4 * Basic PIO and command management functionality.
6 * This code was split off from ide.c. See ide.c for history and original
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
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.
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.
27 #include <linux/module.h>
28 #include <linux/types.h>
29 #include <linux/string.h>
30 #include <linux/kernel.h>
31 #include <linux/timer.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/hdreg.h>
44 #include <linux/completion.h>
45 #include <linux/reboot.h>
46 #include <linux/cdrom.h>
47 #include <linux/seq_file.h>
48 #include <linux/device.h>
49 #include <linux/kmod.h>
50 #include <linux/scatterlist.h>
51 #include <linux/bitops.h>
53 #include <asm/byteorder.h>
55 #include <asm/uaccess.h>
58 static int __ide_end_request(ide_drive_t
*drive
, struct request
*rq
,
59 int uptodate
, unsigned int nr_bytes
, int dequeue
)
65 error
= uptodate
? uptodate
: -EIO
;
68 * if failfast is set on a request, override number of sectors and
69 * complete the whole request right now
71 if (blk_noretry_request(rq
) && error
)
72 nr_bytes
= rq
->hard_nr_sectors
<< 9;
74 if (!blk_fs_request(rq
) && error
&& !rq
->errors
)
78 * decide whether to reenable DMA -- 3 is a random magic for now,
79 * if we DMA timeout more than 3 times, just stay in PIO
81 if ((drive
->dev_flags
& IDE_DFLAG_DMA_PIO_RETRY
) &&
82 drive
->retry_pio
<= 3) {
83 drive
->dev_flags
&= ~IDE_DFLAG_DMA_PIO_RETRY
;
87 if (!__blk_end_request(rq
, error
, nr_bytes
)) {
89 HWGROUP(drive
)->rq
= NULL
;
97 * ide_end_request - complete an IDE I/O
98 * @drive: IDE device for the I/O
100 * @nr_sectors: number of sectors completed
102 * This is our end_request wrapper function. We complete the I/O
103 * update random number input and dequeue the request, which if
104 * it was tagged may be out of order.
107 int ide_end_request (ide_drive_t
*drive
, int uptodate
, int nr_sectors
)
109 unsigned int nr_bytes
= nr_sectors
<< 9;
115 * room for locking improvements here, the calls below don't
116 * need the queue lock held at all
118 spin_lock_irqsave(&ide_lock
, flags
);
119 rq
= HWGROUP(drive
)->rq
;
122 if (blk_pc_request(rq
))
123 nr_bytes
= rq
->data_len
;
125 nr_bytes
= rq
->hard_cur_sectors
<< 9;
128 ret
= __ide_end_request(drive
, rq
, uptodate
, nr_bytes
, 1);
130 spin_unlock_irqrestore(&ide_lock
, flags
);
133 EXPORT_SYMBOL(ide_end_request
);
136 * Power Management state machine. This one is rather trivial for now,
137 * we should probably add more, like switching back to PIO on suspend
138 * to help some BIOSes, re-do the door locking on resume, etc...
142 ide_pm_flush_cache
= ide_pm_state_start_suspend
,
145 idedisk_pm_restore_pio
= ide_pm_state_start_resume
,
150 static void ide_complete_power_step(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 error
)
152 struct request_pm_state
*pm
= rq
->data
;
154 if (drive
->media
!= ide_disk
)
157 switch (pm
->pm_step
) {
158 case ide_pm_flush_cache
: /* Suspend step 1 (flush cache) complete */
159 if (pm
->pm_state
== PM_EVENT_FREEZE
)
160 pm
->pm_step
= ide_pm_state_completed
;
162 pm
->pm_step
= idedisk_pm_standby
;
164 case idedisk_pm_standby
: /* Suspend step 2 (standby) complete */
165 pm
->pm_step
= ide_pm_state_completed
;
167 case idedisk_pm_restore_pio
: /* Resume step 1 complete */
168 pm
->pm_step
= idedisk_pm_idle
;
170 case idedisk_pm_idle
: /* Resume step 2 (idle) complete */
171 pm
->pm_step
= ide_pm_restore_dma
;
176 static ide_startstop_t
ide_start_power_step(ide_drive_t
*drive
, struct request
*rq
)
178 struct request_pm_state
*pm
= rq
->data
;
179 ide_task_t
*args
= rq
->special
;
181 memset(args
, 0, sizeof(*args
));
183 switch (pm
->pm_step
) {
184 case ide_pm_flush_cache
: /* Suspend step 1 (flush cache) */
185 if (drive
->media
!= ide_disk
)
187 /* Not supported? Switch to next step now. */
188 if (ata_id_flush_enabled(drive
->id
) == 0 ||
189 (drive
->dev_flags
& IDE_DFLAG_WCACHE
) == 0) {
190 ide_complete_power_step(drive
, rq
, 0, 0);
193 if (ata_id_flush_ext_enabled(drive
->id
))
194 args
->tf
.command
= ATA_CMD_FLUSH_EXT
;
196 args
->tf
.command
= ATA_CMD_FLUSH
;
199 case idedisk_pm_standby
: /* Suspend step 2 (standby) */
200 args
->tf
.command
= ATA_CMD_STANDBYNOW1
;
203 case idedisk_pm_restore_pio
: /* Resume step 1 (restore PIO) */
204 ide_set_max_pio(drive
);
206 * skip idedisk_pm_idle for ATAPI devices
208 if (drive
->media
!= ide_disk
)
209 pm
->pm_step
= ide_pm_restore_dma
;
211 ide_complete_power_step(drive
, rq
, 0, 0);
214 case idedisk_pm_idle
: /* Resume step 2 (idle) */
215 args
->tf
.command
= ATA_CMD_IDLEIMMEDIATE
;
218 case ide_pm_restore_dma
: /* Resume step 3 (restore DMA) */
220 * Right now, all we do is call ide_set_dma(drive),
221 * we could be smarter and check for current xfer_speed
222 * in struct drive etc...
224 if (drive
->hwif
->dma_ops
== NULL
)
227 * TODO: respect IDE_DFLAG_USING_DMA
232 pm
->pm_step
= ide_pm_state_completed
;
236 args
->tf_flags
= IDE_TFLAG_TF
| IDE_TFLAG_DEVICE
;
237 args
->data_phase
= TASKFILE_NO_DATA
;
238 return do_rw_taskfile(drive
, args
);
242 * ide_end_dequeued_request - complete an IDE I/O
243 * @drive: IDE device for the I/O
245 * @nr_sectors: number of sectors completed
247 * Complete an I/O that is no longer on the request queue. This
248 * typically occurs when we pull the request and issue a REQUEST_SENSE.
