Catch filesystems lacking s_bdi
noop_backing_dev_info is used only as a flag to mark filesystems that
don't have any backing store, like tmpfs, procfs, spufs, etc.
Signed-off-by: Joern Engel <joern@logfs.org>
Changed the BUG_ON() to a WARN_ON(). Note that adding dirty inodes
to the noop_backing_dev_info is not legal and will not result in
them being flushed, but we already catch this condition in
__mark_inode_dirty() when checking for a registered bdi.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index e19c677..bd0e3c6 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -247,6 +247,7 @@
#endif
extern struct backing_dev_info default_backing_dev_info;
+extern struct backing_dev_info noop_backing_dev_info;
void default_unplug_io_fn(struct backing_dev_info *bdi, struct page *page);
int writeback_in_progress(struct backing_dev_info *bdi);