diff options
Diffstat (limited to 'pkg/sentry/fsimpl/tmpfs')
| -rw-r--r-- | pkg/sentry/fsimpl/tmpfs/filesystem.go | 6 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/tmpfs/regular_file.go | 29 |
2 files changed, 28 insertions, 7 deletions
diff --git a/pkg/sentry/fsimpl/tmpfs/filesystem.go b/pkg/sentry/fsimpl/tmpfs/filesystem.go index 71ac7b8e6..ed40f6b52 100644 --- a/pkg/sentry/fsimpl/tmpfs/filesystem.go +++ b/pkg/sentry/fsimpl/tmpfs/filesystem.go @@ -407,10 +407,10 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.Open case *regularFile: var fd regularFileFD fd.LockFD.Init(&d.inode.locks) - if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{AllowDirectIO: true}); err != nil { return nil, err } - if opts.Flags&linux.O_TRUNC != 0 { + if !afterCreate && opts.Flags&linux.O_TRUNC != 0 { if _, err := impl.truncate(0); err != nil { return nil, err } @@ -423,7 +423,7 @@ func (d *dentry) open(ctx context.Context, rp *vfs.ResolvingPath, opts *vfs.Open } var fd directoryFD fd.LockFD.Init(&d.inode.locks) - if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{}); err != nil { + if err := fd.vfsfd.Init(&fd, opts.Flags, rp.Mount(), &d.vfsd, &vfs.FileDescriptionOptions{AllowDirectIO: true}); err != nil { return nil, err } return &fd.vfsfd, nil diff --git a/pkg/sentry/fsimpl/tmpfs/regular_file.go b/pkg/sentry/fsimpl/tmpfs/regular_file.go index b805aadd0..1cdb46e6f 100644 --- a/pkg/sentry/fsimpl/tmpfs/regular_file.go +++ b/pkg/sentry/fsimpl/tmpfs/regular_file.go @@ -274,14 +274,32 @@ func (fd *regularFileFD) Release() { // noop } +// Allocate implements vfs.FileDescriptionImpl.Allocate. +func (fd *regularFileFD) Allocate(ctx context.Context, mode, offset, length uint64) error { + f := fd.inode().impl.(*regularFile) + + f.inode.mu.Lock() + defer f.inode.mu.Unlock() + oldSize := f.size + size := offset + length + if oldSize >= size { + return nil + } + _, err := f.truncateLocked(size) + return err +} + // PRead implements vfs.FileDescriptionImpl.PRead. func (fd *regularFileFD) PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts vfs.ReadOptions) (int64, error) { if offset < 0 { return 0, syserror.EINVAL } - // Check that flags are supported. Silently ignore RWF_HIPRI. - if opts.Flags&^linux.RWF_HIPRI != 0 { + // Check that flags are supported. RWF_DSYNC/RWF_SYNC can be ignored since + // all state is in-memory. + // + // TODO(gvisor.dev/issue/2601): Support select preadv2 flags. + if opts.Flags&^(linux.RWF_HIPRI|linux.RWF_DSYNC|linux.RWF_SYNC) != 0 { return 0, syserror.EOPNOTSUPP } @@ -311,8 +329,11 @@ func (fd *regularFileFD) PWrite(ctx context.Context, src usermem.IOSequence, off return 0, syserror.EINVAL } - // Check that flags are supported. Silently ignore RWF_HIPRI. - if opts.Flags&^linux.RWF_HIPRI != 0 { + // Check that flags are supported. RWF_DSYNC/RWF_SYNC can be ignored since + // all state is in-memory. + // + // TODO(gvisor.dev/issue/2601): Support select preadv2 flags. + if opts.Flags&^(linux.RWF_HIPRI|linux.RWF_DSYNC|linux.RWF_SYNC) != 0 { return 0, syserror.EOPNOTSUPP } |