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-rw-r--r--arch/x86/boot/copy.S65
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/x86/boot/copy.S b/arch/x86/boot/copy.S
new file mode 100644
index 000000000..6afd05e81
--- /dev/null
+++ b/arch/x86/boot/copy.S
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* ----------------------------------------------------------------------- *
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright 2007 rPath, Inc. - All Rights Reserved
+ *
+ * ----------------------------------------------------------------------- */
+
+#include <linux/linkage.h>
+
+/*
+ * Memory copy routines
+ */
+
+ .code16
+ .text
+
+SYM_FUNC_START_NOALIGN(memcpy)
+ pushw %si
+ pushw %di
+ movw %ax, %di
+ movw %dx, %si
+ pushw %cx
+ shrw $2, %cx
+ rep; movsl
+ popw %cx
+ andw $3, %cx
+ rep; movsb
+ popw %di
+ popw %si
+ retl
+SYM_FUNC_END(memcpy)
+
+SYM_FUNC_START_NOALIGN(memset)
+ pushw %di
+ movw %ax, %di
+ movzbl %dl, %eax
+ imull $0x01010101,%eax
+ pushw %cx
+ shrw $2, %cx
+ rep; stosl
+ popw %cx
+ andw $3, %cx
+ rep; stosb
+ popw %di
+ retl
+SYM_FUNC_END(memset)
+
+SYM_FUNC_START_NOALIGN(copy_from_fs)
+ pushw %ds
+ pushw %fs
+ popw %ds
+ calll memcpy
+ popw %ds
+ retl
+SYM_FUNC_END(copy_from_fs)
+
+SYM_FUNC_START_NOALIGN(copy_to_fs)
+ pushw %es
+ pushw %fs
+ popw %es
+ calll memcpy
+ popw %es
+ retl
+SYM_FUNC_END(copy_to_fs)