diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c
index 63e5995..217b290 100644
--- a/fs/f2fs/acl.c
+++ b/fs/f2fs/acl.c
@@ -285,7 +285,7 @@ static int f2fs_acl_create_masq(struct posix_acl *acl, umode_t *mode_p)
 	/* assert(atomic_read(acl->a_refcount) == 1); */
 
 	FOREACH_ACL_ENTRY(pa, acl, pe) {
-		switch(pa->e_tag) {
+		switch (pa->e_tag) {
 		case ACL_USER_OBJ:
 			pa->e_perm &= (mode >> 6) | ~S_IRWXO;
 			mode &= (pa->e_perm << 6) | ~S_IRWXU;
@@ -326,7 +326,7 @@ static int f2fs_acl_create_masq(struct posix_acl *acl, umode_t *mode_p)
 	}
 
 	*mode_p = (*mode_p & ~S_IRWXUGO) | mode;
-        return not_equiv;
+	return not_equiv;
 }
 
 static int f2fs_acl_create(struct inode *dir, umode_t *mode,
diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index a98e1b0..ed70b68 100644
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -66,7 +66,7 @@ static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
 		.old_blkaddr = index,
 		.new_blkaddr = index,
 		.encrypted_page = NULL,
-		.is_meta = is_meta,
+		.is_por = !is_meta,
 	};
 	int err;
 
@@ -130,6 +130,30 @@ struct page *f2fs_get_tmp_page(struct f2fs_sb_info *sbi, pgoff_t index)
 	return __get_meta_page(sbi, index, false);
 }
 
+static bool __is_bitmap_valid(struct f2fs_sb_info *sbi, block_t blkaddr,
+							int type)
+{
+	struct seg_entry *se;
+	unsigned int segno, offset;
+	bool exist;
+
+	if (type != DATA_GENERIC_ENHANCE && type != DATA_GENERIC_ENHANCE_READ)
+		return true;
+
+	segno = GET_SEGNO(sbi, blkaddr);
+	offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
+	se = get_seg_entry(sbi, segno);
+
+	exist = f2fs_test_bit(offset, se->cur_valid_map);
+	if (!exist && type == DATA_GENERIC_ENHANCE) {
+		f2fs_msg(sbi->sb, KERN_ERR, "Inconsistent error "
+			"blkaddr:%u, sit bitmap:%d", blkaddr, exist);
+		set_sbi_flag(sbi, SBI_NEED_FSCK);
+		WARN_ON(1);
+	}
+	return exist;
+}
+
 bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi,
 					block_t blkaddr, int type)
 {
@@ -151,15 +175,22 @@ bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi,
 			return false;
 		break;
 	case META_POR:
+		if (unlikely(blkaddr >= MAX_BLKADDR(sbi) ||
+			blkaddr < MAIN_BLKADDR(sbi)))
+			return false;
+		break;
 	case DATA_GENERIC:
+	case DATA_GENERIC_ENHANCE:
+	case DATA_GENERIC_ENHANCE_READ:
 		if (unlikely(blkaddr >= MAX_BLKADDR(sbi) ||
-			blkaddr < MAIN_BLKADDR(sbi))) {
-			if (type == DATA_GENERIC) {
-				f2fs_msg(sbi->sb, KERN_WARNING,
-					"access invalid blkaddr:%u", blkaddr);
-				WARN_ON(1);
-			}
+				blkaddr < MAIN_BLKADDR(sbi))) {
+			f2fs_msg(sbi->sb, KERN_WARNING,
+				"access invalid blkaddr:%u", blkaddr);
+			set_sbi_flag(sbi, SBI_NEED_FSCK);
+			WARN_ON(1);
 			return false;
+		} else {
+			return __is_bitmap_valid(sbi, blkaddr, type);
 		}
 		break;
 	case META_GENERIC:
@@ -189,7 +220,7 @@ int f2fs_ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
 		.op_flags = sync ? (REQ_META | REQ_PRIO) : REQ_RAHEAD,
 		.encrypted_page = NULL,
 		.in_list = false,
-		.is_meta = (type != META_POR),
+		.is_por = (type == META_POR),
 	};
 	struct blk_plug plug;
 
@@ -644,6 +675,12 @@ int f2fs_recover_orphan_inodes(struct f2fs_sb_info *sbi)
 	if (!is_set_ckpt_flags(sbi, CP_ORPHAN_PRESENT_FLAG))
 		return 0;
 
+	if (bdev_read_only(sbi->sb->s_bdev)) {
+		f2fs_msg(sbi->sb, KERN_INFO, "write access "
+			"unavailable, skipping orphan cleanup");
+		return 0;
+	}
+
 	if (s_flags & SB_RDONLY) {
 		f2fs_msg(sbi->sb, KERN_INFO, "orphan cleanup on readonly fs");
 		sbi->sb->s_flags &= ~SB_RDONLY;
@@ -758,13 +795,27 @@ static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
 	}
 }
 
+static __u32 f2fs_checkpoint_chksum(struct f2fs_sb_info *sbi,
+						struct f2fs_checkpoint *ckpt)
+{
+	unsigned int chksum_ofs = le32_to_cpu(ckpt->checksum_offset);
+	__u32 chksum;
+
+	chksum = f2fs_crc32(sbi, ckpt, chksum_ofs);
+	if (chksum_ofs < CP_CHKSUM_OFFSET) {
+		chksum_ofs += sizeof(chksum);
+		chksum = f2fs_chksum(sbi, chksum, (__u8 *)ckpt + chksum_ofs,
+						F2FS_BLKSIZE - chksum_ofs);
+	}
+	return chksum;
+}
+
 static int get_checkpoint_version(struct f2fs_sb_info *sbi, block_t cp_addr,
 		struct f2fs_checkpoint **cp_block, struct page **cp_page,
 		unsigned long long *version)
 {
-	unsigned long blk_size = sbi->blocksize;
 	size_t crc_offset = 0;
-	__u32 crc = 0;
+	__u32 crc;
 
 	*cp_page = f2fs_get_meta_page(sbi, cp_addr);
 	if (IS_ERR(*cp_page))
@@ -773,15 +824,27 @@ static int get_checkpoint_version(struct f2fs_sb_info *sbi, block_t cp_addr,
 	*cp_block = (struct f2fs_checkpoint *)page_address(*cp_page);
 
 	crc_offset = le32_to_cpu((*cp_block)->checksum_offset);
-	if (crc_offset > (blk_size - sizeof(__le32))) {
+	if (crc_offset < CP_MIN_CHKSUM_OFFSET ||
+			crc_offset > CP_CHKSUM_OFFSET) {
 		f2fs_put_page(*cp_page, 1);
 		f2fs_msg(sbi->sb, KERN_WARNING,
 			"invalid crc_offset: %zu", crc_offset);
 		return -EINVAL;
 	}
 
-	crc = cur_cp_crc(*cp_block);
-	if (!f2fs_crc_valid(sbi, crc, *cp_block, crc_offset)) {
+	if (__is_set_ckpt_flags(*cp_block, CP_LARGE_NAT_BITMAP_FLAG)) {
+		if (crc_offset != CP_MIN_CHKSUM_OFFSET) {
+			f2fs_put_page(*cp_page, 1);
+			f2fs_msg(sbi->sb, KERN_WARNING,
+				"layout of large_nat_bitmap is deprecated, "
+				"run fsck to repair, chksum_offset: %zu",
+				crc_offset);
+			return -EINVAL;
+		}
+	}
+
+	crc = f2fs_checkpoint_chksum(sbi, *cp_block);
+	if (crc != cur_cp_crc(*cp_block)) {
 		f2fs_put_page(*cp_page, 1);
 		f2fs_msg(sbi->sb, KERN_WARNING, "invalid crc value");
 		return -EINVAL;
@@ -1009,13 +1072,11 @@ retry:
 	if (inode) {
 		unsigned long cur_ino = inode->i_ino;
 
-		if (is_dir)
-			F2FS_I(inode)->cp_task = current;
+		F2FS_I(inode)->cp_task = current;
 
 		filemap_fdatawrite(inode->i_mapping);
 
-		if (is_dir)
-			F2FS_I(inode)->cp_task = NULL;
+		F2FS_I(inode)->cp_task = NULL;
 
 		iput(inode);
 		/* We need to give cpu to another writers. */
@@ -1391,7 +1452,7 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 	get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
 	get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));
 
-	crc32 = f2fs_crc32(sbi, ckpt, le32_to_cpu(ckpt->checksum_offset));
+	crc32 = f2fs_checkpoint_chksum(sbi, ckpt);
 	*((__le32 *)((unsigned char *)ckpt +
 				le32_to_cpu(ckpt->checksum_offset)))
 				= cpu_to_le32(crc32);
@@ -1475,7 +1536,11 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 	clear_sbi_flag(sbi, SBI_IS_DIRTY);
 	clear_sbi_flag(sbi, SBI_NEED_CP);
 	clear_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH);
+
+	spin_lock(&sbi->stat_lock);
 	sbi->unusable_block_count = 0;
+	spin_unlock(&sbi->stat_lock);
+
 	__set_cp_next_pack(sbi);
 
 	/*
@@ -1500,6 +1565,9 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 	unsigned long long ckpt_ver;
 	int err = 0;
 
+	if (f2fs_readonly(sbi->sb) || f2fs_hw_is_readonly(sbi))
+		return -EROFS;
+
 	if (unlikely(is_sbi_flag_set(sbi, SBI_CP_DISABLED))) {
 		if (cpc->reason != CP_PAUSE)
 			return 0;
@@ -1516,10 +1584,6 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 		err = -EIO;
 		goto out;
 	}
-	if (f2fs_readonly(sbi->sb)) {
-		err = -EROFS;
-		goto out;
-	}
 
 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "start block_ops");
 
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 64040e9..eda4181 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -218,12 +218,14 @@ struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
 	struct block_device *bdev = sbi->sb->s_bdev;
 	int i;
 
-	for (i = 0; i < sbi->s_ndevs; i++) {
-		if (FDEV(i).start_blk <= blk_addr &&
-					FDEV(i).end_blk >= blk_addr) {
-			blk_addr -= FDEV(i).start_blk;
-			bdev = FDEV(i).bdev;
-			break;
+	if (f2fs_is_multi_device(sbi)) {
+		for (i = 0; i < sbi->s_ndevs; i++) {
+			if (FDEV(i).start_blk <= blk_addr &&
+			    FDEV(i).end_blk >= blk_addr) {
+				blk_addr -= FDEV(i).start_blk;
+				bdev = FDEV(i).bdev;
+				break;
+			}
 		}
 	}
 	if (bio) {
@@ -237,6 +239,9 @@ int f2fs_target_device_index(struct f2fs_sb_info *sbi, block_t blkaddr)
 {
 	int i;
 
