1 files changed, 514 insertions, 421 deletions

diff --git a/mm/bootmem.c b/mm/bootmem.c
index 8d9f60e06f62..4af15d0340ad 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -1,12 +1,12 @@
 /*
- *  linux/mm/bootmem.c
+ *  bootmem - A boot-time physical memory allocator and configurator
  *
  *  Copyright (C) 1999 Ingo Molnar
- *  Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
+ *                1999 Kanoj Sarcar, SGI
+ *                2008 Johannes Weiner
  *
- *  simple boot-time physical memory area allocator and
- *  free memory collector. It's used to deal with reserved
- *  system memory and memory holes as well.
+ * Access to this subsystem has to be serialized externally (which is true
+ * for the boot process anyway).
  */
 #include <linux/init.h>
 #include <linux/pfn.h>
@@ -19,15 +19,10 @@
 
 #include "internal.h"
 
-/*
- * Access to this subsystem has to be serialized externally. (this is
- * true for the boot process anyway)
- */
 unsigned long max_low_pfn;
 unsigned long min_low_pfn;
 unsigned long max_pfn;
 
-static LIST_HEAD(bdata_list);
 #ifdef CONFIG_CRASH_DUMP
 /*
  * If we have booted due to a crash, max_pfn will be a very low value. We need
@@ -36,63 +31,72 @@ static LIST_HEAD(bdata_list);
 unsigned long saved_max_pfn;
 #endif
 
-/* return the number of _pages_ that will be allocated for the boot bitmap */
-unsigned long __init bootmem_bootmap_pages(unsigned long pages)
+bootmem_data_t bootmem_node_data[MAX_NUMNODES] __initdata;
+
+static struct list_head bdata_list __initdata = LIST_HEAD_INIT(bdata_list);
+
+static int bootmem_debug;
+
+static int __init bootmem_debug_setup(char *buf)
 {
-	unsigned long mapsize;
+	bootmem_debug = 1;
+	return 0;
+}
+early_param("bootmem_debug", bootmem_debug_setup);
 
-	mapsize = (pages+7)/8;
-	mapsize = (mapsize + ~PAGE_MASK) & PAGE_MASK;
-	mapsize >>= PAGE_SHIFT;
+#define bdebug(fmt, args...) ({				\
+	if (unlikely(bootmem_debug))			\
+		printk(KERN_INFO			\
+			"bootmem::%s " fmt,		\
+			__FUNCTION__, ## args);		\
+})
 
-	return mapsize;
+static unsigned long __init bootmap_bytes(unsigned long pages)
+{
+	unsigned long bytes = (pages + 7) / 8;
+
+	return ALIGN(bytes, sizeof(long));
 }
 
-/*
- * link bdata in order
+/**
+ * bootmem_bootmap_pages - calculate bitmap size in pages
+ * @pages: number of pages the bitmap has to represent
  */
-static void __init link_bootmem(bootmem_data_t *bdata)
+unsigned long __init bootmem_bootmap_pages(unsigned long pages)
 {
-	bootmem_data_t *ent;
+	unsigned long bytes = bootmap_bytes(pages);
 
-	if (list_empty(&bdata_list)) {
-		list_add(&bdata->list, &bdata_list);
-		return;
-	}
-	/* insert in order */
-	list_for_each_entry(ent, &bdata_list, list) {
-		if (bdata->node_boot_start < ent->node_boot_start) {
-			list_add_tail(&bdata->list, &ent->list);
-			return;
-		}
-	}
-	list_add_tail(&bdata->list, &bdata_list);
+	return PAGE_ALIGN(bytes) >> PAGE_SHIFT;
 }
 
 /*
- * Given an initialised bdata, it returns the size of the boot bitmap
+ * link bdata in order
  */
-static unsigned long __init get_mapsize(bootmem_data_t *bdata)
+static void __init link_bootmem(bootmem_data_t *bdata)
 {
-	unsigned long mapsize;
-	unsigned long start = PFN_DOWN(bdata->node_boot_start);
-	unsigned long end = bdata->node_low_pfn;
+	struct list_head *iter;
 
-	mapsize = ((end - start) + 7) / 8;
-	return ALIGN(mapsize, sizeof(long));
+	list_for_each(iter, &bdata_list) {
+		bootmem_data_t *ent;
+
+		ent = list_entry(iter, bootmem_data_t, list);
+		if (bdata->node_min_pfn < ent->node_min_pfn)
+			break;
+	}
+	list_add_tail(&bdata->list, iter);
 }
 
 /*
  * Called once to set up the allocator itself.
  */
-static unsigned long __init init_bootmem_core(pg_data_t *pgdat,
+static unsigned long __init init_bootmem_core(bootmem_data_t *bdata,
 	unsigned long mapstart, unsigned long start, unsigned long end)
 {
-	bootmem_data_t *bdata = pgdat->bdata;
 	unsigned long mapsize;
 
