Merge branch 'akpm' (patches from Andrew)

Merge updates from Andrew Morton: - various misc bits - DAX updates - OCFS2 - most of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (119 commits) mm,fork: introduce MADV_WIPEONFORK x86,mpx: make mpx depend on x86-64 to free up VMA flag mm: add /proc/pid/smaps_rollup mm: hugetlb: clear target sub-page last when clearing huge page mm: oom: let oom_reap_task and exit_mmap run concurrently swap: choose swap device according to numa node mm: replace TIF_MEMDIE checks by tsk_is_oom_victim mm, oom: do not rely on TIF_MEMDIE for memory reserves access z3fold: use per-cpu unbuddied lists mm, swap: don't use VMA based swap readahead if HDD is used as swap mm, swap: add sysfs interface for VMA based swap readahead mm, swap: VMA based swap readahead mm, swap: fix swap readahead marking mm, swap: add swap readahead hit statistics mm/vmalloc.c: don't reinvent the wheel but use existing llist API mm/vmstat.c: fix wrong comment selftests/memfd: add memfd_create hugetlbfs selftest mm/shmem: add hugetlbfs support to memfd_create() mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups mm/vmalloc.c: halve the number of comparisons performed in pcpu_get_vm_areas() ...
author: Linus Torvalds <torvalds@linux-foundation.org> 2017-09-07 06:49:49 +0300
committer: Linus Torvalds <torvalds@linux-foundation.org> 2017-09-07 06:49:49 +0300
commit: d34fc1adf01ff87026da85fb972dc259dc347540 (patch)
tree: 27356073d423187157b7cdb69da32b53102fb9e7 /mm
parent: 1c9fe4409ce3e9c78b1ed96ee8ed699d4f03bf33 (diff)
parent: d2cd9ede6e193dd7d88b6d27399e96229a551b19 (diff)
download: linux-d34fc1adf01ff87026da85fb972dc259dc347540.tar.xz
35 files changed, 1868 insertions, 905 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index 48b1af447fa7..0ded10a22639 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -678,6 +678,7 @@ config ZONE_DEVICE
 	depends on MEMORY_HOTREMOVE
 	depends on SPARSEMEM_VMEMMAP
 	depends on ARCH_HAS_ZONE_DEVICE
+	select RADIX_TREE_MULTIORDER
 
 	help
 	  Device memory hotplug support allows for establishing pmem,
diff --git a/mm/filemap.c b/mm/filemap.c
index 1e01cb6e5173..9d21afd692b9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -130,17 +130,8 @@ static int page_cache_tree_insert(struct address_space *mapping,
 			return -EEXIST;
 
 		mapping->nrexceptional--;
-		if (!dax_mapping(mapping)) {
-			if (shadowp)
-				*shadowp = p;
-		} else {
-			/* DAX can replace empty locked entry with a hole */
-			WARN_ON_ONCE(p !=
-				dax_radix_locked_entry(0, RADIX_DAX_EMPTY));
-			/* Wakeup waiters for exceptional entry lock */
-			dax_wake_mapping_entry_waiter(mapping, page->index, p,
-						      true);
-		}
+		if (shadowp)
+			*shadowp = p;
 	}
 	__radix_tree_replace(&mapping->page_tree, node, slot, page,
 			     workingset_update_node, mapping);
@@ -402,8 +393,7 @@ bool filemap_range_has_page(struct address_space *mapping,
 {
 	pgoff_t index = start_byte >> PAGE_SHIFT;
 	pgoff_t end = end_byte >> PAGE_SHIFT;
-	struct pagevec pvec;
-	bool ret;
+	struct page *page;
 
 	if (end_byte < start_byte)
 		return false;
@@ -411,12 +401,10 @@ bool filemap_range_has_page(struct address_space *mapping,
 	if (mapping->nrpages == 0)
 		return false;
 
-	pagevec_init(&pvec, 0);
-	if (!pagevec_lookup(&pvec, mapping, index, 1))
+	if (!find_get_pages_range(mapping, &index, end, 1, &page))
 		return false;
-	ret = (pvec.pages[0]->index <= end);
-	pagevec_release(&pvec);
-	return ret;
+	put_page(page);
+	return true;
 }
 EXPORT_SYMBOL(filemap_range_has_page);
 
@@ -1564,23 +1552,29 @@ export:
 }
 
 /**
- * find_get_pages - gang pagecache lookup
+ * find_get_pages_range - gang pagecache lookup
  * @mapping:	The address_space to search
  * @start:	The starting page index
+ * @end:	The final page index (inclusive)
  * @nr_pages:	The maximum number of pages
  * @pages:	Where the resulting pages are placed
  *
- * find_get_pages() will search for and return a group of up to
- * @nr_pages pages in the mapping.  The pages are placed at @pages.
- * find_get_pages() takes a reference against the returned pages.
+ * find_get_pages_range() will search for and return a group of up to @nr_pages
+ * pages in the mapping starting at index @start and up to index @end
+ * (inclusive).  The pages are placed at @pages.  find_get_pages_range() takes
+ * a reference against the returned pages.
  *
  * The search returns a group of mapping-contiguous pages with ascending
  * indexes.  There may be holes in the indices due to not-present pages.
+ * We also update @start to index the next page for the traversal.
  *
- * find_get_pages() returns the number of pages which were found.
+ * find_get_pages_range() returns the number of pages which were found. If this
+ * number is smaller than @nr_pages, the end of specified range has been
+ * reached.
  */
-unsigned find_get_pages(struct address_space *mapping, pgoff_t start,
-			    unsigned int nr_pages, struct page **pages)
+unsigned find_get_pages_range(struct address_space *mapping, pgoff_t *start,
+			      pgoff_t end, unsigned int nr_pages,
+			      struct page **pages)
 {
 	struct radix_tree_iter iter;
 	void **slot;
@@ -1590,8 +1584,11 @@ unsigned find_get_pages(struct address_space *mapping, pgoff_t start,
 		return 0;
 
 	rcu_read_lock();
-	radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, start) {
+	radix_tree_for_each_slot(slot, &mapping->page_tree, &iter, *start) {
 		struct page *head, *page;
+
+		if (iter.index > end)
+			break;
 repeat:
 		page = radix_tree_deref_slot(slot);
 		if (unlikely(!page))
@@ -1627,11 +1624,25 @@ repeat:
 		}
 
 		pages[ret] = page;
-		if (++ret == nr_pages)
-			break;
+		if (++ret == nr_pages) {
+			*start = pages[ret - 1]->index + 1;
+			goto out;
+		}
 	}
 
+	/*
+	 * We come here when there is no page beyond @end. We take care to not
+	 * overflow the index @start as it confuses some of the callers. This
+	 * breaks the iteration when there is page at index -1 but that is
+	 * already broken anyway.
+	 */
+	if (end == (pgoff_t)-1)
+		*start = (pgoff_t)-1;
+	else
+		*start = end + 1;
+out:
 	rcu_read_unlock();
+
 	return ret;
 }
 
diff --git a/mm/gup.c b/mm/gup.c
index 23f01c40c88f..33d651deeae2 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1352,7 +1352,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end,
 }
 #endif /* __HAVE_ARCH_PTE_SPECIAL */
 
-#ifdef __HAVE_ARCH_PTE_DEVMAP
+#if defined(__HAVE_ARCH_PTE_DEVMAP) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
 static int __gup_device_huge(unsigned long pfn, unsigned long addr,
 		unsigned long end, struct page **pages, int *nr)
 {
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 3644ff918434..0b51e70e0a8b 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -328,7 +328,7 @@ static struct attribute *hugepage_attr[] = {
 	NULL,
 };
 
-static struct attribute_group hugepage_attr_group = {
+static const struct attribute_group hugepage_attr_group = {
 	.attrs = hugepage_attr,
 };
 
@@ -567,7 +567,7 @@ static int __do_huge_pmd_anonymous_page(struct vm_fault *vmf, struct page *page,
 		goto release;
 	}
 
-	clear_huge_page(page, haddr, HPAGE_PMD_NR);
+	clear_huge_page(page, vmf->address, HPAGE_PMD_NR);
 	/*
 	 * The memory barrier inside __SetPageUptodate makes sure that
 	 * clear_huge_page writes become visible before the set_pmd_at()
@@ -1240,15 +1240,29 @@ int do_huge_pmd_wp_page(struct vm_fault *vmf, pmd_t orig_pmd)
 	 * We can only reuse the page if nobody else maps the huge page or it's
 	 * part.
 	 */
-	if (page_trans_huge_mapcount(page, NULL) == 1) {
+	if (!trylock_page(page)) {
+		get_page(page);
+		spin_unlock(vmf->ptl);
+		lock_page(page);
+		spin_lock(vmf->ptl);
+		if (unlikely(!pmd_same(*vmf->pmd, orig_pmd))) {
+			unlock_page(page);
+			put_page(page);
+			goto out_unlock;
+		}
+		put_page(page);
+	}
+	if (reuse_swap_page(page, NULL)) {
 		pmd_t entry;
 		entry = pmd_mkyoung(orig_pmd);
 		entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma);
 		if (pmdp_set_access_flags(vma, haddr, vmf->pmd, entry,  1))
 			update_mmu_cache_pmd(vma, vmf->address, vmf->pmd);
 		ret |= VM_FAULT_WRITE;
+		unlock_page(page);
 		goto out_unlock;
 	}
+	unlock_page(page);
 	get_page(page);
 	spin_unlock(vmf->ptl);
 alloc:
@@ -1291,7 +1305,7 @@ alloc:
 	count_vm_event(THP_FAULT_ALLOC);
 
 	if (!page)
-		clear_huge_page(new_page, haddr, HPAGE_PMD_NR);
+		clear_huge_page(new_page, vmf->address, HPAGE_PMD_NR);
 	else
 		copy_user_huge_page(new_page, page, haddr, vma, HPAGE_PMD_NR);
 	__SetPageUptodate(new_page);
@@ -2467,6 +2481,9 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	VM_BUG_ON_PAGE(!PageCompound(page), page);
 
+	if (PageWriteback(page))
+		return -EBUSY;
+
 	if (PageAnon(head)) {
 		/*
 		 * The caller does not necessarily hold an mmap_sem that would
@@ -2544,7 +2561,12 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
 			__dec_node_page_state(page, NR_SHMEM_THPS);
 		spin_unlock(&pgdata->split_queue_lock);
 		__split_huge_page(page, list, flags);
-		ret = 0;
+		if (PageSwapCache(head)) {
+			swp_entry_t entry = { .val = page_private(head) };
+
+			ret = split_swap_cluster(entry);
+		} else
+			ret = 0;
 	} else {
 		if (IS_ENABLED(CONFIG_DEBUG_VM) && mapcount) {
 			pr_alert("total_mapcount: %u, page_count(): %u\n",
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 31e207cb399b..34625b257128 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1066,11 +1066,11 @@ static void free_gigantic_page(struct page *page, unsigned int order)
 }
 
 static int __alloc_gigantic_page(unsigned long start_pfn,
-				unsigned long nr_pages)
+				unsigned long nr_pages, gfp_t gfp_mask)
 {
 	unsigned long end_pfn = start_pfn + nr_pages;
 	return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE,
-				  GFP_KERNEL);
+				  gfp_mask);
 }
 
 static bool pfn_range_valid_gigantic(struct zone *z,
@@ -1108,19 +1108,24 @@ static bool zone_spans_last_pfn(const struct zone *zone,
 	return zone_spans_pfn(zone, last_pfn);
 }
 
-static struct page *alloc_gigantic_page(int nid, unsigned int order)
+static struct page *alloc_gigantic_page(int nid, struct hstate *h)
 {
+	unsigned int order = huge_page_order(h);
 	unsigned long nr_pages = 1 << order;
 	unsigned long ret, pfn, flags;
-	struct zone *z;
+	struct zonelist *zonelist;
+	struct zone *zone;
+	struct zoneref *z;
+	gfp_t gfp_mask;
 
-	z = NODE_DATA(nid)->node_zones;
-	for (; z - NODE_DATA(nid)->node_zones < MAX_NR_ZONES; z++) {
-		spin_lock_irqsave(&z->lock, flags);
+	gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE;
+	zonelist = node_zonelist(nid, gfp_mask);
+	for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), NULL) {
+		spin_lock_irqsave(&zone->lock, flags);
 
-		pfn = ALIGN(z->zone_start_pfn, nr_pages);
-		while (zone_spans_last_pfn(z, pfn, nr_pages)) {
-			if (pfn_range_valid_gigantic(z, pfn, nr_pages)) {
+		pfn = ALIGN(zone->zone_start_pfn, nr_pages);
+		while (zone_spans_last_pfn(zone, pfn, nr_pages)) {
+			if (pfn_range_valid_gigantic(zone, pfn, nr_pages)) {
 				/*
 				 * We release the zone lock here because
 				 * alloc_contig_range() will also lock the zone
@@ -1128,16 +1133,16 @@ static struct page *alloc_gigantic_page(int nid, unsigned int order)
 				 * spinning on this lock, it may win the race
 				 * and cause alloc_contig_range() to fail...
 				 */
-				spin_unlock_irqrestore(&z->lock, flags);
-				ret = __alloc_gigantic_page(pfn, nr_pages);
+				spin_unlock_irqrestore(&zone->lock, flags);
+				ret = __alloc_gigantic_page(pfn, nr_pages, gfp_mask);
 				if (!ret)
 					return pfn_to_page(pfn);
-				spin_lock_irqsave(&z->lock, flags);
+				spin_lock_irqsave(&zone->lock, flags);
 			}
 			pfn += nr_pages;
 		}
 
-		spin_unlock_irqrestore(&z->lock, flags);
+		spin_unlock_irqrestore(&zone->lock, flags);
 	}
 
 	return NULL;
@@ -1150,7 +1155,7 @@ static struct page *alloc_fresh_gigantic_page_node(struct hstate *h, int nid)
 {
 	struct page *page;
 
-	page = alloc_gigantic_page(nid, huge_page_order(h));
+	page = alloc_gigantic_page(nid, h);
 	if (page) {
 		prep_compound_gigantic_page(page, huge_page_order(h));
 		prep_new_huge_page(h, page, nid);
@@ -2569,13 +2574,13 @@ static struct attribute *hstate_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group hstate_attr_group = {
+static const struct attribute_group hstate_attr_group = {
 	.attrs = hstate_attrs,
 };
 
 static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent,
 				    struct kobject **hstate_kobjs,
-				    struct attribute_group *hstate_attr_group)
+				    const struct attribute_group *hstate_attr_group)
 {
 	int retval;
 	int hi = hstate_index(h);
@@ -2633,7 +2638,7 @@ static struct attribute *per_node_hstate_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group per_node_hstate_attr_group = {
+static const struct attribute_group per_node_hstate_attr_group = {
 	.attrs = per_node_hstate_attrs,
 };
 
@@ -4600,6 +4605,15 @@ pte_t *huge_pte_alloc(struct mm_struct *mm,
 	return pte;
 }
 
+/*
+ * huge_pte_offset() - Walk the page table to resolve the hugepage
+ * entry at address @addr
+ *
+ * Return: Pointer to page table or swap entry (PUD or PMD) for
+ * address @addr, or NULL if a p*d_none() entry is encountered and the
+ * size @sz doesn't match the hugepage size at this level of the page
+ * table.
+ */
 pte_t *huge_pte_offset(struct mm_struct *mm,
 		       unsigned long addr, unsigned long sz)
 {
@@ -4614,13 +4628,22 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
 	p4d = p4d_offset(pgd, addr);
 	if (!p4d_present(*p4d))
 		return NULL;
+
 	pud = pud_offset(p4d, addr);
-	if (!pud_present(*pud))
+	if (sz != PUD_SIZE && pud_none(*pud))
 		return NULL;
-	if (pud_huge(*pud))
+	/* hugepage or swap? */
+	if (pud_huge(*pud) || !pud_present(*pud))
 		return (pte_t *)pud;
+
 	pmd = pmd_offset(pud, addr);
-	return (pte_t *) pmd;
+	if (sz != PMD_SIZE && pmd_none(*pmd))
+		return NULL;
+	/* hugepage or swap? */
+	if (pmd_huge(*pmd) || !pmd_present(*pmd))
+		return (pte_t *)pmd;
+
+	return NULL;
 }
 
 #endif /* CONFIG_ARCH_WANT_GENERAL_HUGETLB */
diff --git a/mm/internal.h b/mm/internal.h
index 4ef49fc55e58..1df011f62480 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -480,6 +480,17 @@ unsigned long reclaim_clean_pages_from_list(struct zone *zone,
 /* Mask to get the watermark bits */
 #define ALLOC_WMARK_MASK	(ALLOC_NO_WATERMARKS-1)
 
+/*
+ * Only MMU archs have async oom victim reclaim - aka oom_reaper so we
+ * cannot assume a reduced access to memory reserves is sufficient for
+ * !MMU
+ */
+#ifdef CONFIG_MMU
+#define ALLOC_OOM		0x08
+#else
+#define ALLOC_OOM		ALLOC_NO_WATERMARKS
+#endif
+
 #define ALLOC_HARDER		0x10 /* try to alloc harder */
 #define ALLOC_HIGH		0x20 /* __GFP_HIGH set */
 #define ALLOC_CPUSET		0x40 /* check for correct cpuset */
@@ -525,4 +536,5 @@ static inline bool is_migrate_highatomic_page(struct page *page)
 	return get_pageblock_migratetype(page) == MIGRATE_HIGHATOMIC;
 }
 
+void setup_zone_pageset(struct zone *zone);
 #endif	/* __MM_INTERNAL_H */
diff --git a/mm/ksm.c b/mm/ksm.c
index db20f8436bc3..15dd7415f7b3 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -3043,7 +3043,7 @@ static struct attribute *ksm_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group ksm_attr_group = {
+static const struct attribute_group ksm_attr_group = {
 	.attrs = ksm_attrs,
 	.name = "ksm",
 };
diff --git a/mm/madvise.c b/mm/madvise.c
index 4d7d1e5ddba9..eea1c733286f 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -80,6 +80,17 @@ static long madvise_behavior(struct vm_area_struct *vma,
 		}
 		new_flags &= ~VM_DONTCOPY;
 		break;
+	case MADV_WIPEONFORK:
+		/* MADV_WIPEONFORK is only supported on anonymous memory. */
+		if (vma->vm_file || vma->vm_flags & VM_SHARED) {
+			error = -EINVAL;
+			goto out;
+		}
+		new_flags |= VM_WIPEONFORK;
+		break;
+	case MADV_KEEPONFORK:
+		new_flags &= ~VM_WIPEONFORK;
+		break;
 	case MADV_DONTDUMP:
 		new_flags |= VM_DONTDUMP;
 		break;
@@ -696,6 +707,8 @@ madvise_behavior_valid(int behavior)
 #endif
 	case MADV_DONTDUMP:
 	case MADV_DODUMP:
+	case MADV_WIPEONFORK:
+	case MADV_KEEPONFORK:
 #ifdef CONFIG_MEMORY_FAILURE
 	case MADV_SOFT_OFFLINE:
 	case MADV_HWPOISON:
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index e09741af816f..ad15850ee157 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -550,10 +550,12 @@ mem_cgroup_largest_soft_limit_node(struct mem_cgroup_tree_per_node *mctz)
  * value, and reading all cpu value can be performance bottleneck in some
  * common workload, threshold and synchronization as vmstat[] should be
  * implemented.
+ *
+ * The parameter idx can be of type enum memcg_event_item or vm_event_item.
  */
 
 static unsigned long memcg_sum_events(struct mem_cgroup *memcg,
-				      enum memcg_event_item event)
+				      int event)
 {
 	unsigned long val = 0;
 	int cpu;
@@ -1915,7 +1917,7 @@ retry:
 	 * bypass the last charges so that they can exit quickly and
 	 * free their memory.
 	 */
-	if (unlikely(test_thread_flag(TIF_MEMDIE) ||
+	if (unlikely(tsk_is_oom_victim(current) ||
 		     fatal_signal_pending(current) ||
 		     current->flags & PF_EXITING))
 		goto force;
@@ -4319,6 +4321,8 @@ static void mem_cgroup_css_offline(struct cgroup_subsys_state *css)
 	}
 	spin_unlock(&memcg->event_list_lock);
 
+	memcg->low = 0;
+
 	memcg_offline_kmem(memcg);
 	wb_memcg_offline(memcg);
 
@@ -4635,8 +4639,11 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
 		if (!ret || !target)
 			put_page(page);
 	}
-	/* There is a swap entry and a page doesn't exist or isn't charged */
-	if (ent.val && !ret &&
+	/*
+	 * There is a swap entry and a page doesn't exist or isn't charged.
+	 * But we cannot move a tail-page in a THP.
+	 */
+	if (ent.val && !ret && (!page || !PageTransCompound(page)) &&
 	    mem_cgroup_id(mc.from) == lookup_swap_cgroup_id(ent)) {
 		ret = MC_TARGET_SWAP;
 		if (target)
@@ -4647,8 +4654,8 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma,
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 /*
- * We don't consider swapping or file mapped pages because THP does not
- * support them for now.
+ * We don't consider PMD mapped swapping or file mapped pages because THP does
+ * not support them for now.
  * Caller should make sure that pmd_trans_huge(pmd) is true.
  */
 static enum mc_target_type get_mctgt_type_thp(struct vm_area_struct *vma,
@@ -5423,7 +5430,7 @@ int mem_cgroup_try_charge(struct page *page, struct mm_struct *mm,
 		 * in turn serializes uncharging.
 		 */
 		VM_BUG_ON_PAGE(!PageLocked(page), page);
-		if (page->mem_cgroup)
+		if (compound_head(page)->mem_cgroup)
 			goto out;
 
 		if (do_swap_account) {
@@ -5906,6 +5913,7 @@ static struct mem_cgroup *mem_cgroup_id_get_online(struct mem_cgroup *memcg)
 void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 {
 	struct mem_cgroup *memcg, *swap_memcg;
+	unsigned int nr_entries;
 	unsigned short oldid;
 
 	VM_BUG_ON_PAGE(PageLRU(page), page);
@@ -5926,19 +5934,24 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	 * ancestor for the swap instead and transfer the memory+swap charge.
 	 */
 	swap_memcg = mem_cgroup_id_get_online(memcg);
-	oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg), 1);
+	nr_entries = hpage_nr_pages(page);
+	/* Get references for the tail pages, too */
+	if (nr_entries > 1)
+		mem_cgroup_id_get_many(swap_memcg, nr_entries - 1);
+	oldid = swap_cgroup_record(entry, mem_cgroup_id(swap_memcg),
+				   nr_entries);
 	VM_BUG_ON_PAGE(oldid, page);
-	mem_cgroup_swap_statistics(swap_memcg, 1);
+	mem_cgroup_swap_statistics(swap_memcg, nr_entries);
 
 	page->mem_cgroup = NULL;
 
 	if (!mem_cgroup_is_root(memcg))
-		page_counter_uncharge(&memcg->memory, 1);
+		page_counter_uncharge(&memcg->memory, nr_entries);
 
 	if (memcg != swap_memcg) {
 		if (!mem_cgroup_is_root(swap_memcg))
-			page_counter_charge(&swap_memcg->memsw, 1);
-		page_counter_uncharge(&memcg->memsw, 1);
+			page_counter_charge(&swap_memcg->memsw, nr_entries);
+		page_counter_uncharge(&memcg->memsw, nr_entries);
 	}
 
