Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2761 insertions, 0 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
new file mode 100644
index 000000000..c63f5e326
--- /dev/null
+++ b/fs/f2fs/data.c
@@ -0,0 +1,2761 @@
+/*
+ * fs/f2fs/data.c
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ *             http://www.samsung.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/fs.h>
+#include <linux/f2fs_fs.h>
+#include <linux/buffer_head.h>
+#include <linux/mpage.h>
+#include <linux/writeback.h>
+#include <linux/backing-dev.h>
+#include <linux/pagevec.h>
+#include <linux/blkdev.h>
+#include <linux/bio.h>
+#include <linux/prefetch.h>
+#include <linux/uio.h>
+#include <linux/cleancache.h>
+#include <linux/sched/signal.h>
+
+#include "f2fs.h"
+#include "node.h"
+#include "segment.h"
+#include "trace.h"
+#include <trace/events/f2fs.h>
+
+#define NUM_PREALLOC_POST_READ_CTXS	128
+
+static struct kmem_cache *bio_post_read_ctx_cache;
+static mempool_t *bio_post_read_ctx_pool;
+
+static bool __is_cp_guaranteed(struct page *page)
+{
+	struct address_space *mapping = page->mapping;
+	struct inode *inode;
+	struct f2fs_sb_info *sbi;
+
+	if (!mapping)
+		return false;
+
+	inode = mapping->host;
+	sbi = F2FS_I_SB(inode);
+
+	if (inode->i_ino == F2FS_META_INO(sbi) ||
+			inode->i_ino ==  F2FS_NODE_INO(sbi) ||
+			S_ISDIR(inode->i_mode) ||
+			(S_ISREG(inode->i_mode) &&
+			is_inode_flag_set(inode, FI_ATOMIC_FILE)) ||
+			is_cold_data(page))
+		return true;
+	return false;
+}
+
+/* postprocessing steps for read bios */
+enum bio_post_read_step {
+	STEP_INITIAL = 0,
+	STEP_DECRYPT,
+};
+
+struct bio_post_read_ctx {
+	struct bio *bio;
+	struct work_struct work;
+	unsigned int cur_step;
+	unsigned int enabled_steps;
+};
+
+static void __read_end_io(struct bio *bio)
+{
+	struct page *page;
+	struct bio_vec *bv;
+	int i;
+
+	bio_for_each_segment_all(bv, bio, i) {
+		page = bv->bv_page;
+
+		/* PG_error was set if any post_read step failed */
+		if (bio->bi_status || PageError(page)) {
+			ClearPageUptodate(page);
+			/* will re-read again later */
+			ClearPageError(page);
+		} else {
+			SetPageUptodate(page);
+		}
+		unlock_page(page);
+	}
+	if (bio->bi_private)
+		mempool_free(bio->bi_private, bio_post_read_ctx_pool);
+	bio_put(bio);
+}
+
+static void bio_post_read_processing(struct bio_post_read_ctx *ctx);
+
+static void decrypt_work(struct work_struct *work)
+{
+	struct bio_post_read_ctx *ctx =
+		container_of(work, struct bio_post_read_ctx, work);
+
+	fscrypt_decrypt_bio(ctx->bio);
+
+	bio_post_read_processing(ctx);
+}
+
+static void bio_post_read_processing(struct bio_post_read_ctx *ctx)
+{
+	switch (++ctx->cur_step) {
+	case STEP_DECRYPT:
+		if (ctx->enabled_steps & (1 << STEP_DECRYPT)) {
+			INIT_WORK(&ctx->work, decrypt_work);
+			fscrypt_enqueue_decrypt_work(&ctx->work);
+			return;
+		}
+		ctx->cur_step++;
+		/* fall-through */
+	default:
+		__read_end_io(ctx->bio);
+	}
+}
+
+static bool f2fs_bio_post_read_required(struct bio *bio)
+{
+	return bio->bi_private && !bio->bi_status;
+}
+
+static void f2fs_read_end_io(struct bio *bio)
+{
+	if (time_to_inject(F2FS_P_SB(bio_first_page_all(bio)), FAULT_IO)) {
+		f2fs_show_injection_info(FAULT_IO);
+		bio->bi_status = BLK_STS_IOERR;
+	}
+
+	if (f2fs_bio_post_read_required(bio)) {
+		struct bio_post_read_ctx *ctx = bio->bi_private;
+
+		ctx->cur_step = STEP_INITIAL;
+		bio_post_read_processing(ctx);
+		return;
+	}
+
+	__read_end_io(bio);
+}
+
+static void f2fs_write_end_io(struct bio *bio)
+{
+	struct f2fs_sb_info *sbi = bio->bi_private;
+	struct bio_vec *bvec;
+	int i;
+
+	bio_for_each_segment_all(bvec, bio, i) {
+		struct page *page = bvec->bv_page;
+		enum count_type type = WB_DATA_TYPE(page);
+
+		if (IS_DUMMY_WRITTEN_PAGE(page)) {
+			set_page_private(page, (unsigned long)NULL);
+			ClearPagePrivate(page);
+			unlock_page(page);
+			mempool_free(page, sbi->write_io_dummy);
+
+			if (unlikely(bio->bi_status))
+				f2fs_stop_checkpoint(sbi, true);
+			continue;
+		}
+
+		fscrypt_pullback_bio_page(&page, true);
+
+		if (unlikely(bio->bi_status)) {
+			mapping_set_error(page->mapping, -EIO);
+			if (type == F2FS_WB_CP_DATA)
+				f2fs_stop_checkpoint(sbi, true);
+		}
+
+		f2fs_bug_on(sbi, page->mapping == NODE_MAPPING(sbi) &&
+					page->index != nid_of_node(page));
+
+		dec_page_count(sbi, type);
+		if (f2fs_in_warm_node_list(sbi, page))
+			f2fs_del_fsync_node_entry(sbi, page);
+		clear_cold_data(page);
+		end_page_writeback(page);
+	}
+	if (!get_pages(sbi, F2FS_WB_CP_DATA) &&
+				wq_has_sleeper(&sbi->cp_wait))
+		wake_up(&sbi->cp_wait);
+
+	bio_put(bio);
+}
+
+/*
+ * Return true, if pre_bio's bdev is same as its target device.
+ */
+struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
+				block_t blk_addr, struct bio *bio)
+{
+	struct block_device *bdev = sbi->sb->s_bdev;
+	int i;
+
+	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) {
+		bio_set_dev(bio, bdev);
+		bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr);
+	}
+	return bdev;
+}
+
+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;
+	return 0;
+}
+
+static bool __same_bdev(struct f2fs_sb_info *sbi,
+				block_t blk_addr, struct bio *bio)
+{
+	struct block_device *b = f2fs_target_device(sbi, blk_addr, NULL);
+	return bio->bi_disk == b->bd_disk && bio->bi_partno == b->bd_partno;
+}
+
+/*
+ * Low-level block read/write IO operations.
+ */
+static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
+				struct writeback_control *wbc,
+				int npages, bool is_read,
+				enum page_type type, enum temp_type temp)
+{
+	struct bio *bio;
+
+	bio = f2fs_bio_alloc(sbi, npages, true);
+
+	f2fs_target_device(sbi, blk_addr, bio);
+	if (is_read) {
+		bio->bi_end_io = f2fs_read_end_io;
+		bio->bi_private = NULL;
+	} else {
+		bio->bi_end_io = f2fs_write_end_io;
+		bio->bi_private = sbi;
+		bio->bi_write_hint = f2fs_io_type_to_rw_hint(sbi, type, temp);
+	}
+	if (wbc)
+		wbc_init_bio(wbc, bio);
+
+	return bio;
+}
+
+static inline void __submit_bio(struct f2fs_sb_info *sbi,
+				struct bio *bio, enum page_type type)
+{
+	if (!is_read_io(bio_op(bio))) {
+		unsigned int start;
+
+		if (type != DATA && type != NODE)
+			goto submit_io;
+
+		if (test_opt(sbi, LFS) && current->plug)
+			blk_finish_plug(current->plug);
+
+		start = bio->bi_iter.bi_size >> F2FS_BLKSIZE_BITS;
+		start %= F2FS_IO_SIZE(sbi);
+
+		if (start == 0)
+			goto submit_io;
+
+		/* fill dummy pages */
+		for (; start < F2FS_IO_SIZE(sbi); start++) {
+			struct page *page =
+				mempool_alloc(sbi->write_io_dummy,
+					GFP_NOIO | __GFP_ZERO | __GFP_NOFAIL);
+			f2fs_bug_on(sbi, !page);
+
+			SetPagePrivate(page);
+			set_page_private(page, (unsigned long)DUMMY_WRITTEN_PAGE);
+			lock_page(page);
+			if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE)
+				f2fs_bug_on(sbi, 1);
+		}
+		/*
+		 * In the NODE case, we lose next block address chain. So, we
+		 * need to do checkpoint in f2fs_sync_file.