+	mminit_validate_memmodel_limits(&start, &end);
 	bdata->node_bootmem_map = phys_to_virt(PFN_PHYS(mapstart));
-	bdata->node_boot_start = PFN_PHYS(start);
+	bdata->node_min_pfn = start;
 	bdata->node_low_pfn = end;
 	link_bootmem(bdata);
 
@@ -100,429 +104,461 @@ static unsigned long __init init_bootmem_core(pg_data_t *pgdat,
 	 * Initially all pages are reserved - setup_arch() has to
 	 * register free RAM areas explicitly.
 	 */
-	mapsize = get_mapsize(bdata);
+	mapsize = bootmap_bytes(end - start);
 	memset(bdata->node_bootmem_map, 0xff, mapsize);
 
+	bdebug("nid=%td start=%lx map=%lx end=%lx mapsize=%lx\n",
+		bdata - bootmem_node_data, start, mapstart, end, mapsize);
+
 	return mapsize;
 }
 
-/*
- * Marks a particular physical memory range as unallocatable. Usable RAM
- * might be used for boot-time allocations - or it might get added
- * to the free page pool later on.
+/**
+ * init_bootmem_node - register a node as boot memory
+ * @pgdat: node to register
+ * @freepfn: pfn where the bitmap for this node is to be placed
+ * @startpfn: first pfn on the node
+ * @endpfn: first pfn after the node
+ *
+ * Returns the number of bytes needed to hold the bitmap for this node.
  */
-static int __init can_reserve_bootmem_core(bootmem_data_t *bdata,
-			unsigned long addr, unsigned long size, int flags)
+unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn,
+				unsigned long startpfn, unsigned long endpfn)
 {
-	unsigned long sidx, eidx;
-	unsigned long i;
+	return init_bootmem_core(pgdat->bdata, freepfn, startpfn, endpfn);
+}
 
-	BUG_ON(!size);
+/**
+ * init_bootmem - register boot memory
+ * @start: pfn where the bitmap is to be placed
+ * @pages: number of available physical pages
+ *
+ * Returns the number of bytes needed to hold the bitmap.
+ */
+unsigned long __init init_bootmem(unsigned long start, unsigned long pages)
+{
+	max_low_pfn = pages;
+	min_low_pfn = start;
+	return init_bootmem_core(NODE_DATA(0)->bdata, start, 0, pages);
+}
 
-	/* out of range, don't hold other */
-	if (addr + size < bdata->node_boot_start ||
-		PFN_DOWN(addr) > bdata->node_low_pfn)
+static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
+{
+	int aligned;
+	struct page *page;
+	unsigned long start, end, pages, count = 0;
+
+	if (!bdata->node_bootmem_map)
 		return 0;
 
+	start = bdata->node_min_pfn;
+	end = bdata->node_low_pfn;
+
 	/*
-	 * Round up to index to the range.
+	 * If the start is aligned to the machines wordsize, we might
+	 * be able to free pages in bulks of that order.
 	 */
-	if (addr > bdata->node_boot_start)
-		sidx= PFN_DOWN(addr - bdata->node_boot_start);
-	else
-		sidx = 0;
+	aligned = !(start & (BITS_PER_LONG - 1));
 
-	eidx = PFN_UP(addr + size - bdata->node_boot_start);
-	if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
-		eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
+	bdebug("nid=%td start=%lx end=%lx aligned=%d\n",
+		bdata - bootmem_node_data, start, end, aligned);
 
-	for (i = sidx; i < eidx; i++) {
-		if (test_bit(i, bdata->node_bootmem_map)) {
-			if (flags & BOOTMEM_EXCLUSIVE)
-				return -EBUSY;
-		}
-	}
+	while (start < end) {
+		unsigned long *map, idx, vec;
 
-	return 0;
+		map = bdata->node_bootmem_map;
+		idx = start - bdata->node_min_pfn;
+		vec = ~map[idx / BITS_PER_LONG];
 
-}
+		if (aligned && vec == ~0UL && start + BITS_PER_LONG < end) {
+			int order = ilog2(BITS_PER_LONG);
 
-static void __init reserve_bootmem_core(bootmem_data_t *bdata,
-			unsigned long addr, unsigned long size, int flags)
-{
-	unsigned long sidx, eidx;
-	unsigned long i;
-
-	BUG_ON(!size);
+			__free_pages_bootmem(pfn_to_page(start), order);
+			count += BITS_PER_LONG;
+		} else {
+			unsigned long off = 0;
 
-	/* out of range */
-	if (addr + size < bdata->node_boot_start ||
-		PFN_DOWN(addr) > bdata->node_low_pfn)
-		return;
+			while (vec && off < BITS_PER_LONG) {
+				if (vec & 1) {
+					page = pfn_to_page(start + off);
+					__free_pages_bootmem(page, 0);
+					count++;
+				}
+				vec >>= 1;
+				off++;
+			}
+		}
+		start += BITS_PER_LONG;
+	}
 
