blob: e6bb9cf24e3d8f3fcbd599319fb693fdfe497019 [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) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364 ide_task_t *args = (ide_task_t *) rq->special;
365 if (rq->errors == 0)
366 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
367
368 if (args) {
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100369 struct ide_taskfile *tf = &args->tf;
370
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100371 tf->error = err;
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100372 tf->status = stat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373
Bartlomiej Zolnierkiewiczc2b57cd2008-01-25 22:17:17 +0100374 ide_tf_read(drive, args);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 }
376 } else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200377 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378#ifdef DEBUG_PM
379 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
380 drive->name, rq->pm->pm_step, stat, err);
381#endif
382 ide_complete_power_step(drive, rq, stat, err);
Jens Axboead3cadd2006-06-13 08:46:57 +0200383 if (pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700384 ide_complete_pm_request(drive, rq);
385 return;
386 }
387
388 spin_lock_irqsave(&ide_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389 HWGROUP(drive)->rq = NULL;
390 rq->errors = err;
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +0100391 if (__blk_end_request(rq, (rq->errors ? -EIO : 0), 0))
392 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 spin_unlock_irqrestore(&ide_lock, flags);
394}
395
396EXPORT_SYMBOL(ide_end_drive_cmd);
397
398/**
399 * try_to_flush_leftover_data - flush junk
400 * @drive: drive to flush
401 *
402 * try_to_flush_leftover_data() is invoked in response to a drive
403 * unexpectedly having its DRQ_STAT bit set. As an alternative to
404 * resetting the drive, this routine tries to clear the condition
405 * by read a sector's worth of data from the drive. Of course,
406 * this may not help if the drive is *waiting* for data from *us*.
407 */
408static void try_to_flush_leftover_data (ide_drive_t *drive)
409{
410 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;
411
412 if (drive->media != ide_disk)
413 return;
414 while (i > 0) {
415 u32 buffer[16];
416 u32 wcount = (i > 16) ? 16 : i;
417
418 i -= wcount;
419 HWIF(drive)->ata_input_data(drive, buffer, wcount);
420 }
421}
422
423static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
424{
425 if (rq->rq_disk) {
426 ide_driver_t *drv;
427
428 drv = *(ide_driver_t **)rq->rq_disk->private_data;
429 drv->end_request(drive, 0, 0);
430 } else
431 ide_end_request(drive, 0, 0);
432}
433
434static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
435{
436 ide_hwif_t *hwif = drive->hwif;
437
438 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
439 /* other bits are useless when BUSY */
440 rq->errors |= ERROR_RESET;
441 } else if (stat & ERR_STAT) {
442 /* err has different meaning on cdrom and tape */
443 if (err == ABRT_ERR) {
444 if (drive->select.b.lba &&
445 /* some newer drives don't support WIN_SPECIFY */
446 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
447 return ide_stopped;
448 } else if ((err & BAD_CRC) == BAD_CRC) {
449 /* UDMA crc error, just retry the operation */
450 drive->crc_count++;
451 } else if (err & (BBD_ERR | ECC_ERR)) {
452 /* retries won't help these */
453 rq->errors = ERROR_MAX;
454 } else if (err & TRK0_ERR) {
455 /* help it find track zero */
456 rq->errors |= ERROR_RECAL;
457 }
458 }
459
Bartlomiej Zolnierkiewiczed67b922007-10-19 00:30:10 +0200460 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ &&
461 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 try_to_flush_leftover_data(drive);
463
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200464 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 ide_kill_rq(drive, rq);
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200466 return ide_stopped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 }
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200468
469 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
470 rq->errors |= ERROR_RESET;
471
472 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
473 ++rq->errors;
474 return ide_do_reset(drive);
475 }
476
477 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
478 drive->special.b.recalibrate = 1;
479
480 ++rq->errors;
481
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482 return ide_stopped;
483}
484
485static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
486{
487 ide_hwif_t *hwif = drive->hwif;
488
489 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
490 /* other bits are useless when BUSY */
491 rq->errors |= ERROR_RESET;
492 } else {
493 /* add decoding error stuff */
494 }
495
496 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
497 /* force an abort */
498 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
499
500 if (rq->errors >= ERROR_MAX) {
501 ide_kill_rq(drive, rq);
502 } else {
503 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
504 ++rq->errors;
505 return ide_do_reset(drive);
506 }
507 ++rq->errors;
508 }
509
510 return ide_stopped;
511}
512
513ide_startstop_t
514__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
515{
516 if (drive->media == ide_disk)
517 return ide_ata_error(drive, rq, stat, err);
518 return ide_atapi_error(drive, rq, stat, err);
519}
520
521EXPORT_SYMBOL_GPL(__ide_error);
522
523/**
524 * ide_error - handle an error on the IDE
525 * @drive: drive the error occurred on
526 * @msg: message to report
527 * @stat: status bits
528 *
529 * ide_error() takes action based on the error returned by the drive.
530 * For normal I/O that may well include retries. We deal with
531 * both new-style (taskfile) and old style command handling here.
