/*
   * Procedures for maintaining information about logical memory blocks.
   *
   * Peter Bergner, IBM Corp.	June 2001.
   * Copyright (C) 2001 Peter Bergner.
   *
   *      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/kernel.h>

  #include <linux/slab.h>

  #include <linux/init.h>
  #include <linux/bitops.h>

  #include <linux/poison.h>

  #include <linux/pfn.h>

  #include <linux/debugfs.h>
  #include <linux/seq_file.h>

  #include <linux/memblock.h>

  static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
  static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS] __initdata_memblock;
  
  struct memblock memblock __initdata_memblock = {
  	.memory.regions		= memblock_memory_init_regions,
  	.memory.cnt		= 1,	/* empty dummy entry */
  	.memory.max		= INIT_MEMBLOCK_REGIONS,
  
  	.reserved.regions	= memblock_reserved_init_regions,
  	.reserved.cnt		= 1,	/* empty dummy entry */
  	.reserved.max		= INIT_MEMBLOCK_REGIONS,
  
  	.current_limit		= MEMBLOCK_ALLOC_ANYWHERE,
  };

  int memblock_debug __initdata_memblock;

  static int memblock_can_resize __initdata_memblock;

  static int memblock_memory_in_slab __initdata_memblock = 0;
  static int memblock_reserved_in_slab __initdata_memblock = 0;

  /* inline so we don't get a warning when pr_debug is compiled out */

  static __init_memblock const char *
  memblock_type_name(struct memblock_type *type)

  {
  	if (type == &memblock.memory)
  		return "memory";
  	else if (type == &memblock.reserved)
  		return "reserved";
  	else
  		return "unknown";
  }

  /* adjust *@size so that (@base + *@size) doesn't overflow, return new size */
  static inline phys_addr_t memblock_cap_size(phys_addr_t base, phys_addr_t *size)
  {
  	return *size = min(*size, (phys_addr_t)ULLONG_MAX - base);
  }

  /*
   * Address comparison utilities
   */

  static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, phys_addr_t size1,

  				       phys_addr_t base2, phys_addr_t size2)

  {
  	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
  }

  static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
  					phys_addr_t base, phys_addr_t size)

  {
  	unsigned long i;
  
  	for (i = 0; i < type->cnt; i++) {
  		phys_addr_t rgnbase = type->regions[i].base;
  		phys_addr_t rgnsize = type->regions[i].size;
  		if (memblock_addrs_overlap(base, size, rgnbase, rgnsize))
  			break;
  	}
  
  	return (i < type->cnt) ? i : -1;
  }

  /**
   * memblock_find_in_range_node - find free area in given range and node
   * @start: start of candidate range
   * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
   * @size: size of free area to find
   * @align: alignment of free area to find
   * @nid: nid of the free area to find, %MAX_NUMNODES for any node
   *
   * Find @size free area aligned to @align in the specified range and node.
   *
   * RETURNS:
   * Found address on success, %0 on failure.

   */

  phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t start,
  					phys_addr_t end, phys_addr_t size,
  					phys_addr_t align, int nid)
  {
  	phys_addr_t this_start, this_end, cand;
  	u64 i;
  
  	/* pump up @end */
  	if (end == MEMBLOCK_ALLOC_ACCESSIBLE)
  		end = memblock.current_limit;
  
  	/* avoid allocating the first page */
  	start = max_t(phys_addr_t, start, PAGE_SIZE);
  	end = max(start, end);
  
  	for_each_free_mem_range_reverse(i, nid, &this_start, &this_end, NULL) {
  		this_start = clamp(this_start, start, end);
  		this_end = clamp(this_end, start, end);
  
  		if (this_end < size)
  			continue;
  
  		cand = round_down(this_end - size, align);
  		if (cand >= this_start)
  			return cand;
  	}
  	return 0;
  }

  /**
   * memblock_find_in_range - find free area in given range
   * @start: start of candidate range
   * @end: end of candidate range, can be %MEMBLOCK_ALLOC_{ANYWHERE|ACCESSIBLE}
   * @size: size of free area to find
   * @align: alignment of free area to find
   *
   * Find @size free area aligned to @align in the specified range.
   *
   * RETURNS:
   * Found address on success, %0 on failure.