+	if (!f2fs_is_multi_device(sbi))
+		return 0;
+
 	for (i = 0; i < sbi->s_ndevs; i++)
 		if (FDEV(i).start_blk <= blkaddr && FDEV(i).end_blk >= blkaddr)
 			return i;
@@ -420,7 +425,7 @@ static void __submit_merged_write_cond(struct f2fs_sb_info *sbi,
 
 void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type)
 {
-	__submit_merged_write_cond(sbi, NULL, 0, 0, type, true);
+	__submit_merged_write_cond(sbi, NULL, NULL, 0, type, true);
 }
 
 void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
@@ -448,7 +453,8 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 			fio->encrypted_page : fio->page;
 
 	if (!f2fs_is_valid_blkaddr(fio->sbi, fio->new_blkaddr,
-			__is_meta_io(fio) ? META_GENERIC : DATA_GENERIC))
+			fio->is_por ? META_POR : (__is_meta_io(fio) ?
+			META_GENERIC : DATA_GENERIC_ENHANCE)))
 		return -EFAULT;
 
 	trace_f2fs_submit_page_bio(page, fio);
@@ -498,9 +504,7 @@ next:
 		spin_unlock(&io->io_lock);
 	}
 
-	if (__is_valid_data_blkaddr(fio->old_blkaddr))
-		verify_block_addr(fio, fio->old_blkaddr);
-	verify_block_addr(fio, fio->new_blkaddr);
+	verify_fio_blkaddr(fio);
 
 	bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
 
@@ -557,9 +561,6 @@ static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
 	struct bio_post_read_ctx *ctx;
 	unsigned int post_read_steps = 0;
 
-	if (!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC))
-		return ERR_PTR(-EFAULT);
-
 	bio = f2fs_bio_alloc(sbi, min_t(int, nr_pages, BIO_MAX_PAGES), false);
 	if (!bio)
 		return ERR_PTR(-ENOMEM);
@@ -587,8 +588,10 @@ static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
 static int f2fs_submit_page_read(struct inode *inode, struct page *page,
 							block_t blkaddr)
 {
-	struct bio *bio = f2fs_grab_read_bio(inode, blkaddr, 1, 0);
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct bio *bio;
 
+	bio = f2fs_grab_read_bio(inode, blkaddr, 1, 0);
 	if (IS_ERR(bio))
 		return PTR_ERR(bio);
 
@@ -600,8 +603,8 @@ static int f2fs_submit_page_read(struct inode *inode, struct page *page,
 		return -EFAULT;
 	}
 	ClearPageError(page);
-	inc_page_count(F2FS_I_SB(inode), F2FS_RD_DATA);
-	__submit_bio(F2FS_I_SB(inode), bio, DATA);
+	inc_page_count(sbi, F2FS_RD_DATA);
+	__submit_bio(sbi, bio, DATA);
 	return 0;
 }
 
@@ -729,6 +732,11 @@ struct page *f2fs_get_read_data_page(struct inode *inode, pgoff_t index,
 
 	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 		dn.data_blkaddr = ei.blk + index - ei.fofs;
+		if (!f2fs_is_valid_blkaddr(F2FS_I_SB(inode), dn.data_blkaddr,
+						DATA_GENERIC_ENHANCE_READ)) {
+			err = -EFAULT;
+			goto put_err;
+		}
 		goto got_it;
 	}
 
@@ -742,6 +750,13 @@ struct page *f2fs_get_read_data_page(struct inode *inode, pgoff_t index,
 		err = -ENOENT;
 		goto put_err;
 	}
+	if (dn.data_blkaddr != NEW_ADDR &&
+			!f2fs_is_valid_blkaddr(F2FS_I_SB(inode),
+						dn.data_blkaddr,
+						DATA_GENERIC_ENHANCE)) {
+		err = -EFAULT;
+		goto put_err;
+	}
 got_it:
 	if (PageUptodate(page)) {
 		unlock_page(page);
@@ -1084,12 +1099,12 @@ next_block:
 	blkaddr = datablock_addr(dn.inode, dn.node_page, dn.ofs_in_node);
 
 	if (__is_valid_data_blkaddr(blkaddr) &&
-		!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC)) {
+		!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE)) {
 		err = -EFAULT;
 		goto sync_out;
 	}
 
-	if (is_valid_data_blkaddr(sbi, blkaddr)) {
+	if (__is_valid_data_blkaddr(blkaddr)) {
 		/* use out-place-update for driect IO under LFS mode */
 		if (test_opt(sbi, LFS) && flag == F2FS_GET_BLOCK_DIO &&
 							map->m_may_create) {
@@ -1499,6 +1514,118 @@ out:
 	return ret;
 }
 
+static int f2fs_read_single_page(struct inode *inode, struct page *page,
+					unsigned nr_pages,
+					struct f2fs_map_blocks *map,
+					struct bio **bio_ret,
+					sector_t *last_block_in_bio,
+					bool is_readahead)
+{
+	struct bio *bio = *bio_ret;
+	const unsigned blkbits = inode->i_blkbits;
+	const unsigned blocksize = 1 << blkbits;
+	sector_t block_in_file;
+	sector_t last_block;
+	sector_t last_block_in_file;
+	sector_t block_nr;
+	int ret = 0;
+
+	block_in_file = (sector_t)page->index;
+	last_block = block_in_file + nr_pages;
+	last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
+							blkbits;
+	if (last_block > last_block_in_file)
+		last_block = last_block_in_file;
+
+	/* just zeroing out page which is beyond EOF */
+	if (block_in_file >= last_block)
+		goto zero_out;
+	/*
+	 * Map blocks using the previous result first.
+	 */
+	if ((map->m_flags & F2FS_MAP_MAPPED) &&
+			block_in_file > map->m_lblk &&
+			block_in_file < (map->m_lblk + map->m_len))
+		goto got_it;
+
+	/*
+	 * Then do more f2fs_map_blocks() calls until we are
+	 * done with this page.
+	 */
+	map->m_lblk = block_in_file;
+	map->m_len = last_block - block_in_file;
+
+	ret = f2fs_map_blocks(inode, map, 0, F2FS_GET_BLOCK_DEFAULT);
+	if (ret)
+		goto out;
+got_it:
+	if ((map->m_flags & F2FS_MAP_MAPPED)) {
+		block_nr = map->m_pblk + block_in_file - map->m_lblk;
+		SetPageMappedToDisk(page);
+
+		if (!PageUptodate(page) && !cleancache_get_page(page)) {
+			SetPageUptodate(page);
+			goto confused;
+		}
+
+		if (!f2fs_is_valid_blkaddr(F2FS_I_SB(inode), block_nr,
+						DATA_GENERIC_ENHANCE_READ)) {
+			ret = -EFAULT;
+			goto out;
+		}
+	} else {
+zero_out:
+		zero_user_segment(page, 0, PAGE_SIZE);
+		if (!PageUptodate(page))
+			SetPageUptodate(page);
+		unlock_page(page);
+		goto out;
+	}
+
+	/*
+	 * This page will go to BIO.  Do we need to send this
+	 * BIO off first?
+	 */
+	if (bio && (*last_block_in_bio != block_nr - 1 ||
+		!__same_bdev(F2FS_I_SB(inode), block_nr, bio))) {
+submit_and_realloc:
+		__submit_bio(F2FS_I_SB(inode), bio, DATA);
+		bio = NULL;
+	}
+	if (bio == NULL) {
+		bio = f2fs_grab_read_bio(inode, block_nr, nr_pages,
+				is_readahead ? REQ_RAHEAD : 0);
+		if (IS_ERR(bio)) {
+			ret = PTR_ERR(bio);
+			bio = NULL;
+			goto out;
+		}
+	}
+
+	/*
+	 * If the page is under writeback, we need to wait for
+	 * its completion to see the correct decrypted data.
+	 */
+	f2fs_wait_on_block_writeback(inode, block_nr);
+
+	if (bio_add_page(bio, page, blocksize, 0) < blocksize)
+		goto submit_and_realloc;
+
+	inc_page_count(F2FS_I_SB(inode), F2FS_RD_DATA);
+	ClearPageError(page);
+	*last_block_in_bio = block_nr;
+	goto out;
+confused:
+	if (bio) {
+		__submit_bio(F2FS_I_SB(inode), bio, DATA);
+		bio = NULL;
+	}
+	unlock_page(page);
+out:
+	*bio_ret = bio;
+	return ret;
+}
+
 /*
  * This function was originally taken from fs/mpage.c, and customized for f2fs.
  * Major change was from block_size == page_size in f2fs by default.
@@ -1515,13 +1642,8 @@ static int f2fs_mpage_readpages(struct address_space *mapping,
 	struct bio *bio = NULL;
 	sector_t last_block_in_bio = 0;
 	struct inode *inode = mapping->host;
-	const unsigned blkbits = inode->i_blkbits;
-	const unsigned blocksize = 1 << blkbits;
-	sector_t block_in_file;
-	sector_t last_block;
-	sector_t last_block_in_file;
-	sector_t block_nr;
 	struct f2fs_map_blocks map;
+	int ret = 0;
 
 	map.m_pblk = 0;
 	map.m_lblk = 0;
@@ -1544,98 +1666,13 @@ static int f2fs_mpage_readpages(struct address_space *mapping,
 				goto next_page;
 		}
 
-		block_in_file = (sector_t)page->index;
-		last_block = block_in_file + nr_pages;
-		last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
-								blkbits;
-		if (last_block > last_block_in_file)
-			last_block = last_block_in_file;
-
-		/* just zeroing out page which is beyond EOF */
-		if (block_in_file >= last_block)
-			goto zero_out;
-		/*
-		 * Map blocks using the previous result first.
-		 */
-		if ((map.m_flags & F2FS_MAP_MAPPED) &&
-				block_in_file > map.m_lblk &&
-				block_in_file < (map.m_lblk + map.m_len))
-			goto got_it;
-
-		/*
-		 * Then do more f2fs_map_blocks() calls until we are
-		 * done with this page.
-		 */
-		map.m_lblk = block_in_file;
-		map.m_len = last_block - block_in_file;
-
-		if (f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DEFAULT))
-			goto set_error_page;
-got_it:
-		if ((map.m_flags & F2FS_MAP_MAPPED)) {
-			block_nr = map.m_pblk + block_in_file - map.m_lblk;
-			SetPageMappedToDisk(page);
-
-			if (!PageUptodate(page) && !cleancache_get_page(page)) {
-				SetPageUptodate(page);
-				goto confused;
-			}
-
-			if (!f2fs_is_valid_blkaddr(F2FS_I_SB(inode), block_nr,
-								DATA_GENERIC))
-				goto set_error_page;
-		} else {
-zero_out:
+		ret = f2fs_read_single_page(inode, page, nr_pages, &map, &bio,
+					&last_block_in_bio, is_readahead);
+		if (ret) {
+			SetPageError(page);
 			zero_user_segment(page, 0, PAGE_SIZE);
-			if (!PageUptodate(page))
-				SetPageUptodate(page);
 			unlock_page(page);
-			goto next_page;
 		}
-
-		/*
-		 * This page will go to BIO.  Do we need to send this
-		 * BIO off first?
-		 */
-		if (bio && (last_block_in_bio != block_nr - 1 ||
-			!__same_bdev(F2FS_I_SB(inode), block_nr, bio))) {
-submit_and_realloc:
-			__submit_bio(F2FS_I_SB(inode), bio, DATA);
-			bio = NULL;
-		}
-		if (bio == NULL) {
-			bio = f2fs_grab_read_bio(inode, block_nr, nr_pages,
-					is_readahead ? REQ_RAHEAD : 0);
-			if (IS_ERR(bio)) {
-				bio = NULL;
-				goto set_error_page;
-			}
-		}
-
-		/*
-		 * If the page is under writeback, we need to wait for
-		 * its completion to see the correct decrypted data.
-		 */
-		f2fs_wait_on_block_writeback(inode, block_nr);
-
-		if (bio_add_page(bio, page, blocksize, 0) < blocksize)
-			goto submit_and_realloc;
-
-		inc_page_count(F2FS_I_SB(inode), F2FS_RD_DATA);
-		ClearPageError(page);
-		last_block_in_bio = block_nr;
-		goto next_page;
-set_error_page:
-		SetPageError(page);
-		zero_user_segment(page, 0, PAGE_SIZE);
-		unlock_page(page);
-		goto next_page;
-confused:
-		if (bio) {
-			__submit_bio(F2FS_I_SB(inode), bio, DATA);
-			bio = NULL;
-		}
-		unlock_page(page);
 next_page:
 		if (pages)
 			put_page(page);
@@ -1643,7 +1680,7 @@ next_page:
 	BUG_ON(pages && !list_empty(pages));
 	if (bio)
 		__submit_bio(F2FS_I_SB(inode), bio, DATA);
-	return 0;
+	return pages ? 0 : ret;
 }
 