532 * In the case of taskfile command handling there is work left to
533 * do
534 */
535
536ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
537{
538 struct request *rq;
539 u8 err;
540
541 err = ide_dump_status(drive, msg, stat);
542
543 if ((rq = HWGROUP(drive)->rq) == NULL)
544 return ide_stopped;
545
546 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200547 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548 rq->errors = 1;
549 ide_end_drive_cmd(drive, stat, err);
550 return ide_stopped;
551 }
552
553 if (rq->rq_disk) {
554 ide_driver_t *drv;
555
556 drv = *(ide_driver_t **)rq->rq_disk->private_data;
557 return drv->error(drive, rq, stat, err);
558 } else
559 return __ide_error(drive, rq, stat, err);
560}
561
562EXPORT_SYMBOL_GPL(ide_error);
563
564ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
565{
566 if (drive->media != ide_disk)
567 rq->errors |= ERROR_RESET;
568
569 ide_kill_rq(drive, rq);
570
571 return ide_stopped;
572}
573
574EXPORT_SYMBOL_GPL(__ide_abort);
575
576/**
Adrian Bunk338cec32005-09-10 00:26:54 -0700577 * ide_abort - abort pending IDE operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 * @drive: drive the error occurred on
579 * @msg: message to report
580 *
581 * ide_abort kills and cleans up when we are about to do a
582 * host initiated reset on active commands. Longer term we
583 * want handlers to have sensible abort handling themselves
584 *
585 * This differs fundamentally from ide_error because in
586 * this case the command is doing just fine when we
587 * blow it away.
588 */
589
590ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
591{
592 struct request *rq;
593
594 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
595 return ide_stopped;
596
597 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200598 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599 rq->errors = 1;
600 ide_end_drive_cmd(drive, BUSY_STAT, 0);
601 return ide_stopped;
602 }
603
604 if (rq->rq_disk) {
605 ide_driver_t *drv;
606
607 drv = *(ide_driver_t **)rq->rq_disk->private_data;
608 return drv->abort(drive, rq);
609 } else
610 return __ide_abort(drive, rq);
611}
612
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100613static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700614{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100615 tf->nsect = drive->sect;
616 tf->lbal = drive->sect;
617 tf->lbam = drive->cyl;
618 tf->lbah = drive->cyl >> 8;
619 tf->device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA;
620 tf->command = WIN_SPECIFY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621}
622
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100623static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100625 tf->nsect = drive->sect;
626 tf->command = WIN_RESTORE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627}
628
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100629static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100631 tf->nsect = drive->mult_req;
632 tf->command = WIN_SETMULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633}
634
635static ide_startstop_t ide_disk_special(ide_drive_t *drive)
636{
637 special_t *s = &drive->special;
638 ide_task_t args;
639
640 memset(&args, 0, sizeof(ide_task_t));
Bartlomiej Zolnierkiewiczac026ff2008-01-25 22:17:14 +0100641 args.data_phase = TASKFILE_NO_DATA;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642
643 if (s->b.set_geometry) {
644 s->b.set_geometry = 0;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100645 ide_tf_set_specify_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 } else if (s->b.recalibrate) {
647 s->b.recalibrate = 0;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100648 ide_tf_set_restore_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649 } else if (s->b.set_multmode) {
650 s->b.set_multmode = 0;
651 if (drive->mult_req > drive->id->max_multsect)
652 drive->mult_req = drive->id->max_multsect;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100653 ide_tf_set_setmult_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 } else if (s->all) {
655 int special = s->all;
656 s->all = 0;
657 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
658 return ide_stopped;
659 }
660
Bartlomiej Zolnierkiewicz657cc1a2008-01-26 20:13:10 +0100661 args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE |
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100662 IDE_TFLAG_CUSTOM_HANDLER;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100663
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 do_rw_taskfile(drive, &args);
665
666 return ide_started;
667}
668
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200669/*
670 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
671 */
672static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio)
673{
674 switch (req_pio) {
675 case 202:
676 case 201:
677 case 200:
678 case 102:
679 case 101:
680 case 100:
681 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0;
682 case 9:
683 case 8:
684 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0;
685 case 7:
686 case 6:
687 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0;
688 default:
689 return 0;
690 }
691}
692
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693/**
694 * do_special - issue some special commands
695 * @drive: drive the command is for
696 *
697 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
698 * commands to a drive. It used to do much more, but has been scaled
699 * back.
700 */
701
702static ide_startstop_t do_special (ide_drive_t *drive)
703{
704 special_t *s = &drive->special;
705
706#ifdef DEBUG
707 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
708#endif
709 if (s->b.set_tune) {
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200710 ide_hwif_t *hwif = drive->hwif;
711 u8 req_pio = drive->tune_req;
712
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 s->b.set_tune = 0;
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200714
715 if (set_pio_mode_abuse(drive->hwif, req_pio)) {
Bartlomiej Zolnierkiewiczd393aa02007-10-20 00:32:36 +0200716
717 if (hwif->set_pio_mode == NULL)
718 return ide_stopped;
719
720 /*
721 * take ide_lock for drive->[no_]unmask/[no_]io_32bit
722 */
723 if (req_pio == 8 || req_pio == 9) {
724 unsigned long flags;
725
726 spin_lock_irqsave(&ide_lock, flags);
727 hwif->set_pio_mode(drive, req_pio);
728 spin_unlock_irqrestore(&ide_lock, flags);
729 } else
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200730 hwif->set_pio_mode(drive, req_pio);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200731 } else {
732 int keep_dma = drive->using_dma;
733
