From 034d473109e90784868297870f456c9687f84058 Mon Sep 17 00:00:00 2001 From: Jacob Pan Date: Thu, 2 Jan 2020 08:18:10 +0800 Subject: [PATCH] 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 Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel --- drivers/iommu/intel-svm.c | 77 +++++++++++++++++++-------------------- 1 file changed, 38 insertions(+), 39 deletions(-) diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c index 7c6a6e8b1c96..04023033b79f 100644 --- a/drivers/iommu/intel-svm.c +++ b/drivers/iommu/intel-svm.c @@ -222,6 +222,10 @@ static const struct mmu_notifier_ops intel_mmuops = { static DEFINE_MUTEX(pasid_mutex); static LIST_HEAD(global_svm_list); +#define for_each_svm_dev(sdev, svm, d) \ + list_for_each_entry((sdev), &(svm)->devs, list) \ + if ((d) != (sdev)->dev) {} else + 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); @@ -270,15 +274,14 @@ 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; + /* Find the matching device in svm list */ + for_each_svm_dev(sdev, svm, dev) { + if (sdev->ops != ops) { + ret = -EBUSY; + goto out; } + sdev->users++; + goto success; } break; @@ -423,40 +426,36 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) 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); - kfree_rcu(sdev, rcu); + for_each_svm_dev(sdev, 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); + 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); - } + 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);