1 files changed, 42 insertions, 23 deletions

diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c
index e60a1a848de8..a1ad4cc423a7 100644
--- a/arch/x86_64/mm/init.c
+++ b/arch/x86_64/mm/init.c
@@ -318,32 +318,51 @@ void zap_low_mappings(void)
         flush_tlb_all();
 }
 
+/* Compute zone sizes for the DMA and DMA32 zones in a node. */
+__init void
+size_zones(unsigned long *z, unsigned long *h,
+           unsigned long start_pfn, unsigned long end_pfn)
+{
+        int i;
+        unsigned long w;
+
+        for (i = 0; i < MAX_NR_ZONES; i++)
+                z[i] = 0;
+
+        if (start_pfn < MAX_DMA_PFN)
+                z[ZONE_DMA] = MAX_DMA_PFN - start_pfn;
+        if (start_pfn < MAX_DMA32_PFN) {
+                unsigned long dma32_pfn = MAX_DMA32_PFN;
+                if (dma32_pfn > end_pfn)
+                        dma32_pfn = end_pfn;
+                z[ZONE_DMA32] = dma32_pfn - start_pfn;
+        }
+        z[ZONE_NORMAL] = end_pfn - start_pfn;
+
+        /* Remove lower zones from higher ones. */
+        w = 0;
+        for (i = 0; i < MAX_NR_ZONES; i++) {
+                if (z[i])
+                        z[i] -= w;
+                w += z[i];
+        }
+
+        /* Compute holes */
+        w = 0;
+        for (i = 0; i < MAX_NR_ZONES; i++) {
+                unsigned long s = w;
+                w += z[i];
+                h[i] = e820_hole_size(s, w);
+        }
+}
+
 #ifndef CONFIG_NUMA
 void __init paging_init(void)
 {
-        {
-                unsigned long zones_size[MAX_NR_ZONES];
-                unsigned long holes[MAX_NR_ZONES];
-                unsigned int max_dma;
-
-                memset(zones_size, 0, sizeof(zones_size));
-                memset(holes, 0, sizeof(holes));
-
-                max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
-
-                if (end_pfn < max_dma) {
-                        zones_size[ZONE_DMA] = end_pfn;
-                        holes[ZONE_DMA] = e820_hole_size(0, end_pfn);
-                } else {
-                        zones_size[ZONE_DMA] = max_dma;
-                        holes[ZONE_DMA] = e820_hole_size(0, max_dma);
-                        zones_size[ZONE_NORMAL] = end_pfn - max_dma;
-                        holes[ZONE_NORMAL] = e820_hole_size(max_dma, end_pfn);
-                }
-                free_area_init_node(0, NODE_DATA(0), zones_size,
-                        __pa(PAGE_OFFSET) >> PAGE_SHIFT, holes);
-        }
-        return;
+        unsigned long zones[MAX_NR_ZONES], holes[MAX_NR_ZONES];
+        size_zones(zones, holes, 0, end_pfn);
+        free_area_init_node(0, NODE_DATA(0), zones,
+                            __pa(PAGE_OFFSET) >> PAGE_SHIFT, holes);
 }
 #endif