 static int f2fs_read_data_page(struct file *file, struct page *page)
@@ -1813,7 +1850,7 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
 		fio->old_blkaddr = ei.blk + page->index - ei.fofs;
 
 		if (!f2fs_is_valid_blkaddr(fio->sbi, fio->old_blkaddr,
-							DATA_GENERIC))
+						DATA_GENERIC_ENHANCE))
 			return -EFAULT;
 
 		ipu_force = true;
@@ -1840,7 +1877,7 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
 got_it:
 	if (__is_valid_data_blkaddr(fio->old_blkaddr) &&
 		!f2fs_is_valid_blkaddr(fio->sbi, fio->old_blkaddr,
-							DATA_GENERIC)) {
+						DATA_GENERIC_ENHANCE)) {
 		err = -EFAULT;
 		goto out_writepage;
 	}
@@ -1848,7 +1885,8 @@ got_it:
 	 * If current allocation needs SSR,
 	 * it had better in-place writes for updated data.
 	 */
-	if (ipu_force || (is_valid_data_blkaddr(fio->sbi, fio->old_blkaddr) &&
+	if (ipu_force ||
+		(__is_valid_data_blkaddr(fio->old_blkaddr) &&
 					need_inplace_update(fio))) {
 		err = encrypt_one_page(fio);
 		if (err)
@@ -1866,9 +1904,10 @@ got_it:
 									true);
 			if (PageWriteback(page))
 				end_page_writeback(page);
+		} else {
+			set_inode_flag(inode, FI_UPDATE_WRITE);
 		}
 		trace_f2fs_do_write_data_page(fio->page, IPU);
-		set_inode_flag(inode, FI_UPDATE_WRITE);
 		return err;
 	}
 
@@ -2030,7 +2069,8 @@ out:
 	}
 
 	unlock_page(page);
-	if (!S_ISDIR(inode->i_mode) && !IS_NOQUOTA(inode))
+	if (!S_ISDIR(inode->i_mode) && !IS_NOQUOTA(inode) &&
+					!F2FS_I(inode)->cp_task)
 		f2fs_balance_fs(sbi, need_balance_fs);
 
 	if (unlikely(f2fs_cp_error(sbi))) {
@@ -2491,6 +2531,11 @@ repeat:
 		zero_user_segment(page, 0, PAGE_SIZE);
 		SetPageUptodate(page);
 	} else {
+		if (!f2fs_is_valid_blkaddr(sbi, blkaddr,
+				DATA_GENERIC_ENHANCE_READ)) {
+			err = -EFAULT;
+			goto fail;
+		}
 		err = f2fs_submit_page_read(inode, page, blkaddr);
 		if (err)
 			goto fail;
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index bacf5c2..06b89a9 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -210,7 +210,14 @@ enum {
 	META_SSA,
 	META_MAX,
 	META_POR,
-	DATA_GENERIC,
+	DATA_GENERIC,		/* check range only */
+	DATA_GENERIC_ENHANCE,	/* strong check on range and segment bitmap */
+	DATA_GENERIC_ENHANCE_READ,	/*
+					 * strong check on range and segment
+					 * bitmap but no warning due to race
+					 * condition of read on truncated area
+					 * by extent_cache
+					 */
 	META_GENERIC,
 };
 
@@ -1041,7 +1048,7 @@ struct f2fs_io_info {
 	bool submitted;		/* indicate IO submission */
 	int need_lock;		/* indicate we need to lock cp_rwsem */
 	bool in_list;		/* indicate fio is in io_list */
-	bool is_meta;		/* indicate borrow meta inode mapping or not */
+	bool is_por;		/* indicate IO is from recovery or not */
 	bool retry;		/* need to reallocate block address */
 	enum iostat_type io_type;	/* io type */
 	struct writeback_control *io_wbc; /* writeback control */
@@ -1068,8 +1075,8 @@ struct f2fs_dev_info {
 	block_t start_blk;
 	block_t end_blk;
 #ifdef CONFIG_BLK_DEV_ZONED
-	unsigned int nr_blkz;			/* Total number of zones */
-	u8 *blkz_type;				/* Array of zones type */
+	unsigned int nr_blkz;		/* Total number of zones */
+	unsigned long *blkz_seq;	/* Bitmap indicating sequential zones */
 #endif
 };
 
@@ -1366,6 +1373,17 @@ static inline bool time_to_inject(struct f2fs_sb_info *sbi, int type)
 }
 #endif
 
+/*
+ * Test if the mounted volume is a multi-device volume.
+ *   - For a single regular disk volume, sbi->s_ndevs is 0.
+ *   - For a single zoned disk volume, sbi->s_ndevs is 1.
+ *   - For a multi-device volume, sbi->s_ndevs is always 2 or more.
+ */
+static inline bool f2fs_is_multi_device(struct f2fs_sb_info *sbi)
+{
+	return sbi->s_ndevs > 1;
+}
+
 /* For write statistics. Suppose sector size is 512 bytes,
  * and the return value is in kbytes. s is of struct f2fs_sb_info.
  */
@@ -1777,6 +1795,7 @@ enospc:
 	return -ENOSPC;
 }
 
+void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...);
 static inline void dec_valid_block_count(struct f2fs_sb_info *sbi,
 						struct inode *inode,
 						block_t count)
@@ -1785,13 +1804,21 @@ static inline void dec_valid_block_count(struct f2fs_sb_info *sbi,
 
 	spin_lock(&sbi->stat_lock);
 	f2fs_bug_on(sbi, sbi->total_valid_block_count < (block_t) count);
-	f2fs_bug_on(sbi, inode->i_blocks < sectors);
 	sbi->total_valid_block_count -= (block_t)count;
 	if (sbi->reserved_blocks &&
 		sbi->current_reserved_blocks < sbi->reserved_blocks)
 		sbi->current_reserved_blocks = min(sbi->reserved_blocks,
 					sbi->current_reserved_blocks + count);
 	spin_unlock(&sbi->stat_lock);
+	if (unlikely(inode->i_blocks < sectors)) {
+		f2fs_msg(sbi->sb, KERN_WARNING,
+			"Inconsistent i_blocks, ino:%lu, iblocks:%llu, sectors:%llu",
+			inode->i_ino,
+			(unsigned long long)inode->i_blocks,
+			(unsigned long long)sectors);
+		set_sbi_flag(sbi, SBI_NEED_FSCK);
+		return;
+	}
 	f2fs_i_blocks_write(inode, count, false, true);
 }
 
@@ -1889,7 +1916,11 @@ static inline void *__bitmap_ptr(struct f2fs_sb_info *sbi, int flag)
 	if (is_set_ckpt_flags(sbi, CP_LARGE_NAT_BITMAP_FLAG)) {
 		offset = (flag == SIT_BITMAP) ?
 			le32_to_cpu(ckpt->nat_ver_bitmap_bytesize) : 0;
-		return &ckpt->sit_nat_version_bitmap + offset;
+		/*
+		 * if large_nat_bitmap feature is enabled, leave checksum
+		 * protection for all nat/sit bitmaps.
+		 */
+		return &ckpt->sit_nat_version_bitmap + offset + sizeof(__le32);
 	}
 
 	if (__cp_payload(sbi) > 0) {
@@ -2008,7 +2039,6 @@ static inline void dec_valid_node_count(struct f2fs_sb_info *sbi,
 
 	f2fs_bug_on(sbi, !sbi->total_valid_block_count);
 	f2fs_bug_on(sbi, !sbi->total_valid_node_count);
-	f2fs_bug_on(sbi, !is_inode && !inode->i_blocks);
 
 	sbi->total_valid_node_count--;
 	sbi->total_valid_block_count--;
@@ -2018,10 +2048,19 @@ static inline void dec_valid_node_count(struct f2fs_sb_info *sbi,
 
 	spin_unlock(&sbi->stat_lock);
 
-	if (is_inode)
+	if (is_inode) {
 		dquot_free_inode(inode);
-	else
+	} else {
+		if (unlikely(inode->i_blocks == 0)) {
+			f2fs_msg(sbi->sb, KERN_WARNING,
+				"Inconsistent i_blocks, ino:%lu, iblocks:%llu",
+				inode->i_ino,
+				(unsigned long long)inode->i_blocks);
+			set_sbi_flag(sbi, SBI_NEED_FSCK);
+			return;
+		}
 		f2fs_i_blocks_write(inode, 1, false, true);
+	}
 }
 
 static inline unsigned int valid_node_count(struct f2fs_sb_info *sbi)
@@ -2545,7 +2584,14 @@ static inline int f2fs_has_inline_xattr(struct inode *inode)
 
 static inline unsigned int addrs_per_inode(struct inode *inode)
 {
-	return CUR_ADDRS_PER_INODE(inode) - get_inline_xattr_addrs(inode);
+	unsigned int addrs = CUR_ADDRS_PER_INODE(inode) -
+				get_inline_xattr_addrs(inode);
+	return ALIGN_DOWN(addrs, 1);
+}
+
+static inline unsigned int addrs_per_block(struct inode *inode)
+{
+	return ALIGN_DOWN(DEF_ADDRS_PER_BLOCK, 1);
 }
 
 static inline void *inline_xattr_addr(struct inode *inode, struct page *page)
@@ -2558,7 +2604,9 @@ static inline void *inline_xattr_addr(struct inode *inode, struct page *page)
 
 static inline int inline_xattr_size(struct inode *inode)
 {
-	return get_inline_xattr_addrs(inode) * sizeof(__le32);
+	if (f2fs_has_inline_xattr(inode))
+		return get_inline_xattr_addrs(inode) * sizeof(__le32);
+	return 0;
 }
 
 static inline int f2fs_has_inline_data(struct inode *inode)
@@ -2800,12 +2848,10 @@ static inline void f2fs_update_iostat(struct f2fs_sb_info *sbi,
 