+		 */
+		if (type == NODE)
+			set_sbi_flag(sbi, SBI_NEED_CP);
+	}
+submit_io:
+	if (is_read_io(bio_op(bio)))
+		trace_f2fs_submit_read_bio(sbi->sb, type, bio);
+	else
+		trace_f2fs_submit_write_bio(sbi->sb, type, bio);
+	submit_bio(bio);
+}
+
+static void __submit_merged_bio(struct f2fs_bio_info *io)
+{
+	struct f2fs_io_info *fio = &io->fio;
+
+	if (!io->bio)
+		return;
+
+	bio_set_op_attrs(io->bio, fio->op, fio->op_flags);
+
+	if (is_read_io(fio->op))
+		trace_f2fs_prepare_read_bio(io->sbi->sb, fio->type, io->bio);
+	else
+		trace_f2fs_prepare_write_bio(io->sbi->sb, fio->type, io->bio);
+
+	__submit_bio(io->sbi, io->bio, fio->type);
+	io->bio = NULL;
+}
+
+static bool __has_merged_page(struct f2fs_bio_info *io,
+				struct inode *inode, nid_t ino, pgoff_t idx)
+{
+	struct bio_vec *bvec;
+	struct page *target;
+	int i;
+
+	if (!io->bio)
+		return false;
+
+	if (!inode && !ino)
+		return true;
+
+	bio_for_each_segment_all(bvec, io->bio, i) {
+
+		if (bvec->bv_page->mapping)
+			target = bvec->bv_page;
+		else
+			target = fscrypt_control_page(bvec->bv_page);
+
+		if (idx != target->index)
+			continue;
+
+		if (inode && inode == target->mapping->host)
+			return true;
+		if (ino && ino == ino_of_node(target))
+			return true;
+	}
+
+	return false;
+}
+
+static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
+				nid_t ino, pgoff_t idx, enum page_type type)
+{
+	enum page_type btype = PAGE_TYPE_OF_BIO(type);
+	enum temp_type temp;
+	struct f2fs_bio_info *io;
+	bool ret = false;
+
+	for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
+		io = sbi->write_io[btype] + temp;
+
+		down_read(&io->io_rwsem);
+		ret = __has_merged_page(io, inode, ino, idx);
+		up_read(&io->io_rwsem);
+
+		/* TODO: use HOT temp only for meta pages now. */
+		if (ret || btype == META)
+			break;
+	}
+	return ret;
+}
+
+static void __f2fs_submit_merged_write(struct f2fs_sb_info *sbi,
+				enum page_type type, enum temp_type temp)
+{
+	enum page_type btype = PAGE_TYPE_OF_BIO(type);
+	struct f2fs_bio_info *io = sbi->write_io[btype] + temp;
+
+	down_write(&io->io_rwsem);
+
+	/* change META to META_FLUSH in the checkpoint procedure */
+	if (type >= META_FLUSH) {
+		io->fio.type = META_FLUSH;
+		io->fio.op = REQ_OP_WRITE;
+		io->fio.op_flags = REQ_META | REQ_PRIO | REQ_SYNC;
+		if (!test_opt(sbi, NOBARRIER))
+			io->fio.op_flags |= REQ_PREFLUSH | REQ_FUA;
+	}
+	__submit_merged_bio(io);
+	up_write(&io->io_rwsem);
+}
+
+static void __submit_merged_write_cond(struct f2fs_sb_info *sbi,
+				struct inode *inode, nid_t ino, pgoff_t idx,
+				enum page_type type, bool force)
+{
+	enum temp_type temp;
+
+	if (!force && !has_merged_page(sbi, inode, ino, idx, type))
+		return;
+
+	for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
+
+		__f2fs_submit_merged_write(sbi, type, temp);
+
+		/* TODO: use HOT temp only for meta pages now. */
+		if (type >= META)
+			break;
+	}
+}
+
+void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type)
+{
+	__submit_merged_write_cond(sbi, NULL, 0, 0, type, true);
+}
+
+void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
+				struct inode *inode, nid_t ino, pgoff_t idx,
+				enum page_type type)
+{
+	__submit_merged_write_cond(sbi, inode, ino, idx, type, false);
+}
+
+void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi)
+{
+	f2fs_submit_merged_write(sbi, DATA);
+	f2fs_submit_merged_write(sbi, NODE);
+	f2fs_submit_merged_write(sbi, META);
+}
+
+/*
+ * Fill the locked page with data located in the block address.
+ * A caller needs to unlock the page on failure.
+ */
+int f2fs_submit_page_bio(struct f2fs_io_info *fio)
+{
+	struct bio *bio;
+	struct page *page = fio->encrypted_page ?
+			fio->encrypted_page : fio->page;
+
+	if (!f2fs_is_valid_blkaddr(fio->sbi, fio->new_blkaddr,
+			__is_meta_io(fio) ? META_GENERIC : DATA_GENERIC))
+		return -EFSCORRUPTED;
+
+	trace_f2fs_submit_page_bio(page, fio);
+	f2fs_trace_ios(fio, 0);
+
+	/* Allocate a new bio */
+	bio = __bio_alloc(fio->sbi, fio->new_blkaddr, fio->io_wbc,
+				1, is_read_io(fio->op), fio->type, fio->temp);
+
+	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+		bio_put(bio);
+		return -EFAULT;
+	}
+
+	if (fio->io_wbc && !is_read_io(fio->op))
+		wbc_account_io(fio->io_wbc, page, PAGE_SIZE);
+
+	bio_set_op_attrs(bio, fio->op, fio->op_flags);
+
+	if (!is_read_io(fio->op))
+		inc_page_count(fio->sbi, WB_DATA_TYPE(fio->page));
+
+	__submit_bio(fio->sbi, bio, fio->type);
+	return 0;
+}
+
+void f2fs_submit_page_write(struct f2fs_io_info *fio)
+{
+	struct f2fs_sb_info *sbi = fio->sbi;
+	enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
+	struct f2fs_bio_info *io = sbi->write_io[btype] + fio->temp;
+	struct page *bio_page;
+
+	f2fs_bug_on(sbi, is_read_io(fio->op));
+
+	down_write(&io->io_rwsem);
+next:
+	if (fio->in_list) {
+		spin_lock(&io->io_lock);
+		if (list_empty(&io->io_list)) {
+			spin_unlock(&io->io_lock);
+			goto out;
+		}
+		fio = list_first_entry(&io->io_list,
+						struct f2fs_io_info, list);
+		list_del(&fio->list);
+		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);
+
+	bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
+
+	/* set submitted = true as a return value */
+	fio->submitted = true;
+
+	inc_page_count(sbi, WB_DATA_TYPE(bio_page));
+
+	if (io->bio && (io->last_block_in_bio != fio->new_blkaddr - 1 ||
+	    (io->fio.op != fio->op || io->fio.op_flags != fio->op_flags) ||
+			!__same_bdev(sbi, fio->new_blkaddr, io->bio)))
+		__submit_merged_bio(io);
+alloc_new:
+	if (io->bio == NULL) {
+		if ((fio->type == DATA || fio->type == NODE) &&
+				fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
+			dec_page_count(sbi, WB_DATA_TYPE(bio_page));
+			fio->retry = true;
+			goto skip;
+		}
+		io->bio = __bio_alloc(sbi, fio->new_blkaddr, fio->io_wbc,
+						BIO_MAX_PAGES, false,
+						fio->type, fio->temp);
+		io->fio = *fio;
+	}
+
+	if (bio_add_page(io->bio, bio_page, PAGE_SIZE, 0) < PAGE_SIZE) {
+		__submit_merged_bio(io);
+		goto alloc_new;
+	}
+
+	if (fio->io_wbc)
+		wbc_account_io(fio->io_wbc, bio_page, PAGE_SIZE);
+
+	io->last_block_in_bio = fio->new_blkaddr;
+	f2fs_trace_ios(fio, 0);
+
+	trace_f2fs_submit_page_write(fio->page, fio);
+skip:
+	if (fio->in_list)
+		goto next;
+out:
+	if (is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN))
+		__submit_merged_bio(io);
+	up_write(&io->io_rwsem);
+}
+
+static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
+					unsigned nr_pages, unsigned op_flag)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct bio *bio;
+	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);
+	f2fs_target_device(sbi, blkaddr, bio);
+	bio->bi_end_io = f2fs_read_end_io;
+	bio_set_op_attrs(bio, REQ_OP_READ, op_flag);
+
+	if (f2fs_encrypted_file(inode))
+		post_read_steps |= 1 << STEP_DECRYPT;
+	if (post_read_steps) {
+		ctx = mempool_alloc(bio_post_read_ctx_pool, GFP_NOFS);
+		if (!ctx) {
+			bio_put(bio);
+			return ERR_PTR(-ENOMEM);
+		}
+		ctx->bio = bio;
+		ctx->enabled_steps = post_read_steps;
+		bio->bi_private = ctx;
+	}
+
+	return bio;
+}
+
+/* This can handle encryption stuffs */
+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);
+
+	if (IS_ERR(bio))
+		return PTR_ERR(bio);
+
+	/* wait for GCed page writeback via META_MAPPING */
+	f2fs_wait_on_block_writeback(inode, blkaddr);
+
+	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+		bio_put(bio);
+		return -EFAULT;
+	}
+	ClearPageError(page);
+	__submit_bio(F2FS_I_SB(inode), bio, DATA);
+	return 0;
+}
+
+static void __set_data_blkaddr(struct dnode_of_data *dn)
+{
+	struct f2fs_node *rn = F2FS_NODE(dn->node_page);
+	__le32 *addr_array;
+	int base = 0;
+
+	if (IS_INODE(dn->node_page) && f2fs_has_extra_attr(dn->inode))
+		base = get_extra_isize(dn->inode);
+
+	/* Get physical address of data block */
+	addr_array = blkaddr_in_node(rn);
+	addr_array[base + dn->ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
+}
+
+/*
+ * Lock ordering for the change of data block address:
+ * ->data_page
+ *  ->node_page
+ *    update block addresses in the node page
+ */
+void f2fs_set_data_blkaddr(struct dnode_of_data *dn)
+{
+	f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
+	__set_data_blkaddr(dn);
+	if (set_page_dirty(dn->node_page))
+		dn->node_changed = true;
+}
+
+void f2fs_update_data_blkaddr(struct dnode_of_data *dn, block_t blkaddr)
+{
+	dn->data_blkaddr = blkaddr;
+	f2fs_set_data_blkaddr(dn);
+	f2fs_update_extent_cache(dn);
+}
+
+/* dn->ofs_in_node will be returned with up-to-date last block pointer */
+int f2fs_reserve_new_blocks(struct dnode_of_data *dn, blkcnt_t count)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
+	int err;
+
+	if (!count)
+		return 0;
+
+	if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
+		return -EPERM;
+	if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
+		return err;
+
+	trace_f2fs_reserve_new_blocks(dn->inode, dn->nid,
+						dn->ofs_in_node, count);
+
+	f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
+
+	for (; count > 0; dn->ofs_in_node++) {
+		block_t blkaddr = datablock_addr(dn->inode,
+					dn->node_page, dn->ofs_in_node);
+		if (blkaddr == NULL_ADDR) {
+			dn->data_blkaddr = NEW_ADDR;
+			__set_data_blkaddr(dn);
+			count--;
+		}
+	}
+
+	if (set_page_dirty(dn->node_page))
+		dn->node_changed = true;
+	return 0;
+}
+
+/* Should keep dn->ofs_in_node unchanged */
+int f2fs_reserve_new_block(struct dnode_of_data *dn)
+{
+	unsigned int ofs_in_node = dn->ofs_in_node;
+	int ret;
+
+	ret = f2fs_reserve_new_blocks(dn, 1);
+	dn->ofs_in_node = ofs_in_node;
+	return ret;
+}
+
+int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
+{
+	bool need_put = dn->inode_page ? false : true;
+	int err;
+
+	err = f2fs_get_dnode_of_data(dn, index, ALLOC_NODE);
+	if (err)
+		return err;
+
+	if (dn->data_blkaddr == NULL_ADDR)
+		err = f2fs_reserve_new_block(dn);
+	if (err || need_put)
+		f2fs_put_dnode(dn);
+	return err;
+}
+
+int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index)
+{
+	struct extent_info ei  = {0,0,0};
+	struct inode *inode = dn->inode;
+
+	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
+		dn->data_blkaddr = ei.blk + index - ei.fofs;
+		return 0;
+	}
+
+	return f2fs_reserve_block(dn, index);
+}
+
+struct page *f2fs_get_read_data_page(struct inode *inode, pgoff_t index,
+						int op_flags, bool for_write)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct dnode_of_data dn;
+	struct page *page;
+	struct extent_info ei = {0,0,0};
+	int err;
+
+	page = f2fs_grab_cache_page(mapping, index, for_write);
+	if (!page)
+		return ERR_PTR(-ENOMEM);
+
+	if (f2fs_lookup_extent_cache(inode, index, &ei)) {
+		dn.data_blkaddr = ei.blk + index - ei.fofs;
+		goto got_it;
+	}
+
+	set_new_dnode(&dn, inode, NULL, NULL, 0);
+	err = f2fs_get_dnode_of_data(&dn, index, LOOKUP_NODE);
+	if (err)
+		goto put_err;
+	f2fs_put_dnode(&dn);
+
+	if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
+		err = -ENOENT;
+		goto put_err;
+	}
+got_it:
+	if (PageUptodate(page)) {
+		unlock_page(page);
+		return page;
+	}
+
+	/*
+	 * A new dentry page is allocated but not able to be written, since its
+	 * new inode page couldn't be allocated due to -ENOSPC.