-	/*
-	 * Round up to index to the range.
-	 */
-	if (addr > bdata->node_boot_start)
-		sidx= PFN_DOWN(addr - bdata->node_boot_start);
-	else
-		sidx = 0;
+	page = virt_to_page(bdata->node_bootmem_map);
+	pages = bdata->node_low_pfn - bdata->node_min_pfn;
+	pages = bootmem_bootmap_pages(pages);
+	count += pages;
+	while (pages--)
+		__free_pages_bootmem(page++, 0);
 
-	eidx = PFN_UP(addr + size - bdata->node_boot_start);
-	if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
-		eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
+	bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count);
 
-	for (i = sidx; i < eidx; i++) {
-		if (test_and_set_bit(i, bdata->node_bootmem_map)) {
-#ifdef CONFIG_DEBUG_BOOTMEM
-			printk("hm, page %08lx reserved twice.\n", i*PAGE_SIZE);
-#endif
-		}
-	}
+	return count;
 }
 
-static void __init free_bootmem_core(bootmem_data_t *bdata, unsigned long addr,
-				     unsigned long size)
+/**
+ * free_all_bootmem_node - release a node's free pages to the buddy allocator
+ * @pgdat: node to be released
+ *
+ * Returns the number of pages actually released.
+ */
+unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
 {
-	unsigned long sidx, eidx;
-	unsigned long i;
-
-	BUG_ON(!size);
+	register_page_bootmem_info_node(pgdat);
+	return free_all_bootmem_core(pgdat->bdata);
+}
 
-	/* out range */
-	if (addr + size < bdata->node_boot_start ||
-		PFN_DOWN(addr) > bdata->node_low_pfn)
-		return;
-	/*
-	 * round down end of usable mem, partially free pages are
-	 * considered reserved.
-	 */
+/**
+ * free_all_bootmem - release free pages to the buddy allocator
+ *
+ * Returns the number of pages actually released.
+ */
+unsigned long __init free_all_bootmem(void)
+{
+	return free_all_bootmem_core(NODE_DATA(0)->bdata);
+}
 
-	if (addr >= bdata->node_boot_start && addr < bdata->last_success)
-		bdata->last_success = addr;
+static void __init __free(bootmem_data_t *bdata,
+			unsigned long sidx, unsigned long eidx)
+{
+	unsigned long idx;
 
-	/*
-	 * Round up to index to the range.
-	 */
-	if (PFN_UP(addr) > PFN_DOWN(bdata->node_boot_start))
-		sidx = PFN_UP(addr) - PFN_DOWN(bdata->node_boot_start);
-	else
-		sidx = 0;
+	bdebug("nid=%td start=%lx end=%lx\n", bdata - bootmem_node_data,
+		sidx + bdata->node_min_pfn,
+		eidx + bdata->node_min_pfn);
 
-	eidx = PFN_DOWN(addr + size - bdata->node_boot_start);
-	if (eidx > bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start))
-		eidx = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);
+	if (bdata->hint_idx > sidx)
+		bdata->hint_idx = sidx;
 
-	for (i = sidx; i < eidx; i++) {
-		if (unlikely(!test_and_clear_bit(i, bdata->node_bootmem_map)))
+	for (idx = sidx; idx < eidx; idx++)
+		if (!test_and_clear_bit(idx, bdata->node_bootmem_map))
 			BUG();
-	}
 }
 
-/*
- * We 'merge' subsequent allocations to save space. We might 'lose'
- * some fraction of a page if allocations cannot be satisfied due to
- * size constraints on boxes where there is physical RAM space
- * fragmentation - in these cases (mostly large memory boxes) this
- * is not a problem.
- *
- * On low memory boxes we get it right in 100% of the cases.
- *
- * alignment has to be a power of 2 value.
- *
- * NOTE:  This function is _not_ reentrant.
- */
-void * __init
-__alloc_bootmem_core(struct bootmem_data *bdata, unsigned long size,
-	      unsigned long align, unsigned long goal, unsigned long limit)
+static int __init __reserve(bootmem_data_t *bdata, unsigned long sidx,
+			unsigned long eidx, int flags)
 {
-	unsigned long areasize, preferred;
-	unsigned long i, start = 0, incr, eidx, end_pfn;
-	void *ret;
-	unsigned long node_boot_start;
-	void *node_bootmem_map;
-
-	if (!size) {
-		printk("__alloc_bootmem_core(): zero-sized request\n");
-		BUG();
-	}
-	BUG_ON(align & (align-1));
-
-	/* on nodes without memory - bootmem_map is NULL */
-	if (!bdata->node_bootmem_map)
-		return NULL;
+	unsigned long idx;
+	int exclusive = flags & BOOTMEM_EXCLUSIVE;
+
+	bdebug("nid=%td start=%lx end=%lx flags=%x\n",
+		bdata - bootmem_node_data,
+		sidx + bdata->node_min_pfn,
+		eidx + bdata->node_min_pfn,
+		flags);
+
+	for (idx = sidx; idx < eidx; idx++)
+		if (test_and_set_bit(idx, bdata->node_bootmem_map)) {
+			if (exclusive) {
+				__free(bdata, sidx, idx);
+				return -EBUSY;
+			}
+			bdebug("silent double reserve of PFN %lx\n",
+				idx + bdata->node_min_pfn);
+		}
+	return 0;
+}
 