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200734 ide_set_pio(drive, req_pio);
735
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200736 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) {
737 if (keep_dma)
Bartlomiej Zolnierkiewicz4a546e02008-01-26 20:13:01 +0100738 ide_dma_on(drive);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200739 }
740 }
741
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 return ide_stopped;
743 } else {
744 if (drive->media == ide_disk)
745 return ide_disk_special(drive);
746
747 s->all = 0;
748 drive->mult_req = 0;
749 return ide_stopped;
750 }
751}
752
753void ide_map_sg(ide_drive_t *drive, struct request *rq)
754{
755 ide_hwif_t *hwif = drive->hwif;
756 struct scatterlist *sg = hwif->sg_table;
757
758 if (hwif->sg_mapped) /* needed by ide-scsi */
759 return;
760
Jens Axboe4aff5e22006-08-10 08:44:47 +0200761 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
763 } else {
764 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
765 hwif->sg_nents = 1;
766 }
767}
768
769EXPORT_SYMBOL_GPL(ide_map_sg);
770
771void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
772{
773 ide_hwif_t *hwif = drive->hwif;
774
775 hwif->nsect = hwif->nleft = rq->nr_sectors;
Jens Axboe55c16a72007-07-25 08:13:56 +0200776 hwif->cursg_ofs = 0;
777 hwif->cursg = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778}
779
780EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
781
782/**
783 * execute_drive_command - issue special drive command
Adrian Bunk338cec32005-09-10 00:26:54 -0700784 * @drive: the drive to issue the command on
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 * @rq: the request structure holding the command
786 *
787 * execute_drive_cmd() issues a special drive command, usually
788 * initiated by ioctl() from the external hdparm program. The
789 * command can be a drive command, drive task or taskfile
790 * operation. Weirdly you can call it with NULL to wait for
791 * all commands to finish. Don't do this as that is due to change
792 */
793
794static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
795 struct request *rq)
796{
797 ide_hwif_t *hwif = HWIF(drive);
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100798 ide_task_t *task = rq->special;
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100799
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100800 if (task) {
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100801 hwif->data_phase = task->data_phase;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802
803 switch (hwif->data_phase) {
804 case TASKFILE_MULTI_OUT:
805 case TASKFILE_OUT:
806 case TASKFILE_MULTI_IN:
807 case TASKFILE_IN:
808 ide_init_sg_cmd(drive, rq);
809 ide_map_sg(drive, rq);
810 default:
811 break;
812 }
813
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100814 return do_rw_taskfile(drive, task);
815 }
816
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817 /*
818 * NULL is actually a valid way of waiting for
819 * all current requests to be flushed from the queue.
820 */
821#ifdef DEBUG
822 printk("%s: DRIVE_CMD (null)\n", drive->name);
823#endif
824 ide_end_drive_cmd(drive,
825 hwif->INB(IDE_STATUS_REG),
826 hwif->INB(IDE_ERROR_REG));
827 return ide_stopped;
828}
829
Jens Axboead3cadd2006-06-13 08:46:57 +0200830static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
831{
Jens Axboec00895a2006-09-30 20:29:12 +0200832 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200833
834 if (blk_pm_suspend_request(rq) &&
835 pm->pm_step == ide_pm_state_start_suspend)
836 /* Mark drive blocked when starting the suspend sequence. */
837 drive->blocked = 1;
838 else if (blk_pm_resume_request(rq) &&
839 pm->pm_step == ide_pm_state_start_resume) {
840 /*
841 * The first thing we do on wakeup is to wait for BSY bit to
842 * go away (with a looong timeout) as a drive on this hwif may
843 * just be POSTing itself.
844 * We do that before even selecting as the "other" device on
845 * the bus may be broken enough to walk on our toes at this
846 * point.
847 */
848 int rc;
849#ifdef DEBUG_PM
850 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
851#endif
852 rc = ide_wait_not_busy(HWIF(drive), 35000);
853 if (rc)
854 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
855 SELECT_DRIVE(drive);
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +0100856 ide_set_irq(drive, 1);
Al Boldi178184b2006-06-26 00:26:13 -0700857 rc = ide_wait_not_busy(HWIF(drive), 100000);
Jens Axboead3cadd2006-06-13 08:46:57 +0200858 if (rc)
859 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
860 }
861}
862
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863/**
864 * start_request - start of I/O and command issuing for IDE
865 *
866 * start_request() initiates handling of a new I/O request. It
867 * accepts commands and I/O (read/write) requests. It also does
868 * the final remapping for weird stuff like EZDrive. Once
869 * device mapper can work sector level the EZDrive stuff can go away
870 *
871 * FIXME: this function needs a rename
872 */
873
874static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
875{
876 ide_startstop_t startstop;
877 sector_t block;
878
Jens Axboe4aff5e22006-08-10 08:44:47 +0200879 BUG_ON(!blk_rq_started(rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880
881#ifdef DEBUG
882 printk("%s: start_request: current=0x%08lx\n",
883 HWIF(drive)->name, (unsigned long) rq);
884#endif
885
886 /* bail early if we've exceeded max_failures */
887 if (drive->max_failures && (drive->failures > drive->max_failures)) {
Aristeu Rozanskib5e1a4e2008-01-25 22:17:04 +0100888 rq->cmd_flags |= REQ_FAILED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889 goto kill_rq;
890 }
891
892 block = rq->sector;
893 if (blk_fs_request(rq) &&
894 (drive->media == ide_disk || drive->media == ide_floppy)) {
895 block += drive->sect0;
896 }
897 /* Yecch - this will shift the entire interval,
898 possibly killing some innocent following sector */
899 if (block == 0 && drive->remap_0_to_1 == 1)
900 block = 1; /* redirect MBR access to EZ-Drive partn table */
901
Jens Axboead3cadd2006-06-13 08:46:57 +0200902 if (blk_pm_request(rq))
903 ide_check_pm_state(drive, rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700904
905 SELECT_DRIVE(drive);
906 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
907 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
908 return startstop;
909 }
910 if (!drive->special.all) {
911 ide_driver_t *drv;
912
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200913 /*
914 * We reset the drive so we need to issue a SETFEATURES.
915 * Do it _after_ do_special() restored device parameters.
