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>
diff --git a/drivers/ide/ide-ioctls.c b/drivers/ide/ide-ioctls.c
index e246d3d..d3440b5 100644
--- a/drivers/ide/ide-ioctls.c
+++ b/drivers/ide/ide-ioctls.c
@@ -167,6 +167,8 @@
err = -EINVAL;
goto abort;
}
+
+ cmd.tf_flags |= IDE_TFLAG_SET_XFER;
}
err = ide_raw_taskfile(drive, &cmd, buf, args[3]);
@@ -174,12 +176,6 @@
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;
diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c
index b998738..b14fa9a 100644
--- a/drivers/ide/ide-iops.c
+++ b/drivers/ide/ide-iops.c
@@ -363,14 +363,6 @@
* 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 @@
SELECT_MASK(drive, 0);
- enable_irq(hwif->irq);
-
if (error) {
(void) ide_dump_status(drive, "set_drive_speed_status", stat);
return error;
diff --git a/drivers/ide/ide-proc.c b/drivers/ide/ide-proc.c
index 3242698..021de41 100644
--- a/drivers/ide/ide-proc.c
+++ b/drivers/ide/ide-proc.c
@@ -195,7 +195,6 @@
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 @@
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);
diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c
index 50336d5..cc8633c 100644
--- a/drivers/ide/ide-taskfile.c
+++ b/drivers/ide/ide-taskfile.c
@@ -324,10 +324,17 @@
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));
}
diff --git a/include/linux/ide.h b/include/linux/ide.h
index cb6cd04..803c1ae 100644
--- a/include/linux/ide.h
+++ b/include/linux/ide.h
@@ -258,6 +258,7 @@
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 @@
} out, in;
} valid;
- u8 tf_flags;
+ u16 tf_flags;
u8 ftf_flags; /* for TASKFILE ioctl */
int protocol;