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/config.h>
28 #include <linux/module.h>
29 #include <linux/types.h>
30 #include <linux/string.h>
31 #include <linux/kernel.h>
32 #include <linux/timer.h>
34 #include <linux/interrupt.h>
35 #include <linux/major.h>
36 #include <linux/errno.h>
37 #include <linux/genhd.h>
38 #include <linux/blkpg.h>
39 #include <linux/slab.h>
40 #include <linux/init.h>
41 #include <linux/pci.h>
42 #include <linux/delay.h>
43 #include <linux/ide.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>
52 #include <asm/byteorder.h>
54 #include <asm/uaccess.h>
56 #include <asm/bitops.h>
58 static void ide_fill_flush_cmd(ide_drive_t *drive, struct request *rq)
63 * reuse cdb space for ata command
65 memset(buf, 0, sizeof(rq->cmd));
67 rq->flags |= REQ_DRIVE_TASK | REQ_STARTED;
69 rq->buffer[0] = WIN_FLUSH_CACHE;
71 if (ide_id_has_flush_cache_ext(drive->id) &&
72 (drive->capacity64 >= (1UL << 28)))
73 rq->buffer[0] = WIN_FLUSH_CACHE_EXT;
77 * preempt pending requests, and store this cache flush for immediate
80 static struct request *ide_queue_flush_cmd(ide_drive_t *drive,
81 struct request *rq, int post)
83 struct request *flush_rq = &HWGROUP(drive)->wrq;
86 * write cache disabled, clear the barrier bit and treat it like
90 rq->flags |= REQ_BAR_PREFLUSH;
94 ide_init_drive_cmd(flush_rq);
95 ide_fill_flush_cmd(drive, flush_rq);
97 flush_rq->special = rq;
98 flush_rq->nr_sectors = rq->nr_sectors;
101 drive->doing_barrier = 1;
102 flush_rq->flags |= REQ_BAR_PREFLUSH;
103 blkdev_dequeue_request(rq);
105 flush_rq->flags |= REQ_BAR_POSTFLUSH;
107 __elv_add_request(drive->queue, flush_rq, ELEVATOR_INSERT_FRONT, 0);
108 HWGROUP(drive)->rq = NULL;
112 static int __ide_end_request(ide_drive_t *drive, struct request *rq,
113 int uptodate, int nr_sectors)
117 BUG_ON(!(rq->flags & REQ_STARTED));
120 * if failfast is set on a request, override number of sectors and
121 * complete the whole request right now
123 if (blk_noretry_request(rq) && end_io_error(uptodate))
124 nr_sectors = rq->hard_nr_sectors;
126 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
130 * decide whether to reenable DMA -- 3 is a random magic for now,
131 * if we DMA timeout more than 3 times, just stay in PIO
133 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
135 HWGROUP(drive)->hwif->ide_dma_on(drive);
138 if (!end_that_request_first(rq, uptodate, nr_sectors)) {
139 add_disk_randomness(rq->rq_disk);
141 if (blk_rq_tagged(rq))
142 blk_queue_end_tag(drive->queue, rq);
144 blkdev_dequeue_request(rq);
145 HWGROUP(drive)->rq = NULL;
146 end_that_request_last(rq);
153 * ide_end_request - complete an IDE I/O
154 * @drive: IDE device for the I/O
156 * @nr_sectors: number of sectors completed
158 * This is our end_request wrapper function. We complete the I/O
159 * update random number input and dequeue the request, which if
160 * it was tagged may be out of order.
163 int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
169 spin_lock_irqsave(&ide_lock, flags);
170 rq = HWGROUP(drive)->rq;
173 nr_sectors = rq->hard_cur_sectors;
175 if (!blk_barrier_rq(rq) || !drive->wcache)
176 ret = __ide_end_request(drive, rq, uptodate, nr_sectors);
178 struct request *flush_rq = &HWGROUP(drive)->wrq;
180 flush_rq->nr_sectors -= nr_sectors;
181 if (!flush_rq->nr_sectors) {
182 ide_queue_flush_cmd(drive, rq, 1);
187 spin_unlock_irqrestore(&ide_lock, flags);
190 EXPORT_SYMBOL(ide_end_request);
193 * ide_end_dequeued_request - complete an IDE I/O
194 * @drive: IDE device for the I/O
196 * @nr_sectors: number of sectors completed
198 * Complete an I/O that is no longer on the request queue. This
199 * typically occurs when we pull the request and issue a REQUEST_SENSE.
200 * We must still finish the old request but we must not tamper with the
201 * queue in the meantime.
