From 18cb3d24cb3b59da11ebeac444021346495c95e4 Mon Sep 17 00:00:00 2001 From: Fabricio Voznika Date: Wed, 13 May 2020 10:30:00 -0700 Subject: Use VFS2 mount names Updates #1487 PiperOrigin-RevId: 311356385 --- runsc/boot/fs.go | 62 ++++++++++++++++++++------------------- runsc/boot/vfs.go | 87 ++++++++++++------------------------------------------- 2 files changed, 50 insertions(+), 99 deletions(-) diff --git a/runsc/boot/fs.go b/runsc/boot/fs.go index 4875452e2..8df5cc989 100644 --- a/runsc/boot/fs.go +++ b/runsc/boot/fs.go @@ -37,6 +37,12 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/gofer" "gvisor.dev/gvisor/pkg/sentry/fs/ramfs" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/devtmpfs" + gofervfs2 "gvisor.dev/gvisor/pkg/sentry/fsimpl/gofer" + procvfs2 "gvisor.dev/gvisor/pkg/sentry/fsimpl/proc" + sysvfs2 "gvisor.dev/gvisor/pkg/sentry/fsimpl/sys" + tmpfsvfs2 "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/syserror" @@ -44,23 +50,15 @@ import ( ) const ( - // Filesystem name for 9p gofer mounts. - rootFsName = "9p" - // Device name for root mount. rootDevice = "9pfs-/" // MountPrefix is the annotation prefix for mount hints. MountPrefix = "dev.gvisor.spec.mount." - // Filesystems that runsc supports. - bind = "bind" - devpts = "devpts" - devtmpfs = "devtmpfs" - proc = "proc" - sysfs = "sysfs" - tmpfs = "tmpfs" - nonefs = "none" + // Supported filesystems that map to different internal filesystem. + bind = "bind" + nonefs = "none" ) // tmpfs has some extra supported options that we must pass through. @@ -108,12 +106,12 @@ func compileMounts(spec *specs.Spec) []specs.Mount { // Always mount /dev. mounts = append(mounts, specs.Mount{ - Type: devtmpfs, + Type: devtmpfs.Name, Destination: "/dev", }) mounts = append(mounts, specs.Mount{ - Type: devpts, + Type: devpts.Name, Destination: "/dev/pts", }) @@ -137,13 +135,13 @@ func compileMounts(spec *specs.Spec) []specs.Mount { var mandatoryMounts []specs.Mount if !procMounted { mandatoryMounts = append(mandatoryMounts, specs.Mount{ - Type: proc, + Type: procvfs2.Name, Destination: "/proc", }) } if !sysMounted { mandatoryMounts = append(mandatoryMounts, specs.Mount{ - Type: sysfs, + Type: sysvfs2.Name, Destination: "/sys", }) } @@ -156,12 +154,16 @@ func compileMounts(spec *specs.Spec) []specs.Mount { } // p9MountOptions creates a slice of options for a p9 mount. -func p9MountOptions(fd int, fa FileAccessType) []string { +func p9MountOptions(fd int, fa FileAccessType, vfs2 bool) []string { opts := []string{ "trans=fd", "rfdno=" + strconv.Itoa(fd), "wfdno=" + strconv.Itoa(fd), - "privateunixsocket=true", + } + if !vfs2 { + // privateunixsocket is always enabled in VFS2. VFS1 requires explicit + // enablement. + opts = append(opts, "privateunixsocket=true") } if fa == FileAccessShared { opts = append(opts, "cache=remote_revalidating") @@ -234,7 +236,7 @@ func isSupportedMountFlag(fstype, opt string) bool { case "rw", "ro", "noatime", "noexec": return true } - if fstype == tmpfs { + if fstype == tmpfsvfs2.Name { ok, err := parseMountOption(opt, tmpfsAllowedOptions...) return ok && err == nil } @@ -444,7 +446,7 @@ func (m *mountHint) setOptions(val string) error { } func (m *mountHint) isSupported() bool { - return m.mount.Type == tmpfs && m.share == pod + return m.mount.Type == tmpfsvfs2.Name && m.share == pod } // checkCompatible verifies that shared mount is compatible with master. @@ -586,7 +588,7 @@ func (c *containerMounter) processHints(conf *Config) error { for _, hint := range c.hints.mounts { // TODO(b/142076984): Only support tmpfs for now. Bind mounts require a // common gofer to mount all shared volumes. - if hint.mount.Type != tmpfs { + if hint.mount.Type != tmpfsvfs2.Name { continue } log.Infof("Mounting master of shared mount %q from %q type %q", hint.name, hint.mount.Source, hint.mount.Type) @@ -723,7 +725,7 @@ func (c *containerMounter) createRootMount(ctx context.Context, conf *Config) (* fd := c.fds.remove() log.Infof("Mounting root over 9P, ioFD: %d", fd) p9FS := mustFindFilesystem("9p") - opts := p9MountOptions(fd, conf.FileAccess) + opts := p9MountOptions(fd, conf.FileAccess, false /* vfs2 */) if conf.OverlayfsStaleRead { // We can't check for overlayfs here because sandbox is chroot'ed and gofer @@ -779,11 +781,11 @@ func (c *containerMounter) getMountNameAndOptions(conf *Config, m specs.Mount) ( } switch m.Type { - case devpts, devtmpfs, proc, sysfs: + case devpts.Name, devtmpfs.Name, procvfs2.Name, sysvfs2.Name: fsName = m.Type case nonefs: - fsName = sysfs - case tmpfs: + fsName = sysvfs2.Name + case tmpfsvfs2.Name: fsName = m.Type var err error @@ -794,8 +796,8 @@ func (c *containerMounter) getMountNameAndOptions(conf *Config, m specs.Mount) ( case bind: fd := c.fds.remove() - fsName = "9p" - opts = p9MountOptions(fd, c.getMountAccessType(m)) + fsName = gofervfs2.Name + opts = p9MountOptions(fd, c.getMountAccessType(m), conf.VFS2) // If configured, add overlay to all writable mounts. useOverlay = conf.Overlay && !mountFlags(m.Options).ReadOnly @@ -948,7 +950,7 @@ func (c *containerMounter) createRestoreEnvironment(conf *Config) (*fs.RestoreEn // Add root mount. fd := c.fds.remove() - opts := p9MountOptions(fd, conf.FileAccess) + opts := p9MountOptions(fd, conf.FileAccess, false /* vfs2 */) mf := fs.MountSourceFlags{} if c.root.Readonly || conf.Overlay { @@ -960,7 +962,7 @@ func (c *containerMounter) createRestoreEnvironment(conf *Config) (*fs.RestoreEn Flags: mf, DataString: strings.Join(opts, ","), } - renv.MountSources[rootFsName] = append(renv.MountSources[rootFsName], rootMount) + renv.MountSources[gofervfs2.Name] = append(renv.MountSources[gofervfs2.Name], rootMount) // Add submounts. var tmpMounted bool @@ -976,7 +978,7 @@ func (c *containerMounter) createRestoreEnvironment(conf *Config) (*fs.RestoreEn // TODO(b/67958150): handle '/tmp' properly (see mountTmp()). if !tmpMounted { tmpMount := specs.Mount{ - Type: tmpfs, + Type: tmpfsvfs2.Name, Destination: "/tmp", } if err := c.addRestoreMount(conf, renv, tmpMount); err != nil { @@ -1032,7 +1034,7 @@ func (c *containerMounter) mountTmp(ctx context.Context, conf *Config, mns *fs.M // No '/tmp' found (or fallthrough from above). Safe to mount internal // tmpfs. tmpMount := specs.Mount{ - Type: tmpfs, + Type: tmpfsvfs2.Name, Destination: "/tmp", // Sticky bit is added to prevent accidental deletion of files from // another user. This is normally done for /tmp. diff --git a/runsc/boot/vfs.go b/runsc/boot/vfs.go index ef95d0c65..7378fbc95 100644 --- a/runsc/boot/vfs.go +++ b/runsc/boot/vfs.go @@ -18,7 +18,6 @@ import ( "fmt" "path" "sort" - "strconv" "strings" specs "github.com/opencontainers/runtime-spec/specs-go" @@ -26,12 +25,12 @@ import ( "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/sentry/devices/memdev" "gvisor.dev/gvisor/pkg/sentry/fs" - devpts2 "gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts" - devtmpfsimpl "gvisor.dev/gvisor/pkg/sentry/fsimpl/devtmpfs" - goferimpl "gvisor.dev/gvisor/pkg/sentry/fsimpl/gofer" - procimpl "gvisor.dev/gvisor/pkg/sentry/fsimpl/proc" - sysimpl "gvisor.dev/gvisor/pkg/sentry/fsimpl/sys" - tmpfsimpl "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/devtmpfs" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/gofer" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/proc" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/sys" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/context" @@ -42,28 +41,28 @@ import ( ) func registerFilesystems(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials) error { - vfsObj.MustRegisterFilesystemType(devpts2.Name, &devpts2.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + vfsObj.MustRegisterFilesystemType(devpts.Name, &devpts.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserList: true, // TODO(b/29356795): Users may mount this once the terminals are in a // usable state. AllowUserMount: false, }) - vfsObj.MustRegisterFilesystemType(devtmpfsimpl.Name, &devtmpfsimpl.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + vfsObj.MustRegisterFilesystemType(devtmpfs.Name, &devtmpfs.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserMount: true, AllowUserList: true, }) - vfsObj.MustRegisterFilesystemType(goferimpl.Name, &goferimpl.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + vfsObj.MustRegisterFilesystemType(gofer.Name, &gofer.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserList: true, }) - vfsObj.MustRegisterFilesystemType(procimpl.Name, &procimpl.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + vfsObj.MustRegisterFilesystemType(proc.Name, &proc.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserMount: true, AllowUserList: true, }) - vfsObj.MustRegisterFilesystemType(sysimpl.Name, &sysimpl.