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/completion.h>
44 #include <linux/reboot.h>
45 #include <linux/cdrom.h>
46 #include <linux/seq_file.h>
47 #include <linux/device.h>
48 #include <linux/kmod.h>
49 #include <linux/scatterlist.h>
50 #include <linux/bitops.h>
52 #include <asm/byteorder.h>
54 #include <asm/uaccess.h>
57 static int __ide_end_request(ide_drive_t *drive, struct request *rq,
58 int uptodate, unsigned int nr_bytes, int dequeue)
63 * if failfast is set on a request, override number of sectors and
64 * complete the whole request right now
66 if (blk_noretry_request(rq) && end_io_error(uptodate))
67 nr_bytes = rq->hard_nr_sectors << 9;
69 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
73 * decide whether to reenable DMA -- 3 is a random magic for now,
74 * if we DMA timeout more than 3 times, just stay in PIO
76 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
81 if (!end_that_request_chunk(rq, uptodate, nr_bytes)) {
82 add_disk_randomness(rq->rq_disk);
84 if (!list_empty(&rq->queuelist))
85 blkdev_dequeue_request(rq);
86 HWGROUP(drive)->rq = NULL;
88 end_that_request_last(rq, uptodate);
96 * ide_end_request - complete an IDE I/O
97 * @drive: IDE device for the I/O
99 * @nr_sectors: number of sectors completed
101 * This is our end_request wrapper function. We complete the I/O
102 * update random number input and dequeue the request, which if
103 * it was tagged may be out of order.
106 int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
108 unsigned int nr_bytes = nr_sectors << 9;
114 * room for locking improvements here, the calls below don't
115 * need the queue lock held at all
117 spin_lock_irqsave(&ide_lock, flags);
118 rq = HWGROUP(drive)->rq;
121 if (blk_pc_request(rq))
122 nr_bytes = rq->data_len;
124 nr_bytes = rq->hard_cur_sectors << 9;
127 ret = __ide_end_request(drive, rq, uptodate, nr_bytes, 1);
129 spin_unlock_irqrestore(&ide_lock, flags);
132 EXPORT_SYMBOL(ide_end_request);
135 * Power Management state machine. This one is rather trivial for now,
136 * we should probably add more, like switching back to PIO on suspend
137 * to help some BIOSes, re-do the door locking on resume, etc...
141 ide_pm_flush_cache = ide_pm_state_start_suspend,
144 idedisk_pm_restore_pio = ide_pm_state_start_resume,
149 static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error)
151 struct request_pm_state *pm = rq->data;
153 if (drive->media != ide_disk)
156 switch (pm->pm_step) {
157 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */
158 if (pm->pm_state == PM_EVENT_FREEZE)
159 pm->pm_step = ide_pm_state_completed;
161 pm->pm_step = idedisk_pm_standby;
163 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */
164 pm->pm_step = ide_pm_state_completed;
166 case idedisk_pm_restore_pio: /* Resume step 1 complete */
167 pm->pm_step = idedisk_pm_idle;
169 case idedisk_pm_idle: /* Resume step 2 (idle) complete */
170 pm->pm_step = ide_pm_restore_dma;
175 static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq)
177 struct request_pm_state *pm = rq->data;
178 ide_task_t *args = rq->special;
180 memset(args, 0, sizeof(*args));
182 switch (pm->pm_step) {
183 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */
184 if (drive->media != ide_disk)
186 /* Not supported? Switch to next step now. */
187 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) {
188 ide_complete_power_step(drive, rq, 0, 0);
191 if (ide_id_has_flush_cache_ext(drive->id))
192 args->tf.command = WIN_FLUSH_CACHE_EXT;
194 args->tf.command = WIN_FLUSH_CACHE;
197 case idedisk_pm_standby: /* Suspend step 2 (standby) */
198 args->tf.command = WIN_STANDBYNOW1;
201 case idedisk_pm_restore_pio: /* Resume step 1 (restore PIO) */
202 ide_set_max_pio(drive);
204 * skip idedisk_pm_idle for ATAPI devices
206 if (drive->media != ide_disk)
207 pm->pm_step = ide_pm_restore_dma;
209 ide_complete_power_step(drive, rq, 0, 0);
212 case idedisk_pm_idle: /* Resume step 2 (idle) */
213 args->tf.command = WIN_IDLEIMMEDIATE;
216 case ide_pm_restore_dma: /* Resume step 3 (restore DMA) */
218 * Right now, all we do is call ide_set_dma(drive),
219 * we could be smarter and check for current xfer_speed
220 * in struct drive etc...
222 if (drive->hwif->dma_host_set == NULL)
225 * TODO: respect ->using_dma setting
230 pm->pm_step = ide_pm_state_completed;
234 args->tf_flags = IDE_TFLAG_OUT_TF | IDE_TFLAG_OUT_DEVICE;
235 args->data_phase = TASKFILE_NO_DATA;
236 return do_rw_taskfile(drive, args);
240 * ide_end_dequeued_request - complete an IDE I/O
241 * @drive: IDE device for the I/O
243 * @nr_sectors: number of sectors completed
245 * Complete an I/O that is no longer on the request queue. This
246 * typically occurs when we pull the request and issue a REQUEST_SENSE.
247 * We must still finish the old request but we must not tamper with the
248 * queue in the meantime.