 #define __is_large_section(sbi)		((sbi)->segs_per_sec > 1)
 
-#define __is_meta_io(fio) (PAGE_TYPE_OF_BIO((fio)->type) == META &&	\
-				(!is_read_io((fio)->op) || (fio)->is_meta))
+#define __is_meta_io(fio) (PAGE_TYPE_OF_BIO((fio)->type) == META)
 
 bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi,
 					block_t blkaddr, int type);
-void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...);
 static inline void verify_blkaddr(struct f2fs_sb_info *sbi,
 					block_t blkaddr, int type)
 {
@@ -2824,15 +2870,6 @@ static inline bool __is_valid_data_blkaddr(block_t blkaddr)
 	return true;
 }
 
-static inline bool is_valid_data_blkaddr(struct f2fs_sb_info *sbi,
-						block_t blkaddr)
-{
-	if (!__is_valid_data_blkaddr(blkaddr))
-		return false;
-	verify_blkaddr(sbi, blkaddr, DATA_GENERIC);
-	return true;
-}
-
 static inline void f2fs_set_page_private(struct page *page,
 						unsigned long data)
 {
@@ -3530,16 +3567,12 @@ F2FS_FEATURE_FUNCS(lost_found, LOST_FOUND);
 F2FS_FEATURE_FUNCS(sb_chksum, SB_CHKSUM);
 
 #ifdef CONFIG_BLK_DEV_ZONED
-static inline int get_blkz_type(struct f2fs_sb_info *sbi,
-			struct block_device *bdev, block_t blkaddr)
+static inline bool f2fs_blkz_is_seq(struct f2fs_sb_info *sbi, int devi,
+				    block_t blkaddr)
 {
 	unsigned int zno = blkaddr >> sbi->log_blocks_per_blkz;
-	int i;
 
-	for (i = 0; i < sbi->s_ndevs; i++)
-		if (FDEV(i).bdev == bdev)
-			return FDEV(i).blkz_type[zno];
-	return -EINVAL;
+	return test_bit(zno, FDEV(devi).blkz_seq);
 }
 #endif
 
@@ -3548,9 +3581,23 @@ static inline bool f2fs_hw_should_discard(struct f2fs_sb_info *sbi)
 	return f2fs_sb_has_blkzoned(sbi);
 }
 
+static inline bool f2fs_bdev_support_discard(struct block_device *bdev)
+{
+	return blk_queue_discard(bdev_get_queue(bdev)) ||
+	       bdev_is_zoned(bdev);
+}
+
 static inline bool f2fs_hw_support_discard(struct f2fs_sb_info *sbi)
 {
-	return blk_queue_discard(bdev_get_queue(sbi->sb->s_bdev));
+	int i;
+
+	if (!f2fs_is_multi_device(sbi))
+		return f2fs_bdev_support_discard(sbi->sb->s_bdev);
+
+	for (i = 0; i < sbi->s_ndevs; i++)
+		if (f2fs_bdev_support_discard(FDEV(i).bdev))
+			return true;
+	return false;
 }
 
 static inline bool f2fs_realtime_discard_enable(struct f2fs_sb_info *sbi)
@@ -3559,6 +3606,20 @@ static inline bool f2fs_realtime_discard_enable(struct f2fs_sb_info *sbi)
 					f2fs_hw_should_discard(sbi);
 }
 
+static inline bool f2fs_hw_is_readonly(struct f2fs_sb_info *sbi)
+{
+	int i;
+
+	if (!f2fs_is_multi_device(sbi))
+		return bdev_read_only(sbi->sb->s_bdev);
+
+	for (i = 0; i < sbi->s_ndevs; i++)
+		if (bdev_read_only(FDEV(i).bdev))
+			return true;
+	return false;
+}
+
+
 static inline void set_opt_mode(struct f2fs_sb_info *sbi, unsigned int mt)
 {
 	clear_opt(sbi, ADAPTIVE);
@@ -3614,7 +3675,7 @@ static inline bool f2fs_force_buffered_io(struct inode *inode,
 
 	if (f2fs_post_read_required(inode))
 		return true;
-	if (sbi->s_ndevs)
+	if (f2fs_is_multi_device(sbi))
 		return true;
 	/*
 	 * for blkzoned device, fallback direct IO to buffered IO, so
@@ -3651,4 +3712,4 @@ static inline bool is_journalled_quota(struct f2fs_sb_info *sbi)
 	return false;
 }
 
-#endif
+#endif /* _LINUX_F2FS_H */
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 5742ab8..45b45f3 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -39,6 +39,8 @@ static vm_fault_t f2fs_filemap_fault(struct vm_fault *vmf)
 	ret = filemap_fault(vmf);
 	up_read(&F2FS_I(inode)->i_mmap_sem);
 
+	trace_f2fs_filemap_fault(inode, vmf->pgoff, (unsigned long)ret);
+
 	return ret;
 }
 
@@ -356,7 +358,7 @@ static bool __found_offset(struct f2fs_sb_info *sbi, block_t blkaddr,
 	switch (whence) {
 	case SEEK_DATA:
 		if ((blkaddr == NEW_ADDR && dirty == pgofs) ||
-			is_valid_data_blkaddr(sbi, blkaddr))
+			__is_valid_data_blkaddr(blkaddr))
 			return true;
 		break;
 	case SEEK_HOLE:
@@ -422,7 +424,7 @@ static loff_t f2fs_seek_block(struct file *file, loff_t offset, int whence)
 
 			if (__is_valid_data_blkaddr(blkaddr) &&
 				!f2fs_is_valid_blkaddr(F2FS_I_SB(inode),
-						blkaddr, DATA_GENERIC)) {
+					blkaddr, DATA_GENERIC_ENHANCE)) {
 				f2fs_put_dnode(&dn);
 				goto fail;
 			}
@@ -523,7 +525,8 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count)
 		f2fs_set_data_blkaddr(dn);
 
 		if (__is_valid_data_blkaddr(blkaddr) &&
-			!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC))
+			!f2fs_is_valid_blkaddr(sbi, blkaddr,
+					DATA_GENERIC_ENHANCE))
 			continue;
 
 		f2fs_invalidate_blocks(sbi, blkaddr);
@@ -552,7 +555,7 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count)
 
 void f2fs_truncate_data_blocks(struct dnode_of_data *dn)
 {
-	f2fs_truncate_data_blocks_range(dn, ADDRS_PER_BLOCK);
+	f2fs_truncate_data_blocks_range(dn, ADDRS_PER_BLOCK(dn->inode));
 }
 
 static int truncate_partial_data_page(struct inode *inode, u64 from,
@@ -1006,7 +1009,8 @@ next_dnode:
 	} else if (ret == -ENOENT) {
 		if (dn.max_level == 0)
 			return -ENOENT;
-		done = min((pgoff_t)ADDRS_PER_BLOCK - dn.ofs_in_node, len);
+		done = min((pgoff_t)ADDRS_PER_BLOCK(inode) - dn.ofs_in_node,
+									len);
 		blkaddr += done;
 		do_replace += done;
 		goto next;
@@ -1017,6 +1021,14 @@ next_dnode:
 	for (i = 0; i < done; i++, blkaddr++, do_replace++, dn.ofs_in_node++) {
 		*blkaddr = datablock_addr(dn.inode,
 					dn.node_page, dn.ofs_in_node);
+
+		if (__is_valid_data_blkaddr(*blkaddr) &&
+			!f2fs_is_valid_blkaddr(sbi, *blkaddr,
+					DATA_GENERIC_ENHANCE)) {
+			f2fs_put_dnode(&dn);
+			return -EFAULT;
+		}
+
 		if (!f2fs_is_checkpointed_data(sbi, *blkaddr)) {
 
 			if (test_opt(sbi, LFS)) {
@@ -1157,7 +1169,7 @@ static int __exchange_data_block(struct inode *src_inode,
 	int ret;
 
 	while (len) {
-		olen = min((pgoff_t)4 * ADDRS_PER_BLOCK, len);
+		olen = min((pgoff_t)4 * ADDRS_PER_BLOCK(src_inode), len);
 
 		src_blkaddr = f2fs_kvzalloc(F2FS_I_SB(src_inode),
 					array_size(olen, sizeof(block_t)),
@@ -2573,10 +2585,10 @@ static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg)
 							sizeof(range)))
 		return -EFAULT;
 
-	if (sbi->s_ndevs <= 1 || sbi->s_ndevs - 1 <= range.dev_num ||
+	if (!f2fs_is_multi_device(sbi) || sbi->s_ndevs - 1 <= range.dev_num ||
 			__is_large_section(sbi)) {
 		f2fs_msg(sbi->sb, KERN_WARNING,
-			"Can't flush %u in %d for segs_per_sec %u != 1\n",
+			"Can't flush %u in %d for segs_per_sec %u != 1",
 				range.dev_num, sbi->s_ndevs,
 				sbi->segs_per_sec);
 		return -EINVAL;
@@ -2858,7 +2870,7 @@ int f2fs_pin_file_control(struct inode *inode, bool inc)
 
 	if (fi->i_gc_failures[GC_FAILURE_PIN] > sbi->gc_pin_file_threshold) {
 		f2fs_msg(sbi->sb, KERN_WARNING,
-			"%s: Enable GC = ino %lx after %x GC trials\n",
+			"%s: Enable GC = ino %lx after %x GC trials",
 			__func__, inode->i_ino,
 			fi->i_gc_failures[GC_FAILURE_PIN]);
 		clear_inode_flag(inode, FI_PIN_FILE);
@@ -3035,15 +3047,21 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	struct inode *inode = file_inode(file);
 	ssize_t ret;
 
-	if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
-		return -EIO;
+	if (unlikely(f2fs_cp_error(F2FS_I_SB(inode)))) {
+		ret = -EIO;
+		goto out;
+	}
 
-	if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT))
-		return -EINVAL;
+	if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) {
+		ret = -EINVAL;
+		goto out;
+	}
 
 	if (!inode_trylock(inode)) {
-		if (iocb->ki_flags & IOCB_NOWAIT)
-			return -EAGAIN;
+		if (iocb->ki_flags & IOCB_NOWAIT) {
+			ret = -EAGAIN;
+			goto out;
+		}
 		inode_lock(inode);
 	}
 
@@ -3056,19 +3074,16 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 		if (iov_iter_fault_in_readable(from, iov_iter_count(from)))
 			set_inode_flag(inode, FI_NO_PREALLOC);
 