   */

  phys_addr_t __init_memblock memblock_find_in_range(phys_addr_t start,
  					phys_addr_t end, phys_addr_t size,
  					phys_addr_t align)

  {

  	return memblock_find_in_range_node(start, end, size, align,
  					   MAX_NUMNODES);

  }

  static void __init_memblock memblock_remove_region(struct memblock_type *type, unsigned long r)

  {

  	type->total_size -= type->regions[r].size;

  	memmove(&type->regions[r], &type->regions[r + 1],
  		(type->cnt - (r + 1)) * sizeof(type->regions[r]));

  	type->cnt--;

  	/* Special case for empty arrays */
  	if (type->cnt == 0) {

  		WARN_ON(type->total_size != 0);

  		type->cnt = 1;
  		type->regions[0].base = 0;
  		type->regions[0].size = 0;

  		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);

  	}

  }

  phys_addr_t __init_memblock get_allocated_memblock_reserved_regions_info(
  					phys_addr_t *addr)
  {
  	if (memblock.reserved.regions == memblock_reserved_init_regions)
  		return 0;
  
  	*addr = __pa(memblock.reserved.regions);
  
  	return PAGE_ALIGN(sizeof(struct memblock_region) *
  			  memblock.reserved.max);
  }

  /**
   * memblock_double_array - double the size of the memblock regions array
   * @type: memblock type of the regions array being doubled
   * @new_area_start: starting address of memory range to avoid overlap with
   * @new_area_size: size of memory range to avoid overlap with
   *
   * Double the size of the @type regions array. If memblock is being used to
   * allocate memory for a new reserved regions array and there is a previously
   * allocated memory range [@new_area_start,@new_area_start+@new_area_size]
   * waiting to be reserved, ensure the memory used by the new array does
   * not overlap.
   *
   * RETURNS:
   * 0 on success, -1 on failure.
   */
  static int __init_memblock memblock_double_array(struct memblock_type *type,
  						phys_addr_t new_area_start,
  						phys_addr_t new_area_size)

  {
  	struct memblock_region *new_array, *old_array;

  	phys_addr_t old_alloc_size, new_alloc_size;

  	phys_addr_t old_size, new_size, addr;
  	int use_slab = slab_is_available();

  	int *in_slab;

  
  	/* We don't allow resizing until we know about the reserved regions
  	 * of memory that aren't suitable for allocation
  	 */
  	if (!memblock_can_resize)
  		return -1;

  	/* Calculate new doubled size */
  	old_size = type->max * sizeof(struct memblock_region);
  	new_size = old_size << 1;

  	/*
  	 * We need to allocated new one align to PAGE_SIZE,
  	 *   so we can free them completely later.
  	 */
  	old_alloc_size = PAGE_ALIGN(old_size);
  	new_alloc_size = PAGE_ALIGN(new_size);

  	/* Retrieve the slab flag */
  	if (type == &memblock.memory)
  		in_slab = &memblock_memory_in_slab;
  	else
  		in_slab = &memblock_reserved_in_slab;

  	/* Try to find some space for it.
  	 *
  	 * WARNING: We assume that either slab_is_available() and we use it or

  	 * we use MEMBLOCK for allocations. That means that this is unsafe to
  	 * use when bootmem is currently active (unless bootmem itself is
  	 * implemented on top of MEMBLOCK which isn't the case yet)

  	 *
  	 * This should however not be an issue for now, as we currently only

  	 * call into MEMBLOCK while it's still active, or much later when slab
  	 * is active for memory hotplug operations

  	 */
  	if (use_slab) {
  		new_array = kmalloc(new_size, GFP_KERNEL);

  		addr = new_array ? __pa(new_array) : 0;

  	} else {

  		/* only exclude range when trying to double reserved.regions */
  		if (type != &memblock.reserved)
  			new_area_start = new_area_size = 0;
  
  		addr = memblock_find_in_range(new_area_start + new_area_size,
  						memblock.current_limit,

  						new_alloc_size, PAGE_SIZE);

  		if (!addr && new_area_size)
  			addr = memblock_find_in_range(0,

  				min(new_area_start, memblock.current_limit),
  				new_alloc_size, PAGE_SIZE);

  		new_array = addr ? __va(addr) : NULL;

  	}

  	if (!addr) {

  		pr_err("memblock: Failed to double %s array from %ld to %ld entries !
  ",
  		       memblock_type_name(type), type->max, type->max * 2);
  		return -1;
  	}

  	memblock_dbg("memblock: %s is doubled to %ld at [%#010llx-%#010llx]",
  			memblock_type_name(type), type->max * 2, (u64)addr,
  			(u64)addr + new_size - 1);

  	/*
  	 * Found space, we now need to move the array over before we add the
  	 * reserved region since it may be our reserved array itself that is
  	 * full.