 	/*
@@ -5948,7 +5961,8 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
 	 * only synchronisation we have for udpating the per-CPU variables.
 	 */
 	VM_BUG_ON(!irqs_disabled());
-	mem_cgroup_charge_statistics(memcg, page, false, -1);
+	mem_cgroup_charge_statistics(memcg, page, PageTransHuge(page),
+				     -nr_entries);
 	memcg_check_events(memcg, page);
 
 	if (!mem_cgroup_is_root(memcg))
diff --git a/mm/memory.c b/mm/memory.c
index 56e48e4593cb..13ee83b43878 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1513,8 +1513,20 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long start,
 	tlb_gather_mmu(&tlb, mm, start, end);
 	update_hiwater_rss(mm);
 	mmu_notifier_invalidate_range_start(mm, start, end);
-	for ( ; vma && vma->vm_start < end; vma = vma->vm_next)
+	for ( ; vma && vma->vm_start < end; vma = vma->vm_next) {
 		unmap_single_vma(&tlb, vma, start, end, NULL);
+
+		/*
+		 * zap_page_range does not specify whether mmap_sem should be
+		 * held for read or write. That allows parallel zap_page_range
+		 * operations to unmap a PTE and defer a flush meaning that
+		 * this call observes pte_none and fails to flush the TLB.
+		 * Rather than adding a complex API, ensure that no stale
+		 * TLB entries exist when this call returns.
+		 */
+		flush_tlb_range(vma, start, end);
+	}
+
 	mmu_notifier_invalidate_range_end(mm, start, end);
 	tlb_finish_mmu(&tlb, start, end);
 }
@@ -1676,7 +1688,7 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
 EXPORT_SYMBOL(vm_insert_page);
 
 static int insert_pfn(struct vm_area_struct *vma, unsigned long addr,
-			pfn_t pfn, pgprot_t prot)
+			pfn_t pfn, pgprot_t prot, bool mkwrite)
 {
 	struct mm_struct *mm = vma->vm_mm;
 	int retval;
@@ -1688,14 +1700,35 @@ static int insert_pfn(struct vm_area_struct *vma, unsigned long addr,
 	if (!pte)
 		goto out;
 	retval = -EBUSY;
-	if (!pte_none(*pte))
-		goto out_unlock;
+	if (!pte_none(*pte)) {
+		if (mkwrite) {
+			/*
+			 * For read faults on private mappings the PFN passed
+			 * in may not match the PFN we have mapped if the
+			 * mapped PFN is a writeable COW page.  In the mkwrite
+			 * case we are creating a writable PTE for a shared
+			 * mapping and we expect the PFNs to match.
+			 */
+			if (WARN_ON_ONCE(pte_pfn(*pte) != pfn_t_to_pfn(pfn)))
+				goto out_unlock;
+			entry = *pte;
+			goto out_mkwrite;
+		} else
+			goto out_unlock;
+	}
 
 	/* Ok, finally just insert the thing.. */
 	if (pfn_t_devmap(pfn))
 		entry = pte_mkdevmap(pfn_t_pte(pfn, prot));
 	else
 		entry = pte_mkspecial(pfn_t_pte(pfn, prot));
+
+out_mkwrite:
+	if (mkwrite) {
+		entry = pte_mkyoung(entry);
+		entry = maybe_mkwrite(pte_mkdirty(entry), vma);
+	}
+
 	set_pte_at(mm, addr, pte, entry);
 	update_mmu_cache(vma, addr, pte); /* XXX: why not for insert_page? */
 
@@ -1766,14 +1799,15 @@ int vm_insert_pfn_prot(struct vm_area_struct *vma, unsigned long addr,
 
 	track_pfn_insert(vma, &pgprot, __pfn_to_pfn_t(pfn, PFN_DEV));
 
-	ret = insert_pfn(vma, addr, __pfn_to_pfn_t(pfn, PFN_DEV), pgprot);
+	ret = insert_pfn(vma, addr, __pfn_to_pfn_t(pfn, PFN_DEV), pgprot,
+			false);
 
 	return ret;
 }
 EXPORT_SYMBOL(vm_insert_pfn_prot);
 
-int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
-			pfn_t pfn)
+static int __vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
+			pfn_t pfn, bool mkwrite)
 {
 	pgprot_t pgprot = vma->vm_page_prot;
 
@@ -1802,10 +1836,24 @@ int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
 		page = pfn_to_page(pfn_t_to_pfn(pfn));
 		return insert_page(vma, addr, page, pgprot);
 	}
-	return insert_pfn(vma, addr, pfn, pgprot);
+	return insert_pfn(vma, addr, pfn, pgprot, mkwrite);
+}
+
+int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
+			pfn_t pfn)
+{
+	return __vm_insert_mixed(vma, addr, pfn, false);
+
 }
 EXPORT_SYMBOL(vm_insert_mixed);
 
+int vm_insert_mixed_mkwrite(struct vm_area_struct *vma, unsigned long addr,
+			pfn_t pfn)
+{
+	return __vm_insert_mixed(vma, addr, pfn, true);
+}
+EXPORT_SYMBOL(vm_insert_mixed_mkwrite);
+
 /*
  * maps a range of physical memory into the requested pages. the old
  * mappings are removed. any references to nonexistent pages results
@@ -2571,7 +2619,7 @@ static int do_wp_page(struct vm_fault *vmf)
 	 * not dirty accountable.
 	 */
 	if (PageAnon(vmf->page) && !PageKsm(vmf->page)) {
-		int total_mapcount;
+		int total_map_swapcount;
 		if (!trylock_page(vmf->page)) {
 			get_page(vmf->page);
 			pte_unmap_unlock(vmf->pte, vmf->ptl);
@@ -2586,8 +2634,8 @@ static int do_wp_page(struct vm_fault *vmf)
 			}
 			put_page(vmf->page);
 		}
-		if (reuse_swap_page(vmf->page, &total_mapcount)) {
-			if (total_mapcount == 1) {
+		if (reuse_swap_page(vmf->page, &total_map_swapcount)) {
+			if (total_map_swapcount == 1) {
 				/*
 				 * The page is all ours. Move it to
 				 * our anon_vma so the rmap code will
@@ -2704,16 +2752,23 @@ EXPORT_SYMBOL(unmap_mapping_range);
 int do_swap_page(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
-	struct page *page, *swapcache;
+	struct page *page = NULL, *swapcache;
 	struct mem_cgroup *memcg;
+	struct vma_swap_readahead swap_ra;
 	swp_entry_t entry;
 	pte_t pte;
 	int locked;
 	int exclusive = 0;
 	int ret = 0;
+	bool vma_readahead = swap_use_vma_readahead();
 
-	if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte))
+	if (vma_readahead)
+		page = swap_readahead_detect(vmf, &swap_ra);
+	if (!pte_unmap_same(vma->vm_mm, vmf->pmd, vmf->pte, vmf->orig_pte)) {
+		if (page)
+			put_page(page);
 		goto out;
+	}
 
 	entry = pte_to_swp_entry(vmf->orig_pte);
 	if (unlikely(non_swap_entry(entry))) {
@@ -2729,10 +2784,16 @@ int do_swap_page(struct vm_fault *vmf)
 		goto out;
 	}
 	delayacct_set_flag(DELAYACCT_PF_SWAPIN);
-	page = lookup_swap_cache(entry);
+	if (!page)
+		page = lookup_swap_cache(entry, vma_readahead ? vma : NULL,
+					 vmf->address);
 	if (!page) {
-		page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE, vma,
-					vmf->address);
+		if (vma_readahead)
+			page = do_swap_page_readahead(entry,
+				GFP_HIGHUSER_MOVABLE, vmf, &swap_ra);
+		else
+			page = swapin_readahead(entry,
+				GFP_HIGHUSER_MOVABLE, vma, vmf->address);
 		if (!page) {
 			/*
 			 * Back out if somebody else faulted in this pte
@@ -4356,19 +4417,53 @@ static void clear_gigantic_page(struct page *page,
 	}
 }
 void clear_huge_page(struct page *page,
-		     unsigned long addr, unsigned int pages_per_huge_page)
+		     unsigned long addr_hint, unsigned int pages_per_huge_page)
 {
-	int i;
+	int i, n, base, l;
+	unsigned long addr = addr_hint &
+		~(((unsigned long)pages_per_huge_page << PAGE_SHIFT) - 1);
 
 	if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) {
 		clear_gigantic_page(page, addr, pages_per_huge_page);
 		return;
 	}
 
+	/* Clear sub-page to access last to keep its cache lines hot */
 	might_sleep();
-	for (i = 0; i < pages_per_huge_page; i++) {
+	n = (addr_hint - addr) / PAGE_SIZE;
+	if (2 * n <= pages_per_huge_page) {
+		/* If sub-page to access in first half of huge page */
+		base = 0;
+		l = n;
+		/* Clear sub-pages at the end of huge page */
+		for (i = pages_per_huge_page - 1; i >= 2 * n; i--) {
+			cond_resched();
+			clear_user_highpage(page + i, addr + i * PAGE_SIZE);
+		}
+	} else {
+		/* If sub-page to access in second half of huge page */
+		base = pages_per_huge_page - 2 * (pages_per_huge_page - n);
+		l = pages_per_huge_page - n;
+		/* Clear sub-pages at the begin of huge page */
+		for (i = 0; i < base; i++) {
+			cond_resched();
+			clear_user_highpage(page + i, addr + i * PAGE_SIZE);
+		}
+	}
+	/*
+	 * Clear remaining sub-pages in left-right-left-right pattern
+	 * towards the sub-page to access
+	 */
+	for (i = 0; i < l; i++) {
+		int left_idx = base + i;
+		int right_idx = base + 2 * l - 1 - i;
+
+		cond_resched();
+		clear_user_highpage(page + left_idx,
+				    addr + left_idx * PAGE_SIZE);
 		cond_resched();
-		clear_user_highpage(page + i, addr + i * PAGE_SIZE);
+		clear_user_highpage(page + right_idx,
+				    addr + right_idx * PAGE_SIZE);
 	}
 }
 
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 8dccc317aac2..73bf17df6899 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -773,31 +773,6 @@ static void node_states_set_node(int node, struct memory_notify *arg)
 	node_set_state(node, N_MEMORY);
 }
 
-bool allow_online_pfn_range(int nid, unsigned long pfn, unsigned long nr_pages, int online_type)
-{
-	struct pglist_data *pgdat = NODE_DATA(nid);
-	struct zone *movable_zone = &pgdat->node_zones[ZONE_MOVABLE];
-	struct zone *default_zone = default_zone_for_pfn(nid, pfn, nr_pages);
-
-	/*
-	 * TODO there shouldn't be any inherent reason to have ZONE_NORMAL
-	 * physically before ZONE_MOVABLE. All we need is they do not
-	 * overlap. Historically we didn't allow ZONE_NORMAL after ZONE_MOVABLE
-	 * though so let's stick with it for simplicity for now.
-	 * TODO make sure we do not overlap with ZONE_DEVICE
-	 */
-	if (online_type == MMOP_ONLINE_KERNEL) {
-		if (zone_is_empty(movable_zone))
-			return true;
-		return movable_zone->zone_start_pfn >= pfn + nr_pages;
-	} else if (online_type == MMOP_ONLINE_MOVABLE) {
-		return zone_end_pfn(default_zone) <= pfn;
-	}
-
-	/* MMOP_ONLINE_KEEP will always succeed and inherits the current zone */
-	return online_type == MMOP_ONLINE_KEEP;
-}
-
 static void __meminit resize_zone_range(struct zone *zone, unsigned long start_pfn,
 		unsigned long nr_pages)
 {
@@ -856,7 +831,7 @@ void __ref move_pfn_range_to_zone(struct zone *zone,
  * If no kernel zone covers this pfn range it will automatically go
  * to the ZONE_NORMAL.
  */
-struct zone *default_zone_for_pfn(int nid, unsigned long start_pfn,
+static struct zone *default_kernel_zone_for_pfn(int nid, unsigned long start_pfn,
 		unsigned long nr_pages)
 {
 	struct pglist_data *pgdat = NODE_DATA(nid);
@@ -872,17 +847,40 @@ struct zone *default_zone_for_pfn(int nid, unsigned long start_pfn,
 	return &pgdat->node_zones[ZONE_NORMAL];
 }
 
-static inline bool movable_pfn_range(int nid, struct zone *default_zone,
-		unsigned long start_pfn, unsigned long nr_pages)
+static inline struct zone *default_zone_for_pfn(int nid, unsigned long start_pfn,
+		unsigned long nr_pages)
 {
-	if (!allow_online_pfn_range(nid, start_pfn, nr_pages,
-				MMOP_ONLINE_KERNEL))
-		return true;
+	struct zone *kernel_zone = default_kernel_zone_for_pfn(nid, start_pfn,
+			nr_pages);
+	struct zone *movable_zone = &NODE_DATA(nid)->node_zones[ZONE_MOVABLE];
+	bool in_kernel = zone_intersects(kernel_zone, start_pfn, nr_pages);
+	bool in_movable = zone_intersects(movable_zone, start_pfn, nr_pages);
 
-	if (!movable_node_is_enabled())
-		return false;
+	/*
+	 * We inherit the existing zone in a simple case where zones do not
+	 * overlap in the given range
+	 */
+	if (in_kernel ^ in_movable)
+		return (in_kernel) ? kernel_zone : movable_zone;
 
-	return !zone_intersects(default_zone, start_pfn, nr_pages);
+	/*
+	 * If the range doesn't belong to any zone or two zones overlap in the
+	 * given range then we use movable zone only if movable_node is
+	 * enabled because we always online to a kernel zone by default.
+	 */
+	return movable_node_enabled ? movable_zone : kernel_zone;
+}
+
+struct zone * zone_for_pfn_range(int online_type, int nid, unsigned start_pfn,
+		unsigned long nr_pages)
+{
+	if (online_type == MMOP_ONLINE_KERNEL)
+		return default_kernel_zone_for_pfn(nid, start_pfn, nr_pages);
+
+	if (online_type == MMOP_ONLINE_MOVABLE)
+		return &NODE_DATA(nid)->node_zones[ZONE_MOVABLE];
+
+	return default_zone_for_pfn(nid, start_pfn, nr_pages);
 }
 
 /*
@@ -892,28 +890,14 @@ static inline bool movable_pfn_range(int nid, struct zone *default_zone,
 static struct zone * __meminit move_pfn_range(int online_type, int nid,
 		unsigned long start_pfn, unsigned long nr_pages)
 {
-	struct pglist_data *pgdat = NODE_DATA(nid);
-	struct zone *zone = default_zone_for_pfn(nid, start_pfn, nr_pages);
-
-	if (online_type == MMOP_ONLINE_KEEP) {
-		struct zone *movable_zone = &pgdat->node_zones[ZONE_MOVABLE];
-		/*
-		 * MMOP_ONLINE_KEEP defaults to MMOP_ONLINE_KERNEL but use
-		 * movable zone if that is not possible (e.g. we are within
-		 * or past the existing movable zone). movable_node overrides
-		 * this default and defaults to movable zone
-		 */
-		if (movable_pfn_range(nid, zone, start_pfn, nr_pages))
-			zone = movable_zone;
-	} else if (online_type == MMOP_ONLINE_MOVABLE) {
-		zone = &pgdat->node_zones[ZONE_MOVABLE];
-	}
+	struct zone *zone;
 
+	zone = zone_for_pfn_range(online_type, nid, start_pfn, nr_pages);
 	move_pfn_range_to_zone(zone, start_pfn, nr_pages);
 	return zone;
 }
 
-/* Must be protected by mem_hotplug_begin() */
+/* Must be protected by mem_hotplug_begin() or a device_lock */
 int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_type)
 {
 	unsigned long flags;
@@ -925,9 +909,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
 	struct memory_notify arg;
 
 	nid = pfn_to_nid(pfn);
-	if (!allow_online_pfn_range(nid, pfn, nr_pages, online_type))
-		return -EINVAL;
-
 	/* associate pfn range with the zone */
 	zone = move_pfn_range(online_type, nid, pfn, nr_pages);
 
@@ -945,10 +926,9 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
 	 * This means the page allocator ignores this zone.
 	 * So, zonelist must be updated after online.
 	 */
-	mutex_lock(&zonelists_mutex);
 	if (!populated_zone(zone)) {
 		need_zonelists_rebuild = 1;
-		build_all_zonelists(NULL, zone);
+		setup_zone_pageset(zone);
 	}
 
 	ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
@@ -956,7 +936,6 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
 	if (ret) {
 		if (need_zonelists_rebuild)
 			zone_pcp_reset(zone);
-		mutex_unlock(&zonelists_mutex);
 		goto failed_addition;
 	}
 
@@ -969,13 +948,11 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ
 	if (onlined_pages) {
 		node_states_set_node(nid, &arg);
 		if (need_zonelists_rebuild)
-			build_all_zonelists(NULL, NULL);
+			build_all_zonelists(NULL);
 		else
 			zone_pcp_update(zone);
 	}
 
-	mutex_unlock(&zonelists_mutex);
-
 	init_per_zone_wmark_min();
 
 	if (onlined_pages) {
@@ -1046,9 +1023,7 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
 	 * The node we allocated has no zone fallback lists. For avoiding
 	 * to access not-initialized zonelist, build here.
 	 */
-	mutex_lock(&zonelists_mutex);
-	build_all_zonelists(pgdat, NULL);
-	mutex_unlock(&zonelists_mutex);
+	build_all_zonelists(pgdat);
 
 	/*
 	 * zone->managed_pages is set to an approximate value in
@@ -1100,13 +1075,6 @@ int try_online_node(int nid)
 	node_set_online(nid);
 	ret = register_one_node(nid);
 	BUG_ON(ret);
-
-	if (pgdat->node_zonelists->_zonerefs->zone == NULL) {
-		mutex_lock(&zonelists_mutex);
-		build_all_zonelists(NULL, NULL);
-		mutex_unlock(&zonelists_mutex);
-	}
-
 out:
 	mem_hotplug_done();
 	return ret;
@@ -1722,9 +1690,7 @@ repeat:
 
 	if (!populated_zone(zone)) {
 		zone_pcp_reset(zone);
-		mutex_lock(&zonelists_mutex);
-		build_all_zonelists(NULL, NULL);
-		mutex_unlock(&zonelists_mutex);
+		build_all_zonelists(NULL);
 	} else
 		zone_pcp_update(zone);
 
@@ -1750,7 +1716,7 @@ failed_removal:
 	return ret;
 }
 
-/* Must be protected by mem_hotplug_begin() */
+/* Must be protected by mem_hotplug_begin() or a device_lock */
 int offline_pages(unsigned long start_pfn, unsigned long nr_pages)
 {
 	return __offline_pages(start_pfn, start_pfn + nr_pages, 120 * HZ);
diff --git a/mm/mmap.c b/mm/mmap.c
index f19efcf75418..4c5981651407 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -44,6 +44,7 @@
 #include <linux/userfaultfd_k.h>
 #include <linux/moduleparam.h>
 #include <linux/pkeys.h>
+#include <linux/oom.h>
 
 #include <linux/uaccess.h>
 #include <asm/cacheflush.h>
@@ -2639,13 +2640,6 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
 	if (vma->vm_start >= end)
 		return 0;
 
-	if (uf) {
-		int error = userfaultfd_unmap_prep(vma, start, end, uf);
-
-		if (error)
-			return error;
-	}
-
 	/*
 	 * If we need to split any vma, do it now to save pain later.
 	 *
@@ -2679,6 +2673,21 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len,
 	}
 	vma = prev ? prev->vm_next : mm->mmap;
 
+	if (unlikely(uf)) {
+		/*
+		 * If userfaultfd_unmap_prep returns an error the vmas
+		 * will remain splitted, but userland will get a
+		 * highly unexpected error anyway. This is no
+		 * different than the case where the first of the two
+		 * __split_vma fails, but we don't undo the first
+		 * split, despite we could. This is unlikely enough
+		 * failure that it's not worth optimizing it for.
+		 */
+		int error = userfaultfd_unmap_prep(vma, start, end, uf);
+		if (error)
+			return error;
+	}
+
 	/*
 	 * unlock any mlock()ed ranges before detaching vmas
 	 */
@@ -2993,6 +3002,23 @@ void exit_mmap(struct mm_struct *mm)
 	/* Use -1 here to ensure all VMAs in the mm are unmapped */
 	unmap_vmas(&tlb, vma, 0, -1);
 
+	set_bit(MMF_OOM_SKIP, &mm->flags);
+	if (unlikely(tsk_is_oom_victim(current))) {
+		/*
+		 * Wait for oom_reap_task() to stop working on this
+		 * mm. Because MMF_OOM_SKIP is already set before
+		 * calling down_read(), oom_reap_task() will not run
+		 * on this "mm" post up_write().
+		 *
+		 * tsk_is_oom_victim() cannot be set from under us
+		 * either because current->mm is already set to NULL
+		 * under task_lock before calling mmput and oom_mm is
+		 * set not NULL by the OOM killer only if current->mm
+		 * is found not NULL while holding the task_lock.
+		 */
+		down_write(&mm->mmap_sem);
+		up_write(&mm->mmap_sem);
+	}
 	free_pgtables(&tlb, vma, FIRST_USER_ADDRESS, USER_PGTABLES_CEILING);
 	tlb_finish_mmu(&tlb, 0, -1);
 
@@ -3514,7 +3540,7 @@ static int init_user_reserve(void)
 {
 	unsigned long free_kbytes;
 
-	free_kbytes = global_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
+	free_kbytes = global_zone_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
 
 	sysctl_user_reserve_kbytes = min(free_kbytes / 32, 1UL << 17);
 	return 0;
@@ -3535,7 +3561,7 @@ static int init_admin_reserve(void)
 {
 	unsigned long free_kbytes;
 
-	free_kbytes = global_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
+	free_kbytes = global_zone_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
 
 	sysctl_admin_reserve_kbytes = min(free_kbytes / 32, 1UL << 13);
 	return 0;
@@ -3579,7 +3605,7 @@ static int reserve_mem_notifier(struct notifier_block *nb,
 
 		break;
 	case MEM_OFFLINE:
-		free_kbytes = global_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
+		free_kbytes = global_zone_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
 
 		if (sysctl_user_reserve_kbytes > free_kbytes) {
 			init_user_reserve();
diff --git a/mm/mremap.c b/mm/mremap.c
index 3f23715d3c69..7395564daa6c 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -384,6 +384,19 @@ static struct vm_area_struct *vma_to_resize(unsigned long addr,
 	if (!vma || vma->vm_start > addr)
 		return ERR_PTR(-EFAULT);
 
+	/*
+	 * !old_len is a special case where an attempt is made to 'duplicate'
+	 * a mapping.  This makes no sense for private mappings as it will
+	 * instead create a fresh/new mapping unrelated to the original.  This
+	 * is contrary to the basic idea of mremap which creates new mappings
+	 * based on the original.  There are no known use cases for this
+	 * behavior.  As a result, fail such attempts.
+	 */
+	if (!old_len && !(vma->vm_flags & (VM_SHARED | VM_MAYSHARE))) {
+		pr_warn_once("%s (%d): attempted to duplicate a private mapping with mremap.  This is not supported.\n", current->comm, current->pid);
+		return ERR_PTR(-EINVAL);
+	}
+
 	if (is_vm_hugetlb_page(vma))
 		return ERR_PTR(-EINVAL);
 
diff --git a/mm/nommu.c b/mm/nommu.c
index fc184f597d59..53d5175a5c14 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1962,7 +1962,7 @@ static int __meminit init_user_reserve(void)
 {
 	unsigned long free_kbytes;
 
