blob: 04273d3c147c09ecead03f5e9315740a530d1d03 [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) */
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 /*
222 * Right now, all we do is call hwif->ide_dma_check(drive),
223 * we could be smarter and check for current xfer_speed
224 * in struct drive etc...
225 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 if (drive->hwif->ide_dma_check == NULL)
227 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
Alan Coxda574af2006-06-28 04:27:01 -0700487 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ && hwif->err_stops_fifo == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488 try_to_flush_leftover_data(drive);
489
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200490 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 ide_kill_rq(drive, rq);
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200492 return ide_stopped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 }
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200494
495 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
496 rq->errors |= ERROR_RESET;
497
498 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
499 ++rq->errors;
500 return ide_do_reset(drive);
501 }
502
503 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
504 drive->special.b.recalibrate = 1;
505
506 ++rq->errors;
507
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 return ide_stopped;
509}
510
511static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
512{
513 ide_hwif_t *hwif = drive->hwif;
514
515 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
516 /* other bits are useless when BUSY */
517 rq->errors |= ERROR_RESET;
518 } else {
519 /* add decoding error stuff */
520 }
521
522 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
523 /* force an abort */
524 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
525
526 if (rq->errors >= ERROR_MAX) {
527 ide_kill_rq(drive, rq);
528 } else {
529 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
530 ++rq->errors;
531 return ide_do_reset(drive);
532 }
533 ++rq->errors;
534 }
535
536 return ide_stopped;
537}
538
539ide_startstop_t
540__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
541{
542 if (drive->media == ide_disk)
543 return ide_ata_error(drive, rq, stat, err);
544 return ide_atapi_error(drive, rq, stat, err);
545}
546
547EXPORT_SYMBOL_GPL(__ide_error);
548
549/**
550 * ide_error - handle an error on the IDE
551 * @drive: drive the error occurred on
552 * @msg: message to report
553 * @stat: status bits
554 *
555 * ide_error() takes action based on the error returned by the drive.
556 * For normal I/O that may well include retries. We deal with
557 * both new-style (taskfile) and old style command handling here.
558 * In the case of taskfile command handling there is work left to
559 * do
560 */
561
562ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
563{
564 struct request *rq;
565 u8 err;
566
567 err = ide_dump_status(drive, msg, stat);
568
569 if ((rq = HWGROUP(drive)->rq) == NULL)
570 return ide_stopped;
571
572 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200573 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 rq->errors = 1;
575 ide_end_drive_cmd(drive, stat, err);
576 return ide_stopped;
577 }
578
579 if (rq->rq_disk) {
580 ide_driver_t *drv;
581
582 drv = *(ide_driver_t **)rq->rq_disk->private_data;
583 return drv->error(drive, rq, stat, err);
584 } else
585 return __ide_error(drive, rq, stat, err);
586}
587
588EXPORT_SYMBOL_GPL(ide_error);
589
590ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
591{
592 if (drive->media != ide_disk)
593 rq->errors |= ERROR_RESET;
594
595 ide_kill_rq(drive, rq);
596
597 return ide_stopped;
598}
599
600EXPORT_SYMBOL_GPL(__ide_abort);
601
602/**
Adrian Bunk338cec32005-09-10 00:26:54 -0700603 * ide_abort - abort pending IDE operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 * @drive: drive the error occurred on
605 * @msg: message to report
606 *
607 * ide_abort kills and cleans up when we are about to do a
608 * host initiated reset on active commands. Longer term we
609 * want handlers to have sensible abort handling themselves
610 *
611 * This differs fundamentally from ide_error because in
612 * this case the command is doing just fine when we
613 * blow it away.
614 */
615
616ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
617{
618 struct request *rq;
619
620 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
621 return ide_stopped;
622
623 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200624 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 rq->errors = 1;
626 ide_end_drive_cmd(drive, BUSY_STAT, 0);
627 return ide_stopped;
628 }
629
630 if (rq->rq_disk) {
631 ide_driver_t *drv;
632
633 drv = *(ide_driver_t **)rq->rq_disk->private_data;
634 return drv->abort(drive, rq);
635 } else
636 return __ide_abort(drive, rq);
637}
638
639/**
640 * ide_cmd - issue a simple drive command
641 * @drive: drive the command is for
642 * @cmd: command byte
643 * @nsect: sector byte
644 * @handler: handler for the command completion
645 *
646 * Issue a simple drive command with interrupts.
647 * The drive must be selected beforehand.
