linux-imx

config OVERLAY_FS

    tristate "Overlay filesystem support"

    select EXPORTFS

    help

      An overlay filesystem combines two filesystems - an 'upper' filesystem

      and a 'lower' filesystem.  When a name exists in both filesystems, the

      object in the 'upper' filesystem is visible while the object in the

      'lower' filesystem is either hidden or, in the case of directories,

      merged with the 'upper' object.

​

      For more information see Documentation/filesystems/overlayfs.txt

​

config OVERLAY_FS_REDIRECT_DIR

    bool "Overlayfs: turn on redirect directory 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.

​

      If unsure, say N.

​

config OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW

    bool "Overlayfs: follow redirects even if redirects are turned off"

    default y

    depends on OVERLAY_FS

    help

      Disable this to get a possibly more secure configuration, but that

      might not be backward compatible with previous kernels.

​

      If backward compatibility is not an issue, then it is safe and

      recommended to say N here.

​

      For more information, see Documentation/filesystems/overlayfs.txt

​

      If unsure, say Y.

​

config OVERLAY_FS_INDEX

    bool "Overlayfs: turn on inodes index feature by default"

    depends on OVERLAY_FS

    help

      If this config option is enabled then overlay filesystems will use

      the index directory to map lower inodes to upper inodes by default.

      In this case it is still possible to turn off index globally with the

      "index=off" module option or on a filesystem instance basis with the

      "index=off" mount option.

​

      The inodes index feature prevents breaking of lower hardlinks on copy

      up.

​

      Note, that the inodes index feature is not backward compatible.

      That is, mounting an overlay which has an inodes index on a kernel

      that doesn't support this feature will have unexpected results.

​

      If unsure, say N.

​

config OVERLAY_FS_NFS_EXPORT