250 * NOTE: This path does not handle barrier, but barrier is not supported
254 int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
255 int uptodate, int nr_sectors)
260 spin_lock_irqsave(&ide_lock, flags);
261 BUG_ON(!blk_rq_started(rq));
262 ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0);
263 spin_unlock_irqrestore(&ide_lock, flags);
267 EXPORT_SYMBOL_GPL(ide_end_dequeued_request);
271 * ide_complete_pm_request - end the current Power Management request
272 * @drive: target drive
275 * This function cleans up the current PM request and stops the queue
278 static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
283 printk("%s: completing PM request, %s\n", drive->name,
284 blk_pm_suspend_request(rq) ? "suspend" : "resume");
286 spin_lock_irqsave(&ide_lock, flags);
287 if (blk_pm_suspend_request(rq)) {
288 blk_stop_queue(drive->queue);
291 blk_start_queue(drive->queue);
293 blkdev_dequeue_request(rq);
294 HWGROUP(drive)->rq = NULL;
295 end_that_request_last(rq, 1);
296 spin_unlock_irqrestore(&ide_lock, flags);
299 void ide_tf_read(ide_drive_t *drive, ide_task_t *task)
301 ide_hwif_t *hwif = drive->hwif;
302 struct ide_taskfile *tf = &task->tf;
304 if (task->tf_flags & IDE_TFLAG_IN_DATA) {
305 u16 data = hwif->INW(IDE_DATA_REG);
307 tf->data = data & 0xff;
308 tf->hob_data = (data >> 8) & 0xff;
311 /* be sure we're looking at the low order bits */
312 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG);
314 if (task->tf_flags & IDE_TFLAG_IN_NSECT)
315 tf->nsect = hwif->INB(IDE_NSECTOR_REG);
316 if (task->tf_flags & IDE_TFLAG_IN_LBAL)
317 tf->lbal = hwif->INB(IDE_SECTOR_REG);
318 if (task->tf_flags & IDE_TFLAG_IN_LBAM)
319 tf->lbam = hwif->INB(IDE_LCYL_REG);
320 if (task->tf_flags & IDE_TFLAG_IN_LBAH)
321 tf->lbah = hwif->INB(IDE_HCYL_REG);
322 if (task->tf_flags & IDE_TFLAG_IN_DEVICE)
323 tf->device = hwif->INB(IDE_SELECT_REG);
325 if (task->tf_flags & IDE_TFLAG_LBA48) {
326 hwif->OUTB(drive->ctl | 0x80, IDE_CONTROL_REG);
328 if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE)
329 tf->hob_feature = hwif->INB(IDE_FEATURE_REG);
330 if (task->tf_flags & IDE_TFLAG_IN_HOB_NSECT)
331 tf->hob_nsect = hwif->INB(IDE_NSECTOR_REG);
332 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAL)
333 tf->hob_lbal = hwif->INB(IDE_SECTOR_REG);
334 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAM)
335 tf->hob_lbam = hwif->INB(IDE_LCYL_REG);
336 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAH)
337 tf->hob_lbah = hwif->INB(IDE_HCYL_REG);
342 * ide_end_drive_cmd - end an explicit drive command
347 * Clean up after success/failure of an explicit drive command.
348 * These get thrown onto the queue so they are synchronized with
349 * real I/O operations on the drive.
351 * In LBA48 mode we have to read the register set twice to get
352 * all the extra information out.
355 void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
357 ide_hwif_t *hwif = HWIF(drive);
361 spin_lock_irqsave(&ide_lock, flags);
362 rq = HWGROUP(drive)->rq;
363 spin_unlock_irqrestore(&ide_lock, flags);
365 if (rq->cmd_type == REQ_TYPE_ATA_CMD) {
366 u8 *args = (u8 *) rq->buffer;
368 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
373 args[2] = hwif->INB(IDE_NSECTOR_REG);
375 } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
376 ide_task_t *args = (ide_task_t *) rq->special;
378 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
381 struct ide_taskfile *tf = &args->tf;
386 args->tf_flags |= (IDE_TFLAG_IN_TF|IDE_TFLAG_IN_DEVICE);
387 if (args->tf_flags & IDE_TFLAG_LBA48)
388 args->tf_flags |= IDE_TFLAG_IN_HOB;
390 ide_tf_read(drive, args);
392 } else if (blk_pm_request(rq)) {
393 struct request_pm_state *pm = rq->data;
395 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
396 drive->name, rq->pm->pm_step, stat, err);
398 ide_complete_power_step(drive, rq, stat, err);
399 if (pm->pm_step == ide_pm_state_completed)
400 ide_complete_pm_request(drive, rq);
404 spin_lock_irqsave(&ide_lock, flags);
405 blkdev_dequeue_request(rq);
406 HWGROUP(drive)->rq = NULL;
408 end_that_request_last(rq, !rq->errors);
409 spin_unlock_irqrestore(&ide_lock, flags);
412 EXPORT_SYMBOL(ide_end_drive_cmd);
415 * try_to_flush_leftover_data - flush junk
416 * @drive: drive to flush
418 * try_to_flush_leftover_data() is invoked in response to a drive
419 * unexpectedly having its DRQ_STAT bit set. As an alternative to
420 * resetting the drive, this routine tries to clear the condition
421 * by read a sector's worth of data from the drive. Of course,
422 * this may not help if the drive is *waiting* for data from *us*.
