vfio/iommu_type1: Mantain a counter for non_pinned_groups

With this counter, we never need to traverse all groups to update
pinned_scope of vfio_iommu.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 78bd28873945a2078d93206864df42a3e0f32f2c..706b88b5d4ee8c43c71a9f53050f94e41e75bff7 100644 (file)
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -70,10 +70,10 @@ struct vfio_iommu {
        struct blocking_notifier_head notifier;
        unsigned int            dma_avail;
        uint64_t                pgsize_bitmap;
+       uint64_t                num_non_pinned_groups;
        bool                    v2;
        bool                    nesting;
        bool                    dirty_page_tracking;
-       bool                    pinned_page_dirty_scope;
 };
 
 struct vfio_domain {
@@ -148,7 +148,6 @@ static int put_pfn(unsigned long pfn, int prot);
 static struct vfio_group *vfio_iommu_find_iommu_group(struct vfio_iommu *iommu,
                                               struct iommu_group *iommu_group);
 
-static void update_pinned_page_dirty_scope(struct vfio_iommu *iommu);
 /*
  * This code handles mapping and unmapping of user data buffers
  * into DMA'ble space using the IOMMU
@@ -726,7 +725,7 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data,
        group = vfio_iommu_find_iommu_group(iommu, iommu_group);
        if (!group->pinned_page_dirty_scope) {
                group->pinned_page_dirty_scope = true;
-               update_pinned_page_dirty_scope(iommu);
+               iommu->num_non_pinned_groups--;
        }
 
        goto pin_done;
@@ -1004,7 +1003,7 @@ static int update_user_bitmap(u64 __user *bitmap, struct vfio_iommu *iommu,
         * mark all pages dirty if any IOMMU capable device is not able
         * to report dirty pages and all pages are pinned and mapped.
         */
-       if (!iommu->pinned_page_dirty_scope && dma->iommu_mapped)
+       if (iommu->num_non_pinned_groups && dma->iommu_mapped)
                bitmap_set(dma->bitmap, 0, nbits);
 
        if (shift) {
@@ -1635,33 +1634,6 @@ static struct vfio_group *vfio_iommu_find_iommu_group(struct vfio_iommu *iommu,
        return group;
 }
 
-static void update_pinned_page_dirty_scope(struct vfio_iommu *iommu)
-{
-       struct vfio_domain *domain;
-       struct vfio_group *group;
-
-       list_for_each_entry(domain, &iommu->domain_list, next) {
-               list_for_each_entry(group, &domain->group_list, next) {
-                       if (!group->pinned_page_dirty_scope) {
-                               iommu->pinned_page_dirty_scope = false;
-                               return;
-                       }
-               }
-       }
-
-       if (iommu->external_domain) {
-               domain = iommu->external_domain;
-               list_for_each_entry(group, &domain->group_list, next) {
-                       if (!group->pinned_page_dirty_scope) {
-                               iommu->pinned_page_dirty_scope = false;
-                               return;
-                       }
-               }
-       }
-
-       iommu->pinned_page_dirty_scope = true;
-}
-
 static bool vfio_iommu_has_sw_msi(struct list_head *group_resv_regions,
                                  phys_addr_t *base)
 {
@@ -2070,8 +2042,6 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
                         * addition of a dirty tracking group.
                         */
                        group->pinned_page_dirty_scope = true;
-                       if (!iommu->pinned_page_dirty_scope)
-                               update_pinned_page_dirty_scope(iommu);
                        mutex_unlock(&iommu->lock);
 
                        return 0;
@@ -2201,7 +2171,7 @@ done:
         * demotes the iommu scope until it declares itself dirty tracking
         * capable via the page pinning interface.
         */
-       iommu->pinned_page_dirty_scope = false;
+       iommu->num_non_pinned_groups++;
        mutex_unlock(&iommu->lock);
        vfio_iommu_resv_free(&group_resv_regions);
 
@@ -2414,7 +2384,7 @@ detach_group_done:
         * to be promoted.
         */
        if (update_dirty_scope) {
-               update_pinned_page_dirty_scope(iommu);
+               iommu->num_non_pinned_groups--;
                if (iommu->dirty_page_tracking)
                        vfio_iommu_populate_bitmap_full(iommu);
        }