diff options
Diffstat (limited to 'pkg/sentry/fs/dev/full.go')
-rw-r--r-- | pkg/sentry/fs/dev/full.go | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/pkg/sentry/fs/dev/full.go b/pkg/sentry/fs/dev/full.go new file mode 100644 index 000000000..8f6c6da2d --- /dev/null +++ b/pkg/sentry/fs/dev/full.go @@ -0,0 +1,81 @@ +// 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 dev + +import ( + "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" + "gvisor.googlesource.com/gvisor/pkg/sentry/usermem" + "gvisor.googlesource.com/gvisor/pkg/syserror" + "gvisor.googlesource.com/gvisor/pkg/waiter" +) + +// fullDevice is used to implement /dev/full. +// +// +stateify savable +type fullDevice 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 = (*fullDevice)(nil) + +func newFullDevice(ctx context.Context, owner fs.FileOwner, mode linux.FileMode) *fullDevice { + f := &fullDevice{ + InodeSimpleAttributes: fsutil.NewInodeSimpleAttributes(ctx, owner, fs.FilePermsFromMode(mode), linux.TMPFS_MAGIC), + } + return f +} + +// GetFile implements fs.InodeOperations.GetFile. +func (f *fullDevice) GetFile(ctx context.Context, dirent *fs.Dirent, flags fs.FileFlags) (*fs.File, error) { + flags.Pread = true + return fs.NewFile(ctx, dirent, flags, &fullFileOperations{}), nil +} + +// +stateify savable +type fullFileOperations struct { + waiter.AlwaysReady `state:"nosave"` + fsutil.FileGenericSeek `state:"nosave"` + fsutil.FileNoIoctl `state:"nosave"` + fsutil.FileNoMMap `state:"nosave"` + fsutil.FileNoopFlush `state:"nosave"` + fsutil.FileNoopFsync `state:"nosave"` + fsutil.FileNoopRelease `state:"nosave"` + fsutil.FileNotDirReaddir `state:"nosave"` + fsutil.FileUseInodeUnstableAttr `state:"nosave"` + fsutil.FileNoSplice `state:"nosave"` + readZeros `state:"nosave"` +} + +var _ fs.FileOperations = (*fullFileOperations)(nil) + +// Write implements FileOperations.Write. +func (*fullFileOperations) Write(context.Context, *fs.File, usermem.IOSequence, int64) (int64, error) { + return 0, syserror.ENOSPC +} |