RFC x86: try to remove arch_get_ram_range

want to remove arch_get_ram_range, and use early_node_map instead.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>

Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 65d55056..a0484ad 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -298,7 +298,7 @@
 	unsigned long end_pfn;
 };
 
-static void __init add_highpages_work_fn(unsigned long start_pfn,
+static int __init add_highpages_work_fn(unsigned long start_pfn,
 					 unsigned long end_pfn, void *datax)
 {
 	int node_pfn;
@@ -311,7 +311,7 @@
 	final_start_pfn = max(start_pfn, data->start_pfn);
 	final_end_pfn = min(end_pfn, data->end_pfn);
 	if (final_start_pfn >= final_end_pfn)
-		return;
+		return 0;
 
 	for (node_pfn = final_start_pfn; node_pfn < final_end_pfn;
 	     node_pfn++) {
@@ -321,6 +321,8 @@
 		add_one_highpage_init(page, node_pfn);
 	}
 
+	return 0;
+
 }
 
 void __init add_highpages_with_active_regions(int nid, unsigned long start_pfn,
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 66c0fd2..bb06423 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -1637,12 +1637,43 @@
 }
 
 #ifdef CONFIG_DMAR_GFX_WA
-extern int arch_get_ram_range(int slot, u64 *addr, u64 *size);
+struct iommu_prepare_data {
+	struct pci_dev *pdev;
+	int ret;
+};
+
+static int __init iommu_prepare_work_fn(unsigned long start_pfn,
+					 unsigned long end_pfn, void *datax)
+{
+	struct iommu_prepare_data *data;
+
+	data = (struct iommu_prepare_data *)datax;
+
+	data->ret = iommu_prepare_identity_map(data->pdev,
+				start_pfn<<PAGE_SHIFT, end_pfn<<PAGE_SHIFT);
+	return data->ret;
+
+}
+
+static int __init iommu_prepare_with_active_regions(struct pci_dev *pdev)
+{
+	int nid;
+	struct iommu_prepare_data data;
+
+	data.pdev = pdev;
+	data.ret = 0;
+
+	for_each_online_node(nid) {
+		work_with_active_regions(nid, iommu_prepare_work_fn, &data);
+		if (data.ret)
+			return data.ret;
+	}
+	return data.ret;
+}
+
 static void __init iommu_prepare_gfx_mapping(void)
 {
 	struct pci_dev *pdev = NULL;
-	u64 base, size;
-	int slot;
 	int ret;
 
 	for_each_pci_dev(pdev) {
@@ -1651,17 +1682,9 @@
 			continue;
 		printk(KERN_INFO "IOMMU: gfx device %s 1-1 mapping\n",
 			pci_name(pdev));
-		slot = arch_get_ram_range(0, &base, &size);
-		while (slot >= 0) {
-			ret = iommu_prepare_identity_map(pdev,
-					base, base + size);
-			if (ret)
-				goto error;
-			slot = arch_get_ram_range(slot, &base, &size);
-		}
-		continue;
-error:
-		printk(KERN_ERR "IOMMU: mapping reserved region failed\n");
+		ret = iommu_prepare_with_active_regions(pdev);
+		if (ret)
+			printk(KERN_ERR "IOMMU: mapping reserved region failed\n");
 	}
 }
 #endif
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3d647b2..cf1cd3a 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1011,7 +1011,7 @@
 extern unsigned long find_max_pfn_with_active_regions(void);
 extern void free_bootmem_with_active_regions(int nid,
 						unsigned long max_low_pfn);
-typedef void (*work_fn_t)(unsigned long, unsigned long, void *);
+typedef int (*work_fn_t)(unsigned long, unsigned long, void *);
 extern void work_with_active_regions(int nid, work_fn_t work_fn, void *data);
 extern void sparse_memory_present_with_active_regions(int nid);
 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 41c6e3a..e25b6b2 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2932,10 +2932,14 @@
 void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data)
 {
 	int i;
+	int ret;
 
-	for_each_active_range_index_in_nid(i, nid)
-		work_fn(early_node_map[i].start_pfn, early_node_map[i].end_pfn,
-			data);
+	for_each_active_range_index_in_nid(i, nid) {
+		ret = work_fn(early_node_map[i].start_pfn,
+			      early_node_map[i].end_pfn, data);
+		if (ret)
+			break;
+	}
 }
 /**
  * sparse_memory_present_with_active_regions - Call memory_present for each active range