blob: 715379605a7bb55f887eb887832c4765eccab485 [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,
Bartlomiej Zolnierkiewiczbbc615b2007-10-20 00:32:36 +020058 int uptodate, unsigned int nr_bytes, int dequeue)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059{
60 int ret = 1;
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +010061 int error = 0;
62
63 if (uptodate <= 0)
64 error = uptodate ? uptodate : -EIO;
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 /*
67 * if failfast is set on a request, override number of sectors and
68 * complete the whole request right now
69 */
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +010070 if (blk_noretry_request(rq) && error)
Jens Axboe41e9d342007-07-19 08:13:01 +020071 nr_bytes = rq->hard_nr_sectors << 9;
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +010073 if (!blk_fs_request(rq) && error && !rq->errors)
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 rq->errors = -EIO;
75
76 /*
77 * decide whether to reenable DMA -- 3 is a random magic for now,
78 * if we DMA timeout more than 3 times, just stay in PIO
79 */
80 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
81 drive->state = 0;
Bartlomiej Zolnierkiewicz4a546e02008-01-26 20:13:01 +010082 ide_dma_on(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083 }
84
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +010085 if (!__blk_end_request(rq, error, nr_bytes)) {
86 if (dequeue)
Bartlomiej Zolnierkiewiczbbc615b2007-10-20 00:32:36 +020087 HWGROUP(drive)->rq = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 ret = 0;
89 }
Jens Axboe8672d572006-01-09 16:03:35 +010090
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 return ret;
92}
Linus Torvalds1da177e2005-04-16 15:20:36 -070093
94/**
95 * ide_end_request - complete an IDE I/O
96 * @drive: IDE device for the I/O
97 * @uptodate:
98 * @nr_sectors: number of sectors completed
99 *
100 * This is our end_request wrapper function. We complete the I/O
101 * update random number input and dequeue the request, which if
102 * it was tagged may be out of order.
103 */
104
105int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
106{
Jens Axboe41e9d342007-07-19 08:13:01 +0200107 unsigned int nr_bytes = nr_sectors << 9;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 struct request *rq;
109 unsigned long flags;
110 int ret = 1;
111
Jens Axboe8672d572006-01-09 16:03:35 +0100112 /*
113 * room for locking improvements here, the calls below don't
114 * need the queue lock held at all
115 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 spin_lock_irqsave(&ide_lock, flags);
117 rq = HWGROUP(drive)->rq;
118
Jens Axboe41e9d342007-07-19 08:13:01 +0200119 if (!nr_bytes) {
120 if (blk_pc_request(rq))
121 nr_bytes = rq->data_len;
122 else
123 nr_bytes = rq->hard_cur_sectors << 9;
124 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
Bartlomiej Zolnierkiewiczbbc615b2007-10-20 00:32:36 +0200126 ret = __ide_end_request(drive, rq, uptodate, nr_bytes, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127
128 spin_unlock_irqrestore(&ide_lock, flags);
129 return ret;
130}
131EXPORT_SYMBOL(ide_end_request);
132
133/*
134 * Power Management state machine. This one is rather trivial for now,
135 * we should probably add more, like switching back to PIO on suspend
136 * to help some BIOSes, re-do the door locking on resume, etc...
137 */
138
139enum {
140 ide_pm_flush_cache = ide_pm_state_start_suspend,
141 idedisk_pm_standby,
142
Jason Lunz8c2c0112006-10-03 01:14:26 -0700143 idedisk_pm_restore_pio = ide_pm_state_start_resume,
144 idedisk_pm_idle,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 ide_pm_restore_dma,
146};
147
148static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error)
149{
Jens Axboec00895a2006-09-30 20:29:12 +0200150 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200151
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 if (drive->media != ide_disk)
153 return;
154
Jens Axboead3cadd2006-06-13 08:46:57 +0200155 switch (pm->pm_step) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */
Jens Axboead3cadd2006-06-13 08:46:57 +0200157 if (pm->pm_state == PM_EVENT_FREEZE)
158 pm->pm_step = ide_pm_state_completed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 else
Jens Axboead3cadd2006-06-13 08:46:57 +0200160 pm->pm_step = idedisk_pm_standby;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 break;
162 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */
Jens Axboead3cadd2006-06-13 08:46:57 +0200163 pm->pm_step = ide_pm_state_completed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 break;
Jason Lunz8c2c0112006-10-03 01:14:26 -0700165 case idedisk_pm_restore_pio: /* Resume step 1 complete */
166 pm->pm_step = idedisk_pm_idle;
167 break;
168 case idedisk_pm_idle: /* Resume step 2 (idle) complete */
Jens Axboead3cadd2006-06-13 08:46:57 +0200169 pm->pm_step = ide_pm_restore_dma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 break;
171 }
172}
173
174static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq)
175{
Jens Axboec00895a2006-09-30 20:29:12 +0200176 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 ide_task_t *args = rq->special;
178
179 memset(args, 0, sizeof(*args));
180
Jens Axboead3cadd2006-06-13 08:46:57 +0200181 switch (pm->pm_step) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */
183 if (drive->media != ide_disk)
184 break;
185 /* Not supported? Switch to next step now. */
186 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) {
187 ide_complete_power_step(drive, rq, 0, 0);
188 return ide_stopped;
189 }
190 if (ide_id_has_flush_cache_ext(drive->id))
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100191 args->tf.command = WIN_FLUSH_CACHE_EXT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192 else
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100193 args->tf.command = WIN_FLUSH_CACHE;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100194 goto out_do_tf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195
196 case idedisk_pm_standby: /* Suspend step 2 (standby) */
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100197 args->tf.command = WIN_STANDBYNOW1;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100198 goto out_do_tf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199
Jason Lunz8c2c0112006-10-03 01:14:26 -0700200 case idedisk_pm_restore_pio: /* Resume step 1 (restore PIO) */
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200201 ide_set_max_pio(drive);
Bartlomiej Zolnierkiewicz317a46a2007-05-10 00:01:11 +0200202 /*
203 * skip idedisk_pm_idle for ATAPI devices
204 */
205 if (drive->media != ide_disk)
206 pm->pm_step = ide_pm_restore_dma;
207 else
208 ide_complete_power_step(drive, rq, 0, 0);
Jason Lunz8c2c0112006-10-03 01:14:26 -0700209 return ide_stopped;
210
211 case idedisk_pm_idle: /* Resume step 2 (idle) */
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100212 args->tf.command = WIN_IDLEIMMEDIATE;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100213 goto out_do_tf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
Jason Lunz8c2c0112006-10-03 01:14:26 -0700215 case ide_pm_restore_dma: /* Resume step 3 (restore DMA) */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 /*
Bartlomiej Zolnierkiewicz0ae2e172007-10-16 22:29:55 +0200217 * Right now, all we do is call ide_set_dma(drive),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 * we could be smarter and check for current xfer_speed
219 * in struct drive etc...
