1 files changed, 83 insertions, 0 deletions
diff --git a/mini-os/hypervisor.c b/mini-os/hypervisor.c
new file mode 100644
index 0000000000..cf3349426e
--- /dev/null
+++ b/mini-os/hypervisor.c
@@ -0,0 +1,83 @@
+/******************************************************************************
+ * hypervisor.c
+ * 
+ * Communication to/from hypervisor.
+ *
+ * Copied from XenoLinux and adjusted by Rolf.Neugebauer@intel.com
+ * 
+ * Copyright (c) 2002, K A Fraser
+ */
+
+#include <os.h>
+#include <hypervisor.h>
+
+static unsigned long event_mask = 0;
+static unsigned long ev_err_count;
+
+void do_hypervisor_callback(struct pt_regs *regs)
+{
+    unsigned long events, flags;
+    shared_info_t *shared = HYPERVISOR_shared_info;
+
+    do {
+        /* Specialised local_irq_save(). */
+        flags = test_and_clear_bit(EVENTS_MASTER_ENABLE_BIT, 
+                                   &shared->events_mask);
+        barrier();
+
+        events  = xchg(&shared->events, 0);
+        events &= event_mask;
+
+        /* 'events' now contains some pending events to handle. */
+        __asm__ __volatile__ (
+            "   push %1                            ;"
+            "   sub  $4,%%esp                      ;"
+            "   jmp  2f                            ;"
+            "1: btrl %%eax,%0                      ;" /* clear bit     */
+            "   mov  %%eax,(%%esp)                 ;"
+            "   call do_event                      ;" /* do_event(event) */
+            "2: bsfl %0,%%eax                      ;" /* %eax == bit # */
+            "   jnz  1b                            ;"
+            "   add  $8,%%esp                      ;"
+            /* we use %ebx because it is callee-saved */
+            : : "b" (events), "r" (regs)
+            /* clobbered by callback function calls */
+            : "eax", "ecx", "edx", "memory" ); 
+
+        /* Specialised local_irq_restore(). */
+        if ( flags ) set_bit(EVENTS_MASTER_ENABLE_BIT, &shared->events_mask);
+        barrier();
+    }
+    while ( shared->events );
+}
+
+
+
+/*
+ * Define interface to generic handling in irq.c
+ */
+
+void enable_hypervisor_event(unsigned int ev)
+{
+    set_bit(ev, &event_mask);
+    set_bit(ev, &HYPERVISOR_shared_info->events_mask);
+    if ( test_bit(EVENTS_MASTER_ENABLE_BIT, 
+                  &HYPERVISOR_shared_info->events_mask) )
+        do_hypervisor_callback(NULL);
+}
+
+void disable_hypervisor_event(unsigned int ev)
+{
+    clear_bit(ev, &event_mask);
+    clear_bit(ev, &HYPERVISOR_shared_info->events_mask);
+}
+
+void ack_hypervisor_event(unsigned int ev)
+{
+    if ( !(event_mask & (1<<ev)) )
+    {
+        //printk("Unexpected hypervisor event %d\n", ev);
+        atomic_inc((atomic_t *)&ev_err_count);
+    }
+    set_bit(ev, &HYPERVISOR_shared_info->events_mask);
+}