Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935967AbcKKBAe (ORCPT ); Thu, 10 Nov 2016 20:00:34 -0500 Received: from galahad.ideasonboard.com ([185.26.127.97]:55320 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932614AbcKKBAc (ORCPT ); Thu, 10 Nov 2016 20:00:32 -0500 From: Laurent Pinchart To: Magnus Damm Cc: iommu@lists.linux-foundation.org, laurent.pinchart+renesas@ideasonboard.com, geert+renesas@glider.be, joro@8bytes.org, linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, horms+renesas@verge.net.au, robin.murphy@arm.com, m.szyprowski@samsung.com Subject: Re: [PATCH v6 03/07] iommu/ipmmu-vmsa: Break out utlb parsing code Date: Fri, 11 Nov 2016 03:00:33 +0200 Message-ID: <3032720.BPnZvxWODA@avalon> User-Agent: KMail/4.14.10 (Linux/4.8.6-gentoo; KDE/4.14.24; x86_64; ; ) In-Reply-To: <20161019233603.10506.93030.sendpatchset@little-apple> References: <20161019233533.10506.16810.sendpatchset@little-apple> <20161019233603.10506.93030.sendpatchset@little-apple> 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 Content-Length: 4405 Lines: 155 Hi Magnus, Thank you for the patch. On Thursday 20 Oct 2016 08:36:03 Magnus Damm wrote: > From: Magnus Damm > > Break out the utlb parsing code and dev_data allocation into a > separate function. This is preparation for future code sharing. > > Signed-off-by: Magnus Damm > Reviewed-by: Joerg Roedel > --- > > Changes since V5: > - None > > Changes since V4: > - Dropped hunk with fix to apply on top of: > b1e2afc iommu/ipmmu-vmsa: Fix wrong error handle of ipmmu_add_device > > Changes since V3: > - Initialize "mmu" to NULL, check before accessing > - Removed group parameter from ipmmu_init_platform_device() > > Changes since V2: > - Included this new patch from the following series: > [PATCH 00/04] iommu/ipmmu-vmsa: IPMMU CONFIG_IOMMU_DMA update > - Reworked code to fit on top on previous two patches in current series. > > drivers/iommu/ipmmu-vmsa.c | 58 ++++++++++++++++++++++++++--------------- > 1 file changed, 37 insertions(+), 21 deletions(-) > > --- 0006/drivers/iommu/ipmmu-vmsa.c > +++ work/drivers/iommu/ipmmu-vmsa.c 2016-09-20 21:49:34.580607110 +0900 > @@ -647,22 +647,15 @@ static int ipmmu_find_utlbs(struct ipmmu > return 0; > } > > -static int ipmmu_add_device(struct device *dev) > +static int ipmmu_init_platform_device(struct device *dev) The device doesn't have to be a platform device, how about calling this ipmmu_init_device_archdata() ? > { > struct ipmmu_vmsa_archdata *archdata; > struct ipmmu_vmsa_device *mmu; > - struct iommu_group *group = NULL; > unsigned int *utlbs; > unsigned int i; > int num_utlbs; > int ret = -ENODEV; > > - if (dev->archdata.iommu) { > - dev_warn(dev, "IOMMU driver already assigned to device %s\n", > - dev_name(dev)); > - return -EINVAL; > - } > - > /* Find the master corresponding to the device. */ > > num_utlbs = of_count_phandle_with_args(dev->of_node, "iommus", > @@ -699,6 +692,36 @@ static int ipmmu_add_device(struct devic > } > } > > + archdata = kzalloc(sizeof(*archdata), GFP_KERNEL); > + if (!archdata) { > + ret = -ENOMEM; > + goto error; > + } > + > + archdata->mmu = mmu; > + archdata->utlbs = utlbs; > + archdata->num_utlbs = num_utlbs; > + dev->archdata.iommu = archdata; > + return 0; > + > +error: > + kfree(utlbs); > + return ret; > +} > + > +static int ipmmu_add_device(struct device *dev) > +{ > + struct ipmmu_vmsa_archdata *archdata; > + struct ipmmu_vmsa_device *mmu = NULL; > + struct iommu_group *group; > + int ret; > + > + if (dev->archdata.iommu) { > + dev_warn(dev, "IOMMU driver already assigned to device %s\n", > + dev_name(dev)); > + return -EINVAL; > + } > + > /* Create a device group and add the device to it. */ > group = iommu_group_alloc(); > if (IS_ERR(group)) { > @@ -716,16 +739,9 @@ static int ipmmu_add_device(struct devic > goto error; > } > > - archdata = kzalloc(sizeof(*archdata), GFP_KERNEL); > - if (!archdata) { > - ret = -ENOMEM; > + ret = ipmmu_init_platform_device(dev); > + if (ret < 0) > goto error; > - } > - > - archdata->mmu = mmu; > - archdata->utlbs = utlbs; > - archdata->num_utlbs = num_utlbs; > - dev->archdata.iommu = archdata; > > /* > * Create the ARM mapping, used by the ARM DMA mapping core to allocate > @@ -736,6 +752,8 @@ static int ipmmu_add_device(struct devic > * - Make the mapping size configurable ? We currently use a 2GB mapping > * at a 1GB offset to ensure that NULL VAs will fault. > */ > + archdata = dev->archdata.iommu; > + mmu = archdata->mmu; > if (!mmu->mapping) { > struct dma_iommu_mapping *mapping; > > @@ -760,10 +778,8 @@ static int ipmmu_add_device(struct devic > return 0; > > error: > - arm_iommu_release_mapping(mmu->mapping); > - > - kfree(dev->archdata.iommu); > - kfree(utlbs); > + if (mmu) > + arm_iommu_release_mapping(mmu->mapping); Looking at the surrounding code, shouldn't the mapping only be destroyed here if it has been created by the same call to the function ? If there's an existing mapping for the IPMMU instance and the arm_iommu_attach_device() call fails, releasing the mapping seems to be a bug. As the bug isn't introduced by this patch, we can fix it separately, but if you end up resubmitting due to the first comment you could also add a fix. > > dev->archdata.iommu = NULL; -- Regards, Laurent Pinchart