Merge pull request #2959 from mheon/merge_volume_flags

Merge volume flags implementation

1 files changed, 792 insertions, 0 deletions

diff --git a/pkg/spec/storage.go b/pkg/spec/storage.go
new file mode 100644
index 000000000..55148b606
--- /dev/null
+++ b/pkg/spec/storage.go
@@ -0,0 +1,792 @@
+package createconfig
+
+import (
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+
+	"github.com/containers/libpod/libpod"
+	"github.com/containers/libpod/pkg/util"
+	"github.com/containers/storage/pkg/stringid"
+	spec "github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+const (
+	// TypeBind is the type for mounting host dir
+	TypeBind = "bind"
+	// TypeVolume is the type for named volumes
+	TypeVolume = "volume"
+	// TypeTmpfs is the type for mounting tmpfs
+	TypeTmpfs = "tmpfs"
+)
+
+var (
+	errDuplicateDest = errors.Errorf("duplicate mount destination")
+	optionArgError   = errors.Errorf("must provide an argument for option")
+	noDestError      = errors.Errorf("must set volume destination")
+)
+
+// Parse all volume-related options in the create config into a set of mounts
+// and named volumes to add to the container.
+// Handles --volumes-from, --volumes, --tmpfs, --init, and --init-path flags.
+// TODO: Named volume options -  should we default to rprivate? It bakes into a
+// bind mount under the hood...
+// TODO: handle options parsing/processing via containers/storage/pkg/mount
+func (config *CreateConfig) parseVolumes(runtime *libpod.Runtime) ([]spec.Mount, []*libpod.ContainerNamedVolume, error) {
+	// Add image volumes.
+	baseMounts, baseVolumes, err := config.getImageVolumes()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Add --volumes-from.
+	// Overrides image volumes unconditionally.
+	vFromMounts, vFromVolumes, err := config.getVolumesFrom(runtime)
+	if err != nil {
+		return nil, nil, err
+	}
+	for dest, mount := range vFromMounts {
+		baseMounts[dest] = mount
+	}
+	for dest, volume := range vFromVolumes {
+		baseVolumes[dest] = volume
+	}
+
+	// Next mounts from the --mounts flag.
+	// Do not override yet.
+	unifiedMounts, unifiedVolumes, err := config.getMounts()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Next --volumes flag.
+	// Do not override yet.
+	volumeMounts, volumeVolumes, err := config.getVolumeMounts()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Next --tmpfs flag.
+	// Do not override yet.
+	tmpfsMounts, err := config.getTmpfsMounts()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Unify mounts from --mount, --volume, --tmpfs.
+	// Also add mounts + volumes directly from createconfig.
+	// Start with --volume.
+	for dest, mount := range volumeMounts {
+		if _, ok := unifiedMounts[dest]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+		}
+		unifiedMounts[dest] = mount
+	}
+	for dest, volume := range volumeVolumes {
+		if _, ok := unifiedVolumes[dest]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+		}
+		unifiedVolumes[dest] = volume
+	}
+	// Now --tmpfs
+	for dest, tmpfs := range tmpfsMounts {
+		if _, ok := unifiedMounts[dest]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+		}
+		unifiedMounts[dest] = tmpfs
+	}
+	// Now spec mounts and volumes
+	for _, mount := range config.Mounts {
+		dest := mount.Destination
+		if _, ok := unifiedMounts[dest]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+		}
+		unifiedMounts[dest] = mount
+	}
+	for _, volume := range config.NamedVolumes {
+		dest := volume.Dest
+		if _, ok := unifiedVolumes[dest]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, dest)
+		}
+		unifiedVolumes[dest] = volume
+	}
+
+	// If requested, add container init binary
+	if config.Init {
+		initPath := config.InitPath
+		if initPath == "" {
+			rtc, err := runtime.GetConfig()
+			if err != nil {
+				return nil, nil, err
+			}
+			initPath = rtc.InitPath
+		}
+		initMount, err := config.addContainerInitBinary(initPath)
+		if err != nil {
+			return nil, nil, err
+		}
+		if _, ok := unifiedMounts[initMount.Destination]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, "conflict with mount added by --init to %q", initMount.Destination)
+		}
+		unifiedMounts[initMount.Destination] = initMount
+	}
+
+	// If requested, add tmpfs filesystems for read-only containers.
