On Thu, 15 Feb 2018 09:45:00 +0000
Shameer Kolothum <shameerali.kolothum.thodi@xxxxxxxxxx> wrote:
> This retrieves the reserved regions associated with dev group and
> checks for conflicts with any existing dma mappings. Also update
> the iova list excluding the reserved regions.
>
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@xxxxxxxxxx>
> ---
> drivers/vfio/vfio_iommu_type1.c | 86 ++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 85 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 4726f55..4db87a9 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -1303,6 +1303,72 @@ static int vfio_iommu_aper_resize(struct list_head *iova,
> return 0;
> }
>
> +/*
> + * Check reserved region conflicts with existing dma mappings
> + */
> +static bool vfio_iommu_resv_conflict(struct vfio_iommu *iommu,
> + struct list_head *resv_regions)
> +{
> + struct iommu_resv_region *region;
> +
> + /* Check for conflict with existing dma mappings */
> + list_for_each_entry(region, resv_regions, list) {
> + if (vfio_find_dma(iommu, region->start, region->length))
> + return true;
> + }
> +
> + return false;
> +}
> +
> +/*
> + * Check iova region overlap with reserved regions and
> + * exclude them from the iommu iova range
> + */
> +static int vfio_iommu_resv_exclude(struct list_head *iova,
> + struct list_head *resv_regions)
> +{
> + struct iommu_resv_region *resv;
> + struct vfio_iova *n, *next;
> +
> + list_for_each_entry(resv, resv_regions, list) {
> + phys_addr_t start, end;
> +
> + start = resv->start;
> + end = resv->start + resv->length - 1;
> +
> + list_for_each_entry_safe(n, next, iova, list) {
> + int ret = 0;
> +
> + /* No overlap */
> + if ((start > n->end) || (end < n->start))
> + continue;
> + /*
> + * Insert a new node if current node overlaps with the
> + * reserve region to exlude that from valid iova range.
> + * Note that, new node is inserted before the current
> + * node and finally the current node is deleted keeping
> + * the list updated and sorted.
> + */
> + if (start > n->start)
> + ret = vfio_insert_iova(n->start, start - 1,
> + &n->list);
> + if (!ret && end < n->end)
> + ret = vfio_insert_iova(end + 1, n->end,
> + &n->list);
> + if (ret)
> + return ret;
> +
> + list_del(&n->list);
> + kfree(n);
> + }
> + }
> +
> + if (list_empty(iova))
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> static int vfio_iommu_get_iova_copy(struct vfio_iommu *iommu,
> struct list_head *iova_copy)
> {
> @@ -1346,7 +1412,8 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> bool resv_msi, msi_remap;
> phys_addr_t resv_msi_base;
> struct iommu_domain_geometry geo;
> - struct list_head iova_copy;
> + struct list_head iova_copy, group_resv_regions;
> + struct iommu_resv_region *resv, *resv_next;
> struct vfio_iova *iova, *iova_next;
>
> mutex_lock(&iommu->lock);
> @@ -1426,6 +1493,14 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> goto out_detach;
> }
>
> + INIT_LIST_HEAD(&group_resv_regions);
LIST_HEAD()
> + iommu_get_group_resv_regions(iommu_group, &group_resv_regions);
> +
> + if (vfio_iommu_resv_conflict(iommu, &group_resv_regions)) {
> + ret = -EINVAL;
> + goto out_detach;
> + }
> +
> /* Get a copy of the current iova list and work on it */
> INIT_LIST_HEAD(&iova_copy);
> ret = vfio_iommu_get_iova_copy(iommu, &iova_copy);
> @@ -1437,6 +1512,10 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> if (ret)
> goto out_detach;
>
> + ret = vfio_iommu_resv_exclude(&iova_copy, &group_resv_regions);
> + if (ret)
> + goto out_detach;
> +
> resv_msi = vfio_iommu_has_sw_msi(iommu_group, &resv_msi_base);
>
> INIT_LIST_HEAD(&domain->group_list);
> @@ -1497,6 +1576,9 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> /* Delete the old one and insert new iova list */
> vfio_iommu_insert_iova_copy(iommu, &iova_copy);
>
> + list_for_each_entry_safe(resv, resv_next, &group_resv_regions, list)
> + kfree(resv);
list_del() here and below, also this can be done after the mutex unlock.
> +
> mutex_unlock(&iommu->lock);
>
> return 0;
> @@ -1507,6 +1589,8 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
> iommu_domain_free(domain->domain);
> list_for_each_entry_safe(iova, iova_next, &iova_copy, list)
> kfree(iova);
> + list_for_each_entry_safe(resv, resv_next, &group_resv_regions, list)
> + kfree(resv);
> out_free:
> kfree(domain);
> kfree(group);
