Drop ashmem and binder.

These are unfortunately unused and unmaintained. They can be brought back in
the future if need requires it.

PiperOrigin-RevId: 255697132

2 files changed, 0 insertions, 287 deletions

diff --git a/pkg/sentry/fs/binder/BUILD b/pkg/sentry/fs/binder/BUILD
deleted file mode 100644
index 639a5603a..000000000
--- a/pkg/sentry/fs/binder/BUILD
+++ /dev/null
@@ -1,27 +0,0 @@
-package(licenses = ["notice"])
-
-load("//tools/go_stateify:defs.bzl", "go_library")
-
-go_library(
-    name = "binder",
-    srcs = [
-        "binder.go",
-    ],
-    importpath = "gvisor.dev/gvisor/pkg/sentry/fs/binder",
-    visibility = ["//pkg/sentry:internal"],
-    deps = [
-        "//pkg/abi/linux",
-        "//pkg/sentry/arch",
-        "//pkg/sentry/context",
-        "//pkg/sentry/fs",
-        "//pkg/sentry/fs/fsutil",
-        "//pkg/sentry/kernel",
-        "//pkg/sentry/memmap",
-        "//pkg/sentry/pgalloc",
-        "//pkg/sentry/platform",
-        "//pkg/sentry/usage",
-        "//pkg/sentry/usermem",
-        "//pkg/syserror",
-        "//pkg/waiter",
-    ],
-)
diff --git a/pkg/sentry/fs/binder/binder.go b/pkg/sentry/fs/binder/binder.go
deleted file mode 100644
index eef54d787..000000000
--- a/pkg/sentry/fs/binder/binder.go
+++ /dev/null
@@ -1,260 +0,0 @@
-// Copyright 2018 The gVisor Authors.
-//
-// 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 binder implements Android Binder IPC module.
-package binder
-
-import (
-	"sync"
-
-	"gvisor.dev/gvisor/pkg/abi/linux"
-	"gvisor.dev/gvisor/pkg/sentry/arch"
-	"gvisor.dev/gvisor/pkg/sentry/context"
-	"gvisor.dev/gvisor/pkg/sentry/fs"
-	"gvisor.dev/gvisor/pkg/sentry/fs/fsutil"
-	"gvisor.dev/gvisor/pkg/sentry/kernel"
-	"gvisor.dev/gvisor/pkg/sentry/memmap"
-	"gvisor.dev/gvisor/pkg/sentry/pgalloc"
-	"gvisor.dev/gvisor/pkg/sentry/platform"
-	"gvisor.dev/gvisor/pkg/sentry/usage"
-	"gvisor.dev/gvisor/pkg/sentry/usermem"
-	"gvisor.dev/gvisor/pkg/syserror"
-	"gvisor.dev/gvisor/pkg/waiter"
-)
-
-const (
-	currentProtocolVersion = 8
-
-	// mmapSizeLimit is the upper limit for mapped memory size in Binder.
-	mmapSizeLimit = 4 * 1024 * 1024 // 4MB
-)
-
-// Device implements fs.InodeOperations.
-//
-// +stateify savable
-type Device struct {
-	fsutil.InodeGenericChecker       `state:"nosave"`
-	fsutil.InodeNoExtendedAttributes `state:"nosave"`
-	fsutil.InodeNoopAllocate         `state:"nosave"`
-	fsutil.InodeNoopRelease          `state:"nosave"`
-	fsutil.InodeNoopTruncate         `state:"nosave"`
-	fsutil.InodeNoopWriteOut         `state:"nosave"`
-	fsutil.InodeNotDirectory         `state:"nosave"`
-	fsutil.InodeNotMappable          `state:"nosave"`
-	fsutil.InodeNotSocket            `state:"nosave"`
-	fsutil.InodeNotSymlink           `state:"nosave"`
-	fsutil.InodeVirtual              `state:"nosave"`
-
-	fsutil.InodeSimpleAttributes
-}
-
-var _ fs.InodeOperations = (*Device)(nil)
-
-// NewDevice creates and initializes a Device structure.
