[PATCH 5/5] iommu/arm-smmu: Hook up map_sg()

Isaac J. Manjarres
2021-01-09T01:51:50Z

Now that everything is in place for iommu_map_sg() to defer
mapping a scatter-gather list to the io-pgtable layer, implement
the map_sg() callback in the SMMU driver, so that iommu_map_sg()
can invoke it with the entire scatter-gather list that will be
mapped.

Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org>
---
drivers/iommu/arm/arm-smmu/arm-smmu.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index d8c6bfd..52acc68 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -1208,6 +1208,24 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
return ret;
}

+static int arm_smmu_map_sg(struct iommu_domain *domain, unsigned long iova,
+ struct scatterlist *sg, unsigned int nents, int prot,
+ gfp_t gfp, size_t *mapped)
+{
+ struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
+ struct arm_smmu_device *smmu = to_smmu_domain(domain)->smmu;
+ int ret;
+
+ if (!ops)
+ return -ENODEV;
+
+ arm_smmu_rpm_get(smmu);
+ ret = ops->map_sg(ops, iova, sg, nents, prot, gfp, mapped);
+ arm_smmu_rpm_put(smmu);
+
+ return ret;
+}
+
static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size, struct iommu_iotlb_gather *gather)
{
@@ -1624,6 +1642,7 @@ static struct iommu_ops arm_smmu_ops = {
.domain_free = arm_smmu_domain_free,
.attach_dev = arm_smmu_attach_dev,
.map = arm_smmu_map,
+ .map_sg = arm_smmu_map_sg,
.unmap = arm_smmu_unmap,
.flush_iotlb_all = arm_smmu_flush_iotlb_all,
.iotlb_sync = arm_smmu_iotlb_sync,