-	/* bdata->node_boot_start is supposed to be (12+6)bits alignment on x86_64 ? */
-	node_boot_start = bdata->node_boot_start;
-	node_bootmem_map = bdata->node_bootmem_map;
-	if (align) {
-		node_boot_start = ALIGN(bdata->node_boot_start, align);
-		if (node_boot_start > bdata->node_boot_start)
-			node_bootmem_map = (unsigned long *)bdata->node_bootmem_map +
-			    PFN_DOWN(node_boot_start - bdata->node_boot_start)/BITS_PER_LONG;
-	}
+static int __init mark_bootmem_node(bootmem_data_t *bdata,
+				unsigned long start, unsigned long end,
+				int reserve, int flags)
+{
+	unsigned long sidx, eidx;
 
-	if (limit && node_boot_start >= limit)
-		return NULL;
+	bdebug("nid=%td start=%lx end=%lx reserve=%d flags=%x\n",
+		bdata - bootmem_node_data, start, end, reserve, flags);
 
-	end_pfn = bdata->node_low_pfn;
-	limit = PFN_DOWN(limit);
-	if (limit && end_pfn > limit)
-		end_pfn = limit;
+	BUG_ON(start < bdata->node_min_pfn);
+	BUG_ON(end > bdata->node_low_pfn);
 
-	eidx = end_pfn - PFN_DOWN(node_boot_start);
+	sidx = start - bdata->node_min_pfn;
+	eidx = end - bdata->node_min_pfn;
 
-	/*
-	 * We try to allocate bootmem pages above 'goal'
-	 * first, then we try to allocate lower pages.
-	 */
-	preferred = 0;
-	if (goal && PFN_DOWN(goal) < end_pfn) {
-		if (goal > node_boot_start)
-			preferred = goal - node_boot_start;
-
-		if (bdata->last_success > node_boot_start &&
-			bdata->last_success - node_boot_start >= preferred)
-			if (!limit || (limit && limit > bdata->last_success))
-				preferred = bdata->last_success - node_boot_start;
-	}
+	if (reserve)
+		return __reserve(bdata, sidx, eidx, flags);
+	else
+		__free(bdata, sidx, eidx);
+	return 0;
+}
 
-	preferred = PFN_DOWN(ALIGN(preferred, align));
-	areasize = (size + PAGE_SIZE-1) / PAGE_SIZE;
-	incr = align >> PAGE_SHIFT ? : 1;
+static int __init mark_bootmem(unsigned long start, unsigned long end,
+				int reserve, int flags)
+{
+	unsigned long pos;
+	bootmem_data_t *bdata;
 
-restart_scan:
-	for (i = preferred; i < eidx;) {
-		unsigned long j;
+	pos = start;
+	list_for_each_entry(bdata, &bdata_list, list) {
+		int err;
+		unsigned long max;
 
-		i = find_next_zero_bit(node_bootmem_map, eidx, i);
-		i = ALIGN(i, incr);
-		if (i >= eidx)
-			break;
-		if (test_bit(i, node_bootmem_map)) {
-			i += incr;
+		if (pos < bdata->node_min_pfn ||
+		    pos >= bdata->node_low_pfn) {
+			BUG_ON(pos != start);
 			continue;
 		}
-		for (j = i + 1; j < i + areasize; ++j) {
-			if (j >= eidx)
-				goto fail_block;
-			if (test_bit(j, node_bootmem_map))
-				goto fail_block;
-		}
-		start = i;
-		goto found;
-	fail_block:
-		i = ALIGN(j, incr);
-		if (i == j)
-			i += incr;
-	}
 
-	if (preferred > 0) {
-		preferred = 0;
-		goto restart_scan;
-	}
-	return NULL;
+		max = min(bdata->node_low_pfn, end);
 
-found:
-	bdata->last_success = PFN_PHYS(start) + node_boot_start;
-	BUG_ON(start >= eidx);
-
-	/*
-	 * Is the next page of the previous allocation-end the start
-	 * of this allocation's buffer? If yes then we can 'merge'
-	 * the previous partial page with this allocation.
-	 */
-	if (align < PAGE_SIZE &&
-	    bdata->last_offset && bdata->last_pos+1 == start) {
-		unsigned long offset, remaining_size;
-		offset = ALIGN(bdata->last_offset, align);
-		BUG_ON(offset > PAGE_SIZE);
-		remaining_size = PAGE_SIZE - offset;
-		if (size < remaining_size) {
-			areasize = 0;
-			/* last_pos unchanged */
-			bdata->last_offset = offset + size;
-			ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
-					   offset + node_boot_start);
-		} else {
-			remaining_size = size - remaining_size;
-			areasize = (remaining_size + PAGE_SIZE-1) / PAGE_SIZE;
-			ret = phys_to_virt(bdata->last_pos * PAGE_SIZE +
-					   offset + node_boot_start);
-			bdata->last_pos = start + areasize - 1;
-			bdata->last_offset = remaining_size;
+		err = mark_bootmem_node(bdata, pos, max, reserve, flags);
+		if (reserve && err) {
+			mark_bootmem(start, pos, 0, 0);
+			return err;
 		}
-		bdata->last_offset &= ~PAGE_MASK;
-	} else {
-		bdata->last_pos = start + areasize - 1;
-		bdata->last_offset = size & ~PAGE_MASK;
-		ret = phys_to_virt(start * PAGE_SIZE + node_boot_start);
-	}
 
