[PATCH RFCv2 24/24] iommu/arm-smmu-v3: Advertise IOMMU_DOMAIN_F_ENFORCE_DIRTY

From: Joao Martins <joao.m.martins@oracle.com>
To: iommu@lists.linux.dev
Cc: Jason Gunthorpe <jgg@nvidia.com>,
	Kevin Tian <kevin.tian@intel.com>,
	Shameerali Kolothum Thodi  <shameerali.kolothum.thodi@huawei.com>,
	Lu Baolu <baolu.lu@linux.intel.com>, Yi Liu <yi.l.liu@intel.com>,
	Yi Y Sun <yi.y.sun@intel.com>, Eric Auger <eric.auger@redhat.com>,
	Nicolin Chen <nicolinc@nvidia.com>,
	Joerg Roedel <joro@8bytes.org>,
	Jean-Philippe Brucker <jean-philippe@linaro.org>,
	Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
	Will Deacon <will@kernel.org>,
	Robin Murphy <robin.murphy@arm.com>,
	Alex Williamson <alex.williamson@redhat.com>,
	kvm@vger.kernel.org, Joao Martins <joao.m.martins@oracle.com>
Subject: [PATCH RFCv2 24/24] iommu/arm-smmu-v3: Advertise IOMMU_DOMAIN_F_ENFORCE_DIRTY
Date: Thu, 18 May 2023 21:46:50 +0100	[thread overview]
Message-ID: <20230518204650.14541-25-joao.m.martins@oracle.com> (raw)
In-Reply-To: <20230518204650.14541-1-joao.m.martins@oracle.com>

Now that we probe, and handle the DBM bit modifier, unblock
the kAPI usage by exposing the IOMMU_DOMAIN_F_ENFORCE_DIRTY
and implement it's requirement of revoking device attachment
in the iommu_capable. Finally expose the IOMMU_CAP_DIRTY to
users (IOMMUFD_DEVICE_GET_CAPS).

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index bf0aac333725..71dd95a687fd 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2014,6 +2014,8 @@ static bool arm_smmu_capable(struct device *dev, enum iommu_cap cap)
 		return master->smmu->features & ARM_SMMU_FEAT_COHERENCY;
 	case IOMMU_CAP_NOEXEC:
 		return true;
+	case IOMMU_CAP_DIRTY:
+		return arm_smmu_dbm_capable(master->smmu);
 	default:
 		return false;
 	}
@@ -2430,6 +2432,11 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
 	master = dev_iommu_priv_get(dev);
 	smmu = master->smmu;
 
+	if (domain->flags & IOMMU_DOMAIN_F_ENFORCE_DIRTY &&
+	    !arm_smmu_dbm_capable(smmu))
+		return -EINVAL;
+
+
 	/*
 	 * Checking that SVA is disabled ensures that this device isn't bound to
 	 * any mm, and can be safely detached from its old domain. Bonds cannot
@@ -2913,6 +2920,7 @@ static void arm_smmu_remove_dev_pasid(struct device *dev, ioasid_t pasid)
 }
 
 static struct iommu_ops arm_smmu_ops = {
+	.supported_flags	= IOMMU_DOMAIN_F_ENFORCE_DIRTY,
 	.capable		= arm_smmu_capable,
 	.domain_alloc		= arm_smmu_domain_alloc,
 	.probe_device		= arm_smmu_probe_device,
-- 
2.17.2

