arch/ppc64/mm/numa.c - kernel/msm-4.9 - Gitiles

 /*
  * 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);
	/*
	* 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);