-		if ((iocb->ki_flags & IOCB_NOWAIT) &&
-			(iocb->ki_flags & IOCB_DIRECT)) {
-				if (!f2fs_overwrite_io(inode, iocb->ki_pos,
+		if ((iocb->ki_flags & IOCB_NOWAIT)) {
+			if (!f2fs_overwrite_io(inode, iocb->ki_pos,
 						iov_iter_count(from)) ||
-					f2fs_has_inline_data(inode) ||
-					f2fs_force_buffered_io(inode,
-							iocb, from)) {
-						clear_inode_flag(inode,
-								FI_NO_PREALLOC);
-						inode_unlock(inode);
-						return -EAGAIN;
-				}
-
+				f2fs_has_inline_data(inode) ||
+				f2fs_force_buffered_io(inode, iocb, from)) {
+				clear_inode_flag(inode, FI_NO_PREALLOC);
+				inode_unlock(inode);
+				ret = -EAGAIN;
+				goto out;
+			}
 		} else {
 			preallocated = true;
 			target_size = iocb->ki_pos + iov_iter_count(from);
@@ -3077,7 +3092,8 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 			if (err) {
 				clear_inode_flag(inode, FI_NO_PREALLOC);
 				inode_unlock(inode);
-				return err;
+				ret = err;
+				goto out;
 			}
 		}
 		ret = __generic_file_write_iter(iocb, from);
@@ -3091,7 +3107,9 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 			f2fs_update_iostat(F2FS_I_SB(inode), APP_WRITE_IO, ret);
 	}
 	inode_unlock(inode);
-
+out:
+	trace_f2fs_file_write_iter(inode, iocb->ki_pos,
+					iov_iter_count(from), ret);
 	if (ret > 0)
 		ret = generic_write_sync(iocb, ret);
 	return ret;
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 195cf0f..963fb45 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -591,7 +591,7 @@ block_t f2fs_start_bidx_of_node(unsigned int node_ofs, struct inode *inode)
 		int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1);
 		bidx = node_ofs - 5 - dec;
 	}
-	return bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE(inode);
+	return bidx * ADDRS_PER_BLOCK(inode) + ADDRS_PER_INODE(inode);
 }
 
 static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
@@ -656,6 +656,11 @@ static int ra_data_block(struct inode *inode, pgoff_t index)
 
 	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 		dn.data_blkaddr = ei.blk + index - ei.fofs;
+		if (unlikely(!f2fs_is_valid_blkaddr(sbi, dn.data_blkaddr,
+						DATA_GENERIC_ENHANCE_READ))) {
+			err = -EFAULT;
+			goto put_page;
+		}
 		goto got_it;
 	}
 
@@ -665,8 +670,12 @@ static int ra_data_block(struct inode *inode, pgoff_t index)
 		goto put_page;
 	f2fs_put_dnode(&dn);
 
+	if (!__is_valid_data_blkaddr(dn.data_blkaddr)) {
+		err = -ENOENT;
+		goto put_page;
+	}
 	if (unlikely(!f2fs_is_valid_blkaddr(sbi, dn.data_blkaddr,
-						DATA_GENERIC))) {
+						DATA_GENERIC_ENHANCE))) {
 		err = -EFAULT;
 		goto put_page;
 	}
@@ -1175,6 +1184,7 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi,
 				"type [%d, %d] in SSA and SIT",
 				segno, type, GET_SUM_TYPE((&sum->footer)));
 			set_sbi_flag(sbi, SBI_NEED_FSCK);
+			f2fs_stop_checkpoint(sbi, false);
 			goto skip;
 		}
 
@@ -1346,7 +1356,7 @@ void f2fs_build_gc_manager(struct f2fs_sb_info *sbi)
 	sbi->gc_pin_file_threshold = DEF_GC_FAILED_PINNED_FILES;
 
 	/* give warm/cold data area from slower device */
-	if (sbi->s_ndevs && !__is_large_section(sbi))
+	if (f2fs_is_multi_device(sbi) && !__is_large_section(sbi))
 		SIT_I(sbi)->last_victim[ALLOC_NEXT] =
 				GET_SEGNO(sbi, FDEV(0).end_blk) + 1;
 }
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index bb6a152..404d246 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -420,6 +420,14 @@ static int f2fs_move_inline_dirents(struct inode *dir, struct page *ipage,
 	stat_dec_inline_dir(dir);
 	clear_inode_flag(dir, FI_INLINE_DENTRY);
 
+	/*
+	 * should retrieve reserved space which was used to keep
+	 * inline_dentry's structure for backward compatibility.
+	 */
+	if (!f2fs_sb_has_flexible_inline_xattr(F2FS_I_SB(dir)) &&
+			!f2fs_has_inline_xattr(dir))
+		F2FS_I(dir)->i_inline_xattr_size = 0;
+
 	f2fs_i_depth_write(dir, 1);
 	if (i_size_read(dir) < PAGE_SIZE)
 		f2fs_i_size_write(dir, PAGE_SIZE);
@@ -501,6 +509,15 @@ static int f2fs_move_rehashed_dirents(struct inode *dir, struct page *ipage,
 
 	stat_dec_inline_dir(dir);
 	clear_inode_flag(dir, FI_INLINE_DENTRY);
+
+	/*
+	 * should retrieve reserved space which was used to keep
+	 * inline_dentry's structure for backward compatibility.
+	 */
+	if (!f2fs_sb_has_flexible_inline_xattr(F2FS_I_SB(dir)) &&
+			!f2fs_has_inline_xattr(dir))
+		F2FS_I(dir)->i_inline_xattr_size = 0;
+
 	kvfree(backup_dentry);
 	return 0;
 recover:
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index e7f2e87..ccb0222 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -73,7 +73,7 @@ static int __written_first_block(struct f2fs_sb_info *sbi,
 
 	if (!__is_valid_data_blkaddr(addr))
 		return 1;
-	if (!f2fs_is_valid_blkaddr(sbi, addr, DATA_GENERIC))
+	if (!f2fs_is_valid_blkaddr(sbi, addr, DATA_GENERIC_ENHANCE))
 		return -EFAULT;
 	return 0;
 }
@@ -177,8 +177,8 @@ bool f2fs_inode_chksum_verify(struct f2fs_sb_info *sbi, struct page *page)
 
 	if (provided != calculated)
 		f2fs_msg(sbi->sb, KERN_WARNING,
-			"checksum invalid, ino = %x, %x vs. %x",
-			ino_of_node(page), provided, calculated);
+			"checksum invalid, nid = %lu, ino_of_node = %x, %x vs. %x",
+			page->index, ino_of_node(page), provided, calculated);
 
 	return provided == calculated;
 }
@@ -267,9 +267,10 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page)
 		struct extent_info *ei = &F2FS_I(inode)->extent_tree->largest;
 
 		if (ei->len &&
-			(!f2fs_is_valid_blkaddr(sbi, ei->blk, DATA_GENERIC) ||
+			(!f2fs_is_valid_blkaddr(sbi, ei->blk,
+						DATA_GENERIC_ENHANCE) ||
 			!f2fs_is_valid_blkaddr(sbi, ei->blk + ei->len - 1,
-							DATA_GENERIC))) {
+						DATA_GENERIC_ENHANCE))) {
 			set_sbi_flag(sbi, SBI_NEED_FSCK);
 			f2fs_msg(sbi->sb, KERN_WARNING,
 				"%s: inode (ino=%lx) extent info [%u, %u, %u] "
@@ -488,6 +489,7 @@ make_now:
 	return inode;
 
 bad_inode:
+	f2fs_inode_synced(inode);
 	iget_failed(inode);
 	trace_f2fs_iget_exit(inode, ret);
 	return ERR_PTR(ret);
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index c3e8a90..0f77f92 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -143,7 +143,7 @@ fail_drop:
 	return ERR_PTR(err);
 }
 
-static int is_extension_exist(const unsigned char *s, const char *sub)
+static inline int is_extension_exist(const unsigned char *s, const char *sub)
 {
 	size_t slen = strlen(s);
 	size_t sublen = strlen(sub);
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index d6e48a6..18a038a 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -454,7 +454,7 @@ static void set_node_addr(struct f2fs_sb_info *sbi, struct node_info *ni,
 			new_blkaddr == NULL_ADDR);
 	f2fs_bug_on(sbi, nat_get_blkaddr(e) == NEW_ADDR &&
 			new_blkaddr == NEW_ADDR);
-	f2fs_bug_on(sbi, is_valid_data_blkaddr(sbi, nat_get_blkaddr(e)) &&
+	f2fs_bug_on(sbi, __is_valid_data_blkaddr(nat_get_blkaddr(e)) &&
 			new_blkaddr == NEW_ADDR);
 
 	/* increment version no as node is removed */
@@ -465,7 +465,7 @@ static void set_node_addr(struct f2fs_sb_info *sbi, struct node_info *ni,
 
 	/* change address */
 	nat_set_blkaddr(e, new_blkaddr);
-	if (!is_valid_data_blkaddr(sbi, new_blkaddr))
+	if (!__is_valid_data_blkaddr(new_blkaddr))
 		set_nat_flag(e, IS_CHECKPOINTED, false);
 	__set_nat_cache_dirty(nm_i, e);
 
@@ -526,6 +526,7 @@ int f2fs_get_node_info(struct f2fs_sb_info *sbi, nid_t nid,
 	struct f2fs_nat_entry ne;
 	struct nat_entry *e;
 	pgoff_t index;
+	block_t blkaddr;
 	int i;
 
 	ni->nid = nid;
@@ -569,6 +570,11 @@ int f2fs_get_node_info(struct f2fs_sb_info *sbi, nid_t nid,
 	node_info_from_raw_nat(ni, &ne);
 	f2fs_put_page(page, 1);
 cache:
+	blkaddr = le32_to_cpu(ne.block_addr);
+	if (__is_valid_data_blkaddr(blkaddr) &&
+		!f2fs_is_valid_blkaddr(sbi, blkaddr, DATA_GENERIC_ENHANCE))
+		return -EFAULT;
+
 	/* cache nat entry */
 	cache_nat_entry(sbi, nid, &ne);
 	return 0;
@@ -600,9 +606,9 @@ static void f2fs_ra_node_pages(struct page *parent, int start, int n)
 pgoff_t f2fs_get_next_page_offset(struct dnode_of_data *dn, pgoff_t pgofs)
 {
 	const long direct_index = ADDRS_PER_INODE(dn->inode);
-	const long direct_blks = ADDRS_PER_BLOCK;
-	const long indirect_blks = ADDRS_PER_BLOCK * NIDS_PER_BLOCK;
-	unsigned int skipped_unit = ADDRS_PER_BLOCK;
+	const long direct_blks = ADDRS_PER_BLOCK(dn->inode);
+	const long indirect_blks = ADDRS_PER_BLOCK(dn->inode) * NIDS_PER_BLOCK;
+	unsigned int skipped_unit = ADDRS_PER_BLOCK(dn->inode);
 	int cur_level = dn->cur_level;
 	int max_level = dn->max_level;
 	pgoff_t base = 0;
@@ -638,9 +644,9 @@ static int get_node_path(struct inode *inode, long block,
 				int offset[4], unsigned int noffset[4])
 {
 	const long direct_index = ADDRS_PER_INODE(inode);
-	const long direct_blks = ADDRS_PER_BLOCK;
+	const long direct_blks = ADDRS_PER_BLOCK(inode);
 	const long dptrs_per_blk = NIDS_PER_BLOCK;
-	const long indirect_blks = ADDRS_PER_BLOCK * NIDS_PER_BLOCK;
+	const long indirect_blks = ADDRS_PER_BLOCK(inode) * NIDS_PER_BLOCK;
 	const long dindirect_blks = indirect_blks * NIDS_PER_BLOCK;
 	int n = 0;
 	int level = 0;
@@ -1181,8 +1187,14 @@ int f2fs_remove_inode_page(struct inode *inode)
 		f2fs_put_dnode(&dn);
 		return -EIO;
 	}
-	f2fs_bug_on(F2FS_I_SB(inode),
-			inode->i_blocks != 0 && inode->i_blocks != 8);
+
+	if (unlikely(inode->i_blocks != 0 && inode->i_blocks != 8)) {
+		f2fs_msg(F2FS_I_SB(inode)->sb, KERN_WARNING,
+			"Inconsistent i_blocks, ino:%lu, iblocks:%llu",
+			inode->i_ino,
+			(unsigned long long)inode->i_blocks);
+		set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK);
+	}
 
