5 files changed, 109 insertions, 17 deletions

diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h
index cfa3d5c3144a..9c9fe1b0bc4e 100644
--- a/arch/x86/include/asm/acpi.h
+++ b/arch/x86/include/asm/acpi.h
@@ -190,6 +190,7 @@ extern int x86_acpi_numa_init(void);
 #ifdef CONFIG_NUMA_EMU
 extern void acpi_fake_nodes(const struct bootnode *fake_nodes,
 				   int num_nodes);
+extern int acpi_emu_node_distance(int a, int b);
 #endif
 #endif /* CONFIG_ACPI_NUMA */
 
diff --git a/arch/x86/include/asm/numa_64.h b/arch/x86/include/asm/numa_64.h
index f42710bd3e73..5361c5947986 100644
--- a/arch/x86/include/asm/numa_64.h
+++ b/arch/x86/include/asm/numa_64.h
@@ -28,6 +28,7 @@ extern nodemask_t numa_nodes_parsed __initdata;
 
 extern int __cpuinit numa_cpu_node(int cpu);
 extern int __init numa_add_memblk(int nodeid, u64 start, u64 end);
+extern void __init numa_set_distance(int from, int to, int distance);
 
 #ifdef CONFIG_NUMA_EMU
 #define FAKE_NODE_MIN_SIZE	((u64)32 << 20)
diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index b101c17861f5..910a7084f7f2 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -138,7 +138,7 @@ extern unsigned long node_remap_size[];
 	.balance_interval	= 1,					\
 }
 
-#ifdef CONFIG_X86_64_ACPI_NUMA
+#ifdef CONFIG_X86_64
 extern int __node_distance(int, int);
 #define node_distance(a, b) __node_distance(a, b)
 #endif
diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c
index 8b1f178a866e..a3621f2953d6 100644
--- a/arch/x86/mm/numa_64.c
+++ b/arch/x86/mm/numa_64.c
@@ -45,6 +45,13 @@ static unsigned long __initdata nodemap_size;
 
 static struct numa_meminfo numa_meminfo __initdata;
 
+static int numa_distance_cnt;
+static u8 *numa_distance;
+
+#ifdef CONFIG_NUMA_EMU
+static bool numa_emu_dist;
+#endif
+
 /*
  * Given a shift value, try to populate memnodemap[]
  * Returns :
@@ -357,6 +364,92 @@ static void __init numa_nodemask_from_meminfo(nodemask_t *nodemask,
 }
 
