Merge tag 'v3.5-rc4' into drm-intel-next-queued

I want to merge the "no more fake agp on gen6+" patches into
drm-intel-next (well, the last pieces). But a patch in 3.5-rc4 also
adds a new use of dev->agp. Hence the backmarge to sort this out, for
otherwise drm-intel-next merged into Linus' tree would conflict in the
relevant code, things would compile but nicely OOPS at driver load :(

Conflicts in this merge are just simple cases of "both branches
changed/added lines at the same place". The only tricky part is to
keep the order correct wrt the unwind code in case of errors in
intel_ringbuffer.c (and the MI_DISPLAY_FLIP #defines in i915_reg.h
together, obviously).

Conflicts:
	drivers/gpu/drm/i915/i915_reg.h
	drivers/gpu/drm/i915/intel_ringbuffer.c

Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

27 files changed, 621 insertions, 398 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index b2176374b98e..82fed4eb2b6f 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -389,3 +389,20 @@ config CLEANCACHE
 	  in a negligible performance hit.
 
 	  If unsure, say Y to enable cleancache
+
+config FRONTSWAP
+	bool "Enable frontswap to cache swap pages if tmem is present"
+	depends on SWAP
+	default n
+	help
+	  Frontswap is so named because it can be thought of as the opposite
+	  of a "backing" store for a swap device.  The data is stored into
+	  "transcendent memory", memory that is not directly accessible or
+	  addressable by the kernel and is of unknown and possibly
+	  time-varying size.  When space in transcendent memory is available,
+	  a significant swap I/O reduction may be achieved.  When none is
+	  available, all frontswap calls are reduced to a single pointer-
+	  compare-against-NULL resulting in a negligible performance hit
+	  and swap data is stored as normal on the matching swap device.
+
+	  If unsure, say Y to enable frontswap.
diff --git a/mm/Makefile b/mm/Makefile
index a156285ce88d..2e2fbbefb99f 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_HAVE_MEMBLOCK) += memblock.o
 
 obj-$(CONFIG_BOUNCE)	+= bounce.o
 obj-$(CONFIG_SWAP)	+= page_io.o swap_state.o swapfile.o
+obj-$(CONFIG_FRONTSWAP)	+= frontswap.o
 obj-$(CONFIG_HAS_DMA)	+= dmapool.o
 obj-$(CONFIG_HUGETLBFS)	+= hugetlb.o
 obj-$(CONFIG_NUMA) 	+= mempolicy.o
diff --git a/mm/cleancache.c b/mm/cleancache.c
index 5646c740f613..32e6f4136fa2 100644
--- a/mm/cleancache.c
+++ b/mm/cleancache.c
@@ -80,7 +80,7 @@ EXPORT_SYMBOL(__cleancache_init_shared_fs);
 static int cleancache_get_key(struct inode *inode,
 			      struct cleancache_filekey *key)
 {
-	int (*fhfn)(struct dentry *, __u32 *fh, int *, int);
+	int (*fhfn)(struct inode *, __u32 *fh, int *, struct inode *);
 	int len = 0, maxlen = CLEANCACHE_KEY_MAX;
 	struct super_block *sb = inode->i_sb;
 
@@ -88,9 +88,7 @@ static int cleancache_get_key(struct inode *inode,
 	if (sb->s_export_op != NULL) {
 		fhfn = sb->s_export_op->encode_fh;
 		if  (fhfn) {
-			struct dentry d;
-			d.d_inode = inode;
-			len = (*fhfn)(&d, &key->u.fh[0], &maxlen, 0);
+			len = (*fhfn)(inode, &key->u.fh[0], &maxlen, NULL);
 			if (len <= 0 || len == 255)
 				return -1;
 			if (maxlen > CLEANCACHE_KEY_MAX)
diff --git a/mm/compaction.c b/mm/compaction.c
index 4ac338af5120..7ea259d82a99 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -236,7 +236,7 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
 	 */
 	while (unlikely(too_many_isolated(zone))) {
 		/* async migration should just abort */
-		if (cc->mode != COMPACT_SYNC)
+		if (!cc->sync)
 			return 0;
 
 		congestion_wait(BLK_RW_ASYNC, HZ/10);
@@ -304,8 +304,7 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
 		 * satisfies the allocation
 		 */
 		pageblock_nr = low_pfn >> pageblock_order;
-		if (cc->mode != COMPACT_SYNC &&
-		    last_pageblock_nr != pageblock_nr &&
+		if (!cc->sync && last_pageblock_nr != pageblock_nr &&
 		    !migrate_async_suitable(get_pageblock_migratetype(page))) {
 			low_pfn += pageblock_nr_pages;
 			low_pfn = ALIGN(low_pfn, pageblock_nr_pages) - 1;
@@ -326,7 +325,7 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
 			continue;
 		}
 
-		if (cc->mode != COMPACT_SYNC)
+		if (!cc->sync)
 			mode |= ISOLATE_ASYNC_MIGRATE;
 
 		lruvec = mem_cgroup_page_lruvec(page, zone);
@@ -361,90 +360,27 @@ isolate_migratepages_range(struct zone *zone, struct compact_control *cc,
 
 #endif /* CONFIG_COMPACTION || CONFIG_CMA */
 #ifdef CONFIG_COMPACTION
-/*
- * Returns true if MIGRATE_UNMOVABLE pageblock was successfully
- * converted to MIGRATE_MOVABLE type, false otherwise.
- */
-static bool rescue_unmovable_pageblock(struct page *page)
-{
-	unsigned long pfn, start_pfn, end_pfn;
-	struct page *start_page, *end_page;
-
-	pfn = page_to_pfn(page);
-	start_pfn = pfn & ~(pageblock_nr_pages - 1);
-	end_pfn = start_pfn + pageblock_nr_pages;
-
-	start_page = pfn_to_page(start_pfn);
-	end_page = pfn_to_page(end_pfn);
-
-	/* Do not deal with pageblocks that overlap zones */
-	if (page_zone(start_page) != page_zone(end_page))
-		return false;
-
-	for (page = start_page, pfn = start_pfn; page < end_page; pfn++,
-								  page++) {
-		if (!pfn_valid_within(pfn))
-			continue;
-
-		if (PageBuddy(page)) {
-			int order = page_order(page);
-
-			pfn += (1 << order) - 1;
-			page += (1 << order) - 1;
-
-			continue;
-		} else if (page_count(page) == 0 || PageLRU(page))
-			continue;
-
-		return false;
-	}
-
-	set_pageblock_migratetype(page, MIGRATE_MOVABLE);
-	move_freepages_block(page_zone(page), page, MIGRATE_MOVABLE);
-	return true;
-}
 
-enum smt_result {
-	GOOD_AS_MIGRATION_TARGET,
-	FAIL_UNMOVABLE_TARGET,
-	FAIL_BAD_TARGET,
-};
-
-/*
- * Returns GOOD_AS_MIGRATION_TARGET if the page is within a block
- * suitable for migration to, FAIL_UNMOVABLE_TARGET if the page
- * is within a MIGRATE_UNMOVABLE block, FAIL_BAD_TARGET otherwise.
- */
-static enum smt_result suitable_migration_target(struct page *page,
-				      struct compact_control *cc)
+/* Returns true if the page is within a block suitable for migration to */
+static bool suitable_migration_target(struct page *page)
 {
 
 	int migratetype = get_pageblock_migratetype(page);
 
 	/* Don't interfere with memory hot-remove or the min_free_kbytes blocks */
 	if (migratetype == MIGRATE_ISOLATE || migratetype == MIGRATE_RESERVE)
-		return FAIL_BAD_TARGET;
+		return false;
 
 	/* If the page is a large free page, then allow migration */
 	if (PageBuddy(page) && page_order(page) >= pageblock_order)
-		return GOOD_AS_MIGRATION_TARGET;
+		return true;
 
 	/* If the block is MIGRATE_MOVABLE or MIGRATE_CMA, allow migration */
-	if (cc->mode != COMPACT_ASYNC_UNMOVABLE &&
-	    migrate_async_suitable(migratetype))
-		return GOOD_AS_MIGRATION_TARGET;
-
-	if (cc->mode == COMPACT_ASYNC_MOVABLE &&
-	    migratetype == MIGRATE_UNMOVABLE)
-		return FAIL_UNMOVABLE_TARGET;
-
-	if (cc->mode != COMPACT_ASYNC_MOVABLE &&
-	    migratetype == MIGRATE_UNMOVABLE &&
-	    rescue_unmovable_pageblock(page))
-		return GOOD_AS_MIGRATION_TARGET;
+	if (migrate_async_suitable(migratetype))
+		return true;
 
 	/* Otherwise skip the block */
-	return FAIL_BAD_TARGET;
+	return false;
 }
 
 /*
@@ -478,13 +414,6 @@ static void isolate_freepages(struct zone *zone,
 	zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
 
 	/*
-	 * isolate_freepages() may be called more than once during
-	 * compact_zone_order() run and we want only the most recent
-	 * count.
-	 */
-	cc->nr_pageblocks_skipped = 0;
-
-	/*
 	 * Isolate free pages until enough are available to migrate the
 	 * pages on cc->migratepages. We stop searching if the migrate
 	 * and free page scanners meet or enough free pages are isolated.
@@ -492,7 +421,6 @@ static void isolate_freepages(struct zone *zone,
 	for (; pfn > low_pfn && cc->nr_migratepages > nr_freepages;
 					pfn -= pageblock_nr_pages) {
 		unsigned long isolated;
-		enum smt_result ret;
 
 		if (!pfn_valid(pfn))
 			continue;
@@ -509,12 +437,9 @@ static void isolate_freepages(struct zone *zone,
 			continue;
 
