/*
 * NOTE: ipage is grabbed by caller, but if any error occurs, we should
 * release ipage in this function.
 */
static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
				struct f2fs_inline_dentry *inline_dentry)
{
	struct page *page;
	struct dnode_of_data dn;
	struct f2fs_dentry_block *dentry_blk;
	int err;

	page = grab_cache_page(dir->i_mapping, 0);
	if (!page) {
		f2fs_put_page(ipage, 1);
		return -ENOMEM;
	}

	set_new_dnode(&dn, dir, ipage, NULL, 0);
	err = f2fs_reserve_block(&dn, 0);
	if (err)
		goto out;

	f2fs_wait_on_page_writeback(page, DATA);
	zero_user_segment(page, MAX_INLINE_DATA, PAGE_CACHE_SIZE);

	dentry_blk = kmap_atomic(page);

	/* copy data from inline dentry block to new dentry block */
	memcpy(dentry_blk->dentry_bitmap, inline_dentry->dentry_bitmap,
					INLINE_DENTRY_BITMAP_SIZE);
	memset(dentry_blk->dentry_bitmap + INLINE_DENTRY_BITMAP_SIZE, 0,
			SIZE_OF_DENTRY_BITMAP - INLINE_DENTRY_BITMAP_SIZE);
	/*
	 * we do not need to zero out remainder part of dentry and filename
	 * field, since we have used bitmap for marking the usage status of
	 * them, besides, we can also ignore copying/zeroing reserved space
	 * of dentry block, because them haven't been used so far.
	 */
	memcpy(dentry_blk->dentry, inline_dentry->dentry,
			sizeof(struct f2fs_dir_entry) * NR_INLINE_DENTRY);
	memcpy(dentry_blk->filename, inline_dentry->filename,
					NR_INLINE_DENTRY * F2FS_SLOT_LEN);

	kunmap_atomic(dentry_blk);
	SetPageUptodate(page);
	set_page_dirty(page);

	/* clear inline dir and flag after data writeback */
	truncate_inline_inode(ipage, 0);

	stat_dec_inline_dir(dir);
	clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);

	if (i_size_read(dir) < PAGE_CACHE_SIZE) {
		i_size_write(dir, PAGE_CACHE_SIZE);
		set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
	}

	sync_inode_page(&dn);
out:
	f2fs_put_page(page, 1);
	return err;
}

static int expand_inode_data(struct inode *inode, loff_t offset,
					loff_t len, int mode)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	pgoff_t index, pg_start, pg_end;
	loff_t new_size = i_size_read(inode);
	loff_t off_start, off_end;
	int ret = 0;

	f2fs_balance_fs(sbi);

	ret = inode_newsize_ok(inode, (len + offset));
	if (ret)
		return ret;

	if (f2fs_has_inline_data(inode)) {
		ret = f2fs_convert_inline_inode(inode);
		if (ret)
			return ret;
	}

	pg_start = ((unsigned long long) offset) >> PAGE_CACHE_SHIFT;
	pg_end = ((unsigned long long) offset + len) >> PAGE_CACHE_SHIFT;

	off_start = offset & (PAGE_CACHE_SIZE - 1);
	off_end = (offset + len) & (PAGE_CACHE_SIZE - 1);

	f2fs_lock_op(sbi);

	for (index = pg_start; index <= pg_end; index++) {
		struct dnode_of_data dn;

		if (index == pg_end && !off_end)
			goto noalloc;

		set_new_dnode(&dn, inode, NULL, NULL, 0);
		ret = f2fs_reserve_block(&dn, index);
		if (ret)
			break;
noalloc:
		if (pg_start == pg_end)
			new_size = offset + len;
		else if (index == pg_start && off_start)
			new_size = (index + 1) << PAGE_CACHE_SHIFT;
		else if (index == pg_end)
			new_size = (index << PAGE_CACHE_SHIFT) + off_end;
		else
			new_size += PAGE_CACHE_SIZE;
	}

	if (!(mode & FALLOC_FL_KEEP_SIZE) &&
		i_size_read(inode) < new_size) {
		i_size_write(inode, new_size);
		mark_inode_dirty(inode);
		update_inode_page(inode);
	}
	f2fs_unlock_op(sbi);

	return ret;
}

static int f2fs_vm_page_mkwrite(struct vm_area_struct *vma,
						struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = file_inode(vma->vm_file);
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	struct dnode_of_data dn;
	int err;

	f2fs_balance_fs(sbi);

	vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);

	f2fs_bug_on(sbi, f2fs_has_inline_data(inode));

	/* block allocation */
	f2fs_lock_op(sbi);
	set_new_dnode(&dn, inode, NULL, NULL, 0);
	err = f2fs_reserve_block(&dn, page->index);
	if (err) {
		f2fs_unlock_op(sbi);
		goto out;
	}
	f2fs_put_dnode(&dn);
	f2fs_unlock_op(sbi);

	file_update_time(vma->vm_file);
	lock_page(page);
	if (unlikely(page->mapping != inode->i_mapping ||
			page_offset(page) > i_size_read(inode) ||
			!PageUptodate(page))) {
		unlock_page(page);
		err = -EFAULT;
		goto out;
	}

