static int rawfs_writepage(struct page *page, struct writeback_control *wbc)
{
	struct address_space *mapping = page->mapping;
	struct inode *inode;
	unsigned long end_index;
	char *buffer;
	int n_written = 0;
	unsigned n_bytes;
	loff_t i_size;

	if (!mapping)
		BUG();
	inode = mapping->host;
	if (!inode)
		BUG();
	i_size = i_size_read(inode);

	end_index = i_size >> PAGE_CACHE_SHIFT;

	if (page->index < end_index)
		n_bytes = PAGE_CACHE_SIZE;
	else {
		n_bytes = i_size & (PAGE_CACHE_SIZE - 1);

		if (page->index > end_index || !n_bytes) {
			zero_user_segment(page, 0, PAGE_CACHE_SIZE);
			set_page_writeback(page);
			unlock_page(page);
			end_page_writeback(page);
			return 0;
		}
	}

	if (n_bytes != PAGE_CACHE_SIZE)
		zero_user_segment(page, n_bytes, PAGE_CACHE_SIZE);

	get_page(page);

	buffer = kmap(page);

    /*	n_written = yaffs_wr_file(obj, buffer,
				  page->index << PAGE_CACHE_SHIFT, n_bytes, 0);
    */

    n_written = rawfs_write_file(inode, buffer, n_bytes,
        page->index << PAGE_CACHE_SHIFT);

	kunmap(page);
	set_page_writeback(page);
	unlock_page(page);
	end_page_writeback(page);
	put_page(page);

	return (n_written == n_bytes) ? 0 : -ENOSPC;
}

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;

        f2fs_restore_and_release_control_page(&page);

        if (unlikely(bio->bi_error)) {
            set_page_dirty(page);
            set_bit(AS_EIO, &page->mapping->flags);
            f2fs_stop_checkpoint(sbi);
        }
        end_page_writeback(page);
        dec_page_count(sbi, F2FS_WRITEBACK);
    }

    if (!get_pages(sbi, F2FS_WRITEBACK) &&
            !list_empty(&sbi->cp_wait.task_list))
        wake_up(&sbi->cp_wait);

    bio_put(bio);
}

static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wbc)
{
	int err;
	struct buffer_head *bh, *head;
	int nr_underway = 0;
	int write_op = (1 << BIO_RW_META) | ((wbc->sync_mode == WB_SYNC_ALL ?
			WRITE_SYNC_PLUG : WRITE));

	BUG_ON(!PageLocked(page));
	BUG_ON(!page_has_buffers(page));

	head = page_buffers(page);
	bh = head;

	do {
		if (!buffer_mapped(bh))
			continue;
		/*
		 * If it's a fully non-blocking write attempt and we cannot
		 * lock the buffer then redirty the page.  Note that this can
		 * potentially cause a busy-wait loop from pdflush and kswapd
		 * activity, but those code paths have their own higher-level
		 * throttling.
		 */
		if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
			lock_buffer(bh);
		} else if (!trylock_buffer(bh)) {
			redirty_page_for_writepage(wbc, page);
			continue;
		}
		if (test_clear_buffer_dirty(bh)) {
			mark_buffer_async_write(bh);
		} else {
			unlock_buffer(bh);
		}
	} while ((bh = bh->b_this_page) != head);

	/*
	 * The page and its buffers are protected by PageWriteback(), so we can
	 * drop the bh refcounts early.
	 */
	BUG_ON(PageWriteback(page));
	set_page_writeback(page);

	do {
		struct buffer_head *next = bh->b_this_page;
		if (buffer_async_write(bh)) {
			submit_bh(write_op, bh);
			nr_underway++;
		}
		bh = next;
	} while (bh != head);
	unlock_page(page);

	err = 0;
	if (nr_underway == 0)
		end_page_writeback(page);

	return err;
}

/*
 * We may have stale swap cache pages in memory: notice
 * them here and get rid of the unnecessary final write.
 */
int swap_writepage(struct page *page, struct writeback_control *wbc)
{
	struct bio *bio;
	int ret = 0, rw = WRITE;

	if (try_to_free_swap(page)) {
		unlock_page(page);
		goto out;
	}
	#ifdef CONFIG_FRONTSWAP
    if (frontswap_store(page) == 0) {
            set_page_writeback(page);
            unlock_page(page);
            end_page_writeback(page);
            goto out;
    }
    #endif
	bio = get_swap_bio(GFP_NOIO, page, end_swap_bio_write);
	if (bio == NULL) {
		set_page_dirty(page);
		unlock_page(page);
		ret = -ENOMEM;
		goto out;
	}
	if (wbc->sync_mode == WB_SYNC_ALL)
		rw |= REQ_SYNC;
	count_vm_event(PSWPOUT);
	set_page_writeback(page);
	unlock_page(page);
	submit_bio(rw, bio);
out:
	return ret;
}

