Re: [PATCH v11 11/14] crypto: iaa - Add support for deflate-iaa compression algorithm

[Tom Zanussi]

Hi Rex,

On Mon, 2023-12-04 at 23:00 +0800, Rex Zhang wrote:
> Hi, Tom,
> 
> On 2023-12-01 at 14:10:32 -0600, Tom Zanussi wrote:
> 
> [snip]
> 
> > +static int iaa_wq_put(struct idxd_wq *wq)
> > +{
> > +       struct idxd_device *idxd = wq->idxd;
> > +       struct iaa_wq *iaa_wq;
> > +       bool free = false;
> > +       int ret = 0;
> > +
> > +       spin_lock(&idxd->dev_lock);
> > +       iaa_wq = idxd_wq_get_private(wq);
> > +       if (iaa_wq) {
> > +               iaa_wq->ref--;
> > +               if (iaa_wq->ref == 0 && iaa_wq->remove) {
> > +                       __free_iaa_wq(iaa_wq);
> > +                       idxd_wq_set_private(wq, NULL);
> > +                       free = true;
> > +               }
> > +               idxd_wq_put(wq);
> > +       } else {
> > +               ret = -ENODEV;
> > +       }
> > +       spin_unlock(&idxd->dev_lock);
> __free_iaa_wq() may cause schedule, whether it should be move out of
> the
> context between spin_lock() and spin_unlock()?

Yeah, I suppose it makes more sense to have it below anyway, will move
it there.

> > +       if (free)
> > +               kfree(iaa_wq);
> > +
> > +       return ret;
> > +}
> 
> [snip]
> 
> > @@ -800,12 +1762,38 @@ static void iaa_crypto_remove(struct
> > idxd_dev *idxd_dev)
> >  
> >         remove_iaa_wq(wq);
> >  
> > +       spin_lock(&idxd->dev_lock);
> > +       iaa_wq = idxd_wq_get_private(wq);
> > +       if (!iaa_wq) {
> > +               spin_unlock(&idxd->dev_lock);
> > +               pr_err("%s: no iaa_wq available to remove\n",
> > __func__);
> > +               goto out;
> > +       }
> > +
> > +       if (iaa_wq->ref) {
> > +               iaa_wq->remove = true;
> > +       } else {
> > +               wq = iaa_wq->wq;
> > +               __free_iaa_wq(iaa_wq);
> > +               idxd_wq_set_private(wq, NULL);
> > +               free = true;
> > +       }
> > +       spin_unlock(&idxd->dev_lock);
> __free_iaa_wq() may cause schedule, whether it should be move out of
> the
> context between spin_lock() and spin_unlock()?

Same.

> > +
> > +       if (free)
> > +               kfree(iaa_wq);
> > +
> >         idxd_drv_disable_wq(wq);
> >         rebalance_wq_table();
> >  
> > -       if (nr_iaa == 0)
> > +       if (nr_iaa == 0) {
> > +               iaa_crypto_enabled = false;
> Is it necessary to add iaa_unregister_compression_device() here?
> All iaa devices are disabled cause the variable first_wq will be
> true,
> if enable wq, iaa_register_compression_device() will fail due to the
> algorithm is existed.

No, this is required by review input from a previous version - the
compression device can only be unregistered on module exit.

Thanks,

Tom

> >                 free_wq_table();
> > +               module_put(THIS_MODULE);
> >  
> > +               pr_info("iaa_crypto now DISABLED\n");
> > +       }
> > +out:
> >         mutex_unlock(&iaa_devices_lock);
> >         mutex_unlock(&wq->wq_lock);
> >  }
> 
> [snip]
> 
> Thanks,
> Rex Zhang
> > -- 
> > 2.34.1
> >