Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1885 insertions, 0 deletions

diff --git a/mm/memblock.c b/mm/memblock.c
new file mode 100644
index 000000000..4d471da3c
--- /dev/null
+++ b/mm/memblock.c
@@ -0,0 +1,1885 @@
+/*
+ * 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/kmemleak.h>
+#include <linux/seq_file.h>
+#include <linux/memblock.h>
+#include <linux/bootmem.h>
+
+#include <asm/sections.h>
+#include <linux/io.h>
+
+#include "internal.h"
+
+/**
+ * DOC: memblock overview
+ *
+ * Memblock is a method of managing memory regions during the early
+ * boot period when the usual kernel memory allocators are not up and
+ * running.
+ *
+ * Memblock views the system memory as collections of contiguous
+ * regions. There are several types of these collections:
+ *
+ * * ``memory`` - describes the physical memory available to the
+ *   kernel; this may differ from the actual physical memory installed
+ *   in the system, for instance when the memory is restricted with
+ *   ``mem=`` command line parameter
+ * * ``reserved`` - describes the regions that were allocated
+ * * ``physmap`` - describes the actual physical memory regardless of
+ *   the possible restrictions; the ``physmap`` type is only available
+ *   on some architectures.
+ *
+ * Each region is represented by :c:type:`struct memblock_region` that
+ * defines the region extents, its attributes and NUMA node id on NUMA
+ * systems. Every memory type is described by the :c:type:`struct
+ * memblock_type` which contains an array of memory regions along with
+ * the allocator metadata. The memory types are nicely wrapped with
+ * :c:type:`struct memblock`. This structure is statically initialzed
+ * at build time. The region arrays for the "memory" and "reserved"
+ * types are initially sized to %INIT_MEMBLOCK_REGIONS and for the
+ * "physmap" type to %INIT_PHYSMEM_REGIONS.
+ * The :c:func:`memblock_allow_resize` enables automatic resizing of
+ * the region arrays during addition of new regions. This feature
+ * should be used with care so that memory allocated for the region
+ * array will not overlap with areas that should be reserved, for
+ * example initrd.
+ *
+ * The early architecture setup should tell memblock what the physical
+ * memory layout is by using :c:func:`memblock_add` or
+ * :c:func:`memblock_add_node` functions. The first function does not
+ * assign the region to a NUMA node and it is appropriate for UMA
+ * systems. Yet, it is possible to use it on NUMA systems as well and
+ * assign the region to a NUMA node later in the setup process using
+ * :c:func:`memblock_set_node`. The :c:func:`memblock_add_node`
+ * performs such an assignment directly.
+ *
+ * Once memblock is setup the memory can be allocated using either
+ * memblock or bootmem APIs.
+ *
+ * As the system boot progresses, the architecture specific
+ * :c:func:`mem_init` function frees all the memory to the buddy page
+ * allocator.
+ *
+ * If an architecure enables %CONFIG_ARCH_DISCARD_MEMBLOCK, the
+ * memblock data structures will be discarded after the system
+ * initialization compltes.
+ */
+
+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;
+#ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
+static struct memblock_region memblock_physmem_init_regions[INIT_PHYSMEM_REGIONS] __initdata_memblock;
+#endif
+
+struct memblock memblock __initdata_memblock = {
+	.memory.regions		= memblock_memory_init_regions,
+	.memory.cnt		= 1,	/* empty dummy entry */
+	.memory.max		= INIT_MEMBLOCK_REGIONS,
+	.memory.name		= "memory",
+
+	.reserved.regions	= memblock_reserved_init_regions,
+	.reserved.cnt		= 1,	/* empty dummy entry */
+	.reserved.max		= INIT_MEMBLOCK_REGIONS,
+	.reserved.name		= "reserved",
+
+#ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
+	.physmem.regions	= memblock_physmem_init_regions,
+	.physmem.cnt		= 1,	/* empty dummy entry */
+	.physmem.max		= INIT_PHYSMEM_REGIONS,
+	.physmem.name		= "physmem",
+#endif
+
+	.bottom_up		= false,
+	.current_limit		= MEMBLOCK_ALLOC_ANYWHERE,
+};
+
+int memblock_debug __initdata_memblock;
+static bool system_has_some_mirror __initdata_memblock = false;
+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;
+
+enum memblock_flags __init_memblock choose_memblock_flags(void)
+{
+	return system_has_some_mirror ? MEMBLOCK_MIRROR : MEMBLOCK_NONE;
+}
+
+/* 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_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)));
+}
+
+bool __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++)
+		if (memblock_addrs_overlap(base, size, type->regions[i].base,
+					   type->regions[i].size))
+			break;
+	return i < type->cnt;
+}
+
+/**
+ * __memblock_find_range_bottom_up - find free area utility in bottom-up
+ * @start: start of candidate range
+ * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
+ *       %MEMBLOCK_ALLOC_ACCESSIBLE
+ * @size: size of free area to find
+ * @align: alignment of free area to find
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ * @flags: pick from blocks based on memory attributes
+ *
+ * Utility called from memblock_find_in_range_node(), find free area bottom-up.
+ *
+ * Return:
+ * Found address on success, 0 on failure.
