ide: fix races in handling of user-space SET XFER commands

* Make cmd->tf_flags field 'u16' and add IDE_TFLAG_SET_XFER taskfile flag.

* Update ide_finish_cmd() to set xfer / re-read id if the new flag is set.

* Convert set_xfer_rate() (write handler for /proc/ide/hd?/current_speed)
  and ide_cmd_ioctl() (HDIO_DRIVE_CMD ioctl handler) to use the new flag.

* Remove no longer needed disable_irq_nosync() + enable_irq() from
  ide_config_drive_speed().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Bartlomiej Zolnierkiewicz 2009-06-23 11:35:51 +00:00 committed by David S. Miller
parent fa56d4cb40
commit 665d66e8fa
5 changed files with 14 additions and 26 deletions

View File

@ -167,6 +167,8 @@ static int ide_cmd_ioctl(ide_drive_t *drive, unsigned long arg)
err = -EINVAL;
goto abort;
}
cmd.tf_flags |= IDE_TFLAG_SET_XFER;
}
err = ide_raw_taskfile(drive, &cmd, buf, args[3]);
@ -174,12 +176,6 @@ static int ide_cmd_ioctl(ide_drive_t *drive, unsigned long arg)
args[0] = tf->status;
args[1] = tf->error;
args[2] = tf->nsect;
if (!err && xfer_rate) {
/* active-retuning-calls future */
ide_set_xfer_rate(drive, xfer_rate);
ide_driveid_update(drive);
}
abort:
if (copy_to_user((void __user *)arg, &args, 4))
err = -EFAULT;

View File

@ -363,14 +363,6 @@ int ide_config_drive_speed(ide_drive_t *drive, u8 speed)
* this point (lost interrupt).
*/
/*
* FIXME: we race against the running IRQ here if
* this is called from non IRQ context. If we use
* disable_irq() we hang on the error path. Work
* is needed.
*/
disable_irq_nosync(hwif->irq);
udelay(1);
tp_ops->dev_select(drive);
SELECT_MASK(drive, 1);
@ -394,8 +386,6 @@ int ide_config_drive_speed(ide_drive_t *drive, u8 speed)
SELECT_MASK(drive, 0);
enable_irq(hwif->irq);
if (error) {
(void) ide_dump_status(drive, "set_drive_speed_status", stat);
return error;

View File

@ -195,7 +195,6 @@ ide_devset_get(xfer_rate, current_speed);
static int set_xfer_rate (ide_drive_t *drive, int arg)
{
struct ide_cmd cmd;
int err;
if (arg < XFER_PIO_0 || arg > XFER_UDMA_6)
return -EINVAL;
@ -206,14 +205,9 @@ static int set_xfer_rate (ide_drive_t *drive, int arg)
cmd.tf.nsect = (u8)arg;
cmd.valid.out.tf = IDE_VALID_FEATURE | IDE_VALID_NSECT;
cmd.valid.in.tf = IDE_VALID_NSECT;
cmd.tf_flags = IDE_TFLAG_SET_XFER;
err = ide_no_data_taskfile(drive, &cmd);
if (!err) {
ide_set_xfer_rate(drive, (u8) arg);
ide_driveid_update(drive);
}
return err;
return ide_no_data_taskfile(drive, &cmd);
}
ide_devset_rw(current_speed, xfer_rate);

View File

@ -324,10 +324,17 @@ static void ide_error_cmd(ide_drive_t *drive, struct ide_cmd *cmd)
void ide_finish_cmd(ide_drive_t *drive, struct ide_cmd *cmd, u8 stat)
{
struct request *rq = drive->hwif->rq;
u8 err = ide_read_error(drive);
u8 err = ide_read_error(drive), nsect = cmd->tf.nsect;
u8 set_xfer = !!(cmd->tf_flags & IDE_TFLAG_SET_XFER);
ide_complete_cmd(drive, cmd, stat, err);
rq->errors = err;
if (err == 0 && set_xfer) {
ide_set_xfer_rate(drive, nsect);
ide_driveid_update(drive);
}
ide_complete_rq(drive, err ? -EIO : 0, blk_rq_bytes(rq));
}

View File

@ -258,6 +258,7 @@ enum {
IDE_TFLAG_DYN = (1 << 5),
IDE_TFLAG_FS = (1 << 6),
IDE_TFLAG_MULTI_PIO = (1 << 7),
IDE_TFLAG_SET_XFER = (1 << 8),
};
enum {
@ -294,7 +295,7 @@ struct ide_cmd {
} out, in;
} valid;
u8 tf_flags;
u16 tf_flags;
u8 ftf_flags; /* for TASKFILE ioctl */
int protocol;