203 * NOTE: This path does not handle barrier, but barrier is not supported
207 int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq,
208 int uptodate, int nr_sectors)
213 spin_lock_irqsave(&ide_lock, flags);
215 BUG_ON(!(rq->flags & REQ_STARTED));
218 * if failfast is set on a request, override number of sectors and
219 * complete the whole request right now
221 if (blk_noretry_request(rq) && end_io_error(uptodate))
222 nr_sectors = rq->hard_nr_sectors;
224 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors)
228 * decide whether to reenable DMA -- 3 is a random magic for now,
229 * if we DMA timeout more than 3 times, just stay in PIO
231 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) {
233 HWGROUP(drive)->hwif->ide_dma_on(drive);
236 if (!end_that_request_first(rq, uptodate, nr_sectors)) {
237 add_disk_randomness(rq->rq_disk);
238 if (blk_rq_tagged(rq))
239 blk_queue_end_tag(drive->queue, rq);
240 end_that_request_last(rq);
243 spin_unlock_irqrestore(&ide_lock, flags);
246 EXPORT_SYMBOL_GPL(ide_end_dequeued_request);
249 * ide_complete_pm_request - end the current Power Management request
250 * @drive: target drive
253 * This function cleans up the current PM request and stops the queue
256 static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
261 printk("%s: completing PM request, %s\n", drive->name,
262 blk_pm_suspend_request(rq) ? "suspend" : "resume");
264 spin_lock_irqsave(&ide_lock, flags);
265 if (blk_pm_suspend_request(rq)) {
266 blk_stop_queue(drive->queue);
269 blk_start_queue(drive->queue);
271 blkdev_dequeue_request(rq);
272 HWGROUP(drive)->rq = NULL;
273 end_that_request_last(rq);
274 spin_unlock_irqrestore(&ide_lock, flags);
278 * FIXME: probably move this somewhere else, name is bad too :)
280 u64 ide_get_error_location(ide_drive_t *drive, char *args)
291 if (ide_id_has_flush_cache_ext(drive->id)) {
292 low = (hcyl << 16) | (lcyl << 8) | sect;
293 HWIF(drive)->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
294 high = ide_read_24(drive);
296 u8 cur = HWIF(drive)->INB(IDE_SELECT_REG);
298 low = (hcyl << 16) | (lcyl << 8) | sect;
300 low = hcyl * drive->head * drive->sect;
301 low += lcyl * drive->sect;
306 sector = ((u64) high << 24) | low;
309 EXPORT_SYMBOL(ide_get_error_location);
311 static void ide_complete_barrier(ide_drive_t *drive, struct request *rq,
314 struct request *real_rq = rq->special;
315 int good_sectors, bad_sectors;
319 if (blk_barrier_postflush(rq)) {
321 * this completes the barrier write
323 __ide_end_request(drive, real_rq, 1, real_rq->hard_nr_sectors);
324 drive->doing_barrier = 0;
327 * just indicate that we did the pre flush
329 real_rq->flags |= REQ_BAR_PREFLUSH;
330 elv_requeue_request(drive->queue, real_rq);
333 * all is fine, return
339 * we need to end real_rq, but it's not on the queue currently.
340 * put it back on the queue, so we don't have to special case
341 * anything else for completing it
343 if (!blk_barrier_postflush(rq))
344 elv_requeue_request(drive->queue, real_rq);
347 * drive aborted flush command, assume FLUSH_CACHE_* doesn't
348 * work and disable barrier support
350 if (error & ABRT_ERR) {
351 printk(KERN_ERR "%s: barrier support doesn't work\n", drive->name);
352 __ide_end_request(drive, real_rq, -EOPNOTSUPP, real_rq->hard_nr_sectors);
353 blk_queue_ordered(drive->queue, 0);
354 blk_queue_issue_flush_fn(drive->queue, NULL);
357 * find out what part of the request failed
360 if (blk_barrier_postflush(rq)) {
361 sector = ide_get_error_location(drive, rq->buffer);
363 if ((sector >= real_rq->hard_sector) &&
364 (sector < real_rq->hard_sector + real_rq->hard_nr_sectors))
365 good_sectors = sector - real_rq->hard_sector;
367 sector = real_rq->hard_sector;
369 bad_sectors = real_rq->hard_nr_sectors - good_sectors;
371 __ide_end_request(drive, real_rq, 1, good_sectors);
373 __ide_end_request(drive, real_rq, 0, bad_sectors);
375 printk(KERN_ERR "%s: failed barrier write: "
376 "sector=%Lx(good=%d/bad=%d)\n",
377 drive->name, (unsigned long long)sector,
378 good_sectors, bad_sectors);
381 drive->doing_barrier = 0;
385 * ide_end_drive_cmd - end an explicit drive command
390 * Clean up after success/failure of an explicit drive command.
391 * These get thrown onto the queue so they are synchronized with
392 * real I/O operations on the drive.
394 * In LBA48 mode we have to read the register set twice to get
395 * all the extra information out.
398 void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
400 ide_hwif_t *hwif = HWIF(drive);
404 spin_lock_irqsave(&ide_lock, flags);
405 rq = HWGROUP(drive)->rq;
406 spin_unlock_irqrestore(&ide_lock, flags);
408 if (rq->flags & REQ_DRIVE_CMD) {
409 u8 *args = (u8 *) rq->buffer;
411 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
416 args[2] = hwif->INB(IDE_NSECTOR_REG);
418 } else if (rq->flags & REQ_DRIVE_TASK) {
419 u8 *args = (u8 *) rq->buffer;
421 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
426 args[2] = hwif->INB(IDE_NSECTOR_REG);
427 args[3] = hwif->INB(IDE_SECTOR_REG);
428 args[4] = hwif->INB(IDE_LCYL_REG);
429 args[5] = hwif->INB(IDE_HCYL_REG);
430 args[6] = hwif->INB(IDE_SELECT_REG);
432 } else if (rq->flags & REQ_DRIVE_TASKFILE) {
433 ide_task_t *args = (ide_task_t *) rq->special;
435 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT);
438 if (args->tf_in_flags.b.data) {
439 u16 data = hwif->INW(IDE_DATA_REG);
440 args->tfRegister[IDE_DATA_OFFSET] = (data) & 0xFF;
441 args->hobRegister[IDE_DATA_OFFSET] = (data >> 8) & 0xFF;
443 args->tfRegister[IDE_ERROR_OFFSET] = err;
444 /* be sure we're looking at the low order bits */
445 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG);
446 args->tfRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
447 args->tfRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
448 args->tfRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
449 args->tfRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
450 args->tfRegister[IDE_SELECT_OFFSET] = hwif->INB(IDE_SELECT_REG);
451 args->tfRegister[IDE_STATUS_OFFSET] = stat;
453 if (drive->addressing == 1) {
454 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG);
455 args->hobRegister[IDE_FEATURE_OFFSET] = hwif->INB(IDE_FEATURE_REG);
456 args->hobRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG);
457 args->hobRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG);
458 args->hobRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG);
459 args->hobRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG);
462 } else if (blk_pm_request(rq)) {
464 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
465 drive->name, rq->pm->pm_step, stat, err);
467 DRIVER(drive)->complete_power_step(drive, rq, stat, err);
468 if (rq->pm->pm_step == ide_pm_state_completed)
469 ide_complete_pm_request(drive, rq);
473 spin_lock_irqsave(&ide_lock, flags);
474 blkdev_dequeue_request(rq);
476 if (blk_barrier_preflush(rq) || blk_barrier_postflush(rq))
477 ide_complete_barrier(drive, rq, err);
479 HWGROUP(drive)->rq = NULL;
480 end_that_request_last(rq);
481 spin_unlock_irqrestore(&ide_lock, flags);
484 EXPORT_SYMBOL(ide_end_drive_cmd);
487 * try_to_flush_leftover_data - flush junk
488 * @drive: drive to flush
490 * try_to_flush_leftover_data() is invoked in response to a drive
491 * unexpectedly having its DRQ_STAT bit set. As an alternative to
492 * resetting the drive, this routine tries to clear the condition
493 * by read a sector's worth of data from the drive. Of course,
494 * this may not help if the drive is *waiting* for data from *us*.
