From: Alan Cox <[EMAIL PROTECTED]>
Another step to removing ->ioctl and to removing the BKL
Signed-off-by: Alan Cox <[EMAIL PROTECTED]>
[ [EMAIL PROTECTED] -- take final step; BKL not needed ]
Signed-off-by: David Brownell <[EMAIL PROTECTED]>
---
Goes on top of the two patches addressing oopsing in "rmmod spi_master".
drivers/spi/spidev.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
--- a/drivers/spi/spidev.c 2008-05-22 13:40:36.000000000 -0700
+++ b/drivers/spi/spidev.c 2008-05-22 18:33:51.000000000 -0700
@@ -229,7 +229,6 @@ static int spidev_message(struct spidev_
* We walk the array of user-provided transfers, using each one
* to initialize a kernel version of the same transfer.
*/
- mutex_lock(&spidev->buf_lock);
buf = spidev->buffer;
total = 0;
for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers;
@@ -297,14 +296,12 @@ static int spidev_message(struct spidev_
status = total;
done:
- mutex_unlock(&spidev->buf_lock);
kfree(k_xfers);
return status;
}
-static int
-spidev_ioctl(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
+static long
+spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
int err = 0;
int retval = 0;
@@ -342,6 +339,14 @@ spidev_ioctl(struct inode *inode, struct
if (spi == NULL)
return -ESHUTDOWN;
+ /* use the buffer lock here for triple duty:
+ * - prevent I/O (from us) so calling spi_setup() is safe;
+ * - prevent concurrent SPI_IOC_WR_* from morphing
+ * data fields while SPI_IOC_RD_* reads them;
+ * - SPI_IOC_MESSAGE needs the buffer locked "normally".
+ */
+ mutex_lock(&spidev->buf_lock);
+
switch (cmd) {
/* read requests */
case SPI_IOC_RD_MODE:
@@ -457,6 +462,8 @@ spidev_ioctl(struct inode *inode, struct
kfree(ioc);
break;
}
+
+ mutex_unlock(&spidev->buf_lock);
spi_dev_put(spi);
return retval;
}
@@ -532,7 +539,7 @@ static struct file_operations spidev_fop
*/
.write = spidev_write,
.read = spidev_read,
- .ioctl = spidev_ioctl,
+ .unlocked_ioctl = spidev_ioctl,
.open = spidev_open,
.release = spidev_release,
};
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