	/*
	 * check to see if the page is mapped already (no holes)
	 */
	if (PageMappedToDisk(page))
		goto mapped;

	/* page is wholly or partially inside EOF */
	if (((page->index + 1) << PAGE_CACHE_SHIFT) > i_size_read(inode)) {
		unsigned offset;
		offset = i_size_read(inode) & ~PAGE_CACHE_MASK;
		zero_user_segment(page, offset, PAGE_CACHE_SIZE);
	}
	set_page_dirty(page);
	SetPageUptodate(page);

	trace_f2fs_vm_page_mkwrite(page, DATA);
mapped:
	/* fill the page */
	f2fs_wait_on_page_writeback(page, DATA);
	/* if gced page is attached, don't write to cold segment */
	clear_cold_data(page);
out:
	return block_page_mkwrite_return(err);
}

int truncate_blocks(struct inode *inode, u64 from, bool lock)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	unsigned int blocksize = inode->i_sb->s_blocksize;
	struct dnode_of_data dn;
	pgoff_t free_from;
	int count = 0, err = 0;
	struct page *ipage;

	trace_f2fs_truncate_blocks_enter(inode, from);

	free_from = (pgoff_t)F2FS_BYTES_TO_BLK(from + blocksize - 1);

	if (lock)
		f2fs_lock_op(sbi);

	ipage = get_node_page(sbi, inode->i_ino);
	if (IS_ERR(ipage)) {
		err = PTR_ERR(ipage);
		goto out;
	}

	if (f2fs_has_inline_data(inode)) {
		f2fs_put_page(ipage, 1);
		goto out;
	}

	set_new_dnode(&dn, inode, ipage, NULL, 0);
	err = get_dnode_of_data(&dn, free_from, LOOKUP_NODE);
	if (err) {
		if (err == -ENOENT)
			goto free_next;
		goto out;
	}

	count = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));

	count -= dn.ofs_in_node;
	f2fs_bug_on(sbi, count < 0);

	if (dn.ofs_in_node || IS_INODE(dn.node_page)) {
		truncate_data_blocks_range(&dn, count);
		free_from += count;
	}

	f2fs_put_dnode(&dn);
free_next:
	err = truncate_inode_blocks(inode, free_from);
out:
	if (lock)
		f2fs_unlock_op(sbi);

	/* lastly zero out the first data page */
	if (!err)
		err = truncate_partial_data_page(inode, from);

	trace_f2fs_truncate_blocks_exit(inode, err);
	return err;
}

static int find_in_level(struct f2fs_sb_info *sbi,struct f2fs_node *dir,
		unsigned int level, struct dentry *de)
{
	unsigned int nbucket, nblock;
	unsigned int bidx, end_block;
	struct f2fs_dir_entry *dentry = NULL;
	struct dnode_of_data dn;
	void *dentry_blk;
	int max_slots = 214;
	nid_t ino = le32_to_cpu(dir->footer.ino);
	f2fs_hash_t namehash;
	unsigned int dir_level = dir->i.i_dir_level;
	int ret = 0;

	namehash = f2fs_dentry_hash(de->name, de->len);

	nbucket = dir_buckets(level, dir_level);
	nblock = bucket_blocks(level);

	bidx = dir_block_index(level, dir_level, le32_to_cpu(namehash) % nbucket);
	end_block = bidx + nblock;

	dentry_blk = calloc(BLOCK_SZ, 1);
	ASSERT(dentry_blk);

	memset(&dn, 0, sizeof(dn));
	for (; bidx < end_block; bidx++) {

		/* Firstly, we should know direct node of target data blk */
		if (dn.node_blk && dn.node_blk != dn.inode_blk)
			free(dn.node_blk);

		set_new_dnode(&dn, dir, NULL, ino);
		get_dnode_of_data(sbi, &dn, bidx, LOOKUP_NODE);
		if (dn.data_blkaddr == NULL_ADDR)
			continue;

		ret = dev_read_block(dentry_blk, dn.data_blkaddr);
		ASSERT(ret >= 0);

		dentry = find_in_block(dentry_blk, de->name, de->len,
						namehash, &max_slots);
		if (dentry) {
			ret = 1;
			de->ino = le32_to_cpu(dentry->ino);
			break;
		}
	}

	if (dn.node_blk && dn.node_blk != dn.inode_blk)
		free(dn.node_blk);
	free(dentry_blk);

	return ret;
}

static void __allocate_data_blocks(struct inode *inode, loff_t offset,
							size_t count)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	struct dnode_of_data dn;
	u64 start = F2FS_BYTES_TO_BLK(offset);
	u64 len = F2FS_BYTES_TO_BLK(count);
	bool allocated;
	u64 end_offset;

	while (len) {
		f2fs_balance_fs(sbi);
		f2fs_lock_op(sbi);