424 static void try_to_flush_leftover_data (ide_drive_t *drive)
426 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;
428 if (drive->media != ide_disk)
432 u32 wcount = (i > 16) ? 16 : i;
435 HWIF(drive)->ata_input_data(drive, buffer, wcount);
439 static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
444 drv = *(ide_driver_t **)rq->rq_disk->private_data;
445 drv->end_request(drive, 0, 0);
447 ide_end_request(drive, 0, 0);
450 static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
452 ide_hwif_t *hwif = drive->hwif;
454 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
455 /* other bits are useless when BUSY */
456 rq->errors |= ERROR_RESET;
457 } else if (stat & ERR_STAT) {
458 /* err has different meaning on cdrom and tape */
459 if (err == ABRT_ERR) {
460 if (drive->select.b.lba &&
461 /* some newer drives don't support WIN_SPECIFY */
462 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY)
464 } else if ((err & BAD_CRC) == BAD_CRC) {
465 /* UDMA crc error, just retry the operation */
467 } else if (err & (BBD_ERR | ECC_ERR)) {
468 /* retries won't help these */
469 rq->errors = ERROR_MAX;
470 } else if (err & TRK0_ERR) {
471 /* help it find track zero */
472 rq->errors |= ERROR_RECAL;
476 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ &&
477 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0)
478 try_to_flush_leftover_data(drive);
480 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) {
481 ide_kill_rq(drive, rq);
485 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
486 rq->errors |= ERROR_RESET;
488 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
490 return ide_do_reset(drive);
493 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
494 drive->special.b.recalibrate = 1;
501 static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
503 ide_hwif_t *hwif = drive->hwif;
505 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
506 /* other bits are useless when BUSY */
507 rq->errors |= ERROR_RESET;
509 /* add decoding error stuff */
512 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT))
514 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
516 if (rq->errors >= ERROR_MAX) {
517 ide_kill_rq(drive, rq);
519 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
521 return ide_do_reset(drive);
530 __ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
532 if (drive->media == ide_disk)
533 return ide_ata_error(drive, rq, stat, err);
534 return ide_atapi_error(drive, rq, stat, err);
537 EXPORT_SYMBOL_GPL(__ide_error);
540 * ide_error - handle an error on the IDE
541 * @drive: drive the error occurred on
542 * @msg: message to report
545 * ide_error() takes action based on the error returned by the drive.
546 * For normal I/O that may well include retries. We deal with
547 * both new-style (taskfile) and old style command handling here.
548 * In the case of taskfile command handling there is work left to
552 ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
557 err = ide_dump_status(drive, msg, stat);
559 if ((rq = HWGROUP(drive)->rq) == NULL)
562 /* retry only "normal" I/O: */
563 if (!blk_fs_request(rq)) {
565 ide_end_drive_cmd(drive, stat, err);
572 drv = *(ide_driver_t **)rq->rq_disk->private_data;
573 return drv->error(drive, rq, stat, err);
575 return __ide_error(drive, rq, stat, err);
578 EXPORT_SYMBOL_GPL(ide_error);
580 ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
582 if (drive->media != ide_disk)
583 rq->errors |= ERROR_RESET;
585 ide_kill_rq(drive, rq);
590 EXPORT_SYMBOL_GPL(__ide_abort);
593 * ide_abort - abort pending IDE operations
594 * @drive: drive the error occurred on
595 * @msg: message to report
597 * ide_abort kills and cleans up when we are about to do a
598 * host initiated reset on active commands. Longer term we
599 * want handlers to have sensible abort handling themselves
601 * This differs fundamentally from ide_error because in
602 * this case the command is doing just fine when we
606 ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
610 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
613 /* retry only "normal" I/O: */
614 if (!blk_fs_request(rq)) {
616 ide_end_drive_cmd(drive, BUSY_STAT, 0);
623 drv = *(ide_driver_t **)rq->rq_disk->private_data;
624 return drv->abort(drive, rq);
626 return __ide_abort(drive, rq);
630 * drive_cmd_intr - drive command completion interrupt
631 * @drive: drive the completion interrupt occurred on
633 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
634 * We do any necessary data reading and then wait for the drive to
635 * go non busy. At that point we may read the error data and complete
639 static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
641 struct request *rq = HWGROUP(drive)->rq;
642 ide_hwif_t *hwif = HWIF(drive);
643 u8 *args = (u8 *) rq->buffer;
644 u8 stat = hwif->INB(IDE_STATUS_REG);
647 local_irq_enable_in_hardirq();
648 if (rq->cmd_type == REQ_TYPE_ATA_CMD &&
649 (stat & DRQ_STAT) && args && args[3]) {
650 u8 io_32bit = drive->io_32bit;
652 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
653 drive->io_32bit = io_32bit;
654 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
658 if (!OK_STAT(stat, READY_STAT, BAD_STAT))
659 return ide_error(drive, "drive_cmd", stat);
660 /* calls ide_end_drive_cmd */
661 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
665 static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
667 tf->nsect = drive->sect;
668 tf->lbal = drive->sect;
669 tf->lbam = drive->cyl;
670 tf->lbah = drive->cyl >> 8;
671 tf->device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA;
672 tf->command = WIN_SPECIFY;
675 static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
677 tf->nsect = drive->sect;
678 tf->command = WIN_RESTORE;
681 static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf)
683 tf->nsect = drive->mult_req;
684 tf->command = WIN_SETMULT;
687 static ide_startstop_t ide_disk_special(ide_drive_t *drive)
689 special_t *s = &drive->special;
692 memset(&args, 0, sizeof(ide_task_t));
693 args.data_phase = TASKFILE_NO_DATA;
695 if (s->b.set_geometry) {
696 s->b.set_geometry = 0;
697 ide_tf_set_specify_cmd(drive, &args.tf);
698 } else if (s->b.recalibrate) {
699 s->b.recalibrate = 0;
700 ide_tf_set_restore_cmd(drive, &args.tf);
