It's common to iterate the svm device list and find a matched device. Add common helpers to do this and consolidate the code.
Signed-off-by: Lu Baolu <baolu...@linux.intel.com> Link: https://lore.kernel.org/r/20210520031531.712333-1-baolu...@linux.intel.com --- drivers/iommu/intel/svm.c | 68 +++++++++++++++++++++++---------------- 1 file changed, 40 insertions(+), 28 deletions(-) diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index da4310686ed3..57867ff97bc2 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -48,6 +48,40 @@ static void *pasid_private_find(ioasid_t pasid) return xa_load(&pasid_private_array, pasid); } +static struct intel_svm_dev * +svm_lookup_device_by_sid(struct intel_svm *svm, u16 sid) +{ + struct intel_svm_dev *sdev = NULL, *t; + + rcu_read_lock(); + list_for_each_entry_rcu(t, &svm->devs, list) { + if (t->sid == sid) { + sdev = t; + break; + } + } + rcu_read_unlock(); + + return sdev; +} + +static struct intel_svm_dev * +svm_lookup_device_by_dev(struct intel_svm *svm, struct device *dev) +{ + struct intel_svm_dev *sdev = NULL, *t; + + rcu_read_lock(); + list_for_each_entry_rcu(t, &svm->devs, list) { + if (t->dev == dev) { + sdev = t; + break; + } + } + rcu_read_unlock(); + + return sdev; +} + int intel_svm_enable_prq(struct intel_iommu *iommu) { struct page *pages; @@ -225,15 +259,11 @@ static const struct mmu_notifier_ops intel_mmuops = { static DEFINE_MUTEX(pasid_mutex); -#define for_each_svm_dev(sdev, svm, d) \ - 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_dev *sdev = NULL; struct intel_svm *svm; /* The caller should hold the pasid_mutex lock */ @@ -256,15 +286,7 @@ static int pasid_to_svm_sdev(struct device *dev, unsigned int pasid, */ 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(); + sdev = svm_lookup_device_by_dev(svm, dev); out: *rsvm = svm; @@ -533,7 +555,8 @@ static struct iommu_sva *intel_svm_bind_mm(struct intel_iommu *iommu, } /* Find the matching device in svm list */ - for_each_svm_dev(sdev, svm, dev) { + sdev = svm_lookup_device_by_dev(svm, dev); + if (sdev) { sdev->users++; goto success; } @@ -901,19 +924,8 @@ static irqreturn_t prq_event_thread(int irq, void *d) } } - if (!sdev || sdev->sid != req->rid) { - struct intel_svm_dev *t; - - sdev = NULL; - rcu_read_lock(); - list_for_each_entry_rcu(t, &svm->devs, list) { - if (t->sid == req->rid) { - sdev = t; - break; - } - } - rcu_read_unlock(); - } + if (!sdev || sdev->sid != req->rid) + sdev = svm_lookup_device_by_sid(svm, req->rid); /* Since we're using init_mm.pgd directly, we should never take * any faults on kernel addresses. */ -- 2.25.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