249 * We must still finish the old request but we must not tamper with the
250 * queue in the meantime.
252 * NOTE: This path does not handle barrier, but barrier is not supported
256 int ide_end_dequeued_request(ide_drive_t
*drive
, struct request
*rq
,
257 int uptodate
, int nr_sectors
)
262 spin_lock_irqsave(&ide_lock
, flags
);
263 BUG_ON(!blk_rq_started(rq
));
264 ret
= __ide_end_request(drive
, rq
, uptodate
, nr_sectors
<< 9, 0);
265 spin_unlock_irqrestore(&ide_lock
, flags
);
269 EXPORT_SYMBOL_GPL(ide_end_dequeued_request
);
273 * ide_complete_pm_request - end the current Power Management request
274 * @drive: target drive
277 * This function cleans up the current PM request and stops the queue
280 static void ide_complete_pm_request (ide_drive_t
*drive
, struct request
*rq
)
285 printk("%s: completing PM request, %s\n", drive
->name
,
286 blk_pm_suspend_request(rq
) ? "suspend" : "resume");
288 spin_lock_irqsave(&ide_lock
, flags
);
289 if (blk_pm_suspend_request(rq
)) {
290 blk_stop_queue(drive
->queue
);
292 drive
->dev_flags
&= ~IDE_DFLAG_BLOCKED
;
293 blk_start_queue(drive
->queue
);
295 HWGROUP(drive
)->rq
= NULL
;
296 if (__blk_end_request(rq
, 0, 0))
298 spin_unlock_irqrestore(&ide_lock
, flags
);
302 * ide_end_drive_cmd - end an explicit drive command
307 * Clean up after success/failure of an explicit drive command.
308 * These get thrown onto the queue so they are synchronized with
309 * real I/O operations on the drive.
311 * In LBA48 mode we have to read the register set twice to get
312 * all the extra information out.
315 void ide_end_drive_cmd (ide_drive_t
*drive
, u8 stat
, u8 err
)
320 spin_lock_irqsave(&ide_lock
, flags
);
321 rq
= HWGROUP(drive
)->rq
;
322 spin_unlock_irqrestore(&ide_lock
, flags
);
324 if (rq
->cmd_type
== REQ_TYPE_ATA_TASKFILE
) {
325 ide_task_t
*task
= (ide_task_t
*)rq
->special
;
328 rq
->errors
= !OK_STAT(stat
, ATA_DRDY
, BAD_STAT
);
331 struct ide_taskfile
*tf
= &task
->tf
;
336 drive
->hwif
->tp_ops
->tf_read(drive
, task
);
338 if (task
->tf_flags
& IDE_TFLAG_DYN
)
341 } else if (blk_pm_request(rq
)) {
342 struct request_pm_state
*pm
= rq
->data
;
344 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
345 drive
->name
, rq
->pm
->pm_step
, stat
, err
);
347 ide_complete_power_step(drive
, rq
, stat
, err
);
348 if (pm
->pm_step
== ide_pm_state_completed
)
349 ide_complete_pm_request(drive
, rq
);
353 spin_lock_irqsave(&ide_lock
, flags
);
354 HWGROUP(drive
)->rq
= NULL
;
356 if (unlikely(__blk_end_request(rq
, (rq
->errors
? -EIO
: 0),
359 spin_unlock_irqrestore(&ide_lock
, flags
);
362 EXPORT_SYMBOL(ide_end_drive_cmd
);
364 static void ide_kill_rq(ide_drive_t
*drive
, struct request
*rq
)
369 drv
= *(ide_driver_t
**)rq
->rq_disk
->private_data
;
370 drv
->end_request(drive
, 0, 0);
372 ide_end_request(drive
, 0, 0);
375 static ide_startstop_t
ide_ata_error(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 err
)
377 ide_hwif_t
*hwif
= drive
->hwif
;
379 if ((stat
& ATA_BUSY
) ||
380 ((stat
& ATA_DF
) && (drive
->dev_flags
& IDE_DFLAG_NOWERR
) == 0)) {
381 /* other bits are useless when BUSY */
382 rq
->errors
|= ERROR_RESET
;
383 } else if (stat
& ATA_ERR
) {
384 /* err has different meaning on cdrom and tape */
385 if (err
== ATA_ABORTED
) {
386 if (drive
->select
.b
.lba
&&
387 /* some newer drives don't support ATA_CMD_INIT_DEV_PARAMS */
388 hwif
->tp_ops
->read_status(hwif
) == ATA_CMD_INIT_DEV_PARAMS
)
390 } else if ((err
& BAD_CRC
) == BAD_CRC
) {
391 /* UDMA crc error, just retry the operation */
393 } else if (err
& (ATA_BBK
| ATA_UNC
)) {
394 /* retries won't help these */
395 rq
->errors
= ERROR_MAX
;
396 } else if (err
& ATA_TRK0NF
) {
397 /* help it find track zero */
398 rq
->errors
|= ERROR_RECAL
;
402 if ((stat
& ATA_DRQ
) && rq_data_dir(rq
) == READ
&&
403 (hwif
->host_flags
& IDE_HFLAG_ERROR_STOPS_FIFO
) == 0) {
404 int nsect
= drive
->mult_count
? drive
->mult_count
: 1;
406 ide_pad_transfer(drive
, READ
, nsect
* SECTOR_SIZE
);
409 if (rq
->errors
>= ERROR_MAX
|| blk_noretry_request(rq
)) {
410 ide_kill_rq(drive
, rq
);
414 if (hwif
->tp_ops
->read_status(hwif
) & (ATA_BUSY
| ATA_DRQ
))
415 rq
->errors
|= ERROR_RESET
;
417 if ((rq
->errors
& ERROR_RESET
) == ERROR_RESET
) {
419 return ide_do_reset(drive
);
422 if ((rq
->errors
& ERROR_RECAL
) == ERROR_RECAL
)
423 drive
->special
.b
.recalibrate
= 1;
430 static ide_startstop_t
ide_atapi_error(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 err
)
432 ide_hwif_t
*hwif
= drive
->hwif
;
434 if ((stat
& ATA_BUSY
) ||
435 ((stat
& ATA_DF
) && (drive
->dev_flags
& IDE_DFLAG_NOWERR
) == 0)) {
436 /* other bits are useless when BUSY */
437 rq
->errors
|= ERROR_RESET
;
439 /* add decoding error stuff */
442 if (hwif
->tp_ops
->read_status(hwif
) & (ATA_BUSY
| ATA_DRQ
))
444 hwif
->tp_ops
->exec_command(hwif
, ATA_CMD_IDLEIMMEDIATE
);
446 if (rq
->errors
>= ERROR_MAX
) {
447 ide_kill_rq(drive
, rq
);
449 if ((rq
->errors
& ERROR_RESET
) == ERROR_RESET
) {
451 return ide_do_reset(drive
);
460 __ide_error(ide_drive_t
*drive
, struct request
*rq
, u8 stat
, u8 err
)
462 if (drive
->media
== ide_disk
)
463 return ide_ata_error(drive
, rq
, stat
, err
);
464 return ide_atapi_error(drive
, rq
, stat
, err
);
467 EXPORT_SYMBOL_GPL(__ide_error
);
470 * ide_error - handle an error on the IDE
471 * @drive: drive the error occurred on
472 * @msg: message to report
475 * ide_error() takes action based on the error returned by the drive.