 	/* will put inode & node pages */
 	err = truncate_node(&dn);
@@ -1277,9 +1289,10 @@ static int read_node_page(struct page *page, int op_flags)
 	int err;
 
 	if (PageUptodate(page)) {
-#ifdef CONFIG_F2FS_CHECK_FS
-		f2fs_bug_on(sbi, !f2fs_inode_chksum_verify(sbi, page));
-#endif
+		if (!f2fs_inode_chksum_verify(sbi, page)) {
+			ClearPageUptodate(page);
+			return -EBADMSG;
+		}
 		return LOCKED_PAGE;
 	}
 
@@ -1543,7 +1556,8 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
 	}
 
 	if (__is_valid_data_blkaddr(ni.blk_addr) &&
-		!f2fs_is_valid_blkaddr(sbi, ni.blk_addr, DATA_GENERIC)) {
+		!f2fs_is_valid_blkaddr(sbi, ni.blk_addr,
+					DATA_GENERIC_ENHANCE)) {
 		up_read(&sbi->node_write);
 		goto redirty_out;
 	}
@@ -2078,6 +2092,9 @@ static bool add_free_nid(struct f2fs_sb_info *sbi,
 	if (unlikely(nid == 0))
 		return false;
 
+	if (unlikely(f2fs_check_nid_range(sbi, nid)))
+		return false;
+
 	i = f2fs_kmem_cache_alloc(free_nid_slab, GFP_NOFS);
 	i->nid = nid;
 	i->state = FREE_NID;
diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
index e3883db..e04f82b 100644
--- a/fs/f2fs/recovery.c
+++ b/fs/f2fs/recovery.c
@@ -325,8 +325,10 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head,
 			break;
 		}
 
-		if (!is_recoverable_dnode(page))
+		if (!is_recoverable_dnode(page)) {
+			f2fs_put_page(page, 1);
 			break;
+		}
 
 		if (!is_fsync_dnode(page))
 			goto next;
@@ -338,8 +340,10 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head,
 			if (!check_only &&
 					IS_INODE(page) && is_dent_dnode(page)) {
 				err = f2fs_recover_inode_page(sbi, page);
-				if (err)
+				if (err) {
+					f2fs_put_page(page, 1);
 					break;
+				}
 				quota_inode = true;
 			}
 
@@ -355,6 +359,7 @@ static int find_fsync_dnodes(struct f2fs_sb_info *sbi, struct list_head *head,
 					err = 0;
 					goto next;
 				}
+				f2fs_put_page(page, 1);
 				break;
 			}
 		}
@@ -370,6 +375,7 @@ next:
 				"%s: detect looped node chain, "
 				"blkaddr:%u, next:%u",
 				__func__, blkaddr, next_blkaddr_of_node(page));
+			f2fs_put_page(page, 1);
 			err = -EINVAL;
 			break;
 		}
@@ -380,7 +386,6 @@ next:
 
 		f2fs_ra_meta_pages_cond(sbi, blkaddr);
 	}
-	f2fs_put_page(page, 1);
 	return err;
 }
 
@@ -546,7 +551,15 @@ retry_dn:
 		goto err;
 
 	f2fs_bug_on(sbi, ni.ino != ino_of_node(page));
-	f2fs_bug_on(sbi, ofs_of_node(dn.node_page) != ofs_of_node(page));
+
+	if (ofs_of_node(dn.node_page) != ofs_of_node(page)) {
+		f2fs_msg(sbi->sb, KERN_WARNING,
+			"Inconsistent ofs_of_node, ino:%lu, ofs:%u, %u",
+			inode->i_ino, ofs_of_node(dn.node_page),
+			ofs_of_node(page));
+		err = -EFAULT;
+		goto err;
+	}
 
 	for (; start < end; start++, dn.ofs_in_node++) {
 		block_t src, dest;
@@ -554,6 +567,18 @@ retry_dn:
 		src = datablock_addr(dn.inode, dn.node_page, dn.ofs_in_node);
 		dest = datablock_addr(dn.inode, page, dn.ofs_in_node);
 
+		if (__is_valid_data_blkaddr(src) &&
+			!f2fs_is_valid_blkaddr(sbi, src, META_POR)) {
+			err = -EFAULT;
+			goto err;
+		}
+
+		if (__is_valid_data_blkaddr(dest) &&
+			!f2fs_is_valid_blkaddr(sbi, dest, META_POR)) {
+			err = -EFAULT;
+			goto err;
+		}
+
 		/* skip recovering if dest is the same as src */
 		if (src == dest)
 			continue;
@@ -666,8 +691,10 @@ static int recover_data(struct f2fs_sb_info *sbi, struct list_head *inode_list,
 		 */
 		if (IS_INODE(page)) {
 			err = recover_inode(entry->inode, page);
-			if (err)
+			if (err) {
+				f2fs_put_page(page, 1);
 				break;
+			}
 		}
 		if (entry->last_dentry == blkaddr) {
 			err = recover_dentry(entry->inode, page, dir_list);
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index aa7fe79..8dee063 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -580,7 +580,7 @@ static int submit_flush_wait(struct f2fs_sb_info *sbi, nid_t ino)
 	int ret = 0;
 	int i;
 
-	if (!sbi->s_ndevs)
+	if (!f2fs_is_multi_device(sbi))
 		return __submit_flush_wait(sbi, sbi->sb->s_bdev);
 
 	for (i = 0; i < sbi->s_ndevs; i++) {
@@ -648,7 +648,8 @@ int f2fs_issue_flush(struct f2fs_sb_info *sbi, nid_t ino)
 		return ret;
 	}
 
-	if (atomic_inc_return(&fcc->queued_flush) == 1 || sbi->s_ndevs > 1) {
+	if (atomic_inc_return(&fcc->queued_flush) == 1 ||
+	    f2fs_is_multi_device(sbi)) {
 		ret = submit_flush_wait(sbi, ino);
 		atomic_dec(&fcc->queued_flush);
 
@@ -754,7 +755,7 @@ int f2fs_flush_device_cache(struct f2fs_sb_info *sbi)
 {
 	int ret = 0, i;
 
-	if (!sbi->s_ndevs)
+	if (!f2fs_is_multi_device(sbi))
 		return 0;
 
 	for (i = 1; i < sbi->s_ndevs; i++) {
@@ -1367,9 +1368,12 @@ static int __queue_discard_cmd(struct f2fs_sb_info *sbi,
 {
 	block_t lblkstart = blkstart;
 
+	if (!f2fs_bdev_support_discard(bdev))
+		return 0;
+
 	trace_f2fs_queue_discard(bdev, blkstart, blklen);
 
-	if (sbi->s_ndevs) {
+	if (f2fs_is_multi_device(sbi)) {
 		int devi = f2fs_target_device_index(sbi, blkstart);
 
 		blkstart -= FDEV(devi).start_blk;
@@ -1732,42 +1736,36 @@ static int __f2fs_issue_discard_zone(struct f2fs_sb_info *sbi,
 	block_t lblkstart = blkstart;
 	int devi = 0;
 
-	if (sbi->s_ndevs) {
+	if (f2fs_is_multi_device(sbi)) {
 		devi = f2fs_target_device_index(sbi, blkstart);
+		if (blkstart < FDEV(devi).start_blk ||
+		    blkstart > FDEV(devi).end_blk) {
+			f2fs_msg(sbi->sb, KERN_ERR, "Invalid block %x",
+				 blkstart);
+			return -EIO;
+		}
 		blkstart -= FDEV(devi).start_blk;
 	}
 
-	/*
-	 * We need to know the type of the zone: for conventional zones,
-	 * use regular discard if the drive supports it. For sequential
-	 * zones, reset the zone write pointer.
-	 */
-	switch (get_blkz_type(sbi, bdev, blkstart)) {
-
-	case BLK_ZONE_TYPE_CONVENTIONAL:
-		if (!blk_queue_discard(bdev_get_queue(bdev)))
-			return 0;
-		return __queue_discard_cmd(sbi, bdev, lblkstart, blklen);
-	case BLK_ZONE_TYPE_SEQWRITE_REQ:
-	case BLK_ZONE_TYPE_SEQWRITE_PREF:
+	/* For sequential zones, reset the zone write pointer */
+	if (f2fs_blkz_is_seq(sbi, devi, blkstart)) {
 		sector = SECTOR_FROM_BLOCK(blkstart);
 		nr_sects = SECTOR_FROM_BLOCK(blklen);
 
 		if (sector & (bdev_zone_sectors(bdev) - 1) ||
 				nr_sects != bdev_zone_sectors(bdev)) {
-			f2fs_msg(sbi->sb, KERN_INFO,
-				"(%d) %s: Unaligned discard attempted (block %x + %x)",
+			f2fs_msg(sbi->sb, KERN_ERR,
+				"(%d) %s: Unaligned zone reset attempted (block %x + %x)",
 				devi, sbi->s_ndevs ? FDEV(devi).path: "",
 				blkstart, blklen);
 			return -EIO;
 		}
 		trace_f2fs_issue_reset_zone(bdev, blkstart);
-		return blkdev_reset_zones(bdev, sector,
-					  nr_sects, GFP_NOFS);
-	default:
-		/* Unknown zone type: broken device ? */
-		return -EIO;
+		return blkdev_reset_zones(bdev, sector, nr_sects, GFP_NOFS);
 	}
+
+	/* For conventional zones, use regular discard if supported */
+	return __queue_discard_cmd(sbi, bdev, lblkstart, blklen);
 }
 #endif
 