 		/* Check the block is suitable for migration */
-		ret = suitable_migration_target(page, cc);
-		if (ret != GOOD_AS_MIGRATION_TARGET) {
-			if (ret == FAIL_UNMOVABLE_TARGET)
-				cc->nr_pageblocks_skipped++;
+		if (!suitable_migration_target(page))
 			continue;
-		}
+
 		/*
 		 * Found a block suitable for isolating free pages from. Now
 		 * we disabled interrupts, double check things are ok and
@@ -523,14 +448,12 @@ static void isolate_freepages(struct zone *zone,
 		 */
 		isolated = 0;
 		spin_lock_irqsave(&zone->lock, flags);
-		ret = suitable_migration_target(page, cc);
-		if (ret == GOOD_AS_MIGRATION_TARGET) {
+		if (suitable_migration_target(page)) {
 			end_pfn = min(pfn + pageblock_nr_pages, zone_end_pfn);
 			isolated = isolate_freepages_block(pfn, end_pfn,
 							   freelist, false);
 			nr_freepages += isolated;
-		} else if (ret == FAIL_UNMOVABLE_TARGET)
-			cc->nr_pageblocks_skipped++;
+		}
 		spin_unlock_irqrestore(&zone->lock, flags);
 
 		/*
@@ -762,9 +685,8 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
 
 		nr_migrate = cc->nr_migratepages;
 		err = migrate_pages(&cc->migratepages, compaction_alloc,
-			(unsigned long)&cc->freepages, false,
-			(cc->mode == COMPACT_SYNC) ? MIGRATE_SYNC_LIGHT
-						      : MIGRATE_ASYNC);
+				(unsigned long)cc, false,
+				cc->sync ? MIGRATE_SYNC_LIGHT : MIGRATE_ASYNC);
 		update_nr_listpages(cc);
 		nr_remaining = cc->nr_migratepages;
 
@@ -793,8 +715,7 @@ out:
 
 static unsigned long compact_zone_order(struct zone *zone,
 				 int order, gfp_t gfp_mask,
-				 enum compact_mode mode,
-				 unsigned long *nr_pageblocks_skipped)
+				 bool sync)
 {
 	struct compact_control cc = {
 		.nr_freepages = 0,
@@ -802,17 +723,12 @@ static unsigned long compact_zone_order(struct zone *zone,
 		.order = order,
 		.migratetype = allocflags_to_migratetype(gfp_mask),
 		.zone = zone,
-		.mode = mode,
+		.sync = sync,
 	};
-	unsigned long rc;
-
 	INIT_LIST_HEAD(&cc.freepages);
 	INIT_LIST_HEAD(&cc.migratepages);
 
-	rc = compact_zone(zone, &cc);
-	*nr_pageblocks_skipped = cc.nr_pageblocks_skipped;
-
-	return rc;
+	return compact_zone(zone, &cc);
 }
 
 int sysctl_extfrag_threshold = 500;
@@ -837,8 +753,6 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist,
 	struct zoneref *z;
 	struct zone *zone;
 	int rc = COMPACT_SKIPPED;
-	unsigned long nr_pageblocks_skipped;
-	enum compact_mode mode;
 
 	/*
 	 * Check whether it is worth even starting compaction. The order check is
@@ -855,22 +769,12 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist,
 								nodemask) {
 		int status;
 
-		mode = sync ? COMPACT_SYNC : COMPACT_ASYNC_MOVABLE;
-retry:
-		status = compact_zone_order(zone, order, gfp_mask, mode,
-						&nr_pageblocks_skipped);
+		status = compact_zone_order(zone, order, gfp_mask, sync);
 		rc = max(status, rc);
 
 		/* If a normal allocation would succeed, stop compacting */
 		if (zone_watermark_ok(zone, order, low_wmark_pages(zone), 0, 0))
 			break;
-
-		if (rc == COMPACT_COMPLETE && mode == COMPACT_ASYNC_MOVABLE) {
-			if (nr_pageblocks_skipped) {
-				mode = COMPACT_ASYNC_UNMOVABLE;
-				goto retry;
-			}
-		}
 	}
 
 	return rc;
@@ -904,7 +808,7 @@ static int __compact_pgdat(pg_data_t *pgdat, struct compact_control *cc)
 			if (ok && cc->order > zone->compact_order_failed)
 				zone->compact_order_failed = cc->order + 1;
 			/* Currently async compaction is never deferred. */
-			else if (!ok && cc->mode == COMPACT_SYNC)
+			else if (!ok && cc->sync)
 				defer_compaction(zone, cc->order);
 		}
 
@@ -919,7 +823,7 @@ int compact_pgdat(pg_data_t *pgdat, int order)
 {
 	struct compact_control cc = {
 		.order = order,
-		.mode = COMPACT_ASYNC_MOVABLE,
+		.sync = false,
 	};
 
 	return __compact_pgdat(pgdat, &cc);
@@ -929,7 +833,7 @@ static int compact_node(int nid)
 {
 	struct compact_control cc = {
 		.order = -1,
-		.mode = COMPACT_SYNC,
+		.sync = true,
 	};
 
 	return __compact_pgdat(NODE_DATA(nid), &cc);
diff --git a/mm/filemap.c b/mm/filemap.c
index 64b48f934b89..a4a5260b0279 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1899,71 +1899,6 @@ struct page *read_cache_page(struct address_space *mapping,
 }
 EXPORT_SYMBOL(read_cache_page);
 
-/*
- * The logic we want is
- *
- *	if suid or (sgid and xgrp)
- *		remove privs
- */
-int should_remove_suid(struct dentry *dentry)
-{
-	umode_t mode = dentry->d_inode->i_mode;
-	int kill = 0;
-
-	/* suid always must be killed */
-	if (unlikely(mode & S_ISUID))
-		kill = ATTR_KILL_SUID;
-
-	/*
-	 * sgid without any exec bits is just a mandatory locking mark; leave
-	 * it alone.  If some exec bits are set, it's a real sgid; kill it.
-	 */
-	if (unlikely((mode & S_ISGID) && (mode & S_IXGRP)))
-		kill |= ATTR_KILL_SGID;
-
-	if (unlikely(kill && !capable(CAP_FSETID) && S_ISREG(mode)))
-		return kill;
-
-	return 0;
-}
-EXPORT_SYMBOL(should_remove_suid);
-
-static int __remove_suid(struct dentry *dentry, int kill)
-{
-	struct iattr newattrs;
-
-	newattrs.ia_valid = ATTR_FORCE | kill;
-	return notify_change(dentry, &newattrs);
-}
-
-int file_remove_suid(struct file *file)
-{
-	struct dentry *dentry = file->f_path.dentry;
-	struct inode *inode = dentry->d_inode;
-	int killsuid;
-	int killpriv;
-	int error = 0;
-
-	/* Fast path for nothing security related */
-	if (IS_NOSEC(inode))
-		return 0;
-
-	killsuid = should_remove_suid(dentry);
-	killpriv = security_inode_need_killpriv(dentry);
-
-	if (killpriv < 0)
-		return killpriv;
-	if (killpriv)
-		error = security_inode_killpriv(dentry);
-	if (!error && killsuid)
-		error = __remove_suid(dentry, killsuid);
-	if (!error && (inode->i_sb->s_flags & MS_NOSEC))
-		inode->i_flags |= S_NOSEC;
-
-	return error;
-}
-EXPORT_SYMBOL(file_remove_suid);
-
 static size_t __iovec_copy_from_user_inatomic(char *vaddr,
 			const struct iovec *iov, size_t base, size_t bytes)
 {
@@ -2489,7 +2424,9 @@ ssize_t __generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	if (err)
 		goto out;
 
-	file_update_time(file);
+	err = file_update_time(file);
+	if (err)
+		goto out;
 
 	/* coalesce the iovecs and go direct-to-BIO for O_DIRECT */
 	if (unlikely(file->f_flags & O_DIRECT)) {
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index a4eb31132229..213ca1f53409 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -426,7 +426,9 @@ xip_file_write(struct file *filp, const char __user *buf, size_t len,
 	if (ret)
 		goto out_backing;
 
