[PATCH] drm/vc4: remove all usages of of_node_put()

Amer Al Shanawany posted 1 patch 1 year, 7 months ago
drivers/gpu/drm/vc4/vc4_drv.c  | 14 ++++++--------
drivers/gpu/drm/vc4/vc4_hdmi.c |  4 +---
drivers/gpu/drm/vc4/vc4_hvs.c  |  4 +---
3 files changed, 8 insertions(+), 14 deletions(-)
[PATCH] drm/vc4: remove all usages of of_node_put()
Posted by Amer Al Shanawany 1 year, 7 months ago
Use the scope-based cleanup feature to clean up 'struct device_node *'
when they go out of scope, and remove all instances of of_node_put()
within the same scope, to simplify function exit and avoid potential
memory leaks.

Suggested-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Amer Al Shanawany <amer.shanawany@gmail.com>
---
 drivers/gpu/drm/vc4/vc4_drv.c  | 14 ++++++--------
 drivers/gpu/drm/vc4/vc4_hdmi.c |  4 +---
 drivers/gpu/drm/vc4/vc4_hvs.c  |  4 +---
 3 files changed, 8 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index c133e96b8aca..bb0bb052e595 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -289,7 +289,6 @@ static int vc4_drm_bind(struct device *dev)
 	struct rpi_firmware *firmware = NULL;
 	struct drm_device *drm;
 	struct vc4_dev *vc4;
-	struct device_node *node;
 	struct drm_crtc *crtc;
 	bool is_vc5;
 	int ret = 0;
@@ -302,11 +301,10 @@ static int vc4_drm_bind(struct device *dev)
 	else
 		driver = &vc4_drm_driver;
 
-	node = of_find_matching_node_and_match(NULL, vc4_dma_range_matches,
-					       NULL);
+	struct device_node *node __free(device_node) =
+		of_find_matching_node_and_match(NULL, vc4_dma_range_matches, NULL);
 	if (node) {
 		ret = of_dma_configure(dev, node, true);
-		of_node_put(node);
 
 		if (ret)
 			return ret;
@@ -341,10 +339,10 @@ static int vc4_drm_bind(struct device *dev)
 			goto err;
 	}
 
-	node = of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
-	if (node) {
-		firmware = rpi_firmware_get(node);
-		of_node_put(node);
+	struct device_node *np __free(device_node) =
+		of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
+	if (np) {
+		firmware = rpi_firmware_get(np);
 
 		if (!firmware) {
 			ret = -EPROBE_DEFER;
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index d30f8e8e8967..915e8da3f41a 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -3661,7 +3661,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
 	struct drm_device *drm = dev_get_drvdata(master);
 	struct vc4_hdmi *vc4_hdmi;
 	struct drm_encoder *encoder;
-	struct device_node *ddc_node;
 	int ret;
 
 	vc4_hdmi = drmm_kzalloc(drm, sizeof(*vc4_hdmi), GFP_KERNEL);
@@ -3699,14 +3698,13 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
 	if (ret)
 		return ret;
 
-	ddc_node = of_parse_phandle(dev->of_node, "ddc", 0);
+	struct device_node *ddc_node __free(device_node) = of_parse_phandle(dev->of_node, "ddc", 0);
 	if (!ddc_node) {
 		DRM_ERROR("Failed to find ddc node in device tree\n");
 		return -ENODEV;
 	}
 
 	vc4_hdmi->ddc = of_find_i2c_adapter_by_node(ddc_node);
-	of_node_put(ddc_node);
 	if (!vc4_hdmi->ddc) {
 		DRM_DEBUG("Failed to get ddc i2c adapter by node\n");
 		return -EPROBE_DEFER;
diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 04af672caacb..6e3613e06e09 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -845,15 +845,13 @@ static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
 
 	if (vc4->is_vc5) {
 		struct rpi_firmware *firmware;
-		struct device_node *node;
+		struct device_node *node __free(device_node) = rpi_firmware_find_node();
 		unsigned int max_rate;
 