648 */
649
650static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect,
651 ide_handler_t *handler)
652{
653 ide_hwif_t *hwif = HWIF(drive);
654 if (IDE_CONTROL_REG)
655 hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */
656 SELECT_MASK(drive,0);
657 hwif->OUTB(nsect,IDE_NSECTOR_REG);
658 ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL);
659}
660
661/**
662 * drive_cmd_intr - drive command completion interrupt
663 * @drive: drive the completion interrupt occurred on
664 *
665 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
Adrian Bunk338cec32005-09-10 00:26:54 -0700666 * We do any necessary data reading and then wait for the drive to
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 * go non busy. At that point we may read the error data and complete
668 * the request
669 */
670
671static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
672{
673 struct request *rq = HWGROUP(drive)->rq;
674 ide_hwif_t *hwif = HWIF(drive);
675 u8 *args = (u8 *) rq->buffer;
676 u8 stat = hwif->INB(IDE_STATUS_REG);
677 int retries = 10;
678
Ingo Molnar366c7f52006-07-03 00:25:25 -0700679 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 if ((stat & DRQ_STAT) && args && args[3]) {
681 u8 io_32bit = drive->io_32bit;
682 drive->io_32bit = 0;
683 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
684 drive->io_32bit = io_32bit;
685 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
686 udelay(100);
687 }
688
689 if (!OK_STAT(stat, READY_STAT, BAD_STAT))
690 return ide_error(drive, "drive_cmd", stat);
691 /* calls ide_end_drive_cmd */
692 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
693 return ide_stopped;
694}
695
696static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task)
697{
698 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
699 task->tfRegister[IDE_SECTOR_OFFSET] = drive->sect;
700 task->tfRegister[IDE_LCYL_OFFSET] = drive->cyl;
701 task->tfRegister[IDE_HCYL_OFFSET] = drive->cyl>>8;
702 task->tfRegister[IDE_SELECT_OFFSET] = ((drive->head-1)|drive->select.all)&0xBF;
703 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY;
704
705 task->handler = &set_geometry_intr;
706}
707
708static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task)
709{
710 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
711 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE;
712
713 task->handler = &recal_intr;
714}
715
716static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task)
717{
718 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req;
719 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT;
720
721 task->handler = &set_multmode_intr;
722}
723
724static ide_startstop_t ide_disk_special(ide_drive_t *drive)
725{
726 special_t *s = &drive->special;
727 ide_task_t args;
728
729 memset(&args, 0, sizeof(ide_task_t));
730 args.command_type = IDE_DRIVE_TASK_NO_DATA;
731
732 if (s->b.set_geometry) {
733 s->b.set_geometry = 0;
734 ide_init_specify_cmd(drive, &args);
735 } else if (s->b.recalibrate) {
736 s->b.recalibrate = 0;
737 ide_init_restore_cmd(drive, &args);
738 } else if (s->b.set_multmode) {
739 s->b.set_multmode = 0;
740 if (drive->mult_req > drive->id->max_multsect)
741 drive->mult_req = drive->id->max_multsect;
742 ide_init_setmult_cmd(drive, &args);
743 } else if (s->all) {
744 int special = s->all;
745 s->all = 0;
746 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
747 return ide_stopped;
748 }
749
750 do_rw_taskfile(drive, &args);
751
752 return ide_started;
753}
754
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200755/*
756 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
757 */
758static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio)
759{
760 switch (req_pio) {
761 case 202:
762 case 201:
763 case 200:
764 case 102:
765 case 101:
766 case 100:
767 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0;
768 case 9:
769 case 8:
770 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0;
771 case 7:
772 case 6:
773 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0;
774 default:
775 return 0;
776 }
777}
778
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779/**
780 * do_special - issue some special commands
781 * @drive: drive the command is for
782 *
783 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
784 * commands to a drive. It used to do much more, but has been scaled
785 * back.
786 */
787
788static ide_startstop_t do_special (ide_drive_t *drive)
789{
790 special_t *s = &drive->special;
791
792#ifdef DEBUG
793 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
794#endif
795 if (s->b.set_tune) {
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200796 ide_hwif_t *hwif = drive->hwif;
797 u8 req_pio = drive->tune_req;
798
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799 s->b.set_tune = 0;
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200800
801 if (set_pio_mode_abuse(drive->hwif, req_pio)) {
802 if (hwif->set_pio_mode)
803 hwif->set_pio_mode(drive, req_pio);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200804 } else {
805 int keep_dma = drive->using_dma;
806
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200807 ide_set_pio(drive, req_pio);
808
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200809 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) {
810 if (keep_dma)
811 hwif->ide_dma_on(drive);
812 }
813 }
814
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815 return ide_stopped;
816 } else {
817 if (drive->media == ide_disk)
818 return ide_disk_special(drive);
819
820 s->all = 0;
821 drive->mult_req = 0;
822 return ide_stopped;
823 }
824}
825
826void ide_map_sg(ide_drive_t *drive, struct request *rq)
827{
828 ide_hwif_t *hwif = drive->hwif;
829 struct scatterlist *sg = hwif->sg_table;
830
831 if (hwif->sg_mapped) /* needed by ide-scsi */
832 return;
833
Jens Axboe4aff5e22006-08-10 08:44:47 +0200834 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
836 } else {
837 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
838 hwif->sg_nents = 1;
839 }
840}
841
842EXPORT_SYMBOL_GPL(ide_map_sg);
843
844void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
845{
846 ide_hwif_t *hwif = drive->hwif;
847
848 hwif->nsect = hwif->nleft = rq->nr_sectors;
Jens Axboe55c16a72007-07-25 08:13:56 +0200849 hwif->cursg_ofs = 0;
850 hwif->cursg = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851}
852
853EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
854
855/**
856 * execute_drive_command - issue special drive command