496 void try_to_flush_leftover_data (ide_drive_t *drive)
498 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS;
500 if (drive->media != ide_disk)
504 u32 wcount = (i > 16) ? 16 : i;
507 HWIF(drive)->ata_input_data(drive, buffer, wcount);
511 EXPORT_SYMBOL(try_to_flush_leftover_data);
514 * FIXME Add an ATAPI error
518 * ide_error - handle an error on the IDE
519 * @drive: drive the error occurred on
520 * @msg: message to report
523 * ide_error() takes action based on the error returned by the drive.
524 * For normal I/O that may well include retries. We deal with
525 * both new-style (taskfile) and old style command handling here.
526 * In the case of taskfile command handling there is work left to
530 ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
536 err = ide_dump_status(drive, msg, stat);
537 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL)
541 /* retry only "normal" I/O: */
542 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK)) {
544 ide_end_drive_cmd(drive, stat, err);
547 if (rq->flags & REQ_DRIVE_TASKFILE) {
549 ide_end_drive_cmd(drive, stat, err);
553 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) {
554 /* other bits are useless when BUSY */
555 rq->errors |= ERROR_RESET;
557 if (drive->media != ide_disk)
560 if (stat & ERR_STAT) {
561 /* err has different meaning on cdrom and tape */
562 if (err == ABRT_ERR) {
563 if (drive->select.b.lba &&
564 (hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY))
565 /* some newer drives don't
566 * support WIN_SPECIFY
569 } else if ((err & BAD_CRC) == BAD_CRC) {
571 /* UDMA crc error -- just retry the operation */
572 } else if (err & (BBD_ERR | ECC_ERR)) {
573 /* retries won't help these */
574 rq->errors = ERROR_MAX;
575 } else if (err & TRK0_ERR) {
576 /* help it find track zero */
577 rq->errors |= ERROR_RECAL;
581 if ((stat & DRQ_STAT) && rq_data_dir(rq) != WRITE)
582 try_to_flush_leftover_data(drive);
584 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) {
586 hwif->OUTB(WIN_IDLEIMMEDIATE,IDE_COMMAND_REG);
588 if (rq->errors >= ERROR_MAX) {
589 DRIVER(drive)->end_request(drive, 0, 0);
591 if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
593 return ide_do_reset(drive);
595 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL)
596 drive->special.b.recalibrate = 1;
603 * ide_abort - abort pending IDE operatins
604 * @drive: drive the error occurred on
605 * @msg: message to report
607 * ide_abort kills and cleans up when we are about to do a
608 * host initiated reset on active commands. Longer term we
609 * want handlers to have sensible abort handling themselves
611 * This differs fundamentally from ide_error because in
612 * this case the command is doing just fine when we
615 * FIXME: need to fix locking corner cases
618 ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
624 spin_lock_irqsave(&ide_lock, flags);
625 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) {
626 spin_unlock_irqrestore(&ide_lock, flags);
630 /* retry only "normal" I/O: */
631 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK)) {
633 spin_unlock_irqrestore(&ide_lock, flags);
634 ide_end_drive_cmd(drive, BUSY_STAT, 0);
637 if (rq->flags & REQ_DRIVE_TASKFILE) {
639 spin_unlock_irqrestore(&ide_lock, flags);
640 ide_end_drive_cmd(drive, BUSY_STAT, 0);
644 rq->errors |= ERROR_RESET;
645 spin_unlock_irqrestore(&ide_lock, flags);
646 DRIVER(drive)->end_request(drive, 0, 0);
651 * ide_cmd - issue a simple drive command
652 * @drive: drive the command is for
654 * @nsect: sector byte
655 * @handler: handler for the command completion
657 * Issue a simple drive command with interrupts.
658 * The drive must be selected beforehand.