476 * For normal I/O that may well include retries. We deal with
477 * both new-style (taskfile) and old style command handling here.
478 * In the case of taskfile command handling there is work left to
482 ide_startstop_t
ide_error (ide_drive_t
*drive
, const char *msg
, u8 stat
)
487 err
= ide_dump_status(drive
, msg
, stat
);
489 if ((rq
= HWGROUP(drive
)->rq
) == NULL
)
492 /* retry only "normal" I/O: */
493 if (!blk_fs_request(rq
)) {
495 ide_end_drive_cmd(drive
, stat
, err
);
502 drv
= *(ide_driver_t
**)rq
->rq_disk
->private_data
;
503 return drv
->error(drive
, rq
, stat
, err
);
505 return __ide_error(drive
, rq
, stat
, err
);
508 EXPORT_SYMBOL_GPL(ide_error
);
510 static void ide_tf_set_specify_cmd(ide_drive_t
*drive
, struct ide_taskfile
*tf
)
512 tf
->nsect
= drive
->sect
;
513 tf
->lbal
= drive
->sect
;
514 tf
->lbam
= drive
->cyl
;
515 tf
->lbah
= drive
->cyl
>> 8;
516 tf
->device
= ((drive
->head
- 1) | drive
->select
.all
) & ~ATA_LBA
;
517 tf
->command
= ATA_CMD_INIT_DEV_PARAMS
;
520 static void ide_tf_set_restore_cmd(ide_drive_t
*drive
, struct ide_taskfile
*tf
)
522 tf
->nsect
= drive
->sect
;
523 tf
->command
= ATA_CMD_RESTORE
;
526 static void ide_tf_set_setmult_cmd(ide_drive_t
*drive
, struct ide_taskfile
*tf
)
528 tf
->nsect
= drive
->mult_req
;
529 tf
->command
= ATA_CMD_SET_MULTI
;
532 static ide_startstop_t
ide_disk_special(ide_drive_t
*drive
)
534 special_t
*s
= &drive
->special
;
537 memset(&args
, 0, sizeof(ide_task_t
));
538 args
.data_phase
= TASKFILE_NO_DATA
;
540 if (s
->b
.set_geometry
) {
541 s
->b
.set_geometry
= 0;
542 ide_tf_set_specify_cmd(drive
, &args
.tf
);
543 } else if (s
->b
.recalibrate
) {
544 s
->b
.recalibrate
= 0;
545 ide_tf_set_restore_cmd(drive
, &args
.tf
);
546 } else if (s
->b
.set_multmode
) {
547 s
->b
.set_multmode
= 0;
548 ide_tf_set_setmult_cmd(drive
, &args
.tf
);
550 int special
= s
->all
;
552 printk(KERN_ERR
"%s: bad special flag: 0x%02x\n", drive
->name
, special
);
556 args
.tf_flags
= IDE_TFLAG_TF
| IDE_TFLAG_DEVICE
|
557 IDE_TFLAG_CUSTOM_HANDLER
;
559 do_rw_taskfile(drive
, &args
);
565 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
567 static int set_pio_mode_abuse(ide_hwif_t
*hwif
, u8 req_pio
)
576 return (hwif
->host_flags
& IDE_HFLAG_ABUSE_DMA_MODES
) ? 1 : 0;
579 return (hwif
->host_flags
& IDE_HFLAG_ABUSE_PREFETCH
) ? 1 : 0;
582 return (hwif
->host_flags
& IDE_HFLAG_ABUSE_FAST_DEVSEL
) ? 1 : 0;
589 * do_special - issue some special commands
590 * @drive: drive the command is for
592 * do_special() is used to issue ATA_CMD_INIT_DEV_PARAMS,
593 * ATA_CMD_RESTORE and ATA_CMD_SET_MULTI commands to a drive.
595 * It used to do much more, but has been scaled back.
598 static ide_startstop_t
do_special (ide_drive_t
*drive
)
600 special_t
*s
= &drive
->special
;
603 printk("%s: do_special: 0x%02x\n", drive
->name
, s
->all
);
606 ide_hwif_t
*hwif
= drive
->hwif
;
607 const struct ide_port_ops
*port_ops
= hwif
->port_ops
;
608 u8 req_pio
= drive
->tune_req
;
612 if (set_pio_mode_abuse(drive
->hwif
, req_pio
)) {
614 * take ide_lock for IDE_DFLAG_[NO_]UNMASK/[NO_]IO_32BIT
616 if (req_pio
== 8 || req_pio
== 9) {
619 spin_lock_irqsave(&ide_lock
, flags
);
620 port_ops
->set_pio_mode(drive
, req_pio
);
621 spin_unlock_irqrestore(&ide_lock
, flags
);
623 port_ops
->set_pio_mode(drive
, req_pio
);
626 !!(drive
->dev_flags
& IDE_DFLAG_USING_DMA
);
628 ide_set_pio(drive
, req_pio
);
630 if (hwif
->host_flags
& IDE_HFLAG_SET_PIO_MODE_KEEP_DMA
) {
638 if (drive
->media
== ide_disk
)
639 return ide_disk_special(drive
);
647 void ide_map_sg(ide_drive_t
*drive
, struct request
*rq
)
649 ide_hwif_t
*hwif
= drive
->hwif
;
650 struct scatterlist
*sg
= hwif
->sg_table
;
652 if (hwif
->sg_mapped
) /* needed by ide-scsi */
655 if (rq
->cmd_type
!= REQ_TYPE_ATA_TASKFILE
) {
656 hwif
->sg_nents
= blk_rq_map_sg(drive
->queue
, rq
, sg
);
658 sg_init_one(sg
, rq
->buffer
, rq
->nr_sectors
* SECTOR_SIZE
);
663 EXPORT_SYMBOL_GPL(ide_map_sg
);
665 void ide_init_sg_cmd(ide_drive_t
*drive
, struct request
*rq
)
667 ide_hwif_t
*hwif
= drive
->hwif
;
669 hwif
->nsect
= hwif
->nleft
= rq
->nr_sectors
;
674 EXPORT_SYMBOL_GPL(ide_init_sg_cmd
);
677 * execute_drive_command - issue special drive command
678 * @drive: the drive to issue the command on
679 * @rq: the request structure holding the command
681 * execute_drive_cmd() issues a special drive command, usually
682 * initiated by ioctl() from the external hdparm program. The
683 * command can be a drive command, drive task or taskfile
684 * operation. Weirdly you can call it with NULL to wait for
685 * all commands to finish. Don't do this as that is due to change
688 static ide_startstop_t
execute_drive_cmd (ide_drive_t
*drive
,
691 ide_hwif_t
*hwif
= HWIF(drive
);
692 ide_task_t
*task
= rq
->special
;
695 hwif
->data_phase
= task
->data_phase
;
697 switch (hwif
->data_phase
) {
698 case TASKFILE_MULTI_OUT
:
700 case TASKFILE_MULTI_IN
:
702 ide_init_sg_cmd(drive
, rq
);
703 ide_map_sg(drive
, rq
);
708 return do_rw_taskfile(drive
, task
);
712 * NULL is actually a valid way of waiting for
713 * all current requests to be flushed from the queue.