Adrian Bunk338cec32005-09-10 00:26:54 -0700857 * @drive: the drive to issue the command on
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858 * @rq: the request structure holding the command
859 *
860 * execute_drive_cmd() issues a special drive command, usually
861 * initiated by ioctl() from the external hdparm program. The
862 * command can be a drive command, drive task or taskfile
863 * operation. Weirdly you can call it with NULL to wait for
864 * all commands to finish. Don't do this as that is due to change
865 */
866
867static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
868 struct request *rq)
869{
870 ide_hwif_t *hwif = HWIF(drive);
Jens Axboe4aff5e22006-08-10 08:44:47 +0200871 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872 ide_task_t *args = rq->special;
873
874 if (!args)
875 goto done;
876
877 hwif->data_phase = args->data_phase;
878
879 switch (hwif->data_phase) {
880 case TASKFILE_MULTI_OUT:
881 case TASKFILE_OUT:
882 case TASKFILE_MULTI_IN:
883 case TASKFILE_IN:
884 ide_init_sg_cmd(drive, rq);
885 ide_map_sg(drive, rq);
886 default:
887 break;
888 }
889
890 if (args->tf_out_flags.all != 0)
891 return flagged_taskfile(drive, args);
892 return do_rw_taskfile(drive, args);
Jens Axboe4aff5e22006-08-10 08:44:47 +0200893 } else if (rq->cmd_type == REQ_TYPE_ATA_TASK) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894 u8 *args = rq->buffer;
895 u8 sel;
896
897 if (!args)
898 goto done;
899#ifdef DEBUG
900 printk("%s: DRIVE_TASK_CMD ", drive->name);
901 printk("cmd=0x%02x ", args[0]);
902 printk("fr=0x%02x ", args[1]);
903 printk("ns=0x%02x ", args[2]);
904 printk("sc=0x%02x ", args[3]);
905 printk("lcyl=0x%02x ", args[4]);
906 printk("hcyl=0x%02x ", args[5]);
907 printk("sel=0x%02x\n", args[6]);
908#endif
909 hwif->OUTB(args[1], IDE_FEATURE_REG);
910 hwif->OUTB(args[3], IDE_SECTOR_REG);
911 hwif->OUTB(args[4], IDE_LCYL_REG);
912 hwif->OUTB(args[5], IDE_HCYL_REG);
913 sel = (args[6] & ~0x10);
914 if (drive->select.b.unit)
915 sel |= 0x10;
916 hwif->OUTB(sel, IDE_SELECT_REG);
917 ide_cmd(drive, args[0], args[2], &drive_cmd_intr);
918 return ide_started;
Jens Axboe4aff5e22006-08-10 08:44:47 +0200919 } else if (rq->cmd_type == REQ_TYPE_ATA_CMD) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 u8 *args = rq->buffer;
921
922 if (!args)
923 goto done;
924#ifdef DEBUG
925 printk("%s: DRIVE_CMD ", drive->name);
926 printk("cmd=0x%02x ", args[0]);
927 printk("sc=0x%02x ", args[1]);
928 printk("fr=0x%02x ", args[2]);
929 printk("xx=0x%02x\n", args[3]);
930#endif
931 if (args[0] == WIN_SMART) {
932 hwif->OUTB(0x4f, IDE_LCYL_REG);
933 hwif->OUTB(0xc2, IDE_HCYL_REG);
934 hwif->OUTB(args[2],IDE_FEATURE_REG);
935 hwif->OUTB(args[1],IDE_SECTOR_REG);
936 ide_cmd(drive, args[0], args[3], &drive_cmd_intr);
937 return ide_started;
938 }
939 hwif->OUTB(args[2],IDE_FEATURE_REG);
940 ide_cmd(drive, args[0], args[1], &drive_cmd_intr);
941 return ide_started;
942 }
943
944done:
945 /*
946 * NULL is actually a valid way of waiting for
947 * all current requests to be flushed from the queue.
948 */
949#ifdef DEBUG
950 printk("%s: DRIVE_CMD (null)\n", drive->name);
951#endif
952 ide_end_drive_cmd(drive,
953 hwif->INB(IDE_STATUS_REG),
954 hwif->INB(IDE_ERROR_REG));
955 return ide_stopped;
956}
957
Jens Axboead3cadd2006-06-13 08:46:57 +0200958static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
959{
Jens Axboec00895a2006-09-30 20:29:12 +0200960 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200961
962 if (blk_pm_suspend_request(rq) &&
963 pm->pm_step == ide_pm_state_start_suspend)
964 /* Mark drive blocked when starting the suspend sequence. */
965 drive->blocked = 1;
966 else if (blk_pm_resume_request(rq) &&
967 pm->pm_step == ide_pm_state_start_resume) {
968 /*
969 * The first thing we do on wakeup is to wait for BSY bit to
970 * go away (with a looong timeout) as a drive on this hwif may
971 * just be POSTing itself.
972 * We do that before even selecting as the "other" device on
973 * the bus may be broken enough to walk on our toes at this
974 * point.
975 */
976 int rc;
977#ifdef DEBUG_PM
978 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
979#endif
980 rc = ide_wait_not_busy(HWIF(drive), 35000);
981 if (rc)
982 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
983 SELECT_DRIVE(drive);
984 HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]);
Al Boldi178184b2006-06-26 00:26:13 -0700985 rc = ide_wait_not_busy(HWIF(drive), 100000);
Jens Axboead3cadd2006-06-13 08:46:57 +0200986 if (rc)
987 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
988 }
989}
990
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991/**
992 * start_request - start of I/O and command issuing for IDE
993 *
994 * start_request() initiates handling of a new I/O request. It
995 * accepts commands and I/O (read/write) requests. It also does
996 * the final remapping for weird stuff like EZDrive. Once
997 * device mapper can work sector level the EZDrive stuff can go away
998 *
999 * FIXME: this function needs a rename
1000 */
1001
1002static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
1003{
1004 ide_startstop_t startstop;
1005 sector_t block;
1006
Jens Axboe4aff5e22006-08-10 08:44:47 +02001007 BUG_ON(!blk_rq_started(rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008
1009#ifdef DEBUG
1010 printk("%s: start_request: current=0x%08lx\n",
1011 HWIF(drive)->name, (unsigned long) rq);
1012#endif
1013
1014 /* bail early if we've exceeded max_failures */
1015 if (drive->max_failures && (drive->failures > drive->max_failures)) {
1016 goto kill_rq;
1017 }
1018
1019 block = rq->sector;
1020 if (blk_fs_request(rq) &&
1021 (drive->media == ide_disk || drive->media == ide_floppy)) {
1022 block += drive->sect0;
1023 }
1024 /* Yecch - this will shift the entire interval,
1025 possibly killing some innocent following sector */
1026 if (block == 0 && drive->remap_0_to_1 == 1)
1027 block = 1; /* redirect MBR access to EZ-Drive partn table */
1028
Jens Axboead3cadd2006-06-13 08:46:57 +02001029 if (blk_pm_request(rq))
1030 ide_check_pm_state(drive, rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001031
1032 SELECT_DRIVE(drive);
1033 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
1034 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
1035 return startstop;
1036 }
1037 if (!drive->special.all) {
1038 ide_driver_t *drv;
1039
Suleiman Souhlal513daad2007-03-26 23:03:20 +02001040 /*
1041 * We reset the drive so we need to issue a SETFEATURES.
