Merge branch 'akpm' (patches from Andrew)

Merge second patch-bomb from Andrew Morton:
 "Almost all of the rest of MM.  There was an unusually large amount of
  MM material this time"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (141 commits)
  zpool: remove no-op module init/exit
  mm: zbud: constify the zbud_ops
  mm: zpool: constify the zpool_ops
  mm: swap: zswap: maybe_preload & refactoring
  zram: unify error reporting
  zsmalloc: remove null check from destroy_handle_cache()
  zsmalloc: do not take class lock in zs_shrinker_count()
  zsmalloc: use class->pages_per_zspage
  zsmalloc: consider ZS_ALMOST_FULL as migrate source
  zsmalloc: partial page ordering within a fullness_list
  zsmalloc: use shrinker to trigger auto-compaction
  zsmalloc: account the number of compacted pages
  zsmalloc/zram: introduce zs_pool_stats api
  zsmalloc: cosmetic compaction code adjustments
  zsmalloc: introduce zs_can_compact() function
  zsmalloc: always keep per-class stats
  zsmalloc: drop unused variable `nr_to_migrate'
  mm/memblock.c: fix comment in __next_mem_range()
  mm/page_alloc.c: fix type information of memoryless node
  memory-hotplug: fix comments in zone_spanned_pages_in_node() and zone_spanned_pages_in_node()
  ...

36 files changed, 1243 insertions, 1030 deletions

diff --git a/mm/bootmem.c b/mm/bootmem.c
index a23dd19..3b63807 100644
--- a/mm/bootmem.c
+++ b/mm/bootmem.c
@@ -236,6 +236,7 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)
 	count += pages;
 	while (pages--)
 		__free_pages_bootmem(page++, cur++, 0);
+	bdata->node_bootmem_map = NULL;
 
 	bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count);
 
@@ -294,6 +295,9 @@ static void __init __free(bootmem_data_t *bdata,
 		sidx + bdata->node_min_pfn,
 		eidx + bdata->node_min_pfn);
 
+	if (WARN_ON(bdata->node_bootmem_map == NULL))
+		return;
+
 	if (bdata->hint_idx > sidx)
 		bdata->hint_idx = sidx;
 
@@ -314,6 +318,9 @@ static int __init __reserve(bootmem_data_t *bdata, unsigned long sidx,
 		eidx + bdata->node_min_pfn,
 		flags);
 
+	if (WARN_ON(bdata->node_bootmem_map == NULL))
+		return 0;
+
 	for (idx = sidx; idx < eidx; idx++)
 		if (test_and_set_bit(idx, bdata->node_bootmem_map)) {
 			if (exclusive) {
diff --git a/mm/compaction.c b/mm/compaction.c
index 018f08d..c5c627a 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -207,6 +207,13 @@ static inline bool isolation_suitable(struct compact_control *cc,
 	return !get_pageblock_skip(page);
 }
 
+static void reset_cached_positions(struct zone *zone)
+{
+	zone->compact_cached_migrate_pfn[0] = zone->zone_start_pfn;
+	zone->compact_cached_migrate_pfn[1] = zone->zone_start_pfn;
+	zone->compact_cached_free_pfn = zone_end_pfn(zone);
+}
+
 /*
  * This function is called to clear all cached information on pageblocks that
  * should be skipped for page isolation when the migrate and free page scanner
@@ -218,9 +225,6 @@ static void __reset_isolation_suitable(struct zone *zone)
 	unsigned long end_pfn = zone_end_pfn(zone);
 	unsigned long pfn;
 
-	zone->compact_cached_migrate_pfn[0] = start_pfn;
-	zone->compact_cached_migrate_pfn[1] = start_pfn;
-	zone->compact_cached_free_pfn = end_pfn;
 	zone->compact_blockskip_flush = false;
 
 	/* Walk the zone and mark every pageblock as suitable for isolation */
@@ -238,6 +242,8 @@ static void __reset_isolation_suitable(struct zone *zone)
 
 		clear_pageblock_skip(page);
 	}
+
+	reset_cached_positions(zone);
 }
 
 void reset_isolation_suitable(pg_data_t *pgdat)
@@ -431,6 +437,24 @@ static unsigned long isolate_freepages_block(struct compact_control *cc,
 
 		if (!valid_page)
 			valid_page = page;
+
+		/*
+		 * For compound pages such as THP and hugetlbfs, we can save
+		 * potentially a lot of iterations if we skip them at once.
+		 * The check is racy, but we can consider only valid values
+		 * and the only danger is skipping too much.
+		 */
+		if (PageCompound(page)) {
+			unsigned int comp_order = compound_order(page);
+
+			if (likely(comp_order < MAX_ORDER)) {
+				blockpfn += (1UL << comp_order) - 1;
+				cursor += (1UL << comp_order) - 1;
+			}
+
+			goto isolate_fail;
+		}
+
 		if (!PageBuddy(page))
 			goto isolate_fail;
 
@@ -490,6 +514,13 @@ isolate_fail:
 
 	}
 
+	/*
+	 * There is a tiny chance that we have read bogus compound_order(),
+	 * so be careful to not go outside of the pageblock.
+	 */
+	if (unlikely(blockpfn > end_pfn))
+		blockpfn = end_pfn;
+
 	trace_mm_compaction_isolate_freepages(*start_pfn, blockpfn,
 					nr_scanned, total_isolated);
 
@@ -674,6 +705,8 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
 
 	/* Time to isolate some pages for migration */
 	for (; low_pfn < end_pfn; low_pfn++) {
+		bool is_lru;
+
 		/*
 		 * Periodically drop the lock (if held) regardless of its
 		 * contention, to give chance to IRQs. Abort async compaction
@@ -717,36 +750,35 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
 		 * It's possible to migrate LRU pages and balloon pages
 		 * Skip any other type of page
 		 */
-		if (!PageLRU(page)) {
+		is_lru = PageLRU(page);
+		if (!is_lru) {
 			if (unlikely(balloon_page_movable(page))) {
 				if (balloon_page_isolate(page)) {
 					/* Successfully isolated */
 					goto isolate_success;
 				}
 			}
-			continue;
 		}
 
 		/*
-		 * PageLRU is set. lru_lock normally excludes isolation
-		 * splitting and collapsing (collapsing has already happened
-		 * if PageLRU is set) but the lock is not necessarily taken
-		 * here and it is wasteful to take it just to check transhuge.
-		 * Check TransHuge without lock and skip the whole pageblock if
-		 * it's either a transhuge or hugetlbfs page, as calling
-		 * compound_order() without preventing THP from splitting the
-		 * page underneath us may return surprising results.
+		 * Regardless of being on LRU, compound pages such as THP and
+		 * hugetlbfs are not to be compacted. We can potentially save
+		 * a lot of iterations if we skip them at once. The check is
+		 * racy, but we can consider only valid values and the only
+		 * danger is skipping too much.
 		 */
-		if (PageTransHuge(page)) {
-			if (!locked)
-				low_pfn = ALIGN(low_pfn + 1,
-						pageblock_nr_pages) - 1;
-			else
-				low_pfn += (1 << compound_order(page)) - 1;
+		if (PageCompound(page)) {
+			unsigned int comp_order = compound_order(page);
+
+			if (likely(comp_order < MAX_ORDER))
+				low_pfn += (1UL << comp_order) - 1;
 
 			continue;
 		}
 
+		if (!is_lru)
+			continue;
+
 		/*
 		 * Migration will fail if an anonymous page is pinned in memory,
 		 * so avoid taking lru_lock and isolating it unnecessarily in an
@@ -763,11 +795,17 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
 			if (!locked)
 				break;
 
-			/* Recheck PageLRU and PageTransHuge under lock */
+			/* Recheck PageLRU and PageCompound under lock */
 			if (!PageLRU(page))
 				continue;
-			if (PageTransHuge(page)) {
-				low_pfn += (1 << compound_order(page)) - 1;
+
+			/*
+			 * Page become compound since the non-locked check,
+			 * and it's on LRU. It can only be a THP so the order
+			 * is safe to read and it's 0 for tail pages.
+			 */
+			if (unlikely(PageCompound(page))) {
+				low_pfn += (1UL << compound_order(page)) - 1;
 				continue;
 			}
 		}
@@ -778,7 +816,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
 		if (__isolate_lru_page(page, isolate_mode) != 0)
 			continue;
 
-		VM_BUG_ON_PAGE(PageTransCompound(page), page);
+		VM_BUG_ON_PAGE(PageCompound(page), page);
 
 		/* Successfully isolated */
 		del_page_from_lru_list(page, lruvec, page_lru(page));
@@ -898,6 +936,16 @@ static bool suitable_migration_target(struct page *page)
 }
 
 /*
+ * Test whether the free scanner has reached the same or lower pageblock than
+ * the migration scanner, and compaction should thus terminate.
+ */
+static inline bool compact_scanners_met(struct compact_control *cc)
+{
+	return (cc->free_pfn >> pageblock_order)
+		<= (cc->migrate_pfn >> pageblock_order);
+}
+
+/*
  * Based on information in the current compact_control, find blocks
  * suitable for isolating free pages from and then isolate them.
  */
@@ -933,8 +981,7 @@ static void isolate_freepages(struct compact_control *cc)
 	 * pages on cc->migratepages. We stop searching if the migrate
 	 * and free page scanners meet or enough free pages are isolated.
 	 */
-	for (; block_start_pfn >= low_pfn &&
-			cc->nr_migratepages > cc->nr_freepages;
+	for (; block_start_pfn >= low_pfn;
 				block_end_pfn = block_start_pfn,
 				block_start_pfn -= pageblock_nr_pages,
 				isolate_start_pfn = block_start_pfn) {
@@ -966,6 +1013,8 @@ static void isolate_freepages(struct compact_control *cc)
 					block_end_pfn, freelist, false);
 
 		/*
+		 * If we isolated enough freepages, or aborted due to async
+		 * compaction being contended, terminate the loop.
 		 * Remember where the free scanner should restart next time,
 		 * which is where isolate_freepages_block() left off.
 		 * But if it scanned the whole pageblock, isolate_start_pfn
@@ -974,27 +1023,31 @@ static void isolate_freepages(struct compact_control *cc)
 		 * In that case we will however want to restart at the start
 		 * of the previous pageblock.
 		 */
-		cc->free_pfn = (isolate_start_pfn < block_end_pfn) ?
-				isolate_start_pfn :
-				block_start_pfn - pageblock_nr_pages;
-
-		/*
-		 * isolate_freepages_block() might have aborted due to async
-		 * compaction being contended
-		 */
-		if (cc->contended)
+		if ((cc->nr_freepages >= cc->nr_migratepages)
+							|| cc->contended) {
+			if (isolate_start_pfn >= block_end_pfn)
+				isolate_start_pfn =
+					block_start_pfn - pageblock_nr_pages;
 			break;
+		} else {
+			/*
+			 * isolate_freepages_block() should not terminate
+			 * prematurely unless contended, or isolated enough
+			 */
+			VM_BUG_ON(isolate_start_pfn < block_end_pfn);
+		}
 	}
 
 	/* split_free_page does not map the pages */
 	map_pages(freelist);
 
 	/*
-	 * If we crossed the migrate scanner, we want to keep it that way
-	 * so that compact_finished() may detect this
+	 * Record where the free scanner will restart next time. Either we
+	 * broke from the loop and set isolate_start_pfn based on the last
+	 * call to isolate_freepages_block(), or we met the migration scanner
+	 * and the loop terminated due to isolate_start_pfn < low_pfn
 	 */
-	if (block_start_pfn < low_pfn)
-		cc->free_pfn = cc->migrate_pfn;
+	cc->free_pfn = isolate_start_pfn;
 }
 
 /*
@@ -1062,6 +1115,7 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
 					struct compact_control *cc)
 {
 	unsigned long low_pfn, end_pfn;
+	unsigned long isolate_start_pfn;
 	struct page *page;
 	const isolate_mode_t isolate_mode =
 		(sysctl_compact_unevictable_allowed ? ISOLATE_UNEVICTABLE : 0) |
@@ -1110,6 +1164,7 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
 			continue;
 
 		/* Perform the isolation */
+		isolate_start_pfn = low_pfn;
 		low_pfn = isolate_migratepages_block(cc, low_pfn, end_pfn,
 								isolate_mode);
 
@@ -1119,6 +1174,15 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
 		}
 
 		/*
+		 * Record where we could have freed pages by migration and not
+		 * yet flushed them to buddy allocator.
+		 * - this is the lowest page that could have been isolated and
+		 * then freed by migration.
+		 */
+		if (cc->nr_migratepages && !cc->last_migrated_pfn)
+			cc->last_migrated_pfn = isolate_start_pfn;
+
+		/*
 		 * Either we isolated something and proceed with migration. Or
 		 * we failed and compact_zone should decide if we should
 		 * continue or not.
@@ -1127,12 +1191,8 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
 	}
 
 	acct_isolated(zone, cc);
-	/*
-	 * Record where migration scanner will be restarted. If we end up in
-	 * the same pageblock as the free scanner, make the scanners fully
-	 * meet so that compact_finished() terminates compaction.
-	 */
-	cc->migrate_pfn = (end_pfn <= cc->free_pfn) ? low_pfn : cc->free_pfn;
+	/* Record where migration scanner will be restarted. */
+	cc->migrate_pfn = low_pfn;
 
 	return cc->nr_migratepages ? ISOLATE_SUCCESS : ISOLATE_NONE;
 }
@@ -1147,11 +1207,9 @@ static int __compact_finished(struct zone *zone, struct compact_control *cc,
 		return COMPACT_PARTIAL;
 
 	/* Compaction run completes if the migrate and free scanner meet */
-	if (cc->free_pfn <= cc->migrate_pfn) {
+	if (compact_scanners_met(cc)) {
 		/* Let the next compaction start anew. */
-		zone->compact_cached_migrate_pfn[0] = zone->zone_start_pfn;
-		zone->compact_cached_migrate_pfn[1] = zone->zone_start_pfn;
-		zone->compact_cached_free_pfn = zone_end_pfn(zone);
+		reset_cached_positions(zone);
 
 		/*
 		 * Mark that the PG_migrate_skip information should be cleared
@@ -1295,7 +1353,6 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 	unsigned long end_pfn = zone_end_pfn(zone);
 	const int migratetype = gfpflags_to_migratetype(cc->gfp_mask);
 	const bool sync = cc->mode != MIGRATE_ASYNC;
-	unsigned long last_migrated_pfn = 0;
 
 	ret = compaction_suitable(zone, cc->order, cc->alloc_flags,
 							cc->classzone_idx);
@@ -1333,6 +1390,7 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 		zone->compact_cached_migrate_pfn[0] = cc->migrate_pfn;
 		zone->compact_cached_migrate_pfn[1] = cc->migrate_pfn;
 	}
+	cc->last_migrated_pfn = 0;
 
 	trace_mm_compaction_begin(start_pfn, cc->migrate_pfn,
 				cc->free_pfn, end_pfn, sync);
@@ -1342,7 +1400,6 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 	while ((ret = compact_finished(zone, cc, migratetype)) ==
 						COMPACT_CONTINUE) {
 		int err;
-		unsigned long isolate_start_pfn = cc->migrate_pfn;
 
 		switch (isolate_migratepages(zone, cc)) {
 		case ISOLATE_ABORT:
@@ -1376,22 +1433,12 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 			 * migrate_pages() may return -ENOMEM when scanners meet
 			 * and we want compact_finished() to detect it
 			 */
-			if (err == -ENOMEM && cc->free_pfn > cc->migrate_pfn) {
+			if (err == -ENOMEM && !compact_scanners_met(cc)) {
 				ret = COMPACT_PARTIAL;
 				goto out;
 			}
 		}
 
-		/*
-		 * Record where we could have freed pages by migration and not
-		 * yet flushed them to buddy allocator. We use the pfn that
-		 * isolate_migratepages() started from in this loop iteration
-		 * - this is the lowest page that could have been isolated and
-		 * then freed by migration.
-		 */
-		if (!last_migrated_pfn)
-			last_migrated_pfn = isolate_start_pfn;
-
 check_drain:
 		/*
 		 * Has the migration scanner moved away from the previous
@@ -1400,18 +1447,18 @@ check_drain:
 		 * compact_finished() can detect immediately if allocation
 		 * would succeed.
 		 */
-		if (cc->order > 0 && last_migrated_pfn) {
+		if (cc->order > 0 && cc->last_migrated_pfn) {
 			int cpu;
 			unsigned long current_block_start =
 				cc->migrate_pfn & ~((1UL << cc->order) - 1);
 
-			if (last_migrated_pfn < current_block_start) {
+			if (cc->last_migrated_pfn < current_block_start) {
 				cpu = get_cpu();
 				lru_add_drain_cpu(cpu);
 				drain_local_pages(zone);
 				put_cpu();
 				/* No more flushing until we migrate again */
-				last_migrated_pfn = 0;
+				cc->last_migrated_pfn = 0;
 			}
 		}
 
diff --git a/mm/dmapool.c b/mm/dmapool.c
index 59d10d1..71a8998 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -271,6 +271,9 @@ void dma_pool_destroy(struct dma_pool *pool)
 {
 	bool empty = false;
 
+	if (unlikely(!pool))
+		return;
+
 	mutex_lock(&pools_reg_lock);
 	mutex_lock(&pools_lock);
 	list_del(&pool->pools);
@@ -334,7 +337,7 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
 	/* pool_alloc_page() might sleep, so temporarily drop &pool->lock */
 	spin_unlock_irqrestore(&pool->lock, flags);
 
-	page = pool_alloc_page(pool, mem_flags);
+	page = pool_alloc_page(pool, mem_flags & (~__GFP_ZERO));
 	if (!page)
 		return NULL;
 
@@ -372,9 +375,14 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags,
 			break;
 		}
 	}
-	memset(retval, POOL_POISON_ALLOCATED, pool->size);
+	if (!(mem_flags & __GFP_ZERO))
+		memset(retval, POOL_POISON_ALLOCATED, pool->size);
 #endif
 	spin_unlock_irqrestore(&pool->lock, flags);
+
+	if (mem_flags & __GFP_ZERO)
+		memset(retval, 0, pool->size);
+
 	return retval;
 }
 EXPORT_SYMBOL(dma_pool_alloc);
diff --git a/mm/early_ioremap.c b/mm/early_ioremap.c
index 0cfadaf..23f744d 100644
--- a/mm/early_ioremap.c
+++ b/mm/early_ioremap.c
@@ -224,6 +224,28 @@ early_memremap_ro(resource_size_t phys_addr, unsigned long size)
 	return (__force void *)__early_ioremap(phys_addr, size, FIXMAP_PAGE_RO);
 }
 #endif
+
+#define MAX_MAP_CHUNK	(NR_FIX_BTMAPS << PAGE_SHIFT)
+
+void __init copy_from_early_mem(void *dest, phys_addr_t src, unsigned long size)
+{
+	unsigned long slop, clen;
+	char *p;
+
+	while (size) {
+		slop = src & ~PAGE_MASK;
+		clen = size;
+		if (clen > MAX_MAP_CHUNK - slop)
+			clen = MAX_MAP_CHUNK - slop;
+		p = early_memremap(src & PAGE_MASK, clen + slop);
+		memcpy(dest, p + slop, clen);
+		early_memunmap(p, clen + slop);
+		dest += clen;
+		src += clen;
+		size -= clen;
+	}
+}
+
 #else /* CONFIG_MMU */
 
 void __init __iomem *
diff --git a/mm/filemap.c b/mm/filemap.c
index 1283fc8..72940fb 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -674,7 +674,7 @@ struct page *__page_cache_alloc(gfp_t gfp)
 		do {
 			cpuset_mems_cookie = read_mems_allowed_begin();
 			n = cpuset_mem_spread_node();
-			page = alloc_pages_exact_node(n, gfp, 0);
+			page = __alloc_pages_node(n, gfp, 0);
 		} while (!page && read_mems_allowed_retry(cpuset_mems_cookie));
 
 		return page;
@@ -2473,21 +2473,6 @@ ssize_t generic_perform_write(struct file *file,
 						iov_iter_count(i));
 
 again:
-		/*
-		 * Bring in the user page that we will copy from _first_.
-		 * Otherwise there's a nasty deadlock on copying from the
-		 * same page as we're writing to, without it being marked
-		 * up-to-date.
-		 *
-		 * Not only is this an optimisation, but it is also required
-		 * to check that the address is actually valid, when atomic
-		 * usercopies are used, below.
-		 */
-		if (unlikely(iov_iter_fault_in_readable(i, bytes))) {
-			status = -EFAULT;
-			break;
-		}
-
 		status = a_ops->write_begin(file, mapping, pos, bytes, flags,
 						&page, &fsdata);
 		if (unlikely(status < 0))
@@ -2495,8 +2480,17 @@ again:
 
 		if (mapping_writably_mapped(mapping))
 			flush_dcache_page(page);
-
+		/*
+		 * 'page' is now locked.  If we are trying to copy from a
+		 * mapping of 'page' in userspace, the copy might fault and
+		 * would need PageUptodate() to complete.  But, page can not be
+		 * made Uptodate without acquiring the page lock, which we hold.
+		 * Deadlock.  Avoid with pagefault_disable().  Fix up below with
+		 * iov_iter_fault_in_readable().
+		 */
+		pagefault_disable();
 		copied = iov_iter_copy_from_user_atomic(page, i, offset, bytes);
+		pagefault_enable();
 		flush_dcache_page(page);
 
 		status = a_ops->write_end(file, mapping, pos, bytes, copied,
@@ -2519,6 +2513,14 @@ again:
 			 */
 			bytes = min_t(unsigned long, PAGE_CACHE_SIZE - offset,
 						iov_iter_single_seg_count(i));
+			/*
+			 * This is the fallback to recover if the copy from
+			 * userspace above faults.
+			 */
+			if (unlikely(iov_iter_fault_in_readable(i, bytes))) {
+				status = -EFAULT;
+				break;
+			}
 			goto again;
 		}
 		pos += copied;
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 279a818..b16279c 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -16,6 +16,7 @@
 #include <linux/swap.h>
 #include <linux/shrinker.h>
 #include <linux/mm_inline.h>
+#include <linux/dax.h>
 #include <linux/kthread.h>
 #include <linux/khugepaged.h>
 #include <linux/freezer.h>
@@ -105,7 +106,7 @@ static struct khugepaged_scan khugepaged_scan = {
 };
 