  	 */
  	memcpy(new_array, type->regions, old_size);
  	memset(new_array + type->max, 0, old_size);
  	old_array = type->regions;
  	type->regions = new_array;
  	type->max <<= 1;

  	/* Free old array. We needn't free it if the array is the static one */

  	if (*in_slab)
  		kfree(old_array);
  	else if (old_array != memblock_memory_init_regions &&
  		 old_array != memblock_reserved_init_regions)

  		memblock_free(__pa(old_array), old_alloc_size);

  	/*
  	 * Reserve the new array if that comes from the memblock.  Otherwise, we
  	 * needn't do it

  	 */
  	if (!use_slab)

  		BUG_ON(memblock_reserve(addr, new_alloc_size));

  
  	/* Update slab flag */
  	*in_slab = use_slab;

  	return 0;
  }

  /**
   * memblock_merge_regions - merge neighboring compatible regions
   * @type: memblock type to scan
   *
   * Scan @type and merge neighboring compatible regions.
   */
  static void __init_memblock memblock_merge_regions(struct memblock_type *type)

  {

  	int i = 0;

  	/* cnt never goes below 1 */
  	while (i < type->cnt - 1) {
  		struct memblock_region *this = &type->regions[i];
  		struct memblock_region *next = &type->regions[i + 1];

  		if (this->base + this->size != next->base ||
  		    memblock_get_region_node(this) !=
  		    memblock_get_region_node(next)) {

  			BUG_ON(this->base + this->size > next->base);
  			i++;
  			continue;

  		}

  		this->size += next->size;

  		/* move forward from next + 1, index of which is i + 2 */
  		memmove(next, next + 1, (type->cnt - (i + 2)) * sizeof(*next));

  		type->cnt--;

  	}

  }

  /**
   * memblock_insert_region - insert new memblock region

   * @type:	memblock type to insert into
   * @idx:	index for the insertion point
   * @base:	base address of the new region
   * @size:	size of the new region
   * @nid:	node id of the new region

   *
   * Insert new memblock region [@base,@base+@size) into @type at @idx.
   * @type must already have extra room to accomodate the new region.
   */
  static void __init_memblock memblock_insert_region(struct memblock_type *type,
  						   int idx, phys_addr_t base,

  						   phys_addr_t size, int nid)

  {
  	struct memblock_region *rgn = &type->regions[idx];
  
  	BUG_ON(type->cnt >= type->max);
  	memmove(rgn + 1, rgn, (type->cnt - idx) * sizeof(*rgn));
  	rgn->base = base;
  	rgn->size = size;

  	memblock_set_region_node(rgn, nid);

  	type->cnt++;

  	type->total_size += size;

  }
  
  /**
   * memblock_add_region - add new memblock region
   * @type: memblock type to add new region into
   * @base: base address of the new region
   * @size: size of the new region

   * @nid: nid of the new region

   *
   * Add new memblock region [@base,@base+@size) into @type.  The new region
   * is allowed to overlap with existing ones - overlaps don't affect already
   * existing regions.  @type is guaranteed to be minimal (all neighbouring
   * compatible regions are merged) after the addition.
   *
   * RETURNS:
   * 0 on success, -errno on failure.
   */

  static int __init_memblock memblock_add_region(struct memblock_type *type,

  				phys_addr_t base, phys_addr_t size, int nid)

  {
  	bool insert = false;

  	phys_addr_t obase = base;
  	phys_addr_t end = base + memblock_cap_size(base, &size);

  	int i, nr_new;

  	if (!size)
  		return 0;

  	/* special case for empty array */
  	if (type->regions[0].size == 0) {

  		WARN_ON(type->cnt != 1 || type->total_size);

  		type->regions[0].base = base;
  		type->regions[0].size = size;

  		memblock_set_region_node(&type->regions[0], nid);

  		type->total_size = size;

  		return 0;

  	}

  repeat:
  	/*
  	 * The following is executed twice.  Once with %false @insert and
  	 * then with %true.  The first counts the number of regions needed
  	 * to accomodate the new area.  The second actually inserts them.