-	/*
-	 * Reserve the area now:
-	 */
-	for (i = start; i < start + areasize; i++)
-		if (unlikely(test_and_set_bit(i, node_bootmem_map)))
-			BUG();
-	memset(ret, 0, size);
-	return ret;
+		if (max == end)
+			return 0;
+		pos = bdata->node_low_pfn;
+	}
+	BUG();
 }
 
-static unsigned long __init free_all_bootmem_core(pg_data_t *pgdat)
+/**
+ * free_bootmem_node - mark a page range as usable
+ * @pgdat: node the range resides on
+ * @physaddr: starting address of the range
+ * @size: size of the range in bytes
+ *
+ * Partial pages will be considered reserved and left as they are.
+ *
+ * The range must reside completely on the specified node.
+ */
+void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
+			      unsigned long size)
 {
-	struct page *page;
-	unsigned long pfn;
-	bootmem_data_t *bdata = pgdat->bdata;
-	unsigned long i, count, total = 0;
-	unsigned long idx;
-	unsigned long *map; 
-	int gofast = 0;
-
-	BUG_ON(!bdata->node_bootmem_map);
-
-	count = 0;
-	/* first extant page of the node */
-	pfn = PFN_DOWN(bdata->node_boot_start);
-	idx = bdata->node_low_pfn - pfn;
-	map = bdata->node_bootmem_map;
-	/* Check physaddr is O(LOG2(BITS_PER_LONG)) page aligned */
-	if (bdata->node_boot_start == 0 ||
-	    ffs(bdata->node_boot_start) - PAGE_SHIFT > ffs(BITS_PER_LONG))
-		gofast = 1;
-	for (i = 0; i < idx; ) {
-		unsigned long v = ~map[i / BITS_PER_LONG];
-
-		if (gofast && v == ~0UL) {
-			int order;
-
-			page = pfn_to_page(pfn);
-			count += BITS_PER_LONG;
-			order = ffs(BITS_PER_LONG) - 1;
-			__free_pages_bootmem(page, order);
-			i += BITS_PER_LONG;
-			page += BITS_PER_LONG;
-		} else if (v) {
-			unsigned long m;
-
-			page = pfn_to_page(pfn);
-			for (m = 1; m && i < idx; m<<=1, page++, i++) {
-				if (v & m) {
-					count++;
-					__free_pages_bootmem(page, 0);
-				}
-			}
-		} else {
-			i += BITS_PER_LONG;
-		}
-		pfn += BITS_PER_LONG;
-	}
-	total += count;
+	unsigned long start, end;
 
-	/*
-	 * Now free the allocator bitmap itself, it's not
-	 * needed anymore:
-	 */
-	page = virt_to_page(bdata->node_bootmem_map);
-	count = 0;
-	idx = (get_mapsize(bdata) + PAGE_SIZE-1) >> PAGE_SHIFT;
-	for (i = 0; i < idx; i++, page++) {
-		__free_pages_bootmem(page, 0);
-		count++;
-	}
-	total += count;
-	bdata->node_bootmem_map = NULL;
+	start = PFN_UP(physaddr);
+	end = PFN_DOWN(physaddr + size);
 
-	return total;
+	mark_bootmem_node(pgdat->bdata, start, end, 0, 0);
 }
 
-unsigned long __init init_bootmem_node(pg_data_t *pgdat, unsigned long freepfn,
-				unsigned long startpfn, unsigned long endpfn)
-{
-	return init_bootmem_core(pgdat, freepfn, startpfn, endpfn);
-}
-
-int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
-				 unsigned long size, int flags)
+/**
+ * free_bootmem - mark a page range as usable
+ * @addr: starting address of the range
+ * @size: size of the range in bytes
+ *
+ * Partial pages will be considered reserved and left as they are.
+ *
+ * The range must be contiguous but may span node boundaries.
+ */
+void __init free_bootmem(unsigned long addr, unsigned long size)
 {
-	int ret;
+	unsigned long start, end;
 
-	ret = can_reserve_bootmem_core(pgdat->bdata, physaddr, size, flags);
-	if (ret < 0)
-		return -ENOMEM;
-	reserve_bootmem_core(pgdat->bdata, physaddr, size, flags);
+	start = PFN_UP(addr);
+	end = PFN_DOWN(addr + size);
 
