From patchwork Tue Aug 14 15:34:50 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tomasz Stanislawski X-Patchwork-Id: 1323531 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by patchwork1.kernel.org (Postfix) with ESMTP id 0C1D33FD8C for ; Tue, 14 Aug 2012 21:29:00 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 193029F103 for ; Tue, 14 Aug 2012 14:29:00 -0700 (PDT) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mailout2.samsung.com (mailout2.samsung.com [203.254.224.25]) by gabe.freedesktop.org (Postfix) with ESMTP id 49E649E951 for ; Tue, 14 Aug 2012 08:37:48 -0700 (PDT) Received: from epcpsbgm2.samsung.com (mailout2.samsung.com [203.254.224.25]) by mailout2.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0M8R00BQ44QZGBC0@mailout2.samsung.com> for dri-devel@lists.freedesktop.org; Wed, 15 Aug 2012 00:37:47 +0900 (KST) X-AuditID: cbfee61b-b7faf6d00000476a-f9-502a70cba8be Received: from epmmp1.local.host ( [203.254.227.16]) by epcpsbgm2.samsung.com (EPCPMTA) with SMTP id 3B.1A.18282.BC07A205; Wed, 15 Aug 2012 00:37:47 +0900 (KST) Received: from mcdsrvbld02.digital.local ([106.116.37.23]) by mmp1.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTPA id <0M8R004J44MBC810@mmp1.samsung.com> for dri-devel@lists.freedesktop.org; Wed, 15 Aug 2012 00:37:47 +0900 (KST) From: Tomasz Stanislawski To: linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: [PATCHv8 20/26] v4l: vb2-dma-contig: add support for DMABUF exporting Date: Tue, 14 Aug 2012 17:34:50 +0200 Message-id: <1344958496-9373-21-git-send-email-t.stanislaws@samsung.com> X-Mailer: git-send-email 1.7.10 In-reply-to: <1344958496-9373-1-git-send-email-t.stanislaws@samsung.com> References: <1344958496-9373-1-git-send-email-t.stanislaws@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrEJMWRmVeSWpSXmKPExsVy+t9jAd3TBVoBBkv6eS2ufH3P5sDocb/7 OFMAYxSXTUpqTmZZapG+XQJXxv9LL5gK9htXtJ1ezN7A2KHVxcjBISFgInHjZHEXIyeQKSZx 4d56ti5GLg4hgUWMEtOWbGOEcNYxSRw5+JIJpIoNqOHYks+MILaIgIPE6buzmEGKmAUOMUvs 733NDpIQFvCT+HKznQ3EZhFQldi3aikziM0r4CHRseYkO8Q6eYmn9/vAajiB4i83dTOCXCQk 4C6x8Kf/BEbeBYwMqxhFUwuSC4qT0nON9IoTc4tL89L1kvNzNzGCff5MegfjqgaLQ4wCHIxK PLyFiZoBQqyJZcWVuYcYJTiYlUR4i4K0AoR4UxIrq1KL8uOLSnNSiw8xSnOwKInzmnh/9RcS SE8sSc1OTS1ILYLJMnFwSjUwKs3Nyzm26sW7XS3rDum0bBRnUupmmHS459hdyYvXc3t/rVfW bE95EXjkxLSami0MxfUTDSb67+XrsucVup/PpH5rS8W/hVySplKCbjYzd2arqm/YksZmkrb7 8aGG+Vc5VRP2ed98PYf9Ru1t2Y0mly5vb0x67P0lPler0SRmtV7RPzMBkb8LlViKMxINtZiL ihMBtxrzJPUBAAA= X-TM-AS-MML: No Cc: t.stanislaws@samsung.com, pawel@osciak.com, mchehab@redhat.com, daniel.vetter@ffwll.ch, subashrp@gmail.com, linaro-mm-sig@lists.linaro.org, kyungmin.park@samsung.com, laurent.pinchart@ideasonboard.com, s.nawrocki@samsung.com, airlied@redhat.com, remi@remlab.net, g.liakhovetski@gmx.de, m.szyprowski@samsung.