iommu/amd: Create a list of reserved iova addresses

Put the MSI-range, the HT-range and the MMIO ranges of PCI
devices into that range, so that these addresses are not
allocated for DMA.

Copy this address list into every created dma_ops_domain.

Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 69 insertions, 0 deletions

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index e7825b25c62f..1bb59ae2d586 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -63,6 +63,12 @@
 #define IOVA_PFN(addr)          ((addr) >> PAGE_SHIFT)
 #define DMA_32BIT_PFN           IOVA_PFN(DMA_BIT_MASK(32))
 
+/* Reserved IOVA ranges */
+#define MSI_RANGE_START         (0xfee00000)
+#define MSI_RANGE_END           (0xfeefffff)
+#define HT_RANGE_START          (0xfd00000000ULL)
+#define HT_RANGE_END            (0xffffffffffULL)
+
 /*
  * This bitmap is used to advertise the page sizes our hardware support
  * to the IOMMU core, which will then use this information to split
@@ -169,6 +175,9 @@ struct dma_ops_domain {
         struct iova_domain iovad;
 };
 
+static struct iova_domain reserved_iova_ranges;
+static struct lock_class_key reserved_rbtree_key;
+
 /****************************************************************************
  *
  * Helper functions
@@ -2058,6 +2067,9 @@ static struct dma_ops_domain *dma_ops_domain_alloc(void)
         init_iova_domain(&dma_dom->iovad, PAGE_SIZE,
                          IOVA_START_PFN, DMA_32BIT_PFN);
 
+        /* Initialize reserved ranges */
+        copy_reserved_iova(&reserved_iova_ranges, &dma_dom->iovad);
+
         return dma_dom;
 
 free_dma_dom:
@@ -2963,6 +2975,59 @@ static struct dma_map_ops amd_iommu_dma_ops = {
         .set_dma_mask   = set_dma_mask,
 };
 
+static int init_reserved_iova_ranges(void)
+{
+        struct pci_dev *pdev = NULL;
+        struct iova *val;
+
+        init_iova_domain(&reserved_iova_ranges, PAGE_SIZE,
+                         IOVA_START_PFN, DMA_32BIT_PFN);
+
+        lockdep_set_class(&reserved_iova_ranges.iova_rbtree_lock,
+                          &reserved_rbtree_key);
+
+        /* MSI memory range */
+        val = reserve_iova(&reserved_iova_ranges,
+                           IOVA_PFN(MSI_RANGE_START), IOVA_PFN(MSI_RANGE_END));
+        if (!val) {
+                pr_err("Reserving MSI range failed\n");
+                return -ENOMEM;
+        }
+
+        /* HT memory range */
+        val = reserve_iova(&reserved_iova_ranges,
+                           IOVA_PFN(HT_RANGE_START), IOVA_PFN(HT_RANGE_END));
+        if (!val) {
+                pr_err("Reserving HT range failed\n");
+                return -ENOMEM;
+        }
+
+        /*
+         * Memory used for PCI resources
+         * FIXME: Check whether we can reserve the PCI-hole completly
+         */
+        for_each_pci_dev(pdev) {
+                int i;
+
+                for (i = 0; i < PCI_NUM_RESOURCES; ++i) {
+                        struct resource *r = &pdev->resource[i];
+
+                        if (!(r->flags & IORESOURCE_MEM))
+                                continue;
+
+                        val = reserve_iova(&reserved_iova_ranges,
+                                           IOVA_PFN(r->start),
+                                           IOVA_PFN(r->end));
+                        if (!val) {
+                                pr_err("Reserve pci-resource range failed\n");
+                                return -ENOMEM;
+                        }
+                }
+        }
+
+        return 0;
+}
+
 int __init amd_iommu_init_api(void)
 {
         int ret, err = 0;
@@ -2971,6 +3036,10 @@ int __init amd_iommu_init_api(void)
         if (ret)
                 return ret;
 
+        ret = init_reserved_iova_ranges();
+        if (ret)
+                return ret;
+
         err = bus_set_iommu(&pci_bus_type, &amd_iommu_ops);
         if (err)
                 return err;