From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mailout4.w1.samsung.com ([210.118.77.14]:14329 "EHLO mailout4.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756007Ab2FNNiM (ORCPT ); Thu, 14 Jun 2012 09:38:12 -0400 Received: from euspt2 (mailout4.w1.samsung.com [210.118.77.14]) by mailout4.w1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0M5M005NJ0KR2N60@mailout4.w1.samsung.com> for linux-media@vger.kernel.org; Thu, 14 Jun 2012 14:38:51 +0100 (BST) Received: from linux.samsung.com ([106.116.38.10]) by spt2.w1.samsung.com (iPlanet Messaging Server 5.2 Patch 2 (built Jul 14 2004)) with ESMTPA id <0M5M00C110JJHO@spt2.w1.samsung.com> for linux-media@vger.kernel.org; Thu, 14 Jun 2012 14:38:08 +0100 (BST) Date: Thu, 14 Jun 2012 15:37:40 +0200 From: Tomasz Stanislawski Subject: [PATCHv7 06/15] v4l: vb2-dma-contig: remove reference of alloc_ctx from a buffer In-reply-to: <1339681069-8483-1-git-send-email-t.stanislaws@samsung.com> To: linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org Cc: airlied@redhat.com, m.szyprowski@samsung.com, t.stanislaws@samsung.com, kyungmin.park@samsung.com, laurent.pinchart@ideasonboard.com, sumit.semwal@ti.com, daeinki@gmail.com, daniel.vetter@ffwll.ch, robdclark@gmail.com, pawel@osciak.com, linaro-mm-sig@lists.linaro.org, hverkuil@xs4all.nl, remi@remlab.net, subashrp@gmail.com, mchehab@redhat.com, g.liakhovetski@gmx.de Message-id: <1339681069-8483-7-git-send-email-t.stanislaws@samsung.com> Content-transfer-encoding: 7BIT References: <1339681069-8483-1-git-send-email-t.stanislaws@samsung.com> Sender: linux-media-owner@vger.kernel.org List-ID: This patch removes a reference to alloc_ctx from an instance of a DMA contiguous buffer. It helps to avoid a risk of a dangling pointer if the context is released while the buffer is still valid. Moreover it removes one dereference step while accessing a device structure. Signed-off-by: Tomasz Stanislawski Signed-off-by: Kyungmin Park --- drivers/media/video/videobuf2-dma-contig.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index a05784f..20c95da 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -23,7 +23,7 @@ struct vb2_dc_conf { }; struct vb2_dc_buf { - struct vb2_dc_conf *conf; + struct device *dev; void *vaddr; dma_addr_t dma_addr; unsigned long size; @@ -37,22 +37,21 @@ static void vb2_dc_put(void *buf_priv); static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size) { struct vb2_dc_conf *conf = alloc_ctx; + struct device *dev = conf->dev; struct vb2_dc_buf *buf; buf = kzalloc(sizeof *buf, GFP_KERNEL); if (!buf) return ERR_PTR(-ENOMEM); - buf->vaddr = dma_alloc_coherent(conf->dev, size, &buf->dma_addr, - GFP_KERNEL); + buf->vaddr = dma_alloc_coherent(dev, size, &buf->dma_addr, GFP_KERNEL); if (!buf->vaddr) { - dev_err(conf->dev, "dma_alloc_coherent of size %ld failed\n", - size); + dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size); kfree(buf); return ERR_PTR(-ENOMEM); } - buf->conf = conf; + buf->dev = dev; buf->size = size; buf->handler.refcount = &buf->refcount; @@ -69,7 +68,7 @@ static void vb2_dc_put(void *buf_priv) struct vb2_dc_buf *buf = buf_priv; if (atomic_dec_and_test(&buf->refcount)) { - dma_free_coherent(buf->conf->dev, buf->size, buf->vaddr, + dma_free_coherent(buf->dev, buf->size, buf->vaddr, buf->dma_addr); kfree(buf); } -- 1.7.9.5