iommu/vt-d: Add callback to device driver on page faults
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index 0e86542..006e95d 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -264,7 +264,7 @@
static DEFINE_MUTEX(pasid_mutex);
-int intel_svm_bind_mm(struct device *dev, int *pasid)
+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);
struct intel_svm_dev *sdev;
@@ -302,6 +302,10 @@
list_for_each_entry(sdev, &svm->devs, list) {
if (dev == sdev->dev) {
+ if (sdev->ops != ops) {
+ ret = -EBUSY;
+ goto out;
+ }
sdev->users++;
goto success;
}
@@ -327,6 +331,7 @@
}
/* Finish the setup now we know we're keeping it */
sdev->users = 1;
+ sdev->ops = ops;
init_rcu_head(&sdev->rcu);
if (!svm) {
@@ -456,6 +461,7 @@
tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK;
head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK;
while (head != tail) {
+ struct intel_svm_dev *sdev;
struct vm_area_struct *vma;
struct page_req_dsc *req;
struct qi_desc resp;
@@ -507,6 +513,24 @@
up_read(&svm->mm->mmap_sem);
bad_req:
/* Accounting for major/minor faults? */
+ rcu_read_lock();
+ list_for_each_entry_rcu(sdev, &svm->devs, list) {
+ if (sdev->sid == PCI_DEVID(req->bus, req->devfn));
+ break;
+ }
+ /* Other devices can go away, but the drivers are not permitted
+ * to unbind while any page faults might be in flight. So it's
+ * OK to drop the 'lock' here now we have it. */
+ rcu_read_unlock();
+
+ if (WARN_ON(&sdev->list == &svm->devs))
+ sdev = NULL;
+
+ if (sdev && sdev->ops && sdev->ops->fault_cb) {
+ int rwxp = (req->rd_req << 3) | (req->wr_req << 2) |
+ (req->wr_req << 1) | (req->exe_req);
+ sdev->ops->fault_cb(sdev->dev, req->pasid, req->addr, req->private, rwxp, result);
+ }
if (req->lpig) {
/* Page Group Response */