+	 * In such the case, its blkaddr can be remained as NEW_ADDR.
+	 * see, f2fs_add_link -> f2fs_get_new_data_page ->
+	 * f2fs_init_inode_metadata.
+	 */
+	if (dn.data_blkaddr == NEW_ADDR) {
+		zero_user_segment(page, 0, PAGE_SIZE);
+		if (!PageUptodate(page))
+			SetPageUptodate(page);
+		unlock_page(page);
+		return page;
+	}
+
+	err = f2fs_submit_page_read(inode, page, dn.data_blkaddr);
+	if (err)
+		goto put_err;
+	return page;
+
+put_err:
+	f2fs_put_page(page, 1);
+	return ERR_PTR(err);
+}
+
+struct page *f2fs_find_data_page(struct inode *inode, pgoff_t index)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct page *page;
+
+	page = find_get_page(mapping, index);
+	if (page && PageUptodate(page))
+		return page;
+	f2fs_put_page(page, 0);
+
+	page = f2fs_get_read_data_page(inode, index, 0, false);
+	if (IS_ERR(page))
+		return page;
+
+	if (PageUptodate(page))
+		return page;
+
+	wait_on_page_locked(page);
+	if (unlikely(!PageUptodate(page))) {
+		f2fs_put_page(page, 0);
+		return ERR_PTR(-EIO);
+	}
+	return page;
+}
+
+/*
+ * If it tries to access a hole, return an error.
+ * Because, the callers, functions in dir.c and GC, should be able to know
+ * whether this page exists or not.
+ */
+struct page *f2fs_get_lock_data_page(struct inode *inode, pgoff_t index,
+							bool for_write)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct page *page;
+repeat:
+	page = f2fs_get_read_data_page(inode, index, 0, for_write);
+	if (IS_ERR(page))
+		return page;
+
+	/* wait for read completion */
+	lock_page(page);
+	if (unlikely(page->mapping != mapping)) {
+		f2fs_put_page(page, 1);
+		goto repeat;
+	}
+	if (unlikely(!PageUptodate(page))) {
+		f2fs_put_page(page, 1);
+		return ERR_PTR(-EIO);
+	}
+	return page;
+}
+
+/*
+ * Caller ensures that this data page is never allocated.
+ * A new zero-filled data page is allocated in the page cache.
+ *
+ * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
+ * f2fs_unlock_op().
+ * Note that, ipage is set only by make_empty_dir, and if any error occur,
+ * ipage should be released by this function.
+ */
+struct page *f2fs_get_new_data_page(struct inode *inode,
+		struct page *ipage, pgoff_t index, bool new_i_size)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct page *page;
+	struct dnode_of_data dn;
+	int err;
+
+	page = f2fs_grab_cache_page(mapping, index, true);
+	if (!page) {
+		/*
+		 * before exiting, we should make sure ipage will be released
+		 * if any error occur.
+		 */
+		f2fs_put_page(ipage, 1);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	set_new_dnode(&dn, inode, ipage, NULL, 0);
+	err = f2fs_reserve_block(&dn, index);
+	if (err) {
+		f2fs_put_page(page, 1);
+		return ERR_PTR(err);
+	}
+	if (!ipage)
+		f2fs_put_dnode(&dn);
+
+	if (PageUptodate(page))
+		goto got_it;
+
+	if (dn.data_blkaddr == NEW_ADDR) {
+		zero_user_segment(page, 0, PAGE_SIZE);
+		if (!PageUptodate(page))
+			SetPageUptodate(page);
+	} else {
+		f2fs_put_page(page, 1);
+
+		/* if ipage exists, blkaddr should be NEW_ADDR */
+		f2fs_bug_on(F2FS_I_SB(inode), ipage);
+		page = f2fs_get_lock_data_page(inode, index, true);
+		if (IS_ERR(page))
+			return page;
+	}
+got_it:
+	if (new_i_size && i_size_read(inode) <
+				((loff_t)(index + 1) << PAGE_SHIFT))
+		f2fs_i_size_write(inode, ((loff_t)(index + 1) << PAGE_SHIFT));
+	return page;
+}
+
+static int __allocate_data_block(struct dnode_of_data *dn, int seg_type)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
+	struct f2fs_summary sum;
+	struct node_info ni;
+	block_t old_blkaddr;
+	blkcnt_t count = 1;
+	int err;
+
+	if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
+		return -EPERM;
+
+	err = f2fs_get_node_info(sbi, dn->nid, &ni);
+	if (err)
+		return err;
+
+	dn->data_blkaddr = datablock_addr(dn->inode,
+				dn->node_page, dn->ofs_in_node);
+	if (dn->data_blkaddr == NEW_ADDR)
+		goto alloc;
+
+	if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
+		return err;
+
+alloc:
+	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
+	old_blkaddr = dn->data_blkaddr;
+	f2fs_allocate_data_block(sbi, NULL, old_blkaddr, &dn->data_blkaddr,
+					&sum, seg_type, NULL, false);
+	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
+		invalidate_mapping_pages(META_MAPPING(sbi),
+					old_blkaddr, old_blkaddr);
+	f2fs_set_data_blkaddr(dn);
+
+	/*
+	 * i_size will be updated by direct_IO. Otherwise, we'll get stale
+	 * data from unwritten block via dio_read.
+	 */
+	return 0;
+}
+
+int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
+{
+	struct inode *inode = file_inode(iocb->ki_filp);
+	struct f2fs_map_blocks map;
+	int flag;
+	int err = 0;
+	bool direct_io = iocb->ki_flags & IOCB_DIRECT;
+
+	/* convert inline data for Direct I/O*/
+	if (direct_io) {
+		err = f2fs_convert_inline_inode(inode);
+		if (err)
+			return err;
+	}
+
+	if (is_inode_flag_set(inode, FI_NO_PREALLOC))
+		return 0;
+
+	map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos);
+	map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from));
+	if (map.m_len > map.m_lblk)
+		map.m_len -= map.m_lblk;
+	else
+		map.m_len = 0;
+
+	map.m_next_pgofs = NULL;
+	map.m_next_extent = NULL;
+	map.m_seg_type = NO_CHECK_TYPE;
+
+	if (direct_io) {
+		map.m_seg_type = f2fs_rw_hint_to_seg_type(iocb->ki_hint);
+		flag = f2fs_force_buffered_io(inode, WRITE) ?
+					F2FS_GET_BLOCK_PRE_AIO :
+					F2FS_GET_BLOCK_PRE_DIO;
+		goto map_blocks;
+	}
+	if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA(inode)) {
+		err = f2fs_convert_inline_inode(inode);
+		if (err)
+			return err;
+	}
+	if (f2fs_has_inline_data(inode))
+		return err;
+
+	flag = F2FS_GET_BLOCK_PRE_AIO;
+
+map_blocks:
+	err = f2fs_map_blocks(inode, &map, 1, flag);
+	if (map.m_len > 0 && err == -ENOSPC) {
+		if (!direct_io)
+			set_inode_flag(inode, FI_NO_PREALLOC);
+		err = 0;
+	}
+	return err;
+}
+
+static inline void __do_map_lock(struct f2fs_sb_info *sbi, int flag, bool lock)
+{
+	if (flag == F2FS_GET_BLOCK_PRE_AIO) {
+		if (lock)
+			down_read(&sbi->node_change);
+		else
+			up_read(&sbi->node_change);
+	} else {
+		if (lock)
+			f2fs_lock_op(sbi);
+		else
+			f2fs_unlock_op(sbi);
+	}
+}
+
+/*
+ * f2fs_map_blocks() now supported readahead/bmap/rw direct_IO with
+ * f2fs_map_blocks structure.
+ * If original data blocks are allocated, then give them to blockdev.
