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authorPaul Mackerras <paulus@samba.org>2005-10-10 21:58:35 +1000
committerPaul Mackerras <paulus@samba.org>2005-10-10 21:58:35 +1000
commitab1f9dac6eea25ee59e4c8e1cf0b7476afbbfe07 (patch)
tree03577652197b5e58c348ede3c474bc8dd47e046c /arch/powerpc/mm/numa.c
parent70d64ceaa1a84d2502405422a4dfd3f87786a347 (diff)
downloadlinux-ab1f9dac6eea25ee59e4c8e1cf0b7476afbbfe07.tar.gz
powerpc: Merge arch/ppc64/mm to arch/powerpc/mm
This moves the remaining files in arch/ppc64/mm to arch/powerpc/mm,
and arranges that we use them when compiling with ARCH=ppc64.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/mm/numa.c')
-rw-r--r--arch/powerpc/mm/numa.c779
1 files changed, 779 insertions, 0 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
new file mode 100644
index 000000000000..cb864b8f2750
--- /dev/null
+++ b/arch/powerpc/mm/numa.c
@@ -0,0 +1,779 @@
+/*
+ * pSeries NUMA support
+ *
+ * Copyright (C) 2002 Anton Blanchard <anton@au.ibm.com>, IBM
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <linux/threads.h>
+#include <linux/bootmem.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/module.h>
+#include <linux/nodemask.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
+#include <asm/lmb.h>
+#include <asm/machdep.h>
+#include <asm/abs_addr.h>
+
+static int numa_enabled = 1;
+
+static int numa_debug;
+#define dbg(args...) if (numa_debug) { printk(KERN_INFO args); }
+
+#ifdef DEBUG_NUMA
+#define ARRAY_INITIALISER -1
+#else
+#define ARRAY_INITIALISER 0
+#endif
+
+int numa_cpu_lookup_table[NR_CPUS] = { [ 0 ... (NR_CPUS - 1)] =
+	ARRAY_INITIALISER};
+char *numa_memory_lookup_table;
+cpumask_t numa_cpumask_lookup_table[MAX_NUMNODES];
+int nr_cpus_in_node[MAX_NUMNODES] = { [0 ... (MAX_NUMNODES -1)] = 0};
+
+struct pglist_data *node_data[MAX_NUMNODES];
+bootmem_data_t __initdata plat_node_bdata[MAX_NUMNODES];
+static int min_common_depth;
+
+/*
+ * We need somewhere to store start/span for each node until we have
+ * allocated the real node_data structures.
+ */
+static struct {
+	unsigned long node_start_pfn;
+	unsigned long node_end_pfn;
+	unsigned long node_present_pages;
+} init_node_data[MAX_NUMNODES] __initdata;
+
+EXPORT_SYMBOL(node_data);
+EXPORT_SYMBOL(numa_cpu_lookup_table);
+EXPORT_SYMBOL(numa_memory_lookup_table);
+EXPORT_SYMBOL(numa_cpumask_lookup_table);
+EXPORT_SYMBOL(nr_cpus_in_node);
+
+static inline void map_cpu_to_node(int cpu, int node)
+{
+	numa_cpu_lookup_table[cpu] = node;
+	if (!(cpu_isset(cpu, numa_cpumask_lookup_table[node]))) {
+		cpu_set(cpu, numa_cpumask_lookup_table[node]);
+		nr_cpus_in_node[node]++;
+	}
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static void unmap_cpu_from_node(unsigned long cpu)
+{
+	int node = numa_cpu_lookup_table[cpu];
+
+	dbg("removing cpu %lu from node %d\n", cpu, node);
+
+	if (cpu_isset(cpu, numa_cpumask_lookup_table[node])) {
+		cpu_clear(cpu, numa_cpumask_lookup_table[node]);
+		nr_cpus_in_node[node]--;
+	} else {
+		printk(KERN_ERR "WARNING: cpu %lu not found in node %d\n",
+		       cpu, node);
+	}
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+static struct device_node * __devinit find_cpu_node(unsigned int cpu)
+{
+	unsigned int hw_cpuid = get_hard_smp_processor_id(cpu);
+	struct device_node *cpu_node = NULL;
+	unsigned int *interrupt_server, *reg;
