blob: c22a337ced4eaf1b9b42e9f1bdcfca6dae6ef289 [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 Zolnierkiewicz5e37bdc2008-04-26 22:25:24 +0200221 if (drive->hwif->dma_ops == 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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298/**
299 * ide_end_drive_cmd - end an explicit drive command
300 * @drive: command
301 * @stat: status bits
302 * @err: error bits
303 *
304 * Clean up after success/failure of an explicit drive command.
305 * These get thrown onto the queue so they are synchronized with
306 * real I/O operations on the drive.
307 *
308 * In LBA48 mode we have to read the register set twice to get
309 * all the extra information out.
310 */
311
312void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
313{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 unsigned long flags;
315 struct request *rq;
316
317 spin_lock_irqsave(&ide_lock, flags);
318 rq = HWGROUP(drive)->rq;
319 spin_unlock_irqrestore(&ide_lock, flags);
320
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100321 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
Bartlomiej Zolnierkiewicz395d8ef2008-02-11 00:32:14 +0100322 ide_task_t *task = (ide_task_t *)rq->special;
323
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 if (rq->errors == 0)
Bartlomiej Zolnierkiewicz395d8ef2008-02-11 00:32:14 +0100325 rq->errors = !OK_STAT(stat, READY_STAT, BAD_STAT);
326
327 if (task) {
328 struct ide_taskfile *tf = &task->tf;
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100329
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100330 tf->error = err;
Bartlomiej Zolnierkiewicz650d8412008-01-25 22:17:06 +0100331 tf->status = stat;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332
Bartlomiej Zolnierkiewicz94cd5b62008-04-28 23:44:40 +0200333 drive->hwif->tf_read(drive, task);
Bartlomiej Zolnierkiewicz395d8ef2008-02-11 00:32:14 +0100334
335 if (task->tf_flags & IDE_TFLAG_DYN)
336 kfree(task);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337 }
338 } else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200339 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340#ifdef DEBUG_PM
341 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
342 drive->name, rq->pm->pm_step, stat, err);
343#endif
344 ide_complete_power_step(drive, rq, stat, err);
Jens Axboead3cadd2006-06-13 08:46:57 +0200345 if (pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 ide_complete_pm_request(drive, rq);
347 return;
348 }
349
350 spin_lock_irqsave(&ide_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 HWGROUP(drive)->rq = NULL;
352 rq->errors = err;
Kiyoshi Ueda3b0e0442008-02-11 00:32:11 +0100353 if (unlikely(__blk_end_request(rq, (rq->errors ? -EIO : 0),
354 blk_rq_bytes(rq))))
Kiyoshi Ueda5e36bb62008-01-28 10:34:20 +0100355 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 spin_unlock_irqrestore(&ide_lock, flags);
357}
358
359EXPORT_SYMBOL(ide_end_drive_cmd);
360
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
362{
363 if (rq->rq_disk) {
364 ide_driver_t *drv;
365
366 drv = *(ide_driver_t **)rq->rq_disk->private_data;
367 drv->end_request(drive, 0, 0);
368 } else
369 ide_end_request(drive, 0, 0);
370}
371
372static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
373{
374 ide_hwif_t *hwif = drive->hwif;
375
376 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
377 /* other bits are useless when BUSY */
378 rq->errors |= ERROR_RESET;
379 } else if (stat & ERR_STAT) {
380 /* err has different meaning on cdrom and tape */
381 if (err == ABRT_ERR) {
382 if (drive->select.b.lba &&
383 /* some newer drives don't support WIN_SPECIFY */
Bartlomiej Zolnierkiewicz4c3032d2008-04-27 15:38:32 +0200384 hwif->INB(hwif->io_ports.command_addr) ==
Bartlomiej Zolnierkiewicz23579a22008-04-18 00:46:26 +0200385 WIN_SPECIFY)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700386 return ide_stopped;
387 } else if ((err & BAD_CRC) == BAD_CRC) {
388 /* UDMA crc error, just retry the operation */
389 drive->crc_count++;
390 } else if (err & (BBD_ERR | ECC_ERR)) {
391 /* retries won't help these */
392 rq->errors = ERROR_MAX;
393 } else if (err & TRK0_ERR) {
394 /* help it find track zero */
395 rq->errors |= ERROR_RECAL;
396 }
397 }
398
Bartlomiej Zolnierkiewiczed67b922007-10-19 00:30:10 +0200399 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ &&
Bartlomiej Zolnierkiewicz57279a72008-07-15 21:21:47 +0200400 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) {
401 int nsect = drive->mult_count ? drive->mult_count : 1;
402
403 ide_pad_transfer(drive, READ, nsect * SECTOR_SIZE);
404 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200406 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 ide_kill_rq(drive, rq);
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200408 return ide_stopped;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409 }
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200410
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +0100411 if (ide_read_status(drive) & (BUSY_STAT | DRQ_STAT))
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200412 rq->errors |= ERROR_RESET;
413
414 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
415 ++rq->errors;
416 return ide_do_reset(drive);
417 }
418
419 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
420 drive->special.b.recalibrate = 1;
421
422 ++rq->errors;
423
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 return ide_stopped;
425}
426
427static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
428{
429 ide_hwif_t *hwif = drive->hwif;
430
431 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
432 /* other bits are useless when BUSY */
433 rq->errors |= ERROR_RESET;
434 } else {
435 /* add decoding error stuff */
436 }
437
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +0100438 if (ide_read_status(drive) & (BUSY_STAT | DRQ_STAT))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439 /* force an abort */
Bartlomiej Zolnierkiewicz32b3fe42008-04-28 23:44:38 +0200440 hwif->OUTBSYNC(drive, WIN_IDLEIMMEDIATE,
441 hwif->io_ports.command_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442
443 if (rq->errors >= ERROR_MAX) {
444 ide_kill_rq(drive, rq);
445 } else {
446 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
447 ++rq->errors;
448 return ide_do_reset(drive);
449 }
450 ++rq->errors;
451 }
452
453 return ide_stopped;
454}
455
456ide_startstop_t
457__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
458{
459 if (drive->media == ide_disk)
460 return ide_ata_error(drive, rq, stat, err);
461 return ide_atapi_error(drive, rq, stat, err);
462}
463
464EXPORT_SYMBOL_GPL(__ide_error);
465
466/**
467 * ide_error - handle an error on the IDE
468 * @drive: drive the error occurred on
469 * @msg: message to report
470 * @stat: status bits
471 *
472 * ide_error() takes action based on the error returned by the drive.