-	return 0;
+	mark_bootmem(start, end, 0, 0);
 }
 
-void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
-			      unsigned long size)
+/**
+ * reserve_bootmem_node - mark a page range as reserved
+ * @pgdat: node the range resides on
+ * @physaddr: starting address of the range
+ * @size: size of the range in bytes
+ * @flags: reservation flags (see linux/bootmem.h)
+ *
+ * Partial pages will be reserved.
+ *
+ * The range must reside completely on the specified node.
+ */
+int __init reserve_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
+				 unsigned long size, int flags)
 {
-	free_bootmem_core(pgdat->bdata, physaddr, size);
-}
+	unsigned long start, end;
 
-unsigned long __init free_all_bootmem_node(pg_data_t *pgdat)
-{
-	register_page_bootmem_info_node(pgdat);
-	return free_all_bootmem_core(pgdat);
-}
+	start = PFN_DOWN(physaddr);
+	end = PFN_UP(physaddr + size);
 
-unsigned long __init init_bootmem(unsigned long start, unsigned long pages)
-{
-	max_low_pfn = pages;
-	min_low_pfn = start;
-	return init_bootmem_core(NODE_DATA(0), start, 0, pages);
+	return mark_bootmem_node(pgdat->bdata, start, end, 1, flags);
 }
 
 #ifndef CONFIG_HAVE_ARCH_BOOTMEM_NODE
+/**
+ * reserve_bootmem - mark a page range as usable
+ * @addr: starting address of the range
+ * @size: size of the range in bytes
+ * @flags: reservation flags (see linux/bootmem.h)
+ *
+ * Partial pages will be reserved.
+ *
+ * The range must be contiguous but may span node boundaries.
+ */
 int __init reserve_bootmem(unsigned long addr, unsigned long size,
 			    int flags)
 {
-	bootmem_data_t *bdata;
-	int ret;
+	unsigned long start, end;
 
-	list_for_each_entry(bdata, &bdata_list, list) {
-		ret = can_reserve_bootmem_core(bdata, addr, size, flags);
-		if (ret < 0)
-			return ret;
-	}
-	list_for_each_entry(bdata, &bdata_list, list)
-		reserve_bootmem_core(bdata, addr, size, flags);
+	start = PFN_DOWN(addr);
+	end = PFN_UP(addr + size);
 
-	return 0;
+	return mark_bootmem(start, end, 1, flags);
 }
 #endif /* !CONFIG_HAVE_ARCH_BOOTMEM_NODE */
 
-void __init free_bootmem(unsigned long addr, unsigned long size)
+static void * __init alloc_bootmem_core(struct bootmem_data *bdata,
+				unsigned long size, unsigned long align,
+				unsigned long goal, unsigned long limit)
 {
-	bootmem_data_t *bdata;
-	list_for_each_entry(bdata, &bdata_list, list)
-		free_bootmem_core(bdata, addr, size);
-}
+	unsigned long fallback = 0;
+	unsigned long min, max, start, sidx, midx, step;
 
-unsigned long __init free_all_bootmem(void)
-{
-	return free_all_bootmem_core(NODE_DATA(0));
+	BUG_ON(!size);
+	BUG_ON(align & (align - 1));
+	BUG_ON(limit && goal + size > limit);
+
+	if (!bdata->node_bootmem_map)
+		return NULL;
+
+	bdebug("nid=%td size=%lx [%lu pages] align=%lx goal=%lx limit=%lx\n",
+		bdata - bootmem_node_data, size, PAGE_ALIGN(size) >> PAGE_SHIFT,
+		align, goal, limit);
+
+	min = bdata->node_min_pfn;
+	max = bdata->node_low_pfn;
+
+	goal >>= PAGE_SHIFT;
+	limit >>= PAGE_SHIFT;
+
+	if (limit && max > limit)
+		max = limit;
+	if (max <= min)
+		return NULL;
+
+	step = max(align >> PAGE_SHIFT, 1UL);
+
+	if (goal && min < goal && goal < max)
+		start = ALIGN(goal, step);
+	else
+		start = ALIGN(min, step);
+
+	sidx = start - bdata->node_min_pfn;;
+	midx = max - bdata->node_min_pfn;
+
+	if (bdata->hint_idx > sidx) {
+		/*
+		 * Handle the valid case of sidx being zero and still
+		 * catch the fallback below.
+		 */
+		fallback = sidx + 1;
+		sidx = ALIGN(bdata->hint_idx, step);
+	}
+
+	while (1) {
+		int merge;
+		void *region;
+		unsigned long eidx, i, start_off, end_off;
+find_block:
+		sidx = find_next_zero_bit(bdata->node_bootmem_map, midx, sidx);
+		sidx = ALIGN(sidx, step);
+		eidx = sidx + PFN_UP(size);
+
+		if (sidx >= midx || eidx > midx)
+			break;
+
+		for (i = sidx; i < eidx; i++)
+			if (test_bit(i, bdata->node_bootmem_map)) {
+				sidx = ALIGN(i, step);
+				if (sidx == i)
+					sidx += step;
+				goto find_block;
+			}
+
+		if (bdata->last_end_off &&
+				PFN_DOWN(bdata->last_end_off) + 1 == sidx)
+			start_off = ALIGN(bdata->last_end_off, align);
+		else
+			start_off = PFN_PHYS(sidx);
+
+		merge = PFN_DOWN(start_off) < sidx;
+		end_off = start_off + size;
+
+		bdata->last_end_off = end_off;
+		bdata->hint_idx = PFN_UP(end_off);
+
+		/*
+		 * Reserve the area now:
+		 */
+		if (__reserve(bdata, PFN_DOWN(start_off) + merge,
+				PFN_UP(end_off), BOOTMEM_EXCLUSIVE))
+			BUG();
+
+		region = phys_to_virt(PFN_PHYS(bdata->node_min_pfn) +
+				start_off);
+		memset(region, 0, size);
+		return region;
+	}
+
+	if (fallback) {
+		sidx = ALIGN(fallback - 1, step);
+		fallback = 0;
+		goto find_block;
+	}
+
+	return NULL;
 }
 