		/* When reading holes, we need its node page */
		set_new_dnode(&dn, inode, NULL, NULL, 0);
		if (get_dnode_of_data(&dn, start, ALLOC_NODE))
			goto out;

		allocated = false;
		end_offset = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));

		while (dn.ofs_in_node < end_offset && len) {
			block_t blkaddr;

			if (unlikely(f2fs_cp_error(sbi)))
				goto sync_out;

			blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);
			if (blkaddr == NULL_ADDR || blkaddr == NEW_ADDR) {
				if (__allocate_data_block(&dn))
					goto sync_out;
				allocated = true;
			}
			len--;
			start++;
			dn.ofs_in_node++;
		}

		if (allocated)
			sync_inode_page(&dn);

		f2fs_put_dnode(&dn);
		f2fs_unlock_op(sbi);
	}
	return;

sync_out:
	if (allocated)
		sync_inode_page(&dn);
	f2fs_put_dnode(&dn);
out:
	f2fs_unlock_op(sbi);
	return;
}

int 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;
    int err = 0;

    set_new_dnode(&dn, inode, NULL, NULL, 0);
    err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
    if (err)
        return err;

    fio->blk_addr = dn.data_blkaddr;

    /* This page is already truncated */
    if (fio->blk_addr == NULL_ADDR) {
        ClearPageUptodate(page);
        goto out_writepage;
    }

    if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
        fio->encrypted_page = f2fs_encrypt(inode, fio->page);
        if (IS_ERR(fio->encrypted_page)) {
            err = PTR_ERR(fio->encrypted_page);
            goto out_writepage;
        }
    }

    set_page_writeback(page);

    /*
     * If current allocation needs SSR,
     * it had better in-place writes for updated data.
     */
    if (unlikely(fio->blk_addr != NEW_ADDR &&
                 !is_cold_data(page) &&
                 need_inplace_update(inode))) {
        rewrite_data_page(fio);
        set_inode_flag(F2FS_I(inode), FI_UPDATE_WRITE);
        trace_f2fs_do_write_data_page(page, IPU);
    } else {
        write_data_page(&dn, fio);
        set_data_blkaddr(&dn);
        f2fs_update_extent_cache(&dn);
        trace_f2fs_do_write_data_page(page, OPU);
        set_inode_flag(F2FS_I(inode), FI_APPEND_WRITE);
        if (page->index == 0)
            set_inode_flag(F2FS_I(inode), FI_FIRST_BLOCK_WRITTEN);
    }
out_writepage:
    f2fs_put_dnode(&dn);
    return err;
}

/*
 * 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 *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;
repeat:
    page = grab_cache_page(mapping, index);
    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_CACHE_SIZE);
        SetPageUptodate(page);
    } else {
        f2fs_put_page(page, 1);

        page = get_read_data_page(inode, index, READ_SYNC);
        if (IS_ERR(page))
            goto repeat;

        /* wait for read completion */
        lock_page(page);
    }
got_it:
    if (new_i_size &&
            i_size_read(inode) < ((index + 1) << PAGE_CACHE_SHIFT)) {
        i_size_write(inode, ((index + 1) << PAGE_CACHE_SHIFT));
        /* Only the directory inode sets new_i_size */
        set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR);
    }
    return page;
}

static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
                                   struct f2fs_inline_dentry *inline_dentry)
{
    struct page *page;
    struct dnode_of_data dn;
    struct f2fs_dentry_block *dentry_blk;
    int err;

    page = grab_cache_page(dir->i_mapping, 0);
    if (!page)
        return -ENOMEM;

    set_new_dnode(&dn, dir, ipage, NULL, 0);
    err = f2fs_reserve_block(&dn, 0);
    if (err)
        goto out;

    f2fs_wait_on_page_writeback(page, DATA);
    zero_user_segment(page, 0, PAGE_CACHE_SIZE);

    dentry_blk = kmap_atomic(page);

    /* copy data from inline dentry block to new dentry block */
    memcpy(dentry_blk->dentry_bitmap, inline_dentry->dentry_bitmap,
           INLINE_DENTRY_BITMAP_SIZE);
    memcpy(dentry_blk->dentry, inline_dentry->dentry,
           sizeof(struct f2fs_dir_entry) * NR_INLINE_DENTRY);
    memcpy(dentry_blk->filename, inline_dentry->filename,
           NR_INLINE_DENTRY * F2FS_SLOT_LEN);

    kunmap_atomic(dentry_blk);
    SetPageUptodate(page);
    set_page_dirty(page);

