Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751762AbdCBVpD (ORCPT ); Thu, 2 Mar 2017 16:45:03 -0500 Received: from mail-qk0-f181.google.com ([209.85.220.181]:34220 "EHLO mail-qk0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751135AbdCBVpB (ORCPT ); Thu, 2 Mar 2017 16:45:01 -0500 From: Laura Abbott To: Sumit Semwal , Riley Andrews , arve@android.com Cc: Laura Abbott , romlem@google.com, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, linaro-mm-sig@lists.linaro.org, Greg Kroah-Hartman , linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, Brian Starkey , Daniel Vetter , Mark Brown , Benjamin Gaignard , linux-mm@kvack.org Subject: [RFC PATCH 03/12] staging: android: ion: Duplicate sg_table Date: Thu, 2 Mar 2017 13:44:35 -0800 Message-Id: <1488491084-17252-4-git-send-email-labbott@redhat.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1488491084-17252-1-git-send-email-labbott@redhat.com> References: <1488491084-17252-1-git-send-email-labbott@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1893 Lines: 65 Ion currently returns a single sg_table on each dma_map call. This is incorrect for later usage. Signed-off-by: Laura Abbott --- drivers/staging/android/ion/ion.c | 30 +++++++++++++++++++++++++++++- 1 file changed, 29 insertions(+), 1 deletion(-) diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c index 94a498e..ce4adac 100644 --- a/drivers/staging/android/ion/ion.c +++ b/drivers/staging/android/ion/ion.c @@ -799,6 +799,32 @@ static void ion_buffer_sync_for_device(struct ion_buffer *buffer, struct device *dev, enum dma_data_direction direction); +static struct sg_table *dup_sg_table(struct sg_table *table) +{ + struct sg_table *new_table; + int ret, i; + struct scatterlist *sg, *new_sg; + + new_table = kzalloc(sizeof(*new_table), GFP_KERNEL); + if (!new_table) + return ERR_PTR(-ENOMEM); + + ret = sg_alloc_table(new_table, table->nents, GFP_KERNEL); + if (ret) { + kfree(table); + return ERR_PTR(-ENOMEM); + } + + new_sg = new_table->sgl; + for_each_sg(table->sgl, sg, table->nents, i) { + memcpy(new_sg, sg, sizeof(*sg)); + sg->dma_address = 0; + new_sg = sg_next(new_sg); + } + + return new_table; +} + static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment, enum dma_data_direction direction) { @@ -806,13 +832,15 @@ static struct sg_table *ion_map_dma_buf(struct dma_buf_attachment *attachment, struct ion_buffer *buffer = dmabuf->priv; ion_buffer_sync_for_device(buffer, attachment->dev, direction); - return buffer->sg_table; + return dup_sg_table(buffer->sg_table); } static void ion_unmap_dma_buf(struct dma_buf_attachment *attachment, struct sg_table *table, enum dma_data_direction direction) { + sg_free_table(table); + kfree(table); } void ion_pages_sync_for_device(struct device *dev, struct page *page, -- 2.7.4