iommu: Introduce iotlb_sync_map callback

Introduce iotlb_sync_map() callback that is invoked in the end of
iommu_map(). This new callback allows IOMMU drivers to avoid syncing
after mapping of each contiguous chunk and sync only when the whole
mapping is completed, optimizing performance of the mapping operation.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3ed4db3343416ee35b136c13076fdd49da395d15..ed0e63f2cd9b962de903d2da817b32e1c690a4ba 100644 (file)
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1585,13 +1585,14 @@ static size_t iommu_pgsize(struct iommu_domain *domain,
 int iommu_map(struct iommu_domain *domain, unsigned long iova,
              phys_addr_t paddr, size_t size, int prot)
 {
+       const struct iommu_ops *ops = domain->ops;
        unsigned long orig_iova = iova;
        unsigned int min_pagesz;
        size_t orig_size = size;
        phys_addr_t orig_paddr = paddr;
        int ret = 0;
 
-       if (unlikely(domain->ops->map == NULL ||
+       if (unlikely(ops->map == NULL ||
                     domain->pgsize_bitmap == 0UL))
                return -ENODEV;
 
@@ -1620,7 +1621,7 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova,
                pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx\n",
                         iova, &paddr, pgsize);
 
-               ret = domain->ops->map(domain, iova, paddr, pgsize, prot);
+               ret = ops->map(domain, iova, paddr, pgsize, prot);
                if (ret)
                        break;
 
@@ -1629,6 +1630,9 @@ int iommu_map(struct iommu_domain *domain, unsigned long iova,
                size -= pgsize;
        }
 
+       if (ops->iotlb_sync_map)
+               ops->iotlb_sync_map(domain);
+
        /* unroll mapping in case something went wrong */
        if (ret)
                iommu_unmap(domain, orig_iova, orig_size - size);

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index e90da6b6f3d1b91d431d4f194e70c3cf872b3493..477ef47c357c0553c339f8ffc05eff91b4862185 100644 (file)
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -201,6 +201,7 @@ struct iommu_ops {
        void (*flush_iotlb_all)(struct iommu_domain *domain);
        void (*iotlb_range_add)(struct iommu_domain *domain,
                                unsigned long iova, size_t size);
+       void (*iotlb_sync_map)(struct iommu_domain *domain);
        void (*iotlb_sync)(struct iommu_domain *domain);
        phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova);
        int (*add_device)(struct device *dev);