916 */
917 if (drive->current_speed == 0xff)
918 ide_config_drive_speed(drive, drive->desired_speed);
919
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100920 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 return execute_drive_cmd(drive, rq);
922 else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200923 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924#ifdef DEBUG_PM
925 printk("%s: start_power_step(step: %d)\n",
926 drive->name, rq->pm->pm_step);
927#endif
928 startstop = ide_start_power_step(drive, rq);
929 if (startstop == ide_stopped &&
Jens Axboead3cadd2006-06-13 08:46:57 +0200930 pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 ide_complete_pm_request(drive, rq);
932 return startstop;
933 }
934
935 drv = *(ide_driver_t **)rq->rq_disk->private_data;
936 return drv->do_request(drive, rq, block);
937 }
938 return do_special(drive);
939kill_rq:
940 ide_kill_rq(drive, rq);
941 return ide_stopped;
942}
943
944/**
945 * ide_stall_queue - pause an IDE device
946 * @drive: drive to stall
947 * @timeout: time to stall for (jiffies)
948 *
949 * ide_stall_queue() can be used by a drive to give excess bandwidth back
950 * to the hwgroup by sleeping for timeout jiffies.
951 */
952
953void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
954{
955 if (timeout > WAIT_WORSTCASE)
956 timeout = WAIT_WORSTCASE;
957 drive->sleep = timeout + jiffies;
958 drive->sleeping = 1;
959}
960
961EXPORT_SYMBOL(ide_stall_queue);
962
963#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
964
965/**
966 * choose_drive - select a drive to service
967 * @hwgroup: hardware group to select on
968 *
969 * choose_drive() selects the next drive which will be serviced.
970 * This is necessary because the IDE layer can't issue commands
971 * to both drives on the same cable, unlike SCSI.
972 */
973
974static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
975{
976 ide_drive_t *drive, *best;
977
978repeat:
979 best = NULL;
980 drive = hwgroup->drive;
981
982 /*
983 * drive is doing pre-flush, ordered write, post-flush sequence. even
984 * though that is 3 requests, it must be seen as a single transaction.
985 * we must not preempt this drive until that is complete
986 */
987 if (blk_queue_flushing(drive->queue)) {
988 /*
989 * small race where queue could get replugged during
990 * the 3-request flush cycle, just yank the plug since
991 * we want it to finish asap
992 */
993 blk_remove_plug(drive->queue);
994 return drive;
995 }
996
997 do {
998 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
999 && !elv_queue_empty(drive->queue)) {
1000 if (!best
1001 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
1002 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
1003 {
1004 if (!blk_queue_plugged(drive->queue))
1005 best = drive;
1006 }
1007 }
1008 } while ((drive = drive->next) != hwgroup->drive);
1009 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1010 long t = (signed long)(WAKEUP(best) - jiffies);
1011 if (t >= WAIT_MIN_SLEEP) {
1012 /*
1013 * We *may* have some time to spare, but first let's see if
1014 * someone can potentially benefit from our nice mood today..
1015 */
1016 drive = best->next;
1017 do {
1018 if (!drive->sleeping
1019 && time_before(jiffies - best->service_time, WAKEUP(drive))
1020 && time_before(WAKEUP(drive), jiffies + t))
1021 {
1022 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1023 goto repeat;
1024 }
1025 } while ((drive = drive->next) != best);
1026 }
1027 }
1028 return best;
1029}
1030
1031/*
1032 * Issue a new request to a drive from hwgroup
1033 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1034 *
1035 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1036 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1037 * may have both interfaces in a single hwgroup to "serialize" access.
1038 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1039 * together into one hwgroup for serialized access.
1040 *
1041 * Note also that several hwgroups can end up sharing a single IRQ,
1042 * possibly along with many other devices. This is especially common in
1043 * PCI-based systems with off-board IDE controller cards.
1044 *
1045 * The IDE driver uses the single global ide_lock spinlock to protect
1046 * access to the request queues, and to protect the hwgroup->busy flag.
1047 *
1048 * The first thread into the driver for a particular hwgroup sets the
1049 * hwgroup->busy flag to indicate that this hwgroup is now active,
1050 * and then initiates processing of the top request from the request queue.
1051 *
1052 * Other threads attempting entry notice the busy setting, and will simply
1053 * queue their new requests and exit immediately. Note that hwgroup->busy
1054 * remains set even when the driver is merely awaiting the next interrupt.
1055 * Thus, the meaning is "this hwgroup is busy processing a request".
1056 *
1057 * When processing of a request completes, the completing thread or IRQ-handler
1058 * will start the next request from the queue. If no more work remains,
1059 * the driver will clear the hwgroup->busy flag and exit.
1060 *
1061 * The ide_lock (spinlock) is used to protect all access to the
1062 * hwgroup->busy flag, but is otherwise not needed for most processing in
1063 * the driver. This makes the driver much more friendlier to shared IRQs
1064 * than previous designs, while remaining 100% (?) SMP safe and capable.
1065 */
1066static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1067{
1068 ide_drive_t *drive;
1069 ide_hwif_t *hwif;
1070 struct request *rq;
1071 ide_startstop_t startstop;
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001072 int loops = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001073
1074 /* for atari only: POSSIBLY BROKEN HERE(?) */
1075 ide_get_lock(ide_intr, hwgroup);
1076
1077 /* caller must own ide_lock */
1078 BUG_ON(!irqs_disabled());
1079
1080 while (!hwgroup->busy) {
1081 hwgroup->busy = 1;
1082 drive = choose_drive(hwgroup);
1083 if (drive == NULL) {
1084 int sleeping = 0;
1085 unsigned long sleep = 0; /* shut up, gcc */
1086 hwgroup->rq = NULL;
1087 drive = hwgroup->drive;
1088 do {
1089 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1090 sleeping = 1;
1091 sleep = drive->sleep;
1092 }
1093 } while ((drive = drive->next) != hwgroup->drive);
1094 if (sleeping) {
1095 /*
1096 * Take a short snooze, and then wake up this hwgroup again.
