diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c index 52aaa8530710..b599059d6f78 100644 --- a/fs/overlayfs/inode.c +++ b/fs/overlayfs/inode.c @@ -15,6 +15,14 @@ #include #include "overlayfs.h" + +static dev_t ovl_get_pseudo_dev(struct dentry *dentry) +{ + struct ovl_entry *oe = dentry->d_fsdata; + + return oe->lowerstack[0].layer->pseudo_dev; +} + int ovl_setattr(struct dentry *dentry, struct iattr *attr) { int err; @@ -121,6 +129,13 @@ int ovl_getattr(const struct path *path, struct kstat *stat, */ stat->dev = dentry->d_sb->s_dev; stat->ino = dentry->d_inode->i_ino; + } else if (!OVL_TYPE_UPPER(type)) { + /* + * For non-samefs setup, to make sure that st_dev/st_ino pair + * is unique across the system, we use a unique anonymous + * st_dev for lower layer inode. + */ + stat->dev = ovl_get_pseudo_dev(dentry); } /*