+/**
+ * __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
+ * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @p_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;
+}
+
+#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;
+ phys_addr_t end = base + size;
+ int i;
+
+ /* we'll create at most two more regions */
+ while (type->cnt + 2 > type->max)
+ if (memblock_double_array(type) < 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 = rend - rgn->base;
+ memblock_insert_region(type, i, rbase, base - rbase,
+ rgn->nid);
+ } else if (rend > end) {
+ /*
+ * @rgn intersects from above. Split and redo the
+ * current region - the new bottom half.
+ */
+ rgn->base = end;
+ rgn->size = rend - rgn->base;
+ memblock_insert_region(type, i--, rbase, end - rbase,
+ rgn->nid);
+ } else {
+ /* @rgn is fully contained, set ->nid */
+ rgn->nid = nid;
+ }
+ }
+
+ memblock_merge_regions(type);
+ return 0;
+}
+#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
+