diff --git a/libc/kernel/uapi/linux/shm.h b/libc/kernel/uapi/linux/shm.h
index ab319f2..a3071e7 100644
--- a/libc/kernel/uapi/linux/shm.h
+++ b/libc/kernel/uapi/linux/shm.h
@@ -20,6 +20,7 @@
 #define _UAPI_LINUX_SHM_H_
 #include <linux/ipc.h>
 #include <linux/errno.h>
+#include <asm-generic/hugetlb_encode.h>
 #include <unistd.h>
 #define SHMMIN 1
 #define SHMMNI 4096
@@ -42,6 +43,20 @@
 #include <asm/shmbuf.h>
 #define SHM_R 0400
 #define SHM_W 0200
+#define SHM_HUGETLB 04000
+#define SHM_NORESERVE 010000
+#define SHM_HUGE_SHIFT HUGETLB_FLAG_ENCODE_SHIFT
+#define SHM_HUGE_MASK HUGETLB_FLAG_ENCODE_MASK
+#define SHM_HUGE_64KB HUGETLB_FLAG_ENCODE_64KB
+#define SHM_HUGE_512KB HUGETLB_FLAG_ENCODE_512KB
+#define SHM_HUGE_1MB HUGETLB_FLAG_ENCODE_1MB
+#define SHM_HUGE_2MB HUGETLB_FLAG_ENCODE_2MB
+#define SHM_HUGE_8MB HUGETLB_FLAG_ENCODE_8MB
+#define SHM_HUGE_16MB HUGETLB_FLAG_ENCODE_16MB
+#define SHM_HUGE_256MB HUGETLB_FLAG_ENCODE_256MB
+#define SHM_HUGE_1GB HUGETLB_FLAG_ENCODE_1GB
+#define SHM_HUGE_2GB HUGETLB_FLAG_ENCODE_2GB
+#define SHM_HUGE_16GB HUGETLB_FLAG_ENCODE_16GB
 #define SHM_RDONLY 010000
 #define SHM_RND 020000
 #define SHM_REMAP 040000