661 static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect,
662 ide_handler_t *handler)
664 ide_hwif_t *hwif = HWIF(drive);
666 hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */
667 SELECT_MASK(drive,0);
668 hwif->OUTB(nsect,IDE_NSECTOR_REG);
669 ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL);
673 * drive_cmd_intr - drive command completion interrupt
674 * @drive: drive the completion interrupt occurred on
676 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
677 * We do any necessary daya reading and then wait for the drive to
678 * go non busy. At that point we may read the error data and complete
682 static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
684 struct request *rq = HWGROUP(drive)->rq;
685 ide_hwif_t *hwif = HWIF(drive);
686 u8 *args = (u8 *) rq->buffer;
687 u8 stat = hwif->INB(IDE_STATUS_REG);
691 if ((stat & DRQ_STAT) && args && args[3]) {
692 u8 io_32bit = drive->io_32bit;
694 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS);
695 drive->io_32bit = io_32bit;
696 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--)
700 if (!OK_STAT(stat, READY_STAT, BAD_STAT) && DRIVER(drive) != NULL)
701 return DRIVER(drive)->error(drive, "drive_cmd", stat);
702 /* calls ide_end_drive_cmd */
703 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
708 * do_special - issue some special commands
709 * @drive: drive the command is for
711 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT
712 * commands to a drive. It used to do much more, but has been scaled
716 static ide_startstop_t do_special (ide_drive_t *drive)
718 special_t *s = &drive->special;
721 printk("%s: do_special: 0x%02x\n", drive->name, s->all);
725 if (HWIF(drive)->tuneproc != NULL)
726 HWIF(drive)->tuneproc(drive, drive->tune_req);
730 return DRIVER(drive)->special(drive);
733 void ide_map_sg(ide_drive_t *drive, struct request *rq)
735 ide_hwif_t *hwif = drive->hwif;
736 struct scatterlist *sg = hwif->sg_table;
738 if (hwif->sg_mapped) /* needed by ide-scsi */
741 if ((rq->flags & REQ_DRIVE_TASKFILE) == 0) {
742 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg);
744 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE);
749 EXPORT_SYMBOL_GPL(ide_map_sg);
751 void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq)
753 ide_hwif_t *hwif = drive->hwif;
755 hwif->nsect = hwif->nleft = rq->nr_sectors;
756 hwif->cursg = hwif->cursg_ofs = 0;
759 EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
762 * execute_drive_command - issue special drive command
763 * @drive: the drive to issue th command on
764 * @rq: the request structure holding the command
766 * execute_drive_cmd() issues a special drive command, usually
767 * initiated by ioctl() from the external hdparm program. The
768 * command can be a drive command, drive task or taskfile
769 * operation. Weirdly you can call it with NULL to wait for
770 * all commands to finish. Don't do this as that is due to change
773 static ide_startstop_t execute_drive_cmd (ide_drive_t *drive,
776 ide_hwif_t *hwif = HWIF(drive);
777 if (rq->flags & REQ_DRIVE_TASKFILE) {
778 ide_task_t *args = rq->special;
783 hwif->data_phase = args->data_phase;
785 switch (hwif->data_phase) {
786 case TASKFILE_MULTI_OUT:
788 case TASKFILE_MULTI_IN:
790 ide_init_sg_cmd(drive, rq);
791 ide_map_sg(drive, rq);
796 if (args->tf_out_flags.all != 0)
797 return flagged_taskfile(drive, args);
798 return do_rw_taskfile(drive, args);
799 } else if (rq->flags & REQ_DRIVE_TASK) {
800 u8 *args = rq->buffer;
806 printk("%s: DRIVE_TASK_CMD ", drive->name);
807 printk("cmd=0x%02x ", args[0]);
808 printk("fr=0x%02x ", args[1]);
809 printk("ns=0x%02x ", args[2]);
810 printk("sc=0x%02x ", args[3]);
811 printk("lcyl=0x%02x ", args[4]);
812 printk("hcyl=0x%02x ", args[5]);
813 printk("sel=0x%02x\n", args[6]);
815 hwif->OUTB(args[1], IDE_FEATURE_REG);
816 hwif->OUTB(args[3], IDE_SECTOR_REG);
817 hwif->OUTB(args[4], IDE_LCYL_REG);
818 hwif->OUTB(args[5], IDE_HCYL_REG);
819 sel = (args[6] & ~0x10);
820 if (drive->select.b.unit)
822 hwif->OUTB(sel, IDE_SELECT_REG);
823 ide_cmd(drive, args[0], args[2], &drive_cmd_intr);
825 } else if (rq->flags & REQ_DRIVE_CMD) {
826 u8 *args = rq->buffer;
831 printk("%s: DRIVE_CMD ", drive->name);
832 printk("cmd=0x%02x ", args[0]);
833 printk("sc=0x%02x ", args[1]);
834 printk("fr=0x%02x ", args[2]);
835 printk("xx=0x%02x\n", args[3]);
837 if (args[0] == WIN_SMART) {
838 hwif->OUTB(0x4f, IDE_LCYL_REG);
839 hwif->OUTB(0xc2, IDE_HCYL_REG);
840 hwif->OUTB(args[2],IDE_FEATURE_REG);
841 hwif->OUTB(args[1],IDE_SECTOR_REG);
842 ide_cmd(drive, args[0], args[3], &drive_cmd_intr);
845 hwif->OUTB(args[2],IDE_FEATURE_REG);
846 ide_cmd(drive, args[0], args[1], &drive_cmd_intr);
852 * NULL is actually a valid way of waiting for
853 * all current requests to be flushed from the queue.
856 printk("%s: DRIVE_CMD (null)\n", drive->name);
858 ide_end_drive_cmd(drive,
859 hwif->INB(IDE_STATUS_REG),
860 hwif->INB(IDE_ERROR_REG));
865 * start_request - start of I/O and command issuing for IDE
867 * start_request() initiates handling of a new I/O request. It
868 * accepts commands and I/O (read/write) requests. It also does
869 * the final remapping for weird stuff like EZDrive. Once
870 * device mapper can work sector level the EZDrive stuff can go away
872 * FIXME: this function needs a rename
875 static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
877 ide_startstop_t startstop;
880 BUG_ON(!(rq->flags & REQ_STARTED));
883 printk("%s: start_request: current=0x%08lx\n",
884 HWIF(drive)->name, (unsigned long) rq);
887 /* bail early if we've exceeded max_failures */
888 if (drive->max_failures && (drive->failures > drive->max_failures)) {
893 * bail early if we've sent a device to sleep, however how to wake
894 * this needs to be a masked flag. FIXME for proper operations.
896 if (drive->suspend_reset)
900 if (blk_fs_request(rq) &&
901 (drive->media == ide_disk || drive->media == ide_floppy)) {
902 block += drive->sect0;
904 /* Yecch - this will shift the entire interval,
905 possibly killing some innocent following sector */
906 if (block == 0 && drive->remap_0_to_1 == 1)
907 block = 1; /* redirect MBR access to EZ-Drive partn table */
909 if (blk_pm_suspend_request(rq) &&
910 rq->pm->pm_step == ide_pm_state_start_suspend)
911 /* Mark drive blocked when starting the suspend sequence. */
913 else if (blk_pm_resume_request(rq) &&
914 rq->pm->pm_step == ide_pm_state_start_resume) {
916 * The first thing we do on wakeup is to wait for BSY bit to
917 * go away (with a looong timeout) as a drive on this hwif may
918 * just be POSTing itself.