1097 * This gives other hwgroups on the same a chance to
1098 * play fairly with us, just in case there are big differences
1099 * in relative throughputs.. don't want to hog the cpu too much.
1100 */
1101 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1102 sleep = jiffies + WAIT_MIN_SLEEP;
1103#if 1
1104 if (timer_pending(&hwgroup->timer))
1105 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1106#endif
1107 /* so that ide_timer_expiry knows what to do */
1108 hwgroup->sleeping = 1;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001109 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 mod_timer(&hwgroup->timer, sleep);
1111 /* we purposely leave hwgroup->busy==1
1112 * while sleeping */
1113 } else {
1114 /* Ugly, but how can we sleep for the lock
1115 * otherwise? perhaps from tq_disk?
1116 */
1117
1118 /* for atari only */
1119 ide_release_lock();
1120 hwgroup->busy = 0;
1121 }
1122
1123 /* no more work for this hwgroup (for now) */
1124 return;
1125 }
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001126 again:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127 hwif = HWIF(drive);
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +01001128 if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) {
Bartlomiej Zolnierkiewicz7299a392008-01-25 22:17:14 +01001129 /*
1130 * set nIEN for previous hwif, drives in the
1131 * quirk_list may not like intr setups/cleanups
1132 */
1133 if (drive->quirk_list != 1)
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +01001134 ide_set_irq(drive, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 }
1136 hwgroup->hwif = hwif;
1137 hwgroup->drive = drive;
1138 drive->sleeping = 0;
1139 drive->service_start = jiffies;
1140
1141 if (blk_queue_plugged(drive->queue)) {
1142 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1143 break;
1144 }
1145
1146 /*
1147 * we know that the queue isn't empty, but this can happen
1148 * if the q->prep_rq_fn() decides to kill a request
1149 */
1150 rq = elv_next_request(drive->queue);
1151 if (!rq) {
1152 hwgroup->busy = 0;
1153 break;
1154 }
1155
1156 /*
1157 * Sanity: don't accept a request that isn't a PM request
1158 * if we are currently power managed. This is very important as
1159 * blk_stop_queue() doesn't prevent the elv_next_request()
1160 * above to return us whatever is in the queue. Since we call
1161 * ide_do_request() ourselves, we end up taking requests while
1162 * the queue is blocked...
1163 *
1164 * We let requests forced at head of queue with ide-preempt
1165 * though. I hope that doesn't happen too much, hopefully not
1166 * unless the subdriver triggers such a thing in its own PM
1167 * state machine.
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001168 *
1169 * We count how many times we loop here to make sure we service
1170 * all drives in the hwgroup without looping for ever
Linus Torvalds1da177e2005-04-16 15:20:36 -07001171 */
Jens Axboe4aff5e22006-08-10 08:44:47 +02001172 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) {
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001173 drive = drive->next ? drive->next : hwgroup->drive;
1174 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1175 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176 /* We clear busy, there should be no pending ATA command at this point. */
1177 hwgroup->busy = 0;
1178 break;
1179 }
1180
1181 hwgroup->rq = rq;
1182
1183 /*
1184 * Some systems have trouble with IDE IRQs arriving while
1185 * the driver is still setting things up. So, here we disable
1186 * the IRQ used by this interface while the request is being started.
1187 * This may look bad at first, but pretty much the same thing
1188 * happens anyway when any interrupt comes in, IDE or otherwise
1189 * -- the kernel masks the IRQ while it is being handled.
1190 */
1191 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1192 disable_irq_nosync(hwif->irq);
1193 spin_unlock(&ide_lock);
Ingo Molnar366c7f52006-07-03 00:25:25 -07001194 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001195 /* allow other IRQs while we start this request */
1196 startstop = start_request(drive, rq);
1197 spin_lock_irq(&ide_lock);
1198 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1199 enable_irq(hwif->irq);
1200 if (startstop == ide_stopped)
1201 hwgroup->busy = 0;
1202 }
1203}
1204
1205/*
1206 * Passes the stuff to ide_do_request
1207 */
Jens Axboe165125e2007-07-24 09:28:11 +02001208void do_ide_request(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001209{
1210 ide_drive_t *drive = q->queuedata;
1211
1212 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1213}
1214
1215/*
1216 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1217 * retry the current request in pio mode instead of risking tossing it
1218 * all away
1219 */
1220static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1221{
1222 ide_hwif_t *hwif = HWIF(drive);
1223 struct request *rq;
1224 ide_startstop_t ret = ide_stopped;
1225
1226 /*
1227 * end current dma transaction
1228 */
1229
1230 if (error < 0) {
1231 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1232 (void)HWIF(drive)->ide_dma_end(drive);
1233 ret = ide_error(drive, "dma timeout error",
1234 hwif->INB(IDE_STATUS_REG));
1235 } else {
1236 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
Sergei Shtylyovc283f5d2007-07-09 23:17:54 +02001237 hwif->dma_timeout(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 }
1239
1240 /*
1241 * disable dma for now, but remember that we did so because of
1242 * a timeout -- we'll reenable after we finish this next request
1243 * (or rather the first chunk of it) in pio.
