From 337f9d205972bfe1cb7982384fd0f4caa4af001d Mon Sep 17 00:00:00 2001 From: Trent Piepho Date: Wed, 4 Mar 2009 01:21:02 -0300 Subject: [PATCH] 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 Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/v4l2-ioctl.c | 20 +++++--------------- 1 file changed, 5 insertions(+), 15 deletions(-) diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c index 00c0f76b9b5d..64b4fda08dd5 100644 --- a/drivers/media/video/v4l2-ioctl.c +++ b/drivers/media/video/v4l2-ioctl.c @@ -655,8 +655,6 @@ static long __video_do_ioctl(struct file *file, 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 @@ static long __video_do_ioctl(struct file *file, 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 @@ static long __video_do_ioctl(struct file *file, 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 @@ static long __video_do_ioctl(struct file *file, 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 @@ static long __video_do_ioctl(struct file *file, 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 @@ long video_ioctl2(struct file *file, 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 @@ long video_ioctl2(struct file *file, /* 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) { -- 2.30.2