701 } else if (s->b.set_multmode) {
702 s->b.set_multmode = 0;
703 if (drive->mult_req > drive->id->max_multsect)
704 drive->mult_req = drive->id->max_multsect;
705 ide_tf_set_setmult_cmd(drive, &args.tf);
707 int special = s->all;
709 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
713 args.tf_flags = IDE_TFLAG_OUT_TF | IDE_TFLAG_OUT_DEVICE |
714 IDE_TFLAG_CUSTOM_HANDLER;
716 do_rw_taskfile(drive, &args);
722 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away
724 static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio)
733 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0;
736 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0;
739 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0;
746 * do_special - issue some special commands
747 * @drive: drive the command is for
749 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
750 * commands to a drive. It used to do much more, but has been scaled
754 static ide_startstop_t do_special (ide_drive_t *drive)
756 special_t *s = &drive->special;
759 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
762 ide_hwif_t *hwif = drive->hwif;
763 u8 req_pio = drive->tune_req;
767 if (set_pio_mode_abuse(drive->hwif, req_pio)) {
769 if (hwif->set_pio_mode == NULL)
773 * take ide_lock for drive->[no_]unmask/[no_]io_32bit
775 if (req_pio == 8 || req_pio == 9) {
778 spin_lock_irqsave(&ide_lock, flags);
779 hwif->set_pio_mode(drive, req_pio);
780 spin_unlock_irqrestore(&ide_lock, flags);
782 hwif->set_pio_mode(drive, req_pio);
784 int keep_dma = drive->using_dma;
786 ide_set_pio(drive, req_pio);
788 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) {
796 if (drive->media == ide_disk)
797 return ide_disk_special(drive);
805 void ide_map_sg(ide_drive_t *drive, struct request *rq)
807 ide_hwif_t *hwif = drive->hwif;
808 struct scatterlist *sg = hwif->sg_table;
810 if (hwif->sg_mapped) /* needed by ide-scsi */
813 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) {
814 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
816 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
821 EXPORT_SYMBOL_GPL(ide_map_sg);
823 void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
825 ide_hwif_t *hwif = drive->hwif;
827 hwif->nsect = hwif->nleft = rq->nr_sectors;
832 EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
835 * execute_drive_command - issue special drive command
836 * @drive: the drive to issue the command on
837 * @rq: the request structure holding the command
839 * execute_drive_cmd() issues a special drive command, usually
840 * initiated by ioctl() from the external hdparm program. The
841 * command can be a drive command, drive task or taskfile
842 * operation. Weirdly you can call it with NULL to wait for
843 * all commands to finish. Don't do this as that is due to change
846 static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
849 ide_hwif_t *hwif = HWIF(drive);
850 u8 *args = rq->buffer;
852 struct ide_taskfile *tf = <ask.tf;
854 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) {
855 ide_task_t *task = rq->special;
860 hwif->data_phase = task->data_phase;
862 switch (hwif->data_phase) {
863 case TASKFILE_MULTI_OUT:
865 case TASKFILE_MULTI_IN:
867 ide_init_sg_cmd(drive, rq);
868 ide_map_sg(drive, rq);
873 return do_rw_taskfile(drive, task);
879 memset(<ask, 0, sizeof(ltask));
880 if (rq->cmd_type == REQ_TYPE_ATA_CMD) {
882 printk("%s: DRIVE_CMD\n", drive->name);
884 tf->feature = args[2];
885 if (args[0] == WIN_SMART) {
890 ltask.tf_flags = IDE_TFLAG_OUT_TF;
893 ltask.tf_flags = IDE_TFLAG_OUT_FEATURE |
897 tf->command = args[0];
898 ide_tf_load(drive, <ask);
899 ide_execute_command(drive, args[0], &drive_cmd_intr, WAIT_WORSTCASE, NULL);
904 * NULL is actually a valid way of waiting for
905 * all current requests to be flushed from the queue.
908 printk("%s: DRIVE_CMD (null)\n", drive->name);
910 ide_end_drive_cmd(drive,
911 hwif->INB(IDE_STATUS_REG),
912 hwif->INB(IDE_ERROR_REG));
916 static void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
918 struct request_pm_state *pm = rq->data;
920 if (blk_pm_suspend_request(rq) &&
921 pm->pm_step == ide_pm_state_start_suspend)
922 /* Mark drive blocked when starting the suspend sequence. */
924 else if (blk_pm_resume_request(rq) &&
925 pm->pm_step == ide_pm_state_start_resume) {
927 * The first thing we do on wakeup is to wait for BSY bit to
928 * go away (with a looong timeout) as a drive on this hwif may
929 * just be POSTing itself.
930 * We do that before even selecting as the "other" device on
931 * the bus may be broken enough to walk on our toes at this
936 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
938 rc = ide_wait_not_busy(HWIF(drive), 35000);
940 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
942 ide_set_irq(drive, 1);
943 rc = ide_wait_not_busy(HWIF(drive), 100000);
945 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
950 * start_request - start of I/O and command issuing for IDE
952 * start_request() initiates handling of a new I/O request. It
953 * accepts commands and I/O (read/write) requests. It also does
954 * the final remapping for weird stuff like EZDrive. Once
955 * device mapper can work sector level the EZDrive stuff can go away
957 * FIXME: this function needs a rename
960 static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
962 ide_startstop_t startstop;
965 BUG_ON(!blk_rq_started(rq));
968 printk("%s: start_request: current=0x%08lx\n",
969 HWIF(drive)->name, (unsigned long) rq);
972 /* bail early if we've exceeded max_failures */
973 if (drive->max_failures && (drive->failures > drive->max_failures)) {
974 rq->cmd_flags |= REQ_FAILED;
979 if (blk_fs_request(rq) &&
980 (drive->media == ide_disk || drive->media == ide_floppy)) {
981 block += drive->sect0;
983 /* Yecch - this will shift the entire interval,
984 possibly killing some innocent following sector */
985 if (block == 0 && drive->remap_0_to_1 == 1)
986 block = 1; /* redirect MBR access to EZ-Drive partn table */
988 if (blk_pm_request(rq))
989 ide_check_pm_state(drive, rq);
992 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
993 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
996 if (!drive->special.all) {
1000 * We reset the drive so we need to issue a SETFEATURES.