-void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
-				      unsigned long goal)
+static void * __init ___alloc_bootmem_nopanic(unsigned long size,
+					unsigned long align,
+					unsigned long goal,
+					unsigned long limit)
 {
 	bootmem_data_t *bdata;
-	void *ptr;
 
+restart:
 	list_for_each_entry(bdata, &bdata_list, list) {
-		ptr = __alloc_bootmem_core(bdata, size, align, goal, 0);
-		if (ptr)
-			return ptr;
+		void *region;
+
+		if (goal && bdata->node_low_pfn <= PFN_DOWN(goal))
+			continue;
+		if (limit && bdata->node_min_pfn >= PFN_DOWN(limit))
+			break;
+
+		region = alloc_bootmem_core(bdata, size, align, goal, limit);
+		if (region)
+			return region;
+	}
+
+	if (goal) {
+		goal = 0;
+		goto restart;
 	}
+
 	return NULL;
 }
 
-void * __init __alloc_bootmem(unsigned long size, unsigned long align,
-			      unsigned long goal)
+/**
+ * __alloc_bootmem_nopanic - allocate boot memory without panicking
+ * @size: size of the request in bytes
+ * @align: alignment of the region
+ * @goal: preferred starting address of the region
+ *
+ * The goal is dropped if it can not be satisfied and the allocation will
+ * fall back to memory below @goal.
+ *
+ * Allocation may happen on any node in the system.
+ *
+ * Returns NULL on failure.
+ */
+void * __init __alloc_bootmem_nopanic(unsigned long size, unsigned long align,
+					unsigned long goal)
 {
-	void *mem = __alloc_bootmem_nopanic(size,align,goal);
+	return ___alloc_bootmem_nopanic(size, align, goal, 0);
+}
+
+static void * __init ___alloc_bootmem(unsigned long size, unsigned long align,
+					unsigned long goal, unsigned long limit)
+{
+	void *mem = ___alloc_bootmem_nopanic(size, align, goal, limit);
 
 	if (mem)
 		return mem;
@@ -534,78 +570,135 @@ void * __init __alloc_bootmem(unsigned long size, unsigned long align,
 	return NULL;
 }
 
+/**
+ * __alloc_bootmem - allocate boot memory
+ * @size: size of the request in bytes
+ * @align: alignment of the region
+ * @goal: preferred starting address of the region
+ *
+ * The goal is dropped if it can not be satisfied and the allocation will
+ * fall back to memory below @goal.
+ *
+ * Allocation may happen on any node in the system.
+ *
+ * The function panics if the request can not be satisfied.
+ */
+void * __init __alloc_bootmem(unsigned long size, unsigned long align,
+			      unsigned long goal)
+{
+	return ___alloc_bootmem(size, align, goal, 0);
+}
 
-void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
-				   unsigned long align, unsigned long goal)
+static void * __init ___alloc_bootmem_node(bootmem_data_t *bdata,
+				unsigned long size, unsigned long align,
+				unsigned long goal, unsigned long limit)
 {
 	void *ptr;
 
-	ptr = __alloc_bootmem_core(pgdat->bdata, size, align, goal, 0);
+	ptr = alloc_bootmem_core(bdata, size, align, goal, limit);
 	if (ptr)
 		return ptr;
 
-	return __alloc_bootmem(size, align, goal);
+	return ___alloc_bootmem(size, align, goal, limit);
+}
+
+/**
+ * __alloc_bootmem_node - allocate boot memory from a specific node
+ * @pgdat: node to allocate from
+ * @size: size of the request in bytes
+ * @align: alignment of the region
+ * @goal: preferred starting address of the region
+ *
+ * The goal is dropped if it can not be satisfied and the allocation will
+ * fall back to memory below @goal.
+ *
+ * Allocation may fall back to any node in the system if the specified node
+ * can not hold the requested memory.
+ *
+ * The function panics if the request can not be satisfied.
+ */
+void * __init __alloc_bootmem_node(pg_data_t *pgdat, unsigned long size,
+				   unsigned long align, unsigned long goal)
+{
+	return ___alloc_bootmem_node(pgdat->bdata, size, align, goal, 0);
 }
 