220 */
Bartlomiej Zolnierkiewicz15ce9262008-01-26 20:13:03 +0100221 if (drive->hwif->dma_host_set == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 break;
Bartlomiej Zolnierkiewicz8987d212007-07-20 01:11:56 +0200223 /*
224 * TODO: respect ->using_dma setting
225 */
Bartlomiej Zolnierkiewicz3608b5d2007-02-17 02:40:26 +0100226 ide_set_dma(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227 break;
228 }
Jens Axboead3cadd2006-06-13 08:46:57 +0200229 pm->pm_step = ide_pm_state_completed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 return ide_stopped;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100231
232out_do_tf:
Bartlomiej Zolnierkiewicz657cc1a2008-01-26 20:13:10 +0100233 args->tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE;
Bartlomiej Zolnierkiewiczac026ff2008-01-25 22:17:14 +0100234 args->data_phase = TASKFILE_NO_DATA;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100235 return do_rw_taskfile(drive, args);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236}
237
238/**
Alan Coxdbe217a2006-06-25 05:47:44 -0700239 * ide_end_dequeued_request - complete an IDE I/O
240 * @drive: IDE device for the I/O
241 * @uptodate:
242 * @nr_sectors: number of sectors completed
243 *
244 * Complete an I/O that is no longer on the request queue. This
245 * typically occurs when we pull the request and issue a REQUEST_SENSE.
246 * We must still finish the old request but we must not tamper with the
247 * queue in the meantime.
248 *
249 * NOTE: This path does not handle barrier, but barrier is not supported
250 * on ide-cd anyway.
251 */
252
253int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
254 int uptodate, int nr_sectors)
255{
256 unsigned long flags;
Bartlomiej Zolnierkiewiczbbc615b2007-10-20 00:32:36 +0200257 int ret;
Alan Coxdbe217a2006-06-25 05:47:44 -0700258
259 spin_lock_irqsave(&ide_lock, flags);
Jens Axboe4aff5e22006-08-10 08:44:47 +0200260 BUG_ON(!blk_rq_started(rq));
Bartlomiej Zolnierkiewiczbbc615b2007-10-20 00:32:36 +0200261 ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0);
Alan Coxdbe217a2006-06-25 05:47:44 -0700262 spin_unlock_irqrestore(&ide_lock, flags);
Bartlomiej Zolnierkiewiczbbc615b2007-10-20 00:32:36 +0200263
Alan Coxdbe217a2006-06-25 05:47:44 -0700264 return ret;
265}
266EXPORT_SYMBOL_GPL(ide_end_dequeued_request);
267
268
269/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 * ide_complete_pm_request - end the current Power Management request
271 * @drive: target drive
272 * @rq: request
273 *
274 * This function cleans up the current PM request and stops the queue
275 * if necessary.
276 */
277static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
278{
279 unsigned long flags;
280
281#ifdef DEBUG_PM
282 printk("%s: completing PM request, %s\n", drive->name,
283 blk_pm_suspend_request(rq) ? "suspend" : "resume");
284#endif
285 spin_lock_irqsave(&ide_lock, flags);
286 if (blk_pm_suspend_request(rq)) {
287 blk_stop_queue(drive->queue);
288 } else {
289 drive->blocked = 0;
290 blk_start_queue(drive->queue);
291 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 HWGROUP(drive)->rq = NULL;
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +0100293 if (__blk_end_request(rq, 0, 0))
294 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 spin_unlock_irqrestore(&ide_lock, flags);
296}
297
Bartlomiej Zolnierkiewiczc2b57cd2008-01-25 22:17:17 +0100298void ide_tf_read(ide_drive_t *drive, ide_task_t *task)
299{
300 ide_hwif_t *hwif = drive->hwif;
301 struct ide_taskfile *tf = &task->tf;
302
303 if (task->tf_flags & IDE_TFLAG_IN_DATA) {
304 u16 data = hwif->INW(IDE_DATA_REG);
305
306 tf->data = data & 0xff;
307 tf->hob_data = (data >> 8) & 0xff;
308 }
309
310 /* be sure we're looking at the low order bits */
311 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG);
312
313 if (task->tf_flags & IDE_TFLAG_IN_NSECT)
314 tf->nsect = hwif->INB(IDE_NSECTOR_REG);
315 if (task->tf_flags & IDE_TFLAG_IN_LBAL)
316 tf->lbal = hwif->INB(IDE_SECTOR_REG);
317 if (task->tf_flags & IDE_TFLAG_IN_LBAM)
318 tf->lbam = hwif->INB(IDE_LCYL_REG);
319 if (task->tf_flags & IDE_TFLAG_IN_LBAH)
320 tf->lbah = hwif->INB(IDE_HCYL_REG);
321 if (task->tf_flags & IDE_TFLAG_IN_DEVICE)
322 tf->device = hwif->INB(IDE_SELECT_REG);
323
324 if (task->tf_flags & IDE_TFLAG_LBA48) {
325 hwif->OUTB(drive->ctl | 0x80, IDE_CONTROL_REG);
326
327 if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE)
328 tf->hob_feature = hwif->INB(IDE_FEATURE_REG);
329 if (task->tf_flags & IDE_TFLAG_IN_HOB_NSECT)
330 tf->hob_nsect = hwif->INB(IDE_NSECTOR_REG);
331 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAL)
332 tf->hob_lbal = hwif->INB(IDE_SECTOR_REG);
333 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAM)
334 tf->hob_lbam = hwif->INB(IDE_LCYL_REG);
335 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAH)
336 tf->hob_lbah = hwif->INB(IDE_HCYL_REG);
337 }
338}
339
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340/**
341 * ide_end_drive_cmd - end an explicit drive command
342 * @drive: command
343 * @stat: status bits
344 * @err: error bits
345 *
346 * Clean up after success/failure of an explicit drive command.
347 * These get thrown onto the queue so they are synchronized with
348 * real I/O operations on the drive.
349 *
350 * In LBA48 mode we have to read the register set twice to get
351 * all the extra information out.
352 */
353
354void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
355{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 unsigned long flags;
357 struct request *rq;
358
359 spin_lock_irqsave(&ide_lock, flags);
360 rq = HWGROUP(drive)->rq;
361 spin_unlock_irqrestore(&ide_lock, flags);
362
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100363 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
Bartlomiej Zolnierkiewicz395d8ef2008-02-11 00:32:14 +0100364 ide_task_t *task = (ide_task_t *)rq->special;
365
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 if (rq->errors == 0)
Bartlomiej Zolnierkiewicz395d8ef2008-02-11 00:32:14 +0100367 rq->errors = !OK_STAT(stat, READY_STAT, BAD_STAT);
368
369 if (task) {
370 struct ide_taskfile *tf = &task->tf;
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100371
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100372 tf->error = err;
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100373 tf->status = stat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374
Bartlomiej Zolnierkiewicz395d8ef2008-02-11 00:32:14 +0100375 ide_tf_read(drive, task);
376
377 if (task->tf_flags & IDE_TFLAG_DYN)
378 kfree(task);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 }
380 } else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200381 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382#ifdef DEBUG_PM
383 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
384 drive->name, rq->pm->pm_step, stat, err);
385#endif
386 ide_complete_power_step(drive, rq, stat, err);
Jens Axboead3cadd2006-06-13 08:46:57 +0200387 if (pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 ide_complete_pm_request(drive, rq);
389 return;
390 }
391
392 spin_lock_irqsave(&ide_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 HWGROUP(drive)->rq = NULL;
394 rq->errors = err;
Kiyoshi Ueda3b0e0442008-02-11 00:32:11 +0100395 if (unlikely(__blk_end_request(rq, (rq->errors ? -EIO : 0),
396 blk_rq_bytes(rq))))
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +0100397 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 spin_unlock_irqrestore(&ide_lock, flags);
399}
400
401EXPORT_SYMBOL(ide_end_drive_cmd);
402
403/**
404 * try_to_flush_leftover_data - flush junk
405 * @drive: drive to flush
406 *
407 * try_to_flush_leftover_data() is invoked in response to a drive
408 * unexpectedly having its DRQ_STAT bit set. As an alternative to
409 * resetting the drive, this routine tries to clear the condition
410 * by read a sector's worth of data from the drive. Of course,
411 * this may not help if the drive is *waiting* for data from *us*.