+	int len;
+
+	while ((cpu_node = of_find_node_by_type(cpu_node, "cpu")) != NULL) {
+		/* Try interrupt server first */
+		interrupt_server = (unsigned int *)get_property(cpu_node,
+					"ibm,ppc-interrupt-server#s", &len);
+
+		len = len / sizeof(u32);
+
+		if (interrupt_server && (len > 0)) {
+			while (len--) {
+				if (interrupt_server[len] == hw_cpuid)
+					return cpu_node;
+			}
+		} else {
+			reg = (unsigned int *)get_property(cpu_node,
+							   "reg", &len);
+			if (reg && (len > 0) && (reg[0] == hw_cpuid))
+				return cpu_node;
+		}
+	}
+
+	return NULL;
+}
+
+/* must hold reference to node during call */
+static int *of_get_associativity(struct device_node *dev)
+{
+	return (unsigned int *)get_property(dev, "ibm,associativity", NULL);
+}
+
+static int of_node_numa_domain(struct device_node *device)
+{
+	int numa_domain;
+	unsigned int *tmp;
+
+	if (min_common_depth == -1)
+		return 0;
+
+	tmp = of_get_associativity(device);
+	if (tmp && (tmp[0] >= min_common_depth)) {
+		numa_domain = tmp[min_common_depth];
+	} else {
+		dbg("WARNING: no NUMA information for %s\n",
+		    device->full_name);
+		numa_domain = 0;
+	}
+	return numa_domain;
+}
+
+/*
+ * In theory, the "ibm,associativity" property may contain multiple
+ * associativity lists because a resource may be multiply connected
+ * into the machine.  This resource then has different associativity
+ * characteristics relative to its multiple connections.  We ignore
+ * this for now.  We also assume that all cpu and memory sets have
+ * their distances represented at a common level.  This won't be
+ * true for heirarchical NUMA.
+ *
+ * In any case the ibm,associativity-reference-points should give
+ * the correct depth for a normal NUMA system.
+ *
+ * - Dave Hansen <haveblue@us.ibm.com>
+ */
+static int __init find_min_common_depth(void)
+{
+	int depth;
+	unsigned int *ref_points;
+	struct device_node *rtas_root;
+	unsigned int len;
+
+	rtas_root = of_find_node_by_path("/rtas");
+
+	if (!rtas_root)
+		return -1;
+
+	/*
+	 * this property is 2 32-bit integers, each representing a level of
+	 * depth in the associativity nodes.  The first is for an SMP
+	 * configuration (should be all 0's) and the second is for a normal
+	 * NUMA configuration.
+	 */
+	ref_points = (unsigned int *)get_property(rtas_root,
+			"ibm,associativity-reference-points", &len);
+
+	if ((len >= 1) && ref_points) {
+		depth = ref_points[1];
+	} else {
+		dbg("WARNING: could not find NUMA "
+		    "associativity reference point\n");
+		depth = -1;
+	}
+	of_node_put(rtas_root);
+
+	return depth;
+}
+
+static int __init get_mem_addr_cells(void)
+{
+	struct device_node *memory = NULL;
+	int rc;
+
+	memory = of_find_node_by_type(memory, "memory");
+	if (!memory)
+		return 0; /* it won't matter */
+
+	rc = prom_n_addr_cells(memory);
+	return rc;
+}
+
+static int __init get_mem_size_cells(void)
+{
+	struct device_node *memory = NULL;
+	int rc;
+
+	memory = of_find_node_by_type(memory, "memory");
+	if (!memory)
+		return 0; /* it won't matter */
+	rc = prom_n_size_cells(memory);
+	return rc;
+}
+
+static unsigned long read_n_cells(int n, unsigned int **buf)
+{
+	unsigned long result = 0;
+
+	while (n--) {
+		result = (result << 32) | **buf;
+		(*buf)++;
+	}
+	return result;
+}
+
+/*
+ * Figure out to which domain a cpu belongs and stick it there.