+ */
+static phys_addr_t __init_memblock
+__memblock_find_range_bottom_up(phys_addr_t start, phys_addr_t end,
+				phys_addr_t size, phys_addr_t align, int nid,
+				enum memblock_flags flags)
+{
+	phys_addr_t this_start, this_end, cand;
+	u64 i;
+
+	for_each_free_mem_range(i, nid, flags, &this_start, &this_end, NULL) {
+		this_start = clamp(this_start, start, end);
+		this_end = clamp(this_end, start, end);
+
+		cand = round_up(this_start, align);
+		if (cand < this_end && this_end - cand >= size)
+			return cand;
+	}
+
+	return 0;
+}
+
+/**
+ * __memblock_find_range_top_down - find free area utility, in top-down
+ * @start: start of candidate range
+ * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
+ *       %MEMBLOCK_ALLOC_ACCESSIBLE
+ * @size: size of free area to find
+ * @align: alignment of free area to find
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ * @flags: pick from blocks based on memory attributes
+ *
+ * Utility called from memblock_find_in_range_node(), find free area top-down.
+ *
+ * Return:
+ * Found address on success, 0 on failure.
+ */
+static phys_addr_t __init_memblock
+__memblock_find_range_top_down(phys_addr_t start, phys_addr_t end,
+			       phys_addr_t size, phys_addr_t align, int nid,
+			       enum memblock_flags flags)
+{
+	phys_addr_t this_start, this_end, cand;
+	u64 i;
+
+	for_each_free_mem_range_reverse(i, nid, flags, &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_node - find free area in given range and node
+ * @size: size of free area to find
+ * @align: alignment of free area to find
+ * @start: start of candidate range
+ * @end: end of candidate range, can be %MEMBLOCK_ALLOC_ANYWHERE or
+ *       %MEMBLOCK_ALLOC_ACCESSIBLE
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ * @flags: pick from blocks based on memory attributes
+ *
+ * Find @size free area aligned to @align in the specified range and node.
+ *
+ * Return:
+ * Found address on success, 0 on failure.
+ */
+phys_addr_t __init_memblock memblock_find_in_range_node(phys_addr_t size,
+					phys_addr_t align, phys_addr_t start,
+					phys_addr_t end, int nid,
+					enum memblock_flags flags)
+{
+	/* 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);
+
+	if (memblock_bottom_up())
+		return __memblock_find_range_bottom_up(start, end, size, align,
+						       nid, flags);
+	else
+		return __memblock_find_range_top_down(start, end, size, align,
+						      nid, flags);
+}
+
+/**
+ * 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 or
+ *       %MEMBLOCK_ALLOC_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.
+ *
+ * Return:
+ * 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)
+{
+	phys_addr_t ret;
+	enum memblock_flags flags = choose_memblock_flags();
+
+again:
+	ret = memblock_find_in_range_node(size, align, start, end,
+					    NUMA_NO_NODE, flags);
+
+	if (!ret && (flags & MEMBLOCK_MIRROR)) {
+		pr_warn("Could not allocate %pap bytes of mirrored memory\n",
+			&size);
+		flags &= ~MEMBLOCK_MIRROR;
+		goto again;
+	}
+
+	return ret;
+}
+
+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;
+		type->regions[0].flags = 0;
+		memblock_set_region_node(&type->regions[0], MAX_NUMNODES);
+	}
+}
+
+#ifdef CONFIG_ARCH_DISCARD_MEMBLOCK
+/**
+ * memblock_discard - discard memory and reserved arrays if they were allocated
+ */
+void __init memblock_discard(void)
+{
+	phys_addr_t addr, size;
+
+	if (memblock.reserved.regions != memblock_reserved_init_regions) {
+		addr = __pa(memblock.reserved.regions);
+		size = PAGE_ALIGN(sizeof(struct memblock_region) *
+				  memblock.reserved.max);
+		if (memblock_reserved_in_slab)
+			kfree(memblock.reserved.regions);
+		else
+			__memblock_free_late(addr, size);
+	}
+
+	if (memblock.memory.regions != memblock_memory_init_regions) {
+		addr = __pa(memblock.memory.regions);
+		size = PAGE_ALIGN(sizeof(struct memblock_region) *
+				  memblock.memory.max);
+		if (memblock_memory_in_slab)
+			kfree(memblock.memory.regions);
+		else
+			__memblock_free_late(addr, size);
+	}
+}
+#endif
+
+/**
+ * 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.
+ *
+ * Return:
+ * 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, new_end;
+	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 !\n",
+		       type->name, type->max, type->max * 2);
+		return -1;
+	}
+
+	new_end = addr + new_size - 1;
+	memblock_dbg("memblock: %s is doubled to %ld at [%pa-%pa]",
+			type->name, type->max * 2, &addr, &new_end);
+
+	/*
+	 * 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) ||
+		    this->flags != next->flags) {
+			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
+ * @flags:	flags of the new region
+ *
+ * Insert new memblock region [@base, @base + @size) into @type at @idx.
+ * @type must already have extra room to accommodate 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,
+						   enum memblock_flags flags)
+{
+	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;
+	rgn->flags = flags;
+	memblock_set_region_node(rgn, nid);
+	type->cnt++;
+	type->total_size += size;
+}
+
+/**
+ * memblock_add_range - 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
+ * @flags: flags 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.
+ *
+ * Return:
+ * 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_add_range(struct memblock_type *type,
+				phys_addr_t base, phys_addr_t size,
+				int nid, enum memblock_flags flags)
+{
+	bool insert = false;
+	phys_addr_t obase = base;
+	phys_addr_t end = base + memblock_cap_size(base, &size);
+	int idx, nr_new;
+	struct memblock_region *rgn;
+
+	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;
+		type->regions[0].flags = flags;
+		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 accommodate the new area.  The second actually inserts them.