1001 * Do it _after_ do_special() restored device parameters.
1003 if (drive->current_speed == 0xff)
1004 ide_config_drive_speed(drive, drive->desired_speed);
1006 if (rq->cmd_type == REQ_TYPE_ATA_CMD ||
1007 rq->cmd_type == REQ_TYPE_ATA_TASKFILE)
1008 return execute_drive_cmd(drive, rq);
1009 else if (blk_pm_request(rq)) {
1010 struct request_pm_state *pm = rq->data;
1012 printk("%s: start_power_step(step: %d)\n",
1013 drive->name, rq->pm->pm_step);
1015 startstop = ide_start_power_step(drive, rq);
1016 if (startstop == ide_stopped &&
1017 pm->pm_step == ide_pm_state_completed)
1018 ide_complete_pm_request(drive, rq);
1022 drv = *(ide_driver_t **)rq->rq_disk->private_data;
1023 return drv->do_request(drive, rq, block);
1025 return do_special(drive);
1027 ide_kill_rq(drive, rq);
1032 * ide_stall_queue - pause an IDE device
1033 * @drive: drive to stall
1034 * @timeout: time to stall for (jiffies)
1036 * ide_stall_queue() can be used by a drive to give excess bandwidth back
1037 * to the hwgroup by sleeping for timeout jiffies.
1040 void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
1042 if (timeout > WAIT_WORSTCASE)
1043 timeout = WAIT_WORSTCASE;
1044 drive->sleep = timeout + jiffies;
1045 drive->sleeping = 1;
1048 EXPORT_SYMBOL(ide_stall_queue);
1050 #define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
1053 * choose_drive - select a drive to service
1054 * @hwgroup: hardware group to select on
1056 * choose_drive() selects the next drive which will be serviced.
1057 * This is necessary because the IDE layer can't issue commands
1058 * to both drives on the same cable, unlike SCSI.
1061 static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
1063 ide_drive_t *drive, *best;
1067 drive = hwgroup->drive;
1070 * drive is doing pre-flush, ordered write, post-flush sequence. even
1071 * though that is 3 requests, it must be seen as a single transaction.
1072 * we must not preempt this drive until that is complete
1074 if (blk_queue_flushing(drive->queue)) {
1076 * small race where queue could get replugged during
1077 * the 3-request flush cycle, just yank the plug since
1078 * we want it to finish asap
1080 blk_remove_plug(drive->queue);
1085 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep))
1086 && !elv_queue_empty(drive->queue)) {
1088 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep)))
1089 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best))))
1091 if (!blk_queue_plugged(drive->queue))
1095 } while ((drive = drive->next) != hwgroup->drive);
1096 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1097 long t = (signed long)(WAKEUP(best) - jiffies);
1098 if (t >= WAIT_MIN_SLEEP) {
1100 * We *may* have some time to spare, but first let's see if
1101 * someone can potentially benefit from our nice mood today..
1105 if (!drive->sleeping
1106 && time_before(jiffies - best->service_time, WAKEUP(drive))
1107 && time_before(WAKEUP(drive), jiffies + t))
1109 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1112 } while ((drive = drive->next) != best);
1119 * Issue a new request to a drive from hwgroup
1120 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1122 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1123 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1124 * may have both interfaces in a single hwgroup to "serialize" access.
1125 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1126 * together into one hwgroup for serialized access.
1128 * Note also that several hwgroups can end up sharing a single IRQ,
1129 * possibly along with many other devices. This is especially common in
1130 * PCI-based systems with off-board IDE controller cards.
1132 * The IDE driver uses the single global ide_lock spinlock to protect
1133 * access to the request queues, and to protect the hwgroup->busy flag.
1135 * The first thread into the driver for a particular hwgroup sets the
1136 * hwgroup->busy flag to indicate that this hwgroup is now active,
1137 * and then initiates processing of the top request from the request queue.
1139 * Other threads attempting entry notice the busy setting, and will simply
1140 * queue their new requests and exit immediately. Note that hwgroup->busy
1141 * remains set even when the driver is merely awaiting the next interrupt.
1142 * Thus, the meaning is "this hwgroup is busy processing a request".
1144 * When processing of a request completes, the completing thread or IRQ-handler
1145 * will start the next request from the queue. If no more work remains,
1146 * the driver will clear the hwgroup->busy flag and exit.
1148 * The ide_lock (spinlock) is used to protect all access to the
1149 * hwgroup->busy flag, but is otherwise not needed for most processing in
1150 * the driver. This makes the driver much more friendlier to shared IRQs
1151 * than previous designs, while remaining 100% (?) SMP safe and capable.
1153 static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1158 ide_startstop_t startstop;
1161 /* for atari only: POSSIBLY BROKEN HERE(?) */
1162 ide_get_lock(ide_intr, hwgroup);
1164 /* caller must own ide_lock */
1165 BUG_ON(!irqs_disabled());
1167 while (!hwgroup->busy) {
1169 drive = choose_drive(hwgroup);
1170 if (drive == NULL) {
1172 unsigned long sleep = 0; /* shut up, gcc */
1174 drive = hwgroup->drive;
1176 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) {
1178 sleep = drive->sleep;
1180 } while ((drive = drive->next) != hwgroup->drive);
1183 * Take a short snooze, and then wake up this hwgroup again.
1184 * This gives other hwgroups on the same a chance to
1185 * play fairly with us, just in case there are big differences
1186 * in relative throughputs.. don't want to hog the cpu too much.