412 */
413static void try_to_flush_leftover_data (ide_drive_t *drive)
414{
415 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;
416
417 if (drive->media != ide_disk)
418 return;
419 while (i > 0) {
420 u32 buffer[16];
421 u32 wcount = (i > 16) ? 16 : i;
422
423 i -= wcount;
424 HWIF(drive)->ata_input_data(drive, buffer, wcount);
425 }
426}
427
428static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
429{
430 if (rq->rq_disk) {
431 ide_driver_t *drv;
432
433 drv = *(ide_driver_t **)rq->rq_disk->private_data;
434 drv->end_request(drive, 0, 0);
435 } else
436 ide_end_request(drive, 0, 0);
437}
438
439static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
440{
441 ide_hwif_t *hwif = drive->hwif;
442
443 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
444 /* other bits are useless when BUSY */
445 rq->errors |= ERROR_RESET;
446 } else if (stat & ERR_STAT) {
447 /* err has different meaning on cdrom and tape */
448 if (err == ABRT_ERR) {
449 if (drive->select.b.lba &&
450 /* some newer drives don't support WIN_SPECIFY */
451 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
452 return ide_stopped;
453 } else if ((err & BAD_CRC) == BAD_CRC) {
454 /* UDMA crc error, just retry the operation */
455 drive->crc_count++;
456 } else if (err & (BBD_ERR | ECC_ERR)) {
457 /* retries won't help these */
458 rq->errors = ERROR_MAX;
459 } else if (err & TRK0_ERR) {
460 /* help it find track zero */
461 rq->errors |= ERROR_RECAL;
462 }
463 }
464
Bartlomiej Zolnierkiewiczed67b922007-10-19 00:30:10 +0200465 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ &&
466 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 try_to_flush_leftover_data(drive);
468
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200469 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 ide_kill_rq(drive, rq);
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200471 return ide_stopped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472 }
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200473
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +0100474 if (ide_read_status(drive) & (BUSY_STAT | DRQ_STAT))
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200475 rq->errors |= ERROR_RESET;
476
477 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
478 ++rq->errors;
479 return ide_do_reset(drive);
480 }
481
482 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
483 drive->special.b.recalibrate = 1;
484
485 ++rq->errors;
486
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487 return ide_stopped;
488}
489
490static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
491{
492 ide_hwif_t *hwif = drive->hwif;
493
494 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
495 /* other bits are useless when BUSY */
496 rq->errors |= ERROR_RESET;
497 } else {
498 /* add decoding error stuff */
499 }
500
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +0100501 if (ide_read_status(drive) & (BUSY_STAT | DRQ_STAT))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502 /* force an abort */
503 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
504
505 if (rq->errors >= ERROR_MAX) {
506 ide_kill_rq(drive, rq);
507 } else {
508 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
509 ++rq->errors;
510 return ide_do_reset(drive);
511 }
512 ++rq->errors;
513 }
514
515 return ide_stopped;
516}
517
518ide_startstop_t
519__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
520{
521 if (drive->media == ide_disk)
522 return ide_ata_error(drive, rq, stat, err);
523 return ide_atapi_error(drive, rq, stat, err);
524}
525
526EXPORT_SYMBOL_GPL(__ide_error);
527
528/**
529 * ide_error - handle an error on the IDE
530 * @drive: drive the error occurred on
531 * @msg: message to report
532 * @stat: status bits
533 *
534 * ide_error() takes action based on the error returned by the drive.
535 * For normal I/O that may well include retries. We deal with
536 * both new-style (taskfile) and old style command handling here.
537 * In the case of taskfile command handling there is work left to
538 * do
539 */
540
541ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
542{
543 struct request *rq;
544 u8 err;
545
546 err = ide_dump_status(drive, msg, stat);
547
548 if ((rq = HWGROUP(drive)->rq) == NULL)
549 return ide_stopped;
550
551 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200552 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 rq->errors = 1;
554 ide_end_drive_cmd(drive, stat, err);
555 return ide_stopped;
556 }
557
558 if (rq->rq_disk) {
559 ide_driver_t *drv;
560
561 drv = *(ide_driver_t **)rq->rq_disk->private_data;
562 return drv->error(drive, rq, stat, err);
563 } else
564 return __ide_error(drive, rq, stat, err);
565}
566
567EXPORT_SYMBOL_GPL(ide_error);
568
569ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
570{
571 if (drive->media != ide_disk)
572 rq->errors |= ERROR_RESET;
573
574 ide_kill_rq(drive, rq);
575
576 return ide_stopped;
577}
578
579EXPORT_SYMBOL_GPL(__ide_abort);
580
581/**
Adrian Bunk338cec32005-09-10 00:26:54 -0700582 * ide_abort - abort pending IDE operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 * @drive: drive the error occurred on
584 * @msg: message to report
585 *
586 * ide_abort kills and cleans up when we are about to do a
587 * host initiated reset on active commands. Longer term we
588 * want handlers to have sensible abort handling themselves
589 *
590 * This differs fundamentally from ide_error because in
591 * this case the command is doing just fine when we
592 * blow it away.
593 */
594
595ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
596{
597 struct request *rq;
598
599 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
600 return ide_stopped;
601
602 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200603 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 rq->errors = 1;
605 ide_end_drive_cmd(drive, BUSY_STAT, 0);
606 return ide_stopped;
607 }
608
609 if (rq->rq_disk) {
610 ide_driver_t *drv;
611
612 drv = *(ide_driver_t **)rq->rq_disk->private_data;
613 return drv->abort(drive, rq);
614 } else
615 return __ide_abort(drive, rq);
616}
617
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100618static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100620 tf->nsect = drive->sect;
621 tf->lbal = drive->sect;
622 tf->lbam = drive->cyl;
623 tf->lbah = drive->cyl >> 8;
624 tf->device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA;
625 tf->command = WIN_SPECIFY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626}
627
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100628static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100630 tf->nsect = drive->sect;
631 tf->command = WIN_RESTORE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632}
633
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100634static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100636 tf->nsect = drive->mult_req;
637 tf->command = WIN_SETMULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638}
639
640static ide_startstop_t ide_disk_special(ide_drive_t *drive)
641{
642 special_t *s = &drive->special;
643 ide_task_t args;
644
645 memset(&args, 0, sizeof(ide_task_t));
Bartlomiej Zolnierkiewiczac026ff2008-01-25 22:17:14 +0100646 args.data_phase = TASKFILE_NO_DATA;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647
648 if (s->b.set_geometry) {
649 s->b.set_geometry = 0;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100650 ide_tf_set_specify_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 } else if (s->b.recalibrate) {
652 s->b.recalibrate = 0;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100653 ide_tf_set_restore_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 } else if (s->b.set_multmode) {
655 s->b.set_multmode = 0;
656 if (drive->mult_req > drive->id->max_multsect)
657 drive->mult_req = drive->id->max_multsect;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100658 ide_tf_set_setmult_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 } else if (s->all) {
660 int special = s->all;
661 s->all = 0;
662 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
663 return ide_stopped;
664 }
665
Bartlomiej Zolnierkiewicz657cc1a2008-01-26 20:13:10 +0100666 args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE |
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100667 IDE_TFLAG_CUSTOM_HANDLER;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100668
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 do_rw_taskfile(drive, &args);
670
671 return ide_started;
672}
673
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200674/*
675 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
676 */
677static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio)
678{
679 switch (req_pio) {
680 case 202:
681 case 201:
682 case 200:
683 case 102:
684 case 101:
685 case 100:
686 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0;
687 case 9:
688 case 8:
689 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0;
690 case 7:
691 case 6:
692 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0;
693 default:
694 return 0;
695 }
696}
697
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698/**
699 * do_special - issue some special commands
700 * @drive: drive the command is for
701 *
702 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
703 * commands to a drive. It used to do much more, but has been scaled
704 * back.
