From 19abcf70c2b16834a607db515b26a32b233c79eb Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Fri, 24 Jul 2020 09:49:22 +0800 Subject: iommu/vt-d: Add a helper to get svm and sdev for pasid There are several places in the code that need to get the pointers of svm and sdev according to a pasid and device. Add a helper to achieve this for code consolidation and readability. Signed-off-by: Lu Baolu Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20200724014925.15523-10-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel --- drivers/iommu/intel/svm.c | 115 ++++++++++++++++++++++++++-------------------- 1 file changed, 65 insertions(+), 50 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index 65d2327dcd0d..c104a50a625c 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -228,13 +228,57 @@ static LIST_HEAD(global_svm_list); list_for_each_entry((sdev), &(svm)->devs, list) \ if ((d) != (sdev)->dev) {} else +static int pasid_to_svm_sdev(struct device *dev, unsigned int pasid, + struct intel_svm **rsvm, + struct intel_svm_dev **rsdev) +{ + struct intel_svm_dev *d, *sdev = NULL; + struct intel_svm *svm; + + /* The caller should hold the pasid_mutex lock */ + if (WARN_ON(!mutex_is_locked(&pasid_mutex))) + return -EINVAL; + + if (pasid == INVALID_IOASID || pasid >= PASID_MAX) + return -EINVAL; + + svm = ioasid_find(NULL, pasid, NULL); + if (IS_ERR(svm)) + return PTR_ERR(svm); + + if (!svm) + goto out; + + /* + * If we found svm for the PASID, there must be at least one device + * bond. + */ + if (WARN_ON(list_empty(&svm->devs))) + return -EINVAL; + + rcu_read_lock(); + list_for_each_entry_rcu(d, &svm->devs, list) { + if (d->dev == dev) { + sdev = d; + break; + } + } + rcu_read_unlock(); + +out: + *rsvm = svm; + *rsdev = sdev; + + return 0; +} + int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev, struct iommu_gpasid_bind_data *data) { struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL); + struct intel_svm_dev *sdev = NULL; struct dmar_domain *dmar_domain; - struct intel_svm_dev *sdev; - struct intel_svm *svm; + struct intel_svm *svm = NULL; int ret = 0; if (WARN_ON(!iommu) || !data) @@ -261,35 +305,23 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev, dmar_domain = to_dmar_domain(domain); mutex_lock(&pasid_mutex); - svm = ioasid_find(NULL, data->hpasid, NULL); - if (IS_ERR(svm)) { - ret = PTR_ERR(svm); + ret = pasid_to_svm_sdev(dev, data->hpasid, &svm, &sdev); + if (ret) goto out; - } - - if (svm) { - /* - * If we found svm for the PASID, there must be at - * least one device bond, otherwise svm should be freed. - */ - if (WARN_ON(list_empty(&svm->devs))) { - ret = -EINVAL; - goto out; - } + if (sdev) { /* * Do not allow multiple bindings of the same device-PASID since * there is only one SL page tables per PASID. We may revisit * once sharing PGD across domains are supported. */ - for_each_svm_dev(sdev, svm, dev) { - dev_warn_ratelimited(dev, - "Already bound with PASID %u\n", - svm->pasid); - ret = -EBUSY; - goto out; - } - } else { + dev_warn_ratelimited(dev, "Already bound with PASID %u\n", + svm->pasid); + ret = -EBUSY; + goto out; + } + + if (!svm) { /* We come here when PASID has never been bond to a device. */ svm = kzalloc(sizeof(*svm), GFP_KERNEL); if (!svm) { @@ -372,25 +404,17 @@ int intel_svm_unbind_gpasid(struct device *dev, int pasid) struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL); struct intel_svm_dev *sdev; struct intel_svm *svm; - int ret = -EINVAL; + int ret; if (WARN_ON(!iommu)) return -EINVAL; mutex_lock(&pasid_mutex); - svm = ioasid_find(NULL, pasid, NULL); - if (!svm) { - ret = -EINVAL; - goto out; - } - - if (IS_ERR(svm)) { - ret = PTR_ERR(svm); + ret = pasid_to_svm_sdev(dev, pasid, &svm, &sdev); + if (ret) goto out; - } - for_each_svm_dev(sdev, svm, dev) { - ret = 0; + if (sdev) { if (iommu_dev_feature_enabled(dev, IOMMU_DEV_FEAT_AUX)) sdev->users--; if (!sdev->users) { @@ -414,7 +438,6 @@ int intel_svm_unbind_gpasid(struct device *dev, int pasid) kfree(svm); } } - break; } out: mutex_unlock(&pasid_mutex); @@ -592,7 +615,7 @@ success: if (sd) *sd = sdev; ret = 0; - out: +out: return ret; } @@ -608,17 +631,11 @@ static int intel_svm_unbind_mm(struct device *dev, int pasid) if (!iommu) goto out; - svm = ioasid_find(NULL, pasid, NULL); - if (!svm) - goto out; - - if (IS_ERR(svm)) { - ret = PTR_ERR(svm); + ret = pasid_to_svm_sdev(dev, pasid, &svm, &sdev); + if (ret) goto out; - } - for_each_svm_dev(sdev, svm, dev) { - ret = 0; + if (sdev) { sdev->users--; if (!sdev->users) { list_del_rcu(&sdev->list); @@ -647,10 +664,8 @@ static int intel_svm_unbind_mm(struct device *dev, int pasid) kfree(svm); } } - break; } - out: - +out: return ret; } -- cgit v1.2.3