iommu/mtk_iommu: Add an IOMMU_IDENTITIY_DOMAIN

This brings back the ops->detach_dev() code that commit
1b932ceddd19 ("iommu: Remove detach_dev callbacks") deleted and turns it
into an IDENTITY domain.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/18-v8-81230027b2fa+9d-iommu_all_defdom_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 640275873a271ec7806083df05003f7fe5237754..164f9759e1c03981b6da72046e650cbe2bbefd48 100644 (file)
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -777,6 +777,28 @@ err_unlock:
        return ret;
 }
 
+static int mtk_iommu_identity_attach(struct iommu_domain *identity_domain,
+                                    struct device *dev)
+{
+       struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+       struct mtk_iommu_data *data = dev_iommu_priv_get(dev);
+
+       if (domain == identity_domain || !domain)
+               return 0;
+
+       mtk_iommu_config(data, dev, false, 0);
+       return 0;
+}
+
+static struct iommu_domain_ops mtk_iommu_identity_ops = {
+       .attach_dev = mtk_iommu_identity_attach,
+};
+
+static struct iommu_domain mtk_iommu_identity_domain = {
+       .type = IOMMU_DOMAIN_IDENTITY,
+       .ops = &mtk_iommu_identity_ops,
+};
+
 static int mtk_iommu_map(struct iommu_domain *domain, unsigned long iova,
                         phys_addr_t paddr, size_t pgsize, size_t pgcount,
                         int prot, gfp_t gfp, size_t *mapped)
@@ -996,6 +1018,7 @@ static void mtk_iommu_get_resv_regions(struct device *dev,
 }
 
 static const struct iommu_ops mtk_iommu_ops = {
+       .identity_domain = &mtk_iommu_identity_domain,
        .domain_alloc   = mtk_iommu_domain_alloc,
        .probe_device   = mtk_iommu_probe_device,
        .release_device = mtk_iommu_release_device,