-	free_kbytes = global_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
+	free_kbytes = global_zone_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
 
 	sysctl_user_reserve_kbytes = min(free_kbytes / 32, 1UL << 17);
 	return 0;
@@ -1983,7 +1983,7 @@ static int __meminit init_admin_reserve(void)
 {
 	unsigned long free_kbytes;
 
-	free_kbytes = global_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
+	free_kbytes = global_zone_page_state(NR_FREE_PAGES) << (PAGE_SHIFT - 10);
 
 	sysctl_admin_reserve_kbytes = min(free_kbytes / 32, 1UL << 13);
 	return 0;
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 9e8b4f030c1c..99736e026712 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -495,11 +495,12 @@ static bool __oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm)
 	}
 
 	/*
-	 * increase mm_users only after we know we will reap something so
-	 * that the mmput_async is called only when we have reaped something
-	 * and delayed __mmput doesn't matter that much
+	 * MMF_OOM_SKIP is set by exit_mmap when the OOM reaper can't
+	 * work on the mm anymore. The check for MMF_OOM_SKIP must run
+	 * under mmap_sem for reading because it serializes against the
+	 * down_write();up_write() cycle in exit_mmap().
 	 */
-	if (!mmget_not_zero(mm)) {
+	if (test_bit(MMF_OOM_SKIP, &mm->flags)) {
 		up_read(&mm->mmap_sem);
 		trace_skip_task_reaping(tsk->pid);
 		goto unlock_oom;
@@ -542,12 +543,6 @@ static bool __oom_reap_task_mm(struct task_struct *tsk, struct mm_struct *mm)
 			K(get_mm_counter(mm, MM_SHMEMPAGES)));
 	up_read(&mm->mmap_sem);
 
-	/*
-	 * Drop our reference but make sure the mmput slow path is called from a
-	 * different context because we shouldn't risk we get stuck there and
-	 * put the oom_reaper out of the way.
-	 */
-	mmput_async(mm);
 	trace_finish_task_reaping(tsk->pid);
 unlock_oom:
 	mutex_unlock(&oom_lock);
@@ -824,7 +819,8 @@ static void oom_kill_process(struct oom_control *oc, const char *message)
 
 	/*
 	 * If the task is already exiting, don't alarm the sysadmin or kill
-	 * its children or threads, just set TIF_MEMDIE so it can die quickly
+	 * its children or threads, just give it access to memory reserves
+	 * so it can die quickly
 	 */
 	task_lock(p);
 	if (task_will_free_mem(p)) {
@@ -889,9 +885,9 @@ static void oom_kill_process(struct oom_control *oc, const char *message)
 	count_memcg_event_mm(mm, OOM_KILL);
 
 	/*
-	 * We should send SIGKILL before setting TIF_MEMDIE in order to prevent
-	 * the OOM victim from depleting the memory reserves from the user
-	 * space under its control.
+	 * We should send SIGKILL before granting access to memory reserves
+	 * in order to prevent the OOM victim from depleting the memory
+	 * reserves from the user space under its control.
 	 */
 	do_send_sig_info(SIGKILL, SEND_SIG_FORCED, victim, true);
 	mark_oom_victim(victim);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index bf050ab025b7..0b9c5cbe8eba 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -363,7 +363,7 @@ static unsigned long global_dirtyable_memory(void)
 {
 	unsigned long x;
 
-	x = global_page_state(NR_FREE_PAGES);
+	x = global_zone_page_state(NR_FREE_PAGES);
 	/*
 	 * Pages reserved for the kernel should not be considered
 	 * dirtyable, to prevent a situation where reclaim has to
@@ -1405,7 +1405,7 @@ void wb_update_bandwidth(struct bdi_writeback *wb, unsigned long start_time)
  * will look to see if it needs to start dirty throttling.
  *
  * If dirty_poll_interval is too low, big NUMA machines will call the expensive
- * global_page_state() too often. So scale it near-sqrt to the safety margin
+ * global_zone_page_state() too often. So scale it near-sqrt to the safety margin
  * (the number of pages we may dirty without exceeding the dirty limits).
  */
 static unsigned long dirty_poll_interval(unsigned long dirty,
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 9327a940e373..a9add06fe768 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2951,7 +2951,7 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
 {
 	long min = mark;
 	int o;
-	const bool alloc_harder = (alloc_flags & ALLOC_HARDER);
+	const bool alloc_harder = (alloc_flags & (ALLOC_HARDER|ALLOC_OOM));
 
 	/* free_pages may go negative - that's OK */
 	free_pages -= (1 << order) - 1;
@@ -2964,10 +2964,21 @@ bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
 	 * the high-atomic reserves. This will over-estimate the size of the
 	 * atomic reserve but it avoids a search.
 	 */
-	if (likely(!alloc_harder))
+	if (likely(!alloc_harder)) {
 		free_pages -= z->nr_reserved_highatomic;
-	else
-		min -= min / 4;
+	} else {
+		/*
+		 * OOM victims can try even harder than normal ALLOC_HARDER
+		 * users on the grounds that it's definitely going to be in
+		 * the exit path shortly and free memory. Any allocation it
+		 * makes during the free path will be small and short-lived.
+		 */
+		if (alloc_flags & ALLOC_OOM)
+			min -= min / 2;
+		else
+			min -= min / 4;
+	}
+
 
 #ifdef CONFIG_CMA
 	/* If allocation can't use CMA areas don't use free CMA pages */
@@ -3205,7 +3216,7 @@ static void warn_alloc_show_mem(gfp_t gfp_mask, nodemask_t *nodemask)
 	 * of allowed nodes.
 	 */
 	if (!(gfp_mask & __GFP_NOMEMALLOC))
-		if (test_thread_flag(TIF_MEMDIE) ||
+		if (tsk_is_oom_victim(current) ||
 		    (current->flags & (PF_MEMALLOC | PF_EXITING)))
 			filter &= ~SHOW_MEM_FILTER_NODES;
 	if (in_interrupt() || !(gfp_mask & __GFP_DIRECT_RECLAIM))
@@ -3668,21 +3679,46 @@ gfp_to_alloc_flags(gfp_t gfp_mask)
 	return alloc_flags;
 }
 
-bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
+static bool oom_reserves_allowed(struct task_struct *tsk)
 {
-	if (unlikely(gfp_mask & __GFP_NOMEMALLOC))
+	if (!tsk_is_oom_victim(tsk))
 		return false;
 
+	/*
+	 * !MMU doesn't have oom reaper so give access to memory reserves
+	 * only to the thread with TIF_MEMDIE set
+	 */
+	if (!IS_ENABLED(CONFIG_MMU) && !test_thread_flag(TIF_MEMDIE))
+		return false;
+
+	return true;
+}
+
+/*
+ * Distinguish requests which really need access to full memory
+ * reserves from oom victims which can live with a portion of it
+ */
+static inline int __gfp_pfmemalloc_flags(gfp_t gfp_mask)
+{
+	if (unlikely(gfp_mask & __GFP_NOMEMALLOC))
+		return 0;
 	if (gfp_mask & __GFP_MEMALLOC)
-		return true;
+		return ALLOC_NO_WATERMARKS;
 	if (in_serving_softirq() && (current->flags & PF_MEMALLOC))
-		return true;
-	if (!in_interrupt() &&
-			((current->flags & PF_MEMALLOC) ||
-			 unlikely(test_thread_flag(TIF_MEMDIE))))
-		return true;
+		return ALLOC_NO_WATERMARKS;
+	if (!in_interrupt()) {
+		if (current->flags & PF_MEMALLOC)
+			return ALLOC_NO_WATERMARKS;
+		else if (oom_reserves_allowed(current))
+			return ALLOC_OOM;
+	}
 
-	return false;
+	return 0;
+}
+
+bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
+{
+	return !!__gfp_pfmemalloc_flags(gfp_mask);
 }
 
 /*
@@ -3835,6 +3871,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
 	unsigned long alloc_start = jiffies;
 	unsigned int stall_timeout = 10 * HZ;
 	unsigned int cpuset_mems_cookie;
+	int reserve_flags;
 
 	/*
 	 * In the slowpath, we sanity check order to avoid ever trying to
@@ -3940,15 +3977,16 @@ retry:
 	if (gfp_mask & __GFP_KSWAPD_RECLAIM)
 		wake_all_kswapds(order, ac);
 
-	if (gfp_pfmemalloc_allowed(gfp_mask))
-		alloc_flags = ALLOC_NO_WATERMARKS;
+	reserve_flags = __gfp_pfmemalloc_flags(gfp_mask);
+	if (reserve_flags)
+		alloc_flags = reserve_flags;
 
 	/*
 	 * Reset the zonelist iterators if memory policies can be ignored.
 	 * These allocations are high priority and system rather than user
 	 * orientated.
 	 */
-	if (!(alloc_flags & ALLOC_CPUSET) || (alloc_flags & ALLOC_NO_WATERMARKS)) {
+	if (!(alloc_flags & ALLOC_CPUSET) || reserve_flags) {
 		ac->zonelist = node_zonelist(numa_node_id(), gfp_mask);
 		ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
 					ac->high_zoneidx, ac->nodemask);
@@ -4025,8 +4063,8 @@ retry:
 		goto got_pg;
 
 	/* Avoid allocations with no watermarks from looping endlessly */
-	if (test_thread_flag(TIF_MEMDIE) &&
-	    (alloc_flags == ALLOC_NO_WATERMARKS ||
+	if (tsk_is_oom_victim(current) &&
+	    (alloc_flags == ALLOC_OOM ||
 	     (gfp_mask & __GFP_NOMEMALLOC)))
 		goto nopage;
 
@@ -4509,7 +4547,7 @@ long si_mem_available(void)
 	 * Estimate the amount of memory available for userspace allocations,
 	 * without causing swapping.
 	 */
-	available = global_page_state(NR_FREE_PAGES) - totalreserve_pages;
+	available = global_zone_page_state(NR_FREE_PAGES) - totalreserve_pages;
 
 	/*
 	 * Not all the page cache can be freed, otherwise the system will
@@ -4538,7 +4576,7 @@ void si_meminfo(struct sysinfo *val)
 {
 	val->totalram = totalram_pages;
 	val->sharedram = global_node_page_state(NR_SHMEM);
-	val->freeram = global_page_state(NR_FREE_PAGES);
+	val->freeram = global_zone_page_state(NR_FREE_PAGES);
 	val->bufferram = nr_blockdev_pages();
 	val->totalhigh = totalhigh_pages;
 	val->freehigh = nr_free_highpages();
@@ -4673,11 +4711,11 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 		global_node_page_state(NR_SLAB_UNRECLAIMABLE),
 		global_node_page_state(NR_FILE_MAPPED),
 		global_node_page_state(NR_SHMEM),
-		global_page_state(NR_PAGETABLE),
-		global_page_state(NR_BOUNCE),
-		global_page_state(NR_FREE_PAGES),
+		global_zone_page_state(NR_PAGETABLE),
+		global_zone_page_state(NR_BOUNCE),
+		global_zone_page_state(NR_FREE_PAGES),
 		free_pcp,
-		global_page_state(NR_FREE_CMA_PAGES));
+		global_zone_page_state(NR_FREE_CMA_PAGES));
 
 	for_each_online_pgdat(pgdat) {
 		if (show_mem_node_skip(filter, pgdat->node_id, nodemask))
@@ -4839,18 +4877,17 @@ static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
  *
  * Add all populated zones of a node to the zonelist.
  */
-static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
-				int nr_zones)
+static int build_zonerefs_node(pg_data_t *pgdat, struct zoneref *zonerefs)
 {
 	struct zone *zone;
 	enum zone_type zone_type = MAX_NR_ZONES;
+	int nr_zones = 0;
 
 	do {
 		zone_type--;
 		zone = pgdat->node_zones + zone_type;
 		if (managed_zone(zone)) {
-			zoneref_set_zone(zone,
-				&zonelist->_zonerefs[nr_zones++]);
+			zoneref_set_zone(zone, &zonerefs[nr_zones++]);
 			check_highest_zone(zone_type);
 		}
 	} while (zone_type);
@@ -4858,52 +4895,18 @@ static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
 	return nr_zones;
 }
 
-
-/*
- *  zonelist_order:
- *  0 = automatic detection of better ordering.
- *  1 = order by ([node] distance, -zonetype)
- *  2 = order by (-zonetype, [node] distance)
- *
- *  If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
- *  the same zonelist. So only NUMA can configure this param.
- */
-#define ZONELIST_ORDER_DEFAULT  0
-#define ZONELIST_ORDER_NODE     1
-#define ZONELIST_ORDER_ZONE     2
-
-/* zonelist order in the kernel.
- * set_zonelist_order() will set this to NODE or ZONE.
- */
-static int current_zonelist_order = ZONELIST_ORDER_DEFAULT;
-static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"};
-
-
 #ifdef CONFIG_NUMA
-/* The value user specified ....changed by config */
-static int user_zonelist_order = ZONELIST_ORDER_DEFAULT;
-/* string for sysctl */
-#define NUMA_ZONELIST_ORDER_LEN	16
-char numa_zonelist_order[16] = "default";
-
-/*
- * interface for configure zonelist ordering.
- * command line option "numa_zonelist_order"
- *	= "[dD]efault	- default, automatic configuration.
- *	= "[nN]ode 	- order by node locality, then by zone within node
- *	= "[zZ]one      - order by zone, then by locality within zone
- */
 
 static int __parse_numa_zonelist_order(char *s)
 {
-	if (*s == 'd' || *s == 'D') {
-		user_zonelist_order = ZONELIST_ORDER_DEFAULT;
-	} else if (*s == 'n' || *s == 'N') {
-		user_zonelist_order = ZONELIST_ORDER_NODE;
-	} else if (*s == 'z' || *s == 'Z') {
-		user_zonelist_order = ZONELIST_ORDER_ZONE;
-	} else {
-		pr_warn("Ignoring invalid numa_zonelist_order value:  %s\n", s);
+	/*
+	 * We used to support different zonlists modes but they turned
+	 * out to be just not useful. Let's keep the warning in place
+	 * if somebody still use the cmd line parameter so that we do
+	 * not fail it silently
+	 */
+	if (!(*s == 'd' || *s == 'D' || *s == 'n' || *s == 'N')) {
+		pr_warn("Ignoring unsupported numa_zonelist_order value:  %s\n", s);
 		return -EINVAL;
 	}
 	return 0;
@@ -4911,19 +4914,15 @@ static int __parse_numa_zonelist_order(char *s)
 
 static __init int setup_numa_zonelist_order(char *s)
 {
-	int ret;
-
 	if (!s)
 		return 0;
 
-	ret = __parse_numa_zonelist_order(s);
-	if (ret == 0)
-		strlcpy(numa_zonelist_order, s, NUMA_ZONELIST_ORDER_LEN);
-
-	return ret;
+	return __parse_numa_zonelist_order(s);
 }
 early_param("numa_zonelist_order", setup_numa_zonelist_order);
 
+char numa_zonelist_order[] = "Node";
+
 /*
  * sysctl handler for numa_zonelist_order
  */
@@ -4931,42 +4930,17 @@ int numa_zonelist_order_handler(struct ctl_table *table, int write,
 		void __user *buffer, size_t *length,
 		loff_t *ppos)
 {
-	char saved_string[NUMA_ZONELIST_ORDER_LEN];
+	char *str;
 	int ret;
-	static DEFINE_MUTEX(zl_order_mutex);
 
-	mutex_lock(&zl_order_mutex);
-	if (write) {
-		if (strlen((char *)table->data) >= NUMA_ZONELIST_ORDER_LEN) {
-			ret = -EINVAL;
-			goto out;
-		}
-		strcpy(saved_string, (char *)table->data);
-	}
-	ret = proc_dostring(table, write, buffer, length, ppos);
-	if (ret)
-		goto out;
-	if (write) {
-		int oldval = user_zonelist_order;
+	if (!write)
+		return proc_dostring(table, write, buffer, length, ppos);
+	str = memdup_user_nul(buffer, 16);
+	if (IS_ERR(str))
+		return PTR_ERR(str);
 
-		ret = __parse_numa_zonelist_order((char *)table->data);
-		if (ret) {
-			/*
-			 * bogus value.  restore saved string
-			 */
-			strncpy((char *)table->data, saved_string,
-				NUMA_ZONELIST_ORDER_LEN);
-			user_zonelist_order = oldval;
-		} else if (oldval != user_zonelist_order) {
-			mem_hotplug_begin();
-			mutex_lock(&zonelists_mutex);
-			build_all_zonelists(NULL, NULL);
-			mutex_unlock(&zonelists_mutex);
-			mem_hotplug_done();
-		}
-	}
-out:
-	mutex_unlock(&zl_order_mutex);
+	ret = __parse_numa_zonelist_order(str);
+	kfree(str);
 	return ret;
 }
 
@@ -5040,17 +5014,24 @@ static int find_next_best_node(int node, nodemask_t *used_node_mask)
  * This results in maximum locality--normal zone overflows into local
  * DMA zone, if any--but risks exhausting DMA zone.
  */
-static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
+static void build_zonelists_in_node_order(pg_data_t *pgdat, int *node_order,
+		unsigned nr_nodes)
 {
-	int j;
-	struct zonelist *zonelist;
+	struct zoneref *zonerefs;
+	int i;
+
+	zonerefs = pgdat->node_zonelists[ZONELIST_FALLBACK]._zonerefs;
+
+	for (i = 0; i < nr_nodes; i++) {
+		int nr_zones;
 
-	zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK];
-	for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
-		;
-	j = build_zonelists_node(NODE_DATA(node), zonelist, j);
-	zonelist->_zonerefs[j].zone = NULL;
-	zonelist->_zonerefs[j].zone_idx = 0;
+		pg_data_t *node = NODE_DATA(node_order[i]);
+
+		nr_zones = build_zonerefs_node(node, zonerefs);
+		zonerefs += nr_zones;
+	}
+	zonerefs->zone = NULL;
+	zonerefs->zone_idx = 0;
 }
 
 /*
@@ -5058,13 +5039,14 @@ static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
  */
 static void build_thisnode_zonelists(pg_data_t *pgdat)
 {
-	int j;
-	struct zonelist *zonelist;
+	struct zoneref *zonerefs;
+	int nr_zones;
 
-	zonelist = &pgdat->node_zonelists[ZONELIST_NOFALLBACK];
-	j = build_zonelists_node(pgdat, zonelist, 0);
-	zonelist->_zonerefs[j].zone = NULL;
-	zonelist->_zonerefs[j].zone_idx = 0;
+	zonerefs = pgdat->node_zonelists[ZONELIST_NOFALLBACK]._zonerefs;
+	nr_zones = build_zonerefs_node(pgdat, zonerefs);
+	zonerefs += nr_zones;
+	zonerefs->zone = NULL;
+	zonerefs->zone_idx = 0;
 }
 
 /*
@@ -5073,79 +5055,13 @@ static void build_thisnode_zonelists(pg_data_t *pgdat)
  * exhausted, but results in overflowing to remote node while memory
  * may still exist in local DMA zone.
  */
-static int node_order[MAX_NUMNODES];
-
-static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
-{
-	int pos, j, node;
-	int zone_type;		/* needs to be signed */
-	struct zone *z;
-	struct zonelist *zonelist;
-
-	zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK];
-	pos = 0;
-	for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
-		for (j = 0; j < nr_nodes; j++) {
-			node = node_order[j];
-			z = &NODE_DATA(node)->node_zones[zone_type];
-			if (managed_zone(z)) {
-				zoneref_set_zone(z,
-					&zonelist->_zonerefs[pos++]);
-				check_highest_zone(zone_type);
-			}
-		}
-	}
-	zonelist->_zonerefs[pos].zone = NULL;
-	zonelist->_zonerefs[pos].zone_idx = 0;
-}
-
-#if defined(CONFIG_64BIT)
-/*
- * Devices that require DMA32/DMA are relatively rare and do not justify a
- * penalty to every machine in case the specialised case applies. Default
- * to Node-ordering on 64-bit NUMA machines
- */
-static int default_zonelist_order(void)
-{
-	return ZONELIST_ORDER_NODE;
-}
-#else
-/*
- * On 32-bit, the Normal zone needs to be preserved for allocations accessible
- * by the kernel. If processes running on node 0 deplete the low memory zone
- * then reclaim will occur more frequency increasing stalls and potentially
- * be easier to OOM if a large percentage of the zone is under writeback or
- * dirty. The problem is significantly worse if CONFIG_HIGHPTE is not set.
- * Hence, default to zone ordering on 32-bit.
- */
-static int default_zonelist_order(void)
-{
-	return ZONELIST_ORDER_ZONE;
-}
-#endif /* CONFIG_64BIT */
-
-static void set_zonelist_order(void)
-{
-	if (user_zonelist_order == ZONELIST_ORDER_DEFAULT)
-		current_zonelist_order = default_zonelist_order();
-	else
-		current_zonelist_order = user_zonelist_order;
-}
 
 static void build_zonelists(pg_data_t *pgdat)
 {
-	int i, node, load;
+	static int node_order[MAX_NUMNODES];
+	int node, load, nr_nodes = 0;
 	nodemask_t used_mask;
 	int local_node, prev_node;
-	struct zonelist *zonelist;
-	unsigned int order = current_zonelist_order;
-
-	/* initialize zonelists */
-	for (i = 0; i < MAX_ZONELISTS; i++) {
-		zonelist = pgdat->node_zonelists + i;
-		zonelist->_zonerefs[0].zone = NULL;
-		zonelist->_zonerefs[0].zone_idx = 0;
-	}
 
 	/* NUMA-aware ordering of nodes */
 	local_node = pgdat->node_id;
@@ -5154,8 +5070,6 @@ static void build_zonelists(pg_data_t *pgdat)
 	nodes_clear(used_mask);
 
 	memset(node_order, 0, sizeof(node_order));
-	i = 0;
-
 	while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
 		/*
 		 * We don't want to pressure a particular node.
@@ -5166,19 +5080,12 @@ static void build_zonelists(pg_data_t *pgdat)
 		    node_distance(local_node, prev_node))
 			node_load[node] = load;
 
+		node_order[nr_nodes++] = node;
 		prev_node = node;
 		load--;
-		if (order == ZONELIST_ORDER_NODE)
-			build_zonelists_in_node_order(pgdat, node);
-		else
-			node_order[i++] = node;	/* remember order */
-	}
-
-	if (order == ZONELIST_ORDER_ZONE) {
-		/* calculate node order -- i.e., DMA last! */
-		build_zonelists_in_zone_order(pgdat, i);
 	}
 
+	build_zonelists_in_node_order(pgdat, node_order, nr_nodes);
 	build_thisnode_zonelists(pgdat);
 }
 
@@ -5204,21 +5111,17 @@ static void setup_min_unmapped_ratio(void);
 static void setup_min_slab_ratio(void);
 #else	/* CONFIG_NUMA */
 
-static void set_zonelist_order(void)
-{
-	current_zonelist_order = ZONELIST_ORDER_ZONE;
-}
-
 static void build_zonelists(pg_data_t *pgdat)
 {
 	int node, local_node;
-	enum zone_type j;
-	struct zonelist *zonelist;
+	struct zoneref *zonerefs;
+	int nr_zones;
 
 	local_node = pgdat->node_id;
 
-	zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK];
-	j = build_zonelists_node(pgdat, zonelist, 0);
+	zonerefs = pgdat->node_zonelists[ZONELIST_FALLBACK]._zonerefs;
+	nr_zones = build_zonerefs_node(pgdat, zonerefs);
+	zonerefs += nr_zones;
 