1042 * Do it _after_ do_special() restored device parameters.
1043 */
1044 if (drive->current_speed == 0xff)
1045 ide_config_drive_speed(drive, drive->desired_speed);
1046
Jens Axboe4aff5e22006-08-10 08:44:47 +02001047 if (rq->cmd_type == REQ_TYPE_ATA_CMD ||
1048 rq->cmd_type == REQ_TYPE_ATA_TASK ||
1049 rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001050 return execute_drive_cmd(drive, rq);
1051 else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +02001052 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053#ifdef DEBUG_PM
1054 printk("%s: start_power_step(step: %d)\n",
1055 drive->name, rq->pm->pm_step);
1056#endif
1057 startstop = ide_start_power_step(drive, rq);
1058 if (startstop == ide_stopped &&
Jens Axboead3cadd2006-06-13 08:46:57 +02001059 pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060 ide_complete_pm_request(drive, rq);
1061 return startstop;
1062 }
1063
1064 drv = *(ide_driver_t **)rq->rq_disk->private_data;
1065 return drv->do_request(drive, rq, block);
1066 }
1067 return do_special(drive);
1068kill_rq:
1069 ide_kill_rq(drive, rq);
1070 return ide_stopped;
1071}
1072
1073/**
1074 * ide_stall_queue - pause an IDE device
1075 * @drive: drive to stall
1076 * @timeout: time to stall for (jiffies)
1077 *
1078 * ide_stall_queue() can be used by a drive to give excess bandwidth back
1079 * to the hwgroup by sleeping for timeout jiffies.
1080 */
1081
1082void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
1083{
1084 if (timeout > WAIT_WORSTCASE)
1085 timeout = WAIT_WORSTCASE;
1086 drive->sleep = timeout + jiffies;
1087 drive->sleeping = 1;
1088}
1089
1090EXPORT_SYMBOL(ide_stall_queue);
1091
1092#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
1093
1094/**
1095 * choose_drive - select a drive to service
1096 * @hwgroup: hardware group to select on
1097 *
1098 * choose_drive() selects the next drive which will be serviced.
1099 * This is necessary because the IDE layer can't issue commands
1100 * to both drives on the same cable, unlike SCSI.
1101 */
1102
1103static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
1104{
1105 ide_drive_t *drive, *best;
1106
1107repeat:
1108 best = NULL;
1109 drive = hwgroup->drive;
1110
1111 /*
1112 * drive is doing pre-flush, ordered write, post-flush sequence. even
1113 * though that is 3 requests, it must be seen as a single transaction.
1114 * we must not preempt this drive until that is complete
1115 */
1116 if (blk_queue_flushing(drive->queue)) {
1117 /*
1118 * small race where queue could get replugged during
1119 * the 3-request flush cycle, just yank the plug since
1120 * we want it to finish asap
1121 */
1122 blk_remove_plug(drive->queue);
1123 return drive;
1124 }
1125
1126 do {
1127 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
1128 && !elv_queue_empty(drive->queue)) {
1129 if (!best
1130 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
1131 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
1132 {
1133 if (!blk_queue_plugged(drive->queue))
1134 best = drive;
1135 }
1136 }
1137 } while ((drive = drive->next) != hwgroup->drive);
1138 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1139 long t = (signed long)(WAKEUP(best) - jiffies);
1140 if (t >= WAIT_MIN_SLEEP) {
1141 /*
1142 * We *may* have some time to spare, but first let's see if
1143 * someone can potentially benefit from our nice mood today..
1144 */
1145 drive = best->next;
1146 do {
1147 if (!drive->sleeping
1148 && time_before(jiffies - best->service_time, WAKEUP(drive))
1149 && time_before(WAKEUP(drive), jiffies + t))
1150 {
1151 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1152 goto repeat;
1153 }
1154 } while ((drive = drive->next) != best);
1155 }
1156 }
1157 return best;
1158}
1159
1160/*
1161 * Issue a new request to a drive from hwgroup
1162 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1163 *
1164 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1165 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1166 * may have both interfaces in a single hwgroup to "serialize" access.
1167 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1168 * together into one hwgroup for serialized access.
1169 *
1170 * Note also that several hwgroups can end up sharing a single IRQ,
1171 * possibly along with many other devices. This is especially common in
1172 * PCI-based systems with off-board IDE controller cards.
1173 *
1174 * The IDE driver uses the single global ide_lock spinlock to protect
1175 * access to the request queues, and to protect the hwgroup->busy flag.
1176 *
1177 * The first thread into the driver for a particular hwgroup sets the
1178 * hwgroup->busy flag to indicate that this hwgroup is now active,
1179 * and then initiates processing of the top request from the request queue.
1180 *
1181 * Other threads attempting entry notice the busy setting, and will simply
1182 * queue their new requests and exit immediately. Note that hwgroup->busy
1183 * remains set even when the driver is merely awaiting the next interrupt.
1184 * Thus, the meaning is "this hwgroup is busy processing a request".
1185 *
1186 * When processing of a request completes, the completing thread or IRQ-handler
1187 * will start the next request from the queue. If no more work remains,
1188 * the driver will clear the hwgroup->busy flag and exit.
