Switch to resource-managed function devm_kzalloc instead
of kzolloc and remove unneeded kzfree
Also, remove kzfree in probe function and remove
function,vpfe_remove as it is now has nothing to do.
The Coccinelle semantic patch used to make this change is as follows:
/<smpl>
@platform@
identifier p, probefn, removefn;
@@
struct platform_driver p = {
.probe = probefn,
.remove = removefn,
};
@prb@
identifier platform.probefn, pdev;
expression e, e1, e2;
@@
probefn(struct platform_device *pdev, ...) {
<+...
- e = kzalloc(e1, e2)
+ e = devm_kzalloc(&pdev->dev, e1, e2)
...
?-kzfree(e);
...+>
}
@rem depends on prb@
identifier platform.removefn;
expression prb.e;
@@
removefn(...) {
<...
- kzfree(e);
...>
}
//</smpl>
Signed-off-by: Nadim Almas <[email protected]>
---
drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c b/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
index bf077f8..cd44f0f 100644
--- a/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
+++ b/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
@@ -579,7 +579,7 @@ static int vpfe_probe(struct platform_device *pdev)
struct resource *res1;
int ret = -ENOMEM;
- vpfe_dev = kzalloc(sizeof(*vpfe_dev), GFP_KERNEL);
+ vpfe_dev = devm_kzalloc(&pdev->dev, sizeof(*vpfe_dev), GFP_KERNEL);
if (!vpfe_dev)
return ret;
@@ -681,7 +681,6 @@ static int vpfe_probe(struct platform_device *pdev)
probe_disable_clock:
vpfe_disable_clock(vpfe_dev);
probe_free_dev_mem:
- kzfree(vpfe_dev);
return ret;
}
@@ -702,7 +701,6 @@ static int vpfe_remove(struct platform_device *pdev)
v4l2_device_unregister(&vpfe_dev->v4l2_dev);
media_device_unregister(&vpfe_dev->media_dev);
vpfe_disable_clock(vpfe_dev);
- kzfree(vpfe_dev);
return 0;
}
--
2.7.4
On Wed, 2 Nov 2016, Nadim Almas wrote:
> Switch to resource-managed function devm_kzalloc instead
> of kzolloc and remove unneeded kzfree
>
> Also, remove kzfree in probe function and remove
> function,vpfe_remove as it is now has nothing to do.
> The Coccinelle semantic patch used to make this change is as follows:
> /<smpl>
> @platform@
> identifier p, probefn, removefn;
> @@
> struct platform_driver p = {
> .probe = probefn,
> .remove = removefn,
> };
>
> @prb@
> identifier platform.probefn, pdev;
> expression e, e1, e2;
> @@
> probefn(struct platform_device *pdev, ...) {
> <+...
> - e = kzalloc(e1, e2)
> + e = devm_kzalloc(&pdev->dev, e1, e2)
> ...
> ?-kzfree(e);
> ...+>
> }
> @rem depends on prb@
> identifier platform.removefn;
> expression prb.e;
> @@
> removefn(...) {
> <...
> - kzfree(e);
> ...>
> }
> //</smpl>
>
> Signed-off-by: Nadim Almas <[email protected]>
> ---
> drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c b/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
> index bf077f8..cd44f0f 100644
> --- a/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
> +++ b/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
> @@ -579,7 +579,7 @@ static int vpfe_probe(struct platform_device *pdev)
> struct resource *res1;
> int ret = -ENOMEM;
>
> - vpfe_dev = kzalloc(sizeof(*vpfe_dev), GFP_KERNEL);
> + vpfe_dev = devm_kzalloc(&pdev->dev, sizeof(*vpfe_dev), GFP_KERNEL);
> if (!vpfe_dev)
> return ret;
>
> @@ -681,7 +681,6 @@ static int vpfe_probe(struct platform_device *pdev)
> probe_disable_clock:
> vpfe_disable_clock(vpfe_dev);
> probe_free_dev_mem:
> - kzfree(vpfe_dev);
Kzfree zeroes the data before freeing it. Devm_kzalloc only causes a
kfree to happen, not a kzfree. If the kzfree is needed, then a memset 0
would need to replace the calls to kzfree.
