syslet: introduce abi structs

This patch adds the architecture independent structures of the
syslet ABI. 

Signed-off-by: Zach Brown <zach.brown@oracle.com>

---
 include/linux/syslet-abi.h |   34 ++++++++++++++++++++++++++++++++++
 1 files changed, 34 insertions(+), 0 deletions(-)

diff --git a/include/linux/syslet-abi.h b/include/linux/syslet-abi.h
new file mode 100644
index 0000000..a8bc1a3
--- /dev/null
+++ b/include/linux/syslet-abi.h
@@ -0,0 +1,34 @@
+#ifndef _LINUX_SYSLET_ABI_H
+#define _LINUX_SYSLET_ABI_H
+
+#include <asm/syslet-abi.h> /* for struct syslet_frame */
+
+struct syslet_args {
+	u64 completion_ring_ptr;
+	u64 caller_data;
+	struct syslet_frame frame;
+};
+
+struct syslet_completion {
+	u64 status;
+	u64 caller_data;
+};
+
+/*
+ * The ring follows the "wrapping" convention as described by Andrew at:
+ * 	http://lkml.org/lkml/2007/4/11/276
+ * The head is updated by the kernel as completions are added and the
+ * tail is updated by userspace as completions are removed.
+ *
+ * The number of elements must be a power of two and the ring must be
+ * aligned to a u64.
+ */
+struct syslet_ring {
+	u32 kernel_head;
+	u32 user_tail;
+	u32 elements;
+	u32 wait_group;
+	struct syslet_completion comp[0];
+};
+
+#endif