 #ifdef CONFIG_SPARSEMEM
+/**
+ * alloc_bootmem_section - allocate boot memory from a specific section
+ * @size: size of the request in bytes
+ * @section_nr: sparse map section to allocate from
+ *
+ * Return NULL on failure.
+ */
 void * __init alloc_bootmem_section(unsigned long size,
 				    unsigned long section_nr)
 {
-	void *ptr;
-	unsigned long limit, goal, start_nr, end_nr, pfn;
-	struct pglist_data *pgdat;
+	bootmem_data_t *bdata;
+	unsigned long pfn, goal, limit;
 
 	pfn = section_nr_to_pfn(section_nr);
-	goal = PFN_PHYS(pfn);
-	limit = PFN_PHYS(section_nr_to_pfn(section_nr + 1)) - 1;
-	pgdat = NODE_DATA(early_pfn_to_nid(pfn));
-	ptr = __alloc_bootmem_core(pgdat->bdata, size, SMP_CACHE_BYTES, goal,
-				   limit);
+	goal = pfn << PAGE_SHIFT;
+	limit = section_nr_to_pfn(section_nr + 1) << PAGE_SHIFT;
+	bdata = &bootmem_node_data[early_pfn_to_nid(pfn)];
 
-	if (!ptr)
-		return NULL;
+	return alloc_bootmem_core(bdata, size, SMP_CACHE_BYTES, goal, limit);
+}
+#endif
 
-	start_nr = pfn_to_section_nr(PFN_DOWN(__pa(ptr)));
-	end_nr = pfn_to_section_nr(PFN_DOWN(__pa(ptr) + size));
-	if (start_nr != section_nr || end_nr != section_nr) {
-		printk(KERN_WARNING "alloc_bootmem failed on section %ld.\n",
-		       section_nr);
-		free_bootmem_core(pgdat->bdata, __pa(ptr), size);
-		ptr = NULL;
-	}
+void * __init __alloc_bootmem_node_nopanic(pg_data_t *pgdat, unsigned long size,
+				   unsigned long align, unsigned long goal)
+{
+	void *ptr;
 
-	return ptr;
+	ptr = alloc_bootmem_core(pgdat->bdata, size, align, goal, 0);
+	if (ptr)
+		return ptr;
+
+	return __alloc_bootmem_nopanic(size, align, goal);
 }
-#endif
 
 #ifndef ARCH_LOW_ADDRESS_LIMIT
 #define ARCH_LOW_ADDRESS_LIMIT	0xffffffffUL
 #endif
 
+/**
+ * __alloc_bootmem_low - allocate low boot memory
+ * @size: size of the request in bytes
+ * @align: alignment of the region
+ * @goal: preferred starting address of the region
+ *
+ * The goal is dropped if it can not be satisfied and the allocation will
+ * fall back to memory below @goal.
+ *
+ * Allocation may happen on any node in the system.
+ *
+ * The function panics if the request can not be satisfied.
+ */
 void * __init __alloc_bootmem_low(unsigned long size, unsigned long align,
 				  unsigned long goal)
 {
-	bootmem_data_t *bdata;
-	void *ptr;
-
-	list_for_each_entry(bdata, &bdata_list, list) {
-		ptr = __alloc_bootmem_core(bdata, size, align, goal,
-						ARCH_LOW_ADDRESS_LIMIT);
-		if (ptr)
-			return ptr;
-	}
-
-	/*
-	 * Whoops, we cannot satisfy the allocation request.
-	 */
-	printk(KERN_ALERT "low bootmem alloc of %lu bytes failed!\n", size);
-	panic("Out of low memory");
-	return NULL;
+	return ___alloc_bootmem(size, align, goal, ARCH_LOW_ADDRESS_LIMIT);
 }
 
+/**
+ * __alloc_bootmem_low_node - allocate low boot memory from a specific node
+ * @pgdat: node to allocate from
+ * @size: size of the request in bytes
+ * @align: alignment of the region
+ * @goal: preferred starting address of the region
+ *
+ * The goal is dropped if it can not be satisfied and the allocation will
+ * fall back to memory below @goal.
+ *
+ * Allocation may fall back to any node in the system if the specified node
+ * can not hold the requested memory.
+ *
+ * The function panics if the request can not be satisfied.
+ */
 void * __init __alloc_bootmem_low_node(pg_data_t *pgdat, unsigned long size,
 				       unsigned long align, unsigned long goal)
 {
-	return __alloc_bootmem_core(pgdat->bdata, size, align, goal,
-				    ARCH_LOW_ADDRESS_LIMIT);
+	return ___alloc_bootmem_node(pgdat->bdata, size, align,
+				goal, ARCH_LOW_ADDRESS_LIMIT);
 }