+	 */
+	base = obase;
+	nr_new = 0;
+
+	for_each_memblock_type(idx, type, rgn) {
+		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) {
+#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
+			WARN_ON(nid != memblock_get_region_node(rgn));
+#endif
+			WARN_ON(flags != rgn->flags);
+			nr_new++;
+			if (insert)
+				memblock_insert_region(type, idx++, base,
+						       rbase - base, nid,
+						       flags);
+		}
+		/* 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, idx, base, end - base,
+					       nid, flags);
+	}
+
+	if (!nr_new)
+		return 0;
+
+	/*
+	 * 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;
+	}
+}
+
+/**
+ * memblock_add_node - add new memblock region within a NUMA node
+ * @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) to the "memory"
+ * type. See memblock_add_range() description for mode details
+ *
+ * Return:
+ * 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_add_node(phys_addr_t base, phys_addr_t size,
+				       int nid)
+{
+	return memblock_add_range(&memblock.memory, base, size, nid, 0);
+}
+
+/**
+ * memblock_add - add new memblock region
+ * @base: base address of the new region
+ * @size: size of the new region
+ *
+ * Add new memblock region [@base, @base + @size) to the "memory"
+ * type. See memblock_add_range() description for mode details
+ *
+ * Return:
+ * 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
+{
+	phys_addr_t end = base + size - 1;
+
+	memblock_dbg("memblock_add: [%pa-%pa] %pF\n",
+		     &base, &end, (void *)_RET_IP_);
+
+	return memblock_add_range(&memblock.memory, base, size, MAX_NUMNODES, 0);
+}
+
+/**
+ * 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.
+ *
+ * Return:
+ * 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 idx;
+	struct memblock_region *rgn;
+
+	*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_each_memblock_type(idx, type, rgn) {
+		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, idx, rbase, base - rbase,
+					       memblock_get_region_node(rgn),
+					       rgn->flags);
+		} 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, idx--, rbase, end - rbase,
+					       memblock_get_region_node(rgn),
+					       rgn->flags);
+		} else {
+			/* @rgn is fully contained, record it */
+			if (!*end_rgn)
+				*start_rgn = idx;
+			*end_rgn = idx + 1;
+		}
+	}
+
+	return 0;
+}
+
+static int __init_memblock memblock_remove_range(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)
+{
+	phys_addr_t end = base + size - 1;
+
+	memblock_dbg("memblock_remove: [%pa-%pa] %pS\n",
+		     &base, &end, (void *)_RET_IP_);
+
+	return memblock_remove_range(&memblock.memory, base, size);
+}
+
+
+int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
+{
+	phys_addr_t end = base + size - 1;
+
+	memblock_dbg("   memblock_free: [%pa-%pa] %pF\n",
+		     &base, &end, (void *)_RET_IP_);
+
+	kmemleak_free_part_phys(base, size);
+	return memblock_remove_range(&memblock.reserved, base, size);
+}
+
+int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
+{
+	phys_addr_t end = base + size - 1;
+
+	memblock_dbg("memblock_reserve: [%pa-%pa] %pF\n",
+		     &base, &end, (void *)_RET_IP_);
+
+	return memblock_add_range(&memblock.reserved, base, size, MAX_NUMNODES, 0);
+}
+
+/**
+ * memblock_setclr_flag - set or clear flag for a memory region
+ * @base: base address of the region
+ * @size: size of the region
+ * @set: set or clear the flag
+ * @flag: the flag to udpate
+ *
+ * This function isolates region [@base, @base + @size), and sets/clears flag
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+static int __init_memblock memblock_setclr_flag(phys_addr_t base,
+				phys_addr_t size, int set, int flag)
+{
+	struct memblock_type *type = &memblock.memory;
+	int i, ret, start_rgn, end_rgn;
+
+	ret = memblock_isolate_range(type, base, size, &start_rgn, &end_rgn);
+	if (ret)
+		return ret;
+
+	for (i = start_rgn; i < end_rgn; i++)
+		if (set)
+			memblock_set_region_flags(&type->regions[i], flag);
+		else
+			memblock_clear_region_flags(&type->regions[i], flag);
+
+	memblock_merge_regions(type);
+	return 0;
+}
+
+/**
+ * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
+{
+	return memblock_setclr_flag(base, size, 1, MEMBLOCK_HOTPLUG);
+}
+
+/**
+ * memblock_clear_hotplug - Clear flag MEMBLOCK_HOTPLUG for a specified region.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
+{
+	return memblock_setclr_flag(base, size, 0, MEMBLOCK_HOTPLUG);
+}
+
+/**
+ * memblock_mark_mirror - Mark mirrored memory with flag MEMBLOCK_MIRROR.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
+{
+	system_has_some_mirror = true;
+
+	return memblock_setclr_flag(base, size, 1, MEMBLOCK_MIRROR);
+}
+
+/**
+ * memblock_mark_nomap - Mark a memory region with flag MEMBLOCK_NOMAP.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size)
+{
+	return memblock_setclr_flag(base, size, 1, MEMBLOCK_NOMAP);
+}
+
+/**
+ * memblock_clear_nomap - Clear flag MEMBLOCK_NOMAP for a specified region.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_clear_nomap(phys_addr_t base, phys_addr_t size)
+{
+	return memblock_setclr_flag(base, size, 0, MEMBLOCK_NOMAP);
+}
+
+/**
+ * __next_reserved_mem_region - next function for for_each_reserved_region()
+ * @idx: pointer to u64 loop variable
+ * @out_start: ptr to phys_addr_t for start address of the region, can be %NULL
+ * @out_end: ptr to phys_addr_t for end address of the region, can be %NULL
+ *
+ * Iterate over all reserved memory regions.
