ovl: Store lower data inode in ovl_inode
Right now ovl_inode stores inode pointer for lower inode. This helps with
quickly getting lower inode given overlay inode (ovl_inode_lower()).
Now with metadata only copy-up, we can have metacopy inode in middle layer
as well and inode containing data can be different from ->lower. I need to
be able to open the real file in ovl_open_realfile() and for that I need to
quickly find the lower data inode.
Hence store lower data inode also in ovl_inode. Also provide an helper
ovl_inode_lowerdata() to access this field.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index ea4134e..ec23703 100644
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -89,7 +89,10 @@ static inline struct ovl_entry *OVL_E(struct dentry *dentry)
}
struct ovl_inode {
- struct ovl_dir_cache *cache;
+ union {
+ struct ovl_dir_cache *cache; /* directory */
+ struct inode *lowerdata; /* regular file */
+ };
const char *redirect;
u64 version;
unsigned long flags;