716 printk("%s: DRIVE_CMD (null)\n", drive
->name
);
718 ide_end_drive_cmd(drive
, hwif
->tp_ops
->read_status(hwif
),
719 ide_read_error(drive
));
724 int ide_devset_execute(ide_drive_t
*drive
, const struct ide_devset
*setting
,
727 struct request_queue
*q
= drive
->queue
;
731 if (!(setting
->flags
& DS_SYNC
))
732 return setting
->set(drive
, arg
);
734 rq
= blk_get_request(q
, READ
, GFP_KERNEL
);
738 rq
->cmd_type
= REQ_TYPE_SPECIAL
;
740 rq
->cmd
[0] = REQ_DEVSET_EXEC
;
741 *(int *)&rq
->cmd
[1] = arg
;
742 rq
->special
= setting
->set
;
744 if (blk_execute_rq(q
, NULL
, rq
, 0))
750 EXPORT_SYMBOL_GPL(ide_devset_execute
);
752 static ide_startstop_t
ide_special_rq(ide_drive_t
*drive
, struct request
*rq
)
754 switch (rq
->cmd
[0]) {
755 case REQ_DEVSET_EXEC
:
757 int err
, (*setfunc
)(ide_drive_t
*, int) = rq
->special
;
759 err
= setfunc(drive
, *(int *)&rq
->cmd
[1]);
764 ide_end_request(drive
, err
, 0);
767 case REQ_DRIVE_RESET
:
768 return ide_do_reset(drive
);
770 blk_dump_rq_flags(rq
, "ide_special_rq - bad request");
771 ide_end_request(drive
, 0, 0);
776 static void ide_check_pm_state(ide_drive_t
*drive
, struct request
*rq
)
778 struct request_pm_state
*pm
= rq
->data
;
780 if (blk_pm_suspend_request(rq
) &&
781 pm
->pm_step
== ide_pm_state_start_suspend
)
782 /* Mark drive blocked when starting the suspend sequence. */
783 drive
->dev_flags
|= IDE_DFLAG_BLOCKED
;
784 else if (blk_pm_resume_request(rq
) &&
785 pm
->pm_step
== ide_pm_state_start_resume
) {
787 * The first thing we do on wakeup is to wait for BSY bit to
788 * go away (with a looong timeout) as a drive on this hwif may
789 * just be POSTing itself.
790 * We do that before even selecting as the "other" device on
791 * the bus may be broken enough to walk on our toes at this
794 ide_hwif_t
*hwif
= drive
->hwif
;
797 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive
->name
);
799 rc
= ide_wait_not_busy(hwif
, 35000);
801 printk(KERN_WARNING
"%s: bus not ready on wakeup\n", drive
->name
);
803 hwif
->tp_ops
->set_irq(hwif
, 1);
804 rc
= ide_wait_not_busy(hwif
, 100000);
806 printk(KERN_WARNING
"%s: drive not ready on wakeup\n", drive
->name
);
811 * start_request - start of I/O and command issuing for IDE
813 * start_request() initiates handling of a new I/O request. It
814 * accepts commands and I/O (read/write) requests.
816 * FIXME: this function needs a rename
819 static ide_startstop_t
start_request (ide_drive_t
*drive
, struct request
*rq
)
821 ide_startstop_t startstop
;
823 BUG_ON(!blk_rq_started(rq
));
826 printk("%s: start_request: current=0x%08lx\n",
827 HWIF(drive
)->name
, (unsigned long) rq
);
830 /* bail early if we've exceeded max_failures */
831 if (drive
->max_failures
&& (drive
->failures
> drive
->max_failures
)) {
832 rq
->cmd_flags
|= REQ_FAILED
;
836 if (blk_pm_request(rq
))
837 ide_check_pm_state(drive
, rq
);
840 if (ide_wait_stat(&startstop
, drive
, drive
->ready_stat
,
841 ATA_BUSY
| ATA_DRQ
, WAIT_READY
)) {
842 printk(KERN_ERR
"%s: drive not ready for command\n", drive
->name
);
845 if (!drive
->special
.all
) {
849 * We reset the drive so we need to issue a SETFEATURES.
850 * Do it _after_ do_special() restored device parameters.