  	 */

  	base = obase;
  	nr_new = 0;

  	for (i = 0; i < type->cnt; i++) {
  		struct memblock_region *rgn = &type->regions[i];
  		phys_addr_t rbase = rgn->base;
  		phys_addr_t rend = rbase + rgn->size;
  
  		if (rbase >= end)

  			break;

  		if (rend <= base)
  			continue;
  		/*
  		 * @rgn overlaps.  If it separates the lower part of new
  		 * area, insert that portion.
  		 */
  		if (rbase > base) {
  			nr_new++;
  			if (insert)
  				memblock_insert_region(type, i++, base,

  						       rbase - base, nid);

  		}

  		/* area below @rend is dealt with, forget about it */
  		base = min(rend, end);

  	}

  
  	/* insert the remaining portion */
  	if (base < end) {
  		nr_new++;
  		if (insert)

  			memblock_insert_region(type, i, base, end - base, nid);

  	}

  	/*
  	 * If this was the first round, resize array and repeat for actual
  	 * insertions; otherwise, merge and return.

  	 */

  	if (!insert) {
  		while (type->cnt + nr_new > type->max)

  			if (memblock_double_array(type, obase, size) < 0)

  				return -ENOMEM;
  		insert = true;
  		goto repeat;
  	} else {
  		memblock_merge_regions(type);
  		return 0;

  	}

  }

  int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
  				       int nid)
  {
  	return memblock_add_region(&memblock.memory, base, size, nid);
  }

  int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)

  {

  	return memblock_add_region(&memblock.memory, base, size, MAX_NUMNODES);

  }

  /**
   * memblock_isolate_range - isolate given range into disjoint memblocks
   * @type: memblock type to isolate range for
   * @base: base of range to isolate
   * @size: size of range to isolate
   * @start_rgn: out parameter for the start of isolated region
   * @end_rgn: out parameter for the end of isolated region
   *
   * Walk @type and ensure that regions don't cross the boundaries defined by
   * [@base,@base+@size).  Crossing regions are split at the boundaries,
   * which may create at most two more regions.  The index of the first
   * region inside the range is returned in *@start_rgn and end in *@end_rgn.
   *
   * RETURNS:
   * 0 on success, -errno on failure.
   */
  static int __init_memblock memblock_isolate_range(struct memblock_type *type,
  					phys_addr_t base, phys_addr_t size,
  					int *start_rgn, int *end_rgn)
  {

  	phys_addr_t end = base + memblock_cap_size(base, &size);

  	int i;
  
  	*start_rgn = *end_rgn = 0;

  	if (!size)
  		return 0;

  	/* we'll create at most two more regions */
  	while (type->cnt + 2 > type->max)

  		if (memblock_double_array(type, base, size) < 0)

  			return -ENOMEM;
  
  	for (i = 0; i < type->cnt; i++) {
  		struct memblock_region *rgn = &type->regions[i];
  		phys_addr_t rbase = rgn->base;
  		phys_addr_t rend = rbase + rgn->size;
  
  		if (rbase >= end)
  			break;
  		if (rend <= base)
  			continue;
  
  		if (rbase < base) {
  			/*
  			 * @rgn intersects from below.  Split and continue
  			 * to process the next region - the new top half.
  			 */
  			rgn->base = base;

  			rgn->size -= base - rbase;
  			type->total_size -= base - rbase;

  			memblock_insert_region(type, i, rbase, base - rbase,

  					       memblock_get_region_node(rgn));

  		} else if (rend > end) {
  			/*
  			 * @rgn intersects from above.  Split and redo the
  			 * current region - the new bottom half.
  			 */
  			rgn->base = end;

  			rgn->size -= end - rbase;
  			type->total_size -= end - rbase;

  			memblock_insert_region(type, i--, rbase, end - rbase,

  					       memblock_get_region_node(rgn));

  		} else {
  			/* @rgn is fully contained, record it */
  			if (!*end_rgn)
  				*start_rgn = i;
  			*end_rgn = i + 1;
  		}
  	}
  
  	return 0;
  }

  static int __init_memblock __memblock_remove(struct memblock_type *type,
  					     phys_addr_t base, phys_addr_t size)

