1 files changed, 50 insertions, 5 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 34a4c12d2675..facc25ee6e2d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1747,16 +1747,38 @@ void __init page_alloc_init_late(void)
 }
 
 #ifdef CONFIG_CMA
+static void __init adjust_present_page_count(struct page *page, long count)
+{
+	struct zone *zone = page_zone(page);
+
+	/* We don't need to hold a lock since it is boot-up process */
+	zone->present_pages += count;
+}
+
 /* Free whole pageblock and set its migration type to MIGRATE_CMA. */
 void __init init_cma_reserved_pageblock(struct page *page)
 {
 	unsigned i = pageblock_nr_pages;
+	unsigned long pfn = page_to_pfn(page);
 	struct page *p = page;
+	int nid = page_to_nid(page);
+
+	/*
+	 * ZONE_MOVABLE will steal present pages from other zones by
+	 * changing page links so page_zone() is changed. Before that,
+	 * we need to adjust previous zone's page count first.
+	 */
+	adjust_present_page_count(page, -pageblock_nr_pages);
 
 	do {
 		__ClearPageReserved(p);
 		set_page_count(p, 0);
-	} while (++p, --i);
+
+		/* Steal pages from other zones */
+		set_page_links(p, ZONE_MOVABLE, nid, pfn);
+	} while (++p, ++pfn, --i);
+
+	adjust_present_page_count(page, pageblock_nr_pages);
 
 	set_pageblock_migratetype(page, MIGRATE_CMA);
 
@@ -6208,6 +6230,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat)
 {
 	enum zone_type j;
 	int nid = pgdat->node_id;
+	unsigned long node_end_pfn = 0;
 
 	pgdat_resize_init(pgdat);
 #ifdef CONFIG_NUMA_BALANCING
@@ -6235,9 +6258,13 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat)
 		struct zone *zone = pgdat->node_zones + j;
 		unsigned long size, realsize, freesize, memmap_pages;
 		unsigned long zone_start_pfn = zone->zone_start_pfn;
+		unsigned long movable_size = 0;
 
 		size = zone->spanned_pages;
 		realsize = freesize = zone->present_pages;
+		if (zone_end_pfn(zone) > node_end_pfn)
+			node_end_pfn = zone_end_pfn(zone);
+
 
 		/*
 		 * Adjust freesize so that it accounts for how much memory
@@ -6286,12 +6313,30 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat)
 		zone_seqlock_init(zone);
 		zone_pcp_init(zone);
 
-		if (!size)
+		/*
+		 * The size of the CMA area is unknown now so we need to
+		 * prepare the memory for the usemap at maximum.
+		 */
+		if (IS_ENABLED(CONFIG_CMA) && j == ZONE_MOVABLE &&
+			pgdat->node_spanned_pages) {
+			movable_size = node_end_pfn - pgdat->node_start_pfn;
+		}
+
+		if (!size && !movable_size)
 			continue;
 
 		set_pageblock_order();
-		setup_usemap(pgdat, zone, zone_start_pfn, size);
-		init_currently_empty_zone(zone, zone_start_pfn, size);
+		if (movable_size) {
+			zone->zone_start_pfn = pgdat->node_start_pfn;
+			zone->spanned_pages = movable_size;
+			setup_usemap(pgdat, zone,
+				pgdat->node_start_pfn, movable_size);
+			init_currently_empty_zone(zone,
+				pgdat->node_start_pfn, movable_size);
+		} else {
+			setup_usemap(pgdat, zone, zone_start_pfn, size);
+			init_currently_empty_zone(zone, zone_start_pfn, size);
+		}
 		memmap_init(size, nid, j, zone_start_pfn);
 	}
 }
@@ -7932,7 +7977,7 @@ void free_contig_range(unsigned long pfn, unsigned nr_pages)
 }
 #endif
 
-#ifdef CONFIG_MEMORY_HOTPLUG
+#if defined CONFIG_MEMORY_HOTPLUG || defined CONFIG_CMA
 /*
  * The zone indicated has a new number of managed_pages; batch sizes and percpu
  * page high values need to be recalulated.