From 4cbf38511a007867def958872203ae8adb8e2351 Mon Sep 17 00:00:00 2001 From: Sai Praneeth Prakhya Date: Wed, 29 Apr 2020 15:36:40 +0200 Subject: iommu: Add def_domain_type() callback in iommu_ops Some devices are reqired to use a specific type (identity or dma) of default domain when they are used with a vendor iommu. When the system level default domain type is different from it, the vendor iommu driver has to request a new default domain with iommu_request_dma_domain_for_dev() and iommu_request_dm_for_dev() in the add_dev() callback. Unfortunately, these two helpers only work when the group hasn't been assigned to any other devices, hence, some vendor iommu driver has to use a private domain if it fails to request a new default one. This adds def_domain_type() callback in the iommu_ops, so that any special requirement of default domain for a device could be aware by the iommu generic layer. Signed-off-by: Sai Praneeth Prakhya Signed-off-by: Lu Baolu [ jroedel@suse.de: Added iommu_get_def_domain_type() function and use it to allocate the default domain ] Co-developed-by: Joerg Roedel Signed-off-by: Joerg Roedel Tested-by: Marek Szyprowski Acked-by: Marek Szyprowski Link: https://lore.kernel.org/r/20200429133712.31431-3-joro@8bytes.org Signed-off-by: Joerg Roedel --- drivers/iommu/iommu.c | 20 +++++++++++++++++--- include/linux/iommu.h | 6 ++++++ 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index bfe011760ed1..5877abd9b693 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1361,21 +1361,35 @@ struct iommu_group *fsl_mc_device_group(struct device *dev) } EXPORT_SYMBOL_GPL(fsl_mc_device_group); +static int iommu_get_def_domain_type(struct device *dev) +{ + const struct iommu_ops *ops = dev->bus->iommu_ops; + unsigned int type = 0; + + if (ops->def_domain_type) + type = ops->def_domain_type(dev); + + return (type == 0) ? iommu_def_domain_type : type; +} + static int iommu_alloc_default_domain(struct device *dev, struct iommu_group *group) { struct iommu_domain *dom; + unsigned int type; if (group->default_domain) return 0; - dom = __iommu_domain_alloc(dev->bus, iommu_def_domain_type); - if (!dom && iommu_def_domain_type != IOMMU_DOMAIN_DMA) { + type = iommu_get_def_domain_type(dev); + + dom = __iommu_domain_alloc(dev->bus, type); + if (!dom && type != IOMMU_DOMAIN_DMA) { dom = __iommu_domain_alloc(dev->bus, IOMMU_DOMAIN_DMA); if (dom) { dev_warn(dev, "failed to allocate default IOMMU domain of type %u; falling back to IOMMU_DOMAIN_DMA", - iommu_def_domain_type); + type); } } diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 7ef8b0bda695..1f027b07e499 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -248,6 +248,10 @@ struct iommu_iotlb_gather { * @cache_invalidate: invalidate translation caches * @sva_bind_gpasid: bind guest pasid and mm * @sva_unbind_gpasid: unbind guest pasid and mm + * @def_domain_type: device default domain type, return value: + * - IOMMU_DOMAIN_IDENTITY: must use an identity domain + * - IOMMU_DOMAIN_DMA: must use a dma domain + * - 0: use the default setting * @pgsize_bitmap: bitmap of all possible supported page sizes * @owner: Driver module providing these ops */ @@ -318,6 +322,8 @@ struct iommu_ops { int (*sva_unbind_gpasid)(struct device *dev, int pasid); + int (*def_domain_type)(struct device *dev); + unsigned long pgsize_bitmap; struct module *owner; }; -- cgit v1.2.3-59-g8ed1b