+	// Need to keep track of which we created, so we don't modify options
+	// for them later...
+	readonlyTmpfs := map[string]bool{
+		"/tmp":     false,
+		"/var/tmp": false,
+		"/run":     false,
+	}
+	if config.ReadOnlyRootfs && config.ReadOnlyTmpfs {
+		options := []string{"rw", "rprivate", "nosuid", "nodev", "tmpcopyup", "size=65536k"}
+		for dest := range readonlyTmpfs {
+			if _, ok := unifiedMounts[dest]; ok {
+				continue
+			}
+			localOpts := options
+			if dest == "/run" {
+				localOpts = append(localOpts, "noexec")
+			}
+			unifiedMounts[dest] = spec.Mount{
+				Destination: dest,
+				Type:        "tmpfs",
+				Source:      "tmpfs",
+				Options:     localOpts,
+			}
+			readonlyTmpfs[dest] = true
+		}
+	}
+
+	// Supercede volumes-from/image volumes with unified volumes from above.
+	// This is an unconditional replacement.
+	for dest, mount := range unifiedMounts {
+		baseMounts[dest] = mount
+	}
+	for dest, volume := range unifiedVolumes {
+		baseVolumes[dest] = volume
+	}
+
+	// Check for conflicts between named volumes and mounts
+	for dest := range baseMounts {
+		if _, ok := baseVolumes[dest]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, "conflict at mount destination %v", dest)
+		}
+	}
+	for dest := range baseVolumes {
+		if _, ok := baseMounts[dest]; ok {
+			return nil, nil, errors.Wrapf(errDuplicateDest, "conflict at mount destination %v", dest)
+		}
+	}
+
+	// Final step: maps to arrays
+	finalMounts := make([]spec.Mount, 0, len(baseMounts))
+	for _, mount := range baseMounts {
+		// All user-added tmpfs mounts need their options processed.
+		// Exception: mounts added by the ReadOnlyTmpfs option, which
+		// contain several exceptions to normal options rules.
+		if mount.Type == TypeTmpfs && !readonlyTmpfs[mount.Destination] {
+			opts, err := util.ProcessTmpfsOptions(mount.Options)
+			if err != nil {
+				return nil, nil, err
+			}
+			mount.Options = opts
+		}
+		finalMounts = append(finalMounts, mount)
+	}
+	finalVolumes := make([]*libpod.ContainerNamedVolume, 0, len(baseVolumes))
+	for _, volume := range baseVolumes {
+		finalVolumes = append(finalVolumes, volume)
+	}
+
+	logrus.Debugf("Got mounts: %v", finalMounts)
+	logrus.Debugf("Got volumes: %v", finalVolumes)
+
+	return finalMounts, finalVolumes, nil
+}
+
+// Parse volumes from - a set of containers whose volumes we will mount in.
+// Grab the containers, retrieve any user-created spec mounts and all named
+// volumes, and return a list of them.
+// Conflicts are resolved simply - the last container specified wins.
+// Container names may be suffixed by mount options after a colon.
+func (config *CreateConfig) getVolumesFrom(runtime *libpod.Runtime) (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+	// TODO: This can probably be disabled now
+	if os.Geteuid() != 0 {
+		return nil, nil, nil
+	}
+
+	// Both of these are maps of mount destination to mount type.
+	// We ensure that each destination is only mounted to once in this way.
