take RCU-dependent stuff around exec_permission() into a new helper

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/namei.c b/fs/namei.c
index 1d6bc8151553729cffa645ef79e06e17b9e5691e..8c704465f6cede349656a8db9ba15757a55e7525 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1322,6 +1322,18 @@ fail:
        return PTR_ERR(dentry);
 }
 
+static inline int may_lookup(struct nameidata *nd)
+{
+       if (nd->flags & LOOKUP_RCU) {
+               int err = exec_permission(nd->inode, IPERM_FLAG_RCU);
+               if (err != -ECHILD)
+                       return err;
+               if (nameidata_drop_rcu(nd))
+                       return -ECHILD;
+       }
+       return exec_permission(nd->inode, 0);
+}
+
 /*
  * Name resolution.
  * This is the basic name resolution function, turning a pathname into
@@ -1352,17 +1364,8 @@ static int link_path_walk(const char *name, struct nameidata *nd)
                unsigned int c;
 
                nd->flags |= LOOKUP_CONTINUE;
-               if (nd->flags & LOOKUP_RCU) {
-                       err = exec_permission(nd->inode, IPERM_FLAG_RCU);
-                       if (err == -ECHILD) {
-                               if (nameidata_drop_rcu(nd))
-                                       return -ECHILD;
-                               goto exec_again;
-                       }
-               } else {
-exec_again:
-                       err = exec_permission(nd->inode, 0);
-               }
+
+               err = may_lookup(nd);
                if (err)
                        break;