919 * We do that before even selecting as the "other" device on
920 * the bus may be broken enough to walk on our toes at this
925 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
927 rc = ide_wait_not_busy(HWIF(drive), 35000);
929 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
931 HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]);
932 rc = ide_wait_not_busy(HWIF(drive), 10000);
934 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
938 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) {
939 printk(KERN_ERR "%s: drive not ready for command\n", drive->name);
942 if (!drive->special.all) {
943 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK))
944 return execute_drive_cmd(drive, rq);
945 else if (rq->flags & REQ_DRIVE_TASKFILE)
946 return execute_drive_cmd(drive, rq);
947 else if (blk_pm_request(rq)) {
949 printk("%s: start_power_step(step: %d)\n",
950 drive->name, rq->pm->pm_step);
952 startstop = DRIVER(drive)->start_power_step(drive, rq);
953 if (startstop == ide_stopped &&
954 rq->pm->pm_step == ide_pm_state_completed)
955 ide_complete_pm_request(drive, rq);
958 return (DRIVER(drive)->do_request(drive, rq, block));
960 return do_special(drive);
962 DRIVER(drive)->end_request(drive, 0, 0);
967 * ide_stall_queue - pause an IDE device
968 * @drive: drive to stall
969 * @timeout: time to stall for (jiffies)
971 * ide_stall_queue() can be used by a drive to give excess bandwidth back
972 * to the hwgroup by sleeping for timeout jiffies.
975 void ide_stall_queue (ide_drive_t *drive, unsigned long timeout)
977 if (timeout > WAIT_WORSTCASE)
978 timeout = WAIT_WORSTCASE;
979 drive->sleep = timeout + jiffies;
982 EXPORT_SYMBOL(ide_stall_queue);
984 #define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time)
987 * choose_drive - select a drive to service
988 * @hwgroup: hardware group to select on
990 * choose_drive() selects the next drive which will be serviced.
991 * This is necessary because the IDE layer can't issue commands
992 * to both drives on the same cable, unlike SCSI.
995 static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup)
997 ide_drive_t *drive, *best;
1001 drive = hwgroup->drive;
1004 * drive is doing pre-flush, ordered write, post-flush sequence. even
1005 * though that is 3 requests, it must be seen as a single transaction.
1006 * we must not preempt this drive until that is complete
1008 if (drive->doing_barrier) {
1010 * small race where queue could get replugged during
1011 * the 3-request flush cycle, just yank the plug since
1012 * we want it to finish asap
1014 blk_remove_plug(drive->queue);
1019 if ((!drive->sleep || time_after_eq(jiffies, drive->sleep))
1020 && !elv_queue_empty(drive->queue)) {
1022 || (drive->sleep && (!best->sleep || 0 < (signed long)(best->sleep - drive->sleep)))
1023 || (!best->sleep && 0 < (signed long)(WAKEUP(best) - WAKEUP(drive))))
1025 if (!blk_queue_plugged(drive->queue))
1029 } while ((drive = drive->next) != hwgroup->drive);
1030 if (best && best->nice1 && !best->sleep && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) {
1031 long t = (signed long)(WAKEUP(best) - jiffies);
1032 if (t >= WAIT_MIN_SLEEP) {
1034 * We *may* have some time to spare, but first let's see if
1035 * someone can potentially benefit from our nice mood today..
1040 /* FIXME: use time_before */
1041 && 0 < (signed long)(WAKEUP(drive) - (jiffies - best->service_time))
1042 && 0 < (signed long)((jiffies + t) - WAKEUP(drive)))
1044 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP));
1047 } while ((drive = drive->next) != best);
1054 * Issue a new request to a drive from hwgroup
1055 * Caller must have already done spin_lock_irqsave(&ide_lock, ..);
1057 * A hwgroup is a serialized group of IDE interfaces. Usually there is
1058 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640)
1059 * may have both interfaces in a single hwgroup to "serialize" access.
1060 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped
1061 * together into one hwgroup for serialized access.
1063 * Note also that several hwgroups can end up sharing a single IRQ,
1064 * possibly along with many other devices. This is especially common in
1065 * PCI-based systems with off-board IDE controller cards.
1067 * The IDE driver uses the single global ide_lock spinlock to protect
1068 * access to the request queues, and to protect the hwgroup->busy flag.
1070 * The first thread into the driver for a particular hwgroup sets the
1071 * hwgroup->busy flag to indicate that this hwgroup is now active,
1072 * and then initiates processing of the top request from the request queue.
1074 * Other threads attempting entry notice the busy setting, and will simply
1075 * queue their new requests and exit immediately. Note that hwgroup->busy
1076 * remains set even when the driver is merely awaiting the next interrupt.
1077 * Thus, the meaning is "this hwgroup is busy processing a request".
1079 * When processing of a request completes, the completing thread or IRQ-handler
1080 * will start the next request from the queue. If no more work remains,
1081 * the driver will clear the hwgroup->busy flag and exit.
1083 * The ide_lock (spinlock) is used to protect all access to the
1084 * hwgroup->busy flag, but is otherwise not needed for most processing in
1085 * the driver. This makes the driver much more friendlier to shared IRQs
1086 * than previous designs, while remaining 100% (?) SMP safe and capable.
1088 static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
1093 ide_startstop_t startstop;
1095 /* for atari only: POSSIBLY BROKEN HERE(?) */
1096 ide_get_lock(ide_intr, hwgroup);
1098 /* caller must own ide_lock */
1099 BUG_ON(!irqs_disabled());
1101 while (!hwgroup->busy) {
1103 drive = choose_drive(hwgroup);
1104 if (drive == NULL) {
1105 unsigned long sleep = 0;
1107 drive = hwgroup->drive;
1109 if (drive->sleep && (!sleep || 0 < (signed long)(sleep - drive->sleep)))
1110 sleep = drive->sleep;
1111 } while ((drive = drive->next) != hwgroup->drive);
1114 * Take a short snooze, and then wake up this hwgroup again.
