linux-hardened/drivers/ide/ide-atapi.c
Tejun Heo 9934c8c045 block: implement and enforce request peek/start/fetch
Till now block layer allowed two separate modes of request execution.
A request is always acquired from the request queue via
elv_next_request().  After that, drivers are free to either dequeue it
or process it without dequeueing.  Dequeue allows elv_next_request()
to return the next request so that multiple requests can be in flight.

Executing requests without dequeueing has its merits mostly in
allowing drivers for simpler devices which can't do sg to deal with
segments only without considering request boundary.  However, the
benefit this brings is dubious and declining while the cost of the API
ambiguity is increasing.  Segment based drivers are usually for very
old or limited devices and as converting to dequeueing model isn't
difficult, it doesn't justify the API overhead it puts on block layer
and its more modern users.

Previous patches converted all block low level drivers to dequeueing
model.  This patch completes the API transition by...

* renaming elv_next_request() to blk_peek_request()

* renaming blkdev_dequeue_request() to blk_start_request()

* adding blk_fetch_request() which is combination of peek and start

* disallowing completion of queued (not started) requests

* applying new API to all LLDs

Renamings are for consistency and to break out of tree code so that
it's apparent that out of tree drivers need updating.

[ Impact: block request issue API cleanup, no functional change ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: unsik Kim <donari75@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Laurent Vivier <Laurent@lvivier.info>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: Pierre Ossman <drzeus@drzeus.cx>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Stefan Weinhuber <wein@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:52:18 +02:00

