path: root/fs/f2fs/data.c

/*
 * 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/aio.h>
#include <linux/writeback.h>
#include <linux/backing-dev.h>
#include <linux/blkdev.h>
#include <linux/bio.h>
#include <linux/prefetch.h>

#include "f2fs.h"
#include "node.h"
#include "segment.h"
#include <trace/events/f2fs.h>

/*
 * Low-level block read/write IO operations.
 */
static struct bio *__bio_alloc(struct block_device *bdev, int npages)
{
	struct bio *bio;

	/* No failure on bio allocation */
	bio = bio_alloc(GFP_NOIO, npages);
	bio->bi_bdev = bdev;
	bio->bi_private = NULL;
	return bio;
}

static void f2fs_read_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 (unlikely(!uptodate)) {
			ClearPageUptodate(page);
			SetPageError(page);
		} else {
			SetPageUptodate(page);
		}
		unlock_page(page);
	} while (bvec >= bio->bi_io_vec);

	bio_put(bio);
}

static void f2fs_write_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 f2fs_sb_info *sbi = F2FS_SB(bvec->bv_page->mapping->host->i_sb);

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

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

		if (unlikely(!uptodate)) {
			SetPageError(page);
			set_bit(AS_EIO, &page->mapping->flags);
			set_ckpt_flags(sbi->ckpt, CP_ERROR_FLAG);
			sbi->sb->s_flags |= MS_RDONLY;
		}
		end_page_writeback(page);
		dec_page_count(sbi, F2FS_WRITEBACK);
	} while (bvec >= bio->bi_io_vec);

	if (bio->bi_private)
		complete(bio->bi_private);

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

	bio_put(bio);
}

static void __submit_merged_bio(struct f2fs_sb_info *sbi,
				struct f2fs_bio_info *io,
				enum page_type type, bool sync, int rw)
{
	enum page_type btype = PAGE_TYPE_OF_BIO(type);

	if (!io->bio)
		return;

	if (btype == META)
		rw |= REQ_META;

	if (is_read_io(rw)) {
		if (sync)
			rw |= READ_SYNC;
		submit_bio(rw, io->bio);
		trace_f2fs_submit_read_bio(sbi->sb, rw, type, io->bio);
		io->bio = NULL;
		return;
	}

	if (sync)
		rw |= WRITE_SYNC;
	if (type >= META_FLUSH)
		rw |= WRITE_FLUSH_FUA;

	/*
	 * META_FLUSH is only from the checkpoint procedure, and we should wait
	 * this metadata bio for FS consistency.
	 */
	if (type == META_FLUSH) {
		DECLARE_COMPLETION_ONSTACK(wait);
		io->bio->bi_private = &wait;
		submit_bio(rw, io->bio);
		wait_for_completion(&wait);
	} else {
		submit_bio(rw, io->bio);
	}
	trace_f2fs_submit_write_bio(sbi->sb, rw, btype, io->bio);
	io->bio = NULL;
}

void f2fs_submit_merged_bio(struct f2fs_sb_info *sbi,
				enum page_type type, bool sync, int rw)
{
	enum page_type btype = PAGE_TYPE_OF_BIO(type);
	struct f2fs_bio_info *io;

	io = is_read_io(rw) ? &sbi->read_io : &sbi->write_io[btype];

	mutex_lock(&io->io_mutex);
	__submit_merged_bio(sbi, io, type, sync, rw);
	mutex_unlock(&io->io_mutex);
}

/*
 * Fil