Index: pkg/mod/github.com/nsip/gommap@v0.0.0-20181229045655-f7881c3a959f/mmap_freebsd_386.go
--- pkg/mod/github.com/nsip/gommap@v0.0.0-20181229045655-f7881c3a959f/mmap_freebsd_386.go.orig	2020-01-02 09:33:38.168423000 +0100
+++ pkg/mod/github.com/nsip/gommap@v0.0.0-20181229045655-f7881c3a959f/mmap_freebsd_386.go	2020-01-02 09:33:38.168213000 +0100
@@ -0,0 +1,12 @@
+package gommap
+
+import "syscall"
+
+func mmap_syscall(addr, length, prot, flags, fd uintptr, offset int64) (uintptr, error) {
+	page := uintptr(offset / 4096)
+	if offset != int64(page)*4096 {
+		return 0, syscall.EINVAL
+	}
+	addr, _, err := syscall.Syscall6(syscall.SYS_MMAP2, addr, length, prot, flags, fd, page)
+	return addr, err
+}
Index: pkg/mod/github.com/nsip/gommap@v0.0.0-20181229045655-f7881c3a959f/mmap_freebsd_amd64.go
--- pkg/mod/github.com/nsip/gommap@v0.0.0-20181229045655-f7881c3a959f/mmap_freebsd_amd64.go.orig	2020-01-02 09:33:38.169053000 +0100
+++ pkg/mod/github.com/nsip/gommap@v0.0.0-20181229045655-f7881c3a959f/mmap_freebsd_amd64.go	2020-01-02 09:33:38.168922000 +0100
@@ -0,0 +1,8 @@
+package gommap
+
+import "syscall"
+
+func mmap_syscall(addr, length, prot, flags, fd uintptr, offset int64) (uintptr, error) {
+	addr, _, err := syscall.Syscall6(syscall.SYS_MMAP, addr, length, prot, flags, fd, uintptr(offset))
+	return addr, err
+}