473 * For normal I/O that may well include retries. We deal with
474 * both new-style (taskfile) and old style command handling here.
475 * In the case of taskfile command handling there is work left to
476 * do
477 */
478
479ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
480{
481 struct request *rq;
482 u8 err;
483
484 err = ide_dump_status(drive, msg, stat);
485
486 if ((rq = HWGROUP(drive)->rq) == NULL)
487 return ide_stopped;
488
489 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200490 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 rq->errors = 1;
492 ide_end_drive_cmd(drive, stat, err);
493 return ide_stopped;
494 }
495
496 if (rq->rq_disk) {
497 ide_driver_t *drv;
498
499 drv = *(ide_driver_t **)rq->rq_disk->private_data;
500 return drv->error(drive, rq, stat, err);
501 } else
502 return __ide_error(drive, rq, stat, err);
503}
504
505EXPORT_SYMBOL_GPL(ide_error);
506
507ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
508{
509 if (drive->media != ide_disk)
510 rq->errors |= ERROR_RESET;
511
512 ide_kill_rq(drive, rq);
513
514 return ide_stopped;
515}
516
517EXPORT_SYMBOL_GPL(__ide_abort);
518
519/**
Adrian Bunk338cec32005-09-10 00:26:54 -0700520 * ide_abort - abort pending IDE operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521 * @drive: drive the error occurred on
522 * @msg: message to report
523 *
524 * ide_abort kills and cleans up when we are about to do a
525 * host initiated reset on active commands. Longer term we
526 * want handlers to have sensible abort handling themselves
527 *
528 * This differs fundamentally from ide_error because in
529 * this case the command is doing just fine when we
530 * blow it away.
531 */
532
533ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
534{
535 struct request *rq;
536
537 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
538 return ide_stopped;
539
540 /* retry only "normal" I/O: */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200541 if (!blk_fs_request(rq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 rq->errors = 1;
543 ide_end_drive_cmd(drive, BUSY_STAT, 0);
544 return ide_stopped;
545 }
546
547 if (rq->rq_disk) {
548 ide_driver_t *drv;
549
550 drv = *(ide_driver_t **)rq->rq_disk->private_data;
551 return drv->abort(drive, rq);
552 } else
553 return __ide_abort(drive, rq);
554}
555
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100556static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100558 tf->nsect = drive->sect;
559 tf->lbal = drive->sect;
560 tf->lbam = drive->cyl;
561 tf->lbah = drive->cyl >> 8;
562 tf->device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA;
563 tf->command = WIN_SPECIFY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564}
565
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100566static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100568 tf->nsect = drive->sect;
569 tf->command = WIN_RESTORE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570}
571
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100572static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573{
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100574 tf->nsect = drive->mult_req;
575 tf->command = WIN_SETMULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576}
577
578static ide_startstop_t ide_disk_special(ide_drive_t *drive)
579{
580 special_t *s = &drive->special;
581 ide_task_t args;
582
583 memset(&args, 0, sizeof(ide_task_t));
Bartlomiej Zolnierkiewiczac026ff2008-01-25 22:17:14 +0100584 args.data_phase = TASKFILE_NO_DATA;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585
586 if (s->b.set_geometry) {
587 s->b.set_geometry = 0;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100588 ide_tf_set_specify_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 } else if (s->b.recalibrate) {
590 s->b.recalibrate = 0;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100591 ide_tf_set_restore_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592 } else if (s->b.set_multmode) {
593 s->b.set_multmode = 0;
594 if (drive->mult_req > drive->id->max_multsect)
595 drive->mult_req = drive->id->max_multsect;
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100596 ide_tf_set_setmult_cmd(drive, &args.tf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 } else if (s->all) {
598 int special = s->all;
599 s->all = 0;
600 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
601 return ide_stopped;
602 }
603
Bartlomiej Zolnierkiewicz657cc1a2008-01-26 20:13:10 +0100604 args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE |
Bartlomiej Zolnierkiewicz57d73662008-01-25 22:17:16 +0100605 IDE_TFLAG_CUSTOM_HANDLER;
Bartlomiej Zolnierkiewicz74095a92008-01-25 22:17:07 +0100606
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 do_rw_taskfile(drive, &args);
608
609 return ide_started;
610}
611
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200612/*
613 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
614 */
615static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio)
616{
617 switch (req_pio) {
618 case 202:
619 case 201:
620 case 200:
621 case 102:
622 case 101:
623 case 100:
624 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0;
625 case 9:
626 case 8:
627 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0;
628 case 7:
629 case 6:
630 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0;
631 default:
632 return 0;
633 }
634}
635
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636/**
637 * do_special - issue some special commands
638 * @drive: drive the command is for
639 *
640 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
641 * commands to a drive. It used to do much more, but has been scaled
642 * back.