+ * Return the id of the domain used.
+ */
+static int numa_setup_cpu(unsigned long lcpu)
+{
+	int numa_domain = 0;
+	struct device_node *cpu = find_cpu_node(lcpu);
+
+	if (!cpu) {
+		WARN_ON(1);
+		goto out;
+	}
+
+	numa_domain = of_node_numa_domain(cpu);
+
+	if (numa_domain >= num_online_nodes()) {
+		/*
+		 * POWER4 LPAR uses 0xffff as invalid node,
+		 * dont warn in this case.
+		 */
+		if (numa_domain != 0xffff)
+			printk(KERN_ERR "WARNING: cpu %ld "
+			       "maps to invalid NUMA node %d\n",
+			       lcpu, numa_domain);
+		numa_domain = 0;
+	}
+out:
+	node_set_online(numa_domain);
+
+	map_cpu_to_node(lcpu, numa_domain);
+
+	of_node_put(cpu);
+
+	return numa_domain;
+}
+
+static int cpu_numa_callback(struct notifier_block *nfb,
+			     unsigned long action,
+			     void *hcpu)
+{
+	unsigned long lcpu = (unsigned long)hcpu;
+	int ret = NOTIFY_DONE;
+
+	switch (action) {
+	case CPU_UP_PREPARE:
+		if (min_common_depth == -1 || !numa_enabled)
+			map_cpu_to_node(lcpu, 0);
+		else
+			numa_setup_cpu(lcpu);
+		ret = NOTIFY_OK;
+		break;
+#ifdef CONFIG_HOTPLUG_CPU
+	case CPU_DEAD:
+	case CPU_UP_CANCELED:
+		unmap_cpu_from_node(lcpu);
+		break;
+		ret = NOTIFY_OK;
+#endif
+	}
+	return ret;
+}
+
+/*
+ * Check and possibly modify a memory region to enforce the memory limit.
+ *
+ * Returns the size the region should have to enforce the memory limit.
+ * This will either be the original value of size, a truncated value,
+ * or zero. If the returned value of size is 0 the region should be
+ * discarded as it lies wholy above the memory limit.
+ */
+static unsigned long __init numa_enforce_memory_limit(unsigned long start, unsigned long size)
+{
+	/*
+	 * We use lmb_end_of_DRAM() in here instead of memory_limit because
+	 * we've already adjusted it for the limit and it takes care of
+	 * having memory holes below the limit.
+	 */
+	extern unsigned long memory_limit;
+
+	if (! memory_limit)
+		return size;
+
+	if (start + size <= lmb_end_of_DRAM())
+		return size;
+
+	if (start >= lmb_end_of_DRAM())
+		return 0;
+
+	return lmb_end_of_DRAM() - start;
+}
+
+static int __init parse_numa_properties(void)
+{
+	struct device_node *cpu = NULL;
+	struct device_node *memory = NULL;
+	int addr_cells, size_cells;
+	int max_domain = 0;
+	long entries = lmb_end_of_DRAM() >> MEMORY_INCREMENT_SHIFT;
+	unsigned long i;
+
+	if (numa_enabled == 0) {
+		printk(KERN_WARNING "NUMA disabled by user\n");
+		return -1;
+	}
+
+	numa_memory_lookup_table =
+		(char *)abs_to_virt(lmb_alloc(entries * sizeof(char), 1));
+	memset(numa_memory_lookup_table, 0, entries * sizeof(char));
+
+	for (i = 0; i < entries ; i++)
+		numa_memory_lookup_table[i] = ARRAY_INITIALISER;
+
+	min_common_depth = find_min_common_depth();
+
+	dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth);
+	if (min_common_depth < 0)
+		return min_common_depth;
+
+	max_domain = numa_setup_cpu(boot_cpuid);
+
+	/*
+	 * Even though we connect cpus to numa domains later in SMP init,
+	 * we need to know the maximum node id now. This is because each
+	 * node id must have NODE_DATA etc backing it.
