V4L/DVB (10812): v4l2: Zero out read-only ioctls in one place
If an ioctl is read-only then the driver fills in all the fields. Lots of
times drivers only care about some fields so it's best if video_ioctl2
takes care of zeroing out the entire structure before handing it to the
driver. This saves code in each driver to do it and driver authors often
forget.
The existing memset code in some of the read-only ioctl handlers
can be deleted.
Convert a case statement to a single if statement.
Deleted a debug line from ENUMAUDOUT that was copy-and-pasted to G_AUDOUT
by mistake.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c
index 00c0f76..64b4fda 100644
--- a/drivers/media/video/v4l2-ioctl.c
+++ b/drivers/media/video/v4l2-ioctl.c
@@ -655,8 +655,6 @@
if (cmd == VIDIOCGMBUF) {
struct video_mbuf *p = arg;
- memset(p, 0, sizeof(*p));
-
if (!ops->vidiocgmbuf)
return ret;
ret = ops->vidiocgmbuf(file, fh, p);
@@ -683,7 +681,6 @@
case VIDIOC_QUERYCAP:
{
struct v4l2_capability *cap = (struct v4l2_capability *)arg;
- memset(cap, 0, sizeof(*cap));
if (!ops->vidioc_querycap)
break;
@@ -1367,7 +1364,6 @@
if (!ops->vidioc_g_audio)
break;
- memset(p, 0, sizeof(*p));
ret = ops->vidioc_g_audio(file, fh, p);
if (!ret)
dbgarg(cmd, "index=%d, name=%s, capability=0x%x, "
@@ -1409,7 +1405,7 @@
if (!ops->vidioc_g_audout)
break;
- dbgarg(cmd, "Enum for index=%d\n", p->index);
+
ret = ops->vidioc_g_audout(file, fh, p);
if (!ret)
dbgarg2("index=%d, name=%s, capability=%d, "
@@ -1506,8 +1502,6 @@
if (!ops->vidioc_g_jpegcomp)
break;
- memset(p, 0, sizeof(*p));
-
ret = ops->vidioc_g_jpegcomp(file, fh, p);
if (!ret)
dbgarg(cmd, "quality=%d, APPn=%d, "
@@ -1873,13 +1867,7 @@
cmd == VIDIOC_TRY_EXT_CTRLS);
/* Copy arguments into temp kernel buffer */
- switch (_IOC_DIR(cmd)) {
- case _IOC_NONE:
- parg = NULL;
- break;
- case _IOC_READ:
- case _IOC_WRITE:
- case (_IOC_WRITE | _IOC_READ):
+ if (_IOC_DIR(cmd) != _IOC_NONE) {
if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
parg = sbuf;
} else {
@@ -1900,8 +1888,10 @@
/* zero out anything we don't copy from userspace */
if (n < _IOC_SIZE(cmd))
memset((u8 *)parg + n, 0, _IOC_SIZE(cmd) - n);
+ } else {
+ /* read-only ioctl */
+ memset(parg, 0, _IOC_SIZE(cmd));
}
- break;
}
if (is_ext_ctrl) {