643 */
644
645static ide_startstop_t do_special (ide_drive_t *drive)
646{
647 special_t *s = &drive->special;
648
649#ifdef DEBUG
650 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
651#endif
652 if (s->b.set_tune) {
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200653 ide_hwif_t *hwif = drive->hwif;
Bartlomiej Zolnierkiewiczac95bee2008-04-26 22:25:14 +0200654 const struct ide_port_ops *port_ops = hwif->port_ops;
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200655 u8 req_pio = drive->tune_req;
656
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 s->b.set_tune = 0;
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200658
659 if (set_pio_mode_abuse(drive->hwif, req_pio)) {
Bartlomiej Zolnierkiewiczd393aa02007-10-20 00:32:36 +0200660 /*
661 * take ide_lock for drive->[no_]unmask/[no_]io_32bit
662 */
663 if (req_pio == 8 || req_pio == 9) {
664 unsigned long flags;
665
666 spin_lock_irqsave(&ide_lock, flags);
Bartlomiej Zolnierkiewiczac95bee2008-04-26 22:25:14 +0200667 port_ops->set_pio_mode(drive, req_pio);
Bartlomiej Zolnierkiewiczd393aa02007-10-20 00:32:36 +0200668 spin_unlock_irqrestore(&ide_lock, flags);
669 } else
Bartlomiej Zolnierkiewiczac95bee2008-04-26 22:25:14 +0200670 port_ops->set_pio_mode(drive, req_pio);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200671 } else {
672 int keep_dma = drive->using_dma;
673
Bartlomiej Zolnierkiewicz26bcb872007-10-11 23:54:00 +0200674 ide_set_pio(drive, req_pio);
675
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200676 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) {
677 if (keep_dma)
Bartlomiej Zolnierkiewicz4a546e02008-01-26 20:13:01 +0100678 ide_dma_on(drive);
Bartlomiej Zolnierkiewiczaedea592007-10-13 17:47:50 +0200679 }
680 }
681
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 return ide_stopped;
683 } else {
684 if (drive->media == ide_disk)
685 return ide_disk_special(drive);
686
687 s->all = 0;
688 drive->mult_req = 0;
689 return ide_stopped;
690 }
691}
692
693void ide_map_sg(ide_drive_t *drive, struct request *rq)
694{
695 ide_hwif_t *hwif = drive->hwif;
696 struct scatterlist *sg = hwif->sg_table;
697
698 if (hwif->sg_mapped) /* needed by ide-scsi */
699 return;
700
Jens Axboe4aff5e22006-08-10 08:44:47 +0200701 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
703 } else {
704 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
705 hwif->sg_nents = 1;
706 }
707}
708
709EXPORT_SYMBOL_GPL(ide_map_sg);
710
711void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
712{
713 ide_hwif_t *hwif = drive->hwif;
714
715 hwif->nsect = hwif->nleft = rq->nr_sectors;
Jens Axboe55c16a72007-07-25 08:13:56 +0200716 hwif->cursg_ofs = 0;
717 hwif->cursg = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718}
719
720EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
721
722/**
723 * execute_drive_command - issue special drive command
Adrian Bunk338cec32005-09-10 00:26:54 -0700724 * @drive: the drive to issue the command on
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 * @rq: the request structure holding the command
726 *
727 * execute_drive_cmd() issues a special drive command, usually
728 * initiated by ioctl() from the external hdparm program. The
729 * command can be a drive command, drive task or taskfile
730 * operation. Weirdly you can call it with NULL to wait for
731 * all commands to finish. Don't do this as that is due to change
732 */
733
734static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
735 struct request *rq)
736{
737 ide_hwif_t *hwif = HWIF(drive);
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100738 ide_task_t *task = rq->special;
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100739
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100740 if (task) {
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100741 hwif->data_phase = task->data_phase;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742
743 switch (hwif->data_phase) {
744 case TASKFILE_MULTI_OUT:
745 case TASKFILE_OUT:
746 case TASKFILE_MULTI_IN:
747 case TASKFILE_IN:
748 ide_init_sg_cmd(drive, rq);
749 ide_map_sg(drive, rq);
750 default:
751 break;
752 }
753
Bartlomiej Zolnierkiewicz21d535c2008-01-25 22:17:09 +0100754 return do_rw_taskfile(drive, task);
755 }
756
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 /*
758 * NULL is actually a valid way of waiting for
759 * all current requests to be flushed from the queue.
760 */
761#ifdef DEBUG
762 printk("%s: DRIVE_CMD (null)\n", drive->name);
763#endif
Bartlomiej Zolnierkiewicz64a57fe2008-02-06 02:57:51 +0100764 ide_end_drive_cmd(drive, ide_read_status(drive), ide_read_error(drive));
765
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 return ide_stopped;
767}
768
Jens Axboead3cadd2006-06-13 08:46:57 +0200769static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
770{
Jens Axboec00895a2006-09-30 20:29:12 +0200771 struct request_pm_state *pm = rq->data;
Jens Axboead3cadd2006-06-13 08:46:57 +0200772
773 if (blk_pm_suspend_request(rq) &&
774 pm->pm_step == ide_pm_state_start_suspend)
775 /* Mark drive blocked when starting the suspend sequence. */
776 drive->blocked = 1;
777 else if (blk_pm_resume_request(rq) &&
778 pm->pm_step == ide_pm_state_start_resume) {
779 /*
780 * The first thing we do on wakeup is to wait for BSY bit to
781 * go away (with a looong timeout) as a drive on this hwif may
782 * just be POSTing itself.
783 * We do that before even selecting as the "other" device on
784 * the bus may be broken enough to walk on our toes at this
785 * point.