+	 * As a result of hotplug we could still have cpus appear later on
+	 * with larger node ids. In that case we force the cpu into node 0.
+	 */
+	for_each_cpu(i) {
+		int numa_domain;
+
+		cpu = find_cpu_node(i);
+
+		if (cpu) {
+			numa_domain = of_node_numa_domain(cpu);
+			of_node_put(cpu);
+
+			if (numa_domain < MAX_NUMNODES &&
+			    max_domain < numa_domain)
+				max_domain = numa_domain;
+		}
+	}
+
+	addr_cells = get_mem_addr_cells();
+	size_cells = get_mem_size_cells();
+	memory = NULL;
+	while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
+		unsigned long start;
+		unsigned long size;
+		int numa_domain;
+		int ranges;
+		unsigned int *memcell_buf;
+		unsigned int len;
+
+		memcell_buf = (unsigned int *)get_property(memory, "reg", &len);
+		if (!memcell_buf || len <= 0)
+			continue;
+
+		ranges = memory->n_addrs;
+new_range:
+		/* these are order-sensitive, and modify the buffer pointer */
+		start = read_n_cells(addr_cells, &memcell_buf);
+		size = read_n_cells(size_cells, &memcell_buf);
+
+		start = _ALIGN_DOWN(start, MEMORY_INCREMENT);
+		size = _ALIGN_UP(size, MEMORY_INCREMENT);
+
+		numa_domain = of_node_numa_domain(memory);
+
+		if (numa_domain >= MAX_NUMNODES) {
+			if (numa_domain != 0xffff)
+				printk(KERN_ERR "WARNING: memory at %lx maps "
+				       "to invalid NUMA node %d\n", start,
+				       numa_domain);
+			numa_domain = 0;
+		}
+
+		if (max_domain < numa_domain)
+			max_domain = numa_domain;
+
+		if (! (size = numa_enforce_memory_limit(start, size))) {
+			if (--ranges)
+				goto new_range;
+			else
+				continue;
+		}
+
+		/*
+		 * Initialize new node struct, or add to an existing one.
+		 */
+		if (init_node_data[numa_domain].node_end_pfn) {
+			if ((start / PAGE_SIZE) <
+			    init_node_data[numa_domain].node_start_pfn)
+				init_node_data[numa_domain].node_start_pfn =
+					start / PAGE_SIZE;
+			if (((start / PAGE_SIZE) + (size / PAGE_SIZE)) >
+			    init_node_data[numa_domain].node_end_pfn)
+				init_node_data[numa_domain].node_end_pfn =
+					(start / PAGE_SIZE) +
+					(size / PAGE_SIZE);
+
+			init_node_data[numa_domain].node_present_pages +=
+				size / PAGE_SIZE;
+		} else {
+			node_set_online(numa_domain);
+
+			init_node_data[numa_domain].node_start_pfn =
+				start / PAGE_SIZE;
+			init_node_data[numa_domain].node_end_pfn =
+				init_node_data[numa_domain].node_start_pfn +
+				size / PAGE_SIZE;
+			init_node_data[numa_domain].node_present_pages =
+				size / PAGE_SIZE;
+		}
+
+		for (i = start ; i < (start+size); i += MEMORY_INCREMENT)
+			numa_memory_lookup_table[i >> MEMORY_INCREMENT_SHIFT] =