 
-static int set_recommended_min_free_kbytes(void)
+static void set_recommended_min_free_kbytes(void)
 {
 	struct zone *zone;
 	int nr_zones = 0;
@@ -140,7 +141,6 @@ static int set_recommended_min_free_kbytes(void)
 		min_free_kbytes = recommended_min;
 	}
 	setup_per_zone_wmarks();
-	return 0;
 }
 
 static int start_stop_khugepaged(void)
@@ -172,12 +172,7 @@ fail:
 static atomic_t huge_zero_refcount;
 struct page *huge_zero_page __read_mostly;
 
-static inline bool is_huge_zero_pmd(pmd_t pmd)
-{
-	return is_huge_zero_page(pmd_page(pmd));
-}
-
-static struct page *get_huge_zero_page(void)
+struct page *get_huge_zero_page(void)
 {
 	struct page *zero_page;
 retry:
@@ -794,16 +789,19 @@ static inline gfp_t alloc_hugepage_gfpmask(int defrag, gfp_t extra_gfp)
 }
 
 /* Caller must hold page table lock. */
-static void set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
+static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
 		struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd,
 		struct page *zero_page)
 {
 	pmd_t entry;
+	if (!pmd_none(*pmd))
+		return false;
 	entry = mk_pmd(zero_page, vma->vm_page_prot);
 	entry = pmd_mkhuge(entry);
 	pgtable_trans_huge_deposit(mm, pmd, pgtable);
 	set_pmd_at(mm, haddr, pmd, entry);
 	atomic_long_inc(&mm->nr_ptes);
+	return true;
 }
 
 int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -870,6 +868,49 @@ int do_huge_pmd_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
 					    flags);
 }
 
+static void insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
+		pmd_t *pmd, unsigned long pfn, pgprot_t prot, bool write)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	pmd_t entry;
+	spinlock_t *ptl;
+
+	ptl = pmd_lock(mm, pmd);
+	if (pmd_none(*pmd)) {
+		entry = pmd_mkhuge(pfn_pmd(pfn, prot));
+		if (write) {
+			entry = pmd_mkyoung(pmd_mkdirty(entry));
+			entry = maybe_pmd_mkwrite(entry, vma);
+		}
+		set_pmd_at(mm, addr, pmd, entry);
+		update_mmu_cache_pmd(vma, addr, pmd);
+	}
+	spin_unlock(ptl);
+}
+
+int vmf_insert_pfn_pmd(struct vm_area_struct *vma, unsigned long addr,
+			pmd_t *pmd, unsigned long pfn, bool write)
+{
+	pgprot_t pgprot = vma->vm_page_prot;
+	/*
+	 * If we had pmd_special, we could avoid all these restrictions,
+	 * but we need to be consistent with PTEs and architectures that
+	 * can't support a 'special' bit.
+	 */
+	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));
+	BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==
+						(VM_PFNMAP|VM_MIXEDMAP));
+	BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));
+	BUG_ON((vma->vm_flags & VM_MIXEDMAP) && pfn_valid(pfn));
+
+	if (addr < vma->vm_start || addr >= vma->vm_end)
+		return VM_FAULT_SIGBUS;
+	if (track_pfn_insert(vma, &pgprot, pfn))
+		return VM_FAULT_SIGBUS;
+	insert_pfn_pmd(vma, addr, pmd, pfn, pgprot, write);
+	return VM_FAULT_NOPAGE;
+}
+
 int copy_huge_pmd(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 		  pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long addr,
 		  struct vm_area_struct *vma)
@@ -1414,41 +1455,41 @@ out:
 int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
 		 pmd_t *pmd, unsigned long addr)
 {
+	pmd_t orig_pmd;
 	spinlock_t *ptl;
-	int ret = 0;
 
-	if (__pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
-		struct page *page;
-		pgtable_t pgtable;
-		pmd_t orig_pmd;
-		/*
-		 * For architectures like ppc64 we look at deposited pgtable
-		 * when calling pmdp_huge_get_and_clear. So do the
-		 * pgtable_trans_huge_withdraw after finishing pmdp related
-		 * operations.
-		 */
-		orig_pmd = pmdp_huge_get_and_clear_full(tlb->mm, addr, pmd,
-							tlb->fullmm);
-		tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
-		pgtable = pgtable_trans_huge_withdraw(tlb->mm, pmd);
-		if (is_huge_zero_pmd(orig_pmd)) {
-			atomic_long_dec(&tlb->mm->nr_ptes);
-			spin_unlock(ptl);
+	if (__pmd_trans_huge_lock(pmd, vma, &ptl) != 1)
+		return 0;
+	/*
+	 * For architectures like ppc64 we look at deposited pgtable
+	 * when calling pmdp_huge_get_and_clear. So do the
+	 * pgtable_trans_huge_withdraw after finishing pmdp related
+	 * operations.
+	 */
+	orig_pmd = pmdp_huge_get_and_clear_full(tlb->mm, addr, pmd,
+			tlb->fullmm);
+	tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
+	if (vma_is_dax(vma)) {
+		spin_unlock(ptl);
+		if (is_huge_zero_pmd(orig_pmd))
 			put_huge_zero_page();
-		} else {
-			page = pmd_page(orig_pmd);
-			page_remove_rmap(page);
-			VM_BUG_ON_PAGE(page_mapcount(page) < 0, page);
-			add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
-			VM_BUG_ON_PAGE(!PageHead(page), page);
-			atomic_long_dec(&tlb->mm->nr_ptes);
-			spin_unlock(ptl);
-			tlb_remove_page(tlb, page);
-		}
-		pte_free(tlb->mm, pgtable);
-		ret = 1;
+	} else if (is_huge_zero_pmd(orig_pmd)) {
+		pte_free(tlb->mm, pgtable_trans_huge_withdraw(tlb->mm, pmd));
+		atomic_long_dec(&tlb->mm->nr_ptes);
+		spin_unlock(ptl);
+		put_huge_zero_page();
+	} else {
+		struct page *page = pmd_page(orig_pmd);
+		page_remove_rmap(page);
+		VM_BUG_ON_PAGE(page_mapcount(page) < 0, page);
+		add_mm_counter(tlb->mm, MM_ANONPAGES, -HPAGE_PMD_NR);
+		VM_BUG_ON_PAGE(!PageHead(page), page);
+		pte_free(tlb->mm, pgtable_trans_huge_withdraw(tlb->mm, pmd));
+		atomic_long_dec(&tlb->mm->nr_ptes);
+		spin_unlock(ptl);
+		tlb_remove_page(tlb, page);
 	}
-	return ret;
+	return 1;
 }
 
 int move_huge_pmd(struct vm_area_struct *vma, struct vm_area_struct *new_vma,
@@ -2285,8 +2326,12 @@ static void __collapse_huge_page_copy(pte_t *pte, struct page *page,
 
 static void khugepaged_alloc_sleep(void)
 {
-	wait_event_freezable_timeout(khugepaged_wait, false,
-			msecs_to_jiffies(khugepaged_alloc_sleep_millisecs));
+	DEFINE_WAIT(wait);
+
+	add_wait_queue(&khugepaged_wait, &wait);
+	freezable_schedule_timeout_interruptible(
+		msecs_to_jiffies(khugepaged_alloc_sleep_millisecs));
+	remove_wait_queue(&khugepaged_wait, &wait);
 }
 
 static int khugepaged_node_load[MAX_NUMNODES];
@@ -2373,7 +2418,7 @@ khugepaged_alloc_page(struct page **hpage, gfp_t gfp, struct mm_struct *mm,
 	 */
 	up_read(&mm->mmap_sem);
 
-	*hpage = alloc_pages_exact_node(node, gfp, HPAGE_PMD_ORDER);
+	*hpage = __alloc_pages_node(node, gfp, HPAGE_PMD_ORDER);
 	if (unlikely(!*hpage)) {
 		count_vm_event(THP_COLLAPSE_ALLOC_FAILED);
 		*hpage = ERR_PTR(-ENOMEM);
@@ -2911,7 +2956,7 @@ void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address,
 		pmd_t *pmd)
 {
 	spinlock_t *ptl;
-	struct page *page;
+	struct page *page = NULL;
 	struct mm_struct *mm = vma->vm_mm;
 	unsigned long haddr = address & HPAGE_PMD_MASK;
 	unsigned long mmun_start;	/* For mmu_notifiers */
@@ -2924,25 +2969,27 @@ void __split_huge_page_pmd(struct vm_area_struct *vma, unsigned long address,
 again:
 	mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
 	ptl = pmd_lock(mm, pmd);
-	if (unlikely(!pmd_trans_huge(*pmd))) {
-		spin_unlock(ptl);
-		mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
-		return;
-	}
-	if (is_huge_zero_pmd(*pmd)) {
+	if (unlikely(!pmd_trans_huge(*pmd)))
+		goto unlock;
+	if (vma_is_dax(vma)) {
+		pmd_t _pmd = pmdp_huge_clear_flush_notify(vma, haddr, pmd);
+		if (is_huge_zero_pmd(_pmd))
+			put_huge_zero_page();
+	} else if (is_huge_zero_pmd(*pmd)) {
 		__split_huge_zero_page_pmd(vma, haddr, pmd);
-		spin_unlock(ptl);
-		mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
-		return;
+	} else {
+		page = pmd_page(*pmd);
+		VM_BUG_ON_PAGE(!page_count(page), page);
+		get_page(page);
 	}
-	page = pmd_page(*pmd);
-	VM_BUG_ON_PAGE(!page_count(page), page);
-	get_page(page);
+ unlock:
 	spin_unlock(ptl);
 	mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
 
-	split_huge_page(page);
+	if (!page)
+		return;
 
+	split_huge_page(page);
 	put_page(page);
 
 	/*
@@ -2991,7 +3038,7 @@ static void split_huge_page_address(struct mm_struct *mm,
 	split_huge_page_pmd_mm(mm, address, pmd);
 }
 
-void __vma_adjust_trans_huge(struct vm_area_struct *vma,
+void vma_adjust_trans_huge(struct vm_area_struct *vma,
 			     unsigned long start,
 			     unsigned long end,
 			     long adjust_next)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 51ae41d..999fb0a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -64,7 +64,7 @@ DEFINE_SPINLOCK(hugetlb_lock);
  * prevent spurious OOMs when the hugepage pool is fully utilized.
  */
 static int num_fault_mutexes;
-static struct mutex *htlb_fault_mutex_table ____cacheline_aligned_in_smp;
+struct mutex *hugetlb_fault_mutex_table ____cacheline_aligned_in_smp;
 
 /* Forward declaration */
 static int hugetlb_acct_memory(struct hstate *h, long delta);
@@ -240,11 +240,14 @@ struct file_region {
 
 /*
  * Add the huge page range represented by [f, t) to the reserve
- * map.  Existing regions will be expanded to accommodate the
- * specified range.  We know only existing regions need to be
- * expanded, because region_add is only called after region_chg
- * with the same range.  If a new file_region structure must
- * be allocated, it is done in region_chg.
+ * map.  In the normal case, existing regions will be expanded
+ * to accommodate the specified range.  Sufficient regions should
+ * exist for expansion due to the previous call to region_chg
+ * with the same range.  However, it is possible that region_del
+ * could have been called after region_chg and modifed the map
+ * in such a way that no region exists to be expanded.  In this
+ * case, pull a region descriptor from the cache associated with
+ * the map and use that for the new range.
  *
  * Return the number of new huge pages added to the map.  This
  * number is greater than or equal to zero.
@@ -261,6 +264,28 @@ static long region_add(struct resv_map *resv, long f, long t)
 		if (f <= rg->to)
 			break;
 
+	/*
+	 * If no region exists which can be expanded to include the
+	 * specified range, the list must have been modified by an
+	 * interleving call to region_del().  Pull a region descriptor
+	 * from the cache and use it for this range.
+	 */
+	if (&rg->link == head || t < rg->from) {
+		VM_BUG_ON(resv->region_cache_count <= 0);
+
+		resv->region_cache_count--;
+		nrg = list_first_entry(&resv->region_cache, struct file_region,
+					link);
+		list_del(&nrg->link);
+
+		nrg->from = f;
+		nrg->to = t;
+		list_add(&nrg->link, rg->link.prev);
+
+		add += t - f;
+		goto out_locked;
+	}
+
 	/* Round our left edge to the current segment if it encloses us. */
 	if (f > rg->from)
 		f = rg->from;
@@ -294,6 +319,8 @@ static long region_add(struct resv_map *resv, long f, long t)
 	add += t - nrg->to;		/* Added to end of region */
 	nrg->to = t;
 
+out_locked:
+	resv->adds_in_progress--;
 	spin_unlock(&resv->lock);
 	VM_BUG_ON(add < 0);
 	return add;
@@ -312,11 +339,14 @@ static long region_add(struct resv_map *resv, long f, long t)
  * so that the subsequent region_add call will have all the
  * regions it needs and will not fail.
  *
- * Returns the number of huge pages that need to be added
- * to the existing reservation map for the range [f, t).
- * This number is greater or equal to zero.  -ENOMEM is
- * returned if a new file_region structure is needed and can
- * not be allocated.
+ * Upon entry, region_chg will also examine the cache of region descriptors
+ * associated with the map.  If there are not enough descriptors cached, one
+ * will be allocated for the in progress add operation.
+ *
+ * Returns the number of huge pages that need to be added to the existing
+ * reservation map for the range [f, t).  This number is greater or equal to
+ * zero.  -ENOMEM is returned if a new file_region structure or cache entry
+ * is needed and can not be allocated.
  */
 static long region_chg(struct resv_map *resv, long f, long t)
 {
@@ -326,6 +356,31 @@ static long region_chg(struct resv_map *resv, long f, long t)
 
 retry:
 	spin_lock(&resv->lock);
+retry_locked:
+	resv->adds_in_progress++;
+
+	/*
+	 * Check for sufficient descriptors in the cache to accommodate
+	 * the number of in progress add operations.
+	 */
+	if (resv->adds_in_progress > resv->region_cache_count) {
+		struct file_region *trg;
+
+		VM_BUG_ON(resv->adds_in_progress - resv->region_cache_count > 1);
+		/* Must drop lock to allocate a new descriptor. */
+		resv->adds_in_progress--;
+		spin_unlock(&resv->lock);
+
+		trg = kmalloc(sizeof(*trg), GFP_KERNEL);
+		if (!trg)
+			return -ENOMEM;
+
+		spin_lock(&resv->lock);
+		list_add(&trg->link, &resv->region_cache);
+		resv->region_cache_count++;
+		goto retry_locked;
+	}
+
 	/* Locate the region we are before or in. */
 	list_for_each_entry(rg, head, link)
 		if (f <= rg->to)
@@ -336,6 +391,7 @@ retry:
 	 * size such that we can guarantee to record the reservation. */
 	if (&rg->link == head || t < rg->from) {
 		if (!nrg) {
+			resv->adds_in_progress--;
 			spin_unlock(&resv->lock);
 			nrg = kmalloc(sizeof(*nrg), GFP_KERNEL);
 			if (!nrg)
@@ -385,43 +441,131 @@ out_nrg:
 }
 
 /*
- * Truncate the reserve map at index 'end'.  Modify/truncate any
- * region which contains end.  Delete any regions past end.
- * Return the number of huge pages removed from the map.
+ * Abort the in progress add operation.  The adds_in_progress field
+ * of the resv_map keeps track of the operations in progress between
+ * calls to region_chg and region_add.  Operations are sometimes
+ * aborted after the call to region_chg.  In such cases, region_abort
+ * is called to decrement the adds_in_progress counter.
+ *
+ * NOTE: The range arguments [f, t) are not needed or used in this
+ * routine.  They are kept to make reading the calling code easier as
+ * arguments will match the associated region_chg call.
  */
-static long region_truncate(struct resv_map *resv, long end)
+static void region_abort(struct resv_map *resv, long f, long t)
+{
+	spin_lock(&resv->lock);
+	VM_BUG_ON(!resv->region_cache_count);
+	resv->adds_in_progress--;
+	spin_unlock(&resv->lock);
+}
+
+/*
+ * Delete the specified range [f, t) from the reserve map.  If the
+ * t parameter is LONG_MAX, this indicates that ALL regions after f
+ * should be deleted.  Locate the regions which intersect [f, t)
+ * and either trim, delete or split the existing regions.
+ *
+ * Returns the number of huge pages deleted from the reserve map.
+ * In the normal case, the return value is zero or more.  In the
+ * case where a region must be split, a new region descriptor must
+ * be allocated.  If the allocation fails, -ENOMEM will be returned.
+ * NOTE: If the parameter t == LONG_MAX, then we will never split
+ * a region and possibly return -ENOMEM.  Callers specifying
+ * t == LONG_MAX do not need to check for -ENOMEM error.
+ */
+static long region_del(struct resv_map *resv, long f, long t)
 {
 	struct list_head *head = &resv->regions;
 	struct file_region *rg, *trg;
-	long chg = 0;
+	struct file_region *nrg = NULL;
+	long del = 0;
 
+retry:
 	spin_lock(&resv->lock);
-	/* Locate the region we are either in or before. */
-	list_for_each_entry(rg, head, link)
-		if (end <= rg->to)
+	list_for_each_entry_safe(rg, trg, head, link) {
+		if (rg->to <= f)
+			continue;
+		if (rg->from >= t)
 			break;
-	if (&rg->link == head)
-		goto out;
 
-	/* If we are in the middle of a region then adjust it. */
-	if (end > rg->from) {
-		chg = rg->to - end;
-		rg->to = end;
-		rg = list_entry(rg->link.next, typeof(*rg), link);
-	}
+		if (f > rg->from && t < rg->to) { /* Must split region */
+			/*
+			 * Check for an entry in the cache before dropping
+			 * lock and attempting allocation.
+			 */
+			if (!nrg &&
+			    resv->region_cache_count > resv->adds_in_progress) {
+				nrg = list_first_entry(&resv->region_cache,
+							struct file_region,
+							link);
+				list_del(&nrg->link);
+				resv->region_cache_count--;
+			}
 
-	/* Drop any remaining regions. */
-	list_for_each_entry_safe(rg, trg, rg->link.prev, link) {
-		if (&rg->link == head)
+			if (!nrg) {
+				spin_unlock(&resv->lock);
+				nrg = kmalloc(sizeof(*nrg), GFP_KERNEL);
+				if (!nrg)
+					return -ENOMEM;
+				goto retry;
+			}
+
+			del += t - f;
+
+			/* New entry for end of split region */
+			nrg->from = t;
+			nrg->to = rg->to;
+			INIT_LIST_HEAD(&nrg->link);
+
+			/* Original entry is trimmed */
+			rg->to = f;
+
+			list_add(&nrg->link, &rg->link);
+			nrg = NULL;
 			break;
-		chg += rg->to - rg->from;
-		list_del(&rg->link);
-		kfree(rg);
+		}
+
+		if (f <= rg->from && t >= rg->to) { /* Remove entire region */
+			del += rg->to - rg->from;
+			list_del(&rg->link);
+			kfree(rg);
+			continue;
+		}
+
+		if (f <= rg->from) {	/* Trim beginning of region */
+			del += t - rg->from;
+			rg->from = t;
+		} else {		/* Trim end of region */
+			del += rg->to - f;
+			rg->to = f;
+		}
 	}
 
-out:
 	spin_unlock(&resv->lock);
-	return chg;
+	kfree(nrg);
+	return del;
+}
+
+/*
+ * A rare out of memory error was encountered which prevented removal of
+ * the reserve map region for a page.  The huge page itself was free'ed
+ * and removed from the page cache.  This routine will adjust the subpool
+ * usage count, and the global reserve count if needed.  By incrementing
+ * these counts, the reserve map entry which could not be deleted will
+ * appear as a "reserved" entry instead of simply dangling with incorrect
+ * counts.
+ */
+void hugetlb_fix_reserve_counts(struct inode *inode, bool restore_reserve)
+{
+	struct hugepage_subpool *spool = subpool_inode(inode);
+	long rsv_adjust;
+
+	rsv_adjust = hugepage_subpool_get_pages(spool, 1);
+	if (restore_reserve && rsv_adjust) {
+		struct hstate *h = hstate_inode(inode);
+
+		hugetlb_acct_memory(h, 1);
+	}
 }
 