683 lines
17 KiB
C

/*
* ATAPI support.
*/
#include <linux/kernel.h>
#include <linux/cdrom.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/scatterlist.h>
#include <scsi/scsi.h>
#ifdef DEBUG
#define debug_log(fmt, args...) \
printk(KERN_INFO "ide: " fmt, ## args)
#else
#define debug_log(fmt, args...) do {} while (0)
#endif
#define ATAPI_MIN_CDB_BYTES 12
static inline int dev_is_idecd(ide_drive_t *drive)
{
return drive->media == ide_cdrom || drive->media == ide_optical;
}
/*
* Check whether we can support a device,
* based on the ATAPI IDENTIFY command results.
*/
int ide_check_atapi_device(ide_drive_t *drive, const char *s)
{
u16 *id = drive->id;
u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
*((u16 *)&gcw) = id[ATA_ID_CONFIG];
protocol = (gcw[1] & 0xC0) >> 6;
device_type = gcw[1] & 0x1F;
removable = (gcw[0] & 0x80) >> 7;
drq_type = (gcw[0] & 0x60) >> 5;
packet_size = gcw[0] & 0x03;
#ifdef CONFIG_PPC
/* kludge for Apple PowerBook internal zip */
if (drive->media == ide_floppy && device_type == 5 &&
!strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
strstr((char *)&id[ATA_ID_PROD], "ZIP"))
device_type = 0;
#endif
if (protocol != 2)
printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
s, drive->name, protocol);
else if ((drive->media == ide_floppy && device_type != 0) ||
(drive->media == ide_tape && device_type != 1))
printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
s, drive->name, device_type);
else if (removable == 0)
printk(KERN_ERR "%s: %s: the removable flag is not set\n",
s, drive->name);
else if (drive->media == ide_floppy && drq_type == 3)
printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
"supported\n", s, drive->name, drq_type);
else if (packet_size != 0)
printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
"bytes\n", s, drive->name, packet_size);
else
return 1;
return 0;
}
EXPORT_SYMBOL_GPL(ide_check_atapi_device);
void ide_init_pc(struct ide_atapi_pc *pc)
{
memset(pc, 0, sizeof(*pc));
pc->buf = pc->pc_buf;
pc->buf_size = IDE_PC_BUFFER_SIZE;
}
EXPORT_SYMBOL_GPL(ide_init_pc);
/*
* Add a special packet command request to the tail of the request queue,
* and wait for it to be serviced.
*/
int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
struct ide_atapi_pc *pc)
{
struct request *rq;
int error;
rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
rq->cmd_type = REQ_TYPE_SPECIAL;
rq->special = (char *)pc;
if (pc->req_xfer) {
error = blk_rq_map_kern(drive->queue, rq, pc->buf, pc->req_xfer,
GFP_NOIO);
if (error)
goto put_req;
}
memcpy(rq->cmd, pc->c, 12);
if (drive->media == ide_tape)
rq->cmd[13] = REQ_IDETAPE_PC1;
error = blk_execute_rq(drive->queue, disk, rq, 0);
put_req:
blk_put_request(rq);
return error;
}
EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
{
struct ide_atapi_pc pc;
ide_init_pc(&pc);
pc.c[0] = TEST_UNIT_READY;
return ide_queue_pc_tail(drive, disk, &pc);
}
EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
{
struct ide_atapi_pc pc;
ide_init_pc(&pc);
pc.c[0] = START_STOP;
pc.c[4] = start;
if (drive->media == ide_tape)
pc.flags |= PC_FLAG_WAIT_FOR_DSC;
return ide_queue_pc_tail(drive, disk, &pc);
}
EXPORT_SYMBOL_GPL(ide_do_start_stop);
int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
{
struct ide_atapi_pc pc;
if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0)
return 0;
ide_init_pc(&pc);
pc.c[0] = ALLOW_MEDIUM_REMOVAL;
pc.c[4] = on;
return ide_queue_pc_tail(drive, disk, &pc);
}
EXPORT_SYMBOL_GPL(ide_set_media_lock);
void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
{
ide_init_pc(pc);
pc->c[0] = REQUEST_SENSE;
if (drive->media == ide_floppy) {
pc->c[4] = 255;
pc->req_xfer = 18;
} else {
pc->c[4] = 20;
pc->req_xfer = 20;
}
}
EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
void ide_prep_sense(ide_drive_t *drive, struct request *rq)
{
struct request_sense *sense = &drive->sense_data;
struct request *sense_rq = &drive->sense_rq;