+				numa_domain;
+
+		if (--ranges)
+			goto new_range;
+	}
+
+	for (i = 0; i <= max_domain; i++)
+		node_set_online(i);
+
+	return 0;
+}
+
+static void __init setup_nonnuma(void)
+{
+	unsigned long top_of_ram = lmb_end_of_DRAM();
+	unsigned long total_ram = lmb_phys_mem_size();
+	unsigned long i;
+
+	printk(KERN_INFO "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
+	       top_of_ram, total_ram);
+	printk(KERN_INFO "Memory hole size: %ldMB\n",
+	       (top_of_ram - total_ram) >> 20);
+
+	if (!numa_memory_lookup_table) {
+		long entries = top_of_ram >> MEMORY_INCREMENT_SHIFT;
+		numa_memory_lookup_table =
+			(char *)abs_to_virt(lmb_alloc(entries * sizeof(char), 1));
+		memset(numa_memory_lookup_table, 0, entries * sizeof(char));
+		for (i = 0; i < entries ; i++)
+			numa_memory_lookup_table[i] = ARRAY_INITIALISER;
+	}
+
+	map_cpu_to_node(boot_cpuid, 0);
+
+	node_set_online(0);
+
+	init_node_data[0].node_start_pfn = 0;
+	init_node_data[0].node_end_pfn = lmb_end_of_DRAM() / PAGE_SIZE;
+	init_node_data[0].node_present_pages = total_ram / PAGE_SIZE;
+
+	for (i = 0 ; i < top_of_ram; i += MEMORY_INCREMENT)
+		numa_memory_lookup_table[i >> MEMORY_INCREMENT_SHIFT] = 0;
+}
+
+static void __init dump_numa_topology(void)
+{
+	unsigned int node;
+	unsigned int count;
+
+	if (min_common_depth == -1 || !numa_enabled)
+		return;
+
+	for_each_online_node(node) {
+		unsigned long i;
+
+		printk(KERN_INFO "Node %d Memory:", node);
+
+		count = 0;
+
+		for (i = 0; i < lmb_end_of_DRAM(); i += MEMORY_INCREMENT) {
+			if (numa_memory_lookup_table[i >> MEMORY_INCREMENT_SHIFT] == node) {
+				if (count == 0)
+					printk(" 0x%lx", i);
+				++count;
+			} else {
+				if (count > 0)
+					printk("-0x%lx", i);
+				count = 0;
+			}
+		}
+
+		if (count > 0)
+			printk("-0x%lx", i);
+		printk("\n");
+	}
+	return;
+}
+
+/*
+ * Allocate some memory, satisfying the lmb or bootmem allocator where
+ * required. nid is the preferred node and end is the physical address of
+ * the highest address in the node.
+ *
+ * Returns the physical address of the memory.
+ */
+static unsigned long careful_allocation(int nid, unsigned long size,
+					unsigned long align, unsigned long end)
+{
+	unsigned long ret = lmb_alloc_base(size, align, end);
+
+	/* retry over all memory */
+	if (!ret)
+		ret = lmb_alloc_base(size, align, lmb_end_of_DRAM());
+
+	if (!ret)
+		panic("numa.c: cannot allocate %lu bytes on node %d",
+		      size, nid);
+
+	/*
+	 * If the memory came from a previously allocated node, we must
+	 * retry with the bootmem allocator.