  {

  	int start_rgn, end_rgn;
  	int i, ret;

  	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
  	if (ret)
  		return ret;

  	for (i = end_rgn - 1; i >= start_rgn; i--)
  		memblock_remove_region(type, i);

  	return 0;

  }

  int __init_memblock memblock_remove(phys_addr_t base, phys_addr_t size)

  {
  	return __memblock_remove(&memblock.memory, base, size);
  }

  int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)

  {

  	memblock_dbg("   memblock_free: [%#016llx-%#016llx] %pF
  ",

  		     (unsigned long long)base,
  		     (unsigned long long)base + size,
  		     (void *)_RET_IP_);

  	return __memblock_remove(&memblock.reserved, base, size);
  }

  int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)

  {

  	struct memblock_type *_rgn = &memblock.reserved;

  	memblock_dbg("memblock_reserve: [%#016llx-%#016llx] %pF
  ",

  		     (unsigned long long)base,
  		     (unsigned long long)base + size,
  		     (void *)_RET_IP_);

  	return memblock_add_region(_rgn, base, size, MAX_NUMNODES);

  }

  /**
   * __next_free_mem_range - next function for for_each_free_mem_range()
   * @idx: pointer to u64 loop variable
   * @nid: nid: node selector, %MAX_NUMNODES for all nodes

   * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
   * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
   * @out_nid: ptr to int for nid of the range, can be %NULL

   *
   * Find the first free area from *@idx which matches @nid, fill the out
   * parameters, and update *@idx for the next iteration.  The lower 32bit of
   * *@idx contains index into memory region and the upper 32bit indexes the
   * areas before each reserved region.  For example, if reserved regions
   * look like the following,
   *
   *	0:[0-16), 1:[32-48), 2:[128-130)
   *
   * The upper 32bit indexes the following regions.
   *
   *	0:[0-0), 1:[16-32), 2:[48-128), 3:[130-MAX)
   *
   * As both region arrays are sorted, the function advances the two indices
   * in lockstep and returns each intersection.
   */
  void __init_memblock __next_free_mem_range(u64 *idx, int nid,
  					   phys_addr_t *out_start,
  					   phys_addr_t *out_end, int *out_nid)
  {
  	struct memblock_type *mem = &memblock.memory;
  	struct memblock_type *rsv = &memblock.reserved;
  	int mi = *idx & 0xffffffff;
  	int ri = *idx >> 32;
  
  	for ( ; mi < mem->cnt; mi++) {
  		struct memblock_region *m = &mem->regions[mi];
  		phys_addr_t m_start = m->base;
  		phys_addr_t m_end = m->base + m->size;
  
  		/* only memory regions are associated with nodes, check it */
  		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
  			continue;
  
  		/* scan areas before each reservation for intersection */
  		for ( ; ri < rsv->cnt + 1; ri++) {
  			struct memblock_region *r = &rsv->regions[ri];
  			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
  			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
  
  			/* if ri advanced past mi, break out to advance mi */
  			if (r_start >= m_end)
  				break;
  			/* if the two regions intersect, we're done */
  			if (m_start < r_end) {
  				if (out_start)
  					*out_start = max(m_start, r_start);
  				if (out_end)
  					*out_end = min(m_end, r_end);
  				if (out_nid)
  					*out_nid = memblock_get_region_node(m);
  				/*
  				 * The region which ends first is advanced
  				 * for the next iteration.
  				 */
  				if (m_end <= r_end)
  					mi++;
  				else
  					ri++;
  				*idx = (u32)mi | (u64)ri << 32;
  				return;
  			}
  		}
  	}
  
  	/* signal end of iteration */
  	*idx = ULLONG_MAX;
  }

  /**
   * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
   * @idx: pointer to u64 loop variable
   * @nid: nid: node selector, %MAX_NUMNODES for all nodes

   * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
   * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
   * @out_nid: ptr to int for nid of the range, can be %NULL

