Hi Sakari,
On Fri, Jan 15, 2021 at 11:56:21AM +0200, Sakari Ailus wrote:
> Hi Laurent,
>
> Thanks for the patch. It's a really nice improvement.
>
> On Thu, Jan 14, 2021 at 05:07:19AM +0200, Laurent Pinchart wrote:
> > The functions that add an async subdev to an async subdev notifier take
> > as an argument the size of the container structure they need to
> > allocate. This is error prone, as passing an invalid size will not be
> > caught by the compiler. Wrap those functions in macros that take a
> > container type instead of a size, and cast the returned pointer to the
> > desired type. The compiler will catch mistakes if the incorrect type is
> > passed to the macro, as the assignment types won't match.
> >
> > Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> > ---
> >
> > This patch is based on top of Ezequiel's "[PATCH 00/13] V4L2 Async
> > notifier API cleanup" series. It makes errors such as the one fixed by
> > "[PATCH] media: ti-vpe: cal: fix write to unallocated memory" impossible
> > to occur in the first place.
> >
> > drivers/media/i2c/max9286.c | 2 +-
> > drivers/media/i2c/st-mipid02.c | 2 +-
> > drivers/media/pci/intel/ipu3/ipu3-cio2.c | 10 ++---
> > drivers/media/platform/am437x/am437x-vpfe.c | 2 +-
> > drivers/media/platform/atmel/atmel-isi.c | 2 +-
> > .../media/platform/atmel/atmel-sama5d2-isc.c | 2 +-
> > drivers/media/platform/cadence/cdns-csi2rx.c | 3 +-
> > drivers/media/platform/davinci/vpif_capture.c | 2 +-
> > drivers/media/platform/exynos4-is/media-dev.c | 3 +-
> > .../media/platform/marvell-ccic/cafe-driver.c | 2 +-
> > .../media/platform/marvell-ccic/mmp-driver.c | 4 +-
> > drivers/media/platform/omap3isp/isp.c | 16 +++-----
> > drivers/media/platform/pxa_camera.c | 4 +-
> > drivers/media/platform/qcom/camss/camss.c | 11 ++----
> > drivers/media/platform/rcar-vin/rcar-core.c | 5 ++-
> > drivers/media/platform/rcar-vin/rcar-csi2.c | 2 +-
> > drivers/media/platform/rcar_drif.c | 2 +-
> > drivers/media/platform/renesas-ceu.c | 20 ++++------
> > .../platform/rockchip/rkisp1/rkisp1-dev.c | 10 ++---
> > drivers/media/platform/stm32/stm32-dcmi.c | 3 +-
> > .../platform/sunxi/sun4i-csi/sun4i_csi.c | 4 +-
> > drivers/media/platform/ti-vpe/cal.c | 12 +++---
> > drivers/media/platform/video-mux.c | 2 +-
> > drivers/media/platform/xilinx/xilinx-vipp.c | 10 ++---
> > drivers/media/v4l2-core/v4l2-async.c | 38 +++++++++----------
> > drivers/media/v4l2-core/v4l2-fwnode.c | 4 +-
> > drivers/staging/media/imx/imx-media-csi.c | 2 +-
> > drivers/staging/media/imx/imx-media-of.c | 2 +-
> > drivers/staging/media/imx/imx6-mipi-csi2.c | 2 +-
> > drivers/staging/media/imx/imx7-media-csi.c | 2 +-
> > drivers/staging/media/imx/imx7-mipi-csis.c | 2 +-
> > drivers/staging/media/tegra-video/vi.c | 10 ++---
> > include/media/v4l2-async.h | 36 ++++++++++++------
> > 33 files changed, 116 insertions(+), 117 deletions(-)
> >
> > diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c
> > index c82c1493e099..c31858548d34 100644
> > --- a/drivers/media/i2c/max9286.c
> > +++ b/drivers/media/i2c/max9286.c
> > @@ -580,7 +580,7 @@ static int max9286_v4l2_notifier_register(struct max9286_priv *priv)
> >
> > asd = v4l2_async_notifier_add_fwnode_subdev(&priv->notifier,
> > source->fwnode,
> > - sizeof(*asd));
> > + struct v4l2_async_subdev);
>
> Would it be possible to use *asd here instead?
Is that really better ? I mean, we could add even more shortcuts by
defining the macro as
#define v4l2_async_notifier_add_fwnode_remote_subdev(__notifier, __ep, __var) \
__var = (typeof(var)__v4l2_async_notifier_add_fwnode_remote_subdev(__notifier, __ep, \
sizeof(*__var)))
and using it as
v4l2_async_notifier_add_fwnode_subdev(&priv->notifier,
source->fwnode, asd);
but at some point it becomes confusing. Passing a struct type to a macro
is a fairly well established practice in the kernel, I think it would be
best to stick to it.
> You'd need typeof(), too.
>
> Same for the rest.
--
Regards,
Laurent Pinchart