1189 *
1190 * The ide_lock (spinlock) is used to protect all access to the
1191 * hwgroup->busy flag, but is otherwise not needed for most processing in
1192 * the driver. This makes the driver much more friendlier to shared IRQs
1193 * than previous designs, while remaining 100% (?) SMP safe and capable.
1194 */
1195static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1196{
1197 ide_drive_t *drive;
1198 ide_hwif_t *hwif;
1199 struct request *rq;
1200 ide_startstop_t startstop;
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001201 int loops = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001202
1203 /* for atari only: POSSIBLY BROKEN HERE(?) */
1204 ide_get_lock(ide_intr, hwgroup);
1205
1206 /* caller must own ide_lock */
1207 BUG_ON(!irqs_disabled());
1208
1209 while (!hwgroup->busy) {
1210 hwgroup->busy = 1;
1211 drive = choose_drive(hwgroup);
1212 if (drive == NULL) {
1213 int sleeping = 0;
1214 unsigned long sleep = 0; /* shut up, gcc */
1215 hwgroup->rq = NULL;
1216 drive = hwgroup->drive;
1217 do {
1218 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1219 sleeping = 1;
1220 sleep = drive->sleep;
1221 }
1222 } while ((drive = drive->next) != hwgroup->drive);
1223 if (sleeping) {
1224 /*
1225 * Take a short snooze, and then wake up this hwgroup again.
1226 * This gives other hwgroups on the same a chance to
1227 * play fairly with us, just in case there are big differences
1228 * in relative throughputs.. don't want to hog the cpu too much.
1229 */
1230 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1231 sleep = jiffies + WAIT_MIN_SLEEP;
1232#if 1
1233 if (timer_pending(&hwgroup->timer))
1234 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1235#endif
1236 /* so that ide_timer_expiry knows what to do */
1237 hwgroup->sleeping = 1;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001238 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001239 mod_timer(&hwgroup->timer, sleep);
1240 /* we purposely leave hwgroup->busy==1
1241 * while sleeping */
1242 } else {
1243 /* Ugly, but how can we sleep for the lock
1244 * otherwise? perhaps from tq_disk?
1245 */
1246
1247 /* for atari only */
1248 ide_release_lock();
1249 hwgroup->busy = 0;
1250 }
1251
1252 /* no more work for this hwgroup (for now) */
1253 return;
1254 }
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001255 again:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256 hwif = HWIF(drive);
1257 if (hwgroup->hwif->sharing_irq &&
1258 hwif != hwgroup->hwif &&
1259 hwif->io_ports[IDE_CONTROL_OFFSET]) {
1260 /* set nIEN for previous hwif */
1261 SELECT_INTERRUPT(drive);
1262 }
1263 hwgroup->hwif = hwif;
1264 hwgroup->drive = drive;
1265 drive->sleeping = 0;
1266 drive->service_start = jiffies;
1267
1268 if (blk_queue_plugged(drive->queue)) {
1269 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1270 break;
1271 }
1272
1273 /*
1274 * we know that the queue isn't empty, but this can happen
1275 * if the q->prep_rq_fn() decides to kill a request
1276 */
1277 rq = elv_next_request(drive->queue);
1278 if (!rq) {
1279 hwgroup->busy = 0;
1280 break;
1281 }
1282
1283 /*
1284 * Sanity: don't accept a request that isn't a PM request
1285 * if we are currently power managed. This is very important as
1286 * blk_stop_queue() doesn't prevent the elv_next_request()
1287 * above to return us whatever is in the queue. Since we call
1288 * ide_do_request() ourselves, we end up taking requests while
1289 * the queue is blocked...
1290 *
1291 * We let requests forced at head of queue with ide-preempt
1292 * though. I hope that doesn't happen too much, hopefully not
1293 * unless the subdriver triggers such a thing in its own PM
1294 * state machine.
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001295 *
1296 * We count how many times we loop here to make sure we service
1297 * all drives in the hwgroup without looping for ever
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298 */
Jens Axboe4aff5e22006-08-10 08:44:47 +02001299 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) {
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001300 drive = drive->next ? drive->next : hwgroup->drive;
1301 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1302 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303 /* We clear busy, there should be no pending ATA command at this point. */
1304 hwgroup->busy = 0;
1305 break;
1306 }
1307
1308 hwgroup->rq = rq;
1309
1310 /*
1311 * Some systems have trouble with IDE IRQs arriving while
1312 * the driver is still setting things up. So, here we disable
1313 * the IRQ used by this interface while the request is being started.
1314 * This may look bad at first, but pretty much the same thing
1315 * happens anyway when any interrupt comes in, IDE or otherwise
1316 * -- the kernel masks the IRQ while it is being handled.
1317 */
1318 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1319 disable_irq_nosync(hwif->irq);
1320 spin_unlock(&ide_lock);
Ingo Molnar366c7f52006-07-03 00:25:25 -07001321 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322 /* allow other IRQs while we start this request */
1323 startstop = start_request(drive, rq);
1324 spin_lock_irq(&ide_lock);
1325 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1326 enable_irq(hwif->irq);
1327 if (startstop == ide_stopped)
1328 hwgroup->busy = 0;
1329 }
1330}
1331
1332/*
1333 * Passes the stuff to ide_do_request
1334 */
Jens Axboe165125e2007-07-24 09:28:11 +02001335void do_ide_request(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001336{
1337 ide_drive_t *drive = q->queuedata;
1338
1339 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1340}
1341
1342/*
1343 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1344 * retry the current request in pio mode instead of risking tossing it
1345 * all away
1346 */
1347static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1348{
1349 ide_hwif_t *hwif = HWIF(drive);
1350 struct request *rq;
1351 ide_startstop_t ret = ide_stopped;
1352
1353 /*
1354 * end current dma transaction
1355 */
1356
1357 if (error < 0) {
1358 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1359 (void)HWIF(drive)->ide_dma_end(drive);
1360 ret = ide_error(drive, "dma timeout error",
1361 hwif->INB(IDE_STATUS_REG));
1362 } else {
1363 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
Sergei Shtylyovc283f5d2007-07-09 23:17:54 +02001364 hwif->dma_timeout(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001365 }
1366
1367 /*
1368 * disable dma for now, but remember that we did so because of
1369 * a timeout -- we'll reenable after we finish this next request
1370 * (or rather the first chunk of it) in pio.