705 */
706
707static ide_startstop_t do_special (ide_drive_t *drive)
708{
709 special_t *s = &drive->special;
710
711#ifdef DEBUG
712 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
713#endif
714 if (s->b.set_tune) {
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200715 ide_hwif_t *hwif = drive->hwif;
716 u8 req_pio = drive->tune_req;
717
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718 s->b.set_tune = 0;
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200719
720 if (set_pio_mode_abuse(drive->hwif, req_pio)) {
Bartlomiej Zolnierkiewiczd393aa02007-10-20 00:32:36 +0200721
722 if (hwif->set_pio_mode == NULL)
723 return ide_stopped;
724
725 /*
726 * take ide_lock for drive->[no_]unmask/[no_]io_32bit
727 */
728 if (req_pio == 8 || req_pio == 9) {
729 unsigned long flags;
730
731 spin_lock_irqsave(&ide_lock, flags);
732 hwif->set_pio_mode(drive, req_pio);
733 spin_unlock_irqrestore(&ide_lock, flags);
734 } else
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200735 hwif->set_pio_mode(drive, req_pio);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200736 } else {
737 int keep_dma = drive->using_dma;
738
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200739 ide_set_pio(drive, req_pio);
740
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200741 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) {
742 if (keep_dma)
Bartlomiej Zolnierkiewicz4a546e02008-01-26 20:13:01 +0100743 ide_dma_on(drive);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200744 }
745 }
746
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 return ide_stopped;
748 } else {
749 if (drive->media == ide_disk)
750 return ide_disk_special(drive);
751
752 s->all = 0;
753 drive->mult_req = 0;
754 return ide_stopped;
755 }
756}
757
758void ide_map_sg(ide_drive_t *drive, struct request *rq)
759{
760 ide_hwif_t *hwif = drive->hwif;
761 struct scatterlist *sg = hwif->sg_table;
762
763 if (hwif->sg_mapped) /* needed by ide-scsi */
764 return;
765
Jens Axboe4aff5e22006-08-10 08:44:47 +0200766 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
768 } else {
769 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
770 hwif->sg_nents = 1;
771 }
772}
773
774EXPORT_SYMBOL_GPL(ide_map_sg);
775
776void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
777{
778 ide_hwif_t *hwif = drive->hwif;
779
780 hwif->nsect = hwif->nleft = rq->nr_sectors;
Jens Axboe55c16a72007-07-25 08:13:56 +0200781 hwif->cursg_ofs = 0;
782 hwif->cursg = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700783}
784
785EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
786
787/**
788 * execute_drive_command - issue special drive command
Adrian Bunk338cec32005-09-10 00:26:54 -0700789 * @drive: the drive to issue the command on
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 * @rq: the request structure holding the command
791 *
792 * execute_drive_cmd() issues a special drive command, usually
793 * initiated by ioctl() from the external hdparm program. The
794 * command can be a drive command, drive task or taskfile
795 * operation. Weirdly you can call it with NULL to wait for
796 * all commands to finish. Don't do this as that is due to change
797 */
798
799static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
800 struct request *rq)
801{
802 ide_hwif_t *hwif = HWIF(drive);
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100803 ide_task_t *task = rq->special;
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100804
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100805 if (task) {
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100806 hwif->data_phase = task->data_phase;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700807
808 switch (hwif->data_phase) {
809 case TASKFILE_MULTI_OUT:
810 case TASKFILE_OUT:
811 case TASKFILE_MULTI_IN:
812 case TASKFILE_IN:
813 ide_init_sg_cmd(drive, rq);
814 ide_map_sg(drive, rq);
815 default:
816 break;
817 }
818
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100819 return do_rw_taskfile(drive, task);
820 }
821
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822 /*
823 * NULL is actually a valid way of waiting for
824 * all current requests to be flushed from the queue.
825 */
826#ifdef DEBUG
827 printk("%s: DRIVE_CMD (null)\n", drive->name);
828#endif
Bartlomiej Zolnierkiewicz64a57fe2008-02-06 02:57:51 +0100829 ide_end_drive_cmd(drive, ide_read_status(drive), ide_read_error(drive));
830
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831 return ide_stopped;
832}
833
Jens Axboead3cadd2006-06-13 08:46:57 +0200834static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
835{
Jens Axboec00895a2006-09-30 20:29:12 +0200836 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200837
838 if (blk_pm_suspend_request(rq) &&
839 pm->pm_step == ide_pm_state_start_suspend)
840 /* Mark drive blocked when starting the suspend sequence. */
841 drive->blocked = 1;
842 else if (blk_pm_resume_request(rq) &&
843 pm->pm_step == ide_pm_state_start_resume) {
844 /*
845 * The first thing we do on wakeup is to wait for BSY bit to
846 * go away (with a looong timeout) as a drive on this hwif may
847 * just be POSTing itself.
848 * We do that before even selecting as the "other" device on
849 * the bus may be broken enough to walk on our toes at this
850 * point.