unsigned int cmd_len, sense_len;
int err;
debug_log("%s: enter\n", __func__);
switch (drive->media) {
case ide_floppy:
cmd_len = 255;
sense_len = 18;
break;
case ide_tape:
cmd_len = 20;
sense_len = 20;
break;
default:
cmd_len = 18;
sense_len = 18;
}
BUG_ON(sense_len > sizeof(*sense));
if (blk_sense_request(rq) || drive->sense_rq_armed)
return;
memset(sense, 0, sizeof(*sense));
blk_rq_init(rq->q, sense_rq);
err = blk_rq_map_kern(drive->queue, sense_rq, sense, sense_len,
GFP_NOIO);
if (unlikely(err)) {
if (printk_ratelimit())
printk(KERN_WARNING "%s: failed to map sense buffer\n",
drive->name);
return;
}
sense_rq->rq_disk = rq->rq_disk;
sense_rq->cmd[0] = GPCMD_REQUEST_SENSE;
sense_rq->cmd[4] = cmd_len;
sense_rq->cmd_type = REQ_TYPE_SENSE;
sense_rq->cmd_flags |= REQ_PREEMPT;
if (drive->media == ide_tape)
sense_rq->cmd[13] = REQ_IDETAPE_PC1;
drive->sense_rq_armed = true;
}
EXPORT_SYMBOL_GPL(ide_prep_sense);
int ide_queue_sense_rq(ide_drive_t *drive, void *special)
{
/* deferred failure from ide_prep_sense() */
if (!drive->sense_rq_armed) {
printk(KERN_WARNING "%s: failed queue sense request\n",
drive->name);
return -ENOMEM;
}
drive->sense_rq.special = special;
drive->sense_rq_armed = false;
drive->hwif->rq = NULL;
elv_add_request(drive->queue, &drive->sense_rq,
ELEVATOR_INSERT_FRONT, 0);
return 0;
}
EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
/*
* Called when an error was detected during the last packet command.
* We queue a request sense packet command at the head of the request
* queue.
*/
void ide_retry_pc(ide_drive_t *drive)
{
struct request *failed_rq = drive->hwif->rq;
struct request *sense_rq = &drive->sense_rq;
struct ide_atapi_pc *pc = &drive->request_sense_pc;
(void)ide_read_error(drive);
/* init pc from sense_rq */
ide_init_pc(pc);
memcpy(pc->c, sense_rq->cmd, 12);
pc->buf = bio_data(sense_rq->bio); /* pointer to mapped address */
pc->req_xfer = blk_rq_bytes(sense_rq);
if (drive->media == ide_tape)
set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
/*
* Push back the failed request and put request sense on top
* of it. The failed command will be retried after sense data
* is acquired.
*/
blk_requeue_request(failed_rq->q, failed_rq);
drive->hwif->rq = NULL;
if (ide_queue_sense_rq(drive, pc)) {
blk_start_request(failed_rq);
ide_complete_rq(drive, -EIO, blk_rq_bytes(failed_rq));
}
}
EXPORT_SYMBOL_GPL(ide_retry_pc);
int ide_cd_expiry(ide_drive_t *drive)
{
struct request *rq = drive->hwif->rq;
unsigned long wait = 0;
debug_log("%s: rq->cmd[0]: 0x%x\n", __func__, rq->cmd[0]);
/*
* Some commands are *slow* and normally take a long time to complete.
* Usually we can use the ATAPI "disconnect" to bypass this, but not all
* commands/drives support that. Let ide_timer_expiry keep polling us
* for these.
*/
switch (rq->cmd[0]) {
case GPCMD_BLANK:
case GPCMD_FORMAT_UNIT:
case GPCMD_RESERVE_RZONE_TRACK:
case GPCMD_CLOSE_TRACK:
case GPCMD_FLUSH_CACHE:
wait = ATAPI_WAIT_PC;
break;
default:
if (!(rq->cmd_flags & REQ_QUIET))
printk(KERN_INFO "cmd 0x%x timed out\n",
rq->cmd[0]);
wait = 0;
break;
}
return wait;
}
EXPORT_SYMBOL_GPL(ide_cd_expiry);
int ide_cd_get_xferlen(struct request *rq)
{
if (blk_fs_request(rq))
return 32768;
else if (blk_sense_request(rq) || blk_pc_request(rq) ||
rq->cmd_type == REQ_TYPE_ATA_PC)
return blk_rq_bytes(rq);
else
return 0;
}
EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason)
{
struct ide_taskfile tf;
drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT |
IDE_VALID_LBAM | IDE_VALID_LBAH);
*bcount = (tf.lbah << 8) | tf.lbam;
*ireason = tf.nsect & 3;
}
EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason);
/*
* This is the usual interrupt handler which will be called during a packet
* command. We will transfer some of the data (as requested by the drive)
* and will re-point interrupt handler to us.
*/
static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
{
struct ide_atapi_pc *pc = drive->pc;