   *
   * Reverse of __next_free_mem_range().
   */
  void __init_memblock __next_free_mem_range_rev(u64 *idx, int nid,
  					   phys_addr_t *out_start,
  					   phys_addr_t *out_end, int *out_nid)
  {
  	struct memblock_type *mem = &memblock.memory;
  	struct memblock_type *rsv = &memblock.reserved;
  	int mi = *idx & 0xffffffff;
  	int ri = *idx >> 32;
  
  	if (*idx == (u64)ULLONG_MAX) {
  		mi = mem->cnt - 1;
  		ri = rsv->cnt;
  	}
  
  	for ( ; mi >= 0; mi--) {
  		struct memblock_region *m = &mem->regions[mi];
  		phys_addr_t m_start = m->base;
  		phys_addr_t m_end = m->base + m->size;
  
  		/* only memory regions are associated with nodes, check it */
  		if (nid != MAX_NUMNODES && nid != memblock_get_region_node(m))
  			continue;
  
  		/* scan areas before each reservation for intersection */
  		for ( ; ri >= 0; ri--) {
  			struct memblock_region *r = &rsv->regions[ri];
  			phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0;
  			phys_addr_t r_end = ri < rsv->cnt ? r->base : ULLONG_MAX;
  
  			/* if ri advanced past mi, break out to advance mi */
  			if (r_end <= m_start)
  				break;
  			/* if the two regions intersect, we're done */
  			if (m_end > r_start) {
  				if (out_start)
  					*out_start = max(m_start, r_start);
  				if (out_end)
  					*out_end = min(m_end, r_end);
  				if (out_nid)
  					*out_nid = memblock_get_region_node(m);
  
  				if (m_start >= r_start)
  					mi--;
  				else
  					ri--;
  				*idx = (u32)mi | (u64)ri << 32;
  				return;
  			}
  		}
  	}
  
  	*idx = ULLONG_MAX;
  }

  #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
  /*
   * Common iterator interface used to define for_each_mem_range().
   */
  void __init_memblock __next_mem_pfn_range(int *idx, int nid,
  				unsigned long *out_start_pfn,
  				unsigned long *out_end_pfn, int *out_nid)
  {
  	struct memblock_type *type = &memblock.memory;
  	struct memblock_region *r;
  
  	while (++*idx < type->cnt) {
  		r = &type->regions[*idx];
  
  		if (PFN_UP(r->base) >= PFN_DOWN(r->base + r->size))
  			continue;
  		if (nid == MAX_NUMNODES || nid == r->nid)
  			break;
  	}
  	if (*idx >= type->cnt) {
  		*idx = -1;
  		return;
  	}
  
  	if (out_start_pfn)
  		*out_start_pfn = PFN_UP(r->base);
  	if (out_end_pfn)
  		*out_end_pfn = PFN_DOWN(r->base + r->size);
  	if (out_nid)
  		*out_nid = r->nid;
  }
  
  /**
   * memblock_set_node - set node ID on memblock regions
   * @base: base of area to set node ID for
   * @size: size of area to set node ID for
   * @nid: node ID to set
   *
   * Set the nid of memblock memory regions in [@base,@base+@size) to @nid.
   * Regions which cross the area boundaries are split as necessary.
   *
   * RETURNS:
   * 0 on success, -errno on failure.
   */
  int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
  				      int nid)
  {
  	struct memblock_type *type = &memblock.memory;

  	int start_rgn, end_rgn;
  	int i, ret;

  	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
  	if (ret)
  		return ret;

  	for (i = start_rgn; i < end_rgn; i++)

  		memblock_set_region_node(&type->regions[i], nid);

  
  	memblock_merge_regions(type);
  	return 0;
  }
  #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */

  static phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
  					phys_addr_t align, phys_addr_t max_addr,
  					int nid)

  {

  	phys_addr_t found;

  	if (WARN_ON(!align))
  		align = __alignof__(long long);

  	/* align @size to avoid excessive fragmentation on reserved array */
  	size = round_up(size, align);

  	found = memblock_find_in_range_node(0, max_addr, size, align, nid);

  	if (found && !memblock_reserve(found, size))

  		return found;

  	return 0;

  }

  phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
  {
  	return memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE, nid);
  }
  
  phys_addr_t __init __memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)
  {
  	return memblock_alloc_base_nid(size, align, max_addr, MAX_NUMNODES);
  }

  phys_addr_t __init memblock_alloc_base(phys_addr_t size, phys_addr_t align, phys_addr_t max_addr)