1244 */
1245 drive->retry_pio++;
1246 drive->state = DMA_PIO_RETRY;
Bartlomiej Zolnierkiewicz4a546e02008-01-26 20:13:01 +01001247 ide_dma_off_quietly(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248
1249 /*
1250 * un-busy drive etc (hwgroup->busy is cleared on return) and
1251 * make sure request is sane
1252 */
1253 rq = HWGROUP(drive)->rq;
Hua Zhongce42f192006-10-03 01:14:15 -07001254
1255 if (!rq)
1256 goto out;
1257
Linus Torvalds1da177e2005-04-16 15:20:36 -07001258 HWGROUP(drive)->rq = NULL;
1259
1260 rq->errors = 0;
1261
1262 if (!rq->bio)
1263 goto out;
1264
1265 rq->sector = rq->bio->bi_sector;
1266 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1267 rq->hard_cur_sectors = rq->current_nr_sectors;
1268 rq->buffer = bio_data(rq->bio);
1269out:
1270 return ret;
1271}
1272
1273/**
1274 * ide_timer_expiry - handle lack of an IDE interrupt
1275 * @data: timer callback magic (hwgroup)
1276 *
1277 * An IDE command has timed out before the expected drive return
1278 * occurred. At this point we attempt to clean up the current
1279 * mess. If the current handler includes an expiry handler then
1280 * we invoke the expiry handler, and providing it is happy the
1281 * work is done. If that fails we apply generic recovery rules
1282 * invoking the handler and checking the drive DMA status. We
1283 * have an excessively incestuous relationship with the DMA
1284 * logic that wants cleaning up.
1285 */
1286
1287void ide_timer_expiry (unsigned long data)
1288{
1289 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1290 ide_handler_t *handler;
1291 ide_expiry_t *expiry;
1292 unsigned long flags;
1293 unsigned long wait = -1;
1294
1295 spin_lock_irqsave(&ide_lock, flags);
1296
Suleiman Souhlal23450312007-04-10 22:38:37 +02001297 if (((handler = hwgroup->handler) == NULL) ||
1298 (hwgroup->req_gen != hwgroup->req_gen_timer)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 /*
1300 * Either a marginal timeout occurred
1301 * (got the interrupt just as timer expired),
1302 * or we were "sleeping" to give other devices a chance.
1303 * Either way, we don't really want to complain about anything.
1304 */
1305 if (hwgroup->sleeping) {
1306 hwgroup->sleeping = 0;
1307 hwgroup->busy = 0;
1308 }
1309 } else {
1310 ide_drive_t *drive = hwgroup->drive;
1311 if (!drive) {
1312 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1313 hwgroup->handler = NULL;
1314 } else {
1315 ide_hwif_t *hwif;
1316 ide_startstop_t startstop = ide_stopped;
1317 if (!hwgroup->busy) {
1318 hwgroup->busy = 1; /* paranoia */
1319 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1320 }
1321 if ((expiry = hwgroup->expiry) != NULL) {
1322 /* continue */
1323 if ((wait = expiry(drive)) > 0) {
1324 /* reset timer */
1325 hwgroup->timer.expires = jiffies + wait;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001326 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327 add_timer(&hwgroup->timer);
1328 spin_unlock_irqrestore(&ide_lock, flags);
1329 return;
1330 }
1331 }
1332 hwgroup->handler = NULL;
1333 /*
1334 * We need to simulate a real interrupt when invoking
1335 * the handler() function, which means we need to
1336 * globally mask the specific IRQ:
1337 */
1338 spin_unlock(&ide_lock);
1339 hwif = HWIF(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340 /* disable_irq_nosync ?? */
1341 disable_irq(hwif->irq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342 /* local CPU only,
1343 * as if we were handling an interrupt */
1344 local_irq_disable();
1345 if (hwgroup->polling) {
1346 startstop = handler(drive);
1347 } else if (drive_is_ready(drive)) {
1348 if (drive->waiting_for_dma)
Sergei Shtylyov841d2a92007-07-09 23:17:54 +02001349 hwgroup->hwif->dma_lost_irq(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350 (void)ide_ack_intr(hwif);
1351 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1352 startstop = handler(drive);
1353 } else {
1354 if (drive->waiting_for_dma) {
1355 startstop = ide_dma_timeout_retry(drive, wait);
1356 } else
1357 startstop =
1358 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG));
1359 }
1360 drive->service_time = jiffies - drive->service_start;
1361 spin_lock_irq(&ide_lock);
1362 enable_irq(hwif->irq);
1363 if (startstop == ide_stopped)
1364 hwgroup->busy = 0;
1365 }
1366 }
1367 ide_do_request(hwgroup, IDE_NO_IRQ);
1368 spin_unlock_irqrestore(&ide_lock, flags);
1369}
1370
1371/**
1372 * unexpected_intr - handle an unexpected IDE interrupt
1373 * @irq: interrupt line
1374 * @hwgroup: hwgroup being processed
1375 *
1376 * There's nothing really useful we can do with an unexpected interrupt,
1377 * other than reading the status register (to clear it), and logging it.
1378 * There should be no way that an irq can happen before we're ready for it,
1379 * so we needn't worry much about losing an "important" interrupt here.
1380 *
1381 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1382 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1383 * looks "good", we just ignore the interrupt completely.
1384 *
1385 * This routine assumes __cli() is in effect when called.
1386 *
1387 * If an unexpected interrupt happens on irq15 while we are handling irq14
1388 * and if the two interfaces are "serialized" (CMD640), then it looks like
1389 * we could screw up by interfering with a new request being set up for
1390 * irq15.