/*
 * I/O completion handler for multipage BIOs.
 *
 * The mpage code never puts partial pages into a BIO (except for end-of-file).
 * If a page does not map to a contiguous run of blocks then it simply falls
 * back to block_read_full_page().
 *
 * Why is this?  If a page's completion depends on a number of different BIOs
 * which can complete in any order (or at the same time) then determining the
 * status of that page is hard.  See end_buffer_async_read() for the details.
 * There is no point in duplicating all that complexity.
 */
static void mpage_end_io(struct bio *bio, int err)
{
	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
	struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;

	do {
		struct page *page = bvec->bv_page;

		if (--bvec >= bio->bi_io_vec)
			prefetchw(&bvec->bv_page->flags);
		if (bio_data_dir(bio) == READ) {
			if (uptodate) {
				SetPageUptodate(page);
			} else {
				ClearPageUptodate(page);
				SetPageError(page);
			}
			unlock_page(page);
		} else { /* bio_data_dir(bio) == WRITE */
			if (!uptodate) {
				SetPageError(page);
				if (page->mapping)
					set_bit(AS_EIO, &page->mapping->flags);
			}
			end_page_writeback(page);
		}
	} while (bvec >= bio->bi_io_vec);
	bio_put(bio);
}

static void ext4_finish_bio(struct bio *bio)
{
	int i;
	struct bio_vec *bvec;

	bio_for_each_segment_all(bvec, bio, i) {
		struct page *page = bvec->bv_page;
#ifdef CONFIG_EXT4_FS_ENCRYPTION
		struct page *data_page = NULL;
#endif
		struct buffer_head *bh, *head;
		unsigned bio_start = bvec->bv_offset;
		unsigned bio_end = bio_start + bvec->bv_len;
		unsigned under_io = 0;
		unsigned long flags;

		if (!page)
			continue;

#ifdef CONFIG_EXT4_FS_ENCRYPTION
		if (!page->mapping) {
			/* The bounce data pages are unmapped. */
			data_page = page;
			fscrypt_pullback_bio_page(&page, false);
		}
#endif

		if (bio->bi_error) {
			SetPageError(page);
			mapping_set_error(page->mapping, -EIO);
		}
		bh = head = page_buffers(page);
		/*
		 * We check all buffers in the page under BH_Uptodate_Lock
		 * to avoid races with other end io clearing async_write flags
		 */
		local_irq_save(flags);
		bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
		do {
			if (bh_offset(bh) < bio_start ||
			    bh_offset(bh) + bh->b_size > bio_end) {
				if (buffer_async_write(bh))
					under_io++;
				continue;
			}
			clear_buffer_async_write(bh);
			if (bio->bi_error)
				buffer_io_error(bh);
		} while ((bh = bh->b_this_page) != head);
		bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
		local_irq_restore(flags);
		if (!under_io) {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
			if (data_page)
				fscrypt_restore_control_page(data_page);
#endif
			end_page_writeback(page);
		}
	}
}

static void put_io_page(struct ext4_io_page *io_page)
{
	if (atomic_dec_and_test(&io_page->p_count)) {
		end_page_writeback(io_page->p_page);
		put_page(io_page->p_page);
		kmem_cache_free(io_page_cachep, io_page);
	}
}

static void nfs_end_page_writeback(struct page *page)
{
	struct inode *inode = page->mapping->host;
	struct nfs_server *nfss = NFS_SERVER(inode);

	end_page_writeback(page);
	if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH)
		clear_bdi_congested(&nfss->backing_dev_info, BLK_RW_ASYNC);
}

static void writeseg_end_io(struct bio *bio)
{
	struct bio_vec *bvec;
	int i;
	struct super_block *sb = bio->bi_private;
	struct logfs_super *super = logfs_super(sb);

	BUG_ON(bio->bi_error); /* FIXME: Retry io or write elsewhere */

	bio_for_each_segment_all(bvec, bio, i) {
		end_page_writeback(bvec->bv_page);
		page_cache_release(bvec->bv_page);
	}

