FUCK

CODE/UTSM/include/utsm/hypercall.h

@@ -0,0 +1,39 @@
+#ifndef UTSM_HYPERCALL_H
+#define UTSM_HYPERCALL_H
+
+/* UTSM-side VMCALL hypercall handler.
+ *
+ * When the Linux guest executes a VMCALL instruction, it triggers a VM-Exit
+ * with exit reason EXIT_VMCALL (18). The guest places:
+ *   RAX = UTSM_HCALL_MAGIC | op    (identifies this as a UTSM hypercall)
+ *   RDI = arg0
+ *   RSI = arg1
+ *   RDX = arg2
+ *
+ * The handler validates the magic, dispatches to the operation handler,
+ * writes the return value into GUEST_RAX, and advances GUEST_RIP past
+ * the VMCALL instruction so the guest resumes normally.
+ *
+ * If the magic doesn't match, the handler returns a VMFAIL indication
+ * (by setting the VMCS vm-exit instruction error), which causes the guest
+ * to see VMCALL fail. Phase 1.3: we just return -UTSM_HCALL_NOSYS.
+ *
+ * Protocol details in CODE/utsm-ipc/ipc_proto.h.
+ */
+
+#include <utsm/types.h>
+
+/* VM-Exit handler for VMCALL (exit reason 18).
+ *
+ * Reads guest RAX/RDI/RSI/RDX from the VMCS save area (passed in by the
+ * assembly exit stub), dispatches the hypercall, writes the result to
+ * GUEST_RAX, and advances GUEST_RIP.
+ *
+ * Returns 1 to resume the guest, 0 to terminate. */
+int hypercall_handle(u64 guest_rax, u64 guest_rdi, u64 guest_rsi, u64 guest_rdx,
+                     u64 guest_rip, u64 instr_len);
+
+/* Statistics */
+u64 hypercall_get_count(void);
+
+#endif /* UTSM_HYPERCALL_H */