786 */
787 int rc;
788#ifdef DEBUG_PM
789 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
790#endif
791 rc = ide_wait_not_busy(HWIF(drive), 35000);
792 if (rc)
793 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
794 SELECT_DRIVE(drive);
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +0100795 ide_set_irq(drive, 1);
Al Boldi178184b2006-06-26 00:26:13 -0700796 rc = ide_wait_not_busy(HWIF(drive), 100000);
Jens Axboead3cadd2006-06-13 08:46:57 +0200797 if (rc)
798 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
799 }
800}
801
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802/**
803 * start_request - start of I/O and command issuing for IDE
804 *
805 * start_request() initiates handling of a new I/O request. It
806 * accepts commands and I/O (read/write) requests. It also does
807 * the final remapping for weird stuff like EZDrive. Once
808 * device mapper can work sector level the EZDrive stuff can go away
809 *
810 * FIXME: this function needs a rename
811 */
812
813static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
814{
815 ide_startstop_t startstop;
816 sector_t block;
817
Jens Axboe4aff5e22006-08-10 08:44:47 +0200818 BUG_ON(!blk_rq_started(rq));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819
820#ifdef DEBUG
821 printk("%s: start_request: current=0x%08lx\n",
822 HWIF(drive)->name, (unsigned long) rq);
823#endif
824
825 /* bail early if we've exceeded max_failures */
826 if (drive->max_failures && (drive->failures > drive->max_failures)) {
Aristeu Rozanskib5e1a4e2008-01-25 22:17:04 +0100827 rq->cmd_flags |= REQ_FAILED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828 goto kill_rq;
829 }
830
831 block = rq->sector;
832 if (blk_fs_request(rq) &&
833 (drive->media == ide_disk || drive->media == ide_floppy)) {
834 block += drive->sect0;
835 }
836 /* Yecch - this will shift the entire interval,
837 possibly killing some innocent following sector */
838 if (block == 0 && drive->remap_0_to_1 == 1)
839 block = 1; /* redirect MBR access to EZ-Drive partn table */
840
Jens Axboead3cadd2006-06-13 08:46:57 +0200841 if (blk_pm_request(rq))
842 ide_check_pm_state(drive, rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843
844 SELECT_DRIVE(drive);
845 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
846 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
847 return startstop;
848 }
849 if (!drive->special.all) {
850 ide_driver_t *drv;
851
Suleiman Souhlal513daad2007-03-26 23:03:20 +0200852 /*
853 * We reset the drive so we need to issue a SETFEATURES.
854 * Do it _after_ do_special() restored device parameters.
855 */
856 if (drive->current_speed == 0xff)
857 ide_config_drive_speed(drive, drive->desired_speed);
858
Bartlomiej Zolnierkiewicz7267c332008-01-26 20:13:13 +0100859 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860 return execute_drive_cmd(drive, rq);
861 else if (blk_pm_request(rq)) {
Jens Axboec00895a2006-09-30 20:29:12 +0200862 struct request_pm_state *pm = rq->data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863#ifdef DEBUG_PM
864 printk("%s: start_power_step(step: %d)\n",
865 drive->name, rq->pm->pm_step);
866#endif
867 startstop = ide_start_power_step(drive, rq);
868 if (startstop == ide_stopped &&
Jens Axboead3cadd2006-06-13 08:46:57 +0200869 pm->pm_step == ide_pm_state_completed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 ide_complete_pm_request(drive, rq);
871 return startstop;
872 }
873
874 drv = *(ide_driver_t **)rq->rq_disk->private_data;
875 return drv->do_request(drive, rq, block);
876 }
877 return do_special(drive);
878kill_rq:
879 ide_kill_rq(drive, rq);
880 return ide_stopped;
881}
882
883/**
884 * ide_stall_queue - pause an IDE device
885 * @drive: drive to stall
886 * @timeout: time to stall for (jiffies)
887 *
888 * ide_stall_queue() can be used by a drive to give excess bandwidth back
889 * to the hwgroup by sleeping for timeout jiffies.
890 */
891
892void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
893{
894 if (timeout > WAIT_WORSTCASE)
895 timeout = WAIT_WORSTCASE;
896 drive->sleep = timeout + jiffies;
897 drive->sleeping = 1;
898}
899
900EXPORT_SYMBOL(ide_stall_queue);
901
902#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
903
904/**
905 * choose_drive - select a drive to service
906 * @hwgroup: hardware group to select on
907 *
908 * choose_drive() selects the next drive which will be serviced.
909 * This is necessary because the IDE layer can't issue commands
910 * to both drives on the same cable, unlike SCSI.
911 */
912
913static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
914{
915 ide_drive_t *drive, *best;
916
917repeat:
918 best = NULL;
919 drive = hwgroup->drive;
920
921 /*
922 * drive is doing pre-flush, ordered write, post-flush sequence. even
923 * though that is 3 requests, it must be seen as a single transaction.
924 * we must not preempt this drive until that is complete
925 */
926 if (blk_queue_flushing(drive->queue)) {
927 /*
928 * small race where queue could get replugged during
929 * the 3-request flush cycle, just yank the plug since
930 * we want it to finish asap
931 */
932 blk_remove_plug(drive->queue);
933 return drive;
934 }
935
936 do {
937 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
938 && !elv_queue_empty(drive->queue)) {
939 if (!best
940 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
941 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
942 {
943 if (!blk_queue_plugged(drive->queue))
944 best = drive;
945 }
946 }
947 } while ((drive = drive->next) != hwgroup->drive);
948 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
949 long t = (signed long)(WAKEUP(best) - jiffies);
950 if (t >= WAIT_MIN_SLEEP) {
951 /*
952 * We *may* have some time to spare, but first let's see if
953 * someone can potentially benefit from our nice mood today..
954 */
955 drive = best->next;
956 do {
957 if (!drive->sleeping
958 && time_before(jiffies - best->service_time, WAKEUP(drive))
959 && time_before(WAKEUP(drive), jiffies + t))
960 {
961 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
962 goto repeat;
963 }
964 } while ((drive = drive->next) != best);
965 }
966 }
967 return best;
968}
969
970/*
971 * Issue a new request to a drive from hwgroup
972 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
973 *
974 * A hwgroup is a serialized group of IDE interfaces. Usually there is
975 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
976 * may have both interfaces in a single hwgroup to "serialize" access.
977 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
978 * together into one hwgroup for serialized access.
979 *
980 * Note also that several hwgroups can end up sharing a single IRQ,
981 * possibly along with many other devices. This is especially common in
982 * PCI-based systems with off-board IDE controller cards.
983 *
984 * The IDE driver uses the single global ide_lock spinlock to protect
985 * access to the request queues, and to protect the hwgroup->busy flag.
986 *
987 * The first thread into the driver for a particular hwgroup sets the
988 * hwgroup->busy flag to indicate that this hwgroup is now active,
989 * and then initiates processing of the top request from the request queue.
990 *
991 * Other threads attempting entry notice the busy setting, and will simply
992 * queue their new requests and exit immediately. Note that hwgroup->busy
993 * remains set even when the driver is merely awaiting the next interrupt.
994 * Thus, the meaning is "this hwgroup is busy processing a request".