+ */
+void __init_memblock __next_reserved_mem_region(u64 *idx,
+					   phys_addr_t *out_start,
+					   phys_addr_t *out_end)
+{
+	struct memblock_type *type = &memblock.reserved;
+
+	if (*idx < type->cnt) {
+		struct memblock_region *r = &type->regions[*idx];
+		phys_addr_t base = r->base;
+		phys_addr_t size = r->size;
+
+		if (out_start)
+			*out_start = base;
+		if (out_end)
+			*out_end = base + size - 1;
+
+		*idx += 1;
+		return;
+	}
+
+	/* signal end of iteration */
+	*idx = ULLONG_MAX;
+}
+
+/**
+ * __next__mem_range - next function for for_each_free_mem_range() etc.
+ * @idx: pointer to u64 loop variable
+ * @nid: node selector, %NUMA_NO_NODE for all nodes
+ * @flags: pick from blocks based on memory attributes
+ * @type_a: pointer to memblock_type from where the range is taken
+ * @type_b: pointer to memblock_type which excludes memory from being taken
+ * @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 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 type_a and the upper 32bit indexes the
+ * areas before each region in type_b.	For example, if type_b 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_mem_range(u64 *idx, int nid,
+				      enum memblock_flags flags,
+				      struct memblock_type *type_a,
+				      struct memblock_type *type_b,
+				      phys_addr_t *out_start,
+				      phys_addr_t *out_end, int *out_nid)
+{
+	int idx_a = *idx & 0xffffffff;
+	int idx_b = *idx >> 32;
+
+	if (WARN_ONCE(nid == MAX_NUMNODES,
+	"Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
+		nid = NUMA_NO_NODE;
+
+	for (; idx_a < type_a->cnt; idx_a++) {
+		struct memblock_region *m = &type_a->regions[idx_a];
+
+		phys_addr_t m_start = m->base;
+		phys_addr_t m_end = m->base + m->size;
+		int	    m_nid = memblock_get_region_node(m);
+
+		/* only memory regions are associated with nodes, check it */
+		if (nid != NUMA_NO_NODE && nid != m_nid)
+			continue;
+
+		/* skip hotpluggable memory regions if needed */
+		if (movable_node_is_enabled() && memblock_is_hotpluggable(m))
+			continue;
+
+		/* if we want mirror memory skip non-mirror memory regions */
+		if ((flags & MEMBLOCK_MIRROR) && !memblock_is_mirror(m))
+			continue;
+
+		/* skip nomap memory unless we were asked for it explicitly */
+		if (!(flags & MEMBLOCK_NOMAP) && memblock_is_nomap(m))
+			continue;
+
+		if (!type_b) {
+			if (out_start)
+				*out_start = m_start;
+			if (out_end)
+				*out_end = m_end;
+			if (out_nid)
+				*out_nid = m_nid;
+			idx_a++;
+			*idx = (u32)idx_a | (u64)idx_b << 32;
+			return;
+		}
+
+		/* scan areas before each reservation */
+		for (; idx_b < type_b->cnt + 1; idx_b++) {
+			struct memblock_region *r;
+			phys_addr_t r_start;
+			phys_addr_t r_end;
+
+			r = &type_b->regions[idx_b];
+			r_start = idx_b ? r[-1].base + r[-1].size : 0;
+			r_end = idx_b < type_b->cnt ?
+				r->base : PHYS_ADDR_MAX;
+
+			/*
+			 * if idx_b advanced past idx_a,
+			 * break out to advance idx_a
+			 */
+			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 = m_nid;
+				/*
+				 * The region which ends first is
+				 * advanced for the next iteration.
+				 */
+				if (m_end <= r_end)
+					idx_a++;
+				else
+					idx_b++;
+				*idx = (u32)idx_a | (u64)idx_b << 32;
+				return;
+			}
+		}
+	}
+
+	/* signal end of iteration */
+	*idx = ULLONG_MAX;
+}
+
+/**
+ * __next_mem_range_rev - generic next function for for_each_*_range_rev()
+ *
+ * @idx: pointer to u64 loop variable
+ * @nid: node selector, %NUMA_NO_NODE for all nodes
+ * @flags: pick from blocks based on memory attributes
+ * @type_a: pointer to memblock_type from where the range is taken
+ * @type_b: pointer to memblock_type which excludes memory from being taken
+ * @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
+ *
+ * Finds the next range from type_a which is not marked as unsuitable
+ * in type_b.
+ *
+ * Reverse of __next_mem_range().
