add vmm_get and vmm_set

Author: nyuichi

include/hv.h

@@ -75,6 +75,16 @@ typedef enum {
   VMM_X64_REGISTERS_MAX,
 } vmm_x64_reg_t;
 
+enum {
+  VMM_CTRL_EXIT_REASON,
+};
+
+enum {
+  VMM_EXIT_HLT,
+  VMM_EXIT_IO,
+  VMM_EXIT_REASONS_MAX,
+};
+
 int vmm_create(void);
 int vmm_destroy(void);
 
@@ -90,6 +100,9 @@ int vmm_cpu_write_register(vmm_x64_reg_t reg, uint64_t value);
 int vmm_cpu_read_msr(uint32_t msr, uint64_t *value);
 int vmm_cpu_write_msr(uint32_t msr, uint64_t value);
 
+int vmm_get(int id, uint64_t *value);
+int vmm_set(int id, uint64_t value);
+
 #ifdef __cplusplus
 }
 #endif

src/hv_kvm.c

@@ -188,3 +188,18 @@ vmm_cpu_write_register(vmm_x64_reg_t reg, uint64_t value)
 
   return 0;
 }
+
+int
+vmm_get(int id, uint64_t *value)
+{
+  assert(id == VMM_CTRL_EXIT_REASON);
+
+  switch (run->exit_reason) {
+  case KVM_EXIT_HLT: *value = VMM_EXIT_HLT; break;
+  case KVM_EXIT_IO:  *value = VMM_EXIT_IO; break;
+  default:
+    *value = VMM_EXIT_REASONS_MAX;
+    return -1;
+  }
+  return 0;
+}

test/main.c

@@ -67,23 +67,26 @@ int main(void)
   /* Repeatedly run code and handle VM exits. */
   while (1) {
     vmm_cpu_run();
-    switch (run->exit_reason) {
-    case KVM_EXIT_HLT:
+    uint64_t exit_reason;
+    vmm_get(VMM_CTRL_EXIT_REASON, &exit_reason);
+    switch (exit_reason) {
+    case VMM_EXIT_HLT:
       puts("KVM_EXIT_HLT");
       return 0;
-    case KVM_EXIT_IO:
-      if (run->io.direction == KVM_EXIT_IO_OUT && run->io.size == 1 && run->io.port == 0x3f8 && run->io.count == 1)
-        putchar(*(((char *)run) + run->io.data_offset));
-      else
-        errx(1, "unhandled KVM_EXIT_IO");
-      break;
-    case KVM_EXIT_FAIL_ENTRY:
-      errx(1, "KVM_EXIT_FAIL_ENTRY: hardware_entry_failure_reason = 0x%llx",
-           (unsigned long long)run->fail_entry.hardware_entry_failure_reason);
-    case KVM_EXIT_INTERNAL_ERROR:
-      errx(1, "KVM_EXIT_INTERNAL_ERROR: suberror = 0x%x", run->internal.suberror);
+    /* case KVM_EXIT_IO: */
+    /*   if (run->io.direction == KVM_EXIT_IO_OUT && run->io.size == 1 && run->io.port == 0x3f8 && run->io.count == 1) */
+    /*     putchar(*(((char *)run) + run->io.data_offset)); */
+    /*   else */
+    /*     errx(1, "unhandled KVM_EXIT_IO"); */
+    /*   break; */
+    /* case KVM_EXIT_FAIL_ENTRY: */
+    /*   errx(1, "KVM_EXIT_FAIL_ENTRY: hardware_entry_failure_reason = 0x%llx", */
+    /*        (unsigned long long)run->fail_entry.hardware_entry_failure_reason); */
+    /* case KVM_EXIT_INTERNAL_ERROR: */
+    /*   errx(1, "KVM_EXIT_INTERNAL_ERROR: suberror = 0x%x", run->internal.suberror); */
     default:
-      errx(1, "exit_reason = 0x%x", run->exit_reason);
+     fprintf(stderr, "exit_reason = 0x%x", exit_reason);
+     abort();
     }
   }
 }