Commit 688ea0e5 authored by Miklos Szeredi's avatar Miklos Szeredi
Browse files

ovl: allow redirect_dir to default to "on" 



This patch introduces a kernel config option and a module param.  Both can
be used independently to turn the default value of redirect_dir on or off.

Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent d1595119

fs/overlayfs/Kconfig

+14 −0
Original line number Diff line number Diff line
@@ -8,3 +8,17 @@ config OVERLAY_FS 
	  merged with the 'upper' object.



	  For more information see Documentation/filesystems/overlayfs.txt



config OVERLAY_FS_REDIRECT_DIR

	bool "Overlayfs: turn on redirect dir feature by default"

	depends on OVERLAY_FS

	help

	  If this config option is enabled then overlay filesystems will use

	  redirects when renaming directories by default.  In this case it is

	  still possible to turn off redirects globally with the

	  "redirect_dir=off" module option or on a filesystem instance basis

	  with the "redirect_dir=off" mount option.



	  Note, that redirects are not backward compatible.  That is, mounting

	  an overlay which has redirects on a kernel that doesn't support this

	  feature will have unexpected results.

fs/overlayfs/super.c

+5 −0
Original line number Diff line number Diff line
@@ -28,6 +28,10 @@ struct ovl_dir_cache; 


#define OVL_MAX_STACK 500



static bool ovl_redirect_dir_def = IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_DIR);

module_param_named(redirect_dir, ovl_redirect_dir_def, bool, 0644);

MODULE_PARM_DESC(ovl_redirect_dir_def,

		 "Default to on or off for the redirect_dir feature");



static void ovl_dentry_release(struct dentry *dentry)

{
@@ -702,6 +706,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) 
	if (!ufs)

		goto out;



	ufs->config.redirect_dir = ovl_redirect_dir_def;

	err = ovl_parse_opt((char *) data, &ufs->config);

	if (err)

		goto out_free_config;