 /*
@@ -544,22 +688,44 @@ static void set_vma_private_data(struct vm_area_struct *vma,
 struct resv_map *resv_map_alloc(void)
 {
 	struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL);
-	if (!resv_map)
+	struct file_region *rg = kmalloc(sizeof(*rg), GFP_KERNEL);
+
+	if (!resv_map || !rg) {
+		kfree(resv_map);
+		kfree(rg);
 		return NULL;
+	}
 
 	kref_init(&resv_map->refs);
 	spin_lock_init(&resv_map->lock);
 	INIT_LIST_HEAD(&resv_map->regions);
 
+	resv_map->adds_in_progress = 0;
+
+	INIT_LIST_HEAD(&resv_map->region_cache);
+	list_add(&rg->link, &resv_map->region_cache);
+	resv_map->region_cache_count = 1;
+
 	return resv_map;
 }
 
 void resv_map_release(struct kref *ref)
 {
 	struct resv_map *resv_map = container_of(ref, struct resv_map, refs);
+	struct list_head *head = &resv_map->region_cache;
+	struct file_region *rg, *trg;
 
 	/* Clear out any active regions before we release the map. */
-	region_truncate(resv_map, 0);
+	region_del(resv_map, 0, LONG_MAX);
+
+	/* ... and any entries left in the cache */
+	list_for_each_entry_safe(rg, trg, head, link) {
+		list_del(&rg->link);
+		kfree(rg);
+	}
+
+	VM_BUG_ON(resv_map->adds_in_progress);
+
 	kfree(resv_map);
 }
 
@@ -635,8 +801,19 @@ static bool vma_has_reserves(struct vm_area_struct *vma, long chg)
 	}
 
 	/* Shared mappings always use reserves */
-	if (vma->vm_flags & VM_MAYSHARE)
-		return true;
+	if (vma->vm_flags & VM_MAYSHARE) {
+		/*
+		 * We know VM_NORESERVE is not set.  Therefore, there SHOULD
+		 * be a region map for all pages.  The only situation where
+		 * there is no region map is if a hole was punched via
+		 * fallocate.  In this case, there really are no reverves to
+		 * use.  This situation is indicated if chg != 0.
+		 */
+		if (chg)
+			return false;
+		else
+			return true;
+	}
 
 	/*
 	 * Only the process that called mmap() has reserves for
@@ -1154,7 +1331,7 @@ static struct page *alloc_fresh_huge_page_node(struct hstate *h, int nid)
 {
 	struct page *page;
 
-	page = alloc_pages_exact_node(nid,
+	page = __alloc_pages_node(nid,
 		htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE|
 						__GFP_REPEAT|__GFP_NOWARN,
 		huge_page_order(h));
@@ -1306,7 +1483,7 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid)
 				   __GFP_REPEAT|__GFP_NOWARN,
 				   huge_page_order(h));
 	else
-		page = alloc_pages_exact_node(nid,
+		page = __alloc_pages_node(nid,
 			htlb_alloc_mask(h)|__GFP_COMP|__GFP_THISNODE|
 			__GFP_REPEAT|__GFP_NOWARN, huge_page_order(h));
 
@@ -1473,16 +1650,19 @@ static void return_unused_surplus_pages(struct hstate *h,
 	}
 }
 
+
 /*
- * vma_needs_reservation and vma_commit_reservation are used by the huge
- * page allocation routines to manage reservations.
+ * vma_needs_reservation, vma_commit_reservation and vma_end_reservation
+ * are used by the huge page allocation routines to manage reservations.
  *
  * vma_needs_reservation is called to determine if the huge page at addr
  * within the vma has an associated reservation.  If a reservation is
  * needed, the value 1 is returned.  The caller is then responsible for
  * managing the global reservation and subpool usage counts.  After
  * the huge page has been allocated, vma_commit_reservation is called
- * to add the page to the reservation map.
+ * to add the page to the reservation map.  If the page allocation fails,
+ * the reservation must be ended instead of committed.  vma_end_reservation
+ * is called in such cases.
  *
  * In the normal case, vma_commit_reservation returns the same value
  * as the preceding vma_needs_reservation call.  The only time this
@@ -1490,9 +1670,14 @@ static void return_unused_surplus_pages(struct hstate *h,
  * is the responsibility of the caller to notice the difference and
  * take appropriate action.
  */
+enum vma_resv_mode {
+	VMA_NEEDS_RESV,
+	VMA_COMMIT_RESV,
+	VMA_END_RESV,
+};
 static long __vma_reservation_common(struct hstate *h,
 				struct vm_area_struct *vma, unsigned long addr,
-				bool commit)
+				enum vma_resv_mode mode)
 {
 	struct resv_map *resv;
 	pgoff_t idx;
@@ -1503,10 +1688,20 @@ static long __vma_reservation_common(struct hstate *h,
 		return 1;
 
 	idx = vma_hugecache_offset(h, vma, addr);
-	if (commit)
-		ret = region_add(resv, idx, idx + 1);
-	else
+	switch (mode) {
+	case VMA_NEEDS_RESV:
 		ret = region_chg(resv, idx, idx + 1);
+		break;
+	case VMA_COMMIT_RESV:
+		ret = region_add(resv, idx, idx + 1);
+		break;
+	case VMA_END_RESV:
+		region_abort(resv, idx, idx + 1);
+		ret = 0;
+		break;
+	default:
+		BUG();
+	}
 
 	if (vma->vm_flags & VM_MAYSHARE)
 		return ret;
@@ -1517,47 +1712,79 @@ static long __vma_reservation_common(struct hstate *h,
 static long vma_needs_reservation(struct hstate *h,
 			struct vm_area_struct *vma, unsigned long addr)
 {
-	return __vma_reservation_common(h, vma, addr, false);
+	return __vma_reservation_common(h, vma, addr, VMA_NEEDS_RESV);
 }
 
 static long vma_commit_reservation(struct hstate *h,
 			struct vm_area_struct *vma, unsigned long addr)
 {
-	return __vma_reservation_common(h, vma, addr, true);
+	return __vma_reservation_common(h, vma, addr, VMA_COMMIT_RESV);
+}
+
+static void vma_end_reservation(struct hstate *h,
+			struct vm_area_struct *vma, unsigned long addr)
+{
+	(void)__vma_reservation_common(h, vma, addr, VMA_END_RESV);
 }
 
-static struct page *alloc_huge_page(struct vm_area_struct *vma,
+struct page *alloc_huge_page(struct vm_area_struct *vma,
 				    unsigned long addr, int avoid_reserve)
 {
 	struct hugepage_subpool *spool = subpool_vma(vma);
 	struct hstate *h = hstate_vma(vma);
 	struct page *page;
-	long chg, commit;
+	long map_chg, map_commit;
+	long gbl_chg;
 	int ret, idx;
 	struct hugetlb_cgroup *h_cg;
 
 	idx = hstate_index(h);
 	/*
-	 * Processes that did not create the mapping will have no
-	 * reserves and will not have accounted against subpool
-	 * limit. Check that the subpool limit can be made before
-	 * satisfying the allocation MAP_NORESERVE mappings may also
-	 * need pages and subpool limit allocated allocated if no reserve
-	 * mapping overlaps.
+	 * Examine the region/reserve map to determine if the process
+	 * has a reservation for the page to be allocated.  A return
+	 * code of zero indicates a reservation exists (no change).
 	 */
-	chg = vma_needs_reservation(h, vma, addr);
-	if (chg < 0)
+	map_chg = gbl_chg = vma_needs_reservation(h, vma, addr);
+	if (map_chg < 0)
 		return ERR_PTR(-ENOMEM);
-	if (chg || avoid_reserve)
-		if (hugepage_subpool_get_pages(spool, 1) < 0)
+
+	/*
+	 * Processes that did not create the mapping will have no
+	 * reserves as indicated by the region/reserve map. Check
+	 * that the allocation will not exceed the subpool limit.
+	 * Allocations for MAP_NORESERVE mappings also need to be
+	 * checked against any subpool limit.
+	 */
+	if (map_chg || avoid_reserve) {
+		gbl_chg = hugepage_subpool_get_pages(spool, 1);
+		if (gbl_chg < 0) {
+			vma_end_reservation(h, vma, addr);
 			return ERR_PTR(-ENOSPC);
+		}
+
+		/*
+		 * Even though there was no reservation in the region/reserve
+		 * map, there could be reservations associated with the
+		 * subpool that can be used.  This would be indicated if the
+		 * return value of hugepage_subpool_get_pages() is zero.
+		 * However, if avoid_reserve is specified we still avoid even
+		 * the subpool reservations.
+		 */
+		if (avoid_reserve)
+			gbl_chg = 1;
+	}
 
 	ret = hugetlb_cgroup_charge_cgroup(idx, pages_per_huge_page(h), &h_cg);
 	if (ret)
 		goto out_subpool_put;
 
 	spin_lock(&hugetlb_lock);
-	page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, chg);
+	/*
+	 * glb_chg is passed to indicate whether or not a page must be taken
+	 * from the global free pool (global change).  gbl_chg == 0 indicates
+	 * a reservation exists for the allocation.
+	 */
+	page = dequeue_huge_page_vma(h, vma, addr, avoid_reserve, gbl_chg);
 	if (!page) {
 		spin_unlock(&hugetlb_lock);
 		page = alloc_buddy_huge_page(h, NUMA_NO_NODE);
@@ -1573,8 +1800,8 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 
 	set_page_private(page, (unsigned long)spool);
 
-	commit = vma_commit_reservation(h, vma, addr);
-	if (unlikely(chg > commit)) {
+	map_commit = vma_commit_reservation(h, vma, addr);
+	if (unlikely(map_chg > map_commit)) {
 		/*
 		 * The page was added to the reservation map between
 		 * vma_needs_reservation and vma_commit_reservation.
@@ -1594,8 +1821,9 @@ static struct page *alloc_huge_page(struct vm_area_struct *vma,
 out_uncharge_cgroup:
 	hugetlb_cgroup_uncharge_cgroup(idx, pages_per_huge_page(h), h_cg);
 out_subpool_put:
-	if (chg || avoid_reserve)
+	if (map_chg || avoid_reserve)
 		hugepage_subpool_put_pages(spool, 1);
+	vma_end_reservation(h, vma, addr);
 	return ERR_PTR(-ENOSPC);
 }
 
@@ -2311,7 +2539,7 @@ static void __exit hugetlb_exit(void)
 	}
 
 	kobject_put(hugepages_kobj);
-	kfree(htlb_fault_mutex_table);
+	kfree(hugetlb_fault_mutex_table);
 }
 module_exit(hugetlb_exit);
 
@@ -2344,12 +2572,12 @@ static int __init hugetlb_init(void)
 #else
 	num_fault_mutexes = 1;
 #endif
-	htlb_fault_mutex_table =
+	hugetlb_fault_mutex_table =
 		kmalloc(sizeof(struct mutex) * num_fault_mutexes, GFP_KERNEL);
-	BUG_ON(!htlb_fault_mutex_table);
+	BUG_ON(!hugetlb_fault_mutex_table);
 
 	for (i = 0; i < num_fault_mutexes; i++)
-		mutex_init(&htlb_fault_mutex_table[i]);
+		mutex_init(&hugetlb_fault_mutex_table[i]);
 	return 0;
 }
 module_init(hugetlb_init);
@@ -3147,6 +3375,23 @@ static bool hugetlbfs_pagecache_present(struct hstate *h,
 	return page != NULL;
 }
 
+int huge_add_to_page_cache(struct page *page, struct address_space *mapping,
+			   pgoff_t idx)
+{
+	struct inode *inode = mapping->host;
+	struct hstate *h = hstate_inode(inode);
+	int err = add_to_page_cache(page, mapping, idx, GFP_KERNEL);
+
+	if (err)
+		return err;
+	ClearPagePrivate(page);
+
+	spin_lock(&inode->i_lock);
+	inode->i_blocks += blocks_per_huge_page(h);
+	spin_unlock(&inode->i_lock);
+	return 0;
+}
+
 static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
 			   struct address_space *mapping, pgoff_t idx,
 			   unsigned long address, pte_t *ptep, unsigned int flags)
@@ -3194,21 +3439,13 @@ retry:
 		set_page_huge_active(page);
 
 		if (vma->vm_flags & VM_MAYSHARE) {
-			int err;
-			struct inode *inode = mapping->host;
-
-			err = add_to_page_cache(page, mapping, idx, GFP_KERNEL);
+			int err = huge_add_to_page_cache(page, mapping, idx);
 			if (err) {
 				put_page(page);
 				if (err == -EEXIST)
 					goto retry;
 				goto out;
 			}
-			ClearPagePrivate(page);
-
-			spin_lock(&inode->i_lock);
-			inode->i_blocks += blocks_per_huge_page(h);
-			spin_unlock(&inode->i_lock);
 		} else {
 			lock_page(page);
 			if (unlikely(anon_vma_prepare(vma))) {
@@ -3236,11 +3473,14 @@ retry:
 	 * any allocations necessary to record that reservation occur outside
 	 * the spinlock.
 	 */
-	if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED))
+	if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
 		if (vma_needs_reservation(h, vma, address) < 0) {
 			ret = VM_FAULT_OOM;
 			goto backout_unlocked;
 		}
+		/* Just decrements count, does not deallocate */
+		vma_end_reservation(h, vma, address);
+	}
 
 	ptl = huge_pte_lockptr(h, mm, ptep);
 	spin_lock(ptl);
@@ -3280,7 +3520,7 @@ backout_unlocked:
 }
 
 #ifdef CONFIG_SMP
-static u32 fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
+u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
 			    struct vm_area_struct *vma,
 			    struct address_space *mapping,
 			    pgoff_t idx, unsigned long address)
@@ -3305,7 +3545,7 @@ static u32 fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
  * For uniprocesor systems we always use a single mutex, so just
  * return 0 and avoid the hashing overhead.
  */
-static u32 fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
+u32 hugetlb_fault_mutex_hash(struct hstate *h, struct mm_struct *mm,
 			    struct vm_area_struct *vma,
 			    struct address_space *mapping,
 			    pgoff_t idx, unsigned long address)
@@ -3353,8 +3593,8 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 	 * get spurious allocation failures if two CPUs race to instantiate
 	 * the same page in the page cache.
 	 */
-	hash = fault_mutex_hash(h, mm, vma, mapping, idx, address);
-	mutex_lock(&htlb_fault_mutex_table[hash]);
+	hash = hugetlb_fault_mutex_hash(h, mm, vma, mapping, idx, address);
+	mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 	entry = huge_ptep_get(ptep);
 	if (huge_pte_none(entry)) {
@@ -3387,6 +3627,8 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 			ret = VM_FAULT_OOM;
 			goto out_mutex;
 		}
+		/* Just decrements count, does not deallocate */
+		vma_end_reservation(h, vma, address);
 
 		if (!(vma->vm_flags & VM_MAYSHARE))
 			pagecache_page = hugetlbfs_pagecache_page(h,
@@ -3437,7 +3679,7 @@ out_ptl:
 		put_page(pagecache_page);
 	}
 out_mutex:
-	mutex_unlock(&htlb_fault_mutex_table[hash]);
+	mutex_unlock(&hugetlb_fault_mutex_table[hash]);
 	/*
 	 * Generally it's safe to hold refcount during waiting page lock. But
 	 * here we just wait to defer the next page fault to avoid busy loop and
@@ -3726,12 +3968,15 @@ int hugetlb_reserve_pages(struct inode *inode,
 	}
 	return 0;
 out_err:
+	if (!vma || vma->vm_flags & VM_MAYSHARE)
+		region_abort(resv_map, from, to);
 	if (vma && is_vma_resv_set(vma, HPAGE_RESV_OWNER))
 		kref_put(&resv_map->refs, resv_map_release);
 	return ret;
 }
 
-void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
+long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
+								long freed)
 {
 	struct hstate *h = hstate_inode(inode);
 	struct resv_map *resv_map = inode_resv_map(inode);
@@ -3739,8 +3984,17 @@ void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
 	struct hugepage_subpool *spool = subpool_inode(inode);
 	long gbl_reserve;
 
-	if (resv_map)
-		chg = region_truncate(resv_map, offset);
+	if (resv_map) {
+		chg = region_del(resv_map, start, end);
+		/*
+		 * region_del() can fail in the rare case where a region
+		 * must be split and another region descriptor can not be
+		 * allocated.  If end == LONG_MAX, it will not fail.
+		 */
+		if (chg < 0)
+			return chg;
+	}
+
 	spin_lock(&inode->i_lock);
 	inode->i_blocks -= (blocks_per_huge_page(h) * freed);
 	spin_unlock(&inode->i_lock);
@@ -3751,6 +4005,8 @@ void hugetlb_unreserve_pages(struct inode *inode, long offset, long freed)
 	 */
 	gbl_reserve = hugepage_subpool_put_pages(spool, (chg - freed));
 	hugetlb_acct_memory(h, -gbl_reserve);
+
+	return 0;
 }
 
 #ifdef CONFIG_ARCH_WANT_HUGE_PMD_SHARE
diff --git a/mm/hwpoison-inject.c b/mm/hwpoison-inject.c
index bf73ac1..aeba0ed 100644
--- a/mm/hwpoison-inject.c
+++ b/mm/hwpoison-inject.c
@@ -58,7 +58,7 @@ inject:
 	pr_info("Injecting memory failure at pfn %#lx\n", pfn);
 	return memory_failure(pfn, 18, MF_COUNT_INCREASED);
 put_out:
-	put_page(p);
+	put_hwpoison_page(p);
 	return 0;
 }
 
diff --git a/mm/internal.h b/mm/internal.h
index 1195dd2..bc0fa9a 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -182,6 +182,7 @@ struct compact_control {
 	unsigned long nr_migratepages;	/* Number of pages to migrate */
 	unsigned long free_pfn;		/* isolate_freepages search base */
 	unsigned long migrate_pfn;	/* isolate_migratepages search base */
+	unsigned long last_migrated_pfn;/* Not yet flushed page being freed */
 	enum migrate_mode mode;		/* Async or sync migration mode */
 	bool ignore_skip_hint;		/* Scan blocks even if marked skip */
 	int order;			/* order a direct compactor needs */
diff --git a/mm/kmemleak.c b/mm/kmemleak.c
index cf79f11..f532f6a 100644
--- a/mm/kmemleak.c
+++ b/mm/kmemleak.c
@@ -838,6 +838,7 @@ static void __init log_early(int op_type, const void *ptr, size_t size,
 	}
 
 	if (crt_early_log >= ARRAY_SIZE(early_log)) {
+		crt_early_log++;
 		kmemleak_disable();
 		return;
 	}
@@ -1882,7 +1883,7 @@ void __init kmemleak_init(void)
 	object_cache = KMEM_CACHE(kmemleak_object, SLAB_NOLEAKTRACE);
 	scan_area_cache = KMEM_CACHE(kmemleak_scan_area, SLAB_NOLEAKTRACE);
 
-	if (crt_early_log >= ARRAY_SIZE(early_log))
+	if (crt_early_log > ARRAY_SIZE(early_log))
 		pr_warning("Early log buffer exceeded (%d), please increase "
 			   "DEBUG_KMEMLEAK_EARLY_LOG_SIZE\n", crt_early_log);
 
diff --git a/mm/list_lru.c b/mm/list_lru.c
index 909eca2..e1da19f 100644
--- a/mm/list_lru.c
+++ b/mm/list_lru.c
@@ -99,8 +99,8 @@ bool list_lru_add(struct list_lru *lru, struct list_head *item)
 	struct list_lru_one *l;
 
 	spin_lock(&nlru->lock);
-	l = list_lru_from_kmem(nlru, item);
 	if (list_empty(item)) {
+		l = list_lru_from_kmem(nlru, item);
 		list_add_tail(item, &l->list);
 		l->nr_items++;
 		spin_unlock(&nlru->lock);
@@ -118,8 +118,8 @@ bool list_lru_del(struct list_lru *lru, struct list_head *item)
 	struct list_lru_one *l;
 
 	spin_lock(&nlru->lock);
-	l = list_lru_from_kmem(nlru, item);
 	if (!list_empty(item)) {
+		l = list_lru_from_kmem(nlru, item);
 		list_del_init(item);
 		l->nr_items--;
 		spin_unlock(&nlru->lock);
diff --git a/mm/madvise.c b/mm/madvise.c
index ce3a422..c889fcb 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -301,7 +301,7 @@ static long madvise_remove(struct vm_area_struct *vma,
 
 	*prev = NULL;	/* tell sys_madvise we drop mmap_sem */
 
-	if (vma->vm_flags & (VM_LOCKED | VM_HUGETLB))
+	if (vma->vm_flags & VM_LOCKED)
 		return -EINVAL;
 
 	f = vma->vm_file;
diff --git a/mm/memblock.c b/mm/memblock.c
index 95ce68c..1c7b647 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -91,7 +91,7 @@ static unsigned long __init_memblock memblock_addrs_overlap(phys_addr_t base1, p
 	return ((base1 < (base2 + size2)) && (base2 < (base1 + size1)));
 }
 