+	finalMounts := make(map[string]spec.Mount)
+	finalNamedVolumes := make(map[string]*libpod.ContainerNamedVolume)
+
+	for _, vol := range config.VolumesFrom {
+		options := []string{}
+		splitVol := strings.SplitN(vol, ":", 2)
+		if len(splitVol) == 2 {
+			if strings.Contains(splitVol[1], "Z") ||
+				strings.Contains(splitVol[1], "private") ||
+				strings.Contains(splitVol[1], "slave") ||
+				strings.Contains(splitVol[1], "shared") {
+				return nil, nil, errors.Errorf("invalid options %q, can only specify 'ro', 'rw', and 'z", splitVol[1])
+			}
+			options = strings.Split(splitVol[1], ",")
+			if err := ValidateVolumeOpts(options); err != nil {
+				return nil, nil, err
+			}
+		}
+		ctr, err := runtime.LookupContainer(splitVol[0])
+		if err != nil {
+			return nil, nil, errors.Wrapf(err, "error looking up container %q for volumes-from", splitVol[0])
+		}
+
+		logrus.Debugf("Adding volumes from container %s", ctr.ID())
+
+		// Look up the container's user volumes. This gets us the
+		// destinations of all mounts the user added to the container.
+		userVolumesArr := ctr.UserVolumes()
+
+		// We're going to need to access them a lot, so convert to a map
+		// to reduce looping.
+		// We'll also use the map to indicate if we missed any volumes along the way.
+		userVolumes := make(map[string]bool)
+		for _, dest := range userVolumesArr {
+			userVolumes[dest] = false
+		}
+
+		// Now we get the container's spec and loop through its volumes
+		// and append them in if we can find them.
+		spec := ctr.Spec()
+		if spec == nil {
+			return nil, nil, errors.Errorf("error retrieving container %s spec for volumes-from", ctr.ID())
+		}
+		for _, mnt := range spec.Mounts {
+			if mnt.Type != TypeBind {
+				continue
+			}
+			if _, exists := userVolumes[mnt.Destination]; exists {
+				userVolumes[mnt.Destination] = true
+
+				if len(options) != 0 {
+					mnt.Options = options
+				}
+
+				if _, ok := finalMounts[mnt.Destination]; ok {
+					logrus.Debugf("Overriding mount to %s with new mount from container %s", mnt.Destination, ctr.ID())
+				}
+				finalMounts[mnt.Destination] = mnt
+			}
+		}
+
+		// We're done with the spec mounts. Add named volumes.
+		// Add these unconditionally - none of them are automatically
+		// part of the container, as some spec mounts are.
+		namedVolumes := ctr.NamedVolumes()
+		for _, namedVol := range namedVolumes {
+			if _, exists := userVolumes[namedVol.Dest]; exists {
+				userVolumes[namedVol.Dest] = true
+			}
+
+			if len(options) != 0 {
+				namedVol.Options = options
+			}
+
+			if _, ok := finalMounts[namedVol.Dest]; ok {
+				logrus.Debugf("Overriding named volume mount to %s with new named volume from container %s", namedVol.Dest, ctr.ID())
+			}
+			finalNamedVolumes[namedVol.Dest] = namedVol
+		}
+
+		// Check if we missed any volumes
+		for volDest, found := range userVolumes {
+			if !found {
+				logrus.Warnf("Unable to match volume %s from container %s for volumes-from", volDest, ctr.ID())
+			}
+		}
+	}
+
+	return finalMounts, finalNamedVolumes, nil
+}
+
+// getMounts takes user-provided input from the --mount flag and creates OCI
+// spec mounts and Libpod named volumes.
+// podman run --mount type=bind,src=/etc/resolv.conf,target=/etc/resolv.conf ...
+// podman run --mount type=tmpfs,target=/dev/shm ...
+// podman run --mount type=volume,source=test-volume, ...
+func (config *CreateConfig) getMounts() (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+	finalMounts := make(map[string]spec.Mount)
+	finalNamedVolumes := make(map[string]*libpod.ContainerNamedVolume)
+
+	errInvalidSyntax := errors.Errorf("incorrect mount format: should be --mount type=<bind|tmpfs|volume>,[src=<host-dir|volume-name>,]target=<ctr-dir>[,options]")
+
+	// TODO(vrothberg): the manual parsing can be replaced with a regular expression
+	//                  to allow a more robust parsing of the mount format and to give
+	//                  precise errors regarding supported format versus suppored options.
+	for _, mount := range config.MountsFlag {
+		arr := strings.SplitN(mount, ",", 2)
+		if len(arr) < 2 {
+			return nil, nil, errors.Wrapf(errInvalidSyntax, "%q", mount)
+		}
+		kv := strings.Split(arr[0], "=")
+		// TODO: type is not explicitly required in Docker.