1371 */
1372 drive->retry_pio++;
1373 drive->state = DMA_PIO_RETRY;
Bartlomiej Zolnierkiewicz7469aaf2007-02-17 02:40:26 +01001374 hwif->dma_off_quietly(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001375
1376 /*
1377 * un-busy drive etc (hwgroup->busy is cleared on return) and
1378 * make sure request is sane
1379 */
1380 rq = HWGROUP(drive)->rq;
Hua Zhongce42f192006-10-03 01:14:15 -07001381
1382 if (!rq)
1383 goto out;
1384
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385 HWGROUP(drive)->rq = NULL;
1386
1387 rq->errors = 0;
1388
1389 if (!rq->bio)
1390 goto out;
1391
1392 rq->sector = rq->bio->bi_sector;
1393 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1394 rq->hard_cur_sectors = rq->current_nr_sectors;
1395 rq->buffer = bio_data(rq->bio);
1396out:
1397 return ret;
1398}
1399
1400/**
1401 * ide_timer_expiry - handle lack of an IDE interrupt
1402 * @data: timer callback magic (hwgroup)
1403 *
1404 * An IDE command has timed out before the expected drive return
1405 * occurred. At this point we attempt to clean up the current
1406 * mess. If the current handler includes an expiry handler then
1407 * we invoke the expiry handler, and providing it is happy the
1408 * work is done. If that fails we apply generic recovery rules
1409 * invoking the handler and checking the drive DMA status. We
1410 * have an excessively incestuous relationship with the DMA
1411 * logic that wants cleaning up.
1412 */
1413
1414void ide_timer_expiry (unsigned long data)
1415{
1416 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1417 ide_handler_t *handler;
1418 ide_expiry_t *expiry;
1419 unsigned long flags;
1420 unsigned long wait = -1;
1421
1422 spin_lock_irqsave(&ide_lock, flags);
1423
Suleiman Souhlal23450312007-04-10 22:38:37 +02001424 if (((handler = hwgroup->handler) == NULL) ||
1425 (hwgroup->req_gen != hwgroup->req_gen_timer)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426 /*
1427 * Either a marginal timeout occurred
1428 * (got the interrupt just as timer expired),
1429 * or we were "sleeping" to give other devices a chance.
1430 * Either way, we don't really want to complain about anything.
1431 */
1432 if (hwgroup->sleeping) {
1433 hwgroup->sleeping = 0;
1434 hwgroup->busy = 0;
1435 }
1436 } else {
1437 ide_drive_t *drive = hwgroup->drive;
1438 if (!drive) {
1439 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1440 hwgroup->handler = NULL;
1441 } else {
1442 ide_hwif_t *hwif;
1443 ide_startstop_t startstop = ide_stopped;
1444 if (!hwgroup->busy) {
1445 hwgroup->busy = 1; /* paranoia */
1446 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1447 }
1448 if ((expiry = hwgroup->expiry) != NULL) {
1449 /* continue */
1450 if ((wait = expiry(drive)) > 0) {
1451 /* reset timer */
1452 hwgroup->timer.expires = jiffies + wait;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001453 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 add_timer(&hwgroup->timer);
1455 spin_unlock_irqrestore(&ide_lock, flags);
1456 return;
1457 }
1458 }
1459 hwgroup->handler = NULL;
1460 /*
1461 * We need to simulate a real interrupt when invoking
1462 * the handler() function, which means we need to
1463 * globally mask the specific IRQ:
1464 */
1465 spin_unlock(&ide_lock);
1466 hwif = HWIF(drive);
1467#if DISABLE_IRQ_NOSYNC
1468 disable_irq_nosync(hwif->irq);
1469#else
1470 /* disable_irq_nosync ?? */
1471 disable_irq(hwif->irq);
1472#endif /* DISABLE_IRQ_NOSYNC */
1473 /* local CPU only,
1474 * as if we were handling an interrupt */
1475 local_irq_disable();
1476 if (hwgroup->polling) {
1477 startstop = handler(drive);
1478 } else if (drive_is_ready(drive)) {
1479 if (drive->waiting_for_dma)
Sergei Shtylyov841d2a92007-07-09 23:17:54 +02001480 hwgroup->hwif->dma_lost_irq(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001481 (void)ide_ack_intr(hwif);
1482 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1483 startstop = handler(drive);
1484 } else {
1485 if (drive->waiting_for_dma) {
1486 startstop = ide_dma_timeout_retry(drive, wait);
1487 } else
1488 startstop =
1489 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG));
1490 }
1491 drive->service_time = jiffies - drive->service_start;
1492 spin_lock_irq(&ide_lock);
1493 enable_irq(hwif->irq);
1494 if (startstop == ide_stopped)
1495 hwgroup->busy = 0;
1496 }
1497 }
1498 ide_do_request(hwgroup, IDE_NO_IRQ);
1499 spin_unlock_irqrestore(&ide_lock, flags);
1500}
1501
1502/**
1503 * unexpected_intr - handle an unexpected IDE interrupt
1504 * @irq: interrupt line
1505 * @hwgroup: hwgroup being processed
1506 *
1507 * There's nothing really useful we can do with an unexpected interrupt,
1508 * other than reading the status register (to clear it), and logging it.