-static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
+bool __init_memblock memblock_overlaps_region(struct memblock_type *type,
 					phys_addr_t base, phys_addr_t size)
 {
 	unsigned long i;
@@ -103,7 +103,7 @@ static long __init_memblock memblock_overlaps_region(struct memblock_type *type,
 			break;
 	}
 
-	return (i < type->cnt) ? i : -1;
+	return i < type->cnt;
 }
 
 /*
@@ -569,6 +569,7 @@ repeat:
 #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, i++, base,
@@ -614,14 +615,14 @@ static int __init_memblock memblock_add_region(phys_addr_t base,
 						int nid,
 						unsigned long flags)
 {
-	struct memblock_type *_rgn = &memblock.memory;
+	struct memblock_type *type = &memblock.memory;
 
 	memblock_dbg("memblock_add: [%#016llx-%#016llx] flags %#02lx %pF\n",
 		     (unsigned long long)base,
 		     (unsigned long long)base + size - 1,
 		     flags, (void *)_RET_IP_);
 
-	return memblock_add_range(_rgn, base, size, nid, flags);
+	return memblock_add_range(type, base, size, nid, flags);
 }
 
 int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
@@ -761,7 +762,7 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
  *
  * This function isolates region [@base, @base + @size), and sets/clears flag
  *
- * Return 0 on succees, -errno on failure.
+ * 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)
@@ -788,7 +789,7 @@ static int __init_memblock memblock_setclr_flag(phys_addr_t base,
  * @base: the base phys addr of the region
  * @size: the size of the region
  *
- * Return 0 on succees, -errno on failure.
+ * Return 0 on success, -errno on failure.
  */
 int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
 {
@@ -800,7 +801,7 @@ int __init_memblock memblock_mark_hotplug(phys_addr_t base, phys_addr_t size)
  * @base: the base phys addr of the region
  * @size: the size of the region
  *
- * Return 0 on succees, -errno on failure.
+ * Return 0 on success, -errno on failure.
  */
 int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
 {
@@ -812,7 +813,7 @@ int __init_memblock memblock_clear_hotplug(phys_addr_t base, phys_addr_t size)
  * @base: the base phys addr of the region
  * @size: the size of the region
  *
- * Return 0 on succees, -errno on failure.
+ * Return 0 on success, -errno on failure.
  */
 int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
 {
@@ -834,10 +835,10 @@ void __init_memblock __next_reserved_mem_region(u64 *idx,
 					   phys_addr_t *out_start,
 					   phys_addr_t *out_end)
 {
-	struct memblock_type *rsv = &memblock.reserved;
+	struct memblock_type *type = &memblock.reserved;
 
-	if (*idx >= 0 && *idx < rsv->cnt) {
-		struct memblock_region *r = &rsv->regions[*idx];
+	if (*idx >= 0 && *idx < type->cnt) {
+		struct memblock_region *r = &type->regions[*idx];
 		phys_addr_t base = r->base;
 		phys_addr_t size = r->size;
 
@@ -975,7 +976,7 @@ void __init_memblock __next_mem_range(u64 *idx, int nid, ulong flags,
  * in type_b.
  *
  * @idx: pointer to u64 loop variable
- * @nid: nid: node selector, %NUMA_NO_NODE for all nodes
+ * @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
@@ -1565,12 +1566,12 @@ int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size
  * Check if the region [@base, @base+@size) intersects a reserved memory block.
  *
  * RETURNS:
- * 0 if false, non-zero if true
+ * True if they intersect, false if not.
  */
-int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
+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) >= 0;
+	return memblock_overlaps_region(&memblock.reserved, base, size);
 }
 
 void __init_memblock memblock_trim_memory(phys_addr_t align)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1af0575..1742a2d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -111,56 +111,10 @@ static const char * const mem_cgroup_lru_names[] = {
 	"unevictable",
 };
 
-/*
- * Per memcg event counter is incremented at every pagein/pageout. With THP,
- * it will be incremated by the number of pages. This counter is used for
- * for trigger some periodic events. This is straightforward and better
- * than using jiffies etc. to handle periodic memcg event.
- */
-enum mem_cgroup_events_target {
-	MEM_CGROUP_TARGET_THRESH,
-	MEM_CGROUP_TARGET_SOFTLIMIT,
-	MEM_CGROUP_TARGET_NUMAINFO,
-	MEM_CGROUP_NTARGETS,
-};
 #define THRESHOLDS_EVENTS_TARGET 128
 #define SOFTLIMIT_EVENTS_TARGET 1024
 #define NUMAINFO_EVENTS_TARGET	1024
 
-struct mem_cgroup_stat_cpu {
-	long count[MEM_CGROUP_STAT_NSTATS];
-	unsigned long events[MEMCG_NR_EVENTS];
-	unsigned long nr_page_events;
-	unsigned long targets[MEM_CGROUP_NTARGETS];
-};
-
-struct reclaim_iter {
-	struct mem_cgroup *position;
-	/* scan generation, increased every round-trip */
-	unsigned int generation;
-};
-
-/*
- * per-zone information in memory controller.
- */
-struct mem_cgroup_per_zone {
-	struct lruvec		lruvec;
-	unsigned long		lru_size[NR_LRU_LISTS];
-
-	struct reclaim_iter	iter[DEF_PRIORITY + 1];
-
-	struct rb_node		tree_node;	/* RB tree node */
-	unsigned long		usage_in_excess;/* Set to the value by which */
-						/* the soft limit is exceeded*/
-	bool			on_tree;
-	struct mem_cgroup	*memcg;		/* Back pointer, we cannot */
-						/* use container_of	   */
-};
-
-struct mem_cgroup_per_node {
-	struct mem_cgroup_per_zone zoneinfo[MAX_NR_ZONES];
-};
-
 /*
  * Cgroups above their limits are maintained in a RB-Tree, independent of
  * their hierarchy representation
@@ -181,32 +135,6 @@ struct mem_cgroup_tree {
 
 static struct mem_cgroup_tree soft_limit_tree __read_mostly;
 
-struct mem_cgroup_threshold {
-	struct eventfd_ctx *eventfd;
-	unsigned long threshold;
-};
-
-/* For threshold */
-struct mem_cgroup_threshold_ary {
-	/* An array index points to threshold just below or equal to usage. */
-	int current_threshold;
-	/* Size of entries[] */
-	unsigned int size;
-	/* Array of thresholds */
-	struct mem_cgroup_threshold entries[0];
-};
-
-struct mem_cgroup_thresholds {
-	/* Primary thresholds array */
-	struct mem_cgroup_threshold_ary *primary;
-	/*
-	 * Spare threshold array.
-	 * This is needed to make mem_cgroup_unregister_event() "never fail".
-	 * It must be able to store at least primary->size - 1 entries.
-	 */
-	struct mem_cgroup_threshold_ary *spare;
-};
-
 /* for OOM */
 struct mem_cgroup_eventfd_list {
 	struct list_head list;
@@ -256,113 +184,6 @@ struct mem_cgroup_event {
 static void mem_cgroup_threshold(struct mem_cgroup *memcg);
 static void mem_cgroup_oom_notify(struct mem_cgroup *memcg);
 
-/*
- * The memory controller data structure. The memory controller controls both
- * page cache and RSS per cgroup. We would eventually like to provide
- * statistics based on the statistics developed by Rik Van Riel for clock-pro,
- * to help the administrator determine what knobs to tune.
- */
-struct mem_cgroup {
-	struct cgroup_subsys_state css;
-
-	/* Accounted resources */
-	struct page_counter memory;
-	struct page_counter memsw;
-	struct page_counter kmem;
-
-	/* Normal memory consumption range */
-	unsigned long low;
-	unsigned long high;
-
-	unsigned long soft_limit;
-
-	/* vmpressure notifications */
-	struct vmpressure vmpressure;
-
-	/* css_online() has been completed */
-	int initialized;
-
-	/*
-	 * Should the accounting and control be hierarchical, per subtree?
-	 */
-	bool use_hierarchy;
-
-	/* protected by memcg_oom_lock */
-	bool		oom_lock;
-	int		under_oom;
-
-	int	swappiness;
-	/* OOM-Killer disable */
-	int		oom_kill_disable;
-
-	/* protect arrays of thresholds */
-	struct mutex thresholds_lock;
-
-	/* thresholds for memory usage. RCU-protected */
-	struct mem_cgroup_thresholds thresholds;
-
-	/* thresholds for mem+swap usage. RCU-protected */
-	struct mem_cgroup_thresholds memsw_thresholds;
-
-	/* For oom notifier event fd */
-	struct list_head oom_notify;
-
-	/*
-	 * Should we move charges of a task when a task is moved into this
-	 * mem_cgroup ? And what type of charges should we move ?
-	 */
-	unsigned long move_charge_at_immigrate;
-	/*
-	 * set > 0 if pages under this cgroup are moving to other cgroup.
-	 */
-	atomic_t		moving_account;
-	/* taken only while moving_account > 0 */
-	spinlock_t		move_lock;
-	struct task_struct	*move_lock_task;
-	unsigned long		move_lock_flags;
-	/*
-	 * percpu counter.
-	 */
-	struct mem_cgroup_stat_cpu __percpu *stat;
-	spinlock_t pcp_counter_lock;
-
-#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_INET)
-	struct cg_proto tcp_mem;
-#endif
-#if defined(CONFIG_MEMCG_KMEM)
-        /* Index in the kmem_cache->memcg_params.memcg_caches array */
-	int kmemcg_id;
-	bool kmem_acct_activated;
-	bool kmem_acct_active;
-#endif
-
-	int last_scanned_node;
-#if MAX_NUMNODES > 1
-	nodemask_t	scan_nodes;
-	atomic_t	numainfo_events;
-	atomic_t	numainfo_updating;
-#endif
-
-#ifdef CONFIG_CGROUP_WRITEBACK
-	struct list_head cgwb_list;
-	struct wb_domain cgwb_domain;
-#endif
-
-	/* List of events which userspace want to receive */
-	struct list_head event_list;
-	spinlock_t event_list_lock;
-
-	struct mem_cgroup_per_node *nodeinfo[0];
-	/* WARNING: nodeinfo must be the last member here */
-};
-
-#ifdef CONFIG_MEMCG_KMEM
-bool memcg_kmem_is_active(struct mem_cgroup *memcg)
-{
-	return memcg->kmem_acct_active;
-}
-#endif
-
 /* Stuffs for move charges at task migration. */
 /*
  * Types of charges to be moved.
@@ -423,11 +244,6 @@ enum res_type {
  */
 static DEFINE_MUTEX(memcg_create_mutex);
 
-struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *s)
-{
-	return s ? container_of(s, struct mem_cgroup, css) : NULL;
-}
-
 /* Some nice accessors for the vmpressure. */
 struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg)
 {
@@ -499,8 +315,7 @@ void sock_update_memcg(struct sock *sk)
 		rcu_read_lock();
 		memcg = mem_cgroup_from_task(current);
 		cg_proto = sk->sk_prot->proto_cgroup(memcg);
-		if (!mem_cgroup_is_root(memcg) &&
-		    memcg_proto_active(cg_proto) &&
+		if (cg_proto && test_bit(MEMCG_SOCK_ACTIVE, &cg_proto->flags) &&
 		    css_tryget_online(&memcg->css)) {
 			sk->sk_cgrp = cg_proto;
 		}
@@ -593,11 +408,6 @@ mem_cgroup_zone_zoneinfo(struct mem_cgroup *memcg, struct zone *zone)
 	return &memcg->nodeinfo[nid]->zoneinfo[zid];
 }
 
-struct cgroup_subsys_state *mem_cgroup_css(struct mem_cgroup *memcg)
-{
-	return &memcg->css;
-}
-
 /**
  * mem_cgroup_css_from_page - css of the memcg associated with a page
  * @page: page of interest
@@ -876,14 +686,6 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
 	__this_cpu_add(memcg->stat->nr_page_events, nr_pages);
 }
 
-unsigned long mem_cgroup_get_lru_size(struct lruvec *lruvec, enum lru_list lru)
-{
-	struct mem_cgroup_per_zone *mz;
-
-	mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec);
-	return mz->lru_size[lru];
-}
-
 static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
 						  int nid,
 						  unsigned int lru_mask)
@@ -986,6 +788,7 @@ struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p)
 
 	return mem_cgroup_from_css(task_css(p, memory_cgrp_id));
 }
+EXPORT_SYMBOL(mem_cgroup_from_task);
 
 static struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm)
 {
@@ -1031,7 +834,7 @@ struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *root,
 				   struct mem_cgroup *prev,
 				   struct mem_cgroup_reclaim_cookie *reclaim)
 {
-	struct reclaim_iter *uninitialized_var(iter);
+	struct mem_cgroup_reclaim_iter *uninitialized_var(iter);
 	struct cgroup_subsys_state *css = NULL;
 	struct mem_cgroup *memcg = NULL;
 	struct mem_cgroup *pos = NULL;
@@ -1173,30 +976,6 @@ void mem_cgroup_iter_break(struct mem_cgroup *root,
 	     iter != NULL;				\
 	     iter = mem_cgroup_iter(NULL, iter, NULL))
 
-void __mem_cgroup_count_vm_event(struct mm_struct *mm, enum vm_event_item idx)
-{
-	struct mem_cgroup *memcg;
-
-	rcu_read_lock();
-	memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
-	if (unlikely(!memcg))
-		goto out;
-
-	switch (idx) {
-	case PGFAULT:
-		this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGFAULT]);
-		break;
-	case PGMAJFAULT:
-		this_cpu_inc(memcg->stat->events[MEM_CGROUP_EVENTS_PGMAJFAULT]);
-		break;
-	default:
-		BUG();
-	}
-out:
-	rcu_read_unlock();
-}
-EXPORT_SYMBOL(__mem_cgroup_count_vm_event);
-
 /**
  * mem_cgroup_zone_lruvec - get the lru list vector for a zone and memcg
  * @zone: zone of the wanted lruvec
@@ -1295,15 +1074,6 @@ void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
 	VM_BUG_ON((long)(*lru_size) < 0);
 }
 
-bool mem_cgroup_is_descendant(struct mem_cgroup *memcg, struct mem_cgroup *root)
-{
-	if (root == memcg)
-		return true;
-	if (!root->use_hierarchy)
-		return false;
-	return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup);
-}
-
 bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg)
 {
 	struct mem_cgroup *task_memcg;
@@ -1330,39 +1100,6 @@ bool task_in_mem_cgroup(struct task_struct *task, struct mem_cgroup *memcg)
 	return ret;
 }
 
-int mem_cgroup_inactive_anon_is_low(struct lruvec *lruvec)
-{
-	unsigned long inactive_ratio;
-	unsigned long inactive;
-	unsigned long active;
-	unsigned long gb;
-
-	inactive = mem_cgroup_get_lru_size(lruvec, LRU_INACTIVE_ANON);
-	active = mem_cgroup_get_lru_size(lruvec, LRU_ACTIVE_ANON);
-
-	gb = (inactive + active) >> (30 - PAGE_SHIFT);
-	if (gb)
-		inactive_ratio = int_sqrt(10 * gb);
-	else
-		inactive_ratio = 1;
-
-	return inactive * inactive_ratio < active;
-}
-
-bool mem_cgroup_lruvec_online(struct lruvec *lruvec)
-{
-	struct mem_cgroup_per_zone *mz;
-	struct mem_cgroup *memcg;
-
-	if (mem_cgroup_disabled())
-		return true;
-
-	mz = container_of(lruvec, struct mem_cgroup_per_zone, lruvec);
-	memcg = mz->memcg;
-
-	return !!(memcg->css.flags & CSS_ONLINE);
-}
-
 #define mem_cgroup_from_counter(counter, member)	\
 	container_of(counter, struct mem_cgroup, member)
 
@@ -1394,15 +1131,6 @@ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg)
 	return margin;
 }
 
-int mem_cgroup_swappiness(struct mem_cgroup *memcg)
-{
-	/* root ? */
-	if (mem_cgroup_disabled() || !memcg->css.parent)
-		return vm_swappiness;
-
-	return memcg->swappiness;
-}
-
 /*
  * A routine for checking "mem" is under move_account() or not.
  *
@@ -1545,6 +1273,12 @@ static unsigned long mem_cgroup_get_limit(struct mem_cgroup *memcg)
 static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
 				     int order)
 {
+	struct oom_control oc = {
+		.zonelist = NULL,
+		.nodemask = NULL,
+		.gfp_mask = gfp_mask,
+		.order = order,
+	};
 	struct mem_cgroup *iter;
 	unsigned long chosen_points = 0;
 	unsigned long totalpages;
@@ -1563,7 +1297,7 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
 		goto unlock;
 	}
 
-	check_panic_on_oom(CONSTRAINT_MEMCG, gfp_mask, order, NULL, memcg);
+	check_panic_on_oom(&oc, CONSTRAINT_MEMCG, memcg);
 	totalpages = mem_cgroup_get_limit(memcg) ? : 1;
 	for_each_mem_cgroup_tree(iter, memcg) {
 		struct css_task_iter it;
@@ -1571,8 +1305,7 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
 
 		css_task_iter_start(&iter->css, &it);
 		while ((task = css_task_iter_next(&it))) {
-			switch (oom_scan_process_thread(task, totalpages, NULL,
-							false)) {
+			switch (oom_scan_process_thread(&oc, task, totalpages)) {
 			case OOM_SCAN_SELECT:
 				if (chosen)
 					put_task_struct(chosen);
@@ -1610,8 +1343,8 @@ static void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
 
 	if (chosen) {
 		points = chosen_points * 1000 / totalpages;
-		oom_kill_process(chosen, gfp_mask, order, points, totalpages,
-				 memcg, NULL, "Memory cgroup out of memory");
+		oom_kill_process(&oc, chosen, points, totalpages, memcg,
+				 "Memory cgroup out of memory");
 	}
 unlock:
 	mutex_unlock(&oom_lock);
@@ -2062,23 +1795,6 @@ void mem_cgroup_end_page_stat(struct mem_cgroup *memcg)
 }
 EXPORT_SYMBOL(mem_cgroup_end_page_stat);
 
-/**
- * mem_cgroup_update_page_stat - update page state statistics
- * @memcg: memcg to account against
- * @idx: page state item to account
- * @val: number of pages (positive or negative)
- *
- * See mem_cgroup_begin_page_stat() for locking requirements.
- */
-void mem_cgroup_update_page_stat(struct mem_cgroup *memcg,
-				 enum mem_cgroup_stat_index idx, int val)
-{
-	VM_BUG_ON(!rcu_read_lock_held());
-
-	if (memcg)
-		this_cpu_add(memcg->stat->count[idx], val);
-}
-
 /*
  * size of first charge trial. "32" comes from vmscan.c's magic value.
  * TODO: maybe necessary to use big numbers in big irons.
@@ -2504,16 +2220,6 @@ void memcg_uncharge_kmem(struct mem_cgroup *memcg, unsigned long nr_pages)
 	css_put_many(&memcg->css, nr_pages);
 }
 
-/*
- * helper for acessing a memcg's index. It will be used as an index in the
- * child cache array in kmem_cache, and also to derive its name. This function
- * will return -1 when this is not a kmem-limited memcg.
- */
-int memcg_cache_id(struct mem_cgroup *memcg)
-{
-	return memcg ? memcg->kmemcg_id : -1;
-}
-
 static int memcg_alloc_cache_id(void)
 {
 	int id, size;
@@ -5127,10 +4833,12 @@ static void mem_cgroup_clear_mc(void)
 static int mem_cgroup_can_attach(struct cgroup_subsys_state *css,
 				 struct cgroup_taskset *tset)
 {
-	struct task_struct *p = cgroup_taskset_first(tset);
-	int ret = 0;
 	struct mem_cgroup *memcg = mem_cgroup_from_css(css);
+	struct mem_cgroup *from;
+	struct task_struct *p;
+	struct mm_struct *mm;
 	unsigned long move_flags;
+	int ret = 0;
 
 	/*
 	 * We are now commited to this value whatever it is. Changes in this
@@ -5138,36 +4846,37 @@ static int mem_cgroup_can_attach(struct cgroup_subsys_state *css,
 	 * So we need to save it, and keep it going.
 	 */
 	move_flags = READ_ONCE(memcg->move_charge_at_immigrate);
-	if (move_flags) {
-		struct mm_struct *mm;
-		struct mem_cgroup *from = mem_cgroup_from_task(p);
+	if (!move_flags)
+		return 0;
 
-		VM_BUG_ON(from == memcg);
+	p = cgroup_taskset_first(tset);
+	from = mem_cgroup_from_task(p);
 