 	/*
 	 * Now we build the zonelist so that it contains the zones
@@ -5231,16 +5134,18 @@ static void build_zonelists(pg_data_t *pgdat)
 	for (node = local_node + 1; node < MAX_NUMNODES; node++) {
 		if (!node_online(node))
 			continue;
-		j = build_zonelists_node(NODE_DATA(node), zonelist, j);
+		nr_zones = build_zonerefs_node(NODE_DATA(node), zonerefs);
+		zonerefs += nr_zones;
 	}
 	for (node = 0; node < local_node; node++) {
 		if (!node_online(node))
 			continue;
-		j = build_zonelists_node(NODE_DATA(node), zonelist, j);
+		nr_zones = build_zonerefs_node(NODE_DATA(node), zonerefs);
+		zonerefs += nr_zones;
 	}
 
-	zonelist->_zonerefs[j].zone = NULL;
-	zonelist->_zonerefs[j].zone_idx = 0;
+	zonerefs->zone = NULL;
+	zonerefs->zone_idx = 0;
 }
 
 #endif	/* CONFIG_NUMA */
@@ -5263,50 +5168,32 @@ static void build_zonelists(pg_data_t *pgdat)
 static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
 static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
 static DEFINE_PER_CPU(struct per_cpu_nodestat, boot_nodestats);
-static void setup_zone_pageset(struct zone *zone);
-
-/*
- * Global mutex to protect against size modification of zonelists
- * as well as to serialize pageset setup for the new populated zone.
- */
-DEFINE_MUTEX(zonelists_mutex);
 
-/* return values int ....just for stop_machine() */
-static int __build_all_zonelists(void *data)
+static void __build_all_zonelists(void *data)
 {
 	int nid;
-	int cpu;
+	int __maybe_unused cpu;
 	pg_data_t *self = data;
+	static DEFINE_SPINLOCK(lock);
+
+	spin_lock(&lock);
 
 #ifdef CONFIG_NUMA
 	memset(node_load, 0, sizeof(node_load));
 #endif
 
+	/*
+	 * This node is hotadded and no memory is yet present.   So just
+	 * building zonelists is fine - no need to touch other nodes.
+	 */
 	if (self && !node_online(self->node_id)) {
 		build_zonelists(self);
-	}
-
-	for_each_online_node(nid) {
-		pg_data_t *pgdat = NODE_DATA(nid);
-
-		build_zonelists(pgdat);
-	}
+	} else {
+		for_each_online_node(nid) {
+			pg_data_t *pgdat = NODE_DATA(nid);
 
-	/*
-	 * Initialize the boot_pagesets that are going to be used
-	 * for bootstrapping processors. The real pagesets for
-	 * each zone will be allocated later when the per cpu
-	 * allocator is available.
-	 *
-	 * boot_pagesets are used also for bootstrapping offline
-	 * cpus if the system is already booted because the pagesets
-	 * are needed to initialize allocators on a specific cpu too.
-	 * F.e. the percpu allocator needs the page allocator which
-	 * needs the percpu allocator in order to allocate its pagesets
-	 * (a chicken-egg dilemma).
-	 */
-	for_each_possible_cpu(cpu) {
-		setup_pageset(&per_cpu(boot_pageset, cpu), 0);
+			build_zonelists(pgdat);
+		}
 
 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
 		/*
@@ -5317,45 +5204,53 @@ static int __build_all_zonelists(void *data)
 		 * secondary cpus' numa_mem as they come on-line.  During
 		 * node/memory hotplug, we'll fixup all on-line cpus.
 		 */
-		if (cpu_online(cpu))
+		for_each_online_cpu(cpu)
 			set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
 #endif
 	}
 
-	return 0;
+	spin_unlock(&lock);
 }
 
 static noinline void __init
 build_all_zonelists_init(void)
 {
+	int cpu;
+
 	__build_all_zonelists(NULL);
+
+	/*
+	 * Initialize the boot_pagesets that are going to be used
+	 * for bootstrapping processors. The real pagesets for
+	 * each zone will be allocated later when the per cpu
+	 * allocator is available.
+	 *
+	 * boot_pagesets are used also for bootstrapping offline
+	 * cpus if the system is already booted because the pagesets
+	 * are needed to initialize allocators on a specific cpu too.
+	 * F.e. the percpu allocator needs the page allocator which
+	 * needs the percpu allocator in order to allocate its pagesets
+	 * (a chicken-egg dilemma).
+	 */
+	for_each_possible_cpu(cpu)
+		setup_pageset(&per_cpu(boot_pageset, cpu), 0);
+
 	mminit_verify_zonelist();
 	cpuset_init_current_mems_allowed();
 }
 
 /*
- * Called with zonelists_mutex held always
  * unless system_state == SYSTEM_BOOTING.
  *
- * __ref due to (1) call of __meminit annotated setup_zone_pageset
- * [we're only called with non-NULL zone through __meminit paths] and
- * (2) call of __init annotated helper build_all_zonelists_init
+ * __ref due to call of __init annotated helper build_all_zonelists_init
  * [protected by SYSTEM_BOOTING].
  */
-void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone)
+void __ref build_all_zonelists(pg_data_t *pgdat)
 {
-	set_zonelist_order();
-
 	if (system_state == SYSTEM_BOOTING) {
 		build_all_zonelists_init();
 	} else {
-#ifdef CONFIG_MEMORY_HOTPLUG
-		if (zone)
-			setup_zone_pageset(zone);
-#endif
-		/* we have to stop all cpus to guarantee there is no user
-		   of zonelist */
-		stop_machine_cpuslocked(__build_all_zonelists, pgdat, NULL);
+		__build_all_zonelists(pgdat);
 		/* cpuset refresh routine should be here */
 	}
 	vm_total_pages = nr_free_pagecache_pages();
@@ -5371,9 +5266,8 @@ void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone)
 	else
 		page_group_by_mobility_disabled = 0;
 
-	pr_info("Built %i zonelists in %s order, mobility grouping %s.  Total pages: %ld\n",
+	pr_info("Built %i zonelists, mobility grouping %s.  Total pages: %ld\n",
 		nr_online_nodes,
-		zonelist_order_name[current_zonelist_order],
 		page_group_by_mobility_disabled ? "off" : "on",
 		vm_total_pages);
 #ifdef CONFIG_NUMA
@@ -5627,7 +5521,7 @@ static void __meminit zone_pageset_init(struct zone *zone, int cpu)
 	pageset_set_high_and_batch(zone, pcp);
 }
 
-static void __meminit setup_zone_pageset(struct zone *zone)
+void __meminit setup_zone_pageset(struct zone *zone)
 {
 	int cpu;
 	zone->pageset = alloc_percpu(struct per_cpu_pageset);
@@ -7081,9 +6975,11 @@ static void __setup_per_zone_wmarks(void)
  */
 void setup_per_zone_wmarks(void)
 {
-	mutex_lock(&zonelists_mutex);
+	static DEFINE_SPINLOCK(lock);
+
+	spin_lock(&lock);
 	__setup_per_zone_wmarks();
-	mutex_unlock(&zonelists_mutex);
+	spin_unlock(&lock);
 }
 
 /*
diff --git a/mm/page_ext.c b/mm/page_ext.c
index 88ccc044b09a..32f18911deda 100644
--- a/mm/page_ext.c
+++ b/mm/page_ext.c
@@ -222,10 +222,7 @@ static void *__meminit alloc_page_ext(size_t size, int nid)
 		return addr;
 	}
 
-	if (node_state(nid, N_HIGH_MEMORY))
-		addr = vzalloc_node(size, nid);
-	else
-		addr = vzalloc(size);
+	addr = vzalloc_node(size, nid);
 
 	return addr;
 }
@@ -409,6 +406,7 @@ void __init page_ext_init(void)
 				continue;
 			if (init_section_page_ext(pfn, nid))
 				goto oom;
+			cond_resched();
 		}
 	}
 	hotplug_memory_notifier(page_ext_callback, 0);
diff --git a/mm/page_idle.c b/mm/page_idle.c
index 1b0f48c62316..4bd03a8d809e 100644
--- a/mm/page_idle.c
+++ b/mm/page_idle.c
@@ -204,7 +204,7 @@ static struct bin_attribute *page_idle_bin_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group page_idle_attr_group = {
+static const struct attribute_group page_idle_attr_group = {
 	.bin_attrs = page_idle_bin_attrs,
 	.name = "page_idle",
 };
diff --git a/mm/page_io.c b/mm/page_io.c
index 5f61b54ee1f3..20139b90125a 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -28,16 +28,18 @@
 static struct bio *get_swap_bio(gfp_t gfp_flags,
 				struct page *page, bio_end_io_t end_io)
 {
+	int i, nr = hpage_nr_pages(page);
 	struct bio *bio;
 
-	bio = bio_alloc(gfp_flags, 1);
+	bio = bio_alloc(gfp_flags, nr);
 	if (bio) {
 		bio->bi_iter.bi_sector = map_swap_page(page, &bio->bi_bdev);
 		bio->bi_iter.bi_sector <<= PAGE_SHIFT - 9;
 		bio->bi_end_io = end_io;
 
-		bio_add_page(bio, page, PAGE_SIZE, 0);
-		BUG_ON(bio->bi_iter.bi_size != PAGE_SIZE);
+		for (i = 0; i < nr; i++)
+			bio_add_page(bio, page + i, PAGE_SIZE, 0);
+		VM_BUG_ON(bio->bi_iter.bi_size != PAGE_SIZE * nr);
 	}
 	return bio;
 }
@@ -262,6 +264,15 @@ static sector_t swap_page_sector(struct page *page)
 	return (sector_t)__page_file_index(page) << (PAGE_SHIFT - 9);
 }
 
+static inline void count_swpout_vm_event(struct page *page)
+{
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+	if (unlikely(PageTransHuge(page)))
+		count_vm_event(THP_SWPOUT);
+#endif
+	count_vm_events(PSWPOUT, hpage_nr_pages(page));
+}
+
 int __swap_writepage(struct page *page, struct writeback_control *wbc,
 		bio_end_io_t end_write_func)
 {
@@ -313,7 +324,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 
 	ret = bdev_write_page(sis->bdev, swap_page_sector(page), page, wbc);
 	if (!ret) {
-		count_vm_event(PSWPOUT);
+		count_swpout_vm_event(page);
 		return 0;
 	}
 
@@ -326,7 +337,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc,
 		goto out;
 	}
 	bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc);
-	count_vm_event(PSWPOUT);
+	count_swpout_vm_event(page);
 	set_page_writeback(page);
 	unlock_page(page);
 	submit_bio(bio);
diff --git a/mm/page_owner.c b/mm/page_owner.c
index 0fd9dcf2c5dc..8e2d7137510c 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -30,6 +30,7 @@ DEFINE_STATIC_KEY_FALSE(page_owner_inited);
 
 static depot_stack_handle_t dummy_handle;
 static depot_stack_handle_t failure_handle;
+static depot_stack_handle_t early_handle;
 
 static void init_early_allocated_pages(void);
 
@@ -53,7 +54,7 @@ static bool need_page_owner(void)
 	return true;
 }
 
-static noinline void register_dummy_stack(void)
+static __always_inline depot_stack_handle_t create_dummy_stack(void)
 {
 	unsigned long entries[4];
 	struct stack_trace dummy;
@@ -64,21 +65,22 @@ static noinline void register_dummy_stack(void)
 	dummy.skip = 0;
 
 	save_stack_trace(&dummy);
-	dummy_handle = depot_save_stack(&dummy, GFP_KERNEL);
+	return depot_save_stack(&dummy, GFP_KERNEL);
 }
 
-static noinline void register_failure_stack(void)
+static noinline void register_dummy_stack(void)
 {
-	unsigned long entries[4];
-	struct stack_trace failure;
+	dummy_handle = create_dummy_stack();
+}
 
-	failure.nr_entries = 0;
-	failure.max_entries = ARRAY_SIZE(entries);
-	failure.entries = &entries[0];
-	failure.skip = 0;
+static noinline void register_failure_stack(void)
+{
+	failure_handle = create_dummy_stack();
+}
 
-	save_stack_trace(&failure);
-	failure_handle = depot_save_stack(&failure, GFP_KERNEL);
+static noinline void register_early_stack(void)
+{
+	early_handle = create_dummy_stack();
 }
 
 static void init_page_owner(void)
@@ -88,6 +90,7 @@ static void init_page_owner(void)
 
 	register_dummy_stack();
 	register_failure_stack();
+	register_early_stack();
 	static_branch_enable(&page_owner_inited);
 	init_early_allocated_pages();
 }
@@ -165,17 +168,13 @@ static noinline depot_stack_handle_t save_stack(gfp_t flags)
 	return handle;
 }
 
-noinline void __set_page_owner(struct page *page, unsigned int order,
-					gfp_t gfp_mask)
+static inline void __set_page_owner_handle(struct page_ext *page_ext,
+	depot_stack_handle_t handle, unsigned int order, gfp_t gfp_mask)
 {
-	struct page_ext *page_ext = lookup_page_ext(page);
 	struct page_owner *page_owner;
 
-	if (unlikely(!page_ext))
-		return;
-
 	page_owner = get_page_owner(page_ext);
-	page_owner->handle = save_stack(gfp_mask);
+	page_owner->handle = handle;
 	page_owner->order = order;
 	page_owner->gfp_mask = gfp_mask;
 	page_owner->last_migrate_reason = -1;
@@ -183,6 +182,19 @@ noinline void __set_page_owner(struct page *page, unsigned int order,
 	__set_bit(PAGE_EXT_OWNER, &page_ext->flags);
 }
 
+noinline void __set_page_owner(struct page *page, unsigned int order,
+					gfp_t gfp_mask)
+{
+	struct page_ext *page_ext = lookup_page_ext(page);
+	depot_stack_handle_t handle;
+
+	if (unlikely(!page_ext))
+		return;
+
+	handle = save_stack(gfp_mask);
+	__set_page_owner_handle(page_ext, handle, order, gfp_mask);
+}
+
 void __set_page_owner_migrate_reason(struct page *page, int reason)
 {
 	struct page_ext *page_ext = lookup_page_ext(page);
@@ -550,11 +562,17 @@ static void init_pages_in_zone(pg_data_t *pgdat, struct zone *zone)
 				continue;
 
 			/*
-			 * We are safe to check buddy flag and order, because
-			 * this is init stage and only single thread runs.
+			 * To avoid having to grab zone->lock, be a little
+			 * careful when reading buddy page order. The only
+			 * danger is that we skip too much and potentially miss
+			 * some early allocated pages, which is better than
+			 * heavy lock contention.
 			 */
 			if (PageBuddy(page)) {
-				pfn += (1UL << page_order(page)) - 1;
+				unsigned long order = page_order_unsafe(page);
+
+				if (order > 0 && order < MAX_ORDER)
+					pfn += (1UL << order) - 1;
 				continue;
 			}
 
@@ -565,14 +583,15 @@ static void init_pages_in_zone(pg_data_t *pgdat, struct zone *zone)
 			if (unlikely(!page_ext))
 				continue;
 
-			/* Maybe overraping zone */
+			/* Maybe overlapping zone */
 			if (test_bit(PAGE_EXT_OWNER, &page_ext->flags))
 				continue;
 
 			/* Found early allocated page */
-			set_page_owner(page, 0, 0);
+			__set_page_owner_handle(page_ext, early_handle, 0, 0);
 			count++;
 		}
+		cond_resched();
 	}
 
 	pr_info("Node %d, zone %8s: page owner found early allocated %lu pages\n",
@@ -583,15 +602,12 @@ static void init_zones_in_node(pg_data_t *pgdat)
 {
 	struct zone *zone;
 	struct zone *node_zones = pgdat->node_zones;
-	unsigned long flags;
 
 	for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
 		if (!populated_zone(zone))
 			continue;
 
-		spin_lock_irqsave(&zone->lock, flags);
 		init_pages_in_zone(pgdat, zone);
-		spin_unlock_irqrestore(&zone->lock, flags);
 	}
 }
 
diff --git a/mm/shmem.c b/mm/shmem.c
index fbcb3c96a186..ace53a582be5 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -34,6 +34,7 @@
 #include <linux/swap.h>
 #include <linux/uio.h>
 #include <linux/khugepaged.h>
+#include <linux/hugetlb.h>
 
 #include <asm/tlbflush.h> /* for arch/microblaze update_mmu_cache() */
 
@@ -188,6 +189,38 @@ static inline void shmem_unacct_blocks(unsigned long flags, long pages)
 		vm_unacct_memory(pages * VM_ACCT(PAGE_SIZE));
 }
 
+static inline bool shmem_inode_acct_block(struct inode *inode, long pages)
+{
+	struct shmem_inode_info *info = SHMEM_I(inode);
+	struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
+
+	if (shmem_acct_block(info->flags, pages))
+		return false;
+
+	if (sbinfo->max_blocks) {
+		if (percpu_counter_compare(&sbinfo->used_blocks,
+					   sbinfo->max_blocks - pages) > 0)
+			goto unacct;
+		percpu_counter_add(&sbinfo->used_blocks, pages);
+	}
+
+	return true;
+
+unacct:
+	shmem_unacct_blocks(info->flags, pages);
+	return false;
+}
+
+static inline void shmem_inode_unacct_blocks(struct inode *inode, long pages)
+{
+	struct shmem_inode_info *info = SHMEM_I(inode);
+	struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
+
+	if (sbinfo->max_blocks)
+		percpu_counter_sub(&sbinfo->used_blocks, pages);
+	shmem_unacct_blocks(info->flags, pages);
+}
+
 static const struct super_operations shmem_ops;
 static const struct address_space_operations shmem_aops;
 static const struct file_operations shmem_file_operations;
@@ -249,23 +282,20 @@ static void shmem_recalc_inode(struct inode *inode)
 
 	freed = info->alloced - info->swapped - inode->i_mapping->nrpages;
 	if (freed > 0) {
-		struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
-		if (sbinfo->max_blocks)
-			percpu_counter_add(&sbinfo->used_blocks, -freed);
 		info->alloced -= freed;
 		inode->i_blocks -= freed * BLOCKS_PER_PAGE;
-		shmem_unacct_blocks(info->flags, freed);
+		shmem_inode_unacct_blocks(inode, freed);
 	}
 }
 
 bool shmem_charge(struct inode *inode, long pages)
 {
 	struct shmem_inode_info *info = SHMEM_I(inode);
-	struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
 	unsigned long flags;
 
-	if (shmem_acct_block(info->flags, pages))
+	if (!shmem_inode_acct_block(inode, pages))
 		return false;
+
 	spin_lock_irqsave(&info->lock, flags);
 	info->alloced += pages;
 	inode->i_blocks += pages * BLOCKS_PER_PAGE;
@@ -273,26 +303,12 @@ bool shmem_charge(struct inode *inode, long pages)
 	spin_unlock_irqrestore(&info->lock, flags);
 	inode->i_mapping->nrpages += pages;
 
-	if (!sbinfo->max_blocks)
-		return true;
-	if (percpu_counter_compare(&sbinfo->used_blocks,
-				sbinfo->max_blocks - pages) > 0) {
-		inode->i_mapping->nrpages -= pages;
-		spin_lock_irqsave(&info->lock, flags);
-		info->alloced -= pages;
-		shmem_recalc_inode(inode);
-		spin_unlock_irqrestore(&info->lock, flags);
-		shmem_unacct_blocks(info->flags, pages);
-		return false;
-	}
-	percpu_counter_add(&sbinfo->used_blocks, pages);
 	return true;
 }
 
 void shmem_uncharge(struct inode *inode, long pages)
 {
 	struct shmem_inode_info *info = SHMEM_I(inode);
-	struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
 	unsigned long flags;
 
 	spin_lock_irqsave(&info->lock, flags);
@@ -301,9 +317,7 @@ void shmem_uncharge(struct inode *inode, long pages)
 	shmem_recalc_inode(inode);
 	spin_unlock_irqrestore(&info->lock, flags);
 
-	if (sbinfo->max_blocks)
-		percpu_counter_sub(&sbinfo->used_blocks, pages);
-	shmem_unacct_blocks(info->flags, pages);
+	shmem_inode_unacct_blocks(inode, pages);
 }
 
 /*
@@ -1452,9 +1466,10 @@ static struct page *shmem_alloc_page(gfp_t gfp,
 }
 
 static struct page *shmem_alloc_and_acct_page(gfp_t gfp,
-		struct shmem_inode_info *info, struct shmem_sb_info *sbinfo,
+		struct inode *inode,
 		pgoff_t index, bool huge)
 {
+	struct shmem_inode_info *info = SHMEM_I(inode);
 	struct page *page;
 	int nr;
 	int err = -ENOSPC;
@@ -1463,14 +1478,8 @@ static struct page *shmem_alloc_and_acct_page(gfp_t gfp,
 		huge = false;
 	nr = huge ? HPAGE_PMD_NR : 1;
 
-	if (shmem_acct_block(info->flags, nr))
+	if (!shmem_inode_acct_block(inode, nr))
 		goto failed;
-	if (sbinfo->max_blocks) {
-		if (percpu_counter_compare(&sbinfo->used_blocks,
-					sbinfo->max_blocks - nr) > 0)
-			goto unacct;
-		percpu_counter_add(&sbinfo->used_blocks, nr);
-	}
 
 	if (huge)
 		page = shmem_alloc_hugepage(gfp, info, index);
@@ -1483,10 +1492,7 @@ static struct page *shmem_alloc_and_acct_page(gfp_t gfp,
 	}
 
 	err = -ENOMEM;
-	if (sbinfo->max_blocks)
-		percpu_counter_add(&sbinfo->used_blocks, -nr);
-unacct:
-	shmem_unacct_blocks(info->flags, nr);
+	shmem_inode_unacct_blocks(inode, nr);
 failed:
 	return ERR_PTR(err);
 }
@@ -1644,7 +1650,7 @@ repeat:
 
 	if (swap.val) {
 		/* Look it up and read it in.. */
-		page = lookup_swap_cache(swap);
+		page = lookup_swap_cache(swap, NULL, 0);
 		if (!page) {
 			/* Or update major stats only when swapin succeeds?? */
 			if (fault_type) {
@@ -1751,10 +1757,9 @@ repeat:
 		}
 
 alloc_huge:
-		page = shmem_alloc_and_acct_page(gfp, info, sbinfo,
-				index, true);
+		page = shmem_alloc_and_acct_page(gfp, inode, index, true);
 		if (IS_ERR(page)) {
-alloc_nohuge:		page = shmem_alloc_and_acct_page(gfp, info, sbinfo,
+alloc_nohuge:		page = shmem_alloc_and_acct_page(gfp, inode,
 					index, false);
 		}
 		if (IS_ERR(page)) {
@@ -1876,10 +1881,7 @@ clear:
 	 * Error recovery.
 	 */
 unacct:
-	if (sbinfo->max_blocks)
-		percpu_counter_sub(&sbinfo->used_blocks,
-				1 << compound_order(page));
-	shmem_unacct_blocks(info->flags, 1 << compound_order(page));
+	shmem_inode_unacct_blocks(inode, 1 << compound_order(page));
 
 	if (PageTransHuge(page)) {
 		unlock_page(page);
@@ -2206,16 +2208,16 @@ bool shmem_mapping(struct address_space *mapping)
 	return mapping->a_ops == &shmem_aops;
 }
 