852 if (drive
->current_speed
== 0xff)
853 ide_config_drive_speed(drive
, drive
->desired_speed
);
855 if (rq
->cmd_type
== REQ_TYPE_ATA_TASKFILE
)
856 return execute_drive_cmd(drive
, rq
);
857 else if (blk_pm_request(rq
)) {
858 struct request_pm_state
*pm
= rq
->data
;
860 printk("%s: start_power_step(step: %d)\n",
861 drive
->name
, rq
->pm
->pm_step
);
863 startstop
= ide_start_power_step(drive
, rq
);
864 if (startstop
== ide_stopped
&&
865 pm
->pm_step
== ide_pm_state_completed
)
866 ide_complete_pm_request(drive
, rq
);
868 } else if (!rq
->rq_disk
&& blk_special_request(rq
))
870 * TODO: Once all ULDs have been modified to
871 * check for specific op codes rather than
872 * blindly accepting any special request, the
873 * check for ->rq_disk above may be replaced
874 * by a more suitable mechanism or even
877 return ide_special_rq(drive
, rq
);
879 drv
= *(ide_driver_t
**)rq
->rq_disk
->private_data
;
881 return drv
->do_request(drive
, rq
, rq
->sector
);
883 return do_special(drive
);
885 ide_kill_rq(drive
, rq
);
890 * ide_stall_queue - pause an IDE device
891 * @drive: drive to stall
892 * @timeout: time to stall for (jiffies)
894 * ide_stall_queue() can be used by a drive to give excess bandwidth back
895 * to the hwgroup by sleeping for timeout jiffies.
898 void ide_stall_queue (ide_drive_t
*drive
, unsigned long timeout
)
900 if (timeout
> WAIT_WORSTCASE
)
901 timeout
= WAIT_WORSTCASE
;
902 drive
->sleep
= timeout
+ jiffies
;
903 drive
->dev_flags
|= IDE_DFLAG_SLEEPING
;
906 EXPORT_SYMBOL(ide_stall_queue
);
908 #define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
911 * choose_drive - select a drive to service
912 * @hwgroup: hardware group to select on
914 * choose_drive() selects the next drive which will be serviced.
915 * This is necessary because the IDE layer can't issue commands
916 * to both drives on the same cable, unlike SCSI.
919 static inline ide_drive_t
*choose_drive (ide_hwgroup_t
*hwgroup
)
921 ide_drive_t
*drive
, *best
;
925 drive
= hwgroup
->drive
;
928 * drive is doing pre-flush, ordered write, post-flush sequence. even
929 * though that is 3 requests, it must be seen as a single transaction.
930 * we must not preempt this drive until that is complete
932 if (blk_queue_flushing(drive
->queue
)) {
934 * small race where queue could get replugged during
935 * the 3-request flush cycle, just yank the plug since
936 * we want it to finish asap
938 blk_remove_plug(drive
->queue
);
943 u8 dev_s
= !!(drive
->dev_flags
& IDE_DFLAG_SLEEPING
);
944 u8 best_s
= (best
&& !!(best
->dev_flags
& IDE_DFLAG_SLEEPING
));
946 if ((dev_s
== 0 || time_after_eq(jiffies
, drive
->sleep
)) &&
947 !elv_queue_empty(drive
->queue
)) {
949 (dev_s
&& (best_s
== 0 || time_before(drive
->sleep
, best
->sleep
))) ||
950 (best_s
== 0 && time_before(WAKEUP(drive
), WAKEUP(best
)))) {
951 if (!blk_queue_plugged(drive
->queue
))
955 } while ((drive
= drive
->next
) != hwgroup
->drive
);
957 if (best
&& (best
->dev_flags
& IDE_DFLAG_NICE1
) &&
958 (best
->dev_flags
& IDE_DFLAG_SLEEPING
) == 0 &&
959 best
!= hwgroup
->drive
&& best
->service_time
> WAIT_MIN_SLEEP
) {
960 long t
= (signed long)(WAKEUP(best
) - jiffies
);
961 if (t
>= WAIT_MIN_SLEEP
) {
963 * We *may* have some time to spare, but first let's see if
964 * someone can potentially benefit from our nice mood today..
968 if ((drive
->dev_flags
& IDE_DFLAG_SLEEPING
) == 0
969 && time_before(jiffies
- best
->service_time
, WAKEUP(drive
))
970 && time_before(WAKEUP(drive
), jiffies
+ t
))
972 ide_stall_queue(best
, min_t(long, t
, 10 * WAIT_MIN_SLEEP
));
975 } while ((drive
= drive
->next
) != best
);
982 * Issue a new request to a drive from hwgroup
983 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
985 * A hwgroup is a serialized group of IDE interfaces. Usually there is
986 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
987 * may have both interfaces in a single hwgroup to "serialize" access.
988 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
989 * together into one hwgroup for serialized access.
991 * Note also that several hwgroups can end up sharing a single IRQ,
992 * possibly along with many other devices. This is especially common in
993 * PCI-based systems with off-board IDE controller cards.
995 * The IDE driver uses the single global ide_lock spinlock to protect
996 * access to the request queues, and to protect the hwgroup->busy flag.
998 * The first thread into the driver for a particular hwgroup sets the
999 * hwgroup->busy flag to indicate that this hwgroup is now active,
1000 * and then initiates processing of the top request from the request queue.
1002 * Other threads attempting entry notice the busy setting, and will simply
1003 * queue their new requests and exit immediately. Note that hwgroup->busy
1004 * remains set even when the driver is merely awaiting the next interrupt.
1005 * Thus, the meaning is "this hwgroup is busy processing a request".
1007 * When processing of a request completes, the completing thread or IRQ-handler
1008 * will start the next request from the queue. If no more work remains,
1009 * the driver will clear the hwgroup->busy flag and exit.
1011 * The ide_lock (spinlock) is used to protect all access to the
1012 * hwgroup->busy flag, but is otherwise not needed for most processing in
1013 * the driver. This makes the driver much more friendlier to shared IRQs
1014 * than previous designs, while remaining 100% (?) SMP safe and capable.
1016 static void ide_do_request (ide_hwgroup_t
*hwgroup
, int masked_irq
)
1021 ide_startstop_t startstop
;
1024 /* for atari only: POSSIBLY BROKEN HERE(?) */
1025 ide_get_lock(ide_intr
, hwgroup
);
1027 /* caller must own ide_lock */
1028 BUG_ON(!irqs_disabled());
1030 while (!hwgroup
->busy
) {
1032 drive
= choose_drive(hwgroup
);
1033 if (drive
== NULL
) {
1035 unsigned long sleep
= 0; /* shut up, gcc */
1037 drive
= hwgroup
->drive
;
1039 if ((drive
->dev_flags
& IDE_DFLAG_SLEEPING
) &&
1041 time_before(drive
->sleep
, sleep
))) {
1043 sleep
= drive
->sleep
;
1045 } while ((drive
= drive
->next
) != hwgroup
->drive
);
1048 * Take a short snooze, and then wake up this hwgroup again.
1049 * This gives other hwgroups on the same a chance to
1050 * play fairly with us, just in case there are big differences
1051 * in relative throughputs.. don't want to hog the cpu too much.