-		node = rpi_firmware_find_node();
 		if (!node)
 			return -EINVAL;
 
 		firmware = rpi_firmware_get(node);
-		of_node_put(node);
 		if (!firmware)
 			return -EPROBE_DEFER;
 
-- 
2.34.1
Re: [PATCH] drm/vc4: remove all usages of of_node_put()
Posted by Amer Al Shanawany 1 year, 7 months ago
On 27/04/2024 15.40, Amer Al Shanawany wrote:
> Use the scope-based cleanup feature to clean up 'struct device_node *'
> when they go out of scope, and remove all instances of of_node_put()
> within the same scope, to simplify function exit and avoid potential
> memory leaks.
> 
> Suggested-by: Julia Lawall <julia.lawall@inria.fr>
> Signed-off-by: Amer Al Shanawany <amer.shanawany@gmail.com>
> ---
>   drivers/gpu/drm/vc4/vc4_drv.c  | 14 ++++++--------
>   drivers/gpu/drm/vc4/vc4_hdmi.c |  4 +---
>   drivers/gpu/drm/vc4/vc4_hvs.c  |  4 +---
>   3 files changed, 8 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
> index c133e96b8aca..bb0bb052e595 100644
> --- a/drivers/gpu/drm/vc4/vc4_drv.c
> +++ b/drivers/gpu/drm/vc4/vc4_drv.c
> @@ -289,7 +289,6 @@ static int vc4_drm_bind(struct device *dev)
>   	struct rpi_firmware *firmware = NULL;
>   	struct drm_device *drm;
>   	struct vc4_dev *vc4;
> -	struct device_node *node;
>   	struct drm_crtc *crtc;
>   	bool is_vc5;
>   	int ret = 0;
> @@ -302,11 +301,10 @@ static int vc4_drm_bind(struct device *dev)
>   	else
>   		driver = &vc4_drm_driver;
>   
> -	node = of_find_matching_node_and_match(NULL, vc4_dma_range_matches,
> -					       NULL);
> +	struct device_node *node __free(device_node) =
> +		of_find_matching_node_and_match(NULL, vc4_dma_range_matches, NULL);
>   	if (node) {
>   		ret = of_dma_configure(dev, node, true);
> -		of_node_put(node);
>   
>   		if (ret)
>   			return ret;
> @@ -341,10 +339,10 @@ static int vc4_drm_bind(struct device *dev)
>   			goto err;
>   	}
>   
> -	node = of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
> -	if (node) {
> -		firmware = rpi_firmware_get(node);
> -		of_node_put(node);
> +	struct device_node *np __free(device_node) =
> +		of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
> +	if (np) {
> +		firmware = rpi_firmware_get(np);
>   
>   		if (!firmware) {
>   			ret = -EPROBE_DEFER;
> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
> index d30f8e8e8967..915e8da3f41a 100644
> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
> @@ -3661,7 +3661,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
>   	struct drm_device *drm = dev_get_drvdata(master);
>   	struct vc4_hdmi *vc4_hdmi;
>   	struct drm_encoder *encoder;
> -	struct device_node *ddc_node;
>   	int ret;
>   
>   	vc4_hdmi = drmm_kzalloc(drm, sizeof(*vc4_hdmi), GFP_KERNEL);
> @@ -3699,14 +3698,13 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
>   	if (ret)
>   		return ret;
>   
> -	ddc_node = of_parse_phandle(dev->of_node, "ddc", 0);
> +	struct device_node *ddc_node __free(device_node) = of_parse_phandle(dev->of_node, "ddc", 0);
>   	if (!ddc_node) {
>   		DRM_ERROR("Failed to find ddc node in device tree\n");
>   		return -ENODEV;
>   	}
>   
>   	vc4_hdmi->ddc = of_find_i2c_adapter_by_node(ddc_node);
> -	of_node_put(ddc_node);
>   	if (!vc4_hdmi->ddc) {
>   		DRM_DEBUG("Failed to get ddc i2c adapter by node\n");
>   		return -EPROBE_DEFER;
> diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
> index 04af672caacb..6e3613e06e09 100644
> --- a/drivers/gpu/drm/vc4/vc4_hvs.c
> +++ b/drivers/gpu/drm/vc4/vc4_hvs.c
> @@ -845,15 +845,13 @@ static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
>   
>   	if (vc4->is_vc5) {
>   		struct rpi_firmware *firmware;
> -		struct device_node *node;
> +		struct device_node *node __free(device_node) = rpi_firmware_find_node();
>   		unsigned int max_rate;
>   
> -		node = rpi_firmware_find_node();
>   		if (!node)
>   			return -EINVAL;
>   
>   		firmware = rpi_firmware_get(node);
> -		of_node_put(node);
>   		if (!firmware)
>   			return -EPROBE_DEFER;
>   
Hi,