-int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm,
-			   pmd_t *dst_pmd,
-			   struct vm_area_struct *dst_vma,
-			   unsigned long dst_addr,
-			   unsigned long src_addr,
-			   struct page **pagep)
+static int shmem_mfill_atomic_pte(struct mm_struct *dst_mm,
+				  pmd_t *dst_pmd,
+				  struct vm_area_struct *dst_vma,
+				  unsigned long dst_addr,
+				  unsigned long src_addr,
+				  bool zeropage,
+				  struct page **pagep)
 {
 	struct inode *inode = file_inode(dst_vma->vm_file);
 	struct shmem_inode_info *info = SHMEM_I(inode);
-	struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
 	struct address_space *mapping = inode->i_mapping;
 	gfp_t gfp = mapping_gfp_mask(mapping);
 	pgoff_t pgoff = linear_page_index(dst_vma, dst_addr);
@@ -2227,33 +2229,30 @@ int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm,
 	int ret;
 
 	ret = -ENOMEM;
-	if (shmem_acct_block(info->flags, 1))
+	if (!shmem_inode_acct_block(inode, 1))
 		goto out;
-	if (sbinfo->max_blocks) {
-		if (percpu_counter_compare(&sbinfo->used_blocks,
-					   sbinfo->max_blocks) >= 0)
-			goto out_unacct_blocks;
-		percpu_counter_inc(&sbinfo->used_blocks);
-	}
 
 	if (!*pagep) {
 		page = shmem_alloc_page(gfp, info, pgoff);
 		if (!page)
-			goto out_dec_used_blocks;
-
-		page_kaddr = kmap_atomic(page);
-		ret = copy_from_user(page_kaddr, (const void __user *)src_addr,
-				     PAGE_SIZE);
-		kunmap_atomic(page_kaddr);
-
-		/* fallback to copy_from_user outside mmap_sem */
-		if (unlikely(ret)) {
-			*pagep = page;
-			if (sbinfo->max_blocks)
-				percpu_counter_add(&sbinfo->used_blocks, -1);
-			shmem_unacct_blocks(info->flags, 1);
-			/* don't free the page */
-			return -EFAULT;
+			goto out_unacct_blocks;
+
+		if (!zeropage) {	/* mcopy_atomic */
+			page_kaddr = kmap_atomic(page);
+			ret = copy_from_user(page_kaddr,
+					     (const void __user *)src_addr,
+					     PAGE_SIZE);
+			kunmap_atomic(page_kaddr);
+
+			/* fallback to copy_from_user outside mmap_sem */
+			if (unlikely(ret)) {
+				*pagep = page;
+				shmem_inode_unacct_blocks(inode, 1);
+				/* don't free the page */
+				return -EFAULT;
+			}
+		} else {		/* mfill_zeropage_atomic */
+			clear_highpage(page);
 		}
 	} else {
 		page = *pagep;
@@ -2314,14 +2313,33 @@ out_release_uncharge:
 out_release:
 	unlock_page(page);
 	put_page(page);
-out_dec_used_blocks:
-	if (sbinfo->max_blocks)
-		percpu_counter_add(&sbinfo->used_blocks, -1);
 out_unacct_blocks:
-	shmem_unacct_blocks(info->flags, 1);
+	shmem_inode_unacct_blocks(inode, 1);
 	goto out;
 }
 
+int shmem_mcopy_atomic_pte(struct mm_struct *dst_mm,
+			   pmd_t *dst_pmd,
+			   struct vm_area_struct *dst_vma,
+			   unsigned long dst_addr,
+			   unsigned long src_addr,
+			   struct page **pagep)
+{
+	return shmem_mfill_atomic_pte(dst_mm, dst_pmd, dst_vma,
+				      dst_addr, src_addr, false, pagep);
+}
+
+int shmem_mfill_zeropage_pte(struct mm_struct *dst_mm,
+			     pmd_t *dst_pmd,
+			     struct vm_area_struct *dst_vma,
+			     unsigned long dst_addr)
+{
+	struct page *page = NULL;
+
+	return shmem_mfill_atomic_pte(dst_mm, dst_pmd, dst_vma,
+				      dst_addr, 0, true, &page);
+}
+
 #ifdef CONFIG_TMPFS
 static const struct inode_operations shmem_symlink_inode_operations;
 static const struct inode_operations shmem_short_symlink_operations;
@@ -3635,7 +3653,7 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root)
 #define MFD_NAME_PREFIX_LEN (sizeof(MFD_NAME_PREFIX) - 1)
 #define MFD_NAME_MAX_LEN (NAME_MAX - MFD_NAME_PREFIX_LEN)
 
-#define MFD_ALL_FLAGS (MFD_CLOEXEC | MFD_ALLOW_SEALING)
+#define MFD_ALL_FLAGS (MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_HUGETLB)
 
 SYSCALL_DEFINE2(memfd_create,
 		const char __user *, uname,
@@ -3647,8 +3665,18 @@ SYSCALL_DEFINE2(memfd_create,
 	char *name;
 	long len;
 
-	if (flags & ~(unsigned int)MFD_ALL_FLAGS)
-		return -EINVAL;
+	if (!(flags & MFD_HUGETLB)) {
+		if (flags & ~(unsigned int)MFD_ALL_FLAGS)
+			return -EINVAL;
+	} else {
+		/* Sealing not supported in hugetlbfs (MFD_HUGETLB) */
+		if (flags & MFD_ALLOW_SEALING)
+			return -EINVAL;
+		/* Allow huge page size encoding in flags. */
+		if (flags & ~(unsigned int)(MFD_ALL_FLAGS |
+				(MFD_HUGE_MASK << MFD_HUGE_SHIFT)))
+			return -EINVAL;
+	}
 
 	/* length includes terminating zero */
 	len = strnlen_user(uname, MFD_NAME_MAX_LEN + 1);
@@ -3679,16 +3707,30 @@ SYSCALL_DEFINE2(memfd_create,
 		goto err_name;
 	}
 
-	file = shmem_file_setup(name, 0, VM_NORESERVE);
+	if (flags & MFD_HUGETLB) {
+		struct user_struct *user = NULL;
+
+		file = hugetlb_file_setup(name, 0, VM_NORESERVE, &user,
+					HUGETLB_ANONHUGE_INODE,
+					(flags >> MFD_HUGE_SHIFT) &
+					MFD_HUGE_MASK);
+	} else
+		file = shmem_file_setup(name, 0, VM_NORESERVE);
 	if (IS_ERR(file)) {
 		error = PTR_ERR(file);
 		goto err_fd;
 	}
-	info = SHMEM_I(file_inode(file));
 	file->f_mode |= FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE;
 	file->f_flags |= O_RDWR | O_LARGEFILE;
-	if (flags & MFD_ALLOW_SEALING)
+
+	if (flags & MFD_ALLOW_SEALING) {
+		/*
+		 * flags check at beginning of function ensures
+		 * this is not a hugetlbfs (MFD_HUGETLB) file.
+		 */
+		info = SHMEM_I(file_inode(file));
 		info->seals &= ~F_SEAL_SEAL;
+	}
 
 	fd_install(fd, file);
 	kfree(name);
diff --git a/mm/slub.c b/mm/slub.c
index e8b4e31162ca..ddb04576b342 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -34,6 +34,7 @@
 #include <linux/stacktrace.h>
 #include <linux/prefetch.h>
 #include <linux/memcontrol.h>
+#include <linux/random.h>
 
 #include <trace/events/kmem.h>
 
@@ -238,30 +239,62 @@ static inline void stat(const struct kmem_cache *s, enum stat_item si)
  * 			Core slab cache functions
  *******************************************************************/
 
+/*
+ * Returns freelist pointer (ptr). With hardening, this is obfuscated
+ * with an XOR of the address where the pointer is held and a per-cache
+ * random number.
+ */
+static inline void *freelist_ptr(const struct kmem_cache *s, void *ptr,
+				 unsigned long ptr_addr)
+{
+#ifdef CONFIG_SLAB_FREELIST_HARDENED
+	return (void *)((unsigned long)ptr ^ s->random ^ ptr_addr);
+#else
+	return ptr;
+#endif
+}
+
+/* Returns the freelist pointer recorded at location ptr_addr. */
+static inline void *freelist_dereference(const struct kmem_cache *s,
+					 void *ptr_addr)
+{
+	return freelist_ptr(s, (void *)*(unsigned long *)(ptr_addr),
+			    (unsigned long)ptr_addr);
+}
+
 static inline void *get_freepointer(struct kmem_cache *s, void *object)
 {
-	return *(void **)(object + s->offset);
+	return freelist_dereference(s, object + s->offset);
 }
 
 static void prefetch_freepointer(const struct kmem_cache *s, void *object)
 {
-	prefetch(object + s->offset);
+	if (object)
+		prefetch(freelist_dereference(s, object + s->offset));
 }
 
 static inline void *get_freepointer_safe(struct kmem_cache *s, void *object)
 {
+	unsigned long freepointer_addr;
 	void *p;
 
 	if (!debug_pagealloc_enabled())
 		return get_freepointer(s, object);
 
-	probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p));
-	return p;
+	freepointer_addr = (unsigned long)object + s->offset;
+	probe_kernel_read(&p, (void **)freepointer_addr, sizeof(p));
+	return freelist_ptr(s, p, freepointer_addr);
 }
 
 static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
 {
-	*(void **)(object + s->offset) = fp;
+	unsigned long freeptr_addr = (unsigned long)object + s->offset;
+
+#ifdef CONFIG_SLAB_FREELIST_HARDENED
+	BUG_ON(object == fp); /* naive detection of double free or corruption */
+#endif
+
+	*(void **)freeptr_addr = freelist_ptr(s, fp, freeptr_addr);
 }
 
 /* Loop over all objects in a slab */
@@ -3358,8 +3391,8 @@ static void free_kmem_cache_nodes(struct kmem_cache *s)
 	struct kmem_cache_node *n;
 
 	for_each_kmem_cache_node(s, node, n) {
-		kmem_cache_free(kmem_cache_node, n);
 		s->node[node] = NULL;
+		kmem_cache_free(kmem_cache_node, n);
 	}
 }
 
@@ -3389,8 +3422,8 @@ static int init_kmem_cache_nodes(struct kmem_cache *s)
 			return 0;
 		}
 
-		s->node[node] = n;
 		init_kmem_cache_node(n);
+		s->node[node] = n;
 	}
 	return 1;
 }
@@ -3563,6 +3596,9 @@ static int kmem_cache_open(struct kmem_cache *s, unsigned long flags)
 {
 	s->flags = kmem_cache_flags(s->size, flags, s->name, s->ctor);
 	s->reserved = 0;
+#ifdef CONFIG_SLAB_FREELIST_HARDENED
+	s->random = get_random_long();
+#endif
 
 	if (need_reserve_slab_rcu && (s->flags & SLAB_TYPESAFE_BY_RCU))
 		s->reserved = sizeof(struct rcu_head);
@@ -5423,7 +5459,7 @@ static struct attribute *slab_attrs[] = {
 	NULL
 };
 
-static struct attribute_group slab_attr_group = {
+static const struct attribute_group slab_attr_group = {
 	.attrs = slab_attrs,
 };
 
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index c50b1a14d55e..d1a39b8051e0 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -54,14 +54,9 @@ void * __meminit vmemmap_alloc_block(unsigned long size, int node)
 	if (slab_is_available()) {
 		struct page *page;
 
-		if (node_state(node, N_HIGH_MEMORY))
-			page = alloc_pages_node(
-				node, GFP_KERNEL | __GFP_ZERO | __GFP_RETRY_MAYFAIL,
-				get_order(size));
-		else
-			page = alloc_pages(
-				GFP_KERNEL | __GFP_ZERO | __GFP_RETRY_MAYFAIL,
-				get_order(size));
+		page = alloc_pages_node(node,
+			GFP_KERNEL | __GFP_ZERO | __GFP_RETRY_MAYFAIL,
+			get_order(size));
 		if (page)
 			return page_address(page);
 		return NULL;
diff --git a/mm/sparse.c b/mm/sparse.c
index 7b4be3fd5cac..a9783acf2bb9 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -65,14 +65,10 @@ static noinline struct mem_section __ref *sparse_index_alloc(int nid)
 	unsigned long array_size = SECTIONS_PER_ROOT *
 				   sizeof(struct mem_section);
 
-	if (slab_is_available()) {
-		if (node_state(nid, N_HIGH_MEMORY))
-			section = kzalloc_node(array_size, GFP_KERNEL, nid);
-		else
-			section = kzalloc(array_size, GFP_KERNEL);
-	} else {
+	if (slab_is_available())
+		section = kzalloc_node(array_size, GFP_KERNEL, nid);
+	else
 		section = memblock_virt_alloc_node(array_size, nid);
-	}
 
 	return section;
 }
diff --git a/mm/swap.c b/mm/swap.c
index 60b1d2a75852..62d96b8e5eb3 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -946,28 +946,34 @@ void pagevec_remove_exceptionals(struct pagevec *pvec)
 }
 
 /**
- * pagevec_lookup - gang pagecache lookup
+ * pagevec_lookup_range - gang pagecache lookup
  * @pvec:	Where the resulting pages are placed
  * @mapping:	The address_space to search
  * @start:	The starting page index
+ * @end:	The final page index
  * @nr_pages:	The maximum number of pages
  *
- * pagevec_lookup() will search for and return a group of up to @nr_pages pages
- * in the mapping.  The pages are placed in @pvec.  pagevec_lookup() takes a
+ * pagevec_lookup_range() will search for and return a group of up to @nr_pages
+ * pages in the mapping starting from index @start and upto index @end
+ * (inclusive).  The pages are placed in @pvec.  pagevec_lookup() takes a
  * reference against the pages in @pvec.
  *
  * The search returns a group of mapping-contiguous pages with ascending
- * indexes.  There may be holes in the indices due to not-present pages.
+ * indexes.  There may be holes in the indices due to not-present pages. We
+ * also update @start to index the next page for the traversal.
  *
- * pagevec_lookup() returns the number of pages which were found.
+ * pagevec_lookup_range() returns the number of pages which were found. If this
+ * number is smaller than @nr_pages, the end of specified range has been
+ * reached.
  */
-unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
-		pgoff_t start, unsigned nr_pages)
+unsigned pagevec_lookup_range(struct pagevec *pvec,
+		struct address_space *mapping, pgoff_t *start, pgoff_t end)
 {
-	pvec->nr = find_get_pages(mapping, start, nr_pages, pvec->pages);
+	pvec->nr = find_get_pages_range(mapping, start, end, PAGEVEC_SIZE,
+					pvec->pages);
 	return pagevec_count(pvec);
 }
-EXPORT_SYMBOL(pagevec_lookup);
+EXPORT_SYMBOL(pagevec_lookup_range);
 
 unsigned pagevec_lookup_tag(struct pagevec *pvec, struct address_space *mapping,
 		pgoff_t *index, int tag, unsigned nr_pages)
diff --git a/mm/swap_state.c b/mm/swap_state.c
index b68c93014f50..71ce2d1ccbf7 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -37,6 +37,29 @@ static const struct address_space_operations swap_aops = {
 
 struct address_space *swapper_spaces[MAX_SWAPFILES];
 static unsigned int nr_swapper_spaces[MAX_SWAPFILES];
+bool swap_vma_readahead = true;
+
+#define SWAP_RA_MAX_ORDER_DEFAULT	3
+
+static int swap_ra_max_order = SWAP_RA_MAX_ORDER_DEFAULT;
+
+#define SWAP_RA_WIN_SHIFT	(PAGE_SHIFT / 2)
+#define SWAP_RA_HITS_MASK	((1UL << SWAP_RA_WIN_SHIFT) - 1)
+#define SWAP_RA_HITS_MAX	SWAP_RA_HITS_MASK
+#define SWAP_RA_WIN_MASK	(~PAGE_MASK & ~SWAP_RA_HITS_MASK)
+
+#define SWAP_RA_HITS(v)		((v) & SWAP_RA_HITS_MASK)
+#define SWAP_RA_WIN(v)		(((v) & SWAP_RA_WIN_MASK) >> SWAP_RA_WIN_SHIFT)
+#define SWAP_RA_ADDR(v)		((v) & PAGE_MASK)
+
+#define SWAP_RA_VAL(addr, win, hits)				\
+	(((addr) & PAGE_MASK) |					\
+	 (((win) << SWAP_RA_WIN_SHIFT) & SWAP_RA_WIN_MASK) |	\
+	 ((hits) & SWAP_RA_HITS_MASK))
+
+/* Initial readahead hits is 4 to start up with a small window */
+#define GET_SWAP_RA_VAL(vma)					\
+	(atomic_long_read(&(vma)->swap_readahead_info) ? : 4)
 
 #define INC_CACHE_INFO(x)	do { swap_cache_info.x++; } while (0)
 #define ADD_CACHE_INFO(x, nr)	do { swap_cache_info.x += (nr); } while (0)
@@ -297,19 +320,36 @@ void free_pages_and_swap_cache(struct page **pages, int nr)
  * lock getting page table operations atomic even if we drop the page
  * lock before returning.
  */
-struct page * lookup_swap_cache(swp_entry_t entry)
+struct page *lookup_swap_cache(swp_entry_t entry, struct vm_area_struct *vma,
+			       unsigned long addr)
 {
 	struct page *page;
+	unsigned long ra_info;
+	int win, hits, readahead;
 
 	page = find_get_page(swap_address_space(entry), swp_offset(entry));
 
-	if (page && likely(!PageTransCompound(page))) {
+	INC_CACHE_INFO(find_total);
+	if (page) {
 		INC_CACHE_INFO(find_success);
-		if (TestClearPageReadahead(page))
-			atomic_inc(&swapin_readahead_hits);
+		if (unlikely(PageTransCompound(page)))
+			return page;
+		readahead = TestClearPageReadahead(page);
+		if (vma) {
+			ra_info = GET_SWAP_RA_VAL(vma);
+			win = SWAP_RA_WIN(ra_info);
+			hits = SWAP_RA_HITS(ra_info);
+			if (readahead)
+				hits = min_t(int, hits + 1, SWAP_RA_HITS_MAX);
+			atomic_long_set(&vma->swap_readahead_info,
+					SWAP_RA_VAL(addr, win, hits));
+		}
+		if (readahead) {
+			count_vm_event(SWAP_RA_HIT);
+			if (!vma)
+				atomic_inc(&swapin_readahead_hits);
+		}
 	}
-
-	INC_CACHE_INFO(find_total);
 	return page;
 }
 
@@ -424,22 +464,20 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
 	return retpage;
 }
 
-static unsigned long swapin_nr_pages(unsigned long offset)
+static unsigned int __swapin_nr_pages(unsigned long prev_offset,
+				      unsigned long offset,
+				      int hits,
+				      int max_pages,
+				      int prev_win)
 {
-	static unsigned long prev_offset;
-	unsigned int pages, max_pages, last_ra;
-	static atomic_t last_readahead_pages;
-
-	max_pages = 1 << READ_ONCE(page_cluster);
-	if (max_pages <= 1)
-		return 1;
+	unsigned int pages, last_ra;
 
 	/*
 	 * This heuristic has been found to work well on both sequential and
 	 * random loads, swapping to hard disk or to SSD: please don't ask
 	 * what the "+ 2" means, it just happens to work well, that's all.
 	 */
-	pages = atomic_xchg(&swapin_readahead_hits, 0) + 2;
+	pages = hits + 2;
 	if (pages == 2) {
 		/*
 		 * We can have no readahead hits to judge by: but must not get
@@ -448,7 +486,6 @@ static unsigned long swapin_nr_pages(unsigned long offset)
 		 */
 		if (offset != prev_offset + 1 && offset != prev_offset - 1)
 			pages = 1;
-		prev_offset = offset;
 	} else {
 		unsigned int roundup = 4;
 		while (roundup < pages)
@@ -460,9 +497,28 @@ static unsigned long swapin_nr_pages(unsigned long offset)
 		pages = max_pages;
 
 	/* Don't shrink readahead too fast */
-	last_ra = atomic_read(&last_readahead_pages) / 2;
+	last_ra = prev_win / 2;
 	if (pages < last_ra)
 		pages = last_ra;
+
+	return pages;
+}
+
+static unsigned long swapin_nr_pages(unsigned long offset)
+{
+	static unsigned long prev_offset;
+	unsigned int hits, pages, max_pages;
+	static atomic_t last_readahead_pages;
+
+	max_pages = 1 << READ_ONCE(page_cluster);
+	if (max_pages <= 1)
+		return 1;
+
+	hits = atomic_xchg(&swapin_readahead_hits, 0);
+	pages = __swapin_nr_pages(prev_offset, offset, hits, max_pages,
+				  atomic_read(&last_readahead_pages));
+	if (!hits)
+		prev_offset = offset;
 	atomic_set(&last_readahead_pages, pages);
 
 	return pages;
@@ -496,7 +552,7 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
 	unsigned long start_offset, end_offset;
 	unsigned long mask;
 	struct blk_plug plug;
-	bool do_poll = true;
+	bool do_poll = true, page_allocated;
 
