Get a copy of iova list on _group_detach and try to update the list. On success replace the current one with the copy. Leave the list as it is if update fails.
Signed-off-by: Shameer Kolothum <[email protected]> --- drivers/vfio/vfio_iommu_type1.c | 103 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 103 insertions(+) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 4db87a9..8d8ddd7 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -1646,12 +1646,96 @@ static void vfio_sanity_check_pfn_list(struct vfio_iommu *iommu) WARN_ON(iommu->notifier.head); } +/* + * Called when a domain is removed in detach. It is possible that + * the removed domain decided the iova aperture window. Modify the + * iova aperture with the smallest window among existing domains. + */ +static void vfio_iommu_aper_expand(struct vfio_iommu *iommu, + struct list_head *iova_copy) +{ + struct vfio_domain *domain; + struct iommu_domain_geometry geo; + struct vfio_iova *node; + phys_addr_t start = 0; + phys_addr_t end = (phys_addr_t)~0; + + list_for_each_entry(domain, &iommu->domain_list, next) { + iommu_domain_get_attr(domain->domain, DOMAIN_ATTR_GEOMETRY, + &geo); + if (geo.aperture_start > start) + start = geo.aperture_start; + if (geo.aperture_end < end) + end = geo.aperture_end; + } + + /* Modify aperture limits. The new aper is either same or bigger */ + node = list_first_entry(iova_copy, struct vfio_iova, list); + node->start = start; + node = list_last_entry(iova_copy, struct vfio_iova, list); + node->end = end; +} + +/* + * Called when a group is detached. The reserved regions for that + * group can be part of valid iova now. But since reserved regions + * may be duplicated among groups, populate the iova valid regions + * list again. + */ +static int vfio_iommu_resv_refresh(struct vfio_iommu *iommu, + struct list_head *iova_copy) +{ + struct vfio_domain *d; + struct vfio_group *g; + struct vfio_iova *node, *tmp; + struct iommu_resv_region *resv, *resv_next; + struct list_head resv_regions; + phys_addr_t start, end; + int ret; + + INIT_LIST_HEAD(&resv_regions); + + list_for_each_entry(d, &iommu->domain_list, next) { + list_for_each_entry(g, &d->group_list, next) + iommu_get_group_resv_regions(g->iommu_group, + &resv_regions); + } + + if (list_empty(&resv_regions)) + return 0; + + node = list_first_entry(iova_copy, struct vfio_iova, list); + start = node->start; + node = list_last_entry(iova_copy, struct vfio_iova, list); + end = node->end; + + /* purge the iova list and create new one */ + list_for_each_entry_safe(node, tmp, iova_copy, list) { + list_del(&node->list); + kfree(node); + } + + ret = vfio_iommu_aper_resize(iova_copy, start, end); + if (ret) + goto done; + + /* Exclude current reserved regions from iova ranges */ + ret = vfio_iommu_resv_exclude(iova_copy, &resv_regions); +done: + list_for_each_entry_safe(resv, resv_next, &resv_regions, list) + kfree(resv); + return ret; +} + static void vfio_iommu_type1_detach_group(void *iommu_data, struct iommu_group *iommu_group) { struct vfio_iommu *iommu = iommu_data; struct vfio_domain *domain; struct vfio_group *group; + struct list_head iova_copy; + struct vfio_iova *iova, *iova_next; + bool iova_copy_fail; mutex_lock(&iommu->lock); @@ -1674,6 +1758,13 @@ static void vfio_iommu_type1_detach_group(void *iommu_data, } } + /* + * Get a copy of iova list. If success, use copy to update the + * list and to replace the current one. + */ + INIT_LIST_HEAD(&iova_copy); + iova_copy_fail = !!vfio_iommu_get_iova_copy(iommu, &iova_copy); + list_for_each_entry(domain, &iommu->domain_list, next) { group = find_iommu_group(domain, iommu_group); if (!group) @@ -1699,10 +1790,22 @@ static void vfio_iommu_type1_detach_group(void *iommu_data, iommu_domain_free(domain->domain); list_del(&domain->next); kfree(domain); + if (!iova_copy_fail) + vfio_iommu_aper_expand(iommu, &iova_copy); } break; } + if (!iova_copy_fail) { + if (!vfio_iommu_resv_refresh(iommu, &iova_copy)) { + /* Delete the current one and insert new iova list */ + vfio_iommu_insert_iova_copy(iommu, &iova_copy); + goto detach_group_done; + } + } + + list_for_each_entry_safe(iova, iova_next, &iova_copy, list) + kfree(iova); detach_group_done: mutex_unlock(&iommu->lock); } -- 2.7.4