995 *
996 * When processing of a request completes, the completing thread or IRQ-handler
997 * will start the next request from the queue. If no more work remains,
998 * the driver will clear the hwgroup->busy flag and exit.
999 *
1000 * The ide_lock (spinlock) is used to protect all access to the
1001 * hwgroup->busy flag, but is otherwise not needed for most processing in
1002 * the driver. This makes the driver much more friendlier to shared IRQs
1003 * than previous designs, while remaining 100% (?) SMP safe and capable.
1004 */
1005static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1006{
1007 ide_drive_t *drive;
1008 ide_hwif_t *hwif;
1009 struct request *rq;
1010 ide_startstop_t startstop;
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001011 int loops = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012
1013 /* for atari only: POSSIBLY BROKEN HERE(?) */
1014 ide_get_lock(ide_intr, hwgroup);
1015
1016 /* caller must own ide_lock */
1017 BUG_ON(!irqs_disabled());
1018
1019 while (!hwgroup->busy) {
1020 hwgroup->busy = 1;
1021 drive = choose_drive(hwgroup);
1022 if (drive == NULL) {
1023 int sleeping = 0;
1024 unsigned long sleep = 0; /* shut up, gcc */
1025 hwgroup->rq = NULL;
1026 drive = hwgroup->drive;
1027 do {
1028 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1029 sleeping = 1;
1030 sleep = drive->sleep;
1031 }
1032 } while ((drive = drive->next) != hwgroup->drive);
1033 if (sleeping) {
1034 /*
1035 * Take a short snooze, and then wake up this hwgroup again.
1036 * This gives other hwgroups on the same a chance to
1037 * play fairly with us, just in case there are big differences
1038 * in relative throughputs.. don't want to hog the cpu too much.
1039 */
1040 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1041 sleep = jiffies + WAIT_MIN_SLEEP;
1042#if 1
1043 if (timer_pending(&hwgroup->timer))
1044 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1045#endif
1046 /* so that ide_timer_expiry knows what to do */
1047 hwgroup->sleeping = 1;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001048 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049 mod_timer(&hwgroup->timer, sleep);
1050 /* we purposely leave hwgroup->busy==1
1051 * while sleeping */
1052 } else {
1053 /* Ugly, but how can we sleep for the lock
1054 * otherwise? perhaps from tq_disk?
1055 */
1056
1057 /* for atari only */
1058 ide_release_lock();
1059 hwgroup->busy = 0;
1060 }
1061
1062 /* no more work for this hwgroup (for now) */
1063 return;
1064 }
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001065 again:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 hwif = HWIF(drive);
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +01001067 if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) {
Bartlomiej Zolnierkiewicz7299a392008-01-25 22:17:14 +01001068 /*
1069 * set nIEN for previous hwif, drives in the
1070 * quirk_list may not like intr setups/cleanups
1071 */
1072 if (drive->quirk_list != 1)
Bartlomiej Zolnierkiewicz81ca6912008-01-26 20:13:08 +01001073 ide_set_irq(drive, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001074 }
1075 hwgroup->hwif = hwif;
1076 hwgroup->drive = drive;
1077 drive->sleeping = 0;
1078 drive->service_start = jiffies;
1079
1080 if (blk_queue_plugged(drive->queue)) {
1081 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1082 break;
1083 }
1084
1085 /*
1086 * we know that the queue isn't empty, but this can happen
1087 * if the q->prep_rq_fn() decides to kill a request
1088 */
1089 rq = elv_next_request(drive->queue);
1090 if (!rq) {
1091 hwgroup->busy = 0;
1092 break;
1093 }
1094
1095 /*
1096 * Sanity: don't accept a request that isn't a PM request
1097 * if we are currently power managed. This is very important as
1098 * blk_stop_queue() doesn't prevent the elv_next_request()
1099 * above to return us whatever is in the queue. Since we call
1100 * ide_do_request() ourselves, we end up taking requests while
1101 * the queue is blocked...
1102 *
1103 * We let requests forced at head of queue with ide-preempt
1104 * though. I hope that doesn't happen too much, hopefully not
1105 * unless the subdriver triggers such a thing in its own PM
1106 * state machine.
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001107 *
1108 * We count how many times we loop here to make sure we service
1109 * all drives in the hwgroup without looping for ever
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 */
Jens Axboe4aff5e22006-08-10 08:44:47 +02001111 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) {
Benjamin Herrenschmidt867f8b42005-10-09 10:37:47 +10001112 drive = drive->next ? drive->next : hwgroup->drive;
1113 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1114 goto again;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001115 /* We clear busy, there should be no pending ATA command at this point. */
1116 hwgroup->busy = 0;
1117 break;
1118 }
1119
1120 hwgroup->rq = rq;
1121
1122 /*
1123 * Some systems have trouble with IDE IRQs arriving while
1124 * the driver is still setting things up. So, here we disable
1125 * the IRQ used by this interface while the request is being started.
1126 * This may look bad at first, but pretty much the same thing
1127 * happens anyway when any interrupt comes in, IDE or otherwise
1128 * -- the kernel masks the IRQ while it is being handled.
1129 */
1130 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1131 disable_irq_nosync(hwif->irq);
1132 spin_unlock(&ide_lock);
Ingo Molnar366c7f52006-07-03 00:25:25 -07001133 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134 /* allow other IRQs while we start this request */
1135 startstop = start_request(drive, rq);
1136 spin_lock_irq(&ide_lock);
1137 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1138 enable_irq(hwif->irq);
1139 if (startstop == ide_stopped)
1140 hwgroup->busy = 0;
1141 }
1142}
1143
1144/*
1145 * Passes the stuff to ide_do_request
1146 */
Jens Axboe165125e2007-07-24 09:28:11 +02001147void do_ide_request(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148{
1149 ide_drive_t *drive = q->queuedata;
1150
1151 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1152}
1153
1154/*
1155 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1156 * retry the current request in pio mode instead of risking tossing it
1157 * all away
1158 */
1159static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1160{
1161 ide_hwif_t *hwif = HWIF(drive);
1162 struct request *rq;
1163 ide_startstop_t ret = ide_stopped;
1164
1165 /*
1166 * end current dma transaction
1167 */
1168
1169 if (error < 0) {
1170 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
Bartlomiej Zolnierkiewicz5e37bdc2008-04-26 22:25:24 +02001171 (void)hwif->dma_ops->dma_end(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001172 ret = ide_error(drive, "dma timeout error",
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +01001173 ide_read_status(drive));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174 } else {
1175 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
Bartlomiej Zolnierkiewicz5e37bdc2008-04-26 22:25:24 +02001176 hwif->dma_ops->dma_timeout(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001177 }
1178
1179 /*
1180 * disable dma for now, but remember that we did so because of
1181 * a timeout -- we'll reenable after we finish this next request
1182 * (or rather the first chunk of it) in pio.
