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-rw-r--r--arch/parisc/include/asm/futex.h77
1 files changed, 77 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/futex.h b/arch/parisc/include/asm/futex.h
new file mode 100644
index 000000000000..0c705c3a55ef
--- /dev/null
+++ b/arch/parisc/include/asm/futex.h
@@ -0,0 +1,77 @@
+#ifndef _ASM_PARISC_FUTEX_H
+#define _ASM_PARISC_FUTEX_H
+
+#ifdef __KERNEL__
+
+#include <linux/futex.h>
+#include <linux/uaccess.h>
+#include <asm/errno.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;
+	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
+		oparg = 1 << oparg;
+
+	if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
+		return -EFAULT;
+
+	pagefault_disable();
+
+	switch (op) {
+	case FUTEX_OP_SET:
+	case FUTEX_OP_ADD:
+	case FUTEX_OP_OR:
+	case FUTEX_OP_ANDN:
+	case FUTEX_OP_XOR:
+	default:
+		ret = -ENOSYS;
+	}
+
+	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;
+}
+
+/* Non-atomic version */
+static inline int
+futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
+{
+	int err = 0;
+	int uval;
+
+	/* futex.c wants to do a cmpxchg_inatomic on kernel NULL, which is
+	 * our gateway page, and causes no end of trouble...
+	 */
+	if (segment_eq(KERNEL_DS, get_fs()) && !uaddr)
+		return -EFAULT;
+
+	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(int)))
+		return -EFAULT;
+
+	err = get_user(uval, uaddr);
+	if (err) return -EFAULT;
+	if (uval == oldval)
+		err = put_user(newval, uaddr);
+	if (err) return -EFAULT;
+	return uval;
+}
+
+#endif /*__KERNEL__*/
+#endif /*_ASM_PARISC_FUTEX_H*/