Commit c7b50db2 authored by Jan Kara's avatar Jan Kara
Browse files

vfs: Remove syncing from generic_file_direct_write() and generic_file_buffered_write() 



generic_file_direct_write() and generic_file_buffered_write() called
generic_osync_inode() if it was called on O_SYNC file or IS_SYNC inode. But
this is superfluous since generic_file_aio_write() does the syncing as well.
Also XFS and OCFS2 which call these functions directly handle syncing
themselves. So let's have a single place where syncing happens:
generic_file_aio_write().

We slightly change the behavior by syncing only the range of file to which the
write happened for buffered writes but that should be all that is required.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs@oss.sgi.com
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent e4dd9de3

mm/filemap.c

+6 −29
Original line number Diff line number Diff line
@@ -2187,20 +2187,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov, 
		}

		*ppos = end;

	}



	/*

	 * Sync the fs metadata but not the minor inode changes and

	 * of course not the data as we did direct DMA for the IO.

	 * i_mutex is held, which protects generic_osync_inode() from

	 * livelocking.  AIO O_DIRECT ops attempt to sync metadata here.

	 */

out:

	if ((written >= 0 || written == -EIOCBQUEUED) &&

	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {

		int err = generic_osync_inode(inode, mapping, OSYNC_METADATA);

		if (err < 0)

			written = err;

	}

	return written;

}

EXPORT_SYMBOL(generic_file_direct_write);
@@ -2332,8 +2319,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, 
{

	struct file *file = iocb->ki_filp;

	struct address_space *mapping = file->f_mapping;

	const struct address_space_operations *a_ops = mapping->a_ops;

	struct inode *inode = mapping->host;

	ssize_t status;

	struct iov_iter i;
@@ -2343,16 +2328,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, 
	if (likely(status >= 0)) {

		written += status;

		*ppos = pos + status;



		/*

		 * For now, when the user asks for O_SYNC, we'll actually give

		 * O_DSYNC

		 */

		if (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode))) {

			if (!a_ops->writepage || !is_sync_kiocb(iocb))

				status = generic_osync_inode(inode, mapping,

						OSYNC_METADATA|OSYNC_DATA);

		}

  	}

	

	/*
@@ -2514,11 +2489,12 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb, 


	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);



	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {

	if ((ret > 0 || ret == -EIOCBQUEUED) &&

	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {

		ssize_t err;



		err = sync_page_range_nolock(inode, mapping, pos, ret);

		if (err < 0)

		if (err < 0 && ret > 0)

			ret = err;

	}

	return ret;
@@ -2550,11 +2526,12 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov, 
	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);

	mutex_unlock(&inode->i_mutex);



	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {

	if ((ret > 0 || ret == -EIOCBQUEUED) &&

	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {

		ssize_t err;



		err = sync_page_range(inode, mapping, pos, ret);

		if (err < 0)

		if (err < 0 && ret > 0)

			ret = err;

	}

	return ret;

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