amd-iommu: handle page table allocation failures in dma_ops code

The code will be required when the aperture size increases dynamically
in the extended address allocator.

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

1 files changed, 18 insertions, 2 deletions

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index ded79f7747c5..a467addb44b7 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1193,6 +1193,8 @@ static dma_addr_t dma_ops_domain_map(struct amd_iommu *iommu,
         paddr &= PAGE_MASK;
 
         pte  = dma_ops_get_pte(dom, address);
+        if (!pte)
+                return bad_dma_address;
 
         __pte = paddr | IOMMU_PTE_P | IOMMU_PTE_FC;
 
@@ -1248,7 +1250,7 @@ static dma_addr_t __map_single(struct device *dev,
                                u64 dma_mask)
 {
         dma_addr_t offset = paddr & ~PAGE_MASK;
-        dma_addr_t address, start;
+        dma_addr_t address, start, ret;
         unsigned int pages;
         unsigned long align_mask = 0;
         int i;
@@ -1271,7 +1273,10 @@ static dma_addr_t __map_single(struct device *dev,
 
         start = address;
         for (i = 0; i < pages; ++i) {
-                dma_ops_domain_map(iommu, dma_dom, start, paddr, dir);
+                ret = dma_ops_domain_map(iommu, dma_dom, start, paddr, dir);
+                if (ret == bad_dma_address)
+                        goto out_unmap;
+
                 paddr += PAGE_SIZE;
                 start += PAGE_SIZE;
         }
@@ -1287,6 +1292,17 @@ static dma_addr_t __map_single(struct device *dev,
 
 out:
         return address;
+
+out_unmap:
+
+        for (--i; i >= 0; --i) {
+                start -= PAGE_SIZE;
+                dma_ops_domain_unmap(iommu, dma_dom, start);
+        }
+
+        dma_ops_free_addresses(dma_dom, address, pages);
+
+        return bad_dma_address;
 }
 
 /*