@@ -1775,8 +1773,7 @@ static int __issue_discard_async(struct f2fs_sb_info *sbi,
 		struct block_device *bdev, block_t blkstart, block_t blklen)
 {
 #ifdef CONFIG_BLK_DEV_ZONED
-	if (f2fs_sb_has_blkzoned(sbi) &&
-				bdev_zoned_model(bdev) != BLK_ZONED_NONE)
+	if (f2fs_sb_has_blkzoned(sbi) && bdev_is_zoned(bdev))
 		return __f2fs_issue_discard_zone(sbi, bdev, blkstart, blklen);
 #endif
 	return __queue_discard_cmd(sbi, bdev, blkstart, blklen);
@@ -2172,8 +2169,11 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
 			 * before, we must track that to know how much space we
 			 * really have.
 			 */
-			if (f2fs_test_bit(offset, se->ckpt_valid_map))
+			if (f2fs_test_bit(offset, se->ckpt_valid_map)) {
+				spin_lock(&sbi->stat_lock);
 				sbi->unusable_block_count++;
+				spin_unlock(&sbi->stat_lock);
+			}
 		}
 
 		if (f2fs_test_and_clear_bit(offset, se->discard_map))
@@ -2220,7 +2220,7 @@ bool f2fs_is_checkpointed_data(struct f2fs_sb_info *sbi, block_t blkaddr)
 	struct seg_entry *se;
 	bool is_cp = false;
 
-	if (!is_valid_data_blkaddr(sbi, blkaddr))
+	if (!__is_valid_data_blkaddr(blkaddr))
 		return true;
 
 	down_read(&sit_i->sentry_lock);
@@ -3089,7 +3089,7 @@ static void update_device_state(struct f2fs_io_info *fio)
 	struct f2fs_sb_info *sbi = fio->sbi;
 	unsigned int devidx;
 
-	if (!sbi->s_ndevs)
+	if (!f2fs_is_multi_device(sbi))
 		return;
 
 	devidx = f2fs_target_device_index(sbi, fio->new_blkaddr);
@@ -3187,13 +3187,18 @@ int f2fs_inplace_write_data(struct f2fs_io_info *fio)
 {
 	int err;
 	struct f2fs_sb_info *sbi = fio->sbi;
+	unsigned int segno;
 
 	fio->new_blkaddr = fio->old_blkaddr;
 	/* i/o temperature is needed for passing down write hints */
 	__get_segment_type(fio);
 
-	f2fs_bug_on(sbi, !IS_DATASEG(get_seg_entry(sbi,
-			GET_SEGNO(sbi, fio->new_blkaddr))->type));
+	segno = GET_SEGNO(sbi, fio->new_blkaddr);
+
+	if (!IS_DATASEG(get_seg_entry(sbi, segno)->type)) {
+		set_sbi_flag(sbi, SBI_NEED_FSCK);
+		return -EFAULT;
+	}
 
 	stat_inc_inplace_blocks(fio->sbi);
 
@@ -3336,7 +3341,7 @@ void f2fs_wait_on_block_writeback(struct inode *inode, block_t blkaddr)
 	if (!f2fs_post_read_required(inode))
 		return;
 
-	if (!is_valid_data_blkaddr(sbi, blkaddr))
+	if (!__is_valid_data_blkaddr(blkaddr))
 		return;
 
 	cpage = find_lock_page(META_MAPPING(sbi), blkaddr);
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 5c7ed04..429007b 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -82,7 +82,7 @@
 	(GET_SEGOFF_FROM_SEG0(sbi, blk_addr) & ((sbi)->blocks_per_seg - 1))
 
 #define GET_SEGNO(sbi, blk_addr)					\
-	((!is_valid_data_blkaddr(sbi, blk_addr)) ?			\
+	((!__is_valid_data_blkaddr(blk_addr)) ?			\
 	NULL_SEGNO : GET_L2R_SEGNO(FREE_I(sbi),			\
 		GET_SEGNO_FROM_SEG0(sbi, blk_addr)))
 #define BLKS_PER_SEC(sbi)					\
@@ -656,14 +656,15 @@ static inline void check_seg_range(struct f2fs_sb_info *sbi, unsigned int segno)
 	f2fs_bug_on(sbi, segno > TOTAL_SEGS(sbi) - 1);
 }
 
-static inline void verify_block_addr(struct f2fs_io_info *fio, block_t blk_addr)
+static inline void verify_fio_blkaddr(struct f2fs_io_info *fio)
 {
 	struct f2fs_sb_info *sbi = fio->sbi;
 
-	if (__is_meta_io(fio))
-		verify_blkaddr(sbi, blk_addr, META_GENERIC);
-	else
-		verify_blkaddr(sbi, blk_addr, DATA_GENERIC);
+	if (__is_valid_data_blkaddr(fio->old_blkaddr))
+		verify_blkaddr(sbi, fio->old_blkaddr, __is_meta_io(fio) ?
+					META_GENERIC : DATA_GENERIC);
+	verify_blkaddr(sbi, fio->new_blkaddr, __is_meta_io(fio) ?
+					META_GENERIC : DATA_GENERIC_ENHANCE);
 }
 
 /*
@@ -672,7 +673,6 @@ static inline void verify_block_addr(struct f2fs_io_info *fio, block_t blk_addr)
 static inline int check_block_count(struct f2fs_sb_info *sbi,
 		int segno, struct f2fs_sit_entry *raw_sit)
 {
-#ifdef CONFIG_F2FS_CHECK_FS
 	bool is_valid  = test_bit_le(0, raw_sit->valid_map) ? true : false;
 	int valid_blocks = 0;
 	int cur_pos = 0, next_pos;
@@ -699,7 +699,7 @@ static inline int check_block_count(struct f2fs_sb_info *sbi,
 		set_sbi_flag(sbi, SBI_NEED_FSCK);
 		return -EINVAL;
 	}
-#endif
+
 	/* check segment usage, and check boundary of a given segment number */
 	if (unlikely(GET_SIT_VBLOCKS(raw_sit) > sbi->blocks_per_seg
 					|| segno > TOTAL_SEGS(sbi) - 1)) {
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 4c55d2e..6b959bb 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1019,7 +1019,7 @@ static void destroy_device_list(struct f2fs_sb_info *sbi)
 	for (i = 0; i < sbi->s_ndevs; i++) {
 		blkdev_put(FDEV(i).bdev, FMODE_EXCL);
 #ifdef CONFIG_BLK_DEV_ZONED
-		kvfree(FDEV(i).blkz_type);
+		kvfree(FDEV(i).blkz_seq);
 #endif
 	}
 	kvfree(sbi->devs);
@@ -1221,10 +1221,13 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	buf->f_blocks = total_count - start_count;
 	buf->f_bfree = user_block_count - valid_user_blocks(sbi) -
 						sbi->current_reserved_blocks;
+
+	spin_lock(&sbi->stat_lock);
 	if (unlikely(buf->f_bfree <= sbi->unusable_block_count))
 		buf->f_bfree = 0;
 	else
 		buf->f_bfree -= sbi->unusable_block_count;
+	spin_unlock(&sbi->stat_lock);
 
 	if (buf->f_bfree > F2FS_OPTION(sbi).root_reserved_blocks)
 		buf->f_bavail = buf->f_bfree -
@@ -1499,9 +1502,15 @@ static int f2fs_disable_checkpoint(struct f2fs_sb_info *sbi)
 	mutex_lock(&sbi->gc_mutex);
 	cpc.reason = CP_PAUSE;
 	set_sbi_flag(sbi, SBI_CP_DISABLED);
-	f2fs_write_checkpoint(sbi, &cpc);
+	err = f2fs_write_checkpoint(sbi, &cpc);
+	if (err)
+		goto out_unlock;
 
+	spin_lock(&sbi->stat_lock);
 	sbi->unusable_block_count = 0;
+	spin_unlock(&sbi->stat_lock);
+
+out_unlock:
 	mutex_unlock(&sbi->gc_mutex);
 restore_flag:
 	sbi->sb->s_flags = s_flags;	/* Restore MS_RDONLY status */
@@ -2271,7 +2280,7 @@ static const struct export_operations f2fs_export_ops = {
 static loff_t max_file_blocks(void)
 {
 	loff_t result = 0;
-	loff_t leaf_count = ADDRS_PER_BLOCK;
+	loff_t leaf_count = DEF_ADDRS_PER_BLOCK;
 
 	/*
 	 * note: previously, result is equal to (DEF_ADDRS_PER_INODE -
@@ -2449,7 +2458,7 @@ static int sanity_check_raw_super(struct f2fs_sb_info *sbi,
 	/* Currently, support only 4KB page cache size */
 	if (F2FS_BLKSIZE != PAGE_SIZE) {
 		f2fs_msg(sb, KERN_INFO,
-			"Invalid page_cache_size (%lu), supports only 4KB\n",
+			"Invalid page_cache_size (%lu), supports only 4KB",
 			PAGE_SIZE);
 		return 1;
 	}
@@ -2458,7 +2467,7 @@ static int sanity_check_raw_super(struct f2fs_sb_info *sbi,
 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
 	if (blocksize != F2FS_BLKSIZE) {
 		f2fs_msg(sb, KERN_INFO,
-			"Invalid blocksize (%u), supports only 4KB\n",
+			"Invalid blocksize (%u), supports only 4KB",
 			blocksize);
 		return 1;
 	}
@@ -2466,7 +2475,7 @@ static int sanity_check_raw_super(struct f2fs_sb_info *sbi,
 	/* check log blocks per segment */
 	if (le32_to_cpu(raw_super->log_blocks_per_seg) != 9) {
 		f2fs_msg(sb, KERN_INFO,
-			"Invalid log blocks per segment (%u)\n",
+			"Invalid log blocks per segment (%u)",
 			le32_to_cpu(raw_super->log_blocks_per_seg));
 		return 1;
 	}
@@ -2587,7 +2596,8 @@ int f2fs_sanity_check_ckpt(struct f2fs_sb_info *sbi)
 	unsigned int log_blocks_per_seg;
 	unsigned int segment_count_main;
 	unsigned int cp_pack_start_sum, cp_payload;
-	block_t user_block_count;
+	block_t user_block_count, valid_user_blocks;
+	block_t avail_node_count, valid_node_count;
 	int i, j;
 
 	total = le32_to_cpu(raw_super->segment_count);
@@ -2622,6 +2632,24 @@ int f2fs_sanity_check_ckpt(struct f2fs_sb_info *sbi)
 		return 1;
 	}
 