1391 *
1392 * In reality, this is a non-issue. The new command is not sent unless
1393 * the drive is ready to accept one, in which case we know the drive is
1394 * not trying to interrupt us. And ide_set_handler() is always invoked
1395 * before completing the issuance of any new drive command, so we will not
1396 * be accidentally invoked as a result of any valid command completion
1397 * interrupt.
1398 *
1399 * Note that we must walk the entire hwgroup here. We know which hwif
1400 * is doing the current command, but we don't know which hwif burped
1401 * mysteriously.
1402 */
1403
1404static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1405{
1406 u8 stat;
1407 ide_hwif_t *hwif = hwgroup->hwif;
1408
1409 /*
1410 * handle the unexpected interrupt
1411 */
1412 do {
1413 if (hwif->irq == irq) {
1414 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1415 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1416 /* Try to not flood the console with msgs */
1417 static unsigned long last_msgtime, count;
1418 ++count;
1419 if (time_after(jiffies, last_msgtime + HZ)) {
1420 last_msgtime = jiffies;
1421 printk(KERN_ERR "%s%s: unexpected interrupt, "
1422 "status=0x%02x, count=%ld\n",
1423 hwif->name,
1424 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1425 }
1426 }
1427 }
1428 } while ((hwif = hwif->next) != hwgroup->hwif);
1429}
1430
1431/**
1432 * ide_intr - default IDE interrupt handler
1433 * @irq: interrupt number
1434 * @dev_id: hwif group
1435 * @regs: unused weirdness from the kernel irq layer
1436 *
1437 * This is the default IRQ handler for the IDE layer. You should
1438 * not need to override it. If you do be aware it is subtle in
1439 * places
1440 *
1441 * hwgroup->hwif is the interface in the group currently performing
1442 * a command. hwgroup->drive is the drive and hwgroup->handler is
1443 * the IRQ handler to call. As we issue a command the handlers
1444 * step through multiple states, reassigning the handler to the
1445 * next step in the process. Unlike a smart SCSI controller IDE
1446 * expects the main processor to sequence the various transfer
1447 * stages. We also manage a poll timer to catch up with most
1448 * timeout situations. There are still a few where the handlers
1449 * don't ever decide to give up.
1450 *
1451 * The handler eventually returns ide_stopped to indicate the
1452 * request completed. At this point we issue the next request
1453 * on the hwgroup and the process begins again.
1454 */
1455
David Howells7d12e782006-10-05 14:55:46 +01001456irqreturn_t ide_intr (int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457{
1458 unsigned long flags;
1459 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1460 ide_hwif_t *hwif;
1461 ide_drive_t *drive;
1462 ide_handler_t *handler;
1463 ide_startstop_t startstop;
1464
1465 spin_lock_irqsave(&ide_lock, flags);
1466 hwif = hwgroup->hwif;
1467
1468 if (!ide_ack_intr(hwif)) {
1469 spin_unlock_irqrestore(&ide_lock, flags);
1470 return IRQ_NONE;
1471 }
1472
1473 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1474 /*
1475 * Not expecting an interrupt from this drive.
1476 * That means this could be:
1477 * (1) an interrupt from another PCI device
1478 * sharing the same PCI INT# as us.
1479 * or (2) a drive just entered sleep or standby mode,
1480 * and is interrupting to let us know.
1481 * or (3) a spurious interrupt of unknown origin.
1482 *
1483 * For PCI, we cannot tell the difference,
1484 * so in that case we just ignore it and hope it goes away.
1485 *
1486 * FIXME: unexpected_intr should be hwif-> then we can
1487 * remove all the ifdef PCI crap
1488 */
1489#ifdef CONFIG_BLK_DEV_IDEPCI
1490 if (hwif->pci_dev && !hwif->pci_dev->vendor)
1491#endif /* CONFIG_BLK_DEV_IDEPCI */
1492 {
1493 /*
1494 * Probably not a shared PCI interrupt,
1495 * so we can safely try to do something about it:
1496 */
1497 unexpected_intr(irq, hwgroup);
1498#ifdef CONFIG_BLK_DEV_IDEPCI
1499 } else {
1500 /*
1501 * Whack the status register, just in case
1502 * we have a leftover pending IRQ.
1503 */
1504 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1505#endif /* CONFIG_BLK_DEV_IDEPCI */
1506 }
1507 spin_unlock_irqrestore(&ide_lock, flags);
1508 return IRQ_NONE;
1509 }
1510 drive = hwgroup->drive;
1511 if (!drive) {
1512 /*
1513 * This should NEVER happen, and there isn't much
1514 * we could do about it here.
1515 *
1516 * [Note - this can occur if the drive is hot unplugged]
1517 */
1518 spin_unlock_irqrestore(&ide_lock, flags);
1519 return IRQ_HANDLED;
1520 }
1521 if (!drive_is_ready(drive)) {
1522 /*
1523 * This happens regularly when we share a PCI IRQ with
1524 * another device. Unfortunately, it can also happen
1525 * with some buggy drives that trigger the IRQ before
1526 * their status register is up to date. Hopefully we have
1527 * enough advance overhead that the latter isn't a problem.
1528 */
1529 spin_unlock_irqrestore(&ide_lock, flags);
1530 return IRQ_NONE;
1531 }
1532 if (!hwgroup->busy) {
1533 hwgroup->busy = 1; /* paranoia */
1534 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1535 }
1536 hwgroup->handler = NULL;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001537 hwgroup->req_gen++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001538 del_timer(&hwgroup->timer);
1539 spin_unlock(&ide_lock);
1540
Albert Leef0dd8712007-02-17 02:40:21 +01001541 /* Some controllers might set DMA INTR no matter DMA or PIO;
1542 * bmdma status might need to be cleared even for
1543 * PIO interrupts to prevent spurious/lost irq.