1183 */
1184 drive->retry_pio++;
1185 drive->state = DMA_PIO_RETRY;
Bartlomiej Zolnierkiewicz4a546e02008-01-26 20:13:01 +01001186 ide_dma_off_quietly(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187
1188 /*
1189 * un-busy drive etc (hwgroup->busy is cleared on return) and
1190 * make sure request is sane
1191 */
1192 rq = HWGROUP(drive)->rq;
Hua Zhongce42f192006-10-03 01:14:15 -07001193
1194 if (!rq)
1195 goto out;
1196
Linus Torvalds1da177e2005-04-16 15:20:36 -07001197 HWGROUP(drive)->rq = NULL;
1198
1199 rq->errors = 0;
1200
1201 if (!rq->bio)
1202 goto out;
1203
1204 rq->sector = rq->bio->bi_sector;
1205 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1206 rq->hard_cur_sectors = rq->current_nr_sectors;
1207 rq->buffer = bio_data(rq->bio);
1208out:
1209 return ret;
1210}
1211
1212/**
1213 * ide_timer_expiry - handle lack of an IDE interrupt
1214 * @data: timer callback magic (hwgroup)
1215 *
1216 * An IDE command has timed out before the expected drive return
1217 * occurred. At this point we attempt to clean up the current
1218 * mess. If the current handler includes an expiry handler then
1219 * we invoke the expiry handler, and providing it is happy the
1220 * work is done. If that fails we apply generic recovery rules
1221 * invoking the handler and checking the drive DMA status. We
1222 * have an excessively incestuous relationship with the DMA
1223 * logic that wants cleaning up.
1224 */
1225
1226void ide_timer_expiry (unsigned long data)
1227{
1228 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1229 ide_handler_t *handler;
1230 ide_expiry_t *expiry;
1231 unsigned long flags;
1232 unsigned long wait = -1;
1233
1234 spin_lock_irqsave(&ide_lock, flags);
1235
Suleiman Souhlal23450312007-04-10 22:38:37 +02001236 if (((handler = hwgroup->handler) == NULL) ||
1237 (hwgroup->req_gen != hwgroup->req_gen_timer)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001238 /*
1239 * Either a marginal timeout occurred
1240 * (got the interrupt just as timer expired),
1241 * or we were "sleeping" to give other devices a chance.
1242 * Either way, we don't really want to complain about anything.
1243 */
1244 if (hwgroup->sleeping) {
1245 hwgroup->sleeping = 0;
1246 hwgroup->busy = 0;
1247 }
1248 } else {
1249 ide_drive_t *drive = hwgroup->drive;
1250 if (!drive) {
1251 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1252 hwgroup->handler = NULL;
1253 } else {
1254 ide_hwif_t *hwif;
1255 ide_startstop_t startstop = ide_stopped;
1256 if (!hwgroup->busy) {
1257 hwgroup->busy = 1; /* paranoia */
1258 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1259 }
1260 if ((expiry = hwgroup->expiry) != NULL) {
1261 /* continue */
1262 if ((wait = expiry(drive)) > 0) {
1263 /* reset timer */
1264 hwgroup->timer.expires = jiffies + wait;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001265 hwgroup->req_gen_timer = hwgroup->req_gen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001266 add_timer(&hwgroup->timer);
1267 spin_unlock_irqrestore(&ide_lock, flags);
1268 return;
1269 }
1270 }
1271 hwgroup->handler = NULL;
1272 /*
1273 * We need to simulate a real interrupt when invoking
1274 * the handler() function, which means we need to
1275 * globally mask the specific IRQ:
1276 */
1277 spin_unlock(&ide_lock);
1278 hwif = HWIF(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279 /* disable_irq_nosync ?? */
1280 disable_irq(hwif->irq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281 /* local CPU only,
1282 * as if we were handling an interrupt */
1283 local_irq_disable();
1284 if (hwgroup->polling) {
1285 startstop = handler(drive);
1286 } else if (drive_is_ready(drive)) {
1287 if (drive->waiting_for_dma)
Bartlomiej Zolnierkiewicz5e37bdc2008-04-26 22:25:24 +02001288 hwif->dma_ops->dma_lost_irq(drive);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289 (void)ide_ack_intr(hwif);
1290 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1291 startstop = handler(drive);
1292 } else {
1293 if (drive->waiting_for_dma) {
1294 startstop = ide_dma_timeout_retry(drive, wait);
1295 } else
1296 startstop =
Bartlomiej Zolnierkiewiczc47137a2008-02-06 02:57:51 +01001297 ide_error(drive, "irq timeout",
1298 ide_read_status(drive));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 }
1300 drive->service_time = jiffies - drive->service_start;
1301 spin_lock_irq(&ide_lock);
1302 enable_irq(hwif->irq);
1303 if (startstop == ide_stopped)
1304 hwgroup->busy = 0;
1305 }
1306 }
1307 ide_do_request(hwgroup, IDE_NO_IRQ);
1308 spin_unlock_irqrestore(&ide_lock, flags);
1309}
1310
1311/**
1312 * unexpected_intr - handle an unexpected IDE interrupt
1313 * @irq: interrupt line
1314 * @hwgroup: hwgroup being processed
1315 *
1316 * There's nothing really useful we can do with an unexpected interrupt,
1317 * other than reading the status register (to clear it), and logging it.