+ */
+void __init_memblock __next_mem_range_rev(u64 *idx, int nid,
+					  enum memblock_flags flags,
+					  struct memblock_type *type_a,
+					  struct memblock_type *type_b,
+					  phys_addr_t *out_start,
+					  phys_addr_t *out_end, int *out_nid)
+{
+	int idx_a = *idx & 0xffffffff;
+	int idx_b = *idx >> 32;
+
+	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
+		nid = NUMA_NO_NODE;
+
+	if (*idx == (u64)ULLONG_MAX) {
+		idx_a = type_a->cnt - 1;
+		if (type_b != NULL)
+			idx_b = type_b->cnt;
+		else
+			idx_b = 0;
+	}
+
+	for (; idx_a >= 0; idx_a--) {
+		struct memblock_region *m = &type_a->regions[idx_a];
+
+		phys_addr_t m_start = m->base;
+		phys_addr_t m_end = m->base + m->size;
+		int m_nid = memblock_get_region_node(m);
+
+		/* only memory regions are associated with nodes, check it */
+		if (nid != NUMA_NO_NODE && nid != m_nid)
+			continue;
+
+		/* skip hotpluggable memory regions if needed */
+		if (movable_node_is_enabled() && memblock_is_hotpluggable(m))
+			continue;
+
+		/* if we want mirror memory skip non-mirror memory regions */
+		if ((flags & MEMBLOCK_MIRROR) && !memblock_is_mirror(m))
+			continue;
+
+		/* skip nomap memory unless we were asked for it explicitly */
+		if (!(flags & MEMBLOCK_NOMAP) && memblock_is_nomap(m))
+			continue;
+
+		if (!type_b) {
+			if (out_start)
+				*out_start = m_start;
+			if (out_end)
+				*out_end = m_end;
+			if (out_nid)
+				*out_nid = m_nid;
+			idx_a--;
+			*idx = (u32)idx_a | (u64)idx_b << 32;
+			return;
+		}
+
+		/* scan areas before each reservation */
+		for (; idx_b >= 0; idx_b--) {
+			struct memblock_region *r;
+			phys_addr_t r_start;
+			phys_addr_t r_end;
+
+			r = &type_b->regions[idx_b];
+			r_start = idx_b ? r[-1].base + r[-1].size : 0;
+			r_end = idx_b < type_b->cnt ?
+				r->base : PHYS_ADDR_MAX;
+			/*
+			 * if idx_b advanced past idx_a,
+			 * break out to advance idx_a
+			 */
+
+			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 = m_nid;
+				if (m_start >= r_start)
+					idx_a--;
+				else
+					idx_b--;
+				*idx = (u32)idx_a | (u64)idx_b << 32;
+				return;
+			}
+		}
+	}
+	/* signal end of iteration */
+	*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
+ * @type: memblock type to set node ID for
+ * @nid: node ID to set
+ *
+ * Set the nid of memblock @type regions in [@base, @base + @size) to @nid.
+ * Regions which cross the area boundaries are split as necessary.
+ *
+ * Return:
+ * 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_set_node(phys_addr_t base, phys_addr_t size,
+				      struct memblock_type *type, int nid)
+{
+	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_range_nid(phys_addr_t size,
+					phys_addr_t align, phys_addr_t start,
+					phys_addr_t end, int nid,
+					enum memblock_flags flags)
+{
+	phys_addr_t found;
+
+	if (!align)
+		align = SMP_CACHE_BYTES;
+
+	found = memblock_find_in_range_node(size, align, start, end, nid,
+					    flags);
+	if (found && !memblock_reserve(found, size)) {
+		/*
+		 * The min_count is set to 0 so that memblock allocations are
+		 * never reported as leaks.
+		 */
+		kmemleak_alloc_phys(found, size, 0, 0);
+		return found;
+	}
+	return 0;
+}
+
+phys_addr_t __init memblock_alloc_range(phys_addr_t size, phys_addr_t align,
+					phys_addr_t start, phys_addr_t end,
+					enum memblock_flags flags)
+{
+	return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
+					flags);
+}
+
+phys_addr_t __init memblock_alloc_base_nid(phys_addr_t size,
+					phys_addr_t align, phys_addr_t max_addr,
+					int nid, enum memblock_flags flags)
+{
+	return memblock_alloc_range_nid(size, align, 0, max_addr, nid, flags);
+}
+
+phys_addr_t __init memblock_alloc_nid(phys_addr_t size, phys_addr_t align, int nid)
+{
+	enum memblock_flags flags = choose_memblock_flags();
+	phys_addr_t ret;
+
+again:
+	ret = memblock_alloc_base_nid(size, align, MEMBLOCK_ALLOC_ACCESSIBLE,
+				      nid, flags);
+
+	if (!ret && (flags & MEMBLOCK_MIRROR)) {
+		flags &= ~MEMBLOCK_MIRROR;
+		goto again;
+	}
+	return ret;
+}
+
+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, NUMA_NO_NODE,
+				       MEMBLOCK_NONE);
+}
+
+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 %pa bytes below %pa.\n",
+		      &size, &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);
+}
+
+#if defined(CONFIG_NO_BOOTMEM)
+/**
+ * memblock_virt_alloc_internal - allocate boot memory block
+ * @size: size of memory block to be allocated in bytes
+ * @align: alignment of the region and block's size
+ * @min_addr: the lower bound of the memory region to allocate (phys address)
+ * @max_addr: the upper bound of the memory region to allocate (phys address)
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ *
+ * The @min_addr limit is dropped if it can not be satisfied and the allocation
+ * will fall back to memory below @min_addr. Also, allocation may fall back
+ * to any node in the system if the specified node can not
+ * hold the requested memory.
+ *
+ * The allocation is performed from memory region limited by
+ * memblock.current_limit if @max_addr == %BOOTMEM_ALLOC_ACCESSIBLE.
+ *
+ * The memory block is aligned on %SMP_CACHE_BYTES if @align == 0.
