Re: [PATCH 06/15] drm/exynos/ipp: free partially allocated resources on error

From: Joonyoung Shim
Date: Wed Aug 27 2014 - 19:59:09 EST


Hi,

On 08/27/2014 07:27 PM, Andrzej Hajda wrote:
> On 08/26/2014 07:00 AM, Joonyoung Shim wrote:
>> Hi Andrzej,
>>
>> On 08/22/2014 04:52 PM, Andrzej Hajda wrote:
>>> In case of allocation errors some already allocated buffers
>>> were not freed. The patch fixes it.
>>>
>>> Signed-off-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
>>> ---
>>> drivers/gpu/drm/exynos/exynos_drm_ipp.c | 68 ++++++++++++++++-----------------
>>> 1 file changed, 33 insertions(+), 35 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_ipp.c b/drivers/gpu/drm/exynos/exynos_drm_ipp.c
>>> index 060a198..728f3b9 100644
>>> --- a/drivers/gpu/drm/exynos/exynos_drm_ipp.c
>>> +++ b/drivers/gpu/drm/exynos/exynos_drm_ipp.c
>>> @@ -599,6 +599,37 @@ static int ipp_set_mem_node(struct exynos_drm_ippdrv *ippdrv,
>>> return ret;
>>> }
>>>
>>> +static int ipp_put_mem_node(struct drm_device *drm_dev,
>>> + struct drm_exynos_ipp_cmd_node *c_node,
>>> + struct drm_exynos_ipp_mem_node *m_node)
>>> +{
>>> + int i;
>>> +
>>> + DRM_DEBUG_KMS("node[0x%x]\n", (int)m_node);
>>> +
>>> + if (!m_node) {
>>> + DRM_ERROR("invalid dequeue node.\n");
>>> + return -EFAULT;
>>> + }
>>> +
>>> + DRM_DEBUG_KMS("ops_id[%d]\n", m_node->ops_id);
>>> +
>>> + /* put gem buffer */
>>> + for_each_ipp_planar(i) {
>>> + unsigned long handle = m_node->buf_info.handles[i];
>>> + if (handle)
>>> + exynos_drm_gem_put_dma_addr(drm_dev, handle,
>>> + c_node->filp);
>>> + }
>>> +
>>> + /* conditionally remove from queue */
>>> + if (m_node->list.next)
>> How about do INIT_LIST_HEAD for list in ipp_get_mem_node()?
>
> I am not sure if it is better. For sure it adds unnecessary
> initialization sequence.

In other words, this NULL checking is unnecessary if you initialize the
list_head by INIT_LIST_HEAD.

> Maybe adding list_is_initialized inline function to list.h would be the
> best solution.

There is just list_empty and we can't know whether list is initialized
or not. I recommend to use initialized list_head.

Thanks.

>
> Regards
> Andrzej
>
>>
>>> + list_del(&m_node->list);
>>> + kfree(m_node);
>>> +
>>> + return 0;
>>> +}
>>> +
>>> static struct drm_exynos_ipp_mem_node
>>> *ipp_get_mem_node(struct drm_device *drm_dev,
>>> struct drm_file *file,
>>> @@ -634,7 +665,8 @@ static struct drm_exynos_ipp_mem_node
>>> qbuf->handle[i], file);
>>> if (IS_ERR(addr)) {
>>> DRM_ERROR("failed to get addr.\n");
>>> - goto err_clear;
>>> + ipp_put_mem_node(drm_dev, c_node, m_node);
>>> + return ERR_PTR(-EFAULT);
>>> }
>>>
>>> buf_info->handles[i] = qbuf->handle[i];
>>> @@ -649,40 +681,6 @@ static struct drm_exynos_ipp_mem_node
>>> mutex_unlock(&c_node->mem_lock);
>>>
>>> return m_node;
>>> -
>>> -err_clear:
>>> - kfree(m_node);
>>> - return ERR_PTR(-EFAULT);
>>> -}
>>> -
>>> -static int ipp_put_mem_node(struct drm_device *drm_dev,
>>> - struct drm_exynos_ipp_cmd_node *c_node,
>>> - struct drm_exynos_ipp_mem_node *m_node)
>>> -{
>>> - int i;
>>> -
>>> - DRM_DEBUG_KMS("node[0x%x]\n", (int)m_node);
>>> -
>>> - if (!m_node) {
>>> - DRM_ERROR("invalid dequeue node.\n");
>>> - return -EFAULT;
>>> - }
>>> -
>>> - DRM_DEBUG_KMS("ops_id[%d]\n", m_node->ops_id);
>>> -
>>> - /* put gem buffer */
>>> - for_each_ipp_planar(i) {
>>> - unsigned long handle = m_node->buf_info.handles[i];
>>> - if (handle)
>>> - exynos_drm_gem_put_dma_addr(drm_dev, handle,
>>> - c_node->filp);
>>> - }
>>> -
>>> - /* delete list in queue */
>>> - list_del(&m_node->list);
>>> - kfree(m_node);
>>> -
>>> - return 0;
>>> }
>>>
>>> static void ipp_free_event(struct drm_pending_event *event)
>>>
>>
>
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/