Re: [RFCv4 PATCH 08/11] vb2: q->num_buffers was updated too soon

2014-02-23 Thread Hans Verkuil
On 02/14/2014 11:41 AM, Hans Verkuil wrote:
> From: Hans Verkuil 
> 
> In __reqbufs() and __create_bufs() the q->num_buffers field was updated
> with the number of newly allocated buffers, but right after that those are
> freed again if some error had occurred before. Move the line updating
> num_buffers to *after* that error check.
> 
> Signed-off-by: Hans Verkuil 

NACK: this is actually correct behavior since __vb2_queue_free() subtracts
'allocated_buffers' from q->num_buffers. A comment mentioning this might be
useful, though.

Regards,

Hans

> ---
>  drivers/media/v4l2-core/videobuf2-core.c | 8 
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/media/v4l2-core/videobuf2-core.c 
> b/drivers/media/v4l2-core/videobuf2-core.c
> index ad3db83..96c5ac6 100644
> --- a/drivers/media/v4l2-core/videobuf2-core.c
> +++ b/drivers/media/v4l2-core/videobuf2-core.c
> @@ -848,13 +848,13 @@ static int __reqbufs(struct vb2_queue *q, struct 
> v4l2_requestbuffers *req)
>*/
>   }
>  
> - q->num_buffers = allocated_buffers;
> -
>   if (ret < 0) {
>   __vb2_queue_free(q, allocated_buffers);
>   return ret;
>   }
>  
> + q->num_buffers = allocated_buffers;
> +
>   /*
>* Return the number of successfully allocated buffers
>* to the userspace.
> @@ -957,13 +957,13 @@ static int __create_bufs(struct vb2_queue *q, struct 
> v4l2_create_buffers *create
>*/
>   }
>  
> - q->num_buffers += allocated_buffers;
> -
>   if (ret < 0) {
>   __vb2_queue_free(q, allocated_buffers);
>   return -ENOMEM;
>   }
>  
> + q->num_buffers += allocated_buffers;
> +
>   /*
>* Return the number of successfully allocated buffers
>* to the userspace.
> 

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[RFCv4 PATCH 08/11] vb2: q->num_buffers was updated too soon

2014-02-14 Thread Hans Verkuil
From: Hans Verkuil 

In __reqbufs() and __create_bufs() the q->num_buffers field was updated
with the number of newly allocated buffers, but right after that those are
freed again if some error had occurred before. Move the line updating
num_buffers to *after* that error check.

Signed-off-by: Hans Verkuil 
---
 drivers/media/v4l2-core/videobuf2-core.c | 8 
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/media/v4l2-core/videobuf2-core.c 
b/drivers/media/v4l2-core/videobuf2-core.c
index ad3db83..96c5ac6 100644
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -848,13 +848,13 @@ static int __reqbufs(struct vb2_queue *q, struct 
v4l2_requestbuffers *req)
 */
}
 
-   q->num_buffers = allocated_buffers;
-
if (ret < 0) {
__vb2_queue_free(q, allocated_buffers);
return ret;
}
 
+   q->num_buffers = allocated_buffers;
+
/*
 * Return the number of successfully allocated buffers
 * to the userspace.
@@ -957,13 +957,13 @@ static int __create_bufs(struct vb2_queue *q, struct 
v4l2_create_buffers *create
 */
}
 
-   q->num_buffers += allocated_buffers;
-
if (ret < 0) {
__vb2_queue_free(q, allocated_buffers);
return -ENOMEM;
}
 
+   q->num_buffers += allocated_buffers;
+
/*
 * Return the number of successfully allocated buffers
 * to the userspace.
-- 
1.8.4.rc3

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