diff options
Diffstat (limited to 'pkg/memutil')
-rw-r--r-- | pkg/memutil/BUILD | 11 | ||||
-rw-r--r-- | pkg/memutil/memutil_unsafe.go | 42 |
2 files changed, 53 insertions, 0 deletions
diff --git a/pkg/memutil/BUILD b/pkg/memutil/BUILD new file mode 100644 index 000000000..71b48a972 --- /dev/null +++ b/pkg/memutil/BUILD @@ -0,0 +1,11 @@ +load("//tools/go_stateify:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "memutil", + srcs = ["memutil_unsafe.go"], + importpath = "gvisor.googlesource.com/gvisor/pkg/memutil", + visibility = ["//visibility:public"], + deps = ["@org_golang_x_sys//unix:go_default_library"], +) diff --git a/pkg/memutil/memutil_unsafe.go b/pkg/memutil/memutil_unsafe.go new file mode 100644 index 000000000..979d942a9 --- /dev/null +++ b/pkg/memutil/memutil_unsafe.go @@ -0,0 +1,42 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build linux + +// Package memutil provides a wrapper for the memfd_create() system call. +package memutil + +import ( + "fmt" + "syscall" + "unsafe" + + "golang.org/x/sys/unix" +) + +// CreateMemFD creates a memfd file and returns the fd. +func CreateMemFD(name string, flags int) (int, error) { + p, err := syscall.BytePtrFromString(name) + if err != nil { + return -1, err + } + fd, _, e := syscall.Syscall(unix.SYS_MEMFD_CREATE, uintptr(unsafe.Pointer(p)), uintptr(flags), 0) + if e != 0 { + if e == syscall.ENOSYS { + return -1, fmt.Errorf("memfd_create(2) is not implemented. Check that you have Linux 3.17 or higher") + } + return -1, e + } + return int(fd), nil +} |