This patch is marked as new/archived on patchwork[1], however it didn't 
receive any feedback, and a similar patch has been already merged [2].


[1]: 
https://patchwork.kernel.org/project/dri-devel/patch/20240427134044.38910-1-amer.shanawany@gmail.com/

[2]: 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d65bfb9546eb627e3c578336355c5b81797f2255

Thank you

Amer
Re: [PATCH] drm/vc4: remove all usages of of_node_put()
Posted by Amer Al Shanawany 1 year, 6 months ago
On 5/22/24 16:48, Amer Al Shanawany wrote:
> On 27/04/2024 15.40, Amer Al Shanawany wrote:
>> Use the scope-based cleanup feature to clean up 'struct device_node *'
>> when they go out of scope, and remove all instances of of_node_put()
>> within the same scope, to simplify function exit and avoid potential
>> memory leaks.
>>
>> Suggested-by: Julia Lawall <julia.lawall@inria.fr>
>> Signed-off-by: Amer Al Shanawany <amer.shanawany@gmail.com>
>> ---
>>   drivers/gpu/drm/vc4/vc4_drv.c  | 14 ++++++--------
>>   drivers/gpu/drm/vc4/vc4_hdmi.c |  4 +---
>>   drivers/gpu/drm/vc4/vc4_hvs.c  |  4 +---
>>   3 files changed, 8 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
>> index c133e96b8aca..bb0bb052e595 100644
>> --- a/drivers/gpu/drm/vc4/vc4_drv.c
>> +++ b/drivers/gpu/drm/vc4/vc4_drv.c
>> @@ -289,7 +289,6 @@ static int vc4_drm_bind(struct device *dev)
>>       struct rpi_firmware *firmware = NULL;
>>       struct drm_device *drm;
>>       struct vc4_dev *vc4;
>> -    struct device_node *node;
>>       struct drm_crtc *crtc;
>>       bool is_vc5;
>>       int ret = 0;
>> @@ -302,11 +301,10 @@ static int vc4_drm_bind(struct device *dev)
>>       else
>>           driver = &vc4_drm_driver;
>>   -    node = of_find_matching_node_and_match(NULL, vc4_dma_range_matches,
>> -                           NULL);
>> +    struct device_node *node __free(device_node) =
>> +        of_find_matching_node_and_match(NULL, vc4_dma_range_matches, NULL);
>>       if (node) {
>>           ret = of_dma_configure(dev, node, true);
>> -        of_node_put(node);
>>             if (ret)
>>               return ret;
>> @@ -341,10 +339,10 @@ static int vc4_drm_bind(struct device *dev)
>>               goto err;
>>       }
>>   -    node = of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
>> -    if (node) {
>> -        firmware = rpi_firmware_get(node);
>> -        of_node_put(node);
>> +    struct device_node *np __free(device_node) =
>> +        of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
>> +    if (np) {
>> +        firmware = rpi_firmware_get(np);
>>             if (!firmware) {
>>               ret = -EPROBE_DEFER;
>> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
>> index d30f8e8e8967..915e8da3f41a 100644
>> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
>> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
>> @@ -3661,7 +3661,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
>>       struct drm_device *drm = dev_get_drvdata(master);
>>       struct vc4_hdmi *vc4_hdmi;
>>       struct drm_encoder *encoder;
>> -    struct device_node *ddc_node;
>>       int ret;
>>         vc4_hdmi = drmm_kzalloc(drm, sizeof(*vc4_hdmi), GFP_KERNEL);
>> @@ -3699,14 +3698,13 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
>>       if (ret)
>>           return ret;
>>   -    ddc_node = of_parse_phandle(dev->of_node, "ddc", 0);
>> +    struct device_node *ddc_node __free(device_node) = of_parse_phandle(dev->of_node, "ddc", 0);
>>       if (!ddc_node) {
>>           DRM_ERROR("Failed to find ddc node in device tree\n");
>>           return -ENODEV;
>>       }
>>         vc4_hdmi->ddc = of_find_i2c_adapter_by_node(ddc_node);
>> -    of_node_put(ddc_node);
>>       if (!vc4_hdmi->ddc) {
>>           DRM_DEBUG("Failed to get ddc i2c adapter by node\n");
>>           return -EPROBE_DEFER;
>> diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
>> index 04af672caacb..6e3613e06e09 100644
>> --- a/drivers/gpu/drm/vc4/vc4_hvs.c
>> +++ b/drivers/gpu/drm/vc4/vc4_hvs.c
>> @@ -845,15 +845,13 @@ static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
>>         if (vc4->is_vc5) {
>>           struct rpi_firmware *firmware;
>> -        struct device_node *node;
>> +        struct device_node *node __free(device_node) = rpi_firmware_find_node();
>>           unsigned int max_rate;
>>   -        node = rpi_firmware_find_node();
>>           if (!node)
>>               return -EINVAL;
>>             firmware = rpi_firmware_get(node);
>> -        of_node_put(node);
>>           if (!firmware)
>>               return -EPROBE_DEFER;
>>   
> Hi,
>
> This patch is marked as new/archived on patchwork[1], however it didn't receive any feedback, and a similar patch has been already merged [2].
>
>
> [1]: https://patchwork.kernel.org/project/dri-devel/patch/20240427134044.38910-1-amer.shanawany@gmail.com/
>
> [2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d65bfb9546eb627e3c578336355c5b81797f2255
>
> Thank you
>
> Amer
>
Hello,

