On Thu, Mar 29, 2018 at 11:35:00PM +0100, Al Viro wrote:
> Uh-oh... What happens to existing users of kiocb_set_cancel_fn() now?
> AFAICS, those guys will *not* get aio_kiocb freed at all in case of
> io_cancel(2). Look: we mark them with AIO_IOCB_CANCELLED and
> call whatever ->ki_cancel() the d
On Thu, Mar 29, 2018 at 10:33:05PM +0200, Christoph Hellwig wrote:
> The upcoming aio poll support would like to be able to complete the
> iocb inline from the cancellation context, but that would cause a
> double lock of ctx_lock with the current locking scheme. Move the
> cancelation outside the
The upcoming aio poll support would like to be able to complete the
iocb inline from the cancellation context, but that would cause a
double lock of ctx_lock with the current locking scheme. Move the
cancelation outside the context lock to avoid this reversal, which
suits the existing usb gadgets
On Thu, Mar 29, 2018 at 03:25:06PM +0100, Al Viro wrote:
> OK. Let's leave that alone for now. Re deferred cancels - AFAICS, we *must*
> remove the sucker from ctx->active_reqs before dropping ->ctx_lock.
>
> As it is, you are creating a io_cancel()/io_cancel() race leading to double
> fput().
On Thu, Mar 29, 2018 at 10:53:05AM +0200, Christoph Hellwig wrote:
> On Wed, Mar 28, 2018 at 05:35:26PM +0100, Al Viro wrote:
> > > ret = vfs_fsync(req->file, req->datasync);
> > > - fput(req->file);
> > > - aio_complete(container_of(req, struct aio_kiocb, fsync), ret, 0);
> > > + if (aio_complet
On Wed, Mar 28, 2018 at 05:35:26PM +0100, Al Viro wrote:
> > ret = vfs_fsync(req->file, req->datasync);
> > - fput(req->file);
> > - aio_complete(container_of(req, struct aio_kiocb, fsync), ret, 0);
> > + if (aio_complete(iocb, ret, 0, 0))
> > + fput(file);
>
> IDGI.
> 1)
On Wed, Mar 28, 2018 at 05:35:26PM +0100, Al Viro wrote:
> On Wed, Mar 28, 2018 at 09:29:03AM +0200, Christoph Hellwig wrote:
> > static void aio_fsync_work(struct work_struct *work)
> > {
> > struct fsync_iocb *req = container_of(work, struct fsync_iocb, work);
> > + struct aio_kiocb *iocb
On Wed, Mar 28, 2018 at 09:29:03AM +0200, Christoph Hellwig wrote:
> static void aio_fsync_work(struct work_struct *work)
> {
> struct fsync_iocb *req = container_of(work, struct fsync_iocb, work);
> + struct aio_kiocb *iocb = container_of(req, struct aio_kiocb, fsync);
> + struct f
The upcoming aio poll support would like to be able to complete the
iocb inline from the cancellation context, but that would cause
a lock order reversal. Add support for optionally moving the cancelation
outside the context lock to avoid this reversal.
To make this safe aio_complete needs to che
