Use struct for time_value_t and define seconds as long_integer_t.

On 64 bit kernels, seconds will be 64 bits long and won't suffer from
the 2038 problem. We also add a new type rpc_time_value_t to handle the
conversion between 32 bit userland and 64 bit kernel.
Message-Id: <Y50kIaIgaIdGjDAk@mars>

2 files changed, 38 insertions, 2 deletions

diff --git a/include/mach/mach_types.defs b/include/mach/mach_types.defs
index 74b85232..da74a3f2 100644
--- a/include/mach/mach_types.defs
+++ b/include/mach/mach_types.defs
@@ -261,7 +261,18 @@ type kernel_version_t		= (MACH_MSG_TYPE_STRING, 512*8);
 
 type kernel_boot_info_t		= (MACH_MSG_TYPE_STRING, 4096*8);
 
-type time_value_t		= struct[2] of integer_t;
+type rpc_time_value_t		= struct {
+  rpc_long_integer_t seconds;
+  integer_t microseconds;
+};
+type time_value_t = rpc_time_value_t
+#if defined(KERNEL_SERVER)
+    intran: time_value_t convert_time_value_from_user(rpc_time_value_t)
+    outtran: rpc_time_value_t convert_time_value_to_user(time_value_t)
+#elif defined(KERNEL_USER)
+    ctype: rpc_time_value_t
+#endif
+    ;
 
 type emulation_vector_t		= ^array[] of vm_offset_t;
 
diff --git a/include/mach/time_value.h b/include/mach/time_value.h
index 3a9c384c..53692bcf 100644
--- a/include/mach/time_value.h
+++ b/include/mach/time_value.h
@@ -33,12 +33,37 @@
  *	Time value returned by kernel.
  */
 
+struct rpc_time_value {
+	/* TODO: this should be 64 bits regardless of the arch to be Y2038 proof. */
+	rpc_long_integer_t seconds;
+	integer_t microseconds;
+};
+typedef struct rpc_time_value rpc_time_value_t;
+
+/*
+ *	Time value used by kernel.
+ */
 struct time_value {
-	integer_t	seconds;
+	long_integer_t	seconds;
 	integer_t	microseconds;
 };
 typedef	struct time_value	time_value_t;
 
+/**
+ * Functions used by Mig to perform user to kernel conversion and vice-versa.
+ * We only do this because we may run a 64 bit kernel with a 32 bit user space.
+ */
+static inline rpc_time_value_t convert_time_value_to_user(time_value_t tv)
+{
+	rpc_time_value_t user = {.seconds = tv.seconds, .microseconds = tv.microseconds};
+	return user;
+}
+static inline time_value_t convert_time_value_from_user(rpc_time_value_t tv)
+{
+	time_value_t kernel = {.seconds = tv.seconds, .microseconds = tv.microseconds};
+	return kernel;
+}
+
 /*
  *	Macros to manipulate time values.  Assume that time values
  *	are normalized (microseconds <= 999999).