-	file_update_time(filp);
+	ret = file_update_time(filp);
+	if (ret)
+		goto out_backing;
 
 	ret = __xip_file_write (filp, buf, count, pos, ppos);
 
diff --git a/mm/frontswap.c b/mm/frontswap.c
new file mode 100644
index 000000000000..e25025574a02
--- /dev/null
+++ b/mm/frontswap.c
@@ -0,0 +1,314 @@
+/*
+ * Frontswap frontend
+ *
+ * This code provides the generic "frontend" layer to call a matching
+ * "backend" driver implementation of frontswap.  See
+ * Documentation/vm/frontswap.txt for more information.
+ *
+ * Copyright (C) 2009-2012 Oracle Corp.  All rights reserved.
+ * Author: Dan Magenheimer
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
+#include <linux/proc_fs.h>
+#include <linux/security.h>
+#include <linux/capability.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/debugfs.h>
+#include <linux/frontswap.h>
+#include <linux/swapfile.h>
+
+/*
+ * frontswap_ops is set by frontswap_register_ops to contain the pointers
+ * to the frontswap "backend" implementation functions.
+ */
+static struct frontswap_ops frontswap_ops __read_mostly;
+
+/*
+ * This global enablement flag reduces overhead on systems where frontswap_ops
+ * has not been registered, so is preferred to the slower alternative: a
+ * function call that checks a non-global.
+ */
+bool frontswap_enabled __read_mostly;
+EXPORT_SYMBOL(frontswap_enabled);
+
+/*
+ * If enabled, frontswap_store will return failure even on success.  As
+ * a result, the swap subsystem will always write the page to swap, in
+ * effect converting frontswap into a writethrough cache.  In this mode,
+ * there is no direct reduction in swap writes, but a frontswap backend
+ * can unilaterally "reclaim" any pages in use with no data loss, thus
+ * providing increases control over maximum memory usage due to frontswap.
+ */
+static bool frontswap_writethrough_enabled __read_mostly;
+
+#ifdef CONFIG_DEBUG_FS
+/*
+ * Counters available via /sys/kernel/debug/frontswap (if debugfs is
+ * properly configured).  These are for information only so are not protected
+ * against increment races.
+ */
+static u64 frontswap_loads;
+static u64 frontswap_succ_stores;
+static u64 frontswap_failed_stores;
+static u64 frontswap_invalidates;
+
+static inline void inc_frontswap_loads(void) {
+	frontswap_loads++;
+}
+static inline void inc_frontswap_succ_stores(void) {
+	frontswap_succ_stores++;
+}
+static inline void inc_frontswap_failed_stores(void) {
+	frontswap_failed_stores++;
+}
+static inline void inc_frontswap_invalidates(void) {
+	frontswap_invalidates++;
+}
+#else
+static inline void inc_frontswap_loads(void) { }
+static inline void inc_frontswap_succ_stores(void) { }
+static inline void inc_frontswap_failed_stores(void) { }
+static inline void inc_frontswap_invalidates(void) { }
+#endif
+/*
+ * Register operations for frontswap, returning previous thus allowing
+ * detection of multiple backends and possible nesting.
+ */
+struct frontswap_ops frontswap_register_ops(struct frontswap_ops *ops)
+{
+	struct frontswap_ops old = frontswap_ops;
+
+	frontswap_ops = *ops;
+	frontswap_enabled = true;
+	return old;
+}
+EXPORT_SYMBOL(frontswap_register_ops);
+
+/*
+ * Enable/disable frontswap writethrough (see above).
+ */
+void frontswap_writethrough(bool enable)
+{
+	frontswap_writethrough_enabled = enable;
+}
+EXPORT_SYMBOL(frontswap_writethrough);
+
+/*
+ * Called when a swap device is swapon'd.
+ */
+void __frontswap_init(unsigned type)
+{
+	struct swap_info_struct *sis = swap_info[type];
+
+	BUG_ON(sis == NULL);
+	if (sis->frontswap_map == NULL)
+		return;
+	if (frontswap_enabled)
+		(*frontswap_ops.init)(type);
+}
+EXPORT_SYMBOL(__frontswap_init);
+
+/*
+ * "Store" data from a page to frontswap and associate it with the page's
+ * swaptype and offset.  Page must be locked and in the swap cache.
+ * If frontswap already contains a page with matching swaptype and
+ * offset, the frontswap implmentation may either overwrite the data and
+ * return success or invalidate the page from frontswap and return failure.
+ */
+int __frontswap_store(struct page *page)
+{
+	int ret = -1, dup = 0;
+	swp_entry_t entry = { .val = page_private(page), };
+	int type = swp_type(entry);
+	struct swap_info_struct *sis = swap_info[type];
+	pgoff_t offset = swp_offset(entry);
+
+	BUG_ON(!PageLocked(page));
+	BUG_ON(sis == NULL);
+	if (frontswap_test(sis, offset))
+		dup = 1;
+	ret = (*frontswap_ops.store)(type, offset, page);
+	if (ret == 0) {
+		frontswap_set(sis, offset);
+		inc_frontswap_succ_stores();
+		if (!dup)
+			atomic_inc(&sis->frontswap_pages);
+	} else if (dup) {
+		/*
+		  failed dup always results in automatic invalidate of
+		  the (older) page from frontswap
+		 */
+		frontswap_clear(sis, offset);
+		atomic_dec(&sis->frontswap_pages);
+		inc_frontswap_failed_stores();
+	} else
+		inc_frontswap_failed_stores();
+	if (frontswap_writethrough_enabled)
+		/* report failure so swap also writes to swap device */
+		ret = -1;
+	return ret;
+}
+EXPORT_SYMBOL(__frontswap_store);
+
+/*
+ * "Get" data from frontswap associated with swaptype and offset that were
+ * specified when the data was put to frontswap and use it to fill the
+ * specified page with data. Page must be locked and in the swap cache.
+ */
+int __frontswap_load(struct page *page)
+{
+	int ret = -1;
+	swp_entry_t entry = { .val = page_private(page), };
+	int type = swp_type(entry);
+	struct swap_info_struct *sis = swap_info[type];
+	pgoff_t offset = swp_offset(entry);
+
+	BUG_ON(!PageLocked(page));
+	BUG_ON(sis == NULL);
+	if (frontswap_test(sis, offset))
+		ret = (*frontswap_ops.load)(type, offset, page);
+	if (ret == 0)
+		inc_frontswap_loads();
+	return ret;
+}
+EXPORT_SYMBOL(__frontswap_load);
+
+/*
+ * Invalidate any data from frontswap associated with the specified swaptype
+ * and offset so that a subsequent "get" will fail.
+ */
+void __frontswap_invalidate_page(unsigned type, pgoff_t offset)
+{
+	struct swap_info_struct *sis = swap_info[type];
+
+	BUG_ON(sis == NULL);
+	if (frontswap_test(sis, offset)) {
+		(*frontswap_ops.invalidate_page)(type, offset);
+		atomic_dec(&sis->frontswap_pages);
+		frontswap_clear(sis, offset);
+		inc_frontswap_invalidates();
+	}
+}
+EXPORT_SYMBOL(__frontswap_invalidate_page);
+
+/*
+ * Invalidate all data from frontswap associated with all offsets for the
+ * specified swaptype.
+ */
+void __frontswap_invalidate_area(unsigned type)
+{
+	struct swap_info_struct *sis = swap_info[type];
+
+	BUG_ON(sis == NULL);
+	if (sis->frontswap_map == NULL)
+		return;
+	(*frontswap_ops.invalidate_area)(type);
+	atomic_set(&sis->frontswap_pages, 0);
+	memset(sis->frontswap_map, 0, sis->max / sizeof(long));
+}
+EXPORT_SYMBOL(__frontswap_invalidate_area);
+
+/*
+ * Frontswap, like a true swap device, may unnecessarily retain pages
+ * under certain circumstances; "shrink" frontswap is essentially a
+ * "partial swapoff" and works by calling try_to_unuse to attempt to
+ * unuse enough frontswap pages to attempt to -- subject to memory
+ * constraints -- reduce the number of pages in frontswap to the
+ * number given in the parameter target_pages.
+ */
+void frontswap_shrink(unsigned long target_pages)
+{
+	struct swap_info_struct *si = NULL;
+	int si_frontswap_pages;
+	unsigned long total_pages = 0, total_pages_to_unuse;
+	unsigned long pages = 0, pages_to_unuse = 0;
+	int type;
+	bool locked = false;
+
+	/*
+	 * we don't want to hold swap_lock while doing a very
+	 * lengthy try_to_unuse, but swap_list may change
+	 * so restart scan from swap_list.head each time
+	 */
+	spin_lock(&swap_lock);
+	locked = true;
+	total_pages = 0;
+	for (type = swap_list.head; type >= 0; type = si->next) {
+		si = swap_info[type];
+		total_pages += atomic_read(&si->frontswap_pages);
+	}
+	if (total_pages <= target_pages)
+		goto out;
+	total_pages_to_unuse = total_pages - target_pages;
+	for (type = swap_list.head; type >= 0; type = si->next) {
+		si = swap_info[type];
+		si_frontswap_pages = atomic_read(&si->frontswap_pages);
+		if (total_pages_to_unuse < si_frontswap_pages)
+			pages = pages_to_unuse = total_pages_to_unuse;
+		else {
+			pages = si_frontswap_pages;
+			pages_to_unuse = 0; /* unuse all */
+		}
+		/* ensure there is enough RAM to fetch pages from frontswap */
+		if (security_vm_enough_memory_mm(current->mm, pages))
+			continue;
+		vm_unacct_memory(pages);
+		break;
+	}
+	if (type < 0)
+		goto out;
+	locked = false;
+	spin_unlock(&swap_lock);
+	try_to_unuse(type, true, pages_to_unuse);
+out:
+	if (locked)
+		spin_unlock(&swap_lock);
+	return;
+}
+EXPORT_SYMBOL(frontswap_shrink);
+
+/*
+ * Count and return the number of frontswap pages across all
+ * swap devices.  This is exported so that backend drivers can
+ * determine current usage without reading debugfs.
+ */
+unsigned long frontswap_curr_pages(void)
+{
+	int type;
+	unsigned long totalpages = 0;
+	struct swap_info_struct *si = NULL;
+
+	spin_lock(&swap_lock);
+	for (type = swap_list.head; type >= 0; type = si->next) {
+		si = swap_info[type];
+		totalpages += atomic_read(&si->frontswap_pages);
+	}
+	spin_unlock(&swap_lock);
+	return totalpages;
+}
+EXPORT_SYMBOL(frontswap_curr_pages);
+
+static int __init init_frontswap(void)
+{
+#ifdef CONFIG_DEBUG_FS
+	struct dentry *root = debugfs_create_dir("frontswap", NULL);
+	if (root == NULL)
+		return -ENXIO;
+	debugfs_create_u64("loads", S_IRUGO, root, &frontswap_loads);
+	debugfs_create_u64("succ_stores", S_IRUGO, root, &frontswap_succ_stores);
+	debugfs_create_u64("failed_stores", S_IRUGO, root,
+				&frontswap_failed_stores);
+	debugfs_create_u64("invalidates", S_IRUGO,
+				root, &frontswap_invalidates);
+#endif
+	return 0;
+}
+
+module_init(init_frontswap);
diff --git a/mm/internal.h b/mm/internal.h
index 4194ab9dc19b..2ba87fbfb75b 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -94,9 +94,6 @@ extern void putback_lru_page(struct page *page);
 /*
  * in mm/page_alloc.c
  */
-extern void set_pageblock_migratetype(struct page *page, int migratetype);
-extern int move_freepages_block(struct zone *zone, struct page *page,
-				int migratetype);
 extern void __free_pages_bootmem(struct page *page, unsigned int order);
 extern void prep_compound_page(struct page *page, unsigned long order);
 #ifdef CONFIG_MEMORY_FAILURE
@@ -104,7 +101,6 @@ extern bool is_free_buddy_page(struct page *page);
 #endif
 