    /* clear inline dir and flag after data writeback */
    truncate_inline_inode(ipage, 0);

    stat_dec_inline_dir(dir);
    clear_inode_flag(F2FS_I(dir), FI_INLINE_DENTRY);

    if (i_size_read(dir) < PAGE_CACHE_SIZE) {
        i_size_write(dir, PAGE_CACHE_SIZE);
        set_inode_flag(F2FS_I(dir), FI_UPDATE_DIR);
    }

    sync_inode_page(&dn);
out:
    f2fs_put_page(page, 1);
    return err;
}

static int expand_inode_data(struct inode *inode, loff_t offset, loff_t len,
			     int mode)
{
	pgoff_t index, pg_start, pg_end;
	loff_t new_size = i_size_read(inode);
	loff_t off_start, off_end;
	struct dnode_of_data dn;
	int ret, ilock;
	struct hmfs_sb_info *sbi = HMFS_SB(inode->i_sb);

	ret = inode_newsize_ok(inode, (len + offset));
	if (ret)
		return ret;

	pg_start = ((u64) offset) >> HMFS_PAGE_SIZE_BITS;
	pg_end = ((u64) offset + len) >> HMFS_PAGE_SIZE_BITS;

	off_start = offset & (HMFS_PAGE_SIZE - 1);
	off_end = (offset + len) & (HMFS_PAGE_SIZE - 1);

	for (index = pg_start; index <= pg_end; index++) {
		ilock = mutex_lock_op(sbi);
		set_new_dnode(&dn, inode, NULL, NULL, 0);

		ret = get_dnode_of_data(&dn, index, ALLOC_NODE);
		mutex_unlock_op(sbi, ilock);
		if (ret) {
			break;
		}

		if (pg_start == pg_end)
			new_size = offset + len;
		else if (index == pg_start && off_start)
			new_size = (index + 1) << HMFS_PAGE_SIZE_BITS;
		else if (index == pg_end)
			new_size = (index << HMFS_PAGE_SIZE_BITS) + off_end;
		else
			new_size += HMFS_PAGE_SIZE;
	}

	if (!(mode & FALLOC_FL_KEEP_SIZE) && i_size_read(inode) < new_size) {
		mark_size_dirty(inode, new_size);
	}

	return ret;
}

int truncate_hole(struct inode *inode, pgoff_t start, pgoff_t end)
{
	pgoff_t index;
	int err;
	struct dnode_of_data dn;

	for (index = start; index < end; index++) {
		set_new_dnode(&dn, inode, NULL, NULL, 0);
		err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
		if (err) {
			if (err == -ENODATA)
				continue;
			return err;
		}
		truncate_data_blocks_range(&dn, 1);
	}
	return 0;
}

int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end)
{
	pgoff_t index;
	int err;

	for (index = pg_start; index < pg_end; index++) {
		struct dnode_of_data dn;

		set_new_dnode(&dn, inode, NULL, NULL, 0);
		err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
		if (err) {
			if (err == -ENOENT)
				continue;
			return err;
		}

		if (dn.data_blkaddr != NULL_ADDR)
			truncate_data_blocks_range(&dn, 1);
		f2fs_put_dnode(&dn);
	}
	return 0;
}

static int truncate_blocks(struct inode *inode, u64 from)
{
	struct dnode_of_data dn;
	struct hmfs_sb_info *sbi = HMFS_SB(inode->i_sb);
	int count, err;
	u64 free_from;
	int ilock;

	free_from = (from + HMFS_PAGE_SIZE - 1) >> HMFS_PAGE_SIZE_BITS;

	ilock = mutex_lock_op(sbi);

	set_new_dnode(&dn, inode, NULL, NULL, 0);
	err = get_dnode_of_data(&dn, free_from, LOOKUP_NODE);

	if (err) {
		goto free_next;
	}
	if (!dn.level)
		count = NORMAL_ADDRS_PER_INODE;
	else
		count = ADDRS_PER_BLOCK;

	count -= dn.ofs_in_node;
	BUG_ON(count < 0);

	if (dn.ofs_in_node || !dn.level) {
		truncate_data_blocks_range(&dn, count);
		free_from += count;
	}

free_next:err = truncate_inode_blocks(inode, free_from);
	truncate_partial_data_page(inode, from);

	mutex_unlock_op(sbi, ilock);
	return err;
}

static inline int write_all_xattrs(struct inode *inode, __u32 hsize,
				void *txattr_addr, struct page *ipage)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	size_t inline_size = 0;
	void *xattr_addr;
	struct page *xpage;
	nid_t new_nid = 0;
	int err;

	inline_size = inline_xattr_size(inode);

	if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
		if (!alloc_nid(sbi, &new_nid))
			return -ENOSPC;

	/* write to inline xattr */
	if (inline_size) {
		struct page *page = NULL;
		void *inline_addr;

		if (ipage) {
			inline_addr = inline_xattr_addr(ipage);
			f2fs_wait_on_page_writeback(ipage, NODE, true);
			set_page_dirty(ipage);
		} else {
			page = get_node_page(sbi, inode->i_ino);
			if (IS_ERR(page)) {
				alloc_nid_failed(sbi, new_nid);
				return PTR_ERR(page);
			}
			inline_addr = inline_xattr_addr(page);
			f2fs_wait_on_page_writeback(page, NODE, true);
		}
		memcpy(inline_addr, txattr_addr, inline_size);
		f2fs_put_page(page, 1);

