From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx201.postini.com [74.125.245.201]) by kanga.kvack.org (Postfix) with SMTP id EA9F56B005D for ; Wed, 22 Aug 2012 08:30:04 -0400 (EDT) Received: from epcpsbgm1.samsung.com (mailout1.samsung.com [203.254.224.24]) by mailout1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0M9500L4LPE342D0@mailout1.samsung.com> for linux-mm@kvack.org; Wed, 22 Aug 2012 21:30:03 +0900 (KST) Received: from AMDC159 ([106.116.147.30]) by mmp1.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTPA id <0M9500I3OPDOJN70@mmp1.samsung.com> for linux-mm@kvack.org; Wed, 22 Aug 2012 21:30:03 +0900 (KST) From: Marek Szyprowski References: <1345630830-9586-1-git-send-email-hdoyu@nvidia.com> <1345630830-9586-3-git-send-email-hdoyu@nvidia.com> In-reply-to: <1345630830-9586-3-git-send-email-hdoyu@nvidia.com> Subject: RE: [RFC 2/4] ARM: dma-mapping: IOMMU allocates pages from pool with GFP_ATOMIC Date: Wed, 22 Aug 2012 14:29:47 +0200 Message-id: <005a01cd8061$d58998c0$809cca40$%szyprowski@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit Content-language: pl Sender: owner-linux-mm@kvack.org List-ID: To: 'Hiroshi Doyu' Cc: linux-arm-kernel@lists.infradead.org, linaro-mm-sig@lists.linaro.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kyungmin.park@samsung.com, arnd@arndb.de, linux@arm.linux.org.uk, chunsang.jeong@linaro.org, 'Krishna Reddy' , konrad.wilk@oracle.com, subashrp@gmail.com, minchan@kernel.org Hello, On Wednesday, August 22, 2012 12:20 PM Hiroshi Doyu wrote: > Makes use of the same atomic pool from DMA, and skips kernel page > mapping which can involves sleep'able operation at allocating a kernel > page table. > > Signed-off-by: Hiroshi Doyu > --- > arch/arm/mm/dma-mapping.c | 22 ++++++++++++++++++---- > 1 files changed, 18 insertions(+), 4 deletions(-) > > diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c > index aec0c06..9260107 100644 > --- a/arch/arm/mm/dma-mapping.c > +++ b/arch/arm/mm/dma-mapping.c > @@ -1028,7 +1028,6 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t > size, > struct page **pages; > int count = size >> PAGE_SHIFT; > int array_size = count * sizeof(struct page *); > - int err; > > if (array_size <= PAGE_SIZE) > pages = kzalloc(array_size, gfp); > @@ -1037,9 +1036,20 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t > size, > if (!pages) > return NULL; > > - err = __alloc_fill_pages(&pages, count, gfp); > - if (err) > - goto error > + if (gfp & GFP_ATOMIC) { > + struct page *page; > + int i; > + void *addr = __alloc_from_pool(size, &page); > + if (!addr) > + goto err_out; > + > + for (i = 0; i < count; i++) > + pages[i] = page + i; > + } else { > + int err = __alloc_fill_pages(&pages, count, gfp); > + if (err) > + goto error; > + } > > return pages; > error: > @@ -1055,6 +1065,10 @@ static int __iommu_free_buffer(struct device *dev, struct page **pages, > size_t s > int count = size >> PAGE_SHIFT; > int array_size = count * sizeof(struct page *); > int i; > + > + if (__free_from_pool(page_address(pages[0]), size)) > + return 0; You leak memory here. pages array should be also freed. > + > for (i = 0; i < count; i++) > if (pages[i]) > __free_pages(pages[i], 0); > -- > 1.7.5.4 Best regards -- Marek Szyprowski Samsung Poland R&D Center -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org