+ * Otherwise,
+ *     a. preallocate requested block addresses
+ *     b. do not use extent cache for better performance
+ *     c. give the block addresses to blockdev
+ */
+int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
+						int create, int flag)
+{
+	unsigned int maxblocks = map->m_len;
+	struct dnode_of_data dn;
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	int mode = create ? ALLOC_NODE : LOOKUP_NODE;
+	pgoff_t pgofs, end_offset, end;
+	int err = 0, ofs = 1;
+	unsigned int ofs_in_node, last_ofs_in_node;
+	blkcnt_t prealloc;
+	struct extent_info ei = {0,0,0};
+	block_t blkaddr;
+	unsigned int start_pgofs;
+
+	if (!maxblocks)
+		return 0;
+
+	map->m_len = 0;
+	map->m_flags = 0;
+
+	/* it only supports block size == page size */
+	pgofs =	(pgoff_t)map->m_lblk;
+	end = pgofs + maxblocks;
+
+	if (!create && f2fs_lookup_extent_cache(inode, pgofs, &ei)) {
+		map->m_pblk = ei.blk + pgofs - ei.fofs;
+		map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs);
+		map->m_flags = F2FS_MAP_MAPPED;
+		if (map->m_next_extent)
+			*map->m_next_extent = pgofs + map->m_len;
+		goto out;
+	}
+
+next_dnode:
+	if (create)
+		__do_map_lock(sbi, flag, true);
+
+	/* When reading holes, we need its node page */
+	set_new_dnode(&dn, inode, NULL, NULL, 0);
+	err = f2fs_get_dnode_of_data(&dn, pgofs, mode);
+	if (err) {
+		if (flag == F2FS_GET_BLOCK_BMAP)
+			map->m_pblk = 0;
+		if (err == -ENOENT) {
+			err = 0;
+			if (map->m_next_pgofs)
+				*map->m_next_pgofs =
+					f2fs_get_next_page_offset(&dn, pgofs);
+			if (map->m_next_extent)
+				*map->m_next_extent =
+					f2fs_get_next_page_offset(&dn, pgofs);
+		}
+		goto unlock_out;
+	}
+
+	start_pgofs = pgofs;
+	prealloc = 0;
+	last_ofs_in_node = ofs_in_node = dn.ofs_in_node;
+	end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
+
+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)) {
+		err = -EFSCORRUPTED;
+		goto sync_out;
+	}
+
+	if (!is_valid_data_blkaddr(sbi, blkaddr)) {
+		if (create) {
+			if (unlikely(f2fs_cp_error(sbi))) {
+				err = -EIO;
+				goto sync_out;
+			}
+			if (flag == F2FS_GET_BLOCK_PRE_AIO) {
+				if (blkaddr == NULL_ADDR) {
+					prealloc++;
+					last_ofs_in_node = dn.ofs_in_node;
+				}
+			} else {
+				WARN_ON(flag != F2FS_GET_BLOCK_PRE_DIO &&
+					flag != F2FS_GET_BLOCK_DIO);
+				err = __allocate_data_block(&dn,
+							map->m_seg_type);
+				if (!err)
+					set_inode_flag(inode, FI_APPEND_WRITE);
+			}
+			if (err)
+				goto sync_out;
+			map->m_flags |= F2FS_MAP_NEW;
+			blkaddr = dn.data_blkaddr;
+		} else {
+			if (flag == F2FS_GET_BLOCK_BMAP) {
+				map->m_pblk = 0;
+				goto sync_out;
+			}
+			if (flag == F2FS_GET_BLOCK_PRECACHE)
+				goto sync_out;
+			if (flag == F2FS_GET_BLOCK_FIEMAP &&
+						blkaddr == NULL_ADDR) {
+				if (map->m_next_pgofs)
+					*map->m_next_pgofs = pgofs + 1;
+				goto sync_out;
+			}
+			if (flag != F2FS_GET_BLOCK_FIEMAP) {
+				/* for defragment case */
+				if (map->m_next_pgofs)
+					*map->m_next_pgofs = pgofs + 1;
+				goto sync_out;
+			}
+		}
+	}
+
+	if (flag == F2FS_GET_BLOCK_PRE_AIO)
+		goto skip;
+
+	if (map->m_len == 0) {
+		/* preallocated unwritten block should be mapped for fiemap. */
+		if (blkaddr == NEW_ADDR)
+			map->m_flags |= F2FS_MAP_UNWRITTEN;
+		map->m_flags |= F2FS_MAP_MAPPED;
+
+		map->m_pblk = blkaddr;
+		map->m_len = 1;
+	} else if ((map->m_pblk != NEW_ADDR &&
+			blkaddr == (map->m_pblk + ofs)) ||
+			(map->m_pblk == NEW_ADDR && blkaddr == NEW_ADDR) ||
+			flag == F2FS_GET_BLOCK_PRE_DIO) {
+		ofs++;
+		map->m_len++;
+	} else {
+		goto sync_out;
+	}
+
+skip:
+	dn.ofs_in_node++;
+	pgofs++;
+
+	/* preallocate blocks in batch for one dnode page */
+	if (flag == F2FS_GET_BLOCK_PRE_AIO &&
+			(pgofs == end || dn.ofs_in_node == end_offset)) {
+
+		dn.ofs_in_node = ofs_in_node;
+		err = f2fs_reserve_new_blocks(&dn, prealloc);
+		if (err)
+			goto sync_out;
+
+		map->m_len += dn.ofs_in_node - ofs_in_node;
+		if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) {
+			err = -ENOSPC;
+			goto sync_out;
+		}
+		dn.ofs_in_node = end_offset;
+	}
+
+	if (pgofs >= end)
+		goto sync_out;
+	else if (dn.ofs_in_node < end_offset)
+		goto next_block;
+
+	if (flag == F2FS_GET_BLOCK_PRECACHE) {
+		if (map->m_flags & F2FS_MAP_MAPPED) {
+			unsigned int ofs = start_pgofs - map->m_lblk;
+
+			f2fs_update_extent_cache_range(&dn,
+				start_pgofs, map->m_pblk + ofs,
+				map->m_len - ofs);
+		}
+	}
+
+	f2fs_put_dnode(&dn);
+
+	if (create) {
+		__do_map_lock(sbi, flag, false);
+		f2fs_balance_fs(sbi, dn.node_changed);
+	}
+	goto next_dnode;
+
+sync_out:
+	if (flag == F2FS_GET_BLOCK_PRECACHE) {
+		if (map->m_flags & F2FS_MAP_MAPPED) {
+			unsigned int ofs = start_pgofs - map->m_lblk;
+
+			f2fs_update_extent_cache_range(&dn,
+				start_pgofs, map->m_pblk + ofs,
+				map->m_len - ofs);
+		}
+		if (map->m_next_extent)
+			*map->m_next_extent = pgofs + 1;
+	}
+	f2fs_put_dnode(&dn);
+unlock_out:
+	if (create) {
+		__do_map_lock(sbi, flag, false);
+		f2fs_balance_fs(sbi, dn.node_changed);
+	}
+out:
+	trace_f2fs_map_blocks(inode, map, err);
+	return err;
+}
+
+bool f2fs_overwrite_io(struct inode *inode, loff_t pos, size_t len)
+{
+	struct f2fs_map_blocks map;
+	block_t last_lblk;
+	int err;
+
+	if (pos + len > i_size_read(inode))
+		return false;
+
+	map.m_lblk = F2FS_BYTES_TO_BLK(pos);
+	map.m_next_pgofs = NULL;
+	map.m_next_extent = NULL;
+	map.m_seg_type = NO_CHECK_TYPE;
+	last_lblk = F2FS_BLK_ALIGN(pos + len);
+
+	while (map.m_lblk < last_lblk) {
+		map.m_len = last_lblk - map.m_lblk;
+		err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DEFAULT);
+		if (err || map.m_len == 0)
+			return false;
+		map.m_lblk += map.m_len;
+	}
+	return true;
+}
+
+static int __get_data_block(struct inode *inode, sector_t iblock,
+			struct buffer_head *bh, int create, int flag,
+			pgoff_t *next_pgofs, int seg_type)
+{
+	struct f2fs_map_blocks map;
+	int err;
+
+	map.m_lblk = iblock;
+	map.m_len = bh->b_size >> inode->i_blkbits;
+	map.m_next_pgofs = next_pgofs;
+	map.m_next_extent = NULL;
+	map.m_seg_type = seg_type;
+
+	err = f2fs_map_blocks(inode, &map, create, flag);
+	if (!err) {
+		map_bh(bh, inode->i_sb, map.m_pblk);
+		bh->b_state = (bh->b_state & ~F2FS_MAP_FLAGS) | map.m_flags;
+		bh->b_size = (u64)map.m_len << inode->i_blkbits;
+	}
+	return err;
+}
+
+static int get_data_block(struct inode *inode, sector_t iblock,
+			struct buffer_head *bh_result, int create, int flag,
+			pgoff_t *next_pgofs)
+{
+	return __get_data_block(inode, iblock, bh_result, create,
+							flag, next_pgofs,
+							NO_CHECK_TYPE);
+}
+
+static int get_data_block_dio(struct inode *inode, sector_t iblock,
+			struct buffer_head *bh_result, int create)
+{
+	return __get_data_block(inode, iblock, bh_result, create,
+						F2FS_GET_BLOCK_DIO, NULL,
+						f2fs_rw_hint_to_seg_type(
+							inode->i_write_hint));
+}
+
+static int get_data_block_bmap(struct inode *inode, sector_t iblock,
+			struct buffer_head *bh_result, int create)
+{
+	/* Block number less than F2FS MAX BLOCKS */
+	if (unlikely(iblock >= F2FS_I_SB(inode)->max_file_blocks))
+		return -EFBIG;
+
+	return __get_data_block(inode, iblock, bh_result, create,
+						F2FS_GET_BLOCK_BMAP, NULL,
+						NO_CHECK_TYPE);
+}
+
+static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
+{
+	return (offset >> inode->i_blkbits);
+}
+
+static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
+{
+	return (blk << inode->i_blkbits);
+}
+
+static int f2fs_xattr_fiemap(struct inode *inode,
+				struct fiemap_extent_info *fieinfo)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct page *page;
+	struct node_info ni;
+	__u64 phys = 0, len;
+	__u32 flags;
+	nid_t xnid = F2FS_I(inode)->i_xattr_nid;
+	int err = 0;
+
+	if (f2fs_has_inline_xattr(inode)) {
+		int offset;
+
+		page = f2fs_grab_cache_page(NODE_MAPPING(sbi),
+						inode->i_ino, false);
+		if (!page)
+			return -ENOMEM;
+
+		err = f2fs_get_node_info(sbi, inode->i_ino, &ni);
+		if (err) {
+			f2fs_put_page(page, 1);
+			return err;
+		}
+
+		phys = (__u64)blk_to_logical(inode, ni.blk_addr);
+		offset = offsetof(struct f2fs_inode, i_addr) +
+					sizeof(__le32) * (DEF_ADDRS_PER_INODE -
+					get_inline_xattr_addrs(inode));
+
+		phys += offset;
+		len = inline_xattr_size(inode);
+
+		f2fs_put_page(page, 1);
+
+		flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_NOT_ALIGNED;
+
+		if (!xnid)
+			flags |= FIEMAP_EXTENT_LAST;
+
+		err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
+		if (err || err == 1)
+			return err;
+	}
+
+	if (xnid) {
+		page = f2fs_grab_cache_page(NODE_MAPPING(sbi), xnid, false);
+		if (!page)
+			return -ENOMEM;
+
+		err = f2fs_get_node_info(sbi, xnid, &ni);
+		if (err) {
+			f2fs_put_page(page, 1);
+			return err;
+		}
+
+		phys = (__u64)blk_to_logical(inode, ni.blk_addr);
+		len = inode->i_sb->s_blocksize;
+
+		f2fs_put_page(page, 1);
+
+		flags = FIEMAP_EXTENT_LAST;
+	}
+
+	if (phys)
+		err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
+
+	return (err < 0 ? err : 0);
+}
+
+int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
+		u64 start, u64 len)
+{
+	struct buffer_head map_bh;
+	sector_t start_blk, last_blk;
+	pgoff_t next_pgofs;
+	u64 logical = 0, phys = 0, size = 0;
+	u32 flags = 0;
+	int ret = 0;
+
+	if (fieinfo->fi_flags & FIEMAP_FLAG_CACHE) {
+		ret = f2fs_precache_extents(inode);
+		if (ret)
+			return ret;
+	}
+
+	ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR);
+	if (ret)
+		return ret;
+
+	inode_lock(inode);
+
+	if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
+		ret = f2fs_xattr_fiemap(inode, fieinfo);
+		goto out;
+	}
+
+	if (f2fs_has_inline_data(inode)) {
+		ret = f2fs_inline_data_fiemap(inode, fieinfo, start, len);
+		if (ret != -EAGAIN)
+			goto out;
+	}
+
+	if (logical_to_blk(inode, len) == 0)
+		len = blk_to_logical(inode, 1);
+
+	start_blk = logical_to_blk(inode, start);
+	last_blk = logical_to_blk(inode, start + len - 1);
+
+next:
+	memset(&map_bh, 0, sizeof(struct buffer_head));
+	map_bh.b_size = len;
+
+	ret = get_data_block(inode, start_blk, &map_bh, 0,
+					F2FS_GET_BLOCK_FIEMAP, &next_pgofs);
+	if (ret)
+		goto out;
+
+	/* HOLE */
+	if (!buffer_mapped(&map_bh)) {
+		start_blk = next_pgofs;
+
+		if (blk_to_logical(inode, start_blk) < blk_to_logical(inode,
+					F2FS_I_SB(inode)->max_file_blocks))
+			goto prep_next;
+
+		flags |= FIEMAP_EXTENT_LAST;
+	}
+
+	if (size) {
+		if (f2fs_encrypted_inode(inode))
+			flags |= FIEMAP_EXTENT_DATA_ENCRYPTED;
+
+		ret = fiemap_fill_next_extent(fieinfo, logical,
+				phys, size, flags);
+	}
+
+	if (start_blk > last_blk || ret)
+		goto out;
+
+	logical = blk_to_logical(inode, start_blk);
+	phys = blk_to_logical(inode, map_bh.b_blocknr);
+	size = map_bh.b_size;
+	flags = 0;
+	if (buffer_unwritten(&map_bh))
+		flags = FIEMAP_EXTENT_UNWRITTEN;
+
+	start_blk += logical_to_blk(inode, size);
+
+prep_next:
+	cond_resched();
+	if (fatal_signal_pending(current))
+		ret = -EINTR;
+	else
+		goto next;
+out:
+	if (ret == 1)
+		ret = 0;
+
+	inode_unlock(inode);
+	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.