		/* no need to use xattr node block */
		if (hsize <= inline_size) {
			err = truncate_xattr_node(inode, ipage);
			alloc_nid_failed(sbi, new_nid);
			return err;
		}
	}

	/* write to xattr node block */
	if (F2FS_I(inode)->i_xattr_nid) {
		xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
		if (IS_ERR(xpage)) {
			alloc_nid_failed(sbi, new_nid);
			return PTR_ERR(xpage);
		}
		f2fs_bug_on(sbi, new_nid);
		f2fs_wait_on_page_writeback(xpage, NODE, true);
	} else {
		struct dnode_of_data dn;
		set_new_dnode(&dn, inode, NULL, NULL, new_nid);
		xpage = new_node_page(&dn, XATTR_NODE_OFFSET, ipage);
		if (IS_ERR(xpage)) {
			alloc_nid_failed(sbi, new_nid);
			return PTR_ERR(xpage);
		}
		alloc_nid_done(sbi, new_nid);
	}

	xattr_addr = page_address(xpage);
	memcpy(xattr_addr, txattr_addr + inline_size, PAGE_SIZE -
						sizeof(struct node_footer));
	set_page_dirty(xpage);
	f2fs_put_page(xpage, 1);

	/* need to checkpoint during fsync */
	F2FS_I(inode)->xattr_ver = cur_cp_version(F2FS_CKPT(sbi));
	return 0;
}

int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page)
{
	struct f2fs_io_info fio = {
		.sbi = F2FS_I_SB(dn->inode),
		.type = DATA,
		.op = REQ_OP_WRITE,
		.op_flags = REQ_SYNC | REQ_PRIO,
		.page = page,
		.encrypted_page = NULL,
	};
	int dirty, err;

	if (!f2fs_exist_data(dn->inode))
		goto clear_out;

	err = f2fs_reserve_block(dn, 0);
	if (err)
		return err;

	f2fs_bug_on(F2FS_P_SB(page), PageWriteback(page));

	read_inline_data(page, dn->inode_page);
	set_page_dirty(page);

	/* clear dirty state */
	dirty = clear_page_dirty_for_io(page);

	/* write data page to try to make data consistent */
	set_page_writeback(page);
	fio.old_blkaddr = dn->data_blkaddr;
	set_inode_flag(dn->inode, FI_HOT_DATA);
	write_data_page(dn, &fio);
	f2fs_wait_on_page_writeback(page, DATA, true);
	if (dirty) {
		inode_dec_dirty_pages(dn->inode);
		remove_dirty_inode(dn->inode);
	}

	/* this converted inline_data should be recovered. */
	set_inode_flag(dn->inode, FI_APPEND_WRITE);

	/* clear inline data and flag after data writeback */
	truncate_inline_inode(dn->inode, dn->inode_page, 0);
	clear_inline_node(dn->inode_page);
clear_out:
	stat_dec_inline_inode(dn->inode);
	clear_inode_flag(dn->inode, FI_INLINE_DATA);
	f2fs_put_dnode(dn);
	return 0;
}

int f2fs_convert_inline_inode(struct inode *inode)
{
	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
	struct dnode_of_data dn;
	struct page *ipage, *page;
	int err = 0;

	if (!f2fs_has_inline_data(inode))
		return 0;

	page = f2fs_grab_cache_page(inode->i_mapping, 0, false);
	if (!page)
		return -ENOMEM;

	f2fs_lock_op(sbi);

	ipage = get_node_page(sbi, inode->i_ino);
	if (IS_ERR(ipage)) {
		err = PTR_ERR(ipage);
		goto out;
	}

	set_new_dnode(&dn, inode, ipage, ipage, 0);

	if (f2fs_has_inline_data(inode))
		err = f2fs_convert_inline_page(&dn, page);

	f2fs_put_dnode(&dn);
out:
	f2fs_unlock_op(sbi);

	f2fs_put_page(page, 1);

	f2fs_balance_fs(sbi, dn.node_changed);

	return err;
}

int f2fs_write_inline_data(struct inode *inode, struct page *page)
{
	void *src_addr, *dst_addr;
	struct dnode_of_data dn;
	int err;

	set_new_dnode(&dn, inode, NULL, NULL, 0);
	err = get_dnode_of_data(&dn, 0, LOOKUP_NODE);
	if (err)
		return err;

//.........这里部分代码省略.........

