f2fs: add to account direct IO

This patch adds f2fs_dio_submit_bio() to hook submit_io/end_io functions
in direct IO path, in order to account DIO.

Later, we will add this count into is_idle() to let background GC/Discard
thread be aware of DIO.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 50 insertions, 1 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index b293cb3e27a2..1d15535e3b42 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -2548,6 +2548,53 @@ static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
 	return 0;
 }
 
+static void f2fs_dio_end_io(struct bio *bio)
+{
+	struct f2fs_private_dio *dio = bio->bi_private;
+
+	dec_page_count(F2FS_I_SB(dio->inode),
+			dio->write ? F2FS_DIO_WRITE : F2FS_DIO_READ);
+
+	bio->bi_private = dio->orig_private;
+	bio->bi_end_io = dio->orig_end_io;
+
+	kfree(dio);
+
+	bio_endio(bio);
+}
+
+static void f2fs_dio_submit_bio(struct bio *bio, struct inode *inode,
+							loff_t file_offset)
+{
+	struct f2fs_private_dio *dio;
+	bool write = (bio_op(bio) == REQ_OP_WRITE);
+	int err;
+
+	dio = f2fs_kzalloc(F2FS_I_SB(inode),
+			sizeof(struct f2fs_private_dio), GFP_NOFS);
+	if (!dio) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	dio->inode = inode;
+	dio->orig_end_io = bio->bi_end_io;
+	dio->orig_private = bio->bi_private;
+	dio->write = write;
+
+	bio->bi_end_io = f2fs_dio_end_io;
+	bio->bi_private = dio;
+
+	inc_page_count(F2FS_I_SB(inode),
+			write ? F2FS_DIO_WRITE : F2FS_DIO_READ);
+
+	submit_bio(bio);
+	return;
+out:
+	bio->bi_status = BLK_STS_IOERR;
+	bio_endio(bio);
+}
+
 static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 {
 	struct address_space *mapping = iocb->ki_filp->f_mapping;
@@ -2594,7 +2641,9 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 			down_read(&fi->i_gc_rwsem[READ]);
 	}
 
-	err = blockdev_direct_IO(iocb, inode, iter, get_data_block_dio);
+	err = __blockdev_direct_IO(iocb, inode, inode->i_sb->s_bdev,
+			iter, get_data_block_dio, NULL, f2fs_dio_submit_bio,
+			DIO_LOCKING | DIO_SKIP_HOLES);
 
 	if (do_opu)
 		up_read(&fi->i_gc_rwsem[READ]);