2011-05-13 16:46:18

by Julia Lawall

Subject: [PATCH] arch/arm/mach-omap1/dma.c: Invert calls to platform_device_put and platform_device_del

From: Julia Lawall <[email protected]>

Platform_device_del should be called before platform_device_put, as
platform_device_put can delete the structure.

Additionally, improve the error handling code for the call to ioremap, so
that it calls platform_device_put.

The semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e1,e2;
@@

*platform_device_put(e1);
... when != e1 = e2
*platform_device_del(e1);
// </smpl>

Signed-off-by: Julia Lawall <[email protected]>

---
Is an ioremap needed also? Not clear, because dma_base i a global variable.

arch/arm/mach-omap1/dma.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-omap1/dma.c b/arch/arm/mach-omap1/dma.c
index d855934..f5a5220 100644
--- a/arch/arm/mach-omap1/dma.c
+++ b/arch/arm/mach-omap1/dma.c
@@ -284,14 +284,15 @@ static int __init omap1_system_dma_init(void)
dma_base = ioremap(res[0].start, resource_size(&res[0]));
if (!dma_base) {
pr_err("%s: Unable to ioremap\n", __func__);
- return -ENODEV;
+ ret = -ENODEV;
+ goto exit_device_put;
}

ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
if (ret) {
dev_err(&pdev->dev, "%s: Unable to add resources for %s%d\n",
__func__, pdev->name, pdev->id);
- goto exit_device_del;
+ goto exit_device_put;
}

p = kzalloc(sizeof(struct omap_system_dma_plat_info), GFP_KERNEL);
@@ -299,7 +300,7 @@ static int __init omap1_system_dma_init(void)
dev_err(&pdev->dev, "%s: Unable to allocate 'p' for %s\n",
__func__, pdev->name);
ret = -ENOMEM;
- goto exit_device_put;
+ goto exit_device_del;
}

d = kzalloc(sizeof(struct omap_dma_dev_attr), GFP_KERNEL);
@@ -380,10 +381,10 @@ exit_release_d:
kfree(d);
exit_release_p:
kfree(p);
-exit_device_put:
- platform_device_put(pdev);
exit_device_del:
platform_device_del(pdev);
+exit_device_put:
+ platform_device_put(pdev);

return ret;
}

2011-05-31 07:40:59

by Tony Lindgren

Subject: Re: [PATCH] arch/arm/mach-omap1/dma.c: Invert calls to platform_device_put and platform_device_del

* Julia Lawall <[email protected]> [110513 09:42]:
> From: Julia Lawall <[email protected]>
>
> Platform_device_del should be called before platform_device_put, as
> platform_device_put can delete the structure.
>
> Additionally, improve the error handling code for the call to ioremap, so
> that it calls platform_device_put.
>
> The semantic match that finds this problem is:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @@
> expression e1,e2;
> @@
>
> *platform_device_put(e1);
> ... when != e1 = e2
> *platform_device_del(e1);
> // </smpl>
>
> Signed-off-by: Julia Lawall <[email protected]>

Thanks, applying into fixes.

>
> ---
> Is an ioremap needed also? Not clear, because dma_base i a global variable.

I guess you mean iounmap instead of ioremap? In this case we have static
mappings for ioremap, so iounmap is not doing anything. But should be done
for correct handling.

Regards,

Tony

> arch/arm/mach-omap1/dma.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/arch/arm/mach-omap1/dma.c b/arch/arm/mach-omap1/dma.c
> index d855934..f5a5220 100644
> --- a/arch/arm/mach-omap1/dma.c
> +++ b/arch/arm/mach-omap1/dma.c
> @@ -284,14 +284,15 @@ static int __init omap1_system_dma_init(void)
> dma_base = ioremap(res[0].start, resource_size(&res[0]));
> if (!dma_base) {
> pr_err("%s: Unable to ioremap\n", __func__);
> - return -ENODEV;
> + ret = -ENODEV;
> + goto exit_device_put;
> }
>
> ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
> if (ret) {
> dev_err(&pdev->dev, "%s: Unable to add resources for %s%d\n",
> __func__, pdev->name, pdev->id);
> - goto exit_device_del;
> + goto exit_device_put;
> }
>
> p = kzalloc(sizeof(struct omap_system_dma_plat_info), GFP_KERNEL);
> @@ -299,7 +300,7 @@ static int __init omap1_system_dma_init(void)
> dev_err(&pdev->dev, "%s: Unable to allocate 'p' for %s\n",
> __func__, pdev->name);
> ret = -ENOMEM;
> - goto exit_device_put;
> + goto exit_device_del;
> }
>
> d = kzalloc(sizeof(struct omap_dma_dev_attr), GFP_KERNEL);
> @@ -380,10 +381,10 @@ exit_release_d:
> kfree(d);
> exit_release_p:
> kfree(p);
> -exit_device_put:
> - platform_device_put(pdev);
> exit_device_del:
> platform_device_del(pdev);
> +exit_device_put:
> + platform_device_put(pdev);
>
> return ret;
> }
>