdrom driver code.
1748 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001749 * If action is ide_end, then the rq is queued at the end of the
1750 * request queue, and the function returns immediately without waiting
1751 * for the new rq to be completed. This is again intended for careful
1752 * use by the ATAPI tape/cdrom driver code.
1753 */
1754
1755int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1756{
1757 unsigned long flags;
1758 ide_hwgroup_t *hwgroup = HWGROUP(drive);
Ingo Molnar60be6b92006-07-03 00:25:26 -07001759 DECLARE_COMPLETION_ONSTACK(wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001760 int where = ELEVATOR_INSERT_BACK, err;
1761 int must_wait = (action == ide_wait || action == ide_head_wait);
1762
1763 rq->errors = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001764
1765 /*
1766 * we need to hold an extra reference to request for safe inspection
1767 * after completion
1768 */
1769 if (must_wait) {
1770 rq->ref_count++;
Jens Axboec00895a2006-09-30 20:29:12 +02001771 rq->end_io_data = &wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001772 rq->end_io = blk_end_sync_rq;
1773 }
1774
1775 spin_lock_irqsave(&ide_lock, flags);
1776 if (action == ide_preempt)
1777 hwgroup->rq = NULL;
1778 if (action == ide_preempt || action == ide_head_wait) {
1779 where = ELEVATOR_INSERT_FRONT;
Jens Axboe4aff5e22006-08-10 08:44:47 +02001780 rq->cmd_flags |= REQ_PREEMPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001781 }
1782 __elv_add_request(drive->queue, rq, where, 0);
1783 ide_do_request(hwgroup, IDE_NO_IRQ);
1784 spin_unlock_irqrestore(&ide_lock, flags);
1785
1786 err = 0;
1787 if (must_wait) {
1788 wait_for_completion(&wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001789 if (rq->errors)
1790 err = -EIO;
1791
1792 blk_put_request(rq);
1793 }
1794
1795 return err;
1796}
1797
1798EXPORT_SYMBOL(ide_do_drive_cmd);