 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
-#include <linux/compaction.h>
 
 /*
  * in mm/compaction.c
@@ -123,14 +119,11 @@ struct compact_control {
 	unsigned long nr_migratepages;	/* Number of pages to migrate */
 	unsigned long free_pfn;		/* isolate_freepages search base */
 	unsigned long migrate_pfn;	/* isolate_migratepages search base */
-	enum compact_mode mode;		/* Compaction mode */
+	bool sync;			/* Synchronous migration */
 
 	int order;			/* order a direct compactor needs */
 	int migratetype;		/* MOVABLE, RECLAIMABLE etc */
 	struct zone *zone;
-
-	/* Number of UNMOVABLE destination pageblocks skipped during scan */
-	unsigned long nr_pageblocks_skipped;
 };
 
 unsigned long
@@ -350,3 +343,7 @@ extern u64 hwpoison_filter_flags_mask;
 extern u64 hwpoison_filter_flags_value;
 extern u64 hwpoison_filter_memcg;
 extern u32 hwpoison_filter_enable;
+
+extern unsigned long vm_mmap_pgoff(struct file *, unsigned long,
+        unsigned long, unsigned long,
+        unsigned long, unsigned long);
diff --git a/mm/memblock.c b/mm/memblock.c
index 952123eba433..d4382095f8bd 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -184,7 +184,24 @@ static void __init_memblock memblock_remove_region(struct memblock_type *type, u
 	}
 }
 
-static int __init_memblock memblock_double_array(struct memblock_type *type)
+/**
+ * memblock_double_array - double the size of the memblock regions array
+ * @type: memblock type of the regions array being doubled
+ * @new_area_start: starting address of memory range to avoid overlap with
+ * @new_area_size: size of memory range to avoid overlap with
+ *
+ * Double the size of the @type regions array. If memblock is being used to
+ * allocate memory for a new reserved regions array and there is a previously
+ * allocated memory range [@new_area_start,@new_area_start+@new_area_size]
+ * waiting to be reserved, ensure the memory used by the new array does
+ * not overlap.
+ *
+ * RETURNS:
+ * 0 on success, -1 on failure.
+ */
+static int __init_memblock memblock_double_array(struct memblock_type *type,
+						phys_addr_t new_area_start,
+						phys_addr_t new_area_size)
 {
 	struct memblock_region *new_array, *old_array;
 	phys_addr_t old_size, new_size, addr;
@@ -222,7 +239,18 @@ static int __init_memblock memblock_double_array(struct memblock_type *type)
 		new_array = kmalloc(new_size, GFP_KERNEL);
 		addr = new_array ? __pa(new_array) : 0;
 	} else {
-		addr = memblock_find_in_range(0, MEMBLOCK_ALLOC_ACCESSIBLE, new_size, sizeof(phys_addr_t));
+		/* only exclude range when trying to double reserved.regions */
+		if (type != &memblock.reserved)
+			new_area_start = new_area_size = 0;
+
+		addr = memblock_find_in_range(new_area_start + new_area_size,
+						memblock.current_limit,
+						new_size, sizeof(phys_addr_t));
+		if (!addr && new_area_size)
+			addr = memblock_find_in_range(0,
+					min(new_area_start, memblock.current_limit),
+					new_size, sizeof(phys_addr_t));
+
 		new_array = addr ? __va(addr) : 0;
 	}
 	if (!addr) {
@@ -399,7 +427,7 @@ repeat:
 	 */
 	if (!insert) {
 		while (type->cnt + nr_new > type->max)
-			if (memblock_double_array(type) < 0)
+			if (memblock_double_array(type, obase, size) < 0)
 				return -ENOMEM;
 		insert = true;
 		goto repeat;
@@ -450,7 +478,7 @@ static int __init_memblock memblock_isolate_range(struct memblock_type *type,
 
 	/* we'll create at most two more regions */
 	while (type->cnt + 2 > type->max)
-		if (memblock_double_array(type) < 0)
+		if (memblock_double_array(type, base, size) < 0)
 			return -ENOMEM;
 
 	for (i = 0; i < type->cnt; i++) {
@@ -540,9 +568,9 @@ int __init_memblock memblock_reserve(phys_addr_t base, phys_addr_t size)
  * __next_free_mem_range - next function for for_each_free_mem_range()
  * @idx: pointer to u64 loop variable
  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
- * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
- * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
- * @p_nid: ptr to int for nid of the range, can be %NULL
+ * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @out_nid: ptr to int for nid of the range, can be %NULL
  *
  * Find the first free area from *@idx which matches @nid, fill the out
  * parameters, and update *@idx for the next iteration.  The lower 32bit of
@@ -616,9 +644,9 @@ void __init_memblock __next_free_mem_range(u64 *idx, int nid,
  * __next_free_mem_range_rev - next function for for_each_free_mem_range_reverse()
  * @idx: pointer to u64 loop variable
  * @nid: nid: node selector, %MAX_NUMNODES for all nodes
- * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
- * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
- * @p_nid: ptr to int for nid of the range, can be %NULL
+ * @out_start: ptr to phys_addr_t for start address of the range, can be %NULL
+ * @out_end: ptr to phys_addr_t for end address of the range, can be %NULL
+ * @out_nid: ptr to int for nid of the range, can be %NULL
  *
  * Reverse of __next_free_mem_range().
  */
@@ -867,6 +895,16 @@ int __init_memblock memblock_is_memory(phys_addr_t addr)
 	return memblock_search(&memblock.memory, addr) != -1;
 }
 
+/**
+ * memblock_is_region_memory - check if a region is a subset of memory
+ * @base: base of region to check
+ * @size: size of region to check
+ *
+ * Check if the region [@base, @base+@size) is a subset of a memory block.
+ *
+ * RETURNS:
+ * 0 if false, non-zero if true
+ */
 int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size)
 {
 	int idx = memblock_search(&memblock.memory, base);
@@ -879,6 +917,16 @@ int __init_memblock memblock_is_region_memory(phys_addr_t base, phys_addr_t size
 		 memblock.memory.regions[idx].size) >= end;
 }
 
+/**
+ * memblock_is_region_reserved - check if a region intersects reserved memory
+ * @base: base of region to check
+ * @size: size of region to check
+ *
+ * Check if the region [@base, @base+@size) intersects a reserved memory block.
+ *
+ * RETURNS:
+ * 0 if false, non-zero if true
+ */
 int __init_memblock memblock_is_region_reserved(phys_addr_t base, phys_addr_t size)
 {
 	memblock_cap_size(base, &size);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ac35bccadb7b..f72b5e52451a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1148,7 +1148,7 @@ bool __mem_cgroup_same_or_subtree(const struct mem_cgroup *root_memcg,
 {
 	if (root_memcg == memcg)
 		return true;
-	if (!root_memcg->use_hierarchy)
+	if (!root_memcg->use_hierarchy || !memcg)
 		return false;
 	return css_is_ancestor(&memcg->css, &root_memcg->css);
 }
@@ -1234,7 +1234,7 @@ int mem_cgroup_inactive_file_is_low(struct lruvec *lruvec)
 
 /**
  * mem_cgroup_margin - calculate chargeable space of a memory cgroup
- * @mem: the memory cgroup
+ * @memcg: the memory cgroup
  *
  * Returns the maximum amount of memory @mem can be charged with, in
  * pages.
@@ -1508,7 +1508,7 @@ static unsigned long mem_cgroup_reclaim(struct mem_cgroup *memcg,
 