+		// If not specified, it defaults to "volume".
+		if len(kv) != 2 || kv[0] != "type" {
+			return nil, nil, errors.Wrapf(errInvalidSyntax, "%q", mount)
+		}
+
+		tokens := strings.Split(arr[1], ",")
+		switch kv[1] {
+		case TypeBind:
+			mount, err := getBindMount(tokens)
+			if err != nil {
+				return nil, nil, err
+			}
+			if _, ok := finalMounts[mount.Destination]; ok {
+				return nil, nil, errors.Wrapf(errDuplicateDest, mount.Destination)
+			}
+			finalMounts[mount.Destination] = mount
+		case TypeTmpfs:
+			mount, err := getTmpfsMount(tokens)
+			if err != nil {
+				return nil, nil, err
+			}
+			if _, ok := finalMounts[mount.Destination]; ok {
+				return nil, nil, errors.Wrapf(errDuplicateDest, mount.Destination)
+			}
+			finalMounts[mount.Destination] = mount
+		case "volume":
+			volume, err := getNamedVolume(tokens)
+			if err != nil {
+				return nil, nil, err
+			}
+			if _, ok := finalNamedVolumes[volume.Dest]; ok {
+				return nil, nil, errors.Wrapf(errDuplicateDest, volume.Dest)
+			}
+			finalNamedVolumes[volume.Dest] = volume
+		default:
+			return nil, nil, errors.Errorf("invalid fylesystem type %q", kv[1])
+		}
+	}
+
+	return finalMounts, finalNamedVolumes, nil
+}
+
+// Parse a single bind mount entry from the --mount flag.
+func getBindMount(args []string) (spec.Mount, error) {
+	newMount := spec.Mount{
+		Type: TypeBind,
+	}
+
+	setSource := false
+	setDest := false
+
+	for _, val := range args {
+		kv := strings.Split(val, "=")
+		switch kv[0] {
+		case "ro", "nosuid", "nodev", "noexec":
+			// TODO: detect duplication of these options.
+			// (Is this necessary?)
+			newMount.Options = append(newMount.Options, kv[0])
+		case "shared", "rshared", "private", "rprivate", "slave", "rslave", "Z", "z":
+			newMount.Options = append(newMount.Options, kv[0])
+		case "bind-propagation":
+			if len(kv) == 1 {
+				return newMount, errors.Wrapf(optionArgError, kv[0])
+			}
+			newMount.Options = append(newMount.Options, kv[1])
+		case "src", "source":
+			if len(kv) == 1 {
+				return newMount, errors.Wrapf(optionArgError, kv[0])
+			}
+			if err := ValidateVolumeHostDir(kv[1]); err != nil {
+				return newMount, err
+			}
+			newMount.Source = kv[1]
+			setSource = true
+		case "target", "dst", "destination":
+			if len(kv) == 1 {
+				return newMount, errors.Wrapf(optionArgError, kv[0])
+			}
+			if err := ValidateVolumeCtrDir(kv[1]); err != nil {
+				return newMount, err
+			}
+			newMount.Destination = kv[1]
+			setDest = true
+		default:
+			return newMount, errors.Wrapf(util.ErrBadMntOption, kv[0])
+		}
+	}
+
+	if !setDest {
+		return newMount, noDestError
+	}
+
+	if !setSource {
+		newMount.Source = newMount.Destination
+	}
+
+	if err := ValidateVolumeOpts(newMount.Options); err != nil {
+		return newMount, err
+	}
+
+	return newMount, nil
+}
+
+// Parse a single tmpfs mount entry from the --mount flag
+func getTmpfsMount(args []string) (spec.Mount, error) {
+	newMount := spec.Mount{
+		Type:   TypeTmpfs,
+		Source: TypeTmpfs,
+	}
+
+	setDest := false
+
+	for _, val := range args {
+		kv := strings.Split(val, "=")
+		switch kv[0] {
+		case "ro", "nosuid", "nodev", "noexec":
+			newMount.Options = append(newMount.Options, kv[0])
+		case "tmpfs-mode":
+			if len(kv) == 1 {
+				return newMount, errors.Wrapf(optionArgError, kv[0])
+			}
+			newMount.Options = append(newMount.Options, fmt.Sprintf("mode=%s", kv[1]))
+		case "tmpfs-size":
+			if len(kv) == 1 {
+				return newMount, errors.Wrapf(optionArgError, kv[0])
+			}
+			newMount.Options = append(newMount.Options, fmt.Sprintf("size=%s", kv[1]))
+		case "src", "source":
+			return newMount, errors.Errorf("source is not supported with tmpfs mounts")
+		case "target", "dst", "destination":
+			if len(kv) == 1 {
+				return newMount, errors.Wrapf(optionArgError, kv[0])
+			}
+			if err := ValidateVolumeCtrDir(kv[1]); err != nil {
+				return newMount, err
+			}
+			newMount.Destination = kv[1]
+			setDest = true
+		default:
+			return newMount, errors.Wrapf(util.ErrBadMntOption, kv[0])
+		}
+	}
+
+	if !setDest {
+		return newMount, noDestError
+	}
+
+	return newMount, nil
+}
+
+// Parse a single volume mount entry from the --mount flag.
