Re: [PATCH v5 5/7] udmabuf: introduce udmabuf init and deinit helper

[Huan Yang]

在 2024/9/6 16:20, Kasireddy, Vivek 写道:
> Hi Huan,
>
> > Subject: [PATCH v5 5/7] udmabuf: introduce udmabuf init and deinit helper
> >
> > After udmabuf is allocated, its resources need to be initialized,
> > including various array structures. The current array structure has
> > already been greatly expanded.
> >
> > Also, before udmabuf needs to be kfree, the occupied resources need to
> > be released.
> >
> > This part is repetitive and maybe overlooked.
> >
> > This patch give a helper function when init and deinit, by this,
> > deduce duplicate code.
> *reduce
>
> If possible, please try to improve the wording and grammatical correctness
> in the commit messages of other patches as well.

I'll fix it in next-version

> > Signed-off-by: Huan Yang <link@xxxxxxxx>
> > ---
> >   drivers/dma-buf/udmabuf.c | 52 +++++++++++++++++++++++----------------
> >   1 file changed, 31 insertions(+), 21 deletions(-)
> >
> > diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
> > index ca2b21c5c57f..254d9ec3d9f3 100644
> > --- a/drivers/dma-buf/udmabuf.c
> > +++ b/drivers/dma-buf/udmabuf.c
> > @@ -226,6 +226,28 @@ static int add_to_unpin_list(struct list_head
> > *unpin_list,
> >   	return 0;
> >   }
> >
> > +static __always_inline int init_udmabuf(struct udmabuf *ubuf, pgoff_t
> > pgcnt)
> > +{
> > +	INIT_LIST_HEAD(&ubuf->unpin_list);
> > +
> > +	ubuf->folios = kvmalloc_array(pgcnt, sizeof(*ubuf->folios),
> > GFP_KERNEL);
> > +	if (!ubuf->folios)
> > +		return -ENOMEM;
> > +
> > +	ubuf->offsets = kvcalloc(pgcnt, sizeof(*ubuf->offsets), GFP_KERNEL);
> > +	if (!ubuf->offsets)
> > +		return -ENOMEM;
> > +
> > +	return 0;
> > +}
> > +
> > +static __always_inline void deinit_udmabuf(struct udmabuf *ubuf)
> > +{
> > +	unpin_all_folios(&ubuf->unpin_list);
> > +	kvfree(ubuf->offsets);
> > +	kvfree(ubuf->folios);
> > +}
> > +
> >   static void release_udmabuf(struct dma_buf *buf)
> >   {
> >   	struct udmabuf *ubuf = buf->priv;
> > @@ -234,9 +256,7 @@ static void release_udmabuf(struct dma_buf *buf)
> >   	if (ubuf->sg)
> >   		put_sg_table(dev, ubuf->sg, DMA_BIDIRECTIONAL);
> >
> > -	unpin_all_folios(&ubuf->unpin_list);
> > -	kvfree(ubuf->offsets);
> > -	kvfree(ubuf->folios);
> > +	deinit_udmabuf(ubuf);
> >   	kfree(ubuf);
> >   }
> >
> > @@ -396,33 +416,24 @@ static long udmabuf_create(struct miscdevice
> > *device,
> >   	if (!ubuf)
> >   		return -ENOMEM;
> >
> > -	INIT_LIST_HEAD(&ubuf->unpin_list);
> >   	pglimit = (size_limit_mb * 1024 * 1024) >> PAGE_SHIFT;
> >   	for (i = 0; i < head->count; i++) {
> >   		if (!PAGE_ALIGNED(list[i].offset))
> > -			goto err;
> > +			goto err_noinit;
> >   		if (!PAGE_ALIGNED(list[i].size))
> > -			goto err;
> > +			goto err_noinit;
> >
> >   		pgcnt += list[i].size >> PAGE_SHIFT;
> >   		if (pgcnt > pglimit)
> > -			goto err;
> > +			goto err_noinit;
> >   	}
> >
> >   	if (!pgcnt)
> > -		goto err;
> > +		goto err_noinit;
> >
> > -	ubuf->folios = kvmalloc_array(pgcnt, sizeof(*ubuf->folios),
> > GFP_KERNEL);
> > -	if (!ubuf->folios) {
> > -		ret = -ENOMEM;
> > +	ret = init_udmabuf(ubuf, pgcnt);
> > +	if (ret)
> >   		goto err;
> > -	}
> > -
> > -	ubuf->offsets = kvcalloc(pgcnt, sizeof(*ubuf->offsets), GFP_KERNEL);
> > -	if (!ubuf->offsets) {
> > -		ret = -ENOMEM;
> > -		goto err;
> > -	}
> >
> >   	for (i = 0; i < head->count; i++) {
> >   		struct file *memfd = fget(list[i].memfd);
> > @@ -446,9 +457,8 @@ static long udmabuf_create(struct miscdevice
> > *device,
> >   	return ret;
> >
> >   err:
> > -	unpin_all_folios(&ubuf->unpin_list);
> > -	kvfree(ubuf->offsets);
> > -	kvfree(ubuf->folios);
> > +	deinit_udmabuf(ubuf);
> > +err_noinit:
> I don't really see the need for this new label, but I guess it makes things a
> bit clear.

If not this, each list err will need kfree, I think use this more clear.

Thank you. :)

> Acked-by: Vivek Kasireddy <vivek.kasireddy@xxxxxxxxx>
>
> >   	kfree(ubuf);
> >   	return ret;
> >   }
> > --
> > 2.45.2