/**
 * ecryptfs_writepage_complete
 * @page_crypt_req: The encrypt page request that completed
 *
 * Calls when the requested page has been encrypted and written to the lower
 * file system.
 */
static void ecryptfs_writepage_complete(
		struct ecryptfs_page_crypt_req *page_crypt_req)
{
	struct page *page = page_crypt_req->page;
	int rc;
	rc = atomic_read(&page_crypt_req->rc);
	if (unlikely(rc)) {
		ecryptfs_printk(KERN_WARNING, "Error encrypting "
				"page (upper index [0x%.16lx])\n", page->index);
		ClearPageUptodate(page);
		SetPageError(page);
	} else {
		SetPageUptodate(page);
	}
	end_page_writeback(page);
	ecryptfs_free_page_crypt_req(page_crypt_req);
}

static void ext4_finish_bio(struct bio *bio)
{
	int i;
	int error = !test_bit(BIO_UPTODATE, &bio->bi_flags);
	struct bio_vec *bvec;

	bio_for_each_segment_all(bvec, bio, i) {
		struct page *page = bvec->bv_page;
		struct buffer_head *bh, *head;
		unsigned bio_start = bvec->bv_offset;
		unsigned bio_end = bio_start + bvec->bv_len;
		unsigned under_io = 0;
		unsigned long flags;

		if (!page)
			continue;

		if (error) {
			SetPageError(page);
			set_bit(AS_EIO, &page->mapping->flags);
		}
		bh = head = page_buffers(page);
		/*
		 * We check all buffers in the page under BH_Uptodate_Lock
		 * to avoid races with other end io clearing async_write flags
		 */
		local_irq_save(flags);
		bit_spin_lock(BH_Uptodate_Lock, &head->b_state);
		do {
			if (bh_offset(bh) < bio_start ||
			    bh_offset(bh) + bh->b_size > bio_end) {
				if (buffer_async_write(bh))
					under_io++;
				continue;
			}
			clear_buffer_async_write(bh);
			if (error)
				buffer_io_error(bh);
		} while ((bh = bh->b_this_page) != head);
		bit_spin_unlock(BH_Uptodate_Lock, &head->b_state);
		local_irq_restore(flags);
		if (!under_io)
			end_page_writeback(page);
	}
}

static void mpage_end_io_write(struct bio *bio, int err)
{
	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
	struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;

	do {
		struct page *page = bvec->bv_page;

		if (--bvec >= bio->bi_io_vec)
			prefetchw(&bvec->bv_page->flags);

		if (!uptodate){
			if (page->mapping)
				set_bit(AS_EIO, &page->mapping->flags);
		}
		end_page_writeback(page);
	} while (bvec >= bio->bi_io_vec);
	bio_put(bio);
}

static void writeseg_end_io(struct bio *bio, int err)
{
	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
	struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
	struct super_block *sb = bio->bi_private;
	struct logfs_super *super = logfs_super(sb);
	struct page *page;

	BUG_ON(!uptodate); /* FIXME: Retry io or write elsewhere */
	BUG_ON(err);
	BUG_ON(bio->bi_vcnt == 0);
	do {
		page = bvec->bv_page;
		if (--bvec >= bio->bi_io_vec)
			prefetchw(&bvec->bv_page->flags);

		end_page_writeback(page);
		page_cache_release(page);
	} while (bvec >= bio->bi_io_vec);
	bio_put(bio);
	if (atomic_dec_and_test(&super->s_pending_writes))
		wake_up(&wq);
}

/*
 * kill all the pages in the given range
 */
static void afs_kill_pages(struct address_space *mapping,
			   pgoff_t first, pgoff_t last)
{
	struct afs_vnode *vnode = AFS_FS_I(mapping->host);
	struct pagevec pv;
	unsigned count, loop;

	_enter("{%x:%u},%lx-%lx",
	       vnode->fid.vid, vnode->fid.vnode, first, last);

	pagevec_init(&pv);

	do {
		_debug("kill %lx-%lx", first, last);

		count = last - first + 1;
		if (count > PAGEVEC_SIZE)
			count = PAGEVEC_SIZE;
		pv.nr = find_get_pages_contig(mapping, first, count, pv.pages);
		ASSERTCMP(pv.nr, ==, count);

		for (loop = 0; loop < count; loop++) {
			struct page *page = pv.pages[loop];
			ClearPageUptodate(page);
			SetPageError(page);
			end_page_writeback(page);
			if (page->index >= first)
				first = page->index + 1;
			lock_page(page);
			generic_error_remove_page(mapping, page);
		}

		__pagevec_release(&pv);
	} while (first <= last);

	_leave("");
}

/*
 * Redirty all the pages in a given range.
 */
static void afs_redirty_pages(struct writeback_control *wbc,
			      struct address_space *mapping,
			      pgoff_t first, pgoff_t last)
{
	struct afs_vnode *vnode = AFS_FS_I(mapping->host);
	struct pagevec pv;
	unsigned count, loop;

