From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751303AbaETF5v (ORCPT ); Tue, 20 May 2014 01:57:51 -0400 Received: from LGEMRELSE7Q.lge.com ([156.147.1.151]:55072 "EHLO lgemrelse7q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750745AbaETF5u (ORCPT ); Tue, 20 May 2014 01:57:50 -0400 X-Original-SENDERIP: 10.178.33.69 X-Original-MAILFROM: gioh.kim@lge.com Message-ID: <537AEEDB.2000001@lge.com> Date: Tue, 20 May 2014 14:57:47 +0900 From: Gioh Kim User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: =?EUC-KR?B?J7Howdi89ic=?= , Marek Szyprowski , Michal Nazarewicz , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Heesub Shin , Mel Gorman , Johannes Weiner CC: =?EUC-KR?B?wMywx8ij?= Subject: [RFC PATCH] arm: dma-mapping: fallback allocation for cma failure Content-Type: text/plain; charset=EUC-KR Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thanks for your advise, Michal Nazarewicz. Having discuss with Joonsoo, I'm adding fallback allocation after __alloc_from_contiguous(). The fallback allocation works if CMA kernel options is turned on but CMA size is zero. --------------------- 8< ------------------------ >>From 05e389683ddd07027e8acb61c25f3284f762300e Mon Sep 17 00:00:00 2001 From: Gioh Kim Date: Tue, 20 May 2014 14:16:20 +0900 Subject: [PATCH] arm: dma-mapping: fallback allocation for cma failure If CMA is turned on and CMA size is set to zero, kernel should behave as if CMA was not enabled at compile time. Fallback allocation is added for CMA allocation failure. Signed-off-by: Gioh Kim Signed-off-by: Joonsoo Kim --- arch/arm/mm/dma-mapping.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 18e98df..2a6c883 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -379,7 +379,7 @@ static int __init atomic_pool_init(void) unsigned long *bitmap; struct page *page; struct page **pages; - void *ptr; + void *ptr = NULL; int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long); bitmap = kzalloc(bitmap_size, GFP_KERNEL); @@ -393,9 +393,10 @@ static int __init atomic_pool_init(void) if (IS_ENABLED(CONFIG_DMA_CMA)) ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page, atomic_pool_init); - else + if (!ptr) ptr = __alloc_remap_buffer(NULL, pool->size, gfp, prot, &page, atomic_pool_init); + if (ptr) { int i; @@ -703,8 +704,12 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, addr = __alloc_from_pool(size, &page); else if (!IS_ENABLED(CONFIG_DMA_CMA)) addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller); - else + else { addr = __alloc_from_contiguous(dev, size, prot, &page, caller); + if (!addr) + addr = __alloc_remap_buffer(dev, size, gfp, prot, + &page, caller); + } if (addr) *handle = pfn_to_dma(dev, page_to_pfn(page)); -- 1.7.9.5