1509 * There should be no way that an irq can happen before we're ready for it,
1510 * so we needn't worry much about losing an "important" interrupt here.
1511 *
1512 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1513 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1514 * looks "good", we just ignore the interrupt completely.
1515 *
1516 * This routine assumes __cli() is in effect when called.
1517 *
1518 * If an unexpected interrupt happens on irq15 while we are handling irq14
1519 * and if the two interfaces are "serialized" (CMD640), then it looks like
1520 * we could screw up by interfering with a new request being set up for
1521 * irq15.
1522 *
1523 * In reality, this is a non-issue. The new command is not sent unless
1524 * the drive is ready to accept one, in which case we know the drive is
1525 * not trying to interrupt us. And ide_set_handler() is always invoked
1526 * before completing the issuance of any new drive command, so we will not
1527 * be accidentally invoked as a result of any valid command completion
1528 * interrupt.
1529 *
1530 * Note that we must walk the entire hwgroup here. We know which hwif
1531 * is doing the current command, but we don't know which hwif burped
1532 * mysteriously.
1533 */
1534
1535static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1536{
1537 u8 stat;
1538 ide_hwif_t *hwif = hwgroup->hwif;
1539
1540 /*
1541 * handle the unexpected interrupt
1542 */
1543 do {
1544 if (hwif->irq == irq) {
1545 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1546 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1547 /* Try to not flood the console with msgs */
1548 static unsigned long last_msgtime, count;
1549 ++count;
1550 if (time_after(jiffies, last_msgtime + HZ)) {
1551 last_msgtime = jiffies;
1552 printk(KERN_ERR "%s%s: unexpected interrupt, "
1553 "status=0x%02x, count=%ld\n",
1554 hwif->name,
1555 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1556 }
1557 }
1558 }
1559 } while ((hwif = hwif->next) != hwgroup->hwif);
1560}
1561
1562/**
1563 * ide_intr - default IDE interrupt handler
1564 * @irq: interrupt number
1565 * @dev_id: hwif group
1566 * @regs: unused weirdness from the kernel irq layer
1567 *
1568 * This is the default IRQ handler for the IDE layer. You should
1569 * not need to override it. If you do be aware it is subtle in
1570 * places
1571 *
1572 * hwgroup->hwif is the interface in the group currently performing
1573 * a command. hwgroup->drive is the drive and hwgroup->handler is
1574 * the IRQ handler to call. As we issue a command the handlers
1575 * step through multiple states, reassigning the handler to the
1576 * next step in the process. Unlike a smart SCSI controller IDE
1577 * expects the main processor to sequence the various transfer
1578 * stages. We also manage a poll timer to catch up with most
1579 * timeout situations. There are still a few where the handlers
1580 * don't ever decide to give up.
1581 *
1582 * The handler eventually returns ide_stopped to indicate the
1583 * request completed. At this point we issue the next request
1584 * on the hwgroup and the process begins again.
1585 */
1586
David Howells7d12e782006-10-05 14:55:46 +01001587irqreturn_t ide_intr (int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588{
1589 unsigned long flags;
1590 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1591 ide_hwif_t *hwif;
1592 ide_drive_t *drive;
1593 ide_handler_t *handler;
1594 ide_startstop_t startstop;
1595
1596 spin_lock_irqsave(&ide_lock, flags);
1597 hwif = hwgroup->hwif;
1598
1599 if (!ide_ack_intr(hwif)) {
1600 spin_unlock_irqrestore(&ide_lock, flags);
1601 return IRQ_NONE;
1602 }
1603
1604 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1605 /*
1606 * Not expecting an interrupt from this drive.
1607 * That means this could be:
1608 * (1) an interrupt from another PCI device
1609 * sharing the same PCI INT# as us.
1610 * or (2) a drive just entered sleep or standby mode,
1611 * and is interrupting to let us know.
1612 * or (3) a spurious interrupt of unknown origin.
1613 *
1614 * For PCI, we cannot tell the difference,
1615 * so in that case we just ignore it and hope it goes away.
1616 *
1617 * FIXME: unexpected_intr should be hwif-> then we can
1618 * remove all the ifdef PCI crap
1619 */
1620#ifdef CONFIG_BLK_DEV_IDEPCI
1621 if (hwif->pci_dev && !hwif->pci_dev->vendor)
1622#endif /* CONFIG_BLK_DEV_IDEPCI */
1623 {
1624 /*
1625 * Probably not a shared PCI interrupt,
1626 * so we can safely try to do something about it:
1627 */
1628 unexpected_intr(irq, hwgroup);
1629#ifdef CONFIG_BLK_DEV_IDEPCI
1630 } else {
1631 /*
1632 * Whack the status register, just in case
1633 * we have a leftover pending IRQ.
1634 */
1635 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1636#endif /* CONFIG_BLK_DEV_IDEPCI */
1637 }
1638 spin_unlock_irqrestore(&ide_lock, flags);
1639 return IRQ_NONE;
1640 }
1641 drive = hwgroup->drive;
1642 if (!drive) {
1643 /*
1644 * This should NEVER happen, and there isn't much
1645 * we could do about it here.
1646 *
1647 * [Note - this can occur if the drive is hot unplugged]
1648 */
1649 spin_unlock_irqrestore(&ide_lock, flags);
1650 return IRQ_HANDLED;
1651 }
1652 if (!drive_is_ready(drive)) {
1653 /*
1654 * This happens regularly when we share a PCI IRQ with
1655 * another device. Unfortunately, it can also happen
1656 * with some buggy drives that trigger the IRQ before
1657 * their status register is up to date. Hopefully we have
1658 * enough advance overhead that the latter isn't a problem.