+ *
+ * The phys address of allocated boot memory block is converted to virtual and
+ * allocated memory is reset to 0.
+ *
+ * In addition, function sets the min_count to 0 using kmemleak_alloc for
+ * allocated boot memory block, so that it is never reported as leaks.
+ *
+ * Return:
+ * Virtual address of allocated memory block on success, NULL on failure.
+ */
+static void * __init memblock_virt_alloc_internal(
+				phys_addr_t size, phys_addr_t align,
+				phys_addr_t min_addr, phys_addr_t max_addr,
+				int nid)
+{
+	phys_addr_t alloc;
+	void *ptr;
+	enum memblock_flags flags = choose_memblock_flags();
+
+	if (WARN_ONCE(nid == MAX_NUMNODES, "Usage of MAX_NUMNODES is deprecated. Use NUMA_NO_NODE instead\n"))
+		nid = NUMA_NO_NODE;
+
+	/*
+	 * Detect any accidental use of these APIs after slab is ready, as at
+	 * this moment memblock may be deinitialized already and its
+	 * internal data may be destroyed (after execution of free_all_bootmem)
+	 */
+	if (WARN_ON_ONCE(slab_is_available()))
+		return kzalloc_node(size, GFP_NOWAIT, nid);
+
+	if (!align)
+		align = SMP_CACHE_BYTES;
+
+	if (max_addr > memblock.current_limit)
+		max_addr = memblock.current_limit;
+again:
+	alloc = memblock_find_in_range_node(size, align, min_addr, max_addr,
+					    nid, flags);
+	if (alloc && !memblock_reserve(alloc, size))
+		goto done;
+
+	if (nid != NUMA_NO_NODE) {
+		alloc = memblock_find_in_range_node(size, align, min_addr,
+						    max_addr, NUMA_NO_NODE,
+						    flags);
+		if (alloc && !memblock_reserve(alloc, size))
+			goto done;
+	}
+
+	if (min_addr) {
+		min_addr = 0;
+		goto again;
+	}
+
+	if (flags & MEMBLOCK_MIRROR) {
+		flags &= ~MEMBLOCK_MIRROR;
+		pr_warn("Could not allocate %pap bytes of mirrored memory\n",
+			&size);
+		goto again;
+	}
+
+	return NULL;
+done:
+	ptr = phys_to_virt(alloc);
+
+	/*
+	 * The min_count is set to 0 so that bootmem allocated blocks
+	 * are never reported as leaks. This is because many of these blocks
+	 * are only referred via the physical address which is not
+	 * looked up by kmemleak.
+	 */
+	kmemleak_alloc(ptr, size, 0, 0);
+
+	return ptr;
+}
+
+/**
+ * memblock_virt_alloc_try_nid_raw - allocate boot memory block without zeroing
+ * memory and without panicking
+ * @size: size of memory block to be allocated in bytes
+ * @align: alignment of the region and block's size
+ * @min_addr: the lower bound of the memory region from where the allocation
+ *	  is preferred (phys address)
+ * @max_addr: the upper bound of the memory region from where the allocation
+ *	      is preferred (phys address), or %BOOTMEM_ALLOC_ACCESSIBLE to
+ *	      allocate only from memory limited by memblock.current_limit value
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ *
+ * Public function, provides additional debug information (including caller
+ * info), if enabled. Does not zero allocated memory, does not panic if request
+ * cannot be satisfied.
+ *
+ * Return:
+ * Virtual address of allocated memory block on success, NULL on failure.
+ */
+void * __init memblock_virt_alloc_try_nid_raw(
+			phys_addr_t size, phys_addr_t align,
+			phys_addr_t min_addr, phys_addr_t max_addr,
+			int nid)
+{
+	void *ptr;
+
+	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pF\n",
+		     __func__, (u64)size, (u64)align, nid, &min_addr,
+		     &max_addr, (void *)_RET_IP_);
+
+	ptr = memblock_virt_alloc_internal(size, align,
+					   min_addr, max_addr, nid);
+#ifdef CONFIG_DEBUG_VM
+	if (ptr && size > 0)
+		memset(ptr, PAGE_POISON_PATTERN, size);
+#endif
+	return ptr;
+}
+
+/**
+ * memblock_virt_alloc_try_nid_nopanic - allocate boot memory block
+ * @size: size of memory block to be allocated in bytes
+ * @align: alignment of the region and block's size
+ * @min_addr: the lower bound of the memory region from where the allocation
+ *	  is preferred (phys address)
+ * @max_addr: the upper bound of the memory region from where the allocation
+ *	      is preferred (phys address), or %BOOTMEM_ALLOC_ACCESSIBLE to
+ *	      allocate only from memory limited by memblock.current_limit value
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ *
+ * Public function, provides additional debug information (including caller
+ * info), if enabled. This function zeroes the allocated memory.
+ *
+ * Return:
+ * Virtual address of allocated memory block on success, NULL on failure.
