[PATCH v6 19/25] iommu/mtk_iommu: Add an IOMMU_IDENTITIY_DOMAIN

Jason Gunthorpe
2023-08-03T00:10:16Z

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

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
drivers/iommu/mtk_iommu.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index e93906d6e112e8..fdb7f5162b1d64 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -753,6 +753,28 @@ static int mtk_iommu_attach_device(struct iommu_domain *domain,
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)
@@ -972,6 +994,7 @@ 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,
--
2.41.0