-func NewDevice(ctx context.Context, owner fs.FileOwner, fp fs.FilePermissions) *Device {
-	return &Device{
-		InodeSimpleAttributes: fsutil.NewInodeSimpleAttributes(ctx, owner, fp, 0),
-	}
-}
-
-// GetFile implements fs.InodeOperations.GetFile.
-//
-// TODO(b/30946773): Add functionality to GetFile: Additional fields will be
-// needed in the Device structure, initialize them here. Also, Device will need
-// to keep track of the created Procs in order to implement BINDER_READ_WRITE
-// ioctl.
-func (bd *Device) GetFile(ctx context.Context, d *fs.Dirent, flags fs.FileFlags) (*fs.File, error) {
-	return fs.NewFile(ctx, d, flags, &Proc{
-		bd:   bd,
-		task: kernel.TaskFromContext(ctx),
-		mfp:  pgalloc.MemoryFileProviderFromContext(ctx),
-	}), nil
-}
-
-// Proc implements fs.FileOperations and fs.IoctlGetter.
-//
-// +stateify savable
-type Proc struct {
-	fsutil.FileNoFsync              `state:"nosave"`
-	fsutil.FileNoSplice             `state:"nosave"`
-	fsutil.FileNotDirReaddir        `state:"nosave"`
-	fsutil.FileUseInodeUnstableAttr `state:"nosave"`
-	waiter.AlwaysReady              `state:"nosave"`
-
-	bd   *Device
-	task *kernel.Task
-	mfp  pgalloc.MemoryFileProvider
-
-	// mu protects fr.
-	mu sync.Mutex `state:"nosave"`
-
-	// mapped is memory allocated from mfp.MemoryFile() by AddMapping.
-	mapped platform.FileRange
-}
-
-// Release implements fs.FileOperations.Release.
-func (bp *Proc) Release() {
-	bp.mu.Lock()
-	defer bp.mu.Unlock()
-	if bp.mapped.Length() != 0 {
-		bp.mfp.MemoryFile().DecRef(bp.mapped)
-	}
-}
-
-// Seek implements fs.FileOperations.Seek.
-//
-// Binder doesn't support seek operation (unless in debug mode).
-func (bp *Proc) Seek(ctx context.Context, file *fs.File, whence fs.SeekWhence, offset int64) (int64, error) {
-	return offset, syserror.EOPNOTSUPP
-}
-
-// Read implements fs.FileOperations.Read.
-//
-// Binder doesn't support read operation (unless in debug mode).
-func (bp *Proc) Read(ctx context.Context, file *fs.File, dst usermem.IOSequence, offset int64) (int64, error) {
-	return 0, syserror.EOPNOTSUPP
-}
-
-// Write implements fs.FileOperations.Write.
-//
-// Binder doesn't support write operation.
-func (bp *Proc) Write(ctx context.Context, file *fs.File, src usermem.IOSequence, offset int64) (int64, error) {
-	return 0, syserror.EOPNOTSUPP
-}
-
-// Flush implements fs.FileOperations.Flush.
-//
-// TODO(b/30946773): Implement.
-func (bp *Proc) Flush(ctx context.Context, file *fs.File) error {
-	return nil
-}
-
-// ConfigureMMap implements fs.FileOperations.ConfigureMMap.
-func (bp *Proc) ConfigureMMap(ctx context.Context, file *fs.File, opts *memmap.MMapOpts) error {
-	// Compare drivers/android/binder.c:binder_mmap().
-	if caller := kernel.TaskFromContext(ctx); caller != bp.task {
-		return syserror.EINVAL
-	}
-	if opts.Length > mmapSizeLimit {
-		opts.Length = mmapSizeLimit
-	}
-	opts.MaxPerms.Write = false
-
-	// TODO(b/30946773): Binder sets VM_DONTCOPY, preventing the created vma
-	// from being copied across fork(), but we don't support this yet. As
-	// a result, MMs containing a Binder mapping cannot be forked (MM.Fork will
-	// fail when AddMapping returns EBUSY).
-
-	return fsutil.GenericConfigureMMap(file, bp, opts)
-}
-
-// Ioctl implements fs.FileOperations.Ioctl.
-//
-// TODO(b/30946773): Implement.
-func (bp *Proc) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) {
-	// Switch on ioctl request.