1188 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1189 sleep = jiffies + WAIT_MIN_SLEEP;
1191 if (timer_pending(&hwgroup->timer))
1192 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1194 /* so that ide_timer_expiry knows what to do */
1195 hwgroup->sleeping = 1;
1196 hwgroup->req_gen_timer = hwgroup->req_gen;
1197 mod_timer(&hwgroup->timer, sleep);
1198 /* we purposely leave hwgroup->busy==1
1201 /* Ugly, but how can we sleep for the lock
1202 * otherwise? perhaps from tq_disk?
1205 /* for atari only */
1210 /* no more work for this hwgroup (for now) */
1215 if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) {
1217 * set nIEN for previous hwif, drives in the
1218 * quirk_list may not like intr setups/cleanups
1220 if (drive->quirk_list != 1)
1221 ide_set_irq(drive, 0);
1223 hwgroup->hwif = hwif;
1224 hwgroup->drive = drive;
1225 drive->sleeping = 0;
1226 drive->service_start = jiffies;
1228 if (blk_queue_plugged(drive->queue)) {
1229 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1234 * we know that the queue isn't empty, but this can happen
1235 * if the q->prep_rq_fn() decides to kill a request
1237 rq = elv_next_request(drive->queue);
1244 * Sanity: don't accept a request that isn't a PM request
1245 * if we are currently power managed. This is very important as
1246 * blk_stop_queue() doesn't prevent the elv_next_request()
1247 * above to return us whatever is in the queue. Since we call
1248 * ide_do_request() ourselves, we end up taking requests while
1249 * the queue is blocked...
1251 * We let requests forced at head of queue with ide-preempt
1252 * though. I hope that doesn't happen too much, hopefully not
1253 * unless the subdriver triggers such a thing in its own PM
1256 * We count how many times we loop here to make sure we service
1257 * all drives in the hwgroup without looping for ever
1259 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) {
1260 drive = drive->next ? drive->next : hwgroup->drive;
1261 if (loops++ < 4 && !blk_queue_plugged(drive->queue))
1263 /* We clear busy, there should be no pending ATA command at this point. */
1271 * Some systems have trouble with IDE IRQs arriving while
1272 * the driver is still setting things up. So, here we disable
1273 * the IRQ used by this interface while the request is being started.
1274 * This may look bad at first, but pretty much the same thing
1275 * happens anyway when any interrupt comes in, IDE or otherwise
1276 * -- the kernel masks the IRQ while it is being handled.
1278 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1279 disable_irq_nosync(hwif->irq);
1280 spin_unlock(&ide_lock);
1281 local_irq_enable_in_hardirq();
1282 /* allow other IRQs while we start this request */
1283 startstop = start_request(drive, rq);
1284 spin_lock_irq(&ide_lock);
1285 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq)
1286 enable_irq(hwif->irq);
1287 if (startstop == ide_stopped)
1293 * Passes the stuff to ide_do_request
1295 void do_ide_request(struct request_queue *q)
1297 ide_drive_t *drive = q->queuedata;
1299 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1303 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1304 * retry the current request in pio mode instead of risking tossing it
1307 static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1309 ide_hwif_t *hwif = HWIF(drive);
1311 ide_startstop_t ret = ide_stopped;
1314 * end current dma transaction
1318 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1319 (void)HWIF(drive)->ide_dma_end(drive);
1320 ret = ide_error(drive, "dma timeout error",
1321 hwif->INB(IDE_STATUS_REG));
1323 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
1324 hwif->dma_timeout(drive);
1328 * disable dma for now, but remember that we did so because of
1329 * a timeout -- we'll reenable after we finish this next request
1330 * (or rather the first chunk of it) in pio.
1333 drive->state = DMA_PIO_RETRY;
1334 ide_dma_off_quietly(drive);
1337 * un-busy drive etc (hwgroup->busy is cleared on return) and
1338 * make sure request is sane
1340 rq = HWGROUP(drive)->rq;
1345 HWGROUP(drive)->rq = NULL;
1352 rq->sector = rq->bio->bi_sector;
1353 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1354 rq->hard_cur_sectors = rq->current_nr_sectors;
1355 rq->buffer = bio_data(rq->bio);
1361 * ide_timer_expiry - handle lack of an IDE interrupt
1362 * @data: timer callback magic (hwgroup)
1364 * An IDE command has timed out before the expected drive return
1365 * occurred. At this point we attempt to clean up the current
1366 * mess. If the current handler includes an expiry handler then
1367 * we invoke the expiry handler, and providing it is happy the
1368 * work is done. If that fails we apply generic recovery rules
1369 * invoking the handler and checking the drive DMA status. We
1370 * have an excessively incestuous relationship with the DMA
1371 * logic that wants cleaning up.
1374 void ide_timer_expiry (unsigned long data)
1376 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1377 ide_handler_t *handler;
1378 ide_expiry_t *expiry;
1379 unsigned long flags;
1380 unsigned long wait = -1;
1382 spin_lock_irqsave(&ide_lock, flags);
1384 if (((handler = hwgroup->handler) == NULL) ||
1385 (hwgroup->req_gen != hwgroup->req_gen_timer)) {
1387 * Either a marginal timeout occurred
1388 * (got the interrupt just as timer expired),
1389 * or we were "sleeping" to give other devices a chance.
1390 * Either way, we don't really want to complain about anything.