1053 if (time_before(sleep
, jiffies
+ WAIT_MIN_SLEEP
))
1054 sleep
= jiffies
+ WAIT_MIN_SLEEP
;
1056 if (timer_pending(&hwgroup
->timer
))
1057 printk(KERN_CRIT
"ide_set_handler: timer already active\n");
1059 /* so that ide_timer_expiry knows what to do */
1060 hwgroup
->sleeping
= 1;
1061 hwgroup
->req_gen_timer
= hwgroup
->req_gen
;
1062 mod_timer(&hwgroup
->timer
, sleep
);
1063 /* we purposely leave hwgroup->busy==1
1066 /* Ugly, but how can we sleep for the lock
1067 * otherwise? perhaps from tq_disk?
1070 /* for atari only */
1075 /* no more work for this hwgroup (for now) */
1080 if (hwgroup
->hwif
->sharing_irq
&& hwif
!= hwgroup
->hwif
) {
1082 * set nIEN for previous hwif, drives in the
1083 * quirk_list may not like intr setups/cleanups
1085 if (drive
->quirk_list
!= 1)
1086 hwif
->tp_ops
->set_irq(hwif
, 0);
1088 hwgroup
->hwif
= hwif
;
1089 hwgroup
->drive
= drive
;
1090 drive
->dev_flags
&= ~IDE_DFLAG_SLEEPING
;
1091 drive
->service_start
= jiffies
;
1093 if (blk_queue_plugged(drive
->queue
)) {
1094 printk(KERN_ERR
"ide: huh? queue was plugged!\n");
1099 * we know that the queue isn't empty, but this can happen
1100 * if the q->prep_rq_fn() decides to kill a request
1102 rq
= elv_next_request(drive
->queue
);
1109 * Sanity: don't accept a request that isn't a PM request
1110 * if we are currently power managed. This is very important as
1111 * blk_stop_queue() doesn't prevent the elv_next_request()
1112 * above to return us whatever is in the queue. Since we call
1113 * ide_do_request() ourselves, we end up taking requests while
1114 * the queue is blocked...
1116 * We let requests forced at head of queue with ide-preempt
1117 * though. I hope that doesn't happen too much, hopefully not
1118 * unless the subdriver triggers such a thing in its own PM
1121 * We count how many times we loop here to make sure we service
1122 * all drives in the hwgroup without looping for ever
1124 if ((drive
->dev_flags
& IDE_DFLAG_BLOCKED
) &&
1125 blk_pm_request(rq
) == 0 &&
1126 (rq
->cmd_flags
& REQ_PREEMPT
) == 0) {
1127 drive
= drive
->next
? drive
->next
: hwgroup
->drive
;
1128 if (loops
++ < 4 && !blk_queue_plugged(drive
->queue
))
1130 /* We clear busy, there should be no pending ATA command at this point. */
1138 * Some systems have trouble with IDE IRQs arriving while
1139 * the driver is still setting things up. So, here we disable
1140 * the IRQ used by this interface while the request is being started.
1141 * This may look bad at first, but pretty much the same thing
1142 * happens anyway when any interrupt comes in, IDE or otherwise
1143 * -- the kernel masks the IRQ while it is being handled.
1145 if (masked_irq
!= IDE_NO_IRQ
&& hwif
->irq
!= masked_irq
)
1146 disable_irq_nosync(hwif
->irq
);
1147 spin_unlock(&ide_lock
);
1148 local_irq_enable_in_hardirq();
1149 /* allow other IRQs while we start this request */
1150 startstop
= start_request(drive
, rq
);
1151 spin_lock_irq(&ide_lock
);
1152 if (masked_irq
!= IDE_NO_IRQ
&& hwif
->irq
!= masked_irq
)
1153 enable_irq(hwif
->irq
);
1154 if (startstop
== ide_stopped
)
1160 * Passes the stuff to ide_do_request
1162 void do_ide_request(struct request_queue
*q
)
1164 ide_drive_t
*drive
= q
->queuedata
;
1166 ide_do_request(HWGROUP(drive
), IDE_NO_IRQ
);
1170 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1171 * retry the current request in pio mode instead of risking tossing it
1174 static ide_startstop_t
ide_dma_timeout_retry(ide_drive_t
*drive
, int error
)
1176 ide_hwif_t
*hwif
= HWIF(drive
);
1178 ide_startstop_t ret
= ide_stopped
;
1181 * end current dma transaction
1185 printk(KERN_WARNING
"%s: DMA timeout error\n", drive
->name
);
1186 (void)hwif
->dma_ops
->dma_end(drive
);
1187 ret
= ide_error(drive
, "dma timeout error",
1188 hwif
->tp_ops
->read_status(hwif
));
1190 printk(KERN_WARNING
"%s: DMA timeout retry\n", drive
->name
);
1191 hwif
->dma_ops
->dma_timeout(drive
);
1195 * disable dma for now, but remember that we did so because of
1196 * a timeout -- we'll reenable after we finish this next request
1197 * (or rather the first chunk of it) in pio.
1199 drive
->dev_flags
|= IDE_DFLAG_DMA_PIO_RETRY
;
1201 ide_dma_off_quietly(drive
);
1204 * un-busy drive etc (hwgroup->busy is cleared on return) and
1205 * make sure request is sane
1207 rq
= HWGROUP(drive
)->rq
;
1212 HWGROUP(drive
)->rq
= NULL
;
1219 rq
->sector
= rq
->bio
->bi_sector
;
1220 rq
->current_nr_sectors
= bio_iovec(rq
->bio
)->bv_len
>> 9;
1221 rq
->hard_cur_sectors
= rq
->current_nr_sectors
;
1222 rq
->buffer
= bio_data(rq
->bio
);
1228 * ide_timer_expiry - handle lack of an IDE interrupt
1229 * @data: timer callback magic (hwgroup)
1231 * An IDE command has timed out before the expected drive return
1232 * occurred. At this point we attempt to clean up the current
1233 * mess. If the current handler includes an expiry handler then
1234 * we invoke the expiry handler, and providing it is happy the
1235 * work is done. If that fails we apply generic recovery rules
1236 * invoking the handler and checking the drive DMA status. We
1237 * have an excessively incestuous relationship with the DMA
1238 * logic that wants cleaning up.
