diff options
Diffstat (limited to 'drivers/iommu/iommu-sva.c')
| -rw-r--r-- | drivers/iommu/iommu-sva.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c index c3fc9201d0be..65814cbc8402 100644 --- a/drivers/iommu/iommu-sva.c +++ b/drivers/iommu/iommu-sva.c @@ -41,6 +41,7 @@ static struct iommu_mm_data *iommu_alloc_mm_data(struct mm_struct *mm, struct de } iommu_mm->pasid = pasid; INIT_LIST_HEAD(&iommu_mm->sva_domains); + INIT_LIST_HEAD(&iommu_mm->sva_handles); /* * Make sure the write to mm->iommu_mm is not reordered in front of * initialization to iommu_mm fields. If it does, readers may see a @@ -82,6 +83,14 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm goto out_unlock; } + list_for_each_entry(handle, &mm->iommu_mm->sva_handles, handle_item) { + if (handle->dev == dev) { + refcount_inc(&handle->users); + mutex_unlock(&iommu_sva_lock); + return handle; + } + } + handle = kzalloc(sizeof(*handle), GFP_KERNEL); if (!handle) { ret = -ENOMEM; @@ -111,6 +120,8 @@ struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm list_add(&domain->next, &mm->iommu_mm->sva_domains); out: + refcount_set(&handle->users, 1); + list_add(&handle->handle_item, &mm->iommu_mm->sva_handles); mutex_unlock(&iommu_sva_lock); handle->dev = dev; handle->domain = domain; @@ -141,6 +152,12 @@ void iommu_sva_unbind_device(struct iommu_sva *handle) struct device *dev = handle->dev; mutex_lock(&iommu_sva_lock); + if (!refcount_dec_and_test(&handle->users)) { + mutex_unlock(&iommu_sva_lock); + return; + } + list_del(&handle->handle_item); + iommu_detach_device_pasid(domain, dev, iommu_mm->pasid); if (--domain->users == 0) { list_del(&domain->next); |