writeback: simplify and split bdi_start_writeback

bdi_start_writeback now never gets a superblock passed, so we can just remove
that case.  And to further untangle the code and flatten the call stack
split it into two trivial helpers for it's two callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index aee5f6ce166..9ae2889096b 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -105,8 +105,8 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
 int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev);
 void bdi_unregister(struct backing_dev_info *bdi);
 int bdi_setup_and_register(struct backing_dev_info *, char *, unsigned int);
-void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
-                                long nr_pages);
+void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages);
+void bdi_start_background_writeback(struct backing_dev_info *bdi);
 int bdi_writeback_task(struct bdi_writeback *wb);
 int bdi_has_dirty_io(struct backing_dev_info *bdi);
 void bdi_arm_supers_timer(void);