 	mask = swapin_nr_pages(offset) - 1;
 	if (!mask)
@@ -512,12 +568,19 @@ struct page *swapin_readahead(swp_entry_t entry, gfp_t gfp_mask,
 	blk_start_plug(&plug);
 	for (offset = start_offset; offset <= end_offset ; offset++) {
 		/* Ok, do the async read-ahead now */
-		page = read_swap_cache_async(swp_entry(swp_type(entry), offset),
-						gfp_mask, vma, addr, false);
+		page = __read_swap_cache_async(
+			swp_entry(swp_type(entry), offset),
+			gfp_mask, vma, addr, &page_allocated);
 		if (!page)
 			continue;
-		if (offset != entry_offset && likely(!PageTransCompound(page)))
-			SetPageReadahead(page);
+		if (page_allocated) {
+			swap_readpage(page, false);
+			if (offset != entry_offset &&
+			    likely(!PageTransCompound(page))) {
+				SetPageReadahead(page);
+				count_vm_event(SWAP_RA);
+			}
+		}
 		put_page(page);
 	}
 	blk_finish_plug(&plug);
@@ -561,3 +624,210 @@ void exit_swap_address_space(unsigned int type)
 	synchronize_rcu();
 	kvfree(spaces);
 }
+
+static inline void swap_ra_clamp_pfn(struct vm_area_struct *vma,
+				     unsigned long faddr,
+				     unsigned long lpfn,
+				     unsigned long rpfn,
+				     unsigned long *start,
+				     unsigned long *end)
+{
+	*start = max3(lpfn, PFN_DOWN(vma->vm_start),
+		      PFN_DOWN(faddr & PMD_MASK));
+	*end = min3(rpfn, PFN_DOWN(vma->vm_end),
+		    PFN_DOWN((faddr & PMD_MASK) + PMD_SIZE));
+}
+
+struct page *swap_readahead_detect(struct vm_fault *vmf,
+				   struct vma_swap_readahead *swap_ra)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	unsigned long swap_ra_info;
+	struct page *page;
+	swp_entry_t entry;
+	unsigned long faddr, pfn, fpfn;
+	unsigned long start, end;
+	pte_t *pte;
+	unsigned int max_win, hits, prev_win, win, left;
+#ifndef CONFIG_64BIT
+	pte_t *tpte;
+#endif
+
+	faddr = vmf->address;
+	entry = pte_to_swp_entry(vmf->orig_pte);
+	if ((unlikely(non_swap_entry(entry))))
+		return NULL;
+	page = lookup_swap_cache(entry, vma, faddr);
+	if (page)
+		return page;
+
+	max_win = 1 << READ_ONCE(swap_ra_max_order);
+	if (max_win == 1) {
+		swap_ra->win = 1;
+		return NULL;
+	}
+
+	fpfn = PFN_DOWN(faddr);
+	swap_ra_info = GET_SWAP_RA_VAL(vma);
+	pfn = PFN_DOWN(SWAP_RA_ADDR(swap_ra_info));
+	prev_win = SWAP_RA_WIN(swap_ra_info);
+	hits = SWAP_RA_HITS(swap_ra_info);
+	swap_ra->win = win = __swapin_nr_pages(pfn, fpfn, hits,
+					       max_win, prev_win);
+	atomic_long_set(&vma->swap_readahead_info,
+			SWAP_RA_VAL(faddr, win, 0));
+
+	if (win == 1)
+		return NULL;
+
+	/* Copy the PTEs because the page table may be unmapped */
+	if (fpfn == pfn + 1)
+		swap_ra_clamp_pfn(vma, faddr, fpfn, fpfn + win, &start, &end);
+	else if (pfn == fpfn + 1)
+		swap_ra_clamp_pfn(vma, faddr, fpfn - win + 1, fpfn + 1,
+				  &start, &end);
+	else {
+		left = (win - 1) / 2;
+		swap_ra_clamp_pfn(vma, faddr, fpfn - left, fpfn + win - left,
+				  &start, &end);
+	}
+	swap_ra->nr_pte = end - start;
+	swap_ra->offset = fpfn - start;
+	pte = vmf->pte - swap_ra->offset;
+#ifdef CONFIG_64BIT
+	swap_ra->ptes = pte;
+#else
+	tpte = swap_ra->ptes;
+	for (pfn = start; pfn != end; pfn++)
+		*tpte++ = *pte++;
+#endif
+
+	return NULL;
+}
+
+struct page *do_swap_page_readahead(swp_entry_t fentry, gfp_t gfp_mask,
+				    struct vm_fault *vmf,
+				    struct vma_swap_readahead *swap_ra)
+{
+	struct blk_plug plug;
+	struct vm_area_struct *vma = vmf->vma;
+	struct page *page;
+	pte_t *pte, pentry;
+	swp_entry_t entry;
+	unsigned int i;
+	bool page_allocated;
+
+	if (swap_ra->win == 1)
+		goto skip;
+
+	blk_start_plug(&plug);
+	for (i = 0, pte = swap_ra->ptes; i < swap_ra->nr_pte;
+	     i++, pte++) {
+		pentry = *pte;
+		if (pte_none(pentry))
+			continue;
+		if (pte_present(pentry))
+			continue;
+		entry = pte_to_swp_entry(pentry);
+		if (unlikely(non_swap_entry(entry)))
+			continue;
+		page = __read_swap_cache_async(entry, gfp_mask, vma,
+					       vmf->address, &page_allocated);
+		if (!page)
+			continue;
+		if (page_allocated) {
+			swap_readpage(page, false);
+			if (i != swap_ra->offset &&
+			    likely(!PageTransCompound(page))) {
+				SetPageReadahead(page);
+				count_vm_event(SWAP_RA);
+			}
+		}
+		put_page(page);
+	}
+	blk_finish_plug(&plug);
+	lru_add_drain();
+skip:
+	return read_swap_cache_async(fentry, gfp_mask, vma, vmf->address,
+				     swap_ra->win == 1);
+}
+
+#ifdef CONFIG_SYSFS
+static ssize_t vma_ra_enabled_show(struct kobject *kobj,
+				     struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%s\n", swap_vma_readahead ? "true" : "false");
+}
+static ssize_t vma_ra_enabled_store(struct kobject *kobj,
+				      struct kobj_attribute *attr,
+				      const char *buf, size_t count)
+{
+	if (!strncmp(buf, "true", 4) || !strncmp(buf, "1", 1))
+		swap_vma_readahead = true;
+	else if (!strncmp(buf, "false", 5) || !strncmp(buf, "0", 1))
+		swap_vma_readahead = false;
+	else
+		return -EINVAL;
+
+	return count;
+}
+static struct kobj_attribute vma_ra_enabled_attr =
+	__ATTR(vma_ra_enabled, 0644, vma_ra_enabled_show,
+	       vma_ra_enabled_store);
+
+static ssize_t vma_ra_max_order_show(struct kobject *kobj,
+				     struct kobj_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", swap_ra_max_order);
+}
+static ssize_t vma_ra_max_order_store(struct kobject *kobj,
+				      struct kobj_attribute *attr,
+				      const char *buf, size_t count)
+{
+	int err, v;
+
+	err = kstrtoint(buf, 10, &v);
+	if (err || v > SWAP_RA_ORDER_CEILING || v <= 0)
+		return -EINVAL;
+
+	swap_ra_max_order = v;
+
+	return count;
+}
+static struct kobj_attribute vma_ra_max_order_attr =
+	__ATTR(vma_ra_max_order, 0644, vma_ra_max_order_show,
+	       vma_ra_max_order_store);
+
+static struct attribute *swap_attrs[] = {
+	&vma_ra_enabled_attr.attr,
+	&vma_ra_max_order_attr.attr,
+	NULL,
+};
+
+static struct attribute_group swap_attr_group = {
+	.attrs = swap_attrs,
+};
+
+static int __init swap_init_sysfs(void)
+{
+	int err;
+	struct kobject *swap_kobj;
+
+	swap_kobj = kobject_create_and_add("swap", mm_kobj);
+	if (!swap_kobj) {
+		pr_err("failed to create swap kobject\n");
+		return -ENOMEM;
+	}
+	err = sysfs_create_group(swap_kobj, &swap_attr_group);
+	if (err) {
+		pr_err("failed to register swap group\n");
+		goto delete_obj;
+	}
+	return 0;
+
+delete_obj:
+	kobject_put(swap_kobj);
+	return err;
+}
+subsys_initcall(swap_init_sysfs);
+#endif
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 6ba4aab2db0b..d483278ee35b 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -60,7 +60,7 @@ atomic_long_t nr_swap_pages;
 EXPORT_SYMBOL_GPL(nr_swap_pages);
 /* protected with swap_lock. reading in vm_swap_full() doesn't need lock */
 long total_swap_pages;
-static int least_priority;
+static int least_priority = -1;
 
 static const char Bad_file[] = "Bad swap file entry ";
 static const char Unused_file[] = "Unused swap file entry ";
@@ -85,7 +85,7 @@ PLIST_HEAD(swap_active_head);
  * is held and the locking order requires swap_lock to be taken
  * before any swap_info_struct->lock.
  */
-static PLIST_HEAD(swap_avail_head);
+struct plist_head *swap_avail_heads;
 static DEFINE_SPINLOCK(swap_avail_lock);
 
 struct swap_info_struct *swap_info[MAX_SWAPFILES];
@@ -96,6 +96,8 @@ static DECLARE_WAIT_QUEUE_HEAD(proc_poll_wait);
 /* Activity counter to indicate that a swapon or swapoff has occurred */
 static atomic_t proc_poll_event = ATOMIC_INIT(0);
 
+atomic_t nr_rotate_swap = ATOMIC_INIT(0);
+
 static inline unsigned char swap_count(unsigned char ent)
 {
 	return ent & ~SWAP_HAS_CACHE;	/* may include SWAP_HAS_CONT flag */
@@ -265,6 +267,16 @@ static inline void cluster_set_null(struct swap_cluster_info *info)
 	info->data = 0;
 }
 
+static inline bool cluster_is_huge(struct swap_cluster_info *info)
+{
+	return info->flags & CLUSTER_FLAG_HUGE;
+}
+
+static inline void cluster_clear_huge(struct swap_cluster_info *info)
+{
+	info->flags &= ~CLUSTER_FLAG_HUGE;
+}
+
 static inline struct swap_cluster_info *lock_cluster(struct swap_info_struct *si,
 						     unsigned long offset)
 {
@@ -580,6 +592,21 @@ new_cluster:
 	return found_free;
 }
 
+static void __del_from_avail_list(struct swap_info_struct *p)
+{
+	int nid;
+
+	for_each_node(nid)
+		plist_del(&p->avail_lists[nid], &swap_avail_heads[nid]);
+}
+
+static void del_from_avail_list(struct swap_info_struct *p)
+{
+	spin_lock(&swap_avail_lock);
+	__del_from_avail_list(p);
+	spin_unlock(&swap_avail_lock);
+}
+
 static void swap_range_alloc(struct swap_info_struct *si, unsigned long offset,
 			     unsigned int nr_entries)
 {
@@ -593,10 +620,20 @@ static void swap_range_alloc(struct swap_info_struct *si, unsigned long offset,
 	if (si->inuse_pages == si->pages) {
 		si->lowest_bit = si->max;
 		si->highest_bit = 0;
-		spin_lock(&swap_avail_lock);
-		plist_del(&si->avail_list, &swap_avail_head);
-		spin_unlock(&swap_avail_lock);
+		del_from_avail_list(si);
+	}
+}
+
+static void add_to_avail_list(struct swap_info_struct *p)
+{
+	int nid;
+
+	spin_lock(&swap_avail_lock);
+	for_each_node(nid) {
+		WARN_ON(!plist_node_empty(&p->avail_lists[nid]));
+		plist_add(&p->avail_lists[nid], &swap_avail_heads[nid]);
 	}
+	spin_unlock(&swap_avail_lock);
 }
 
 static void swap_range_free(struct swap_info_struct *si, unsigned long offset,
@@ -611,13 +648,8 @@ static void swap_range_free(struct swap_info_struct *si, unsigned long offset,
 		bool was_full = !si->highest_bit;
 
 		si->highest_bit = end;
-		if (was_full && (si->flags & SWP_WRITEOK)) {
-			spin_lock(&swap_avail_lock);
-			WARN_ON(!plist_node_empty(&si->avail_list));
-			if (plist_node_empty(&si->avail_list))
-				plist_add(&si->avail_list, &swap_avail_head);
-			spin_unlock(&swap_avail_lock);
-		}
+		if (was_full && (si->flags & SWP_WRITEOK))
+			add_to_avail_list(si);
 	}
 	atomic_long_add(nr_entries, &nr_swap_pages);
 	si->inuse_pages -= nr_entries;
@@ -846,7 +878,7 @@ static int swap_alloc_cluster(struct swap_info_struct *si, swp_entry_t *slot)
 	offset = idx * SWAPFILE_CLUSTER;
 	ci = lock_cluster(si, offset);
 	alloc_cluster(si, idx);
-	cluster_set_count_flag(ci, SWAPFILE_CLUSTER, 0);
+	cluster_set_count_flag(ci, SWAPFILE_CLUSTER, CLUSTER_FLAG_HUGE);
 
 	map = si->swap_map + offset;
 	for (i = 0; i < SWAPFILE_CLUSTER; i++)
@@ -898,6 +930,7 @@ int get_swap_pages(int n_goal, bool cluster, swp_entry_t swp_entries[])
 	struct swap_info_struct *si, *next;
 	long avail_pgs;
 	int n_ret = 0;
+	int node;
 
 	/* Only single cluster request supported */
 	WARN_ON_ONCE(n_goal > 1 && cluster);
@@ -917,14 +950,15 @@ int get_swap_pages(int n_goal, bool cluster, swp_entry_t swp_entries[])
 	spin_lock(&swap_avail_lock);
 
 start_over:
-	plist_for_each_entry_safe(si, next, &swap_avail_head, avail_list) {
+	node = numa_node_id();
+	plist_for_each_entry_safe(si, next, &swap_avail_heads[node], avail_lists[node]) {
 		/* requeue si to after same-priority siblings */
-		plist_requeue(&si->avail_list, &swap_avail_head);
+		plist_requeue(&si->avail_lists[node], &swap_avail_heads[node]);
 		spin_unlock(&swap_avail_lock);
 		spin_lock(&si->lock);
 		if (!si->highest_bit || !(si->flags & SWP_WRITEOK)) {
 			spin_lock(&swap_avail_lock);
-			if (plist_node_empty(&si->avail_list)) {
+			if (plist_node_empty(&si->avail_lists[node])) {
 				spin_unlock(&si->lock);
 				goto nextsi;
 			}
@@ -934,13 +968,14 @@ start_over:
 			WARN(!(si->flags & SWP_WRITEOK),
 			     "swap_info %d in list but !SWP_WRITEOK\n",
 			     si->type);
-			plist_del(&si->avail_list, &swap_avail_head);
+			__del_from_avail_list(si);
 			spin_unlock(&si->lock);
 			goto nextsi;
 		}
-		if (cluster)
-			n_ret = swap_alloc_cluster(si, swp_entries);
-		else
+		if (cluster) {
+			if (!(si->flags & SWP_FILE))
+				n_ret = swap_alloc_cluster(si, swp_entries);
+		} else
 			n_ret = scan_swap_map_slots(si, SWAP_HAS_CACHE,
 						    n_goal, swp_entries);
 		spin_unlock(&si->lock);
@@ -962,7 +997,7 @@ nextsi:
 		 * swap_avail_head list then try it, otherwise start over
 		 * if we have not gotten any slots.
 		 */
-		if (plist_node_empty(&next->avail_list))
+		if (plist_node_empty(&next->avail_lists[node]))
 			goto start_over;
 	}
 
@@ -1168,22 +1203,57 @@ static void swapcache_free_cluster(swp_entry_t entry)
 	struct swap_cluster_info *ci;
 	struct swap_info_struct *si;
 	unsigned char *map;
-	unsigned int i;
+	unsigned int i, free_entries = 0;
+	unsigned char val;
 
-	si = swap_info_get(entry);
+	si = _swap_info_get(entry);
 	if (!si)
 		return;
 
 	ci = lock_cluster(si, offset);
+	VM_BUG_ON(!cluster_is_huge(ci));
 	map = si->swap_map + offset;
 	for (i = 0; i < SWAPFILE_CLUSTER; i++) {
-		VM_BUG_ON(map[i] != SWAP_HAS_CACHE);
-		map[i] = 0;
+		val = map[i];
+		VM_BUG_ON(!(val & SWAP_HAS_CACHE));
+		if (val == SWAP_HAS_CACHE)
+			free_entries++;
+	}
+	if (!free_entries) {
+		for (i = 0; i < SWAPFILE_CLUSTER; i++)
+			map[i] &= ~SWAP_HAS_CACHE;
 	}
+	cluster_clear_huge(ci);
 	unlock_cluster(ci);
-	mem_cgroup_uncharge_swap(entry, SWAPFILE_CLUSTER);
-	swap_free_cluster(si, idx);
-	spin_unlock(&si->lock);
+	if (free_entries == SWAPFILE_CLUSTER) {
+		spin_lock(&si->lock);
+		ci = lock_cluster(si, offset);
+		memset(map, 0, SWAPFILE_CLUSTER);
+		unlock_cluster(ci);
+		mem_cgroup_uncharge_swap(entry, SWAPFILE_CLUSTER);
+		swap_free_cluster(si, idx);
+		spin_unlock(&si->lock);
+	} else if (free_entries) {
+		for (i = 0; i < SWAPFILE_CLUSTER; i++, entry.val++) {
+			if (!__swap_entry_free(si, entry, SWAP_HAS_CACHE))
+				free_swap_slot(entry);
+		}
+	}
+}
+
+int split_swap_cluster(swp_entry_t entry)
+{
+	struct swap_info_struct *si;
+	struct swap_cluster_info *ci;
+	unsigned long offset = swp_offset(entry);
+
+	si = _swap_info_get(entry);
+	if (!si)
+		return -EBUSY;
+	ci = lock_cluster(si, offset);
+	cluster_clear_huge(ci);
+	unlock_cluster(ci);
+	return 0;
 }
 #else
 static inline void swapcache_free_cluster(swp_entry_t entry)
@@ -1332,29 +1402,161 @@ out:
 	return count;
 }
 
+#ifdef CONFIG_THP_SWAP
+static bool swap_page_trans_huge_swapped(struct swap_info_struct *si,
+					 swp_entry_t entry)
+{
+	struct swap_cluster_info *ci;
+	unsigned char *map = si->swap_map;
+	unsigned long roffset = swp_offset(entry);
+	unsigned long offset = round_down(roffset, SWAPFILE_CLUSTER);
+	int i;
+	bool ret = false;
+
+	ci = lock_cluster_or_swap_info(si, offset);
+	if (!ci || !cluster_is_huge(ci)) {
+		if (map[roffset] != SWAP_HAS_CACHE)
+			ret = true;
+		goto unlock_out;
+	}
+	for (i = 0; i < SWAPFILE_CLUSTER; i++) {
+		if (map[offset + i] != SWAP_HAS_CACHE) {
+			ret = true;
+			break;
+		}
+	}
+unlock_out:
+	unlock_cluster_or_swap_info(si, ci);
+	return ret;
+}
+
+static bool page_swapped(struct page *page)
+{
+	swp_entry_t entry;
+	struct swap_info_struct *si;
+
+	if (likely(!PageTransCompound(page)))
+		return page_swapcount(page) != 0;
+
+	page = compound_head(page);
+	entry.val = page_private(page);
+	si = _swap_info_get(entry);
+	if (si)
+		return swap_page_trans_huge_swapped(si, entry);
+	return false;
+}
+
+static int page_trans_huge_map_swapcount(struct page *page, int *total_mapcount,
+					 int *total_swapcount)
+{
+	int i, map_swapcount, _total_mapcount, _total_swapcount;
+	unsigned long offset = 0;
+	struct swap_info_struct *si;
+	struct swap_cluster_info *ci = NULL;
+	unsigned char *map = NULL;
+	int mapcount, swapcount = 0;
+
+	/* hugetlbfs shouldn't call it */
+	VM_BUG_ON_PAGE(PageHuge(page), page);
+
+	if (likely(!PageTransCompound(page))) {
+		mapcount = atomic_read(&page->_mapcount) + 1;
+		if (total_mapcount)
+			*total_mapcount = mapcount;
+		if (PageSwapCache(page))
+			swapcount = page_swapcount(page);
+		if (total_swapcount)
+			*total_swapcount = swapcount;
+		return mapcount + swapcount;
+	}
+
+	page = compound_head(page);
+
+	_total_mapcount = _total_swapcount = map_swapcount = 0;
+	if (PageSwapCache(page)) {
+		swp_entry_t entry;
+
+		entry.val = page_private(page);
+		si = _swap_info_get(entry);
+		if (si) {
+			map = si->swap_map;
+			offset = swp_offset(entry);
+		}
+	}
+	if (map)
+		ci = lock_cluster(si, offset);
+	for (i = 0; i < HPAGE_PMD_NR; i++) {
+		mapcount = atomic_read(&page[i]._mapcount) + 1;
+		_total_mapcount += mapcount;
+		if (map) {
+			swapcount = swap_count(map[offset + i]);
+			_total_swapcount += swapcount;
+		}
+		map_swapcount = max(map_swapcount, mapcount + swapcount);
+	}
+	unlock_cluster(ci);
+	if (PageDoubleMap(page)) {
+		map_swapcount -= 1;
+		_total_mapcount -= HPAGE_PMD_NR;
+	}
+	mapcount = compound_mapcount(page);
+	map_swapcount += mapcount;
+	_total_mapcount += mapcount;
+	if (total_mapcount)
+		*total_mapcount = _total_mapcount;
+	if (total_swapcount)
+		*total_swapcount = _total_swapcount;
+
+	return map_swapcount;
+}
+#else
+#define swap_page_trans_huge_swapped(si, entry)	swap_swapcount(si, entry)
+#define page_swapped(page)			(page_swapcount(page) != 0)
+
+static int page_trans_huge_map_swapcount(struct page *page, int *total_mapcount,
+					 int *total_swapcount)
+{
+	int mapcount, swapcount = 0;
+
+	/* hugetlbfs shouldn't call it */
+	VM_BUG_ON_PAGE(PageHuge(page), page);
+
+	mapcount = page_trans_huge_mapcount(page, total_mapcount);
+	if (PageSwapCache(page))
+		swapcount = page_swapcount(page);
+	if (total_swapcount)
+		*total_swapcount = swapcount;
+	return mapcount + swapcount;
+}
+#endif
+
 /*
  * 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
  * later would only waste time away from clustering.
  *
- * NOTE: total_mapcount should not be relied upon by the caller if
+ * NOTE: total_map_swapcount should not be relied upon by the caller if
  * reuse_swap_page() returns false, but it may be always overwritten
  * (see the other implementation for CONFIG_SWAP=n).
  */
-bool reuse_swap_page(struct page *page, int *total_mapcount)
+bool reuse_swap_page(struct page *page, int *total_map_swapcount)
 {
-	int count;
+	int count, total_mapcount, total_swapcount;
 
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	if (unlikely(PageKsm(page)))
 		return false;
-	count = page_trans_huge_mapcount(page, total_mapcount);
-	if (count <= 1 && PageSwapCache(page)) {
-		count += page_swapcount(page);
-		if (count != 1)
-			goto out;
+	count = page_trans_huge_map_swapcount(page, &total_mapcount,
+					      &total_swapcount);
+	if (total_map_swapcount)
+		*total_map_swapcount = total_mapcount + total_swapcount;
+	if (count == 1 && PageSwapCache(page) &&
+	    (likely(!PageTransCompound(page)) ||
+	     /* The remaining swap count will be freed soon */
+	     total_swapcount == page_swapcount(page))) {
 		if (!PageWriteback(page)) {
+			page = compound_head(page);
 			delete_from_swap_cache(page);
 			SetPageDirty(page);
 		} else {
@@ -1370,7 +1572,7 @@ bool reuse_swap_page(struct page *page, int *total_mapcount)
 			spin_unlock(&p->lock);
 		}
 	}
-out:
+
 	return count <= 1;
 }
 
@@ -1386,7 +1588,7 @@ int try_to_free_swap(struct page *page)
 		return 0;
 	if (PageWriteback(page))
 		return 0;
-	if (page_swapcount(page))
+	if (page_swapped(page))
 		return 0;
 
 	/*
@@ -1407,6 +1609,7 @@ int try_to_free_swap(struct page *page)
 	if (pm_suspended_storage())
 		return 0;
 
+	page = compound_head(page);
 	delete_from_swap_cache(page);
 	SetPageDirty(page);
 	return 1;
@@ -1428,7 +1631,8 @@ int free_swap_and_cache(swp_entry_t entry)
 	p = _swap_info_get(entry);
 	if (p) {
 		count = __swap_entry_free(p, entry, 1);
-		if (count == SWAP_HAS_CACHE) {
+		if (count == SWAP_HAS_CACHE &&
+		    !swap_page_trans_huge_swapped(p, entry)) {
 			page = find_get_page(swap_address_space(entry),
 					     swp_offset(entry));
 			if (page && !trylock_page(page)) {
@@ -1445,7 +1649,8 @@ int free_swap_and_cache(swp_entry_t entry)
 		 */
 		if (PageSwapCache(page) && !PageWriteback(page) &&
 		    (!page_mapped(page) || mem_cgroup_swap_full(page)) &&
-		    !swap_swapcount(p, entry)) {
+		    !swap_page_trans_huge_swapped(p, entry)) {
+			page = compound_head(page);
 			delete_from_swap_cache(page);
 			SetPageDirty(page);
 		}
@@ -1999,7 +2204,7 @@ int try_to_unuse(unsigned int type, bool frontswap,
 				.sync_mode = WB_SYNC_NONE,
 			};
 
