X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-x86_64%2Ffutex.h;fp=include%2Fasm-x86_64%2Ffutex.h;h=5cdfb08013c38889dc8a42a2dff4c4a3c1833ff8;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=8602c09bf89e8b7e6edc4cb956f832550378d460;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/include/asm-x86_64/futex.h b/include/asm-x86_64/futex.h
index 8602c09bf..5cdfb0801 100644
--- a/include/asm-x86_64/futex.h
+++ b/include/asm-x86_64/futex.h
@@ -55,7 +55,7 @@ futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
 	if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
 		return -EFAULT;
 
-	inc_preempt_count();
+	pagefault_disable();
 
 	switch (op) {
 	case FUTEX_OP_SET:
@@ -78,7 +78,7 @@ futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
 		ret = -ENOSYS;
 	}
 
-	dec_preempt_count();
+	pagefault_enable();
 
 	if (!ret) {
 		switch (cmp) {
@@ -94,5 +94,32 @@ futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
 	return ret;
 }
 
+static inline int
+futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
+{
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+		return -EFAULT;
+
+	__asm__ __volatile__(
+		"1:	" LOCK_PREFIX "cmpxchgl %3, %1		\n"
+
+		"2:	.section .fixup, \"ax\"			\n"
+		"3:	mov     %2, %0				\n"
+		"	jmp     2b				\n"
+		"	.previous				\n"
+
+		"	.section __ex_table, \"a\"		\n"
+		"	.align  8				\n"
+		"	.quad   1b,3b				\n"
+		"	.previous				\n"
+
+		: "=a" (oldval), "=m" (*uaddr)
+		: "i" (-EFAULT), "r" (newval), "0" (oldval)
+		: "memory"
+	);
+
+	return oldval;
+}
+
 #endif
 #endif