+ */
+void * __init memblock_virt_alloc_try_nid_nopanic(
+				phys_addr_t size, phys_addr_t align,
+				phys_addr_t min_addr, phys_addr_t max_addr,
+				int nid)
+{
+	void *ptr;
+
+	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pF\n",
+		     __func__, (u64)size, (u64)align, nid, &min_addr,
+		     &max_addr, (void *)_RET_IP_);
+
+	ptr = memblock_virt_alloc_internal(size, align,
+					   min_addr, max_addr, nid);
+	if (ptr)
+		memset(ptr, 0, size);
+	return ptr;
+}
+
+/**
+ * memblock_virt_alloc_try_nid - allocate boot memory block with panicking
+ * @size: size of memory block to be allocated in bytes
+ * @align: alignment of the region and block's size
+ * @min_addr: the lower bound of the memory region from where the allocation
+ *	  is preferred (phys address)
+ * @max_addr: the upper bound of the memory region from where the allocation
+ *	      is preferred (phys address), or %BOOTMEM_ALLOC_ACCESSIBLE to
+ *	      allocate only from memory limited by memblock.current_limit value
+ * @nid: nid of the free area to find, %NUMA_NO_NODE for any node
+ *
+ * Public panicking version of memblock_virt_alloc_try_nid_nopanic()
+ * which provides debug information (including caller info), if enabled,
+ * and panics if the request can not be satisfied.
+ *
+ * Return:
+ * Virtual address of allocated memory block on success, NULL on failure.
+ */
+void * __init memblock_virt_alloc_try_nid(
+			phys_addr_t size, phys_addr_t align,
+			phys_addr_t min_addr, phys_addr_t max_addr,
+			int nid)
+{
+	void *ptr;
+
+	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pF\n",
+		     __func__, (u64)size, (u64)align, nid, &min_addr,
+		     &max_addr, (void *)_RET_IP_);
+	ptr = memblock_virt_alloc_internal(size, align,
+					   min_addr, max_addr, nid);
+	if (ptr) {
+		memset(ptr, 0, size);
+		return ptr;
+	}
+
+	panic("%s: Failed to allocate %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa\n",
+	      __func__, (u64)size, (u64)align, nid, &min_addr, &max_addr);
+	return NULL;
+}
+#endif
+
+/**
+ * __memblock_free_early - free boot memory block
+ * @base: phys starting address of the  boot memory block
+ * @size: size of the boot memory block in bytes
+ *
+ * Free boot memory block previously allocated by memblock_virt_alloc_xx() API.
+ * The freeing memory will not be released to the buddy allocator.
+ */
+void __init __memblock_free_early(phys_addr_t base, phys_addr_t size)
+{
+	memblock_free(base, size);
+}
+
+/**
+ * __memblock_free_late - free bootmem block pages directly to buddy allocator
+ * @base: phys starting address of the  boot memory block
+ * @size: size of the boot memory block in bytes
+ *
+ * This is only useful when the bootmem allocator has already been torn
+ * down, but we are still initializing the system.  Pages are released directly
+ * to the buddy allocator, no bootmem metadata is updated because it is gone.
+ */
+void __init __memblock_free_late(phys_addr_t base, phys_addr_t size)
+{
+	phys_addr_t cursor, end;
+
+	end = base + size - 1;
+	memblock_dbg("%s: [%pa-%pa] %pF\n",
+		     __func__, &base, &end, (void *)_RET_IP_);
+	kmemleak_free_part_phys(base, size);
+	cursor = PFN_UP(base);
+	end = PFN_DOWN(base + size);
+
+	for (; cursor < end; cursor++) {
+		__free_pages_bootmem(pfn_to_page(cursor), cursor, 0);
+		totalram_pages++;
+	}
+}
+
+/*
+ * Remaining API functions
+ */
+
+phys_addr_t __init_memblock memblock_phys_mem_size(void)
+{
+	return memblock.memory.total_size;
+}
+
+phys_addr_t __init_memblock memblock_reserved_size(void)
+{
+	return memblock.reserved.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 PFN_PHYS(pages);
+}
+
+/* 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);
+}
+
+static phys_addr_t __init_memblock __find_max_addr(phys_addr_t limit)
+{
+	phys_addr_t max_addr = PHYS_ADDR_MAX;
+	struct memblock_region *r;
+
+	/*
+	 * translate the memory @limit size into the max address within one of
+	 * the memory memblock regions, if the @limit exceeds the total size
+	 * of those regions, max_addr will keep original value PHYS_ADDR_MAX
+	 */
+	for_each_memblock(memory, r) {
+		if (limit <= r->size) {
+			max_addr = r->base + limit;
+			break;
+		}
+		limit -= r->size;
+	}
+
+	return max_addr;
+}
+
+void __init memblock_enforce_memory_limit(phys_addr_t limit)
+{
+	phys_addr_t max_addr = PHYS_ADDR_MAX;
+
+	if (!limit)
+		return;
+
+	max_addr = __find_max_addr(limit);
+
+	/* @limit exceeds the total size of the memory, do nothing */
+	if (max_addr == PHYS_ADDR_MAX)
+		return;
+
+	/* truncate both memory and reserved regions */
+	memblock_remove_range(&memblock.memory, max_addr,
+			      PHYS_ADDR_MAX);
+	memblock_remove_range(&memblock.reserved, max_addr,
+			      PHYS_ADDR_MAX);
+}
+
+void __init memblock_cap_memory_range(phys_addr_t base, phys_addr_t size)
+{
+	int start_rgn, end_rgn;
+	int i, ret;
+
+	if (!size)
+		return;
+
+	ret = memblock_isolate_range(&memblock.memory, base, size,