1392 if (hwgroup->sleeping) {
1393 hwgroup->sleeping = 0;
1397 ide_drive_t *drive = hwgroup->drive;
1399 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1400 hwgroup->handler = NULL;
1403 ide_startstop_t startstop = ide_stopped;
1404 if (!hwgroup->busy) {
1405 hwgroup->busy = 1; /* paranoia */
1406 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1408 if ((expiry = hwgroup->expiry) != NULL) {
1410 if ((wait = expiry(drive)) > 0) {
1412 hwgroup->timer.expires = jiffies + wait;
1413 hwgroup->req_gen_timer = hwgroup->req_gen;
1414 add_timer(&hwgroup->timer);
1415 spin_unlock_irqrestore(&ide_lock, flags);
1419 hwgroup->handler = NULL;
1421 * We need to simulate a real interrupt when invoking
1422 * the handler() function, which means we need to
1423 * globally mask the specific IRQ:
1425 spin_unlock(&ide_lock);
1427 /* disable_irq_nosync ?? */
1428 disable_irq(hwif->irq);
1430 * as if we were handling an interrupt */
1431 local_irq_disable();
1432 if (hwgroup->polling) {
1433 startstop = handler(drive);
1434 } else if (drive_is_ready(drive)) {
1435 if (drive->waiting_for_dma)
1436 hwgroup->hwif->dma_lost_irq(drive);
1437 (void)ide_ack_intr(hwif);
1438 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1439 startstop = handler(drive);
1441 if (drive->waiting_for_dma) {
1442 startstop = ide_dma_timeout_retry(drive, wait);
1445 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG));
1447 drive->service_time = jiffies - drive->service_start;
1448 spin_lock_irq(&ide_lock);
1449 enable_irq(hwif->irq);
1450 if (startstop == ide_stopped)
1454 ide_do_request(hwgroup, IDE_NO_IRQ);
1455 spin_unlock_irqrestore(&ide_lock, flags);
1459 * unexpected_intr - handle an unexpected IDE interrupt
1460 * @irq: interrupt line
1461 * @hwgroup: hwgroup being processed
1463 * There's nothing really useful we can do with an unexpected interrupt,
1464 * other than reading the status register (to clear it), and logging it.
1465 * There should be no way that an irq can happen before we're ready for it,
1466 * so we needn't worry much about losing an "important" interrupt here.
1468 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1469 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1470 * looks "good", we just ignore the interrupt completely.
1472 * This routine assumes __cli() is in effect when called.
1474 * If an unexpected interrupt happens on irq15 while we are handling irq14
1475 * and if the two interfaces are "serialized" (CMD640), then it looks like
1476 * we could screw up by interfering with a new request being set up for
1479 * In reality, this is a non-issue. The new command is not sent unless
1480 * the drive is ready to accept one, in which case we know the drive is
1481 * not trying to interrupt us. And ide_set_handler() is always invoked
1482 * before completing the issuance of any new drive command, so we will not
1483 * be accidentally invoked as a result of any valid command completion
1486 * Note that we must walk the entire hwgroup here. We know which hwif
1487 * is doing the current command, but we don't know which hwif burped
1491 static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1494 ide_hwif_t *hwif = hwgroup->hwif;
1497 * handle the unexpected interrupt
1500 if (hwif->irq == irq) {
1501 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1502 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1503 /* Try to not flood the console with msgs */
1504 static unsigned long last_msgtime, count;
1506 if (time_after(jiffies, last_msgtime + HZ)) {
1507 last_msgtime = jiffies;
1508 printk(KERN_ERR "%s%s: unexpected interrupt, "
1509 "status=0x%02x, count=%ld\n",
1511 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1515 } while ((hwif = hwif->next) != hwgroup->hwif);
1519 * ide_intr - default IDE interrupt handler
1520 * @irq: interrupt number
1521 * @dev_id: hwif group
1522 * @regs: unused weirdness from the kernel irq layer
1524 * This is the default IRQ handler for the IDE layer. You should
1525 * not need to override it. If you do be aware it is subtle in
1528 * hwgroup->hwif is the interface in the group currently performing
1529 * a command. hwgroup->drive is the drive and hwgroup->handler is
1530 * the IRQ handler to call. As we issue a command the handlers
1531 * step through multiple states, reassigning the handler to the
1532 * next step in the process. Unlike a smart SCSI controller IDE
1533 * expects the main processor to sequence the various transfer
1534 * stages. We also manage a poll timer to catch up with most
1535 * timeout situations. There are still a few where the handlers
1536 * don't ever decide to give up.
1538 * The handler eventually returns ide_stopped to indicate the
1539 * request completed. At this point we issue the next request
1540 * on the hwgroup and the process begins again.
1543 irqreturn_t ide_intr (int irq, void *dev_id)
1545 unsigned long flags;
1546 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1549 ide_handler_t *handler;
1550 ide_startstop_t startstop;
1552 spin_lock_irqsave(&ide_lock, flags);
1553 hwif = hwgroup->hwif;
1555 if (!ide_ack_intr(hwif)) {
1556 spin_unlock_irqrestore(&ide_lock, flags);
1560 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) {
1562 * Not expecting an interrupt from this drive.
1563 * That means this could be:
1564 * (1) an interrupt from another PCI device
1565 * sharing the same PCI INT# as us.
1566 * or (2) a drive just entered sleep or standby mode,
1567 * and is interrupting to let us know.
1568 * or (3) a spurious interrupt of unknown origin.
1570 * For PCI, we cannot tell the difference,
1571 * so in that case we just ignore it and hope it goes away.