1318 * There should be no way that an irq can happen before we're ready for it,
1319 * so we needn't worry much about losing an "important" interrupt here.
1320 *
1321 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1322 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1323 * looks "good", we just ignore the interrupt completely.
1324 *
1325 * This routine assumes __cli() is in effect when called.
1326 *
1327 * If an unexpected interrupt happens on irq15 while we are handling irq14
1328 * and if the two interfaces are "serialized" (CMD640), then it looks like
1329 * we could screw up by interfering with a new request being set up for
1330 * irq15.
1331 *
1332 * In reality, this is a non-issue. The new command is not sent unless
1333 * the drive is ready to accept one, in which case we know the drive is
1334 * not trying to interrupt us. And ide_set_handler() is always invoked
1335 * before completing the issuance of any new drive command, so we will not
1336 * be accidentally invoked as a result of any valid command completion
1337 * interrupt.
1338 *
1339 * Note that we must walk the entire hwgroup here. We know which hwif
1340 * is doing the current command, but we don't know which hwif burped
1341 * mysteriously.
1342 */
1343
1344static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1345{
1346 u8 stat;
1347 ide_hwif_t *hwif = hwgroup->hwif;
1348
1349 /*
1350 * handle the unexpected interrupt
1351 */
1352 do {
1353 if (hwif->irq == irq) {
Bartlomiej Zolnierkiewicz4c3032d2008-04-27 15:38:32 +02001354 stat = hwif->INB(hwif->io_ports.status_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1356 /* Try to not flood the console with msgs */
1357 static unsigned long last_msgtime, count;
1358 ++count;
1359 if (time_after(jiffies, last_msgtime + HZ)) {
1360 last_msgtime = jiffies;
1361 printk(KERN_ERR "%s%s: unexpected interrupt, "
1362 "status=0x%02x, count=%ld\n",
1363 hwif->name,
1364 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1365 }
1366 }
1367 }
1368 } while ((hwif = hwif->next) != hwgroup->hwif);
1369}
1370
1371/**
1372 * ide_intr - default IDE interrupt handler
1373 * @irq: interrupt number
1374 * @dev_id: hwif group
1375 * @regs: unused weirdness from the kernel irq layer
1376 *
1377 * This is the default IRQ handler for the IDE layer. You should
1378 * not need to override it. If you do be aware it is subtle in
1379 * places
1380 *
1381 * hwgroup->hwif is the interface in the group currently performing
1382 * a command. hwgroup->drive is the drive and hwgroup->handler is
1383 * the IRQ handler to call. As we issue a command the handlers
1384 * step through multiple states, reassigning the handler to the
1385 * next step in the process. Unlike a smart SCSI controller IDE
1386 * expects the main processor to sequence the various transfer
1387 * stages. We also manage a poll timer to catch up with most
1388 * timeout situations. There are still a few where the handlers
1389 * don't ever decide to give up.
1390 *
1391 * The handler eventually returns ide_stopped to indicate the
1392 * request completed. At this point we issue the next request
1393 * on the hwgroup and the process begins again.
1394 */
1395
David Howells7d12e782006-10-05 14:55:46 +01001396irqreturn_t ide_intr (int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001397{
1398 unsigned long flags;
1399 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1400 ide_hwif_t *hwif;
1401 ide_drive_t *drive;
1402 ide_handler_t *handler;
1403 ide_startstop_t startstop;
1404
1405 spin_lock_irqsave(&ide_lock, flags);
1406 hwif = hwgroup->hwif;
1407
1408 if (!ide_ack_intr(hwif)) {
1409 spin_unlock_irqrestore(&ide_lock, flags);
1410 return IRQ_NONE;
1411 }
1412
1413 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1414 /*
1415 * Not expecting an interrupt from this drive.
1416 * That means this could be:
1417 * (1) an interrupt from another PCI device
1418 * sharing the same PCI INT# as us.
1419 * or (2) a drive just entered sleep or standby mode,
1420 * and is interrupting to let us know.
1421 * or (3) a spurious interrupt of unknown origin.
1422 *
1423 * For PCI, we cannot tell the difference,
1424 * so in that case we just ignore it and hope it goes away.
1425 *
1426 * FIXME: unexpected_intr should be hwif-> then we can
1427 * remove all the ifdef PCI crap
1428 */
1429#ifdef CONFIG_BLK_DEV_IDEPCI
Bartlomiej Zolnierkiewicz425afb62008-02-01 23:09:31 +01001430 if (hwif->chipset != ide_pci)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001431#endif /* CONFIG_BLK_DEV_IDEPCI */
1432 {
1433 /*
1434 * Probably not a shared PCI interrupt,
1435 * so we can safely try to do something about it:
1436 */
1437 unexpected_intr(irq, hwgroup);
1438#ifdef CONFIG_BLK_DEV_IDEPCI
1439 } else {
1440 /*
1441 * Whack the status register, just in case
1442 * we have a leftover pending IRQ.
1443 */
Bartlomiej Zolnierkiewicz4c3032d2008-04-27 15:38:32 +02001444 (void) hwif->INB(hwif->io_ports.status_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001445#endif /* CONFIG_BLK_DEV_IDEPCI */
1446 }
1447 spin_unlock_irqrestore(&ide_lock, flags);
1448 return IRQ_NONE;
1449 }
1450 drive = hwgroup->drive;
1451 if (!drive) {
1452 /*
1453 * This should NEVER happen, and there isn't much
1454 * we could do about it here.
1455 *
1456 * [Note - this can occur if the drive is hot unplugged]
1457 */
1458 spin_unlock_irqrestore(&ide_lock, flags);
1459 return IRQ_HANDLED;
1460 }
1461 if (!drive_is_ready(drive)) {
1462 /*
1463 * This happens regularly when we share a PCI IRQ with
1464 * another device. Unfortunately, it can also happen
1465 * with some buggy drives that trigger the IRQ before
1466 * their status register is up to date. Hopefully we have
1467 * enough advance overhead that the latter isn't a problem.