851 */
852 int rc;
853#ifdef DEBUG_PM
854 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
855#endif
856 rc = ide_wait_not_busy(HWIF(drive), 35000);
857 if (rc)
858 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
859 SELECT_DRIVE(drive);
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +0100860 ide_set_irq(drive, 1);
Al Boldi178184b2006-06-26 00:26:13 -0700861 rc = ide_wait_not_busy(HWIF(drive), 100000);
Jens Axboead3cadd2006-06-13 08:46:57 +0200862 if (rc)
863 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
864 }
865}
866
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867/**
868 * start_request - start of I/O and command issuing for IDE
869 *
870 * start_request() initiates handling of a new I/O request. It
871 * accepts commands and I/O (read/write) requests. It also does
872 * the final remapping for weird stuff like EZDrive. Once
873 * device mapper can work sector level the EZDrive stuff can go away
874 *
875 * FIXME: this function needs a rename
876 */
877
878static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
879{
880 ide_startstop_t startstop;
881 sector_t block;
882
Jens Axboe4aff5e22006-08-10 08:44:47 +0200883 BUG_ON(!blk_rq_started(rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884
885#ifdef DEBUG
886 printk("%s: start_request: current=0x%08lx\n",
887 HWIF(drive)->name, (unsigned long) rq);
888#endif
889
890 /* bail early if we've exceeded max_failures */
891 if (drive->max_failures && (drive->failures > drive->max_failures)) {
Aristeu Rozanskib5e1a4e2008-01-25 22:17:04 +0100892 rq->cmd_flags |= REQ_FAILED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893 goto kill_rq;
894 }
895
896 block = rq->sector;
897 if (blk_fs_request(rq) &&
898 (drive->media == ide_disk || drive->media == ide_floppy)) {
899 block += drive->sect0;
900 }
901 /* Yecch - this will shift the entire interval,
902 possibly killing some innocent following sector */
903 if (block == 0 && drive->remap_0_to_1 == 1)
904 block = 1; /* redirect MBR access to EZ-Drive partn table */
905
Jens Axboead3cadd2006-06-13 08:46:57 +0200906 if (blk_pm_request(rq))
907 ide_check_pm_state(drive, rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908
909 SELECT_DRIVE(drive);
910 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
911 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
912 return startstop;
913 }
914 if (!drive->special.all) {
915 ide_driver_t *drv;
916
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200917 /*
918 * We reset the drive so we need to issue a SETFEATURES.
919 * Do it _after_ do_special() restored device parameters.
920 */
921 if (drive->current_speed == 0xff)
922 ide_config_drive_speed(drive, drive->desired_speed);
923
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100924 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 return execute_drive_cmd(drive, rq);
926 else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200927 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928#ifdef DEBUG_PM
929 printk("%s: start_power_step(step: %d)\n",
930 drive->name, rq->pm->pm_step);
931#endif
932 startstop = ide_start_power_step(drive, rq);
933 if (startstop == ide_stopped &&
Jens Axboead3cadd2006-06-13 08:46:57 +0200934 pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935 ide_complete_pm_request(drive, rq);
936 return startstop;
937 }
938
939 drv = *(ide_driver_t **)rq->rq_disk->private_data;
940 return drv->do_request(drive, rq, block);
941 }
942 return do_special(drive);
943kill_rq:
944 ide_kill_rq(drive, rq);
945 return ide_stopped;
946}
947
948/**
949 * ide_stall_queue - pause an IDE device
950 * @drive: drive to stall
951 * @timeout: time to stall for (jiffies)
952 *
953 * ide_stall_queue() can be used by a drive to give excess bandwidth back
954 * to the hwgroup by sleeping for timeout jiffies.
955 */
956
957void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
958{
959 if (timeout > WAIT_WORSTCASE)
960 timeout = WAIT_WORSTCASE;
961 drive->sleep = timeout + jiffies;
962 drive->sleeping = 1;
963}
964
965EXPORT_SYMBOL(ide_stall_queue);
966
967#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
968
969/**
970 * choose_drive - select a drive to service
971 * @hwgroup: hardware group to select on
972 *
973 * choose_drive() selects the next drive which will be serviced.
974 * This is necessary because the IDE layer can't issue commands
975 * to both drives on the same cable, unlike SCSI.
976 */
977
978static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
979{
980 ide_drive_t *drive, *best;
981
982repeat:
983 best = NULL;
984 drive = hwgroup->drive;
985
986 /*
987 * drive is doing pre-flush, ordered write, post-flush sequence. even
988 * though that is 3 requests, it must be seen as a single transaction.
989 * we must not preempt this drive until that is complete
990 */
991 if (blk_queue_flushing(drive->queue)) {
992 /*
993 * small race where queue could get replugged during
994 * the 3-request flush cycle, just yank the plug since
995 * we want it to finish asap
996 */
997 blk_remove_plug(drive->queue);
998 return drive;
999 }
1000
1001 do {
1002 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
1003 && !elv_queue_empty(drive->queue)) {
1004 if (!best
1005 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
1006 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
1007 {
1008 if (!blk_queue_plugged(drive->queue))
1009 best = drive;
1010 }
1011 }
1012 } while ((drive = drive->next) != hwgroup->drive);
1013 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1014 long t = (signed long)(WAKEUP(best) - jiffies);
1015 if (t >= WAIT_MIN_SLEEP) {
1016 /*
1017 * We *may* have some time to spare, but first let's see if
1018 * someone can potentially benefit from our nice mood today..
1019 */
1020 drive = best->next;
1021 do {
1022 if (!drive->sleeping
1023 && time_before(jiffies - best->service_time, WAKEUP(drive))
1024 && time_before(WAKEUP(drive), jiffies + t))
1025 {
1026 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1027 goto repeat;
1028 }
1029 } while ((drive = drive->next) != best);
1030 }
1031 }
1032 return best;
1033}
1034
1035/*
1036 * Issue a new request to a drive from hwgroup
1037 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1038 *
1039 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1040 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1041 * may have both interfaces in a single hwgroup to "serialize" access.
1042 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1043 * together into one hwgroup for serialized access.
1044 *
1045 * Note also that several hwgroups can end up sharing a single IRQ,
1046 * possibly along with many other devices. This is especially common in
1047 * PCI-based systems with off-board IDE controller cards.
1048 *
1049 * The IDE driver uses the single global ide_lock spinlock to protect
1050 * access to the request queues, and to protect the hwgroup->busy flag.
1051 *
1052 * The first thread into the driver for a particular hwgroup sets the
1053 * hwgroup->busy flag to indicate that this hwgroup is now active,
1054 * and then initiates processing of the top request from the request queue.
1055 *
1056 * Other threads attempting entry notice the busy setting, and will simply
1057 * queue their new requests and exit immediately. Note that hwgroup->busy
1058 * remains set even when the driver is merely awaiting the next interrupt.
1059 * Thus, the meaning is "this hwgroup is busy processing a request".
1060 *
1061 * When processing of a request completes, the completing thread or IRQ-handler
1062 * will start the next request from the queue. If no more work remains,
1063 * the driver will clear the hwgroup->busy flag and exit.
1064 *
1065 * The ide_lock (spinlock) is used to protect all access to the
1066 * hwgroup->busy flag, but is otherwise not needed for most processing in
1067 * the driver. This makes the driver much more friendlier to shared IRQs
1068 * than previous designs, while remaining 100% (?) SMP safe and capable.
1069 */
1070static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1071{
1072 ide_drive_t *drive;
1073 ide_hwif_t *hwif;
1074 struct request *rq;
1075 ide_startstop_t startstop;
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001076 int loops = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001077
1078 /* for atari only: POSSIBLY BROKEN HERE(?) */
1079 ide_get_lock(ide_intr, hwgroup);
1080
1081 /* caller must own ide_lock */
1082 BUG_ON(!irqs_disabled());
1083
1084 while (!hwgroup->busy) {
1085 hwgroup->busy = 1;
1086 drive = choose_drive(hwgroup);
1087 if (drive == NULL) {
1088 int sleeping = 0;
1089 unsigned long sleep = 0; /* shut up, gcc */
1090 hwgroup->rq = NULL;
1091 drive = hwgroup->drive;
1092 do {
1093 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1094 sleeping = 1;
1095 sleep = drive->sleep;
1096 }
1097 } while ((drive = drive->next) != hwgroup->drive);
1098 if (sleeping) {
1099 /*
1100 * Take a short snooze, and then wake up this hwgroup again.
