Port eventfd to VFS2.

And move sys_timerfd.go to just timerfd.go for consistency.

Updates #1475.

PiperOrigin-RevId: 309835029

1 files changed, 96 insertions, 0 deletions

diff --git a/pkg/sentry/vfs/eventfd_test.go b/pkg/sentry/vfs/eventfd_test.go
new file mode 100644
index 000000000..2dff2d10b
--- /dev/null
+++ b/pkg/sentry/vfs/eventfd_test.go
@@ -0,0 +1,96 @@
+// 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.
+
+package vfs
+
+import (
+	"testing"
+
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/contexttest"
+	"gvisor.dev/gvisor/pkg/usermem"
+	"gvisor.dev/gvisor/pkg/waiter"
+)
+
+func TestEventFD(t *testing.T) {
+	initVals := []uint64{
+		0,
+		// Using a non-zero initial value verifies that writing to an
+		// eventfd signals when the eventfd's counter was already
+		// non-zero.
+		343,
+	}
+
+	for _, initVal := range initVals {
+		ctx := contexttest.Context(t)
+		vfsObj := &VirtualFilesystem{}
+		if err := vfsObj.Init(); err != nil {
+			t.Fatalf("VFS init: %v", err)
+		}
+
+		// Make a new eventfd that is writable.
+		eventfd, err := vfsObj.NewEventFD(initVal, false, linux.O_RDWR)
+		if err != nil {
+			t.Fatalf("NewEventFD failed: %v", err)
+		}
+		defer eventfd.DecRef()
+
+		// Register a callback for a write event.
+		w, ch := waiter.NewChannelEntry(nil)
+		eventfd.EventRegister(&w, waiter.EventIn)
+		defer eventfd.EventUnregister(&w)
+
+		data := []byte("00000124")
+		// Create and submit a write request.
+		n, err := eventfd.Write(ctx, usermem.BytesIOSequence(data), WriteOptions{})
+		if err != nil {
+			t.Fatal(err)
+		}
+		if n != 8 {
+			t.Errorf("eventfd.write wrote %d bytes, not full int64", n)
+		}
+
+		// Check if the callback fired due to the write event.
+		select {
+		case <-ch:
+		default:
+			t.Errorf("Didn't get notified of EventIn after write")
+		}
+	}
+}
+
+func TestEventFDStat(t *testing.T) {
+	ctx := contexttest.Context(t)
+	vfsObj := &VirtualFilesystem{}
+	if err := vfsObj.Init(); err != nil {
+		t.Fatalf("VFS init: %v", err)
+	}
+
+	// Make a new eventfd that is writable.
+	eventfd, err := vfsObj.NewEventFD(0, false, linux.O_RDWR)
+	if err != nil {
+		t.Fatalf("NewEventFD failed: %v", err)
+	}
+	defer eventfd.DecRef()
+
+	statx, err := eventfd.Stat(ctx, StatOptions{
+		Mask: linux.STATX_BASIC_STATS,
+	})
+	if err != nil {
+		t.Fatalf("eventfd.Stat failed: %v", err)
+	}
+	if statx.Size != 0 {
+		t.Errorf("eventfd size should be 0")
+	}
+}