+	 */
+	if (pa_to_nid(ret) < nid) {
+		nid = pa_to_nid(ret);
+		ret = (unsigned long)__alloc_bootmem_node(NODE_DATA(nid),
+				size, align, 0);
+
+		if (!ret)
+			panic("numa.c: cannot allocate %lu bytes on node %d",
+			      size, nid);
+
+		ret = virt_to_abs(ret);
+
+		dbg("alloc_bootmem %lx %lx\n", ret, size);
+	}
+
+	return ret;
+}
+
+void __init do_init_bootmem(void)
+{
+	int nid;
+	int addr_cells, size_cells;
+	struct device_node *memory = NULL;
+	static struct notifier_block ppc64_numa_nb = {
+		.notifier_call = cpu_numa_callback,
+		.priority = 1 /* Must run before sched domains notifier. */
+	};
+
+	min_low_pfn = 0;
+	max_low_pfn = lmb_end_of_DRAM() >> PAGE_SHIFT;
+	max_pfn = max_low_pfn;
+
+	if (parse_numa_properties())
+		setup_nonnuma();
+	else
+		dump_numa_topology();
+
+	register_cpu_notifier(&ppc64_numa_nb);
+
+	for_each_online_node(nid) {
+		unsigned long start_paddr, end_paddr;
+		int i;
+		unsigned long bootmem_paddr;
+		unsigned long bootmap_pages;
+
+		start_paddr = init_node_data[nid].node_start_pfn * PAGE_SIZE;
+		end_paddr = init_node_data[nid].node_end_pfn * PAGE_SIZE;
+
+		/* Allocate the node structure node local if possible */
+		NODE_DATA(nid) = (struct pglist_data *)careful_allocation(nid,
+					sizeof(struct pglist_data),
+					SMP_CACHE_BYTES, end_paddr);
+		NODE_DATA(nid) = abs_to_virt(NODE_DATA(nid));
+		memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
+
+  		dbg("node %d\n", nid);
+		dbg("NODE_DATA() = %p\n", NODE_DATA(nid));
+
+		NODE_DATA(nid)->bdata = &plat_node_bdata[nid];
+		NODE_DATA(nid)->node_start_pfn =
+			init_node_data[nid].node_start_pfn;
+		NODE_DATA(nid)->node_spanned_pages =
+			end_paddr - start_paddr;
+
+		if (NODE_DATA(nid)->node_spanned_pages == 0)
+  			continue;
+
+  		dbg("start_paddr = %lx\n", start_paddr);
+  		dbg("end_paddr = %lx\n", end_paddr);
+
+		bootmap_pages = bootmem_bootmap_pages((end_paddr - start_paddr) >> PAGE_SHIFT);
+
+		bootmem_paddr = careful_allocation(nid,
+				bootmap_pages << PAGE_SHIFT,
+				PAGE_SIZE, end_paddr);
+		memset(abs_to_virt(bootmem_paddr), 0,
+		       bootmap_pages << PAGE_SHIFT);
+		dbg("bootmap_paddr = %lx\n", bootmem_paddr);
+
+		init_bootmem_node(NODE_DATA(nid), bootmem_paddr >> PAGE_SHIFT,
+				  start_paddr >> PAGE_SHIFT,
+				  end_paddr >> PAGE_SHIFT);
+
+		/*
+		 * We need to do another scan of all memory sections to
+		 * associate memory with the correct node.
+		 */
+		addr_cells = get_mem_addr_cells();
+		size_cells = get_mem_size_cells();
+		memory = NULL;
+		while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
+			unsigned long mem_start, mem_size;
+			int numa_domain, ranges;
+			unsigned int *memcell_buf;
+			unsigned int len;
+
+			memcell_buf = (unsigned int *)get_property(memory, "reg", &len);
+			if (!memcell_buf || len <= 0)
+				continue;
+
+			ranges = memory->n_addrs;	/* ranges in cell */
+new_range:
+			mem_start = read_n_cells(addr_cells, &memcell_buf);
+			mem_size = read_n_cells(size_cells, &memcell_buf);
+			if (numa_enabled) {
+				numa_domain = of_node_numa_domain(memory);
+				if (numa_domain  >= MAX_NUMNODES)
+					numa_domain = 0;
+			} else
+				numa_domain =  0;
+
+			if (numa_domain != nid)
+				continue;
+