-		mm = get_task_mm(p);
-		if (!mm)
-			return 0;
-		/* We move charges only when we move a owner of the mm */
-		if (mm->owner == p) {
-			VM_BUG_ON(mc.from);
-			VM_BUG_ON(mc.to);
-			VM_BUG_ON(mc.precharge);
-			VM_BUG_ON(mc.moved_charge);
-			VM_BUG_ON(mc.moved_swap);
-
-			spin_lock(&mc.lock);
-			mc.from = from;
-			mc.to = memcg;
-			mc.flags = move_flags;
-			spin_unlock(&mc.lock);
-			/* We set mc.moving_task later */
-
-			ret = mem_cgroup_precharge_mc(mm);
-			if (ret)
-				mem_cgroup_clear_mc();
-		}
-		mmput(mm);
+	VM_BUG_ON(from == memcg);
+
+	mm = get_task_mm(p);
+	if (!mm)
+		return 0;
+	/* We move charges only when we move a owner of the mm */
+	if (mm->owner == p) {
+		VM_BUG_ON(mc.from);
+		VM_BUG_ON(mc.to);
+		VM_BUG_ON(mc.precharge);
+		VM_BUG_ON(mc.moved_charge);
+		VM_BUG_ON(mc.moved_swap);
+
+		spin_lock(&mc.lock);
+		mc.from = from;
+		mc.to = memcg;
+		mc.flags = move_flags;
+		spin_unlock(&mc.lock);
+		/* We set mc.moving_task later */
+
+		ret = mem_cgroup_precharge_mc(mm);
+		if (ret)
+			mem_cgroup_clear_mc();
 	}
+	mmput(mm);
 	return ret;
 }
 
@@ -5521,19 +5230,6 @@ struct cgroup_subsys memory_cgrp_subsys = {
 };
 
 /**
- * mem_cgroup_events - count memory events against a cgroup
- * @memcg: the memory cgroup
- * @idx: the event index
- * @nr: the number of events to account for
- */
-void mem_cgroup_events(struct mem_cgroup *memcg,
-		       enum mem_cgroup_events_index idx,
-		       unsigned int nr)
-{
-	this_cpu_add(memcg->stat->events[idx], nr);
-}
-
-/**
  * mem_cgroup_low - check if memory consumption is below the normal range
  * @root: the highest ancestor to consider
  * @memcg: the memory cgroup to check
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 1f4446a9..eeda648 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -146,7 +146,7 @@ static int hwpoison_filter_task(struct page *p)
 	if (!mem)
 		return -EINVAL;
 
-	css = mem_cgroup_css(mem);
+	css = &mem->css;
 	ino = cgroup_ino(css->cgroup);
 	css_put(css);
 
@@ -934,6 +934,27 @@ int get_hwpoison_page(struct page *page)
 }
 EXPORT_SYMBOL_GPL(get_hwpoison_page);
 
+/**
+ * put_hwpoison_page() - Put refcount for memory error handling:
+ * @page:	raw error page (hit by memory error)
+ */
+void put_hwpoison_page(struct page *page)
+{
+	struct page *head = compound_head(page);
+
+	if (PageHuge(head)) {
+		put_page(head);
+		return;
+	}
+
+	if (PageTransHuge(head))
+		if (page != head)
+			put_page(head);
+
+	put_page(page);
+}
+EXPORT_SYMBOL_GPL(put_hwpoison_page);
+
 /*
  * Do all that is necessary to remove user space mappings. Unmap
  * the pages and send SIGBUS to the processes if the data was dirty.
@@ -1100,7 +1121,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 		nr_pages = 1 << compound_order(hpage);
 	else /* normal page or thp */
 		nr_pages = 1;
-	atomic_long_add(nr_pages, &num_poisoned_pages);
+	num_poisoned_pages_add(nr_pages);
 
 	/*
 	 * We need/can do nothing about count=0 pages.
@@ -1128,7 +1149,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 			if (PageHWPoison(hpage)) {
 				if ((hwpoison_filter(p) && TestClearPageHWPoison(p))
 				    || (p != hpage && TestSetPageHWPoison(hpage))) {
-					atomic_long_sub(nr_pages, &num_poisoned_pages);
+					num_poisoned_pages_sub(nr_pages);
 					unlock_page(hpage);
 					return 0;
 				}
@@ -1152,10 +1173,8 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 			else
 				pr_err("MCE: %#lx: thp split failed\n", pfn);
 			if (TestClearPageHWPoison(p))
-				atomic_long_sub(nr_pages, &num_poisoned_pages);
-			put_page(p);
-			if (p != hpage)
-				put_page(hpage);
+				num_poisoned_pages_sub(nr_pages);
+			put_hwpoison_page(p);
 			return -EBUSY;
 		}
 		VM_BUG_ON_PAGE(!page_count(p), p);
@@ -1214,16 +1233,16 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 	 */
 	if (!PageHWPoison(p)) {
 		printk(KERN_ERR "MCE %#lx: just unpoisoned\n", pfn);
-		atomic_long_sub(nr_pages, &num_poisoned_pages);
+		num_poisoned_pages_sub(nr_pages);
 		unlock_page(hpage);
-		put_page(hpage);
+		put_hwpoison_page(hpage);
 		return 0;
 	}
 	if (hwpoison_filter(p)) {
 		if (TestClearPageHWPoison(p))
-			atomic_long_sub(nr_pages, &num_poisoned_pages);
+			num_poisoned_pages_sub(nr_pages);
 		unlock_page(hpage);
-		put_page(hpage);
+		put_hwpoison_page(hpage);
 		return 0;
 	}
 
@@ -1237,7 +1256,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 	if (PageHuge(p) && PageTail(p) && TestSetPageHWPoison(hpage)) {
 		action_result(pfn, MF_MSG_POISONED_HUGE, MF_IGNORED);
 		unlock_page(hpage);
-		put_page(hpage);
+		put_hwpoison_page(hpage);
 		return 0;
 	}
 	/*
@@ -1426,6 +1445,22 @@ int unpoison_memory(unsigned long pfn)
 		return 0;
 	}
 
+	if (page_count(page) > 1) {
+		pr_info("MCE: Someone grabs the hwpoison page %#lx\n", pfn);
+		return 0;
+	}
+
+	if (page_mapped(page)) {
+		pr_info("MCE: Someone maps the hwpoison page %#lx\n", pfn);
+		return 0;
+	}
+
+	if (page_mapping(page)) {
+		pr_info("MCE: the hwpoison page has non-NULL mapping %#lx\n",
+			pfn);
+		return 0;
+	}
+
 	/*
 	 * unpoison_memory() can encounter thp only when the thp is being
 	 * worked by memory_failure() and the page lock is not held yet.
@@ -1450,7 +1485,7 @@ int unpoison_memory(unsigned long pfn)
 			return 0;
 		}
 		if (TestClearPageHWPoison(p))
-			atomic_long_dec(&num_poisoned_pages);
+			num_poisoned_pages_dec();
 		pr_info("MCE: Software-unpoisoned free page %#lx\n", pfn);
 		return 0;
 	}
@@ -1464,16 +1499,16 @@ int unpoison_memory(unsigned long pfn)
 	 */
 	if (TestClearPageHWPoison(page)) {
 		pr_info("MCE: Software-unpoisoned page %#lx\n", pfn);
-		atomic_long_sub(nr_pages, &num_poisoned_pages);
+		num_poisoned_pages_sub(nr_pages);
 		freeit = 1;
 		if (PageHuge(page))
 			clear_page_hwpoison_huge_page(page);
 	}
 	unlock_page(page);
 
-	put_page(page);
+	put_hwpoison_page(page);
 	if (freeit && !(pfn == my_zero_pfn(0) && page_count(p) == 1))
-		put_page(page);
+		put_hwpoison_page(page);
 
 	return 0;
 }
@@ -1486,7 +1521,7 @@ static struct page *new_page(struct page *p, unsigned long private, int **x)
 		return alloc_huge_page_node(page_hstate(compound_head(p)),
 						   nid);
 	else
-		return alloc_pages_exact_node(nid, GFP_HIGHUSER_MOVABLE, 0);
+		return __alloc_pages_node(nid, GFP_HIGHUSER_MOVABLE, 0);
 }
 
 /*
@@ -1533,7 +1568,7 @@ static int get_any_page(struct page *page, unsigned long pfn, int flags)
 		/*
 		 * Try to free it.
 		 */
-		put_page(page);
+		put_hwpoison_page(page);
 		shake_page(page, 1);
 
 		/*
@@ -1542,7 +1577,7 @@ static int get_any_page(struct page *page, unsigned long pfn, int flags)
 		ret = __get_any_page(page, pfn, 0);
 		if (!PageLRU(page)) {
 			/* Drop page reference which is from __get_any_page() */
-			put_page(page);
+			put_hwpoison_page(page);
 			pr_info("soft_offline: %#lx: unknown non LRU page type %lx\n",
 				pfn, page->flags);
 			return -EIO;
@@ -1565,7 +1600,7 @@ static int soft_offline_huge_page(struct page *page, int flags)
 	lock_page(hpage);
 	if (PageHWPoison(hpage)) {
 		unlock_page(hpage);
-		put_page(hpage);
+		put_hwpoison_page(hpage);
 		pr_info("soft offline: %#lx hugepage already poisoned\n", pfn);
 		return -EBUSY;
 	}
@@ -1576,7 +1611,7 @@ static int soft_offline_huge_page(struct page *page, int flags)
 	 * get_any_page() and isolate_huge_page() takes a refcount each,
 	 * so need to drop one here.
 	 */
-	put_page(hpage);
+	put_hwpoison_page(hpage);
 	if (!ret) {
 		pr_info("soft offline: %#lx hugepage failed to isolate\n", pfn);
 		return -EBUSY;
@@ -1600,11 +1635,10 @@ static int soft_offline_huge_page(struct page *page, int flags)
 		if (PageHuge(page)) {
 			set_page_hwpoison_huge_page(hpage);
 			dequeue_hwpoisoned_huge_page(hpage);
-			atomic_long_add(1 << compound_order(hpage),
-					&num_poisoned_pages);
+			num_poisoned_pages_add(1 << compound_order(hpage));
 		} else {
 			SetPageHWPoison(page);
-			atomic_long_inc(&num_poisoned_pages);
+			num_poisoned_pages_inc();
 		}
 	}
 	return ret;
@@ -1625,7 +1659,7 @@ static int __soft_offline_page(struct page *page, int flags)
 	wait_on_page_writeback(page);
 	if (PageHWPoison(page)) {
 		unlock_page(page);
-		put_page(page);
+		put_hwpoison_page(page);
 		pr_info("soft offline: %#lx page already poisoned\n", pfn);
 		return -EBUSY;
 	}
@@ -1640,10 +1674,10 @@ static int __soft_offline_page(struct page *page, int flags)
 	 * would need to fix isolation locking first.
 	 */
 	if (ret == 1) {
-		put_page(page);
+		put_hwpoison_page(page);
 		pr_info("soft_offline: %#lx: invalidated\n", pfn);
 		SetPageHWPoison(page);
-		atomic_long_inc(&num_poisoned_pages);
+		num_poisoned_pages_inc();
 		return 0;
 	}
 
@@ -1657,14 +1691,12 @@ static int __soft_offline_page(struct page *page, int flags)
 	 * Drop page reference which is came from get_any_page()
 	 * successful isolate_lru_page() already took another one.
 	 */
-	put_page(page);
+	put_hwpoison_page(page);
 	if (!ret) {
 		LIST_HEAD(pagelist);
 		inc_zone_page_state(page, NR_ISOLATED_ANON +
 					page_is_file_cache(page));
 		list_add(&page->lru, &pagelist);
-		if (!TestSetPageHWPoison(page))
-			atomic_long_inc(&num_poisoned_pages);
 		ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
 					MIGRATE_SYNC, MR_MEMORY_FAILURE);
 		if (ret) {
@@ -1679,8 +1711,6 @@ static int __soft_offline_page(struct page *page, int flags)
 				pfn, ret, page->flags);
 			if (ret > 0)
 				ret = -EIO;
-			if (TestClearPageHWPoison(page))
-				atomic_long_dec(&num_poisoned_pages);
 		}
 	} else {
 		pr_info("soft offline: %#lx: isolation failed: %d, page count %d, type %lx\n",
@@ -1719,12 +1749,16 @@ int soft_offline_page(struct page *page, int flags)
 
 	if (PageHWPoison(page)) {
 		pr_info("soft offline: %#lx page already poisoned\n", pfn);
+		if (flags & MF_COUNT_INCREASED)
+			put_hwpoison_page(page);
 		return -EBUSY;
 	}
 	if (!PageHuge(page) && PageTransHuge(hpage)) {
 		if (PageAnon(hpage) && unlikely(split_huge_page(hpage))) {
 			pr_info("soft offline: %#lx: failed to split THP\n",
 				pfn);
+			if (flags & MF_COUNT_INCREASED)
+				put_hwpoison_page(page);
 			return -EBUSY;
 		}
 	}
@@ -1742,11 +1776,10 @@ int soft_offline_page(struct page *page, int flags)
 		if (PageHuge(page)) {
 			set_page_hwpoison_huge_page(hpage);
 			if (!dequeue_hwpoisoned_huge_page(hpage))
-				atomic_long_add(1 << compound_order(hpage),
-					&num_poisoned_pages);
+				num_poisoned_pages_add(1 << compound_order(hpage));
 		} else {
 			if (!TestSetPageHWPoison(page))
-				atomic_long_inc(&num_poisoned_pages);
+				num_poisoned_pages_inc();
 		}
 	}
 	return ret;
diff --git a/mm/memory.c b/mm/memory.c
index bb04d8f..6cd0b21 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2426,8 +2426,6 @@ void unmap_mapping_range(struct address_space *mapping,
 	if (details.last_index < details.first_index)
 		details.last_index = ULONG_MAX;
 
-
-	/* DAX uses i_mmap_lock to serialise file truncate vs page fault */
 	i_mmap_lock_write(mapping);
 	if (unlikely(!RB_EMPTY_ROOT(&mapping->i_mmap)))
 		unmap_mapping_range_tree(&mapping->i_mmap, &details);
@@ -3015,9 +3013,9 @@ static int do_cow_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 		} else {
 			/*
 			 * The fault handler has no page to lock, so it holds
-			 * i_mmap_lock for read to protect against truncate.
+			 * i_mmap_lock for write to protect against truncate.
 			 */
-			i_mmap_unlock_read(vma->vm_file->f_mapping);
+			i_mmap_unlock_write(vma->vm_file->f_mapping);
 		}
 		goto uncharge_out;
 	}
@@ -3031,9 +3029,9 @@ static int do_cow_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 	} else {
 		/*
 		 * The fault handler has no page to lock, so it holds
-		 * i_mmap_lock for read to protect against truncate.
+		 * i_mmap_lock for write to protect against truncate.
 		 */
-		i_mmap_unlock_read(vma->vm_file->f_mapping);
+		i_mmap_unlock_write(vma->vm_file->f_mapping);
 	}
 	return ret;
 uncharge_out:
@@ -3232,6 +3230,27 @@ out:
 	return 0;
 }
 
+static int create_huge_pmd(struct mm_struct *mm, struct vm_area_struct *vma,
+			unsigned long address, pmd_t *pmd, unsigned int flags)
+{
+	if (!vma->vm_ops)
+		return do_huge_pmd_anonymous_page(mm, vma, address, pmd, flags);
+	if (vma->vm_ops->pmd_fault)
+		return vma->vm_ops->pmd_fault(vma, address, pmd, flags);
+	return VM_FAULT_FALLBACK;
+}
+
+static int wp_huge_pmd(struct mm_struct *mm, struct vm_area_struct *vma,
+			unsigned long address, pmd_t *pmd, pmd_t orig_pmd,
+			unsigned int flags)
+{
+	if (!vma->vm_ops)
+		return do_huge_pmd_wp_page(mm, vma, address, pmd, orig_pmd);
+	if (vma->vm_ops->pmd_fault)
+		return vma->vm_ops->pmd_fault(vma, address, pmd, flags);
+	return VM_FAULT_FALLBACK;
+}
+
 /*
  * These routines also need to handle stuff like marking pages dirty
  * and/or accessed for architectures that don't do it in hardware (most
@@ -3267,12 +3286,12 @@ static int handle_pte_fault(struct mm_struct *mm,
 	barrier();
 	if (!pte_present(entry)) {
 		if (pte_none(entry)) {
-			if (vma->vm_ops)
+			if (vma_is_anonymous(vma))
+				return do_anonymous_page(mm, vma, address,
+							 pte, pmd, flags);
+			else
 				return do_fault(mm, vma, address, pte, pmd,
 						flags, entry);
-
-			return do_anonymous_page(mm, vma, address, pte, pmd,
-					flags);
 		}
 		return do_swap_page(mm, vma, address,
 					pte, pmd, flags, entry);
@@ -3334,10 +3353,7 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 	if (!pmd)
 		return VM_FAULT_OOM;
 	if (pmd_none(*pmd) && transparent_hugepage_enabled(vma)) {
-		int ret = VM_FAULT_FALLBACK;
-		if (!vma->vm_ops)
-			ret = do_huge_pmd_anonymous_page(mm, vma, address,
-					pmd, flags);
+		int ret = create_huge_pmd(mm, vma, address, pmd, flags);
 		if (!(ret & VM_FAULT_FALLBACK))
 			return ret;
 	} else {
@@ -3361,8 +3377,8 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 							     orig_pmd, pmd);
 
 			if (dirty && !pmd_write(orig_pmd)) {
-				ret = do_huge_pmd_wp_page(mm, vma, address, pmd,
-							  orig_pmd);
+				ret = wp_huge_pmd(mm, vma, address, pmd,
+							orig_pmd, flags);
 				if (!(ret & VM_FAULT_FALLBACK))
 					return ret;
 			} else {
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index a7f1e0d..87a1779 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -608,9 +608,6 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end,
 
 	qp->prev = vma;
 
-	if (vma->vm_flags & VM_PFNMAP)
-		return 1;
-
 	if (flags & MPOL_MF_LAZY) {
 		/* Similar to task_numa_work, skip inaccessible VMAs */
 		if (vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))
@@ -945,7 +942,7 @@ static struct page *new_node_page(struct page *page, unsigned long node, int **x
 		return alloc_huge_page_node(page_hstate(compound_head(page)),
 					node);
 	else
-		return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE |
+		return __alloc_pages_node(node, GFP_HIGHUSER_MOVABLE |
 						    __GFP_THISNODE, 0);
 }
 
@@ -2001,7 +1998,7 @@ retry_cpuset:
 		nmask = policy_nodemask(gfp, pol);
 		if (!nmask || node_isset(hpage_node, *nmask)) {
 			mpol_cond_put(pol);
-			page = alloc_pages_exact_node(hpage_node,
+			page = __alloc_pages_node(hpage_node,
 						gfp | __GFP_THISNODE, order);
 			goto out;
 		}
diff --git a/mm/mempool.c b/mm/mempool.c
index 2cc08de..4c533bc 100644
--- a/mm/mempool.c
+++ b/mm/mempool.c
@@ -150,6 +150,9 @@ static void *remove_element(mempool_t *pool)
  */
 void mempool_destroy(mempool_t *pool)
 {
+	if (unlikely(!pool))
+		return;
+
 	while (pool->curr_nr) {
 		void *element = remove_element(pool);
 		pool->free(element, pool->pool_data);
diff --git a/mm/memtest.c b/mm/memtest.c
index 0a1cc13..8eaa4c3 100644
--- a/mm/memtest.c
+++ b/mm/memtest.c
@@ -1,11 +1,6 @@
 #include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
 #include <linux/types.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
 #include <linux/init.h>
-#include <linux/pfn.h>
 #include <linux/memblock.h>
 
 static u64 patterns[] __initdata = {
@@ -31,10 +26,8 @@ static u64 patterns[] __initdata = {
 
 static void __init reserve_bad_mem(u64 pattern, phys_addr_t start_bad, phys_addr_t end_bad)
 {
-	printk(KERN_INFO "  %016llx bad mem addr %010llx - %010llx reserved\n",
-	       (unsigned long long) pattern,
-	       (unsigned long long) start_bad,
-	       (unsigned long long) end_bad);
+	pr_info("  %016llx bad mem addr %pa - %pa reserved\n",
+		cpu_to_be64(pattern), &start_bad, &end_bad);
 	memblock_reserve(start_bad, end_bad - start_bad);
 }
 
@@ -79,26 +72,26 @@ static void __init do_one_pass(u64 pattern, phys_addr_t start, phys_addr_t end)
 		this_start = clamp(this_start, start, end);
 		this_end = clamp(this_end, start, end);
 		if (this_start < this_end) {
-			printk(KERN_INFO "  %010llx - %010llx pattern %016llx\n",
-			       (unsigned long long)this_start,
-			       (unsigned long long)this_end,
-			       (unsigned long long)cpu_to_be64(pattern));
+			pr_info("  %pa - %pa pattern %016llx\n",
+				&this_start, &this_end, cpu_to_be64(pattern));
 			memtest(pattern, this_start, this_end - this_start);
 		}
 	}
 }
 
 /* default is disabled */
-static int memtest_pattern __initdata;
+static unsigned int memtest_pattern __initdata;
 
 static int __init parse_memtest(char *arg)
 {
+	int ret = 0;
+
 	if (arg)
-		memtest_pattern = simple_strtoul(arg, NULL, 0);
+		ret = kstrtouint(arg, 0, &memtest_pattern);
 	else
 		memtest_pattern = ARRAY_SIZE(patterns);
 
-	return 0;
+	return ret;
 }
 
 early_param("memtest", parse_memtest);
@@ -111,7 +104,7 @@ void __init early_memtest(phys_addr_t start, phys_addr_t end)
 	if (!memtest_pattern)
 		return;
 
