Give a functional include/asm-sh/futex.h

[Kaz K. <kk...@rr...>]

The last problem is that the newer libc needs more complete futex
support in the kernel.  Now SH uses include/asm-generic/futex.h
which doesn't give the required functions.  The attached patch is
an obvious "last resort" implementation for the uni processor.
If the CPU has ll/sc insns, they can be used like as the other
architectures do.  I'll leave the llsc version to the folks who
can access such CPU.

Regards,
	kaz

Signed-off-by: Kaz Kojima <kk...@rr...>

--- GIT/linux-2.6/include/asm-sh/futex.h	2006-08-29 08:00:06.000000000 +0900
+++ linux-2.6.22-rc4/include/asm-sh/futex.h	2007-06-14 17:36:40.000000000 +0900
@@ -1,6 +1,101 @@
 #ifndef _ASM_FUTEX_H
 #define _ASM_FUTEX_H
 
-#include <asm-generic/futex.h>
+#ifdef __KERNEL__
 
+#include <linux/futex.h>
+#include <asm/errno.h>
+#include <asm/uaccess.h>
+
+static inline int futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
+{
+	int op = (encoded_op >> 28) & 7;
+	int cmp = (encoded_op >> 24) & 15;
+	int oparg = (encoded_op << 8) >> 20;
+	int cmparg = (encoded_op << 20) >> 20;
+	int oldval = 0, ret;
+	unsigned long flags;
+
+	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+		oparg = 1 << oparg;
+
+	if (!access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
+		return -EFAULT;
+
+	pagefault_disable();
+
+	local_irq_save(flags);
+
+	switch (op) {
+	case FUTEX_OP_SET:
+		ret = get_user(oldval, uaddr);
+		if (!ret)
+			ret = put_user(oparg, uaddr);
+		break;
+	case FUTEX_OP_ADD:
+		ret = get_user(oldval, uaddr);
+		if (!ret)
+			ret = put_user(oldval + oparg, uaddr);
+		break;
+	case FUTEX_OP_OR:
+		ret = get_user(oldval, uaddr);
+		if (!ret)
+			ret = put_user(oldval | oparg, uaddr);
+		break;
+	case FUTEX_OP_ANDN:
+		ret = get_user(oldval, uaddr);
+		if (!ret)
+			ret = put_user(oldval & oparg, uaddr);
+		break;
+	case FUTEX_OP_XOR:
+		ret = get_user(oldval, uaddr);
+		if (!ret)
+			ret = put_user(oldval ^ oparg, uaddr);
+		break;
+	default:
+		ret = -ENOSYS;
+	}
+
+	local_irq_restore(flags);
+
+	pagefault_enable();
+
+	if (!ret) {
+		switch (cmp) {
+		case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
+		case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
+		case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
+		case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
+		case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
+		case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
+		default: ret = -ENOSYS;
+		}
+	}
+	return ret;
+}
+
+static inline int
+futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
+{
+	int ret, prev;
+	unsigned long flags;
+
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+		return -EFAULT;
+
+	local_irq_save(flags);
+
+	ret = get_user(prev, uaddr);
+	if (!ret && oldval == prev)
+		ret = put_user(newval, uaddr);
+
+	local_irq_restore(flags);
+
+	if (ret)
+		return ret;
+
+        return prev;
+}
+
+#endif /* __KERNEL__ */
 #endif