-	switch uint32(args[1].Int()) {
-	case linux.BinderVersionIoctl:
-		ver := &linux.BinderVersion{
-			ProtocolVersion: currentProtocolVersion,
-		}
-		// Copy result to user-space.
-		_, err := usermem.CopyObjectOut(ctx, io, args[2].Pointer(), ver, usermem.IOOpts{
-			AddressSpaceActive: true,
-		})
-		return 0, err
-	case linux.BinderWriteReadIoctl:
-		// TODO(b/30946773): Implement.
-		fallthrough
-	case linux.BinderSetIdleTimeoutIoctl:
-		// TODO(b/30946773): Implement.
-		fallthrough
-	case linux.BinderSetMaxThreadsIoctl:
-		// TODO(b/30946773): Implement.
-		fallthrough
-	case linux.BinderSetIdlePriorityIoctl:
-		// TODO(b/30946773): Implement.
-		fallthrough
-	case linux.BinderSetContextMgrIoctl:
-		// TODO(b/30946773): Implement.
-		fallthrough
-	case linux.BinderThreadExitIoctl:
-		// TODO(b/30946773): Implement.
-		return 0, syserror.ENOSYS
-	default:
-		// Ioctls irrelevant to Binder.
-		return 0, syserror.EINVAL
-	}
-}
-
-// AddMapping implements memmap.Mappable.AddMapping.
-func (bp *Proc) AddMapping(ctx context.Context, ms memmap.MappingSpace, ar usermem.AddrRange, offset uint64, _ bool) error {
-	bp.mu.Lock()
-	defer bp.mu.Unlock()
-	if bp.mapped.Length() != 0 {
-		// mmap has been called before, which binder_mmap() doesn't like.
-		return syserror.EBUSY
-	}
-	// Binder only allocates and maps a single page up-front
-	// (drivers/android/binder.c:binder_mmap() => binder_update_page_range()).
-	fr, err := bp.mfp.MemoryFile().Allocate(usermem.PageSize, usage.Anonymous)
-	if err != nil {
-		return err
-	}
-	bp.mapped = fr
-	return nil
-}
-
-// RemoveMapping implements memmap.Mappable.RemoveMapping.
-func (*Proc) RemoveMapping(context.Context, memmap.MappingSpace, usermem.AddrRange, uint64, bool) {
-	// Nothing to do. Notably, we don't free bp.mapped to allow another mmap.
-}
-
-// CopyMapping implements memmap.Mappable.CopyMapping.
-func (bp *Proc) CopyMapping(ctx context.Context, ms memmap.MappingSpace, srcAR, dstAR usermem.AddrRange, offset uint64, _ bool) error {
-	// Nothing to do. Notably, this is one case where CopyMapping isn't
-	// equivalent to AddMapping, as AddMapping would return EBUSY.
-	return nil
-}
-
-// Translate implements memmap.Mappable.Translate.
-func (bp *Proc) Translate(ctx context.Context, required, optional memmap.MappableRange, at usermem.AccessType) ([]memmap.Translation, error) {
-	// TODO(b/30946773): In addition to the page initially allocated and mapped
-	// in AddMapping (Linux: binder_mmap), Binder allocates and maps pages for
-	// each transaction (Linux: binder_ioctl => binder_ioctl_write_read =>
-	// binder_thread_write => binder_transaction => binder_alloc_buf =>
-	// binder_update_page_range). Since we don't actually implement
-	// BinderWriteReadIoctl (Linux: BINDER_WRITE_READ), we only ever have the
-	// first page.
-	var err error
-	if required.End > usermem.PageSize {
-		err = &memmap.BusError{syserror.EFAULT}
-	}
-	if required.Start == 0 {
-		return []memmap.Translation{
-			{
-				Source: memmap.MappableRange{0, usermem.PageSize},
-				File:   bp.mfp.MemoryFile(),
-				Offset: bp.mapped.Start,
-				Perms:  usermem.AnyAccess,
-			},
-		}, err
-	}
-	return nil, err
-}
-
-// InvalidateUnsavable implements memmap.Mappable.InvalidateUnsavable.
-func (bp *Proc) InvalidateUnsavable(ctx context.Context) error {
-	return nil
-}