ovl: store layer index in ovl_layer

Store the fs root layer index inside ovl_layer struct, so we can
get the root fs layer index from merge dir lower layer instead of
find it with ovl_find_layer() helper.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index 69f4f19659fc53ef6d73399e37aa4fa272720271..a38db76cbccd8efcdf2184d1a262caef310c733f 100644 (file)
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -572,18 +572,6 @@ int ovl_path_next(int idx, struct dentry *dentry, struct path *path)
        return (idx < oe->numlower) ? idx + 1 : -1;
 }
 
-static int ovl_find_layer(struct ovl_fs *ofs, struct ovl_path *path)
-{
-       int i;
-
-       for (i = 0; i < ofs->numlower; i++) {
-               if (ofs->lower_layers[i].mnt == path->layer->mnt)
-                       break;
-       }
-
-       return i;
-}
-
 /* Fix missing 'origin' xattr */
 static int ovl_fix_origin(struct dentry *dentry, struct dentry *lower,
                          struct dentry *upper)
@@ -733,11 +721,8 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
 
                if (d.redirect && d.redirect[0] == '/' && poe != roe) {
                        poe = roe;
-
                        /* Find the current layer on the root dentry */
-                       i = ovl_find_layer(ofs, &lower);
-                       if (WARN_ON(i == ofs->numlower))
-                               break;
+                       i = lower.layer->idx - 1;
                }
        }
 

diff --git a/fs/overlayfs/ovl_entry.h b/fs/overlayfs/ovl_entry.h
index 9d0bc03bf6e4563ef280fe5e8f695cc9f1e8abd5..608e487550708cec32e7a8ea4fe9b743351ab50c 100644 (file)
--- a/fs/overlayfs/ovl_entry.h
+++ b/fs/overlayfs/ovl_entry.h
@@ -22,6 +22,8 @@ struct ovl_config {
 struct ovl_layer {
        struct vfsmount *mnt;
        dev_t pseudo_dev;
+       /* Index of this layer in fs root (upper == 0) */
+       int idx;
 };
 
 struct ovl_path {

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 9aa5d32af427fbf87354d4aabfeb1197e70f03ec..b34a002ab4b57dd2463f0db1e20bbba91d1a0808 100644 (file)
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -1106,6 +1106,7 @@ static int ovl_get_lower_layers(struct ovl_fs *ofs, struct path *stack,
 
                ofs->lower_layers[ofs->numlower].mnt = mnt;
                ofs->lower_layers[ofs->numlower].pseudo_dev = dev;
+               ofs->lower_layers[ofs->numlower].idx = i + 1;
                ofs->numlower++;
 
                /* Check if all lower layers are on same sb */