+ *
+ * Note that the aops->readpages() function is ONLY used for read-ahead. If
+ * this function ever deviates from doing just read-ahead, it should either
+ * use ->readpage() or do the necessary surgery to decouple ->readpages()
+ * from read-ahead.
+ */
+static int f2fs_mpage_readpages(struct address_space *mapping,
+			struct list_head *pages, struct page *page,
+			unsigned nr_pages, bool is_readahead)
+{
+	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;
+
+	map.m_pblk = 0;
+	map.m_lblk = 0;
+	map.m_len = 0;
+	map.m_flags = 0;
+	map.m_next_pgofs = NULL;
+	map.m_next_extent = NULL;
+	map.m_seg_type = NO_CHECK_TYPE;
+
+	for (; nr_pages; nr_pages--) {
+		if (pages) {
+			page = list_last_entry(pages, struct page, lru);
+
+			prefetchw(&page->flags);
+			list_del(&page->lru);
+			if (add_to_page_cache_lru(page, mapping,
+						  page->index,
+						  readahead_gfp_mask(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;
+
+		/*
+		 * 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_flags = 0;
+
+		if (block_in_file < last_block) {
+			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_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;
+
+		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);
+	}
+	BUG_ON(pages && !list_empty(pages));
+	if (bio)
+		__submit_bio(F2FS_I_SB(inode), bio, DATA);
+	return 0;
+}
+
+static int f2fs_read_data_page(struct file *file, struct page *page)
+{
+	struct inode *inode = page->mapping->host;
+	int ret = -EAGAIN;
+
+	trace_f2fs_readpage(page, DATA);
+
+	/* If the file has inline data, try to read it directly */
+	if (f2fs_has_inline_data(inode))
+		ret = f2fs_read_inline_data(inode, page);
+	if (ret == -EAGAIN)
+		ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1, false);
+	return ret;
+}
+
+static int f2fs_read_data_pages(struct file *file,
+			struct address_space *mapping,
+			struct list_head *pages, unsigned nr_pages)
+{
+	struct inode *inode = mapping->host;
+	struct page *page = list_last_entry(pages, struct page, lru);
+
+	trace_f2fs_readpages(inode, page, nr_pages);
+
+	/* If the file has inline data, skip readpages */
+	if (f2fs_has_inline_data(inode))
+		return 0;
+
+	return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages, true);
+}
+
+static int encrypt_one_page(struct f2fs_io_info *fio)
+{
+	struct inode *inode = fio->page->mapping->host;
+	struct page *mpage;
+	gfp_t gfp_flags = GFP_NOFS;
+
+	if (!f2fs_encrypted_file(inode))
+		return 0;
+
+	/* wait for GCed page writeback via META_MAPPING */
+	f2fs_wait_on_block_writeback(inode, fio->old_blkaddr);
+
+retry_encrypt:
+	fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page,
+			PAGE_SIZE, 0, fio->page->index, gfp_flags);
+	if (IS_ERR(fio->encrypted_page)) {
+		/* flush pending IOs and wait for a while in the ENOMEM case */
+		if (PTR_ERR(fio->encrypted_page) == -ENOMEM) {
+			f2fs_flush_merged_writes(fio->sbi);
+			congestion_wait(BLK_RW_ASYNC, HZ/50);
+			gfp_flags |= __GFP_NOFAIL;
+			goto retry_encrypt;
+		}
+		return PTR_ERR(fio->encrypted_page);
+	}
+
+	mpage = find_lock_page(META_MAPPING(fio->sbi), fio->old_blkaddr);
+	if (mpage) {
+		if (PageUptodate(mpage))
+			memcpy(page_address(mpage),
+				page_address(fio->encrypted_page), PAGE_SIZE);
+		f2fs_put_page(mpage, 1);
+	}
+	return 0;
+}
+
+static inline bool check_inplace_update_policy(struct inode *inode,
+				struct f2fs_io_info *fio)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	unsigned int policy = SM_I(sbi)->ipu_policy;
+
+	if (policy & (0x1 << F2FS_IPU_FORCE))
+		return true;
+	if (policy & (0x1 << F2FS_IPU_SSR) && f2fs_need_SSR(sbi))
+		return true;
+	if (policy & (0x1 << F2FS_IPU_UTIL) &&
+			utilization(sbi) > SM_I(sbi)->min_ipu_util)
+		return true;
+	if (policy & (0x1 << F2FS_IPU_SSR_UTIL) && f2fs_need_SSR(sbi) &&
+			utilization(sbi) > SM_I(sbi)->min_ipu_util)
+		return true;
+
+	/*
+	 * IPU for rewrite async pages
+	 */
+	if (policy & (0x1 << F2FS_IPU_ASYNC) &&
+			fio && fio->op == REQ_OP_WRITE &&
+			!(fio->op_flags & REQ_SYNC) &&
+			!f2fs_encrypted_inode(inode))
+		return true;
+
+	/* this is only set during fdatasync */
+	if (policy & (0x1 << F2FS_IPU_FSYNC) &&
+			is_inode_flag_set(inode, FI_NEED_IPU))
+		return true;
+
+	return false;
+}
+
+bool f2fs_should_update_inplace(struct inode *inode, struct f2fs_io_info *fio)
+{
+	if (f2fs_is_pinned_file(inode))
+		return true;
+
+	/* if this is cold file, we should overwrite to avoid fragmentation */
+	if (file_is_cold(inode))
+		return true;
+
+	return check_inplace_update_policy(inode, fio);
+}
+
+bool f2fs_should_update_outplace(struct inode *inode, struct f2fs_io_info *fio)
+{
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+
+	if (test_opt(sbi, LFS))
+		return true;
+	if (S_ISDIR(inode->i_mode))
+		return true;
+	if (f2fs_is_atomic_file(inode))
+		return true;
+	if (fio) {
+		if (is_cold_data(fio->page))
+			return true;
+		if (IS_ATOMIC_WRITTEN_PAGE(fio->page))
+			return true;
+	}
+	return false;
+}
+
+static inline bool need_inplace_update(struct f2fs_io_info *fio)
+{
+	struct inode *inode = fio->page->mapping->host;
+
+	if (f2fs_should_update_outplace(inode, fio))
+		return false;
+
+	return f2fs_should_update_inplace(inode, fio);
+}
+
+int f2fs_do_write_data_page(struct f2fs_io_info *fio)
+{
+	struct page *page = fio->page;
+	struct inode *inode = page->mapping->host;
+	struct dnode_of_data dn;
+	struct extent_info ei = {0,0,0};
+	struct node_info ni;
+	bool ipu_force = false;
+	int err = 0;
+
+	set_new_dnode(&dn, inode, NULL, NULL, 0);
+	if (need_inplace_update(fio) &&
+			f2fs_lookup_extent_cache(inode, page->index, &ei)) {
+		fio->old_blkaddr = ei.blk + page->index - ei.fofs;
+
+		if (!f2fs_is_valid_blkaddr(fio->sbi, fio->old_blkaddr,
+							DATA_GENERIC))
+			return -EFSCORRUPTED;
+
+		ipu_force = true;
+		fio->need_lock = LOCK_DONE;
+		goto got_it;
+	}
+
+	/* Deadlock due to between page->lock and f2fs_lock_op */
+	if (fio->need_lock == LOCK_REQ && !f2fs_trylock_op(fio->sbi))
+		return -EAGAIN;
+
+	err = f2fs_get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
+	if (err)
+		goto out;
+
+	fio->old_blkaddr = dn.data_blkaddr;
+
+	/* This page is already truncated */
+	if (fio->old_blkaddr == NULL_ADDR) {
+		ClearPageUptodate(page);
+		clear_cold_data(page);
+		goto out_writepage;
+	}
+got_it:
+	if (__is_valid_data_blkaddr(fio->old_blkaddr) &&
+		!f2fs_is_valid_blkaddr(fio->sbi, fio->old_blkaddr,
+							DATA_GENERIC)) {
+		err = -EFSCORRUPTED;
+		goto out_writepage;
+	}
+	/*
+	 * 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) &&
+					need_inplace_update(fio))) {
+		err = encrypt_one_page(fio);
+		if (err)
+			goto out_writepage;
+
+		set_page_writeback(page);
+		ClearPageError(page);
+		f2fs_put_dnode(&dn);
+		if (fio->need_lock == LOCK_REQ)
+			f2fs_unlock_op(fio->sbi);
+		err = f2fs_inplace_write_data(fio);
+		trace_f2fs_do_write_data_page(fio->page, IPU);
+		set_inode_flag(inode, FI_UPDATE_WRITE);
+		return err;
+	}
+
+	if (fio->need_lock == LOCK_RETRY) {
+		if (!f2fs_trylock_op(fio->sbi)) {
+			err = -EAGAIN;
+			goto out_writepage;
+		}
+		fio->need_lock = LOCK_REQ;
+	}
+
+	err = f2fs_get_node_info(fio->sbi, dn.nid, &ni);
+	if (err)
+		goto out_writepage;
+
+	fio->version = ni.version;
+
+	err = encrypt_one_page(fio);
+	if (err)
+		goto out_writepage;
+
+	set_page_writeback(page);
+	ClearPageError(page);
+
+	/* LFS mode write path */
+	f2fs_outplace_write_data(&dn, fio);
+	trace_f2fs_do_write_data_page(page, OPU);
+	set_inode_flag(inode, FI_APPEND_WRITE);
+	if (page->index == 0)
+		set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
+out_writepage:
+	f2fs_put_dnode(&dn);
+out:
+	if (fio->need_lock == LOCK_REQ)
+		f2fs_unlock_op(fio->sbi);
+	return err;
+}
+
+static int __write_data_page(struct page *page, bool *submitted,
+				struct writeback_control *wbc,
+				enum iostat_type io_type)
+{
+	struct inode *inode = page->mapping->host;
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	loff_t i_size = i_size_read(inode);
+	const pgoff_t end_index = ((unsigned long long) i_size)
+							>> PAGE_SHIFT;
+	loff_t psize = (loff_t)(page->index + 1) << PAGE_SHIFT;
+	unsigned offset = 0;
+	bool need_balance_fs = false;
+	int err = 0;
+	struct f2fs_io_info fio = {
+		.sbi = sbi,
+		.ino = inode->i_ino,
+		.type = DATA,
+		.op = REQ_OP_WRITE,
+		.op_flags = wbc_to_write_flags(wbc),
+		.old_blkaddr = NULL_ADDR,
+		.page = page,
+		.encrypted_page = NULL,
+		.submitted = false,
+		.need_lock = LOCK_RETRY,
+		.io_type = io_type,
+		.io_wbc = wbc,
+	};
+
+	trace_f2fs_writepage(page, DATA);
+
+	/* we should bypass data pages to proceed the kworkder jobs */
+	if (unlikely(f2fs_cp_error(sbi))) {
+		mapping_set_error(page->mapping, -EIO);
+		/*
+		 * don't drop any dirty dentry pages for keeping lastest
+		 * directory structure.