static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
{
	int err;
	struct page *ipage;
	struct dnode_of_data dn;
	void *src_addr, *dst_addr;
	block_t new_blk_addr;
	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
	struct f2fs_io_info fio = {
		.type = DATA,
		.rw = WRITE_SYNC | REQ_PRIO,
	};

	f2fs_lock_op(sbi);
	ipage = get_node_page(sbi, inode->i_ino);
	if (IS_ERR(ipage))
		return PTR_ERR(ipage);

	/*
	 * i_addr[0] is not used for inline data,
	 * so reserving new block will not destroy inline data
	 */
	set_new_dnode(&dn, inode, ipage, NULL, 0);
	err = f2fs_reserve_block(&dn, 0);
	if (err) {
		f2fs_unlock_op(sbi);
		return err;
	}

	zero_user_segment(page, MAX_INLINE_DATA, PAGE_CACHE_SIZE);

	/* Copy the whole inline data block */
	src_addr = inline_data_addr(ipage);
	dst_addr = kmap(page);
	memcpy(dst_addr, src_addr, MAX_INLINE_DATA);
	kunmap(page);
	SetPageUptodate(page);

	/* write data page to try to make data consistent */
	set_page_writeback(page);
	write_data_page(page, &dn, &new_blk_addr, &fio);
	update_extent_cache(new_blk_addr, &dn);
	f2fs_wait_on_page_writeback(page, DATA);

	/* clear inline data and flag after data writeback */
	zero_user_segment(ipage, INLINE_DATA_OFFSET,
				 INLINE_DATA_OFFSET + MAX_INLINE_DATA);
	clear_inode_flag(F2FS_I(inode), FI_INLINE_DATA);
	stat_dec_inline_inode(inode);

	sync_inode_page(&dn);
	f2fs_put_dnode(&dn);
	f2fs_unlock_op(sbi);
	return err;
}

int f2fs_convert_inline_data(struct inode *inode, pgoff_t to_size)
{
	struct page *page;
	int err;

	if (!f2fs_has_inline_data(inode))
		return 0;
	else if (to_size <= MAX_INLINE_DATA)
		return 0;

	page = grab_cache_page_write_begin(inode->i_mapping, 0, AOP_FLAG_NOFS);
	if (!page)
		return -ENOMEM;

	err = __f2fs_convert_inline_data(inode, page);
	f2fs_put_page(page, 1);
	return err;
}

int f2fs_write_inline_data(struct inode *inode,
			   struct page *page, unsigned size)
{
	void *src_addr, *dst_addr;
	struct page *ipage;
	struct dnode_of_data dn;
	int err;

	set_new_dnode(&dn, inode, NULL, NULL, 0);
	err = get_dnode_of_data(&dn, 0, LOOKUP_NODE);
	if (err)
		return err;
	ipage = dn.inode_page;

	zero_user_segment(ipage, INLINE_DATA_OFFSET,
				 INLINE_DATA_OFFSET + MAX_INLINE_DATA);
	src_addr = kmap(page);
	dst_addr = inline_data_addr(ipage);
	memcpy(dst_addr, src_addr, size);
	kunmap(page);

	/* Release the first data block if it is allocated */
	if (!f2fs_has_inline_data(inode)) {
		truncate_data_blocks_range(&dn, 1);
		set_inode_flag(F2FS_I(inode), FI_INLINE_DATA);
//.........这里部分代码省略.........

static int do_recover_data(struct f2fs_sb_info *sbi, struct inode *inode,
					struct page *page)
{
	struct dnode_of_data dn;
	struct node_info ni;
	unsigned int start, end;
	int err = 0, recovered = 0;

	/* step 1: recover xattr */
	if (IS_INODE(page)) {
		f2fs_recover_inline_xattr(inode, page);
	} else if (f2fs_has_xattr_block(ofs_of_node(page))) {
		err = f2fs_recover_xattr_data(inode, page);
		if (!err)
			recovered++;
		goto out;
	}

	/* step 2: recover inline data */
	if (f2fs_recover_inline_data(inode, page))
		goto out;

	/* step 3: recover data indices */
	start = f2fs_start_bidx_of_node(ofs_of_node(page), inode);
	end = start + ADDRS_PER_PAGE(page, inode);

	set_new_dnode(&dn, inode, NULL, NULL, 0);
retry_dn:
	err = f2fs_get_dnode_of_data(&dn, start, ALLOC_NODE);
	if (err) {
		if (err == -ENOMEM) {
			congestion_wait(BLK_RW_ASYNC, HZ/50);
			goto retry_dn;
		}
		goto out;
	}

	f2fs_wait_on_page_writeback(dn.node_page, NODE, true, true);

	err = f2fs_get_node_info(sbi, dn.nid, &ni);
	if (err)
		goto err;

	f2fs_bug_on(sbi, ni.ino != ino_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;

		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;

		/* dest is invalid, just invalidate src block */
		if (dest == NULL_ADDR) {
			f2fs_truncate_data_blocks_range(&dn, 1);
			continue;
		}

		if (!file_keep_isize(inode) &&
			(i_size_read(inode) <= ((loff_t)start << PAGE_SHIFT)))
			f2fs_i_size_write(inode,
				(loff_t)(start + 1) << PAGE_SHIFT);

