ovl: store real inode pointer in ->i_private
To get from overlay inode to real inode we currently use 'struct
ovl_entry', which has lifetime connected to overlay dentry. This is okay,
since each overlay dentry had a new overlay inode allocated.
Following patch will break that assumption, so need to leave out ovl_entry.
This patch stores the real inode directly in i_private, with the lowest bit
used to indicate whether the inode is upper or lower.
Lifetime rules remain, using ovl_inode_real() must only be done while
caller holds ref on overlay dentry (and hence on real dentry), or within
RCU protected regions.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 80aa6f1..54e5d66 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -292,6 +292,7 @@
goto out_cleanup;
ovl_dentry_update(dentry, newdentry);
+ ovl_inode_update(d_inode(dentry), d_inode(newdentry));
newdentry = NULL;
/*