From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: [PATCH 3/4] iommu/arm-smmu: handle multi-alias IOMMU groups for PCI devices Date: Fri, 20 Mar 2015 18:15:36 +0000 Message-ID: <1426875337-12808-4-git-send-email-will.deacon@arm.com> References: <1426875337-12808-1-git-send-email-will.deacon@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1426875337-12808-1-git-send-email-will.deacon-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Cc: Will Deacon , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: iommu@lists.linux-foundation.org IOMMU groups for PCI devices can correspond to multiple DMA aliases due to things like ACS and PCI quirks. This patch extends the ARM SMMU ->add_device callback so that we consider all of the DMA aliases for a PCI IOMMU group, rather than creating a separate group for each Requester ID. Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu.c | 92 ++++++++++++++++++++++++++++++------------------ 1 file changed, 57 insertions(+), 35 deletions(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 161dd46999e2..6ac184669295 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1330,61 +1330,83 @@ static void __arm_smmu_release_pci_iommudata(void *data) kfree(data); } -static int arm_smmu_add_device(struct device *dev) +static int arm_smmu_add_pci_device(struct pci_dev *pdev) { - struct arm_smmu_device *smmu; - struct arm_smmu_master_cfg *cfg; + int i, ret; + u16 sid; struct iommu_group *group; - void (*releasefn)(void *) = NULL; - int ret; - - smmu = find_smmu_for_device(dev); - if (!smmu) - return -ENODEV; + struct arm_smmu_master_cfg *cfg; - group = iommu_group_alloc(); - if (IS_ERR(group)) { - dev_err(dev, "Failed to allocate IOMMU group\n"); + group = iommu_group_get_for_dev(&pdev->dev); + if (IS_ERR(group)) return PTR_ERR(group); - } - - if (dev_is_pci(dev)) { - struct pci_dev *pdev = to_pci_dev(dev); + cfg = iommu_group_get_iommudata(group); + if (!cfg) { cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); if (!cfg) { ret = -ENOMEM; goto out_put_group; } - cfg->num_streamids = 1; - /* - * Assume Stream ID == Requester ID for now. - * We need a way to describe the ID mappings in FDT. - */ - pci_for_each_dma_alias(pdev, __arm_smmu_get_pci_sid, - &cfg->streamids[0]); - releasefn = __arm_smmu_release_pci_iommudata; - } else { - struct arm_smmu_master *master; - - master = find_smmu_master(smmu, dev->of_node); - if (!master) { - ret = -ENODEV; - goto out_put_group; - } + iommu_group_set_iommudata(group, cfg, + __arm_smmu_release_pci_iommudata); + } - cfg = &master->cfg; + if (cfg->num_streamids >= MAX_MASTER_STREAMIDS) { + ret = -ENOSPC; + goto out_put_group; } - iommu_group_set_iommudata(group, cfg, releasefn); - ret = iommu_group_add_device(group, dev); + /* + * Assume Stream ID == Requester ID for now. + * We need a way to describe the ID mappings in FDT. + */ + pci_for_each_dma_alias(pdev, __arm_smmu_get_pci_sid, &sid); + for (i = 0; i < cfg->num_streamids; ++i) + if (cfg->streamids[i] == sid) + break; + + /* Avoid duplicate SIDs, as this can lead to SMR conflicts */ + if (i == cfg->num_streamids) + cfg->streamids[cfg->num_streamids++] = sid; + return 0; out_put_group: iommu_group_put(group); return ret; } +static int arm_smmu_add_platform_device(struct device *dev) +{ + struct iommu_group *group; + struct arm_smmu_master *master; + struct arm_smmu_device *smmu = find_smmu_for_device(dev); + + if (!smmu) + return -ENODEV; + + master = find_smmu_master(smmu, dev->of_node); + if (!master) + return -ENODEV; + + /* No automatic group creation for platform devices */ + group = iommu_group_alloc(); + if (IS_ERR(group)) + return PTR_ERR(group); + + iommu_group_set_iommudata(group, &master->cfg, NULL); + return iommu_group_add_device(group, dev); +} + +static int arm_smmu_add_device(struct device *dev) +{ + if (dev_is_pci(dev)) + return arm_smmu_add_pci_device(to_pci_dev(dev)); + + return arm_smmu_add_platform_device(dev); +} + static void arm_smmu_remove_device(struct device *dev) { iommu_group_remove_device(dev); -- 2.1.4