efivars: Move pstore code into the new EFI directory

efivars.c has grown far too large and needs to be divided up. Create a
new directory and move the persistence storage code to efi-pstore.c now
that it uses the new efivar API. This helps us to greatly reduce the
size of efivars.c and paves the way for moving other code out of
efivars.c.

Note that because CONFIG_EFI_VARS can be built as a module efi-pstore
must also include support for building as a module.

Reviewed-by: Tom Gundersen <teg@jklm.no>
Tested-by: Tom Gundersen <teg@jklm.no>
Cc: Seiji Aguchi <seiji.aguchi@hds.com>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Colin Cross <ccross@android.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
new file mode 100644
index 000000000000..b0fc7c79dfbb
--- /dev/null
+++ b/drivers/firmware/efi/Kconfig
@@ -0,0 +1,39 @@
+menu "EFI (Extensible Firmware Interface) Support"
+        depends on EFI
+
+config EFI_VARS
+        tristate "EFI Variable Support via sysfs"
+        depends on EFI
+        default n
+        help
+          If you say Y here, you are able to get EFI (Extensible Firmware
+          Interface) variable information via sysfs.  You may read,
+          write, create, and destroy EFI variables through this interface.
+
+          Note that using this driver in concert with efibootmgr requires
+          at least test release version 0.5.0-test3 or later, which is
+          available from Matt Domsch's website located at:
+          <http://linux.dell.com/efibootmgr/testing/efibootmgr-0.5.0-test3.tar.gz>
+
+          Subsequent efibootmgr releases may be found at:
+          <http://linux.dell.com/efibootmgr>
+
+config EFI_VARS_PSTORE
+        tristate "Register efivars backend for pstore"
+        depends on EFI_VARS && PSTORE
+        default y
+        help
+          Say Y here to enable use efivars as a backend to pstore. This
+          will allow writing console messages, crash dumps, or anything
+          else supported by pstore to EFI variables.
+
+config EFI_VARS_PSTORE_DEFAULT_DISABLE
+        bool "Disable using efivars as a pstore backend by default"
+        depends on EFI_VARS_PSTORE
+        default n
+        help
+          Saying Y here will disable the use of efivars as a storage
+          backend for pstore by default. This setting can be overridden
+          using the efivars module's pstore_disable parameter.
+
+endmenu