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linux/drivers/ide/ide-atapi.c

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/*
* 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) {
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
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);
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
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;
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
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);
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
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);
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
int ide_queue_sense_rq(ide_drive_t *drive, void *special)
{
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
/* 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);
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
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);
ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo <tj@kernel.org>
2009-04-18 15:00:42 -07:00
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)) {
blkdev_dequeue_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;
}
block: add rq->resid_len rq->data_len served two purposes - the length of data buffer on issue and the residual count on completion. This duality creates some headaches. First of all, block layer and low level drivers can't really determine what rq->data_len contains while a request is executing. It could be the total request length or it coulde be anything else one of the lower layers is using to keep track of residual count. This complicates things because blk_rq_bytes() and thus [__]blk_end_request_all() relies on rq->data_len for PC commands. Drivers which want to report residual count should first cache the total request length, update rq->data_len and then complete the request with the cached data length. Secondly, it makes requests default to reporting full residual count, ie. reporting that no data transfer occurred. The residual count is an exception not the norm; however, the driver should clear rq->data_len to zero to signify the normal cases while leaving it alone means no data transfer occurred at all. This reverse default behavior complicates code unnecessarily and renders block PC on some drivers (ide-tape/floppy) unuseable. This patch adds rq->resid_len which is used only for residual count. While at it, remove now unnecessasry blk_rq_bytes() caching in ide_pc_intr() as rq->data_len is not changed anymore. Boaz : spotted missing conversion in osd Sergei : spotted too early conversion to blk_rq_bytes() in ide-tape [ Impact: cleanup residual count handling, report 0 resid by default ] Signed-off-by: Tejun Heo <tj@kernel.org> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Cc: Borislav Petkov <petkovbb@googlemail.com> Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com> Cc: Mike Miller <mike.miller@hp.com> Cc: Eric Moore <Eric.Moore@lsi.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: Mike Miller <mike.miller@hp.com> Cc: Eric Moore <Eric.Moore@lsi.com> Cc: Darrick J. Wong <djwong@us.ibm.com> Cc: Pete Zaitcev <zaitcev@redhat.com> Cc: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-07 06:24:37 -07:00
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);