1101 * This gives other hwgroups on the same a chance to
1102 * play fairly with us, just in case there are big differences
1103 * in relative throughputs.. don't want to hog the cpu too much.
1104 */
1105 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1106 sleep = jiffies + WAIT_MIN_SLEEP;
1107#if 1
1108 if (timer_pending(&hwgroup->timer))
1109 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1110#endif
1111 /* so that ide_timer_expiry knows what to do */
1112 hwgroup->sleeping = 1;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001113 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001114 mod_timer(&hwgroup->timer, sleep);
1115 /* we purposely leave hwgroup->busy==1
1116 * while sleeping */
1117 } else {
1118 /* Ugly, but how can we sleep for the lock
1119 * otherwise? perhaps from tq_disk?
1120 */
1121
1122 /* for atari only */
1123 ide_release_lock();
1124 hwgroup->busy = 0;
1125 }
1126
1127 /* no more work for this hwgroup (for now) */
1128 return;
1129 }
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001130 again:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001131 hwif = HWIF(drive);
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +01001132 if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) {
Bartlomiej Zolnierkiewicz7299a392008-01-25 22:17:14 +01001133 /*
1134 * set nIEN for previous hwif, drives in the
1135 * quirk_list may not like intr setups/cleanups
1136 */
1137 if (drive->quirk_list != 1)
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +01001138 ide_set_irq(drive, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001139 }
1140 hwgroup->hwif = hwif;
1141 hwgroup->drive = drive;
1142 drive->sleeping = 0;
1143 drive->service_start = jiffies;
1144
1145 if (blk_queue_plugged(drive->queue)) {
1146 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1147 break;
1148 }
1149
1150 /*
1151 * we know that the queue isn't empty, but this can happen
1152 * if the q->prep_rq_fn() decides to kill a request
1153 */
1154 rq = elv_next_request(drive->queue);
1155 if (!rq) {
1156 hwgroup->busy = 0;
1157 break;
1158 }
1159
1160 /*
1161 * Sanity: don't accept a request that isn't a PM request
1162 * if we are currently power managed. This is very important as
1163 * blk_stop_queue() doesn't prevent the elv_next_request()
1164 * above to return us whatever is in the queue. Since we call
1165 * ide_do_request() ourselves, we end up taking requests while
1166 * the queue is blocked...
1167 *
1168 * We let requests forced at head of queue with ide-preempt
1169 * though. I hope that doesn't happen too much, hopefully not
1170 * unless the subdriver triggers such a thing in its own PM
1171 * state machine.
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001172 *
1173 * We count how many times we loop here to make sure we service
1174 * all drives in the hwgroup without looping for ever
Linus Torvalds1da177e2005-04-16 15:20:36 -07001175 */
Jens Axboe4aff5e22006-08-10 08:44:47 +02001176 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) {
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001177 drive = drive->next ? drive->next : hwgroup->drive;
1178 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1179 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 /* We clear busy, there should be no pending ATA command at this point. */
1181 hwgroup->busy = 0;
1182 break;
1183 }
1184
1185 hwgroup->rq = rq;
1186
1187 /*
1188 * Some systems have trouble with IDE IRQs arriving while
1189 * the driver is still setting things up. So, here we disable
1190 * the IRQ used by this interface while the request is being started.
1191 * This may look bad at first, but pretty much the same thing
1192 * happens anyway when any interrupt comes in, IDE or otherwise
1193 * -- the kernel masks the IRQ while it is being handled.
1194 */
1195 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1196 disable_irq_nosync(hwif->irq);
1197 spin_unlock(&ide_lock);
Ingo Molnar366c7f52006-07-03 00:25:25 -07001198 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001199 /* allow other IRQs while we start this request */
1200 startstop = start_request(drive, rq);
1201 spin_lock_irq(&ide_lock);
1202 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1203 enable_irq(hwif->irq);
1204 if (startstop == ide_stopped)
1205 hwgroup->busy = 0;
1206 }
1207}
1208
1209/*
1210 * Passes the stuff to ide_do_request
1211 */
Jens Axboe165125e2007-07-24 09:28:11 +02001212void do_ide_request(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001213{
1214 ide_drive_t *drive = q->queuedata;
1215
1216 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1217}
1218
1219/*
1220 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1221 * retry the current request in pio mode instead of risking tossing it
1222 * all away
1223 */
1224static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1225{
1226 ide_hwif_t *hwif = HWIF(drive);
1227 struct request *rq;
1228 ide_startstop_t ret = ide_stopped;
1229
1230 /*
1231 * end current dma transaction
1232 */
1233
1234 if (error < 0) {
1235 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1236 (void)HWIF(drive)->ide_dma_end(drive);
1237 ret = ide_error(drive, "dma timeout error",
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +01001238 ide_read_status(drive));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001239 } else {
1240 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
Sergei Shtylyovc283f5d2007-07-09 23:17:54 +02001241 hwif->dma_timeout(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001242 }
1243
1244 /*
1245 * disable dma for now, but remember that we did so because of
1246 * a timeout -- we'll reenable after we finish this next request
1247 * (or rather the first chunk of it) in pio.
1248 */
1249 drive->retry_pio++;
1250 drive->state = DMA_PIO_RETRY;
Bartlomiej Zolnierkiewicz4a546e02008-01-26 20:13:01 +01001251 ide_dma_off_quietly(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252
1253 /*
1254 * un-busy drive etc (hwgroup->busy is cleared on return) and
1255 * make sure request is sane
1256 */
1257 rq = HWGROUP(drive)->rq;
Hua Zhongce42f192006-10-03 01:14:15 -07001258
1259 if (!rq)
1260 goto out;
1261
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262 HWGROUP(drive)->rq = NULL;
1263
1264 rq->errors = 0;
1265
1266 if (!rq->bio)
1267 goto out;
1268
1269 rq->sector = rq->bio->bi_sector;
1270 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1271 rq->hard_cur_sectors = rq->current_nr_sectors;
1272 rq->buffer = bio_data(rq->bio);
1273out:
1274 return ret;
1275}
1276
1277/**
1278 * ide_timer_expiry - handle lack of an IDE interrupt
1279 * @data: timer callback magic (hwgroup)
1280 *
1281 * An IDE command has timed out before the expected drive return
1282 * occurred. At this point we attempt to clean up the current
1283 * mess. If the current handler includes an expiry handler then
1284 * we invoke the expiry handler, and providing it is happy the
1285 * work is done. If that fails we apply generic recovery rules
1286 * invoking the handler and checking the drive DMA status. We
1287 * have an excessively incestuous relationship with the DMA
1288 * logic that wants cleaning up.
1289 */
1290
1291void ide_timer_expiry (unsigned long data)
1292{
1293 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1294 ide_handler_t *handler;
1295 ide_expiry_t *expiry;
1296 unsigned long flags;
1297 unsigned long wait = -1;
1298
1299 spin_lock_irqsave(&ide_lock, flags);
1300
Suleiman Souhlal23450312007-04-10 22:38:37 +02001301 if (((handler = hwgroup->handler) == NULL) ||
1302 (hwgroup->req_gen != hwgroup->req_gen_timer)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303 /*
1304 * Either a marginal timeout occurred
1305 * (got the interrupt just as timer expired),
1306 * or we were "sleeping" to give other devices a chance.