Could anyone kindly provide some feedback on this patch?

Thank you

Amer
Re: [PATCH] drm/vc4: remove all usages of of_node_put()
Posted by Amer Al Shanawany 1 year, 5 months ago
On 18/06/2024 13.54, Amer Al Shanawany wrote:
> On 5/22/24 16:48, Amer Al Shanawany wrote:
>> On 27/04/2024 15.40, Amer Al Shanawany wrote:
>>> Use the scope-based cleanup feature to clean up 'struct device_node *'
>>> when they go out of scope, and remove all instances of of_node_put()
>>> within the same scope, to simplify function exit and avoid potential
>>> memory leaks.
>>>
>>> Suggested-by: Julia Lawall <julia.lawall@inria.fr>
>>> Signed-off-by: Amer Al Shanawany <amer.shanawany@gmail.com>
>>> ---
>>>    drivers/gpu/drm/vc4/vc4_drv.c  | 14 ++++++--------
>>>    drivers/gpu/drm/vc4/vc4_hdmi.c |  4 +---
>>>    drivers/gpu/drm/vc4/vc4_hvs.c  |  4 +---
>>>    3 files changed, 8 insertions(+), 14 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
>>> index c133e96b8aca..bb0bb052e595 100644
>>> --- a/drivers/gpu/drm/vc4/vc4_drv.c
>>> +++ b/drivers/gpu/drm/vc4/vc4_drv.c
>>> @@ -289,7 +289,6 @@ static int vc4_drm_bind(struct device *dev)
>>>        struct rpi_firmware *firmware = NULL;
>>>        struct drm_device *drm;
>>>        struct vc4_dev *vc4;
>>> -    struct device_node *node;
>>>        struct drm_crtc *crtc;
>>>        bool is_vc5;
>>>        int ret = 0;
>>> @@ -302,11 +301,10 @@ static int vc4_drm_bind(struct device *dev)
>>>        else
>>>            driver = &vc4_drm_driver;
>>>    -    node = of_find_matching_node_and_match(NULL, vc4_dma_range_matches,
>>> -                           NULL);
>>> +    struct device_node *node __free(device_node) =
>>> +        of_find_matching_node_and_match(NULL, vc4_dma_range_matches, NULL);
>>>        if (node) {
>>>            ret = of_dma_configure(dev, node, true);
>>> -        of_node_put(node);
>>>              if (ret)
>>>                return ret;
>>> @@ -341,10 +339,10 @@ static int vc4_drm_bind(struct device *dev)
>>>                goto err;
>>>        }
>>>    -    node = of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
>>> -    if (node) {
>>> -        firmware = rpi_firmware_get(node);
>>> -        of_node_put(node);
>>> +    struct device_node *np __free(device_node) =
>>> +        of_find_compatible_node(NULL, NULL, "raspberrypi,bcm2835-firmware");
>>> +    if (np) {
>>> +        firmware = rpi_firmware_get(np);
>>>              if (!firmware) {
>>>                ret = -EPROBE_DEFER;
>>> diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
>>> index d30f8e8e8967..915e8da3f41a 100644
>>> --- a/drivers/gpu/drm/vc4/vc4_hdmi.c