 /**
  * test_mem_cgroup_node_reclaimable
- * @mem: the target memcg
+ * @memcg: the target memcg
  * @nid: the node ID to be checked.
  * @noswap : specify true here if the user wants flle only information.
  *
diff --git a/mm/memory.c b/mm/memory.c
index 1b7dc662bf9f..2466d1250231 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1225,7 +1225,15 @@ static inline unsigned long zap_pmd_range(struct mmu_gather *tlb,
 		next = pmd_addr_end(addr, end);
 		if (pmd_trans_huge(*pmd)) {
 			if (next - addr != HPAGE_PMD_SIZE) {
-				VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem));
+#ifdef CONFIG_DEBUG_VM
+				if (!rwsem_is_locked(&tlb->mm->mmap_sem)) {
+					pr_err("%s: mmap_sem is unlocked! addr=0x%lx end=0x%lx vma->vm_start=0x%lx vma->vm_end=0x%lx\n",
+						__func__, addr, end,
+						vma->vm_start,
+						vma->vm_end);
+					BUG();
+				}
+#endif
 				split_huge_page_pmd(vma->vm_mm, pmd);
 			} else if (zap_huge_pmd(tlb, vma, pmd, addr))
 				goto next;
@@ -1366,7 +1374,7 @@ void unmap_vmas(struct mmu_gather *tlb,
 /**
  * zap_page_range - remove user pages in a given range
  * @vma: vm_area_struct holding the applicable pages
- * @address: starting address of pages to zap
+ * @start: starting address of pages to zap
  * @size: number of bytes to zap
  * @details: details of nonlinear truncation or shared cache invalidation
  *
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index f15c1b24ca18..1d771e4200d2 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1177,7 +1177,7 @@ static long do_mbind(unsigned long start, unsigned long len,
 		if (!list_empty(&pagelist)) {
 			nr_failed = migrate_pages(&pagelist, new_vma_page,
 						(unsigned long)vma,
-						false, true);
+						false, MIGRATE_SYNC);
 			if (nr_failed)
 				putback_lru_pages(&pagelist);
 		}
diff --git a/mm/migrate.c b/mm/migrate.c
index ab81d482ae6f..be26d5cbe56b 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -436,7 +436,10 @@ void migrate_page_copy(struct page *newpage, struct page *page)
 		 * is actually a signal that all of the page has become dirty.
 		 * Whereas only part of our page may be dirty.
 		 */
-		__set_page_dirty_nobuffers(newpage);
+		if (PageSwapBacked(page))
+			SetPageDirty(newpage);
+		else
+			__set_page_dirty_nobuffers(newpage);
  	}
 
 	mlock_migrate_page(newpage, page);
diff --git a/mm/mmap.c b/mm/mmap.c
index 4a9c2a391e28..3edfcdfa42d9 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -971,15 +971,13 @@ static inline unsigned long round_hint_to_min(unsigned long hint)
  * The caller must hold down_write(&current->mm->mmap_sem).
  */
 
-static unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
+unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 			unsigned long len, unsigned long prot,
 			unsigned long flags, unsigned long pgoff)
 {
 	struct mm_struct * mm = current->mm;
 	struct inode *inode;
 	vm_flags_t vm_flags;
-	int error;
-	unsigned long reqprot = prot;
 
 	/*
 	 * Does the application expect PROT_READ to imply PROT_EXEC?
@@ -1101,39 +1099,9 @@ static unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 		}
 	}
 
-	error = security_file_mmap(file, reqprot, prot, flags, addr, 0);
-	if (error)
-		return error;
-
 	return mmap_region(file, addr, len, flags, vm_flags, pgoff);
 }
 
-unsigned long do_mmap(struct file *file, unsigned long addr,
-	unsigned long len, unsigned long prot,
-	unsigned long flag, unsigned long offset)
-{
-	if (unlikely(offset + PAGE_ALIGN(len) < offset))
-		return -EINVAL;
-	if (unlikely(offset & ~PAGE_MASK))
-		return -EINVAL;
-	return do_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
-}
-EXPORT_SYMBOL(do_mmap);
-
-unsigned long vm_mmap(struct file *file, unsigned long addr,
-	unsigned long len, unsigned long prot,
-	unsigned long flag, unsigned long offset)
-{
-	unsigned long ret;
-	struct mm_struct *mm = current->mm;
-
-	down_write(&mm->mmap_sem);
-	ret = do_mmap(file, addr, len, prot, flag, offset);
-	up_write(&mm->mmap_sem);
-	return ret;
-}
-EXPORT_SYMBOL(vm_mmap);
-
 SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 		unsigned long, prot, unsigned long, flags,
 		unsigned long, fd, unsigned long, pgoff)
@@ -1165,10 +1133,7 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
+	retval = vm_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 	if (file)
 		fput(file);
 out:
@@ -1629,7 +1594,9 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
 	if (addr & ~PAGE_MASK)
 		return -EINVAL;
 
-	return arch_rebalance_pgtables(addr, len);
+	addr = arch_rebalance_pgtables(addr, len);
+	error = security_mmap_addr(addr);
+	return error ? error : addr;
 }
 
 EXPORT_SYMBOL(get_unmapped_area);
@@ -1819,7 +1786,7 @@ int expand_downwards(struct vm_area_struct *vma,
 		return -ENOMEM;
 
 	address &= PAGE_MASK;
-	error = security_file_mmap(NULL, 0, 0, 0, address, 1);
+	error = security_mmap_addr(address);
 	if (error)
 		return error;
 
@@ -2159,7 +2126,6 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len)
 
 	return 0;
 }
-EXPORT_SYMBOL(do_munmap);
 
 int vm_munmap(unsigned long start, size_t len)
 {
@@ -2207,10 +2173,6 @@ static unsigned long do_brk(unsigned long addr, unsigned long len)
 	if (!len)
 		return addr;
 
-	error = security_file_mmap(NULL, 0, 0, 0, addr, 1);
-	if (error)
-		return error;
-
 	flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
 
 	error = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
@@ -2563,10 +2525,6 @@ int install_special_mapping(struct mm_struct *mm,
 	vma->vm_ops = &special_mapping_vmops;
 	vma->vm_private_data = pages;
 
-	ret = security_file_mmap(NULL, 0, 0, 0, vma->vm_start, 1);
-	if (ret)
-		goto out;
-
 	ret = insert_vm_struct(mm, vma);
 	if (ret)
 		goto out;
diff --git a/mm/mremap.c b/mm/mremap.c
index db8d983b5a7d..21fed202ddad 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -371,10 +371,6 @@ static unsigned long mremap_to(unsigned long addr,
 	if ((addr <= new_addr) && (addr+old_len) > new_addr)
 		goto out;
 
-	ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
-	if (ret)
-		goto out;
-
 	ret = do_munmap(mm, new_addr, new_len);
 	if (ret)
 		goto out;
@@ -432,15 +428,17 @@ static int vma_expandable(struct vm_area_struct *vma, unsigned long delta)
  * MREMAP_FIXED option added 5-Dec-1999 by Benjamin LaHaise
  * This option implies MREMAP_MAYMOVE.
  */
-unsigned long do_mremap(unsigned long addr,
-	unsigned long old_len, unsigned long new_len,
-	unsigned long flags, unsigned long new_addr)
+SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
+		unsigned long, new_len, unsigned long, flags,
+		unsigned long, new_addr)
 {
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma;
 	unsigned long ret = -EINVAL;
 	unsigned long charged = 0;
 
+	down_write(&current->mm->mmap_sem);
+
 	if (flags & ~(MREMAP_FIXED | MREMAP_MAYMOVE))
 		goto out;
 
@@ -530,25 +528,11 @@ unsigned long do_mremap(unsigned long addr,
 			goto out;
 		}
 
-		ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
-		if (ret)
-			goto out;
 		ret = move_vma(vma, addr, old_len, new_len, new_addr);
 	}
 out:
 	if (ret & ~PAGE_MASK)
 		vm_unacct_memory(charged);
-	return ret;
-}
-
-SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
-		unsigned long, new_len, unsigned long, flags,
-		unsigned long, new_addr)
-{
-	unsigned long ret;
-
-	down_write(&current->mm->mmap_sem);
-	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
 	up_write(&current->mm->mmap_sem);
 	return ret;
 }
diff --git a/mm/nommu.c b/mm/nommu.c
index bb8f4f004a82..d4b0c10872de 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -889,7 +889,6 @@ static int validate_mmap_request(struct file *file,
 				 unsigned long *_capabilities)
 {
 	unsigned long capabilities, rlen;
-	unsigned long reqprot = prot;
 	int ret;
 
 	/* do the simple checks first */
@@ -1047,7 +1046,7 @@ static int validate_mmap_request(struct file *file,
 	}
 
 	/* allow the security API to have its say */
-	ret = security_file_mmap(file, reqprot, prot, flags, addr, 0);
+	ret = security_mmap_addr(addr);
 	if (ret < 0)
 		return ret;
 
@@ -1233,7 +1232,7 @@ enomem:
 /*
  * handle mapping creation for uClinux
  */
-static unsigned long do_mmap_pgoff(struct file *file,
+unsigned long do_mmap_pgoff(struct file *file,
 			    unsigned long addr,
 			    unsigned long len,
 			    unsigned long prot,
@@ -1471,32 +1470,6 @@ error_getting_region:
 	return -ENOMEM;
 }
 
-unsigned long do_mmap(struct file *file, unsigned long addr,
-	unsigned long len, unsigned long prot,
-	unsigned long flag, unsigned long offset)
-{
-	if (unlikely(offset + PAGE_ALIGN(len) < offset))
-		return -EINVAL;
-	if (unlikely(offset & ~PAGE_MASK))
-		return -EINVAL;
-	return do_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
-}
-EXPORT_SYMBOL(do_mmap);
-
-unsigned long vm_mmap(struct file *file, unsigned long addr,
-	unsigned long len, unsigned long prot,
-	unsigned long flag, unsigned long offset)
-{
-	unsigned long ret;
-	struct mm_struct *mm = current->mm;
-
-	down_write(&mm->mmap_sem);
-	ret = do_mmap(file, addr, len, prot, flag, offset);
-	up_write(&mm->mmap_sem);
-	return ret;
-}
-EXPORT_SYMBOL(vm_mmap);
-
 SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 		unsigned long, prot, unsigned long, flags,
 		unsigned long, fd, unsigned long, pgoff)
@@ -1513,9 +1486,7 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 
 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
+	retval = vm_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 
 	if (file)
 		fput(file);
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index ed0e19677360..ac300c99baf6 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -183,7 +183,8 @@ static bool oom_unkillable_task(struct task_struct *p,
 unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
 			  const nodemask_t *nodemask, unsigned long totalpages)
 {
-	unsigned long points;
+	long points;
+	long adj;
 
 	if (oom_unkillable_task(p, memcg, nodemask))
 		return 0;
@@ -192,7 +193,8 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
 	if (!p)
 		return 0;
 
