iommu/amd: Optimize iommu_unmap_page for new fetch_pte interface

Now that fetch_pte returns the page-size of the pte, this
function can be optimized a lot.

Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 8 insertions, 24 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 24ef9e600289..c9ee444d8209 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1428,8 +1428,8 @@ static unsigned long iommu_unmap_page(struct protection_domain *dom,
                                       unsigned long bus_addr,
                                       unsigned long page_size)
 {
-        unsigned long long unmap_size, unmapped;
-        unsigned long pte_pgsize;
+        unsigned long long unmapped;
+        unsigned long unmap_size;
         u64 *pte;
 
         BUG_ON(!is_power_of_2(page_size));
@@ -1438,28 +1438,12 @@ static unsigned long iommu_unmap_page(struct protection_domain *dom,
 
         while (unmapped < page_size) {
 
-                pte = fetch_pte(dom, bus_addr, &pte_pgsize);
-
-                if (!pte) {
-                        /*
-                         * No PTE for this address
-                         * move forward in 4kb steps
-                         */
-                        unmap_size = PAGE_SIZE;
-                } else if (PM_PTE_LEVEL(*pte) == 0) {
-                        /* 4kb PTE found for this address */
-                        unmap_size = PAGE_SIZE;
-                        *pte       = 0ULL;
-                } else {
-                        int count, i;
-
-                        /* Large PTE found which maps this address */
-                        unmap_size = PTE_PAGE_SIZE(*pte);
-
-                        /* Only unmap from the first pte in the page */
-                        if ((unmap_size - 1) & bus_addr)
-                                break;
-                        count      = PAGE_SIZE_PTE_COUNT(unmap_size);
+                pte = fetch_pte(dom, bus_addr, &unmap_size);
+
+                if (pte) {
+                        int i, count;
+
+                        count = PAGE_SIZE_PTE_COUNT(unmap_size);
                         for (i = 0; i < count; i++)
                                 pte[i] = 0ULL;
                 }