Merge branch 'pci/iova-dma-ranges'

  - Add list of legal DMA address ranges to PCI host bridge (Srinath
    Mannam)

  - Reserve inaccessible DMA ranges so IOMMU doesn't allocate them (Srinath
    Mannam)

  - Parse iProc DT dma-ranges to learn what PCI devices can reach via DMA
    (Srinath Mannam)

* pci/iova-dma-ranges:
  PCI: iproc: Add sorted dma ranges resource entries to host bridge
  iommu/dma: Reserve IOVA for PCIe inaccessible DMA address
  PCI: Add dma_ranges window list

# Conflicts:
#	drivers/pci/probe.c

4 files changed, 78 insertions, 4 deletions

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 77aabe637a60..954ae11461a3 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -206,12 +206,13 @@ static int cookie_init_hw_msi_region(struct iommu_dma_cookie *cookie,
         return 0;
 }
 
-static void iova_reserve_pci_windows(struct pci_dev *dev,
+static int iova_reserve_pci_windows(struct pci_dev *dev,
                 struct iova_domain *iovad)
 {
         struct pci_host_bridge *bridge = pci_find_host_bridge(dev->bus);
         struct resource_entry *window;
         unsigned long lo, hi;
+        phys_addr_t start = 0, end;
 
         resource_list_for_each_entry(window, &bridge->windows) {
                 if (resource_type(window->res) != IORESOURCE_MEM)
@@ -221,6 +222,31 @@ static void iova_reserve_pci_windows(struct pci_dev *dev,
                 hi = iova_pfn(iovad, window->res->end - window->offset);
                 reserve_iova(iovad, lo, hi);
         }
+
+        /* Get reserved DMA windows from host bridge */
+        resource_list_for_each_entry(window, &bridge->dma_ranges) {
+                end = window->res->start - window->offset;
+resv_iova:
+                if (end > start) {
+                        lo = iova_pfn(iovad, start);
+                        hi = iova_pfn(iovad, end);
+                        reserve_iova(iovad, lo, hi);
+                } else {
+                        /* dma_ranges list should be sorted */
+                        dev_err(&dev->dev, "Failed to reserve IOVA\n");
+                        return -EINVAL;
+                }
+
+                start = window->res->end - window->offset + 1;
+                /* If window is last entry */
+                if (window->node.next == &bridge->dma_ranges &&
+                    end != ~(dma_addr_t)0) {
+                        end = ~(dma_addr_t)0;
+                        goto resv_iova;
+                }
+        }
+
+        return 0;
 }
 
 static int iova_reserve_iommu_regions(struct device *dev,
@@ -232,8 +258,11 @@ static int iova_reserve_iommu_regions(struct device *dev,
         LIST_HEAD(resv_regions);
         int ret = 0;
 
-        if (dev_is_pci(dev))
-                iova_reserve_pci_windows(to_pci_dev(dev), iovad);
+        if (dev_is_pci(dev)) {
+                ret = iova_reserve_pci_windows(to_pci_dev(dev), iovad);
+                if (ret)
+                        return ret;
+        }
 
         iommu_get_resv_regions(dev, &resv_regions);
         list_for_each_entry(region, &resv_regions, list) {
diff --git a/drivers/pci/controller/pcie-iproc.c b/drivers/pci/controller/pcie-iproc.c
index aa4768a2c0ca..e3ca46497470 100644
--- a/drivers/pci/controller/pcie-iproc.c
+++ b/drivers/pci/controller/pcie-iproc.c
@@ -1182,11 +1182,43 @@ err_ib:
         return ret;
 }
 
+static int iproc_pcie_add_dma_range(struct device *dev,
+                                    struct list_head *resources,
+                                    struct of_pci_range *range)
+{
+        struct resource *res;
+        struct resource_entry *entry, *tmp;
+        struct list_head *head = resources;
+
+        res = devm_kzalloc(dev, sizeof(struct resource), GFP_KERNEL);
+        if (!res)
+                return -ENOMEM;
+
+        resource_list_for_each_entry(tmp, resources) {
+                if (tmp->res->start < range->cpu_addr)
+                        head = &tmp->node;
+        }
+
+        res->start = range->cpu_addr;
+        res->end = res->start + range->size - 1;
+
+        entry = resource_list_create_entry(res, 0);
+        if (!entry)
+                return -ENOMEM;
+
+        entry->offset = res->start - range->cpu_addr;
+        resource_list_add(entry, head);
+
+        return 0;
+}
+
 static int iproc_pcie_map_dma_ranges(struct iproc_pcie *pcie)
 {
+        struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
         struct of_pci_range range;
         struct of_pci_range_parser parser;
         int ret;
+        LIST_HEAD(resources);
 
         /* Get the dma-ranges from DT */
         ret = of_pci_dma_range_parser_init(&parser, pcie->dev->of_node);
@@ -1194,13 +1226,23 @@ static int iproc_pcie_map_dma_ranges(struct iproc_pcie *pcie)
                 return ret;
 
         for_each_of_pci_range(&parser, &range) {
+                ret = iproc_pcie_add_dma_range(pcie->dev,
+                                               &resources,
+                                               &range);
+                if (ret)
+                        goto out;
                 /* Each range entry corresponds to an inbound mapping region */
                 ret = iproc_pcie_setup_ib(pcie, &range, IPROC_PCIE_IB_MAP_MEM);
                 if (ret)
-                        return ret;
+                        goto out;
         }
 
+        list_splice_init(&resources, &host->dma_ranges);
+
         return 0;
+out:
+        pci_free_resource_list(&resources);
+        return ret;
 }
 
 static int iproce_pcie_get_msi(struct iproc_pcie *pcie,
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 50cd9c17c08f..0dc42f0eb66d 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -589,6 +589,7 @@ static void pci_release_host_bridge_dev(struct device *dev)
 static void pci_init_host_bridge(struct pci_host_bridge *bridge)
 {
         INIT_LIST_HEAD(&bridge->windows);
+        INIT_LIST_HEAD(&bridge->dma_ranges);
 
         /*
          * We assume we can manage these PCIe features.  Some systems may
@@ -637,6 +638,7 @@ EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
 void pci_free_host_bridge(struct pci_host_bridge *bridge)
 {
         pci_free_resource_list(&bridge->windows);
+        pci_free_resource_list(&bridge->dma_ranges);
 
         kfree(bridge);
 }
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 6fc361a69e0c..87edbd23eddb 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -492,6 +492,7 @@ struct pci_host_bridge {
         void            *sysdata;
         int             busnr;
         struct list_head windows;       /* resource_entry */
+        struct list_head dma_ranges;    /* dma ranges resource list */
         u8 (*swizzle_irq)(struct pci_dev *, u8 *); /* Platform IRQ swizzler */
         int (*map_irq)(const struct pci_dev *, u8, u8);
         void (*release_fn)(struct pci_host_bridge *);