+// Note that the volume-label option for named volumes is currently NOT supported.
+// TODO: add support for --volume-label
+func getNamedVolume(args []string) (*libpod.ContainerNamedVolume, error) {
+	newVolume := new(libpod.ContainerNamedVolume)
+
+	setSource := false
+	setDest := false
+
+	for _, val := range args {
+		kv := strings.Split(val, "=")
+		switch kv[0] {
+		case "ro", "nosuid", "nodev", "noexec":
+			// TODO: detect duplication of these options
+			newVolume.Options = append(newVolume.Options, kv[0])
+		case "volume-label":
+			return nil, errors.Errorf("the --volume-label option is not presently implemented")
+		case "src", "source":
+			if len(kv) == 1 {
+				return nil, errors.Wrapf(optionArgError, kv[0])
+			}
+			newVolume.Name = kv[1]
+			setSource = true
+		case "target", "dst", "destination":
+			if len(kv) == 1 {
+				return nil, errors.Wrapf(optionArgError, kv[0])
+			}
+			if err := ValidateVolumeCtrDir(kv[1]); err != nil {
+				return nil, err
+			}
+			newVolume.Dest = kv[1]
+			setDest = true
+		default:
+			return nil, errors.Wrapf(util.ErrBadMntOption, kv[0])
+		}
+	}
+
+	if !setSource {
+		return nil, errors.Errorf("must set source volume")
+	}
+	if !setDest {
+		return nil, noDestError
+	}
+
+	return newVolume, nil
+}
+
+// ValidateVolumeHostDir validates a volume mount's source directory
+func ValidateVolumeHostDir(hostDir string) error {
+	if len(hostDir) == 0 {
+		return errors.Errorf("host directory cannot be empty")
+	}
+	if filepath.IsAbs(hostDir) {
+		if _, err := os.Stat(hostDir); err != nil {
+			return errors.Wrapf(err, "error checking path %q", hostDir)
+		}
+	}
+	// If hostDir is not an absolute path, that means the user wants to create a
+	// named volume. This will be done later on in the code.
+	return nil
+}
+
+// ValidateVolumeCtrDir validates a volume mount's destination directory.