There are some other minor issues with the patch. In the subject line,
there is normally a space after each :. There is a spelling mistake in
the commit message. In the commit message there should be one space
betwee words within a sentence, and there should be a space after a comma,
or other puctuation.
julia
>
> return ret;
> }
> @@ -702,7 +701,6 @@ static int vpfe_remove(struct platform_device *pdev)
> v4l2_device_unregister(&vpfe_dev->v4l2_dev);
> media_device_unregister(&vpfe_dev->media_dev);
> vpfe_disable_clock(vpfe_dev);
> - kzfree(vpfe_dev);
>
> return 0;
> }
> --
> 2.7.4
>
>
Hi Julia,
On Wednesday 02 Nov 2016 07:24:29 Julia Lawall wrote:
> On Wed, 2 Nov 2016, Nadim Almas wrote:
> > Switch to resource-managed function devm_kzalloc instead
> > of kzolloc and remove unneeded kzfree
> >
> > Also, remove kzfree in probe function and remove
> > function,vpfe_remove as it is now has nothing to do.
> > The Coccinelle semantic patch used to make this change is as follows:
> > /<smpl>
> > @platform@
> > identifier p, probefn, removefn;
> > @@
> > struct platform_driver p = {
> > .probe = probefn,
> > .remove = removefn,
> > };
> >
> > @prb@
> > identifier platform.probefn, pdev;
> > expression e, e1, e2;
> > @@
> > probefn(struct platform_device *pdev, ...) {
> > <+...
> > - e = kzalloc(e1, e2)
> > + e = devm_kzalloc(&pdev->dev, e1, e2)
> > ...
> > ?-kzfree(e);
> > ...+>
> > }
> > @rem depends on prb@
> > identifier platform.removefn;
> > expression prb.e;
> > @@
> > removefn(...) {
> > <...
> > - kzfree(e);
> > ...>
> > }
> > //</smpl>
> >
> > Signed-off-by: Nadim Almas <[email protected]>
> > ---
> >
> > drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c | 4 +---
> > 1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
> > b/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c index
> > bf077f8..cd44f0f 100644
> > --- a/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
> > +++ b/drivers/staging/media/davinci_vpfe/vpfe_mc_capture.c
> > @@ -579,7 +579,7 @@ static int vpfe_probe(struct platform_device *pdev)
> > struct resource *res1;
> > int ret = -ENOMEM;
> >
> > - vpfe_dev = kzalloc(sizeof(*vpfe_dev), GFP_KERNEL);
> > + vpfe_dev = devm_kzalloc(&pdev->dev, sizeof(*vpfe_dev), GFP_KERNEL);
> > if (!vpfe_dev)
> > return ret;
> >
> > @@ -681,7 +681,6 @@ static int vpfe_probe(struct platform_device *pdev)
> > probe_disable_clock:
> > vpfe_disable_clock(vpfe_dev);
> > probe_free_dev_mem:
> > - kzfree(vpfe_dev);
>
> Kzfree zeroes the data before freeing it. Devm_kzalloc only causes a
> kfree to happen, not a kzfree. If the kzfree is needed, then a memset 0
> would need to replace the calls to kzfree.
I don't think kzfree() is needed in this case.
> There are some other minor issues with the patch. In the subject line,
> there is normally a space after each :. There is a spelling mistake in
> the commit message. In the commit message there should be one space
> betwee words within a sentence, and there should be a space after a comma,
> or other puctuation.
Beside, I don't think devm_kzalloc() is a good idea. The vpfe_device structure
embeds data accessible from userspace through ioctls, and thus potentially
needs to survive unbinding the driver from the device. This isn't currently
implemented now, but devm_kzalloc() just goes in the wrong direction.
> > return ret;
> > }
> >
> > @@ -702,7 +701,6 @@ static int vpfe_remove(struct platform_device *pdev)
> > v4l2_device_unregister(&vpfe_dev->v4l2_dev);
> > media_device_unregister(&vpfe_dev->media_dev);
> > vpfe_disable_clock(vpfe_dev);
> > - kzfree(vpfe_dev);
> > return 0;
> > }
> >
--
Regards,
Laurent Pinchart