+			mem_size = numa_enforce_memory_limit(mem_start, mem_size);
+  			if (mem_size) {
+  				dbg("free_bootmem %lx %lx\n", mem_start, mem_size);
+  				free_bootmem_node(NODE_DATA(nid), mem_start, mem_size);
+			}
+
+			if (--ranges)		/* process all ranges in cell */
+				goto new_range;
+		}
+
+		/*
+		 * Mark reserved regions on this node
+		 */
+		for (i = 0; i < lmb.reserved.cnt; i++) {
+			unsigned long physbase = lmb.reserved.region[i].base;
+			unsigned long size = lmb.reserved.region[i].size;
+
+			if (pa_to_nid(physbase) != nid &&
+			    pa_to_nid(physbase+size-1) != nid)
+				continue;
+
+			if (physbase < end_paddr &&
+			    (physbase+size) > start_paddr) {
+				/* overlaps */
+				if (physbase < start_paddr) {
+					size -= start_paddr - physbase;
+					physbase = start_paddr;
+				}
+
+				if (size > end_paddr - physbase)
+					size = end_paddr - physbase;
+
+				dbg("reserve_bootmem %lx %lx\n", physbase,
+				    size);
+				reserve_bootmem_node(NODE_DATA(nid), physbase,
+						     size);
+			}
+		}
+		/*
+		 * This loop may look famaliar, but we have to do it again
+		 * after marking our reserved memory to mark memory present
+		 * for sparsemem.
+		 */
+		addr_cells = get_mem_addr_cells();
+		size_cells = get_mem_size_cells();
+		memory = NULL;
+		while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
+			unsigned long mem_start, mem_size;
+			int numa_domain, ranges;
+			unsigned int *memcell_buf;
+			unsigned int len;
+
+			memcell_buf = (unsigned int *)get_property(memory, "reg", &len);
+			if (!memcell_buf || len <= 0)
+				continue;
+
+			ranges = memory->n_addrs;	/* ranges in cell */
+new_range2:
+			mem_start = read_n_cells(addr_cells, &memcell_buf);
+			mem_size = read_n_cells(size_cells, &memcell_buf);
+			if (numa_enabled) {
+				numa_domain = of_node_numa_domain(memory);
+				if (numa_domain  >= MAX_NUMNODES)
+					numa_domain = 0;
+			} else
+				numa_domain =  0;
+
+			if (numa_domain != nid)
+				continue;
+
+			mem_size = numa_enforce_memory_limit(mem_start, mem_size);
+			memory_present(numa_domain, mem_start >> PAGE_SHIFT,
+				       (mem_start + mem_size) >> PAGE_SHIFT);
+
+			if (--ranges)		/* process all ranges in cell */
+				goto new_range2;
+		}
+
+	}
+}
+
+void __init paging_init(void)
+{
+	unsigned long zones_size[MAX_NR_ZONES];
+	unsigned long zholes_size[MAX_NR_ZONES];
+	int nid;
+
+	memset(zones_size, 0, sizeof(zones_size));
+	memset(zholes_size, 0, sizeof(zholes_size));
+
+	for_each_online_node(nid) {
+		unsigned long start_pfn;
+		unsigned long end_pfn;
+
+		start_pfn = init_node_data[nid].node_start_pfn;
+		end_pfn = init_node_data[nid].node_end_pfn;
+
+		zones_size[ZONE_DMA] = end_pfn - start_pfn;
+		zholes_size[ZONE_DMA] = zones_size[ZONE_DMA] -
+			init_node_data[nid].node_present_pages;
+
+		dbg("free_area_init node %d %lx %lx (hole: %lx)\n", nid,
+		    zones_size[ZONE_DMA], start_pfn, zholes_size[ZONE_DMA]);
+
+		free_area_init_node(nid, NODE_DATA(nid), zones_size,
+							start_pfn, zholes_size);
+	}
+}
+
+static int __init early_numa(char *p)
+{
+	if (!p)
+		return 0;
+
+	if (strstr(p, "off"))
+		numa_enabled = 0;
+
+	if (strstr(p, "debug"))
+		numa_debug = 1;
+
+	return 0;
+}
+early_param("numa", early_numa);