iommu/amd: Do not flush Device Table in iommu_map_page()

The flush of the Device Table Entries for the domain has already
happened in increase_address_space(), if necessary. Do no flush them
again in iommu_map_page().

Signed-off-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Qian Cai <cai@lca.pw>
Link: https://lore.kernel.org/r/20200504125413.16798-6-joro@8bytes.org
Signed-off-by: Joerg Roedel <jroedel@suse.de>

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 2ae1daa..1dc3718 100644 (file)
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1446,15 +1446,18 @@ static bool increase_address_space(struct protection_domain *domain,
 {
        struct domain_pgtable pgtable;
        unsigned long flags;
-       bool ret = false;
+       bool ret = true;
        u64 *pte, root;
 
        spin_lock_irqsave(&domain->lock, flags);
 
        amd_iommu_domain_get_pgtable(domain, &pgtable);
 
-       if (address <= PM_LEVEL_SIZE(pgtable.mode) ||
-           WARN_ON_ONCE(pgtable.mode == PAGE_MODE_6_LEVEL))
+       if (address <= PM_LEVEL_SIZE(pgtable.mode))
+               goto out;
+
+       ret = false;
+       if (WARN_ON_ONCE(pgtable.mode == PAGE_MODE_6_LEVEL))
                goto out;
 
        pte = (void *)get_zeroed_page(gfp);
@@ -1499,19 +1502,15 @@ static u64 *alloc_pte(struct protection_domain *domain,
        amd_iommu_domain_get_pgtable(domain, &pgtable);
 
        while (address > PM_LEVEL_SIZE(pgtable.mode)) {
-               bool upd = increase_address_space(domain, address, gfp);
-
-               /* Read new values to check if update was successful */
-               amd_iommu_domain_get_pgtable(domain, &pgtable);
-
                /*
                 * Return an error if there is no memory to update the
                 * page-table.
                 */
-               if (!upd && (address > PM_LEVEL_SIZE(pgtable.mode)))
+               if (!increase_address_space(domain, address, gfp))
                        return NULL;
 
-               *updated = *updated || upd;
+               /* Read new values to check if update was successful */
+               amd_iommu_domain_get_pgtable(domain, &pgtable);
        }
 
 
@@ -1719,7 +1718,13 @@ out:
                unsigned long flags;
 
                spin_lock_irqsave(&dom->lock, flags);
-               update_domain(dom);
+               /*
+                * Flush domain TLB(s) and wait for completion. Any Device-Table
+                * Updates and flushing already happened in
+                * increase_address_space().
+                */
+               domain_flush_tlb_pde(dom);
+               domain_flush_complete(dom);
                spin_unlock_irqrestore(&dom->lock, flags);
        }