1 files changed, 142 insertions, 0 deletions
diff --git a/arch/tile/include/asm/futex.h b/arch/tile/include/asm/futex.h
new file mode 100644
index 00000000..d03ec124
--- /dev/null
+++ b/arch/tile/include/asm/futex.h
@@ -0,0 +1,142 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ *
+ * These routines make two important assumptions:
+ *
+ * 1. atomic_t is really an int and can be freely cast back and forth
+ *    (validated in __init_atomic_per_cpu).
+ *
+ * 2. userspace uses sys_cmpxchg() for all atomic operations, thus using
+ *    the same locking convention that all the kernel atomic routines use.
+ */
+
+#ifndef _ASM_TILE_FUTEX_H
+#define _ASM_TILE_FUTEX_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/futex.h>
+#include <linux/uaccess.h>
+#include <linux/errno.h>
+
+extern struct __get_user futex_set(u32 __user *v, int i);
+extern struct __get_user futex_add(u32 __user *v, int n);
+extern struct __get_user futex_or(u32 __user *v, int n);
+extern struct __get_user futex_andn(u32 __user *v, int n);
+extern struct __get_user futex_cmpxchg(u32 __user *v, int o, int n);
+
+#ifndef __tilegx__
+extern struct __get_user futex_xor(u32 __user *v, int n);
+#else
+static inline struct __get_user futex_xor(u32 __user *uaddr, int n)
+{
+	struct __get_user asm_ret = __get_user_4(uaddr);
+	if (!asm_ret.err) {
+		int oldval, newval;
+		do {
+			oldval = asm_ret.val;
+			newval = oldval ^ n;
+			asm_ret = futex_cmpxchg(uaddr, oldval, newval);
+		} while (asm_ret.err == 0 && oldval != asm_ret.val);
+	}
+	return asm_ret;
+}
+#endif
+
+static inline int futex_atomic_op_inuser(int encoded_op, u32 __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 ret;
+	struct __get_user asm_ret;
+
+	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+		oparg = 1 << oparg;
+
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+		return -EFAULT;
+
+	pagefault_disable();
+	switch (op) {
+	case FUTEX_OP_SET:
+		asm_ret = futex_set(uaddr, oparg);
+		break;
+	case FUTEX_OP_ADD:
+		asm_ret = futex_add(uaddr, oparg);
+		break;
+	case FUTEX_OP_OR:
+		asm_ret = futex_or(uaddr, oparg);
+		break;
+	case FUTEX_OP_ANDN:
+		asm_ret = futex_andn(uaddr, oparg);
+		break;
+	case FUTEX_OP_XOR:
+		asm_ret = futex_xor(uaddr, oparg);
+		break;
+	default:
+		asm_ret.err = -ENOSYS;
+	}
+	pagefault_enable();
+
+	ret = asm_ret.err;
+
+	if (!ret) {
+		switch (cmp) {
+		case FUTEX_OP_CMP_EQ:
+			ret = (asm_ret.val == cmparg);
+			break;
+		case FUTEX_OP_CMP_NE:
+			ret = (asm_ret.val != cmparg);
+			break;
+		case FUTEX_OP_CMP_LT:
+			ret = (asm_ret.val < cmparg);
+			break;
+		case FUTEX_OP_CMP_GE:
+			ret = (asm_ret.val >= cmparg);
+			break;
+		case FUTEX_OP_CMP_LE:
+			ret = (asm_ret.val <= cmparg);
+			break;
+		case FUTEX_OP_CMP_GT:
+			ret = (asm_ret.val > cmparg);
+			break;
+		default:
+			ret = -ENOSYS;
+		}
+	}
+	return ret;
+}
+
+static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
+						u32 oldval, u32 newval)
+{
+	struct __get_user asm_ret;
+
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
+		return -EFAULT;
+
+	asm_ret = futex_cmpxchg(uaddr, oldval, newval);
+	*uval = asm_ret.val;
+	return asm_ret.err;
+}
+
+#ifndef __tilegx__
+/* Return failure from the atomic wrappers. */
+struct __get_user __atomic_bad_address(int __user *addr);
+#endif
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _ASM_TILE_FUTEX_H */