1 files changed, 87 insertions, 0 deletions
diff --git a/arch/i386/lib/putuser.S b/arch/i386/lib/putuser.S
new file mode 100644
index 0000000..a32d9f5
--- /dev/null
+++ b/arch/i386/lib/putuser.S
@@ -0,0 +1,87 @@
+/*
+ * __put_user functions.
+ *
+ * (C) Copyright 2005 Linus Torvalds
+ *
+ * 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.
+ */
+#include <asm/thread_info.h>
+
+
+/*
+ * __put_user_X
+ *
+ * Inputs:	%eax[:%edx] contains the data
+ *		%ecx contains the address
+ *
+ * Outputs:	%eax is error code (0 or -EFAULT)
+ *
+ * These functions should not modify any other registers,
+ * as they get called from within inline assembly.
+ */
+
+#define ENTER	pushl %ebx ; GET_THREAD_INFO(%ebx)
+#define EXIT	popl %ebx ; ret
+
+.text
+.align 4
+.globl __put_user_1
+__put_user_1:
+	ENTER
+	cmpl TI_addr_limit(%ebx),%ecx
+	jae bad_put_user
+1:	movb %al,(%ecx)
+	xorl %eax,%eax
+	EXIT
+
+.align 4
+.globl __put_user_2
+__put_user_2:
+	ENTER
+	movl TI_addr_limit(%ebx),%ebx
+	subl $1,%ebx
+	cmpl %ebx,%ecx
+	jae bad_put_user
+2:	movw %ax,(%ecx)
+	xorl %eax,%eax
+	EXIT
+
+.align 4
+.globl __put_user_4
+__put_user_4:
+	ENTER
+	movl TI_addr_limit(%ebx),%ebx
+	subl $3,%ebx
+	cmpl %ebx,%ecx
+	jae bad_put_user
+3:	movl %eax,(%ecx)
+	xorl %eax,%eax
+	EXIT
+
+.align 4
+.globl __put_user_8
+__put_user_8:
+	ENTER
+	movl TI_addr_limit(%ebx),%ebx
+	subl $7,%ebx
+	cmpl %ebx,%ecx
+	jae bad_put_user
+4:	movl %eax,(%ecx)
+5:	movl %edx,4(%ecx)
+	xorl %eax,%eax
+	EXIT
+
+bad_put_user:
+	movl $-14,%eax
+	EXIT
+
+.section __ex_table,"a"
+	.long 1b,bad_put_user
+	.long 2b,bad_put_user
+	.long 3b,bad_put_user
+	.long 4b,bad_put_user
+	.long 5b,bad_put_user
+.previous