1468 */
1469 spin_unlock_irqrestore(&ide_lock, flags);
1470 return IRQ_NONE;
1471 }
1472 if (!hwgroup->busy) {
1473 hwgroup->busy = 1; /* paranoia */
1474 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1475 }
1476 hwgroup->handler = NULL;
Suleiman Souhlal23450312007-04-10 22:38:37 +02001477 hwgroup->req_gen++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001478 del_timer(&hwgroup->timer);
1479 spin_unlock(&ide_lock);
1480
Albert Leef0dd8712007-02-17 02:40:21 +01001481 /* Some controllers might set DMA INTR no matter DMA or PIO;
1482 * bmdma status might need to be cleared even for
1483 * PIO interrupts to prevent spurious/lost irq.
1484 */
1485 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma))
1486 /* ide_dma_end() needs bmdma status for error checking.
1487 * So, skip clearing bmdma status here and leave it
1488 * to ide_dma_end() if this is dma interrupt.
1489 */
1490 hwif->ide_dma_clear_irq(drive);
1491
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492 if (drive->unmask)
Ingo Molnar366c7f52006-07-03 00:25:25 -07001493 local_irq_enable_in_hardirq();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001494 /* service this interrupt, may set handler for next interrupt */
1495 startstop = handler(drive);
1496 spin_lock_irq(&ide_lock);
1497
1498 /*
1499 * Note that handler() may have set things up for another
1500 * interrupt to occur soon, but it cannot happen until
1501 * we exit from this routine, because it will be the
1502 * same irq as is currently being serviced here, and Linux
1503 * won't allow another of the same (on any CPU) until we return.
1504 */
1505 drive->service_time = jiffies - drive->service_start;
1506 if (startstop == ide_stopped) {
1507 if (hwgroup->handler == NULL) { /* paranoia */
1508 hwgroup->busy = 0;
1509 ide_do_request(hwgroup, hwif->irq);
1510 } else {
1511 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1512 "on exit\n", drive->name);
1513 }
1514 }
1515 spin_unlock_irqrestore(&ide_lock, flags);
1516 return IRQ_HANDLED;
1517}
1518
1519/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520 * ide_do_drive_cmd - issue IDE special command
1521 * @drive: device to issue command
1522 * @rq: request to issue
1523 * @action: action for processing
1524 *
1525 * This function issues a special IDE device request
1526 * onto the request queue.
1527 *
1528 * If action is ide_wait, then the rq is queued at the end of the
1529 * request queue, and the function sleeps until it has been processed.
1530 * This is for use when invoked from an ioctl handler.
1531 *
1532 * If action is ide_preempt, then the rq is queued at the head of
1533 * the request queue, displacing the currently-being-processed
1534 * request and this function returns immediately without waiting
1535 * for the new rq to be completed. This is VERY DANGEROUS, and is
1536 * intended for careful use by the ATAPI tape/cdrom driver code.
1537 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001538 * If action is ide_end, then the rq is queued at the end of the
1539 * request queue, and the function returns immediately without waiting
1540 * for the new rq to be completed. This is again intended for careful
1541 * use by the ATAPI tape/cdrom driver code.
1542 */
1543
1544int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1545{
1546 unsigned long flags;
1547 ide_hwgroup_t *hwgroup = HWGROUP(drive);
FUJITA Tomonori5f2e1ce2008-07-15 21:21:44 +02001548 int where = ELEVATOR_INSERT_BACK;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001549
1550 rq->errors = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551
FUJITA Tomonori5f2e1ce2008-07-15 21:21:44 +02001552 if (action == ide_preempt)
Bartlomiej Zolnierkiewicze8a96aa2008-07-15 21:21:41 +02001553 where = ELEVATOR_INSERT_FRONT;
1554
Linus Torvalds1da177e2005-04-16 15:20:36 -07001555 spin_lock_irqsave(&ide_lock, flags);
1556 if (action == ide_preempt)
1557 hwgroup->rq = NULL;
Bartlomiej Zolnierkiewiczc6866a62008-07-15 21:21:42 +02001558 __elv_add_request(drive->queue, rq, where, 1);
1559 __generic_unplug_device(drive->queue);
1560 /* the queue is stopped so it won't be plugged+unplugged */
1561 if (blk_pm_resume_request(rq))
1562 do_ide_request(drive->queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001563 spin_unlock_irqrestore(&ide_lock, flags);
1564
FUJITA Tomonori5f2e1ce2008-07-15 21:21:44 +02001565 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001566}
1567
1568EXPORT_SYMBOL(ide_do_drive_cmd);
Bartlomiej Zolnierkiewicz2fc57382008-01-25 22:17:13 +01001569
1570void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma)
1571{
1572 ide_task_t task;
1573
1574 memset(&task, 0, sizeof(task));
1575 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
1576 IDE_TFLAG_OUT_FEATURE | tf_flags;
1577 task.tf.feature = dma; /* Use PIO/DMA */
1578 task.tf.lbam = bcount & 0xff;
1579 task.tf.lbah = (bcount >> 8) & 0xff;
1580
Bartlomiej Zolnierkiewicz089c5c72008-04-28 23:44:39 +02001581 ide_tf_dump(drive->name, &task.tf);
Bartlomiej Zolnierkiewicz94cd5b62008-04-28 23:44:40 +02001582 drive->hwif->tf_load(drive, &task);
Bartlomiej Zolnierkiewicz2fc57382008-01-25 22:17:13 +01001583}
1584
1585EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load);
Bartlomiej Zolnierkiewicz9f87abe2008-04-28 23:44:41 +02001586
1587void ide_pad_transfer(ide_drive_t *drive, int write, int len)
1588{
1589 ide_hwif_t *hwif = drive->hwif;
1590 u8 buf[4] = { 0 };
1591
1592 while (len > 0) {
1593 if (write)
1594 hwif->output_data(drive, NULL, buf, min(4, len));
1595 else
1596 hwif->input_data(drive, NULL, buf, min(4, len));
1597 len -= 4;
1598 }
1599}
1600EXPORT_SYMBOL_GPL(ide_pad_transfer);