Re: [PATCH v5 16/19] iommu/vt-d: Misc macro clean up for SVM
On Fri, 16 Aug 2019 00:17:44 +0300 Andy Shevchenko wrote: > On Thu, Aug 15, 2019 at 11:52 PM Jacob Pan > wrote: > > > > Use combined macros for_each_svm_dev() to simplify SVM device > > iteration and error checking. > > > > Suggested-by: Andy Shevchenko > > Signed-off-by: Jacob Pan > > Reviewed-by: Eric Auger > > --- > > drivers/iommu/intel-svm.c | 85 > > +++ 1 file changed, 41 > > insertions(+), 44 deletions(-) > > > > diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c > > index 5a688a5..ea6f2e2 100644 > > --- a/drivers/iommu/intel-svm.c > > +++ b/drivers/iommu/intel-svm.c > > @@ -218,6 +218,10 @@ static const struct mmu_notifier_ops > > intel_mmuops = { static DEFINE_MUTEX(pasid_mutex); > > static LIST_HEAD(global_svm_list); > > > > +#define for_each_svm_dev(svm, dev) \ > > + list_for_each_entry(sdev, &svm->devs, list) \ > > > + if (dev == sdev->dev) \ > > This should be > if (dev != sdev->dev) {} else > and no trailing \ is neeeded. > > The rationale of above form to avoid > for_each_foo() { > } else { > ...WTF?!.. > } > I understand, but until we have the else {} case we don't have anything to avoid. The current code only has a simple positive logic. > > + > > int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, > > struct svm_dev_ops *ops) { > > struct intel_iommu *iommu = intel_svm_device_to_iommu(dev); > > @@ -263,15 +267,13 @@ 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(svm, dev) { > > + if (sdev->ops != ops) { > > + ret = -EBUSY; > > + goto out; > > } > > + sdev->users++; > > + goto success; > > } > > > > break; > > @@ -408,48 +410,43 @@ int intel_svm_unbind_mm(struct device *dev, > > int pasid) goto out; > > > > svm = ioasid_find(NULL, pasid, NULL); > > - if (IS_ERR(svm)) { > > + if (IS_ERR_OR_NULL(svm)) { > > ret = PTR_ERR(svm); > > goto out; > > } > > > > - if (!svm) > > - goto out; > > + for_each_svm_dev(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_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 > > -* lar
Re: [PATCH v5 16/19] iommu/vt-d: Misc macro clean up for SVM
On Thu, Aug 15, 2019 at 11:52 PM Jacob Pan wrote: > > Use combined macros for_each_svm_dev() to simplify SVM device iteration > and error checking. > > Suggested-by: Andy Shevchenko > Signed-off-by: Jacob Pan > Reviewed-by: Eric Auger > --- > drivers/iommu/intel-svm.c | 85 > +++ > 1 file changed, 41 insertions(+), 44 deletions(-) > > diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c > index 5a688a5..ea6f2e2 100644 > --- a/drivers/iommu/intel-svm.c > +++ b/drivers/iommu/intel-svm.c > @@ -218,6 +218,10 @@ static const struct mmu_notifier_ops intel_mmuops = { > static DEFINE_MUTEX(pasid_mutex); > static LIST_HEAD(global_svm_list); > > +#define for_each_svm_dev(svm, dev) \ > + list_for_each_entry(sdev, &svm->devs, list) \ > + if (dev == sdev->dev) \ This should be if (dev != sdev->dev) {} else and no trailing \ is neeeded. The rationale of above form to avoid for_each_foo() { } else { ...WTF?!.. } > + > int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct > svm_dev_ops *ops) > { > struct intel_iommu *iommu = intel_svm_device_to_iommu(dev); > @@ -263,15 +267,13 @@ 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(svm, dev) { > + if (sdev->ops != ops) { > + ret = -EBUSY; > + goto out; > } > + sdev->users++; > + goto success; > } > > break; > @@ -408,48 +410,43 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) > goto out; > > svm = ioasid_find(NULL, pasid, NULL); > - if (IS_ERR(svm)) { > + if (IS_ERR_OR_NULL(svm)) { > ret = PTR_ERR(svm); > goto out; > } > > - if (!svm) > - goto out; > + for_each_svm_dev(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_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); > - kfr
[PATCH v5 16/19] iommu/vt-d: Misc macro clean up for SVM
Use combined macros for_each_svm_dev() to simplify SVM device iteration and error checking. Suggested-by: Andy Shevchenko Signed-off-by: Jacob Pan Reviewed-by: Eric Auger --- drivers/iommu/intel-svm.c | 85 +++ 1 file changed, 41 insertions(+), 44 deletions(-) diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index 5a688a5..ea6f2e2 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -218,6 +218,10 @@ static const struct mmu_notifier_ops intel_mmuops = { static DEFINE_MUTEX(pasid_mutex); static LIST_HEAD(global_svm_list); +#define for_each_svm_dev(svm, dev) \ + list_for_each_entry(sdev, &svm->devs, list) \ + if (dev == sdev->dev) \ + int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ops *ops) { struct intel_iommu *iommu = intel_svm_device_to_iommu(dev); @@ -263,15 +267,13 @@ 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(svm, dev) { + if (sdev->ops != ops) { + ret = -EBUSY; + goto out; } + sdev->users++; + goto success; } break; @@ -408,48 +410,43 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) goto out; svm = ioasid_find(NULL, pasid, NULL); - if (IS_ERR(svm)) { + if (IS_ERR_OR_NULL(svm)) { ret = PTR_ERR(svm); goto out; } - if (!svm) - goto out; + for_each_svm_dev(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_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 tha