1659 */
1660 spin_unlock_irqrestore(&ide_lock, flags);
1661 return IRQ_NONE;
1662 }
1663 if (!hwgroup->busy) {
1664 hwgroup->busy = 1; /* paranoia */
1665 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1666 }
1667 hwgroup->handler = NULL;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001668 hwgroup->req_gen++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669 del_timer(&hwgroup->timer);
1670 spin_unlock(&ide_lock);
1671
Albert Leef0dd8712007-02-17 02:40:21 +01001672 /* Some controllers might set DMA INTR no matter DMA or PIO;
1673 * bmdma status might need to be cleared even for
1674 * PIO interrupts to prevent spurious/lost irq.
1675 */
1676 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma))
1677 /* ide_dma_end() needs bmdma status for error checking.
1678 * So, skip clearing bmdma status here and leave it
1679 * to ide_dma_end() if this is dma interrupt.
1680 */
1681 hwif->ide_dma_clear_irq(drive);
1682
Linus Torvalds1da177e2005-04-16 15:20:36 -07001683 if (drive->unmask)
Ingo Molnar366c7f52006-07-03 00:25:25 -07001684 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685 /* service this interrupt, may set handler for next interrupt */
1686 startstop = handler(drive);
1687 spin_lock_irq(&ide_lock);
1688
1689 /*
1690 * Note that handler() may have set things up for another
1691 * interrupt to occur soon, but it cannot happen until
1692 * we exit from this routine, because it will be the
1693 * same irq as is currently being serviced here, and Linux
1694 * won't allow another of the same (on any CPU) until we return.
1695 */
1696 drive->service_time = jiffies - drive->service_start;
1697 if (startstop == ide_stopped) {
1698 if (hwgroup->handler == NULL) { /* paranoia */
1699 hwgroup->busy = 0;
1700 ide_do_request(hwgroup, hwif->irq);
1701 } else {
1702 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1703 "on exit\n", drive->name);
1704 }
1705 }
1706 spin_unlock_irqrestore(&ide_lock, flags);
1707 return IRQ_HANDLED;
1708}
1709
1710/**
1711 * ide_init_drive_cmd - initialize a drive command request
1712 * @rq: request object
1713 *
1714 * Initialize a request before we fill it in and send it down to
1715 * ide_do_drive_cmd. Commands must be set up by this function. Right
1716 * now it doesn't do a lot, but if that changes abusers will have a
Andreas Mohrd6e05ed2006-06-26 18:35:02 +02001717 * nasty surprise.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001718 */
1719
1720void ide_init_drive_cmd (struct request *rq)
1721{
1722 memset(rq, 0, sizeof(*rq));
Jens Axboe4aff5e22006-08-10 08:44:47 +02001723 rq->cmd_type = REQ_TYPE_ATA_CMD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001724 rq->ref_count = 1;
1725}
1726
1727EXPORT_SYMBOL(ide_init_drive_cmd);
1728
1729/**
1730 * ide_do_drive_cmd - issue IDE special command
1731 * @drive: device to issue command
1732 * @rq: request to issue
1733 * @action: action for processing
1734 *
1735 * This function issues a special IDE device request
1736 * onto the request queue.
1737 *
1738 * If action is ide_wait, then the rq is queued at the end of the
1739 * request queue, and the function sleeps until it has been processed.
1740 * This is for use when invoked from an ioctl handler.
1741 *
1742 * If action is ide_preempt, then the rq is queued at the head of
1743 * the request queue, displacing the currently-being-processed
1744 * request and this function returns immediately without waiting
1745 * for the new rq to be completed. This is VERY DANGEROUS, and is
1746 * intended for careful use by the ATAPI tape/cdrom driver code.
1747 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001748 * If action is ide_end, then the rq is queued at the end of the
1749 * request queue, and the function returns immediately without waiting
1750 * for the new rq to be completed. This is again intended for careful
1751 * use by the ATAPI tape/cdrom driver code.
1752 */
1753
1754int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1755{
1756 unsigned long flags;
1757 ide_hwgroup_t *hwgroup = HWGROUP(drive);
Ingo Molnar60be6b92006-07-03 00:25:26 -07001758 DECLARE_COMPLETION_ONSTACK(wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001759 int where = ELEVATOR_INSERT_BACK, err;
1760 int must_wait = (action == ide_wait || action == ide_head_wait);
1761
1762 rq->errors = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001763
1764 /*
1765 * we need to hold an extra reference to request for safe inspection
1766 * after completion
1767 */
1768 if (must_wait) {
1769 rq->ref_count++;
Jens Axboec00895a2006-09-30 20:29:12 +02001770 rq->end_io_data = &wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771 rq->end_io = blk_end_sync_rq;
1772 }
1773
1774 spin_lock_irqsave(&ide_lock, flags);
1775 if (action == ide_preempt)
1776 hwgroup->rq = NULL;
1777 if (action == ide_preempt || action == ide_head_wait) {
1778 where = ELEVATOR_INSERT_FRONT;
Jens Axboe4aff5e22006-08-10 08:44:47 +02001779 rq->cmd_flags |= REQ_PREEMPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001780 }
1781 __elv_add_request(drive->queue, rq, where, 0);
1782 ide_do_request(hwgroup, IDE_NO_IRQ);
1783 spin_unlock_irqrestore(&ide_lock, flags);
1784
1785 err = 0;
1786 if (must_wait) {
1787 wait_for_completion(&wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001788 if (rq->errors)
1789 err = -EIO;
1790
1791 blk_put_request(rq);
1792 }
1793
1794 return err;
1795}
1796
1797EXPORT_SYMBOL(ide_do_drive_cmd);