		/*
		 * dest is reserved block, invalidate src block
		 * and then reserve one new block in dnode page.
		 */
		if (dest == NEW_ADDR) {
			f2fs_truncate_data_blocks_range(&dn, 1);
			f2fs_reserve_new_block(&dn);
			continue;
		}

		/* dest is valid block, try to recover from src to dest */
		if (f2fs_is_valid_blkaddr(sbi, dest, META_POR)) {

//.........这里部分代码省略.........

int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page)
{
    void *src_addr, *dst_addr;
    struct f2fs_io_info fio = {
        .sbi = F2FS_I_SB(dn->inode),
        .type = DATA,
        .rw = WRITE_SYNC | REQ_PRIO,
        .page = page,
        .encrypted_page = NULL,
    };
    int dirty, err;

    f2fs_bug_on(F2FS_I_SB(dn->inode), page->index);

    if (!f2fs_exist_data(dn->inode))
        goto clear_out;

    err = f2fs_reserve_block(dn, 0);
    if (err)
        return err;

    f2fs_wait_on_page_writeback(page, DATA);

    if (PageUptodate(page))
        goto no_update;

    zero_user_segment(page, MAX_INLINE_DATA, PAGE_CACHE_SIZE);

    /* Copy the whole inline data block */
    src_addr = inline_data_addr(dn->inode_page);
    dst_addr = kmap_atomic(page);
    memcpy(dst_addr, src_addr, MAX_INLINE_DATA);
    flush_dcache_page(page);
    kunmap_atomic(dst_addr);
    SetPageUptodate(page);
no_update:
    set_page_dirty(page);

    /* clear dirty state */
    dirty = clear_page_dirty_for_io(page);

    /* write data page to try to make data consistent */
    set_page_writeback(page);
    fio.blk_addr = dn->data_blkaddr;
    write_data_page(dn, &fio);
    set_data_blkaddr(dn);
    f2fs_update_extent_cache(dn);
    f2fs_wait_on_page_writeback(page, DATA);
    if (dirty)
        inode_dec_dirty_pages(dn->inode);

    /* this converted inline_data should be recovered. */
    set_inode_flag(F2FS_I(dn->inode), FI_APPEND_WRITE);

    /* clear inline data and flag after data writeback */
    truncate_inline_inode(dn->inode_page, 0);
clear_out:
    stat_dec_inline_inode(dn->inode);
    f2fs_clear_inline_inode(dn->inode);
    sync_inode_page(dn);
    f2fs_put_dnode(dn);
    return 0;
}

int f2fs_convert_inline_inode(struct inode *inode)
{
    struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
    struct dnode_of_data dn;
    struct page *ipage, *page;
    int err = 0;

    page = grab_cache_page(inode->i_mapping, 0);
    if (!page)
        return -ENOMEM;

    f2fs_lock_op(sbi);

    ipage = get_node_page(sbi, inode->i_ino);
    if (IS_ERR(ipage)) {
        err = PTR_ERR(ipage);
        goto out;
    }

    set_new_dnode(&dn, inode, ipage, ipage, 0);

    if (f2fs_has_inline_data(inode))
        err = f2fs_convert_inline_page(&dn, page);

    f2fs_put_dnode(&dn);
out:
    f2fs_unlock_op(sbi);

    f2fs_put_page(page, 1);
    return err;
}

int f2fs_write_inline_data(struct inode *inode, struct page *page)
{
    void *src_addr, *dst_addr;
    struct dnode_of_data dn;
//.........这里部分代码省略.........

/*
 * 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
 */
static 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;
    int mode = create ? ALLOC_NODE : LOOKUP_NODE_RA;
    pgoff_t pgofs, end_offset;
    int err = 0, ofs = 1;
    struct extent_info ei;
    bool allocated = false;

    map->m_len = 0;
    map->m_flags = 0;

    /* it only supports block size == page size */
    pgofs =	(pgoff_t)map->m_lblk;

    if (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;
        goto out;
    }

    if (create)
        f2fs_lock_op(F2FS_I_SB(inode));

