Hi

On 4/24/19 1:31 AM, Jacob Pan wrote:
> Use combined macro for_each_svm_dev() to simplify SVM device iteration.
> 
> Suggested-by: Andy Shevchenko <andriy.shevche...@linux.intel.com>
> Signed-off-by: Jacob Pan <jacob.jun....@linux.intel.com>
Reviewed-by: Eric Auger <eric.au...@redhat.com>

Thanks

Eric

> ---
>  drivers/iommu/intel-svm.c | 76 
> ++++++++++++++++++++++-------------------------
>  1 file changed, 36 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
> index 0a973c2..39dfb2e 100644
> --- a/drivers/iommu/intel-svm.c
> +++ b/drivers/iommu/intel-svm.c
> @@ -447,15 +447,13 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, 
> int flags, struct svm_dev_
>                               goto out;
>                       }
>  
> -                     list_for_each_entry(sdev, &svm->devs, list) {
> -                             if (dev == sdev->dev) {
> -                                     if (sdev->ops != ops) {
> -                                             ret = -EBUSY;
> -                                             goto out;
> -                                     }
> -                                     sdev->users++;
> -                                     goto success;
> +                     for_each_svm_dev() {
> +                             if (sdev->ops != ops) {
> +                                     ret = -EBUSY;
> +                                     goto out;
>                               }
> +                             sdev->users++;
> +                             goto success;
>                       }
>  
>                       break;
> @@ -585,40 +583,38 @@ int intel_svm_unbind_mm(struct device *dev, int pasid)
>       if (!svm)
>               goto out;
>  
> -     list_for_each_entry(sdev, &svm->devs, list) {
> -             if (dev == sdev->dev) {
> -                     ret = 0;
> -                     sdev->users--;
> -                     if (!sdev->users) {
> -                             list_del_rcu(&sdev->list);
> -                             /* Flush the PASID cache and IOTLB for this 
> device.
> -                              * Note that we do depend on the hardware *not* 
> using
> -                              * the PASID any more. Just as we depend on 
> other
> -                              * devices never using PASIDs that they have no 
> right
> -                              * to use. We have a *shared* PASID table, 
> because it's
> -                              * large and has to be physically contiguous. 
> So it's
> -                              * hard to be as defensive as we might like. */
> -                             intel_pasid_tear_down_entry(iommu, dev, 
> svm->pasid);
> -                             intel_flush_svm_range_dev(svm, sdev, 0, -1, 0, 
> !svm->mm);
> -                             kfree_rcu(sdev, rcu);
> -
> -                             if (list_empty(&svm->devs)) {
> -                                     ioasid_free(svm->pasid);
> -                                     if (svm->mm)
> -                                             
> mmu_notifier_unregister(&svm->notifier, svm->mm);
> -
> -                                     list_del(&svm->list);
> -
> -                                     /* We mandate that no page faults may 
> be outstanding
> -                                      * for the PASID when 
> intel_svm_unbind_mm() is called.
> -                                      * If that is not obeyed, subtle errors 
> will happen.
> -                                      * Let's make them less subtle... */
> -                                     memset(svm, 0x6b, sizeof(*svm));
> -                                     kfree(svm);
> -                             }
> +     for_each_svm_dev() {
> +             ret = 0;
> +             sdev->users--;
> +             if (!sdev->users) {
> +                     list_del_rcu(&sdev->list);
> +                     /* Flush the PASID cache and IOTLB for this device.
> +                      * Note that we do depend on the hardware *not* using
> +                      * the PASID any more. Just as we depend on other
> +                      * devices never using PASIDs that they have no right
> +                      * to use. We have a *shared* PASID table, because it's
> +                      * large and has to be physically contiguous. So it's
> +                      * hard to be as defensive as we might like. */
> +                     intel_pasid_tear_down_entry(iommu, dev, svm->pasid);
> +                     intel_flush_svm_range_dev(svm, sdev, 0, -1, 0, 
> !svm->mm);
> +                     kfree_rcu(sdev, rcu);
> +
> +                     if (list_empty(&svm->devs)) {
> +                             ioasid_free(svm->pasid);
> +                             if (svm->mm)
> +                                     mmu_notifier_unregister(&svm->notifier, 
> svm->mm);
> +
> +                             list_del(&svm->list);
> +
> +                             /* We mandate that no page faults may be 
> outstanding
> +                              * for the PASID when intel_svm_unbind_mm() is 
> called.
> +                              * If that is not obeyed, subtle errors will 
> happen.
> +                              * Let's make them less subtle... */
> +                             memset(svm, 0x6b, sizeof(*svm));
> +                             kfree(svm);
>                       }
> -                     break;
>               }
> +             break;
>       }
>   out:
>       mutex_unlock(&pasid_mutex);
> 
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