fs: remove default_backing_dev_info
Now that default_backing_dev_info is not used for writeback purposes we can
git rid of it easily:
- instead of using it's name for tracing unregistered bdi we just use
"unknown"
- btrfs and ceph can just assign the default read ahead window themselves
like several other filesystems already do.
- we can assign noop_backing_dev_info as the default one in alloc_super.
All filesystems already either assigned their own or
noop_backing_dev_info.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/fs/super.c b/fs/super.c
index eae088f..3b4dada 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -185,8 +185,8 @@
}
init_waitqueue_head(&s->s_writers.wait);
init_waitqueue_head(&s->s_writers.wait_unfrozen);
+ s->s_bdi = &noop_backing_dev_info;
s->s_flags = flags;
- s->s_bdi = &default_backing_dev_info;
INIT_HLIST_NODE(&s->s_instances);
INIT_HLIST_BL_HEAD(&s->s_anon);
INIT_LIST_HEAD(&s->s_inodes);
@@ -863,10 +863,7 @@
int set_anon_super(struct super_block *s, void *data)
{
- int error = get_anon_bdev(&s->s_dev);
- if (!error)
- s->s_bdi = &noop_backing_dev_info;
- return error;
+ return get_anon_bdev(&s->s_dev);
}
EXPORT_SYMBOL(set_anon_super);
@@ -1111,7 +1108,6 @@
sb = root->d_sb;
BUG_ON(!sb);
WARN_ON(!sb->s_bdi);
- WARN_ON(sb->s_bdi == &default_backing_dev_info);
sb->s_flags |= MS_BORN;
error = security_sb_kern_mount(sb, flags, secdata);