tests: fix data race in TestDeletedInodePath

Running `go test ./... -race` showed a data race
at `rootNode.deleted`. This race cannot really happen,
but the race detector does not know that as the calls
go through FUSE an appear to not be synchronized.

Use atomic loads and stores to make the race detector
happy.

Change-Id: I26bd3e7d8efdd5b967fdb360eb17d7f71a8005c8

fs/bridge_test.go

@@ -9,6 +9,7 @@ import (
 	"log"
 	"os"
 	"strings"
+	"sync/atomic"
 	"syscall"
 	"testing"
 	"unsafe"
@@ -155,7 +156,7 @@ func TestDeletedInodePath(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	rootNode.deleted = true
+	atomic.StoreInt32(&rootNode.deleted, 1)
 
 	// Our Getattr implementation `testDeletedIno.Getattr` should return
 	// ENFILE when everything looks ok, EILSEQ otherwise.
@@ -169,11 +170,12 @@ func TestDeletedInodePath(t *testing.T) {
 type testDeletedIno struct {
 	Inode
 
-	deleted bool
+	deleted int32
 }
 
 func (n *testDeletedIno) Lookup(ctx context.Context, name string, out *fuse.EntryOut) (*Inode, syscall.Errno) {
-	if n.Root().Operations().(*testDeletedIno).deleted {
+	ino := n.Root().Operations().(*testDeletedIno)
+	if atomic.LoadInt32(&ino.deleted) == 1 {
 		return nil, syscall.ENOENT
 	}
 	if name != "dir" {