1573 * FIXME: unexpected_intr should be hwif-> then we can
1574 * remove all the ifdef PCI crap
1576 #ifdef CONFIG_BLK_DEV_IDEPCI
1577 if (hwif->pci_dev && !hwif->pci_dev->vendor)
1578 #endif /* CONFIG_BLK_DEV_IDEPCI */
1581 * Probably not a shared PCI interrupt,
1582 * so we can safely try to do something about it:
1584 unexpected_intr(irq, hwgroup);
1585 #ifdef CONFIG_BLK_DEV_IDEPCI
1588 * Whack the status register, just in case
1589 * we have a leftover pending IRQ.
1591 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1592 #endif /* CONFIG_BLK_DEV_IDEPCI */
1594 spin_unlock_irqrestore(&ide_lock, flags);
1597 drive = hwgroup->drive;
1600 * This should NEVER happen, and there isn't much
1601 * we could do about it here.
1603 * [Note - this can occur if the drive is hot unplugged]
1605 spin_unlock_irqrestore(&ide_lock, flags);
1608 if (!drive_is_ready(drive)) {
1610 * This happens regularly when we share a PCI IRQ with
1611 * another device. Unfortunately, it can also happen
1612 * with some buggy drives that trigger the IRQ before
1613 * their status register is up to date. Hopefully we have
1614 * enough advance overhead that the latter isn't a problem.
1616 spin_unlock_irqrestore(&ide_lock, flags);
1619 if (!hwgroup->busy) {
1620 hwgroup->busy = 1; /* paranoia */
1621 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1623 hwgroup->handler = NULL;
1625 del_timer(&hwgroup->timer);
1626 spin_unlock(&ide_lock);
1628 /* Some controllers might set DMA INTR no matter DMA or PIO;
1629 * bmdma status might need to be cleared even for
1630 * PIO interrupts to prevent spurious/lost irq.
1632 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma))
1633 /* ide_dma_end() needs bmdma status for error checking.
1634 * So, skip clearing bmdma status here and leave it
1635 * to ide_dma_end() if this is dma interrupt.
1637 hwif->ide_dma_clear_irq(drive);
1640 local_irq_enable_in_hardirq();
1641 /* service this interrupt, may set handler for next interrupt */
1642 startstop = handler(drive);
1643 spin_lock_irq(&ide_lock);
1646 * Note that handler() may have set things up for another
1647 * interrupt to occur soon, but it cannot happen until
1648 * we exit from this routine, because it will be the
1649 * same irq as is currently being serviced here, and Linux
1650 * won't allow another of the same (on any CPU) until we return.
1652 drive->service_time = jiffies - drive->service_start;
1653 if (startstop == ide_stopped) {
1654 if (hwgroup->handler == NULL) { /* paranoia */
1656 ide_do_request(hwgroup, hwif->irq);
1658 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1659 "on exit\n", drive->name);
1662 spin_unlock_irqrestore(&ide_lock, flags);
1667 * ide_init_drive_cmd - initialize a drive command request
1668 * @rq: request object
1670 * Initialize a request before we fill it in and send it down to
1671 * ide_do_drive_cmd. Commands must be set up by this function. Right
1672 * now it doesn't do a lot, but if that changes abusers will have a
1676 void ide_init_drive_cmd (struct request *rq)
1678 memset(rq, 0, sizeof(*rq));
1679 rq->cmd_type = REQ_TYPE_ATA_CMD;
1683 EXPORT_SYMBOL(ide_init_drive_cmd);
1686 * ide_do_drive_cmd - issue IDE special command
1687 * @drive: device to issue command
1688 * @rq: request to issue
1689 * @action: action for processing
1691 * This function issues a special IDE device request
1692 * onto the request queue.
1694 * If action is ide_wait, then the rq is queued at the end of the
1695 * request queue, and the function sleeps until it has been processed.
1696 * This is for use when invoked from an ioctl handler.
1698 * If action is ide_preempt, then the rq is queued at the head of
1699 * the request queue, displacing the currently-being-processed
1700 * request and this function returns immediately without waiting
1701 * for the new rq to be completed. This is VERY DANGEROUS, and is
1702 * intended for careful use by the ATAPI tape/cdrom driver code.
1704 * If action is ide_end, then the rq is queued at the end of the
1705 * request queue, and the function returns immediately without waiting
1706 * for the new rq to be completed. This is again intended for careful
1707 * use by the ATAPI tape/cdrom driver code.
1710 int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1712 unsigned long flags;
1713 ide_hwgroup_t *hwgroup = HWGROUP(drive);
1714 DECLARE_COMPLETION_ONSTACK(wait);
1715 int where = ELEVATOR_INSERT_BACK, err;
1716 int must_wait = (action == ide_wait || action == ide_head_wait);
1721 * we need to hold an extra reference to request for safe inspection
1726 rq->end_io_data = &wait;
1727 rq->end_io = blk_end_sync_rq;
1730 spin_lock_irqsave(&ide_lock, flags);
1731 if (action == ide_preempt)
1733 if (action == ide_preempt || action == ide_head_wait) {
1734 where = ELEVATOR_INSERT_FRONT;
1735 rq->cmd_flags |= REQ_PREEMPT;
1737 __elv_add_request(drive->queue, rq, where, 0);
1738 ide_do_request(hwgroup, IDE_NO_IRQ);
1739 spin_unlock_irqrestore(&ide_lock, flags);
1743 wait_for_completion(&wait);
1747 blk_put_request(rq);
1753 EXPORT_SYMBOL(ide_do_drive_cmd);
1755 void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma)
1759 memset(&task, 0, sizeof(task));
1760 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM |
1761 IDE_TFLAG_OUT_FEATURE | tf_flags;
1762 task.tf.feature = dma; /* Use PIO/DMA */
1763 task.tf.lbam = bcount & 0xff;
1764 task.tf.lbah = (bcount >> 8) & 0xff;
1766 ide_tf_load(drive, &task);
1769 EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load);