+		 */
+		if (S_ISDIR(inode->i_mode))
+			goto redirty_out;
+		goto out;
+	}
+
+	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
+		goto redirty_out;
+
+	if (page->index < end_index)
+		goto write;
+
+	/*
+	 * If the offset is out-of-range of file size,
+	 * this page does not have to be written to disk.
+	 */
+	offset = i_size & (PAGE_SIZE - 1);
+	if ((page->index >= end_index + 1) || !offset)
+		goto out;
+
+	zero_user_segment(page, offset, PAGE_SIZE);
+write:
+	if (f2fs_is_drop_cache(inode))
+		goto out;
+	/* we should not write 0'th page having journal header */
+	if (f2fs_is_volatile_file(inode) && (!page->index ||
+			(!wbc->for_reclaim &&
+			f2fs_available_free_memory(sbi, BASE_CHECK))))
+		goto redirty_out;
+
+	/* Dentry blocks are controlled by checkpoint */
+	if (S_ISDIR(inode->i_mode)) {
+		fio.need_lock = LOCK_DONE;
+		err = f2fs_do_write_data_page(&fio);
+		goto done;
+	}
+
+	if (!wbc->for_reclaim)
+		need_balance_fs = true;
+	else if (has_not_enough_free_secs(sbi, 0, 0))
+		goto redirty_out;
+	else
+		set_inode_flag(inode, FI_HOT_DATA);
+
+	err = -EAGAIN;
+	if (f2fs_has_inline_data(inode)) {
+		err = f2fs_write_inline_data(inode, page);
+		if (!err)
+			goto out;
+	}
+
+	if (err == -EAGAIN) {
+		err = f2fs_do_write_data_page(&fio);
+		if (err == -EAGAIN) {
+			fio.need_lock = LOCK_REQ;
+			err = f2fs_do_write_data_page(&fio);
+		}
+	}
+
+	if (err) {
+		file_set_keep_isize(inode);
+	} else {
+		down_write(&F2FS_I(inode)->i_sem);
+		if (F2FS_I(inode)->last_disk_size < psize)
+			F2FS_I(inode)->last_disk_size = psize;
+		up_write(&F2FS_I(inode)->i_sem);
+	}
+
+done:
+	if (err && err != -ENOENT)
+		goto redirty_out;
+
+out:
+	inode_dec_dirty_pages(inode);
+	if (err) {
+		ClearPageUptodate(page);
+		clear_cold_data(page);
+	}
+
+	if (wbc->for_reclaim) {
+		f2fs_submit_merged_write_cond(sbi, inode, 0, page->index, DATA);
+		clear_inode_flag(inode, FI_HOT_DATA);
+		f2fs_remove_dirty_inode(inode);
+		submitted = NULL;
+	}
+
+	unlock_page(page);
+	if (!S_ISDIR(inode->i_mode))
+		f2fs_balance_fs(sbi, need_balance_fs);
+
+	if (unlikely(f2fs_cp_error(sbi))) {
+		f2fs_submit_merged_write(sbi, DATA);
+		submitted = NULL;
+	}
+
+	if (submitted)
+		*submitted = fio.submitted;
+
+	return 0;
+
+redirty_out:
+	redirty_page_for_writepage(wbc, page);
+	/*
+	 * pageout() in MM traslates EAGAIN, so calls handle_write_error()
+	 * -> mapping_set_error() -> set_bit(AS_EIO, ...).
+	 * file_write_and_wait_range() will see EIO error, which is critical
+	 * to return value of fsync() followed by atomic_write failure to user.
+	 */
+	if (!err || wbc->for_reclaim)
+		return AOP_WRITEPAGE_ACTIVATE;
+	unlock_page(page);
+	return err;
+}
+
+static int f2fs_write_data_page(struct page *page,
+					struct writeback_control *wbc)
+{
+	return __write_data_page(page, NULL, wbc, FS_DATA_IO);
+}
+
+/*
+ * This function was copied from write_cche_pages from mm/page-writeback.c.
+ * The major change is making write step of cold data page separately from
+ * warm/hot data page.
+ */
+static int f2fs_write_cache_pages(struct address_space *mapping,
+					struct writeback_control *wbc,
+					enum iostat_type io_type)
+{
+	int ret = 0;
+	int done = 0;
+	struct pagevec pvec;
+	struct f2fs_sb_info *sbi = F2FS_M_SB(mapping);
+	int nr_pages;
+	pgoff_t uninitialized_var(writeback_index);
+	pgoff_t index;
+	pgoff_t end;		/* Inclusive */
+	pgoff_t done_index;
+	pgoff_t last_idx = ULONG_MAX;
+	int cycled;
+	int range_whole = 0;
+	int tag;
+
+	pagevec_init(&pvec);
+
+	if (get_dirty_pages(mapping->host) <=
+				SM_I(F2FS_M_SB(mapping))->min_hot_blocks)
+		set_inode_flag(mapping->host, FI_HOT_DATA);
+	else
+		clear_inode_flag(mapping->host, FI_HOT_DATA);
+
+	if (wbc->range_cyclic) {
+		writeback_index = mapping->writeback_index; /* prev offset */
+		index = writeback_index;
+		if (index == 0)
+			cycled = 1;
+		else
+			cycled = 0;
+		end = -1;
+	} else {
+		index = wbc->range_start >> PAGE_SHIFT;
+		end = wbc->range_end >> PAGE_SHIFT;
+		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
+			range_whole = 1;
+		cycled = 1; /* ignore range_cyclic tests */
+	}
+	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
+		tag = PAGECACHE_TAG_TOWRITE;
+	else
+		tag = PAGECACHE_TAG_DIRTY;
+retry:
+	if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
+		tag_pages_for_writeback(mapping, index, end);
+	done_index = index;
+	while (!done && (index <= end)) {
+		int i;
+
+		nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
+				tag);
+		if (nr_pages == 0)
+			break;
+
+		for (i = 0; i < nr_pages; i++) {
+			struct page *page = pvec.pages[i];
+			bool submitted = false;
+
+			/* give a priority to WB_SYNC threads */
+			if (atomic_read(&sbi->wb_sync_req[DATA]) &&
+					wbc->sync_mode == WB_SYNC_NONE) {
+				done = 1;
+				break;
+			}
+
+			done_index = page->index;
+retry_write:
+			lock_page(page);
+
+			if (unlikely(page->mapping != mapping)) {
+continue_unlock:
+				unlock_page(page);
+				continue;
+			}
+
+			if (!PageDirty(page)) {
+				/* someone wrote it for us */
+				goto continue_unlock;
+			}
+
+			if (PageWriteback(page)) {
+				if (wbc->sync_mode != WB_SYNC_NONE)
+					f2fs_wait_on_page_writeback(page,
+								DATA, true);
+				else
+					goto continue_unlock;
+			}
+
+			BUG_ON(PageWriteback(page));
+			if (!clear_page_dirty_for_io(page))
+				goto continue_unlock;
+
+			ret = __write_data_page(page, &submitted, wbc, io_type);
+			if (unlikely(ret)) {
+				/*
+				 * keep nr_to_write, since vfs uses this to
+				 * get # of written pages.
