writeback: make bdi_start_background_writeback() take bdi_writeback instead of backing_dev_info

}

/**

 * bdi_start_background_writeback - start background writeback

 * @bdi: the backing device to write from

 * wb_start_background_writeback - start background writeback

 * @wb: bdi_writback to write from

 *

 * Description:

 *   This makes sure WB_SYNC_NONE background writeback happens. When

 *   this function returns, it is only guaranteed that for given BDI

 *   this function returns, it is only guaranteed that for given wb

 *   some IO is happening if we are over background dirty threshold.

 *   Caller need not hold sb s_umount semaphore.

 */

void bdi_start_background_writeback(struct backing_dev_info *bdi)

void wb_start_background_writeback(struct bdi_writeback *wb)

{

	/*

	 * We just wake up the flusher thread. It will perform background

	 * writeback as soon as there is no other work to do.

	 */

	trace_writeback_wake_background(bdi);

	wb_wakeup(&bdi->wb);

	trace_writeback_wake_background(wb->bdi);

	wb_wakeup(wb);

}

/*

int __must_check bdi_setup_and_register(struct backing_dev_info *, char *);

void wb_start_writeback(struct bdi_writeback *wb, long nr_pages,

			bool range_cyclic, enum wb_reason reason);

void bdi_start_background_writeback(struct backing_dev_info *bdi);

void wb_start_background_writeback(struct bdi_writeback *wb);

void wb_workfn(struct work_struct *work);

void wb_wakeup_delayed(struct bdi_writeback *wb);

		}

		if (unlikely(!writeback_in_progress(wb)))

			bdi_start_background_writeback(bdi);

			wb_start_background_writeback(wb);

		if (!strictlimit)

			wb_dirty_limits(wb, dirty_thresh, background_thresh,

		return;

	if (nr_reclaimable > background_thresh)

		bdi_start_background_writeback(bdi);

		wb_start_background_writeback(wb);

}

static DEFINE_PER_CPU(int, bdp_ratelimits);