bitkeeper revision 1.1682 (42a42b05Cvw3LyFcUHH4i1_9HWbLBA)

Merge x86/32 and x86/64 usercopy routines.
Signed-off-by: Keir Fraser <keir@xensource.com>

1 files changed, 139 insertions, 0 deletions

diff --git a/xen/arch/x86/usercopy.c b/xen/arch/x86/usercopy.c
new file mode 100644
index 0000000000..f16c4da102
--- /dev/null
+++ b/xen/arch/x86/usercopy.c
@@ -0,0 +1,139 @@
+/* 
+ * User address space access functions.
+ *
+ * Copyright 1997 Andi Kleen <ak@muc.de>
+ * Copyright 1997 Linus Torvalds
+ * Copyright 2002 Andi Kleen <ak@suse.de>
+ */
+
+#include <xen/config.h>
+#include <xen/lib.h>
+#include <asm/uaccess.h>
+
+unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned n)
+{
+	unsigned long __d0, __d1, __d2, __n = n;
+	__asm__ __volatile__(
+		"	cmp  $"STR(2*BYTES_PER_LONG-1)",%0\n"
+		"	jbe  1f\n"
+		"	mov  %1,%0\n"
+		"	neg  %0\n"
+		"	and  $"STR(BYTES_PER_LONG-1)",%0\n"
+		"	sub  %0,%3\n"
+		"4:	rep; movsb\n" /* make 'to' address aligned */
+		"	mov  %3,%0\n"
+		"	shr  $"STR(LONG_BYTEORDER)",%0\n"
+		"	and  $"STR(BYTES_PER_LONG-1)",%3\n"
+		"	.align 2,0x90\n"
+		"0:	rep; movs"__OS"\n" /* as many words as possible... */
+		"	mov  %3,%0\n"
+		"1:	rep; movsb\n" /* ...remainder copied as bytes */
+		"2:\n"
+		".section .fixup,\"ax\"\n"
+		"5:	add %3,%0\n"
+		"	jmp 2b\n"
+		"3:	lea 0(%3,%0,"STR(BYTES_PER_LONG)"),%0\n"
+		"	jmp 2b\n"
+		".previous\n"
+		".section __ex_table,\"a\"\n"
+		"	"__FIXUP_ALIGN"\n"
+		"	"__FIXUP_WORD" 4b,5b\n"
+		"	"__FIXUP_WORD" 0b,3b\n"
+		"	"__FIXUP_WORD" 1b,2b\n"
+		".previous"
+		: "=&c"(__n), "=&D" (__d0), "=&S" (__d1), "=r"(__d2)
+		: "3"(__n), "0"(__n), "1"(to), "2"(from)
+		: "memory");
+	return (unsigned)__n;
+}
+
+unsigned long
+__copy_from_user_ll(void *to, const void __user *from, unsigned n)
+{
+	unsigned long __d0, __d1, __d2, __n = n;
+	__asm__ __volatile__(
+		"	cmp  $"STR(2*BYTES_PER_LONG-1)",%0\n"
+		"	jbe  1f\n"
+		"	mov  %1,%0\n"
+		"	neg  %0\n"
+		"	and  $"STR(BYTES_PER_LONG-1)",%0\n"
+		"	sub  %0,%3\n"
+		"4:	rep; movsb\n" /* make 'to' address aligned */
+		"	mov  %3,%0\n"
+		"	shr  $"STR(LONG_BYTEORDER)",%0\n"
+		"	and  $"STR(BYTES_PER_LONG-1)",%3\n"
+		"	.align 2,0x90\n"
+		"0:	rep; movs"__OS"\n" /* as many words as possible... */
+		"	mov  %3,%0\n"
+		"1:	rep; movsb\n" /* ...remainder copied as bytes */
+		"2:\n"
+		".section .fixup,\"ax\"\n"
+		"5:	add %3,%0\n"
+		"	jmp 6f\n"
+		"3:	lea 0(%3,%0,"STR(BYTES_PER_LONG)"),%0\n"
+		"6:	push %0\n"
+		"	push %%"__OP"ax\n"
+		"	xor  %%eax,%%eax\n"
+		"	rep; stosb\n"
+		"	pop  %%"__OP"ax\n"
+		"	pop  %0\n"
+		"	jmp 2b\n"
+		".previous\n"
+		".section __ex_table,\"a\"\n"
+		"	"__FIXUP_ALIGN"\n"
+		"	"__FIXUP_WORD" 4b,5b\n"
+		"	"__FIXUP_WORD" 0b,3b\n"
+		"	"__FIXUP_WORD" 1b,6b\n"
+		".previous"
+		: "=&c"(__n), "=&D" (__d0), "=&S" (__d1), "=r"(__d2)
+		: "3"(__n), "0"(__n), "1"(to), "2"(from)
+		: "memory");
+	return (unsigned)__n;
+}
+
+/**
+ * copy_to_user: - Copy a block of data into user space.
+ * @to:   Destination address, in user space.
+ * @from: Source address, in kernel space.
+ * @n:    Number of bytes to copy.
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * Copy data from kernel space to user space.
+ *
+ * Returns number of bytes that could not be copied.
+ * On success, this will be zero.
+ */
+unsigned long
+copy_to_user(void __user *to, const void *from, unsigned n)
+{
+	if (access_ok(to, n))
+		n = __copy_to_user(to, from, n);
+	return n;
+}
+
+/**
+ * copy_from_user: - Copy a block of data from user space.
+ * @to:   Destination address, in kernel space.
+ * @from: Source address, in user space.
+ * @n:    Number of bytes to copy.
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * Copy data from user space to kernel space.
+ *
+ * Returns number of bytes that could not be copied.
+ * On success, this will be zero.
+ *
+ * If some data could not be copied, this function will pad the copied
+ * data to the requested size using zero bytes.
+ */
+unsigned long
+copy_from_user(void *to, const void __user *from, unsigned n)
+{
+	if (access_ok(from, n))
+		n = __copy_from_user(to, from, n);
+	else
+		memset(to, 0, n);
+	return n;
+}