-			swap_writepage(page, &wbc);
+			swap_writepage(compound_head(page), &wbc);
 			lock_page(page);
 			wait_on_page_writeback(page);
 		}
@@ -2012,8 +2217,9 @@ int try_to_unuse(unsigned int type, bool frontswap,
 		 * delete, since it may not have been written out to swap yet.
 		 */
 		if (PageSwapCache(page) &&
-		    likely(page_private(page) == entry.val))
-			delete_from_swap_cache(page);
+		    likely(page_private(page) == entry.val) &&
+		    !page_swapped(page))
+			delete_from_swap_cache(compound_head(page));
 
 		/*
 		 * So we could skip searching mms once swap count went
@@ -2226,10 +2432,24 @@ static int setup_swap_extents(struct swap_info_struct *sis, sector_t *span)
 	return generic_swapfile_activate(sis, swap_file, span);
 }
 
+static int swap_node(struct swap_info_struct *p)
+{
+	struct block_device *bdev;
+
+	if (p->bdev)
+		bdev = p->bdev;
+	else
+		bdev = p->swap_file->f_inode->i_sb->s_bdev;
+
+	return bdev ? bdev->bd_disk->node_id : NUMA_NO_NODE;
+}
+
 static void _enable_swap_info(struct swap_info_struct *p, int prio,
 				unsigned char *swap_map,
 				struct swap_cluster_info *cluster_info)
 {
+	int i;
+
 	if (prio >= 0)
 		p->prio = prio;
 	else
@@ -2239,7 +2459,16 @@ static void _enable_swap_info(struct swap_info_struct *p, int prio,
 	 * low-to-high, while swap ordering is high-to-low
 	 */
 	p->list.prio = -p->prio;
-	p->avail_list.prio = -p->prio;
+	for_each_node(i) {
+		if (p->prio >= 0)
+			p->avail_lists[i].prio = -p->prio;
+		else {
+			if (swap_node(p) == i)
+				p->avail_lists[i].prio = 1;
+			else
+				p->avail_lists[i].prio = -p->prio;
+		}
+	}
 	p->swap_map = swap_map;
 	p->cluster_info = cluster_info;
 	p->flags |= SWP_WRITEOK;
@@ -2258,9 +2487,7 @@ static void _enable_swap_info(struct swap_info_struct *p, int prio,
 	 * swap_info_struct.
 	 */
 	plist_add(&p->list, &swap_active_head);
-	spin_lock(&swap_avail_lock);
-	plist_add(&p->avail_list, &swap_avail_head);
-	spin_unlock(&swap_avail_lock);
+	add_to_avail_list(p);
 }
 
 static void enable_swap_info(struct swap_info_struct *p, int prio,
@@ -2345,17 +2572,19 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 		spin_unlock(&swap_lock);
 		goto out_dput;
 	}
-	spin_lock(&swap_avail_lock);
-	plist_del(&p->avail_list, &swap_avail_head);
-	spin_unlock(&swap_avail_lock);
+	del_from_avail_list(p);
 	spin_lock(&p->lock);
 	if (p->prio < 0) {
 		struct swap_info_struct *si = p;
+		int nid;
 
 		plist_for_each_entry_continue(si, &swap_active_head, list) {
 			si->prio++;
 			si->list.prio--;
-			si->avail_list.prio--;
+			for_each_node(nid) {
+				if (si->avail_lists[nid].prio != 1)
+					si->avail_lists[nid].prio--;
+			}
 		}
 		least_priority++;
 	}
@@ -2387,6 +2616,9 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 	if (p->flags & SWP_CONTINUED)
 		free_swap_count_continuations(p);
 
+	if (!p->bdev || !blk_queue_nonrot(bdev_get_queue(p->bdev)))
+		atomic_dec(&nr_rotate_swap);
+
 	mutex_lock(&swapon_mutex);
 	spin_lock(&swap_lock);
 	spin_lock(&p->lock);
@@ -2596,6 +2828,7 @@ static struct swap_info_struct *alloc_swap_info(void)
 {
 	struct swap_info_struct *p;
 	unsigned int type;
+	int i;
 
 	p = kzalloc(sizeof(*p), GFP_KERNEL);
 	if (!p)
@@ -2631,7 +2864,8 @@ static struct swap_info_struct *alloc_swap_info(void)
 	}
 	INIT_LIST_HEAD(&p->first_swap_extent.list);
 	plist_node_init(&p->list, 0);
-	plist_node_init(&p->avail_list, 0);
+	for_each_node(i)
+		plist_node_init(&p->avail_lists[i], 0);
 	p->flags = SWP_USED;
 	spin_unlock(&swap_lock);
 	spin_lock_init(&p->lock);
@@ -2873,6 +3107,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
+	if (!swap_avail_heads)
+		return -ENOMEM;
+
 	p = alloc_swap_info();
 	if (IS_ERR(p))
 		return PTR_ERR(p);
@@ -2963,7 +3200,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 			cluster = per_cpu_ptr(p->percpu_cluster, cpu);
 			cluster_set_null(&cluster->index);
 		}
-	}
+	} else
+		atomic_inc(&nr_rotate_swap);
 
 	error = swap_cgroup_swapon(p->type, maxpages);
 	if (error)
@@ -3457,3 +3695,21 @@ static void free_swap_count_continuations(struct swap_info_struct *si)
 		}
 	}
 }
+
+static int __init swapfile_init(void)
+{
+	int nid;
+
+	swap_avail_heads = kmalloc_array(nr_node_ids, sizeof(struct plist_head),
+					 GFP_KERNEL);
+	if (!swap_avail_heads) {
+		pr_emerg("Not enough memory for swap heads, swap is disabled\n");
+		return -ENOMEM;
+	}
+
+	for_each_node(nid)
+		plist_head_init(&swap_avail_heads[nid]);
+
+	return 0;
+}
+subsys_initcall(swapfile_init);
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 8bcb501bce60..81192701964d 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -371,6 +371,36 @@ extern ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
 				      bool zeropage);
 #endif /* CONFIG_HUGETLB_PAGE */
 
+static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm,
+						pmd_t *dst_pmd,
+						struct vm_area_struct *dst_vma,
+						unsigned long dst_addr,
+						unsigned long src_addr,
+						struct page **page,
+						bool zeropage)
+{
+	ssize_t err;
+
+	if (vma_is_anonymous(dst_vma)) {
+		if (!zeropage)
+			err = mcopy_atomic_pte(dst_mm, dst_pmd, dst_vma,
+					       dst_addr, src_addr, page);
+		else
+			err = mfill_zeropage_pte(dst_mm, dst_pmd,
+						 dst_vma, dst_addr);
+	} else {
+		if (!zeropage)
+			err = shmem_mcopy_atomic_pte(dst_mm, dst_pmd,
+						     dst_vma, dst_addr,
+						     src_addr, page);
+		else
+			err = shmem_mfill_zeropage_pte(dst_mm, dst_pmd,
+						       dst_vma, dst_addr);
+	}
+
+	return err;
+}
+
 static __always_inline ssize_t __mcopy_atomic(struct mm_struct *dst_mm,
 					      unsigned long dst_start,
 					      unsigned long src_start,
@@ -487,22 +517,8 @@ retry:
 		BUG_ON(pmd_none(*dst_pmd));
 		BUG_ON(pmd_trans_huge(*dst_pmd));
 
-		if (vma_is_anonymous(dst_vma)) {
-			if (!zeropage)
-				err = mcopy_atomic_pte(dst_mm, dst_pmd, dst_vma,
-						       dst_addr, src_addr,
-						       &page);
-			else
-				err = mfill_zeropage_pte(dst_mm, dst_pmd,
-							 dst_vma, dst_addr);
-		} else {
-			err = -EINVAL; /* if zeropage is true return -EINVAL */
-			if (likely(!zeropage))
-				err = shmem_mcopy_atomic_pte(dst_mm, dst_pmd,
-							     dst_vma, dst_addr,
-							     src_addr, &page);
-		}
-
+		err = mfill_atomic_pte(dst_mm, dst_pmd, dst_vma, dst_addr,
+				       src_addr, &page, zeropage);
 		cond_resched();
 
 		if (unlikely(err == -EFAULT)) {
diff --git a/mm/util.c b/mm/util.c
index 9ecddf568fe3..34e57fae959d 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -614,7 +614,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
 		return 0;
 
 	if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
-		free = global_page_state(NR_FREE_PAGES);
+		free = global_zone_page_state(NR_FREE_PAGES);
 		free += global_node_page_state(NR_FILE_PAGES);
 
 		/*
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index a47e3894c775..8a43db6284eb 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -49,12 +49,10 @@ static void __vunmap(const void *, int);
 static void free_work(struct work_struct *w)
 {
 	struct vfree_deferred *p = container_of(w, struct vfree_deferred, wq);
-	struct llist_node *llnode = llist_del_all(&p->list);
-	while (llnode) {
-		void *p = llnode;
-		llnode = llist_next(llnode);
-		__vunmap(p, 1);
-	}
+	struct llist_node *t, *llnode;
+
+	llist_for_each_safe(llnode, t, llist_del_all(&p->list))
+		__vunmap((void *)llnode, 1);
 }
 
 /*** Page table manipulation functions ***/
@@ -2482,7 +2480,7 @@ static unsigned long pvm_determine_end(struct vmap_area **pnext,
  * matching slot.  While scanning, if any of the areas overlaps with
  * existing vmap_area, the base address is pulled down to fit the
  * area.  Scanning is repeated till all the areas fit and then all
- * necessary data structres are inserted and the result is returned.
+ * necessary data structures are inserted and the result is returned.
  */
 struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
 				     const size_t *sizes, int nr_vms,
@@ -2510,15 +2508,11 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
 		if (start > offsets[last_area])
 			last_area = area;
 
-		for (area2 = 0; area2 < nr_vms; area2++) {
+		for (area2 = area + 1; area2 < nr_vms; area2++) {
 			unsigned long start2 = offsets[area2];
 			unsigned long end2 = start2 + sizes[area2];
 
-			if (area2 == area)
-				continue;
-
-			BUG_ON(start2 >= start && start2 < end);
-			BUG_ON(end2 <= end && end2 > start);
+			BUG_ON(start2 < end && start < end2);
 		}
 	}
 	last_end = offsets[last_area] + sizes[last_area];
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f957afe900ec..13d711dd8776 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -393,14 +393,15 @@ static unsigned long do_shrink_slab(struct shrink_control *shrinkctl,
 		unsigned long nr_to_scan = min(batch_size, total_scan);
 
 		shrinkctl->nr_to_scan = nr_to_scan;
+		shrinkctl->nr_scanned = nr_to_scan;
 		ret = shrinker->scan_objects(shrinker, shrinkctl);
 		if (ret == SHRINK_STOP)
 			break;
 		freed += ret;
 
-		count_vm_events(SLABS_SCANNED, nr_to_scan);
-		total_scan -= nr_to_scan;
-		scanned += nr_to_scan;
+		count_vm_events(SLABS_SCANNED, shrinkctl->nr_scanned);
+		total_scan -= shrinkctl->nr_scanned;
+		scanned += shrinkctl->nr_scanned;
 
 		cond_resched();
 	}
@@ -535,7 +536,9 @@ static inline int is_page_cache_freeable(struct page *page)
 	 * that isolated the page, the page cache radix tree and
 	 * optional buffer heads at page->private.
 	 */
-	return page_count(page) - page_has_private(page) == 2;
+	int radix_pins = PageTransHuge(page) && PageSwapCache(page) ?
+		HPAGE_PMD_NR : 1;
+	return page_count(page) - page_has_private(page) == 1 + radix_pins;
 }
 
 static int may_write_to_inode(struct inode *inode, struct scan_control *sc)
@@ -665,6 +668,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
 			    bool reclaimed)
 {
 	unsigned long flags;
+	int refcount;
 
 	BUG_ON(!PageLocked(page));
 	BUG_ON(mapping != page_mapping(page));
@@ -695,11 +699,15 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
 	 * Note that if SetPageDirty is always performed via set_page_dirty,
 	 * and thus under tree_lock, then this ordering is not required.
 	 */
-	if (!page_ref_freeze(page, 2))
+	if (unlikely(PageTransHuge(page)) && PageSwapCache(page))
+		refcount = 1 + HPAGE_PMD_NR;
+	else
+		refcount = 2;
+	if (!page_ref_freeze(page, refcount))
 		goto cannot_free;
 	/* note: atomic_cmpxchg in page_freeze_refs provides the smp_rmb */
 	if (unlikely(PageDirty(page))) {
-		page_ref_unfreeze(page, 2);
+		page_ref_unfreeze(page, refcount);
 		goto cannot_free;
 	}
 
@@ -1121,58 +1129,59 @@ static unsigned long shrink_page_list(struct list_head *page_list,
 		 * Try to allocate it some swap space here.
 		 * Lazyfree page could be freed directly
 		 */
-		if (PageAnon(page) && PageSwapBacked(page) &&
-		    !PageSwapCache(page)) {
-			if (!(sc->gfp_mask & __GFP_IO))
-				goto keep_locked;
-			if (PageTransHuge(page)) {
-				/* cannot split THP, skip it */
-				if (!can_split_huge_page(page, NULL))
-					goto activate_locked;
-				/*
-				 * Split pages without a PMD map right
-				 * away. Chances are some or all of the
-				 * tail pages can be freed without IO.
-				 */
-				if (!compound_mapcount(page) &&
-				    split_huge_page_to_list(page, page_list))
-					goto activate_locked;
-			}
-			if (!add_to_swap(page)) {
-				if (!PageTransHuge(page))
-					goto activate_locked;
-				/* Split THP and swap individual base pages */
-				if (split_huge_page_to_list(page, page_list))
-					goto activate_locked;
-				if (!add_to_swap(page))
-					goto activate_locked;
-			}
-
-			/* XXX: We don't support THP writes */
-			if (PageTransHuge(page) &&
-				  split_huge_page_to_list(page, page_list)) {
-				delete_from_swap_cache(page);
-				goto activate_locked;
-			}
+		if (PageAnon(page) && PageSwapBacked(page)) {
+			if (!PageSwapCache(page)) {
+				if (!(sc->gfp_mask & __GFP_IO))
+					goto keep_locked;
+				if (PageTransHuge(page)) {
+					/* cannot split THP, skip it */
+					if (!can_split_huge_page(page, NULL))
+						goto activate_locked;
+					/*
+					 * Split pages without a PMD map right
+					 * away. Chances are some or all of the
+					 * tail pages can be freed without IO.
+					 */
+					if (!compound_mapcount(page) &&
+					    split_huge_page_to_list(page,
+								    page_list))
+						goto activate_locked;
+				}
+				if (!add_to_swap(page)) {
+					if (!PageTransHuge(page))
+						goto activate_locked;
+					/* Fallback to swap normal pages */
+					if (split_huge_page_to_list(page,
+								    page_list))
+						goto activate_locked;
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+					count_vm_event(THP_SWPOUT_FALLBACK);
+#endif
+					if (!add_to_swap(page))
+						goto activate_locked;
+				}
 
-			may_enter_fs = 1;
+				may_enter_fs = 1;
 
-			/* Adding to swap updated mapping */
-			mapping = page_mapping(page);
+				/* Adding to swap updated mapping */
+				mapping = page_mapping(page);
+			}
 		} else if (unlikely(PageTransHuge(page))) {
 			/* Split file THP */
 			if (split_huge_page_to_list(page, page_list))
 				goto keep_locked;
 		}
 
-		VM_BUG_ON_PAGE(PageTransHuge(page), page);
-
 		/*
 		 * The page is mapped into the page tables of one or more
 		 * processes. Try to unmap it here.
 		 */
 		if (page_mapped(page)) {
-			if (!try_to_unmap(page, ttu_flags | TTU_BATCH_FLUSH)) {
+			enum ttu_flags flags = ttu_flags | TTU_BATCH_FLUSH;
+
+			if (unlikely(PageTransHuge(page)))
+				flags |= TTU_SPLIT_HUGE_PMD;
+			if (!try_to_unmap(page, flags)) {
 				nr_unmap_fail++;
 				goto activate_locked;
 			}
@@ -1312,7 +1321,11 @@ free_it:
 		 * Is there need to periodically free_page_list? It would
 		 * appear not as the counts should be low
 		 */
-		list_add(&page->lru, &free_pages);
+		if (unlikely(PageTransHuge(page))) {
+			mem_cgroup_uncharge(page);
+			(*get_compound_page_dtor(page))(page);
+		} else
+			list_add(&page->lru, &free_pages);
 		continue;
 
 activate_locked:
@@ -1742,9 +1755,15 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 	int file = is_file_lru(lru);
 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
 	struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
+	bool stalled = false;
 
 	while (unlikely(too_many_isolated(pgdat, file, sc))) {
-		congestion_wait(BLK_RW_ASYNC, HZ/10);
+		if (stalled)
+			return 0;
+
+		/* wait a bit for the reclaimer. */
+		msleep(100);
+		stalled = true;
 
 		/* We are about to die and free our memory. Return now. */
 		if (fatal_signal_pending(current))
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 9a4441bbeef2..c7e4b8458023 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -870,6 +870,9 @@ static int __fragmentation_index(unsigned int order, struct contig_page_info *in
 {
 	unsigned long requested = 1UL << order;
 
+	if (WARN_ON_ONCE(order >= MAX_ORDER))
+		return 0;
+
 	if (!info->free_blocks_total)
 		return 0;
 
@@ -1071,6 +1074,8 @@ const char * const vmstat_text[] = {
 #endif
 	"thp_zero_page_alloc",
 	"thp_zero_page_alloc_failed",
+	"thp_swpout",
+	"thp_swpout_fallback",
 #endif
 #ifdef CONFIG_MEMORY_BALLOON
 	"balloon_inflate",
@@ -1093,6 +1098,10 @@ const char * const vmstat_text[] = {
 	"vmacache_find_hits",
 	"vmacache_full_flushes",
 #endif
+#ifdef CONFIG_SWAP
+	"swap_ra",
+	"swap_ra_hit",
+#endif
 #endif /* CONFIG_VM_EVENTS_COUNTERS */
 };
 #endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA */
@@ -1250,7 +1259,7 @@ static void pagetypeinfo_showblockcount_print(struct seq_file *m,
 	seq_putc(m, '\n');
 }
 
-/* Print out the free pages at each order for each migratetype */
+/* Print out the number of pageblocks for each migratetype */
 static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
 {
 	int mtype;
@@ -1500,7 +1509,7 @@ static void *vmstat_start(struct seq_file *m, loff_t *pos)
 	if (!v)
 		return ERR_PTR(-ENOMEM);
 	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
-		v[i] = global_page_state(i);
+		v[i] = global_zone_page_state(i);
 	v += NR_VM_ZONE_STAT_ITEMS;
 
 	for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
@@ -1589,7 +1598,7 @@ int vmstat_refresh(struct ctl_table *table, int write,
 	 * which can equally be echo'ed to or cat'ted from (by root),
 	 * can be used to update the stats just before reading them.
 	 *
-	 * Oh, and since global_page_state() etc. are so careful to hide
+	 * Oh, and since global_zone_page_state() etc. are so careful to hide
 	 * transiently negative values, report an error here if any of
 	 * the stats is negative, so we know to go looking for imbalance.
 	 */
diff --git a/mm/z3fold.c b/mm/z3fold.c
index 54f63c4a809a..486550df32be 100644
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -23,10 +23,13 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/atomic.h>
+#include <linux/sched.h>
 #include <linux/list.h>
 #include <linux/mm.h>
 #include <linux/module.h>
+#include <linux/percpu.h>
 #include <linux/preempt.h>
+#include <linux/workqueue.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/zpool.h>
@@ -48,11 +51,15 @@ enum buddy {
 };
 
 /*
- * struct z3fold_header - z3fold page metadata occupying the first chunk of each
+ * struct z3fold_header - z3fold page metadata occupying first chunks of each
  *			z3fold page, except for HEADLESS pages
- * @buddy:	links the z3fold page into the relevant list in the pool
+ * @buddy:		links the z3fold page into the relevant list in the
+ *			pool
  * @page_lock:		per-page lock
- * @refcount:		reference cound for the z3fold page
+ * @refcount:		reference count for the z3fold page
+ * @work:		work_struct for page layout optimization
+ * @pool:		pointer to the pool which this page belongs to
+ * @cpu:		CPU which this page "belongs" to
  * @first_chunks:	the size of the first buddy in chunks, 0 if free
  * @middle_chunks:	the size of the middle buddy in chunks, 0 if free
  * @last_chunks:	the size of the last buddy in chunks, 0 if free
@@ -62,6 +69,9 @@ struct z3fold_header {
 	struct list_head buddy;
 	spinlock_t page_lock;
 	struct kref refcount;
+	struct work_struct work;
+	struct z3fold_pool *pool;
+	short cpu;
 	unsigned short first_chunks;
 	unsigned short middle_chunks;
 	unsigned short last_chunks;
@@ -92,28 +102,39 @@ struct z3fold_header {
 
 /**
  * struct z3fold_pool - stores metadata for each z3fold pool
- * @lock:	protects all pool fields and first|last_chunk fields of any
- *		z3fold page in the pool
- * @unbuddied:	array of lists tracking z3fold pages that contain 2- buddies;
- *		the lists each z3fold page is added to depends on the size of
- *		its free region.
+ * @name:	pool name
+ * @lock:	protects pool unbuddied/lru lists
+ * @stale_lock:	protects pool stale page list
+ * @unbuddied:	per-cpu array of lists tracking z3fold pages that contain 2-
+ *		buddies; the list each z3fold page is added to depends on
+ *		the size of its free region.
  * @lru:	list tracking the z3fold pages in LRU order by most recently
  *		added buddy.
+ * @stale:	list of pages marked for freeing
  * @pages_nr:	number of z3fold pages in the pool.
  * @ops:	pointer to a structure of user defined operations specified at
  *		pool creation time.
+ * @compact_wq:	workqueue for page layout background optimization
+ * @release_wq:	workqueue for safe page release
+ * @work:	work_struct for safe page release
  *
  * This structure is allocated at pool creation time and maintains metadata
  * pertaining to a particular z3fold pool.
  */
 struct z3fold_pool {
+	const char *name;
 	spinlock_t lock;
-	struct list_head unbuddied[NCHUNKS];
+	spinlock_t stale_lock;
+	struct list_head *unbuddied;
 	struct list_head lru;
+	struct list_head stale;
 	atomic64_t pages_nr;
 	const struct z3fold_ops *ops;
 	struct zpool *zpool;
 	const struct zpool_ops *zpool_ops;
+	struct workqueue_struct *compact_wq;
+	struct workqueue_struct *release_wq;
+	struct work_struct work;
 };
 
 /*
@@ -122,9 +143,10 @@ struct z3fold_pool {
 enum z3fold_page_flags {
 	PAGE_HEADLESS = 0,
 	MIDDLE_CHUNK_MAPPED,
+	NEEDS_COMPACTING,
+	PAGE_STALE
 };
 
-
 /*****************
  * Helpers
 *****************/
@@ -138,14 +160,19 @@ static int size_to_chunks(size_t size)
 #define for_each_unbuddied_list(_iter, _begin) \
 	for ((_iter) = (_begin); (_iter) < NCHUNKS; (_iter)++)
 
+static void compact_page_work(struct work_struct *w);
+
 /* Initializes the z3fold header of a newly allocated z3fold page */
-static struct z3fold_header *init_z3fold_page(struct page *page)
+static struct z3fold_header *init_z3fold_page(struct page *page,
+					struct z3fold_pool *pool)
 {
 	struct z3fold_header *zhdr = page_address(page);
 
