[PATCH v2 5/6] iommu/dma: Simplify calls to iommu_setup_dma_ops()

Jean-Philippe Brucker
Fri, 23 Apr 2021 11:38:36 -0000

dma-iommu uses the address bounds described in domain->geometry during
IOVA allocation. The address size parameters of iommu_setup_dma_ops()
are useful for describing additional limits set by the platform
firmware, but aren't needed for drivers that call this function from
probe_finalize(). The base parameter can be zero because dma-iommu
already removes the first IOVA page, and the limit parameter can be
U64_MAX because it's only checked against the domain geometry. Simplify
calls to iommu_setup_dma_ops().

Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 drivers/iommu/amd/iommu.c   |  9 +--------
 drivers/iommu/dma-iommu.c   |  4 +++-
 drivers/iommu/intel/iommu.c | 10 +---------
 3 files changed, 5 insertions(+), 18 deletions(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 50041df43391..bbb09840cf40 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1708,14 +1708,7 @@ static struct iommu_device *amd_iommu_probe_device(struct
device *dev)

 static void amd_iommu_probe_finalize(struct device *dev)
 {
-	struct iommu_domain *domain;
-
-	/* Domains are initialized for this device - have a look what we ended up with
*/
-	domain = iommu_get_domain_for_dev(dev);
-	if (domain->type == IOMMU_DOMAIN_DMA)
-		iommu_setup_dma_ops(dev, IOVA_START_PFN << PAGE_SHIFT, U64_MAX);
-	else
-		set_dma_ops(dev, NULL);
+	iommu_setup_dma_ops(dev, 0, U64_MAX);
 }

 static void amd_iommu_release_device(struct device *dev)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index c62e19bed302..175f8eaeb5b3 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1322,7 +1322,9 @@ void iommu_setup_dma_ops(struct device *dev, u64 dma_base,
u64 dma_limit)
 	if (domain->type == IOMMU_DOMAIN_DMA) {
 		if (iommu_dma_init_domain(domain, dma_base, dma_limit, dev))
 			goto out_err;
-		dev->dma_ops = &iommu_dma_ops;
+		set_dma_ops(dev, &iommu_dma_ops);
+	} else {
+		set_dma_ops(dev, NULL);
 	}

 	return;
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 39a4e672b1c2..c6fe11d3624e 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5160,15 +5160,7 @@ static void intel_iommu_release_device(struct device
*dev)

 static void intel_iommu_probe_finalize(struct device *dev)
 {
-	dma_addr_t base = IOVA_START_PFN << VTD_PAGE_SHIFT;
-	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
-	struct dmar_domain *dmar_domain = to_dmar_domain(domain);
-
-	if (domain && domain->type == IOMMU_DOMAIN_DMA)
-		iommu_setup_dma_ops(dev, base,
-				    __DOMAIN_MAX_ADDR(dmar_domain->gaw));
-	else
-		set_dma_ops(dev, NULL);
+	iommu_setup_dma_ops(dev, 0, U64_MAX);
 }

 static void intel_iommu_get_resv_regions(struct device *device,
--
2.31.1