+func ValidateVolumeCtrDir(ctrDir string) error {
+	if len(ctrDir) == 0 {
+		return errors.Errorf("container directory cannot be empty")
+	}
+	if !filepath.IsAbs(ctrDir) {
+		return errors.Errorf("invalid container path %q, must be an absolute path", ctrDir)
+	}
+	return nil
+}
+
+// ValidateVolumeOpts validates a volume's options
+func ValidateVolumeOpts(options []string) error {
+	var foundRootPropagation, foundRWRO, foundLabelChange int
+	for _, opt := range options {
+		switch opt {
+		case "rw", "ro":
+			foundRWRO++
+			if foundRWRO > 1 {
+				return errors.Errorf("invalid options %q, can only specify 1 'rw' or 'ro' option", strings.Join(options, ", "))
+			}
+		case "z", "Z":
+			foundLabelChange++
+			if foundLabelChange > 1 {
+				return errors.Errorf("invalid options %q, can only specify 1 'z' or 'Z' option", strings.Join(options, ", "))
+			}
+		case "private", "rprivate", "shared", "rshared", "slave", "rslave":
+			foundRootPropagation++
+			if foundRootPropagation > 1 {
+				return errors.Errorf("invalid options %q, can only specify 1 '[r]shared', '[r]private' or '[r]slave' option", strings.Join(options, ", "))
+			}
+		default:
+			return errors.Errorf("invalid option type %q", opt)
+		}
+	}
+	return nil
+}
+
+// GetVolumeMounts takes user provided input for bind mounts and creates Mount structs
+func (config *CreateConfig) getVolumeMounts() (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+	mounts := make(map[string]spec.Mount)
+	volumes := make(map[string]*libpod.ContainerNamedVolume)
+
+	volumeFormatErr := errors.Errorf("incorrect volume format, should be host-dir:ctr-dir[:option]")
+
+	for _, vol := range config.Volumes {
+		var (
+			options []string
+			src     string
+			dest    string
+		)
+
+		splitVol := strings.Split(vol, ":")
+		if len(splitVol) > 3 {
+			return nil, nil, errors.Wrapf(volumeFormatErr, vol)
+		}
+
+		src = splitVol[0]
+		if len(splitVol) == 1 {
+			dest = src
+		} else if len(splitVol) > 1 {
+			dest = splitVol[1]
+		}
+		if len(splitVol) > 2 {
+			options = strings.Split(splitVol[2], ",")
+			if err := ValidateVolumeOpts(options); err != nil {
+				return nil, nil, err
+			}
+		}
+
+		if err := ValidateVolumeHostDir(src); err != nil {
+			return nil, nil, err
+		}
+		if err := ValidateVolumeCtrDir(dest); err != nil {
+			return nil, nil, err
+		}
+
+		if strings.HasPrefix(src, "/") || strings.HasPrefix(src, ".") {
+			// This is not a named volume
+			newMount := spec.Mount{
+				Destination: dest,
+				Type:        string(TypeBind),
+				Source:      src,
+				Options:     options,
+			}
+			if _, ok := mounts[newMount.Destination]; ok {
+				return nil, nil, errors.Wrapf(errDuplicateDest, newMount.Destination)
+			}
+			mounts[newMount.Destination] = newMount
+		} else {
+			// This is a named volume
+			newNamedVol := new(libpod.ContainerNamedVolume)
+			newNamedVol.Name = src
+			newNamedVol.Dest = dest
+			newNamedVol.Options = options
+
+			if _, ok := volumes[newNamedVol.Dest]; ok {
+				return nil, nil, errors.Wrapf(errDuplicateDest, newNamedVol.Dest)
+			}
+			volumes[newNamedVol.Dest] = newNamedVol
+		}
+
+		logrus.Debugf("User mount %s:%s options %v", src, dest, options)
+	}
+
+	return mounts, volumes, nil
+}
+
+// Get mounts for container's image volumes
+func (config *CreateConfig) getImageVolumes() (map[string]spec.Mount, map[string]*libpod.ContainerNamedVolume, error) {
+	mounts := make(map[string]spec.Mount)
+	volumes := make(map[string]*libpod.ContainerNamedVolume)
+
+	if config.ImageVolumeType == "ignore" {
+		return mounts, volumes, nil
+	}
+
+	for vol := range config.BuiltinImgVolumes {
+		if config.ImageVolumeType == "tmpfs" {
+			// Tmpfs image volumes are handled as mounts
+			mount := spec.Mount{
+				Destination: vol,
+				Source:      TypeTmpfs,
+				Type:        TypeTmpfs,
+				Options:     []string{"rprivate", "rw", "nodev"},
+			}