1544 */
1545 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma))
1546 /* ide_dma_end() needs bmdma status for error checking.
1547 * So, skip clearing bmdma status here and leave it
1548 * to ide_dma_end() if this is dma interrupt.
1549 */
1550 hwif->ide_dma_clear_irq(drive);
1551
Linus Torvalds1da177e2005-04-16 15:20:36 -07001552 if (drive->unmask)
Ingo Molnar366c7f52006-07-03 00:25:25 -07001553 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001554 /* service this interrupt, may set handler for next interrupt */
1555 startstop = handler(drive);
1556 spin_lock_irq(&ide_lock);
1557
1558 /*
1559 * Note that handler() may have set things up for another
1560 * interrupt to occur soon, but it cannot happen until
1561 * we exit from this routine, because it will be the
1562 * same irq as is currently being serviced here, and Linux
1563 * won't allow another of the same (on any CPU) until we return.
1564 */
1565 drive->service_time = jiffies - drive->service_start;
1566 if (startstop == ide_stopped) {
1567 if (hwgroup->handler == NULL) { /* paranoia */
1568 hwgroup->busy = 0;
1569 ide_do_request(hwgroup, hwif->irq);
1570 } else {
1571 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1572 "on exit\n", drive->name);
1573 }
1574 }
1575 spin_unlock_irqrestore(&ide_lock, flags);
1576 return IRQ_HANDLED;
1577}
1578
1579/**
1580 * ide_init_drive_cmd - initialize a drive command request
1581 * @rq: request object
1582 *
1583 * Initialize a request before we fill it in and send it down to
1584 * ide_do_drive_cmd. Commands must be set up by this function. Right
1585 * now it doesn't do a lot, but if that changes abusers will have a
Andreas Mohrd6e05ed2006-06-26 18:35:02 +02001586 * nasty surprise.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001587 */
1588
1589void ide_init_drive_cmd (struct request *rq)
1590{
1591 memset(rq, 0, sizeof(*rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001592 rq->ref_count = 1;
1593}
1594
1595EXPORT_SYMBOL(ide_init_drive_cmd);
1596
1597/**
1598 * ide_do_drive_cmd - issue IDE special command
1599 * @drive: device to issue command
1600 * @rq: request to issue
1601 * @action: action for processing
1602 *
1603 * This function issues a special IDE device request
1604 * onto the request queue.
1605 *
1606 * If action is ide_wait, then the rq is queued at the end of the
1607 * request queue, and the function sleeps until it has been processed.
1608 * This is for use when invoked from an ioctl handler.
1609 *
1610 * If action is ide_preempt, then the rq is queued at the head of
1611 * the request queue, displacing the currently-being-processed
1612 * request and this function returns immediately without waiting
1613 * for the new rq to be completed. This is VERY DANGEROUS, and is
1614 * intended for careful use by the ATAPI tape/cdrom driver code.
1615 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001616 * If action is ide_end, then the rq is queued at the end of the
1617 * request queue, and the function returns immediately without waiting
1618 * for the new rq to be completed. This is again intended for careful
1619 * use by the ATAPI tape/cdrom driver code.
1620 */
1621
1622int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1623{
1624 unsigned long flags;
1625 ide_hwgroup_t *hwgroup = HWGROUP(drive);
Ingo Molnar60be6b92006-07-03 00:25:26 -07001626 DECLARE_COMPLETION_ONSTACK(wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001627 int where = ELEVATOR_INSERT_BACK, err;
1628 int must_wait = (action == ide_wait || action == ide_head_wait);
1629
1630 rq->errors = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001631
1632 /*
1633 * we need to hold an extra reference to request for safe inspection
1634 * after completion
1635 */
1636 if (must_wait) {
1637 rq->ref_count++;
Jens Axboec00895a2006-09-30 20:29:12 +02001638 rq->end_io_data = &wait;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001639 rq->end_io = blk_end_sync_rq;
1640 }
1641
1642 spin_lock_irqsave(&ide_lock, flags);
1643 if (action == ide_preempt)
1644 hwgroup->rq = NULL;
1645 if (action == ide_preempt || action == ide_head_wait) {
1646 where = ELEVATOR_INSERT_FRONT;
Jens Axboe4aff5e22006-08-10 08:44:47 +02001647 rq->cmd_flags |= REQ_PREEMPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001648 }
1649 __elv_add_request(drive->queue, rq, where, 0);
1650 ide_do_request(hwgroup, IDE_NO_IRQ);
1651 spin_unlock_irqrestore(&ide_lock, flags);
1652
1653 err = 0;
1654 if (must_wait) {
1655 wait_for_completion(&wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001656 if (rq->errors)
1657 err = -EIO;
1658
1659 blk_put_request(rq);
1660 }
1661
1662 return err;
1663}
1664
1665EXPORT_SYMBOL(ide_do_drive_cmd);
Bartlomiej Zolnierkiewicz2fc57382008-01-25 22:17:13 +01001666
1667void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma)
1668{
1669 ide_task_t task;
1670
1671 memset(&task, 0, sizeof(task));
1672 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
1673 IDE_TFLAG_OUT_FEATURE | tf_flags;
1674 task.tf.feature = dma; /* Use PIO/DMA */
1675 task.tf.lbam = bcount & 0xff;
1676 task.tf.lbah = (bcount >> 8) & 0xff;
1677
1678 ide_tf_load(drive, &task);
1679}
1680
1681EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load);