AMD IOMMU: add checks for dma_ops domain to dma_ops functions

Impact: detect when a driver uses a device assigned otherwise

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

1 files changed, 35 insertions, 6 deletions

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index bb28e2cda711..5c465c91150e 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -792,6 +792,15 @@ free_dma_dom:
 }
 
 /*
+ * little helper function to check whether a given protection domain is a
+ * dma_ops domain
+ */
+static bool dma_ops_domain(struct protection_domain *domain)
+{
+        return domain->flags & PD_DMA_OPS_MASK;
+}
+
+/*
  * Find out the protection domain structure for a given PCI device. This
  * will give us the pointer to the page table root for example.
  */
@@ -1096,6 +1105,9 @@ static dma_addr_t map_single(struct device *dev, phys_addr_t paddr,
                 /* device not handled by any AMD IOMMU */
                 return (dma_addr_t)paddr;
 
+        if (!dma_ops_domain(domain))
+                return bad_dma_address;
+
         spin_lock_irqsave(&domain->lock, flags);
         addr = __map_single(dev, iommu, domain->priv, paddr, size, dir, false,
                             dma_mask);
@@ -1126,6 +1138,9 @@ static void unmap_single(struct device *dev, dma_addr_t dma_addr,
                 /* device not handled by any AMD IOMMU */
                 return;
 
+        if (!dma_ops_domain(domain))
+                return;
+
         spin_lock_irqsave(&domain->lock, flags);
 
         __unmap_single(iommu, domain->priv, dma_addr, size, dir);
@@ -1180,6 +1195,9 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
         if (!iommu || !domain)
                 return map_sg_no_iommu(dev, sglist, nelems, dir);
 
+        if (!dma_ops_domain(domain))
+                return 0;
+
         spin_lock_irqsave(&domain->lock, flags);
 
         for_each_sg(sglist, s, nelems, i) {
@@ -1233,6 +1251,9 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
             !get_device_resources(dev, &iommu, &domain, &devid))
                 return;
 
+        if (!dma_ops_domain(domain))
+                return;
+
         spin_lock_irqsave(&domain->lock, flags);
 
         for_each_sg(sglist, s, nelems, i) {
@@ -1278,6 +1299,9 @@ static void *alloc_coherent(struct device *dev, size_t size,
                 return virt_addr;
         }
 
+        if (!dma_ops_domain(domain))
+                goto out_free;
+
         if (!dma_mask)
                 dma_mask = *dev->dma_mask;
 
@@ -1286,18 +1310,20 @@ static void *alloc_coherent(struct device *dev, size_t size,
         *dma_addr = __map_single(dev, iommu, domain->priv, paddr,
                                  size, DMA_BIDIRECTIONAL, true, dma_mask);
 
-        if (*dma_addr == bad_dma_address) {
-                free_pages((unsigned long)virt_addr, get_order(size));
-                virt_addr = NULL;
-                goto out;
-        }
+        if (*dma_addr == bad_dma_address)
+                goto out_free;
 
         iommu_completion_wait(iommu);
 
-out:
         spin_unlock_irqrestore(&domain->lock, flags);
 
         return virt_addr;
+
+out_free:
+
+        free_pages((unsigned long)virt_addr, get_order(size));
+
+        return NULL;
 }
 
 /*
@@ -1319,6 +1345,9 @@ static void free_coherent(struct device *dev, size_t size,
         if (!iommu || !domain)
                 goto free_mem;
 
+        if (!dma_ops_domain(domain))
+                goto free_mem;
+
         spin_lock_irqsave(&domain->lock, flags);
 
         __unmap_single(iommu, domain->priv, dma_addr, size, DMA_BIDIRECTIONAL);