When we want to promote the pinned_page_dirty_scope of vfio_iommu, we call the "update" function to visit all vfio_group, but when we want to downgrade this, we can set the flag as false directly.
So we'd better make an explicit "promote" semantic to the "update" function. BTW, if vfio_iommu already has been promoted, then return early. Signed-off-by: Keqian Zhu <[email protected]> --- drivers/vfio/vfio_iommu_type1.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 0b4dedaa9128..334a8240e1da 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -148,7 +148,7 @@ 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); +static void promote_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 @@ -714,7 +714,7 @@ 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); + promote_pinned_page_dirty_scope(iommu); } goto pin_done; @@ -1622,27 +1622,26 @@ 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) +static void promote_pinned_page_dirty_scope(struct vfio_iommu *iommu) { struct vfio_domain *domain; struct vfio_group *group; + if (iommu->pinned_page_dirty_scope) + return; + 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; + if (!group->pinned_page_dirty_scope) 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; + if (!group->pinned_page_dirty_scope) return; - } } } @@ -2057,8 +2056,7 @@ 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); + promote_pinned_page_dirty_scope(iommu); mutex_unlock(&iommu->lock); return 0; @@ -2341,7 +2339,7 @@ static void vfio_iommu_type1_detach_group(void *iommu_data, struct vfio_iommu *iommu = iommu_data; struct vfio_domain *domain; struct vfio_group *group; - bool update_dirty_scope = false; + bool promote_dirty_scope = false; LIST_HEAD(iova_copy); mutex_lock(&iommu->lock); @@ -2349,7 +2347,7 @@ static void vfio_iommu_type1_detach_group(void *iommu_data, if (iommu->external_domain) { group = find_iommu_group(iommu->external_domain, iommu_group); if (group) { - update_dirty_scope = !group->pinned_page_dirty_scope; + promote_dirty_scope = !group->pinned_page_dirty_scope; list_del(&group->next); kfree(group); @@ -2379,7 +2377,7 @@ static void vfio_iommu_type1_detach_group(void *iommu_data, continue; vfio_iommu_detach_group(domain, group); - update_dirty_scope = !group->pinned_page_dirty_scope; + promote_dirty_scope = !group->pinned_page_dirty_scope; list_del(&group->next); kfree(group); /* @@ -2415,8 +2413,8 @@ static void vfio_iommu_type1_detach_group(void *iommu_data, * Removal of a group without dirty tracking may allow the iommu scope * to be promoted. */ - if (update_dirty_scope) - update_pinned_page_dirty_scope(iommu); + if (promote_dirty_scope) + promote_pinned_page_dirty_scope(iommu); mutex_unlock(&iommu->lock); } -- 2.19.1