1241 void ide_timer_expiry (unsigned long data
)
1243 ide_hwgroup_t
*hwgroup
= (ide_hwgroup_t
*) data
;
1244 ide_handler_t
*handler
;
1245 ide_expiry_t
*expiry
;
1246 unsigned long flags
;
1247 unsigned long wait
= -1;
1249 spin_lock_irqsave(&ide_lock
, flags
);
1251 if (((handler
= hwgroup
->handler
) == NULL
) ||
1252 (hwgroup
->req_gen
!= hwgroup
->req_gen_timer
)) {
1254 * Either a marginal timeout occurred
1255 * (got the interrupt just as timer expired),
1256 * or we were "sleeping" to give other devices a chance.
1257 * Either way, we don't really want to complain about anything.
1259 if (hwgroup
->sleeping
) {
1260 hwgroup
->sleeping
= 0;
1264 ide_drive_t
*drive
= hwgroup
->drive
;
1266 printk(KERN_ERR
"ide_timer_expiry: hwgroup->drive was NULL\n");
1267 hwgroup
->handler
= NULL
;
1270 ide_startstop_t startstop
= ide_stopped
;
1271 if (!hwgroup
->busy
) {
1272 hwgroup
->busy
= 1; /* paranoia */
1273 printk(KERN_ERR
"%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive
->name
);
1275 if ((expiry
= hwgroup
->expiry
) != NULL
) {
1277 if ((wait
= expiry(drive
)) > 0) {
1279 hwgroup
->timer
.expires
= jiffies
+ wait
;
1280 hwgroup
->req_gen_timer
= hwgroup
->req_gen
;
1281 add_timer(&hwgroup
->timer
);
1282 spin_unlock_irqrestore(&ide_lock
, flags
);
1286 hwgroup
->handler
= NULL
;
1288 * We need to simulate a real interrupt when invoking
1289 * the handler() function, which means we need to
1290 * globally mask the specific IRQ:
1292 spin_unlock(&ide_lock
);
1294 /* disable_irq_nosync ?? */
1295 disable_irq(hwif
->irq
);
1297 * as if we were handling an interrupt */
1298 local_irq_disable();
1299 if (hwgroup
->polling
) {
1300 startstop
= handler(drive
);
1301 } else if (drive_is_ready(drive
)) {
1302 if (drive
->waiting_for_dma
)
1303 hwif
->dma_ops
->dma_lost_irq(drive
);
1304 (void)ide_ack_intr(hwif
);
1305 printk(KERN_WARNING
"%s: lost interrupt\n", drive
->name
);
1306 startstop
= handler(drive
);
1308 if (drive
->waiting_for_dma
) {
1309 startstop
= ide_dma_timeout_retry(drive
, wait
);
1312 ide_error(drive
, "irq timeout",
1313 hwif
->tp_ops
->read_status(hwif
));
1315 drive
->service_time
= jiffies
- drive
->service_start
;
1316 spin_lock_irq(&ide_lock
);
1317 enable_irq(hwif
->irq
);
1318 if (startstop
== ide_stopped
)
1322 ide_do_request(hwgroup
, IDE_NO_IRQ
);
1323 spin_unlock_irqrestore(&ide_lock
, flags
);
1327 * unexpected_intr - handle an unexpected IDE interrupt
1328 * @irq: interrupt line
1329 * @hwgroup: hwgroup being processed
1331 * There's nothing really useful we can do with an unexpected interrupt,
1332 * other than reading the status register (to clear it), and logging it.
1333 * There should be no way that an irq can happen before we're ready for it,
1334 * so we needn't worry much about losing an "important" interrupt here.
1336 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1337 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1338 * looks "good", we just ignore the interrupt completely.
1340 * This routine assumes __cli() is in effect when called.
1342 * If an unexpected interrupt happens on irq15 while we are handling irq14
1343 * and if the two interfaces are "serialized" (CMD640), then it looks like
1344 * we could screw up by interfering with a new request being set up for
1347 * In reality, this is a non-issue. The new command is not sent unless
1348 * the drive is ready to accept one, in which case we know the drive is
1349 * not trying to interrupt us. And ide_set_handler() is always invoked
1350 * before completing the issuance of any new drive command, so we will not
1351 * be accidentally invoked as a result of any valid command completion
1354 * Note that we must walk the entire hwgroup here. We know which hwif
1355 * is doing the current command, but we don't know which hwif burped
1359 static void unexpected_intr (int irq
, ide_hwgroup_t
*hwgroup
)
1362 ide_hwif_t
*hwif
= hwgroup
->hwif
;
1365 * handle the unexpected interrupt
1368 if (hwif
->irq
== irq
) {
1369 stat
= hwif
->tp_ops
->read_status(hwif
);
1371 if (!OK_STAT(stat
, ATA_DRDY
, BAD_STAT
)) {
1372 /* Try to not flood the console with msgs */
1373 static unsigned long last_msgtime
, count
;
1375 if (time_after(jiffies
, last_msgtime
+ HZ
)) {
1376 last_msgtime
= jiffies
;
1377 printk(KERN_ERR
"%s%s: unexpected interrupt, "
1378 "status=0x%02x, count=%ld\n",
1380 (hwif
->next
==hwgroup
->hwif
) ? "" : "(?)", stat
, count
);
1384 } while ((hwif
= hwif
->next
) != hwgroup
->hwif
);
1388 * ide_intr - default IDE interrupt handler
1389 * @irq: interrupt number
1390 * @dev_id: hwif group
1391 * @regs: unused weirdness from the kernel irq layer
1393 * This is the default IRQ handler for the IDE layer. You should
1394 * not need to override it. If you do be aware it is subtle in
1397 * hwgroup->hwif is the interface in the group currently performing
1398 * a command. hwgroup->drive is the drive and hwgroup->handler is
1399 * the IRQ handler to call. As we issue a command the handlers
1400 * step through multiple states, reassigning the handler to the
1401 * next step in the process. Unlike a smart SCSI controller IDE
1402 * expects the main processor to sequence the various transfer
1403 * stages. We also manage a poll timer to catch up with most
1404 * timeout situations. There are still a few where the handlers
1405 * don't ever decide to give up.
1407 * The handler eventually returns ide_stopped to indicate the
1408 * request completed. At this point we issue the next request
1409 * on the hwgroup and the process begins again.
1412 irqreturn_t
ide_intr (int irq
, void *dev_id
)
1414 unsigned long flags
;
1415 ide_hwgroup_t
*hwgroup
= (ide_hwgroup_t
*)dev_id
;
1418 ide_handler_t
*handler
;
1419 ide_startstop_t startstop
;
1421 spin_lock_irqsave(&ide_lock
, flags
);
1422 hwif
= hwgroup
->hwif
;
1424 if (!ide_ack_intr(hwif
)) {
1425 spin_unlock_irqrestore(&ide_lock
, flags
);
1429 if ((handler
= hwgroup
->handler
) == NULL
|| hwgroup
->polling
) {
1431 * Not expecting an interrupt from this drive.