+				 */
+				if (ret == AOP_WRITEPAGE_ACTIVATE) {
+					unlock_page(page);
+					ret = 0;
+					continue;
+				} else if (ret == -EAGAIN) {
+					ret = 0;
+					if (wbc->sync_mode == WB_SYNC_ALL) {
+						cond_resched();
+						congestion_wait(BLK_RW_ASYNC,
+									HZ/50);
+						goto retry_write;
+					}
+					continue;
+				}
+				done_index = page->index + 1;
+				done = 1;
+				break;
+			} else if (submitted) {
+				last_idx = page->index;
+			}
+
+			if (--wbc->nr_to_write <= 0 &&
+					wbc->sync_mode == WB_SYNC_NONE) {
+				done = 1;
+				break;
+			}
+		}
+		pagevec_release(&pvec);
+		cond_resched();
+	}
+
+	if (!cycled && !done) {
+		cycled = 1;
+		index = 0;
+		end = writeback_index - 1;
+		goto retry;
+	}
+	if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
+		mapping->writeback_index = done_index;
+
+	if (last_idx != ULONG_MAX)
+		f2fs_submit_merged_write_cond(F2FS_M_SB(mapping), mapping->host,
+						0, last_idx, DATA);
+
+	return ret;
+}
+
+static inline bool __should_serialize_io(struct inode *inode,
+					struct writeback_control *wbc)
+{
+	if (!S_ISREG(inode->i_mode))
+		return false;
+	if (wbc->sync_mode != WB_SYNC_ALL)
+		return true;
+	if (get_dirty_pages(inode) >= SM_I(F2FS_I_SB(inode))->min_seq_blocks)
+		return true;
+	return false;
+}
+
+static int __f2fs_write_data_pages(struct address_space *mapping,
+						struct writeback_control *wbc,
+						enum iostat_type io_type)
+{
+	struct inode *inode = mapping->host;
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct blk_plug plug;
+	int ret;
+	bool locked = false;
+
+	/* deal with chardevs and other special file */
+	if (!mapping->a_ops->writepage)
+		return 0;
+
+	/* skip writing if there is no dirty page in this inode */
+	if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
+		return 0;
+
+	/* during POR, we don't need to trigger writepage at all. */
+	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
+		goto skip_write;
+
+	if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
+			get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
+			f2fs_available_free_memory(sbi, DIRTY_DENTS))
+		goto skip_write;
+
+	/* skip writing during file defragment */
+	if (is_inode_flag_set(inode, FI_DO_DEFRAG))
+		goto skip_write;
+
+	trace_f2fs_writepages(mapping->host, wbc, DATA);
+
+	/* to avoid spliting IOs due to mixed WB_SYNC_ALL and WB_SYNC_NONE */
+	if (wbc->sync_mode == WB_SYNC_ALL)
+		atomic_inc(&sbi->wb_sync_req[DATA]);
+	else if (atomic_read(&sbi->wb_sync_req[DATA]))
+		goto skip_write;
+
+	if (__should_serialize_io(inode, wbc)) {
+		mutex_lock(&sbi->writepages);
+		locked = true;
+	}
+
+	blk_start_plug(&plug);
+	ret = f2fs_write_cache_pages(mapping, wbc, io_type);
+	blk_finish_plug(&plug);
+
+	if (locked)
+		mutex_unlock(&sbi->writepages);
+
+	if (wbc->sync_mode == WB_SYNC_ALL)
+		atomic_dec(&sbi->wb_sync_req[DATA]);
+	/*
+	 * if some pages were truncated, we cannot guarantee its mapping->host
+	 * to detect pending bios.
+	 */
+
+	f2fs_remove_dirty_inode(inode);
+	return ret;
+
+skip_write:
+	wbc->pages_skipped += get_dirty_pages(inode);
+	trace_f2fs_writepages(mapping->host, wbc, DATA);
+	return 0;
+}
+
+static int f2fs_write_data_pages(struct address_space *mapping,
+			    struct writeback_control *wbc)
+{
+	struct inode *inode = mapping->host;
+
+	return __f2fs_write_data_pages(mapping, wbc,
+			F2FS_I(inode)->cp_task == current ?
+			FS_CP_DATA_IO : FS_DATA_IO);
+}
+
+static void f2fs_write_failed(struct address_space *mapping, loff_t to)
+{
+	struct inode *inode = mapping->host;
+	loff_t i_size = i_size_read(inode);
+
+	if (to > i_size) {
+		down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+		down_write(&F2FS_I(inode)->i_mmap_sem);
+
+		truncate_pagecache(inode, i_size);
+		f2fs_truncate_blocks(inode, i_size, true);
+
+		up_write(&F2FS_I(inode)->i_mmap_sem);
+		up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
+	}
+}
+
+static int prepare_write_begin(struct f2fs_sb_info *sbi,
+			struct page *page, loff_t pos, unsigned len,
+			block_t *blk_addr, bool *node_changed)
+{
+	struct inode *inode = page->mapping->host;
+	pgoff_t index = page->index;
+	struct dnode_of_data dn;
+	struct page *ipage;
+	bool locked = false;
+	struct extent_info ei = {0,0,0};
+	int err = 0;
+	int flag;
+
+	/*
+	 * we already allocated all the blocks, so we don't need to get
+	 * the block addresses when there is no need to fill the page.
+	 */
+	if (!f2fs_has_inline_data(inode) && len == PAGE_SIZE &&
+			!is_inode_flag_set(inode, FI_NO_PREALLOC))
+		return 0;
+
+	/* f2fs_lock_op avoids race between write CP and convert_inline_page */
+	if (f2fs_has_inline_data(inode) && pos + len > MAX_INLINE_DATA(inode))
+		flag = F2FS_GET_BLOCK_DEFAULT;
+	else
+		flag = F2FS_GET_BLOCK_PRE_AIO;
+
+	if (f2fs_has_inline_data(inode) ||
+			(pos & PAGE_MASK) >= i_size_read(inode)) {
+		__do_map_lock(sbi, flag, true);
+		locked = true;
+	}
+restart:
+	/* check inline_data */
+	ipage = f2fs_get_node_page(sbi, inode->i_ino);
+	if (IS_ERR(ipage)) {
+		err = PTR_ERR(ipage);
+		goto unlock_out;
+	}
+
+	set_new_dnode(&dn, inode, ipage, ipage, 0);
+
+	if (f2fs_has_inline_data(inode)) {
+		if (pos + len <= MAX_INLINE_DATA(inode)) {
+			f2fs_do_read_inline_data(page, ipage);
+			set_inode_flag(inode, FI_DATA_EXIST);
+			if (inode->i_nlink)
+				set_inline_node(ipage);
+		} else {
+			err = f2fs_convert_inline_page(&dn, page);
+			if (err)
+				goto out;
+			if (dn.data_blkaddr == NULL_ADDR)
+				err = f2fs_get_block(&dn, index);
+		}
+	} else if (locked) {
+		err = f2fs_get_block(&dn, index);
+	} else {
+		if (f2fs_lookup_extent_cache(inode, index, &ei)) {
+			dn.data_blkaddr = ei.blk + index - ei.fofs;
+		} else {
+			/* hole case */
+			err = f2fs_get_dnode_of_data(&dn, index, LOOKUP_NODE);
+			if (err || dn.data_blkaddr == NULL_ADDR) {
+				f2fs_put_dnode(&dn);
+				__do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO,
+								true);
+				WARN_ON(flag != F2FS_GET_BLOCK_PRE_AIO);
+				locked = true;
+				goto restart;
+			}
+		}
+	}
+
+	/* convert_inline_page can make node_changed */
+	*blk_addr = dn.data_blkaddr;
+	*node_changed = dn.node_changed;
+out:
+	f2fs_put_dnode(&dn);
+unlock_out:
+	if (locked)
+		__do_map_lock(sbi, flag, false);
+	return err;
+}
+
+static int f2fs_write_begin(struct file *file, struct address_space *mapping,
+		loff_t pos, unsigned len, unsigned flags,
+		struct page **pagep, void **fsdata)
+{
+	struct inode *inode = mapping->host;
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct page *page = NULL;
+	pgoff_t index = ((unsigned long long) pos) >> PAGE_SHIFT;
+	bool need_balance = false, drop_atomic = false;
+	block_t blkaddr = NULL_ADDR;
+	int err = 0;
+
+	trace_f2fs_write_begin(inode, pos, len, flags);
+
+	if ((f2fs_is_atomic_file(inode) &&
+			!f2fs_available_free_memory(sbi, INMEM_PAGES)) ||
+			is_inode_flag_set(inode, FI_ATOMIC_REVOKE_REQUEST)) {
+		err = -ENOMEM;
+		drop_atomic = true;
+		goto fail;
+	}
+
+	/*
+	 * We should check this at this moment to avoid deadlock on inode page
+	 * and #0 page. The locking rule for inline_data conversion should be:
+	 * lock_page(page #0) -> lock_page(inode_page)
+	 */
+	if (index != 0) {
+		err = f2fs_convert_inline_inode(inode);
+		if (err)
+			goto fail;
+	}
+repeat:
+	/*
+	 * Do not use grab_cache_page_write_begin() to avoid deadlock due to
+	 * wait_for_stable_page. Will wait that below with our IO control.
+	 */
+	page = f2fs_pagecache_get_page(mapping, index,
+				FGP_LOCK | FGP_WRITE | FGP_CREAT, GFP_NOFS);
+	if (!page) {
+		err = -ENOMEM;
+		goto fail;
+	}
+
+	*pagep = page;
+
+	err = prepare_write_begin(sbi, page, pos, len,
+					&blkaddr, &need_balance);
+	if (err)
+		goto fail;
+
+	if (need_balance && has_not_enough_free_secs(sbi, 0, 0)) {
+		unlock_page(page);
+		f2fs_balance_fs(sbi, true);
+		lock_page(page);
+		if (page->mapping != mapping) {
+			/* The page got truncated from under us */
+			f2fs_put_page(page, 1);
+			goto repeat;
+		}
+	}
+
+	f2fs_wait_on_page_writeback(page, DATA, false);
+
+	if (len == PAGE_SIZE || PageUptodate(page))
+		return 0;
+
+	if (!(pos & (PAGE_SIZE - 1)) && (pos + len) >= i_size_read(inode)) {
+		zero_user_segment(page, len, PAGE_SIZE);
+		return 0;
+	}
+
+	if (blkaddr == NEW_ADDR) {
+		zero_user_segment(page, 0, PAGE_SIZE);
+		SetPageUptodate(page);
+	} else {
+		err = f2fs_submit_page_read(inode, page, blkaddr);
+		if (err)
+			goto fail;
+
+		lock_page(page);
+		if (unlikely(page->mapping != mapping)) {
+			f2fs_put_page(page, 1);
+			goto repeat;
+		}
+		if (unlikely(!PageUptodate(page))) {
+			err = -EIO;
+			goto fail;
+		}
+	}
+	return 0;
+
+fail:
+	f2fs_put_page(page, 1);
+	f2fs_write_failed(mapping, pos + len);
+	if (drop_atomic)
+		f2fs_drop_inmem_pages_all(sbi, false);
+	return err;
+}
+
+static int f2fs_write_end(struct file *file,
+			struct address_space *mapping,
+			loff_t pos, unsigned len, unsigned copied,
+			struct page *page, void *fsdata)
+{
+	struct inode *inode = page->mapping->host;
+
+	trace_f2fs_write_end(inode, pos, len, copied);
+
+	/*
+	 * This should be come from len == PAGE_SIZE, and we expect copied
+	 * should be PAGE_SIZE. Otherwise, we treat it with zero copied and
+	 * let generic_perform_write() try to copy data again through copied=0.