 /*
+ * Reset distance table.  The current table is freed.  The next
+ * numa_set_distance() call will create a new one.
+ */
+static void __init numa_reset_distance(void)
+{
+	size_t size;
+
+	size = numa_distance_cnt * sizeof(numa_distance[0]);
+	memblock_x86_free_range(__pa(numa_distance),
+				__pa(numa_distance) + size);
+	numa_distance = NULL;
+	numa_distance_cnt = 0;
+}
+
+/*
+ * Set the distance between node @from to @to to @distance.  If distance
+ * table doesn't exist, one which is large enough to accomodate all the
+ * currently known nodes will be created.
+ */
+void __init numa_set_distance(int from, int to, int distance)
+{
+	if (!numa_distance) {
+		nodemask_t nodes_parsed;
+		size_t size;
+		int i, j, cnt = 0;
+		u64 phys;
+
+		/* size the new table and allocate it */
+		nodes_parsed = numa_nodes_parsed;
+		numa_nodemask_from_meminfo(&nodes_parsed, &numa_meminfo);
+
+		for_each_node_mask(i, nodes_parsed)
+			cnt = i;
+		size = ++cnt * sizeof(numa_distance[0]);
+
+		phys = memblock_find_in_range(0,
+					      (u64)max_pfn_mapped << PAGE_SHIFT,
+					      size, PAGE_SIZE);
+		if (phys == MEMBLOCK_ERROR) {
+			pr_warning("NUMA: Warning: can't allocate distance table!\n");
+			/* don't retry until explicitly reset */
+			numa_distance = (void *)1LU;
+			return;
+		}
+		memblock_x86_reserve_range(phys, phys + size, "NUMA DIST");
+
+		numa_distance = __va(phys);
+		numa_distance_cnt = cnt;
+
+		/* fill with the default distances */
+		for (i = 0; i < cnt; i++)
+			for (j = 0; j < cnt; j++)
+				numa_distance[i * cnt + j] = i == j ?
+					LOCAL_DISTANCE : REMOTE_DISTANCE;
+		printk(KERN_DEBUG "NUMA: Initialized distance table, cnt=%d\n", cnt);
+	}
+
+	if (from >= numa_distance_cnt || to >= numa_distance_cnt) {
+		printk_once(KERN_DEBUG "NUMA: Debug: distance out of bound, from=%d to=%d distance=%d\n",
+			    from, to, distance);
+		return;
+	}
+
+	if ((u8)distance != distance ||
+	    (from == to && distance != LOCAL_DISTANCE)) {
+		pr_warn_once("NUMA: Warning: invalid distance parameter, from=%d to=%d distance=%d\n",
+			     from, to, distance);
+		return;
+	}
+
+	numa_distance[from * numa_distance_cnt + to] = distance;
+}
+
+int __node_distance(int from, int to)
+{
+#if defined(CONFIG_ACPI_NUMA) && defined(CONFIG_NUMA_EMU)
+	if (numa_emu_dist)
+		return acpi_emu_node_distance(from, to);
+#endif
+	if (from >= numa_distance_cnt || to >= numa_distance_cnt)
+		return from == to ? LOCAL_DISTANCE : REMOTE_DISTANCE;
+	return numa_distance[from * numa_distance_cnt + to];
+}
+EXPORT_SYMBOL(__node_distance);
+
+/*
  * Sanity check to catch more bad NUMA configurations (they are amazingly
  * common).  Make sure the nodes cover all memory.
  */
@@ -826,6 +919,7 @@ static int __init numa_emulation(unsigned long start_pfn,
 	setup_physnodes(addr, max_addr);
 	fake_physnodes(acpi, amd, num_nodes);
 	numa_init_array();
+	numa_emu_dist = true;
 	return 0;
 }
 #endif /* CONFIG_NUMA_EMU */
@@ -869,6 +963,7 @@ void __init initmem_init(void)
 		nodes_clear(node_online_map);
 		memset(&numa_meminfo, 0, sizeof(numa_meminfo));
 		remove_all_active_ranges();
+		numa_reset_distance();
 
 		if (numa_init[i]() < 0)
 			continue;
diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
index 4f8e6cde9bf6..d2f53f35d86a 100644
--- a/arch/x86/mm/srat_64.c
+++ b/arch/x86/mm/srat_64.c
@@ -50,9 +50,16 @@ static __init inline int srat_disabled(void)
 /* Callback for SLIT parsing */
 void __init acpi_numa_slit_init(struct acpi_table_slit *slit)
 {
+	int i, j;
 	unsigned length;
 	unsigned long phys;
 
+	for (i = 0; i < slit->locality_count; i++)
+		for (j = 0; j < slit->locality_count; j++)
+			numa_set_distance(pxm_to_node(i), pxm_to_node(j),
+				slit->entry[slit->locality_count * i + j]);
+
+	/* acpi_slit is used only by emulation */
 	length = slit->header.length;
 	phys = memblock_find_in_range(0, max_pfn_mapped<<PAGE_SHIFT, length,
 		 PAGE_SIZE);
@@ -313,29 +320,17 @@ void __init acpi_fake_nodes(const struct bootnode *fake_nodes, int num_nodes)
 			node_set(i, numa_nodes_parsed);
 }
 
-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 */
-
-int __node_distance(int a, int b)
+int acpi_emu_node_distance(int a, int b)
 {
 	int index;
 
 	if (!acpi_slit)
-		return null_slit_node_compare(a, b) ? LOCAL_DISTANCE :
-						      REMOTE_DISTANCE;
+		return node_to_pxm(a) == node_to_pxm(b) ?
+			LOCAL_DISTANCE : REMOTE_DISTANCE;
 	index = acpi_slit->locality_count * node_to_pxm(a);
 	return acpi_slit->entry[index + node_to_pxm(b)];
 }
-
-EXPORT_SYMBOL(__node_distance);
+#endif /* CONFIG_NUMA_EMU */
 
 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || defined(CONFIG_ACPI_HOTPLUG_MEMORY)
 int memory_add_physaddr_to_nid(u64 start)