3 files changed, 83 insertions, 33 deletions

diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index 947b5c417e83..122c299e90c8 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -125,7 +125,6 @@ int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc,
 
 /* generic pci stuff */
 #include <asm-generic/pci.h>
-#define PCIBIOS_MAX_MEM_32 0xffffffff
 
 #ifdef CONFIG_NUMA
 /* Returns the node based on pci bus */
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 6f2f47a7b6c6..c30baae929f4 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -98,41 +98,52 @@ void pci_bus_remove_resources(struct pci_bus *bus)
         }
 }
 
-/**
- * pci_bus_alloc_resource - allocate a resource from a parent bus
- * @bus: PCI bus
- * @res: resource to allocate
- * @size: size of resource to allocate
- * @align: alignment of resource to allocate
- * @min: minimum /proc/iomem address to allocate
- * @type_mask: IORESOURCE_* type flags
- * @alignf: resource alignment function
- * @alignf_data: data argument for resource alignment function
- *
- * Given the PCI bus a device resides on, the size, minimum address,
- * alignment and type, try to find an acceptable resource allocation
- * for a specific device resource.
+static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+static struct pci_bus_region pci_64_bit = {0,
+                                (dma_addr_t) 0xffffffffffffffffULL};
+#endif
+
+/*
+ * @res contains CPU addresses.  Clip it so the corresponding bus addresses
+ * on @bus are entirely within @region.  This is used to control the bus
+ * addresses of resources we allocate, e.g., we may need a resource that
+ * can be mapped by a 32-bit BAR.
  */
-int
-pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
+static void pci_clip_resource_to_region(struct pci_bus *bus,
+                                        struct resource *res,
+                                        struct pci_bus_region *region)
+{
+        struct pci_bus_region r;
+
+        pcibios_resource_to_bus(bus, &r, res);
+        if (r.start < region->start)
+                r.start = region->start;
+        if (r.end > region->end)
+                r.end = region->end;
+
+        if (r.end < r.start)
+                res->end = res->start - 1;
+        else
+                pcibios_bus_to_resource(bus, res, &r);
+}
+
+static int pci_bus_alloc_from_region(struct pci_bus *bus, struct resource *res,
                 resource_size_t size, resource_size_t align,
                 resource_size_t min, unsigned int type_mask,
                 resource_size_t (*alignf)(void *,
                                           const struct resource *,
                                           resource_size_t,
                                           resource_size_t),
-                void *alignf_data)
+                void *alignf_data,
+                struct pci_bus_region *region)
 {
-        int i, ret = -ENOMEM;
-        struct resource *r;
-        resource_size_t max = -1;
+        int i, ret;
+        struct resource *r, avail;
+        resource_size_t max;
 
         type_mask |= IORESOURCE_IO | IORESOURCE_MEM;
 
-        /* don't allocate too high if the pref mem doesn't support 64bit*/
-        if (!(res->flags & IORESOURCE_MEM_64))
-                max = PCIBIOS_MAX_MEM_32;
-
         pci_bus_for_each_resource(bus, r, i) {
                 if (!r)
                         continue;
@@ -147,22 +158,66 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
                     !(res->flags & IORESOURCE_PREFETCH))
                         continue;
 
+                avail = *r;
+                pci_clip_resource_to_region(bus, &avail, region);
+                if (!resource_size(&avail))
+                        continue;
+
                 /*
                  * "min" is typically PCIBIOS_MIN_IO or PCIBIOS_MIN_MEM to
                  * protect badly documented motherboard resources, but if
                  * this is an already-configured bridge window, its start
                  * overrides "min".
                  */
-                if (r->start)
-                        min = r->start;
+                if (avail.start)
+                        min = avail.start;
+
+                max = avail.end;
 
                 /* Ok, try it out.. */
                 ret = allocate_resource(r, res, size, min, max,
                                         align, alignf, alignf_data);
                 if (ret == 0)
-                        break;
+                        return 0;
         }
-        return ret;
+        return -ENOMEM;
+}
+
+/**
+ * pci_bus_alloc_resource - allocate a resource from a parent bus
+ * @bus: PCI bus
+ * @res: resource to allocate
+ * @size: size of resource to allocate
+ * @align: alignment of resource to allocate
+ * @min: minimum /proc/iomem address to allocate
+ * @type_mask: IORESOURCE_* type flags
+ * @alignf: resource alignment function
+ * @alignf_data: data argument for resource alignment function
+ *
+ * Given the PCI bus a device resides on, the size, minimum address,
+ * alignment and type, try to find an acceptable resource allocation
+ * for a specific device resource.
+ */
+int
+pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
+                resource_size_t size, resource_size_t align,
+                resource_size_t min, unsigned int type_mask,
+                resource_size_t (*alignf)(void *,
+                                          const struct resource *,
+                                          resource_size_t,
+                                          resource_size_t),
+                void *alignf_data)
+{
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+        if (res->flags & IORESOURCE_MEM_64)
+                return pci_bus_alloc_from_region(bus, res, size, align, min,
+                                                 type_mask, alignf, alignf_data,
+                                                 &pci_64_bit);
+#endif
+
+        return pci_bus_alloc_from_region(bus, res, size, align, min,
+                                         type_mask, alignf, alignf_data,
+                                         &pci_32_bit);
 }
 
 void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 966b286b5d53..095eb44fcbb6 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -1493,10 +1493,6 @@ static inline struct pci_dev *pci_dev_get(struct pci_dev *dev)
 
 #include <asm/pci.h>
 
-#ifndef PCIBIOS_MAX_MEM_32
-#define PCIBIOS_MAX_MEM_32 (-1)
-#endif
-
 /* these helpers provide future and backwards compatibility
  * for accessing popular PCI BAR info */
 #define pci_resource_start(dev, bar)    ((dev)->resource[(bar)].start)