ovl: separate detection of remote upper layer from stacked overlay

Following patch will allow remote as upper layer, but not overlay stacked
on upper layer.  Separate the two concepts.

This patch is doesn't change behavior.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

diff --git a/fs/overlayfs/namei.c b/fs/overlayfs/namei.c
index ed9e129..a5b998a 100644 (file)
--- a/fs/overlayfs/namei.c
+++ b/fs/overlayfs/namei.c
@@ -845,7 +845,8 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
                if (err)
                        goto out;
 
-               if (upperdentry && unlikely(ovl_dentry_remote(upperdentry))) {
+               if (upperdentry && (upperdentry->d_flags & DCACHE_OP_REAL ||
+                                   unlikely(ovl_dentry_remote(upperdentry)))) {
                        dput(upperdentry);
                        err = -EREMOTE;
                        goto out;

diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index a05bf11..bc35cd6 100644 (file)
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -752,13 +752,13 @@ static int ovl_mount_dir(const char *name, struct path *path)
                ovl_unescape(tmp);
                err = ovl_mount_dir_noesc(tmp, path);
 
-               if (!err)
-                       if (ovl_dentry_remote(path->dentry)) {
-                               pr_err("filesystem on '%s' not supported as upperdir\n",
-                                      tmp);
-                               path_put_init(path);
-                               err = -EINVAL;
-                       }
+               if (!err && (ovl_dentry_remote(path->dentry) ||
+                            path->dentry->d_flags & DCACHE_OP_REAL)) {
+                       pr_err("filesystem on '%s' not supported as upperdir\n",
+                              tmp);
+                       path_put_init(path);
+                       err = -EINVAL;
+               }
                kfree(tmp);
        }
        return err;

diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index f318e48..997c315 100644 (file)
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -93,8 +93,7 @@ struct ovl_entry *ovl_alloc_entry(unsigned int numlower)
 bool ovl_dentry_remote(struct dentry *dentry)
 {
        return dentry->d_flags &
-               (DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE |
-                DCACHE_OP_REAL);
+               (DCACHE_OP_REVALIDATE | DCACHE_OP_WEAK_REVALIDATE);
 }
 
 bool ovl_dentry_weird(struct dentry *dentry)