ide_hwif_t *hwif = drive->hwif;
struct ide_cmd *cmd = &hwif->cmd;
struct request *rq = hwif->rq;
const struct ide_tp_ops *tp_ops = hwif->tp_ops;
unsigned int timeout, done;
u16 bcount;
u8 stat, ireason, dsc = 0;
u8 write = !!(pc->flags & PC_FLAG_WRITING);
debug_log("Enter %s - interrupt handler\n", __func__);
timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
: WAIT_TAPE_CMD;
/* Clear the interrupt */
stat = tp_ops->read_status(hwif);
if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
int rc;
drive->waiting_for_dma = 0;
rc = hwif->dma_ops->dma_end(drive);
ide_dma_unmap_sg(drive, cmd);
if (rc || (drive->media == ide_tape && (stat & ATA_ERR))) {
if (drive->media == ide_floppy)
printk(KERN_ERR "%s: DMA %s error\n",
drive->name, rq_data_dir(pc->rq)
? "write" : "read");
pc->flags |= PC_FLAG_DMA_ERROR;
} else
pc->xferred = pc->req_xfer;
debug_log("%s: DMA finished\n", drive->name);
}
/* No more interrupts */
if ((stat & ATA_DRQ) == 0) {
int uptodate, error;
debug_log("Packet command completed, %d bytes transferred\n",
pc->xferred);
pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
local_irq_enable_in_hardirq();
if (drive->media == ide_tape &&
(stat & ATA_ERR) && rq->cmd[0] == REQUEST_SENSE)
stat &= ~ATA_ERR;
if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
/* Error detected */
debug_log("%s: I/O error\n", drive->name);
if (drive->media != ide_tape)
pc->rq->errors++;
if (rq->cmd[0] == REQUEST_SENSE) {
printk(KERN_ERR "%s: I/O error in request sense"
" command\n", drive->name);
return ide_do_reset(drive);
}
debug_log("[cmd %x]: check condition\n", rq->cmd[0]);
/* Retry operation */
ide_retry_pc(drive);
/* queued, but not started */
return ide_stopped;
}
pc->error = 0;
if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
dsc = 1;
/* Command finished - Call the callback function */
uptodate = drive->pc_callback(drive, dsc);
if (uptodate == 0)
drive->failed_pc = NULL;
if (blk_special_request(rq)) {
rq->errors = 0;
error = 0;
} else {
if (blk_fs_request(rq) == 0 && uptodate <= 0) {
if (rq->errors == 0)
rq->errors = -EIO;
}
error = uptodate ? 0 : -EIO;
}
ide_complete_rq(drive, error, blk_rq_bytes(rq));
return ide_stopped;
}
if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
printk(KERN_ERR "%s: The device wants to issue more interrupts "
"in DMA mode\n", drive->name);
ide_dma_off(drive);
return ide_do_reset(drive);
}
/* Get the number of bytes to transfer on this interrupt. */
ide_read_bcount_and_ireason(drive, &bcount, &ireason);
if (ireason & ATAPI_COD) {
printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
return ide_do_reset(drive);
}
if (((ireason & ATAPI_IO) == ATAPI_IO) == write) {
/* Hopefully, we will never get here */
printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
"to %s!\n", drive->name,
(ireason & ATAPI_IO) ? "Write" : "Read",
(ireason & ATAPI_IO) ? "Read" : "Write");
return ide_do_reset(drive);
}
done = min_t(unsigned int, bcount, cmd->nleft);
ide_pio_bytes(drive, cmd, write, done);
/* Update transferred byte count */
pc->xferred += done;
bcount -= done;
if (bcount)
ide_pad_transfer(drive, write, bcount);
debug_log("[cmd %x] transferred %d bytes, padded %d bytes\n",
rq->cmd[0], done, bcount);
/* And set the interrupt handler again */
ide_set_handler(drive, ide_pc_intr, timeout);
return ide_started;
}
static void ide_init_packet_cmd(struct ide_cmd *cmd, u8 valid_tf,
u16 bcount, u8 dma)
{
cmd->protocol = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
cmd->valid.out.tf = IDE_VALID_LBAH | IDE_VALID_LBAM |
IDE_VALID_FEATURE | valid_tf;
cmd->tf.command = ATA_CMD_PACKET;
cmd->tf.feature = dma; /* Use PIO/DMA */
cmd->tf.lbam = bcount & 0xff;
cmd->tf.lbah = (bcount >> 8) & 0xff;
}
static u8 ide_read_ireason(ide_drive_t *drive)
{
struct ide_taskfile tf;
drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT);
return tf.nsect & 3;
}
static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
{
int retries = 100;
