Merge branch 'next'

1 files changed, 16 insertions, 10 deletions

diff --git a/include/efi_variable.h b/include/efi_variable.h
index 4065cf45eca..c3229c717d8 100644
--- a/include/efi_variable.h
+++ b/include/efi_variable.h
@@ -137,13 +137,11 @@ struct efi_var_file {
 };
 
 /**
- * efi_var_to_file() - save non-volatile variables as file
- *
- * File ubootefi.var is created on the EFI system partion.
+ * efi_var_to_storage() - save non-volatile variables
  *
  * Return:	status code
  */
-efi_status_t efi_var_to_file(void);
+efi_status_t efi_var_to_storage(void);
 
 /**
  * efi_var_collect() - collect variables in buffer
@@ -161,6 +159,11 @@ efi_status_t efi_var_to_file(void);
 efi_status_t __maybe_unused efi_var_collect(struct efi_var_file **bufp, loff_t *lenp,
 					    u32 check_attr_mask);
 
+/* GUID used by Shim to store the MOK database */
+#define SHIM_LOCK_GUID \
+	EFI_GUID(0x605dab50, 0xe046, 0x4300, \
+		 0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, 0x23)
+
 /**
  * efi_var_restore() - restore EFI variables from buffer
  *
@@ -173,17 +176,14 @@ efi_status_t __maybe_unused efi_var_collect(struct efi_var_file **bufp, loff_t *
 efi_status_t efi_var_restore(struct efi_var_file *buf, bool safe);
 
 /**
- * efi_var_from_file() - read variables from file
- *
- * File ubootefi.var is read from the EFI system partitions and the variables
- * stored in the file are created.
+ * efi_var_from_storage() - read variables
  *
  * In case the file does not exist yet or a variable cannot be set EFI_SUCCESS
  * is returned.
  *
  * Return:	status code
  */
-efi_status_t efi_var_from_file(void);
+efi_status_t efi_var_from_storage(void);
 
 /**
  * efi_var_mem_init() - set-up variable list
@@ -216,6 +216,11 @@ void efi_var_mem_del(struct efi_var_entry *var);
  * The variable is appended without checking if a variable of the same name
  * already exists. The two data buffers are concatenated.
  *
+ * When @changep is non-NULL and @size2 is 0, the function compares the new
+ * value against an existing variable with the same name and vendor. If
+ * attributes and data are identical the insertion is skipped and *@changep
+ * is set to false, avoiding superfluous writes.
+ *
  * @variable_name:	variable name
  * @vendor:		GUID
  * @attributes:		variable attributes
@@ -224,13 +229,14 @@ void efi_var_mem_del(struct efi_var_entry *var);
  * @size2:		size of the second data field
  * @data2:		second data buffer
  * @time:		time of authentication (as seconds since start of epoch)
+ * @changep:		pointer to change flag (may be NULL)
  * Result:		status code
  */
 efi_status_t efi_var_mem_ins(const u16 *variable_name,
 			     const efi_guid_t *vendor, u32 attributes,
 			     const efi_uintn_t size1, const void *data1,
 			     const efi_uintn_t size2, const void *data2,
-			     const u64 time);
+			     const u64 time, bool *changep);
 
 /**
  * efi_var_mem_free() - determine free memory for variables