1115 * This gives other hwgroups on the same a chance to
1116 * play fairly with us, just in case there are big differences
1117 * in relative throughputs.. don't want to hog the cpu too much.
1119 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP))
1120 sleep = jiffies + WAIT_MIN_SLEEP;
1122 if (timer_pending(&hwgroup->timer))
1123 printk(KERN_CRIT "ide_set_handler: timer already active\n");
1125 /* so that ide_timer_expiry knows what to do */
1126 hwgroup->sleeping = 1;
1127 mod_timer(&hwgroup->timer, sleep);
1128 /* we purposely leave hwgroup->busy==1
1131 /* Ugly, but how can we sleep for the lock
1132 * otherwise? perhaps from tq_disk?
1135 /* for atari only */
1140 /* no more work for this hwgroup (for now) */
1144 if (hwgroup->hwif->sharing_irq &&
1145 hwif != hwgroup->hwif &&
1146 hwif->io_ports[IDE_CONTROL_OFFSET]) {
1147 /* set nIEN for previous hwif */
1148 SELECT_INTERRUPT(drive);
1150 hwgroup->hwif = hwif;
1151 hwgroup->drive = drive;
1153 drive->service_start = jiffies;
1155 if (blk_queue_plugged(drive->queue)) {
1156 printk(KERN_ERR "ide: huh? queue was plugged!\n");
1161 * we know that the queue isn't empty, but this can happen
1162 * if the q->prep_rq_fn() decides to kill a request
1164 rq = elv_next_request(drive->queue);
1171 * if rq is a barrier write, issue pre cache flush if not
1174 if (blk_barrier_rq(rq) && !blk_barrier_preflush(rq))
1175 rq = ide_queue_flush_cmd(drive, rq, 0);
1178 * Sanity: don't accept a request that isn't a PM request
1179 * if we are currently power managed. This is very important as
1180 * blk_stop_queue() doesn't prevent the elv_next_request()
1181 * above to return us whatever is in the queue. Since we call
1182 * ide_do_request() ourselves, we end up taking requests while
1183 * the queue is blocked...
1185 * We let requests forced at head of queue with ide-preempt
1186 * though. I hope that doesn't happen too much, hopefully not
1187 * unless the subdriver triggers such a thing in its own PM
1190 if (drive->blocked && !blk_pm_request(rq) && !(rq->flags & REQ_PREEMPT)) {
1191 /* We clear busy, there should be no pending ATA command at this point. */
1199 * Some systems have trouble with IDE IRQs arriving while
1200 * the driver is still setting things up. So, here we disable
1201 * the IRQ used by this interface while the request is being started.
1202 * This may look bad at first, but pretty much the same thing
1203 * happens anyway when any interrupt comes in, IDE or otherwise
1204 * -- the kernel masks the IRQ while it is being handled.
1206 if (hwif->irq != masked_irq)
1207 disable_irq_nosync(hwif->irq);
1208 spin_unlock(&ide_lock);
1210 /* allow other IRQs while we start this request */
1211 startstop = start_request(drive, rq);
1212 spin_lock_irq(&ide_lock);
1213 if (hwif->irq != masked_irq)
1214 enable_irq(hwif->irq);
1215 if (startstop == ide_stopped)
1221 * Passes the stuff to ide_do_request
1223 void do_ide_request(request_queue_t *q)
1225 ide_drive_t *drive = q->queuedata;
1227 ide_do_request(HWGROUP(drive), IDE_NO_IRQ);
1231 * un-busy the hwgroup etc, and clear any pending DMA status. we want to
1232 * retry the current request in pio mode instead of risking tossing it
1235 static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error)
1237 ide_hwif_t *hwif = HWIF(drive);
1239 ide_startstop_t ret = ide_stopped;
1242 * end current dma transaction
1246 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name);
1247 (void)HWIF(drive)->ide_dma_end(drive);
1248 ret = DRIVER(drive)->error(drive, "dma timeout error",
1249 hwif->INB(IDE_STATUS_REG));
1251 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name);
1252 (void) hwif->ide_dma_timeout(drive);
1256 * disable dma for now, but remember that we did so because of
1257 * a timeout -- we'll reenable after we finish this next request
1258 * (or rather the first chunk of it) in pio.
1261 drive->state = DMA_PIO_RETRY;
1262 (void) hwif->ide_dma_off_quietly(drive);
1265 * un-busy drive etc (hwgroup->busy is cleared on return) and
1266 * make sure request is sane
1268 rq = HWGROUP(drive)->rq;
1269 HWGROUP(drive)->rq = NULL;
1276 rq->sector = rq->bio->bi_sector;
1277 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9;
1278 rq->hard_cur_sectors = rq->current_nr_sectors;
1279 rq->buffer = bio_data(rq->bio);
1285 * ide_timer_expiry - handle lack of an IDE interrupt
1286 * @data: timer callback magic (hwgroup)
1288 * An IDE command has timed out before the expected drive return
1289 * occurred. At this point we attempt to clean up the current
1290 * mess. If the current handler includes an expiry handler then
1291 * we invoke the expiry handler, and providing it is happy the
1292 * work is done. If that fails we apply generic recovery rules
1293 * invoking the handler and checking the drive DMA status. We
1294 * have an excessively incestuous relationship with the DMA
1295 * logic that wants cleaning up.
1298 void ide_timer_expiry (unsigned long data)
1300 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data;
1301 ide_handler_t *handler;
1302 ide_expiry_t *expiry;
1303 unsigned long flags;
1304 unsigned long wait = -1;
1306 spin_lock_irqsave(&ide_lock, flags);
1308 if ((handler = hwgroup->handler) == NULL) {
1310 * Either a marginal timeout occurred
1311 * (got the interrupt just as timer expired),
1312 * or we were "sleeping" to give other devices a chance.