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org Errors-To: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org This patch adds support for exporting a dma-contig buffer using DMABUF interface. Signed-off-by: Tomasz Stanislawski Signed-off-by: Kyungmin Park --- drivers/media/video/videobuf2-dma-contig.c | 204 ++++++++++++++++++++++++++++ 1 file changed, 204 insertions(+) diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c index 7fc71a0..bb2b4ac8 100644 --- a/drivers/media/video/videobuf2-dma-contig.c +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -36,6 +36,7 @@ struct vb2_dc_buf { /* MMAP related */ struct vb2_vmarea_handler handler; atomic_t refcount; + struct sg_table *sgt_base; /* USERPTR related */ struct vm_area_struct *vma; @@ -142,6 +143,10 @@ static void vb2_dc_put(void *buf_priv) if (!atomic_dec_and_test(&buf->refcount)) return; + if (buf->sgt_base) { + sg_free_table(buf->sgt_base); + kfree(buf->sgt_base); + } dma_free_coherent(buf->dev, buf->size, buf->vaddr, buf->dma_addr); kfree(buf); } @@ -213,6 +218,204 @@ static int vb2_dc_mmap(void *buf_priv, struct vm_area_struct *vma) } /*********************************************/ +/* DMABUF ops for exporters */ +/*********************************************/ + +struct vb2_dc_attachment { + struct sg_table sgt; + enum dma_data_direction dir; +}; + +static int vb2_dc_dmabuf_ops_attach(struct dma_buf *dbuf, struct device *dev, + struct dma_buf_attachment *dbuf_attach) +{ + struct vb2_dc_attachment *attach; + unsigned int i; + struct scatterlist *rd, *wr; + struct sg_table *sgt; + struct vb2_dc_buf *buf = dbuf->priv; + int ret; + + attach = kzalloc(sizeof(*attach), GFP_KERNEL); + if (!attach) + return -ENOMEM; + + sgt = &attach->sgt; + /* Copy the buf->base_sgt scatter list to the attachment, as we can't + * map the same scatter list to multiple attachments at the same time. + */ + ret = sg_alloc_table(sgt, buf->sgt_base->orig_nents, GFP_KERNEL); + if (ret) { + kfree(attach); + return -ENOMEM; + } + + rd = buf->sgt_base->sgl; + wr = sgt->sgl; + for (i = 0; i < sgt->orig_nents; ++i) { + sg_set_page(wr, sg_page(rd), rd->length, rd->offset); + rd = sg_next(rd); + wr = sg_next(wr); + } + + attach->dir = DMA_NONE; + dbuf_attach->priv = attach; + + return 0; +} + +static void vb2_dc_dmabuf_ops_detach(struct dma_buf *dbuf, + struct dma_buf_attachment *db_attach) +{ + struct vb2_dc_attachment *attach = db_attach->priv; + struct sg_table *sgt; + + if (!attach) + return; + + sgt = &attach->sgt; + + /* release the scatterlist cache */ + if (attach->dir != DMA_NONE) + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dir); + sg_free_table(sgt); + kfree(attach); + db_attach->priv = NULL; +} + +static struct sg_table *vb2_dc_dmabuf_ops_map( + struct dma_buf_attachment *db_attach, enum dma_data_direction dir) +{ + struct vb2_dc_attachment *attach = db_attach->priv; + /* stealing dmabuf mutex to serialize map/unmap operations */ + struct mutex *lock = &db_attach->dmabuf->lock; + struct sg_table *sgt; + int ret; + + mutex_lock(lock); + + sgt = &attach->sgt; + /* return previously mapped sg table */ + if (attach->dir == dir) { + mutex_unlock(lock); + return sgt; + } + + /* release any previous cache */ + if (attach->dir != DMA_NONE) { + dma_unmap_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, + attach->dir); + attach->dir = DMA_NONE; + } + + /* mapping to the client with new direction */ + ret = dma_map_sg(db_attach->dev, sgt->sgl, sgt->orig_nents, dir); + if (ret <= 0) { + pr_err("failed to map scatterlist\n"); + mutex_unlock(lock); + return ERR_PTR(-EIO); + } + + attach->dir = dir; + + mutex_unlock(lock); + + return sgt; +} + +static void vb2_dc_dmabuf_ops_unmap(struct dma_buf_attachment *db_attach, + struct sg_table *sgt, enum dma_data_direction dir) +{ + /* nothing to be done here */ +} + +static void vb2_dc_dmabuf_ops_release(struct dma_buf *dbuf) +{ + /* drop reference obtained in vb2_dc_get_dmabuf */ + vb2_dc_put(dbuf->priv); +} + +static void *vb2_dc_dmabuf_ops_kmap(struct dma_buf *dbuf, unsigned long pgnum) +{ + struct vb2_dc_buf *buf = dbuf->priv; + + return buf->vaddr + pgnum * PAGE_SIZE; +} + +static void *vb2_dc_dmabuf_ops_vmap(struct dma_buf *dbuf) +{ + struct vb2_dc_buf *buf = dbuf->priv; + + return buf->vaddr; +} + +static int vb2_dc_dmabuf_ops_mmap(struct dma_buf *dbuf, + struct vm_area_struct *vma) +{ + /* Dummy support for mmap */ + return -ENOTTY; +} + +static struct dma_buf_ops vb2_dc_dmabuf_ops = { + .attach = vb2_dc_dmabuf_ops_attach, + .detach = vb2_dc_dmabuf_ops_detach, + .map_dma_buf = vb2_dc_dmabuf_ops_map, + .unmap_dma_buf = vb2_dc_dmabuf_ops_unmap, + .kmap = vb2_dc_dmabuf_ops_kmap, + .kmap_atomic = vb2_dc_dmabuf_ops_kmap, + .vmap = vb2_dc_dmabuf_ops_vmap, + .mmap = vb2_dc_dmabuf_ops_mmap, + .release = vb2_dc_dmabuf_ops_release, +}; + +static struct sg_table *vb2_dc_get_base_sgt(struct vb2_dc_buf *buf) +{ + int ret; + struct sg_table *sgt; + + sgt = kmalloc(sizeof(*sgt), GFP_KERNEL); + if (!sgt) { + dev_err(buf->dev, "failed to alloc sg table\n"); + return ERR_PTR(-ENOMEM); + } + + ret = dma_get_sgtable(buf->dev, sgt, buf->vaddr, buf->dma_addr, + buf->size); + if (ret < 0) { + dev_err(buf->dev, "failed to get scatterlist from DMA API\n"); + kfree(sgt); + return ERR_PTR(ret); + } + + return sgt; +} + +static struct dma_buf *vb2_dc_get_dmabuf(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + struct dma_buf *dbuf; + struct sg_table *sgt = buf->sgt_base; + + if (!sgt) + sgt = vb2_dc_get_base_sgt(buf); + if (WARN_ON(IS_ERR(sgt))) + return NULL; + + /* cache base sgt for future use */ + buf->sgt_base = sgt; + + dbuf = dma_buf_export(buf, &vb2_dc_dmabuf_ops, buf->size, 0); + if (IS_ERR(dbuf)) + return NULL; + + /* dmabuf keeps reference to vb2 buffer */ + atomic_inc(&buf->refcount); + + return dbuf; +} + +/*********************************************/ /* callbacks for USERPTR buffers */ /*********************************************/ @@ -519,6 +722,7 @@ static void *vb2_dc_attach_dmabuf(void *alloc_ctx, struct dma_buf *dbuf, const struct vb2_mem_ops vb2_dma_contig_memops = { .alloc = vb2_dc_alloc, .put = vb2_dc_put, + .get_dmabuf = vb2_dc_get_dmabuf, .cookie = vb2_dc_cookie, .vaddr = vb2_dc_vaddr, .mmap = vb2_dc_mmap,