while (retries-- && ((ireason & ATAPI_COD) == 0 ||
(ireason & ATAPI_IO))) {
printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
"a packet command, retrying\n", drive->name);
udelay(100);
ireason = ide_read_ireason(drive);
if (retries == 0) {
printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
"a packet command, ignoring\n",
drive->name);
ireason |= ATAPI_COD;
ireason &= ~ATAPI_IO;
}
}
return ireason;
}
static int ide_delayed_transfer_pc(ide_drive_t *drive)
{
/* Send the actual packet */
drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
/* Timeout for the packet command */
return WAIT_FLOPPY_CMD;
}
static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
{
struct ide_atapi_pc *uninitialized_var(pc);
ide_hwif_t *hwif = drive->hwif;
struct request *rq = hwif->rq;
ide_expiry_t *expiry;
unsigned int timeout;
int cmd_len;
ide_startstop_t startstop;
u8 ireason;
if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
printk(KERN_ERR "%s: Strange, packet command initiated yet "
"DRQ isn't asserted\n", drive->name);
return startstop;
}
if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
if (drive->dma)
drive->waiting_for_dma = 1;
}
if (dev_is_idecd(drive)) {
/* ATAPI commands get padded out to 12 bytes minimum */
cmd_len = COMMAND_SIZE(rq->cmd[0]);
if (cmd_len < ATAPI_MIN_CDB_BYTES)
cmd_len = ATAPI_MIN_CDB_BYTES;
timeout = rq->timeout;
expiry = ide_cd_expiry;
} else {
pc = drive->pc;
cmd_len = ATAPI_MIN_CDB_BYTES;
/*
* If necessary schedule the packet transfer to occur 'timeout'
* miliseconds later in ide_delayed_transfer_pc() after the
* device says it's ready for a packet.
*/
if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
timeout = drive->pc_delay;
expiry = &ide_delayed_transfer_pc;
} else {
timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
: WAIT_TAPE_CMD;
expiry = NULL;
}
ireason = ide_read_ireason(drive);
if (drive->media == ide_tape)
ireason = ide_wait_ireason(drive, ireason);
if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
"a packet command\n", drive->name);
return ide_do_reset(drive);
}
}
hwif->expiry = expiry;
/* Set the interrupt routine */
ide_set_handler(drive,
(dev_is_idecd(drive) ? drive->irq_handler
: ide_pc_intr),
timeout);
/* Send the actual packet */
if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
hwif->tp_ops->output_data(drive, NULL, rq->cmd, cmd_len);
/* Begin DMA, if necessary */
if (dev_is_idecd(drive)) {
if (drive->dma)
hwif->dma_ops->dma_start(drive);
} else {
if (pc->flags & PC_FLAG_DMA_OK) {
pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
hwif->dma_ops->dma_start(drive);
}
}
return ide_started;
}
ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd)
{
struct ide_atapi_pc *pc;
ide_hwif_t *hwif = drive->hwif;
ide_expiry_t *expiry = NULL;
struct request *rq = hwif->rq;
unsigned int timeout;
u16 bcount;
u8 valid_tf;
u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);
if (dev_is_idecd(drive)) {
valid_tf = IDE_VALID_NSECT | IDE_VALID_LBAL;
bcount = ide_cd_get_xferlen(rq);
expiry = ide_cd_expiry;
timeout = ATAPI_WAIT_PC;
if (drive->dma)
drive->dma = !ide_dma_prepare(drive, cmd);
} else {
pc = drive->pc;
/* We haven't transferred any data yet */
pc->xferred = 0;
valid_tf = IDE_VALID_DEVICE;
bcount = ((drive->media == ide_tape) ?
pc->req_xfer :
min(pc->req_xfer, 63 * 1024));
if (pc->flags & PC_FLAG_DMA_ERROR) {
pc->flags &= ~PC_FLAG_DMA_ERROR;
ide_dma_off(drive);
}
if (pc->flags & PC_FLAG_DMA_OK)
drive->dma = !ide_dma_prepare(drive, cmd);
if (!drive->dma)
pc->flags &= ~PC_FLAG_DMA_OK;
timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
: WAIT_TAPE_CMD;
}
ide_init_packet_cmd(cmd, valid_tf, bcount, drive->dma);
(void)do_rw_taskfile(drive, cmd);
if (drq_int) {
if (drive->dma)
drive->waiting_for_dma = 0;
hwif->expiry = expiry;
}
ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
return drq_int ? ide_started : ide_transfer_pc(drive);
}
EXPORT_SYMBOL_GPL(ide_issue_pc);