	_enter("{%x:%u},%lx-%lx",
	       vnode->fid.vid, vnode->fid.vnode, first, last);

	pagevec_init(&pv);

	do {
		_debug("redirty %lx-%lx", first, last);

		count = last - first + 1;
		if (count > PAGEVEC_SIZE)
			count = PAGEVEC_SIZE;
		pv.nr = find_get_pages_contig(mapping, first, count, pv.pages);
		ASSERTCMP(pv.nr, ==, count);

		for (loop = 0; loop < count; loop++) {
			struct page *page = pv.pages[loop];

			redirty_page_for_writepage(wbc, page);
			end_page_writeback(page);
			if (page->index >= first)
				first = page->index + 1;
		}

		__pagevec_release(&pv);
	} while (first <= last);

	_leave("");
}

void end_swap_bio_write(struct bio *bio)
{
	struct page *page = bio->bi_io_vec[0].bv_page;

	if (bio->bi_error) {
		SetPageError(page);
		/*
		 * We failed to write the page out to swap-space.
		 * Re-dirty the page in order to avoid it being reclaimed.
		 * Also print a dire warning that things will go BAD (tm)
		 * very quickly.
		 *
		 * Also clear PG_reclaim to avoid rotate_reclaimable_page()
		 */
		set_page_dirty(page);
		pr_alert("Write-error on swap-device (%u:%u:%llu)\n",
			 imajor(bio->bi_bdev->bd_inode),
			 iminor(bio->bi_bdev->bd_inode),
			 (unsigned long long)bio->bi_iter.bi_sector);
		ClearPageReclaim(page);
	}
	end_page_writeback(page);
	bio_put(bio);
}

//.........这里部分代码省略.........
		}
		/* Skip the mft record if it is a base inode. */
		if (!m->base_mft_record) {
			ntfs_debug("Mft record 0x%lx is a base record, "
					"continuing search.", mft_no);
			continue;
		}
		/*
		 * This is an extent mft record.  Check if the inode
		 * corresponding to its base mft record is in icache.
		 */
		na.mft_no = MREF_LE(m->base_mft_record);
		ntfs_debug("Mft record 0x%lx is an extent record.  Looking "
				"for base inode 0x%lx in icache.", mft_no,
				na.mft_no);
		vi = ilookup5(sb, na.mft_no, (test_t)ntfs_test_inode,
				&na);
		if (!vi) {
			/*
			 * The base inode is not in icache.  Skip this extent
			 * mft record.
			 */
			ntfs_debug("Base inode 0x%lx is not in icache, "
					"continuing search.", na.mft_no);
			continue;
		}
		ntfs_debug("Base inode 0x%lx is in icache.", na.mft_no);
		/*
		 * The base inode is in icache.  Check if it has the extent
		 * inode corresponding to this extent mft record attached.
		 */
		ni = NTFS_I(vi);
		down(&ni->extent_lock);
		if (ni->nr_extents <= 0) {
			/*
			 * The base inode has no attached extent inodes.  Skip
			 * this extent mft record.
			 */
			up(&ni->extent_lock);
			iput(vi);
			continue;
		}
		/* Iterate over the attached extent inodes. */
		extent_nis = ni->ext.extent_ntfs_inos;
		for (eni = NULL, j = 0; j < ni->nr_extents; ++j) {
			if (mft_no == extent_nis[j]->mft_no) {
				/*
				 * Found the extent inode corresponding to this
				 * extent mft record.
				 */
				eni = extent_nis[j];
				break;
			}
		}
		/*
		 * If the extent inode was not attached to the base inode, skip
		 * this extent mft record.
		 */
		if (!eni) {
			up(&ni->extent_lock);
			iput(vi);
			continue;
		}
		/*
		 * Found the extent inode corrsponding to this extent mft
		 * record.  If it is dirty, no need to search further.
		 */
		if (NInoDirty(eni)) {
			up(&ni->extent_lock);
			iput(vi);
			is_dirty = TRUE;
			break;
		}
		/* The extent inode is not dirty, so do the next record. */
		up(&ni->extent_lock);
		iput(vi);
	}
	kunmap(page);
	/* If a dirty mft record was found, redirty the page. */
	if (is_dirty) {
		ntfs_debug("Inode 0x%lx is dirty.  Redirtying the page "
				"starting at inode 0x%lx.", mft_no,
				page->index << (PAGE_CACHE_SHIFT -
				vol->mft_record_size_bits));
		redirty_page_for_writepage(wbc, page);
		unlock_page(page);
	} else {
		/*
		 * Keep the VM happy.  This must be done otherwise the
		 * radix-tree tag PAGECACHE_TAG_DIRTY remains set even though
		 * the page is clean.
		 */
		BUG_ON(PageWriteback(page));
		set_page_writeback(page);
		unlock_page(page);
		end_page_writeback(page);
	}
	ntfs_debug("Done.");
	return 0;
}