1307 * Either way, we don't really want to complain about anything.
1308 */
1309 if (hwgroup->sleeping) {
1310 hwgroup->sleeping = 0;
1311 hwgroup->busy = 0;
1312 }
1313 } else {
1314 ide_drive_t *drive = hwgroup->drive;
1315 if (!drive) {
1316 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1317 hwgroup->handler = NULL;
1318 } else {
1319 ide_hwif_t *hwif;
1320 ide_startstop_t startstop = ide_stopped;
1321 if (!hwgroup->busy) {
1322 hwgroup->busy = 1; /* paranoia */
1323 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1324 }
1325 if ((expiry = hwgroup->expiry) != NULL) {
1326 /* continue */
1327 if ((wait = expiry(drive)) > 0) {
1328 /* reset timer */
1329 hwgroup->timer.expires = jiffies + wait;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001330 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331 add_timer(&hwgroup->timer);
1332 spin_unlock_irqrestore(&ide_lock, flags);
1333 return;
1334 }
1335 }
1336 hwgroup->handler = NULL;
1337 /*
1338 * We need to simulate a real interrupt when invoking
1339 * the handler() function, which means we need to
1340 * globally mask the specific IRQ:
1341 */
1342 spin_unlock(&ide_lock);
1343 hwif = HWIF(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001344 /* disable_irq_nosync ?? */
1345 disable_irq(hwif->irq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 /* local CPU only,
1347 * as if we were handling an interrupt */
1348 local_irq_disable();
1349 if (hwgroup->polling) {
1350 startstop = handler(drive);
1351 } else if (drive_is_ready(drive)) {
1352 if (drive->waiting_for_dma)
Sergei Shtylyov841d2a92007-07-09 23:17:54 +02001353 hwgroup->hwif->dma_lost_irq(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354 (void)ide_ack_intr(hwif);
1355 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1356 startstop = handler(drive);
1357 } else {
1358 if (drive->waiting_for_dma) {
1359 startstop = ide_dma_timeout_retry(drive, wait);
1360 } else
1361 startstop =
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +01001362 ide_error(drive, "irq timeout",
1363 ide_read_status(drive));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364 }
1365 drive->service_time = jiffies - drive->service_start;
1366 spin_lock_irq(&ide_lock);
1367 enable_irq(hwif->irq);
1368 if (startstop == ide_stopped)
1369 hwgroup->busy = 0;
1370 }
1371 }
1372 ide_do_request(hwgroup, IDE_NO_IRQ);
1373 spin_unlock_irqrestore(&ide_lock, flags);
1374}
1375
1376/**
1377 * unexpected_intr - handle an unexpected IDE interrupt
1378 * @irq: interrupt line
1379 * @hwgroup: hwgroup being processed
1380 *
1381 * There's nothing really useful we can do with an unexpected interrupt,
1382 * other than reading the status register (to clear it), and logging it.
1383 * There should be no way that an irq can happen before we're ready for it,
1384 * so we needn't worry much about losing an "important" interrupt here.
1385 *
1386 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1387 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1388 * looks "good", we just ignore the interrupt completely.
1389 *
1390 * This routine assumes __cli() is in effect when called.
1391 *
1392 * If an unexpected interrupt happens on irq15 while we are handling irq14
1393 * and if the two interfaces are "serialized" (CMD640), then it looks like
1394 * we could screw up by interfering with a new request being set up for
1395 * irq15.
1396 *
1397 * In reality, this is a non-issue. The new command is not sent unless
1398 * the drive is ready to accept one, in which case we know the drive is
1399 * not trying to interrupt us. And ide_set_handler() is always invoked
1400 * before completing the issuance of any new drive command, so we will not
1401 * be accidentally invoked as a result of any valid command completion
1402 * interrupt.
1403 *
1404 * Note that we must walk the entire hwgroup here. We know which hwif
1405 * is doing the current command, but we don't know which hwif burped
1406 * mysteriously.
1407 */
1408
1409static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1410{
1411 u8 stat;
1412 ide_hwif_t *hwif = hwgroup->hwif;
1413
1414 /*
1415 * handle the unexpected interrupt
1416 */
1417 do {
1418 if (hwif->irq == irq) {
1419 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1420 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1421 /* Try to not flood the console with msgs */
1422 static unsigned long last_msgtime, count;
1423 ++count;
1424 if (time_after(jiffies, last_msgtime + HZ)) {
1425 last_msgtime = jiffies;
1426 printk(KERN_ERR "%s%s: unexpected interrupt, "
1427 "status=0x%02x, count=%ld\n",
1428 hwif->name,
1429 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1430 }
1431 }
1432 }
1433 } while ((hwif = hwif->next) != hwgroup->hwif);
1434}
1435
1436/**
1437 * ide_intr - default IDE interrupt handler
1438 * @irq: interrupt number
1439 * @dev_id: hwif group
1440 * @regs: unused weirdness from the kernel irq layer
1441 *
1442 * This is the default IRQ handler for the IDE layer. You should
1443 * not need to override it. If you do be aware it is subtle in
1444 * places
1445 *
1446 * hwgroup->hwif is the interface in the group currently performing
1447 * a command. hwgroup->drive is the drive and hwgroup->handler is
1448 * the IRQ handler to call. As we issue a command the handlers
1449 * step through multiple states, reassigning the handler to the
1450 * next step in the process. Unlike a smart SCSI controller IDE
1451 * expects the main processor to sequence the various transfer
1452 * stages. We also manage a poll timer to catch up with most
1453 * timeout situations. There are still a few where the handlers
1454 * don't ever decide to give up.
1455 *
1456 * The handler eventually returns ide_stopped to indicate the
1457 * request completed. At this point we issue the next request
1458 * on the hwgroup and the process begins again.
1459 */
1460
David Howells7d12e782006-10-05 14:55:46 +01001461irqreturn_t ide_intr (int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001462{
1463 unsigned long flags;
1464 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1465 ide_hwif_t *hwif;
1466 ide_drive_t *drive;
1467 ide_handler_t *handler;
1468 ide_startstop_t startstop;
1469
1470 spin_lock_irqsave(&ide_lock, flags);
1471 hwif = hwgroup->hwif;
1472
1473 if (!ide_ack_intr(hwif)) {
1474 spin_unlock_irqrestore(&ide_lock, flags);
1475 return IRQ_NONE;
1476 }
1477
1478 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1479 /*
1480 * Not expecting an interrupt from this drive.
1481 * That means this could be:
1482 * (1) an interrupt from another PCI device
1483 * sharing the same PCI INT# as us.
1484 * or (2) a drive just entered sleep or standby mode,
1485 * and is interrupting to let us know.
1486 * or (3) a spurious interrupt of unknown origin.
1487 *
1488 * For PCI, we cannot tell the difference,
1489 * so in that case we just ignore it and hope it goes away.
1490 *
1491 * FIXME: unexpected_intr should be hwif-> then we can
1492 * remove all the ifdef PCI crap
1493 */
1494#ifdef CONFIG_BLK_DEV_IDEPCI
Bartlomiej Zolnierkiewicz425afb62008-02-01 23:09:31 +01001495 if (hwif->chipset != ide_pci)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496#endif /* CONFIG_BLK_DEV_IDEPCI */
1497 {
1498 /*
1499 * Probably not a shared PCI interrupt,
1500 * so we can safely try to do something about it:
1501 */
1502 unexpected_intr(irq, hwgroup);
1503#ifdef CONFIG_BLK_DEV_IDEPCI
1504 } else {
1505 /*
1506 * Whack the status register, just in case
1507 * we have a leftover pending IRQ.