    /* When reading holes, we need its node page */
    set_new_dnode(&dn, inode, NULL, NULL, 0);
    err = get_dnode_of_data(&dn, pgofs, mode);
    if (err) {
        if (err == -ENOENT)
            err = 0;
        goto unlock_out;
    }
    if (dn.data_blkaddr == NEW_ADDR) {
        if (flag == F2FS_GET_BLOCK_BMAP) {
            err = -ENOENT;
            goto put_out;
        } else if (flag == F2FS_GET_BLOCK_READ ||
                   flag == F2FS_GET_BLOCK_DIO) {
            goto put_out;
        }
        /*
         * if it is in fiemap call path (flag = F2FS_GET_BLOCK_FIEMAP),
         * mark it as mapped and unwritten block.
         */
    }

    if (dn.data_blkaddr != NULL_ADDR) {
        map->m_flags = F2FS_MAP_MAPPED;
        map->m_pblk = dn.data_blkaddr;
        if (dn.data_blkaddr == NEW_ADDR)
            map->m_flags |= F2FS_MAP_UNWRITTEN;
    } else if (create) {
        err = __allocate_data_block(&dn);
        if (err)
            goto put_out;
        allocated = true;
        map->m_flags = F2FS_MAP_NEW | F2FS_MAP_MAPPED;
        map->m_pblk = dn.data_blkaddr;
    } else {
        if (flag == F2FS_GET_BLOCK_BMAP)
            err = -ENOENT;
        goto put_out;
    }

    end_offset = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));
    map->m_len = 1;
    dn.ofs_in_node++;
    pgofs++;

get_next:
    if (dn.ofs_in_node >= end_offset) {
        if (allocated)
            sync_inode_page(&dn);
        allocated = false;
        f2fs_put_dnode(&dn);

        set_new_dnode(&dn, inode, NULL, NULL, 0);
        err = get_dnode_of_data(&dn, pgofs, mode);
        if (err) {
            if (err == -ENOENT)
                err = 0;
            goto unlock_out;
        }

        if (dn.data_blkaddr == NEW_ADDR &&
                flag != F2FS_GET_BLOCK_FIEMAP)
            goto put_out;

//.........这里部分代码省略.........

static int check_index_in_prev_nodes(struct f2fs_sb_info *sbi,
			block_t blkaddr, struct dnode_of_data *dn)
{
	struct seg_entry *sentry;
	unsigned int segno = GET_SEGNO(sbi, blkaddr);
	unsigned short blkoff = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
	struct f2fs_summary_block *sum_node;
	struct f2fs_summary sum;
	struct page *sum_page, *node_page;
	struct dnode_of_data tdn = *dn;
	nid_t ino, nid;
	struct inode *inode;
	unsigned int offset;
	block_t bidx;
	int i;

	sentry = get_seg_entry(sbi, segno);
	if (!f2fs_test_bit(blkoff, sentry->cur_valid_map))
		return 0;

	/* Get the previous summary */
	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
		struct curseg_info *curseg = CURSEG_I(sbi, i);
		if (curseg->segno == segno) {
			sum = curseg->sum_blk->entries[blkoff];
			goto got_it;
		}
	}

	sum_page = f2fs_get_sum_page(sbi, segno);
	if (IS_ERR(sum_page))
		return PTR_ERR(sum_page);
	sum_node = (struct f2fs_summary_block *)page_address(sum_page);
	sum = sum_node->entries[blkoff];
	f2fs_put_page(sum_page, 1);
got_it:
	/* Use the locked dnode page and inode */
	nid = le32_to_cpu(sum.nid);
	if (dn->inode->i_ino == nid) {
		tdn.nid = nid;
		if (!dn->inode_page_locked)
			lock_page(dn->inode_page);
		tdn.node_page = dn->inode_page;
		tdn.ofs_in_node = le16_to_cpu(sum.ofs_in_node);
		goto truncate_out;
	} else if (dn->nid == nid) {
		tdn.ofs_in_node = le16_to_cpu(sum.ofs_in_node);
		goto truncate_out;
	}

	/* Get the node page */
	node_page = f2fs_get_node_page(sbi, nid);
	if (IS_ERR(node_page))
		return PTR_ERR(node_page);

	offset = ofs_of_node(node_page);
	ino = ino_of_node(node_page);
	f2fs_put_page(node_page, 1);

	if (ino != dn->inode->i_ino) {
		int ret;

		/* Deallocate previous index in the node page */
		inode = f2fs_iget_retry(sbi->sb, ino);
		if (IS_ERR(inode))
			return PTR_ERR(inode);

		ret = dquot_initialize(inode);
		if (ret) {
			iput(inode);
			return ret;
		}
	} else {
		inode = dn->inode;
	}

	bidx = f2fs_start_bidx_of_node(offset, inode) +
				le16_to_cpu(sum.ofs_in_node);

	/*
	 * if inode page is locked, unlock temporarily, but its reference
	 * count keeps alive.
	 */
	if (ino == dn->inode->i_ino && dn->inode_page_locked)
		unlock_page(dn->inode_page);

	set_new_dnode(&tdn, inode, NULL, NULL, 0);
	if (f2fs_get_dnode_of_data(&tdn, bidx, LOOKUP_NODE))
		goto out;

	if (tdn.data_blkaddr == blkaddr)
		f2fs_truncate_data_blocks_range(&tdn, 1);

	f2fs_put_dnode(&tdn);
out:
	if (ino != dn->inode->i_ino)
		iput(inode);
	else if (dn->inode_page_locked)
		lock_page(dn->inode_page);
	return 0;
//.........这里部分代码省略.........