diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index d199d144460c..e385a99e25e1 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -960,14 +960,12 @@ static int iommu_create_device_direct_mappings(struct iommu_domain *domain, unsigned long pg_size; int ret = 0; - if (!iommu_is_dma_domain(domain)) - return 0; - - BUG_ON(!domain->pgsize_bitmap); - - pg_size = 1UL << __ffs(domain->pgsize_bitmap); + pg_size = domain->pgsize_bitmap ? 1UL << __ffs(domain->pgsize_bitmap) : 0; INIT_LIST_HEAD(&mappings); + if (WARN_ON_ONCE(iommu_is_dma_domain(domain) && !pg_size)) + return -EINVAL; + iommu_get_resv_regions(dev, &mappings); /* We need to consider overlapping regions for different devices */ @@ -975,13 +973,17 @@ static int iommu_create_device_direct_mappings(struct iommu_domain *domain, dma_addr_t start, end, addr; size_t map_size = 0; + if (entry->type == IOMMU_RESV_DIRECT) + dev->iommu->require_direct = 1; + + if ((entry->type != IOMMU_RESV_DIRECT && + entry->type != IOMMU_RESV_DIRECT_RELAXABLE) || + !iommu_is_dma_domain(domain)) + continue; + start = ALIGN(entry->start, pg_size); end = ALIGN(entry->start + entry->length, pg_size); - if (entry->type != IOMMU_RESV_DIRECT && - entry->type != IOMMU_RESV_DIRECT_RELAXABLE) - continue; - for (addr = start; addr <= end; addr += pg_size) { phys_addr_t phys_addr; @@ -2122,6 +2124,21 @@ static int __iommu_device_set_domain(struct iommu_group *group, { int ret; + /* + * If the device requires IOMMU_RESV_DIRECT then we cannot allow + * the blocking domain to be attached as it does not contain the + * required 1:1 mapping. This test effectively excludes the device + * being used with iommu_group_claim_dma_owner() which will block + * vfio and iommufd as well. + */ + if (dev->iommu->require_direct && + (new_domain->type == IOMMU_DOMAIN_BLOCKED || + new_domain == group->blocking_domain)) { + dev_warn(dev, + "Firmware has requested this device have a 1:1 IOMMU mapping, rejecting configuring the device without a 1:1 mapping. Contact your platform vendor.\n"); + return -EINVAL; + } + if (dev->iommu->attach_deferred) { if (new_domain == group->default_domain) return 0; diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 6b821cb715d5..54bae452975f 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -411,6 +411,7 @@ struct iommu_fault_param { * @priv: IOMMU Driver private data * @max_pasids: number of PASIDs this device can consume * @attach_deferred: the dma domain attachment is deferred + * @require_direct: device requires IOMMU_RESV_DIRECT regions * * TODO: migrate other per device data pointers under iommu_dev_data, e.g. * struct iommu_group *iommu_group; @@ -424,6 +425,7 @@ struct dev_iommu { void *priv; u32 max_pasids; u32 attach_deferred:1; + u32 require_direct:1; }; int iommu_device_register(struct iommu_device *iommu,