-	if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) {
+	adj = p->signal->oom_score_adj;
+	if (adj == OOM_SCORE_ADJ_MIN) {
 		task_unlock(p);
 		return 0;
 	}
@@ -210,20 +212,17 @@ unsigned long oom_badness(struct task_struct *p, struct mem_cgroup *memcg,
 	 * implementation used by LSMs.
 	 */
 	if (has_capability_noaudit(p, CAP_SYS_ADMIN))
-		points -= 30 * totalpages / 1000;
+		adj -= 30;
 
-	/*
-	 * /proc/pid/oom_score_adj ranges from -1000 to +1000 such that it may
-	 * either completely disable oom killing or always prefer a certain
-	 * task.
-	 */
-	points += p->signal->oom_score_adj * totalpages / 1000;
+	/* Normalize to oom_score_adj units */
+	adj *= totalpages / 1000;
+	points += adj;
 
 	/*
 	 * Never return 0 for an eligible task regardless of the root bonus and
 	 * oom_score_adj (oom_score_adj can't be OOM_SCORE_ADJ_MIN here).
 	 */
-	return points ? points : 1;
+	return points > 0 ? points : 1;
 }
 
 /*
@@ -366,7 +365,7 @@ static struct task_struct *select_bad_process(unsigned int *ppoints,
 
 /**
  * dump_tasks - dump current memory state of all system tasks
- * @mem: current's memory controller, if constrained
+ * @memcg: current's memory controller, if constrained
  * @nodemask: nodemask passed to page allocator for mempolicy ooms
  *
  * Dumps the current memory state of all eligible tasks.  Tasks not in the same
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6092f331b32e..44030096da63 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -219,7 +219,7 @@ EXPORT_SYMBOL(nr_online_nodes);
 
 int page_group_by_mobility_disabled __read_mostly;
 
-void set_pageblock_migratetype(struct page *page, int migratetype)
+static void set_pageblock_migratetype(struct page *page, int migratetype)
 {
 
 	if (unlikely(page_group_by_mobility_disabled))
@@ -954,8 +954,8 @@ static int move_freepages(struct zone *zone,
 	return pages_moved;
 }
 
-int move_freepages_block(struct zone *zone, struct page *page,
-			 int migratetype)
+static int move_freepages_block(struct zone *zone, struct page *page,
+				int migratetype)
 {
 	unsigned long start_pfn, end_pfn;
 	struct page *start_page, *end_page;
@@ -5651,7 +5651,7 @@ static int __alloc_contig_migrate_range(unsigned long start, unsigned long end)
 		.nr_migratepages = 0,
 		.order = -1,
 		.zone = page_zone(pfn_to_page(start)),
-		.mode = COMPACT_SYNC,
+		.sync = true,
 	};
 	INIT_LIST_HEAD(&cc.migratepages);
 
diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
index 1ccbd714059c..eb750f851395 100644
--- a/mm/page_cgroup.c
+++ b/mm/page_cgroup.c
@@ -392,7 +392,7 @@ static struct swap_cgroup *lookup_swap_cgroup(swp_entry_t ent,
 
 /**
  * swap_cgroup_cmpxchg - cmpxchg mem_cgroup's id for this swp_entry.
- * @end: swap entry to be cmpxchged
+ * @ent: swap entry to be cmpxchged
  * @old: old id
  * @new: new id
  *
@@ -422,7 +422,7 @@ unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
 /**
  * swap_cgroup_record - record mem_cgroup for this swp_entry.
  * @ent: swap entry to be recorded into
- * @mem: mem_cgroup to be recorded
+ * @id: mem_cgroup to be recorded
  *
  * Returns old value at success, 0 at failure.
  * (Of course, old value can be 0.)
diff --git a/mm/page_io.c b/mm/page_io.c
index dc76b4d0611e..34f02923744c 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -18,6 +18,7 @@
 #include <linux/bio.h>
 #include <linux/swapops.h>
 #include <linux/writeback.h>
+#include <linux/frontswap.h>
 #include <asm/pgtable.h>
 
 static struct bio *get_swap_bio(gfp_t gfp_flags,
@@ -98,6 +99,12 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
 		unlock_page(page);
 		goto out;
 	}
+	if (frontswap_store(page) == 0) {
+		set_page_writeback(page);
+		unlock_page(page);
+		end_page_writeback(page);
+		goto out;
+	}
 	bio = get_swap_bio(GFP_NOIO, page, end_swap_bio_write);
 	if (bio == NULL) {
 		set_page_dirty(page);
@@ -122,6 +129,11 @@ int swap_readpage(struct page *page)
 
 	VM_BUG_ON(!PageLocked(page));
 	VM_BUG_ON(PageUptodate(page));
+	if (frontswap_load(page) == 0) {
+		SetPageUptodate(page);
+		unlock_page(page);
+		goto out;
+	}
 	bio = get_swap_bio(GFP_KERNEL, page, end_swap_bio_read);
 	if (bio == NULL) {
 		unlock_page(page);
diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index aa9701e12714..6c118d012bb5 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -162,7 +162,6 @@ static int walk_hugetlb_range(struct vm_area_struct *vma,
 
 /**
  * walk_page_range - walk a memory map's page tables with a callback
- * @mm: memory map to walk
  * @addr: starting address
  * @end: ending address
  * @walk: set of callbacks to invoke for each level of the tree
diff --git a/mm/percpu-vm.c b/mm/percpu-vm.c
index 405d331804c3..3707c71ae4cd 100644
--- a/mm/percpu-vm.c
+++ b/mm/percpu-vm.c
@@ -360,7 +360,6 @@ err_free:
  * @chunk: chunk to depopulate
  * @off: offset to the area to depopulate
  * @size: size of the area to depopulate in bytes
- * @flush: whether to flush cache and tlb or not
  *
  * For each cpu, depopulate and unmap pages [@page_start,@page_end)
  * from @chunk.  If @flush is true, vcache is flushed before unmapping
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index c20ff48994c2..926b46649749 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -371,15 +371,15 @@ static ssize_t process_vm_rw(pid_t pid,
 	/* Check iovecs */
 	if (vm_write)
 		rc = rw_copy_check_uvector(WRITE, lvec, liovcnt, UIO_FASTIOV,
-					   iovstack_l, &iov_l, 1);
+					   iovstack_l, &iov_l);
 	else
 		rc = rw_copy_check_uvector(READ, lvec, liovcnt, UIO_FASTIOV,
-					   iovstack_l, &iov_l, 1);
+					   iovstack_l, &iov_l);
 	if (rc <= 0)
 		goto free_iovecs;
 
-	rc = rw_copy_check_uvector(READ, rvec, riovcnt, UIO_FASTIOV,
-				   iovstack_r, &iov_r, 0);
+	rc = rw_copy_check_uvector(CHECK_IOVEC_ONLY, rvec, riovcnt, UIO_FASTIOV,
+				   iovstack_r, &iov_r);
 	if (rc <= 0)
 		goto free_iovecs;
 
@@ -438,16 +438,16 @@ compat_process_vm_rw(compat_pid_t pid,
 	if (vm_write)
 		rc = compat_rw_copy_check_uvector(WRITE, lvec, liovcnt,
 						  UIO_FASTIOV, iovstack_l,
-						  &iov_l, 1);
+						  &iov_l);
 	else
 		rc = compat_rw_copy_check_uvector(READ, lvec, liovcnt,
 						  UIO_FASTIOV, iovstack_l,
-						  &iov_l, 1);
+						  &iov_l);
 	if (rc <= 0)
 		goto free_iovecs;
-	rc = compat_rw_copy_check_uvector(READ, rvec, riovcnt,
+	rc = compat_rw_copy_check_uvector(CHECK_IOVEC_ONLY, rvec, riovcnt,
 					  UIO_FASTIOV, iovstack_r,
-					  &iov_r, 0);
+					  &iov_r);
 	if (rc <= 0)
 		goto free_iovecs;
 
diff --git a/mm/shmem.c b/mm/shmem.c
index d576b84d913c..a15a466d0d1d 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -683,10 +683,21 @@ static int shmem_unuse_inode(struct shmem_inode_info *info,
 		mutex_lock(&shmem_swaplist_mutex);
 		/*
 		 * We needed to drop mutex to make that restrictive page
-		 * allocation; but the inode might already be freed by now,
-		 * and we cannot refer to inode or mapping or info to check.
-		 * However, we do hold page lock on the PageSwapCache page,
-		 * so can check if that still has our reference remaining.
+		 * allocation, but the inode might have been freed while we
+		 * dropped it: although a racing shmem_evict_inode() cannot
+		 * complete without emptying the radix_tree, our page lock
+		 * on this swapcache page is not enough to prevent that -
+		 * free_swap_and_cache() of our swap entry will only
+		 * trylock_page(), removing swap from radix_tree whatever.
+		 *
+		 * We must not proceed to shmem_add_to_page_cache() if the
+		 * inode has been freed, but of course we cannot rely on
+		 * inode or mapping or info to check that.  However, we can
+		 * safely check if our swap entry is still in use (and here
+		 * it can't have got reused for another page): if it's still
+		 * in use, then the inode cannot have been freed yet, and we
+		 * can safely proceed (if it's no longer in use, that tells
+		 * nothing about the inode, but we don't need to unuse swap).
 		 */
 		if (!page_swapcount(*pagep))
 			error = -ENOENT;
@@ -730,9 +741,9 @@ int shmem_unuse(swp_entry_t swap, struct page *page)
 