1508 */
1509 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1510#endif /* CONFIG_BLK_DEV_IDEPCI */
1511 }
1512 spin_unlock_irqrestore(&ide_lock, flags);
1513 return IRQ_NONE;
1514 }
1515 drive = hwgroup->drive;
1516 if (!drive) {
1517 /*
1518 * This should NEVER happen, and there isn't much
1519 * we could do about it here.
1520 *
1521 * [Note - this can occur if the drive is hot unplugged]
1522 */
1523 spin_unlock_irqrestore(&ide_lock, flags);
1524 return IRQ_HANDLED;
1525 }
1526 if (!drive_is_ready(drive)) {
1527 /*
1528 * This happens regularly when we share a PCI IRQ with
1529 * another device. Unfortunately, it can also happen
1530 * with some buggy drives that trigger the IRQ before
1531 * their status register is up to date. Hopefully we have
1532 * enough advance overhead that the latter isn't a problem.
1533 */
1534 spin_unlock_irqrestore(&ide_lock, flags);
1535 return IRQ_NONE;
1536 }
1537 if (!hwgroup->busy) {
1538 hwgroup->busy = 1; /* paranoia */
1539 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1540 }
1541 hwgroup->handler = NULL;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001542 hwgroup->req_gen++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001543 del_timer(&hwgroup->timer);
1544 spin_unlock(&ide_lock);
1545
Albert Leef0dd8712007-02-17 02:40:21 +01001546 /* Some controllers might set DMA INTR no matter DMA or PIO;
1547 * bmdma status might need to be cleared even for
1548 * PIO interrupts to prevent spurious/lost irq.
1549 */
1550 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma))
1551 /* ide_dma_end() needs bmdma status for error checking.
1552 * So, skip clearing bmdma status here and leave it
1553 * to ide_dma_end() if this is dma interrupt.
1554 */
1555 hwif->ide_dma_clear_irq(drive);
1556
Linus Torvalds1da177e2005-04-16 15:20:36 -07001557 if (drive->unmask)
Ingo Molnar366c7f52006-07-03 00:25:25 -07001558 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001559 /* service this interrupt, may set handler for next interrupt */
1560 startstop = handler(drive);
1561 spin_lock_irq(&ide_lock);
1562
1563 /*
1564 * Note that handler() may have set things up for another
1565 * interrupt to occur soon, but it cannot happen until
1566 * we exit from this routine, because it will be the
1567 * same irq as is currently being serviced here, and Linux
1568 * won't allow another of the same (on any CPU) until we return.
1569 */
1570 drive->service_time = jiffies - drive->service_start;
1571 if (startstop == ide_stopped) {
1572 if (hwgroup->handler == NULL) { /* paranoia */
1573 hwgroup->busy = 0;
1574 ide_do_request(hwgroup, hwif->irq);
1575 } else {
1576 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1577 "on exit\n", drive->name);
1578 }
1579 }
1580 spin_unlock_irqrestore(&ide_lock, flags);
1581 return IRQ_HANDLED;
1582}
1583
1584/**
1585 * ide_init_drive_cmd - initialize a drive command request
1586 * @rq: request object
1587 *
1588 * Initialize a request before we fill it in and send it down to
1589 * ide_do_drive_cmd. Commands must be set up by this function. Right
1590 * now it doesn't do a lot, but if that changes abusers will have a
Andreas Mohrd6e05ed2006-06-26 18:35:02 +02001591 * nasty surprise.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001592 */
1593
1594void ide_init_drive_cmd (struct request *rq)
1595{
1596 memset(rq, 0, sizeof(*rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001597 rq->ref_count = 1;
1598}
1599
1600EXPORT_SYMBOL(ide_init_drive_cmd);
1601
1602/**
1603 * ide_do_drive_cmd - issue IDE special command
1604 * @drive: device to issue command
1605 * @rq: request to issue
1606 * @action: action for processing
1607 *
1608 * This function issues a special IDE device request
1609 * onto the request queue.
1610 *
1611 * If action is ide_wait, then the rq is queued at the end of the
1612 * request queue, and the function sleeps until it has been processed.
1613 * This is for use when invoked from an ioctl handler.
1614 *
1615 * If action is ide_preempt, then the rq is queued at the head of
1616 * the request queue, displacing the currently-being-processed
1617 * request and this function returns immediately without waiting
1618 * for the new rq to be completed. This is VERY DANGEROUS, and is
1619 * intended for careful use by the ATAPI tape/cdrom driver code.
1620 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001621 * If action is ide_end, then the rq is queued at the end of the
1622 * request queue, and the function returns immediately without waiting
1623 * for the new rq to be completed. This is again intended for careful
1624 * use by the ATAPI tape/cdrom driver code.
1625 */
1626
1627int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1628{
1629 unsigned long flags;
1630 ide_hwgroup_t *hwgroup = HWGROUP(drive);
Ingo Molnar60be6b92006-07-03 00:25:26 -07001631 DECLARE_COMPLETION_ONSTACK(wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001632 int where = ELEVATOR_INSERT_BACK, err;
1633 int must_wait = (action == ide_wait || action == ide_head_wait);
1634
1635 rq->errors = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636
1637 /*
1638 * we need to hold an extra reference to request for safe inspection
1639 * after completion
1640 */
1641 if (must_wait) {
1642 rq->ref_count++;
Jens Axboec00895a2006-09-30 20:29:12 +02001643 rq->end_io_data = &wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001644 rq->end_io = blk_end_sync_rq;
1645 }
1646
1647 spin_lock_irqsave(&ide_lock, flags);
1648 if (action == ide_preempt)
1649 hwgroup->rq = NULL;
1650 if (action == ide_preempt || action == ide_head_wait) {
1651 where = ELEVATOR_INSERT_FRONT;
Jens Axboe4aff5e22006-08-10 08:44:47 +02001652 rq->cmd_flags |= REQ_PREEMPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653 }
1654 __elv_add_request(drive->queue, rq, where, 0);
1655 ide_do_request(hwgroup, IDE_NO_IRQ);
1656 spin_unlock_irqrestore(&ide_lock, flags);
1657
1658 err = 0;
1659 if (must_wait) {
1660 wait_for_completion(&wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661 if (rq->errors)
1662 err = -EIO;
1663
1664 blk_put_request(rq);
1665 }
1666
1667 return err;
1668}
1669
1670EXPORT_SYMBOL(ide_do_drive_cmd);
Bartlomiej Zolnierkiewicz2fc57382008-01-25 22:17:13 +01001671
1672void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma)
1673{
1674 ide_task_t task;
1675
1676 memset(&task, 0, sizeof(task));
1677 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
1678 IDE_TFLAG_OUT_FEATURE | tf_flags;
1679 task.tf.feature = dma; /* Use PIO/DMA */
1680 task.tf.lbam = bcount & 0xff;
1681 task.tf.lbah = (bcount >> 8) & 0xff;
1682
1683 ide_tf_load(drive, &task);
1684}
1685
1686EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load);