-	printk(KERN_INFO "early_memtest: # of tests: %d\n", memtest_pattern);
+	pr_info("early_memtest: # of tests: %u\n", memtest_pattern);
 	for (i = memtest_pattern-1; i < UINT_MAX; --i) {
 		idx = i % ARRAY_SIZE(patterns);
 		do_one_pass(patterns[idx], start, end);
diff --git a/mm/migrate.c b/mm/migrate.c
index 5c08cab..02ce25d 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -880,8 +880,7 @@ static int __unmap_and_move(struct page *page, struct page *newpage,
 	/* Establish migration ptes or remove ptes */
 	if (page_mapped(page)) {
 		try_to_unmap(page,
-			TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS|
-			TTU_IGNORE_HWPOISON);
+			TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS);
 		page_was_mapped = 1;
 	}
 
@@ -952,9 +951,11 @@ out:
 		dec_zone_page_state(page, NR_ISOLATED_ANON +
 				page_is_file_cache(page));
 		/* Soft-offlined page shouldn't go through lru cache list */
-		if (reason == MR_MEMORY_FAILURE)
+		if (reason == MR_MEMORY_FAILURE) {
 			put_page(page);
-		else
+			if (!test_set_page_hwpoison(page))
+				num_poisoned_pages_inc();
+		} else
 			putback_lru_page(page);
 	}
 
@@ -1194,7 +1195,7 @@ static struct page *new_page_node(struct page *p, unsigned long private,
 		return alloc_huge_page_node(page_hstate(compound_head(p)),
 					pm->node);
 	else
-		return alloc_pages_exact_node(pm->node,
+		return __alloc_pages_node(pm->node,
 				GFP_HIGHUSER_MOVABLE | __GFP_THISNODE, 0);
 }
 
@@ -1554,7 +1555,7 @@ static struct page *alloc_misplaced_dst_page(struct page *page,
 	int nid = (int) data;
 	struct page *newpage;
 
-	newpage = alloc_pages_exact_node(nid,
+	newpage = __alloc_pages_node(nid,
 					 (GFP_HIGHUSER_MOVABLE |
 					  __GFP_THISNODE | __GFP_NOMEMALLOC |
 					  __GFP_NORETRY | __GFP_NOWARN) &
diff --git a/mm/mmap.c b/mm/mmap.c
index 82db4fc..b6be324 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2455,7 +2455,7 @@ static int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
 	      unsigned long addr, int new_below)
 {
 	struct vm_area_struct *new;
-	int err = -ENOMEM;
+	int err;
 
 	if (is_vm_hugetlb_page(vma) && (addr &
 					~(huge_page_mask(hstate_vma(vma)))))
@@ -2463,7 +2463,7 @@ static int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
 
 	new = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
 	if (!new)
-		goto out_err;
+		return -ENOMEM;
 
 	/* most fields are the same, copy all, and then fixup */
 	*new = *vma;
@@ -2511,7 +2511,6 @@ static int __split_vma(struct mm_struct *mm, struct vm_area_struct *vma,
 	mpol_put(vma_policy(new));
  out_free_vma:
 	kmem_cache_free(vm_area_cachep, new);
- out_err:
 	return err;
 }
 
@@ -2872,6 +2871,13 @@ int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
 	struct vm_area_struct *prev;
 	struct rb_node **rb_link, *rb_parent;
 
+	if (find_vma_links(mm, vma->vm_start, vma->vm_end,
+			   &prev, &rb_link, &rb_parent))
+		return -ENOMEM;
+	if ((vma->vm_flags & VM_ACCOUNT) &&
+	     security_vm_enough_memory_mm(mm, vma_pages(vma)))
+		return -ENOMEM;
+
 	/*
 	 * The vm_pgoff of a purely anonymous vma should be irrelevant
 	 * until its first write fault, when page's anon_vma and index
@@ -2884,16 +2890,10 @@ int insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
 	 * using the existing file pgoff checks and manipulations.
 	 * Similarly in do_mmap_pgoff and in do_brk.
 	 */
-	if (!vma->vm_file) {
+	if (vma_is_anonymous(vma)) {
 		BUG_ON(vma->anon_vma);
 		vma->vm_pgoff = vma->vm_start >> PAGE_SHIFT;
 	}
-	if (find_vma_links(mm, vma->vm_start, vma->vm_end,
-			   &prev, &rb_link, &rb_parent))
-		return -ENOMEM;
-	if ((vma->vm_flags & VM_ACCOUNT) &&
-	     security_vm_enough_memory_mm(mm, vma_pages(vma)))
-		return -ENOMEM;
 
 	vma_link(mm, vma, prev, rb_link, rb_parent);
 	return 0;
@@ -2918,7 +2918,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
 	 * If anonymous vma has not yet been faulted, update new pgoff
 	 * to match new location, to increase its chance of merging.
 	 */
-	if (unlikely(!vma->vm_file && !vma->anon_vma)) {
+	if (unlikely(vma_is_anonymous(vma) && !vma->anon_vma)) {
 		pgoff = addr >> PAGE_SHIFT;
 		faulted_in_anon_vma = false;
 	}
@@ -2952,30 +2952,31 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
 		*need_rmap_locks = (new_vma->vm_pgoff <= vma->vm_pgoff);
 	} else {
 		new_vma = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
-		if (new_vma) {
-			*new_vma = *vma;
-			new_vma->vm_start = addr;
-			new_vma->vm_end = addr + len;
-			new_vma->vm_pgoff = pgoff;
-			if (vma_dup_policy(vma, new_vma))
-				goto out_free_vma;
-			INIT_LIST_HEAD(&new_vma->anon_vma_chain);
-			if (anon_vma_clone(new_vma, vma))
-				goto out_free_mempol;
-			if (new_vma->vm_file)
-				get_file(new_vma->vm_file);
-			if (new_vma->vm_ops && new_vma->vm_ops->open)
-				new_vma->vm_ops->open(new_vma);
-			vma_link(mm, new_vma, prev, rb_link, rb_parent);
-			*need_rmap_locks = false;
-		}
+		if (!new_vma)
+			goto out;
+		*new_vma = *vma;
+		new_vma->vm_start = addr;
+		new_vma->vm_end = addr + len;
+		new_vma->vm_pgoff = pgoff;
+		if (vma_dup_policy(vma, new_vma))
+			goto out_free_vma;
+		INIT_LIST_HEAD(&new_vma->anon_vma_chain);
+		if (anon_vma_clone(new_vma, vma))
+			goto out_free_mempol;
+		if (new_vma->vm_file)
+			get_file(new_vma->vm_file);
+		if (new_vma->vm_ops && new_vma->vm_ops->open)
+			new_vma->vm_ops->open(new_vma);
+		vma_link(mm, new_vma, prev, rb_link, rb_parent);
+		*need_rmap_locks = false;
 	}
 	return new_vma;
 
- out_free_mempol:
+out_free_mempol:
 	mpol_put(vma_policy(new_vma));
- out_free_vma:
+out_free_vma:
 	kmem_cache_free(vm_area_cachep, new_vma);
+out:
 	return NULL;
 }
 
@@ -3027,21 +3028,13 @@ static int special_mapping_fault(struct vm_area_struct *vma,
 	pgoff_t pgoff;
 	struct page **pages;
 
-	/*
-	 * special mappings have no vm_file, and in that case, the mm
-	 * uses vm_pgoff internally. So we have to subtract it from here.
-	 * We are allowed to do this because we are the mm; do not copy
-	 * this code into drivers!
-	 */
-	pgoff = vmf->pgoff - vma->vm_pgoff;
-
 	if (vma->vm_ops == &legacy_special_mapping_vmops)
 		pages = vma->vm_private_data;
 	else
 		pages = ((struct vm_special_mapping *)vma->vm_private_data)->
 			pages;
 
-	for (; pgoff && *pages; ++pages)
+	for (pgoff = vmf->pgoff; pgoff && *pages; ++pages)
 		pgoff--;
 
 	if (*pages) {
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index dff991e..1ecc0bc 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -196,27 +196,26 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
  * Determine the type of allocation constraint.
  */
 #ifdef CONFIG_NUMA
-static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
-				gfp_t gfp_mask, nodemask_t *nodemask,
-				unsigned long *totalpages)
+static enum oom_constraint constrained_alloc(struct oom_control *oc,
+					     unsigned long *totalpages)
 {
 	struct zone *zone;
 	struct zoneref *z;
-	enum zone_type high_zoneidx = gfp_zone(gfp_mask);
+	enum zone_type high_zoneidx = gfp_zone(oc->gfp_mask);
 	bool cpuset_limited = false;
 	int nid;
 
 	/* Default to all available memory */
 	*totalpages = totalram_pages + total_swap_pages;
 
-	if (!zonelist)
+	if (!oc->zonelist)
 		return CONSTRAINT_NONE;
 	/*
 	 * Reach here only when __GFP_NOFAIL is used. So, we should avoid
 	 * to kill current.We have to random task kill in this case.
 	 * Hopefully, CONSTRAINT_THISNODE...but no way to handle it, now.
 	 */
-	if (gfp_mask & __GFP_THISNODE)
+	if (oc->gfp_mask & __GFP_THISNODE)
 		return CONSTRAINT_NONE;
 
 	/*
@@ -224,17 +223,18 @@ static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
 	 * the page allocator means a mempolicy is in effect.  Cpuset policy
 	 * is enforced in get_page_from_freelist().
 	 */
-	if (nodemask && !nodes_subset(node_states[N_MEMORY], *nodemask)) {
+	if (oc->nodemask &&
+	    !nodes_subset(node_states[N_MEMORY], *oc->nodemask)) {
 		*totalpages = total_swap_pages;
-		for_each_node_mask(nid, *nodemask)
+		for_each_node_mask(nid, *oc->nodemask)
 			*totalpages += node_spanned_pages(nid);
 		return CONSTRAINT_MEMORY_POLICY;
 	}
 
 	/* Check this allocation failure is caused by cpuset's wall function */
-	for_each_zone_zonelist_nodemask(zone, z, zonelist,
-			high_zoneidx, nodemask)
-		if (!cpuset_zone_allowed(zone, gfp_mask))
+	for_each_zone_zonelist_nodemask(zone, z, oc->zonelist,
+			high_zoneidx, oc->nodemask)
+		if (!cpuset_zone_allowed(zone, oc->gfp_mask))
 			cpuset_limited = true;
 
 	if (cpuset_limited) {
@@ -246,20 +246,18 @@ static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
 	return CONSTRAINT_NONE;
 }
 #else
-static enum oom_constraint constrained_alloc(struct zonelist *zonelist,
-				gfp_t gfp_mask, nodemask_t *nodemask,
-				unsigned long *totalpages)
+static enum oom_constraint constrained_alloc(struct oom_control *oc,
+					     unsigned long *totalpages)
 {
 	*totalpages = totalram_pages + total_swap_pages;
 	return CONSTRAINT_NONE;
 }
 #endif
 
-enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
-		unsigned long totalpages, const nodemask_t *nodemask,
-		bool force_kill)
+enum oom_scan_t oom_scan_process_thread(struct oom_control *oc,
+			struct task_struct *task, unsigned long totalpages)
 {
-	if (oom_unkillable_task(task, NULL, nodemask))
+	if (oom_unkillable_task(task, NULL, oc->nodemask))
 		return OOM_SCAN_CONTINUE;
 
 	/*
@@ -267,7 +265,7 @@ enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
 	 * Don't allow any other task to have access to the reserves.
 	 */
 	if (test_tsk_thread_flag(task, TIF_MEMDIE)) {
-		if (!force_kill)
+		if (oc->order != -1)
 			return OOM_SCAN_ABORT;
 	}
 	if (!task->mm)
@@ -280,7 +278,7 @@ enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
 	if (oom_task_origin(task))
 		return OOM_SCAN_SELECT;
 
-	if (task_will_free_mem(task) && !force_kill)
+	if (task_will_free_mem(task) && oc->order != -1)
 		return OOM_SCAN_ABORT;
 
 	return OOM_SCAN_OK;
@@ -289,12 +287,9 @@ enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
 /*
  * Simple selection loop. We chose the process with the highest
  * number of 'points'.  Returns -1 on scan abort.
- *
- * (not docbooked, we don't want this one cluttering up the manual)
  */
-static struct task_struct *select_bad_process(unsigned int *ppoints,
-		unsigned long totalpages, const nodemask_t *nodemask,
-		bool force_kill)
+static struct task_struct *select_bad_process(struct oom_control *oc,
+		unsigned int *ppoints, unsigned long totalpages)
 {
 	struct task_struct *g, *p;
 	struct task_struct *chosen = NULL;
@@ -304,8 +299,7 @@ static struct task_struct *select_bad_process(unsigned int *ppoints,
 	for_each_process_thread(g, p) {
 		unsigned int points;
 
-		switch (oom_scan_process_thread(p, totalpages, nodemask,
-						force_kill)) {
+		switch (oom_scan_process_thread(oc, p, totalpages)) {
 		case OOM_SCAN_SELECT:
 			chosen = p;
 			chosen_points = ULONG_MAX;
@@ -318,7 +312,7 @@ static struct task_struct *select_bad_process(unsigned int *ppoints,
 		case OOM_SCAN_OK:
 			break;
 		};
-		points = oom_badness(p, NULL, nodemask, totalpages);
+		points = oom_badness(p, NULL, oc->nodemask, totalpages);
 		if (!points || points < chosen_points)
 			continue;
 		/* Prefer thread group leaders for display purposes */
@@ -380,13 +374,13 @@ static void dump_tasks(struct mem_cgroup *memcg, const nodemask_t *nodemask)
 	rcu_read_unlock();
 }
 
-static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order,
-			struct mem_cgroup *memcg, const nodemask_t *nodemask)
+static void dump_header(struct oom_control *oc, struct task_struct *p,
+			struct mem_cgroup *memcg)
 {
 	task_lock(current);
 	pr_warning("%s invoked oom-killer: gfp_mask=0x%x, order=%d, "
 		"oom_score_adj=%hd\n",
-		current->comm, gfp_mask, order,
+		current->comm, oc->gfp_mask, oc->order,
 		current->signal->oom_score_adj);
 	cpuset_print_task_mems_allowed(current);
 	task_unlock(current);
@@ -396,7 +390,7 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order,
 	else
 		show_mem(SHOW_MEM_FILTER_NODES);
 	if (sysctl_oom_dump_tasks)
-		dump_tasks(memcg, nodemask);
+		dump_tasks(memcg, oc->nodemask);
 }
 
 /*
@@ -487,10 +481,9 @@ void oom_killer_enable(void)
  * Must be called while holding a reference to p, which will be released upon
  * returning.
  */
-void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
+void oom_kill_process(struct oom_control *oc, struct task_struct *p,
 		      unsigned int points, unsigned long totalpages,
-		      struct mem_cgroup *memcg, nodemask_t *nodemask,
-		      const char *message)
+		      struct mem_cgroup *memcg, const char *message)
 {
 	struct task_struct *victim = p;
 	struct task_struct *child;
@@ -514,7 +507,7 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
 	task_unlock(p);
 
 	if (__ratelimit(&oom_rs))
-		dump_header(p, gfp_mask, order, memcg, nodemask);
+		dump_header(oc, p, memcg);
 
 	task_lock(p);
 	pr_err("%s: Kill process %d (%s) score %u or sacrifice child\n",
@@ -537,7 +530,7 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
 			/*
 			 * oom_badness() returns 0 if the thread is unkillable
 			 */
-			child_points = oom_badness(child, memcg, nodemask,
+			child_points = oom_badness(child, memcg, oc->nodemask,
 								totalpages);
 			if (child_points > victim_points) {
 				put_task_struct(victim);
@@ -600,8 +593,7 @@ void oom_kill_process(struct task_struct *p, gfp_t gfp_mask, int order,
 /*
  * Determines whether the kernel must panic because of the panic_on_oom sysctl.
  */
-void check_panic_on_oom(enum oom_constraint constraint, gfp_t gfp_mask,
-			int order, const nodemask_t *nodemask,
+void check_panic_on_oom(struct oom_control *oc, enum oom_constraint constraint,
 			struct mem_cgroup *memcg)
 {
 	if (likely(!sysctl_panic_on_oom))
@@ -615,7 +607,10 @@ void check_panic_on_oom(enum oom_constraint constraint, gfp_t gfp_mask,
 		if (constraint != CONSTRAINT_NONE)
 			return;
 	}
-	dump_header(NULL, gfp_mask, order, memcg, nodemask);
+	/* Do not panic for oom kills triggered by sysrq */
+	if (oc->order == -1)
+		return;
+	dump_header(oc, NULL, memcg);
 	panic("Out of memory: %s panic_on_oom is enabled\n",
 		sysctl_panic_on_oom == 2 ? "compulsory" : "system-wide");
 }
@@ -635,28 +630,21 @@ int unregister_oom_notifier(struct notifier_block *nb)
 EXPORT_SYMBOL_GPL(unregister_oom_notifier);
 
 /**
- * __out_of_memory - kill the "best" process when we run out of memory
- * @zonelist: zonelist pointer
- * @gfp_mask: memory allocation flags
- * @order: amount of memory being requested as a power of 2
- * @nodemask: nodemask passed to page allocator
- * @force_kill: true if a task must be killed, even if others are exiting
+ * out_of_memory - kill the "best" process when we run out of memory
+ * @oc: pointer to struct oom_control
  *
  * If we run out of memory, we have the choice between either
  * killing a random task (bad), letting the system crash (worse)
  * OR try to be smart about which process to kill. Note that we
  * don't have to be perfect here, we just have to be good.
  */
-bool out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
-		   int order, nodemask_t *nodemask, bool force_kill)
+bool out_of_memory(struct oom_control *oc)
 {
-	const nodemask_t *mpol_mask;
 	struct task_struct *p;
 	unsigned long totalpages;
 	unsigned long freed = 0;
 	unsigned int uninitialized_var(points);
 	enum oom_constraint constraint = CONSTRAINT_NONE;
-	int killed = 0;
 
 	if (oom_killer_disabled)
 		return false;
@@ -664,7 +652,7 @@ bool out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
 	blocking_notifier_call_chain(&oom_notify_list, 0, &freed);
 	if (freed > 0)
 		/* Got some memory back in the last second. */
-		goto out;
+		return true;
 
 	/*
 	 * If current has a pending SIGKILL or is exiting, then automatically
@@ -677,47 +665,42 @@ bool out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
 	if (current->mm &&
 	    (fatal_signal_pending(current) || task_will_free_mem(current))) {
 		mark_oom_victim(current);
-		goto out;
+		return true;
 	}
 
 	/*
 	 * Check if there were limitations on the allocation (only relevant for
 	 * NUMA) that may require different handling.
 	 */
-	constraint = constrained_alloc(zonelist, gfp_mask, nodemask,
-						&totalpages);
-	mpol_mask = (constraint == CONSTRAINT_MEMORY_POLICY) ? nodemask : NULL;
-	check_panic_on_oom(constraint, gfp_mask, order, mpol_mask, NULL);
+	constraint = constrained_alloc(oc, &totalpages);
+	if (constraint != CONSTRAINT_MEMORY_POLICY)
+		oc->nodemask = NULL;
+	check_panic_on_oom(oc, constraint, NULL);
 
 	if (sysctl_oom_kill_allocating_task && current->mm &&
-	    !oom_unkillable_task(current, NULL, nodemask) &&
+	    !oom_unkillable_task(current, NULL, oc->nodemask) &&
 	    current->signal->oom_score_adj != OOM_SCORE_ADJ_MIN) {
 		get_task_struct(current);
-		oom_kill_process(current, gfp_mask, order, 0, totalpages, NULL,
-				 nodemask,
+		oom_kill_process(oc, current, 0, totalpages, NULL,
 				 "Out of memory (oom_kill_allocating_task)");
-		goto out;
+		return true;
 	}
 
-	p = select_bad_process(&points, totalpages, mpol_mask, force_kill);
+	p = select_bad_process(oc, &points, totalpages);
 	/* Found nothing?!?! Either we hang forever, or we panic. */
-	if (!p) {
-		dump_header(NULL, gfp_mask, order, NULL, mpol_mask);
+	if (!p && oc->order != -1) {
+		dump_header(oc, NULL, NULL);
 		panic("Out of memory and no killable processes...\n");
 	}
-	if (p != (void *)-1UL) {
-		oom_kill_process(p, gfp_mask, order, points, totalpages, NULL,
-				 nodemask, "Out of memory");
-		killed = 1;
-	}
-out:
-	/*
-	 * Give the killed threads a good chance of exiting before trying to
-	 * allocate memory again.
-	 */
-	if (killed)
+	if (p && p != (void *)-1UL) {
+		oom_kill_process(oc, p, points, totalpages, NULL,
+				 "Out of memory");
+		/*
+		 * Give the killed process a good chance to exit before trying
+		 * to allocate memory again.
+		 */
 		schedule_timeout_killable(1);
-
+	}
 	return true;
 }
 
@@ -728,13 +711,20 @@ out:
  */
 void pagefault_out_of_memory(void)
 {
+	struct oom_control oc = {
+		.zonelist = NULL,
+		.nodemask = NULL,
+		.gfp_mask = 0,
+		.order = 0,
+	};
+
 	if (mem_cgroup_oom_synchronize(true))
 		return;
 
 	if (!mutex_trylock(&oom_lock))
 		return;
 