 	/*
 	 * There's a faint possibility that swap page was replaced before
-	 * caller locked it: it will come back later with the right page.
+	 * caller locked it: caller will come back later with the right page.
 	 */
-	if (unlikely(!PageSwapCache(page)))
+	if (unlikely(!PageSwapCache(page) || page_private(page) != swap.val))
 		goto out;
 
 	/*
@@ -995,21 +1006,15 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
 	newpage = shmem_alloc_page(gfp, info, index);
 	if (!newpage)
 		return -ENOMEM;
-	VM_BUG_ON(shmem_should_replace_page(newpage, gfp));
 
-	*pagep = newpage;
 	page_cache_get(newpage);
 	copy_highpage(newpage, oldpage);
+	flush_dcache_page(newpage);
 
-	VM_BUG_ON(!PageLocked(oldpage));
 	__set_page_locked(newpage);
-	VM_BUG_ON(!PageUptodate(oldpage));
 	SetPageUptodate(newpage);
-	VM_BUG_ON(!PageSwapBacked(oldpage));
 	SetPageSwapBacked(newpage);
-	VM_BUG_ON(!swap_index);
 	set_page_private(newpage, swap_index);
-	VM_BUG_ON(!PageSwapCache(oldpage));
 	SetPageSwapCache(newpage);
 
 	/*
@@ -1019,13 +1024,24 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
 	spin_lock_irq(&swap_mapping->tree_lock);
 	error = shmem_radix_tree_replace(swap_mapping, swap_index, oldpage,
 								   newpage);
-	__inc_zone_page_state(newpage, NR_FILE_PAGES);
-	__dec_zone_page_state(oldpage, NR_FILE_PAGES);
+	if (!error) {
+		__inc_zone_page_state(newpage, NR_FILE_PAGES);
+		__dec_zone_page_state(oldpage, NR_FILE_PAGES);
+	}
 	spin_unlock_irq(&swap_mapping->tree_lock);
-	BUG_ON(error);
 
-	mem_cgroup_replace_page_cache(oldpage, newpage);
-	lru_cache_add_anon(newpage);
+	if (unlikely(error)) {
+		/*
+		 * Is this possible?  I think not, now that our callers check
+		 * both PageSwapCache and page_private after getting page lock;
+		 * but be defensive.  Reverse old to newpage for clear and free.
+		 */
+		oldpage = newpage;
+	} else {
+		mem_cgroup_replace_page_cache(oldpage, newpage);
+		lru_cache_add_anon(newpage);
+		*pagep = newpage;
+	}
 
 	ClearPageSwapCache(oldpage);
 	set_page_private(oldpage, 0);
@@ -1033,7 +1049,7 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
 	unlock_page(oldpage);
 	page_cache_release(oldpage);
 	page_cache_release(oldpage);
-	return 0;
+	return error;
 }
 
 /*
@@ -1107,7 +1123,8 @@ repeat:
 
 		/* We have to do this with page locked to prevent races */
 		lock_page(page);
-		if (!PageSwapCache(page) || page->mapping) {
+		if (!PageSwapCache(page) || page_private(page) != swap.val ||
+		    page->mapping) {
 			error = -EEXIST;	/* try again */
 			goto failed;
 		}
@@ -2439,11 +2456,9 @@ static struct dentry *shmem_fh_to_dentry(struct super_block *sb,
 	return dentry;
 }
 
-static int shmem_encode_fh(struct dentry *dentry, __u32 *fh, int *len,
-				int connectable)
+static int shmem_encode_fh(struct inode *inode, __u32 *fh, int *len,
+				struct inode *parent)
 {
-	struct inode *inode = dentry->d_inode;
-
 	if (*len < 3) {
 		*len = 3;
 		return 255;
diff --git a/mm/slub.c b/mm/slub.c
index 80848cd3901c..8c691fa1cf3c 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1369,7 +1369,7 @@ static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
 
 	inc_slabs_node(s, page_to_nid(page), page->objects);
 	page->slab = s;
-	page->flags |= 1 << PG_slab;
+	__SetPageSlab(page);
 
 	start = page_address(page);
 
@@ -1514,15 +1514,19 @@ static inline void *acquire_slab(struct kmem_cache *s,
 		freelist = page->freelist;
 		counters = page->counters;
 		new.counters = counters;
-		if (mode)
+		if (mode) {
 			new.inuse = page->objects;
+			new.freelist = NULL;
+		} else {
+			new.freelist = freelist;
+		}
 
 		VM_BUG_ON(new.frozen);
 		new.frozen = 1;
 
 	} while (!__cmpxchg_double_slab(s, page,
 			freelist, counters,
-			NULL, new.counters,
+			new.freelist, new.counters,
 			"lock and freeze"));
 
 	remove_partial(n, page);
@@ -1564,7 +1568,6 @@ static void *get_partial_node(struct kmem_cache *s,
 			object = t;
 			available =  page->objects - page->inuse;
 		} else {
-			page->freelist = t;
 			available = put_cpu_partial(s, page, 0);
 			stat(s, CPU_PARTIAL_NODE);
 		}
@@ -1579,7 +1582,7 @@ static void *get_partial_node(struct kmem_cache *s,
 /*
  * Get a page from somewhere. Search in increasing NUMA distances.
  */
-static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags,
+static void *get_any_partial(struct kmem_cache *s, gfp_t flags,
 		struct kmem_cache_cpu *c)
 {
 #ifdef CONFIG_NUMA
@@ -2766,7 +2769,7 @@ static unsigned long calculate_alignment(unsigned long flags,
 }
 
 static void
-init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s)
+init_kmem_cache_node(struct kmem_cache_node *n)
 {
 	n->nr_partial = 0;
 	spin_lock_init(&n->list_lock);
@@ -2836,7 +2839,7 @@ static void early_kmem_cache_node_alloc(int node)
 	init_object(kmem_cache_node, n, SLUB_RED_ACTIVE);
 	init_tracking(kmem_cache_node, n);
 #endif
-	init_kmem_cache_node(n, kmem_cache_node);
+	init_kmem_cache_node(n);
 	inc_slabs_node(kmem_cache_node, node, page->objects);
 
 	add_partial(n, page, DEACTIVATE_TO_HEAD);
@@ -2876,7 +2879,7 @@ static int init_kmem_cache_nodes(struct kmem_cache *s)
 		}
 
 		s->node[node] = n;
-		init_kmem_cache_node(n, s);
+		init_kmem_cache_node(n);
 	}
 	return 1;
 }
@@ -3625,7 +3628,7 @@ static int slab_mem_going_online_callback(void *arg)
 			ret = -ENOMEM;
 			goto out;
 		}
-		init_kmem_cache_node(n, s);
+		init_kmem_cache_node(n);
 		s->node[nid] = n;
 	}
 out:
@@ -3968,9 +3971,9 @@ struct kmem_cache *kmem_cache_create(const char *name, size_t size,
 			}
 			return s;
 		}
-		kfree(n);
 		kfree(s);
 	}
+	kfree(n);
 err:
 	up_write(&slub_lock);
 
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 457b10baef59..71373d03fcee 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -31,6 +31,8 @@
 #include <linux/memcontrol.h>
 #include <linux/poll.h>
 #include <linux/oom.h>
+#include <linux/frontswap.h>
+#include <linux/swapfile.h>
 
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
@@ -42,7 +44,7 @@ static bool swap_count_continued(struct swap_info_struct *, pgoff_t,
 static void free_swap_count_continuations(struct swap_info_struct *);
 static sector_t map_swap_entry(swp_entry_t, struct block_device**);
 
-static DEFINE_SPINLOCK(swap_lock);
+DEFINE_SPINLOCK(swap_lock);
 static unsigned int nr_swapfiles;
 long nr_swap_pages;
 long total_swap_pages;
@@ -53,9 +55,9 @@ static const char Unused_file[] = "Unused swap file entry ";
 static const char Bad_offset[] = "Bad swap offset entry ";
 static const char Unused_offset[] = "Unused swap offset entry ";
 
-static struct swap_list_t swap_list = {-1, -1};
+struct swap_list_t swap_list = {-1, -1};
 
-static struct swap_info_struct *swap_info[MAX_SWAPFILES];
+struct swap_info_struct *swap_info[MAX_SWAPFILES];
 
 static DEFINE_MUTEX(swapon_mutex);
 
@@ -556,6 +558,7 @@ static unsigned char swap_entry_free(struct swap_info_struct *p,
 			swap_list.next = p->type;
 		nr_swap_pages++;
 		p->inuse_pages--;
+		frontswap_invalidate_page(p->type, offset);
 		if ((p->flags & SWP_BLKDEV) &&
 				disk->fops->swap_slot_free_notify)
 			disk->fops->swap_slot_free_notify(p->bdev, offset);
@@ -985,11 +988,12 @@ static int unuse_mm(struct mm_struct *mm,
 }
 