  {

  	phys_addr_t alloc;
  
  	alloc = __memblock_alloc_base(size, align, max_addr);
  
  	if (alloc == 0)
  		panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.
  ",
  		      (unsigned long long) size, (unsigned long long) max_addr);
  
  	return alloc;

  }

  phys_addr_t __init memblock_alloc(phys_addr_t size, phys_addr_t align)

  {

  	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
  }

  phys_addr_t __init memblock_alloc_try_nid(phys_addr_t size, phys_addr_t align, int nid)
  {
  	phys_addr_t res = memblock_alloc_nid(size, align, nid);
  
  	if (res)
  		return res;

  	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);

  }

  
  /*
   * Remaining API functions
   */

  phys_addr_t __init memblock_phys_mem_size(void)

  {

  	return memblock.memory.total_size;

  }

  phys_addr_t __init memblock_mem_size(unsigned long limit_pfn)
  {
  	unsigned long pages = 0;
  	struct memblock_region *r;
  	unsigned long start_pfn, end_pfn;
  
  	for_each_memblock(memory, r) {
  		start_pfn = memblock_region_memory_base_pfn(r);
  		end_pfn = memblock_region_memory_end_pfn(r);
  		start_pfn = min_t(unsigned long, start_pfn, limit_pfn);
  		end_pfn = min_t(unsigned long, end_pfn, limit_pfn);
  		pages += end_pfn - start_pfn;
  	}
  
  	return (phys_addr_t)pages << PAGE_SHIFT;
  }

  /* lowest address */
  phys_addr_t __init_memblock memblock_start_of_DRAM(void)
  {
  	return memblock.memory.regions[0].base;
  }

  phys_addr_t __init_memblock memblock_end_of_DRAM(void)

  {
  	int idx = memblock.memory.cnt - 1;

  	return (memblock.memory.regions[idx].base + memblock.memory.regions[idx].size);

  }

  void __init memblock_enforce_memory_limit(phys_addr_t limit)

  {
  	unsigned long i;

  	phys_addr_t max_addr = (phys_addr_t)ULLONG_MAX;

  	if (!limit)

  		return;

  	/* find out max address */

  	for (i = 0; i < memblock.memory.cnt; i++) {

  		struct memblock_region *r = &memblock.memory.regions[i];

  		if (limit <= r->size) {
  			max_addr = r->base + limit;
  			break;

  		}

  		limit -= r->size;

  	}

  
  	/* truncate both memory and reserved regions */
  	__memblock_remove(&memblock.memory, max_addr, (phys_addr_t)ULLONG_MAX);
  	__memblock_remove(&memblock.reserved, max_addr, (phys_addr_t)ULLONG_MAX);

  }

  static int __init_memblock memblock_search(struct memblock_type *type, phys_addr_t addr)

  {
  	unsigned int left = 0, right = type->cnt;
  
  	do {
  		unsigned int mid = (right + left) / 2;
  
  		if (addr < type->regions[mid].base)
  			right = mid;
  		else if (addr >= (type->regions[mid].base +
  				  type->regions[mid].size))
  			left = mid + 1;
  		else
  			return mid;
  	} while (left < right);
  	return -1;
  }

  int __init memblock_is_reserved(phys_addr_t addr)

  {

  	return memblock_search(&memblock.reserved, addr) != -1;
  }

  int __init_memblock memblock_is_memory(phys_addr_t addr)

  {
  	return memblock_search(&memblock.memory, addr) != -1;
  }

  /**
   * memblock_is_region_memory - check if a region is a subset of memory
   * @base: base of region to check
   * @size: size of region to check
   *
   * Check if the region [@base, @base+@size) is a subset of a memory block.
   *
   * RETURNS:
   * 0 if false, non-zero if true
   */

  int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)

  {

  	int idx = memblock_search(&memblock.memory, base);

  	phys_addr_t end = base + memblock_cap_size(base, &size);

  
  	if (idx == -1)
  		return 0;

  	return memblock.memory.regions[idx].base <= base &&
  		(memblock.memory.regions[idx].base +

  		 memblock.memory.regions[idx].size) >= end;

  }

  /**
   * memblock_is_region_reserved - check if a region intersects reserved memory
   * @base: base of region to check
   * @size: size of region to check
   *
   * Check if the region [@base, @base+@size) intersects a reserved memory block.
   *
   * RETURNS:
   * 0 if false, non-zero if true
   */

  int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)