+	valid_user_blocks = le64_to_cpu(ckpt->valid_block_count);
+	if (valid_user_blocks > user_block_count) {
+		f2fs_msg(sbi->sb, KERN_ERR,
+			"Wrong valid_user_blocks: %u, user_block_count: %u",
+			valid_user_blocks, user_block_count);
+		return 1;
+	}
+
+	valid_node_count = le32_to_cpu(ckpt->valid_node_count);
+	avail_node_count = sbi->total_node_count - sbi->nquota_files -
+						F2FS_RESERVED_NODE_NUM;
+	if (valid_node_count > avail_node_count) {
+		f2fs_msg(sbi->sb, KERN_ERR,
+			"Wrong valid_node_count: %u, avail_node_count: %u",
+			valid_node_count, avail_node_count);
+		return 1;
+	}
+
 	main_segs = le32_to_cpu(raw_super->segment_count_main);
 	blocks_per_seg = sbi->blocks_per_seg;
 
@@ -2793,9 +2821,11 @@ static int init_blkz_info(struct f2fs_sb_info *sbi, int devi)
 	if (nr_sectors & (bdev_zone_sectors(bdev) - 1))
 		FDEV(devi).nr_blkz++;
 
-	FDEV(devi).blkz_type = f2fs_kmalloc(sbi, FDEV(devi).nr_blkz,
-								GFP_KERNEL);
-	if (!FDEV(devi).blkz_type)
+	FDEV(devi).blkz_seq = f2fs_kzalloc(sbi,
+					BITS_TO_LONGS(FDEV(devi).nr_blkz)
+					* sizeof(unsigned long),
+					GFP_KERNEL);
+	if (!FDEV(devi).blkz_seq)
 		return -ENOMEM;
 
 #define F2FS_REPORT_NR_ZONES   4096
@@ -2822,7 +2852,8 @@ static int init_blkz_info(struct f2fs_sb_info *sbi, int devi)
 		}
 
 		for (i = 0; i < nr_zones; i++) {
-			FDEV(devi).blkz_type[n] = zones[i].type;
+			if (zones[i].type != BLK_ZONE_TYPE_CONVENTIONAL)
+				set_bit(n, FDEV(devi).blkz_seq);
 			sector += zones[i].len;
 			n++;
 		}
@@ -3105,7 +3136,7 @@ try_onemore:
 #ifndef CONFIG_BLK_DEV_ZONED
 	if (f2fs_sb_has_blkzoned(sbi)) {
 		f2fs_msg(sb, KERN_ERR,
-			 "Zoned block device support is not enabled\n");
+			 "Zoned block device support is not enabled");
 		err = -EOPNOTSUPP;
 		goto free_sb_buf;
 	}
@@ -3350,10 +3381,17 @@ try_onemore:
 		 * mount should be failed, when device has readonly mode, and
 		 * previous checkpoint was not done by clean system shutdown.
 		 */
-		if (bdev_read_only(sb->s_bdev) &&
-				!is_set_ckpt_flags(sbi, CP_UMOUNT_FLAG)) {
-			err = -EROFS;
-			goto free_meta;
+		if (f2fs_hw_is_readonly(sbi)) {
+			if (!is_set_ckpt_flags(sbi, CP_UMOUNT_FLAG)) {
+				err = -EROFS;
+				f2fs_msg(sb, KERN_ERR,
+					"Need to recover fsync data, but "
+					"write access unavailable");
+				goto free_meta;
+			}
+			f2fs_msg(sbi->sb, KERN_INFO, "write access "
+				"unavailable, skipping recovery");
+			goto reset_checkpoint;
 		}
 
 		if (need_fsck)
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index 848a785..e791741 100644
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -202,12 +202,17 @@ static inline const struct xattr_handler *f2fs_xattr_handler(int index)
 	return handler;
 }
 
-static struct f2fs_xattr_entry *__find_xattr(void *base_addr, int index,
-					size_t len, const char *name)
+static struct f2fs_xattr_entry *__find_xattr(void *base_addr,
+				void *last_base_addr, int index,
+				size_t len, const char *name)
 {
 	struct f2fs_xattr_entry *entry;
 
 	list_for_each_xattr(entry, base_addr) {
+		if ((void *)(entry) + sizeof(__u32) > last_base_addr ||
+			(void *)XATTR_NEXT_ENTRY(entry) > last_base_addr)
+			return NULL;
+
 		if (entry->e_name_index != index)
 			continue;
 		if (entry->e_name_len != len)
@@ -297,20 +302,22 @@ static int lookup_all_xattrs(struct inode *inode, struct page *ipage,
 				const char *name, struct f2fs_xattr_entry **xe,
 				void **base_addr, int *base_size)
 {
-	void *cur_addr, *txattr_addr, *last_addr = NULL;
+	void *cur_addr, *txattr_addr, *last_txattr_addr;
+	void *last_addr = NULL;
 	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
-	unsigned int size = xnid ? VALID_XATTR_BLOCK_SIZE : 0;
 	unsigned int inline_size = inline_xattr_size(inode);
 	int err = 0;
 
-	if (!size && !inline_size)
+	if (!xnid && !inline_size)
 		return -ENODATA;
 
-	*base_size = inline_size + size + XATTR_PADDING_SIZE;
+	*base_size = XATTR_SIZE(xnid, inode) + XATTR_PADDING_SIZE;
 	txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode), *base_size, GFP_NOFS);
 	if (!txattr_addr)
 		return -ENOMEM;
 
+	last_txattr_addr = (void *)txattr_addr + XATTR_SIZE(xnid, inode);
+
 	/* read from inline xattr */
 	if (inline_size) {
 		err = read_inline_xattr(inode, ipage, txattr_addr);
@@ -337,7 +344,11 @@ static int lookup_all_xattrs(struct inode *inode, struct page *ipage,
 	else
 		cur_addr = txattr_addr;
 
-	*xe = __find_xattr(cur_addr, index, len, name);
+	*xe = __find_xattr(cur_addr, last_txattr_addr, index, len, name);
+	if (!*xe) {
+		err = -EFAULT;
+		goto out;
+	}
 check:
 	if (IS_XATTR_LAST_ENTRY(*xe)) {
 		err = -ENODATA;
@@ -581,7 +592,8 @@ static int __f2fs_setxattr(struct inode *inode, int index,
 			struct page *ipage, int flags)
 {
 	struct f2fs_xattr_entry *here, *last;
-	void *base_addr;
+	void *base_addr, *last_base_addr;
+	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
 	int found, newsize;
 	size_t len;
 	__u32 new_hsize;
@@ -605,8 +617,14 @@ static int __f2fs_setxattr(struct inode *inode, int index,
 	if (error)
 		return error;
 
+	last_base_addr = (void *)base_addr + XATTR_SIZE(xnid, inode);
+
 	/* find entry with wanted name. */
-	here = __find_xattr(base_addr, index, len, name);
+	here = __find_xattr(base_addr, last_base_addr, index, len, name);
+	if (!here) {
+		error = -EFAULT;
+		goto exit;
+	}
 
 	found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1;
 
diff --git a/fs/f2fs/xattr.h b/fs/f2fs/xattr.h
index 9172ee0..a90920e 100644
--- a/fs/f2fs/xattr.h
+++ b/fs/f2fs/xattr.h
@@ -71,6 +71,8 @@ struct f2fs_xattr_entry {
 				entry = XATTR_NEXT_ENTRY(entry))
 #define VALID_XATTR_BLOCK_SIZE	(PAGE_SIZE - sizeof(struct node_footer))
 #define XATTR_PADDING_SIZE	(sizeof(__u32))
+#define XATTR_SIZE(x,i)		(((x) ? VALID_XATTR_BLOCK_SIZE : 0) +	\
+						(inline_xattr_size(i)))
 #define MIN_OFFSET(i)		XATTR_ALIGN(inline_xattr_size(i) +	\
 						VALID_XATTR_BLOCK_SIZE)
 
diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
index f574042..6555990 100644
--- a/include/linux/f2fs_fs.h
+++ b/include/linux/f2fs_fs.h
@@ -164,6 +164,10 @@ struct f2fs_checkpoint {
 	unsigned char sit_nat_version_bitmap[1];
 } __packed;
 
+#define CP_CHKSUM_OFFSET	4092	/* default chksum offset in checkpoint */
+#define CP_MIN_CHKSUM_OFFSET						\
+	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
+
 /*
  * For orphan inode management
  */
@@ -198,11 +202,12 @@ struct f2fs_extent {
 					get_extra_isize(inode))
 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
 #define ADDRS_PER_INODE(inode)	addrs_per_inode(inode)
-#define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
+#define DEF_ADDRS_PER_BLOCK	1018	/* Address Pointers in a Direct Block */
+#define ADDRS_PER_BLOCK(inode)	addrs_per_block(inode)
 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
 
 #define ADDRS_PER_PAGE(page, inode)	\
-	(IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK)
+	(IS_INODE(page) ? ADDRS_PER_INODE(inode) : ADDRS_PER_BLOCK(inode))
 
 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
@@ -267,7 +272,7 @@ struct f2fs_inode {
 } __packed;
 
 struct direct_node {
-	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
+	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
 } __packed;
 
 struct indirect_node {
diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h
index a3916b4..53b96f1 100644
--- a/include/trace/events/f2fs.h
+++ b/include/trace/events/f2fs.h
@@ -533,6 +533,37 @@ TRACE_EVENT(f2fs_truncate_partial_nodes,
 		__entry->err)
 );
 
+TRACE_EVENT(f2fs_file_write_iter,
+
+	TP_PROTO(struct inode *inode, unsigned long offset,
+		unsigned long length, int ret),
+
+	TP_ARGS(inode, offset, length, ret),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(unsigned long, offset)
+		__field(unsigned long, length)
+		__field(int,	ret)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->offset	= offset;
+		__entry->length	= length;
+		__entry->ret	= ret;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, "
+		"offset = %lu, length = %lu, written(err) = %d",
+		show_dev_ino(__entry),
+		__entry->offset,
+		__entry->length,
+		__entry->ret)
+);
+
 TRACE_EVENT(f2fs_map_blocks,
 	TP_PROTO(struct inode *inode, struct f2fs_map_blocks *map, int ret),
 
@@ -1253,6 +1284,32 @@ DEFINE_EVENT(f2fs__page, f2fs_commit_inmem_page,
 	TP_ARGS(page, type)
 );
 
+TRACE_EVENT(f2fs_filemap_fault,
+
+	TP_PROTO(struct inode *inode, pgoff_t index, unsigned long ret),
+
+	TP_ARGS(inode, index, ret),
+
+	TP_STRUCT__entry(
+		__field(dev_t,	dev)
+		__field(ino_t,	ino)
+		__field(pgoff_t, index)
+		__field(unsigned long, ret)
+	),
+
+	TP_fast_assign(
+		__entry->dev	= inode->i_sb->s_dev;
+		__entry->ino	= inode->i_ino;
+		__entry->index	= index;
+		__entry->ret	= ret;
+	),
+
+	TP_printk("dev = (%d,%d), ino = %lu, index = %lu, ret = %lx",
+		show_dev_ino(__entry),
+		(unsigned long)__entry->index,
+		__entry->ret)
+);
+
 TRACE_EVENT(f2fs_writepages,
 
 	TP_PROTO(struct inode *inode, struct writeback_control *wbc, int type),