From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751569AbbEXWiY (ORCPT ); Sun, 24 May 2015 18:38:24 -0400 Received: from galahad.ideasonboard.com ([185.26.127.97]:38712 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750980AbbEXWiW (ORCPT ); Sun, 24 May 2015 18:38:22 -0400 From: Laurent Pinchart To: Robin Murphy Cc: Laurent Pinchart , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "iommu@lists.linux-foundation.org" , Laura Abbott , Arnd Bergmann , Mitchel Humpherys , Joreg Roedel , Will Deacon , "grant.likely@linaro.org" , Marek Szyprowski , Thierry Reding , Greg Kroah-Hartman Subject: Re: [RFC/PATCH 2/9] arm: dma-mapping: Support IOMMU mappings spanning the full 32 bits range Date: Mon, 25 May 2015 01:38:40 +0300 Message-ID: <3504657.zdfVEnYr60@avalon> User-Agent: KMail/4.14.3 (Linux/3.18.11-gentoo; KDE/4.14.3; x86_64; ; ) In-Reply-To: <555B0DBC.6090204@arm.com> References: <1431644410-2997-1-git-send-email-laurent.pinchart+renesas@ideasonboard.com> <1431644410-2997-3-git-send-email-laurent.pinchart+renesas@ideasonboard.com> <555B0DBC.6090204@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Robin, On Tuesday 19 May 2015 11:17:32 Robin Murphy wrote: > On 15/05/15 00:00, Laurent Pinchart wrote: > > The arm_iommu_create_mapping() function takes the IOMMU mapping size as > > a size_t, limiting the size to 4GB - 1 on 32 bit platforms while most > > bus masters would support the full 32 bits range. Fix this by passing > > the size as a 64 bits integer, and limiting it to 4GB for now. > > FYI there's already an almost-identical patch in -rc3 from Marek fixing > this: 1424532b2163 ("ARM: 8347/1: dma-mapping: fix off-by-one check in > arm_setup_iommu_dma_ops"). Indeed, I should have rebased on top of -rc3. I suppose it's a good indication that I was on the right track :-) I'll drop this patch from my series. > > Signed-off-by: Laurent Pinchart > > > > --- > > > > arch/arm/include/asm/dma-iommu.h | 2 +- > > arch/arm/mm/dma-mapping.c | 12 +++--------- > > 2 files changed, 4 insertions(+), 10 deletions(-) > > > > diff --git a/arch/arm/include/asm/dma-iommu.h > > b/arch/arm/include/asm/dma-iommu.h index 8e3fcb924db6..2ef282f96651 > > 100644 > > --- a/arch/arm/include/asm/dma-iommu.h > > +++ b/arch/arm/include/asm/dma-iommu.h > > @@ -25,7 +25,7 @@ struct dma_iommu_mapping { > > }; > > > > struct dma_iommu_mapping * > > -arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t > > size); > > +arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, u64 > > size); > > void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping); > > > > diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c > > index 7aa5e339a596..c69e216a0cf9 100644 > > --- a/arch/arm/mm/dma-mapping.c > > +++ b/arch/arm/mm/dma-mapping.c > > @@ -1878,7 +1878,7 @@ struct dma_map_ops iommu_coherent_ops = { > > > > * arm_iommu_attach_device function. > > */ > > > > struct dma_iommu_mapping * > > > > -arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t > > size) +arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, > > u64 size) > > { > > unsigned int bits = size >> PAGE_SHIFT; > > unsigned int bitmap_size = BITS_TO_LONGS(bits) * sizeof(long); > > @@ -1886,7 +1886,8 @@ arm_iommu_create_mapping(struct bus_type *bus, > > dma_addr_t base, size_t size) > > int extensions = 1; > > int err = -ENOMEM; > > > > - if (!bitmap_size) > > + /* Limit the size to 4GB for now. */ > > + if (!size || size > (1ULL << 32)) > > return ERR_PTR(-EINVAL); > > > > if (bitmap_size > PAGE_SIZE) { > > @@ -2057,13 +2058,6 @@ static bool arm_setup_iommu_dma_ops(struct device > > *dev, u64 dma_base, u64 size, > > if (!iommu) > > return false; > > > > - /* > > - * currently arm_iommu_create_mapping() takes a max of size_t > > - * for size param. So check this limit for now. > > - */ > > - if (size > SIZE_MAX) > > - return false; > > - > > mapping = arm_iommu_create_mapping(dev->bus, dma_base, size); > > if (IS_ERR(mapping)) { > > pr_warn("Failed to create %llu-byte IOMMU mapping for device %s\n", -- Regards, Laurent Pinchart