  {

  	memblock_cap_size(base, &size);

  	return memblock_overlaps_region(&memblock.reserved, base, size) >= 0;

  }

  void __init_memblock memblock_trim_memory(phys_addr_t align)
  {
  	int i;
  	phys_addr_t start, end, orig_start, orig_end;
  	struct memblock_type *mem = &memblock.memory;
  
  	for (i = 0; i < mem->cnt; i++) {
  		orig_start = mem->regions[i].base;
  		orig_end = mem->regions[i].base + mem->regions[i].size;
  		start = round_up(orig_start, align);
  		end = round_down(orig_end, align);
  
  		if (start == orig_start && end == orig_end)
  			continue;
  
  		if (start < end) {
  			mem->regions[i].base = start;
  			mem->regions[i].size = end - start;
  		} else {
  			memblock_remove_region(mem, i);
  			i--;
  		}
  	}
  }

  void __init_memblock memblock_set_current_limit(phys_addr_t limit)

  {
  	memblock.current_limit = limit;
  }

  static void __init_memblock memblock_dump(struct memblock_type *type, char *name)

  {
  	unsigned long long base, size;
  	int i;

  	pr_info(" %s.cnt  = 0x%lx
  ", name, type->cnt);

  	for (i = 0; i < type->cnt; i++) {
  		struct memblock_region *rgn = &type->regions[i];
  		char nid_buf[32] = "";
  
  		base = rgn->base;
  		size = rgn->size;
  #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
  		if (memblock_get_region_node(rgn) != MAX_NUMNODES)
  			snprintf(nid_buf, sizeof(nid_buf), " on node %d",
  				 memblock_get_region_node(rgn));
  #endif
  		pr_info(" %s[%#x]\t[%#016llx-%#016llx], %#llx bytes%s
  ",
  			name, i, base, base + size - 1, size, nid_buf);

  	}
  }

  void __init_memblock __memblock_dump_all(void)

  {

  	pr_info("MEMBLOCK configuration:
  ");

  	pr_info(" memory size = %#llx reserved size = %#llx
  ",
  		(unsigned long long)memblock.memory.total_size,
  		(unsigned long long)memblock.reserved.total_size);

  
  	memblock_dump(&memblock.memory, "memory");
  	memblock_dump(&memblock.reserved, "reserved");
  }

  void __init memblock_allow_resize(void)

  {

  	memblock_can_resize = 1;

  }

  static int __init early_memblock(char *p)
  {
  	if (p && strstr(p, "debug"))
  		memblock_debug = 1;
  	return 0;
  }
  early_param("memblock", early_memblock);

  #if defined(CONFIG_DEBUG_FS) && !defined(CONFIG_ARCH_DISCARD_MEMBLOCK)

  
  static int memblock_debug_show(struct seq_file *m, void *private)
  {
  	struct memblock_type *type = m->private;
  	struct memblock_region *reg;
  	int i;
  
  	for (i = 0; i < type->cnt; i++) {
  		reg = &type->regions[i];
  		seq_printf(m, "%4d: ", i);
  		if (sizeof(phys_addr_t) == 4)
  			seq_printf(m, "0x%08lx..0x%08lx
  ",
  				   (unsigned long)reg->base,
  				   (unsigned long)(reg->base + reg->size - 1));
  		else
  			seq_printf(m, "0x%016llx..0x%016llx
  ",
  				   (unsigned long long)reg->base,
  				   (unsigned long long)(reg->base + reg->size - 1));
  
  	}
  	return 0;
  }
  
  static int memblock_debug_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, memblock_debug_show, inode->i_private);
  }
  
  static const struct file_operations memblock_debug_fops = {
  	.open = memblock_debug_open,
  	.read = seq_read,
  	.llseek = seq_lseek,
  	.release = single_release,
  };
  
  static int __init memblock_init_debugfs(void)
  {
  	struct dentry *root = debugfs_create_dir("memblock", NULL);
  	if (!root)
  		return -ENXIO;
  	debugfs_create_file("memory", S_IRUGO, root, &memblock.memory, &memblock_debug_fops);
  	debugfs_create_file("reserved", S_IRUGO, root, &memblock.reserved, &memblock_debug_fops);
  
  	return 0;
  }
  __initcall(memblock_init_debugfs);
  
  #endif /* CONFIG_DEBUG_FS */