Remove fs.Handle, ramfs.Entry, and all the DeprecatedFileOperations.

More helper structs have been added to the fsutil package to make it easier to
implement fs.InodeOperations and fs.FileOperations.

PiperOrigin-RevId: 229305982
Change-Id: Ib6f8d3862f4216745116857913dbfa351530223b

5 files changed, 37 insertions, 266 deletions

diff --git a/pkg/sentry/fs/tty/BUILD b/pkg/sentry/fs/tty/BUILD
index 2b45069a6..011cb6955 100644
--- a/pkg/sentry/fs/tty/BUILD
+++ b/pkg/sentry/fs/tty/BUILD
@@ -7,7 +7,6 @@ go_library(
     srcs = [
         "dir.go",
         "fs.go",
-        "inode.go",
         "line_discipline.go",
         "master.go",
         "queue.go",
@@ -25,7 +24,6 @@ go_library(
         "//pkg/sentry/fs",
         "//pkg/sentry/fs/fsutil",
         "//pkg/sentry/kernel/auth",
-        "//pkg/sentry/kernel/time",
         "//pkg/sentry/socket/unix/transport",
         "//pkg/sentry/unimpl",
         "//pkg/sentry/usermem",
diff --git a/pkg/sentry/fs/tty/dir.go b/pkg/sentry/fs/tty/dir.go
index e32b05c1d..485cdb456 100644
--- a/pkg/sentry/fs/tty/dir.go
+++ b/pkg/sentry/fs/tty/dir.go
@@ -52,13 +52,17 @@ import (
 //
 // +stateify savable
 type dirInodeOperations struct {
-	fsutil.DeprecatedFileOperations  `state:"nosave"`
-	fsutil.InodeNotSocket            `state:"nosave"`
+	fsutil.InodeGenericChecker       `state:"nosave"`
+	fsutil.InodeNoExtendedAttributes `state:"nosave"`
+	fsutil.InodeNoopWriteOut         `state:"nosave"`
+	fsutil.InodeNotMappable          `state:"nosave"`
 	fsutil.InodeNotRenameable        `state:"nosave"`
 	fsutil.InodeNotSymlink           `state:"nosave"`
-	fsutil.InodeNoExtendedAttributes `state:"nosave"`
-	fsutil.NoMappable                `state:"nosave"`
-	fsutil.NoopWriteOut              `state:"nosave"`
+	fsutil.InodeNotSocket            `state:"nosave"`
+	fsutil.InodeNotTruncatable       `state:"nosave"`
+	fsutil.InodeVirtual              `state:"nosave"`
+
+	fsutil.InodeSimpleAttributes
 
 	// msrc is the super block this directory is on.
 	//
@@ -68,9 +72,6 @@ type dirInodeOperations struct {
 	// mu protects the fields below.
 	mu sync.Mutex `state:"nosave"`
 
-	// attr contains the UnstableAttrs.
-	attr fsutil.InMemoryAttributes
-
 	// master is the master PTY inode.
 	master *fs.Inode
 
@@ -97,15 +98,10 @@ var _ fs.InodeOperations = (*dirInodeOperations)(nil)
 // newDir creates a new dir with a ptmx file and no terminals.
 func newDir(ctx context.Context, m *fs.MountSource) *fs.Inode {
 	d := &dirInodeOperations{
-		attr: fsutil.InMemoryAttributes{
-			Unstable: fs.WithCurrentTime(ctx, fs.UnstableAttr{
-				Owner: fs.RootOwner,
-				Perms: fs.FilePermsFromMode(0555),
-			}),
-		},
-		msrc:      m,
-		slaves:    make(map[uint32]*fs.Inode),
-		dentryMap: fs.NewSortedDentryMap(nil),
+		InodeSimpleAttributes: fsutil.NewInodeSimpleAttributes(ctx, fs.RootOwner, fs.FilePermsFromMode(0555), linux.DEVPTS_SUPER_MAGIC),
+		msrc:                  m,
+		slaves:                make(map[uint32]*fs.Inode),
+		dentryMap:             fs.NewSortedDentryMap(nil),
 	}
 	// Linux devpts uses a default mode of 0000 for ptmx which can be
 	// changed with the ptmxmode mount option. However, that default is not
@@ -224,70 +220,6 @@ func (d *dirInodeOperations) GetFile(ctx context.Context, dirent *fs.Dirent, fla
 	return fs.NewFile(ctx, dirent, flags, &dirFileOperations{di: d}), nil
 }
 
