diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index 91d26ce..65e0117 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -63,6 +63,7 @@
     # The kernel usage of __unused for unused struct fields conflicts with the macro defined in <sys/cdefs.h>.
     "__unused": "__linux_unused",
     # The kernel usage of C++ keywords causes problems for C++ code so rename.
+    "class": "__linux_class",
     "private": "__linux_private",
     "virtual": "__linux_virtual",
     # The non-64 stuff is legacy; msqid64_ds/ipc64_perm is what userspace wants.
@@ -125,6 +126,8 @@
           # These are required to support the above functions.
           "__fswahw32",
           "__fswahb32",
+          # This is used by various macros in <linux/ioprio.h>.
+          "ioprio_value",
         ]
     )
 
diff --git a/libc/kernel/uapi/linux/ioprio.h b/libc/kernel/uapi/linux/ioprio.h
index c6dc42a..1fbedd0 100644
--- a/libc/kernel/uapi/linux/ioprio.h
+++ b/libc/kernel/uapi/linux/ioprio.h
@@ -61,6 +61,10 @@
   IOPRIO_HINT_DEV_DURATION_LIMIT_7 = 7,
 };
 #define IOPRIO_BAD_VALUE(val,max) ((val) < 0 || (val) >= (max))
-#define IOPRIO_PRIO_VALUE(class,level) ioprio_value(class, level, IOPRIO_HINT_NONE)
-#define IOPRIO_PRIO_VALUE_HINT(class,level,hint) ioprio_value(class, level, hint)
+static __always_inline __u16 ioprio_value(int __linux_class, int level, int hint) {
+  if(IOPRIO_BAD_VALUE(__linux_class, IOPRIO_NR_CLASSES) || IOPRIO_BAD_VALUE(level, IOPRIO_NR_LEVELS) || IOPRIO_BAD_VALUE(hint, IOPRIO_NR_HINTS)) return IOPRIO_CLASS_INVALID << IOPRIO_CLASS_SHIFT;
+  return(__linux_class << IOPRIO_CLASS_SHIFT) | (hint << IOPRIO_HINT_SHIFT) | level;
+}
+#define IOPRIO_PRIO_VALUE(class,level) ioprio_value(__linux_class, level, IOPRIO_HINT_NONE)
+#define IOPRIO_PRIO_VALUE_HINT(class,level,hint) ioprio_value(__linux_class, level, hint)
 #endif