1 files changed, 89 insertions, 8 deletions

diff --git a/arch/x86_64/mm/srat.c b/arch/x86_64/mm/srat.c
index 1e76bb0a7277..acdf03e19146 100644
--- a/arch/x86_64/mm/srat.c
+++ b/arch/x86_64/mm/srat.c
@@ -106,9 +106,9 @@ static __init int slit_valid(struct acpi_table_slit *slit)
 		for (j = 0; j < d; j++)  {
 			u8 val = slit->entry[d*i + j];
 			if (i == j) {
-				if (val != 10)
+				if (val != LOCAL_DISTANCE)
 					return 0;
-			} else if (val <= 10)
+			} else if (val <= LOCAL_DISTANCE)
 				return 0;
 		}
 	}
@@ -350,7 +350,7 @@ acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
 
 /* Sanity check to catch more bad SRATs (they are amazingly common).
    Make sure the PXMs cover all memory. */
-static int nodes_cover_memory(void)
+static int __init nodes_cover_memory(const struct bootnode *nodes)
 {
 	int i;
 	unsigned long pxmram, e820ram;
@@ -394,6 +394,9 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end)
 {
 	int i;
 
+	if (acpi_numa <= 0)
+		return -1;
+
 	/* First clean up the node list */
 	for (i = 0; i < MAX_NUMNODES; i++) {
 		cutoff_node(i, start, end);
@@ -403,10 +406,7 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end)
 		}
 	}
 
-	if (acpi_numa <= 0)
-		return -1;
-
-	if (!nodes_cover_memory()) {
+	if (!nodes_cover_memory(nodes)) {
 		bad_srat();
 		return -1;
 	}
@@ -440,6 +440,86 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end)
 	return 0;
 }
 
+#ifdef CONFIG_NUMA_EMU
+static int __init find_node_by_addr(unsigned long addr)
+{
+	int ret = NUMA_NO_NODE;
+	int i;
+
+	for_each_node_mask(i, nodes_parsed) {
+		/*
+		 * Find the real node that this emulated node appears on.  For
+		 * the sake of simplicity, we only use a real node's starting
+		 * address to determine which emulated node it appears on.
+		 */
+		if (addr >= nodes[i].start && addr < nodes[i].end) {
+			ret = i;
+			break;
+		}
+	}
+	return i;
+}
+
+/*
+ * In NUMA emulation, we need to setup proximity domain (_PXM) to node ID
+ * mappings that respect the real ACPI topology but reflect our emulated
+ * environment.  For each emulated node, we find which real node it appears on
+ * and create PXM to NID mappings for those fake nodes which mirror that
+ * locality.  SLIT will now represent the correct distances between emulated
+ * nodes as a result of the real topology.
+ */
+void __init acpi_fake_nodes(const struct bootnode *fake_nodes, int num_nodes)
+{
+	int i, j;
+	int fake_node_to_pxm_map[MAX_NUMNODES] = {
+		[0 ... MAX_NUMNODES-1] = PXM_INVAL
+	};
+	unsigned char fake_apicid_to_node[MAX_LOCAL_APIC] = {
+		[0 ... MAX_LOCAL_APIC-1] = NUMA_NO_NODE
+	};
+
+	printk(KERN_INFO "Faking PXM affinity for fake nodes on real "
+			 "topology.\n");
+	for (i = 0; i < num_nodes; i++) {
+		int nid, pxm;
+
+		nid = find_node_by_addr(fake_nodes[i].start);
+		if (nid == NUMA_NO_NODE)
+			continue;
+		pxm = node_to_pxm(nid);
+		if (pxm == PXM_INVAL)
+			continue;
+		fake_node_to_pxm_map[i] = pxm;
+		/*
+		 * For each apicid_to_node mapping that exists for this real
+		 * node, it must now point to the fake node ID.
+		 */
+		for (j = 0; j < MAX_LOCAL_APIC; j++)
+			if (apicid_to_node[j] == nid)
+				fake_apicid_to_node[j] = i;
+	}
+	for (i = 0; i < num_nodes; i++)
+		__acpi_map_pxm_to_node(fake_node_to_pxm_map[i], i);
+	memcpy(apicid_to_node, fake_apicid_to_node, sizeof(apicid_to_node));
+
+	nodes_clear(nodes_parsed);
+	for (i = 0; i < num_nodes; i++)
+		if (fake_nodes[i].start != fake_nodes[i].end)
+			node_set(i, nodes_parsed);
+	WARN_ON(!nodes_cover_memory(fake_nodes));
+}
+
+static int null_slit_node_compare(int a, int b)
+{
+	return node_to_pxm(a) == node_to_pxm(b);
+}
+#else
+static int null_slit_node_compare(int a, int b)
+{
+	return a == b;
+}
+#endif /* CONFIG_NUMA_EMU */
+
 void __init srat_reserve_add_area(int nodeid)
 {
 	if (found_add_area && nodes_add[nodeid].end) {
@@ -464,7 +544,8 @@ int __node_distance(int a, int b)
 	int index;
 
 	if (!acpi_slit)
-		return a == b ? 10 : 20;
+		return null_slit_node_compare(a, b) ? LOCAL_DISTANCE :
+						      REMOTE_DISTANCE;
 	index = acpi_slit->locality_count * node_to_pxm(a);
 	return acpi_slit->entry[index + node_to_pxm(b)];
 }