From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754760AbdIGIqo (ORCPT ); Thu, 7 Sep 2017 04:46:44 -0400 Received: from smtpbgau2.qq.com ([54.206.34.216]:48259 "EHLO smtpbgau2.qq.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753826AbdIGIqn (ORCPT ); Thu, 7 Sep 2017 04:46:43 -0400 X-QQ-mid: bizesmtp16t1504773986tfrdrx22 X-QQ-SSF: 01100000002000F0FMF0B00A0000000 X-QQ-FEAT: p/Y2uUKTrszBpC+9kSKZv+RWJ61bRrr2ax4ef0z1JFtnaYHwov5dfOTYvMecO r/SnL+SxmfmvPhVWDF9WvrNWV+aP8WQwLNIXnwVBgvX55TK24lStXnjF0jOy9Vk7CdbsL5h 4Y9K8Tc/C32046L8+OS7zvQSNP271NZKXNWYuYU68Tz3k0SzZZ+FIIG0eACfcnyB6hcCHVd FOMTVni2vI9fjhGDMe8WBihDgUAA6HQ3XRT4QkhJbYUMz8jTHNt/pfrI6UOVHW6JzeZqH35 yMgzYEtz+xVSEX/0Ca6lUBce7UMW1EWhKEXulUUpBm5zgI X-QQ-GoodBg: 0 From: Huacai Chen To: Andrew Morton Cc: Fuxin Zhang , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huacai Chen , stable@vger.kernel.org Subject: [PATCH 1/2] mm: dmapool: Align to ARCH_DMA_MINALIGN in non-coherent DMA mode Date: Thu, 7 Sep 2017 16:47:51 +0800 Message-Id: <1504774071-11581-1-git-send-email-chenhc@lemote.com> X-Mailer: git-send-email 2.7.0 X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:lemote.com:qybgforeign:qybgforeign2 X-QQ-Bgrelay: 1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In non-coherent DMA mode, kernel uses cache flushing operations to maintain I/O coherency, so the dmapool objects should be aligned to ARCH_DMA_MINALIGN. Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen --- mm/dmapool.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/dmapool.c b/mm/dmapool.c index 4d90a64..2ac6f4a 100644 --- a/mm/dmapool.c +++ b/mm/dmapool.c @@ -140,6 +140,9 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev, else if (align & (align - 1)) return NULL; + if (!plat_device_is_coherent(dev)) + align = max_t(size_t, align, dma_get_cache_alignment()); + if (size == 0) return NULL; else if (size < 4) -- 2.7.0