 /*
- * Scan swap_map from current position to next entry still in use.
+ * Scan swap_map (or frontswap_map if frontswap parameter is true)
+ * from current position to next entry still in use.
  * Recycle to start on reaching the end, returning 0 when empty.
  */
 static unsigned int find_next_to_unuse(struct swap_info_struct *si,
-					unsigned int prev)
+					unsigned int prev, bool frontswap)
 {
 	unsigned int max = si->max;
 	unsigned int i = prev;
@@ -1015,6 +1019,12 @@ static unsigned int find_next_to_unuse(struct swap_info_struct *si,
 			prev = 0;
 			i = 1;
 		}
+		if (frontswap) {
+			if (frontswap_test(si, i))
+				break;
+			else
+				continue;
+		}
 		count = si->swap_map[i];
 		if (count && swap_count(count) != SWAP_MAP_BAD)
 			break;
@@ -1026,8 +1036,12 @@ static unsigned int find_next_to_unuse(struct swap_info_struct *si,
  * We completely avoid races by reading each swap page in advance,
  * and then search for the process using it.  All the necessary
  * page table adjustments can then be made atomically.
+ *
+ * if the boolean frontswap is true, only unuse pages_to_unuse pages;
+ * pages_to_unuse==0 means all pages; ignored if frontswap is false
  */
-static int try_to_unuse(unsigned int type)
+int try_to_unuse(unsigned int type, bool frontswap,
+		 unsigned long pages_to_unuse)
 {
 	struct swap_info_struct *si = swap_info[type];
 	struct mm_struct *start_mm;
@@ -1060,7 +1074,7 @@ static int try_to_unuse(unsigned int type)
 	 * one pass through swap_map is enough, but not necessarily:
 	 * there are races when an instance of an entry might be missed.
 	 */
-	while ((i = find_next_to_unuse(si, i)) != 0) {
+	while ((i = find_next_to_unuse(si, i, frontswap)) != 0) {
 		if (signal_pending(current)) {
 			retval = -EINTR;
 			break;
@@ -1227,6 +1241,10 @@ static int try_to_unuse(unsigned int type)
 		 * interactive performance.
 		 */
 		cond_resched();
+		if (frontswap && pages_to_unuse > 0) {
+			if (!--pages_to_unuse)
+				break;
+		}
 	}
 
 	mmput(start_mm);
@@ -1486,7 +1504,8 @@ bad_bmap:
 }
 
 static void enable_swap_info(struct swap_info_struct *p, int prio,
-				unsigned char *swap_map)
+				unsigned char *swap_map,
+				unsigned long *frontswap_map)
 {
 	int i, prev;
 
@@ -1496,6 +1515,7 @@ static void enable_swap_info(struct swap_info_struct *p, int prio,
 	else
 		p->prio = --least_priority;
 	p->swap_map = swap_map;
+	frontswap_map_set(p, frontswap_map);
 	p->flags |= SWP_WRITEOK;
 	nr_swap_pages += p->pages;
 	total_swap_pages += p->pages;
@@ -1512,6 +1532,7 @@ static void enable_swap_info(struct swap_info_struct *p, int prio,
 		swap_list.head = swap_list.next = p->type;
 	else
 		swap_info[prev]->next = p->type;
+	frontswap_init(p->type);
 	spin_unlock(&swap_lock);
 }
 
@@ -1585,7 +1606,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 	spin_unlock(&swap_lock);
 
 	oom_score_adj = test_set_oom_score_adj(OOM_SCORE_ADJ_MAX);
-	err = try_to_unuse(type);
+	err = try_to_unuse(type, false, 0); /* force all pages to be unused */
 	compare_swap_oom_score_adj(OOM_SCORE_ADJ_MAX, oom_score_adj);
 
 	if (err) {
@@ -1596,7 +1617,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 		 * sys_swapoff for this swap_info_struct at this point.
 		 */
 		/* re-insert swap space back into swap_list */
-		enable_swap_info(p, p->prio, p->swap_map);
+		enable_swap_info(p, p->prio, p->swap_map, frontswap_map_get(p));
 		goto out_dput;
 	}
 
@@ -1622,9 +1643,11 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 	swap_map = p->swap_map;
 	p->swap_map = NULL;
 	p->flags = 0;
+	frontswap_invalidate_area(type);
 	spin_unlock(&swap_lock);
 	mutex_unlock(&swapon_mutex);
 	vfree(swap_map);
+	vfree(frontswap_map_get(p));
 	/* Destroy swap account informatin */
 	swap_cgroup_swapoff(type);
 
@@ -1893,24 +1916,20 @@ static unsigned long read_swap_header(struct swap_info_struct *p,
 
 	/*
 	 * Find out how many pages are allowed for a single swap
-	 * device. There are three limiting factors: 1) the number
+	 * device. There are two limiting factors: 1) the number
 	 * of bits for the swap offset in the swp_entry_t type, and
 	 * 2) the number of bits in the swap pte as defined by the
-	 * the different architectures, and 3) the number of free bits
-	 * in an exceptional radix_tree entry. In order to find the
+	 * different architectures. In order to find the
 	 * largest possible bit mask, a swap entry with swap type 0
 	 * and swap offset ~0UL is created, encoded to a swap pte,
 	 * decoded to a swp_entry_t again, and finally the swap
 	 * offset is extracted. This will mask all the bits from
 	 * the initial ~0UL mask that can't be encoded in either
 	 * the swp_entry_t or the architecture definition of a
-	 * swap pte.  Then the same is done for a radix_tree entry.
+	 * swap pte.
 	 */
 	maxpages = swp_offset(pte_to_swp_entry(
-			swp_entry_to_pte(swp_entry(0, ~0UL))));
-	maxpages = swp_offset(radix_to_swp_entry(
-			swp_to_radix_entry(swp_entry(0, maxpages)))) + 1;
-
+			swp_entry_to_pte(swp_entry(0, ~0UL)))) + 1;
 	if (maxpages > swap_header->info.last_page) {
 		maxpages = swap_header->info.last_page + 1;
 		/* p->max is an unsigned int: don't overflow it */
@@ -1988,6 +2007,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 	sector_t span;
 	unsigned long maxpages;
 	unsigned char *swap_map = NULL;
+	unsigned long *frontswap_map = NULL;
 	struct page *page = NULL;
 	struct inode *inode = NULL;
 
@@ -2071,6 +2091,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 		error = nr_extents;
 		goto bad_swap;
 	}
+	/* frontswap enabled? set up bit-per-page map for frontswap */
+	if (frontswap_enabled)
+		frontswap_map = vzalloc(maxpages / sizeof(long));
 
 	if (p->bdev) {
 		if (blk_queue_nonrot(bdev_get_queue(p->bdev))) {
@@ -2086,14 +2109,15 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 	if (swap_flags & SWAP_FLAG_PREFER)
 		prio =
 		  (swap_flags & SWAP_FLAG_PRIO_MASK) >> SWAP_FLAG_PRIO_SHIFT;
-	enable_swap_info(p, prio, swap_map);
+	enable_swap_info(p, prio, swap_map, frontswap_map);
 
 	printk(KERN_INFO "Adding %uk swap on %s.  "
-			"Priority:%d extents:%d across:%lluk %s%s\n",
+			"Priority:%d extents:%d across:%lluk %s%s%s\n",
 		p->pages<<(PAGE_SHIFT-10), name, p->prio,
 		nr_extents, (unsigned long long)span<<(PAGE_SHIFT-10),
 		(p->flags & SWP_SOLIDSTATE) ? "SS" : "",
-		(p->flags & SWP_DISCARDABLE) ? "D" : "");
+		(p->flags & SWP_DISCARDABLE) ? "D" : "",
+		(frontswap_map) ? "FS" : "");
 
 	mutex_unlock(&swapon_mutex);
 	atomic_inc(&proc_poll_event);
diff --git a/mm/util.c b/mm/util.c
index ae962b31de88..8c7265afa29f 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -4,6 +4,7 @@
 #include <linux/export.h>
 #include <linux/err.h>
 #include <linux/sched.h>
+#include <linux/security.h>
 #include <asm/uaccess.h>
 
 #include "internal.h"
@@ -341,6 +342,35 @@ int __attribute__((weak)) get_user_pages_fast(unsigned long start,
 }
 EXPORT_SYMBOL_GPL(get_user_pages_fast);
 
+unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr,
+	unsigned long len, unsigned long prot,
+	unsigned long flag, unsigned long pgoff)
+{
+	unsigned long ret;
+	struct mm_struct *mm = current->mm;
+
+	ret = security_mmap_file(file, prot, flag);
+	if (!ret) {
+		down_write(&mm->mmap_sem);
+		ret = do_mmap_pgoff(file, addr, len, prot, flag, pgoff);
+		up_write(&mm->mmap_sem);
+	}
+	return ret;
+}
+
+unsigned long vm_mmap(struct file *file, unsigned long addr,
+	unsigned long len, unsigned long prot,
+	unsigned long flag, unsigned long offset)
+{
+	if (unlikely(offset + PAGE_ALIGN(len) < offset))
+		return -EINVAL;
+	if (unlikely(offset & ~PAGE_MASK))
+		return -EINVAL;
+
+	return vm_mmap_pgoff(file, addr, len, prot, flag, offset >> PAGE_SHIFT);
+}
+EXPORT_SYMBOL(vm_mmap);
+
 /* Tracepoints definitions. */
 EXPORT_TRACEPOINT_SYMBOL(kmalloc);
 EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);