+						&start_rgn, &end_rgn);
+	if (ret)
+		return;
+
+	/* remove all the MAP regions */
+	for (i = memblock.memory.cnt - 1; i >= end_rgn; i--)
+		if (!memblock_is_nomap(&memblock.memory.regions[i]))
+			memblock_remove_region(&memblock.memory, i);
+
+	for (i = start_rgn - 1; i >= 0; i--)
+		if (!memblock_is_nomap(&memblock.memory.regions[i]))
+			memblock_remove_region(&memblock.memory, i);
+
+	/* truncate the reserved regions */
+	memblock_remove_range(&memblock.reserved, 0, base);
+	memblock_remove_range(&memblock.reserved,
+			base + size, PHYS_ADDR_MAX);
+}
+
+void __init memblock_mem_limit_remove_map(phys_addr_t limit)
+{
+	phys_addr_t max_addr;
+
+	if (!limit)
+		return;
+
+	max_addr = __find_max_addr(limit);
+
+	/* @limit exceeds the total size of the memory, do nothing */
+	if (max_addr == PHYS_ADDR_MAX)
+		return;
+
+	memblock_cap_memory_range(0, max_addr);
+}
+
+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;
+}
+
+bool __init memblock_is_reserved(phys_addr_t addr)
+{
+	return memblock_search(&memblock.reserved, addr) != -1;
+}
+
+bool __init_memblock memblock_is_memory(phys_addr_t addr)
+{
+	return memblock_search(&memblock.memory, addr) != -1;
+}
+
+bool __init_memblock memblock_is_map_memory(phys_addr_t addr)
+{
+	int i = memblock_search(&memblock.memory, addr);
+
+	if (i == -1)
+		return false;
+	return !memblock_is_nomap(&memblock.memory.regions[i]);
+}
+
+#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
+int __init_memblock memblock_search_pfn_nid(unsigned long pfn,
+			 unsigned long *start_pfn, unsigned long *end_pfn)
+{
+	struct memblock_type *type = &memblock.memory;
+	int mid = memblock_search(type, PFN_PHYS(pfn));
+
+	if (mid == -1)
+		return -1;
+
+	*start_pfn = PFN_DOWN(type->regions[mid].base);
+	*end_pfn = PFN_DOWN(type->regions[mid].base + type->regions[mid].size);
+
+	return type->regions[mid].nid;
+}
+#endif
+
+/**
+ * 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.
+ *
+ * Return:
+ * 0 if false, non-zero if true
+ */
+bool __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 false;
+	return (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.
+ *
+ * Return:
+ * True if they intersect, false if not.
+ */
+bool __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);
+}
+
+void __init_memblock memblock_trim_memory(phys_addr_t align)
+{
+	phys_addr_t start, end, orig_start, orig_end;
+	struct memblock_region *r;
+
+	for_each_memblock(memory, r) {
+		orig_start = r->base;
+		orig_end = r->base + r->size;
+		start = round_up(orig_start, align);
+		end = round_down(orig_end, align);
+
+		if (start == orig_start && end == orig_end)
+			continue;
+
+		if (start < end) {
+			r->base = start;
+			r->size = end - start;
+		} else {
+			memblock_remove_region(&memblock.memory,
+					       r - memblock.memory.regions);
+			r--;
+		}
+	}
+}
+
+void __init_memblock memblock_set_current_limit(phys_addr_t limit)
+{
+	memblock.current_limit = limit;
+}
+
+phys_addr_t __init_memblock memblock_get_current_limit(void)
+{
+	return memblock.current_limit;
+}
+
+static void __init_memblock memblock_dump(struct memblock_type *type)
+{
+	phys_addr_t base, end, size;
+	enum memblock_flags flags;
+	int idx;
+	struct memblock_region *rgn;
+
+	pr_info(" %s.cnt  = 0x%lx\n", type->name, type->cnt);
+
+	for_each_memblock_type(idx, type, rgn) {
+		char nid_buf[32] = "";
+
+		base = rgn->base;
+		size = rgn->size;
+		end = base + size - 1;
+		flags = rgn->flags;
+#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[%pa-%pa], %pa bytes%s flags: %#x\n",
+			type->name, idx, &base, &end, &size, nid_buf, flags);
+	}
+}
+
+void __init_memblock __memblock_dump_all(void)
+{
+	pr_info("MEMBLOCK configuration:\n");
+	pr_info(" memory size = %pa reserved size = %pa\n",
+		&memblock.memory.total_size,
+		&memblock.reserved.total_size);
+
+	memblock_dump(&memblock.memory);
+	memblock_dump(&memblock.reserved);
+#ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
+	memblock_dump(&memblock.physmem);
+#endif
+}
+
+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;
+	phys_addr_t end;
+
+	for (i = 0; i < type->cnt; i++) {
+		reg = &type->regions[i];
+		end = reg->base + reg->size - 1;
+
+		seq_printf(m, "%4d: ", i);
+		seq_printf(m, "%pa..%pa\n", &reg->base, &end);
+	}
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(memblock_debug);
+
+static int __init memblock_init_debugfs(void)
+{
+	struct dentry *root = debugfs_create_dir("memblock", NULL);
+	if (!root)
+		return -ENXIO;
+	debugfs_create_file("memory", 0444, root,
+			    &memblock.memory, &memblock_debug_fops);
+	debugfs_create_file("reserved", 0444, root,
+			    &memblock.reserved, &memblock_debug_fops);
+#ifdef CONFIG_HAVE_MEMBLOCK_PHYS_MAP
+	debugfs_create_file("physmem", 0444, root,
+			    &memblock.physmem, &memblock_debug_fops);
+#endif
+
+	return 0;
+}
+__initcall(memblock_init_debugfs);
+
+#endif /* CONFIG_DEBUG_FS */