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + vfsObj.MustRegisterFilesystemType(sys.Name, &sys.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserMount: true, AllowUserList: true, }) - vfsObj.MustRegisterFilesystemType(tmpfsimpl.Name, &tmpfsimpl.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ + vfsObj.MustRegisterFilesystemType(tmpfs.Name, &tmpfs.FilesystemType{}, &vfs.RegisterFilesystemTypeOptions{ AllowUserMount: true, AllowUserList: true, }) @@ -72,7 +71,7 @@ func registerFilesystems(ctx context.Context, vfsObj *vfs.VirtualFilesystem, cre if err := memdev.Register(vfsObj); err != nil { return fmt.Errorf("registering memdev: %w", err) } - a, err := devtmpfsimpl.NewAccessor(ctx, vfsObj, creds, devtmpfsimpl.Name) + a, err := devtmpfs.NewAccessor(ctx, vfsObj, creds, devtmpfs.Name) if err != nil { return fmt.Errorf("creating devtmpfs accessor: %w", err) } @@ -193,10 +192,10 @@ func (c *containerMounter) setupVFS2(ctx context.Context, conf *Config, procArgs func (c *containerMounter) createMountNamespaceVFS2(ctx context.Context, conf *Config, creds *auth.Credentials) (*vfs.MountNamespace, error) { fd := c.fds.remove() - opts := strings.Join(p9MountOptionsVFS2(fd, conf.FileAccess), ",") + opts := strings.Join(p9MountOptions(fd, conf.FileAccess, true /* vfs2 */), ",") log.Infof("Mounting root over 9P, ioFD: %d", fd) - mns, err := c.k.VFS().NewMountNamespace(ctx, creds, "", rootFsName, &vfs.GetFilesystemOptions{Data: opts}) + mns, err := c.k.VFS().NewMountNamespace(ctx, creds, "", gofer.Name, &vfs.GetFilesystemOptions{Data: opts}) if err != nil { return nil, fmt.Errorf("setting up mount namespace: %w", err) } @@ -223,7 +222,8 @@ func (c *containerMounter) prepareMountsVFS2() { sort.Slice(c.mounts, func(i, j int) bool { return len(c.mounts[i].Destination) < len(c.mounts[j].Destination) }) } -// TODO(gvisor.dev/issue/1487): Implement submount options similar to the VFS1 version. +// TODO(gvisor.dev/issue/1487): Implement submount options similar to the VFS1 +// version. func (c *containerMounter) mountSubmountVFS2(ctx context.Context, conf *Config, mns *vfs.MountNamespace, creds *auth.Credentials, submount *specs.Mount) error { root := mns.Root() defer root.DecRef() @@ -233,7 +233,7 @@ func (c *containerMounter) mountSubmountVFS2(ctx context.Context, conf *Config, Path: fspath.Parse(submount.Destination), } - fsName, options, useOverlay, err := c.getMountNameAndOptionsVFS2(conf, *submount) + fsName, options, useOverlay, err := c.getMountNameAndOptions(conf, *submount) if err != nil { return fmt.Errorf("mountOptions failed: %w", err) } @@ -263,57 +263,6 @@ func (c *containerMounter) mountSubmountVFS2(ctx context.Context, conf *Config, return nil } -// getMountNameAndOptionsVFS2 retrieves the fsName, opts, and useOverlay values -// used for mounts. -func (c *containerMounter) getMountNameAndOptionsVFS2(conf *Config, m specs.Mount) (string, []string, bool, error) { - var ( - fsName string - opts []string - useOverlay bool - ) - - switch m.Type { - case devpts, devtmpfs, proc, sysfs: - fsName = m.Type - case nonefs: - fsName = sysfs - case tmpfs: - fsName = m.Type - - var err error - opts, err = parseAndFilterOptions(m.Options, tmpfsAllowedOptions...) - if err != nil { - return "", nil, false, err - } - - case bind: - fd := c.fds.remove() - fsName = "9p" - opts = p9MountOptionsVFS2(fd, c.getMountAccessType(m)) - // If configured, add overlay to all writable mounts. - useOverlay = conf.Overlay && !mountFlags(m.Options).ReadOnly - - default: - log.Warningf("ignoring unknown filesystem type %q", m.Type) - } - return fsName, opts, useOverlay, nil -} - -// p9MountOptions creates a slice of options for a p9 mount. -// TODO(gvisor.dev/issue/1624): Remove this version once privateunixsocket is -// deleted, along with the rest of VFS1. -func p9MountOptionsVFS2(fd int, fa FileAccessType) []string { - opts := []string{ - "trans=fd", - "rfdno=" + strconv.Itoa(fd), - "wfdno=" + strconv.Itoa(fd), - } - if fa == FileAccessShared { - opts = append(opts, "cache=remote_revalidating") - } - return opts -} - func (c *containerMounter) makeSyntheticMount(ctx context.Context, currentPath string, root vfs.VirtualDentry, creds *auth.Credentials) error { target := &vfs.PathOperation{ Root: root, -- cgit v1.2.3