btrfs: fix wrong accounting of raid1 data profile in statfs

The sizes that are obtained from space infos are in raw units and have
to be adjusted according to the raid factor. This was missing for
f_bavail and df reported doubled size for raid1.

Reported-by: Martin Steigerwald <Martin@lichtvoll.de>
Fixes: ba7b6e62f420 ("btrfs: adjust statfs calculations according to raid profiles")
CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
(cherry picked from commit 0d95c1bec906dd1ad951c9c001e798ca52baeb0f)

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 96b0be67fad168c4ba799d8fe992d89e2e906fe7..391ec4418460046f80042f40ba98d41b0a7c4ab8 100644 (file)
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1859,7 +1859,7 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
        buf->f_bfree -= block_rsv->size >> bits;
        spin_unlock(&block_rsv->lock);
 
-       buf->f_bavail = total_free_data;
+       buf->f_bavail = div_u64(total_free_data, factor);
        ret = btrfs_calc_avail_data_space(fs_info->tree_root, &total_free_data);
        if (ret)
                return ret;