+			mounts[vol] = mount
+		} else {
+			namedVolume := new(libpod.ContainerNamedVolume)
+			namedVolume.Name = stringid.GenerateNonCryptoID()
+			namedVolume.Options = []string{"rprivate", "rw", "nodev"}
+			namedVolume.Dest = vol
+			volumes[vol] = namedVolume
+		}
+	}
+
+	return mounts, volumes, nil
+}
+
+// GetTmpfsMounts creates spec.Mount structs for user-requested tmpfs mounts
+func (config *CreateConfig) getTmpfsMounts() (map[string]spec.Mount, error) {
+	m := make(map[string]spec.Mount)
+	for _, i := range config.Tmpfs {
+		// Default options if nothing passed
+		var options []string
+		spliti := strings.Split(i, ":")
+		destPath := spliti[0]
+		if len(spliti) > 1 {
+			options = strings.Split(spliti[1], ",")
+		}
+
+		if _, ok := m[destPath]; ok {
+			return nil, errors.Wrapf(errDuplicateDest, destPath)
+		}
+
+		mount := spec.Mount{
+			Destination: destPath,
+			Type:        string(TypeTmpfs),
+			Options:     options,
+			Source:      string(TypeTmpfs),
+		}
+		m[destPath] = mount
+	}
+	return m, nil
+}
+
+// AddContainerInitBinary adds the init binary specified by path iff the
+// container will run in a private PID namespace that is not shared with the
+// host or another pre-existing container, where an init-like process is
+// already running.
+//
+// Note that AddContainerInitBinary prepends "/dev/init" "--" to the command
+// to execute the bind-mounted binary as PID 1.
+func (config *CreateConfig) addContainerInitBinary(path string) (spec.Mount, error) {
+	mount := spec.Mount{
+		Destination: "/dev/init",
+		Type:        TypeBind,
+		Source:      path,
+		Options:     []string{TypeBind, "ro"},
+	}
+
+	if path == "" {
+		return mount, fmt.Errorf("please specify a path to the container-init binary")
+	}
+	if !config.PidMode.IsPrivate() {
+		return mount, fmt.Errorf("cannot add init binary as PID 1 (PID namespace isn't private)")
+	}
+	if config.Systemd {
+		return mount, fmt.Errorf("cannot use container-init binary with systemd")
+	}
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return mount, errors.Wrap(err, "container-init binary not found on the host")
+	}
+	config.Command = append([]string{"/dev/init", "--"}, config.Command...)
+	return mount, nil
+}
+
+// Supercede existing mounts in the spec with new, user-specified mounts.
+// TODO: Should we unmount subtree mounts? E.g., if /tmp/ is mounted by
+// one mount, and we already have /tmp/a and /tmp/b, should we remove
+// the /tmp/a and /tmp/b mounts in favor of the more general /tmp?
+func supercedeUserMounts(mounts []spec.Mount, configMount []spec.Mount) []spec.Mount {
+	if len(mounts) > 0 {
+		// If we have overlappings mounts, remove them from the spec in favor of
+		// the user-added volume mounts
+		destinations := make(map[string]bool)
+		for _, mount := range mounts {
+			destinations[path.Clean(mount.Destination)] = true
+		}
+		// Copy all mounts from spec to defaultMounts, except for
+		//  - mounts overridden by a user supplied mount;
+		//  - all mounts under /dev if a user supplied /dev is present;
+		mountDev := destinations["/dev"]
+		for _, mount := range configMount {
+			if _, ok := destinations[path.Clean(mount.Destination)]; !ok {
+				if mountDev && strings.HasPrefix(mount.Destination, "/dev/") {
+					// filter out everything under /dev if /dev is user-mounted
+					continue
+				}
+
+				logrus.Debugf("Adding mount %s", mount.Destination)
+				mounts = append(mounts, mount)
+			}
+		}
+		return mounts
+	}
+	return configMount
+}
+
+// Ensure mount options on all mounts are correct
+func initFSMounts(inputMounts []spec.Mount) []spec.Mount {
+	var mounts []spec.Mount
+	for _, m := range inputMounts {
+		if m.Type == TypeBind {
+			m.Options = util.ProcessOptions(m.Options)
+		}
+		if m.Type == TypeTmpfs {
+			m.Options = append(m.Options, "tmpcopyup")
+		}
+		mounts = append(mounts, m)
+	}
+	return mounts
+}