-	if (!out_of_memory(NULL, 0, 0, NULL, false)) {
+	if (!out_of_memory(&oc)) {
 		/*
 		 * There shouldn't be any user tasks runnable while the
 		 * OOM killer is disabled, so the current task has to
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index b401d40..48aaf7b 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -125,6 +125,24 @@ unsigned long dirty_balance_reserve __read_mostly;
 int percpu_pagelist_fraction;
 gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
 
+/*
+ * A cached value of the page's pageblock's migratetype, used when the page is
+ * put on a pcplist. Used to avoid the pageblock migratetype lookup when
+ * freeing from pcplists in most cases, at the cost of possibly becoming stale.
+ * Also the migratetype set in the page does not necessarily match the pcplist
+ * index, e.g. page might have MIGRATE_CMA set but be on a pcplist with any
+ * other index - this ensures that it will be put on the correct CMA freelist.
+ */
+static inline int get_pcppage_migratetype(struct page *page)
+{
+	return page->index;
+}
+
+static inline void set_pcppage_migratetype(struct page *page, int migratetype)
+{
+	page->index = migratetype;
+}
+
 #ifdef CONFIG_PM_SLEEP
 /*
  * The following functions are used by the suspend/hibernate code to temporarily
@@ -791,7 +809,11 @@ static void free_pcppages_bulk(struct zone *zone, int count,
 			page = list_entry(list->prev, struct page, lru);
 			/* must delete as __free_one_page list manipulates */
 			list_del(&page->lru);
-			mt = get_freepage_migratetype(page);
+
+			mt = get_pcppage_migratetype(page);
+			/* MIGRATE_ISOLATE page should not go to pcplists */
+			VM_BUG_ON_PAGE(is_migrate_isolate(mt), page);
+			/* Pageblock could have been isolated meanwhile */
 			if (unlikely(has_isolate_pageblock(zone)))
 				mt = get_pageblock_migratetype(page);
 
@@ -955,7 +977,6 @@ static void __free_pages_ok(struct page *page, unsigned int order)
 	migratetype = get_pfnblock_migratetype(page, pfn);
 	local_irq_save(flags);
 	__count_vm_events(PGFREE, 1 << order);
-	set_freepage_migratetype(page, migratetype);
 	free_one_page(page_zone(page), page, pfn, order, migratetype);
 	local_irq_restore(flags);
 }
@@ -1383,7 +1404,7 @@ struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
 		rmv_page_order(page);
 		area->nr_free--;
 		expand(zone, page, order, current_order, area, migratetype);
-		set_freepage_migratetype(page, migratetype);
+		set_pcppage_migratetype(page, migratetype);
 		return page;
 	}
 
@@ -1460,7 +1481,6 @@ int move_freepages(struct zone *zone,
 		order = page_order(page);
 		list_move(&page->lru,
 			  &zone->free_area[order].free_list[migratetype]);
-		set_freepage_migratetype(page, migratetype);
 		page += 1 << order;
 		pages_moved += 1 << order;
 	}
@@ -1630,14 +1650,13 @@ __rmqueue_fallback(struct zone *zone, unsigned int order, int start_migratetype)
 		expand(zone, page, order, current_order, area,
 					start_migratetype);
 		/*
-		 * The freepage_migratetype may differ from pageblock's
+		 * The pcppage_migratetype may differ from pageblock's
 		 * migratetype depending on the decisions in
-		 * try_to_steal_freepages(). This is OK as long as it
-		 * does not differ for MIGRATE_CMA pageblocks. For CMA
-		 * we need to make sure unallocated pages flushed from
-		 * pcp lists are returned to the correct freelist.
+		 * find_suitable_fallback(). This is OK as long as it does not
+		 * differ for MIGRATE_CMA pageblocks. Those can be used as
+		 * fallback only via special __rmqueue_cma_fallback() function
 		 */
-		set_freepage_migratetype(page, start_migratetype);
+		set_pcppage_migratetype(page, start_migratetype);
 
 		trace_mm_page_alloc_extfrag(page, order, current_order,
 			start_migratetype, fallback_mt);
@@ -1713,7 +1732,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
 		else
 			list_add_tail(&page->lru, list);
 		list = &page->lru;
-		if (is_migrate_cma(get_freepage_migratetype(page)))
+		if (is_migrate_cma(get_pcppage_migratetype(page)))
 			__mod_zone_page_state(zone, NR_FREE_CMA_PAGES,
 					      -(1 << order));
 	}
@@ -1910,7 +1929,7 @@ void free_hot_cold_page(struct page *page, bool cold)
 		return;
 
 	migratetype = get_pfnblock_migratetype(page, pfn);
-	set_freepage_migratetype(page, migratetype);
+	set_pcppage_migratetype(page, migratetype);
 	local_irq_save(flags);
 	__count_vm_event(PGFREE);
 
@@ -2115,7 +2134,7 @@ struct page *buffered_rmqueue(struct zone *preferred_zone,
 		if (!page)
 			goto failed;
 		__mod_zone_freepage_state(zone, -(1 << order),
-					  get_freepage_migratetype(page));
+					  get_pcppage_migratetype(page));
 	}
 
 	__mod_zone_page_state(zone, NR_ALLOC_BATCH, -(1 << order));
@@ -2696,6 +2715,12 @@ static inline struct page *
 __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
 	const struct alloc_context *ac, unsigned long *did_some_progress)
 {
+	struct oom_control oc = {
+		.zonelist = ac->zonelist,
+		.nodemask = ac->nodemask,
+		.gfp_mask = gfp_mask,
+		.order = order,
+	};
 	struct page *page;
 
 	*did_some_progress = 0;
@@ -2747,8 +2772,7 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
 			goto out;
 	}
 	/* Exhausted what can be done so it's blamo time */
-	if (out_of_memory(ac->zonelist, gfp_mask, order, ac->nodemask, false)
-			|| WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL))
+	if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL))
 		*did_some_progress = 1;
 out:
 	mutex_unlock(&oom_lock);
@@ -3490,8 +3514,6 @@ EXPORT_SYMBOL(alloc_pages_exact);
  *
  * Like alloc_pages_exact(), but try to allocate on node nid first before falling
  * back.
- * Note this is not alloc_pages_exact_node() which allocates on a specific node,
- * but is not exact.
  */
 void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask)
 {
@@ -5066,7 +5088,7 @@ static unsigned long __meminit zone_spanned_pages_in_node(int nid,
 {
 	unsigned long zone_start_pfn, zone_end_pfn;
 
-	/* When hotadd a new node, the node should be empty */
+	/* When hotadd a new node from cpu_up(), the node should be empty */
 	if (!node_start_pfn && !node_end_pfn)
 		return 0;
 
@@ -5133,7 +5155,7 @@ static unsigned long __meminit zone_absent_pages_in_node(int nid,
 	unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
 	unsigned long zone_start_pfn, zone_end_pfn;
 
-	/* When hotadd a new node, the node should be empty */
+	/* When hotadd a new node from cpu_up(), the node should be empty */
 	if (!node_start_pfn && !node_end_pfn)
 		return 0;
 
@@ -5306,8 +5328,7 @@ static unsigned long __paginginit calc_memmap_size(unsigned long spanned_pages,
  *
  * NOTE: pgdat should get zeroed by caller.
  */
-static void __paginginit free_area_init_core(struct pglist_data *pgdat,
-		unsigned long node_start_pfn, unsigned long node_end_pfn)
+static void __paginginit free_area_init_core(struct pglist_data *pgdat)
 {
 	enum zone_type j;
 	int nid = pgdat->node_id;
@@ -5458,7 +5479,8 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 	get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
 	pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid,
-		(u64)start_pfn << PAGE_SHIFT, ((u64)end_pfn << PAGE_SHIFT) - 1);
+		(u64)start_pfn << PAGE_SHIFT,
+		end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0);
 #endif
 	calculate_node_totalpages(pgdat, start_pfn, end_pfn,
 				  zones_size, zholes_size);
@@ -5470,7 +5492,7 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
 		(unsigned long)pgdat->node_mem_map);
 #endif
 
-	free_area_init_core(pgdat, start_pfn, end_pfn);
+	free_area_init_core(pgdat);
 }
 
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
@@ -5481,11 +5503,9 @@ void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
  */
 void __init setup_nr_node_ids(void)
 {
-	unsigned int node;
-	unsigned int highest = 0;
+	unsigned int highest;
 
-	for_each_node_mask(node, node_possible_map)
-		highest = node;
+	highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES);
 	nr_node_ids = highest + 1;
 }
 #endif
@@ -6006,7 +6026,7 @@ void __init mem_init_print_info(const char *str)
  * set_dma_reserve - set the specified number of pages reserved in the first zone
  * @new_dma_reserve: The number of pages to mark reserved
  *
- * The per-cpu batchsize and zone watermarks are determined by present_pages.
+ * The per-cpu batchsize and zone watermarks are determined by managed_pages.
  * In the DMA zone, a significant percentage may be consumed by kernel image
  * and other unfreeable allocations which can skew the watermarks badly. This
  * function may optionally be used to account for unfreeable pages in the
@@ -6059,7 +6079,7 @@ void __init page_alloc_init(void)
 }
 
 /*
- * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
+ * calculate_totalreserve_pages - called when sysctl_lowmem_reserve_ratio
  *	or min_free_kbytes changes.
  */
 static void calculate_totalreserve_pages(void)
@@ -6103,7 +6123,7 @@ static void calculate_totalreserve_pages(void)
 
 /*
  * setup_per_zone_lowmem_reserve - called whenever
- *	sysctl_lower_zone_reserve_ratio changes.  Ensures that each zone
+ *	sysctl_lowmem_reserve_ratio changes.  Ensures that each zone
  *	has a correct pages reserved value, so an adequate number of
  *	pages are left in the zone after a successful __alloc_pages().
  */
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 303c908..4568fd5 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -9,7 +9,8 @@
 #include <linux/hugetlb.h>
 #include "internal.h"
 
-int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages)
+static int set_migratetype_isolate(struct page *page,
+				bool skip_hwpoisoned_pages)
 {
 	struct zone *zone;
 	unsigned long flags, pfn;
@@ -72,7 +73,7 @@ out:
 	return ret;
 }
 
-void unset_migratetype_isolate(struct page *page, unsigned migratetype)
+static void unset_migratetype_isolate(struct page *page, unsigned migratetype)
 {
 	struct zone *zone;
 	unsigned long flags, nr_pages;
@@ -223,34 +224,16 @@ __test_page_isolated_in_pageblock(unsigned long pfn, unsigned long end_pfn,
 			continue;
 		}
 		page = pfn_to_page(pfn);
-		if (PageBuddy(page)) {
+		if (PageBuddy(page))
 			/*
-			 * If race between isolatation and allocation happens,
-			 * some free pages could be in MIGRATE_MOVABLE list
-			 * although pageblock's migratation type of the page
-			 * is MIGRATE_ISOLATE. Catch it and move the page into
-			 * MIGRATE_ISOLATE list.
+			 * If the page is on a free list, it has to be on
+			 * the correct MIGRATE_ISOLATE freelist. There is no
+			 * simple way to verify that as VM_BUG_ON(), though.
 			 */
-			if (get_freepage_migratetype(page) != MIGRATE_ISOLATE) {
-				struct page *end_page;
-
-				end_page = page + (1 << page_order(page)) - 1;
-				move_freepages(page_zone(page), page, end_page,
-						MIGRATE_ISOLATE);
-			}
 			pfn += 1 << page_order(page);
-		}
-		else if (page_count(page) == 0 &&
-			get_freepage_migratetype(page) == MIGRATE_ISOLATE)
-			pfn += 1;
-		else if (skip_hwpoisoned_pages && PageHWPoison(page)) {
-			/*
-			 * The HWPoisoned page may be not in buddy
-			 * system, and page_count() is not 0.
-			 */
+		else if (skip_hwpoisoned_pages && PageHWPoison(page))
+			/* A HWPoisoned page cannot be also PageBuddy */
 			pfn++;
-			continue;
-		}
 		else
 			break;
 	}
diff --git a/mm/shmem.c b/mm/shmem.c
index dbe0c1e..48ce829 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -542,6 +542,21 @@ void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
 }
 EXPORT_SYMBOL_GPL(shmem_truncate_range);
 
+static int shmem_getattr(struct vfsmount *mnt, struct dentry *dentry,
+			 struct kstat *stat)
+{
+	struct inode *inode = dentry->d_inode;
+	struct shmem_inode_info *info = SHMEM_I(inode);
+
+	spin_lock(&info->lock);
+	shmem_recalc_inode(inode);
+	spin_unlock(&info->lock);
+
+	generic_fillattr(inode, stat);
+
+	return 0;
+}
+
 static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
 {
 	struct inode *inode = d_inode(dentry);
@@ -3122,6 +3137,7 @@ static const struct file_operations shmem_file_operations = {
 };
 
 static const struct inode_operations shmem_inode_operations = {
+	.getattr	= shmem_getattr,
 	.setattr	= shmem_setattr,
 #ifdef CONFIG_TMPFS_XATTR
 	.setxattr	= shmem_setxattr,
diff --git a/mm/slab.c b/mm/slab.c
index 60c9369..c77ebe6 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -1595,7 +1595,7 @@ static struct page *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
 	if (memcg_charge_slab(cachep, flags, cachep->gfporder))
 		return NULL;
 
-	page = alloc_pages_exact_node(nodeid, flags | __GFP_NOTRACK, cachep->gfporder);
+	page = __alloc_pages_node(nodeid, flags | __GFP_NOTRACK, cachep->gfporder);
 	if (!page) {
 		memcg_uncharge_slab(cachep, cachep->gfporder);
 		slab_out_of_memory(cachep, flags, nodeid);
diff --git a/mm/slab_common.c b/mm/slab_common.c
index c26829f..5ce4fae 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -500,7 +500,7 @@ void memcg_create_kmem_cache(struct mem_cgroup *memcg,
 			     struct kmem_cache *root_cache)
 {
 	static char memcg_name_buf[NAME_MAX + 1]; /* protected by slab_mutex */
-	struct cgroup_subsys_state *css = mem_cgroup_css(memcg);
+	struct cgroup_subsys_state *css = &memcg->css;
 	struct memcg_cache_array *arr;
 	struct kmem_cache *s = NULL;
 	char *cache_name;
@@ -640,6 +640,9 @@ void kmem_cache_destroy(struct kmem_cache *s)
 	bool need_rcu_barrier = false;
 	bool busy = false;
 
+	if (unlikely(!s))
+		return;
+
 	BUG_ON(!is_root_cache(s));
 
 	get_online_cpus();
diff --git a/mm/slob.c b/mm/slob.c
index 165bbd3..0d7e5df 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -45,7 +45,7 @@
  * NUMA support in SLOB is fairly simplistic, pushing most of the real
  * logic down to the page allocator, and simply doing the node accounting
  * on the upper levels. In the event that a node id is explicitly
- * provided, alloc_pages_exact_node() with the specified node id is used
+ * provided, __alloc_pages_node() with the specified node id is used
  * instead. The common case (or when the node id isn't explicitly provided)
  * will default to the current node, as per numa_node_id().
  *
@@ -193,7 +193,7 @@ static void *slob_new_pages(gfp_t gfp, int order, int node)
 
 #ifdef CONFIG_NUMA
 	if (node != NUMA_NO_NODE)
-		page = alloc_pages_exact_node(node, gfp, order);
+		page = __alloc_pages_node(node, gfp, order);
 	else
 #endif
 		page = alloc_pages(gfp, order);
diff --git a/mm/slub.c b/mm/slub.c
index 084184e..f614b5d 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1334,7 +1334,7 @@ static inline struct page *alloc_slab_page(struct kmem_cache *s,
 	if (node == NUMA_NO_NODE)
 		page = alloc_pages(flags, order);
 	else
-		page = alloc_pages_exact_node(node, flags, order);
+		page = __alloc_pages_node(node, flags, order);
 
 	if (!page)
 		memcg_uncharge_slab(s, order);
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 8bc8e66..d504adb 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -288,17 +288,14 @@ struct page * lookup_swap_cache(swp_entry_t entry)
 	return page;
 }
 
-/* 
- * Locate a page of swap in physical memory, reserving swap cache space
- * and reading the disk if it is not already cached.
- * A failure return means that either the page allocation failed or that
- * the swap entry is no longer in use.
- */
-struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
-			struct vm_area_struct *vma, unsigned long addr)
+struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
+			struct vm_area_struct *vma, unsigned long addr,
+			bool *new_page_allocated)
 {
 	struct page *found_page, *new_page = NULL;
+	struct address_space *swapper_space = swap_address_space(entry);
 	int err;
+	*new_page_allocated = false;
 
 	do {
 		/*
@@ -306,8 +303,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
 		 * called after lookup_swap_cache() failed, re-calling
 		 * that would confuse statistics.
 		 */
-		found_page = find_get_page(swap_address_space(entry),
-					entry.val);
+		found_page = find_get_page(swapper_space, entry.val);
 		if (found_page)
 			break;
 
@@ -366,7 +362,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
 			 * Initiate read into locked page and return.
 			 */
 			lru_cache_add_anon(new_page);
-			swap_readpage(new_page);
+			*new_page_allocated = true;
 			return new_page;
 		}
 		radix_tree_preload_end();
@@ -384,6 +380,25 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
 	return found_page;
 }
 
+/*
+ * Locate a page of swap in physical memory, reserving swap cache space
+ * and reading the disk if it is not already cached.
+ * A failure return means that either the page allocation failed or that
+ * the swap entry is no longer in use.
+ */
+struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
+			struct vm_area_struct *vma, unsigned long addr)
+{
+	bool page_was_allocated;
+	struct page *retpage = __read_swap_cache_async(entry, gfp_mask,
+			vma, addr, &page_was_allocated);
+
+	if (page_was_allocated)
+		swap_readpage(retpage);
+
+	return retpage;
+}
+
 static unsigned long swapin_nr_pages(unsigned long offset)
 {
 	static unsigned long prev_offset;
diff --git a/mm/swapfile.c b/mm/swapfile.c
index aebc2dd6e..5887731 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -875,6 +875,48 @@ int page_swapcount(struct page *page)
 }
 
 /*
+ * How many references to @entry are currently swapped out?
+ * This considers COUNT_CONTINUED so it returns exact answer.
+ */
+int swp_swapcount(swp_entry_t entry)
+{
+	int count, tmp_count, n;
+	struct swap_info_struct *p;
+	struct page *page;
+	pgoff_t offset;
+	unsigned char *map;
+
+	p = swap_info_get(entry);
+	if (!p)
+		return 0;
+
+	count = swap_count(p->swap_map[swp_offset(entry)]);
+	if (!(count & COUNT_CONTINUED))
+		goto out;
+
+	count &= ~COUNT_CONTINUED;
+	n = SWAP_MAP_MAX + 1;
+
+	offset = swp_offset(entry);
+	page = vmalloc_to_page(p->swap_map + offset);
+	offset &= ~PAGE_MASK;
+	VM_BUG_ON(page_private(page) != SWP_CONTINUED);
+
+	do {
+		page = list_entry(page->lru.next, struct page, lru);
+		map = kmap_atomic(page);
+		tmp_count = map[offset];
+		kunmap_atomic(map);
+
+		count += (tmp_count & ~COUNT_CONTINUED) * n;
+		n *= (SWAP_CONT_MAX + 1);
+	} while (tmp_count & COUNT_CONTINUED);
+out:
+	spin_unlock(&p->lock);
+	return count;
+}
+
+/*
  * We can write to an anon page without COW if there are no other references
  * to it.  And as a side-effect, free up its swap: because the old content
  * on disk will never be read, and seeking back there to write new content
diff --git a/mm/vmscan.c b/mm/vmscan.c
index b113903..2d978b2 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -175,7 +175,7 @@ static bool sane_reclaim(struct scan_control *sc)
 	if (!memcg)
 		return true;
 #ifdef CONFIG_CGROUP_WRITEBACK
-	if (cgroup_on_dfl(mem_cgroup_css(memcg)->cgroup))
+	if (memcg->css.cgroup)
 		return true;
 #endif
 	return false;
@@ -985,7 +985,7 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 		 *    __GFP_IO|__GFP_FS for this reason); but more thought
 		 *    would probably show more reasons.
 		 *
-		 * 3) Legacy memcg encounters a page that is not already marked
+		 * 3) Legacy memcg encounters a page that is already marked
 		 *    PageReclaim. memcg does not have any dirty pages
 		 *    throttling so we could easily OOM just because too many
 		 *    pages are in writeback and there is nothing else to
@@ -1015,12 +1015,15 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 				 */
 				SetPageReclaim(page);
 				nr_writeback++;
-
 				goto keep_locked;
 
 			/* Case 3 above */
 			} else {
+				unlock_page(page);
 				wait_on_page_writeback(page);
+				/* then go back and try same page again */
+				list_add_tail(&page->lru, page_list);
+				continue;
 			}
 		}
 