1313 * Either way, we don't really want to complain about anything.
1315 if (hwgroup->sleeping) {
1316 hwgroup->sleeping = 0;
1320 ide_drive_t *drive = hwgroup->drive;
1322 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n");
1323 hwgroup->handler = NULL;
1326 ide_startstop_t startstop = ide_stopped;
1327 if (!hwgroup->busy) {
1328 hwgroup->busy = 1; /* paranoia */
1329 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name);
1331 if ((expiry = hwgroup->expiry) != NULL) {
1333 if ((wait = expiry(drive)) > 0) {
1335 hwgroup->timer.expires = jiffies + wait;
1336 add_timer(&hwgroup->timer);
1337 spin_unlock_irqrestore(&ide_lock, flags);
1341 hwgroup->handler = NULL;
1343 * We need to simulate a real interrupt when invoking
1344 * the handler() function, which means we need to
1345 * globally mask the specific IRQ:
1347 spin_unlock(&ide_lock);
1349 #if DISABLE_IRQ_NOSYNC
1350 disable_irq_nosync(hwif->irq);
1352 /* disable_irq_nosync ?? */
1353 disable_irq(hwif->irq);
1354 #endif /* DISABLE_IRQ_NOSYNC */
1356 * as if we were handling an interrupt */
1357 local_irq_disable();
1358 if (hwgroup->poll_timeout != 0) {
1359 startstop = handler(drive);
1360 } else if (drive_is_ready(drive)) {
1361 if (drive->waiting_for_dma)
1362 (void) hwgroup->hwif->ide_dma_lostirq(drive);
1363 (void)ide_ack_intr(hwif);
1364 printk(KERN_WARNING "%s: lost interrupt\n", drive->name);
1365 startstop = handler(drive);
1367 if (drive->waiting_for_dma) {
1368 startstop = ide_dma_timeout_retry(drive, wait);
1371 DRIVER(drive)->error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG));
1373 drive->service_time = jiffies - drive->service_start;
1374 spin_lock_irq(&ide_lock);
1375 enable_irq(hwif->irq);
1376 if (startstop == ide_stopped)
1380 ide_do_request(hwgroup, IDE_NO_IRQ);
1381 spin_unlock_irqrestore(&ide_lock, flags);
1385 * unexpected_intr - handle an unexpected IDE interrupt
1386 * @irq: interrupt line
1387 * @hwgroup: hwgroup being processed
1389 * There's nothing really useful we can do with an unexpected interrupt,
1390 * other than reading the status register (to clear it), and logging it.
1391 * There should be no way that an irq can happen before we're ready for it,
1392 * so we needn't worry much about losing an "important" interrupt here.
1394 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever
1395 * the drive enters "idle", "standby", or "sleep" mode, so if the status
1396 * looks "good", we just ignore the interrupt completely.
1398 * This routine assumes __cli() is in effect when called.
1400 * If an unexpected interrupt happens on irq15 while we are handling irq14
1401 * and if the two interfaces are "serialized" (CMD640), then it looks like
1402 * we could screw up by interfering with a new request being set up for
1405 * In reality, this is a non-issue. The new command is not sent unless
1406 * the drive is ready to accept one, in which case we know the drive is
1407 * not trying to interrupt us. And ide_set_handler() is always invoked
1408 * before completing the issuance of any new drive command, so we will not
1409 * be accidentally invoked as a result of any valid command completion
1412 * Note that we must walk the entire hwgroup here. We know which hwif
1413 * is doing the current command, but we don't know which hwif burped
1417 static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup)
1420 ide_hwif_t *hwif = hwgroup->hwif;
1423 * handle the unexpected interrupt
1426 if (hwif->irq == irq) {
1427 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1428 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) {
1429 /* Try to not flood the console with msgs */
1430 static unsigned long last_msgtime, count;
1432 if (time_after(jiffies, last_msgtime + HZ)) {
1433 last_msgtime = jiffies;
1434 printk(KERN_ERR "%s%s: unexpected interrupt, "
1435 "status=0x%02x, count=%ld\n",
1437 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count);
1441 } while ((hwif = hwif->next) != hwgroup->hwif);
1445 * ide_intr - default IDE interrupt handler
1446 * @irq: interrupt number
1447 * @dev_id: hwif group
1448 * @regs: unused weirdness from the kernel irq layer
1450 * This is the default IRQ handler for the IDE layer. You should
1451 * not need to override it. If you do be aware it is subtle in
1454 * hwgroup->hwif is the interface in the group currently performing
1455 * a command. hwgroup->drive is the drive and hwgroup->handler is
1456 * the IRQ handler to call. As we issue a command the handlers
1457 * step through multiple states, reassigning the handler to the
1458 * next step in the process. Unlike a smart SCSI controller IDE
1459 * expects the main processor to sequence the various transfer
1460 * stages. We also manage a poll timer to catch up with most
1461 * timeout situations. There are still a few where the handlers
1462 * don't ever decide to give up.
1464 * The handler eventually returns ide_stopped to indicate the
1465 * request completed. At this point we issue the next request
1466 * on the hwgroup and the process begins again.
1469 irqreturn_t ide_intr (int irq, void *dev_id, struct pt_regs *regs)
1471 unsigned long flags;
1472 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id;
1475 ide_handler_t *handler;
1476 ide_startstop_t startstop;
1478 spin_lock_irqsave(&ide_lock, flags);
1479 hwif = hwgroup->hwif;
1481 if (!ide_ack_intr(hwif)) {
1482 spin_unlock_irqrestore(&ide_lock, flags);
1486 if (hwif->polling) {
1487 /* We took an interrupt during a polled drive retune.
