goto err_unlock;
}
- /* Try to upgrade the domain we have */
- if (idev->enforce_cache_coherency) {
- rc = iommufd_hw_pagetable_enforce_cc(hwpt);
- if (rc)
- goto err_unlock;
- }
-
rc = iopt_table_enforce_dev_resv_regions(&hwpt->ioas->iopt, idev->dev,
&idev->igroup->sw_msi_start);
if (rc)
{
struct iommufd_group *igroup = idev->igroup;
struct iommufd_hw_pagetable *old_hwpt;
- unsigned int num_devices = 0;
struct iommufd_device *cur;
+ unsigned int num_devices;
int rc;
mutex_lock(&idev->igroup->lock);
return NULL;
}
- /* Try to upgrade the domain we have */
- list_for_each_entry(cur, &igroup->device_list, group_item) {
- num_devices++;
- if (cur->enforce_cache_coherency) {
- rc = iommufd_hw_pagetable_enforce_cc(hwpt);
- if (rc)
- goto err_unlock;
- }
- }
-
old_hwpt = igroup->hwpt;
if (hwpt->ioas != old_hwpt->ioas) {
list_for_each_entry(cur, &igroup->device_list, group_item) {
igroup->hwpt = hwpt;
+ num_devices = list_count_nodes(&igroup->device_list);
/*
* Move the refcounts held by the device_list to the new hwpt. Retain a
* refcount for this thread as the caller will free it.
iommufd_hw_pagetable_destroy(obj);
}
-int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt)
+static int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt)
{
if (hwpt->enforce_cache_coherency)
return 0;
* doing any maps. It is an iommu driver bug to report
* IOMMU_CAP_ENFORCE_CACHE_COHERENCY but fail enforce_cache_coherency on
* a new domain.
+ *
+ * The cache coherency mode must be configured here and unchanged later.
+ * Note that a HWPT (non-CC) created for a device (non-CC) can be later
+ * reused by another device (either non-CC or CC). However, A HWPT (CC)
+ * created for a device (CC) cannot be reused by another device (non-CC)
+ * but only devices (CC). Instead user space in this case would need to
+ * allocate a separate HWPT (non-CC).
*/
if (idev->enforce_cache_coherency) {
rc = iommufd_hw_pagetable_enforce_cc(hwpt);
iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
struct iommufd_device *idev, u32 flags,
bool immediate_attach);
-int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt);
int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
struct iommufd_device *idev);
struct iommufd_hw_pagetable *