@@ -1196,7 +1199,7 @@ cull_mlocked:
 		if (PageSwapCache(page))
 			try_to_free_swap(page);
 		unlock_page(page);
-		putback_lru_page(page);
+		list_add(&page->lru, &ret_pages);
 		continue;
 
 activate_locked:
@@ -1359,7 +1362,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
 	unsigned long nr_taken = 0;
 	unsigned long scan;
 
-	for (scan = 0; scan < nr_to_scan && !list_empty(src); scan++) {
+	for (scan = 0; scan < nr_to_scan && nr_taken < nr_to_scan &&
+					!list_empty(src); scan++) {
 		struct page *page;
 		int nr_pages;
 
diff --git a/mm/zbud.c b/mm/zbud.c
index f3bf6f7..fa48bcdf 100644
--- a/mm/zbud.c
+++ b/mm/zbud.c
@@ -96,10 +96,10 @@ struct zbud_pool {
 	struct list_head buddied;
 	struct list_head lru;
 	u64 pages_nr;
-	struct zbud_ops *ops;
+	const struct zbud_ops *ops;
 #ifdef CONFIG_ZPOOL
 	struct zpool *zpool;
-	struct zpool_ops *zpool_ops;
+	const struct zpool_ops *zpool_ops;
 #endif
 };
 
@@ -133,12 +133,12 @@ static int zbud_zpool_evict(struct zbud_pool *pool, unsigned long handle)
 		return -ENOENT;
 }
 
-static struct zbud_ops zbud_zpool_ops = {
+static const struct zbud_ops zbud_zpool_ops = {
 	.evict =	zbud_zpool_evict
 };
 
 static void *zbud_zpool_create(char *name, gfp_t gfp,
-			       struct zpool_ops *zpool_ops,
+			       const struct zpool_ops *zpool_ops,
 			       struct zpool *zpool)
 {
 	struct zbud_pool *pool;
@@ -302,7 +302,7 @@ static int num_free_chunks(struct zbud_header *zhdr)
  * Return: pointer to the new zbud pool or NULL if the metadata allocation
  * failed.
  */
-struct zbud_pool *zbud_create_pool(gfp_t gfp, struct zbud_ops *ops)
+struct zbud_pool *zbud_create_pool(gfp_t gfp, const struct zbud_ops *ops)
 {
 	struct zbud_pool *pool;
 	int i;
diff --git a/mm/zpool.c b/mm/zpool.c
index 722a4f6..68d2dd8 100644
--- a/mm/zpool.c
+++ b/mm/zpool.c
@@ -22,7 +22,7 @@ struct zpool {
 
 	struct zpool_driver *driver;
 	void *pool;
-	struct zpool_ops *ops;
+	const struct zpool_ops *ops;
 
 	struct list_head list;
 };
@@ -115,7 +115,7 @@ static void zpool_put_driver(struct zpool_driver *driver)
  * Returns: New zpool on success, NULL on failure.
  */
 struct zpool *zpool_create_pool(char *type, char *name, gfp_t gfp,
-		struct zpool_ops *ops)
+		const struct zpool_ops *ops)
 {
 	struct zpool_driver *driver;
 	struct zpool *zpool;
@@ -320,20 +320,6 @@ u64 zpool_get_total_size(struct zpool *zpool)
 	return zpool->driver->total_size(zpool->pool);
 }
 
-static int __init init_zpool(void)
-{
-	pr_info("loaded\n");
-	return 0;
-}
-
-static void __exit exit_zpool(void)
-{
-	pr_info("unloaded\n");
-}
-
-module_init(init_zpool);
-module_exit(exit_zpool);
-
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");
 MODULE_DESCRIPTION("Common API for compressed memory storage");
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 0a7f81a..f135b1b 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -169,14 +169,12 @@ enum zs_stat_type {
 	NR_ZS_STAT_TYPE,
 };
 
-#ifdef CONFIG_ZSMALLOC_STAT
-
-static struct dentry *zs_stat_root;
-
 struct zs_size_stat {
 	unsigned long objs[NR_ZS_STAT_TYPE];
 };
 
+#ifdef CONFIG_ZSMALLOC_STAT
+static struct dentry *zs_stat_root;
 #endif
 
 /*
@@ -201,6 +199,8 @@ static int zs_size_classes;
 static const int fullness_threshold_frac = 4;
 
 struct size_class {
+	spinlock_t lock;
+	struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS];
 	/*
 	 * Size of objects stored in this class. Must be multiple
 	 * of ZS_ALIGN.
@@ -210,16 +210,10 @@ struct size_class {
 
 	/* Number of PAGE_SIZE sized pages to combine to form a 'zspage' */
 	int pages_per_zspage;
-	/* huge object: pages_per_zspage == 1 && maxobj_per_zspage == 1 */
-	bool huge;
-
-#ifdef CONFIG_ZSMALLOC_STAT
 	struct zs_size_stat stats;
-#endif
-
-	spinlock_t lock;
 
-	struct page *fullness_list[_ZS_NR_FULLNESS_GROUPS];
+	/* huge object: pages_per_zspage == 1 && maxobj_per_zspage == 1 */
+	bool huge;
 };
 
 /*
@@ -251,6 +245,15 @@ struct zs_pool {
 	gfp_t flags;	/* allocation flags used when growing pool */
 	atomic_long_t pages_allocated;
 
+	struct zs_pool_stats stats;
+
+	/* Compact classes */
+	struct shrinker shrinker;
+	/*
+	 * To signify that register_shrinker() was successful
+	 * and unregister_shrinker() will not Oops.
+	 */
+	bool shrinker_enabled;
 #ifdef CONFIG_ZSMALLOC_STAT
 	struct dentry *stat_dentry;
 #endif
@@ -285,8 +288,7 @@ static int create_handle_cache(struct zs_pool *pool)
 
 static void destroy_handle_cache(struct zs_pool *pool)
 {
-	if (pool->handle_cachep)
-		kmem_cache_destroy(pool->handle_cachep);
+	kmem_cache_destroy(pool->handle_cachep);
 }
 
 static unsigned long alloc_handle(struct zs_pool *pool)
@@ -309,7 +311,8 @@ static void record_obj(unsigned long handle, unsigned long obj)
 
 #ifdef CONFIG_ZPOOL
 
-static void *zs_zpool_create(char *name, gfp_t gfp, struct zpool_ops *zpool_ops,
+static void *zs_zpool_create(char *name, gfp_t gfp,
+			     const struct zpool_ops *zpool_ops,
 			     struct zpool *zpool)
 {
 	return zs_create_pool(name, gfp);
@@ -441,8 +444,6 @@ static int get_size_class_index(int size)
 	return min(zs_size_classes - 1, idx);
 }
 
-#ifdef CONFIG_ZSMALLOC_STAT
-
 static inline void zs_stat_inc(struct size_class *class,
 				enum zs_stat_type type, unsigned long cnt)
 {
@@ -461,6 +462,8 @@ static inline unsigned long zs_stat_get(struct size_class *class,
 	return class->stats.objs[type];
 }
 
+#ifdef CONFIG_ZSMALLOC_STAT
+
 static int __init zs_stat_init(void)
 {
 	if (!debugfs_initialized())
@@ -576,23 +579,6 @@ static void zs_pool_stat_destroy(struct zs_pool *pool)
 }
 
 #else /* CONFIG_ZSMALLOC_STAT */
-
-static inline void zs_stat_inc(struct size_class *class,
-				enum zs_stat_type type, unsigned long cnt)
-{
-}
-
-static inline void zs_stat_dec(struct size_class *class,
-				enum zs_stat_type type, unsigned long cnt)
-{
-}
-
-static inline unsigned long zs_stat_get(struct size_class *class,
-				enum zs_stat_type type)
-{
-	return 0;
-}
-
 static int __init zs_stat_init(void)
 {
 	return 0;
@@ -610,7 +596,6 @@ static inline int zs_pool_stat_create(char *name, struct zs_pool *pool)
 static inline void zs_pool_stat_destroy(struct zs_pool *pool)
 {
 }
-
 #endif
 
 
@@ -658,13 +643,22 @@ static void insert_zspage(struct page *page, struct size_class *class,
 	if (fullness >= _ZS_NR_FULLNESS_GROUPS)
 		return;
 
-	head = &class->fullness_list[fullness];
-	if (*head)
-		list_add_tail(&page->lru, &(*head)->lru);
-
-	*head = page;
 	zs_stat_inc(class, fullness == ZS_ALMOST_EMPTY ?
 			CLASS_ALMOST_EMPTY : CLASS_ALMOST_FULL, 1);
+
+	head = &class->fullness_list[fullness];
+	if (!*head) {
+		*head = page;
+		return;
+	}
+
+	/*
+	 * We want to see more ZS_FULL pages and less almost
+	 * empty/full. Put pages with higher ->inuse first.
+	 */
+	list_add_tail(&page->lru, &(*head)->lru);
+	if (page->inuse >= (*head)->inuse)
+		*head = page;
 }
 
 /*
@@ -1495,7 +1489,7 @@ void zs_free(struct zs_pool *pool, unsigned long handle)
 }
 EXPORT_SYMBOL_GPL(zs_free);
 
-static void zs_object_copy(unsigned long src, unsigned long dst,
+static void zs_object_copy(unsigned long dst, unsigned long src,
 				struct size_class *class)
 {
 	struct page *s_page, *d_page;
@@ -1602,8 +1596,6 @@ struct zs_compact_control {
 	 /* Starting object index within @s_page which used for live object
 	  * in the subpage. */
 	int index;
-	/* how many of objects are migrated */
-	int nr_migrated;
 };
 
 static int migrate_zspage(struct zs_pool *pool, struct size_class *class,
@@ -1614,7 +1606,6 @@ static int migrate_zspage(struct zs_pool *pool, struct size_class *class,
 	struct page *s_page = cc->s_page;
 	struct page *d_page = cc->d_page;
 	unsigned long index = cc->index;
-	int nr_migrated = 0;
 	int ret = 0;
 
 	while (1) {
@@ -1636,23 +1627,21 @@ static int migrate_zspage(struct zs_pool *pool, struct size_class *class,
 
 		used_obj = handle_to_obj(handle);
 		free_obj = obj_malloc(d_page, class, handle);
-		zs_object_copy(used_obj, free_obj, class);
+		zs_object_copy(free_obj, used_obj, class);
 		index++;
 		record_obj(handle, free_obj);
 		unpin_tag(handle);
 		obj_free(pool, class, used_obj);
-		nr_migrated++;
 	}
 
 	/* Remember last position in this iteration */
 	cc->s_page = s_page;
 	cc->index = index;
-	cc->nr_migrated = nr_migrated;
 
 	return ret;
 }
 
-static struct page *alloc_target_page(struct size_class *class)
+static struct page *isolate_target_page(struct size_class *class)
 {
 	int i;
 	struct page *page;
@@ -1668,8 +1657,17 @@ static struct page *alloc_target_page(struct size_class *class)
 	return page;
 }
 
-static void putback_zspage(struct zs_pool *pool, struct size_class *class,
-				struct page *first_page)
+/*
+ * putback_zspage - add @first_page into right class's fullness list
+ * @pool: target pool
+ * @class: destination class
+ * @first_page: target page
+ *
+ * Return @fist_page's fullness_group
+ */
+static enum fullness_group putback_zspage(struct zs_pool *pool,
+			struct size_class *class,
+			struct page *first_page)
 {
 	enum fullness_group fullness;
 
@@ -1687,50 +1685,72 @@ static void putback_zspage(struct zs_pool *pool, struct size_class *class,
 
 		free_zspage(first_page);
 	}
+
+	return fullness;
 }
 
 static struct page *isolate_source_page(struct size_class *class)
 {
-	struct page *page;
+	int i;
+	struct page *page = NULL;
 
-	page = class->fullness_list[ZS_ALMOST_EMPTY];
-	if (page)
-		remove_zspage(page, class, ZS_ALMOST_EMPTY);
+	for (i = ZS_ALMOST_EMPTY; i >= ZS_ALMOST_FULL; i--) {
+		page = class->fullness_list[i];
+		if (!page)
+			continue;
+
+		remove_zspage(page, class, i);
+		break;
+	}
 
 	return page;
 }
 
-static unsigned long __zs_compact(struct zs_pool *pool,
-				struct size_class *class)
+/*
+ *
+ * Based on the number of unused allocated objects calculate
+ * and return the number of pages that we can free.
+ */
+static unsigned long zs_can_compact(struct size_class *class)
+{
+	unsigned long obj_wasted;
+
+	obj_wasted = zs_stat_get(class, OBJ_ALLOCATED) -
+		zs_stat_get(class, OBJ_USED);
+
+	obj_wasted /= get_maxobj_per_zspage(class->size,
+			class->pages_per_zspage);
+
+	return obj_wasted * class->pages_per_zspage;
+}
+
+static void __zs_compact(struct zs_pool *pool, struct size_class *class)
 {
-	int nr_to_migrate;
 	struct zs_compact_control cc;
 	struct page *src_page;
 	struct page *dst_page = NULL;
-	unsigned long nr_total_migrated = 0;
 
 	spin_lock(&class->lock);
 	while ((src_page = isolate_source_page(class))) {
 
 		BUG_ON(!is_first_page(src_page));
 
-		/* The goal is to migrate all live objects in source page */
-		nr_to_migrate = src_page->inuse;
+		if (!zs_can_compact(class))
+			break;
+
 		cc.index = 0;
 		cc.s_page = src_page;
 
-		while ((dst_page = alloc_target_page(class))) {
+		while ((dst_page = isolate_target_page(class))) {
 			cc.d_page = dst_page;
 			/*
-			 * If there is no more space in dst_page, try to
-			 * allocate another zspage.
+			 * If there is no more space in dst_page, resched
+			 * and see if anyone had allocated another zspage.
 			 */
 			if (!migrate_zspage(pool, class, &cc))
 				break;
 
 			putback_zspage(pool, class, dst_page);
-			nr_total_migrated += cc.nr_migrated;
-			nr_to_migrate -= cc.nr_migrated;
 		}
 
 		/* Stop if we couldn't find slot */
@@ -1738,9 +1758,9 @@ static unsigned long __zs_compact(struct zs_pool *pool,
 			break;
 
 		putback_zspage(pool, class, dst_page);
-		putback_zspage(pool, class, src_page);
+		if (putback_zspage(pool, class, src_page) == ZS_EMPTY)
+			pool->stats.pages_compacted += class->pages_per_zspage;
 		spin_unlock(&class->lock);
-		nr_total_migrated += cc.nr_migrated;
 		cond_resched();
 		spin_lock(&class->lock);
 	}
@@ -1749,14 +1769,11 @@ static unsigned long __zs_compact(struct zs_pool *pool,
 		putback_zspage(pool, class, src_page);
 
 	spin_unlock(&class->lock);
-
-	return nr_total_migrated;
 }
 
 unsigned long zs_compact(struct zs_pool *pool)
 {
 	int i;
-	unsigned long nr_migrated = 0;
 	struct size_class *class;
 
 	for (i = zs_size_classes - 1; i >= 0; i--) {
@@ -1765,13 +1782,80 @@ unsigned long zs_compact(struct zs_pool *pool)
 			continue;
 		if (class->index != i)
 			continue;
-		nr_migrated += __zs_compact(pool, class);
+		__zs_compact(pool, class);
 	}
 
-	return nr_migrated;
+	return pool->stats.pages_compacted;
 }
 EXPORT_SYMBOL_GPL(zs_compact);
 
+void zs_pool_stats(struct zs_pool *pool, struct zs_pool_stats *stats)
+{
+	memcpy(stats, &pool->stats, sizeof(struct zs_pool_stats));
+}
+EXPORT_SYMBOL_GPL(zs_pool_stats);
+
+static unsigned long zs_shrinker_scan(struct shrinker *shrinker,
+		struct shrink_control *sc)
+{
+	unsigned long pages_freed;
+	struct zs_pool *pool = container_of(shrinker, struct zs_pool,
+			shrinker);
+
+	pages_freed = pool->stats.pages_compacted;
+	/*
+	 * Compact classes and calculate compaction delta.
+	 * Can run concurrently with a manually triggered
+	 * (by user) compaction.
+	 */
+	pages_freed = zs_compact(pool) - pages_freed;
+
+	return pages_freed ? pages_freed : SHRINK_STOP;
+}
+
+static unsigned long zs_shrinker_count(struct shrinker *shrinker,
+		struct shrink_control *sc)
+{
+	int i;
+	struct size_class *class;
+	unsigned long pages_to_free = 0;
+	struct zs_pool *pool = container_of(shrinker, struct zs_pool,
+			shrinker);
+
+	if (!pool->shrinker_enabled)
+		return 0;
+
+	for (i = zs_size_classes - 1; i >= 0; i--) {
+		class = pool->size_class[i];
+		if (!class)
+			continue;
+		if (class->index != i)
+			continue;
+
+		pages_to_free += zs_can_compact(class);
+	}
+
+	return pages_to_free;
+}
+
+static void zs_unregister_shrinker(struct zs_pool *pool)
+{
+	if (pool->shrinker_enabled) {
+		unregister_shrinker(&pool->shrinker);
+		pool->shrinker_enabled = false;
+	}
+}
+
+static int zs_register_shrinker(struct zs_pool *pool)
+{
+	pool->shrinker.scan_objects = zs_shrinker_scan;
+	pool->shrinker.count_objects = zs_shrinker_count;
+	pool->shrinker.batch = 0;
+	pool->shrinker.seeks = DEFAULT_SEEKS;
+
+	return register_shrinker(&pool->shrinker);
+}
+
 /**
  * zs_create_pool - Creates an allocation pool to work from.
  * @flags: allocation flags used to allocate pool metadata
@@ -1857,6 +1941,12 @@ struct zs_pool *zs_create_pool(char *name, gfp_t flags)
 	if (zs_pool_stat_create(name, pool))
 		goto err;
 
+	/*
+	 * Not critical, we still can use the pool
+	 * and user can trigger compaction manually.
+	 */
+	if (zs_register_shrinker(pool) == 0)
+		pool->shrinker_enabled = true;
 	return pool;
 
 err:
@@ -1869,6 +1959,7 @@ void zs_destroy_pool(struct zs_pool *pool)
 {
 	int i;
 
+	zs_unregister_shrinker(pool);
 	zs_pool_stat_destroy(pool);
 
 	for (i = 0; i < zs_size_classes; i++) {
diff --git a/mm/zswap.c b/mm/zswap.c
index 2d5727b..48a1d08 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -446,75 +446,14 @@ enum zswap_get_swap_ret {
 static int zswap_get_swap_cache_page(swp_entry_t entry,
 				struct page **retpage)
 {
-	struct page *found_page, *new_page = NULL;
-	struct address_space *swapper_space = swap_address_space(entry);
-	int err;
+	bool page_was_allocated;
 
-	*retpage = NULL;
-	do {
-		/*
-		 * First check the swap cache.  Since this is normally
-		 * called after lookup_swap_cache() failed, re-calling
-		 * that would confuse statistics.
-		 */
-		found_page = find_get_page(swapper_space, entry.val);
-		if (found_page)
-			break;
-
-		/*
-		 * Get a new page to read into from swap.
-		 */
-		if (!new_page) {
-			new_page = alloc_page(GFP_KERNEL);
-			if (!new_page)
-				break; /* Out of memory */
-		}
-
-		/*
-		 * call radix_tree_preload() while we can wait.
-		 */
-		err = radix_tree_preload(GFP_KERNEL);
-		if (err)
-			break;
-
-		/*
-		 * Swap entry may have been freed since our caller observed it.
-		 */
-		err = swapcache_prepare(entry);
-		if (err == -EEXIST) { /* seems racy */
-			radix_tree_preload_end();
-			continue;
-		}
-		if (err) { /* swp entry is obsolete ? */
-			radix_tree_preload_end();
-			break;
-		}
-
-		/* May fail (-ENOMEM) if radix-tree node allocation failed. */
-		__set_page_locked(new_page);
-		SetPageSwapBacked(new_page);
-		err = __add_to_swap_cache(new_page, entry);
-		if (likely(!err)) {
-			radix_tree_preload_end();
-			lru_cache_add_anon(new_page);
-			*retpage = new_page;
-			return ZSWAP_SWAPCACHE_NEW;
-		}
-		radix_tree_preload_end();
-		ClearPageSwapBacked(new_page);
-		__clear_page_locked(new_page);
-		/*
-		 * add_to_swap_cache() doesn't return -EEXIST, so we can safely
-		 * clear SWAP_HAS_CACHE flag.
-		 */
-		swapcache_free(entry);
-	} while (err != -ENOMEM);
-
-	if (new_page)
-		page_cache_release(new_page);
-	if (!found_page)
+	*retpage = __read_swap_cache_async(entry, GFP_KERNEL,
+			NULL, 0, &page_was_allocated);
+	if (page_was_allocated)
+		return ZSWAP_SWAPCACHE_NEW;
+	if (!*retpage)
 		return ZSWAP_SWAPCACHE_FAIL;
-	*retpage = found_page;
 	return ZSWAP_SWAPCACHE_EXIST;
 }
 
@@ -816,7 +755,7 @@ static void zswap_frontswap_invalidate_area(unsigned type)
 	zswap_trees[type] = NULL;
 }
 
-static struct zpool_ops zswap_zpool_ops = {
+static const struct zpool_ops zswap_zpool_ops = {
 	.evict = zswap_writeback_entry
 };