This patch adds --tmpfs as a option for mounting tmpfs on directories

It will Tar up contents of child directory onto tmpfs if mounted over

This patch will use the new PreMount and PostMount hooks to "tar"
up the contents of the base image on top of tmpfs mount points.

Signed-off-by: Dan Walsh <dwalsh@redhat.com>
Upstream-commit: b3e527dfd242ad30c0297c8b257862116cf2c50e
Component: engine

components/engine/integration-cli/docker_api_containers_test.go

@@ -212,7 +212,7 @@ func (s *DockerSuite) TestContainerApiStartDupVolumeBinds(c *check.C) {
 	status, body, err := sockRequest("POST", "/containers/"+name+"/start", config)
 	c.Assert(err, checker.IsNil)
 	c.Assert(status, checker.Equals, http.StatusInternalServerError)
-	c.Assert(string(body), checker.Contains, "Duplicate bind", check.Commentf("Expected failure due to duplicate bind mounts to same path, instead got: %q with error: %v", string(body), err))
+	c.Assert(string(body), checker.Contains, "Duplicate mount point", check.Commentf("Expected failure due to duplicate bind mounts to same path, instead got: %q with error: %v", string(body), err))
 }
 
 func (s *DockerSuite) TestContainerApiStartVolumesFrom(c *check.C) {

components/engine/integration-cli/docker_cli_run_test.go

@@ -375,10 +375,10 @@ func (s *DockerSuite) TestRunNoDupVolumes(c *check.C) {
 	mountstr2 := path2 + someplace
 
 	if out, _, err := dockerCmdWithError("run", "-v", mountstr1, "-v", mountstr2, "busybox", "true"); err == nil {
-		c.Fatal("Expected error about duplicate volume definitions")
+		c.Fatal("Expected error about duplicate mount definitions")
 	} else {
-		if !strings.Contains(out, "Duplicate bind mount") {
-			c.Fatalf("Expected 'duplicate volume' error, got %v", out)
+		if !strings.Contains(out, "Duplicate mount point") {
+			c.Fatalf("Expected 'duplicate mount point' error, got %v", out)
 		}
 	}
 }

components/engine/integration-cli/docker_cli_run_unix_test.go

@@ -438,3 +438,21 @@ func (s *DockerSuite) TestRunWithShmSize(c *check.C) {
 	c.Assert(err, check.IsNil)
 	c.Assert(shmSize, check.Equals, "1073741824")
 }
+
+func (s *DockerSuite) TestRunTmpfsMounts(c *check.C) {
+	// TODO Windows (Post TP4): This test cannot run on a Windows daemon as
+	// Windows does not support tmpfs mounts.
+	testRequires(c, DaemonIsLinux)
+	if out, _, err := dockerCmdWithError("run", "--tmpfs", "/run", "busybox", "touch", "/run/somefile"); err != nil {
+		c.Fatalf("/run directory not mounted on tmpfs %q %s", err, out)
+	}
+	if out, _, err := dockerCmdWithError("run", "--tmpfs", "/run:noexec,nosuid,rw,size=5k,mode=700", "busybox", "touch", "/run/somefile"); err != nil {
+		c.Fatalf("/run failed to mount on tmpfs with valid options %q %s", err, out)
+	}
+	if _, _, err := dockerCmdWithError("run", "--tmpfs", "/run:foobar", "busybox", "touch", "/run/somefile"); err == nil {
+		c.Fatalf("/run mounted on tmpfs when it should have vailed within invalid mount option")
+	}
+	if _, _, err := dockerCmdWithError("run", "--tmpfs", "/run", "-v", "/run:/run", "busybox", "touch", "/run/somefile"); err == nil {
+		c.Fatalf("Should have generated an error saying Duplicate mount  points")
+	}
+}