-// UnstableAttr implements fs.InodeOperations.UnstableAttr.
-func (d *dirInodeOperations) UnstableAttr(ctx context.Context, inode *fs.Inode) (fs.UnstableAttr, error) {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	return d.attr.Unstable, nil
-}
-
-// Check implements fs.InodeOperations.Check.
-func (d *dirInodeOperations) Check(ctx context.Context, inode *fs.Inode, p fs.PermMask) bool {
-	return fs.ContextCanAccessFile(ctx, inode, p)
-}
-
-// SetPermissions implements fs.InodeOperations.SetPermissions.
-func (d *dirInodeOperations) SetPermissions(ctx context.Context, inode *fs.Inode, p fs.FilePermissions) bool {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	return d.attr.SetPermissions(ctx, p)
-}
-
-// SetOwner implements fs.InodeOperations.SetOwner.
-func (d *dirInodeOperations) SetOwner(ctx context.Context, inode *fs.Inode, owner fs.FileOwner) error {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	return d.attr.SetOwner(ctx, owner)
-}
-
-// SetTimestamps implements fs.InodeOperations.SetTimestamps.
-func (d *dirInodeOperations) SetTimestamps(ctx context.Context, inode *fs.Inode, ts fs.TimeSpec) error {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-	return d.attr.SetTimestamps(ctx, ts)
-}
-
-// Truncate implements fs.InodeOperations.Truncate.
-func (d *dirInodeOperations) Truncate(ctx context.Context, inode *fs.Inode, size int64) error {
-	return syserror.EINVAL
-}
-
-// AddLink implements fs.InodeOperations.AddLink.
-func (d *dirInodeOperations) AddLink() {}
-
-// DropLink implements fs.InodeOperations.DropLink.
-func (d *dirInodeOperations) DropLink() {}
-
-// NotifyStatusChange implements fs.InodeOperations.NotifyStatusChange.
-func (d *dirInodeOperations) NotifyStatusChange(ctx context.Context) {
-	d.mu.Lock()
-	defer d.mu.Unlock()
-
-	d.attr.TouchStatusChangeTime(ctx)
-}
-
-// IsVirtual implements fs.InodeOperations.IsVirtual.
-func (d *dirInodeOperations) IsVirtual() bool {
-	return true
-}
-
-// StatFS implements fs.InodeOperations.StatFS.
-func (d *dirInodeOperations) StatFS(ctx context.Context) (fs.Info, error) {
-	return fs.Info{
-		Type: linux.DEVPTS_SUPER_MAGIC,
-	}, nil
-}
-
 // allocateTerminal creates a new Terminal and installs a pts node for it.
 //
 // The caller must call DecRef when done with the returned Terminal.
@@ -353,13 +285,13 @@ func (d *dirInodeOperations) masterClose(t *Terminal) {
 //
 // +stateify savable
 type dirFileOperations struct {
-	waiter.AlwaysReady `state:"nosave"`
-	fsutil.NoopRelease `state:"nosave"`
-	fsutil.GenericSeek `state:"nosave"`
-	fsutil.NoFsync     `state:"nosave"`
-	fsutil.NoopFlush   `state:"nosave"`
-	fsutil.NoMMap      `state:"nosave"`
-	fsutil.NoIoctl     `state:"nosave"`
+	waiter.AlwaysReady     `state:"nosave"`
+	fsutil.FileNoopRelease `state:"nosave"`
+	fsutil.FileGenericSeek `state:"nosave"`
+	fsutil.FileNoFsync     `state:"nosave"`
+	fsutil.FileNoopFlush   `state:"nosave"`
+	fsutil.FileNoMMap      `state:"nosave"`
+	fsutil.FileNoIoctl     `state:"nosave"`
 
