x86: merge getuser asm functions.

getuser_32.S and getuser_64.S are merged into getuser.S.

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 104 insertions, 0 deletions

diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S
new file mode 100644
index 000000000000..ad374003742f
--- /dev/null
+++ b/arch/x86/lib/getuser.S
@@ -0,0 +1,104 @@
+/*
+ * __get_user functions.
+ *
+ * (C) Copyright 1998 Linus Torvalds
+ * (C) Copyright 2005 Andi Kleen
+ * (C) Copyright 2008 Glauber Costa
+ *
+ * These functions have a non-standard call interface
+ * to make them more efficient, especially as they
+ * return an error value in addition to the "real"
+ * return value.
+ */
+
+/*
+ * __get_user_X
+ *
+ * Inputs:	%[r|e]ax contains the address.
+ *		The register is modified, but all changes are undone
+ *		before returning because the C code doesn't know about it.
+ *
+ * Outputs:	%[r|e]ax is error code (0 or -EFAULT)
+ *		%[r|e]dx contains zero-extended value
+ *
+ *
+ * These functions should not modify any other registers,
+ * as they get called from within inline assembly.
+ */
+
+#include <linux/linkage.h>
+#include <asm/dwarf2.h>
+#include <asm/page.h>
+#include <asm/errno.h>
+#include <asm/asm-offsets.h>
+#include <asm/thread_info.h>
+#include <asm/asm.h>
+
+	.text
+ENTRY(__get_user_1)
+	CFI_STARTPROC
+	GET_THREAD_INFO(%_ASM_DX)
+	cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
+	jae bad_get_user
+1:	movzb (%_ASM_AX),%edx
+	xor %eax,%eax
+	ret
+	CFI_ENDPROC
+ENDPROC(__get_user_1)
+
+ENTRY(__get_user_2)
+	CFI_STARTPROC
+	add $1,%_ASM_AX
+	jc bad_get_user
+	GET_THREAD_INFO(%_ASM_DX)
+	cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
+	jae bad_get_user
+2:	movzwl -1(%_ASM_AX),%edx
+	xor %eax,%eax
+	ret
+	CFI_ENDPROC
+ENDPROC(__get_user_2)
+
+ENTRY(__get_user_4)
+	CFI_STARTPROC
+	add $3,%_ASM_AX
+	jc bad_get_user
+	GET_THREAD_INFO(%_ASM_DX)
+	cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
+	jae bad_get_user
+3:	mov -3(%_ASM_AX),%edx
+	xor %eax,%eax
+	ret
+	CFI_ENDPROC
+ENDPROC(__get_user_4)
+
+#ifdef CONFIG_X86_64
+ENTRY(__get_user_8)
+	CFI_STARTPROC
+	add $7,%_ASM_AX
+	jc bad_get_user
+	GET_THREAD_INFO(%_ASM_DX)
+	cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
+	jae	bad_get_user
+4:	movq -7(%_ASM_AX),%_ASM_DX
+	xor %eax,%eax
+	ret
+	CFI_ENDPROC
+ENDPROC(__get_user_8)
+#endif
+
+bad_get_user:
+	CFI_STARTPROC
+	xor %edx,%edx
+	mov $(-EFAULT),%_ASM_AX
+	ret
+	CFI_ENDPROC
+END(bad_get_user)
+
+.section __ex_table,"a"
+	_ASM_PTR 1b,bad_get_user
+	_ASM_PTR 2b,bad_get_user
+	_ASM_PTR 3b,bad_get_user
+#ifdef CONFIG_X86_64
+	_ASM_PTR 4b,bad_get_user
+#endif