From ae1bb08871758844fa23fc7255ffeb0392f9dee6 Mon Sep 17 00:00:00 2001 From: Adin Scannell Date: Tue, 21 May 2019 20:11:26 -0700 Subject: Clean up pipe internals and add fcntl support Pipe internals are made more efficient by avoiding garbage collection. A pool is now used that can be shared by all pipes, and buffers are chained via an intrusive list. The documentation for pipe structures and methods is also simplified and clarified. The pipe tests are now parameterized, so that they are run on all different variants (named pipes, small buffers, default buffers). The pipe buffer sizes are exposed by fcntl, which is now supported by this change. A size change test has been added to the suite. These new tests uncovered a bug regarding the semantics of open named pipes with O_NONBLOCK, which is also fixed by this CL. This fix also addresses the lack of the O_LARGEFILE flag for named pipes. PiperOrigin-RevId: 249375888 Change-Id: I48e61e9c868aedb0cadda2dff33f09a560dee773 --- pkg/sentry/kernel/pipe/buffer_test.go | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 pkg/sentry/kernel/pipe/buffer_test.go (limited to 'pkg/sentry/kernel/pipe/buffer_test.go') diff --git a/pkg/sentry/kernel/pipe/buffer_test.go b/pkg/sentry/kernel/pipe/buffer_test.go new file mode 100644 index 000000000..4b7dbc43f --- /dev/null +++ b/pkg/sentry/kernel/pipe/buffer_test.go @@ -0,0 +1,32 @@ +// Copyright 2019 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. + +package pipe + +import ( + "testing" + "unsafe" + + "gvisor.googlesource.com/gvisor/pkg/sentry/usermem" +) + +func TestBufferSize(t *testing.T) { + bufferSize := unsafe.Sizeof(buffer{}) + if bufferSize < usermem.PageSize { + t.Errorf("buffer is less than a page") + } + if bufferSize > (2 * usermem.PageSize) { + t.Errorf("buffer is greater than two pages") + } +} -- cgit v1.2.3