 	// di is the inode operations.
 	di *dirInodeOperations
diff --git a/pkg/sentry/fs/tty/inode.go b/pkg/sentry/fs/tty/inode.go
deleted file mode 100644
index d5d1caafc..000000000
--- a/pkg/sentry/fs/tty/inode.go
+++ /dev/null
@@ -1,145 +0,0 @@
-// Copyright 2018 Google LLC
-//
-// 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 tty
-
-import (
-	"sync"
-
-	"gvisor.googlesource.com/gvisor/pkg/abi/linux"
-	"gvisor.googlesource.com/gvisor/pkg/sentry/context"
-	"gvisor.googlesource.com/gvisor/pkg/sentry/fs"
-	"gvisor.googlesource.com/gvisor/pkg/sentry/fs/fsutil"
-	ktime "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/time"
-	"gvisor.googlesource.com/gvisor/pkg/syserror"
-)
-
-// inodeOperations are the base fs.InodeOperations for master and slave Inodes.
-//
-// inodeOperations does not implement:
-//
-// * fs.InodeOperations.Release
-// * fs.InodeOperations.GetFile
-//
-// +stateify savable
-type inodeOperations struct {
-	fsutil.DeprecatedFileOperations  `state:"nosave"`
-	fsutil.InodeNoExtendedAttributes `state:"nosave"`
-	fsutil.InodeNotDirectory         `state:"nosave"`
-	fsutil.InodeNotRenameable        `state:"nosave"`
-	fsutil.InodeNotSocket            `state:"nosave"`
-	fsutil.InodeNotSymlink           `state:"nosave"`
-	fsutil.NoMappable                `state:"nosave"`
-	fsutil.NoopWriteOut              `state:"nosave"`
-
-	// mu protects the fields below.
-	mu sync.Mutex `state:"nosave"`
-
-	// uattr is the inode's UnstableAttr.
-	uattr fs.UnstableAttr
-}
-
-// UnstableAttr implements fs.InodeOperations.UnstableAttr.
-func (i *inodeOperations) UnstableAttr(ctx context.Context, inode *fs.Inode) (fs.UnstableAttr, error) {
-	i.mu.Lock()
-	defer i.mu.Unlock()
-	return i.uattr, nil
-}
-
-// Check implements fs.InodeOperations.Check.
-func (i *inodeOperations) Check(ctx context.Context, inode *fs.Inode, p fs.PermMask) bool {
-	return fs.ContextCanAccessFile(ctx, inode, p)
-}
-
-// SetPermissions implements fs.InodeOperations.SetPermissions
-func (i *inodeOperations) SetPermissions(ctx context.Context, inode *fs.Inode, p fs.FilePermissions) bool {
-	i.mu.Lock()
-	defer i.mu.Unlock()
-	i.uattr.Perms = p
-	i.uattr.StatusChangeTime = ktime.NowFromContext(ctx)
-	return true
-}
-
-// SetOwner implements fs.InodeOperations.SetOwner.
-func (i *inodeOperations) SetOwner(ctx context.Context, inode *fs.Inode, owner fs.FileOwner) error {
-	i.mu.Lock()
-	defer i.mu.Unlock()
-	if owner.UID.Ok() {
-		i.uattr.Owner.UID = owner.UID
-	}
-	if owner.GID.Ok() {
-		i.uattr.Owner.GID = owner.GID
-	}
-	return nil
-}
-
-// SetTimestamps implements fs.InodeOperations.SetTimestamps.
-func (i *inodeOperations) SetTimestamps(ctx context.Context, inode *fs.Inode, ts fs.TimeSpec) error {
-	if ts.ATimeOmit && ts.MTimeOmit {
-		return nil
-	}
-
-	i.mu.Lock()
-	defer i.mu.Unlock()
-
-	now := ktime.NowFromContext(ctx)
-	if !ts.ATimeOmit {
-		if ts.ATime.IsZero() {
-			i.uattr.AccessTime = now
-		} else {
-			i.uattr.AccessTime = ts.ATime
-		}
-	}
-	if !ts.MTimeOmit {
-		if ts.MTime.IsZero() {
-			i.uattr.ModificationTime = now
-		} else {
-			i.uattr.ModificationTime = ts.MTime
-		}
-	}
-	i.uattr.StatusChangeTime = now
-	return nil
-}
-
-// Truncate implements fs.InodeOperations.Truncate.
-func (i *inodeOperations) Truncate(ctx context.Context, inode *fs.Inode, size int64) error {
-	return syserror.EINVAL
-}
-
-// AddLink implements fs.InodeOperations.AddLink.
-func (i *inodeOperations) AddLink() {
-}
-
-// DropLink implements fs.InodeOperations.DropLink.
-func (i *inodeOperations) DropLink() {
-}
-
-// NotifyStatusChange implements fs.InodeOperations.NotifyStatusChange.
-func (i *inodeOperations) NotifyStatusChange(ctx context.Context) {
-	i.mu.Lock()
-	defer i.mu.Unlock()
-	i.uattr.StatusChangeTime = ktime.NowFromContext(ctx)
-}
-
-// IsVirtual implements fs.InodeOperations.IsVirtual.
-func (i *inodeOperations) IsVirtual() bool {
-	return true
-}
-
-// StatFS implements fs.InodeOperations.StatFS.
-func (i *inodeOperations) StatFS(ctx context.Context) (fs.Info, error) {
-	return fs.Info{
-		Type: linux.DEVPTS_SUPER_MAGIC,
-	}, nil
-}
diff --git a/pkg/sentry/fs/tty/master.go b/pkg/sentry/fs/tty/master.go
index 00bec4c2c..b5e13ab36 100644
--- a/pkg/sentry/fs/tty/master.go
+++ b/pkg/sentry/fs/tty/master.go
@@ -31,7 +31,7 @@ import (
 //
 // +stateify savable
 type masterInodeOperations struct {
-	inodeOperations
+	fsutil.SimpleFileInode
 