+	 */
+	if (!PageUptodate(page)) {
+		if (unlikely(copied != len))
+			copied = 0;
+		else
+			SetPageUptodate(page);
+	}
+	if (!copied)
+		goto unlock_out;
+
+	set_page_dirty(page);
+
+	if (pos + copied > i_size_read(inode))
+		f2fs_i_size_write(inode, pos + copied);
+unlock_out:
+	f2fs_put_page(page, 1);
+	f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
+	return copied;
+}
+
+static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
+			   loff_t offset)
+{
+	unsigned i_blkbits = READ_ONCE(inode->i_blkbits);
+	unsigned blkbits = i_blkbits;
+	unsigned blocksize_mask = (1 << blkbits) - 1;
+	unsigned long align = offset | iov_iter_alignment(iter);
+	struct block_device *bdev = inode->i_sb->s_bdev;
+
+	if (iov_iter_rw(iter) == READ && offset >= i_size_read(inode))
+		return 1;
+
+	if (align & blocksize_mask) {
+		if (bdev)
+			blkbits = blksize_bits(bdev_logical_block_size(bdev));
+		blocksize_mask = (1 << blkbits) - 1;
+		if (align & blocksize_mask)
+			return -EINVAL;
+		return 1;
+	}
+	return 0;
+}
+
+static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
+{
+	struct address_space *mapping = iocb->ki_filp->f_mapping;
+	struct inode *inode = mapping->host;
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	size_t count = iov_iter_count(iter);
+	loff_t offset = iocb->ki_pos;
+	int rw = iov_iter_rw(iter);
+	int err;
+	enum rw_hint hint = iocb->ki_hint;
+	int whint_mode = F2FS_OPTION(sbi).whint_mode;
+
+	err = check_direct_IO(inode, iter, offset);
+	if (err)
+		return err < 0 ? err : 0;
+
+	if (f2fs_force_buffered_io(inode, rw))
+		return 0;
+
+	trace_f2fs_direct_IO_enter(inode, offset, count, rw);
+
+	if (rw == WRITE && whint_mode == WHINT_MODE_OFF)
+		iocb->ki_hint = WRITE_LIFE_NOT_SET;
+
+	if (!down_read_trylock(&F2FS_I(inode)->i_gc_rwsem[rw])) {
+		if (iocb->ki_flags & IOCB_NOWAIT) {
+			iocb->ki_hint = hint;
+			err = -EAGAIN;
+			goto out;
+		}
+		down_read(&F2FS_I(inode)->i_gc_rwsem[rw]);
+	}
+
+	err = blockdev_direct_IO(iocb, inode, iter, get_data_block_dio);
+	up_read(&F2FS_I(inode)->i_gc_rwsem[rw]);
+
+	if (rw == WRITE) {
+		if (whint_mode == WHINT_MODE_OFF)
+			iocb->ki_hint = hint;
+		if (err > 0) {
+			f2fs_update_iostat(F2FS_I_SB(inode), APP_DIRECT_IO,
+									err);
+			set_inode_flag(inode, FI_UPDATE_WRITE);
+		} else if (err < 0) {
+			f2fs_write_failed(mapping, offset + count);
+		}
+	}
+
+out:
+	trace_f2fs_direct_IO_exit(inode, offset, count, rw, err);
+
+	return err;
+}
+
+void f2fs_invalidate_page(struct page *page, unsigned int offset,
+							unsigned int length)
+{
+	struct inode *inode = page->mapping->host;
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+
+	if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
+		(offset % PAGE_SIZE || length != PAGE_SIZE))
+		return;
+
+	if (PageDirty(page)) {
+		if (inode->i_ino == F2FS_META_INO(sbi)) {
+			dec_page_count(sbi, F2FS_DIRTY_META);
+		} else if (inode->i_ino == F2FS_NODE_INO(sbi)) {
+			dec_page_count(sbi, F2FS_DIRTY_NODES);
+		} else {
+			inode_dec_dirty_pages(inode);
+			f2fs_remove_dirty_inode(inode);
+		}
+	}
+
+	clear_cold_data(page);
+
+	/* This is atomic written page, keep Private */
+	if (IS_ATOMIC_WRITTEN_PAGE(page))
+		return f2fs_drop_inmem_page(inode, page);
+
+	set_page_private(page, 0);
+	ClearPagePrivate(page);
+}
+
+int f2fs_release_page(struct page *page, gfp_t wait)
+{
+	/* If this is dirty page, keep PagePrivate */
+	if (PageDirty(page))
+		return 0;
+
+	/* This is atomic written page, keep Private */
+	if (IS_ATOMIC_WRITTEN_PAGE(page))
+		return 0;
+
+	clear_cold_data(page);
+	set_page_private(page, 0);
+	ClearPagePrivate(page);
+	return 1;
+}
+
+static int f2fs_set_data_page_dirty(struct page *page)
+{
+	struct address_space *mapping = page->mapping;
+	struct inode *inode = mapping->host;
+
+	trace_f2fs_set_page_dirty(page, DATA);
+
+	if (!PageUptodate(page))
+		SetPageUptodate(page);
+
+	if (f2fs_is_atomic_file(inode) && !f2fs_is_commit_atomic_write(inode)) {
+		if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
+			f2fs_register_inmem_page(inode, page);
+			return 1;
+		}
+		/*
+		 * Previously, this page has been registered, we just
+		 * return here.
+		 */
+		return 0;
+	}
+
+	if (!PageDirty(page)) {
+		__set_page_dirty_nobuffers(page);
+		f2fs_update_dirty_page(inode, page);
+		return 1;
+	}
+	return 0;
+}
+
+static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
+{
+	struct inode *inode = mapping->host;
+
+	if (f2fs_has_inline_data(inode))
+		return 0;
+
+	/* make sure allocating whole blocks */
+	if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
+		filemap_write_and_wait(mapping);
+
+	return generic_block_bmap(mapping, block, get_data_block_bmap);
+}
+
+#ifdef CONFIG_MIGRATION
+#include <linux/migrate.h>
+
+int f2fs_migrate_page(struct address_space *mapping,
+		struct page *newpage, struct page *page, enum migrate_mode mode)
+{
+	int rc, extra_count;
+	struct f2fs_inode_info *fi = F2FS_I(mapping->host);
+	bool atomic_written = IS_ATOMIC_WRITTEN_PAGE(page);
+
+	BUG_ON(PageWriteback(page));
+
+	/* migrating an atomic written page is safe with the inmem_lock hold */
+	if (atomic_written) {
+		if (mode != MIGRATE_SYNC)
+			return -EBUSY;
+		if (!mutex_trylock(&fi->inmem_lock))
+			return -EAGAIN;
+	}
+
+	/*
+	 * A reference is expected if PagePrivate set when move mapping,
+	 * however F2FS breaks this for maintaining dirty page counts when
+	 * truncating pages. So here adjusting the 'extra_count' make it work.
+	 */
+	extra_count = (atomic_written ? 1 : 0) - page_has_private(page);
+	rc = migrate_page_move_mapping(mapping, newpage,
+				page, NULL, mode, extra_count);
+	if (rc != MIGRATEPAGE_SUCCESS) {
+		if (atomic_written)
+			mutex_unlock(&fi->inmem_lock);
+		return rc;
+	}
+
+	if (atomic_written) {
+		struct inmem_pages *cur;
+		list_for_each_entry(cur, &fi->inmem_pages, list)
+			if (cur->page == page) {
+				cur->page = newpage;
+				break;
+			}
+		mutex_unlock(&fi->inmem_lock);
+		put_page(page);
+		get_page(newpage);
+	}
+
+	if (PagePrivate(page))
+		SetPagePrivate(newpage);
+	set_page_private(newpage, page_private(page));
+
+	if (mode != MIGRATE_SYNC_NO_COPY)
+		migrate_page_copy(newpage, page);
+	else
+		migrate_page_states(newpage, page);
+
+	return MIGRATEPAGE_SUCCESS;
+}
+#endif
+
+const struct address_space_operations f2fs_dblock_aops = {
+	.readpage	= f2fs_read_data_page,
+	.readpages	= f2fs_read_data_pages,
+	.writepage	= f2fs_write_data_page,
+	.writepages	= f2fs_write_data_pages,
+	.write_begin	= f2fs_write_begin,
+	.write_end	= f2fs_write_end,
+	.set_page_dirty	= f2fs_set_data_page_dirty,
+	.invalidatepage	= f2fs_invalidate_page,
+	.releasepage	= f2fs_release_page,
+	.direct_IO	= f2fs_direct_IO,
+	.bmap		= f2fs_bmap,
+#ifdef CONFIG_MIGRATION
+	.migratepage    = f2fs_migrate_page,
+#endif
+};
+
+void f2fs_clear_radix_tree_dirty_tag(struct page *page)
+{
+	struct address_space *mapping = page_mapping(page);
+	unsigned long flags;
+
+	xa_lock_irqsave(&mapping->i_pages, flags);
+	radix_tree_tag_clear(&mapping->i_pages, page_index(page),
+						PAGECACHE_TAG_DIRTY);
+	xa_unlock_irqrestore(&mapping->i_pages, flags);
+}
+
+int __init f2fs_init_post_read_processing(void)
+{
+	bio_post_read_ctx_cache = KMEM_CACHE(bio_post_read_ctx, 0);
+	if (!bio_post_read_ctx_cache)
+		goto fail;
+	bio_post_read_ctx_pool =
+		mempool_create_slab_pool(NUM_PREALLOC_POST_READ_CTXS,
+					 bio_post_read_ctx_cache);
+	if (!bio_post_read_ctx_pool)
+		goto fail_free_cache;
+	return 0;
+
+fail_free_cache:
+	kmem_cache_destroy(bio_post_read_ctx_cache);
+fail:
+	return -ENOMEM;
+}
+
+void __exit f2fs_destroy_post_read_processing(void)
+{
+	mempool_destroy(bio_post_read_ctx_pool);
+	kmem_cache_destroy(bio_post_read_ctx_cache);
+}