>>> +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
>>> @@ -3661,7 +3661,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
>>>        struct drm_device *drm = dev_get_drvdata(master);
>>>        struct vc4_hdmi *vc4_hdmi;
>>>        struct drm_encoder *encoder;
>>> -    struct device_node *ddc_node;
>>>        int ret;
>>>          vc4_hdmi = drmm_kzalloc(drm, sizeof(*vc4_hdmi), GFP_KERNEL);
>>> @@ -3699,14 +3698,13 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
>>>        if (ret)
>>>            return ret;
>>>    -    ddc_node = of_parse_phandle(dev->of_node, "ddc", 0);
>>> +    struct device_node *ddc_node __free(device_node) = of_parse_phandle(dev->of_node, "ddc", 0);
>>>        if (!ddc_node) {
>>>            DRM_ERROR("Failed to find ddc node in device tree\n");
>>>            return -ENODEV;
>>>        }
>>>          vc4_hdmi->ddc = of_find_i2c_adapter_by_node(ddc_node);
>>> -    of_node_put(ddc_node);
>>>        if (!vc4_hdmi->ddc) {
>>>            DRM_DEBUG("Failed to get ddc i2c adapter by node\n");
>>>            return -EPROBE_DEFER;
>>> diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
>>> index 04af672caacb..6e3613e06e09 100644
>>> --- a/drivers/gpu/drm/vc4/vc4_hvs.c
>>> +++ b/drivers/gpu/drm/vc4/vc4_hvs.c
>>> @@ -845,15 +845,13 @@ static int vc4_hvs_bind(struct device *dev, struct device *master, void *data)
>>>          if (vc4->is_vc5) {
>>>            struct rpi_firmware *firmware;
>>> -        struct device_node *node;
>>> +        struct device_node *node __free(device_node) = rpi_firmware_find_node();
>>>            unsigned int max_rate;
>>>    -        node = rpi_firmware_find_node();
>>>            if (!node)
>>>                return -EINVAL;
>>>              firmware = rpi_firmware_get(node);
>>> -        of_node_put(node);
>>>            if (!firmware)
>>>                return -EPROBE_DEFER;
>>>    
>> Hi,
>>
>> This patch is marked as new/archived on patchwork[1], however it didn't receive any feedback, and a similar patch has been already merged [2].
>>
>>
>> [1]: https://patchwork.kernel.org/project/dri-devel/patch/20240427134044.38910-1-amer.shanawany@gmail.com/
>>
>> [2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d65bfb9546eb627e3c578336355c5b81797f2255
>>
>> Thank you
>>
>> Amer
>>
> Hello,
> 
> Could anyone kindly provide some feedback on this patch?
> 
> Thank you
> 
> Amer
Hello all,

I have come to realize that unsubscribing from the mailing list shortly 
after sending this patch prevented me from receiving any feedback. My 
apologies for this oversight.

Thank you

Amer