 	// d is the containing dir.
 	d *dirInodeOperations
@@ -42,15 +42,8 @@ var _ fs.InodeOperations = (*masterInodeOperations)(nil)
 // newMasterInode creates an Inode for the master end of a terminal.
 func newMasterInode(ctx context.Context, d *dirInodeOperations, owner fs.FileOwner, p fs.FilePermissions) *fs.Inode {
 	iops := &masterInodeOperations{
-		inodeOperations: inodeOperations{
-			uattr: fs.WithCurrentTime(ctx, fs.UnstableAttr{
-				Owner: owner,
-				Perms: p,
-				Links: 1,
-				// Size and Blocks are always 0.
-			}),
-		},
-		d: d,
+		SimpleFileInode: *fsutil.NewSimpleFileInode(ctx, owner, p, linux.DEVPTS_SUPER_MAGIC),
+		d:               d,
 	}
 
 	return fs.NewInode(iops, d.msrc, fs.StableAttr{
@@ -102,11 +95,11 @@ func (mi *masterInodeOperations) GetFile(ctx context.Context, d *fs.Dirent, flag
 //
 // +stateify savable
 type masterFileOperations struct {
-	fsutil.PipeSeek      `state:"nosave"`
-	fsutil.NotDirReaddir `state:"nosave"`
-	fsutil.NoFsync       `state:"nosave"`
-	fsutil.NoopFlush     `state:"nosave"`
-	fsutil.NoMMap        `state:"nosave"`
+	fsutil.FilePipeSeek      `state:"nosave"`
+	fsutil.FileNotDirReaddir `state:"nosave"`
+	fsutil.FileNoFsync       `state:"nosave"`
+	fsutil.FileNoopFlush     `state:"nosave"`
+	fsutil.FileNoMMap        `state:"nosave"`
 
 	// d is the containing dir.
 	d *dirInodeOperations
diff --git a/pkg/sentry/fs/tty/slave.go b/pkg/sentry/fs/tty/slave.go
index a696fbb51..6dbce90b4 100644
--- a/pkg/sentry/fs/tty/slave.go
+++ b/pkg/sentry/fs/tty/slave.go
@@ -30,7 +30,7 @@ import (
 //
 // +stateify savable
 type slaveInodeOperations struct {
-	inodeOperations
+	fsutil.SimpleFileInode
 
 	// d is the containing dir.
 	d *dirInodeOperations
@@ -46,16 +46,9 @@ var _ fs.InodeOperations = (*slaveInodeOperations)(nil)
 // newSlaveInode takes ownership of t.
 func newSlaveInode(ctx context.Context, d *dirInodeOperations, t *Terminal, owner fs.FileOwner, p fs.FilePermissions) *fs.Inode {
 	iops := &slaveInodeOperations{
-		inodeOperations: inodeOperations{
-			uattr: fs.WithCurrentTime(ctx, fs.UnstableAttr{
-				Owner: owner,
-				Perms: p,
-				Links: 1,
-				// Size and Blocks are always 0.
-			}),
-		},
-		d: d,
-		t: t,
+		SimpleFileInode: *fsutil.NewSimpleFileInode(ctx, owner, p, linux.DEVPTS_SUPER_MAGIC),
+		d:               d,
+		t:               t,
 	}
 
 	return fs.NewInode(iops, d.msrc, fs.StableAttr{
@@ -91,11 +84,11 @@ func (si *slaveInodeOperations) GetFile(ctx context.Context, d *fs.Dirent, flags
 //
 // +stateify savable
 type slaveFileOperations struct {
-	fsutil.PipeSeek      `state:"nosave"`
-	fsutil.NotDirReaddir `state:"nosave"`
-	fsutil.NoFsync       `state:"nosave"`
-	fsutil.NoopFlush     `state:"nosave"`
-	fsutil.NoMMap        `state:"nosave"`
+	fsutil.FilePipeSeek      `state:"nosave"`
+	fsutil.FileNotDirReaddir `state:"nosave"`
+	fsutil.FileNoFsync       `state:"nosave"`
+	fsutil.FileNoopFlush     `state:"nosave"`
+	fsutil.FileNoMMap        `state:"nosave"`
 
 	// si is the inode operations.
 	si *slaveInodeOperations