1488 This should go away eventually when that code uses
1489 the polling logic like do_reset1 */
1490 spin_unlock_irqrestore(&ide_lock, flags);
1493 if ((handler = hwgroup->handler) == NULL ||
1494 hwgroup->poll_timeout != 0) {
1496 * Not expecting an interrupt from this drive.
1497 * That means this could be:
1498 * (1) an interrupt from another PCI device
1499 * sharing the same PCI INT# as us.
1500 * or (2) a drive just entered sleep or standby mode,
1501 * and is interrupting to let us know.
1502 * or (3) a spurious interrupt of unknown origin.
1504 * For PCI, we cannot tell the difference,
1505 * so in that case we just ignore it and hope it goes away.
1507 * FIXME: unexpected_intr should be hwif-> then we can
1508 * remove all the ifdef PCI crap
1510 #ifdef CONFIG_BLK_DEV_IDEPCI
1511 if (hwif->pci_dev && !hwif->pci_dev->vendor)
1512 #endif /* CONFIG_BLK_DEV_IDEPCI */
1515 * Probably not a shared PCI interrupt,
1516 * so we can safely try to do something about it:
1518 unexpected_intr(irq, hwgroup);
1519 #ifdef CONFIG_BLK_DEV_IDEPCI
1522 * Whack the status register, just in case
1523 * we have a leftover pending IRQ.
1525 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
1526 #endif /* CONFIG_BLK_DEV_IDEPCI */
1528 spin_unlock_irqrestore(&ide_lock, flags);
1531 drive = hwgroup->drive;
1534 * This should NEVER happen, and there isn't much
1535 * we could do about it here.
1537 * [Note - this can occur if the drive is hot unplugged]
1539 spin_unlock_irqrestore(&ide_lock, flags);
1542 if (!drive_is_ready(drive)) {
1544 * This happens regularly when we share a PCI IRQ with
1545 * another device. Unfortunately, it can also happen
1546 * with some buggy drives that trigger the IRQ before
1547 * their status register is up to date. Hopefully we have
1548 * enough advance overhead that the latter isn't a problem.
1550 spin_unlock_irqrestore(&ide_lock, flags);
1553 if (!hwgroup->busy) {
1554 hwgroup->busy = 1; /* paranoia */
1555 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name);
1557 hwgroup->handler = NULL;
1558 del_timer(&hwgroup->timer);
1559 spin_unlock(&ide_lock);
1563 /* service this interrupt, may set handler for next interrupt */
1564 startstop = handler(drive);
1565 spin_lock_irq(&ide_lock);
1568 * Note that handler() may have set things up for another
1569 * interrupt to occur soon, but it cannot happen until
1570 * we exit from this routine, because it will be the
1571 * same irq as is currently being serviced here, and Linux
1572 * won't allow another of the same (on any CPU) until we return.
1574 drive->service_time = jiffies - drive->service_start;
1575 if (startstop == ide_stopped) {
1576 if (hwgroup->handler == NULL) { /* paranoia */
1578 ide_do_request(hwgroup, hwif->irq);
1580 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler "
1581 "on exit\n", drive->name);
1584 spin_unlock_irqrestore(&ide_lock, flags);
1589 * ide_init_drive_cmd - initialize a drive command request
1590 * @rq: request object
1592 * Initialize a request before we fill it in and send it down to
1593 * ide_do_drive_cmd. Commands must be set up by this function. Right
1594 * now it doesn't do a lot, but if that changes abusers will have a
1598 void ide_init_drive_cmd (struct request *rq)
1600 memset(rq, 0, sizeof(*rq));
1601 rq->flags = REQ_DRIVE_CMD;
1605 EXPORT_SYMBOL(ide_init_drive_cmd);
1608 * ide_do_drive_cmd - issue IDE special command
1609 * @drive: device to issue command
1610 * @rq: request to issue
1611 * @action: action for processing
1613 * This function issues a special IDE device request
1614 * onto the request queue.
1616 * If action is ide_wait, then the rq is queued at the end of the
1617 * request queue, and the function sleeps until it has been processed.
1618 * This is for use when invoked from an ioctl handler.
1620 * If action is ide_preempt, then the rq is queued at the head of
1621 * the request queue, displacing the currently-being-processed
1622 * request and this function returns immediately without waiting
1623 * for the new rq to be completed. This is VERY DANGEROUS, and is
1624 * intended for careful use by the ATAPI tape/cdrom driver code.
1626 * If action is ide_next, then the rq is queued immediately after
1627 * the currently-being-processed-request (if any), and the function
1628 * returns without waiting for the new rq to be completed. As above,
1629 * This is VERY DANGEROUS, and is intended for careful use by the
1630 * ATAPI tape/cdrom driver code.
1632 * If action is ide_end, then the rq is queued at the end of the
1633 * request queue, and the function returns immediately without waiting
1634 * for the new rq to be completed. This is again intended for careful
1635 * use by the ATAPI tape/cdrom driver code.
1638 int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action)
1640 unsigned long flags;
1641 ide_hwgroup_t *hwgroup = HWGROUP(drive);
1642 DECLARE_COMPLETION(wait);
1643 int where = ELEVATOR_INSERT_BACK, err;
1644 int must_wait = (action == ide_wait || action == ide_head_wait);
1647 rq->rq_status = RQ_ACTIVE;
1649 rq->rq_disk = drive->disk;
1652 * we need to hold an extra reference to request for safe inspection
1657 rq->waiting = &wait;
1660 spin_lock_irqsave(&ide_lock, flags);
1661 if (action == ide_preempt)
1663 if (action == ide_preempt || action == ide_head_wait) {
1664 where = ELEVATOR_INSERT_FRONT;
1665 rq->flags |= REQ_PREEMPT;
1667 __elv_add_request(drive->queue, rq, where, 0);
1668 ide_do_request(hwgroup, IDE_NO_IRQ);
1669 spin_unlock_irqrestore(&ide_lock, flags);
1673 wait_for_completion(&wait);
1678 blk_put_request(rq);
1684 EXPORT_SYMBOL(ide_do_drive_cmd);