 	INIT_LIST_HEAD(&page->lru);
 	clear_bit(PAGE_HEADLESS, &page->private);
 	clear_bit(MIDDLE_CHUNK_MAPPED, &page->private);
+	clear_bit(NEEDS_COMPACTING, &page->private);
+	clear_bit(PAGE_STALE, &page->private);
 
 	spin_lock_init(&zhdr->page_lock);
 	kref_init(&zhdr->refcount);
@@ -154,7 +181,10 @@ static struct z3fold_header *init_z3fold_page(struct page *page)
 	zhdr->last_chunks = 0;
 	zhdr->first_num = 0;
 	zhdr->start_middle = 0;
+	zhdr->cpu = -1;
+	zhdr->pool = pool;
 	INIT_LIST_HEAD(&zhdr->buddy);
+	INIT_WORK(&zhdr->work, compact_page_work);
 	return zhdr;
 }
 
@@ -164,21 +194,6 @@ static void free_z3fold_page(struct page *page)
 	__free_page(page);
 }
 
-static void release_z3fold_page(struct kref *ref)
-{
-	struct z3fold_header *zhdr;
-	struct page *page;
-
-	zhdr = container_of(ref, struct z3fold_header, refcount);
-	page = virt_to_page(zhdr);
-
-	if (!list_empty(&zhdr->buddy))
-		list_del(&zhdr->buddy);
-	if (!list_empty(&page->lru))
-		list_del(&page->lru);
-	free_z3fold_page(page);
-}
-
 /* Lock a z3fold page */
 static inline void z3fold_page_lock(struct z3fold_header *zhdr)
 {
@@ -228,6 +243,76 @@ static enum buddy handle_to_buddy(unsigned long handle)
 	return (handle - zhdr->first_num) & BUDDY_MASK;
 }
 
+static void __release_z3fold_page(struct z3fold_header *zhdr, bool locked)
+{
+	struct page *page = virt_to_page(zhdr);
+	struct z3fold_pool *pool = zhdr->pool;
+
+	WARN_ON(!list_empty(&zhdr->buddy));
+	set_bit(PAGE_STALE, &page->private);
+	spin_lock(&pool->lock);
+	if (!list_empty(&page->lru))
+		list_del(&page->lru);
+	spin_unlock(&pool->lock);
+	if (locked)
+		z3fold_page_unlock(zhdr);
+	spin_lock(&pool->stale_lock);
+	list_add(&zhdr->buddy, &pool->stale);
+	queue_work(pool->release_wq, &pool->work);
+	spin_unlock(&pool->stale_lock);
+}
+
+static void __attribute__((__unused__))
+			release_z3fold_page(struct kref *ref)
+{
+	struct z3fold_header *zhdr = container_of(ref, struct z3fold_header,
+						refcount);
+	__release_z3fold_page(zhdr, false);
+}
+
+static void release_z3fold_page_locked(struct kref *ref)
+{
+	struct z3fold_header *zhdr = container_of(ref, struct z3fold_header,
+						refcount);
+	WARN_ON(z3fold_page_trylock(zhdr));
+	__release_z3fold_page(zhdr, true);
+}
+
+static void release_z3fold_page_locked_list(struct kref *ref)
+{
+	struct z3fold_header *zhdr = container_of(ref, struct z3fold_header,
+					       refcount);
+	spin_lock(&zhdr->pool->lock);
+	list_del_init(&zhdr->buddy);
+	spin_unlock(&zhdr->pool->lock);
+
+	WARN_ON(z3fold_page_trylock(zhdr));
+	__release_z3fold_page(zhdr, true);
+}
+
+static void free_pages_work(struct work_struct *w)
+{
+	struct z3fold_pool *pool = container_of(w, struct z3fold_pool, work);
+
+	spin_lock(&pool->stale_lock);
+	while (!list_empty(&pool->stale)) {
+		struct z3fold_header *zhdr = list_first_entry(&pool->stale,
+						struct z3fold_header, buddy);
+		struct page *page = virt_to_page(zhdr);
+
+		list_del(&zhdr->buddy);
+		if (WARN_ON(!test_bit(PAGE_STALE, &page->private)))
+			continue;
+		clear_bit(NEEDS_COMPACTING, &page->private);
+		spin_unlock(&pool->stale_lock);
+		cancel_work_sync(&zhdr->work);
+		free_z3fold_page(page);
+		cond_resched();
+		spin_lock(&pool->stale_lock);
+	}
+	spin_unlock(&pool->stale_lock);
+}
+
 /*
  * Returns the number of free chunks in a z3fold page.
  * NB: can't be used with HEADLESS pages.
@@ -252,46 +337,6 @@ static int num_free_chunks(struct z3fold_header *zhdr)
 	return nfree;
 }
 
-/*****************
- * API Functions
-*****************/
-/**
- * z3fold_create_pool() - create a new z3fold pool
- * @gfp:	gfp flags when allocating the z3fold pool structure
- * @ops:	user-defined operations for the z3fold pool
- *
- * Return: pointer to the new z3fold pool or NULL if the metadata allocation
- * failed.
- */
-static struct z3fold_pool *z3fold_create_pool(gfp_t gfp,
-		const struct z3fold_ops *ops)
-{
-	struct z3fold_pool *pool;
-	int i;
-
-	pool = kzalloc(sizeof(struct z3fold_pool), gfp);
-	if (!pool)
-		return NULL;
-	spin_lock_init(&pool->lock);
-	for_each_unbuddied_list(i, 0)
-		INIT_LIST_HEAD(&pool->unbuddied[i]);
-	INIT_LIST_HEAD(&pool->lru);
-	atomic64_set(&pool->pages_nr, 0);
-	pool->ops = ops;
-	return pool;
-}
-
-/**
- * z3fold_destroy_pool() - destroys an existing z3fold pool
- * @pool:	the z3fold pool to be destroyed
- *
- * The pool should be emptied before this function is called.
- */
-static void z3fold_destroy_pool(struct z3fold_pool *pool)
-{
-	kfree(pool);
-}
-
 static inline void *mchunk_memmove(struct z3fold_header *zhdr,
 				unsigned short dst_chunk)
 {
@@ -347,6 +392,117 @@ static int z3fold_compact_page(struct z3fold_header *zhdr)
 	return 0;
 }
 
+static void do_compact_page(struct z3fold_header *zhdr, bool locked)
+{
+	struct z3fold_pool *pool = zhdr->pool;
+	struct page *page;
+	struct list_head *unbuddied;
+	int fchunks;
+
+	page = virt_to_page(zhdr);
+	if (locked)
+		WARN_ON(z3fold_page_trylock(zhdr));
+	else
+		z3fold_page_lock(zhdr);
+	if (test_bit(PAGE_STALE, &page->private) ||
+	    !test_and_clear_bit(NEEDS_COMPACTING, &page->private)) {
+		z3fold_page_unlock(zhdr);
+		return;
+	}
+	spin_lock(&pool->lock);
+	list_del_init(&zhdr->buddy);
+	spin_unlock(&pool->lock);
+
+	z3fold_compact_page(zhdr);
+	unbuddied = get_cpu_ptr(pool->unbuddied);
+	fchunks = num_free_chunks(zhdr);
+	if (fchunks < NCHUNKS &&
+	    (!zhdr->first_chunks || !zhdr->middle_chunks ||
+			!zhdr->last_chunks)) {
+		/* the page's not completely free and it's unbuddied */
+		spin_lock(&pool->lock);
+		list_add(&zhdr->buddy, &unbuddied[fchunks]);
+		spin_unlock(&pool->lock);
+		zhdr->cpu = smp_processor_id();
+	}
+	put_cpu_ptr(pool->unbuddied);
+	z3fold_page_unlock(zhdr);
+}
+
+static void compact_page_work(struct work_struct *w)
+{
+	struct z3fold_header *zhdr = container_of(w, struct z3fold_header,
+						work);
+
+	do_compact_page(zhdr, false);
+}
+
+
+/*
+ * API Functions
+ */
+
+/**
+ * z3fold_create_pool() - create a new z3fold pool
+ * @name:	pool name
+ * @gfp:	gfp flags when allocating the z3fold pool structure
+ * @ops:	user-defined operations for the z3fold pool
+ *
+ * Return: pointer to the new z3fold pool or NULL if the metadata allocation
+ * failed.
+ */
+static struct z3fold_pool *z3fold_create_pool(const char *name, gfp_t gfp,
+		const struct z3fold_ops *ops)
+{
+	struct z3fold_pool *pool = NULL;
+	int i, cpu;
+
+	pool = kzalloc(sizeof(struct z3fold_pool), gfp);
+	if (!pool)
+		goto out;
+	spin_lock_init(&pool->lock);
+	spin_lock_init(&pool->stale_lock);
+	pool->unbuddied = __alloc_percpu(sizeof(struct list_head)*NCHUNKS, 2);
+	for_each_possible_cpu(cpu) {
+		struct list_head *unbuddied =
+				per_cpu_ptr(pool->unbuddied, cpu);
+		for_each_unbuddied_list(i, 0)
+			INIT_LIST_HEAD(&unbuddied[i]);
+	}
+	INIT_LIST_HEAD(&pool->lru);
+	INIT_LIST_HEAD(&pool->stale);
+	atomic64_set(&pool->pages_nr, 0);
+	pool->name = name;
+	pool->compact_wq = create_singlethread_workqueue(pool->name);
+	if (!pool->compact_wq)
+		goto out;
+	pool->release_wq = create_singlethread_workqueue(pool->name);
+	if (!pool->release_wq)
+		goto out_wq;
+	INIT_WORK(&pool->work, free_pages_work);
+	pool->ops = ops;
+	return pool;
+
+out_wq:
+	destroy_workqueue(pool->compact_wq);
+out:
+	kfree(pool);
+	return NULL;
+}
+
+/**
+ * z3fold_destroy_pool() - destroys an existing z3fold pool
+ * @pool:	the z3fold pool to be destroyed
+ *
+ * The pool should be emptied before this function is called.
+ */
+static void z3fold_destroy_pool(struct z3fold_pool *pool)
+{
+	destroy_workqueue(pool->release_wq);
+	destroy_workqueue(pool->compact_wq);
+	kfree(pool);
+}
+
 /**
  * z3fold_alloc() - allocates a region of a given size
  * @pool:	z3fold pool from which to allocate
@@ -371,8 +527,9 @@ static int z3fold_alloc(struct z3fold_pool *pool, size_t size, gfp_t gfp,
 {
 	int chunks = 0, i, freechunks;
 	struct z3fold_header *zhdr = NULL;
+	struct page *page = NULL;
 	enum buddy bud;
-	struct page *page;
+	bool can_sleep = (gfp & __GFP_RECLAIM) == __GFP_RECLAIM;
 
 	if (!size || (gfp & __GFP_HIGHMEM))
 		return -EINVAL;
@@ -383,23 +540,57 @@ static int z3fold_alloc(struct z3fold_pool *pool, size_t size, gfp_t gfp,
 	if (size > PAGE_SIZE - ZHDR_SIZE_ALIGNED - CHUNK_SIZE)
 		bud = HEADLESS;
 	else {
+		struct list_head *unbuddied;
 		chunks = size_to_chunks(size);
 
+lookup:
 		/* First, try to find an unbuddied z3fold page. */
-		zhdr = NULL;
+		unbuddied = get_cpu_ptr(pool->unbuddied);
 		for_each_unbuddied_list(i, chunks) {
-			spin_lock(&pool->lock);
-			zhdr = list_first_entry_or_null(&pool->unbuddied[i],
+			struct list_head *l = &unbuddied[i];
+
+			zhdr = list_first_entry_or_null(READ_ONCE(l),
 						struct z3fold_header, buddy);
-			if (!zhdr || !z3fold_page_trylock(zhdr)) {
-				spin_unlock(&pool->lock);
+
+			if (!zhdr)
 				continue;
+
+			/* Re-check under lock. */
+			spin_lock(&pool->lock);
+			l = &unbuddied[i];
+			if (unlikely(zhdr != list_first_entry(READ_ONCE(l),
+					struct z3fold_header, buddy)) ||
+			    !z3fold_page_trylock(zhdr)) {
+				spin_unlock(&pool->lock);
+				put_cpu_ptr(pool->unbuddied);
+				goto lookup;
 			}
-			kref_get(&zhdr->refcount);
 			list_del_init(&zhdr->buddy);
+			zhdr->cpu = -1;
 			spin_unlock(&pool->lock);
 
 			page = virt_to_page(zhdr);
+			if (test_bit(NEEDS_COMPACTING, &page->private)) {
+				z3fold_page_unlock(zhdr);
+				zhdr = NULL;
+				put_cpu_ptr(pool->unbuddied);
+				if (can_sleep)
+					cond_resched();
+				goto lookup;
+			}
+
+			/*
+			 * this page could not be removed from its unbuddied
+			 * list while pool lock was held, and then we've taken
+			 * page lock so kref_put could not be called before
+			 * we got here, so it's safe to just call kref_get()
+			 */
+			kref_get(&zhdr->refcount);
+			break;
+		}
+		put_cpu_ptr(pool->unbuddied);
+
+		if (zhdr) {
 			if (zhdr->first_chunks == 0) {
 				if (zhdr->middle_chunks != 0 &&
 				    chunks >= zhdr->start_middle)
@@ -411,32 +602,49 @@ static int z3fold_alloc(struct z3fold_pool *pool, size_t size, gfp_t gfp,
 			else if (zhdr->middle_chunks == 0)
 				bud = MIDDLE;
 			else {
-				z3fold_page_unlock(zhdr);
-				spin_lock(&pool->lock);
 				if (kref_put(&zhdr->refcount,
-					     release_z3fold_page))
+					     release_z3fold_page_locked))
 					atomic64_dec(&pool->pages_nr);
-				spin_unlock(&pool->lock);
+				else
+					z3fold_page_unlock(zhdr);
 				pr_err("No free chunks in unbuddied\n");
 				WARN_ON(1);
-				continue;
+				goto lookup;
 			}
 			goto found;
 		}
 		bud = FIRST;
 	}
 
-	/* Couldn't find unbuddied z3fold page, create new one */
-	page = alloc_page(gfp);
+	spin_lock(&pool->stale_lock);
+	zhdr = list_first_entry_or_null(&pool->stale,
+					struct z3fold_header, buddy);
+	/*
+	 * Before allocating a page, let's see if we can take one from the
+	 * stale pages list. cancel_work_sync() can sleep so we must make
+	 * sure it won't be called in case we're in atomic context.
+	 */
+	if (zhdr && (can_sleep || !work_pending(&zhdr->work) ||
+	    !unlikely(work_busy(&zhdr->work)))) {
+		list_del(&zhdr->buddy);
+		clear_bit(NEEDS_COMPACTING, &page->private);
+		spin_unlock(&pool->stale_lock);
+		if (can_sleep)
+			cancel_work_sync(&zhdr->work);
+		page = virt_to_page(zhdr);
+	} else {
+		spin_unlock(&pool->stale_lock);
+		page = alloc_page(gfp);
+	}
+
 	if (!page)
 		return -ENOMEM;
 
 	atomic64_inc(&pool->pages_nr);
-	zhdr = init_z3fold_page(page);
+	zhdr = init_z3fold_page(page, pool);
 
 	if (bud == HEADLESS) {
 		set_bit(PAGE_HEADLESS, &page->private);
-		spin_lock(&pool->lock);
 		goto headless;
 	}
 	z3fold_page_lock(zhdr);
@@ -451,15 +659,21 @@ found:
 		zhdr->start_middle = zhdr->first_chunks + ZHDR_CHUNKS;
 	}
 
-	spin_lock(&pool->lock);
 	if (zhdr->first_chunks == 0 || zhdr->last_chunks == 0 ||
 			zhdr->middle_chunks == 0) {
+		struct list_head *unbuddied = get_cpu_ptr(pool->unbuddied);
+
 		/* Add to unbuddied list */
 		freechunks = num_free_chunks(zhdr);
-		list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);
+		spin_lock(&pool->lock);
+		list_add(&zhdr->buddy, &unbuddied[freechunks]);
+		spin_unlock(&pool->lock);
+		zhdr->cpu = smp_processor_id();
+		put_cpu_ptr(pool->unbuddied);
 	}
 
 headless:
+	spin_lock(&pool->lock);
 	/* Add/move z3fold page to beginning of LRU */
 	if (!list_empty(&page->lru))
 		list_del(&page->lru);
@@ -487,7 +701,6 @@ headless:
 static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 {
 	struct z3fold_header *zhdr;
-	int freechunks;
 	struct page *page;
 	enum buddy bud;
 
@@ -526,25 +739,27 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
 		spin_unlock(&pool->lock);
 		free_z3fold_page(page);
 		atomic64_dec(&pool->pages_nr);
-	} else {
-		if (zhdr->first_chunks != 0 || zhdr->middle_chunks != 0 ||
-		    zhdr->last_chunks != 0) {
-			z3fold_compact_page(zhdr);
-			/* Add to the unbuddied list */
-			spin_lock(&pool->lock);
-			if (!list_empty(&zhdr->buddy))
-				list_del(&zhdr->buddy);
-			freechunks = num_free_chunks(zhdr);
-			list_add(&zhdr->buddy, &pool->unbuddied[freechunks]);
-			spin_unlock(&pool->lock);
-		}
+		return;
+	}
+
+	if (kref_put(&zhdr->refcount, release_z3fold_page_locked_list)) {
+		atomic64_dec(&pool->pages_nr);
+		return;
+	}
+	if (test_and_set_bit(NEEDS_COMPACTING, &page->private)) {
 		z3fold_page_unlock(zhdr);
+		return;
+	}
+	if (zhdr->cpu < 0 || !cpu_online(zhdr->cpu)) {
 		spin_lock(&pool->lock);
-		if (kref_put(&zhdr->refcount, release_z3fold_page))
-			atomic64_dec(&pool->pages_nr);
+		list_del_init(&zhdr->buddy);
 		spin_unlock(&pool->lock);
+		zhdr->cpu = -1;
+		do_compact_page(zhdr, true);
+		return;
 	}
-
+	queue_work_on(zhdr->cpu, pool->compact_wq, &zhdr->work);
+	z3fold_page_unlock(zhdr);
 }
 
 /**
@@ -585,9 +800,10 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
  */
 static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
 {
-	int i, ret = 0, freechunks;
-	struct z3fold_header *zhdr;
-	struct page *page;
+	int i, ret = 0;
+	struct z3fold_header *zhdr = NULL;
+	struct page *page = NULL;
+	struct list_head *pos;
 	unsigned long first_handle = 0, middle_handle = 0, last_handle = 0;
 
 	spin_lock(&pool->lock);
@@ -600,16 +816,24 @@ static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
 			spin_unlock(&pool->lock);
 			return -EINVAL;
 		}
-		page = list_last_entry(&pool->lru, struct page, lru);
+		list_for_each_prev(pos, &pool->lru) {
+			page = list_entry(pos, struct page, lru);
+			if (test_bit(PAGE_HEADLESS, &page->private))
+				/* candidate found */
+				break;
+
+			zhdr = page_address(page);
+			if (!z3fold_page_trylock(zhdr))
+				continue; /* can't evict at this point */
+			kref_get(&zhdr->refcount);
+			list_del_init(&zhdr->buddy);
+			zhdr->cpu = -1;
+		}
+
 		list_del_init(&page->lru);
+		spin_unlock(&pool->lock);
 
-		zhdr = page_address(page);
 		if (!test_bit(PAGE_HEADLESS, &page->private)) {
-			if (!list_empty(&zhdr->buddy))
-				list_del_init(&zhdr->buddy);
-			kref_get(&zhdr->refcount);
-			spin_unlock(&pool->lock);
-			z3fold_page_lock(zhdr);
 			/*
 			 * We need encode the handles before unlocking, since
 			 * we can race with free that will set
@@ -624,11 +848,14 @@ static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
 				middle_handle = encode_handle(zhdr, MIDDLE);
 			if (zhdr->last_chunks)
 				last_handle = encode_handle(zhdr, LAST);
+			/*
+			 * it's safe to unlock here because we hold a
+			 * reference to this page
+			 */
 			z3fold_page_unlock(zhdr);
 		} else {
 			first_handle = encode_handle(zhdr, HEADLESS);
 			last_handle = middle_handle = 0;
-			spin_unlock(&pool->lock);
 		}
 
 		/* Issue the eviction callback(s) */
@@ -652,31 +879,12 @@ next:
 			if (ret == 0) {
 				free_z3fold_page(page);
 				return 0;
-			} else {
-				spin_lock(&pool->lock);
-			}
-		} else {
-			z3fold_page_lock(zhdr);
-			if ((zhdr->first_chunks || zhdr->last_chunks ||
-			     zhdr->middle_chunks) &&
-			    !(zhdr->first_chunks && zhdr->last_chunks &&
-			      zhdr->middle_chunks)) {
-				z3fold_compact_page(zhdr);
-				/* add to unbuddied list */
-				spin_lock(&pool->lock);
-				freechunks = num_free_chunks(zhdr);
-				list_add(&zhdr->buddy,
-					 &pool->unbuddied[freechunks]);
-				spin_unlock(&pool->lock);
-			}
-			z3fold_page_unlock(zhdr);
-			spin_lock(&pool->lock);
-			if (kref_put(&zhdr->refcount, release_z3fold_page)) {
-				spin_unlock(&pool->lock);
-				atomic64_dec(&pool->pages_nr);
-				return 0;
 			}
+		} else if (kref_put(&zhdr->refcount, release_z3fold_page)) {
+			atomic64_dec(&pool->pages_nr);
+			return 0;
 		}
+		spin_lock(&pool->lock);
 
 		/*
 		 * Add to the beginning of LRU.
@@ -795,7 +1003,8 @@ static void *z3fold_zpool_create(const char *name, gfp_t gfp,
 {
 	struct z3fold_pool *pool;
 
-	pool = z3fold_create_pool(gfp, zpool_ops ? &z3fold_zpool_ops : NULL);
+	pool = z3fold_create_pool(name, gfp,
+				zpool_ops ? &z3fold_zpool_ops : NULL);
 	if (pool) {
 		pool->zpool = zpool;
 		pool->zpool_ops = zpool_ops;
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 308acb9d814b..62457eb82330 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -1983,8 +1983,11 @@ int zs_page_migrate(struct address_space *mapping, struct page *newpage,
 
 	spin_lock(&class->lock);
 	if (!get_zspage_inuse(zspage)) {
-		ret = -EBUSY;
-		goto unlock_class;
+		/*
+		 * Set "offset" to end of the page so that every loops
+		 * skips unnecessary object scanning.
+		 */
+		offset = PAGE_SIZE;
 	}
 
 	pos = offset;
@@ -2052,7 +2055,6 @@ unpin_objects:
 		}
 	}
 	kunmap_atomic(s_addr);
-unlock_class:
 	spin_unlock(&class->lock);
 	migrate_write_unlock(zspage);
author	Linus Torvalds <torvalds@linux-foundation.org>	2017-09-07 06:49:49 +0300
committer	Linus Torvalds <torvalds@linux-foundation.org>	2017-09-07 06:49:49 +0300
commit	d34fc1adf01ff87026da85fb972dc259dc347540 (patch)
tree	27356073d423187157b7cdb69da32b53102fb9e7 /mm
parent	1c9fe4409ce3e9c78b1ed96ee8ed699d4f03bf33 (diff)
parent	d2cd9ede6e193dd7d88b6d27399e96229a551b19 (diff)
download	linux-d34fc1adf01ff87026da85fb972dc259dc347540.tar.xz