1432 * That means this could be:
1433 * (1) an interrupt from another PCI device
1434 * sharing the same PCI INT# as us.
1435 * or (2) a drive just entered sleep or standby mode,
1436 * and is interrupting to let us know.
1437 * or (3) a spurious interrupt of unknown origin.
1439 * For PCI, we cannot tell the difference,
1440 * so in that case we just ignore it and hope it goes away.
1442 * FIXME: unexpected_intr should be hwif-> then we can
1443 * remove all the ifdef PCI crap
1445 #ifdef CONFIG_BLK_DEV_IDEPCI
1446 if (hwif
->chipset
!= ide_pci
)
1447 #endif /* CONFIG_BLK_DEV_IDEPCI */
1450 * Probably not a shared PCI interrupt,
1451 * so we can safely try to do something about it:
1453 unexpected_intr(irq
, hwgroup
);
1454 #ifdef CONFIG_BLK_DEV_IDEPCI
1457 * Whack the status register, just in case
1458 * we have a leftover pending IRQ.
1460 (void)hwif
->tp_ops
->read_status(hwif
);
1461 #endif /* CONFIG_BLK_DEV_IDEPCI */
1463 spin_unlock_irqrestore(&ide_lock
, flags
);
1466 drive
= hwgroup
->drive
;
1469 * This should NEVER happen, and there isn't much
1470 * we could do about it here.
1472 * [Note - this can occur if the drive is hot unplugged]
1474 spin_unlock_irqrestore(&ide_lock
, flags
);
1477 if (!drive_is_ready(drive
)) {
1479 * This happens regularly when we share a PCI IRQ with
1480 * another device. Unfortunately, it can also happen
1481 * with some buggy drives that trigger the IRQ before
1482 * their status register is up to date. Hopefully we have
1483 * enough advance overhead that the latter isn't a problem.
1485 spin_unlock_irqrestore(&ide_lock
, flags
);
1488 if (!hwgroup
->busy
) {
1489 hwgroup
->busy
= 1; /* paranoia */
1490 printk(KERN_ERR
"%s: ide_intr: hwgroup->busy was 0 ??\n", drive
->name
);
1492 hwgroup
->handler
= NULL
;
1494 del_timer(&hwgroup
->timer
);
1495 spin_unlock(&ide_lock
);
1497 /* Some controllers might set DMA INTR no matter DMA or PIO;
1498 * bmdma status might need to be cleared even for
1499 * PIO interrupts to prevent spurious/lost irq.
1501 if (hwif
->ide_dma_clear_irq
&& !(drive
->waiting_for_dma
))
1502 /* ide_dma_end() needs bmdma status for error checking.
1503 * So, skip clearing bmdma status here and leave it
1504 * to ide_dma_end() if this is dma interrupt.
1506 hwif
->ide_dma_clear_irq(drive
);
1508 if (drive
->dev_flags
& IDE_DFLAG_UNMASK
)
1509 local_irq_enable_in_hardirq();
1510 /* service this interrupt, may set handler for next interrupt */
1511 startstop
= handler(drive
);
1512 spin_lock_irq(&ide_lock
);
1515 * Note that handler() may have set things up for another
1516 * interrupt to occur soon, but it cannot happen until
1517 * we exit from this routine, because it will be the
1518 * same irq as is currently being serviced here, and Linux
1519 * won't allow another of the same (on any CPU) until we return.
1521 drive
->service_time
= jiffies
- drive
->service_start
;
1522 if (startstop
== ide_stopped
) {
1523 if (hwgroup
->handler
== NULL
) { /* paranoia */
1525 ide_do_request(hwgroup
, hwif
->irq
);
1527 printk(KERN_ERR
"%s: ide_intr: huh? expected NULL handler "
1528 "on exit\n", drive
->name
);
1531 spin_unlock_irqrestore(&ide_lock
, flags
);
1536 * ide_do_drive_cmd - issue IDE special command
1537 * @drive: device to issue command
1538 * @rq: request to issue
1540 * This function issues a special IDE device request
1541 * onto the request queue.
1543 * the rq is queued at the head of the request queue, displacing
1544 * the currently-being-processed request and this function
1545 * returns immediately without waiting for the new rq to be
1546 * completed. This is VERY DANGEROUS, and is intended for
1547 * careful use by the ATAPI tape/cdrom driver code.
1550 void ide_do_drive_cmd(ide_drive_t
*drive
, struct request
*rq
)
1552 unsigned long flags
;
1553 ide_hwgroup_t
*hwgroup
= HWGROUP(drive
);
1555 spin_lock_irqsave(&ide_lock
, flags
);
1557 __elv_add_request(drive
->queue
, rq
, ELEVATOR_INSERT_FRONT
, 1);
1558 __generic_unplug_device(drive
->queue
);
1559 spin_unlock_irqrestore(&ide_lock
, flags
);
1562 EXPORT_SYMBOL(ide_do_drive_cmd
);
1564 void ide_pktcmd_tf_load(ide_drive_t
*drive
, u32 tf_flags
, u16 bcount
, u8 dma
)
1566 ide_hwif_t
*hwif
= drive
->hwif
;
1569 memset(&task
, 0, sizeof(task
));
1570 task
.tf_flags
= IDE_TFLAG_OUT_LBAH
| IDE_TFLAG_OUT_LBAM
|
1571 IDE_TFLAG_OUT_FEATURE
| tf_flags
;
1572 task
.tf
.feature
= dma
; /* Use PIO/DMA */
1573 task
.tf
.lbam
= bcount
& 0xff;
1574 task
.tf
.lbah
= (bcount
>> 8) & 0xff;
1576 ide_tf_dump(drive
->name
, &task
.tf
);
1577 hwif
->tp_ops
->set_irq(hwif
, 1);
1578 SELECT_MASK(drive
, 0);
1579 hwif
->tp_ops
->tf_load(drive
, &task
);
1582 EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load
);
1584 void ide_pad_transfer(ide_drive_t
*drive
, int write
, int len
)
1586 ide_hwif_t
*hwif
= drive
->hwif
;
1591 hwif
->tp_ops
->output_data(drive
, NULL
, buf
, min(4, len
));
1593 hwif
->tp_ops
->input_data(drive
, NULL
, buf
, min(4, len
));
1597 EXPORT_SYMBOL_GPL(ide_pad_transfer
);