AMD IOMMU: fix lazy IO/TLB flushing in unmap path

Lazy flushing needs to take care of the unmap path too which is not yet
implemented and leads to stale IO/TLB entries. This is fixed by this
patch.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 38e88d40ab1091099656cf0c326c5f902d307b86..4755bbc7ae5b71796c364ff2c93e3a167d9730e2 100644 (file)
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -526,6 +526,9 @@ static void dma_ops_free_addresses(struct dma_ops_domain *dom,
 {
        address >>= PAGE_SHIFT;
        iommu_area_free(dom->bitmap, address, pages);
+
+       if (address + pages >= dom->next_bit)
+               dom->need_flush = true;
 }
 
 /****************************************************************************
@@ -981,8 +984,10 @@ static void __unmap_single(struct amd_iommu *iommu,
 
        dma_ops_free_addresses(dma_dom, dma_addr, pages);
 
-       if (amd_iommu_unmap_flush)
+       if (amd_iommu_unmap_flush || dma_dom->need_flush) {
                iommu_flush_pages(iommu, dma_dom->domain.id, dma_addr, size);
+               dma_dom->need_flush = false;
+       }
 }
 
 /*